A Process for the Production of Incised or Raised Designs on Metal Plates or Rollers to be used in the Potting, Calico-printing, Kamptulicon, Electro-type, or other Trades or Manufactures in which Engraved or Etched Rollers are in Use or may be used.
Year: 1894

page_text: Date of Application, 7th Aug., 1894
Complete Specification Left, 7th May, 1895-Accepted, 3rd Aug., 1895
PROVISIONAL SPECIFICATION.
A Process for the Production of Incised or Raised Designs on Metal
Plates or Rollers to be used in the Potting, Calico-printing,
Kamptulicon, Electro-type, or other Trades or Manufactures in
which Engraved or Etched Rollers are in Use or may be used.
1 JOHN PILSON HEWITT Artist Designer and Etcher 117 Campbell Road
Stoke-on Trent Staffordshire do hereby declare the nature of this invention to be
as follows:-
Improvements in the method of producing incised or raised designs on copper-
steel or other metal plates or rollers to be used in the potting (under which head is
comprised all ceramic industries-including earthenware china terra-cotta and all
other pottery productions-whether made from "plastic" clay (as toilet ware and
the like or cast in "slip" clay as certain vases-thin china and the like or from
"dust" clay by pressure as tiles) calico-printing kamptulicon-electro-type or
other trades or manufactures in which engraved or etched rollers are in use or may
be used so that the metal plates or rollers so incised or raised-which now cannot
be produced except at great cost of time and money-may by this process be
produced in about one-fourth the time, and at one half the present cost.
By my process all metal plates or rollers used in the trades and manufactures
hereinbefore inentioned may be produced at a very great saving in cost of time
and money-for whereas by the present process a manufacturer has not only to pay
very large sums of money for such engraved or etched plates or rollers-but to
wait a considerable time (such time depending upon the amount of work in the
design) after giving out the work to be engraved or etched-before he is able to
get it from the engraver-for the present method of producing an engraved design
is to have the design transferred to the metal plate or roller and then to cut away
by hand the portion forming the design-that is presuming the design is required
incised-if it is for "block-printing" the design is left and the surrounding portion
is cut away. Supposing the design is to be etched--then the metal is first coated
with a resist
or ground of prepared wax (asphaltum, Burgundy pitch &
bees-wax mixed is the best) aud the design then transferred-the wax scratched
away and the metal exposed where required-then acid or acid & water in
combination to suit the requirements of the design are poured on and allowed to
remain until the necessary depth is obtained. This of course is a long and tedious
method and I claim to be able to shorten it very greatly in the following way-By
my invention and processes-
The design to be reproduced on the metal plates or rollers should be made in line
or line and dot or stipple-i.e., not painted (for the first process) and then a
photograph taken from it. The metal plate or roller having been previously
covered with a coat of sensitized gelatine-gum or glue-is then printed from the
photograph-when printed wash well in cold water and the design will wash off the
metal then pour alcohol over it and allow to dry-after which place it on a stove
and heat it until it turns brown in colour, but do not go much above 550° F.
Then etch or bite in with a mordant which will not touch the ground remaining
on the plate (alkali's, bi-carbonate of potash, perchloride of iron) all mixed with

page_text: water as required. If greater depth is wanted when above has been done, then
take a roller (leather or composition) and roll a wax ground over the plate or
roller, taking care not to fill up the lines or holes-and afterwards etch or bite in
with any of the above mordauts or with a mordant composed of nitric acid and
water, or, if for copper plates or rollers-nitros neid & water.
Or it can be done by taking the design or picture or photograph to be re-
produced and photographing it through a lined screen which gives it the effect of
having been produced by lines. This photograph must then be printed on a metal
plate which has been coated once or twice with a solution made as follows-
Take the whites of two eggs & beat up well in two ounces of water-when
thoroughly beaten up, add two ounces of glue (fish glue preferably) let them be
well mixed, and having ready another mixture made of about 120 grains of
ammonium bichromate and two ounces of water-add the ammon: bichrom: solu-
tion gradually to the egg mixture, and keep stirring while doing so-let this stand
for a few hours, then filter well before using. When printed put the metal plate
or roller in water and soak it well, then wash well, and then pour alcohol over it-
when dry burn in as in the first method and afterwards allow it to cool very
gradually then hite in with a solution of perchloride of iron and water-the
strength of the solution and duration of biting or etching must be determined by
the technical requirements of the design and the experience of the workman.
The difficulty of applying the above processes to rollers has hitherto been the
impossibility of photographing (cheaply and commercially) on cylindrical surfaces
this difficulty I have overcome (as far as necessary for the before mentioned
trade requirements) in the following manner and by my own invention―
Instead of using glass for the negative to be taken from the design, picture,
drawing or photograph, use very thin sensitized gelatine films & photograph on
them exactly as for glass & through lined screens (if the subject is not specially
drawn in lines, stipples and dots) then when the roller is prepared or coated with
the mixtures given above, take the gelatine film on which the subject is photo-
graphed and bend it round the roller until it fits exactly-after which fix the ends
of the roller in sluts or supports and revolve it, allowing the light to fall upon it,
then it will print as equally as is absolutely necessary for the requirements of the
trades before mentioned.
When printed treat in every way as before stated, excepting that in biting in or
etching a roller, a portion of the roller had better be allowed to touch the mordant
and the roller rotated during the time necessary for the etching or biting in-and
in burning in, the roller must he turned continuously so that the heat is distributed
equally.
Having now described the particulars, and ascertained the nature of my said
invention and the method or processes by which metal plates or rollers can be
produced in a very much cheaper and quicker manner than they are at present
being produced (for use in the before mentioned trades & manufactures) and
have by practical experience and careful tests accomplished this which I consider
an important step towards creating a new industry, and by which manufacturers
can (at no greater cost than they are paying now) bring out at least twice as many
new designs as they are at present doing and I believe that this method o
process has never before been applied to metal rollers or plates in any of the before
mentioned trades or manufactures.
Dated this 4th due of Avert 180
JOHN PILSON HEWITT,
Inventor.

page_text: COMPLETE SPECIFICATION.
A Process for the Production of Incised or Raised Designs on Metal
Plates or Rollers to be used in the Potting, Calico-printing,
Kamptulicon, Electro-type, or other Trades or Manufactures in
which Engraved or Etched Rollers are in Use or may be used.
1, JOHN PILSON HEWITT Artist Designer aud Etcher 117 Campbell Road
Stoke-on-Trent Staffordshire 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 :-
Improvements in the method of producing incised or raised designs on copper-steel
or other metal plates or rollers, to be used in the potting (under which head is
comprised all ceramic industries including earthenware, china terra cotta &c. and
all other pottery productions, whether made from plastic clay as toilet ware &c.
or cast in slip clay as certain vases or thin china or from dust by pressure as tiles)
calico-printing kamptulicon, electro-type or other trades in which engraved or
etched rollers are in use or may be used so that the metal plates or rollers so
incised or raised which now cannot be produced except at great cost of time &
money may by this process be produced in about one fourth the time and at less
than the present cost.
And I claim that-
By my process all metal plates or rollers used in the trades and manufactures
hereinbefore mentioned may be produced at a very great saving in cost of time
and money. For, whereas, by the present process a manufacturer has not only to
pay very large sums of money for such engraved or etched plates or rollers, but
to wait a cousiderable time (such time depending upon the amount of work in the
design) after giving out the work to be engraved or etched, before he is able to
get it from the engraver, for the present method of producing an engraved desigu
is to have the design transferred to the metal plate or roller and then to cut away
by hand the portion forming the design-that is presuming the design is required
incised if it is for "block" printing the design is left, and the surrounding
portion is cut away. Supposing the design is to be etched, then the metal is first
coated with a "resist or ground of prepared wax (asphaltum or Burgundy-pitch
and bees-wax mixed is considered the best) and the design then transferred, the
wax scratched away and the metal exposed where required, then acid, or acid and
water in combination to suit the requirements of the design is poured on and
allowed to remain until the necessary depth is obtained. This of course is a long
and tedious method and I claim to be able to shorten it very much in the following
way, by my invention and process :-
"
The design to be reproduced on the metal plates or rollers must be made in
Indian iuk, or some other strong colour, then photographed through a lined screen,
which gives it the effect of having been produced by lines. This photograph, after
developement, must then be printed on to a metal plate which has been previously
coated with a film made as follows:-
:-
Take the whites of two eggs and beat up well together in two ounces of water,
when thoroughly beaten up add two ounces of glue (fish-glue preferable) let them
be well mixed, and having ready another mixture made of about 120 grains of
ammonium bichromate, and two ounces of water, add the ammonium bichromate
solution gradually to the egg mixture and keep stirring while doing so. Let this
stand for a few hours then filter well before using. When printed upon from the
photograph negative of the design put the metal plate or roller in water and
thoroughly wash until the design is washed off, afterwards pour alcohol over the
remaining portions of the film. When dry place it on a stove and heat until it

page_text: turns brown in colour, but do not let the heat exceed 550° F. Then etch or bite
in with a mordant which will not touch the remaining ground on the plate, for this
purpose perchloride of iron is used. The strength of the mordant, and the duration
of etching must be determined by the technical requirements of the design and the
experience of the workman. If greater depth is required when the above has been
done, take a roller (either leather or composition) and roll a wax ground over the
plate or roller, taking care not to fill up the lines or holes, and afterwards etch with
the above mordant, or with nitric acid diluted with water, or if for copper plates,
dilute nitrous acid may be used.
The difficulty of applying the above process to rollers has hitherto been the
impossibility of photographing (cheaply or commercially) on cylindrical surfaces,
this difficulty I claim to have overcome (as far as necessary for the before mentioned
trade requirements) in the following manner and by my own invention-Instead
of using glass for the negative to be taken from the design, picture, drawing, or
photograph, use very thin sensitized gelatine films and photograph on them exactly
as for glass, and through lined screens, then, after the roller has been prepared or
coated with the mixture given above take the gelatine film on which the subject
has been photographed and bend it round the roller until it fits exactly, after
which fix the ends of the roller in slots or supports and revolve it, allowing the
light to fall upon it, then it will print as equally as is absolutely necessary for the
requirements of the trades before mentioned. When printed treat in every way as
described for the plates, excepting that in etching a roller a portion of it had better
be allowed to touch the mordant and the roller rotated during the time necessary
for for the etching, and in burning in the roller must be turned continuously so that
the heat is equally distributed.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:
—
1. I claim that this new method of producing metal plates or rollers for these
trades and manufactures has never been used before.
2. I claim that I have originated this method for the before mentioned trades
and manufactures, and by careful tests and experiments have demonstrated its
practicability.
3. I claim that for reproduction of artists designs for the said industrial purposes
it is much superior to any other system at present being practised.
Dated this 6th day of May 1895.
JOHN PILSON HEWITT,
Inventor.