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 .
This Office action is in response to the amendment filed 9/26/2025. Claims 1, 6 and 8 are amended; claims 8-11 are withdrawn from consideration as being drawn to non-elected invention. Accordingly, claims 1-12 are currently pending in the application.
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 § 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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-7 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Wolf et al (US 6,063,914) in view of Herfert et al (US 2006/0252913 A1).
Regarding claims 1 and 2, Wolf et al teach a swellable biodegradable starch maleate (title) which reads on biodegradable super absorbent polymer in present claim 1 and modified starch in present claim 2. See example 13, wherein physically modified starch is treated with maleic acid anhydride under alkaline conditions (i.e., pH of 8). The degree of substitution is 0.45. The obtained modified starch with maleic acid anhydride (i.e., reads on modified polysaccharide having a maleic acid group -OCOCH=CHCOOH- and at least part of maleic acid group is neutralized in present claim 1) is treated with pentaerythrite-tetrakis-(2-mercaptoacetate) and sodium bisulfite (col. 12, lines 32-52). The network make-up and aging stability can be combined with one another in a simple manner by the crosslinking of starch maleates with di- or oligothiols and the reaction of any residual maleate double bonds with thiols or sodium bisulfite (col. 7, lines 33-37) which reads on crosslinked polymer in present claim 1. The reaction of double bond of maleate with sodium bisulfite would result in the formation of sulfosuccinate (see example 1 of present application). Hence, it is the Office’s position that after reaction with sodium bisulfilte, the modified polysaccharide has a sulfosuccininc acid group -OCOCH(SO3H)CH2COOH- and at least part of which is neutralized (i.e., reads on the modified polysaccharide having a sulfosuccininc acid group -OCOCH(SO3H)CH2COOH- and at least part of sulfosuccinic acid group is neutralized in present claim 1).
Wolf et al fails to disclose in a single embodiment as in present claims superabsorbent polymer having the claimed degree of substitution of maleic acid group and sulfosuccinic acid group; and differs with respect to the species of internal crosslinking agent.
However, regarding polymer having the claimed degree of substitution of maleic acid group and sulfosuccinic acid group, Wolf et al in the general disclosure teach that other ester groups are present in amounts of less than 50% (col. 3, lines 59-67). Therefore, given that the degree of substitution in example 13 is 0.45 and other ester groups are present in amounts of less than 50%, it would have been obvious to one skilled in art prior to the filing of present application to prepare a modified polysaccharide with degree of substitution of maleic acid of 0.15 to 0.65 and degree of substitution of sulfosuccinic acid of 0.05 and 0.60, absent evidence to the contrary.
Regarding species of internal crosslinking agent, Herfert et al in the same field of endeavor teach superabsorbent polymer having long-term color stability (abstract). Examples of acidic SAP resins include starch-acrylic acid graft copolymers (paragraph 0034). The acidic and basic SAPs are crosslinked to a sufficient extent such that the SAP is water insoluble. Crosslinking renders the SAPs substantially water insoluble and in part serves to determine the absorption capacity of the SAPs (paragraph 0045). Preferred crosslinking agents include N,N’-methylenebis(meth)acrylamide, ethylene glycol dimethacrylate and trimethylolpropane trimethacrylate (paragraph 0050). Case law holds that selection of a known material based on its suitability for its intended use supported a prima facie obviousness determination in Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945). Therefore, in light of the teachings in Herfert et al, it would have been obvious to one skilled in art prior to the filing of present application to include crosslinking agents such as N,N’-methylene bis(meth)acrylamide, in the biodegradable superabsorber polymer, of Wolf et al, for above mentioned advantages.
Regarding claim 3, see example 13, of Wolf et al, wherein maleic acid anhydride is used in preparing the modified starch (col. 12, lines 32-39).
Regarding claim 4, see example 13, of Wolf et al, wherein the degree of substitution is 0.45 (col. 12, lines 32-42).
Regarding claim 5, See example 13, of Wolf et al, wherein physically modified starch is treated with maleic acid anhydride under alkaline conditions (i.e., pH of 8). The degree of substitution is 0.45. The obtained modified starch with maleic acid anhydride is treated with sodium bisulfite (col. 12, lines 32-52). The network make-up and aging stability can be combined with one another in a simple manner by the crosslinking of starch maleates and the reaction of any residual maleate double bonds with thiols or sodium bisulfite (col. 7, lines 33-37). The reaction of double bond of maleate with sodium bisulfite would result in the formation of sulfosuccinate (see example 1 of present application). Hence, it is the Office’s position that after reaction with sodium bisulfilte, the modified polysaccharide has a sulfosuccininc acid group -OCOCH(SO3H)CH2COOH- and at least part of which is neutralized. The other ester groups are present in amounts of less than 50% (col. 3, lines 59-67). Hence, the ratio of degree of substitution of the maleic acid group to the degree of substitution of the sulfosuccinate group falls within the claimed ratio of 1: 0.1 to 1: 3.0.
Regarding claim 6, Wolf et al teach that any native, modified or substituted starch can be used as the starch basis of the starch maleate including starches with high amylose content (col. 4, lines 56-61). It is noted that amylose is represented by formula:
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. Hence, it is the Office’s position that one skilled in art prior to the filing of present application would have a reasonable basis to expect starch containing high amylose content modified with maleic acid anhydride and then reacted with sodium bisulfite (example 13) to have the structures represented by formula 1-1 and 2-1 of claim 6, absent evidence to the contrary.
Regarding claim 7, examples of acidic resins, in Herfert et al, include starch-acrylic acid graft copolymers (paragraph 0034) which reads on acrylic acid based compound in present claim 7.
Regarding claim 12, Wolf et al teach that starch ester finds use as an absorption agent for the absorption of body fluids in hygiene, especially in diapers (col. 8, lines 58-61).
Response to Arguments
The rejections under 35 U.S.C. 103 as set forth in paragraphs 9-10, of office action, mailed 6/27/2025, are withdrawn in view of amendments and/or applicant arguments and/or new grounds of rejection set forth in this Office action, necessitated by amendment.
Applicant's arguments and Declaration under 37 CFR 1.132, filed 9/26/2025, have been fully considered but they are not persuasive. Specifically, applicant argues that (A) essence of Wolf is to use nucleophiles of general formulas I and/or II, and more specifically, a thiol, to react with the double bond of the maleic acid in the starch maleate to hinder aging of the swelling properties. In particular, Wolf teaches in the case of the thiol, no addition catalysts are generally necessary in order to make possible a rapid addition to the double bonds. Further, as demonstrated by the comparison data in the Declaration, the super absorbent polymer of Example 5, comprising a crosslinked polymer of a monomer including a modified polysaccharide having a maleic acid group (-OCOCH=CHCOOH) and a sulfosuccinic acid group (-OCOCH(SO₃H)CH₂COOH) each with a degree of substitution within the claimed ranges, and an internal crosslinking agent of polyethylene glycol diacrylate as claimed, provides much better absorption properties such as centrifuge retention capacity (CRC) and absorbency under pressure (AUP), and higher biodegradability, compared to Comparative Example A comprising a crosslinked polymer of the same monomer and an internal crosslinking agent of mercaptoethanol.
In response, Wolf et al teach physically modified starch is treated with maleic acid anhydride under alkaline conditions (i.e., pH of 8). The degree of substitution is 0.45. The obtained modified starch with maleic acid anhydride is treated with pentaerythrite-tetrakis-(2-mercaptoacetate) and sodium bisulfite. Graham V. Deere analysis was done and Herfert et al in the same field of endeavor teach that addition of internal crosslinking agent such as N,N’-methylenebis(meth)acrylamide renders the SAPs substantially water insoluble and in part serves to determine the absorption capacity of the SAPs (paragraph 0045). Hence, it is the Office’s position that one skilled in art prior to the filing of present application have a reasonable basis to expect addition of internal crosslinking agents, of Herfert et al, in the SAP, of Wolf et al to determine the absorption capacity, such as CRC and AUP. Additionally, the showing of unexpected results is not commensurate with scope of claims. Specifically, note that example 1, of present application which is based on modified Chitan has CRC and AUP that are inferior to that of SAP of Wolf et al (see Declaration filed, 9/26/2025, under 37 CFR 1.132).
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.
Contact Information
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.
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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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/KARUNA P REDDY/Primary Examiner, Art Unit 1764