Process of Manufacture of Agglutinant Enamels or Cements.
Year: 1897

page_text: Date of Application, 28th June, 1897-Accepted, 31st July, 1897
COMPLETE SPECIFICATION.
Process of Manufacture of Agglutinant Enamels or Cements.
I, BENJAMIN JOSEPH BARNARD MILLS, of 23 Southampton Buildings in the County
of London, Patent Agent, do hereby declare the nature of this invention (a
communication to me from La Granitine Société Anonyme of 29 Rue du Pont de
l'Avenue, Laeken, Brussels, in the Kingdom of Belgium) and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
The process of manufacture of agglutinant enamels forming the subject of tlie
present invention is based on a particular composition and special mode of production
of a cement which not only constitutes on the surface of ceramic products a most
brilliant enamel, but also a powerful element of cohesion of foreign substances with
which it is mixed as agglutinant with a view to the manufacture of various articles
such as slabs, bricks, paving tiles, mouldings, statuettes &c.
The new enamel cement is based on a mixture of chloride of magnesium and of
magnesia (magnesite) treated in composition and according to such a process of
constitution that when used in a cold state and placed upon or between polished
surfaces, the product is entirely finished without necessitating any ulterior finishing
work, that is to say, the enamel issues with the most beautiful brilliancy and the
body of the object has the dry hardness of the most beautiful cut stone, of close and
crystalline texture giving rise to no sweating nor efflorescence which constitute
the inconveniences of the ceramic products having a base of chloride of magnesium
and of magnesite as hitherto known.
As above mentioned these extraordinary results are due to the composition and
above all to the mode of constitution of the new cement of which the following is a
detailed description.
In the first place a liquid is prepared consisting of pure water and of silicate of
soda of a density of from about 1° to 2° Beaumé.
In this liquid is dissolved the chloride of inagnesium until the density rises to
about 31 or 32° Beaumé.
Finally there is added to this solution sulphate of alumina until the density is
equal to about 32° or 33° Beaumé.
The liquid thus prepared is nixed in the proportion of about 55% of liquid and
about 45% of calcined magnesite to constitute the cement, with which can be mixed
at will a variety of foreign materials to be agglutinated according to the various
products to be made.
By mixing for example with 30% of the said cement 70% of sand, a paste is
obtained giving the most beautiful products of facing slabs, bricks or tiles, paving
slabs &c. By pouring this paste into moulds with polished bottoms, glass for example, and
allowing it simply to remain there until completely set it is when withdrawn a very
coherent product, very hard and of beautiful crystalline texture,, the surface of which
in contact with the glass or bottom of the mould presents an absolutely irreproachable
enamel similar to enamels produced by vitrifaction.
If it is desired to obtain enamels finer and of different color from that of the paste

page_text: itself, there is mixed with the cement mineral materials of the required color; for
example kaolin gives a very fine and very sparkling white enamel.
A sinal layer of this enamel is then placed on the glass bottom and on this is
poured the coarser paste which it is desired to enamel in white. It is the same for
any other given tint, the corresponding material to that of the enamel to be produced
is added to the fundamental cement.
It will be evident that the paste will be more or less fine in texture according to
the materials mixed with the coment and the products to be obtained, thus in order
to manufacture, paving slabs a mixture of the said cement and fine gravel, crushed
granite or porphyry &c. is advantageously employed; the surfaces of which also
leave the moulds euanelled notwithstanding the coarse material used to fill them.
In a word by the aid of the new cement any desired ceramic products can be
manufactured, cold and with enamelled surfaces, the quality of which entirely
depends on the added material and the exterior contour of the moulds employed to
produce them.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
The process of manufacture of a ceramic cement or agglutinant, which by cold
working produces a brilliant enamel, such cement or agglutinant being characterised 2
by a solution of chloride of magnesium; (of which the water of solution is, before
the introduction of the chloride of magnesium, carried to about 1° or 2° Beaumé
with silicate of soda and the final density of which is raised by about a degree with
sulphate of alumina until the combination marks about 32° to 330 Beaume) in
mixture, in a proportion of about 55% with magnesite or calcined magnesia.
2
HARRIS & MILLS,
23 Southampton Buildings, London,. W.C., Agents.