Office Action 3: Notice of Allowance (2025-08-01)

CLAIMS:
Amendments to the Claims

This listing of claims will replace all prior versions, and listings, of claims in the application:

Listing of Claims:

1\. (Currently amended) A method of removing salts, by-products, and low molecular weight polymers from a solution of vinylamine-containing polymer\[\[s\]\] comprising;- providing the solution of vinylamine-containing polymer, wherein the polymer comprises salts and by-products formed during vinylamine- containing polymer synthesis and/or modification of a vinylamine-containing polymer solution;\- circulating the solution through a nanofiltration membrane and/or an ultrafiltration membrane having a molecular cutoff of from about 500 Dalton to 1,000 Dalton, thereby separating a low molecular weight from a high molecular weight retentate of the vinylamine-containing polymer and at least a portion of the salts and by-products; and- collecting the vinylamine-containing polymer retentate having a weight average molecular weight of from about 10,000 to about 1,000,000 Da. and a reduced amount of salts and by-products as compared to the solution prior to circulating through the nanofiltration membrane and/or an ultrafiltration membrane.

2\. (Cancelled)

3\. (Cancelled)

4\. (Currently amended) The method according to claim 1, wherein the salts and by- products are permeable molecules, unwanted reaction salts, small proteins, organic and/or inorganic solvents, residual monomers, monomeric impurities, monomer decomposition byproducts, monomer stabilizers, and byproducts from initiator decomposition, and/or impurities coming from cationizing and/or alkylating agent containing amine or amide functionality.

5\. (Currently amended) The method according to claim 4, wherein the salts and by- products are monomeric impurities.

6\. (Previously presented) The method according to claim 1, wherein the salts and by- products are impurities from reactions involving N-vinylformamide polymerization and copolymerization with other functional monomers, hydrolysis of polyvinylformamide by acid or caustic treatment, and post polymerization modification of vinylamine-containing polymers with functional monomers.

7\. (Original) The method of claim 1, wherein collecting the vinylamine-containing polymer retentate comprises collecting the vinylamine-containing polymer retentate having a higher concentration of vinylamine-containing polymer than the solution prior to circulating through the nanofiltration membrane and/or an ultrafiltration membrane.

8\. (Previously presented) The method according to claim 1, wherein the nanofiltration membrane and/or an ultrafiltration membrane has a molecular weight cut-off of 800 Da.

9\. (Original) A method of improving drainage in a papermaking process comprising adding the retentate according to claim 1, to a papermaking furnish.
10\. (Currently amended) A method of preparing a solution of high molecular weight vinylamine-containing polymers comprising,- providing a solution of vinylamine-containing polymer wherein the polymer comprises one or more of a salt or a by-product formed during vinylamine-containing polymer synthesis and/or modification of vinylamine containing polymer comprising a low molecular weight vinylamine polymer component and a high molecular weight vinylamine polymer component;

Attorney Docket: 11280US - circulating the solution through a nanofiltration and/or ultrafiltration membrane having a molecular weight cut-off of from about 500 Dalton to 1000 Dalton, thereby separating a fraction of low molecular weight vinylamine-containing polymer from a retentate having a weight average molecular weight of from about 10,000 to about 1,000,000 Da. ; and- collecting the retentate ,
wherein the weight average molecular weight of the collected fraction of the higher molecular vinylamine-containing polymer is from about 10,000 to about 1,000,000 Da.

11\. (Cancelled)

12\. (Cancelled)

13\. (Cancelled)

14\. (Currently amended) The method according to claim \[\[13\]\]10, wherein the weight average molecular weight of the collected fraction of vinylamine-containing polymer retentate is from about 100,000 to about 250,000 Da.

OFFICE ACTION:
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 7/17/2025 has been entered.
Response to Arguments
Applicant’s amendments and arguments, filed 7/17/2025, have been fully considered and are persuasive. All rejections have been withdrawn.
Examiner’s Amendment
An examiner’s amendment to the record appears below. Should the changes and/or additions be unacceptable to applicant, an amendment may be filed as provided by 37 CFR 1.312. To ensure consideration of such an amendment, it MUST be submitted no later than the payment of the issue fee.
Authorization for this examiner’s amendment was given in an interview with MICHAEL J. HERMAN on 7/22/2025.
The application has been amended as follows:
In Claim 1, 4th line from the end, the word “the” following the word “collecting” has been deleted and the word  --a--  inserted therefor.
Allowable Subject Matter
The following is an examiner’s statement of reasons for allowance: Decker et al and Bennett et al are the nearest prior art.  Decker et al discloses ultrafiltration of solutions of polymer containing vinylamine units through a membrane having a cut-off value from 1,000 to 500,000 Da, which touches the upper limit of the claimed range of about 500 Da to 1,000 Da. Decker et al prefers a cut-off from 10,000 to 300,000 Da.  Bennett et al discloses a cut-off preferably at least 2,000 or at least 4,000, such as from 9,000 to 100,000, with the cut-off dependent on the K value of the polymer. One of ordinary skill in the art would have been led to use a membrane cut-off significantly above the claimed range.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee.  Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Conclusion

APPLICANT REBUTTAL: REMARKS/ARGUMENTSClaims 1, 4-10, and 12-14, were pending in the application, claims 1, 4-10, and 12-14, have been rejected. Claims 1, 4, 5, 10, and 14, have been amended; and claims 12 and 13, cancelled.Therefore, claims 1, 4-10, and 14, are pending and under consideration. No new matter has been added.Amendments to the Claims Claim 1 has been amended to clarify that the present method relates to "removing salts, by-products, and low molecular weight polymers from a solution of vinylamine-containing polymer." The solution comprises salts and by-products, which in addition to removing at least a portion of the salts and by-products, separates a low molecular retentate from a high molecular weight retentate.Claims 4 and 5, have been amended so the wording coincides with the wording of amended claim 1, i.e., "wherein the salts and by-products..." (Abstract. Pg. 1, para. [0001]).Claim 10, has been amended to clarify that the retentate that is recovered has a weight average molecular weight of from about 10,000 to about 1,000,000. Applicant had inadvertently an unnecessarily limited the scope of the claim 10. Support can be found at page 6, para. [0030] and original claim 11.Claims 12 and 13 have been cancelled.CLAIM REJECTION UNDER 35 USC § 112 Claims 12-14, have been reject as being indefinite under 35 U.S.C. 112(d) or 35 U.S.C. 112 (pre-AIA), fourth paragraph. Specifically. claims 12-14 depend upon a cancelled claim.Applicants have cancelled claims 12 and 13; and have amended claim 14 to depend on claim 10.Therefore, this should now be considered moot.CLAIM REJECTION UNDER 35 USC § 103 Claims 1, 4-10, and 12-14, are rejected under 35 U.S.C. 103 as being unpatentable over US Patent 6,716,311 (hereinafter referred to as "Decker") in view of Bennett et al (US 2006/0065599). Applicants traverse this rejection.Applicants have been able to demonstrates improved drainage performance, indicating that the removal of low molecular weight polymer fractions, salts, and other impurities enhances product performance (see Table 3). Significantly, neither reference cited by the examiner discloses the performance benefits of being able to remove salts, by-products, and low molecular weight polymer species. The current studies and supporting data have shown significant performance improvements by not only removing salts and by-products but also provides a process for separating the higher molecular weight retentate from the lower molecular weight retentate.Decker relates to modified cationic polymers which are obtainable by reacting water- soluble polymeric compounds containing NH groups with crosslinking agents and processes for their preparation and their use in papermaking (col. 1, lines 5-9) . Although, Decker discloses passing a PVAM through a membrane filtration, the objective is to improve the reactivity between components a and b in the reaction.Applicants found using the current method, dry strength, wet strength, retention, and drainage in a papermaking process and product could be enhanced using the method as currently claimed. Based on the disclosure of Decker, there is no suggestion to include a circulation step in the process. Therefore, one of ordinary skill in the art would not be motivated to include the step with expectations of improved performance.As the Examiner submits, Decker fails to teach this certain critical aspects of the present technology, i.e., circulating the vinylamine-containing polymer through membranes having cut- offs below 1,000 Da. It is very relevant that Decker does not teach circulating the polymer through membranes having cut-offs offrom about 500 Da to 1,000 Da. In fact, Applicants teach in claim 8, that the cut-off is 800 Da.However, the Examiner alleges that Bennett, in the same field of endeavor, discloses a filtration process for reducing the content of water-soluble salts to achieve a reduced salt content.Applicants respectfully disagree that Decker and Bennett are in the same field of endeavor.Decker relates to modified cationic polymers which can be obtained by reacting (a) water- soluble, polymeric compounds containing NH groups with (b) compounds which are at least bifunctional with regard to NH groups and a method for producing the polymers by reacting the compounds of groups (a) and (b), and to the use of the modified cationic polymers during the production of paper as fixing agents for papermaking stock containing interfering substances (Abstract). Bennett relates to a process for reducing the content of water-soluble salts of aqueous solutions of polymers containing vinylamine groups by ultrafiltration and use of the polymers in the manufacture of multicomponent superabsorbent gels (pg. 1, para. [0001]). It is also the object of Bennett to "reducing the content of water soluble salts...with practically no loss of polyamine" (pg. 1, para. [0006], emphasis added).In addition, Bennett describes salt removal from a polymer solution with a polymer concentration of at least 7% by weight. This implies that the PVAm content in the diluted solution is at least 7%, excluding the salt. Paragraph [0046] further specifies that the results are based on a starting solution containing 13% sodium formate and 8% PVAm. However, the patent does not explicitly disclose a dilution factor.In contrast, Applicants clearly show (see Table 1) that the diluted polymer solution has a total solids content (polymer + salt) of 10.09%. The VSEP composite permeate collected has a solids content of 5.57%, indicating that the starting diluted polymer solution contains less than 7% polymer.Applicants have observed that the viscosity of the starting (diluted) polymer solution significantly affects membrane efficiency. This viscosity is influenced by polymer concentration, pH, salt content, and other factors.Looking at example 2 in Bennett (pg. 4, para. [0043]), it is taught that there is amine loss during ultrafiltration, indicating that there is polymer degradation during membrane processing.The results of the examples in the present application, i.e., the drainage performance data and comparison with the regular product (Table 3), provide indirect evidence that the polymer remains intact.It was only found through the careful selection of the membrane that removal of impurities could be accomplished with no loss of functional polymer or degradation of the polymer (pg. 5, para. [0021]).Finally, the current technology provides for a solution of vinylamine-containing polymer, wherein the polymer comprises salts and by-products formed during vinylamine-containing polymer synthesis and/or modification of a vinylamine-containing polymer solution. The objective of Decker is to provide novel polymers which are effective as fixing agents in papermaking (col. 1, lines 54-56). Different objectives are clearly met using different methods.To go even further, the Applicant herein cites the decision of the PTAB in Lenovo Holding Company, Inc., v. Photonic Imaging Solutions, Inc., (IPR2019-01075) for the Office's consideration. As the PTAB makes clear "[a] determination of obviousness cannot be reached where the record 'lacks explanation as to how or why the references would be combined to produce the claimed invention. The 'factual inquiry' into the reasons for 'combining references must be thorough and searching, and the need for specificity pervades.' Petitioner's statement that a POSITA could have...does not adequately explain how or why the referenced would have been combined to arrive at the claimed invention" (emphasis added). Moreover, the PTAB focuses on Belden Inc. v. Berk-Tek in citing that obviousness concerns whether a skilled artisan not only could have made but would have been motivated to make the combinations or modifications of prior art to arrive at the claimed invention.Decker relates to modified cationic polymers which are obtainable by reacting water- soluble polymeric compounds containing NH groups with crosslinking agents, processes for their preparation and their use in papermaking (Abstract, col. 1, lines 5-9). Bennett relates to a process for reducing the content of water-soluble salts of aqueous solutions of polymers containing vinylamine groups by ultrafiltration and use of the polymers in the manufacture of multicomponent superabsorbent gels (pg. 1, para. [0001]).CONCLUSIONIn view of Applicants' amendments and remarks, it is respectfully submitted that Examiner's rejections of claims 1-14, have been overcome. Accordingly, Applicants respectfully submit that the application, as amended, is now in condition for allowance, and such allowance is therefore earnestly requested. Should the Examiner have any questions or wish to further discuss this application and amended claims, Applicants request that the Examiner contact the Applicants' attorneys at 480-361-0466.No fees are believed to be due with this response. However, if there are any other fees required to have this amendment entered or to keep the application pending, the Commissioner is hereby authorized to charge Deposit Account No. 502091 for any fee which may be due.Respectfully submitted,