Robert L. Ballard et al.

Patent Trials and Appeals Board

Jan 2, 2020

13749823 - (D) (P.T.A.B. Jan. 2, 2020)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
13/749,823 01/25/2013 Robert L. Ballard Z013 1100US.1 7013
26158 7590 01/02/2020
WOMBLE BOND DICKINSON (US) LLP
ATTN: IP DOCKETING
P.O. BOX 7037
ATLANTA, GA 30357-0037
EXAMINER
NORRIS, CLAIRE A
ART UNIT PAPER NUMBER
1778
NOTIFICATION DATE DELIVERY MODE
01/02/2020 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
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PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte ROBERT L. BALLARD, BRUCE L. ANNEAUX,
JOSHUA L. MANASCO, DAVID P. GARNER, and PING HAO
____________

Appeal 2018-009241
Application 13/749,823
Technology Center 1700
____________

Before DONNA M. PRAISS, CHRISTOPHER C. KENNEDY, and
JEFFREY R. SNAY, Administrative Patent Judges.

SNAY, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 4–14, 26–34, 56–65, 72, 73, 75, and 76.
We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.

1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R.
§ 1.42(a). Appellant identifies Zeus Industrial Products, Inc., as the real
party in interest. Appeal Br. 1.
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BACKGROUND
The invention relates to porous media, such as a filter or filtration
medium for removing particulates from a gas or liquid stream. Spec. 1:20–
22. According to the Specification, poly(tetrafluorethylene) (PTFE) offers
certain advantageous properties, but cannot be processed by conventional
molten polymer techniques. Id. at 3:5–9. The Specification describes
forming a nonwoven mat comprising electrospun PTFE fibers, which mat
can be useful as a filtration medium. Id. at 4:2–5. Independent claims 4 and
65 read:
4. A filtration medium comprising:
a mat comprising nonwoven, electrospun
poly(tetrafluoroethylene) (PTFE) fibers in an arrangement
within the mat, wherein the electrospun PTFE comprised in the
mat is sintered in such a manner that removes substantially all
of a fiberizing polymer, wherein the arrangement of nonwoven,
electrospun PTFE fibers within the mat is such that the mat
meets HEPA standard IEST-RP-CC001.3, wherein the fibers of
the mat comprise nonwoven, electrospun PTFE fibers having an
average fiber diameter between about 250 nm and about 1500
nm, and wherein an average thickness of the mat is about 200
µm or less.

65. A nonwoven fabric comprising:
a nonwoven mat comprising electrospun
poly(tetrafluoroethylene) PTFE fibers arranged within the mat,
wherein the electrospun PTFE comprised in the mat is sintered
in such a manner that removes substantially all of a fiberizing
polymer, wherein the arrangement of fibers within the mat is
such that the nonwoven mat both
passes the blood penetration test of ASTM F1670,
and
provides air permeability of at least about 2.5 cfm.
Appeal Br. 27, 32 (Claims Appendix).
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Independent claim 26 recites essentially the same filtration medium as
in claim 4, except that the recited mat meets a ULPA filter standard.
Independent claim 56 essentially combines the filtration media of claims 4
and 26. Each remaining claim on appeal depends from claim 4, 26, or 56.

REJECTIONS
I. Claims 4–14, 26–34, 56–64, 72, 73, 75, and 76 stand rejected under
35 U.S.C. § 103(a) as unpatentable over Walls2 and Xiong.3
II. Claim 65 stands rejected under 35 U.S.C. § 103 as unpatentable over
Martin4 and Wadsworth.5
OPINION
Rejection I: obviousness over Walls and Xiong
With regard to the Examiner’s rejection over Walls and Xiong,
Appellant argues the rejected claims as a group, with separate additional
arguments directed to each of independent claims 4, 25, and 56. See Appeal
Br. 6–21. Appellant does not separately argue any dependent claim. We
address Appellant’s arguments in connection with independent claims 4, 26,
and 56 below. Each of claims 5–14, 27–34, 57–64, 72, 73, 75, and 76 stands
or falls with the independent claim from which it depends.
Claim 4
With regard to claim 4 and relevant to Appellant’s arguments on
appeal, the Examiner finds that Walls discloses a filtration mat formed from

2 US 2011/0174158 A1, published July 21, 2011 (“Walls”).
3 CN 101530750 A, published September 16, 2009, as translated (“Xiong”).
4 US 4,043,331, issued August 23, 1977 (“Martin”).
5 US 2005/0079379 A1, published April 14, 2005 (“Wadsworth”).
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electrospun polymer fibers that meets all of the recited dimensions and
characteristics, except Walls does not specify that the electrospun fibers are
PTFE. Final Act. 4. The Examiner finds Xiong teaches that electrospun
PTFE fibers exhibit chemical stability and wide operating temperatures in
sintered nonwoven filtration mats and, therefore, would have provided a
reason to use PTFE for the electrospun fibers in Walls’ filtration mat. Id.
Appellant argues there would have been no reason to combine the
teachings of Walls and Xiong because Walls’ electrospinning process is
solution-based whereas that of Xiong is dispersion-based. Appeal Br. 8.
Appellant contends that one of ordinary skill would have had “no motivation
to turn from the Walls reference to the Xiong reference, and to incorporate
materials from the Xiong reference, which are prepared via a fundamentally
different type of electrospinning.” Id. We disagree. Both Walls and Xiong
disclose electrospinning fibers from a polymer-containing source. Walls
¶ 62 (“A polymer solution . . . from reservoir 3 flows to electrospinning
emitter/orifice 2.”); Xiong 2 (“charging the spinning solution into a liquid
storage device, which was then transported to a spinning nozzle”).
Appellant presents no evidence or technical reasoning to support the
contention that the electrospinning process would have been materially
affected by whether the polymer source included a solution or a dispersion.
To the contrary, Appellant, in the Specification, essentially equates these
two sources for electrospinning fibers. Spec. 11:12–14 (“Electrospun mats
can be prepared by drawing material by electrical charge from a dispersion
(e.g., solution or suspension/dispersion.”).
Appellant also argues that Xiong uses water as a solvent in the PTFE
polymer source, and water solvent would have precluded Walls’ desired
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charge retention on the filtration mat. Appeal Br. 10. Here too, Appellant
presents no evidence to support the contention. See id. (“Water, as
employed in the methods of the Xiong reference for electrospinning
polytetrafluoroethylene, would be understood to disperse the charge.”)
(emphasis added). Moreover, the Examiner finds that Walls discloses an
alternative in which any desired charge may be applied to the filtration mat
after the electrospinning process, such that any inhibitory effect of water
solvent during electrospinning would have been rendered moot. Ans. 24
(citing Walls ¶ 140). Appellant does not persuasively dispute this finding in
the Reply Brief.
Appellant argues that Walls requires a level of control of relative
humidity in the electrospinning chamber that would be impossible in the
presence of a polymer solution/dispersion that includes water solvent.
Appeal Br. 13 (citing Walls ¶¶ 76, 77). Appellant additionally argues there
would have been no reason to expect that a mat comprising electrospun
PTFE fibers could perform the filtration function desired by Walls. Id. at
14. Appellant also argues that Xiong fails to teach sintering in a manner that
removes substantially all of a fiberizing polymer. Id. at 15. These
arguments are not persuasive of reversible error. Walls discusses humidity
control in “one embodiment” as a way to achieve fibers with fewer surface
defects rather than as a requirement for electrospinning PTFE fibers. Walls
¶ 76. Moreover, even if electrospinning PTFE fibers somehow inhibited
humidity control as Appellant suggests, a tradeoff of one advantage
(reduction of surface defects) for another (e.g. chemical stability of PTFE) is
not persuasive of reversible error in the Examiner’s obviousness
determination. See Medichem, S.A. v. Rolabo, S.L., 437 F.3d 1157, 1165
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(Fed. Cir. 2006) (“[A] given course of action often has simultaneous
advantages and disadvantages, and this does not necessarily obviate
motivation to combine.”). Regarding a reasonable expectation of success to
achieve a desired filtration capability, both Walls and Xiong disclose
nonwoven electrospun fiber mats for the express purpose of filtration.
Regarding removal of fiberizing polymer, Xiong expressly teaches
“sintering the composite superfine fiber porous membrane in a conventional
sintering apparatus to remove the matrix polymer.” Xiong 2.
Lastly, Appellant argues unexpected results, but fails to present or
point to any supporting data or evidence. Appeal Br. 20. “It is well settled
that unexpected results must be established by factual evidence. Mere
argument or conclusory statements in the specification does not suffice.” In
re De Blauwe, 736 F.2d 699, 705 (Fed. Cir. 1984) (citing In re Lindner, 457
F.2d 506, 508 (CCPA 1972)).
Claims 26 and 56
With regard to each of claims 26 and 56, Appellant relies on the same
arguments presented for claim 4. See Appeal Br. 6–15. These arguments
are not persuasive for the reasons given above.
Appellant additionally argues that neither Walls nor Xiong discloses
the ULPA filtration standard recited in claim 26. Id. at 18. However,
Appellant does not persuasively challenge the Examiner’s reasoning that
meeting known ULPA standards would have resulted from the obvious
adjustment of fiber diameter and packing density in Walls for the disclosed
objective of removing the highest quantity of particles from air as possible.
See Final Act. 9 (citing Walls ¶ 11). Nor does Appellant point to any
structural difference between the nonwoven mat recited in claim 26 and that
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which would have resulted from the combined teachings of Walls and Xiong
that could account for any meaningful difference in ability to meet a given
ULPA standard.
With regard to claim 56, Appellant argues, without elaboration
beyond pointing to arguments presented in connection with claims 4 and 26,
that neither Walls nor Xiong discloses the recited combination of HEPA and
ULPA standard compliance. Appeal Br. 19. That argument is not
persuasive for the reasons given above in connection with claims 4 and 26.
See In re Merck & Co., 800 F.2d 1091, 1097 (Fed. Cir. 1986) (“Non-
obviousness cannot be established by attacking references individually
where the rejection is based upon the teachings of a combination of
references.”) (citing In re Keller, 642 F.2d 413, 425 (CCPA 1981) (“[T]he
test [for obviousness] is what the combined teachings of the references
would have suggested to those of ordinary skill in the art.”)).
For the foregoing reasons, Appellant does not persuade us of
reversible error in the Examiner’s rejection of claims 4–14, 26–34, 56–64,
72, 73, 75, and 76 over Walls and Xiong. Rejection I is sustained.

Rejection II: obviousness over Martin and Wadsworth
With regard to claim 65 and relevant to Appellant’s arguments on
appeal, the Examiner finds that Martin discloses a nonwoven fabric of
electrospun PTFE fibers, arranged in a mat such that blood and other body
fluids are excluded and oxygen is allowed to pass. Final Act. 20–21. The
Examiner reasons that it would have been obvious to adjust pore size and
thickness of Martin’s fabric to assure compliance with the blood penetration
test of ASTM F1670, and to maximize air permeability, consistent with
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Martin’s objective of precluding blood and other body fluids while allowing
passage of oxygen. Id. at 21.
Appellant argues neither reference teaches the recited specific value
of 2.5 cfm, and “there is no teaching or suggestion in the cited art that a
material meeting both limitations of pending claim 65 can be provided
according to the teachings of the Martin and Wadsworth references.”
Appeal Br. 23. Appellant’s arguments do not persuasively refute the
rationale set forth by the Examiner. The Examiner identifies a technical
basis in Martin for a reason to maximize air permeability, sufficient to
support a prima facie determination that it would have been obvious to
provide air flow of 2.5 cfm or greater. The Examiner also identifies a
technical basis in the combined teachings of Martin and Wadsworth to
provide compliance with a known ASTM blood penetration test. An express
suggestion or motivation in the prior art is not a requirement for an
obviousness determination. See KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398,
421 (2007) (“A person of ordinary skill is also a person of ordinary
creativity, not an automaton.”).
Rejection II also is sustained.
CONCLUSION
The Examiner’s decision rejecting claims 4–14, 26–34, 56–64, 72, 73,
75, and 76 is affirmed.

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DECISION SUMMARY
In summary:
Claim(s)
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
4–14, 26–
34, 56–64,
72, 73, 75,
76
103(a) Walls, Xiong 4–14, 26–
34, 56–64,
72, 73, 75,
76

65 103(a) Martin, Wadsworth 65
Overall
Outcome
4–14, 26–
34, 56–65,
72, 73, 75,
76

No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv).
AFFIRMED