Hydraulic or pneumatic device comprising tube comprising polyamide resin

Abstract

A hydraulic or pneumatic device is described, which comprises a tube comprising a polyamide resin composition comprising (A) from 70 to 97% by weight, based on the weight of the polyamide resin composition, of a polyamide resin and (B) from 3 to 30% by weight, based on the weight of the polyamide resin composition, of a plasticizer comprising an ester of p- and/or o-hydroxybenzoic acid with a C 12 -C 22 aliphatic alcohol having a branched chain and a component comprising a rubber compound comprising a polar rubber as a main component, and which exhibits a high reliability over an extended period of time.

What is claimed is:  
     
         1 . A hydraulic or pneumatic device comprising: 
 a tube comprising a polyamide resin composition comprising: 
 (A) from 70 to 97% by weight, based on the weight of the polyamide resin composition, of a polyamide resin and  
 (B) from 3 to 30% by weight, based on the weight of the polyamide resin composition, of a plasticizer comprising an ester of at least one of p-hydroxybenzoic acid and o-hydroxybenzoic acid with a C 12 -C 22  aliphatic alcohol having a branched chain and  
   a component comprising a rubber compound comprising a polar rubber as a main component.    
     
     
         2 . A hydraulic or pneumatic device comprising: 
 a tube comprising a polyamide resin composition comprising: 
 (A) from 50 to 96% by weight, based on the weight of the polyamide resin composition, of a polyamide resin,  
 (B) from 3 to 30% by weight, based on the weight of the polyamide resin composition, of a plasticizer comprising an ester of at least one of p-hydroxybenzoic acid and o-hydroxybenzoic acid with a C 12 -C 22  aliphatic alcohol having a branched chain and  
 (C) from 1 to 20% by weight, based on the weight of the polyamide resin composition, of an impact-resistant material and  
   a component comprising a rubber compound comprising a polar rubber as a main component.    
     
     
         3 . The hydraulic or pneumatic device according to  claim 1 , wherein said polyamide resin is polyamide 6, polyamide 11, polyamide 12, polyamide 66, polyamide 610, polyamide 612 or copolymer thereof.  
     
     
         4 . The hydraulic or pneumatic device according to  claim 2 , wherein said polyamide resin is polyamide 6, polyamide 11, polyamide 12, polyamide 66, polyamide 610, polyamide 612 or copolymer thereof.  
     
     
         5 . The hydraulic or pneumatic device according to  claim 1 , wherein said polar rubber comprises NBR as a main component.  
     
     
         6 . The hydraulic or pneumatic device according to  claim 2 , wherein said polar rubber comprises NBR as a main component.  
     
     
         7 . The hydraulic or pneumatic device according to  claim 1 , wherein said component comprising a rubber compound comprises a clamping part used as a sealing material at least at one point.  
     
     
         8 . The hydraulic or pneumatic device according to  claim 2 , wherein said component comprising a rubber compound comprises a clamping part used as a sealing material at least at one point.