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 .
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1, 4, 5, and 7-10 is/are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Reinsberg (US 2025/0215187 A1).
Regarding Claims 1, 4, and 5, Reinsberg teaches methods of depolymerizing polyethylene terephthalate polyester comprising generating glycolate anions (alkoxy anions) from ethylene glycol (alcohol) via current through a cathode in electrolysis and reacting the resulting glycolate anions with polyester to form monomers (Abstract; ¶ 345-357).
Regarding Claim 7, Reinsberg teaches terephthalic acid is produced (¶ 357).
Regarding Claim 8, Reinsberg teaches the use of waste PET (¶ 305).
Regarding Claims 9 and 10, Reinsberg teaches the output comprises BHET and TPA monomers (¶ 357) whereby BHET is isolated via filtration / crystallization (¶ 338). Such a process broadly reads on the claim since TPA monomer is isolated via passing through a filter in the presence of organic solvent (glycol) in which the TPA monomers are soluble.
Claim(s) 1-5 and 7-9 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Kamata (JP2004-250544A). As the cited JP publication is in a non-English language, a machine-translated version of the publication will be cited to.
Regarding Claims 1, 4, and 5, Kamata teaches methods of depolymerizing polyethylene terephthalate polyester comprising generating hydroxide anions from a catholyte containing ethylene glycol (alcohol) and small amounts of water via current through a cathode in electrolysis and reacting the resulting basic mixture with polyester to form monomers (Abstract; Examples). While Kamata does not explicitly state alkoxide anions are generated/present/reacted with PET, Kamata clearly indicates electrolysis reaction generates hydroxide anions diluted in excess alcohol. Since hydroxide / alkoxide are in equilibrium with one another in such mixtures, the process of Kamata is seen to necessarily entail to production of alkoxide anions from the alcohol during electrolysis and small quantities of alkoxide taking part in the reaction with polyesters in the absence of evidence to the contrary.
Regarding Claims 2 and 3, Kamata teaches other alcohols can be used such as methanol (¶ 6).
Regarding Claim 7, Kamata teaches depolymerizing PET to form terephthalic acid (Abstract; Examples).
Regarding Claim 8, Kamata teaches waste PET materials (¶ 1).
Regarding Claim 9, Kamata teaches isolating the monomers from the alcohol via precipitation/filtration (¶ 10).
Claim(s) 11-19 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Luca (US 2022/0170167 A1).
Regarding Claims 11, 12, 18, and 19, Luca teaches electrochemical devices comprising cathode and an anode in physical contact with the cathode and a separator separating the catholyte and anolyte permeable for cations or anions, the catholyte in physical contact with cathode and anolyte in physical contact with anode (¶ 34, 47, 93-94). Luca teaches catholyte comprising methanol (alcohol) and polyethylene terephthalate polyester disposed therein (Table 3; ¶ 78-79).
Regarding Claims 13 and 14, Luca teaches embodiments where methoxy anions are present (Scheme 1 of ¶ 78).
Regarding Claim 15, Luca teaches embodiments where anolyte can be water/alcohol mixture (¶ 93).
Regarding Claim 16, Luca teaches power source in electrical communication with cathode (¶ 14).
Regarding Claim 17, Luca teaches various polymeric cation selective membranes (¶ 47), construed as polymer-based cation exchange membranes.
Claim Rejections - 35 USC § 102/103
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
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.
Claim(s) 1-5 and 7-9 is/are rejected under 35 U.S.C. 102(a)(1) as anticipated by or, in the alternative, under 35 U.S.C. 103 as obvious over Luca (US 2022/0170167 A1).
Regarding Claims 1-5, Luca teaches methods of depolymerizing polyesters such as polyethylene terephthalate into monomers via passing a current through a cathode to form methoxide / hydroxide ions (Table 3; ¶ 78-79). As Luca teaches the presence of methoxide anions and methoxide anions are reactive toward polyesters for depolymerization, the reactive mixtures are seen to necessarily entail the reaction of alkoxides with the polyesters over the course of forming monomers. Therefore, Luca anticipates the claim.
Alternatively, Luca indicates only alcohol is required, whereby water is present in “some embodiments” (¶ 36-39; Claims 1 and 4), thus suggesting embodiments where only alkoxide would be generated and thus, only alkoxide would participate in depolymerization. It would have been obvious to one of ordinary skill in the art to substitute alcohol/water mixtures with alcohol solvent, thereby predictably affording the depolymerization of polyesters via electrolysis in accordance with the teachings of Luca.
Regarding Claim 7, Luca teaches the formation of terephthalic acid (Table 3).
Regarding Claim 8, Luca teaches polyester waste material (¶ 114).
Regarding Claim 9, Luca teaches isolating monomers from the alcohol (see for instance ¶ 107).
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.
Claim(s) 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Luca (US 2022/0170167 A1).
Regarding Claim 6, Luca teaches methods of depolymerizing polyesters such as polyethylene terephthalate into monomers via passing a current through a cathode to form methoxide / hydroxide ions (Table 3; ¶ 78-79). Luca describes embodiments where only alcohol is required, whereby water is present in “some embodiments” (¶ 36-39; Claims 1 and 4), thus suggesting embodiments where only alkoxide would be generated and thus, only alkoxide would participate in depolymerization. It would have been obvious to one of ordinary skill in the art to substitute alcohol/water mixtures with alcohol solvent, thereby predictably affording the depolymerization of polyesters via electrolysis in accordance with the teachings of Luca. The use of methanol as solvent within the depolymerization mixtures of Luca is seen to intrinsically result in formation of dimethyl terephthalate.
Claim(s) 9 and 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Luca (US 2022/0170167 A1) in view of Robinson (GB 784248A).
The discussion regarding Luca within ¶ 32 is incorporated herein by reference.
Regarding Claims 9 and 10, Luca differs from the subject matter claimed in that particular purification methods for dimethyl terephthalate are not described. Robinson is also directed toward the formation dimethyl terephthalate from methanol / waste polyester mixtures (Page 1). Robinson teaches a purification protocol whereby dimethyl terephthalate solids are filtered, dissolved in xylene, the resulting solution filtered to remove unreacted polyester, and then cooled for crystallization (Example 1). It would have been obvious to one of ordinary skill in the art to utilize the purification protocol of Robinson within the protocols of Luca because doing so would achieve removal of residual polyester and purification of dimethyl terephthalate into pure crystals as taught by Robinson.
Allowable Subject Matter
Claim 20 is allowed.
Related Art
Nishiyama (JPS53-012806A) describes the synthesis of dimethyl carbamates via electrolysis. The synthesis of carbmamates from polyurethanes is not described.
Bulan (US 2022/0227701 A1) describes methods of recycling polyurethanes via depolymerizing polyurethanes and subsequently subjecting the resulting carbon dioxide to electrolysis.
Shi (CN 113897628A) and Luca (WO 2024/238960 A1) both describe further methods concerning depolymerizing polyesters via electrolysis.
Conclusion
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/STEPHEN E RIETH/Primary Examiner, Art Unit 1759