A NEW AND IMPROVED ASBESTOS MATERIAL, AND THE METHOD OF MAKING THE SAME
Year: 1881

page_text: LETTERS PATENT to Sydney Pitt, of Sutton, in the County of Surrey, for
an Invention of "A NEW AND IMPROVED ASBESTOS MATERIAL, AND THE
METHOD OF MAKING THE SAME." A communication from abroad by Henry
W. Johns, of the City of New York, United States of America.
PROVISIONAL SPECIFICATION left by the said Sydney Pitt at the Office of
the Commissioners of Patents on the 26th October 1881.
SYDNEY PITT, of Sutton, in the County of Surrey. A NEW AND IMPROVED
ASBESTOS MATERIAL, AND THE METHOD OF MAKING THE SAME." [A communi-
cation from abroad by Henry W. Johns, of the City of New York, United States
of America.]
"
"
Heretofore and before this Invention asbestos had been made into paper,
sheathing sheets," mill-board, and other manufactured material by being reduced
to fibre, mixed with hair, wool, or similar material, and felted or ground in an
engine into short fibres, either mixed with paper pulp and made into paper, or
pulped alone and made into sheets of paper, inillboard, sheathing, &c., as ordinary
paper pulp is treated.
The old processes of grinding into pulp in a paper
engine" necessarily renders the fibres so short that the product does not possess
the requisite strength. The sheets thus made are thin, and many layers are
required to make thick sheathing, heavy mill-boards, etc., which, being composed of
many thin sheets, is liable to be separated into the thin sheets, so that the sheet
thus made has very little adhesive strength. Wads, bats, or sheets of pure asbestos
fibre have heretofore been made, and are described in Letters Patent, No. 3376 of
August 19, 1880, but such bats are held together by the glutinous or binding
material applied to the surface thereof, and do not form a solid compact material
as is made by the Invention herein described.
This Invention consists of the method of making fibrous asbestos into a sheet,
sheathing, or material, in which the length of the asbestos fibre is kept unbroken,
the whole thickness of the material, however thick it may be made, being made
practically in one layer, so that it is not liable to become separated, as is the case

page_text: when made in different layers, thus making the material much tougher and more
serviceable.
The asbestos is reduced by ordinary methods into fine fibre, and preferably
carded, and the fibre deposited so as to form a wad or batting, the fibres of which
are intertwined with one another, wetting the wad or batting so made with water
or a glutinous solution and afterwards subjecting it to pressure, so that the
intertwined fibres will by being compressed become bent, interlocked, and fastened
together.
The fibres of asbestos, cryolite, and similar fibrous minerals are without barbs,
and when felted alone make a felt too weak to hold together, and it has been found
necessary to overcome this difficulty by sizing, &c., as described in the former
Patent, or to mix other holding matter with it.
The improved method is as follows:-
The asbestos or other fibrous mineral is separated into fibres preferably, as long
and fine as practicable.
The fibre is then thrown or deposited evenly over the surface of a table or apron
to any required thickness, forming a mat or bat, the fibres of which are crossed
and interlaced. The bat thus made of pure asbestos fibre is now subjected to a
spray or sprinkling of water or glutinous solution, and the bat thereby wetted is
afterwards subjected to pressure, so that the interlaced fibres which are bent about
one another are made thereby to hold together, and form a compact material of
almost any desired degree of solidity.
To properly carry out this method it is preferred to use a wire netting, covered
table, or drum, from the under or inside of which there is an air exhaust, so as to
make a current of air toward the table or drum. Near this table or drun a box or
table with a revolving picker drum or other suitable mechanical appliance is
arranged to hold the fibrous asbestos, through which an air current is passed so as
to blow a regular portion of the asbestos out of the box or table into the air current
which is going toward the table or drum covered with wire netting, against which
it is held by the ingoing air current, and may be so deposited to any desired
thickness, depending upon the quantity of fibre blown from the box and the rate
at which the wire netting covered table or drum is moving. The fibres may be
spread in a bat or mat by any other means without departing from the
Invention.
A jet of steam or spray of water or other suitable liquid is thrown upon the
fibres as they are drawn against the wire netting, so that the bat or mass will be
impregnated with dampness throughout; or if desired the water may be mixed
with glue or other glutinous or adhesive matter, or such mixture of water may be
sprayed upon the bat by a jet of steam or otherwise instead of pure water; or the
glutinous material may be otherwise employed during the process of forming the
bat. The moisture may if desired be applied to the bat after it is formed, the air
current carrying the moisture into the bat.
The bat thus prepared is run between rollers or otherwise subjected to heavy
pressure with or without heat, which, by compressing the bent or interlaced fibres
together, makes a tough and hard board, sheet, mat, sheathing, or form.
Through the bat as it is formed may be introduced wires or cords running in
various directions to give strength to the bat; when formed these wires or cords
become embraced in the bat, and become a part of it, adding greatly to the strength
of the material when finished.
The bat thus treated becomes under pressure a hard, firm, tough material
composed of asbestos fibre alone, excepting the fastening material sometimes intro-
duced. It may be made in sheets of any desired thickness, from a very thin
tissue or paper like sheet to a thick board or block, depending upon the quantity
of fibrous asbestos deposited in the bat.
The bat may be made into various forms, according to the mould on which the
fibre is deposited, or it may be pressed into any desired form by proper moulds
afterward applied to it.

page_text: The perforated screen may if desired be made of sheet or cast metal perforated
to allow the passage of the inductive currents, and capable of being used as one of
a pair of dies to properly press the bat formed on it surface into any desired shapes
or forms.
The material thus formed is capable of being made very hard by pressure
molded to various shapes, and of receiving a high polish by the application of
heated irons to its surface; is tough, firm, not liable to warp, may be colored with
dies or pigments, and is indestructible by fire.
The bat may have waterproofing material introduced in it, so as to form when
finished a water proof material, or the finished material may be waterproofed by a
coating of water proofening glue, india rubber, silicate of soda, oils, or resinous
matter may be introduced in the mat or bat, or applied to the material when
finished to give it greater strength and stability.
The bat or material may also be impregnated with glycerine or other nonvolatile
liquid, and thereby made pliable for special purposes.
The material may be fastened to the surface of wood, metal, or like material
as a veneering, and will protect against fire the surface to which it is so applied.
It may be applied to various other uses, for example, when inade in sheets as a
covering for roofs, steam boilers, and pipes, applied as paper or felt is now
applied.
When thicker it may be used as slates, sheathing boards, panels, partitions, and
in all places where boards are now used.
When still thicker it will form solid blocks for fire brick, fire walls, or like
uses.
It may be formed in moulds into pails, tubs, bowls, door knobs, mouldings, or like
uses.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Sydney Pitt in the Great Seal Patent Office on the 25th April
1882.
SYDNEY PITT, of Sutton, in the County of Surrey. "A NEW AND IMPROVED
ASBESTOS MATERIAL, AND THE METHOD OF MAKING THE SAME." A communi-
cation from abroad by Henry W. Johns, of the City of New York, United States
of America.
"[
"
Heretofore and before this Invention asbestos had been made into paper
sheathing sheets," mill board, and other manufactured material by being reduced
to fibre mixed with hair, wool, or similar material, and felted or ground in an
engine into short fibres, either mixed with paper pulp and made into paper, or
pulped alone and made into sheets of paper, mill board, sheathing, &c., as ordinary
paper pulp is treated. The old processes of grinding into pulp in a paper
engine necessarily renders the fibres so short that the product does not possess
the requisite strength. The sheets thus made are thin, and many layers are
required to make thick sheathing, heavy mill boards, etc., which, being composed
of many thin sheets, is liable to be separated into the thin sheets, so that the sheet
thus made has very little adhesive strength.
"
Wads, bats, or sheets of pure asbestos fibre have heretofore been made, and are
described in Letters Patent, No. 3376 of August 19, 1880, but such bats are held
together by the glutinous or binding material applied to the surface thereof, and
do not form a solid compact material, as is made by the Invention herein
described.
This Invention consists of the method of making fibrous asbestos into a sheet,
sheathing, or material, in which the length of the asbestos fibre is kept unbroken,
the whole thickness of the material, however thick it may be made, being made
practically in one layer, so that it is not liable to become separated, as is the case
when made in different layers, thus making the material much tougher and more
serviceable.
The asbestos is reduced by ordinary methods into fine fibre, and preferably
carded, and the fibre deposited so as to form a wad or batting, the fibres of which
are intertwined with one another, wetting the wad or batting so made with
water or a glutinous solution, and afterward subjecting it to pressure, so that the
intertwined fibres will by being compressed become bent, interlocked, and fastened
together.
The fibres of asbestos, cryolite, and similar fibrous minerals are without barbs,
and when felted alone make a felt too weak to hold together, and it has been found
necessary to overcome this difficulty by sizing, &c., as described in said former
Patent, or to mix other holding matter with it.
The improved method is as follows:-
The asbestos or other fibrous mineral is separated into fibres, preferably as long
and fine as practicable.
The fibre is then thrown or deposited evenly over the surface of a table or apron
to any required thickness, forming a mat or bat, the fibres of which are crossed
and interlaced. The bat thus made of pure asbestos fibre is now subjected to a
spray or sprinkling of water or glutinous solution, and the bat thereby wetted is
afterward subjected to pressure, so that the interlaced fibres, which are bent about
one another are made thereby to hold together and form a compact material of
almost any desired degree of solidity.
To properly carry out this method it is preferred to use a wire netting covered
table or drum, from the under or inside of which there is an air exhaust, so as to

page_text: make a current of air toward the table or drum. Near this table or drum a box
or table with a revolving picker drum or other suitable mechanical appliance is
arranged to hold the fibrous asbestos, through which an air current is passed, so as
to blow a regular portion of the asbestos out of the box or table into the air
current which is going toward the table or drum covered with wire netting,
against which it is held by the ingoing air current, and may be so deposited to any
desired thickness depending upon the quantity of fibre blown from the box, and
the rate at which the wire netting covered table or drum is moving. The fibres
may be spread in a bat or mat by any other means without departing from the
Invention.
A jet of steam or spray of water or other suitable liquid is thrown upon the
fibres as they are drawn against the wire netting, so that the bat or mass will be
impregnated with dampness throughout; or, if desired, the water may be mixed
with glue or other glutinous or adhesive matter, or such mixture of water may be
sprayed upon the bat by a jet of steam or otherwise instead of pure water, or the
glutinous material may be otherwise applied during the process of forming the bat.
The moisture may if desired be applied to the bat after it is formed, the air current
carrying the moisture into the bat.
The bat thus prepared is run between rollers or otherwise subjected to heavy
pressure, with or without heat which, by compressing the bent or interlaced fibres
together, makes a tough and hard board, sheet, mat, sheathing, or form.
Through the bat as it is formed may be introduced wires or cords running in
various directions to give strength to the bat when formed; these wires or cords
become embraced in the bat, and become a part of it, adding greatly to the strength
of the material when finished.
The bat thus treated becomes under pressure a hard, firm, tough material,
composed of asbestos fibre alone, excepting the fastening material sometimes intro-
duced. It may be made in sheets of any desired thickness, from a very thin tissue
or paper like sheet to a thick board or block, depending upon the quantity of
fibrous asbestos deposited in the bat.
The bat may be made into various forms, according to the mould on which the
fibre is deposited, or it may be pressed into any desired form by proper moulds
afterward applied to it.
The perforated screen may if desired be made of sheet or cast metal, perforated
to allow the passage of the inductive currents, and capable of being used as one of
a pair of dies to properly press the bat formed on its surface into any desired shapes
or forms.
The material thus formed is capable of being made very hard by pressure,
moulded to various shapes, and of receiving a high polish by the application of
heated irons to its surface, is tough, firm, not liable to warp, may be colored with
dyes or pigments, and is indestructible by fire.
The bat may have water proofing material introduced in it, so as to form when
finished a water proof material; or the finished material may be waterproofed by
a coating of water proofening glue, india rubber, silicate of soda. Oils or resinous
matter may be introduced in the mat or bat, or applied to the material when
finished, to give it greater strength and stability.
The bat or material may also be impregnated with glycerine or other non volatile
liquid, and thereby made pliable for special purposes.
The material may be fastened to the surface of wood, metal, or like material as a
veneering, and will protect against fire the surface to which it is so applied.
It may be applied to various other uses, for example, when made in sheets as a
covering for roofs, steam boilers, and pipes, applied as paper or felt is now
applied.
When thicker it may be used as slates, sheathing boards, panels, partitions, and
in all places where boards are now used.
When still thicker it will form solid blocks for fire brick, fire walls, or like
uses.

page_text: It may be formed in moulds into pails, tubs, bowls, door knobs, mouldings, or
like uses.
What I claim as new and desire to secure by Letters Patent is,--
First. The method herein described of making a sheet, sheathing, or material by
reducing asbestos to fine fibres, forming a wad, bat, or mass of asbestos fibres,
moistening the same and subjecting it to pressure, substantially as directed.
Second. As a new article of manufacture the herein before described material
formed of asbestos fibre formed in a bat or mass, afterward moistened and pressed
into a solid and compact form, substantially as specified.
Third. The combination with the material formed of asbestos fibre, as above
described, of strengthening wires or cords, either woven or placed therein during
manufacture or afterward attached, substantially as specified.
Fourth. The combination with the material formed of asbestos fibre, as above
described, of glycerine or like material to render it pliable.
Fifth. The combination with the material formed of asbestos fibre, as above
described, of a water proofing substance, substantially as specified.
Sixth. The material formed of asbestos fibre, as above described, as a veneering
for wood or metal, and in combination therewith, as specified.
In witness whereof, I, the said Sydney Pitt, have hereunto set my hand and
seal, this Thirteenth day of April, in the year of our Lord One thousand
eight hundred and eighty two.
SIDNEY FIT. (L.S.)