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 .
DETAILED ACTION
Claims 1and 4-12 of Y. Kim et.al. US 18/344,614 (06/29/2023) are pending. Claims 8-12 are withdrawn as directed to nonelected Groups (II)-(III). Claims 1 and 4-7 are under examination on merits and are rejected.
Election/Restrictions
Pursuant to the restriction requirement, Applicant elected Group I (now claims 1,4-7), without traverse, in the reply filed on 02/02/2026. Claims 8-12 drawn to Groups (II)-(III) are withdrawn from consideration pursuant to 37 CFR 1.142(b). Applicant cancelled claims 2-3 in the reply filed on 06/02/2026. The restriction requirement is maintained as FINAL.
Withdrawal Claim Rejections - 35 USC § 102
Rejection of claims 1-2 and 6-7 under 35 U.S.C. 102(a)(1) as being anticipated by H. G. Alt, et al, (1996). 522(1), Journal of organometallic chemistry, 39-54 (1996)(“Alt”) is withdrawn in view of the instant claim 1 has been amended with the limitation of “M is Hf” that cannot be met by the Alt precursor 31b recited in the 102 rejection made in the previous Office action, therefore, the rejection is withdrawn.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1and 4-7 are rejected under 35 U.S.C. 103 as being unpatentable over by H. G. Alt, et al, (1996). 522(1), Journal of organometallic chemistry, 39-54 (1996)(“Alt”). Alt is published in German, a copy of machine translation is attached as the second part of the reference, which results the full reference has a total page of 31, the format for citation of the reference as XX/31.
H. G. Alt, et al, (1996). 522(1), Journal of organometallic chemistry, 39-54 (1996)(“Alt”)
As mentioned in the previous Office action that Alt teaches metallocene complexes catalyst precursors for the syndiospecifi polymerization of propylene. The catalyst are substituted in the positions of 2 and 7 of the fluorenylidene fragment by MeO-,halogen-, alkyl- and aryl group. Alt at page 1/31, Abstract and Fig. 2 at page 7/31.
Alt compared the catalytic functions of the synthesized metallocene complexes catalyst precursors and teaches that substituted groups at the 2 and 7 positions of the fluorenylidene fragment effect the catalytic activities of the metallocene complexes catalyst precursors; activity and molar mass of the polymer increase in the series Me<sub>Ph </sub> <tert-butyl < mesityl for the isopropylidene-bridged catalysts and Me<sub>Ph</sub> < tert-butyl <PhMe2C for the diphenylmethylene-bridged catalysts. Alt at page 26/31, paragraph 2 under Table 4, line 9-10, emphasis added.
Alt teaches that the metallocene complexes catalyst precursor 31b that has a chemical structure as indicated below. Alt at page7/31, Fig. 2., compound 31b.
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Per Table 5, Alt teaches that the catalyst precursor 31b was used for the bulk polymerization of propylene. Alt at page 10/31 and 26/31 Table 5 and page 25/31, right col. 2.5. Polymerization of Propylene and Comparison of Catalytic Properties, line 1-3.
Alt teaches that the catalyst was prepared as follows:
3.10.1. Preparation of the Catalyst
The respective metallocene dichloride complex was weighed (usually 1-2 mg ± 0.1 mg) and activated under an argon atmosphere with MAO (usually 1 ml MAO (30%) per 1 mg metallocene dichloride complex). The solution was diluted 2-10 times with toluene. 10 ml of each of these solutions were used for polymerization within 60 minutes.
Alt at page 31/31 left. col. 3.10.1. Preparation of the Catalyst, emphasis added.
Thus, Alt also teaches a composition comprising the catalyst precursor 31b and Methyl aluminoxane (MAO).
Alt further teaches that:
The hafnium compounds 26c and 30c are about half as active as the analogous zirconia complexes 26b and 30b, but the number of chain terminations is not as high and the molecular weight of polypropylene is significantly higher.
Alt at page 26/31, paragraph 2 under Table 4, last sentence to page 27/31, left col. line 4, emphasis added.
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See Alt Fig. 2 at page 7/31 and Table 5 at page 26/31.
Thus, Alt clearly teaches one ordinary skill in the art that molecular weight of a polymer produced with precursor comprising metal Hf is significantly higher than those produced with precursor comprising metal Zr when they have the same ligand(s).
The Alt teaches catalyst precursor 31b maps the Chemical Formula 1 in claims 1as:
Both R1 and R2 are 1-methyl-1-phenylethyl group that is a (C6-C12)aryl(C1-C10)alkyl;
Both R3 and R4 are phenyl group that is a (C6-C12)aryl;
Both X1 and X2 are chloride;
Difference Between Alt and Claims 1, 4-7
The Alt the complex 31b differs from the instant claims only in that the Zr metal is not the claimed Hf.
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Obviousness Rationales of the Claims 1,4-7
Obviousness of a claimed compound can also be supported where there is motivation to substitute particular chemical moieties in a prior art compound for others so as to arrive at a claimed compound. MPEP § 2143(I)(B). For example, in the pharmaceutical arts, the rational is stated as motivation to select a known compound and also motivation to structurally modify the selected compound in a particular way to achieve a claimed compound. MPEP § 2143(I)(B) (see for example, MPEP § 2143(I)(B) Example 9, citing Eisai Co. Ltd. v. Dr. Reddy’s Labs., Ltd., 533 F.3d 1353, 87 USPQ2d 1452 (Fed. Cir. 2008).
Claims 1 and 4-5 are obvious because one of ordinary skill seeking polypropylene having higher molecular weight is motivated to modify the Alt the complex 31b as indicated below, thus arrive at the first claimed species of claim 5, which meets each and every limitation of claims 1 and 4-5, therefore claims 1 and 4-5 are obvious.
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One ordinary skill has a motivation to do so with a reasonable expectation of success because Alt teaches that:
(i). polypropylene formed under the catalyzation of hafnium compounds has higher molecular weight than polypropylene formed under the catalyzation of zirconium compounds when they have the same ligand(s) ; and
(ii). the complex 31b is one of the two disclosed precursors having best catalytic activities.
Rationales supporting the modification is simple substitution of one known element for another to obtain predictable results. MPEP 2143. I (B).
Claims 6-7 are also obvious because one ordinary skill in the art is also motivated to include the proposed compound into a composition comprising methyl aluminoxane (MAO) to prepare a catalyst for polypropylene production. As mentioned in the previous Office action that the preamble language of “for producing a copolymer of ethylene and a-olefin” is interpreted as intended using rather claim limitation. MPEP 2111.02.(II).
Applicant’s Argument
Applicant argues that the amended claim 1 is not obvious over Alt on the ground that the claimed metal compound of amended claim 1 is a hafnium compound in which (C6-C12)aryl(C1-C10)alkyl is introduced at positions 2 and 7 of the fluorene moiety, which stabilizes the catalytic active point to realize excellent catalytic activity and enables the preparation of copolymers with high molecular weight in a high-temperature solution polymerization process. Remarks at page 3, Rejection under 35 USC § 103, to page 5, paragraph 4.
This argument is not persuasive because as mentioned in the rejection above that Alt teaches
(i).introducing of PhMe2C groups to the 2 and 7 positions of the fluorenylidene fragment would results best catalytic activity of the compared diphenylmethylene-bridged metallocene complexes catalyst precursors (see Alt at page 26/31, paragraph 2 under Table 4, line 9-10 and table 5 at page 10/31); and
(ii). polypropylene formed under the catalyzation of hafnium compounds has higher molecular weight than polypropylene formed under the catalyzation of zirconium compounds (See Alt at page 26/31, paragraph 2 under Table 4, last sentence to page 27/31, left col. line 4).
Which can be exampled with complex 26b, 26c and 31b as indicated below.
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Given Alt teaches the complex 31b comprising Zr as the metal has a very good catalytic activity, one ordinary skill in the art seeking polypropylene with higher molecular weight is motivated to modify the Alt complex 31b by replacing Zr with Hf with a reasonable expectation of success, therefore, the amended claim is obvious over Alt.
Applicant’s Argument Regarding Unexpected Results
Applicant argues that by selecting Hf as the central metal in the same ligand framework, polymer properties having a low MI and a low density, which would have been difficult to predict from the Zr catalyst of Alt, can be achieved. Remarks at page 5, paragraph 5 to page 8, paragraph 4.
Relevant Sections of the MPEP
A greater than expected result and evidence of unobvious or unexpected advantageous properties are evidentiary factors pertinent to the legal conclusion of obviousness of the claims at issue. MPEP § 716.02(a)(I)/(II). However, the burden is on Applicant to establish that the evidence relied upon demonstrates that the differences in results are in fact unexpected and unobvious and of both statistical and practical significance. MPEP § 716.02(b). Evidence of unexpected properties may be in the form of a direct or indirect comparison of the claimed invention with the closest prior art which is commensurate in scope with the claims. MPEP § 716.02(b)(III).
Furthermore, whether the unexpected results are the result of unexpectedly improved results or a property not taught by the prior art, the objective evidence of nonobviousness must be commensurate in scope with the claims which the evidence is offered to support; that is, the showing of unexpected results must be reviewed to see if the results occur over the entire claimed range. MPEP § 716.02(d). The nonobviousness of a broader claimed range can be supported by evidence based on unexpected results from testing a narrower range if one of ordinary skill in the art would be able to determine a trend in the exemplified data which would allow the artisan to reasonably extend the probative value thereof. MPEP § 716.02(d)(I).
Further, an affidavit or declaration under 37 CFR 1.132 also must compare the claimed subject matter with the closest prior art to be effective to rebut a prima facie case of obviousness. MPEP § 716.02(e).
The Results Proffered in the filed Declaration
Applicant submits the Declaration of inventor Young Seub Kim filed under 37 CFR § 1.132 (06/02/2026) to provide proffered results between the claimed complex and the Alt complex 31b.
The declaration states that:
6. [Polymerization Experiment] 1 L of hexane and 0.5 ml of l M TIBA (triisobutylaluminum) were added to a 4 L reactor at room temperature, and then 100 mL of 1-octene was added. Thereafter, the catalysts were weighed in a glove box. The catalyst of the present invention, which is an example of amended claim 1 (Cat. A), and the catalyst of Alt (Cat. B) were used in amounts of 3.9 μmol and 0.5 μmol, respectively, and each catalyst was diluted in 5 mL of TIBA (0.1 M in Hex). An additional 5 mL of hexane was mixed with each diluted catalyst solution, and the resulting solution was injected into the reactor through an inlet of the reactor.
7. In addition, anilinium tetrakis(pentafluorophenyl)borate was weighed in the glove box. When the catalyst of the present invention (Cat. A) was used, 19.5 μmol of anilinium tetrakis(pentafluorophenyl)borate was diluted in 5 mL of hexane, and when the catalyst of Alt (Cat. B) was used, 2.5 μmol of anilinium tetrakis(pentafluorophenyl)borate was diluted in 5 mL of hexane. Each diluted solution was injected into the reactor through the same inlet.
The Declaration at 6-7, emphasis added.
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The declaration also states that:
10. As shown in Table 1 above, when the Hf catalyst of the present invention
(Cat. A) was used, the resulting polymer exhibited a melt index (Ml) of 0.06 and a density of 0.8617 g/mL. In contrast, when the Zr catalyst of Alt (Cat. B) was used, the resulting polymer exhibited an MI of 0.520 and a density of 0.9042 g/mL.
11. When the central metal was changed from Zr (Cat. B) to Hf (Cat. A) while maintaining the same ligand structure, the MI was significantly reduced from 0.520 to 0.06, indicating a tendency toward higher molecular weight. In particular, the hafnium catalyst of the present invention (Cat. A) resulted in a significantly lower density of 0.8617 g/m L, thereby forming an excellent low-density copolymer at an elastomer level. In contrast, the
zirconium catalyst of Alt (Cat. B) resulted in a density of 0.9042 g/mL.
12. This demonstrates that, unlike the Zr-centered catalyst of Alt, the Hf-centered catalyst of the present invention can form an ethyleneil-octene copolymer having both a low melt index and a low density. ln particular, the decrease in density suggests a difference in the degree of incorporation of the 1--octene comonomer or formation of a branched structure, and thus relates not merely to a difference in catalytic activity, but to a difference in the structural properties of the resulting polymer.
The Declaration at 10-12.
The Proffered Results Do Not Overcome the § 103 Rejection Because Applicant Has Not Met Its Burden of Demonstrating that the Proffered Result Is Unexpected
Regarding the difference in melt index, the specification teaches that:
[0108] Melt flow rate (MFR) analysis was performed by melting plastic at 190°C and measuring a weight of an extrudate flowing through a capillary (orifice) having a certain size at loads of 2.16, 5, and 21.6 kg for 10 minutes. MFR was expressed as a melt index (MI) (g/10 min) according to the ASTM D1238 measurement standard. When MI was low, the molecular weight increased and flowability was reduced, such that processability was reduced and physical properties were improved.
Specification at page 25, [0108], emphasis added.
Thus, one ordinary skill in the art knows that melt flow rate of a polymer has an inverse relationship with its molecular weight: polymers with higher molecular weight would has a lower melt index.
As mentioned in the 103 rejection above that Alt clearly teaches one ordinary skill in the art that molecular weight of a polymer produced with precursor comprising metal Hf is significantly higher than those produced with precursor comprising metal Zr when they have the same ligand(s), therefore, it is expected that the molecular weight of polymer produced with the proposed precursor would significantly higher than those produced with the Alt precursor 31b; it is also expected that the melt flow rate (MFR) of polymer produced with the proposed precursor would significantly less than those produced with the Alt precursor 31b. Applicant does not provide persuasive evidence to show it is unexpected.
Regrading density of the formed polymers, it should be noted that the comparative experiments are not conducted at the similar condition as 19.5 μmol of co-catalyst anilinium tetrakis(pentafluorophenyl)borate was used with the Hf catalyst (Cat. A) while only 2.5 μmol of catalyst anilinium tetrakis(pentafluorophenyl)borate was used with the Zr catalyst (Cat. B). See The Declaration at 7. The data from Table 1 of the specification indicates that even at the same condition (same temperature, same catalyst precursor) with same amount but different co-catalyst [anilinium tetrakis(pentafluorophenyl)borate vs Trityl tetrakis(pentafluorophenyl)borate], the produced polymer has different density. See Table 1 at page 40-41 of the specification. The Example 1-2 and 3-4 in the Table 1 of the specification also indicates that polymers formed with anilinium tetrakis(pentafluorophenyl)borate as the co-catalyst has less density than those formed with trityl tetrakis(pentafluorophenyl)borate as the co-catalyst . See Table 1 at page 40-41 of the specification. Given 19.5 μmol of co-catalyst was used with the Hf catalyst (Cat. A) while only 2.5 μmol of co-catalyst was used with the Zr catalyst (Cat. B) in the comparative experiment, Applicant does NOT provide any evidence to prove the density difference between the formed polymer is not caused by significant different amount of co-catalyst used in the experiments rather the difference of the metal in the precursor.
Further, each polymer has different density, Applicant has provided NO explanation of why the density difference (0.8617 vs 0.9042) is unexpected and unobvious and of both statistical and practical significance. MPEP § 716.02(b). Applicant has therefore not met its burden. MPEP § 716.02(b). The burden is on Applicant to establish that the evidence relied upon demonstrates that the differences in results are in fact unexpected and unobvious and of both statistical and practical significance. MPEP § 716.02(b).
The Proffered Results Do Not Overcome the § 103 Rejection Because the Proffered Results are Not Commensurate in Scope with the Claims
Whether the unexpected results are the result of unexpectedly improved results or a property not taught by the prior art, the objective evidence of nonobviousness must be commensurate in scope with the claims which the evidence is offered to support; that is, the showing of unexpected results must be reviewed to see if the results occur over the entire claimed range. MPEP § 716.02(d). Herein, the only one species of the claimed Formula 1 is clearly not commensurate in scope with the large genera of Formula 1 claimed by the claim 1.
Applicant also argues that the catalyst of the present invention would overcome molecular-weight reduction under severe high-temperature conditions of 140°C or higher and produce a polymer having an extremely high molecular weight. Remarks at page 8, paragraph 5-6. This argument is not persuasive because Applicant argues something not be claimed. Further, the instant specification does not provide evidence to show the argued temperature is critical for using the claimed compound as catalyst precursor.
Applicant further argues on the ground that (i). Alt teaches away from the present invention, and (ii). person skilled in the art would not have been motivated to replace zirconium with hafnium based on Alt, which teaches that such replacement would result in reduced activity. Remarks at page 9. These argument have been fully considered but not persuasive for the follows reasons:
(i). while Alt teaches that hafnium compounds are about half as active as the analogous zirconia compounds, however, Alt teaches that catalytic activity of the compound 31b is very higher (72.7) which is more than two times of that of the Hf compound 26b(35.4), therefore, one ordinary skill in the art would be appraised that replacing the Zr in the Alt compound 31b with Hf can obtain a compound with acceptable catalytic activity while it less than that of the Alt compound 31b.
(ii). Alt teaches that polypropylene formed under the catalyzation of hafnium compounds has higher molecular weight than polypropylene formed under the catalyzation of zirconium compounds.
Therefore, one of ordinary skill seeking polypropylene having higher molecular weight is still motivated to modify the Alt the compound 31b by replacing Zr with Hf as proposed in the rejection with a reasonable expectation of success.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to FRANK S. HOU whose telephone number is (571)272-1802. The examiner can normally be reached 6:30 am-2:30 pm Eastern on Monday to Friday.
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/FRANK S. HOU/Examiner, Art Unit 1692
/ALEXANDER R PAGANO/Primary Examiner, Art Unit 1692
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