IMPROVEMENTS IN THE MANUFACTURE OF MATERIAL TO FORM ARTIFICIAL IVORY, AND APPLICABLE ALSO AS A SUBSTITUTE FOR HORN, CORAL, MALACHITE, VULCANITE, INDIA RUBBER, GUTTA PERCHA, AND FOR: VARIOUS OTHER PURPOSES
Year: 1881

page_text: LETTERS PATENT to Frederick William Cottrell, of 35, Calthorpe Street, W. C.
in the City of London and County of Middlesex, for an Invention of
IMPROVEMENTS IN THE MANUFACTURE OF MATERIAL TO FORM ARTIFICIAL
IVORY, AND APPLICABLE ALSO AS A SUBSTITUTE FOR HORN, CORAL,
MALACHITE, VULCANITE, INDIA RUBBER, GUTTA PERCHA, AND FOR: VARIOUS
OTHER PURPOSES."
PROVISIONAL SPECIFICATION left by the said Frederick William Cottrell
at the Office of the Commissioners of Patents on the 4th August 1881.
FREDERICK WILLIAM COTTRELL, of 35, Calthorpe Street, in the City of London
THE MANUFACTURE OF MATERIAL
and County of Middlesex. "IMPROVEMENTS IN
TO FORM ARTIFICIAL IVORY, AND APPLICABLE ALSO AS A SUBSTITUTE FOR HORN,
INDIA
CORAL, MALACHITE, VULCANITE,
RUBBER, GUTTA PERCHA, AND FOR
VARIOUS OTHER PURPOSES."
This Invention relates to the production or manufacture of material to form
д substitute for horn, coral, malachite,
artificial ivory, and applicable also as
vulcanite, india rubber, gutta percha, and for various other purposes.
In the production of collodion, gun cotton, xylodine, and celluloid, it has
hitherto been the custom to act upon fibre by a mixture of sulphuric and nitric
acids, or by a mixture of sulphuric, nitric, and muriatic acids. The product
is soluble only in expensive liquids, such as sulphuric ether, nitro benzole,
camphorated solutions, alcoholic solutions, alone or in combination with hydro-
carbons, and further, it is objectionable from the dangerous condition in which it
is left.
According to my Invention, I produce a substance more tough and elastic than
that usually manufactured by the ordinary process, and one that is neutral and
free from nitrous compounds. For this purpose I take fibre either in the state of
raw or bleached cotton rags, esparto grass, paper, or the like, and submit it to the
action of the acid solution which I prepare as follows:-I take sulphuric acid, say,

page_text: of a gravity of 1840 to 1850, and this I place in a receiver. I also take nitrous
acid in its rough crude state, say, of a gravity of 1420 or thereabouts, and place in
it a retort in connection with the receiver, or in any other appliance suitable for
evolving and conducting the fumes in such a manner that the whole of the
sulphuric acid shall be well saturated by them. This may be effected by bringing
the retort or other vessel containing the nitrous acid to an elevated temperature,
say, by means of a water bath or of a sand bath placed upon a source of heat.
The nitrous acid should be brought to the boiling point and kept at that point
until the saturation of the sulphuric acid is sufficiently effected. I usually
combine twenty five parts of nitrous fumes with seventy five parts of sulphuric
acid, but I do not confine myself to these proportions, but vary them according to
my requirements, in some cases employing twenty parts of nitrous fumes to eighty
parts of sulphuric acid, and in other cases thirty parts of nitrous fumes to seventy
parts of sulphuric acid. This prepared acid can be used either in a cold state or
at a temperature not exceeding 95 degrees Fahrenheit.
The fibre to be acted upon is immersed in the acid, one gallon of the prepared
acid to one pound of the fibre being convenient proportions; it is then immediately
*expressed and allowed to stand from twenty minutes to one hour, by which time
its conversion has taken place. It is afterwards washed in a plentiful supply of
water to free it as much as possible from the acids, after which it is immersed in a
solution of borax or thoroughly washed in alkaline ley and dried. It is then fit
to be treated by the solvent, either for the manufacture of solid articles or for
solutions of any given substance or fluidity. The solvent I prepare for the solid
or rigid articles is alcohol, either alone or combined with a hydrocarbon, and this
I employ usually in the proportions of one pound of solvent to one pound of the
converted fibre.
Compounds to match any colour may be prepared. In the case of pliable
articles I use from 25 to 50 per cent. of an oil, that will combine with the alcohol
and remain in the material, thereby keeping it always pliable and soft.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Frederick William Cottrell in the Great Seal Patent Office on the
3rd February 1882.
:
FREDERICK WILLIAM COTTRELL, of 35, Calthorpe Street, in the City of London'
and County of Middlesex. "IMPROVEMENTS IN THE MANUFACTURE OF MATERIAL
TO FORM ARTIFICIAL IVORY, AND APPLICABLE. ALSO AS A SUBSTITUTE FOR HORN,
CORAL, MALACHITE, VULCANITE, INDIA RUBBER, GUTTA PERCHA, AND
VARIOUS OTHER PURPOSES."
FOR
This Invention relates to the production or manufacture of material to form
artificial ivory, and applicable also as a substitute for horn, coral, malachite,
vulcanite, india rubber, gutta percha, and for various other purposes.
In the production of collodion, gun cotton, xylodine, and, celluloid, it has hitherto
been the custom to act upon fibre by a mixture of sulphuric and nitric acids, or
by a mixture of sulphuric, nitric, and muriatic acids. It has also been proposed
to use a mixture of sulphuric, nitric, and nitrous acids. The product (which is
soluble in liquids such as sulphuric ether, nitrobenzole, camphorated solutions, or
alcohol, in combination with hydro carbons), is objectionable owing to the dangerous
condition in which it is left.
According to my Invention I produce a substance both tough and elastic, and
one that is soluble in alcohol alone. For this purpose I take fibre either in the
state of raw or bleached cotton rags, esparto grass, paper, or the like, and submit
it to the action of an acid solution which I prepare as follows:-I take sulphuric
acid, say of a gravity of 1840 to 1850, and this I place in a receiver; I also take
nitrous acid of the kind known commercially by that name (which is a solution of
peroxide of nitrogen (NO 4) in nitric acid, and which solution, for the purposes of
my Invention, should be a saturated solution), say, of a gravity of 1420 or there-
abouts, and place it in a retort in connection with the receiver, or in any other
appliance suitable for evolving and conducting the fumes in such a manner that
the whole of the sulphuric acid shall be well saturated by them. This may be
effected by bringing the retort or other vessel containing the nitrous acid by any
well known means to a sufficiently elevated temperature to drive off the nitrous
acid gas. The higher the temperature the more rapidly will this be effected, but
care must be taken not to drive over any nitric acid, and to this end it is advisable to
keep the temperature below, say, 132° Fahrenheit. The nitrous acid should be kept
at an elevated temperature as above until the saturation of the sulphuric acid is
sufficiently effected. I usually employ twenty five parts of the nitrous acid with
seventy five parts of sulphuric acid, but I do not confine myself to these pro-
portions, but vary them according to my requirements, for examples, in some cases
employing twenty parts of the nitrous acid to eighty parts of sulphuric acid, and in
other cases thirty parts of the nitrous acid to seventy parts of sulphuric acid. This
prepared acid can be used either in a cold state or at a temperature not exceeding
95 degrees Fahrenheit. The fibre to be acted upon is immersed in the acid, one
gallon of the prepared acid to one pound of the fibre being convenient proportions;
the fibre is then immediately taken out of the acid, pressed slightly, and allowed
to stand from twenty minutes to one hour, by which time its conversion has taken
place. It is afterwards washed in a plentiful supply of water to free it as much
as possible from the acids, after which it is immersed in a solution of borax or
thoroughly washed in an alkaline ley; after the excess of water has been removed
and the product dried it is then fit to be treated by the solvent, either for the
manufacture of solid articles or for solutions of any given substance or fluidity.
The solvent I employ for the solid or rigid articles is alcohol, either alone or combined
with a bydrocarbon (say, to seventy five parts of alcohol (specific gravity 920) to

page_text: twenty five parts of coal oil), and this I employ usually in the proportions of one
pound of solvent to one pound of the converted fibre. The same solvent is employed
for both fluid and solid articles; when required for fluid articles I use from 12 to
20 parts of solvent to one part of fibre.
Compounds to match'any. colour may be prepared. In the case of pliable
articles I use from 20 to .50 per cent. of an oil, such as castor oil, that will combine
with the alcohol and remain in the material, thereby keeping it always pliable
and soft.
Having described the nature of my said Invention, and the manner of carrying
it into practical effect, I would have it understood that what I claim is,
1. In the manufacture of a material to form artificial ivory, and for other uses,
as above specified, rendering fibre soluble in alcohol (with or without addition of
hydro-carbon) by immersing such fibre in a saturated solution of nitrous acid in
sulphuric acid, substantially as described.
2. The manufacture of material to form artificial ivory and for other uses, as
above specified, by the improved process hereinabove described.
In witness whereof, I; the said Frederick William Cottrell, have hereunto set
my hand and seal, this Second day of February, in the year of our
Lord One thousand eight hundred and eighty two.
FREDERICK WILLIAM COTTRELL. (L.S.)