Title:
POLYVINYL ALCOHOL POLYMER PARTICLE
Document Type and Number:
Japanese Patent JP3618396
Kind Code:
B2
Abstract:
PURPOSE: To obtain an aqueous dispersion of a small particle size by using a polyvinyl alcohol having such a particle diameter that the particles can pass through a JIS standard sieve of a specified mesh and having an at most specified rate of elution with water.
CONSTITUTION: A polyvinyl ester such as a polyvinyl acetate is hydrolyzed to prepare PVA of a degree of polymerization of about 500-20000 and a degree of hydrolysis of about 88-100mol%. This PVA is ground by, e.g. dry grinding and classified with JIS standard sieves to separate particles in the range from about 350 mesh on to 32 mesh pass. The separated particles are treated with hot water at 110 to about 300°C to obtain PVA particles having a rate of elution with water at 40°C (as defined by the equation) of 2wt.% or below and being readily soluble in hot water.
Inventors:
Masahiro Nagao
Toshiaki Sato
Toshiaki Sato
Application Number:
JP10503495A
Publication Date:
February 09, 2005
Filing Date:
April 28, 1995
Export Citation:
Assignee:
KURARAY CO.,LTD.
International Classes:
C08L29/04; C04B24/26; C04B28/02; C08F6/00; C08F16/02; C08F16/06; C08L29/02; (IPC1-7): C04B28/02; C04B24/26; C08F6/00; C08F16/06; C08L29/04
Domestic Patent References:
| JP8245389A | ||||
| JP2147634A | ||||
| JP2227435A | ||||
| JP1158016A | ||||
| JP7002931A | ||||
| JP6206929A | ||||
| JP49027591A | ||||
| JP50010389A | ||||
| JP48011392A | ||||
| JP49064693A | ||||
| JP45040903B1 | ||||
| JP42002068B1 |
Foreign References:
| WO1994029357A1 |
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