NZ533776A - Hot/warm fill container - Google Patents

Abstract

A polymeric hot fill or warm fill container has a neck finish, a base and sidewalls between the neck finish and the base. A vacuum absorbing region in the sidewall has three vacuum absorbing panels spaced about the container so that when a vacuum is applied to the inside of the container the majority of the vacuum is absorbed the vacuum panels and the vacuum absorbing region substantially triangulates in transverse section.

Description

533776 Patent Form No. 5 NEW ZEALAND Patents Act 1953 COMPLETE SPECIFICATION TITLE: HOT/WARM FILL CONTAINER INTELLECTUAL PROPERTY OFFICE OF N.Z 2 8 JUN 2004 RECEIVED We ACI OPERATIONS PTY. LIMITED, an Australian company of 36 Burwood Road, Hawthorn, Victoria, 3122, Australia, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: 4003q 2 Field of the Invention The present invention relates to packaging containers, in particular to polymeric hot fill or warm fill bottles. It will be convenient to describe the 5 invention with reference to bottles for filling with beverages although it will be appreciated that the invention may have wider application.

Background of the Invention Polymeric bottles suitable for hot or warm filling with beverages have been used for many years. The term "hot fill" generally refers to filling of a container with a liquid at 80°C or above and the term "warm filling" generally refers to filling a container with a liquid at 60°C or above. For convenience in this description where the term "hot fill" or "hot filling" is used, this will equally 15 apply to warm filling.

Beverages such as non-carbonated sports drinks, juices and waters in particular may be hot filled or warm filled in bottles to ensure the sterility of the beverage. Once filled, the bottle is then sealed with a closure and cooling to 20 ambient temperature then takes place.

During cooling, the liquid will contract and creates a partial vacuum inside the bottle. It is known in the art that it is desirable to design panels in the bottle which can absorb at least some of the vacuum so as to avoid bottle 25 distortion which is both aesthetically displeasing and functionally render the w:\erin\mps\species\complete filing - 697497.doc bottle unusable. Distortion of a bottle will generally be seen by consumers as undesirable and may suggest a defect in the product.

The most commonly used polymer for manufacturing such bottles is a polyester such or polyethylene terephthalate ("PET") and it is desirable to use the minimum possible amount of material in each bottle for many reasons including weight and cost. The imperative to minimise material in each bottle comes at the expense of bottle strength so bottle design may be critical in balancing these two competing requirements.

A commonly observed defect in hot fill bottles is a tendency of the sidewalls to collapse in an uncontrolled manner even where vacuum absorbing panels have been designed into the bottle shape. Such defects may be caused by inherent lack of vacuum strength in the design of the bottle, or incorrect material distribution in the bottle.

Many existing hot fill bottles also rely upon the vacuum absorbing panels as a surface over which the label can be applied. This presents an uneven > surface to the consumer to grip which may present an unpleasant or insecure tactile sensation.

It is an object of the present invention to provide a polymeric container with enhanced and controllable vacuum absorption capacity and which may adopt a more stable configuration under vacuum compared to other vacuum panel constructions. w:\erin\mps\species\complete filing - 697497.doc 4 It is a further object to provide a polymeric container having a sizeable label-bearing surface which doesn't include vacuum panels under the label-bearing surface.

Summary of the Invention \ In one aspect of the invention there is provided a polymeric hot/warm fill container having a neck finish 10 a base sidewalls between said neck finish and base and having a vacuum absorbing region having three vacuum absorbing panels spaced radially about said container such that when said vacuum is filled with a hot/warm liquid and sealed, as said liquid cools said vacuum panels deform and the vacuum region takes on a 15 more triangular configuration in transverse section.

The neck finish and base may be of any suitable configuration known in the art.

The sidewalls extend between the neck finish and base and have a vacuum absorbing region with three vacuum absorbing panels, which are preferably spaced equally around the container, i.e. radially at 120° to each other around the sidewall. The surface of the vacuum absorbing panels outside the container may be convex when no vacuum is applied to the inside of the w:\erin\mps\species\nz13689_04.doc INTELLECTUAL PROPERTY OFFICE OF IM.Z 2 7 JUL 2005 RECEIVED container and may deform inwardly towards a less convex shape or even adopt a flat or concave shape when a vacuum is applied to the inside of the container. Similarly the wall of each vacuum panel may initially be slightly concave, and then becomes more concave when it absorbs the vacuum.

In another embodiment each entire vacuum panel may be joined to its surrounding sidewall region by a flexible peripheral hinge. In this embodiment the profile of the main wall of each vacuum panel may remain relatively unchanged when the vacuum panel is absorbing the vacuum in the container, 10 and the vacuum is absorbed by the movement of the entire vacuum panel about the hinge, rather than progressive deformation of the wall of each vacuum panel for example, from a convex profile to a less convex profile as discussed above.

In the course of absorbing a vacuum inside the container, the vacuum 15 absorbing region, in transverse section, takes on a more triangular configuration. The vacuum absorbing region may be slightly triangular when no vacuum is applied, but that degree of triangulation will increase when vacuum is applied and absorbed by the vacuum panels. Preferably such triangulation is substantially regular about all three vacuum absorbing panels so that they each 20 move substantially equally towards a central longitudinal axis of the container.

In one embodiment the angular extent of each vacuum panel, i.e. the arc described by each vacuum panel of the bottle in transverse section is between 60° and 80°, more preferably between 65° and 75° although it should be noted 25 that vacuum panels having angular extents outside these ranges may be useful. w:\erin\mps\species\complete filing - 697497.doc 6 The shape of each vacuum panel need not necessarily be substantially rectangular such that its angular extent is consistent in cross-section along its length. For example, each vacuum panel may be oval in side elevation or arch shaped. In such embodiments, the preferred angular extents are measured at 5 the widest part of each vacuum panel.

Preferably there are provided regions of the vacuum absorbing region intermediate adjacent vacuum panels which assist to maintain the structural integrity of the vacuum absorbing region when a vacuum is applied to the inside 10 of the container. Most preferably each intermediate region includes one or more columns which collectively act together to form a rigid cage between which the vacuum panels may deform in a controlled manner while the bottle maintains its height and top load bearing capacity. The columns may act as the 3 apexes or corners of the triangulating vacuum absorbing region which remain 15 stationary as the vacuum panels contract inwardly in absorbing vacuum inside the bottle.

In one embodiment each intermediate region includes a window between a pair of columns and the windows may absorb some vacuum, although to a 20 lesser extent than the vacuum panels. Surprisingly, when 3 windows are provided which are visible through an opposite vacuum panel, the optical characteristics of the bottle, especially when filled with a colourless liquid such as water, are such that the bottle takes on a prismatic effect and is highly visually appealing. This may add to the consumer aspect of such a container 25 which may enhance sales of the product packaged in such a bottle. w:\erin\mps\species\complete filing - 697497.doc 7 In conventional hot/warm fill containers, the conventional place to apply a label is directly over the vacuum absorbing region. The vacuum panels below the label generally present an uneven surface so when a consumer grips the 5 label area, the uneven surface is felt. As the label is flexible over the uneven surface, the consumer may perceive an unpleasant or insecure grip on the bottle. With the present invention however, there may be provided a separate body portion with no vacuum panels which presents a uniform, even surface to which a label can be applied. In one embodiment the body portion is positioned 10 between a waist which is below the vacuum absorbing region, and the base. In another embodiment the body may be positioned closer to the neck finish than the vacuum absorbing region.

The present invention also presents an advantage that should the 15 vacuum absorbing region be gripped by a consumer, the triangulate shape presents a convenient and factually pleasing form to be gripped.

It will now be convenient to describe the invention with particular reference to the preferred embodiment shown in the drawings in which: 20 Figures 1 & 2 are side elevations of one preferred embodiment of a bottle in accordance with the present invention.

Figure 3 is a transverse section along the line C-C of Figure 1.

Figures 4 & 5 are side elevations of another preferred embodiment of a bottle in accordance with the present invention.

Figure 6 is a transverse section along the line A-A of Figure 4. w:\erin\mps\species\complete filing - 697497.doc 8 Figure 7 is a side elevation of yet another embodiment of a bottle in accordance with the present invention.

In Figure 1, bottle 1 includes a neck finish 3, a base 5, a vacuum 5 absorbing region 7, a waist 9 and a body 11. Neck finish 3 is a standard neck finish known for polymeric bottles and is formed as part of a preform from which bottle 1 is blown. Base 5 is similarly of any standard base configuration known for polymeric bottles.

Shoulder region 13 is provided below neck finish 3.

Vacuum panel 15 is substantially oval shaped and extends partly into shoulder region 13 at its upper extent and terminates proximate waist 9 at its lower extent. Vacuum panel 15 shown is typical of the three vacuum panels provided at equal spacings around vacuum absorbing region 7. The perimeter 17 of vacuum panel 15 is joined to its surrounding area of the vacuum absorbing region 7 by hinge 19, which allows vacuum panel 15 to move inward towards central longitudinal axis 21 of bottle 1 while the remainder of vacuum absorbing region 7 does not move.

Columns 23 and 25 are provided between vacuum panels 15 and 15a and are typical of similar columns provided around the remainder of bottle 1 between adjacent vacuum panels. Columns 23 and 25 extend across the entire length of the vacuum absorbing region 7 from waist 9 to shoulder region 13.

Collectively the columns act as a rigid cage-like structure that allows movement w:\erin\mps\species\complete filing - 697497.doc of the 3 vacuum panels between adjacent columns to a more triangular shaped cross-section while maintaining the structural integrity of the vacuum absorbing region 7 and hence the bottle 1. It is essential that the bottle maintains its top load bearing capacity so that layers of bottles can be stacked on top of each other without collapsing bottles on the lower layers. It is also essential that the bottle remains a regular, aesthetically pleasing shape as designed, rather than deforming in an irregular way. In this respect the controlled collapsing of the vacuum panels to a more triangular bottle cross-section is supported by the ability of the columns to remain relatively stationary.

Window 27 is a typical of three such windows which are positioned between columns 23 and 25. Window 27 may be embossed with a trade mark or other indicia (not shown) relating to the bottle contents and when bottle 1 is filled with a transparent fluid such as water, window 27 may be visible through the diagonally opposite vacuum panel. In this arrangement light refracted through the interior facets of the vacuum absorbing region and transmitted through the transparent vacuum panels enhances the appearance of the bottle 1 though a prismatic effect. Further, the curvature of the vacuum panels 15, 15a may act as a lens to focus such retracted light to further enhance the prismatic effect.

Waist 9 comprises a reinforcing ring 29 which strengthens the bottle and isolates the body from the features of vacuum absorbing region 7. w:\erin\mps\species\complete filing - 697497.doc Body 11 is adapted to receive a label (not shown) such as wrap around or a shrink-wrap label or the like. Body 11 includes a plurality of reinforcing rings typically shown as 31 which act to strengthen sidewalls 33 of body 11 against crushing or vacuum deformation.

Turning to Figure 3, vacuum panel sidewalls 35 a, b & c are equally spaced about the bottle 1. Vacuum panel sidewalls 35 a, b & c are shown slightly convex relative to the outside of bottle 1 when no vacuum is present although they may equally be more or less convex than is shown, they may be 10 substantially linear in cross-section between hinges shown typically for panel 35c as 39 and 41 or they may be concave. Irrespective of the shape of sidewalls 35 a, b & c, when a vacuum is applied to the interior 43 of bottle 1, the sidewalls will tend to move inwardly in the direction of arrows 45 a, b & c towards centre point 47 which is a point along longitudinal axis 21. The 15 sidewalls 35 a, b & c thus collapse in a controlled manner to triangulate the vacuum absorbing region. It has been found that collapse of vacuum panels to a triangular shape results in a more stable arrangement and the vacuum forces may be equally shared across three vacuum panels compared with bottles having more vacuum panels.

Figures 4 and 5 depict an alternative arrangement for a bottle 49 of the present invention. The features of neck finish 3, base 5, waist 9 and body 11 are substantially identical to that depicted in Figures 1 and 2. w:\erin\mps\species\complete filing - 697497.doc 11 Three vacuum panels, two of which are shown as 51 and 53 are located at equal spacings around the vacuum absorbing region 55. The panels 51 and 53 extend at their upper regions 57 and 59 from inside shoulder region 13 and terminate at waist 9. As shown in Figure 6, the vacuum panels 51 and 53 are 5 outwardly convex in their resting state when no vacuum is applied to the inside of the bottle, although as described above with reference to Figures 1 and 2, the vacuum panels may be linear or concave in their resting state.

Columns 61 a, b and c are provided between each pair of adjacent 10 vacuum panels 51, 53 and 52. The approximate angular extent 63 of each vacuum panel of which vacuum panel 52 is typical is about 74°.

In this embodiment, lines of juncture 65 a-f allow relative movement between vacuum panels 51, 52 and 53 and columns 61 a, b & c when a 15 vacuum is applied to the inside of the bottle so that panels 51, 52 and 53 will move towards longitudinal axis 67, shown as centre point 69 in Figure 6, in the direction of arrows 71 a, b & c. The vacuum absorbing region 55 will thus triangulate when absorbing such a vacuum.

In the bottle shown in Figure 7, the vacuum absorbing region 7 is located closer to base 5 than in the other bottles illustrated. Vacuum panel 73 is typical of the three vacuum panels spaced circumferentially around the sidewall of the bottle 1. Panel surface 75 is reinforced by ribs 77 a, b &c. Column 79 is typical of the three columns spaced circumferentially around the sidewall of the bottle.

When the bottle 1 is subjected to an internal vacuum, column 79and the two w:\erin\mps\species\complete filing - 697497.doc 12 other similar columns will remain substantially stationary when vacuum panels 73 and the two other similar vacuum panels move inwardly to absorb the vacuum.

Bottles of the present invention may be made from any suitable material known in the art but is preferably a thermoplastic polymer such as polyethylene terephthalate, polyethylene or the like. Preferably bottles of the invention are made by blow moulding.

Finally it is to be understood that various additions, modifications and/or alterations may be made without departing from the spirit or ambit of the present invention. w:\erin\mps\species\complete filing - 697497.doc

Claims (12)

13 THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A polymeric hot/warm fill container having a neck finish 5 a base sidewalls between said neck finish and base and having a vacuum absorbing region having three vacuum panels spaced radially about said container such that when said container is filled with a hot/warm liquid and sealed, as said liquid cools said vacuum panels deform and the vacuum absorbing region 10 substantially triangulates in transverse section.

2. A container according to claim 1 wherein each vacuum panel includes a portion which in transverse section has an angular width of between 60° and 80°. 15

3. A container according to claim 2 wherein the angular width is between 65° and 75°.

4. A container according to any one of claims 1 to 3 where said vacuum panels are equally spaced about said container. 20 25

5. A container according to any one of claims 1 to 4 wherein there are provided intermediate regions between each adjacent pair of vacuum panels which assist to maintain the structural integrity of said vacuum absorbing region when a vacuum is applied to the inside of the container.

6. A container according to claim 5 wherein each of said intermediate regions include one or more columns.

7. A container according to claim 6 wherein each intermediate region includes 30 a window between two columns which absorbs some vacuum.

8. A container according to claim 7 wherein said window is visible through the container when viewed through an opposite vacuum panel. w:\erin\mpsVspecies\nz13689_04.doc I 2 7 JUL 2005 1VED 14 the container when viewed through an opposite vacuum panel.

9. A container according to any one of claims 1 to 8 wherein said sidewalls further include a body portion separate from said vacuum absorbing region adapted to receive a label.

10. A container according to any one of claims 1 to 9 wherein said vacuum absorbing region extends from a shoulder below said neck finish to a waist region above said base.

11. A container according to claim 9 or 10 wherein said body portion is positioned between said waist region and said base.

12. A container substantially as hereinbefore described with reference to any one of the drawings. DATED: 25 June, 2004 PHILLIPS ORMONDE & FITZPATRICK Attorneys for: ACI Operations Pty Ltd w:\erin\mps\species\complete filing - 697497.doc