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 .
Response to Amendment
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Any rejections and/or objections made in the previous Office action and not repeated below are hereby withdrawn.
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).
Claim Rejections - 35 USC § 103
Claim(s) 1-4, 6, 7, and 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chen (J. Appl. Poly. Sci.) in view of Tamada (US 2005/0096482 A1), Parrott (US 2018/0319950 A1), and Honda (JP2010-242016A). 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, 2, and 6, Chen teaches methods of depolymerizing poly(ethylene terephthalate) under microwave irradiation (Abstract) comprising adding PET particles to ethylene glycol (polyol) and reacting/dissolving the PET with depolymerization catalyst under microwave conditions under an inert (nitrogen) atmosphere to obtain BHET depolymerization product (“Glycolysis Reaction” of Page 2810). The PET starting material is from consumed soft drink bottles (“Materials”), construed as waste PET. The reaction takes place in a round bottom flask / reflex condenser assembly with no indication of a sealed/pressurized vessel. It is therefore implied depolymerization occurs under normal pressure. Chen teaches temperatures such as 150 and 170 degrees C and timeframes spanning 10-35 minutes (Figure 5). Chen reports the temperature is controlled/maintained to within +/- 3 degrees C (“Glycolysis Reaction” of Page 2810), which overlaps the +/- 2 degrees C range claimed. It would have been obvious to one of ordinary skill in the art to use a range within the claimed range because a reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill the art and Chen suggests the claimed range. A person of ordinary skill would be motivated to use the claimed amount, based on the teachings of Chen. See MPEP 2123.
Chen teaches at the end of the reaction, BHET is purified/removed from the polyol solvent via filtration (“Glycolysis Reaction” of Page 2810). Chen teaches oligomers are removed, which are deemed to be by-products that are also removed. The BHET can be re-used/polymerized to create new polyesters (Page 2809, Right Column). Chen differs from the subject matter claimed in that 1) titanium catalyst is not used, 2) microwave absorbent is not described, and 3) a particular microwave protocol of re-creating polyester from BHET is not described.
With respect to catalyst, Chen teaches the use of zinc acetate as catalyst (“Glycolysis Reaction” of Page 2810). Tamada also describes processes involving depolymerizing waste PET and producing new polyesters therefrom using microwaves (Abstract; Examples 7 and 8). Tamada teaches several catalysts are known for depolymerization, inclusive of titanium alkoxides such as tetrabutoxytitanate (TBT), tetraisopropoxytitanate (TPT) and tetraethoxytitanate; and zinc organic acid salts such as zinc acetate (¶ 24). In view of such, it would have been obvious to one of ordinary skill in the art to substitute zinc acetate with titanium alkoxides such as tetrabutoxytitanate (TBT), tetraisopropoxytitanate (TPT) and tetraethoxytitanate, and thereby predictably afford workable methods of depolymerizing polyesters as taught by Tamada. TBT is synonymous with butyl titanate. Alternatively, since the titanium alkoxides are heated in glycol solvent under ester exchange conditions, the in-situ formation of titanium glycolate would naturally arise.
With respect to microwave absorbent, Parrott also pertains to methods of depolymerizing polyesters with microwaves (Abstract) and notes the further inclusion of microwave absorber facilitates the reactions with more energy efficiency (¶ 20). It would have been obvious to one of ordinary skill in the art to utilize the microwave absorbers of Parrott within the systems of Chen because doing so would increase energy efficiency as taught by Parrott.
With respect to further esterification steps S3 and S4, Honda teaches it was known in the art polyester condensation can also be performed using microwave chemistry (Abstract; Claims). The use of microwaves provides energy-savings due to shortened reaction times (¶ 12). It would have been obvious to one of ordinary skill in the art to re-polymerize the recovered monomers of Chen with the methods of Honda because doing so would facilitate the creation of new polyester products in an energy-efficient manner as taught by Honda.
Honda teaches embodiments where terephthalic acid, ethylene glycol (“chain extender”), and bis(hydroxyethyl)terephthalate (BHET; same monomer produced by Chen) are reacted under microwave conditions to produce an esterification product, which is subsequently mixed with catalyst and phosphorus-containing stabilizer and condensation polymerized under vacuum conditions to yield polyester (¶ 64-65). Honda teaches the protocol can be used to create copolymers with further aliphatic diacids such as adipic acid (¶ 17), construed as aliphatic binary acid with 6 carbons. One or more polyol components, such as ethylene glycol and trimethylolpropane (“polyol”), can be used (¶ 18). A catalyst can also be used in the microwave reaction (¶ 25).
With respect to the inert atmosphere within Honda, although Honda does not explicitly recite the presence of an inert atmosphere, Parrott also pertains to methods involving chemical reactions with microwaves (Abstract) and notes it was known in the art such reactions can be performed at atmospheric or elevated pressure, either under air or in an inert atmosphere (¶ 13). It view of such, it would have been obvious to one of ordinary skill in the art to substitute the air atmosphere of the prior art with nitrogen, and thereby predictably afford the workable depolymerization/repolymerization of polyesters in accordance with the teachings of Parrott.
Regarding Claims 3 and 4, Chen teaches above 0 to 2 wt% of catalyst relative to weight of polyester (Figure 4) and instances where the PET:EG mass ratio is 1:(3-7) (Figure 3). The disclosed ranges overlap those claimed. It would have been obvious to one of ordinary skill in the art to use a range within the claimed range because a reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill the art and Chen suggests the claimed range. A person of ordinary skill would be motivated to use the claimed amount, based on the teachings of Chen. See MPEP 2123.
Regarding Claim 7, Parrott teaches microwave absorbers such as sodium chloride (¶ 20).
Regarding Claim 9, Honda teaches various organic phosphite stabilizers (¶ 34).
Claim(s) 5 and 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chen (J. Appl. Poly. Sci.) in view of Tamada (US 2005/0096482 A1), Parrott (US 2018/0319950 A1), Honda (JP2010-242016A), and Kappe (“Practical Microwave Synthesis for Organic Chemists”). As the cited JP publication is in a non-English language, a machine-translated version of the publication will be cited to.
The discussion regarding Chen, Tamada, Parrott, and Honda within ¶ 6-15 is incorporated herein by reference.
Regarding Claim 5, Chen teaches powers of 500-1000 W being used (Figure 2). While not indicating what frequency is used, Kappe teaches practically all commercial microwave instruments operate at 2.45 GHz so as to not to interfere with telecommunications equipment (Page 200). 2.45 GHz corresponds to a wavelength of roughly 122 mm. It would have been obvious to one of ordinary skill in the art to utilize a wavelength of 2.45 GHz / 122 mm because doing so would avoid interfering with telecommunications equipment as taught by Kappe.
Regarding Claim 10, Honda teaches microwave powers spanning 1-5 kW and times spanning 15-150 min (Table 1 and ¶ 22). While not specifically describing reactions using temperatures/times/powers within the specified ranges, it is known in the art that such are result effective variables subject to routine optimization with respect to microwave reactions (Sections 5.2.3 and 5.2.5 of Kappe). 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 or optimal reaction temperatures, timeframes, and microwave powers within the scope of the present claims so as to produce desired reaction characteristics.
Claim(s) 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chen (J. Appl. Poly. Sci.) in view of Tamada (US 2005/0096482 A1), Parrott (US 2018/0319950 A1), Honda (JP2010-242016A), and Ahmadnian (“Kinetic and Catalyst Studies of Polyethylene Terephthalate Synthesis”). As the cited JP publication is in a non-English language, a machine-translated version of the publication will be cited to.
The discussion regarding Chen, Tamada, Parrott, and Honda within ¶ 6-15 is incorporated herein by reference.
Regarding Claim 8, Honda teaches various catalysts can be used, such as titanium, aluminum, calcium, lithium, magnesium, cobalt, and manganese catalysts (¶ 25). To the extent Honda differs from the subject matter claimed by the use of particular titanium catalysts, Ahmadnian probed the use of various titanium catalysts in the polycondensation of polyesters from BHET (Section 2.2 and 2.4) and indicates titanium alkoxides such as titanium tetrabutoxide are known conventional catalysts useful for providing high catalytic activity (Sections 2.4.1 and 2.4.2). It would have been obvious to one of ordinary skill in the art to utilize known conventional catalysts such as titanium tetrabutoxide within the protocols of Honda, thereby predictably catalyzing the polycondensation reactions therein as taught by Ahmadnian.
Claim(s) 1-7, 9, and 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ikenaga (US 2009/0318579 A1) in view of Kappe (“Practical Microwave Synthesis for Organic Chemists”), Parrott (US 2018/0319950 A1), and Honda (JP2010-242016A). 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, 2, and 6, Ikenaga teaches methods of preparing recycled polyesters via depolymerizing polyester with microwaves to recover depolymerization product (Abstract; Examples). Ikenaga teaches examples where waste PET is added to ethylene glycol (polyol solvent) and titanium dioxide catalyst and reacted/dissolved with microwaves in an open container (i.e. normal pressure) for 30 minutes to obtain a depolymerization product (¶ 138, 41). Purification is performed via removing the polyol solvent by distillation to obtain BHET depolymerization monomer (¶ 138). Embodiments are taught where unreacted PET (deemed a by-product) is removed by purification (Table 2). Ikenaga differs from the subject matter claimed in that 1) depolymerization temperature / inert conditions / microwave absorbent are not described and 2) re-polymerization of recovered BHET to form new polyester is not described.
With respect to microwave depolymerization parameters, Kappe teaches general knowledge concepts regarding microwaves for use within organic synthesis. Kappe teaches microwave reaction temperatures are known to be critical toward successful reactions, desirable reaction timeframes, and yield (section 5.2.3 and 5.2.5) and thus, indicates the temperature of reacting to be a known result effective variable. 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 or optimal reaction temperatures within the scope of the present claims so as to produce desired reaction timeframes and yields.
With respect to temperature variance, Kappe teaches it was known in the art microwave instrumentation/software are capable of achieving/monitoring/maintaining reaction temperatures with excellent control (Section 5.2.4; e.g. Figure 5.5). Kappe teaches without maintaining a temperature program, the quality of reaction control is compromised, overheating may result, and reproducibility in results is diminished (Sections 5.1 and 5.2.4). It would have been obvious to one of ordinary skill in the art to utilize temperature control software, such that the temperature fluctuations are 2 degrees C or less, because doing so would maintain reaction control, prevent overheating, and increase reproducibility as taught by Kappe.
With respect to further esterification steps S3 and S4, Honda teaches it was known in the art polyester condensation can also be performed using microwave chemistry (Abstract; Claims). The use of microwaves provides energy-savings due to shortened reaction times (¶ 12). It would have been obvious to one of ordinary skill in the art to re-polymerize the recovered monomers of Ikenaga with the methods of Honda because doing so would facilitate the creation of new polyester products in an energy-efficient manner as taught by Honda.
Honda teaches embodiments where terephthalic acid, ethylene glycol (“chain extender”), and bis(hydroxyethyl)terephthalate (BHET; same monomer produced by Ikenaga) are reacted under microwave conditions to produce an esterification product, which is subsequently mixed with catalyst and phosphorus-containing stabilizer and condensation polymerized under vacuum conditions to yield polyester (¶ 64-65). Honda teaches the protocol can be used to create copolymers with further aliphatic diacids such as adipic acid (¶ 17), construed as aliphatic binary acid with 6 carbons. One or more polyol components, such as ethylene glycol and trimethylolpropane (“polyol”), can be used (¶ 18). A catalyst can also be used in the microwave reaction (¶ 25).
With respect to microwave absorbent, Parrott also pertains to methods of depolymerizing polyesters with microwaves (Abstract) and notes the further inclusion of microwave absorber facilitates the reactions with more energy efficiency (¶ 20). It would have been obvious to one of ordinary skill in the art to utilize the microwave absorbers of Parrott within the systems of Ikenaga because doing so would increase energy efficiency as taught by Parrott.
With respect to inert atmospheres, although Ikenaga/Honda do not utilize an inert atmosphere, Parrott also pertains to methods involving chemical reactions with microwaves (Abstract) and notes it was known in the art such reactions can be performed at atmospheric or elevated pressure, either under air or in an inert atmosphere (¶ 13). It view of such, it would have been obvious to one of ordinary skill in the art to substitute the air atmosphere of the prior art with nitrogen, and thereby predictably afford the workable depolymerization/repolymerization of polyesters in accordance with the teachings of Parrott.
Regarding Claims 3 and 4, Ikenaga teaches catalyst is used in amounts spanning 0.1-20 pbw relative to 100 pbw polyester (¶ 96), equivalent to 0.1-20 wt%. The weight ratio between polyester and reaction polyol is 1: (1-50) (¶ 103). The disclosed ranges overlap the ranges claimed. It would have been obvious to one of ordinary skill in the art to use a range within the claimed range because a reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill the art and Ikenaga suggests the claimed range. A person of ordinary skill would be motivated to use the claimed amount, based on the teachings of Ikenaga. See MPEP 2123.
Regarding Claim 5, Ikenaga uses a reactor emitting a 2.45 GHz microwave frequency at a power ranging from 0-700 W (¶ 136). 2.45 GHz corresponds to a wavelength of roughly 122 mm. The disclosed power range overlaps that claimed. It would have been obvious to one of ordinary skill in the art to use a range within the claimed range because a reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill the art and Ikenaga suggests the claimed range. A person of ordinary skill would be motivated to use the claimed amount, based on the teachings of Ikenaga. See MPEP 2123.
Regarding Claim 7, Parrott teaches microwave absorbers such as sodium chloride (¶ 20).
Regarding Claim 9, Honda teaches various organic phosphite stabilizers (¶ 34).
Regarding Claim 10, Honda teaches microwave powers spanning 1-5 kW and times spanning 15-150 min (Table 1 and ¶ 22). While not specifically describing reactions using temperatures/times/powers within the specified ranges, it is known in the art that such are result effective variables subject to routine optimization with respect to microwave reactions (Sections 5.2.3 and 5.2.5 of Kappe). 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 or optimal reaction temperatures, timeframes, and microwave powers within the scope of the present claims so as to produce desired reaction characteristics.
Claim(s) 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ikenaga (US 2009/0318579 A1) in view of Kappe (“Practical Microwave Synthesis for Organic Chemists”), Parrott (US 2018/0319950 A1), Honda (JP2010-242016A), and Ahmadnian (“Kinetic and Catalyst Studies of Polyethylene Terephthalate Synthesis”). As the cited JP publication is in a non-English language, a machine-translated version of the publication will be cited to.
The discussion regarding Ikenaga, Kappe, and Honda within ¶ 24-35 is incorporated herein by reference.
Regarding Claim 8, Honda teaches various catalysts can be used, such as titanium, aluminum, calcium, lithium, magnesium, cobalt, and manganese catalysts (¶ 25). To the extent Honda differs from the subject matter claimed by the use of particular titanium catalysts, Ahmadnian probed the use of various titanium catalysts in the polycondensation of polyesters from BHET (Section 2.2 and 2.4) and indicates titanium alkoxides such as titanium tetrabutoxide are known conventional catalysts useful for providing high catalytic activity (Sections 2.4.1 and 2.4.2). It would have been obvious to one of ordinary skill in the art to utilize known conventional catalysts such as titanium tetrabutoxide within the protocols of Honda, thereby predictably catalyzing the polycondensation reactions therein as taught by Ahmadnian.
Response to Arguments
Applicant's arguments filed 5/7/2026 have been fully considered but they are not persuasive.
Applicant generally argues Chen/Ikenaga fail to describe co-esterification and do not realize close-loop recycling. This is not found persuasive as the combination of references meets all limitations claimed.
Applicant generally argues Honda describes terephthalic acid, which is not an aliphatic acid. This is not found persuasive as Honda teaches aliphatic diacids can be used to create co-polyesters.
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.
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/STEPHEN E RIETH/Primary Examiner, Art Unit 1759
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