DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendment
In response to the amendment received 03/26/2026, the 35 U.S.C. 103 rejections of claims 3-16 and 35 U.S.C. 112(b) rejection of claim 15 have been withdrawn from the previous office action.
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) 3-7, 9-14, and 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Published Application US20150380702A1 (supplied by applicant), hereafter Lee, in view of Published Application US20130287937A1, hereafter Joo.
Regarding claim 3, Lee discloses a method for manufacturing a porous separator ([0024], method for manufacturing a separator; [0026] porous) for a lithium secondary battery ([0002] lithium secondary battery), the porous separator comprising:
a porous polymer substrate ([0012] porous substrate is polyolefin-based porous film) having a first surface and a second surface opposite to the first surface;
a first porous coating layer ([0010] porous organic-inorganic composite layer on the porous substrate) on the first surface of the porous polymer substrate, wherein the first porous coating layer comprises inorganic particles and a binder polymer ([0010] slurry containing inorganic particles and formed by dissolving a binder polymer); and
a second porous coating layer ([0010] porous organic-inorganic composite layer on the porous substrate) on the second surface of the porous polymer substrate ([0010] (S2) coating at least one surface, thus it may be both surfaces), wherein the second porous coating layer comprises the inorganic particles and the binder polymer ([0010] slurry containing inorganic particles and formed by dissolving a binder polymer),
wherein the method comprises the steps of:
(S1) applying a solvent for pore impregnation onto the first surface of the porous polymer substrate ([0027] at least one surface of porous substrate is coated with a first solvent – the examiner notes this implies the coating of one or both sides with the first solvent);
(S2) applying a slurry for forming the second porous coating layer, comprising inorganic particles, an organic solvent and a binder polymer soluble in the organic solvent ([0031] slurry containing inorganic particles dispersed therein and formed by dissolving a binder polymer in the second solvent), onto the second surface of the porous polymer substrate ([0031] the formed first solvent is coated with the slurry);
(S3) applying the slurry for forming the first porous coating layer onto the first surface of the porous substrate ([0031] the formed first solvent is coated with the slurry); and
(S4) drying the product of step (S3) to obtain the porous separator having the first porous coating layer on the first surface of the porous polymer substrate and the second porous coating layer on the second surface of the porous polymer substrate ([0047] first solvent applied onto porous substrate and second solvent in slurry are dried simultaneously so that a porous organic-inorganic composite layer is formed on the porous substrate).
Lee is silent on wherein the first porous coating layer and the second porous coating layer have a deviation in peel strength of ±100 gf/15 mm, and wherein the first porous coating layer and the second porous coating layer have a deviation in lamination strength of ±50 gf/25 mm
However, Lee also discloses that the pore size and porosity of the coating layer may be reduced if the content of inorganic particles is too low, and further states that as the amount of inorganic particles present in the coating layer exceeds 99 parts by weight, the peeling resistance of the coating layer may deteriorate since the content of the binder polymer is small ([0040]).
Since the peel strength and lamination strength decrease with increasing amounts of inorganic particles, and since the peel strength and lamination strength are measures of the adhesion between the layers of the separator, one skilled in the art would have found it obvious, before the effective filing date of the present invention, to modify the invention of Lee to modify the peel and lamination strengths across the layers of the separator by tuning the amount of inorganic particles in order to effectively bind the layers together securely while ensuring the pore size and porosity of the coating layer are at a desirable level and arrive at the claimed deviations absent any evidence of unexpected results.
Lee is further silent on applying the solvent for pore impregnation only to the first surface of the porous polymer substrate.
In the analogous art of battery separator manufacturing, Joo discloses applying the solvent for pore impregnation only to the first surface of the porous polymer substrate ([0013] applying a solvent to at least one face of the microporous film substrate to fill and protect pores of the microporous film). Joo further discloses that filled pores may show considerably reduced penetration of the coating solution into the pores, thus retaining the final product’s initial permeability ([0030]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the present invention, to further modify the invention of Lee to coat only one side of the substrate with solvent in order to avoid wasted solvent and remove unnecessary process steps, since Joo discloses the pores of the film will be filled and protected from clogging by the solvent, and one skilled in the art would thus have understood that since the pores of the substrate have been filled already from one side, filling them again from the other side of the substrate is not needed.
Regarding claim 4, Lee discloses wherein step (S2) and step (S3) are carried out sequentially (this is implicit, since Lee discloses sequentially coating the solvent followed by the slurry in [0045], and Lee does not disclose a coating method for coating both sides with slurry simultaneously, and Fig 1 shows the use of a slot die coater on one side) with a time interval (implicit in sequential operation that if one step happens after another, time passes between each step). That being said, it is also further the case that the selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results (MPEP 2144.04 (IV) (C)).
Regarding claim 5, Lee discloses wherein the applying step is carried out through a single-side coating process (Fig 1, [0045] slot die coating).
Regarding claim 6, Lee discloses wherein the single-side coating process is carried out by using a slot die coater (Fig 1, [0045] slot die coating).
Regarding claim 7, Lee discloses wherein the solvent for pore impregnation is the same as the organic solvent, or is miscible with the binder polymer and has a low boiling point ([0055-0056] acetone for both solvents).
Regarding claim 9, Lee discloses wherein the solvent for pore impregnation has a boiling point of 100C or higher and 300°C or lower ([0056] solvent is acetone – which has a boiling point of 56°C).
Regarding claim 10, Lee discloses wherein the solvent for pore impregnation comprises acetone ([0055-0056] acetone for both solvents).
Regarding claim 11, Lee discloses wherein the organic solvent comprises acetone ([0055-0056] acetone for both solvents).
Regarding claim 12, Lee discloses wherein step (S1) comprises applying the solvent for pore impregnation inside of the pores of the porous polymer substrate (this is implicit, since in [0055-0056] the 45% porous substrate is being first coated with acetone – this will lead to acetone infiltrating the pores).
Regarding claim 13, Lee discloses wherein step (S4) comprises drying the solvent for pore impregnation and the organic solvent ([0047] first solvent applied onto porous substrate and second solvent in slurry are dried simultaneously).
Regarding claim 14, Lee discloses wherein a solid content of solute free from the solvent in the slurry for forming the first porous coating layer and the second porous coating layer is 30 wt% or less based on 100 wt% of the slurry ([0055] weight ratio of 10:90 binder polymer to inorganic particles in slurry).
Regarding claim 16, Lee discloses wherein the slurry for forming the second porous coating layer in step (S2) has the same composition as the composition of the slurry for forming the first porous coating layer in step (S3) ([0027] solvent applied to at least one surface, slurry applied to solvent coating - thus, same slurry applied to both surfaces to which solvent was applied).
Claim(s) 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Published Application US20150380702A1 (supplied by applicant), hereafter Lee, in view of Published Application US20130287937A1, hereafter Joo, as stated above for claim 3, as further evidenced by Kutz, Myer. (2017). Applied Plastics Engineering Handbook - Processing, Materials, and Applications (2nd Edition) - 7.3 Biodegradable Polymers Derived from Renewable Resources. Retrieved from https://app.knovel.com/hotlink/pdf/id:kt011DY9E5/applied-plastics-engineering/biodegradable-polymers, hereafter Kutz.
Regarding claim 8, Lee discloses wherein the solvent for pore impregnation has a boiling point lower than a melting point of the porous polymer substrate ([0057] dried at 50°C; [0056] solvent is acetone – which has a boiling point of 56°C, and substrate is polyethylene membrane, which has a melting point of 110-129°C, as evidenced by Kutz (Page 136, Table 7.3).
Claim(s) 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Published Application US20150380702A1 (supplied by applicant), hereafter Lee, in view of Published Application US20130287937A1, hereafter Joo, as stated above for claim 3, and further in view of Published Application US20090246613A1 (supplied by applicant), hereafter Park.
Regarding claim 15, Lee discloses wherein step (S4) is carried out ([0047] first solvent applied onto porous substrate and second solvent in slurry are dried).
Lee is silent on wherein the drying is performed under a relative humidity of 20% to 80%.
In the analogous art of separator manufacturing, discloses wherein the drying is performed under a relative humidity of 10% to 80% ([0038]), which overlaps with the claimed range of 20% to 80%.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the present invention, to select a relative humidity between 20% and 80% for the drying process, as disclosed by Park since ambient humidity conditions are typically between 20% and 80% and no special vacuum or climate control equipment would be necessary to provide a controlled environment for drying the separator, reducing costs.
Response to Arguments
Applicant's arguments filed 03/26/2026 have been fully considered but they are not persuasive.
In response to applicant’s arguments on page 9 of applicant’s remarks that it is unreasonable to assert that the single slurry application step in Lee corresponds to the claimed steps (S2) and (S3), the examiner notes that according to the broadest reasonable interpretation of the claim, the claim does not require these steps to be performed separately and/or sequentially, the claim only requires that they each are performed.
In response to applicant’s arguments on page 9 of applicant’s remarks that the prima facie obviousness rationale is rebutted by the comparative evidence in the specification, with the Comparative Example 1 not including application of the solvent to the first surface of the substrate, the examiner notes this does not demonstrate unexpected results, as the rejection pointed out that one skilled in the art would have found it obvious to maximize the peel and lamination strengths by other means, and the claimed method does not limit the method only to the steps claimed, due to the use of the open-ended claim language of “comprising”.
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 TIMOTHY HEMINGWAY whose telephone number is (571)272-0235. The examiner can normally be reached M-Th 6-4.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Susan Leong can be reached at (571) 270-1487. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/T.G.H./Examiner, Art Unit 1754
/SUSAN D LEONG/Supervisory Patent Examiner, Art Unit 1754
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