Improvements in the Production of Vitrifiable Colours, Enamels, and the like.
Year: 1899

page_text: Date of Application, 8th Nov., 1899
Complete Specification Left, 25th July, 1500-Accepted, 8th Sept., 1900
Improvements in the Production of Vitrifiable Colours, Enamels,
and the like.
WO, ANTOINE EDOUARD PEYRUSSON, Chemist, of 17, Rue du Petit Tour,
Limoges, France, and EMILE PEYRUSSON, Chemist, of 3, Place Denis Dussoubs,
Limoges aforesaid, do hereby declare the nature of this invention to be as
follows:-
Vitrifiable colours which are fusible at a low temperature and which are fired
at the temperature of the muffle-kiln are at present all composed of metallic oxides
or salts fused or mixed with fluxes which are analogous to glass and serve to
cause the adherence of, and impart a glaze to the colouring matter.
As these fluxes always contain a large proportion of lead salts which are very
deleterious, the use of such vitrifiable colours, especially when applied by dusting
or powdering, frequently leads to suturnism or lead poisoning of the operatives
often with fatal results.
We have discovered however, that it is possible to prepare vitrifiable colours
of which the fluxes, instead of having a base of lead salts, have a base of salts of
bismuth and we have succeeded in preparing a palette of perfectly vitrifiable
colours entirely free from lead, and which are thus absolutely void of the danger
to the operatives referred to. These fluxes may vary greatly in composition
according to the degree of heat at which they are to be fired, the kind of colouring
matter with which they are to be mixed and the tone of colour to be obtained.
We have found that in order to obtain good fusibility it is of advantage to intro-
duce into the composition a certain quantity of silicate or borate of lithium.
These fluxes may be formed of silicates or borates of bismuth either alone or
in admixture or mixed with other vitrifiable salts such as phosphates, tung-
states etc.
The following compositions are given simply by way of illustration:-
Silica
Boric acid or borax
Carbonate or nitrate of potash
Oxide of bismuth
Lithium compound
10 to 30 per cent.
10 to 60 per cent.
5 to 40 per cent.
20 to 80 per cent.
5 to 30 per cent.
It will be evident that the oxide of bismuth may be introduced into the
compositions in any form suitable for finally producing silicate, borate or other
vitrifiable salt of bismuth.
The colouring matters which may be fused or mixed with these fluxes are:
For blues. Oxide and salts of cobalt.
For yellows. Oxide and salts of uranium.
For greens. Compounds of copper and chromium.
For rose colours and purples. Purple of cassius.
For reds: Oxides of iron.
and generally all colouring matters now in use except those which contain lead.

page_text: These new colouring matters are capable of resisting the action of acetic
acid and of the gastric juice.
Dated this 8th day of November 1899.
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.
Improvements in the Production of Vitrifiable Colours, Enamels,
and the like.
We, ANTOINE EDOUARD PEYRUSSON, Chemist, of 17, Rue du Petit Tour,
Limoges, France, and EMILE PEYRUSSON, Chemist, of 3, Place Denis Dussoubs,
Limoges aforesaid, 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:-
―
Vitrifiable colours which are fusible at a low temperature and which are fired
at the temperature of the muffle-kiln are composed of metallic oxides or salts
fused or mixed with fluxes which are analogous to flint glass and servo to produce
the coherence of, and impart a glaze to the colouring matters.
As these fluxes always contain a large proportion of lead salts which are
very deleterious to health the use of such vitrifiable colours, especially when
applied by dusting or powdering, frequently leads to saturnism or lead poisoning
of the operatives often with fatal results.
We have discovered however, that it is possible to prepare vitrifiable colours
of which the fluxes, instead of lead salts, have a base of salts of bismuth and we
have succeeded in preparing a palette of perfectly vitrifiable colours entirely
free from lead, and which are thus absolutely devoid of all danger to tho
operatives. These fluxes may vary greatly in composition according to the degree
of heat at which they are to be fired, the kind of colouring matter with which
they are to be mixed and the tone of colour to be obtained. We have found that
in order to obtain good fusibility it is of advantage to introduce into the com-
position a certain quantity of silicate or borate of lithia.
These fluxes may be formed of silicates or borates of bismuth either separately
or in admixture, or mixed with other vitrifiable salts such as phosphates, tung-
slates etc..
The following compositions are given simply by way of illustration; -
Silica
Boric acid or borax
-
Carbonate or nitrate of potash
Oxide of bismuth
Lithium compound
10 to 30 per cent.
10 to 60 "
5 40
"
"
"
"
" "
5 30
"
"
"
20 80
»
It will be evident that the oxide of bismuth may be introduced into the coin-
positions in any form suitable for finally producing silicate, borate or other
vitrifiable salt of bismuth.
The colouring matters which may be fused or mixed with these fluxes are:-
For blues: -Oxide and salts of cobalt.
For yellows:-Oxide and salts of uranium.
For greens: Compounds of copper and chromium.
For rose colours, and purples: -Purple of cassius.
For reds. Oxides of iron.
and generally all colouring matters now in use except those which contain lead.

page_text: These new colouring `matters are capable of resisting the action of acetic
acid and the gastric juice.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, we declare that
what we claim is:-
The employment of compounds of bismuth (with or without the addition of
Bilicates or borate of lithia) as a substitute for lead compounds in the preparation
of vitrifiable colours, enamels glazes and the like.
Dated this 25th dov of July 1900
'
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Ohancery Lane, London.