Dyeing and Printing.
Year: 1885

page_text: Dyeing and Printing.
We Dr HUGO HASSENCAMP of Elberfeld Germany Chemist and FARBENFABRIKEN
VORM FRIED BAYER & C° (H. Bottinger and H. Konig, Directors) of Elberfeld
Germany manufacturing Chemists do hereby declare the nature of said Invention
to be as follows:-
This Invention relating to the manufacture of coloring matter for dyeing and
printing has for its object producing a satisfactory substitute for the relatively
expensive preparations of indigo heretofore employed.
We have discovered certain dyes or coloring matters derived from the leuco
bases known by the name of psuedoleucaniline which comply with the necessary
conditions.
The materials employed in obtaining these products consist of the nitro-leuco
bases resulting from the condensation of meta nitro benzaldehyde with alkalized
anilines and the amido leuco bases obtained by the reduction of the same or psuedo
leucaniline.
In carrying out our Invention we introduce benzyl groups into the aforesaid
amido bases (tetra methyl psuedoleucaniline and its homologues) convert the
benzylised bases into leuco-sulpho-acids and convert the latter into coloring sulpho-
acids (sulpho acids or dye stuffs) by oxidation-A dye is thereby obtained which
dyes wool uniformly in an acid bath alone or mixed with other dyes and is very
fast-As practically useful materials to be employed may be mentioned the
products of the condensation of metanitrobenzaldehyde with dimethylaniline
diethylaniline monomethylaniline monoethylaniline methylbenzylaniline and ethyl-
benzylaniline and the amido bases obtained by the reduction thereof.
In order to produce a blue dye for example according to this Invention say
about fifty kilos of tetramethyl-psuedo-leucaniline obtained from metanitrobenzal❤
dehyde for example which is so constituted as to be capable of taking up two
benzylgroups are heated in an autoclave or tightly closed vessel in an oil bath at
a temperature of about 115 degrees Centigrade for from about four to six hours
with about 40 kilos of benzylchloride for example and one hundred and twenty six
kilos of soda lye at about 10 per cent strength. The benzylized base is exposed for
a considerable time to the action of steam in order to remove oily byeproducts and
T

page_text: then dried. A mass brittle when cold and slightly tinged with yellow is thus
obtained which has no tendency to crystallization and is dissolved with difficulty
in diluted mineral acid.
In order to effect the sulphonizing of this product about fifty kilos of the dry
benzylised base are gradually introduced into about two hundred kilos of fuming
sulphuric acid containing from about twenty to twenty eight per cent of anhydride
maintained at a low temperature Directly the dissolution is complete fuming
sulphuric acid is added (the vessel being well cooled externally) until free
anhydride is present and the sulphonizing is then complete. Sulpho acid is treated
in the manner usual in chemistry-The free sulpho acid dissolves with difficulty in
cold water but more readily in hot water in cold solutions of its alkali salts which
are readily soluble in water diluted mineral acids produce a precipitate of the free
sulpho-acid but no precipitate is produced by acetic acid.
The oxidation of the sulpho acid is effected by ordinary or known means with
manganese peroxide of lead or the like. The dye is readily precipitated by means
of common salt from the solution in the form of a dark deposit or precipitate from
the solution which is of a deep blue color and the precipitate when heated fuses
into a mass having a coppery lustre.
When other alkalized anilines are employed in place of the dimethylaniline
referred to in the foregoing example the shade is more yellow in proportion as the
molecular weight is increased but the difference is insignificant.

page_text: Improvements in the Manufacture of Coloring Matters for
Dyeing and Printing.
We Dr HUGO HASSENCAMP of Elberfeld Germany Chemist and FARBENFABRIKEN
VORM FRIED BAYER & C° (H. Bottinger and H. Konig Directors) of Elberfeld
Germany Manufacturing Chemists, 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:-
For some time past dyers have been in want of a dye which could be employed
as a satisfactory substitute for the expensive preparations of indigo. The products
which have been heretofore placed in the market for the purpose of supplying this
want and which to a certain extent have been, not unfavorably received of which
the acid green (Saure grün) or light green acid, (Licht grün S) of commerce deserve
especial mention but imperfectly accomplish the desired object partly on account of
unsuitability of shade and partly because they are not sufficiently fast.
The object of this Invention is to manufacture dyes or colouring matters of the
leuco base known by the name of psuedo leucoaniline which possesses the necessary
properties to enable them to supply the want hereinbefore specified.
The materials employed in obtaining these products consist of the nitro-leuco
bases resulting from the condensation of meta-nitro-benzaldehyde with alkylised
anilines and further of the amido leuco bases obtained by the reduction of the same
and the production of which was discovered by the chemists C and O. Fischer.
These gentlemen describe in Berl Ber vol XII page 802 in the first place the
metatritrotetramethyldiamidotriphemylmethane obtained by the condensation of
meta-nitro-benzoldehyde with dimethylaniline which they converted by reduction
into the corresponding triamido compounds. This reaction was subsequently
modified by O. Fischer and T. Zeigler by using aniline in place of the dimethyl-
aniline and the isomeric leucoaniline thereby obtained was designated psuedo-
leucoaniline see Berl. Ber vol XIII page 671.
Our special process is performed as follows:-
We introduce benzyl groups into the aforesaid amido bases, convert the
benzylised bases into sulpho-acids and convert the latter into coloring sulpho-
acids by oxidation. A green dye is thereby obtained with a decided blue tinge
which is especially advantageous owing to its fastness and the facility with which
it dies wool uniformly in an acid bath alone or mixed with other dyes. As
practically useful materials to be employed in the production of the same may
be mentioned the products of the condensation of metanitrobenzoldehyde with
dimethylaniline, diethylaniline, monomethylaniline, monoethylaniline, methyl-
benzylaniline and ethylbenzylaniline, and the amido bases obtained by the
reduction thereof.
With these materials the benzyl groups are commonly the bearer of or contain
the sulpho groups they also comply with the essential conditions of the general
character of the resulting dye, as they not only render possible the easy and
smooth sulphonization of the leuco base, but also are favorable to the properties of
the finished product, solubility in water for example, which increases in proportion
as the number of the benzyl and solpho groups is increased.

page_text: H
H-
obtained from metanitrobenzoldehyde and dimethylaniline, which is so constituted
as to be capable of taking up two benzyl groups.
A. BENZYLISING.
Fifty kilos of tetramethyl-pseudoleucoaniline are heated in an autoclave or
tightly closed vessel in an oil bath at a temperature of about 115 degrees
Centigrade for from about four to six hours with forty kilos of benzylchloride
and one hundred and twenty six kilos of caustic soda lye at 10 per cent strength.
The benzylised base is exposed for a considerable time to the action of steam in
order to remove oily bye-products and then dried. A mass brittle when cold and
slightly tinged with yellow is thus obtained which has no tendency to crystallisa-
tion and is dissolved with difficulty in diluted mineral acid.
B. SULPHONISING.
Fifty kilos of dry benzylised base are gradually introduced into two hundred
kilos of fuming sulphuric acid containing from twenty to twenty eight per cent of
anhydride maintained at a low temperature. Directly the dissolution is complete
fuming sulphuric acid is added (the vessel being well cooled externally) until free
anhydride is present and the sulphonising is then complete. The sulpho acid is
treated in the manner well known to chemists. The free sulpho acid dissolves
with difficulty in cold water but more readily in hot water; in cold solutions of its
alkali salts which are readily soluble in water diluted mineral acids produce a
precipitate of the free sulpho acid but no precipitate is produced by acetic acid.
C. OXIDATION.
The oxidation of the sulpho acid is effected by ordinary or known means with
manganese peroxide of lead or the like. The dye is readily precipitated by means
of common salt from its deep blue solution in the form of a dark deposit or
precipitate which when heated fuses into a mass having a coppery lustre. It is
sold as a salt of soda.
When other alkylised anilines are employed in place of the dimethylaniline
referred to in the foregoing example the shade is more yellow in proportion as the
molecular weight is increased but the difference is insignificant.
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:—
The bluish-green sulpho acid dye stuffs or colouring matters as herein described
and the process for producing the same by introducing Benzyl groups into tetra-
methylpseudoleucoaniline and its homologues converting the benzylised bases into
leucosulpho acids and converting the latter into sulpho acid dye stuffs by oxidation.
Dated this 9th dass of Santamba- 1000