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 .
Priority
Applicant’s claim for the benefit of a prior-filed application under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged.
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
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.
Claims 1 and 3-15 are rejected under 35 U.S.C. 103 as being unpatentable over Penu et al. (US 2016/0311971 A1) in view of Cui et al. (CN 108239262 A, machine translation in English used for citation), Coszach et al. (US 2016/0068505 A1), Kakizawa et al. (JP H10-127751 A, machine translation in English used for citation), Suzuki et al. (US 2010/0004404 A1), Wadrop (WO 2015/092425 A1), and Bloom et al. (US 2009/0018300 A1).
Regarding claim 1, Penu teaches an integrated process for the production of polylactide (PLA) comprising the steps of [0015] water evaporation from the lactic acid aqueous solution starting stream [0016], and oligomerization of lactic acid and recycle of reaction water and unconverted lactic acid [0017], which reads on a method of valorizing a flux containing undesired lactic acid in the production process of polylactic acid, said process comprising the steps of: i. oligomerization of a substantially pure lactic acid feed. Penu teaches that the process further comprises the steps of [0015] cyclization of the lactic acid oligomers and production of crude lactide and recycle of unreacted monomers, catalytic residues, and heavy products [0018], and purification of the crude lactide and recycle of lactic acid, water, heavy components, catalytic residues, and impurities [0019], wherein recycle of the cyclization step is sent to a trans-esterification reactor [0023], wherein recycle of the purification step comprising the light components, is sent to a reactor, the other part to a hydrolysis reactor, and the heavy components stream is sent to a trans-esterification reactor [0024], where from the cyclization step, and besides the obtained crude lactide stream which will be sent to the purification, it is necessary to recover the unreacted oligomers, the non volatile impurities, the high boiling point lactic acid oligomer, the low molecular weight polylactic acid, as well as the heavy residues, and the catalytic residues which all form the cyclization residues [0030], wherein the cyclization residues are sent back to the oligomerization step, where a purge is absolutely needed to avoid dramatic accumulation of catalytic residues in the system as well as degradation by-products, and which also contribute to the elimination of impurities, wherein the products of the purge are then sent to the trans-esterification reactor [0031], wherein during the purification step, it is recovered a light components stream containing lactic acid and water which is divided into two sub-streams, wherein the first of the light components stream is sent to the hydrolysis reactor while the second of the light components stream is recycled to the reactor, while a bottom stream containing heavy oligomers, lactide, and impurities constituting stream will be recycled to the trans-esterification reactor [0032], which reads on said process comprising the steps of: ii. cyclization of the lactic acid oligomers to obtain lactides and a first residual stream, wherein the first residual stream comprises unreacted oligomers, impurities, and catalytic residues transferred, at least partially, to a transesterification and a hydrolysis step, and iii. purification of the lactides to obtain purified lactides, a second, and a third residual stream, wherein the purified lactides comprise lactide, and wherein the second residual stream comprises unreacted lactic acid, and oligomers transferred, at least partially, to the oligomerization step, and wherein the third residual stream comprises unreacted lactic acid, oligomers, impurities, and residual lactide transferred, at least partially, to a transesterification and hydrolysis step. Penu teaches that the process further comprises the step of [0015] ring opening polymerization of the purified lactide and production of PLA [0020], which reads on said process comprising the steps of: iv. polymerization by ring opening of the purified lactides to obtain polylactic acid. Penu teaches that the process further comprises the step of [0015] purification of the PLA by devolatilization and recycle of non-reacted lactide [0021], wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor [0025], wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers an diluents as well as impurities [0034], where in the trans-esterification reactor, a trans-esterification reaction shall take place [0037], wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer [0038], which reads on said process comprising the steps of: v. purification of the polylactic acid to obtain purified polylactic acid comprising substantially polylactic acid and unreacted lactide, and impurities transferred, at least partially, to the lactide purification step, and vi. Transesterification and hydrolysis of the at least partially transferred first and third residual streams to obtain a fourth residual stream, wherein the fourth residual stream comprises undesired lactic acid.
Penu does not teach that the step of i. oligomerization of a substantially pure lactic acid feed is i. oligomerization of a substantially pure L-lactic acid feed. However, Cui teaches a process for producing oligomeric L-lactic acid including the following steps: [0009] preparing the raw material that is a 40-60 wt% L-lactic acid solution with an optical purity of L-lactic acid greater than or equal to 99.5% [0010], and dehydrating and oligomerizing to obtain L-lactic acid oligomers [0011]. Penu and Cui are analogous art because both references are in the same field of endeavor of a method comprising oligomerization of a lactic acid feed. Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use 40-60 wt% L-lactic acid solution with an optical purity of L-lactic acid greater than or equal to 99.5% to substitute for Penu’s lactic acid aqueous solution starting stream in Penu’s steps of water evaporation from the lactic acid aqueous solution starting stream, and oligomerization of lactic acid and recycle of reaction water and unconverted lactic acid, as suggested by Cui. The proposed modification would read on the step of i. oligomerization of a substantially pure lactic acid feed is i. oligomerization of a substantially pure L-lactic acid feed as claimed. One of ordinary skill in the art would have been motivated to do so because Cu teaches that preparing the raw material that is a 40-60 wt% L-lactic acid solution with an optical purity of L-lactic acid greater than or equal to 99.5% [0010], and dehydrating and oligomerizing to obtain L-lactic acid oligomers [0011] is beneficial for producing oligomeric L-lactic acid [0009], which would have been beneficial for Penu’s process producing oligomeric L-lactic acid, which would have been desirable for Penu’s process because Penu teaches that the integrated process for the production of polylactide (PLA) comprises the steps of [0015] water evaporation from the lactic acid aqueous solution starting stream [0016], and oligomerization of lactic acid and recycle of reaction water and unconverted lactic acid [0017].
Penu does not teach that the purified lactides comprise L-lactide and meso-lactide. However, Coszach teaches a purified stream containing L-lactide and meso-lactide that is obtained [0030] in a process for the recovery and production of meso-lactide from a crude lactide containing stream [0021]. Penu and Coszach are analogous art because both references are in the same field of endeavor of a method comprising purification of lactides. Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use L-lactide and meso-lactide to substitute for Penu’s purified crude lactide in Penu’s steps of purification of the crude lactide, and ring opening polymerization of the purified lactide, as suggested by Coszach. The proposed modification would read on the purified lactides comprise L-lactide and meso-lactide as claimed. One of ordinary skill in the art would have been motivated to do so because Coszach taches that that obtaining a purified stream containing L-lactide and meso-lactide [0030] is beneficial for recovery of meso-lactide from a crude lactide containing stream [0021] and for obtaining L-lactide [0030], which would have been beneficial for obtaining pure L-lactide and meso-lactide from Penu’s crude lactide and for improving an ability of carrying out Penu’s step of ring opening polymerization of the purified lactide and production of PLA, which would have been desirable for Penu’s process because Penu teaches that the process further comprises the steps of [0015] purification of the crude lactide [0019], and ring opening polymerization of the purified lactide and production of PLA [0020].
Penu does not teach that the residual lactide in the third residual stream comprises residual L-lactide, D-lactide, and meso-lactide. However, Kakizawa teaches that lactide is transesterified in the presence of a ring-opening polymerization catalyst [0020], that lactide has isomers: L-lactide, D-lactide, and meso-lactide [0023], and that lactic acid-based polyesters can achieve desirable polymer properties by combining these three types of lactide [0023]. Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use L-lactide, D-lactide, and meso-lactide to substitute for Penu’s lactide in Penu’s bottom stream containing heavy oligomers, lactide, and impurities constituting stream in Penu’s process, as suggested by Kakizawa. The proposed modification would read on the residual lactide in the third residual stream comprises residual L-lactide, D-lactide, and meso-lactide as claimed. One of ordinary skill in the art would have been motivated to do so because Kakizawa teaches that the lactide isomers that are L-lactide, D-lactide, and meso-lactide [0023] are beneficial for transesterifying them in the presence of a ring-opening polymerization catalyst [0020], and that combining these three types of lactide to obtain lactic acid-based polyesters is beneficial for achieving desirable polymer properties [0023], which would have been desirable for Penu’s lactide in Penu’s bottom stream containing heavy oligomers, lactide, and impurities constituting stream in Penu’s process because Penu teaches that the process further comprises the step of [0015] purification of the crude lactide and recycle of lactic acid, water, heavy components, catalytic residues, and impurities [0019], wherein recycle of the purification step comprising the light components, is sent to a reactor, the other part to a hydrolysis reactor, and the heavy components stream is sent to a trans-esterification reactor [0024], where from the cyclization step, and besides the obtained crude lactide stream which will be sent to the purification, it is necessary to recover the unreacted oligomers, the non volatile impurities, the high boiling point lactic acid oligomer, the low molecular weight polylactic acid, as well as the heavy residues, and the catalytic residues which all form the cyclization residues [0030], wherein during the purification step, it is recovered a light components stream containing lactic acid and water which is divided into two sub-streams, wherein the first of the light components stream is sent to the hydrolysis reactor while the second of the light components stream is recycled to the reactor, while a bottom stream containing heavy oligomers, lactide, and impurities constituting stream will be recycled to the trans-esterification reactor [0032].
Penu does not teach that the polylactic acid in the purified polylactic acid is substantially L-polylactic acid. However, Suzuki teaches purified polylactic acid that is PLLA [0069] obtained by polymerization of L-lactide with an optical purity of 99% or more [0067] and removing excess lactide so as to obtain a purified polylactic acid [0068]. Penu and Suzuki are analogous art because both references are in the same field of endeavor of a method comprising polymerization by ring opening of a purified lactide and purification of the polylactic acid. Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use polylactic acid that PLLA that is poly L-lactic acid to substitute for Penu’s PLA in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, as suggested by Suzuki. The proposed modification would read on the polylactic acid in the purified polylactic acid is substantially L-polylactic acid as claimed. One of ordinary skill in the art would have been motivated to do so because Suzuki teaches purified polylactic acid that is PLLA [0069] obtained by polymerization of L-lactide with an optical purity of 99% or more [0067] and removing excess lactide so as to obtain a purified polylactic acid [0068], which means that the proposed modification would have been beneficial for purifying PLLA that is poly L-lactic acid in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, which would have been desirable for Penu’s process because Penu teaches that the process further comprises the step of [0015] purification of the PLA by devolatilization and recycle of non-reacted lactide [0021].
Penu does not teach that the unreacted lactide in the purified polylactic acid is unreacted L-lactide, and unreacted meso-lactide. However, Coszach teaches a crude lactide-containing stream that results from devolatilization of PLA [0034], wherein the crude lactide stream comprises meso-lactide and L-lactide [0036]. Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use L-lactide and meso-lactide to substitute for Penu’s non-reacted lactide in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, as suggested by Coszach. One of ordinary skill in the art would have been motivated to do so because Coszach teaches that the meso-lactide and L-lactide are present in a crude lactide stream [0036] that is beneficial for resulting from devolatilization of PLA [0034], which means that the proposed modification would have been beneficial for obtaining L-lactide and meso-lactide from Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, which would have been desirable for Penu’s process because Penu teaches that the process further comprises the step of [0015] purification of the PLA by devolatilization and recycle of non-reacted lactide [0021].
Penu does not teach that transesterification and hydrolysis of the at least partially transferred first and third residual streams obtains a fourth and a fifth residual stream, wherein the fourth residual stream comprises undesired D-lactic acid and wherein the fifth residual stream comprises one or more undesired D-lactic acid esters. However, Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9). Penu and Wadrop are analogous are because both references are in the same field of endeavor of a method comprising hydrolysis and obtaining lactic acid. Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use D-lactic acid and an ester of D-lactic acid to substitute for Penu’s unreacted monomers in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers an diluents as well as impurities, wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor, where in the trans-esterification reactor, a trans-esterification reaction shall take place, wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer, such that the D-lactic acid and the ester of D-lactic acid are placed in separate streams, as suggested by Wadrop. The proposed modification would read on transesterification and hydrolysis of the at least partially transferred first and third residual streams obtains a fourth and a fifth residual stream, wherein the fourth residual stream comprises undesired D-lactic acid and wherein the fifth residual stream comprises one or more undesired D-lactic acid esters as claimed. One of ordinary skill in the art would have been motivated to do so because it would have been beneficial for separating D-lactic acid and an ester of D-lactic acid from Penu’s PLA because Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9), and because Penu teaches that the process further comprises the step of [0015] purification of the PLA by devolatilization and recycle of non-reacted lactide [0021], wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor [0025], wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers an diluents as well as impurities [0034], where in the trans-esterification reactor, a trans-esterification reaction shall take place [0037], wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer [0038].
Penu does not teach that the lactic acid of the fourth residual stream and the one or more lactic acid esters of the fifth residual stream are used, at least partially, as a base for the synthesis of molecules insensitive to the optical isometry D or L of lactic acid and/or lactic acid ester(s). However, Bloom teaches that biobased acrylic acid or acrylate esters may be synthesized from biobased lactic acid or lactate esters [0041]. Penu and Bloom are analogous art because both references are in the same field of endeavor of a method using lactic acid. Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use a step of synthesizing biobased acrylic acid or acrylate esters from lactic acid and lactate esters that are the unreacted monomers in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers an diluents as well as impurities, wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor, where in the trans-esterification reactor, a trans-esterification reaction shall take place, wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer, as suggested by Bloom. The proposed modification would read on the lactic acid of the fourth residual stream and the one or more lactic acid esters of the fifth residual stream are used, at least partially, as a base for the synthesis of molecules insensitive to the optical isometry D or L of lactic acid and/or lactic acid ester(s) as claimed. One of ordinary skill in the art would have been motivated to do so because Bloom teaches that biobased acrylic acid or acrylate esters may be synthesized from biobased lactic acid or lactate esters [0041], which would have been beneficial for providing a utility for lactic acid and lactate esters that are the unreacted monomers in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, which would have been desirable for Penu’s process because Penu teaches that the process further comprises the step of [0015] purification of the PLA by devolatilization and recycle of non-reacted lactide [0021], wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor [0025], wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers an diluents as well as impurities [0034], where in the trans-esterification reactor, a trans-esterification reaction shall take place [0037], wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer [0038].
Penu does not teach that the method of valorizing a flux containing undesired lactic acid is a method of valorizing a flux containing undesired D-lactic acid and/or one or more undesired D-lactic acid esters in the production process of L-polylactic acid. Based on the modifications that are proposed above, Penu in view of Cui, Coszach, Kakizawa, Suzuki, Wadrop and Bloom renders it obvious that the method of valorizing a flux containing undesired lactic acid is a method of valorizing a flux containing undesired D-lactic acid and/or one or more undesired D-lactic acid esters in the production process of L-polylactic acid.
Regarding claim 3, since Penu does not teach D,L-polylactic acid, and since Penu’s process would not inherently comprise D,L-polylactic acid, Penu’s teachings read on wherein the purified polylactic acid comprises 0% by weight of D,L-polylactic acid based on the total weight of the purified polylactic acid, which reads on the claimed range.
Regarding claim 4, Penu teaches that the process further comprises the step of [0015] purification of the crude lactide and recycle of lactic acid, water, heavy components, catalytic residues, and impurities [0019], wherein recycle of the cyclization step is sent to a trans-esterification reactor [0023], wherein recycle of the purification step comprising the light components, is sent to a reactor, the other part to a hydrolysis reactor, and the heavy components stream is sent to a trans-esterification reactor [0024], wherein during the purification step, it is recovered a light components stream containing lactic acid and water which is divided into two sub-streams, wherein the first of the light components stream is sent to the hydrolysis reactor while the second of the light components stream is recycled to the reactor, while a bottom stream containing heavy oligomers, lactide, and impurities constituting stream will be recycled to the trans-esterification reactor [0032], wherein the trans-esterification reaction may be operated in accordance with known processes and under usual conditions, wherein such a reaction may be achieved in one or more than one reactors at a temperature comprised between 80 and 200° C and at a pressure comprised between the atmospheric pressure and 10-50 bar and in the presence of a catalyst [0039], wherein with the purification step, to achieve a separation, the mixture coming out of the trans-esterification reactor is sent to a distillation step operated under pressure of 0.01 to 4 bar and at a temperature comprised between 40 to 180° C [0043], wherein the crude lactide stream resulting from cyclization is sent to purification of lactide, which is represented by reactors comprising any well known apparatus used for such purification and comprising melt crystallization means [0053], which reads on wherein the lactide purification step comprises one or more sub-steps including a pre-purification step, a melt purification step, and a separation step as claimed.
Regarding claim 5, the modifications that are proposed above for claim 1 render it obvious that part of the unreacted L-lactide, the unreacted meso-lactide, and the impurities are transferred to the transesterification and the hydrolysis step as claimed.
Regarding claim 6, the modifications that are proposed above for claim 1 render it obvious that part of the second residual stream is transferred to the transesterification and/or the hydrolysis step as claimed.
Regarding claim 7, Penu teaches that before being sent to the hydrolysis reaction, the crude alkyl lactate exiting the trans-esterification reactor is first purified in order to separate the lactate molecules from the heavier molecules [0043], that with this purification step, to achieve separation, the mixture coming out of the trans-esterification reactor is first sent to a distillation step [0043], and that the hydrolysis reactor is receiving, after distillation, the stream from the trans-esterification reactor [0044], which reads on the method according to claim 1, further comprising a distillation step between the transesterification step and the hydrolysis step as claimed.
Regarding claim 8, the modifications that are proposed above for claims 1 and 7 render it obvious wherein the fifth residual stream is obtained at the distillation step as claimed.
Regarding claim 9, the modifications that are proposed above for claim 1 renders it obvious wherein the fourth residual stream is obtained at the hydrolysis step as claimed.
Regarding claim 10, Penu does not teach that the fourth residual stream comprises between 2% and 50% by weight of D-lactic acid based on the total weight of the fourth residual stream. However, Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9). Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use D-lactic acid and an ester of D-lactic acid to substitute for Penu’s unreacted monomers in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers as diluents as well as impurities, wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor, where in the trans-esterification reactor, a trans-esterification reaction shall take place, wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer, such that the D-lactic acid and the ester of D-lactic acid are placed in separate streams, and to select the amount of D-lactic acid to be between 2% and 50% by weight of D-lactic acid based on the total weight of Penu’s unreacted monomers as diluents as well as impurities. The proposed modification would read on wherein the fourth residual stream comprises between 2% and 50% by weight of D-lactic acid based on the total weight of the fourth residual stream as claimed. One of ordinary skill in the art would have been motivated to do so because it would have been beneficial for separating D-lactic acid and an ester of D-lactic acid from Penu’s PLA because Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9), and because Penu teaches that the process further comprises the step of [0015] purification of the PLA by devolatilization and recycle of non-reacted lactide [0021], wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor [0025], wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers an diluents as well as impurities [0034], where in the trans-esterification reactor, a trans-esterification reaction shall take place [0037], wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer [0038].
Regarding claim 11, Penu does not teach that the fourth residual stream comprises between 5% and 30% by weight of D-lactic acid based on the total weight of the fourth residual stream. However, Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9). Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use D-lactic acid and an ester of D-lactic acid to substitute for Penu’s unreacted monomers in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers as diluents as well as impurities, wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor, where in the trans-esterification reactor, a trans-esterification reaction shall take place, wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer, such that the D-lactic acid and the ester of D-lactic acid are placed in separate streams, and to select the amount of D-lactic acid to be between 5% and 30% by weight of D-lactic acid based on the total weight of Penu’s unreacted monomers as diluents as well as impurities. The proposed modification would read on wherein the fourth residual stream comprises between 5% and 30% by weight of D-lactic acid based on the total weight of the fourth residual stream as claimed. One of ordinary skill in the art would have been motivated to do so because it would have been beneficial for separating D-lactic acid and an ester of D-lactic acid from Penu’s PLA because Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9), and because Penu teaches that the process further comprises the step of [0015] purification of the PLA by devolatilization and recycle of non-reacted lactide [0021], wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor [0025], wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers an diluents as well as impurities [0034], where in the trans-esterification reactor, a trans-esterification reaction shall take place [0037], wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer [0038].
Regarding claim 12, Penu does not teach that the fourth residual stream comprises between 10% and 20% by weight of D-lactic acid based on the total weight of the fourth residual stream. However, Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9). Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use D-lactic acid and an ester of D-lactic acid to substitute for Penu’s unreacted monomers in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers as diluents as well as impurities, wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor, where in the trans-esterification reactor, a trans-esterification reaction shall take place, wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer, such that the D-lactic acid and the ester of D-lactic acid are placed in separate streams, and to select the amount of D-lactic acid to be between 10% and 20% by weight of D-lactic acid based on the total weight of Penu’s unreacted monomers as diluents as well as impurities. The proposed modification would read on wherein the fourth residual stream comprises between 10% and 20% by weight of D-lactic acid based on the total weight of the fourth residual stream as claimed. One of ordinary skill in the art would have been motivated to do so because it would have been beneficial for separating D-lactic acid and an ester of D-lactic acid from Penu’s PLA because Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9), and because Penu teaches that the process further comprises the step of [0015] purification of the PLA by devolatilization and recycle of non-reacted lactide [0021], wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor [0025], wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers an diluents as well as impurities [0034], where in the trans-esterification reactor, a trans-esterification reaction shall take place [0037], wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer [0038].
Regarding claim 13, Penu does not teach that the fifth residual stream comprises between 2% and 50% by weight of D-lactic acid ester based on the total weight of the fifth residual stream. However, Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9). Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use D-lactic acid and an ester of D-lactic acid to substitute for Penu’s unreacted monomers in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers as diluents as well as impurities, wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor, where in the trans-esterification reactor, a trans-esterification reaction shall take place, wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer, such that the D-lactic acid and the ester of D-lactic acid are placed in separate streams, and to select the amount of an ester of D-lactic acid to be between 2% and 50% by weight of an ester of D-lactic acid based on the total weight of Penu’s unreacted monomers as diluents as well as impurities. The proposed modification would read on wherein the fifth residual stream comprises between 2% and 50% by weight of D-lactic acid ester based on the total weight of the fifth residual stream as claimed. One of ordinary skill in the art would have been motivated to do so because it would have been beneficial for separating D-lactic acid and an ester of D-lactic acid from Penu’s PLA because Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9), and because Penu teaches that the process further comprises the step of [0015] purification of the PLA by devolatilization and recycle of non-reacted lactide [0021], wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor [0025], wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers an diluents as well as impurities [0034], where in the trans-esterification reactor, a trans-esterification reaction shall take place [0037], wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer [0038].
Regarding claim 14, Penu does not teach that the fifth residual stream comprises between 10% and 40% by weight of D-lactic acid ester based on the total weight of the fifth residual stream. However, Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9). Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use D-lactic acid and an ester of D-lactic acid to substitute for Penu’s unreacted monomers in Penu’s step of purification of the PLA by devolatilization and recycle of non-reacted lactide, wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers as diluents as well as impurities, wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor, where in the trans-esterification reactor, a trans-esterification reaction shall take place, wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer, such that the D-lactic acid and the ester of D-lactic acid are placed in separate streams, and to select the amount of an ester of D-lactic acid to be between 10% and 40% by weight of an ester of D-lactic acid based on the total weight of Penu’s unreacted monomers as diluents as well as impurities. The proposed modification would read on wherein the fifth residual stream comprises between 10% and 40% by weight of D-lactic acid ester based on the total weight of the fifth residual stream as claimed. One of ordinary skill in the art would have been motivated to do so because it would have been beneficial for separating D-lactic acid and an ester of D-lactic acid from Penu’s PLA because Wadrop teaches hydrolyzing an ester of lactic acid to produce D-lactic acid (p. 21, l. 6, 8-9), and because Penu teaches that the process further comprises the step of [0015] purification of the PLA by devolatilization and recycle of non-reacted lactide [0021], wherein recycle of the purification step is sent partially to the purification step of the crude lactide, and the rest is sent to the trans-esterification reactor [0025], wherein the devolatilization step purifies the obtained PLA and recovers unreacted monomers an diluents as well as impurities [0034], where in the trans-esterification reactor, a trans-esterification reaction shall take place [0037], wherein the so formed alkyl lactate is sent to a hydrolysis step to recover the starting monomer [0038].
Regarding claim 15, the modifications that are proposed above for claim 1 renders it obvious wherein the molecules are selected from acrylic acid, and acrylic ester as claimed.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Penu et al. (US 2016/0311971 A1) in view of Cui et al. (CN 108239262 A, machine translation in English used for citation), Coszach et al. (US 2016/0068505 A1), Kakizawa et al. (JP H10-127751 A, machine translation in English used for citation), Suzuki et al. (US 2010/0004404 A1), Wadrop (WO 2015/092425 A1), and Bloom et al. (US 2009/0018300 A1) as applied to claim 1, and further in view of Sudo et al. (US 2014/0206807 A1).
Regarding claim 2, Penu in view of Cui, Coszach, Kakizawa, Suzuki, Wadrop, and Bloom renders obvious the method according to claim 1 as explained above.
Penu does not teach that the first residual stream substantially comprises D-lactic acid oligomers and/or D,L-lactic acid oligomers. However, Sudo teaches a linear oligomer of D-lactic acid that is present in a polylactic acid resin composition [0023]. Penu and Sudo are analogous art because both references are in the same field of endeavor of a method that involves lactic acid oligomers. Before the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to use a linear oligomer of D-lactic acid to substitute for Penu’s unreacted oligomers and/or Penu’s high boiling point lactic acid oligomer in Penu’s step of cyclization of the lactic acid oligomers and production of crude lactide and recycle of unreacted monomers, catalytic residues, and heavy products, wherein recycle of the cyclization step is sent to a trans-esterification reactor, wherein recycle of the purification step comprising the light components, is sent to a reactor, the other part to a hydrolysis reactor, and the heavy components stream is sent to a trans-esterification reactor, where from the cyclization step, and besides the obtained crude lactide stream which will be sent to the purification, it is necessary to recover the unreacted oligomers, the non volatile impurities, the high boiling point lactic acid oligomer, the low molecular weight polylactic acid, as well as the heavy residues, and the catalytic residues which all form the cyclization residues, wherein the cyclization residues are sent back to the oligomerization step, where a purge is absolutely needed to avoid dramatic accumulation of catalytic residues in the system as well as degradation by-products, and which also contribute to the elimination of impurities, wherein the products of the purge are then sent to the trans-esterification reactor, as suggested by Sudo. The proposed modification would read on the first residual stream substantially comprises D-lactic acid oligomers as claimed. One of ordinary skill in the art would have been motivated to do so because Sudo teaches that a linear oligomer of D-lactic acid is beneficial for being useful in a polylactic acid resin composition [0023], which means that the proposed modification would have been beneficial for obtaining a linear oligomer of D-lactic acid in Penu’s step of cyclization, which would have been desirable for Penu’s process because Penu teaches that the process further comprises the step of [0015] cyclization of the lactic acid oligomers and production of crude lactide and recycle of unreacted monomers, catalytic residues, and heavy products [0018], wherein recycle of the cyclization step is sent to a trans-esterification reactor [0023], where from the cyclization step, and besides the obtained crude lactide stream which will be sent to the purification, it is necessary to recover the unreacted oligomers, the non volatile impurities, the high boiling point lactic acid oligomer, the low molecular weight polylactic acid, as well as the heavy residues, and the catalytic residues which all form the cyclization residues [0030], wherein the cyclization residues are sent back to the oligomerization step, where a purge is absolutely needed to avoid dramatic accumulation of catalytic residues in the system as well as degradation by-products, and which also contribute to the elimination of impurities, wherein the products of the purge are then sent to the trans-esterification reactor [0031].
Correspondence
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/DAVID T KARST/Primary Examiner, Art Unit 1767
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