Prosecution Insights
Last updated: August 14, 2026
Application No. 18/644,454

HOLLOW POLYMER PARTICLES AND METHOD FOR MANUFACTURING SAME

Final Rejection §103§112
Filed
Apr 24, 2024
Priority
Sep 14, 2018 — JP 2018-172144 +2 more
Examiner
REDDY, KARUNA P
Art Unit
1764
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Sekisui Kasei Co. Ltd.
OA Round
2 (Final)
42%
Grant Probability
Moderate
3-4
OA Rounds
1y 2m
Est. Remaining
52%
With Interview

Examiner Intelligence

Grants 42% of resolved cases
42%
Career Allowance Rate
357 granted / 842 resolved
-22.6% vs TC avg
Moderate +10% lift
Without
With
+9.9%
Interview Lift
resolved cases with interview
Typical timeline
3y 6m
Avg Prosecution
66 currently pending
Career history
903
Total Applications
across all art units

Statute-Specific Performance

§101
0.6%
-39.4% vs TC avg
§103
52.7%
+12.7% vs TC avg
§102
12.8%
-27.2% vs TC avg
§112
24.2%
-15.8% vs TC avg
Black line = Tech Center average estimate • Based on career data from 842 resolved cases

Office Action

§103 §112
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 . Claims filed 4/24/2024 are made of record. Claims 1-10 are currently pending in the application. Claim Objections Claims 1-10 are objected to because of the following informalities: The text of present claims 1-10 is grainy and lacks clarity. Applicant is advised to provide claims with text that is clear. Appropriate correction and/or clarification are required. Claim Rejections - 35 USC § 112 The following is a quotation of 35 U.S.C. 112(b): (b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention. The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph: The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention. Claims 2-3 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. Claims 2 and 3 recite the limitation "the phosphate ester monomer" in line 2. There is insufficient antecedent basis for this limitation in the claim. Claim 3 recites “phosphate ester monomer unit is represented by the formula (1): PNG media_image1.png 78 399 media_image1.png Greyscale ”. However, PNG media_image2.png 72 215 media_image2.png Greyscale structure includes (R2-O)m and -(O-C) units which results in a peroxide. Additionally, PNG media_image3.png 72 268 media_image3.png Greyscale includes PNG media_image4.png 71 115 media_image4.png Greyscale and when x = 2, there are not enough PNG media_image4.png 71 115 media_image4.png Greyscale for bonding to the 2 chains. Hence, metes and bounds of present claims cannot be ascertained by one of ordinary skill in art prior to the filing of present application. However, for examination purposes, the phosphate ester monomer unit is interpreted as the species listed in originally filed disclosure (paragraph 0032). Claim Rejections - 35 USC § 103 In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status. 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 1-4 and 7-10 are rejected under 35 U.S.C. 103 as being unpatentable over Ishimori et al (US 2015/0004127 A1) in view of Ando et al (US 2017/0058116 A1). Regarding claim 1, Ishimori et al disclose porous resin particles (i.e., reads on hollow polymer particles in present claim 1) that comprise a polymer of monomer mixture including vinyl-based monomers (abstract) which reads on vinylic monomer unit in present claim 1. The volume average particle diameter of the porous resin particles is preferably from 4 microns to 40 microns (paragraph 0066) which overlaps with the volume average particle diameter in present claim 1. Case law holds that when the range of instant claims and that disclosed in prior art overlap, a prima facie case of obviousness exists. See In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976). See MPEP § 2144.05. Ishimori et al are silent with respect to phosphorus element content and alkaline earth metal content. However, Ishimori et al in the general disclosure teach that in suspension polymerization, the aqueous phase preferably contains a dispersion stabilizer to manufacture desired porous particles in a more stable manner. Of these dispersion stabilizers, the dispersion stabilizer is preferably magnesium pyrophosphate(paragraph 0082). See example 1, wherein the polymerization process includes magnesium pyrophosphate as a dispersion stabilizer (paragraph 0181). Hydrochloric acid was added until the slurry showed a pH of 2 or less to decompose magnesium pyrophosphate. The slurry was washed in water and dehydrated to obtain resin particles (paragraph 0184). The porous resin particles are filtered to remove aqueous medium (paragraph 0079). It is noted that magnesium pyrophosphate and HCl reaction products include hypophosphorus acid (H4P2O7) and 2MgCl2 (i.e., equal amounts of phosphorus and alkaline earth elements) and have a solubility of 1000g/L and 54 g/100mLm at 200C, respectively. Additionally, Ando et al teach a method of producing particles by suspension polymerization (abstract). Preferably, the monomer mixture contains at least one polymerizable phosphoric acid monomer. Addition of polymerizable phosphoric acid monomer to the monomer mixture can improve stability of the droplets of monomer mixture in the aqueous medium when the monomer mixture is subjected to the aqueous suspension polymerization (paragraph 0041). The polymerizable phosphoric acid monomer preferably falls within the range from 0.01 to 0.8 parts by weight. If the amount exceeds 1 part by weight relative to 100 parts by weight of polymerizable vinyl monomer, particles are likely to include fine particles whose size is too small (paragraph 0046). Therefore, in light of the teachings in Ando et al and general disclosure of Ishimori et al, it would have been obvious to one skilled in art prior to the filing of present application to wash the slurry after decomposing magnesium pyrophosphate, to include any amount of alkaline earth metal element (i.e., magnesium) including 1 to 100 mg/kg and include small amounts of polymerizable phosphoric acid monomer (such as 0.01 to 0.8 parts), to obtain hollow polymer particles having phosphorus element content of 1 to 200 mg/kg and alkaline earth metal content of 1 to 100 mg/Kg with higher amounts of phosphorus than the alkaline earth metal content, for above mentioned advantages, and absent evidence to the contrary. Regarding claims 2 and 3, examples of polymerizable phosphoric acid monomer, in Ando et al, include PNG media_image5.png 94 400 media_image5.png Greyscale wherein n represents 1 to 5, when a = 1, b = 2 and when a = 2, b = 1 (paragraph 0041) which reads on phosphate ester monomer in present claim 2; and phosphate ester monomer of present claim 3, wherein R1 = methacrylic group, R2O = C2H4O, v = 1 to 5, x = 1 or 2. Regarding claim 4, Ishimori et al teach that porous resin particles have a specific surface area of 3 m2/g to 200 m2/g (paragraph 0064) which overlaps with the specific surface area in present claim 4. Case law holds that when the range of instant claims and that disclosed in prior art overlap, a prima facie case of obviousness exists. See In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976). See MPEP § 2144.05. The volume average particle diameter of the porous resin particles is preferably from 4 microns to 40 microns (paragraph 0066). Therefore, given the porous resin particles, of Ishimori et al have volume average particle diameter and specific surface area in overlapping ranges, one skilled in art prior to the filing of present application would have a reasonable basis to expect the bulk specific graving to overlap with the bulk specific gravity of 0.1 to 0.4 g/cm3, absent evidence to the contrary. Since PTO cannot conduct experiments, the burden of proof is shifted to the applicants to establish an unobviousness difference, see In re Best, 562 F.2d 1252, 195 USPQ 430 (CCPA 1977). Regarding claim 7, Ishimori et al teach that light diffusion member may be prepared by dispersing the porous resin particles as a light diffusing agent in a transparent base material resin (paragraph 0125) which reads on resin composition comprising the hollow polymer particles in present claim 7. Regarding claim 8 and 10, Ishimori et al teach that light diffusion coating film may be prepared by coating a transparent base material with a light diffusing coating material (paragraph 0123) which reads on coating composition in present claim 8 and light diffusion film in present claim 10. Regarding claim 9, Ishimori et al teach that external preparation, such as cosmetic material, in which the porous resin particles are blended exhibits improved spreading and slippage (paragraph 0067). Claims 1-4 and 7-10 are rejected under 35 U.S.C. 103 as being unpatentable over Ishimori et al (US 2015/0004127 A1) in view of Ando et al (US 2017/0058116 A1) and Watanabe et al (US 2017/0341058 A1). The discussion with respect to Ishimori et al in paragraph 9 above is incorporated here by reference. Additionally, Ishimori et al teach suspension polymerizing a monomer mixture in the presence of a pore-forming agent (paragraph 0020) Ishimori et al are silent with respect to having a porous structure inside and having only one pore inside. However, Watanabe et al teach porous polymer particles (abstract) prepared by suspension polymerization (paragraph 0039). The porosity of the polymer particles can be controlled by the amount of porosifier. The size and shape of pores of the porous polymer particles can be controlled by the type of porosifier (paragraph 0044). The porous particles have a coating layers that covers at least a portion of the surface of the porous polymer particles (paragraph 0037). When the content of oils soluble surfactant is 5% by mass or more, since stability of water droplets becomes sufficient, it is easier for large single holes to be formed. When the content of oil-soluble surfactant is 80% by mass or less, it is easier for the porous polymer particles to maintain the shape after polymerization (paragraph 0048). The average particle size of porous polymer particles is preferably 300 microns or less and 10 microns or more (paragraph 0060). Therefore, in light of the teachings in Watanabe et al, and given that Ishimori et al contemplate preparing polymer particles by suspension polymerization and in the presence of pore-forming agents, it would have been obvious to one skilled in art prior to the filing of present application to optimize the amount of porosifier (i.e., pore-forming agent) and including oil-soluble surfactant in amounts of 5% by mass or more to obtain a porous polymer particles having a porous structure inside as in present claim 5 and only one pore inside thereof as in present claim 6, absent evidence to the contrary. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to KARUNA P REDDY whose telephone number is (571)272-6566. The examiner can normally be reached 8:30 AM to 5:00 PM M-F. 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, Arrie (Lanee) Reuther can be reached at 571-270-7026. 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. /KARUNA P REDDY/Primary Examiner, Art Unit 1764
Read full office action

Prosecution Timeline

Apr 24, 2024
Application Filed
Apr 23, 2026
Non-Final Rejection mailed — §103, §112
Jul 23, 2026
Response Filed
Aug 10, 2026
Final Rejection mailed — §103, §112 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

3-4
Expected OA Rounds
42%
Grant Probability
52%
With Interview (+9.9%)
3y 6m (~1y 2m remaining)
Median Time to Grant
Moderate
PTA Risk
Based on 842 resolved cases by this examiner. Grant probability derived from career allowance rate.

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