Improvements in the Manufacture or Production of an Albumen- tannin Compound.
Year: 1896

page_text: Date of Application, 23rd Mar., 1896-Accepted, 25th Apr., 1896
COMPLETE SPECIFICATION.
Improvements in the Manufacture or Production of an Albumen-
tannin Compound.
A communication from Messrs. KNOLL & Co., of Ludwigshafen on the Rhine,
Germany, Chemical Manufacturers."
I, WILLIAM LLOYD WISE, of 46 Lincoln's Inn Fields, in the County of
London, Consulting Engineer and 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 :-
In employing tannic acid as an astringent, it is highly desirable to use it in a
form in which it is insoluble in or unaffected by the juices of the stomach and so
that it shall be effective only in the intestines. In using tannic acid in the form
heretofore usually sold for producing an astringent action on the mucous membrane
of the intestines, the stomach is affected, which is objectionable because, in taking
the astringent for a lengthened period, it is liable to cause indigestion. Further-
more, in consequence of the absorption of the easily soluble tannic acid in the
stomach, part only of that originally taken can arrive at the place where its
astringent properties are desired to act. A compound of tannic acid therefore,
that is insoluble in the stomach, will have no effect in the stomach, and will escape
absorption therein to be afterwards dissolved and come into effect in the intestines
only.
Now this invention relates to a process whereby the albumen compound of
tannic acid is rendered indifferent to or unaffected by the juices of the stomach.
While albuminate of tannin, if employed in a freshly precipitated state, will be
digested in an effective gastric juice within a few minutes, and while the powder of
such compound, if air dried, will be completely dissolved within about two hours,
the same quantity of the preparation if heated for six to ten hours up
to 110° Centigrade and above, will hardly be attacked by the gastric juice, even
within twenty-four hours.
This last preparation of tannic acid is therefore highly appropriate for use in
the intestines, as the entire tannin, taken in this form, will be available for use
therein, and even when used for a prolonged period will not affect the mucous
membrane of the stomach.
For manufacturing the above characterized albumen-tannin compound or
albuminate of tannin the precipitate obtained in the well known manner by mixing
aqueous solutions of tannic acid and albumen is used. The following method of
manufacturing albuminate of tannin according to this invention has been found to
give satisfactory results.
Ten kilogrammes of albumen and twenty kilogrammes of tannic acid are
dissolved separately in cold distilled water and the solutions are afterward slowly
mixed whilst being continually stirred. The mixture being allowed to settle, the
supernatent solution is decanted, and the precipitate is then freed, by repeated
lixiviation, from any surplus tannic acid and is afterwards filtered, pressed aud
dried, and is finally heated during a period of from about six to ten hours at
a temperature of about one hundred and ten degrees Centigrade or it may be above
this temperature up say to about one hundred and fifty degrees Centigrade.
The weight of the albumen-tannin compound thus obtained will be about ten
kilogrammes. The heating may be effected in the usual manner within an air

page_text: bath, with or without the aid of a vacuum; or the moist precipitate, or the
precipitate dried at a moderate heat, may be heated to the required temperature in
a liquid that has no action upon it, such for instance as toluof or xylol, for several
hours, as much as possible of the said liquid being afterwards poured off from the
precipitate, and the remainder being removed by evaporation.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. The manufacture of an albumen-tannin compound or albuminate of tannin
insoluble in the stomach but effective in the intestines, by heating the precipitate
obtained by mixing a solution of albumen with a solution of tannin, to a
temperature of from about 110° to 150° Centigrade, substantially as herein
described.
2. The new or improved albumen-tannin or albuminate of tannin herein
described, having the property of resisting the action of the juices of the stomach
but being readily active upon the mucous membrane of the intestines.
Dated this 23rd day of March 1898.
Dated this
For the Applicant,
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.