New Blue and Bluish-green Colouring Matters, and the Process for their Manufacture.
Year: 1892

page_text: Date of Application, 9th Aug., 1892
Complete Specification Left, 8th May, 1893-1ccepted, 10th June, 1893
PROVISIONAL SPECIFICATION.
New Blue and Bluish-green Colouring Matters, and the Process for
their Manufacture.
We, BROOKE, SIMPSON AND SPILLER, LIMITED, of Atlas Works, Hackney
Wick, in the County of Middlesex, Aniline Dye Manufacturers, and ARTHUR
GEORGE GREEN, F.I.C., F.C.S., Chemist to the said Brooke, Simpson and Spiller,
Limited, do hereby declare the nature of this invention to be as follows
1
This invention relates to the discovery of a new class of blue and bluish-green
colouring matters, and to the process for their manufacture. The said colouring
matters are the mono- di- and tri-sulphonic acids of dibenzyldiamidophenylditolyl-
They are obtained by the following methods:
I. By condensation of benzaldehyde (1 mol.) with monobenzylorthotoluidine
(2 mols.), sulphonation of the leuco base (dibenzyldiamidophenylditolylmethane)
and oxidation of the sulphonic acid obtained.
II. By oxidation of the leuco base obtained in I, and subsequent sulphonation of
the colour.
III. By condensation of benzaldehyde (1 mol.) with monobenzlorthotoluidine-
monosulphonic acid (2 mols.) and oxidation of the leuco-sulphonic acid obtained.
IV. By further sulphonation of the leuco-sulphonic acid obtained under III and
subsequent oxidation.
V. By further sulphonation of the colouring-matter obtained under III.
The condensations take place very readily and may be effected by employing any
of the usual condensing agents such as zinc chloride, sulphuric acid, hydrochloric
acid, oxalic acid, etc. In the case of the monobenzylorthotoluidinemonosulphonic
acid, the condensation takes place by merely boiling the two constituents together
in aqueous solution.
The oxidation of the leuco-bases and leuco-sulphonic acids into the colouring
matters, is performed by means of the ordinary oxidising agents, such as lead
peroxide, manganese dioxide, potassium bichromate, potassium permanganate, etc.
employed in acid solution.
Monobenzylorthotoluidine, CH(CH) NH CH₂CH, which does not appear
to have been hitherto described, is prepared by heating equal molecular proportions
of orthotoluidine and benzylchloride, in presence of aqueous caustic soda. It is a
white crystalline solid, which melts at 60° C. and boils at 313° C.
Monobenzylorthotoluidinemonosulphonic acid is obtained by dissolving mono-
benzylorthotoluidine in fuming sulphuric acid, at a low temperature. It is sparingly
soluble in water, from which it separates as a crystalline precipitate on dissolving
the product of sulphonation in water, and allowing it to stand.
The following two examples may be given, to illustrate the method of producing
colouring-matters according to this invention, but we do not bind ourselves to the
details employed, as these may be varied as above mentioned
:-
A. A mixture of 39 lbs. of monobenzylorthotoluidine, 10 lbs. of benzaldehyde,
and 10 lbs. of concentrated sulphuric acid, are heated at 100°-120° C. for .3 or
4 hours. The product is boiled with water and basified with caustic soda. The
leuco-base thus obtained is dried, ground, and dissolved in 100 lbs. of concentrated
sulphuric acid, and fuming sulphuric acid of 70% SO, is added until a drop taken
[rice 8d l

page_text: out is soluble in warm water. The product is poured into water, neutralised with
lime and filtered from calcium sulphate. The calcium salt is converted into sodium
salt, and the solution of the latter is oxidised .in the cold by adding 24 lbs. of lead
peroxide and 12 lbs. of sulphuric acid. After filtering from lead sulphate the
solution of the colouring matter is evaporated to dryness. It dyes wool and silk a
bluish-green from an acid bath.
B. 39 lbs. of monobenzylorthotoluidinė are dissolved in 80 lbs. of concentrated
sulphuric acid and carefully sulphonated at a low temperature (40°-50° C.) by
the slow addition of fuming sulphuric acid, until a drop taken out is soluble in
alkalies. The product is poured into water, and the sulphonic acid, which
cystallises out on standing, is washed and dried. 47 lbs. of this sulphonic acid
are suspended in 50 gals. of water, 10 lbs. of benzaldehyde are added and the
mixture is boiled for several hours with an inverted condenser. On cooling the
leuco-sulphonic acid, separates out. It is dissolved in 200 gals. of water, together
with sufficient sodium carbonate to make it slightly alkaline; 10 lbs. of potassium
bichromate are then added, and the solution is acidified with sulphuric acid and
stirred until the formation of the colouring matter is complete. The latter
separates as a bronzy precipitate, which is dissolved in just sufficient sodium
carbonate, filtered, and the colour precipitated by the addition of salt, filtered off
and dried. It dyes wool and silk a beautiful greenish-blue from an acid bath.
Dated this 9th day of August 1892.
AMBROSE MYALL,
21, Cockspur Street, London, S. W., Agent for the Applicants.
COMPLETE SPECIFICATION.
New Blue and Bluish-green Colouring Matters, and the Process for
their Manufacture.
We, BROOKE SIMPSON & SPILLER LIMITED, of Atlas Works, Hackney Wick,
in the County of Middlesex, Aniline Dye Manufacturers, and ARTHUR GEORGE
GREEN, F.I.C., F.C.S., Chemist to the said Brooke Simpson & Spiller Limited,
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:―
This invention relates to the discovery of a new class of blue and bluish-green
colouring matters, and to the process for their manufacture. The said colouring
matters are the mono- di- and tri-sulphonic acids of dibenzyldiamidophenylditolv】- 3

page_text: chloride, or any other suitable condensing agent, but in the case of the mono-
benzylorthotoluidinemonosulphonic acid (see methods III, IV, & V) the
condensation takes place by merely boiling the two constituents together in
aqueous solution, no condensing agent being requisite.
The oxidation of the leuco-bases and leuco-sulphonic acids into the colouring
matters, is performed by means of the ordinary oxidising agents, such, for example,
as lead peroxide, manganese dioxide, potassium bichromate, or potassium perman-
ganate, employed in acid solution.
Monobenzylorthotoluidine C.H(CH) NH CH,C,H,, which does not appear
to have been hitherto described, is prepared by heating equal molecular proportions
It is a
of orthotoluidine and benzylchloride in presence of aqueous caustic soda.
white crystalline solid, which melts at 60° C. and boils at 313° C.
Monobenzylorthotoluidinemonosulphonic acid is obtained by dissolving mono-
benzylorthotoluidine in fuming sulphuric acid at a low temperature. It is sparingly
soluble in water, from which it separates as a crystalline precipitate on dissolving
the product of sulphonation in water and allowing it to stand.
The following two examples may be given to illustrate the method of producing
colouring matters according to this invention, but we do not bind ourselves to the
details employed, as these may be varied as above mentioned.
As an example, according to the process given under method I, a mixture
of 10 lbs. of benzaldehyde, 39 lbs. of monobenzylorthotoluidine and 10 lbs. of
concentrated sulphuric acid are heated at 100°-120° C. for 3 or 4 hours. The
product is boiled with water and basified with caustic soda. The leuco-base thus
obtained is dried, ground and dissolved in 100 lbs. of concentrated sulphuric acid,
and fuming sulphuric acid of 70% SO, is added until a drop taken out is soluble
in warm water. The product is poured into water, neutralised with lime and
filtered from calcium sulphate. The calcium salt is converted into sodium salt and
the solution of the latter is oxidised in the cold, by adding 24 lbs. of finely divided
lead peroxide and 12 lbs. of concentrated sulphuric acid. After filtering from lead
sulphate the solution of the colouring matter is evaporated to dryness. It dyes
wool and silk a bluish-green from an acid bath.
As an example, according to the process given under method III, 39 lbs. of
monobenzylorthotoluidine are dissolved in 80 lbs. of concentrated sulphuric acid
and carefully sulphonated at a low temperature (40°-50° C.) by the slow addition
of fuming sulphuric acid, until a drop taken out is soluble in alkalies. The product
is poured into water and the sulphonic acid, which crystallises out on standing, is
washed and dried.
47 lbs. of the sulphonic acid are suspended in 50 gals. of water, 10 lbs. of
benzaldehyde are added and the mixture is boiled for several hours with an
inverted condenser. On cooling, the leuco-sulphonic acid separates out. It is
dissolved in 200 gals. of water together with sufficient sodium carbonate to make
it slightly alkaline, 10 lbs. of potassium bichromate are then added and the solution
is acidified with sulphuric acid and stirred until the formation of the colouring
matter is complete. The latter separates as a bronzy precipitate which is dissolved
in just sufficient sodium carbonate, filtered and the colour precipitated by the
addition of salt, filtered off and dried. It dyes wool and silk a beautiful greenish-
blue from an acid bath.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that
what we claim is :-
1. The production of a new class of blue and bluish green colouring matters,
which are mono-di- or tri-sulphonic acids of dibenzyldiamidophenylditolylcarbinol,
or salts of such sulphonic acids.
2. The process for the preparation of a colouring matter, consisting of the con-
densation of 1 molecule of benzaldehyde with 2 molecules of monobenzylortho-
toluidine, sulphonation of the leuco base (dibenzyldiamidophenylditolylmethane) thus

page_text: obtained, and finally oxidation of the leuco-sulphonic acid thus produced, substan-
tially as described.
3. The process for the preparation of a colouring matter, consisting of the con-
densation of 1 molecule of benzaldehyde with 2 molecules of monobenzylortho-
toluidine, oxidation of the leuco-base thus obtained, and subsequent sulphonation of
the insoluble colour, substantially as described.
4. The process for the preparation of a colouring matter, consisting of the con-
densation of 1 molecule of benzaldehyde with 2 molecules of monobenzylortho-
toluidinemonosulphonic acid and oxidation of the leuco-sulphonic acid so obtained,
substantially as described.
5. The process for the preparation of a colouring matter, consisting of the con-
densation of molecule of benzaldehyde with 2 molecules of monobenzylortho-
toluidinemonosulphonic acid, further sulphonation of the leuco-sulphonic acid so
obtained and subsequent oxidation of the product, substantially as described.
6. The process for the preparation of a colouring matter, consisting of the con-
densation of 1 molecule of benzaldehyde with 2 molecules of monobenzylortho-
toluidinemonosulphonic acid, oxidation of the leuco-sulphonic acid so obtained, and
further sulphonation of the colouring matter produced, substantially as described.
7. As new articles of manufacture the colouring matters obtained by the processes
herein described.
Dated this 8th day of May 1893
AMBROSE MYALL,
21, Cockspur Street, London, S.W., Agent for the Applicants.