Conveyor belt rubber composition, method for producing conveyor belt rubber composition, conveyor belt, and belt conveyor

{
  "publication_number": "US11498993B2",
  "country": "US",
  "kind": "B2",
  "title": "Conveyor belt rubber composition, method for producing conveyor belt rubber composition, conveyor belt, and belt conveyor",
  "abstract": "An object of the present invention is to provide a conveyor belt rubber composition having excellent cut resistance and wear resistance, a method for producing the conveyor belt rubber composition, a conveyor belt formed using the conveyor belt rubber composition, and a belt conveyor equipped with the conveyor belt. The present invention relates to a conveyor belt rubber composition containing a diene rubber containing 50 mass % or more of an aromatic vinyl-conjugated diene copolymer, wherein the aromatic vinyl-conjugated diene copolymer has a content of repeating units derived from an aromatic vinyl of more than 20 mass %, and a proportion of a vinyl structure in repeating units derived from a conjugated diene of 8 mol % or less.",
  "claims": [
    "1. A conveyor belt rubber composition comprising a diene rubber containing 50 mass % or more of an aromatic vinyl-conjugated diene copolymer, wherein the aromatic vinyl-conjugated diene copolymer has a content of repeating units derived from an aromatic vinyl of more than 20 mass %, a proportion of a vinyl structure in the repeating units derived from a conjugated diene of 8 mol % or less, a proportion of a 1,4-cis structure in the repeating units derived from the conjugated diene of from 10 to 62 mol %, and a proportion of a 1,4-trans structure in the repeating units derived from the conjugated diene of 40 mol % or less",
    "2. The conveyor belt rubber composition according to claim 1, wherein the aromatic vinyl-conjugated diene copolymer has a glass transition temperature of −50° C. or lower.",
    "3. The conveyor belt rubber composition according to claim 2, wherein the aromatic vinyl-conjugated diene copolymer has a proportion of a 1,4-cis structure in the repeating units derived from the conjugated diene of 17 to 62 mol %.",
    "4. The conveyor belt rubber composition according to claim 3, wherein the proportion of the vinyl structure is 5 mol % or less.",
    "5. The conveyor belt rubber composition according to claim 3, wherein the proportion of the 1,4-cis structure is 60 to 62 mol %.",
    "6. The conveyor belt rubber composition according to claim 5, wherein the proportion of the vinyl structure is 5 mol % or less.",
    "7. The conveyor belt rubber composition according to claim 2, wherein the proportion of the vinyl structure is 5 mol % or less.",
    "8. The conveyor belt rubber composition according to claim 2, wherein the aromatic vinyl-conjugated diene copolymer is terminally modified with at least one modifier selected from the group consisting of a titanium halide, a tin halide, a cyclic silazane, an alkoxysilane, an epoxide, an amine, a ketone, and a compound represented by the formula (N), where, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group.",
    "9. The conveyor belt rubber composition according to claim 1, wherein the aromatic vinyl-conjugated diene copolymer has a proportion of a 1,4-cis structure in the repeating units derived from the conjugated diene of 17 to 62 mol %.",
    "10. The conveyor belt rubber composition according to claim 9, wherein the proportion of the vinyl structure is 5 mol % or less.",
    "11. The conveyor belt rubber composition according to claim 9, wherein the aromatic vinyl-conjugated diene copolymer is terminally modified with at least one modifier selected from the group consisting of a titanium halide, a tin halide, a cyclic silazane, an alkoxysilane, an epoxide, an amine, a ketone, and a compound represented by the formula (N), where, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group.",
    "12. The conveyor belt rubber composition according to claim 9, wherein the proportion of the 1,4-cis structure is 60 to 62 mol %.",
    "13. The conveyor belt rubber composition according to claim 12, wherein the proportion of the vinyl structure is 5 mol % or less.",
    "14. The conveyor belt rubber composition according to claim 12, wherein the aromatic vinyl-conjugated diene copolymer is terminally modified with at least one modifier selected from the group consisting of a titanium halide, a tin halide, a cyclic silazane, an alkoxysilane, an epoxide, an amine, a ketone, and a compound represented by the formula (N), where, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group.",
    "15. The conveyor belt rubber composition according to claim 1, wherein the proportion of the vinyl structure is 5 mol % or less.",
    "16. The conveyor belt rubber composition according to claim 1, wherein the aromatic vinyl-conjugated diene copolymer is terminally modified with at least one modifier selected from the group consisting of a titanium halide, a tin halide, a cyclic silazane, an alkoxysilane, an epoxide, an amine, a ketone, and a compound represented by the formula (N), where, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group.",
    "17. A conveyor belt comprising an upper surface cover rubber layer; a reinforcing layer; and a lower surface cover rubber layer, wherein at least the upper surface cover rubber layer is formed using the conveyor belt rubber composition described in claim 1.",
    "18. A belt conveyor equipped with the conveyor belt described in claim 17.",
    "19. A method for producing a conveyor belt rubber composition, the conveyor belt rubber composition containing a diene rubber containing 50 mass % or more of an aromatic vinyl-conjugated diene copolymer, the aromatic vinyl-conjugated diene copolymer having a content of repeating units derived from an aromatic vinyl of more than 20 mass %, a proportion of a vinyl structure in repeating units derived from a conjugated diene of 8 mol % or less, a proportion of a 1,4-cis structure in the repeating units derived from the conjugated diene of from 10 to 62 mol %, and a proportion of a 1,4-trans structure in the repeating units derived from the conjugated diene of 40 mol % or less, the method comprising: copolymerizing monomers comprising the aromatic vinyl and the diene using an initiator prepared using an organolithium compound, an alkyl aluminum, and a metal alcoholate to produce the aromatic vinyl-conjugated diene copolymer.",
    "20. A method for producing a conveyor belt rubber composition, the conveyor belt rubber composition containing a diene rubber containing 50 mass % or more of an aromatic vinyl-conjugated diene copolymer, the aromatic vinyl-conjugated diene copolymer having a content of repeating units derived from an aromatic vinyl of more than 20 mass % and a proportion of vinyl structure in repeating units derived from a conjugated diene of 8 mol % or less, a proportion of a 1,4-cis structure in the repeating units derived from the conjugated diene of from 10 to 62 mol %, and a proportion of a 1,4-trans structure in the repeating units derived from the conjugated diene of 40 mol % or less, and being terminally modified with at least one modifier selected from the group consisting of a titanium halide, a tin halide, a cyclic silazane, an alkoxysilane, an epoxide, an amine, a ketone, and a compound represented by formula (N), the method comprising: copolymerizing monomers comprising the aromatic vinyl and the diene using an initiator prepared using an organolithium compound, an alkylaluminum and a metal alcoholate, and then terminating the polymerization using an electrophile selected from a titanium halide, a tin halide, a cyclic silazane, an alkoxysilane, an epoxide, an amine, a ketone, and a compound represented by formula (N) to produce the aromatic vinyl-conjugated diene copolymer, where, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group."
  ],
  "description_excerpt": "The present invention relates to a conveyor belt rubber composition, a method for producing a conveyor belt rubber composition, a conveyor belt, and a belt conveyor.\n\nVarious characteristics such as cut resistance (difficulty to be ruptured when colliding with a sharp object) and wear resistance are required for belts (conveyor belts) of belt conveyors used to transport materials and the like.\n\nAs the rubber composition used for such a conveyor belt, for example, Patent Document 1 discloses a conveyor belt rubber composition containing natural rubber (NR) and styrene-butadiene rubber (SBR).\n\nPatent Document 1: JP 2014-205789 A\n\nIn recent years, with an increase in conveying capacity, the conveyor belt is required to have improved cut resistance and wear resistance.\n\nUnder the circumstance described above, the present inventors have investigated the conveyor belt rubber composition containing natural rubber and SBR using Examples in Patent Document 1 as a reference. It has been clearly found that even though the cut resistance and the wear resistance are at relatively high levels, further improvements thereof are desired in consideration of increase of a future request level.\n\nIn light of the circumstances described above, an object of the present invention is to provide a conveyor belt rubber composition having excellent cut resistance and wear resistance, a method for producing the conveyor belt rubber composition, a conveyor belt formed using the conveyor belt rubber composition, and a belt conveyor equipped with the conveyor belt.",
  "cpc": [
    "C08F 236/10",
    "B65G 15/32",
    "B65G 15/34",
    "C08C 19/22",
    "C08K 5/057",
    "C08K 5/56",
    "C08L 15/00",
    "C08L 9/06"
  ],
  "ipc": [
    "B65G 15/32",
    "C08C 19/22",
    "C08F 236/10",
    "C08K 5/057",
    "C08K 5/56"
  ],
  "assignees": [
    "Yokohama Rubber Co Ltd"
  ],
  "inventors": [
    "Yu Shinke",
    "Deqing Zou",
    "Jun Miyaji",
    "Kazuya Uenishi"
  ],
  "filing_date": "2018-02-22",
  "publication_date": "2022-11-15",
  "grant_date": "2022-11-15",
  "priority_date": "2017-02-22",
  "application_number": "US-201816487291-A",
  "family_id": "63254433",
  "cited_by_count": 0,
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    "JP2014205789A",
    "US20160096684A1",
    "WO2017043553A1",
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    "US20190023880A1",
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    "US20190375872A1"
  ]
}