Mixtures or Solutions for Fixing the Latent Images on Photographic Improvements in Developing or Plates or Sheets.
Year: 1889

page_text: Date of Application, 27th Aug., 1889
Complete Specification Left, 1st Oct., 1889-Accepted, 9th Nov., 1889
PROVISIONAL SPECIFICATION.
to
Mixtures or Solutions for
Fixing the Latent Images on Photographic
Improvements in
Developing or
Plates or Sheets.
relating
or
A communication from abroad by CHARLES SPIRO, of the City, County, & State of
New York, in the United States of America, Gentleman.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E. of the Agency for Foreign
Patent Solicitors, 6 Lord Street Liverpool & 6 Bank Street Manchester, both in
the County of Lancaster, & 323 High Holborn, in the County of Middlesex, Civil
Engineer, do hereby declare the nature of this invention to be as follows:--
This invention relates partly to means for developing the latent images of photo-
graphic plates or sheets without a dark room, and has partly for its object to provide
a developing mixture whereby a complete isolation of actinic rays of light from the
developing photographic plate or sheet will be secured, while a clear view of the
developing image may be obtained.
In developing a photographic plate or sheet in a dark room, as heretofore, in which
the only light was the dian light admitted through ruby or orange colored glass used
to exclude the actinic rays, it was possible for the operator to watch the progress of,
and control, the development only by removing the plate or sheet from the developing
bath from time to time and holding it up to the light for inspection, which process
was wearisome and, in many instances, destructive to the plate, owing to the
incomplete exclusion of the actinic rays and the, perhaps, extreme sensitiveness of
the plate.
To avoid these inconveniences and attain the objects of the invention, a mixture is
provided consisting of any of the ordinary and well known developers, such as
pyrogallic acid and soda, or hydroquinnone, in combination with a non-actinic
inorganic colouring matter, preferably orange aniline, or a mixture of the same and
carmine aniline, where the plate or sheet to be developed is very sensitive.
In preparing this non-actinic developing mixture, at present, the inventor takes,
preferably, hydroquinnone for the developer, and to one pint thereof adds a solution
composed of equal parts of alcohol and water (to energise the solution) to make one
ounce, and two parts of orange aniline and one part of carmine to make half an
ounce, thoroughly mixed so as to form a completely saturated and dark orange
coloured solution of diluted alcohol.
This solution is first well strained to remove all extraneous matter and then
combined with the developer, as before stated.
This mixture is poured into a developing tray, and the photographic plate or sheet
to be developed, transferred from the plate holder into the non-actinic bath thus
prepared, either in the dark room, afterwards admitting the light thereinto or removing
the bath with the contained plate into the light, or by any well known or approved
means for effecting this transfer in the light without exposing the plate or sheet
thereto.
The non-actinic bath will completely exclude the actinic rays from the immersed
plate or sheet, and, the developing mixture being perfectly clear, the development
will proceed in full view of the operator, who may thus easily note the progress of
the development.
When the image is found to be fully developed, the plate or sheet may be transferred
in the light to a bath of any of the usual fixing agents, such as hyposulphite of soda,
and the bath quickly covered with a dark cloth; or the fixing bath may be likewise
rendered non-actinic by the addition thereto of the same non-actinic colouring
matter.

page_text: The transfer of the developed plate or sheet from the non-actinic developing bath
into the fixing bath in the light may be thus effected without clouding the image,
insomuch as the aniline colouring matter, as well as all other inorganic colouring
matters so far as known, form a perfect solution and fill the pores of the gelatine
film, so as to form a perfectly non-actinic envelope over the film, lasting until the
plate is immersed in the fixing bath. The fixing action then immediately commencing,
light has no further effect on the film.
The proportions of the developer and coloured solution above given will yield a
safe and efficient developer, if the tray is no larger than necessary to be half filled
by the mixture. But the circumstances of the case and the experience of the operator
will determine the depth of colour in the mixture.
The right is hereby reserved to make future application for the non-actinic fixing
mixture hereinbefore referred to.
Dated the DCAL
A 1000
WM. P. THOMPSON & Co.,
Agents for the Applicant.
Improvements in
COMPLETE SPECIFICATION.
for
or relating to Mixtures or Solutions
Developing or Fixing the Latent Images on Photographic
Plates or Sheets.
A communication from abroad by CHARLES SPIRO, of the City, County, and State
of New York, in the United States of America, Gentleman.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E. of the Agency for Foreign
Patent Solicitors 6 Lord Street, Liverpool and 6 Bank Street Manchester both in
the County of Lancaster and 323 High Holborn in the County of Middlesex, Civil
Engineer, 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 :-
This invention relates partly to means for developing the latent images of photo-
graphic plates or sheets without a dark room, and has partly for its object to provide
a developing mixture whereby a complete isolation of actinic rays of light from the
developing photographic plate or sheet will be secured, while a clear view of the
developing image may be obtained.
In developing a photographic plate or sheet in a dark room, as heretofore, in which
the only light was the dim light admitted through ruby or orange coloured glass
used to exclude the actinic rays, it was possible for the operator to watch the progress
of, and control, the development only by removing the plate or sheet from the
developing bath from time to time and holding it up to the light for inspection, which
process was wearisome and, in many instances, destructive to the plate, owing to the
incomplete exclusion of the actinic rays and the, perhaps, extreme sensitiveness of the
plate.
To avoid these inconveniences and attain the objects of the invention, a mixture is
provided consisting of any of the ordinary and well known developers, such as
pyrogallic acid and soda, or hydroquinone, in combination with a non-actinic
transparent colouring matter, preferably orange aniline, or a mixture of the same
and carmine aniline, where the plate or sheet to be developed is very sensitive.
In preparing this non-actinic developing mixture, at present, the inventor takes,
preferably, hydroquinone for the developer, and to one pint thereof adds a solution
composed of equal parts of alcohol and water (to energise the solution) to make one
ounce, and two parts of orange aniline and one part of carmine to make half an ounce,
thoroughly mixed so as to form a completely saturated and dark orange coloured
solution of diluted alcohol.
This solution is first well strained to remove all extraneous matter and then
combined with the developer, as before stated.
This mixture is poured into a developing tray, and the photographic plate or sheet

page_text: to be developed transferred from the plate holder into the non-actinic bath thus
prepared, either in the dark room, afterwards admitting the light thereinto, or
removing the bath with the contained plate into the light, or by any well known or
approved means for effecting this transfer in the light without exposing the plate
or sheet thereto.
The non-actinic bath will completely exclude the actinic rays from the immersed
plate or sheet, and, the developing mixture being perfectly clear, the development
will proceed in full view of the operator, who may thus easily note the progress of
the development.
When the image is found to be fully developed, the plate or sheet may be trans-
ferred in the light to a bath of any of the usual fixing agents, such as hyposulphite
of soda, and the bath quickly covered with a dark cloth; or the fixing bath may be
likewise rendered non-actinic by the addition thereto of the same non-actinic colouring
matter.
The transfer of the developed plate or sheet from the non-actinic developing bath
into the fixing bath in the light may be thus effected without clouding the image,
insomuch as the aniline colouring matter forms a perfect solution and fills the pores
of the gelatine film, so as to form a perfectly non-actinic envelope over the film,
lasting until the plate is immersed in the fixing bath. The fixing action then
immediately commencing, light has no further effect on the film.
The proportions of the developer and coloured solution above given will yield a
safe and efficient developer, if the tray is no larger than necessary to be half filled by
the mixture. But the circumstances of the case and the experience of the operator
will determine the depth of colour in the mixture.
The right is hereby reserved to make future application for the non-actinic fixing
mixture hereinbefore referred to.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is :-
1. The combination, with a photographic developer, of a non-actinic transparent
colouring matter, substantially as and for the purpose specified.
2. The combination, with a photographic developer, of a non-actinic solution of
aniline colouring matter, substantially as and for the purpose specified.
3. The combination, with a photographic developer, of orange aniline, substantially
as and for the purpose specified.
Dated this 30th day of September 1889.
WM. P. THOMPSON & CO.,
Agents for the Applicant.