An Improved Process of Printing in Colours.
Year: 1891

page_text: Date of Application, 24th Feb., 1891-Accepted, 11th Apr., 1891
COMPLETE SPECIFICATION.
An Improved Process of Printing in Colours.
We WILLIAM SCHUMACHER, Lithographer and Louis CHRISTIAN RAEGENER,
Lawyer, both of 280 Broadway in the City, County and State of New York in the
United States of America, do hereby declare the nature of this invention, and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention relates to an improved process of printing in colours in such a
manner that the well known character of a water-colour painting is closely imitated
while ordinary lithographic stones or other printing surfaces can be employed for
this purpose, and the invention consists of a process of printing in colours by the
following successive steps. Firstly, producing the different tints by means of a
brush and lithographic ink on a hard unimpressible transfer sheet of suitable
material. Secondly, transferring said wash tints by transfer sheets to lithographic
stones or other printing surfaces having a grained surface. And lastly, printing
from said stones in different colours so as to reproduce the original painting.
In carrying out our invention a number of thin transfer sheets of a suitable hard
unimpressible substance such as celluloid or other material are either placed one
after the other over the water colour or other painting or on the impression used
as a key for said painting that is to be reproduced in colour, care being taken that
the proper register of the transfer sheets with the original painting is retained.
A transfer sheet is used for each colour of the original painting, while the transfer
sheet is placed in position over the original painting or on the key of said painting,
the special tint being produced on the same by means of a brush or lithographic
ink or crayon or by means of a rub tint or in any other suitable manner, so that a
so-called wash tint is produced the different portions of which are graduated in
proportion to the depth of colour in the original painting. When opaque transfer
sheets are used it is necessary to transfer the outlines of the different tints on said
sheets by any of the methods known to lithographers, such as for instance by
making a key from the original which is offset on the transfer sheet on which the
wash tints are produced by freely following the original which is placed before the
eyes of the artist.
When as many transfer sheets as there are colours in the original painting are
thus produced the wash tints in the same are transferred by the sheets to as many
separate lithographic stones zinc plates or other printing surfaces which are pro-
vided with a suitable grain preparatory to receiving the wash tints from the
transfer sheets. After the transfer of the wash tints is made the printing surfaces
are coated with a layer of a solution of gum and after drying washed off, the
printing surfaces being then rolled up in the usual manner with transfer ink. The
stones are next prepared with gum and acid like a crayon drawing. The wash tints
are thereby broken up into small dots on the points of the raised portion of the
grain so that a practical printing plate for the lithographic press or for the relief
printing press after a relief etching of the grain plate is made is obtained. The
tints on the printing surfaces are an exact reproduction of the wash tints on the
transfer sheets being denser at the heavier parts and thinner at the lighter parts.
The different colours are then printed in register from the printing surfaces until
a picture is obtained in which the characteristic features and tints of the original
painting are faithfully reproduced. In addition to the wash tints employed
graining or stipple effects may be added to the transfer sheets and transferred with
the wash tints to the printing surfaces or they may be produced on said printing
surfaces in the usual manner.

page_text: Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what we
claim is :-
The process herein described of printing in colours which consists in reproducing
the different colours of the picture in wash tints by means of lithographic ink or
crayon on the surface of as many separate transfer sheets as there are colours to be
printed, then transferring the several wash tints from the transfer sheets to separate
printing stones or plates having grained surfaces and then printing the different'
colours from said printing surfaces in register to correspond with the colours of the
original picture substantially as described.
Dated this 20th day of February 1891
POPPLEWELL & Co.,
17 & 18, Southampton Buildings, London, W.C.,
Agents for the Applicants.