IMPROVEMENTS IN THE PRODUCTION OF ENAMELS OR VITRIFIED COVERINGS ON EARTHENWARE METALS Srave LVD ATHAD Cros CIZNOTA
Year: 1881

page_text: LETTERS PATENT to Charles William Heaton, Professor of Chemistry, of
Lessness Heath, in the County of Kent, and Thomas Bolas, Consulting
Chemist, of Chiswick, in the County of Middlesex, for an Invention of
"IMPROVEMENTS IN THE PRODUCTION OF ENAMELS OR VITRIFIED COVERINGS
ON EARTHENWARE
METALS Srave LVD ATHAD
Cros
CIZNOTA"
PROVISIONAL SPECIFICATION left by the said Charles William Heaton
and Thomas Bolas at the Office of the Commissioners of Patents on the
31st October 1881.
CHARLES WILLIAM HEATON, Professor of Chemistry, of Lessness Heath, in the
County of Kent, and THOMAS BOLAS, Consulting Chemist, of Chiswick, in the
County of Middlesex. "IMPROVEMENTS IN THE PRODUCTION OF ENAMELS OR
VITRIFIED COVERINGS ON EARTHENWARE, GLASS, METALS, STONES, AND
SUBSTANCES."
OTHER
According to our Invention we mix with one or more of the materials ordinarily
used, or which may be used in the production of vitrified enamels, a phosphorescent
substance or substances, such as will after exposure to light remain luminous for
some hours, and we put some of this mixture on the object to be enamelled, after
which we expose the said object to a heat sufficient in degree to melt or partially
melt the mixture.
The phosphorescent substance employed may be luminous powder, such as is
used in the manufacture of luminous paint according to the Invention, for which
Letters Patent, No. 4152, dated 7th of November 1877, were granted to the late
W. H. Balmain, or such as can be purchased from W. Puzey, of Aldermanbury
Postern, in the City of London, or from his agents, but we do not confine ourselves
to these particular phosphorescent substances; but we use any suitable phospho-
rescent substance, restricting ourselves however to those whose luminosity is of a
useful duration, that is, such as are available for the purposes of practical
illumination for several hours after exposure to light.

page_text: By "one or more of the materials ordinarily used, or which may be used in the
production of vitrified enamels," we mean any of the ordinary fusible materials or
fluxes used singly or admixed by potters and enamellers for the production of
glazes or enamels, but all mixtures containing lead, antimony, iron, tin, and other
substances which form dark coloured compounds with sulphur must be avoided,
unless such metals or other substances are only present in a very small proportion.
We prefer to use a mixture of the phosphorescent powder sold by W. Puzey,
with two thirds of its weight of pure and finely powdered fluoride of calcium, and
about one fifth of its weight of borate of calcium, but we do not restrict ourselves
to these proportions or to these substances. The above materials we mix in the
form of powder, which powder is either laid or spread on the article to be
ornamented, after which the heat necessary for fusion is applied, or it may be
mingled with water so as to form a kind of cream into which the articles may be
dipped, or with which they may be painted; when dry, they are fired as in the
previous case.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles William Heaton and Thomas Bolas in the Great Seal
Patent Office on the 28th April 1882.
"E
CHARLES WILLIAM HEATON, Professor of Chemistry, of Lessness Heatlı, in the
County of Kent, and THOMAS BOLAS, Consulting Chemist, of Chiswick, in the
County of Middlesex. IMPROVEMENTS IN THE PRODUCTION OF ENAMELS OR
VITRIFIED COVERINGS ON EARTHENWARE, GLASS, METALS, STONE, AND OTHER
SUBSTANCES."
According to this Invention we make a suitable mixture for forming a surface of
enamel that will, after exposure to the action of light, remain luminous some
hours in the following manner :-We mix with a phosphorescent powder having a
luminosity of considerable duration, such as that now ordinarily sold as "Puzey's
luminous powder," about twice its weight of pure and finely powdered fluoride of
calcium, or the double fluoride of aluminium and sodium, ordinarily known as
cryolite, or other similar fluorides, and about one-fifth of its weight of borate of
barium or other similar borate, such as borate of calcium, preferring the borate of
barium, but we do not restrict ourselves to these exact proportions. The above
materials we mix in the form of powder, which powder is spread on the article to
be ornamented, after which the heat necessary for fusion is applied. In some
cases the mixture may be mingled with water or some other neutral liquid, so as to
form a kind of cream into which the articles may be dipped, or with which they
may be coated; when dry, they are fired, as in the previous case. As Puzey's
luminous powder and other similar phophorescent powders contain sulphur, it is
necessary to take care not to apply the above mixture to any surface consisting of
or containing lead, iron, or any other metal, which at a high temperature forms
with sulphur a coloured compound. If the substance to be enamelled consists of
or contains any such metal, it must first be coated with a substance which does not
contain any such metal. Substances suitable for such preliminary coating are
well-known to and commonly employed by potters or enamellers, they are such as
felspar, phosphate of lime, clay, silica, and the like.
Having described the nature of the said Invention and the manner of performing
the same, we desire to have it understood that what we claim is,―
1. In the manufacture of enamel or vitrified covering for earthenware or other
substances, the combination of phosphorescent powder of the kind above referred
to with fluorides of metal, such as are above mentioned, so as to make said enamel
available for the purposes of practical illumination for several hours after exposure
to light, substantially as described.
2. The manufacture of enamelled articles of a novel and improved character by
the use of Puzey's luminous powder of the kind above specified, substantially as
described.
In witness whereof, I, the said Charles William Heaton, have liereunto set
my hand and seal, this Twenty fourth day of April, in the year of our Lord
One thousand eight hundred and eighty two.