An Improvement in India Rubber Compounds and in Gutta Percha Compounds.
Year: 1897

page_text: Date of Application, 5th May, 1897
Complete Specification Left, 3rd Nov., 1897-Accepted 11th Dec. 1897
Date of Application, 5th May, 1897
Complete Specification Left, 3rd Nov., 1897-Accepted 11th Dec.
1897
PROVISIONAL SPECIFICATION.
An Improvement in India Rubber Compounds and in Gutta Percha
Compounds.
We EDMOND GARNIER engineer of 309 Camberwell New Road London SE and,
SAMUEL JAMES PRESCOTT, jeweller, of 33 Church St. Camberwell, London SE do
hereby declare the nature of this invention to be as follows:-
The incorporation of suitably treated pumice stone to india rubber goods, india
ubber compounds gutta percha compounds or vulcanite goods generally.
Dated this fourth day of May 1897
EDMOND GARNIER.
SAMUEL JAMES PRESCOTT.
An Improvement in India Rubber Compounds, and in Gutta Percha
Compounds.
We, EDMOND GARNIER of 309 Camberwell New Road, London S.E and SAMUEL,
JAMES, PRESCOTT, of 33 Church Street Camberwell London S.E. Engineer and
Jeweller respectively 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:-
Our invention relates to improvements in India rubber compounds, and gutta
percha compounds and consists mainly in the employment of very finely ground
pumice stone, in substitution for chalk, carbonate of magnesia, sand, and other sub-
stances hitherto employed for loading or reducing the quality of such compounds.
We have discovered that the said finely ground pumice powder or pumice flour
when mixed in suitable and varying proportions, with pure rubber, or gutta-percha
01 similar gums
or both, with which it readily assimilates, yields. a
compound of great tenacity at less cost of production, and possessing the
properties of being almost odourless and non-injurious to health, and when prepared in
such proportions that the pumice powder is in excess, and the whole adaptable for
use in the production of substitutes for floor-cloth, wall-paper, and the like, is
non-inflammable, and of a much lower specific gravity, than the articles for which it
is substituted.
Our invention lies in the discovery that pumice powder may be advantageously
employed as a substitute for, and in the adulteration of rubber or gutta-percha,
and is independent of the proportions used and of the manner of curing or vulcaniz-

page_text: ing the resultant compound, as such proportions may vary indefinitely according
to the uses to which the said compound may be adapted, that is to say, the greater
the proportion of rubber or gutta percha, or other gums employed the richer and
more costly would be the resultant compound, while a larger proportion of added
pumice-powder would produce a less costly and poorer compound, and the pro-
portion of added sulphur, and the process of vulcanization or curing would depend
upon the degree of elasticity, or density, or hardness which the resultant material
is desired to assume, such process of vulcanization or curing forming no part of
our invention, as this may be carried out in the usual way and by the well known
means, therefore, we wish it understood that the process of manufacture hereinafter
stated is given merely by way of example,
The pumice stone is first. ground to a very fine powder or flour, and carefully
sifted or screened to remove all non-pulveriferous particles therefrom, and to this
we add a suitable proportion of flowers of sulphur, also carefully sifted or screened,
the whole being then carefully and thoroughly mixed together in a suitable vessel,
and may be colored or tinted as desired by the addition of suitable coloring matters.
The rubber, gutta or other gums employed would be passed between the heated
or other rollers of a suitable mill in the usual way, until in a proper state of
malleability or plasticity, when the desired proportion of pumice and sulphur
powder would be gradually added thereto, and again and again passed between
the same or other rollers, until thoroughly incorporated therewith, when the whole
may be rolled out into sheets of any desired thickness, by the means of suitable
rollers, which may be such as to impart a figure, or pattern upon either or both
faces of the said sheets, the same being then cured or vulcanized to the extent
desired in the usual way. Or the said compound while in a state of plasticity or
dough may be laid or spread upon canvas, cloth, or other fabric or material in
sheet form, and passed between patterned or other rollers, so that the said com-
pound may be forced in to the substance of the said fabric, and be incorporated
therewith, or merely laid in any desired thickness upon the surface thereof. Or
the said compound may be placed in suitable moulds, or formed into blocks, slabs,
or other shapes, so as to adapt it for the purposes required.
As previously stated, the process of curing or vulcanizing the said compound,
does not form part of our invention, but we may mention that we find a steam
pressure of from. 25 to 35 lbs (about 272° Fahr) a desirable or convenient pressure
and degree of temperature, and that the process may be prolonged for two or more
hours until the desired degree of elasticity or hardness is attained.
Although, as previously mentioned, the proportions of pumice powder and rubber,
or gutta, or other gums employed, may vary indefinitely according to its intended
uses, we may mention that we find in practice, that in rubber compositions we may
employ to one part of rubber as much as six or eight parts of punice powder, and
half a part of sulphur, while in gutta or other gum compounds we may add to one
part of gutta or the like, five or six parts of pumice, and from a quarter to one part
of sulphur.
We find in practice that in compounds where the proportion of pumice, is greatly
in excess of the rubber or gutta, that the said compound may be vulcanized to such
a degree of hardness as to be capable of use in substitution of lithographic stones,
and that compounds in which the pumice is not in excess the same may be used in
substitution of embossed or plain leather, or American cloth for upholstering pur-
poses and the like.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is:
1st. As a new article of manufacture, a compound consisting of a mixture of
finely powdered pumice stone, with rubber, gutta-percha, or similar gums, or mix-
tures thereof, which is subsequently cured or vulcanized substantially as and for
1

page_text: 2nd. In a rubber compound, the combination of rubber and finely powdered
pumice stone in suitable proportions substantially as herein set forth.
3rd. In gutta-percha and other gum compounds, the combination of gutta-percha
or other gums and finely powdered pumice stone in suitable proportions sub-
stantially as herein set forth.
T
1
NL
1007
GEO. THOS. HYDE
1 Broad Street Buildings Liverpool Street London EC
Agents for the Applicants.