AN IMPROVEMENT IN PRE- PARING PLATES FOR PRINTING
Year: 1858

page_text: LETTERS PATENT to Edmond Auguste Jacquin, of Rue des Lavandières,.
Ste Opportune, Paris, for the Invention of "AN IMPROVEMENT IN PRE-
PARING PLATES FOR PRINTING."-A communication from Monsieur Henry
Garnier, of Paris.
Sealed the 27th August 1858, and dated the 29th March 1858.
PROVISIONAL SPECIFICATION left by the said Edmond Auguste Jacquin
at the Office of the Commissioners of Patents, with his Petition, on
the 29th March 1858.
I, EDMOND AUGUSTE JACQUIN, of Rue des Lavandières, Sto Opportune;
Paris, do hereby declare the nature of the Invention for "AN IMPROVEMENT IN
PREPARING PLATES FOR PRINTING," to be as follows:-
This Invention has for its object an improvement in preparing engraved
plates of copper or other metal for printing, in order to render them more
durable, or so that a greatly increased number of impressions may be obtained
from such engraved plates. For this purpose, when the plate of copper or
other comparatively soft metal has been engraved in the ordinary manner, a
thin coating of iron is deposited on to it by electricity from a bath containing
a solution of that metal; from the plate so prepared impressions may be
printed by the usual method, and the printing may be continued until the
coating begins to be worn through, but this will not take place until 'very'
many impressions have been obtained. If a further number of impressions is
required, the worn coating of iron may be dissolved off from the plate and a
fresh coating of iron deposited thereon; afterwards the printing may be
recommenced as before, and by thus from time to time renewing the coating
of iron almost any number of impressions may be taken from the engraved
plate.

page_text: In some cases, particularly when the plate is not engraved by hand, but by
mechanical or chemical means, as is sometimes practiced, it is convenient to
coat the plate of copper or other metal with iron before producing the design
upon the plate.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edmond Auguste Jacquin in the Great Seal Patent Office
on the 25th September 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDMOND
AUGUSTE JACQUIN, of Rue des Lavandières, Sto Opportune, Paris, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of March, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Edmond Auguste Jacquin, Her special licence that I, the said Edmond
Auguste Jacquin, my executors, administrators, and assigns, or such others
as I, the said Edmond Auguste Jacquin, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United Kingdom
of Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "AN IMPROVEMENT IN PREPARING PLATES FOR PRINTING," (a
communication from Monsieur Henry Garnier, of Paris,) upon the con-
dition (amongst others) that I, the said Edmond Auguste Jacquin, my
executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great Seal
Patent Office within six calendar months next and immediately after the
date of the said Letters Patent.
NOW KNOW YE, that J, the said Edmond Auguste Jacquin, do hereby.
declare the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by.
the following statement thereof, that is to say:-
This Invention has for its object certain means of preparing printing
surfaces, whether for intaglio or surface printing, so as to give them the

page_text: property of yielding a considerably greater number of impressions than they
are capable of doing in their ordinary or natural state. And the Invention
consists in covering the printing surfaces, whether intaglio or relief, and
whether of copper or other soft metal, with a very thin and uniform coating of
iron by means of electro-metallurgical processes. And the Invention is
applicable whether the device to be printed from be produced by engraving by
hand, or by machinery, or by chemical means, and whether the surface printed
from be the original or an electrotype surface produced therefrom. I would
remark that I am aware that it has been before proposed to coat type and
stereotypes with a coating of copper to enable their surfaces to print a larger
number of impressions than they otherwise would do; I therefore lay no claim
to the general application of a coating of harder metal on to the surface of a
softer one, but my claim to invention is confined to the application of a coating
of iron by means of electricity on to copper and other metallic printing
surfaces.
In carrying out the Invention the solutions of iron employed may be varied,
and such is the case in respect to the arrangement of galvanic battery or other
source of electric currents used; I do not therefore limit the Invention to the
means herein-after described, but I believe they will be found to be the best
for the
purpose.
I would further remark that it is important that a ferric solution should be
employed which will not dissolve or corrode the plate intended to be coated,
for if it be attempted to use such a solution, though the iron will be pre-
cipitated, it will not only be in a non-coherent state, but the engraved surface
itself will be liable to be attacked and injured. It may also be remarked that
the coating of iron admits of being removed from a printing surface of copper
without injury to the original plate, hence the original plate may, after being
coated and used for some time, have the worn coating removed, and then be
re-covered with an iron coating as often as may be required; and if care is
taken to remove the coating of iron before it has been entirely worn away,
the engraved copper or other plate may be made to print a vast number of
impressions and yet remain in the original state it was in when it left the
hands of the engraver, or was otherwise first produced; the only limit appears
to be in the gradual change which takes place in the body of the printing
surface by the compression to which it is subjected in the process of printing.
Heretofore, in respect to plates engraved in intaglio, if of steel, they each yield
on the average about 3000 impressions without retouching; if of copper they
each yield on an average not more than 800 without retouching; whilst
electro casts of copper obtained from the originals will not on an average each

page_text: yield even 200 impressions without retouching; in fact such printing surfaces
are so easily worn, that after the first hundred or 150 impressions there is a
considerable deterioration in the quality of.the work produced. Therefore, for
the supply of the number of impressions often required by art associations and
others, it has been found necessary to multiply the electro casts very con-
siderably. In such cases the Invention is applicable with considerable
advantage, for I find that an electro plate 40 × 22 inches covered or. coated
with iron has yielded 2000 impressions without its being necessary to remove
and renew the iron coating, there being no perceptible difference between the
first and last impression, the work on the plate appearing not to have suffered
in the slightest degree. Hence in future, by the application of the Invention;
it will only be necessary to multiply electro casts to such an extent as may be
necessary to ensure the production of prints or impressions with the requisite
speed on paper, calico, or other fabrics. At the same time an original
engraving on copper would become, when treated according to the Invention,
more lasting than if engraved on steel. Although original surfaces engraved
in relief, and also electro and other casts taken from them, yield a considerably
greater number of impressions than those I have mentioned as obtained from
plates engraved in intaglio, to which the Invention has not been applied,
nevertheless the Invention is applicable with great advantage to such relicf
printing surfaces, whether of copper or other soft metal, for if they be coated
with iron according to the Invention they will yield almost an indefinite
number of impressions, provided the iron surface be renewed as often as may
be necessary, and the printing surfaces be again re-coated.
In carrying out the Invention I prefer to use that modification of Grove's
battery known as Bunsen's, and I do so because it is desirable to have what
is called an intensity arrangement. The trough I use for containing the
solution of iron. in which the engraved printing surface is to be immersed in
order to be coated is lined with gutta percha, and it is 45 inches long, 22
inches wide, and 32 inches deep. In proceeding to prepare for work the
trough, whether of the size above-mentioned or otherwise, is filled with water
in combination with hydrochlorate of ammonia (salammoniac) in the pros
portion of one thousand lbs. by weight of water to one hundred lbs. of
hydrochlorate of ammonia. A plate of sheet iron nearly as long and as deep
as the trough is attached to the positive pole of the battery and immersed in
the solution. Another plate of sheet iron about half the size of the other is
attached to the negative pole of the battery and immersed in the solution, and
when the solution has arrived at the proper condition, which will require
several days, the plate of iron attached to the negative pole is removed;

page_text: and the printing surface to be coated is attached to such pole, and then
immersed in the bath till the required coating of iron is obtained thereto. If,
on immersing the copper plate in the solution, it be not immediately coated
with a bright coating of iron all over, the bath is not in a proper condition,
and the copper plate is to be removed and the iron plate attached and returned
into the solution. The time occupied in obtaining a proper coating of iron to
a printing surface varies from a variety of causes, but a workman after some
experience and by careful attention will readily know when to remove the
plate from the solution; and it is desirable to state that a copper plate should
not be allowed to remain in the bath and attached to the negative pole of the
battery after the bright coating of iron begins to show a blackish appearanco
at the edges. Immediately on taking a copper plate from the bath great
care is to be observed in washing off the solution from all parts, and this I
believe may be most conveniently done by causing jets of water forcibly to
strike against all parts of the surface. The plate is then dried and washed
with spirits of turpentine, when it is ready for being printed from in the
ordinary manner. The Bunsen's battery used by me with the trough above
described is as follows:-
Twenty elements in series of five;
Earthen jar, 9 inches, and 5
Zinc
-
each clement is composed of an-
inches diameter.
8 inches, 4 inches diameter, and th inch thick.
Porous cell 8 inches, and 24 inches diameter.
Carbon
-
9 inches by 2 inches in width, and 1 inch in thickness.
It should be observed that the battery will require attention when in use, as
its action will diminish, the acids must therefore be removed gradually by
adding fresh acids every two or three days. In order to remove the coating
of iron from a printing surface after the iron coating has become worn I
employ a solution which will act on the iron without attacking the printing
surface. In removing iron from copper, nitric acid is used diluted with eight
parts of water, and care is to be taken to wash off the solution as soon as the
iron is dissolved.
In witness whereof, I, the said Edmond Auguste Jacquin, have hereunto
set my hand and scal, this Sixteenth day of September, in the year of
our Lord One thousand eight hundred and fifty-eight.
E. A. JACQUIN. (L.S.)