AN IMPROVED METHOD OF MAKING PAPER TRANSPARENT TO RENDER IT SUITABLE AS A SUBSTITUTE FOR GLASS FOR PHOTOGRAPHIC AND OTHER PURPOSES
Year: 1885

page_text: 66
We, WALTER BENTLEY WOODBURY, of South Norwood in the County of Surrey,
Photographer, and FELIX VERGARA, of Lordship Lane in the County of Surrey,
Gentleman do hereby declare the nature of our invention for AN IMPROVED
METHOD OF MAKING PAPER TRANSPARENT TO RENDER IT SUITABLE AS A SUBSTITUTE
FOR GLASS FOR PHOTOGRAPHIC AND OTHER PURPOSES" to be as follows:-
This invention consists in methods of rendering paper transparent enough to
take the place of glass in the various wellknown photographic processes, as well
as for other purposes, its use in photography being to reduce or avoid the great
weight which it is necessary to carry where glass plates are used, as at present.
To carry out the invention, we use a thin even textured paper, which we render
transparent by immersing it for several days in a solution consisting of Benzole or
Benzoline in which has been dissolved a sufficient quantity of Gum, Dammar
Mastic or other suitable gum, to which is added in suitable proportion an elastic
gum such as Gum Elemi. Thus or India Rubber in solution, in order to obtain the
required pliability in the paper which is to be rendered transparent and used as a
substitute for glass. Or we use the same solutions to render transparent, paper on
which a photographic negative or positive has already been made.
Where this paper prepared as described is to be used as a substitute for glass in
photography, it is coated when dry in the ordinary way with emulsion of the well
known kind.
Dated this 11th day of August 1885
EDWARDS & Co,
Agents for the Applicants.

page_text: An Improved Method of Making Paper Transparent to Render
it Suitable as a Substitute for Glass for Photographic and
other Purposes.
We, WALTER BENTLEY WOODBURY, of South Norwood, in the County of Surrey,
Photographer, and Felix VERGARA, of Lordship Lane, in the County of Surrey,
Gentleman, 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 (that is to say) :-
This invention relates to improved methods of rendering paper transparent
enough to be used as a substitute for glass in the various wellknown photographic
processes, as well as for other purposes, its advantage when used in photography
being in the reduction or avoidance of the great weight which it is necessary to
carry when glass plates are used as at present, and the excellence of the results.
obtained by its use.
In order to carry out our invention, we use a thin even textured paper, which
we render transparent by immersing it for a sufficient time, which may be for
several days in a solution consisting of Benzole or Benzoline in which has been
dissolved a sufficient quantity of gum dammar, mastic, or other gum of the like
nature, to which is added a suitable proportion of an elastic gum such as gum
elemi, or india rubber, in solution, in order to obtain the required flexibility of the
paper which is to be rendered transparent and used as a substitute for glass. The
sheets of paper after having been soaked as described in the solution are removed.
and dried, and are then transparent enough to be used as a substitute for glass
whilst retaining sufficient flexibility.
"
Where they are to be used as supports for photographic negatives, they are
immersed in a weak solution of gelatine to form a suitable surface to receive
emulsion, and when dry are treated with emulsion or otherwise coated and the
picture obtained upon them in the usual way by light. Or the solution prepared
as described above may be used to render transparent, paper upon which photo-
graphic negatives or positives have already been produced.
The gums used and their proportions may be varied more or less without
injuriously affecting the result, but the following is a formula, which may advan-
tageously be used.
Rasala
20
3:- -11 about

page_text: and let them dry.
The sheets of paper rendered transparent in the way described can then be used
for coating with emulsion, or for other purposes such as making tracings or
drawings.
When used as a substitute for glass for photographic negatives, paper rendered
transparent by the improved method described is exceedingly easy to manipulate,
and the results obtainable upon it are equal to the finest glass negatives. They
require no treatment with substances such as castor oil or vaseline, and can be used
to print from in the sun without becoming "tacky," whilst there is no risk from
breakage nor trouble in the storage of negatives. They are of very little weight,
and print as quickly as glass negatives, dust does not adhere to their surface as to
ordinary gelatine negatives, they are easily developed, and can be fixed and washed
in the same manner and as easily as ordinary paper prints.
Having now particularly described and ascertained the nature of our said
Invention, and in what manner the same is to be performed, we declare that what
we claim is :-
1. The process of rendering paper transparent whilst retaining its flexibility, by
treating it in a solution of the gums in benzole, substantially as described.
2. In combination with the method of rendering sheets of paper transparent by
the process described, the method of preparing them to receive emulsion for the
purpose of obtaining photographic negatives, by immersing them in a solution of
gelatine, substantially as described.