IMPROVEMENTS IN THE PRODUCTION OF PRINTING SURFACES
Year: 1853

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn
Fields, in the County of Middlesex, and of Glasgow, North
Britain, Gentleman, for the Invention of "IMPROVEMENTS IN
THE PRODUCTION OF PRINTING SURFACES."-A communication from
Auguste Feldetrappe, of Paris, in the Empire of France,
Engraver.
Sealed the 25th May 1854, and dated the 25th November 1853.
PROVISIONAL SPECIFICATION left by the said John Henry
Johnson at the Office of the Commissioners of Patents, with his
Petition, on the 25th November 1853.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
of Middlesex, and of Glasgow, North Britain, Gentleman, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE
PRODUCTION OF PRINTING SURFACES," communicated to me by Auguste
Feldetrappe, of Paris, in the Empire of France, Engraver, to be as
follows:-
This Invention relates to the production of printing surfaces on
cylinders employed in the printing of textile and other fabrics, and

page_text: convenient means.
consists in tracing out the outline of the pattern, either in small dots or
in diagonal lines ruled close together. These contours are engraved on
the cylinder, either by an impressing roller, or by hand, or any other
The cylinder is then varnished, and its whole
length and circumference is traversed by parallel diagonal lines, which
raise the varnish and enter slightly into the metal. These lines are
traced by steel or diamond point, and run in an opposite direction to
the diagonal lines forming the outline of the design. In this state the
roller is again coated with varnish over the parts to be left as a pattern,
and is subjected to the action of the acid. The ground of the pattern is
also formed by an impressing roller, diagonally grooved or otherwise
cut. This roller is rolled slowly over the varnished surface of the
cylinder, and exposes the metal by penetrating the varnish in diagonal
lines at a certain angle, according to the inclination given to the
engraving or pressing roller. The parts which have been outlined are
again covered with varnish, and the roller placed in acid or " aqua
fortis." In patterns or designs which may be commencing without the
aid of a die or mould, the following process is adopted :-The surface to
be treated, whether flat or cylindrical, is coated with an even layer of
varnish and is traversed, as before described, by diagonal or other
parallel lines. The pattern is conveyed to the surface by an exact
tracing or transfer, and the parts to be left white are coated, when the
surface is submitted to the action of acid. In this way the different
tints are produced to the proper depths required. This system may be
adopted with success with the first light tints, but for the darker tints a
more effective system is adopted. The first light tints being "bitten,"
the roller is freed from varnish and again coated, and the unwrought
parts are then traced by lines, but in a different direction, the number
of such lines being diminished or augmented, and the depth of the
same regulated, according to the tint required. After being cut or
grooved in the ordinary manner, the parts to be left uncut may be
recoated, and the darker portions of the pattern only are left to the
action of the acid. The light tints are then recoated, and the double
ones are submitted to the biting process. To improve the appearance
of the pattern and prevent the light tint from clouding, the cylinder is

page_text: entirely varnished and lined in an opposite direction to the engraved
lines. The white parts are again covered, and the whole is again sub-
mitted to the action of the acid for a short time. For patterns of many
tints or shades, the white portions are traced out and cleared, and the
impressing roller tempered and applied to the cylinder. The cylinder
is then recoated with varnish, and the biting process proceeded with to
the required depth for the second shade, and so on for the rest.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 25th May 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of Glasgow, North Britain, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fifth day of November, in the
year of our Lord One thousand eight hundred and fifty-three, in the
seventeenth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said John Henry Johnson, Her
special license that I, the said John Henry Johnson, my executors,
administrators, and assigns, or such others as I, the said John Henry
Johnson, my executors, administrators, or assigns, should at any
time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Inven-
tion for "IMPROVEMENTS IN THE PRODUCTION OF PRINTING SURFACES," com-
municated to me from Auguste Feldtrappe, of Paris, in the Empire of
France, Engraver, upon the condition (amongst others) that I, the said
John Henry Johnson, by an instrument in writing under my hand and
seal, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six

page_text: calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said John Henry Johnson, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement, that is to say:-
The said Invention relates to an improved system or mode of
engraving the printing cylinders and plates employed in calico and
other printing, and to the production of the rollers for impressing or
cutting such cylinders. In ground patterns, which are generally
made by a steel cutting roller or cutting machine, instead of unin-
terrupted lines or contours, such as those which are obliged to be
made when the ground of a pattern on the roller is to be grooved,
the said ground is engraved in the following manner:-The contour
of the pattern of which the ground is to be engraved is composed
of sufficiently fine dots, or in diagonal lines close together. These
contours may be engraved on the cylinder either by a cutting roller,
by manual labor, or by 'machinery. After this operation, the cylinder
is varnished with varnish dissolved in spirits of turpentine, and its
surface is traversed the entire length and circumference by parallel
diagonal lines, the cutter or marker entering the metal to a certain
extent and raising the varnish along its course. These lines are made
by the cutting machine with the aid of a steel or diamond point. If
the contours of the patterns have been made in diagonal lines running
from left to right downwards, the lines traced on the surface of the
roller should run in an opposite direction, or from right to left down-
wards. The figures or pattern of the roller thus lined are coated with
varnish, the ground of the roller being bitten with the acid. By using
the contours just described, that is to say, such contours which are
formed by diagonal lines, the ground of the pattern may be engraved
with a cutting roller diagonally grooved or otherwise formed. It is
adjusted in size to the length of the line to be made on the surface of
the cylinder. This cutting roller is fitted in two bearings in the position
usually occupied by the diamond holder; it is inclined more or less
according to the slope or angle to be given to the lines. This roller is

page_text: passed lightly over the surface of the cylinder which has been previously
varnished, so as to leave the metal uncovered, the varnish being taken
up by the teeth of the roller. An unengraved portion, sufficiently large
to carry the scraper or "doctor," is left between each cut of the cutting
roller, as in grounds made by machinery. The parts which have been
outlined are then recoated with varnish, and the cylinder placed in aqua
fortis. In rolling the cutting roller over the cylinder, the advantage of
the outlines in dots or pricks over those in simplé lines is, that with the
first the cutting roller being supported on the contours, it enters the
métal of the cylinder regularly, an advantage which is not attained
when the cutting roller is rolled over outlines or contours formed by
uninterrupted lines; in all patterns which may be commenced without
the aid. of the cutting roller, the cylinder plate or cutting roller to be
engraved is first coated with an even layer of varnish, and then
traversed, as described, by parallel lines, either in a transverse,
diagonal, or circular direction, and traced also with a steel or diamond
point. This being completed, the pattern is indicated on the cylinder
by means of a tracing, or exact transfer on tracing paper, of all the
details and all the tints of the pattern to be engraved. The pattern
being traced, the parts to be left white are coated over, and the
cylinder afterwards placed in acid to bite it, according to the depth
which it is requisite to give the second tint. The other tints are effected
in the same manner. This system may be adopted with success with
the first light tints, but for the darkest colors a system which gives
more life, is adopted. When the first light tints have been bitten in, the
roller is cleaned and again varnished, and parallel lines are again
traced, but in another direction, over the whole cylinder; the number
and depth of the lines being increased or diminished to obtain the said
dark tints. By that means a greater intensity in the colors is obtained,
with a more decided difference between the half tints and the dark
tints. The cylinder being thus prepared, the light tints are recoated
with varnish, and the dark tints left to be bitten by the acid to the
required depth. To give to the pattern an even and regular tint and
prevent the light tints from clouding, when the cylinder is engraved,
it is varnished and lined or ruled in an opposite direction to that of the

page_text: engraving, the lines being kept much closer. As a sharp steel or
diamond point cannot be used for this purpose, they are replaced by a
steel tool or diamond having an angular form thus, in order that it
may easily pass over the hollows of the engraving. The white parts are
again covered with the cylinder, again submitted to the action of the
acid for a few moments only. For producing patterns of several
shades or tints, which are usually engraved by the steel cutting roller or
other means, those which are formed on a rough ground, either in dots,
or diagonal or other lines, have the white portions of the pattern first
traced and then bitten away. This roller is then tempered and applied
on to the cylinder. The engraving being finished, the projecting parts
of the surface of the cylinder are filled up with varnish, and the parts
which are to be preserved in the lightest tints, recoated entirely. The
biting is then proceeded with until the required depth is obtained for
the second shade, and the same process continued with the others. But
if the pattern contains large dark surfaces, the process just indicated is
adopted; that is to say, the engraved roller is cleaned and re-varnished
entirely, so as to fill the hollows with varnish; it is afterwards ruled
diagonally in either direction, according to the requirement of the
design, and the operation carried on as above described. This means
affords facility of increasing the design by shadows as much as desired,
as a completely different aspect may be obtained by changing the
position of the shadows in each, and facility is also afforded of making
as many repetitions of the cutting roller as may be required, which is
not possible by the means at present employed, where the process is
limited by certain dimensions.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that I do not con-
fine or restrict myself to the precise details or arrangements which I
have had occasion to describe or refer to, as many variations
may be
made therefrom without deviating from the principles or main features
of the said Invention. But what I consider to be novel and original,
and therefore claim as the Invention secured to me by the herein-
before in part recited Letters Patent, is,-

page_text: First, the production of different tints on printing cylinders, plates,
or cutting rollers by lines made, as herein-before described.
Second, the mode of forming the contours of patterns in dots or
diagonal lines, in the manner and for the purpose herein-before
described.
Third, the system or mode of engraving by "aqua fortis," as herein-
before described.
Fourth, the system or mode of increasing the size of a pattern by
varying the order of the tints in the repetitions, as herein-before
described.
In witness whereof, I, the said John Henry Johnson, have here-
unto set my hand and seal, the Twenty-fifth day of May, One
thousand eight hundred and fifty-four.
J. HENRY JOHNSON. (L.S.)