DETAILED ACTION
Response to Amendment
The Amendment filed 06/15/2026 has been entered. Claims 1-10 and 16-24 remain pending in the application. Claims 11-15 have been canceled. No new claims have been added.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-10 and 16-24 are rejected under 35 U.S.C. 103 as being unpatentable over CN 101255529 A of Luo (as cited in prior Office action with reference to its machine translation) in view of WO 2018/073117 A1 of Aarnts (as cited in prior Office action using its equivalent US 2020/0087761 A1 as its English translation).
The 35 U.S.C. 103 rejection of claims 1-10 and 16-24 over CN 101255529 A of Luo previously set forth in Final Rejection mailed 08/22/2025 is maintained in view of WO 2018/073117 A1 of Aarnts (using its equivalent US20200087761A1 as its English translation). Aarnts was incorporated in the Non-Final Rejection mailed 03/23/2026 to address the amendment regarding the Cr and Ni composition.
Luo teaches a high plastic strain ratio galvanized steel sheet with overlapping chemical composition, yield strength, tensile strength, plastic strain ratio, work hardening index, and elongation, as described in the 35 U.S.C. 103 rejection previously set forth in Final Rejection mailed 08/22/2025.
Luo teaches the high plastic strain ratio galvanized steel sheet has a balance of iron and unavoidable impurities ([0010]) and that the steel of the present invention is an ultra-low carbon steel ([0046]).
However, Luo does not explicitly teach Cr: 0.014-0.04, Ni: 0.018-0.04 of amended claim 1 and does not explicitly teach what the unavoidable impurities are.
Regarding the Cr and Ni content of claim 1, it would have been necessary and obvious to look to the prior art for exemplary amounts of unavoidable impurities in coated ultra low carbon steels sheets. Aarnts teaches an ultra low carbon steel strip, sheet, or blank which is optionally metallic coated (Abstract). Aarnts is considered analogous art since Aarnts and Luo are similarly considered with ultra low carbon steels sheets with similar chemical compositions and both have coatings. Aarnts teaches chromium and nickel are impurities and that a maximum content of 0.04 wt % for each is preferred to avoid harm to the properties of the steel ([0041]). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to form the steel of Luo, and adjusting and varying the unavoidable impurities, including Cr and Ni contents, such as within the claimed ranges, as taught by Aarnts, in order to form a conventional coated ultra low carbon steel using known and tested amounts of Cr and Ni impurities predictably suitable for ultra low carbon steel applications.
Luo, as modified by Aarnts, therefore reads on the limitation Cr: 0.014-0.04, Ni: 0.018-0.04 of amended claim 1.
Luo, as modified by Aarnts therefore reads on all the limitations of claims 1-10 and 16-24.
Claims 1-10 and 16-24 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2018/073117 A1 of Aarnts (as cited in prior Office action using its equivalent US 2020/0087761 A1 as its English translation).
Additionally, or alternatively, regarding claims 1-10 and 16-24, Aarnts teaches an ultra low carbon steel strip, sheet, or blank which is optionally metallic coated (Abstract, reads on claimed interstitial free low carbon steel strip, sheet or blank).
List 1
Instant claims (weight%)
2A of Aarnts (weight%)
Aarnts (weight%)
C
0.001-0.0022
0.0012
Max 0.007
Mn
0.04-0.13
0.094
Max 1.2
Si
0.002-0.013
0.003
Max 0.5
Al
0.03-0.07
0.049
Max 0.1
Ti
0.05-0.09
0.05 (rounded to one significant figure)
if Ti≥0.005 and Nb≥0.005:
0.06≤4Ti+4Nb+2Mo≤0.60
otherwise
0.06≤Ti+2Nb+2Mo≤0.60
Nb
≤0.002
0
V
≤0.004
0.001
Examples: 0.001-0.003 (Table 1)
P
0.002-0.007
0.005
Max 0.15
S
0.002-0.009
0.008
0.003-0.045
N
0.001-0.004
0.0021
Max 0.01
Ti+Nb+V
≤0.1
0.048 (calculated)
0.09-0.903 (calculated)
Cr
0.014-0.04
0.02
Max 0.06
Ni
0.018-0.04
0.016
Max 0.08
Optional elements
B
≤0.0002
0
Max 0.0015
Ca
≤0.001
-
Max 0.01
Cu
≤0.04
0.014
Max 0.10
Mo
≤0.02
0.005
Ti+2Nb+2Mo=0.06 (rounded to one significant figure)
if Ti≥0.005 and Nb≥0.005:
0.06≤4Ti+4Nb+2Mo≤0.60
otherwise
0.06≤Ti+2Nb+2Mo≤0.60
Sn
≤0.01
0.002
Max 0.01
Co: Max 0.01
Fe and unavoidable impurities
Balance
Remainder
Remainder
Mn+Si+10×P
0.06-0.20
0.15
0-3.2
Regarding claim 1, Aarnts teaches a steel with a chemical composition lying within the claimed ranges (Example 2A of Table 1 which is an interstitial free (IF) steel) and a broader disclosure with steels overlapping with the chemical composition of the claimed steel ([0010], [0030]-[0046], claims 1-2), as shown in List 1. While Aarnts does not explicitly disclose Ti+Nb+V and Mn+Si+10×P values, one can perform the calculation which results in values overlapping with the claimed ranges as shown in List 1. 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); In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997). See MPEP § 2144.05 I.
Aarnts therefore reads on the limitation an interstitial free low carbon steel strip, sheet or blank, wherein the steel has in weight% a composition of the following elements: C: 0.0010 -0.0022 Mn: 0.04-0.13 Si: 0.002 -0.013 Al: 0.03 -0.07 Ti: 0.05 -0.09 Nb: max 0.002 V: max 0.004 P: 0.002 - 0.007 S: 0.003 - 0.009 N: 0.001 - 0.004 wherein Ti+Nb+V together max 0.10 and Cr: max0.014 -0.04 Ni: max 0.018 - 0.04, and optionally: B: max 0.0002 Ca: max 0.001 Cu: max 0.04 Mo: max 0.02 Sn : max 0.01 the remainder being Fe and unavoidable impurities of claim 1.
Regarding the coating of claim 1, Aarnts teaches the strip, sheet or blank is coated with a zinc based coating (claim 7).
Aarnts therefore reads on the limitation wherein the steel is coated with a zinc alloy coating of claim 1.
Aarnts teaches the steels are hot rolled, cold rolled, continuously annealed with a top temperature of 810±20°C, hot dip galvanized at 470±10°C, cooled, and the cold roll strip is preferably skin passed ([0070], [0058], [0066]).
However, Aarnts does not explicitly teach the steel having a yield strength in transverse direction between 110 and 170 MPa, a tensile strength in transverse direction between 250 and 330 MPa, an elongation A80 in transverse direction of at least 42%, an average plastic strain ratio r of at least 2.00, a Mn+Si+10 x P value of 0.06-0.20 wt.%, and a strain hardening exponent n90 in transverse direction of at least 0.22; and a plastic strain ratio in diagonal direction r45 of at least 1.8, wherein the values of A80, r and n90 are the mean values of at least three measurements performed on at least three different strips of one cast of claim 1, the steel having an elongation A80 in transverse direction of at least 44% of claim 2, the steel having a strain hardening exponent n90 in transverse direction of at least 0.23 of claim 3, the steel having an average plastic strain ratio r of at least 2.15 of claim 4, the steel having a plastic strain ratio in diagonal direction r45 of at least 1.9 of claim 5, wherein the average plastic strain ratio r times the strain hardening exponent n90 in transverse direction is at least 0.44 of claim 6, wherein the plastic strain ratio in diagonal direction r45 times the strain hardening exponent n90 in transverse direction is at least 0.40 of claim 7, wherein the plastic strain ratio in transverse direction r90 times the strain hardening exponent n90 in transverse direction is at least 0.50 of claim 8, wherein the plastic strain ratio in diagonal direction r45 times a strain hardening exponent in diagonal direction n45 is at least 0.35 of claim 9, wherein a yield strength Rp 0.2 in transverse direction is between 110 and 155 MPa of claim 10, the steel having an elongation A80 in transverse direction of at least 52% of claim 16, the steel having a strain hardening exponent n90 in transverse direction of at least 0.24 of claim 17, the steel having an average plastic strain ratio r of at least 2.40 of claim 18, the steel having a plastic strain ratio in diagonal direction r45 of at least 2.3 of claim 19, wherein the average plastic strain ratio r times the strain hardening exponent n90 in transverse direction is at least 0.56 of claim 20, wherein the plastic strain ratio in diagonal direction r45 times the strain hardening exponent n90 in transverse direction is at least 0.52 of claim 21, wherein the plastic strain ratio in transverse direction r90 times the strain hardening exponent n90 in transverse direction is at least 0.66 of claim 22, wherein the plastic strain ratio in diagonal direction r45 times a strain hardening exponent in diagonal direction n45 is at least 0.50 of claim 23, and wherein the plastic strain ratio in transverse direction r90 is not more than 3.05 of claim 24.
Since the steel of Aarnts has a chemical composition, Ti+Nb+V values, and Mn+Si+10×P values, and processing overlapping with the claimed invention, one of ordinary skill in the art would reasonably expect the steel of Aarnts to necessarily possess the claimed yield strength, tensile strength, elongation, plastic strain ratio, strain hardening exponent in the claimed directions and relationships.
Where 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. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP § 2112.01 I. “Products of identical chemical composition can not have mutually exclusive properties.” A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present. In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). See MPEP § 2112.01 II. Therefore, it is expected that the steel of the prior art possesses the properties as claimed in the instant claims since a) the claimed and prior art products are identical or substantially identical in composition (see compositional analysis above), b) the claimed and prior art products are identical or substantially identical in structure (both are strip, sheet, or blanks), and c) the claimed and prior art products are produced by identical or substantially identical processes (both comprise hot rolling, cold rolling, continuous annealing, galvanizing, and skin passing steps). Since the Office does not have a laboratory to test the reference alloy, it is applicant’s burden to show that the reference alloy does not possess the properties as claimed in the instant claims. See In re Best, 195 USPQ 430, 433 (CCPA 1977); In re Marosi, 218 USPQ 289, 292-293 (Fed. Cir. 1983); In re Fitzgerald et al., 205 USPQ 594 (CCPA 1980).
Since the steel of Aarnts has overlapping Ti, Mn, C, and Si contents and process steps, as described above, one of ordinary skill in the art would reasonably expect the steel of Aarnts to necessarily possess the claimed mechanical properties of claims 1-10 and 16-24.
Aarnts therefore reads on all the limitations of claims 1-10 and 16-24.
Response to Arguments
Applicant's arguments filed 06/15/2026 have been fully considered but they are not persuasive.
35 U.S.C. 103 rejection over Luo in view of Aarnts
Regarding the P and S content, Applicant argues that Luo does not teach claimed P and S ranges and that Luo is teaching away from a low P content such as 0.002-0.007 wt% (remarks, page 1). Applicant argues that when Luo discusses the difficulty of control, that is a teaching of undesirability and is a teaching away (remarks, page 2).
In response, examples and preferred embodiments are not evidence of teaching away when acceptable broader ranges are taught by the prior art. See MPEP 2123(II). In other words, Luo's invention is not limited in scope to the S and P contents above 0.008% and 0.010% respectively, as argued by Applicant. Luo teaches P≤0.016% and S≤0.015% contents ([0010]), which includes values from zero to the maximum values of 0.016 of P and 0.015 respectively. Luo teaches S and P content target values of a foreign steel company are required to be controlled at S≤ 0.008% and P≤ 0.010% respectively, making it difficult to control the chemical composition during smelting ([0006], emphasis added) and that the object of the invention is to provide a method with looser restrictions on P and S in steel ([0008], emphasis added). In other words, Luo describes that controlling S≤ 0.008% and P≤ 0.010% is difficult and therefore expands the range to include P≤0.016% and S≤0.015%. At no point does Luo indicate that S≤ 0.008% and P≤ 0.010% are detrimental to the steel properties or are undesirable to the steel’s composition in any way and does not constitute a teaching away, as argued by Applicant. Rather, Luo recognizes that achieving low S and P contents can prove difficult in specific factory settings and provides a broader range of S and P rather than Applicant’s interpretation of at least 0.010 wt% P and at least 0.008 wt% S.
Regarding the Ni and Cr range, Applicant argues that there is no teaching or suggestion to modify Luo to include the claimed Cr and Ni amounts (remarks, page 2).
In response, as discussed in the 35 U.S.C. 103 rejections in this Office action, Luo teaches unavoidable impurities and Aarnts teaches Cr and Ni as impurities which should be preferably controlled to maximum content of 0.04 wt % for each to avoid harm to the properties of the steel ([0041]). Therefore, while Luo does not explicitly measure Cr and Ni, the teaching of Luo of unavoidable impurities includes Cr and Ni, as taught by Aarnts. An impurity, by definition, is an unwanted substance and therefore the terms “impurities” and “unavoidable impurities” are synonyms.
Regarding examples and unexpected results, Applicant argues that neither Luo nor Aarnts have any examples that have each component in the claimed range (remarks, pages 2-3). Applicant argues that one of ordinary skill in the art starting from Luo and looking at Aarnts’ steel would not arrive at the claimed invention (remarks, page 3). Applicant argues that Applicant’s claimed Cr and Ni ranges yield unexpected results not recognized in the prior art (remarks, page 3).
In response, regarding examples, examples and preferred embodiments are not evidence of teaching away when acceptable broader ranges are taught by the prior art. See MPEP 2123(II). In other words, comparative example 2A of Aarnts does not constitute a teaching away of the broader ranges taught by Aarnts which overlap with the claimed ranges as described in the 35 U.S.C. 103 rejections in this Office action and summarized in List 1 of this Office action. Furthermore, Aarnts teaches many other examples, including inventive examples, with compositions lying within the claimed ranges or which are close to the claimed ranges. For example, inventive example 11 of Table 1 taught by Aarnts lies within the claimed range of all elements except Ti and P (0.016 wt% Ti and 0.009 wt% P). However, inventive example 10 has 0.067 wt% Ti, which is within the claimed range of Ti, and inventive example 4A has 0.006 wt% P, which is within the claimed range of P. Aarnts further teaches adding P to a maximum 0.15 wt% to strengthen without forming undesired precipitates ([0033]) and adding Ti as a strong grain refiner ([0037]). As admitted by Applicant, prior art must be considered in its entirety as stated in MPEP 2141.02(VI). MPEP 2141.02(VI) also states "the prior art’s mere disclosure of more than one alternative does not constitute a teaching away from any of these alternatives because such disclosure does not criticize, discredit, or otherwise discourage the solution claimed…." In re Fulton, 391 F.3d 1195, 1201, 73 USPQ2d 1141, 1146 (Fed. Cir. 2004) (emphasis added). In this case, one of ordinary skill in the art would reasonably modify the steel composition of Luo with the broader disclosure and examples of Aarnts and arrive at the claimed invention, for example, by modifying the composition of Luo’s steel with inventive example 11 of Aarnts, the Ti composition of inventive example 10 and the P composition of inventive example 4A of Aarnts, to strengthen, refine grains, and avoid undesirable precipitates, as taught by Aarnts.
Regarding unexpected results, Applicant states that the claimed invention presents unexpected results but does not provide any evidence and/or data showing that the claimed steel performs in an unexpected manner. A showing of unexpected results must be based on evidence, not argument or speculation. In re Mayne, 104 F.3d 1339, 1343-44, 41 USPQ2d 1451, 1455-56 (Fed. Cir. 1997) (conclusory statements that claimed compound possesses unusually low immune response or unexpected biological activity that is unsupported by comparative data held insufficient to overcome prima facie case of obviousness). Applicant does not provide any comparison data that would support the assertion of unexpected results being present in the claimed invention. A mere conclusion that Applicant’s steel exhibits unexpected results is not enough to show nonobviousness. Evidence of unexpected properties may be in the form of a direct or indirect comparison of the claimed invention with the closest prior art which is commensurate in scope with the claims. See In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). See MPEP 716.02.
In summary, Luo in view of Aarnts, or alternatively Aarnts, teaches a steel with overlapping chemical composition and processing as described in the 35 U.S.C. 103 rejections in this Office action. Absent any clear and convincing evidence and/or arguments to the contrary, one of ordinary skill in the art would expect the steel of Luo in view of Aarnts, or alternatively the steel of Aarnts, to possess the claimed properties. A prima facie case of obviousness has been properly established herein. As the Patent Office does not possess the laboratory facilities to test any differences in the claimed invention versus that of the reference, the burden shifts to applicant to demonstrate otherwise.
35 U.S.C. 103 rejection over Aarnts
Applicant argues that Alloy 2A is not according to Aarnts’ invention, is an alloy to be avoided and a teaching away (remarks, pages 3-4). Applicant argues that Aarnts does not have any example that has each component in the claimed range and that there are unexpected results in the claimed invention (remarks, page 4).
In response, examples and preferred embodiments are not evidence of teaching away when acceptable broader ranges are taught by the prior art. See MPEP 2123(II). See Response to Arguments above regarding examples and unexpected results for the 35 U.S.C. 103 rejection over Luo in view of Aarnts. In this case, one of ordinary skill in the art would reasonably modify the steel composition of the broader disclosure of Aarnts with the examples of Aarnts and arrive at the claimed invention, for example, by modifying the composition of inventive example 11 of Aarnts with the Ti composition of inventive example 10 and the P composition of inventive example 4A of Aarnts, to strengthen, refine grains, and avoid undesirable precipitates, as taught by Aarnts.
In summary, Aarnts teaches a steel with overlapping chemical composition and processing as described in the 35 U.S.C. 103 rejections in this Office action. Absent any clear and convincing evidence and/or arguments to the contrary, one of ordinary skill in the art would expect the steel of Aarnts to possess the claimed properties. A prima facie case of obviousness has been properly established herein. As the Patent Office does not possess the laboratory facilities to test any differences in the claimed invention versus that of the reference, the burden shifts to applicant to demonstrate otherwise.
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 extension fee 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.
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/M.A./Examiner, Art Unit 1733
/REBECCA JANSSEN/Primary Examiner, Art Unit 1733
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