A Polychrome Printing Process
Year: 1897

page_text: Date of Application, 7th May, 1897-Accepted, 26th June, 1897
CUMIINI MCIFICATION.
A Polychrome Printing Process."
I, PETER JENSEN of 77 Chancery Lane, London, W.C. Chartered Patent
Agent, do hereby declare the nature of this invention, a communication to me.
from abroad by the Firm of Aug. Schweig & Co. of Weisswasser o/L Oberlausitz,
Germany, Porcelain Manufacturers, and in what manner the same is to be
performed to be particularly described and ascertained in and by the following.
statement:-
This invention consists in a polychrome printing process whereby it becomes-
possible by one pull through the press to render all the colours and shading of the
drawing in contradistinction to the known polychrome process, which requires a
special plate for each colour and whereby the several colours are successively put
upon the paper to produce a complete picture; the sheet has by that process to be
pulled as many times as it is to contain colours, and the plates have to be changed"
each time; nor can this process show any shading, which is a great defect.
According to the present invention the design with all its contours and shadings.
is first drawn on the etching plate. When the plate has been exposed long enough
to the etching liquid the latter is run off and the shadings are etched a second time
while the other parts of the design are covered. After such general etching of the
shadings the darker shadings are etched for the third time and the very darkest
then for the fourth time. Although ordinarily three or four gradations are
sufficient, yet the number of same is by no means limited and may in case of
delicate designs be increased as desired.
The plate having thus been finished and the covering material cleaned off the
colours may now be put on, and the paper when pulled will show all the colours
and all the shadings.
Although this process may be generally applied to in all industries requiring
polychrome printing yet it is of very especial value for pictures on glass and
porcelain. For such purposes the ordinary polychrome printing has hitherto been
available, and also the process whereby the contours of the design were transferred
by means of prints from the etching plate, but the several colours and shadings had
10 be painted on by hand, a work which involves not only a considerable time, but
also a not inconsiderable. degree of skill the consequence being somewhat high
prices of the articles so painted. But by means of the new process the whole
design with all its colours and shadings is by one printing from the etching plate
transferred to the article to be painted, thus doing away with the necessity for
subsequent hand painting.
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondents and in what manner the
same is to be performed I declare that what I claim is :-
1. A polychrome printing process consisting in the repeated treatments of the
shading portions of the design on the plate with etching liquid so that the same are
etched to varying depths, whereupon after removal of the ground covering the
several colours are put upon the plate, the prints from which will contain not
merely the contours and principal colours but also the several shadings of the
design substantially as set forth.

page_text: 2. The application of the prints made by the process firstly claimed for transfer
-upon glass and porcelain of the colours and shadings of the design.
Dated this Seventh day of May 1897.
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.