Improvements in or relating to Hand Stamps.
Year: 1891

page_text: Date of Application, 3rd July, 1891
Complete Specification Left, 3rd May, 1892-Accepted, 4th June, 1892
PROVISIONAL SPECIFICATION.
Improvements in or relating to Hand Stamps.
JOHN WILLIAM Beaufort 25 Colmore Row Birmingham Photographer do
hereby declare the nature of this invention to be as follows:-
:-
A hand stamp the face of which is composed of rubber, gutta percha, or some
similar substance. The face (or relief) being obtained from a cast from a bichro-
mate gelatine positive and made to print a range of tones from white to black with
specially prepared ink, for printing on any smooth material.
Dated this 2nd day of Lulu 1901
JNO. W. BEAUFORT.
COMPLETE SPECIFICATION.
Improvements in or relating to Hand Stamps.
I, JOHN WILLIAM BEAUFORT, of 25 Colmore Row, in the City of Birmingham,
Photographer, 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 an improvement in stamps of india-rubber or like
substance, and its purpose is to prepare a stamp from a photograph of any object
which shall by inking and stamping accurately reproduce the photograph by
printing on paper or other surface.
In carrying my invention into effect, I prepare on glass or other suitable surface
a gelatine film containing bichromate of potash, and I print on this film from a
negative. The light so acts on the gelatine and bichromate, that where exposed
to its influence, the gelatine becomes insoluble in water. I then dissolve off,-
preferably in a hot water bath, the parts of the gelatine which have not been acted
on by the light, which so remain soluble. This produces a raised image of the
object depicted on the negative, in which tone is caused by the partial solubility of
the portions more feebly acted on by the light. The lights and shades of the
original photograph are thus accurately followed by the relief image on the gelatine
film, some portions of which, the lightest parts of the negative or the darkest parts
of the original, stand up in relief more than others.
I varnish the plate to which the gelatine film is to be applied with collodion,
before transferring the gelatine film; this protects the raised part and keeps it
together. The gelatine film after printing is stripped with its collodion backing
and I damp the gelatine film to cause it to swell. oil over the film to prevent
plaster of Paris from sticking, and I pour on, carefully mixed fine plaster of Paris
or other suitable substance in a fluid or semi-fluid state, and this produces a mould
with the raised parts of the gelatine film hollow.
After the plaster of Paris has sufficiently set and dried I remove the plate, and
into the mould so produced I press unvulcanized india-rubber to which preferably
sulphur has been added. I remove the block after solidifying and vulcanize by the
ordinary process by exposure to a sufficient temperature.
It will be readily understood that I may copy in this manner any image, repre-
sentation or drawing on a glass or other surface of transparent or partly transparent
nature, and it is to be remembered that the stamp may be of gutta percha or other
like substance instead of rubber.
The stamp may be inked from a smooth plate and roller, in any well known
manner.

page_text: Referring to the accompanying sheet of drawings which illustrate the application
of my invention―
Figure 1 is a section through a gelatine positive film prepared in the manner I
have indicated in which raised parts are shown at a, b, c. The section is taken on
the line y, y on the plan Figure 2.
Figure 2 is a plan showing a photograph and the points a, b, c correspond to the
points similarly marked on Figure -1.
Figure 3 shows the same section of the film as in Figure 1, but here a trough is
formed so as to pour on plaster to obtain a hollow cast.
Figure 4 is a section of the plaster cast obtained as illustrated at Figure 3, and
here also a trough is formed and semi-fluid rubber is shown as being pressed into
the hollows in the said plaster cast to form a positive rubber stamp.
It will be readily understood that the gelatine film d may be formed in any
well known manner, but I prefer to form it on a collodion film so as to hold it
together and allow it to be transferred if required. The plaster caste is formed
by pouring on as shown in Figure 3 and it is removed from the gelatine film d and
transferred to a firm backing f, the film being preferably previously oiled to
prevent the plaster from sticking. A trough is formed if required with fand a
mass of semi-fluid or soft warm rubber unvulcanized but having sulphur incor-
porated throughout it is pressed into the hollows a, b, c corresponding to the
elevations a, b. a. The soft rubber is indicated at g (Figure 4) and it is pressed
into the mould by a plate as or other suitable means. The rubber is allowed to
set and become cold in pressed contact with the mould, and it is then removed and
soinetimes vulcanized. In this manner a rubber stamp is forined which may be
used in any usual manner with the specially prepared ink used with such stamps.
The stamp may be inked by a pad, but it is preferred to ink it from a glass or
other smooth plate.
Copies of photographs may be thus impressed by stamping on paper or other
material in the manner common to ordinary rubber stamps.
Gutta percha or other similar material may be used for the stamp following the
same process as with rubber.
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 of manufacturing reproducing and printing stamps from
photographic negatives substantially as and for the purposes hereinbefore described
and as set forth in the accompanying drawings.
2. A hand stamp composed of rubber or other suitable material prepared from a
cast taken from a gelatine positive film substantially as and for the purposes herein-
before described and illustrated in the accompanying drawings.
Dated this 2nd day of Now 1800
MARKS & CLERK,
13, Temple Street, Birmingham, Agents for the Applicant.