Improvements in the Manufacture of Smokeless Powder.
Year: 1899

page_text: Date of Application, 24th June, 1899
Complete Specification Left 1st Feb. 1900-Accepted 5th May 1900
Date of Application, 24th June, 1899
Complete Specification Left 1st Feb. 1900-Accepted 5th May 1900
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Smokeless Powder.
We, RICHARD WILLIAM SMITH GRIFFITH, J.P., EARLE HERBERT DURNFORD,
Works Manager, and GEORGE HENRY WADSWORTH, A.R.C.Sc. (London), Tech-
nical Chemist, all of the Schultze Gunpowder Co., Limited, Eyeworth, near
Lyndhurst, in the County of Hants, do hereby declare the nature of this inven
tion to be as follows:-
The object of our invention is the production of a new smokeless powder
suitable for guns of any calibre.
In the process of purifying nitro-lignin we find that a certain percentage of
this substance becomes so finely divided that it approximates to a state of
impalpability and that this approximately impalpable material can be recovered
from the washing liquors so that it will settle down into a comparatively dense
condition. Therefore according to our invention we take a purified nitro
cellulose of any degree of nitration and reduce the same to an impalpable
condition thereby wholly or partially destroying its apparent fibrous structure,
either by a prolonged use of a rag engine or by other suitable means.
we extract from the finely divided nitro-cellulose thus obtained, the water used
in the above operation. This extraction of the water can be effected by centri-
fugal or other action, more or less water being extracted according to the
required consistency of the paste. We mould or press this paste into any
desired form and then dry the same.
Then
In drying, the moulded or pressed mass contracts and becomes more dense,
forming a hard material which we convert into grains, flakes, cords, ribbons,
pellets or the like. The production of this material according to our inven-
tion is thus accomplished without the aid of the solvents ordinarily used in the
manufacture of smokeless powders.
Before drying the pasty material we can incorporate with the same any sub-
stance which does not impair or interfere with the chemical stability of the..
product and which will serve for oxidation or for rendering the product less
hygroscopic or as a slowing or quickening agent or simply for limiting the
degree of contraction of the mass when drying; such substance to be retained
in the product or afterwards removed.
Dated this 24th day of June 1899.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.;
Agents for the Applicants.

page_text: nical Chemist, all of the Schultze Gunpowder Co., Limited, Eyeworth, near
Lyndhurst, in the County of Hants, do hereby declare the nature of this inven
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:―
The object of our invention is. the production of improved smokeless powders
suitable for guns of any calibre or for blasting purposes.
We are aware that in the process of purifying nitro-cellulose or nitro-lignin
with the accompanying cutting of the fibre, a small percentage of these substances
becomes so finely divided that it approaches to a state of impalpability. We
find that this approximately impalpable material when recovered from the
washing liquors becomes a comparatively dense substance which is sufficiently
hard and porous when dry to be suitable for the basis of smokeless powders.
Therefore according to our invention we take a purified nitro-cellulose or
nitro-lignin of any required degree of nitration which has been reduced by any
suitable cutting machine to such a degree of fineness that when made into a
paste with water and allowed to dry it becomes comparatively hard without
the use of any cementing material. This hardness and density may be regu-
lated by the degree to which the cutting process is continued when once the
natural cohesion of the fine particles is arrived at, and also by the application
of pressure.
We take the finely divided nitro-cellulose or nitro-lignin as described and
make it into a homogeneous stiff paste by extracting superfluous water and
using pressure if necessary. This we form into any desired shape such as grains,
flakes, cords, ribbons, pellets or the like and dry the same. The result is a
comparatively hard porous nitro-cellulose or nitro-lignin of any suitable shape
or density.
Before drying the pasty material we may incorporate with it any substance
or substances which do not impair or interfere with its chemical stability for.
rendering the product less hygroscopic or slower in combustion or for quickening
the combustion by oxidation.
Thus, for example, we take nitro-cellulose or nitro-lignin of any desired degree
of nitration having regard to the qualities of the powder which we propose to
produce and treat this in a pulping machine until it is reduced to such a fineness
as to pass
through a mesh of not less than 200 to the inch. This operation is
carried out in the presence of water, as is usual in purifying nitro-cellulose but
whereas for the purpose of purifying, it is sufficient to divide the nitro-cellulose
up until it will pass a 50 mesh the sub-division must for the present purpose
be carried much farther and no practically useful result can be reached until.
the particles are reduced to about the size above indicated. By carrying the
subdivision farther we produce a slower burning powder and can in this way.
obtain any desired grade of the finished article. For example to. produce. a
sporting powder giving standard pressures and velocities such as are yielded by
the..well known Schultze powder, we may take a nitro-cellulose or nitro-lignin
containing 12% nitrogen and divide this up until the particles will pass through
a mesh of 200 to the inch. We then draw off the superfluous water by means
of a filter press or other suitable appliance which brings the material into the
condition of a soft paste. This can then be moulded or granulated in the usual
way and subsequently dried in the manner commonly used in the manufacture
of nitro-cellulose powders. The ordinary rules as to size and shape of grain
apply to this as to the already known nitro-cellulose powders, which in its
technical properties it closely resembles. Our new powder, however, differs in
this important respect from the nitro-cellulose powders in present use that we
are able by varying the degree of comminution of the nitro-cellulose to produce
the hardness of grain and adjusted rate of combustion which have hitherto been
produced by the use of solvents. We are thus able to produce a cellulose
powder without the employment of hardening agents at all although of course
we may find it useful for adapting our powder to particular purposes to make

page_text: se as coating agents or otherwise of the materials commonly employed by
powder makers in the treatment of nitro-cellulose for the production of smokeless
powder.
We can employ a nitro-cellulose or nitro-lignin of a higher degree of nitra-
tion than 12% of nitrogen if a still more rapid ignition is required, or a lower
nitration if a slower ignition is required, the extent to which comminution is
continued remaining within the same limits.
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 process for the production of smokeless powders from nitro-cellulose
or nitro-lignin which consists in reducing the nitro-cellulose or nitro-lignin in
the presence of water to the finely comminuted condition herein before described
(the degree of fineness being determined with regard to the desired properties
of the resulting powder) bringing it by the extraction of superfluous water
into a plastic condition and forming the paste so produced into any required
shapes, then finally bringing it by drying into the condition of a hard dense
porous material with or without the addition of extraneous substance substan-
tially as hereinbefore described.
2. The hereinbefore described smokeless powder having for its basis finely
comminuted nitro-cellulose the fineness of which is adjusted with a view to the
grade of powder required substantially as herein before described.
a
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicants.