Method of making plastic container with multilayer label applied by in-mold labeling

The method of labeling a plastic container which comprises

• forming a label by heat bonding a relatively thick cellular layer to a thin inner non-cellular layer compatible with the cellular layer without adhesives and to a thin outer non-cellular layer compatible with the cellular layer without adhesives, said inner layer being made of a material compatible for heat bonding with said container without adhesives such that the layers are bonded to one another without an intervening adhesive layer therebetween,
• positioning said label on a mold cavity with the outer layer engaging the mold,
• positioning a hot parison at molding temperature adjacent the cavity,
• expanding the parison by fluid pressure against the side wall of the mold to form a container,
• providing a thickness and a density for said cellular layer so that the cellular layer comprises the major portion of the thickness of the label such that the inner layer is insulated from the outer layer of the label by the intermediate non-cellular layer so that the heat from the container heats the inner surface of the inner layer sufficiently to heat bond the label to the outer surface of the container without an adhesive layer between the container and the inner layer and without distorting the label.