DETAILED ACTION
Response to Amendment
The Amendment filed 17 June 2026 has been entered. Claims 1-7 and 9-11 remain pending in the application. Claim 8 has been canceled. No new claims have been added. Applicant's amendments to the claims have overcome the 112(b) rejections previously set forth in the Non-Final Rejection mailed 18 March 2026.
Priority
Acknowledgment is made of applicant’s claim for foreign priority under 35 U.S.C. 119 (a)-(d).
Information Disclosure Statement
Information disclosure statement(s) (IDS) were between 31 October 2023 and 09 October 2025. The submissions are in compliance with the provisions of 37 CFR 1.97. Accordingly, the IDS were considered by the examiner.
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 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over JP2020520408 of Kuran in view of KR100433591 of Nakagawa, and further in view of US3807714 of Hollyer.
Claim 1 claims a dew point control method for a continuous annealing furnace comprising a plurality of nozzles provided on a top wall and side walls of the furnace and configured to supply gas along a furnace inner wall, wherein the gas supplied from the plurality of nozzles is dry gas, the method comprising stopping or reducing supply of humidified gas into the furnace, and supplying dry gas along the furnace inner wall of the continuous annealing furnace in the continuous annealing furnace, wherein the plurality of nozzles is slit nozzles or wiping nozzles, and each of the plurality of nozzles injects dry gas toward the furnace inner wall at 50 or more and 450 or less with respect to the furnace inner wall.
Kuran teaches a section and method for cooling a continuous line combining dry cooling and wet cooling in the same field of endeavor as the claimed invention. Kuran discloses a cooling section for a continuous annealing furnace, Para[0002]. Kuran teaches a drying and purging system set up to eject a mixture of gas and liquid that helps limit transition times between a product that requires the use of the wet area and a product that does not need to be cooled by the wet area, Para[0026]. Kuran discloses a nozzle configured to inject a liquid or a mixture of gas and liquid, Para[0010]. Kuran teaches that the drying and purging system can include equipment configured to heat the walls, Para[0027]. While Kuran does not teach the specific numerical limitation of 5° to 45°, Kuran discloses that the system may include nitrogen knives directed downward in the wet cooling area configured to blow nitrogen onto an inner wall, Para[0028]. Figures 1 and 2 of Kuran also show that the gas knives, 17, are angled with respect to the inner wall. Kuran does not specifically teach a slit or wiping nozzle.
Nakagawa teaches a continuous heat treatment apparatus for metal strips in the same field of endeavor as the claimed invention. Nakagawa discloses that in the above-described embodiment, only the case where the gas injected from the preheating zone into the strip is air is described. However, any gas may be used as the gas injected into the strip in this preheating zone. Further, the metal strip to be continuously heat-treated is not limited to the strip. Also, the spraying method to the strip may be a slit nozzle or a multi-hole type, Para[0104]. Therefore, it would be obvious to one of ordinary skill in the art to use the slit nozzle as taught by Nakagawa in the dew point control method disclosed by Kuran in order to continuously heat treat the metal object.
Hollyer discloses an apparatus for the quenching of pipe in a similar field of endeavor as the claimed invention. Hollyer teaches nozzles dispensing the quenching medium against the pipe, Para[0005]. Hollyer discloses that it has been found that this arrangement whereby the angle included between the curtain and the pipe wall at contact is less than 45° and can be as small as 10° provides a greater duration of contact between the water and the wall of the pipe, reduced reflection, and constantly greater heat transfer to the water, Para[0020]. This overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Therefore, based on the teachings of Kuran and Hollyer, it would be obvious to one of ordinary skill in the art to place the nitrogen knives so that an angle formed between the dry gas injected from inside the furnace toward the furnace inner wall and the furnace inner wall in the continuous annealing furnace is 5° or more and 45° or less in order to reduce reflection and achieve greater heat transfer.
Thus, Kuran in view of Nakagawa and Hollyer covers all limitations of claim 1.
Claim 7 claims a continuous annealing furnace comprising a plurality of nozzles provided on a top wall and side walls of the furnace and configured to supply gas along a furnace inner wall, wherein the gas supplied from the plurality of nozzles is dry gas, the plurality of nozzles is slit nozzles or wiping nozzles, and each of the plurality of nozzles injects dry gas towards the furnace inner wall at 50 or more and 450 or less with respect to the furnace inner wall.
Kuran teaches a section and method for cooling a continuous line combining dry cooling and wet cooling in the same field of endeavor as the claimed invention. Kuran discloses a cooling section for a continuous annealing furnace, Para[0002]. Kuran teaches a drying and purging system set up to eject a mixture of gas and liquid that helps limit transition times between a product that requires the use of the wet area and a product that does not need to be cooled by the wet area, Para[0026]. Kuran discloses a nozzle configured to inject a liquid or a mixture of gas and liquid, Para[0010]. Kuran teaches that the drying and purging system can include equipment configured to heat the walls, Para[0027]. While Kuran does not teach the specific numerical limitation of 5° to 45°, Kuran discloses that the system may include nitrogen knives directed downward in the wet cooling area configured to blow nitrogen onto an inner wall, Para[0028]. Figures 1 and 2 of Kuran also show that the gas knives, 17, are angled with respect to the inner wall. Kuran does not specifically teach a slit or wiping nozzle.
Nakagawa teaches a continuous heat treatment apparatus for metal strips in the same field of endeavor as the claimed invention. Nakagawa discloses that in the above-described embodiment, only the case where the gas injected from the preheating zone into the strip is air is described. However, any gas may be used as the gas injected into the strip in this preheating zone. Further, the metal strip to be continuously heat-treated is not limited to the strip. Also, the spraying method to the strip may be a slit nozzle or a multi-hole type, Para[0104]. Therefore, it would be obvious to one of ordinary skill in the art to use the slit nozzle as taught by Nakagawa in the dew point control method disclosed by Kuran in order to continuously heat treat the metal object.
Hollyer discloses an apparatus for the quenching of pipe in a similar field of endeavor as the claimed invention. Hollyer teaches nozzles dispensing the quenching medium against the pipe, Para[0005]. Hollyer discloses that it has been found that this arrangement whereby the angle included between the curtain and the pipe wall at contact is less than 45° and can be as small as 10° provides a greater duration of contact between the water and the wall of the pipe, reduced reflection, and constantly greater heat transfer to the water, Para[0020]. This overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Therefore, based on the teachings of Kuran and Hollyer, it would be obvious to one of ordinary skill in the art to place the nitrogen knives so that an angle formed between the dry gas injected from inside the furnace toward the furnace inner wall and the furnace inner wall in the continuous annealing furnace is 5° or more and 45° or less in order to reduce reflection and achieve greater heat transfer.
Thus, Kuran in view of Nakagawa and Hollyer covers all limitations of claim 7.
Claims 2 and 9 are rejected under 35 U.S.C. 103 as being unpatentable over JP2020520408 of Kuran in view of KR100433591 of Nakagawa and US3807714 of Hollyer, as cited above, further in view of US2872173 of Munker.
Claim 2 further limits claim 1 by claiming that a temperature of the furnace inner wall of the continuous annealing furnace is at least 30°C higher than a furnace atmosphere temperature in the continuous annealing furnace.
Kuran teaches that the drying and purging system can include equipment configured to heat the walls, Para[0027]. Kuran discloses that the system may include nitrogen knives directed downward in the wet cooling area configured to blow nitrogen onto an inner wall, Para[0028]. While Kuran does not teach the specific numerical limitation of at least 30°C higher, Kuran teaches the claimed device. When the prior art device is the same as a device described in the specification for carrying out the claimed method, it can be assumed the device will inherently perform the claimed process, see MPEP 2112.02.
Munker discloses a method and apparatus for heat treating materials in a continuous operating furnace in the same field of endeavor as the claimed invention. Munker teaches that for preventing any cooling of the material to be treated in the measuring zone, it is preferable to keep the temperature of the walls of the furnace somewhat higher than the temperature of the material to be treated. In the case of annealing furnaces, a difference in temperature of about 30 to 50' C has proven to be satisfactory, Para[0064]. This overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Therefore, based on the teachings of Kuran and Munker, it would be obvious to one of ordinary skill in the art to heat the furnace inner wall to at least 30°C higher than the furnace atmosphere temperature in order to prevent cooling of the material to be treated. Thus, Kuran in view of Nakagawa, Hollyer, and Munker covers all limitations of claim 2.
Claim 9 further limits claim 7 by comprising a heating mechanism configured to heat the furnace inner wall to a temperature at least 30 °C higher than a furnace atmosphere temperature.
Kuran teaches that the drying and purging system can include equipment configured to heat the walls, Para[0027]. Kuran discloses that the system may include nitrogen knives directed downward in the wet cooling area configured to blow nitrogen onto an inner wall. While Kuran does not teach the specific numerical limitation of at least 30°C higher, Kuran teaches the claimed device. When the prior art device is the same as a device described in the specification for carrying out the claimed method, it can be assumed the device will inherently perform the claimed process, see MPEP 2112.02.
Munker discloses a method and apparatus for heat treating materials in a continuous operating furnace in the same field of endeavor as the claimed invention. Munker teaches that for preventing any cooling of the material to be treated in the measuring zone, it is preferable to keep the temperature of the walls of the furnace somewhat higher than the temperature of the material to be treated. In the case of annealing furnaces, a difference in temperature of about 30 to 50' C has proven to be satisfactory, Para[0064]. This overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Therefore, based on the teachings of Kuran and Munker, it would be obvious to one of ordinary skill in the art to heat the furnace inner wall to at least 30°C higher than the furnace atmosphere temperature in order to prevent cooling of the material to be treated. Thus, Kuran in view of Nakagawa, Hollyer, and Munker covers all limitations of claim 9.
Claims 3 and 10 are rejected under 35 U.S.C. 103 as being unpatentable over JP2020520408 of Kuran in view of KR100433591 of Nakagawa and US3807714 of Hollyer, as cited above, further in view of JP61253327 of Shogo.
Claim 3 further limits claim 1 by claiming that a furnace dew point is changed from a dew point of 5 °C or more to a dew point of less than 0 °C.
Kuran teaches a drying and purging system that changes the dew point within the furnace, Para[0024]. While Kuran does not specifically teach the numerical limitations for the dew point recited in claim 3, Kuran teaches the claimed device. When the prior art device is the same as a device described in the specification for carrying out the claimed method, it can be assumed the device will inherently perform the claimed process, see MPEP 2112.02.
Shogo discloses how to lower the dew point of a heating furnace in the same field of endeavor as the claimed invention. Shogo teaches a method where operation starts when the dew point reaches around 115 °C and goes to a stable dew point of -40°C, Para[0003]. Shogo teaches that an object of the present invention is to provide a dew point lowering method that shortens the time required for lowering the dew point, advances the start of furnace operation, and greatly improves operational efficiency, Para[0004]. Therefore, based on the teachings of Kuran and Shogo, it would be obvious to one of ordinary skill in the art to change the dew point of 5 °C or more to a dew point of less than 0 °C in order to advance the start of furnace operation and greatly improve operational efficiency. Thus, Kuran in view of Nakagawa, Hollyer, and Shogo covers all limitations of claim 3.
Claim 10 further limits claim 7 by claiming a continuous hot-dip galvanizing line comprising: the continuous annealing furnace according to claim 7; and a coating apparatus that follows the continuous annealing furnace.
While Kuran teaches a continuous annealing furnace, Kuran does not specifically mention a hot-dip galvanizing line.
Shogo teaches that in a continuous hot-dip galvanizing process, it is essential that the material be subjected to heat treatment for annealing and cleaning purposes before plating. In such heating furnaces, when the furnace is newly built or renovated, the refractories contain a large amount of moisture, and the refractories also absorb moisture when the furnace is stopped for a long period of time for repairs or the like, Para[0002]. Therefore, it would be obvious to one of ordinary skill in the art to use the continuous annealing furnace disclosed in Kuran in a hot-dip galvanizing process because in such heating furnaces the refractories contain a large amount of moisture. Thus, Kuran in view of Nakagawa, Hollyer, and Shogo covers all limitations of claim 10.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over JP2020520408 of Kuran in view of KR100433591 of Nakagawa and US3807714 of Hollyer, as cited above, further in view of CN104673989 of Qiu .
Claim 4 further limits claim 1 by claiming that a jet velocity of the dry gas impinging on the furnace inner wall is controlled to be 0.8 m/s or more.
Kuran does not teach a specific jet velocity.
Qiu discloses a gas sealing device and method for soaking zone of continuous annealing furnace in the same field of endeavor as the claimed invention. Qiu teaches nozzles with hot gas injected through them, Para[0011]. Qiu discloses a jet velocity of 30m/s to 70m/s, Para[0011]. This overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Qui teaches that the technical problem to be solved by the present invention is to provide a continuous annealing furnace soaking section gas sealing device and method, which can effectively prevent the rise of the hot gas flow in the soaking section and stabilize the furnace pressure of the soaking section, Para[0006]. Therefore, it would be obvious to one of ordinary skill in the art to use a jet velocity greater than 0.8 m/s to stabilize the furnace pressure.
Thus, Kuran in view of Nakagawa, Hollyer, and Qiu covers all limitations of claim 4.
Claims 5 and 6 are rejected under 35 U.S.C. 103 as being unpatentable over JP2020520408 of Kuran in view of KR100433591 of Nakagawa and US3807714 of Hollyer, as cited above, further in view of WO2015129202 of Takeda.
Claim 5 further limits claim 1 by claiming a continuous annealing method for a steel sheet, the method comprising controlling a furnace dew point using the dew point control method according to claim 1.
While Kuran teaches an invention for a continuous annealing or galvanizing line for steel strips, Kuran does not disclose steel sheets.
Takeda teaches a method for controlling dew point of reduction furnace, and reduction furnace in the same field of endeavor as the claimed invention. Takeda discloses that in recent years, in the fields of automobiles, household appliances, building materials, etc., there is an increasing demand for high-tensile strength steel that can be used for weight reduction of structures and the like. As a high-tensile strength steel, for example, a steel sheet having Si excellent in hole expandability by containing Si in steel, or a steel plate having Si or Al to retain residual γ (retained γ) are easy to form and a steel sheet with good ductility is obtained, Para[0002]. Takeda also teaches continuous hot dip galvanizing, Para[0011]. Therefore, it would be obvious to one of ordinary skill in the art to control the furnace dew point as disclosed in Kuran for a continuous annealing method for a steel sheet because of the increase in demand for high-tensile strength steel sheets taught by Takeda. Thus, Kuran in view of Nakagawa, Hollyer, and Takeda covers all limitations of claim 5.
Claim 6 further limits claim 5 by claiming a steel sheet manufacturing method comprising manufacturing a high-tensile-strength steel sheet, a hot-dip galvanized steel sheet, or a galvannealed steel sheet using the continuous annealing method according to claim 5.
While Kuran teaches an invention for a continuous annealing or galvanizing line for steel strips, Kuran does not disclose steel sheets or hot-dip galvanizing.
Takeda teaches a method for controlling dew point of reduction furnace, and reduction furnace in the same field of endeavor as the claimed invention. Takeda discloses that in recent years, in the fields of automobiles, household appliances, building materials, etc., there is an increasing demand for high-tensile strength steel that can be used for weight reduction of structures and the like. As a high-tensile strength steel, for example, a steel sheet having Si excellent in hole expandability by containing Si in steel, or a steel plate having Si or Al to retain residual γ (retained γ) are easy to form and a steel sheet with good ductility is obtained, Para[0002]. Takeda also teaches continuous hot dip galvanizing, Para[0011]. Therefore, it would be obvious to one of ordinary skill in the art to control the furnace dew point as disclosed in Kuran for a continuous annealing method for a hot dipped galvanized steel sheet because of the increase demand for high-tensile strength steel sheets taught by Takeda. Thus, Kuran in view of Nakagawa, Hollyer, and Takeda covers all limitations of claim 6.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over JP2020520408 of Kuran in view of KR100433591 of Nakagawa and US3807714 of Hollyer, as cited above, further in view of WO2015129202 of Takeda and WO2018003407 of Maeda.
Claim 11 further limits claim 7 by claiming a galvannealing line comprising: the continuous annealing furnace according to claim 7; a coating apparatus that follows the continuous annealing furnace; and an alloying furnace.
Kuran discloses that the cooling section of the present invention is capable of producing steel with a high degree of mechanical properties that can undergo a galvanizing step directly upon exiting the cooling section without the need for intermediate chemical treatments, Para[0011]. This corresponds to the claimed coating apparatus. Kuran does not specifically teach galvannealing or an alloying furnace.
Takeda teaches a galvannealed steel sheet, Para[0003, 0034, 0039]. Takeda discloses that in recent years, in the fields of automobiles, household appliances, building materials, etc., there is an increasing demand for high-tensile strength steel that can be used for weight reduction of structures and the like. As a high-tensile strength steel, for example, a steel sheet having Si excellent in hole expandability by containing Si in steel, or a steel plate having Si or Al to retain residual γ (retained γ) are easy to form and a steel sheet with good ductility is obtained, Para[0002]. Therefore, it would be obvious to one of ordinary skill in the art to control the furnace dew point as disclosed in Kuran for a continuous annealing method for a hot dipped galvannealed steel sheet because of the increase demand for high-tensile strength steel sheets taught by Takeda.
Maeda teaches high strength galvannealed steel sheet and production method thereof in the same field of endeavor as the claimed invention. Maeda teaches an alloying furnace after the annealing, Para[0002]. Maeda discloses that in recent years, in the fields of automobiles, household appliances, building materials, etc., surface treated steel plates imparting rust prevention properties to material steel plates, among which alloying hot dip galvanized steel sheets having excellent rust prevention properties are used, Para[0002]. Therefore, it would be obvious to one of ordinary skill in the art to use the dew point control method disclosed in Kuran for a continuous annealing method followed by an alloying furnace in order to alloy the steel to impart rust prevention properties.
Thus, Kuran in view of Nakagawa, Hollyer, Takeda and Maeda covers all limitations of claim 11.
Response to Arguments
Applicant's arguments filed 17 June 2026 have been fully considered but they are not persuasive. Applicant argues that (remarks, page 10 of 14) primary reference Kuran is distinguished from the instant application in that the nitrogen knives are not provided on the top wall of the wet cooling area of the continuous annealing line. Examiner asserts that while Kuran does not teach the specific numerical limitation of 5° to 45°, Kuran discloses that the system may include nitrogen knives directed downward in the wet cooling area configured to blow nitrogen onto an inner wall, Para[0028]. Figures 1 and 2 of Kuran also show that the gas knives, 17, are angled with respect to the inner wall. Additionally, Kuran teaches that the drying and purging system can include equipment configured to heat the walls of the wet cooling area. This makes it possible to limit condensation in the wet cooling area or shorten the drying time in the wet cooling area. Heating is preferably done through the addition of elements that heat by conduction or radiation, Para[0027]. Therefore, one of ordinary skill in the art would be able to consider the downward direction of the knives taught by Kuran along with figures 1 and 2 and reasonably conclude that the knives must be placed on the top wall or top of the side wall of the furnace in order for them to heat the walls and limit condensation and shorten the drying time as taught by Kuran. Thus, Kuran does teach nozzles provided on the top wall of the continuous annealing furnace.
Applicant argues that (remarks, pages 10 and 11 of 14) the configuration of the apparatus of Hollyer in achieving the desired injection angle is completely different between Kuran and Hollyer as Hollyer includes a shroud on the dispensing head to redirect the curtain of liquid. Applicant argues that the overlapping angle taught by Hollyer is not the injection angle per se of the angle of liquid. Rather, it is the contact angle with the inner wall of the pipe that has been modified by placement of the shroud. This is not found persuasive as one of ordinary skill in the art would be able to consider the contact angle of the curtain of liquid with respect to the inner wall of the pipe and reasonably compare that to the injection angle of the gas nozzle of Kuran with respect to the inner wall of the furnace because both Kuran and Hollyer teach an injected fluid used to transfer heat to or from a wall. The overlapping angle taught by Hollyer is the angle at which the fluid is positioned with respect to the wall directly before it contacts the wall. It would be obvious to apply this angle to the fluid being used to transfer heat from the wall directly before it is injected towards the wall in Kuran. Hollyer’s overlapping angle could be applied to Kuran without adding a shroud.
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.
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/Keith D. Hendricks/Supervisory Patent Examiner, Art Unit 1733
/JACOB BENJAMIN STILES/Examiner, Art Unit 1733
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