An Improvement in the Manufacture of Copying Paper.
Year: 1890

page_text: Date of Application, 6th Oct., 1890
Complete Specification Left, 26th Mar., 1891-Accepted, 9th May, 1891
PROVISIONAL SPECIFICATION.
An Improvement in the Manufacture of Copying Paper.
FREDERICK HAWKE Paper Merchant 2 Queenhithe Upper Thames Street
London E.C. does hereby declare the nature of this invention to be as follows:-
This invention has for its object the improvement of paper used for the purposes
of taking fac-simile copies of any documents written with ink, either by hand, or by
type writer, or printed or written in any other way, and commonly called "copying
paper." Ordinary unsized paper will when damped with water, take an impression
from specially prepared inks, called "copying inks," but as a rule fail to take
impressions from the ordinary or non copying inks," but when copying paper is
prepared with chemical ingredients, which combine with or act upon other chemical
ingredients in the ink, with which they come in contact, the result is that copies are
often obtained from "non-copying inks," where otherwise none would be obtainable,
& better blacker and more lasting copies are also obtained from "copying inks,"
even where such documents have been written some years previously, and which
have also been previously copied.
6
My invention may be carried out in any of the following ways, viz. by mixing
the ingredients with the pulp, in the course of manufacture, by running the paper
through the solution during or after manufacture, or by spraying the solution on to
the paper after or during manufacture.
The specific chemicals I employ for the purpose are perchloride of iron, and
bichromate of soda in combination. The proportions I employ for the attainment.
of the object in view are, to every 1000 lb. weight of dry pulp, I add 5 gallons &
5 pints perchloride of iron, and same volume of bichromate of soda solution.
The mixture is made by mixing equal volumes of perchloride of iron solution,
containing 12% of metallic iron & saturated solution of bichromate of soda
containing 8 lbs. to 10 gallons of water.
Dated this 6th day of October 1890.
FREDERICK HAWKE.
COMPLETE SPECIFICATION.
An Improvement in the Manufacture of Copying Paper.
FREDERICK HAWKE Paper Merchant 2 Queenhithe London E.C. 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 :-
This invention has for its object the improvement of paper used for the purposes
of taking fac-simile copies of any documents written with ink, either by hand, or by
type-writer, or printed, or written in any other way, and commonly called " copying
paper." Ordinary unsized papers will, when damped with water, take an impression
from specially prepared inks, called "copying-inks," but as a rule fail to take
impressions from the ordinary or "non-copying" inks, but when copying paper is
prepared with chemical ingredients which combine with, or act upon other chemical
ingredients in the ink, with which they come in contact, the result is that copies are
often obtained from "non-copying" inks, where otherwise none would be obtainable,
& better, blacker, and more lasting copies are also obtained from " copying-inks,
even where such documents have been written some years previously, & which have
also been previously copied.
My invention may be carried out in any of the following ways viz. by mixing

page_text: the ingredients with the pulp, in the course of manufacture, by running the paper
through the solution during or after manufacture, or by spraying the solution on to
the paper after or during manufacture.
The specific chemicals I employ for the purpose are perchloride of iron, and
bichromate of soda, in combination. The proportions I employ for the attainment
of the object in view are, to every 1000 lb. weight of dry pulp I add 5 galls. &
5 pints perchloride of iron, and same volume of bichromate of soda solution.
The mixture is made by mixing equal volumes of perchloride of iron solution,
containing 12% of metallic iron, & saturated solution of bichromate of soda
containing 8 lbs. to 10 galls. of water.
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;
The preparation of so called "copying papers" of any substance, by incorporating
with the pulp, or with the unfinished or finished paper, perchloride of iron and
bichromate of soda combined in the proportions above mentioned for the purpose
hereinbefore described.
Dated this oath ..
1001
FREDERICK HAWKE.