DETAILED ACTION
Response to Amendment
The Amendment filed 1/16/26 has been entered. Claims 11-22 remain pending in the application. Claim(s) 1-10 have been canceled.
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.
Language from the reference(s) is shown in quotations. Limitations from the claims are shown in quotations within parenthesis. Examiner explanations are shown in italics.
Claims 11-16 and 21-22 are rejected under 35 U.S.C. 103 as being unpatentable over Zaizen et al. (EP 3378959 B1), previously cited.
Regarding claims 11, 13, and 15-16, Zaizen teaches “a method of increasing a heating rate in recrystallization annealing, and that this method is often used in the production of grain-oriented electrical steel sheets” (which reads upon “a method for recrystallization annealing of a non-grain-oriented electric strip”, as recited in the instant claim; paragraph [0004]). Zaizen teaches “a continuous annealing facility heating the sheet” (which reads upon “in a continuous annealing and coating line (1), comprising”, as recited in the instant claim; paragraph [0074]). Zaizen teaches that “the steel sheet after the finish annealing is coated with an insulation coating, if necessary, to form a product sheet” (which reads upon “and coating line (1)”, as recited in the instant claim; paragraph [0072]). Zaizen teaches that “the induction heating may be conducted by dividing into plural segments” (paragraph [0065]). Zaizen teaches that “in order to reduce the equipment cost for the induction heating, the steel sheet is preheated by a radiation heating before the induction heating and then the induction heating may be applied only to a temperature range of the rapid heating” (which reads upon “initially heating the electric strip (2) by a first continuous furnace (3) thereafter heating the electric strip (2) in an induction furnace”, as recited in the instant claim; paragraph [0065]). Zaizen teaches that “the upper limit of the preheating temperature is preferable to be set to not higher than 500°C from a viewpoint of recovery prevention” (which reads upon “initially heating the electric strip (2) by a first continuous furnace (3) to a temperature of at least 300 °C”, as recited in the instant claim; which reads upon “wherein the electric strip (2) is heated in the first continuous furnace (3) to a temperature of at most 500 °C”, as recited in instant claim 13; paragraph [0065]).
It has been held that obviousness exists where the claimed ranges overlap or lie inside ranges disclosed by the prior art. 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). Here, the claimed range of at least 300 °C overlaps the range disclosed by the prior art of not higher than 500°C. Accordingly, the prior art renders the claim obvious.
Zaizen teaches that “it is necessary to set an average heating rate from 600°C to 740°C to not less than 50°C/sec, and that the more preferable heating rate is not less than 100°C/sec” (which reads upon “thereafter heating the electric strip (2) in an induction furnace (5) to a temperature of at least 680°C at a heating rate of at least 80 K/s”, as recited in the instant claim; paragraph [0064]; 1 °C/sec = 1 K/s). Zaizen teaches that “after the end of the induction heating, the radiation heating is performed up to a predetermined soaking temperature” (which reads upon “thereafter heating the electric strip (2) in a second continuous furnace”, as recited in the instant claim; paragraph [0067]). Zaizen teaches that “the heating rate by the radiation heating is preferable to be not less than 5°C/sec from a viewpoint of promoting the recrystallization” (paragraph [0068]). Zaizen teaches that “a soaking temperature after being heated by the radiation heating falls in a range of 900°C to 1100°C” (which reads upon “thereafter heating the electric strip (2) in a second continuous furnace (8) to a temperature of at least 820°C”, as recited in the instant claim; paragraph [0070]). Zaizen teaches that “the average heating rate up to a soaking temperature in the radiation heating furnace is set to 18°C/sec” (which reads upon “at a heating rate of at most 20 K/s”, as recited in the instant claim; paragraph [0075]).
Zaizen teaches that “an average heating rate in a temperature range of lower than 600°C is not particularly defined, but is preferably set to not less than 10°C/sec from a viewpoint of the productivity” (paragraph [0064]). Zaizen is silent regarding a heating rate of at most 60 K/s (or 50, or 30, as in claims 15-16) in the preheat radiant furnace. Zaizen teaches that “the average heating rate up to a soaking temperature in the radiation heating furnace is set to 18°C/sec” (paragraph [0075]; 1 °C/sec = 1 K/s). Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use a heating rate of 18°C/sec in the radiation preheating furnace because Zaizen teaches a heating rate of 18°C/sec in the radiation soaking furnace and both furnaces are radiation furnaces, which reads on a heating rate of at most 60 K/s (or 50, or 30, as in claims 15-16). Additionally, the prescribed heating rate of 18°C/sec falls within the guidance for the radiation preheating furnace of preferably not less than 10°C/sec from a viewpoint of the productivity.
Zaizen is silent regarding thereby evaporating fluids present on the strip, preventing condensation of residues, and producing a residue-free electric strip.
It is noted that thereby evaporating fluids present on the strip, preventing condensation of residues, and producing a residue-free electric strip is a result of the claimed method steps, rather than a separate method step.
Zaizen teaches that “the upper limit of the preheating temperature is preferable to be set to not higher than 500°C from a viewpoint of recovery prevention” (which reads upon “initially heating the electric strip by a first continuous furnace to a temperature of at least 300 °C”; paragraph [0065]).
Modified Zaizen teaches a heating rate of 18°C/sec which reads on a heating rate of at most 60 K/s (or 50, or 30, as in claims 15-16), as stated above.
The instant specification teaches that “The method is characterized by the fact that the non-grain-oriented electric strip is initially heated before the induction furnace via a first continuous furnace to a temperature of at least 300°C at a heating rate of at most 60 K/s. As a result, residues such as water, oils and other fluids that remain on the strip surface of the electric strip from the pre-process can be evaporated particularly gently and without leaving any residue. Due to the high temperature of at least 300°C inside the first continuous furnace, condensation of the residues is also effectively prevented.” (paragraph [0009]).
Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that following the method of modified Zaizen, including heating to at least 300°C at a heating rate of at most 60 K/s, such as 18 K/s, would necessarily result in evaporating fluids present on the strip, preventing condensation of residues, and producing a residue-free electric strip. The burden is on Applicant to prove otherwise. In re Best, Bolton, and Shaw, 195 USPQ 430 (CCPA 1977).
Regarding claim 12, Zaizen teaches the method of claim 11 as stated above. Zaizen teaches that “it is preferable to conduct the final cold rolling in the one cold rolling or two or more cold rollings interposing an intermediate annealing therebetween by adjusting the temperature of the steel sheet on the exit side of the cold rolling machine to not higher than 180°C” (paragraph [0057]). Zaizen teaches that “in order to reduce the equipment cost for the induction heating, the steel sheet is preheated by a radiation heating before the induction heating and then the induction heating may be applied only to a temperature range of the rapid heating” (paragraph [0065]). Zaizen teaches that “the upper limit of the preheating temperature is preferable to be set to not higher than 500°C” (paragraph [0065]). As stated above, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use a heating rate of 18°C/sec in the radiation preheating furnace because Zaizen teaches a heating rate of 18°C/sec in the radiation soaking furnace and both furnaces are radiation furnaces. Assuming a preheat temperature of 450 °C (not higher than 500°C), the dwell time would be (450 °C – 180°C) / 18°C/sec = 15 seconds.
Regarding claim 14, Zaizen teaches the method of claim 11 as stated above. Zaizen teaches that “the upper limit of the preheating temperature is preferable to be set to not higher than 500°C from a viewpoint of recovery prevention” (paragraph [0065]). It has been held that obviousness exists where the claimed ranges overlap or lie inside ranges disclosed by the prior art. 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). Here, the claimed range of at most 450 °C lies inside the range disclosed by the prior art of not higher than 500°C. Accordingly, the prior art renders the claim obvious.
Regarding claim 21, Zaizen teaches the method of claim 11 as stated above. Zaizen teaches that “a soaking temperature after being heated by the radiation heating falls in a range of 900°C to 1100°C” (paragraph [0070]). Zaizen teaches that “a soaking time is preferable to be a range of 1-60 seconds” (paragraph [0070]). It has been held that obviousness exists where the claimed ranges overlap or lie inside ranges disclosed by the prior art. 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). Here, the claimed range of at least 5 second overlaps the range disclosed by the prior art of 1-60 seconds. Accordingly, the prior art renders the claim obvious.
Regarding claim 22, Zaizen teaches the method of claim 21 as stated above. Zaizen teaches that “the upper limit of an achieving temperature by the induction heating (end temperature) is desirable to be not higher than 780°C from a viewpoint of reducing the equipment cost” (paragraph [0064]). Zaizen teaches that “a soaking temperature after being heated by the radiation heating falls in a range of 900°C to 1100°C” (paragraph [0070]). Accordingly the steel sheet will heat from 780°C to a first step at a temperature in the range of 820°C to 880 °C and progress to a soaking temperature in a range of 900°C to 1100°C”, which reads on a second step at a temperature in the range of 900°C to 1150 °C (overlapping ranges).
Claims 17-18 are rejected under 35 U.S.C. 103 as being unpatentable over Zaizen et al. (EP 3378959 B1), as applied to claim 11 above, and further in view of Diplling et al. (EP 0572780 A2), as machine translated, previously cited.
Regarding claims 17-18, Zaizen teaches the method of claim 11 as stated above.
Zaizen is silent regarding wherein the first continuous furnace (3) is continuously flushed with a flushing gas and wherein the flushing gas has a hydrogen content of 20 to 50% by volume and flows in a counterflow direction opposite a movement of the electric strip.
Diplling is similarly concerned with heating of the strip in continuous annealing lines (paragraph [0001]). Diplling teaches that “cold-rolled sheet usually has a very thin, greasy coating of about 0.1 to 1 µm thickness consisting of residues of the rolling emulsion or rolling oil, mixed with a small proportion of iron abrasion in a coating density between 5 and 50 mg Fe per m² surface, and other solids - predominantly iron oxides, but also oxides of the alloying elements” (paragraph [0002]). Diplling teaches that “continuous annealing lines necessarily require strip cleaning systems upstream to remove oily residues from the strip surface” (paragraph [0008]). Diplling teaches that “it is the object of the invention to provide a cleaning process which takes into account the special conditions of the continuous annealing of metal strip, with which oily deposits on the strip surface can be removed reliably within the time period available due to the process, i.e. within a few seconds, without the use of organic and inorganic solvents and without disturbing side effects such as carbon deposits in the furnace chamber and carburization or oxidation of the annealed material” (paragraph [0031]). Diplling teaches that “dry protective gas, for example a hydrogen/nitrogen mixture in a ratio of four to one, flows in countercurrent through the outlet lock 3 into the cleaning section 4” (which reads upon “wherein the first continuous furnace (3) is continuously flushed with a flushing gas and wherein the flushing gas has a hydrogen content of 20 to 50% by volume and flows in a counterflow direction opposite a movement of the electric strip”, as recited in the instant claim; paragraph [0050]).
Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Zaizen to add cleaning with a dry protective gas, as taught by Diplling such that oily deposits on the strip surface can be removed reliably within the time period available due to the process, i.e. within a few seconds, without the use of organic and inorganic solvents and without disturbing side effects such as carbon deposits in the furnace chamber and carburization or oxidation of the annealed material.
Claim 19 is rejected under 35 U.S.C. 103 as being unpatentable over Zaizen et al. (EP 3378959 B1), as applied to claim 11 above, and further in view of Takagi et al. (US 20130071687 A1), previously cited.
Regarding claim 19, Zaizen teaches the method of claim 11 as stated above. Zaizen teaches that “it is effective to perform the heating in the finish annealing in two stages” (paragraph [0012]).
Zaizen is silent regarding heating the electric strip (2) initially in a first stage (6) to a temperature in the range of 680 °C- 700 °C and then in a second stage (7) to a temperature in the range of 700 °C - 950 °C.
Takagi is similarly concerned with subjecting the cold-rolled steel sheet to annealing including two-stage temperature raising processes (paragraph [0021]). Takagi teaches that “prior to subjecting the steel sheet to a galvanizing process, the steel sheet is subjected to annealing that undergoes two-stage temperature raising processes” (paragraph [0064]). Takagi teaches that “the annealing temperature is therefore 730 to 900° C., preferably 750 to 850° C” (which reads upon “and then in a second stage (7) to a temperature in the range of 700 °C - 950 °C”, as recited in the instant claim; paragraph [0089]). Takagi teaches that “the intermediate temperature is preferably to be a temperature lower than annealing temperature by about 200° C” (which reads upon “heating the electric strip (2) initially in a first stage (6) to a temperature in the range of 680 °C- 700 °C”, as recited in the instant claim; paragraph [0078]; 730 to 900° C - about 200° C = about 530 – 700° C). Takagi teaches that “structures of the surface layer portion and the inner layer portion of the steel sheet are controlled, respectively, by this annealing including two-stage temperature raising processes” (paragraph [0064]).
Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the annealing step of Zaizen to use a two-stage temperature raising processes, with an intermediate temperature of 530 – 700 ° C and an annealing temperature of 730 – 900 ° C, as taught by Takagi to control structures of the surface layer portion and the inner layer portion of the steel sheet.
It has been held that obviousness exists where the claimed ranges overlap or lie inside ranges disclosed by the prior art. 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). Here, the claimed range of 680 – 700 ° C lies inside the range disclosed by the prior art of 530 – 700 ° C. The claimed range of 700-950 °C overlaps the range disclosed by the prior art of 730 – 900 ° C. Accordingly, the prior art renders the claim obvious.
Claim 20 is rejected under 35 U.S.C. 103 as being unpatentable over Zaizen et al. (EP 3378959 B1) and Takagi et al. (US 20130071687 A1), as applied to claim 19 above, and further in view of Hou et al. (CN 104775021 A), as machine translated, previously cited.
Regarding claim 20, modified Zaizen teaches the method of claim 19 as stated above.
Zaizen is silent regarding the types of field inductors of the induction heating. A patent need not teach, and preferably omits, what is well known in the art. See MPEP § 2164.01. Longitudinal field inductors and transverse field inductor are known in the art.
Hou is similarly concerned with the field of steel plate heating in a continuous annealing process (paragraph [0002]). Hou teaches that “the technical problem to be solved by the present invention is to provide a rapid heating method and device for a continuous annealing production line of carbon steel thin plates, which fully utilizes the respective advantages of the three heating methods, solves the defects that longitudinal magnetic heating alone cannot heat to a temperature above the Curie point and that conventional heat exchange heating has a slow heating rate, and can ensure the uniformity of the strip temperature, thereby meeting the requirements of heating speed and economy to the greatest extent” (paragraph [0008]). Hou teaches that “the second stage is heated from the intermediate temperature to 10 to 50°C below the Curie point temperature using longitudinal magnetic induction heating” (which reads upon “wherein heating the electric strip (2) in the first stage (6) is performed by a longitudinal field inductor”, as recited in the instant claim; paragraph [0009]). Hou teaches that “the third stage is heated using transverse magnetic induction heating until the target temperature is reached” (which reads upon “wherein heating the electric strip (2) in the second stage (7) is performed by a transverse field inductor”, as recited in the instant claim; paragraph [0009]).
Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to perform the method of modified Zaizen initially using longitudinal magnetic induction heating, followed by a next stage using transverse magnetic induction heating, as taught by Hou to provide a rapid heating method for a continuous annealing production line of carbon steel thin plates, which fully utilizes the respective advantages of the three heating methods, solves the defects that longitudinal magnetic heating alone cannot heat to a temperature above the Curie point and that conventional heat exchange heating has a slow heating rate, and can ensure the uniformity of the strip temperature, thereby meeting the requirements of heating speed and economy to the greatest extent.
Response to Arguments
Applicant's arguments filed 1/16/26 have been fully considered but they are not persuasive. Applicant argues that Claim 11 has been amended to specify not only the temperature range ("at least 300 °C but also the technical effect achieved by the lower threshold of at least 300 °C in combination with the recited heating rate of at most 60 K/s-namely, "thereby evaporating fluids present on the strip, preventing condensation of residues, and producing a residue-free electric strip (remarks, page 4). Applicant argues that Zaizen et al. do not teach or suggest producing a residue-free electric strip prior to the strip entering the induction furnace (remarks, page 4). This is not found convincing because thereby evaporating fluids present on the strip, preventing condensation of residues, and producing a residue-free electric strip is a result of the claimed method steps, rather than a separate method step. Modified Zaizen teaches the claimed method steps, as stated above, accordingly, the claimed lack of residue would result from the claimed method steps, whether Zaizen mentions this result or not.
Applicant argues that while Zaizen et al. disclose a numerical upper limit of 500 °C for a preheating step, that temperature limit is expressly based on a completely different technical consideration and effect (remarks, pages 4-5). Applicant argues that Zaizen et al. are concerned with avoiding metallurgical recovery phenomena during preheating in a cost- reduction context, not with evaporation of fluids, prevention of residue condensation, or delivery of a residue-free strip to downstream processing (remarks, page 5). In response to applicant's argument that Zaizen is not concerned with preventing residue, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985).
Applicant argues that the apparent numerical overlap between Applicant's claimed lower threshold ("at least 300 °C") and Zaizen et al.'s upper limit ("not higher than 500 °C") is legally and technically insignificant, because the two ranges are motivated by, and optimized for, entirely different effects (remarks, page 5). Applicant argues that Zaizen et al. neither recognize the problem addressed by Applicant namely, contamination by residues entering the induction furnace-nor suggest that preheating should be controlled to achieve a residue-free electric strip prior to two-stage annealing (remarks, page 5). In response to applicant's argument that Zaizen is not concerned with preventing residue, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985).
Applicant argues that this unexpected result establishes the criticality of the claimed temperature and heating rate parameters (remarks, page 5). Applicant argues that as explained in In re Woodruff, where claimed subject matter differs from the prior art by a numerical range, patentability is established when the applicant demonstrates that the claimed range achieves unexpected results relative to the prior art range (remarks, page 5). Applicant further argues that here, Zaizen et al. did not recognize any need to initially heat the electric strip to produce a residue-free electric strip at all; rather, they merely suggest dividing induction heating into plural segments for equipment cost reasons and limiting preheating temperature to avoid metallurgical recovery (remarks, page 5). This is not found convincing because attorney statements regarding unexpected results, commercial success, long-felt need, inoperability of the prior art, skepticism of experts, and copying are not evidence without the support of objective evidence or a supporting declaration. The arguments of counsel cannot take the place of evidence in the record. In re Schulze, 346 F.2d 600, 602, 145 USPQ 716, 718 (CCPA 1965); In re Geisler, 116 F.3d 1465, 43 USPQ2d 1362 (Fed. Cir. 1997). See MPEP 716.01(c). It is not unexpected that volatile compounds would evaporate when heated.
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.
Contact Information
Any inquiry concerning this communication or earlier communications from the examiner should be directed to REBECCA JANSSEN whose telephone number is (571)272-5434. The examiner can normally be reached on Mon-Thurs 10-7 and alternating Fri 10-6.
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/REBECCA JANSSEN/Primary Examiner, Art Unit 1733
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