An Improved Method of Photographic Printing in Bromide of Silver.
Year: 1893

page_text: Date of Application, 28th Mar., 1893
Complete Specification Left, 27th Dec., 1893-Accepted, 27th Jan., 1894
PROVISIONAL SPECIFICATION.
An Improved Method of Photographic Printing in Bromide
of Silver.
I, EPHRAIM NORDEN 52 Jerningham Road Hatcham, London, S.E. School-
master do hereby declare the nature of this invention to be as follows:-
(1.) Paper, glass, or other material is spread with a solution of gelatine containing
a soluble bromide and allowed to dry.
(2.) It is then floated upon a solution of nitrate of silver of suitable strength and
again allowed to dry.
(3.) It is then floated upon a solution of oxalate of potassium of suitable strength.
The novelty consists in the application of the oxalate of potassium and principally
in the fact that material so prepared prints right out without requiring to be
chemically developed.
Dated this 27th day of March 1893.
COMPLETE SPECIFICATION.
An Improved Method of Photographic Printing in Bromide
of Silver.
I, EPHRAIM NORDEN 52 Jerningham Road St. Catharine's Park Hatcham, S.E.
School-master 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 :-
My invention relates to the preparation of a printing-out bromide of silver for
photographic purposes, that is to say, of bromide of silver which will yield a com-
pletely printed visible image in the printing frame by the action of light without
after development. I first take from 55 to 110 parts by weight of gelatine and melt it
in 1000 parts by weight of water. I then add, in proportions stated hereafter, a
soluble bromide such as the bromide of ammonium, or barium, or cadmium, or calcium,
or lithium, or sodium, or potassium, or zinc, or any other that will not reduce nitrate
of silver to the metallic state. For every 1000 parts by weight of water I may
take from 25 to 50 parts by weight of bromide of ammonium, or from 37.5 to
75 parts by weight of bromide of barium, or from 45 to 90 parts by weight of
bromide of cadmium, or from 35 to 70 parts by weight of bromide of calcium, or
from 25 to 50 parts by weight of bromide of lithium, or from 25 to 50 parts by
weight of bromide of sodium, or from 27.5 to 55 parts by weight of bromide of
potassium or from 27.5 to 55 parts by weight of bromide of zinc.
I may take one bromide only or I may mix any 2 or more in proportionate
parts. I may also add from 8 to 12 parts by weight of a soluble chloride, such as
chloride of sodium or ammonium and I may further add from 5 to 1 part by
weight of an acid such as hydrochloric acid. I then mix the bromide or bromides
to the hereinbefore mentioned gelatine solution together with the chloride and
hydrochloric acid, and with the mixed solution I coat paper or other suitable
material either by means of a brush or other suitable appliance and allow it to
dry. I then float the material, prepared side down, on a solution of nitrate of
silver containing from 114 to 137 parts by weight of nitrate of silver to 1000 parts
by weight of water, and again allow it to dry. I again float the material, prepared

page_text: side down, on a solution of oxalate of potassium containing from 180 to 200 parts
by weight of oxalate of potassium to 1000 parts by weight of water, and again
allow it to dry. The material prepared in the above mentioned manner is then
ready for printing, after which it may be toned and fixed in the usual way.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is―
The preparation of bromide of silver on paper or other material in such manner
as to yield a completely printed visible image in the printing frame by the action
of light substantially in the manner hereinbefore described.
Dated this 26th day of December 1893.
EPHRAIM NORDEN