Hybrid Cord and Use Thereof

Abstract

A hybrid cord comprises (i) a first yarn, without initial S or Z twist, of continuous polymeric filaments forming the core of the cord, the yarn being a non-bulked yarn, (ii) a second yarn, without initial S or Z twist, of continuous polymeric filaments, the second yarn being a bulked yarn that is wrapped around the first yarn, wherein (a) the second yarn is wrapped around the first yarn at an angle of from 5 to 40 degrees, (b) the second yarn has a length that is from 4 to 35 percent longer than that of the first yarn, and (c) the hybrid cord is unbalanced and has an S or Z twist.

What is claimed is: 
     
         1 . A hybrid cord comprising
 (i) a first yarn, without initial S or Z twist, of continuous polymeric filaments forming the core of the cord, the yarn having a tenacity of 2.2-16.6 g/dtex, a modulus of from 1 to 20 GPa and an elongation at break of greater than 8%, the yarn being a non-bulked yarn,   (ii) a second yarn, without initial S or Z twist, of continuous polymeric filaments, the yarn having a tenacity of greater than 16.6 g/dtex, a modulus of greater than 20 GPa and an elongation at break of no greater than 8%, the second yarn being a bulked yarn that is wrapped around the first yarn,   
       wherein,
 (a) the second yarn is wrapped around the first yarn at an angle of from 5 to 40 degrees, 
 (b) the second yarn has a length that is from 4 to 35 percent longer than that of the first yarn, and 
 (c) the hybrid cord is unbalanced and has an S or Z twist. 
 
     
     
         2 . The cord of  claim 1 , wherein the polymer of the first or second yarns is polyester, aliphatic polyamide, aromatic polyamide, aromatic co-polyamide, aromatic copolymer, polyazole, polyimide, polyamide-imid or a bio-based polymer. 
     
     
         3 . The cord of  claim 1 , wherein the second yarn has a length that is from 6 to 15 percent longer than that of the first yarn. 
     
     
         4 . The cord of  claim 2 , wherein the aromatic polyamide is m-aramid or p-aramid. 
     
     
         5 . The cord of  claim 2  wherein the polyazole is polyoxadiazole. 
     
     
         6 . The cord of  claim 2 , wherein the aromatic copolymer is a copolymer of para-phenylenediamine, 5(6)-amino-2-(p-aminophenyl)benzimidazole and terephthaloyl dichloride. 
     
     
         7 . The cord of  claim 3 , wherein the second yarn has a length that is from 4 to 10 percent longer than that of the first yarn. 
     
     
         8 . The cord of  claim 4  wherein the first yarn is m-aramid and the second yarn is p-aramid. 
     
     
         9 . A turbocharger hose comprising the cord of  claim 1  as a reinforcement material.