CA1136097A

CA1136097A - Tubular preform for packaging containers

Info

Publication number: CA1136097A
Application number: CA000334798A
Authority: CA
Inventors: Robert J. Heier; Stephen W. Amberg
Original assignee: Owens Illinois Inc
Current assignee: OI Glass Inc
Priority date: 1978-10-10
Filing date: 1979-08-30
Publication date: 1982-11-23
Also published as: AU515664B2; FR2438600B1; DE2938407A1; GB2038270B; JPS6020184B2; DE2938407C2; FR2438600A1; AU5152079A; NL7907459A; GB2038270A; JPS5579277A

Abstract

TUBULAR PREFORM FOR PACKAGING CONTAINERS

ABSTRACT OF THE INVENTION
A tubular preform is provided for assemblying bottles or other containers into a package. The bottles for an integral package are arranged in a group and the tubular preform is placed around the group. The tubular preform is formed from a lengthy sheet of flexible heat-shrinkable thermoplastic material which is a composite foam and film laminate with the preform having a thermal fusion seal extending in an axial direction. The preform is flat-folded with a pair of axial pleated folds in diametri-cally opposite sides and then double-folded centrally for use in multiple unit packaging of like containers. The preform has a primary orientation in a circumferential direction and a secondary orientation in an axial direction making it particularly useful when opened for heat shrinking around a group of like containers.
The tubular preform in heat-shrunken condition forms a tight package convenient for handling, shipment and use.

Description

BACKGROUND OF THE INVE~TIO~

I 1. FIELD OF THE INVENTION

I This invention relates to th~ art of making tubular ¦ sleeves suitable for application to an assembled group of con-I tainers, such as glass bottles and the like. ~he tubular sleeve ¦ constitutes novel banding material and structure especially ....... .;.. ! _ !

~ ' ' ' , .

113~097 1 I desirable for assemblying and heat-shrinking around the grouped containers so that the major exposed surfaces o~ such similar containers are held in tightly-constrained tangential relation.

2. DESCRIPTIO~ OF THE PRIOR ARq:

5 1 I~ is common practice to merchandise many items such as containers for soft drinks, beer and the like, in packages containing a number of containers with the package normally including a handle or other hand holding means to facilitate ¦ carrying the package. A most common package consists of a 10 ¦ relatively-rigid paperboard blank formed around a group of con- j tainers, normally six or eight, with the folded blank usually being interlocked with itself and the like containers in the ; Ipackage. The paperboard packages normally require partitions Ibetween individual containers, especially in the case of glass 15 Ibottles, to avoid surface-to-surface contact. These paperboard blank packages have not been entirely satisfactory in that they 'are relatively expensive and are comparatively difficult to form, i ¦ particularly with the high speeds required by modern filling, ¦Icapping and packaging machines.

20 I To overcome these and other deficiencies of the folded Ipaperboard blank, cans have recently been packaged by assemblying the cans with a multi-apertured carrier formed from a sheet of resilient plastic material with the beaded end of the cans each l being inserted through the apertures. The periphery of the 25 I,apertures grasp the sidewalls of the cans and are locked beneath ¦ the bead securely enough to permit carrying of the package by a ~i, }

I I .

I ~1360~7 1, 1 1 I handle or ~inger holes formed in a central portion of the resi-lient plastic carrier. Heretofore, it has not been considered practical to package bottles in this manner because the elon-~, gated neck and shoulder portion projecting upwardly from the 5 I cylindrical bod~ portion have made existing methods and apparatus for the retention o cans in a multi-pack impractical or unduly expensive for packaging bottles. Further, the relatively great distance over which the carrier must be moved in its application I onto the body portion of the bottles has made it necessary to install the carrier on successive bottles substantially simultan-eously to avoid excessive distortion and tearing of the plastic carrier. Also, the side surfaces of bottles require additional retention means such as an encompassing band to avoid surface-to-l~
l' surface impact of the bottles during handling, shipment and dis-15 ' assembly of the package. Such apparatus for packaging containerstis disclosed in U. S. Patent Mo. 3,509,68~ to ~ohl and Scribner, which patent is assigned to the same common assignee as the present invention.
i I More recently, the introduction of shrinkable plastic 20 I overwraps has occurred causing drastic changes in the paperboard ¦ packages of the past. The following U. S. patents are repres-entative of packages using plastic overwraps of various types.
Most of these disclosures are directed to various transparent I film-type non-foamed shrink wrap packages and to the use of 25 I prescribed handles, fingerholds and related supporting structures.
j The patents are:

li -3-Ii i ' 11360~7 '~
'.~
1 1 3,532,214 3,650,394 3,331,503

3,198,327 3,650,395 3,302,784 3,552,559 3,817,373 3,477,564 1 3,834,525 3,416,288 3,756,397 S ~ RE 28,535 3,747,749 3,217,874 . l Multi-container packages which utilize transparent I thermoplastic films are suitable for many applications; however, ¦ their use for packaging glass containers which contain light-I sensitive comestibles such as beer is undesirable. Also such 10 li films do not provide the desired level of impact protection fora multi-pack of glass containers. Further, such films can be I decorated with advertising information only with difficulty 1i ! ¦ requiring the use of supplemental labels or wrappers for product ¦ îdentification.

15 I The use of foamed polystyrene for shrink wrapping of multi-pack integral packages is disclosed in U. S. Patent 3,400,810. However, the foamed polystyrene taught by this patent is biaxially oriented and will shrink generally uniformly in I both directions. This type of overwrap in heat-shrunken conditio}
20 I exhibits generally the same strength properties in both directionc thus making expedient removal of the individual containers some-what difficult. With this material, it is also difficult to form ¦ end seals of the flaps at the package ends due to both axial and ¦
circ~mferential shrinkage of the overwrap.

1.

113609~ ' i Accordingly, it is an object of this invention to provide an improved tubular sleeve for assemblying bottles into packages for most convenient handling, shipment and use.

Il I
' Another object is to provide an improved tubular ¦ preform comprised of resilient heat-shrinkable thermoplastic material adapted to telescopically surround a group of assembled bottles to form an integral package upon shrinking for convenient ¦ handling and shipment.

10 ~ Another object is to provide an improved flexible heat-shrinkable tubular sleeve which is pre-oriented in both its circumferential and axial directions adapted to unique manu-¦ facture ana folding for its convenient shipment and subsequent luse in assemblying machines designed to open the sleeve and place ' 15 !the same telescopically around a group of bottles to form anintegral package. The sleeve upon shrinkage is strong and ¦provides cushioning protection to the surrounded bottles and yeL
is easily opened, is opaque to light for protecting the container !
contents, and is capable of being preprinted with information or decoration prior to application.

i Another object of this invention is to provide a pre-formed tubular banding material which is adapted to flat-folding with minimal overlap of its folds as well as with an axial thermal fusion seal, the sleeves being designed to be packaged and shipped in multi-unit packages for subse~uent opening and application to !
, .. , ~ . . ,,i. . . ., ~ . . .

~ 14698 ~1 113609q 1 I grouped similarly-shaped containers encompassing their major exteriorly-exposed surfaces.

¦ A further object is to provide tubular banding 1 material formed from flexib~e foamed sheet thermoplastic material 5 i which is heat-shrinkable having fold lines at opposite sides and a fusion seal along a bottom portion intermediate the side fold lines, the sleeve being adapted to uniform pile-type stacking for easy opening and usage. The tubular banding material j can thus be packaged flat in muiti-pack units for delivery and 10 ! use in conjunction with packaging machines adapted to moving spaced tightly-assembled groups of bottles through the apparatus. !

The tubular preformed sleeve of this invention is thus especially adapted for use with high speed filling and capping ~ machines to receive the filled, capped bottles issuing from such 15 , machines and form them into packages such as the conventional ¦ six-pack employed to merchandise soft drinks and beer. The bottles to be packaged are fed onto a horizontal belt conveyor in spaced groups each normally consisting of two parallel rows of three bottles each in upright side-by-side relation. The groups of bottles are carried by the conveyor past a sleeve-apply-ing position with the groups then being telescopically deposited in individual sleeves. Adjacent the sleeve-applying position, ¦ flexible tubular sleeves are fed from a magazine in flat-folded ~ condition, one at a time,onto an opening conveyor where they are i subsequently picked up and retained by retention arms followlng ¦~ which distention means serve to open the sleeves serially into 1' ~

~36~g7 generally rectangular configuration. The opened sleeves are then moved arcuately downwardly and along the bottle conveyor where the bottle groups are telescoped into the tubular sleeves for deposi-tion centrally therewithin. The sleeves containing the assembled bottles are then conveyed through a heat-shrinking tunnel oven where the sleeves are heat-shrunk tightly around the grouped bottles.
The sleeves are shrunken to a considerable extent around the major exposed surfaces of the bottles leaving only portions of the end bottles of the group slightly exposed.
The tubular sleeves of the present invention comprise a plastic overwrap which is opaque, prestretched and oriented, laminated composite material. The sleeves are primarily oriented in a circumferential direction and constitute a closed cellular, foamed, thermoplastic, polyolefin layer laminated to a non-cellular thermo-plastic polyolefin film. The sleeves in heat shrunken condition circumscribe the assembled containers and snugly engage the tops of containers in shrink-fit relation.
Thus, in accordance with the present teachings, a tubular preform article is provided for use in packaging a plurality of similar containers in tightly-held array. The preform article is comprised of heat-shrinkable flexible foamed opaque thermoplastic material of uniform wall thickness which is pre-stretched and oriented in both its circumferential and axial directions to facilitate substantial heat-shrinkage upon usage. A thermal fusion seal extends throughout the axial dimension of the tubular preform article and a decorative pattern is imprinted on the exterior surface of the preform article except in the area of the thermal fusion seal. A pair of pleated side folds is disposed , along the sides of the preform article to flatten the article and .. ~ ~

113f~09~7 an off-center transverse fold is provided wherein the top panel is folded on itself to place the article in double-folded flattened condition for pile-type stacking.
Further objects and advantages of the present invention will be apparent from the following detailed specification and reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic perspective view of the tubular sleeve manufacturing process and resultant folded sleeves.

With reference to the drawings, a sheet of thermo-plastic material having the aforesaid characteristics is taken as a blank 1 to be formed into a tubular sleeve 2. The sleeve 2 has a uniform wall thickness and is preferably comprised of a laminated polymeric olefinic thermoplastic material such as poly-ethylene. The composite material has one surface comprised of a layer of a closed-cell foamed olefin polymer firmly adhered to a non-cellular olefin polymeric film. The cellular foamed layer is preferably on the inside of the sleeve 2a and the non-cellular film layer is preferably on the outside of the sleeve 2b present-ing a smooth non-porous surface especially adapted to decorating.

~ 14698 11 113609t7 .
1 I The laminated composite material is impervious to air, light , and water and has a primary orientation in a circumferential direction when formed into a tubular sleeve. The material has , a secondary orientation in the axial direction when formed into ~ a sleeve. The composite material in sheet form has a bulk density ranging from about ~ to 30 pounds per cubic foot and particularly desirable tensile strength for practicing the ' present invention. The laminated foamed and film sheet should I have an overall thickness preferably ranging from about 0.004 I to 0.020 inch.
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The tubular sleeve is formed from a pre-stretched and oriented lengthy sheet or ribbon of cellular and non-cellular ¦ olefinic thermoplastic material which is preprinted or decorated on the smooth film side. The primary orientation of the material ¦ extends in major amount along the longitudinal or axial direction I of the lengthy sheet or ribbon, and preferably has a shrinkage ¦ of about 70% as formed. The sheet has a substantially-lesser ; shrinkage ranging from about 10 to 20% in the transverse directio I or across the sheet as formed.

20 , The lengthy ribbon or web of printed sheet material is normally wrapped into rolls for subsequent use. The printed rolls are sized to a prescribed width which is equivalent to the desired axial length of the tubular preform to surround the assembled bottles with the requisite end overhang. Thus the I sheet or ribbon of oriented preprinted stock having its primary or entation extending continuously in the lengthwise or machine 1~ t 1~3~i097 1 direction is taken as the starting material. The sheet in roll ¦ form is delivered onto a drum where the sheet is severed into , uniform lengths of prescribed width or axial dimensions. The ¦, length is slightly greater than the desired circumferential or ¦ radial dimension to loosely surround the assembled bottles ¦ transversely of the rows.

The blanks which are normally cut in succession from a roll are placed on individual mandrels and wound thereon and ¦ seamed by overlapping the trailing marginal end of the blank over ¦, its leading marginal end. The blank ends are united at the overlapped region by fusion, adhesion or other known methods to form a sleeve or tube of the material comprising a tubular preform. A preferred method of forming the seam 2c consists of i locally heating the two overlapped portions of material resting 15 1il in physical engagement, contacting the area with a pressure-applying heated seal bar, and with such heat and pressure forming a lineal fusion or heat seal.

I The seam 2c may also be formed by an adhesive com-'l patible with the sheet material. The seam extends continuously , and uniformly throughout the axial length of the sleeve as formed~
~ The overlapped ends of sleeve employed to form the seam are ¦ devoid of printing and decoration so that no intermediate materia7 will adversely affect seam formation.
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The newly-formed sleeve or tube is then flattened into i collapsed condition by the use of gusseted side folds 2d formed I I
j, -10- 1, ~` 11360g7 l I in the sleeve sides. The juxtaposed sides of the sleeve are moved inwardly to ~orm axially-extending pleats or gusset folds with their centerfold being near the central region of the sleeve sides. Thus three axial fold lines are employ2d to fold ~ each side upon itself with the middle fold projecting inwardly.
¦ The side folds are formed so that the bottom portion 2e of the ¦ sleeve is formed having a substantially-greater width than the top portion 2f. Both top and bottom panels are rectangularly I shaped with the parallel fold lines defining the edges of the top panel residing inwardly of the fold lines defining the bottom panel. Thus the folds comprising the side folds 2d do not I overlie one another with the sleeve in initially-flattened condition. The fold lines are such that they do not detract from the exterior appearance of the sleeve after opening and application to the assembled bottles.

After the side folds are formed as aforesaid, the top panel is folded near a central region 2g perpendicular to the sleeve axis. The transverse fold is made substantially off-cente~
so that the open end edges of the sleeve are spaced apart a substantial distance to facilitate easy opening of the sleeve.

The seam 2c preferably resides in a central bottom region of the flattened sleeve with the side folds on both sides thereof. The doubly-folded sleeves are readily adapted to being ~ packaged in multiple unit boxes, trays or envelopes containing ¦ a substantial number of similarly-folded and aligned sleeves, I the number being 200 to 500 per box, tray or envelope, for exampl~ .

l 14698 ~ ~3609~7 1 I The sleeve being formed of flexible laminated foam and film thermoplastic material is adaptable to withdrawal one-by-one from the multi-pack tray or box. The material being 1 flexible permits its being readily opened into tubular form for I introduction of the assembled bottles. The sleeve can be initially opened by various methods, such as by freeing the shorter folded portion of the outermost sleeve and pulling the sleeve from the pile-type stack by such free end.

I The sleeve thus folded is especially valuable for I feeding one at a time to a sleeve-applying machine. The fold lines of the tubular preform are preferably made by passing the ¦ preform through nip rolls 3 to flatten it; however, other methods may also be used such as pressing between flat plates. The sleeve is adapted to easy opening such as by diametrically-disposed vacuum cups just prior to its enclosing a group ofbottles telescopically.

In a preferred form of the invention, the sleeve has a ¦ length of about 11 1/2 inches and the top panel is folded having ¦ a width of about 5 5/8 inches, with the bottom panel being about ¦ 6 5/8 inches wide. The center fold is made with about one inch ¦ offset so that the end edges are disposed substantially apart.
This sleeve is especially valuable for surrounding a six-bottle group of standard size and shape non-returnable 12-ounce beer bottles for heat-shrinking into tight conformity. Only small equi-sized openings exist at the ends of the final package when the bottles are centrally located in tangential contact. ~o ~ 14698 1 11360g7 1 I movement of individual bottles occurs within the package after heat-shrinking the sleeve therearound.

The tubular sleeve results in no waste at the sleeve-; applying station of a packaging machine. Its usage in multi-I pack units provides an economical wrap for application by such machines with little or no downtime to exchange or replace rolls ~ of banding or labeling material. As desired, the sleeves may be I ¦ produced at a centralized location and shipped to many smaller ¦ operations to be expediously opened and applied to the selected containers.

Various modifications may be resorted to within the spirit and scope of the present invention as defined by the ~, appended claims.

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Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A tubular preform article for use in packaging a plurality of similar containers in tightly-held array, said preform article being comprised of heat-shrinkable flexible foamed opaque thermoplastic material of uniform wall thickness which is pre-stretched and oriented in both its circumferential and axial directions to facilitate substantial heat-shrinkage upon usage, the improvement comprising a thermal fusion seal extending throughout the axial dimension of said tubular preform article, a decorative pattern imprinted on the exterior surfaces of said preform article except in the area of said thermal fusion seal, a pair of pleated side folds disposed along the sides of said preform article to flatten said article, and an off-center transverse fold wherein the top panel is folded on itself to place said article in double-folded flattened condition for pile-type stacking.

2. A tubular preform article in accordance with Claim 1, wherein the thermal fusion seal is disposed in the bottom panel of said preform article.

3. A tubular preform article in accordance with Claim 1, wherein said pair of pleated side folds is comprised of inwardly and axially-extending gusseted folds with their central folds located near the centers of the article side panels.

4. A tubular preform article in accordance with Claim 1, wherein said pleated side folds are formed so that the bottom panel has a substantially greater width than the top panel for improved stacking and easy opening.

5. A tubular preform article in accordance with Claim 1, wherein said preform article is comprised of foamed polyethylene sheet having a thickness ranging from about 0.004 to 0.020 inch.

6. A tubular preform article in accordance with Claim 1, wherein said off-center transverse fold in the top panel is formed so that the flattened open-end edges of said article are disposed substantially apart.

7. A tubular preform article in accordance with Claim 1, wherein the several folds and fusion seal are properly aligned to permit double flat-folding of the article with minimal overlap of said folds and thermal fusion seal for improved stacking and dispensing of a pile-type stack of said articles.

8. A tubular preform article for packaging a plurality of similar containers such as glass bottles and the like in tightly-held tangential array, said preform article being formed from a lengthy sheet of foamed thermoplastic material which is flexible, opaque and heat-shrinkable as well as being pre-stretched and oriented in both its circumferential and axial dimensions to facilitate substantial heat-shrinkage upon usage, the improvement comprising an axially-extending thermal fusion seal disposed in the bottom portion of said preform article, a decorative pattern imprinted on the exterior surfaces of said preform article except in the area of said axially-extending thermal fusion seal, a pair of similar parallel gusseted side folds disposed along the juxtaposed sides of said preform article to flatten the same, said side folds forming a rectangular top panel which is substantially narrower than a rectangular bottom panel, and an off-center transverse fold wherein the top panel is folded on itself to place said article in double-folded flattened condition especially adapted to uniform pile-type stacking for ease of shipment and use.

9. A tubular preform article in accordance with Claim 8, wherein said pair of gusseted side folds are formed by folding the exterior surfaces of the sides inwardly into face-to-face pleated relation along off-center axial lines to flatten the said article.

10. A tubular preform article in accordance with Claim 8, wherein said preform article is comprised of foamed polyethylene sheet having a thickness of not less than about 0.004 inch.

11. A tubular preform article in accordance with Claim 8, wherein the said thermal fusion seal, gusseted side folds and top panel transverse fold are aligned to minimize overlapping when the article is double-folded to facilitate uniform stacking of a plurality of said preform articles and one-by-one dispensing of same from a pile-type stack.