Year: 1888

page_text: I, CHRISTEN REES BONNE of 41 Eastcheap London E.C. Merchant do hereby declare
the nature of this invention and in what manner the same is to be performed, to he
particularly described and ascertained in and by the following statement :-
My invention has for its object to facilitate the work termed "stopping off" usual
in all trades where designs are produced on metal, glass, ivory and any other body by
Wherever in the present specification I use
means of etching or galvanic action.
the word "galvanize," I thereby mean the process of depositing through galvanic
action a metal on another body, which process is ordinarily called electro plating or
gilding, silvering, coppering etc. according to the metal thrown down.
According to my invention the designs to be etched or galvanized are engraved or
otherwise produced on metal, stone, wood, glue or any other body ordinarily used
for printing from and therefrom printed copies are made upon gummed or pasted
paper. The printing varnish which answers my purpose best is a light lithographic
printing varnish, to which has been added while heating 22% Burgundy pitch
[white resin] and 3% wax.
.
The prints are immediately or almost immediately after their production covered
with a finely sifted powder, which is prepared either from some acid resisting material
On all the printed parts the
such as resin, wax, asphalte etc. or from fluor spar.
powder adheres, and consequently the design becomes coated with the fragments of
resin, wax, asphalte etc. etc. or fluor spar, as the case may be. The prints thus
treated may be left for some time before they are used. For the purpose of trans-
ferring a design that has been "laid on" with powder of resin, wax, asphalte etc.
I place the paper with the picture side downwards on the metal, china, glass etc.
that I want to etch or galvanize, and moisten the back of the paper with a sponge or
other material, that has been dipped in warm water, or I press the paper firmly with
some hot dry body. The heat causes the resin, wax, asphalte etc. to stick to the

page_text: article on which it is to be transferred, and when afterwards immersed in the etching
or galvanic bath the acid and liquids are prevented by the resin, wax, asphalte etc.
from penetrating to and acting upon the places thus covered which is called in the
trade stopping off or stopping out. The paper is of course withdrawn leaving the
protective powder before placing the article in the etching or galvanic bath. It is
clear that I can also reverse the process and cause the drawing etc. to be printed on
the paper in such a way that the printers varnish and subsequently the protective
powder comes where the lines of the design are not, so that the design etc. would
remain unprotected and consequently that only would be acted upon by the liquors
in the galvanic bath. That is to say everything else but the design would be
"stopped off."
In cases where I use fluor spar as "stopping off" composition I use a somewhat
different manner for transferring it from the paper print to the article to be etched,
than above explained, where I used heat in some form or other. I find that fluor spar
is more successfully transferred by painting a gummying medium, such as a weak
resin and turpentine or pure alcohol, solution, either on the print or on the article to
be etched. The paper with the design covered with fluor spar powder is laid on
the article face downwards, pressed on the back with a damp sponge, when the
powder comes off and sticks to the article allowing the paper to be removed as
before.
I can as already mentioned prepare the protective "stopping off" powder from
a great many different materials, but the mixture and receipt which I mostly prefer
is as follows: 50 parts by weight of asphalte is melted in a water bath and under
continuous stirring 45 parts by weight of mastic and 5 parts by weight of wax
are added. This mixture is afterwards crushed, powdered and finely sifted.
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 covering with an acid resisting powder or fluor spar powder or both
combined of designs to be transferred to metal, stone, glass, china, wood, enamel,
bone, glue or other bodies, for the purpose of etching or galvanizing as herein
described.
2. The method of transferring the acid resisting powder from the print to the
article to be etched or galvanized by means of heat as herein set forth and
described.
3. The method of transferring the fluor spar, where fluor spar is solely used,
to the article to be etched or galvanized by means of a binding solution as herein
described.
4. The combination of the above mentioned claims.