CHAPTER IV.

THE PRINCIPLES AND PRACTICE OF COTTON DYEING.

Students of cotton dyeing should have a good knowledge of the principles

that underlie the processes of dyeing cotton fabrics. It is only by

recognising these principles and then endeavouring to apply them to each

individual case of dyeing, that the dyer or student will obtain a

thorough grasp of his subject. It is the aim of the author to lay down

these principles in a clear and intelligible form. Cotton is dyed in its

loose raw condition, as yarn in the form of hanks, yarn in the form of

cops, and in the woven pieces of every kind. Formerly the idea was

prevalent among cotton dyers that the process which succeeds with piece

goods would not answer with yarns. It is now recognised however that

this is not so, that a process which will dye cotton yarn will also dye

cotton piece goods or loose cotton. The differences which do exist in

the practical working of the processes entirely arise from the

difference in the form in which the cotton is presented to the dyer, for

it must be obvious to any one that the mode of handling a piece of

cotton cloth during the time it is in the dye-bath must be different

from that of a hank of yarn, a parcel of loose cotton or a number of

cops. The various machines used for dyeing all these forms and the

manner of working them have been already described.

The dyes, whether natural--derived from the various dye-woods, etc.--or

artificial--prepared from coal tar--may according to their varied

chemical composition and constitution be divided into seventeen or

eighteen distinct groups, but it is not intended here to give any

account of them; the reader is referred to other books such as _The

Dictionary of Coal Tar Colours_, by George H. Hurst; _The Chemistry of

Coal Tar Colours_, by Benedikt and Knecht; or _The Chemistry of Organic

Colouring Matters_, by Nietzki, where the composition and properties of

the dyes are fully described.

From the manner in which the various dyes are applied to cotton, linen,

wool and other fibres we can divide them into five groups, thus:--

Group 1. Direct dyes.

" 2. Basic dyes.

" 3. Acid dyes.

" 4. Mordant dyes.

" 5. Miscellaneous dyes.

First group, direct dyes, are now very numerous; they dye cotton, linen

and other vegetable fibres from a plain bath, and do not require those

fibres to be prepared in any way. Hence the reason of their being named

direct, or by some the substantive colours. They will also dye wool and

silk.

The second group, basic dyes, comprise some of the oldest of the

coal-tar dyes; they dye wool and silk direct from plain baths, but

require cotton, linen and other vegetable fibres to be previously

prepared in baths of tannic acid, sumach or other tanning material.

The third group, acid dyes, are very numerous, and from both their

chemical composition and mode of dyeing can be divided into several

sub-groups. Their principal feature is that they dye wool and silk from

baths containing Glauber's salt and some acid, hence their name of "acid

dyes". They do not dye cotton or linen well, some not at all, others are

absorbed to a slight extent by the cotton, but only pale tints are

produced, while others may be used along with metallic mordants to dye

bright but pale and fugitive shades. The acid dyes comprise such as Acid

green, Formyl violet, Acid magenta, Azo scarlet, Orange. Thiocarmine R.,

Patent blues, Wool greens, indigo extract, Eosines, etc.

The fourth group, mordant dyes, includes the alizarine series of

coal-tar colours, logwood, Brazil wood and most natural colours, and

some others. The principal feature of these dyes is that they require

the cotton to be prepared with some metallic oxide, like those of

chrome, alumina and iron, before dyeing, and the colour which is got

depends partly upon the particular dye-stuff used and partly upon the

oxide with which the cotton has been prepared.

The fifth group includes a few dyes like indigo, which are dyed on to

cotton by various and special processes.

The processes of cotton dyeing employed to-day may be comprised under

eight heads, namely:--

(1) Direct dyeing.

(2) Direct dyeing followed by fixation with metallic salts.

(3) Direct dyeing followed by fixation with developers.

(4) Direct dyeing followed by fixation with couplers.

(5) Dyeing on tannic mordant.

(6) Dyeing on metallic mordant.

(7) Developing the colour direct on fibre.

(8) Dyeing by impregnating the cotton with the dye-stuff,

followed by oxidation or steaming.

It is of course not easy to elaborate a simple scheme of grouping the

processes that shall definitely include all processes, but the above

grouping will be found as successful as any, and each will be considered

as fully as is deemed necessary.

(1) DIRECT DYEING.

Nothing in the history of cotton dyeing caused such a revolution in the

methods of working as did the introduction some fifteen years ago of the

forerunners (Congo red, Benzo purpurine, Chrysamine, Azo blue) of the

now numerous group of direct dyes, followed as they were by the Benzo,

Congo, Diamine, Titan, Chicago and Zambesi members of the group. Prior

to their introduction cotton dyeing was always more or less complicated

and mordanting methods had to be employed.

With the introduction of the direct dyes cotton dyeing has become even

more simple than wool or silk dyeing, and now all that is necessary is

to prepare a dye liquor containing the necessary amount of dye-stuff and

Glauber's salt, or common salt or soda, or some similar body, or a

combination thereof. The method of working is to place the cotton in a

lukewarm or even in a hot bath, raise to the boil, allow the goods to

remain in the boiling bath for half an hour to an hour, then take them

out, wring, wash and dry. This method is simple and will answer for all

the dyes of this group. There are some that do not require the working

to be done boiling; it is simply needful to enter the cotton into a

boiling bath and work without steam until the bath has cooled down.

Furious boiling is not needed--a gentle simmer gives the best results.

Uneven dyeing seems to be an impossibility in this group of dyes, unless

the cotton is dirty; no matter how the operations are carried on, level

dyeing is the rule not the exception. An enormous variety of shades and

tints can be obtained from these dyes, and they can be combined together

in every conceivable manner and proportions.

No satisfactory explanation has yet been given as to what feature in the

chemical composition of these dye-stuffs give them such an affinity for

the cotton fibre as to enable them to dye in so simple a manner such

fast shades as they do; it is a fact there is such an affinity and there

the matter must rest.

It has been found in practice that the efficiency of the dyeing

operation depends, primarily of course, on the particular dye-stuff

used, but also upon other factors, that a certain assistant be used.

Some dyes work on the cotton better from a bath containing Glauber's

salt, while with others common salt works best, while a little soda

along with the salt facilitates the dyeing in some cases. It is

practically impossible to specify here the best assistant for all the

direct colours, on account of the great number of such dyes which are

known, but in the practical recipes given below much useful advice will

be found. Then the quantity of such assistants used is of much

importance; there is one proportion at which the best results are

obtained for each dye. The dyer should find out for himself by

experiment and the use of the dyes he employs in his work what assistant

and how much is best, and make his baths up to that strength. With some

dyes 10 per cent. of the assistant will be found sufficient, while with

others, 25 to 30 per cent. will not be too much. The percentage refers

to the weight of the cotton that is taken.

One function of the assistants must be pointed out here: it is that in

some cases they--especially the alkaline ones, soda, potash, borax,

phosphate of soda--help the dyeing by promoting the solubility of the

dye-stuff in the bath, thereby retarding the exhaustion of the bath and

ensuring the production of level shades.

The following formulas show the application of the foregoing principles

to the dyeing of numerous shades on to cotton and also the dyes which

are applicable, some of the combinations which are possible with these

direct dyes, and give some idea of the tints and shades of the colours

that can be got by their means. The best assistants to use are also

indicated in the formulæ.

All the formulæ here given and all that will be given in future chapters

are intended for 100 lb. weight of cotton fabrics in any condition,

whether of loose cotton, yarn in cops, hanks or wraps and woven fabrics

of every kind.

_Bright Red._--Dye with 3 lb. Benzo purpurine 4 B, 3 lb. soda and 15 lb.

Glauber's salt. This dye may also be used with 3 lb. soap and 10 lb.

soda in the bath with equally good results.

_Pale Salmon._--Prepare a dye-bath with 3 lb. salt, 5 lb. phosphate of

soda, 1 lb. soap, 1/2 oz. Benzo orange R. For a pale shade like this it

is not necessary to heat to the boil, a temperature of 170° to 180° F.

is sufficient.

_Dark Plum._--Prepare a dye-bath with 20 lb. of Glauber's salt, 2-1/2

lb. soap, 1-1/2 lb. Diamine black R O. and 2 lb. Diamine red N. Enter at

180° F., work for a few minutes, then raise to boil and dye to shade;

lift, wash and dry.

_Turkey Red._--Prepare a dye-bath with 1-1/2 lb. Benzo purpurine 4 B, 1

lb. Brilliant purpurine, 2 lb. soap, 10 lb. borax. Enter the cotton at

the boil and work for one hour; lift, wash and dry.

_Lilac Red._--Prepare the dye-bath with 2 lb. soap, 5 lb. soda, 3 lb.

Rose azurine G. Work at the boil for one hour.

_Pink._--Prepare a bath containing 10 lb. soda, 1 oz. Rose azurine B.

Enter at a boil and work for one hour, boiling to shade; lift, wash and

dry.

_Bordeaux._--Prepare a dye-bath with 15 lb. Glauber's salt, 5 lb. soda

crystals, 3 lb. Diamine fast red F, 1 lb. Diamine violet N, 1 lb. Rose

azurine G. Enter cold, then raise to the boil, and work for one and a

half hours; lift, wash and dry.

_Rose Pink._--The dye-bath is made with 2 lb. Erika B, 20 lb. Glauber's

salt and 3 lb. soap, working at near the boil to shade.

_Brilliant Red._--Make the dye-bath with 24 lb. Brilliant purpurine R

and 25 lb. Glauber's salt, working at the boil for one hour.

_Deep Pink._--Make the dye-bath with 1/2 lb. Diamine rose B D, 1/2 lb.

soda, 1 lb. soap and 5 lb. Glauber's salt, working at 150° F. for half

an hour.

_Dark Red._--Use in the dye-bath 3 lb. Diamine red 5 B, 2 lb. soda and

20 lb. Glauber's salt, working at the boil for one hour.

_Pink._--Prepare the dye-bath with 4 oz. Diamine rose B D, 1 lb.

Turkey-red oil, 40 lb. Glauber's salt. Dye at the boil for one hour.

_Scarlet._--Prepare the dye-bath with 4 lb. Diamine scarlet 3 B, 1 lb.

Turkey-red oil, 20 lb. Glauber's salt. Dye at the boil for one hour.

_Scarlet._--Prepare the dye-bath with 3 lb. Titan scarlet C, 1/2 lb.

Titan orange, 50 lb. salt. Work at the boil for thirty minutes, then

lift, wash and dry. The dye-bath is not exhausted and may be used for

further lots.

_Crimson Red._--Prepare the dye-bath with 5 lb. Titan scarlet D and 50

lb. salt. Work at the boil for fifty minutes, then lift, wash and dry.

The bath is not exhausted, the cotton taking up only about 3 lb. of the

dye-stuff; it may therefore be kept for further use, when for each

succeeding lot 3 to 3-1/2 lb. of colour and 25 lb. of salt only need be

added.

_Scarlet._--Prepare the dye-bath with 5 lb. Rosophenine 5 B, dissolved

in 50 gallons hot water, 2 gallons caustic soda lye (60° Tw.). When

thoroughly dissolved add 150 lb. salt. Make up the bath to 100 gallons.

Enter the yarn and work for a quarter to half an hour at about 180° F;

squeeze off and wash thoroughly in cold water until the water runs off

clean.

_Rose Red._--Use 1 lb. Diamine red 10 B, 3 lb. soda, and 20 lb.

Glauber's salt.

_Deep Crimson._--Use 3 lb. Diamine red 10 B, 3 lb. soda and 20 lb.

Glauber's salt.

_Claret._--Use 3 lb. Diamine Bordeaux B, 3 lb. soda and 20 lb. Glauber's

salt.

_Pink._--The dye-bath is made with 5 oz. Dianil red 4 B, 5 lb. salt and

3 lb. soda.

_Scarlet._--Use in the dye-bath 3 lb. Dianil red 4 B, 15 lb. salt and 5

lb. soda. Work at the boil for one hour.

_Claret._--Dye with 1-1/2 lb. Dianil claret G, 3 lb. soda and 20 lb.

salt. Work at the boil for one hour.

_Maroon._--Dye with 3 lb. Dianil claret B, 3 lb. soda and 20 lb. salt.

Work at the boil for one hour.

_Bright Scarlet._--Use in the dye-bath 2-1/2 lb. Dianil red 4 B 5 oz.

Dianil orange G, 3 lb. soda and 15 lb. salt.

_Dark Maroon._--Make the dye-bath with 1 lb. Dianil red 4 B, 2 lb.

Dianil claret G, 13 oz. Dianil claret B, 5 lb. soda and 20 lb. salt.

_Crimson._--Dye with 3 lb. Congo rubine, 5 lb. soda and 20 lb. Glauber's

salt.

_Dark Maroon._--Use in the dye-bath 1 lb. Benzo purpurine 4 B, 3 lb.

Congo Corinth G, 3 lb. soda and 20 lb. Glauber's salt, working at the

boil to shade.

_Pale Fawn Red._--Use in the dye-bath 1-1/2 oz. Diamine red 5 B, 1-1/2

oz. Diamine catechine G, 3 lb. soda and 10 lb. Glauber's salt.

_Rose Red._--Prepare the dye-bath with 3/4 lb. Diamine Bordeaux B, 3 oz.

Diamine orange B, 3 lb. soda and 20 lb. salt.

_Crimson._--Use in the dye-bath 3/4 lb. Diamine Bordeaux B, 3 oz.

Diamine fast yellow B, 3 lb. soda and 20 lb. Glauber's salt.

_Salmon._--Dye with 1-1/2 oz. Diamine fast red F, 1-1/2 oz. Diamine fast

yellow B, 3 lb. soda and 10 lb. Glauber's salt.

_Terra-Gotta Red._--Dye with 1-1/2 lb. Diamine brown M, 3/4 lb. Diamine

fast red F, 3 lb. soda and 20 lb. Glauber's salt.

_Lilac Red._--Dye with 4 lb. Heliotrope B B, 3 lb. soda and 15 lb.

Glauber's salt.

_Bright Pink._--Use in the dye-bath 2 oz. Rose azurine G, 1 lb. soda and

10 lb. Glauber's salt. Nearly all the direct reds give good pink tints

when used in proportion, varying from 0.1 to 0.25 per cent. of

dye-stuff.

_Bright Straw._--Dye in a bath made of 1/4 lb. Titan yellow G G, 10 lb.

salt, for three-quarters of an hour, then lift, wash and dry.

_Yellow._--Prepare a dye-bath with 1 lb. Titan yellow Y, 10 lb. salt.

Heat to 180° F., enter the goods, raise to boil, and dye for one hour;

lift, wash and dry.

_Yellow._--Prepare the dye-bath with 1/4 lb. Diamine fast yellow A, 1

lb. Turkey red oil, 20 lb. Glauber's salt. Dye at the boil for one hour.

_Sun Yellow._--Prepare the dye-bath with 2 lb. Sun yellow, 30 lb. common

salt. Dye at the boil. The bath is kept for further lots.

_Yellow._--Prepare the dye-bath with 1 lb. Direct yellow R, 20 lb.

Glauber's salt. Dye at the boil for one hour.

_Yellow._--Prepare the dye-bath with 2 lb. Curcuphenine, 20 lb. common

salt. Work at the boil for one hour; lift, rinse and dry.

_Old Gold._--Make the dye-bath with 5 lb. Diamine yellow N powder, 20

lb. phosphate of soda, 10 lb. soap. Work at the boil for one hour;

finish in the usual way. The bath may be kept for other lots of goods.

_Dark Yellow._--The bath is made from 2 lb. Toluylene orange G, 10 lb.

phosphate of soda, and 2-1/2 lb. soap, working at the boil to shade.

_Bright Yellow._--Use 1 lb. Chrysophenine, 2 lb. phosphate of soda and

10 lb. Glauber's salt.

_Lemon Yellow._--Use 1 oz. Chrysamine G, 2 lb. phosphate of soda and 10

lb. Glauber's salt.

_Yellow._--Dye with 2 lb. Oxyphenine and 20 lb. salt.

_Yellow Olive._--Use in the dye-bath 2 oz. Cotton brown N, 4-1/2 oz.

Diamine bronze G, 4-1/2 oz. Diamine fast yellow B, 3 lb. soda and 20 lb.

salt.

_Green Yellow._--Dye with 1/2 lb. Diamine fast yellow B. 2 oz. Diamine

bronze G, 3 lb. soda and 10 lb. Glauber's salt.

_Gold Yellow._--Use in the dye-bath 3 lb. Columbia yellow, 3 lb. soda

and 20 lb. Glauber's salt.

_Cream._--Dye with 1/2 oz. Toluylene orange G, 24 grains Brilliant

orange G, 1 lb. soda and 10 lb. Glauber's salt.

_Primrose._--Dye with 3 oz. Dianil yellow 3 G, 2 lb. soda and 10 lb.

salt.

_Gold Yellow._--Dye with 2-1/2 lb. Dianil yellow G, 1/2 lb. soda and 15

lb. salt.

_Buff Yellow._--Dye with 3-1/2 oz. Dianil yellow 2 R, 1/2 lb. soda and

10 lb. salt.

_Orange._--Prepare the dye-bath with 2 lb. Chlorophenine orange R, 20

lb. common salt. Work at the boil for one hour; lift, rinse and dry.

_Red Orange._--Make the dye-bath with 3 lb. Mikado orange 4 R and 25 lb.

salt. Work at the boil for one hour.

_Orange._--Make the dye-bath with 3 lb. Mikado orange G and 25 lb. salt.

Work at the boil for one hour.

_Pale Orange._--The dye-bath contains 6 oz. Diamine Orange G, 1-1/2 oz.

Diamine fast yellow B, 1/4 oz. Diamine scarlet B, 3 lb. soda and 15 lb.

Glauber's salt.

_Olive Yellow._--Dye with 3/4 lb. Diamine fast yellow B, 1 oz.

Oxydiamine black N, 1-1/2 oz. Diamine bronze G, 3 lb. soda and 20 lb.

Glauber's salt.

_Dark Orange._--Dye with 3 lb. Columbia orange R, 3 lb. soda and 20 lb.

Glauber's salt at the boil for one hour.

_Bright Orange._--Use 3 lb. Congo orange R, 3 lb. soda and 20 lb.

Glauber's salt at the boil for one hour.

_Pale Orange._--Dye with 3 lb. Dianil orange 2 R, 2 lb. soda and 10 lb.

salt at the boil for one hour.

_Brilliant Orange._--Dye with 4 lb. Dianil orange G and 20 lb. salt for

one hour.

_Deep Orange._--Dye with 2 lb. Oxydiamine orange R, 3/4 lb. soda and 20

lb. salt for an hour.

_Pale Orange._--Dye with 3/4 lb. Diamine fast yellow B, 1 lb. Diamine

orange B, 3 lb. soda and 15 lb. Glauber's salt.

_Bright Orange._--Dye with 1-1/2 lb. Benzo orange R, 1-1/2 lb.

Chrysamine R, 10 lb. phosphate of soda and 2 lb. soap.

_Green._--Prepare the dye-bath with 2 lb. Benzo green G, 10 lb.

Glauber's salt. Enter lukewarm, bring slowly to the boil, dye for one

hour at the boil.

_Russian Green._--Make the dye-bath with 16 oz. Diamine black H W, 4 oz.

Diamine fast yellow A, 3 lb. soda, 15 lb. Glauber's salt, working at the

boil for one hour, then lift, wash and dry.

_Dark Olive._--Prepare a dye-bath with 3-1/2 lb. Benzo olive, 2-1/2 lb.

Diamine black B O, 2 lb. Diamine yellow, 20 lb. common salt, 2 lb. soap.

The goods are entered into the bath at 160° F., then heat is raised to

the boil, and the dyeing continued for one hour, then lift, wash and

dry.

_Dark Olive._--Dye in a bath of 2 lb. Titan yellow Y, 1 lb. Diamine

brown Y, 1-1/2 lb. Diamine blue 3 B, 2 lb. soda. Work for one hour, then

lift, wash and dry.

_Olive._--Prepare a dye-bath with 15 lb. phosphate of soda, 3 lb. soap,

1-1/2 lb. Diamine yellow N, 4 oz. Diamine blue 3 B, 1-1/2 oz. Diamine

brown V. Dye at the boil to shade; lift, wash and dry.

_Green Olive._--Prepare the dye-bath with 1 lb. Diamine black R O, 1 lb.

Chrysamine, 1/4 lb. Benzo brown, 5 lb. soda, 5 lb. salt, 2 lb. soap. The

goods are entered at about 180° F. and worked for a short time, then

the temperature is raised to the boil, and the goods are worked for one

hour, lifted, washed and dried.

_Reseda._--Prepare a bath with 10 lb. Glauber's salt, 2 lb. soap, 1/2

lb. Diamine black R O, 2 lb. Diamine yellow N. Enter at 120° F., heat to

boil and dye for one hour at that temperature; lift, wash and dry.

_Sage Green._--Prepare a dye-bath with 10 lb. Glauber's salt, 1/2 lb.

Diamine black R O, 2 lb. Diamine yellow N. Enter at about 150° F. and

then raise to boil and dye boiling for one hour, wash and dry.

_Drab._--Prepare the dye-bath with 10 lb. Cross dye drab, 5 lb. soda

crystals. Enter at the boil and work at this temperature for half an

hour. Whilst dyeing add gradually 75 lb. salt. Rinse well and dry.

_Olive._--Prepare the dye-bath with 2 lb. Dianil olive, 5 lb. phosphate

of soda, 5 lb. common salt. Dye at the boil for one hour.

_Olive._--The dyeing is done in a bath containing 4 oz. Diamine black H

W, 1-3/4 lb. Diamine bronze G, 5 lb. soda, 15 lb. Glauber's salt. Work

at the boil for one hour.

_Grass Green._--Make the dye-bath with 2 lb. Chrysamine G, 1-1/2 oz.

Benzo azurine G, 3 lb. soap and 10 lb. borax, working at the boil for

one hour.

_Green._--Make the dye-bath with 2 lb. Titan yellow Y, 1 lb. Titan blue

3 B and 20 lb. salt.

_Bright Grass Green._--Dye for an hour at the boil with 1 lb. Sulphon

azurine D, 2 lb. Thiazole yellow and 20 lb. Glauber's salt.

_Green._--Use in the dye-bath 3 lb. Diamine green B, 3 lb. soda and 20

lb. Glauber's salt, working at the boil to shade.

_Dark Green._--Dye with 3 lb. Diamine dark green N, 3 lb. soda and 20

lb. Glauber's salt.

_Green._--Use in the bath 3 lb. Benzo green B B, 3 lb. soda and 20 lb.

Glauber's salt at the boil for one hour.

_Dark Sea Green._--Dye with 5 oz. Diamine black H W, 3 oz. Diamine

catechine G, 3 oz. Diamine fast yellow B, 3 lb. soda and 10 lb.

Glauber's salt.

_Pale Green._--Use in the dye-bath 3 lb. Diamine fast yellow B, 2 oz.

Diamine black H W, 3 lb. soda and 10 lb. Glauber's salt.

_Bright Pea Green._--Use in the dye-bath 1 oz. Thioflavine S, 1/4 oz.

Diamine sky blue F F and 20 lb. Glauber's salt.

_Dark Green._--Use 1-3/4 lb. Diamine green G, 3/4 lb. Oxydiamine yellow

G G, 3 lb. soda and 20 lb. Glauber's salt, working at the boil for one

hour.

_Deep Green._--Use 1-3/4 lb. Diamine green G, 3/4 lb. Diamine black B H,

1/2 lb. Oxydiamine yellow G G, 3 lb. soda, and 20 lb. Glauber's salt.

_Sea Green._--Use 2 oz. Dianil yellow R, 2-1/2 oz. Dianil blue B, 1-3/4

oz. Dianil dark blue R, 1 lb. soda, and 20 lb. salt, working at the

boil.

_Leaf Green._--Dye with 1-1/2 lb. Dianil yellow 3 G, 1 lb. Dianil blue

B, 11 oz. Dianil blue 2 R, 3 lb. soda, and 20 lb. salt at the boil for

one hour.

_Deep Green._--Dye with 2-1/2 lb. Dianil yellow 3 G, 2-1/2 lb. Dianil

blue 2 R, 6 oz. Dianil dark blue R, 3 lb. soda, and 20 lb. salt at the

boil for one hour.

Greens are largely produced by mixing yellows and blues together as will

be seen from the recipes given above; the particular shade of green

which is got from a combination of blue and green depends upon the

quality of the dye-stuffs used: thus, to produce bright greens of a pure

tone, it is essential that the yellow used shall have a greenish tone

like Thioflavine S, Thiazole yellow, or Dianil yellow 3 G, while the

blue must also have a greenish tone like Diamine sky blue, Benzo blue 3

B, etc. By using yellows like Diamine fast yellow R, and dark blues like

Benzo azurine 3 R, Diamine blue R W, Dianil dark blue R, the green which

is got is darker and duller in tone. The addition of such a dye as

Diamine black B H throws the shade more on to an olive, while a brown

dye-stuff, like Diamine brown M, or an orange dye, like Titan orange N,

throws the green on to a sage tone. Examples of these effects will be

found among the recipes given above.

It may be added here that by using smaller quantities, but in the same

proportions as given in the above recipes, a great range of tints and

shades of green can be dyed from very pale to very deep.

_Bright Blue._--Prepare a dye-bath with 1/2 lb. Congo blue 2 B, 5 lb.

salt, 5 lb. phosphate of soda, 2 lb. soap. Work at the boil for one

hour, then rinse and dry.

_Dark Navy._--Prepare a dye-bath with 1 lb. Diamine black R O, 2 lb.

Diamine blue 3 R, 8 lb. Glauber's salt, 2 lb. soap. Enter the cotton at

180° F., and boil for one hour.

_Pale Blue._--Prepare a dye-bath with 10 lb. salt, 3 lb. soda, 3 oz.

diamine blue 3 R. Work for one hour at the boil, then lift, wash and

dry.

_Sky Blue._--Prepare a dye-bath with 2 lb. Titan como G, 20 lb. common

salt, 2 oz. acetic acid. Work at the boil for half an hour, then lift,

wash and dry.

_Bright Blue._--Prepare the dye-bath with 1-1/2 lb. Chicago blue 6 B, 20

lb. Glauber's salt, 3 lb. soap. Work at the boil for one hour, then

lift, wash and dry.

_Pale Sky Blue._--Make the dye-bath with 1 oz. Chicago blue 6 B, 10 lb.

Glauber's salt, 2 lb. soap. Work at the boil for one hour, then lift,

wash and dry.

_Sky Blue._--Prepare the dye-bath with 1 lb. Diamine sky blue F F, 1 lb.

Turkey-red oil, 20 lb. Glauber's salt. Dye at the boil for one hour.

_Dark Blue._--Prepare the dye-bath with 2-1/2 lb. Diamineral blue R,

2-1/2 lb. Diamine deep black Cr, 1 lb. Turkey-red oil, 40 lb. Glauber's

salt. Dye at the boil for one hour.

_Dark Blue._--Prepare the dye-bath with 3 lb. Triamine black B, 15 lb.

Glauber's salt, in 50 gallons of water. Enter at 150° F., and boil for

one hour. Allow the goods to remain until the water is cold, when the

dye-bath will be completely exhausted.

_Blue._--Prepare the dye-bath with 2 lb. Diamine steel blue L, 2 lb.

soda, 15 lb. Glauber's salt. Dye at the boil for one hour.

_Blue._--Prepare the dye-bath with 4 lb. Diamine blue B G, 2 lb. soda,

20 lb. Glauber's salt. Dye at the boil for one hour. In shade this is

very similar to that got with Diamine brilliant blue G, which however

should be used for light shades on account of its brightness. For deep

shades Diamine blue B G, is preferable, because of its greater

tinctorial power.

_Light Indigo Blue._--Prepare the dye-bath with 1 lb. Paramine indigo

blue, 2 lb. soda, 20 lb. Glauber's salt. Enter at about 150° F., and dye

at the boil for one hour.

_Navy Blue._--Prepare the dye-bath with 4 lb. Paramine navy blue R, 2

lb. soda, 20 lb. Glauber's salt. Enter at about 150° F., and dye at the

boil for one hour.

_Blue._--Prepare the dye-bath with 1 lb. Paramine navy blue R, 2 lb.

soda, 20 lb. Glauber's salt. Enter at about 150° F., and dye at the boil

for one hour.

_Navy Blue._--Prepare the dye-bath with 4 lb. Benzo chrome black blue B,

15 lb. Glauber's salt, 3 lb. soda. Work at the boil for one hour; lift,

rinse and dry.

_Grey Blue._--Prepare the dye-bath with 2 lb. Paramine blue black S, 2

lb. soda, 20 lb. Glauber's salt. Enter at 150° F., and dye for one hour

at boil.

_Blue._--Prepare the dye-bath with 1 lb. Paramine blue B, 2 lb. soda, 20

lb. Glauber's salt. Enter at about 150° F., and dye at the boil for one

hour.

_Slate Blue._--Prepare the dye-bath with 1/4 lb. Diamine black B H, 3/4

oz. Diamine fast yellow B, 2 lb. soda, and 10 lb. Glauber's salt. Dye at

the boil to shade.

_Deep Blue._--Use 3-1/4 lb. Diamine blue B X, 1/2 lb. Oxydiamine black

N, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

_Blue._--Dye at the boil for one hour with 1-1/2 lb. Diamine sky blue, 2

oz. Diamine green B, 2 lb. soda and 10 lb. Glauber's salt.

_Navy._--Dye with 1 lb. Dianil dark blue R, 8 oz. Dianil black C R, 5

lb. soda and 20 lb. salt at the boil for one hour.

_Dark Navy._--Use 2 lb. Dianil blue B, 2 lb. Dianil dark blue R, 3/4 lb.

Dianil black C R, 2 lb. soda and 25 lb. salt, working at the boil for

one hour.

_Deep Blue._--Dye with 3-1/2 lb. Diamine blue black E, 5 lb. soda and 20

lb. Glauber's salt at the boil for one hour.

_Deep Blue._--Dye with 3 lb. Zambesi black B R, 3 lb. soda and 20 lb.

Glauber's salt at the boil for one hour.

_Dark Navy._--Use 3 lb. Dianil dark blue R, 3 lb. caustic soda 70° Tw.,

and 25 lb. salt, working at the boil for one hour.

_Violet Blue._--Dye with 3 lb. Dianil dark blue 3 R and 25 lb. salt at

the boil for one hour.

_Bright Blue._--Use 1 lb. Dianil blue B, and 20 lb. salt, working at the

boil for one hour.

_Full Blue._--Dye with 3 lb. Brilliant azurine 5 G, 5 lb. common salt, 5

lb. phosphate of soda and 2 lb. soap at the boil for one hour.

_Dark Blue._--Dye with 3 lb. Erie blue B X, 3 lb. soda and 20 lb.

Glauber's salt at the boil for one hour.

_Pale Blue._--Dye with 1 lb. Chicago blue 6 B, 3 lb. soda and 20 lb.

salt at the boil for one hour.

_Deep Blue._--Dye with 1-1/2 lb. Oxydiamine black A, 2 lb. Diamine deep

blue R, 3 lb. soda and 20 lb. Glauber's salt at the boil for one hour.

_Blue._--Dye with 6 oz. Diamine blue 3 B, 1-1/2 oz. Diamine sky blue F

F, 3 lb. soda and 10 lb. Glauber's salt.

_Navy._--Dye with 4 lb. Diamine new blue R, 3 lb. soda and 20 lb.

Glauber's salt at the boil for one hour.

_Dark Navy._--Dye with 1-3/4 lb. Diamineral blue R, 3 lb. soda and 20

lb. Glauber's salt at the boil for one hour.

_Sky Blue._--Prepare the dye-bath with 6 oz. Diamine sky blue F F, 3 lb.

soda and 10 lb. Glauber's salt, working at the boil for one hour.

_Dark Blue._--Use in the dye-bath 3 lb. Diamine blue R W, 2 lb. soda and

20 lb. Glauber's salt, working at the boil for one hour.

_Dark Blue._--Prepare the dye-bath with 3 lb. Triamine black B T, and 15

lb. Glauber's salt; work at the boil to shade.

_Blue._--Use 2 lb. Direct indigo blue and 15 lb. Glauber's salt; work at

the boil.

_Bright Blue._--Use in the dye-bath 3 lb. Titan como S N, 2 lb. acetic

acid and 20 lb. salt, working at the boil for one hour.

_Turquoise Blue._--Dye with 1 lb. Diamine sky blue, 1 oz. Diamine fast

yellow B, 2 lb. soda and 10 lb. Glauber's salt, working at the boil to

shade.

_Dark Navy._--Use 4 lb. Titan navy R, and 20 lb. salt at the boil for

one hour.

_Green Blue._--Dye with 1 lb. Dianil blue G, 2-1/2 oz. Dianil yellow G,

1 lb. soda and 20 lb. salt at the boil for one hour.

Many more formulæ could have been given, but the above will perhaps

suffice; they include all the best of the direct blues. Paler tints of

blue may be got by using from 1 to 2 per cent. of any of these blues and

also of the many direct blacks now on the market. The direct blues as a

rule have a good degree of fastness to light.

_Lilac._--Prepare a dye-bath with 1/4 lb. Hessian brown 2 M, 1 oz. Azo

mauve A M, 1 lb. soap, 2 lb. soda, 10 lb. salt. Work at the boil for one

hour, then lift, wash and dry.

_Plum._--Dye with 3 lb. Oxydiamine violet G, 3 lb. soda and 20 lb. salt.

_Dark Plum._--Use in the dye-bath 3 lb. Oxydiamine violet B, 3 lb. soda

and 20 lb. Glauber's salt, working at the boil.

_Violet._--Make the dye-bath with 3/4 lb. Oxydiamine violet B, 1 lb.

soda and 10 lb. Glauber's salt, and dye at the boil to shade.

_Violet._--Dye with 12 oz. Dianil blue 4 R, 2 oz. Dianil blue B and 10

lb. salt at the boil.

_Lilac._--Dye with 1-1/2 oz. Diamine rose G D, 3/4 oz. Diamine sky blue

F F, 1 lb. soda and 10 lb. Glauber's salt at the boil to shade.

_Red Violet._--Make the dye-bath with 1/2 lb. Diamine violet N, 1/2 oz.

Diamine brilliant blue G, 1 lb. soda and 10 lb. Glauber's salt, working

at the boil.

_Red Violet._--Dye with 1 lb. Diamine violet N, 1 lb. soda and 10 lb.

Glauber's salt.

_Bright Red Lilac._--Dye with 1-3/4 lb. Erika B N, 4 oz. Chicago blue 4

R, 3 lb. soda and 20 lb. Glauber's salt at the boil.

_Grey Lilac._--Dye with 12 oz. Neutral grey G, 3 oz. erika B N, 1 lb.

soda and 10 lb. Glauber's salt at the boil for one hour.

_Pale Lilac._--Dye with 2-1/2 oz. Dianil claret B, 2-1/2 oz. Dianil blue

4 R, and 10 lb. salt.

_Light Plum._--Dye with 10 oz. Dianil claret B, 10 oz. Dianil blue and

20 lb. salt.

_Dull Lilac._--Dye with 1/2 lb. Diamine brown V, 1 lb. soda and 10 lb.

Glauber's salt.

_Heliotrope._--Dye with 4 oz. Heliotrope 2 B, 1 lb. soda and 10 lb.

Glauber's salt.

_Plum._--Dye with 3 lb. Congo Corinth B, 3 lb. soda and 10 lb. Glauber's

salt.

_Dull Violet._--Use in the dye-bath 1-1/2 lb. Chicago blue 4 R, 14 oz.

Erika B N, 3 lb. soda and 20 lb. Glauber's salt, working at the boil for

one hour.

_Red Lilac._--Dye with 6 oz. Oxydiamine violet G, 2 oz. Oxydiamine

violet B, 1 lb. soda and 10 lb. Glauber's salt at the boil for one hour.

_Violet._--Dye with 3 oz. Diamine violet N, 2 oz. diamine blue 3 R, 1

lb. soda and 10 lb. Glauber's salt.

_Fawn Drab._--Prepare a dye-bath with 1 lb. Cachou de laval, 1/4 oz.

Benzo purpurine B. Enter the cotton into this bath in the cold and heat

to the boil, taking about one hour for the operation, then add 4 lb.

common salt and boil for three-quarters of an hour longer; lift, wash

and dry.

_Pale Olive Brown._--The dye-bath is made with 1 lb. Diamine bronze G, 1

oz. Cotton brown N, 3 oz. Diamine gold, 5 lb. soda, 15 lb. Glauber's

salt. Work at the boil for one hour, then lift, wash and dry.

_Red Brown._--Prepare a dye-bath with 1-3/4 lb. Cotton yellow, 4 lb.

Hessian brown 2 B N, 2 lb. Diamine black R O, 1 lb. soda, 2 lb. salt.

Enter the goods at 180° F., then raise to the boil and work to the

shade; lift, wash and dry.

_Brown Drab._--Prepare a dye-bath with 1/4 lb. Cotton brown N, 3/4 oz.

Diamine yellow N, 3/4 oz. Diamine black B O, 15 lb. phosphate of soda, 3

lb. soap. Work at the boil for one hour.

_Gold Brown._--Prepare the dye-bath with 16-1/4 oz. Toluylene orange G,

9-1/2 oz. Toluylene orange R, 4-3/4 oz. azo mauve, 2-1/2 lb. soap, 5 lb.

soda. Dye at the boil for one hour.

_Chestnut Brown._--Prepare a dye-bath with 10 lb. common salt, 2 lb.

Benzo brown G, 1/2 lb. Benzo azurine G, 1/2 lb. Chrysophenine. Enter the

goods at 150° F., raise to the boil and dye boiling for one hour.

_Purple Brown._--Prepare a dye-bath with 10 lb. common salt, 2 lb. Benzo

brown N B, 1 lb. Azo violet. Enter the cotton at 150° F., raise to the

boil and dye boiling for an hour; lift, wash and dry.

_Brown._--Prepare a dye-bath with 5 lb. soda, 10 lb. Glauber's salt, 12

oz. Chrysamine, 1 oz. Benzo purpurine, 6-1/4 oz. Benzo azurine. Dye at

the boil for one hour, rinse and dry. The brown thus got is fast to

washing.

_Dark Chestnut Brown._--Prepare a dye-bath with 10 lb. salt, 3 lb. Benzo

brown N B X, raise to 150° F., enter goods, heat to boil, and work for

one hour; lift, rinse and dry.

_Dark Brown._--Prepare a dye-bath with 20 oz. Glauber's salt per gallon

of water used, 2-1/2 lb. soap, 1-1/2 lb. Diamine black R O, 2 lb. Cotton

brown N. Enter the yarn at 180° F., give three turns, raise temperature

to boil, and work to shade; lift, rinse and wash.

_Gold Brown._--Prepare the dye-bath with 4 lb. Titan gold, 50 lb. salt.

Work at the boil for thirty minutes, then lift, wash and dry. The

dye-bath is not exhausted, only about 3 lb. of the colour being taken up

by the cotton. It may, therefore, be kept for further lots, adding 3 lb.

more colour and about 20 lb. more salt for each batch of cotton, or if

it is not desired to keep the bath, add less colour to start with, and

towards the end of the operation add more salt.

_Brown._--Prepare the dye-bath with 4 lb. Paramine brown G, 20 lb.

Glauber's salt, 2 lb. soda. Dye at the boil for one hour.

_Light Brown._--Prepare the dye-bath with 3 lb. Diamine catechine G, 3

lb. soda, 15 lb. Glauber's salt. Dye at the boil for one hour.

_Dark Brown._--Prepare the dye-bath with 5 lb. Diamine catechine B, 3

lb. soda, 15 lb. Glauber's salt. Dye at the boil for one hour.

_Dark Drab._--Prepare the dye-bath with 1 lb. Titan brown Y, 3 oz.

Columbia green, 32-3/4 oz. Diamine bronze, 17 lb. Glauber's salt. Work

at the boil for one hour, then lift, wash and dry.

_Pale Brown._--The dye-bath is made with 2 lb. Mikado orange 4 R, 3 oz.

Benzo fast grey, 30 lb. Glauber's salt. Work at the boil for one hour,

then lift, ash and dry.

_Gold Brown._--Make a dye-bath with 1 lb. Titan gold, 50 lb. common

salt. Enter at the boil, work for an hour, then lift, wash and dry. Keep

the bath for another lot of goods; it will only require the addition of

about 14 oz. of colour and 10 lb. salt.

_Buff Brown._--Make the dye-bath with 3/4 lb. Titan gold, 1/4 lb. Titan

brown R, 5 oz. Titan blue 3 B, 40 lb. common salt. Work at the boil to

shade, then lift, wash and dry.

_Deep Chestnut Brown._--Make the dye-bath with 3 lb. Titan brown R,

1-1/2 lb. Titan blue R, 25 lb. common salt. Work at the boil for an

hour, then lift, wash and dry.

_Light Seal Brown._--Make the dye-bath with 10 lb. salt, 2 lb. soda, 14

oz. Oxyphenine, 3/4 lb. Atlas red R, 6 oz. Diamine blue B X. Work at the

boil to shade, then lift, wash and dry.

_Orange Brown._--Make a dye-bath with 10 lb. salt, 2 lb soda, 14 oz.

Oxyphenine, 1 lb. Atlas red R, 1 oz. Diamine blue B X. Work at the boil

to shade, then lift, wash and dry.

_Pale Nut Brown._--Use in the dye-bath 4-1/2 oz. Diamine catechine G, 1

oz. Diamine brown M, 1 oz. Diamine catechine B, 2 lb. soda and 10 lb.

Glauber's salt, working at the boil for one hour.

_Walnut Brown._--Dye with 1 lb. Diamine brown M, 3 oz. Diamine orange G,

2 oz. Diamine black H W, 2 lb. soda and 10 lb. Glauber's salt at the

boil for one hour.

_Black Brown._--Use in the dye-bath 3 lb. Diamine brown M, 3/4 lb.

Diamine blue black R, 3 lb. soda and 20 lb. Glauber's salt, working at

the boil.

_Reddish Brown._--Dye with 2 lb. Dianil brown R, 5 lb. salt and 5 lb.

phosphate of soda at the boil for one hour.

_Chocolate Brown._--Dye with 2 lb. Dianil brown T, 5 lb. phosphate of

soda and 5 lb. salt at the boil for one hour.

_Dark Brown._--Dye with 2 lb. Dianil dark brown, 5 lb. salt and 5 lb.

phosphate of soda at the boil for one hour.

_Light Brown._--Prepare the dye-bath with 5 lb. Diamine catechine G, 3

lb. soda and 15 lb. Glauber's salt.

_Brown._--Dye with 2-1/4 lb. Cotton brown N, 4 oz. Diamine black H W, 2

lb. soda and 20 lb. Glauber's salt at the boil for one hour.

_Dark Walnut Brown._--Make the dye-bath with 3-1/4 lb. Diamine brown M,

6 oz. Diamine catechine B, 6 oz. Diamine red 5 B, 2 lb. soda and 20 lb.

Glauber's salt; work at the boil.

_Dark Chestnut Brown._--Dye with 2-1/2 lb. Dianil brown R, 1 lb. soda

and 20 lb. salt at the boil.

_Dark Brown._--Dye with 2 lb. Dianil brown 3 G O, 2 lb. Dianil brown B

D, 1 lb. Dianil red 4 B, 3 lb. soda and 25 lb. salt at the boil for one

hour.

_Brown._--Prepare the dye-bath with 5 lb. Mikado brown M and 25 lb.

salt; work the cotton in this at the boil for one hour.

_Nut Brown._--Use in the dye-bath 2-1/2 lb. Benzo brown G and 15 lb.

salt, working at the boil.

_Dark Brown._--Use in the dye-bath 3 lb. Benzo brown N B and 15 lb.

Glauber's salt, working at the boil.

_Dark Brown._--Make the dye-bath with 4 lb. Diphenyl brown B N, 10 lb.

Glauber's salt and 4 lb. soap, working at the boil to shade.

_Black Brown._--Use in the dye-bath 2-1/2 lb. Dianil brown 3 G O, 1-1/2

lb. Dianil brown G, 3/4 lb. Dianil dark blue R, 3 lb. soda and 25 lb.

salt.

_Dark Brown._--Dye with 1-1/2 lb. Zambesi black D, 1-1/4 lb. Brilliant

orange G, 3 lb. soda and 20 lb. Glauber's salt at the boil to shade.

_Gold Brown._--Dye with 2 lb. Curcumine S, 1 lb. Columbia orange R, 5

oz. Columbia black F B, 3 lb. soda and 15 lb. Glauber's salt at the

boil.

_Dark Chestnut._--Dye at the boil with 2 lb. Columbia Orange R, 8 oz.

Columbia black F B, 2 lb. soda and 10 lb. Glauber's salt.

_Sage Brown._--Dye with 1 lb. Zambesi black D, 1 lb. Curcumine S, 3/4

lb. Diamine orange G D, 3 lb. soda and 30 lb. Glauber's salt at the

boil.

_Deep Brown._--Dye 3-1/2 lb. Diamine brown M, 3/4 lb. Oxydiamine orange

G, 3/4 lb. Diamine black H W, 3 lb. soda and 20 lb. Glauber's salt at

the boil.

_Chestnut._--Dye with 2-1/2 lb. Diamine brown G, 3/4 lb. Oxydiamine

orange R, 3 lb. soda and 20 lb. Glauber's salt.

_Pale Walnut Brown._--Dye with 3-1/2 lb. Diamine brown M, 3/4 lb.

Oxydiamine orange G, 1-1/2 oz. Diamine black B H, 3 lb. soda and 20 lb.

Glauber's salt.

Various other browns may be obtained by combining the various direct

browns together or with other direct dyes. The use of a yellow or orange

will brighten them; that of a red will redden the shade; the addition of

a dark blue or a black will darken the shade considerably. It may be

useful to remember that a combination of red, orange and blue or black

produces a brown, and by using various proportions a great range of

shades can be dyed.

_Black._--Prepare a dye-bath with 6 lb. Diamine black R O, 2 oz.

Thioflavine S, 2 lb. soap, 10 lb. salt. Enter the cotton at the boil and

dye for one hour; lift, wash and dry.

_Black._--Prepare the dye-bath with 5 lb. Direct deep black E extra, and

1/2 to 1-1/2 oz. common salt per gallon of water. Dye at the boil for

one hour.

_Deep Black._--Prepare the dye-bath with 5-1/2 lb. Diamine deep black R

B, 2 lb. soda, 20 lb. Glauber's salt. Dye at the boil for one hour;

lift, wash and dry.

_Black._--Prepare the dye-bath with 5 lb. Direct triamine black G X, 15

lb. Glauber's salt. Dye for one hour at the boil; lift, rinse and dry.

In working for from two to three hours the dye-bath will exhaust

completely.

_Black._--Prepare the dye-bath with 5 lb. Oxydiamine black A, 20 lb.

Glauber's salt, 2 lb. soda. Dye at the boil for one hour.

_Black._--Prepare the dye-bath with 6 lb. Pluto black B. Dye at the boil

for one hour with the addition of 3/4 to 1-1/4 oz. Glauber's salt, 1/2

to 3/4 oz. soda ash per gallon of liquor. To develop the shade it is

necessary to dye in a boiling liquor.

_Black._--Use 2-1/2 lb. Diamine jet black Cr, 2-1/2 lb. Diamine jet

black R B, 2 lb. soda, and 20 lb. Glauber's salt, working at the boil

for one hour.

_Black._--Use 6 lb. Oxydiamine black N R, 2 lb. soda and 20 lb.

Glauber's salt, working at the boil for one hour.

_Black._--Use 6 lb. Columbia Black F B B, 3 lb. soda and 20 lb.

Glauber's salt, working at the boil to shade.

Besides the blacks given in the above recipes, there are other brands

which are used in the same way, and vary slightly in the shade of black

they give.

All the direct blacks require working in strong baths to give anything

like black shades; they all have, more or less, a bluish tone, which can

be changed to a jetter shade by the addition of a yellow or green dye in

small proportions, which has been done in one of the recipes given

above.

By coupling, chroming or developing, the direct blacks can be made to

give full, deep and fast blacks, and examples of their use in this

manner will be found in following sections.

By using all the direct blacks in proportions varying from 1/4 to 1 per

cent. of dye-stuff to the weight of the cotton they give greys of

various tints and depths; a few examples of such greys will now be

given.

_Blue Grey._--Prepare the dye-bath with 1/2 lb. Oxydiamine black A, 1

lb. soda, 10 lb. Glauber's salt. Dye at the boil for one hour.

_Bright Grey._--Prepare a dye-bath with 4-1/2 oz. Azo mauve A M, 1-1/2

oz. Direct yellow G, 3 lb. soda, 15 lb. common salt.

_Silver Grey._--Prepare the dye-bath with 1/2 oz. Neutral grey G, 10 lb.

sulphate of soda. Work at the boil to shade, then lift, wash and dry.

_Slate._--Dye in a bath with 1/2 lb. Diamine black B H, 3 oz. Diamine

bronze G, 15 lb. Glauber's salt at the boil for three-quarters of an

hour.

_Bronze Grey._--Prepare a dye-bath with 1/2 lb. Diamine bronze G, 15 lb.

Glauber's salt, 3 lb. soap. Enter at about 160° F., raise to boil and

work for one hour; lift, wash and dry.

_Dark Slate._--Prepare a dye-bath with 10 lb. Glauber's salt, 1-1/2 lb.

soap, 1 lb. Diamine black R O, 2 lb. Cotton brown N. Heat to about 150°

F. Enter the goods, work for a short time, then raise to the boil and

work for one hour; lift, wash and dry.

_Green Grey._--Prepare a dye-bath with 10 lb. Glauber's salt, 1 lb.

Diamine black R O, 3/4 oz. Thioflavine S. Enter at from 150° Tw. to 180°

F., raise to boil and dye for one hour; wash and dry.

_Light Slate._--Prepare a dye-bath containing 2-1/4 lb. soap, 15 lb.

Glauber's salt, 6 oz. Diamine black R O, 1/2 oz. thioflavine S. Enter

cotton at 140° F., work a little, then heat to boil and dye to shade;

lift, wash and dry.

_Grey._--Prepare the dye-bath with 1/2 lb. Diamine grey G, 1/2 oz.

Diamine scarlet B, 1 lb. soda, 1 lb. soap, 5 lb. Glauber's salt. Dye for

one hour at the boil.

_Light Grey._--Prepare the dye-bath with 1 lb. Diamine grey G, 1 lb.

soda, 1 lb. soap, 5 lb. Glauber's salt. Dye for one hour at the boil;

lift, rinse and dry.

It may be convenient here to deal with the question of the fastness of

the direct dyes to such influences as light, air, acids, alkalies,

washing and soaping, that have a very material influence on the use of

these dyes in dyeing various fabrics. This matter can only be dealt with

here in very general terms, for space is limited and the dyes are too

numerous for detailed mention. They vary very greatly in degrees of

fastness, some are absolutely fast to all influences; the blacks are

among the fastest, generally these resist washing and soaping, stand

acids well and are fast to alkalies, light however affects them more or

less, though they cannot be reckoned fugitive colours. The few direct

greens known are good colours; they stand washing, soaping and light

well, but they are affected by acids and alkalies. The blues vary very

much, generally they stand soaping and have a fair degree of fastness to

light, acids have but little action, alkalies tend to redden the shade,

while heat also affects them. The direct browns are very variable; they

are in general not fast to light; they stand washing and soaping and

resist alkalies, but are altered by acids slightly. The yellows rank

among the fastest of colours to light and washing and soaping; acids

have but little effect; they are reddened by alkalies. Among the reds

there is great variation in properties, generally they are not fast to

light, standing washing and soaping well and resisting weak alkalies;

some of them, such as the Benzo purpurines and Congo reds are very

sensitive to acids, being turned blue with very weak acids, but on

washing or soaping the original colour comes back; others, like the

Titan reds, Diamine reds and Delta purpurines are not so sensitive, but

these are affected by moderately strong acids; there are one or two reds

like Benzo fast scarlet 4 B S and Purpuramine D H, which are fast to

acids. The depth of shade which is dyed has some considerable influence

on the degree of fastness, the deeper shades of a colour are always

faster than the paler shades, particularly as regards light, a

difference of 1/2 per cent, of dye-stuff has been known to make a very

appreciable degree of difference as regards the fastness of a colour to

light.

In dyeing cotton with all the direct dyes, it is found that the whole of

the dye-stuff is not removed from the dye-bath, how much is taken up by

the cotton, and the depth of the shade which is dyed upon the cotton

chiefly depends upon three factors:--

(1) Volume of water used.

(2) Quantity of saline salts used.

(3) Degree of affinity of the dye-stuff for the fibre.

There may also be some minor factors such as temperature at which the

dyeing is carried on, the character and condition of the fabrics being

dyed, etc.

The volume of water used in making the dye-bath has a very great

influence upon the amount of dye taken up by the cotton, the greater the

volume of water the less dye is absorbed and the paler the colour which

is produced upon the fibre. It is therefore important to use as little

water as possible in making up the dye-bath, indeed, for anything like

good results to be obtained with some dyes, especially those of the

sulphur series like Vidal black, Immedial blacks, Katigen browns,

Cross-dye blacks, Amidazol blacks, etc., it is necessary to employ what

is called a short bath, that is making it as strong as possible. The

proportion of water with such dyes should not exceed fifteen times the

weight of the cotton being dyed, that is, for every pound of cotton,

1-1/2 gallons of water can be allowed. This will suit the dyeing of

yarns and loose fabrics like knitted stockings and hosiery goods very

well. In the case of dyeing piece goods on a jigger or continuous dyeing

machines even stronger liquors can be used with advantage. With some of

the older, direct dyes like Congo red, Benzo azurine, Diamine scarlets,

the proportion of water may be increased to twenty times the weight of

the cotton. In any case the quantity of water used should not exceed

twenty-five times the weight of the cotton.

The second factor, the quantity of saline salts, like Glauber's salt,

soda, borax, etc., added in the dyeing, is not without influence,

generally the more that is added the more dye there is left in the bath,

but here again much depends upon the salt and the colouring matters

used. Some salts, more particularly Glauber's salt and common salt, tend

to throw some dye-stuffs out of the bath, and so the more there is used

of them the deeper the shade produced on the fabric. It is quite

impossible, having regard to the scope of this book, to deal with this

question in detail. The dyer should ascertain for himself the best salts

and the best proportions of these to use with the particular dyes he is

using. The recipes given above will give him some ideas on this point.

The third factor, the degree of affinity of the dye for the cotton

fibre, has some influence on the depth of shade which can be dyed from

any given strength of the dye-bath. There is a very considerable

difference among the direct dyes in this respect. There are some which

have a fair degree of affinity, while there are others which have but

little affinity, and while in the former case there is little dye left

in the bath, in the latter case there is a good deal. When dyeing plain

shades with single dye-stuffs this is not of much moment, because if the

bath be kept for further use, as will be spoken of presently, the bath

may be brought up to its original strength by adding a proportionate

amount of dye-stuff, but when compound shades are being dyed, using two

or more dyes, then this feature has some influence, for they will not be

absorbed by the fibre in the same proportion as they were put in the

bath, and so when making up the dye-bath for the second lot, and adding

the same proportion of dyes, the shade which is produced will not be

quite the same, for the first lot of cotton in taking up the dyes in

varying quantities has altered their relative proportions, and so the

bath for the second lot of cotton will actually contain more of one dye

than did the first bath, and the influence of this excess of the one

constituent will show itself in the shade ultimately dyed. The more lots

of cotton there are dyed in the bath the greater will this influence be.

The dyer must by practical experience find out for himself in what

direction this feature of the direct dyes exerts its influence on the

particular dyes he is working with and make due allowance.

It is found in practice that from one-fourth to one-half of the original

weight of dye-stuff is left in the bath, and in order to be as

economical as possible a custom has arisen of keeping the bath and using

it again for dyeing further lots of cotton. In thus making a continuous

use of dye-baths it is important in preparing the baths for the next lot

of cotton to add first the requisite quantities of dye-stuffs, how much

will depend upon the factors and conditions already detailed, but from

one-half to three-fourths of the original quantities are added.

Practical experience alone is the guide to be followed.

Having added the dye-stuff, then sufficient water must be added to bring

up the volume of the bath to the proper amount, for it will have lost

some. The loss of water arises from two sources: first there is the

evaporation, which always occurs when dye-baths are heated up, and,

second, there is the mechanical loss due to its absorption by the

material which is being dyed. When a piece of cotton or other textile

fabric is immersed in a dye liquor it absorbs mechanically some of it,

and this amount may be roughly put down as about its own weight; thus

100 lb. weight of cotton will take up 10 gallons of liquor and carry

that quantity out of the bath. To some extent this may be minimised by a

previous wetting out of the cotton, which will then have in it as much

liquor as it will take up, and so practically no more will be taken up

from the dye-bath. Any loss of volume which may thus occur can be

remedied by the addition of water.

The dye-baths containing in solution, in addition to the dye-stuff,

salt, or Glauber's salt, or any other added substance, the cotton in

taking up the dye liquor will of course take up some of these in

proportion to the volume of liquor absorbed. The amount may range from 4

oz. to 1 lb. per gallon of liquor, and if 100 lb. cotton is being dyed

and takes up from 10 to 15 gallons of liquor, it is obvious that it must

absorb from 3 to 10 lb. of saline matter, and as the salinity of the dye

liquor is of some importance in dyeing direct colours, in making up the

bath for the next lot of cotton this must be allowed for and suitable

additions made. In order to do this properly it is a good plan to rely

upon the Twaddell.

The dyer should take the Twaddell of his bath before use and always make

up his baths to that strength. This will be found to range from 3° to

12° Tw.

Thus, for instance, a dye-bath made from 120 gallons of water with 20

lb. to 25 lb. common salt or Glauber's salt with the dye-stuffs will

stand at 4° Tw., one made with 50 lb. common salt or Glauber's salt at

8° Tw., while one which is made with 80 lb. to 100 lb. salt will stand

at 12° to 13° Tw. If the dyer always maintains his liquors at one

uniform degree Twaddell he can invariably depend upon getting uniform

shades from his dye-baths. This uniform strength is attained by adding

more salt or more water as the case may require.

Of course the continuous working of dye-baths cannot go on for ever;

sooner or later the baths become thick and dirty, and then they must be

thrown away and a new bath started.

(2) DIRECT DYEING FOLLOWED BY FIXATION WITH METALLIC SALTS.

It is an acknowledged principle in dyeing that to produce colours fast

to washing, soaping and rubbing, there must be produced on the fibre an

insoluble coloured substance. Now as the direct dyes do not essentially

produce such insoluble bodies when dyed on the cotton, the colours they

form are not always fast to washing and soaping. It has been

ascertained, however, that some of the direct dyes, _e.g._, Benzo

azurine, Chicago blue, Catechu browns, Diamine blues, Diamine browns,

etc., are capable of uniting with metallic bodies to form insoluble

colour lakes, and this combination can take place on the fibre. Fast

shades may be dyed with the dye-stuffs named above, and with others of

this group, by first dyeing them in the usual way, then passing through

a boiling bath containing bichromate of potash or copper sulphate,

either together or separately. The two fixing agents here named have

been found to be the best, although others, as, for instance, zinc

sulphate, chromium fluoride and iron sulphate have been tried. With some

dyes there is little or no alteration in shade, but in others there is

some change, thus the blues as a rule tend to become greener in tone,

and browns also tend to acquire a greener tone and deeper shade. The

treated shades thus obtained are notable for considerable fastness to

washing, soaping and light. It is to be noted that bichromate of potash

exercises both a fixing and an oxidising action on dye-stuffs, hence it

is needful to use it with some degree of caution and not in too great an

amount, otherwise with some dyes there is a risk of over-oxidation, and

in consequence poor shades will be developed. The following recipes will

serve to show what dyes may thus be used, and the colours that can be

obtained with them.

_Dark Red._--Use in the dye-bath 3 lb. Diamine fast red F, 3 lb. soda

and 20 lb. Glauber's salt, work at the boil for one hour, then lift,

rinse and pass into a boiling bath containing 3 lb. fluoride of chromium

for ten to fifteen minutes, then lift, rinse and dry. By using 1 lb. of

the dye-stuff in the same way a light red shade is got.

_Orange._--Dye at the boil for one hour with 1 lb. Chrysamine G, 3 lb.

soap and 10 lb. Glauber's salt, then rinse and fix in a fresh boiling

bath with 1 lb. bichromate of potash, 3 lb. sulphate of copper and 2 lb.

acetic acid.

_Yellow._--Dye with 3-1/2 lb. Diamine yellow N, 3 lb. soap and 15 lb.

phosphate of soda, then fix with 4 lb. fluoride of chromium.

_Gold Yellow._--Prepare the dye-bath with 3 lb. Benzo chrome brown 5 G,

1 lb. soda ash, 12 lb. Glauber's salt. Dye at the boil for one hour and

rinse. This gives an orange brown. To get the yellow shade, afterwards

chrome with 3 lb. bichromate of potash, 3 lb. sulphate of copper, 1 lb.

acetic acid, in a fresh bath. Enter at about 130° F., bring to the boil,

and boil for half an hour.

_Pale Leaf Green._--Dye with 3 lb. Dianil yellow 3 G, 1 lb. Dianil

yellow R, 1 lb. Dianil blue G, and 20 lb. salt, then fix with 3 lb.

copper sulphate and 2 lb. acetic acid.

_Leaf Green._--Dye with 3 lb. Dianil yellow 3 G, 3 lb. Dianil blue G,

and 20 lb. salt, fixing with 4 lb. copper sulphate and 2 lb. acetic

acid.

_Dark Green._--Dye with 2 lb. Dianil yellow R, 1-1/2 lb. Dianil dark

blue R, 1 lb. soda and 20 lb. salt, fixing with 3 lb. copper sulphate.

_Pale Olive Green._--Dye with 2-3/4 lb. Diamine fast yellow B, 1-1/4 lb.

Diamine blue R W, 3/4 lb. Diamine blue R W, 3/4 lb. Diamine catechine G;

fix with 4 lb. sulphate of copper and 2 lb. acetic acid.

_Russia Green._--Dye with 2-1/2 lb. Diamine blue R W, 10 oz. Diamine

dark blue B, 2-1/2 lb. Diamine fast yellow B, 3 lb. soda and 20 lb.

Glauber's salt; fix with 4 lb. sulphate of copper and 2 lb. acetic acid.

_Blue Green._--Dye with 1-3/4 lb. Diamine sky blue F F, 6 oz. Diamine

fast yellow B, 1 lb. soda and 10 lb. Glauber's salt; fix with 2 lb.

sulphate of copper and 1 lb. acetic acid.

_Bronze Green._--Use in the bath at the boil 4 lb. Diamine bronze G, 2

lb. soda and 10 lb. Glauber's salt, then fix with 4 lb. fluoride of

chromium.

_Pea Green._--Dye in a boiling bath with 1/2 lb. Diamine sky blue F F,

2-1/4 lb. Diamine fast yellow A, 1 lb. soda and 10 lb. Glauber's salt,

then fix in a fresh bath with 2 lb. sulphate of copper and 1 lb. acetic

acid.

_Leaf Green._--Dye at the boil for one hour in a bath containing 2-3/4

lb. Diamine fast yellow B, 1-3/4 lb. Diamine blue R W, 7 oz. Diamine

catechine B, 2 lb. soda and 20 lb. Glauber's salt, then fix in a new

bath with 4 lb. sulphate of copper and 2 lb. acetic acid.

_Light Green._--Prepare the dye-bath with 7-1/4 oz. Diamine blue R W,

5-1/2 oz. Diamine orange B, 2 lb. Diamine fast yellow B, 1 lb. soda and

10 lb. Glauber's salt, work at the boil for one hour, then treat in a

fresh bath with 3 lb. sulphate of copper.

_Olive Green._--Dye with 2-1/4 lb. Chicago blue R W, 15 oz. Chrysamine

G, 2 lb. soda and 10 lb. Glauber's salt; fix with 1 lb. bichromate of

potash, 3 lb. sulphate of copper and 2 lb. acetic acid.

_Pea Green._--Use in the dye-bath 3 lb. Chrysophenine G, 1 lb. Chicago

blue 6 B, 2 lb. soda and 10 lb. Glauber's salt, working at the boil for

one hour, then fix in a fresh boiling bath with 3 lb. sulphate of copper

and 2 lb. acetic acid.

_Green._--Dye with 2-3/4 lb. Chicago blue 6 B, 5 oz. Chrysamine G, 2 lb.

soap and 20 lb. Glauber's salt; fix with 1 lb. bichromate of potash, 3

lb. sulphate of copper and 2 lb. acetic acid.

_Dark Green._--Dye with 1-1/2 lb. Diamine green B, 1-1/2 oz. Diamine

bronze G, 1 lb. Diamine fast yellow A, 3 lb. soda and 20 lb. Glauber's

salt, working at the boil for one hour, then lift, rinse and fix in a

fresh boiling bath with 3 lb. fluoride of chromium for one to fifteen

minutes.

_Dark Bronze._--Use in the dye-bath 2-1/2 lb. Diamine bronze G, 3 lb.

soda and 20 lb. Glauber's salt, working at the boil for one hour, then

lift, rinse and fix with 3 lb. fluoride of chromium as above.

_Dark Blue._--Prepare the dye-bath with 3 lb. Benzo blue R W, 10 lb.

Glauber's salt; dye for one hour at the boil, then treat in fresh bath

with 1 lb. sulphate of copper at the boil for half an hour.

_Blue._--Dye with 1-3/4 lb. Diamine brilliant blue G, 1-1/4 lb. Diamine

sky blue F F, 2 lb. soda and 20 lb. Glauber's salt; fix in a bath with 4

lb. sulphate of copper and 2 lb. acetic acid.

_Light Navy._--Dye with 1 lb. Diamine blue 3 R, 2-1/4 lb. Diamine blue R

W, 2 lb. soda and 20 lb. Glauber's salt; fix with 4 lb. sulphate of

copper and 20 lb. acetic acid.

_Bright Navy._--Dye with 4 lb. Diamine brilliant blue G, 2 lb. soda and

20 lb. Glauber's salt; fix with 4 lb. sulphate of copper and 2 lb.

acetic acid.

_Blue._--Dye with 3 lb. Chicago blue R W, 3 lb. soda and 20 lb.

Glauber's salt; fix with 3 lb. sulphate of copper and 2 lb. acetic acid.

_Dark Blue._--- Dye with 3 lb. Chicago blue R W, 1-1/2 lb. Zambesi black

F, 3 lb. soda and 20 lb. Glauber's salt; fix with 3 lb. sulphate of

copper and 2 lb. acetic acid.

_Deep Slate Blue._--Dye with 1-1/4 lb. Zambesi black F, 1-1/4 lb.

Chicago blue B, 6 oz. Columbia yellow, 3 lb. soda and 20 lb. Glauber's

salt; fix with 3 lb. sulphate of copper and 2 lb. acetic acid.

_Light Blue._--Prepare the dye-bath with 2 oz. Diamine sky blue F F,

3/4 oz. Diamine fast yellow A, 1/2 lb. soda, 2 lb. soap and 5 lb.

Glauber's salt; dye for one hour at the boil, then treat in a fresh bath

with 1-1/2 lb. sulphate of copper for half an hour.

_Dark Blue._--Prepare the dye-bath with 4 lb. Benzo chrome black blue B,

15 lb. Glauber's salt and 3 lb. soda. Work at the boil for one hour,

then chrome in a fresh bath with 1 lb. bichromate of potash, 1 lb.

sulphate of copper and 1/2 lb. sulphuric acid.

_Dark Blue._--Dye with 2-1/2 lb. Diamineral blue R, 3 lb. soda and 20

lb. Glauber's salt; fix with 2 lb. sulphate of copper, 2 lb. bichromate

of potash and 2 lb. acetic acid.

_Turquoise Blue._--Dye with 1 lb. Chicago blue 6 B, 2 lb. soda and 10

lb. Glauber's salt, and fix with 3 lb. sulphate of copper and 2 lb.

acetic acid.

_Dark Turquoise Blue._--Dye with 3 lb. Chicago blue 4 B, 2 lb. soda and

10 lb. Glauber's salt, and fix with 3 lb. sulphate of copper and 2 lbs.

acetic acid.

_Black Blue._--Dye with 4-1/4 lb. Diamine dark blue B, 1 lb. Diamine new

blue R, 2 lb. soda and 10 lb. Glauber's salt, fixing with 5 lb. sulphate

of copper and 2 lb. acetic acid.

By mixing together the various Diamine blues a very great range of

shades can be produced, from pale sky-blue tints to the deepest of

blues.

_Bright Blue._--Dye with 2-1/4 lb. Dianil blue B and 20 lb. Glauber's

salt; fix with 3 lb. of fluoride of chromium.

_Dark Blue._--Dye with 3 lb. Dianil blue B, 1 lb. Dianil dark blue R, 1

lb. soda and 20 lb. salt, fixing with 3 lb. fluoride of chromium.

_Red Violet._--Dye with 1 lb. Dianil blue 4 R and 10 lb, salt, fixing

with 4 lb. fluoride of chromium.

_Dark Plum._--Dye with 3 lb. Dianil blue 4 R and 15 lb. salt, fixing

with 4 lb. fluoride of chromium.

_Red Violet._--Dye with 1 lb. Diamine blue 3 R, 1 lb. soda and 10 lb.

Glauber's salt, fixing with 1-1/2 lb. sulphate of copper and 1 lb.

acetic acid.

_Red Plum._--Use 3-3/4 lb. Diamine blue 3 R, 3 lb. soda and 20 lb.

Glauber's salt, fixing with 5 lb. sulphate of copper and 2 lb. acetic

acid.

_Dark Brown._--Prepare the dye-bath with 5 lb. Diamine catechine B, 3

lb. soda and 15 lb. Glauber's salt and dye at the boil for one hour,

then treat with 2 lb. sulphate of copper and 2 lb. bichromate of potash.

_Brown._--Prepare the dye-bath with 4 lb. Paramine brown C, 20 lb.

Glauber's salt, 2 lb. soda and dye at the boil for one hour; treat with

3 lb. copper sulphate.

_Light Brown._--Dye at the boil for one hour in a bath containing 5 lb.

Diamine catechine G, 3 lb. soda and 15 lb. Glauber's salt, then treat in

a fresh bath with 2 lb. sulphate of copper and 2 lb. bichromate of

potash.

_Dark Chestnut Brown._--Dye for an hour in a boiling bath with 2-1/4 lb.

Diamine catechine G, 1-1/4 lb. Diamine fast yellow B, 3 lb. soda and 20

lb. Glauber's salt; then fix in a fresh boiling bath with 2 lb. sulphate

of copper, 2 lb. bichromate of potash and 2 lb. acetic acid, working for

fifteen to twenty minutes, then rinsing and drying.

_Brown._--Use 3 lb. Catechu brown G K, 15 lb. Glauber's salt and 1/2 lb.

soap; after dyeing for one hour at the boil treat in a fresh boiling

bath with 3 lb. copper sulphate.

_Dark Brown._--Dye at the boil for one hour with 3 lb. Catechu brown F

K, 15 lb. Glauber's salt and 1 lb. soap, then treat in a fresh boiling

bath with 3 lb. copper sulphate.

_Brown._--Prepare the dye-bath with 9 oz. Diamine blue R W, 12-1/2 oz.

Diamine orange B, 1-3/4 lb. Diamine fast yellow B, 2 lb. soda and 20 lb.

Glauber's salt; after working for one hour at the boil treat in a fresh

boiling bath with 4 lb. sulphate of copper.

_Brown._--Prepare the dye-bath with 4 lb. Benzo chrome brown 2 R, 20

lb. Glauber's salt (crystals) and dye at the boil for one hour;

afterwards treat with bichromate of potash and sulphate of copper.

_Nut Brown._--Dye in a bath with 4 lb. Benzo chrome brown G and 20 lb.

salt, then treat in a fresh bath with 4 lb. bichromate of potash, 4 lb.

copper sulphate and 1 lb. acetic acid.

_Chestnut Brown._--Dye at the boil for one hour in a bath containing 4

lb. Benzo chrome brown R, and boiling bath with 4 lb. bichromate of

potash, 4 lb. sulphate of copper and 1 lb. acetic acid.

_Dark Olive Brown._--Dye with 4 lb. Diamine bronze G, 1 lb. Diamine

orange B, 2 lb. soda and 20 lb. Glauber's salt; fix with 5 lb. sulphate

of copper and 2 lb. acetic acid.

_Deep Brown._--Use in the Dye-bath 1-3/4 lb. Diamine brown B, 1-3/4 lb.

Diamine fast yellow B, 1/2 oz. Diamine black B H, 3 lb. soda and 20 lb.

Glauber's salt. The fixing bath contains 2 lb. sulphate of copper, 2 lb.

bichromate of potash, and 2 lb. acetic acid.

_Dark Brown._--Dye with 2 lb. Diamine brown M, 1 lb. Diamine fast red F,

1/2 lb. Diamine jet black Cr, 3 lb. soda and 20 lb. Glauber's salt. The

fixing bath contains 2 lb. sulphate of copper, 2 lb. bichromate of

potash and 2 lb. acetic acid.

_Black Brown._--Dye with 1-3/4 lb. Diamine dark blue B, 3/4 lb. Diamine

orange B, 1-3/4 lb. Diamine fast yellow B, 2 lb. soda and 20 lb.

Glauber's salt, fixing with 5 lb. sulphate of copper and 2 lb. acetic

acid.

_Light Sage Brown._--Dye with 3/4 lb. Diamine brown B, 1-1/2 lb. Diamine

fast yellow B, 3 oz. Diamine dark blue B, 2 lb. soda and 20 lb.

Glauber's salt, fixing with 3 lb. sulphate of copper and 1 lb. acetic

acid.

_Pale Brown._--Use in the dye-bath 1 lb. Dianil brown 3 G O, 4 oz.

Dianil brown E, 4 oz. Dianil black N, 1 lb. soda and 20 lb. salt,

fixing with 1-1/2 lb. sulphate of copper and 1 lb. acetic acid.

_Walnut Brown._--Dye with 2-1/2 lb. Diamine blue 3 R, 1 lb. Diamine

brown M, 2 lb. soda and 20 lb. Glauber's salt, then fix with 5 lb.

sulphate of copper and 2 lb. acetic acid.

_Pale Fawn Brown._--Dye with 2 lb. Diamine blue 3 R, 1 lb. Diamine brown

M, 2 lb. soda and 20 lb. Glauber's salt, then fix with 5 lb. sulphate of

copper and 2 lb. acetic acid.

_Pale Fawn Brown._--Dye with 1/2 lb. Diamine orange B, 1/4 lb. Diamine

fast yellow B, 1 lb. soda and 10 lb. Glauber's salt, fixing with 2 lb.

sulphate of copper and 1 lb. acetic acid.

_Sage Brown._--Dye with 9 oz. Diamine blue R W, 3/4 lb. Diamine orange

B, 1-3/4 lb. Diamine fast yellow B, 2 lb. soda and 20 lb. Glauber's

salt. The fixing is done with 4 lb. sulphate of copper and 2 lb. acetic

acid.

_Red Chocolate._--Dye with 3 lb. Diamine orange B, 1 lb. soda and 10 lb.

Glauber's salt; fix with 2 lb. sulphate of copper and 1 lb. acetic acid.

_Dark Chestnut._--Dye with 2-1/2 lb. Dianil brown 3 G O, 13 oz. Dianil

brown R, 13 oz. Dianil brown B D, 1 lb. soda and 20 lb. salt, fixing

with 3 lb. copper sulphate and 1 lb. acetic acid.

_Brown._--Dye with 2-1/4 lb. Chrysophenine G, 1-1/4 lb. Diamine brown G,

1-1/4 lb. Chicago blue R W, 3 lb. soda and 20 lb. Glauber's salt; fix

with 3 lb. sulphate of copper and 2 lb. acetic acid.

_Nut Brown._--Dye with 3 lb. Chromanil brown 2 G, 3 lb. soda and 20 lb.

Glauber's salt; fix with 1 lb. bichromate of potash, 3 lb. sulphate of

copper and 2 lb. acetic acid.

_Dark Grey._--Dye at the boil for one hour with 1 lb. Zambesi black F, 3

lb. soda and 10 lb. Glauber's salt; fix in a fresh boiling bath with 3

lb. sulphate of copper, 1 lb. bichromate of potash and 10 lb. Glauber's

salt.

_Dark Grey._--Dye with 3 lb. Chromanil black 4 R F, 3 lb. soda and 10

lb. Glauber's salt; fix with 1 lb. bichromate of potash, 3 lb. sulphate

of copper and 2 lb. acetic acid.

_Dark Grey._--Use in the dye-bath 1 lb. Diamine blue R W, 1/2 lb.

Diamine orange B, 1/4 lb. Diamine new blue R, 2 lb. soda and 20 lb.

Glauber's salt, fixing with 4 lb. sulphate of copper and 2 lb. acetic

acid.

_Pale Greenish Grey._--Dye with 1/4 oz. Diamine orange B, 3 oz. Diamine

blue R W, 1/2 lb. soda, 2 lb. soap and 5 lb. Glauber's salt, fixing with

1 lb. sulphate of copper and 1/2 lb. acetic acid.

_Slate Blue._--Dye with 1/4 lb. Diamine dark blue B, 2 oz. Diamine new

blue R, 1 lb. soda and 10 lb. Glauber's salt; fix with 2 lb. sulphate of

copper and 1 lb. acetic acid.

_Grey._--Prepare the dye-bath with 2 lb. Cross-dye black 2 B, 5 lb. soda

ash, 15 lb. common salt; after rinsing leave the cotton in the air to

age overnight, rinse again and work for half to three-quarters of an

hour at from 150° to 160° F. in a bath containing 5 lb. bichromate of

potash and 5 lb. sulphuric acid, then thoroughly rinse and dry.

_Dark Grey._--Dye with 1 lb. Diamine jet black Cr, 1 lb. soda and 10 lb.

Glauber's salt, fixing with 1 lb. bichromate of potash and 1/2 lb.

acetic acid.

_Green Grey._--Dye with 1 lb. Diamine dark blue B, 2 oz. Diamine orange

B, 4 oz. Diamine fast yellow B, 1 lb. soda and 10 lb. Glauber's salt,

fixing with 3 lb. sulphate of copper and 1 lb. acetic acid.

_Grey._--Dye with 4 oz. Dianil black N, 1 lb. soda and 10 lb. salt,

fixing with 1 lb. copper sulphate and 1/2 lb. acetic acid.

_Black._--Prepare the dye-bath with 5-1/2 lb. Diamine jet black R B, 1

lb. Diamine dark blue B, 20 lb. Glauber's salt; dye at the boil for one

hour, rinse and then treat the goods simmering for twenty minutes with 4

lb. bichromate of potash.

_Black._--Prepare the dye-bath with 8 lb. Chromanil black R F and 20 lb.

Glauber's salt; dye at the boil for one hour, then treat boiling hot for

about thirty minutes in a fresh bath with 1 lb. bichromate of potash

and 3 lb. sulphate of copper. Add 6 lb. only of the dye-stuff to the

bath for a second batch.

_Black._--Use 5 lb. Dianil black N, 5 lb. soda and 20 lb. salt; then fix

with 3 lb. copper sulphate, 3 lb. bichromate of potash and 2 lb. acetic

acid.

_Black._--Use in the dye-bath 5 lb. Dianil black C R. 3 lb. caustic

soda, 36° Tw. and 20 lb. salt, fixing with 3 lb. copper sulphate, 3 lb.

bichromate of potash and 2 lb. acetic acid.

_Jet Black._--Dye with 5 lb. Diamine jet black Cr, 1 lb. soda and 20 lb.

Glauber's salt, fixing with 4 lb. bichromate of potash and 2 lb. acetic

acid.

It will be convenient here to deal with a small but growing and

important class of dye-stuffs which contain sulphur in their

composition, and which, therefore, are named:--

=Sulphur or Sulphyl Colours.=

The original type of this group is Cachou de laval, sent out a good many

years ago, but of late years Vidal black, St. Dennis black, Cross-dye

blacks and drab, Immedial blacks, blues and browns, Amidazol blacks,

browns and olives, Sulfaniline black and brown, Katigen blacks, greens

and browns, etc., have been added, and the group is likely to become a

very numerous one in the future.

All these colours are dyed on to the cotton or linen from baths

containing soda and salt, while some require the addition of sodium

sulphide or caustic soda in order to have the dye-stuff properly

dissolved. They are very weak dyes compared with the direct colours, and

require from 20 to 60 per cent. to produce full shades, although of this

fully one-third remains in the bath unabsorbed by the cotton. It is,

therefore, important in order to work as economically as possible to

retain the bath, bringing it up to strength by the addition of fresh

dye-stuffs, etc.

Most of the dyes require the dyed goods to pass through a second bath of

some reagent, bichromate of potash, sulphate of copper, etc., in order

to fully develop and fix the dye on the fabric.

The best method of using the various dyes of this group will be given in

the form of formulæ. Two points of importance are to use as strong a dye

liquor as possible, and to expose the cotton as little as possible to

the air during the dyeing operation. The dye-stuffs when exposed to the

air readily become oxidised, and are thereby converted into insoluble

products which become fixed on the fibre in a loose form, and in that

case the dyed fibre rubs rather badly.

_Pale Brown._--Prepare a dye-bath with 15 lb. Cachou de laval, 10 lb. of

soda, and 10 lb. salt. The bath is not exhausted of colouring matter,

and by adding one-half of the above quantities of dye-stuff and salt may

be used again for another lot of cotton. After the dyeing the cotton is

passed into a fixing bath of 2 lb. bichromate of potash and 1 lb. acetic

acid, working at 180° F. ten to fifteen minutes.

_Black._--Prepare the dye-bath with 200 gallons of water, 10 lb. soda,

10 lb. sulphide of sodium, 60 lb. salt and 16 lb. Immedial black V

extra. Work at the boil for one hour, keeping the cotton well under the

surface during the operation, in the case of yarns this is effected by

using bent iron rods on which to hang the hanks in the vat, in the case

of pieces by working with vats the guide rollers of which are below the

surface of the dye liquor. After the dyeing the yarn or pieces are

squeezed, well rinsed in water, then passed into the fixing bath, which

contains 2 lb. sulphate of copper, 2 lb. bichromate of potash and 3 lb.

of acetic acid, for half an hour at 170° to 180° F. Bichromate of potash

used alone gives a reddish shade of black, sulphate of copper a greenish

shade, a mixture of the two gives a greenish shade.

There are three brands of Immedial black, _viz._, V extra, G extra and

F F, which vary a little in the tone of black they produce. The method

of using is identical for all three. The dye-bath is not exhausted of

colour and so should be kept standing, for each subsequent lot of cotton

add 8 lb. Immedial black and 3 lb. sulphide of soda, and to every 10

gallons of water added to bring the bath up to volume 1/2 lb. soda and 3

lb. salt.

These blacks are very fast to washing, light, etc. By using smaller

quantities of dye-stuff good greys can be dyed.

_Black._--Prepare the dye-bath with 10 lb. soda, 10 lb. sulphide of

sodium, 60 lb. salt and 25 lb. Vidal black, work at the boil for one

hour, then rinse and fix with 3 lb bichromate of potash and 2 lb.

sulphuric acid.

_Black._--Prepare the dye-bath with 30 lb. Cross-dye black B, 10 lb.

soda, 150 lb. salt. Dissolve the dye-stuff in boiling water, then add

the soda crystals and finally the salt. Enter the previously well-boiled

cotton at about 175° F. After a few turns raise the temperature to the

boil as quickly as possible, and work for one hour (just at the boil).

Lift and thoroughly rinse without delay. (The better the cotton is

washed the clearer the ultimate shade.) After washing, wring up and let

air age for about one hour; the intensity of the black is thereby

increased.

Meanwhile prepare a bath with 5 lb. bichromate of potash, 4 lb.

sulphuric acid (168° Tw.). Enter at 150° to 160° F., and work at this

for about ten minutes. After chroming, wash thoroughly to remove all

traces of acid. At this stage, the usual softening may take place if

desirable, and finally dry at a low temperature.

The bath is kept up for further lots, and three-fourths the quantity of

colouring matter, and about half soda and one fourth salt are used.

Wood, or iron cisterns are most suitable, and copper pans or pipes must

be avoided.

The dye-bath should be kept as short as possible, about twelve to

fifteen times the amount of water on the weight of cotton is advisable.

The cotton when in the dye-bath should be exposed as little as possible

to the air.

There are several brands of these Cross-dye blacks varying in the tone

of black they give.

_Black._--Prepare the dye-bath with 5 lb. soda ash, 200 lb. salt and 20

lb. Amidazol black G, this is heated to 150° F., the cotton is entered,

the heat raised to the boil, and the dyeing done for an hour at that

heat. Lift, rinse well, then pass into a chroming bath, made from 5 lb.

bichromate of potash and 3 lb. sulphuric acid, used at 160° F. for

twenty minutes, then lift, wash well and dry. The bath may be kept

standing and used for other lots of cotton by replenishing with about

two-thirds of the original weight of dye-stuff and a little soda. There

are four brands of these Amidazol blacks which dye from a jet black with

the G to a deep blue black with the 6 G brand. The G, 2 G, and 4 G, used

in small quantities, 2-1/2 to 3 lb., dye good greys of a bluish tone,

the 6 G gives a dull blue, the 4 G and 6 G, used in the proportions of

7-1/2 to 10 per cent., give dark blues.

All these blacks may be combined with aniline black with good results as

shown in the following recipe:--

_Black._--Prepare the dye-bath with 10 lb. Amidazol black 2 G, 5 lb.

soda and 100 lb. salt. Work at the boil for an hour, then rinse, pass

into a cold bath made from 2-1/2 lb. aniline oil, 2-1/2 lb. hydrochloric

acid, 6-1/2 lb. sulphuric acid, 7-1/2 lb. bichromate of potash, and

5-1/2 lb. perchloride of iron, 66° Tw. This is used cold for an hour,

then the heat is slowly raised to 160° F., when the operation is

finished, and the cotton is taken out well rinsed and finished as usual.

Any of this class of black may be so topped with aniline black if

thought necessary A very fast black is thus got.

_Black._--Make the dye-bath with 15 lb. Sulfaniline black G, 60 lb.

salt, 10 lb. soda, and 5 lb. sulphide of sodium. Work at a little under

the boil, then lift, rinse well and pass into a hot bath of 3 lb.

bichromate of potash, 3 lb. sulphate of copper, and 4 lb. acetic acid

for half an hour, then lift, rinse well and dry.

It has been observed in the practical application on a large scale of

these sulphur blacks that the cotton is liable to become tendered on

being stored, although there are few signs of such after the dyeing is

finished. The exact cause of this is somewhat uncertain, the most

probable reason is that during the process of dyeing a deposit of

sulphur in a fine state of division has been thrown down on the cotton

by decomposition of the dye-stuff, and that this sulphur has in time

become oxidised to sulphuric acid which then exerts its well-known

tendering action on the cotton.

The remedy for this evil lies partly with the dye manufacturer and

chiefly with the dyer. The dye manufacturer should see that his product

is made as free from sulphur as possible, while the dyer by careful

attention to thorough washing, thorough fixation in the chrome, etc.

baths, tends to eliminate all sulphur from the goods, and so prevent all

possibility of the cotton becoming affected.

_Blue._--Make the dye-bath with 22 lb. Immedial blue C, 13 lb. sulphide

of sodium, 50 lb. salt and 15 lb. caustic soda lye at 70° Tw. Work at

just under the boil for one hour, keeping the goods well under the

surface of the liquor. After the dyeing the goods are well rinsed in the

water and then passed into a vat which contains 1 lb. peroxide of sodium

and 1 lb. sulphuric acid. This is started cold, after about fifteen

minutes heat slowly to about 150°, work for twenty minutes, then lift,

wash and dry. For subsequent lots of cotton there only need be used 7

lb. Immedial blue C. 2 lb. sulphide of sodium, 3 lb. salt and 1-1/2 lb.

caustic soda lye at 70° Tw. The blue may also be developed by steaming

with air in a suitable chest or steaming chamber. By topping with 1/4

lb. New methylene blue N, very bright blue shades can be dyed.

_Dark Navy._--Prepare the dye-bath with 25 lb. Immedial blue C, 24 lb.

sulphide of sodium, 35 lb. common salt and 12 lb. caustic soda lye,

working at the boil for one hour, then rinse and develop in a bath made

from 2-1/2 lb. peroxide of sodium and 2-1/2 lb. sulphuric acid, started

cold, then after twenty minutes heated to 160° F., twenty minutes longer

at that heat will be sufficient. For second and subsequent lots of

cotton there is added to the old bath 15 lb. Immedial blue C, 4 lb.

sulphide of sodium, 5 lb. salt and 2 lb. caustic soda lye of 70° Tw.

_Blue._--A pale but not very bright shade of blue is dyed in a bath of 3

lb. Amidazol black 6 G, 5 lb. soda and 25 lb. salt. After working for

one hour at the boil, lift, rinse and pass into a bath which contains

2-1/2 lb. peroxide of sodium and 2-1/2 lb. sulphuric acid; this is

started cold, then heated to 150° F., and kept at that heat for twenty

minutes, when the cotton is taken out, well washed and dried.

_Deep Blue._--Dye with 20 lb. Amidazol black 6 G, 5 lb. soda and 200 lb.

salt; develop with 2 lb. peroxide of sodium and 2-1/2 lb. sulphuric

acid, working as noted above.

_Dark Drab._--Prepare the dye-bath with 20 lb. Cross-dye drab, 5 lb.

soda crystals and 80 lb. salt, work at the boil for an hour, then lift,

wash well and dry; this can be chromed if desired.

_Brown._--Dye with 20 lb. Amidazol cutch, 5 lb. soda ash and 150 lb.

salt, working at the boil for one hour, then lift, wash thoroughly and

dry. By after treatment in a bath of 3 lb. potassium bichromate and 3

lb. sulphuric acid the colour is made fast to washing. The shade is not

altered.

_Buff._--Dye with 2-1/2 lb. Amidazol cutch, 5 lb. soda and 25 lb. salt,

working at the boil for one hour, then lift, wash and dry.

_Pale Sea Green._--Dye with 4 lb. Amidazol green Y, 5 lb. soda and 25

lb. salt, working at the boil for one hour, then lift, wash well and

dry.

_Dark Green._--Dye with 20 lb. Amidazol green B, 5 lb. soda and 20 lb.

salt; work at the boil for one hour, then lift, wash thoroughly and dry.

_Dark Brown._--Dye with 20 lb. Amidazol cachou, 5 lb. soda and 200 lb.

salt, working for an hour at the boil, then lift, rinse well and pass

into a chrome bath of 4 lb. potassium bichromate and 3 lb. sulphuric

acid at 50° F. for half an hour, then wash well and dry.

_Dark Sage._--Dye with 20 lb. Amidazol drab, 5 lb. soda ash and 150 lb.

salt for an hour at the boil, then lift and chrome with 4 lb. potassium

bichromate and 8 lb. sulphuric acid for thirty minutes at 150° F.,

washing well afterwards.

All the Amidazol dyes are very fast to washing, acids, etc. They can be

treated with sulphate of copper or peroxide of sodium when they produce

good shades. They may even be diazotised and developed with

beta-naphthol and phenylene diamine. The pale tints got by using from 2

to 4 per cent. of dye-stuff are useful ones, as also are the medium

shades with 10 per cent. of dye-stuff.

_Brown._--Prepare the dye-bath with 10 lb. Sulfaniline brown 4 B, 50 lb.

salt, 10 lb. soda and 5 lb sulphide of sodium; work at the boil for one

hour, then lift, wash and treat in a fresh bath with 3 lb. potassium

bichromate and 2 lb. acetic acid at 160° F. for half an hour, then wash

well and dry.

_Olive._--Dye with 10 lb. Katigen olive G, 50 lb. salt, 10 lb. soda and

6 lb. sulphide of sodium; work for one hour at the boil, then lift, wash

and treat in a fresh bath with 2 lb. bichromate of potash, 2 lb.

sulphate of copper and 2 lb. acetic acid for half an hour at the boil,

then wash.

_Dark Olive._--Dye with 20 lb. Katigen olive G, 50 lb. salt, 10 lb.

soda, and 6 lb. sulphide of sodium, working at the boil for one hour,

then lift, wash and dry. By chroming a darker and faster olive is got.

_Brown._--Dye with 20 lb. Katigen dark brown, 50 lb. salt, 10 lb. soda

and 6 lb. sulphide of sodium at the boil for one hour, then treat in a

fresh bath with 2 lb. bichromate of potash, 2 lb. sulphate of copper and

2 lb. acetic acid for half an hour at the boil, then wash well.

_Pale Brown._--Dye with 8 lb. Immedial bronze A, 2 lb. soda, 2 lb.

sulphide of sodium and 10 lb. Glauber's salt at the boil for one hour,

then lift, rinse and pass into a fresh bath containing 1 lb. bichromate

of potash and 2 lb. acetic-acid at 150° F. for half an hour, then lift,

wash and dry.

_Dark Brown._--Dye with 12 lb. Immedial brown B, 5 lb. sulphide of

sodium, 5 lb. soda and 20 lb. salt at the boil for one hour, then lift

and treat in a fresh bath with 2 lb. bichromate of potash, 2 lb.

sulphate of copper and 2 lb. acetic acid.

The Immedial blacks, blue, bronze and brown dye very fast shades,

standing soaping, acids and light. They may be combined together to

produce a great range of shades of blue, brown, green, grey, etc.

These examples will perhaps suffice to show how this new but important

class of sulphyl colours are applied to the dyeing of cotton. They may

be topped with aniline black, indigo, basic dyes, or combined with such

direct dyes as produce shades fast to chroming to form a very great

range of shades which have the merit of fastness.

(3) DIRECT DYEING FOLLOWED BY FIXATION WITH DEVELOPERS.

A large number of the dyes prepared from coal tar are called azo

colours, such for instance are the Biebrich and Croceine scarlets and

oranges, Naphthol black, Congo red, etc., just to name a few. The

preparation of these is about the simplest operation of colour

chemistry, and consists in taking as the base an amido compound as the

chemist calls such. These amido compounds, of which aniline, toluidine,

benzidine, naphthylamine are familiar examples, are characterised by

containing the molecular group NH{2}, which radicle is built up of the

two elements nitrogen and hydrogen. All compounds which contain this

group are basic in character and combine with acids to form well-defined

salts. When these amido bodies are treated with sodium nitrite and

hydrochloric acid they undergo a chemical change, the feature of which

is that the nitrogen atoms present in the amido compound and in the

nitrite unite together and a new compound is produced which is called a

diazo compound, and the operation is called "diazotisation".

For example when paranitroaniline is subjected to this reaction it

undergoes a change indicated in the chemical equation:--

C{6}H{4}NO{2}NH{2}, + NaNO{2}, + 2HCl = Paranitroaniline, Sodium

nitrite, Hydrochloric acid.

C{6}H{4}NO{2}N: NCl + NaCl + 2H{2}0 = Paranitro benzene Sodium

chloride, Water, diazo chloride.

The above, put into words, means that when paranitroaniline is dissolved

with hydrochloric acid and treated with nitrite of soda it forms

diazonitro benzene chloride, sodium chloride and water. Now the diazo

compounds are rather unstable bodies, but they have a great affinity for

other compounds, such as naphthol, phenylene diamine, phenol, and

combine easily with them when brought into contact with them. The new

compounds thus made form the dye-stuffs of commerce.

The azo dyes contain the characteristic group of two nitrogen atoms

shown in the formula N: N. In dealing with the production of colours

direct on the fibre this subject will be elaborated more fully.

Now many of the direct dyes, Diamine blacks, Diamine cutch, Primuline,

Diazo brown, Zambesi blues, browns, etc., contain amido groups, by

reason of having been made from such bodies as phenylene diamine, amido

naphthol, toluidine, etc., and it has been found that when dyed on the

fibre they are capable of being diazotised by passing the dyed fibre

into a bath of sodium nitrite acidified with hydrochloric acid, and if

then they are placed into a bath containing such a body as

beta-naphthol, phenylene diamine, etc., new compounds or dyes are

produced, which are characterised by being insoluble in water, and

therefore as formed on the fibre in the manner indicated are very fast

to washing, soaping and similar agencies.

Often the new or developed dye formed on the fibre differs markedly in

colour from the original dye. Perhaps in no case is this more strongly

shown than with Primuline. The original colour is a greenish yellow, but

by using various developers, as they are called, a great variety of

shade can be got, as shown in this table.

_Developer._ _Colour produced._

Beta-naphthol Bright scarlet.

Alpha-naphthol Crimson.

Phenylene diamine Brown.

Phenol Gold yellow.

Resorcine Orange.

Naphthylamine ether Blue.

Blue developer A N Green.

As regards the dyeing operation, it no way differs from that described

for simple direct colours. It should, however, be noted that if good

results are required full shades must be dyed. The cotton must be

rinsed in cold water, and be quite cold before it is subjected to the

diazotising operation. _Diazotising_ is a simple operation, yet it must

be carried out with care if good results are desired. It consists

essentially in the use of an acidulated bath of sodium nitrite.

To make the bath for diazotising there is taken (for each 100 lb. of

goods) sufficient water to handle them in comfortably, 8 lb. of sodium

nitrite and 6 lb. hydrochloric acid. This bath must be quite cold

otherwise it does not work well. The goods are handled in this for from

fifteen to twenty minutes, when they are ready for the next operation.

The bath is not exhausted of nitrite, etc., hence it can be kept

standing, and for each succeeding lot of cotton it is strengthened up by

adding one-third of the quantities of nitrite and acid originally used.

Of course the bath cannot be kept for ever, sooner or later it will get

dirty, and then it must be thrown away and a new bath be made up.

The diazo compounds formed on the fibre are not very stable bodies. They

decompose on being exposed for any great length of time to the air,

while light has a strong action on most, if not all of them; hence it

follows that the diazotising process should not be carried out in a room

where direct, strong sunlight can enter or fall upon the goods. Then

again, after diazotising, the treated goods should not be allowed to lie

about exposed to air and light, but the operation of developing should

be proceeded with at once, otherwise the diazo body will decompose, and

weak and defective colours are liable to be obtained on subsequent

development.

For _developing_, quite a large number of substances are used. Some of

these are regular articles of commerce, others are the special

productions of certain firms, who advise their use with the dyes that

they also manufacture. These latter are sent out under such designations

as Developer B, Developer A N, or Fast-blue developer. Those most in use

are beta-naphthol for red from Primuline, and for bluish blacks from

Diamine blacks, Diazo blacks, Zambesi blacks, etc.; for dark blues from

Diamine blues, Diazo blues, etc.; for greys from Diamine blues, Neutral

grey, etc. Alpha-naphthol for dark reds from Primuline, greys from

Diamine blues, Neutral grey, etc. Phenylene diamine for blacks from

Diamine blacks, Diazo blacks, Zambesi blacks, Triamine blacks, etc.; for

dark browns from Diamine browns, Diazo browns, etc.; for light browns

from Cotton browns, Diamine cutch, Primuline, etc. Naphthylamine ether

for blues from Diamine blacks, etc. Phenol for claret from Diamine

cutch, and for gold yellow from Primuline, etc. Resorcine for orange

from Primuline, etc. Soda for browns from Diamine cutch, Diazo browns,

Zambesi browns, for orange from Diamine orange, and yellow from

Primuline.

=Beta-naphthol.=--This is by far the most important of the developers.

It is a white body, insoluble in water, but readily soluble in soda lye,

and a solution is easily made by taking 10 lb. beta-naphthol and heating

it with 10 lb. caustic soda lye of 70° Tw. and 60 gallons of water. This

bath may be used as the developing bath, or it may be diluted with more

water. It is not desirable to use any more caustic soda than is

necessary to dissolve the beta-naphthol, so that the bath is not too

alkaline. To produce full shades it usually takes 1 per cent. of the

weight of the cotton of the beta-naphthol, but it is best to use the

bath as a continuous one and for the first lot of cotton use 2 per cent.

of naphthol, while for each succeeding lot only 1 per cent. more

naphthol need be added to the same bath.

This bath is alkaline, while the diazotising bath is acid, unless,

therefore, the cotton be well washed when it is taken from the latter

bath there is a risk of the alkali of the one being neutralised by the

acidity of the other, and the naphthol being thrown out in an insoluble

form. This, of course, is easily remedied should it occur.

Developer A (Bayer) is a mixture of beta-naphthol and caustic soda in

the powder form, so that a solution is obtained by simply adding water.

Rather more (about 1-1/2 per cent.) of this is required than of

beta-naphthol.

=Alpha-naphthol= has similar properties to, and is used in the same way

as, beta-naphthol; it develops much darker and rather duller colours,

which are less fast to washing.

=Resorcine=, like naphthol, is insoluble in water, but it can be

dissolved by using either soda ash or caustic soda. The latter is

preferable, as the former is liable to give a developing bath that

froths in working, especially if much acid has been left in the cotton

from the diazotising bath. The proportions are: 10 lb. resorcine, 25 lb.

caustic soda lye of 70° Tw., and 60 gallons of water; or 10 lb.

resorcine, 20 lb. soda ash, and 60 gallons of water, heated until a

solution is obtained. In the developing bath 1 per cent. of resorcine is

usually sufficient to use. It develops an orange with Primuline.

Developer F (Bayer) is a mixture of resorcine and soda ash. It requires

1-1/2 per cent, to make a developing bath.

=Phenol=, better known as carbolic acid, finds a use as a developer. It

is dissolved in caustic soda, 10 lb. phenol, 15 lb. caustic soda lye of

70° Tw., and 60 gallons of water. Generally 1 per cent. is sufficient to

use as a developer. It is often called yellow developer.

=Naphthylamine ether= is used as a developer for blues in conjunction

with the Diamine blacks. It is prepared for use by dissolving in

hydrochloric acid, 10 lb. naphthylamine ether powder heated with 5 lb.

hydrochloric acid and 50 gallons water. About 1-1/4 per cent. is

required to form a developing bath. Naphthylamine ether is also sent out

in the form of a paste mixed with acid, and containing about 25 per

cent. of the actual developer.

=Fast blue developer A D= (Cassella), is amidodiphenylamine. It is

insoluble in water, but soluble in dilute acid, 10 lb. fast blue

developer A D, 5 lb. hydrochloric acid and 35 gallons of water making

the bath. To develop full shades 1 to 1-1/2 per cent, is required.

=Blue developer A N= (Cassella). The base of this is insoluble in water,

but dissolves in soda, and is probably a naphthol-sulpho acid. The

product, as met with in the market, is soluble in water, and 27 lb.

dissolved in 20 gallons of water form the bath. To produce full shades

1-1/2 per cent, is usually required.

=Phenylene diamine= is a most important developer. It comes into the

market in two forms, as a powder, very nearly pure, made into a solution

by dissolving 10 lb. with 20 gallons of water and 5 lb. hydrochloric

acid, and as a solution prepared ready for use. Developer C (Bayer) and

developer E (Bayer) are preparations of diamine, the former in a powder,

the latter in a solution. Phenylene diamine can be used with the

addition to the developing bath of acetic acid or soda.

=Schaeffer's acid= is a sulpho acid of beta-naphthol, and is dissolved

by taking 10 lb. of the acid and 7-1/2 lb. soda, boiling with 50 gallons

of water. About 1-1/4 per cent. is required for developing full shades.

Developer B (Bayer) is ethyl beta-naphthylamine, in the form of its

hydrochloric acid compound. The bath is made from 10 lb. of the

developer and 50 gallons of water, 1-1/4 per cent. being used to obtain

full shades.

Developer D (Bayer) is dioxy-naphthalene-sulpho acid, and simply

requires dissolving in water to make the bath.

=Toluylene diamine= is a homologue of phenylene diamine and is used in

precisely the same way.

Generally the special developers issued by the various colour firms

simply require dissolving in water to form the developing bath.

The cotton, previously being passed through the diazotising bath, is

then run into the developing bath, in which it is kept for from twenty

to thirty minutes or until the required shade is fully developed, after

which it is taken out, rinsed and dried. The method of working is the

same for all the developers, and may be carried out in any kind of

vessels. As is indicated above, the developing baths may be kept

standing and be freshened up as required; they are used cold. Sometimes

two developers are mixed together, in which case care should be taken

that an alkaline developer naphthol or phenol be not mixed with an acid

developer (phenylene diamine, naphthylamine, etc.), unless the acidity

of the latter has been neutralised with soda; otherwise the developer

might be thrown out of the bath in an insoluble and hence useless form.

The advantages of the diazotising and developing process just described

may be summed as--easy and quick working, superior fastness to washing,

soaping and milling, increased fastness to light and softness of the

dyed fibre.

_Scarlet._--Dye with 3 lb. Primuline and 20 lb. salt, at the boil for

one hour, diazotise and develop with beta-naphthol.

_Crimson._--Dye with 3 lb. Primuline and 20 lb. salt, then diazotise and

develop with alpha-naphthol.

_Red Brown._--Dye with 4 lb. Primuline and 20 lb. salt, then diazotise

and develop with phenylene diamine.

_Deep Orange._--Dye with 3 lb. Primuline and 20 lb. salt, then diazotise

and develop with resorcine.

_Pale Orange._--Dye with 3 lb. Primuline and 20 lb. salt, then diazotise

and develop with phenol.

_Sage Brown._--Dye with 6 lb. Primuline, 3 lb. Titan ingrain blue and 20

lb. salt, then diazotise and develop with resorcine.

_Dark Maroon._--Dye with 6 lb. Primuline, 3 lb. Titan ingrain blue and

20 lb. salt, then diazotise and develop with beta-naphthol.

_Dark Crimson._--Dye with 5-3/4 lb. Primuline, 1/4 lb. Titan ingrain

blue and 20 lb. salt, then diazotise and develop with beta-naphthol.

_Dark Blue._--Dye with 3 lb. Zambesi blue B X, 2 lb. soda and 20 lb.

Glauber's salt, then diazotise and develop with amidonaphthol ether.

_Dark Brown._--Dye with 8 lb. Zambesi brown 2 G, 2 lb. soda and 20 lb.

Glauber's salt, then diazotise and develop with toluylene diamine.

_Blue Black._--Dye with 4 lb. Zambesi blue B X, 2 lb. Zambesi black D, 2

lb. soda and 20 lb. salt, then diazotise and develop with 3/4 lb.

toluylene diamine and 1/2 lb. beta-naphthol.

_Red._--Dye with 4-1/2 lb. Primuline, 1/2 lb. Diamine fast yellow A and

20 lb. salt, then diazotise and develop with beta-naphthol.

_Dark Brown._--Dye with 4 lb. Primuline, 1 lb. Diamine azo blue R R, and

20 lb. salt, then diazotise and develop with beta-napthol.

_Deep Chestnut Brown._--Dye with 5 lb. Diamine cutch, 1 lb. soda and 20

lb. Glauber's salt, then diazotise and develop by passing for twenty

minutes in a boiling bath of soda.

_Dark Brown._--Dye with 4 lb. Diamine cutch, 1 lb. Diamine black B H, 2

lb. soda and 20 lb. Glauber's salt, then diazotise and develop with

phenol.

_Black Brown._--Dye with 1 lb. Diamine brown M, 1-1/2 lb. Primuline, 1

oz. Diamine black B H, 2 lb. soda and 20 lb. Glauber's salt, then

diazotise and develop with phenylene diamine.

_Blue._--Dye with 2 lb. Diaminogene blue B B, 1/2 lb. soda and 20 lb.

Glauber's salt, then diazotise and develop with beta-naphthol. A dark

blue is got by using 8 lb. of Diaminogene blue B B in the same way.

_Dark Blue._--Prepare the dye-bath with 1-1/2 lb. Diaminogene blue B B,

1-1/10 lb. Diamine azo blue R R, 2 lb. soda and 20 lb. Glauber's salt.

Dye at the boil for one hour, rinse slightly in cold water, then enter

into a fresh cold bath prepared with 4 lb nitrite of soda previously

dissolved in water, and 12-1/2 lb. hydrochloric acid. For subsequent

lots in the same bath one-third of these additions is sufficient. After

diazotising rinse the goods in a bath weakly acidulated with

hydrochloric or sulphuric acid, and then immediately develop with

beta-naphthol.

_Black._--Prepare the dye-bath with 3 lb. Triamine black B, 15 lb.

Glauber's salt, in fifty gallons of water. Dye exactly as in the

preceding recipe. Wash and rinse very thoroughly after lifting, then

diazotise in a bath of about 250 gallons of cold water, to which add

separately 2-1/2 lb. sodium nitrite dissolved in five times its bulk of

water and 8 lb. hydrochloric acid diluted. Enter the damp cotton and

treat it for about half an hour. Lift, pass through a weak acid bath,

rinse, and develop immediately in a bath of about 250 gallons of cold

water, containing 1 lb. developer T, 1 lb. soda, previously dissolved

together in hot water. Enter the damp goods, work well for half an hour,

then lift, wash and dry.

_Blue Black._--Dye with 4 lb. Diamine black B H, 2 lb. soda and 10 lb.

Glauber's salt, then diazotise and develop with naphthylamine ether.

_Dark Navy._--Dye with 3 lb. Diamine azo blue R R, 2 lb. soda and 10 lb.

Glauber's salt, then diazotise and develop with beta-naphthol.

_Light Chestnut Brown._--Dye with 2 lb. Cotton brown N, 1 lb. diamine

fast yellow A, 1 lb. soda and 10 lb. salt, then diazotise and develop

with phenylene diamine.

_Dark Brown._--Dye with 5 lb. Diamine cutch, 3 lb. soda and 20 lb.

Glauber's salt, then diazotise and develop with fast blue developer A D.

_Black._--Dye with 4 lb. Diamine black B H, 3 lb. soda and 20 lb.

Glauber's salt, diazotise and develop with 2 lb. resorcine and 1 lb.

phenylene diamine.

_Blue Black._--Dye with 4 lb. Diaminogene B, 2 lb. soda and 20 lb.

Glauber's salt, then diazotise and develop with beta-naphthol.

_Black._--Dye with 4-1/2 lb. Diaminogene B, 1/2 oz. Diamine fast yellow

B, 3 lb. soda and 20 lb. Glauber's salt, then diazotise and develop with

3 lb. resorcine and 1 lb. phenylene diamine.

_Light Blue._--Dye with 1-1/2 lb. Diaminogene blue B B, 1 lb. soda and

10 lb. Glauber's salt, then diazotised and develop with beta-naphthol.

_Maroon._--Dye with 6 lb. Primuline and 20 lb. salt, diazotise and

develop with blue developer A N.

_Olive Brown._--Dye with 5-1/2 lb. Diamine cutch, 3 lb. soda and 10 lb.

Glauber's salt, then diazotise and develop with fast blue developer A D.

_Gold Brown._--Dye with 1 lb. Cotton brown N, 3/4 lb. Diamine bronze G,

2 lb. soda and 10 lb. Glauber's salt, then diazotise and develop with

phenylene diamine.

_Walnut Brown._--Dye with 3 lb. Diamine brown M, 3 lb. soda and 20 lb.

Glauber's salt, then diazotise and develop with beta-naphthol.

_Brown._--Dye with 1-1/2 lb. Diamine brown M, 1 lb. Diamine fast yellow

B, 1 lb. cotton brown N, 1 lb. soda and 10 lb. Glauber's salt, then

diazotise and develop with phenylene diamine.

_Dark Plum._--Dye with 3 lb. Diamine brown V, 1 lb. soda and 10 lb.

Glauber's salt, then diazotise and develop with beta-naphthol.

_Black Brown._--Dye with 3 lb. Diamine cutch, 3 lb. Diamine black B H, 8

lb. soda and 20 lb. Glauber's salt, then diazotised and develop with

phenylene diamine.

_Blue Black._--Dye with 4-1/2 lb. Diamine black R O, 3 lb. soda and 20

lb. Glauber's salt, then diazotise and develop with beta-naphthol.

_Blue Black._--Dye with 4-1/2 lb. Diamine black R O, 3 lb. soda and 20

lb. Glauber's salt, then diazotise and develop with naphthylamine ether.

_Blue Black._--Dye with 5 lb. Diamine black B O, 3 lb. soda and 20 lb.

Glauber's salt, then diazotise and develop with beta-naphthol.

_Dark Blue._--Dye with 4 lb. Diamine black R O, 3 lb. soda and 20 lb.

Glauber's salt, then diazotise and develop with blue developer A N.

_Black._--Dye with 5 lb. Diamine black R O, 1 oz. Diamine bronze G, 3

lb. soda and 20 lb. Glauber's salt, then diazotise and develop with

phenylene diamine.

The Diamine blacks are a range of very useful dye-stuffs, and by their

means alone and in conjunction with the various developers as seen in

the examples given above a range of useful shades of blue, navy blue,

and blacks of every tone can be obtained. It may also be added that many

of the direct dyes, although not diazotisable, are not altered by the

process and so may be used along with diazotisable dyes for the purpose

of shading them, and in that way a great range of shades can be

produced, particularly by combining Primuline with other dyes.

(4) DIRECT DYEING FOLLOWED BY FIXATION WITH COUPLERS.

A further development in the application of the direct dyes has of late

years been made. This is a two-bath method. The cotton is dyed with

certain of the direct dyes: Primuline, Diamine jet blacks, Diazo blacks,

Toluylene orange and brown, Diazo brown, Diamine nitrazol dyes, Benzo

nitrol dyes, etc., in the usual way. Then a bath is prepared by

diazotising paranitroaniline, benzidine, metanitraniline, dianisidine,

etc., or by using the ready diazotised preparations which are now on the

market, Nitrazol C, Azophor red P N, Azophor blue P N, etc., and

immersing the dyed cotton in this bath. Combination takes place between

the dye on the fibre and the diazo compound in this bath, and a new

product is produced direct on the fibre, which being insoluble is very

resistant to washing and soaping. These "coupled" shades, as they will

probably come to be called, differ from those produced on the fibre by

the original dye-stuff, thus the Diamine jet blacks and some of the

Diazo blacks give, with paranitroaniline, browns of various shades.

In this section also may be considered the method of dyeing cotton by

using the direct colours in the ordinary way, and then "topping," as it

is called, with a basic dye in a fresh bath.

Practically in the "coupling process" of dyeing only diazotised

paranitroaniline is used as the coupler, although other amido bases of a

similar nature are available.

When paranitroaniline is used as the source for the coupling bath it is

well to prepare a stock bath of diazotised paranitroaniline, which may

be done in the following manner:--

=Preparation of diazotised paranitroaniline.=--Take 1 lb.

paranitroaniline, mix with 1 gallon boiling water and 1 quart

hydrochloric acid, stir well, when the paranitroaniline will dissolve

the solution may if necessary be assisted by a little heat. Now add

1-1/2 gallons of cold water, and set aside to cool, when the

hydrochloride of paranitroaniline will separate out in the form of fine

crystals; when the mixture is quite cold (it cannot be too cold) there

is added 1/2 lb. sodium nitrite dissolved in 1/2 gallon cold water, stir

well for fifteen to twenty minutes, by the end of which time the

paranitroaniline will have become fully diazotised, cold water is added

to bring up the volume of the mixture to 10 gallons. This stock bath

well prepared and kept in a cool, dark place will keep good for three to

four weeks. This bath contains 1 lb. of paranitroaniline in 10 gallons,

and it is a good rule to allow 1/2 lb., or 5 gallons of this stock bath

to each pound of dye-stuff used in dyeing the ground colour to be

developed up.

To prepare the coupling bath there is taken 5 gallons of the stock bath,

1 lb. sodium acetate with sufficient water for each 1 lb. of dye that

has been used.

This bath is used cold, and the cotton is worked in it for half an hour,

then it is taken out, washed well and dried.

Nitrazol C is a ready prepared diazotised paranitroaniline in a powder

form which keeps well if stored in a dry place. The method of using is

to take 8 lb. Nitrazol C, stir into a paste with water and then add this

paste to the coupling bath, together with 2 lb. soda and 3/4 lb. acetate

of soda. This bath is used cold and the dyed cotton is immersed in it

for half an hour, then taken out, well washed and dried.

The quantity of Nitrazol C given will suffice for all shades dyed with

from 2 to 4 per cent, of dye-stuff, but when paler shades are dyed,

using less than say 1/2 per cent. of dye-stuff, about 4 lb. Nitrazol C,

with the soda and acetate of soda in proportionate quantities, may be

used.

Azophor red P N is also a preparation of diazotised paranitroaniline in

the form of a dry powder which keeps well.

To prepare the coupling bath there is taken 2 lb. of Azophor red P N,

which is dissolved in water and added to the bath along with 1 lb.

acetate of soda. The dyed goods are worked in the cold bath for half an

hour, then taken out, well washed and dried.

The quantities given are sufficient for shades dyed with 2 to 4 per

cent. of dye-stuff; for weaker shades half the quantities may be taken.

Benzo-nitrol developer is sold in the form of a yellow paste. To use it

take 5 lb., stir into a smooth paste with water, then add to the

coupling bath. There is then added 3 pints of hydrochloric acid, with

some stirring. Allow to stand for half an hour, add 1-1/2 lb. acetate of

soda and 6-1/2 oz. soda, when the bath is ready for use. The cotton is

entered and worked for half an hour, then lifted out, washed and dried.

It may be mentioned that solutions of the three couplers just named may

be kept for some time without decomposition, but as soon as soda and

acetate of soda are added they begin to decompose and then cannot be

kept more than a few hours in a good condition. It is a good plan

therefore not to add the acetate of soda until the bath is to be used.

An excess of coupler in the bath does no harm, but a deficiency may lead

to poor and weak shades being developed.

The following recipes show the dyes which may be applied by this method

and give some idea of the colours that can be got. Only the dye-stuffs

are given. Any of the above couplers can be used with them as may be

most convenient.

_Black._--Dye with 5 lb. Benzo-nitrol black B, 1 lb. soda and 20 lb.

Glauber's salt.

_Olive Green._--Dye with 6 lb. Primuline, 3 lb. Titan ingrain blue and

20 lb. salt.

_Black._--Dye with 4 lb. Dianil black C R, 2 lb. soda and 25 lb. salt.

_Dark Blue._--Dye with 2 lb. Dianil dark blue R, 1 lb. Dianil dark blue

3 R, 2 lb. soda and 25 lb. salt.

_Gold Brown._--Dye with 1 lb. Primuline, 8 oz. Dianil brown R and 20 lb.

salt.