Appeal No. 1999-1008
Application 08/713,905
We have carefully compared the specific disclosure appellants rely on with other relevant
parts of the written description. We find that appellants disclose in the written description of
their specification that a mixture of the three isomeric ether isocyanates as claimed is “new”
(page 7), and exemplify a vapor phase phosgenation process in specification Example 1 which
produces such a mixture having “a content of hydrolyzable chlorine of 43 ppm” (page 8). The
subject limitation was added by amendment to original claim 3 to obtain appealed claim 3.
Appellants further state that
[c]ertain ether isocyanates can be obtained in yields of up to about 80% by simple base
phosgenation. (See, for example, DE-A 1,154,092.) However, the products of such
processes have very high residual chlorine contents (0.1%). Such a high chlorine
content in the diisocyanate frequently makes it difficult to use those products. For
example, such chlorine-containing diisocyanates are not useful for the preparation of
non-discoloring raw materials for coatings. . . . [Id., page 1, line 26, to page 2, line 1;
part relied on by appellants emphasized.]
Although not relied on in the brief or reply brief, appellants further state that
DE-A 1,793,329 discloses a cold phase-hot phase phosgenation in solution for the
preparation of ether(poly)isocyanates. It is alleged that very little, if any, splitting of
the ether occurs. However, the yields of isocyanate are only 60 top 75% of the
theoretical yield. The chlorine content of the products, at 400 to 2000 ppm, is far too
high for many applications, particularly for paint and coating applications.
[Specification, page 3, lines 6-11; emphasis supplied.]
Appellants state as an object of the invention that “the production of high quality
isocyanates containing ether groups” and that such object is “accomplished by converting mono-
and polyamines containing ether groups to the corresponding isocyanates in very good yields and
in high purity, without splitting the ether group” (id., page 3, lines 17-18 and 22-25; emphasis
supplied).
Although not relied on in the brief or reply brief, appellants further state that “[t]he ether
isocyanates prepared by the process of the present invention are valuable raw materials for the
production of . . . coating materials . . . .” (specification, page 7, lines 11-13).
In each of specification Examples 2 through 5, a different single ether mono- or di-
isocyanate compound, none encompassed by appealed claim 3, is produced by the process of
specification Example 1, wherein the hydrolyzable chlorine content of the products ranges from
24 ppm to 48 ppm. In specification Comparative Example (page 10), “the mixture of diamines
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