Improvements in and relating to Refractory Incandescent Mantles or Hoods.
Year: 1899

page_text: Improvements in and relating to Refractory Incandescent Mantles
or Hoods.
I, GUSTAVE DAUBENSPECK, of 91, Listria Park, Stoke Newington, London, N.,
Incandescent Mantle Manufacturer, do hereby declare the nature of this inven-
tion to be as follows:-
My invention relates to the manufacture of refractory mantles or hoods,
which will become brilliantly incandescent under the heat of a flame, and con-
sists of improvements in the composition of the materials forming the same and
in the treatment of the mantle during manufacture to produce without the use
of any rare earths or metals, or of any salts of the same in its composition, a
cheap, very durable and very serviceable article.
I have found by lengthy experiments that the ordinary refractory materials
viz.salts, oxides or hydrates of calcium, which incandesce brilliantly under
great heat, may be rendered sufficiently tough and durable so as to retain their
form when applied as a deposit to filaments to form a light mantle when treated
by an acid to cause their chemical conversion in situ upon the supporting fila-
ment and such conversion can be effected without injuring their brilliancy under
incandescence, by the use of the materials and by the treatment during manu-
facture as hereinafter described.
To carry my invention into effect I prepare a strong solution of chloride of
calcium or chloride of lime which salt of calcium I prefer because it destroys
organic matter in the filament, and by dipping a purified filament or a frame
work of filaments therein, I obtain a coating of the calcium salt thereon in the
usual way.
After drying the filament or made up mantle I dip it again into a solution of
chloride of potassium and again dry.
I then prepare a final solution composed of a mixture of a salt of aluminium
(preferably nitrate of aluminium) nitrate of magnesium, nitrate of ammonium
and nitrate of potassium and super acidify the solution by the addition of nitric
acid so that free acid remains present. The filament or mantle is dipped in the
said solution, dried and again dipped and dried if desirable.
The colour shown by the incandescent filament or mantle depends upon the
proportions of the ingredients of the last solution. If a brilliant white incan-
descence is required, the addition of nitric acid is in excess. If a warmer and
more yellow light is desired, the nitrate of aluminium is added in excess and the
addition of nitric acid is diminished
The mantle being dried and completed, I apply to the head or upper part of the
mantle, a solution of nitrate of aluminium and nitrate of magnesium alone,
conveniently applied with a brush, to further strengthen the head of the structure.
even with some diminution of the incandesence of the material at that part.

page_text: For transport of the mantles before use, the mantles may be protected in the
usual way by a protective covering.
FELL & JAMES,
1, Queen Victoria Street, London, E.C.,
Agents for the Applicant.
Improvements in and relating to Refractory Incandescent Mantles
or Hoods.
I, GUSTAVE DAUBENSPECK, of 91, Listria Park, Stoke Newington, London, N.,
Incandescent Mantle Manufacturer, 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:―
My invention relates to the manufacture of refractory mantles or hoods, which
will become brilliantly incandescent under the heat of a flame, and consists of
improvements in the composition of the materials forming the same, and in the
treatment of the mantle during manufacture to produce, entirely without the
use of any rare earths or metals, or of any salts of the same in its composition,
a very cheap durable and serviceable article.
I have found by lengthy experiments that the ordinary refractory materials
viz.salts, oxides, hydrates, or chlorides of calcium, which incandesce brilliantly
under great heat, may be rendered sufficiently tough and durable so as to retain
their form when applied as a deposit to filaments to form a light mantle, when
treated by a solution having a free acid; to cause chemical conversion and
reaction amongst the ingredients "in situ" upon the supporting filament when
subjected to the heat of a powerful burner, which application of heat also serves
the purpose of burning and volatilizing the organic and carbonaceous matter of
the filament etc. Such chemical reaction is effected, without injury to the
brilliance of the ingredients under incandescence, by the use of the materials
approximately in the proportions and in the manner as hereinafter described.
To carry my invention into effect I prepare a strong solution of chloride of
calcium or chloride of lime, of which I prefer the latter, because it destroys
organic matter in the filament; and by dipping a purified filament or a frame-
work of filaments therein, I obtain a coating of the calcium salt thereon in the
usual way.
The filament or mantle of filaments is then dried.
I then prepare a final solution, composed of a mixture of a salt of aluminium
(preferably nitrate of aluminium) and nitrate of magnesium, and super acidify
the solution by, the addition of an acid, so that free acid remains present, of
which I find nitric or hydrochloric acids are the best.
The following proportions for this solution give a good incandescence to the
finished mantle, with great durability.
Nitrate of aluminium
Nitrate of magnesium
.74 parts
92 nonto

page_text: a warmer and more yellow light. is desired, the nitrate of aluminium may be
added in further excess; or sulphuric acid' may be used as the free acid,
with the effect of rendering the light blue, but more dull, and if sulphuric acid
be added to the above composition, the effect is a blueish but bright incandescence.
The filament or mantle is dipped in the above solution, dried, and again dipped
and dried, if desirable.
The mantle being thus dried, I apply to the head or upper part of the mantle,.
a solution of nitrate of aluminium and nitrate of magnesium alone, conveniently
applied with a brush to further strengthen the head of the structure, even with
some diminution of the incandescence of the material at that part.
The complete inter re-actions between the ingredients of my different solutions
as above described, producing a rigidity and stiffening of the mineral deposit
in situ upon the filament is effected by burning the dried mantle in the flame
of a powerful burner, which also serves to volatilize and burn away all organic
and carbonaceous matter of the filaments and mantle, leaving a tough mineral
ash of brilliant incandescent qualities under heat.
For transport of the mantles before use, they are protected in the usual way
by a protective covering.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
―
1st. The manufacture of an incandescent mantle or hood by dipping a filament
or framework of filaments, first, in a solution of a salt of calcium, drying the
same, further dipping the filaments into a super-acidified solution of the ordinary
alkaline earths such as aluminium and magnesium, drying the same, and finally
subjecting the mantle to a powerful flame for the completion of the inter re-
action of the ingredients in situ on the filaments, and the combustion and
volatilisation of the organic and carbonaceous matter of the frame-work, sub-
stantially as described.
2nd. In the manufacture of incandescent mantles, the fixing and toughening
of a calcium salt upon a filament or filament framework, by immersion in a
solution of magnesium and alluminium salts, super acidified by an added acid,
and by a final heating to incandescence of the dried filament or framework of
filaments, substantially as described.
3rd. In the manufacture of incandescent mantles, the composition of a solu-
tion for treating the filaments already covered by a calcium salt, consisting of
approximately 74 parts of an aluminium salt, 23 parts of a magnesium salt and
3 parts of nitric or hydrochloric acids, substantially as described.
4th. An incandescent mantle or hood, formed of a network of filaments reduced
to ashes by a powerful flame, and consisting of superposed layers of first a calcium
salt, and then a layer of super acidified mixed salts of aluminium and magnesium
caused to inter react one with another by a hot flame, substantially as described.
Dated this 7th day of November 1899
FELL & JAMES,
1, Queen Victoria Street, London, E.C.,
Agents for the Applicant.