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 .
SEPARATOR FOR AN ELECTRIC STORAGE DEVICE
Examiner: Adam Arciero S.N. 18/282,056 Art Unit: 1727 October 14, 2026
DETAILED ACTION
Applicant’s response filed on July 23, 2026 has been received. Claims 24-48 are currently pending. Claims 24, 36, 38, 41 and 44 have been amended.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim Rejections - 35 USC § 112
The claim rejections under 35 USC 112(b) on claims 24-35, 41-43 and 45-47 are withdrawn because Applicant has amended the claims.
Claim Rejections - 35 USC § 103
The claim rejections under 35 USC 103(a) as being unpatentable over Sugawara on claims 24-26, 30-44 and 46-48 are withdrawn because Applicant has amended the claims.
The claim rejections under 35 USC 103(a) as being unpatentable over Sugawara and Xiao on claims 27-29 and 45 are withdrawn because Applicant has amended the claims.
Claim(s) 24-29 and 30-48 is/are rejected under 35 U.S.C. 103 as being unpatentable over Sugawara (US 2017/0018749 A1; as found in IDS dated 07/21/24) in view of Xiao et al. (US 2019/0267599 A1; as found in IDS dated 10/16/25).
As to Claims 24-25, 30-31, 33, 35-37, 39-44, 47-48, Sugawara discloses a battery, comprising: a negative electrode; a positive electrode comprising LiFePO4; and a separator arranged therebetween (paragraphs [0099 and 0168]). Said separator comprises: a microporous membrane having a substrate, comprising: a first laminar polypropylene region (microporous layer (B)/second porous surface; and reads on containing more than 70 wt% PP) having a first average major pore diameter of 100-500 nm and a second laminar polypropylene region (microporous layer (A)/first porous surface; and reads on containing more than 70 wt% PP) adjacent the first laminar region and having an average major pore diameter larger than the first laminar region and from 250 nm to 1200 nm (Abstract and paragraphs [0003, 0021-0022, 0035 and 0042]). These ranges overlap with the claimed ratio. In addition, Sugawara teaches that the average pore diameter if a result-effective variable that can be appropriately adjusted to provide a separator with improved handling properties (paragraphs [0010 and 0040]). The courts have held that in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); and that a particular parameter must first be recognized as a result-effective variable, i.e., a variable which achieves a recognized result, before the determination of the optimum or workable ranges of said variable might be characterized as routine experimentation, see MPEP 2144.05, I, A and II, B. At the time of the invention, it would have been obvious to one of ordinary skill in the art to modify and optimize the separator of Sugawara to read on the claims because Sugawara teaches that a separator with improved handling properties and a battery with improved performance can be provided (paragraphs [0010 and 0040]). Sugawara does not specifically disclose the claimed melt flow rate relationship.
However, Xiao teaches of a separator that comprises three polypropylene microporous layers arranged in order, and wherein the MW of an outermost layer can be greater (which directly affects the melt flow rates of each layer such that they will read on the claimed relationship) (Abstract, Fig. 1, paragraphs [0111]). At the time of the invention, it would have been obvious to one of ordinary skill in the art to modify the separator of Sugawara to comprise the claimed relationship because Xiao teaches that a separator with improved puncture strength is provided (paragraph [0111]).
As to Claims 26, 32, 38, 42, 44, 46, Sugawara discloses the same separator as the claimed invention. It is the position of the Office that the separator of the prior art intrinsically has the claimed properties given that the structure and materials of the prior art and the claimed invention are the same, see MPEP 2112.
As to Claims 27-29 and 45, Sugawara does not specifically disclose the claimed microporous layer (C).
However, Xiao teaches of a separator that comprises three polypropylene microporous layers arranged in order, and wherein the average pore diameter ranges from 0.02-0.06 microns (Abstract, Fig. 1, paragraphs [0099-0100, 0114, and Table 2). At the time of the invention, it would have been obvious to one of ordinary skill in the art to modify the separator of Sugawara to comprise the claimed microporous PP layer (C) with the claimed average pore diameter ratios because Xiao teaches that a separator with improved dielectric break down and strength properties is provided (Abstract). In addition, the average pore diameter if a result-effective variable that can be appropriately adjusted to provide a separator with improved handling properties (paragraphs [0010 and 0040]). The courts have held that a particular parameter must first be recognized as a result-effective variable, i.e., a variable which achieves a recognized result, before the determination of the optimum or workable ranges of said variable might be characterized as routine experimentation, see MPEP 2144.05, I, A and II, B. At the time of the invention, it would have been obvious to one of ordinary skill in the art to modify and optimize the separator of modified Sugawara to read on the claims because Sugawara teaches that a separator with improved handling properties and a battery with improved performance can be provided (paragraphs [0010 and 0040]).
As to Claim 34, Sugawara does not specifically disclose that the second laminar region faces the negative electrode. However, there are a known finite number of options for arranging the claimed microporous layers and the courts have held that a person having ordinary skill int eh art would have good reason to pursue the known options within their technical grasp and if this leads to anticipated success, it is likely that the product is not of innovation but of ordinary skill and common sense, see KSR, MPEP 2143, I, E. At the time of the invention, it would have been obvious to one of ordinary skill in the art to modify the separator of Sugawara to read on the claims because Sugawara teaches that a separator with improved handling properties and a battery with improved performance can be provided (paragraphs [0010 and 0040]).
Response to Arguments
Applicant's arguments filed July 23, 2026 with respect to the independent claims have been fully considered but they are not persuasive.
Applicant’s principle arguments are:
a) Sugawara does not disclose or suggest controlling pore size by melt flow rate (claims 24, 36 and 41).
b) Sugawara is silent to the claimed melt flow rate relationship (claims 24, 36 and 41).
c) Sugawara does not teach of polypropylene and the working examples use polyimide/polyamide-imide resins (claims 24, 36 and 41).
d) the claimed pore diameter ratio provides for an unexpected result (claims 24, 36 and 41).
In response to Applicant’s arguments, please consider the following comments:
a) The claims are drawn to a product and not the process of making, see MPEP 2113.
b) Xiao teaches of the claimed relationship of melt flow rates through the differences in MW of each layer, as discussed in the rejection above.
c) Sugawara does teach of polypropylene and does not teach away from using polypropylene.
d) The results are not persuasive for at least the reason of the claims not being fully commensurate in scope with the results. In addition, there are no examples (such as 0.95) or comparative examples (such as 0.96) close to the limits of the claimed range. There is only data for PP amounts of 80, 95 and 100, not for 70 or more.
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 ADAM ARCIERO whose telephone number is (571)270-5116. The examiner can normally be reached Monday-Friday 8:00-5 ET.
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/ADAM A ARCIERO/ Primary Examiner, Art Unit 1727
