# US 5,350,632 A · Impregnated, dimension-stable polyester cord > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,350,632 A - Document ID: US5350632A - Status: Granted - Kind: A - Application number: 08/017,632 - Filed: 1993-02-12 - Granted: 1994-09-27 - Earliest claimed: 1985-06-19 - Assignees: Rhone-Poulenc Viscosuisse SA - Inventors: Bruno Lang - Web page: https://patentgrep.com/patent/US5350632A ## CPC - B60C 9/0042: {Reinforcements made of synthetic materials} - D01F 6/62: from polyesters - D02G 3/48: Tyre cords {(tyre reinforcements B60C9/00; metal cords for reinforcing rubber or plastic articles D07B1/0606)} - D10B 2331/04: polyesters, e.g. polyethylene terephthalate [PET] - Y10S 57/902: Reinforcing or tyre cords - Y10S 156/91: Bonding tire cord and elastomer: improved adhesive system - Y10S 428/926: Thickness of individual layer specified - Y10T 428/2913: Rod, strand, filament or fiber - Y10T 428/2915: including textile, cloth or fabric - Y10T 428/2933: Coated or with bond, impregnation or core - Y10T 428/2936: Wound or wrapped core or coating [i.e., spiral or helical] - Y10T 428/2945: Natural rubber in coating - Y10T 428/2964: Artificial fiber or filament - Y10T 428/2969: Polyamide, polyimide or polyester - B60C: VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES - D01F: CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS - D02G: CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS - D10B: INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract 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. ## Claims ### Claim 1 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. ### Claim 2 (depends on 1) Dimension-stable impregnated polyester tire cord as defined in claim 1, further displaying on vulcanization a change in length of less than 1 percent and a shrinkage force of less than 0.7 cN/tex. ### Claim 3 (depends on 1) Dimension-stable impregnated polyester tire cord as defined in claim 1, further displaying 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. ### Claim 4 (depends on 1) Dimension-stable impregnated polyester tire cord as defined in claim 1, further displaying a tension of greater than 6.8 cN/tex upon 1.5 percent strain and greater than 12 cN/tex upon 5 percent strain. ### Claim 5 (depends on 1) Dimension-stable impregnated polyester tire cord as defined in claim 1, wherein the dimension stability coefficient is from about 30'000 to 46'000 cN.sup.2 /tex.sup.2. ### Claim 6 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. ### Claim 7 (depends on 6) Dimension-stable impregnated polyester cord as defined in claim 6, wherein the polyester cord is stretched in the stretching from 4 to 7% at about 240.degree. C. ### Claim 8 (depends on 6) Dimension-stable impregnated polyester cord as defined in claim 6, wherein the polyester cord is relaxed at about 210.degree. C. ### Claim 9 (depends on 6) Dimension stable impregnated polyester cord as defined in claim 6, wherein the adhesive material comprises a resorcinol-formaldehyde latex. ### Claim 10 (depends on 9) Dimension stable impregnated polyester cord as defined in claim 9, wherein in said stretching said polyester cord is stretched at a temperature of 240.degree. C. about 7 percent and in said relaxing said polyester cord is relaxed at a temperature of 210.degree. C. about 7 percent, and said polyester tire cord has a strength of 56 cN/tex. ### Claim 11 (depends on 9) Dimension stable impregnated polyester cord as defined in claim 9, wherein in said stretching said polyester cord is stretched at a temperature of 240.degree. C. about 7 percent and in said relaxing said polyester cord is relaxed at a temperature of 210.degree. C. about 7 percent, and said polyester tire cord has an initial modulus of about 450 cN/tex. ### Claim 12 (depends on 9) Dimension stable impregnated polyester cord as defined in claim 9, wherein in said stretching said polyester cord is stretched at a temperature of 20.degree. C. about 7 percent and in said relaxing said polyester cord is relaxed at a temperature of 210.degree. C. about 7 percent, and said polyester tire cord has an initial modulus of about 450 cN/tex and a tensile strength of 56 cN/tex. ### Claim 13 (depends on 1) Dimension stable impregnated polyester cord as define din claim 1, wherein said polyester tire cord has a tensile strength of 56 cN/tex. ### Claim 14 (depends on 13) Dimension stable impregnated polyester cord as defined in claim 13, wherein said polyester tire cord has an initial modulus of about 450 cN/tex.