US-12617596-B2 - Flow wrap packaging structures

US12617596B2US 12617596 B2US12617596 B2US 12617596B2US-12617596-B2

Abstract

A web of sheet material is provided which can be wrapped around a product to form a pack. The sheet material comprises a sealant ply laminated to an outer ply. The sealant ply has a first major surface and a second major surface opposite the first major surface, the first major surface comprising a heat sealable material. The outer ply has a third major surface and a fourth major surface opposite the third major surface, wherein the third major surface faces the second major surface. The web of sheet material comprises a plurality of connected blanks, each blank comprising a plurality of cutouts removing a portion of the outer ply, the cutouts aligned with overlapping portions of transverse heat seal regions of the sheet material.

Inventors

Quang T. Phung

Assignees

PROAMPAC HOLDINGS INC.

Dates

Publication Date: 20260505
Application Date: 20240315

Claims (20)

1 . A web of sheet material which can be wrapped around a product to form a pack, the sheet material comprising: a sealant ply laminated to an outer ply; the sealant ply having a first major surface and a second major surface opposite the first major surface, the first major surface comprising a heat sealable material; the outer ply having a third major surface and a fourth major surface opposite the third major surface, wherein the third major surface faces the second major surface; the web of sheet material comprising a plurality of connected blanks, each blank comprising: a first longitudinal edge extending in a machine direction; a second longitudinal edge extending in the machine direction, the second longitudinal edge opposite the first longitudinal edge; a first transverse edge extending in a transverse direction; and a second transverse edge extending in the transverse direction, the second transverse edge spaced apart from the first transverse edge in the machine direction; a first longitudinal heat seal region extending along the first longitudinal edge from the first transverse edge to the second transverse edge; a second longitudinal heat seal region extending along the second longitudinal edge from the first transverse edge to the second transverse edge, the first longitudinal heat seal region heat sealable to the second longitudinal heat seal region to form a longitudinal heat seal; a first longitudinal fold line extending from the first transverse edge to the second transverse edge, the first longitudinal fold line disposed intermediate a longitudinal center axis and the first longitudinal edge; a second longitudinal fold line extending from the first transverse edge to the second transverse edge, the second longitudinal fold line disposed intermediate the longitudinal center axis and the second longitudinal edge; a first transverse heat seal region extending along the first transverse edge from the first longitudinal edge to the second longitudinal edge, wherein a first portion of the first transverse heat seal region is configured to form a heat seal with a second portion of the first transverse heat seal region, wherein the first portion of the first transverse heat seal region faces the second portion of the first transverse heat seal region when the blank is folded along the first longitudinal fold line, and wherein a third portion of the first transverse heat seal region is configured to form a heat seal with a fourth portion of the first transverse heat seal region, wherein the third portion of the first transverse heat seal region faces the fourth portion of the first transverse heat seal region when the blank is folded along the second longitudinal fold line; a second transverse heat seal region extending along the second transverse edge from the first longitudinal edge to the second longitudinal edge, wherein a first portion of the second transverse heat seal region is configured to form a heat seal with a second portion of the second transverse heat seal region, wherein the first portion of the second transverse heat seal region faces the second portion of the second transverse heat seal region when the blank is folded along the first longitudinal fold line, and wherein a third portion of the second transverse heat seal region is configured to form a heat seal with a fourth portion of the second transverse heat seal region, wherein the third portion of the second transverse heat seal region faces the fourth portion of the second transverse heat seal region when the blank is folded along the second longitudinal fold line; a first cutout removing a portion of the outer ply aligned with the first portion of the first transverse heat seal region; a second cutout removing a portion of the outer ply aligned with the fourth portion of the first transverse heat seal region; a third cutout removing a portion of the outer ply aligned with the first portion of the second transverse heat seal region; and a fourth cutout removing a portion of the outer ply aligned with the fourth portion of the second transverse heat seal region; wherein a portion of the outer ply extends into each of the first and second longitudinal heat seal regions.
2 . The web of sheet material of claim 1 , wherein the outer ply comprises a paper layer.
3 . The web of claim 1 , further comprising: the first cutout and third cutout each extending from the first longitudinal heat seal region to a point intermediate the first longitudinal fold line and the longitudinal center axis; and the second cutout and fourth cutout each extending from the second longitudinal heat seal region to a point intermediate the second longitudinal fold line and the longitudinal center axis.
4 . The web of claim 3 , further comprising: the first cutout and third cutout each transversely extending at least partially into the first longitudinal heat seal region; and the second cutout and fourth cutout each transversely extending at least partially into the second longitudinal heat seal region.
5 . The web of claim 1 , further comprising: the first cutout and third cutout each extending from the first longitudinal heat seal region to the first longitudinal fold line; and the second and fourth cutout each extending from the second longitudinal heat seal region to the second longitudinal fold line.
6 . The web of claim 1 , further comprising: the first cutout and third cutout each transversely extending at least partially into the first longitudinal heat seal region; and the second cutout and fourth cutout each transversely extending at least partially into the second longitudinal heat seal region.
7 . The web of claim 1 , wherein a front panel is defined by the sheet material disposed between the first longitudinal fold line and the second longitudinal fold line.
8 . The web of claim 7 , wherein the front panel further comprises a window defined by a cutout in the outer ply.
9 . The web of claim 7 , wherein the front panel further comprises a window region covered by a tear-away perforated panel.
10 . The web of claim 9 , wherein the tear-away perforated panel comprises zipper-like perforations.
11 . The web of claim 1 , further comprising a plurality of perforations in the sealant ply.
12 . The web of claim 1 , wherein the sealant ply comprises an anti-fogging agent.
13 . The web of claim 12 , wherein the anti-fogging agent is applied as a coating layer on the first major surface.
14 . The web of claim 1 , further comprising: the second cutout and fourth cutout each transversely extending for entire transverse extent of the second longitudinal heat seal region, wherein the first cutout and third cutout each do not substantially extend into the first longitudinal heat seal region.
15 . A packaging blank formed of the web of claim 1 .
16 . A packaging blank formed of the web of claim 2 .
17 . A packaging blank formed of the web of claim 3 .
18 . A package formed of the web of claim 1 .
19 . A package formed of the web of claim 2 .
20 . A package formed of the web of claim 3 .

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application claims the priority benefit of U.S. Provisional Patent Application Ser. No. 63/452,593 filed Mar. 16, 2023 and U.S. Provisional Patent Application Ser. No. 63/536,005 filed Aug. 31, 2023. Each of the aforementioned applications is incorporated herein by reference in its entirety. BACKGROUND The present invention relates to packaging structures and, in particular, to flexible packaging structures suitable for products, including food products and others, that are packaged utilizing flow wrap equipment. Flexible film packages are known in the art to provide a bag or pouch for enclosing products for shipping, handling, and storage. Such packages may be formed of flow wrap type packaging which allows a continuous film to envelop the product during packaging. During the flow wrapping process, a fin seal extending in the machine direction is formed and transverse heat seals are formed at the ends. The film material is typically a plastic film, such as polyethylene or polypropylene, or a laminate such as two layers of polypropylene or a polyester (PET) laminated to a polyethylene sealant. Flexible film packages have a number of advantages over rigid containers, including lower cost, lighter weight, and smaller storage footprint. Flexible sheet materials comprising paper or film ply laminated to a polymer material are generally known in the art. Laminations comprising a paper-containing ply and a polymer ply are advantageous in that the paper provides good mechanical strength, is made from a renewable resource, can be recyclable or compostable and has good printability, while the polymer ply can impart good barrier properties and heat scalability to the structure. However, the presence of a paper outer ply requires a relatively longer scaling time to form the transverse end seals than an all plastic film material. Flow wrap equipment utilizing conventional rotary sealing heads may lack sufficient contact time with the film to transfer sufficient heat through the outer lamination to adequately melt the heat seal layers and produce an airtight seal. Similar problems may be seen with laminations comprising a non-paper outer ply where the outer ply is relatively thick or has high thermal resistance or where the heat sealing range or window is very narrow. Flow wrap equipment having long dwell sealing heads is known in the art to increase the dwell time. However, such equipment requires cam arrangements which allow the heat seal head to translate in the machine direction at the same speed as the film to extend the heating dwell time. Such systems include D-cam profile, box motion profile, oval cam profile, and so forth. While such systems provide increased heat sealing capabilities due to their ability to extend the length of time that the heat seal heads are in contact with the film, such systems also increase the complexity, cost, and footprint of the equipment. It would be desirable to provide improved film structures having a paper component or other thermally resistant component that can be used for flow wrap applications utilizing rotary sealing heads while also providing high integrity heat seals. SUMMARY In one aspect, a web of sheet material is provided which can be wrapped around a product to form a pack. The sheet material comprises a sealant ply laminated to an outer ply. The sealant ply has a first major surface and a second major surface opposite the first major surface, the first major surface comprising a heat sealable material. The outer ply has a third major surface and a fourth major surface opposite the third major surface, wherein the third major surface faces the second major surface. The web of sheet material comprises a plurality of connected blanks, each blank comprising a plurality of cutouts removing a portion of the outer ply, wherein the cutouts are aligned with overlapping portions of transverse heat seal regions of the sheet material. In a further aspect, a method of forming a pack is provided. Advantages and benefits of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments. BRIEF DESCRIPTION OF THE DRAWINGS The invention may take form in various components and arrangements of components, and in various steps and arrangements of steps. The drawings are only for purposes of illustrating preferred embodiments and are not to be construed as limiting the invention. FIG. 1 is an exploded view of an exemplary blank for producing a pack in accordance with the present disclosure. FIG. 2 is a bottom plan view of the blank appearing in FIG. 1, illustrating the first, second, third, and fourth portions of each of the first and second transverse sealing regions. FIG. 3 is a top plan view of the blank appearing in FIG. 1. FIG. 4 is a top plan view of a first embodiment blank for producing a first embodiment pack in accordance