Note: Descriptions are shown in the official language in which they were submitted.
CA 02472851 2004-07-05
TITLE: I2E-ENF~T~~F,r~ ~ORP.I~OATEr,1'~ACI~A~IN'~' AIvlI3 INSULATION
hvlA TERIAL
FIELh OF TIDE INVENTIOhf
This invention relates to a corrugated packaging and ir,~sulation material.
In particular the present invention provides a protective cushioning
produ~t_for~ned by
corrugating a substrate and method of making same.
r~ESCRIP T ION OF THE PI1~IOI~ Al2 T
conventional corrugated cardboard has been used as packing material.
Various combinations of corr ugated cardboard with Styrofoam boards or bubble
sheeting are known. fIowevcr there is a need for a less expensive packaging
material
that is 100% recyclable and ewvironn~entaliy compatible.
s~tl~Al~~ OF TIN ~E~~rrI~~T
It is an object of the invention to provide a. re-enforced corrugated
product for use as protective packaging or insulation bars°ier.
It is a further object of the invention to provide a method of making a
corrugated product.
Thus in accordance with the present invention there is provided a
corrugated product comprising a corrugated substrate having a top surface and
a
bottom surface and a first sheet is larnanated to the points between the
corrugations of
the top surface. The substrate is selected from the group consisting of paper,
craft
paper or cotton Paper. The first sheet is selected from the group consisting
of paper,
3C craft paper, cotton Paper. A second sheet is laminated to the points
between the
corrugations of the bottom surface. The spaces between the corrugations in the
substrate and the first andlor second sheet material is filled with a
rec~rclable f~.lling
material that re-enforces the corrugated product. The racy clable filling
material is .
preferably selected from the group consisting of foamed starch, recycable
paper fiber,
wood fiber or natural plant fiber. 'I'he first and second sheets trap tlae
recyclable filling
material between the corrugated. substrate and the sheets to provide
additional
cushioning and insulation properties to the product over simply the
corrugations. The
corrugated product of the present invention can be used as a protective
cushioning
CA 02472851 2004-07-05
packaging material, an insulation barrier, shipping pallets, sound barrier or
re-enforced
boxes for shipping and product packaging. It is IOfl%recyclable and is water
resistant.
In anoth~,r e:nbo~;lirn.e~~t the in~~ention is directed to processes for
making
the corrugated products.
Further features of the invention will be described or will become
apparent in the course of the following detailed description.
l~ ~IE~IEF J~ESCRIPTI~I~ ~F T I-IE I~RA4~IN~aS
In order that the invention rna~r be more clearly understood, the preferred
embodiment thereof will r°~o~T be described in detail by way of
example, with reference
to the accompanying drawings, in which:
I5
Fig~zre I is a schematic end pla:ra ~riew of a re-enforced coaragated product
according to
the present invention.
Figure 2 is a schematic of an ernbodirnea~t of a process according to tl;le
present
2~ invention to form the corrugated products of Figure I.
DETI~ILEI~ DESCRIPTI~N ~F TI-IE PREFERREC~ ElI~IE~DIIvIEhTT
Referaing to Figure l, ~ corrugated product according to the present
25 invention is generally indicated ~.t 1. In the embadiment illustrated a
corrugated
substrate z, having a top surface 3 and a bottom surface ~., has all the voids
9 between
the con~zgations (flutes ~ filled with a recyclable, filler rr~aterial 6
preferably selected
from the group consisting of recycled paper fiber, wood f ~ber, natural plant
fiber or
foamed starch.. The fiber rn~aterial ~ can consist of one or amore of recycled
paper fiber,
3~ wood fiber, natural plant fiber or foas~ed starch alone or iir-~
v~orrabination.The top
surface 3 of the corrugated su~strate 2 is laminated with ~t first sheet'? and
the bottom
surface 4 is Ian2inated with a second sheet 8. In the embodiment illustrated
the
substrate z is selected froryz the group consisting of paper., craft paper or
Cotton paper.
The sheets 7,8 are preferab4y selected from the group consisting of paper,
craft papeA,
35 Cotton paper The sheets 7 and 8 trap the fiber material ~i -in the voids 9
between
corrugations 5 in the corrugated substrate and the sheets ?,8. The n3ore
strength
required the thicker the gauge of the paper selected for the substrate 2 and
sheets 7,8.
The corrugated product of the present invention can be used as a protective
cushioning
z
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packaging material, an insulation barrier, cushioned envelopes, void fill,
sound barrier,
carpet and flooring underlay or boxes for shipping and product packazging. It
is
recyclable and is water resistant.
Figure 2 illustrates sclmmaticaly one method of making the corrugated
products of Figure I. In Figure 2 three rolls 21, 22, 23 are shown. The roll
22 contains
the substrate 24 that will be corrugated to form the corrugated substrate 2.
Doll 21
contains the sheet 7 and roll 2 3 contains sheet 8. The sulL~strate 24 from
roll 22 is
threaded over- a heated idler rollers 25,26 that are capable of releasing
stearra into the
1Q substrate when it is a paper substrate being corrczgated. These heated
idler rollers
25,26 are preferably oiI heated. The substrate 24 is then fed through a pair
of male 27
and female 28 rotary dies to create the center flute 2 of the corr~igated
structure.
~Jhile substrate 24 is being corrugated, the sheets 7, 8 are drawn off rolls
21, 23. Sheet 7 passes over idle roller 29 and between heated idle rollers 3D,
31. Sheet
7 there passes under the extruder die 32 wl~erv a thin layer of extruded fiber
pulp andlor
foarnable starch is laminated to the sarface of sheet 7 and then around heated
idle
roller 38. As substrate 24 is cor~~ugated to form the flutes 5, the sheet '7
is fed between
nip roller 33 and corrugated sulsstrate 2 as it passes over female die 28.
Sheet '~ is
laminated only on the points 4Cl between corrugations 5 of the top surface 3r
The thin
layer of extruded fiber pulp argdlor foamable starch is still sticky after
being applied to
sheet 7. This enables the sheet material 7 to stick to the points 4~ on
substrate 2. As
the thin layer is tacky and it is run through nip roller 33 the thin layer
becomes thinner
at the points 4~ that it contacts the substrate 2 and will then not expand and
distort the
corrugations or flute 5 when subsequently heated.
~s the two ~.vebs i:ormed by substrate 2 and. sheet '~ continue around tlge
mold (female rotary die) 28 they exit and start to wrap around :rip roller 34
where the
second sheet 8 is introduced and adhered to the bottom of tl:e fluted
substrate 2.
The sheet material 8 is drawn from roll 23 under the extruder die 35
where a thin layer of extruded faber pulp ancUor foamable starch is applied to
the side
of the sheet 8 to be attached to the substrate 2. Sheet 8 then passes over
heated idle
roller 36. The sheet 8 continues, to pass with the lamination of substrate 2
and sheet 7,
through the nip rollers 34 and 3'~ and is laminated only on the points 4I
between
corrugations 5 of the bottom surf ace 4 of substrate 2. The thin layer of
extruded fiber
pulp andlor foamable starch is still sticky after teeing applied to sheet 8.
This enables
the sheet material 8 to stick to tlm points 41 on subs~rate 2. !~s the thin
layer is tacky
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and it is run through nip roller 34,3' the film layer beco~~es thinner ;at the
points 41
that it contacts the substrate ~ and gill then not expand and distort th~.e
corrugations or
flute 5 when subsequently heated.
The laminated structure ~2 nova proceeds through a heat source, in the
embodiment shown a ~ ( radio frequency) machine 43, that heats the paper and
fiber
to dry tl~e laminated structure 42 arid causing the foamable starch to
expand_(foam)
and fill in all the voids between the corrugation flutes 5 and the sheets 7,8
respectively. As the foanaabie starch is expanding the larn.inated structure
~2 travels
IO through cooled gauging nip rollers 44 that control the expansion and aid in
the drying
of the fiber filled structure 42. ''fhe rollers 25~, 30, 31, 25, .2~, 3f~ and
38 are all heated
to aid in the curing and setting of the fiber fiiler.
having illustrated and described a preferred embodiment of the
I5 invention and certain possl~le ~~odifications thereto, it should be
apparent to those of
ordinary skill in the art that ~e invention permits of' furths:r modification
irf
arranger~.ent and detail. ~~ll such modifications are cover; d by the scope of
the
lnventlon.
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