Formable films, laminate structures, and related methods

A blister package for packaging a product, the blister package comprising:

• a lid layer comprising a strain-hardened aluminum foil and a lacquer layer on a sealing surface of the strain-hardened aluminum foil;
• and
• a laminate structure sealed directly to the lacquer layer, the laminate structure comprising:
• a multilayer film and a plurality of wells formed therethrough, wherein the multilayer film comprises:
• a first formable layer comprising biaxially-oriented PET having a metaphase evidenced by a metaphase transition at about 180° C. to about 200° C. as measured by differential scanning calorimetry (DSC) upon a first heating;
• and
• a sealing layer comprising a copolyester material, the sealing layer overlying the first formable layer and comprising an outer surface opposite the first formable layer, wherein the sealing layer has a crystallinity from 10% to 20% as measured by DSC, wherein the outer surface of the sealing layer is sealed directly to the lacquer layer;
• a core structure comprising a first PET layer, a second PET layer, and a silica-containing PET layer interposed between the first PET layer and the second PET layer, wherein at least one layer of the core structure has a metaphase transition at about 180° C. to about 200° C. as measured by differential scanning calorimetry (DSC) upon a first heating and has a molded volume of greater than or equal to about 200%;
• and
• an intermediate layer comprising a soft metal foil interposed between the multilayer film and the core structure.

A method for preparing a blister package, the method comprising:

• laminating a lid layer and a multilayer laminate structure under heat and pressure to form the blister package, the lid layer comprising a strain-hardened aluminum foil having a lacquer layer on a sealing surface of the strain-hardened aluminum foil, the laminate structure comprising:
• a multilayer film comprising:
• a first formable layer comprising-a thermoplastic material biaxially-oriented PET having a metaphase evidenced by a metaphase transition at about 180° C. to about 200° C. as measured by differential scanning calorimetry (DSC) upon a first heating;
• and
• a sealing layer comprising a copolyester material, the sealing layer overlying the first formable layer and having an outer surface opposite the first formable layer, the sealing layer having a crystallinity from 5% to 20% 10% to 20% as measured by DSC;
• a core structure comprising a first PET layer, a second PET layer, and a silica-containing PET layer interposed between the first PET layer and the second PET layer, wherein at least one layer of the core structure has a metaphase transition at about 180° C. to about 200° C. as measured by differential scanning calorimetry (DSC) upon a first heating and has a molded volume of greater than or equal to about 200%;
• and
• an intermediate layer comprising a soft metal foil interposed between the multilayer film and the core structure,
• wherein during the laminating, the outer surface of the sealing layer is pressed directly against the lacquer layer.