Improvements in the Manufacture of Artificial Cork.
Year: 1894

page_text: Date of Application, 18th July, 1894-Accepted, 23rd Mar., 1895
1
i
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Artificial Cork.
I GUSTAV HAGEMANN of 13 Moltkestrasse, Ludwigshafen on the Rhine,
Germany Engineer 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 :-
This invention relates to certain improvements in the manufacture of artificial
cork from cork chips or fragments, and the object of the invention is to provide a
certain improved mode of procedure whereby the cork chips or fragments which
are waste products may be utilized for the formation of bottle stoppers and other
articles which are usually made of cork. My invention also relates to certaia
improvements whereby the artificial cork is produced in a state suitable for being
moulded to form; and whereby the product is rendered more or less flexible, all as
hereinafter fully set forth.
The cork is cut small by any known means and is reduced to different sizes by
means of sieves. The cork powders thus obtained are now separately freed from
impurities and the heavier components by means of a current of air.
The collodion serving as cement is obtained by dissolving nitrated, cellulose in
acetone. Other known solvents may be used but the application of acetone has
proved to be of special advantage.
The solutions can be employed at different grades of concentration; a solution
holding 8% of nitrated cellulose will be sufficient in most cases.
The cork powder is intimately mixed with the collodion either by hand or by
means of machines and, the mass is then passed into moulds of any convenient
form..
It is preferable to make the moulds of perforated sheet metal so that the ensuing
dessication finds no obstruction for the evaporation of the acetone.
The filled and closed moulds are now placed in hermetically closed chambers
which can be heated indirectly by steam, hot water and the like. When the
chambers are closed and heated the temperature is only raised sufficiently for the
evaporation of the liquid employed the nitrocellulose a pipe leads from the chamber
through a cooling room wherein the vapors of the solvents are condensed.
As soon
as the products of condensation cease to flow off, the dessication is finished and the
manufactured objects can be taken from the moulds.
The products of condensation are stored up in suitable receptacles in order to be
employed again for dissolving the nitro-cellulose. The dessication can also be
effected in the open air in drying chambers or in evacuation spaces; in the two
first cases the time of dessication will be very long and the solvent is lost, but in
employing evacuated spaces the regeneration of the solvent becomes difficult.
According to the desired solidity and elasticity of the artificial cork to be obtained,
different quantities of collodion will be employed, for coarse cork powder it is
sufficient to employ equal parts of the cork powder and of an 8% solution of nitro-
cellulose while for fine cork powder it is advisable to use greater quantities of
binding material.
By exerting more or less pressure in the moulds, the artificial cork can be
obtained in different degrees of density.
By an addition of a fat oil the flexibility of the cork is highly increased also
rosins can be added to the solutions.

page_text: The product obtained in the above described manner has almost the same
properties as the natural cork and surpass the same in homogenity, offering besides
the advantage that the artificial cork can be made in any desired dimensions.
The cement or binding material employed is especially appropriate to the
manufactory of artificial cork, as it is colourless and free of odour, completely
harmless, very resisting and in no way exposed to decomposition, also the
imflamability of the artificial cork is not greater than that of the natural cork, and
can be much decreased by making suitable additions, such as sulphate of ammonium
soluble glass or other matter used for impregnating materials in order to make them
fire proof.
"
For certain purposes an addition of foreign matters to the artificial cork may be
desirable, for instance for jacketting steam pipes or for using the artificial cork as
building material-au addition of kieselguhr may be recommended, in other cases au
addition of the fibrous material may be of service.
" J
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The improvements in the manufacture of artificial cork consisting of cork
powders and collodion and binding material substantially as described.
2. The process of manufacturing artificial cork by pressing cork powder mixed
with collodion in closed moulds and heating the mass in this compressed state in
hermetic chambers till the solvent of the collodion is evaporated and which may be
regained by condensation substantially as described.
3. The improvements in the manufacture of artificial cork with additions of
kieselguhr or fibrous material for insulation and for building materials substantially
as described.
Dated this 18th day of July 1894.
HUGHES, ELI & HUGHES,
76, Chancery Lane, W.C., Agents for Applicant.