DETAILED ACTION
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 06/30/2026 has been entered.
Status of Claims
Claims 1-7, 9-17, 19, and 20 are pending. Of the pending claims, claims 1-7, 12-17, 19, and 20 are presented for examination on the merits, and claims 9-11 are withdrawn from examination.
Claim 1 is currently amended.
Information Disclosure Statement
One (1) information disclosure statement (IDS) was submitted on 07/30/2026. 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 1-6, 12-17, 19, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over US 2021/0062284 (A1) (also WO 2019/132128 (A1)) to Kim et al. (“Kim”).
US 2021/0062284 (A1) is a pre-grant publication of U.S. appl. serial no. 16/957,834, which is a 371 national stage application of PCT/KR2018/005622, published by WIPO as WO 2019/132128 (A1). The pre-grant publication will serve as an equivalent to and a translation of the WIPO publication.
Regarding claim 1, Kim discloses a non-oriented electrical steel. Abstract; para. [0001]. The steel includes the following elements in percent by weight (para. [0005], [0012], [0039]-[0044], [0063]-[0076]):
Element
Claim 1
US 2021/0062284 A1
Si
3.3 - 4.0
2.0 - 3.5
Al
0.4 - 1.5
0.3 - 3.5
Mn
0.2 - 1.0
0.2 - 4.5
C
0.0015 - 0.0040
equal to or less than 0.0040
N
0.0005 - 0.0020
equal to or less than 0.0040
S
0.0005 - 0.0025
equal to or less than 0.0040
Mo
0.005 - 0.01
equal to or less than 0.005
Ti
0.0005 - 0.0020
equal to or less than 0.0040
Nb
0.0005 - 0.0020
equal to or less than 0.0040
V
0.0005 - 0.0020
equal to or less than 0.0040
Fe & unavoidable
remainder
remainder
impurities
The average crystal grain size may be 50 µm to 95 µm (para. [0079]), which overlaps the claimed range.
With respect to claimed Equation 1 and taking the midpoints of C, N, Ti, Nb, V and the upper and midpoint of Mo, the calculated values of Equation 1 are about 2.125, which falls within the claimed range. In addition, the amounts of C, N, Mo, Ti, Nb, and V overlap the claimed quantities; therefore, the range defined by Equation 1 would also be overlapped.
The magnetism of the steel is improved by minimizing fine impurities, such as inclusions or precipitates. Para. [0003]. Elements that form inclusions and precipitates include C, S, N, Ti, Nb, or V, which form carbides and nitrides. Para. [0002], [0070]-[0074]. It is important to control the size of the inclusions by limiting the inclusions with a diameter of 0.5 µm to 1.0 µm occupying 40% by vol. or more of the entire inclusions (inclusions having a diameter of 500-1000 nm are 40% by volume or more of all inclusions). Para. [0013], [0077], [0091].
Because the objective is to coarsen inclusions and precipitates and minimize fine inclusions and precipitates (para. [0025], [0053], [0054]) and because inclusions that are 0.5-1.0 µm are 40% by volume or more of all inclusions, it follows that inclusions having a diameter less than 0.5 µm (less than 500 nm) should be minimized (distribution density of at least one of carbides, nitrides, and carbonitrides having particle sizes of 50 nm or less is 0.5 number/mm2 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 upper yield strength, Kim is silent regarding the percentage of 0.2% offset yield strength (Rp0.2) to the upper yield strength (ReH). However, it is well established that when a material is produced by a process that is identical or substantially identical to that of the claims and/or possesses a structure or composition that is identical or substantially identical to that of the claims, any claimed properties or functions are presumed to be inherent. Such a finding establishes a prima facie case of anticipation or obviousness. See MPEP § 2112.01. In the present case, the non-oriented electrical steel sheets of Kim have an alloy composition, grain size, and inclusion/precipitate distribution that meet the claimed steels. Thus, any claimed properties, such as offset yield strength and upper yield strength, would also be expected to exist in Kim’s steels due to the matching structure and composition.
Regarding claim 2, with respect to claimed Equation 2, the average grain size overlaps the claimed range and the distribution density of fine precipitates and inclusions should be minimized, as discussed above; therefore, the range defined by Equation 2 would also be overlapped.
Regarding claim 3, Kim discloses the presence of Sn 0.0030-0.2 wt.%, Sb 0.0030-0.15 wt.%, and P 0.0040-0.18 wt.% (para. [0045]-[0050]), which overlap the claimed ranges.
Regarding claim 4, Kim discloses Mg in an amount of equal to or less than 0.005 wt.% and Cu in an amount of equal to or less than 0.025 wt.% (para. [0076]), which overlap the claimed ranges.
Regarding claim 5, Kim discloses example specific resistivity values as high as 78 µΩ·cm (Table 2 – Classification No. 13), which falls within the claimed range. Other values in Table 2 exceed the claimed minimum of 50 µΩ·cm.
Regarding claim 6, Kim is silent regarding the density of the steel sheet. However, given that the proportions of alloying elements in Kim meet the claimed proportions, the density of Kim’s steels would be expected to meet the claimed density.
Regarding claims 12-17, 19, and 20, Kim discloses amounts of Si, Al, Mn, C, N, S, Ti, and Nb in percent by weight as follows (para. [0005], [0012], [0039]-[0044], [0063]-[0076]):
Element
Dependent Claims
US 2021/0062284 A1
Si
3.4 - 3.6 (clm 12)
2.0 - 3.5
Al
0.5 - 1.0 (clm 13)
0.3 - 3.5
Mn
0.3 - 0.7 (clm 14)
0.2 - 4.5
C
0.0020 - 0.0038 (clm 15)
equal to or less than 0.0040
N
0.0008 - 0.0018 (clm 16)
equal to or less than 0.0040
S
0.0010 - 0.0023 (clm 17)
equal to or less than 0.0040
Ti
0.0007 - 0.0018 (clm 19)
equal to or less than 0.0040
Nb
0.0007 - 0.0018 (clm 20)
equal to or less than 0.0040
The elements in Kim overlap or encompass the claimed amounts. 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.
Allowable Subject Matter
Claim 7 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter: In the instant specification, Table 3 shows properties of steels when Equation 1 is below 1.75 (Specimen Nos. A1, D2, and D6) and above 4.00 (Specimen Nos. B2 and C2). In these specimens, the 0.2% offset yield strength cannot reach a value of 440 MPa while simultaneously possessing a 0.2% offset yield strength (Rp0.2) that is 98.5% or more of the upper yield strength (ReH) (i.e., Rp0.2 / ReH ≥ 98.5%). When Equation 1 is less than 1.75, the steels have Rp0.2 / ReH values that fall below 98.5. When Equation 1 is more than 4.00, the steels have Rp0.2 / ReH values of 98.5 or more but cannot attain Rp0.2 values of 440 MPa or more.
Possessing both characteristics of Rp0.2 and Rp0.2 / ReH ensure that the steel is not deformed and destroyed by centrifugal force when rotated, which may cause a problem in durability, and for the steel to maintain its strength after being rotated at high speeds (p. 17, lines 14-24; p. 18, lines 1-14). Kim is silent regarding the 0.2% offset yield strength (Rp0.2) and does not teach or suggest satisfying Equation 1 while also meeting and achieving the claimed Rp0.2 and Rp0.2 / ReH values.
Response to Arguments
Applicant's arguments filed 06/30/2026 have been fully considered, but they are not persuasive.
Applicant argues that Kim does not recognize controlling the balance between Mo, Ti, Nb, and V and interstitial elements C and N as defined by Equation 1. Applicant states that Kim does not disclose or suggest controlling alloy composition together with average claimed grain size, claimed distribution density, and claimed relationship between 0.2% offset yield strength and upper yield strength.
In response, as an initial matter, Kim discloses a steel alloy composition that overlaps each of the ranges recited in claim 1 (para. [0005], [0012], [0039]-[0044], [0063]-[0076]). Kim also discloses the claimed grain size (para. [0079]). Furthermore, Kim expressly teaches that fine inclusions or precipitates should be minimized, as well as the purposeful control of inclusion size, thereby suggesting controlling fine inclusion density (para. [0002], [0003], [0013], [0025], [0053], [0054], [0070]-[0074], [0077], [0091].
With respect to the argument that the boundaries of Equation 1 are critical, the argument is not persuasive because the presumed criticality is not shown. Of the steels in Table 3 of the instant specification that fall outside Equation 1 (A1, B2, C2, D2, and D6), steels B2 and C2 have Rp0.2 / ReH values of 99.3% and 99.2 %, respectively, thereby exceeding the claimed value of 98.5% or more and meeting the claimed range. Therefore, the claimed endpoints of Equation 1 do not appear necessary or critical for achieving a Rp0.2 / ReH of 98.5% or more.
Applicant argues that the Office relies upon impermissible hindsight reconstruction to reject the claim.
In response, the Examiner respectfully disagrees. Equation 1 can be met by Kim by taking the midpoints of C, N, Ti, Nb, V and the upper and midpoint of Mo, which result in a calculated Equation 1 of about 2.125, which falls in the claimed range. In addition, the amounts of C, N, Mo, Ti, Nb, and V overlap the claimed quantities; therefore, the range defined by Equation 1 would also be overlapped. The use of midpoints as an approximation is a reasonable estimate because it does not favor one portion of the prior art range over another, although it should be understood that the entire span of a prior art range is recognized as valid. See MPEP §§ 2123, 2144.05(I).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to VANESSA T. LUK whose telephone number is (571)270-3587. The examiner can normally be reached Monday-Friday 9:30 AM - 4:30 PM ET.
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/VANESSA T. LUK/Primary Examiner, Art Unit 1733
September 18, 2026
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