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 .
Priority
Receipt is acknowledged of a certified copy of JP 2020-178302 filed October 23, 2020 as required by 37 CFR 1.55. Receipt is also acknowledged of WO 2022/085788, the WIPO publication of PCT/JP 2021/039115 filed October 22, 2021.
Response to Restriction Election
Applicant’s election without traverse of Group I, claims 1-4, 7, and 8, drawn to a ferritic stainless steel composition with surface oxides in the reply filed on December 1, 2025 is acknowledged.
Claims 5, 6, and 9-14 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected inventive group, there being no allowable generic or linking claim.
Claim Status
This Office Action is in response to Applicant’s Claims filed April 19, 2023.
Claims Filing Date
April 19, 2023
Amended
3, 4, 6
New
7-14
Pending
1-14
Withdrawn
5, 6, 9-14
Under Examination
1-4, 7, 8
Claim Rejections - 35 USC § 103
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.
Claims 1-4, 7, and 8 are rejected under 35 U.S.C. 103 as being unpatentable over Ugi (JP H06-235100 machine translation) in view of JP ‘880 (JP H05-271880 machine translation).
Regarding claim 1, Ugi discloses a ferritic stainless steel ([0001]) with an overlapping composition ([0006]-[0013]). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. MPEP 2144.05(I).
Ugi is silent to 0.01 mass% or more and 0.50 mass% or less of Ni, 0.002 mass% or more and 0.200 mass% or less of Al, and 0 mass% or more and 0.500 mass% or less Ti.
JP ‘880 discloses a ferritic stainless steel ([0001], [0007]) with 0.01 mass% or more and 0.50 mass% or less of Ni (1.0% or less) ([0019]), 0.002 mass% or more and 0.200 mass% or less of Al (0.01 to 0.5%) ([0022]), and 0 mass% or more and 0.500 mass% or less Ti (0.05 to 0.3% Ti) ([0024]).
It would have been obvious to one of ordinary skill in the art in the ferritic stainless steel of Ugi to include 1.0% or less Ni to improve toughness without increasing the cost (JP ‘880 [0019]) and 0.01 to 0.5% Al with 0.05 to 0.3% Ti to inhibit corrosion by forming an Al-enriched layer in the passivation film by annealing and pickling that improves weather resistance without deteriorating surface quality, weldability, and localized corrosion (JP ‘880 [0022], [0024]). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. MPEP 2144.05(I).
Element
Claim 1
Ugi Disclosure
Ugi Citation
Si
0.05 to 2.50
0.3 to 3.0
[0008]
Mn
0.05 to 1.50
0.3 or less
[0009]
C
0.025 or less
0.1 or less
[0007]
P
0.040 or less
-
-
S
0.003 or less
-
-
N
0.025 or less
Below 0.1
[0012]
Ni
0.01 to 0.50
-
-
Cr
10.50 to 25.00
11 to 30
[0010]
Cu
0.01 to 1.80
0.1 to 1.0
[0011]
Al
0.002 to 0.200
-
-
Nb
0.001 to 1.00
0.1 to 1.0
[0013]
Fe
Remainder
Balance
[0006]
Ugi discloses at least one type of oxides of oxides containing 5 mass% or more of Al and oxides containing 5 mass% or more of Si are present on a surface (producing and concentrating SiO2, silicon oxide, on the surface) ([0005], [0008], [0014]-[0017]).
JP ‘880 discloses at least one type of oxides of oxides containing 5 mass% or more of Al and oxides containing 5 mass% or more of Si are present on a surface (Al-enriched layer is easily formed in the passivation film) ([0022], [0024], [0029]-[0033]).
It would have been obvious to one of ordinary skill in the art for the steel of Ugi in view of JP ‘880 to include both silicon oxide and Al-enriched oxide in the passive layer because the composition and processing forms both (Ugi [0005], [0008], [0014]-[0017]; JP ‘880 [0022], [0024], [0029]-[0033]).
The limitation of among the oxides present on the surface, the number of oxides having a diameter D of 0.1 um or more and 2.0 um or less being 10 or more per 93 um2, the diameter D being represented by the following formula (1) D= (Dmax + Dmin)/2 -- (1) in the formula (1), Dmax is a maximum diameter of the oxide on the surface, and Dmin is a minimum diameter of the oxide on the surface, has been considered and determined to recite a property that results from the claimed ferritic steel composition undergoing applicant’s disclosed process (applicant’s specification [0068]-[0080]), where the final annealing step form internal oxides of Al, Si, or the like, and outer layer oxides (applicant’s specification [0074]) and the nitric acid electrolysis removes oxides adhering to the surface, while the internal oxides remain (applicant’s specification [0075]).
Ugi discloses a process that is substantially similar to that disclosed by application (Ugi [0015]-[0019]), including overlapping conditions of final (bright) annealing followed by nitric acid electrolysis (Ugi [0015]-[0016]) to concentrate silicon oxide on the surface (Ugi [0005], [0008], [0014]-[0017]). The prior art discloses a substantially similar composition (Ugi [0006]-[0013]; JP ‘880 [0019], [0022], [0024]) and substantially similar processing (Ugi [0015]-[0019]). Therefore, the properties of the claimed invention naturally flow from the disclosure of the prior art, including among the oxides present on the surface, the number of oxides having a diameter D of 0.1 um or more and 2.0 um or less being 10 or more per 93 um2, the diameter D being represented by the following formula (1) D= (Dmax + Dmin)/2 -- (1) in the formula (1), Dmax is a maximum diameter of the oxide on the surface, and Dmin is a minimum diameter of the oxide on the surface. “[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” MPEP 2144.05(II)(A).
Applicant’s Disclosed Process
[0068]-[0080]
Ugi’s Disclosed Process
[0015]-[0019]
Pretreatment
1100-1300°C
Casting
-
Hot Rolling
Hot Rolling
Annealing, optional
Annealing
First Pickling
HCl or HNO3+HF
Descaling
Cold Rolling
Cold Rolling
Final Annealing
900-1100°C
30-90 seconds
Bright Annealing
950-1050°C
10-100 seconds
Nitric Acid Electrolysis
100-150 g/L
50-70°C
100-150 mA/cm2
60-120 seconds
Nitric Acid Electrolysis
1-30 wt% (10-300 g/L)
10-60°C
1-100 coulombs/dm2 (10-1000 mA/cm2)
-
Final Pickling
HNO3+HF
-
Regarding claim 2, regarding the surface, CIE1976 luminosity L* that is measured using a D65 light source in a diffuse lighting mode by receiving light in a direction at 80 with respect to a normal line to the surface at a visual field angle of 100 visual field for a measurement time of one second being 60 or more has been considered and determined to recite a property that results from the claimed ferritic steel composition undergoing applicant’s disclosed process (applicant’s specification [0068]-[0080]), where the nitric acid concentration during nitric acid electrolysis controls the luminosity (applicant’s specification [0076]) and the final pickling step of immersion in a liquid mixture of nitric acid and hydrofluoric acid improves the luminosity (applicant’s specification [0080]).
The process of Ugi ([0015]-[0019]) discloses an overlapping nitric acid concentration ([0017]), but is silent to final pickling.
JP ‘880 discloses annealing, nitric acid electrolysis, then final pickling in a mixed acid solution of nitric acid and hydrofluoric acid ([0031]-[0033]).
It would have been obvious to one of ordinary skill in the art in the process of Ugi to final pickle in a mixed acid solution of nitric acid and hydrofluoric acid to remove porous oxide scale to achieve sufficient corrosion and weather resistance (JP ‘880 [0033]).
Therefore, the prior art discloses a substantially similar composition (Ugi [0006]-[0013]; JP ‘880 [0019], [0022], [0024]) and substantially similar processing (Ugi [0015]-[0019]; JP ‘880 [0031]-[0033]), such that the properties of the claimed invention naturally flow from the prior art disclosure, including regarding the surface, CIE1976 luminosity L* that is measured using a D65 light source in a diffuse lighting mode by receiving light in a direction at 80 with respect to a normal line to the surface at a visual field angle of 100 visual field for a measurement time of one second being 60 or more. “[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” MPEP 2144.05(II)(A).
Regarding claim 3, Ugi in view of JP ‘880 discloses 0.001 mass% or more and 0.500 mass% or less Ti (0.05 to 0.3% Ti) (JP ‘880 [0024]).
Regarding claim 4, Ugi in view of JP ‘880 discloses the passive film inhibits red rust (JP ‘880 [0006]) such that it has excellent weather resistance (JP ‘880 [0007], [0048]). The limitation of in a range from the surface to 1.0 um after the ferritic stainless steel is held in an atmosphere of 300°C to 900°C for 100 hours or longer, when a Cr content is represented by [Cr], a Si content is represented by [Si] and an Al content is represented by [Al] by unit mass%, the following formula (2) being satisfied, [Cr] + [Si] + [Al] > 18.0 ... (2), has been considered and determined to recite a property of the claimed ferritic stainless steel. The prior art discloses a substantially similar composition (Ugi [0006]-[0013]; JP ‘880 [0019], [0022], [0024]) and substantially similar processing (Ugi [0015]-[0019]), such that the properties of the claimed invention naturally flow from the disclosure of the prior art, including in a range from the surface to 1.0 um after the ferritic stainless steel is held in an atmosphere of 300°C to 900°C for 100 hours or longer, when a Cr content is represented by [Cr], a Si content is represented by [Si] and an Al content is represented by [Al] by unit mass%, the following formula (2) being satisfied, [Cr] + [Si] + [Al] > 18.0 ... (2).
Regarding claim 7, Ugi in view of JP ‘880 discloses the passive film inhibits red rust (JP ‘880 [0006]) such that it has excellent weather resistance (JP ‘880 [0007], [0048]). The limitation of in a range from the surface to 1.0 um after the ferritic stainless steel is held in an atmosphere of 300°C to 900°C for 100 hours or longer, when a Cr content is represented by [Cr], a Si content is represented by [Si] and an Al content is represented by [Al] by unit mass%, the following formula (2) being satisfied, [Cr] + [Si] + [Al] > 18.0 ... (2), has been considered and determined to recite a property of the claimed ferritic stainless steel. The prior art discloses a substantially similar composition (Ugi [0006]-[0013]; JP ‘880 [0019], [0022], [0024]) and substantially similar processing (Ugi [0015]-[0019]; JP ‘880 [0031]-[0033]), such that the properties of the claimed invention naturally flow from the disclosure of the prior art, including in a range from the surface to 1.0 um after the ferritic stainless steel is held in an atmosphere of 300°C to 900°C for 100 hours or longer, when a Cr content is represented by [Cr], a Si content is represented by [Si] and an Al content is represented by [Al] by unit mass%, the following formula (2) being satisfied, [Cr] + [Si] + [Al] > 18.0 ... (2).
Regarding claim 8, Ugi in view of JP ‘880 discloses the passive film inhibits red rust (JP ‘880 [0006]) such that it has excellent weather resistance (JP ‘880 [0007], [0048]). The limitation of in a range from the surface to 1.0 um after the ferritic stainless steel is held in an atmosphere of 300°C to 900°C for 100 hours or longer, when a Cr content is represented by [Cr], a Si content is represented by [Si] and an Al content is represented by [Al] by unit mass%, the following formula (2) being satisfied, [Cr] + [Si] + [Al] > 18.0 ... (2), has been considered and determined to recite a property of the claimed ferritic stainless steel. The prior art discloses a substantially similar composition (Ugi [0006]-[0013]; JP ‘880 [0019], [0022], [0024]) and substantially similar processing (Ugi [0015]-[0019]), such that the properties of the claimed invention naturally flow from the disclosure of the prior art, including in a range from the surface to 1.0 um after the ferritic stainless steel is held in an atmosphere of 300°C to 900°C for 100 hours or longer, when a Cr content is represented by [Cr], a Si content is represented by [Si] and an Al content is represented by [Al] by unit mass%, the following formula (2) being satisfied, [Cr] + [Si] + [Al] > 18.0 ... (2).
Related Art
Hamada (JP 2012-112025 machine translation)
Hamada discloses a ferritic stainless steel ([0001], [0020]) with an overlapping composition ([0025], [0032]-[0045]), substantially similar processing ([0048], [0056]-[0062]), and concentration of Al in the surface passivation film ([0024]).
Element
Claim 1
Hamada Disclosure
Hamada Citation
Si
0.05 to 2.50
0.5 or less
[0034]
Mn
0.05 to 1.50
0.5 or less
[0035]
C
0.025 or less
0.0101 or less
[0032]
P
0.040 or less
-
-
S
0.003 or less
-
-
N
0.025 or less
0.020 or less
[0033]
Ni
0.01 to 0.50
3 or less
[0042]
Cr
10.50 to 25.00
10.0 to 20.0
[0036]
Cu
0.01 to 1.80
1.5 or less
[0041]
Al
0.002 to 0.200
0.03 to 0.5
[0039]
Nb
0.001 to 1.00
0.05 or less
[0040]
Fe
Remainder
Remainder
[0025]
Ti
0.05 to 0.30
[0037]
Mo
1.5 or less
[0038]
V
1 or less
[0043]
Sn
0.5 or less
[0044]
B
0.0020 or less
[0045]
Applicant’s Disclosed Process
[0068]-[0080]
Hamada’s Disclosed Process [0048], [0056]-[0062]
Pretreatment
1100-1300°C
Casting
Casting
Hot Rolling
Hot Rolling
Annealing, optional
-
First Pickling
HCl or HNO3+HF
Pickling
Cold Rolling
Cold Rolling
Final Annealing
900-1100°C
30-90 seconds
Annealing
850-950°C
-
Nitric Acid Electrolysis
100-150 g/L concentration
50-70°C
100-150 mA/cm2 current density
60-120 seconds
Pickling in Nitric Acid
50 to 200 g/L
50-80°C
-
4-100 seconds
Final Pickling
HNO3+HF
-
JP ‘595 (JP H01-234595 machine translation)
JP ‘595 discloses a ferritic stainless steel (p. 1) with a similar composition (Table 1) manufactured by bright annealing to increase Si oxide then nitric acid electrolysis to selectively dissolve manganese oxide (p. 2).
Contact Information
Any inquiry concerning this communication or earlier communications from the examiner should be directed to STEPHANI HILL whose telephone number is (571)272-2523. The examiner can normally be reached Monday-Friday 7am-12pm.
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/STEPHANI HILL/Examiner, Art Unit 1735