New or Improved Process of Plating Clay with Glass, and in articles made in accordance therewith.
Year: 1892

page_text: COMPLETE SPECIFICATION.
New or Improved Process of Plating Clay with Glass, and in articles
made in accordance therewith.
A communication by THE CLAY GLASS TILE Co., of Corning, in the County, of
Steuben, and State of New York, United States of America.
:
I, WILLIAM PHILLIPS THOMPSON F.C.S. M.I.M.E. of the Agency for
Foreign Patent Solicitors 6, Lord Street, Liverpool and 6, Bank. Street Manchester
both in the County of Lancaster & 323 High Holborn in the County' of
Middlesex Civil Engineer 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:-
Hitherto in the applying of a silicic coating to articles of different kinds, various
methods have been adopted. for example: For covering metal surfaces and for.
some forms of pottery, coatings have been employed which come properly under
the term of enamels, suitable mixtures such as various metallic oxides and pure clay
and other substances being applied to the surface and then burnt or baked on. The
mixture is put on in a cold state and is set and fixed and becomes, by the action of
In other instances, a glaze is
heat, part of the substance of the article enamelled.
formed on the surface of clay, tiles and similar objects by sprinkling on the tiles
previous to baking, suitable mixtures, comprising usually common salt whereby a
silicic coating is formed on, and it may be in part, out of the substance of the tile.
And further, it is known that an imperfect clay when baked sufficiently may exude
a suitable glaze upon the surface of the clay due to the fact that the imperfections
in the clay are fusible. A true clay, absolutely pure, will not give out a glaze
because it will not melt.
It has also been known that molten glass will adhere with more or less tenacity
to burnt clay, as for instance, at the sides of pure clay retorts. But there has been,
prior to this invention, no attempt made to utilize this principle in the arts. As a
matter of fact, unless the process herein indicated as the subject of this invention
he followed, glass so adhering accidentally to clay objects, has hitherto in "cooling
presented an apparently useless structure so far as any ornamental or other purpose
is concerned.
While this improved process is capable of a great variety of applications and may
be carried out with widely different apparatus, the accompanying drawings will
serve to illustrate the invention.
In said drawings;
Figure is a top view of a glass-mould which may be used.
Figure is a sectional view of the same with a brick or tile in place and the
plunger raised.
Figure 111 is a perspective view.
Figure IV is an edge view, and
Figure Va perspective view of bricks on which the process has been used:
Figure VI is a sectional view of a mould showing a hollow tile therein.,
Figures VII and VIII are sectional and perspective views of said tile.'
0 The purpose of the present invention is to coat or plate clay objects, such as
bricks, tiles, etc. with glass of any desired thickness and design in such man that
the plating shall be strong and free from tracks. To this end, the bricks. tiles or
other objects are prepared of clay or clay composition of such nature as to have
substantia ly the same shrinkage in cool ng as the particular glass employed for
5 plating.
It may bé found that the composition of the clay would have to be altered

page_text: according to the composition of the particular glass employed. The surface of the
object which is to be coated may be plain or it may be moulded or otherwise formed
or provided with any suitable design. The brick or other object. a, is, prior to
being coated, heated to a high temperature. The coating b of glass is then applied
and compressed on to one or more faces of the brick or other object. In practice
it has been found best to place the heated brick or other object a in a suitably
shaped mould c, its sides projecting sufficiently above the brick to allow room for
the molten glass and plunger d, then to drop on the brick a suitable quantity of
molten glass and by depression of the plunger spread the glass over the surface
of the brick and cause it to adhere firmly to the brick. The brick is then removed
from the press and placed in a suitable annealing oven or kiln and allowed to slowly
cool when it will be found to be coated with an even plate of glass which firmly
adheres to the brick and has an entire absence of cracks.. Furthermore, the glass
is found when applied to clay by this process, to acquire great hardness, the action
being apparently analogous to the chilling of iron.
With glass composed of 300 lbs. sand, 200 lbs. oxide of lead, 100 lbs. carbonate of
potash, 20 lbs. nitrate of potash, 1 lb. borax; a clay composed of four parts of
burnt pot clay, three parts of raw pot clay and two parts of sand may be used as
having substantially the same shrinkage, but in general the selection of the clay
or clay-composition to accord with the shrinkage of the glass employed, must be
left to the intelligence of the workman and his knowledge of the shrinkage of the
particular articles he desires to use.
The under surface of the plunger d employed may be altered at pleasure so as to
impart to the exterior surface of the glass plate any suitable design. Different
colored effects may be obtained by adding suitable coloring matters to the glass
or to the surface of the brick or tile under the glass plate or to the composition of
the brick or tile or by any or all of these methods.. A fine effect is produced by
applying a main plating of clear or colored glass (see Figure IV) and coating
this with a thin film e of glass of any selected color which may be then cut,
or ground or engraved to impart any desired design or ornamentation (sec
Figure V).
.
Where hollow or annular tiles or those in the shape of a square ring are made
as shown in Figs. VI, VII and VIII, the central aperture may be closed
during the application of the plate by a supplementary block or die which may.
impart to the central portion of the plate any desired design or which may be
perfectly plain.
$6
""
The term "brick or tile" is employed in its most comprehensive sense to cover
any similar article without regard to its shape or to the art or purpose for which
it is employed, and the term compressed" is intended to cover any and all
means of applying the glass to the clay under pressure, whether it is done by a
plunger, rollers, forcing through dies or otherwise.
"
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 by
my foreign correspondent, I declare that what I claim is:
1. The process of manufacturing glass plated bricks, tiles and other articles,
which consists in forming the article of clay or clay composition of approximately
the same degree of contraction and expansion as the glass" employed, raising the
said article to a high temperature, applying to the surface to be coated glass in
a molten condition, compressing the molten glass on to the surface of the brick so
that the under surface of the glass will adhere to the clay, and finally annealing
the glass plated article, substantially as set forth.
2. A brick or..tile or other article composed of clay or clay composition and
glass compressed on the clay, said clay and glass being approximately of the
same degree of contractibility and expansion, substantially as set forth.

page_text: 3. A brick or tile or other article composed of a body of clay or clay com-
position formed with an opening through it such as fand a glass plate compressed
onto the face of said body and covering said opening, substantially as set forth.
Dated this 18th day of July 1892.
WM. P. THOMPSON & Co.,
Agents for the Applicant.