IMPROVEMENTS. IN THE MANUFACTURE OR TREATMENT OF GUTTA PERCHA, BEING IMPROVE- .MENTS UPON THE INVENTION SECURED TO HIM BY LETTERS PATENT, DATED THE 20TH DAY OF JULY 1852
Year: 1853

page_text: LETTERS PATENT to Emory Rider, of Coleman Street, in the City
of London, Manufacturer, for the Invention of "IMPROVEMENTS. IN
THE MANUFACTURE OR TREATMENT OF GUTTA PERCHA, BEING IMPROVE-
.MENTS UPON THE INVENTION SECURED TO HIM BY LETTERS PATENT,
DATED THE 20TH DAY OF JULY 1852."-Partly a communication.
PROVISIONAL SPECIFICATION. left by the said Emory Rider at
the Office of the Commissioners of Patents, with his Petition, or
the 18th October 1853..
I, EMORY RIDER, of Coleman Street, in the City of London, Manu-
facturer; do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OR TREATMENT OF GUTTA PERCHA,
BEING IMPROVEMENTS UPON THE INVENTION SECURED TO HIM -BY-LETTERS
PATENT, DATED THE 20TH DAY OF JULY 1852," to be as follows:-
This Invention reiates and has especial reference to certain improve-
ments, already patented by me, which consist in treating gutta percha

page_text: in its raw state by the action of heat, so as to expel the volatizable
ingredients therefrom, and render the same fit for the after processes of
vulcanization. In carrying out the above Invention I have discovered
that I produce a better effect by adding to the raw gutta percha a
small quantity of sulphur or any equivalent of sulphur before subject-
ing the gutta percha to the preliminary heating process; by this means
I find that a lower temperature can be employed in such heating pro-
cess, and the product is more ductile, and has greater tenacity than
when the preliminary heating alone is employed, and the gutta percha
also requires a smaller portion of sulphur in the after vulcanizing
process.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Emory Rider in the Great Seal Patent Office
on the 18th April 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME,
EMORY RIDER, of Coleman Street, in the City of London, Manufacturer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of October, 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 successors,
give and grant unto me, the said Emory Rider, Her special license that
I, the said Emory Rider, my executors, administrators, and assigns, or
such others as I, the said Emory Rider, 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 Invention for "IMPROVEMENTS IN THE MANUFACTURE
OR TREATMENT OF GUTTA PERCHA, BEING IMPROVEMENTS UPON THE INVENTION
SECURED TO ME BY LETTERS PATENT, DATED THE TWENTIETH DAY OF JULY 1852,"
partly a communication to me from abroad, upon the condition (amongst
others) that I, the said Emory Rider, by an instrument in writing

page_text: 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 calendar months next and immediately after the date.
of the said Letters Patent.
NOW KNOW YE, that I, the said Emory Rider, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by
the following statement, that is to say:
My said Invention relates to certain improvements in treating gutta
percha by the action of heat, so as to expel the volatizable ingredients
therefrom, and render the same fit for the processes of vulcanization,
for which improvements I obtained Letters Patent for England on or
about the Twentieth day of July One thousand eight hundred and fifty-.
two. In carrying out the above-mentioned Invention I have discovered
that I produce a better effect by adding to the raw gutta percha a small
quantity of sulphur, or any equivalent of sulphur, before subjecting the
gutta percha to the preliminary heating process, by which means I find
a lower temperature produces an effect equal to that of a higher
temperature when the gutta percha alone is treated. I have found one
part of sulphur, or the equivalent thereof, added to eighty parts of gutta
percha, when separated from its solid impurities, suitable for effecting
this purpose. The sulphur, or hyposulphite of lead or zinc, or the
artificial sulphuret of lead or other equivalent of sulphur, should be
thoroughly mixed or incorporated with the gutta percha by passing the
gum and the dryers repeatedly between metallic rollers heated to a
temperature sufficient to make the gutta percha very soft and easily
kneaded or worked; the mode of effecting this I have found in practice
most beneficial is by the employment of a machine in which the rollers
work at different degrees of speed, and produce a tearing or grinding
action, of considerable importance in working the material. The
incorporated material having been ground is then placed in a strong
metal vessel or vessels; care being taken however that the material does
not occupy more than one third of the capacity of the vessels, so as to
leave due allowance for the swelling or expansion of the material when

page_text: under the action of heat. The material is then exposed to a tempera-
ture of about two hundred and ninety degrees Fahrenheit for a space
of about three hours, soi as to. give a nearly uniform temperature
throughout the mass but the actual time depends to a great extént
upon the nature of the gum, the degree of: heat employed, and the
quantity and state of aggregation.of.the material at the time the heating
is commenced. The heat employed.may be either by the action of steam
or hot air, but I prefer the employment. of steam, by which I am
enabled to subject the gum under treatment to a greater pressure, and
to obtain a more regular degrecisofeheat than by any other means.
The gutta percha, having undergone..this preliminary heating, may be
employed in manufactures of various kind,: as. for belting, shoe, soles,
coating 'telegraphic wires; and other purposes..to which the gum is now
usually applied in: England, the gum in this state being an improvement
upon that in ordinary use, insomuch that it will not oxydize; or the gum
may be prepared for the vulcanizing operation, the main object of this
Invention, by being "combined with sulphur, hyposulphite of lead or
zine, artificial sulphurett of lead, and the pigments and dryers neces-
sary to produce the particular articles required, which having been
accomplished, the material may be worked and manufactured into any
form or shape, and-carried through the process of-vulcanization, as-well
known in working caoutchouc, the material produced. being permanently
elastic, and not liable to be changed by the action of cold or heat.
Having now described and particularly ascertained the nature of my
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 confine
or restrict myself to the precise details or arrangements which I have
liad occasion. to describe or refer to, as many variations may be made
therefrom without deviating from the principles or main features of my
said Invention; but what I consider to be novel and original, and there-
fore claim as the Invention secured. to me by the herein-before in part
recited Letters Patent, is,
The mode of treating gutta percha by the addition thereto of a very
small quantity of sulphur, or an equivalent thereof, prior to the expo-
süre of the same to the action of heat, for the purpose of expelling the

page_text: volatizable ingredients therefrom, as secured to me by a former grant
of Letters Patent.
In witness whereof, I, the said Emory Rider, have hereunto set
my hand and seal, the Eighteenth day of April, One thousand
eight hundred and fifty-four.
EMORY RIDER. (L.S.)