A PROCESS AND COMPOSITIONS FOR ENGRAVING UPON GLASS, METAL, AND STONE BY PHOTOGRAPHIC MEANS
Year: 1879

page_text: LETTERS PATENT to Firmin Kaiser and Arthur Auguste Duplessy, both of
Havre, in the Department of the Seine Inférieure, and Republic of France,
Merchants, for the Invention of A PROCESS AND COMPOSITIONS FOR
ENGRAVING UPON GLASS, METAL, AND STONE BY PHOTOGRAPHIC MEANS."
"
PROVISIONAL SPECIFICATION left by the said Firmin Kaiser and Arthur
Auguste Duplessy at the Office of the Commissioners of Patents on the 15th
March 1879.
FIRMIN KAISER and ARTHUR AUGUSTE DUPLESSY, both of Havre, in the Depart-
ment of the Seine Inférieure, and Republic of France, Merchants. "A PROCESS AND
COMPOSITIONS FOR ENGRAVING UPON GLASS; METAL, AND STONE BY PHOTOGRAPHIC
MEANS."
This new process permits the reproduction by means of fat inks of the photo-
graphic pictures obtained upon a preparation applied directly upon either
lithographic stones, plates of metal, such as zinc or copper, &c., and of engraving
these pictures either for typographic or for copper plate printing, whatever may be
their nature, whether portraits, engravings, drawings, paintings, etc. It applies also
to engraving upon glass.
«
"
It is based upon a novel chemical preparation sensitive to light, which permits
the sensitizing of fatty and resinous bodies such as all kinds of bitumen, copal, and
other varnishes prepared with spirit or oil, caoutchouc, gutta percha, pitch, Canada
balsam, or balsam of Peru. We have given to this new product the name of
It is one of the constituent principles of coal or of mineral pitch.
Mixed with one of the above mentioned bodies it constitutes the sensitive prepa-
ration; it is this preparation which is applied upon stone, plates of metal, glass,
and even paper, dried in the dark, then exposed to light beneath a cliché or photo-
graphic negative, or under a drawing upon paper; it has the property of becoming
insoluble as to the parts which have been struck by the light.
The picture is developed by means of olive oil, of hogs' lard, of petroleum, or of
benzine, used either singly or in combination, according to the substances employed.
For example, if a copal or other-hard varnish has been chosen the development with
Price Ad I

page_text: olive oil alone will be very difficult, a little petroleum or benzine should be added
to the oil, according to the hardness of the varnish.
As to the mode of operating, it consists in putting a little of this mixture upon a
cotton pad, and then rubbing round as in cleaning a plate. A few seconds suffice
to make the picture appear with all its details. It is easy to ascertain the proper
moment for ceasing the development.
The proof is then wiped with a fine clean linen cloth to remove the thick or fat
bodies. Then an exposure to light during five minutes hardens the whole surface.
The inking may then be attended to. If the proof is upon a lithographic stone,
all that is required to acidulate it is to steep it in a basin of nitric acid diluted with
water, the strength of which should vary according to the hardness of the stone,
say, 6 to 8 parts by weight of acid to 100 of water (6 to 8 grammes to 100
grammes). Three minutes will usually suffice. If the proof is upon zinc, copper,
or other metal, acids will be used suitable for these metals, and always diluted with
water in the proportion of ten to twenty parts of acid for 100 parts of water (10 to
20 grammes to 100 grammes).
Proofs may be obtained directly upon paper by the same method, with all the
half tints of a cliché or negative taken from nature. The process is as follows:-
Upon a sheet of Bristol board is placed a layer of collodion in its normal state, the
object of which is to prevent the composition penetrating into the paper. A thin
layer of gelatine would produce about the same effect. The operation then takes
place upon the sheet thus prepared, as when the stone or metal plates are used;
that is to say, that it is covered with a layer of the composition applied either with
a brush or by pouring it on, as is done by photographers in spreading collodion.
This kind of photography, formed of a resinous body, to which may be added a
colouring substance, according to the tone desired, is unalterable.
If the proof is obtained upon glass the engraving is executed by means of fluor-
bydric acid, either liquid or in vapour, according to the effect sought to be
produced.
For engraving metals, either in copper plate or typographically, the following is
the manner of operating the developments.
Take, by preference, a composition of india-rubber and asphaltum or Jews' pitch
in equal parts, diluted with a little ether or sulphuret of carbon to hasten the
drying on the metal. Expose to the light from five to fifteen minutes in a frame
and under a cliché or photographic stereotype or negative plate rather weak than
strong, especially if it is a cliché from nature. For the development the plate is
dipped into a bath of spirit of petroleum, and the proof'immediately appears.
In the case of a somewhat lengthened exposure to the light, gasoline or benzine
may be used instead of petroleum. The proof is then washed' by letting water run
over the plate. Dried at a gentle fire it becomes stronger.
After the development the white parts of the proof are still-veiled by a very
slight layer of india rubber incompletely dissolved; but this sort of veil, far from
being subsequently a hindrance to the engraving of the metal' is on the contrary
advantageous, because it favours and regulates the action of the nitric acid mixed
with alcohol.
When the proof is considered to be engraved or bitten in to a sufficient depth it
is again washed, and then dried. In the contrary case the proof may be again
inked with a fat ink and the acid be made to bite again!
If; after exposing to the light; the picture is developed' with ether instead of
petroleum, a sheet engraved in copper plate will be obtained with an ordinary
cliché, because the ether preferably dissolves the bitumen, while the petroleum on
the contrary dissolves the india rubber:
Thus, according to the development employed; there may be obtained from the
same cliché a picture which may give a reproduction either for copper plate or for
typography.
Proofs developed on metallic plates may also be used without being engraved,
and the working off be operated directly from the' plate by acidulating before

page_text: commencing the inking with a composition of about 1/8th of an ounce (six grammes)
of gallic acid, about an ounce (thirty grammes) of gum arabic dissolved in a quart
("litre") of water, and about 1/1 th of an ounce (two grammes) of nitric acid.
14
Preparation of the sensitive composition :-
Take either copal varnish or any other spirit varnish known to commerce, dilute
it to the extent of one half at least with spirit of turpentine, add bitumen, caout-
chouc, or gutta percha, also dissolved in the spirit, pour this solution into a quart of
diluted varnish, to which add, to make it sensitive, nearly an ounce (twenty
grammes) of "Resinaline."
The proportions above given may vary according to the thickness of the layer or
the kind of engraving which it is desired to obtain.
This preparation will preserve for an indefinite period without any deterioration.
Being sensitive only when it is dry, it is not necessary to withdraw it from the
light, but the bottle or vessel containing it should be well stoppered.
The following compositions might also be employed:-A solution of Jews' pitch
in spirit of turpentine, or a solution of caoutchouc in the same spirit, both rendered
sensitive by nitrate of uranium. These compositions are equally sensitive, and may
give proofs such as those above described.
The product termed "Resinaline" is obtained with the mineral tar or pitch
coming from the residuum of coal from gasworks; sulphuric ether or other spirit is
poured on to these residuums, and a liquid is obtained of a golden yellow colour.
which is the sensitive product which we term "Resinaline."

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Firmin Kaiser and Arthur Auguste Duplessy in the Great Seal
Patent Office on the 13th September 1879.
FIRMIN KAISER and ARTHUR AUGUSTE DUPLESSY, both of Havre, in the Depart-
ment of the Seine Inférieure, and Republic of France, Merchants. "A PROCESS AND
COMPOSITIONS FOR ENGRAVING UPON GLASS, METAL, AND STONE BY PHOTOGRAPHIC
MEANS."
This new process permits the reproduction by means of fat inks of the photo-
graphic pictures obtained upon a preparation applied directly upon either litho-
graphic stones, plates of metal, such as zinc or copper, etc., and of engraving these
pictures either for typography or for copper plate printing, whatever may be their
nature, whether portraits, engravings, drawings, paintings, etc. It applies also to
engraving upon glass.
It is based upon a novel chemical preparation sensitive to light, which permits
the sensitizing of fatty and resinous bodies such as all kinds of bitumen, copal, and
other varnishes prepared with spirit or oil, caoutchouc, gutta percha, pitch, Canada
balsam, or balsam of Peru. This product, hereinafter referred to as Resinaline,"
is one of the constituent principles of coal or of mineral pitch.
"
Mixed with one of the above mentioned bodies it constitutes the sensitive
preparation; it is this preparation which is applied upon stone, plates of metal,
glass, and even paper dried in the dark, then exposed to light beneath a "cliché" or
photographic negative, or under a drawing upon paper it has the property of
becoming insoluble as to the parts which have been struck by the light.
The picture is developed by means of olive oil, of azunge, or hogs lard, of petroleum
or of benzine, used either singly or in combination, according to the substances
employed. For example, if a copal or other hard varnish has been chosen, the
developement with olive oil alone will be very difficult; a little petroleum or
benzine should be added to the oil, according to the hardness of the varnish.
As to the mode of operating, it consists in putting a little of this mixture upon a
cotton pad or tamkin and then rubbing round as in cleaning a plate, a few seconds
suffice to make the picture appear with all its details. It is easy to ascertain the
proper moment for ceasing the developement. The proof is then wiped with a fine
clean linen cloth to remove the thick or fat bodies; then an exposure to light
during five minutes hardens the whole surface.
The inking may then be attended to. If the proof is upon a lithographic stone 3
all that is required to acidulate it is to steep it in a basin of nitric acid diluted
with water, the strength of which should vary according to the hardness of the
stone, say 6 to 8 parts by weight of acid to 100 of water (6 to 8 grammes to
100 grammes). Three minutes will usually suffice.
If the proof is upon zinc, copper, or other metal, acids will be used suitable for 4
these metals, and always diluted with water in the proportion of ten to twenty
parts of acid for 100 parts of water (10 to 20 grammes to 100 grammes).
A thin
Proofs may be obtained directly upon paper by the same method, with all the
half tints of a "cliché" or negative taken from nature, the process is as follows:-
Upon a sheet of Bristol board is placed a layer of collodion in its normal state, the 4
object of which is to prevent the composition penetrating into the paper.
layer of gelatine would produce about the same effect. The operation then takes
place upon the sheet thus prepared, as when the stone or metal plates are used,
that is to say, that it is covered with a layer of the composition applied either with
a brush or by pouring it on as is done by photographers in spreading collodion.
5

page_text: This kind of photography, formed of a resinous body to which may be added a
colouring substance, according to the tone desired, is unalterable.
If the proof is obtained upon glass, the engraving is executed by means of
fluorhydric acid, either liquid or in vapour, according to the effect sought to be
produced.
For engraving metals either in copper-plate or typographically the following is
the manner of operating the developements.
under a
Take, by preference, a composition of india-rubber and asphaltum or Jews' pitch
in equal parts, diluted with a little ether or sulphate of carbon to hasten the drying
on the metal. Expose to the light from five to fifteen minutes in a frame and
"cliché" or a photographic stereotype a negative plate rather weak than
strong, especially if it is a "cliché" from nature. For the developement the
plate is dipped into a bath of spirit of petroleum and the proof immediately
appears.
In the case of a somewhat lengthened exposure to the light, gasoline or
benzine may be used instead of petroleum. The proof is then washed by letting
water run over the plate. Dried at a gentle fire it becomes stronger.
After the developement, the white parts of the proof are still veiled by a very
slight layer of india-rubber incompletely dissolved; but this sort of veil far from
being subsequently a hindrance to the engraving of the metal is, on the contrary,
advantageous, because it favours and regulates the action of the nitric acid mixed
with alcohol.
:
When the proof is considered to be engraved or bitten in to a sufficient depth it
is again washed and then dried. In the contrary case the proof may be again
inked with a fat ink and the acid be made to bite again.
If after exposing to the light the picture is developed with ether instead of
petroleum a sheet engraved in copper plate ("tailledouce") will be obtained with
an ordinary "cliché," because the ether preferably dissolves the bitumen, while the
pétroleum on the contrary dissolves the india rubber.
Thus according to the developement employed there may be obtained from the
same "cliché" a picture which may give a reproduction either for copper plate
printing or for typography.
Proofs developed on metallic plates may also be used without being engraved,
and the working off be operated directly from the plate by acidulating before
commencing the inking with a composition of about 91-592 grains ("6 grammes") of
gallic acid, about 462-96 grains (30 "grammes") of gum arabic dissolved in about a
quart ("litre") of water, and about 30-864 grains (2 "grammes") of nitric acid.
Preparation of the Sensitive Composition.-Take either copal varnish or any
other spirit varnish known to commerce, dilute it to the extent of one half at least
with spirit of turpentine, add bitumen, india rubber, or gutta percha also dissolved
in the spirit; pour this solution into a quart (litre) of diluted varnish, to which
add to make it sensitive 308-64 grains ("20 grammes") of "Resinaline."
The proportions above given may vary according to the thickness of the layer or
the kind of engraving which it is desired to obtain.
This preparation will preserve for an indefinite period without any deterioration.
Being sensitive only when it is dry it is not necessary to withdraw it from the
light, but the bottle or vessel containing it should be well stoppered.
P
The following compositions might also be employed :-A solution of Jews' pitch
in spirit of turpentine, or a solution of india rubber in the same spirit, both
rendered sensitive by nitrate of uranium. These compositions are equally sensitive
and may give proofs such as those above described.
The varnishes may be rendered more drying by using sulphuric ether, sulphuret
of carbon, or any other drying essence or spirit without prejudice to the sensitive-
ness of the compositions.

page_text: <
Preparation of the Composition.-The bitumen is pulverized and melted over
the fire with a little spirit or essence. When thoroughly melted it is removed
from the fire and the above mentioned matters are added to it. We use the gutta
percha and the bitumen, not on account of their sensitiveness, which is very slight,
but to give body to the composition, which will permit it to resist the action of the
acids in engraving. These substances might therefore be replaced by the residue of
coal tar or pitch, paraffine, or wax.
As to the india rubber and gutta percha we prefer to dissolve them in Barbadoes
tar or mineral pitch, oil, and sulphuret of carbon, and in the proportion of two
parts of india rubber to one part of gutta percha.
The Sensitizing of the Composition.-To render the composition sensitive to the
light we add to it the product which we term "Résinaline" obtained from the
residuums of coal from gas works, and principally from mineral tar or pitch. To
obtain the hatching or rough or granulated ground ("grain ") we add the nitrate of
uranium, which also possesses the property of rendering fatty and resinous matters
sensitive to light.
Method of Extracting the New Product which we term "Résinaline."—We take
about 4 lbs. 6 ozs. (2 "kilogrammes") of Barbadoes tar or mineral pitch, upon which
we pour about 7,716 grains ("500 grammes") of spirit of turpentine or of sulphuric
ether. This mixture is kept well stirred until the spirit or the ether has acquired
a golden yellow color. This liquid is the "Resinaline;" after standing a few
hours it is decanted and filtered through flannel or other suitable material.
Preparation of the Nitrate of Uranium.--We dissolve in 15432 grains (100
grammes") of ether, 462-96 grains (30 "grammes") of nitrate of uranium. This
is the solution which enters into the composition No. 3 in the proportion of 231·48
grains (15 "grammes").
Observations. For engraving on glass, which is our main object, we prefer to
use for polished glass the composition No. 2, for unpolished glass the composition
No, 1, and for lithography the composition No. 3.
Developement. For large proofs of two or three square yards we commence by
rubbing the entire surface with the azunge or hogs lard dissolved in oil; a quarter
of an hour afterwards the developement is continued. The object of this first
operation is to give time to the non-insolated parts to soften. The mode of working
which we find most suitable is to begin by soaking with azunge or hogs lard and
oil ten proofs of about one square yard; we then take these proofs successively,
beginning with that which was first prepared, and complete the developement.
If the exposure to the light has been too prolonged the mixture of hogs-lard and

page_text: fat oil may be insufficient for continuing the developement; this may also be the
case according to the composition used. No. 2 resists more than No. 1. In these
two cases the operator adds to the preceding mixture a little mineral essence or
turpentine. One day's work will suffice to enable an inexperienced workman to be
certain of success in producing either a soft or a powerful developement without the
necessity of instructing him as to the length of time for exposure to light. He
must simply proceed with caution so as not to spoil the proof in case it should have
been but slightly insolated.
Proofs which have been submitted to the action of the light for an entire day
may be very well developed with the essence or spirit and very little of the hogs
lard, particularly if the exposure has taken place under a drawing made by hand
instead of a photographic plate or "cliché."
The sensitiveness of the product which we term "Résinaline" is comparable to
that of paper prepared with chloride of silver. It mixes in any proportions with
the substances above specified. This product is extracted by distillation, either
with ether or with any kind of essence or spirit. Its sensitiveness is such that five
minutes exposure to the sun under a slightly transparent plate or "cliché" is
sufficient to obtain a good picture, with this great advantage, that this exposure
may be prolonged for twenty minutes without disadvantage. By a properly
conducted developement a good result will always be obtained. It is not necessary
that the developement should be operated in a very dark place; an apartment
feebly lit is sufficient if the developement takes place immediately.
This process opens a great field to industrial applications. Engravers, litho-
graphers, typographers, engravers upon glass, geographers, and others will find in
its use advantages not afforded by the processes of photography, phototypy, and
the other processes hitherto known.
Its advantages may be summed up as follows:-
1. Preservation for an indefinite period of the preparation of stones, metal plates
of any kind, papers and other materials kept in the dark.
2. Great latitude in the time of exposure to the light without endangering the
result.
3. Facility of developement almost dry, either immediately or several days
afterwards, if the piece has been kept in the dark.
4. Resistance of the preparations to all acids, which permits engraving upon any
kind of body or substance.
5. The obtaining of proofs of very great dimensions. In this case the litho
graphic stone may be replaced by a sheet of zine; for example, at the moment of
placing in the press we acidulate with a decoction of gall-nuts with the addition of
a little nitric acid, say, 30-864 grains (2 "grammes") to a quart ("litre") of water
and 308.64 grains (20 "grammes") of gum arabic.
6. A great number of proofs may be worked or pulled off owing to the resistance
of the compositions.
7. Facility of stopping the working off to resume it later. Upon stone prepared
by the process the working off is easier than upon a stone prepared in the ordinary
manner. When the working off is finished the printing ink is removed with a rag
soaked with olive oil and the stone is gummed. If it is desired at a later period to
recommence working off it is only necessary to remove the gum with water and to
ink afresh.
Having now described and ascertained the nature of our said Invention, and in
what manner the same is or may be performed, what
We claim as of our Invention and secured to us by the hereinbefore in part
recited Letters Patent is,-
Firstly. The means of sensitizing resinous varnishes and fatty bodies or matters
for the reproduction of photographic proofs of all kinds to be used for typographic
or lithographic printing, or engraving upon stone, zinc, copper, or other metal, glass,
and generally upon all hard bodies capable of receiving a polish, substantially as
herein before described. .

page_text: Secondly. The extract hereinbefore designated "Résinaline," composed and pre-
pared substantially as herein before described, and forming a new product for
sensitizing fatty bodies or matters for photography. We in most cases give
preference to the use of the "Résinaline" unmixed with nitrate of uranium, but we
may use it in combination therewith, as herein-before described.
Thirdly. The method of sensitizing the above mentioned substances with nitrate
of uranium, either in combination with "Resinaline" or otherwise, according to the
object to be obtained, substantially as hereinbefore described.
In witness whereof, we, the said Firmin Kaiser and Arthur Auguste Duplessy,
have hereunto set our hands and seals this Eighth day of September, in the
year of our Lord One thousand eight hundred and seventy nine..
FIRMIN KAISER..
(L.S.)
ARTHUR AUGUSTE DUPLESSY. (LS.)