DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on January 19, 2026 has been entered.
Response to Amendment
This Office Action is in response to Applicant’s Amendment filed on January 19, 2026. Claim 1 has been amended. No new claims have been added. Claims 2-3, 9 and 11-17 have been canceled. Currently, claims 1, 4-8, 10 and 18-20 are pending.
Response to Arguments
Applicant’s arguments with respect to claim 1 have been considered but are moot as applied to the newly added claim limitations because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim 1, 4-8, 10 and 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Kawakami et al. (US 2022/0209136 A1; hereafter Kawakami) in view of Kim et al. (US 2014/0197386 A1; hereafter Kim 386’), Kim et al. (US 2015/0228909 A1; hereafter Kim 909’) and Yamazaki et al. (US 2020/0013968 A1; hereafter Yamazaki).
Regarding claim 1, Kawakami teaches an electroluminescent element (see e.g., light-emitting device shown in Figure 1A), comprising an electron transport layer, a green light-emitting layer and a hole transport layer laminated one on another (see e.g., electron-transport layer 114, light-emitting layer 113 which may include material that emits green phosphorescence and a hole-transport layer 112 overlaying each other, Paras [0045], [0070], Figure 1A), wherein the green light-emitting layer comprises a hole-type host material, an electron-type host material and a green guest light-emitting material (see e.g., the light-emitting layer 113 contains a host material and an emission center substance. The host material is composed of a plurality of organic compounds. The first organic compound has an electron-transport property and the second organic compound has a hole-transport property for easy adjustment of carrier balance, control of recombination region, and the like. The emission center substance may include a material that emits green phosphorescence, Paras [0061] – [0063], [0065], [0070]);
Kawakami does not explicitly teach
“wherein the hole-type host material comprises P1, and P1 is 9,9'-di ([[1,1'-biphenyl]-4- yl)-9H, 9 'H-3,3'-bicarbazole”;
In a similar field of endeavor Kim 386’ teaches
wherein the hole-type host material comprises P1, and P1 is 9,9'-di ([[1,1'-biphenyll-4- yl)-9H, 9 'H-3,3'-bicarbazole (see e.g., P1 hole type host material, Chemical Formula I-2 on page 13. The optoelectronic device comprising a first host represented by Chemical Formula A-1 and a second host represented by Chemical Formula B-1. The claimed P1 falls within the scope of Chemical Formula A-1 and the claimed N1 falls within the scope of Chemical Formula B-1).
Therefore, it would have been obvious to one skilled in the art at the time the invention was effectively field to implement Kim 386’s teachings of wherein the hole-type host material comprises P1, and P1 is 9,9'-di ([[1,1'-biphenyll-4- yl)-9H, 9 'H-3,3'-bicarbazole in the device of Kawakami in order to optimize the device and provide good luminescence characteristics.
Kawakami does not explicitly teach
“wherein the electron-type host material comprises N1, and N1 is 5-(4,6-diphenyl-1,3,5- triazin-2-yl)-9-phenyl-5, 9-dihydrothieno [2,3-b: 5,4-b '1 dicarbazole”;
In a similar field of endeavor Kim 909’ teaches
wherein the electron-type host material comprises N1, and N1 is 5-(4,6-diphenyl-1,3,5- triazin-2-yl)-9-phenyl-5, 9-dihydrothieno [2,3-b: 5,4-b '1] dicarbazole (see e.g., The N1 electron type host material, compound 155 on page 46. The OLED uses two host system, wherein one of the hosts is compound 155 and the other host is compound A2 nearly identical to the claimed P1 host (see Table 5 on page 96 and structure of compound A2 on page 95)).
Therefore, it would have been obvious to one skilled in the art at the time the invention was effectively filed to implement Kim 909’s teachings of wherein the electron-type host material comprises N1, and N1 is 5-(4,6-diphenyl-1,3,5- triazin-2-yl)-9-phenyl-5, 9-dihydrothieno [2,3-b: 5,4-b '1 dicarbazole in the device of Kawakami in order to optimize the device and provide good luminescence characteristics.
Kawakami does not explicitly teach
“a mass ratio of P1 to N1 is 6:4”
While Kawakami does not explicitly teach the specific mass ratio of P1 to N1 as 6:4, the selection of such ratios represents a routine optimization of parameters within the field of OLEDs. Kim 386 provides clear guidance in this regard, teaching that compounds represented by Chemical Formula A-1 and Chemical Formula B-1 may be mixed in a ratio ranging from 4:6 to about 6:4 (see e.g., para [0135])
Given that P1 and N1 fall squarely within the scope of Chemical Formula A-1 and Chemical Formula B-1, respectively therefore, it would have been obvious to apply the ratio taught by Kim 386 to the device of Kawakami.
Applicant has not demonstrated any criticality or unexpected results associated with the 6:4 ratio.
Therefore, it would have been obvious to one skilled in the art at the time the invention was effectively filed to implement a mass ratio of P1 to N1 is 6:4 in the device of Kawakami in order to optimize the device and provide good luminescence characteristics.
Kawakami does not explicitly teach
“wherein the green guest light-emitting material comprises a diphenylpyridine iridium metal complex containing a third substituent, and the third substituent comprises at least one of a heteroalkyl group and a heteroaryl group”.
In a similar field of endeavor Yamazaki teaches
wherein the green guest light-emitting material comprises a diphenylpyridine iridium metal complex containing a third substituent, and the third substituent comprises at least one of a heteroalkyl group and a heteroaryl group (see e.g., Ir(mdppy)2(5dptznmdppy) compound shown as example 10 on page 36).
Therefore, it would have been obvious to one skilled in the art at the time the invention was effectively filed to implement Yamazaki’s teachings of the green guest light-emitting material comprises a diphenylpyridine iridium metal complex containing a third substituent, and the third substituent comprises at least one of a heteroalkyl group and a heteroaryl group in the device of Kawakami in order to achieve a desired light color and improve the overall device performance.
Kawakami does not explicitly teach
“when a ratio of hole mobility of the hole-type host material to electron mobility of the electron-type host material is not greater than 1:1, a ratio of a first energy level difference to a second energy level difference is not greater than 1:1; and
the first energy level difference is a difference between a Highest Occupied Molecular Orbital (HOMO) energy level of the hole-type host material and an HOMO energy level of the green guest light-emitting material, and the second energy level difference is a difference between a Lowest Unoccupied Molecular Orbital (LUMO) energy level of the electron-type host material and an LUMO energy level of the green guest light-emitting material.
wherein a mass ratio of the hole-type host material to the electron-type host material is not less than 1:1 and not more than 4:1, and the ratio of the first energy level difference to the second energy level difference is not less than 1:4 and not more than 1:1;
wherein the ratio of the hole mobility of the hole-type host material to the electron mobility of the electron-type host material is not less than 1:100 and not greater than 1:1
wherein the hole mobility of the hole-type host material is not less than
1
x
10
-
8
c
m
2
/v-s and not more than
1
x
10
-
4
c
m
2
/v-s; or the electron mobility of the electron-type host material is not less than
1
x
10
-
8
c
m
2
/v-s and not more than
1
x
10
-
4
c
m
2
/v-s
wherein the HOMO energy level of the green guest light-emitting material is not less than 4.8 eV and not more than 5.2 eV; or the LUMO energy level of the green guest light-emitting material is not less than 2.4 eV and not more than 2.8 eV”.
Given that primary components, hole-type host, electron-type host and green guest, are known in the art, adjusting their relative mass ratios and mobility parameters constitutes a mere carrying forward of known principles to achieve a balanced recombination zone. The parameters defined, hole/electron mobility ratios, hole/electron mobilities and specific HOMO/LUMO levels represent predictable, routine adjustments to optimize device rather than unexpected results.
"[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). Furthermore, "[i]t is a settled principle of law that a mere carrying forward of an original patented conception involving only change of form, proportions, or degree, or the substitution of equivalents doing the same thing as the original invention, by substantially the same means, is not such an invention as will sustain a patent, even though the changes of the kind may produce better results than prior inventions." In re Williams, 36 F.2d 436, 438 (CCPA 1929).
Any differences between the claimed invention and the prior art may be expected to result in some differences in properties. The issue is whether the properties differ to such an extent that the difference is really unexpected. In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986) (differences in sedative and anticholinergic effects between prior art and claimed antidepressants were not unexpected). See MPEP 716.02.
Therefore, it would have been obvious to one skilled in the art at the time the invention was effectively filed to have when a ratio of hole mobility of the hole-type host material to electron mobility of the electron-type host material is not greater than 1:1, a ratio of a first energy level difference to a second energy level difference is not greater than 1:1; and
the first energy level difference is a difference between a Highest Occupied Molecular Orbital (HOMO) energy level of the hole-type host material and an HOMO energy level of the green guest light-emitting material, and the second energy level difference is a difference between a Lowest Unoccupied Molecular Orbital (LUMO) energy level of the electron-type host material and an LUMO energy level of the green guest light-emitting material.
wherein a mass ratio of the hole-type host material to the electron-type host material is not less than 1:1 and not more than 4:1, and the ratio of the first energy level difference to the second energy level difference is not less than 1:4 and not more than 1:1;
wherein the ratio of the hole mobility of the hole-type host material to the electron mobility of the electron-type host material is not less than 1:100 and not greater than 1:1
wherein the hole mobility of the hole-type host material is not less than
1
x
10
-
8
c
m
2
/v-s and not more than
1
x
10
-
4
c
m
2
/v-s; or the electron mobility of the electron-type host material is not less than
1
x
10
-
8
c
m
2
/v-s and not more than
1
x
10
-
4
c
m
2
/v-s
wherein the HOMO energy level of the green guest light-emitting material is not less than 4.8 eV and not more than 5.2 eV; or the LUMO energy level of the green guest light-emitting material is not less than 2.4 eV and not more than 2.8 eV in order to optimize the device and allow for easy adjustment of carrier balance, control of a recombination region, and the like.
Regarding claim 4, Kawakami, as modified by Kim 386’, Kim 909’ and Yamazaki, teaches the limitations of claim 1 as mentioned above. Kawakami does not explicitly teach
“wherein the hole mobility of the hole-type host material is not less than
1
x
10
-
8
c
m
2
/v-s and not more than
1
x
10
-
4
c
m
2
/v-s; and the electron mobility of the electron-type host material is not less than
1
x
10
-
8
c
m
2
/v-s and not more than
1
x
10
-
4
c
m
2
/v-s”.
"[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). Furthermore, "[i]t is a settled principle of law that a mere carrying forward of an original patented conception involving only change of form, proportions, or degree, or the substitution of equivalents doing the same thing as the original invention, by substantially the same means, is not such an invention as will sustain a patent, even though the changes of the kind may produce better results than prior inventions." In re Williams, 36 F.2d 436, 438 (CCPA 1929).
Any differences between the claimed invention and the prior art may be expected to result in some differences in properties. The issue is whether the properties differ to such an extent that the difference is really unexpected. In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986) (differences in sedative and anticholinergic effects between prior art and claimed antidepressants were not unexpected). See MPEP 716.02.
It would have been obvious to one skilled in the art at the time the invention was effectively filed to have the hole mobility of the hole-type host material is not less than
1
x
10
-
8
c
m
2
/v-s and not more than
1
x
10
-
4
c
m
2
/v-s; or the electron mobility of the electron-type host material is not less than
1
x
10
-
8
c
m
2
/v-s and not more than
1
x
10
-
4
c
m
2
/v-s in order to optimize the device and allow for easy adjustment of carrier balance, control of a recombination region, and the like.
Regarding claims 5 and 6, Kawakami, as modified by Kim 386’, Kim 909’ and Yamazaki, teaches the limitations of claim 1 as mentioned above. Kawakami does not explicitly teach
“wherein the HOMO energy level of the hole-type host material is not less than 5.3 eV and not more than 5.8 eV; or the HOMO energy level of the electron-type host material is not less than 5.5 eV and not more than 6.2 eV”.
"[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). Furthermore, "[i]t is a settled principle of law that a mere carrying forward of an original patented conception involving only change of form, proportions, or degree, or the substitution of equivalents doing the same thing as the original invention, by substantially the same means, is not such an invention as will sustain a patent, even though the changes of the kind may produce better results than prior inventions." In re Williams, 36 F.2d 436, 438 (CCPA 1929).
Any differences between the claimed invention and the prior art may be expected to result in some differences in properties. The issue is whether the properties differ to such an extent that the difference is really unexpected. In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986) (differences in sedative and anticholinergic effects between prior art and claimed antidepressants were not unexpected). See MPEP 716.02.
It would have been obvious to one skilled in the art at the time the invention was effectively filed to have the HOMO energy level of the hole-type host material is not less than 5.3 eV and not more than 5.8 eV; or the HOMO energy level of the electron-type host material is not less than 5.5 eV and not more than 6.2 eV in order to optimize the device and allow for easy adjustment of carrier balance, control of a recombination region, and the like.
Regarding claims 7 and 8, Kawakami, as modified by Kim 386’, Kim 909’ and Yamazaki, teaches the limitations of claim 1 as mentioned above. Kawakami does not explicitly teach
“wherein the LUMO energy level of the hole-type host material is not less than 2.0 eV and not more than 2.5 eV; or the LUMO energy level of the electron-type host material is not less than 2.2 eV and not more than 2.7 eV”.
"[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). Furthermore, "[i]t is a settled principle of law that a mere carrying forward of an original patented conception involving only change of form, proportions, or degree, or the substitution of equivalents doing the same thing as the original invention, by substantially the same means, is not such an invention as will sustain a patent, even though the changes of the kind may produce better results than prior inventions." In re Williams, 36 F.2d 436, 438 (CCPA 1929).
Any differences between the claimed invention and the prior art may be expected to result in some differences in properties. The issue is whether the properties differ to such an extent that the difference is really unexpected. In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986) (differences in sedative and anticholinergic effects between prior art and claimed antidepressants were not unexpected). See MPEP 716.02.
It would have been obvious to one skilled in the art at the time the invention was effectively filed to have the LUMO energy level of the hole-type host material is not less than 2.0 eV and not more than 2.5 eV; or the LUMO energy level of the electron-type host material is not less than 2.2 eV and not more than 2.7 eV in order to optimize the device and allow for easy adjustment of carrier balance, control of a recombination region, and the like.
Regarding claim 10, Kawakami, as modified by Kim 386’, Kim 909’ and Yamazaki, teaches the limitations of claim 1 as mentioned above. Kawakami does not explicitly teach
“wherein the HOMO energy level of the green guest light-emitting material is not less than 4.8 eV and not more than 5.2 eV; or the LUMO energy level of the green guest light-emitting material is not less than 2.4 eV and not more than 2.8 eV”.
"[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). Furthermore, "[i]t is a settled principle of law that a mere carrying forward of an original patented conception involving only change of form, proportions, or degree, or the substitution of equivalents doing the same thing as the original invention, by substantially the same means, is not such an invention as will sustain a patent, even though the changes of the kind may produce better results than prior inventions." In re Williams, 36 F.2d 436, 438 (CCPA 1929).
Any differences between the claimed invention and the prior art may be expected to result in some differences in properties. The issue is whether the properties differ to such an extent that the difference is really unexpected. In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986) (differences in sedative and anticholinergic effects between prior art and claimed antidepressants were not unexpected). See MPEP 716.02.
It would have been obvious to one skilled in the art at the time the invention was effectively filed to have the HOMO energy level of the green guest light-emitting material is not less than 4.8 eV and not more than 5.2 eV; or the LUMO energy level of the green guest light-emitting material is not less than 2.4 eV and not more than 2.8 eV in order to optimize the device and allow for easy adjustment of carrier balance, control of a recombination region, and the like.
Regarding claim 18, Kawakami, as modified by Kim 386’, Kim 909’ and Yamazaki, teaches the limitations of claim 1 as mentioned above. Kawakami further teaches a display panel, comprising a cathode layer, an anode layer and the electroluminescent element according to claim 1, wherein the cathode layer is located at a side of the electron transport layer away from the green light-emitting layer in the electroluminescent element, and the anode layer is located at a side of the hole transport layer away from the green light-emitting layer in the electroluminescent element (see e.g., light-emitting device as shown in Figure 1A. Cathode 102 is located at a side of electron-transport layer 114 and the anode 101 is located at a side of the hole-transport layer 112, Paras [0045] – [0046], Figure 1A).
Regarding claim 19, Kawakami, as modified by Kim 386’, Kim 909’ and Yamazaki, teaches the limitations of claim 1 as mentioned above. Kawakami further teaches a display device, comprising the electroluminescent element according to claim 1 (see e.g., the light-emitting device shown in Figure 1A may be used in a light-emitting apparatus shown in Figure 4, Para [0137]).
Regarding claim 20, Kawakami, as modified by Kim 386’, Kim 909’ and Yamazaki, teaches the limitations of claim 1 as mentioned above. Kawakami further teaches a display device, comprising the display panel according to claim 18 (see e.g., the light-emitting apparatus can be used in a display device for displaying images such as television display, computer, cellular phone etc. Para [0196], Figure 9).
Conclusion
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/FAKEHA SEHAR/Examiner, Art Unit 2893
/YARA B GREEN/Supervisor Patent Examiner, Art Unit 2893