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 .
Claim Status
The Amendment filed on 03 June 2026 has been entered; claims 1-7 remain pending.
Response to Arguments
Applicant’s arguments, see Page 5 of the Remarks, filed 03 June 2026, with respect to the rejection of claim 3 under 35 USC 112(b) have been fully considered and are persuasive. The rejection of claim 3 under 35 USC 112(b) has been withdrawn in light of Applicant’s amendments to the claims.
Applicant's arguments, see Pages 5-6 of the Remarks, filed 03 June 2026, with respect to the rejections of claims 1-4 under 35 USC 103 have been fully considered but they are not persuasive. Applicant points to Comparative Example 5, in which a membrane comprising polyether sulfone could not be formed; however, this argument is not commensurate in scope with claim 1, as “polyether sulfone” is a family of polymers which includes polyarylene ether sulfone, so all embodiments of the membrane disclosed by Nakao aside from Comparative Example 5, as discussed in the rejection below in detail.
Dependent claim 5, which recites a polyether sulfone comprising the recited subunit from Paragraph [0024] of the specification, has been objected to for being dependent on claim 1, but is otherwise allowable as Nakao teaches away from polyether sulfone as recited in claim 5.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-4, 6, and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Nakao et al. (U.S. Patent Publication # 2015/0314245), hereinafter “Nakao”.
With respect to claim 1, Nakao teaches a composite separation membrane (Abstract) which is permeable to water and rejects salt (“semipermeable”) (Paragraph [0057]), comprising: a porous support membrane comprising polyvinylpyrrolidone (Paragraph [0080]) and a separation layer comprising a sulfonated polyarylene ether copolymer which includes a hydrophobic segment repeating unit represented by the recited formula (1) and a hydrophilic segment repeating unit represented by the recited formula (2) as copolymerization components (see Paragraphs [0050, 0109]), wherein a sum of the component ratio (in mole) of the formula (1) and the component ratio (in mole) of formula (2) is 1.00 (no other monomers disclosed), wherein R1 and R2 represents -SO3M where M = a metallic element (Paragraphs [0052, 0109, 0110]), wherein repeat segments of formula (2) are present at more than 10% and less than 70% (and there the balance of more than 30% and less than 90% of repeat segments of formula (1)), which encompasses 35 to 50% or 0.35 to 0.50 mole ratio component for formula (2) and 50 to 65% or 0.50 to 0.65 mole ratio component for formula (1).
Nakao and the claims differ in that Nakao does not teach the exact same proportions for the mole fraction of each of the hydrophobic and hydrophilic segments as recited in the instant claims; however, one of ordinary skill in the art at the time the invention was made would have considered the invention to have been obvious because the compositional proportions taught by Nakao overlap the instantly claimed proportions for the hydrophobic and hydrophilic segments, and therefore are considered to establish a prima facie case of obviousness. It would have been obvious to one of ordinary skill in the art to select any portion of the disclosed ranges including the instantly claimed ranges from the ranges disclosed in Nakao, particularly in view of the fact that; “The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages”, In re Peterson, 65 USPQ2d 1379 (CAFC 2003).
Regarding the recited ratio of (the polyether sulfone)/(the sulfonated polyarylene ether copolymer)/(the polyvinylpyrrolidone), the Examiner submits that the sulfonated polyarylene ether copolymer is a polyether sulfone. Thus, in order to determine the ratio of (the sulfonated polyarylene ether copolymer)/(the polyvinylpyrrolidone) disclosed by Nakao, it is noted that Nakao teaches that the composite semipermeable membrane comprises a porous support layer comprising polyvinylpyrrolidone at present at preferably greater than 0 to less than 20% of the porous support membrane as a filler (see Paragraph [0080]), while the porous support layer is about 5 to 500 microns thick (Paragraph [0097]) and the separation layer (which contains the sulfonated polyarylene ether copolymer) is about 50 to 500 nm thick (Paragraph [0073]).
Taking the example of when the separation layer is 500 nm or 0.5 microns and the porous support layer is 5 microns, the content of the sulfonated polyarylene ether copolymer (which is a polyether sulfone) is 1/10 the amount of the porous support layer which comprises greater than 0 and less than 20% polyvinylpyrrolidone. Taking 1% polyvinylpyrrolidone as the amount in the support layer, the ratio of sulfonated polyarylene ether copolymer to polyvinylpyrrolidone is 1% of 10 or 0.1 to 1 sulfonated polyarylene ether copolymer (which is a polyether sulfone), or 10% of the total, which falls within “3 to 18” recited for polyvinylpyrrolidone, with the balance being sulfonated polyarylene ether copolymer at 90%. The foregoing was simply an example depicting that at least one embodiment disclosed by Nakao overlaps with the recited mass ratio range. The Examiner appreciates that this is a crude estimate based on thickness of the layers; however, it is submitted that the ordinary artisan would have found the recited semipermeable membrane obvious over the teachings of Nakao.
Nakao and the claims differ in that Nakao does not teach the exact same proportions for the mass fraction of each of the polymers as recited in the instant claims; however, one of ordinary skill in the art at the time the invention was made would have considered the invention to have been obvious because the compositional proportions taught by Nakao overlap the instantly claimed proportions for the disclosed polymers, and therefore are considered to establish a prima facie case of obviousness. It would have been obvious to one of ordinary skill in the art to select any portion of the disclosed ranges including the instantly claimed ranges from the ranges disclosed in Nakao, particularly in view of the fact that; “The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages”, In re Peterson, 65 USPQ2d 1379 (CAFC 2003).
Additionally, it is submitted that there is no evidence indicating such mass ratios for the polymers are critical. Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. See In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
With respect to claim 2, the composite membrane of Nakao has a porous support layer that is about 5 to 500 microns thick (Paragraph [0097]) and a separation layer (which contains the sulfonated polyarylene ether copolymer) which is about 50 to 500 nm thick (Paragraph [0073]), therefore, the structure is not uniform in a thickness direction (see also Figs. 3, 4).
With respect to claim 3, Nakao teaches that the porous support has large pores (i.e., is less dense) than the separation layer (see Paragraphs [0033, 0067, 0068]; Figs. 3, 4), and further teaches that the casting/doping solution is applied to the inner surfaces of the hollow fiber membranes, forming the separation layer which has a smaller pore size than the porous support oriented to the outside of the hollow fibers (see Paragraph [0117]), meeting the limitations “the pore size increasing from inner surface to the outer surface continuously or discontinuously”.
With respect to claim 4, regarding the limitations “wherein a NaOH titration amount for the entirety of the semipermeable membrane is from 1.2 to 3.0 mL”, the Examiner submits that Nakao renders obvious all of the components of the membrane, and therefore the NaOH titration amount for the entirety of the semipermeable membrane is presumed to be an inherent property of the membrane of Nakao. It has been held that where the Patent Office has reason to believe that a functional limitation asserted to be critical for establishing novelty in the claimed subject matter may, in fact, be an inherent characteristic of the prior art, it possesses the authority to require applicant to prove that the subject matter shown to be in the prior art does not possess the characteristic relied upon. In re Swinehart, 439 F.2d 210, 169 USPQ 226 (CCPA 1971). The Examiner further submits that these limitations pertain to a specific method of using the recited membrane; the membrane of Nakao is capable of NaOH titration.
With respect to claim 6, Nakao teaches that the semipermeable membrane is a hollow fiber membrane made of a hollow fiber spun from a dope (see Paragraph [0085]).
With respect to claim 7, Nakao teaches that the semipermeable membrane is asymmetric (see Paragraphs [0084, 0088]).
Allowable Subject Matter
Claim 5 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims, as none of the prior art teaches or suggests the semipermeable membrane of claim 5, comprising polyether sulfone embodied as claimed. Regarding polyether sulfone, Nakao actually teaches away from using this polymer to make the porous membrane support, due to the solubility of polyether sulfone in various solvents (see Paragraphs [0028-0031]; Table 1; and see Comparative Ex. 5).
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CLARE M PERRIN whose telephone number is (571)270-5952. The examiner can normally be reached 9AM-6PM EST M-F.
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/CLARE M. PERRIN/
Primary Examiner
Art Unit 1779
/CLARE M PERRIN/Primary Examiner, Art Unit 1779 24 July 2026
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