US20100140268A1

US20100140268A1 - Dispensing closure with removable membrane

Info

Publication number: US20100140268A1
Application number: US12/704,650
Authority: US
Inventors: Richard D. Lohrman
Original assignee: Portola Packaging Inc
Current assignee: Portola Packaging Inc
Priority date: 2003-05-27
Filing date: 2010-02-12
Publication date: 2010-06-10
Also published as: WO2011100394A1

Abstract

In an embodiment of the invention, there is provided a closure for a container having a container opening. The closure includes lower and upper separable component closure pieces secured to one another. The lower component includes a removable membrane that may be removed by the opening of a top contained in the upper component. The top is further permitted to be removed from the closure without detaching the lower component from the container.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation in part of U.S. Application Ser. Nos 11/929,160 and 11/929,009, both filed Oct. 30, 2007 and both pending, which are continuation in part of U.S. application Ser. No. 11/610,217, filed Dec. 13, 2006 and pending, which is a continuation in part of U.S. application Ser. No. 10/854,925, filed May 26, 2004 and pending, which claims priority to U.S. Provisional Application Ser. No. 60/473,847 filed May 27, 2003. The entire contents of the above identified applications are herein incorporated in their entirety by this reference.

BACKGROUND

Over the past few decades removable membranes have become ubiquitous in packaging to achieve a combination of consumer convenience and protection of product integrity prior to use. These removable membranes serve as a primary seal prior to initial removal. Moreover, their removal on initial package opening serves as a tamper evidencing indication.
The removable membrane closure systems are often accompanied by an additional closure which serves primarily as a dust cover prior to initial opening and as a reclosure cap after opening and the removable membrane is removed. In normal use, the additional closure is removed on initial opening to access the removable membrane. After removing the removable membrane to access the contents, the package is reclosed with the additional closure to create a multiple use package.
One form of removable membrane comprises a foil that is heat sealed to the upper lip of a container after filling with contents. The foil membrane is removed, by simply pulling off wherein the heat sealed joint is ruptured. Another form of removable membrane comprises a monolithic plastic structure wherein a thin plastic membrane is joined to a primary closure body through a frangible score line. In this case the package is initially opened by tearing out the removable membrane along the frangible line.
Prior art membrane closures have often employed multiple components to achieve the desired functional benefits. A first component is the foil itself or a membrane frangibly attached to structure suitable for attachment to the container. The second component is normally the above mentioned reclosure cap. Typical examples of such a prior art membrane closure systems are taught in U.S. Pat. No. 5,810,184 and U.S. patent application Ser. No. 11/929,009, the entire contents of which are incorporated herein by reference.
In the case of heat sealed foil membranes, additional filling line complexity results from the necessity to heat seal the foil after filling the container. In addition, removal of the foil on initial opening often remains an inconvenience. The heat sealed foil most often has very little accessible surface to grab, and the strength of the heat sealed bond can vary and often be very strong. These factors often make it necessary to puncture the foil with a sharp instrument before manual removal. This can be messy and even hazardous.
Plastic membranes are not so limited, since they are manufactured with pull tabs which facilitate initial membrane removal. However, the plastic membranes are supported and frangibly joined to additional structure suitable for engagement to the container. Should this attachment structure be readily disengaged without a tampering indication, the tamper evident aspect of the membrane removal could be circumvented. Thus the attachment is often designed to be at least semi-permanent so that the only access to the contents is to remove the membrane. However, semi-permanent or permanent attachment to the container can lead to mixed material recycling streams which complicates recycling efforts.
Municipalities are becoming increasingly sensitive to mixed material contamination of recycling streams. Of particular interest is the presence of colored closures accompanying clear or natural plastic containers. Here the colorant in the closure may adversely affect the natural color of the recyclate. Of even more significance is the incompatibility which may result from mixing different materials. For example, small amounts of polyolefin closures may adversely affect the properties of PET container recycling streams. Therefore, municipalities are increasingly advising residents to completely remove and discard closures prior to discarding containers into recycle bins.
One such effort to facilitate complete removal of the closure from the container is taught in PCT/US09/58029 filed Sep. 23, 2009 which claims priority to U.S. Provisional Application Ser. No. 61/179,569, filed May 19, 2009. The entire contents of PCT/US09/58029 are herein incorporated in their entirety by this reference. In that application, a single piece closure was taught having a hinged top member monolithically attached to a base comprising a pull-out membrane. Upon package exhaustion, the entire closure may be removed by pulling on the top member to sever frangible lines extending from the top through the skirt portion of the base.
While effectively addressing the recycling issue, the single piece, monolithically formed closure of PCT/US09/58029 anticipates both the frangible membrane structure and the hinge structure to be formed from the same material, normally low density polyethylene, to achieve facile tearing of the frangible lines. Unfortunately, low density polyethylene is inadequate in forming the best, robust snap hinges favored by consumers.
A further problem that must be addressed with the single piece design is that when pulling on the lid to sever the tear lines extending through the base skirt, an upward force is preferentially directed at a defined, fractional portion of the skirt's circumference. It has been found that in some cases this localized force is sufficient to overcome the gripping force of the tamper evident structure retaining the closure to the container. This raises concerns about the tamper evidencing of the package design and forces increased structure to resist the localized force.
Thus there remains a need for continued improvements in the technology of producing a closure offering the convenience of a removable plastic membrane removal yet not contributing to recycling problems associated with mixed material.

OBJECTS OF THE INVENTION

The instant invention solves the stated problems associated with prior art removable membrane closure systems by offering a structure wherein the membrane can be initially removed without removal of the main body of the closure from the container.
A further object of the invention is to permit facile removal of a portion of the closure structure from the container after exhausting its contents such that the container recycling stream is not negatively impacted by mixed or colored materials.
A further object of the invention is to teach a closure design which combines the convenience of a hinged top closure with the convenience of an initial plastic pull-out membrane seal.
Other objects of the invention will become clear in light of the following specification and drawing embodiments.

SUMMARY OF THE INVENTION

In an embodiment of the invention, the two piece arrangement allows a hinge structure to be made of polypropylene, the preferred material to make a strong, robust living hinge, and at the same time allows making a frangible tear out membrane from polyethylene, the preferred material for a tearable membrane.
In an embodiment, the two piece arrangement requires no tear lines depending downward from the hinge. From a recycling standpoint, the colored, hinged overcap is easily removed after use and discarded. The natural polyethylene base can stay with the bottle as it is compatible in color and material with the container recycling stream. Bottles are generally made of clear material, and often from polyethylene or other clear olefin. With a PET container recyclate, the small amount of clear polyethylene may not be a serious contaminant to the recycling stream. To remove the upper polypropylene cover, one just pulls up on the lid and the top “snaps off”. The top is not vigorously attached to the base so this removal is easy.
In an embodiment, the base of the two-piece closure can be made very robust to vigorously grip the bottle, since it does not have to be removed. Indeed, the two piece embodiment may even be “permanently” attached such as with an adhesive.
Numerous other advantages and features of the invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims, and from the accompanying drawings.

DESCRIPTION OF THE FIGURES

A fuller understanding of the foregoing may be had by reference to the accompanying drawings, wherein:

FIG. 1 is an exploded perspective view of a two-piece component dispensing closure in accordance with one embodiment of the invention;

FIG. 2 is a cross sectional view of the dispensing closure of FIG. 1 shown assembled with a top lid in the opened position;

FIG. 3 is a perspective view of the dispensing closure of FIG. 1 shown assembled with the top lid in the closed position;

FIG. 4 is a side view of the dispensing closure of FIG. 1 shown assembled;

FIG. 5 is a back view of the dispensing closure of FIG. 1 shown assembled; and

FIG. 6 is a side view of the dispensing closure of FIG. 1 shown assembled with the top lid in the opened position;

FIG. 7 is a perspective view of the of the dispensing closure of FIG. 1 shown with the top lid in the opened position;

FIG. 8 is an exploded perspective view of a two-piece component dispensing closure in accordance with one embodiment of the invention; and

FIG. 9 is a cross sectional view of the dispensing closure of FIG. 8 shown assembled with a top lid in the opened position.

DESCRIPTION OF PREFERRED EMBODIMENTS

While the invention is susceptible to embodiments in many different forms, there are shown in the drawings and will be described herein, in detail, the preferred embodiments of the present invention. It should be understood, however, that the present disclosure is to be considered an exemplification of the principles of the invention and is not intended to limit the spirit or scope of the invention and/or claims of the embodiments illustrated.
Description of Closure Structure
The various features of the instant invention will now be described in conjunction with the embodiments depicted in FIGS. 1 through 7.
Referring now to FIGS. 1-3, there is shown a closure of the invention generally indicated by numeral 10. Closure 10 comprises a top lid part 14 and a separate base body part 16. Lid part 14 is attached to base part 16 using suitable attachment means, such as snap fitting threads 70/72 or screw threads 138/170 well known in the art.
Lid part 14 comprises a top 11 interconnected to an annular skirt portion 12 through a hinge structure 18, the top being moveable through open and closed positions via the hinge structure. Hinges 18 are best seen in FIG. 5. In the FIG. 5 embodiment, the hinges depicted can be described by the well known characterization of “butterfly” hinges. Other forms of hinge structure may be appropriate for the invention, The hinge structure need not be integrally formed. For example, the top 11 and the annular skirt portion 12 may be separately molded pieces joined via a “ball and socket” type hinge structure. Hinge structure joining a top moveable relative to stationary skirt is well established in the closure art. As shown in FIG. 1, the snap fitting thread 72 on the base part is an annular thread which does not circumvent the entire side periphery of annular top 40, thus leaving a channel 76 defined between a pair of flanges 78 forming the boundary of the annular thread 70. The channel 76 is further defined to accommodate for the internal portion of the hinge structure 18, especially when the hinge structure 18 is bending or flexing during movement and internal clearance is needed.
FIGS. 2, 6 and 7 depict the top 11 in the “open” position. The moveable top 11 comprises a disk-like portion 13 having an inside surface 42. An outer skirt 30 depends from surface 42. Outer skirt 30 is dimensioned to cover part of skirt portion 12 when the top is in its closed position. A pattern of ribs or knurls projects from the outside surface of outer skirt 30 to facilitate a consumer's grip on the top 11. In addition, an inner skirt 34 having an outer surface 36 depends from surface 42.
Annular skirt portion 12 of lid part 14 has an upper peripheral edge 15 from which a generally flat annular ring 19 extends radially inward. The inner circumference of annular ring 19 defines an orifice through which contents may be dispensed when the closure is in use. A substantially vertical wall 35 depends downward from the inner circumference of annular ring 19. As will be explained below, wall 35 is molded seamlessly and forms a sealing surface mating with surface 36 of skirt 34 when moveable top 11 is in its closed position. In order to assist dispensing of liquid contents, a pour lip 31 extends upward from the inner circumference of annular ring 19. Pour lip 31 has a generally arcuate form when viewed from above the closure and extends approximately 180 degrees around the inner circumference of annular ring 19. As seen in FIGS. 2, 6 and 7 pour lip 31 has a top surface 32 which reaches a maximum height above annular ring 19 at a point approximately 180 degrees from the back of the closure base. The function of the pour lip 31 is to avoid dribble of liquid contents down the side of the closure or onto the container when fluid is dispensed, especially from a freshly opened, full container. The top surface 32 of pour lip 31 is tapered downward/inward as shown and merges with vertical wall 35.
Continued reference to the figures shows a tab 69 depending from and extending downward from the lower edge of annular skirt 12. Tab 69 extends downward to a position below the lower edge of base body 16. Tab 69 is not attached to the base body 16. Tab 69 extends below the lower edge of base body 16 a distance sufficient to allow the extending portion to function as a closure orienting structure as explained further below. Typically, the extension of the tab below the lower edge of body 16 is from 0.1 inch to 1.0 inch and of the order 0.25 inch (i.e. 0.1 inch, 0.25 inch, 0.5 inch, 1.0 inch).
The structural aspects of the base body portion 16 are illustrated in FIGS. 1, 2 and 7. The base body portion comprises a skirt portion 22 depending from an annular top 40. The annular top 40 extends radially inward, terminating at an inner top perimeter 42 and extending downwardly defining an inner wall 45 and orifice 44 there-between. When the lid part is secured onto the base body, the inner wall 45 engages wall 35 of the lid part. Prior to initial opening, the orifice 44 is closed by a membrane 46 connected to the inner top perimeter through a frangible line of weakness 48. Further, a pull ring 38 (or other alternative gripping structure such as a pull tab) is attached to the membrane 46. Force applied to the pull ring causes the line of weakness to rupture, allowing removal of the membrane to dispense the contents of the package. It is noted that in the embodiments of FIGS. 1 through 7, the effective diameter associated with the frangible line is less than that of vertical wall 35. This arrangement permits facile removal of the membrane without need to remove top lid part 14.
The base body 16 also comprises suitable container engaging structure (not shown) positioned on the interior of skirt 22 to achieve attachment of the closure to complimentary structure on the exterior of a container neck Container engaging structures are taught in the parent applications incorporated by reference. Alternatively, well known structure such as screw threads or adhesives may be employed to achieve attachment in certain applications. It is noted that in preferred embodiments the base body member need not ever be removed from the container by the consumer. Thus, the attachment may be very robust and characterized as “permanent” (i.e. difficult to separate without extra-ordinary effort). Thus, a “permanent” attachment is one designed to prevent component separation during normal use of the product.
Closure Manufacture
The closure 10 is normally manufactured as two parts. A first part is the lid part 14. This part may be manufactured using well established injection molding. One may use polypropylene which is often the most suitable material for producing parts incorporating the living hinge structures envisioned.
A second part is the base body 16. This part may be formed using techniques such as injection or compression molding. A preferred material for forming the base body 16 is polyethylene, since this material has mechanical properties eminently suitable for creating a tear out membrane having a frangible tear line. The base body 16 may preferably be formed from “natural” material (i.e. no colorant) since it is envisioned that its removal would be unnecessary for proper recycling.
The final closure is created by combining the two separate pieces together. This joining may be achieved in a number of ways. One preferred method is to incorporate complimentary structure on each part to allow a snap combination.
Closure Application to Container
Containers may incorporate a structural feature which allows them to be oriented relative to a stream of closures. Such features include handles, exterior geometries or “spotting” indentations positioned on the bottom of the container. In the case of the instant invention, the tab 69 also may serve as an orientation feature for the closure relative to the bottle. This is accomplished by having the portion of tab 69 extending below the lower edge of skirt 22 of base body part 16 be positioned in a slot extending in the length dimension of a closure feed chute. As the oriented container passes by the closure feed chute, the container and closure are both oriented relative to each other. In a preferred application method, a simple snap-on application of the closure to the bottle maintains this desired relative orientation. It is noted however that other application approaches, such as screw on application, may be employed using other suitable orientation techniques. In this way the moveable top 11 and pour lip 31 have a desirable orientation relative to a container feature such as a handle.
Consumer Use
In use, the filled container with closure 10 applied is distributed and used as follows. Upon purchase, the integrity of the package is ensured by the presence of the tear out membrane and the fact that the base body part 16 can be robustly attached to the container in that it does not have to ever be removed. These aspects provide excellent tamper evidencing. When the consumer first opens the package, he maneuvers the top portion 11 to the open position to expose pull ring 38. He then pulls on ring 38 to remove the membrane which initially closed the dispensing orifice. The consumer then dispenses the desired amount of product and is then able to reseal the package by moving the top portion to its closed position. In the closed position, the outer surface 36 of inner skirt 34 forms a seal with vertical wall 35.
The dispensing process is repeated until the contents of the package are exhausted. At that point the package is prepared for recycling. The consumer first removes the lid part 14 which may be colored and comprise a material having contaminant characteristics relative to the major recycling product stream. In a preferred embodiment, the lid part 14 may be removed by simply pulling up on either the top 11 or the tab 69 breaking frangible line(s) 80 extending from a point vicinal a lower edge of the lid skirt to about the hinge structure such that a pulling force applied to the top or tab will be transmitted to the line of weakness of the lid skirt to cause material separation thereof and enable removal of the top from the container. This removal is especially appropriate when the lid part 14 is attached to the base body part 16 through a snap fitting. The base body part 16 is robustly attached to the container itself, but need not be removed since it comprises material compatible with the recycling material stream. Furthermore, in a preferred embodiment the base body part 16 is formed of natural material (no colorant) and therefore does not contribute a contaminating color to the recycling stream.
Referring now to FIGS. 8 and 9, in one embodiment of the invention there is provided a closure 100 for a container (not shown) having a container opening. The closure 100 includes a lower separable component closure piece 110 and an upper separable component closure piece 150, which are secured to one another via an attachment means 105.
The lower component closure piece 110 includes a base body 112 having internal engaging structure 114 adapted for engaging retention with the container adjacent the container opening. The base body 112 has a base top portion 116 and a base skirt 118 depending from a peripheral edge 120 of the base top portion 116. A removable membrane 122 is joined to a section 124 of the top portion 116 through a frangible line of weakness 126. The membrane 122 seals an area of the base body 112 adjacent the container opening and defines an orifice 130 through which contents of the container may be dispensed when the membrane 122 is removed. Removal of the membrane 122 is achieved by providing a gripping structure 144 such as a pull-ring attached to the membrane 122 at a position vicinal the inner edge of the frangible line 126.
The base body 112 further has an annular top 132 extending upwardly from the base top portion 116 and enclosing the orifice 130 therethrough. The annular top 132 has a first attachment means 134 (which is part of the attachment means 105) positioned on an external surface 136 thereof. The first attachment means 134 may in some instances be defined as a screw thread 138 extending outwardly from the outer periphery of the annular top 132. The thread 138 does not circumvent the entire annular top 132, thus leaving a channel 140 defined between a pair of flanges 142 which start the thread 138. The flanges 142 and channel 140 aid in the automatic machine securing of the lower separable component closure piece 110 to the upper separable component closure piece 150.
The upper component closure piece 150 is defined to include a lid body 152 having a top 154 attached to a lid skirt 156 through a hinge structure 158 allowing movement of the top 154 between closed and opened positions. The lid skirt 156 depends from an upper top portion 160 that extends inwardly to an inner skirt 162 that depends from an inside perimeter edge 164. The inner skirt 162 is adapted to engage an internal surface 146 of the annular ring 136 when the upper component closure piece 150 is secured to the lower component closure piece 110.
The lid body 152 includes an inner top skirt 166 defining an inner surface that engages the inner skirt 162 when the top 154 is in the closed position. The lid body 152 further has a second attachment means, such as a screw thread, 170 positioned on an internal surface of the lid skirt 156 and adapted to engage the first attachment means 138 on the base body 112 such that when the first and second attachment means are engaged the lower and upper separable component closure pieces 110 and 150 are secured to one another. And the lid body 152 further has the lid skirt 156 being formed with at least one line of weakness 172 extending from a point vicinal a lower edge of the lid skirt 156 to said hinge structure 158 such that a pulling force applied to the top 154 will be transmitted to the line of weakness 172 of the lid skirt to cause material separation thereof and enable removal of the top 154 from the container.
In other aspects of the embodiment, the removable membrane 122 is removable without removal of the upper component closure piece 150 from engaging retention with the lower component closure piece 110. In yet other aspects, the lid body 152 further comprises a tab 180 depending downward from the lid skirt 156 below the hinge structure 158 and extending a distance below the base skirt 118. The distance below the base skirt is of the order 0.25 inches. In other aspects of the embodiment, the base body 112 or at least a portion of the base body is made from a material different from a material forming the lid body 152 or at least a portion of the lid body. And yet in other aspects of the embodiment, the lid body 152 or at least a portion of the lid body has a different color than the base body 112 or at least a portion of the base body.
From the foregoing and as mentioned above, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the novel concept of the invention. It is to be understood that no limitation with respect to the specific methods and apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims.

Claims

1. A closure for a container having a container opening, said closure comprising:

lower and upper component closure pieces secured to one another, wherein, the lower component closure piece includes:

a base body having (a) internal engaging structure adapted for engaging retention with said container adjacent said container opening, (b) a removable membrane joined to a top portion of the base body through a frangible line of weakness, said membrane sealing an area of said base body adjacent said container opening and defining an orifice through which contents of said container may be dispensed when said membrane is removed, and (c) an upwardly extending annular top having a first attachment means positioned on an external surface thereof; and

the upper component closure piece includes:

a lid body having (a) a top having a downwardly depending outer skirt, said top being interconnected to a downwardly extending lid skirt through a hinge structure allowing movement of the top between closed and opened positions, (b) a second attachment means positioned on an internal surface of the lid skirt adapted to engage the first attachment means on the base body such that when the first and second attachment means are engaged the lower and upper separable component closure pieces are secured to one another, (c) an annular ring disposed inward of said outer skirt, the annular ring having an exterior wall surface adapted to engage an internal surface of said base body annular top when the upper component closure piece is secured to the lower component closure piece, and (d) an inner skirt downwardly depending from an inside surface of said top adapted to engage a portion of an interior wall surface of said annular ring when the top is in the closed position, and said lid body further having at least one line of weakness extending from a point vicinal a lower edge of said lid skirt to said hinge structure such that a pulling force applied to said top will be transmitted to said line of weakness of said lid skirt to cause material separation thereof and enable removal of said top from said container.

2. The closure of claim 1, wherein said internal engaging structure of said base body provides a permanent attachment of the lower component closure piece to the container.

3. The closure of claim 1, wherein said lid body further comprises a tab depending downward from said lid skirt and extending a distance below said base body.

4. The closure of claim 3, wherein said distance below said base body is from 0.1 inch to 1.0 inch.

5. The closure of claim 4, wherein said distance below the base skirt is of the order 0.25 inches.

6. The closure of claim 1, wherein when the top is in an open position the annular ring defines an opening, said opening being sized to permit removal of said removable membrane without separation of said upper component closure piece from said lower component closure piece.

7. The closure of claim 1 further comprising gripping structure attached to said membrane to allow facile removal of said membrane.

8. The closure of claim 8, wherein said gripping structure comprises a pull-ring attached to said membrane at a position vicinal an inner edge of said frangible line.

9. The closure of claim 1, wherein at least a portion of said lid body comprises a material different from a material forming at least a portion of said base body.

10. The closure of claim 8, wherein the hinge structure of said lid body is made of polypropylene and the removable membrane of said base body is made of polyethylene.

11. The closure of claim 1 further comprising a pour lip extending upward from an inner circumference of said annular top.

12. The closure of claim 11 wherein said pour lip has a generally arcuate form when viewed from above the closure and extends approximately 180 degrees around the inner circumference of said annular top.

13. The closure of claim 11 wherein said pour lip has a top surface which reaches a maximum height above said annular top at a point approximately 180 degrees from said hinge structure of said base body.

14. The closure of claim 13 wherein said top surface of said pour lip is tapered downward and inward and merges with said interior wall surface of said annular ring.

15. The closure of claim 1, wherein said at least a portion of said lid body has a different color than at least a portion of said base body.

16. The closure of claim 1, wherein said first and second attachment means are complementary snap fitting threads providing a snap fit engagement of the lid body and base body.

17. The closure of claim 1, wherein said first and second attachment means are complementary screw threads providing a screw engagement of the lid body and base body.