# US 2018/0022157 A1 · Radial tire having an improved belt structure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0022157 A1 - Document ID: US20180022157A1 - Status: Published application - Kind: A1 - Application number: 15/547,969 - Filed: 2016-01-22 - Published: 2018-01-25 - Earliest claimed: 2015-02-03 - Assignees: Compagnie Generale Des Etablissements Michelin - Applicants: Compagnie Generale Des Etablissements Michelin - Inventors: AURORE LARDJANE; CAMILLE ASTAIX - Web page: https://patentgrep.com/patent/US20180022157A1 ## CPC - B60C 9/2003: {characterised by the materials of the belt cords} - B60C 9/0042: {Reinforcements made of synthetic materials} - B60C 9/005: {Reinforcements made of different materials, e.g. hybrid or composite cords} - B60C 9/0064: {Reinforcements comprising monofilaments} - B60C 9/1821: {comprising discrete fibres or filaments} - B60C 9/2009: {comprising plies of different materials} - B60C 2009/2016: {comprising cords at an angle of 10 to 30 degrees to the circumferential direction} - B60C 2009/2077: {Diameters of the cords; Linear density thereof} - B60C 2009/2083: {Density in width direction} - D02G 3/48: Tyre cords {(tyre reinforcements B60C9/00; metal cords for reinforcing rubber or plastic articles D07B1/0606)} - B60C: VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES - D02G: CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS ## Abstract A radial tire, notably for a passenger vehicle or van, has an improved belt structure comprising a multilayer composite laminate with a first layer of rubber comprising heat-shrinkable circumferential textile reinforcers, preferably in the form of monofilaments or assemblies of monofilaments; this first layer radially (in the direction Z) surmounts two other layers of rubber, reinforced by reinforcers all or some of which are composite reinforcers made up of steel monofilaments sheathed with a thermoplastic material, the glass transition temperature of which is greater than 20° C. This laminate makes it possible to lighten the belts of tyres by reducing the thickness of the layers of rubber that make up part of their structure, and therefore to reduce the weight and rolling resistance of the tyres, without the risk of direct contact between the reinforcers. ## Claims ### Claim at position 1 -28. (canceled) ### Claim 29 A radial tire, defined in three main directions, circumferential, axial and radial, comprising a crown surmounted by a tread, two sidewalls, two beads, each sidewall connecting each bead to the crown, a carcass reinforcement that is anchored in each of the beads and extends in the sidewalls as far as the crown, a belt that extends in the crown in the circumferential direction and is situated radially between the carcass reinforcement and the tread, said belt comprising a multilayer composite laminate comprising at least three superposed layers of reinforcers, said reinforcers being unidirectional within each layer and embedded in a thickness of rubber, respectively, wherein, on a tread side, a first layer of rubber comprises a first row of reinforcers, said reinforcers being first reinforcers, which are oriented at an angle α of −5 to +5 degrees with respect to the circumferential direction and made of a heat-shrinkable textile material; wherein, in contact with the first layer of rubber and disposed beneath the first layer of rubber, a second layer of rubber comprises a second row of reinforcers, said reinforcers being second reinforcers, which are oriented at a given angle β, which is positive or negative, of between 10 and 30 degrees with respect to the circumferential direction and have a diameter D2 of between 0.20 mm and 0.50 mm; wherein, in contact with the second layer of rubber and disposed beneath the second layer of rubber, a third layer of rubber comprises a third row of reinforcers, said reinforcers being third reinforcers, which are oriented at an angle γ, the opposite of the angle β, itself being between 10 and 30 degrees with respect to the circumferential direction and have a diameter D3 of between 0.20 mm and 0.50 mm; and wherein all or part of the second reinforcers, the third reinforcers or both the second and third reinforcers are composite reinforcers comprising steel monofilaments which are covered with a sheath of a thermoplastic material, the glass transition temperature Tg of which is higher than 20° C. ### Claim 30 (depends on 29) The tire according to claim 29, wherein D2, D3 or both D2 and D3 are greater than 0.25 mm and less than 0.40 mm. ### Claim 31 (depends on 30) The tire according to claim 30, wherein D2, D3 or both D2 and D3 range from 0.28 to 0.35 mm. ### Claim 32 (depends on 29) The tire according to claim 29, wherein a minimum thickness Em of the thermoplastic sheath covering the steel monofilaments is between 5 and 150 μm. ### Claim 33 (depends on 32) The tire according to claim 32, wherein the minimum thickness Em is between 10 and 100 μm. ### Claim 34 (depends on 29) The tire according to claim 29, wherein the Tg is greater than 50° C. ### Claim 35 (depends on 34) The tire according to claim 34, wherein the Tg is greater than 70° C. ### Claim 36 (depends on 29) The tire according to claim 29, wherein the thermoplastic material is a polymer or a polymer composition. ### Claim 37 (depends on 36) The tire according to claim 36, wherein the polymer is a polyamide or a polyester. ### Claim 38 (depends on 29) The tire according to claim 29, wherein an envelope diameter D1 of the first reinforcers is between 0.20 mm and 1.20 mm. ### Claim 39 (depends on 38) The tire according to claim 38, wherein D1 is between 0.30 and 1.00 mm. ### Claim 40 (depends on 39) The tire according to claim 39, wherein D1 is between 0.40 and 0.80 mm. ### Claim 41 (depends on 29) The tire according to claim 29, wherein a density d1 of the first reinforcers in the first layer of rubber, measured in the axial direction, is between 70 and 130 threads/dm. ### Claim 42 (depends on 41) The tire according to claim 41, wherein the density d1 is between 80 and 120 threads/dm. ### Claim 43 (depends on 42) The tire according to claim 42, wherein the density d1 is between 90 and 110 threads/dm. ### Claim 44 (depends on 29) The tire according to claim 29, wherein all or some of the first reinforcers made of heat-shrinkable textile material are monofilaments with a diameter or thickness φ greater than 0.10 mm or assemblies of said monofilaments. ### Claim 45 (depends on 44) The tire according to claim 44, wherein φ is between 0.15 and 0.80 mm. ### Claim 46 (depends on 45) The tire according to claim 45, wherein φ is between 0.20 and 0.60 mm. ### Claim 47 (depends on 44) The tire according to claim 44, wherein the first reinforcers made of heat-shrinkable textile material are assemblies of 2 to 10 monofilaments. ### Claim 48 (depends on 47) The tire according to claim 47, wherein the first reinforcers made of heat-shrinkable textile material are assemblies of 3 to 7 monofilaments. ### Claim 49 (depends on 29) The tire according to claim 29, wherein the heat-shrinkable textile material is a polyamide or a polyester. ### Claim 50 (depends on 29) The tire according to claim 29, wherein a thermal contraction CT of the first reinforcers, after 2 minutes at 185° C., is less than 7.5%. ### Claim 51 (depends on 50) The tire according to claim 50, wherein the CT is less than 7.0%. ### Claim 52 (depends on 51) The tire according to claim 51, wherein the CT is less than 6.0%. ### Claim 53 (depends on 44) The tire according to claim 44, wherein the monofilaments or assemblies of monofilaments represent the majority of the first reinforcers of the first layer of rubber. ### Claim 54 (depends on 53) The tire according to claim 53, wherein the monofilaments or assemblies of monofilaments represent all of the first reinforcers of the first layer of rubber. ### Claim 55 (depends on 29) The tire according to claim 29, wherein densities d2 and d3, respectively, of the second reinforcers and the third reinforcers, measured in the axial direction, are between 100 and 180 threads/dm. ### Claim 56 (depends on 55) The tire according to claim 55, wherein d2 and d3 are between 110 and 170 threads/dm. ### Claim 57 (depends on 56) The tire according to claim 56, wherein d2 and d3 are between 120 and 160 threads/dm. ### Claim 58 (depends on 29) The tire according to claim 29, wherein the steel is a carbon steel. ### Claim 59 (depends on 29) The tire according to claim 29, wherein the steel monofilaments sheathed with the thermoplastic sheath represent the majority of the second reinforcers. ### Claim 60 (depends on 59) The tire according to claim 59, wherein the steel monofilaments sheathed with the thermoplastic sheath represent all of the second reinforcers. ### Claim 61 (depends on 29) The tire according to claim 29, wherein the steel monofilaments sheathed with the thermoplastic sheath represent the majority of the third reinforcers. ### Claim 62 (depends on 61) The tire according to claim 61, wherein the steel monofilaments sheathed with the thermoplastic sheath represent all of the third reinforcers. ### Claim 63 (depends on 29) The tire according to claim 29, wherein a mean thickness Ez1 of rubber separating a first reinforcer from a second reinforcer closest to it, measured in the radial direction, is less than 0.40 mm, when measured in a central part of the belt in the vulcanized state, on each side of a median plane over a total axial width of 10 cm. ### Claim 64 (depends on 63) The tire according to claim 63, wherein the mean thickness Ez1 is between 0.20 and 0.40 mm. ### Claim 65 (depends on 29) The tire according to claim 29, wherein a mean thickness Ez2 of rubber separating a second reinforcer from a third reinforcer closest to it, measured in the radial direction, is less than 0.60 mm, when measured in a central part of the belt in the vulcanized state, on each side of a median plane over a total axial width of 10 cm. ### Claim 66 (depends on 65) The tire according to claim 65, wherein the mean thickness EZ2 is between 0.35 and 0.60 mm. ### Claim 67 (depends on 29) The tire according to claim 29, wherein the following inequality is satisfied: 0.15