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 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 1-5, 7-9, 11-13, 15-17 and 19-20 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.
Claim 1 recites, “wherein the coating comprises first particles comprising primary particles and second particles comprising secondary particles” (emphasis added). Examiner notes that the term “primary particle” and the term “secondary particle” both have a known meaning in the art as evidenced by Sun et al. (US-20140158932-A1; see Abstract). Specifically, primary particles are known to refer to individual particles while secondary particles are known to refer to an aggregation of primary particles. Therefore, absent a special definition in the instant specification, it is unclear whether the recitation of “secondary particles” in Claim 1 refers to an agglomeration of primary particles, or whether the “primary particles” and “secondary particles” of Claim 1 are intended to refer to first particles and second particles, respectively. Accordingly, Claim 1 and dependent Claims 2-5, 7-9, 11-13, 15-17 and 19-20 are rejected as being indefinite. For the sake of compact prosecution, the second interpretation will be applied to the claims, as appears to be supported by the instant specification [instant specification: 0086, 00238], and the term “primary particles” will be interpreted as “first particles” and the term “secondary particles” will be interpreted as “second particles” (e.g. “wherein the coating comprises first particles and second particles, the second particles having a pore structure…”).
Claim 11 recites the limitation “the silicone particles”. Here it is unclear if the recitation of “the silicone particles” has sufficient antecedent basis, since Claim 1 (from which Claim 11 depends) recites silicone particles as a possible identity of the primary particles. It could be interpreted that Claim 11 is intended to further limit the identity of the primary particles in Claim 1 to silicone particles. Alternatively, it could be interpreted that this claim merely limits an optional limitation of Claim 1, and therefore is not afforded patentable weight if the optional limitation is selected (i.e. if the primary particles of Claim 1 are not silicone particles, Claim 11 would not be afforded patentable weight). As such, Claim 11 and dependent Claims 12-13 and 15-16 are rejected as being indefinite. Since the instant specification indicates that silicone particles can be used as the primary particles of the coating (see Examples 1-1 to 1-7 in Table 1; [00266-00267]), but are not required to be used as the primary particles of the coating (see Examples 1-8 to 1-9 in Table 1; [00266-00267]), for the sake of compact prosecution either interpretation will be applied to Claim 11.
Claim Rejections - 35 USC § 103
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(s) 1, 3-4, 8-16 and 19-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Seo et al. (US-20070122716-A1; previously cited) in view of Tanaka et al. (US-20180053963-A1; previously cited) and in view of Kajita et al. (US-20130059192-A1) and as evidenced by Kawakami et al. (US-20140377630-A1), as evidenced by Lee et al. (US-20110027642-A1), as evidenced by Hony Engineering Plastics Limited (hereinafter HONY; “Dielectric Constants of Commonly Used Polymer Plastics”; see attached NPL for citations), as evidenced by Yen et al. (US-20220311097-A1), and as further evidenced by ChemEurope.com Encyclopedia (hereinafter ChemEurope; “Hildebrand solubility parameter”; see attached NPL for citations).
Regarding Claim 1, Seo discloses a separator comprising a substrate (porous substrate) and a coating (organic/inorganic composite layer) provided on at least one side of the substrate ([0003, 0023-0024, 0074]; see Fig. 2). The coating (organic/inorganic composite layer) comprises a binder polymer and inorganic particles with a pore structure [0023-0024].
Seo discloses that the binder polymer is an organic binder polymer [0053]. Although Seo does not explicitly teach that the binder polymer is provided in the form of “particles”, Tanaka teaches that similar binder polymers are provided as organic particles [Tanaka: 0061, 0101], and that these organic particles are able to successfully provide adhesion when applied to a separator coating (functional layer) comprising inorganic particles [Tanaka: 0010, 0013]. Since Seo also desires adhesion in the coating [Seo: 0080], it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have provided the binder polymer of Seo as organic particles with a reasonable expectation that such a form of binder polymer would result in a successful coating with sufficient adhesion. The binder polymer reads on first particles.
The inorganic particles disclosed by Seo read on second particles comprising secondary particles having a pore structure (see Fig. 2; [0024, 0083, 0091, 0093]).
Seo discloses various non-limiting examples of the first particles (binder polymer) including polyacrylonitrile, acrylonitrile-styrene-butadiene copolymer, polyvinyl acetate, carboxymethyl cellulose, and polyimide [0053]. Seo discloses that other materials may be used so long as they satisfy the “above characteristics” [0053]. The above characteristics include a polymer which (1) does not melt in an electrolyte [0049], (2) has a glass transition temperature between -200 °C and 200 °C [0050], (3) has a dielectric constant in a range of 1 to 100 [0051], and (4) has a solubility parameter between 15 and 45 MPa1/2 [0052].
Kajita teaches a similar separator including a substrate (i.e. base layer 2, Fig. 1) and a coating (i.e. surface layer 3, Fig. 1) [0065]. The coating (surface layer) includes similar resin materials and similar inorganic particle materials [0080, 0113-0114] as the primary and secondary particle materials of modified Seo.
Kajita teaches that the resin material (corresponds to primary particles) can be selected from a group of materials which include polyacrylonitrile, acrylonitrile--butadiene-styrene copolymer, polyvinyl acetate, carboxymethyl cellulose, polyimide and polysulfone [0113]. These materials can be used alone or in a mixture of two or more [0113].
Furthermore, polysulfone: (1) does not melt in an electrolyte as evidenced by Kajita and Kawakami [Kajita: 0113]; [Kawakami: 0040], (2) has a glass transition temperature between -200 °C and 200 °C as evidenced by Lee [Lee: 0105], (3) has a dielectric constant in a range of 1 to 100 as evidenced by HONY (HONY: Pg. 2), and (4) has a solubility parameter between 15 and 45 MPa1/2 as evidenced by Yen and ChemEurope [Yen: 0177]; (see conversion between cal1/2•cm3/2 to MPa1/2; ChemEurope: Pg. 2).
Therefore, one of ordinary skill in the art, before the effective filing date of the claimed invention, would have found it obvious to have used polysulfone particles as the binder polymer of Seo with a reasonable expectation that the use of polysulfone particles would result in a successful coating for a separator (MPEP 2144.06, I-II; MPEP 2144.07). Polysulfone particles are within the list of claimed materials for the primary particles.
Seo discloses that the mixing ratio of secondary particles (inorganic particles) to primary particles (binder polymer of polysulfone particles) is from 50%:50% to 97%:3% by weight [Claim 10]. Although Seo does not teach that a ratio of a weight proportion A of the primary particles and a weight proportion B of the secondary particles satisfies 1<A/B≤20, Examiner notes that the disclosed range of 1 (i.e. 50%:50%) is so close to the lower limit of the claimed range (i.e. greater than 1) that that one of ordinary skill in the art would have expected a coating formed with a ratio of A/B of 1 to exhibit the same properties as a coating formed with a ratio of A/B of slightly greater than 1 (e.g. 1.0001), thereby establishing a prima facie case of obviousness (MPEP 2144.05, I).
Furthermore, Seo discloses that if the content of secondary particles (inorganic particles) is too low, the content of primary particles (binder polymer of polysulfone particles) becomes such that the interstitial volume formed among the secondary particles (inorganic particles) is decreased and battery quality is degraded [0047]. Meanwhile, if the content of the secondary particles (inorganic particles) is too high, sufficient adhesion is not achieved and the mechanical properties of the coating is degraded [0037].
Therefore, although Seo does not teach that a ratio of a weight proportion A of the primary particles and a weight proportion B of the secondary particles satisfies 1<A/B≤20, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have optimized the content of primary particles to secondary particles, including selecting the ratio of primary particles to secondary particles to be slightly larger than 1, with a reasonable expectation that such a ratio of primary particles to secondary particles would achieve a successful balance between battery quality and adhesion / mechanical strength (MPEP 2144.05, II).
Regarding Claim 3, modified Seo renders obvious all of the limitations as set forth above. Seo broadly discloses that the porosity of the secondary particles (inorganic particles) is between 30 to 95% [0037]. Therefore, although Seo does not explicitly teach that the porosity of the secondary particles (inorganic particles) is 10% to 60%, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have selected the overlapping portion of the range disclosed in the prior art with a reasonable expectation that such a porosity would result in successful secondary particles with sufficient battery performance and strength (MPEP 2144.05, I).
Furthermore, Seo discloses that if the porosity of the secondary particles (inorganic particles) is below 30%, the improvement of battery performance becomes difficult, while if the porosity exceeds 95%, the mechanical strength of the particle itself is weakened [0037].
Since Seo desires the secondary particles (inorganic particles) to be porous in order to decrease the weight of the battery and improve the energy density of a device [0023], and since Seo discloses that increasing the porosity of the secondary particles (inorganic particles) results in increased in battery performance at the expense of mechanical strength [0037], one of ordinary skill in the art, before the effective filing date of the claimed invention, would have found it obvious to have optimized the porosity of the secondary particles, including selecting the porosity of the secondary particles to be 30% to 60%, in order to strike a balance between energy density and mechanical strength (MPEP 2144.05, II).
Regarding Claim 4, modified Seo renders obvious all of the limitations as set forth above. Seo further discloses specific embodiments (Example 1, Example 3, Example 5) wherein the average particle size of the secondary particles (inorganic particles) is 400 nm [0083, 0091, 0093], thereby rendering obvious / disclosing with sufficient specificity secondary particles with an average particle size of 400 nm, which is within the claimed range of “less than or equal to 2 µm”.
Regarding Claim 8, modified Seo renders obvious all of the limitations as set forth above. Seo discloses that the secondary particles are inorganic particles [0023-0024]. In specific embodiments (Example 3, Example 5) the inorganic particles are TiO2 [0091, 0093], thereby rendering obvious / disclosing with sufficient specificity inorganic particles of TiO2, which is within the claimed list of inorganic particles (TiO2 is a form of “titanium oxides”).
Regarding Claim 9, modified Seo renders obvious all of the limitations as set forth above. Seo discloses that the secondary particles have a through-hole structure (see Figs. 2, 8; [0033]).
Regarding Claims 11-13 and 15-16, modified Seo renders obvious all of the limitations as set forth above, including that the primary particles comprise polysulfone (see rejection of Claim 1, above). The broadest reasonable interpretation of Claim 1 has silicone particles claimed in the alternative. Since Claim 11 recites “the silicone particles” and therefore appears to only limit previously present silicone particles, Claim 11 is interpreted as serving to further narrow an alternative limitation which is not required. Therefore, by including the claimed “polysulfone particles” modified Seo, under broadest reasonable interpretation, meets the limitations of Claim 11 and dependent Claims 12-13 and 15 (see 112(b) rejection, above). Seo discloses a specific embodiment (Example 1) wherein the porosity of the substrate (polyethylene film) is 45% [0083], which is within the claimed range of “greater than or equal to 25%” required by Claim 16.
Regarding Claim 19, modified Seo renders obvious all of the limitations as set forth above. Seo discloses a secondary battery comprising the separator according to claim 1 [0012-0013].
Regarding Claim 20, modified Seo renders obvious all of the limitations as set forth above. Seo discloses that batteries, particularly secondary batteries, are widely used as energy sources in portable phones, camcorders, notebook computers, PCs, and electric cars [0005]. Therefore, although Seo does not explicitly teach an “electric apparatus comprising the secondary battery according to claim 19”, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have provided an electric apparatus such as a portable phone, camcorder, notebook computer, PC, or electric car which uses disclosed secondary battery of Claim 19, with a reasonable expectation that the secondary battery would be able to successfully power the electric apparatus, thereby resulting in a successful electric apparatus.
Claim(s) 2 and 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Seo et al. (US-20070122716-A1; previously cited) in view of Tanaka et al. (US-20180053963-A1; previously cited) and in view of Kajita et al. (US-20130059192-A1) and as evidenced by Kawakami et al. (US-20140377630-A1), as evidenced by Lee et al. (US-20110027642-A1), as evidenced by Hony Engineering Plastics Limited (hereinafter HONY; “Dielectric Constants of Commonly Used Polymer Plastics”; see attached NPL for citations), as evidenced by Yen et al. (US-20220311097-A1), and as further evidenced by ChemEurope.com Encyclopedia (hereinafter ChemEurope; “Hildebrand solubility parameter”; see attached NPL for citations, as applied to Claim 1, above, and in further view of Yun et al. (US-20200203694-A1; previously cited).
Regarding Claim 2, modified Seo renders obvious all of the limitations as set forth above. Seo discloses that lithium ions can be solvated by electrolyte molecules (e.g. carbonated based compounds), and therefore it is important to take both the size of a lithium ion and the size of an electrolyte molecule into consideration [0031-0032]. Seo also discloses that the secondary particles (inorganic particles) have a size of 0.001 µm to 10 µm [0045]. Therefore, although Seo discloses that the inorganic porous particles have a number of macropores [0023], Examiner notes that the broad disclosure of Seo does not teach away from a smaller pore size, so long as the lithium ion size and the electrolyte molecule size are taken into consideration (MPEP 2123, I-II). Seo does not teach that the average pore size of the secondary particles is 0.1 nm to 10 nm.
Yun teaches a similar separator comprising a substrate coated with inorganic particles and a binder polymer [0006-0007]. The inorganic particles can be porous inorganic particles [0068]. Yun teaches that the porous inorganic particles may have a pore size of 1 -50 nm, and that such a pore size allows both for electrolyte holding and for HF or moisture to be isolated in the pores, thus aiding in smooth charge/discharge [0068].
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have included porous inorganic particles (secondary particles) with a pore size of 1-50 nm (i.e. a micropore) into the coating of Seo with a reasonable expectation that the addition of secondary particles with such a pore size would result in smooth charge/discharge and secondary particles which can isolate HF / moisture in the pores while allowing for electrolyte holding.
Although modified Seo does not teach that the average pore size is 0.1 nm to 10 nm, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have optimized the content of secondary particles with a macropore structure and the content of secondary particles with a micropore structure in order to strike a balance between the reduced weight provided by secondary particles with a macropore structure [Seo: 0034] and the smooth charge/discharge and isolation of HF / moisture provided by secondary particles with a micropore structure [Yun: 0068], including selecting contents of each which result in secondary particles with an average pore size which falls within the claimed range (MPEP 2144.05, II).
Regarding Claim 7, modified Seo renders obvious all of the limitations as set forth above. Seo discloses that the coating (organic/inorganic composite layer) can be applied to both sides of a porous separator substrate (see Fig. 2). Seo discloses that the secondary particles (inorganic porous particles) reduce the weight of the battery, leading to an increase in energy density per unit weight of the battery [0034], and are preferably provided in an amount of 50% to 97% in relation to the content of primary particles (binder polymer) [0047]. Such a content of secondary particles ensures mechanical properties while preventing an excessive amount of primary particles (binder polymer) from decreasing the porosity and degrading of the quality of the battery [0047]. In other words, Seo discloses that the content of secondary particles (inorganic porous particles) is not critical as long as the content of primary particles (binder polymer) is within an appropriate range to ensure adhesion, and so long as sufficient mechanical properties are ensured [0047]. Seo further discloses that the coating (organic/inorganic composite layer) may include other additives [0054]. Seo does not teach that the weight proportion of the secondary particles in the coating is less than or equal to 20%.
Yun teaches a similar separator comprising a substrate coated with inorganic particles and a binder polymer [0006-0007]. Yun teaches that a coating layer (second coating layer) can comprise a binder polymer [0055] and a combination of non-porous inorganic particles and porous inorganic particles (corresponds to secondary particles) [0068]. The binder polymer allows the second coating layer to act as an electrolyte reservoir [0056]. Advantageously, the non-porous inorganic particles improve the heat resistance and mechanical properties of the separator [0056].
Therefore, one of ordinary skill in the art, before the effective filing date of the claimed invention, would have found it obvious to have included non-porous inorganic particles as taught by Yun into the primary and secondary particles taught by Seo for the benefit of improving the heat resistance and mechanical properties of the separator while simultaneously optimizing the relative contents of each of these three components so as to arrive at the claimed content of secondary particles (i.e. “less than or equal to 20%”) in order to achieve a desired balance between improved the heat resistance and mechanical properties, improved electrolyte retention and adequate adhesion to the electrode, and increased energy density per unit weight of the battery (MPEP 2144.05, II).
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Seo et al. (US-20070122716-A1; previously cited) in view of Tanaka et al. (US-20180053963-A1; previously cited) and in view of Kajita et al. (US-20130059192-A1) and as evidenced by Kawakami et al. (US-20140377630-A1), as evidenced by Lee et al. (US-20110027642-A1), as evidenced by Hony Engineering Plastics Limited (hereinafter HONY; “Dielectric Constants of Commonly Used Polymer Plastics”; see attached NPL for citations), as evidenced by Yen et al. (US-20220311097-A1), and as further evidenced by ChemEurope.com Encyclopedia (hereinafter ChemEurope; “Hildebrand solubility parameter”; see attached NPL for citations), as applied to Claim 1, above, and in further view of Nishikawa et al. (JP-2003007279-A; previously cited; see also NPL provided 08/25/2025 for citations).
Regarding Claim 5, modified Seo renders obvious all of the limitations as set forth above. Seo discloses that the surface area of the inorganic particles increases significantly due to plural pores existing in the particle itself [0038]. As an example, Seo discloses that the surface area of the inorganic particles may fall within a range of 10 to 50 m2/g [0038]. Seo does not teach that the specific surface area of the secondary particles is greater than or equal to 100 m2/g.
Nishikawa teaches a similar separator for a secondary battery [0005, 0008, 0010] which includes a porous inorganic filler [0010-0012], an organic polymer [0012], and a porous membrane [0012]. Nishikawa teaches that the specific area of the porous inorganic filler is preferably 300 m2/g or more [0021]. Advantageously, such porous inorganic filler is able to be successfully impregnated with electrolyte and therefore has ionic conductivity [0021]. Accordingly, the ionic conductivity of the separator is not reduced, which is preferable from the viewpoint of battery characteristics [0021].
Therefore, one of ordinary skill in the art, before the effective filing date of the claimed invention, would have found it obvious to have chosen in the specific surface area of the secondary particles (inorganic particles) to be greater than or equal to 300 m2/g, which is within the claimed range of greater than or equal to 100 m2/g, with a reasonable expectation that such a specific surface area would result in a successful secondary particles (inorganic particles) capable of maintaining the ionic conductivity of the separator of Seo.
Claim(s) 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Seo et al. (US-20070122716-A1; previously cited) in view of Tanaka et al. (US-20180053963-A1; previously cited) and in view of Kajita et al. (US-20130059192-A1) and as evidenced by Kawakami et al. (US-20140377630-A1), as evidenced by Lee et al. (US-20110027642-A1), as evidenced by Hony Engineering Plastics Limited (hereinafter HONY; “Dielectric Constants of Commonly Used Polymer Plastics”; see attached NPL for citations), as evidenced by Yen et al. (US-20220311097-A1), and as further evidenced by ChemEurope.com Encyclopedia (hereinafter ChemEurope; “Hildebrand solubility parameter”; see attached NPL for citations), as applied to Claim 1, above, and in further view of Hamada et al. (US-20210057703-A1).
Regarding Claim 17, modified Seo renders obvious all of the limitations as set forth above. Seo discloses that the separator is designed to secure mechanical strength [0037, 0045, 0050, 0057-0058, 0074]. Seo does not teach the transverse-direction tensile strength of the separator, and therefore does not teach that the transverse-direction tensile strength is greater than or equal to 2000 kgf/cm2.
Hamada teaches that the tensile strength of a coated separator is preferably 500 kgf/cm2 to 3000 kgf/cm2 [0004, 0023, 0028, 0056, 0066-0068, 0205-0206]. A separator with such a tensile strength is able to be successfully used in battery [0015-0018, 0028, 0269], and provides a balance between adhesion and strength [0011, 0206-0208].
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have selected the transverse-direction tensile strength of the separator to be 500 kgf/cm2 to 3000 kgf/cm2 with a reasonable expectation that such a tensile strength would result in a successful separator.
Although modified Seo does not explicitly teach that the transverse-direction tensile strength is greater than or equal to 2000 kgf/cm2, the range rendered obvious by the prior art overlaps the claimed range. It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have selected the overlapping portion of the range with a reasonable expectation that a transverse-direction tensile strength of 2000 kgf/cm2 to 3000 kgf/cm2 would result in a successful battery separator.
Claim(s) 1, 11-13 and 15-17 is/are further rejected under 35 U.S.C. 103 as being unpatentable over Seo et al. (US-20070122716-A1; previously cited) in view of Ryu et al. (US-20190326579-A1; previously cited) and in further view Lee (EP-3407413-B1; previously cited).
Regarding Claims 1, 11 and 17, Seo discloses a separator comprising a substrate (porous substrate) and a coating (organic/inorganic composite layer) provided on at least one side of the substrate ([0003, 0023-0024, 0074]; see Fig. 2). The coating (organic/inorganic composite layer) comprises a binder polymer and inorganic particles with a pore structure [0023-0024].
The inorganic particles disclosed by Seo read on second particles comprising secondary particles having a pore structure (see Fig. 2; [0024, 0083, 0091, 0093]).
Seo discloses that binder polymer is designed to absorb electrolyte to provide ion conductivity, thus resulting in a gel type organic/inorganic composite electrolyte [0052]. Such an electrolyte improves battery performance [0052]. Seo discloses that the binder polymer can include, from a list of possible candidates, polymethylmethacrylate, polyacrylonitrile, mixtures thereof, or other materials which may be used alone or in combination [0053]. Seo also discloses that the coating (organic/inorganic composite layer) may include other additives [0054]. Seo does not teach first particles comprising primary particles comprising silicone particles as required by Claims 1 and 11, and therefore does not teach the claimed first, second, and third structural units required by Claim 11.
Ryu teaches a composite separator comprising a porous substrate coated with a composite electrolyte layer including a block copolymer, an ionic liquid, and a particle [0008]. The particle can be an organic particle, an organic-inorganic particle or a combination thereof [0008, 0108]. As a possible embodiment of a particle, Ryu teaches a cage-structured silsesquioxane [0108, Claim 18]. Ryu teaches that the organic particle may have a polymer segment (e.g. a block) which is the same as a polymer or polymer segment of the block copolymer [0107]. The block copolymer can comprise a polymer such as polymethylmethacrylate and poly(acrylonitrile) [0101-0102, 0104].
Advantageously, Ryu teaches that the block copolymer and the particle serve to increase the ion conductivity of the separator and improve mechanical strength as well as thermal stability [0056]. Furthermore, the composite separator has improved wettability to the electrolyte solution [0168].
Therefore, one of ordinary skill in the art, before the effective filing date of the claimed invention, would have found it obvious to have included organic particles (reads on primary particles) and an ionic liquid as taught by Ryu in the coating (organic/inorganic composite layer) of modified Seo with a reasonable expectation that such a modification would result in a successful coating capable of increasing the ion conductivity and improving the mechanical strength, thermal stability, and wettability of the separator of Seo.
Furthermore, one of ordinary skill in the art, before the effective filing date of the claimed invention, would have found it obvious to have selected the primary particles (organic particles) to be a polymer comprising polymethylmethacrylate, poly(acrylonitrile) and cage-structured silsesquioxane with a reasonable expectation that such a particle would result in a successful coating layer.
The organic particles comprising cage-structured silsesquioxane reads on the recited limitation of first particles comprising primary particles comprising silicone particles as required by Claims 1 and 11 (see 112(b) rejection of Claim 11, above).
Polymethylmethacrylate reads on the recited limitation of a first structural unit represented by formula (I) (i.e. R1 and R2 are both methyl groups, which is within the claimed list of possible R1 and R2 candidates) as required by Claim 11.
Poly(acrylonitrile) reads on the recited limitation of a second structural unit represented by formula (II) (i.e. R3 is hydrogen, which is within the claimed list of possible R3 candidates) as required by Claim 11.
Seo discloses that the secondary particles (inorganic porous particles) reduce the weight of the battery, leading to an increase in energy density per unit weight of the battery [0034, 0047]. If the content of secondary particles (inorganic particles) is too low, the content of binder polymer becomes such that the interstitial volume formed among the secondary particles (inorganic particles) is decreased and battery quality is degraded [0047]. Meanwhile, if the content of the secondary particles (inorganic particles) is too high, sufficient adhesion is not achieved and the mechanical properties of the coating is degraded [0037]. The mixing ratio of secondary particles (inorganic particles) to binder polymer is from 50%:50% to 97%:3% by weight [Claim 10]. Such a content of secondary particles ensures mechanical properties while preventing an excessive amount of binder polymer from decreasing the porosity and degrading of the quality of the battery [0047]. Modified Seo also teaches that the primary particles (organic particles) improve mechanical strength as well as thermal stability [Ryu: 0056] and result in a composite separator with improved wettability to the electrolyte solution [Ryu: 0168].
Therefore, although Seo does not teach that a ratio of a weight proportion A of the primary particles and a weight proportion B of the secondary particles satisfies 1<A/B≤20 as required by Claim 1, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have optimized the content of primary particles (organic particles), secondary particles (inorganic particles), and binder polymer, including selecting the ratio of primary particles to secondary particles to satisfy 1<A/B≤20, with a reasonable expectation that such a ratio of primary particles to secondary particles would achieve a successful balance between mechanical strength, thermal stability, and wettability, and battery quality and porosity, and adhesion (MPEP 2144.05, II).
Although modified Seo teaches a cage-structured silsesquioxane, modified Seo does not teach the exact structure of the cage-structured silsesquioxane, and therefore does not teach that the third structure is represented by formula (III) as required by Claim 11.
Lee teaches a cage-structured silsesquioxane [0047] which can be used in an electrolyte composition for a lithium secondary battery [0024, 0109-0110]. The cage-structured silsesquioxane is includes a polymerizable reactive group [0027, 0041-0043, 0047-0048] such that the cage-structured silsesquioxane can be successfully coupled to a block copolymer [0024]. The block copolymer [0024] can include polymethylmethacrylate [0067, 0091] and polyacrylonitrile [0081-0082, 0090]. The cage-structured silsesquioxane is represented by Formula 2 (see below). At least one functional group (R1-R8) of the cage-structured silsesquioxane can be a methacryloxypropyl group [0050-051]. The other functional groups can be, for example, a substituted or unsubstituted C1-C30 alkyl group [0048].
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Both modified Seo and Lee teach a cage-structured silsesquioxane which can be coupled to polymethylmethacrylate and polyacrylonitrile. Therefore, although not disclosed in a specific embodiment, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have selected the cage-structured silsesquioxane of modified Seo to be that depicted in Formula 2, wherein R1-R7 are each a substituted or unsubstituted C1-C10 alkyl group, and wherein R8 is a methacryloxypropyl group, with a reasonable expectation that such a selection would result in a successful cage-structured silsesquioxane capable of being successfully coupled to polymethylmethacrylate and polyacrylonitrile.
Accordingly, modified Seo renders obvious a third structural unit represented by formula (III) as required by Claim 11. The use of a methacryloxypropyl group as a substituent corresponds to a structural unit represented by formula (III-1) as evidenced by the instant specification [instant specification: 00135, 00233].
Regarding Claim 17, modified Seo renders obvious a separator which is substantially similar to the separator disclosed in the instant specification. Therefore, it is understood that the separator would inherently exhibit: a machine-direction thermal shrinkage rate; a transverse-direction thermal shrinkage rate; an air permeability; a machine-direction tensile strength; a transverse-direction tensile strength; a wetted length; and an ionic conductivity as claimed. Specifically, the prior art renders obvious a porous substrate, porous inorganic particles, and silicone particles which are substantially similar those recited in the instant application [instant specification: 0087, 00223, 00238]. Therefore, the separator of the prior art is understood to inherently exhibit the claimed properties (MPEP 2112.01, I-II).
Regarding Claims 12-13, modified Seo renders obvious all of the limitations as set forth above. Modified Seo further teaches that the first structural unit (polymethylmethacrylate) is an ion-conductive segment [Ryu: 0101-0102], the second structural unit (polyacrylonitrile) is a structural segment [Ryu: 0101, 0104], and the third structural unit (cage-structured silsesquioxane) may aid in improving the mechanical strength of the separator [Ryu: 0056].
Although modified Seo does not explicitly teach the relative ratio of each component, one of ordinary skill in the art, before the effective filing date of the claimed invention, would have been found it obvious to have optimized the relative contents of the first structural unit, the second structural unit, and the third structural unit in order to strike a balance between ion conductivity, structural strength, and mechanical strength (MPEP 2144.05, II), including selecting the molar amount of the first structural unit (a) to be 70≤a≤90 as required by Claim 12 and selecting the ratio of a/b to be 4≤a/b≤15, as required by Claim 13 with a reasonable expectation that such a content of first structural unit and such a ratio of first structural unit to second structural unit would result in a successful primary particle with increased ionic conductivity, as desired by Seo [Seo: 0052].
Regarding Claim 15, modified Seo renders obvious all of the limitations as set forth above. Seo discloses that the separator is designed to have a reduced weight in order to increase energy density per unit weight of a device [0010, 0023]. Modified Seo further teaches that the first structural unit (polymethylmethacrylate) is an ion-conductive segment [Ryu: 0101-0102], the second structural unit (polyacrylonitrile) is a structural segment [Ryu: 0101, 0104], and the third structural unit (cage-structured silsesquioxane) may aid in improving the mechanical strength of the separator [Ryu: 0056]. Modified Seo does not teach the average molecular weight of the silicone particles.
Lee teaches that the molecular weight of the ion-conductive domain (corresponds to first structural unit) and the structural domain (corresponds to second structural unit) can be selected in view of improving ionic conductivity and mechanical properties [0085-0087].
Although modified Seo does not explicitly teach that the number weight average molecular weight of the silicone particles is 35,000 to 70,000, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have optimized the number weight average molecular weight of the silicone particles in order to achieve a balance between keeping the battery separator as light as possible while ensuring sufficient ionic conductivity and mechanical properties (MPEP 2144.05, II). One of ordinary skill in the art would have a reasonable expectation that a number weight average molecular weight of 35,000 to 70,000 would result in a successful separator for use in a battery.
Regarding Claim 16, modified Seo renders obvious all of the limitations as set forth above. Seo discloses a specific embodiment (Example 1) wherein the porosity of the substrate (polyethylene film) is 45% [0083], which is within the claimed range of “greater than or equal to 25%”.
Response to Arguments
Applicant's arguments filed 11/25/2025 have been carefully considered but they are not persuasive.
Applicant has argued that Seo fails to teach the identity of the primary particles as currently claimed (Remarks, Pg. 10). In response, Examiner notes that Claim 1 now relies on Kajita to render obvious the use of polysulfone particles. Furthermore, previously presented Claim 11 required silicone particles (see Non-Final Rejection mailed 08/25/2025 at Pgs. 20-23). Since no error has been pointed out in the previous rejection of Claim 11, the rejection has been maintained (with necessary changes to reflect the amendment made to Claim 1; see rejection of Claims 1 and 11, above).
Applicant has argued that Seo does not disclose, teach, or suggest that the binder polymer is in the form of particles (Remarks, Pg. 10). In response, Examiner notes that, under a first rejection of Claim 1, Tanaka is relied upon to render obvious the binder polymer of Seo in the form of particles. Under a further rejection of Claim 1 (see rejection of Claims 1 and 11), organic particles including silicone particles are rendered obvious.
Applicant has argued that Seo does not disclose, teach, or suggest that the primary particles satisfy the claimed weight proportion (Remarks, Pg. 10). Examiner notes that this limitation was previously found in Claim 6. Since no specific error has been pointed out in this rejection, the rejection is maintained and applied to Claim 1.
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.
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/D.C.N./Examiner, Art Unit 1751
/JONATHAN G LEONG/Supervisory Patent Examiner, Art Unit 1751 1/9/2026
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