Ex Parte Yuan

Board of Patent Appeals and Interferences

Oct 27, 2009

11141685 (B.P.A.I. Oct. 27, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
_________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte SHI YUAN
__________

Appeal 2009-008234
Application 11/141,685
Technology Center 1700
___________

Decided: October 27, 2009
___________

Before EDWARD C. KIMLIN, ADRIENE LEPIANE HANLON, and
MARK NAGUMO, Administrative Patent Judges.

HANLON, Administrative Patent Judge.

DECISION ON APPEAL

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A. STATEMENT OF THE CASE
This is an appeal under 35 U.S.C. § 134 from an Examiner’s decision
rejecting claims 1-10 and 12-18. We have jurisdiction under 35 U.S.C.
§ 6(b). We AFFIRM.
Claim 1, reproduced below, is illustrative of the subject matter on
appeal.
1. A method for making powder selected from metal
powder or metal oxide powder or both comprising heat treating
said powder in a flowable state by microwave energy to form a
heat-treated powder, and further reducing said heat-treated
powder to a flowable powder.

App. Br., Claims Appendix.1
The following Examiner’s rejections are before us on appeal:2
(1) Claims 1, 2, 6-10, and 12-18 are rejected under 35 U.S.C.
§ 103(a) as unpatentable over Oda3 in view of McMillan.4
(2) Claims 3-5 are rejected under 35 U.S.C. § 103(a) as
unpatentable over Oda in view of McMillan and Fife.5
B. ISSUES
(1) Has the Appellant identified reversible error in the Examiner’s
conclusion that using a microwave to heat treat flowable powder as recited

1 Appeal Brief dated July 29, 2008.
2 In the Examiner’s Answer, the Examiner withdrew the §103(a) rejections
based on McMillan in view of Oda and McMillan in view of Oda and Fife
and entered the following rejections as new grounds of rejection.
Examiner’s Answer dated September 15, 2008 (“Ans.”), at 2-3.
3 US 2002/0152842 A1 to Oda published October 24, 2002.
4 US 5,772,701 to McMillan issued June 30, 1998.
5 US 6,322,912 B1 to Fife issued November 27, 2001.
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in claim 1 would have been obvious to one of ordinary skill in the art in
view of the combined teachings of Oda and McMillan?
(2) Has the Appellant identified reversible error in the Examiner’s
conclusion that the pre-agglomeration step recited in claim 9 would have
been obvious to one of ordinary skill in the art in view of the teachings of
Oda?
(3) Has the Appellant identified reversible error in the Examiner’s
finding that an oxide layer is formed on the heat-treated powder of
McMillan as recited in claim 18?
(4) Has the Appellant identified reversible error in the Examiner’s
conclusion that it would have been obvious to one of ordinary skill in the art
to employ a metal oxide powder in the method of Oda as recited in claim 3
based on the combined teachings of the prior art of record?
C. FINDINGS OF FACT
1. Appellant’s Specification
The Appellant’s invention relates to metal powder and metal oxide
powders used for capacitor anodes and further relates to methods for heat
treating the metal powder and metal oxide powders. Spec., para. [0001].
According to the disclosed method, metal powder or metal oxide
powder is heat-treated by microwave energy. The powder is generally a
flowable powder and not a compressed or sintered body of powder. The
powder can be in a pre-agglomerated form or an un-agglomerated form. The
pre-agglomerated powder can be agglomerated in any fashion, such as by a
dry agglomeration or wet agglomeration, and the particles can have any
agglomerate size, such as from about 30 to 300 µm. Spec., para. [0034].
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Upon heat treatment by microwave energy, the heat-treated powder is
crushable and/or millable (or otherwise reducible to powder form) to the
point where it can be agglomerated powder. Spec., para. [0036].
According to the Appellant, the order of steps typically used in
tantalum anode formation is:
Basic lot tantalum powder from sodium reduction → optional
pre-agglomeration → heat treatment to achieve heat-
agglomerated powder → milling and crushing to form
agglomerated particles → deoxidation step → compressing to
form a pressed body → sintering to form a sintered body.

App. Br. 18; see also Spec., paras. [0009], [0036]-[0039].
2. Oda
The invention disclosed in Oda relates to nitrogen-containing metallic
powder which is employed in an anode electrode of a solid electrolytic
capacitor. Oda, para. [0002].
The nitrogen-containing metallic powder is powder of niobium or
tantalum. Oda, para. [0028].
No particular limitation is imposed on the type of niobium compound
or tantalum compound which may be employed. Examples of niobium
compounds include oxides such as niobium pentoxide. Oda, para. [0032].
Oda discloses that the metallic powder is subjected to pre-treatment,
such as thermal agglomeration, deoxidation, passivation, and stabilization,
and subsequently shaped and sintered. Oda, para. [0048].
According to Oda, the thermal agglomeration treatment is carried out
by heating the metallic powder under a vacuum for agglomeration. Oda,
para. [0049].
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Oda discloses that the powder is heated at 800ºC. to 1,400ºC. under a
vacuum for 0.5 to 2 hours. Oda, para. [0050].
Subsequently, cake-like powder obtained through thermal
agglomeration is milled in air or inert gas, and a reducing agent is added to
the particles. Oda, para. [0051].
Oda discloses that before thermal agglomeration, pre-agglomeration
by a wet agglomeration treatment is preferably carried out. Oda, para.
[0050].
3. McMillan
McMillan discloses a method of making tantalum anodes for tantalum
capacitors. According to the method, tantalum compacts, along with loose
tantalum powder, are placed in a microwave-transparent casket and heated
with microwave energy to effect at least partial sintering of the compacts.
McMillan 1:5-12.
McMillan discloses that microwave methods could result in reduced
total power consumption, i.e., lower power and shorter residence times, and
thus result in a manufacturing cost savings compared to conventional
vacuum sintering methods. McMillan 2:30-35.
In one example, samples were heated in a microwave while
maintaining a vacuum of 10-6 Torr and a sintering temperature of 1500ºC. to
1600ºC. McMillan 3:10-15.
4. Fife
The invention disclosed in Fife relates to oxygen reduced valve metal
oxides which have beneficial properties, especially when formed into an
electrolytic capacitor anode. Fife 1:28-31.
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Fife discloses that the starting valve metal oxide is most preferably a
niobium oxide, a tantalum oxide, or alloys thereof. Fife 2:6-14.
D. PRINCIPLES OF LAW
A claimed invention is not patentable if the subject matter of the
invention would have been obvious to a person having ordinary skill in the
art at the time the invention was made. 35 U.S.C. § 103(a); KSR Int’l Co. v.
Teleflex Inc., 550 U.S. 398, 406 (2007); Graham v. John Deere Co.,
383 U.S. 1, 13 (1966).
Facts relevant to a determination of obviousness include (1) the scope
and content of the prior art, (2) any differences between the claimed
invention and the prior art, (3) the level of skill in the art, and (4) any
relevant objective evidence of obviousness or non-obviousness. KSR,
550 U.S. at 406; Graham, 383 U.S. at 17-18.
The test for obviousness “is what the combined teachings of the
references would have suggested to those of ordinary skill in the art.” The
test is not that the claimed invention must be expressly suggested in any one
or all of the references. In re Keller, 642 F.2d 413, 425 (CCPA 1981).
“[A]ll disclosures of the prior art, including unpreferred embodiments,
must be considered.” In re Lamberti, 545 F.2d 747, 750 (CCPA 1976).
“Obviousness does not require absolute predictability of success.” In
re O’Farrell, 853 F.2d 894, 903-904 (Fed. Cir. 1988). “For obviousness
under § 103, all that is required is a reasonable expectation of success.” Id.
at 904.

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E. ANALYSIS
1. Issue (1)
The Examiner found that Oda discloses the step of heat treating a
metal powder in a flowable state but does not specify that the powder is heat
treated using microwave energy. Nonetheless, the Examiner found that
McMillan discloses heat treating loose powders using microwave energy.
The Examiner concluded that it would have been obvious to one of ordinary
skill in the art to heat treat the powder of Oda using microwave energy as
disclosed by McMillan in order to heat the powder effectively. Ans. 4.
The Appellant argues that Oda does not expressly disclose that the
powder is, or optionally can be, in a flowable state for the thermal
agglomeration treatment. Reply Br. 9.6
The Appellant broadly defines a “flowable” powder as a powder that
is not a compressed or sintered body of powder. Spec., para. [0034]. We
recognize that Oda does not expressly disclose that the powder is
“flowable.” However, Oda does not suggest that the powder is not
“flowable.” See, e.g., Oda, para. [0050] (referring to “nitrogen-containing
powder”).
In an attempt to establish that the powder is not in a flowable state
prior to thermal agglomeration, the Appellant argues that Oda preferably
carries out a pre-agglomeration treatment on the powder “to form lumps” of
the particles. Reply Br. 9; Oda, para. [0069]. In particular, Oda discloses:
Before thermal agglomeration, pre-agglomeration, in which
water is added to nitrogen-containing powder so as to wet all of
the powder uniformly while the powder is vibrated, is
preferably carried out.

6 Reply Brief dated October 27, 2008.
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Oda, para. [0050] (emphasis added).
The Appellant’s argument is not persuasive of reversible error for
several reasons. First, Oda suggests that the pre-agglomeration treatment is
optional. Lamberti, 545 F.2d at 750 (all disclosures of the prior art must be
considered). Second, Oda does not disclose that the powder is not flowable
after the pre-agglomeration treatment. In this regard, we note that the
Appellant subjects powder to a pre-agglomeration treatment, such as wet
agglomeration, prior to heat treatment, and the powder remains “flowable.”
See Spec., para. [0034]. Thus, on this record, there is no reason to believe
that the powder of Oda would not also remain “flowable” after the disclosed
pre-agglomeration treatment.
Next, the Appellant argues that the application of microwave energy
in McMillan is limited to sintering tantalum powder. For this reason, the
Appellant argues that “the Examiner’s proposed combination, i.e., using
microwave energy according to McMillan et al’s powder sintering procedure
as the mode of heat delivery in Oda et al.’s powder thermal agglomeration
procedure, would not yield a predictable result.” Reply Br. 11.
This argument is also not persuasive of reversible error. The
Examiner relies on McMillan to establish that microwave energy was known
in the art to be a useful heat source. McMillan also suggests that using
microwave energy can result in a reduction of total power, and thus a
reduction in cost, compared to conventional heating methods. McMillan
2:30-35. Based on these teachings, it is reasonable to find that one of
ordinary skill in the art would have considered microwave energy to be a
useful alternative to the heat source employed in Oda.
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In addition, the teachings of McMillan establish that microwave
energy was known to be capable of heating metal powders to temperatures
as high as 1600ºC. while maintaining a vacuum. McMillan 3:10-15. Thus,
we find that the teachings of McMillan also provide a reasonable expectation
of success of using microwave energy to heat treat the metal powder of Oda
under the disclosed conditions.
Finally, the Appellant argues that heat treating powder in a flowable
state by microwave energy results in improved properties. Reply Br. 6.
However, the Appellant has failed to direct us to any credible evidence
establishing that these properties would have been unexpected. See In re De
Blauwe, 736 F.2d 699, 705 (Fed. Cir. 1984) (unexpected results must be
established by factual evidence).
In sum, the Appellant has failed to identify reversible error in the
Examiner’s conclusion that the heat treating step recited in claim 1 would
have been obvious to one of ordinary skill in the art in view of the combined
teachings of Oda and McMillan.
2. Issue (2)
Claim 9 depends from claim 1 and recites that “said powder is pre-
agglomerated prior to said heat treating.” App. Br., Claims Appendix. The
Examiner found that this limitation is disclosed in Oda. Ans. 4; Oda, para.
[0050].
The Appellant argues that Oda uses the term “pre-agglomeration”
differently from the Appellant. In particular, the Appellant argues that Oda
uses the term “pre-agglomeration” to refer to macroscopic sized “lumps” (as
in paragraph [0069]) whereas the Appellant uses the same term to refer to
microscopic-sized agglomerates. Reply Br. 12-13.
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The Appellant’s argument is not persuasive of reversible error. Claim
9 does not recite the size of the pre-agglomerated particles. Moreover, the
Specification states that “[t]he particles can have any agglomerate size, such
as from about 30 to 300 µm,” and the powder “can be agglomerated in any
fashion, such as by a dry agglomeration, wet agglomeration, or the like.”
Spec., para. [0034] (emphasis added). Thus, we interpret claim 9 as
encompassing the formation of agglomerates of any size and conclude that
the reference to a size of “from about 30 to 300 µm” in the Specification is
merely exemplary. See In re Zletz, 893 F.2d 319, 321 (Fed. Cir. 1989)
(during patent examination, the pending claims must be interpreted as
broadly as their terms reasonably allow).
Oda discloses that pre-agglomeration, by a wet agglomeration, is
preferably carried out before thermal agglomeration. Oda, para. [0050].
Oda does not disclose the size of the agglomerates formed. See, e.g., Oda,
para. [0069]. Nonetheless, as discussed above, claim 9 encompasses the
formation of agglomerates of any size. Moreover, Oda and the Appellant
both contemplate using a wet agglomeration to pre-agglomerate the powder.
Thus, on this record, we conclude that the pre-agglomeration treatment
disclosed in Oda is within the scope of claim 9.
3. Issue (3)
Claim 18 depends from claim 1 and recites the additional step of
“forming an oxide layer on said heat treated powder.” App. Br., Claims
Appendix. The Examiner found that McMillan discloses this step. Ans. 4.
The Appellant’s only argument with respect to claim 18 is that there is
no teaching in McMillan that residual oxygen necessarily forms an oxide
layer on the heat-treated powder. Reply Br. 13.
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McMillan discloses that tantalum powder serves as a getter for
residual gases, such as oxygen. McMillan 2:25-27. This disclosure provides
a reasonable basis for finding that when oxygen is present as a residual gas,
tantalum powder will be oxidized and an oxide layer will be formed. In this
regard, the Examiner correctly points out that claim 18 does not limit the
coverage or thickness of the claimed oxide layer. Ans. 7.
Furthermore, Oda discloses that the metal powder may be subjected to
pre-treatment, including thermal agglomeration and passivation. Oda, para.
[0048]. We find that this disclosure in Oda reasonably suggests forming an
oxide layer on the heat-treated powder. Compare Spec., para. [0049]
(“passivation was conducted to add a layer of oxide on the Ta surface”).
4. Issue (4)7
The Examiner relies on the teachings of Fife to establish that niobium
powder and niobium oxide powders are functionally equivalent in terms of
being used as starting materials for making capacitor anodes. Ans. 5-6. The
Appellant argues that the Examiner’s reliance on Fife is misplaced. Reply
Br. 16.
Fife discloses that the starting material is most preferably a niobium
oxide, a tantalum oxide, and/or alloys thereof. Fife 2:6-14. Similarly, Oda
employs a powder of niobium or tantalum. Oda, para. [0028]. Oda
discloses that no particular limitation is imposed on the type of niobium or
tantalum compound selected and indicates that examples of niobium
compounds include oxides such as niobium pentoxide. Oda, para. [0032].

7 The Appellant indicates that claims 3-5 share the common feature of metal
oxide powder, and thus are addressed together for purposes of this appeal.
Reply Br. 15.
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Based on these teachings, it is reasonable to conclude that one of
ordinary skill in the art would have selected a metal oxide powder as a
starting material in the method of Oda.
F. DECISION
The decision of the Examiner is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).

AFFIRMED

PL Initial:
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