Method for the Production of Resin Particles

• US 20080199500A1
• Filed: 09/13/2005
• Published: 08/21/2008
• Est. Priority Date: 12/07/2004
• Status: Active Grant

• Current Assignee: Daicel-Evonik Ltd. (Daicel Corporation)
• Original Assignee: Daicel-Degussa Limited
• Inventors: Okumura, Arimichi
• Granted Patent: US 8,148,357 B2
• Time in Patent Office: Days
• US Class Current: 424/401
• CPC Class Codes: A61K 8/88 Polyamides
• CPC Class Codes: A61Q 19/00 Preparations for care of the skin
• CPC Class Codes: C08J 2377/00 Characterised by the use of polyamides obtained by reactions forming a carboxylic amide link in the main chain of polyhydrazides C08J2379/06; of polyamide-imides or polyamide acids C08J2379/08; Derivatives of such polymers
• CPC Class Codes: C08J 3/16 by coagulating dispersions C08J3/122 takes precedence

Abstract

Resin particles are produced by adding a liquid material having a boiling point of 100° C. or higher to an aqueous dispersion of resin particles to yield a mixture, recovering a wet cake from the mixture by filtration, and drying the wet cake. A water-soluble material is preferably used as the liquid material. The liquid material may also be at least one compound selected from compounds listed in The Japanese Standards of Cosmetic Ingredients, The Japanese Cosmetic Ingredients Codex, The Pharmacopoeia of Japan, and The Japan'"'"'s Specifications and Standards for Food Additives. According to this method, there are provided resin particles which are resistant to coagulation upon drying and are satisfactorily dispersible in other materials.

Claims

1. A method for the production of resin particles, comprising the steps of adding a liquid material having a boiling point of 100°

C. or higher to an aqueous dispersion of resin particles to yield a mixture, recovering a wet cake from the mixture by filtration, and drying the wet cake to thereby yield resin particles.

2. The method for the production of resin particles according to claim 1, wherein the liquid material comprises a water-soluble material.

3. The method for the production of resin particles according to claim 1, wherein the liquid material comprises at least one compound selected from compounds listed in The Japanese Standards of Cosmetic Ingredients, The Japanese Cosmetic Ingredients Codex, The Pharmacopoeia of Japan, and The Japan'"'"'s Specifications and Standards for Food Additives.

4. The method for the production of resin particles according to claim 1, wherein the liquid material is a dihydric or trihydric alcohol.

5. The method for the production of resin particles according to any one of claims 1 to 4, wherein the resin particles comprise a thermoplastic resin.

6. The method for the production of resin particles according to claim 5, wherein the thermoplastic resin is a polyamide resin.

7. The method for the production of resin particles according to claim 1, wherein the method is carried out to yield resin particles for use in cosmetics.

8. The method for the production of resin particles according to claim 1, wherein the aqueous dispersion contains 100 parts by weight of the resin particles, “

A”

parts by weight of water and “

B”

parts by weight of the liquid material, wherein the wet cake obtained as a result of filtration of the aqueous dispersion contains “

C”

percent by weight of water, and wherein the parameters “

A”

, “

B”

, and “

C”

satisfy the following condition;

(100×

B×

C)/[(100−

C)×

(A+B)]=0.01 to 20.