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 is a first action on the merits of the application.
Claims 2, 11-12, and 20-26 are pending.
Election/Restrictions
Restriction to one of the following inventions is required under 35 U.S.C. 121:
I. Claims 1, and 3-10: directed to a flat sheet membrane and method of making the same, including depositing a polymer a solution on a support surface, controlling deposited thickness and support-surface temperature, coagulating the deposited layer, and removing the resulting flat-sheet membrane; CPC: B01D 69/06, B01D 69/061.
II. Claims 2, 11-12, and 20-26: directed to a hollow fiber membrane and method of making the same, including spinning a polymer solution through a nozzle into a coagulation bath and, in certain claims, employing an air gap, concentric bore/annulus nozzle geometry, post-coagulation heating, specified non-solvent/solvent systems, molecular weight, polymer concentration, dioxane concentration, and coagulation-bath temperature; CPC: B01D 69/08, B0D1 69/085, B01D69/087.
Claims 13-19 are canceled and therefore not subject to the present restriction requirement.
The inventions are distinct because invention I requires a flat-sheet casting architecture comprising deposition of polymer solution on a support surface, control of coating thickness, and control of support-surface temperature, whereas invention II requires hollow-fiber formation by spinning polymer solution through a nozzle into a coagulation bath, with hollow-fiber-specific process and nozzle features. The two inventions therefore involve materially different membrane-forming equipment, geometries, and process parameters.
A serious search and examination burden exists because examination of invention I requires searching a flat-sheet casting, support-surface temperature, coating thickness, and phase-inversion membrane, whereas examination of invention II requires searching hollow-fiber spinning, spinneret/nozzle geometry, air gap, bore-fluid, and hollow-fiber coagulation technology. Separate search strategies and materially different prior-art fields are therefore required. See MPEP 803, 806.05(j), and 808.02.
Restriction for examination purposes as indicated is proper because all the inventions listed in this action are independent or distinct for the reasons given above and there would be a serious search and/or examination burden if restrictions were not required because one or more of the following reasons apply:
(a) The inventions have acquired a separate status in the art in view of their different classification.
(b) The inventions have acquired a separate status in the art due to their recognized divergent subject matter.
(c) The inventions require a different field of search (for example searching for different classes/subclasses or electronic resources or employing different search queries).
(d) The inventions are likely to raise different non-prior art issues under 35 U.S.C. 101 and/or U.S.C. 112, first paragraph.
Applicant is advised that the reply to this requirement to be complete must include (i) an election of an invention to be examined even though the requirement may be traversed (37 CFR 1.143) and (ii) identification of the claims encompassing the elected invention.
The election of an invention may be made with or without traverse. To reserve a right to petition, the election must be made with traverse. If the reply does not distinctly and specifically point out supposed errors in the restriction requirement, the election shall be treated as an election without traverse. Traversal must be presented at the time of election in order to be considered timely. Failure to timely traverse the requirement will result in the loss of right to petition under 37 CFR 1.144. If claims are added after the election, applicant must indicate which of these claims are readable upon the elected invention.
Should applicants traverse on the ground that the inventions are not patentably distinct, applicant should submit evidence or identify such evidence now of record showing the inventions to be obvious variants or clearly admit on the record that this is the case. In either instance, if the examiner finds one of the inventions unpatentable over the prior art, the evidence or admission may be used in a rejection under 35 U.S.C. 103 or pre-AIA 35 U.S.C. 103(a) of the other invention.
During a telephone conversation with Llewellyn Rhys Lawson on September 2, 2026, a provisional election was made without traverse to prosecute the invention of Group II, claims 2, 11-12, and 20-26. Affirmation of this election must be made by applicant in replying to this Office action. Claims 1, and 3-10 are withdrawn from further consideration by the examiner, 37 CFR 1.142(b), as being drawn to a non-elected invention.
The examiner has required restrictions between product or apparatus claims and process claims. Where applicant elects claims directed to the product/apparatus, and all product/apparatus claims are subsequently found allowable, withdrawn process claims that include all the limitations of the allowable product/apparatus claims should be considered for rejoinder. All claims directed to a nonelected process invention must include all the limitations of an allowable product/apparatus claim for that process invention to be rejoined.
In the event of rejoinder, the requirement for restriction between the product/apparatus claims and the rejoined process claims will be withdrawn, and the rejoined process claims will be fully examined for patentability in accordance with 37 CFR 1.104. Thus, to be allowable, the rejoined claims must meet all criteria for patentability including the requirements of 35 U.S.C. 101, 102, 103 and 112. Until all claims to the elected product/apparatus are found allowable, an otherwise proper restriction requirement between product/apparatus claims and process claims may be maintained. Withdrawn process claims that are not commensurate in scope with an allowable product/apparatus claim will not be rejoined. See MPEP § 821.04. Additionally, in order for rejoinder to occur, applicant is advised that the process claims should be amended during prosecution to require the limitations of the product/apparatus claims. Failure to do so may result in no rejoinder. Further, note that the prohibition against double patenting rejections of 35 U.S.C. 121 does not apply where the restriction requirement is withdrawn by the examiner before the patent issues. See MPEP § 804.01.
Claim Objections
Claim 20 is objected to because of the following informalities:
(i) Claim 20 recites “heating the flat sheet membrane or the hollow fiber membrane,” whereas claim 20 depends solely on claim 2, which is directed only to making a hollow fiber membrane. It is respectfully suggested to amend the limitation by removing the “flat sheet membrane” from the claim limitation.
Appropriate correction is required.
Claim Rejections - 35 USC § 102
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.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
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 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.
Claims 2, 11-12, 21, 22, and 26 are rejected under 35 U.S.C. 102 as being anticipated by Duweg et al., (US 5,505,890, hereinafter as “Duweg).
Regarding claim 2, Duweg teaches a process for manufacturing a dialysis membrane in the form of a hollow fiber having a continuous internal cavity and made of cellulose acetate or a cellulose-acetate derivative (Abstract; col. 1, lines 10-13; col 2, lines 58-67). Duweg discloses a cellulose-acetate hollow fiber dialysis membrane, where the finished hollow fiber exhibits a measured dialytic permeability to urea (col. 5, lines 1-9). Duweg discloses a method of making a hollow fiber membrane selectively permeable to urea, comprising:
a spinning solution containing 9-20 wt% cellulose acetate and 42-91wt% acetic acid (col. 3, lines 32-34) (dissolving a polymer in one or more solvents into a polymer solution, wherein the polymer includes cellulose acetate).
the cellulose-acetate spinning solution is extruded through a spinneret suitable for manufacturing hollow fibers, specifically an annular slit nozzle, and the resulting spinning stream is introduced into a precipitation bath (col. 3, lines 8-18; col. 4, lines 44-51) (spinning the polymer solution via a nozzle into a coagulation bath), the extruded cellulose-acetate hollow fiber is precipitated in a dilute aqueous acetic acid bath, where the precipitation bath is maintained between 0oC and 16oC (col. 3, lines 15-23; col. 3, lines 19-21) (wherein the coagulation bath includes a nonsolvent to allow the polymer to coagulate into a hollow fiber membrane, wherein the coagulation bath is maintained at a temperature from 0 ºC to 22 ºC), the combined spinning stream passes through the precipitation bath to a depth of 85 cm and is returned to the surface by the deflecting roller; thereafter the formed hollow fiber is rinsed repeatedly to remove the solvent and accompanying substances, treated with glycerin, dried and wounds (col. 4, lines 56-67) (removing the hollow fiber membrane from the coagulation bath).
In regard to claim 11, Duweg teaches the spinneret is positioned 4 cm above the precipitation-bath surface and the spinning stream pass through the air gap before entering the gap (col. 4, lines 44-67) (spinning the polymer solution through an air gap between the nozzle and a surface of the coagulation bath).
In regard to claim 12, Duweg teaches the cellulose-acetate spinning solution is discharged through an annular slit nozzle while an internal filling fluid is supplied through the centrally located internal-filling feed into the forming hollow-fiber as it forms (col. 4, lines 44-55).
In regard to claim 21, Duweg teaches the coagulation/precipitation bath is dilute acetic acid in water (col. 3, lines 8-19) (the nonsolvent is water).
In regard to claim 22, Duweg teaches the acetic acid is used as the organic solvent in the cellulose acetate spinning solution (col. 3, lines 32-38) (the solvent includes one or more solvents from the group consisting of dioxane, acetone, acetic acid, methanol, and n-methyl-2-pyrrolidone).
In regard to claim 26, Duweg discloses a broader operative precipitation bath range of 0-16oC (col. 3, lines 19-20) (the coagulation bath temperature is about 0 ºC to about 5 ºC).
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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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.
Claim 20 is rejected under 35 USC 103 as being unpatented over Duweg, as applied to claim 2, and further in view of Su et al., (Cellulose acetate nanofiltration hollow fiber membranes for forward osmosis processes, Journal of Membrane Science, 2010, 355, pp. 36-44, hereinafter as “Su”).
Regarding claim 20, Duweg teaches a method of making a hollow fiber membrane selectively permeable to urea.
But Duweg does not disclose after the coagulation bath, heating the hollow fiber membrane at a temperature from 60 ºC to 80 ºC for about 45 minutes to about 120 minutes.
However, Su teaches heating a cellulose hollow-fiber membrane at 60 ºC for about 60 minutes, which falls directly within both claim ranges (Abstract; p. 37, Heat-treatment of the cellulose acetate hollow fiber membranes, first paragraph, lines 1-5).
Duweg and Su are analogous arts because both are directed to cellulose-acetate semi-permeable hollow-fiber membranes and their fabrication.
Therefore, before the effective filing date of the claimed invention, it would have been prima facie obvious to one of ordinary skill in the art to heat-treat Duweg’s cellulose-acetate hollow fiber at 60 ºC for about 60 minutes as taught by Su because the heat treatment effectively shrinks the membrane mean pore radius, affecting pore radius and outer-skin-layer thickness thereby providing a known means for modifying the pore/selective-layer structure of a cellulose-acetate hollow fiber, predictably controlling membrane separation properties (Su: Abstract; p. 43, Conclusion, left column, lines 1-16).
Claims 23 and 25 are rejected under 35 USC 103 as being unpatented over Duweg, as applied to claim 2, and further in view of Nguyen et al., (Preparation of cellulose triacetate/cellulose acetate (CTA/CA)-based membranes for forward analysis, Journal of Membrane Science 433, pp. 49-59, hereinafter as “Nguyen”).
In regard to claim 23, Duweg teaches a method of making a hollow fiber membrane selectively permeable to urea.
But Duweg does not disclose the cellulose acetate has a number average molecular weight (Mn) of about 30,000.
However, Nguyen teaches cellulose acetate having an average molecular weight (Mn) of approximately an Mn of 30,000 for preparing semi-permeable cellulose-acetate-containing membrane by immersion precipitation (p. 50, 2.1. Materials, left column, first paragraph, lines 1-3), which meets the claim limitation, “wherein the cellulose acetate has a number average molecular weight (Mn) of about 30,000.”
Duweg and Nguyen are analogous arts because both are directed to fabrication of semipermeable cellulose-acetate membrane from cellulose-acetate/solvent solutions by nonsolvent-induced phase separation.
Therefore, before the effective filing date of the claimed invention, it would have been prima facie obvious to one of ordinary skill in the art to use Nguyen’s Mn of about 30,0000 cellulose acetate in Duweg’s cellulose-acetate spinning solution because that molecular weight of the cellulose acetate is an operative membrane-forming polymer for phase-inversion fabrication, providing a known and predictable cellulose-acetate material for producing a semipermeable membrane having a higher water flux and salt resistance than the commercial membranes (Nguyen: Abstract; p. 58, Conclusions, left column, first paragraph, lines 1-4).
In regard to claim 25, Duweg discloses a preferred spinning solution range of 10-15% cellulose acetate wt% (col. 3, lines 35-37), encompassing the claimed range from about 14 wt% to about 15 wt% cellulose acetate. Nguyen teaches a polymer solution including 49.9 wt% 1,4-dioxane (p. 50, 2.2. Preparation of flat-sheet CTA/CA-based membranes, right column, second paragraph, line 9) which meets the limitation, “at least 45 wt% dioxane.”
Claim 24 is rejected under 35 USC 103 as being unpatented over Duweg, as applied to claim 2, and further in view of Dunweg et al., (US 5403485, hereinafter as Dunweg).
In regard to claim 24, Duweg teaches a method of making a hollow fiber membrane selectively permeable to urea.
But Duweg does not disclose wherein the polymer solution includes about 30 wt% to about 40 wt% of cellulose acetate.
However, Dunweg teaches a spinning solution containing 9-30% cellulose acetate (col. 3, lines 59-60). Since the claimed polymer solution includes range of about 30 wt% to about 40 wt% of cellulose acetate overlaps the polymer solution includes range of about 30 wt% as taught by Dunweg, the range recited in claim 24 is considered prima facie obvious. See MPEP 2144.05.
Duweg and Dunweg are analogous arts because both are directed to the same field of endeavor: manufacturing cellulose acetate hollow-fiber dialysis membranes using cellulose acetate spinning solutions and precipitation.
Therefore, before the effective filing date of the claimed invention, it would have been prima facie obvious to one of ordinary skill in the art to employ the 30% wt% cellulose-acetate concentration taught by Dunweg in Duweg’s cellulose-acetate spinning solution because that particular wt% cellulose-acetate concentration selection produce an optimal permeability ranges of the hollow-fiber dialysis membrane (Dunweg: col. 3, lines 3-10).
Conclusion
Any inquiry concerning this communication or earlier communication from the examiner should be directed to Wilson Mendoza whose telephone number is (571) 272-8443. The examiner can normally be reached on Monday – Friday from 9:00 AM until 5:00 PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, In Suk Bullock can be reached on 571-272-5954. The fax phone number for the organization where this application or processing is assigned is 571-273-8300.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, In Suk Bullock can be reached on 571-272-5954. The fax phone number for the organization where this application or processing is assigned is 571-273-8300.
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/WILSON GALLARDO MENDOZA/Examiner, Art Unit 1772
/IN SUK C BULLOCK/Supervisory Patent Examiner, Art Unit 1772
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