Improvements in the Production of Zinc or other Metal Blocks for Printing Purposes.
Year: 1896

page_text: Date of Application, 28th Jan., 1896
Complete Specification Left, 27th Oct., 1896-Accepted, 19th Dec.. 1896
PROVISIONAL SPECIFICATION.
Improvements in the Production of Zinc or other Metal Blocks for
Printing Purposes.
I, CARL HENTSCHEL of 182 and 183 Flect Street in the City of London,
Photo Engraver, do hereby declare the nature of this invention to be as follows:-
Hitherto it has been customary in the production of blocks from pencil
drawings by photography for printing purposes to use a screen either ruled or
grained in order to obtain during the photographic process the necessary gradua-
tious of shade on the picture; the zinc or other metal plate employed has had a
smooth or plain surface.
Now the object of my invention is to dispense with the use of a screen and with
this object I employ instead of a smooth zinc or other metal plate a plate having a
grained surface produced in any suitable manner. I produce a photographic
negative in the ordinary way but without the use of a screen and after this
photograph has been printed on to the grained metal plate this is submitted to the
usual treatments. The result is a zinc or metal block having all the facsimile
appearance of the pencil sketch or drawing; this being due to the original
graining.
Dated this 28th day of January 1896.
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.
Improvements in the Production of Zinc or other Metal Blocks for
Printing Purposes.
1, CARL HENTSCHEL of 182 and 183 Fleet Street in the City of London,
Photo Engraver, 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 :-
Hitherto it has been customary in the production of metal blocks from pencil,
crayon or charcoal drawings by photography for printing purposes to use a glass
screen either ruled or grained in order to obtain during the photographic process
the necessary graduations of shade on the picture, the zinc or other metal plate
employed having had a smooth or polished surface.
Now the object of my invention is to dispense with the use of a grained or
ruled screen and with this object I employ instead of a smooth zinc or other metal
plate a plate having a very finely grained surface produced in any suitable manner
the plate being then sensitized in the usual way. I produce a photographic
negative in the ordinary way of the drawing to be reproduced but without the
use of a screen as heretofore. I then print this photograph on to the grained

page_text: metal plate after which this is submitted to the usual treatments practised in
zincography. The result is a zinc or metal block having all the appearance of
the pencil crayon or charcoal sketch or drawing; this being due to the original
graining on the plate.
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 process for the production of metal blocks from pencil, crayon
or charcoal drawings by photography for printing purposes substantially as
hereinbefore described.
2. In the production of metal blocks from pencil, crayon or charcoal drawings
by photography for printing purposes, the use of a finely grained metal plate,
substantially as hereinbefore described aud for the purpose specified.
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.