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 .
Election/Restrictions
Applicant’s election without traverse of Group II, Claims 7-14 in the reply filed on 9/4/2026 is acknowledged.
Claims 1-6, 15, and 16 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 9/4/2026.
Claim Interpretation
Claim 7 pertains to a method for preparing the monomer composition of claim 1. The structural features of claim 1 are construed as limiting the scope of the method claim, whereby the protocol of claim 7 requires that one prepare a composition with the color/impurity characteristics of claim 1. MPEP 2111.02.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 7-14 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 7 requires the structural features of claim 1 by reference. In this regard, the scope of the claim is unclear as there is insufficient delineation between the “aromatic diol compound” and “aromatic diol compound derivative” terminology. It is unclear what the full metes and bounds of the term “derivative” is within the context of the claim and which compounds fall within and outside the term. The lack of an explicit definition of what does, or does not, constitute a “derivative” within the specification is noted, particularly in what manner the “derivative” serves to differ in scope from an “aromatic diol compound”. Per MPEP 2173.04, a broad claim is not indefinite merely because it encompasses a wide scope of subject matter provided the scope is clearly defined. But a claim is indefinite when the boundaries of the protected subject matter are not clearly delineated and the scope is unclear. For example, a genus claim that covers multiple species is broad, but is not indefinite because of its breadth, which is otherwise clear. But a genus claim that could be interpreted in such a way that it is not clear which species are covered would be indefinite (e.g., because there is more than one reasonable interpretation of what species are included in the claim).
Claim 7 uses the terminology “glycol-based compound”. It is unclear what is meant or implied by the modifier “based” and how such compounds deviate otherwise from “glycol compounds”. The lack of an explicit definition of what does, or does not, constitute a “based” compound within the specification is noted. Accordingly, the intended scope of the claim is unclear.
Per claim 1, the monomer composition is recovered from a “polycarbonate-based resin”. Claim 7 requires depolymerization of “polycarbonate”. It is unclear whether or not these terms are meant to be one in the same. It is unclear what is meant or implied by the modifier “based” and how such polycarbonates deviate otherwise from “polycarbonates”.
As claims 8-14 depend from claim 7, they are rejected for the same issues discussed above.
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.
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.
Claim(s) 7-12 and 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Nikje (Polimery 2011, 56, nr 5, 381-384) in view of Hu (Polymer, 1998, 39, 16, 3841-3845) and Ishikawa (WO 2021/054300 A1). As the cited WO document is in a non-English language, the English equivalent, US 2022/0298300 A1 has been utilized in place of the WO document. All citations are made with respect to the above-mentioned US document.
Regarding Claims 7-9 and 12, Nikje describes processes of glycolyzing polycarbonates (Abstract) and describes embodiments where polycarbonate, ethylene glycol, and NaOH catalyst are combined and stirred to obtain bisphenol A (Recycling process of Page 382). Nikje teaches the obtained bisphenol A is recrystallized in water so as to be spectroscopically equivalent to standard BPA samples (Recycling process of Page 382) whereby the NMR spectrum suggests less than 10 mol% of impurities (Figures 1 and 2). Nikje differs from the subject matter claimed in that organic solvent and b* values are not described.
With respect to organic solvent, Hu teaches the use of co-solvents during base-catalyzed depolymerization of polycarbonates with alcohols is known (Abstract). Hu notes the further inclusion of solvent such as toluene or dioxane facilitates the dissolution of polycarbonate material and ultimately yields shorter reaction times (Page 3842). It would have been obvious to one of ordinary skill in the art to utilize co-solvents such as toluene or dioxane within the reaction mixtures of Nikje because doing so would aid polycarbonate dissolution/depolymerization in accordance with the teachings of Hu. While it is recognized claim 7 requires that organic solvent be mixed with polycarbonate first and followed by glycol and base, it has been held that the selection of any order of mixing ingredients is prima facie obvious in the absence of a showing of criticality with respect to the order claimed. MPEP 2144.04(IV)(C). In light of the cited case law therein, it would have been obvious to one of ordinary skill in the art that any order of mixing ingredients, inclusive of mixing organic solvent and polycarbonate first and followed by glycol and base, can be performed within the protocols of the prior art to predictably afford bisphenol A monomers for re-use in the absence of evidence of criticality with respect to the order claimed.
With respect to b*, Ishikawa teaches it was known in the art the color/impurities of polycarbonate monomers such as of bisphenol A have a considerable impact on the coloration of the resulting polycarbonate resin and can be removed via purification (Figure 1; ¶ 83-87; 140-143). It would have been obvious to one of ordinary skill in the art to purify the bisphenol A obtained by Nikje so as to obtain a low b* such as 0.01 to 2, because doing so would improve the hue of polycarbonate resins when re-used as taught by Ishikawa.
Regarding Claim 10, Hu teaches alcohol/solvent ratios within the scope of the claims (Table 1). Alternatively, Hu teaches the relative quantity of organic solvent and alcohol directly impacts depolymerization time (Table 1). Thus, the relative ratio of solvent/glycol is seen to be a result effective variable subject to routine optimization by one of ordinary skill in the art. See MPEP 2144.05(II). Case law holds that “discovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art.” See In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). In view of this, it would have been obvious to one of ordinary skill in the art to discover workable/optimal glycol/solvent ratios within the scope of the present claims so as to produce desired end results.
Regarding Claim 11, Nikje teaches the use of 1 wt% NaOH catalyst in a 6.4:1.27 mixture of glycol:polycarbonate (Page 382), equivalent to roughly 6.1 pbw catalyst per 100 pbw polycarbonate.
Regarding Claim 14, Nikje teaches the resulting mixture is added to water, after which BPA is precipitated/filtered, recrystallized in water, and then filtered (Page 382).
Claim(s) 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Nikje (Polimery 2011, 56, nr 5, 381-384) in view of Hu (Polymer, 1998, 39, 16, 3841-3845), Ishikawa (WO 2021/054300 A1), and Gorman (WO 2020/257234 A1). As the cited WO document is in a non-English language, the English equivalent, US 2022/0298300 A1 has been utilized in place of the WO document. All citations are made with respect to the above-mentioned US document.
The discussion regarding Nikje, Hu, and Ishikawa within ¶ 15-20 is incorporated herein by reference.
Regarding Claim 14, to the extent Nikje differs from the subject matter claimed in that purificiation via crystallization solvent is not described, Gorman also pertains to the isolation of bisphenol A via polycarbonate depolymerization from alcohol/co-solvent mixtures (Abstract). Gorman teaches it was known purified bisphenol A crystals can be achieved via addition of acidic water mixtures, upon which bisphenol A crystalizes out and can be isolated via filtration (¶ 26). Second recrystallizations can occur with other solvent mixtures afterwards (¶ 26). Gorman notes such protocols gives bisphenol A purities in excess of 99.8% (¶ 28). It would have been obvious to one of ordinary skill in the art to inject bisphenol A product into the crystallization solvents of Gorman and subsequently filtering said crystals, thereby predictably affording bisphenol A of high purity in accordance with the teachings of Gorman.
Claim(s) 7-13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Iannone (J. Mol. Cat. A: Chem. 2017, 425, 107-116; cited 1/25/2024) in view of Ishikawa (WO 2021/054300 A1). As the cited WO document is in a non-English language, the English equivalent, US 2022/0298300 A1 has been utilized in place of the WO document. All citations are made with respect to the above-mentioned US document.
Regarding Claims 7-9, Iannone describes processes of depolymerizing polycarbonates (Abstract) and describes embodiments where polycarbonate, propylene glycol, tetrahydrofuran, and ZnO catalyst (inorganic base catalyst) are combined and stirred to obtain bisphenol A (Table 1). Polycarbonate is first added to THF to form mixed solution, after which catalyst and nucleating agent (glycol) is added/stirred (Section 2.3 of Page 108). Near 100% conversion/selectivity is reported (Table 1), suggesting less than 10 mol% of impurities. Iannone differs from the subject matter claimed in that b* values are not described.
Ishikawa teaches it was known in the art the color/impurities of polycarbonate monomers such as of bisphenol A have a considerable impact on the coloration of the resulting polycarbonate resin and can be removed via purification (Figure 1; ¶ 83-87; 140-143). It would have been obvious to one of ordinary skill in the art to purify the bisphenol A obtained by Iannone so as to obtain a low b* such as 0.01 to 2, because doing so would improve the hue of polycarbonate resins when re-used as taught by Ishikawa.
Regarding Claim 10, Iannone teaches 5 mL of THF (~ 4.44 g) relative to 1.06 g of glycol (Table 1), equivalent to a 4.2:1 ratio.
Regarding Claim 11, Iannone describes embodiments where 1 mmol / 0.254 g of polycarbonate is used with 5 mol% ZnO catalyst (molecular weight: 81.4 g/mol), equivalent to roughly 1.6 pbw catalyst per 100 pbw polycarbonate.
Regarding Claim 12, Iannone teaches embodiments where NaOH is used (Table 1).
Regarding Claim 13, Iannone teaches embodiments where stirring occurs at 100 degrees C for 3-7 hours (Table 1).
Claim(s) 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Iannone (J. Mol. Cat. A: Chem. 2017, 425, 107-116; cited 1/25/2024) in view of Ishikawa (WO 2021/054300 A1) and Nikje (Polimery 2011, 56, nr 5, 381-384). As the cited WO document is in a non-English language, the English equivalent, US 2022/0298300 A1 has been utilized in place of the WO document. All citations are made with respect to the above-mentioned US document.
The discussion regarding Iannone and Ishikawa within ¶ 25-30 is incorporated herein by reference.
Regarding Claim 14, Iannone differs from the subject matter claimed in that purificiation via crystallization solvent is not described. Nikje also pertains to the depolymerization of polycarbonates with glycols (Abstract; Recycling process of page 382). Nikje notes after depolymerization, obtained bisphenol A can be precipitated with water and then subject to further recrystallization and filtration for purification (Page 382). It would have been obvious to one of ordinary skill in the art to inject the bisphenol A product obtained from Iannone into water crystallization solvent, recrystallized, and filter, because doing so would afford purified bisphenol A crystals as taught by Nikje.
Claim(s) 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Iannone (J. Mol. Cat. A: Chem. 2017, 425, 107-116; cited 1/25/2024) in view of Ishikawa (WO 2021/054300 A1) and Gorman (WO 2020/257234 A1). As the cited WO document is in a non-English language, the English equivalent, US 2022/0298300 A1 has been utilized in place of the WO document. All citations are made with respect to the above-mentioned US document.
The discussion regarding Iannone and Ishikawa within ¶ 32-33 is incorporated herein by reference.
Regarding Claim 14, Iannone differs from the subject matter claimed in that purificiation via crystallization solvent is not described. Gorman also pertains to the isolation of bisphenol A via polycarbonate depolymerization from alcohol/co-solvent mixtures (Abstract). Gorman teaches it was known purified bisphenol A crystals can be achieved via addition of acidic water mixtures, upon which bisphenol A crystalizes out and can be isolated via filtration (¶ 26). Second recrystallizations can occur with other solvent mixtures afterwards (¶ 26). Gorman notes such protocols gives bisphenol A purities in excess of 99.8% (¶ 28). It would have been obvious to one of ordinary skill in the art to inject bisphenol A product into the crystallization solvents of Gorman and subsequently filtering said crystals, thereby predictably affording bisphenol A of high purity in accordance with the teachings of Gorman.
Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claims 7-14 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-5 and 11-14 of copending Application No. 18/728,840. Although the claims at issue are not identical, they are not patentably distinct from each other.
Specifically, claim 1 of ‘840 pertains to a method of depolymerizing polycarbonates with alkylene glycol using substantially the same protocol instantly claimed. The same base catalysts are taught at claim 11. The same depolymerization conditions are also used (Claim 12). Since the same materials and procedure is being performed, it stands to reason the claimed content of derivative impurity and b* characteristics in the obtained aromatic diol is necessarily present in the absence of evidence to the contrary. Therefore, the ‘840 claims anticipate the present claims. The remaining limitations claimed are found within the ‘840 claims.
This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Claims 7-9 and 12-14 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 13-18 of copending Application No. 18/728,854. Although the claims at issue are not identical, they are not patentably distinct from each other.
Specifically, claim 13 of ‘854 pertains to a method of depolymerizing polycarbonates with alkylene glycol using substantially the same protocol instantly claimed. The same depolymerization conditions are used (Claim 16). Since the same materials and procedure is being performed, it stands to reason the claimed content of derivative impurity and b* characteristics in the obtained aromatic diol is necessarily present in the absence of evidence to the contrary. Therefore, the ‘854 claims anticipate the present claims. The remaining limitations claimed are found within the ‘854 claims.
This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to STEPHEN E RIETH whose telephone number is (571)272-6274. The examiner can normally be reached Monday - Friday, 8AM-4PM Mountain Standard Time.
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, Curtis Mayes can be reached at (571)272-1234. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/STEPHEN E RIETH/Primary Examiner, Art Unit 1759
Prosecution Insights