Multi-piece flat top container

Abstract: A multi-piece flat top container includes a thermoplastic coated paperboard body 10 of a predetermined cross-sectional configuration, a thermoplastic adapter ring 14 having an annular recess 16 formed therein for mounting over the top edge of the body 10 and fusion sealed thereto, and a tamper-evident flat membrane 20 of any suitable material sealed adjacent its peripheral edge to the top edge of the adapter ring 14. An optional over-cap 26 may be mounted over the membrane 20 and adapter ring 14 without being sealed thereto.

Description: TECHNICAL FIELD This invention relates generally to containers and more particularly, to sealed multi-piece flat top containers for spoonable food products. BACKGROUND ART Heretofore, there have been a multiplicity of multi-piece flat top containers. For example: The preamble of claim 1 is based on Scanga et al patent US-A 4,094,460 (&FR-A-2 349 510) which discloses the broad idea of placing a sealing ring about the top of a container, with a foil membrane secured to the top surface of the ring by a peelable coating and permanently secured to the undersurface of an overcap. The sealing ring is heat sealed to an inner foil layer of the container. Rutkowski patent US,A,2,257,919 includes a sheet metal ring having an inner wall portion, an outer wall portion, with an intermediate pocket for mounting on the top edge of a container. A sheet metal closure or cover is adapted to mount on the upper edge seat of the ring, confining an optional packing disk therebetween. Whitney patent US,A,3,445,024 discloses a flexible sealing ring or gasket adapted to engage the top beaded edge of a glass container to seal same when covered by a cover member. Strouse et al patent US,A,3,396,899 includes a liner comprising a panel spanning the mouth of a container, with an annular flange having an inner wall, an outer wall, and an upper hot melt engaging section. A closure flange mounts on the latter section with a suitable adhesive therebetween. Johnson et al patent US,A,3,892,351 has a membrane type closure sealed by a seam to the top rolled-over edge of a round container. This, in turn is covered by an overcap with inner heat deforming ribs. Edwards patent US,A,4,787,530 discloses a container having a tamper-evident lid connected thereto by an inner airtight bead arrangement, with downward projections around the outer periphery of the container, and a continuous ring affixed to the downward projections. A review of these prior art references discloses that none of them would be functional without their respective overcaps. DISCLOSURE OF THE INVENTION A general object of the invention is to provide an improved multi-piece flat top container for spoonable food products, which satisfies the requirements of the manufacturer, the producer, the consumer, and the realities of the market place. Another object of the invention is to provide a multi-piece container including a thermoplastic coated paperboard body, a thermoplastic adapter ring mounted around and secured to the top edge thereof, and a tamper evident membrane sealed to the top surface of said adapter ring. According to the present invention, there is provided a multi-piece container comprising a thermoplastic coated paperboard body of a predetermined cross-sectional configuration, a thermoplastic adapter ring of a predetermined height and having an annular recess formed therein such that it is adapted to mount over and sit upon the top edge portion of said body and having an annular seal formed between itself and the top edge portion of said body at an intermediate height zone of said recess, and also comprising a substantially flat membrane formed of any suitable material sealed adjacent its peripheral edge to the top edge of said adapter ring, characterized in that said annular seal formed between said adapter ring and said top edge portion of said body is formed only at said intermediate height zone. In order that the invention may be clearly understood and readily carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:- BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an exploded perspective view of the container embodying the invention; Figure 1A is a fragmentary perspective view of an alternate arrangement of the side seam seal of the container; Figure 2 is a perspective view of a closed container embodying the invention, and an optional overcap therefor; Figure 3 is a cross-sectional view taken along the plane of the line 3-3 of Figure 2, and looking in the direction of the arrows; and Figures 4 and 5 are alternative embodiments of the closed container. BEST MODE OF CARRYING OUT THE INVENTION Referring now to the drawings in greater detail, Figure 1 illustrates a thermoplastic coated, square cross-section paperboard container body 10, with a side seam 12, which may be either a corner seam (Figure 1), or a center seam (Figure 1A). A thermo-formed or injection molded adapter ring 14 is formed to include an annular recess 16 (Figure 3) adapted to mount over and sit upon the top edge of the body 10. The adapter ring is fusion sealed by a seal 18 at a mid height therearound to the confined outer and inner surfaces of the top edge. The recess 16 is wider at the location of the side seam 12, as is evident from Figures 1 and 1A. A tamper evident membrane 20, comprising one of a suitable transparent film or paper, shaped to fit the area encompassed by the adapter ring 14, is mounted on the top edge 22 of the adapter ring and heat sealed thereto by a seal 24 (Figure 3) by any suitable means, such as thermal, radio frequency, ultrasonic, electromagnetic, or microwave technologies. A cover member or overcap 26 (Figure 2) is optional, and may be formed of recycled material since it does not include a product contact surface. The overcap may include an inturned free edge 28 for cooperation with the peripheral area of the fusion seal 18. The overcap 26 may be used to provide mechanical protection for the membrane 20 during transportation, and to serve as a reclosure cover for the consumer. The overcap may be eliminated entirely in a multi-pack application where an overwrap provides a secondary protection. As shown in Figure 4, the container components 30 may incorporate a rectangular cross-section. Figure 5 illustrates a further container shape, namely a square bottom 32, with suitable fold lines 34 adapted to produce a round top 36, thereby requiring a round adapter ring 38, and a round membrane 40. After being filled and sealed, the membrane 20 must be punctured or peeled off by the consumer in order to provide access to the spoonable food product within the container. INDUSTRIAL APPLICABILITY It should be apparent that the invention provides an improved flat top container for spoonable food products which should satisfy the critical and perceived needs of the manufacturer, the producer, the consumer, and the realities of the market place. Along with being completely satisfactory with respect to the just-recited needs, inasmuch as aluminum foil and hot melt adhesives are not required in the structure, it is more environmentally attractive. While but three general embodiments of the invention have been shown and described, other modifications are possible within the scope of the following claims.

Claims: A multi-piece container comprising a thermoplastic coated paperboard body (10) of a predetermined cross-sectional configuration, a thermoplastic adapter ring (14) of a predetermined height and having an annular recess (16) formed therein such that it is adapted to mount over and sit upon the top edge portion of said body (10) and having an annular seal (18) formed between itself and the top edge portion of said body (10) at an intermediate height zone of said recess (16), and also comprising a substantially flat membrane (20) formed of any suitable material sealed adjacent its peripheral edge to the top edge of said adapter ring, characterized in that said annular seal (18) formed between said adapter ring (14) and said top edge portion of said body (10) is formed only at said intermediate height zone. A multi-piece container according to claim 1, wherein said annular seal (18) is effected around both the interior and exterior of said top edge portion of said body (10). A multi-piece container according to claim 1 or 2, wherein said membrane (20) is formed of a transparent film or paper. A multi-piece container according to any preceding claim, wherein said cross-sectional configuration of said body (10) is a square, a rectangle, or a combination of square at the bottom and round at the top. A multi-piece container according to any preceding claim, wherein an overcap (26) is provided to mount over said membrane (20) and said adapter ring (14) without being sealed thereto. A multi-piece container according to claim 5, wherein an inturned free edge (28) is formed on said overcap (26) for retention co-operation with a portion of said ring (14) at said intermediate height zone. A multi-piece container according to claim 1, wherein said thermoplastic coated paperboard body includes a side seam which is a corner seam or a center seam, and said recess (16) of said adapter ring (14) is formed to accommodate same.

Inventors: LISIECKI ROBERT EDWARD, LISIECKI, ROBERT EDWARD
Applicants: ELOPAK SYSTEMS, ELOPAK SYSTEMS AG
Application year: 1991
Main classification: B65D8
IPC codes: B65D5, B65D8, B65D51