AN. IMPROVED PROCESS FOR PRODUCING PRINTING SURFACES
Year: 1865

page_text: LETTERS PATENT to Francis John Bolton, of Bruton Street, in the
County of Middlesex, Captain in Her Majesty's 12th Regiment of Foot,
and Henry Matheson, of Hackney, in the County of Middlesex,
Gentleman, for the Invention of "AN. IMPROVED PROCESS FOR PRODUCING
PRINTING SURFACES."
Sealed the 24th November 1865, and dated the 2nd June 1865.
PROVISIONAL SPECIFICATION left by the said Francis John Bolton and
Henry Matheson at the Office of the Commissioners of Patents, with
their Petition, on the 2nd June 1865.
We, FRANCIS JOHN BOLTON, of Bruton Street, in the County of Middlesex,
Captain in Her Majesty's 12th Regiment of Foot, and HENRY MATHESON, of
Hackney, in the County of Middlesex, Gentleman, do hereby declare the
nature of the said Invention for "AN IMPROVED PROCESS FOR PRODUCING
PRINTING SURFACES," to be as follows.:-
This Invention of an improved process for producing printing surfaces
has for its object to produce printing surfaces on stone, zinc, or other metal or
suitable substance, partly by the agency of light and partly by the action of
chymical agents on the surfaces to be operated upon, so that the surfaces when
prepared may be used for printing therefrom with ink, as is well-known in
lithographic, zincographic, and other printing operations. In carrying out our

page_text: Invention we take a lithographic stone prepared in the ordinary manner, or
a zinc or other plate, or suitable smooth surface, and in a darkened room we
coat the surface evenly with a composition consisting of equal quantities of
gum arabic, or gelatine, or starch, and bichromate of potash dissolved in
water. This coating must be thoroughly dried, and the photographic picture,
engraving, or other object to be copied is to be laid on the prepared surface,
face downwards. The stone plate or other surface with the picture or object on
it may then be exposed to the light for the proper time, according to the nature
of the picture or object to be copied, and after it has been sufficiently exposed,
it is to be taken back to the darkened room and there soaked for several
hours in clean cold water in order to wash out those parts which have not
been affected by the light. After it has been thoroughly dried the stone or
plate may be exposed to the light without fear of injury. A solution of alkaline
soap or of the components of such soap in turpentine is then poured over the
surface of the stove or plate and allowed to stand until the solvent or turpentine
has evaporated. This will leave the fatty salts in the pores of those parts of the
stone or surface of the plate which have not been acted on by the light. The stone
or plate must now be soaked thoroughly with a strong solution ofbichromate salt.
This will fix the picture, which may now be printed from with printer's ink in
the usual manner. Instead of producing the printing surface direct on the stone
or plate, we sometimes print the picture from the negative on to a sheet of
paper or other flexible material, and we transfer this picture from the paper
or flexible material to 'the stone plate or printing surface, from which any
number of prints may be taken in the ordinary manner. As a modification of
the above we also in some cases transfer the picture from the negative to a
thin sheet of metallic foil, the surface of which is rendered sensitive, and
prepared in the manner already explained. When the picture has thus been
transferred to the flexible metallic surface, the latter may be fixed on a
block or otherwise backed up, so that it may be printed from in the ordinary
manner.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Francis John Bolton and Henry Matheson in the Great
Seal Patent Office on the 2nd December 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, FRANCIS
JOHN BOLTON, of Bruton Street, in the County of Middlesex, Captain in Her
Majesty's 12th Regiment of Foot, and HENRY MATHESON, of Hackney, in the
County of Middlesex, Gentleman, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Second day of June, in the year of our Lord One
thousand eight hundred and sixty-five, in the twenty-eighth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto us, the said
Francis John Bolton and Henry Matheson, Her special licence, that we, the
said: Francis John Bolton and Henry Matheson, our executors, administrators,
and assigns, or such others as we, the said Francis John Bolton and Henry
Matheson, our 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 IMPROVED
PROCESS FOR PRODUCING PRINTING SURFACES," upon the condition (amongst
others) that we, the said Francis John Bolton and Henry Matheson,
our executors or administrators, by an instrument in writing under our, 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 we, the said Francis John Bolton and Henry Matheson
do hereby declare the nature of our said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in and
by the following statement (that is to say): :-
'
This Invention of "an improved process for producing printing surfaces has
for its object to produce printing surfaces on stone, zinc, or other metal or
suitable substance, partly by the agency of light, and partly by the action of
chemical agents on the surfaces to be operated upon, so that the surfaces when
prepared may be used for printing therefrom with ink, as is well known in
lithographic, zincographic, and other printing surfaces. In carrying out our
Invention we take a lithographic stone prepared in the ordinary manner, or a
zinc or other plate or suitable smooth surface, and in a darkened room we
coat the surface evenly with a composition consisting of gum arabic, gelatine,
or starch and bichromote of potash, or other base, depending upon the nature
of the subject to be taken (dissolved in water. This coating must be thoroughly
dried, and the photographic picture, engraving, or other object to be copied is.
to be laid on the prepared surface face downwards. The stone plate or other
surface with the picture or object on it may then be exposed to the light for
the proper time, according to the nature of the picture or object to be copied,

page_text: and. after it has been sufficiently exposed it is to be taken, back to the
darkened room, and there soaked for several hours, with the prepared surface
downwards, in clean water, in order to wash out the undecomposed gum from
those parts which have not been affected by the light. It is of essential
importance to the success of the operation that the undecomposed gum should
be thoroughly washed out or removed from the plate, otherwise the picture
will be defective. The plate must therefore be soaked for a lengthened time
as before mentioned; and it is important that it should be placed in the bath
face downwards, so that the gum as it dissolves shall by its specific gravity
leave the surface of the stone or plate, and be deposited at the bottom.of the
bath. After it has been thoroughly dried, the stone or plate may be exposed
to the light without fear of injury. The surface thus treated leaves a film in
the parts decomposed by the light impermeable to the solution herein-after
described, provided water or other. liquids or substances capable of softening
the film are carefully excluded in the preparation of the said solution, and
which exclusion we are careful to observe. A solution of alkaline soap or of
the components of such soap, freed as much as possible from moisture and
other substances capable of softening the film is then prepared, the soap is
dissolved in turpentine (or other solvent free as possible from water will do as
well). This solution is then poured or spread over the surface of the stone
or plate and allowed to stand until the solvent or turpentine has evaporated.
This will leave the fatty salts in the pores of those parts of the stone or surface
of the plate which have not been acted on by the light; the stone or plate
must now be soaked thoroughly with a strong solution of bichromate salt. The
stone should be previously rinsed with water or a liquid containing water to
remove the superfluous soap or its components, and to ensure the adhesion of
the ink in the after process of printing. Other salts, acids, or substances
capable of decomposing the soap or its components without decomposing the
stone or other support to the. film will answer the same purpose, but we
prefer to use a bichromate. The bichromate salt or other suitable substance
us above mentioned, will fix the picture tenaciously to the stone or other
material, and will prevent spreading or blurring of the fine detail. This effect
is produced by the alkali or oxides of the soap or fatty salts combining with
the chromic acid of the bichromate salts and precipitating the fatty acids.
The surface thus prepared may now be printed from with printer's ink in the
usual manner.
Instead of producing the printing surface direct on the stone
or plate, we sometimes print the picture from the negative on to a sheet of
paper or other flexible material, in which case the saponaceous solution should
be applied from the back and the solvent of which may be water, the manipulation

page_text: being otherwise the same. We transfer the picture, which must be damp,
from the paper or flexible material to the stone plate or printing surface, from
which any number of prints may be taken in the ordinary manner.
It will
be understood that this process may be adapted to chromo-lithographic printing,
as several surfaces prepared as above may be used for producing pictures in
color in the usual manner of color printing. As a modification of the above,
we also in some cases print the picture from the negative on to a thin sheet
of metallic foil, the surface of which is rendered sensitive and prepared in the
manner already explained. When the picture has thus been transferred to
the flexible metallic surface, the latter may be fixed on a block or otherwise
backed up, so that it may be printed from in the ordinary manner.
Having now described our Invention of an improved process for producing
printing surfaces, and having explained the manner in which the same is to be
performed, we claim as the Invention secured to us by Letters Patent as
aforesaid the process herein set forth for producing printing surfaces by the
agency of light in combination with chemical substances.
In witness whereof, we, the said Francis John Bolton and Henry
Matheson, have hereunto set our hands and seals, the Second day of
December, in the year of our Lord One thousand eight hundred and
sixty-five.
FRANCIS JOHN BOLTON. (L.S.)
HY. MATHESON.
(L.B.)