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 .
Status of Claims
No amendments to the claims have been filed. Claims 1-16 and 21-24 remain pending and considered in this office action.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on March 16, 2026 was filed after the mailing date of the Non-Final Rejection on September 11, 2025. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Claim Interpretation
Claim 1 recites the limitation "cold rolling either once, or twice, or more” and also recites the limitation “final cold rolling”. The claims are interpreted such that a single step of cold rolling may read on both a "cold rolling either once, or twice, or more” and a “final cold rolling”.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1, 4-5, 12 and 21-24 are rejected under 35 U.S.C. 103 as being unpatentable over Tanaka (previously cited, US 20110042625 A1) in view of Takagi (previously cited, JP 11158590 A, English Translation provided) and Okubo (previously cited, WO 2016136095 A1, US 20180030558 A1 used as English Equivalent).
Regarding Claim 1, Tanaka discloses a method of manufacturing a non-oriented electrical steel sheet (Abstract), comprising:
a slab which has a chemical composition containing, in mass%,
Element
Claim 1
Tanaka, para. [0017]
C
0-0.005
0-0.06
P
0-0.08
0-0.3
Si
0-4
0-3.5
Mn
0-3
0.05-3
Al
0.23-2
0-2.5
S
0-0.005
0-0.04
N
0-0.005
0-0.02
Ti
0-0.003
*0<Nb/93+Zr/91+Ti/48+V/51-(C/12+N/14)<5x10-3
O
0-0.010
Silent (0%)
Nb
0-0.001
*0<Nb/93+Zr/91+Ti/48+V/51-(C/12+N/14)<5x10-3
Fe, inevitable impurities
Balance
Balance
Regarding O, Tanaka is silent towards this element and one of ordinary skill in the art would appreciate this element to be absent from the invention of Tanaka and inclusive of 0%.
Regarding Ti and Nb, one of ordinary skill in the art would appreciate that Tanaka discloses compositions which overlap with the claimed ranges. For example, Tanaka discloses compositions including one comprising 0.002% C, 0.002% N, 0.01% V, 0.01% Zr, 0.0005% Nb, and 0.001% Ti, which overlaps the claimed composition (see Table above) and meets the equation required by Tanaka (see Table 1 above and para. [0017]; the 0.002% C, 0.002% N, 0.01% V, 0.01% Zr, 0.0005% Nb and 0.001% Ti produce an equation value of 0.001).
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). See MPEP § 2144.05.I.
Tanaka further discloses subjecting the slab to hot rolling with or without performing hot-rolled sheet annealing, and then to cold rolling either once, or twice or more with intermediate annealing performed therebetween, and then to final annealing (para. [0100]), wherein
a finish temperature of the hot rolling is in the range of 700-900C (para. [0107]; para. [0121]), and
a final annealing temperature of 820C or less (para. [0131]).
Tanaka is silent towards heating rates during final annealing.
Okubo teaches using induction heating and an average heating rate from 600-700C of 50°C/s or higher, and using radiation heating and an average heating rate from 700-760C of 5°C/s or higher, in order to prevent the formation of {111} orientation grains during a rapid heating which is used to bring the steel quickly up to near the final annealing temperature, and to promote uniform heating close to and at the final annealing temperature, thereby improving texture in the finish annealing and increasing the magnetic flux density (para. [0010]-[0011] para. [0033]-[0036]; para. [0073]-[0077]). One of ordinary skill in the art would appreciate that these ranges overlap meet the claimed ranges of an average heating rate in final annealing from 600C to 720C of 50 °C/s or higher, and an average heating rate from 720C to 760C of 5°C/s or higher.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used rapid heating within the temperature range of 600C to 720C, with a heating rate of 50°C/s or higher, and induction heating in the range of 720C to 760C with an average heating rate of 5°C/s or higher, in final annealing, as taught by Okubo, for the invention disclosed by Tanaka. One would be motivated to do this in order to bring the steel quickly up to near the final annealing temperature, while preventing the formation of {111} orientation grains, and to promote uniform heating close and at the final annealing temperature, thereby improving texture in the finish annealing and increasing the magnetic flux density (see teachings by Okubo above).
Tanaka fails to disclose a recrystallization ratio of 80% or less before final cold rolling. However, Tanaka discloses wherein the material after final annealing comprises a recrystallization ratio of preferably 25% or less, or even more preferably 0% (para. [0096]). One of ordinary skill in the art would appreciate that in order to produce a steel strip, which has been cold-rolled and subjected to a final annealing, with 0% recrystallization, the steel strip would need to have a recrystallization ratio of 0% prior to cold-rolling and final annealing as well. One of ordinary skill in the art would appreciate that recovery and recrystallization are competing and mutually exclusive processes (one or the other occurs), such that to produce a recovered structure in the final product with no recrystallization, the entire process, and therefore the steel prior to final cold rolling and annealing, would necessarily be absent of any recrystallization (i.e., once recrystallization occurs, it persists until the final structure; see also para. [0132] of Tanaka, which describes final annealing temperature after cold rolling designed to suppress recrystallization, and wherein steel is a recovered steel and therefore not one which has undergone recrystallization – para. [0015] and para. [0018]).
Tanaka is silent towards the texture orientations of the steel prior to final cold rolling.
Takagi teaches wherein electrical steel used for rotating machines desirably have a random cubic texture, in which the orientation of the rolled surface is {100} and the orientation of the easy magnetization axis is randomly distributed in the plane (para. [0005]). Takagi teaches obtaining an intensity of 3 or more for the orientations {100}<011> and {100}<001> in a hot-rolled sheet (and prior to cold-rolling) in order to achieve this and to provide improved average magnetic flux density in all in-plane directions (para. [0005]; Abstract; para. [0024]; para. [0016]-[0019]; para. [0041]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have obtained a hot-rolled sheet with a {100}<011> intensity of 3 or more (and within the claimed range of 8 or less) prior to final cold rolling, as taught by Takagi, for the invention disclosed by Tanaka, in order to comprise improved average magnetic flux in all in-plane directions and random cubic texture, features advantageous for a rotating machine and therefore the rotating machine disclosed by Tanaka (see teaching above by Takagi, see Abstract of Tanaka wherein steel is used for a rotating machine).
Takagi does not disclose that the orientation intensities are at a ¼ layer thickness; however, it would be obvious to obtain the desired orientation intensities of Takagi throughout the steel layer, and therefore at a ¼ layer, in order to produce the desired effects (improved magnetic flux in all in-plane directions, random cubic texture and randomly distributed easy axis of magnetization) for the entirety of the thickness of the steel sheet.
Regarding intensity ranges and recrystallization ratios, 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). See MPEP § 2144.05.I.
Regarding Claim 4, Tanaka discloses wherein the slab further contains, in mass%, either or both of Sn and Sb of 0.005-0.20%, respectively (para. [0089]). 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). See MPEP § 2144.05.I.
Regarding Claim 5 and Claim 12, Tanaka discloses wherein the slab further contains, in mass%, at least one selected from the group consisting of Ca: 0.0005-0.010%, Mg: 0.0001-0.0050%, and REM: 0.001-0.020% (para. [0092]). 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). See MPEP § 2144.05.I.
Regarding Claim 21, Tanaka discloses wherein the material before final cold rolling has a recrystallization ratio of less than 50% (see Claim 1 rejection above and para. [0096] of Tanaka, wherein a cold rolled and annealed steel with 0% recrystallization would also comprise a structure with 0% (and therefore less than 50%) recrystallization before final cold rolling).
Regarding Claim 22, Okubo discloses wherein the heating rate from 700-760C is 5C/s or higher, which reads on the claimed range of 10C/s or less (see Claim 1 rejection above, Okubo, para. [0011]). 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). See MPEP § 2144.05.I.
Regarding Claim 23, Tanaka discloses a method of manufacturing a non-oriented electrical steel sheet (Abstract), comprising:
a slab which has a chemical composition containing, in mass%,
Element
Claim 24
Tanaka, para. [0017]
C
0-0.005
0-0.06
P
0-0.08
0-0.3
Si
0-4
0-3.5
Mn
0-3
0.05-3
Al
0-2
0-2.5
S
0-0.005
0-0.04
N
0-0.005
0-0.02
Ti
0-0.003
*0<Nb/93+Zr/91+Ti/48+V/51-(C/12+N/14)<5x10-3
O
0-0.010
Silent (0%)
Nb
0-0.001
*0<Nb/93+Zr/91+Ti/48+V/51-(C/12+N/14)<5x10-3
Fe, inevitable impurities
Balance
Balance
optionally at least one of:
Tanaka, para. [0089]-[0092]
Sb
0.005-0.20
0.0005-0.05
Ca
0.0005-0.010
0.0001-0.03
Mg
0.0001-0.0050
0.0001-0.02
REM
0.001-0.020
0.0001-0.01
Regarding O, Tanaka is silent towards this element and one of ordinary skill in the art would appreciate this element to be absent from the invention of Tanaka and inclusive of 0%.
Regarding Ti and Nb, one of ordinary skill in the art would appreciate that Tanaka discloses compositions which overlap with the claimed ranges. For example, Tanaka discloses compositions including one comprising 0.002% C, 0.002% N, 0.01% V, 0.01% Zr, 0.0005% Nb, and 0.001% Ti, which overlaps the claimed composition (see Table above) and meets the equation required by Tanaka (see Table 1 above and para. [0017]; the 0.002% C, 0.002% N, 0.01% V, 0.01% Zr, 0.0005% Nb and 0.001% Ti produce an equation value of 0.001).
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). See MPEP § 2144.05.I.
Tanaka further discloses subjecting the slab to hot rolling with or without performing hot-rolled sheet annealing, and then to cold rolling either once, or twice or more with intermediate annealing performed therebetween, and then to final annealing (para. [0100]), wherein
a finish temperature of the hot rolling is in the range of 700-900C (para. [0107]; para. [0121]), and
a final annealing temperature of 820C or less (para. [0131]).
Tanaka is silent towards heating rates during final annealing.
Okubo teaches using induction heating and an average heating rate from 600-700C of 50°C/s or higher, and using radiation heating and an average heating rate from 700-760C of 5°C/s or higher, in order to prevent the formation of {111} orientation grains during a rapid heating which is used to bring the steel quickly up to near the final annealing temperature, and to promote uniform heating close and at the final annealing temperature, thereby improving texture in the finish annealing and increasing the magnetic flux density (para. [0010]-[0011] para. [0033]-[0036]; para. [0073]-[0077]). One of ordinary skill in the art would appreciate that these ranges overlap meet the claimed ranges of an average heating rate in final annealing from 600C to 720C of 50 °C/s or higher, and an average heating rate from 720C to 760C of 5°C/s or higher.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used rapid heating within the temperature range of 600C to 720C, with a heating rate of 50°C/s or higher, and induction heating in the range of 720C to 760C with an average heating rate of 5°C/s or higher, in final annealing, as taught by Okubo, for the invention disclosed by Tanaka. One would be motivated to do this in order to bring the steel quickly up to near the final annealing temperature, while preventing the formation of {111} orientation grains, and to promote uniform heating close and at the final annealing temperature, thereby improving texture in the finish annealing and increasing the magnetic flux density (see teachings by Okubo above).
Tanaka fails to disclose a recrystallization ratio of 80% or less before final cold rolling. However, Tanaka discloses wherein the material after final annealing comprises a recrystallization ratio of preferably 25% or less, or even more preferably 0% (para. [0096]). One of ordinary skill in the art would appreciate that in order to produce a steel strip, which has been cold-rolled and subjected to a final annealing, with 0% recrystallization, the steel strip would need to have a recrystallization ratio of 0% prior to cold-rolling and final annealing as well. One of ordinary skill in the art would appreciate that recrystallization occurs as a result of annealing at specific temperatures after cold-rolling (see also para. [0132] of Tanaka, which describes final annealing temperature after cold rolling designed to suppress recrystallization, and wherein steel is a recovered steel and therefore not one which has undergone recrystallization – para. [0015] and para. [0018]).
Tanaka is silent towards the texture orientations of the steel prior to final cold rolling.
Takagi teaches wherein electrical steel used for rotating machines desirably have a random cubic texture, in which the orientation of the rolled surface is {100} and the orientation of the easy magnetization axis is randomly distributed in the plane (para. [0005]). Takagi teaches obtaining an intensity of 3 or more for the orientations {100}<011> and {100}<001> in a hot-rolled sheet (and prior to cold-rolling) in order to achieve this and to provide improved average magnetic flux density in all in-plane directions (para. [0005]; Abstract; para. [0024]; para. [0016]-[0019]; para. [0041]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have obtained a hot-rolled sheet with a {100}<011> intensity of 3 or more (and within the claimed range of 8 or less) prior to final cold rolling, as taught by Takagi, for the invention disclosed by Tanaka, in order to comprise improved average magnetic flux in all in-plane directions and random cubic texture, features advantageous for a rotating machine and therefore the rotating machine disclosed by Tanaka (see teaching above by Takagi, see Abstract of Tanaka wherein steel is used for a rotating machine).
Takagi does not disclose that the orientation intensities are at a ¼ layer thickness; however, it would be obvious to obtain the desired orientation intensities of Takagi throughout the steel layer, and therefore at a ¼ layer, in order to produce the desired effects (improved magnetic flux in all in-plane directions, random cubic texture and randomly distributed easy axis of magnetization) for the entirety of the thickness of the steel sheet.
Regarding intensity ranges and recrystallization ratios, 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). See MPEP § 2144.05.I.
Regarding Claim 24, Tanaka discloses a method of manufacturing a non-oriented electrical steel sheet (Abstract), comprising:
a slab which has a chemical composition containing, in mass%,
Element
Claim 24
Tanaka, para. [0017]
C
0-0.005
0-0.06
P
0-0.08
0-0.3
Si
0-4
0-3.5
Mn
0-3
0.05-3
Al
0-2
0-2.5
S
0-0.005
0-0.04
N
0-0.005
0-0.02
Ti
0-0.003
*0<Nb/93+Zr/91+Ti/48+V/51-(C/12+N/14)<5x10-3
O
0-0.010
Silent (0%)
Nb
0-0.001
*0<Nb/93+Zr/91+Ti/48+V/51-(C/12+N/14)<5x10-3
Fe, inevitable impurities
Balance
Balance
optionally at least one of:
Tanaka, para. [0089]-[0092]
Sn
0.005-0.20
0.001-0.5
Sb
0.005-0.20
0.0005-0.05
Ca
0.0005-0.010
0.0001-0.03
Mg
0.0001-0.0050
0.0001-0.02
REM
0.001-0.020
0.0001-0.01
Regarding O, Tanaka is silent towards this element and one of ordinary skill in the art would appreciate this element to be absent from the invention of Tanaka and inclusive of 0%.
Regarding Ti and Nb, one of ordinary skill in the art would appreciate that Tanaka discloses compositions which overlap with the claimed ranges. For example, Tanaka discloses compositions including one comprising 0.002% C, 0.002% N, 0.01% V, 0.01% Zr, 0.0005% Nb, and 0.001% Ti, which overlaps the claimed composition (see Table above) and meets the equation required by Tanaka (see Table 1 above and para. [0017]; the 0.002% C, 0.002% N, 0.01% V, 0.01% Zr, 0.0005% Nb and 0.001% Ti produce an equation value of 0.001).
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). See MPEP § 2144.05.I.
Tanaka further discloses subjecting the slab to hot rolling with or without performing hot-rolled sheet annealing, and then to cold rolling either once, or twice or more with intermediate annealing performed therebetween, and then to final annealing (para. [0100]), wherein
a finish temperature of the hot rolling is in the range of 700-900C (para. [0107]; para. [0121]), and
a final annealing temperature of 820C or less (para. [0131]).
Tanaka is silent towards heating rates during final annealing.
Okubo teaches using induction heating and an average heating rate from 600-700C of 50°C/s or higher, and using radiation heating and an average heating rate from 700-760C of 5°C/s or higher, in order to prevent the formation of {111} orientation grains during a rapid heating which is used to bring the steel quickly up to near the final annealing temperature, and to promote uniform heating close and at the final annealing temperature, thereby improving texture in the finish annealing and increasing the magnetic flux density (para. [0010]-[0011] para. [0033]-[0036]; para. [0073]-[0077]). One of ordinary skill in the art would appreciate that these ranges overlap meet the claimed ranges of an average heating rate in final annealing from 600C to 720C of 50 °C/s or higher, and an average heating rate from 720C to 760C of 5°C/s or higher.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used rapid heating within the temperature range of 600C to 720C, with a heating rate of 50°C/s or higher, and induction heating in the range of 720C to 760C with an average heating rate of 5°C/s or higher, in final annealing, as taught by Okubo, for the invention disclosed by Tanaka. One would be motivated to do this in order to bring the steel quickly up to near the final annealing temperature, while preventing the formation of {111} orientation grains, and to promote uniform heating close and at the final annealing temperature, thereby improving texture in the finish annealing and increasing the magnetic flux density (see teachings by Okubo above).
Tanaka fails to disclose a recrystallization ratio of 50% or less before final cold rolling. However, Tanaka discloses wherein the material after final annealing comprises a recrystallization ratio of preferably 25% or less, or even more preferably 0% (para. [0096]). One of ordinary skill in the art would appreciate that in order to produce a steel strip, which has been cold-rolled and subjected to a final annealing, with 0% recrystallization, the steel strip would need to have a recrystallization ratio of 0% prior to cold-rolling and final annealing as well. One of ordinary skill in the art would appreciate that recrystallization occurs as a result of annealing at specific temperatures after cold-rolling (see also para. [0132] of Tanaka, which describes final annealing temperature after cold rolling designed to suppress recrystallization, and wherein steel is a recovered steel and therefore not one which has undergone recrystallization – para. [0015] and para. [0018]).
Tanaka is silent towards the texture orientations of the steel prior to final cold rolling.
Takagi teaches wherein electrical steel used for rotating machines desirably have a random cubic texture, in which the orientation of the rolled surface is {100} and the orientation of the easy magnetization axis is randomly distributed in the plane (para. [0005]). Takagi teaches obtaining an intensity of 3 or more for the orientations {100}<011> and {100}<001> in a hot-rolled sheet (and prior to cold-rolling) in order to achieve this and to provide improved average magnetic flux density in all in-plane directions (para. [0005]; Abstract; para. [0024]; para. [0016]-[0019]; para. [0041]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have obtained a hot-rolled sheet with a {100}<011> intensity of 3 or more (and within the claimed range of 8 or less) prior to final cold rolling, as taught by Takagi, for the invention disclosed by Tanaka, in order to comprise improved average magnetic flux in all in-plane directions and random cubic texture, features advantageous for a rotating machine and therefore the rotating machine disclosed by Tanaka (see teaching above by Takagi, see Abstract of Tanaka wherein steel is used for a rotating machine).
Takagi does not disclose that the orientation intensities are at a ¼ layer thickness; however, it would be obvious to obtain the desired orientation intensities of Takagi throughout the steel layer, and therefore at a ¼ layer, in order to produce the desired effects (improved magnetic flux in all in-plane directions, random cubic texture and randomly distributed easy axis of magnetization) for the entirety of the thickness of the steel sheet.
Regarding intensity ranges and recrystallization ratios, 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). See MPEP § 2144.05.I.
Claims 2, 7, 10 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Tanaka (previously cited, US 20110042625 A1) in view of Takagi (previously cited, JP 11158590 A, English Translation provided) and Okubo (previously cited, WO 2016136095 A1, US 20180030558 A1 used as English Equivalent), as applied to Claim 1 above, respectively, in further view of Paolinelli (previously cited, “The Influence of Hot Rolling Finishing Temperature On the Structure and Magnetic Properties of 2.0%Si Non Oriented Silicon Steel”) and Cunha (previously cited, “Effect of Hot Rolling Temperature on the Structure and Magnetic Properties of High Permeability Non-Oriented Silicon Steel”).
Regarding Claim 2, Tanaka is silent towards a y phase ratio in the slab at the slab heating temperature.
However, Tanaka discloses the same composition as claimed, and wherein the slab comprises a slab heating temperature of 1100-1300C, which overlaps the claimed invention (para. [0025]; see instant specification, para. [0035]). One of ordinary skill in the art would appreciate that the y phase amount in the slab results from the chemical composition of the slab and the slab heating temperature, with higher slab heating temperatures producing larger amounts of y phase for a particular composition. Thus, because the composition and the slab heating temperatures of Tanaka are the same (or higher) as the instant invention, one of ordinary skill in the art would appreciate that the steel slab of Tanaka comprise at least 30% or more y phase at the slab heating temperature, as claimed.
Tanaka further discloses rough rolling (para. [0025]), but fails to disclose reverse rolling.
Paolinelli teaches wherein hot rolling comprises rough rolling followed by reverse rolling in order to obtain desired thicknesses (pg. 788, Experimental procedure), and Cunha teaches wherein reversible rough rolling is included for industrial hot rolling of steel (pg. 421, Col. 2).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used reverse rolling, as taught by Paolinelli, including a reverse rough rolling in the hot rolling, as taught by Cunha, for the invention disclosed by Tanaka, in order to obtain non-oriented steel at desired thicknesses and with an industrial level of production.
Regarding Claim 7, Tanaka discloses wherein the slab further contains, in mass%, either or both of Sn and Sb of 0.005-0.20%, respectively (para. [0089]). 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). See MPEP § 2144.05.I.
Regarding Claim 10 and Claim 14, Tanaka discloses wherein the slab further contains, in mass%, at least one selected from the group consisting of Ca: 0.0005-0.010%, Mg: 0.0001-0.0050%, and REM: 0.001-0.020% (para. [0092]). 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). See MPEP § 2144.05.I.
Claims 3, 8, 11 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Tanaka (previously cited, US 20110042625 A1) in view of Takagi (previously cited, JP 11158590 A, English Translation provided) and Okubo (previously cited, WO 2016136095 A1, US 20180030558 A1 used as English Equivalent), as applied to Claim 1 above, respectively, in further view of Hiura (previously cited, JP 4337146 B2, English Machine Translation provided).
Regarding Claim 3, Tanaka is silent towards a y phase ratio in the slab at the slab heating temperature.
However, Tanaka discloses the same composition as claimed, and wherein the slab comprises a slab heating temperature of 1100-1300C, which overlaps the claimed invention (para. [0025]; see instant specification, para. [0035]). One of ordinary skill in the art would appreciate that the y phase amount in the slab results from the chemical composition of the slab and the slab heating temperature, with higher slab heating temperatures producing larger amounts of y phase for a particular composition. Thus, because the composition and the slab heating temperatures of Tanaka are the same (or higher) as the instant invention, one of ordinary skill in the art would appreciate that the steel slab of Tanaka comprise at least 30% or more y phase at the slab heating temperature, as claimed.
Tanaka fails to disclose a reheating treatment is performed to raise a material temperature by 20°C or more between a start and an end of the hot rolling.
Hiura teaches a continuous hot-rolling, wherein a reheating treatment is performed to raise a material temperature by 20°C or more after rough hot rolling and before finish hot rolling, in order to reduce iron core loss and magnetic anisotropy (para. [0011]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a hot-rolling process including rough rolling and finish rolling, and one which is continuous and includes a reheating treatment to raise a material temperature by 20°C or more between a start and an end of the hot rolling, as taught by Hiura, for the invention disclosed by Tanaka. One would be motivated to do this in order to efficiently obtain desired hot-rolling thicknesses while reducing iron core loss and magnetic anisotropy (see teaching by Hiura above).
Regarding Claim 8, Tanaka discloses wherein the slab further contains, in mass%, either or both of Sn and Sb of 0.005-0.20%, respectively (para. [0089]). 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). See MPEP § 2144.05.I.
Regarding Claim 11 and Claim 15, Tanaka discloses wherein the slab further contains, in mass%, at least one selected from the group consisting of Ca: 0.0005-0.010%, Mg: 0.0001-0.0050%, and REM: 0.001-0.020% (para. [0092]). 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). See MPEP § 2144.05.I.
Claims 6, 9, 13 and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Tanaka (previously cited, US 20110042625 A1) in view of Takagi (previously cited, JP 11158590 A, English Translation provided), Okubo (previously cited, WO 2016136095 A1, US 20180030558 A1 used as English Equivalent), Paolinelli (previously cited, “The Influence of Hot Rolling Finishing Temperature On the Structure and Magnetic Properties of 2.0%Si Non Oriented Silicon Steel”) and Cunha (previously cited, “Effect of Hot Rolling Temperature on the Structure and Magnetic Properties of High Permeability Non-Oriented Silicon Steel”), as applied to Claim 2 above, in further view of Hiura (previously cited, JP 4337146 B2, English Machine Translation provided).
Regarding Claim 6, Tanaka is silent towards a y phase ratio in the slab at the slab heating temperature.
However, Tanaka discloses the same composition as claimed, and wherein the slab comprises a slab heating temperature of 1100-1300C, which overlaps the claimed invention (para. [0025]; see instant specification, para. [0035]). One of ordinary skill in the art would appreciate that the y phase amount in the slab results from the chemical composition of the slab and the slab heating temperature, with higher slab heating temperatures producing larger amounts of y phase for a particular composition. Thus, because the composition and the slab heating temperatures of Tanaka are the same (or higher) as the instant invention, one of ordinary skill in the art would appreciate that the steel slab of Tanaka comprise at least 30% or more y phase at the slab heating temperature, as claimed.
Tanaka fails to disclose a reheating treatment is performed to raise a material temperature by 20°C or more between a start and an end of the hot rolling.
Hiura teaches a continuous hot-rolling, wherein a reheating treatment is performed to raise a material temperature by 20°C or more after rough hot rolling and before finish hot rolling, in order to reduce iron core loss and magnetic anisotropy (para. [0011]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a hot-rolling process including rough rolling and finish rolling, and one which is continuous and includes a reheating treatment to raise a material temperature by 20°C or more between a start and an end of the hot rolling, as taught by Hiura, for the invention disclosed by Tanaka. One would be motivated to do this in order to efficiently obtain desired hot-rolling thicknesses while reducing iron core loss and magnetic anisotropy (see teaching by Hiura above).
Regarding Claim 9, Tanaka discloses wherein the slab further contains, in mass%, either or both of Sn and Sb of 0.005-0.20%, respectively (para. [0089]). 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). See MPEP § 2144.05.I.
Regarding Claim 13 and Claim 16, Tanaka discloses wherein the slab further contains, in mass%, at least one selected from the group consisting of Ca: 0.0005-0.010%, Mg: 0.0001-0.0050%, and REM: 0.001-0.020% (para. [0092]). 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). See MPEP § 2144.05.I.
Response to Arguments
Applicant’s arguments, filed June 9, 2025, with respect to Claim 1, and dependent claims thereof, rejected under 35 U.S.C. 103 over Tanaka in view of Takagi and Okubo, have been fully considered but are respectfully not found persuasive.
Regarding Tanaka:
Applicant argues that Examiner takes the position that cold rolling has no effect on recrystallization structure and that a structure that has gone through recrystallization cannot become a non-crystallized structure, and thus that the recrystallization amount of a non-oriented electrical steel sheet is accumulated through each of the processing steps. Applicant disagrees that recrystallization amounts are accumulated, and argues that a recrystallized structure may be undone.
Applicant further argues that a deformed microstructure means a non-recrystallized microstructure with 0% recrystallization, and that recovered microstructures have 0% recrystallization. Applicant argues that final/finish annealing recrystallizes the microstructure which then progresses to grain growth.
Therefore, Applicant argues that cold rolling after hot rolling will initiate a microstructure with 0% recrystallization and that any recrystallization after cold rolling depends on the final annealing. Applicant also argues however that a steel sheet subjected to cold rolling and finish rolling may have a lower recrystallization amount after finish annealing.
Applicant argues that Takana2009 shows a higher amount of recrystallization before cold rolling than after finish annealing, and argues this demonstrates that cold rolling removes recrystallization and that recrystallization does not accumulate. Applicant argues therefore that 0% recrystallization after final annealing does not mean 0% recrystallization before cold rolling.
These arguments are not found persuasive.
Applicant and Examiner agree that recovered microstructures have 0% recrystallization and agree that annealing produces recrystallization. However, no evidence is provided that suggests that deformed structures are synonymous with a non-recrystallized structure, and no evidence is provided to suggest that recrystallization occurring as a result of hot rolling is eliminated by cold rolling. A deformed, recrystallized grain is still a recrystallized grain. The assertion that cold rolling deformation eliminates an amount of recrystallization is fundamentally incorrect.
Applicant cites Tanaka2009 (cited by Examiner in previous Non-Final Rejection), and references (exhibit A and exhibit B), but neither of these references recite where cold rolling eliminates an amount recrystallization, nor wherein another process is capable of eliminating recrystallization. One of ordinary skill in the art would appreciate recrystallization is only removed by remelting. Further, the interpretation that Tanaka2009 demonstrates wherein cold rolling removes recrystallization produced from hot rolling is incorrect. Tanaka2009 makes no such assertion and does not measure recrystallization ratio before and after cold-rolling. The portions of the table that show a lower recrystallization ratio after finish annealing than before cold rolling appear to be mistakes in the patent application, as Tanaka2009 specifically states that recrystallization proceeds during the soaking step ([0013]; [0068]), and one of ordinary skill in the art would understand that cold-rolling does not reduce recrystallization ratio. In other words, recrystallization is a permanent process to a solidified (non-remelted) alloy structure and only succeeded by grain growth and secondary recrystallization, which is well-known to those of ordinary skill in the art.
Additionally, Applicant repeatedly refers to the term ‘recrystallization structure’, however the claims do not recite recrystallization structure, only ‘recrystallization ratio’, and therefore the arguments are not commensurate in scope with the claims. Further, the Examiner does not suggest that cold rolling has no impact on recrystallization grain structure, as deformation and introduction of dislocations would occur. Changes to recrystallization grain structure is different than changes to the claimed recrystallization ratio amount.
Regarding Takagi:
Applicant argues that there is no motivation to combine Takagi with Tanaka with a reasonable expectation of success because Takagi teaches wherein the textural effect can only be obtained with 0.2-1.2% P.
This argument is not found persuasive.
Takagi teaches at least 0.2% P in order to increase specific resistance and reduce the slip current loss (para. [0021]). Paragraph [0021] of Takagi does not mention the orientation feature, and Takagi does not disclose wherein the amount of P is critical to achieving or is correlated to the taught orientation feature. Takagi demonstrate that the texture orientations are achievable with values of P less than 0.2wt% (Table 2, example no. 3, steel (B) which comprises 0.001% P and an orientation intensity greater than 3), and therefore there is a reasonable expectation of success for steels with less than 0.2% P and further less than 0.08% P as claimed.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Schoen (previously cited, US 20040016530 A1): teaches an overlapping composition (para. [0013]-[0019]), wherein the amount of recrystallization before cold rolling or finish annealing is preferably less than 10%, and wherein the steel strip more preferably is substantially free of recrystallization, in order to preserve <100> texture of the as cast strip and improve magnetic properties (para. [0089]; para. [0100]).
Murakawa (previously cited, US 20220349037 A1): teaches an intensity of 5 or more at a sheet surface for the {100}<011> orientation in order to increase the magnetic flux density in a direction 45 degrees to the rolling direction, and therefore increase the magnetic flux density as a whole on the whole circumferential average in a sheet surface (para. [0051]).
Kishio (previously cited, JP H0463228 A): teaches wherein hot-rolling heating and finishing temperatures are 1100C or less, and wherein the finishing temperature is preferably 820-870C (Abstract; para. [0074]; see Fig. 5). Kishio teaches wherein these hot-rolling temperatures and the finishing temperatures of 820-870C produce lower intensities of the (100) crystal grains, thereby improving magnetic properties (para. [0078]; para. [0105]; Fig. 5. Kishio teaches wherein intensities for (001) grains are lower than 8 at all distances from the surface layer (see Fig. 5).
Jin (previously cited, “Effect of Hot-rolled microstructure on the recrystallization Texture of Cold-rolled non-oriented electrical steel’): teaches a hot-rolled grain structure formed from a hot-roll finishing temperature of 850C, wherein the intensity of the {100}<011> orientation is 8 or less (see Fig. 2, all intensities are less than 5). Jin further teaches that hot-rolled samples which are only partially recrystallized and not equiaxed by normalizing heat treatment show lower rotated cube texture prior to cold rolling (Fig. 2; hot-rolled sample comprises lower intensity of rotated cube texture than hot-rolled and equiaxed and normalized structure; rotated cube is the claimed {100}<011> orientation; see intensities at top right and top left corners which designate the location of the claimed orientation).
Jin teaches wherein the fully recrystallized sample comprises a larger intensity of {100}<011> texture and therefore showed weakened {100}<uvw> texture after cold rolling and annealing, which is detrimental to the magnetic properties of cold-rolled non-oriented silicon steel (Abstract).
Zaizen (previously cited, WO 2017086036 A1, US 20180327883 used as English Translation): teaches a heating rate from 600-740C of 50C/s or more, and an average heating rate from 740-920C is 10C/s, in order to increase magnetic flux density (para. [0017]; para. [0029]; para. [0034]; para. [0082]).
Tanaka2009 (JP 2009299102 A, English Machine Translation provided): teaches wherein the recrystallization ratio in the steel is 30% or less in order to suppress fatigue fracture, and further, the recrystallization ratio before cold rolling is 40% or less, preferably 0% (is preferably a recovered structure), in order to improve the tensile strength in the 45 direction from the rolling direction (para. [0056]; [0071]).
THIS ACTION IS MADE FINAL. 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 CATHERINE P SMITH whose telephone number is (303)297-4428. The examiner can normally be reached Monday - Friday 9:00-4:00 MT.
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CATHERINE P. SMITH
Patent Examiner
Art Unit 1735
/CATHERINE P SMITH/Examiner, Art Unit 1735
/KEITH WALKER/Supervisory Patent Examiner, Art Unit 1735