Large-diameter heat-expanding microspheres and method for producing same

Patent metadata

Field	Value
Publication number	US-2018258248-A1
Application number	US-201515531586-A
Country	US
Kind code	A1
Filing date	Dec 2, 2015
Priority date	Dec 2, 2014
Publication date	Sep 13, 2018
Grant date	—

Abstract

Object:
To provide heat-expandable microspheres with which large-diameter foamed particles which are lightweight and have enhanced strength, cushioning properties, and the like can be formed.
Resolution Means:
Heat-expandable microspheres having a foaming agent encapsulated in an outer shell of a polymer, the heat-expandable microspheres having an average particle size (D50) before foaming of from 100 to 500 μm, and a coefficient of variation of a particle size distribution before foaming (logarithmic scale) of not greater than 15%.

First claim

1 . Heat-expandable microspheres having a foaming agent encapsulated in an outer shell of a polymer, the heat-expandable microspheres having an average particle size (D50) before foaming of from 100 to 500 μm, and a coefficient of variation of a particle size distribution before foaming (logarithmic scale) of not greater than 15%;
the outer shell of the polymer comprising from 25 to 100 mass % of a mixture of acrylonitrile and methacrylonitrile and from 0 to 75 mass % of at least one type of monomer selected from the group consisting of vinylidene chloride, acrylic acid esters, methacrylic acid esters, styrene, acrylic acid, methacrylic acid, and vinyl acetate;
the foaming agent comprising isopentane, isooctane, and isododecane; and
a foaming starting time being from 155 to 210° C.

2 . The heat-expandable microspheres according to claim 1 , wherein an average particle size of foamed particles formed by thermally expanding the heat-expandable microspheres is from 200 to 1000 μm.

3 . (canceled)

4 . (canceled)

5 . (canceled)

6 . A paint or molded product comprising the heat-expandable microspheres according to claim 1 .

7 . A laminate comprising a coating film containing foamed particles formed by thermally expanding the heat-expandable microspheres according to claim 1 , or a molded product comprising the foamed particles.

8 . (canceled)

Assignees

• Kureha Corp

Inventors

• Ejiri Tetsuo
• Hasegawa Tomohisa
• Sato Daisuke
• Satou Kazunori
• Matsuzaki Mitsuhiro

Classifications

• C08J9/224

  Surface treatment · CPC title

• C08J2433/08

  Homopolymers or copolymers of acrylic acid esters · CPC title

• C08J2431/04

  Homopolymers or copolymers of vinyl acetate · CPC title

• C09K3/00

  Materials not provided for elsewhere · CPC title

• C08J2207/00

  Foams characterised by their intended use · CPC title