Improvements in Pyroxylin Compounds, and in the Processes for Manufacturing the same.
Year: 1894

page_text: Date of Application, 6th Nov., 1894-Accepted, 15th Dec., 1894
Improvements in Pyroxylin Compounds, and in the Processes for
Manufacturing the same.
I, ROBERT CHARLES SCHÜPPHAUS, Chemist, of No. 118 Pennsylvania
Avenue, Brooklyn, County of Kings, and State of New York, U.S.A., 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:
My invention relates to pyroxylin compounds, both solid and liquid, and to
processes for manufacturing the same. Its object is to replace the pyroxylin-
camphor compositions, which, serviceable and useful as they are, yet possess well
known disadvantages.
It has been asserted that melted camphor is a solvent of the variety of pyroxylin
employed in the manufacture of these compositions, and processes founded on this
supposed property have heretofore been described in the Specifications of Letters
Patent and in various scientific papers.
It is well known that the melting point of camphor is higher than the temperature
at which pyroxylin is decomposed, and my own extended investigations in this
direction have convinced me that such processes are not, as yet, perfectly under-
stood. When finely comminuted camphor and pyroxylin, containing a slight
percentage of water, are heated together under great pressure, a material of horny
appearance results. But, though it is unnecessary to raise the temperature to the
melting point of camphor, there are always signs of decomposition of the pyroxylin.
Dioxyd of nitrogen, when conducted over camphor, liquefies it, and this liquid
forms an excellent solvent of pyroxylin. This reaction may have some part in the
conversion. That the use of camphor alone as a solvent of pyroxylin is not
practical, would seem evident from the fact that all manufacturers have had recourse
to the employment of more or less expensive solvents, such for example, as wood
and grain alcohol, fusel oil and its various distillates, acetone and the like, im
conjunction with camphor. From the action of camphor on pyroxylin there results
a new substance, which, although some of the camphor may be in an unstable
combination, is endowed with new properties, its most important characteristic
being that it is plastic at a temperature of about 75° C.
I have found that there exists a whole class of well defined substances which
may replace camphor in this process and those of sufficiently low melting point are
solvents of pyroxylin, per se, when they are in the molten state. This class is
formed by the alkoyl derivatives of the aromatic amins and their products of
substitution.
1
TI
11
Formanilid,
Ortho-acetphenitidin,
Ortho-acetotoluid,
Para-acetphenitidin,
Para-acetotoluid,
Benzanilid,
melting point 46º C.
دو
70°
"
"
"
107°
"
"
"
133°
"
"
"
147°
"
"
161°
"
"
وو
and likewise the bromo- and nitro-derivatives of such compounds.

page_text: both as regards point of fusion and ready solubility in other solvents, should the
employment of the latter seem desirable.
In practice I prefer to use the acetotoluids. When toluene, now cheaper than
benzene, is nitrated, a mixture of chiefly ortho- and para-nitrotoluene, with only
very little of the meta-derivative, is formed. The operator has it in his power to
make either the ortho- or the para-compound preponderate. This crude nitro-
toluene furnishes, on reduction, a mixture of the corresponding toluidins, from.
which by proper methods the acetotoluids are obtained. These are specially
adapted to my process. The ortho-compound melts at 107° C., the para-, in the
pure state, at 147° C. Yet a mixture of equal weights of ortho- and para- is
practically liquid at the heat of the water-bath.
The mode of procedure employed in making my new compounds is similar to
that usually employed in the manufacture of the pyroxylin-camphor compounds,
such as pyralin, xylonite and celluloid. The materials are mixed, rolled, pressed,
sheeted or stuffed just as these compounds are, with the difference only, that the
addition of a liquid solvent, such as alcohol for instance, may be omitted. All
these operations are so thoroughly understood by those skilled in this art that it is
unnecessary here to further describe them. The resulting material is inodorous,
free from the troublesome warping of the camphor compositions and does not
develop efflorescences on its surface, as some other pyroxylin compositions do.
If a varnish or other liquid compound is desired, it is only necessary to add.
to the mixture of pyroxylin and acetotoluid a sufficient quantity of solvent such
as wood alcohol or acetone or a mixture of both, to which butyl or amyl acetate
may be added.
It is hardly necessary to mention that these new solvents may be used in
conjunction with camphor.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The process herein described, which consists in mingling pyroxylin with one
or more alkoyl derivatives of aromatic amins or their products of substitution in
a state of fusion or of solution, substantially as described.
2. The process herein described, which consists in treating pyroxylin with one or
more alkoyl derivatives of aromatic amins or their products of substitution under
heat and pressure, substantially as described.
3. As a new article of manufacture the product herein described, cousisting of a
compound of pyroxylin with one or more alkoyl derivatives of aromatic amins or
their products of substitution, substantially as described.
Dated this 6th der of Nawambon 1001
R. C. SCHÜPPHAUS,
Per W. H. Beck,
115, Cannon Street, London, Agent.