Improvements in the Production of Plates or Blocks for Printing.
Year: 1898

page_text: Date of Application, 8th Nov., 1898-Accepted, 4th Mar., 1899
COMPLETE SPECIFICATION.
Improvements in the Production of Plates or Blocks for Printing.
I, GEORGE RICHARD HILDYARD, of 32, East Dulwich Road, S.E., in the County
of Surrey, Color Printer, 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:-
My invention has reference to the production of plates or blocks for printing,
and consists of an economical mode or process of producing the required designs
upon the plates or blocks, the said mode or process not being limited to the
production of plates or blocks with one special grain as in other processes, but
being capable of producing plates or blocks with designs in full tone and half
tone and with any required number of tones, tints or grains of different textures.
According to my invention I employ a number of screens having respec-
tively grains of different degrees of fineness or texture and I place these screens
in succession in contact with the sensitized plate (preferably of zinc) upon which
the design is to be produced, removing each screen after exposure and then
placing the negative in contact with the sensitized plate and removing the
negative after exposure before introducing the next screen of the series.
"
For example having placed the sensitized plate into position in a photographic
printing frame with the screen of the finest grain in contact with it, I expose
them to diffused light for say from 10 to 20 minutes, with the result that the
grain is reproduced upon the plate; the grain on this screen may consist say
of a series of very fine dots. The screen then removed and the negative is
placed in contact with the plate and exposed for say 5 to 10 minutes. The
negative is then removed and the second screen to give the next tone or tint is
placed in contact with the plate and exposed for say 5 to 10 minutes. This
screen is then removed and the negative replaced in contact with the plate, and so
on until all the screens have been placed in turn in contact with the plate and
exposed; the negative when put in the last time, that is to say, after the removal
of the last screen should be exposed for a considerable length of time say from
1 to 3 hours depending upon the strength of the light. The sensitized plate is
then removed from the frame and washed with running water until the soft
glue of the sensitizing material is washed away. The plate may then be dried
and the design be burnt in by a spirit lamp or otherwise until the resist turns
to a light brown. The plate is then etched in any usual way according to the
fineness and class of work.
Sometimes between the exposures to the successive screens by which different
tints or tones are produced as above explained I apply intermediate or additional
tints or tones or varieties of tints or tones by rubbing, splashing, drawing or
transferring direct upon the sensitized plate, and in such cases the negative may
be put in place and exposed after each of these intermediate operations. Or I
can produce all the required tones or tints by a successive series of transfers,
drawings, splashings or the like upon the sensitized plate, the negative being
put in place and exposed after each of these operations.

page_text: the various screens, as referred to in Claim 3, intermediate or additional tints or
tones or varieties of tints or tones are produced upon the sensitized plate or block
by rubbing, splashing, drawing or transferring directly upon the same.
Dated this 8th day of November 1898.
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London,
Chartered Patent Agents.