A Process for Rendering Dry Alizarine Fit for Coloring and Printing Purposes.
Year: 1889

page_text: Date of Application, 14th Nov., 1889
Complete Specification Left, 14th Aug., 1890-Accepted, 20th Sept., 1890
PROVISIONAL SPECIFICATION.
A Process for Rendering Dry Alizarine Fit for Coloring and
Printing Purposes.
1 CARL ROMEN of Charlottenburg, near Berlin, Germany, Editor do hereby
declare the nature of my said invention to be as follows:-
It is a well known fact that alizarine is not used in a dry state but only as a 10
to 20 per cent. paste for when it becomes dry it is proved to give a lesser yield for
colouring and printing purposes. The reason for this is that hitherto by suspending
the dry powder in water the same could not be brought to such a fine division than
after having been precipitated from its sodaic solution.
I have been led after many experiments to the discovery of a process by means of
which dry (100 per cent.) alizarine can be again rendered to a full extent fit for
coloring and printing purposes, so that it will be as productive as the alizarine used
in a pasty consistence in commerce.
My process which is more particularly applicable to red, pink, brown, yellow,
violet and orange alizarine consists in dissolving the dry 100% alizarine by means of
caustic alkali with the addition of borax, this solution being added to the coloring or
printing bath. An acid is now introduced into the bath and so selected that the salt
formed thereby with the solvent should not act injuriously upon the oily or clayey
ground, and the alizarine is precipitated in the finest and most regular state of
division.
The caustic alkalies which I use as solvents are hydrate of soda, hydrate of potash,
ammonia and the like. The acids serving as precipitants are hydrochloric acid, nitric
acid, sulphuric acid, phosphoric acids, boric acid, acetic acid, citric acid as well as
tartaric and oxalic acid. The acid selected depends amongst other conditions upon
the properties of the water and of its contents in lime.
Example. For dyeing 100 kg. of goods, the colour bath must contain about
2000 litres of water. 2 kg. of dried (100%) of powdered alizarine is dissolved in.
fron 15 to 20 litres of warm water to which 1300 cub. cm. of soda lye of 38° B. and
800 gr.
of borax are subsequently added. The solution is now added to the color
bath before mixing therewith any other material which may be required according to
the properties of the water. After the whole mass has been well stirred the alizarine
is precipitated by the addition of 1300 cub. cm. of hydrochloric acid having a specific
gravity of 115 and the bath is acidified with 400 grms. of acetic acid, whereupon
the goods are dyed in the usual manner. The quantity of acetic acid to be added
depends upon the subsequent addition of other materials which as above mentioned
will have to be afterwards added according to the properties of the water.
For printing purposes the process is carried on in a similar manner, only in a more
concentrated form. The solution is added to the printing mass and operated on in
the usual manner.
This process has the advantage that the alizarine can be used in a dry state, whereby
the transport of the 80% of water contained in the alizarine paste heretofore used is
avoided. This causes a great economy in freight and duty. The alizarine will also
be able to be sent in cold weather, which was not the case with the paste. The
process has further this advantage that the alizarine as it is precipitated in the colour
bath has such fine properties that it deposits to the last trace, which is not generally
the case with its 20% paste. Furthermore the powder is easier of manipulation than
the paste and does not dry in when deposited, so that there can be no loss of coloring
inaterial.
Dated this 14th day of Novamban 1980

page_text: COMPLETE SPECIFICATION.
A Process for Rendering Dry Alizarine Fit for Coloring and
Printing Purposes.
I, CARL ROMEN, of Charlottenburg, near Berlin, Germany, Editor, 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 :-
It is a well known fact that alizarine is not used in a dry state but only as a 10
to 20 per cent. paste, for when it becomes dry it is proved to give a lesser yield for
coloring and printing purposes. The reason for this, is that hitherto, by suspending
the dry powder in water the same could not be brought to such a fine division than
after having been precipitated from its sodaic solution.
I have been led after many experiments to the discovery of a process, by means of
which dry (100 per cent.) alizarine can be again rendered to a full extent fit for
coloring and printing purposes, so that it will be as productive as the alizarine used in
a pasty consistence in commerce.
My process which is more particularly applicable to red, pink, brown, yellow,
violet, and orange alizarine consists in dissolving the dry (100 %) alizarine by means
of caustic alkali with the addition of borax, this solution being directly added to the
coloring or printing bath, An acid is now introduced into the bath and so selected
that the salt formed theroby with the solvent should not act injuriously upon the oily
or clayey ground, and the alizarine is precipitated in the finest and mostrogular state
of division.
The caustic alkali which I use as solvents are hydrate of soda, hydrate of potash,
ammonia, and the like. The acids serving as precipitants, are hydrochloric acid,
nitric acid, sulphuric acid, phosphoric acids, boric acid, acetic acid, citric acid as well
as tartaric and oxalic acid. The acid selected depends amongst other conditions upon
the properties of the water and of its contents in lime.
Example. For dyeing 100 kg. of goods, the color bath must contain about
2000 litres of water. 2 kg. of dried (100%) of powdered alizarine is dissolved in
from 15 to 20 litres of warm water to which 1300 cub. cm. of soda lye, of 38° B. and
300 gr. of borax are subsequently added. The solution is now added to the color bath
before mixing therewith any other material which may be required according to the
properties of the water. After the whole mass has been well stirred, the alizarine is
precipitated by the addition of 1300 cub. cm. of hydrochloric acid having a specific
gravity of 1.15 and the bath is acidified with 400 grms. of acetic acid, whereupon the
goods are dyed in the usual manner. The quantity of acetic acid to be added depends
upon the subsequent addition of other materials which as above mentioned will have
to be afterwards added according to the properties of the water.
For printing purposes, the process is carried on in a similar manner, only in a more
concentrated form. The solution is added to the printing mass and operated upon in
the usual manner.
This process has the advantage that the alizarine can be used in a dry state, whereby
the transport of the 80% of water contained in the alizarine paste, heretofore used, is
avoided. This causes a great economy in freight and duty. The alizarine will also
be able to be sent in cold weather, which was not the case with the paste. The
process has further this advantage, that the alizarine as it is precipitated in the color
bath has such fine properties that it deposits to the last trace which is not generally
the case with its 20% paste. Furthermore, the powder is easier of manipulation
than the paste and does not dry in when deposited, so that there can be no loss of
coloring material.
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

page_text: coloring and printing purposes, consisting in dissolving the alizarine by means of
caustic alkalies with the addition of borax, and adding the solution directly to the
color or print bath, and then in introducing an acid the salt formed by which with
the solvent should not act injuriously upon the oily or clayey ground hydrochloric,
nitric, sulphuric, phosphoric, boric, acetic, citric, tartaric, and oxalic acid, the alizarine
being finally precipitated in the finest and most regular state of division."
The 14th day of August. 1890
H. GARDNER,
Per R. Core Gardner,
Patent Agent, 166, Fleet Street, London, Agent for the said Carl Romen.