Wet paper web transfer belt

Abstract

The object of the present invention is to provide a wet paper web transfer belt with excellent crack resistance in the regions of the wet paper web transfer belt facing the roll edges. This is achieved by an endless wet paper web transfer belt travelling by rotation while being supported by a plurality of rolls in the press part of a papermaking machine; wherein the wet paper web transfer belt has at least an outer circumferential resin layer on the wet paper supporting side, the outer circumferential resin layer comprises roll edge-facing regions positioned to face both edges in the width direction of at least one of the plurality of rolls and a central region positioned between the roll edge-facing regions, the difference in the thickness between the thickness of the roll edge-facing regions and the thickness of the central region is 0.5 mm or less, and the maximum profile valley depth Rv of the outer circumferential surface of the roll edge-facing regions is 40 μm or less.

1 . An endless wet paper web transfer belt travelling by rotation while being supported by a plurality of rolls in the press part of a papermaking machine; wherein the wet paper web transfer belt has at least an outer circumferential resin layer on the wet paper supporting side, the outer circumferential resin layer comprises roll edge-facing regions positioned to face both edges in the width direction of at least one of the plurality of rolls and a central region positioned between the roll edge-facing regions, the difference in the thickness between the thickness of the roll edge-facing regions and the thickness of the central region is 0.5 mm or less, and the maximum profile valley depth Rv of the outer circumferential surface of the roll edge-facing regions is 40 μm or less. 
     
     
         2 . The wet paper web transfer belt according to  claim 1 ; wherein the thickness of the roll edge-facing regions of the wet paper web transfer belt is equal to the thickness of the central region. 
     
     
         3 . The wet paper web transfer belt according to  claim 1 ; wherein the thickness of the roll edge-facing regions of the wet paper web transfer belt is smaller than the thickness of the central region. 
     
     
         4 . The wet paper web transfer belt according to  claim 1 ; wherein a straight taper is provided from any position on the outer circumferential surface of the roll edge-facing region of the wet paper web transfer belt towards the edge of the wet paper web transfer belt in the opposite direction of the central region. 
     
     
         5 . The wet paper web transfer belt according to  claim 1 ; wherein an upward convex or downward convex curved taper is provided from any position on the outer circumferential surface of the roll edge-facing region of the wet paper web transfer belt towards the edge of the wet paper web transfer belt in the opposite direction of the central region. 
     
     
         6 . The wet paper web transfer belt according to  claim 1 ; wherein the difference in the thickness between the thickness of the roll edge-facing regions and the thickness of the central region is 0.3 mm or less. 
     
     
         7 . The wet paper web transfer belt according to  claim 1 ; wherein the maximum profile valley depth Rv is 30 μm or less. 
     
     
         8 . An endless wet paper web transfer belt travelling by rotation while being supported by a plurality of rolls in the press part of a papermaking machine; wherein the wet paper web transfer belt has at least an outer circumferential resin layer on the wet paper supporting side, the outer circumferential resin layer comprises roll edge-facing regions positioned to face both edges in the width direction of at least one of the plurality of rolls, a central region positioned between the roll edge-facing regions, and edge regions positioned at the outside of the roll edge-facing regions, the difference in the thickness between the thickness of the roll edge-facing regions and the thickness of the central region is 0.5 mm or less, and the maximum profile valley depth Rv of the outer circumferential surface of the roll edge-facing regions is 40 μm or less. 
     
     
         9 . The wet paper web transfer belt according to  claim 8 ; wherein the thickness of the roll edge-facing regions of the wet paper web transfer belt is equal to the thickness of the central region. 
     
     
         10 . The wet paper web transfer belt according to  claim 8 ; wherein the thickness of the roll edge-facing regions of the wet paper web transfer belt is smaller than the thickness of the central region. 
     
     
         11 . The wet paper web transfer belt according to  claim 8 ; wherein a straight taper is provided in any position from any position of the outer circumferential surface of the roll edge-facing region of the wet paper web transfer belt towards the edge of the wet paper web transfer belt in the opposite direction of the central region. 
     
     
         12 . The wet paper web transfer belt according to  claim 8 ; wherein an upward convex or downward convex curved taper is provided in any position from any position of the outer circumferential surface of the roll edge-facing region of the wet paper web transfer belt towards the edge of the wet paper web transfer belt in the opposite direction of the central region. 
     
     
         13 . The wet paper web transfer belt according to  claim 8 ; wherein the difference in the thickness between the thickness of the roll edge-facing regions and the thickness of the central region is 0.3 mm or less. 
     
     
         14 . The wet paper web transfer belt according to  claim 8 ; wherein the maximum profile valley depth Rv is 30 μm or less. 
     
     
         15 . The wet paper web transfer belt according to  claim 1 ; wherein the above-mentioned at least one roll is a guide roll. 
     
     
         16 . The wet paper web transfer belt according to  claim 8 ; wherein the above-mentioned at least one roll is a guide roll. 
     
     
         17 . The wet paper web transfer belt according to  claim 1 ; wherein the above-mentioned at least one roll is a press roll facing the shoe of a shoe press device. 
     
     
         18 . The wet paper web transfer belt according to  claim 8 ; wherein the above-mentioned at least one roll is a press roll facing the shoe of a shoe press device.