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Process for preparing polymer emulsion particles having pores

Assignee: Mitsui Chemicals Inc
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Filing: 1989-12-27
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Granted: —
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Expires: 2009-12-27
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Abstract

Abstract A process for preparing polymer emulsion particles having pores therein, an outside diameter D of 0.1 to 5.0 mu , an inside diameter d of 0.05 to 4.0 mu , and a ratio (d/D) of 0.1 to 0.9 in dry condition, comprising the steps of forming core-shell emulsion particles from specific monomers by two-emulsion polymerizations, and swelling the core of the particles with water by hydrolyzing the vinyl acetate part of polymer (A), thereby inducing the hydroxyl groups therein, e.g., using an acidic material or a basic material at 50 to 100 DEG C. The particles when use as a pigment in coating compositions provide excellent converage rate, brightness, gloss and water resistance.

Inventors

  • 👤 Futoshi Hoshino
  • 👤 Takeshi Yanagihara
  • 👤 Makoto Nakano

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-06 15:13
CPC Classifications
C; C08; C08F; C08F216/00; D; D21; D21H; D21H19/00; D21H19/36; D21H19/44; D21H19/56; D21H19/60; C08F2/00; C08F2/12; C08F2/16; C08F2/22; C08F263/00; C08F263/02; C08F263/04; C08F291/00; C08F8/00; C08F8/44; D21H19/58; C08F2810/00; C08F2810/50

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 150 words
A process for preparing polymer emulsion parti­cles having pores therein, an outside diameter D of 0.1 to 5.0 µ, an inside diameter d of 0.05 to 4.0 µ, and a ratio (d/D) of 0.1 to 0.9 in a dry condition, comprising the steps of: (I) forming a polymer (A) by emulsion polymerization of 2 to 80 parts by weight of vinyl acetate and 98 to 20 parts by weight of another vinyl monomer (a) which is copolymerizable therewith; (II) forming core-shell emulsion particles whose shell comprised of a polymer (B) by the emulsion polymerization of 95 to 30 parts by weight of a vinyl monomer (b) while using 5 to 70 parts by weight by the polymer (A) as core particles; and (III) swelling the core of the particles with water by hydrolyzing the acetate groups of the vinyl acetate moieties of polymer (A), thereby forming the hydroxyl groups therein.
Claim 2
Dependent Claim 150 words
A process for preparing polymer emulsion parti­cles having pores therein, an outside diameter D of 0.1 to 5.0 µ, an inside diameter d of 0.05 to 4.0 µ, and a ratio (d/D) of 0.1 to 0.9 in a dry condition, comprising the steps of: (I) forming a polymer (A) by emulsion polymerization of 2 to 80 parts by weight of vinyl acetate and 98 to 20 parts by weight of another vinyl monomer (a) which is copolymerizable therewith; (II) forming core-shell emulsion particles whose shell comprised of a polymer (B) by the emulsion polymerization of 95 to 30 parts by weight of a vinyl monomer (b) while using 5 to 70 parts by weight by the polymer (A) as core particles; and (III) swelling the core of the particles with water by hydrolyzing the acetate groups of the vinyl acetate moieties of polymer (A), thereby forming the hydroxyl groups therein.
Claim 3
Dependent Claim 28 words
The process of claim 1 wherein vinyl monomer (a) is selected from the group consisting of (meth)acrylic esters, aromatic vinyl monomers, vinyl cyano monomers and halogenated vinyl monomers.
Claim 4
Dependent Claim 28 words
The process of claim 1 wherein vinyl monomer (b) is selected from the group consisting of aromatic vinyl monomers, (meth)acrylic ester, vinyl cyano monomers and halogenated vinyl monomers.
Claim 5
Dependent Claim 14 words
The process of claim 1 wherein vinyl monomer (b) is an aromatic vinyl compound.
Claim 6
Dependent Claim 26 words
The process of claim 1 wherein the amount of vinyl acetate used is 5 to 50 parts by weight of monomers used to produce polymer (A).
Claim 7
Dependent Claim 17 words
The process of claim 1 wherein the glass transi­tion temperature of polymer (B) is at least 50°C.
Claim 8
Dependent Claim 23 words
The process of claim 1 wherein the pH of the thus-produced emulsion is not less than pH 8 or more than pH 3.
Claim 9
Dependent Claim 16 words
The process of claim 1 wherein the hydrolysis is conducted at temperature of 70 to 98°C.
Claim 10
Dependent Claim 26 words
The process of claim 1 wherein the particle have an outside diameter D of 0.3 to 1.0 µ and a ratio (d/D) of 0.2 to 0.8.
Claim 11
Dependent Claim 130 words
The process of claim 1 comprising the step of: (I) forming a polymer (A) by emulsion polymerization of 5 to 50 parts by weight of vinyl acetate and 95 to 50 parts by weight of the vinyl monomer (a) selected from the group consisting of (meth)acrylic esters, aromatic vinyl monomers, vinyl cyano monomers and halogenated vinyl monomers. (II) forming core-shell emulsion particles whose shell is comprised of polymer (B) by the emulsion polymerization of 95 to 30 parts by weight of a vinyl monomer (b) selected from the group consisting of aromatic vinyl monomers, (meth)acrylic ester, vinyl cyano monomers and halogenated vinyl monomers. (III) swelling the core of the particles with water by hydrolyzing the acetate groups of the vinyl acetate moieties of polymer (A), thereby forming hydroxyl groups therein.
Claim 12
Dependent Claim 122 words
A process for preparing polymer emulsion particles having pores therein, an outside diameter D of 0.1 to 5.0 µ, an inside diameter d of 0.05 to 4.0 µ, and a ratio (d/D) of 0.1 to 0.9 in a dry condition, which comprises the step of hydrolyzing the acetate moieties of a particulate vinyl acetate emulsion polymerized copolymer having a 2 to 80 parts by weight vinyl acetate content, which copolymer particles are the cores of core-shell particles and constitute 5 to 70 parts by weight of thereof, the shell of the particles being a polymer which is resistant to hydrolysis of a vinyl monomer emulsion polymerized onto the surface of the copolymre particles, thereby swelling the core particles and forming pores therein.
Claim 13
Dependent Claim 122 words
A process for preparing polymer emulsion particles having pores therein, an outside diameter D of 0.1 to 5.0 µ, an inside diameter d of 0.05 to 4.0 µ, and a ratio (d/D) of 0.1 to 0.9 in a dry condition, which comprises the step of hydrolyzing the acetate moieties of a particulate vinyl acetate emulsion polymerized copolymer having a 2 to 80 parts by weight vinyl acetate content, which copolymer particles are the cores of core-shell particles and constitute 5 to 70 parts by weight of thereof, the shell of the particles being a polymer which is resistant to hydrolysis of a vinyl monomer emulsion polymerized onto the surface of the copolymre particles, thereby swelling the core particles and forming pores therein.

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