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
Claims 1-20 are pending:
Claims 1-13 and 20 are rejected.
Claims 14-19 have been withdrawn.
Response to Amendment
Amendment filed 07/24/2026 have been entered. Amendments to the claims do not overcome §103 rejections as previously set forth in non-final Office Action mailed 03/24/2026.
Amendments to the claims have necessitated new grounds of rejection using prior art of record under §103 and §112.
Response to Arguments
Arguments filed 07/24/2026 have been entered. Arguments were fully considered.
On pgs 8-9, of Applicant’s arguments, Applicant’s argues that:
Paragraph [0032] of the specification explains: "The fact that the value imin is within the [claimed] range means that the region Sai having an average diameter smaller than the average diameter Dai in the region closest to the first surface and equal to the average diameter Db2 of the spherical structure of the region Sb2 is located closer to the second surface than Sa2. Accordingly, a clogging component can be more widely dispersed in the thickness direction of the membrane." Similarly, the gradual reduction in average diameter of the spherical structure helps to more widely disperse the clogging component in the thickness direction of the membrane. Therefore, as explained in paragraph [0032], an operation period can be lengthened.
Paragraph [0039] further explains: "When ... the average diameter of the spherical structures is gradually reduced from the first surface, and thus imin can be increased, and improvement in the filterability is expected."
Iwai, however, fails to disclose or suggest a gradual reduction in the average diameter of the spherical structure from the first surface toward the second surface. In fact, the teachings in Iwai would lead one of ordinary skill in the art away from this claimed feature.
In paragraph [0058], Iwai discloses: "In the separation membrane of the present invention, the average diameter D3 of a spherical structure S3 in a region of 10 pM to 20 pM from the first surface and the average diameter D2 of a spherical structure S2 in a region of 10 pm to 20 pm from the second surface preferably satisfy the relationship of -0.30 pm<(D3-D2)<0.30 um." In other words, Iwai teaches that the average diameter of the spherical structure remains essentially the same between a region of 10 pm to 20 pm from the first surface to a region of 10 pm to 20 pm from the second surface.
Iwai further discloses a membrane structure in which large spherical structures are present only in the vicinity of the outer surface. Paragraph [0059] explains that the average diameter specifically in the region within 10 pm from the first surface is larger than the average diameter in the remainder of the separation membrane ([0059] of Iwai: "More specifically, out of the entire separation membrane, the spherical structure diameter in a surface layer portion as a region within 10 um from the surface on the liquid-to-be-treated side is set to be relatively larger than the spherical structure diameter in other portions of the separation membrane.").
In summary, Iwai therefore teaches that the average diameter generally decreases only between the region within 10 pm from the first surface and the adjacent region of 10 pm to 20 pm from the first surface, and that the average diameter remains constant over the remainder of the membrane until at least a region of 10 pm to 20 pm from the second surface. Or, in other words, Iwai teaches a sharp decline of the average diameter between the first surface to 10-20 pm from the first surface, and then essentially no change in the average diameter after that point when moving toward the second surface. Iwai, therefore, clearly does not teach a gradual reduction from the first surface toward the second surface as claimed.
Iwai further explains that this disclosed structure, namely where the diameter only in the region within 10 pm from the surface is larger than in other portions, contributes to achieving the intended effects of the invention (para. [0059] of Iwai: "...whereby the effects of the present invention are achieved and a separation membrane satisfying both high water permeation performance and high strength/elongation in a balanced manner is obtained").
Therefore, Applicant respectfully submits that not only does Iwai fail to disclose or suggest the average diameter Dan of the spherical structure being gradually reduced from the first surface toward the second surface as claimed, but one of ordinary skill in the art would clearly understand Iwai to be teaching away from this feature. Furthermore, from the standpoint of the membrane-forming mechanism, it would not have been obvious to make the pore size decrease gradually in a membrane formed by thermally induced phase separation and having a homogeneous structure.
In summary, Applicant respectfully submits that Iwai fails to teach, suggest, or render obvious the combination of features as recited in claim 1. Applicant respectfully submits that claim 1, and all claims dependent thereon, are distinguishable over the cited art. Withdrawal of the obviousness rejection, therefore, is respectfully requested.
This argument is persuasive in light of amendments because Example 6 of Iwai does not teach that “the average diameter Dan of the spherical structure is gradually reduced from the first surface toward the second surface” and “the average diameter Dan of the spherical structure is gradually reduced from the average diameter Dai in a region Sai to an average diameter Daimin in a region Samin”.
However, Comparative Example 3 (see Table 2 and ¶182-¶183) of Iwai further teaches that the average diameter Dan of the spherical structure is gradually reduced from the first surface toward the second surface (D1 = 3.35 um, D2 = 3.11 um and D3 = 3.06 um). Comparative Example 3 further discloses that D1/D3 = 1.09 which is only 0.01 from the claimed Da1/Dai ≥ 1.1 value, and therefore statistically within an error of margin.
It would have been obvious to one ordinary skill in the art before the effective filing date of the invention to modify the membrane spherical diameter of Iwai (as disclosed in Example 6) by gradually reducing said spherical diameter from the first surface toward the second surface as disclosed by an alternative embodiment of Iwai (comparative Example 3) because such diameter reduction increases water permeation performance (Iwai, see ¶183) and optimizes the balance between permeability and mechanical strength; and one of ordinary in the art would have a reasonable expectation of success because Example 6 of Iwai suggests particle reduction at least from D1 > D3 (Iwai, i.e. D1 = 2.58 um, D3 = 1.96 um).
Therefore, the §103 rejection has been updated using prior art of record.
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 1-13 and 20 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 applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. Dependent claims are hereby rejected due to dependency from rejected claim 1.
Claims 1 and 20 recite “gradually reduce”; the term “gradually” is a relative term thus rendering the claim indefinite. The term “gradually” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Additionally, it is unclear whether each successive region must decrease or whether the reduction must continue throughout the entire membrane thickness and it is unclear what % reduction falls under the scope of gradually reducing (i.e. 5% vs 20%).
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.
Claims 1-4, 6-7, 12 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Iwai (US 2017/0157572).
Regarding claim 1, Iwai teaches a hollow fiber membrane (hollow fiber membrane, see ¶170) comprising a layer of a spherical structure (spherical structure layer, see ¶142) of a resin (resin solution, see ¶187),
wherein the layer of the spherical structure has a thickness L of 60 um or more and 500 um or less (thickness preferably between 50 um to 350 um, see ¶67 which overlaps with the claimed range).
The examiner takes note of the fact that the prior art range of 50 – 350 um overlaps the claimed range of 60 – 500 um. Absent any additional and more specific information in the prior art, a prima facie case of obviousness exists. In re Peterson, 315 F.3d 1325, 1330, 65 USPQ2d 1379 (Fed. Cir. 2003). MPEP 2144.05.
With respect to the limitation, “the layer of the spherical structure has a first surface and a second surface, an average diameter Dan of the spherical structure in a region San of 10 x (n - 1) to 10 x n um from the first surface and an average diameter Dbn of the spherical structure in a region Sbn of 10 x (n - 1) to 10 x n um from the second surface satisfy a relation of Da1 > Db2, and a minimum value imin of a natural number i satisfying the following conditions (1) and (2) satisfies a relation of 3 ≤ imin ≤ (L - 20)/10, (1) Da1/Dai ≥1.1 (2) -0.3 pm Da1-Db2 0.3 pm provided that n is a natural number, and in the relation of 3 ≤ imin ≤ (L - 20)/10, a decimal point or less of (L - 20)/10 is truncated” and “wherein a relation of imin L x 0.75/10 is satisfied, provided that in the relation of imin L x 0.75/10, a decimal point or less of L x 0.75/10 is truncated”, example 6 discloses a membrane having diameter relationships: D1 = 2.58 um, D2 = 1.86 um, D3 = 1.96 um, D1/D3 = 1.32 and D3 - D2 = 0.10 um therefore example 6 demonstrates that the spherical relationships required by conditions (1) and (2) occur within the membrane; but Iwai does not disclose imin (or the depth) at these conditions as required by claims 1-2.
Regarding claims 1-2, it would have been obvious to one ordinary skill in the art before the effective filing date of the invention to modify the membrane spherical diameter of Iwai by controlling routine spinning and cooling conditions, and adjusting these parameters to shift the transition deeper into the separation membrane would have been obvious by routine optimization with a reasonable expectation of success. Additionally, one of ordinary skill in the art would have had a reasonable expectation of success because Iwai already demonstrates the claimed diameter relationships within the membrane, and merely shifting the location at which these relationships occur within the membrane thickness does not produce a structurally distinct membrane. “[W]here 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).
Example 6 of Iwai does not teach that the average diameter Dan of the spherical structure is gradually reduced from the first surface toward the second surface.
Comparative Example 3 (see Table 2 and ¶182-¶183) of Iwai further teaches that the average diameter Dan of the spherical structure is gradually reduced from the first surface toward the second surface (D1 = 3.35 um, D2 = 3.11 um and D3 = 3.06 um). Comparative Example 3 further disclose that D1/D3 = 1.09 which is only 0.01 from the claimed Da1/Dai ≥ 1.1 value, and therefore statistically within an error of margin.
It would have been obvious to one ordinary skill in the art before the effective filing date of the invention to modify the membrane spherical diameter of Iwai (as disclosed in Example 6) by gradually reducing said spherical diameter from the first surface toward the second surface as disclosed by an alternative embodiment of Iwai (comparative Example 3) because such diameter reduction increases water permeation performance (Iwai, see ¶183) and optimizes the balance between permeability and mechanical strength; and one of ordinary in the art would have a reasonable expectation of success because Example 6 of Iwai suggests particle reduction at least from D1 > D3 (Iwai, i.e. D1 = 2.58 um, D3 = 1.96 um).
Regarding claim 3, Iwai teaches the hollow fiber membrane according to claim 1, wherein a relation of 1.10 < Da1/Daimin < 4.00 is satisfied (i.e. D1/D3 1.32).
Regarding claim 4, Iwai teaches the hollow fiber membrane according to claim 1, wherein a relation of 0.50 um < Db2< 2.00 um is satisfied (i.e. D2 = 1.86 um).
Regarding claim 6, Iwai teaches the hollow fiber membrane according to claim 1, wherein the first surface is on a side of liquid to be filtered (the separation membrane is usually used by arranging the first surface to come into contact with liquid to be treated, see ¶33 and ¶36).
Regarding claim 7, Iwai teaches the hollow fiber membrane according to claim 1, wherein the first surface is an outer surface of the hollow fiber membrane (this configuration is implied in ¶51).
Regarding claim 12, Iwai teaches the hollow fiber membrane according to claim1, wherein the spherical structure comprises a polyvinylidene fluoride-based resin (see claim 14), a hydrophilic polymer (a polyhydric alcohol, see ¶44) is present on a surface and inside of the spherical structure (the polyhydric alcohol gets mixed with the resin, see ¶44 which implies this additive ends up throughout the membrane matric including pore surfaces therefore the limitation is met), and the hydrophilic polymer is contained in an amount of 1.0 parts by mass or more with respect to 100 parts by mass of the polyvinylidene fluoride-based resin (a polyhydric alcohol or a surfactant in a ratio of 50 mass % or less, see ¶44 which overlaps with the claimed range).
The examiner takes note of the fact that the prior art range of 50 mass % or less overlaps the claimed range of 1.0 mass % or more. Absent any additional and more specific information in the prior art, a prima facie case of obviousness exists. In re Peterson, 315 F.3d 1325, 1330, 65 USPQ2d 1379 (Fed. Cir. 2003). MPEP 2144.05.
Regarding claim 20, Iwai teaches the hollow fiber membrane according to claim 1, wherein the average diameter Dan of the spherical structure is gradually reduced from the average diameter Dai in a region Sai to an average diameter Daimin in a region Samin (D1 = 3.35 um, D2 = 3.11 um and D3 = 3.06 um, see comparative Example 3 in ¶183).
Allowable Subject Matter
Claims 5, 8-11 and 13 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include 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:
Regarding claim 5, Iwai teaches the hollow fiber membrane according to claim 1.
However, Iwai does not teach “wherein a relation of 1.00 ≤ Da1/Da2 ≤ 1.10 is satisfied” as required by claim 5.
It would not have been obvious to one of ordinary skill in the art before the effective filing date to modify Iwai to arrive at the claimed range because Iwai, in fact, teaches away from having
1.00 ≤ Da1/Da2 ≤ 1.10 as it is demonstrated in Comparative Example 1, separation membranes that fall within this range have low water permeation performance and readily causing elevation of filtration resistance (Iwai, see ¶179).
Regarding claim 13, Iwai teaches the membrane according to claim 12.
It is noted in the background of Iwai, that sodium hypochlorite is used for sterilizing permeate or preventing biofouling of the separation membrane (Iwai, see ¶4).
However, Iwai does not teach nor fairly suggest “wherein a percentage of a ratio P1/P0of P1 to P0 is 70% or less, where P1 is a ratio (mass%) of the hydrophilic polymer to the polyvinylidene fluoride-based resin after the hollow fiber membrane is immersed in a 3,000 ppm of aqueous sodium hypochlorite solution (pH 12.5) at 60oC for 30 hours, and PO is a ratio (mass%) of the hydrophilic polymer to the polyvinylidene fluoride-based resin before the immersion” as required by claim 13. There is no known benefit of incorporating the precise combination of elements to the separation membrane of Iwai.
Regarding claim 8, Iwai teaches the hollow fiber membrane according to claim 1.
However, Iwai does not teach nor fairly suggest “wherein when a throat diameter obtained by a pore network model analysis for the hollow fiber membrane is defined as a constriction diameter of a spherical structure gap, an average diameter dan of the constriction diameter of the spherical structure gap in the region San of 10 x (n - 1) to 10 x n um from the first surface, and an average diameter dbn of the constriction diameter of the spherical structure gap in the region Sbn of 10 x (n - 1) to 10 x n um from the second surface satisfy a relation of da1>db2, and a minimum value jmin of a natural number j satisfying the following conditions (1) and (2) satisfies a relation of 3 ≤ jmin ≤ (L - 20)/10, (1) da1/da2 ≥ 1.15 (2) da, - db2 ≤ 0.10 um provided that in the relation of 3 ≤ jmin ≤ (L - 20)/10, a decimal point or less of (L - 20)/10 is truncated” as required by claim 8. There is no known benefit of incorporating the precise combination of elements to the separation membrane of Iwai. Dependent claims 9-11 dependent from claim 8 therefore are also indicated allowable.
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 EKANDRA S. MILLER-CRUZ whose telephone number is (571)270-7849. The examiner can normally be reached M-Th 7 am - 6 pm EST.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Benjamin L. Lebron can be reached at (571) 272-0475. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/EKANDRA S. MILLER-CRUZ/Primary Examiner, Art Unit 1773
Prosecution Insights