Improvements in Colouring Matters.
Year: 1893

page_text: Date of Application, 15th Aug., 1893
Complete Specification Left, 25th Apr., 1894-Accepted, 25th May, 1894
PROVISIONAL SPECIFICATION.
Improvements in Colouring Matters.
I, RUPERT GREVILLE WILLIAMS, of Greenfield House, Heywood, Manchester,
in the County of Lancaster, Manufacturing Chemist, do hereby declare the nature
of this invention to be as follows:-
This invention relates to a new and improved process for combining tetrazo
compounds of meta phenylene-diamine or its homologues with hereinafter mentioned
phenols. The colouring matters thus produced have the valuable property of
dyeing unmordanted cotton in an alkaline or neutral bath. In the Specification of
Letters Patent 1593 1888, there is described a method for obtaining somewhat
similar products, but it was found that the results were very irregular when the
process was carried out on a large scale, in consequence of the extremely low
temperatures at which it was necessary to conduct the reactions. By using this
present improved process, however, the necessity for employing such inconvenient
and costly low temperatures is eliminated.
The following examples will serve as illustrations.
EXAMPLE I.
10.8 lbs. of meta phenylene-diamine are dissolved in about 350 lbs. of water
Then solutions of about 60 lbs. of caustic soda, 14 lbs. of nitrite of soda, and 11 lbs.
of resorcine are added. The temperature is lowered to about 5° C. with ice and the
mixture is kept vigorously agitated. Dilute hydrochloric acid is then very slowly
run in until the reaction is completed. It is necessary that the mixture must be
kept strongly alkaline during the whole operation, and therefore a solution of
caustic soda should be introduced from time to time if necessary. When the
reaction is completed, an excess of hydrochloric acid is added to precipitate the
colour which is then filtered off, washed, and dried down at a low temperature with
enough caustic alkali to render it soluble in water.
This product dyes unmordanted cotton a rich brown in an alkaline bath with or
without common salt.
EXAMPLE II.
I molecule of meta toluylene-diamine + 2 molecules of nitrite of soda + 1 mole-
cule of beta naphthol. This colour, which is insoluble, is sulphonated in the usual
manner, and then dyes cotton a brown-red.
PHILLIPS & LEIGH,
Agents for the Applicant.
PHILLIPS & LEIGH,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Colouring Matters.
I, RUPERT GREVILLE WILLIAMS, of Greenfield House, Heywood, Manchester,
in the County of Lancaster, Manufacturing Chemist, 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 consists in an improved process for combining tetrazo
Price 8d1

page_text: compounds of meta-phenylene-diamine or its homologues with hereinafter mentioned
phenols by which improved colouring matters are produced. These latter have the
valuable property of dyeing unmordanted cotton in an alkaline or neutral bath.
In the British Patent No. 1593, 2nd February 1888, granted to Henry H. Leigh
for an invention communicated to him by myself, there is described a process for
obtaining colouring matters somewhat similar to those which the present invention
yields, but it was found that the results of the said process were very irregular when
it was carried out on a large scale. The cause of this irregularity was the
extremely low temperature at which it was necessary to conduct the reactions, to
prevent the tetrazo-benzene or tetrazo-toluene from almost immediate decomposition,
but even at 10° C. a large quantity decomposed before it could be introduced into
the alkaline phenol, or phenol and acetate of soda. These extremely low.
temperatures were both inconvenient and costly, and the necessity of using them is
obviated by the present invention. As the tetrazo bodies are formed in presence
of the phenols and are, therefore, instantly transformed into their respective.
colouring matters, it is better, however, even with this improved process to keep
the temperature as low as possible.
-
The following examples will serve as illustrations of the said present invention.
EXAMPLE I.
10.8 lbs. of meta-phenylene-diamine are dissolved in about 350 lbs. of water and
solutions of about 60 lbs. of caustic soda, 14 lbs. of nitrite of soda, and 11 lbs. of
resorcine are added. The temperature is lowered to about 5° C. with ice and the
mixture is kept vigorously agitated. Dilute hydrochloric acid is then very slowly
run in until the reaction is completed. It is necessary that the mixture should be
kept strongly alkaline during the whole operation, and therefore a solution of
caustic soda should be introduced from time to time, if necessary. When the
reaction is completed, an excess of hydrochloric acid is added to precipitate the
colour which is then filtered off, washed and dried down at a low temperature with
enough caustic alkali to render it soluble in water. This produci dyes unmordanted
cotton a rich brown in an alkaline bath with or without common salt.
EXAMPLE II.
1 molecule of meta-toluylene-diamine + 2 molecules of nitrite of soda + 1 mole-
cule of beta naphthol. In this example, the resorcine of Example I is substituted
for beta-naphthol, and the resultant colour, which is insoluble, is sulphonated in the
usual manner, and will then dye cotton a brown-red.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The hereinbefore described process of combining tetrazo compounds of meta-
phenylene-diamine or of its homologues with the phenols, resorcine, orcin, alpha-
and beta-naphthol as well as the mono- or di-sulpho acids of these phenols.
Dated this 25th day of April 1894
PHILLIPS & LEIGH,
22, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.