Note: Descriptions are shown in the official language in which they were submitted.
L52~
This invention relates to reinforced plastic sheet
material in both substantially planar and corrugated form and
to novel and improved methods and apparatus for manufacturing
such materials. The invention further relates to the lamination
of the aforesaid reinforced plastic sheets with other resilient
and cushioning materials which are particularly suited among
other applications for packaging articles for shipment.
This invention has as one of its objects the provision
of a novel and improved corrugated material formed of plastic
sheets and relatively stiff wire reinforcing elements which is
not only moistureproof but also may be made impervious to
gases and which will neither deteriorate nor weaken even when
constantly subjected to moisture. Depending upon the application,
the reinforcing elements may either be coated with a plastic or
uncoated and are preferably in the form of longitudinal and
transverse elements secured in spaced relationship to form a
structure affording substantial strength in the finished material.
Moreover, reinforcing elements of a variety of diameters and
plastic layers of various thicknesses may also be utilized
depending upon the strength and stiffness desired.
In accordance with a broad aspect of the present
invention there is provided a wire reinforced plastics material
characterized in that it comprises a corrugated structure
containing a plurality of wires in spaced parallel relationship,
at least some of the wires being corrugated, and a plastics
substance encasing-the wires, and in that a plastics overlaying
sheet is bonded to the crest portions on at least one side
of the corrugated structure.
lSZl
Another aspect of the invention involves an improved
plastic sheet material having longitudinal and transverse
wires embeaded therein to provide materially added strength
and atthe same time protect the wires from corrosion or
deterioration from water and ~ases. The sheet material may
be either a single layer or laminate or be in the form of a
corrugated structure with plastic layers on one or bokh sides
thereof.
15~ i
', .
Another object of the invention resides in the provi-
sion of novel and improved methods and apparatus for fabricating
xeinforced sheet and corrugated plastic materials having rein-
forcing elements of wire embedded therein.
Still another object of the invention resides in the
provision of a novel and improved method and apparatus for form~
ing a grid of longitudinal and transverse reinforcing elements
and embedding them in a plastic sheet.
A still further object of the invention resides in the
provision of a novel and improved method and apparatus for form-
ing a grid of longitudinal and transverse wires, corrugating
said grid and applying overlying layers of plastic to form a
relatively rigid board of appreciable thickness with substantial-
ly complete resistance to moisture.
A still futher object of the invention resides in the
provision of a novel and improved method and apparatus for form-
ing a c~rrugated board of plastic material having a corrugated
grid of longitudinal and transverse wires with overlying layers
of plastic sheets having wire grids embedded therein.
A further object of the invention resides in the
provision of an improved material comprising a wire reinforced
plastic sheet structure laminated with resilient and cushioning
materials.
This invention concerns the formation of improved
plastic materials wh~rein a reinforcing grid in either flat or
corrugated form is combined with plastic shee~ material to form
a reinforced plastic sheet or structure of appreciable thick-
ness wherein the grid i~ corrugated and lies between two sheets
of plast}c. Ihe corrugated grid may be coated with a plastic or
~3~
, ~151521
may be uncoated and the overlying plastic sheets may also be
reinforced with grids. The improved plastic materials may also
be laminated with resilient and cushioning sheet materials ~or
packaging and other purposes. Formation of the plastic materials
involves both an improved method and apparatus whereby the sets
of longitudinal and transverse elements of wire arranged in per-
pendicular grid-like relationship are embedded individually or ,~
simultaneously in plastic to form a reinforced sheet. The sets
of elements whether embedded or unembedded may then be corrugated
and enclosed by overlying plastic sheets sealed to the corrugated
structure. If desired, the overlying sheets may also be rein-
forced by wire. Resilient or cushioning material may also be
sealed to either the reinforced plastic sheet or the corrugated
structure.
The above and-other objects of the invention will be-
come more apparent from the following description and accompany-
ing drawings forming part of this application.
In the drawings:
Figure 1 is a diagrammatic view of the apparatus for
forming a plastic laminate having longitudinal wires disposed
therein.
Figure lA is an ~nlarged cross-sectional view of the
laminate with the reinforcing wires disposed therebetween
at an initial stage in the formation of the product;
Flgure lB is a cross-sectional view of Figure lA
taken along the line lB -lB thereof;
Figure lC is a cross-sectional view of the completed
laminate;
! 4
3~1~15~2~
Figures lB' and lCI correspond to Figures lB and lC
respectively and show more preci.~ely the relative thickness
of the plastic layers and reinforcing wire elements.
Figure 2 illustrates a modified embodiment of the
invention wherein the reinforced laminate is formed by the
utilization of an adhesive;
. Figure 2A is an enlarged cross~sectional view of the ',
laminate at an initial stage in the formation thereof;
i Figure 2B is a cross-sectional view of Figure 2A
taken along the line 2B - 2B of Figure 2A;
¦ Figure 3 is a plan view of one form of apparatus for
feeding wires into the laminates of figures 1 and 2;
j Figure 4 illustrates apparatus for producing a re-
inforced plastic sheet in accordance with the invention;
Figure 4A and 4B are cross-sectional views of two
stages in the formation of the reinforced plastic sheet pro-
duced by the apparatus of Figure 4;
Figure 5 illustrates still another embodiment of the
invention for forming a wire reinforced laminate;
Figure 5A is a cross-sectional view of an initial
stage in the formation of the laminàte by the apparatus shown
in Figure 5;
Figure 5B is a cross-sectional view of Figure 5A
taken along the line 5B - 5B thereof;
Figure 5C is a cross-sectional view of the complete
laminate formed by the apparatus of Figure 5t
Figure 6 is a modified.form of the apparatus shown
in Figure 5 utilizing an adhesive for forming the wire rein-
forced laminate;
-5-
~ - -----
(-
~.~L5~5Z~
Figure 6A is a cross-sectional vi~w of an initial
state in the formation of the laminate with the apparatus of
Figure 6;
Figure 6B is a cross-sectional view of Figure 6A
taken along the line 6B - 6B of Figure 6A;
Figure 7 illustrates an embodiment of the invention
for forming a laminate having both longitudinal and transverse .,
reinforcing wires;
Figure 7A is a cross-sectional view of the reinforced
laminate formed with the apparatus of Figure 7;
Figure 7B is a cross-sectional view of Figure 7A
taken along the line 7B - 7B thereof;
Figure 7C is a view similar to Figure 7B showing more
precisely the relative thicknesses of the plastic layers and
reinforcing wires.
Figure 8 illustrates apparatus for forming a plastic
laminate having both longitudinal and transverse reinforing
wires wherein the laminate utilizes an adhesive for joining
the layers;
Figure 8A is a cross-sectional view of the complete
laminate formed by the apparatus of Figure 8;
Figure 8B is a cross-sectional view of Figure 8A
taken along the line 8A - 8A thereof;
Figure 9 illustrates apparatus for foming a corru-
gated laminate material having reinforcing wires embedded
therein;
Figure 9A is a cross-sectional view of an initial
step in the formation o~ the laminate corrugated material pro~
duced by the apparatus of Figure 9; .
~ L5Z~
Figure 9B is a cross-sectional view of one form of
the completed laminate corrugated material produced by the
apparatus of Figure 9;
; Figure 9c is a cross-sectional view of a modified
i form of material shown in Figure 9B;
Figure 10 is a modified form of the apparatus shown
in Figure 9 wherein the outer layers of material are joined to ,
the corrugated material by means of an adhesive;
Figure lOA is a cross-sectional view of the material
produced by the apparatus of Figure 10;
Figure lOB is a cross-sectional view of a modified
form of material produced by the apparatus of Figura 10;
Figure 11 illustrates one procedure in accordance with
the invention for forming a wire grid for use in making corru-
gated reinforced plastic material;
Figure llA is a cross-sectional view of the wire grid
produced in accordance with the apparatus of Figure 11;
Figure 12 illustrates apparatus for forming a corru-
gated laminated material utilizing a wire grid, as for instance
the grid shown in Figure lLA;
Figure 12A is a cross-sectional view of the product
produced by the apparatus of Figure 12;
Figure 13 is a modified embodiment of the invention
for producing a laminated corrugated reinforced plastic material
in accordance with the invention;
Figure 13A, B and C are cross-sectional views of
successive stages in the formation of the product produced by
the apparatus shown in Figu~ 13;
1~
Figure 13D is a cross-sectional view of the completed
material formed by the apparatus of Figure 13;
Figure 13E is a modified form of material produced
by the apparatus of Figure 13;
,~ Figure 13~' is similar to Figure 13E showing the
thicknesses of the plastic layers and reinforcing elements more
, precisely.
Figures 14 and 15 show combinations of reinforced
plastic materials with cellular material and foam respectively;
and
Figures 16 and 17 show combinations of reinforced
¦ corrugated materials with cellular material and foam respectivel~ .
i As pointed out above, the improved product comprises a
plastic sheet or laminate having reinforcing wires di.sposed
therein or in the alternative may comprise a coated or uncoated
corrugated wire grid having layers of plastic on one or both
sides thereof. One method and apparatus for forming reinforced
plastic sheet material in accordance with the invention is shown
in Figures 1 and lA through C.- While the resultant product
produced by the apparatus of Figure 1 as well as the products
produced by the apparatus shown in ~ gfes 2, 4, 5 and 6 are
useful for many purposes, it will be shown that such products
are also usefùl in the formation of other types of reinforced
products in accordance with the invention for structural,
packaging and other similar applications.
Reference is now made to Figure 1 which illustrates
! one embodiment of the invention for fabricating a plastic
j, laminate ha~ing longitudlnal reinforcing wire,s embedded therein.
; 1~515~1
More specifically the apparatus includes a relatively large
heated drum 10 onto which the first film 11 which may be pre-
coated with a heat sensitive adhesive, is ~ed from the roll 12
and about roller 13. If desired, the roller 13 may also be
heated in order to increase the temperature of the film 11
just prior to its engagement with the drum 10. Immediately
following the application of the film 11 to the drum 10, "
a plurality of wires 14 are fed from a plurality of spools 15'
about r~lers 15 and 16 and onto the drum 10 and in overlying
relationship with film 11. The roller 16 is preferably provided
with a plurality of spaced, annular, wire receiving grooves to
maintain the desired wire spacing. The roller 15 which initiall~
spaces the w~res will be described in detail in connection with
Figure 3.
A second film 17, which may be pre-coated with a f
heat sensitive adhesive is fed from a roll 18 and about the
roller 19 in overlying relationship with the wires 14. The
~minate then proceeds about the drum 10 and sufficient heat
is applied to the laminate so that the two films can be sealed
one to the other with the wires therebetween. The temperature
of the drum 10-is, of course, related to the speed so that
adequate heat is transfexred to the plastic films. For instance,
if the drum 10 is rotating at a relatively high speed the tem-
pèrature of the drum can be at or even above the melting point
of the plastic film 11. On the other hand, should the drum be
operated at a low speed it would be necessary to maintain the
temperature of the drum slightly below the melting point of the
film 11.
, _g_ .
~15~:~
The two films are sealed one to the other by a pres-
. sure roller 20 preferably covered with a thin layer of poly-
tetrafluorethylene in order to prevent any possible adherence
I of the film to the pressure roller. The coating of the roller
20 is denoted by the numberal 20' and the roller 20 is preferably
-I cooled by engagement with a c-ooling roller 21 since it is im-
portant that the surface of the roller be maintained at a tem-
perature well below the melting point of the plastic and pre-
ferably below the embossing temperature. The roller 20 also
functions to remove the completedlaminate from the roller 10
whereupon it is fed about cooling rollers 22 and 23 and then
wound upon a spool 24. Figure lA shows a longitudinal section
!i through the lamina~e prior to the sealing of the films 11 and 17
one to the other. Figure lB shows a transverse view of the
laminate prior to sealing of the layers, while Figure lC is a
transverse view showing the two layers sealed one to the other
with the wires 14 disposed therein. In actual practice each of
the films is normally about one half the thickness of the wires
and a more accurate representation of the product is shown
in section in Figures lB' and lC.
: It is evident from the description of the apparatus
in Figure 1 that if it is desired to use a single film such as
the filM 11 and merely embed the wires 14 in the surface thereof
the wires may be coated with a primer such as sodium silicate,
for instance, or may be coated with a very thin layer of a
suitable plastic in order to facilitate adherence of the wire
to the film 11. In such a.case the wires whether including a
5~ 1
primer and the coating of plastic or just the plastic coating
itself would be fed onto the surface of the film ll as shown in
Figure l and thereafter the pressure roller 20 would force
the wires into the surface of the film.
. In feeding the wires 14 into overlying relationship
with the film 11 it may be desirable or necessary to m2intain .
a predetermined tension on the wires. For this purpose an
auxiliary roller 16' may be utilized which bears against the
grooved roller 16 and by the utilization of ~raking means on
the roller 16' the tension on the wires can be controlled
accurately.
A modified form of the invention shown in Figure l
is illustrated in Figure 2. In these fi.gures like components
are denoted by like num.erals, In the form of the invention
shown in Figu~e 2 the film ll is fed from a spool 12 and thence
onto a roller or drum 25 by means of an intervening idler roller
26. An adhesive contained in a trough 27 is applied to the
outer surface of the film ll by means of applicator rollers 28
and 29 whereupon the coated film passes through drying means
30 which may be in the form of an electric heater or in the
alternative may be in the form of a housing having an inlet 31
and an outlet 32 for feeding hot air through the housing and .
over the surface of the film. The dried film is then fed ab~ut
the rollers 33 and 34 to the drum lO. The remainder of the
process is identical to that of Figure l except that the tem-
perature.of the roller lO can be modified so that it will ade-
quately heat. the heat sensitive adhesive in order to provide
~l~lS15;Z1
a seal between the films 11 and 17. If desired, the film 17
may be coated in a manner similar to the film 11 so that the
rneeting surfaces of both films are coated with heat sensitive
material in order to facilitate-formation of a seal therebetween.
Figure 2A shows the inltial relationship of the wires 14, the
adhesive coated layer 11 and the non-coated layer 17. Figure 2B
is a cross-sectional view of 2A while Figure 2C shows the com-
plete structure with the adhesive 11' between the two layers.
It is evident that a wide variety of plastic materialsmay be used to form the sheets 11 and 17 and the selection of
the specific plastic would then, in a large part, depend on the
ultimate use for the product. For instance, it may be desirable
to use films having different characteristics as well as differ-
ent colors for decorative purposes and the films may either be
thermoplastic or thermosetting. When substantial strength is
desired particularly when the product is to be used in high
l temperature or structural applications a thermosetting plastic
'j is desired. Such a thermosetting plastic should, of course,
have a thermoplastic stage and then ultimately assume a thermo-
setting stage in the final product. It is also evident that the
plastic layers may have substantial flexibility for certain
applications while in other applications relatively rigid
plastics may be utilized.
In providing a product for specific application to
the packaging industry, pla~tics such as polyethylene, poly-
styrene, high density polyethylene, polypropylene, as well as
the polyamides and the polyesters are probably the more desirable
plastics that can be used.
.
~11515Zl
While the wires 14 may be guided onto the drum 10 in
any suitable manner, one form of apparatus which may be used
for this purpose is illustrated in Figure 3. In this figure
the roller 15 which guides the wires onto the roller 16 is pro-
vided with a plurality of closely spaced discs 35 which maintain
the spacing between the wires 14. The wires are fed from a
plurality of spools 15' through a series of guides 36 which
lead the wires between the discs on the roller 15. With this
arrangement the roller 16 ' would be provided with a resilient
surface and bear against the wires 14 while on the roll 16.
With such an arrangement tension would effectively be controlled
and it would not be necessary to rely solely on the friction
of the wires with the roller 16 in order to control the tension.
Figure 4 iIlustrates a further modification of the
invention wherein a plastic material is extruded directly onto
a drum and in contact with a plurality of longitudinally dis-
posed reinforcing elements such as wires. In this embodiment of
the invention, drum 37 is preferably cooled by the circulation
of water or other suitable coolant therethrough and a plurality
of wires 14 are fed from a plurality of spools 15' via the
roller 16 to the surface of the drum 37. The drum 37 may or may
not have a plurality of fine grooves for the receipt of the
wires 14. In most cases however it would not be necessary to
groove the clrum provided adequate tension is maintained on the
wires. Immediately after feeding the wires onto the drum 37
a plastic material 38 is extruded onto the drum by an extruder
39 which may preferably be a straight-die extruder. Since the
plastic extruded onto the surface of the drum is at a very
~1'.152i
il high temperature it will surround the wires as illustrated in
Figure 4A and then will gradually cool until it reaches the
take-off roller 40. The roller 40 is cooled in order to reduce
the temperature on the sheet so that it can be fed about the
roller 41 and then wound on spool 42. ~he complete product
is shown in Figure 4B and is then ready for either further
processing or direct use for the desired purpose. The form of
the invention shown in Figure 4B is substantially identical to
the product previously described in connection with Figure 1
wherein a single film 11 is utilized and the wires 14 are em-
bedded in the surface of the film. It is also understood in
connection with Figure 4 that the wires 14 may be either coated
¦ or uncoated as desired.
A further embodiment of the invention is illustrated
in Figure 5. In this embodiment of the invention a film 43,
which may be pre-perforated, is fed from a spool 44 about a rolle~
45 onto a drum 46. Immediately following the application of the
film 43 a plurality of wires 47 are fed from spools 15', about
rollers 48 and 48' and onto the surface of the perforated film
43. The rollers 48 and 48' correspond essentially to the rollers
15 and 16 of Figure 1. A second unperforated film 49 is fed
¦ from a spool 50 about a roller 51 and into overlying relation-
~' ship with the longitudinally disposed wires 43. The structure
!i f the product at this point in the process is shown in Figure
5A which illustrates the relationship of the films 43 and 49 with
the wires 47 disposed therebetween. The perforations in film
43 are denoted by the numeral 43'. Figure 5B i5 a cross-
sectional view of Figure 5A.
~ 1 1 51521
The laminate denoted by the numeral 53 then moves
downwardly between heaters 52 and about a roller 54 which has
vacuum ports distributed through~ut the surfa~e thereof and is alc o
cooled by the circulation of the coolant therethrough. The
specific structure of the roller 54 is well-known in the art.
Heat imparted to t]he laminate 53 by the heaters 52 i9
sufficient to enable production of an ade-quate seal between the
films 43 and 49 with the wires disposed therebetween. If desired
a pressure roller 55 may be coordinated with the roller 54 to
insure an adequate seal. The films 43 and 49 with the wires 47
disposed therebetween are then further cooled by roller 56 where-
upon they are fed about a roller 57 and wound upon the spool 58.
The resultant product is shown in cross-section in Figure 5C,
thouyh in actual practice the thickness of the combined plastic
layers may not exceed the thickness of the wires.
The form of the invention shown in Figur~ 6 is sub-
stantially identical to that form illustrated in Figure 5 except
that one of the plastic sheets is coated with a heat sensitive
adhesive prior to lamination with the other layer. Accordingly,
in these two figures, like numerais are utilized to denote like
components. In this embodiment of the invention film 43 is first
fed onto the roller 46 in the manner described in connection with
Figure 5 whereupon the longitudinal wires are fed into overlying
relationship with the film. The film 49 is fed from a spool 50
about rollers 59 and 60 and thence onto the drum 61. An adhesive
contained in the trough 62 is applied to the surface of the film
49 by rollers 63 and 64 whereupon the film then travels about
the roller 61 and is dried by a radiant heater 65 and/or hot air
52
as desired. The coated film then leaves the roller ~1 and is fed
about the roller 50 and onto the roller 46 in overlying relation-
ship with the wires to produce an initial laminate denoted by the
numeral 53 and illustrated in section in Figures 6A and 6B. The
preliminary laminate passes between-heaters 52-52 and thence
about the cooled vacuum roller 54 which by reason of the perfor-
ation of the film 43 produces adherence of the two films one to
the other. Inasmuch as the heat sensitive adhesive is utilized ,
the temperature of the films,in order to effect sealing, would
not need to be as high as in the case of the apparatus shown in
Figure 5 with the result that one of the films, namely, film 49
would be slightly deformed to lie closely about the wires 47 as
shown in Figure 5C. In this figure the adhesive is denoted by
the numeral 49'. If desired, in order to provide a more effective
seal, a pressure roller 55 may be utilized in combination with
the roller 54 in which event the resultant product would take
more nearly the form shown in Figure 5C of the drawings. In
Figures 6A to C the thickness of the f ilms have been enlarged
for illustrative purposes.
In the previous embodiments o~ the invention a laminat~ .
was ~ormed utilizing a plurality of longitudinal wires with a
layer of plastic on either one or both sides of the wires as the
case may be. It is evident however that if desired in the pre-
vious embodiments of the invention one of the films may be pre-
viously for~led with wires extending transversely thereof so that
the resultant product would have both transverse and longitudinal
wires disposed t~rein and thus form in effect a grid enclosed in
a plastic. It is also evident that various sizes of wire and
~15Z~
various thicknesses and types of plastic materials may be em-
ployed depending on the use of the resultant productl
Figures 7 and 8 illustrate two forms of the invention
for producing resultant products having both longitudinal and
transverse wires embedded in plastic sheets. While any number
of procedures may be utilized in forming a plastic sheet with
transverse wires therein one suitable procedure involves the
utili2ation of a product such as shown in Figure lC, lC', 2C, ~,
4B, 5C or 6C and cutting them to lengths equivalent to the width-
of the sheet. Each severed portion is rotated 90~ and then suc-
cessive such portions secured together by heat sealing or other
suitable means to provide an elongated roll of film wherein wires
extend transversely of the film. Such a structure may be
utilized in connection with Figure 7.
The apparatus of Figure 7 includes a drum 69 having
vacuum ports distributed over the surface thereof and means for
the circulation of a suitable fluid therethrough for controlling
the temperature of the drum. This is desirable inasmuch as
heating means are provided about the drum as will be described
in order to raise the temperature of the films for the purpose
of lamination. A first film denoted by the numeral 70 is fed
from a spool 71, about a roller 72 and onto the drum 69. There-
after a plurality of longitudinal wires 73 are fed from a
plurality of spools 15' about rollers 74 and 75 into overlying
relationship with the film 70. The rollers 74 and 75 correspond
essentially to rollers 15 and 16 of Figure 1. A perforating
drum 76 having a plurality of tines extending therefrom per-
forate the film 70 so that the vacuum produced within the drum
29 will caus;e the film to adhere closely to the surface of the
151521
drum. The film 70 together with the wires 73 then passes beneath
the heater 77 which raises the temperature of the film and the
wires to a point close to the melting point of the film. A
second film 78 is fed from a spool 79 and about the roller 80
into overlying relationship with the wires 73 and thence past the
heater 81 that imparts heat to the outer film and raises it to
a temperature required for se,aling it to the first film 70.
One or the other of the films 71 and 78 contains trans- .,
verse wires and the film may be produced in a manner previously
described. The heated structure then passes between the nip of
drum 69 and roller 82 in order to effect the seal between the two
films and the sealed films then pass about the roller 82 and then
about rollers 83 and 8~. Rollers 82 through 84 also function to ¦
cool the laminate so that the resultant laminate 85 is ready to
be rolled upon a spool or carried to subse~uent processing
apparatus. The resultant laminate 85 is shown in Figures 7A and
7B. In this casà the film 70 has a plurality of wires 70' and
the wires 73 are disposed between the film 70 and the film 78.
A cross-sectional view of the structure shown in Figure 7A is
illustrated in Figure 7B. Figure 7C is ~imilar to Figure 7B a~d
shows more precisely the relative thicknesses of the plastic
layers and wires.
The structure shown in Figure 8 differs from the
structure shown in Figure 7 in that an adhesive is utilized in
order to secure the two plastic sheets one to the other. In
this form of the invention a drum 69 substantially identical t~
the drum described in connection with Figure 7 is utilized and
the first film 70 is fed from a spool 71 and about the roller 72
onto the drum 69. A plurality of wires 73 are then fed from a
fl ~15.'~1
plurality of spools 15' and about the rollers 74 and 75 into over
lying relationship with the film 70. The wire 73 and film 70
are then fed beneath the heater 77 to bring the film and the wire
up to a sealing temperature. The film 78 is fed from a spool 79
about a roller 80 and onto a drum 86 having heating means 87
disposed about a portion of the periphery thereof. An adhesive
contained in the trough 88 is fed by means of rollers 89 and 90
to the outer sNrface of the film 78 and the coated film is then
dried by the heater 87 and is ed onto the drum 69 in overlying
relationship with the wires 73. Further heat is imparted to the
laminate on the drum 69 by the heater 81 to complete the seal
between the two films with wires 73 disposed therebetween. As
in the case of Figure 7 one or the other or the films 70 and 78
preferably includes transverse wires so that the resultant
structure has both longitudinal and transverse wires forming in
effect a grid embedded in the plastic laminate. The complete
laminate then passes about rollers 82, 83 and 84 which are pre-
ferably cooled so that the resultant laminate 85' is ready for
further processing or storage-as the case may be. If desired
the roller 82 may be in pressure engagement with the laminate
as it passes between that roller and drum 69 in both Figures 7
and 8 to insure uniform sealing of the layers. The resultant
structure fi5' is shown in Figure 8A and includes the film 70
having wires 70' disposed therein, a layer of adhesive 78' and
a bottom layer of plastic 78. Thë wires 73 are, of course,
disposed between the layers. Figure 8B is a cross-sectional
view of Figure 8A.
Figure 9 illustrates an embodiment of the invention
for producing a reinforced corrugated lamlnate that may be used
~ 152~
for the formation of cartons and the like in the packaging of
articles as well as for structural elements. The resultant
structure essentially comprises a corrugated portion having over-
lying layers on one or both sides thereof. The corrugated portio
is preferably reinforced with transverse wir~s though longitudina;
wires may also be used and the overlying layers may be similarly
reinforced by longitudinal or transverse wires or both as the ,
case may be.
In this embodiment of the invention the first plastic
sheet 91 preferably pre-coated with an adhesive is fed from a
spool 92 about a roller 93 and onto a drum 94. The drum 94 may
be temperature controlled to impart heat to the film 91 to raise
its temperature to the vicinity of the melting point. The film
~ 91 may, of course, include transverse wires as previously de-
j~ scribed in connection with the embodiment of the invention shown
in Figures 7 and 8 or it may be an unreinforced film. There-
after a plurality of longitudinal wires 95 are fed from a plural-
ity of spools 15' and about rollers 96 and 97 (rollers 15 and 16
of Figure 3) onto the drum 94 in overlying relationship with the
film 91 in much the same manner as described in connection with
Figure 3. A second film 98 is fed from a spool 99, about the
roller 100 and onto the drum 94 in overlying relationship with
the wires 95. The film 98 may or may not be provided with longi-
tudinal reinforcing wires as described in connection with the
film 91.
The laminate is then fed downwardly through a heater
101 and about the rollers 102 and 103 to the corrugating rollers
104 and 105. If the film 91 is perforated in the same manner as
described in the embodiment of the apparatus shown in Figur~ 7
;
~ S.2~
and 8 or if the film is pre-perforated, the roller 102 would then
be provided with a multi~licity of vacuum ports in the surface.
thereof with appropriate vacuum means connected to the ports in
.a manner well-known in the art, and sealing would then be effect-
ed on the vacuum roller. On the other hand if the film 91 is not
perforated, rollers 102 and 103 could be positioned in close prox- .
imity one to the other to provide sufficient pressure to effect
a satisfactory seal. In either case, however, the roller 103 is .
preferably cooled to lower the temperature of the complete lami-
nate prior to engaging the corrugating rollers 104 and 105.
The resultant laminate denoted by the numeral 106, the
passes downwardly through a heater 107 to again raise at least
the surface layers of the corrugate to a sealing temperature.
A third film 108 preferably pre-coated with an adhesive which
I may or may not contain reinforcing wires is fed from a spool 109
¦l and about rollers 110 and 111, the latter being heated in order
to bring the adhesive on the surface of the film 108 to a sealing
temperature. The heated film 108 is then fed about a roller 112,
which may also be heated and then into surface contact with the
corrugated structure 106. A fourth and preferably pre-coated
film 113 sLmilar to the film 108, is fed from a spool 114 and
about the rollers 115, 116 and 117 into overlying relationship
with the other side of the corrugated structure 106. The roller
116 is heated in the same manner as described in connection with
the roller 111 and if desired the roller 117 may also be heated
in order to maintain the temperature of the film 113 at the
sealing temperature as in the case of the film 108.
The corrugated structure 106 together with the over-
lying layers 108 and 113 is fed between a pair of cooling belts
. 118 and 119 with the belt 118 being carried by cooled rollers
~:'L515Zl
120 and 121 and the belt 119 being carried by cooled rollers 122
and 123. Belts 118 and 119 are in sufficiently close proximity
one to the other to apply pressure to the laminate to insure
sealing of the overlying layers to the corrugated structure 106
without substantially deforming it. The resultant structure is
denoted by the numeral 124 and is ready for further processing
or use.
A cross-sectional view of the corrugated structure 106
is illustrated in Figure 9A, the plastic layers havi~g been en-
larged in thickness for illustrative purpose. It will be ob-
served that the film 91 includes transverse wires 91', longitud-
inal wires 95 and the plastic layer 98. The final structure 124
as shown in Figure 9B includes the corrugated substructure 106
having longitudinal and transverse wires and a pair of overlying
layers of plastic 108 and 113. A modified form of the invention
is shown in cross-section in Figure 9C ~nd denoted by the numeral
124'. In this form of the invention the structure 106 has over-
lying layers 108 and 113 as in the case of Figure 9B, but also
inciudes transverse reinforcing wires 108' and 113'. It is, of
course, evident that the overlying layers 108 and 113 may also
include both longitudinal and transverse reinforcing wires, as
shown for instance in Figure 13E which will be described.
The form of the invention shown in Figure 10 is simila3
to that illustrated in Figure 9 and like numerals are utilized
to denote like components. The formation o~ the corrugated
laminated reinforced structure 106 is substantially identical to
that illustrated and described in connection with Figure 9. The
overlying layers however are coated with an adhesive just prior
to the application to the corrugated structure. More specificall~ ,
~51~
the film 125 is fed from the spool 126 about rollers 127 and 128
thence upwardly through an oven 129. A trough 130 carries an
adhesive which is applied to the film 125 by a roller 131. The
adhesive is dried in the oven 129 and then fed about the rollers
132 and 133 into contact with one side of the corrugated struc-
ture 106. The apparatus for applying the second film 134 to the
othèr side of the corrugated structure 106 is identical to that
described above and like primed- numerals are utilized to denote ~,
like components. The corrugated structure 106 together with the -
two films 125 and 134 are fed downwardly between cooling rolls
135, 135' and 136, 136' to cool the structure and insure good
adhesion of the outer layers. The resultant ~tructure is denoted Y
the numeral 137 and is illustrated in cross-section in.Figure
lOA. In this figure the corrugated structure 106 is identical
to the illustra~ed in Figure 9A and it includes the outer layers
125 and 134 secured to the corrugated structure by adhesive layers
125' and 134'~ The outer layers 125 and 124.may include rein-
forci~g wires as illustrated in lOB wherein the reinforcing wires
are denoted by the numeral 138 in the layer 125 and the numeral
139 in the layer 134. Longitudinal reinforcing wires are also
preferably included.in the outer layers as shown in Figure 13E
to be described.
The preceding embodiments of the invention such as the
embodiments shown in Figures 1 and 4 through 10 may be made utiliz
ing a wire grid in plaae of the longitudinal wires in which event
the provi3ion of a plastic layer having transverse wires embedded
therein woul,d not be necessary. Thus, in Figure 9 for example,
~ S~l
the films 91 and 98 would not need transverse wires since a wire
grid could be fed between the films in place of merely the longi-
tudinal wires 95. An Lmproved method and apparatus for produc-
ing such a grid is illustrated in Figure 11.
In Figure 11 a transversely corrugated belt generally
denoted by the numeral 140 is carried by a pair of drums of which
only one is illustrated and denoted by the numerals 141. Suitable ~,
means are provided for cutting wires into predetermined lengths
and feeding them individually into the troughs of the belt 140.
The wires denoted by the numerlas 142 are illustrated on the top
side of the belt and move in direction toward the drum 141.
A plurality of narrow belts 143 carried by sets of rollers 14~,
145 and 146 hold the wires 142 in position on the corrugated belt
140 as it travels downwardly about the left side of the drum 141
is shown in Figure 11. As each wire reaches the bottom-most
portion it is discharged onto a~drum having a plurality of axially
aligned hooks 148 disposed about the periphery thereof. As each
of the wires 142 is discharged onto the drum 147 it is engaged
by one set of hooks and is therefore retained in position as the
drum 147 rotates. A set of longitudinally disposed wires,
denoted by the numerat 149, are fed from a plurality of spools
15' in much thè same manner described in connection with Figure
3. Thesa wires are fed about the rollers 150 and 151, correspond-
ing to the rollers 15 and 16 of Figure 3, and pass between the .
nip of that roller and a second roller 152. The roller 152
is preferably grooved to insure the maintenance of proper spacing
between each of the plurality of wires 149. ~ires 149 then pass
beneath the heating means 153 and about the roller 154 which has
f~
~```
~ sz~
:
a resilient layer 155 on the surface thereof and preferably
includes a plurality of groovles formed therein in order to clear
the axial arrays of hooks 148 carried by the raller 147. The
wires 149 ride about the surface of the outer layer 155 on the
roller 154 and are urged into tight engagement with each of the
transverse wires 142 to form a grid. In the preferred embodiment
however the wires 149 are coated with a heat sensitive adhesive .
o- plastic which will insure a firm union between the two sets
of wires. The joined wires, which now form a grid, are carried
about the roller 147 and are guided by the roller 156 onto the
spool 156. It is preferable, ofc~rse, that the drum 147 be
cooled in order to rapidly lower the temperature of wires after
they have been joined. A cross-sectional view of the resultant
grid is illustrated in Figure llA wherein the longitudinal
wires 149 are shown gripping the transverse wires 142. If bo~h
sets of the wires have been pre-coated with a plastic or suitable
adhesive of the heat sensitive type it will facilitate formation
of a structure wherein the wire grid is corrugated and then
overlying layers are applied as will now be dscribed in connection
with Figure 12.
In Figure 12 a wire grid, denoted by the numeral 1~8,
is fed from a spool 159 and about a roller 160 to corrugated
rollers 161 and 162. The corrugated grid, now denoted by the
numeral 158', is fed through a heater 163 and thence downwardly
between a pair of b~lts 164 and 165. The belt 164 is carried
by a pair of rollers 166 and i67 while the belt 165 is carried
by a pair of rollers 168 and 169. The rollers 166 through 169
are preferably co~led in order to maintain the balts at a tempera-
., ('~' ?
~ S2~
ture well below the melting point or embossing temperature of thefilms to be applied to the surface of the corrugated structure.
A first film of plastic 170 is fed from a spool 171 about roller
172 and onto the outside of the belt 164 as it passes about the
roller 166. A second ~ilm 173 is fed from a spool 174 about
the roller 175 and onto the belt 165 as it passes about the
top side of roller 168. Since the wires have been heated to a 4
relatively high temperature in the heater 163 they will impart.
sufficient heat to the films as they are pressed into engàgement
with the wires by the rollers 166 and 168. At the same time the
rollers acting through the belts 164 and 165 maintain the films
170 and 173 in firm engagement with the corrugated grid while
the entire structure is cooled. The resultant structure denoted
by the numeral 176 is shown in Figure 12A. The corrugated grid
is denoted by the numeral 158' and it will be observed that the
outer portions thereof are embedded.in the outer layers of
plastic 170 and 173. In most cases when utilizing a wire grid,
it is preferable to use coated wires in order to protect the
metal from corrosion.
A still further modification of the invention is illu-
strated in Figure 13 and illustrates one method and apparatus for
continuously producing a corrugated structure wherein a rein-
forced corrugated layer is first produced and then the overlying
layers are successively applied. In this figure a plurality of
longitudinal wires 180 are fed from a plurality of spools 15' and
about rollers 181 and 182 (which correspond to rollers 15 and 16
of Figure 3) onto a cooling drum 183 which may be cooled by the
circulation of water or other:liquid coolant in the manner well-
known in the art. Immediately after the application of the wires
-26-
1 ~ 2~
a plastic layer is applied to drum 183 by an extruder 184.
Thereafter a plastic sheet or film 185 is fed from a spool 186
and about a roller 187 into overlying relationship with the ex-
truded layer 188. Inasmuch as the layer 188 is at a relatively
high temperature it will encase the wires 180 and since it is at
least at the normal sealing temperature it will adhere to the
film 185 which is applied immediately after extrusion. The layer
185 preferably comprises a film previously processed to combine .
it with transversely positioned wires in the manner previously
described. Figure 13A shows a cross-sectionaliview of the wires
180 immediately after the layer 188 is extruded onto the drum
183 in overlying relationship with the wires. Figure 13B is a
cross-sectional view of the structure after the film 185 is applie~ L
to the extruded layer 188. In this figure it will be observed
that the layer 185 includes transverse wires 185'. The structure
is shown in Figure 13B which is formed on the drum 183 is then
removed by a roller 189 whereupon it passes through heating means
190 and thence to a pair of corrugating rollers 191 and 192.
The corrugated structure denoted by the numeral 193 passes about
rollers 194, 195 and 196 and is then fed onto a second cooling
drum 197 by means of the roller 198. Preceding the application
of the structure 193 to the drum 197, a second extruder 199 feeds
a plastic layer 200 onto the drum 197. While the drum 197 is
cooled in the s~me manner as drum 183, nevertheless the plastic
layer 200 is at a relatively high temperature and therefore upon
the application of the corrugated structure 193 it will firmly
adhere to the layer 200. The resultant structure is shown in
cross-section of Figure 13C and is removed from the drum 197 by
a roller 201 ana is then fed abo~t rollers 202 and 203 onto the
drum 204. Prior to the application of the corrugated structure,
515Zl
with a layer of plastic applied to one side thereo~, to the drum
204 a third extruder 205 applies a plastic layer 206 to the ~rum.
This plastic layer forms a second overlying layer for the corru-
gated structure. since the extruded layer 206 is at a high tem-
perature when the corrugated structure is applied it will firmly
adhere to the structure whereupon the layer 206 is cooled by the
drum 204 in the same manner as the layers 188 and 200 were cooled
by the drums 183 and 197. The resultant structure is then re-
moved-by roller 207 and the final material is denoted by the
numeral 208.
A cross-sectional view of the resultant structure
208 is shown in Figure 13D which shows the relative positions of
the several layers including the reinforcing wires in the corru-
gated structure. From the foregoing description it is quite
evident that reinforced layers such as shown in Figure 7B and
7C, and 8B may be utilized as the outer layers in the formation
of the corrugated structure by apparatus shown in Figure 13 in
place of the extruders 199 and 205. In such a case the reinforced
layers would be preheated b~efore being fed to the drums 197 and
204 in order to provide adequate heat to effect a seal with the
corrugated structure 193`. The utilization of outer layers 209
and 210 such as shown in Figures 7B and 7C and 8B would produce
a resultant structure as illustrated in Figure 13E. However, in
the latter case it is generally not necessary to use longitudinal
wires in the corrugated structure as the outer layers provide
adequate structural strength. For purposes of illustration, the
plastic layers and wires have been exaggerated in thicknesg in
Figures 13A to 13E. Figure 13E' illustrates the product of
Figure 13E with the relative thicknesses of the plastic layers
and wires more precisely displayed.
. .
-28-
. '
. ~`
~ 15Zl
It is evident that the various products thus Ear dis-
cussed and manufactured in accordance with the invention may be
utilized either alone or in combination with the other types of
packaging materials in order to meet a wide variety of needs in
the packaging industry. For instance, the structure denoted by
numeral 85 in Figure 7C may be combined, as illustrated in Figure
14, with a cellular material generally denoted by the number 211
to provide a substantially rigid wàll covered on at least one .
side by the cushioning material. The cushioning material may take
any suitable form and may be a material such as illustrated and
described in U.S. patent No. 3, 142,599. Figure 15 illustrates
a further modification of the invention wherein the ~ayer 85 is
combined with a plastic foam ~12 formed of polyurethane or other
suitable material. It is evident that while the reinforced
plastic layers 85 have been illustrated in Figures 14 and 15 simi-
lar combinations may be made with the reinforced layers shown in
other of the figures previously described. Figures 16 and 17 show
still additional products which may be manufactured in accordance
with the invention. In Figure 16 the structure as shown in Figure
13E is combined with the cellular material 211 wh le in Figure 17
the same structure is combined with a plastic foam 212. It is,
of course, evident that the structure of Figure 13D may be utiliz-
ed in place of the structure of Figure 13E and even a structure
such as shown in Figure 13C may be utilized either in the manner
illustrated or may be reinforced with longitudinal or transverse
wires.
In all of the embodiments of the invention illustrated
and described it is evident that various types of materials may
be utilized in their fabrication. For instance, the reinforcing
elements may be formed of steel having the desired carbon content
and various steel alloys as well as aluminum, copper and other
similar metals may be utilized whic~ afford structural strength
and rigidity. Lightweight metals such as magnesium or even tung-
sten may be used where w~ight is a significant factor. In con-
nection with the plastic material polyethylene of various densi-
ties, polypropylenes and their copolymers, polystyrenes and poly-
vinyl chloride may be employed, various polyesters and polyamides
can also be used. Thermosetting resins may also be employed for
various applications such as modified and flexible phenolic resins,
also phenolformaldehydes, urea-formaldehydes, furfural-formalde-
hydes as well as melamine-formaldehydes. In order to provide
resistance to moisture vapor and other gases the plastic films
i,utilized may be pre-coated with a film of polyvinylidene chloride
~or other similar relatively gas impervious plastics. As pre-
viously mentioned the various products produced in accordance
¦with the invention have been illustrated in most cases ~ith the
thicknesses of the plastic and adhesive layers being exaggerated
in thickness for clarity. However, in each instance the plastic
layers are usually about one-half the thickness of the reinforcing
wires. It is also understood that the number of wires per inch,
the thickness of the wires and the thickness and type of ~he
plastic layers can all be modified to achieve the desired struc-
tural strength. Similarly, the arrangement of the reinforcing
wires can also be selected to achieve the desired ends. For
instancP, when using both longitudinal and tr~ansverse wires in
the layers overlying the corrugated structure it m~y not be nec-
essary to usa the longitudi~al wires in the central corrugated
structure. The term 'Iwires" as used in this application is in-
tended to include wires of various cross sectional configurations
such as round, oval, flat, square and the like.
r ~L151 S2i
While only certain embodiments of the invention have
been illustrated,and described, it is understood that modifica-
tions, alterations and changes may be made without departing
from the scope and spirit of the invention as defined in the
appended claims.
WHAT IS CLAIMED IS:
- 3~
. ,,,'`,,
. : ,
