A New or Improved Method of Treating a Disintegrated Slate Mixture for the Manufacture of Useful and Ornamental Articles.
Year: 1899

page_text: Date of Application, 22nd Dec., 1899-Accepted, 14th Apr., 1900
A New or Improved Method of Treating a Disintegrated Slate Mixture
for the Manufacture of Useful and Ornamental Articles.
I WILLIAM CHARLES BROUGHTON Hydraulic Machinist of 151 Tredworth Road
Gloucester 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:-
This invention relates to a new or improved method of treating a mixture of
disintegrated slate by impregnating the same with steam and subsequently
moulding or pressing the said mixture by hydraulic pressure into the various
forms on designs required for useful or ornamental purposes, such as mantle
pieces and the like.
In carrying out my improved process according to this invention I proceed as
follows:-
The waste or scrap slate is reduced to a fine powder; to this is added
10 per cent or thereabouts of whiting and the same quantity of sand, or the
whiting and sand may be added before the slate is powder. The mixture is
then passed through a disintegrator and after disintegration it is placed in a
"steam kettle" sufficient varnish being added to make it slightly moist. The
whole is then throughly impregnated with steam until it contains sufficient
moisture to hold or bind together the said substances when squeezed in the
hand.
The mixture is then transferred to a mould of the desired pattern and sub-
jected to hydraulic pressure of about 1,200 lbs
per square inch.
Shellac, copal or black varnishes are equally advantageous in the manufacture
of the mixture, and the "steam kettle" as used in the manufacture of feeding
cake, is the most suitable for the purpose.
When sufficienfly pressed the article so formed is taken from the mould and
placed in a store room or chamber heated to a temperature of about 200° F
where it is left until throughly hard, the time occupied for this purpose being
usually from about seven to fourteen days according to the size of the article.
The said article is then ready for enamelling or painting in the manner most
suitable for the requirements. The advantages of my invention over previous
methods are that by the addition of the above named substances viz whiting
and sand to the slate dust, the quantity of binding material required is reduced
to a minimun and the time occupied in drying is considerably shortened, the
whiting being of a much more binding nature than slate dust and the sand by
reason of its flinty nature, separating the particles and acting as a foundation
for the softer and more absorbent materials to cling to.
The articles thus produced have also a greater percentage of natural stone.
The process of steaming causes the binding material to become throughly
amalgamated with the solid substances, the heated moisture dissolving it in a

page_text: manner impossible with the dry process, and the pressed article leaving the
mould in a cleaner and more perfect form owing to the absence of imperfectly
amalgamated material which is invariably present in the dry method of mixing.
Having now particularly described and ascertained the nature of my said
invention and in what. manner the same is to be performed I wish it to be
understood that I am aware that useful and ornamental articles have previously
been made of powdered slate mixed with varnish or other resinous binding
material and subjected to heat and to pressure and I make no claim to such
process but I declare that what I claim is :-
(Claim 1) In the manufacture of articles from waste or scrap slate the applica-
tion of steam for the purpose of facilitating the amalgamation of the binding
material with the solid substances substantially as described.
(Claim 2) The process of treating a mixture of disintegrated slate, whiting,
and sand by adding thereto a varnish and impregnating the whole with steam
substantially as described and for the purposes specified.
Dated this 21st day
01
Llecom her
LXK
J. B. FLEURET,
Agent for the Applicant
5 Hatton Garden Holborn Circus London, E.C.
J. B. FLEURET,
Agent for the Applicant
5 Hatton Garden Holborn Circus London, E.C.