FUR DYEING
GENERAL METHODS
Before the furs can be dyed, they have to undergo certain preparatory
processes: first, killing, which renders the hair more susceptible to the
absorption of the dye; and second, mordanting, which consists in treating
the killed fur with chemicals which help the dye to be fixed on the hair.
Then the skins are ready to be dyed.
There are two principal methods by which dyes are applied to furs in
practise: the brush process, whereby only the tips or the upper part
of the hair are colored; and the dip process, whereby the entire fur,
including the leather is dyed. All other procedures in fur dyeing
are modifications or combinations of these two. Killing solutions and
mordanting solutions are also applied by one of these methods, usually
the dip process, although very frequently combinations of the brush and
dip methods are used.
Chronologically the brush method of dyeing came first. The early masters
of the art were extremely fearful about employing any means by which
there was a possibility of the leather being in any way affected. They
naturally had to devise such methods as would give the desired effect
in a satisfactory manner, and as would be confined solely to the hair
part of the fur, leaving the leather untouched. By applying the dye
or other material to be used, in the form of a paste with a brush, the
upper portion of the hair only was treated. For different kinds of furs
different sorts of brushes were used, and the depth to which the hair was
colored could be controlled by skillful manipulation of the brushes. It
was frequently necessary to give a ground color to the hair, the lower
part being dyed a different shade from the tips. This was accomplished
by spreading the dye paste over the hair with a broad brush, and then
beating the color in with a specially adapted beating brush. With larger
furs, two skins were placed hair to hair after the dye had been brushed
on, and the color forced to the bottom of the hair by a workman tramping
on the skins. The dyeing of seal was a typical illustration of these
procedures. First the tips of the hair were dyed. The color was brushed
on, allowed to dry, then the excess beaten out with rods. These operations
were repeated until the proper depth of shade was obtained, often as many
as a dozen or more applications of the dye being necessary. Then the base
color was spread over the hair, and beaten or tramped in until the lower
parts of the hair were penetrated. This process also required drying and
beating out of the excess dye, as well as numerous applications of the
dye to impart the desired color to the hair. Prior to the dyeing, the furs
were killed, by brushing on a paste containing the essential ingredients,
drying and beating and brushing the fur, just the same as in dyeing. It
will be readily seen that such methods were exceedingly laborious, and in
some cases the dyeing took many weeks, and even months.
It was quite a step forward when a certain fur dyer, possessing a little
more courage, or perhaps, experimenting spirit than the others, attempted
to dye furs by dipping them entirely into a bath containing a solution
of the dye instead of applying a paste as formerly. The advantages to be
gained by such a method of dyeing were many. A large number of skins could
be treated thus at one time, and this was a very important consideration
in view of the great increase in the demand for dyed furs. By allowing the
furs to remain in the dye solution until the proper shade was obtained,
the time and labor of applying many coats of dye by brush was considerably
reduced, and in addition, there was a greater probability of the products
coming out all alike, uniformly dyed. The results as far as the hair
was concerned, were indeed highly gratifying, but the condition of the
leather after dyeing was not so encouraging. This difficulty has to a
considerable degree been overcome, although there are frequent instances
of the leather being affected by the dyeing process even with modern
methods. However, the remedy in such cases, or rather the preventative
is the proper dressing of the skins prior to the dyeing. The dip method
of dyeing has acquired great importance, and is being employed in dyeing
operations involving the handling of millions of skins annually. In
certain instances, nevertheless, the brush method is of prime significance
as in the dyeing of seal, and seal imitations on muskrat and coney,
enormous quantities of furs being dyed in this fashion. In the majority
of imitations dyed, both the brush and the dip methods must be used.
Figure 19 illustrates the various types of brushes which are used at the
present time for the application of the dye by the brush method. Each
brush has a specific purpose and use. The procedure in brush dyeing is
somewhat as follows. The skins, after being properly treated, that is,
killed, and mordanted, are placed on a table, or work-bench, hair-side up.
Then by means of a brush which is adapted to the nature and requirements
of the particular fur, the solution is brushed on in the direction of
the fall of the hair, occasionally beating gently with the brush so as to
cause the dye to penetrate to the desired depth. Considerable skill and
care must be exercised in this operation as it is rather easy to force
the dye down further than is wanted, and in some cases the leather or the
roots of the hair may be affected. The skin having received its coat of
dye, is then dried and finished, if no other dyeing processes are to be
applied. Frequently, with certain types of dyes, several applications of
color are necessary, and these are brushed on as the first one, drying
each time. Then, on the other hand, the skin may receive a dyeing in the
bath by dipping, and for this also, the fur is first dried after the brush
dyeing.
[Illustration: FIG. 19. BRUSHES USED IN FUR DYEING BY THE BRUSH METHOD.]
Quite recently, owing to the great quantities of furs which are being
dyed as seal imitations, chiefly by the brush method, although the dip
method is used in conjunction with it, machines have been invented to
replace the hand brush, and the dye is now applied mechanically. Machines
for this purpose are by no means new, there being records of inventions
almost a score of years past, but they did not achieve much success.
Brush-dyeing machines, to be efficient, must be designed to suit the
needs of the particular type of fur to be dyed, otherwise there will be
a great lack of uniformity in the dyed skins, a condition which cannot
occur when the dye is brushed on by hand brushes. Figure 20A and B shows
diagrammatically, machines invented within the past few years, which are
used to dye mechanically furs by the brush process.
[Illustration: FIG. 20. TYPES OF MACHINES FOR DYEING FURS BY THE BRUSH
METHOD.
_A._ (U. S. Patent 1,225,447.) _B._ (U. S. Patent 1,343,355.)]
[Illustration: FIG. 21. DRUM FOR WORKING WITH LIQUIDS.
(_Turner Tanning Machinery Co., Peabody, Mass._)]
For the dipping process, the dye solution is prepared in vats, or
liquid-tight drums, or in some instances in paddle arrangements. The
skins are placed in the dye-bath, and the dyeing operation proceeds
without any difficulty. After the proper shade is obtained, the furs
are removed, washed free of excess dye, dried and finished. The dipping
method is employed where a single shade is to be dyed on the fur, as the
production of blacks on lambs. But in most cases, the dyeing in the bath
is supplemented by the application of a coat of dye by the brush to the
upper part of the hair, the color being usually a darker shade than the
ground dyeing. Thus, for example, in the dyeing of imitation sable on
kolinsky or a similar fur, the skins are first dyed the relatively light
color of the under-hair by the dip process, then the dark stripe effect
is brushed on.
The blending of sables, martens, chinchillas or other rare furs, is not
done in the same manner as with other furs, because each skin requires
individual attention and a long and careful treatment. The dye solution
is applied by means of very fine brushes or sometimes feathers, to the
extreme tips of the hair, until the proper degree of color intensity is
obtained. The time, labor, and skill necessary for this sort of work are
warranted only in the case of the highest-priced furs, and the blendings
are so excellent as to defy detection, except by experts.
[Illustration: FIG. 22. DEVICE FOR CONVEYING SKINS.
(_Turner Tanning Machinery Co., Peabody, Mass._)]
After the furs have gone through all the operations required by the
processes of killing, mordanting, dyeing and washing, they are ready to
be dried and finished. The procedure is quite similar to that employed in
fur dressing. Sometimes the leather side of the skins is brushed with a
strong salt solution before drying, in order to replace some of the salt
which was extracted during the dyeing processes. In other instances, a
light coat of some oily substance is brushed on, to render the leather
soft and flexible after drying, where there is a possibility of the skins
turning out otherwise. Great care must be exercised in the handling of
the dyed skins to avoid the formation of stains or spots on the hair,
which might ruin the dyeing. As little handling of the furs as is feasible
will reduce any trouble from this source. In conveying the wet skins
from one part of the plant to another it is desirable to use a device
such as is shown in Fig. 22. For drying, the same machines as described
under Fur Dressing can be used, and similar care must be taken to avoid
overheating or irregularity of drying. Drum-cleaning constitutes a very
important operation in the finishing of the skins, the hair receiving
a polish, and the full lustre and brilliancy of the dye being thereby
brought out. Then after caging to remove the sawdust or sand, the skins
are passed over the staking knife, or are treated in a machine suited
for the purpose, to stretch them and to render them thoroughly soft and
flexible. And therewith is concluded the work of the fur dyer proper, and
the skins are ready to return to the furrier, in whose hands they undergo
the metamorphosis into the fur garments to be worn chiefly by the feminine
portion of humanity.