AU2013205397A1 - Hinge arrangement for plastic container - Google Patents

Abstract

Described embodiments generally relate to a plastic thermoformed container, including: a base defining a support plane to support the container relative to another surface; a lid to close over the base; a hinge integrally formed with the base and the lid, the hinge frangibly joining the lid and the base along a first line of perforation and a second line of weakness, the first and second lines extending a length of the hinge and defining a hinge intermediate portion, wherein the hinge intermediate portion comprises a tab projecting in a first direction generally perpendicular to the support plane when the lid is closed over the base; wherein the tab is sized to readily allow it to be grasped and pulled to separate the lid from the base along at least the first line by pulling the tab in a second direction generally opposite to the first direction. ______ (V I' -; ~> I ~ K) f 0

Description

1 AUSTRALIA Patents Act 1990 S.C.S. PLASTICS PTY. LIMITED COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Hinge arrangementfor plastic container The following statement is a full description of this invention including the best method of performing it known to us:- 2 Technical Field Described embodiments generally relate to plastic containers and hinge arrangements therefor. 5 Background For some packaging, it is desirable to make it evident whether the packaging has been opened. For consumers purchasing the package, the evidence (or lack thereof) as to whether the package has been previously opened may affect the consumers' decision to purchase that package. Tamper-evident packaging is particularly relevant for consumer 10 products. Different methods have been attempted to make different packages tamper-evident. Some clear plastic thermoformed containers with a lid attached to a base by a hinge have previously used an added component, such as a label or adhesive tab, to provide 15 the tamper-evidence. Such a label or adhesive tab may be applied across adjacent portions of the lid and base so that the label or tab must be broken or removed in order to open the lid. However, such a tamper-evident feature requires that the label or tab be applied after the package has been filled and closed, which requires an extra production step and involves associated costs and problems. For example, for a fresh fruit product 20 that is filled into the container directly at the point of fruit harvesting, applying a label at that point would not be easy or efficient and would therefore add to cost. If the container requires a label to function as a tamper-evident seal and if it is not already applied at the point of harvest, then the container may have to be unpacked from distribution crates or boxes, the label applied and the containers then re-crated or boxed 25 for delivery to the point of sale or a further distribution point. Reliance on adhesive labels for tamper-evidence is also an added cost for packaging that does not otherwise require a label. 30 Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. 35 Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or 3 all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present disclosure as it existed before the priority date of each claim of this application. 5 Summary Some embodiments relate to a plastic thermoformed container, including: a base defining a support plane to support the container relative to another surface; a lid to close over the base; 10 a hinge integrally formed with the base and the lid, the hinge frangibly joining the lid and the base along a first line of perforation and a second line of weakness, the first and second lines extending a length of the hinge and defining a hinge intermediate portion, wherein the hinge intermediate portion comprises a tab projecting in a first direction generally perpendicular to the support plane when the lid is closed over the 15 base; wherein the tab is sized to readily allow it to be grasped and pulled to separate the lid from the base along at least the first line by pulling the tab in a second direction generally opposite to the first direction. 20 The first line may have at least one linear portion and at least one non-linear portion. The first line may have a linear portion extending on each lateral side of the tab. The tab may be cut from the material of the hinge adjacent an upper part of the base portion, leaving a recess in the hinge corresponding to a shape of the tab when the lid is closed over the base. 25 The hinge intermediate portion may comprise a second tab projecting in the first direction. Alternatively, the hinge intermediate portion may comprise a second tab projecting in the second direction. 30 The hinge intermediate portion has a first lateral length and the tab may have a second lateral length that is less than the first lateral length and does not extend laterally beyond either end of the hinge intermediate portion. The base defines a mouth at an upper part of the base, wherein the lid and base may 35 comprise mating snap-fitting structure to allow the lid to snugly fit into the mouth of the base, thereby defining an enclosed container volume. The lid may be free of 4 portions around its edge upon which finger purchase can be made when the lid is snugly fitted into the mouth. The second line of weakness may comprise perforations so that the hinge intermediate 5 portion can be torn from the container along the first and second lines, thereby allowing the lid to be separated from the base by pulling apart remainder portions of the hinge. When the lid is closed over the base, the hinge intermediate portion may extend in a plane generally perpendicular to the support plane. A lateral length of the tab may be at 10 least the lateral width of an average adult human forefinger. The lateral length of the tab may be at least the lateral width of two average adult human fingers or possibly four fingers. Some embodiments relate to a plastic thermoformed container, comprising: 15 a base defining a container volume and one or more container support surfaces defining a support plane at a base lower portion to support the container relative to another surface, the base further defining a mouth at a base upper portion; a lid to close over and fit into the mouth of the base, the lid being free of grippable portions around where the lid fits into the base that would allow the lid to be 20 manually pulled from the base; and a hinge disposed on one side of the base upper portion and integrally formed with the base and the lid, the hinge having a hinge base portion, a hinge lid portion and a hinge intermediate portion frangibly joining the hinge base portion and the hinge lid portion, wherein the hinge comprises a first line of weakness between the hinge lid 25 portion and the hinge intermediate portion and comprises a second line of weakness between the hinge base portion and the hinge intermediate portion, and wherein the hinge intermediate portion comprises a tab projecting in a first direction generally perpendicular to the support plane when the lid is closed over the base. 30 Some embodiments relate to a method of providing a plurality of containers, the method comprising: forming a plurality of the containers as described above; applying a label to each of the containers; nesting the plurality of labelled container together, the containers nested in an 35 open position; and 5 providing the nested containers for separation, filling and subsequent closure of the lid over the base. The label may be applied to the lid or to the base but not both. The forming may 5 comprise thermoforming the lid, base and hinge as a unitary structure and then partly cutting along the hinge to form at least the first line of perforation. Brief description of the drawings Embodiments are described in further detail below, by way of example, with reference 10 to the accompanying drawings, in which: Figure 1A is a plan view of a container with a hinge arrangement according to some embodiments, shown in an open position; 15 Figure lB is a side view of the container shown in Figure IA; Figure IC is one end view of the container shown in Figure IA; Figure 1 D is a top perspective view of the container shown in Figure 1 A; 20 Figure 2A is a bottom perspective view of the container shown in Figure IA, shown in a closed position; Figure 2B is a top perspective view of the container shown in Figure 2A; 25 Figure 2C is a plan view of the container shown in Figure 2A; Figure 3A is a sectional view of the container shown in Figure 2C, taken along line A A; 30 Figure 3B is a sectional view of the container shown in Figure 2C, taken along line C C; Figure 4 is a close-up view of part of the container shown in cross-section in Figure 35 3A; 6 Figure 5 is a close-up view of part of the container shown in cross-section in Figure 3B; Figure 6A is a perspective view of the closed container shown in Figures 2A to 2C, with part of the hinge in a state of partial removal; 5 Figure 6B is a perspective view similar to Figure 6A, but with the hinge part fully removed; Figure 6C is a perspective view of the container similar to Figures 6A and 6B, but with 10 the hinge part removed and the lid removed from the base; Figure 7A is a plan view of a container having a hinge arrangement according to further embodiments, shown in an open position; 15 Figure 7B is a top perspective view of the container shown in Figure 7A, shown in an open position; Figure 8A is a plan view of the container shown in Figure 7A, but shown in a closed position; 20 Figure 8B is a side view of the container shown in Figure 8A; Figure 8C is a further side view of the container shown in Figure 8A; and 25 Figure 8D is a top perspective view of the container shown in Figure 8A. Detailed description Described embodiments generally relate to plastic containers and hinge arrangements therefor. Described embodiments generally also relate to thermoformed packages with 30 a hinge joining a lid to a base along one side of the base. The lid, base and hinge may be integrally formed. The lid and base have co-operating snap fitting engagement portions that make it difficult to manually separate the lid from the base once the lid is closed in place over the base. Thus, according to described embodiments, it is via a tamper-evident frangible hinge that a consumer can gain purchase to pull the lid from 35 the base. Such frangible hinge arrangements are described in further detail below, with reference to Figures 1A to ID, 2A to 2C, 3A, 3B, 4, 5, 6A to 6C, 7A, 7B and 8A to 8D.

7 Referring firstly to Figures 1A to ID, 2A to 2C, 3A, 3B, 4, 5 and 6A to 6C, a container 100 having a hinge arrangement according to some embodiments is described. Container 100 has a base 110 and a lid 130 coupled to the base 110 by a hinge 150. The base 110 has an upper part 112 with rim structure 122 defining a mouth. Rim 5 structure 122 is continuous about the mouth but has some variation in form along a side edge where the hinge 150 extends. The material of the container 100 (and container 700 described below) is preferably of substantially uniform thickness and may be formed of suitable thermoformable plastics, such as clear, coloured or translucent plastics, that can hold a thermoformed shape once cooled. 10 Base 110 also has a lower part 114 and side walls 118 extending between the lower part 114 and the upper part 112. Side walls 118 are angled slightly outwardly from the lower part 114 to the upper part 112 to facilitate nesting of multiple containers 100. The lower part 114 has a base bottom surface that includes one or more support 15 surfaces 116 upon which the container 100 can be supported when it is placed on another surface, such as a flat and/or horizontal surface. The support surfaces 116 define a support plane at the parts of the bottom surface of base 110 where the support surfaces would contact a flat surface on which the container 100 can be rested. The bottom surface of base 110 need not be flat. Similarly, side walls 118 need not be flat 20 and both the side walls 118 and the bottom surface of base 110 may be formed with ribs, ridges and/or cut-outs, depending on the desired container configuration. While container 100 is shown as being generally rectangular in plan view, other shapes and configurations can be employed with the same or similar hinge arrangement as is 25 described herein. An example of an alternative circular shape and configuration of the container is shown and described below in relation to Figures 7A, 7B and 8A to 8D. Lid 130 has an outer rim 132 that is shaped with a complementary structure to engage with the rim structure 122 around the mouth of the base 110 to fit into and close over 30 the base 110, thereby enclosing a volume within the container 100. The lid 130 is free of any grippable portions or other parts upon which fingers could gain purchase (other than via the frangible hinge 150) when the lid 130 is closed over the base 110. Thus, a consumer wishing to open the container 100 would find it quite difficult to pry the lid 130 from the base 110 along sides of the container 100 other than where the hinge 150 35 extends, thus inducing the consumer to rip apart the frangible hinge 150 to open the container 100. Once the frangible hinge 150 is ripped, this provides evidence of the 8 container 100 having been opened. In combination with the sealing of the lid 130 around the mouth of the base 110, hinge 150 thus provides a tamper-evident closure. Described embodiments generally contemplate the container 100 being thermoformed 5 as a unitary structure, with the hinge subsequently being cut and/or creased in order to form at least one line 162 of perforation and a second line 164 of weakness. In some embodiments, second line 164 may be creased, pressed or perforated in a manner that readily allows folding along the second line 164 but that does not readily allow tearing along the second line 164. In other embodiments, the second line 164 may include 10 sufficient perforations to allow it to be readily ripped from the hinge 150 while also ripping along the first line 162. The perforations along the first line 162, and optionally also along the second line 164, may cut through about 70% to about 98% of the plastic material of the hinge along the respective lines, 162, 164, depending on the desired ease of frangibility of the hinge. 15 Hinge 150 comprises a hinge lid portion 154 that extends from and is continuous with the lid 130. Hinge 150 further comprises a hinge base portion 152 that extends from and is continuous with the base 110 along one side of its upper part 112. Hinge 150 further comprises an intermediate hinge portion 156 defined by the first and second 20 lines 162, 164 and extending therebetween. Intermediate hinge portion 156 includes a tab 165 that is cut from the material of the hinge base portion 152 so that, when the lid 130 is folded over and fitted into the mouth of the base 110, the hinge 150 folds at roughly 900 along the first and second lines 162, 164, with the tab 165 separating from the hinge base portion 152 and remaining in the same plane as the rest of the hinge 25 intermediate portion 156. In the open configuration of container 100 shown in Figures 1A to ID, the hinge base portion 152, hinge intermediate portion 156 and hinge lid portion 154 all lie in a common plane that is generally parallel to the support plane. However, when the lid 30 130 is folded over into the closed position, the hinge lid portion 154 (having folded about 1800) generally overlies the hinge base portion 152 and the intermediate hinge portion 156, having folded roughly 90' relative to each of the adjacent base and lid hinge portions 152, 154, lies in a plane generally perpendicular to the support plane. 35 It should be understood that "perpendicular" in the sense used herein need not be exactly perpendicular and that some reasonable angular variation may be tolerated, for 9 example up to a few tens of degrees. It should also be understood that for thermoformed plastics material, a relatively large margin of bending variation can be tolerated while nevertheless achieving the desired function. For example, where a 900 bend or relative angle is described herein, a variation in the order of several tens of 5 degrees may be tolerated without affecting the function of the parts under consideration. Tab 165 has a lateral length that is less than the total lateral length of the hinge intermediate portion 156. The tab 165 may be positioned to one lateral side of the 10 hinge 150, as shown in Figure 1A, or centrally, as shown in Figure 7A. The tab 165 is positioned to be laterally interior of the opposed lateral ends of hinge intermediate portion 156, leaving straight (optionally co-axial) frangible portions along the first line 162 of perforation to each lateral side of the tab 165. 15 The tab 165 may project in a direction generally perpendicular to the support plane to an extent that is greater than the height of the intermediate hinge portion 156 along parts of its length from which tab 165 does not project. Thus, tab 165 may have a height or depth that is, say 2 to 5 times the height or depth of the hinge intermediate portion 156 along the rest of its length. This effective greater size of the tab 165 is 20 intended to allow for easier grasping and pulling of the tab 165 in order to rip the intermediate hinge portion 156 along at least the first line 162 and, depending on the embodiment, possibly also along the second line 164. In some embodiments, more than one tab 165 may be formed on the intermediate hinge 25 portion 156, either projecting in the same direction or in opposite directions. For a further tab that extends in the opposite direction to the first tab 165, it may be used to tear off the hinge intermediate portion 156 by pulling generally downwardly in the direction of the support plane. Alternatively, although the tab 165 is shown in the Figures as projecting generally toward the support plane, other embodiments may have 30 the tab 165 extend in the opposite direction, that is, upwardly away from the support plane, while remaining frangible in the manner described herein. The lateral length of the tab 165 may be in the order of about 20 to 80% of the total lateral length of the intermediate hinge portion 156, for example. The lateral length of 35 the tab 165 may also be expressed in terms of the lateral width of the average adult human finger, such as the forefinger, for example. In this regard, the tab 165 is at least 10 the lateral width of the average human forefinger and may be at least two finger widths or may be sized to accommodate all four fingers (other than the thumb) in order to readily allow the consumer to insert their fingers under the tab 165 and pull upwardly (generally in a direction opposite to the direction in which the tab 165 projects). 5 As shown in Figure 2A, a recess 166 is formed in the base hinge portion 152 where the tab 165 has been cut out and when the lid 130 is in the closed position. This recess 166 aids a consumer in fitting their fingers into the hinge behind the tab 165 for greater ease of gripping and pulling on the tab 165 to separate the hinge intermediate portion 156 10 from the hinge base portion 152 and optionally also the hinge lid portion 154. Figures 6A, 6B and 6C illustrate removal of the hinge intermediate portion 156 by pulling on the tab 165, where the second line 164 is also a line of perforation. The remaining parts of hinge lid portion 153 and hinge base portion 152 can then be gripped 15 and pulled apart (in opposite directions) in order to remove the lid 130 from the base 110, as shown in Figure 6C. Conveniently, the lid 130 can be replaced and fitted back into the mouth of the base 110 in order to again close the container 100. However, it will be visually apparent that the container 100 has already been opened by the absence of the hinge intermediate portion 156 along hinge 150 (which will no longer function as 20 a hinge). The tab 165 may have indicia 167 thereon to indicate that it should be pulled in order to open the container 100. The indicia 167 may include directional arrows and/or text, such as the words "Pull to Open", for example. 25 The container 100 may comprise a label (not shown) which may be affixed to the lid 130 so that the label is displayed when the container is closed. Alternatively, the label may be affixed to another part of the container 100, such as along one or more of the side walls 118 or a bottom surface of the base 110. This label can be conveniently and 30 cost-effectively affixed immediately following manufacture (i.e. forming and cutting) of the container 100 since it does not need to be applied after the container is closed in order to provide the tamper-evident feature. The containers 100 can then be easily stacked and nested together in the open position to be transported to a filling site for subsequent separation, filling and closing. 35 11 The lid and base rim structures 132, 122, respectively, are illustrated in further detail in Figures 3A, 3B, 4 and 5. In particular, Figure 5 shows in cross-section the rim structure 122 being arranged to matingly receive part of the rim 132 of lid 130. Rim 132 has oscillating deformations formed therein, ending with an outer edge 134. The 5 rim structure 122 of the base 110 has a stepped profile to receive parts of the oscillating rim 132 and defines a slight overhang 124 to receive the outer edge 134 and obscure it from manual access, so that a consumer cannot gain purchase on the edge 134 and therefore cannot pry the lid 130 from the base 110 other than by breaking the hinge 150, as described above. 10 Referring also now to Figures 7A, 7B and 8A to 8D, a container 700 according to further embodiments is shown and described. Container 700 employs a similar hinge arrangement 750 to the hinge 150 described above, but is in the form of a generally circular container. 15 Container 700 has a base 710 and a lid 730 coupled to the base 170 by a hinge 750. The base 710 has an upper part 712 with rim structure 722 defining a mouth. Rim structure 722 is continuous about the mouth but has some variation in form along a part-circumferential side edge where the hinge 750 extends. 20 Base 710 also has a lower part 714 and side walls 718 extending between the lower part 714 and the upper part 712. Side walls 718 are angled slightly outwardly from lower part 714 to upper part 712 to facilitate nesting of multiple containers 700. The lower part 714 has a base bottom surface that includes one or more support surfaces 716 upon 25 which the container 700 can be supported when it is placed on another surface, such as a flat and/or horizontal surface. The support surfaces 716 define a support plane at the parts of the bottom surface of base 710 where the support surfaces would contact a flat surface on which the container 700 can be rested. The bottom surface of base 710 need not be flat. Similarly, side walls 718 need not be flat and both the side walls 718 and 30 the bottom surface of base 710 may be formed with ribs, ridges and/or cut-outs, depending on the desired container configuration. Lid 730 has an outer rim 732 that is shaped with a complementary structure to engage with the rim structure 722 around the mouth of the base 710 to fit into and close over 35 the base 110, thereby enclosing a volume within the container 700. The lid 730 is free of any grippable portions or other parts upon which fingers could gain purchase (other 12 than via the frangible hinge 750) when the lid 730 is closed over the base 710. Thus, a consumer wishing to open the container 700 would find it quite difficult to pry the lid 730 from the base 710 along sides of the container 700 other than where the hinge 750 extends, thus inducing the consumer to rip apart the frangible hinge 750 to open the 5 container 700. Once the frangible hinge 750 is ripped, this provides evidence of the container 700 having been opened. In combination with the sealing of the lid 730 around the mouth of the base 710, hinge 750 thus provides a tamper-evident closure. Described embodiments generally contemplate the container 700 being thermoformed 10 as a unitary structure, with the hinge subsequently being cut and/or creased in order to form at least one line 762 of perforation and a second line 764 of weakness. In some embodiments, second line 764 may be creased, pressed or perforated in a manner that readily allows folding along the second line 764 but that does not readily allow tearing along the second line 764. In other embodiments, the second line 764 may include 15 sufficient perforations to allow it to be readily ripped from the hinge 750 while also ripping along the first line 762. The perforations along the first line 762, and optionally also along the second line 764, may cut through about 70% to about 98% of the plastic material of the hinge along the respective lines, 762, 764, depending on the desired ease of frangibility of the hinge. 20 Hinge 750 comprises a hinge lid portion 754 that extends from and is continuous with the lid 730. Hinge 750 further comprises a hinge base portion 752 that extends from and is continuous with the base 710 along one side of the base upper part 712. Hinge 750 further comprises an intermediate hinge portion 756 defined by the first and second 25 lines 762, 764 and extending therebetween. Intermediate hinge portion 756 includes a tab 765 that is cut from the material of the hinge base portion 752 so that, when the lid 730 is folded over and fitted into the mouth of the base 710, the hinge 750 folds at roughly 900 along the first and second lines 762, 764, with the tab 765 separating from the hinge base portion 752 and remaining in the same plane as the rest of the hinge 30 intermediate portion 756. In the open configuration of container 700 shown in Figures 1A to ID, the hinge base portion 752, hinge intermediate portion 756 and hinge lid portion 754 all lie in a common plane that is generally parallel to the support plane. However, when the lid 35 730 is folded over into the closed position, the hinge lid portion 754 (having folded about 1800) generally overlies the hinge base portion 752 and the intermediate hinge 13 portion 756, having folded roughly 900 relative to each of the adjacent base and lid hinge portions 752, 754, lies in a plane generally perpendicular to the support plane. Tab 765 has a lateral length that is less than the total lateral length of the hinge 5 intermediate portion 756. The tab 765 may be positioned centrally along the hinge 150, as shown in Figure 7A. The tab 765 is positioned to be laterally interior of the opposed lateral ends of hinge intermediate portion 756, leaving straight (optionally co-axial) frangible portions along the first line 762 of perforation to each lateral side of the tab 765. The first line 762 of perforation is non-linear along part of its length to define the 10 tab 765 but is linear on either side of the tab 765. The tab 765 shown in Figures 7A and 7B has a curved edge along its length but may in other embodiments have at least some straight edge sections. As shown in Figures 7A and 7B, the hinge intermediate portion 756 may be formed 15 (during the forming step or during subsequent cutting) to have a lateral length that is less than the lateral length of the hinge base portion 752 and the hinge lid portion 754. This may assist with ease of tearing the hinge intermediate portion partially or fully free from the remainder of the hinge 750. 20 The tab 765 may project in a direction generally perpendicular to the support plane to an extent that is greater than the height of the intermediate hinge portion 756 along parts of its length from which tab 765 does not project. Thus, tab 765 may have a height or depth that is, say, 2 to 5 times the height or depth of the hinge intermediate portion 756 along the rest of its length. This effective greater size of the tab 765 is 25 intended to allow for easier grasping and pulling of the tab 765 in order to rip the intermediate hinge portion 756 along at least the first line 762 and, depending on the embodiment, possibly also along the second line 764. In some embodiments, more than one tab 765 may be formed on the intermediate hinge 30 portion 756, either projecting in the same direction or in opposite directions. For a further tab that extends in the opposite direction to the first tab 765, it may be used to tear off the hinge intermediate portion 756 by pulling generally downwardly in the direction of the support plane. Alternatively, although the tab 765 is shown in the Figures as projecting generally toward the support plane, other embodiments may have 35 the tab 765 extend in the opposite direction, that is, upwardly away from the support plane, while remaining frangible in the manner described herein.

14 The lateral length of the tab 765 may be in the order of about 20 to 80% of the total lateral length of the intermediate hinge portion 756, for example. The lateral length of the tab 765 may also be expressed in terms of the lateral width of the average adult human finger, such as the forefinger, for example. In this regard, the tab 765 is at least 5 the lateral width of the average human forefinger and may be at least two finger widths or may be sized to accommodate all four fingers (other than the thumb) in order to readily allow the consumer to insert their fingers under the tab 765 and pull upwardly (generally in a direction opposite to the direction in which the tab 765 projects). 10 As shown in Figure 8C, a recess 766 is formed in the base hinge portion 752 where the tab 765 has been cut out and when the lid 730 is in the closed position. This recess 766 aids a consumer in fitting their fingers into the hinge behind the tab 765 for greater ease of gripping and pulling on the tab 765 to separate the hinge intermediate portion 756 from the hinge base portion 752 and optionally also the hinge lid portion 754. The tab 15 765 may have indicia 767 thereon to indicate that it should be pulled in order to open the container 700. The indicia 767 may include directional arrows and/or text, such as the words "Pull to Open", for example. The container 700 may comprise a label (not shown) which may be affixed to the lid 20 730 so that the label is displayed when the container is closed. Alternatively, the label may be affixed to another part of the container 700, such as along one or more of the side walls 718 or a bottom surface of the base 710. This label can be conveniently and cost-effectively affixed immediately following manufacture (i.e. forming and cutting) of the container 700 since it does not need to be applied after the container is closed in 25 order to provide the tamper-evident feature. The containers 700 can then be easily stacked and nested together in the open position to be transported to a filling site for subsequent separation, filling and closing. The embodiments and examples set forth herein are provided for illustrative purposes 30 and are not intended to limit the operation or application of the invention. Various modifications or enhancements of the described embodiments may be made while remaining within the spirit of the invention. This description should therefore not be construed in a narrowing or limiting fashion.

Claims (16)

1. A plastic thermoformed container, including: a base defining a support plane to support the container relative to another surface; 5 a lid to close over the base; a hinge integrally formed with the base and the lid, the hinge frangibly joining the lid and the base along a first line of perforation and a second line of weakness, the first and second lines extending a length of the hinge and defining a hinge intermediate portion, wherein the hinge intermediate portion comprises a tab projecting in a first 10 direction generally perpendicular to the support plane when the lid is closed over the base; wherein the tab is sized to readily allow it to be grasped and pulled to separate the lid from the base along at least the first line by pulling the tab in a second direction generally opposite to the first direction. 15

2. The container of claim 1, wherein the first line has at least one linear portion and at least one non-linear portion.

3. The container of claim 2, wherein the first line has a linear portion extending on 20 each lateral side of the tab.

4. The container of any one of claims 1 to 3, wherein the tab is cut from the material of the hinge adjacent an upper part of the base portion, leaving a recess in the hinge corresponding to a shape of the tab when the lid is closed over the base. 25

5. The container of any one of claims 1 to 4, wherein the tab is a first tab and the hinge intermediate portion comprises a second tab projecting in the first direction.

6. The container of any one of claims 1 to 4, wherein the tab is a first tab and the 30 hinge intermediate portion comprises a second tab projecting in the second direction.

7. The container of any one of claims 1 to 6, wherein the hinge intermediate portion has a first lateral length and the tab has a second lateral length that is less than the first lateral length and does not extend laterally beyond either end of the hinge 35 intermediate portion. 16

8. The container of any one of claims 1 to 7, wherein the base defines a mouth at an upper part of the base, wherein the lid and base comprise mating snap-fitting structure to allow the lid to snugly fit into the mouth of the base, thereby defining an enclosed container volume, and wherein the lid is free of portions around its edge upon 5 which finger purchase can be made when the lid is snugly fitted into the mouth.

9. The container of any one of claims 1 to 8, wherein the second line of weakness comprises perforations so that the hinge intermediate portion can be torn from the container along the first and second lines, thereby allowing the lid to be separated from 10 the base by pulling apart remainder portions of the hinge.

10. The container of any one of claims 1 to 9, wherein, when the lid is closed over the base, the hinge intermediate portion extends in a plane generally perpendicular to the support plane. 15

11. The container of any one of claims 1 to 10, wherein a lateral length of the tab is at least the lateral width of an average adult human forefinger.

12. The container of claim 11, wherein the lateral length of the tab is at least the 20 lateral width of two average adult human fingers.

13. A plastic thermoformed container, comprising: a base defining a container volume and one or more container support surfaces defining a support plane at a base lower portion to support the container relative to 25 another surface, the base further defining a mouth at a base upper portion; a lid to close over and fit into the mouth of the base, the lid being free of grippable portions around where the lid fits into the base that would allow the lid to be manually pulled from the base; and a hinge disposed on one side of the base upper portion and integrally formed 30 with the base and the lid, the hinge having a hinge base portion, a hinge lid portion and a hinge intermediate portion frangibly joining the hinge base portion and the hinge lid portion, wherein the hinge comprises a first line of weakness between the hinge lid portion and the hinge intermediate portion and comprises a second line of weakness between the hinge base portion and the hinge intermediate portion, and wherein the 35 hinge intermediate portion comprises a tab projecting in a first direction generally perpendicular to the support plane when the lid is closed over the base. 17

14. A method of providing a plurality of containers, the method comprising: forming a plurality of the container of any one of claims 1 to 13; applying a label to each of the containers; nesting the plurality of labelled container together, the containers nested in an 5 open position; and providing the nested containers for separation, filling and subsequent closure of the lid over the base.

15. The method of claim 14, wherein the label is applied to the lid or to the base but 10 not both.

16. The method of claim 14 or claim 15, wherein the forming comprises thermoforming the lid, base and hinge as a unitary structure and then partly cutting along the hinge to form at least the first line of perforation. 15