Improvements in the Treatment and Testing of Gelatinous Matter.
Year: 1894

page_text: Date of Application, 6th Mar., 1894
Complete Specification Left, 6th Dec., 1894-Accepted, 12th Jan., 1895.
PROVISIONAL SPECIFICATION.
Improvements in the Treatment and Testing of Gelatinous Matter.
I, AUGUST ZIMMERMANN, of 6 & 7 Cross Lane, St. Mary-at-Hill, in the City of
London, Merchant, (a communication to me from abroad by The Chemische
Fabrik auf Actien vormals E. Schering, of 170 Müllerstrasse, Berlin,) do hereby
declare the nature of this invention to be as follows:
My correspondents have found that by adding a greater or lesser proportion of
formic aldehyde (CH₂O) or formalin of a given strength to glue or gelatinous
solutions, their degree of hardness and toughness may be tested, and that similarly
any desired degree of hardness and toughness may be produced in gelatine glue or
gelatinous solutions.
:
A liquid gelatinous solution being mixed with a definite quantity of formalin of
the strength of 36 % formic aldehyde will be converted into a jelly which is
insoluble in hot water, for instance 50 ccm. of a 5% gelatine solution requires
0.25 ccm. of formalin.
Liquified gelatine of a certain strength when mixed with certain other
proportions of formic aldehyde, will after cooling produce a jelly which when
re-warmed is easily liquified, but this jelly has a far greater degree of hardness and
toughness than ordinary jelly. The same jelly when dried however will produce a
gelatine insoluble in hot water.
When before drying that jelly is mixed with a further determined minor
proportion of formalin the gelatine so produced after drying is again freely
soluble in hot water.
The jelly so produced will show a very extraordinary degree of toughness.
Dated this 6th day of Merah 1001
COMPLETE SPECIFICATION.
Improvements in the Treatment and Testing of Gelatinous Matter.
I, AUGUST ZIMMERMANN, of 6 & 7 Cross Lane, St. Mary-at-Hill, in the City of
London, Merchant, (a communication to me from abroad by The Chemische
Fabrik auf Actien vormals E. Schering of 170 Müllerstrasse, Berlin) 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:-
My correspondents have observed that dead and living tissues, especially the
skin is converted by formic aldehyde into a peculiar leather-like condition and
thereupon based a tanning process. Further experiments showed that large
masses of tissue of living animals and human beings became necrotic by treatment
with formic aldehyde in consequence of the hardening action of the latter.
Further it has been observed that formic aldehyde is excellently adapted to the
hardening of anatomical preparations, whilst glue and glue-yielding substances
Price RdI

page_text: suffer a peculiar change and hardening by treatment with formic aldehyde. These
observations on the hardening properties of formic aldehyde have already been
published.
If formic aldehyde is added to a liquid gelatine solution, for instance 0.25 cc.
formalin (36 per cent. formic aldehyde solution) to 50 cc. of a 5 per cent. gelatine
solution, the gelatine is converted into a jelly insoluble in water and which cannot
be melted again.
warm water.
It is now discovered that if a certain regulated quantity of formalin is added on
cooling a jelly is obtained which readily liquefies on warming again, but that is
distinguished from ordinary gelatine jellies by an extraordinarily increased
tenacity and power of resistance. Further, if this easily liquefiable but very
tenacious jelly is allowed to dry, a gelatine is obtained that is no longer soluble in
If a still smaller proportion of formic aldehyde is added to the jelly
before drying a gelatine is however obtained which after drying dissolves again
very easily in warm water. The jelly obtained from gelatine thus treated with
formic aldehyde and dried, readily liquefies when warmed and possesses
extraordinary powers of tenacity. Glue behaves in an analogous manner to
gelatine.
The accompanying tables will further explain these observations. From them it
is evident also that with a large excess of formalin, the tenacity of the jelly
decreases very rapidly again after a certain maximum has been passed.

page_text: TABLE II.
A 10 per cent. gelatine solution with 0.0 %, 0.1% 0.2%, 0.4% formalin added
respectively (calculated on dry gelatine) was dried upon glass plates. All the
gelatine dissolved easily in water. 5 per cent. solutions were made and the
firmness of the jellies determined after 24 hours.
1. MANUFACTURE OF SIZE.
The method consists in adding to the glue or gelatine solution in course of
manufacture a small definite quantity of formic aldehyde, which shall effect the
required degree of hardening of the size whilst it completely retains its liquefying
property and which is easily estimated by a preliminary trial. The size can be
employed as usual after congealing.
2. MANUFACTURE OF DRY GLUE OR GELATINE.
A small quantity of formic aldehyde is added to the glue or gelatine solution, so
that the glue or gelatine is still completely soluble in water after drying. This
quantity is either estimated by a preliminary trial or is added in definite
proportions according to the character of the material.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what I
claim is :-
:-
1. In the manufacture of size adding to the glue or gelatine solution so much
formic aldehyde that the congealed jelly liquefies again on warming.
2. In the manufacture of glue or gelatine adding so much formic aldehyde to the
solution before drying that the dried glue or gelatine, after soaking in water,
liquefies again on warming.
Dated this Sixth day of December 1894.
AUG. ZIMMERMANN.