DETAILED ACTION
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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 21 January 2026 has been entered.
Response to Arguments
Applicant's arguments filed 21 January 2026 have been fully considered but they are not persuasive. The associated arguments are addressed below:
Applicant argues that modifying Hyuck by incorporating the teachings of Weetman would not be obvious because their fundamental operating principles are distinct. Examiner reminds Applicant that 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). Further, modifying the blade angle of Hyuck with the blade angle taught by Weetman would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention because doing so would enable the blades to scoop or lift the liquid upward, enabling gas and air to mix with the liquid (see Weetman [0030]).
Applicant argues that Weetman does not disclose the position of the uppermost impeller. However, Examiner relied upon Hyuck to reject this limitation. Applicant also argues that the angle of the blades in Weetman differ from the blade angle of the present invention. Examiner reminds Applicant that the range disclosed by Weetman overlaps with the claimed range, and therefore a prima facie case of obviousness exists (see MPEP 2144.05.I).
Applicant argues that Teruo represents a technical field distinct from that of the present invention. Examiner disagrees as Teruo, Hyuck, and the present invention are related to stirring devices for polymerization.
Applicant argues that the (H/D) ratio disclosed by Teruo results in different effects from those of the present invention. Examiner reminds applicant that the range disclosed by Teruo overlaps with the claimed range, and therefore a prima facie case of obviousness exists (see MPEP 2144.05.I). Further, 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 Teruo does not disclose the claimed angle of the stirring blades. However, Teruo was not relied upon for rejecting the limitation of blade angle.
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.
Claims 1-12 are rejected under 35 U.S.C. 103 as being unpatentable over Hyuck (KR-20160004074-A) in view of Weetman (US-20040217492-A1) and Teruo (JP-2001179069-A).
Regarding Claim 1, Hyuck discloses a batch (added as an antifoaming agent in batches; see [0072]) suspension polymerization (see [0037]) reactor for preparing a vinyl chloride resin (stirred tank reactor and a method for producing PVC resin; see [0002]), the reactor comprising: a paddle type agitator (see [0019]) having two or more stages of impellers (see [0014]) wherein a top impeller of the agitator is disposed in a lower portion of a liquid interface inside the reactor (see Fig. 1, Part 13).
Hyuck does not explicitly teach the angle of the impeller blades. However, Weetman discloses an angle of blades of an impeller being 5 to 20o with respect to an agitator shaft (said first blade having a first portion oriented at a first angle to the radial axis; see claim 20 and wherein said first angle between approximately 0 degree to approximately 15 degree; see claim 21) and an angle of blades of the other lower impellers except the top impeller is 0 with respect to the agitator shaft in a vertical direction (said first blade having a first portion oriented at a first angle to the radial axis; see claim 20 and wherein said first angle between approximately 0 degree to approximately 15 degree; see claim 21).
Hyuck and Weetman are both considered analogous to the claimed invention because they are in the same field of impellers. Hyuck discloses that adjusting the angle of the impeller within the reactor can obtain a homogenized particle state for each reaction, thereby obtaining a product with an optimal particle size distribution and particle shape (see [0003]). There are a finite number of known ways to implement an angle. Therefore, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to have modified Hyuck by trying the impellers taught by Weetman as there was a reasonable expectation of success.
The combination of Hyuck and Weetman does not explicitly teach the claimed ratio of t/D. However, Teruo discloses a relationship between a distance (t) between an upper portion of blades of the top impeller and the liquid interface inside the reactor and a reactor diameter (D) which is t/D = 0.22 to 0.3 (stirring blade that is mounted on the stirring rotation shaft, and is the maximum from the liquid surface with respect to the inner diameter (D) of the stirring tank. The ratio (H/D) of the depth (H) to the upper end of the upper stirring blade is 0.25 to 0.45; see [0006]).
Hyuck and Teruo are both considered analogous to the claimed invention because they are in the same field of stirring apparatuses for polymers. Therefore, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to have modified Hyuck by incorporating the teachings of Teruo and providing the forementioned ratio. Doing so provides a stirring device which is less likely to cause crumbs to adhere as scales or block the pipes (see Teruo [0004] - [0006]).
Regarding Claim 2, Hyuck, Weetman, and Teruo together disclose the batch suspension polymerization reactor for preparing vinyl chloride resin of claim 1. Hyuck further discloses the reactor comprising a reflux condenser (see [0010]).
Regarding Claim 3, this claim further specifies the angle of the blades mentioned in claim 1. Please refer to the claim 1 rejection, as the claim 3 limitation of “15 to 20o” is included in the referenced art and the claim 3 rejection follows the same logic as the associated limitation of claim 1.
Regarding Claim 4, Hyuck, Weetman, and Teruo together disclose the batch suspension polymerization reactor for preparing vinyl chloride resin of claim 1. Hyuck further discloses improved heat removal of a reflux condenser, but does not explicitly teach a comparative ratio of efficiency. However, the limitation claiming, “the polymerization reactor has a relative heat removal ratio of a reflux condenser having an efficiency of twice or more the efficiency when the angle of the blades of the top impeller is 0°” is claiming that the efficiency is increased as a consequence of adjusting the angle of the top impeller blades, but the efficiency is not a structural limitation. Therefore, because the prior art teaches the structural limitation of the blade angle, as mentioned in the claim 1 rejection, then it naturally follows that it will exhibit the same increase in efficiency.
Regarding Claim 5, this claim further specifies the angle of the blades mentioned in claim 1. Please refer to the claim 1 rejection, as the claim 5 limitation of “5 to 15o” is included in the referenced art and the claim 5 rejection follows the same logic as the associated limitation of claim 1.
Regarding Claim 6, Hyuck discloses a batch (see [0072]) suspension polymerization method for preparing a vinyl chloride resin (see [0037]), the method comprising performing a reaction by adding a monomer (including a step of polymerizing a vinyl chloride monomer using the stirred tank reactor; see [0012]). The remaining limitations of claim 6 are identical to the structural limitations of claim 1. Please see the claim 1 rejection as the rejection of the structural limitations of claim 6 follow the same logic as that of claim 1.
Regarding Claim 7, Hyuck, Weetman, and Teruo together disclose the batch suspension polymerization method for preparing a vinyl chloride resin of claim 6. Hyuck further teaches in the polymerization reactor, heat is removed in a reflux condenser and is circulated to the reactor (reflux condenser repeatedly condenses the solvent vaporized during the reaction and returns it back to the bottom of the reactor, thereby efficiently controlling the heat generated during polymerization; see [0024]).
Regarding Claim 8, Hyuck, Weetman, and Teruo together disclose the batch suspension polymerization method for preparing a vinyl chloride resin of claim 6. This claim further specifies the angle of the blades mentioned in claim 1 and claim 6. Please refer to the claim 1 rejection, as the claim 8 limitation of “15 to 20o” is included in the referenced art and the claim 8 rejection follows the same logic as the associated limitation of claim 1.
Regarding Claim 9, Hyuck, Weetman, and Teruo together disclose the batch suspension polymerization method for preparing a vinyl chloride resin of claim 6. This claim further specifies the angle of the blades mentioned in claim 1 and claim 6. Please refer to the claim 1 rejection, as the claim 9 limitation of “5 to 15o” is included in the referenced art and the claim 9 rejection follows the same logic as the associated limitation of claim 1.
Regarding Claim 10, Hyuck discloses an agitator (impeller; see [0003]) for batch (added as an antifoaming agent in batches; see [0072]) suspension polymerization (see [0037]) for preparing a vinyl chloride resin (see [0003]), the agitator comprising: a jacket (see [0025]), a baffle (see [0025]), and a reflux condenser (see [0025]). The remaining limitations of claim 10 are identical to the structural limitations of claim 1. Please see the claim 1 rejection as the rejection of the remaining structural limitations of claim 10 follow the same logic as that of claim 1.
Regarding Claim 11, Hyuck, Weetman, and Teruo together disclose the agitator for batch suspension polymerization for preparing a vinyl chloride resin of claim 10. This claim further specifies the angle of the blades mentioned in claim 1 and claim 10. Please refer to the claim 1 rejection, as the claim 11 limitation of “15 to 20o” is included in the referenced art and the claim 11 rejection follows the same logic as the associated limitation of claim 1.
Regarding Claim 12, Hyuck, Weetman, and Teruo together disclose the agitator for batch suspension polymerization for preparing a vinyl chloride resin of claim 10. This claim further specifies the angle of the blades mentioned in claim 1 and claim 10. Please refer to the claim 1 rejection, as the claim 12 limitation of “5 to 15o” is included in the referenced art and the claim 12 rejection follows the same logic as the associated limitation of claim 1.
Conclusion
All claims are identical to or patentably indistinct from, or have unity of invention with claims in the application prior to the entry of the submission under 37 CFR 1.114 (that is, restriction (including a lack of unity of invention) would not be proper) and all claims could have been finally rejected on the grounds and art of record in the next Office action if they had been entered in the application prior to entry under 37 CFR 1.114. Accordingly, THIS ACTION IS MADE FINAL even though it is a first action after the filing of a request for continued examination and the submission under 37 CFR 1.114. See MPEP § 706.07(b). 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 ALYSSA LEE KUYKENDALL whose telephone number is (571)270-3806. The examiner can normally be reached Monday- Friday 9:00am-5:00pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Claire Wang can be reached at 517-270-1051. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/A.L.K./Examiner, Art Unit 1774
/CLAIRE X WANG/Supervisory Patent Examiner, Art Unit 1774