An Improved Process of Printing on Aniline Black.
Year: 1895

page_text: Date of Application, 5th June, 1895-Accepted, 6th July, 1895
[Communicated from abroad by Dr. HuGO SCHWEITZER, of 159 Front Street,
and EDWARD NICOLL DICKERSON, of 64 East 34th Street, both in New
York, United States of America, Chemists.]——
An Improved Process of Printing on Aniline Black.
HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, 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:-
My invention consists in the production of colored patterns or figures on anilin
black grounds by printing on the cloth a mixture, which, during the process of the
application and development of anilin black, does not only prevent the formation of
black on the printed parts, but produces itself a color.
If I take, for example, the nitrosamin from the diazo compound of paranitranilin,
in itself no color, and mix it with the sodium salt of beta naphthol and oxide of
zinc and a proper thickening, as hereinafter described, and print this mixture on
white cloth which is afterward dyed with any of the known anilin black mixtures,
the acid present and generated during the development of anilin black produces a
red color from the nitrosamin and beta naphthol, and we obtain a red pattern on
black ground.
Heretofore in using the nitrosamin compound for the production of red figures on
anilin black grounds, it has been found that a certain decomposition sets in and that
no orange or red can be obtained if the ordinary resist mixtures are used. (See
Faerber Zeitung, January 1, 1895.) Using, however, as I do, oxide of zinc in the
mixture, it is possible to produce very fast red figures on the black ground.
Instead of the above nitrosamin compound other nitrosamins may be used, and
instead of the beta naphthol other chemicals, such as resorcin, metaphenylene-
diamin, naphthionic acid, amidonaphtholsulfo acid, salicylic acid and resorcylic
acid, which are usually employed for developing colors on the fiber, may be applied,
and thus quite a variety of colors may be produced.
Instead of printing the above mixture first and afterwards applying the anilin
black, I can apply the anilin black first, according to any of the methods well
known to the dyers and calico printers, and then print the mixture on the material.
The anilin black is in either case then developed by passing the cloth through an
anilin-aging machine, or by steaming with or without pressure, and then the cloth
is dried and finished in the usual manner.
Very frequently the developed color becomes brighter and faster if a very small
quantity of nitrite of soda is added to the mixture to be printed on, the nitrosamin
being thus more conveniently converted into the diazo compound.
To carry out my invention, I proceed as follows: I take fifty grams of beta
naphthol finely comminuted, which are stirred into fourteen grams of caustic soda
dissolved in very little water. The mixture is then made up into a thick paste with
gum tragacanth solution. Then fifty-eight grams paranitrophenylnitrosamin cr
seventy-two grams of the sodium salt (with one molecule of water of crystallization)
or the equivalent amount of the commercial paste are mixed together with guni
tragacanth solution. These two mixtures are then stirred together and about two
to three kilos. of oxide of zinc are added and enough gum tragacauth solution is
mixed with it to make the whole mass of the consistency of a good printing color.

page_text: This mixture is then printed on the cloth as a resist or discharge with anilin black,
in the well known manner.
I do not restrict myself to the above given quantities, but mean to include any
reasonable change of the proportions.
When in this Specification I refer to nitrosamin, I mean thereby to refer also to
all its equivalents, namely, compounds of a similar nature, in themselves no
dyestuffs, which, however, during the subsequent treatment are converted into
colors.
When I refer to beta naphthol in this application, I refer also to the described
equivalents.
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 by
my foreign correspondents, I declare that what I claim is :-
The process of producing colored patterns or figures on anilin black grounds
by printing a mixture of nitrosamin, sodium salt of beta naphthol, oxide of zinc
and a proper thickening on the cloth, and applying anilin black thereto, substantially
as described.
Dated this 5th day of June 1805
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.