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 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, 5-6, 9, and 12-19 are rejected under 35 U.S.C. 103 as being unpatentable over Araki et al. (EP 3343671 A1, published 4 July 2018) in view of Kusakabe et al. (US 20190051878 A1, published 14 Feb 2019).
Regarding claim 1, Araki et al. discloses a lead storage battery, comprising: a positive electrode (10); a negative electrode (20); a separator (30) interposed between the positive electrode and the negative electrode; and a nonwoven fabric (second porous sheet 50, [0047-0048]) that is arranged between the negative electrode and the separator ([0041]), and comprises fibers and a filler (where the filler is an inorganic power [0045-0048]). While Araki teaches that the nonwoven fabric is arranged between the negative electrode and the separator, Araki also discloses that the separator may alternatively accommodate the positive electrode ([0040]). Thus, it would have been obvious to one of ordinary skill in the art to arrange the nonwoven fabric between the positive electrode and the separator.
Furthermore, Araki teaches that the separator comprises ribs (42, 43, [0053-0055]) each formed in a convex shape from a base portion on the side of the negative electrode, and a thickness T of the nonwoven fabric (0.3 mm or less, [0072]) and a height R from the base portion taken as a reference point to a top of the ribs (preferably 0.3 mm or more and 1.25 mm or less, [0068]) have a relationship T/R of 1.0 or more and 3.0 or less (in Araki et al., T/R is 1.0 when T is 0.3 mm and R is 0.3 mm). Araki also discloses that the lower base width (A) of the ribs is preferably 0.4 mm to 1 mm, due to high shape retention of the rib ([0071]; Fig. 2b), and teaches that interval between ribs is between 3 mm and 15 mm ([0053]; Fig. 2a). Figure 2a further shows that the ribs extend the length of the separator, so the ratio of rib area to total area will be dependent on the width.
It would have been obvious to one of ordinary skill in the art to optimize A/(A+B), wherein the area of convex portions (ribs) is defined as A and the area of the base portion is defined as B in an effective range of the separator in a plan view (such as in Fig. 2a), to within a range of 0.06 to 0.15. Araki identifies that the width of the ribs is results effective, as it impacts the ribs’ shape retention. 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 MPEP § 2144.05, II.).
The examiner also notes that Example 1A ([0129]) appears to meet the claimed ratio of A/(A+B) when the mini ribs are excluded. In the case where there are 8 ribs, the rib width is 0.8 mm, the rib interval is 9.8 mm, and there is a total of 9 intervals, such that none of ribs are along the edge of the region, A would be equivalent to 6.4 mm (total rib width), B would be 88.2 mm (total width of the intervals between ribs), and A/(A+B) would be approximately 0.68, which is within the claimed range of 0.06 to 0.15.
Araki further discloses that the thickness of the nonwoven fabric is preferably 0.3 mm or less ([0072]), which is equivalent to 300 µm or less, and therefore outside the claimed range of 410 µm to 1200 µm. Araki teaches that this range is preferred because it reduces charge transfer resistance ([0072]).
However, Kusakabe et al. discloses a nonwoven fabric separator comprising synthetic fibers such as polyacrylonitrile or polystyrene fibers ([0049-0051]), and teaches a coated nonwoven separator embodiment which comprises inorganic particles ([0086]) that fill the pores of the fabric ([0113]). Kusakabe further discloses that the nonwoven fabric separator has a thickness of preferably from 30 to 1000 μm ([0076]), and the coated embodiment has a thickness of preferably from 10 to 5000 μm ([0115]). Kusakabe teaches that above this range resistance is increased and the number of cells is decreased, thereby reducing capacity, and below this range, the fabric cannot withstand the movement of an active material during electrode reaction, causing short circuit ([0115]).
It would have been obvious to one of ordinary skill in the art to increase the thickness of the nonwoven fabric of Araki to between 410 µm and 1000 µm, as Kusakabe teaches that electrical resistance is not substantially increased (which is the primary concern of Araki) until the thickness of a nonwoven fabric is greater than 1000 μm, and in some embodiments, greater than 5000 μm. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists (see MPEP § 2144.05). Furthermore, one of ordinary skill in the art would still be able to achieve a relationship T/R of 1.0 or more and 3.0 or less, given that Araki teaches a preferrable rib height range of 0.3 mm (300 µm) to 1.25 mm (1250 µm). 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 MPEP § 2144.05, II.).
Araki further discloses that the nonwoven fabric (second porous sheet) has a mean flow pore size of 1 µm to 200 µm ([0012]). Araki teaches that this range is preferred because it enables sufficient permeation of ions and improve charge acceptance performance ([0052]). This meets the lower limit of the claimed range, which requires the pore size to be 0.05 µm or larger, but is greater than the upper limit of 0.78 µm or smaller, and thus does not meet the claim limitations.
Kusakabe further discloses that the nonwoven fabric separator has an average pore diameter of preferably from 0.1 to 50 μm ([0074]), and the coated embodiment has an average pore diameter of preferably from 0.1 to 200 μm ([0114]). Kusakabe teaches that above this range, pin holes form, thus inducing short circuit, and below this range, ion conductivity is reduced and resistance increased ([0114]).
It would have been obvious to one of ordinary skill in the art to decrease the mean flow pore size of the nonwoven fabric of Araki to between 0.1 µm and 0.78 µm, as Kusakabe teaches that ion conductivity is not substantially decreased (which is related to Araki’s primary concern of ion permeation) until the pore size of a nonwoven fabric is less than 0.1 μm. Thus, one of ordinary skill in the art would expect predictable results even when the pore size of Araki is reduced. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists (see MPEP § 2144.05). Therefore, modified Araki et al. meets the limitations of claim 1.
Regarding claim 5, modified Araki et al. meets the limitations of claim 1 as discussed above. Kusakabe further teaches an example (EX. 22) which achieves a maximum pore size of 3.8 µm (see Table 2). While the average pore size of this example is 1.0 μm, which is greater than the claimed range of 0.05 µm and 0.78 µm, Kusakabe further teaches that the maximum pore diameter is dependent on the pressure at which the liquid film of the largest pore is broken, and the surface tension of the liquid ([0150-0154]). Therefore, the surface tension of the liquid chosen, in this case the electrolytic solution, is a results effective variable.
It would have been obvious to one of ordinary skill in the art that the maximum pore size of modified Araki could be less than 3.87 µm, as shown by example 22 of Kusakabe, while maintaining a mean flow pore size between 0.1 µm and 0.78 µm. The surface tension of the electrolytic solution is a results effective variable, and thus it would have been obvious to one of ordinary skill in the art to optimize the surface tension (by varying the composition of the electrolytic solution), so that both the mean flow pore size between 0.1 µm and 0.78 µm can be maintained and a maximum pore size of less than 3.87 µm can be achieved. 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. Furthermore, the discovery of an optimum value of a known result effective variable, without producing any new or unexpected results, is within the ambit of a person of ordinary skill in the art (see MPEP § 2144.05, II.). Therefore, modified Araki meets the limitations of claim 5.
Regarding claim 6, modified Araki et al. meets the limitations of claim 1 as discussed above. The maximum pore sizes in examples 1-47 (see Tables 2 and 5) provided by Kusakabe are all greater than 0.5 µm, so any maximum pore size selected from the examples taught by Kusakabe is within the claimed range. Therefore, modified Araki meets the limitations of claim 6.
Regarding claim 9, modified Araki et al. meets the limitations of claim 1 as discussed above. Araki does not disclose that the nonwoven fabric comprises an acrylic resin or a styrene resin. However, Araki discloses a material for the electrolytic cell which may comprise an ABS (acrylonitrile butadiene styrene) resin ([0125]). Araki further teaches that ABS resin has advantageous resistance against the electrolyte solution ([0125]).
It would have been obvious to one of ordinary skill in the art for the nonwoven fabric of Araki to comprise an ABS resin so that it is resistant to the electrolyte solution. The combination of familiar elements is likely to be obvious when it does no more than yield predictable results (see MPEP § 2143, A.). Furthermore, the selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art (see MPEP § 2144.07). Therefore, modified Araki meets the limitations of claim 9.
Regarding claim 12, modified Araki et al. meets the limitations of claim 1 as discussed above. Araki further discloses that the separator is porous, and comprises projected ribs (42, 43), which may be linear ([0053]). Therefore, modified Araki meets the limitations of claim 12.
Regarding claim 13, modified Araki et al. meets the limitations of claim 1 as discussed above. Araki further discloses that the separator is bag-like, and houses the positive electrode or the negative electrode ([0028-0032]; Figs. 1, 4). The examiner interprets the “bag-like” structure as meeting the claimed “envelope.” Therefore, modified Araki meets the limitations of claim 13.
Regarding claim 14, modified Araki et al. meets the limitations of claim 1 as discussed above. Araki further discloses that the separator accommodates the negative electrode ([0031-0032]). Therefore, modified Araki meets the limitations of claim 14.
Regarding claim 15, modified Araki et al. meets the limitations of claim 1 as discussed above. Araki further discloses that the separator may alternatively accommodate the positive electrode ([0040]). Therefore, modified Araki meets the limitations of claim 15.
Regarding claim 16, modified Araki et al. meets the limitations of claim 1 as discussed above. Araki further discloses that the fibers may comprise organic fibers such as polyolefin fibers ([0045-0046]). Therefore, modified Araki meets the limitations of claim 16.
Regarding claim 17, modified Araki et al. meets the limitations of claim 1 as discussed above. Araki further discloses that the filler comprises may comprise inorganic oxide powder ([0047]). Therefore, modified Araki meets the limitations of claim 17.
Regarding claim 18, modified Araki et al. meets the limitations of claim 1 as discussed above. Araki further discloses that the nonwoven fabric may comprises organic fibers and glass fibers as well as the inorganic oxide ([0045-0046]). Therefore, modified Araki meets the limitations of claim 18.
Regarding claim 19, modified Araki et al. meets the limitations of claim 1 as discussed above. Araki shows in figure 3 that the relationship T/R is more than 1, as the rib height is shown to be greater than the thickness of the fabric (paragraph 0069 teaches that the H/T ratio should be greater than .5, which provides a value of T/R within the range claimed). Furthermore, one of ordinary skill in the art would be able to achieve a relationship T/R of more than 1 by utilizing the preferrable rib height range of 0.3 mm (300 µm) to 1.25 mm (1250 µm) taught by Araki and the preferred thickness range of 30 to 1000 μm taught by Kusakabe, as discussed above regarding claim 1. 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 MPEP § 2144.05, II.). Therefore, modified Araki meets the limitations of claim 19.
Claims 10 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Araki et al. (EP 3343671 A1) in view of Kusakabe et al. (US 20190051878 A1) as applied to claims 1, 5-6, 9, and 12-19 above, and further in view of Hennige et al. (WO 03072231 A2, published 4 Sept 2003, pages cited from the provided English translation).
Regarding claim 10, modified Araki et al. meets the limitations of claim 9 as discussed above. Araki does not disclose that the acrylic resin or styrene resin comprises a silane compound. Hennige et al. discloses a membrane which comprises a nonwoven material (pg. 4). Hennige further teaches that it may be advantageous if the polymer fibers are bonded via adhesion promoters such as organofunctional silanes (pg. 4, L165-169).
It would have been obvious to one of ordinary skill in the art for the resin of modified Araki to comprise a silane compound, as taught by Hennige to promote adhesion of the fibers and filler included in the nonwoven fabric of Araki. The combination of familiar elements is likely to be obvious when it does no more than yield predictable results (see MPEP § 2143, A.). Furthermore, the selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art (see MPEP § 2144.07). Therefore, modified Araki meets the limitations of claim 10.
Regarding claim 11, modified Araki et al. meets the limitations of claim 10 as discussed above. Hennige teaches that the content of silicon (Si) in the silane compound is more than 0 parts by weight but 6 parts by weight or less with respect to 100 parts by weight of the acrylic resin and/or the styrene resin because Hennige teaches that the silane adhesion promotor should be included in an amount of 10% or less (and silicon is a component of the silane), thereby overlapping with the range claimed.
Response to Arguments
Applicant’s arguments with respect to claims 1,5-6 and 9-19 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument. Kusakabe et al. has been added to the rejections of claims 1 and 5 to address the amended limitations.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALEXANDRA J SIMMONS whose telephone number is (571)272-3036. The examiner can normally be reached M-F: 9:30a - 6p.
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/A.J.S./Examiner, Art Unit 1728
/MATTHEW T MARTIN/Supervisory Patent Examiner, Art Unit 1728
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