IMPROVE- MENTS IN TREATING GUTTA PERCHA
Year: 1854

page_text: LETTERS PATENT to. Henri Jules Duvivier and Henri Chaudet, both of
No. 20, Rue de la Glaciere, in Paris, for the 'Invention of "IMPROVE-
MENTS IN TREATING GUTTA PERCHA."
PROVISIONAL SPECIFICATION left by the said Henri Jules Duvivier
and Henri Chaudet at the Office of the Commissioners of Patents, with
their Petition, on the 23rd November 1854.
We, HENRI JULES DUVIVIER and HENRI CHAUDET, both of No. 20, Rue de la
Glaciere, in Paris, do hereby declare the nature of the Invention for "IMPROVE-
MENTS IN TREATING GUTTA PERCHA " to be as follows:-
This Invention consists in treating gutta percha in the following manner :-
The gutta percha is first divided into shreds and dried at a moderate tempe-
rature; it is then dissolved in purified bisulphide of carbon or other suitable
solvent, then filtered through charcoal, and the bisulphide distilled, off' by
heat; afterwards one (or more) of the following substances is mixed with the
fluid gutta percha
Chloride
Bromide
Iodide
Fluoride
of sulphur ;
Chloride
Bromide'
Iodide
Fluoride
Sulphide
of phosphorous;
.Chloride
*Bromide
Iodide
Fluoride
and the .bichlorides of tin-and antimony.,
of boron
Chloride
Bromide;
Jodide.
Fluoride.
f silicon's
: {
Chloride
Bromide.
Iodide..
Fluoride
of arsenic ;

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henri Jules Duvivier and Henri Chaudet in the Great Seal
Patent Office on the 23rd May 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, HENRI
JULES DUVIVIER and HENRI CHAUDET, both of No. 20, Rue de la Glaciere, in
Paris, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of November, in the year of our
Lord One thousand eight hundred and fifty-four, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us, the
said Henri Jules Duvivier and Henri Chaudet, Her special 'licence that we
the said Henri Jules Duvivier and Henri Chaudet, our executors, administra-
tors, and assigns, or such others as we, the said Henri Jules Duvivier and
Henri Chaudet, our 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 TREATING GUTTA
PERCHA," upon the condition (amongst others) that we, the said Henri Jules
Duvivier and Henri Chaudet, by an instrument in writing under. our hands
and seals, or under the hand and seal of one of us, 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 Henri Chaudet, on behalf of myself
and the said Henri Jules Duvivier, 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):
=
====
"
Our Invention consists in treating gutta 'percha with one or more of the
following substances :-
Chloride
Bromide
Iodide
Fluoride
sulphur ;
Chloride
Bromide
Iodide
Fluoride
Sulphide
phosph
Chloride
Chloride
Chloride
Bromide
Bromide
Iodide.
Iodide
Bromide
Iodide
Fluoride
Fluoride
Fluoride
and the bichlorides of tin and antimony of these substances.
of arsenic;

page_text: We prefer to employ the chloride of sulphur, but results similar to those
obtained by the use of chloride of sulphur may be obtained by the use of any
of the other above-named substances.
And in order that our said Invention may be most fully understood and
readily carried into effect, I will proceed to describe the process which we
prefer to employ for treating gutta percha with these substances.
-The raw gutta percha is divided and torn into shreds by machinery, similar
to that now used for the same purpose in the manufacture of gutta percha, and
these shreds are dried at a gentle heat, that is to say, at a temperature which
will not soften them. When the gutta percha is dried as far as practicable by
this means,
it is dissolved in bisulphide of carbon, the solution being made in a
close vessel, and at a temperature of 86° Fahrenheit. The quantity of bisul-
phide employed should be such as to make a tolerably fluid solution, so that
the heavy impurities may sink, and the lighter impurities rise to the surface..
The solution being perfectly made, is well shaken, and afterwards left to allow
the impurities to separate; and when the solution is perfectly clear, the light
impurities are skimmed from the surface, and the heavy impurities are run
off by a tap at, the bottom of the vessel in which the solution is made. The
clear, solution obtained in this manner may, when great purity is required,, be
filtered through charcoal, otherwise it is immediately transferred to, a still,
which is heated externally by boiling water. In connection with this still
are two condensers, the first of which is kept at such a temperature as to
condense the vapour of the water originally contained in the gutta percha, and
at the same time to allow the, vapour of bisulphide, of carbon to pass on to
the second condenser, there to be condensed. When the whole of the water
and bisulphide, of carbon have been thus separated by distillation, the gutta
percha is removed from the still, and when hard, it is again divided into
small pieces and dissolved in bisulphide of carbon, the quantity of bisulphide
employed being such that a solution of the consistence of syrup is obtained.
This solution should be made in a vessel heated to 86° Fahrenheit, and
closed so as to prevent the escape of the vapour of the bisulphide. When
the solution is complete, from two to fifteen per cent. or more of chloride
of sulphur, diluted with bisulphide of carbon, is added, and well mixed; or
if any of the other substances before mentioned are employed in place
of chloride of sulphur, then from fifteen to fifty per cent. should be
employed.
I would remark, that by this mixture of two per cent. of chloride of

page_text: of gutta percha, a substance is obtained which does not materially differ
from gutta percha in its properties.
When more than two per cent of chloride of sulphur is employed, the com-
pound can be extended when heated to 100° or 120° Fahrenheit, and it
remains extended where cooled, but retakes its original form when again
heated, and at about 212° it agglutinates. When five per cent. of chloride of
sulphur is added, the compound only differs from that just described in being
less softened by heat and in being slightly elastic when cold. When ten
per cent. of chloride of sulphur is added, the properties of the gutta percha
are quite changed, and the compound is unaltered by temperature of 212°.
When above fifteen per cent. of chloride of sulphur is added, the compound
becomes horney and harder as the quantity of chloride of sulphur increases.
Articles may be formed from these compounds by pouring them as soon
as mixed into metal or other suitable moulds, and there allowing them to
set. In the same way we cast blocks of elastic gutta percha, which are
afterwards cut up into pieces of a suitable size for rubbing out pencil
marks. The compounds may also be used for glueing or attaching one
substance to another; they should be applied in a fluid state, and the
two surfaces should be held together until the cement is quite hard; when
attaching leather by this cement the surface of the leather should be made
rough.
Or the above-described process may be varied by first coating the surfaces to
be attached the one to the other with untransformed gutta percha, and then
wetting the surfaces with a solution of two to ten parts of chloride of sulphur
in one hundred parts of bisulphide of carbon, and pressing the surfaces toge-
ther till hard. In a similar manner, articles may be coated with transformed
gutta percha by dipping them first into a syrupy solution of gutta percha in
bisulphide of carbon, and afterwards plunging them into a bath, consisting
of two to ten parts of chloride of sulphur dissolved in one hundred parts
of bichloride-of-carbon. When it is desired that the gutta percha should
penetrate, in place of remaining, as a coating on the surface of the article,
as is sometimes desirable when treating sheets of fabric, wood, leather, and
similar materials, then, in place of simply dipping the article in the solution
of gutta percha, it is allowed to soak therein for twenty-four to thirty-
six hours, and is moderately heated, passed between rollers, and afterwards
dipped into a solution of ten parts of chloride of sulphur in one hundred
parts of bisulphide of carbon. If the articles subjected to these processes
are of such a nature that-they-would-be-damaged by the acid vapours

page_text: formed during the operation, then carbonate of soda should be mixed with
the solution of gutta percha in quantity sufficient to neutralize the acid
formed.
In witness whereof, I, the said Henri Chaudet, have hereunto set my
hand and seal, this Twenty-third day of May, in the year of our Lord
One thousand eight hundred and fifty-five.
Witness,
MAC LEOD,
3, Hanley Crescent,
Camden Town.
H. CHAUDET.
(L.S.)