Improvements in Explosive Compounds.
Year: 1896

page_text: This Print is in accordance with the Original Specification as it stands after
Amendment (under Section 11 of the Patents, &c. Act, 1883) as required by
the decision of the Comptroller General of the 26th day of July 1897.
Date of Application, 23rd Mar., 1896
Complete Specification Left, 21st Jan., 1897-Accepted, 27th Feb., 1897
Communicated from abroad by ALFRED NOBEL, of 59 Avenue Malakoff, Paris,
in the Republic of France, Chemist.]
Improvements in Explosive Compounds.
I ALFRED VINCENT NEWTON, of The Office for Patents, 6 Bream's Buildings,
Chancery Lane, in the County of London, Patent Agent, do hereby declare the
nature of this invention to be as follows:-
Various attempts have been made to produce explosive compounds, the
combustion of which would develope gases of sufficiently low temperature to offer
adequate security against igniting fire-lamp, when present in coal mines. Thus
far, the explosives obtained possess two great disadvantages, viz.: (1) their
combustion produces gases of a temperature sufficient to ignite fire-damp, and
consequently the safety obtained, due to rapid cooling of such gases by their
sudden expansion, offers only a relative, and very limited security; (2) such
explosives, which are all of the detonative class, are very dense, and act too violently
on coals to be blasted, thus producing a shattering effect (which it is desirable to
avoid), instead of a rending action.
The powder hereinafter described differs altogether from those now in use for
the aforesaid purpose, in as far as it can be used without detonative ignition, and
its being granulated, which has never hitherto been the case with powders of
that class. It is, in fact, a kind of gunpowder, which, when ignited, develops gas
of much lower temperature than is the case with ordinarily granulated blasting
powder.
In its simplest form, the novel powder is a kind of gun-powder, the charcoal of
which has been replaced by a combustible developing much more, and much cooler
gas, than charcoal, as, for instance, dextrine and which powder, in addition to such
substitution, is made to contain inert or active ingredients, which still more lower
the temperature of its explosive combustion. Such ingredients may consist of
bi-carbonate of soda or alum, or other suitable pulverized inert substance; or they
may consist of combustibles or oxidisers, such as dextrine, sugar, wood-pulp,
starch, nitrate of potash, added in excess over and above their chemical com-
bustion proportions, whereby they impede the explosive combustion, and greatly
lower the temperature of the gases developed by the explosion.
A good powder for the aforesaid purpose is produced by intimately mixing
100 parts of nitrate of potash, 12 parts of sulphur, 75 parts of dextrine, and
40 parts of bicarbonate of soda. On slightly moistening the mixed ingredients, a
mass is obtained which, after drying, is easily granulated. The invention is not
limited.to the aforesaid ingredients, and the proportions herein specified are meant

page_text: only to exemplify the mode whereby powders of such low combustive temperature
are obtained as will offer the greatest possible security against igniting fire-damp.
The chief characteristic features of novelty consist in lowering, by means herein
described, the explosive temperature of powders of the granulated class.
The aforesaid explosive compounds may be fired either by the sparks of a fuse,
as gunpowder is fired, or by detonative ignition, as used for high explosives.
When the latter ignition is to be used, chlorate of potash is a more suitable
oxidiser than nitrate of potash. The danger arising from the use of such chlorate
is removed by the combination therewith of the undermentioned typical materials,
and in or about the proportions stated :-
60 parts of chlorate of potash
40 parts of dextrine
50 parts of bicarbonate of soda; finely powdered, intimately mixed,
slightly moistened, dried, and granulated.
Whether ordinary or detonative ignition, and the aforesaid nitrate of potash or
chlorate class should be preferably used, will depend entirely on the nature of the
coals or ground to be operated upon. It will be understood that fissures, where
they exist, greatly retard the explosive combustion of all powders which are not of
the class called high explosives, and that the more or less solid tamping of a bore-
hole also exercises, in that regard, a very great influence. The best rule is
therefore to use the aforesaid nitrate of potash powders where the degree of
confinement necessary to the requisite development of their disruptive power can
be obtained, and the chlorate of potash powders aforesaid,
ignition has to be preferably used.
were detonative
be
Of course, pieric acid, pierates, ballistite, and such high explosives can
treated in the same manner as herein described in relation to nitrate and chlorate
of potash powders. By incorporating therewith coinbustibles in excess, or inert
substances, as heretofore described, and granulating the compound or compounds,
powders can be produced which, when detonatively ignited, exercise a similar
effect. It will be understood, however, that the granulation of such powders
permits of incorporating a percentage of inert substances intended to cool the flame
which, without such granulation, would impede the action of the aforesaid
detonative ignition, and cause the greater portion of such powder not to explode at
all. It will also be understood that granulation permits of greatly reducing the
volumetric density of the charge, thus tempering its shattering effect in blasting a
coal or any other material which ought not to be too much crushed; and offering,
besides, the advantage of great expansion inside the borehole of the gases of
combustion, whereby their temperature is much lowered, before meeting the outer
fire-damp atmosphere.
'
By simply mixing intimately gunpowder, when mealed, with combustibles 4
in excess; such as, for instance, dextrine or sugar, moistening with water con-
taining a little gum, drying, and granulating, a powder of the aforesaid properties
is produced which does not intrinsically differ far from those herein described.
Dated this 23rd day of March 1896
NEWTON & SON,
Agents for the Applicant.
Improvements in Explosive Compounds.
I, ALFRED VINCENT NEWTON of The Office for Patents, 6 Bream's Buildings,
Chancery Lane, in the County of London, Patent Agent, do hereby declare the 5

page_text: nature of this invention an in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
Various attempts have been made to produce explosive compounds, the combustion
of which would develop gases of sufficiently low temperature to offer adequate
security against igniting fire-damp, when present in coal mines. Thus far the
explosives obtained possess two great disadvantages, viz. (1), their combustion
produces gases of a temperature sufficient to ignite fire-damnp, and consequently
the safety obtained, due to rapid cooling of gases by their sudden expansion, offers
only a relative and very limited security; (2) such explosives, which are all of the
detonative class, are very dense, and act too violently on coals to be blasted, thus
producing a shattering effect (which it is desirable to avoid), instead of a rending
action.
The powder hereinafter described differs altogether from those now in use for
the aforesaid purpose, in that it can be used without detonative ignition, and that
it is granulated, which has never hitherto been the case with powders of that
class. It is, in fact, a kind of gunpowder, which, when ignited, develops gas of
much lower temperature than is the case with ordinarily granulated blasting
powder.
In its simplest form, the novel powder is a kind of gunpowder, the charcoal of
which has been replaced by a combustible developing much more gas, and much
cooler gas, than charcoal. The substituted combustible may be, for example,
dextrine, and the powder, in addition to such substitution, will contain inert or
active ingredients, which will serve still further to lower the temperature of its
explosive combustion. Such ingredients may consist of bicarbonate of soda or
alum, or other suitable pulverised inert substance; or they may consist of com-
bustibles or oxidisers such as dextrine, sugar, wood-pulp, starch, nitrate of potash,
added in excess over and above their chemical combustion proportions, whereby
they impede the explosive combustion, and greatly lower the temperature of the
gases developed by the explosion.
A good powder for the aforesaid purpose is produced by intimately mixing
100 parts of nitrate of potash, 12 parts of sulphur, 75 parts of dextrine, and
40 parts of bicarbonate of soda. On slightly moistening the mixed ingredients, a
mass is obtained which, after drying, is easily granulated. The invention is not
limited to the aforesaid ingredients, and the proportions herein specified are meant
only to exemplify the mode whereby powders of such low combustion temperature
are obtained as will offer the greatest possible security against the ignition of fire-
damp. From the foregoing explanation it will be understood that the chief
characteristic feature of the invention is the lowering, by means herein described,
of the explosive temperature of powders of the granulated class.
The aforesaid explosive compounds may be fired either by the sparks of a fuse,
as gunpowder is fired, or by detonative ignition, as used for high explosives. When
the latter ignition is to be used, chlorate of potash is a more suitable oxidiser than
nitrate of potash. The danger arising from the use of such chlorate is removed by
the combination therewith of the undermentioned typical materials, and in or about
the proportions stated :-
60 parts of chlorate of potash
40 parts of dextrine
50 parts of bicarbonate of soda, finely powdered, intimately mixed,
slightly moistened, dried, and granulated

page_text: therefore, to use the aforesaid nitrate of potash powders where the degree of
confinement, necessary to the requisite development of their disruptive power can
be obtained, and the chlorate of potash powders aforesaid, where detonative
ignition has to be preferably used.
Of course, picric acid, picrates, ballistite, and such high explosives, can be treated
in the same manner as herein described in relation to nitrate and chlorate of potash
powders. By incorporating with these high explosives, combustibles in excess, or
inert substances, as heretofore described, and granulating the compound or
pounds, powders can be produced which, when detonatively ignited, exercise, a
similar effect. It will be understood, however, that the granulation of such
powders permits of incorporating a percentage of inert substances intended to cool
the flame, which inert substances, without such granulation, would impede the
action of the aforesaid detonative ignition, and cause the greater portion of such
powder, not to explode at all. It will also be understood that granulation permits
of greatly reducing the volumetric density of the charge, thus tempering its
shattering effect in blasting coal or any other material which ought not to be too
much crushed, and offering, besides, the advantage of great expansion, inside the
bore-hole, of the gases of combustion, whereby their temperature is much lowered
before meeting the outer fire damp atmosphere.
By simply mixing intimately gunpowder, when mealed, with combustibles
in excess, such as, for instance, dextrine or sugar, moistening with water containing
a little gum, drying, and granulating, a powder of the aforesaid properties is
produced, which does not intrinsically differ from those herein described.
Having now particularly described and ascertained the nature of the said inven
tion, and in what manner the same is to be performed (as communicated to me
from abroad), I declare that what I claim is:-
In the manufacture of explosive compounds, the means above described for
reducing their explosive temperature, and thereby removing the risk attendant on
the use of explosives in the presence of fire-damp.
Dated this 20th day of January 1897.
NEWTON & SON,
Agents for the Applicant.