DETAILED ACTION
Response to Amendment
The Amendment filed 07/16/2026 has been entered. Claims 1-9 and 11-14 remain pending in the application. Claims 1-6 and 11-14 have been withdrawn due to a restriction requirement. Claims 10 and 15-18 have been canceled. No new claims have been added. The 112(d) rejections previously set forth in the Non-Final Rejection mailed 04/16/2026 are withdrawn in view of Applicant’s cancellation of claims 15-17.
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.
Claims 7-9 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2018/117673 A1 of Kwon (hereafter WO’673, as cited in IDS mailed 10/11/2023, using US 2019/0323104 A1 as its English translation).
Regarding claims 7-9, WO’673 teaches an annealing separator composition for a grain-oriented electrical steel sheet (Abstract). WO’673 teaches a grain oriented electrical steel sheet wherein a coating comprising mullite and forsterite is formed on one or both sides of a substrate of a grain-oriented electrical steel sheet (claim 1, reads on claimed grain-oriented electrical steel sheet comprising a coating layer disposed on one or both surfaces of a grain-oriented electrical steel sheet substrate; coating reads on claimed coating layer).
Instant claims (wt%)
WO’673 (wt%)
Mg
1-20
3-80
Metal M (one or more of Be, Ba, Sr, Sn, Mn, Co, Ni, Cu, and Zn)
17.5-35
-
Si
15-50
3-80
Fe
≤ 20
Remainder
O
Balance (“and unavoidable impurities”)
3-80
Al: 0.5-50
Coating layer thickness
0.1-10 μm
0.1-10 μm (claim 10)
Ceramic layer thickness
0.5-5 μm
0.5-5 μm ([0065])
WO’673 teaches a coating with a composition (claims 7-9) overlapping with the claimed coating, as shown in List 1, with the exception of metal M. 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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997). See MPEP § 2144.05 I.
WO’673 therefore reads on the limitation a grain-oriented electrical steel sheet comprising a coating layer disposed on one or both surfaces of a grain-oriented electrical steel sheet substrate, wherein the coating layer contains 1 to 20 wt% of Mg, 15 to 50 wt% of Si, 20wt% or less of Fe, and a balance of O and unavoidable impurities of claim 7.
Regarding metal M of claim 7, WO’673 teaches the annealing separator is applied to a substrate of a grain-oriented electrical steel sheet to form a coating comprising mullite and forsterite ([0045], one of ordinary skill in the art understands the composition of the annealing separator directly impacts the composition of the resulting coating). WO’673 teaches the annealing separator further comprises 0.1 to 20 wt% metal hydroxide which may comprise at least one selected from Ni(OH)2, Co(OH)2, Cu(OH)2, Sr(OH)2, Ba(OH)2, Pd(OH)2, In(OH)3, Bi(OH)3 and Sn(OH)2 to form a uniform coating, and obtain excellent magnetic quality ([0051]-[0053], Ni, Co, Cu, Sr, Ba and Sn of the metal hydroxides read on claimed metal M). WO’673 teaches the annealing separator may further comprise 0.5 to 10 wt% of MnO to improve the insulating property of the formed coating ([0055], Mn of MnO reads on claimed metal M). WO’673 teaches the annealing separator may further comprise 0.5 to 10 wt% of SrSO4, BaSO4, or a combination thereof to improve surface gloss and roughness ([0056], Sr and Ba of SrSO4 and BaSO4 read on claimed metal M). WO’673 further teaches an inventive example (Example 2, Table 1) of an annealing separator with 20 wt% Cu. While WO’673 does not teach the Ni, Co, Cu, Sr, Ba, Sn, or Mn content of the resulting coating when adding metal hydroxide, MnO, SrSO4 and/or BaSO4, one of ordinary skill in the art would reasonably expect Ni, Co, Cu, Sr, Ba, Sn, or Mn to be present in the coating when adding metal hydroxide, MnO, SrSO4 and/or BaSO4 to the annealing separator, as taught by WO’673.
In other words, since the annealing separator includes Ni, Co, Cu, Sr, Ba, Sn, and/or Mn, one of ordinary skill in the art would reasonably expect the resulting coating to include Ni, Co, Cu, Sr, Ba, Sn, and/or Mn. Regarding the amount of metal M in the coating, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the amounts of metal hydroxide, MnO, SrSO4 and/or BaSO4 in the annealing separator and consequently in the resulting coating, such as within claimed ranges, to obtain a uniform coating, improve insulating property of the formed coating, improve surface gloss, and obtain excellent magnetic quality, as taught by WO’673.
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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997). See MPEP § 2144.05 I.
WO’673 therefore reads on the limitation 17.5 to 35 wt% of a metal M of claim 7 and wherein the metal M is one or more of Be, Ba, Sr, Sn, Mn, Co, Ni, Cu, and Zn of claim 7.
Regarding the ceramic layer of claims 8 and 9, WO’673 teaches a ceramic layer formed on the coating (claim 11, reads on claimed further comprising a ceramic layer disposed on the coating layer). WO’673 teaches a thickness of the coating is 0.1 to 10 μm (claim 10) and a thickness of the ceramic layer may be 0.5 to 50 μm ([0065]). The coating thickness and ceramic layer thickness ranges of WO’673 are identical to those of the claimed invention.
WO’673 therefore reads on the limitation further comprising a ceramic layer disposed on the coating layer of claim 8, and wherein: a thickness of the coating layer is 0.1 to 10 μm and a thickness of the ceramic layer is 0.5 to 5 μm of claim 9.
Response to Arguments
Applicant’s arguments, see pages 7-9 with respect to claims 7-9, filed 07/16/2026 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. The new ground of rejection was selected to address the amended claim 7 removing Ca as one of the possible metal M elements.
Regarding arguments with respect to claims 15-17 (remarks, page 9), the Examiner notes these arguments are moot since claims 15-17 are now cancelled.
Citation of Pertinent Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
WO 2017/105111 A1 of Kwon (hereafter WO’111, using US 2018/0374600 A1 as its English translation) is considered relevant to claims 7 and 9. WO’111 teaches an insulation coating composition for grain-oriented electrical steel sheet (Title). WO’111 teaches an insulation coating composition for a grain-oriented electrical steel sheet, comprising: 0.1 to 10 wt % of an inorganic nitride; 30 to 60 wt % of colloidal silica; and 30 to 60 wt % of a metal phosphate wherein the inorganic nitride comprises a nitride of at least one of Mg, Si and Ba (claim 1), and wherein the metal phosphate is one of at least Mg and Sn (claim 4). WO’111 teaches a thickness of the insulation coating is 0.2 to 4 μm (claim 21), which overlaps with the claimed invention. While WO’111 does not teach the coating composition in terms of individual elements, the coating compositions include elements overlapping with the claimed invention.
Conclusion
Applicant amended claim 7 to exclude Ca from the list of possible metal M. 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 extension fee 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 date of this final action.
Contact Information
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MAYELA ALDAZ whose telephone number is (571)270-0309. The examiner can normally be reached Monday -Thursday: 10 am - 7 pm and alternate Friday: 10 am - 6 pm.
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/M.A./Examiner, Art Unit 1733
/REBECCA JANSSEN/Primary Examiner, Art Unit 1733
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