Ex Parte Ju et al

Board of Patent Appeals and Interferences

Mar 30, 2009

10938464 (B.P.A.I. Mar. 30, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte SANG-HYUN JU, MU-HYUN KIM,
JANG-HYUK KWON, SUNG-CHUL KIM,
HO-KYOON CHUNG, BYUNG-DOO CHIN,
and SEONG-TAEK LEE
____________

Appeal 2009-0184
Application 10/938,464
Technology Center 1700
____________

Decided:1 March 30, 2009
____________

Before CHUNG K. PAK, JEFFREY T. SMITH, and
KAREN M. HASTINGS, Administrative Patent Judges.

PAK, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE

1 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 C.F.R. § 1.304, begins to run from the Decided Date
shown on this page of the decision. The time period does not run from the
Mail Date (paper delivery) or Notification Date (electronic delivery).
Appeal 2009-0184
Application 10/938,464

2
Appellants appeal under 35 U.S.C. § 134 from the Examiner’s
decision rejecting claims 1 through 6 and 9 through 11, all of the claims
pending in the above-identified application. We have jurisdiction under 35
U.S.C. § 6.
We AFFIRM.
The subject matter on appeal is directed to “a full color organic
electroluminescent device (OLED)” (Spec. 1, ll. 10-11). Details of the
appealed subject matter are recited in representative claim 12 reproduced
below:

1. A full color organic electroluminescent device, comprising:

a substrate;

a first electrode formed on the substrate;

an organic emitting layer formed on the first electrode, and having a
red-emitting layer, a green-emitting layer and a blue-emitting layer,
respectively patterned in a red pixel region, a green pixel region and a blue
pixel region, wherein each of the red and green-emitting layers comprises a
phosphorescent material and the blue-emitting layer comprises a fluorescent
material;

a hole blocking layer formed on the organic emitting layer as a
common layer; and

a second electrode formed on the hole blocking layer.

2 Appellants have presented substantive arguments directed to the limitations
set forth in claim 1 only. Therefore, for the purposes of this appeal, we limit
our discussion to claim 1 only pursuant to 37 C.F.R. § 41.37(c)(1)(vii)
(2007),
Appeal 2009-0184
Application 10/938,464

3
The Examiner rejected claims 1 through 6 and 9 through 11 under 35
U.S.C. § 103(a) as unpatentable over the disclosure of US. Patent 6,917,159
issued to Tyan et al. on July 12, 2005 (hereinafter referred to as “Tyan”).
Appellants contend that Tyan does not “teach or suggest the use of
phosphorescent materials for the red- and green-emitting layers and a
fluorescent material for the blue-emitting layer” in combination with a hole
blocking layer in a full color organic electroluminescent device as required
by the claims on appeal. (App. Br. 2-6 and Reply Br. 2-4.) Accordingly, it
is Appellants’ position that the Examiner erred in rejecting claims 1 through
6 and 9 through 11 under 35 U.S.C. § 103(a) as unpatentable over the
disclosure of Tyan.

ISSUE
Have Appellants identified any reversible error in the Examiner’s
determination that one of ordinary skill in the art would have been led to
employ phosphorescent “materials for the red- and green emitting layers and
a fluorescent material for the blue-emitting layer” in combination with a hole
blocking layer in a full color organic electroluminescent device within the
meaning of 35 U.S.C. § 103(a)?

FINDINGS OF FACT
The Factual Findings set forth below are supported by a
preponderance of the evidence:
1. Tyan illustrates a full-color microcavity OLED display device (Fig. 5,
col. 6, ll. 1-3, and col. 23, l. 37 to col. 24, l. 59).
2. Tyan teaches (col. 4, l. 49 to col. 5, l. 31) that:
Appeal 2009-0184
Application 10/938,464

4
[A] full-color microcavity OLED display device including red,
green, and blue subpixels and having improved luminance
efficiency and improved chromaticity of red, green, and blue
light emitted from corresponding subpixels, comprising:
a) a substrate;
b) a microcavity defined over one substrate surface by, in
sequence, a metallic bottom-electrode layer, an organic
electroluminescent (EL) medium structure, and a metallic top-
electrode layer,
wherein the microcavity has a different selected cavity length
for each of the red, green, and blue sub-pixels;
wherein one of the metallic electrode layers is light
transmissive and the other one is substantially opaque and
reflective;
…
Wherein the organic EL medium structure includes at least a
pixilated light-emitting layer comprised of at least one organic
host material and at least one different dopant material
dispersed in the least one host material in correspondence with
the red, green, and blue subpixels;
…
Wherein the at least one dopant material is selected to generate
red light, another at least one dopant material is selected to
generate green light, and another at least one dopant material is
selected to generate blue light in the light-emitting layer;

Wherein each of the at least one dopant materials is selected
from the class of fluorescent dyes consisting of …. or the class
of phosphorescent compounds consisting of …

3. Tyan teaches that the organic EL medium structure has at least one
light-emitting layer, but normally has several layers, such as a hole-injecting
layer, a hole-transporting layer, a light-emitting layer, an electron-
transporting layer, and an electron-injecting layer (col. 8, ll. 54-69).
4. Tyan teaches (col. 12, ll. 48-54) that:
Appeal 2009-0184
Application 10/938,464

5
OLEDs employing phosphorescent dopants often require
exciton or hole-blocking layers to help confine the excitons or
electron-hole recombination to the light-emitting layer
comprising the host(s) and dopant(s). In one embodiment, such
a blocking layer would be placed between the electron-
transporting layer and the light-emitting layer.

5. Appellants acknowledge that a full color OLED employing a
substrate, an anode electrode, an organic EL medium structure comprising a
hole blocking layer applied over red, green, and blue layers formed in the
pixel region, and an upper cathode electrode is known (Spec. 1-4).
6. Appellants have not proffered any factual evidence to show that the
claimed particular combination of phosphorescent and fluorescent materials
in red, green, and blue emitting layers imparts unexpected results.

PRINCIPLES OF LAW
Under 35 U.S.C. § 103, the factual inquiry into obviousness requires a
determination of: (1) the scope and content of the prior art; (2) the
differences between the claimed subject matter and the prior art; (3) the level
of ordinary skill in the art; and (4) secondary considerations, if any. Graham
v. John Deere Co., 383 U.S. 1, 17-18 (1966). According to KSR Int’l Co. v.
Teleflex, Inc., 127 S. Ct. 1727, 1740-41 (2007):
[A]nalysis [of whether the subject matter of a claim would have
been obvious] need not seek out precise teachings directed to
the specific subject matter of the challenged claim, for a court
can take account of the inferences and creative steps that a
person of ordinary skill in the art would employ.

See also DyStar Textilfarben GmbH & Co. Deutschland KG v. C.H.
Patrick Co., 464 F.3d 1356, 1361 (Fed. Cir. 2006) (“The motivation need
Appeal 2009-0184
Application 10/938,464

6
not be found in the references sought to be combined, but may be found in
any number of sources, including common knowledge, the prior art as a
whole, or the nature of the problem itself.”); In re Hoeschele, 406 F.2d 1403,
1406-407 (CCPA 1969) (“[I]t is proper to take into account not only specific
teachings of the references but also the inferences which one skilled in the
art would reasonably be expected to draw therefrom”). The common
knowledge attributable to one of ordinary skill in the art includes what was
admittedly known in the art by Appellants at the time of the invention. See
In re Nomiya, 509 F.2d 566, 570-71 (CCPA 1975) (The admitted prior art in
applicant’s Specification may be used in determining the patentability of a
claimed invention.); see also In re Davis, 305 F.2d 501, 503 (CCPA 1962).
The fact that a reference “discloses a multitude of effective
combinations does not render any particular formulation less obvious.”
Merck & Co., Inc. v. Biocraft Labs, 874 F.2d 804, 808 (Fed. Cir. 1989)
In re Corkill, 771 F.2d 1496, 1500 (Fed. Cir. 1985) (obviousness rejection of
claims affirmed in light of prior art teaching that “hydrated zeolites will
work” in detergent formulations, even though “the inventors selected the
zeolites of the claims from among ‘thousands’ of compounds”)); see also, In
re Susi, 440 F.2d 442, 445 (CCPA 1971) (obviousness rejection affirmed
where the disclosure of the prior art was “huge, but it undeniably include[d]
at least some of the compounds recited in appellant's generic claims and
[was] of a class of chemicals to be used for the same purpose as appellant's
additives”).
“[A] reference disclosure must be evaluated for all that it fairly
[teaches] and not only for what is indicated as preferred.” In re Bozek, 416
F.2d 1385, 1390 (CCPA 1969). “A reference may be said to teach away
Appeal 2009-0184
Application 10/938,464

7
when a person of ordinary skill, upon reading the reference, would be
discouraged from following the path set out in the reference, or would be led
in a direction divergent from the path that was taken by the applicant.” In re
Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994)
The burden is on Appellants to identify reversible error in the
appealed § 103 rejection. Cf. In re Kahn, 441 F.3d 977, 985-986 (Fed. Cir.
2006); see also 37 C.F.R. § 41.37(c)(1)(vii).
ANALYSES AND CONCLUSIONS OF LAW
Tyan teaches a full color organic electroluminescent device (a full
color OLED) comprising a substrate, a first electrode formed on the
substrate, an organic electroluminescent (EL) medium structure comprising
an organic light emitting layer formed on the first electrode, and a second
electrode formed on the organic electroluminescent (EL) medium structure.
Tyan also teaches that its organic light emitting layer has red, green, and
blue-emitting layers respectively patterned in a red pixel region, a green
pixel region, and blue pixel region.
Appellants contend that one of ordinary skill in the art would not have
been led to employ phosphorescent “materials for the red- and green
emitting layers and a fluorescent material for the blue-emitting layer” in
combination with a hole blocking layer in the full color organic
electroluminescent device. However, Tyan teaches that its pixilated light-
emitting layer used in the full color organic electroluminescent device
comprises at least one different dopant material dispersed in at least one
organic host material in correspondence with the red, green, and blue
subpixels. According to Tyan, the dopant materials employed in the red,
green, and blue subpixels can be selected from the class of fluorescent dyes
Appeal 2009-0184
Application 10/938,464

8
or the class of phosphorescent compounds. When the phosphorescent
compounds are used as the dopant materials, Tyan teaches (col. 12, ll. 48-
54) that:
OLEDs employing phosphorescent dopants often require
exciton or hole-blocking layers to help confine the excitons or
electron-hole recombination to the light-emitting layer
comprising the host(s) and dopant(s). In one embodiment, such
a blocking layer would be placed between the electron-
transporting layer and the light-emitting layer.

Given the above teachings, we concur with the Examiner that one of
ordinary skill in the art would have been led to employ phosphorescent
“materials for the red- and green emitting layers and a fluorescent material
for the blue-emitting layer” in combination with a hole blocking layer in the
full color organic electroluminescent device as required by claim 1within the
meaning of 35 U.S.C. § 103(a). See Merck & Co., Inc. v. Biocraft Labs, 874
F.2d at 808; see also Corkill, 771 F.2d at 1500 (obviousness rejection of
claims affirmed in light of prior art teaching that “hydrated zeolites will
work” in detergent formulations, even though “the inventors selected the
zeolites of the claims from among ‘thousands’ of compounds”); Susi, 440
F.2d at 445 (obviousness rejection affirmed where the disclosure of the prior
art was “huge, but it undeniably include[d] at least some of the compounds
recited in appellant's generic claims and [was] of a class of chemicals to be
used for the same purpose as appellant's additives”). As can be seen from
the disclosure of Tyan, both phosphorescent and fluorescent materials are
useful for generating red, green, and blue emitting layers.
On this record, Appellants have not proffered any factual evidence to
show that the claimed particular combination of phosphorescent and
Appeal 2009-0184
Application 10/938,464

9
fluorescent materials in red, green, and blue emitting layers imparts
unexpected results.
Accordingly, based on the factual findings set forth in the Answer and
above, we determine that the preponderance of evidence weighs most
heavily in favor of obviousness within the meaning of 35 U.S.C. § 103(a).3

ORDER
In view of the foregoing, the decision of the Examiner is affirmed.

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

AFFIRMED

PL Initial:
sld

3 Claim 1, by virtue of employing the limitation “comprises,” after the
claimed red, green, and blue-emitting layers, appears to encompass the
admittedly known full color organic electroluminescent device having red,
green, and blue-emitting layers containing both phosphorescent and
fluorescent materials described at pages 3 and 4 of the Specification.
Appeal 2009-0184
Application 10/938,464

10
CHRISTIE, PARKER & HALE, LLP
P.O. BOX 7068
PASADENA, CA 91109-7068