IMPROVEMENTS IN PHOTOGRAPHIC SURFACES, AND THE COMPOSITIONS AND PROCESS FOR PREPARING THE SAME
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by Victor Moreau Griswold at the
Office of the Commissioners of Patents, with his Petition, on the
11th December 1865.
J, VICTOR MOREAU GRISWOLD, of Peekskill, in the County of West-
chester, State of New York, United States of America, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN PHOTOGRAPHIC
SURFACES, AND THE COMPOSITIONS AND PROCESS FOR PREPARING THE SAME," to be as
follows:-
My Invention consists of an improved photographic surface prepared
and finished in the manner and by means of the compositions herein-after
described, and also in the compositions and process for producing the same,
as herein-after set forth.
The object of thus preparing and finishing a photographic surface is to
reduce expense, simplify the process, and provide a means for taking
photographic pictures on any prepared material by previously coating it
with a perfectly white opaque film ; while at the same time that the expense
is less I am enabled to make a better picture.
In order to carry my Invention into effect I first make a collodion by the
following formula:-

page_text: Gum shellac, bleached
Solution cotton
Castor oil
Glycerine
oz.
-
90 grs..
25 drops.
25 drops.
The proportions and quantities of the above-named substances may be
changed or modified according to the effect desired to be produced, and
for the purpose of rendering the resulting film more or less tough and
pliable or thin and powdery, as well as to affect its sensitiveness to light
and secure either a moist or dry surface. The collodion film must be well
dried before plunging into the silver bath. The acetic ether in the above
solution renders the collodion film powdery by opening the tissue or fibre,
the castor oil renders it tough and prevents" bronzing "in printing, and the
glycerine makes it moist or renders it capable of retaining moisture. The
solution may be used and moderately good results obtained without either
the acetic ether, castor oil, or glycerine, and other resinous gums may be
substituted for the gum kowrie and gum shellac named therein, but I
prefer using the formula as given, as better results are thereby obtained
than by any other with which I am acquainted.
I next prepare a sensitising solution as follows:-

page_text: 5
the silver bath the plate should be again thoroughly dried before being
exposed under the negative..
After exposure the plate is immersed in a solution composed as
follows:-
Water
Solution No. 2
4 oz.
30 to 40 drops.
And gently rubbed with a piece of soft sponge or a soft camel's hair brush
to remove all the unreduced silver from the surface before toning and
fixing. The picture should now be washed thoroughly and toned and
O fixed by any of the many toning and fixing processes, and "finished" with
the opal picture enamel herein-after described.
For printing in the camera I vary the above process by using the opal
collodion (Solution No. 1) sensitised by any of the formulas for sensitising
bromo-iodised collodion, and I then use the ordinary nitrate of silver bath.
5: When the plain silver bath is used with ammonia fuming I produce the
vapour of ammonia as follows:-
Lime unslacked
Ammonia alum
1 part.
I part.
The lime and alum pulverised separately and then triturated together and
placed in the fuming box. By the use of this mixture I obtain strong
ammonia fumes at a cost very much below that of any other process now
known to the trade.
The plate is exposed wet in the copying camera and developed in the
usual manner; if desired it may be toned with chloride of gold and after-
wards fixed with cyanide of potassium or hyposulphite of soda.
This last process converts the picture into a negative, and it is recon-
verted into a positive by the application of the following :—
Water
. 3 oz.
DOLUTION
Bleached gum shellac
Borax
Water
Linseed oil -
Sulphuric acid
. Albumen
POPA
UKE ENAMEL.
-
2 lbs.
-
6 oz.
-
1 gall.
- 2 oz.
1 dram.
1 oz.

page_text: The borax should be dissolved in the water over a fire and when
dissolved the sulphuric acid well stirred in. Next the oil should be added
and the solution brought rapidly to the boiling point, after which the
shellac should be added, the mixture being stirred continually until the
shellac is dissolved, when it should be allowed to become cool, then add
the albumen previously thoroughly beaten up with about a pint of the
"enamel." When settled, unless it is designed to be used upon wet films,
add about one-third of its bulk of alcohol to make it flow readily over the
plate. Let the enamel dry "spontaneously" in a moderately warm place.
In the above solution (No. 3) the linseed oil is used to render the enamel
tough and pliable, the sulphuric acid to harden it, and the albumen to
clarify it and give additional lustre. The enamel may be made and used
very well without the three ingredients above named, but I prefer using
them as a better result is obtained thereby.
The above-described manners of producing the opal collodion, sensi-
tising solution, and opal picture enamel, while apparently distinct in them-
selves are each very important in the obtaining of the desired object, which
is the production of a more perfect photographic picture upon an opal
surface in a comparatively cheap and easy manner. By the above process
and compositions I am enabled to form a perfectly white opaque collodion
film, sensitised by a process which gives increased rapidity to the action of
the light, and also preserves the purity of the white film as well as the film
itself, and finished with an enamel which is peculiarly adapted to this
purpose, and the only one I have been able to discover which will not
render the white film transparent and ruin the picture.
I am also enabled to print photographic pictures upon japanned iron or
other japanned surfaces of any colour or upon glass, superseding the
present difficult and expensive opal glass process; or upon cardboard, or
other paper or paper-like surface previously prepared for the purpose, or
any other smooth surface, thus doing away with much of the present tedious
and expensive manipulations in printing photographs or opal pictures.