Improvements in the Manufacture of Coloured Paper.
Year: 1890

page_text: ate of Application, 25th Apr., 1890-Accepted, 12th July, 1890
COMPLETE SPECIFICATION.
[Communicated from abroad by JAMES HARVEY CARPENTER, of 225, Dearbon Street,
Chicago, Illinois, Merchant, and CHARLES EDWARD O'HARA, of 45, West 47 Street,
New York, Manufacturer, both in the United States of America.]
Improvements in the Manufacture of Coloured Paper.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co. Patent Agents,
Southampton Buildings, in the County of Middlesex, 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:-
Heretofore coloured paper has been manufactured either by introducing colouring
matter into the pulp while in the beating engine or in the stuff chest, which necessarily
imparts a uniform tint to the pulp; or by printing upon the paper with coloured
inks.
In the improved process the colouring matter is applied so that it is distributed
upon or through the pulp while it is being transformed from pulp to paper,
whereby certain peculiar effects are produced, and it is especially adapted to con-
tinnous processes of paper making, such as are carried on in the machines known
as the "Foudrinier" and " Cylinder machines. In the Foudrinier machine the
pulp or stuff suspended in water is fed to a horizontally moving endless web of
fine wire cloth called the Foudrinier wire or making wire, which carries the layer
of pulp along and at the same time is shaken laterally to facilitate the inter-
locking or felting of the fibres, and during this operation the water is gradually
drained off through the meshes of the web until the pulp, which at the beginning
of, its journey was a mass of freely moving fibres suspended in water, has taken
on the consistency of wet paper, when it is delivered from the making wire to a
felt web to be pressed, dried and reeled.
In the cylinder machine the general mode of operation is the same, the making
wire being in the form of a cylinder partially submerged in the pulp instead of
a horizontally moving web. In this machine the water holding the pulp in
suspension escapes through the meshes of the submerged part of the cylinder
leaving a layer of pulp adhering thereto, which is lifted out of the vat by the
rotation of the cylinder.
I have found that the peculiar effects hereinafter described may be produced on
cylinder machines by adding colouring matter to the pulp in the vat at a point
adjacent to the cylinder and upon or just below the surface of the pulp so that
the colouring matter will be drawn toward the cylinder by the current of escaping
water and will not be generally diffused throughout the vat; in other words the
colouring matter may if desired, be applied to pulp while it is on the cylindrical
making wire, below the surface of the pulp in the vat, but when the colouring
matter is thus applied care should be taken to avoid such a general diffusion of
the colouring matter in the vat as might impair or destroy the peculiar effects
sought for.
When the colouring matter is applied to the pulp in the manner above described
at any point, it spreads in various directions from the point of application, and
when a more or less continuous stream or shower of colouring matter is used, the
forward movement of the machine will distribute the colour in an irregularly
shaded stripe or band without defined edges and with uniformity of pattern.
When two ог more streams or showers of colouring matter are used the
colours or tints are shaded and blended together, according as the points of
application are more or less widely separated, and by varying the relative position
of the points of application, and the amount and character of the colouring matter, an
endless variety of artistic effects may be produced.

page_text: In spite of this variety the product is always characterized by a peculiar softness of
shading or clouding of the tints and can readily be distinguished from coloured paper
made in the ordinary way, or from paper printed in colours or tints.
It is essential that the colouring matter should be applied to the pulp while it
contains water enough to cause a substantial diffusion to take place in order to soften
and shade the edges of the colour patches and blend them harmoniously, otherwise
unsightly strips and blotches of colour are produced with abrupt and ragged edges. I
have found by experiment that the most favourable results are obtained when the
colour is applied at or near the slices or sluices on the Foudrinier machines, and at or
just beneath the surface of the water in the cylindrical machines.
The colour may be added to the pulp by any means conveying it from a receptacle
and delivering it at the desired point; such, for instance, as a tube or tubes of greater
or less calibre leading from an elevated reservoir of colouring mitter, and terminating
when a Foudrinier machine is used, at or near the slices thereof, (that is to say at some
point on the Foudrinier wire before the pulp reached the suction boxes), and when a
cylinder machine is used, terminating at or just below the surface of the pulp and
adjacent to the cylinder.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed as communicated to me by my
foreign Correspondents I wish it understood that I claim :-
First. The process of manufacturing coloured paper which consists in applying
colouring matter to the stuff or pulp while it is on the Foudrinier wire of the
Foudrinier machine, or on the cylinder wire of the cylinder machine, and during the
formation of the pulp into paper, and subsequently drying and pressing the coloured
paper in the usual way, substantially as described.
Second. As a new article of manufacture paper coloured in shaded or clouded tints
by applying colouring matter to the stuff or pulp while it is on the Foudrinier wire
of the Foudrinier machine, or on the cylinder wire of the cylinder machine, and during
the formation of pulp into paper.
Dated this 25th day of April 1890
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.