DETAILED ACTION
Status of Claims
Claims 1 and 3 are pending and presented for examination on the merits.
Claim 1 is currently amended.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 02/18/2026 was filed after the mailing date of the non-final Office action on 08/21/2025. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the IDS is being considered by the examiner.
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 1 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over JP H09-249916 (A) to Watanabe et al. (“JP ʹ916”) (abstract and computer-generated translation are attached).
Regarding claim 1, JP ʹ916 discloses a method for producing a grain-oriented silicon steel sheet (method for producing a grain-oriented electrical steel sheet). Abstract. The method includes steps of (i) providing a slab; (ii) hot rolling; (iii) cold rolling once or multiple times including intermediate annealing to a final sheet thickness; (iv) decarburization annealing; (v) applying an annealing separator to the steel sheet surface before final annealing; and (vi) final annealing. Para. [0009], [0015].
The slab contains C 0.02-0.1 wt.% and Si 2.0-4.0 wt.% (abstract; para. [0009], [0027]; claim 1), which fall within the claimed ranges. Mn may be added in amounts of 0.03-0.10 wt.% (para. [0015], [0028], [0036]), which falls within the claimed range. An auxiliary inhibitor like V can be added in an amount of 0.01-0.2 wt.% in total, alone or in combination with other auxiliary inhibitors (para. [0029]), which overlaps the claimed range. The slab is steel (iron and inevitable impurities as the balance). Para. [0009].
The annealing separator uses MgO as the main component. Para. [0031]. The annealing separator may contain an additive (metal compound) of one or more of oxides, hydroxides, and sulfates of one or more of Sn, Bi, and Sb, among other elements, in an amount of 0.6-7 parts by weight per 100 parts by weight of MgO (para. [0010]-[0012], [0032], [0033]), which overlaps the claimed range.
The average particle size of the aforementioned additive (metal compound) ranges from 0.3 µm to 15 µm. Para. [0010], [0012], [0023], [0024], [0033]; claim 2. The particles may be selected to closer to or approaching the lower limit of 0.3 µm, as implied by the range, suggesting that the additives need not be larger than 1 µm (ratio of particles with a particle size of 1 µm or more in the metal compound being 0.0010 particles per µm2 or less).
The overlap between the ranges taught in the prior art and recited in the claims creates a prima facie case of obviousness. MPEP § 2144.05(I). It would have been obvious for one of ordinary skill in the art to select from among the prior art ranges because there is utility over an entire range disclosed in the prior art.
Regarding claim 3, JP ʹ916 discloses that the steel slab may further constitute an inhibitor. Para. [0028]. When AlN is used as an inhibitor, the Al content is 0.01-0.04 wt.% and the N content is 50-120 ppm (0.0050-0.0120 wt.%), each of which overlaps the claimed ranges. Para. [0028].
In addition to a main inhibitor, auxiliary inhibitors include Cu, Sn, Cr, Sb, Mo, and P, among others, alone or in combination in amount of 0.01-0.2 wt.% in total (para. [0029]), which overlaps the claimed ranges.
Claims 1 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over JP ʹ916 in view of US 2014/0251514 (A1) to Watanabe et al. (“US ʹ514”).
Regarding claim 1, JP ʹ916 discloses a method for producing a grain-oriented silicon steel sheet (method for producing a grain-oriented electrical steel sheet). Abstract. The method includes steps of (i) providing a slab; (ii) hot rolling; (iii) cold rolling once or multiple times including intermediate annealing to a final sheet thickness; (iv) decarburization annealing; (v) applying an annealing separator to the steel sheet surface before final annealing; and (vi) final annealing. Para. [0009], [0015].
The slab contains C 0.02-0.1 wt.% and Si 2.0-4.0 wt.% (abstract; para. [0009], [0027]; claim 1), which fall within the claimed ranges. Mn may be added in amounts of 0.03-0.10 wt.% (para. [0015], [0028], [0036]), which falls within the claimed range.
The annealing separator uses MgO as the main component. Para. [0031]. The annealing separator may contain an additive (metal compound) of one or more of oxides, hydroxides, and sulfates of one or more of Sn, Bi, and Sb, among other elements, in an amount of 0.6-7 parts by weight per 100 parts by weight of MgO (para. [0010]-[0012], [0032], [0033]), which overlaps the claimed range.
The average particle size of the aforementioned additive (metal compound) ranges from 0.3 µm to 15 µm. Para. [0010], [0012], [0023], [0024], [0033]; claim 2. The particles may be selected to closer to or approaching the lower limit of 0.3 µm, as implied by the range, suggesting that the additives need not be larger than 1 µm (ratio of particles with a particle size of 1 µm or more in the metal compound being 0.0010 particles per µm2 or less).
The overlap between the ranges taught in the prior art and recited in the claims creates a prima facie case of obviousness. MPEP § 2144.05(I). It would have been obvious for one of ordinary skill in the art to select from among the prior art ranges because there is utility over an entire range disclosed in the prior art.
With respect to the addition of at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, and Ta, JP ʹ916 teaches that auxiliary inhibitors Cu, Sn, Cr, Sb, Ge, Mo, Te, Bi, P, and V can be added, alone or in combination with one another, in an amount of 0.01-0.2 wt.% in total. Para. [0029].
Where V is added as an auxiliary inhibitor, it can be added in combination with another element to reach the total of 0.01-0.2 wt.%, but JP ʹ916 is silent as to a specific proportion of V if it is added in combination with another element.
US ʹ514 is directed to a grain-oriented electrical steel sheet. Abstract; para. [0002]. The steel sheet may further contain V 0.005-0.1% by mass (para. [0017], [0054]), which overlaps the claimed range. These elements have the effect of reinforcing an inhibitor effect that stably enhances magnetic flux density. Para. [0055].
JP ʹ916 seeks to avoid great variations in magnetic flux density. Para. [0017]. Therefore, it would have been obvious to one of ordinary skill in the art to have added V in the steel slab of JP ʹ916 in the amounts taught by US ʹ514 when multiple auxiliary inhibitors are present because they would provide stability and enhance magnetic flux density of the electrical steel sheet.
Where V is not selected as auxiliary inhibitor in JP ʹ916, it would be omitted (zero percent). JP ʹ916 does not teach adding Ti, Zr, Hf, Nb, and Ta.
US ʹ514 is directed to a grain-oriented electrical steel sheet. Abstract; para. [0002]. The steel sheet may further contain one or more of Ti 0.005-0.1% by mass and Nb 0.005-0.1% by mass (para. [0017], [0054]), each of which overlap the claimed range. These elements have the effect of reinforcing an inhibitor effect that stably enhances magnetic flux density. Para. [0055].
It would have been obvious to one of ordinary skill in the art to have added Ti and/or Nb in the amounts taught by US ʹ514 to the steel slab of JP ʹ916 because these elements would stabilize and improve magnetic flux density of the electrical steel sheet.
Regarding claim 3, JP ʹ916 discloses that the steel slab may further constitute an inhibitor. Para. [0028]. When AlN is used as an inhibitor, the Al content is 0.01-0.04 wt.% and the N content is 50-120 ppm (0.0050-0.0120 wt.%), each of which overlaps the claimed ranges. Para. [0028].
In addition to a main inhibitor, auxiliary inhibitors include Cu, Sn, Cr, Sb, Mo, and P, among others, alone or in combination in amount of 0.01-0.2 wt.% in total (para. [0029]), which overlaps the claimed ranges.
Response to Arguments
Applicant’s arguments filed on 11/11/2025 with regard to Park (WO 2008/047999 (A1)) in view of Watanabe (US 2014/0251514 (A1)) have been considered, but they are moot because the new ground of rejection does not rely on this combination of references to reject the claims. Park is no longer used to reject the claims in this Office action. Watanabe (US ʹ514) is cited in this Office action, but is utilized in combination with new reference JP ʹ916, thereby rendering the argument moot.
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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/VANESSA T. LUK/Primary Examiner, Art Unit 1733
February 26, 2026