IMPROVEMENTS IN THE MANUFACTURE OF INDIA RUBBER."
Year: 1881

page_text: LETTERS PATENT to Isaac Livermore, of College Hill, Cannon Street, in the
City of London, for an Invention of "IMPROVEMENTS IN THE MANUFACTURE
OF INDIA RUBBER."
PROVISIONAL SPECIFICATION left by the said Isaac Livermore at the Office
of the Commissioners of Patents on the 15th November 1881.
ISAAC LIVERMORE, of College Hill, Cannon Street, in the City of London.
"IMPROVEMENTS IN THE MANUFACTURE OF INDIA RUBBER."
The Invention has for its object primarily improvements in the manufacture of
that class of india rubber known as "fine cut sheet rubber."
Heretofore such class of rubber has been made in different colors, but each sheet
being of one uniform color, such as black, red, green, and so on.
Now according to my Invention I manufacture such class of sheet rubber of two
or more colors worked up so as to cause the colors to produce a marbled, mottled,
or variegated appearance.
In carrying my Invention into effect I first thoroughly masticate the rubber
into masses, each of a single color, until they are in the condition in which they are
usually pressed into blocks in readiness for the cutting operation. Instead however
of pressing the masses at this stage, I leave, say, the black mass in the masticator,
and I cut up a portion of the other colored mass or masses into comparatively small
pleces, which I distribute over the black mass left in the masticator, gradually
turning over such mass until the desired proportion of colored rubber has been
added to it; the compound mass is then masticated, and is turned about or changed
in position and cut, and the sides turned in towards the middle and again
masticated until the desired effect is produced; care must however be exercised to
prevent this second mastication being carried too far, as, were such the case, a mass
would be produced of uniform or nearly uniform tint.
After this second mastication has been carried to the determined point, the parti-
colored mass is removed from the masticator and pressed, after which it is cut into
fine cut sheet rubber in the manner well understood. If desired however the pressed
parti-colored block can be cut into various sized blocks and shapes for various
purposes.
It will be evident that the method of procedure may be somewhat modified
without departing from the peculiar character of my Invention.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Isaac Livermore in the Great Seal Patent Office on the 15th May
1882.
_ISAAC LIVERMORE, of College Hill, Cannon Street, in the City of London.
"IMPROVEMENTS IN THE MANUFACTURE OF INDIA RUBBER."
The Invention has for its object primarily improvements in the manufacture of
that class of india rubber known as "fine cut sheet rubber."
Heretofore such class of rubber has been made in different colours, but each sheet
being of one uniform colour, such as black, red, green, and so on.
Now according to my Invention I manufacture such class of sheet rubber of two
or more colours worked up so as to cause the colours to produce a marbled, mottled,
or variegated appearance.
In carrying my Invention into effect I first thoroughly masticate the rubber into
masses, each of a single colour, until they are in the condition in which they are
usually pressed into blocks in readiness for the cutting operation. Instead however
of pressing the masses at this stage, I leave, say, 150 pounds of the black mass in
the masticator, and I take from another masticator and cut up a portion consisting,
say, of about 15 pounds of the other coloured mass or masses into comparatively
small pieces, which I distribute over the black mass left in the masticator,
gradually turning over such mass until the desired-proportion of coloured-rubber
has been added to it; the compound mass is then masticated and is turned about
or changed in position and cut, and the sides turned in towards the middle and
again masticated until the desired effect is produced; care must however be
exercised to prevent this second mastication being carried too far, as, were such the
case, a mass would be produced of uniform or nearly uniform tint.
I would observe that the colouring rubber must be taken hot from a masticator
and introduced direct into the body of the material while it is still hot from
mastication, in order to produce good results.
After this second mastication has been carried to the determined point, the
parti-coloured mass is removed from the masticator and pressed, after which it is
cut into "fine cut sheet rubber" in the manner well understood.
If desired however the pressed or unpressed parti-coloured block or mass can be
cut or formed into various sized blocks and shapes for various purposes.
It will be evident that different coloured rubbers may be combined in various
proportions, and that the method of procedure may be somewhat modified without
departing from the peculiar character of my Invention.
Having thus described the nature of the said Invention and the mode in which
the same is carried into effect, I would have it understood that what I claim is,―
The improvements in the manufacture of india rubber hereinbefore described.
In witness whereof, I, the said Isaac Livermore, have hereunto set my
hand and seal, this Twelfth day of May, in the year of our Lord One
thousand eight hundred and eighty two.
1. LIVERMORE, (L.S.)