Abstract:
A closure for a container and a method of producing the same is set forth. The closure is a single integrally-molded spout, cap, hinge assembly joining the spout and the cap, and a tamper evident structure. The closure may also have a membrane and pull-ring, also integrally molded as one piece. The cap may have at least one prop for preventing interference from the cap with the pouring of the contents of the container. Additionally, the spout may have a step for assisting in the prevention of interference from the cap during pouring, and for providing a predetermined sound every time that the cap is opened. Still further, the closure may have an orienting peg for properly orienting the closure on a container.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This application is a continuation of U.S. Provisional Patent Application No. 60/030,312, filed on Nov. 1, 1996, which is hereby incorporated by reference. 
     This application is a continuation of U.S. application Ser. No. 09/958,996, filed Oct. 28, 1997, now U.S. Pat. No. 6,003,712. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to closures for food packaging. Specifically, the present invention relates to a one-piece flip-cap closure for use in food packaging having a tamper-evident structure thereon. 
     2. Description of the Related Art 
     Resealable closures are now commonly employed on, for, example, gable-top containers. The closures are generally snap-type caps or screw-type caps which are removable from and resealable over an opening of a corresponding spout. Such closures desirably include tamper-evident features to enable a retailer or consumer to determine whether the closure has been opened before. 
     Conventional closures have certain limitations. For one thing, the closures themselves can be quite costly to produce, frequently being formed from two or more separate parts formed in two or more separate molds using two or more separate injection molding processes and two or more different materials. Even where a single mold is used, costly and complex laterally moving mold elements which move perpendicular to the primary mold closing direction may be required. 
     Another problem with many closures is the requirement for difficult and expensive assembly operations for finishing the closures and installing them on containers. These operations can require expensive tooling. Even the parts of a simple threaded cap and spout closure for installation through a panel of a gable top container must be separately molded, positioned in relation to each other, assembled, and then held in place in some fashion (such as by installing a tamper-evident joint at the same time) as the cap does not loosen and potentially fall off. These operations are conventionally carried out by the manufacturer of the closures, which are shipped in bulk to the food packager. The food packager must then retrieve each assembled closure from its bulk container, orient it in a packaging machine, and secure the closure to the package as it is assembled and (usually) before it is filled. 
     A closure with a snap-on cap joined to the spout by an integral hinge is somewhat easier to assemble, in that the cap and spout, and in some instances the tamper-evident structure, are already located in preestablished positions by molding them as one piece. But snap-on closures often require complex assembly and joining operations to initially close them and place their tamper-evident structure in its operative position. For mass-production closures, complex machinery is required to carry out the assembly operation. Too often, the closure must be assembled in one or more steps, closed in one or more steps, and installed on the container in one or more steps. The entire manufacturing process can thus include many steps, and many duplicate steps (such as multiple heat sealing operations conducted on different machinery at different times). 
     The closure assembly must be inserted cleanly through a relatively small aperture in the container when the closure is installed. Commonly, the spout, cap, tamper-evident structure, and other closure elements are inserted through an aperture slightly greater in diameter than the spout, from the inside of the container. If the parts of the closure are not tied securely together and properly located during assembly, one or more appendages of the closure can be dislocated. At a minimum this can result in rejected containers. Worse, the automated mechanism for assembling closures or containers can jam, necessitating a shut-down to correct the problem. 
     Closures are known which have an impervious membrane or web closing the spout before use and a tear ring located within the spout. In many instances, the tear ring is recessed in the spout, and can be grasped only by inserting a finger into it and pulling it out of the spout to tear and remove the membrane or web and open the spout for use. One difficulty with many such tear rings is that a person with large fingers, or a person using one of his or, her larger fingers or a thumb, or a person lacking in dexterity, has difficulty inserting a finger in the recessed ring. The inaccessible edge of the recessed ring cannot be manipulated. The ring is thus difficult to lift out of place so it can be grasped more firmly. 
     If the entire ring is simply elevated above the mouth of the spout in the same orientation (usually, parallel to the membrane), space must be left under the entire cap to accommodate the elevated ring or tab, thus providing a high-profile closure which projects a substantial distance above the panel in which the closure is mounted. A high profile closure is undesirable, as it can be unsightly and may require more material than a low-profile closure of the same diameter. A high-profile closure mounted on a diagonal top panel of a gable-top container also may project through the plane of the side panel of the container, interfering with packing operations. 
     Another issue regarding closures is the desirability of forming a closure from polyethylene, which can be heat-sealed or ultrasonically sealed directly to a polyethylene coated paperboard panel or a polyethylene bottle, as opposed to forming the closure from another plastic which must be glued to polyethylene. Gluing is a less desirable and less sanitary assembly method than heat or ultrasonic sealing, in general. 
     While polyethylene closures are easily installed on polyethylene-coated paperboard and other surfaces by heat or ultrasonic welding, polyethylene has other characteristics which must be dealt with when designing a closure. For example, polyethylene, unlike polypropylene and other plastics, readily inelastically deforms or relaxes during storage, and thus has little springiness or “memory” of its configuration as molded. 
     For example, assume that a cap, spout, and integral hinge assembly is molded in an open configuration with the inverted cap beside the upright spout and the hinge straight, then the hinge is folded in a “U” shape to position the cap upright above the spout, and the cap is pushed down on the spout. Next, assume the closure is stored for a time, then installed on a container, which is filled, closed, transported, stored for another time, then finally placed in the hands of a consumer. 
     If the closure is made of polypropylene, when the consumer finally opens the closure, the hinge will be springy or have a “memory” of being open when it was originally molded. The cap will thus spring out of the way of the spout, and not block or be soiled by a stream of fluid contents poured from the spout of the container. 
     If, however, the closure is made in the same way of polyethylene, the plastic will have relaxed during storage and the cap will not spring out of the way of the spout to the desired degree when the closure is opened. This problem requires the consumer to make a special effort to hold the cap out of the way when dispensing the contents of the container, or to risk soiling the cap and thus providing an unsanitary or unsightly closure. 
     Accordingly, the inventors have recognized that a need remains within the industry for an improved closure which assists in overcoming the disadvantages experienced in the past and discussed above. 
     BRIEF SUMMARY OF THE INVENTION 
     A closure for a container is set forth which comprises an integrally-molded spout, a cap, a hinge or other link joining the spout and the cap, and tamper-evident structure joining the spout and the cap. The tamper-evident structure includes a first portion secured to the cap (alternatively, to the spout) by a first breakable joint and a second portion secured to the first portion by a second breakable joint. The second portion is movable toward the spout (alternatively, toward the cap) as molded, but can be positioned and attached at least substantially in direct contact with the spout (alternatively, with the cap) while the cap is sealing the spout, in the course of assembling and securing the tamper-evident structure. 
     It is a primary object of the present invention to provide a closure having a spout, cap and tamper-evident structure formed as a single integral piece. 
     It is an additional object of the present invention to provide a closure having a prop for preventing interference from the cap during pouring of the contents from the spout. 
     It is an additional object of the present invention to provide a closure having an orienting pin integrally formed with the closure. 
     It is an additional object to provide a closure having a pull ring oriented for facilitated removal of a membrane attached thereto. 
     Having briefly described this invention, the above and further objects, features and advantages thereof will be recognized by those skilled in the pertinent art from the following detailed description of the invention when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     Several features of the present invention are farther described in connection with the accompanying drawings in which: 
     There is illustrated in FIG. 1 a top perspective view of a preferred embodiment of a closure of the present invention prior to folding closed; 
     There is illustrated in FIG. 2 a top perspective view of a preferred embodiment of a closure of the present invention in the sealed or closed position; 
     There is illustrated in FIG. 3 a top plan view of the closure of FIG. 1; 
     There is illustrated in FIG. 4 a front perspective view of the closure of FIG. 1; 
     There is illustrated in FIG. 5 a side view of the closure of FIG. 1 sealed; 
     There is illustrated in FIG. 6 a side view of the closure of FIG. 1 with the tamper evident structure open; 
     There is illustrated in FIG. 7 a top perspective view of an alternative embodiment of a closure of the present invention prior to folding closed; 
     There is illustrated in FIG. 8 a top perspective view of the closure of FIG. 7 in the sealed or closed position; 
     There is illustrated in FIG. 9 a side perspective of the closure of FIG. 7 attached to a gable-top carton; 
     There is illustrated in FIG. 10 a front perspective view of the closure of FIG. 7; 
     There is illustrated in FIG. 11 a side view of the closure of FIG. 7 sealed; 
     There is illustrated in FIG. 12 a side view of the closure of FIG. 7 with the tamper evident structure open; 
     There is illustrated in FIG. 13 a top perspective view of an alternative embodiment of a closure of the present invention; 
     There is illustrated in FIG. 14 a top perspective view of the closure of FIG. 13 prior to folding closed; 
     There is illustrated in FIG. 15 a front perspective view of the closure of FIG. 13; 
     There is illustrated in FIG. 16 a side view of the closure of FIG. 13 sealed; 
     There is illustrated in FIG. 17 a side view of a closure of present invention as formed in a mold; 
     There is illustrated in FIG. 18 a side view of the closure of FIG. 17 after removal of the closure from the mold and during the folding process; 
     There is illustrated in FIG. 19 a side view of the closure of FIG. 17 fully folded over for distribution; 
     There is illustrated in FIG. 20 a side view of the closure of FIG. 17 with the tamper-evident structure partially folded; 
     There is illustrated in FIG. 21 a side view of the closure of FIG. 17 with the tamper-evident structure filly folded; 
     There is illustrated in FIG. 22 a bottom plan view of the closure of FIG. 17; 
     There is illustrated in FIGS. 23-25 an alternative embodiment of the present invention; 
     There is illustrated in FIG. 26 a flow diagram of the method of producing the closure of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     There is illustrated in FIGS. 1-6 an embodiment of a re-sealable closure  30  that may be utilized, for example, in conjunction with a gable-top container  31  (see FIG. 9) having a body formed from a paperboard-based substrate that is disposed between outer layers of a thermoplastic polymer material. The closure may also be used with a non-paperboard based polyethylene container, or with other types of containers generally. 
     The closure  30  is formed as a single, integrally molded piece and generally includes a spout  32  having a stem  34  which is tubular in shape and projects upward from an annular base flange  36  extending about the periphery of the lower end of the stem  34 . The base flange  36  has a generally circular shape except for a flat portion  37 . The flat portion  37  is optional and assists in orienting the closure  30  during placement on a container  31 . The spout  32  is joined with a cap  38  by an integral hinge assembly  40 . 
     The cap  38  resealably engages the stem  34  of the spout  32 . In the particular embodiment illustrated here, the cap  38  includes an upper lid  42  surrounded by a downwardly projecting skirt  44 . The upper lid  42  may have a beveled edge  43  as a transition between the upper lid  42  and the skirt  44 . The skirt  44  and lid  42  cooperate to define a vaulted interior cavity which receives an upper portion of the stem  34  when the cap  38  is secured about the stem  34  to close the closure  30 . 
     An annular recess  46  is formed about the interior of the cap  38  near the intersection of the skirt  44  and the lid  42 . An interior surface of the skirt  44  includes an inner rib  48  extending about its interior. The lid  42  and the rib  48  cooperate to define the recess  46  between them. 
     The stem  34  includes an upper end  50  having an outwardly flared lip  52  extending about the exterior periphery of the stem  34 . The lip  52  engages the recess  46  of the cap  38  when the closure  30  is in a closed position. The skirt  44  includes a beveled surface  54  at its mouth to enable the cap  38  to be easily guided over the lip  52 . The lip  52  and rib  48  engage one another to seal the cap  38  over the stem  34 . The stem  34  further includes an aperture  56  to enable the contents of the container  31  to be poured out when the cap  38  is removed. 
     Within the spout  32 , an optional membrane  58  may be disposed over the aperture  56 . The membrane  58  is a web integrally formed within the stem  34 , in this embodiment. The intersection of the membrane  58  and the interior surface of the stem  34  defining the aperture  56  is weakened by the circular groove  60  defining that intersection. 
     The membrane  58  includes an integral pull ring  62 , optionally formed at least approximately concentrically with the stem  34 . The pull ring  62  is secured to the membrane  58  by a post  64  which is integral with the membrane  58 . The pull ring  62  has a post side  66 , a free side  68  approximately diametrically opposed to the post side  66 , an inner surface  70 , and an outer surface  72 . 
     FIGS. 7-12 illustrate another embodiment  150  of the closure. One distinguishing feature of the closure  150  is the shape of its cap  152 , which has a generally flat lid  154 . The shape of the cap  152  affords a closure  150  having an extremely low height or profile. The height of the closure  150  can be the sum of the height of the lip  52  above the flange, plus the thickness of the lid  154 , minus the thickness of the container wall through which the closure is inserted. 
     The generally cylindrical skirt  156  of the cap  152  is also modified to make the cap  52  easier to close on the stem  34 . The hinged side  158  of the skirt  156  is shorter than the swinging side  160  of the skirt  156 . This change slightly increases the diameter of the mouth  162  of the skirt  156  from the hinge side  158  to the swinging side  160 , without decreasing its diameter in the perpendicular direction, and without changing the diameter of the skirt  156  measured parallel to the lid  154 . The increased long diameter of the oval mouth  162  allows it to more easily capture the portion of the lip  52  which is diametrically opposed to the hinge assembly  40  than a round mouth could do. Yet, the skirt  156  remains circular in its cross-sections perpendicular to the axis  164 , so the skirt  156  mates with the entire circumference of the stem  34  as in the first embodiment. 
     Another difference between the closure  150  of FIGS. 7-12 and the closure  30  of FIGS. 1-6 is that the closure  150  lacks an integral sealing membrane  58  and pull ring  62 . A separate membrane tape or patch can be applied to the inside of the container,  31  to cover the base flange  36 . Alternatively, for some purposes the seating relation of the cap  152  and the spout  32  may be sufficiently fluid-tight, particularly with the tamper-evident structure  110  intact, to allow the membrane  58  to be eliminated. 
     A third embodiment of the invention, generally indicated as  180 , is illustrated in FIGS. 13-16. This embodiment has a different tamper-evident structure, here denoted as  110   a.  The tamper-evident structure  110   a  is only on one side of the cap  38 . This allows for costs savings in material and is easier to fabricate. Also, the cap has a rounded lid as opposed to the beveled lids and flats lids of the other embodiments. The cap  38  can include a logo or design such as indicated at L. 
     A tamper-evident structure  110  is shown in each of the embodiments of FIGS. 1-16. Referring to FIGS. 1-16, the tamper-evident structure  110  is formed integrally with the cap  38 . It should be appreciated, however, that the tamper-evident structure  110  and the cap  38  do not need to be adjacent as molded. The closure  30  could be rearranged to interpose other structure, such as the spout  32 , between the tamper-evident structure  110  and the cap  38  as molded. The same is true of other structures identified herein as being “integrally formed”, and thus attached directly or indirectly to one another. 
     In this embodiment, the tamper-evident structure  110  includes a first portion  112 , here a tear strip, secured at least substantially directly to the cap  38  (as here) or the spout  32 . Here, the tear strip  112  is linked to the cap by a first breakable joint defined by the weakened integral hinge portions  114  and  116 . The structure  110  further includes a second portion  118  secured to the tear strip  112  by a second breakable joint  120 . As molded, the second portion  118  is movable with respect to the “other one” of the cap  38  and spout  32  not as directly attached to the tear strip  112  (here, the spout  32 ). Any one of the integral hinges  92 ,  96 ,  114 ,  116 , and  120  renders the second portion  118  movable with respect to the spout  32 . 
     The second portion  118  is adapted for being positioned and attached at least substantially in direct contact with the other of the cap  38  and the spout  32  (here, directly to the spout  32 ) while the cap  38  is sealing the spout  32 , in the course of assembling the tamper-evident structure  110 . 
     As one of ordinary skill in the art will appreciate, two elements “substantially in direct contact” or “secured at least substantially directly” or “linked to the cap” as described above are linked more directly than merely being parts of the same one-piece molding (as all the structure in the closure  30  is related to this degree), but may be linked less than directly together with other structure intervening. The limit of a “substantially direct” link of securement is regarded as a wording problem, not a technical problem. 
     For the present purposes the complete, unopened closure  30  has the requisite substantially direct connection between two elements if they are attached by some structure parallel to the hinge assembly  40 , so that if the hinge assembly  40  were severed the two elements in question would still be attached by the parallel structure. 
     The second portion  118  is attached substantially directly to the base flange  36  of the spout  32 , in this embodiment, by inserting the second portion  118  into a complementary recess  122  in the base flange  36 . In this embodiment, the recess  122  is diametrically opposed to the recess  98 , though this relation is not essential to the invention. In this embodiment the recess  122  has a stud  124  which snaps into an aperture  126  in the second portion  118 , to affirmatively locate the second portion  118  in the recess  122 . The recess  122  and the second portion  118  could themselves be provided with a snap fit instead, or as well. 
     When the second portion  118  and recess  122  are permanently joined (which is preferably done at the same time as the closure  30  is secured to a container  31 , as described below), the cap  38  is connected by a first breakable joint  114  of  116  to the tear strip  112 , which in turn is connected by a second breakable joint  120  to the spout  32 . The tear strip  112  is adapted to be torn away and discarded to subsequently release the cap  38  so the closure  30  can be opened. 
     Even if a tamperer chooses to cut away the stronger second breakable joint  120 , leaving the joint  114 / 116  in place, to obscure the fact that the closure  30  has been opened, it will be evident to the purchaser, when tearing away the strip  112 , that it “gives” too easily and therefore the closure has been tampered with. The closure also, here, has a separate membrane seal  58  as a further guard against tampering with the contents of the package bearing the closure  30 . 
     The tear strip  112  has first and second wings or tabs  128  and  130 , each of which can include ribs such as  132  so they can be grasped more easily. The tabs  128  and  130  have free top edges  134  and  136  and feet  138  and  140 . 
     When the closure  30  is closed initially, the tear strip  112  is, at or near the same time, swung into its operative position about the breakable joints  114  and  116 . The second portion  118  is positioned in the recess  122 . The tabs  128  and  130  bear against (and are optionally spread apart a little from their as-molded separation by) the stem  34 . The feet  138  and  140  bear against the base flange  36 , which tends to urge the second portion  118  into the recess  122 . The free top edges  134  and  136  of the tabs  128  and  130  extend above the skirt  44  of the cap  38 , so a user can readily push either of the tabs  128  or  138 , urging it away from the cap  38  to enable the user to grasp the tab  128  or the tab  130  between the user&#39;s thumb and index finger. This affords a secure grip, so the tear strip  112  can be torn away. Two tabs,  128  and  130 , are provided in part so that the tear strip  112  can be conveniently torn away with either hand. Right-handed and left-handed people can thus use the closure  30  equally well. 
     With particular reference to FIGS. 17-22, the integral hinge assembly  40 , as molded, includes an L-shaped link  88  having a first portion  90  connected to the flange  36  by an integral hinge  92  and a second portion  94  attached to the cap  38  by an integral hinge  96 . The first portion  90  in this embodiment is about as long as the width of the flange  36 , at least in the area of the hinge assembly  40 . The second portion  94  can be shorter than the height of the stem  34  in the area of the hinge assembly  40 . 
     The first portion  90  is sized and shaped, and the integral hinge  92  is sufficiently flexible, to allow the first portion  90  to be pivoted into, and in this embodiment just fill, the recess  98  in the base flange  36 . The second portion  94  elevates the lower margin of the skirt  44  above the base flange  36 , thus reducing the necessary height of the skirt  44  and saving material, while reducing the necessary clearance between the inner circumference of the mouth of the skirt  44  and the outer circumference of the lip  52 . 
     The cap  38  includes a pair of integral props  102  and  104  on the respective sides of the hinge assembly  40 . When the cap  38  is opened for pouring the contents of a container  31  through the spout  32 , the props  102  and  104  are nearly perpendicular to and bear against the stem  34  to keep the cap  38  clear of the emerging contents of the container  31 . This is necessary due to the tendency of the cap  38  to partially reseal during pouring due to the effects of gravity and the cap&#39;s  38  shape memory as previously explained. The props  102  and  104  preferably maintain the cap  38  at a forty-five degree angle to the top of the stem  34 . When the cap  38  is closed, the props  102  and  104  sweep down the stem  34  and are stowed against or near the stem  34  and nearly perpendicular to the base flange  36 . 
     As illustrated in FIGS. 17-22, the closures  30 ,  150  and  180  are formed as a single piece, preferably from a heat sealable thermoplastic material such as polyethylene, by injection molding or the like. The closure  30  may be advantageously molded within a single injection molding tool in its expanded position illustrated in FIG.  17 . Such a molding tool is both simple and economical to form. Additionally, such a tool is easy to maintain. Overall, the single, integral structure shown here gives rise to a closure  30  that is more economical to manufacture than other closures  30  in common use today, such as those comprising separate cap  38  and spout  32  sections. Once the closure  30  is formed, it is folded over. This folding occurs subsequent to removal from a mold and also subsequent to at least partial cooling of the closure  30 . As shown in FIG. 19, the cap  38  is completely folded over to engage with the spout  32 . 
     Another feature of the present invention is an orientation peg  142  which projects from the base flange  36  and is eccentrically positioned relative to the center of the closure  30 . The peg  142  can be provided by leaving a short column of the material formed in a runner of the mold cavity leading to the underside of the closure  30  when the superfluous material is trimmed from the closure  30 . 
     The orientation peg  142  can be used to orient the closure  30  when it is to be used in a packaging machine. This step is necessary because the closures  30  are conventionally packed in random orientation in a bulk carton, but each closure  30  should face in the same direction when installed on a package. 
     The assembled and oriented closure  30  is inserted into an aperture of a container  31 . Preferably, the closure  30  is inserted to the position shown in FIG. 9 so that the flange  36  engages the interior, thermoplastic surface of the container  31 . Alternatively, the flange  36  may engage the exterior, thermoplastic surface of the container  31 . 
     The closure  30  is preferably secured to the container  31  by ultrasonic sealing, heat sealing, pressure sealing, or combinations of these types of sealing mechanisms. Using these types of sealing, the interior thermoplastic layer of the container  31  and the material of the base flange  36  are melted and the interface between them is substantially eliminated (i.e. they are welded) to secure the flange. An ultrasonic sealing horn may be readily configured to surround the cap  38  and stem  34  and engage the area of the exterior of the container  31  about the flange  36  to permanently secure the flange  36  to the container  31 . 
     One particular advantage of the present invention is that the sealing force for permanently assembling the hinge assembly  40  to the base flange  36  can be applied by the mechanism-which joins the base flange  36  to the container  31 . The ultrasonic, heat, or other energy applied to the flange  36  to seal the flange  36  to the container  31  also heats the first portion  90  of the L-shaped link  88  and the flange walls defining the recess  98 , sealing them together. Once this is done, the recesses  98  is fall of plastic and thus no longer interrupt the otherwise smooth, generally annular base flange  36 . 
     In the illustrated arrangement, the first portion  90  and the recess  98  are both positioned between the base flange  36  and the inner wall of the container  31  when the assembly is welded together. As a result, most cosmetic imperfections caused by filling the recesses in the base flange are not visible from outside the container  31 . 
     A standard packaging machine may be used to form the closure  30  and seal it to the container  31  with a minimal amount of additional tooling. This is due, at least in part, to the fact that only one sealing tool, for example an ultrasonic sealing tool, is needed to facilitate the sealing. Thus, the overall cost for tooling is reduced, while part production costs and production maintenance is reduced by utilizing a single-piece, low maintenance injection molding tool in the molding process. A further advantage is that the present closure  30  design can be preferably manufactured through a process in which the molding tool is only moved along a single axis running in the mold parting and closing direction. 
     Alternative, although generally less efficient, processes for, securing the closure  30  to the container,  31  are also contemplated. For example, adhesives may be used to join the parts of the closure  30 , or to attach the closure  30  to a container  31 . 
     FIGS. 23-25 show still another closure, which is a two-piece closure  192  including a cap  194 , a spout  196 , a flange or shoulder  198 , and a tab  200  attached to the cap  194  by a weakened integral hinge  202 . In this embodiment, the cap  194  can be a screw cap or a snap-on cap. The spout  196  and flange or shoulder  198  can be parts of an independent closure, as before, or parts integrally molded as parts of a bottle or other container. 
     Once the cap  194  is snapped or otherwise attached to the spout  196 , the tab  200  is secured by ultrasonic, heat, adhesive, or other means to the flange  198 . Again, the cap  194  is removed forcefully to break the weakened integral hinge  202 , after which the cap  194  can be removed or replaced repeatedly. In this or the preceding embodiment, more than one of the tabs  184  or  200  can be provided about the circumference of the flange such as  198  to form multiple tamper-evident joints. 
     The present closures can be molded in one shot, as a single part, in one two-part mold which does not require laterally traveling mold elements. 
     A simple folding step can be employed to position the cap, the spout, and the tamper-evident tear strip from their as-molded positions to their closed positions, without requiring “tacking” or other heating operations. The closure can be snapped shut reasonably securely, without gluing or welding its parts together, so it will remain closed during handling and can easily be inserted cleanly through a small aperture in a container. 
     An orientation peg, optionally formed as a vestige of the plastic remaining in a mold runner, can be provided to cause the closure to self orient with its hinged side trailing when sliding down an incline. The orientation ability of the inclined surface may be accentuated by roughening the surface of the incline. 
     The closure can have a pull ring for breaking and removing a sealing membrane within the spout. The pull ring can be positioned with its free side projecting above the rim of the spout at one point in the spout circumference. The pull ring can be contacted on the outside with a finger and pushed further up to permit it to be grabbed. If molded polyethylene (which provides heat-sealability to polyethylene coated board but little resilience), the cap can be vaulted to provide interior room for accommodating the raised part of the pull ring. 
     The vaulted cap of the closure can be provided in an aesthetically pleasing configuration which still has a relatively low profile. The low profile configuration can also have functional features, such as a front raised surface which extends vertically from a slanted panel of a gable top container so it will not project through the plane of any of the side panels of the container. 
     The cap can have one or more molded-in legs extending from the cap near the hinge. The legs will erect against the outside of the spout  32  when the cap  38  is opened to hold the cap  38  out of the way of the spout  32 . These legs can fold against the spout  32  when the cap  38  is closed. This allows the closure  30  to be molded of easily sealed polyethylene, which has no memory and inelastically deforms during storage. 
     The tear strip of the tamper-evident structure can be bifurcated by providing a separate pull tab on each of its ends so the closure can be opened equally well by left or right-handed people. 
     The tear strip can be molded half-round and out of position so its tabs fit snugly against the cap when folded into position. This feature prevents the tear strip from catching in the aperture through the wall of the container during assembly. 
     The top edges of the tabs extend above the top of the skirt of the cap. Each of the top edges is easy to push away from the cap so one of the tabs can be securely grasped to tear away the tear strip and open the closure. The feet of the tear strip contact the base flange of the closure when the tear strip is folded into place and the closure is closed. This contact rotates the tear strip, tending to urge the second portion of the tamper-evident structure into a recess in the base flange. 
     The closures can be easily assembled to their closed positions, and their parts and appendages can stay in their closed positions during further handling without requiring any welding operations or the like. The sealing operations necessary to provide a closure durable enough for use can be carried out at the same time the closure is joined to a container wall, using the same ultrasonic tool or other energy source, fastener, or adhesive used to attach the closure to an inside wall of the container. This expedient saves a manufacturing step and avoids deformation of the closure which could be caused by a plastic welding operation carried out on the closure before installing the closure in a container. 
     The flat cap alternatively provided in the closure can have an exceedingly low profile. The swinging side of the skirt of the closure can be deeper than the hinged side of the skirt. This configuration allows the mouth of the cap to reach slightly further to capture the fee side of the lip of the stem. 
     There is illustrated in FIG. 26 a flow diagram of the method of producing the closure of the present invention. As shown in FIG. 26, at step  400  a mold is provided for a closure. The mold may be on a injection molding machine which may also have additional molds with a preferred number being 64 molds. At step  402 , the mold is filled with a polymeric material to be formed into an integral one-piece closure. A preferred polymeric material is polyethylene, however, other polymeric materials may be used in fabricating the closure. At step  404  the mold is opened and a means of conveyance is provided to conveyor the closure from the molding machine to a folding machine. The conveyance means may be flat arm having partitioned areas for receiving a closure. At step  406 , the closure is attached to the conveyance means. This may occur through pushing of the closure out from the mold by means of a pin. The conveyance means may also have a vacuum for receiving the closure. 
     At step  408 , the closure is conveyed to an adjacent folding machine. At step  410 , the closure is delivered from the conveyance means to a reorienting means. The closure is placed on the reorienting means with the bottom of the spout and the top of the cap facing outward in an unfoldable orientation. The orientation is unfoldable in that the hinge assembly would be broken if folded, and the spout would not be covered as desired. The reorientation means may be a flat sheet having a groove with or without a vacuum for accepting the closure. At  412 , the reorientation means moves and attaches the closure to a folding device thereby reorienting the closure to a foldable orientation with the bottom of the spout and the top of the cap facing inward. At step  414 , the cap is folded onto the spout by the folding device. The folding device may operate similar to a door hinge in folding the cap onto the spout. At  416 , the closure is released from the folding device onto a conveyor mechanism disposed below for packaging and distribution. 
     From the foregoing it is believed that those skilled in the pertinent art will recognize the meritorious advancement of this invention and will readily understand that while the present invention has been described in association with a preferred embodiment thereof, and other embodiments illustrated in the accompanying drawings, numerous changes, modifications and substitutions of equivalents may be made therein without departing from the spirit and scope of this invention which is intended to be unlimited by the foregoing except as may appear in the following appended claims. Therefore, the embodiments of the invention in which an exclusive property or privilege is claimed are defined in the following appended claims: