IMPROVEMENTS IN STEREOTYPE PLATES
Year: 1868

page_text: LETTERS PATENT to George Rowe Wilson, of Birmingham, in the
County of Warwick, India-rubber Manufacturer, for the Invention
of "IMPROVEMENTS IN STEREOTYPE PLATES"
Scaled the 5th January 1869, and dated the 7th July 1868..
PROVISIONAL SPECIFICATION left by the said George Rowe Wilson at
the Office of the Commissioners of Patents, with his Petition, on the
7th July 1868.
I, GEORGE ROWE WILSON, of Birmingham, in the County of
Warwick, India-rubber Manufacturer, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN STEREOTYPE PLATES," to be as
follows:-
The said Invention relates to stereotypes formed of vulcanized
india-rubber or gutta percha, or a compound of both substances, and
consists chiefly in the novel modes or processes employed to produce
the impressions in or upon the india-rubber or other material. The

page_text: said impressions are produced either upon the finished vulcanized sheets
or in the soft compound of which such sheets are formed, the curing
or vulcanizing being in the latter case afterwards effected by the usual
means. The rubber or other material and the matrix are clamped
together and subjected to heat. After cooling the vulcanized plate
is removed from the matrix and is ready for use.
According to one method of practising my Invention, I take a sheet
of hard prepared india-rubber such as is commonly known as "vulcanite "
or a sheet of prepared vulcanized gutta percha, or a sheet of the two
substances combined, and soften the same by placing upon it a heated
metal plate. The matrix or mould from which I desire to obtain the
stereotype is then placed upon the softened rubber or other substance.
Behind the matrix I place another plate of iron or other metal. These
two plates with the rubber and matrix between them as above described
are then by means of screws or other suitable means clamped or bound
together and allowed to remain so till they are cold. By this means
an exact and perfect copy of the matrix is obtained upon the surface
of the vulcanized plate. The metal plates may then be unfastened
and the stereotype removed from the matrix. I vary the above-described
process by taking the impression of the matrix in the soft prepared
rubber or gutta percha compound before it is vulcanized, and vulcanize
the same while it is in contact with the matrix instead of using the
sheets of finished "vulcanite." This soft compound is by means of
calendar rolls or other pressing mechanism spread in sheets or plates
of the desired thickness and is then placed upon the matrix. The
rubber or other material and matrix together are then secured between
two iron or other metal plates and placed in a heater or vulcanizer
and heated. I prefer to subject them for from two to three hours to
a temperature of about three hundred or three hundred and fifty
degrees Fahrenheit, but I do not confine myself to such numbers of
hours or degrees of heat as either may be varied without materially
affecting the result.
I prefer to employ the first of the two processes
herein described when it is desirable to produce the stereotypes quickly,
but when the saving of time is not an object the second process is
preferable.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Rowe Wilson in the Great Seal Patent
Office on the 7th January 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
ROWE WILSON, of Birmingham, in the County of Warwick, India-rubber
Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of July, in the year
of our Lord One thousand eight hundred and sixty-eight, in the
thirty-second year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said George Rowe Wilson, Her
special licence that I, the said George Rowe Wilson, my executors,
administrators, and assigns, or such others as I, the said George Rowe
Wilson, 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 "IMPROVEMENTS IN STEREOTYPE PLATES," upon the condition (amongst
others) that I, the said George Rowe Wilson, my executors or adminis-
trators, 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 I, the said George Rowe Wilson, do hereby
declare the nature of my said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement:-
The said Invention relates to stereotypes formed of vulcanized india-
rubber or gutta percha, or a compound of both substances, and consists
chiefly in the novel modes or processes employed to produce the im-
pressions in or upon the india-rubber or other material. The said
impressions are produced either upon the finished vulcanized sheets

page_text: or in the soft compound of which such sheets are formed, the curing
or vulcanizing being in the latter case afterwards effected by the usual
means. The rubber or other material and the matrix are clamped
together and subjected to heat. After cooling the vulcanized plato
is removed from the matrix and is ready for use.
According to one method of practising my Invention I take a sheet
of hard prepared india-rubber, such as is commonly known as "vulcanite,"
or a sheet of prepared vulcanized gutta percha, or a sheet of the two
substances combined, and soften the same by placing upon it a heated
metal plate. The matrix or mould from which I desire to obtain the
stereotype is then placed upon the softened rubber or other substance.
Behind the matrix I place another plate of iron or other metal. These
two plates with the rubber and matrix between them, as above described,
are then by means of screws or other suitable means clamped or bound
together, and allowed to remain so till they are cold. By this means
an exact and perfect copy of the matrix is obtained upon the surface
of the vulcanized plate. The metal plates may then be unfastened and
the stereotype removed from the matrix. I vary the above-described
process by taking the impression of the matrix in the soft prepared
rubber or gutta percha compound before it is vulcanized and vulcanize
the same while it is in contact with the matrix instead of using the
sheets of finished "vulcanite." This soft compound is by means of
calender rolls or other pressing mechanism spread in sheets or plates
of the desired thickness, and is then placed upon the matrix. The
rubber or other material and matrix together are then secured between
two iron or other metal plates and placed in a heater or vulcanizer
and heated. I prefer to subject them from two to three hours to a
temperature of about three hundred or three hundred and fifty degrees
Fahrenheit, but I do not confine myself to such numbers of hours or
degrees of heat as either may be varied without materially affecting the
result. I prefer to employ the first of the two processes herein des-
cribed when it is desirable to produce the stereotypes quickly, but when
the saving of time is not an object the second process is preferable.
Having thus described my said Invention, and shewn how the same
may be conveniently and advantageously carried into practice I claim,
producing the impression of the stereotype matrix upon a sheet of
prepared or partially prepared india-rubber or gatta percha, or compound

page_text: of the same, by placing the said matrix and sheet between metal plates
and applying heat and pressure thereto, substantially as set forth.
In witness whereof, I, the said George Rowe Wilson, have here-
unto set my hand and seal, this Fifth day of January, in
the year of our Lord One thousand eight hundred and sixty-nine.
GEORGE ROWE WILSON. (L.S.)