IMPROVEMENTS IN THE TREATMENT OF PAPER FOR PHOTOGRAPHIC PURPOSES
Year: 1881

page_text: LETTERS PATENT to Herbert John Haddan, of the Firm of Herbert and
Company, Solicitors of Patents, of 67, Strand, in the City of Westminster,
Civil Engineer, for an Invention of "IMPROVEMENTS IN THE TREATMENT OF
PAPER FOR PHOTOGRAPHIC PURPOSES." A communication from abroad by
Jean Joseph Désiré Hutinet and Pierre Ernest Lamy, both of Paris, in the
Republic of France.
PROVISIONAL SPECIFICATION left by the said Herbert John Haddan at the
Office of the Commissioners of Patents on the 8th April 1881.
"
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors of
Patents, of 67, Strand, in the City of Westminster, Civil Engineer. 'IMPROVEMENTS
IN THE TREATMENT OF PAPER FOR PHOTOGRAPHIC PURPOSES." A communication
from abroad by Jean Joseph Désiré Hutinet and Pierre Ernest Lamy, both of Paris,
in the Republic of France.
This Invention relates to a process of preparing photographic paper by means of
gelatine or any other suitable gummy or albuminous substance, insoluble, or
rendered insoluble, in cold water, and containing argentic bromide or any other
precipitate of silver which is insoluble in water; this photographic paper produces
by itself, after having been exposed to natural or artificial light under a negative,
and by development, positive copies as brilliant as, and, if desired, more brilliant
than those which are obtained by means of argentic chloride on paper which has
been once or twice albumenized. Paper which has been coated with gelatine
mixed with an argentic chloride, jodide, or bromide, gives, after its exposure to
natural or artificial light under a negative, and subsequent alkaline development or
development by ferric oxalate or pyrogallic acid, dull, indistinct, and disagreeable
copies. In order to render these images acceptable it is necessary to encausticate,
albumenize, collodionise, or varnish them.
To avoid this grave inconvenience, which complicates the work and reduces the
application and therefore also the sale of this paper (simply coated with gelatino-
bromide of silver), the inventors have been seeking and have found means of

page_text: preparing this paper in such a manner that it produces at once and by itself images
as brilliant as, or more brilliant than, those which have hitherto been produced by
means of argentic chloride on paper once or twice albumenized.
According to the present Invention this result is obtained in various ways, as
follows: 1st Method. The paper is first, that is to say, before coating it with the
gelatino-bromide of silver (argentic bromide is preferred, the great sensitiveness of
which has been long known), coated with gelatine (or any other suitable gummy
or albuminous permeable or impermeable substance) containing permanent white.
or any other suitable white coloring matter, wax, soap, or a solution of white
gumlack; subsequently the paper is dried, calendered, and polished by means of a
brush or by a pad with or without tale. This paper is then coated with a sensitive
film containing gelatine and argentic bromide, in a manner similar to the treatment
of other photographic paper.
Second Method. The paper is first coated with a solution of resin or resinous
gum in alcohol or in any suitable essence, or in alkaline or saline water, after which
it is calendered when necessary.
Subsequently the paper is covered with the sensitive film of gelatino-bromide
of silver.
Third Method. The paper is first collodionized, after which it may or may not
be calendered, and lastly the sensitive coating of gelatino-bromide of silver is
applied.
Fourth Method. The paper is first coated with gelatino-bromide of silver,
subsequently dried and coated with a solution of white resin or resinous gum in
alcohol or in any suitable essence, or in alkaline or saline water, which coating may
be applied either by passing the paper through a bath or by means of rollers. The
brilliant coating thus obtained is hard and insoluble in water.
Fifth Method. To the surface of the paper only is applied a sensitive emulsion
containing gelatine and argentic bromide, and which has been mixed with a suitable
quantity of a solution of resin or resinous gum in alcohol or in an essence, or in
alkaline or saline water.
Sixth Method. Into the emulsion is introduced a resin or a resinous gum
dissolved in a suitable solvent, and one side of the paper is covered with it; after
this first coating has become dry, the paper is coated with a simple solution of
resin or resinous gum. On paper thus prepared the brilliant surface of the image
is hard and insoluble.
To prevent the paper, which has been prepared by one of the methods described,
from being brittle or liable to crease, into the ingredients used is introduced a
suitable quantity of glycerine or sugar, or into the resinous coating a suitable
resinous substance having a similar effect.
Whichever of the described methods is used for preparing the paper, the image
produced by exposure develops itself regularly, either on the upper surface (that
which has been coated once or more) or on the lower surface, or on both surfaces
together, and after development, washing, and drying, an image is left which may
be more or less brilliant according to the method applied and the quantity of resin
contained in the solution.

page_text: SPECIFICATION_in pursuance of the conditions of the Letters Patent filed
by the said Herbert John Haddan in the Great. Seal Patent Office on the
7th October 1881.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors of
Patents, of 67, Strand, in the City of Westminster, Civil Engineer. "IMPROVEMENTS
IN THE TREATMENT OF PAPER FOR PHOTOGRAPHIC PURPOSES." A communication
from abroad by Jean Joseph Désiré Hutinet and Pierre Ernest Lamy, both of Paris,
in the Republic of France.
This Invention relates to a process of preparing photographic paper by means of
gelatine or any other gummy or albuminous substance, insoluble, or rendered
insoluble, in cold water, and containing argentic bromide or any other precipitate
of silver which is insoluble in water; this photographic paper produces by itself,
after having been exposed to natural or artificial light under a negative, and by
development, positive copies as brilliant as, and, if necessary, more brilliant than
those which are obtained by means of argentic chloride on paper which has been
once or twice albumenized.
Paper which has been coated with gelatine mixed with an emulsion of an
argentic chloride, jodide, or bromide, gives to natural or artificial light by its
exposure under a negative, and subsequent alcaline development or development
by ferric oxalate or pyrogallic acid, dull, indistinct, and disagreeable copies. In
order to render these images acceptable it is necessary to encausticate, albumenise,
collodionise, or varnish them.
To avoid this grave inconvenience, which complicates the work and reduces the
application and therefore also the sale of this paper (simply coated with gelatino-
bromide of silver), the inventors have been seeking and have found means of
preparing this paper in such a manner that it produces at once and by itself images
as brilliant as, or more brilliant than, those which have hitherto been produced by
means of argentic chloride on paper once or twice albumenized.
I obtain this result in various ways:-
-
First Method. The paper is first, that is to say, before applying the gelatino
bromide of silver coating (I prefer argentic bromide, the great sensitiveness of
which has been long known), coated with gelatine or any other suitable gummy or
albuminous permeable or impermeable substance containing any suitable white
coloring matter, for instance, baric sulphate; further, wax, soap, or a solution of
white gum lack; subsequently the paper is dried, calendered, and polished by
means of a brush or by a point ball with or without talc. This paper is then
coated with a sensitive film containing gelatine and argentic bromide in a manner
similar to the treatment of other photographic paper.
Second Method. The paper is first coated with a solution of resin or resinous
gum in alcohol or any other suitable essence, or in alcaline or saline water, after
which it is calendered when necessary; subsequently I cover the paper with the
sensitive gelatino-bromide of silver coating.
Third Method. I collodionise the paper first, after which it may or may not
be calendered, and lastly I apply the sensitive coating of gelatino-bromide of
silver,
Fourth Method. The paper is first coated with gelatino-bromide of silver,
subsequently dried and coated with a solution of white resin or gum lack in
alcohol or other essence, or in alcaline or saline water, which coating may be
applied either by passing the paper through a basin or by means of rollers. The
brilliant coating thus obtained is hard and insoluble in water.
Fifth Method. I apply to the surface of the paper only with a sensitive emulsion
containing gelatine and argentic bromide, and which has been mixed with a suitable

page_text: quantity of a solution of resin or resinous gum in alcohol, an essence, or alkaline or
saline water.
Sixth Method. I introduce into the emulsion a resin or a resinous gum dissolved
in a suitable solvent, and cover with it one side of the paper; after this first
coating has become dry, I coat the paper with a simple solution of resin or resinous
gum. On paper thus prepared the brilliant surface of the image is hard and
insoluble.
Seventh Method. First the paper is covered with an emulsion of gelatine mixed
with bromide of silver or any other precipitate of silver, then it is dried and
another cover applied consisting of a gelatinous or gummy or albuminous solution
in order to produce brilliancy. This solution is watery and contains either alumn,
or potash, or ammonia, or chrome, or a mixture of these salts, or any other product
fit for making the paper insoluble after it has hardened and dried. Alcohol, ether,
acetone, or any other essential liquid may be added without any prejudice.
To prevent the paper, which has been prepared by one of the methods described,
from being brittle or liable to crease, I introduce into the ingredients used a
suitable quantity of glycerine or sugar, or into the resinous coating a suitable
resinous substance having a similar effect. Whichever of the described methods is
used for preparing the paper, the image which has received the impression develops
itself regularly, either through the upper surface (that which has been coated once
or more) or through the lower surface, or through both surfaces together, and after
developinent, washing, turning, washing, and drying, an image is left which may
be moderately or strongly brilliant. The degree of brilliancy depending of the
method applied, and of the quantity of resin incorporated with the solution which
has been used.
CLAIMS.
First The application to the gelatino-bromide coating of the paper of a second
CLAIMS.
First The application to the gelatino-bromide coating of the paper of a second
coating consisting of a varnish or solution of gelatinous, gummy, albuminous, or
similar substances, being insoluble or made insoluble.
Second. The various details of the process, as described in this Specification, for
obtaining the incorporation of the varnish into the gelatino-bromide coating, and
especially the method of covering the gelatino-bromide coating with pure or non-
bromide gelatine, which is made insoluble.
In witness whereof, I, the said Herbert John Haddan, have hereunto set my
hand and seal, this Seventh day of October, A.D. 1881.
H. J. HADDAN. (L.S.)