Appeal No. 2003-0849
Application 09/622,916
acrylic or methacrylic acid from a liquid. The claimed subject matter requires the
rectificative isolation to be carried out with the addition of a surfactant.
According to the Examiner, Herbst teaches a process for the rectificative
isolation of acrylic or methacrylic acid from an organic liquid. The Examiner
acknowledges that Herbst does not disclose the use of a surfactant in the
rectificative process. The Examiner asserts that Egly discloses the use of a
polymerization inhibitor, phenothiazine, and Frank discloses the use of surfactants
in the recovery and purification of methacrylic acid. Specifically the Examiner
states:
Herbst et al teaches a process for the separation, by rectification, of
(meth)acrylic acid from a mixture containing (meth)acrylic acid and an
inert hydrophobic organic liquid with a higher boiling point than
(meth)acrylic acid in the presence of a primary amine (see claim 1 on
page 20 of the English translation of Herbst et al). Herbst et al does
not teach the use of surfactant to reduce the formation of polymers
during the rectification process. Although Egly et al teaches the use of
phenothiazine (i.e., an amine) as the polymerization inhibitor (Col.
4:56-59) it is Frank et al who teaches that in the recovery and
purification of methacrylic acid the problem of plugging is avoided by
the use of surfactants (see Frank’s abstract). Frank et al further
teaches that the surfactant prevents methacrylic acid from adhering to
the pipe walls and forming polymerization sites (Col. 2:37-40).
Therefore, the instantly claimed process would have been obvious to
one of ordinary skill in the art at the time the invention was made. In
order to prevent formation of polymer of (meth)acrylic acid on the
wall of the apparatus used in the process for isolation of (meth)arylic
acid (i.e., the process of Herbst et al), the addition of a surfactant, as
taught by Frank et al, provides the requisite motivation.
Answer, pages 5-6.
-4-
Page: Previous 1 2 3 4 5 6 7 8 9 Next
Last modified: November 3, 2007