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 .
This communication responds to the application and amended claim set filed June 22,2023. Claims 1-29 are currently pending.
Priority
This application is the national stage entry of PCT/US2021/062342, filed December 8,2021, Applicant’s claims priority to U.S. Provisional Patent Application No. 63/129,891 filed December 23,2020 is ACKNOWLEDGED.
Election/Restrictions
Applicant’s election of Group I, claims 1-21 in the reply filed on January 20, 2026 is acknowledged. Applicant disagrees with the Examiner’s finding that Group I to IV lack unity. The traversal is not found persuasive because the restriction is based on the groups of the invention lacking unity of invention (a process for producing polyacrylonitrile-based fiber) between the groups is known in the art, and is therefore not special. Attention is drawn to the rejection below . Therefore, the requirement is still deemed proper and is therefore made FINAL.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(B) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-21 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, or for pre-AIA the applicant regards as the invention.
Claim 1 recites “the polyacrylonitrile-based material” in lines 11-12. There is insufficient antecedent basis for this limitation in the claim.
Claim 19 recites “the homogeneous solution comprises less than or equal to 50 wt.% relative to the total weight of the homogeneous solution”, which renders the claim indefinite. In view of the specification, the examiner is interpreting claim 19 is missing “of polymer B” after “50 wt.%”. The claim should recite “the homogeneous solution comprises less than or equal to 50 wt.% of polymer B relative to the total weight of the homogeneous solution”.
Claims 2-21 are rejected as being dependent on a rejected base claim.
Claim Rejections - 35 USC § 102
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 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.
Claims 1-8, 13-14 and 16-20 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Xiao et al. (CN101696517 (A); full English Machine translation incorporated herewith).
Regarding claim 1, Xiao et al. teach a process for producing a fiber which comprises:
-forming a blended solution of polyacrylonitrile (which correspond to polymer A), a water-soluble polymer including polyvinyl alcohol, polyethylene glycol or polyethylene oxide [0011] (which correspond to polymer B) and an organic solvent such as dimethylacetamide (which correspond to the first liquid) ([0013],claims 1 and 2), thereby reading on the step a);
-spinning the blended solution by using a wet spinning process to prepare a nascent fiber, wherein the coagulation bath is a mixture of water and dimethylacetamide ([0013], claim 1), wherein dimethylacetamide is a solvent for polymer A and water is a non-solvent for polymer A (which correspond to the second liquid), thereby reading on the step b);
- washing the resulting fibers with water (which correspond to the third liquid that is a non-solvent for polymer A and a solvent for polymer B) to remove the water-soluble polymer (polyvinyl alcohol) ([0013]-[0014], [0017], [0019] claim 1), thereby reading on the step c). It is noted that the water-soluble polymer functions as the removable polymer that generates a porous structure, wherein by appropriately selecting the average molecular weight and content of the water-soluble polymer to adjust its dispersion in solution, the size, structure and morphology of the micropores in the fiber can be controlled. ([0014], [0017]). Given that the process and components of Xiao et al. are substantially identical to the claimed invention, the polyacrylonitrile-based fiber of Xiao et al. will possess the claimed controlled morphology. Because the PTO does not have proper means to conduct experiments, the burden of proof is now shifted to Applicant to show otherwise. (See In re Best, 562 F.2d 1252, 195 USPQ 430 (CCPA 1977); In re Fitzgerald, 205 USPQ 594 (CCPA 1980).)
Regarding claims 2-3, Xiao et al. teach the first liquid is an organic solvent and the second liquid as a mixture of water and the organic solvent including dimethylacetamide, dimethylformamide, or dimethyl sulfoxide (claim 1, [0029], [0036]), as required by the instant claims.
Regarding claims 4-5, Xiao et al. teach the second liquid as a mixture of water and organic solvent including dimethylacetamide, dimethylformamide, or dimethyl sulfoxide (claim 1, [0029], [0036]), and the third liquid is water (claim 1, [0017]), as required by the instant claims.
Regarding claim 6, Xiao et al. teach the first liquid is an organic solvent including dimethylacetamide, dimethylformamide, or dimethyl sulfoxide (claim 1, [0029], [0036]), wherein the dimethylacetamide, dimethylformamide, or dimethyl sulfoxide are solvents for polymer A, as required by the instant claim.
Regarding claim 7, Xiao et al. teach the second liquid is a mixture of water and the organic solvent including dimethylacetamide, dimethylformamide, or dimethyl sulfoxide (claim 1, [0029]), wherein water is a non-solvent for polymer A and the organic solvent is a solvent for the polymer A [0019], as required by the instant claims.
Regarding claim 8, Xiao et al. teach the third liquid is water (claim 1, [0017], [0031]), wherein water is a non-solvent for polymer A, as required by the instant claim.
Regarding claims 13 and 14, Xiao et al. teach the water-soluble polymer is polyvinyl alcohol, polyethylene glycol, or polyethylene oxide polyvinyl alcohol ([0013], claim 1), thereby reading on the polymer B comprising repeating units derived from monomers according to the claimed formula (II) (homopolymer), as required by the instant claims. This disclosure of the claimed subject matter is sufficiently specific to constitute anticipation under 35 USC 102.
Regarding claim 16, the limitation was discussed in the rejection of claim 1, wherein Xiao et al. teach a process comprising the step of spinning the blended solution of polyacrylonitrile, a water-soluble polymer including polyvinyl alcohol [0011] and an organic solvent such dimethylacetamide by using a wet spinning process to prepare a nascent fiber, wherein the coagulation bath is a mixture of water and dimethylacetamide (second liquid) ([0013], claim 1), as required by the instant claim.
Regarding claim 17, Xiao et al. teach the nascent fibers are then stretched 1.5-5 times in a hot water bath (which correspond to the third liquid as discussed in the rejection of claims 1, 4-5) at a temperature of 80-99°C, and then thoroughly washed to obtain the fibers, as required by the instant claim.
Regarding claim 18, Xiao et al. teach the composition according to claim 1 as set forth above and incorporated herein by reference. Xiao et al. teach second liquid comprises a mixture of water and the organic solvent (i.e. dimethylacetamide, dimethylformamide or dimethyl sulfoxide), wherein the organic solvent has a volume percentage of 10-50% (claim 1), which is equivalent to 9wt.%-48.4 wt.% for dimethylacetamide (DMAc) as the organic solvent and 51.6-91 wt.% for the non-solvent for the polyacrylonitrile polymer (water), as required by the instant claim.
DMAc solvent (Vol. %)
(Density ≈ 0.937 g/cm3)
Water (Volume %)
(Density ≈ 1 gm/cm3
Mass% DMAc
Mass % Water
10 %
90 %
9 wt.%
91 wt.%
50 %
50 %
48.4 wt.%
51.6 wt.%
[AltContent: connector]Mass % of DMAc = (V(DMAc)) (Density(DMAc))
(V(DMAc)) (Density(DMAc)) + (V(water)) (Density(water))
Regarding claim 19, Xiao et al. teach dried polyacrylonitrile and a water-soluble polymer are blended at a mass percentage of 70–95:5–30, dissolved in an organic solvent, and heated and stirred at 50–70°C for 3–5 hours to obtain a blended spinning solution with a concentration of 15–30% (claim 1). Therefore, the polymer concentration ranges between 15-30 wt.% and the concentration of the water-soluble polymer (PVA) ranges between 5-30 wt.%, which is equivalent to 0.75 wt.% to 9 wt.% of polyvinyl alcohol (i.e. highest concentration : 0.3 x 0.3 = 0.09 x 100 = 9%), as required by the instant claim.
Regarding claim 20, Xiao et al. further teach a step of drying the after the washing step c) [0039], as required by the instant claim.
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.
Claims 9 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Xiao et al. (CN101696517 (A)) in view of Ohmory et al. (U.S. Patent No. 5861213 A and/or EP 0769579 B1 as listed on the IDS dated 7/03/2025).
Xiao et al. teach the composition according to claim 1 as set forth above and incorporated herein by reference.
Regarding claim 9, Xiao et al. are silent on the acrylonitrile polymer comprising a comonomer.
However, Ohmory et al. teach a process for producing a fiber, wherein a vinyl alcohol polymer (PVA) and an acrylonitrile polymer (PAN) are dissolved in a common solvent (i.e. DMSO) to prepare a spinning solution, followed by the wet spinning of the solution in a coagulation bath containing a mixture of an organic solvent and the solvent used spinning solution (i.e. methanol and DMSO), then the resulting yarn is subjected to wet drawing, extraction and drying, prior to the transfer to dry heat drawing process, wherein the extraction bath comprises alcohol, ketones and water (abstract, col. 6-8, example 1). Ohmory et al. further teach the polyacrylonitrile polymer contains an acrylonitrile unit at 70 mole % or more and comonomers at a ratio of 30 mole% or less such as (metha)acrylates including methyl acrylate, ethyl acrylate, methyl methacrylate; vinyl esters for example vinyl acetate and vinyl lactate; vinyl compounds for example vinyl chloride; unsaturated carboxylic acids for example acrylic acid, methacrylic acid, and maleic anhydride; and vinyl compounds containing sulfonic acid. Ohmory et al. offers the motivation of using acrylonitrile monomer copolymerized with the monomers to improve the solubility in the solvent of the spinning solution (col.3:63-67 and col.4: 1-10) and to obtain a fiber with high strength (col.3:15-22). ]). In light of these benefits, it would have been obvious to one of ordinary skill in the art to use the acrylonitrile copolymer taught by Ohmory et al. on the acrylonitrile based fiber of Xiao et al., thereby arriving at the claimed invention.
Regarding claim 15, Xiao et al. are silent on the polymer B is a copolymer as recited in the instant claim.
However, Ohmory et al. teach the PVA is a polymer containing the vinyl alcohol unit a 70 mole% or more, and the polymer may therefore be copolymerized with monomers at a ratio of less than 30 mole% such as ethylene, vinyl acetate, itaconic acid, acrylamide, among others (col.3:24-42), which implies the PVA can be a homopolymer or a copolymer. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have substituted the PVA copolymer as taught by Ohmory et al. in place of the PVA of Xiao et al. with the expectation of improving the mechanical properties of the polyacrylonitrile -based fiber (See MPEP 2143(I)(B).)
Claims 10 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Xiao et al. (CN101696517 (A)) in view of Cerf et al. (US PG Pub. 2004/0068069)
Xiao et al. teach the composition according to claim 1 as set forth above and incorporated herein by reference.
Regarding claim 10, Xiao et al. teach forming porous acrylonitrile fibers by blending a polyacrylonitrile polymer with a water-soluble polymer that acts as a pore stabilizer, followed by spinning and removal of the water-soluble polymer by washing with water to generate pores ([0004], [0007][0012]-[0014]). Xiao et al. further teach the water-soluble polymer is selected based on the following requirements: solubility in organic solvents that dissolve polyacrylonitrile, form a stable spinning solution with PAN, remain in the fiber during spinning, be removable by washing with water, have a relatively large average relative molecular to ensure the creation of pores in the fibers [0018]-[0025], which implies other water-soluble polymers satisfying the above requirements can be used.
Xiao et al. are silent on the polymer B comprising repeating units derived from a monomer according to formula (I). Xiao et al. are further silent on the polymer B is a homopolymer.
Cerf et al. teach a method for making acrylonitrile fibers, wherein Cerf et al. teach the polyacrylamide polymer is a water-soluble polymer that is used in polyacrylonitrile systems as a dispersant or stabilizer together with polyvinyl alcohol [0024]. Cerf et al. teach the polyacrylamide polymer as a functional equivalent of the polyvinyl alcohol as disclosed by Xiao et al. Given that the polyacrylamide polymer is a water-soluble polymer and possess similar solution properties, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use a polyacrylamide homopolymer as the water-soluble polymer with the expected result of acting as a removable pore-forming agent that would improve the hydrophilicity and mechanical properties of the fibers, consistent with Xiao et al. teaching.
Claim 21 is rejected under 35 U.S.C. 103 as being unpatentable over Xiao et al. (CN101696517 (A)) as evidenced by Previdi (WO-2014/170924 A) for claim 21.
Regarding claim 21, Xiao et al. teach the composition according to claim 1 as set forth above and incorporated herein by reference. Xiao et al. teach the PVA is removed by washing with water during the process of producing the fibers [0014].
Xiao et al. are silent on the step e) of recovering at least partially the polymer B, however it is an industrial practice to recover and reuse polymers and solvents from washing baths. Therefore, it would be obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to implement a step of recovery of the PVA from the washing bath by using filtration, membrane separation and concentration as evidenced by Previdi (abstract).
Allowable Subject Matter
Claim 12 is objected to as being dependent upon a rejected based claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
The prior arts of record (CN101696517 (A), U.S. Patent No. 5861213, US PG Pub. 2004/0068069) fail to teach or suggest a process for producing polyacrylonitrile based fiber, wherein the process comprises, in particular, the polymer B that is a copolymer comprising greater than or equal to 50 percent by weight of monomeric units derived from a monomer according to formula (I).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to OLGA L. DONAHUE whose telephone number is (571)270-1152. The examiner can normally be reached M-F 8:00-5:00.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, JOSEPH DEL SOLE can be reached at 571-272-1130. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/OLGA LUCIA DONAHUE/Examiner, Art Unit 1763
/CATHERINE S BRANCH/Primary Examiner, Art Unit 1763