Polyurea crosslinked particles for transport device member, sliding member and method of preparing polyurea crosslinked particles for transport device member

Patent metadata

Field	Value
Publication number	US-9745532-B2
Application number	US-201615171479-A
Country	US
Kind code	B2
Filing date	Jun 2, 2016
Priority date	Jun 11, 2015
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

Polyurea crosslinked particles for a transport device member are provided that have high acid resistance, increase long-term retainability when included in a coating film, and are capable of maintaining a high sliding property for a long time. The polyurea crosslinked particles for a transport device member are particles formed of reactants of a self-emulsifying isocyanate having two or more isocyanate groups and a non-self-emulsifying isocyanate having two or more isocyanate groups and having a ring structure in the presence of water and a crosslink density thereof is 1×10 −4 mol/g or more.

First claim

What is claimed is:

1. Polyurea crosslinked particles for a transport device member that are particles formed of reactants of a self-emulsifying isocyanate having two or more isocyanate groups and a non-self-emulsifying isocyanate having two or more isocyanate groups and having a ring structure in the presence of water, and the particles having no urethane structure,
wherein a crosslink density is 1×10 −4 mol/g or more.

2. The polyurea crosslinked particles for a transport device member according to claim 1 , wherein any of the self-emulsifying isocyanate and the non-self-emulsifying isocyanate includes three or more isocyanate groups.

3. The polyurea crosslinked particles for a transport device member according to claim 1 , wherein the self-emulsifying isocyanate has a content ratio that is 30 to 90 mass % when a total of the isocyanates is set as 100 mass %.

4. The polyurea crosslinked particles for a transport device member according to claim 2 , wherein the self-emulsifying isocyanate has a content ratio that is 30 to 90 mass % when a total of the isocyanates is set as 100 mass %.

5. A sliding member in which a lubricant retaining coating film is formed on a surface of a sliding portion, and the lubricant retaining coating film includes a plurality of the polyurea crosslinked particles for a transport device member according to claim 1 and a binder resin for binding the polyurea crosslinked particles to each other.

6. The sliding member according to claim 5 ,
wherein the polyurea crosslinked particles in the lubricant-retaining coating film have a content ratio that is 60 mass % or less when the lubricant-retaining coating film is set as 100 mass %.

7. The sliding member according to claim 6 ,
wherein the polyurea crosslinked particles in the lubricant-retaining coating film have a content ratio that is 5 to 30 mass % when the lubricant-retaining coating film is set as 100 mass %.

8. A method of preparing polyurea crosslinked particles for a transport device member according to claim 1 , comprising:
reacting a self-emulsifying isocyanate having two or more isocyanate groups and a non-self-emulsifying isocyanate having two or more isocyanate groups and having a ring structure in the presence of water so that the particles have a crosslink density of 1×10 −4 mol/g or more and the particles having no urethane structure.

Assignees

• Honda Motor Co Ltd
• Negami Chemical Ind Co Ltd

Inventors

• Sakurai Tasuku
• Nishita Keiko

Classifications

• C10N2050/02

  dissolved or suspended in a carrier which subsequently evaporates to leave a lubricant coating · CPC title

• C08G18/48

  Polyethers · CPC title

• C09D175/02

  Polyureas · CPC title

• C08G18/755

  and at least one isocyanate or isothiocyanate group linked to a secondary carbon atom of the cycloaliphatic ring, e.g. isophorone diisocyanate · CPC title

• C10N2050/015

  Dispersions of solid lubricants · CPC title