Improvements in the Production of Matrices for Casting Printing Plates.
Year: 1889

page_text: Date of Application, 19th Nov., 1889
Complete Specification Left, 9th Aug., 1890-Accepted, 27th Sept., 1890
PROVISIONAL SPECIFICATION.
Improvements in the Production of Matrices for Casting Printing
Plates.
I, ALBERT SAUVÉE, of 22 Parliament Street, Westminster, in the County of
Middlesex, Civil Engineer, do hereby declare the nature of this invention to be as
follows :-
My invention relates to improvements in the production of matrices for casting
printing plates either flat, or curved for rotary web presses.
My invention consists in the preparation of a flong composed essentially of paper
and plaster of Paris to obtain a matrix or mould sufficiently pliable to be bent for
casting curved printing plates.
A suitable method of carrying my invention into effect consists in taking a sheet
of rather stout unsized paper, which is first damped and then laid upon a flat surface,
such as a slab of marble or a lithographic stone. Upon the opposite edges of this
sheet of paper a thin strip of zinc is laid.
A suitable plaster (such as plaster of Paris) is then mixed with water to a con-
sistency to enable it to be easily applied to the surface of the paper, when a bar
resting upon the two side strips of zinc is drawn over its upper surface, so as to
remove any excess and leave a layer of plaster of the desired depth and with a uniform
and sinooth surface.
This sheet of unsized paper and layer of plaster of Paris form the flong and to get
the matrix the plaster face of this flong is carefully applied to the type or engraved
surface to be reproduced, one or more sheets of unsized paper are added to the paper
backing according to the thickness of matrix required and pressure applied on the
top by any suitable means.
The matrix while still on the surface to be reproduced is then dried in a suitable
press, and when dry is removed and the printing plates (either flat or curved)
reproduced in the usual way.
The engraved or other surface to be reproduced is suitably treated (as for example,
with French chalk in the case of engraved plates, or with oil in the case of type) so
as to prevent the plaster adhering when it is applied thereto.
Dated this 19th day of November 1889
ALBERT SAUVÉE.
COMPLETE SPECIFICATION.
Improvements in the Production of Matrices for Casting Printing
Plates.
I, ALBERT SAUVÉE, of 22 Parliament Street, Westminster, in the County of
Middlesex, Civil Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
My invention relates to improvements in the production of matrices for casting
printing plates either flat, or curved for rotary web presses.
My invention consists in the preparation of a flong composed essentially of paper
and plaster of Paris to obtain a matrix or mould sufficiently pliable to be bent for
casting curved printing plates.
A suitable method of carrying my invention into effect consists in taking a sheet
of rather stout unsized paper, which is first damped and then laid upon a flat surface,
such as a slab of marble or a lithographic stone. Upon the opposite edges of this
sheet of paper a thin strip of zinc is laid.

page_text: A suitable plaster (such as plaster of Paris) is then mixed with water to a con-
sistency to enable it to be easily applied to the surface of the paper, when a bar resting
upon the two side strips of zinc is drawn over its upper surface, so as to remove any
excess and leave a layer of plaster of the desired depth and with a uniform and smooth
surface.
This sheet of unsized paper and layer of plaster of Paris form the flong, and to get
the matrix the plaster face of this flong is carefully applied to the type or engraved
surface to be reproduced; one or more sheets of unsized paper are added to the paper
backing according to the thickness of matrix required, and pressure applied on the
top by any suitable means.
The matrix while still on the surface to be reproduced is then dried in a suitable
press, and when dry is removed and the printing plates (either flat or curved)
reproduced in the usual way. The paper backing and the thin layer of plaster of
Paris constituting the matrix can be bent to any desired curvature without injury,
when desired to produce curved printing plates.
The engraved or other surface to be reproduced is suitably treated (as for example,
with French chalk in the case of angraved plates, or with oil in the case of type) so
as to prevent the plaster adhering when it is applied thereto.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The improved method of producing matrices for casting printing plates con-
sisting in the use of a flong formed by spreading a uniform layer of plaster, preferably
plaster of Paris, in a plastic condition upon a backing of paper, and applying such
plaster while still plastic under pressure to the type or engraved surface to be
reproduced, substantially as specified.
2. The improved flong for producing matrices for casting printing plates, con-
sisting of a backing-of-paper to which a uniform layer of plaster, preferably plaster
of Paris, is applied, substantially as specified.
Dated this 8th day of August 1800