Improved Process of Producing Imitation: Terra Cotta.
Year: 1891

page_text: Date of Application, 14th Aug., 1891
Complete Specification Left, 8th Apr., 1892-Accepted, 11th June,..1892
PROVISIONAL SPECIFICATION.
Improved Process of Producing Imitation: Terra Cotta.
1, WILHELM SCHLEUNING, Architect of 24 Frobenstr. Berlin, Germany do
hereby declare the nature of this invention to be as follows :—
My invention relates to a method of producing an improved building material in
imitation of terra cotta or stone wares for ornamental purposes, and its object
is mainly to produce an effective imitation which shall also be impervious to
the effects of the weather.
For the production of imitation terra cotta, I employ terra cotta chips ordinary
bricks, chamotte, clinkers etc. in powdered form, so that by mixing the same 'any
desired colour can be obtained.
This powder which is generally coarse for larger objects and finely ground
for sinaller figures is mixed with burnt powdered gypsum and burnt slaked lime and
water, and mixed or worked up to a sort of cement mortar. It is then pressed ¡or
stamped into the desired form of mould and again removed from the same after
having become hardened.
The hardening process may be accelerated by adding burnt powdered, or
efforesced lime. A quantity of silicate of lime is thus produced (in consequence of
the hydraulic influence of silicate and therefore also burnt clay on lime) with an
excess of hydrate of lime, and a small amount of gypsum. As the latter forms a
part of the mixture, which is soluble in water, it is converted into sulphate
of barium and caustic lime, by impregnating the finished article-with baryta water,
and 'the caustic lime already present, as also that newly produced, combines with
the carbonic acid of the air to form carbonate of lime, in such manner that the
resulting product consists of a mixture of silicate of aluminium,-silicate of lime,
sulphate of barium and carbonate of lime.
It is obvious that I can add small quantities of suitable colouring agents to the
mixture, for producing various effects without departing from the nature of my
invention in
any way.
The conversion of the caustic lime into carbonate of lime can also be accelerated
by adding carbonic acid, for instance by introducing smoke gases or by impregnating
in a watery solution of bicarbonate of ammonia or potassium and thus the mixture
be caused to harden more quickly. After having been thoroughly dried the articles
may be made impervious to the atmospheric effects by means of waterglass or
caseïne lime solution.
Objects of a purely ornamental nature, such as plastics and ornaments in short
'such wares are never subject to rough use in their employment particularly interior
decorations may be moulded without the aid of any mechanical pressure. In such
cases, the moulds may be made of wax, gloucous substance; gelatine; gutta percha
etc., the process remaining otherwise the same.
The proportions in which the ingredients are mixed varies according to the
purpose for which the ware is intended as also to whether an accelerated drying of
the ware is desirous.
1001
RAYNER & CASSELL,
37, Chancery Lane, London, W.C., Agents for the Applicant..

page_text: Improved Process of Producing Imitation Terra Cotta.
1, WILHELM SCHLEUNING, Architect of 24 Frobenstrasse Berlin, Germany, 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:-
My invention relates to a method of producing an improved building material in
imitation of terra cotta or stone wares for ornamental purposes and its object is
mainly to produce an effective imitation which shall also be impervious to the effects
of the weather.
For the production of imitation terra cotta, I employ terra cotta chips, ordinary
bricks, fire proof bricks, clinkers etc. in powdered form, so that by mixing the same
any desired colour can be obtained.
This powder which is generally coarse for larger objects and finely ground
for smaller figures is mixed with burnt powdered gypsum and burnt slaked lime and
water, whereupon it is worked up to a sort of cement or mortar.
It is then pressed
or stamped into the desired form, or mould and allowed to harden, whereupon it may
be taken out of the said mould.
The hardening process may be accelerated by adding burnt powdered or
effloresced lime. A certain quantity of silicate of lime is thus produced (in
consequence of the hydraulic influence of silicate) and therefore also burnt clay or
lime with an excess of hydrate of lime and a small amount of gypsum. As the
latter forms a part of the mixture which is soluble in water, it is converted into
sulphate of barium and caustic lime, by impregnating the finished article with
baryta water, whereupon the caustic lime already present, as also that newly
produced combines with the carbonic acid of the air to form carbonate of lime, in
such manner that the resulting product consists of a mixture of silicate of aluminium,
silicate of lime, sulphate of barium and carbonate of lime.
It is obvious that I can add small quantities of suitable coloring agents, to the
mixture, for producing various effects, without departing from the nature of
my invention.
The conversion of the caustic lime into carbonate of lime can also be accelerated
by adding carbonic acid, for instance by the introduction of smoke gases or by
impregnation in a watery solution of bicarbonate of ammonia or potassium and thus
the mixture be caused to harden more quickly. After having been thoroughly
dried the articles may be made impervious to atmospheric influences by means
of water glass or a solution of cascine and lime.
Objects of a purely ornamental nature, which are never subjected to rough use
in their employment, such for instance as interior decorations, may be moulded
without the aid of mechanical pressure. In such cases the moulds may be made of
wax, glutinous substances, gelatine, gutta percha, etc. the process remaining
otherwise the same.
The proportion in which the ingredients are mixed varies according to the
purpose for which the article is intended or as to whether it is desired to accelerate
the drying of the same.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is performed, I declare that what I
claim is :-
:
A process for producing imitation terra cotta and ornamental stone wares, which
consists in mixing powdered terra cotta, clay, fire brick, porcelain and similar
substances, with burnt powdered gypsum, burnt slaked lime and water to form a

page_text: cement, then pressing or casting such cement into moulds, allowing it to harden and
finally treating the finished article with baryta water substantially as described.
Dated this 7th day of April 1892.
RAYNER & CASSELL,
37, Chancery Lane, London, W.C., Agents for the Applicant.