Mechanically and thermally responsive polymer yarn for industrial fabric application

Abstract

Yarn for an industrial fabric which is subjected to a heat-set temperature during production, the yarn being made from a polymeric material, the polymeric material including a first phase and a second phase. The melting temperature of the second phase is equal to or less than the heat-set temperature and the melting temperature of the first phase is higher than the heat-set temperature.

1 . A yarn for an industrial fabric, comprising: 
 a polymeric material having a first phase and a second phase, said first phase having a first melting temperature, said second phase having a second melting temperature in the range of between approximately 90° C. to 260° C., said second melting temperature being lower than said first melting temperature.    
   
   
       2 . The yarn of  claim 1 , wherein the industrial fabric has a maximum operation temperature, said second melting temperature being higher than said maximum operation temperature.  
   
   
       3 . The yarn of  claim 1 , wherein said second phase is an amorphous phase, said second melting temperature being a softening temperature.  
   
   
       4 . The yarn of  claim 1 , wherein said second melting temperature is in the range of between approximately 120° C. to 220° C.  
   
   
       5 . The yarn of  claim 4 , wherein said second melting temperature is in the range of between approximately 160° C. to 220° C.  
   
   
       6 . The yarn of  claim 1 , wherein said second melting temperature is at least 30° C. lower than said first melting temperature.  
   
   
       7 . The yarn of  claim 1 , wherein said polymeric material is a polymer blend, said first phase including a first polymer component, said second phase including a second polymer component, said first polymer component and said second polymer component being immiscible.  
   
   
       8 . The yarn of  claim 7 , wherein said first component includes at least one of homepolymers of polyesters, copolymers of polyesters, homepolymers of polyamides, copolymers of polyamides and PPS.  
   
   
       9 . The yarn of  claim 7 , wherein said second component includes at least one of polyolefins, polyamides and fluoropolymers.  
   
   
       10 . The yarn of  claim 9 , wherein said first component and said second component are blended together forming a blend, said blend including between approximately 51% and 99% by weight of said first component and between approximately 49% and 1% by weight of said second component.  
   
   
       11 . The yarn of  claim 10 , wherein said blend includes between approximately 51% and 99% by weight of said first component and between approximately 49% and 1% by weight of said second component.  
   
   
       12 . The yarn of  claim 10 , further comprising at least one compatibilizer.  
   
   
       13 . The yarn of  claim 12 , wherein said compatibilizer is a part of said blend in an amount of between approximately 0.01% to 10% by weight.  
   
   
       14 . The yarn of  claim 13 , wherein said compatibilizer is a part of said blend in an amount of between approximately 0.1% to 5% by weight.  
   
   
       15 . The yarn of  claim 12 , wherein said compatibilizer is a physical compatibilizer.  
   
   
       16 . The yarn of  claim 15 , wherein said physical compatibilizer includes at least one of Ethylene Methyl Acrylate Copolymer and Ethylene Butyl Acrylate Copolymer.  
   
   
       17 . The yarn of  claim 12 , wherein at least one said compatibilizer is a reactive compatibilizer.  
   
   
       18 . The yarn of  claim 17 , wherein said reactive compatibilizer includes at least one of Ethylene-g-Maleic Anhydride Copolymers and Ethylene-g-Glycidal Methacrylate.  
   
   
       19 . The yarn of  claim 10 , further comprising at least one stabilizer.  
   
   
       20 . The yarn of  claim 19 , wherein said stabilizer is a part of said blend in an amount of between approximately 0.1% to 10% by weight.  
   
   
       21 . The yarn of  claim 20 , wherein said stabilizer is a part of said blend in an amount of between approximately 0.5% to 5% by weight.  
   
   
       22 . The yarn of  claim 19 , wherein said at least one stabilizer is a hydrolysis stabilizer.  
   
   
       23 . The yarn of  claim 22 , wherein said hydrolysis stabilizer is a carbodiimide compound.  
   
   
       24 . The yarn of  claim 19 , wherein said at least one stabilizer is an anti-oxidation stabilizer.  
   
   
       25 . The yarn of  claim 1 , wherein said polymeric material has at least one of an elongation at yield point of greater than approximately 5% and an other yield point of greater than approximately 20%.  
   
   
       26 . The yarn of  claim 1 , wherein the yarn is a monofilament.  
   
   
       27 . The yarn of  claim 1 , wherein the yarn is a multifilament.  
   
   
       28 . The yarn of  claim 1 , wherein the yarn has a diameter in the range of approximately 0.20 mm to approximately 2.0 mm.  
   
   
       29 . The yarn of  claim 28 , wherein said diameter is in the range of between approximately 0.4 mm to 1.0 mm.  
   
   
       30 . The yarn of  claim 1 , wherein the yarn is one of round and profiled.  
   
   
       31 . The yarn of  claim 30 , wherein the yarn is profiled having chamfered edges.  
   
   
       32 . A process of making a yarn for an industrial fabric, comprising the step of: 
 forming a polymeric material having a first phase and a second phase, said first phase having a first melting temperature, said second phase having a second melting temperature in the range of between approximately 90° C. to 260° C., said second melting temperature being lower than said first melting temperature.    
   
   
       33 . An industrial fabric, comprising: 
 a set of weft yarns;    a set of warp yarns being interwoven with said set of weft yarns, thereby defining interwoven yarns, said interwoven yarns being subjected to a heat-set treatment, said set of weft yarns and said set of warp yarns each have a crimp level after said heat-set treatment, wherein during said heat-set treatment a tension of from approximately 1 kN/m to approximately 6 kN/m is applied to said warp yarns, while a temperature of from between approximately 90° C. to 260° C. is applied to said interwoven yarns, at least one said warp yarn of said set of warp yarns and at least one weft yarn of said set of weft yarns have a crimp level ratio of less than approximately 4, wherein said crimp level for each yarn is the difference of a length along a crimped line of said yarn and a length along a straight line of said yarn divided by said length along said straight line of said yarn.    
   
   
       34 . The fabric of  claim 33 , wherein said tension is between approximately 1.5 kN/m to 5 kN/m.  
   
   
       35 . The fabric of  claim 34 , wherein said temperature is between approximately 160° C. to 220° C.  
   
   
       36 . The fabric of  claim 33 , wherein said crimp level ratio is less than approximately 3.5.  
   
   
       37 . The fabric of  claim 36 , wherein said crimp level ratio is less than approximately 3.0.  
   
   
       38 . The fabric of  claim 37 , wherein said crimp level ratio is less than approximately 2.  
   
   
       39 . An industrial fabric, comprising: 
 a plurality of yarns made of a polymer blend, said polymer blend including: 
 a first polymer component having a melting temperature; and  
 a second polymer component, said first polymer component and said second 5 polymer component being immiscible, said second polymer component having a melting temperature in the range of between approximately 90° C. to 260° C., said melting temperature of said second polymer component being lower than said melting temperature of said first polymer component.  
   
   
   
       40 . The fabric of  claim 39 , wherein said plurality of yarns include at least one of a weft yarn and a warp yarn.  
   
   
       41 . The fabric of  claim 39 , wherein at least one of said plurality of yarns is pulled during a heat-set treatment resulting in a crimp level in the range of between approximately 4.0% to 6.5%.  
   
   
       42 . The fabric of  claim 41 , wherein said crimp level is in the range of between approximately 4.5% to 6.0%.  
   
   
       43 . The fabric of  claim 39 , wherein the fabric is formed into a papermaking fabric including one of a forming fabric, a dryer fabric and a base of a press fabric.  
   
   
       44 . The fabric of  claim 43 , wherein the fabric is a dryer fabric having a permeability in the range of between approximately 50 cfm to 200 cfm.  
   
   
       45 . The fabric of  claim 44 , wherein said permeability is in the range of between approximately 75 cfm to 150 cfm.