IMPROVED METHODS FOR PURIFYING Gutta Percha
Year: 1873

page_text: LETTERS PATENT to Thomas Cattell, of Clarendon House, No. 25,
Clarendon Square, in the County of Middlesex, M.D., for the
Invention of "IMPROVED METHODS FOR PURIFYING Gutta Percha.”
Scaled the 15th August 1873, and dated the 17th February 1873.
PROVISIONAL SPECIFICATION left by the said Thomas Cattell at the
Office of the Commissioners of Patents, with his Petition, on the
17th February 1873.
I, THOMAS CATTELL, of Clarendon House, No. 25, Clarendon Square,
5 in the County of Middlesex, M.D., do hereby declare the nature of
the said Invention for "IMPROVED METHODS FOR PURIFYING GUTTA PERCHA,"
to be as follows:-
-

page_text: and dated the 17th day of February 1859, No. 446, so far as to dissolve
or bring the same into the state or condition of a solution of gutta
percha.
Having obtained the gutta percha solution by the means aforesaid, in
order to deprive the gutta percha solution of impurities intermixed
therewith the solution is to be filtered or strained, which may be effected
by pressure produced either by hydrostatic or other suitable mechanical
The filtered or strained gutta percha solution is then subjected
to the processes Nod. 1,2, and 3, according to the degree of purity which
may be desired.
means.
1. By passing through or into the filtered or strained gutta percha
solution by any convenient means the vapour of alcohol, or methylated
alcohol, pyroxylic spirit, or amylic alcohol. This step in the process
will be materially accelerated by passing dry or superheated steam with
the alcohol into the vessel or apparatus containing the filtered solution.
This operation to be repeated or continued until the purified gutta percha
is deposited or separated from the solution.
2. Any of the before-mentioned alcohols may be added in a heated
state in quantity sufficient to effect the deposition or separation of the
gutta percha from the solution. When, however, either of the alcohols
is added in its cold state, heat is applied until the deposition or separation
aforesaid is effected.
3. The gutta percha solution is to be forced or allowed to pass into a
chamber, vessol, or other suitable apparatus in a sprey-like or divided
form, and currents of steam simultaneously blown into the chamber or
vessel so as to meet or come in contact with the spreyed solution. The
steam will be made to pass out of the chamber or vessel, and it will
carry with it the fluid solvent of the gutta percha, and the purified
gutta percha will be deposited in the chamber, a condenser or cooler
being employed to collect the solvent employed in the manufacture of
the gutta percha solution.
The gutta percha in a shaven, shredded, or divided condition is placed
in a suitable vessel containing water in sufficient quantity to allow the
gutta percha to be kneaded along with benzole, petroleum spirit, or other 35
solvent of gutta percha. The contents of the vessel are to be heated by

page_text: any convenient means until the gutta percha is softened, so as to render
its being easily mechanically strained. And this operation may be
repeated until the gutta percha is sufficiently freed from impurities.
Should any portion of the solvent employed be present with the gutta
percha it may be removed by submitting tho gutta percha to a current
of steam applied by any convenient means.
In my before-mentioned Specification I have described a process which
is therein termed "the process of congelation." Instead of adopting
any of the three steps described under that process to get rid of the
solvent; I break up the solid or congealed mass into small particles, and
drop or pass the same into a chamber, cylinder, column, or other suitable
apparatus, and pass currents of steam into the chamber or other apparatus
employed. The steam holding the vapor of the solvent used may be
condensed by passing it into a suitable condenser or cooler, and the
purified gutta percha will be left in the chamber or other apparatus
employed. The same result will be obtained by passing the vapour of
alcohol, methylated alcohol, or other alcohol into the chamber or
apparatus. The vapours of the alcohols, and the vapours of the solvent
of the gutta percha solution, may be allowed to pass into a condenser
or cooler and collected.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Cattell in the Great Seal Patent Office
on the 16th August 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
CATTELL, of Clarendon House, No. 25, Clarendon Square, in the County
of Middlesex, M.D., send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by. Her Letters
Patent, bearing date the Seventeenth day of February, in the year of
our Lord One thousand eight hundred and seventy-three, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Thomas Cattell, Her special licence that I,
the said Thomas Cattell, my executors, administrators, and assigns, or
such others as I, the said Thomas Cattell, my 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 vond, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVED METHODS FOR PURIFYING
GUTTA PERCHA," upon the condition (amongst others) that I, the
said Thomas Cattell, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and
scals, 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 Thomas Cattell, do hereby declare
the nature of said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by
following statement :-
My Invention of improved methods consists in treating gutta percha
in its amide on insure state by the following NAS

page_text: dated the 17th day of February 1859, No. 446, so far as to dissolve
or bring the samo into the state or condition of a solution of gutta
percha.
Having obtained the gutta percha solution, in order to free such
solution from its impurities the solution is to be filtered or strained,
which may be effected by pressure produced either by hydrostatic or
other suitable mechanical or filtering means. The filtered or strained
gutta porcha solution is then subjected to any one of the following
operations or processes A., B., C. :—
A. The filtered or strained gutta percha solution being contained in
a suitable vessel or apparatus, the vapor of alcohol cither in its
methylated or pure state, pyroxylic spirit, or amylic alcohol is passed
through or into it by any suitable means. This step in the process will
be materially necelerated if dry or superheated steam with the alcohol
bo passed by suitable means into the vessel or apparatus containing the
filtered gutta percha solution. This operation is to be continued until
the purified gutta percha is deposited or separated from the gutta percha
solution.
The temperature of the gutta percha solution when manufactured
with benzole or other hydrocarbon solvents of gutta perchia should be
sufficiently high to prevent any solidification thereof during the process.
But when the gutta percha solution is obtained with bi-sulphide of
carbon or other solvents of gutta percha, operating on the gutta percha
at the ordinary temperaturo of the atmosphero, artificial heat will not bo
required. Agitation of the solution during the process is desirable.
B. The vapor of alcohol, either in its methylated or pure stato,
pyroxylic spirit, or amylic alcohol, is to be added to the gutta percha
solution in a heated condition, in quantity sufficient to effect the
deposition or separation of the gutta percha from the gutta percha
solution. When, however, any one of the alcohols is added at its
ordinary temperature, heat is to be applied until the deposition or
separation of the gutta porcha is effected.
C. The gutta porcha solution is to be forced or allowed to pass into a
chamber, vessel, or other suitable apparatus in a sprey-liko or divided
form, and currents of steam are to be simultaneously blown or directed
into the chamber or vessel, so as to meet or come into contact with the
spreyed gutta percha solution. The steam, with the vaporized solvent of

page_text: given under process A. with reference to the temperature of the gutta
percha solution are to be observed in the carrying out of this process.
PROCESS No. 2.
The gutta percha in a shaved or shredded condition is placed in a
suitable vessel containing water in sufficient quantity to allow the gutta
percha to be kneaded along with benzole, petroleum spirit, or other
solvent of gutta percha. The contents of the vessel are to be gradually :
heated by any convenient means until the gutta percha is softened, so
that it may be easily strained mechanically, and this operation may bo
repeated until the gutta percha is sufficiently freed from impurities.
Should any portion of the solvent employed be present with the gutta
percha, it may be removed by submitting the gutta percha to a current
of steam applied by any convenient means. A condenser may be om-
ployed to collect the vaporized solvent so driven off.
PROCESS No. 3.
The gutta percha in a shaved or shredded condition is placed in a
suitable vessel or apparatus, and submitted to a mixture of benzole or i
other rectified products of coal tar, naptha, and methylated or other
alcohols, or petroleum spirit, and methylated or other alcohols, or
bi-sulphide of carbon, and methylated or other alcohols, in equal or
nearly equal proportions. The contents of the vessel or apparatus are to
be gradually heated, and while this is taking place the gutta percha is a
to be kneaded by any convenient mechanical means until it becomes so
softened as to be capable of being readily forced through strainers,
perforated diaphragms, or other similar means, whereby the gutta
percha will be freed from its impurities. It is then to be transferred to
a chamber or other suitable apparatus, and submitted to the action of a
steam, applied by any suitable method. A condenser may be employed
to collect the mixed fluid evolved or driven off.

page_text: solvents of gutta percha to 32° Fahrenheit, as therein-mentioned, or of
adopting any of the three steps described in my said Specification to get
rid of the solvent, I simply withdraw the heat required for the manu-
facture of the gutta percha solution, and when it becomes solid, which it
will at the ordinary atmospheric temperature, I break it up into small
particles, and drop or pass the same into a chamber, cylinder, column, or
other suitable apparatus, and convey currents of steam by mechanical
means into the chamber or other apparatus. The steam and vapor of
the solvent used may be condensed by passing them into a suitable
condenser, and the purified gutta percha will be left in the chamber or
apparatus employed. The same result will be obtained by passing the
vapor of methylated or other alcohols into the chamber or apparatus.
The vapors of the alcohols and the vapors of the solvent of the gutta
percha may be passed into a condenser and collected..
Having now particularly described and ascertained the nature of my
said Invention, and in what manner the same is to be performed, I wish
it to be understood that I do not claim as part of my Invention the
treatment of crude gutta percha for the purpose of obtaining the gutta
percha solution, mentioned or referred to under process No. 1, herein-
before described, nor do I claim as part of my Invention "the process of
congelation," mentioned or referred to under process No. 4, herein-before-
described, but I claim as my Invention the processes lettered A., B., C.,
under process No. 1, and the several processes numbered 2, 3, and 4,
herein-before described, except the said disclaimed parts.
In witness whereof, I, the said Thomas Cattell, have hereunto
set
my hand and seal, this Sixteenth day of August, in the year
of our Lord One thousand eight hundred and seventy-three.