Year: 1899

page_text: We, JOHN EDWARD THORNTON, of Rokeby, Oldfield Road, Altrincham, Cheshire,
Manufacturer, and CHARLES FREDERICK SEYMOUR ROTHWELL, of Worsley Mills,
Worsley Street, Hulme, Manchester, Lancashire, Chemist, do hereby declare the
nature of this invention to be as follows:-
This invention relates to the production of direct positive photographs, and
is an improvement upon the invention described in our Patent No. 887 of
January 14th 1899.
In that invention we use a sensitive gelatino-bromide emulsion coated very
thinly upon an opaque black or colored paper base. After exposure the film is
developed, fixed, whitened, washed, and dried, yielding a positive image as seen
by reflected light. This image is reversed as regards right and left, unless a
reversing prism or mirror is used.
This invention enables us to obtain non-reversed positive pictures, by reversing
the image upon or in relation to its support, after the picture has been com-
pleted and dried. In order to carry this out we make the film as a stripping film,
in the following manner.
We take a suitable black, colored, or other opaque paper support, and coat this
with flexoid, the whole being then well calendered. Flexoid is the name given
to a new product forming the subject of an application for a Patent in our joint
names, dated February 25th 1899, and numbered 4237. It renders the paper
base waterproof and serves the important double purpose of causing the film to
adhere to the paper base during all the various operations, and yet enables it to
be readily stripped therefrom when the finished picture has been dried.
We prefer flexoid for the purpose, but a similar, though less satisfactory,
result can be got by preparing the paper base in other ways. For instance, it
may be rendered waterproof by coating with celluloid or other varnish, and to
enable stripping to be easily performed we may treat the paper with a coating
of rubber or collodion.
The film itself is next formed upon the prepared paper base, by coating it with
gelatine, celluloid or other suitable material, and after this is quite dry we coat
it with the sensitive emulsion, which must be very thin and transparent coating.
The complete film is exposed in the camera, developed, fixed, whitened, washed,
and dried, and is then ready for stripping, which is easily performed by merely
pulling the film and paper base apart.
To reverse the picture thus obtained and complete a. non-reversed picture, the
paper backing is thoroughly wetted with water, and then the film is laid upon it,
with the image bearing side in contact with the paper, and the gelatine or cellu-
loid side uppermost, and the two are carefully squeegeed into close optical con-
tact and allowed to dry.
The result is the finished picture. The whole operations present no special

page_text: difficulties and the picture is obtained direct, with the minimum of trouble, and
without the intervention of negative making and print making processes.
Dated this 28th day of August 1800
J. E. THORNTON,
C. F. S. ROTHWELL.
We, JOHN EDWARD THORNTON, of Rokeby, Oldfield Road, Altrincham, in the
County of Chester, Manufacturer, and CHARLES FREDERICK SEYMOUR ROTIIWELL,
of Worsley Mills, Worsley Street, Hulme, Manchester, in the County of Lan-
caster, Chemist, do hereby declare the nature of this invention and in what man-
ner 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 production of direct positive
photographs, (such as described in the Specification of our earlier Patent 887
of 1899).
Hitherto in the production of such direct positive photographs, there has been
used a sensitive gelatino-bromide emulsion coated very thinly upon a base of
opaque black or coloured paper. After exposure, the film is developed, fixed,
whitened, washed and dried, yielding a positive image, as seen by reflected light.
This image is reversed, as regards right and left, unless a reversing prism or
mirror is used.
By this invention, non-reversed or correct positive pictures can be obtained.
It consists essentially of a photographic sensitive film, capable of being stripped
from its base, mounted upon a base of black or coloured paper, from which it
can be readily removed and re-attached to the same, or another black or coloured
paper with the reverse side to the paper, after having been developed, fixed and
whitened.
In carrying out the invention, we take a black, coloured or opaque paper base
and apply or spread over the surface of the same a suitable stripping medium,
and over that the sensitive emulsion.
The stripping medium may be rubber or collodion applied on a waterproof
surface, but we prefer the material formed by dissolving and drying the alumi-
nium or zinc salts of the fatty acids. This preparation renders the black or
coloured paper base waterproof, and serves the important double purpose of
causing the film to adhere to the paper base during all the various operations,
and yet enables it to be readily stripped therefrom. when the finished picture has
been dried.
The paper with the stripping medium may be coated direct with the sensitive
gelatine emulsion in a thin layer, or it may be first coated with a reinforcing
medium such as gelatine, celluloid, or other material to support the image, and
when quite dry the sensitive emulsion be coated thereon in a thin transparent
layer.
The complete film, made in the manner described above, is exposed in the
camera, developed, fixed, whitened, and washed. When the washing is com-
plete a piece of black or coloured paper, previously coated with gelatine, gum,
or other suitable adhesive substance, is pressed into contact with the face of the
picture, and the whole allowed to become quite dry. The picture is completed
by merely pulling the two pieces apart, when the picture attaches itself to the

page_text: adhesive black or coloured paper, and is consequently reversed during this
operation.
:
The film may be first stripped from the black or coloured paper base, and
then the reverse side applied and caused to adhere to the same, or to another
black or coloured paper base.
The result is the finished picture. The whole operations present no special
difficulties, and the picture is obtained direct with the minimum of trouble and
without the intervention of negative making and print making processes.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that what
we claim is: :-
1. A photographic film comprising in its construction a black or coloured
paper base, a stripping medium applied thereto, and a layer of gelatine to sup-
port the image, and sensitive emulsion capable of being removed therefrom,
substantially as described.
2. The method of producing direct camera positives consisting in using a sen-
sitive film mounted on a black or coloured paper backing or support, developing,
fixing and whitening the image or picture, stripping the film, carrying the same
from its base, and attaching the reverse side to the same, or another black or
coloured paper base, substantially as described.
3. The method of producing non-reversed or complete direct camera positives
substantially as described..
Dated this 26th day of March 190n
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents.