AU2011101312A4 - A tray and blank - Google Patents

Abstract

- 14 The present invention relates to a paper tray product and a blank for making the paper tray product. The tray can be used for baking a food product. The tray includes a 5 base, upright side walls, upright end walls, wherein side wall flaps extending from the side walls form part of the end walls, locking tabs extend from the flaps, and the end walls include slots that receive the locking tabs so as to releasably hold together the end walls and the side walls 10 in upright positions at corners of the tray. The flaps have two sub-panels that are folded into overlapping relationship and bonded together so to provide a stiffened construction. The stiffened flaps enable the tray to have a height of less than 50mm. 2880945.1 (GHMatters) POS14.AU 12110/11 Figure 4 2947940_2 (GHMaetem P88l4.AU 27/09111

Description

AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION Innovation Patent Applicant (s): Amcor Limited Invention Title: A TRAY AND BLANK The following statement is a full description of this invention, including the best method for performing it known to me/us: -2 A TRAY AND BLANK FIELD OF THE PRESENT INVENTION The present invention relates to a paper tray product for baking food products, such as cake. 5 The present invention also relates to a blank for forming the paper tray product. BACKGROUND OF THE PRESENT INVENTION It should be understood that references to existing baking trays in this specification is not to be taken as an 10 admission that the existing baking trays constitute part of the general knowledge of a person skilled in the art in Australia or overseas. Bakeries often cut baked food products, such as cakes, into smaller portions for sale at retail outlets. For 15 commercial reasons, it is important that the cut portions be a uniform size and shape. Typically, bakeries cut baked products using precision cutting equipment, such as sonic and laser cutters, which are able to cut the products with a high degree of dimensional accuracy and produce sharp 20 well-defined cuts. However, in order to produce cut portions of uniform size and shape it is important that the as-baked products be dimensionally accurate. The as baked shapes of the products are directly related to the shapes of the trays in which the products are baked. 25 There have been proposals to use cardboard baking trays that have varying dimensional accuracy. The better trays have high dimensional accuracy as they enable portions of suitable size and shape to be cut from the baked product. The end and side walls of cardboard trays are often held 30 together by flaps extending from one wall having locking tabs that are received by slots formed in an adjacent wall. In our experience, as the height of the wall increases, the locking tabs and slots increase in size which improves the durability of the side and end wall 35 construction. A limitation is therefore when a cardboard baking tray having lower side and end walls is required, for example side walls of less than 50mm, the structural soundness of the tray can become an issue. In the worst case scenario, the tray can fail during the cooking 40 process. 2880945_1 (GHMatters) P8148.AU 12/1011 - 3 An object of the present invention is to provide a paper tray product that is capable of producing baked products with a high degree of dimensional accuracy and a range of side wall heights. 5 SUMMARY OF THE PRESENT INVENTION The present invention relates to a paper tray product for baking a food product in the tray, the tray includes a base, upright side walls, upright end walls, wherein side wall flaps extending from the side walls form part of the 10 end walls, locking tabs extend from the flaps, and the end walls include slots that receive the locking tabs so as to releasably hold together the end walls and the side walls in upright positions at corners of the tray, and the flaps have two sub-panels that are folded into overlapping 15 relationship and bonded together to have a stiffened form. An advantage of the present invention is that the flaps have a stiffened form compared to flaps comprising a single sub-panel. In our experience, this enables that the height of the flaps, the side wall and end walls of 20 the tray to be reduced. This is advantageous when baking lower profile products. Throughout this specification the term "paper tray product" or variations thereof include any fibrous material that can be made in sheets such as, but by no 25 means limited to paper, cardboard, fluted materials including single and double sided fluted cardboard, corrugated cardboard, and laminations of any of the above mentioned materials. The fibrous material may include synthetic fibre, but more typically includes natural fibre 30 such as cellulosic, hemp, cotton and alike. The stiffened flaps may allow the height of only one, or both of, the side walls and the end walls, to have a height of less than 50mm, and suitably in the range of 25 to 50mm, and even more suitably approximately 30mm. In 35 our experience, the flaps and locking tabs of the existing trays are unsuitable for trays having walls of less than 50mm because the flaps buckle and twist under load which can cause the walls to become unlocked. The side walls include an inner section and an outer 40 section that are separated by a fold line, and one of the sub-panels extends from each of the inner and outer sections and the sub-panels are folded into overlapping relationship by the inner and outer sections being folded 280945_1 (GHMatters) P814.AU 12110/11 - 4 along the fold line. The locking tab may extend from either one or both of the sub-panels. The sub-panels may be folded into overlapping relationship when the inner and outer sections of side wall panels are folded into 5 overlapping relationship. In an alternative embodiment, the two sub-panels could extend from one of the side walls, in which one of the sub-panels extends from the other sub-panel which extends from the side wall, and the sub-panels are fold into 10 overlapping relationship. The locking tabs may extend from only one, or both, of the sub-panels. Suitably, the locking tabs and slots hold the side walls and the end walls in upright positions with the corners of the tray and, therefore, the corners of the baked food 15 product produced in the tray being straight and squared. Each side wall of the tray may be inwardly concave along its length between the end walls so that the side walls can flex outwardly to form side walls that are perpendicular to the base and perpendicular to the end 20 walls as the food product in the tray expands during baking. The locking tabs and slots holds together the end walls and the side walls of the tray so that the end walls and the side walls can be folded outwardly and downwardly to 25 provide access to the food product that has been baked in the tray. Each side wall flap may include at least one locking tab that extends from an upper edge of the side wall flap. The tray may include gusset corners in a lower section of 30 the tray. Suitably, the gusset corners extend no more than one third of the height of the tray. The present invention also provides a blank for forming the above-described paper tray product, the blank includes 35 a series of panels separated by fold lines and the panels include (a) a base panel that is adapted to form the base of the tray, 2880945_1 (GHMatters) P88148AU 12/10/11 -5 (b) side wall panels adjoining the base panel along opposite sides of the base panel that are adapted to form the upright side walls of the tray, (c) end wall panels adjoining the base panel at 5 opposite ends of the base panel, (d) folding sub-panels that adjoining the side wall panels at opposite ends of the side wall panels, wherein the sub-panels are adapted to be folded into an overlapping relationship and bonded together to 10 form the side wall flaps, and wherein when assembled into the tray the end wall panels and the side wall flaps are adapted to form the end walls of the tray, and (e) locking tabs adjoining the side wall flaps and 15 the end wall panels include slots that receive the locking tabs. The side wall panels may include an inner section and an outer section that are separated by a fold line, and the folding sub-panels adjoin each of the inner and outer 20 sections of the side wall panels. The locking tab may extend from either one or both of the sub-panels. The present invention also provides a method of forming the above-described tray from a flat blank. In accordance with the method, an upper edge of each side 25 walls of the tray is formed by folding an outer (upper) section of the side wall panel outwardly and downwardly against an outer surface of an inner (lower) section of the side wall panel and gluing or otherwise holding the folded upper section against the outer surface. 30 Folding the outer and inner sections into overlapping relationship can also overlap the sub-panels extending from the outer and inner sections. The sub-panels can then be glued together to form the side wall flaps. The side walls may then be formed by folding the side wall 35 panels upwardly at the fold lines that separate the side wall panels and the base panel. Thereafter, each end wall is formed by (a) folding the end wall panels at that end upwardly at the fold line that separates the end wall panels and the base panel, and (b) 40 folding the side wall panels at each end inwardly at the 288045_1 (GHMatters) P88148.AU 12/10111 -6 fold lines that separate the base panel and the side wall panels folding the side wall flaps formed by the sub panels and form at least part of the ends walls of the tray. 5 The action of folding the side wall flaps inwardly has the effect of bringing the upstanding side wall panels of the tray into contact with side edges of the upstanding base flap and thereby forming the corners between adjacent side and end walls. 10 The method may include inserting the locking tabs of the side wall flaps into the slots in the end wall panels when the base and side wall flaps are in folded positions and thereby holding the side wall panels against the end wall panels. 15 The locking tabs and slots may be formed so that the side wall panels at each end of the tray are pulled inwardly towards each other and thereby force the side wall panels into close contact with the side edges of the upstanding end wall panels. This feature contributes to forming 20 straight and squared corners between the side and end walls. An upper edge of each end wall of the tray is formed by folding an upper and outer section of the end wall panel outwardly and downwardly against an outer surface of inner 25 and lower sections of the side wall flaps. Suitably, adjacent end wall panels and side wall panels are partly joined together by gusset panels that form gusset corners in a lower section of the tray. The gusset corners prevent liquids in a baking mix and generated 30 during baking a food product from escaping from the tray. By confining the gusset corners to the lower section of the tray, the gusset corners do not interfere with the close contact between adjacent side and end walls at these corners of the tray that is achieved with the above 35 described arrangement of the base and side wall panels. Ideally, the gusset corners extend no more than one third of the height of the tray. The applicant has found that the above-described tray, and more particularly the end wall construction of the 40 upwardly folded end panels and the inwardly folded side wall panels are held together by the described locking tabs and slots, makes it possible to securely hold the 288094_1 (GHMattemr) P88148.AU 12110/11 - 7 side walls and end wall of the tray having a height above the base of 50mm or less. In addition, the side and end walls can be held with straight and squared corners between the side walls and the end walls of the tray. 5 In addition, the applicant has found that the locking tabs and slots facilitate quick and easy erection of the tray from the flat blank. In addition, the locking tabs and slots can be quickly and easily unlocked so that one or both end walls can be 10 "unfolded" to facilitate removal of cut portions of baked products from the tray and can then be "re- folded" and locked to re-form the end wall or walls to store remaining cut portions in the tray. The slots in the end wall panels may be positioned so that 15 the slots are on the upper edges of the end walls.. The present invention also provides a method of baking a food product in the above-described tray and thereafter at least partially packaging the baked food product which includes depositing a predetermined amount of unbaked food 20 product mix in the tray, baking the food product in the tray, and packaging the baked food product located in the tray so that the baked food product can be transported to an end use location. The method may further include cutting the baked food 25 product into smaller portions in the tray. The cut smaller portions may be substantially uniform in size and shape. BRIEF DESCRIPTION OF THE DRAWINGS The present invention is described further with reference 30 to the accompanying drawings, of which: Figure 1 is a perspective view of a fully assembled baking tray in accordance with a preferred embodiment of the present invention; Figure 2 is a perspective view of partially assembled 35 baking tray shown in Figure 1 which illustrates the arrangement of inner and outer sections of the side wall panels being folded in order to fold sub-panels extending from the inner and outer sections into overlapping relationship; 2880945_1 (OHMafters) P88148.AU 12110/11 - 8 Figure 3 is a perspective view of the partially assembled baking tray shown in Figure 1 which illustrates the arrangement of the outer section of the side wall panel being folded onto a inner section 5 of the side wall panel so that sub-panels are overlaid to form a reinforced side wall flaps and with a locking tab of the side wall labs received by a slot formed in the end wall panels; and Figure 4 is a top plan view of a blank for forming 10 the tray shown in Figures 1 to 3. DETAILED DESCRIPTION The paper tray product 1 shown in Figure 1 is formed from corrugated or any other suitable carton board which has (a) a bleached lining on the surfaces of the board that 15 form the interior and an upper section of the exterior of the box, and (b) a heat resistant polyolefin or other suitable coating on the bleached lining. The tray 1 is orthogonal with a rectangular base 5, upright side walls 7, and upright end walls 9. 20 The side walls 7 and the end walls 9 are folded outwardly so that the upper edges of these walls form generally smooth surfaces. The lower sections of the corners between adjacent side and end walls 7, 9 are formed as gusset corners to prevent 25 the escape of liquids from the tray 1. These gusset corners extend only part way up the height of the tray. As is described in more detail hereinafter, the tray is formed so that the side walls 7 and the end walls 9 are held together by flaps 10 formed by sub-panels 10a and 10b 30 extending from inner and outer sections of the side wall panels 7a and 7b respectively, and the sub-panels 10a and 10b are folded into overlapping relationship and bonded together using and suitable means, including but by no means limited to hot and cold adhesives, double sides tap 35 or staples. This construction ensures that the flaps 10 to have sufficient rigidity to retain the locking tabs 17 in position when the height of the flaps 10 is reduced, for example, when the overall height of the carton is 50mm or less. This can be important consideration in terms of 40 minimise wastage when the baked goods do not require higher side walls. 280945.1 (GHMafters) P88148.AU 12/10/11 -9 In addition, the tray 1 is also formed so that (a) the base 5 and the side walls 7, (b) the base 5 and the end walls 9, and (c) the side walls 7 and the end walls 9, are straight and square. This construction ensures that a 5 baked product produced in the tray has straight and squared corners and straight sides and therefore has a high degree of dimensional accuracy. This can be an important consideration in terms of cutting the baked product into portions that have a uniform size and shape. 10 In addition to the above, the side walls 7 of the tray 1 are inwardly concave along the length of the side walls by a small amount to accommodate outward bulging of the side walls as a food product is baked in the tray. The tray 1 is formed by folding the corrugated board blank 15 shown in Figure 4. One face of the blank has the above described bleached lining and heat resistant polyolefin coating on the bleached lining. With reference to Figure 4, the blank 20 includes a series of fold lines 11 that define a series of panels. The 20 panels include a base panel 5 that forms the base 5 of the tray 1. The panels also include inner (lower) side wall panels 7a that adjoin the base panel 5 at opposite sides of the base panel 5 and outer (upper) side wall panels 7b that adjoin the lower side wall panels 7a. These side wall 25 panels 7a, 7b form the side walls 7 of the tray 1. The panels also include end wall panels 9a, 9b for forming the end wall 9 of the tray 1, the end wall panels include inner (lower) end wall panel 9a that adjoins the base panel 5 at opposite sides of the base panel 5, and an 30 outer (upper) end wall panels 9b that adjoin the inner wall panels 9a, and sub-panels 10a and 10b which form the side wall flaps 10 that adjoin the side wall panels 7a and 7b at opposite sides of the side wall panels 7. These panels 9a, 9b, 10a and 10b form the end walls 9 of the 35 tray. The fold lines 11 between the pairs of the end wall panels 9a, 9b are scored part way along their length to form slots 15. In addition, the side wall flaps 10 include outwardly projecting tabs 17. As is described hereinafter, 40 the slots 15 and the tabs 17 form locking assemblies that hold the end panels 9a and 9b, sub-panels 10a and 10b which together form side wall flaps 10 form the end walls 9 of the tray 1. 2830945_1 (GHMatters) P88148AU 1210111 - 10 The panels also include gusset panels 21 that partly join together adjacent end wall panel 9a and side wall flaps 10a to form the gusset corners 13. The tray 1 is formed from the blank 20 by firstly folding 5 the side wall panels 7b about the fold lines 11 that separate the pairs of side wall panels 7a and 7b so that the non-bleached faces of the side wall panels 7b contact the non-bleached faces of the side wall panels 7a and thereafter gluing the faces together. In addition, this 10 action also aligns the non-bleached faces of the side walls flaps lob with the non-bleached faces of the side wall flaps 10, and the flaps 10a and lOb bonded together. This step is shown schematically in Figure 2. These steps produce side walls 7 with smooth upper edges and stiffened 15 flaps 10. The next step in erecting the tray 1 is to fold, in the direction of arrow A in Figure 2, the glued together side wall panels 7a, 7b and glued together side wall flaps 10 upwardly about the fold lines 11 that separate the side 20 wall panels 7a and the base panel 5 to form the upstanding side walls 7 of the tray 1. Thereafter, the end walls panels 9a, 9b are folded upwardly and inwardly to upstanding positions and the side wall flaps 10 are folded inwardly against the outwardly 25 facing surfaces of the upstanding end wall panels 9a. This step has been completed in Figure 2. This movement of the side wall flaps 10 brings the upstanding side wall panels 7a into close contact with the side edges of the upstanding end wall panels 9a and forms the corners 30 between adjacent side walls 7 and end walls 9. The end wall panels 9a and side wall flaps 10 are held in contact by the above-described slots 15 receiving the locking tabs 17 extending from the end wall panels 9a and 9b. The locking tabs 17 are received by the slots by 35 folding the side wall flaps 10 in the direction of arrow B shown in Figure 2. The positions of these components of locking assemblies are selected so that a step of folding the end wall panels outwardly and downwardly positions the slots 15 to form part of the upper edges of the end walls 40 9 and positions the locking tabs 17 to extend upwardly through the slots 15 so that the locking tabs 17 are retained by the slots, as shown in Figure 3. 288094S1 (GHMatters) P88148.AU 12110111 - 11 The sub-panels 10a is illustrated as having one of the locking tabs 17, while the side wall flap 10b does not include a locking tab. However, it will be appreciated that the locking tabs 17 can be provide on both sub-panels 5 10a and 10b, and aligned and glued together. The positions of the slots 15 and the locking tabs 17 are also selected so that it is necessary to force the side wall flaps 9c inwardly in order to align the locking tabs 17 carried by these flaps 10 to be received in the slots 10 15 and this inward movement further promotes close contact between the side walls 7 and the side edges of the upstanding end wall panels 9a that form the corners. The above-described tray can be formed without difficulty on conventional cutting, folding and gluing machinery. 15 In use in a bakery, a predetermined amount of unbaked food product mix is deposited in the above-described tray and the tray and food product mix are thereafter placed in an oven and the food product is baked in the tray. At the end of a required baking time, the tray and baked food product 20 are removed from the oven and the food product is allowed to cool to a required extent in the tray. Thereafter, the cooled food product is cut into smaller portions of uniform size and shape using laser or other suitable precision cutting equipment. At this point, the tray forms 25 part of the distribution packaging of the now cut baked food product. The packaged product is ready to be transported to an end use location for use at the location, for example after the addition of a lid on top of the carton, or the packing of the lidded trays inside 30 secondary packaging such as corrugated packaging Those skilled in the art of the present invention will appreciate that may variations and modification may be made to the preferred embodiment without departing from the spirit and scope of the preferred embodiment. 35 For example, it is possible that a pair of sub-panels joined to each other may extend from only one, or both, of the side wall panels 10a and 10b and that the sub-panels may be folded into overlapping relationship to form a side wall flap having two layers of the sub-panels in order to 40 stiffen the side wall flap. 28804_1 (OHMatters) P8814.AU 12/10/11

Claims (5)

1. A paper tray product for baking a food product, the tray includes a base, upright side walls, upright end 5 walls, wherein side wall flaps extending from the side walls form part of the end walls, locking tabs extend from the flaps, and the end walls include slots that receive the locking tabs so as to releasably hold together the end walls and the side walls in upright positions at corners 10 of the tray, and the flaps have two sub-panels that are folded into an overlapping relationship and bonded together to have a stiffened form.

2. The tray according to claim 1, wherein the side walls include an inner section and an outer section that are 15 separated by a fold line, and one of the sub-panels extends from each of the inner and outer sections and the sub-panels are folded into overlapping relationship by the inner and outer sections being folded along the fold line.

3. The tray according to claim 1 or 2, wherein the Bide 20 walls and the end walls, and therefore, the side wall flaps have a height of less than or equal to 50mm.

4. A blank for forming the paper tray product according to any one of the preceding claims, the blank includes a series of panels separated by fold lines and the panels 25 include (a) a base panel that is adapted to form the base of the tray, (b) side wall panels adjoining the base panel along opposite sides of the base panel that are adapted to 30 form the upright side walls of the tray, (c) end wall panels adjoining the base panel at opposite ends of the base panel, (d) sub-panels adjoining the side wall panels at opposite ends of the side wall panels, wherein the 35 sub-panels are adapted to be folded into an overlapping relationship and bonded together to form the side wall flaps, and wherein when assembled into the tray the end wall panels and the folding sub panels are adapted to form the end walls of the tray, 40 and 288094_1 (GHMatters) P88148.AU 12/10111 - 13 (e) locking tabs adjoining the side wall flaps and the end wall panels includes slots that receive the locking tabs.

5. The blank according to claim 4, wherein the side wall 5 panels includes an inner section and an outer section that are separated by a fold line, and one of the sub-panels are adjoined to each of the inner and outer sections of the side wall panels. 10 28809451 (GHMatters) P88148.AU 12/10/11