DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claims 1 and 3-12 are pending as amended on 2/20/2026.
The new and modified grounds of rejection set forth below were necessitated by Applicant’s amendment. Therefore, this action is properly made final.
Any rejections and/or objections made in the previous Office action and not repeated below are hereby withdrawn. The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office Action.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph:
Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claim 10 is rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends.
Claim 10 depends from claim 1. However, the limitations recited in claim 10 have been added to claim 1 by amendment. Therefore, claim 10 no longer further limits claim 1. Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
Claim Rejections - 35 USC § 103
Claim(s) 1 and 3-12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al (US 2017/0283643) in view of Liu et al (US 2017/0233518).
As to claims 1, 9 and 10, Kim discloses a multi-staged emulsion polymerization method for preparing fine particles having an enclosed void using a core polymer containing carboxylic acid, a primary middle shell monomer, and a second hard shell monomer [0005]. The particles have enclosed voids and are used as opacifying agents [0001]. Regarding the last four lines of instant claim 1, Kim teaches that the primary middle shell polymer may be more hydrophobic than the core polymer, and more hydrophilic than the secondary hard shell polymer [0012]. The primary middle shell monomers include a multifunctional monomer that is a crosslinking monomer having two or more double bonds [0005].
As to instant step (a):
Kim exemplifies a process of preparing a primary middle shell polymer by adding a polymerization initiator (SPS) and a primary middle shell monomer (n-butylmethacrylate, methyl methacrylate, butylacrylate, methacrylic acid and arylmethacrylate) to a core polymer containing carboxylic acid [0073], meeting instant step (a).
As to instant step (b):
Kim further teaches that after the primary middle shell is polymerized, the polymerization of the hydrophobic secondary hard shell is performed simultaneously with neutralization for swelling the core, forming particles having enclosed voids [0047, 0026]. See also the exemplified process in [0075], wherein neutralizing swelling agent (ammonia) and secondary hard shell monomers (styrene, divinylbenzene) are added, followed by polymerization, meeting instant step (b).
As to instant step (c):
Kim further teaches that only some of the secondary hard shell monomers may be added in step (b) to perform the polymerization, and the rest of the secondary hard shell monomers are added and further polymerized in a subsequent step (c) [0006-7, 0027]. See also [0060-62]: Kim teaches a method wherein some of the secondary hard shell monomers are added for a first polymerization (corresponding to the polymerization recited in instant step (b), and then, remaining secondary hard shell monomers may be added without adding neutralization swelling agent for final polymerization of the secondary hard shell polymer [which corresponds to completing the polymerization in step (b) and forming enclosed voids, and then further adding secondary hard shell monomer to intermediate fine particles without adding neutralization swelling agent, followed by polymerization to form a secondary hard shell polymer, as recited in step (c)]. Kim fails to teach that residual polymerization initiator is removed during the final step of polymerizing secondary hard shell monomers, however, the addition of further monomer, and the step of further polymerizing, as taught by Kim, must consume polymerization initiator as it does in the presently claimed process, and therefore, Kim teaches a process wherein residual polymerization initiator must be removed by further adding monomer in step (c).
Kim teaches that the polymerization of the secondary hard shell is performed using styrene as a major component [0054]. Kim further teaches other suitable hydrophobic monomers for the secondary hard shell, such as hydroxyethyl(meth)acrylate etc… [0056]. However, Kim fails to teach adding a monomer having a phosphorus-containing acid group.
Like Kim, Liu teaches voided latex particles useful as non-film forming opacifiers [0001], and teaches a multi-stage emulsion polymerization process for forming voided latex particles by contacting a hydrophilic core and at least one intermediate shell with a swelling agent and polymerizing an outer shell [0005]. Liu teaches that the outer shell may be a homopolymer, but is more typically a copolymer, and bears one or more functional groups that may be varied and chosen as desired to modify certain characteristics of the voided latex particles, such as wet adhesion, scrub resistance, stain resistance, solvent resistance and block resistance properties of a coating composition which includes the voided latex particles. Liu names phosphate among examples of useful types of functional groups [0031], teaches introducing functional groups by polymerization of monomers bearing the desired functional groups [0032], and teaches providing the functional monomers at any stage, provided that polymers bearing the functional groups at least partially or completely reside in the outer shell polymer of the particles after swelling [0032]. Liu teaches an example of an outer shell which is a copolymer of styrene, and which contains from 0.1 to 10 wt% of monomer containing the functional group [0033]. Liu names 2-hydroxyethyl(meth)acrylates and ethylene glycol (meth)acrylate phosphate (EGMAP) as examples of a functionalized monomer [0035].
Considering Liu’s disclosure, the person having ordinary skill in the art would have been motivated to copolymerize styrene with an appropriate functional monomer when forming an outer shell of a voided latex particle in order to achieve desired characteristics such as wet adhesion, scrub resistance, stain resistance, solvent resistance and block resistance properties of a coating composition which includes the voided latex particles. It would have been obvious to the person having ordinary skill in the art, therefore, to have formed particles by adding secondary hard shell monomers for a first polymerization with neutralization swelling agent, and then adding remaining secondary hard shell monomers without adding neutralizing swelling agent for final polymerization of the secondary hard shell polymer, as taught by Kim (see [0060-62]), by including 0.1-10wt% of any appropriate functional monomer taught by Liu, such as EGMAP (which is recited in instant claim 9), within the secondary hard shell monomers in the final step of polymerization of the secondary hard shell polymer, in order to provide particles having desired functional groups, such as phosphate groups, residing in the outer shell of the particle.
Additionally (as to the recitation that no P-containing acid group monomer is present during steps (a) and (b)): As discussed above, Liu discloses that the functional groups are intended for imparting characteristics to the outer shell [0031], and are introduced into the outer shell polymer during formation of the polymer by copolymerization of monomers bearing the functional groups. Liu teaches adding the monomers at any stage provided the groups reside at least partially or completely in the outer shell of the particles [0032].
As set forth above, Kim teaches a method wherein some of the secondary hard shell monomers are added for a first polymerization, and then, remaining secondary hard shell monomers may be added without adding neutralization swelling agent for final polymerization of the secondary hard shell polymer [0060-62]. One having ordinary skill in the art would have recognized that in the synthesis of polymer particles via multi-stage emulsion polymerization (as taught in both Kim and Liu), successive polymerizations result in a successively formed layers of the particle, such that the monomers used in the final polymerization stage reside in the outermost shell of the particle. Therefore, when preparing a particle having successively formed shells via multi-staged emulsion polymerization by adding a comonomer having functional groups intended to impart characteristics by residing completely in the outer shell, the person having ordinary skill in the art would have been motivated to add the comonomer only during a final polymerization stage, in order to provide functional groups completely residing in the outermost shell of the particle (where the characteristics associated therewith are desired). It would have been obvious to the person having ordinary skill in the art, therefore, to have included Liu’s functional comonomer (e.g., EGMAP) only in Kim’s step (c) (wherein the final polymerization of secondary hard shell monomer occurs without neutralizing agent), in order to provide functional groups completely in the outermost shell/layer of the particle, such that the characteristics associated with the groups being located on the outer shell are maximally achieved.
As to the recitation in the preamble that the particles have “improved stain resistance:”
The claims are not limited to any particular degree of improvement, nor do the claims specify a baseline degree of stain resistance, nor a manner in which stain resistance is to be determined, nor any particular staining substance which must be resisted. Given the breadth of the recitation “improved stain resistance,” and given that a phosphate functionalized particle, as suggested by modified Kim, must have at least some degree of improved stain resistance to some staining substance as compared to some alternative particle, modified Kim suggests particles having “improved stain resistance” as presently recited.
As to claims 3 and 5-7, Kim discloses a combination of primary middle shell monomers in [0036] which are the same as those recited in instant claim 3. Kim discloses non-ionic unsaturated monomers in [0041] which are the same as those recited in claim 5. Kim discloses unsaturated monomers having one or two carboxyl groups in [0043] which are the same as those recited in claim 6. Kim discloses cross-linking monomers having two or more double bonds in [0039] which are the same as those recited in claim 7.
As to claim 4, modified Kim suggests a particle according to claim 3, as set forth above, wherein the hydrophilic core is formed from carboxyl-containing monomers (see, e.g., [0028]). Kim discloses that the primary middle shell polymer may be more hydrophobic than the core polymer and more hydrophilic than the secondary hard shell polymer [0012, 0035], meeting instant claim 10. Kim further teaches that it may be difficult to directly polymerize secondary hard shell monomers with the hydrophilic (i.e., carboxyl-containing) core, which is resolved by first polymerizing the primary middle shell polymer using low-hydrophobicity monomers [0034].
Kim teaches that the primary middle shell monomers include 1-10 wt% of an unsaturated monomer having one or two carboxyl groups [0036, 44], however, Kim fails to teach that the primary middle shell is formed by introducing a higher content of carboxyl-containing monomers in a first polymerization and a lower content of carboxyl-containing monomers in a second polymerization.
Liu similarly teaches an intermediate encapsulating layer formed by emulsion polymerization in the presence of the core. Liu teaches that the intermediate encapsulating layer functions as a compatibilizing layer and helps adhere the outer shell to the core [0029]. Like Kim, Liu teaches that the intermediate polymer contains a lower proportion of hydrophilic monomer than the core so that it swells less when contacted with swelling agent [0030]. Liu teaches that the particles may contain one or more intermediate encapsulating polymer layers [0029], and teaches that “at least one intermediate encapsulating polymer” may contain hydrophilic unsaturated monomers, while “other intermediate encapsulating polymers” may contain little or no hydrophilic unsaturated monomer [0030]. See also the teaching in [0048] that “more than one encapsulating polymer layer between core layer 2 and outer shell 4 may be present, if so desired” (last sentence).
Considering Liu’s and Kim’s disclosures, when forming a voided latex particle comprising a more hydrophilic (water swellable, carboxyl group-containing) core and a more hydrophobic (less swellable) outer shell, the person having ordinary skill in the art would have been motivated to include one or more intermediate layers having a hydrophilicity lower than that of the core and higher than that of the outer shell in order to compatibilize the core and outer shell, decrease difficulty associated with polymerizing the outer shell on the core, and improve adhesion of the outer shell to the core. The person having ordinary skill in the art would have been motivated to include multiple intermediate encapsulating polymer layers, as taught by Liu, in order to provide a desired degree of compatibilization between the core and the outer shell. It would have been obvious to the person having ordinary skill in the art, therefore, to have formed a voided particle comprising a middle/intermediate shell formed from carboxyl-functional monomers which is less hydrophilic than the core and more hydrophilic than the shell, as suggested by modified Kim, by successively polymerizing two or more middle/intermediate shell layers in order to provide a desired degree of compatibility between the hydrophilic core and the hydrophobic shell.
Additionally, one having ordinary skill in the art would have recognized that an increase in a content of carboxyl-containing monomers used to form an intermediate layer corresponds to an increase in the hydrophilicity of the intermediate layer (and thus, an increase in compatibility with the hydrophilic carboxy group-containing core). Therefore, when preparing a particle having two or more intermediate layers successively formed between the carboxy-containing hydrophilic core and the hydrophobic outer shell, it would have been obvious to the person having ordinary skill in the art to have formed the two or more intermediate layers with successively decreasing hydrophilicity (by successively decreasing the content of carboxyl-containing monomers in each intermediate layer forming-polymerization stage) in order to improve the compatibility of a given intermediate layer with the layer (or core) formed before it and the layer formed after it.
As to claim 8, Kim discloses the same agents as presently recited in [0051].
As to claims 11 and 12, Kim discloses a water-based paint and paper coating agent composition including the fine particles [0014].
Response to Arguments
Applicant's arguments filed 2/20/2026 have been fully considered.
In the paragraphs bridging pp 5-6 of the remarks filed on 2/20/2026, Applicant argues that Kim fails to disclose or suggest various limitations of the present claims, particularly, that Kim fails to teach the recited monomer having a phosphorus containing acid group. However, the argument regarding the failure of Kim to teach the phosphorus monomer is unpersuasive for at least the reason that Kim was not relied on individually for this teaching. One cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
Applicant argues (p 6, second paragraph, as well as on p 10) that Kim fails to teach a three-component hydrophilicity relationship. However, as set forth in paragraph 33 of the rejection mailed on 11/20/25, Kim discloses that the primary middle shell polymer may be more hydrophobic than the core polymer and more hydrophilic than the secondary hard shell polymer [0012, 0035]. Applicant has not explained why this teaching in Kim does not meet the recited relationship.
Applicant argues (pp 6-7) that Liu’s teaching that swelling and void formation occur concurrently with outer shell formation is fundamentally different from and incompatible with the claimed process. However, the rejection does not rely on Liu to modify portions of Kim which relate to the timing of neutralization swelling agent, swelling, and void formation. The rejection of record relied on Liu for a teaching to provide comonomers bearing a functional group in order to provide desired characteristics to the outer shell of the particle. In other words, the rejection sets forth that it would have been obvious to modify Kim’s process by including Liu’s functional comonomer in Kim’s step (c) (wherein the final polymerization of secondary hard shell monomer occurs without neutralizing agent), in order to provide functional groups completely in the outermost shell/layer of the particle. Therefore, Applicant’s argument is unpersuasive because the features of Liu which Applicant alleges to be distinct from the claimed invention were not relied on/incorporated into the disclosure of Kim. 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).
Applicant argues (pp 8-10) that the claimed process has been amended to require the absence of phosphorus-containing monomer in steps (a) and (b), such that the P-containing monomer is only added in separate step (c) which is conducted without neutralization swelling agent, after void formation is complete. The rejection of record has been modified to address the limitations regarding the absence of P-monomer in steps (a) and (b). The examiner further notes that there is no requirement in the present claims that P-monomer is added only after void formation is complete (nor does such a requirement appear to be described in the specification as originally filed.) Rather, step (c) requires adding the P-containing monomer “after formation of the enclosed voids…,” which encompasses methods wherein P-containing monomer is added after enclosed voids are formed, but does not require completion of void formation prior to addition of the monomer.
Applicant argues (p 10) that Kim does not teach addition of P-containing monomer for consuming residual initiator, and Liu does not mention residual initiator at all, and the lack of recognition of the problem in the prior art supports non-obviousness. However, Applicant has not challenged the Examiner’s assertion that polymerization initiator must be consumed (i.e., removed) by the addition of secondary hard shell monomers (including P-containing unsaturated monomer) in step (c) of the method suggested by modified Kim. Therefore, Applicant’s argument that there is no disclosure in the cited art regarding the consumption of initiator during the step (c) of adding/polymerizing monomer without neutralization swelling agent fails to establish the non-obviousness of the claimed method.
Applicant argues (pp 10-11) that the rejection relies on bodily incorporating Liu’s P-containing monomer into Kim’s process without regard to the specific temporal and compositional limitations recited in amended Claim 1, and lists several modifications to Liu’s process which would be required to result in the claimed process. However, the rejection cites Kim as a primary reference, and shows that Kim teaches a process which meets the claimed process, except for the addition of P-containing monomer during step (c). Liu is relied on as a secondary reference to establish the obviousness of including a P-containing monomer in Kim’s step (c). The rejection of claim 1 does not rely on bodily incorporation of any other method steps disclosed by Liu into the method disclosed by Kim, nor does the rejection of claim 1 start from, and then modify, Liu’s disclosed method in order to establish the obviousness of the claimed method. Therefore, Applicant’s arguments regarding bodily incorporation of Liu into Kim, and arguments regarding modifications to Liu which would be required to arrive at claim 1, fail to overcome the rejection of record.
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 RACHEL KAHN whose telephone number is (571)270-7346. The examiner can normally be reached Monday to Friday, 8-5.
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/RACHEL KAHN/ Primary Examiner, Art Unit 1766