Gelatine Plates, Films, or Tissues for Use in Photography, and Process of Manufacturing and Using the same.UFACTURING ANDSING
Year: 1884

page_text: Gelatine Plates, Films, or Tissues for Use in Photography, and
Process of Manufacturing and Using the same.
[Communicated from abroad by George Eastman and William Hall Walker, both
of Rochester, Monroe, New York, United States of America, Manufacturers.]
FILMS OR TISSUES FOR USE
IN PHOTOGRAPHY
I ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex
Engineer do hereby declare the nature of the said invention for "GELATINE PLATES
AND PROCESS OF MANUFACTURING
AND USING THE SAME" (a communication from George Eastman and William Hall
Walker, both of Rochester, Monroe New York United States of America Maṇu-
facturers) to be as follows:-
This invention relates to improvements in the art of photography having for
their object the production of sentized films capable of use in making negatives
and positives in place of the sheets of glass coated with sensitive: emulsions now in
common use and known.in the art as dry plates."
"
The invention consists in the new article of manufacture, the improved film
hereinafter described; in the process or- mode of manufacture of said. film and in-
the improved. process of producing photographic images by the use of said films,
as hereinafter described and claimed.
.
In proceeding to manufacture the films in their preferred form to a suitable paper
or other fabric:is applied a coating of a solution of gelatine dissolved in water of a
strength of about fifty grains to the ounce and allow the same to dry thereon either.
spontaneously or under the influence of artificial heat. It is preferable to use Rives.
paper, such as is commonly albumenized for the manufacture of silver 'prints, on.
account of its freedom.from chemical impurities, fine even grain, and translucency,"
which permits the close examination of the image during development but any
other suitable paper may be employed.
The operation of coating the paper with the gelatine solution may be performed
by floating by means of a brush or dabber, or by suitable machinery, care being
exercised in every case to exclude dust.
When the paper coated with the gelatine as above has become dry it is passed.
between calendering rolls or subjected to the action of any known or appropriate
mechanism which will have: the effect of burnishing, or polishing its surface and
hardening or condensing the body of the paper. This calendering or burnishing.
operation is not a necessary step, but its use is strongly recommended since the
application of the gelatine solution has the effect of raising the grain of the paper
and rendering the same rough and uneven.
The gelatinous paper is next coated with a layer of any ordinary gelatino-argentic
emulsion, the gelatine of which has been rendered more or less insoluble relative to
the primary layer by any appropriate means. The requisite degree of insolubility,
i

page_text: with respect to the first layer or substratum may be obtained by adding to the
finished emulsion when ready for application a suitable quantity of any substance
which possesses the property of rendering the gelatine insoluble when dried, and
which will not cause any chemical decomposition of the emulsion. Chrome alum
answers this purpose effectually and may be employed in quantities varying with
the character of the particular gelatine employed in the emulsion, the season of the
year, or other circumstances, as the judgment of the operator may indicate. The
proportion may be stated generally as approximating five ounces of a solution of
chrome alum (of ten grains to the ounce of water) to one gallon of the finished
emulsion.
The preparation of the sensitive gelatine emulsion is now so well understood in
the art that a particular description thereof is unnecessary. The operation of
coating the gelatinous paper with the sensitive emulsion may he performed in any
preferred way in a sufficiently non actinic light and after the coating of this sheet
has been dried the film is ready for exposure either in the camera or under a
negative according as the operator may desire to produce a positive or negative
image.
During the exposure in the camera it is recommended that the film be temporarily
fixed to some rigid support.
After the exposure of the film its development may be carried out in any
appropriate manner, although we recommend either the well known ferrous-oxalate
development, or the so-called sulphite of soda development, in which the sulphite
of soda, carbonate of soda and pyrogallic acid are employed. The fixing of the
image may be accomplished in a solution of hyposulphite of soda, as usual,
being thoroughly washed, the film may be detached from the paper in the following
or in any equivalent manner :-
After
The fixed and washed film is floated face downward in water and a glass plate
introduced thereunder and lifted out of the water so that the film being lifted with
it may be caused to adhere closely to its surface by a pressure on the back of the
paper.
The adhesion of the film is preferably secured by the sliding pressure of the
edge of a straight piece of rubber or other flexible substance carried along the
paper.
The application of the pressure may be repeated until contact is secured at all
points by the entire displacement of the water and air from between the glass and
the film.
The paper support is next detached from the film, by the application of a suitable
degree of heat to the glass plate, the effect of the heat being to soften the gelatine
layer or substratum between the paper and the insoluble gelatine film containing
the image, so that the paper may be readily stripped off or removed, leaving the
image adhering to the glass.
i
The heat may be applied uniformly by placing the glass on a hot plate of metal
or on a water bath, or by the application of warm water. In case the film has
dried on the glass it must be moistened in water before the application of heat.
This latter being the method preferred. Any remaining traces of the soluble
gelatine may be sponged or washed off with warm water. The glass with the
adhering film thereon will be ready for use on becoming dried. If desired the film
may be varnished as usual.
A thin coating of wax on the glass or other support will admit of the film being
readily stripped therefrom so that it may be printed from either side used or
preserved indefinitely.
Thus the glass having been coated with bees wax dissolved in turpentine
subsequently the gelatine image may be removed therefrom by applying a moist
gelatine sheet to the image and allowing it to dry thereon, after which the two
sheets may be removed together. The operation may be performed in a different
way. Thus the paper may be stripped from the film before development, or after
the development and before fixing, or after fixing as preferred.

page_text: It is proposed to use Cox's transparent or Nelson's N° 1, or other soft gelatine
mixed with an equal quantity of hard gelatine for the first coating, and to make
he emulsion of Simeon's or Heinrich's hard gelatine.
"
By the expression "insoluble gelatine film" and "relatively insoluble gelatine
ilm as herein employed is meant a film which will withstand the solvent action
of warm water for a greater time or to a greater degree than the intermediate or
soluble film. In speaking of an insoluble film it is not meant to be confined to a
film which is absolutely insoluble in water; the invention embracing any gelatine
film which is adapted to withstand the solvent action of water in a marked
degree.
While the film prepared as above described will in most cases answer all practical
purposes, it is discovered than when used under peculiar conditions, that there is a
greater or less tendency of the paper or other support to curl or twist in an
objectionable manner during the process of developing and fixing the image.
To avoid difficulty in this regard it is proposed as a further improvement to
apply to the back of the paper or other support a layer of gelatine designed to
counteract the expansive effect of the gelatine on the front. With the exception of
this coating on the back the second form of film may be identical with that before
described.
In preparing this second form of film it is preferable to apply the gelatine to the
rear side of the paper support first and to use for the purpose a gelatine which is
rendered practically or wholly insoluble by the addition of chrome alum or other
suitable chemical, and which is also rendered flexible by the addition of glycerine.
As a suitable formula is recommended gelatine; Simeon's or Heinrich's seven
thousand grains, water, one hundred and ninety ounces, pure glycerine eighteen
ounces, chrome alum sixty grains. To alum should be added last after being
dissolved in a portion of the water. After the application of this coating, the
paper is dried and is then coated on the opposite or face side with a solution of soft,,
gelatine, Nelsons N⚫ 1
seven thousand grains, one hundred and forty ounces of
water, and five ounces of glycerine. The addition of glycerine to either gelatine
coating is not essential, but it is preferred as the films are thereby rendered more
pliable and capable of being easily worked.
The degree of flexibility may be varied by altering the proportion of glycerine
and the backing may be rendered more or less insoluble by increasing or reducing
the proportion of alum or its equivalent.
After the first coating of the face side of the support has been dried, the support,
with the coating on its two surfaces is passed through suitable calendering rolls or
equivalent burnishing or polishing mechanism by which it is compressed and
hardened and the surface brought to a suitable condition for the reception of the
sensitive film.
A coating of sensitive gelatino argentic emulsion, such as herein before described,
is then applied to the gelatine layer or substratum on the face side, the operation
being formed in a non actinic light. The sensitive coating is rendered insoluble by
the action of chrome alum in the manner hereinbefore recited.
The object of rendering the gelatine on the reverse side of the support insoluble
is to prevent it from becoming dissolved when heat is applied for the purpose of
removing the layer containing the image from the support as before described.
A backing of soluble gelatine will prevent the film from curling, but the insoluble
film is recommended not only for the reason above stated but for various reasons
unnecessary to enumerate.
The operations of exposing, developing, fixing, and transferring the film may be
performed in the same manner as with the film first described.
100

page_text: I, ALFRED JULIUS BOULT of 323. High Holborn, in the County of Middlesex,
Engineer do hereby declare the nature of this invention for
"GELATINE PLATES,
FILMS OR TISSUES FOR USE IN PHOTOGRAPHY AND PROCESS OF MANUFACTURING
AND USING THE SAME" (a communication from George Eastman and William
Hall Walker, both of Rochester, New York, United States of America, Manu-
facturers,) and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
This invention relates to improvements in the art of photography having for
their object the production of sensitized films capable of use in making negatives
and positives in place of the sheets of glass coated with sensitive emulsions now in
common use and known in the art as "dry plates."
The invention consists in the new article of manufacture, the improved film
hereinafter described; in the process or mode of manufacture of said film, and in
the improved process of producing photographic images by the use of said films, as
hereinafter described and claimed.
In the accompanying drawings:-Figure 1 represents a cross section of one of
the improved sensitized films on an enlarged scale.
Figure 2 is a like illustration of the filin in another of its forms.
In proceeding to manufacture the films in their preferred form, to a suitable
paper or other fabric is applied a coating of a solution of gelatine dissolved in water
of a strength of about fifty grains to the ounce, and allow the same to dry thereon
either spontaneously or under the influence of artificial heat. It is preferable to
use Rives. paper, such as is commonly albumenized for the manufacture of silver
prints, on account of its freedom from chemical impurities, fine even grain, and
translucency, which permits the close examination of the image during develop-
ment, but any other suitable paper may be employed.
The operation of coating the paper with the gelatine solution may be performed
by floating by meaus of a brush or dabber, or by suitable machinery, care being
exercised in every case to exclude dust.
When the paper coated with the gelatine as above has become dry, it is passed
between calendering rolls, or subjected to the action of any known or appropriate
mechanism which will have the effect of burnishing or polishing its surface and
hardening or condensing the body. of the paper. This calendering or burnishing
operation is not a necessary step, but its use is strongly recommended since the
application of the gelatine solution has the effect of raising the grain of the paper
and rendering the same rough and uneven.
The gelatinous paper is next coated with a layer of any ordinary gelatino-
argentic emulsion, the gelatine of which has been rendered more or less insoluble
relative to the primary layer by any appropriate means. The requisite degree of
insolubility with respect to the first layer or substratum may be obtained by
adding to the finished emulsion when ready for application a suitable quantity of
any substance which possesses the property of rendering the gelatine insoluble

page_text: when dried, and which will not cause any chemical decomposition of the emulsion.
Chrome alum answers this purpose effectually and may be employed in quantities
varying with the character of the particular gelatine employed in the emulsion, the
season of the year, or other circumstances, as the judgment of the operator may
indicate. The proportion may be stated generally as approximating five ounces of
a solution of chronie alum of ten grains to the ounce of water to one gallon of the
finished emulsion.
The preparation of the sensitive gelatine emulsion is now so well understood in
the art that a particular description thereof is unnecessary. The operation of
conting the gelatinous paper with the sensitive emulsion inay be performed in
any preferred way in a sufficiently non actinic light and after the coating of this
sheet has been dried the film is ready for exposure either in the camera or under
a negative according as the operator may desire to produce a positive or a negative
image. During the exposure in the camera it is recommended that the filin be
temporarily fixed to some rigid support.
After the exposure of the film its development may be carried out in any
appropriate manner, although either the well known ferrous-oxalate development,
or the so called sulphite of soda development, in which the sulphite of soda,
carbonate of soda and pyrogallic acid are employed are recommended. The fixing
of the image may be accomplished in a solution of hyposulphite of soda, as usual.
After being thoroughly washed, the film nay be detached from the paper in the
following or in any equivalent manner.
The fixed and washed filin is floated face downward in water and a glass plate
introduced thereunder and lifted out of the water so that the film being lifted with
it may be caused to adhere closely to its surface by a pressure on the back of the
paper.
The adhesion of the film is preferably secured by the sliding pressure of the edge
of a straight piece of rubber or other flexible substance carried along the paper.
The application of the pressure may be repeated until contact is secured at all
points by the entire displacement of the water and air from between the glass and
the film. The paper support is next detached from the film, by the application of a
suitable degree of heat to the glass plate, the effect of the heat being to soften the
gelatine laver or substratum between the paper and the insoluble gelatine filmm
containing the image, so that the paper may be readily stripped off or removed,
leaving the image adhering to the glass. The heat may be applied uniformly by
placing the glass on a hot plate of metal or on a water bath or by the application
of warm water. In case the film has dried on the glass it must be moistened
with water before the application of heat, this latter being the method preferred.
Any remaining traces of the soluble gelatine may be sponged or washed off with
warm water. The glass with the adhering film thereon will be ready for use on
becoming dried. If desired the film may. be varnished as usual.
In Figure 1 of the drawings A represents the paper or other support; B the
soluble gelatine layer and C, the relatively insoluble layer of sensitized gelatine.
A thin coating of wax on the glass or other support will admit of the film being
readily stripped therefrom so that it may be printed from either side and used or
preserved indefinitely.
Thus the glass having been coated with beeswax dissolved in turpentine
subsequently the gelatine image may be removed therefrom by applying a moist
gelatine sheet to the image and allowing it to dry thereon, after which the two
sheets may be removed together. The operation may be performed in a different
way. Thus the paper may be stripped from the film before development, or after
the development and before fixing, or after fixing as preferred.
It is proposed to use Cox's Transparent, or Nelson's N° 1, or other soft gelatine
mixed with an equal quantity of hard gelatine for the first coating, and to make
the emulsion of Simeon's or Heinrich's hard gelatine.
By the expression "insoluble gelatine film," and." relatively insoluble gelatine
film" as herein employed is meant a film which will withstand the solvent action

page_text: of warm water for a greater time or to a greater degree than the intermediate or
soluble film. In speaking of an insoluble film it is not meant to be confined to a
film which is absolutely insoluble in water; the invention embracing any gelatine
film which is adapted to withstand the solvent action of water in a marked degree.
While the filin prepared as above described will in most cases answer all practical
purposes, it is discovered that when used under peculiar conditions, that there is a
greater or less tendency of the paper or other support to curl or twist in an
objectionable manner during the process of developing and fixing the image. To
avoid difficulty in this regard it is proposed as a further improvement to apply to.
the back of the paper or other support a layer of gelatine designed to counteract
the expansive effect of the gelatine on the front. With the exception of this
coating on the back the second form of film may be identical with that before.
described.
'
In preparing this second form of film represented in Figure 2 it is preferable to
apply the gelatine to the rear side of the paper support first and to. use for the
purpose a gelatine which is rendered practically or wholly insoluble by the addition
of chrome alum or other suitable chemical, and which is also rendered flexible by
the addition of glycerine.
A suitable formula is gelatine, Simeon's or Heinrich's seven thousand grains,.
water, one hundred and ninety ounces, pure glycerine eighteen ounces, chrome
alum sixty grains. The alum should be added last after being dissolved in a
portion of the water. After the application of this coating, the paper is dried
and is then coated on the opposite or face side with a solution of soft gelatine,
Nelson's No 1, seven thousand grains, one hundred and forty ounces of water, and
five ounces of glycerine. The addition of glycerine to either gelatine coating is
not essential, but it is preferred as the films are thereby rendered more pliable
and capable of being easily worked.
.The degree of flexibility may be varied by altering the proportion of glycerine,
and the backing may be rendered more or less insoluble by increasing or reducing
the proportion of alum or its equivalent.
After the first coating of the face side of the support has been dried, the support,
with the coating on its two surfaces is passed through suitable calendering rolls or
equivalent burnishing or polishing mechanism by which it is compressed and
hardened and the surface brought to a suitable condition for the reception of the
sensitive film.
A coating of sensitive gelatino argentic emulsion such as herein before described
is then applied to the gelatine layer or substratum on the face side, the operation
being formed in a non-actinic light. The sensitive coating is rendered insoluble
by the action of chrome alum in the manner hereinbefore recited. The object
of rendering the gelatine on the reverse side of the support insoluble is to prevent
it from becoming dissolved when heat is applied for the purpose of removing the
layer containing the image from the support as before described. A backing of
soluble. gelatine will prevent the film from curling, but the insoluble film is
recommended not only for the reason above stated, but for various reasons
unnecessary to enumerate.
The operations of exposing, developing fixing and transferring the film may be
performed in the same manner as with the film first described.
Referring to Figure 2, A represents the paper backing; B, the soluble gelatine
or substratum on the front; C the sensitive film; and D, the insoluble gelatine
film applied to the back of the paper.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondents I declare that what I claim is
1. A sensitive photographic film consisting of a coating of insoluble sensitized
gelatine, a paper or equivalent support, and an interposed soluble coating.

page_text: 2. In a photographic film, the combination of the support A the insoluble
sensitive gelatino argentic emulsion film C and the soluble interposed gelatine
layer B, substantially as described.
3. In a film for photographic purposes, the combination of a backing sheet or
support of paper or like material, the film of sensitized gelatine adapted to with-
stand the solvent action of water, and an interposed film of soluble gelatine.
4. The process of making photographic films, consisting in applying a coating of
soluble gelatine to a suitable support, drying the same, and subsequently applying
a coating of insoluble sensitized gelatine to the soluble coating and drying it
thereon.
5. As an improvement in the art of manufacturing photographic films, the
process consisting in applying to a paper or equivalent support a coating of
soluble gelatine and permitting the same to dry thereon, subsequently subjecting
said coated sheet to a calendering or burnishing action, and finally applying to
the first coating a film of gelatino argentic emulsion and permitting the same to
dry thereon.
6. The film for photographic purposes consisting of the paper or equivalent
support, the film of insoluble gelatine applied to its back, the film of soluble
material applied to its face, and a gelatino argentic film applied to the soluble
film substantially as specified.
7. As an improvement in the art of photography, the process of producing
photographic images consisting in exposing and developing a sensitive gelatino
argentic bromide film affixed to a suitable support by a layer of soluble material
attaching the developed film while upon its support to a rigid plate, and finally
detaching the support from the film by the aid of heat, leaving the image upon the
plate substantially as specified.
8. As an improvement in the art of producing photographic negatives through
which to print upon sensitized surfaces by transmitted light in the usual manner,
the process, consisting in affixing a film of insoluble sensitive argentic gelatine
emulsion firmly to paper or equivalent support, exposing and developing said
film, to produce a permanent image therein, and finally attaching said film face
down to a plate of glass, substantially as described, the paper support being
subsequently removed.
9. As an improvement in the art of photography, the process consisting in first
providing an insoluble sensitive gelatine film fixed by a soluble material to a
supporting sheet, second, exposing and developing said film, third, attaching the
developed film to a rigid plate by means of wax or its equivalent, fourth,
detaching the support from the film, and fifth stripping the film from the waxed
surface.
10. As a new article of manufacture an insoluble sensitive gelatino bromide
film having glycerine incorporated therein, substantially as and for the purpose
described.
11. The herein described photographic film rendered flexible by means of
glycerine and consisting of the support A having a layer of insoluble gelatine
emulsion C attached thereto substantially as described.
12. As a support for the film of sensitive gelatino argentic emulsion a flexible
sheet coated with a layer of soluble gelatine and calendered on the coated surface,
substantially as described.
-