Ex parte Inosaka and Muraoka

July 21, 2011 – Blog Post

Ex parte Inosaka and Muraoka (Appeal 2010-006257, Application 11/113,969)

The independent claim at issue in this case is a medical non-crosslinked pressure-sensitive adhesive composition which comprises a particular adhesive polymer A and a particular adhesive polymer B. The examiner rejected this claim as obvious over a single prior art reference.

While the Examiner recognized that the product of the reference was crosslinked due to a “relatively small amount of crosslinking agent (0.4 parts to 100 parts polymer),” the Examiner alleged that “it would have been obvious to remove the minor amount of crosslinking agent in order to arrive at a non-crosslinked adhesive composite material.” The Examiner’s only support for this allegation was the further allegation that “[i]socyanate can cause irritation and would have been an obvious deletion to one of ordinary skill in the art.”

The Board reversed the Examiner’s rejection and stated that there was no evidence or reason to suggest that omission of the crosslinking agent would have been obvious. The Board found that the Examiner had provided no evidence that isocyanates would in fact cause irritation as alleged, and that the Examiner had not provided any reason why the isocyanate, after incorporation into the completed polymer, would have been expected to cause any skin irritation.

These types of unsupported allegations by the Examiner as reasoning for modifying the prior art are not infrequent occurrences in Office Actions today. However, as the Board has decided in this case, such practice is not sufficient to support an obviousness rejection.

In addition, it is noted that the Board found that all of the examples of the reference that involve alkyl methacrylate copolymers, like that of the claimed invention, also utilize a crosslinker, and that the reference “suggests that the crosslinking treatment reduces skin irritation, rather than causes skin irritation.” These findings only further support the Board’s decision that the Examiner failed to provide evidence or reason to suggest that omission of the crosslinking agent would have been obvious. Accordingly, this decision also demonstrates that Examiners must consider references as a whole when determining potential obviousness.