A Process for Dyeing Wool with Fast Colours.
Year: 1893

page_text: Date of Application, 10th May, 1893
Complete Specification Left, 10th Feb., 1894-Accepted, 5th May, 1894
PROVISIONAL SPECIFICATION.
[Communicated from abroad by THE FARBWERKE vormals MEISTER LUCIUS
AND BRUNING, of Hoechst a/ Main, Germany, Chemical Manufacturers.]
A Process for Dyeing Wool with Fast Colours.
J, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery
Lane, in the County of London, Consulting Engineer and Chartered Patent
Agent, do hereby declare the nature of this invention to be as follows:-
My foreign correspondents have discovered that the azo-colouring matters
derived from alpha naphthole are well suited for dyeing wool fibre with very fast
colours ranging from brown to red brown, when the wool treated with these bodies
is subsequently treated with chromic acid.
Into a vessel containing 2 to 3 cubic metres of water is introduced the solution
of 4 kilos. of colouring matter prepared from diazotised naphthionic acid and alpha
naphthole also 4 kilos. of sulphuric acid and 10 kilos. of Glauber's salt. The
merino previously cleaned and wetted is introduced at about 50° C. and the
temperature is raised to boiling, the fabric being thus dyed orange. After boiling
for three quarters of an hour 3 kilos. of potassium bichromate are added and the
boiling is continued for three quarters of an hour longer. The colour gradually turns
into a beautiful deep dark brown.
The effect obtained is surprising. The dye, which before the addition of the
bichromate was very sensitive to acids and alkalies, is rendered fast against any
alkalies, against fulling and washing and also against acids.
Instead of oxidizing in the dye bath, the colour may be developed by the
potassium bichromate in a separate bath, with or without addition of acid.
Dated this 10th day of May 1893.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
A Process for Dyeing Wool with Fast Colours.
I, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery Lane,
in the County of London, Consulting Engineer and Chartered 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:-
My foreign correspondents have discovered that the azo coloring matters derived
from alpha naphthole are well suited for dyeing wool fibre with very fast colours
ranging from brown to red brown, when the wool treated with these bodies is
subsequently treated with chromic acid.

page_text: Into a vessel containing 2 to 3 cubic metres of water is introduced the solution
of 4 kilos. of coloring matter prepared from diazotised naphthionic acid and alpha
naphthole also 4 kilos. of sulphuric acid and 10 kilos. of Glauber's salt.
The merino previously cleaned and wetted, is introduced at about 50° C. and the
temperature is raised to boiling, the fabric being thus dyed orange. After boiling
for three quarters of an hour, 3 kilos. of potassium bichromate are added and the
boiling is continued for three quarters of an hour longer. The colour gradually
turns into a beautiful deep dark brown.
The effect obtained is surprising. The dye which, before the addition of the
bichromate, was very sensitive to acids and alkalies, is rendered fast against any
alkalies, against fulling and washing and also against acids.
Instead of oxidizing in the dye bath, the colour may be developed by the
potassium bichromate in a separate bath with or without addition of acid.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The herein described process for dying wool with fast colours by treatment with
azo colouring matters derived from alpha naphthole and chromic acid.
Dated this 7th day of February 1894.
ABEL & IMRAY,
Agents for the Applicant.