Title:
METHOD FOR PRODUCING POLYVINYL ALCOHOL RESIN
Document Type and Number:
WIPO Patent Application WO/2011/108152
Kind Code:
A1
Abstract:
Provided is a method for producing a polyvinyl alcohol resin, with which impurities can be efficiently eliminated by a small amount of washing liquid. Polyvinyl alcohol obtained via a polymerization step (step S1) and a saponification step (step S2) is washed in a washing step (step S3) using a washing liquid comprising methyl acetate: 1 to 40 parts by mass, methanol: 50 to 98.9 parts by mass, and water: 0.1 to 10 parts by mass. The solid concentration of a slurry containing the washing liquid is brought to 1 to 30 mass% in the washing step (step S3).
Inventors:
WATANABE SATOSHI (JP)
KOZUKA TAKAHIRO (JP)
KOZUKA TAKAHIRO (JP)
Application Number:
PCT/JP2010/070173
Publication Date:
September 09, 2011
Filing Date:
November 12, 2010
Export Citation:
Assignee:
DENKI KAGAKU KOGYO KK (JP)
WATANABE SATOSHI (JP)
KOZUKA TAKAHIRO (JP)
WATANABE SATOSHI (JP)
KOZUKA TAKAHIRO (JP)
International Classes:
C08J3/12; C08F8/12; C08F16/06
Foreign References:
| JP2001081128A | 2001-03-27 | |||
| JP2007245432A | 2007-09-27 | |||
| JPH09504571A | 1997-05-06 | |||
| JPH08511053A | 1996-11-19 | |||
| JP2002301715A | 2002-10-15 | |||
| JP2002060495A | 2002-02-26 | |||
| JP2007245432A | 2007-09-27 |
Other References:
See also references of EP 2543692A4
Attorney, Agent or Firm:
WATANABE KAORU (JP)
Kaoru Watanabe (JP)
Kaoru Watanabe (JP)
Download PDF:
Claims: