초록 ▼

In a multi-layer sheet material from which containers adapted to heat food in microwave ovens may be erected, the sheet material comprising a core layer and a transparent surface layer on each side of the core layer, the improvement comprising an intermediate layer located between the core and at le

In a multi-layer sheet material from which containers adapted to heat food in microwave ovens may be erected, the sheet material comprising a core layer and a transparent surface layer on each side of the core layer, the improvement comprising an intermediate layer located between the core and at least one of the adjacent surface layers, the intermediate layer being a relatively thin layer of polyethylene terephthalate and a design printed on one side of the intermediate layer whereby the design is visible through the adjacent surface layer and is prevented by the adjacent surface layer from being physically contacted.

대표청구항 ▼

In a multi-layer sheet material from which containers adapted to heat food in microwave ovens may be erected, said sheet material comprising a core layer and separate transparent surface layers on both sides of said core layer, the improvement comprising: (a) a single ply intermediate layer located

In a multi-layer sheet material from which containers adapted to heat food in microwave ovens may be erected, said sheet material comprising a core layer and separate transparent surface layers on both sides of said core layer, the improvement comprising: (a) a single ply intermediate layer located between said core layer and at least one of said adjacent surface layers, said intermediate layer being a relatively thin layer of polyethylene terephthalate, and (b) a design printed on each side of said intermediate layer whereby said design is visible through the adjacent surface layer and is prevented by said adjacent surface layer from being physically contacted.