Employment of Trinitroresorcine as Smokeless Driving Powder.
Year: 1894

page_text: Date of Application, 19th May, 1894-Accepted, 1st Sept., 1894
COMPLETE SPECIFICATION.
Employment of Trinitroresorcine as Smokeless Driving Powder.
I, JULIUS HAUFF, of Feuerbach, Stuttgart, Germany, Manufacturer of
Chemical Products, 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:-
Trinitroresorcine is distinguished from picric acid by containing one atom more
of oxygen. This difference gives rise to a totally different behaviour of these two
bodies both in free spontaneous deflagration, and also with the aid of an initial
fuse in an enclosed space.
When picric acid is burnt on a platina plate, it evolves an intense smoke, and
leaves behind a strong carbonaceous residuum; in the case of oxypicric acid this
takes place without any trace of smoke being evolved, and without leaving the
carbonaceous residuum. The difference between the two bodies is more striking
when burnt in an enclosed space with the aid of a so called initial fuse. Picric
acid is, as is well known, when kindled by fulminate of mercury, the most powerful
explosive; it is quite otherwise with oxypioric acid. In order to inflame it, a
smaller quantity of the fulminate of mercury suffices than is required for the
detonation of pieric acid, and the effects of the explosion are contained within such
narrow compass, that the free trinitroresorcine can without anything further be
used as smokeless driving powder.
To arrive at a uniform ballistic effect, and for the requisite regulation of this
effect, it is necessary to bring the styphnic acid to a symmetrical form. The
granular form is easily obtained by recrystallising the styphnic acid with hot
alcohol, whereby large hard crystal crusts are obtained, which can easily be
mechanically crushed, and by sifting, can be changed into every requisite size of.
grain. The smaller the grain, the more explosive are the effects, and vice versa.
Another kind of granulation can be obtained by powerful hydraulic pressure of
the finely powdered styphnic acid moistened with water, and pulverisation of the
cake thus obtained through pressure, in a manner similar to the production of
black powder.
Through the gelatinising of styphnic acid by the familar gelatinising mediums,
and appropriate shaping into grains or lamina, an exceedingly high ballistic effect
can be obtained, which is greatly in excess of that of the well known smokeless
powder, without exceeding the permissible limits of the gas pressure.
By treating the styphnic acid powder in its appropriate form with solutions of
indifferent bodies e.g. paraffin, in solvents which in a cold temperature either do not
dissolve styphnic acid, or dissolve it very little, thus for example, alcohol and by
evaporating this solvent, I obtain a coating over each separate atom, whereby it is
intended that on shooting, the combustion shall divide itself, in many single
combustions whereby the duration of the combustion is increased, and thereby the
force of the explosion can be diminished as required.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is
The employment of trinitroresorcine as smokeless driving powder, either in
granular form which is obtained from crystallisation by alcohol, pulverisation aud
sifting, or in grains pressed in the manner of black powder, or by appropriate
gelatinising mediums brought to a colloidal form, grain or lamina, and covering the

page_text: single grains with a thin coating of indifferent bodies, for example paraffin, whereby
the burning goes on slowly and therefore the explosive force is diminished.
Deted this 10th day of Mov 1804
R. CORE GARDNER,
Patent Agent, 166 Fleet Street, London,
Agent for the said Julius Hauff.