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 Acknowledgment is made of applicant’s claim for foreign priority under 35 U.S.C. 119 (a)-(d). Information Disclosure Statement The information disclosure statement (IDS) submitted on 12/06/2023 is being considered by the examiner. Claim Rejections - 35 USC § 112 (b) 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. Claims 1-1 5 are 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 1 recites the limitation " a circulation time of the molten steel is ≥ 3 min” and “a circulation time of the molten steel is ≥ 2 min” renders the claim indefinite, as the claim does not recite any upper limit of the time, which make the time for indefinite or infinity. One of the embodiment of instant specification , line 20-24 describes the time as 3-10 min and 2-10 min, but this is a preferred embodiment and the claim language allows the circulation can go for indefinite period. Appropriate corrections are required. Claims 2-8 and 10-15 are also rejected for the same reason due to their dependency on claim 1. Claim 5 recite the limitation “ 70% to 80% of a hot metal ladle top slag is removed ” in line 3, renders the claim indefinite, because it is unclear what is the basis of measuring the percentage, and how this percentage has been measured or calculated , instant Specification does not provide any guideline about this limitation, for example whether it is the percentage of total amount of the slag, or percentage of volume or percentage of thickness, or percentage of molten iron surface as some prior art as shown in the rejection section Zhao Jiaqi, et.al. [ CN112921148A ] (machine translation) (Zhao hereafter) slag removal is performed to expose percentage of the molten iron surface ((see. step 1 and step 3 Zhao’s claim 1, and [0010]), and/or pertinent prior art section Yang Kehzhi, et.al. [ CN112342333A ] (machine translation, original provided in the IDS) teaches the percentage of the bright surface of the slag remov al ( see Yang’s claim 2). As the limitation is unclear, this limitation is not considered during the examination purpose. Claim 6 and 15 recite the limitation “a tapping amount reaches 1/6 to 1/4” in line 5, and then “the tapping amount reaches 4/5 or more” in line 6, both the limitations render the claim indefinite, because it is unclear what is the basis of measuring the fraction of the slag, and how this fraction has been measured or calculated, instant Specification does not provide any guideline about this limitation, for example whether it is the fraction of total amount of the slag, or fraction of volume or fraction of thickness, as some prior art as shown in the rejection section Hu Hantao, et.al. [CN109402321A] (machine translation, original provided in the IDS) (Hu’321A, hereafter) teaches that the slag thickness of a steel ladle is smaller than or equal to 50 mm in the steel tapping process, 2.0-5.0 kg of lime is added into per ton of steel in the early stage of steel tapping, 0.5-2 kg of an Al quality modification agent is added in per ton of steel at the last stage of steel tapping (see Hu’321A ’s abstract). As the limitation is unclear, this limitation is not considered during the examination purpose. Claim 14 recites a limitation “3/4 of a hot metal ladle top slag is removed ” in line 3, renders the claim indefinite, because it is unclear what is the basis of measuring this fraction, and how this fraction has been measured or calculated, instant Specification does not provide any guideline about this limitation, for example whether it is the fraction of total amount of the slag, or fraction of volume or fraction of thickness, or percentage of molten iron surface as some prior art as shown in the rejection section Zhao Jiaqi, et.al. [ CN112921148A ] (machine translation) (Zhao hereafter) slag removal is performed to expose more than 98% of the molten iron surface ((see. step 1 and step 3 Zhao’s claim 1, and [0010]), and/or pertinent prior art section Yang Kehzhi, et.al. [ CN112342333A ] (machine translation, original provided in the IDS) teaches the percentage of the bright surface of the slag remov al (claim 2). As the limitation is unclear, this limitation is not considered during the examination purpose. Also it is to be noted, the claim 14 depends from claim 5 and claim 5 recites the percentage of hot metal ladle top slag is removed , whereas claim 14 recites the fraction of a hot metal ladle top slag is removed , further renders the claim indefinite, as it is not clear whether the “ hot metal ladle top slag is removed ” in claim 14 recites different limitations than the claim 5. Appropriate corrections are required. Claims 2-1 5 are also rejected due to their dependency on claim 1. 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. Claims 1- 5, 7-11 and 13 are FILLIN "Pluralize claim, if necessary, and then insert the claim number(s) which is/are under rejection." \d "[ 1 ]" rejected under 35 U.S.C. 103 as being unpatentable over Hu H antao , et.al. [ WO2021036974A1 ] (machine translation) ( Hu hereafter) and in view of Lyu Zhiyong , et.al. [ CN108998613A ] (machine translation) ( Lyu hereafter) . Regarding claim 1, Hu discloses a method for preparing a titanium-containing ultra-low-carbon steel, comprising ( the production of titanium-containing ultra-low carbon steel, the process path adopted in this invention is as follows: [0048] ) hot metal pretreatment, primary converter refining, vacuum refining, continuous casting, hot rolling, pickling and cold rolling ( hot metal desulfurization and dephosphorization - converter decarburization - steel tapping, ladle top slag modification - vacuum decarburization, Ti deoxidation, Al addition and composition fine-tuning - addition of rare earth metals - continuous casting - hot rolling - pickling - cold rolling see Hu’s claim 7, [ 0048]) ; wherein in the vacuum refining, after decarburization is completed, then Al is added for deoxidization treatment, after which a circulation time of the molten steel is ≥ 3 min ( After RH vacuum decarburization is completed, then Al is added, and then the molten steel is circulated for ≥3 minutes , see Hu’s claim 1 ) ; then additional alloying and rare earth components are added to the molten steel, after which a circulation time of the molten steel is ≥ 2 min ( add other alloying elements and/or adjust the composition of molten steel according to the finished product specifications, and circulate the molten steel for ≥2 minutes , see Hu’s claim 1) , wherein an oxide of Re 2 O 3 · Al 2 O 3 is finally generated in the molten steel; and the vacuum refining is completed ( Rare earth metals Ce and/or La are added to the molten steel, and oxides Ce 2 O 3 · Al 2 O 3 and/or La 2 O 3 · Al 2 O 3 are finally generated in the molten steel, achieving smooth casting , see Hu’s claim 1 ). Hu further teaches i n the smelting of ultra-low carbon steel, the oxygen (free oxygen and combined oxygen that is added during converter smelting ) is the main oxygen source in the entire smelting process ([0003]), but Hu is silent about “ after decarburization is completed, a free oxygen content in molten steel is 100 to 350 ppm ”. However, Lyu teaches a control method for free oxygen in ultra - low-carbon steel , wherein the steel production technology includes hot metal pretreatment , converter smelting, RH furnace vacuum refining and continuous casting. Lyu ’s method ensures safety production of a continuous casting and a casting blank is free of defects in quality (Abstract) . Lyu then teaches in the vacuum refining, after decarburization is completed , a free oxygen content in molten steel is 310 ppm ( 0.031% ) , then Al is added for deoxidization treatment, after which a circulation time of the molten steel is 5 min ( after hot metal pretreatment [002 8 ] and converter smelting [002 9 ] , RH furnace vacuum refining and the RH vacuum circulation device has started, w hen the decarburization time reaches 20 minutes, the oxygen value of the molten steel is tested to be 0.031% and then aluminum wire rod for deoxidation is being added . After 5 minutes of net circulation, the RH vacuum circulation device is shut down , see Lyu ’s [0029]). Lyu teaches t he total oxygen in molten steel includes free oxygen dissolved in the steel and oxygen present in oxide inclusions. At the end of converter smelting, the oxides in the molten steel approach zero, and the total oxygen is mainly free oxygen. After the molten steel is completely cooled, the weight percentage of free oxygen in the molten steel is less than 0.001%, and the total oxygen is mainly oxygen from oxides [0004] and Lyu also teaches e xcessive free oxygen leads to poor safety during casting, while insufficient free oxygen causes excessive oxide inclusions in the steel, making it difficult to meet process control requirements ([0006]). Lyu’s process is directed to the produc tion of ultra - low-carbon steel and th erefore, analogous to the instant claim and Hu . Therefore, it would have been further obvious to one of ordinary skill in the art before the effective filling date of the present invention , to have Lyu ’s teachings of maintaining a free oxygen content in molten steel after the decarburization to modify Hu’s method to produce a defect free steel product with high quality. Regarding Claim 2, all the discussions above claim 1 are applicable for claim 2 in addition, H u discloses in the vacuum refining, before the decarburization treatment, the free oxygen content in the molten steel is adjusted to satisfy a mass ratio O/C=1.96 (a fter converter blowing, [%C] = 280ppm, [%O] = 550ppm; before vacuum treatment, and the vacuum decarburization started [0050] , therefore calculated O/C = 550/280 = 1.96 ) . Hu’s disclosed mass ratio O/C is within the as recited range of the instant claim. It is to be noted, claim recites “and/or” in between three different limitations, and use of “or” make these limitations as optional, and not required by the claim language . Therefore, with a teachings of mass ratio O/C, Hu already meet the entire claimed limitation. In addition, Hu also discloses the rare earth component comprises Ce or La, and is added in an amount based on a mass ratio REM/T.O= 0.8-2.6 , wherein REM represents a mass of the rare earth component added in kg, and T.O represents a total oxygen amount in the steel in ppm ( the rare earth metal is composed of Ce and /or La see Hu’s claim 2, 3, and [0013], [0014], Hu defines a ratio of rare earth addition mass (kg) to total oxygen in steel (ppm) REM/T.O see [0012] and [0030] and the value of REM/T.O = 0.8-2.6 see Hu’s claim 6 and [0017], and an example REM/T.O = 1.35 [0050]) . Hu’s mass ratio a mass ratio of REM/T.O is within the as recited range of the instant claim. Hu teaches t here are two possible adverse consequences: 1) t he generated single rare earth oxide has a high specific gravity and is not easy to float and 2) t he content of free Re , in the steel increases sharply, reacts with the refractory material, contaminates the molten steel, and in severe cases, can lead to the melting and loss of the stopper rod or nozzle, resulting in abnormal casting or interruption , therefore, the REM/T.O within the disclosed limit is required ([0030]). Therefore, it would have been further obvious to one of ordinary skill in the art before the effective filling date of the present invention , to have Hu’s teachings in view of Lyu to produce a defect free steel product with high quality without any refractory material contamin ants. Hu further teaches a content of impurities other than rare earth element(s) in the rare earth component is < 0.1 wt. %, wherein a total oxygen amount T.O is < 100 ppm, and a N content is ≤ 30 ppm, as Hu teaches a mass percentage of the rare earth metal composition is: Ce 60-70%, La 30-40% , (see Hu’s claim 3 and [0019]), therefore, Hu’s composition does not contain any oxygen and nitrogen, and it would have expected to have those about zero and therefore, meet the limitations. Regarding Claim 3, all the discussions above claim 1 and 2 are applicable for claim 3 , wherein H u already discloses the oxide of Re 2 O 3 · Al 2 O 3 is Ce 2 O 3 · Al 2 O 3 or La 2 O 3 · Al 2 O 3 ( Rare earth metals Ce and/or La are added to the molten steel, and t he molten steel is circulated for ≥2 min, and oxides Ce 2 O 3 · Al 2 O 3 and/or La 2 O 3 · Al 2 O 3 are finally generated in the molten steel, achieving smooth casting , see Hu’s claim 1, [0019]). Regarding Claim 4, all the discussions above claim 1 and 2 are applicable for claim 4 wherein Hu already discloses a vacuum refining device used for the vacuum refining is an RH furnace or a VD furnace or a VOD furnace ( RH vacuum decarburization see Hu’s claim 1) Hu further teaches a vacuum refining device is Ruhrstahl-Heraeus (RH) furnace (see Hu’ [0019] ). Lyu also teaches RH furnace vacuum refining: Vacuum circulation decarburization and deoxidation are carried out in the RH vacuum refining furnace (see Lyu’ [001 3 ] ). Regarding Claim 5, all the discussions above claim 1 are applicable for claim 5 in addition, Hu discloses the hot metal pretreatment, desulfurization is adopted (hot metal desulfurization , see H u’s claim 7 ) . But Hu is silent about the “KR desulfurization is adopted, after which 70% to 80% of a hot metal ladle top slag is removed; and/or a S content in the hot metal after the desulfurization is ≤ 20 ppm ” . Lyu teaches after the d esulfurization and the slag is removed , a S content in the hot metal after the desulfurization is ≤ 3 0 ppm ( ≤0.003% ) (w hen the weight percentage of sulfur in the hot metal is ≤0.003%, the hot metal is transferred to the converter for smelting , see Lyu’s claim 1, [0011]). Lyu’s disclosed S content in the hot metal after the desulfurization is overlapping with the as recited in the instant claims. Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filling date of the present invention , to have selected and produced S content in hot metal from the teachings of Lyu that falls within the instantly-claimed ranges, because “ 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)” [See MPEP § 2144.05.I]. Therefore, it would have been further obvious to one of ordinary skill in the art before the effective filling date of the present invention , to have Lyu ’s teachings to modify Hu’s method to control sulfur content for producing a defect free steel product with high quality. It is to be noted, claim recites “and/or” in between the two different limitations, and use of “or” make these limitations as optional, and not required by the claim language. Therefore, with a teachings of S content in the hot metal after the desulfurization , Lyu meet the entire claimed limitation. Regarding Claim 7 and 8 , all the discussions above claim 1 are applicable for claim 7 and 8 in addition, H u discloses the titanium-containing ultra-low-carbon steel comprises the following compo sition in mass percentage (Hu’s Claim 1) and the claimed composition has been shown in the following table for the comparison. Element Instant Claim 7 (mass %) Instant Claim 8 (mass %) Hu 's composition wt. % [ Hu’s Claim 1 ] Within/Overlapping Range C ≤ 0.005% ≤ 0.0018% ≤ 0.005% Within /overlapping Si ≤ 0.05% ≤ 0.03% ≤ 0.05% Within / overlapping Mn 0.05 to 0.3%, 0.07 to 0.15%, 0.05 to 0.3%, Within / overlapping Al 0.04 to 0.15% 0.04 to 0.0.07% 0.02 to 0.1% Overlapping / overlapping Ti 0.04 to 0.1 % 0.04 to 0.06 % 0.008 to 0.05 % Overlapping / overlapping P ≤ 0.05% ≤ 0.0 1 5% ≤ 0.05% Within / overlapping S ≤ 0.02% ≤ 0.0 05 % ≤ 0.02% Within / overlapping N N ≤ 0.003% N ≤ 0.003% N ≤ 0.003% Within / overlapping Relation to Al and Ti Al content is greater than a Ti content Al content is greater than a Ti content Al content ≥ Ti content Within / Within Fe and unavoidable impurities Balance Balance Balance Overlapping / overlapping Hu ’s composition for all elements is overlapping with the as recited in the both of the instant claim s . Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filling date of the present invention , to have selected and produced a composition from the teachings of Hu that falls within the instantly-claimed ranges, because “ 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)” [See MPEP § 2144.05.I]. Hu further teaches t he steel types applicable to th e invention are ultra-low carbon steel products, i.e., carbon content ≤ 0.005 wt. %, and Al content ≥ Ti content in the molten steel composition, so as to ensure that the final deoxidation of the molten steel before addition of rare earth is controlled , by Al in the molten steel (Hu’s [0027]) . Therefore, it would have been further obvious to one of ordinary skill in the art before the effective filling date of the present invention , to have Hu’s teachings in view of Lyu to produce a titanium containing ultra-low carbon steel products with defect free and high quality without any rare earth refractory material contamin ants. Regarding Claim 9, all the discussions above claim 1 are applicable for claim 9, wherein H u already discloses after Al is added for deoxidization treatment, the circulation time of the molten steel is ≥3 min ; ( After RH vacuum decarburization is completed, then Al is added, and then the molten steel is circulated for ≥3 minutes , see Hu’s claim 1) and in an example, the molten steel is circulated for 9 minutes after Al is added (see Hu’s [0050]). Therefore, Hu’s the circulation time of the molten steel after addition of Al is within the as recited in the instant claim. It is to be noted, claim recites “and/or” in between the two different limitations, and use of “or” make these limitations as optional, and not required by the claim language. Therefore, with a teachings of the circulation time of the molten steel after addition of Al, Hu already meets the entire claimed limitation. However, In addition, Hu already discloses the additional alloying and rare earth components are added to the molten steel, the circulation time of the molten steel is ≥ 2 min ( other alloying elements and/or adjust the composition of molten steel according to the finished product specifications, and circulate the molten steel for ≥2 minutes , see Hu’s claim 1) and in an example, the molten steel is circulated for 5 minutes after adding the rare earth elements (see Hu’s [0050]). Therefore, Hu’s the circulation time of the molten steel after adding the rare earth elements is within the as recited in the instant claim. Regarding Claim 10, all the discussions above claim 1 are applicable for claim 10 in addition, H u discloses during the continuous casting, a pass rate of the mold liquid level fluctuation within ±5 mm is > 85 % ( The compliance rates of liquid level fluctuation in the crystallizer with ± 5 mm is >85% (see, Hu’s [0042]). Hu’s passing rate of liquid level fluctuation in the crystallizer with ± 5 mm is overlapping with the as recited in the instant claim . Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filling date of the present invention , to have selected and produced a steel component from the teachings of Hu that falls within the instantly-claimed ranges, because “ 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)” [See MPEP § 2144.05.I]. It is to be noted, claim recites “and/or” in between the two different limitations, and use of “or” make these limitations as optional, and not required by the claim language. Therefore, with a teachings of the passing rate of liquid level fluctuation within ±5 mm , Hu already meets the entire claimed limitation. However, In addition, Hu also discloses a pass rate of the mold liquid level fluctuation within ±3 mm is > 25% ( The compliance rates of liquid level fluctuation in the crystallizer with ± 3mm is >25% (see, Hu’s [0042]). Hu’s passing rate of liquid level fluctuation in the crystallizer with ± 3 mm is overlapping with the as recited in the instant claim . Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filling date of the present invention , to have selected and produced a steel component from the teachings of Hu that falls within the instantly-claimed ranges, because “ 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)” [See MPEP § 2144.05.I]. Hu further discloses, with t he process control described above in this invention significantly improves the quality of the final product (see, Hu’s [004 3 ]). Therefore, it would have been further obvious to one of ordinary skill in the art before the effective filling date of the present invention , to have Hu’s teachings in view of Lyu to produce a titanium containing ultra-low carbon steel products with a high quality of the final product . Regarding Claim 11, all the discussions above claim 1 are applicable for claim 11 in addition, H u discloses during the cold rolling, a cold rolling defect rate caused by Al 2 O 3 are 0 % ( The cold rolling steel defect of the disclosed Hu’s embodiment , which the steel defects caused by Al 2 O 3 are 0% , see, Hu’s [0051]) . Hu’s defect rate caused by Al 2 O 3 is within the as recited in the instant claim . Regarding Claim 13, all the discussions above claim 1 and 2 are applicable for claim 13 , wherein Hu already discloses in the vacuum refining, before the decarburization treatment, the free oxygen content in the molten steel is adjusted to satisfy a mass ratio O/C=1.96 (a fter converter blowing, [%C] = 280ppm, [%O] = 550ppm; before vacuum treatment, and the vacuum decarburization started [0050] , therefore calculated O/C = 550/280 = 1.96 ) . Hu’s disclosed mass ratio O/C is within the as recited range of the instant claim. Claims 6 and 1 5 are rejected under 35 U.S.C. 103 as being unpatentable over Hu H antao , et.al. [ WO2021036974A1 ] (machine translation) (Hu hereafter) and in view of Lyu Zhiyong , et.al. [ CN108998613A ] (machine translation) (Lyu hereafter) as applied to claim 1, and further in view of Hu H antao , et.al. [ CN109402321A ] (machine translation , original provided in the IDS ) ( Hu’321A , hereafter). Regarding Claim 6, all the discussions above claim 1 are applicable for claim 1 in addition, Hu discloses in the primary converter refining, blowing is stopped, the free oxygen content in the molten steel is ≤ 500 ppm (a fter converter blowing, [%O] = 550ppm , see Hu’s [0050]) , which is within the as recited in the instant claim. But Hu is silent about a top-bottom combined blowing process is adopted. Hu is silent about “during tapping, when a tapping amount reaches 1/6 to 1/4, lime is added to a steel ladle in an amount of 1.6 to 3 kg/t steel; and when the tapping amount reaches 4/5 or more, aluminum slag is added to the steel ladle in an amount of 1.0 to 1.4 kg/t steel” Hu teaches after the tapping is completed, a composition of a steel ladle top slag is adjusted to: FeO+MnO ≤ 7.0wt% ( before vacuum treatment, the ladle top slag composition (%FeO) + (%MnO) ≤ 6.50, [ 0050]) , which is within the as recited in the instant claim. But Hu is silent about the CaO=40 to 50wt% . Lyu teaches oxygen is blown to reduce carbon and smelt into molten steel , but Lyu is also silent about a top-bottom combined blowing process is adopted. Lyu teaches lime is added to a steel ladle in an amount of 2-5 kg/t steel ( the steel is tapped into the ladle using slag-blocking and a fter the molten steel enters the argon blowing station, 2-5 kg/t of quicklime , see Lyu’s [0012]) , which is within the as recited in the instant claim. Lyu also teaches 0.5-1.5 kg/t of slag modifier are added see Lyu’s [0012]). But Lyu ’s is silent about “during tapping, when a tapping amount reaches 1/6 to 1/4, lime is added; and when the tapping amount reaches 4/5 or more, aluminum slag is added to the steel ladle in an amount of 1.0 to 1.4 kg/t steel”. However, Hu’321A teaches a production process of ultra-low carbon steel is hot metal pretreatment ( desulfurization and dephosphorization of molten iron ) – primary converter refining ( decarburization in converter ) - tapping of steel, modification of top slag in ladle – vacuum refining ( RH decarburization, deoxidation and composition fine-tuning ) - continuous casting - hot rolling - pickling - cold rolling (see Hu’321A ’s [0047]). Hu’321A then teaches in the primary converter refining, a top-bottom combined blowing process is adopted, wherein when blowing is stopped, the free oxygen content in the molten steel is 450-600 ppm ( In converter smelting, top and bottom blowing are adopted, and bottom blowing is maintained to ensure that the molten steel [O] = 450-600ppm and [C] = 0.01-0.05% when blowing stops see Hu’321A ’s claim 1 , [0019] ) . Hu’321A then teaches i n the smelting of ultra-low carbon steel, the oxygen (free oxygen and combined oxygen) added during converter smelting is the main oxygen source in the entire smelting process. Subsequently, during the tapping process, molten steel and slag containing a large amount of oxygen enter the ladle. I n vacuum cyclic refining for decarburization, the oxygen in molten steel forms oxide inclusions during subsequent deoxidation, which is detrimental to the quality of the steel. Therefore, the converter need to maintain good bottom blowing operation (top and bottom re-blowing) to ensure that the molten steel [O] = 450-600ppm when blowing stop ( see Hu’321A ’s [0019] ) . Hu’321A ’s process is directed to the production of ultra - low-carbon steel and therefore, analogous to the instant claim and Hu as well as Lyu . Therefore, it would have been further obvious to one of ordinary skill in the art before the effective filling date of the present invention , to have Hu’321A ’s teachings of adaptation of top and bottom blowing that requires the converter to maintain good bottom blowing operation to modify Hu’s method in combination with Lyu to ensure that the molten steel oxygen content to a controlled amount that is sufficient for decarburization refining , while reducing the oxide inclusions during subsequent deoxidation, to produce high the quality of the steel. It is to be noted, claim recites “and/or” in between three different limitations, and use of “or” make these limitations as optional, and not required by the claim language. Therefore, with a teachings of a top-bottom combined blowing process is adopted, wherein when blowing is stopped, the free oxygen content in the molten steel is 450-600 ppm, Hu’ 321A meets the entire claimed limitation. In addition, Hu’321A teaches it is guaranteed that the slag thickness of a steel ladle is smaller than or equal to 50 mm in the steel tapping process, 2.0-5.0 kg of lime is added into per ton of steel in the early stage of steel tapping, 0.5-2 kg of an Al quality modification agent is added in per ton of steel at the last stage of steel tapping (see Hu’321A ’s abstract). Hu’321A also teaches the tapping process employs a sliding plate slag-blocking operation to ensure that the ladle slag thickness is ≤50mm (without added slag). 2.0-5.0 kg/t steel of lime is added in the early stage of tapping, and 0.5-2 kg/t steel of Al-based modifier is added in the final stage to modify and deoxidize the ladle top slag to maintain the composition of the ladle top slag before vacuum treatment, and oxidizing components ( wt. % FeO) + ( wt. % MnO) ≤ 8. ( see Hu’321A ’s [0019] ) . According to the Example 1, line 24 to 26 of the instant specification of the discloses, “ In the early stage of tapping ” is described as when the tapping amount reached 1/5, and “ the final stage ” is described as when the tapping amount reached 9/10 ”, as Hu’321A teaches similar terminology, “ lime is added in the early stage of tapping ” and “ aluminum slag is added in in the final stage ”, therefore, Hu’321A ’s lime is added when the tapping amount reached 1/5 , and aluminum slag is added when the tapping amount reached 9/10 . Hu’321A slag tapping amount as well as lime and aluminum slag are with in the as recited in the instant claim . Regarding Claim 15, all the discussions above claim 1 and 6 are applicable for claim 15 , but Hu is silent about “during tapping, when a tapping amount reaches 1/6 to 1/4, lime is added to a steel ladle in an amount of 1.6 to 3 kg/t steel; and when the tapping amount reaches 4/5 or more, aluminum slag is added to the steel ladle in an amount of 1.0 to 1.4 kg/t steel”. Lyu teaches lime is added to a steel ladle in an amount of 2-5 kg/t steel ( the steel is tapped into the ladle using slag-blocking and a fter the molten steel enters the argon blowing station, 2-5 kg/t of quicklime , see Lyu’s [0012]), which is within the as recited in the instant claim. Lyu also teaches 0.5-1.5 kg/t of slag modifier are added see Lyu’s [0012]). But Lyu’s is silent about “during tapping, when a tapping amount reaches 1/6 to 1/4, lime is added; and when the tapping amount reaches 4/5 or more, aluminum slag is added to the steel ladle in an amount of 1.0 to 1.4 kg/t steel”. However, Hu’321A teaches it is guaranteed that the slag thickness of a steel ladle is smaller than or equal to 50 mm in the steel tapping process, 2.0-5.0 kg of lime is added into per ton of steel in the early stage of steel tapping, 0.5-2 kg of an Al quality modification agent is added in per ton of steel at the last stage of steel tapping (see Hu’321A ’s abstract). Hu’321A also teaches the tapping process employs a sliding plate slag-blocking operation to ensure that the ladle slag thickness is ≤50mm (without added slag). 2.0-5.0 kg/t steel of lime is added in the early stage of tapping, and 0.5-2 kg/t steel of Al-based modifier is added in the final stage to modify and deoxidize the ladle top slag to maintain the composition of the ladle top slag before vacuum treatment, and oxidizing components ( wt. % FeO) + ( wt. % MnO) ≤ 8. ( see Hu’321A ’s [0019] ) . According to the Example 1, line 24 to 26 of the instant specification of the discloses, “ In the early stage of tapping ” is described as when the tapping amount reached 1/5, and “ the final stage ” is described as when the tapping amount reached 9/10 ”, as Hu’321A teaches similar terminology, “ lime is added in the early stage of tapping ” and “ aluminum slag is added in in the final stage ”, therefore, Hu’321A ’s lime is added when the tapping amount reached 1/5 , and aluminum slag is added when the tapping amount reached 9/10 . Hu’321A slag tapping amount as well as lime and aluminum slag are within the as recited in the instant claim . Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Hu H antao , et.al. [ WO2021036974A1 ] (machine translation) (Hu hereafter) and in view of Lyu Zhiyong , et.al. [ CN108998613A ] (machine translation) (Lyu hereafter) as applied to claim 1, and further in view of Hu H antao , et.al. [ CN109554605A ] (machine translation, provided in the IDS) (Hu’605A hereafter) Regarding Claim 12, all the discussions above claim 1 are applicable for claim 12 in addition, Hu discloses a fter RH vacuum decarburization is completed, Ti is added , and the amount of Ti added is the lower limit of the Ti content range of the finished product specification (see Hu’s [0012] ) and emphasizes to controlling the Ti content (Ti/Al ratio) added for deoxidation to control the final inclusion composition (see Hu’s [0008] ) . But Hu is silent about a titanium consumption is less than 0.7 kg/t steel. However, Hu’605A teaches a method for controlling oxide inclusions in the production of ultra-low carbon steel using a process includes the steps of primary convertor refining, ( see Hu’605A ’s claim 1 step 1) LD converter smelting ) , vacuum refining ( step 2) the molten steel enters the RH furnace for RH refining, vacuum decarburization is performed in the RH furnace. Al is added to deoxidize the molten steel. Then, refining agent is added at a rate of 0.3-2 kg/t of steel. After the molten steel is circulated purely for 2-10 minutes, alloy is added to adjust the main composition of the molten steel, wherein t he main components of the refining agent are as follows: CaO: 50-60wt%, Al 2 O 3 : 30-40wt%, MgO: 2-6wt%, SiO 2 ≤3wt%, TiO 2 <0.08wt%, FeO≤1wt%, H 2 O≤0.5wt% (see Hu’605A ’s claim 1 step 2). The total amount of TiO 2 in the refining agent is calculated from 0.08% of 0.3-2 kg/t of steel, will be 0.024 – 0.16 kg/t of steel, therefore, the amount of Ti=(47.87 / 79.87)× m ass of TiO 2 , or, the amount of Ti ≈ 0.599 × m ass of TiO 2 and the therefore, amount of Ti ≈ 0.014 to 0.096 kg/t, which is within the as recited in the instant claim. Hu’605A teaches an example wherein, Al is added to deoxidize the molten steel , i mmediately afterwards, 1.04 kg/t steel of refining agent is added wherein the composition of TiO 2 is less than 0.02 % (see Hu’605A ’s [003 9 ] and Table 1 in the original discloser). The total amount of TiO 2 in the refining agent is calculated from 0.02% of 1.04 kg/t of steel, will be 0.0 208 kg/t of steel, therefore, the amount of Ti ≈ 0.0 125 kg/t, which is also within the as recited in the instant claim and t he main components of the finished product are: [C] = 0.0014%, [Si] = 0.005%, [Mn] = 0.16%, [Al] = 0.042%, [Ti] = 0.051%, [P] ≤ 0.015%, [S] ≤ 0.01%, [N] ≤ 0.003% (see Hu’605A ’s [0039]). Hu’605A ’s steel composition is within the claimed composition as well as Hu’s steel . Hu’605A further teaches TiO 2 has a very high melting point and exists as a solid phase in the slag formed by refining agents, resulting in poor slag fluidity, which is not conducive to the adsorption and absorption of AlNER34 and ONER35, so it should be restricted (see Hu’605A ’s [0023] ) and controlling oxide inclusions in the production of ultra-low carbon steel . Hu’605A ’s process thereby reduc ed the number of inclusions in the billet, improv es the yield of liquid level fluctuations in the continuous casting crystallizer, reducing the incidence of inclusion-related defects during rolling, and lowering the oxygen content of the finished product and demonstrating a significant cleaning effect on the molten steel , and the cold rolling blockage rate is reduced from 3.05% to 0.99%, showing significant improvement (see Hu’605A ’s [0010]). Hu’605A ’s process is directed to the production of ultra - low-carbon steel and therefore, analogous to the instant claim and Hu as well as Lyu. Therefore, it would have been further obvious to one of ordinary skill in the art before the effective filling date of the present invention , to have Hu’605A ’s teachings of deoxidizing with Al and limiting Ti content in the refining agent to modify Hu’s deoxidation and refining process in combination with Lyu to ensure the final composition and lowering the oxygen content of the finished product while demonstrating a significant cleaning effect on the molten steel reducing inclusion-related defects during rolling . Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Yang Kehzhi, et.al. [CN112342333A] (machine translation, original provided in the IDS) teaches a high-efficiency, low-oxygen, ultra-low-carbon steel production method employs a process of hot metal pretreatment desulfurization, converter smelting, argon blowing station, RH refining, and continuous casting. The process, after desulfurization , the scrap steel is charged into the converter has a hot metal and the blowing method is top and bottom combined blowing, with a blowing time of 1 f rom 0 to 16 minutes, the final oxygen content in the converter is 200 to 400 ppm . A top slag modifier is added to the argon blowing station to ensure that the FeO+MnO content in the top slag is ≤8% by mass percentage. Forced decarburization is adopted in the RH process. The gas flow rate is increased during the decarburization, deoxidation, and alloying periods to promote the circulation of molten steel. After adding alloy for 2 to 3 minutes, the pure circulation is switched to a low flow rate to promote the flotation and removal of inclusions. the percentage of the bright surface of the slag removal (claim 1 and 2). 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