US 12,065,568 B2
Porous spherical silicone rubber particles, porous silicone composite particles, and method for producing these particles
Takahito Oki, Annaka (JP); Yoshinori Inokuchi, Annaka (JP); Shunji Aoki, Annaka (JP); and Tsuneo Kimura, Annaka (JP)
Assigned to SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Appl. No. 17/273,900
Filed by SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
PCT Filed Aug. 30, 2019, PCT No. PCT/JP2019/034132
§ 371(c)(1), (2) Date Mar. 5, 2021,
PCT Pub. No. WO2020/050168, PCT Pub. Date Mar. 12, 2020.
Claims priority of application No. 2018-166492 (JP), filed on Sep. 6, 2018.
Prior Publication US 2021/0238422 A1, Aug. 5, 2021
Int. Cl. C08L 83/06 (2006.01); C08J 3/12 (2006.01); C08J 9/26 (2006.01)
CPC C08L 83/06 (2013.01) [C08J 3/12 (2013.01); C08J 9/26 (2013.01); C08J 2383/05 (2013.01); C08J 2383/06 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method for preparing spherical porous silicone rubber particles having pores in the interior or on the surface thereof, comprising the steps of:
(i) obtaining a W/O (inner water phase/oil phase) emulsion consisting of an inner water phase component and an oil phase component composed of a curable liquid silicone composition,
(ii) obtaining a W/O/W (inner water phase/oil phase/outer water phase) emulsion consisting of the W/O emulsion obtained in step (i) and an outer water phase component using a surfactant (ii), the content of the surfactant (ii) being 0.01 to 10 parts by weight per 100 parts by weight of the W/O emulsion,
(iii) curing the curable liquid silicone composition constituting the oil phase in the W/O/W emulsion obtained in step (ii) in the presence of a catalyst, for yielding a water dispersion of spherical porous silicone rubber particles, and
(iv) removing water in the outer phase and water in the spherical porous silicone rubber particles from the water dispersion of spherical porous silicone rubber particles obtained in step (iii).