Appeal No. 1996-0823
Application No. 08/217,189
Further, the phrase "consisting essentially of" limits the scope of a claim to the
specified ingredients or steps and those that do not materially affect the basic and
fundamental characteristics of the claimed invention. See In re Herz 537 F.2d 549, 551,
190 USPQ 461, 463 (CCPA 1976).
Applying those principles of claim interpretation to the facts before us, we conclude
that claims 1 through 4, 8 through 14, 16, and 18 preclude the steps described by Lang
where precipitation and work-up of product are carried out with acetone. See Lang,
column 9, lines 4 through 9 and column 10, lines 47 through 55. This follows because: (1)
appellants' claims recite that the work-up of N-hydroxyalkylchitosan "consists essentially of"
performing the work-up by drying and (2) the basic and fundamental characteristics of
appellants' claimed process require dispersion of chitosan in an aqueous medium
consisting essentially of water, hydroxy-
alkylation of the dispersed chitosan with epoxides, and subsequent work-up of the
N-hydroxyalkylchitosan, but without an extraction step and without precipitation and work-
up of product using a flammable organic solvent such as acetone. See the instant
specification, page 1, line 32 through page 2, line 24; page 3, line 32 through page 4, line
1; and page 5, line 33 through page 6, line 7.
Giving appellants' claims their broadest reasonable interpretation consistent with
the specification, and considering the usage "consists essentially of", we conclude that
5
Page: Previous 1 2 3 4 5 6 7 8 Next
Last modified: November 3, 2007