An Improved Method of Ornamenting Glass.
Year: 1891

page_text: Date of Application, 13th Jan., 1891-Accepted, 7th Mar., 1891
COMPLETE SPECIFICATION.
An Improved Method of Ornamenting Glass.
I, GEORGE WASHINGTON MARTIN, of East Somerville, in the County of
Middlesex and State of Massachusetts, United States of America, Gentleman, 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 :-
Of the accompanying drawings forming a part of this Specification,
Figure 1 is a longitudinal sectional view of an incandescent lamp globe
ornamented in accordance with my invention.
Fig. 2 is a cross section on liner, r of Fig. 1.
Fig. 3 is a side view of a lamp shade, and
Fig. 4 a view of a flat sheet or pane of glass, both ornamented in accordance
with my invention.
This invention has for its object to provide an improved method of ornamenting
glass, and it consists in forming designs on smooth surfaced glass by cutting away
or removing portions of the smooth surface by any suitable method whereby the
portions acted on will be slightly roughened or dulled as compared with the ordinary
smooth surfaces of blown or pressed glass ware, as by etching, grinding, or by the
sand blast, leaving portions of the glass surface smooth and transparent, and then
applying a coat of metallic leaf or foil to the surface thus treated, the said metallic
foil presenting a brilliant or lustrous surface where it bears on the smooth portions
of the glass, and a non-lustrous surface where it bears on the cut away or roughened
portions, the result being an attractive ornamentation composed of the lustrous and
non-lustrous surface when viewed through the glass. The invention also consists
in applying to the outer surface of the metallic coating a protecting coat composed
of a thin silver white glaze applied in liquid form, the metallic coating and the
protecting coat thus applied being both so thin that the aggregate thickness of the
two coatings does not hide the configuration of the ornamentation on the glass, said
configuration appearing in relief on the outer surface of the protecting coating, so
that both sides of the article are ornamented. The nature of the outer protecting
coat and the inner metallic coat is such that they will not be dissolved by heat,
hence the ornamentation is durable and not liable to be detracted from by the use
to which the ornamented article is put when said article is the globe or bulb
of an electric lamp, or any other article which in its ordinary use is exposed
to heat.
In carrying out my invention, I take an electric lamp globe, or any other article
to be ornamented, and by any suitable process such as the sand blast, or by
etching, grinding, engraving, or the like, remove parts of the smooth surface or
"skin" of the glass to form comparatively rough or non-lustrous figures or areas of
any desired design. After carefully washing and drying the portion thus acted on,
I apply thereto with a soft brush, a thin film or coating of a tenacious transparent or
colorless fluid of a volatile nature, and upon this film, before the latter has time to
be evaporated, I lay a sheet or sheets of silver leaf or foil, employing as many
sheets or pieces as are necessary to cover the engraved surface. The metallic leaf
or foil is caused by the said adhesive film to adhere so closely and strongly to the
surface of the glass as to give the portions bearing on the smooth surface of the
glass, a brilliant lustre without the aid of mechanical pressure and friction, the said
adhesive film having an effect to draw or bind the foil closely against the surface
of the glass, and thereby give the inner surface of the foil the same lustre and
brilliancy that is produced by burnishing pressure applied externally. The parts
of the foil that bear on the engraved portions of the glass are given thereby a

page_text: silvered non-lustrous finish which makes a very desirable contrast with the lustrous
portions. When the frail and delicate nature of an incandescent lamp bulb is con-
sidered, and the impracticability of applying burnishing pressure to a coating of foil
thereon, on account of the danger of breaking the bulb, the value and importance
of the use of an adhesive film as the means for uniting the foil to the glass and
producing the intimate contact necessary without burnishing pressure will be
apparent.
In applying the pieces of foil care should be taken to cause the edge or edges of
the successive pieces to overlap the edges of the pieces already applied, so that
there will be no breaks in the continuity of the reflecting or coated surface.
After the metallic coating is applied as above described and is thoroughly dry
by the evaporation of the volatile properties of the adhesive coating, I rub a soft
brush lightly over the outer surface of the coating to remove the overlapping edges
of the pieces of foil, and then apply as a protecting coat or covering one or more
layers of a silver white liquid glaze, the color of which when dry or hardened,
preferably resembles that of the silver film.
When said protecting coat is dry and not tactile to the touch, I gradually heat
the article as coated to a baking heat, in an oven or by any other suitable means,
to harden the coatings applied as above stated, and at the same time anneal the
glass. After this the glass is allowed to cool gradually, the operation or process
being thus completed. The coating thus applied presents a bright silver color
on its external surface, which, in connection with the relief ornamentation
greatly adds to the beauty and attractiveness of the article, the silver exterior
being more desirable to the eye than the dark japan or other protective coatings
that have been used heretofore to protect metallic foil on glass. The coating
applied by my improved method will stand great heat without discoloration and
is extremely durable and tenacious, so that the article may be washed frequently
without injury to the coating. In case the article coated is to be subjected to a
high degree of heat in its ordinary use, the special heating operation above
mentioned may be dispensed with.
The improved method of ornamenting glass herein described is not necessarily
confined to incandescent electric lamp globes, although this is its particular design.
It may be applied to glass shades like that shown in Fig. 3, and to flat pieces or
panes of glass like that shown in Fig. 4.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The method hereinbefore described of ornamenting glass, the same consisting
in engraving one side of the glass and thereby forming a design comprising both
the smooth and the roughened or engraved portions of the glass, and then applying
metallic foil to the engraved side of the glass, as set forth.
2. The method herein before described of ornamenting glass, the same consisting
in engraving one side of the glass and thereby forming a design comprising both
the smooth and roughened or engraved portions of the glass, then applying metallic
foil to the engraved side of the glass, and finally applying a silver white glaze or
protective coating to the exterior of the coating of metallic foil, as set forth.
Dated this 29th day of December 1890.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.