Rubber composition

Patent metadata

Field	Value
Publication number	US-2016289398-A1
Application number	US-201415035346-A
Country	US
Kind code	A1
Filing date	May 12, 2014
Priority date	Nov 11, 2013
Publication date	Oct 6, 2016
Grant date	—

Abstract

A rubber composition obtained by dry-mixing a rubber wet masterbatch A containing a carbon black A having a nitrogen adsorption specific: surface area (N 2 SA) of NA (m 2 /g) with a rubber wet masterbatch B containing a carbon black B having a nitrogen adsorption specific surface area (N 2 SA) of NB (m 2 /g),
wherein the content ratio of the rubber wet masterbatch A to the rubber wet masterbatch B is from 5/95 to 40/60, and
when the content proportion of the carbon black A in the rubber wet masterbatch A is represented by LA, and that of the carbon black B in the rubber wet masterbatch B is represented by LB, the specific expressions are satisfied.

First claim

1 . A rubber composition obtained by dry-mixing a rubber wet masterbatch A containing a carbon black A having a nitrogen adsorption specific surface area (N 2 SA) of NA (m 2 /g) with a rubber wet masterbatch B containing a carbon black B having a nitrogen adsorption specific surface area (N 2 SA) of NB (m 2 /g),
wherein the content ratio of the rubber wet masterbatch A to the rubber wet masterbatch B is from 5/95 to 40/60, and when the content proportion of the carbon black A in the rubber wet masterbatch A is represented by LA, and that of the carbon black B in the rubber wet masterbatch B is represented by LB, the following expressions (1) and (2) are satisfied:
NA>NB   (1), and

1800≦ NA>LA−NB×LB< 7000   (2)

wherein LA and LB each represent 100דthe content of the carbon black in the rubber wet masterbatch”/“content of a rubber component in the rubber wet masterbatch”.

2 . The rubber composition according to claim 1 , wherein the rubber component which the rubber wet masterbatch A and the rubber wet masterbatch B each contain is at least one selected from the group consisting of natural rubber, polystyrene-butadiene rubber, and polybutadiene rubber.

3 . The rubber composition according to claim 1 , wherein when the total amount of the rubber component which the rubber wet masterbatch A contains and the rubber component which the rubber wet masterbatch B contains is regarded as 100 parts by mass, natural rubber or the component natural rubber is contained in an amount of 80 parts or more by mass.

4 . The rubber composition according to claim 1 , wherein the rubber wet masterbatch A and the rubber wet masterbatch B are each obtained through a step (α) of using at least the carbon black, a dispersing solvent and a rubber latex solution as raw materials, and dispersing at least the carbon black into the dispersing solvent to produce a carbon-black-containing slurry solution, a step (β) of mixing the carbon-black-containing slurry solution with the rubber latex solution to produce a carbon-black-containing rubber latex solution, and a step (γ) of solidifying/drying the carbon-black-containing rubber latex solution; and
the step (α) is a step (α−(a)) in which when the carbon black is dispersed into the dispersing solvent, at least one portion of the rubber latex solution is added thereto, thereby producing the carbon-black-containing slurry solution in which rubber latex particles adhere to the carbon black, and
the step (β) is a step (β−(a)) of mixing the carbon-black-containing slurry solution, in which the rubber latex particles adhere to the carbon black, with the rest of the rubber latex solution to produce the carbon-black-containing rubber latex solution in which rubber latex particles adhere to the carbon black.

5 . A pneumatic tire, comprising a ply topping rubber obtained using the rubber composition recited in claim 1 .

6 . A pneumatic tire, comprising a tread rubber obtained using the rubber composition recited in claim 1 .

7 . A pneumatic tire, comprising a bead filler rubber obtained using the rubber composition recited in claim 1 .

Assignees

• Toyo Tire & Rubber Co

Inventors

• Tanaka Makoto
• Nomura Kenji
• Minouchi Norio

Classifications

• Y02T10/86

  Optimisation of rolling resistance, e.g. weight reduction · CPC title

• C08J3/226 Primary

  using a polymer as a carrier · CPC title

• C08J2307/00

  Characterised by the use of natural rubber · CPC title

• C08J2347/00

  Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds; Derivatives of such polymers (C08J2345/00 takes precedence; of conjugated diene rubbers C08J2309/00 - C08J2321/00) · CPC title

• C08K2201/006

  Additives being defined by their surface area · CPC title