Year: 1897

page_text: I, HENRY EDWARD NEWTON, of The Office for Patents, 6 Bream's Buildings,
Chancery Lane, in the County of London, Patent Agent, do hereby declare the nature
of this invention to be as follows:-
The present invention relates to a new process for dyeing unmordanted cotton.
My foreign Correspondents have discovered that Cachou de Laval, Katigen Black-
Brown, Noir Vidal, Verde Italiano, Fast Black, and similar dye-stuffs, which are
obtained by the action of sulphur or alkaline sulphides on different organic sub-
stances, can be dyed very easily and profitably in strong alkaline baths, and that the
above defined colouring-matters, when used in such baths, yield more intense shades
than in a neutral bath, or in a bath containing sodium carbonate, alkaline sulphide,
or the like.
Thus, for instance, black-green shades are obtained in strong alkaline baths by
means of the so called Italian Green, which, dyed in the usual manner, yields only
green shades. Kàtigen black-brown, by means of which only dark brown shades can
be produced according to the method of dyeing hitherto recommended, even if a
from 60 to 100 per cent. dyestuff be employed, dyes cotton deep black shades in strong
alkaline baths containing equal quantities of the dyestuff. In this manner, my foreign
Correspondents have succeeded in obtaining a very cheap and fast black, by means
of the present new process, with Kàtigen Black-Brown.
It will be understood that, by employing strong alkaline baths, the cotton is mer-
cerized at the same time, and if one uses cotton previously stretched, in order to avoid
shrinking, which would be effected by the action of the strong lye, shades which are
dark and fast are obtained in a simple manner by means of one operation, and the
cotton thus dyed exhibits a silky lustre.
In order to illustrate the new process, the following example is given, which is
merely typical.
50 parts by weight of Katigen Black-Brown are dissolved in a small quantity of
hot water, and the resulting solution is added to a cold bath containing 500 litres (in
case the parts are kilos. by weight) of water, and 150 parts of sodium hydroxide.-
50 parts of the well-moistened cotton material in ordinary, or in a stretched state, are
then placed in the bath at ordinary temperature.-The cotton, which is kept from
6 to 10 hours in the bath, is handled from time to time, care being taken that the
fabric remains covered by the liquid. The material is then wrung out, rinsed, and
dried. It exhibits a deep black shade with silky lustre.
My foreign Correspondents do not limit themselves to the particulars given in the
above example; thus, for instance, the concentration of the dyeing bath, and the
quantity of the sodium hydroxide, can vary within certain limits. Of course, other
alkalies, such as potassium hydroxide, can be used in place of sodium hydroxide.

page_text: The dyeing process can be carried out in a manner analogous to that hereinbefore
described, if other dyestuffs, such as Cachou de Laval, Noir Vidal, Verde Italiano
(Italian Green), Fast Black, or the like, are used in place of Kàtigen Black-Brown.
As a matter of course, the process is also applicable when mixtures of the dye-stuffs
herein before defined are employed.
I, HENKY EDWARD NEWTON, of the Office for Patents, 6 Bream's Buildings, Chancery
Lane, in the County of London, Patent Agent, 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 :-
The present invention relates to a new process for dyeing unmordanted cotton.
My foreign Correspondents have discovered that Cachou de Laval, Katigen Black-
Brown, Noir Vidal, Verde Italiano, Fast Black and similar dye-stuffs which are
obtained by the action of sulphur or alkaline sulphides on different organic substances,
if used with strong alkaline baths, will dye unmordanted cotton easily and profitably,
and that the above defined colouring-matters, when used with such baths, yield more
intense shades than when employed with a neutral bath, or with a bath containing
weaker alkaline substances, such as sodium carbonate, alkaline sulphide or the like.
Thus, for instance, black-green shades are obtained with strong alkaline baths,
from the so-called Italian Green, which, when dyed in the usual manner, yields only
green shades.
Katigen-Black-Brown, which gives only dark brown shades when the method of
dyeing hitherto recommended is employed, even if from 60 to 100 per cent. dye-
stuff be used, dyes cotton deep black shades when used with the strong alkaline baths
(containing equal quantities of the dye-stuff), in an economical and satisfactory
manner.
It will be understood that by employing strong alkaline baths, the cotton is
mercerized at the same time, and if one uses cotton previously stretched, in order to
avoid shrinking, which would be effected by the action of the strong lye, dark and
fast shades are obtained in a simple manner by means of one operation, and the
cotton thus dyed exhibits a silky lustre.
In order to illustrate the new process, the following example is given, which is
merely typical.
50 parts by weight of Katigen-Black-Brown are dissolved in a small quantity of
hot water, and the resulting solution is added to a cold bath containing 500 litres
(in case the parts are kilos. by weight) of water, and 150 parts of sodium hydroxide
50 parts of the well moistened cotton material, in ordinary or in a stretched state,
are then placed in the bath at ordinary temperature. The cotton which is kept
from 6 to 10 hours in the bath, is handled from time to time, care being taken that
the fabric remains covered by the liquid. The material then is wrung out, rinsed,
and dried. It exhibits a deep black shade with silky lustre.
My foreign Correspondents do not limit themselves to the particulars given in the
above example: thus, for instance the concentration of the dyeing-bath, and the
quantity of the sodium hydroxide, can vary within certain limits. Of course, other
alkalies, such as potassium hydroxide, can be used in place of sodium hydroxide.

page_text: The dyeing process can be carried out in a manner analogous to that herein before
described, if other dye stuffs, such as Cachou de Laval, Noir-Vidal, Verde Italiano
(Italian Green), Fast-Black, or the like, are used in place of Katigen-Black-Brown.
As a matter of course, the process is also applicable when mixtures of the dye-stuffs
hereinbefore defined are employed.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed (as communicated to me
from abroad), I declare that what I claim is :-
The process for producing, on cotton, fast shades with or without a silky lustre,
by means of Cachou de Laval, Katigen Black-Brown, Noir Vidal, Verde Italiano,
Fast Black, or analogous dye-stuffs, which process consists in dyeing the unmordanted
cotton fibre, either in the ordinary or in a stretched state, with the said colouring
matters, in cold strong alkaline baths.
DL 1
1007