Ex parte Lin et al.

Board of Patent Appeals and Interferences

Feb 16, 2001

08383238 (B.P.A.I. Feb. 16, 2001)

1
The opinion in support of the decision being entered today was
not written for publication and is not binding precedent of
the Board.
Paper No. 18
UNITED STATES PATENT AND TRADEMARK OFFICE
__________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________
Ex parte SHIOW-CHING LIN, STEVEN J. BURKS,
BRADLEY L. KENT and CRAIG N. KAMSLER
__________
Appeal No. 1997-4104
Application 08/383,238
___________
ON BRIEF
___________
Before JOHN D. SMITH, WARREN, and TIMM, Administrative Patent
Judges.
JOHN D. SMITH, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal pursuant to 35 U.S.C. § 134 from the
final rejection of claims 1 through 21.
Representative claims 1 and 12 are reproduced below:
1. A paint composition comprising:
(a) from about 30 wt.% to about 70 wt.%, based upon the
weight of said paint composition, of a binder component,
wherein said binder component comprises at least about 35
Appeal No. 1997-4104
Application 08/383,238
2
wt.%, based on the total weight of said binder component, of a
polyvinylidene fluoride polymer having a melt viscosity of at
least 40 kPoise, and from 0 wt.% to about 65 wt.%, based on
the total weight of the binder component, of a polymer
compatible with polyvinylidene fluoride;
(b) from about 30 wt.% to about 70 wt.%, based on the
weight of said paint composition, of a solvent component; and
(c) a pigment, wherein said pigment is present in said
composition at a pigment-to-binder weight ratio of from 0 to
about 0.8.
12. A coated substrate, said substrate including at
least one surface, wherein at least one surface of said
substrate is coated with a paint including at least 35 wt.% of
a polyvinylidene fluoride polymer having a melt viscosity of
at least 40 kPoise.
The sole reference now relied upon by the examiner is:
Bacque et al. (Bacque) 5,095,081 Mar. 10,
1992
The appealed claims stand rejected 35 U.S.C. § 103 as
unpatentable over Bacque.
We do not sustain the stated rejection.
The subject matter on appeal is directed to a paint
composition comprising, inter alia, a binder component of a
polyvinylidene fluoride (PVDF) polymer having a melt viscosity
of at least 40 kPoise. Appellants’ composition finds
particular utility as an exterior use low gloss paint. Low
Appeal No. 1997-4104
Application 08/383,238
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gloss paints find particular utility as exterior paints for
airport buildings such as airport terminals, airplane hangars,
airport gates, and air freight buildings; bus terminals;
railroad stations and terminals; railroad crossing signals;
railroad block signals; railroad switches; bridges;
residential and industrial roofing; street light and traffic
light support structures. See the specification at page 6,
second full paragraph.
Appellants explain in their specification at page 1 that
present prior art commercial polyvinylidene fluoride-
containing paints provide coatings with a 60E gloss of 30
(ASTM Designation D523-89) using a standard pigmented base
formula, such as a blue base formula, after coating
development. Appellants further acknowledge that a PVDF paint
or coating which includes a flatting agent such as fumed
silica is currently available which effects a reduced gloss,
but disavantageously provides reduced weatherability
properties. Apparently, in further referring to such prior
art PVDF resins, appellants report that such resins “for use
in maintenance-free paints” have a melt viscosity of from
Appeal No. 1997-4104
Application 08/383,238
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about 29 kPoise to about 33 kPoise. See the specification at
page 2, third full paragraph. Appellants’ invention is said
to be based on the finding that when one polymerizes
vinylidene fluoride such that the resulting PVDF polymer has a
melt viscosity of at least 40 kPoise, and formulates a paint
including
such polymer, “such paint has a reduced gloss while being easy
to apply and retaining weatherability.” Again, see the third
full paragraph of page 2 of the specification.
As shown in figure 1 of the application, appellants
demonstrate that the gloss of a PVDF coating decreases quickly
with increasing melt viscosity when the melt viscosity is
below 35 kPoise. The gloss reduction rate decreases when the
melt viscosity exceeds 35 kPoise. As reported in the
specification at the bottom of page 9, if low gloss at 60E is
defined arbitrarily to be 15 or lower, the melt viscosity of
the PVDF resin should be at least 48 kPoise. To obtain a PVDF
paint having a gloss of 10 or lower, the resin should have a
Appeal No. 1997-4104
Application 08/383,238
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melt viscosity of at least 54 kPoise. Thus, by defining their
PVDF polymer component as having a melt viscosity of at least
40 kPoise, appellants have inherently defined the composition
as a low gloss paint.
In finding the herein claimed invention obvious over the
teachings of Bacque, the examiner states in his answer at
pages 4 and 5 that this prior art reference relates to a
process for manufacturing vinylidene fluoride polymers and to
the use of these polymers in paints. A typical paint
formulation disclosed in the prior art Bacque reference at
column 4, lines 1-10 is comprised of a PVDF polymer, an
acrylic resin, a pigment, a solvent and an anionic surfactant.
The examiner further asserts that the disclosed amounts of
resin, pigment and solvents encompass those that are instantly
claimed and the examiner contends that it would have been
obvious to one of ordinary skill in this art to simply follow
the teachings of Bacque to arrive at the claimed invention.
The examiner further points out that since the claims on
appeal do not expressly specify a gloss value, it is
immaterial that Bacque’s primary purpose is to produce a paint
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Application 08/383,238
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having a high gloss.
With respect to the key limitation in appellants’ claims
requiring the specified high melt viscosity for the PVDF
polymer component of appellants’ paints, the examiner states
that appellants have not established the criticality of that
limitation regarding melt viscosity. The examiner further
states that he assumes that the composition of Bacque
satisfies the limitation of melt viscosity because it has not
been disproved by appellants. Further, the examiner’s
assumption above is apparently based on his “feeling” that
example 4 (a control example of Bacque which appears at column
4, line 58), possesses a melt viscosity corresponding to the
claimed melt viscosity because this example is said to provide
a low-gloss paint. This example, however, reports a 60E gloss
value of 48, a value substantially higher than the low-gloss
values produced by appellants’ paints which have been
arbitrarily defined to be 15 or lower. Based on appellants’
Figure 1 graph, the example 4 paint of Bacque having a gloss
value at 60E of 48 would appear to have a melt viscosity of
less then 30 kPoise. In short, this example would appear to
Appeal No. 1997-4104
Application 08/383,238
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be representative of what appellants have referred to as prior
art or current PVDF resins used in maintenance-free paints
which have a melt viscosity from about 29 kPoise to about 33
kPoise. Again, see the specification at page 2, third full
paragraph.
With respect to the examiner’s contention that the manner
in which Bacque’s example 4 PVDF polymer is made is similar to
the way appellants’ PVDF polymer is made, we note the
following. Based on the disclosures in Bacque at column 1,
line 23 through line 60, it is apparent that Bacque’s example
4 is made by a prior art process of polymerizing vinylidene
fluoride monomer in an aqueous medium in the absence of an
emulsifying agent, and with the use of peroxydisulphates as
initiators, and in the absence of chain control agents. On
the other hand, as evident from appellants’ specification at
pages 4 and 5, appellants form the herein claimed
polyvinylidene fluoride polymers by an emulsion polymerization
process which employs a fluorosurfactant, i.e., an emulsifier,
with an initiator such as di-t-butyl peroxide. Accordingly,
there are substantial differences between the way appellants
Appeal No. 1997-4104
Application 08/383,238
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form their desired high melt viscosity PVDF resin component
and the manner in which the example 4 PVDF resin component of
the prior art is formed.
Finally, the examiner argues that the prior art reference
to Bacque “seems to associate” high molecular weight “i.e.,
high melt viscosity” with low gloss with respect to a PVDF
polymer component in a paint. Accordingly, the examiner
argues that once this relationship is known, it is a matter of
optimization to one of ordinary skill in the art to obtain a
polymer having appellants’ claimed melt viscosity “coupled
with a desired gloss.” It is our view, however, that the
examiner has failed to meet his burden of demonstrating that
the low-gloss paints referred to in the Bacque reference at
column 1, lines 23 through 41, are equivalent to the low-gloss
paints described in appellants’ specification. As we have
pointed out above, example 4 of Bacque which is apparently
made by the process disclosed at column 1, lines 23 through 41
has a reported gloss at 60E of 48 percent. Again, this is a
value substantially higher than the gloss values produced by
appellants’ paints. Under the circumstances of this case, we
Appeal No. 1997-4104
Application 08/383,238
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find that the examiner has provided an inadequate factual
basis to support a reasonable belief that the claimed melt
viscosity value for appellants’ PVDF resin component in
appellants’ paints is an inherent characteristic of the prior
art paints. Compare In re Best, 562 F.2d 1252, 1555, 195 USPQ
430, 433 (CCPA 1977). Accordingly, the examiner’s stated
rejection of the appealed claims cannot be sustained.
The decision of the examiner is reversed.
REVERSED
JOHN D. SMITH )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
CHARLES F. WARREN )
Administrative Patent Judge ) APPEALS AND
)
) INTERFERENCES
)
CATHERINE TIMM )
Administrative Patent Judge )
Appeal No. 1997-4104
Application 08/383,238
10
JDS:pgg
John P. Luther
Duane, Morris & Heckscher
One Liberty Place
Philadelphia, PA 19103-7396