DETAILED ACTION
Notice of Pre-AIA or AIA Status
1. The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
2. A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 09/16/2025 has been entered.
Status of the Claims
3. Claims 1-2 and 8-9 are currently pending. This office action is in response to the amendment filed on 09/16/2025.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
4. Claims 1-3, 8 are rejected under 35 U.S.C. 103 as being unpatentable over Li ‘394 ( CN 104558394 A; all citations refer to the English language machine translation which is provided).
Concerning claims 1-3, 5, 8 Li ‘394 teaches a polyacrylonitrile polymer used for a carbon fiber (paragraph 0002-0005). Li ‘394 teaches that the polymer is made from monomers of acrylonitrile comonomer 1 and comonomer 2 (paragraph 0010) where comonomer 1 is preferably one of a list of monomers that can include itaconic acid and comonomer 2 is sodium propylene sulfonate or sodium methpropene sulfonate (paragraph 0010). The monomer amounts are given to be 10-35 parts by weight of acrylonitrile (AN) 1 to 10 parts of the comonomer 1 of itaconic acid (IA) and 0.1 to 10 parts of comonomer 2 (SULF) which is the sulfonate monomer (paragraph 0011). Acrylonitrile has a molecular weight of approximately 53.064 g/mol itaconic acid has a molecular weight of approximately 130.099 g/mol and sodium propylene sulfonate has a molecular weight of approximately 144.13 g/mol. This can be used to determine the mol% of the monomers present in the polymer and indicates that when sodium propene sulfonate is used it ranges from 15.28 mol% (20 parts AN, 1 part IA and 10 part SULF) to 0.12 mol% (30 part AN 10 part IA and 0.1 part SULF). The amount of Itaconic acid ranges from 16.91 mol% (20 part AN, 10 part IA and 0.1 part SULF) to 1.04 mol% (35 parts AN, 1 part IA and 10 part SULF). It should also be noted that a copolymer of 35 parts acrylonitrile, 1 part of itaconic acid and 1 part of sodium propene sulfonate results is 1.03 mol% of sodium allyl sulfonate and 1.14 mol% of itaconic acid. As such Li ‘394 teaches an overlapping range with the claimed range of the amounts of the sulfonate based monomer unit and carboxylic acid based monomer unit.
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). See MPEP 2144.05.I.
Li ‘394 teaches that the sulfonate containing monomer can be one of two monomers that includes sodium propylene sulfonate (paragraph 0010). Sodium propyl2-ene 1-sulfonate is another name for sodium allyl sulfonate which would be a monomer of the claimed structure.
It would have been obvious to one of ordinary skill in the art at the time of filling to use the claimed amount of the claimed sulfonate based monomer unit and the carboxylic acid based monomer unit because Li ‘394 teaches amounts of these units that are an overlapping range with the claimed range and teaches the claimed sulfonate containing monomer, and to use a carboxylic acid based monomer unit such as that of itaconic acid because Li ‘394 teaches that itaconic acid is one of the preferable monomers to be used in the polymer.
Alternatively if sodium propylene sulfonate is not sodium allyl sulfonate or sodium methallyl sulfonate then it would be a position isomer with the sodium allyl sulfonate of the claimed monomer structure.
A prima facie case of obviousness may be made when chemical compounds have very close structural similarities and similar utilities. "An obviousness rejection based on similarity in chemical structure and function entails the motivation of one skilled in the art to make a claimed compound, in the expectation that compounds similar in structure will have similar properties." In re Payne, 606 F.2d 303, 313, 203 USPQ 245, 254 (CCPA 1979). See MPEP 2144.09.I.
Compounds which are position isomers (compounds having the same radicals in physically different positions on the same nucleus) or homologs (compounds differing regularly by the successive addition of the same chemical group, e.7g., by -CH2- groups) are generally of sufficiently close structural similarity that there is a presumed expectation that such compounds possess similar properties. In re Wilder, 563 F.2d 457, 195 USPQ 426 (CCPA 1977). See MPEP 2144.09.II.
Prior art structures do not have to be true homologs or isomers to render structurally similar compounds prima facie obvious. In re Payne, 606 F.2d 303, 203 USPQ 245 (CCPA 1979). See MPEP 2144.09.III.
It would have been obvious to one of ordinary skill in the art at the time of filling to alter the sodium propene sulfonate monomer of Li ‘‘394 to match that of the claimed sodium allyl sulfonate monomer in the polymer of Li ‘‘394 because these monomer compounds have very close structural similarities and similar utilities.
5. Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Li ‘394 ( CN 104558394 A; all citations refer to the English language machine translation which is provided) as applied to claim 1 above, and further in view of Hamada (US 6,326,451 B1).
Concerning claim 9 Li ‘394 teaches the acrylonitrile based copolymer for a carbon fiber as is indicated in the discussion of claim 1 above.
Li ‘394 further teaches that the acrylonitrile based copolymer is made into a spinning dope that is then spun into a polyacrylonitrile raw filament (paragraph 0006).
Li ‘394 does not specifically teach the claimed circularity of the fiber being 1.13 or less.
Hamada is drawn to acrylonitrile based precursor fibers for the formation of carbon fibers (column 1 liens 10-15) which include carboxylic acid groups and sulfonic groups (column 4 lines 30-45) and teaches that it is beneficial to produce precursor fibers that are substantially circular in which the ratio of the major axis to the minor axis is not greater than 1.1 because such fibers having the indicated shape when they are used in a stabilization step are uniformly flame proofed and carbonized in the cross sectional directions of the fibers so that carbon fibers having higher performance can be obtained (column 9 lines 10-50).
Applicants specification indicates that circularity may be measured by determining the ratio of the major axis to the minor axis (applicant specification pg 4 lines 5-10)
It would have been obvious to one of ordinary skill in the art at the time of filling to alter the fibers formed from Li ‘222 to have a circularity of not greater than 1.1 as taught by Hamada because such fibers would produce carbon fibers having higher performance.
Response to Arguments
6. Applicant's arguments filed 09/16/2025 have been fully considered but they are not persuasive. Applicant argues with regard to the rejection over Li ‘394 that the grouds for rejection fail to consider the teachings of Li ‘394 as a whole and what the reference as a whole would have suggested to a person of ordinary skill in the art. For instance the examples disclosed in li ‘394 teach away from the conditions required by the claims of the invention. To be specific the examples of Li ‘394 do not comply to the conditions described int eh claims of the invention even after converting to the weight fraction. IN summery, the mixing ratio of the polymerization raw materials generally disclosed by Li ‘394 is completely different form the examples. Accordingly a skilled person in the art would not consider the mixing ratio of the polymerization raw materials disclosed in Li ‘394 which does not disclose critical significance of the numerical limitation and the effects thereof were not proved through experiments as a broad and preferable range even after referring to Li ‘394.
This argument is not found to be persuasive because Li ‘394 teaches that the monomer amounts are given to be 10-35 parts by weight of acrylonitrile (AN) 1 to 10 parts of the comonomer 1 of itaconic acid (IA) and 0.1 to 10 parts of comonomer 2 (SULF) which is the sulfonate monomer (paragraph 0011). Acrylonitrile has a molecular weight of approximately 53.064 g/mol itaconic acid has a molecular weight of approximately 130.099 g/mol and sodium propylene sulfonate has a molecular weight of approximately 144.13 g/mol. This can be used to determine the mol% of the monomers present in the polymer and indicates that when sodium propene sulfonate is used it ranges from 15.28 mol% (20 parts AN, 1 part IA and 10 part SULF) to 0.12 mol% (30 part AN 10 part IA and 0.1 part SULF). The amount of Itaconic acid ranges from 16.91 mol% (20 part AN, 10 part IA and 0.1 part SULF) to 1.04 mol% (35 parts AN, 1 part IA and 10 part SULF). It should also be noted that a copolymer of 35 parts acrylonitrile, 1 part of itaconic acid and 1 part of sodium propene sulfonate results is 1.03 mol% of sodium allyl sulfonate and 1.14 mol% of itaconic acid. As such Li ‘394 teaches an overlapping range with the claimed range of the amounts of the sulfonate based monomer unit and carboxylic acid based monomer unit.
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). See MPEP 2144.05.I.
"The use of patents as references is not limited to what the patentees describe as their own inventions or to the problems with which they are concerned. They are part of the literature of the art, relevant for all they contain." In re Heck, 699 F.2d 1331, 1332-33, 216 USPQ 1038, 1039 (Fed. Cir. 1983). See MPEP 2123.I.
A reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including nonpreferred embodiments. Merck & Co. v. Biocraft Labs., Inc. 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir. 1989), cert. denied, 493 U.S. 975 (1989). See MPEP 2123.I.
Disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. In re Susi, 440 F.2d 442, 169 USPQ 423 (CCPA 1971). "A known or obvious composition does not become patentable simply because it has been described as somewhat inferior to some other product for the same use." In re Gurley, 27 F.3d 551, 554, 31 USPQ2d 1130, 1132 (Fed. Cir. 1994). See MPEP 2123.II.
As such that the examples do not particularly teach the claimed mol% value of the sulfate based monomer unit and the carboxylic acid based monomer unit can not be considered to teach away from the broad disclosure of the amounts of the indicated monomers which can be used in the polymer, which as already stated is an overlapping range with the claimed range.
Applicant further argues that Li ‘394 discloses that the molecular weight and viscosity of the spinning solution can be adjusted by controlling the elements of comonomer 2, more specifically using sodium allyl sulfonate or sodium methallyl sulfate as comonomer 2 and using azobisisoheptanitile as an initiator at the same time. However, it fails to disclosed, suggest or imply that the molecular weight and viscosity of the spinning solution can be adjusted by controlling the amount of comonomer 2. Accordingly a skilled person in the art would not be motivated to control the amount of carboxylic acid based monomer units and sulfonate based monomer unit by referring to Li ‘394.
This argument is not found to be persuasive because Li ‘394 teaches that the monomer amounts are given to be 10-35 parts by weight of acrylonitrile (AN) 1 to 10 parts of the comonomer 1 of itaconic acid (IA) and 0.1 to 10 parts of comonomer 2 (SULF) which is the sulfonate monomer (paragraph 0011). Acrylonitrile has a molecular weight of approximately 53.064 g/mol itaconic acid has a molecular weight of approximately 130.099 g/mol and sodium propylene sulfonate has a molecular weight of approximately 144.13 g/mol. This can be used to determine the mol% of the monomers present in the polymer and indicates that when sodium propene sulfonate is used it ranges from 15.28 mol% (20 parts AN, 1 part IA and 10 part SULF) to 0.12 mol% (30 part AN 10 part IA and 0.1 part SULF). The amount of Itaconic acid ranges from 16.91 mol% (20 part AN, 10 part IA and 0.1 part SULF) to 1.04 mol% (35 parts AN, 1 part IA and 10 part SULF). It should also be noted that a copolymer of 35 parts acrylonitrile, 1 part of itaconic acid and 1 part of sodium propene sulfonate results is 1.03 mol% of sodium allyl sulfonate and 1.14 mol% of itaconic acid. As such Li ‘394 teaches an overlapping range with the claimed range of the amounts of the sulfonate based monomer unit and carboxylic acid based monomer unit.
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). See MPEP 2144.05.I.
It should be noted that it is assumed that applicant meant to refer to the monomer 1 of Li ‘394 above as this is the monomer which can be itaconic acid, a carboxylic acid. The fact that Li ‘394 does not state that the molecular weight and viscosity of the spinning solution can be adjusted by controlling the amount of comonomer 1 which can be itaconic acid does not change the fact that Li ‘394 states that the comonomer is present in the polymer in a particular amount and as such teaches a range of the amount of this monomer that can be present which as is stated above overlaps with the claimed range of the monomer. As such one of ordinary skill in the art at the time of filling would recognize that this monomer must be controlled within the limits set by Li ‘394 and as this is an overlapping range with the claimed range would render the claimed amount of the monomer as obvious. As such the rejections provided above are maintained.
Applicant further argues concerning the rejection over Li ‘394 in view of hamada that the combination of li ‘394 and Hamada also do not render obvious the composition of claim 1 for the reasons stated above.
This argument is not found to be persuasive for the reasons indicated concerning the arguments of Li ‘394 as stated above. As such the rejection is maintained.
Conclusion
7. Claims 1-2, 8-9 are rejected. No claims are currently allowable.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DAVID L MILLER whose telephone number is (571)270-1297. The examiner can normally be reached M-F 9:30-6:00.
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/DAVID L MILLER/ Examiner, Art Unit 1763
/JOSEPH S DEL SOLE/Supervisory Patent Examiner, Art Unit 1763