Improvements in the Production o1 Fast Dan Printing Fibres and Fabrics.
Year: 1888

page_text: Improvements in the Production o1 Fast Dan
Printing Fibres and Fabrics.
I JOHN CLAYTON MEWBURN, of 169 Fleet Street, in the City of London, Fellow of
the Institute of Patent Agents, do hereby declare the nature of this invention and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
For some years past in the dyeing or printing of fibres and fabrics fast black
colours have been obtained by aniline but it has been found impossible to produce a
black identical with another black derived from coal.
The present invention consists in a novel and more energetic mode or process of
oxidizing by means of which a fast black color can be produced by toluidine. The
novel mode can also be applied to aniline and other like derivatives of coal. According
to this mode or process oxidizing and metallic salts are caused to react by double
decomposition in concentrated solutions on toluidine, aniline or other like derivatives
of coal.
•
By an energetic reaction, one can by oxidizing toluidine produce a fast or perma-
nent black; and by using like means of oxidation one can obtain with aniline or
other like derivatives much faster blacks and colors than by the ordinary processes
with dilute baths which have not the necessary strength to effect a complete oxidation
and the blacks formed have not resistance to friction and air, while the blacks formed
by the new mode of oxidizing are very fast when exposed to air and are not affected
by friction.
The reaction is obtained as follows but it is evident that the process, the oxidizing
and mineral matters, the degrees of temperature and the concentration and strength of
the baths can be varied. The invention consists essentially in the production of fast
or permanent black color by toluidine, aniline or other like coal derivatives by a
reaction of oxidizing and metallic salts in concentrated baths.

page_text: The fabrics or fibres are placed in a bath composed of equal parts of the solutions A
and B and this is agitated while the dyeing is in progress. The fabrics or fibres are
then squeezed or wrung and dried at the usual temperature. They are then passed
into solution C in the ratio of 1 litre to each kilogramme of material. They are after-
wards washed with coid water. The color may be fixed by heat as with aniline blacks
and by the same processes; and it can also be softened or toned down by the ordinary
means.
By this invention firmer blacks are obtained than from aniline oxidized by the
ordinary processes in dilute baths and they do not change by the reducing action of
air or reducing bodies. A considerable advantage is that they do not discharge or
become soiled by rubbing or friction.
For printing, the fabrics can be submitted to the bichromate solution either before
or after being printed with the solutions A and B which should be thickened with the
materials ordinarily employed (gum arabic, tragacanth, fecula, &c.) in the proportion
of from 100 to 200 grammes per litre according to the kind of printing.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, as communicated to me,
I declare that what I claim is :-
The production of fast or permanent black color in dyeing or printing fibres and
fabrics by the oxidation of toluidine, aniline or other derivatives of coal by means of
salts in concentrated baths substantially as set forth.