IMPROVEMENTS IN PRINTING OR PRODUCING COPIES FROM TRACINGS OR DRAWINGS."
Year: 1880

page_text: LETTERS PATENT to Albert Jules Theodore Wild, of Nunhead, in the County.
of Surrey, for an Invention of "IMPROVEMENTS IN PRINTING OR PRODUCING
COPIES FROM TRACINGS OR DRAWINGS."
PROVISIONAL SPECIFICATION left by the said Albert Jules Theodore
Wild at the Office of the Commissioners of Patents on the 2nd December
1880.
ALBERT JULES THEODORE WILD, of Nunhead, in the County of Surrey.
"IMPROVEMENTS IN PRINTING OR PRODUCING COPIES FROM TRACINGS.OR
DRAWINGS."
This Invention has for its object the economic and expeditious production of
copies from tracings or drawings.
This Invention consists in dissolving in water chromate of potassa, and when
this is thoroughly effected I add thereto sulphuric acid. The proportions in which
I prefer to use these ingredients are as follows (though I find it convenient to vary
them to suit the nature of the paper or material upon which the subject is to be
reproduced). I take of water one hundred ounces, of chromate of potassa ten
ounces, and when the chromate of potassa is thorough dissolved I add thereto of
sulphuric acid twenty ounces.
sponge over or otherwise apply this solution to the paper or other material or
surface upon which the copy or reproduction is to be made.
When dry place the paper or surface upon which the copy is to be produced
within a suitably constructed frame.
The original is then superimposed thereon within the said frame and exposed to
the action of light, either natural or any light capable of acting upon the sensitive
surface produced by the chemicals herein before mentioned.
The time of the exposure to the light is determined partly by the strength of the
light and partly by the depth or colour of the subject to be reproduced.
When it is found that the exposure has resulted in reproducing the subject the
paper or other surface is placed within a vaporizing box or chamber containing
aniline oil, either pure or with a certain quantity of ammonia, and when it is
removed therefrom it is passed through a bath of pure water and then dried. I
then take the reproduction and sponge it with natron or with unslacked lime for
the purpose of fixing the copy produced. It is then finally dried and pressed by
any suitable means.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Albert Jules Theodore Wild in the Great Seal Patent Office on
the 16th May 1881.
ALBERT JULES THEODORE WILD, of Nunhead, in the County of Surrey.
"IMPROVEMENTS IN PRINTING OR PRODUCING COPIES OF TRACING OR
DRAWINGS."
This Invention has for its object the economic and expeditious production of copies
from tracings, drawings, and objects.
This Invention consists in dissolving in water chromate of potassa, and when
this is thoroughly effected I add thereto sulphuric acid. The proportions in which
I prefer to use these ingredients are as follows, though I may find it convenient to
vary them to suit the nature of the paper or material upon which the subject is to
be reproduced.
I take of water one hundred ounces, of chromate of potassa ten ounces, and
when the chromate of potassa is thoroughly dissolved I add thereto sulphuric acid
twenty ounces.
I sponge over or otherwise apply this solution to the paper or other material or
surface upon which the copy or reproduction is to be made.
When dry I place the paper or surface upon which the copy is to be produced
within a suitably constructed frame.
The original is then superimposed thereon, or in face of the said frame, and
exposed to the action of light, either natural or any light capable of acting upon
the sensitive surface produced by the chemicals herein before mentioned.
The time of the exposure to the light is determined partly by the strength of
the light and partly by the depth or colour of the subject to be reproduced.
When it is found that the exposure has resulted in reproducing the subject, the
paper or other surface is placed within a vapourising box or chamber containing
aniline oil, either pure or with a certain quantity of ammonia, and when it is
removed therefrom it is passed through a bath of pure water, then dried. I then
take the reproduction and sponge it with natron or unslacked lime, or other alkaline
solution, for the purpose of fixing the copy produced. It is then finally dried and
pressed by any suitable means.
And
It will be seen that this Invention consists in the preparation and application of
chemical solutions sensitive to light, and it is for the composition of such solutions
and their application to reproductions that this Invention is claimed.
although it is especially adapted to the reproduction of drawings and tracings it is
also claimed for other similar purposes, as, for instance, copying transparent objects
or objects by reflection, and all other uses of the same solution for photographic
purposes.
In witness whereof, I, the said Albert Jules Theodore Wild, have hereunto
set my hand and seal, this
day of May in the year of our Lord
One thousand eight hundred and eighty one.