Improvements in Reproducing on Paper, Fabrics, or other Materials Facsimiles of Colored Originals.
Year: 1899

page_text: Date of Application, 29th Nov., 1899
Complete Specification Left, 13th Aug., 1900-Accepted, 3rd Nov., 1900
PROVISIONAL SPECIFICATION.
Improvements in Reproducing on Paper, Fabrics, or other Materials
Facsimiles of Colored Originals.
We, THEODORE TRUCHELUT, of No. 34, Quai des Orfèvres, Paris, Chemical
Engineer, and AMÉDÉE AUGUSTE ROCHEREAU, of No. 36, Rue Merlin Thionville,
Suresnes, Department of Seine, Mechanic, both in France, do hereby declare the
nature of this invention to be as follows:-
The invention relates to improvements in reproducing on paper fabrics or other
materials facsimiles of colored originals.
According to the invention the original drawing, painting, or the like is
produced by the artist by means of primary colours which by mixing will yield
the whole chromatic scale of intermediate colours and shades as generally known
in such artistic productions.
The colours employed are formed of substances which from the chemical and
actinic point of view, have such properties that by the treatments to which the
original is subjected all the colours of such original, except one, can be successively
and momentarily eliminated or rendered inactive.
Thus if an original is to be produced by means of three primary colours as
yellow, red and blue, we first treat the original so as to momentarily eliminate
the yellow and blue colours. We then in one form of our invention take a
photographic plate of the original, which plate will consequently only be a
photographic reproduction of the red part of the original.
We subsequently subject the original to a second treatment, by which we leave
the blue inactive, depriving at the same time the red of its activity and trans-
ferring the same to the yellow.
A second plate from the original will under these conditions be a photographic
reproduction exclusively of the yellow part of the original.
By a subsequent third treatment we only leave to the blue its activity, so that
on taking a third plate we obtain a photographic reproduction only of the blue
portion of the original.
Instead of taking photographic plates we may make a lithographic, zincographic
or similar transfer directly from the original for each colour.
Three photographic plates or three lithographic transfers are thus obtained
which on being superposed will reproduce the whole original with its colours with
great exactness.
As regards the reproduction of the original by printing processes the printing
plates or blocks may be produced by the aid of the photographic plate or of
lithographic transfers or other ordinary processes such plates being subsequently
used as is usual in colour printing.
A method of reproducing coloured originals has heretofore been proposed con-
sisting in taking successive photographic plates of the original by interposing,
at each operation, a coloured screen between the original and the object lens, and
letting pass only one kind or set of coloured rays each time, but this process
presents difficulties and inconveniences in carrying it out.

page_text: As an example of the manner of carrying out our process we will assume that
we are about to reproduce on some suitable material an original in which three
primary colours as yellow red and blue are employed.
For the red we employ iodide of mercury; for the yellow: ferrocyanide of
silver; and for the blue (which does reproduce by photography) a mixture of blue
aniline lac or of Berlin blue mixed with sulphate of lead.
These colours are powdered and mixed separately with the white of eggs and
made up in the form of paint, crayons, inks, or the like so that they may be
used to produce their colours or mixtures of same in the usual way.
After the original has been produced it is subjected to a series of treatments,
which in the particular, case in question are the following:
By the aid of a 'solution of sulphate of soda, the yellow is caused to disappear,
and as the blue is non actinic, there only remains the red. From this the first
plate or reproduction is made.
The silver salt which was forming the yellow is next reduced by using slightly
alkaline pyrogallic acid and thus the yellow is caused to re-appear in black. The
red is removed by cyanide of mercury.
Having then no further active agent upon the original than that which formed
the yellow, the second plate or reproduction is made.
The silver reduced is next removed by means of iodized cyanide, so that only
blue remains, and of this the lead salt that enters into its mixture is developed
by means of an alkaline sulphide, and a third plate or reproduction is made.
It will be understood that the process is not limited to the specific composition
of the colours indicated, nor to the reagents employed for rendering them tem-
porarily active or inactive, as substances may be employed in the colours which
may be acted upon with the object in view, for instance by heat, the effect of
which would be to volatilise the substance, or by electricity which would decom-
pose the substance in a suitable manner, or even by light.
In short all that is necessary is that the primary colours of the original be of
such a composition that by a direct and immediate action upon the constituent
substances, it is possible to render the colours active or inactive from the photo-
graphic point of view.
Among the advantages of the invention we may mention especially: rapidity
of execution; economy: no necessity for retouching operations; and precision
in the superposition of the plates in the printing process.
Dated this 29th day of November 1800
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Chartered Patent Agent,
For the Applicant.
Improvements in Reproducing on Paper, Fabrics, or other Materials
Facsimiles of Colored Originals.
We, THEODORE TRUCHELUT, of No. 34, Quai des Orfèvres, Paris, Chemical
Engineer, and AMÉDÉE AUGUSTE ROCHEREAU, of No. 36, Rue Merlin Thionville,
Suresnes, Department of Seine, Mechanic, both in France, 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:
The invention relates to improvements in reproducing on paper, fabrics, or
other materials facsimiles of colored originals.

page_text: According to our process the original (drawing, painting, water colour, crayon.
drawing, pastel, or the like) is prepared by the artist, by the aid of fundamental
colours, from which the entire gamut of tones and intermediate shades can be
obtained by mixing, just as is usually done.
These fundamental colours, however, must not be selected without consideration
of their chemical composition, but on the contrary must consist of substances
whose chemical and actinic properties are such that under the treatment to which
the original is exposed, the whole of the colours in the original, except one, can
be successively and momentarily eliminated, that is to say, rendered inactive.
Thus if we suppose an original prepared by means of the three primary colours:
red, blue, and yellow, we first treat the original in such a manner as to eliminate
for the moment, say the yellow and blue. We then in one form of our invention
take a photographic plate or the like of the original, which will consequently be a
photograph of merely the red portion of the original.
We next subject the original to a second treatment by means of which the blue
is left inactive whilst at the same time the activity of the red is suppressed and
that of the yellow restored. A new photograph of the original taken under these
conditions will represent solely the yellow part of the original. By means of a
third treatment we then suppress the activity of the yellow, leave the red inactive,
and restore the activity of the blue, so that on taking a third plate or the like
the latter will merely reproduce the blue part of the original.
We have now three photographic plates or the like which when superimposed
will reproduce the original in its entirety with absolute precision. Of course in
so far as the reproduction of the original by printing is concerned this object is
effected by preparing from the above mentioned plates or the like by means of
the usual methods, printing blocks, with which the printing in colours can be
performed in the usual manner.
We think it right to mention that others, before us, have attempted a process
for reproducing originals in colours, by taking successive photographic plates of
the original, interposing at each operation, between the original and the lens a
coloured screen which in each case allowed only a certain class of coloured rays to
pass through.
This process, however, presents so many difficulties in manipulation and so many
inconveniences, and is moreover so distinct from the principle of our invention,
so far as concerns the means employed for attaining the industrial object in view,
that we only mention it in order to define the sphere of our invention.
Our process is evidently also applicable to the reproduction of originals contain-
ing only a portion of the primary colours; consequently the number of treatments
to which the original has to be exposed and the number of plates to be prepared
will vary accordingly.
We will now proceed to indicate, as an example and to give a clearer idea of
our invention, a specific method of executing the general process already described.
We will assume the case of an original in the three primary colours: yellow, red
and blue.
To prepare the original we employ iodide of mercury for the red, ferocyanide of
silver for the yellow, and for the blue (which does not reproduce by photography)
we make use of a mixture of aniline-blue lake (or Prussian blue) mixed with lead
sulphate.
These colours are finely ground, separately, along with the white of egg (egg
albumen) gum, fish glue, or other agglutinant vehicle, and made up in the shape of
blocks, crayons, liquid colours, or the like to enable the artist using them in
combination, to produce all shades or combinations of colour.
When completed the original is subjected to a series of baths, which in the
particular case now under consideration, may be as follows:-
By the aid of solution of barium chloride or of the chloride of some other
alkaline earth metal, to which a small quantity of aldehyde is added for the
purpose hereafter described, we cause the yellow to disappear; and as the blue

page_text: does not reproduce there remains only the red to be photographed. We therefore
take the first plate or the like from this.
Next, by means of potassium iodide, we reduce the silver salt constituting the
yellow, and, in so doing, cause the yellow to reappear, the potassium iodide at the
same time causing the red to vanish. Having now no other active material on
the original, except that composing the yellow portion, we take the second plate
or the like.
In the third stage, by removing the reduced silver by the aid of potassium
cyanide, we have only the blue left. This we develop, as far as the lead salt
in the mixture is concerned, by means of sodium sulphide or other alkaline
sulphide, and then take the third plate or the like.
To sum up; according to this method of procedure, the operation may be con-
ducted in the following manner:
Red: Iodide of mercury
Yellow Ferrocyanide of silver
Blue: A mixture of Prussian blue and lead sulphate
each mixed or
ground in fish
glue.
BATHS AND WASHINGS: AND TAKING PHOTOGRAPHIC REPRODUCTIONS.
(a.) The original is immersed in the barium chloride solution. No stirring
should be practised for a quarter of an hour in order that the aldehyde
contained in the solution may precipitate the fish glue. After this
period is at an end the bath is tilted, to remove the yellow.
(6.) Wash in pure water taking care that the water jet does not remove the
pellicle or layer of colour.
(c.) Take the first photographic plate or the like (red).
(a.) Immerse the original in the iodide of potassium solution; the yellow
will re-appear; agitate until the red has vanished.
(b.) Wash as above (1 b).
(c.) Take the second photographic plate or the like (yellow).
(.) Place the original into the potassium cyanide solution and agitate until
the final traces of yellow have disappeared.
(6.) Wash carefully with pure water for a considerable time.
(c.) Immerse the original in the sodium sulphide solution; the blue will
immediately turn black;
(.) Wash with pure water.
(e.) Take the third photographic plate or the like (blue).
e desire to state here that we make no general claim in respect to the reactions
ribed above and which are already well known. We only draw them from
lic sources in order to apply them for the carrying out of our new process.
rom what has been stated above, persons acquainted with art will readily
erstand that our process is not restricted to the indicated specific composition
he primary colours, nor to the reagents employed to render them momentarily
ve or inactive.
is also known that by using certain substances for use as primary colours
might be acted upon in the desired direction by, for instance, the influence
eat, which would volatilise one of the substances; or again by electricity which
Id produce a suitable decomposition, or even by the action of light.
hus, to sum up, it is sufficient for the primary colours used, to be of such
position that they may, by subjection to direct action on their constituent

page_text: materials, be rendered at will momentarily active or inactive in a photographic
sense.
Again, our process can be carried out in another way:
In place of photographic plates or the like a lithographic, zincographic or
similar transfer can be taken directly from the original. In such case we proceed
as follows:-
A single colour, yellow for example, is mixed with some fatty material, in such
a manner that when the transfer is taken, the yellow i.e. the fatty part, alone,
will take the ink. We thus have a first stone or plate representing nothing but
the yellow.
To take the second transfer, for instance the red, a second stone or plate coated
with gelatine is used. In compounding the red colour (but no other) a chromium
salt (for example) is taken which renders the gelatine insoluble; and by this
means, a transfer of the red alone, can be obtained in the usual way.
To take the third transfer, say the blue, a third stone or plate, coated with
albumen is used. In compounding the blue (but in none of the other colours) a
mercury salt (for example) is employed. This renders the albumen insoluble and
a transfer of the blue alone can then be obtained in the usual way.
Again the three blocks or the like, red, blue, and yellow can be obtained in
another way, without resorting to photography, by proceeding as follows:
The colouring matters, properly so called, are not chemically active, but
merely serve as indicators.
The colours contain insoluble substances, such for example as tannates,
chromium salts, or cachou, which are then applied on a surface, previously coated
with gelatine and moistened with water and some other substance, such as a
chromate, pyrogallic acid or the like, so that the gelatine is precipitated suc-
cessively, and an image obtained by the difference in moisture; such as is already
practised in the autotype process, where the operator on dissolving the gelatine in
hot water only dissolves out the precipitated portions, as in the carbon process.
In yet another manner of carrying out our process the colours are prepared in
the same way as for the photographic method first described.
The original however is painted on a transparent ground such as paper, celluloid,
or the like.
In place however of taking photographs of the original, transparency printings
are made direct in the same manner as in printing a photographic positive from
the negative. This printing can be done direct on the stone or metal plate,
previously sensitised.
In conclusion it may be mentioned that by our process it is possible io
reproduce not only flat images but also all objects of different dimensions; and
that the series of blocks for colour printing obtained by our process and repro-
ducing the original when superimposed, may be used for reproduction in colours
on any suitable material.
Among the numerous advantages offered by our process we would specially
particularise the rapidity of execution: economy: entire suppression of retouch-
ing; and the mathematical accuracy of the superimposition of the blocks.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is:-
1. An original prepared for reproduction in colours, the primary colours of
which are so prepared that, by means of suitable methods of treatment, each can
be rendered momentarily active or inactive at will substantially as and for the
purpose described.
2. A process for reproducing an original of the kind described in the preceding
claim consisting in treating same in such a maner as to successively render
active a single one of the primary colours, the others being rendered inactive;

page_text: then taking a photographic plate or the like.or. lithographic, zincographic, or
other transfer direct from the original, of each of the colours whilst in its active
condition; and then producing from the said photographic plates or the like, or
lithographic, zincographic, or other transfers, a similar number of printing blocks,
which when printed by superimposition will furnish a reproduction in colours of 5
the original substantially as described.
Dated this 10th day of August 1900.
PHILIP M. JUSTICE,
Chartered Patent Agent, London, for the Applicant.