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 .
Election/Restrictions
Applicant’s election without traverse of claims 1-9 in the reply filed on 10/21/25 is acknowledged.
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.
Claim(s) 1, 5, 6 and 8 are rejected under 35 U.S.C. 103 as unpatentable over Lee et al, “Electrospun Polystyrene Nanofiber Membrane with Superhydrophobicity and Superoleophilicity for Selective Separation of Water and Low Viscous Oil”, 10597- ACS Appl. Mater. Interfaces 2013, 5, 10604
This reference is supplied by the applicant in an IDS. It teaches electrospun polystyrene nanofiber membrane for the express purpose of oil/water emulsion separation. It being super oleophilic, would inherently have the contact angle as claimed for oil as in claim 9. Pore size is inherently within the range claimed because of the following reasons: (1) fiber diameter of 317 nm, (2) porosity or void volume at 0.8613 cc/g, which is about 86% porosity (density of polystyrene is about 1 g/cc), (3) the SEMs appears to show the pore size between about 2.5 – about 30 microns. The 2.5 microns is the size of the “bead” in the red circles in fig. 2 (b), and the void spaces appear to be larger than this. The upper pore size is limited by the underlying SS mesh, which is disclosed as approximately 30 microns, and in the SEM, appears to be about 20 – 50 microns (by physically scaling). Therefore, the pore size would be within the range claimed or closely overlapping.
Fibers being electro-spun would have circular cross-section and would be crushed at the joints because the fibers are being thermally, or mechanically interconnected. “Crushed shape” is not a patentable invention unless otherwise shown. See MPEP 2144.04 about mere changes in shape.
In re Dailey, 357 F.2d 669, 149 USPQ 47 (CCPA 1966) (The court held that the configuration of the claimed disposable plastic nursing container was a matter of choice which a person of ordinary skill in the art would have found obvious absent persuasive evidence that the particular configuration of the claimed container was significant.).
Compressing or calendaring is only a process limitation, not patentable in the product claim. MPEP 2113.
Thickness: while the reference does not explicitly state the thickness, it does teach that the thickness is varied by the deposition time between 3 and 20 minutes. This would suggest a similar thickness range. Thickness is also a result-effective variable because higher thickness would result in lower flow rate.
Contact angles for water and oil are inherent material properties.
Claim(s) 1, 5, 6, and 8 are rejected under 35 U.S.C. 103 as unpatentable over DE 11015000874.
DE teaches a membrane having PVdF nanofibers, with pore size range 0.1-15 microns or 1-6 microns – overlapping range for claim 3. The element, compressed at 10-100 kPa is a process limitation, which is not patentable in a product claim. MPEP 2113. Thickness of nanofiber layer is 0.25 nm to 10 millimeters – overlapping range for claims 1 and 4. The actual thickness and pore size can be controlled and optimized for the desired use of such membranes and therefore is obvious, unless otherwise shown. DE teaches that this membrane can be of high surface area and porosity, but does not specify the porosity (void volume.) However, this is another result-effective variable that can be optimized based on pressure drop and flow rate required vs mechanical strength. It is also obvious to provide the highest porosity without compromising the mechanical strength to withstand the operating pressure. Membrane material is PVdF, polystyrene or other hydrophobic materials. The membrane being lipophilic, and the contact angle for the membrane (hydrophobicity) are inherent material properties of PVdF and polystyrene (evidence – see rejection 1.) See MPEP 2112 for inherency. Fibers being electro-spun would have circular cross-section and would be crushed at the joints because the fibers are being thermally, or mechanically interconnected.
Most details are in the running pages 9 and 10 of the reference. Unfortunately, the English translation affords no page and line numbers, but the cited terminology can be easily located by word search in the PDF file.
Arguments traversing this rejection are not persuasive.
The crushed shape (whether incidental or intentional) is merely a minor change in shape and would make no contribution to the membrane performance characteristics, unless otherwise shown with supporting evidence. The range of pore size is met by the reference because of the significant overlap, and does not have to meet the upper limit MPEP 2144.05-I. Optimizing a result-effective variable is prima facie obvious. MPEP 2144.05-II. There is no evidence for any criticality of pore size. Regarding uniform and dense pores, the term “dense pores” in the specification is an oxymoron; and the uniformity is unclear – the claimed range for the averages is very wide, compared to the teachings of the references.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KRISHNAN S MENON whose telephone number is (571)272-1143. The examiner can normally be reached Flexible, but generally Monday-Friday: 8:00AM-4:30PM.
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/KRISHNAN S MENON/ Primary Examiner, Art Unit 1777
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