DETAILED ACTION
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 10 December 2025 has been entered.
Response to Amendment
Amendment to claim 1 and cancelation of claim 8 are noted.
Response to Arguments
Applicant's arguments filed 10 December 2025 have been fully considered but they are not persuasive.
Applicant argues that Krafft’s process is directed to a system in which hydrogen chloride is recovered and recycled back into the chlorination reaction as a reactant, whereas Asaoka’s system produces hydrogen chloride as an undesired by-product, which is designed to be removed and discarded, in the manufacture of para-dichlorobenzene. Therefore, it is Applicant’s position that the fundamental purpose and operating conditions are distinct and that the proposed modification would require substantial redesign of process flow, equipment configuration, and reaction control, would not have been routine substitution, and there would have not been a reasonable expectation of success in combining the two systems. Applicant further contends that the proposed combination is based on improper hindsight reconstruction.
This argument is not found persuasive. Applicant's conclusory statement that the combination would "require substantial redesign" and therefore "would not have been routine substitution" is insufficient to rebut the office's position taken in the previous action as it does not elaborate as to the underlying reasons why Applicant believes such substitution would not be routine. The office maintains that Asaoka, the primary reference, discloses removing hydrogen chloride from the final stage effluent, but does not specifically disclose that this is done by stripping (see Abstract; Fig. 1; p. 3, 7). Krafft, the modifying reference, discloses that stripping is a known technique for the purpose of separating hydrogen chloride from a chlorination reaction effluent (see [0158]). The office maintains that use of stripping to perform the separation in the Asaoka reference would have been obvious to a person of ordinary skill in the art and associated with a reasonable expectation of success. The proposed modification does not require the recycling features of Krafft, rather provides evidence that stripping is a known technique for removing hydrogen chloride from a reaction effluent.
The test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981).
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
Applicant argues that Asaoka employs cooling jackets installed around individual reactors for temperature control and nowhere discloses or suggests a heat exchanger positioned between reactors that cools a reaction product from a front-end reactor and injects the cooled product into the bottom of a rear-end reactor. Applicant contends that Asaoka’s condenser 12 serves to condense an evaporated component into a liquid and the condensation target is the cooling medium. In contrast, the heat exchanger in the present application functions to prevent the temperature of the reaction liquid from increasing during the exothermic chlorination reaction and the cooling described is performed within a range where chlorine is not liquefied, citing [0034]-[0035] of the instant specification.
This argument is not found persuasive. The office maintains the position that the condensers 12 of Asaoka teaches the heat exchanger feature as required by the instant claims. The function of condensing an evaporated component in the condensers requires heat exchange, i.e., cooling of the evaporated component into a liquid phase. Applicant relies on teachings in the specification with respect to heat exchange conditions which are not required by the claims. Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Furthermore, while Asaoka discloses the additional feature of cooling jackets on the reactors, this feature is not excluded from the instant claims. 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).
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 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Asaoka (WO 2010/110163) in view of Krafft et al (EP 1 760 060).
Asaoka is cited from the English machine translation, provided herewith.
Regarding claims 1 and 6, Asaoka is directed to a process for the preparation of chlorobenzene comprising subjecting a feed of benzene and/or monochlorobenzene to chlorination reactions carried out in a plurality of column reactors connected in series. Hydrogen chloride is produced as a by-product and may be removed from the final stage effluent (i.e., rearmost reactor) (see Abstract; Fig. 1; p. 3, 7).
Additionally, Asaoka discloses wherein a reaction product produced in a front end reactor is cooled by a heat exchanger positioned between the reactors and then a predetermined amount of the cooled reaction product is injected into the bottom of a rear end reactor (see Figs. 1, 2 & 11; pp. 6-7, 9).
Asaoka differs from the instant claimed invention in that the reference does not disclose wherein the hydrogen chloride is removed by heating in a stripping column.
Krafft is directed to a process for preparation of chlorinated hydrocarbons. After chlorination reaction, the effluent from the reactor is stripped with steam or nitrogen (i.e., heated) in a stripping column to remove hydrogen chloride from the product (see [0158]).
Krafft establishes that stripping is a known technique for the purpose of separating hydrogen chloride from a chlorination reaction effluent. Applying this known separation technique to the process of Asaoka as an alternate means of reaction effluent separation would have been obvious to a person of ordinary skill in the art and associated with a reasonable expectation of success.
While Krafft does not explicitly disclose the number of stages in the stripping column, a person of ordinary skill in the art would determine, by routine experimentation, the number of stages required to carry out sufficient separation of the hydrogen chloride from the reaction effluent. Absent a showing of criticality or unexpected results, the claimed number of stages is not considered to patentably distinguish the instant claims over the cited prior art.
Regarding claim 7, Asaoka discloses wherein the chlorination reaction is performed in each reactor by injecting an equal amount of chlorine gas into the bottom of each reactor, and hydrogen chloride gas generated in each reactor is partially discharged from each reactor (see Figs. 2 & 11; pp. 7-9).
Claims 2-5 are rejected under 35 U.S.C. 103 as being unpatentable over Asaoka in view of Krafft, as applied to claim 1, in further view of Dalary et al (US 2016/0347625).
Regarding claim 2, Krafft discloses wherein heating is performed by steam supplied to the stripping column, as discussed above, but does not provide the details of the stripping arrangement, as claimed, i.e., wherein steam is supplied from a reboiler connected to the bottom of the stripping column.
However, such arrangement is common-place in stripping columns, as shown in Dalary. Dalary discloses a stripper column operating with steam as the stripping medium, wherein steam is provided to the column by a reboiler connected to the bottom of the stripping column (see Fig. 1; [0046]; [0115]). In this regard, the office is of the position that adapting such arrangement would have been obvious to a person of ordinary skill in the art, given that it provides the stripping steam from a readily available source within the process.
Regarding claims 3-5, a person of ordinary skill in the art would readily determine, by routine experimentation, the pressure and temperature conditions, as well as the amount of steam supplied to the stripper, which effect maximum separation efficiency of hydrogen chloride in the stripping column. Therefore, absent a showing of criticality or unexpected results, the claimed temperature, pressure, steam amount, and HCl removal rate are not considered to patentably distinguish the instant claims over the cited prior art.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RENEE ROBINSON whose telephone number is (571)270-7371. The examiner can normally be reached Monday - Thursday 8:00a-5:00p and Friday 8:00a-2:00p.
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/Renee Robinson/Primary Examiner, Art Unit 1772