IMPROVEMENTS IN ENGRAVING BY PHOTOGRAPHY
Year: 1884

page_text: I LOUIS DE Roux, of Bègles, near Bordeaux, in the Department of the Gironde,
in the Republic of France do hereby declare the nature of my invention for
IMPROVEMENTS IN ENGRAVING BY PHOTOGRAPHY to be as follows:-
The object of my invention is to engrave upon and prepare plates for printing
and other analogous purposes by means of photography.
I take a "negative" by the ordinary means, and from this a "positive." I then
place the positive upon carbon paper which has previously been dipped in a bath
containing water to which four per cent. of bichromate of potash has been added.
The positive and the carbon paper are then placed in a frame and exposed to the
sun for an hour or two, according to its strength. The carbon paper is then laid
upon a copper plate in a trough, the paper being first moistened, and is caused to
adhere to the copper plate by means of a roller. Boiling water is then poured
upon the paper, and after an interval of time, which experience only will indicate,
I remove the paper, and there remains on the copper plate the mass of carbon from
the paper. This is then washed off the plate with hot water, and there remains.
the engraving in relief upon the copper plate. The copper plate is then dried.
I then prepare an alloy (which I name "Coclator") composed of the following
ingredients melted together viz-
This alloy, in a state of fusion, is placed in a special trough, and upon the alloy
I place the copper plate with the engraved side upon and next to the alloy. The
whole is then placed under a press, and, with the necessary pressure applied thereto,
is allowed to get cool. When the alloy is cold, and withdrawn from the press,
I remove the copper plate carefully, and the alloy bears the facsimile of the object
to be reproduced.
After removing the superfluous metal the plate may be used as a stereopype
plate, from which prints may be taken as in ordinary letterpress printing, or as in
copper or steel plate printing, or as in printing from a lithographic stone.
It is obvious that my invention is applicable to the production of bas reliefs, in
metal, and analogous operations.
RICHARD JORDAN,
Agent for Louis de Roux.

page_text: ICATION,
I, LOUIS DE ROUX, of Bègles, near Bordeaux, in the Department of the Gironde,
in the Republic of France, do hereby declare the nature of my invention for
IMPROVEMENTS IN ENGRAVING BY PHOTOGRAPHY and in what manner the same is
to be performed, to be particularly described and ascertained in and by the following
statement:
The object of my invention is to engrave upon and prepare plates for printing
and other analogous purposes by means of Photography.
I take a "Negative" by the ordinary means, and from this a "Positive." I then
place the Positive upon carbon paper which has previously been dipped in a bath
containing water to which four per cent. of bichromate of potash has been added.
The Positive and the carbon paper are then placed in a frame and exposed to the
sun for an hour or two, according to its strength. The carbon paper is then laid
upon a copper plate in a trough, the paper being first moistened, and is caused to
adhere to the copper plate by means of a roller. Boiling water is then poured
upon the paper, and after an interval of time, which experience alone will indicate,
I remove the paper, and there remains on the copper plate the mass of carbon from
the paper. This is then washed off the plate with hot water, and there remains the
engraving in relief upon the copper plate. The copper plate is then dried.
"
I then prepare an alloy (which I name Coelator") composed of the following
ingredients, melted together, viz.—
This alloy, in a state of fusion, is placed in a special trough, and upon the alloy
I place the copper plate, with the engraved side upon and next to the alloy. The
whole is then placed under a press, and, with the necessary pressure applied thereto,
is allowed to get cool. When the alloy is cold, and withdrawn from the press,
I remove the copper plate carefully, and the alloy bears the facsimile of the object
to be reproduced.
After removing the superfluous metal, the plate may be used as a stereotype
plate, from which prints may be taken as in ordinary letterpress printing, or as in
copper or steel plate printing, or as in printing from a lithographic stone.
It is obvious that iny invention is applicable to the production of bas reliefs, in 3
metal, and analogous operations.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The improved manner of engraving upon and preparing plates for printing
and other analogous purposes by the means and appliances substantially as herein-
before described.
2. The use for the purpose. described of the alloy consisting of the ingredients
and proportions substantially as hereinbefore described.
Dated this Sixteenth of December 1884.
RICHARD JORDAN,
Agent for Louis de Roux.