Film winding method and apparatus, and lay-on roll for the film winding apparatus

Abstract

In a film winding method, continuous polymer film of cellulose acetate being supplied is wound into a form of a film roll. During the winding step, looseness of outer turns of the film roll is prevented by pressing a rotatable lay-on roll against the film roll. The lay-on roll includes a surface material, formed in a cylindrical shape, for contacting the film roll. The surface material includes rubber, has volume resistivity of 10 2 -10 12 Ωcm, and hardness of 30-70.

What is claimed is:  
     
         1 . A film winding method comprising steps of: 
 winding continuous polymer film into a form of a film roll; and    during said winding, preventing looseness of outer turns of said film roll by pressing a rotatable lay-on roll against a peripheral surface of said film roll;    wherein said lay-on roll includes a surface material, formed in a cylindrical shape, and including rubber which has volume resistivity of 10 2 -10 12  Ωcm, and hardness of 30-70.    
     
     
         2 . A film winding method as defined in  claim 1 , wherein said lay-on roll further includes a roll body about which said surface material is disposed in a cylindrical form.  
     
     
         3 . A film winding method as defined in  claim 2 , wherein said roll body is formed from metal.  
     
     
         4 . A film winding method as defined in  claim 1 , wherein said surface material has said volume resistivity of 10 4 -10 8  Ωcm.  
     
     
         5 . A film winding method as defined in  claim 4 , wherein said surface material has said hardness of 30-60.  
     
     
         6 . A film winding method as defined in  claim 1 , wherein said surface material has high resistance to ozone.  
     
     
         7 . A film winding method as defined in  claim 1 , wherein a winding speed of said polymer film is 30 meters per minute or more.  
     
     
         8 . A film winding method as defined in  claim 1 , wherein said polymer film has a thickness of 125 microns or less.  
     
     
         9 . A film winding method as defined in  claim 8 , wherein said polymer film has said thickness of 85 microns or less.  
     
     
         10 . A film winding method as defined in  claim 1 , wherein a pressing force of said lay-on roll to said film roll is 10-100 N.  
     
     
         11 . A film winding method as defined in  claim 10 , wherein said pressing force is 20-80 N.  
     
     
         12 . A film winding method as defined in  claim 11 , wherein said pressing force is decreased in a range from 60 N down to 30 N according to an increase in a radius of said film roll.  
     
     
         13 . A film winding method as defined in  claim 1 , wherein said polymer film is cellulose acylate or polyester.  
     
     
         14 . A film winding method as defined in  claim 1 , wherein said surface material further includes carbon.  
     
     
         15 . A film winding method as defined in  claim 1 , wherein said polymer film has a width of 600-3,500 mm.  
     
     
         16 . A film winding method as defined in  claim 1 , wherein a length of winding of said polymer film into said film roll is 500-10,000 meters.  
     
     
         17 . A lay-on roll for a film winding apparatus for winding continuous polymer film into a form of a film roll, said lay-on roll being pressed against said film roll while said polymer film is wound by said film winding apparatus, for preventing looseness of outer turns of said film roll, said lay-on roll comprising: 
 a rotatable roll body; and    a surface material, disposed about said roll body, and including rubber which has volume resistivity of 10 2 -10 12  Ωcm, and hardness of 30-70.    
     
     
         18 . A lay-on roll as defined in  claim 17 , wherein said surface material has high resistance to ozone.  
     
     
         19 . A lay-on roll as defined in  claim 17 , wherein a pressing force of being pressed to said film roll is 10-100 N.  
     
     
         20 . A lay-on roll as defined in  claim 17 , wherein said polymer film is cellulose acylate or polyester.  
     
     
         21 . A film winding apparatus comprising: 
 a spindle for winding continuous polymer film into a form of a film roll thereabout; and    a lay-on roll, pressed against a peripheral surface of said film roll while said polymer film is wound about said spindle, for preventing looseness of outer turns of said film roll;    said lay-on roll including: 
 a rotatable roll body; and  
 a surface material, disposed about said roll body, and including rubber which has volume resistivity of 10 2 -10 12  Ωcm, and hardness of 30-70.