IMPROVEMENTS IN THE MANUFACTURE OF BRUSHES
Year: 1866

page_text: LETTERS PATENT to Alexander Parkes, of Birmingham, in the County
of Warwick, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE
OF BRUSHES."
Sealed the 7th December 1866, and dated the 11th June 1866.
PROVISIONAL SPECIFICATION left by the said Alexander Parkes at
the Office of the Commissioners of Patents, with his Petition, on the
11th June 1866.
I, ALEXANDER PARKES, of Birmingham, in the County of Warwick, do
5 hereby declare the nature of the said Invention for "IMPROVEMENTS IN
THE MANUFACTURE OF BRUSHES," to be as follows:-
This Invention has for its object improvements in the manufacture of
brushes. In order to manufacture the backs of brushes from plastic materials
or from materials which may be caused by pressure and heat, or other-
wise to be compressed into form, such as the material now well known as
"parkesine," clays, and other matters, a mould is employed, in one part of
which are a number of pins or projections corresponding with the number
of tufts of bristles or of other materials used, and in the other a series of
wires or mandrils is held at right angles to the pins or projections which
produce the holes on the under side of the back of a brush to receive the
tufts, while the mandrils or wires produce the horizontal passages for the
passage of the materials by which the tufts of bristles or of other materia's
are secured in such holes. When the material is used in a plastic state it is

page_text: introduced into the parts of a mould and is pressed therein so as to enter and
fill all parts of the space enclosed by the parts of the mould, and which are
not occupied by the projections or pins and the wires or mandrils used at
right angles to such pins or projections. When sheets of material capable
of being rendered soft and of taking form in moulds by heat and pressure, or
otherwise, are used, two or more layers or sheets of such materials are intro-
duced into moulds arranged as above explained, and subjected to pressure
and to heat, or have solvents or cement applied, so that when subjected to
pressure in moulds the sheets, layers, or parts may be made to combine and
take the form of the interior of the mould used, and have also formed therein
boles to receive the tufts and passages to receive the fastening materials.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alexander Parkes in the Great Seal Patent Office on the
11th December 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
PARKES, of Birmingham, in the County of Warwick, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of June, in the year of our Lord Ono
thousand eight hundred and sixty-six, in the twenty-ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Alexander Parkes, Her special licence that I, the said Alexander
Parkes, my executors, administrators, and assigns, or such others as I, the
said Alexander Parkes, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
THE MANUFACTURE OF BRUSHES," upon the condition (amongst others) that
1, the said Alexander Parkes, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next aud
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Alexander Parkes, do hereby declare
the nature of the said Invention, and in what manner the same is to be

page_text: performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
This Invention has for its object improvements in the manufacture of brushes.
In order to manufacture the backs of brushes from plastic materials or from
materials which may by pressure and heat, or otherwise, be compressed into
form, such as the material now well known as "parkesine," clays, and other
matters, a mould is employed, in one part of which are a number of pins or
projections corresponding with the number of tufts of bristles or of other
materials, and in another a series of wires or mandrils at right angles to the
pins or projections which produce the holes to receive the tufts; these man-
drils or wires produce the horizontal passages for the passage of the materials
by which the tufts are secured in their holes. When the material is used in
a plastic state it is introduced into the parts of a mould and is pressed therein
so as to enter and fill all parts of the space enclosed by the parts of the
mould, and which are not occupied by the projections or pins and the wires
or mandrils above mentioned. When sheets of material capable of being
rendered soft and of taking form in moulds by heat and pressure, or other-
wise, are used, two or more layers or sheets of such materials are introduced
into moulds arranged as above explained, and subjected to pressure and to
heat, or have solvents or cement applied, so that when subjected to pressure
in the moulds the sheets, layers, or parts may be made to combine and take
the form of the interior of the mould used, and have also formed therein
holes to receive the tufts and passages to receive the fastening materials.
The following is the manner in which I prefer to proceed:-The mould I
employ consists of a rectangular block of steel or cast iron with a parallel
passago through it of a sectional form corresponding with the back of the
brush to be moulded. Into this block fits a moveable bottom, the face of
which corresponds in form with the under side of the brush back, and has
steel pegs I screwed into it corresponding in number and position with the
tufts which the back of the brush is to receive after it has been mounted. On
the top of these pegs rest the longitudinal mandrils or wires to produce the
passages for the binding wires or other instruments by which the tufts are
secured; these mandrils or wires pass through holes formed for them in the
sides or ends of the mould block. At the top the mould is closed by a
plunger with a face suitable for forming the top of the brush back, or fre-
quently two such plungers are used, one to give a preparatory and the other
the finished form. If now I desire to form a brush back from parkesine, I
operate, by preference, as follows:-I cut out of a sheet of parkesine of
suitable thickness a piece of such a form as just to fit into the mould, and

page_text: then when the piece of parkesine and the mould are at the temperature about
of boiling water, so that the parkesine is slightly softened, I force the pre-
paratory plunger into the mould and so press the pegs through the material
and cause it thoroughly to fill the bottom. I prefer that the preparatory
plunger should have ribs on its surface which, when the plunger is at its
lowest position or pressed home into the mould, come in contact with the tops
of the pegs; the ribs should bo of a depth about equal to half the diameter of
the mandrils or wires which are now inserted into the grooves which the pre-
paratory plunger leaves; then another sheet of parkesine cut to shape and
softened like the first is laid in the mould, and a little softer parkesine, say, of
the consistency of hard putty, is placed between the two surfaces. The
finishing plunger is now forced into the mould, and thus the parkesine within
it is moulded to the form of a brush back, and when the mandrils or wires
are drawn out and the mould opened the brush back is turned out in one
solid piece.
The press employed should have sufficient power to apply easily a pressure
of at least one ton to each square inch of surface. Brush backs may be
produced in this manner either with handles or without.
Where it is desired that the tufts should be set at varying angles, the bottom
of the mould may be made in several parts so as to enable it to deliver, or
the pins may be moveable being placed in passages drilled at suitable angles
through the mould bottom, and then when the moulding is complete they may
be withdrawn from the under side; the tufts are inserted and secured in the
back in the ordinary manner.
In some cases, in place of operating as above described, I place in the
mould a mass of parkesini of the consistency of very hard putty and form it
at once by pressure with the finishing plunger, but the method first described
is preferable when working with parkesine.
When moulding brush backs in vulcanite I employ a mould tinned in
all parts, and I fill it with the india-rubber and sulphur compound, forcing
the compound into every part of the mould, and then to the mould and its
contents I apply heat, as is well understood, to change the compound into
vulcanite; afterwards the mandrils are drawn, and the mould being opened
the brush back moulding in one piece is turned out.
With tortoise shell or turtle shell I proceed in the manner first described
for parkesine, the shell being softened by heat in the manner usually practised
by workers in this material. The two pieces of shell unite under the pressure
without any cement; the article thus formed should be kept in the mould
until cold and hard, as otherwise it is liable to warp.

page_text: To mould a brush back from china clay I fill the mould with the clay in
the state of powder and nearly dry as it is ordinarily used for moulding by
pressure; I apply heavy hydraulic pressure, and afterwards draw out the
mandrils or wires and discharge the moulded brush back, which is then
finished by burning.
What I claim is the moulding brush backs with holes to receive the tufts
and other horizontal holes or passages to receive the wire or instruments by
which the tufts are secured, as above described.
In witness whereof, I, the said Alexander Parkes, have hereunto set
my hand and seal, this Eleventh day of December, in the year of our
Lord One thousand eight hundred and sixty-six.
ALEXANDER PARKES. (L.S.)