Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendment
This action is responsive to applicant’s amendment filed 6/11/2025.
Claims 1 and 6-9 are pending.
The previous rejection of claims 1, 6-8 under 35 U.S.C. 103 as being unpatentable over Ito et al. (JP 2007262567) further in view of Sakai et al (US2017/0050873) is maintained in view of applicant’s amendment.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action.
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, 6-8, and 9 are rejected under 35 U.S.C. 103 as being unpatentable over Ito et al. (JP 2007262567) further in view of Sakai et al (US2017/0050873).
Regarding claims 1 and 7, Ito discloses a method for inhibiting corrosion of an evaporation tube in a boiler (para 0008, 0014, 0042), comprising subjecting a feed-water which ion-exchanged water for the boiler (para 0008, 0016 and 0042), the feed-water has a dissolved oxygen concentration of water in the boiler of 1.0 mg/L or less (para 0042), adding a scale inhibitor (alkoxyalkylamine having 3 to 5 carbon atoms and (B) morpholine) having a concentration of the scale inhibitor in the water in the boiler is 1 to 1,000 mg/L (para 0039 and 0042) to the water in the boiler (para 0013 and 0042. Ito does not specifically disclose subjecting a feed water for the boiler to a degassing treatment with a degasser to control the dissolved oxygen concentration. Ito, however, discloses the boiler’s feedwater system includes deaerator, which is used to reduce to dissolved oxygen concentration (para 0014, 0028). Therefore, it would have been obvious to one of ordinary skill in the art before the filling date of the invention to carry out the method of Ito to include a step of subjecting the feed water for the boiler to a degassing treatment with a deaerator, thereby reducing the dissolved oxygen concentration of the water in the boiler to 1.0 mg/L or less in order to prevent corrosion due to oxygen, prior to adding the scale inhibitor. Ito does not disclose the scale inhibitor comprises at least one poly(meth)acrylic acid compound selected from the group consisting of polyacrylic acid having a weight-average molecular weight of 50,000 to 120,000 and a salt of the polyacrylic acid, and polymethacrylic acid having a weight-average molecular weight of 5,000 to 10,000 and a salt of the polymethacrylic acid. Sakai discloses a method for removing scale deposited in a system of a steam generating facility, wherein polyacrylic acid having a weight-average molecular weight of more than 50,000 and 120,000 or less and/or a salt thereof (para 0043, 0045) is added to feed water of the steam generating facility. When the feed water contains iron, polymethacrylic acid having a weight-average molecular weight of more than 5,000 and 60,000 or less and/or a salt thereof (para 0055, 0057) is further added in combination (abstract). Sakai further discloses the polyacrylic acid and/or the salt of the polyacrylic acid is added so that a concentration of the polyacrylic acid and/or the salt of the polyacrylic acid in water of a steam generating unit in the steam generating facility is 1 to 1,000 mg/L (para 0023) and the polymethacrylic acid and/or the salt of the polymethacrylic acid is added so that a concentration of the polymethacrylic acid and/or the salt of the polymethacrylic acid in the water of the steam generating unit in the steam generating facility is 1 to 1,000 mg/L (para 0025). Therefore, it would have been obvious to one of ordinary skill in the art before the filling date of the invention to using polyacrylic acid and/or the salt thereof and the polymethacrylic acid and/or the salt thereof in addition to the scale inhibitor in the method of Ito, so that scale deposited in a system can be efficiently removed during the operation of a steam generating facility without corrosion of the system by using a chemical in a relatively small amount without using a chelating agent. Furthermore, a high scale removing effect can be provided, even when iron is present in feed water in a high concentration (Sakai, para 0029). The limitation “the dissolved oxygen concentration of water, measured immediately after an outlet of the degasser and before the boiler is controlled to 1.0mg/L or less” does not require that “the dissolved oxygen concentration of water, measured immediately after an outlet of the degasser and before the boiler” is 1.0mg/L or less but rather that the dissolved oxygen concentration to be controlled (or adjusted) to 1.0mg/L or less. Ito does not specifically the dissolved oxygen concentration of water, measured immediately after an outlet of the degasser is controlled to 1.0mg/L or less. Ito, however, discloses the dissolved oxygen concentration in the feed water is preferably reduced to 200 μg/L or less, more preferably 30 μg/L or less, and even more preferably 7 μg/L or less (the dissolved oxygen concentration in the make-up water was 0.007 mg/L, para 0042) using a deaerator or the like. It is preferable to add an oxygen scavenger in order to remove dissolved oxygen that could not be removed by the deoxygenation treatment using a deaerator (para 0028 and 0042). Ito’s disclosure provides a motivation for controlling the dissolved oxygen concentration, measured immediately after an outlet of the degasser and before the boiler, is to 200 μg/L or less, more preferably 30 μg/L or less, and even more preferably 7 μg/L or less (which includes 1.0mg/L or less).
Regarding claims 6 and 8, Ito discloses the boiler is a once-through boiler (para 0015). Ito also disclose that there is no particular limitation on the type of boiler that can be used (para 0015). Therefore, it would have been obvious to one of ordinary skill the art before the filling date of the invention to use the corrosion inhibition method of Ito in view of Sakai in a small-type rectangular once-through boiler system, with a reasonable expectation of success for effectively prevent corrosion of steel and copper alloys in the boiler system.
Regarding claim 9, Ito discloses the scale inhibitor is added to the feed water of the boiler (para 0023 and 0042), it would have reasonably suggested to one having ordinary skill the art that the scale inhibitor would be added to into the feed water downstream of the degasser before of the boiler.
Response to Arguments
Applicant’s arguments filed 6/11/2025 with respect to references Ito 567 and Sakai have been considered but they are not persuasive.
Applicant argues that Ito teaches the use of a deaerator to reduce the dissolved oxygen in the feed water but fails to disclose or suggest measuring the dissolved oxygen concentration of the claimed location of the feed-water which is immediately after an outlet of the degasser and before the boiler, and fails to disclose or suggest controlling the dissolved oxygen concentration to 1.0 mg/L or less before adding the claimed scale dispersant. The “0.007 mg/L” stated in paragraph [0042] of Ito refers to the dissolved oxygen concentration of the boiler feed water initially introduced into the boiler, and is not the consequence concentration intentionally controlled by the deaerator.
The examiner respectfully disagrees with applicant’s argument.
The limitation “the dissolved oxygen concentration of water, measured immediately after an outlet of the degasser and before the boiler is controlled to 1.0mg/L or less” does not require that “the dissolved oxygen concentration of water, measured immediately after an outlet of the degasser and before the boiler” is 1.0mg/L or less but rather that the dissolved oxygen concentration to be controlled (or adjusted) to 1.0mg/L or less. Ito does not specifically the dissolved oxygen concentration of water, measured immediately after an outlet of the degasser is controlled to 1.0mg/L or less. Ito, however, discloses in order to prevent corrosion due to oxygen, the dissolved oxygen concentration in the feed water is preferably reduced to 200 μg/L or less, more preferably 30 μg/L or less, and even more preferably 7 μg/L or less using a deaerator or the like (para 0028). Given that a deaerator is a device that is used for the removal of dissolved gases like oxygen from a liquid, one of ordinary skill in the art after reading Ito’s disclosure would have expected that the dissolved oxygen concentration in the feed water coming out of the degasser to be 7 μg/L.
In addition, Ito discloses that it is preferable to add an oxygen scavenger in order to remove dissolved oxygen that could not be removed by the deoxygenation treatment using a deaerator (para 0028 and 0042). Ito further discloses that the corrosion inhibition method of the present invention can also be used in combination with a method of suppressing corrosion of a boiler system by adding oxygen or hydrogen peroxide instead of adding an oxygen scavenger to maintain the dissolved oxygen concentration at 20 to 200 μg/L and forming a protective film made of hematite on the steel surface (so-called oxygen treatment). Ito’s disclosure clearly provides a motivation for controlling and maintaining the dissolved oxygen concentration in the feed water to 200 μg/L or less, more preferably 30 μg/L or less, and even more preferably 7 μg/L or less (which includes 1.0mg/L or less), before the boiler, to inhibit corrosion of metals in contact with water in a boiler system.
Applicant further argues that Ito fails to disclose or suggest controlling the dissolved oxygen concentration to 1.0 mg/L or less before adding the claimed scale dispersant. However, it is clear that Ito discloses the dissolved oxygen concentration is 1.0 mg/L or less before adding the scale dispersant (para 0042- the dissolved oxygen concentration in the make-up water was 0.007 mg/L. A composition containing 70% by weight of 3-methoxypropylamine and 30% by weight of morpholine was added to the make-up water in an amount of 2.4 mg/L).
Applicant also argued that Ito discloses reducing dissolved oxygen to below 200 ug/L, but fails to establish a precise sequence and positional relationship with the subsequent dispersant addition step. However, the law held that the transitional term “comprising”, which is synonymous with "including," "containing," or "characterized by," is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. See, e.g., Mars Inc. v. H.J. Heinz Co., 377 F.3d 1369, 1376, 71 USPQ2d 1837, 1843 (Fed. Cir. 2004). The law also held that selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results. See In re Burhans, 154 F.2d 690, 69 USPQ 330 (CCPA 1946), In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930), and Ex parte Rubin, 128 USPQ 440 (Bd. App. 1959).
Applicant argued that Sakai is aim for removing scale deposited inside the boiler and teaches PAA/salts of a relevant molecular weight range and PMAA/salts of a wider range, the purpose of Sakai is to remove scale at immediate use (short-term use), which is also quite different from the technical problem of “corrosion fatigue” (long-term use) and therefore the amended claim 1 of present application cannot be arrived based on Ito in view of Sakai. The examiner respectfully disagrees. Sakai discloses that the weight-average molecular weight of the polyacrylic acid used in the present invention is more than 20,000 and 170,000 or less and preferably more than 50,000 and 120,000 or less. When the weight-average molecular weight of the polyacrylic acid is less than 20,000, the scale removing effect is not sufficiently produced. Similarly, when the weight-average molecular weight of the polyacrylic acid is more than 170,000, the scale removing effect decreases. In the case of the polyacrylic acid salt, it is sufficient that the weight-average molecular weight of polyacrylic acid serving as a base of the polyacrylic acid salt satisfies the above conditions. The polyacrylic acid (salt) is preferably added in such an amount that the concentration in the water of the steam generating unit in the steam generating facility, that is, the concentration in the boiler water is 1 to 1,000 mg/L, in particular, 10 to 500 mg/L. When the concentration of the polyacrylic acid (salt) in the boiler water is above the lower limit, the scale removing effect is easily produced. When the concentration is below the upper limit, the complication of a water discharge process due to an increase in COD is prevented, and good cost-effectiveness can be achieved (para 0043-0047). Sakai discloses that when the poly(meth)acrylic acid and their salts are used, the deposition of scale is prevented (long-term use) while at the same time a constant scale removing effect (short-term use) is maintained.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to HAIDUNG D NGUYEN whose telephone number is (571)270-5455. The examiner can normally be reached M-Th: 10a-3p.
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/HAIDUNG D NGUYEN/Primary Examiner, Art Unit 1761
9/20/2025