An Improved Insulating Material for Electrical Purposes, and Method of Preparing same.
Year: 1893

page_text: Date of Application, 15th Feb., 1893
Complete Specification Left, 1st Mar., 1893-Accepted, 1st Apr., 1893
PROVISIONAL SPECIFICATION.
An Improved Insulating Material for Electrical Purposes, and
Method of Preparing same.
We, ADOLF GENTZSCH, Mineralogist, 1 Kurhausgasse 2, JULIUS GOLDSCHMIDT,
Consul General for the United States of America in Vienna, Austria IX Wasa-
gasse 2 and ETIENNE RITTER VON SCANAVI, Banker 1 Elisabethstrasse 15, all
of Vienna, aforesaid, do hereby declare the nature of this invention to be as
follows:-
-
This invention relates to an improved insulating material for electrical purposes
and to a method of preparing same.
The fundamental insulating body of the material in question consists of shellac,
another kind of resin or resins which is mixed with the shellac in the manner here-
after described, and certain addition which are calculated to give the insulating
substance as much as possible the properties of gutta percha. These consist for
example of a hydro carbon such as one having the formula C₁H₁, for instance
anthracine and various oils as birch tar oil and aniline oil.
14' 10
As a result of about 1700 experiments the following materials and proportions
have been found particularly advantageous:
3.8
"
"
"
15.4
وو
"
ور
aniline oil
CH10
An insulating substance compounded nearly according to these proportions fulfils
all demands which can be made upon such a substance, such as: high insulating
resistance, and freedom from acids (free acids). It is also non hygroscopic,
satisfactory in its flexibility and elasticity, proof against changes of temperature,
has a low melting point, together with a relatively high solidifying point and is
practically impermeable to water.
For the preparation of this substance, the following method may be employed:
The shellac and the other resins are each component separately placed in the
desired quantity in proper receptacles and water is poured over them, in order to
bring into solution all materials or admixtures which occur in these bodies and are
soluble in water. The more carefully this is done so much better is the effect and
it is therefore advisable to repeat this operation as often as possible, and to knead
the bodies in the water frequently.
The same thing is done with the oils used for the purpose, with this difference
only, that these latter are boiled with water until all soluble components have passed
into solution. The shellac and the resins freed in this manner from all extractible
substances, are, after previously being drained of water, placed in equal proportions
in a suitable vessel which should be adapted to contain a quantity five to ten times
that which is to be treated, and these are melted together in this at a temperature
of about 150 to 180 degrees C. After one half to three quarters of an hour
approximately the mass which is originally clear, swells, becomes bulky and spongy
and decomposes. The vessel is now closed with a well-fitting-cover and the
temperature gradually raised to 400 degrees C. or even above that. The previously
decomposed substance now melts afresh and changes its yellow colour into a dark
red brown and from this to a brown black, when the complete combination of the
melted substances will be found to be attained.
This new product which is entirely impervious to water, is in its cold state of a
brittle nature but is now capable of combining with oils, fats or waxes, without

page_text: being subject to further decomposition. The hydrocarbon C₁H₁, is now melted
separately and the oils which are to be added (birch-tar-oil and aniline oil) are
heated to remove any contained water in the latter.
This is best done in an oil-bath at a temperature up to 160 degrees C. till all the
water has escaped in the shape of steam or vapour.
After these preparations the determined quantities of the several substances, are
placed in a vessel and are melted together.
The object of the additions of oil is to thin the substance according to the
quantity of the same added.
The birch-tar-oil and aniline oil are selected on account of the peculiarity, which
these oils possess of a particular impermeability to water which impermeability is
imparted to the insulating material.
The hydro carbon C₁₁ is added for the purpose of rendering the brittle
resinous substance obtained in the foregoing manner soft and plastic for which
purpose it is particularly adapted in consequence of its insolubility in water.
If the substance is to be made firmer or harder, less oil is added and vice versa.
Dated this 15th day of February 1893.
PHILIP M. JUSTICE,
Chartered Patent Agent for the Applicants.
COMPLETE SPECIFICATION.
An Improved Insulating Material for Electrical Purposes, and
Method of Preparing same.
We, ADOLF GENTZSCH, Mineralogist, 1 Kurhausgasse 2, JULIUS GOLDSCHMIDT,
Consul General for the United States of America, in Vienna, Austria, IX Wasa-
gasse 2, and ETIENNE RITTER VON SCANAVI, Banker, 1 Elisabethstrasse 15, all
of Vienna, aforesaid, 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 an improved insulating material for electrical purposes
and to a method of preparing same.
The fundamental insulating body of the material in question consists of shellac,
another kind of resin or resins which is mixed with the shellac in the manner here-
after described, and certain additions which are calculated to give the insulating
substance as much as possible the properties of gutta percha. These consist for
example of a hydro carbon such as one having the formula C₁4H10 for instance
anthracine and various oils as birch tar oil and aniline oil.
As a result of about 1700 experiments the following materials and proportions
have been found particularly advantageous:
About 38.5 parts of shellac
وو
colophony (rosin)
38.5
"
""
3.8
birch tar oil
دو
"
""
3.8
aniline oil
"3
"
"
15.4
"
دو
"
C14H10
An insulating substance compounded nearly according these proportions fulfils
all demands which can be made upon such a substance, such as high insulating
resistance, and freedom from acids (free acids).
It is also non-hygroscopic, satisfactory in its flexibility and elasticity, proof
against changes of temperature, has a low melting point together with a relatively
bigh solidifying point, and is practically impermeable to water.
For the preparation of this substance the following method may be employed:
The shellac and the other resins are each component separately placed in
the desired quantity in proper receptacles, and water is poured over them in order
to bring into solution all materials or admixtures which occur in these bodies and

page_text: are soluble in water. The more carefully this is done so much better is the effect,
and it is therefore advisable to repeat this operation as often as possible, and to
knead the bodies in the water frequently.
The same thing is done with the oils used for the purpose, with this difference
only, that these latter are boiled with water until all soluble components have
passed into solution. The shellac and the resins freed in this manner from all
extractible substances, are, after previously being drained of water, placed in
equal proportions in a suitable vessel which should be adapted to contain a quantity
five to ten times that which is to be treated, and these are melted together in this
at a temperature of about 150 to 180 degrees C. After one half to three quarters
of an hour approximately the mass which is originally clear, swells, becomes bulky
and spongy, and decomposes. The vessel is now closed with a well fitting cover and
the lemperature gradually raised to 400 degrees C., or even above that. The
previously decomposed substance now melts afresh and changes its yellow colour
into a dark red brown and from this to a brown black, when the complete com-
bination of the melted substances will be found to be attained.
This new product which is entirely impervious to water, is in its cold state of a
brittle nature but is now capable of combining with oils, fats or waxes, without
being subject to further decomposition. The hydrocarbon C₁₁o is now melted
separately, and the oils which are to be added (birch tar oil and aniline oil) are
heated to remove any contained water in the latter. This is best done in an oil-
bath at a temperature up to 160 degrees C, till all the water has escaped in the
shape of steam or vapour. After these preparations the determined quantities of
the several substances are placed in a vessel and are melted together. The object of
the additions of oil is to thin the substance according to the quantity of the same
added. The birch tar oil and aniline oil are selected on account of the peculiarity
which these oils possess of a particular impermeability to water, which imper-
meability is imparted to the insulating material.
The hydrocarbon C₁H₁ is added for the purpose of rendering the brittle
resinous substance obtained in the foregoing manner soft and plastic, for which
purpose it is particularly adapted in consequence of its insolubility in water.
If the substance is to be made firmer or harder, less oil is added, and
vice versa.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
1. The improved insulating material consisting of shellac and another suitable
resinous substance, or substances, mixed with suitable oils and anthracene (C₁H₁),
substantially as described.
2. The improved insulating material consisting of shellac and colophony (rosin)
mixed with birch tar oil, aniline oil and anthracene (C₁H₁0) substantially as
described.
14
3. The method of preparing the insulating material described which consists in
treating certain of the bodies with water either cold or boiling for the purpose of
dissolving the substances which are soluble in water and then combining the
insoluble substances, substantially as and for the purpose set forth.
4. In the preparation of the insulating material described, melting the resins until
decomposition begins, and then continuing the melting until a complete combination
of the melted substances takes place, substantially as described.
5. The improved insulating material and method of preparing same, substantially
as herein described.
Dated the 2nd 1
SML 1002