Method for purifying hydroxycarboxylic acid, method for...

Details Method for purifying hydroxycarboxylic acid, method for... Method for purifying hydroxycarboxylic acid, method for...

2007-07-10

2011-10-18

Oh, Taylor Victor (Department: 1622)

Synthetic resins or natural rubbers -- part of the class 520 ser

Synthetic resins

At least one aryl ring which is part of a fused or bridged...

C528S361000, C549S326000, C562S579000, C562S580000

Reexamination Certificate

active

08039548

ABSTRACT:
A process for purification of a hydroxycarboxylic acid by distillation, comprising: distilling a hydroxycarboxylic acid solution containing a high-boiling point hydroxy compound comprising at least one species selected from the group consisting of alcohols and phenols having a higher boiling point than the hydroxycarboxylic acid. As a result, a hydroxycarboxylic acid suitable as a starting material for production of a polyhydroxycarboxylic acid can be obtained. The purified hydroxycarboxylic acid is further polycondensed to provide a hydroxycarboxylic acid oligomer, which is de-polymerized to provide a cyclic ester comprising a dimer of the hydroxycarboxylic acid, and the cyclic ester is converted into a polyhydroxycarboxylic acid by ring-opening polymerization thereof.

REFERENCES:
patent: 2004/0122240 (2004-06-01), Yamane et al.
patent: 2005/0020853 (2005-01-01), Kuroda et al.
patent: 2007/0015936 (2007-01-01), Meng et al.
patent: 1 232 137 (2005-07-01), None
patent: 02/083661 (2002-10-01), None
Supplementary European Search Report issued Aug. 24, 2010 in European Patent Application No. 07 79 0569.
International Search Report issued in the International (PCT) Application of which the present application is the U.S. National Stage, Sep. 2007.

Affiliated with

Also associated with

Rating

Method for purifying hydroxycarboxylic acid, method for... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for purifying hydroxycarboxylic acid, method for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for purifying hydroxycarboxylic acid, method for... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-4266995