TECHNICAL FIELD

Embodiments of the present disclosure generally relate to compositions, reclosable multilayer films that include the compositions, and reclosable packaging articles that include the compositions or the multilayer films.

BACKGROUND

Convenience is a growing trend in the food packaging industry, with consumers looking for packaging that can be easily handled and used. Reclosability in flexible packaging not only offers consumer convenience, but also provides longer shelf life of the packed product without the need to transfer contents into separate reclose packages, such as a zippered plastic bags or rigid containers with lids, for example. Conventional reclose systems are limited in availability and have shortcomings such as additional fabrication steps or poor processability. Conventional reclose packages are usually coated water based acrylics and require lamination, die-cutting, or other secondary processing steps. Hot melt adhesives based on styrenic block copolymers (SBC) eliminate some of the processing steps needed for coated adhesives, but are difficult to process and may impart an odor and/or taste to contents of the package.

SUMMARY

Accordingly, ongoing needs exist for a composition and multilayer films that include the composition that provide reclosability (reclose/reopen functionality) to packaging and that, in some embodiments, is safe for food packaging applications and does not impart an odor to the contents of the reclosable packaging. A need further exists for a composition that is extrudable to produce the multilayer films. A need further exists for a composition that provides improved bond strength upon reclosing the multilayer film while maintaining an initial bond strength low enough to enable the multilayer film to be easily opened initially to activate the reclose/reopen functionality.

One or more of these needs are met by various embodiments of the compositions of the present disclosure. The compositions may be adhesive compositions, such as extrudable pressure sensitive adhesive compositions that provide reclose/reopen functionality to multilayer films made therewith. The composition includes an ethylene/alphα-olefin random copolymer, less than 50 wt. % of a styrenic block copolymer, a tackifier, and an oil. The composition can be extruded to produce multilayer films that include the composition. The multilayer films may be included in packaging to provide reclose/reopen functionality to the packaging.

According to one or more embodiments, a composition may include (a) an ethylene/α-olefin random copolymer having density of 0.890 g/cm3 or less, a melting point of 100° C. or less, and a melt index from 0.2 g/10 min to 8.0 g/10 min; (b) a styrenic block copolymer comprising from greater than 1 wt % to less than 50 wt % units of styrene; (c) a tackifier; and (d) an oil. The composition may be an adhesive composition. The composition may exhibit an overall melt index of the composition of from 2 g/10 min to 15 g/10 min.

According to one or more other embodiments, a multilayer film may include at least 3 layers, each having opposing facial surfaces. The 3 layers of the multilayer film may include a layer A, a layer B, and a Layer C. Layer A may include a sealant layer, and Layer B may include the composition of any of the embodiments disclosed herein. A top facial surface of Layer B may be in adhering contact with a bottom facial surface of Layer A. Layer C may include a polyolefin, and a top facial surface of Layer C may be in adhering contact with a bottom facial surface of Layer B. In some embodiments, an article may include the compositions of any other embodiments of the present disclosure. The articles may further include the multilayer films of any other embodiments of the present disclosure.

According to yet other embodiments, a package includes a substrate and a multilayer film that includes at least 3 layers, each layer having opposing facial surfaces. A Layer A comprises a sealant layer. A Layer B may include a composition comprising an ethylene/α-olefin random copolymer having a density less than or equal to 0.890 g/cm3, a melting point of less than or equal to 100° C., and a melt index of from 0.2 g/10 min to 8.0 g/10 min; a styrenic block copolymer comprising from greater than 1 wt. % to less than 50 wt. % units of styrene; a tackifier; and an oil. A Layer C may include a polyolefin or a sealant. A top facial surface of Layer B may be in adhering contact with a bottom facial surface of Layer A, and a top facial surface of Layer C may be in adhering contact with a bottom facial surface of Layer B. The package may include at least one sealing region in which at least a portion of a top facial surface of Layer A is in adhering contact with at least one surface of the substrate to form a seal between the multilayer film and the substrate.

Additional features and advantages of the described embodiments will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the described embodiments, including the detailed description which follows, the claims, as well as the appended drawings.

