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 .
Election/Restrictions
Applicant’s election without traverse of group I claims 1-9 in the reply filed on 2/20/2026 is acknowledged.
Claims 10-34 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), there being no allowable generic or linking claim. Election was made without traverse.
Claim Rejections - 35 U.S.C. § 112
The following is a quotation of 35 U.S.C. § 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claim 9 is rejected under 35 U.S.C. § 112(d) as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends.
9. This claim expands rather than further limits claim 8.
Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
Claim Rejections - 35 U.S.C. § 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 of this title, 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 1-9 are rejected under 35 U.S.C. § 103 as being unpatentable over Nakasuji et al., U.S. Patent No. 5,501,834 [hereinafter Nakasuji] in view of Sawamura et al., U.S. Patent App. Pub. No. 2019/0226066 A1 [hereinafter Sawamura], Filonov et al., RU 2625514 C1, and as evidenced by Yu et al., A sequential dual-passivation strategy for designing stainless steel used above water oxidation, 70 Materials Today (2023) [hereinafter Yu]. A machine translation was used for Filonov et al. [hereinafter Filonov].
The body of the claim is generally written with parentheses following the limitations indicating the prior art’s teachings and/or examiner notes.
1. The prior art does not explicitly teach a bilayer passive film structure of a substrate, comprising an inner layer comprising an oxide of a first element, and an outer layer comprising an oxide of a second element, wherein the passivation potential of the first element is lower than the passivation potential of the second element, and the passivation potential of the second element is lower than the transpassivation potential of the first element.
The Applicant’s specification teaches a method to form the bilayer passive film comprising
forming a stainless steel which comprises in percentage by weight, 15% < Cr < 30%, 10% < Mn < 30%, and 0.5% < Si < 4%, and a remainder of Fe and inevitable impurities, and
resting the formed stainless steel block in vacuum thermal treatment, kept at 1150 to 1250°C for 2 to 4 hours so that the alloying elements undergo a full solid solution. App. Spec. [0064], [0081]; see also Yu abstract, p. 9 (teaching the Applicant’s Mn-containing stainless steel subjected to homogenization heat treatment then forms the bilayer passive film when).
I. Nakasuji
Nakasuji teaches an austenitic stainless steel. Nakasuji abstract, col. 2 ll. 53-56, col. 3 ll. 23-30. Nakasuji teaches the steel comprising 17 wt% Cr, 10-30 wt% Mn, balance Fe. Nakasuji abstract, table 1, Nos. 1-8 & 10-11. Nakasuji teaches the stainless steel comprises Si as a deoxidizing agent and should be not more than 2.0%. Nakasuji abstract, col. 4 ll. 11-14. Nakasuji teaches that heat treatment may be applied, which can be at 1200°C. Nakasuji col. 4 l. 60 – col. 5 l. 2, col. 5 ll. 10-15, col. 7 ll. 41-43.
II. Silicon 0.5-4%: Sawamura
Sawamura teaches steel comprising silicon being between 1.01-1.97 mass% silicon. Sawamura [0055], [0066]. Like Nakasuji, Sawamura teaches the silicon is a deoxidizing agent. Sawamura [0070].
Therefore, it would have been obvious with a reasonable expectation of success to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified the aforementioned prior art’s stainless steel to comprise 1.01-1.97 mass% silicon to yield the predictable result of having a suitable silicon content to be o deoxidizing agent.
III. Heat Treatment: Filonov
Filonov teaches heating stainless steel to 1150-1200°C for 2 hours to homogenize and then cool in water.
Therefore, it would have been obvious with a reasonable expectation of success to a person having ordinary skill in the art before the effective filing date of the claimed invention to have modified the aforementioned prior art’s stainless steel by heating it to 1150-1200°C for 2 hours to homogenize and then put in water to cool. Filonov abstract, p. 6.
Since the prior art teaches the method steps taught by the specification, the prior art will inherently form the claimed bilayer along with the rest of the claimed properties.
2. The bilayer passive film structure according to claim 1, wherein the passivation potential of the second element is not greater than 1000 mV (rejected for similar reasons stated in the claim 1 recection).
3. The bilayer passive film structure according to claim 2, wherein the passivation potential of the second element is 700 mV to 800 mV (rejected for similar reasons stated in the claim 1 recection).
4. The bilayer passive film structure according to claim 1, wherein the second element is Mn (rejected for similar reasons stated in the claim 1 rejection).
5. The bilayer passive film structure according to claim 1, wherein the first element is Cr (rejected for similar reasons stated in the claim 1 rejection).
6. The bilayer passive film structure according to claim 1, wherein the substrate comprises stainless steel (rejected for similar reasons stated in the claim 1 rejection).
7. The bilayer passive film structure according to claim 1, wherein the substrate comprises austenitic stainless steel (rejected for similar reasons stated in the claim 1 rejection).
8. The bilayer passive film structure according to claim 1, wherein the structure has no pitting at < 1000 mV in an acidic or neutral environment (rejected for similar reasons stated in the claim 1 rejection).
9. The bilayer passive film structure according to claim 8, wherein the structure has no pitting at < 1150 mV in an acidic or neutral environment (rejected for similar reasons stated in the claim 1 rejection).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Hosung Chung whose telephone number is (571) 270-7578. The examiner can normally be reached Monday-Wednesday, 9 AM - 6 PM CT.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, James Lin can be reached on (571) 272-8902. The fax phone number for the organization where this application or proceeding is assigned is (571) 273-8300.
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/HOSUNG CHUNG/Primary Examiner, Art Unit 1794