Method for producing multilayer laminated film

Abstract

A method for producing a multilayer laminated film comprising: laminating a resin film having a moisture percentage of 10% by weight to 60% by weight with a first transparent film and a second transparent film each having a moisture percentage of 0.5% by weight to 5% by weight to be bonded to both sides of the resin film through an adhesive or pressure-sensitive adhesive layer interposed therebetween; wherein the laminating comprising steps of: passing the resin film and the first transparent film between a pair of a first metal roll and a first elastic roll in such a manner that the first transparent film is placed on the first metal roll side so that they are bonded to each other under pressure to form a laminated film; and then, using the laminated film without winding up it and passing the laminated film and the second transparent film between a pair of a second metal roll and a second elastic roll in such a manner that the second transparent film is placed on the second metal roll side so that they are bonded to each other under pressure to form a multilayer laminated film. The method can prevent bubbles from being formed between the resin film and the transparent film.

1 . A method for producing a multilayer laminated film comprising:
 laminating a resin film having a moisture percentage of 10% by weight to 60% by weight with a first transparent film and a second transparent film each having a moisture percentage of 0.5% by weight to 5% by weight to be bonded to both sides of the resin film through an adhesive or pressure-sensitive adhesive layer interposed therebetween; wherein the laminating comprising steps of:   passing the resin film and the first transparent film between a pair of a first metal roll and a first elastic roll in such a manner that the first transparent film is placed on the first metal roll side so that they are bonded to each other under pressure to form a laminated film; and then,   using the laminated film without winding up it and passing the laminated film and the second transparent film between a pair of a second metal roll and a second elastic roll in such a manner that the second transparent film is placed on the second metal roll side so that they are bonded to each other under pressure to form a multilayer laminated film.   
     
     
         2 . The method according to  claim 1 , wherein at least one of the first metal roll and the second metal roll is an iron roll or a stainless steel roll. 
     
     
         3 . The method according to  claim 1 , wherein the first elastic roll and the second elastic roll each comprise a metallic core coated with a rubber layer or a resin layer. 
     
     
         4 . The method according to  claim 3 , wherein the rubber or resin layer of each of the first elastic roll and the second elastic roll has a hardness of 70 to 100. 
     
     
         5 . The method according to  claim 1 , wherein at least one of a lamination pressure between the first metal roll and the first elastic roll and a lamination pressure between the second metal roll and the second elastic roll is from 2 MPa to 5 MPa. 
     
     
         6 . The method according to  claim 1 , wherein the moisture percentage of the resin film is more than 20% by weight to 40% by weight.