Improvements in Mordanting Cotton or other Vegetable Fibre,
Year: 1898

page_text: Date of Application, 17th Oct., 1898
411
Complete Specification Left, 14th July, 1899-Accepted, 26th Aug., 1899
PROVISIONAL SPECIFICATION.
Improvements in Mordanting Cotton or other Vegetable Fibre,
I, JAMES YATE JOHNSON, of 47, Lincoln's Inn Fields, in the County of London,
Gentleman, do hereby declare the nature of this invention (which has been com-
municated to me from abroad by the Badische Anilin & Soda Fabrik, of Lud-
wigshafen-on-Rhine, in the German Empire) to be as follows:-
Under the name of chrome bisulphite, a product, prepared by dissolving freshly
precipitated chrome oxide in aqueous sulphurous acid containing some sulphuric
acid, is used as a mordant. The present invention relates to an improved process
for fixing chrome oxide on cotton and other vegetable fibres, making use of the
said product.
Although chrome mordants have been largely used for many years on animal
and vegetable fibre, still all the processes for fixing chrome oxide for use as a
mordant on cotton and other vegetable fibre have suffered from some disadvantage
or other. Some of the processes involved drying the material, after treating with
mordant solution, and were consequently expensive. In some of them it was
difficult to obtain even shades, so that although applicable to piece goods, and
other cases where it was possible to ensure an even application of the mordanting
solution, still they were not applicable to cotton yarn, loose cotton, or the like.
Again, when mordanting by some of the old processes for fixing chrome on the
on the fibre, would not adhere to
fibre, the chrome oxide, although precipitated
it, but was liable to be washed away when swilling the goods.
The present invention affords a cheap method of fixing chrome oxide on cotton,
or other vegetable fibre, in such a way that uniform dyeings can subsequently
or other
be obtained even on cotton or other vegetable yarns and loose cotton
vegetable fibres. It can also be applied to piece goods with advantage.
The main feature of the process consists in impregnating the material to be
mordanted with a comparatively dilute solution of chrome bisulphite, and sub-
sequently treating the goods with a salt that acts as an alkali, (such for instance,
as carbonate, or bicarbonate, of soda, carbonate of potash, phosphate of soda, or
the like,) when the fixing of the chrome on the fibre takes place quite evenly.
The following example will serve to further illustrate the nature of the inven-
tion, but the invention is not confined to this example:-
Take about 100 lbs. of cotton yarn, which have been previously thoroughly
boiled, and wrung out in a centrifugal machine, and steep them, for
a chrome bisulphite solution,
several hours, preferably over night, in
of 10 degrees Beaumé, (15 degrees Twaddell). Wring out the goods
excess of chrome bisulphite solution
thoroughly, and free them from
by treating them in a centrifugal machine. Then, without drying, pass them,
for about ten to fifteen minutes, through a bath containing about 3 grammes of
calcined soda for every litre of water, and which is maintained at a temperature
of 60 degrees Centigrade. Wash the goods, treat them once more in the centri-
solution which contains about
fugal machine, and then steep them in
100 grammes Turkey red oil for every litre of water, and then dry.
a

page_text: The unabsorbed chrome-bisulphite solution can be used repeatedly, only suffi-
cient fresh concentrated solution must be added after each operation to bring it
to the desired strength. Goods mordanted with a chrome bisulphite solution of
the aforesaid strength yield dark shades when dyed. For medium shades the
mordanting bath need only be of-5 degrees Beaumé, (7.2 Twaddell) and for light
shades of 3 degrees Beaumé, (44 Twaddell). The quantity of soda in the fixing
bath can also be diminished in a corresponding manner. The
process, as illus-
trated by the above example, can be applied to loose cotton, and to cotton piece
goods, and also to linen and hemp. Instead of soda, other salts which act as
alkalies can be used.
Dated this 17th day of October 1808.
COMPLETE SPECIFICATION.
Improvements in Mordanting Cotton or other Vegetable Fibre.
..I, JAMES YATE JOHNSON, of 47, Lincoln's Inn Fields, in the County of London,
Gentleman, do hereby declare the nature of this invention (which has been coni-
municated to me from abroad by the Badische Anilin & Soda Fabrik, of Lud-
wigshafen-on-Rhine, in the German Empire) and in what manner the same is
to be performed to be particularly described and ascertained in and by the follow-
ing statement:-
Under the commercial name of chrome bisulphite, a product, prepared by dis-
solving freshly precipitated chrome oxide in aqueous sulphurous acid containing
some sulphuric acid is used as a mordant. The present invention relates to an
improved process for fixing chrome oxide on cotton and other vegetable fibres,
making use of the said product.
Although chrome mordants have been largely used for many years on animal
and vegetable fibre, still all the processes for fixing chrome oxide for use as a
mordant on cotton and other vegetable fibre have suffered from some disadvantage
or other. Some of the processes involved drying the material after treating with
the mordant solution, and were consequently expensive. In some of them it was
difficult to obtain even shades, so that although applicable to piece goods and
in other cases where it is possible to ensure an even application of the mordanting
solution, still they were not applicable to cotton yarn, loose cotton; or the like.
Again, when mordanting by some of the old processes for fixing chrome on the
fibre, the chrome oxide, although precipitated on the fibre, would not adhere to
it, but was liable to be washed away when swilling the goods.
The present invention affords a cheap method of fixing chrome oxide on cotton,
or other vegetable fibre, in such a way that uniform dyeings can subsequently
be obtained even on cotton, or other vegetable yarns, and loose cotton, or other
vegetable fibre. It can also be applied to piece goods with advantage.
The main feature of the process consists in impregnating the material to be
mordanted with a comparatively dilute solution of chrome bisulphite, and sub-
sequently treating the goods, without previously drying them, with a salt that
acts as an alkali, (such, for instance, as carbonate, or bicarbonate, of soda,
carbonate of potash, phosphate of soda, or the like) when the fixing of the chrome
on the fibre takes place quite evenly.
The following example will serve to further illustrate the nature of the inven-
tion and the manner in which it can be performed, but the invention is not
confined to this example:-
-

page_text: Take about 100 kilograms of cotton yarn, which have been previously thoroughly
boiled, and wrung out in a centrifugal machine, and steep the said yarn for
several hours, preferably over night, in a chrome bisulphite solution of 10 degrees
Beaumé, (15 degrees Twaddell). Wring out the goods thoroughly, and free
them from excess of chrome bisulphite solution by treating them in a centri-
fugal machine. Then, without drying, pass them, for about ten to fifteen minutes,
through a bath containing about 3 grammes of calcined soda for every litre of
water, and which is maintained at a temperature of 60 degrees Centigrade. Wash
the goods, treat them once more in the centrifugal machine, and then steep them
in a solution which contains about 100 grammes Turkey red oil for every litre
of water, and then dry.
The unabsorbed chrome-bisulphite solution can be used repeatedly, only suffi-
cient fresh concentrated solution must be added after each operation to bring it
to the desired strength. Goods mordanted with a chrome bisulphite solution of
the aforesaid strength yield dark shades when dyed. For medium shades the
mordanting-bath need only be of 5 degrees Beaumé, (72 Twaddell) and for light
shades of 3 degrees Beaumé (44 Twaddell). The quantity of soda in the fixing
bath can also be diminished in a corresponding manner. The process, as illus-
trated by the above example, can be applied to loose cotton, and to cotton piece
goods, and also to linen and hemp. Instead of soda the other salts hereinbefore
mentioned as acting as alkalies can be used.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is: -
1. Mordanting cotton, or other vegetable fibre, by impregnating the material
to be mordanted with a solution of chrome bisulphite and subsequently treating
the goods, without previously drying them, with a salt that acts as an alkali,
substantially as hereinbefore described.
2. The improved process for mordanting cotton, yarn, substantially as herein-
before-described in the foregoing example.
Dated thin 14th lov of T.1., 1900
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.