DETAILED ACTION
Claim Objections
Claims 2-16 are objected to because of the following informalities: In line 1 of each claim, please insert “fluoropolymer composition” between “The” and “production” so that all claims recite the same preamble. Appropriate corrections are required.
Claim Rejections - 35 USC § 103
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.
Claims 1, 2, 5-7, 9-11, and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Yamanaka et al. (US 10,047,175).
Example 1 of Yamanaka et al. discloses polymerizing tetrafluoroethylene in the presence of ammonium perfluorooctanoate surfactant and an initiator in a reactor at 55 ºC and 0.80 MPa to form an aqueous dispersion of polytetrafluoroethylene (PTFE). At the end of polymerization, the pressure was released to ordinary pressure (0.1 MPa) a gas phase in the reactor was replaced with nitrogen. The aqueous dispersion was treated further with nonionic surfactant and concentrated to a solid content of 60 % by being held at ordinary pressure and 65 ºC to cause water to evaporate off (col. 16, lines 34-38). After concentration, the aqueous dispersion is coagulated, filtered, washed and dried, and a PTFE powder is obtained. Yamanaka et al. is silent with respect to the time required to achieve concentration, but one of ordinary skill in the art would have found it obvious that the process is at least 15 minutes as claimed, especially since reduction in volume of 3.3 L of aqueous dispersion is carried out at ordinary pressure without stirring. Since the PTO cannot perform experiments, the burden is shifted to the Applicants to establish an unobviousness difference. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). See MPEP § 2112-2112.02.
Claims 1, 2, 5-7, 9, 11, and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Ji et al. (CN 104403036) in view of Yamanaka et al. (US 10,047,175).
Ji et al. teaches preparation of a fluoropolymer dispersion and a step of concentrating the fluoropolymer dispersion to increase the solid content and to reduce the content of fluorinated surfactant. In Example 1, an aqueous dispersion of polytetrafluoroethylene (PTFE) is prepared by polymerizing tetrafluoroethylene in the presence of EEA (perfluoro(2-ethoxy-2-fluoroethoxy)acetic acid) fluorinated surfactant and initiator at a temperature of 80 ºC to 100 ºC and pressure of 2.8 MPa. In the concentration step, the aqueous dispersion of PTFE is heated to 50 ºC and allowed to stand at 55 ºC for 10 hours to obtain a 60-70 % PTFE dispersion. Ji et al. does not disclose details regarding termination of polymerization. Yamanaka et al. teaches that polymerization of tetrafluoroethylene is terminated by reducing the pressure in the reactor to ordinary pressure (0.1 MPa) and purging the reactor with an inert gas such as nitrogen. One of ordinary skill in the art, carrying out the invention of Ji et al., would have found it obvious to terminate the reaction by the process disclosed in Yamanaka et al., and since the termination procedure is well established in the art, one of ordinary skill in the art would have expected the combination of teachings to work with a reasonable expectation of success.
Claims 3, 4, 8, and 12-15 are objected to as being dependent upon a rejected base claim but would be allowable if rewritten to overcome claim objections, supra, and if rewritten in independent form including all the limitations of the base claim and any intervening claims. Yamanaka et al. does not teach or suggest reducing the pressure in a reactor below 0.00 MPaG prior to feeding inert gas into the reactor. Prior art does not teach adding a radical generator to an aqueous dispersion and subjecting the aqueous dispersion to heat treatment. Finally, prior art does not disclose an aqueous dispersion comprising a water-soluble fluorine-containing compound such that a fluoropolymer composition is obtained having a reduced content of said water-soluble fluorine-containing compound upon heat treatment.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Rip A. Lee whose telephone number is (571)272-1104. The examiner can be reached on Monday through Friday from 9:00 AM - 5:00 PM. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Robert Jones, can be reached at (571)270-7733. The fax phone number for the organization where this application or proceeding is assigned is (571)273-8300.
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/RIP A LEE/Primary Examiner, Art Unit 1762 February 12, 2026
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