Manufacture of a New Colouring Matter.
Year: 1894

page_text: Date of Application, 3rd Mar., 1894
Complete Specification Left, 1st Dec., 1894-Accepted, 5th Jan., 1895
Manufacture of a New Colouring Matter.
I, REGINALD EDWARD EVANS of Swans Nest Hotel, Stratford on Avon, in
the County of Warwick, Technical Chemist do hereby declare the nature of this
invention to be as follows:-
:-
This invention relates to the manufacture of a new colouring matter applicable
for colouring liquids, especially wines, spirits and the like.
A saccharine body such as cane or invert sugar or glucose is heated as for
obtaining caramel, with alkaline material such as potassium or sodium hydrate
or carbonate, and the melt is dissolved in water forming a solution which contains
the alkali salt of a deeply coloured body having an acid character. By addition
of acid, usually sulphuric acid, to the solution, the colouring matter is precipitated.
The precipitate is washed with water to remove all traces of acid, and is dried
at a gentle heat.
The matter thus prepared can be used for colouring or when greater purity
is desired it can be dissolved in an alkaline solution and again precipitated by
acid. The colouring matter may be obtained in the form of a paste by only
partially drying the washed precipitate. Or it may be dissolved in spirit and
used in the form of a solution.
Dated this 3rd day of March 1894.
ABEL & IMRAY,
Agents for the Applicant.
I, REGINALD EDWARD EVANS, of Swans Nest Hotel; Stratford on Avon, in
the County of Warwick, Technical Chemist, 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 :—
A saccharine body, such as cane or invert sugar or glucose, is heated in the
usual manner for obtaining caramel with an alkaline material such as potassium or
sodium hydrate or carbonate and the resulting product is dissolved in water
forming a solution which contains the salt of a deeply coloured body possessing an
acid character. By the addition of an acid to the solution the colouring matter is
precipitated. Hydrochloric, nitric, sulphuric or other strong acid may be used,
hydrochloric or sulphuric acid being preferred, and they are added in such
proportions as to give the solution an acid reaction. If the precipitation be
effected in the cold, the colouring matter is obtained in the form of a paste which
may be filter-pressed and sold in this form. If the acid chosen be added to the
solution heated to or above 160° F., the colouring matter is precipitated in a tarry
form. In this case the lumps are roughly broken up, washed with water to remove
traces of acid and dried at a gentle heat usually from 80° to 150° F. the temperature
being carefully regulated so as not to melt the precipitate. It is then ground fine
and sold in the form of a powder.

page_text: If it be desired to further purify the precipitate obtained by either of the above
methods it may be redissolved in an alkaline solution such as potassium or sodium
hydrate or carbonate and again precipitated by strong acid.
Or the precipitate may be dissolved in alcohol of about proof strength and
employed in the form of a solution.
By dissolving the precipitated colouring matter either before or after purification
in dilute ammonia a deep coloured solution is obtained which is as soluble in spirit
as the original solid.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
:
.
1. The herein described manufacture of a colouring matter, by heating a
saccharine body with alkaline material, dissolving the product in water and
precipitating the colouring matter in form of paste by addition of acid to the
cold solution.
2. The herein described manufacture of the colouring matter in form of a
powder, by preparing as above set forth a solution of the saccharine and alkaline
compound, moderately heating the solution, precipitating by addition of acid,
washing, drying and grinding.
3. The herein described manufacture of the colouring matter in form of a
solution, by first preparing the paste as set forth in the first claim, purifying it
if necessary, and dissolving the precipitate in alcohol.
Dated this 1st day of December 1894.
ABEL & IMRAY,
Agents for Applicant.