Ex parte CHEH et al.

Board of Patent Appeals and Interferences

Nov 16, 1998

08186900 (B.P.A.I. Nov. 16, 1998)

Application for patent filed January 27, 1994. 1
According to appellants, this application is a continuation of
Application No. 07/990,054, filed December 14, 1992, now
abandoned.
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THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered
today (1) was not written for publication in a law
journal and (2) is not binding precedent of the Board.
Paper No. 23
UNITED STATES PATENT AND TRADEMARK OFFICE
________________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
________________
Ex parte CHRISTOPHER HUK-SHI CHEH,
SHINN-DER CHANG, CHENGWEN WENG, YUANMING TANG,
INGO B. HOLZHUETER and SAMUEL H. HAWTHORNE
________________
Appeal No. 95-5074
Application No. 08/186,9001
________________
ON BRIEF
________________
Before KIMLIN, WEIFFENBACH and ELLIS, Administrative Patent
Judges.
KIMLIN, Administrative Patent Judge.
DECISION ON APPEAL
Appeal No. 95-5074
Application No. 08/186,900
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This is an appeal from the final rejection of claims 2-9.
Claim 1, the other claim remaining in the present application,
has been allowed by the examiner. Claims 2 and 5 are
illustrative:
2. A gas chromatographic method, comprising:
loading a mixture onto a first column packed with a
stationary phase wherein mixture components of interest have
different affinities for the stationary phase, the column is
maintained at an elution temperature profile wherein the
temperature increases along the column length from the inlet
to the outlet;
flowing the mixture through the first column to effect at
least a partial separation of the mixture components;
flowing the effluent from the first column through a
second column packed with a stationary phase wherein mixture
components of interest have different affinities for the
stationary phase, the column is maintained at a temperature
profile wherein the temperature decreases along the column
length from the inlet to the outlet; and
recovering the separated components of the mixture from
the outlet of the second column.
5. A gas chromatographic method, comprising:
loading a mixture onto a column packed with a stationary
phase wherein mixture components of interest have different
affinities for the stationary phase, the column is then
provided with a variable elution temperature profile
decreasing along the column length from the inlet to the
outlet of the column;
flowing the mixture through the column to effect at least
a partial separation of the mixture components; and
Appeal No. 95-5074
Application No. 08/186,900
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recovering the separated or partially separated
components from the outlet of the column.
In the rejection of the appealed claims, the examiner
relies upon the following references:
Burow 3,225,521 Dec. 28, 1965
Cheh et al. (Cheh) 4,732,581 Mar. 22, 1988
United Kingdom (U.K. '897) 1 204 897 Sep. 9, 1970
(U.K. patent specification)
Appellants' claimed invention is directed to gas
chromatographic methods that utilize packed columns for
separating a mixture of fluid components. The method defined
by appealed claim 2 employs a first and second column wherein
the first column "is maintained at an elution temperature
profile wherein the temperature increases along the column
length from the inlet to the outlet." The gas chromatographic
method of appealed claim 5 requires a packed column that is
"provided with a variable elution temperature profile
decreasing along the column length from the inlet to the
outlet of the column."
Appealed claim 2 stands rejected under 35 U.S.C. § 102(b)
as being anticipated by Burow. Claim 5 stands rejected under
35 U.S.C. § 102(b) as being anticipated by U.K. '897. Claims
3, 4 and 6-9 stand rejected under 35 U.S.C. § 103 as follows:
Appeal No. 95-5074
Application No. 08/186,900
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(I) claims 3 and 4 over Burow in view of Cheh;
(II) claims 6 and 8 over U.K. '897 in view of Burow;
(III) claims 7 and 9 over U.K. '897 in view of Burow and
Cheh.
Upon careful consideration of the opposing arguments
presented by appellants and the examiner, we will not sustain
the examiner's rejections.
We consider first the rejection of claim 2 under § 102
over Burow. Claim 2 requires that the first column "is
maintained at an elution temperature profile wherein the
temperature increases along the column length from the inlet
to the outlet." The examiner states "[a]ny column which has
its temperature increased from its inlet end to its outlet end
has a temperature which increases along the column length from
its inlet to the outlet end because such column is initially
at ambient temperature along its length and the flow of the
gaseous component will cause such a temperature profile to
occur" (sentence bridging pages 4 and 5 of Answer).
While the examiner's statement may be true, Burow does
not describe such a column within the meaning of § 102. Burow
expressly teaches that "[a] downward temperature gradient in
Appeal No. 95-5074
Application No. 08/186,900
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the direction of flow will exist at least in column 32 by
virtue of the transfer of heat from the preheated carrier gas
to the column packing during passage therethrough, and
possibly in one or more subsequent columns" (column 6, lines
18-22, emphasis added). Burow further discloses that the
establishment of the temperature gradient in the first
separating zone is important (column 6, lines 22-24). In
addition, Burow explains that:
The temperature gradient functions to distribute the
sample over a relatively large portion of the column
by virtue of the fact that the gradual drop in
temperature encountered by the sample components as
they advance through the column slows the rate of
advance of the heavier components much more greatly
than the lighter components. [Column 6, lines 38-
44].
Based on these referenced disclosures, we cannot agree with
the examiner that Burow anticipates claim 2. While the
examiner invites attention to Burow at column 2, lines 3-39,
the disclosed reference to gradually increasing the
temperature of the separating zone, when read in context of
the entirety of Burow, is properly understood as a gradual
increase in the absolute temperature of the zone wherein a
downward temperature gradient exists in the direction of the
flow. In other words, when the variable rheostats 58, 60, 62
Appeal No. 95-5074
Application No. 08/186,900
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and 64 are switched on, both the inlet and outlet temperatures
are raised but the outlet temperature remains greater than the
inlet temperature.
Also, like appellants, we cannot understand how the
examiner allowed claim 1 but rejects claim 2 which recites
features in addition to those recited in claim 1.
We now turn to the examiner's § 102 rejection of claim 5
over U.K. '897. Claim 5 defines a gas chromatographic method
comprising a packed column "provided with a variable elution
temperature profile decreasing along the column length from
the inlet to the outlet of the column" (emphasis added). We
agree with the examiner that U.K. '897 discloses a separation
column in which the temperature gradient decreases in the
direction of the fluid flow through the column. However, as
urged by appellants, appealed claim 5 requires more than that,
i.e., the decreasing temperature profile must be variable (see
page 6 of present specification and Figure 3 for a description
of how appellants effect a variable, decreasing temperature
profile). The examiner has pointed to no disclosure in U.K.
'897 of a variable temperature profile, and our review of the
reference fails to reveal any such disclosure. Accordingly,
Appeal No. 95-5074
Application No. 08/186,900
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we agree with appellants that claim 5 is not properly rejected
under 35 U.S.C. § 102.
Regarding the rejections of claims 3, 4 (dependent on
claim 2) and 6-9 (dependent on claim 5) under 35 U.S.C. § 103,
since Cheh does not remedy the aforementioned deficiency of
Burow with respect to claim 2, or alleviate the deficiency of
U.K. '897 with respect to claim 5 (the examiner does not
assert such), and the examiner does not take the position that
Burow would have rendered obvious the provision of a variable,
decreasing temperature profile, we cannot sustain these
rejections.
In conclusion, based on the foregoing, the examiner's
decision rejecting the appealed claims is reversed.
REVERSED
EDWARD C. KIMLIN )
Administrative Patent Judge )
)
)
)
)
CAMERON WEIFFENBACH ) BOARD OF PATENT
Administrative Patent Judge ) APPEALS AND
) INTERFERENCES
)
)
)
Appeal No. 95-5074
Application No. 08/186,900
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JOAN ELLIS )
Administrative Patent Judge )
clm
Appeal No. 95-5074
Application No. 08/186,900
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