Method for producing rubber composition and rubber composition

Patent metadata

Field	Value
Publication number	US-10087293-B2
Application number	US-201715685635-A
Country	US
Kind code	B2
Filing date	Aug 24, 2017
Priority date	Oct 17, 2013
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

A method for producing a rubber composition include a mixing step, a drying step, and a dispersion step. In the mixing step, an aqueous solution that includes at least one of oxycellulose fibers and cellulose nanofibers is mixed with rubber latex to obtain a first mixture. In the drying step, the first mixture is dried to obtain a second mixture. In the dispersion step, the second mixture is tight-milled using an open roll to obtain a rubber composition. The rubber composition does not include an aggregate that includes at least one of the oxycellulose fibers and the cellulose nanofibers, and has a diameter of 0.1 mm or more.

First claim

What is claimed is:

1. A rubber composition, comprising:
at least one of oxycellulose fibers and cellulose nanofibers that are dispersed in the rubber composition, such that all of the at least one of oxycellulose fibers and cellulose nanofibers are in an untangled state,

the rubber composition obtained by a method comprising:
a mixing step that mixes an aqueous solution that includes the at least one of oxycellulose fibers and cellulose nanofibers with rubber latex to obtain a first mixture;
a drying step that dries the first mixture to obtain a second mixture; and
a dispersion step that tight-mills the second mixture using an open roll to obtain the rubber composition,
wherein the mixing step includes repeating the following steps (1) to (4) a plurality of times:
(1) mixing the aqueous solution and the rubber latex using the open roll to obtain a mixture;
(2) removing the mixture from the open roll when the viscosity of the mixture has increased;
(3) after step (2), reducing a roll distance of the open roll; and
(4) after step (3), supplying the mixture to the open roll again,

wherein the mixing step obtains the first mixture in which at least one of the oxycellulose fibers and the cellulose nanofibers enter the space between rubber microparticles in the rubber latex by repeatedly performing the steps (1) to (4).

2. A rubber composition comprising rubber, and at least one of oxycellulose fibers and cellulose nanofibers that are dispersed in the rubber, such that all of the at least one of oxycellulose fibers and cellulose nanofibers are in an untangled state, the rubber composition not including an aggregate that includes at least one of the oxycellulose fibers and the cellulose nanofibers, and has a diameter of 0.1 mm or more, the rubber composition obtained by a method comprising:
a mixing step that mixes an aqueous solution that includes the at least one of oxycellulose fibers and cellulose nanofibers with rubber latex to obtain a first mixture;
a drying step that dries the first mixture to obtain a second mixture; and
a dispersion step that tight-mills the second mixture using an open roll to obtain the rubber composition,
wherein the mixing step includes repeating the following steps (1) to (4) a plurality of times:
(1) mixing the aqueous solution and the rubber latex using the open roll to obtain a mixture;
(2) removing the mixture from the open roll when the viscosity of the mixture has increased;
(3) after step (2), reducing a roll distance of the open roll; and
(4) after step (3), supplying the mixture to the open roll again,

wherein the mixing step obtains the first mixture in which at least one of the oxycellulose fibers and the cellulose nanofibers enter the space between rubber microparticles in the rubber latex by repeatedly performing the steps (1) to (4).

3. The rubber composition as defined in claim 2 , comprising at least one of the oxycellulose fibers and the cellulose nanofibers in an amount of 0.1 to 60 parts by mass based on 100 parts by mass of the rubber.

Assignees

• Nissin Kogyo Kk
• Univ Shinshu

Inventors

• Kawamoto Keiichi
• Ueki Hiroyuki
• Noguchi Toru
• Niihara Kenichi

Classifications

• B29C43/24

  Calendering · CPC title

• C08J2315/00

  Characterised by the use of rubber derivatives (C08J2311/00, C08J2313/00 takes precedence) · CPC title

• B29K2007/00

  Use of natural rubber as moulding material · CPC title

• B29K2001/00

  Use of cellulose, modified cellulose or cellulose derivatives, e.g. viscose, as moulding material · CPC title

• C08K7/02

  Fibres or whiskers · CPC title