In-mold labeled container and molding process thereof

A process for blow-molding an in-mold labeled container comprising a main container having in-mold labels fixed to an outer peripheral surface of a body in a manner extending around the body over a whole circumferential length, the body having a thinnest wall portion formed annularly in a middle part of the body as viewed in a height direction, the process comprising:

• a first process that comprises extrusion molding a parison so as to give the parison an annular thin-wall portion by means of wall thickness control, the parison being later blow-molded into the main container,
• a second process that comprises pinching the parison with both halves of a split mold, while setting the thin-wall portion at a position opposed to body molding planes of the split mold when the pair of halves of the split mold is clamped with each in-mold label being held by a corresponding body molding plane, and
• a third process that comprises blow molding the parison into the main container to expand and deform the thin-wall portion into the thinnest wall portion of the container, wherein the thin-wall portion first contacts with the in-mold labels during a period when the perison is being blow-molded in order to create the body that has an inner peripheral body surface with a wall thickness thereof gradually growing thick toward upper and lower ends of the body starting from the thinnest wall portion and the outer peripheral surface that extends along one plane such that the outer peripheral surface is flat.