The present invention provides a method for producing a rubber composition containing a rubber component (A) of at least one selected from natural rubbers and synthetic dienic rubbers, an inorganic filler (B), a silane coupling agent (C) and an acidic compound (D), wherein the rubber composition is kneaded in multiple stages, and in the final stage of kneading, the acidic compound (D) is added, and the highest temperature of the rubber composition in the final stage of kneading is from 60 to 120°C. The production method enables production of a rubber composition having a low-heat-generation property while successfully preventing the coupling function activity of the silane coupling agent from lowering.
RUBBER COMPOSITION MANUFACTURING METHOD, RUBBER COMPOSITION, AND PNEUMATIC TIRE USING SAME
申请人:Bridgestone Corporation
公开号:EP2799467A1
公开(公告)日:2014-11-05
The present invention provides a method for producing a rubber composition provided by compounding a rubber component (A) comprising at least one selected from natural rubbers and synthetic diene rubbers, a filler containing an inorganic filler (B), a silane coupling agent (C), and at least one vulcanization accelerator (D) selected from specific compounds, wherein the rubber composition is kneaded in a plurality of stages and wherein, in the first stage (X) of kneading, a portion (A') of the rubber component (A), all or a portion of the inorganic filler (B), all or a portion of the silane coupling agent (C), and all or a portion of the vulcanization accelerator (D) are added and kneaded, and in or after the second stage of kneading, the residual portion (A") of the rubber component (A) is added and kneaded, and the method for producing a rubber composition enables production of a rubber composition capable of suitably having a low-heat-generation property by further improving the coupling function activity of the silane coupling agent therein.
The present invention provides a tire improved in the run flat durability, having at least one member selected from the group consisting of a side reinforcing rubber layer and a bead filler using a rubber composition having a tensile stress at 50% elongation at 180°C (M50) of 6.2 MPa or more as a vulcanized rubber physical property.
This disclosure is to provide a rubber composition excellent in low loss property and wear resistance without deteriorating the processability. The rubber composition of this disclosure contains a rubber component having a diene-based polymer, a silica, and a glycerin fatty acid ester composition, wherein: the diene-based polymer has 3 or more modified functional groups capable of interacting with the silica merely within a range of 1/4 of an entire chain length from a terminal, and has at least one monomer structural unit of a diene-based polymer among the modified functional groups; and the glycerin fatty acid ester composition has a glycerin fatty acid monoester and a glycerin fatty acid diester of C8 to C28 fatty acids, and a content of the glycerin fatty acid ester composition is 0.5 to 15 parts by mass per 100 parts by mass of the rubber component.
As a rubber composition for tire excellent in processability, low loss property, breaking resistance and wear resistance, this disclosure provides a rubber composition for tire obtainable by a method for producing a rubber composition comprising: (a) preparing a preliminary composition by preparing a first mixture containing all of or a part of a diene based rubber (A), a silica (B), a silane coupling agent (C) and an activator (D), and containing a glycerin fatty acid ester (E), and kneading the first mixture; and (b) preparing the rubber composition by adding a vulcanizing agent (F) into the preliminary composition to prepare a second mixture, and kneading the second mixture, wherein: the glycerin fatty acid ester (E) is an ester of a glycerin and two or more fatty acids, a fatty acid component which is the most among the two or more fatty acids constituting the glycerin fatty acid ester being 10 to 90 mass% of all the fatty acids.