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 .
Response to Amendment
Applicant’s amendment has been entered. Claims 1, 3-7, 10-11, 13, and 15 are pending. Claims 2, 8-9, 12, and 14 are canceled. Claiming “the hydrogen gas, the hydrocarbon gas, or the mixture of these gases is blown at a flow rate of 0.1 to 0.3 Nm3/min per ton of molten iron, and a nitrogen concentration [NIf in treated molten iron after being subjected to the decarburization and denitrification treatment is 30 mass ppm or lower” has overcome the rejection(s) under 35 USC 102(a)(1).
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 11 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 11 claims “The method for refining molten iron according to claim 8…”. Applicant has canceled claim 8 by the amendment filed May 29, 2026. As claim 8 is canceled, what is or is not encompassed by claim 11, which depends on claim 8, cannot be determined.
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.
Claim(s) 1, 3-5, 7, 10-11, and 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Sumitomo Metal (JPH04224612A). Sumitomo Metal is cited in the IDS filed November 8, 2023. References to Sumitomo Metal are directed to the examiner-supplied English language translation, which accompanied the office action mailed March 17, 2026.
Regarding claim 1, Sumitomo Metal discloses a method for refining molten iron (claim 1, [0001], [0006-07], [0026-27]). Sumitomo Metal discloses placing untreated molten iron with a carbon concentration of 1.7 mass% (Table 4) into a vessel (melted in electric furnace and poured into converter) (example 4 [0026]). Sumitomo Metal discloses blowing oxygen onto the untreated molten iron (top-blown oxygen) [0027]. Sumitomo Metal does not disclose pressurizing the vessel or that the refining treatment occurs under vacuum, and Sumitomo Metal discloses that the refining occurs in a “top-and-bottom dual-flow converter” [0018], and within the examples Sumitomo Metal discloses maintaining gas flow [0026-27] thereby disclosing that the treatment apparatus does not accumulate pressure. An apparatus which is not pressured and blows oxygen without accumulating pressure or inducing a vacuum is a process which blows oxygen under atmospheric pressure.
Sumitomo Metal discloses blowing a hydrogen gas (H2) to perform a decarburization treatment of the molten iron [0010], [0019-27]. Sumitomo Metal discloses that the hydrogen gas is blown at a flow rate of
≥
0.3 Nm3/min per ton of molten iron (overview section, [0010]) and discloses a narrower range of 0.3 to 2.0 m3 per ton of molten iron [0019]. As Sumitomo Metal discloses gas flows at values of Nm3/min (overview, [0010-11], [0019-27]), it would have been obvious that the 0.3-2.0 m3/min per ton disclosed by Sumitomo Metal [0019] is a normal m3/min flowrate. Both
≥
0.3
Nm3/min per ton iron and 0.3-2.0 m3/min per ton disclosed by Sumitomo Metal (overview, [0010], [0019]), meet the claimed range of 0.1 to 0.3 Nm3/min per ton of molten iron at a value of 0.3 Nm3/min per ton molten iron. When claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists, and a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. See MPEP 2144.05(I).
Sumitomo Metal is silent as to whether the treatment results in denitrification. Sumitomo Metal does not disclose adding nitrogen to the steel of examples [0021-27]. The discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition [or method] patentably new to the discoverer, thus the claiming of a new use, new function or unknown property which is inherently present in the prior art does not necessarily make the claim patentable (MPEP 2112(I)). If a prior art device, in its normal and usual operation, would necessarily perform the method claimed, then the method claimed will be considered to be anticipated by the prior art device (MPEP 2112.02(I)). When the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. See MPEP.2112.01(I). The difference in nitrogen concentration of inventive examples in the present disclosure between the product treated and the composition discharged from the treatment may be as low as 1 ppm (Inventive Examples No. 18, 19, 21, 22, 23, 24, 25, 26, 27, 30 in Table 2; Inventive Examples No. 35, 36, 37, 38, 39, 41 in Table 3). Every example in the present disclosure which treats with hydrogen (H2) as the bottom-blown gas results in at least 1 ppm of denitrification (Tables 1-3). Considering Sumitomo Metal manipulates steps of treating molten iron with hydrogen gas in overlapping flowrates [0001], [0006-07], [0010], [0019-27], with feed iron composition, and blown gases which meet those recited in claim 1 [0026-27], and considering every example in the present disclosure which blows hydrogen gas results in at least some amount of denitrification (Tables 1-3), Sumitomo Metal establishes a sound basis for believing that the method disclosed by Sumitomo Metal applied above, would result in at least some degree of denitrification.
Sumitomo Metal does not disclose that treated examples comprises nitrogen either before or after treatment ([0021-27], Tables 1-4). Sumitomo Metal discloses compositions of components as low as 5 ppm [0020]. The nitrogen concentration in treated iron is a material property that is inseparable from the chemical composition and processing conditions of the molten material. See MPEP2112.01(II). When the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. See MPEP.2112.01(I). The discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition patentably new to the discoverer. See MPEP2112(I). Considering Sumitomo Metal manipulates steps of treating molten iron with hydrogen gas in overlapping flowrates [0001], [0006-07], [0010], [0019-27], with feed iron composition, and blown gases which meet those recited in claim 1 [0026-27]; considering Sumitomo Metal does not add nitrogen in examples [0021-27], and considering every inventive example of the present disclosure which treats with hydrogen as the bottom-blown gas meets the nitrogen content limitation of present claim 1 (Tables 1-3), Sumitomo Metal establishes a sound basis for believing that a nitrogen concentration in iron treated by the process disclosed by Sumitomo Metal applied above, after being subjected to the decarburization and denitrification treatment is 30 mass ppm or lower. Further, in view of the above, it would have been obvious to one of ordinary skill in the art, at the time of filing, that the treated molten iron resulting from the method disclosed Sumitomo Metal applied above, after being subjected to the treatment [0001], [0006-07], [0019-27], would have a very low nitrogen concentration [N]f, particularly in view of the amounts which Sumitomo Metal does disclose in the iron ([0021-27], Tables 1-4), and a very low nitrogen concentration would meet or approach an amount of nitrogen of 30 mass ppm or lower.
Regarding claim 3, Sumitomo Metal discloses performing a vacuum degassing treatment in order to remove excess hydrogen following treatment with hydrogen gas [0020].
Regarding claim 4, Sumitomo Metal discloses that the untreated molten iron includes molten iron obtained by melting a cold iron source [0026].
Regarding claims 5 and 13, Sumitomo Metal discloses that treating Mn steels comprises forming the molten iron by melting a, cold iron source in a melting furnace [0017], [0026-27]. Sumitomo Metal also discloses that treating Mn steel may comprise untreated molten iron which is a mixture of molten pig iron into which an Fe-Mn iron source is charged [0017]. It would have been obvious for one of ordinary skill in the art, at the time of filing, to provide the untreated molten iron in the process disclosed by Sumitomo Metal [0017], [0020], [0026-27] as a mixture obtained by melting a cold iron source in a melting furnace and molten pig iron because Sumitomo Metal discloses a mixture of pig iron and an Fe-Mn iron source as molten iron suitable for the decarburization treatment [0017], and Sumitomo Metal discloses that the composition of example 4, which is an Fe-Mn alloy may be provided by melting a cold iron source in a melting furnace [0026]. Providing such a mixture would predictably yield a molten iron material suitable for decarburization treatment, as taught by Sumitomo Metal [0017]. A mixture obtained by melting a cold iron source in a melting furnace and molten pig iron is a mixture of primary molten iron. Example 1 of Sumitomo Metal directly treats pig iron [0021]. Sumitomo Metal discloses that the exemplified pig iron has a carbon concentration of 4.0 mass% (Table 1). In forming the mixture from pig iron as taught by Sumitomo Metal [0017], it would have been obvious to one of ordinary skill in the art that the pig iron would have the concentration of pig iron taught by Sumitomo Metal; therefore, it would have been obvious to one of ordinary skill in the art to provide pig iron having a carbon concentration of 4.0 mass %, as taught by Sumitomo Metal ([0021], Table 1).
Regarding claim 7, Sumitomo Metal discloses that the vessel is a converter [0026-27].
Regarding claims 10 and 11, Sumitomo Metal discloses that the untreated molten iron includes molten iron obtained by melting a cold iron source [0026].
Claim(s) 6 and 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Sumitomo Metal (JPH04224612A) as applied to claims 1, 4, and 5 above, and further in view of Millman (GB2553342A). Millman is cited in prior office action(s).
Regarding claim 6 and claim 15, Sumitomo Metal discloses adding a reducing agent to the molten iron after the decarburization treatment [0027], thereby disclosing that the provided iron can be reduced. Sumitomo Metal further discloses that the iron source may be a mixture of pig iron and an Fe-Mn source [0017]. Sumitomo Metal does not disclose that the cold iron source, which is melted, is reduced iron.
Millman teaches a method for refining molten iron (page 2 lines 9-15). Millman teaches blowing a hydrogen gas, to perform a denitrification treatment of the untreated molten iron (page 2 lines 12-15, 20-23; page 8 lines 26-31). Millman teaches that oxygen and hydrocarbons may be blown into the vessel (page 6 line 31 to page 7 line 10). Millman teaches that the source of the molten metal which can be treated can be one or more materials selected from: steel scrap; directly reduced iron; hot briquetted iron; pig iron: and hot blast furnace iron (page 2 lines 16-19, page 3 line 30 to page 4 line 1), thereby teaching a feed comprising a single iron source or a combination of iron sources for treatment.
Both Millman and Sumitomo Metal teach similar process for treating molten iron comprising a step of introducing hydrogen gas.
It would have been obvious for one of ordinary skill in the art at the time of filing, to provide reduced iron as the cold iron source in the process disclosed by Sumitomo Metal, applied above because Millman teaches that reduced iron either as an individual iron source or as a combination with pig iron is appropriate for molten iron treatments comprising introducing hydrogen gas (page 2 lines 12-23). As Millman teaches that reduced iron is an effective iron source for such a process (page 2 lines 12-23) the process of Sumitomo Metal, as applied to claim 4 or 5 above, wherein the cold iron source includes reduced iron will predictably result in providing a feed material from which nitrogen may be removed, as taught by Millman (page 2 lines 12-23).
Response to Arguments
Applicant's arguments have been fully considered but they are not persuasive.
Applicant’s argument that Sumitomo Metal (JPH04224612A) does not disclose the hydrogen gas, the hydrocarbon gas, or the mixture of these gases is blown at a flow rate of 0.1 to 0.3 Nm3/min per ton of molten iron, and applicant’s later, related argument that Sumitomo Metal lacks a suggestion of a technical concept regarding the appropriate amount of hydrogen gas, hydrocarbon gas or a mixture thereof, are not persuasive because Sumitomo Metal discloses that the hydrogen gas is blown at a flow rate of
≥
0.3 Nm3/min per ton of molten iron (overview section, [0010]), and Sumitomo Metal discloses a narrower range of 0.3 to 2.0 m3 per ton of molten iron [0019]. As Sumitomo Metal discloses gas flows at values of Nm3/min (overview, [0010], [0021-27]), it would have been obvious that the 0.3-2.0 m3/min per ton disclosed by Sumitomo Metal [0019] is a normal m3/min flowrate. A hydrogen flowrate of 0.3-2.0 Nm3/min per ton of molten iron meets the claimed range at 0.3 Nm3/min per ton. MPEP 2144.05 presents several examples wherein overlapping and/or approaching ranges are support a prima facie case of obviousness. Neither applicant, nor the disclosure as filed provides sufficient evidence, as explained in MPEP 2144.05(III), to show why the claimed flowrate range is nonobvious over the prior art flowrate range which meets the claimed range at a range endpoint.
Applicant presents further related arguments that Sumitomo Metal does not disclose a nitrogen concentration [N]f in treated molten iron after being subjected to the decarburization and denitrification treatment is 30 mass ppm or lower; that Sumitomo Metal is silent as to whether the treatment results in denitrification, and that Sumitomo Metal teaches blowing a gas from a bottom blowing nozzle into a molten iron, including a nitrogen gas. These arguments are not persuasive because the nitrogen gas disclosed by Sumitomo Metal in paragraphs [00010], [00011], [00019] and [00020] are disclosed as optional, alternative to other gasses, and small amounts when added as indicated by the wording of the Sumitomo Metal disclosure: “Further, the gas blown from the furnace bottom tuyere is hydrogen, but not only pure hydrogen but also [emphasis added] hydrogen mixed with a small amount of Ar, N2, CO, CO2 or hydrocarbons may be used” [0010]; “The blowing gas is basically H2, but as described above, a small amount of Ar, N2, CO, CO2 or [emphasis added] hydrocarbons may be mixed therewith” [0019], and “when the molten metal is rinsed by switching the bottom-blown gas from the H2 to the Ar, N2, CO2, CO or the like” [0020]. The nitrogen mentioned in Sumitomo [0011] is conventional stirring gas, not the decarburizing agent as indicated by “In a state where [C] in the molten iron is higher than 0.5%, T. Fe (the amount of iron oxides) in the slag is about 5%, which is not so high, even with a conventional stirring gas (Ar, N2 , CO2, CO or the like) of about 0.2Nm3/min” [0011]. The Sumitomo Metal disclosure is sufficient to encompass pure hydrogen [0010], and when nitrogen is present with the hydrogen, Sumitomo Metal presents N2 as an alternative to other gasses [0019], [0020]. Meanwhile, none of the examples disclosed by Sumitomo Metal add nitrogen ([0021-27], Tables 1-4). Within the present disclosure, every example which blows hydrogen gas results in at least some degree of denitrification (Tables 1-3), and every example with hydrogen as the as the bottom-blow gas during decarburization yields a nitrogen content [N]f less than 30 ppm. Sumitomo Metal’s disclosure of performing steps which the present disclosure shows yields an amount of nitrogen [N]f less than 30 ppm every, single time is more than sufficient to establish a sound basis for believing that the process disclosed by Sumitomo Metal would yield an amount of nitrogen [N]f less than 30 ppm. Sumitomo Metal’s silence on whether or not the process results in denitrification is not persuasive because the discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition [or method] patentably new to the discoverer, thus the claiming of a new use, new function or unknown property which is inherently present in the prior art does not necessarily make the claim patentable (MPEP 2112(I)); recognition of latent properties in the prior art does not render nonobvious an otherwise known invention (MPEP 2145 (II)), and the fact that the inventor has recognized another advantage (denitrification) which would flow naturally from following the suggestion of the prior art (the decarburization with hydrogen gas disclosed by Sumitomo Metal applied above) cannot be the basis for patentability when the differences would otherwise be obvious. See MPEP 2145(II).
Arguments that Millman (GB 2553342) does not cure what applicant perceives as deficiencies of Sumitomo Metal with respect to claim 1 are not persuasive because neither the present nor prior office action relies/relied on Millman to meet limitations recited in claim 1.
Applicant acknowledges all previously set forth grounds of rejections though appears to argue only limitations presented in claim 1 over the prior art.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 SEAN P O'KEEFE whose telephone number is (571)272-7647. The examiner can normally be reached MR 8:00-6:30.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sally Merkling can be reached at (571) 272-6297. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/SEAN P. O'KEEFE/ Examiner, Art Unit 1738
/SALLY A MERKLING/ SPE, Art Unit 1738
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