Year: 1899

page_text: Date of Application, 1st Mar.. 1899 -Accepted, 22nd Apr., 1899
I, CHRISTIAN WILHELM LUTHER, of the Firm Actien-Gesellschaft für mechanische
Holzbearbeitung A. M. Luther, of Reval, Russia, Director, 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:-
--
It has often been tried to replace shellac, that is now exclusively used in the
manufacture of spirit wood polish, by cheaper resins, for instance, copal however
without success.
We find published by L. E. Andés for instance in his book, Die technischen
Voll-endungsarbeiten der Holzindustrie, Wien 1881 pag. 146 the following pre-
scription for a copal polish: I pulverise 2 parts of a good light Manilla copal
very fine, I pour on it in a glass bottle 12 parts of alcohol of 96 degrees and
dissolve the alcohol by shaking the bottle. However he adds himself on page 146
of his book, that practically no good results have been gained by using this
polish, as it is impossible to polish wood with this polish in the same way as this
is done with Shellac Polish.
After many trials I have also come to the result, that the Copal Polish made
after the prescription of Andés is practically worthless. When rubbing this
polish on the wood that is to be polished there soon forms, as soon as the pores
of the wood begin to fill up, a grevish sticky skin on the surface of the wood
that prevents the polishing hall sliding and the polish getting shiny. When
polishing with ordinary French Shellac Polish, the surface that is being polished
in a certain state of the polishing process looks dull, however this dull look is
caused only by the linseed oil that is used in polishing and which is spread
thinly over the whole surface of the article in polishing.
This thin coating of linseed oil makes the polishing ball glide easily on the
shiny and not sticky surface of resin that is underneath it. When the polishing
is done this very finely spread coating of oil is removed by a soft piece of fabric
and a few drops of spirit, after which operation the full shine of the polish appears.
Contrary to this, one gets with the polish as mentioned first (Copal Polish) only
a smeary dull surface.
The following process however does away with this fault and produces a Copal
Resin Polish that may be used exactly in the same way as the Shellac French
Polish and is even superior to it, so far that it gets harder, lighter, and is cheaper.
This new way of producing this polish is founded on this perception that the
Copal gets its sticking qualities from the essential oils enclosed in it which com-
bine during polishing with the linseed oil to the smeary mass as mentioned above,
which prevents the gliding of the polishing ball.
To make the Copal Resin fit to be used for polishing purposes these essential
oils must be got away and this, after long trials, I have succeeded in doing by
making it turn into resin. I do this as follows:-
1. The Copal Resin is pulverised very fine and then exposed for a long time to
the influence of the air, however this way of doing it would require from 1 to 3
years time according to the quality of the Copal Resin used.

page_text: 2. The Copal Resin is ground quite fine about as fine as flour. During the
grinding, water is added as otherwise the sticky resin would be pasting up the
grinding apparatus.
The resulting creamy like mixture composed of resin and water is then dried,
and by the aid of disintegrators and sieves made into a fine greyish looking powder,
which in a thin layer is during 2 or 3 weeks exposed to a temperature of from 45
to 60 degrees Celsius. As not all Copal Resins contain the same quantity of
essential oils, it is necessary to find out the best temperature by a trial. If the
temperature is too low, the time required for turning the essential oils into resin
is too long, if the temperature is too high, the Copal Resin melts and forms a
kind of cake which would have to be ground again.
In both cases No. 1 or No. 2 the turning of the essential oils into resin makes
itself known through the disappearance of the spicey smell of fresh copal and
by the appearance of another also very characteristic smell, at the same time
the greyish white colour of the powder changes into a vellowish colour.
The Copal Resin, after having been thus prepared, is then dissolved in spirits
in any well known way, then filtered, and I get a polish that is used exactly in
the same way as ordinary Shellac French Polish.
The spirits used for dissolving the copal may however be partly replaced by
ether. A polish that is prepared in this way does not sweat out any oil, as the
French Polish does, and allows of a much quicker polishing because the ether
evaporates much quicker, it must however be treated in polishing a little different
from the ordinary French Polish. Take a little less polish on the polishing ball
than you would take of ordinary French Polish, and rub a small space only, over
which you can rub oftener than with ordinary polish, ether polish drying so
much quicker. Use very little pumice stone and little oil, and only then when
the pores of the wood are filled with polish so that the surface glistens already.
The polishing ball must not be lifted while polishing, as long as there is some
polish still in it, otherwise the polish contained therein gets thick and the polish
cannot ooze out.
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 manufacture of Copal Resin Wood Polish in the following manner:--
1. Grinding the Copal Resin to a very fine powder and then exposing same
in a thin layer to the air during 1 to 3 years for the purpose of turning essential
oils contained therein into resin, then the manufacture of polish by the aid of
spirits, in some cases adding ether as described.
2. Grinding the Copal Resin to a fine powder like flour, then exposing same in
a thin layer from 2 to 3 weeks, to a temperature of between 45 and 60 degrees
Celsius for the purpose of turning the essential oils into resin, then manufacturing
of polish by the aid of spirits in some cases adding ether, as set forth.
Daten THIS ISL CHY OT Larch EX
aten tHIS ISL (HY OF ALarch
X3
H. GARDNER.
Patent Agent, 166 Fleet Street, London,
Agent for the said Christian Wilhelm Luther.