CERTAIN IMPROVEMENTS IN THE PREPARATION OF GUTTA PERCHA AND CAOUTCHOUC, AND IN THE APPLICATION THEREOF
Year: 1851

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, STEPHEN
MOULTON, of Bradford, in the County of Wilts, India Rubber Manufacturer,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Fourteenth day of August, in the fifteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Stephen Moulton, Her especial license, full power, sole privilege and
authority, that I, the said Stephen Moulton, my exors, admors, and assigns,
and such others as I, the said Stephen Moulton, my exors, admors, or
assigns, should at any time agree with, and no others, from time to time and
at all times during the term of years therein mentioned, should and lawfully
might make, use, exercise, and vend, within England, Wales, and the Town
of Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN THE
PREPARATION OF GUTTA PERCHA AND CAOUTCHOUC, AND IN THE APPLICATION
THEREOF;" in which said Letters Patent is contained a proviso obliging me, the
said Stephen Moulton, by an instrument in writing under my hand and seal,
particularly to describe and ascertain the nature of my said Invention, and in
what manner the same is to be performed, and to cause the same to be
inrolled in Her Majesty's High Court of Chancery within six calendar months

page_text: next and immediately after the date of the said in part recited Letters Patent,
as in and by the same, reference being thereunto had, will more fully and
at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Stephen Moulton, do hereby declare that the nature of the said Invention, and
the manner in which the same is to be performed, are particularly described
and ascertained in and by the following statement thereof (that is to say):-
The Invention consists in the discovery of a new combination of several
materials by which I produce a new and valuable compound. It is a fact
well known to persons acquainted with the native gutta percha, that it is very
materially affected by the change of climate, that it becomes rigid when
exposed to a low degree, and soft when exposed to a high degree of tempera-
ture, that it does not at any time possess any elastic properties, and that these
liabilities to change with tho climate, and its non-elastic qualities, prevent the
native gutta percha from being applied to a great variety of useful purposes.
The nature of my Invention or discovery consists in obviating these dis-
advantages by combining gutta percha with a mixture of sulphite or hypo-
sulphite of lead or zinc and the artificial sulphuret of lead or zinc, and sub-
mitting the compound to the action of a high degree of heat, by which I
produce a material which I call cured gutta percha, possessing the quality of
elasticity, unaffected by the changes of temperature, and resisting the solvents
of the native gum. To enable others skilled in the art to make and use my
Invention, I now proceed to describe the manner and mode of making the
compound above mentioned:-After the gutta percha has been cleansed from
its impurities, I take one or more pounds weight of it as can conveniently
be ground or mixed at a time, and add from two ounces to half a
pound of the sulphite or hypo-sulphite of lead or zinc and the artificial
sulphuret of lead or zinc, in about equal proportions of each, to which I add
from two to twelve ounces of Paris white or chalk powdered, which is ground
between heated rollers and treated in the same manner as set forth in my
Patent of the Eighth February, One thousand eight hundred and forty-seven,
for Improvements in treating Caoutchouc with other Materials to produce
Elastic and Impermeable Compounds," and to which for this part of the
mode of making my said Invention I now particularly refer.
My Invention further consists in combining one part of gutta percha with
one part of caoutchouc, or, as the case may require, a greater or less proportion
of either the one or the other, with the sulphite or hypo-sulphite of lead or
zinc and artificial sulphuret of lead or zinc, in about equal proportions of each.
To one pound weight of the compound of gutta percha and caoutchouc I use

page_text: from two to six ounces of the before-mentioned materials, to which, as a dryer,
I add from two to twelve ounces of powdered Paris white or chalk, and
prepare and treat this compound in every respect the same as I do gutta percha
alone. I use the same machinery, and expose it to the same degree of heat,
producing a fabric equally as valuable for many purposes, rather more elastic,
but not as capable of so perfectly resisting the action of oils as when gutta percha
alone is used. If I want to produce a hard cured gutta percha composition,
or gutta percha and caoutchouc composition, similar to horn or ivory, I add
from two to twelve ounces of calcined magnesia to the pound of gutta percha
compound, alone or combined with caoutchouc, and treat it in all respects the
same as when the magnesia is not used. After the gutta percha, or the gutta
percha and caoutchouc, has been ground and mixed, the compound is still
liable to be effected by changes of temperature and the action of solvents, the
same as in their natural state; to prevent which, the compound, whether in the
form of coated cloth, sheet gum moulded, or any other article, should be
placed in a room or vessel as near air-tight as possible, and subjected to steam
or dry heat of from two hundred and fifty to three hundred and fifty degrees
of Fahrenheit. The time required for thus curing the compound will vary
from two to ten hours or thereabouts, according to its thickness and the
quantity of goods put in a mass together for this part of the process of the
manufacture. After the goods have undergone the curing as above, (if properly
done), they will be found not only impermeable to wet, but extremely tenacious,
possessing the elastic property of the cured caoutchouc, and also unaffected by
the changes of temperature.
What I claim as my Invention or discovery, and desire to secure by Letters
Patent, is the use, in combination with gutta percha alone, or with gutta
percha and caoutchouc, of the acids of sulphur of a lower degree of
oxygenation than sulphuric acid in combination with suitable bases, but I
prefer a hypo-sulphite which can be used alone or in combination with the
salts of the acids of sulphur, or with the sulphurets, substantially as above
described.
I also claim the use of the artificial sulphurets of lead and zinc in
combination with Paris white or chalk, used with the gutta percha alone or
gutta percha and caoutchouc, or with a salt of a lower degree of oxygenation
than a sulphate, and artificial sulphuret of lead or zinc, substantially as above
described.
And, further, I claim the treating of gutta percha, either alone or with
caoutchouc, by combining therewith calcined and carbonate of magnesia and

page_text: hypo-sulphite of lead and the artificial sulphuret of lead or zinc, and subjecting
it to a high degree of temperature, as herein described.
In witness whereof, I, the said Stephen Moulton, have hereunto set my
hand and seal, this Thirteenth day of February, in the year of our
Lord One thousand eight hundred and fifty-two.