The Manufacture of a New Material Designed to Serve as a Substitute for Bone or Celluloid.
Year: 1890

page_text: Date of Application, 7th Aug., 1890-Accepted, 27th Sept., 1890
COMPLETE SPECIFICATION.
The Manufacture of a New Material Designed to Serve as a Substitute
for Bone or Celluloid.
I, WILLIAM MARSHALL CAMPBELL CALLENDER, of 101, Leadenhall Street, in the
City of London, Engineer, 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 the manufacture of a new material designed to serve as a
substitute for bone or celluloid and which I term "Lactite."
The Lactite" is produced by reducing casein (or the solids in milk) to a partly
soluble or gelatinous condition, by means of borax, or ammonia, or by other suitable
means and then mixing it with a mineral salt dissolved in acid or water or acid and
water, which liquid is subsequently evaporated.
In carrying out the invention I advantageously place 10 kilogrammes of casein in
a vessel, and incorporate it under heat with 3 kilogrammes of borax previously
dissolved in 6 litres of water. When the appearance of the casein becomes changed
I draw off the water, and the residue will then be of a consistency somewhat resembling
melted gelatine and while in this state I add 1 kilogramme of a mineral salt held in
solution by 3 litres of acid. Almost any of the salts of iron, lead, tin, zinc, copper or
other mineral salts which are soluble in acid may be used. The acid employed depends
upon the salt used, as only such acid should be used as will properly dissolve the salt.
The salt employed depends upon the exact colour required in the finished material.
In practice I have obtained good results by the use of acetato of lead and acetic acid.
The solution of the mineral salt in acid must be thoroughly incorporated with the
previous mixture of casein and borax: this is a matter of some difficulty but can be
accomplished in a mechanical mixer. When the mixture is effected the solid matter
will be found separated from the greater portion of the acid and water which should
now be drawn off. The solid matter should be subjected to great pressure to drive
out all possible moisture, and any moisture which may remain should be evaporated
under great heat or by other suitable means, the resulting product being the new
material. The new material may either be supplied in the form of sheets or rods, or
moulded in any form desired, and it can be coloured, as required, either by the
admixture of pigments or by aniline or other dyes.
The cost of the material may be lessened by the admixture of a certain proportion
of other substances such as precipitated lime or chalk or other similar substances
soluble either in the acids, in the casein, or in the borax and water.
Instead of rendering the casein soluble or gelatinous by means of borax I may
effect the same result by the use of ammonia or by any other suitable means.
The combination of the materials can be effected in many ways and I do not bind
myself to the precise details above described or to any exact process of manufacture
or proportions of the different ingredients used in such manufacture as these can be
varied, according to the exact use for which the "Lactite" is intended; for general
purposes, however, I find satisfactory results from the above described process,
proportions and ingredients, and they will sufficiently illustrate the subject of my
invention.
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 a new material designed to serve as a substitute for bone or
celluloid by reducing casein into a partly soluble or gelatinous state by mixing it with

page_text: mineral salt dissolved in acid, the free acid being subsequently evaporated, substantially
as herein before described.
2. In manufacturing the material as described in claim 1 the admixture of other
substances for the purpose hereinbefore described.
3. In the manufacture of the material described in claim 1 the use instead of acid
for dissolving the mineral salt, of water or of water in combination with acid.
4. The new material designed to serve as a substitute for bone or celluloid,
substantially as hereinbefore described.
Dated the 7th day of August 1890.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.