Improved Manufacture of Dry Alizarine.
Year: 1894

page_text: Date of Application, 15th Mar., 1894
Complete Specification Left, 15th Dec., 1894-Accepted, 19th Jan., 1895
[Communicated from abroad by THE FARBWERKE, vormals MEISTER LUCIUS
AND BRUNING, of Hoechst a/ Main, in the Empire of Germany, Chemical
Manufacturers.]
Improved Manufacture of Dry Alizarine.
I, OLIVER IMRAY, of No. 28 Southampton Buildings, in the County of
London, Chartered Patent Agent, do hereby declare the nature of this invention
to be as follows:-
The methods for producing dry 'alizarine which on being treated with water,
takes again the form of paste, are founded on the addition of glycerine or easily
soluble indifferent salts to the alizarine paste that is to be dried. The first method
described in the German Patent of Dr. Leverkus & Söhne dated 7th February
1886 permits of the production of dry alizarine of not more than 85 per cent.;
the second method by addition of indifferent salts according to a Patent which
became void in March 1888 permits of the production of dry alizarine in pieces
containing from 60 to 66 per cent. of alizarine, but an alizarine in pieces
containing below 60 per cent. cannot be produced by the process.
Although it was very desirable, principally for the export to the tropics, that
means should be found for substituting for the alizarine paste an alizarine in
pieces that contained not more than forty or thirty per cent. of alizarine, all
endeavours have failed up to the present time.
Dry alizarine in powder of various percentages which was intended as a
substitute for the alizarine paste, did not meet with approval in the tropics and
especially not in the Indies.
My foreign correspondents have discovered that alizarine in pieces of any
desired percentage can be produced by using starch as diluting agent. The
alizarine in pieces produced in this way resumes the paste form on being treated
with water, and the starch has not the slightest unfavourable influence in the
dyeing process.
Example: 1000 parts by weight of alizarine paste of 20 per cent. are introduced
while stirring, together with 466 parts by weight of dry starch having beforehand
been finely divided in water, into about 3000 parts by weight of cold water and
while continuing to stir, this mixture is freed as much as possible from the water
by means of a filter press. The cakes removed from the filter press are dried
first at low temperature and afterwards at higher temperature.
The yield is 666 parts by weight of alizarine of 30 per cent. in the form of solid
compact pieces of conchoidal fracture resembling that of dry starch.
Dated this 15th day of March 1804
ABEL & IMRAY,
Agents for the Applicant.

page_text: Improved Manufacture of Dry Alizarine.
I, OLIVER IMRAY, of No. 28, Southampton Buildings, in the County of
London, Chartered Patent Agent, 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 methods for producing dry alizarine which on being treated with water,
takes again the form of paste, are founded on the addition of glycerine or easily
soluble indifferent salts to the alizarine paste that is to be dried. The first method
described in the German Patent of Dr. Leverkus & Söhne dated 7th February
1886 permits of the production of dry alizarine of not more than 85 per cent.;
the second method by addition of indifferent salts according to a Patent which
became void in March 1888 permits of the production of dry alizarine in pieces
containing from 60 to 66 per cent. of alizarine, but an alizarine in pieces containing
below 60 per cent. cannot be produced by the process.
Although it was very desirable, principally for the export to the tropics, that
means should be found for substituting for the alizarine paste an alizarine in
pieces that contained not more that forty or thirty per cent. of alizarine, all
endeavours have failed up to the present time.
Dry alizarine in powder of various percentages which was intended as a
substitute for the alizarine paste, did not meet with approval in the tropics and
especially not in the Indies.
My foreign correspondents have discovered that alizarine in pieces of any
desired percentage can be produced by using starch as diluting agent. The
alizarine in pieces produced in this way resumes the paste form on being treated
with water, and the starch has not the slightest unfavourable influence in the
dyeing process.
Example: 1000 parts by weight of alizarine paste of 20 per cent. are introduced
while stirring, together with 466 parts by weight of dry starch having beforehand
been finely divided in water, into about 3000 parts by weight of cold water and
while continuing to stir, this mixture is freed as much as possible from the water
by means of a filter press. The cakes removed from the filter press are dried
first at low temperature and afterwards at higher temperature.
The yield is 666 parts by weight of alizarine of 30 per cent. in the form of solid
compact pieces of conchoidal fracture resembling that of dry starch.
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
claim is :-
1. The manufacture of dry alizarine in pieces having any percentage of
alizarine required, by mixing alizarine paste with cold water and a suitable
quantity of finely divided starch, bringing the mixture into the form of cakes by
filtration in presses and drying the cakes at low temperature, substantially as
described.
2. As a new manufacture, a compound of dry alizarine and starch in the form
of solid pieces, cakes or lumps substantially as described.
Dated this 15th day of December 1894.
ABEL & IMRAY,
Agents for the Applicant.