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US 5,350,632 AGranted
Impregnated, dimension-stable polyester cord
AssigneeRhone-Poulenc Viscosuisse SA
InventorBruno Lang
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AssigneeRhone-Poulenc Viscosuisse SA
InventorBruno Lang
Estimating the term…
The dimension-stable impregnated polyester tire cord is at least 95% by weight polyethylene terephthalate and has an intrinsic viscosity of 0.70 dl/g to 0.89 dl/g for undrawn cord, a fineness of at least 1100 x 2 dtex, a dimension stability coefficient of at least 30'000 cN.sup.2 /tex.sup.2, a thermal shrinkage of about 0.8 percent measured at a temperature of 160.degree. C. with 0.1 cN/tex pre-stress and a permanent lengthening of less than 1.5 percent at a tire pressure of 2 bar and a temperature of 100.degree. C., so as to reduce shrinkage during vulcanization and in tires heated in operation and so as to provide a quieter running tire. The fatigue resistance of this polyester tire cord suffers a drop in tensile strength of less than 20 percent measured at 10.8 MC with 6 percent strain and 6 percent compression so that tires made from the polyester cord have a greater durability and increased life.
Dimension-stable impregnated polyester tire cord comprising at least 95% by weight polyethylene terephthalate and having an intrinsic viscosity of 0.70 dl/g to 0.89 dl/g for undrawn cord, a fineness of at least 1100.times.2 dtex, a dimension stability coefficient of at least 30'000 cN.sup.2 /tex.sup.2, a thermal shrinkage of about 0.8 percent measured at a temperature of 160.degree. C. with 0.1 cN/tex pre-stress and a permanent lengthening of less than 1.5 percent at a tire pressure of 2 bar and a temperature of 100.degree. C., so as to reduce shrinkage during vulcanization and in tires heated in operation and so as to provide a quieter running tire.
Dimension-stable impregnated polyester cord comprising at least 95% by weight polyethylene terephthalate and having an intrinsic viscosity of 0.70 dl/g to 0.89 dl/g for undrawn cord, a fineness of at least 1100.times.2 dtex, a dimension stability coefficient of at least 30'000 cN.sup.2 /tex.sup.2, a thermal shrinkage of about 0.8 percent measured at a temperature of 160.degree. C. with 0.1 cN/tex pre-stress, a permanent lengthening of less than 1.5 percent at a tire pressure of 2 bar and a temperature of 100.degree. C. and a fatigue resistance such that said polyester tire cord suffers a drop in tensile strength of less than 20 percent measured at 10.8 MC with 6 percent strain and 6 percent compression so that said tires made from the polyester cord have a greater durability and increased life and made by a process including the steps of stretching from 3 to 8 percent at a temperature of from 220.degree.-250.degree. C. and after the stretching and impregnating, relaxing the polyester cord from 3 to 7 percent at a temperature of from 190.degree. to 250.degree. C.
Dependencies are inferred from the claim text.