Improvements in the Method of and Apparatus or Implements for Use in Obtaining Correct Register in Colour Printing.
Year: 1895

page_text: Date of Application, 13th Nov, 1895
Complete Specification Left, 29th Feb., 1896-Accepted, 18th Apr., 1896
PROVISIONAL SPECIFICATION.
Improvements in the Method of and Apparatus or Implements for
Use in Obtaining Correct Register in Colour Printing.
I COSMAN HENRY COHEN of No. 19 Paul Street Finsbury in the County
of London Printer do hereby declare the nature of this invention to be as
follows:-
'
My invention relates to the operation of obtaining correct register in colour
printing by adjustment of the position in a printing machine of the lithographio
stones or printing blocks or plates from which impressions are successively taken
in the production of a print in two or more inks or pigments or other printing
materials.
The said operation is usually performed by first placing the stone or block
or plate in what is judged to be approximately the required position and then taking
impressions therefrom and altering its position after taking each impression until it
is found that an impression which registers correctly is produced. This method of
proceeding is very troublesome and usually occupies considerable time whereas by
my invention the said operation is easily and quickly effected.
According to my said invention I ascertain the correct position in a printing
machine of a stone or block or plate by placing over it a sheet of transparent or
semi-transparent material (hereinafter termed the "register sheet") having marka
on it in such positions that they will coincide with other marks on the stone or block
or plate when in the correct position in the machine the said register sheet being
supported and retained in a determined position relatively to the bed of the machine
and independently of the stone. In order to provide for the support of the register
sheet as required I prefer to secure it in a frame adapted to be readily placed in
position in the machine and provided with means of engagement with the bed or
other part of the machine or with supports formed in or on or secured to any
convenient part of the machine the arrangement being such that the said frame
when placed on or in the machine may be readily caused to occupy its true
position.
In order to place a stone in register in a printing machine according to my
invention I first place the register sheet in the required position in the machine and
then print or otherwise produce on the said register sheet the mark or marks
by which the register is to be ascertained. I then remove the said register. sheet
and place in the machine the stone which is to be first used and place the register
sheet in position in the machine over the stone and adjust the position of the stone
by means of the ordinary adjusting screws until the marks ou it coincide exactly
with the mark or marks on the register sheet. The stone being then in the
required position the register sheet may be removed and the printing may be
proceeded with as usual after proper adjustinent of the "lay" of the work to be
printed.
A suitable transparent material for the register sheet is celluloid or xylonite but
any other sufficiently transparent material capable of being marked as required may
be used for the said purpose. A convenient arrangement for admitting of ready
insertion of the register sheet in and its removal from the frame consists of bars so
jointed to the sides of the frame that the said sheet may be secured in position by
placing it between the said bars and frame and pressing the said bars thereon.

page_text: The provision for admitting of the said frame being readily placed and supported
in the required position may consist of V shaped brackets secured to the bed
or other part of the machine with which correspondingly shaped feet lugs or
projections on the said frame engage parts of which feet lugs or projections are or
may be adjustable but any other simple arrangement by which the said frame may
be readily supported in a determined position relatively to the bed of the machine
is suitable.
Dated this Thirteenth day of November 1895.
COME DETE DE PUITIATION.
Improvements in the Method of and Apparatus or Implements for
Use in Obtaining Correct Register in Colour Printing.
I, COSMAN HENRY COHEN of No. 19 Paul Street Finsbury in the County of
London, Printer, 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 the operation of obtaining correct register in colour
printing by adjustment of the position in a printing machine of the lithographic
stones or printing blocks or plates from which impressions are successively taken
in the production of a print. in two or more inks or pigments or other printing
materials.
The said operation is usually performed by first placing the stone or block
or plate in what is judged to be approximately the required position and then taking
impressions therefrom and altering its position after taking each impression until it
is found that an impression which registers correctly is produced. This method of
proceeding is very troublesome and usually occupies considerable time whereas by
my invention the said operation is easily and quickly effected.
According to my said invention 1 ascertain the correct position in a printing
machine of a stone or block or plate by placing over it a sheet of transparent or
semi-transparent material (hereinafter termed the "register sheet") having marks
(hereinafter termed "key marks") on it in such positions that they will coincide
with other marks on the stone or block or plate when the said stone or block or
plate is in the correct position in the machine the said register sheet being
supported and retained in a determined position relatively to the bed of the machine
and independently of the stone. In order to provide for the support of the register
sheet as required I prefer to secure it in a frame adapted to be readily placed in
position in the machine and provided with means of engagement with the bed
or other part of the machine or with supports formed in or on or secured to any
convenient part of the machine the arrangement being such that the said frame
when placed on or in the machine may be readily caused to occupy its true
position.
In order to produce the required key marks on the register sheet I proceed as
follows:-1 first place in the machine either a stone expressly prepared for printing
the key marks or one of the prepared stones which is to be used in the production of
the picture or other work to be printed and I apply to the said stone an ink
or pigment of any kind ordinarily used for printing from lithographic stones.
I then place the register sheet over the said stone and in a determined position
relatively to the machine and produce on the underside of the said sheet an
impression of the key marks or design on the said stone by pressing the sheet
thereon. This being done 1 remove the register sheet which is then ready for use
as hereinafter described in severally placing in register in the printing machine each

page_text: of the stones required for use in succession in the execution of the work to be
printed. If the stone used in the marking of the register sheet as described be one
of those to be used in the production of the required picture or printed work
I proceed to print from the stone in the ordinary way before removing it from the
machine but if the eaid stono be one prepared solely for the production of the key
marks on the register sheet I remove the said stone after printing the key marks
on the said sheet and place in the machine the stone which is to be first used in the
printing which stone I adjust to the said position which it is required to occupy in
the printing machine by use of the marked register sheet in the following manner.
I place the register sheet in the determined position relatively to the machine which
is the precise position occupied by the said sheet while the key marks were being
printed on it and I adjust the position of the stone by means of the ordinary
adjusting screws until the key marks on it coincide exactly with or are immediately
under the key marks on the register sheet. The stone being then in position for
accurate printing I remove the register sheet and proceed with the printing from
the said stone as usual. After the required number of impressions have been
obtained from the stone in the machine I remove the said stone and place in the
machine the stone next required for the printing the correct position of which stone
I ascertain by means of the register sheet as described with reference to the stone
previously used and I thus proceed with the several stones required for use until
the picture or printed work is completed. That is to say I ascertain by meaus of
the key marks on the register sheet the correct position of each of the stones
severally and successively placed in the machine and print in the usual way from
each of the several stones as required.
Where blocks or plates are to be printed from I proceed as hereinbefore described
with reference to lithographic stones.
11
It will be understood that my invention has no reference to adjustment of the "lay'
of the work or sheets to be printed which adjustinent must be effected in the
ordinary manner or in any convenient manner before the printing is begun.
A suitable material for the register sheet is the article of commerce known
as transparent celluloid or xylonite but any other sufficiently transparent and
durable material capable of being marked as required may be used for the said
purpose.
A structure or frame suitable for application to a printing machine and for
supporting the register sheet and retaining it in position is hereinafter described
with reference to the accompanying drawings Figure 1 of which is a plan or face
view Figure 2 a side view and Figure 3 an end view of the frame with the register
Bheet secured therein. Figure 4 represents a section taken on the line A, A
Figure 1 and Figure 5 is a face view of a portion of the underside of the frame
with the register sheet therein.. Figure 6 is a transverse section of a portion of the
frame and sheet.
Referring to the said figures a is the register sheet. b, c are the parts of the
frame or support of the register sheet between which the said sheet is secured by
means of screws d, d which bind the said parts bc together thereby holding
or clamping the marginal parts of the sheet a. e e are ribs formed on the part b of
the frame for the purpose of stiffening it and ff are bosses into which the screws d, d
pass. ggare feet or projecting lugs formed on the part of the frame for
engagement with the frame of the bed of the printing machine or with brackets
projections or recesses secured or formed on or in the said part of the machine by
which feet or lugs g g the frame carrying the register sheet is supported in the
required position relatively to the machine which position may be determined in
any convenient manner as for instance by the form or position of the parts of the
machine with which the feet g, g engage.
Although I have illustrated in the accompanying drawings a conveniently formed
structure for supporting the register sheet and retaining it in position it must be
understood that my invention is not restricted to the particular form of structure or
frame illustrated as a structure of any form admitting of the register sheet being

page_text: readily placed and retained in a determined position relatively to the part of the
machine in which the printing stones or blocks or plates are mounted when in use
is suitable for use in working according to my invention.
-
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 I claim :-
-
First. The method hereinbefore described of ascertaining the position of a
printing stone or block or plate in a printing machine while the stone or block or
plate is being adjusted in the machine which method consists in placing a marked'
sheet of transparent or semi-transparent material in a determined position relatively
to the part of the machine in which the stone or block or plate is mounted and
observing the positions of marked portions of the said stone or block or plate
relatively to the positions of the marked portions of the said sheet.
Secondly. An appliance constructed substantially as herein before described and
illustrated in the accompanying drawings for use in ascertaining the correct position
of a printing stone or block or plate in a printing machine that is to say an
appliance consisting essentially of a sheet of transparent or semi-transparent
material provided with a support which is adapted to be readily placed or secured
in a determined' position relatively to the part of the printing machine in which the
printing stone or block or plate is mounted on which sheet the correct position of
the stone or block or plate may be indicated by marks with which other marks on
the stone or block or plate will coincide when it is in position for accurate
printing.
Dated the Twenty-ninth day of February 1896.
W. T. WHITEMAN,
Agent for the Applicant.