BLEACHING
The other section of preparatory work for plait is that of Bleaching.
The early efforts in this direction were of necessity very crude,
and it is probable that imitation of the process used in some other
industry, rather than invention for the particular commodity, provided
the primary steps in straw bleaching. Naturally, the first thing that
would occur to anyone would be to wash with water, and any grower of
cereals, knowing the bleaching power of the sun, would probably combine
these two elements in the endeavour to produce a better colour on the
corn stalks. Then some attempts would be made with a cleanser such as
soap, still utilizing the sun’s rays as bleacher after cleaning. As
Italy is probably the home of bleaching operations, it is not difficult
to imagine that, with the sulphur bleaching effects so easily seen
round the Bay of Naples and in Sicily, it was not long before the fumes
of sulphur were pressed into the service. And crude as these elements
are, although the processes have radically changed, they remain
practically the fundamentals of bleaching to-day.
About seventy years ago, Mr. Welch, of the firm of Welch & Sons, of
Luton (one of the oldest established houses in the trade and still in
existence), patented a bleach which was called the “Luton Bleach.” This
consisted of carefully washing the plait with soap and water in wooden
vats; after careful rinsing it was immersed in a bath of weak oxalic
acid and water (some bleachers subsequently added other chemicals),
and then while wet subjected to the fumes of sulphur in a hermetically
closed wooden chest. Hanging out in the sunshine to dry, and another
sulphur fumigation before “bunching” (as the tying up of plait into
bundles is termed), completed the operation. With chip plaits, and
fifty or more years ago these were very fashionable, a similar process
was usual, but the bleaching bath contained, as well as oxalic acid,
kali, tartar, and a good many other similar ingredients, according to
the requirements of the user. In those days nearly all bleaching was
done by the actual manufacturer of the hats, it was only when the trade
began to move by leaps and bounds that works entirely for bleaching
purposes were established. For many years these methods of bleaching
were the only ones employed on plaits for hats, and they produced
excellent results on really good coloured straws; but failed entirely
to eliminate any faulty parts, and further, in order to get the finest
colour, two more sulphur fumigations were necessary; one when the hat
was wet from the gelatine employed to stiffen it, and the other a dry
“steam” (as the fumigation was called) before putting the finished hats
into the cases for dispatch.
This custom of bleaching, in a patriarchal way in one’s own tent,
brought out considerable inventiveness on the part of go-ahead
manufacturers, and it was no uncommon thing for some fresh development
of bleaching, on one or another plait, to establish the reputation
of a manufacturer, who, until his secret leaked out, endeavoured to
exploit to the full the value of his superior article. But this kind
of bleaching only cleaned and purified, it did not materially alter
the natural condition of the article bleached. In the first place
manufacturers were not laboratory chemists, and it was the efforts of
the Italians, the producers of the plait which was supplanting the
British product, that gave birth to a chemical bleach, which for some
time was unrivalled in England. For some years the bleached Italian
Pedal of Messrs. Burgisser & Co., of Florence, had no superior, and
was for a long period renowned for the purity and beauty of its
colour process. But the secret subsequently leaked out, and bleaching
establishments in this country soon acquired them, and it was not long
before the results obtained here compared favourably with the Italian.
For some years this bleach, which not only cleansed and purified the
straw, but also changed its actual tone by bringing more into colour
line the straws of darker hue, was accepted by the world as the best
possible; and one may say that, although later developments have
considerably widened the scope of operations, the results of this
period, which may be called the intermediate cycle of straw bleaching,
were in their way quite equal to any now achieved. The only drawback
to this bleach was that really inferior coloured plait could not be
made serviceable for white. In the case of chip splints or in the case
of cornstalks, only the best and clearest of either of these had been
used for plaits for bleaching. This necessitated keeping two stocks
of plait, for although the best coloured plait could be dyed black
or other shade if necessary, the bad coloured straws could not be
bleached, and further, one always had to pay more for the best coloured
goods, which although to some extent this is even now the case,
owing to the great possibilities opened up by the present bleaching
processes, there is not the wide difference in price there used to be.
But at last competitive chemists discovered that the quantity of straw
plait required for bleaching was of such magnitude, while the really
good bleaching plait was comparatively so small in quantity, that
it would be worth their while to make researches in the direction
of a bleach for inferior coloured straws. Between 1885 and 1890 many
experiments were made, with naturally variable results. It must not
be overlooked, that plaits were still required by the trade to be of
a “straw” colour, and the first efforts of the “new bleacher” were
towards this end. But the process that gave most promise being actually
an oxydization was more in the nature of a dye than a bleach in one
respect, viz., that it apparently changed the nature of the material,
in fact some of the bleachers to differentiate in the trade between the
new process and the old called the later arrival a “White Dye.” It was
soon found that an extended application of the process would entirely
eliminate the varying tones of mixed “Punta” and “Pedale” straws and
would make the plait a perfectly dull white like paper, but at the same
time it tended to materially injure the fabric of the straw. There
was naturally no demand for any such results, the “paper white” could
easily be obtained on “chip” plaits, and the only effect required was
to reduce mottled coloured natural plaits to sufficient uniformity of
good straw white colour. Moreover, the absolute “deadness” of the white
produced took away all the beautiful lustre of the straw which it was
desirable to retain; and the weakening of the fibre by the chemical
process was entirely inimical to the subsequent proper sewing and
finishing of the hat.
However, a process was found that met all requirements as far as lustre
and strength were concerned. There was still a tendency to kill the
straw colour, but subsequent investigations have reduced that to a
minimum, and to-day the bleaches on straw plaits leave nothing to be
desired.
As far as chip and Tagal plaits were concerned there was not the
occasion to preserve the natural colours of the fibre. White chip was
always required “paper white,” and although some of the hemp fibres of
Tagal were of a flaxen colour, most of that exported from Japan was
distinctly on the white side, and, therefore, from the first, this
process of bleaching has been helpful to all plaits made of these two
materials.
Moreover, the modern methods are especially adaptable for hood hats,
inasmuch as the process dispenses with scrubbing by hand. To Panamas,
although previously the colour had been fairly good, the new bleach
has been a great help, and has enabled Panamas of fine colour to be
universal.
These remarks apply also to the other varieties of Panamas of which,
although the method of making may be slightly different, the fibre is
almost identical; but when one comes to the Bowen or Curaçoa hoods,
their substitutive use has only been possible because of the searching
effects of the new process. Before bleaching, these articles are quite
unfit to sell for white, and their natural tint is not one that would
command a fashionable sale. Since being dyed white, the demand for them
has been phenomenal, and for a low priced, coarse-looking hat of a
Panama nature, there is at present nothing to take their place.
The natural colour of Javas, Brazilians and Bankoks is such that they
are saleable as imported, but although many are thus used, the great
majority of them required for white are bleached by the new process,
and with very excellently clear results. Javas, being the darkest
of the trio mentioned above, can have their colour retained to some
extent, giving the finished article almost a perfect straw tint,
but Brazilians and Bankoks assume a whiter tone without any tinge
of yellow. They, therefore, are very similar to Panamas in colour
appearance, but both of them, being made of flat splints, are lighter
in weight.
Yedda, rush, and raffia plaits and hoods are all very amenable to the
bleach, and while the two latter present, when bleached, little, if
any, lustre, the first named assumes a silky appearance which is most
effective.
To sum up, with the modern process, of which there are several
modifications, any kind of fabric used for straw hats can be
successfully bleached into one or the other tones from straw to paper
white, which are regarded as necessary for the highest grade finish.