IMPROVE- MENTS IN THE CONSTRUCTION, MANUFACTURE, AND REPRODUCTION OF STAMPS AND OTHER PRINTING SURFACES IN RELIEF
Year: 1864

page_text: LETTERS PATENT to Alfred Leighton, of 'No. 9, Buckingham' Street,
Strand, in the County of Middlesex, for the Invention of "IMPROVE-
MENTS IN THE CONSTRUCTION, MANUFACTURE, AND REPRODUCTION OF STAMPS
AND OTHER PRINTING SURFACES IN RELIEF.""
:
Sealed the 7th October 1864, and dated the 21st April 1864.
PROVISIONAL SPECIFICATION left by the said Alfred Leighton at
the Office of the Commissioners of Patents, with his Petition, on the
21st April 1864..
I, ALFRED LEIGHTON, of No. 9, Buckingham Street, Strand, in the County
ofi Middlesex,i do hereby declare the nature of the Invention for "IMPROVE-'
MENTS IN THE CONSTRUCTION, MANUFACTURE, AND REPRODUCTION OF STAMPS 'AND'
OTHER PRINTING SURFACES IN RELIEF," to be as follows:-
E
This. Invention has for its object improvements in the construction, manu-
facture, and reproduction of stamps and other printing "surfaces in' relief.
Stamps to be used by hand for printing letters and words, or it may be designs
on papers, packages, and similar articles, are now commonly made with metal
printing surfaces fixed to a suitable handle, but such stamps when used to
mark wood or hard substance produce very indifferent impressions unless great
care be taken in using them, and if the surface to be printed upon is rough or

page_text: uneven, the production of a good impression with a metal stamp becomes
impossible.
Now according to my Invention I construct stamps with a printing surface
of elastic material raised in relief with the letters or words required to be
printed upon it, as in a metal stamp. The elastic printing surface is mounted
and attached to a handle such as is ordinarily employed, and usually, in order
to increase the elasticity and decrease the liability of the printing surface to
spread with the pressure used in printing, I groove the back of the surface or
block, or make elevations and depressions therein, so that the back of the
surface or block may spread with the pressure, and relieve and equalize the
pressure on the face. The material I prefer to employ for making the elastic
printing surfaces or blocks is india-rubber, and it is vulcanized in the process
of producing the surface or block, this however may be varied; but whatever
the material employed, care must be taken that the ink used with the surface
is of such a nature as not to injure the elastic substance of which the surface
or block is made.
In manufacturing the elastic printing surfaces and blocks I employ a
matrix or mould, and cast or press into it the elastic material or compound;
if the material or compound be, as I prefer, a mixture of india-rubber with
sulphur, after pressing the compound into the matrix or mould, I apply heat to
it whilst still there until the compound becomes vulcanized. The matrix or
mould I usually employ, is obtained from a form of type set up in the ordinary
manner, each type carrying or having formed on it a letter or sign, or it
may be a portion of a design, and I make the matrix in metal, plaster, or
other hard material from the form in any convenient manner, of which
there are many well known; from this matrix I obtain elastic printing
surfaces or blocks as already described. In place of a form of type, wood-
cuts or other surface printing blocks may be used in producing the matrix.
It will be seen that. the elastic printing surface. or block produced is in each
case a reproduction of the printing surface which is employed in making its
matrix.
:
Elastic printing surfaces or blocks of Jarger size may be, similarly.con-
structed and manufactured; and they may when mounted on wooden or other
blocks or rollers, or otherwise, be worked in a printing press to print hard and
rigid surfaces.

page_text: SPECIFICATION, in. pursuance of the conditions of the Letters Patent, filed..
by the said Alfred Leighton in the Great Seal. Patent Office on the
21st October, 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED
LEIGHTON, of No. 9, Buckingham Street, Strand, in the County of Middlesex,'
send; greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of April, in the year of 'our Lord'
One thousand eight hundred and sixty-four, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Alfred Leighton, Her special licence that I, the said
Alfred Leighton, my executors, administrators, and assigns; or such others'
as I; the said Alfred Leighton, my executors, administrators, and 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 Invention' for '
"IMPROVEMENTS IN THE CONSTRUCTION, MANUFACTURE AND REPRODUCTION OF STAMPS
AND OTHER PRINTING SURFACES IN RELIEF," upon the condition (amongst others)
that I the said Alfred Leighton, my executors or administrators, by a
an instru-
ment in writing under my, or their, or one of their hands and seals, sliould
particularly describe and ascertain the nature of the said Invention; aud
in what manner the same was to be performed; and cause the same to be
filed in the Great Seal Patent Office within six calendar months next and'
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Alfred Leighton; do hereby
declare the nature of the said Invention, and in what manner the same is.
to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:―
'
This-Invention has for its object improvements in the construction; manu-
facture and reproduction of stamps and other printing surfaces in relief."
Stamps to be used by hand' for printing letters and words, or it may be designs -
on papers, packages, and similar articles, are now commonly made with metal
printing surfaces fixed to a suitable handle, but such stamps when used to
mark wood or hard substance-produce very indifferent impressions, unless
great care. be taken in using them, and if the surface to be printed upon is
rough or uneven, the production of a good impression with a metal stamp.
becomes impossible.

page_text: Now my Invention consists in manufacturing printing surfaces, whether for
stamps or for other arrangements of printing apparatus or machinery, by
forming the printing surfaces of india-rubber compound, and vulcanizing
them in moulds, the surfaces printed from in each case being in relief. And
in order to increase the elasticity and decrease the liability of the printing
surface to spread with the pressure used in printing, I groove the back of the
printing surface or block, or make elevations and depressions thereon, so that
the back of the surface or block may give way or spread with the pressure,
and thus relieve and equalize the pressure on the face. The material I
employ for making the elastic printing surfaces or blocks is india-rubber and
sulphur suitable for undergoing the process of vulcanization, and the compound
is, as above stated, vulcanized in the moulds used in the process of producing:
the surface or block. It is preferred, but it is not essential, that no foreign
matter other than sulphur should be mixed with the india-rubber, unless it be,
to color the same.
:
In manufacturing the elastic printing surfaces and blocks I employ by
preference a metallic or plaster of Paris matrix or mould, and I press into it.
the compound of india-rubber and sulphur. After pressing the compound into
the matrix or mould, I apply at the back of the composition a metal or plaster
plate, and press the same on to the composition, by which means elevations
and depressions will be produced to the back of the elastic block by reason
of the plate being formed with parallel and uniform grooves or ridges thereon.
I then apply heat to the moulded mass whilst still held pressed in the mould,
and until the compound becomes vulcanized. The proportion of a suitable
compound of india-rubber, and the process of vulcanizing the same, being well
understood, it is not necessary to describe them here. The mould I usually
employ is of metal, and is by preference obtained from a form of type set up
in the ordinary manner, though the mould may be otherwise produced. I
make the mould by first obtaining a sunk copy in gutta percha, wax, or other
suitable material. From this copy I obtain another copy in relief in plaster
of Paris, and then a sunk matrix in metal, steriotype metal being, preferred,
and from this matrix I obtain vulcanized elastic printing surfaces or blocks as
already described. In place of a form of type, woodcuts or other surface
printing blocks may be used in producing a matrix or mould suitable to be,
subjected to the heat requisite for the process of vulcanizing. It will be seen
that the elastic printing surface or block produced is in each case (unless the
mould be produced by other means) a reproduction of the printing surface
which is employed in making its matrix or mould, having on its back]
Corrugations or undulations.

page_text: The elastic blocks having their printing surfaces in relief when for hand or
other stamps are to be mounted and used in a similar manner to that in
which other surface printing blocks have heretofore been used; elastic blocks
of larger sizes may be mounted on wooden or other blocks, or on rollers, and
may be used in printing machines or presses.
In witness whereof, I, the said Alfred Leighton, have hereunto set my
hand and seal, this Eighth day of October, in the year of our Lord One
thousand eight hundred and sixty-four.
ALFRED LEIGHTON. (L.S.)