Ex Parte Sakurai et al

Board of Patent Appeals and Interferences

Aug 29, 2012

11033800 (B.P.A.I. Aug. 29, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________________

Ex parte MASATO SAKURAI, SHOICHI YOSHIHARA, and
MITSURU ONISHI
____________________

Appeal 2010-006072
Application 11/033,800
Technology Center 3700
____________________

Before: JENNIFER D. BAHR, CHARLES N. GREENHUT, and
MICHAEL L. HOELTER, Administrative Patent Judges.

BAHR, Administrative Patent Judge.

DECISION ON APPEAL

Appeal 2010-006072
Application 11/033,800

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STATEMENT OF THE CASE
Masato Sakurai et al. (Appellants) appeal under 35 U.S.C. § 134 from
the Examiner’s decision rejecting under 35 U.S.C. § 103(a) claims 1 and 4-8
as unpatentable over Sakurai1 and Yoder2 and rejecting claim 11 as
unpatentable over Sakurai, Yoder, and Hong3. The Examiner indicated that
claims 2, 3, 9, and 10 “are allowable over the applied references.” Ans. 2.
We have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.
The Claimed Subject Matter
Claim 1, reproduced below, is illustrative of the claimed subject
matter.
1. A method wherein the surface tension difference convection
generated at the two-fluid interface of silicone oil and
Fluorinert is utilized as the drive force of a micromachine.

OPINION
Each of Appellants’ independent claims 1, 4, 6, 8, and 11 requires the
use of surface tension difference convection generated at the two-fluid
interface of silicone oil and Fluorinert as the drive force of a micromachine
(claim 1), of a rotary drive mechanism for a micro-turbine (claim 4), of a
unidirectional drive mechanism (claim 6), in a method of stirring and mixing

1 Masato Sakurai et al., Primitive Study of a New Fluid Handling in
Microgravity Condition, 23rd INT’L SYMPOSIUM ON SPACE TECH. AND SCI., 1-
4 (2002) (referred to by the Examiner as “Masato et al”).
2 US 2006/0094108 A1, iss. May 4, 2006.
3 Seungbae Hong et al., Numerical Simulation of Mixing in a Micro-Channel
with Non-Uniform Zeta Potential Surface, 1 Micro Total Analysis Systems
2002, 94-96 (Y. Baba et al. eds. 2002) (referred to by the Examiner as
“Seungbae et al”).
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Application 11/033,800

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a plurality of fluids (claim 8), or in a method of stirring and mixing a sample
reagent on a μTAS chip (claim 11).
The Examiner found that Sakurai discloses the use of surface tension
to drive a micromachine. Ans. 3; see Sakurai Abstr. (pointing out that in the
microscale wetting and surface tension become dominant, and proposing
that “the development of a micro-reactor or a micro-machine is a promising
application area”). The Examiner found that Sakurai “does not disclose the
specific fluids including silicone and Fluorinert.” Ans. 3-4.
The Examiner found that “Yoder teaches it’s well known to use
surface tension between two fluids to cause movement in a microfluidic
system (note page 2, lines 17-19); on page 7, paragraph 89, Yoder teaches
that the fluids can be silicon oil, Fluorinert or in combination of the fluids.”
Ans. 4. Relying on those findings, the Examiner determined that it would
have been obvious to “select different types of fluids such as silicone and
Fluorinert in the micro-machine of [Sakurai] as taught by Yoder … for the
purpose of generating appropriate force depending on the characteristics of
the fluids.” Id.
We agree with Appellants that the portions of Yoder cited by the
Examiner do not support the Examiner’s finding that Yoder teaches
generating surface tension between silicon[e] and Fluorinert for generating a
driving force. See App. Br. 12; Reply Br. 5 (urging that “Yoder refers to the
surface tension of a fluid, i.e., the liquid sample, for drawing the liquid into
and loading (by capillary action) through-holes 12. Yoder does not disclose
using surface tension difference convection generated at a two-fluid
interface”). As explained by Appellants,
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Yoder does not teach using silicone oil and Fluorinert for
generating a force. Yoder discloses that silicon oil and
Fluorinert are immersion fluids for encapsulating a sample.
(Paragraph 89.) There is nothing in the prior art to suggest
using an immersion fluid in a microreactor or micromachine.
Thus, there is no reason one of ordinary skill in the art would
have used silicon[e] oil and Fluorinert in a micromachine or
microreactor as taught in Sakurai.
Reply Br. 7.
Yoder addresses the hydrophilic interface between the immersion
fluid and the interior walls 13 of the through-holes 12 to “enhance the
drawing power” and teaches that “[c]apillary action or surface tension of the
liquid samples may be used to load the sample through-holes 12” of the
sample array 10. Paras. [0010] and [0011]. Yoder also teaches that it is
often useful to place an encapsulation in the interior volume 24 with the
microfluidic sample array. Para. [0089]. Yoder uses the term
“encapsulation fluid” interchangeably with “immersion fluid” to reflect that
the encapsulation fluid may advantageously, but does not necessarily, assist
in isolating the through-holes of the microfluidic sample array from one
another; primarily, the encapsulation fluid helps prevent evaporation of
samples and maintains a uniform temperature throughout the array. Id. The
immersion fluid is distinct from the liquid samples, which are loaded into the
sample through-holes of the array. Yoder teaches that typical
immersion/encapsulation fluids may include silicon oil and Fluorinert, alone
or in combination with one another. Id. However, Yoder does not disclose
generating surface tension, much less surface tension difference convention,
at the two-fluid interface of any of the components of the immersion fluid.
Accordingly, the Examiner’s articulated reason for modifying Sakurai
by providing silicone and Fluorinert in Sakurai’s micro-machine for the
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purpose of generating appropriate force is premised on an incorrect finding
(i.e., that Yoder teaches using surface tension between two fluids, such as
silicon oil and Fluorinert, to cause movement in a microfluidic system), and
thus lacks rational underpinnings. Thus, we do not sustain the rejection of
claims 1 and 4-8 as unpatentable over Sakurai and Yoder.
In rejecting claim 11 as unpatentable over Sakurai, Yoder, and Hong,
the Examiner does not articulate any findings or reasoning that overcomes
the deficiency in the combination of Sakurai and Yoder discussed above.
Thus, we also do not sustain the rejection of claim 11.
DECISION
The Examiner’s decision rejecting claims 1, 4-8, and 11 is reversed.
REVERSED

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