Tire rubber composition and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-10501601-B2
Application number	US-201414893307-A
Country	US
Kind code	B2
Filing date	May 28, 2014
Priority date	May 31, 2013
Publication date	Dec 10, 2019
Grant date	Dec 10, 2019

Abstract

The present invention provides a tire rubber composition prepared by mixing at least one rubber component selected from natural rubbers and synthetic diene rubbers (A), a filler including an inorganic filler (B), a silane coupling agent (C) and a thiosemicarbazone derivative (D), and provides a production method for a tire rubber composition, wherein the tire rubber composition is kneaded in plural stages, and in the first stage of kneading, the rubber component (A), all or part of the inorganic filler (B), all or part of the silane coupling agent (C), and the thiosemicarbazone derivative (D) are kneaded, therefore providing a tire rubber composition having improved reactivity between the coupling agent and the rubber component and excellent in low-heat-generation property and a production method for the composition.

First claim

The invention claimed is:

1. A tire rubber composition prepared by mixing at least one rubber component comprising styrene-butadiene copolymer rubber (A), a filler comprising an inorganic filler (B), a silane coupling agent (C) and a thiosemicarbazone derivative (D),
wherein the thiosemicarbazone derivative (D) is acetonethiosemicarbazone.

2. The tire rubber composition according to claim 1 , wherein the silane coupling agent (C) is at least one compound selected from the group consisting of compounds represented by the following general formulae (II) to (IV):
(R 1 O) 3-p (R 2 ) p Si—R 3 —S a —R 3 —Si(OR 1 ) 3-r (R 2 ) r   (II)

wherein plural R 1 's, if any, may be the same or different and each represent a substituent selected from a linear, cyclic or branched alkyl group having from 1 to 8 carbon atoms, a linear or branched alkoxylalkyl group having from 2 to 8 carbon atoms, and a hydrogen atom; plural R 2 's, if any, may be the same or different and each represent a linear, cyclic or branched alkyl group having from 1 to 8 carbon atoms; plural leis, if any, may be the same or different and each represent a linear or branched alkylene group having from 1 to 8 carbon atoms; a indicates from 2 to 6 as a mean value; and p and r may be the same or different and each indicate from 0 to 3 as a mean value, provided that both p and r are not 3 at the same time;

wherein R 4 represents a monovalent group selected from —Cl, —Br, R 9 O—, R 9 C(═O)O—, R 9 R 10 C═NO—, R 9 R 10 CNO—, R 9 R 10 N—, and —(OSiR 9 R 10 ) h (OSiR 9 R 10 R 11 ) (where R 9 , R 10 and R 11 each represent a hydrogen atom or a monovalent hydrocarbon group having from 1 to 18 carbon atoms; and h indicates from 1 to 4 as a mean value); R 5 represents R 4 , a hydrogen atom, or a monovalent hydrocarbon group having from 1 to 18 carbon atoms; R 6 represents R 4 , R 5 , a hydrogen atom, or a group —[O(R 12 O) j ] 0.5 (where R 12 represents an alkylene group having from 1 to 18 carbon atoms; and j indicates an integer of from 1 to 4); R 7 represents a divalent hydrocarbon group having from 1 to 18 carbon atoms; R 8 represents a monovalent hydrocarbon group having from 1 to 18 carbon atoms; x, y and z each indicate a number satisfying the relationship of x+y+2z=3, 0≤x≤3, 0≤y≤2, 0≤z≤1;
(R 13 O) 3-s (R 14 ) s Si—R 15 —S k —R 16 —S k —R 15 —Si(OR 13 ) 3-t (R 14 ) t   (IV)

wherein plural R 13 's, if any, may be the same or different and each represent a linear, cyclic or branched alkyl group having from 1 to 8 carbon atoms, a linear or branched alkoxylalkyl group having from 2 to 8 carbon atoms, or a hydrogen atom; plural R 14 's, if any, may be the same or different and each represent a linear, cyclic or branched alkyl group having from 1 to 8 carbon atoms; plural R 15 's, if any, may be the same or different and each represent a linear or branched alkylene group having from 1 to 8 carbon atoms; V represents a divalent group selected from general formulae (—S—R 17 —S—), (—R 18 —S m1 —R 19 —) and (—R 20 —S m2 —R 21 —S m3 —R 22 —) (where R 17 to R 22 each represent a divalent substituent selected from a divalent hydrocarbon group, a divalent aromatic group and a divalent organic group containing a hetero element except sulfur and oxygen, each having from 1 to 20 carbon atoms; m1, m2 and m3 each indicate from 1 to less than 4 as a mean value); plural k's may be the same or different and each indicate from 1 to 6 as a mean value; and s and t each indicate from 0 to 3 as a mean value, provided that both s and t are not 3 at the same time.

3. The tire rubber composition according to claim 2 , wherein the silane coupling agent (C) is a compound represented by the general formula (II).

4. The tire rubber composition according to claim 1 , wherein the inorganic filler (B) is silica.

5. The tire rubber composition according to claim 1 , wherein the filler contains carbon black.

6. The tire rubber composition according to claim 1 , wherein the inorganic filler (B) accounts for 40% by mass or more in the filler.

7. A tire using the tire rubber composition of claim 1 .

8. The tire rubber composition according to claim 4 , wherein the tire rubber composition is kneaded in plural stages, and
all of the rubber component (A), all or part of the silica, all or part of the silane coupling agent (C), and all of the thiosemicarbazone derivative (D) are kneaded in a first stage of kneading, or
in the first stage of kneading, as a first master batch kneading stage, all of the rubber component (A), all or part of the silica, and all or part of the silane coupling agent (C) are kneaded, spontaneously cooled and aged, and then as an intermediate stage, all of the thiosemicarbazone derivative (D) is added and further kneaded.

9. The tire rubber composition according to claim 3 , wherein
the inorganic filler (B) is silica,
the filler comprises carbon black,
the filler is incorporate in an amount of from 20 to 150 parts by mass relative to 100 parts by mass of the rubber component (A),
the inorganic filler (B) is incorporated in an amount of from 20 to 120 parts by mass relative to 100 parts by mass of the rubber component (A),
the thiosemicarbazone derivative (D) is incorporated in an amount of from 0.05 to 15 parts by mass relative to 100 parts by mass of the rubber component (A),
a ratio by mass of the thiosemicarbazone derivative (D) to the silane coupling agent (C) in the tire rubber composition is from 0.02 to 1.0, and
a ratio by mass of the silane coupling agent (C) to the inorganic filler (B) in the tire rubber composition is from 0.01 to 0.6.

10. The tire rubber composition according to claim 9 , wherein
the inorganic filler (B) is incorporated in an amount of from 30 to 100 parts by mass relative to 100 parts by mass of the rubber component (A),
the thiosemicarbazone derivative (D) is incorporated in an amount of from 0.2 to 10 parts by mass relative to 100 parts by mass of the rubber component (A),
the ratio by mass of the thiosemicarbazone derivative (D) to the silane coupling agent (C) in the tire rubber composition is from 0.04 to 0.5, and
the ratio by mass of the silane coupling agent (C) to the inorganic filler (B) in the tire rubber composition is from 0.03 to 0.2.

Assignees

• Bridgestone Corp

Inventors

• Yukimura Noriaki

Classifications

• C08K3/04

  Carbon · CPC title

• C08L91/00

  Compositions of oils, fats or waxes; Compositions of derivatives thereof · CPC title

• C08K3/36

  Silica · CPC title

• C08K5/405 Primary

  Thioureas; Derivatives thereof · CPC title

• B60C1/0016

  Compositions of the tread · CPC title