A Process for Rendering Insoluble Albumen and Albumen-like Matters, Casein, Albumose, and the Products of Conversion of Glue and Gelatine.
Year: 1894

page_text: Date of Application, 4th Dec., 1894
Complete Specification Left, 3rd Sept., 1895-Accepted, 12th Oct., 1895
PROVISIONAL SPECIFICATION.
A Process for Rendering Insoluble Albumen and Albumen-like
Matters, Casein, Albumose, and the Products of Conversion of
Glue and Gelatine.
I, AUGUST ZIMMERMANN, of 6 and 7 Cross Lane, St. Mary-at-Hill, in the City
of London, Merchant, (a communication to me from abroad by The Chemische
Fabrik auf Action (vormals E. Schering) of 170 and 171 Müllerstrasse, Berlin in
the Empire of Germany,) do hereby declare the nature of this invention to be as
follows:-
-
My correspondents have discovered that when a solution in water of blood
albumen, egg albumen or albumen of similar derivation or a solution in water of a
salt of casein, albumose, or the products of conversion of glue and gelatine is
mixed with formic aldehyde and then allowed to dry upon a backing, there remains
a film which no longer sticks and which is quite insoluble in water.
This new observation may be utilized for the most different technical purposes in
all cases in which it is desired to produce an insoluble layer of this kind upon a
backing such for example as a glass plate, a metal plate, paper and the like or to
obtain the body itself disengaged from the backing.
1. RENDERING ALBUMEN INSOLUBLE IN FORMIC ALDEHYDE.
My correspondents have observed that pure solutions of albumen, be it blood or
egg albumen behave quite differently towards formic aldehyde to the unpurified
white of egg obtained from fowl's eggs. If white of egg obtained from a fresh egg
be mixed with formic aldehyde, it retains a transparent gelatinous appearance and
is no longer soluble in water, it is not however the white of egg which is gelatinous
and insoluble in water but only the fine membranes intermixed with it which as is
known render white of egg from fowl's eggs of itself viscous and which belong to
the class of horny substances.
The case is quite different if one starts with a clear solution of albumen.
Any desired quantity of formic aldehyde muy be added to a 10% solution of
albumen, without the same being gelatinized or being rendered insoluble in water
after standing for days. The solution on the contrary remains fluid and clear and
may be further diluted with water without any precipitation taking place. If such
solution be however allowed to dry, the remarkable fact is displayed that the filin
which remains behind has become entirely insoluble and has lost its power of
adhesion.
This process for rendering albumen and albumeu like bodies insoluble may find
application in the most different branches of industry, as for example in photography.
Of course any suitable addition such for example as glycerine, common salt &c. &c.
may be made to the albumen according as its application allows or requires.
The albumen solution may also either before or after the addition of the formic
aldehyde solution be mixed with an alkali or with an acid occasioning no
coagulation.
In the first case the albumen is rendered insoluble in water after drying, by a
small quantity of formic aldehyde, in the latter case the requirite quantities of
formic aldehyde are somewhat greater.

page_text: small quantities of an acid or alkali are converted into a product, which has quite
lost the characteristic properties of glue or gelatine. My correspondents have now
found that these products of decomposition of gelatine on being mixed with formic
aldehyde and subsequently allowed to dry also leave behind an insoluble film.
Here also the methylene blue test shows in a striking manner the difference
between the films treated with formic aldehyde and those not so treated.
To produce a layer insoluble in water from the substitution products of gelatine
you proceed for example in the following manner.
75 grammes of gelatine are dissolved in half a litre of water and the solution
boiled for two days with addition of water. The 4.2 grammes of a 40% formic
aldehyde solution are then added. The solution remains fluid for weeks in spite of
this addition. After drying however the remaining body is insoluble in water.
The substitution product which is produced when gelatine is treated with a little
alkali, acetic acid, oxalic acid &c. behaves in the same way.
In all the cases given in the before mentioned examples one may also proceed in
such a way that the solutions of albumen, albumose, casein and the substitution
products of gelatine and gelatine like bodies without addition of formic aldehyde
are evaporated and then submitted to the action of formic aldehyde and the liquid
absorbed being again evaporated.
Dated this Fourth day of December 1894.
COMPLETE SPECIFICATION.
A Process for Rendering Insoluble Albumen and Albumen-like
Matters, Casein, Albumose, and the Products of Conversion of
Glue and Gelatine.
I, AUGUST ZIMMERMANN, of 6 and 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 and 171 Müllerstrasse, Berlin in
the Empire of Germany,) 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 discovered that when a solution in water of blood
albumen, egg albumen or albumen of similar derivation or a solution in water of a
salt of casein albumose or the products of conversion of glue and gelatine is mixed
with formic aldehyde and then allowed to dry upon a backing, there remains a film
which no longer sticks and which is quite insoluble in water.
This new observation may be utilized for the most different technical purposes
in all cases in which it is desired to produce an insoluble layer of this kind upon
a backing such for example as a glass plate, a metal plate, paper and the like or to
obtain the body itself disengaged from the backing.
1. RENDERING ALBUMEN INSOLUBLE BY FORMIC ALDEHYDE.
My correspondents have observed that pure solutions of albumen, be it blood
or egg albumen behave quite differently towards formic aldehyde to the unpurified
white of egg obtained from fowl's eggs. If white of egg obtained from a fresh
egg be mixed with formic aldehyde, it retains a transparent gelatinous appearance
and is no longer soluble in water, it is not however the white of egg which is
gelatinous and insoluble in water but only the fine membranes intermixed with it
which as is known render white of egg from fowl's eggs of itself viscous and which
belong to the class of horny substances.

page_text: The case is quite different if one starts with a clear solution of albumen. Any
desired quantity of formic aldehyde may be added to a 10% solution of albumen,
without the same being gelatinized or being rendered insoluble in water after
standing for days. The solution on the contrary remains fluid and clear and may
be further diluted with water without any precipitation taking place. If such
solution be however allowed to dry, the remarkable fact is displayed that the film
which remains behind has become entirely insoluble and has lost its power of
adhesion.
This process for rendering albumen and albumen-like bodies insoluble may find
application in the most different branches of industry, as for example in photo-
graphy. Of course any suitable addition such for example as glycerine, common
salt &c. &c. may be made to the albumen according as its application allows or
requires.
The albumen solution may also either before or after the addition of the formic
aldehyde solution be mixed with an alkali or with an acid occasioning no
coagulation.
In the first case the albumen is rendered insoluble in water after drying by a
small quantity of formic aldehyde, in the latter case the requisite quantities of
formic aldehyde are somewhat greater.
To produce a layer of albumen insoluble in water you proceed in the following
way-
1 kilogramme of a 10% solution of albumen ovi sicc. pulv. subt. (pulverized
dried eggs) is mixed with 100 grammes of a 40% solution of formic aldehyde
preferably somewhat diluted beforehand. The solution is then evaporated upon
glass plates or any other backing such as paper, zinc plate &c. The albumen
which after drying has become insoluble is then according to its application either
left upon the backing or removed therefrom.
This process of rendering albumen insoluble is especially of use in photography
in the production and utilization of albumen papers sensitive or not sensitive to
light or which have been sensitive to light.
II. RENDERING ALBUMOSE INSOLUBLE BY FORMIC ALDEHYDE.
Albumose of the most different origins behaves also in exactly the same manner
as albumen. If a solution of albumose be mixed with formic aldehyde it remains
clear for weeks. If it be dried however, a thin film which no longer sticks and
which is insoluble in water remains a sign that complete transformation has taken
place.
III.
RENDERING CASEIN INSOLUBLE BY FORMIC ALDEHYDE.
If for example a 5% solution of alkaline casein be mixed with formic aldehyde,
no coagulation takes place. The solution remains for a long time clear and fluid.
If however the solution be poured upon plates and allowed to dry, a transparent
film of casein remains behind which film is completely insoluble in water.
The difference between samples treated with formic aldehyde and those not so
treated is easily shown in the following manner.
The thin film which remains behind is carefully disengaged from the backing
allowed to somewhat soak in water and a few drops of a solution of inethylene blue
added. If now carefully warmed, a clear blue solution is seen to make its appearance
in the casein samples which are either without or which have had too little formic
aldehyde, whilst a deep blue coloured film is visible in the samples rendered insoluble
by formic aldehyde.
A casein solution in ammonia behaves in a similar manner, but in this case
thickening or precipitation takes place when large quantities of formic aldehyde
are added; moreover clear casein solutions with ammonia may also be produced

page_text: DICH When Sman
leave a thin film which is quite insoluble in water.
To produce an insoluble casein layer you proceed for example in the following
way :-
a. A casein soda solution in 1 litre of water, containing about 100 grammes
casein and about 15 grammes NaOH is mixed with 15 gramines of a 40% formic
aldehyde solution. The solution remains clear. It is then evaporated upon glass
plates or any other backing such as paper, zinc plate &c.
According to the use for which it is required the casein which has become insoluble
after drying is left on the backing or removed from the same. Of course in this
case also different additions may be made.
b. A casein ammonia solution in 2 litres of water containing about 100 grammes
casein and 100 cubic centimetres of a 30% ammonia solution is mixed with
grammes of a 40% formic aldehyde solution and then proceed as in the
a process.
IV. RENDERING THE CONVERSION PRODUCTS OF GLUE AND GELATINE &C.
INSOLUBLE.
As is known glue and gelatine transformed by long heating with water or with
small quantities of an acid or alkali are converted into a product, which has quite
lost the characteristic properties of glue or gelatine. My correspondents have now
found that these products of decomposition of gelatine on being mixed with formic
aldehyde and subsequently allowed to dry also leave behind an insoluble film. Here
also the methylene blue test shows in a striking manner the difference between the
films treated with formic aldehyde and those not so treated.
To produce a layer insoluble in water from the substitution products of gelatine
you proceed for example in the following manner :-
75 grammes of gelatine are dissolved in half a litre of water and the solution
boiled for two days with addition of water. The 42 grammes of a 40%
formic aldehyde solution are then added. The solution remains fluid for weeks
in spite of this addition. After drying however the remaining body is insoluble
in water.
The substitution product which is produced when gelatine is treated with a little
alkali, acetic acid, oxalic acid &c. behaves in the same way.
In all the cases given in the before mentioned examples one may also proceed
in such a way that the solutions of albumen, albumose, casein and the substitution
products of gelatine and gelatine like bodies without addition of formic aldehyde
are evaporated and then submitted to the action of formic aldehyde and the liquid
absorbed being again evaporated.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performned I declare that what I
claim is
1. The process for rendering insoluble albumen and albumen like matters, casein,
albumose, and the products of conversion of glue and gelatine consisting in
a.) Mixing the solutions of the before named bodies with formic aldehyde and
then evaporating upon suitable backings such as glass, or metal plates, paper
and the like. Or
6.) Submitting the dried layer of the before mentioned bodies without formic
aldehyde to the subsequent action of solutions in water of formic aldehyde or
wet gaseous formic aldehyde and again evaporating the formic aldehyde
absorbed in the layers.
2. The layers, insoluble in water, produced as above described with or without a
backing.

page_text: 3. A process for rendering insoluble albumen and albumen like matters, casein,
albumose and the products of conversion of glue and gelatine substantially as
described.
Die 2nd dox of September 1895
AUGUST ZIMMERMANN.