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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 4/29/2026 has been entered. Claims 1 and 19-20 are amended; claims 2-7 and 15 are cancelled; claims 13-14 and 16-18 are withdrawn from consideration as being drawn to non-elected invention; and claim 22 is added. Accordingly, claims 1, 8-14 and 16-22 are currently pending in the application.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1, 8, 10, 19-20 and 22 are rejected under 35 U.S.C. 103 as being unpatentable over O’Hare et al (US 2017/0313793 A1) in view of Canich et al (US 2017/0174798 A1).
Prior to setting forth the rejection, it is noted that the recitation of "for producing ethylene copolymers in a high temperature solution process at a temperature greater than 1000C " in the preamble (cf. independent claim 1) is deemed to be a statement of purpose or intended use which is not seen to result in any structural difference between the instantly claimed invention and O’Hare et al in view of Canich et al, and hence the preamble fails to limit the claim. MPEP 2111.02.
Regarding claims 1, 10, 19, and 22, O’Hare et al disclose catalyst compositions for use in olefin polymerization processes and comprising unsymmetrical metallocene catalyst compounds (abstract). See example 1, wherein the catalyst system comprises solid MAO/[Zr-Complex] catalyst suspended in hexane (paragraph 0232) which reads on solid alkyl aluminoxane provided as a suspension in an aliphatic C6 hydrocarbon in present claims 1 and 10. The Zr-complex includes [SB(tBu2Flu,I*)ZrCl2]) represented by formula:
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(paragraph 0231). It is noted that MAO reads on solid alkyl alumoxane wherein alkyl group is methyl (i.e., reads on C1-alkyl in present claim 1).
O’Hare et al differ with respect to the species of metallocene complex.
However, Canich et al in the same field endeavor teach novel hafnium-based metallocene catalyst compound with a fluorenyl ligand and a cyclopentadienyl ligand (abstract). Examples of catalyst compound that are particularly useful include compounds represented by formula:
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(paragraph 0084) which is an isomer of metallocene complex of formula Vb in present claim 1, wherein Y is bridge of formula -WRy2-, W = C, Ry = C6-aryl, X = C1-alkyl, R6 and R11 = C1-hydrocarbyl group; each X is R14 and R14 is C1-alkyl in present claim 19; and each Ry is independently a C6-aryl group in present claim 22. Case law holds that structural similarities have been found to support a prima facie case of obviousness. See, e.g., In re May, 574 F.2d 1082, 1093-95, 197 USPQ 601, 610-11 (CCPA 1978) (stereoisomers); In re Wilder, 563 F.2d 457, 460, 195 USPQ 426, 429 (CCPA 1977) (adjacent homologs and structural isomers). Therefore, in light of the teachings in Canich et al, case law, and given that O’Hare et al teach unsymmetrical catalysts comprising a fluorenyl ligand, it would have been obvious to one skilled in art prior to the filing of present application, to include a known unsymmetrical metallocene compound, of Canich et al, comprising fluorenyl ligand in the catalyst system of O’Hare et al, absent evidence to the contrary.
Regarding claim 8, see example 1, of O’Hare et al, wherein the catalyst system comprises solid MAO/[Zr-Complex] catalyst suspended in hexane (paragraph 0232) wherein MAO reads on solid alkyl alumoxane wherein alkyl group is methyl (i.e., reads on methyl alumoxane in present claim 8).
Regarding claim 20, in addition to 8a to 8c above, Canich et al teach that catalyst compound may be represented by the formula:
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wherein each R1, R2, R3, R6, R7, R8, R9, R10, R11 and R12 is independently hydrogen or a C1 to C10 alkyl each R4 and R5 is independently a C1 to C10 alkyl, J is SiR13R14 or (CR15R16)x where x = 1 or 2, R13 and R14 are each independently selected from the group consisting of substituted or unsubstituted hydrocarbyl group, R15 and R16 are each independently selected from the group consisting of substituted hydrocarbyl (paragraphs 0011 to 0014). R4 and R5 independently include methyl, butyl or isomers thereof (paragraph 0074). Each X is methyl (see claim 21) Therefore, in light of the teachings in Canich et al, it would have been obvious to one skilled in art prior to the filing of present application to prepare a catalyst composition, comprising an isomer of metallocene wherein R6 and R11 = t-butyl group and X = methyl, absent evidence to the contrary.
Claims 9, 11-12 and 21 are rejected under 35 U.S.C. 103 as being unpatentable over O’Hare et al (US 2017/0313793 A1) in view of Canich et al (US 2017/0174798 A1) and Kaji et al (US 2011/0282017 A1).
The discussion with respect to O’Hare et al and Canich et al in paragraph 8 above is incorporated here by reference.
O’Hare et al and Canich et al are silent with respect to aluminum content, average particle size of solid alkyl alumoxane cocatalyst; and content of solid AlkAO in the suspension.
However, Kaji et al in the same field of endeavor teach a solid polymethyl aluminoxane composition that has the form of relatively fine particles, has more uniform particle sizes and exhibits a high polymerization activity when used in the preparation of an olefin polymer (abstract). The solid polymethyl aluminoxane has extremely low solubility of 0 to 0.2 mol% in hexane at a temperature of 250C (paragraph 0066). The median diameter based on volume of the solid polymethyl aluminoxane is preferably 5 to 30 microns (paragraph 0061). A concentration of the polymethyl aluminoxane in the inactive hydrocarbon solvent is in the range of 6 to 30 wt% (paragraph 0080) which reads on the content of solid AlkAO in the suspension in present claim 12. See embodiment 1, wherein the solid polymethyl aluminoxane has an aluminum content of 37.3 mass% (i.e., reads on the Al content in present claim 9) and a particle size of 9.4 microns (paragraph 0132-0134). Therefore, in light of the teachings in Kaji et al and given that O’Hare uses a solid aluminoxane as a cocatalyst in its olefin polymerization process, it would have been obvious to one skilled in art prior to the filing of present application to include solid polymethyl aluminoxane of Kaji et al in the catalyst system, of O’Hare et al in view of Canich et al, for above mentioned advantages. Additionally, given that more uniform particle size is desired in Kaji et al and the median particle size falls within a narrow range of 5 to 30 microns and an exemplary embodiment has a median particle size of 9.4 microns, one skilled in art prior to the filing of present application would have a reasonable basis to expect the solid polymethyl aluminoxane to have an average particle size falling within the presently claimed range of 2 to 20 microns (i.e. reads on present claim 11) and 4 to 12 microns (i.e., reads on present claim 21), absent evidence to the contrary. Since, PTO cannot conduct experiments, the burden of proof is shifted to the applicants to establish an unobviousness difference, see In re Best, 562 F.2d 1252, 195 USPQ 430 (CCPA 1977).
Response to Arguments
The rejections under 35 U.S.C. 103 as set forth in paragraphs 8-9, of Office action mailed 2/5/2026, are withdrawn in view of amendments and/or applicant arguments and/or new grounds of rejection set forth in this Office action, necessitated by amendment.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KARUNA P REDDY whose telephone number is (571)272-6566. The examiner can normally be reached 8:30 AM to 5:00 PM M-F.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Arrie (Lanee) Reuther can be reached at 571-270-7026. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/KARUNA P REDDY/Primary Examiner, Art Unit 1764
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