Production of New Unsymmetrical Diamido Bases, and Manufacture of Dyes therefrom.
Year: 1893

page_text: Date of Application, 28th June, 1893-Accepted, 26th Aug., 1893
COMPLETE SPECIFICATION.
[Communicated from abroad by the Firm of L. DURAND HUGUENIN & Co., of
Basle, Switzerland, Manufacturers.]
Production of New Unsymmetrical Diamido Bases, and Manufacture
of Dyes therefrom.
1, JOHN IMRAY, of No. 28 Southampton Buildings, Chancery Lane, in the
County of London, 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 :-
When in the reaction mixture described in the Specification No. 9360 of 1892,
consisting of one molecule formaldehyde, one molecule tolidine and one molecule
basic tolidine hydrochlorate, one molecule anilin hydrochlorate is substituted for
the basic tolidin hydrochlorate, a new base is obtained having apparently the

page_text: The tetrazo compound soluble in water forms for example with a-naphthol-a-
sulphonic acid a blue dye for cotton.
The production of the above mentioned tetrazo dye from the new diamido bases
above described is effected as follows:-
I. PRODUCTION OF THE DYE BY COMBINING THE TETRAZO COMPOUNDS
OF THE BASE FROM FORMALDEHYDE AND TOLIDIN AND ANILIN WITHI
a-NAPHTHIONIC ACID.
3.2 kilos. of the new base are diazotised by 8 kilos. hydrochloric acid of 21° Bé.
and 1.4 kilos. sodium nitrite.
The tetrazo compound thus obtained is poured with agitation into a solution of
4.9 kilos. naphthionate of soda, and 8 kilos. acetate of soda.
After standing 12 hours the product of the reaction is supersaturated. with
carbonate of soda solution, the mixture is boiled and the dye stuff which is formed
is precipitated from its solution by means of salt. When dried it is a red brown
powder which dyes uumordanted cotton red in an alkaline bath. The solution in
concentrated sulphuric acid is red violet.
II. PRODUCTION OF THE DYE BY COMBINING THE TETRAZO COMPOUND
OF THE BASE FROM FORMALDEHYDE AND DIANISIDINE AND ANILIN
WITH a-NAPHTHOL-a-SULPHONIC ACID.
When
The tetrazo compound obtained from 3-5 kilos. of the new base, 8 kilos. hydro-
chloric acid of 21° Bé., and 14 kilos. sodium nitrite is poured into a solution of
4-5 kilos. a-naphthol-a-sulphonic acid and 6 kilos. carbonate of soda. After standing
for several hours, the mixture is boiled and the dye obtained is salted out.
dried it forms a brown powder with metallic lustre, and dyes unmordanted cotton
blue in an alkaline bath. The solution in concentrated sulphuric acid is grey-blue.
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 :-
1. The herein described process for production of new diamido bases applicable
for manufacture of substantive cotton dyes, by condensing formaldehyde with
hydrochlorate of anilin and tolidin or dianisidin.
2. The new diamido bases produced in the manner above referred to.
3. The herein described process for the manufacture of a red substantive cotton
dye by combining 2 molecules of a-naphthionic acid with 1 molecule of the tetrazo
compound of the diamido base produced as above stated from formaldehyde, tolidin
and anilin.
4. The herein described process for the manufacture of a blue substantive cotton
dye by combining 2 molecules of a-naphthol-a-sulphonic acid with 1 molecule of the
tetrazo compound of the diamido base produced as above stated from formaldehyde,
dianisidin and anilin.
5. The substantive cotton dyes manufactured by the processes set forth in the
3rd and 4th claims.
Dated this 20th day of T1902
ABEL & IMRAY,
Agents for the Applicant.