IMPROVEMENTS IN THE PRODUCTION OF STEREOTYPE PLATES, CASTS, AND FORMS
Year: 1876

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN
THE PRODUCTION OF STEREOTYPE PLATES, CASTS, AND FORMS." A communica-
tion from abroad by Theodor Ruth, of Frankfort-on-the-Maine, in the Empire
of Germany.
Sealed the 30th June 1876, and dated the 15th January 1876.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 15th January 1876.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN THE PRODUCTION OF STEREOTYPE PLATES, CASTS,
AND FORMS." A communication to me from abroad by Theodor Ruth, of Frankfort-
on-the-Maine, in the Empire of Germany.
This Invention has for its object the production of stereotype plates cast from
matrices and forms of all kinds at a cheaper rate and of a more durable quality than
can be obtained by the ordinary methods.
The plates, rolls, cylinders, and the like are not only applicable for printing upon
paper, but also for printing or impressing metal, porcelain, glass, wood, stone, and
other surfaces, whether hard or soft, plain or otherwise. They may be used either
for ordinary book printing or for producing ornaments of all kinds upon any
required surface.
In carrying out this Invention an elastic mass is first produced by melting
together glue, gelatine, and glycerine, in about the under-mentioned proportions,
which however may be varied as required, vizt. :-
Glue
Gelatine }
say about 50 parts by weight.
Glycerine, say about 50 parts by weight.
In some cases there may be added to the above material a small quantity of
bichromate of potash.
Froin the letters, engravings, and the like there is first taken an impression with
prepared bibulous paper or with the above composition; this mould, after having
been covered with oil, is placed upon a plain metal plate surrounder with borders
or edges of the height of the mould.
When the mould has been thoroughly dried, the melted composition above
[Price 4d.]

page_text: mentioned is poured upon it, after which it is covered or weighted with a plate of
any suitable material, lined with linen or other similar substance for the purpose of
ensuring an equal thickness of the form, and rendering the back side perfectly
smooth. After a short time the mass will become thoroughly cooled, and the form
or cast can be removed from the mould, when it will be ready for use. When these 5
forms or casts are to be exposed to the action of heat, say for example, warm water
or other liquid, the mass is rendered insoluble by the addition of a small quantity
of bichromate of potash and exposing it to light,
.
AND FORMS.
A communication to nie from abroad by Incodor, OF FUNION
on-the-Main, in the Empire of Germany.
The said Invention has for its object the production of stereotype plates, casts
from matrices, and forms of all kinds at a cheaper rate, and of a more durable
quality than can be obtained by the ordinary methods.
The plates, rolls, cylinders, and the like are applicable not only for printing upon
paper, but also for printing metal, porcelain, glass, wood, stone, and other surfaces,
whether hard or soft, plain or otherwise. They may be used either for ordinary
book printing, or for producing ornaments of all kinds upon any required surface.
In carrying out this Invention an elastic mass is first produced by melting
together glue, gelatine, and glycerine, in about the undermentioned proportions,
which however may be varied as required, vizt. :-
Glue
}
Gelatine say
about 50 parts by weight.
Glycerine, say about 50 parts by weight.
In some cases thero may be added to the abovo mixture a small quantity of
bichromate of potash.
From the letters, engravings, and the like there is first taken an impression with
prepared bibulous paper, or with the above composition; this mould, after having
been covered with oil, is placed upon a plain metal plate surrounded with borders
or edges of the height of the mould.
When the mould has been thoroughly dried the melted composition above
mentioned is poured upon it, after which it is covered or weighted with a plate of
any suitable material, lined with linen or other similar substance for the purpose of
ensuring an equal thickness of the form, and rendering the back side perfectly
smooth. After a short time the mass will become thoroughly cooled, and the form
or cast can be removed from the mould, when it will be ready for use. When these
forms or casts are to be exposed to the action of heat, say for example, of warm
water or other liquid, the mass is rendered insoluble by the addition of a small
quantity of bichromate of potash and exposing it to light.
By means of this Invention the following advantages are obtained, vizt. :-
Rapid production of forms and casts of matrices.
Economy, both in first cost and from the small amount of waste. The mass may
also be reutilized (when bichromate of potash has notbeen employed) by melting it
with the addition, if necessary, of a small further quantity of the composition to
compensate for loss.
Exact reproduction of the desired object.
Printing by rollers and cylinders, less power required than in the ordinary
manner.

page_text: Having now described and particularly ascertained the nature of the said Inven-
tion, and the manner in which the same is or may be used or carried into effect, I
would observe in conclusion that what I consider to be novel and original, and
therefore claim as the Invention secured to me by the herein-before in part recited
Letters Patent is, the production of elastic plates, casts, and forms by a melting
process, and their employment, substantially as and for the purposes herein-before
described.
In witness whereof, I, the said John Henry Johnson, have to this my Speci-
fication set my hand and seal, this Thirtieth day of June, One thousand
eight hundred and seventy-six.
J. HENRY JOHNSON. (L.S.)