Method of manufacturing elastic cylindrical body, method of manufacturing elastic roll, elastic cylindrical body and elastic roll

Abstract

A liquid mixture containing a liquid polymeric material and a granular filler is injected into a mold ( 11 ) for centrifugal molding and subjected to centrifugal molding, thereby preparing a cylindrical body including a homogeneous dispersion layer ( 2 ) having the filler homogeneously dispersed in the polymeric material and a high-density packed bed ( 1 ), formed on the outer peripheral surface side or on the inner peripheral surface side of the homogeneous dispersion layer ( 2 ), containing the aforementioned polymeric material more densely filled with the aforementioned filler. The high-density packed bed ( 1 ) is removed for exposing the surface of the homogeneous dispersion layer ( 2 ). According to this structure, the yield of the elastic cylindrical body can be improved.

1 . An elastic cylindrical body containing a polymeric material and a filler, 
 obtained by centrifugal molding, wherein    the difference between the hardness of the outer surface and the hardness of the inner surface is within 2 degrees (JIS D),    the difference in hardness per millimeter in the thickness direction is within 1 degree (JIS D), and    the 80 cumulative weight % particle diameter of said filler [Dp] ranges from 0.01 μm to 20 μm.    
     
     
         2 . An elastic cylindrical body containing a polymeric material and a filler, 
 obtained by centrifugal molding, wherein    the difference between the ash content on an outer surface portion and the ash content on an inner surface portion is within 20%,    the difference in ash content per millimeter in the thickness direction is within 10% and    the 80 cumulative weight % particle diameter of said filler [Dp] ranges from 0.01 μm to 20 μm    
     
     
         3 . An elastic roll including a core (3) and an elastic cylindrical body located on the outer side of said core (3) and integrated with said core (3), wherein 
 said elastic cylindrical body contains a polymeric material and a filler, and    is obtained by centrifugal molding,    the difference between the hardness of the outer surface and the hardness of the inner surface is within 2 degrees (JIS D),    the difference in hardness per millimeter in the thickness direction is within 1 degree (JIS D) and    the 80 cumulative weight % particle diameter of said filler [Dp] ranges from 0.01 μm to 20 μm.    
     
     
         4 . An elastic roll including a core (3) and an elastic cylindrical body located on the outer side of said core (3) and integrated with said core (3), wherein 
 said elastic cylindrical body contains a polymeric material and a filler, and    is obtained by centrifugal molding,    the difference between the ash content on an outer surface portion and the ash content on an inner surface portion is within 20%,    the difference in ash content per millimeter in the thickness direction is within 10% and    the 80 cumulative weight % particle diameter of said filler [Dp] ranges from 0.01 μm to 20 μm.    
     
     
         5 . The elastic roll according to  claim 3 , wherein said elastic roll is a paper calender roll.