DETAILED ACTION
Response to Amendment
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
The new grounds of rejection set forth below are necessitated by applicant’s amendment filed on 6/3/2026. In particular, claim 1 has been amended to recite the first stage polymer include polybutadiene, the second stage includes styrene and methyl methacrylate, and to specify the organo-phosphorus monomer structure. This presents the claims in a manner with a scope not previously examined. Thus, the following action is properly made FINAL.
Claim Rejections - 35 USC § 103
Claim(s) 1, 5-14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Couffin (WO 2019/158609) in view of Rohrbach (US 2019/0270878).
Couffin teaches multistage polymer comprising a phosphorus moiety (abstract) where the first stage is polymerizing mixture A followed by a second stage for polymerizing mixture B (¶ 35) where mixture A or B comprising the phosphorus moiety (¶ 35). Couffin teaches the phosphorus is present in an amount of 350-2000 ppm (¶86-87) which corresponds to 0.035-0.2 wt%. Assuming the formula
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where m is 8, the molecular weight of the monomer is about 520 while phosphorus us about 31. Thus, the monomer is about 17 times larger than the phosphorus atom. This gives a range of about 0.6-3.4 wt%, which overlaps the claimed range of less than 1 wt% of claim 9. As the total amount of phosphorus monomer taught by Couffin overlaps the claimed range of less than 1 wt% in the first stage, the amount of phosphorus monomer in the first stage must also overlap because the amount in the first stage is equal to or less than the total amount of phosphorus present.
Couffin teaches the phosphorus moiety is in the first part (¶ 91) which meets claim 1. Couffin teaches the phosphorus moiety is in the second part (¶92) which meets claim 10. Couffin teaches phosphate group containing emulsifying agents (¶118) which corresponds to the claimed organophosphorus soap.
Couffin teaches the phosphorus moiety includes
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where m is 1-8 (¶99-100) which meets claim 5.
Couffin teaches the first stage is made by polymerizing butadiene with monomers such as styrene (¶70-72) and the second stage includes polymerizing styrene and alkyl (meth)acrylates (¶ 75-76) including methyl methacrylate (¶77-80).
Couffin teaches the ratio of A/B is 10/90 to 95/5 (¶53) which overlaps the range of claim 6. Couffin teaches the resulting polymer particle has a particle size of 20-1000 nm, preferably 50-900 nm (¶56) which meets the range of claim 8.
Couffin does not explicitly recite the amount of organophosphorus soap.
However, Rohrbach teaches multistage polymers which contain one or more phosphate surfactant in an amount of 50 ppm or more based on the dry weight of the polymer (abstract) such as polyoxyethylene alkyl ether phosphate salts (¶19). Rohrbach teaches using the composition in a polycarbonate matrix (¶41) where the amount of matrix to multistage polymer is 99:1 or higher (¶ 40) which meets claims 11-14. It would have been obvious to one of ordinary skill in the art to use the amount of phosphate surfactant because it improves heat stability (¶ 7).
Allowable Subject Matter
Claim 2 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Claim 2 recites the final stage further comprises one or more of alpha methyl styrene and butyl acrylate.
Couffin fails to teach the final stage includes alpha methyl styrene and butyl acrylate in addition to the styrene and methyl methacrylate of claim 1.
Response to Arguments
Applicant's arguments filed 6/3/2026 have been fully considered and are persuasive in part.
Applicant’s arguments regarding the rejections over by Kainz (US 2020/0262942) and Takamido (US 2016/0177016) are persuasive and these rejections are withdrawn.
Applicant’s arguments regarding the rejection over Couffin are not persuasive.
Applicant argues that the phosphorous moiety
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taught by Couffin is only with respect to the second polymer (B1) (corresponding to the claimed final stage) and does not apply to the phosphorus comprising moiety present in the polymer chain of (A1) (corresponding to the claimed first stage).
This is not persuasive because the Couffin explicitly teaches the monomer
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and because the portions cited to by Applicant discuss preferred embodiments. Couffin explicitly teaches the phosphorous containing moiety
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is covalently bound after polymerization (¶ 96). Additionally, the monomers taught by Couffin are not excluded from use in (A1). As Couffin fails to teach any way of covalently bonding the phosphorous containing moiety other than copolymerization, and because a specific monomer taught is
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, one of ordinary skill in the art would have used the taught monomers in either or both polymer chain (A1) and polymer chain (B1).
Regarding Applicant’s argument with respect to claim 9, Applicant argues that claim 9 refers to the overall content of the organophosphorous monomer in the first stage while Couffin is based solely on the phosphorous content and that phosphorous content cannot be correlated to the overall molecule content without accounting for the additional weight of other atoms int eh molecules.
This is not persuasive because the claimed range of the phosphorus monomer is less than 1 wt% while
Couffin teaches the phosphorus is present in an amount of 350-2000 ppm (¶86-87) which corresponds to 0.035-0.2 wt%. Assuming the formula
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where m is 8, the molecular weight of the monomer is about 520 while phosphorus us about 31. Thus, the monomer is about 17 times larger than the phosphorus atom. This gives a range of about 0.6-3.4 wt%, which overlaps the claimed range of less than 1 wt%. As the total amount of phosphorus monomer overlaps the range of less than 1 wt% in the first stage, the amount of phosphorus monomer in the first stage must also overlap.
Applicant argues that there is no reason to modify Couffin to arrive at the claimed invention absent improper hindsight. It appears Applicant is arguing improper hindsight in the application of the monomer to stage A1. This is not persuasive as discussed above. Furthermore, there is no contrary teaching in Couffin that states the monomer cannot be used in the stage A1, rather a preference that the monomer be used in stage B1. This does not preclude use of the monomer in the first stage.
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).
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 ROBERT C BOYLE whose telephone number is (571)270-7347. The examiner can normally be reached Monday-Thursday, 10am-4pm.
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.
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/ROBERT C BOYLE/Primary Examiner, Art Unit 1764
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