CA1113047A

CA1113047A - Merchandising package for containers

Info

Publication number: CA1113047A
Application number: CA278,933A
Authority: CA
Inventors: James E. Heider
Original assignee: Owens Illinois Inc
Current assignee: OI Glass Inc
Priority date: 1976-06-09
Filing date: 1977-05-20
Publication date: 1981-11-24
Also published as: AU2587677A; FR2354258A1; AU510323B2; GB1564772A; DE2723762A1; FR2354258B1; DE2723762C2; MX146199A; JPS52152395A; JPS5754384B2

Abstract

MERCHANDISING PACKAGE FOR CONTAINERS
Abstract of the Disclosure Disclosed is a multiple container merchandising package comprising a group of similarly shaped containers held together in side-by-side fashion by a plastic overwrap comprising an opaque, uniaxially oriented, laminated, composite sleeve of thermoplastic foam and a thermoplastic film.

Description

10 ' _ This invention relates to a package for two or more _ containers such as cans, bottles, jars, cannisters, made of glass, metal, or rigid plastic or paper~ In a more specific aspect the present invention relates to an improved ` .
I merchandising package for a plurality of such containers ! wherein performance,economy, and~appearance of the package are primary considerations. -Today's marketing of bottled and canned beveragesand other products calls for suitably packaged clusters of such containers, perhaps the most familiar of which is the so-called "six-pack". The package must safely and firmly ~ holdthe.containers, it must lend itself both to ready 1.
l independent portability for consumer use and to bulk ~ stacking for warehousing and shipment, and it must lend .l itself to reliable and economical massproduction. The advent 1 of shrinkable plastic overwrapq has resulted in drastic 1~ changes from the cardboard packages of the past, and . , '. .
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~ I U~ S Patents 3,532,214; 3,198,327; 3,552,559; 3,834,525;
Re 28,535; 3,650,39~; 3,650,395; 3,817,373; 3,416,288;
3,7~7,749; 3,331,503; 3,302,784; 3,477,56~; 3,756,397;
1 and 3,217,874 are representative of packages with plastic 1, overwrap. Most of these patents are concerned with the use !l of various transparent, nonfoam shrink wrap packages and to ¦ the use of various handles, "fingerholes" and adjunct supporting structures.
I Multicontainer packages using this transparent thermo-I plastic films are suitable for many applications althoughthere are marked disadvantayes for the packaging of glass ' containers containing products such as beer which are sensitive to light. Furthermore such thermoplastic films do I not provide a great deal of cushioning protection in l~andling.
, It is also quite difficult to decorate such transparent thermoplastic films and such packages often require the attachment of supplemental labels for the purpose of identification ,; and decora~ion.
I It is noted that U. S. Patent 3,400,810 discloses ~ the use of foam polystyrene for shrink wrapping of multicontaine~
packages. However, the foam polystyrene disclosed in this , patent is biaxially oriented and will shrink in both directions. Such a shrunken overwrap will have the same i~ strength properties in both directions making removal of the l~¦ containers somewhat difficult. Furthermore it will be difficult to form a seal on the end flaps of package cluster due to axial 3~'7 1, ,~ ~

~ as well as circumferential shrinkage of the overwrap. It is noted, ¦. that the pac~ages illustrated in this patent engage only a small fraction of the end containers in the cluster. Moreover 1. it is necessary for the patentee to use a very thick film ¦' in the neighborhood of 40 mils to achieve the required strength.
¦~ Thus it is the primary object of the present invention ~¦ to provide an improved multicontainer merchandising package l~ which is strong but yet is easily opened, opaque to light I
I and is capable of being preprinted with information or decoration prior to application and requires no external structure for handling purposes.
In attaining the objects of this invention, one feature resides in a multipie container merchandising package com-prising a group of similarly shaped containers held together . in side-by-side fashion by a plalstic overwrap comprises an opa~ue~ uniaxially oriented, laminated composite sleeve which is uniaxially oriented in the circumferential directi.on and comprises a closed cellular (i.e. foam) ~ thermoplastic polyolefin layer laminated to a noncellular thermoplastic polyolefin film, said sleeve circumscribing the containers and snugly engaging the tops of the containers 1 in shrink fit relation.
¦. An essential feature of the present invention is in the 1 composition of the heat shrin~able polymeric sleeve, which is of a composite ~tructure having a layer of a cl e_ cellular ,, ~ . ~ I
ll i (e.g. foam) olefin polymer adhered to a layer of a noncellulax olefin polymer film wherein the cellular layer is in on the inside of the sleeve and in engagement with at least the tops Il of containers and the film is on the outside of the sleeve 5 11 and has a smooth, glossy decorated surface.
¦~ other objects, features, and advantages of the present ¦i invention will be apparent from the description and draw-¦, ing~ which follow wherein ~ Fig. 1 is a perspective illustration of a "six-pack"
I of glass bottles packaged in accordance with the present invention;
' Fig. 2 is a bottom view of the package of Fig. l;
¦~ Fig. 3 is a perspective illustration of a six-pack ~l of cans packaged in accordance with the present invention;
' Fig. ~ is a perspective illustration of a 12-pack of glass beer bottles packaged in accordance with the present invention; and ,~ Fig. 5 is a cross sectional illustration of the composite ' laminate used as the overwrap in Figs. 1 through a, ¦ Referring now to Figs. 1 and 2 reference numeral 10 generally refers to the cluster package of six conventional upstanding one-way beer bottles 15 having similar cylindrical bodies. The containers are arranged in two adjacent rows ~ each having three side-by-side containers.
~ As can be seen in Fig. 1 the tops 12 of the bottles 15 ,~ are snugly engaged by sleeve 11 and the bottles are contained i I . , I`
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and confined in all directions so as to prevent relative movement of the individual containers within the package. Fig.

2 illustrates how the bottoms 16 of bottles 15 are also snugly , engaged by the sleeve~ The heat shrunk opaque, overwrap ' sleeve of invention is indicated by reference numeral 11 and I is applied so that the direc-tion of uniaxial orientation is ¦ in the circumferential or radial direction oE the sleeve.
Sleeve 1~ is shown with decoration generally indicated by the , letter "X". Such decoration is applied prior to wrapping the ~ sleeve around the package.
The sealing seam of the sleeve is designated by lla and is shown as being positioned on the lower sicle of the package.
The seam is formed by the use of adhesives or by th~rmall~
! fusing edges of the sleeve together. The seam is positioned 15 ~ on the side of the package as a matter of convenience and could also be located at the bott:om or top oE the package.
The open end of the sleeve 11 defi~Qs an aperture 13 which is formed as the overlaying ends of the sleeve shrink and use , together. The other end of the package (not shown) has similar configuration and appearance. In forming aperture 13 there I is some shrinkage in the sleeve (e.g. less than 10~) in the f axial direction and this assists in the formation of the tight package. IE there were too much shrinkage in the axial direction, ~ the aperture would be too large, and the sleeve would not 25 ~ effectively retain the bottles~ In this regard it is important that the sleeve extend to cover the point of farthest extension , i of the container from the package so as to prevent container-to- !
container impact when several of such packages are transferred l~ ~
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in end-to-end fashion on a conveyor. This point is approximately~
designated by the lead line for reference numeral 13 in 1-Fig. 2, ~ The upper rim 13a of aperture 13 is quite functional and 5 ,' serves as a convenient gripping surface for transporting the package. Due to the nature of the uniaxially orientation, rim 13a is quite strong against the stress of lifting at this point and readily supports the weight of containers and their I! contents.
10 i To open the package all one need do is punch a hole with the inger or other instrument through the top of the package at point between tops 12 where the sleeve is tightly drawn.
Such a point is generally illustrated by reference numeral 14.
Once the sleeve ispunctured in these areas it will readily tear in the circumferential direction and the bottles can ~e easily removed individually or in pairs. The sleeve is quite resistant to tearing in the axial direction so the package remains intact with respect to the remaining containers in ~ the cluster.
20 , ~ig. 3 generally illustrates a package 20 similar to ` that shown in Figs. 1 and 2, except that the containers are in the form of cylindrical metal cans 21 rather than bottles.
The sleeve 23 is otherwise as explained with respect to Figs.
' 1 and 2 and is sealed together at seam 22, Fig. 3 also illustrates how finger opening can be used 1 with the package of invention if desired although the finger hole~
¦~ is not used in the presently preferred embodiment. Reference numeral 25 represents a ~inger slit which is cut in the 1: 1 1 .

~13~47 circumferen-tial direction on sleeve 23. The slit ~erminates in semicircular cuts 25a which serve to retard tearing in the circumferential direction upon carrying. It will be ~ understood that some care must be exercised when carrying the 5 ¦I package by finger slits. Reference numeral 24 represents ¦` another type of circumferential finger slit which is formed ¦~ by pushing a hot loop of wire through the sleeve. Slit 24 ¦, is sealed by beaded edges 24a which are formed by contact I with the hot wire. In practice it is likely that all the 10 ¦ slits on one package will be of the same type.
~I Fig. 4 generally illustxates a 12-pack 30 of one-way beer ¦ bottles arranged in three rows of four bottles each confined ¦ by sleeve 30 in tray 32. The package configuration is generally ¦` the same for that shown in Figs. 1 and 2 except that the 15 1 bottoms of containers 31 set in tray 32 whlch is shown as being made of corrugated fiber board. The outline of tray 32 is generally seen under the sleeve 30 and comprises a flat bottom ,; panel provided with short upstanding side walls on all sides.
l~ Tray 32 i5 used for added package rigidity when more than two 20 , rows of containers are packaged to prevent relative displacement ~ of the packaged containers with respect to each other. Due to ,~ the use of tray 32 only the tops 34 of the bottles are snugly engaged by sleeve 30 and the bottoms of the containers are , held securely against the tray~
25 ¦ Sleeve 30 is applied so that the direction of uniaxially orientation is in the circumferential or radial direction of the '"` Il` l 1: . I

sleeve and two sealing seams 33 are shown as being positioned on the lower part of the package overlaying the side wall portion ! of the tray 32. In this embodiment the sleeve is applied j, and sealed as two separate sheets, That part of the sleeve ¦ covering the bottom of the tray need not ba foamed and can be I any compatible thermoplastic film. In some embodi~ents it may ¦ be preferred to use a less expensive non-decorated thermoplastic ¦ film for covering the bottom of the tray. Furthermore txans-I parent films can be used to cover the tray bottoms when it is I desired or required to read specifications or other information printed on the tray bottom. As a further embodiment the sleeve can be formed by sealing the composite to the tray at the point I where sealing seama~ 33 are located. In this embodiment the ¦ hottom of the tray serves as a part of the sleeve. It is thus 15 ll apparent that the entire sleeve need not be made of the composite I so long as the composite circumscribes the containers and snugly i engages the tops of the containers in shrink fit rela~ion. In this regard the term sleeve as used herein refers to this jl relationship.
j As has been previously described with respect to Fig. 1 the ¦I rim 35 oE the aper-ture 36 in the end of sleeve 30 provides a ! convenient handle for carrying. Most 12-packs would probably ¦¦ be too heavy to permit the use of finger holes. The end of the ¦I package which is not shown is identical in configurati~n to the 1'i end shown.
Fig. 5 shows a cross sectional view of the sleeve of Figs. 1 ¦
j through 4 with 40 representing the foam or cellular layer and ¦41 representing the noncellular film laminated thereto. The total I thickness of the lamina~e composite is usually in the range of a-~¦ bout 3 mils to about 20 mils and preferably in the range of about 5 to abou-t lS mils for efficiency and economy. The ce~lular lay r 40 is usually about 2 to about 5 times and preferably about 3 timls the thickness of noncellular film 41 and noncellular layer ; 41 is usually positioned on the outside of the sleeve.
5 ` The polymeric materials respectively and independen-tly contemplated for cellular layer 40 and noncellular layer 41 are olefin polymers; that is, each of these polymeric layers I will have as the predominant polymeric moiety a polymar of an I ¦ olefin, preferably an olefin having 2-4 carbons, or mixtures ¦ thereof, e.g. the predominant moiety will be a polymer of ethene, propene, butene, like butene-l, or mixtures thereof, more commonly referred to as a polymer of ethylene, propylene or butylene. This includes homopolymers, copolymers of these Il olefins with other copolymerizable monoethylenically unsaturated 15 !I monomers, wherein the olefin in the copolymerization is such li that the moiety thereo~ in the final copolymer, that is the ~I ethylene, propylene or butylene moiety, is at least about 1 60% by weight, and polymeric blends, or admixtures, wherein ~ the resulting polymeric blend is at least about 60~o by weight of a polymerized olefin moiety, e.g. at least about 60% .
of an ethylene moiety in the blend. The minor amounts, i.e. less than about 40% of the other moiety of material employed, are such as to supplement and compliment the basic ' properties of the olefin polymer and this applies whether other moieties are introduced by way of a polymer blend, i or admixture, or by way of a copolymerized monomer. These other moieties, whether supplied by blending another polymer , with a homopolymerized olefin, e.g. homopolymerized ethene, _9_ I
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v~ 7 -(ethylene homopolymer), or by copolymerization therewith, should not be such as to significantly interfere with the foamable, heat sealable, heat shrinkable, extrudable characteristics of the base olefin polymer and should be ~ compatibLe~ i.e. miscible with it.
Exemplary alefin homopolymers are ethylene, propylene and butylene homopolymers, with the former being especially preferred, and blends of these homopolymers. The terms I polyethylene, polypropylene and polybutylene are used herein to include those materials recognized and sold commercially under those names, even though those materials~ strictly and technically, may be viewed by some to be a blend, or i copolymer, since the materials may include small amounts, , typically less than about 55~, e.g. 0.5-3~ by weight, of another polymeri~ moiety~ For examp:Le, ~olyethylene is sold and recognized by that name when in fact it may be produced by copolymerization with 1-2 percent by weight of hexene, or butadiene, or may, by analysis, show several percent, e.g. 3-5~ of vinyl acetate moiety, for practical purposes ` 20 ~ however these materials consist o~ polyethylene. In this regard the composition of the sleeve used in the present `i~ invention is the same composition as the laminate described in commonly assigned United States Patent 4,038,446 -I entitled "Container with Improved ~Ieat Shrunk l Cellular Sleeve".
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lll l The foregoing generally describes the composition of the polymeric portion of the cellular layer 40 and noncellular , film 41, it being understood that the layers need not be of the ¦I same polymeric composition. It will, of course, be apparent 5 ¦I that suitable adjuvants can be present in these layers if desired. Thus, for example in addition to the polymeric material, the respective layers can include pigments, stabilizers and the like. Generally, excellent results will be obtained I by selecting a polymeric composition for cellular layer 40 1~ ~hich has a melt index or melt flow of less than 5, for exam.ple I between about 0.1 to 5 and most desirably about .2 to 1 and ¦ the polymeric material selected ~or the noncellular layer 41 will have a melt index or melt flow of less than about 10.
1 The preferred material for both the cellular layer and the non-15 1 cellul.ar layer is polyethylene, which includes low density, polyethylene, for example polyethylene having a density of . , less than 0.925 grams/cc, generally in the range of about ! 0.910 to about 0.925, high density polyethylene, for example !~ that havin~ a density greater than about 0.941, typically 20 ~. about 0.941 to about 0.965, madium density polyethylene, and ~! blends thereof. As regards the cellular layer, the density ; specified is prior to foaming. The foamed density of cellular Il layer is about 25-30 #/ft.3 and the density of the composite I. laminate is about 35-40 #/ft.
25 i1 As previously indicated the present invention i5 directed.
to an improvement in th here~nbefore-de~cri~ed pac~a~

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$~47 wherein, in producing these packages, a heat shrinkable uniaxially oriented, laminated sheet is first prepared which is appropriately cut and slit and formed into rectilinear ¦I sheets which are then formed into a heat shrinkable sleeve 5 ¦¦ which applied to the cluster of containers to produce ¦l, the ultimate packa~e. While a sheet of stock material of the ~¦ composite structure for use herein can be formed by various techniques it is generally preferred to employ extrusion ¦I technology. This extrusion technology may take either of ¦I two conventional forms, one of which is extrusion coating and the other of which is the use oE co-extrusion technology~
The latter technique, however~ is particularly highly preferred I because of the apparent ability to form lower density ¦ composite structures. In -the co-extrusion technique, while 15 I~ a slit die may be employed, the preferred practice is to employ ¦ an extrusion die which is possessed of an annular, circular ¦l opening and the composite structure is initially formed as I' a tubular shape by what is referred to in the ar-t as a "blown I bubble" technique. These types of co-extrusion dies are 1~ widely available commercially and an exemplary die is set forth , in SPE Journal, November 1969, Vol. 25, page 20, entitled, ¦~ "Co-Extrusion of Blown Film Laminates" and form no part of the present invention as such.
1~ In this known co-extrusion technique the circular openiny l is fed from two independent extruders and, in this particular ~ instance, the e~trud-r supplying the ~oamabl~ material, il I

gL7 intended to form cellular layer ~0, preferably will feed j the die so that this material forms the internal portion . of the tubular e~trusion; the extruder feeding the material 1 intended to form non-cellular layer 41 will preferably be fed to the die so as to form the external portion of the tubular shape. The tubular member issuing from the extruder is blown into a bubble by conventional "bubble" forming techniques, including air cooling of the external surface thereof, and is then drawn through the nip of two juxtaposed ~ rollers wherein the tubular member is compressed to form a flattened tube.
I Suitable convention foaming or blowing agents are employed ¦ to produce foaming and the cellular structure results, ll just as the extrudate leaves the die~ This flattened ~ tube is then contacted with cutt~ing knives which slit the flattened tubular member along its edges (machine direction) , so as to form a sheet or film of substantially uniform - , width; this sheet or film, which is at this point actually ~ a sheet of two superimposed composite structures, for use j~ herein, is separated into two independent sheets and wound . onto independent windin~ wheels, which provides the stock of the .' heat shrinkable composite structure for use herein. Inasmuch l! as the sheet of the composite structure must possess heat !~ shrinkable characteristics the appropriate heat shrinking ,. in the machine direction of extrusion, whlch preferably ! is a major amount and is greater than the cross. direction ~ -13-p 1'7 .1 .

heat shrinkage, is primarily provided by the impetus of the I rate of drawing of the flattened tube through the nip of the j rolls, and using cooling air on the exterior of the bubble, l~ and the cross direction shrinkage, which is less than the machine I direction shrinkage, is primarily provided by the internal ¦ air employed in forming the bubble and ex-ternal cooling air. This of course is known for forming heat shrinkable films.
I The term "heat shrinkable" as used herein refers to ¦ the property of the laminated composite whereby it contracts ¦ in length and/or width upon exposure to suEficient heat.
¦ Shrinking is generally attributable to a reorientation of ¦ molecules which were previously oriented by stretching the i sheet either uniaxially longitudinally (machine direction) or horizontally (transverse direction) or biaxially (both directions). In the practice of the present invention the lamina ed composite sleeve is said to be uniaxially oriented in the cir-cumferential direction. This means that the sleeve is capable of ~ shrinkage in circumferential direction of at least about 2.5 20 1 times and preferably at least about 5 times the shrinkage in the !l axial direction. The sleeves of invention are capable of shrin~in ~at ¦~ least 50~ and pref~rably at least 60~ in the circu~Ecrential ¦
ll direction and less tha~ 20~ and preferably less than 10~ in ¦
¦~ the axial direction. In a particularly preferred embodiment the ¦
25 ¦¦ sleeve is capable of ~hrinkage about 70~ in the circumferential dl-¦~ rection at about 6-8~ in the axial direction. This shrinka~e value is -l4-1, 1``

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!. H-14212 theoretical ~alue rather than value which is experienced in forming a package. The theoretical. values are determined I' by placing a sample of the composite ir~ a hot bath of heat ¦', transfer liquid at 350F for 10 seconds and determining the 5 ¦I resulting shrinkage~ In actual practice the shrinkage is usually much less than theoretical due to the amount of the ¦ composite that is used to wrap the containers. For example a sheet of composite foam polyethylene and film polyethylene with a foam thickness of about 4.5 mils and a film thickness 10 ¦ of about 1.5 mils, which is 21.5 inches long and about 11.5 inche 3 wide forms the sleeve around a si~-pack of one-way beer bottles when heated at 400F for 20 seconds.. In such a package there is an actual shrinkage of about 50~ in forming . the aperture at the end of the pack, about 15~ between bottles lS 1,' and on:ly about 2~ over the bottle tops.
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1~.13~4~7 The term "heat shrunk" describ-es the condition of a Il heat shrinkable material after application thereto of 3I heat sufficient to cause relaxation and shrinkage (e g.
heating in an oven at 450F for about 5 seconds). This heat ~3 treatment heats the sleeve to near the melting point of the ¦ composite.
¦ The sleeve can be applied by conventional method wherein a plurality of containers are carried along a predetermined 1 path which can be a pair of moving conveyors or other 10 '! transport means to an arranging zone such as an indexer wherethe containers are arranged in the desired juxtaposed I relation. Typically this relation is three rows of ¦ containers two abreast. The arranged containers are moved I along a path away from the arranging station to a wrapping station where heat shrinkable composite laminate from a supply roll is placed around the arranged containers. The Il wrap is parallel to the longitudinal axis of the arranged ¦I container cluster or provided the ends of the outermost ~I containers are within the volume defined by the sleeve 20 l after shrinkage.
, The wrapped containers are then passed through a heating zone such as a shrink tunnel where heat sufficient to ~j shrink the film is applied. The arranged containers held Il endwise and sidewise by the heat shrunk sleeve are then 25 ,, passed to a distribution area.
Elor convenience in disclosure, all paten-t documents and publications mentioned herein are inco orated by reference ' . '

Claims

HAVING THUS DESCRIBED THE INVENTION, WHAT IS CLAIMED IS:

1. In a multiple container merchandising package comprising a group of similarly shaped containers held together in side-by-side fashion by a plastic overwrap, the improvement wherein said overwrap is an opaque, uniaxially oriented, laminated, composite sleeve, said sleeve being un-iaxially oriented in the circumferential direction and comprising a closed cellular thermoplastic polyolefin layer laminated to a noncellular thermoplastic polyolefin film, said sleeve circumscribing said containers, and snugly engaging the tops of said containers in shrink-fit relation.

2. The improvement of claim 1 wherein said polyolefin layer is polyethylene.

3. The improvement of claim 1 wherein said polyolefin film is polyethylene.

4. The improvement of claim 1 wherein sleeve has a thickness of in the range of about 3 mils to about 20 mils.

5. The improvement of claim 4 wherein said sleeve has a thickness of about 5 to about 15 mils.

6. The improvement of claim 1 wherein said thickness of said closed cellular layer is about 2 to about 5 times the thickness of said film.

7. The improvement of claim 1 wherein said thickness of said closed cellular layer is about 3 times the thickness of said film.

8. The improvement of claim 1 wherein said film is on the outside of said sleeve.

9. The improvement of claim 1 wherein said sleeve is decorated.

10. The improvement of claim 1 wherein said uniaxially oriented sleeve is formed from a laminated composite capable of shrinkage in the circumferential direction at least about 5 times the amount of shrinkage in the axial direction.

11. The improvement of claim 1 wherein said sleeve has finger openings.