OR IMPROVED PROCESS OF RAPIDLY ETCHING AND 'MATTING' OR ' 'DEADENING PATTERNS, DESIGNS OR ORNA- MENTAL EFFECTS, LETTERS AND THE LIKE ON GLASS OR OTHER VITREOUS SURFACES
Year: 1882

page_text: LETTERS PATENT to Edward Campbell Hancock, of Worcester, in the county
of Worcester, for an invention of "NEW OR IMPROVED PROCESS OF RAPIDLY
ETCHING AND 'MATTING' OR
'
'DEADENING PATTERNS, DESIGNS OR ORNA-
MENTAL EFFECTS, LETTERS AND THE LIKE ON GLASS OR OTHER VITREOUS
SURFACES."-A communication from abroad by Doctor Wilhelm Grüne, of
Berlin, in the empire of Germany.
PROVISIONAL SPECIFICATION left by the said Edward Campbell Hancock
at the Office of the Commissioners of Patents on the 2nd March 1882.
,
PROCESS
'
EDWARD CAMPBELL HANCOCK, of Worcester in the County of Worcester,
"NEW OR IMPROVED
OF RAPIDLY ETCHING AND MATTING' OR
DEADENING PATTERNS, DESIGNS OR ORNAMENTAL EFFECTS, LETTERS AND THE
LIKE ON GLASS OR OTHER VITREOUS SURFACES" (A communication from abroad
by Doctor Wilhelm Grüne, of Berlin, in the empire of Germany)
This invention relates to a new or improved process of rapidly etching and
matting" or "deadening" patterns, designs or ornamental effects, letters and the
like on glass or other vitreous surfaces.
Aqueous fluoric acid dissolves glass without exercising a visible influence upon
the remaining surface, leaving it approximately bright. Profiting by this peculiarity
in its corroding power, I avail myself of reserving materials which have before been
thought comparatively useless in consequence of their feeble resisting capacity.
These substances if placed upon glass in very thin layer, and even dried and hard
will yield in a few seconds to a solution of fluoric acid in water if the solution is
concentrated. Being simply used for the above purpose, very faintly marked and
bright results will be seen, but if I powder them when placed upon the surface of
the glass with very finely divided metal copal or other substances resisting the action
of the acid for a longer time and allow them to dry on after breaking them with
the acid, I obtain at once a more or less matted result.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Edward Campbell Hancock in the Great Seal Patent Office on
the 1st September 1882.
EDWARD CAMPBELL HANCOCK, of Worcester, in the County of Worcester.
NEW OR
IMPROVED PROCESS OF RAPIDLY ETCHING AND 'MATTING OR
'DEADENING PATTERNS, DESIGNS OR ORNAMENTAL EFFECTS, LETTERS AND THE
LIKE ON GLASS OR OTHER VITREOUS SURFACES." (A communication from abroad
by Doctor Wilhelm Grüne of Berlin in the Empire of Germany)
This invention relates to a new or improved process of rapidly etching and
"matting" or "deadening" patterns, designs or ornamental effects, letters and the
like on glass or other vitreous surfaces.
Aqueous fluoric acid dissolves glass without exercising a visible influence upon
the remaining surface, leaving it approximately bright. Profiting by this peculiarity
in its corroding power, I avail myself of reserving materials which have before
been thought comparatively useless in consequence of their feeble resisting capacity.
These substances if placed upon glass in very thin layers, and even dried and hard,
will yield in a few seconds to a solution of fluoric acid in water if the solution is
concentrated. Being simply used for the above purpose, very faintly marked and
bright results will be seen, but if I powder them when placed upon the surface of
the glass with very finely divided metal, copal or other substances, resisting the
action of the acid for a longer time and allow them to dry on after treating them
with the acid, I obtain at once a more or less matted result.
The practical advantage of this invention is that the corrosive action being very
quickly performed, those parts of the pattern required to be bright need not be
covered by any resists whatever.
Only feebly resisting substances being required which would be useless for the
ordinary method of procedure, not only all the well known methods of drawing
with a brush, pen, stylus &c can be used for putting the drawing on, but
impressions by all available methods of mechanical printing, typography,
lithography, glass, zinc and copper plate printing &c., as well as elastic stamping.
I also take advantage of thin and thick resists, using sometimes fine and coarse
materials for powdering, obtaining thereby a matted appearance of different density
or grain. In a drawing one can therefore obtain different and variegated shading
by the simple use of various materials in the same drawing.
In describing the modus operandi, I shall divide the process into two parts,
firstly, the simple process by which a matted pattern or drawing is put upon the
glass, and, secondly, the double process by which a bright pattern may be reserved
upon the glass, the ground work of the glass being matted or deadened.
SIMPLE PROCESS.
First, I put the drawing upon the object either by hand, transfer, or direct
printing, with almost any oil or varnish mixed with a little colour to render it
visible. I then powder it by means of a brush or a tuft of cotton-wool, or in other
suitable manner with pulverized metal copal or such similar substances.
I find what is known commercially as "bronze powder" very suitable for the
purpose.

page_text: DOUBLE PROCESS.
First, I either paint, draw or print the pattern in a material resisting fluoric
acid, such materials being well known. When dry I oil over the whole surface by
means of an ordinary printers composition roller with a greasy printing colour
or oil varnish, powder; treat with acid and wash, as described in the simple
process:
I then remove the resist pattern either with an alkaline solution, benzine,
alcohol, or like solvent.
Instead of applying the acid as a bath or by a brush, I may apply it in the
form of fine spray.
It will be understood that the word "glass" through this Specification must
also be taken to mean vitreous surfaces in general.
A very important feature of my invention is this, that whereas other patterns or
designs in vitreous etching with which I am acquainted are depressed below the
surface, my "deadened" or "matted" portion is raised above the surface, as may
be tested by running the finger-nail thereover.
The invention may be summed up as follows:-
The powdered materials allow the acid to flow between the particles, thus
leaving a series of minute spots or holes between each particle, caused by the acid
directly attacking the minute uncovered portions and indirectly attacking the
particles forming the resist (leaving them deadened), and thus a series of minute
and imperceptible holes or depressions produce the deadened effect.
I may arrange the pattern to be bright and incised while the groundwork is
dead and intaglio; or the pattern may be in intaglio and the groundwork bright
and incised.
If desired, I may print in a drying oil, powder with asphaltum, warm so as to
reserve the part under it, oil again, dust with the powder and treat with acid.
Having now described the nature of the said invention as communicated to me
from abroad, and the manner of performing the same, I would have it understood
that what I believe to be novel and original and desire to claim on behalf of the
said Doctor Wilhelm Grüne is
"
matted" pattern by the
Firstly. In vitreous etching the direct result of a
corrosion of fluoric acid, substantially as described.
Secondly. The process of vitreous etching or any mere modification or variation
thereof, substantially as described.
In witness whereof I the said Edward Campbell Hancock have hereunto set
my hand and seal this thirtieth day of August in the year of Our Lord one
thousand eight hundred and eighty two.
E. CAMPBELL HANCOCK. (LS.)