A METHOD OF PREPARING SET-OFF PAPER FOR THE USE OF PRINTERS
Year: 1878

page_text: LETTERS PATENT to Willian Stedman Gedge and Charles Hayward, respec-
tively of 90, Saint John Street, Clerkenwell, in the City of London,
Manufacturing Chemists, for the Invention of "A METHOD OF PREPARING
SET-OFF PAPER FOR THE USE OF PRINTERS."
Sealed the 7th February 1879, and dated the 9th October 1878.
PROVISIONAL SPECIFICATION left by the said William Stedman Gedge and
Charles Hayward at the Office of the Commissioners of Patents on the 9th
October 1878.
WILLIAM STEDMAN GEDGE and CHARLES HAYWARD, respectively of 90, St. John
Street, Clerkenwell, in the City of London, Manufacturing Chemists. " A METHOD
OF PREPARING SET-OFF PAPER FOR THE USE OF PRINTERS."
b
We treat the paper ordinarily used by printers for the purpose of protection
against set-off or any other kind of paper by damping the same with a solution
prepared by dissolving in alcoliol (in one or other of its various forms) or in wood
naptha, one or other or more than one of the group of gums or resins soluble in
such spirits respectively, and adding thereto a proportion of citronelle oil. The
paper thus treated is thereby rendered better resistant to the action of the printing
ink, and the substitution of clean set-off sheets for those in use is not so frequently
necessary as is the case with the paper at present commonly employed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Stedman Gedge and Charles Hayward in the Great Seal
Patent Office on the 8th April 1879.
WILLIAM STEDMAN GEDGE and CHARLES HAYWARD, respectively of 90, Suint
John Street, Clerkenwell, in the County of Middlesex, Manufacturing Chemists.
"A METHOD OF PREPARING SET-OFF PAPER FOR THE USE OF PRINTERS."
The said Invention relates to the preparation of paper to be used by printers for
the purpose of preventing the set-off of the damp impression produced by the type
upon the plate or cylinder of the printing press or upon clean sheets or other sheets
already printed. The ordinary paper at present used for such purpose is incapable
of receiving many set-off impressions without constant shifting and frequent
change, and such frequent shiftings and changes are a source of considerable delay,
trouble, and expense to printers. For the preparation of our improved set-off
paper we take ordinary paper similar to that at present commonly used by printers
for the purpose of set-off sheets, and by means of a brush or rollers or by dipping
or otherwise damp it with a solution composed as follows:-We take one or other
of the gums or resins mentioned in the table herein-after contained, and dissolve
the same in alcohol or methylated spirit, or wood naptha, or miscible naptha,
according to the proportions of gum or rosin and solvent given in the said table,
having regard to the thickness and nature of the paper to be treated. To the
solution so prepared we add a small proportion (2 fluid ounces to the gallon) of
citronelle oil, but this addition is not essential to the success of our Invention.
When either gamboge, thus, or rosin is selected as the material for solution we
prefer to add to the solution prepared as above directed about 1 lb. per gallon of
some harder gum in the said table, such as shellac.
The following is the table of proportions above referred to:-
P
All
MALL
W

page_text: alcohol (in one or other of its various forms and strengths) or in wood naphtha,
substantially in the manner and for the purpose herein-before specified.
In witness whereof, we, the said William Stedman Gedge and Charles
Hayward, have hereunto set our hands and seals, this Fourth day of
April, in the year of our Lord One thousand eight hundred and seventy-
nine.
W. S. GEDGE.
(L.S.)
CHA. HAYWARD.
(L.S.)