US20060163265A1 - Hook style tamper evident lid - Google Patents

Abstract

A tamper evident lid is provided for mounting over an opening of a container having sidewalls with a lip extending outwardly therefrom to define the opening. The lid has a base, a rim extending about a perimeter of the base for receiving the lip and at least one finger extending upwardly from the rim and toward the base for engaging an underside of the lip. A frangible membrane is associated with the fingers to facilitate outward tearing of the finger regions away from the sidewalls. Each finger has a length exceeding the distance between an inside of the lip and the sidewall.

Description

• This application is a continuation-in-part of International Application No. PCT/CA03/00055, filed Jan. 17, 2003, and also a continuation-in-part of International Application No. PCT/CA02/01311, filed on Aug. 26, 2002, and also claims the benefit of U.S. Provisional Application No. 60/399,731, filed Aug. 1, 2002.
FIELD OF THE INVENTION
• This invention relates generally to injection moulded containers and their lids. More specifically this invention relates to tamper evident lids which may be applied to standard containers.
BACKGROUND OF THE INVENTION
• Tamper evident (TE) features are very important in the packaging industry. Unfortunately, packages having tamper evident features generally require specific container and lid designs making the container and the lid a unique combination. A disadvantage to this type of design is that expensive moulds are required not only for the container but for the lid and the moulds are often limited in design to a single product.
• Many applications in the food packaging industry currently use “standard” container sizes, which can be purchased from a multitude of suppliers. The containers are generally filled with packaging machinery adapted to those container sizes. If special containers and lids are to be used, it may be necessary to install additional machinery in a filling line to accommodate assembly limitations caused by the special tamper evident containers.
• U.S. Pat. No. 5,540,342 by Rathbun describes a lid having a dual locking system to retain the lid on a container. The lid uses a purality of primary beads and secondary locking ribs to retain the lid on the container.
• However, one disadvantage of Rathbun's lid is that the locking ribs are completely removed from the lid once the lid is initially from the container, thus removing all visual evidence of the released locking ribs.
• It is an object of the present invention to provide a tamper evident lid which may be used with a standard container. Preferably the lid may be mounted onto such a container using conventional packaging equipment currently available in most automated filling lines.
SUMMARY OF THE INVENTION
• A tamper evident lid is provided for mounting over an opening of a container having sidewalls with a lip extending outwardly therefrom to define an opening. The lid has a base, a rim extending about the base for receiving the lip and at least one resiliently flexible finger extending radially inwardly from the rim for engaging the lip. Each finger has a length exceeding the distance between an inside of the lip and the sidewall and extends towards the base when the lid is mounted on the container. At least one frangible membrane is formed in the rim and associated with at least one of the fingers for facilitating tearing of the rim to disengage the associated finger(s) from the lip thereby enabling removal of the lid from the container while leaving evidence of removal by way of a torn frangible membrane.
• The rim may have an upper end adjacent the base and a lower edge distal the base with the frangible membrane extending from the lower edge toward the upper end.
• A respective of the frangible membranes may be disposed on opposite sides of at least one finger. Alternatively, at least one pair of fingers may be provided with each one of the pair of fingers disposed on an opposite side of the frangible membrane.
• The frangible membrane may extend to a membrane hinge formed in at least one of the rim and the base. The membrane hinge may be positioned to facilitate disengagement of the associated finger from the lip upon tearing of the frangible membrane.
• The associated finger may be disposed between the membrane hinge and the lower edge.
• The frangible membrane may extend to at least one membrane hinge formed in the rim. Each such membrane hinge may extend from the lower edge toward the base with an associated finger disposed in any area bordered by the frangible membrane, a membrane hinge and a lower edge.
• A pair of fingers may be disposed between a pair of membrane hinges extending from the lower edge toward the base. A frangible membrane may extend from the lower edge to each one of the pair of the membrane hinges so that each of the fingers is disposed in an area bordered by at least part of the frangible membrane, one of the membrane hinges and the lower edge.
• A pair of radially spaced apart frangible membranes may be provided with at least one of the resilient fingers disposed therebetween. A membrane hinge may extend across the base between the frangible membranes to facilitate disengagement of the fingers from the lip upon tearing of the frangible membranes by bending a portion of the base away from the lip.
• A plurality of fingers may be disposed between the frangible membranes of the embodiment described in the preceding paragraph.
• At least one of the fingers may be a webbed finger having a web defined by a reduced thickness region extending toward the rim from a lip engaging end of the webbed finger which is distal the rim.
• Each webbed finger may be provided with a passage therethrough in the form of a window to promote drainage of fluid trapped between the webbed finger and the rim.
• The fingers may be of various profiles including rounded, parallel faced straight, tapered narrowing toward the rim and tapered narrowing toward the rim with a scallop facing the container at an outer end thereof distal the rim.
• Each finger may be curved in a direction generally corresponding to a curvature of the container to provide a lengthened contact zone with the lip.
• The rim may be a recess extending from the fingers to the lower edge to accommodate the fingers thereby facilitating stripping of the lid in an injection moulding process.
• The fingers may extend from the lower edge of the rim.
• At least one pull tab may extend from the lower edge of the rim to facilitate tearing of at least one of the frangible membranes.
• A stacking ring may extend about the base away from the rim to engage the lower edge of an adjacent tamper evident lid when the lids are stacked in order to resist lateral shifting therebetween. The stacking ring may be segmented or continuous.
• A chamfer may extend into the rim from the lower edge at the juncture of the frangible membranes and the lower edge to avoid a sharp corner at the juncture upon tearing of the frangible membrane.
BRIEF DESCRIPTION OF THE DRAWINGS
• Preferred embodiments of the present invention are described below with reference to the accompanying illustrations in which:
• FIG. 1 is a perspective view from below of a tamper evident lid according to the present invention;
• FIG. 2 is a perspective view from above of the lid ofFIG. 1;
• FIG. 3A is a perspective sectional view taken at line3-3 ofFIG. 1;
• FIG. 3B is a view corresponding toFIG. 3A but taken from the inside rather than from the outside of the lid;
• FIG. 4 is a perspective sectional view taken on line4-4 ofFIG. 1;
• FIG. 5 is an axial section of an outer portion of a lid according to the present invention illustrating how it mounts over a container;
• FIG. 6 is an axial sectional view of a lid according to the present invention being moulded and illustrating the associated mould components;
• FIG. 7 is a schematic view of an injection moulding arrangement for forming a lid according to the present invention;
• FIG. 8 is a perspective view from below illustrating an alternate embodiment for a temper evident lid according to the present invention;
• FIGS. 8aand8bare scrap perspective views illustrating alternate features associated with theFIG. 8 embodiment;
• FIG. 9 is a sectional perspective view illustrating a further alternate embodiment for a tamper evident lid according to the present invention;
• FIG. 10ais a perspective view from above illustrating a still further embodiment for a tamper evident lid according to the present invention;
• FIG. 10bis a perspective from below of theFIG. 10aembodiment;
• FIGS. 11 and 11aillustrate alternate embodiments for a “finger” portion illustrating a tamper evident lid according to the present invention;
• FIGS. 12 and 12aare respectively scrap perspective views from below and above illustrating a “pull tab” feature of a tamper evident lid according to the present invention;
• FIGS. 13a,13b,13cand13dare scrap perspective views illustrating further alternate embodiments for a “finger” portion of a tamper evident lid according to the present invention;
• FIG. 14 is a scrap perspective view illustrating a still further alternate embodiment for a “finger” portion of a tamper evident lid according to the present invention;
• FIG. 15 is a scrap perspective view illustrating an embodiment of a tamper evident lid according to the present invention wherein a “finger” portion extends from a lower edge thereof;
• FIG. 16 is a perspective view from above illustrating yet another alternate embodiment for a tamper evident lid according to the present invention;
• FIG. 17 is a perspective view from above illustrating the use of chamfered edges as a safety feature associated with “tab” portions of a tamper evident lid according to the present invention;
• FIG. 18 is a perspective bottom view of a further embodiment of the lid ofFIG. 1;
• FIG. 19 is an enlarged view of an operated tab portion of the lid ofFIG. 18;
• FIG. 20 is a side sectional view taken on the line5-5 ofFIG. 18;
• FIG. 21 is a perspective bottom view of an alternative embodiment of the lid ofFIG. 18;
• FIG. 22 is a side sectional view taken on line6-6 ofFIG. 21; and
• FIG. 23 is a top view of an alternative embodiment of the lid ofFIG. 18.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
• A tamper evident lid (“lid”) according to the present invention is generally illustrated byreference10 in the accompanying illustrations. Thelid10 has abase12 and arim14 which extends about the perimeter of thebase12.
• Discrete fingers20 extend from an inside of therim14. The fingers extend radially inwardly and toward the base12 (inwardly and upwardly as illustrated in the figures).
• Thelid10 is intended for mounting over a “standard container”13 as illustrated inFIG. 5. A portion of a sidewall of such acontainer13 is shown in dashed lines atreference30. As typical withsuch containers13 which are commonly used for food and other applications, thesidewall30 terminates in an outwardly and downwardly extendinglip32. Thelip32 defines anopening34 over which thelid10 may be mounted.
• Each of thefingers20 has a length which exceeds the distance or “gap” between the inside of therim14 and the outside of thesidewall30 as illustrated at reference41. The length of thefingers20 exceeds the breadth of the gap as illustrated byarrow44. Accordingly, when thelid10 is forced over thelip32, thefingers20 flex toward a retracted position against the inside of therim14. Once fully past thelip32, the fingers flex inwardly, away from therim14, to rest against thesidewall30. The direction of this spring bias is indicated byreference31. In order to enable the flexing of thefingers20, the material of thelid10 must have a desired degree of resiliency which is characteristic of the type of plastics typically used for such lids (polyethylene for example). Basically thefingers20 must be able to flex without breaking off.
• Once in place, removal of thelid10 from thecontainer13 is resisted by thefingers20 engaging anunderside36 of thelip32. As the ends offingers20 rest against thesidewall30, thefingers20 can rely on thesidewall30 for support and accordingly a tremendous amount of strength is not required from thefingers20. This proves advantageous in stripping thelid20 from an injection moulding assembly, as discussed below.
• To either side of thefingers20 is a frangible membrane22 (seeFIG. 1) formed in therim14 to define “tear tabs”24. Thetear tabs24 may be pried away from thesidewall30 by tearing thefrangible membranes22 to either side to move thefingers20 out of engagement and away from thelip32. This enables removal of thelid10 from thecontainer13 but only by leaving evidence in the form of tornfrangible membranes22.
• A membrane hinge26 (seeFIG. 3a) may be provided at the top of thetear tabs24 to maintain thetear tabs24 affixed to the remainder of thelid10 after tearing of thefrangible membranes22. This avoids having to tear thetear tabs24 out entirely in order for thefingers20 to be disengaged from thelip32. Without thehinge26, the resiliency of thelid10 might otherwise keep urging thefingers20 into engagement with thelip32 even with thefrangible membranes22 torn.
• Alternatively themembrane hinge26 may be substituted for a furtherfrangible membrane22 to allow complete removal of thetear tabs24.
• An inwardly extending rib50 (seeFIG. 1) may be provided about therim14 of thelid10 between thebreak tabs24. Theribs50 serve to further secure thelid10 over theopening34 by engagement with the lip32 (seeFIG. 5).
• Preferably therim14 at thetear tabs24 is thinner below the finger20 (distal the base12) than above the finger20 (proximal the base12) by an amount corresponding to the thickness of thefingers20. This forms a recess28 (seeFIG. 3b) which accommodates thefingers20 during a stripping stage of thelid10 in an injection moulding operation.
• FIGS. 6 and 7 illustrate a mould assembly for plastic injection moulding of thelid10. The mould assembly includes acavity100 which receives a two-part mould core made up of a removingcore poppet102 and acore base104. Astripper ring110 extends about thecore base104 to engage alower edge18 of therim14 of thelid10. Thecavity100 and movingcore poppet102 are movable in opposite relative directions as are thecore base104 and movingcore poppet102.
• After injection and solidification of a molten resin to form thelid10, the formedlid10 will typically shrink onto the movingcore poppet102 andcore base104 enabling thelid10 in combination with thecore poppet102 andcore base104 andstripper ring110 to be moved away from thecavity100 as the mould is opened. Next, thecore poppet102,stripper ring110 andlid10 move away from thecore base104 toward thecavity100. Thecore poppet102 stops moving and thestripper ring110 pushes thelid10 off of thepoppet102.
• As shown by dashed lines inFIG. 6, thefinger20 flexes away from thebase12 of thelid10 and is accommodated by therecess28 as thelid10 is lifted off of the movingcore poppet102.
• Thefingers20 will generally retain enough “memory” to resiliently flex toward their original position as the formedlid10 cools after stripping.
• Alternatively thefingers20 may be configured to cool so as to point away from the base12 (“down”) and be pushed into an “upwards” position mechanically after moulding.
• Although sixtear tabs24 are illustrated, other numbers are possible. Generally it is expected that six to eight will prove an optimal compromise between security and effort to remove thelid10. It may be possible to have as few as onetear tab24 if it is broad enough to retain thelid10 on thecontainer13. Two or more is preferable. It is generally not necessary to lift away all of thetear tabs24 for removal of thelid10. Lifting away thetear tabs24 about half the perimeter and sometimes less of thelid10 will generally prove sufficient to enable removal of thelid10 when installed on thecontainer13.
• As illustrated inFIG. 8 it isn't necessary to provide afrangible membrane22 on opposite sides of thefingers20. For example, more than onefinger20 may be provided between adjacent of thefrangible membranes22. Alternatively, as illustrated inFIG. 8a, a singlefrangible membrane22 may be provided adjacent thefinger20. Whether the latter arrangement is truly effective will depend on the overall configuration of thelid10 and howmany fingers20 have to be displaced in order to release thelid10. This arrangement may be less practical whenseveral fingers20 are used unless thefrangible membrane22 extends from a lower edge29 (seeFIG. 11) of therim14 about thefinger20 to amembrane hinge26 on an opposite side of thefinger20 as illustrated inFIG. 8b.
• In some instances it may be desirable to avoid the use of amembrane hinge26 or to provide one with significant restorative force characteristics. This might for example be the case where it is desired for thefingers20 to participate in “locking” thelid10 to thecontainer lip32 upon reapplication of thelid10. Such an arrangement is illustrated inFIG. 9.
• As illustrated inFIGS. 10aand10b, themembrane hinge26 may extend across the base12 between twofrangible membranes22. This provides good opening characteristics and is particularly useful for spices and other pourable products.
• FIGS. 11 and 11aillustratefingers20 of considerably more span than in many of the other illustrations. In order to achieve such a span without interfering with flexing of thefingers20 toward thebase12 and to maintain engagement between alip engaging end21 of thefingers20 distal therim14,webs23 are provided. Thewebs23 represent a thinner area (i.e. a reduced thickness region) extending toward therim14 from thelip engaging end21. Thewebs23 enable thefinger20 to flex in a manner similar to a row of closely spacedindividual fingers20 of lesser span in side by side juxtaposition.
• Thewider span fingers20 of theFIGS. 11 and 11aembodiment may be more prone to retaining moisture between thefingers20 and therim12. Accordingly passages or holes in the form ofwindows25 may be provided through thefingers20 as shown inFIG. 11a. Thewindows25 are illustrated as being rectangular however any configuration may be used including circular and triangular and combinations of the foregoing.
• As illustrated inFIGS. 12 and 12a, one ormore pull tabs40 may be provided extending from therim14 of thelid10 away from thebase12. Thepull tabs40 assist in tearing of thefrangible membranes22 by providing an enhanced gripping surface for digital grasping. Preferably thepull tabs40 should bend radially outwardly somewhat to assist in stacking of thelids10.
• A variety of configurations for thefingers20 may be utilized.FIGS. 13athrough13dillustrated a few representative examples.FIG. 13aillustrates a rounded configuration.FIG. 13billustrates a straight parallel faced configuration.FIG. 13cillustrates a tapered configuration narrowing toward therim14.FIG. 13dillustrates a configuration similar to that ofFIG. 13cbut further having ascallop42 for facing the container extending into itslip engaging end21.
• FIG. 14 illustrates afinger20 which is curved facing the container in a direction generally corresponding to a curvature of the container. This provides a longer contact zone along thelip engaging end21 than would be possible with astraight finger20. Astraight finger20 would have a tendency of only engaging thelip22 along part of the length of thelip engaging end21.
• FIG. 15 illustrates a portion of arim14 having afinger20 extending from itslower edge29 thereby eliminating a “foot”portion44 of therim14 which extends between thelower edge29 and thefinger20 in the other illustrations. Such an arrangement is possible but wouldn't stack as well as thelids10 having afoot portion44 and would therefore apply more to large industrial containers than stackable filling lines.
• Referring toFIG. 16, to promote stacking a stackingring46 may be provided extending about the base12 in a direction opposite to that of therim14. The stackingring46 engages thefoot portion44 of anunderlying lid10 to resist lateral shifting therebetween. The stackingring46 may be segmented as illustrated inFIG. 2 or continuous as illustrated inFIG. 16.
• A continuous stackingring46 can be easier to manufacture. To provide a continuous stackingring46 themembrane hinge26 may be located on therim14 below thebase12.FIG. 16 shows two possible arrangements. In the first such arrangement themembrane hinge26 is to the right of atab24 and afrangible membrane22 extends from thelower edge29 about the finger (not illustrated) to thefrangible membrane26. The finger would extend radially inwardly from thetab24.
• Alternatively, as shown toward the right ofFIG. 16, thetab24 may be defined by amembrane hinge26 between thelower edge29 and thebase12 and afrangible membrane22 to either side thereof. Thefrangible membranes22 extend from thelower edge29 to themembrane hinge26.
• As a safety precaution it is desirable to avoid sharp edges upon tearing of thefrangible membranes22. One way of achieving this, as illustrated inFIG. 17, is to provide achamfer52 extending into therim14 from itslower edge29 at the juncture of thefrangible membrane22 and thelower edge29. The chamfer will avoid a sharp point in the tornfrangible membrane22. Different arrangements of themembrane hinge26 and thefrangible membranes22 are illustrated inFIG. 17 in association with thechamfer52.
• Referring toFIG. 18, an alternative embodiment of thelid10 has therim14 extending around the periphery of thebase12 and depending from the base12 to thelower edge29. A series of thetabs24 are located at spaced locations around therim14 for indicating the sealing state of thelid10 when mounted on the container13 (seeFIG. 5), i.e. either previously opened or unopened. Thetabs24 have adjacentfrangible membranes22, situated adjacent to each of thefingers20, between amain sidewall25 of therim14 and thetabs24. Thefrangible membranes22 extend between thelower edge29 of therim14 and thebase12. The inwardly extending ribs or undercuts50 have extendingportions60 that extend past themembranes22 and overlap onto the underside of thetabs24, while leaving sufficient spacing for thefingers20 as an interruptedportion62 between adjacent ones of the extendingportions60. The interruptedportions62 allow thefingers20 to flex outwardly towards the retracted position against the inside of therim14. It is noted that thetabs24 have afirst tab portion24aincluding the overlapped extendingportions60, and asecond tab portion24bpositioned between thefirst tab portion24aand thelower edge29 of therim14. Further, thelid10 can also havevertical ribs74 positioned on thefirst tab portion24ato help alleviate bounce on the spin bars (not shown) during manufacture of thelid10.
• Referring toFIG. 19, in operation of thelid10, the extendingportions60 interrupt the tearing of thefrangible membranes22, such that thesecond tab portion24bseparates from themain sidewall25 of therim14, while thefirst tab portion24aremains attached thereto. The extendingportions60 of therib50 provide tear resistance of themembranes22, such that only part of themembranes22 tears adjacent to thesecond tab portion24b. This partial tearing of themembrane22 helps to maintain the integrity of therim14 between theribs50 and thebase12, such that thelid10 once opened can be resealed onto the container13 (seeFIG. 5).
• Referring toFIG. 20, it can be seen that thefirst tab portion24ais thinner in cross section than that of thesecond tab portion24b, thereby defining an offset sidewall that provides an offsethinge64. It is recognised that positioning of the offsethinge64 between theportions24aand24bhelps to promote bending of thetab portion24bto one side of the extendingportions60, providing a means for thefinger20 of thetab portion24bto remain positioned away (see ghosted view) from thesidewall30 of the container13 (seeFIG. 5) once themembranes22 are partially broken during opening of thelid10. Further, it can be seen that alocal pocket66 is provided by thefirst tab portion24abetween adjacent sections of the sidewall25 (seeFIG. 19).
• Referring toFIGS. 6 and 20, it is recognised that forming thefrangible membranes22 from thelower edge29 to thebase12 helps to provide for moulding efficiencies, such as but not limited to reducing the need for slider mould mechanisms (as is known in the art) as compared to forming piecewise membranes22 (seeFIGS. 16 and 17) partway in therim14, which extend from thelower edge29 to approximately midway to thehinge26. Further, it is recognised that the offset sidewall of thetab24 can help to position ejection forces of the moulding process away from theribs50.
• Referring toFIG. 21, an alternative embodiment of thelid10 is shown having both the offsettab24 and an offsetsidewall25, which consists of afirst sidewall portion25aand a second offsetsidewall portion25b. Provision of theadjacent tab portions24a, bandsidewall portions25a, bgives a continuous offset around therim14. For example, the outside surfaces of thetab portions24a, band therespective sidewall portions25a, bcan be flush with one another on either side of the interveningmembrane22.
• Referring toFIG. 22, it is noted that the inside wall of therim14 has aninset region68 located between thetab portions24a, bto help maintain consistency of the thickness of therim14. A taperedtransition portion70 positioned to either side of thetab24 helps to locally stiffen the connection between thetab portions24a, b(i.e. offset hinge64) to help maintain the structural integrity of thelid10 when installed on the container13 (seeFIG. 5), as well as to help transfer ejection forces from thelower edge29 to eject over therib50 andrib extending portions60. Thelid10 also has anangled abutment member72 located adjacent to thelower edge29 and oriented radially inwards from the inside surface of therim14. Theangled abutment member72 increases the thickness of therim14 near thelower edge29, thereby helping to increase a tendency for toe-in of the lower edge29 (warping of thelower edge29 radially inwards) during cooling of thelid10 in the moulding process. Further, theabutment member72 can also enhance stackability of thelid10 by providing a thickerlower edge29 for placement on thebase12 of an adjacent lid10 (not shown), outwardly of the stackingring46.
• Accordingly, thelid10 of FIGS.18 to22 includes an offset tab24 (and optional offset sidewall25) configuration for providing an offsethinge64 at the point of offset. The extendingportions60 overlap thefirst tab portions24ato interrupt the rupture of thefrangible membranes22, such that themembrane22 tearing is inhibited from damaging the integrity of therim14 between theribs50 and thebase12. The thickness of theribs50 and corresponding extendingportions60 are sufficient to resist tear continuation of themembrane22 past theribs50, and therefore restrict or otherwise localise separation of thetabs24 from thesidewall25 primarily to thesecond tab portions24b. Maintaining integrity of therim14 near thebase12 helps to provide a resealing capability to thelid10 once opened.
• Referring toFIG. 23, an alternative embodiment oflid10 is shown in a rectangular (or square) configuration. Thelid10 can also havevertical ribs74 positioned on thefirst tab portion24a.
• The above description is intended in an illustrative rather than a restrictive sense. Variations may be apparent to those skilled in the relevant art without departing from the spirit and scope of the invention as defined by the claims set out below.

Claims (29)

1. A tamper evident lid for mounting over an opening of a container having sidewalls with a lip extending outwardly therefrom to define said opening, said lid comprising:

a base;

a rim extending about said base for receiving said lip;

at least one resiliently flexible finger extending inwardly from said rim for engaging said lip, each said at least one finger having a length exceeding the distance between and inside of said lip and said sidewall and extending toward said base when said lid is mounted on said container; and,

at least one pair of frangible membranes spaced apart and formed in said rim and associated with at least one finger for facilitating tearing of said rim to disengage the at least one finger from said lip to enable removal of said lid from said container while leaving evidence of removal by way of a torn frangible membranes, the at least one finger disposed between the at least one pair of frangible membranes.

2. The tamper evident lid ofclaim 1 wherein:

said rim has an upper end adjacent to said base and a lower edge distal to said base;

and said frangible membrane extends from said lower edge toward said upper end.

3. The tamper evident lid ofclaim 1 wherein:

a respective of said frangible membrane is disposed on opposite sides of at least one said finger.

4. The tamper evident lid ofclaim 2 wherein:

at least a pair of said fingers is provided; and each one of said pair of fingers is disposed on an opposite side of said frangible membrane.

5. The tamper evident lid ofclaim 3 wherein:

said frangible membrane extends to a membrane hinge formed in at least one of said rim and said base; and,

said membrane hinge is positioned to facilitate disengagement of said at least one said finger from said lip upon tearing of said frangible membrane.

6. The tamper evident lid ofclaim 5 wherein:

said at least one said finger is disposed between said membrane hinge and said lower edge.

7. The tamper evident lid ofclaim 2 wherein:

said frangible membrane extends to at least one membrane hinge formed in said rim; each said at least one membrane hinge extends from said lower edge toward said base; and,

said at least one said finger is disposed in an area bordered by said frangible membrane, one of said at least one membrane hinge and said lower edge.

8. The tamper evident lid ofclaim 4 wherein:

said pair of fingers is disposed between a pair of membrane hinges extending from said lower edge toward said base; and, each said frangible membrane extends from said lower edge to each one of said pair of membrane hinges; and,

each said one of said fingers is disposed in an area bordered by said at least part of said frangible membrane, said membrane hinge and said lower edge.

9. The tamper evident hinge ofclaim 2 wherein:

a pair of radially spaced apart of said frangible membranes is provided with at least one of said at least one finger, disposed therebetween; and,

a membrane hinge extends across said base between said frangible membranes to facilitate disengagement of said fingers from said lip upon tearing of said frangible membranes by bending a portion of said base away from said lip.

10. The tamper evident hinge ofclaim 9 wherein:

a plurality of said fingers are disposed between said frangible membranes.

11. The tamper evident lid ofclaim 2 wherein:

at least one of said at least one fingers is a webbed finger having at least one web defined by a reduced thickness region extending toward said rim from a lip engaging end of said webbed finger which is distal said rim.

12. The tamper evident lid ofclaim 11 wherein:

each said webbed finger is provided with a passage therethrough in the form of a window to promote drainage of fluid trapped between said webbed finger and said rim.

13. The tamper evident lid ofclaim 1 wherein:

each said at least one finger has a profile selected from the group consisting of rounded, parallel faced straight, tapered narrowing toward said rim and tapered narrowing toward said rim with a scallop facing said container at an outer end thereof distal said rim.

14. The tamper evident lid ofclaim 13 wherein:

each said finger is curved in a direction generally corresponding to a curvature of said container to provide a lengthened contact zone with said lip.

15. The tamper evident lid ofclaim 13 wherein:

said rim has a recess extending from said fingers to said lower edge to accommodate said fingers to facilitate stripping of said lid in an injection moulding process.

16. The tamper evident lid ofclaim 13 wherein:

said fingers extend from said lower edge of said rim.

17. The tamper evident lid ofclaim 2 wherein:

from six to eight tear tabs are provided.

18. The tamper evident lid ofclaim 6 wherein:

at least one pull tab extends from said lower edge of said rim to facilitate tearing of at least one said frangible membrane.

19. The tamper evident lid ifclaim 18 wherein:

a stacking ring extends about said base and away from said rim to engage said lower edge of an adjacent of said tamper evident lid stacked thereupon to resist lateral shifting therebetween; and,

said stacking ring is one of segmented and continuous.

20. The tamper evident lid ofclaim 19 wherein:

a chamfer extends into said rim from said lower edge at the juncture of said frangible membranes and said lower edge to avoid a sharp corner at said juncture upon tearing of said frangible membrane.

21. The tamper evident lid ofclaim 2 further compromising a respective of said frangible membrane dispensed on opposite sides of at least one of said finger to provide a tab portion partially detachable from a sidewall portion of the rim.

22. The tamper evident lid ofclaim 21, wherein the tab portion further comprises a first tab portion depending from said upper end and a second tab portion depending from said first tab portion toward said lower edge, said second tab portion is a detachable from the sidewall portion.

23. The tamper evident lid ofclaim 22 further comprising a rib extending inwardly from the sidewall portion of the rim, the rib having an extension portion overlapping both said first tab portion and an adjacent one of the frangible membranes, the extension portion for inhibiting tearing of the adjacent frangible membrane associated with the first tab portion.

24. The tamper evident lid ofclaim 23, wherein the rib and the extension portion are configured for engaging said lip to retain said lid on said container once mounted thereon.

25. The tamper evident lid ofclaim 23, wherein respective extension portions overlap said first tab portion and each of the adjacent frangible membranes on opposite sides of the first tab portion to inhibit tearing of the adjacent frangible membranes associated with the first tab portion.

26. The tamper evident lid ofclaim 25 further comprising an interrupted portion located between the extending portions for allowing said finger to flex outwardly towards a retracted position against the inner surface of the tab portion.

27. The tamper evident lid ofclaim 22 further comprising an offset wall between said first tab portion and said second tab portion to define an offset hinge, the offset hinge for promoting bending of the tab portion between the first and second tab portions upon tearing of the said frangible membranes.

28. The tamper evident lid ofclaim 27, wherein respective extension portions overlap the adjacent said frangible membranes on opposite sides of the first tab portion to inhibit tearing of the adjacent said frangible membranes associated with the first tab portion.

29. The tamper evident lid ofclaim 2, wherein a pair of the fingers is disposed between the pair of frangible membranes.

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