One-piece molded flip cap closure

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.

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.

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 110a. The tamper-evident structure 110a 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. 
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'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's 38 shape memory as previously 
explained. The props 102 and 104 preferably maintain the cap 38 at a 
ninety 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 full 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.