US3231078A

US3231078A - Easy open container with reclosure

Info

Publication number: US3231078A
Application number: US161535A
Authority: US
Inventors: Balocca Alfred Edward; Groves James Hampton
Original assignee: American Can Co
Current assignee: Primerica Inc
Priority date: 1961-12-22
Filing date: 1961-12-22
Publication date: 1966-01-25
Anticipated expiration: 1983-01-25

Description

Jan. 25, 1966 occ ETAL 3,231,078

EASY OPEN CONTAINER WITH RECLOSURE Filed Dec. 22, 1961 INVENTORS /4 AL mm fan 4w fl/MflZ'C/I fgyis HAM/ 70 Maris A TTOR/Vf Y United States Patent Jersey Filed Dec. 22, 1961, Ser. No. 161,535 2 Claims. (Cl. 296-46) This invention relates to hermetically sealed containers having easy open and reclosure features and to a method for making the same containers. Specifically, it pertains to a container forgas generating products having a closure construction especially adapted to provide hermeticity for the product stored therein but which may be easily opened to provide access to the product and thereafter replaced as a reclosure.

()ontainers specially constructed for containing gas generating products are well known in the art. They enjoy wide utility for both pressure and vacuum packing a great variety of such products. Generall these containers are well built with closure and seam constructions admirably suited to withstand the internal pressures gencrated by the contents and the pressure differential acting on the closure due to the conditions of packing. The numerous types of metal cans for packing roasted ground coffee are typical of these containers. Although these containers possess exceptional preserving and strength characteristics, all have a common disadvantage. That is the fact that a tear strip, either formed integrally, welded or otherwise formed as an intricate part of the end seam structure, is required to open the container. Tear strips do not provide as easy a means for opening a container as desired, since they are troublesome to operate and at times have been known to break or function improperly. Moreover, in those tear strip containers Where the end closure doubles as a reclosure, the closure and seam structure is somewhat complex and therefore presents an additional disadvantage of a more costly container.

An important object, therefore, of the present invention is to provide a container for gas generating products which is simple in construction and easy to open.

Another object of this invention is to provide a container for gas generating products which is adapted to be hermetically sealed but which may be easily opened for access to the product and thereafter reclosed.

Another object of this invention is to provide a container for gas generating products to be hermetically sealed with a closure adapted to withstand mild internal gas pressure but which may be easily removed for access to the product and thereafter repiaced as a reclosure.

A further object of this invention is to provide a method for making a hermetically sealed container for gas generating products, which is simple in construction and easy to open.

Still another object of this invention is to provide a method for making a container hermetically sealed with a closure which is adapted to withstand mild internal gas pressure but which may be easily removed for access to the product and thereafter replaced as a reclosure.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

3,231,078 Patented Jan. 25, 1966 "ice It has been found that these objects may be accomplished by providing a tubular container body and a skirted closure adapted to sealingly engage an end of the body, placing a skirted membrane of gas impermeable material interiorly of the closure, applying an adhesive to the interior of the membrane skirt, pressing the closure frictionally onto the end of the body so that the membrane conforms to the end of the body and is adhesively scaled over the peripheral wall of the body adjacent the end, and securing the skirted closure to the body with a strip of shear resistant tape wound peripherally about the closure skirt and adjacent body wall.

Referring to the drawings:

FIGURE 1 is a perspective view of a container made in accordance with the invention;

FIG. 2 is an exploded sectional view showing parts of the container of FIG. 1 in an attitude immediately prior to assembly; and

FIG. 3 is a sectional view taken substantially along lines 3-3 of FIG. 1 showing the parts of the container in assembled relation.

As a preferred or exemplary form of the invention, PEG. 1 illustrates a contained Iii having a tubular body 11 and a closure 12 assembled to one end of the body. In accordance with customary practice, the other end of the container is left open and shipped in this form to the packer along with a metal end which is double seamed to the container after the contents have been placed therein. requiring a container specifically adapted to'maintain effective hermetic protection of the contents and withstand the pressure differential acting on the closure and seam construction as a result of the conditions of packing. For example in the case of a product packed under pressure, the container must be constructed to maintain hermeticity and withstand the internal pressure which tends to build up due to gases generated by the product during storage. Roasted ground coffee is typical of such a product, but it will be understood that the container may be used to package other products. as well, whether pressure, vacuum, or atmospherically packed.

FIGURE 2 illustrates the components of container iii. in an attitude preparatory to final assembly. In the form shown, body 11 is rolled at its end into an inwardly projccting open curl 1d defining a rounded lip extending about the entire periphery of the end of the body. Spaced from curl 13 is an outwardly projecting peripheral head 14 which may be rolled or otherwise formed in the wall of body 11 a predetermined distance from curl 13. Preferably, the outermost wall of head 14 is flat and presents a smooth fiat exterior surface which coincides substantially with the exterior surface of closure 12 when as sembledto the container body. However, it will be understood that the end of body 11 may be necked-in to accommodate the closure, in which case the wall of the body below the necked-in portion is of a continuous and uniform diameter. In all other respects, body 11 is -sirni lar to any other conventional metal can body.

Closure 12 is in the form of a cup-shaped slip cover having a depending peripheral skirt 15 integral with a generally planar central panel 16. The interior diameter of the skirt is slightly greater than the exterior diameter of body 11 and has an exterior diameter substantially the same as the head 14 of the body. This ensures that the closure fits snugly over the end of the body with the skirt of the closure forming a more or less flush surface The contents may be any gas generating product.

with the bead 14 or, where the body is necked-in, as hereinbefore mentioned, with the body wall generally. At the juncture of skirt 15 and panel 16 is an annular groove 17 formed to conform substantially to the exterior contour of curl 13. The interior radius of gIOOW: 17 may be slightly larger than the radius of curl 13 for reasons to be hereinafter explained. An outwardly projecting annular bead 18 may be formed in skirt 15 as a finger grip to facilitate handling the closure, if desired.

A thin membrane or liner 30 is shown inserted within the cup-shaped closure 12. Preferably, the liner is of a gas impermeable material, such as metal foil or plastic. This liner conforms substantially to the interior contour of the closure and includes a skirt portion 31 which terminates just short of the end of skirt 15 of the closure. Liner 30 may be placed within the closure in any desired manner, but it is preferred that it be drawn into the closure at the time the closure itself is being formed. This is considered a simpler operation than forming the liner separately and ensures good conformity to the contour of the closure 12.

An adhesive 32 is applied to the inner surface of the skirt portion 31 of the liner. A variety of hot melt, thermosetting, and thermoplastic adhesives are admirably suited for bonding liner 30 to the end of the container body. Preferably, a curable adhesive, such as a vinyl resin plastisol, is used for this purpose and is applied as a thin film around the interior of the liner skirt. As hereinbefore mentioned the groove 17 in the closure may be formed slightly oversized with respect to curl 13 on the end of the body so that the adhesive has room to spread over a substantial portion of the curl and adjacent body Wall to ensure an effective seal.

The assembled closure and liner are then pressed onto the end of the container body, as is illustrated in FIG. 3. Liner 30 is thus tightly pressed against curl 13 and the adjacent wall surface of body 11, with adhesive 32 being spread over a substantial portion of the curl and adjacent wall surface. Where the adhesive .32 is a plastisol as hereinbefore mentioned, curing may. be accomplished by heating the plastisol to a temperature of 350 F. for a period of approximately three minutes to firmly seal the liner to the container body. Thus, liner 30 in effect becomes an inner closure or frangible membrane which remains sealed to the container body when closure 12 is removed and is readily rupturable to provide access to the contents of the container.

Closure 12 is secured to body 11 by a band of adhesive tape 33. Preferably this tape is wound completely around the container to overlap a portion of closure skirt 15 and the flat surface of peripheral bead 14 in the body wall. Where the product is gas generating and particularly when pressure packed, the build up of pressure within a container during storage Will distend liner 30 and tend to force the closure off. Accordingly, tape 33 and the adhesive thereon must have the characteristics to hold the closure on against the force of this internal gas pressure. For this purpose, the tape itself must have a reasonably high tensile strength, both longitudinally and transversely, to enable it to be readily removed by the consumer without breaking and to withstand blow-off pressure. The adhesive bonding the tape to the container must also have high shear strength to resist blow-off pressure while at the same time possessing low peel strength to enable its easy removal from the container. A variety of hot melt and thermosetting adhesives are admirably suited for this purpose.

As an alternative to adhesive tape 33, wide circumferential bands of shrinkable plastic can be used to seal the closure to the container body. In this case, frictional resistance of the plastic band shrunken tightly about skirt 15 and head 14 would be in excess of the force tending to lift the closure 12 off the container body. In either case, it will be understood that the tape or band 33 must be of sufficient width and cover enough of the respective surfaces of the closure skirt and body wall to afford the necessary resistance to relative movement of these surfaces. If desired, the tape may be sufliciently wide to extend from below bead 14 in the body wall to above head 18 in the closure, thereby providing Wide locking engagement over a greater surface. As well as effec tively sealing the closure to the container, the tape or band provides a continuous surface surrounding the joint between the closure and body, thus giving the end of the container a neat and smooth appearance. It will be readily appreciated that the ease by which tape 33 may be removed by the consumer is far greater than that of metal tear strip containers and that the only tools needed, if any, would be for initiating peeling of the tape and rupturing the liner.

When the tape or band 33 is removed by the consumer, the gas pressure inside the container tends to lift closure 12 and thus facilitates its easy removal. As mentioned hereinbefore, membrane 30 remains tightly sealed to the end of the container and is easily ruptured to provide access to the contents. Closure 12 may thereafter be replaced as a reclosure to preserve the freshness of the contents until completely consumed. Thus, there is provided a container construction well suited for hermetically packing gas generating products and which alfords easy opening as well as a reclosure feature for preserving the freshness of the con-tents far beyond the time of initial use.

Although the invention has been described in COIIH8C tion for gas generating products, it will be understood that its utility will apply as well to inert products, whether pressure, vacuum or atmospherically packed. In the packing of those products where blow off pressure is not a serious problem, it will be understood that the tape 33 need not be applied necessarily in continuous encircling engagement with the container but may be applied in short spaced strips about the periphery or, if desired, as one or more strips extending over the cover and longitudinally of the container body.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction and arrangement of parts and that changes may be made in the steps of the method described and their order of accomplishment without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

We claim:

1. A package comprising:

a tubular container having at one end thereof a substantially straight body wall portion terminating in a curl which circumscribes a container opening; gas-producing contents within said tubular container;

a gas-impervious inner liner adhesively affixed to said container straight body Wall portion and curl to hermetically seal said container opening;

a closure having a peripheral groove overlying and substantially conforming to said curl and a depressed central panel adapted to depress into said container opening the portion of the inner liner beneath said central panel;

said closure also including a skirt integralwith and depending from said peripheral groove in spaced juxtaposition to said straight body wall portion; and

an encircling sealing band attached to said container and said closure skirt sealing said closure to said container and positioning said closure with said central panel depressing said inner liner into said container opening;

said sealing band being manually removable whereupon the gas produced by said contents forces said depressed inner liner out of said container opening thus lifting said closure to facilitate easy removal thereof.

5 2. A package as defined in claim 1 but further characterized by an enlarged container body wall portion a djacent said straight body wall port-ion and substantially congruent to said closure skirt, said sealing band being attached between said skirt and said enlarged body Wall portion.

References Cited by the Examiner UNITED STATES PATENTS 6 Kielberg 220-53 Joyce 20652 Young 220-27 Fink 220-42 So-cke 220-29 Douty 215-38 Kenney 220-53 THERON E. CONDON, Primary Examiner.

EARLE J. DRUMMOND, Examiner.

Claims

1. A PACKAGE COMPRISING: A TUBULAR CONTAINER HAVING AT ONE END THEROF A SUBSTANTIALLY STRAIGHT BODY WALL PORTION TERMINATING IN A CURL WHICH CIRCUMSCRIBES A CONTAINER OPENING; GAS-PRODUCING CONTENTS WITHIN SAID TUBULAR CONTAINER; A GAS-IMPERVIOUS INNER LINER ADHESIVELY AFFIXED TO SAID CONTAINER STRAIGHT BODY WALL PORTION AND CURL TO HERMETICALLY SEAL SAID CONTAINER OPENING; A CLOSURE HAVING A PERIPHERAL GROOVE OVERLYING AND SUBSTANTIALLY CONFORMING TO SAID CURL AND A DEPRESSED CENTRAL PANEL ADAPTED TO DRPRESS INTO SAID CONTAINER OPENING THE PORTION OF THE INNER LINER BENEATH SAID CENTRAL PANEL; SAID CLOSURE ALSO INCLUDING A SKIRT INTEGRAL WITH SAID DEPENDING FROM SAID PERIPHERAL GROOVE IN SPACED JUXTAPOSITION TO SAID STRAIGHT BODY WALL PORTION; AND AN ENCRICLING SEALING BAND ATTACHED TO SAID CONTAINER AND SAID CLOSURE SKIRT SEALING SAID CLOSURE TO SAID CONTAINER AND POSITIONING SAID CLOSURE WITH SAID CENTRAL PANEL DEPRESSING SAID INNER LINER INTO SAID CONTAINER OPENING; SAID SEALING BAND BEING MANUALLY REMOVABLE WHEREUPON THE GAS PRODUCED BY SAID CONTENTS FORCES SAID DEPRESSED INNER LINER OUT OF SAID CONTAINER OPENING THUS LIFTING SAID CLOSURE TO FACILITATE EASY REMOVAL THEREOF.