Appeal No. 1999-2808
Application 08/772,351
organic antioxidants include phenols (page 3, lines 51-55).
Ackerman teaches that zinc stabilizers for halogen-
containing resins, within a very short time, blacken and char
the resin to be stabilized (col. 1, lines 43-47). Ackerman
teaches that this blackening and charring can be delayed by
using zinc stearate in combination with stearates of alkali or
alkaline earth metals, but that mixtures of zinc stearate and
barium stearate, which produce by far the best results,
undesirably yellow and discolor the resin (col. 1, line 48 -
col. 2, line 9). Ackerman uses zinc soaps in combination with
potassium soaps, each soap preferably being a salt of a fatty
acid containing 6-12 carbon atoms (col. 2, lines 10-14 and 41-
48). The examiner does not rely upon any evidence that
potassium soaps were considered in the art at the time of the
appellant’s claimed invention to be suitable for use in food
contact or medical contact applications.
Rhodes teaches that “even the addition [to zinc-
containing stabilizers] of substantial amounts of alkaline
earth or alkali metal salts, such as salts of calcium, barium
or potassium, or other conventional plastics additives, such
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