Papermaking press felt and papermaking press apparatus

Abstract

A papermaking press felt includes a plurality of base materials of an identical or a different type; and a fiber web layered on one or both faces of at least one of the base materials and integrally entwined therewith by needling. At least one of the base materials is a woven fabric including a machine direction (MD) yarn and a cross-machine direction (CD) yarn, such that one thereof is a twine made from a filament having a fineness of 50 to 250 dtex, and the other thereof is a single yarn having a fineness of 50 to 600 dtex.

1 . A papermaking press felt, comprising: 
 a plurality of base materials of an identical or a different type; and    a fiber web layered on one or both faces of at least one of the base materials and integrally entwined therewith by needling;    wherein at least one of the base materials is a woven fabric including a machine direction (MD) yarn and a cross-machine direction (CD) yarn, such that one thereof is a twine made from a filament having a fineness of 50 to 250 dtex, and the other thereof is a single yarn having a fineness of 50 to 600 dtex.    
   
   
       2 . The papermaking press felt as claimed in  claim 1 , wherein the woven fabric is woven with an end portion thereof closed, and the woven fabric is wound a plurality of times to thus form a plurality of fabric layers, such that the gap between the aligned twines is filled by the flattening effect of the twine.  
   
   
       3 . The papermaking press felt as claimed in  claim 2 , 
 wherein the woven fabric is a plain woven fabric.    
   
   
       4 . The papermaking press felt as claimed in  claim 1 , of the first press apparatus; 
 wherein at least one of a pick-up felt and a bottom felt of the first press apparatus and a top felt and a bottom felt of the second press apparatus includes the one of papermaking press felts.    wherein the woven fabric is a multiwoven fabric including a double-woven or a thicker structure, and    the gap between the aligned twines forming the multiwoven fabric is filled by the flattening effect of the twine.    
   
   
       5 . The papermaking press felt as claimed in  claim 1 , 
 wherein the twine is a loosely twisted twine given a final twist of 30 to 100 times per meter, with a ratio of a preliminary twist against the final twist in a range of 1.2 to 1.4.    
   
   
       6 . The papermaking press felt as claimed in  claim 1 , 
 wherein either of the machine direction (MD) yarn or a cross-machine direction (CD) yarn constituting the woven fabric is a soluble filament.    
   
   
       7 . A papermaking press apparatus, comprising: 
 a pressing section including a papermaking press felt;    wherein the paper making press felt includes: 
 a plurality of base materials of an identical or a different type, and  
 a fiber web layered on one or both faces of at least one of the base materials and integrally entwined therewith by needling; and  
   at least one of the base materials is a woven fabric including a machine direction (MD) yarn and a cross-machine direction (CD) yarn, such that one thereof is a twine made from a filament having a fineness of 50 to 250 dtex, and the other thereof is a single yarn having a fineness of 50 to 600 dtex.    
   
   
       8 . A papermaking press apparatus; comprising: 
 two pieces of papermaking press felts that hold a wet paper web therebetween to dewater from the wet paper web;    wherein at least one of the papermaking press felts includes: 
 a plurality of base materials of an identical or a different type, and  
 a fiber web layered on one or both faces of at least one of the base materials and integrally entwined therewith by needling; and  
   at least one of the base materials is a woven fabric including a machine direction (MD) yarn and a cross-machine direction (CD) yarn, such that one thereof is a twine made from a filament having a fineness of 50 to 250 dtex, and the other thereof is a single yarn having a fineness of 50 to 600 dtex.    
   
   
       9 . The papermaking press apparatus as claimed in  claim 8 , further comprising: 
 a first press apparatus which holds a wet paper web with two pieces of felts for dewatering therefrom; and    a second press apparatus installed on a downstream side of the first press apparatus;    wherein at least one of a pick-up felt and a bottom felt of the first press apparatus and a top felt and a bottom felt of the second press apparatus includes the one of papermaking press felts.    
   
   
       10 . The papermaking press apparatus as claimed in  claim 8 , further comprising: 
 a first press apparatus which holds a wet paper web with two pieces of felts for dewatering therefrom; and    a second press apparatus installed on a downstream side of the first press apparatus;    wherein each of a pick-up felt and a bottom felt of the first press apparatus and a top felt and a bottom felt of the second press apparatus includes the one of papermaking press felts.    
   
   
       11 . The papermaking press apparatus as claimed in  claim 8 , further comprising: a first press apparatus which holds a wet paper web with two pieces of felts for dewatering therefrom; 
 wherein the one of papermaking press felts is installed in the first press apparatus.