Process and apparatus for producing a laminated structure composed of a substrate web and a thermoplastic resin web extrusion-coated thereon

In a process for producing a laminated structure composed of a substrate web and a thermoplastic resin web extrusion-coated thereon which comprises melt-extruding a thermoplastic resin from the lip of a T-die composed of a die body and a die jowl to form a thermoplastic resin web in the molten state and passing the thermoplastic resin web together with a substrate in web form through a laminating roll unit consisting at least of a pair of a cooling roll and a nip roll and located apart from the die lip with an air-gap space formed between the die lip and the laminating roll unit, the improvement comprising

• (1) blowing an oxidizing gas selected from the group consisting of oxygen, ozone, air, a mixture of at least two of these, and a mixture of at least one of oxygen and ozone with an inert gas in said air-gap space to that surface of the molten thermoplastic resin web which is to make contact with the substrate web, at a flow rate of about 0.02 to about 2 Nm.sup.3 per kilogram of the thermoplastic resin extruded, whereby volatile substances evolved from said surface of the molten thermoplastic resin web are blown off said surface and removing said oxidizing gas and said volatile substances from the air-gap space, and
• (2) blowing an inert gas in said air-gap space to that surface of the molten thermoplastic resin web which is to make contact with the cooling roll, at a flow rate of about 0.02 to about 2 Nm.sup.3 per kilogram of the thermoplastic resin extruded, whereby volatile substances evolved from the surface of the molten thermoplastic resin web are blown off said surface and removing said inert gas and said volatile substances from the air-gap space.