US3073477A

US3073477A - Plastic container with tear-off film cover

Info

Publication number: US3073477A
Application number: US858965A
Authority: US
Inventors: Thomas E Betner
Original assignee: PLASTOMATIC CORP
Current assignee: PLASTOMATIC CORP
Priority date: 1959-12-11
Filing date: 1959-12-11
Publication date: 1963-01-15
Anticipated expiration: 1980-01-15
Also published as: DE1183430B; GB907276A

Description

Jan. 15, 1963 T. E. BETNER 3,073,477

PLASTIC CONTAINER WITH TEAR-OFF FILM COVER Filed Dec. 11, 1959 2 Sheets-Sheet 1 Jan. 15, 1963 T. E. BETNER 3,073,477

PLASTIC CONTAINER WITH TEAR-OFF FILM COVER Filed Dec. 11, 1959 2 Sheets-Sheet 2 Fig. 7

United States Patent Ofifice 3,073,477 Patented Jan. 15, 1963 Pennsylvania Filed Dec. 11, 1959, Ser. No. 858,965 3 Claims. (Cl. 22054) This invention relates to sealed plastic containers having beads or rims which are torn off for access to the container contents.

In accordance with the present invention, the tearoff bead extending around the open end of the container body has a hole, recess or gap which is bridged by a tab extending outwardly from the head. The cover of the container consists of a plastic film element peripherally sealed to the tear-off bead. By lifting the tab of the sealed container, the film cover and the tear-01f bead are together separated from the container body by a smooth tear beginning at the joinder of the tab with the bead on one side of the hole and resuming on the other side of the hole along the joinder of the bead with the upper end of the container. The opened container, minus the film cover and bead, remains intact for serving or dispensing of its contents and for other subsequent use.

The invention further resides in containers having features of construction, combination and arrangement hereinafter described and claimed.

For a more complete understanding of the invention, reference is made in the following description of an embodiment thereof to the accompanying drawings in which:

FIG. 1 is a top plan view of a container body;

FIG. 2 is a side elevational view, in section taken on line 2-2 of FIG. 1 showing the container body of FIG. 1 with the cover film sealed thereto;

FIG. 3 is an enlarged view of the upper right-hand portion of FIG. 2;

FIG. 4 is an enlarged view similar to FIG. 3 except taken at section line 4-4 of FIG. 1;

FIG. 5 is a fractional view, which on enlarged scale and in perspective, shows the tab and tear-off bead of the preceding figures;

FIG. 6 is an explanatory figure referred to in discussion of opening of the sealed container;

FIG. 7 is a top plan view of a modification of the container body of FIG. 1;

FIG. 8 is a partial side elevational view on enlarged scale and in section taken on line 88 of FIG. 7; and

FIG. 9 is similar to FIG. 8 with the cover film applied.

Referring to FIGS. 1 to 6 of the drawings, the container body 10 is a self-supporting receptacle formed, as by molding, of plastic material such as polypropylene, one of the various types of polyethylene, or the like. The open end of the body 10 is formed with an intergal outwardly extending tear-off head or rim 11 which is peripherally continuous and of substantially uniform thickness except for the hole or recess 12. The hole 12 extends through the bead between its upper and lower faces and is preferably formed during the body-molding operation rather than subsequently by a drilling or punching step.

As moulded, the body 10 is also provided with an integral tab 13 extending outwardly from the tear-off head 11. As best shown in FIGS. 1 and 5, the tab 13 is joined along one edge to the outer periphery of the head 11 on opposite sides of the hole 12. So bridging the gap or weaker portion of the head, the tab 13 effectively serves to maintain the peripheral continuity and strength of the bead. More specifically, the tapering rear portion 14 of the tab is joined to the periphery of the bead for a substantial distance from the hole 12. The forward portion of the tab is joined to the outer periphery of the bead on the opposite side of hole 12 for a substantially shorter distance and then extends freely away from the head to form a finger grip 15. The grip portion of the tab preferably has a serrated or similarly rough surface.

After the container body is filled with its intended contents, a plastic film element 16 is applied over the open end of the container body and is peripherally sealed to the upper face of the tear-off bead 11. In the vicinity of the tab, the applied film (FIGS. 2 and 3) overlies the upper end of the hole 12 and serves two purposes: (1) to provide a continuous peripheral seal for the upper end of the container; and (2) to cooperate with the tab 13 in locally reinforcing the tear-off rim in the vicinity of the gap or hole 12. As shown in FIG. 4, the cover film 16 does not extend across the outwardly widening gap between the outer periphery of the bead and the grip portion of the tab and so does not impede the bending and tearing operations later described.

With both the container body and the film cover of heat-sealing plastic, the peripheral seal between the tearoff bead 11 and the film cover 16 may be formed by application of heat and pressure by a heat-sealing die. Various suitable heat-sealing methods and arrangements are disclosed in copending applications Serial Nos. 852,- 040, 859,865, 852,026. Suitable film materials for the cover element include polyethylene, polyethylene-coated cellophane, and propylene. The film cover may be a single film of one of such materials or it may be a combination of films laminated togetherfor example, a laminate of two films respectively of polyethylene and Mylar (a polyester film produced from a polymer of ethylene glycol and terephthalic acid). The contents of the container are thus confined and protected during shipm'ent, storage and display by an inexpensive cover arrangement consisting solely of a piece of plastic film. A laminated film taking advantage of complementary characteristics of different selected film materials provides better protection than the single-ply film which is adequate for many packaging applications.

When initial access to the container contents is desired, the sealed container is opened without recourse to any tool. Upon bending or lifting the grip 15 of the tab, a tear starts at point 17 (FiGS. 1, 5 and 6) of the joint between the tab and the outer periphery of the tear-off rim and continues to the hole 12. This separates the forward or grip portion of the tab from the tear-otf bead or rim. As the tab is further lifted, the tear resumes at the point 18 of the joint between the inner periphery of the tear-off rim and the upper edge 19 of the container body. By continued lifting of the tab whose rear portion 14 remains attached to the bead, the tear progresses around the upper edge of the container body until all of the head is removed, as a split ring, together with the cover film which remains sealed to it.

In lifting of the tab toward the position shown in FIG. 6, the lifted upper edge of the broken hole initiates a tear in the cover film. This tear continues across the cover film towards the other side of the container while tearing of the bead progresses around the top of the container body from hole 12. This tearing of the cover film permits the bead to be torn oif easily and without deformation of the container body to extent forcing out some of the contents of the container. The torn-off rim and torn cover unit is incapable of use as a cover and is discarded. The body of the opened container, minus the bead 11 and cover film, remains intact with a smooth upper edge and so is suited for dispensing or serving of the container contents and also for other subsequent use.

The tapering of the rear portion 14 of the tab is for 3 economy of material and to prevent it from being used as a grip with probability that if it could be torn at all, the tab would be wholly torn off leaving the rim and cover still attached to the container body.

Referring to FIGS. 7 to 9, the container body 10A is similar to that of the preceding figures except that the hole 12A does not extend all the way through the tear-off bead 11 so to leave a thin top section 11A (FIGS. 8, 9) comparable in thickness to the cover film 16. The top surface of the tear-off bead to which the cover film is sealed is thus unbroken throughout the peripheral length of the bead. The hole 12A is preferably formed during the body-molding operation: like hole 12 of FIGS. 1 to 6, it may be of any convenient shape but should extend nearly the full width of the bead.

This thin top wall 11A of the blind hole 12A precludes possibility of leakage of the sealed container contents and yet does not appreciably diminish the ease of tearing off the bead and cover by lifting the integral tab 13 as previously described in connection with F165. 1 to 6. The forward end or grip portion 15 of the tab 13 joins the tear-off bead 11 at point 17 closely in front of the thin top wall 11A of hole 12A whereas on the other side of hole 12A, the joinder to the bead extends rearwardly for a substantial distance.

When the grip 15 of the tab is forced upwardly, a tear starts at point 17 and continues to and across the thin section 11A of the bead to the joinder of the inner periphery of the bead with the upper edge 19 of the container body. This starts a tear of the film cover 16 where sealed to the thin wall section 11A of the bead. Upon continued lifting of the tab, the tearing of the film cover continues transversely of the container and the tearing off of the bead progresses along the upper edge of the container body until all of the bead is cleanly removed, together with the torn film cover. The body of the opened container, minus the bead and cover film, remains intact with a smooth upper edge and is suited for dispensing or serving of the container contents and also for other subsequent uses.

Containers embodying the invention need not be of circular shape as shown, but may be oval, rectangular or any other desired shape with retention of the advantages of the novel tear-off rim and tab construction above described. Since the container consists only of a plastic body and a plastic film cover, it is very inexpensive and so is economically suited for a wide variety of inexpensive products including individual servings of jelly, fruit juices, cottage cheese, dessert and the like. Since the plastic body and film cover are chemically inert, pharmaceuticals, foodstuffs and the like can be inexpensively packaged without danger of contamination. Also since the plastic body and cover film may be heat-sealed to each other, the use of adhesives with consequent possibility of contamination is avoided. The cover film may be transparent for inspection and display of the contents of the sealed container and it may have printing thereon to identify the product and/ or its source at cost substantially lower than for printed molded covers. Using film of the usual heat-sealing type, the container is hermetically sealed during shipment and display. When the container contents are of nature requiring that the container be able to breathe, such characteristic can be attained by use of a cover film which has been irradiated or otherwise treated to obtain microporosity permitting passage of gas but precluding passage of moisture.

What is claimed is:

1. A sealed container comprising a plastic body having an integral tear-off bead extending outwardly about the periphery of said body at its open end, said bead having a hole which extends substantially from the outer edge of the bead to its junction with said body locally to weaken the head, a plastic film cover peripherally heatsealed to the upper face of said bead hermetically to seal the container and to reinforce the weakened bead in the vicinity of said hole, and an outwardly extending tab having its inner edge integrally joined to the outer edge of said bead on opposite sides of said hole and on one side of said hole extending beyond the joinder with said bead to provide a grip end having an outwardly widening gap to the bead and which is free of said film cover, said tab when bent at the grip end tearing away from the bead to said hole and when then lifted tearing said head and the film cover together from the container body.

2. A sealed container comprising a semi-rigid plastic body having an integral tear-off rim extending outwardly from the open end of said body, said rim being of substantially uniform cross-section throughout its length ex cept where substantially reduced by a blind hole extending substantially from the outer edge of the rim to its joinder with the container body and from the lower face of the rim nearly to the upper face thereof, a tab integrally joined along its inner edge to the outer edge of said rim on opposite sides of said hole and extending freely outwardly beyond its joinder with the rim on one side of the hole to provide a finger-grip, and a plastic film cover peripherally heat-sealed to the continuous upper face of said tear-off rim and free of attachment to said fingergrip, said grip when bent and lifted tearing the tab from the rim on said one side of said hole and then tearing the rim and tab from the container body progressively from said other side of said hole with concurrent tearing of the film toward the opposite side of the container body to remove the rim and the cover film sealed thereto.

3. A sealed container comprising a plastic container body having an integral tear-off bead extending outwardly about the periphery of said body at one end thereof, said head of the body having an integral tab extending outwardly from the outer edge thereof, said bead of the container having a hole which extends substantially from the junction of the bead with said body to the outer edge of the bead in a region intermediate the ends of the junction between the tab and the bead, and a plastic film cover peripherally sealed to the tear-off bead hermetically to seal the container and locally to reinforce the head in the vicinity of said hole, said tab when bent at one end tearing along the outer edge of said body head to said hole and when then lifted tearing said bead along the inner edge thereof from the container body and transversely tearing said film cover which remains heat-sealed to the torn-off bead so to expose said end of the container for rernoval of its contents.

References Cited in the file of this patent UNITED STATES PATENTS 2,630,238 Battershy Mar. 3, 1953 2,887,244 Betner May 19, 1959 2,941,660 Tupper June 21, 1960 FOREIGN PATENTS 1,136,987 France Jan. 7, 1957 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 3,073,,477 January 15 1963 Thomas Eu Betner It is hereby certified that error a ent requiring correction and that the sa corrected below.

ppears in the above numbered pat id Letters Patent should read as Column 2,, line 27 for "859,865" read 859 685 Signed and sealed this 10th day of December 1963,

( SEAL) Attest:

ERNEST W SWIDER Attesting Officer EDWIN L, REYNOLDS Ac ti ng Commissioner of Patents

Claims

1. A SEALED CONTAINER COMPRISING A PLASTIC BODY HAVING AN INTEGRAL TEAR-OFF BEAD EXTENDING OUTWARDLY ABOUT THE PERIPHERY OF SAID BODY AT ITS OPEN END, SAID BEAD HAVING A HOLE WHICH EXTENDS SUBSTANTIALLY FROM THE OUTER EDGE OF THE BEAD TO ITS JUNCTION WITH SAID BODY LOCALLY TO WEAKEN THE BEAD, A PLASTIC FILM COVER PERIPHERALLY HEATSEALED TO THE UPPER FACE OF SAID BEAD HERMETICALLY TO SEAL THE CONTAINER AND TO REINFORCE THE WEAKENED BEAD IN THE VICINITY OF SAID HOLE, AND AN OUTWARDLY EXTENDING TAB HAVING ITS INNER EDGE INTEGRALLY JOINED TO THE OUTER EDGE OF SAID BEAD ON OPPOSITE SIDES OF SAID HOLE AND ON ONE SIDE OF SAID HOLE EXTENDING BEYOND THE JOINDER WITH SAID BEAD TO PROVIDE A GRIP END HAVING AN OUTWARDLY WIDENING GAP TO THE BEAD AND WHICH IS FREE OF SAID FILM COVER, SAID GAP WHEN BENT AT THE GRIP END TEARING AWAY FROM THE BEAD TO SAID HOLE AND WHEN THEN LIFTED TEARING SAID BEAD AND THE FILM COVER TOGETHER FROM THE CONTAINER BODY.