Method for producing latex composition

Patent metadata

Field	Value
Publication number	US-11067145-B2
Application number	US-201716086799-A
Country	US
Kind code	B2
Filing date	Mar 16, 2017
Priority date	Mar 23, 2016
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

A method for producing a composition containing a latex of a nitrile rubber of α,β-ethylenically unsaturated nitrile monomer unit of 8 to 60 wt % content, and an iodine value of 120 or less, an isothiazoline-based compound represented by formula (1), and a benzisothiazoline-based compound represented by formula (2), both in a content of 26 ppm by weight or more to the rubber, wherein adding both compounds to the latex at 2,000 ppm by weight/min or less, at 50° C. or lower, and the compounds in an aqueous state having 0.1 to 40 wt % concentration.

formula (1), R 1 and formula (2), R 4 represents a hydrogen atom, or a substituted or unsubstituted organic group; wherein formula (1) R 2 and R 3 represent a hydrogen atom, a halogen atom, or an substituted organic group; and formula (2), R 5 represent a hydrogen atom, or an substituted organic group, and an integer “n” of 0 to 4.

First claim

The invention claimed is:

1. A method for producing a latex composition comprising a latex of a nitrile rubber containing an α,β-ethylenically unsaturated nitrile monomer unit in a content of 8 to 60 wt %, and having an iodine value of 120 or less, an isothiazoline-based compound represented by the following general formula (1) and a benzisothiazoline-based compound represented by the following general formula (2), the content of the isothiazoline-based compound being 26 ppm by weight or more and the content of the benzisothiazoline-based compound being 26 ppm by weight or more, with respect to the nitrile rubber,
wherein the method comprises an addition step of adding the isothiazoline-based compound and the benzisothiazoline-based compound being each in a state of an aqueous solution having a concentration of 0.1 to 40 wt % to the latex of the nitrile rubber under the condition that the latex of the nitrile rubber is in a state at a temperature of 50° C. or lower, and
the isothiazoline-based compound and the benzisothiazoline-based compound are added in such a way that the addition rate in the addition step is 2,000 ppm by weight/min or less in terms of the total addition rate of the isothiazoline-based compound and the benzisothiazoline-based compound,

wherein, in the general formula (1), R 1 represents a hydrogen atom, or a substituted or unsubstituted organic group, and R 2 and R 3 each independently represent a hydrogen atom, a halogen atom, or a substituted or unsubstituted organic group;

wherein, in the general formula (2), R 4 represents a hydrogen atom, or a substituted or unsubstituted organic group, R 5 each independently represent a hydrogen atom, or a substituted or unsubstituted organic group, and “n” represents an integer of 0 to 4.

2. The method for producing a latex composition according to claim 1 , wherein in the addition step, the isothiazoline-based compound and the benzisothiazoline-based compound are added in a state of a composite aqueous solution having a total concentration of the isothiazoline-based compound and the benzisothiazoline-based compound of 0.1 to 40 wt % to the latex of the nitrile rubber.

3. The method for producing a latex composition according to claim 1 , wherein the pH of the latex of the nitrile rubber is less than 12.

4. The method for producing a latex composition according to claim 1 , wherein the nitrile rubber contains a carboxyl group-containing monomer unit.

5. A method for producing a nitrile rubber composition, comprising a step of coagulating the latex composition obtained by the method according to claim 1 .

6. A method for producing a resin-containing latex composition, comprising a step of mixing the latex composition obtained by the method according to claim 1 , and a thermosetting resin with each other.

7. A method for producing a friction material, comprising a step of making the resin-containing latex composition obtained by the method according to claim 6 attached to or mixed with a base material.

Assignees

• Zeon Corp

Inventors

• Oyama Fuminari
• Watanabe Yasuaki

Classifications

• C08K5/46 Primary

  with oxygen or nitrogen in the ring · CPC title

• C08L15/00

  Compositions of rubber derivatives (C08L11/00, C08L13/00 take precedence) · CPC title

• C08K5/47

  Thiazoles · CPC title

• C08K5/0058

  Biocides; (macromolecular substances as carriers for biocide material A01N25/10) · CPC title

• C08L101/00

  Compositions of unspecified macromolecular compounds · CPC title