Carbon for Electrical or other Purposes.
Year: 1886

page_text: Carbon for Electrical or other Purposes.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co. Patent Agents,
Southampton Buildings in the County of Middlesex, do hereby declare the nature
of this invention and in what manner the same is to be performed, to be par-
ticularly described and ascertained in and by the following statement:-
My invention relates to the preparation of carbon for use in its different appli-
cations in the arts.
Carbon being highly refractory and infusible in its nature, and at the same time
an excellent conductor of electricity, is extensively employed for various purposes,
and more especially in the construction of electrical apparatus. It is consumed in
large quantities in the manufacture of electrodes or pencils for electric arc-lights,
and in the formation of negative plates for voltaic batteries. It is also largely
used for contact points and surfaces in microphones and telephonic transmitters,
and for other like purposes.
The principal source from which the carbon of commerce is obtained, is the
retorts of gas works, in which it accumulates in great quantities as a bye product.
It is deposited in these retorts in exceedingly hard masses, which can only be
broken away and removed with much difficulty. Formerly the carbon pencils and
plates required for electrical purposes, were sawn or cut bodily from these masses.
This was necessarily a laborious, difficult and expensive operation, owing to the
extreme hardness and tenacity of the material.
The present improved process of manufacture, consists in breaking up and
pulverizing the crude masses of carbon procured from the gas retorts, by grinding
them in a suitable mill to a very fine powder. This powder is agglomerated by
means of syrup or other like material, forming a stiff paste which may be pressed
into moulds or formed in dies in any required form. The moulded articles are
subsequently baked by subjecting them to a very high temperature for a consider-
able length of time thus forming them into solid masses.

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The nature of the raw material as it comes from the retorts is such that the
operation of grinding is a tedious and expensive one, and hence a substitute has
been sought, by carbonizing different kinds of wood and vogetable substances of a
ligneous nature, thereby producing a form of carbon commonly known as charcoal,
which is soft and easily pulverized. Experience, however, has shown that carbon
obtained in this manner does not fulfill the necessary requirements, especially for
electrical purposes, as the material contains siliceous and other earthy impurities
which render it unsuitable for such uses.
I have discovered that by carbonizing any of the various species of marine algae,
commonly called sea-weed, a carbon product is obtained in the form of soft masses,
which are capable of being readily ground or pulverized, and are free from all
mineral impurities. Carbon derived from this source is found by experiment to be
more suitable, especially for electrical uses, that any carbon yet known, while at
the same time, it is inexpensive to produce by reason of the vast abundance and
trifling cost of the raw material, and the simplicity of the treatment required to fit
it for use:
In carrying out my invention the algae or sea-weed which has been collected is
placed in convenient quantities in a suitable vessel, and thoroughly washed and
cleansed by subjecting it to the action of hot water or steam.
It may be found advantageous to use a dilute acid bath to cleanse the sea-weed
from the silica or sand and the minute shells that adhere to it. The material is
dried and is then carbonized, by being placed in closed retorts and subjected to a
high temperature for a considerable time in a well known manner.
The resulting
product is then treated with dilute muriatic or other suitable acid, and dried. It
is then a perfectly pure form of carbon, in soft masses or lumps which may be
easily crushed between the fingers and constitutes my improved product which
may afterwards be ground or pulverized by means of any suitable machinery, and
manufactured into various articles by the usual processes.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is:—
Blocks, plates or rods, adapted for electrical or other uses, and consisting of
compressed carbonized algae or sea-weed.
Dated 4th oth
1000