Coextruded multilayer sheet and sleeve label for bottles

A coextruded multilayer sheet adapted to form a label sleeve for containers,

• a polystyrene foam layer adapted to be inside the sleeve adjacent a container and an outer skin layer adapted for printing or decorating comprising solid skin formed by extruding a blend of about 5 to 50% by wt. of a polyolefin;
• about 15 to 25 wt. % polystyrene and an effective amount of a compatibility agent to provide compatibility and a limited amount of adhesion at an interface between the skin and the foam layer sufficient to provide the label with toughness, sealability, and good seal strength, the compatibility agent comprising a block copolymer of styrene and butadiene, the polyolefin providing the skin layer with a shrinkage rate and limited shrinkage so the label can be heat shrunk on a container without wrinkles.

A coextruded multilayer sheet adapted for use as a solvent seal label sleeve on containers, the sleeve also being sealable by ultrasonic, hot air and heat sealing, the sheet label comprising a foam polystyrene layer for use on the inside of the sleeve next to the container and an outer skin layer formed by extruding a blend of a polymer that is a polyolefin having alkylene moieties with 2 to 4 carbon atoms, polystyrene and a compatibility agent having compatibility enhancing groups for the alkylene moieties, the compatibility agent being used in an effective amount to provide limited compatibility and limited adhesion between the skin layer and the foam layer at the interface, thereof, to enhance the toughness of the label, the amount of alkylene moieties being an effective amount to provide the skin layer with a shrinkage rate that matches the shrinkage rate of the foam layer when external heat is applied to skin layer of the label to prevent undesirable wrinkles in the outer surface of the skin layer, the amount of alkylene moieties also being effective to provide a shrinkage force of the skin layer when its outer surface is heated that is not sufficient to form wrinkles on the underside of the foam.

A coextruded multilayer sheet adapted for use as a heat shrunk label sleeve on containers, the sheet label comprising a foam polystyrene layer for use on the inside of the sleeve next to the container and an outer skin layer formed by extruding a blend of a polyethylene having alkylene moieties with 2 carbon atoms, polystyrene and a compatibility agent having compatibility enhancing groups for the alkylene moieties, the compatibility agent being used in an effective amount to provide limited compatibility and limited adhesion between the skin layer and the foam layer at the interface, thereof, to enhance the toughness of the label, the amount of alkylene moieties being an effective amount to provide the skin layer with a shrinkage rate that matches the shrinkage rate of the foam layer when external heat is applied to skin layer of the label to prevent undesirable wrinkles in the outer surface of the skin layer, the amount of alkylene moieties also being effective to provide a shrinkage force of the skin layer when its outer surface is heated that is not sufficient to form wrinkles on the underside of the foam.

A coextruded multilayer sheet adapted for use as a solvent seal label sleeve on containers, the sleeve also being sealable by ultrasonic, hot air and heat sealing, the sheet label comprising a foam polystyrene layer for use on the inside of the sleeve next to the containers and an outer skin layer formed by extruding a blend of (1) a polymer having alkylene moieties with 2 to 4 carbon atoms and compatibility enhancing groups for the alkylene moieties, and (2) polystyrene and the compatibility enhancing groups being used in an effective amount to provide limited compatibility and limited adhesion between the skin layer and the foam layer at the interface, thereof, to enhance the toughness of the label, the amount of alkylene moieties being an effective amount to provide the skin layer with a shrinkage rate that matches the shrinkage rate of the foam layer when external heat is applied to the skin layer of the label to prevent undesirable wrinkles in the outer surface of the skin layer, the amount of alkylene moieties also being effective to provide a shrinkage force of the skin layer when its outer surface is heated that is not sufficient to form wrinkles on the underside of the foam.

A container and a sheet sleeve label therefor, the sheet label comprising a foam polystyrene layer for use on the inside of the sleeve next to the container and an outer skin layer formed by extruding a blend of a polyolefin, polystyrene and a compatibility agent, the compatibility agent being used in an effective amount to provide limited compatibility and limited adhesion between the skin layer and the foam layer at the interface, thereof, to enhance the toughness of the label, the amount of polyolefin being an effective amount to provide the skin layer with a shrinkage rate that matches the shrinkage rate of the foam layer when external heat is applied to skin layer of the label to prevent undesirable wrinkles in the outer surface of the skin layer, the amount of polyolefin also being effective to provide a shrinkage force of the skin layer when its outer surface is heated that is not sufficient to form wrinkles on the underside of the foam.