Metal-rubber composite, conveyor belt, hose, rubber track, and tire

{
  "publication_number": "US12428539B2",
  "country": "US",
  "kind": "B2",
  "title": "Metal-rubber composite, conveyor belt, hose, rubber track, and tire",
  "abstract": "A metal-rubber composite, comprising a metal and a rubber of which at least a portion is adhered to the metal, the composite is characterized in that: a ratio (C 1 /C 2) of the total concentration (C 1) of at least one metal element selected from the group consisting of bismuth, copper, antimony, silver, niobium, molybdenum, zirconium, and nickel in a region within 100 nm measured from an adhesion interface of the metal and the rubber toward the rubber side, with respect to the total concentration (C 2) of at least one metal element selected from the group consisting of bismuth, copper, antimony, silver, niobium, molybdenum, zirconium, and nickel in a region between the 100 nm depth and the 200 nm depth, measured from the adhesion interface toward the rubber side, is 7.0 or larger.",
  "claims": [
    "1. A metal-rubber composite, comprising a metal and a rubber of which at least a portion is adhered to the metal, the composite characterized in that: the metal is plated with zinc; the rubber is composed of a rubber composition containing at least one selected from the group consisting of: (1) a metal salt of carboxylic acid, having 2 to 25 carbon atoms and any of bismuth, copper, antimony, silver, niobium, molybdenum, zirconium, and nickel as the metal species thereof; and (2) a compound represented by general formula (A) shown below, [(RCOO) x MO] 3 Z (A) in the general formula (A), “Z” represents one of formulae (z-1), (z-2), (z-3) and (z-4) shown below, “M” represents bismuth, copper, antimony, silver, niobium, molybdenum, zirconium or nickel, each “(RCOO)” independently represents a residue of C 2 -C 25 aliphatic carboxylic acid, and “x” represents an integer equal to {(valence of M)−1}; a ratio (C 1 /C 2) of the total concentration (C 1) of at least one metal element selected from the group consisting of bismuth, copper, antimony, silver, niobium, molybdenum, zirconium, and nickel originally contained in the rubber in a region within 100 nm measured from an adhesion interface of the metal and the rubber toward the rubber side, with respect to the total concentration (C 2) of at least one metal element selected from the group consisting of bismuth, copper, antimony, silver, niobium, molybdenum, zirconium, and nickel originally contained in the rubber in a region between the 100 nm depth and the 200 nm depth, measured from the adhesion interface toward the rubber side, is 7.0 or larger.",
    "2. The metal-rubber composite of claim 1, wherein the rubber is composed of a rubber composition containing 0.01 to 10 parts by mass of sulfur with respect to 100 parts by mass of a rubber component.",
    "3. The metal-rubber composite of claim 2, wherein the metal is plated with only zinc.",
    "4. The metal-rubber composite of claim 1, wherein the rubber is composed of a rubber composition containing ≥2 parts by mass of silica with respect to 100 parts by mass of a rubber component.",
    "5. The metal-rubber composite of claim 1, wherein the rubber is composed of a rubber composition containing ≥1 parts by mass of resorcin with respect to 100 parts by mass of a rubber component.",
    "6. The metal-rubber composite of claim 1, wherein the rubber composition contains said “(1) a metal salt of carboxylic acid” and the metal species in the metal salt of carboxylic acid (1) is bismuth or copper.",
    "7. The metal-rubber composite of claim 1, wherein the rubber composition contains the metal salt of carboxylic acid (1) and the carboxylic acid in the metal salt of carboxylic acid (1) is an aliphatic monocarboxylic acid or an aliphatic dicarboxylic acid.",
    "8. The metal-rubber composite of claim 7, wherein the carboxylic acid in the metal salt of carboxylic acid (1) is a C 2-20 saturated aliphatic monocarboxylic acid.",
    "9. The metal-rubber composite of claim 8, wherein the carboxylic acid in the metal salt of carboxylic acid (1) is 2-ethylhexanoic acid, neodecanoic acid, hexadecanoic acid or octadecanoic acid.",
    "10. The metal-rubber composite of claim 1, wherein the rubber composition contains said “(2) a compound” and that “M” in the compound (2) is bismuth or copper.",
    "11. The metal-rubber composite of claim 1, wherein the rubber composition contains the compound (2) and that “Z” in the compound (2) has a structure represented by the formula (z-1).",
    "12. The metal-rubber composite of claim 1, wherein the rubber composition contains the compound (2) and “(RCOO)” in the compound (2) is a residue of a C 2-20 saturated aliphatic monocarboxylic acid.",
    "13. The metal-rubber composite of claim 12, wherein (RCOO) in the compound (2) is a residue of 2-ethylhexanoic acid, a residue of neodecanoic acid, a residue of hexadecanoic acid or a residue of octadecanoic acid.",
    "14. A conveyor belt, characterized in that it has the metal-rubber composite of claim 1.",
    "15. A hose, characterized in that it has the metal-rubber composite of claim 1.",
    "16. A rubber track, characterized in that it has the metal-rubber composite of claim 1.",
    "17. A tire, characterized in that it has the metal-rubber composite of claim 1.",
    "18. The metal-rubber composite of claim 1, wherein a ratio (C 1 /C 2) of the total concentration (C 1) of at least one metal element selected from the group consisting of bismuth, antimony, silver, niobium, molybdenum, and zirconium in a region within 100 nm measured from an adhesion interface of the metal and the rubber toward the rubber side, with respect to the total concentration (C 2) of at least one metal element selected from the group consisting of bismuth, antimony, silver, niobium, molybdenum, and zirconium in a region between the 100 nm depth and the 200 nm depth, measured from the adhesion interface toward the rubber side, is 7.0 or larger.",
    "19. The metal-rubber composite of claim 18, wherein the at least one metal element is selected from the group consisting of molybdenum and zirconium.",
    "20. The metal-rubber composite of claim 3, wherein the at least one metal element is selected from the group consisting of molybdenum, zirconium and nickel."
  ],
  "description_excerpt": "The present invention relates to a metal-rubber composite, a conveyor belt, a hose, a rubber track, and a tire.\n\nA composite of a metal member and rubber (which will be referred to a “metal-rubber composite” hereinafter) is generally used in a rubber article requiring high strength such as a conveyor belt, a hose, a rubber track, a tire, and the like so that the rubber article, of which rubber is reinforced by the metal-rubber composite, exhibits high strength and durability as required. In this respect, the metal member and the rubber must be firmly attached to each other to make the metal-rubber composite reliably demonstrate high strength and durability over a long period.\n\nConventionally, an adhesion promoter is blended with rubber of a metal-rubber composite in order to effect direct adhesion of the metal and the rubber by vulcanization bonding. Common examples of the adhesion promoter include a cobalt salt of organic acid such as cobalt stearate, cobalt versatate, and the like.\n\nHowever, there exists concern about toxicity of cobalt salts of organic acids, whereby rubber not containing a cobalt salt has been in demand. To meet the demand, PTL 1 discloses an adhesion promoter composed of a specific metal salt, for rubber-metal adhesion.\n\nHowever, as a result of a keen study by the inventors of the present disclosure, it has been revealed that the adhesion promoter described in PTL 1 does not necessarily cause a satisfactory effect of promoting adhesion between metal and rubber. It is therefore necessary to further improve adhesion between metal and rubber without using a cobalt salt.",
  "cpc": [
    "C08K 5/098",
    "B60C 1/00",
    "B60C 9/00",
    "B62D 55/24",
    "B65G 15/34",
    "B65G 15/36",
    "C08K 3/06",
    "C08K 3/36",
    "C08K 9/02",
    "C08L 21/00",
    "C08L 9/06",
    "F16L 11/04",
    "F16L 11/08"
  ],
  "ipc": [
    "B62D 55/24",
    "B65G 15/36",
    "C08K 3/06",
    "C08K 3/36",
    "C08K 5/098",
    "C08K 9/02",
    "F16L 11/08"
  ],
  "assignees": [
    "Bridgestone Corp"
  ],
  "inventors": [
    "Kei Kimura",
    "Motoki AMIYA"
  ],
  "filing_date": "2020-08-21",
  "publication_date": "2025-09-30",
  "grant_date": "2025-09-30",
  "priority_date": "2019-09-30",
  "application_number": "US-202017642072-A",
  "family_id": "75269893",
  "cited_by_count": 0,
  "citations": [
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    "US20100168306A1",
    "JP2007186840A",
    "CN103804726A",
    "US9023928B2",
    "WO2016039375A1",
    "US20170253722A1",
    "US20190375911A1",
    "JP2017185938A"
  ]
}