DETAILED ACTION
Examiner’s Note
This office action is in response to applicants’ amendments to the claims and remarks filed March 20, 2026. Claims 1-8 are pending with claims 7 and 8 remaining withdrawn as directed to non-elected subject matter.
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 1-6 are rejected under 35 U.S.C. 103 as being unpatentable over Ohgami et al. (PGPub US 2004/0050445).
Regarding applicants’ claim 1, Ohgami et al. disclose a steel pipe formed from a hot-rolled steel sheet (paragraph 0063). The steel composition comprises (in weight %): C: 0.01-0.20%, Si: 0.05-1.0%, Mn: 0.1-2.0%, Al: 0.001-0.05%, with a balance of iron and unavoidable impurities (paragraph 009). The microstructure may be ferrite and pearlite, and the average ferrite grain size is not smaller than 20µm (paragraph 0009). The hot-rolled steel sheet prior to undergoing formation into a pipe is a hot-rolled steel sheet, and satisfies the intended use of being “for a hyper-tube” because a hyper-tube can be manufactured from the hot-rolled steel sheet.
While Ohgami et al. do not appear to disclose the exact compositional ranges claimed, one of ordinary skill in the art before the effective filing date of applicants’ claimed invention to select from the proportions disclosed by Ohgami et al. including values which fall within applicants’ claimed ranges and which satisfy applicants claimed Relational Expressions.
With respect to the claimed relational expressions and grain size, the values disclosed by Ohgami et al. overlap those claimed by applicants, and therefore include values which satisfy the claimed requirements. For example, a composition including 0.15% carbon, 1% silicon, and 1.5% manganese with a grain size of 20µm would yield the following equalities for relational expressions 1-3: [Relational Expression 1] 350 ≤ 364, [Relational Expression 2] 100 ≤ 128, and [Relational Expression 3] 48 > 27.
Substantially identical materials are expected to have substantially identical properties. Ohgami et al. disclose a hot-rolled steel sheet having a composition and micro-structure overlapping that claimed by applicants. One of ordinary skill in the art before the effective filing date of applicants’ claimed invention would have found it obvious to form a hot rolled steel sheet substantially identical to that claimed by applicants by selecting compositional proportions within applicants’ claimed range and with a microstructure and grain size within applicants’ claimed values such that the resulting sheet sheets would be expected to have the substantially identical properties including yield strength.
Regarding applicants claim 2, Ohgami et al. disclose a ferrite content of 70 to 98% (paragraph 0015). If the remaining structure is pearlite, the pearlite fraction would be 2-30% and the area fractions of ferrite and pearlite would overlap applicants’ claimed ranges. While Ohgami et al. do not appear to disclose the exact ranges claimed by applicants, one of ordinary skill in the art before the effective filing date of applicants’ claimed invention to select from the proportions disclosed by Ohgami et al. including values which fall within applicants’ claimed ranges.
Regarding applicants’ claim 3, the steel of Ohgami et al. does not require the presence of titanium, niobium, or vanadium and if present would only be at levels of unavoidable impurities. The amounts of unavoidable impurities may include amounts down to 0 wt.% which overlaps the claimed requirement, or is at least so close to applicants’ claimed limits as to establish a prima facie case of obviousness (MPEP 2144.05 I).
Regarding applicants’ claim 4, the microstructure may be ferrite and pearlite, and the average ferrite grain size is not smaller than 20µm (paragraph 0009) which overlaps applicants’ claimed range. One of ordinary skill in the art before the effective filing date of applicants’ claimed invention would have found it obvious to from steel sheets having a grain size within the disclosed range of 20µm or more, including values within the claimed range.
Regarding applicants’ claim 5, substantially identical materials are expected to have substantially identical properties. Ohgami et al. disclose a hot-rolled steel sheet having a composition and micro-structure overlapping that claimed by applicants. One of ordinary skill in the art before the effective filing date of applicants’ claimed invention would have found it obvious to form a hot rolled steel sheet substantially identical to that claimed by applicants by selecting compositional proportions within applicants’ claimed range and with a microstructure and grain size within applicants’ claimed values such that the resulting sheet sheets would be expected to have the same properties including an impact energy, and vibration properties satisfying applicants’ claimed requirements.
Regarding applicants’ claim 6, Ohgami et al. do not appear to explicitly limit the thickness of the steel sheets but exemplify steel sheets at a thickness of 10mm (paragraph 0065, 0069, and 0075). One of ordinary skill in the art before the effective filing date of applicants’ claimed invention would have found it obvious to form the steel sheet at a thickness of 10mm, where 10mm has been exemplified as a suitable thickness for the steel sheets of Ohgami et al.
Response to Arguments
Applicants’ arguments filed March 20, 2026 have been considered but have not been found to be persuasive.
Applicants argue that the claimed relational expressions are critical in securing desirable properties including yield strength, opposed to mere arbitrary selections and in contrast Ohgami who does not recognize such relationships. However the disclosure of Ohgami is not limited to the cited examples, and while overlapping, the selection is more than merely arbitrary.
Applicants may establish non-obviousness by demonstrating critically of a range such as by demonstrating unexpected results, however the difference between the yield strength of the examples and that claimed by applicants is not unexpected. Symbols A-1 and D-1 of Ohgami include silicon in an amount less than that claimed by applicants, where Symbols B-1 through G-1 have carbon amounts less than the proportions disclosed by applicants. Ohgami discloses that carbon is an element that enhances strength of a steel (paragraph 0033) and discloses that silicon enhances strength of a steel (paragraph 0034). Because elements that are disclosed as providing strength are lower in the cited examples it is not unexpected that they exhibit a lower strength. It would be within ordinary skill to select from the proportions of carbon and silicon disclosed by Ohgami, not as mere arbitrary selections, but in consideration of the known effects these elements have on the properties of the steel.
Given that the compositional proportions disclosed by Ohgami overlap applicants’ claimed ranges, and that the effect of the overlapping elements is known, the claimed ranges and relational expressions are not found patentably distinct, and the rejections over Ohgami are maintained.
Conclusion
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 ADAM C KRUPICKA whose telephone number is (571)270-7086. The examiner can normally be reached Monday-Friday 8-5pm EST.
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/Adam Krupicka/Primary Examiner, Art Unit 1784
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