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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 May 4, 2026 has been entered.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1, 3 – 8, and 10 – 12 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Independent Claim 1 now sets forth a gel strength of the superabsorbent polymer is 0.65 N to 0.80 N, as measured according to the specified testing conditions. Claim 1 now additionally requires the chelating agent and capsule-type foaming agent each by including in an amount of 0.1 to 3 parts by weight, based on 100 parts by weight of the water-soluble ethylenically unsaturated monomer. While each of these limitations does appear to be supported individually by the original disclosure, the original disclosure does not appear to provide support for the currently claimed combination of both limitations.
Page 21, Lines 3 – 12, of the instant specification sets forth “Further, the superabsorbent polymer according to one embodiment of the present invention may provide a superabsorbent polymer having a higher absorption rate and excellent gel strength…In detail, 2.5 g of the superabsorbent polymer is immersed in 50 g of ascorbic acid saline and allowed to swell in an oven at 40°C for 24 hours. The swollen superabsorbent polymer has a gel strength of 0.50 N or more…preferably…0.65 N to 0.8 N” [emphasis added]. Thus, not all of the disclosed superabsorbent polymers have gel strength of 0.65 to 0.8 N, or even 0.50 N or more. Instead, there are certain embodiments in which the disclosed super absorbent polymers have a gel strength in these ranges. However, there is no general disclosure with respect to the amounts of chelating agent and capsule-type foaming agent provided in such embodiments, such that it can be concluded that superabsorbent polymers having gel strengths of 0.65 to 0.8 N are necessarily obtained when the chelating agent and capsule-type foaming agent are each provided in an amount of 0.1 to 3 parts by weight, based on 100 parts by weight of the water-soluble ethylenically unsaturated monomer.
Moreover, the disclosed examples do not test gel strength for amounts of chelating agent and capsule-type foaming agent over the entire claimed ranges for the amounts thereof (see Table 1). Additionally, Example 7 provides evidence that amounts of chelating agent and capsule-type foaming agent in the presently claimed ranges provides a gel strength outside in the instantly claimed range. Example 7 utilizes 0.1 or 0.15 parts by weight chelating agent and 0.3 parts by weight capsule-type foaming agent. The gel strengths of the obtained superabsorbent polymers are 0.82 N and 0.64 N respectively, which are outside the claimed range of 0.65 to 0.8 N (see Tables 1 and 2).
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.
Claims 1, 3, 4, 6 – 8, and 10 – 12 are rejected under 35 U.S.C. 103 as being unpatentable over US 2012/0001122 to Wattebled et al. (hereinafter Wattebled) in view of WO 2004/037903 to Reimann et al. (hereinafter Reimann) and US 2017/0014801 to Ikeuchi et al. (hereinafter Ikeuchi). For the purposes of examination, citations for Reimann are taken from an English-language equivalent of the document, US 2006/0057389.
Regarding Claims 1, 3, and 4. Wattebled teaches a method of preparing a superabsorbent polymer [0008].
The method comprising free-radically polymerizing an aqueous solution of an ethylenically unsaturated monomer having an acid group in the presence of a crosslinking agent to form a gel polymer [0038] – [0039], i.e. crosslinking polymerization of a water-soluble ethylenically unsaturated monomer in the presence of an internal crosslinking agent to form a water-containing gel polymer including a crosslinked polymer. The acid groups of the monomer may be partly or fully neutralized [0046]. The crosslinking polymerization further occurs in the presence of hollow bodies in which a hydrocarbon blowing agent is surrounded by a thermoplastic polymer material [0082] – [0084], i.e. a capsule-type foaming agent including a core comprising a hydrocarbon and a thermoplastic polymer shell surrounding said core.
The method of Wattebled further comprising drying and grinding the polymers [0041] – [0042], which would be reasonably expected to form a base polymer powder. A surface crosslinking step may subsequently be performed [0069] – [0070].
Wattebled further teaches the ethylenically saturated monomers (α1) and (α2) are provided in amounts of preferably 70 to 98.79 weight percent and 0.1 to 44.89 weight percent respectively. The crosslinker is provided in an amount of preferably 0.01 to 2.5 weight percent [0055] – [0056]. The hollow bodies/capsule-type foaming agent are provided in an amount of most preferably 0.1 to 3 weight percent [0111]. Using these values, the preferred amount of crosslinker in Wattebled can be calculated to be in the range of roughly 0.01 to 3.6 weight percent, while the preferred amount of capsule-type foaming agent can be calculated to be preferably in the range of roughly 0.1 to 7.2 weight percent relative to the 100 parts by weight of the ethylenically unsaturated monomer.
Wattebled does not expressly teach the internal crosslinking agent is epoxy-based. However, Reimann teaches the use of ethylene glycol diglycidyl ether as a crosslinking agent for ethylenically unsaturated monomers used in the preparation of absorbent polymers [0064]. The instant specification describes ethylene glycol diglycidyl ether as having an epoxy equivalent weight of 114 g/eq (see Footnote A1 of Table 1). Wattebled and Reimann are analogous art as they are from the same field of endeavor, namely methods of making absorbent polymers. Before the effective filing date of the instantly claimed invention, it would have been obvious to a person of ordinary skill in the art to provide ethylene glycol diglycidyl ether as the internal crosslinking agent in Wattebled. The motivation would have been that it has been held that it is obvious to select a known material based on its suitability for its intended use. See Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945); In re Leshin, 277 F.2d 197, 125 USPQ 416 (CCPA 1960); and MPEP 2144.07. In the instant case, Wattebled does teach the crosslinking agents disclosed by Reimann are suitably used in the disclosed method [0050] and Reimann expressly sets forth ethylene glycol diglycidyl ether as a crosslinking agent [0064].
Wattebled also does not expressly teach the crosslinking polymer is conducted in the presence of a chelating agent. However, Ikeuchi teaches the concept of adding a chelating agent during preparation of a water absorbing polymer, in an amount of up to 3 parts by weight of the solids content thereof [0319] – [0320]. Ikeuchi sets forth amino carboxylic acids as suitable chelating agents [0321] and uses diethylenetriamine pentaacetic acid in the inventive examples [0397]. Wattebled and Ikeuchi are analogous art as they are from the same field of endeavor, namely methods of making absorbent polymers. Before the effective filing date of the instantly claimed invention, it would have been obvious to a person of ordinary skill in the art to provide a chelating agent, e.g. an amino acid such as diethylenetriamine pentaacetic acid, in the amount taught by Ikeuchi during the crosslinking polymerization step of Wattebled. The motivation would have been that Ikeuchi teaches the addition of a chelating agent in this amount functions to prevent discoloration and improve the urine resistance of the articles in which it is incorporated [0319] – [0320].
The references are silent regarding the gel strength of the superabsorbent polymer obtained from their combination. Consequently, the Office recognizes that all of the claimed effects or physical properties are not positively stated by the reference(s). However, Wattebled, when modified with Reimann and Ikeuchi, in the manner proposed, teaches a process employing all of the claimed steps and processing conditions, as well as the claimed ingredients in the claimed amounts. Therefore, the claimed effects and physical properties, i.e. a gel strength in the instantly claimed range when measured under the instantly claimed conditions, would implicitly be achieved by a process employing all of the claimed steps and processing conditions, as well as the claimed ingredients in the claimed amounts. See In Re Spada, 911, F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990) and MPEP 2111.01 (I)(II). If it is applicant’s position that this would not be the case: (1) evidence would need to be provided to support the applicant’s position and (2) it would be the Office’s position that the application contains inadequate disclosure as to how to obtain the claimed properties using only the claimed process employing the claimed steps, processing conditions, and ingredients in the claimed amounts.
Regarding Claims 6 and 7. Wattebled teaches the method of Claim 1 wherein the ethylenically saturated monomers (α1) and (α2) are provided in amounts of preferably 70 to 98.79 weight percent and 0.1 to 44.89 weight percent respectively. The crosslinkers may be provided in an amount of preferably 0.01 to 2.5 weight percent [0055] – [0056]. The crosslinking component may include polyethylene glycol di(meth)acrylates [0050], which will provide a branched polymer of poly(meth)acrylic acid including polyalkylene glycol in side chains.
Regarding Claim 8. Wattebled teaches the method of Claim 1 wherein drying may be conducted at a temperature of 150°C for 2 hours ([0125] and [0127]).
Regarding Claims 10 – 12. Wattebled teaches the method of Claim 1 but is silent with respect to the claimed properties. Consequently, the Office recognizes that all of the claimed effects or physical properties are not positively stated by the reference(s). However, Wattebled, when modified in the manner proposed, teaches a process employing all of the claimed steps and processing conditions, as well as the claimed ingredients in the claimed amounts. Therefore, the claimed effects and physical properties - i.e. a superabsorbent polymer having an absorption rate, centrifuge retention capacity, and absorbency under pressure in the instantly claimed ranges - would implicitly be achieved by a process employing all of the claimed steps and processing conditions, as well as the claimed ingredients in the claimed amounts. See In Re Spada, 911, F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990) and MPEP 2111.01 (I)(II). If it is applicant’s position that this would not be the case: (1) evidence would need to be provided to support the applicant’s position and (2) it would be the Office’s position that the application contains inadequate disclosure as to how to obtain the claimed properties using only the claimed process employing the claimed steps, processing conditions, and ingredients in the claimed amounts.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over US 2012/0001122 to Wattebled et al. (hereinafter Wattebled) in view of WO 2004/037903 to Reimann et al. (hereinafter Reimann) and US 2017/0014801 to Ikeuchi et al. (hereinafter Ikeuchi) – as applied to Claim 1 above – and further in view of US 2022/0380617 to Fishman et al. (hereinafter Fishman).
Regarding Claim 5. Wattebled teaches the method of Claim 1 wherein the capsule-type foaming agent used may be EXPANCEL® 920 DU 40 [0086]. Fishman provides evidence that the hydrocarbon contained in the core of EXPANCEL® 920 DU 40 is iso-pentane and the shell is a polymer formed from methacrylonitrile (Table 1).
Response to Arguments
Applicant's arguments filed May 4, 2026 have been fully considered. The Office responds as follows:
Rejection under 35 U.S.C. 112
The Office agrees that the amendment to Claim 1 obviates the outstanding rejection under 35 U.S.C. 112(b). Accordingly, this rejection has been withdrawn.
Rejection under 35 U.S.C. 103
Applicant argues that the applied references only disclose some of three additives used in the polymerization step and none disclose the combined use of the additives in the specific content ratio. In response to applicant's arguments against the references individually, 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). The Office respectfully submits that the outstanding and present rejection under 35 U.S.C. 103 are based upon a combination of Wattebled with Reimann and Ikeuchi. For the reasons detailed in the rejection under 35 U.S.C. 103, it is the Office’s position that the claimed combination of additives in the specifically claimed content ratio are rendered obvious by Wattebled in light of the disclosures of Reimann and Ikeuchi.
Applicant additionally argues that the present specification describes various experimental data that demonstrates the effectiveness of the combinations of the three components used in the polymerization step. Applicant notes that Comparative Examples 4 and 5 illustrate the difficulty in forming the desired crosslinked structure, with gel strength significantly reduced compared to those of the inventive examples. Applicant also notes that Examples 8 and 9 fall outside the claimed content ranges and their properties show deterioration compared to Examples 1 – 7.
In response, it has been held that the evidence provided must compare the claimed subject matter with the closest prior art to be effective to rebut a prima facie case of obviousness. In re Burckel, 592 F.2d 1175, 201 USPQ 67 (CCPA 1979). The Office respectfully submits that Comparative Example 4 does not correspond to the closest prior art, Wattebled. Both the instant claims and Wattebled teaches the provision of a capsule foaming agent, while such an additive is not provided in Comparative Example 4.
Additionally, whether the unexpected results are the result of unexpectedly improved results or a property not taught by the prior art, the "objective evidence of nonobviousness must be commensurate in scope with the claims which the evidence is offered to support." In other words, the showing of unexpected results must be reviewed to see if the results occur over the entire claimed range. In re Clemens, 622 F.2d 1029, 1036, 206 USPQ 289, 296 (CCPA 1980)
The Office respectfully submits that the proffered data is still not commensurate in scope with the instant claims. The instant claims set forth a method in which any chelating agent and any capsule-type foaming agent including a hydrocarbon-containing core surrounded by a thermoplastic resin shell are each provided in an amount of 0.01 to 3 parts by weight per 100 parts by weight of the water-soluble ethylenically unsaturated monomer. On the other hand, the examples provided only utilize two species of chelating agents (EDTA-4Na and DTPA) in amounts of 0.1 to 0.5 parts by weight and two species of capsule-type foaming agent (F-36D and DTPA) in amounts of 0.1 to 3 parts by weight. This limited showing does not provide sufficient evidence to conclude that the alleged unexpected results would be achieved when any chelating agent is provided in any amount in the claimed range of 0.01 to 3 parts by weight per 100 parts by weight of the water-soluble ethylenically unsaturated monomer, as well as any capsule-type foaming agent having the claimed features in any amount in the claimed range of 0.01 to 3 parts by weight, as is instantly claimed.
Example 7 also provides evidence the alleged unexpected results do not occur over the entire claimed range. The superabsorbent polymer produced in Example 7 is prepared by a process employing all of the claimed steps and processing conditions, as well as the claimed ingredients in the claimed amounts, yet it has a gel strength outside in the instantly claimed range. Thus, alleged unexpected results, e.g. superior gel strength, are not provided by all amounts of chelating and capsule-type foaming agent in the instantly claimed ranges.
The outstanding rejection under 35 U.S.C. 103 has consequently been maintained.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MELISSA RIOJA whose telephone number is (571)270-3305. The examiner can normally be reached Monday - Friday 10:00 am - 6:30 pm EST.
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/MELISSA A RIOJA/ Primary Examiner, Art Unit 1764
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