US3166234A

US3166234A - Plastic container with plait formed pull tab

Info

Publication number: US3166234A
Application number: US101775A
Authority: US
Inventors: Stephen W Amberg
Original assignee: Lily Tulip Cup Corp
Current assignee: Lily Tulip Cup Corp
Priority date: 1961-04-10
Filing date: 1961-04-10
Publication date: 1965-01-19
Anticipated expiration: 1982-01-19
Also published as: DE1175599B; GB939204A

Description

Jan. 19, 1965 s. w. AMBERG 3,166,234

PLASTIC CONTAINER WITH PLAIT FORMED PULL TAB Filed April 10. 1961 INVENTOR. STEPHEN VV 14/ 75526;

Arrow/Ex:

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United States Patent O 3,166,234 v PLASTIC CONTAINER WITH PLAIT FORMED PULL TAB Stephen W.'Ambei'g, Syosset, N.Y., assignor to Lily-Tulip Cup Corporation, New York, N.Y., a corporation of Delaware 7 Filed Apr. 10,1961, Ser. No. 101,775 3 Claims. (Cl. 229-51) This invention relates to containers and, more particularly, to plastic containers assembled to constitutesanitacle has been filled with the materials to be packaged.

In such containers a relatively Weak bond is effected between the cover'and a flange or rim of the receptacle such as by forming them of mutually immiscible substances and heat sealing them to close the receptacle.

According to the prior art, the cover is removed in its entirety, and forthis purpose, in one embodiment of the prior art, the .cover, extends outwardly beyond an edge of the container to provide an outwardly extending engageable marginal portion; while in another embodiment, the flanges of the container are cut away to permit engagement of the cover. v

I have conceived a completely new and different combination embodying several advantages over the prior art including the facility of handling the filling and closing of containers, the ability to completely remove the cover by means of a readily engageable tab or handle disposed in a convenient location on top of the cover while retaining the tab attached to the cover during such removal.

As a feature of the invention, the receptacle has a peripheral flange or rim and the cover is severably secured to this rim, but the cover is foldediback upon itself to form a plait extending across the open end of the-receptacle. The plait provides a finger grip by which the cover may be grasped and torn completely away from the receptacle.

This form of plait pull tab, in addition to the advantage of being disposed in readily engageable position on top of the container, provides other substantial advantages over the prior art. To fully appreciate these advantages, it is noted that in the production of the filled individual small containers very substantial economies in time and cost are obtained where the empty containers are joined together in a gang comprising several parallel rows of containers each comprising several containers all connected together in the plane of the rim flanges to form a gang of containers which are filled in gang formation and then covered by a common sheet disposed over the gang and sealed to the flange portions; thereafter the containers are severed from the gang to provide individual filled containers. In accordance with this invention, since the pull tabs are disposed on the top of the covers, the plaits for an entire row of containers may be formed across the cover sheet and the severance of the gang into individual containers may be readily accomplished without disturbing the pull tabs. On the contrary, in the prior art (referred to supra), where the hand engageable portion of the cover is provided by extending the cover beyond the edges of the container, such gang handling is prohibited because in cutting or shearing the filled containers apart into individual containers it is not possible to leave the edge of the cover extending beyond the corre- 3,166,234 Patented Jan. 19,. 1965 ICC sponding edge of the container flange, as will be evident from Marshall Patent No. 2,736,656.

A further advantage of the invention is that the plait pull tabs of the invention lie flat against the cover and are not disturbed when the filled containers are stacked one upon the other in closely adjacent stakes; whereas in the prior art the overhanging edges are subject to distortion or even accidental rupture to the closure seal.

. As a further feature of the invention, the facing surfaces of the plait are secured together at the marginal regions thereof overlying the peripheral rim of the receptacle so that the sanitary integrity of the container is assuredwhen cover and receptacle are secured together. Preferably, this feature is achieved by providing an adhesive coating on the undersurface of the cover so that when the plaits are formed and the covers secured to the receptacle rims, as by pressure and temperature, for example, the inner surfaces of the plaits will be sealed together at those regions thereof that overlie the rims.

There has thus been outlined rather broadly the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of the invention. It is important, therefore, that the claims be regarded as includingsuch equivalent constructions as do not depart from the spirit and scope of the invention.

A specific embodiment of the invention has been chosen for purposes of illustration and description, and is shown in the accompanying drawing, forming a part of the specification, wherein:

FIG. 1 is a top plan view of a container in accordance with the present invention;

FIG. 2 is a front elevational view of the container shown in FIG. 1;

FIG. 3 is an enlargedview of a portion of the container shown in FIGS. 1 and 2; and

FIG. 4is a perspective view illustrating an embodiment of the invention showing the cover in the stage of partial removal.

Referring now to the drawings in detail, and more particularly to FIGS. 1 to 3 thereof, there is shown an individual portion container 10 comprising a receptacle 11 which is formed of a suitable plastic such as high impact polystyrene, for example. The receptacle 11 is formed with tapered side walls and is shouldered as at 12 near its upper end for rigidity and stacking purposes, and is provided with a top opening'14 (FIG. 4). A peripheral rim or flange 15 extends outwardly of the upper edges of the side walls and a cover 16 is substantially coextensive with the flange and thus overlies the opening 14 at the upper end of the receptacle. This cover 16 is removably secured to the rim 15 in a manner and for a purpose to be later described.

According to the present invention, the cover 16 is folded'back upon itself to form a plait 17 external to the receptacle and which extends across the full width of the open end of the receptacle 11 in one direction. The plait 17 thus forms a pull tab which may conveniently be grasped when it is'desired to open the container. Preferably, the cover 16 is coated on its under surface with a 3 7 while avoidingfusing of the materials and, preferably even distortion thereof. Such sealing may be effected at a temperature between 200 F. and 220 F., and prefer-' ably at approximately 210 F. for a dwell of about one second andv under a pressure of the order of 40 pounds per square inch for a single container and cover.

Since the underside of the cover is fully coated with the adhesive, it will be appreciated that as the cover is sealed to the rim 15 of the receptacle, sealing will also occur between opposed surfaces of the plait 17 itself at its marginal ends overlying the rim 15, thus to assure the complete sealing of the container.

Referring now to FIG. 4, the cover 16 is formed of a tough plasticfilm which resists tearing. It has been found that a polyester film such as polyethylene terephthalate sold by duPont under the name Mylar is eminently suitable for this purpose.

Accordingly, when the plait is grasped and pulled in the direction indicated by the arrow in FIG. 4, the cover 16 resists tearing along the plait crease lines, but rather, the adhesive seal between the cover 16 and rim or flange 15 is broken and the cover is peeled from the flange 15 whereby the cover 16 may be completely severed from the receptacle 11.

It will be understood that in the manufacture of the containers, the receptacles may be arranged conveniently in gang formation, filled, covered with a common plaited sheet as'above described, and sealed; and thereafter individual sealed containers severed from the gang.

Since the film for the cover 16 is a relatively tough material, it may be and preferably is made relatively thin for purposes of economy and to facilitate removal. For example, such material having a thickness of about .001" has been found entirely satisfactory forportion size containers, with somewhat thicker covers being desirable for containers of larger'size.

From the foregoing description, it will be seen that I have contributed an improved sanitary disposable plastic portion container having the advantages above noted.

I believe that the construction and utilization of my novel container will now be understood and that the advantages thereof will be fully appreciated by those persons skilled in the art.

What I claim is:

l. A plastic container comprising a receptacle having an integral peripheral rim both formed of a plastic and a cover overlying the open end of said receptacle and formed of a tough, tear resistant plastic, said cover being folded back upon itself along parallel crease lines to form a manually engageable plait extending across the open end of said receptacle, the lower surface of the margin of said cover being severably adhered to the upper surface of the rim of said receptacle and the facing surfaces of said plait being secured to one another at the marginal ends thereof overlying said rim, said plait extending across said receptacle to its open end including said rim flange and being free to pivot about its juncture with said cover, the folds of said plait at said pivotal juncture being substantially stronger than the severable adherence between said cover and the upper face of said rim flange, whereby a tension force exerted on said plait peels the cover from the rim flange while leaving said plait attached to said cover.

2. A plastic container comprising'a receptacle having an open end defined by a peripheral rim flange, and a receptacle cover overlying the open end of said receptacle and severably secured to the upper face of said rimflange in superimposed. relation. to form therewith a two ply laminate, one ply of which is readily peelable from the other, said cover being folded back upon itself alongv an inner fold line to form an inner foldv and along an outer fold line to form an outer fold, said inner and outer folds conjointly forming a manually engageable plait extending across said receptacle at its open end including said rim flange and being free to pivot about said inner fold line relative to said cover for the full length of said plait, the inner and outer folds of said plait adjacent said pivotal juncture being substantially stronger than the severable securing means between said cover and the upper face of said rim flange, whereby a tension force exerted on said plait peels said cover from said rim flange while leaving said plait attached to said cover.

3. A container'comprising a receptacle having an open end defined by a peripheral rim and a plastic cover therefor overlying the open end of said-receptacle and said rim, said cover being folded back upon itself along inner and outer fold lines to. form a plaitextending across the full width'of'fthe open endof said receptacle on the side i of said cover away from said receptacle so as to constitute a pull tab, the inner surface of said cover being peelably secured to the rim of said receptacle, said plait being free to pivot about said inner fold line relative to said cover for the full length of said plait, the inner and outer folds of said plait .adjacent said pivotal juncture being substantially stronger than the severable securing means between said cover and the upper face of said rim flange, whereby a tension force exerted on said plait peels said cover from said rim flange while leaving said plait attached to said cover.

References Cited in the file of this patent UNITED STATES PATENTS 2,062,278 Vogt Nov. 24, 1936 2,973,087 Rohdin Feb. 28, 1961 2,990,948 Zackheim July 4, 1961

Claims

1. A PLASTIC CONTAINER COMPRISING A RECEPTACLE HAVING AN INTEGRAL PERIPHERAL RIM BOTH FORMED OF A PLASTIC AND A COVER OVERLYING THE OPEN END OF SAID RECEPTACLE AND FORMED OF A TOUGH, TEAR RESISTANT PLASTIC, SAID COVER BEING FOLDED BACK UPON ITSELF ALONG PARALLEL CREASE LINES TO FORM A MANUALLY ENGAGEABLE PLAIT EXTENDING ACROSS THE OPEN END OF SAID RECEPTACLE, THE LOWER SURFACE OF THE MARGIN OF SAID COVER BEING SEVERABLY ADHERED TO THE UPPER SURFACE OF THE RIM OF SAID RECEPTACLE AND THE FACING SURFACES OF SAID PLAIT BEING SECURED TO ONE ANOTHER AT THE MARGINAL ENDS THEREOF OVERLYING SAID RIM, SAID PLAIT EXTENDING ACROSS SAID RECEPTACLE TO ITS OPEN END INCLUDING SAID RIM FLANGE AND BEING FREE TO PIVOT ABOUT ITS JUNCTURE WITH SAID COVER, THE FOLDS OF SAID PLAIT AT SAID PIVOTAL JUNCTURE BEING SUBSTANTIALLY STRONGER THAN THE SEVERABLE ADHERENCE BETWEEN SAID COVER AND THE UPPER FACE OF SAID RIM FLANGE, WHEREBY A TENSION FORCE EXERTED ON SAID PLAIT PEELS THE COVER FROM THE RIM FLANGE WHILE LEAVING SAID PLAIT ATTACHED TO SAID COVER.