Improved Insulating Material for Cables, and Process of Making same
Year: 1895

page_text: Date of Application, 6th May, 1895-Accepted, 21st Dec,
1895
COMPLETE SPECIFICATION
Improved Insulating Material for Cables, and Process of
Making same
We, ADOLF GENTZSCH, of No 1, Stiftgasse, Mineralogist, and ETIENNE
RITTER VON SCANAVI and NIKOLAUS RITTER VON SCANAVI sole Partners in the
Firm trading under the style or name of J N Scanavi, of No 5 Braunerstrasse,
Bankers, all of the City of Vienna, Empire of Austria, do hereby declare the
nature of our said 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 insulating material for electric cables, wires and the
like, such material being made of those minerals, which belong to the hornblende
species (amphibole, amianthus, augite) and especially those of a fibious nature
The material may either be used alone, or it may be impregnated or mixed with
a known insulating substance The minerals may also be u ed in their natural
state, or after having been worked up in the form of fibres, twine, cords, fabric,
plates or strips In order that the material possesses a high insulating property,
the minerals are subjected to the following treatment
The fibious minerals above-mentioned are put into a boiler, either in their
natural state or wrapped on the cable or wire to be insulated, and mixed with a
suitable known insulating substance or it is more preferable to put same into a still
and heat until they commence to pass over
This treatment requiring a considerable time, the water of crystallization is duiven
out of the fibrous minerals, which latter thus become so impregnated with the added
insulating substance that they are rendered impervious to moisture
The propor-
tions of the materials employed may vary but a good result will be obtained with
a mixture of about 10% of amianthus or other of the hornblendes and 90% of
the insulating substance such as rubber
The resulting composition may be used in its present state, but it has been found
preferable to first ladle same out of the boiler by means of suitable vessels having
Sieve-like bottoms, the remaining mass being strained off by heating the composition
to a temperature above the boiling point of the insulating material employed The
composition thus obtained may now be used as an insulating material either in that
state or mixed with a more flexible material the insulating material being either
pressed round the cable or wire to be insulated, or attached to same in any other
suitable well known manner
The fibrous material abovementioned may also be put into a strong vessel,
heated to red-heat and then allowed to cool to about 200° to 250° Centigrade,
when it is added to an insulating substance already brought to a temperature
which will not injure the properties of the mixture, on addition of the heated
minerals Care must be taken, however that the temperature of the mineral. 18
not allowed to fall so low that they may again absorb the moisture peculiar to them,
from the air
When it is not required that the cable possesses a high insulating resistance, the
mater als 100vementioned may be made in the form of twine, cord, fabric, plates or
strips and wrapped or spun round the cable or wire to be insulated, which coveiing may
also be coited with insulating material for preventing the wires or cables making
contact with each other
It will be evident that the cables may be wrapped with lead in the usual manner
01, instead of lead or in comoination with such lead wrappers the cable may be

page_text: provided with wire spun round same in a well known manner to prevent the cables
being injured by outside influences, but without materially destroying the flexibility
of same
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
1 An insulating material for cables, wires and the like, composed of amphibole,
amianthus, augite or other mineral of the hornblende species, such material being
either used alone or impregnated or mixed with a known insulating substance,
substantially as described
2 Process of making the insulating material as described in Claim 1 consisting
of heating amphibole, amianthus, augite or other mineral of the hornblende
species either alone or wrapped round the cable to be insulated together with a known
insulating substance, the water of crystallisation being thereby driven out of such
minerals which thus become impregnated with the added insulating substance,
substantially as described
3 A modification of the process of making insulating material as set forth
in Claim 1, consisting in heating the fibrous minerals and then mixing same with
a separately-heated and known insulating substance, substantially as described
4 The method of wapping cables insulated as described in the foregoing
claims with awe in a well known manner substantially as described
Dated the 6th day of May 1895
PHILIP M JUSTICE,
Filing Agent