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 .
This Office action is in response to the amendment filed 12/3/2025. Claims 1 and 20 are amended; claims 2-4, 6-7 and 15 are cancelled; claims 13-14 and 16-18 are withdrawn from consideration as being drawn to non-elected invention. Accordingly, claims 1, 5, 8-14 and 16-21 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 1,5, 8, 10 and 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over O’Hare et al (US 2017/0313793 A1) in view of Thorn et al (US 2005/0285284 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 Thorn et al, and hence the preamble fails to limit the claim. MPEP 2111.02.
Regarding claims 1, 5, 10, and 19, 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, Thorn et al in the same filed of endeavor, teach ansa-metallocene comprising bridged cyclopentadienyl and fluorenyl ligands (abstract). Metallocene compounds constitute useful catalyst components for variety of transformation including olefin polymerization (paragraph 0002). A variety of substituents can be incorporated into the ansa-metallocene structure, including substituents on the cyclopentadienyl-type ligands or the bridging group or both, each of which helps determine the physical properties of polyolefins prepared using these compounds (paragraph 0003). Examples of ansa-metallocene include compound of formula:
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(paragraph 0036) wherein R1 and R2 are independently selected from aliphatic or substituted aliphatic group having 1 to about 20 carbon atoms; M1 is Zr or Hf, X = Cl, Br or I; and R3 in each instance is aliphatic or substituted aliphatic group having 1 to about 20 carbon atoms (paragraphs 0053-0056) which reads on metallocene complex of formula (Va) and (Vb) in present claim 1, wherein Y = -WRy2-, W = C, Ry = linear C1-10 hydrocarbyl group, X = sigma ligand, R6 and R11 = C1-10 hydrocarbyl group; and X = halogen in present claims 5 and 19. Therefore, in light of the teachings in Thorn et al in the same filed of endeavor 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 Thorn 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, examples of zirconocene analogs, in Thorn et al, include compound of formula:
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(paragraph 0058) wherein R3 is H, t-butyl, i-propyl, ethyl or methyl, and n is an integer of from 1 to about 6 (paragraphs 0063-0064) which reads on R6 and R11 are tertiary alkyl group in present claim 20.
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 Thorn et al (US 2005/0285284 A1) and Kaji et al (US 2011/0282017 A1).
The discussion with respect to O’Hare et al and Thorn et al in paragraph 8 above is incorporated here by reference.
O’Hare et al and Thorn 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 Thorn 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 8-11, of office action mailed 8/7/2025, are withdrawn in view of amendment and/or applicant arguments and/or new grounds of rejection set forth in this office action, necessitated by amendment.
While the grounds of rejection are changed, it was still deemed appropriate to address some of the arguments which would be pertinent to new grounds of rejection in this office action (See paragraph 11 below).
Applicant's arguments filed 12/3/2025 have been fully considered but they are not persuasive. Specifically, applicant argues that (A) O’Hare and Thorn are not combinable because structure of metallocene complex, in O’Hare, in particular requires that complex comprise a per-methyl substituted indenyl ring (I*). This is supported by Table 6 of O’Hare, where the activity of the complexes lacking I* ligand is significantly lowered compared to a complex having I* ligand; (B) structure of metallocene complex is central to the invention of O’Hare. Therefore, simply replacing it with a completely different metallocene complex in the hope that the resulting catalyst system would exhibit the same properties is not obvious. Clearly, different metallocene complexes with distinct strictures exhibit different properties as confirmed by [0002] of Thorn; (C ) claim 1 requires more than just the catalyst system that is suitable for polymerizing olefins, it required the catalyst system for producing olefin polymers in high temperature solutions greater than 1000C. Suitability at solution conditions above 1000C is not inherent to all metallocene systems, as the art documents strong temperature dependencies in activity and comonomer incorporation. It is not obvious from the cited prior art therefore that combination of solid alkyl alumoxane catalyst taken from O’Hare and the metallocene complex taken from Thorn would even be suitable for producing ethylene copolymers in a high temperature solution.
With respect to (A), O’Hare and Thorn are combinable because O’Hare discloses unsymmetrical metallocene catalyst compound that are markedly more active in the polymerization of olefins. In fact, Table 6, shows that unsymmetrical metallocene compound (i.e., SB*Cp,I*)ZrCl2) exhibits higher activity compared to symmetrical metallocenes (i.e., nBuCP)2ZrCl2 and (Ind)2ZrCl2). Note that examples in Table 2 of O’Hare despite having I* in the symmetrical metallocene (i.e., [(EBI*)ZrCl2] and [(SBI*)ZrCl2]) exhibit lower activity compared to an unsymmetrical metallocene (i.e., [SB(tBu2Flu,I*)ZrCl2]).
With respect to (B), O’Hare teaches that activity of polymerization of olefins increases when unsymmetrical metallocenes are used compared to the use of symmetrical metallocenes (specifically, see Tables 2 and 6). O’Hare also teaches that solid MAO compositions exhibit significantly increased catalytic activity in the homopolymerization and copolymerization of α-olefins (paragraph 0061). Therefore, it is the Office’s position that it is within the scope of one skilled in art prior to the filing of present application to include an unsymmetrical metallocenes of Thorn in the catalyst system of O’Hare.
With respect to (C), O’Hare teaches that a person skilled in art of olefin polymerization will be able to select suitable reaction conditions (temperature) for such a polymerization reaction. Hence, it is the Office’s position that given that the catalyst system is obvious based on the disclosure in O’Hare combined with the teachings in Thorn, one skilled in art prior to the filing of present application would be able to select suitable temperature including greater than 1000C, absent evidence to the contrary.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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.
Contact Information
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.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
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