Improvements in the Production of Fluted or Corrugated Cardboard for Packing and other Purposes
Year: 1893

page_text: Date of Application, 18th Sept., 1893
Complete Specification Left, 15th June, 1894-Accepted, 21st July, 1894
PROVISIONAL SPECIFICATION.
Improvements in the Production of Fluted or Corrugated Cardboard
for Packing and other Purposes.
I JACOB FEIRABEND of Niedernhausen in Taunus, Rhenish Prussia, Manu-
facturer, do hereby declare the nature of this invention to be as follows:-
Heretofore, in the manufacture of fluted or corrugated cardboard which is used
for a great variety of purposes, and more especially as a packing material for
protecting articles from damage in transit, difficulty has been experienced in
preserving the corrugations, the material always having a tendency to return to
its original flat form. Attempts have been made to overcome this by covering one
side of the material with a strip or sheet of paper which prevented stretching but
rendered the material uneven.
According to my invention the material is built up of layers of paper which are
superposed and united by any suitable adhesive substance and corrugated or fluted
before the adhesive substance has dried and when consequently the small
displacement of the layers relatively to one another, which is necessary, is still
possible.
The paper in the form of endless sheets or strips, is led from rolls between
pressing rollers which cause the adhesive substance which is applied to one surface
of one of the strips or sheets, to unite the layers of material so as to produce a
single fabric which is then, while the adhesive substance is yet sufficiently moist,
passed between corrugating rolls. Several sheets of paper may be thus united, the
number of sheets depending on the weight of the paper and the thickness of the
cardboard to be produced.
In making the material from a pair of sheets, one of the sheets would be led over
a roller revolving within a paste trough, and the other beneath said trough, the two
meeting as they pass through the pressure rollers.
Dated this 18th day of September 1893.
By A. M. & Wm. Clark,
INADEND,
53, Chancery Lane, London, Chartered Patent Agents.
COMPLETE SPECIFICATION.
Improvements in the Production of Fluted or Corrugated Cardboard
for Packing and other Purposes.
I, JACOB FEIRABEND of Niedernhausen in Taunus, Rhenish Prussia, Manu-
facturer, 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, in the manufacture of fluted or corrugated cardboard for wrapping
or packing and other purposes, it has been necessary in order to preserve the
corrugated form and resist the tendency of the material to stretch and resume its,
original flat form, to apply to one side of the corrugated sheet, a flat or uncorrugated
backing sheet by which the corrugations are tied together so that flattening of the
corrugated sheet is prevented.

page_text: The object of this invention is to ensure the permanency of the corrugations and
prevent the tendency of the corrugated sheet to become flattened, without the use
of a backing sheet which detracts from the flexibility of the corrugated sheet, and
this is accomplished by making the sheet to be corrugated of two or more super-
posed layers of paper or thin cardboard, uniting them by an adhesive substance,
and subjecting them to the action of the corrugating rollers whilst the adhesive
substance is still moist, and consequently whilst the shifting of the one layer upon
the other, necessary in order that the layers may accommodate themselves to the
positions they occupy in the corrugations, is still possible. This shifting of the
one layer with regard to the other is consequent on the difference of radius of
curvature of the inner and outer layers at each bend or corrugation, the layers
alternately occupying the inner and outer positions as the curvatures are alternately
reversed. As, in the operation of corrugating, the layers are free to adapt them-
selves to the positions they occupy in the alternately opposed curvatures of the
corrugations and as, after being thus corrugated, the adhesive substance becomes
dry and retains them in the relative positions they have been caused to assume, the
product is a corrugated sheet of cardboard in which the convex portions of the
corrugations are not under tension and the concave portions under compression,
as is the case with cardboard corrugated in one thickness. The consequence is
that the corrugations thus produced are permanent, since the material naturally
tends to retain its corrugated form, as any flattening of the sheet would cause a
tension of the inner layer, and a compression of the outer layer, of the corrugation.
More than two layers may be thus united and corrugated, the number of layers
depending on the weight of the paper and the thickness of the cardboard to be
produced.
The accompanying drawing, forming part of this Specification, illustrates the
mode of carrying out the process of corrugating two superposed layers.
The continuous sheets of paper b, b, are uncoiled from reels a, the upper sheet
being led over a brush roller e revolving in a paste trough d and over a scraper e
by which the excess of paste is removed, whilst the other sheet passes beneath the
trough, and the two layers meet and pass together between the pair of pressing
rollers whereby the pasted and unpasted surfaces are pressed into close contact.
The united sheets then pass under and between the pair of corrugating rolls g
whereby the superposed sheets are subjected to the corrugating operation whilst
the paste is still moist and the united surfaces are free to slip on one another, and
from these rolls the corrugated sheet of cardboard is led off and slid along a table
until the paste becomes dry.
When more than two layers are to be thus united and corrugated, suitable
provision would be made for pasting the multiple layers.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The herein described process of making corrugated cardboard, which consists
in uniting two or more superposed layers of paper by means of adhesive material
and corrugating the combined sheets whilst the adhesive material is moist, so that
the layers are free to slip upon. each other and accommodate themselves to the
positions they occupy in the corrugations, substantially as specified.
2. Corrugated carlboard composed of two or more superposed and united layers
of paper whereof the corrugations are rendered permanent by the combined layers
having been corrugated whilst free to slip on one another so that they are not thereby
put into a state of initial tension and compression with regard to each other, as
specified.
3. The employment, for carrying out the herein described process of making
corrugated cardboard, of the combination of devices herein described, namely, the
pasting device, the pressing rollers for uniting the pasted sheets, aud the

page_text: corrugating rolls for corrugating them whilst the adhesive material is moist, as
specified.
Dated this 15th day of June 1894.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.