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 .
Response to Arguments
Applicant's arguments filed 4/24/2026 have been fully considered but they are not persuasive.
Applicant argues that the hydrophilic lubricant of Booth differs from the carboxylic acid-based additive of the present invention in terms of technical purposes and application process, as the former is used to prevent adhesion during compression whereas the latter is used to control particle agglomeration and pulverization characteristics in the cutting process of hydrogel polymer. This argument is unpersuasive since as admitted Booth relates to preventing adhesion of superabsorbent polymer and is a lubricant. One of ordinary skill in the art would recognize that Booth’s sodium stearyl fumarate lubricant preventing the adhesion of sodium acrylate polymer to punches is reasonably relevant to the prevention of adhesion of sodium acrylate polymer in the crushing process in Miyaki which blades are used to pulverize and which require the “lubricating effect of the surfactant” to crush more smoothly and without aggregation (see [0019]-[0022]).
In response to applicant's argument that the carboxylic-based additive of the present invention is used to control particle agglomeration and pulverization characteristics, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985). Furthermore, Miyaki teaches a method where a lubricating effect of a surfactant is used to control particle agglomeration and pulverization and since Booth’s sodium stearyl fumarate is a lubricating surfactant there is a reasonable expectation that sodium stearyl fumarate would also control particle agglomeration and pulverization characteristics in Miyaki’s process.
Claim Rejections - 35 USC § 103
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.
Claim(s) 1-2, 6-7, 9-12, 14, and 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Miyaki et al (JP-379210-B2 where citations are from the Machine Translation provided by the Examiner in the prior Office Action) in further view of Booth et al (WO-97/38740 submitted in the IDS filed 1/11/2023) and in further view of Weismantel (US 2008/0214749 submitted in the IDS filed ).
Miyaki teaches a method of making a water-absorbable resin, the method comprising:
polymerizing ethylenically unsaturated monomer in an aqueous solution the presence of a crosslinking agent, the neutralization rate of the monomer is in the range of 50 mol% to 99 mol%;
a polymer initiator is used at the start of polymerization;
the hydrogel is mixed with a surfactant before crushing to form a hydrogel disintegrated body; and
drying the hydrogel disintegrating body and pulverizing to obtain a water absorbent resin (see [0018], [0041-0042], and [0089-0090).
Miyaki further teaches a method where the surfactant is a fatty acid salts (i.e., a carboxylic acid salt) (see [0065]).
Miyaki does not disclose a carboxylic acid additive selected from the group consisting of carboxylic acid represented by Chemical Formula 1 and salts thereof.
Miyaki does not teach drying the mixture while alternatively introducing up-flow of 120°C to 210°C and down-flow of 120°C to 210°C to the mixture to form a base resin powder, wherein a total introduction time of the down-flow is longer than a total introduction time of the up-flow.
Regarding a carboxylic acid represented by Chemical Formula 1, Booth teaches a compressed absorbent aggregate comprising a superabsorbent crosslinked sodium polyacrylate polymer. Booth discloses a method wherein lubricants are used to prevent adherence of the aggregates to punch faces and dies used during tablet compression and where suitable lubricants include sodium stearyl fumarate (see Page 3, Ln 29 to Page 4, Ln 7 and Example 8). Sodium stearyl fumarate reads on a carboxylic acid salt of chemical formula 1 where A is C18 alkyl, B1 is -OCO- and B2 is -CH=CH-. It would have been obvious to one of ordinary skill in the art at the time of filing of the invention to perform the method as taught by Miyaki and Weismantel where the fatty acid salt surfactant used to reduce adhesion of particles during cutting comprises sodium stearyl fumarate as taught by Booth since it prevents adhesion of superabsorbent sodium polyacrylate particles.
Regarding the drying conditions, Weismantel teaches a process for producing water-absorbing polymer comprising:
polymerizing a monomer solution, comprising at least one ethylenically unsaturated acid-functional monomer and at least one crosslinker to form a hydrogel (see [0064-0070]); the acid groups of the hydrogels obtained have been partially neutralized where neutralization has been obtained by admixing neutralizing agent as an aqueous solution before polymerization by adding a portion of the neutralizing agent to the monomer solution (see [0091-0093]);
drying the resulting hydrogel by means of a heated gas stream by: effecting the drying in two or more temperature zones, and/or
the gas stream is flowed against the hydrogel upwardly in the downstream sector of the belt dryer, the direction of the flow being reversed at a water content of 15% to 45% by weight for the hydrogel; and/or
the hydrogel layer is flowed against in a belt dryer upwardly to some extant at least, the gas velocity being 5% to 30% of the gas velocity required to life the hydrogel off the belt.
Weismantel also discloses an example where upward drying lasts 11.8 minutes and downward drying lasts 25.2 minutes and where the upwardly directed airstream has a temperature of 165-180°C and the downwardly directed airstream has a temperature of 165-175°C (see Examples 1-4). Weismantel discloses that drying in his invention avoids partly overdried particles which are detrimental to the subsequent grinding and sieving (see [0006-0007]).
It would have been obvious to one of ordinary skill in the art at the time of filing of the invention to perform the method as disclosed by Miyaki where drying comprises alternately introducing up-flow of 165-180°C and down-flow of 165-175°C to form the base resin powder wherein the total introduction time of the down flow is longer than the up-flow as taught by Weismantel to prevent overdrying parts of the hydrogel as taught by Weismantel.
Regarding claim 2, Miyaki disclose a method where the hydrogel crushed body has average particle diameter of 1,800 µm (1.8 mm) (see [0091]).
Regarding claim 4, as applied above Booth discloses sodium stearyl fumarate which reads on where A is -C18H37.
Regarding claim 5, as applied above Booth discloses sodium stearyl fumarate which reads on where B1 is *-O-C-O-*.
Regarding claim 6, as applied above Booth discloses sodium stearyl fumarate where B2 is HC=CH.
Regarding claim 7, as applied above Booth discloses sodium stearyl fumarate which is an alkali metal salt.
Regarding claim 9, Miyaki discloses the method where the addition amount of the surfactant is within the range of 0.001 to 10 parts by weight with respect to 100 parts by weight of the hydrogel crosslinked polymer (i.e., 10 ppmw to 100,000 ppmw) (see [0070]).
Regarding claim 10, Weismantel discloses a method where the upflow time is 18% (see Example 6).
Regarding claim 11, as applied above, Weismantel teaches a belt dryer where the gas velocity is less than the gas velocity required to lift the hydrogel. Weismantel therefore teaches fixed-type dryer since the hydrogel stays stationary on the belt.
Regarding claim 12, Miyaki discloses where the crushed hydrogel is classified by a screen having a plurality of holes (see [0077-0078]) and where the diameter is 5 mm (see [0091]).
Regarding claim 14, Weismantel teaches a method where the water content of the dried polymer is most preferably up to 8% by weight (see [0041]). It would have been obvious to one of ordinary skill in the art at the time of filing of the invention to perform the method as taught by Miyaki and Weismantel where the water content after drying is in any range overlapping with Miyaki and Weismantel including the claimed range.
Regarding claim 16, Weismantel teaches a method comprising post crosslinking comprising spraying with a surface postcrosslinker and drying thermally (see [0070]). Drying thermally reads on heat treating.
Claim(s) 15-17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Miyaki, Booth, and Weismantel as applied to claim 1 and in further view of Braig et al (US 8,242,191).
As applied to claim 1, Miyaki, Booth, and Weismantel teach a method for preparing producing water-absorbing polymer resin comprising steps for conducting crosslinking polymerization to form a hydrogel polymer, mixing carboxylic acid-based additive with the hydrogel polymer and finely cutting to prepare a mixture comprising finely cut hydrogel; drying the mixture with alternately introduced up-flow and downflow to form base resin powder; and wherein the total introduction of the downflow is longer than the total introduction time of the upflow.
Regarding claim 15, Miyaki discloses a method comprising pulverizing (grinding) the dried crushed hydrogel (the base resin powder) (see Examples). Miyaki, Booth, and Weismantel do not disclose a method comprising classifying the base resin powder after grinding.
Braig discloses a method for producing water-absorbing particles based on ethylenically unsaturated monomers bearing acid groups, wherein the acid groups have been neutralized, the method comprising polymerizing in the presence of at least one crosslinker, and at least one initiator; comminuting the polymer gel; drying the polymer gel, then grinding and classifying the dried polymer gel to remove excessively small and large particles so that they can be recycled into the process (see Col 3, Line 31 to 38 and Col 6, Ln 13 to Col 7, Ln 38). It would have been obvious to one of ordinary skill in the art at the time of filing of the invention to perform the method as taught by Miyaki, Booth, and Weismantel the dried hydrogel material is classified after grinding as taught by Braig so that excessively small and large particles can be recycled to the process.
Regarding claim 16, Braig disclose a method where the polymer particles are surface postcrosslinked with a surface postcrosslinker and dried by heating (see Col 7, Ln 39 to Col 9, Ln 4).
Regarding claim 17, Braig discloses a method that produces a centrifuge retention capacity (CRC) as determined by EDANA test method No. WSP 241.2 of at least 26 g/g (see Col 9, Ln 64 to Col 10, Ln 1). It would have been obvious to one of ordinary skill in the art at the time of filing of the invention to perform the method as taught by Miyaki, Booth, Weismantel, Braig and produce a water-absorbing polymer with CRC in any overlapping range with at least 26 g/g including the claimed range.
Claim(s) 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Miyaki, Booth, and Weismantel or Miyaki, Booth, Weismantel and Braig as applied to claim 16 (which depends on claim 1 or 15) and in further view of Nam et al (KR-20180067940 which has a publication date of 6/21/2018 where US equivalent US-2020/00010624 is relied upon for citations).
As applied to claim 16, Miyaki, Booth, and Weismantel or Miyaki, Booth, Weismantel and Braig teach a method for preparing producing water-absorbing polymer resin comprising steps for conducting crosslinking polymerization to form a hydrogel polymer, mixing carboxylic acid-based additive with the hydrogel polymer and finely cutting to prepare a mixture comprising finely cut hydrogel; drying the mixture with alternately introduced up-flow and downflow to form base resin powder; and wherein the total introduction of the downflow is longer than the total introduction time of the upflow; and wherein the base resin powder is heat treated to surface crosslink, thus preparing superabsorbent polymer.
Regarding claim 15, Miyaki and Weismantel do not teach an absorbency under 0.3 psi pressure according to EDANA method WSP 242.3 of 24 g/g or more.
Nam discloses a method for preparing a super absorbent polymer having excellent performance comprising crosslinking a water-soluble ethylenically unsaturated monomer in the presence of an internal crosslinking agent to form a hydrogel polymer containing a first cross-linked polymer, drying, pulverizing, and classifying the hydrogel polymer to form a base polymer powder; and heat-treating and surface-crosslinking the base polymer (see Abstract and [0039-0044]). Nam discloses a method that produces a super absorbent polymer where AUP under a 0.3 psi in accordance with EDANA 242.3 is 25 or greater (see [0036] and [0122-0123]). It would have been obvious to one of ordinary skill in the art at the time of filing of the invention to perform the method as taught by Miyaki and Weismantel or Miyaki, Weismantel and Braig where the method produces absorbency under 0.3 psi pressure according to EDANA method WSP 242.3 of 24 g/g or more as taught by Nam so that it has excellent performance.
Allowable Subject Matter
Claims 8 and 13 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.
The following is a statement of reasons for the indication of allowable subject matter: The closest prior art of record does not teach the method of claim 1 further comprising the limitations of claims 8 or 13.
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 MICHAEL FORREST whose telephone number is (571)270-5833. The examiner can normally be reached Monday-Friday (10AM-6PM).
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sally A Merkling can be reached at (571)272-6297. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MICHAEL FORREST/Primary Examiner, Art Unit 1738
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