Manufacture of Dyestuffs of the Diphenylnaphthylmethane Series.
Year: 1898

page_text: Date of Application, 17th Oct., 1898
Complete Specification Left 14th June 1899-Accepted. 22nd July, 1899
PROVISIONAL SPECIFICATION.
Manufacture of Dyestuffs of the Diphenylnaphthylmethane Series.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, Chancery
Lane, in the County of London, Chartered Patent Agent, do hereby declare the nature
of this invention (as communicated to me from abroad by The Farbwerke vormals;
Meister Lucius and Brüning, of Hoechst a/Main, in the Empire of Germany, Chemical
Manufacturers) to be as follows:→
Dyestuffs from tetralkyldiamidobenzhydrol and naphthalene a-and B-monosulphonic
acids have been described in the Specification No. 14621 of 1890.
Besides that the leucosulphonic acids do not oxidise smoothly into the correspond-
ing dyestuffs, they are also without practical interest on account of their small affinity
to the fibre.
The dyestuffs can be extracted by the material to be dyed only very imperfectly
from an acid bath, the greater part of the dye remaining in the bath.
According to the above specification the disulphonic acids of naphthalene combine
only with difficulty with hydrols and the manufacture of dyestuffs by means of this
disulphonic acid has hitherto not been carried out.
My foreign correspondents have found that contrary to the statement in the said
specification by adhering to appropriate conditions, naphthalenedisulphonic acids
may also be condensed in quantity into leucodisulphonic acids and further that these
leucodisulphonic acids yield, when oxidised, new dyestuffs, which, besides being fast
to washing and light dye very evenly in the acid bath.
While naphthalenemonosulphonic acids combine completely with hydrols in
presence of concentrated sulphuric acid of 66° Bé. at ordinary temperature, the disul-
phonic acids of naphthalene react only slightly under these conditions, but smoothly
and completely at the temperature of boiling water and especially when no water is
present and monohydrate or weak fuming sulphuric acid is employed instead of con-
centrated sulphuric acid of 66° Beaumé.
The following example illustrates the process
27.0 kilos. of tetramethyldiamidobenzhydrol and 39.0 kilos. of sodium salt of
2:7-naphthalenedisulphonic acid of 85 per cent. strength are well mixed and the
mixture is run into 200 kilos. of monohydrate sulphuric acid while well stirring.
The thickened mass thus resulting is then heated in a boiling water bath until a
sample of it is clearly soluble in diluted ammonia, that is to say, till all hydrol has
disappeared. This takes place after from 5 to 6 hours. The product of reaction is
poured into water and transformed in the usual manner into the calcium or sodium
salt.
For the subsequent oxidation, to a solution of 5.0 kilos. of the leuco-salt thus
obtained in about 40 litres of water is added the calculated quantity of sulphuric acid
and this liquid, while well stirring is poured into 2.04 kilos. of peroxide of lead mixed

page_text: with water. The sulphate of lead is then filtered off and the dye solution is
evaporated to dryness.
The dyestuff forms a copper coloured powder, very easily soluble in water. It
dyes wool in an acid bath a very even green fast to washing and light.
The process is the same for producing other dyestuffs from tetralkyldiamid >benz-
hydrols and naphthalene disulphonic acid by employing instead of tetramethyldiami-
dobenzhydrol mentioned in the example, the equivalent quantity of tetraethyldiami-
dobenzhydrol and instead of the above mentioned 2:7- acid other naphthalene-
disulphonic acids, such as 1 : 3, 1:5, 16, 2: 6-naphthalenedisulphonic acid.
The new dyestuffs differ very little in their properties; they dye yellow-green to
blue-green, the ethyl compounds dyeing yellower than the corresponding methyl
compounds.
All these dyestuffs are characterized by their dyeing evenly and their resisting
power to alkalies and the influence of light.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION (AMENDED).
Manufacture of Dyestuffs of the Diphenylnaphthylmethane Series.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, Chancery
Lane, in the County of London, Chartered Patent Agent, do hereby declare the
nature of this invention (as communicated to me from abroad by The Farbwerke
vormals: Meister Lucius and Brüning, of Hoechst a/Main, in the Empire of
Germany, Chemical Manufacturers) and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
Dyestuffs from tetralkyldiamidobenzhydrol and naphthalene a- and B-monosulphonic
acids have been described in the Specification No. 14621 of 1890.
Besides that the leucosulphonic acids do not oxidise smoothly into the corresponding
dyestuffs, they are also without practical interest on account of their small affuity to
the fibre. The dyestuffs can be extracted by the material to be dyed only very
imperfectly from an acid bath, the greater part of the dye remaining in the bath.
According to the.above Specification the disulphonic acids of naphthalene combine
only with difficulty with hydrols and the manufacture of dyestuffs by means of this
disulphonic acid has hitherto not been carried out.
My foreign correspondents have found that contrary to the statement in the said
Specification, by adhering to appropriate conditions, naphthalenedisulphonic acids
may also be condensed in quantity, into leucodisulphonic acids and further that these
leucodisulphonic acids yield, when oxidised, new dyestuffs, which, besides having
good properties, dye very evenly in the acid bath.
While naphthalenemonosulphonic acids combine completely with hydrols in
presence of concentrated sulphuric acid of 66° Bé. at ordinary temperature, the
disulphonic acids of naphthalene react only slightly under these conditions, but
smoothly and completely at the temperature of boiling water and especially when no
water is present and monohydrate or weak fuming sulphuric acid is employed
instead of concentrated sulphuric acid of 66° Beaumé.
The following example illustrates the process:-
27.0 kilos. of tetramethyldiamidobenzhydrol and 39.0 kilos. of sodium salt of
2: 7-naphthalenedisulphonic acid of 85 per cent. strength are well mixed and the
mixture is run into 200 kilos. of monohydrate sulphuric acid while well stirring. The

page_text: thickened mass thus resulting is then heated in a boiling water bath until a sample
of it is clearly soluble in diluted ammonia, that is to say till all hydrol has
disappeared. This takes place after from 5 to 6 hours. The product of reaction is
poured into water and transformed in the usual manner into the calcium or sodium
salt.
For the subsequent oxidation, to a solution of 5.0 kilos. of the leuco-salt thus
obtained in about 40 litres of water is added the calculated quantity of sulphuric
acid and this liquid, while well stirring, is poured into 2.04 kilos. of peroxide of lead
mixed with water. The sulphate of lead is then filtered off and the dye solution is
evaporated to dryness.
The dyestuff forms a copper coloured powder, very easily soluble in water.
wool in an acid bath a very even green, fast to washing and light.
It dyes
The process is the same for producing other dyestuffs from tetralkyldiamido.
benzhydrols and naphthalene disulphonic acid by employing instead of tetra-
methyldiamidobenzhydrol mentioned in the example, the equivalent quantity of
tetraethyldiamidobenzhydrol and instead of the above mentioned 2: 7- acid other
naphthalene-disulphonic acids, such as 1:3, 1: 5, 16, 2: 6-naphthalenedisul-
phonic acid.
The new dyestuffs differ very little in their properties; they dye yellow-green
to blue-green, the ethyl compounds dyeing yellower than the corresponding methyl
compounds.
All these dyestuffs are characterized by their dyeing evenly and their properties
of fastness.
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 I make no claim
to the combining of tetralkyldiamidobenzhydrols with naphthalenedisulphonic acids,
as that is already known, but what I claim is--
°
1. The herein described manufacture of green dyestuffs of the diphenylnaphthyl-
methane series by combining tetralkyldiamidobenzhydrols with naphthalenedi-
sulphonic acids in the presence of condensation agents to leucodisulphonic acids
and by transforming these leucodisulphonic acids by oxidation into dyestuffs.
3. The dyestuffs manufactured as above set forth.
Dated this 13th day of June 1899.