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 .
Reissue Applications
For reissue applications filed on or after September 16, 2012, all references to 35 U.S.C. 251 and 37 CFR 1.172, 1.175, and 3.73 are to the current provisions. This application, filed April 18, 2023, is a reissue of U.S. Patent 10,982,391 (hereafter the '391 patent), which issued from U.S. application Serial No. 16/305,967 (the ‘967 application) with claims 1-18 on April 20, 2021.
Scope of Claims
This reissue application contains claims 1-3, 5, 7, 9-11, 13, 14, 16, 17 and 19-28 directed to a method of enhancing paper strength properties and a composition. Independent claims 1 and 19, as presented in the amendment filed 12/04/2025, are representative:
1. (original) A method of enhancing paper strength properties, comprising treating a paper sheet precursor with
a polyaluminum salt; and
a strengthening agent, wherein the strengthening agent comprises a dialdehyde-modified polyacrylamide copolymer and a polyacrylamide copolymer in a molar ratio of from about 10:90 to about 90:10, wherein the dialdehyde-modified polyacrylamide copolymer is a cationic dialdehyde-modified polyacrylamide copolymer, and wherein the polyacrylamide copolymer is an amphoteric polyacrylamide copolymer,
wherein the polyaluminum salt is dosed at about 0.5 kilograms per ton of dry fibers to about 20 kilograms per ton of dry fibers,
wherein the strengthening agent is dosed at about 3 kilograms per ton of dry fibers to about 30 kilograms per ton of dry fibers.
19. (New) A composition, comprising: a polyaluminum salt and a strengthening agent,
wherein the strengthening agent comprises a dialdehyde-modified polyacrylamide copolymer and a polyacrylamide copolymer,
wherein the dialdehyde-modified polyacrylamide copolymer is a cationic dialdehyde-modified polyacrylamide copolymer, an anionic dialdehyde-modified polyacrylamide copolymer, or an amphoteric dialdehyde-modified polyacrylamide copolymer, and wherein the polyacrylamide copolymer is a cationic polyacrylamide copolymer, an anionic polyacrylamide copolymer, or an amphoteric polyacrylamide copolymer.
Rejections Overcome/Withdrawn
All rejections of claim 18 are moot in view of Applicant’s cancellation of the claim.
Prior art rejection Nos. 5 and 6 in the Office action mailed 08/04/2025 reject claims 19-22 and 24-28 based on Ban ‘549, and Ban ‘549 further in view of Dulko. These rejections are withdrawn to simplify issues since, as noted below and in Rejection No. 7 and 8 of said Office action, claims 19-22 and 24-28 are rejected based on a combination of prior art references that includes Ban ‘549.
Claim Objections
Claims 2 and 22 are objected to because of the following informalities: At line 2 in each of claims 2 and 22, the word “is” should be inserted after immediately before the word “from”. Appropriate correction is required.
Claim Rejection – 35 USC 251 Recapture
Claims 19-28 are rejected under 35 U.S.C. 251 as being an impermissible recapture of broadened claimed subject matter surrendered in the application for the patent upon which the present reissue is based. In re McDonald, 43 F.4th 1340, 1345, 2022 USPQ2d 745 (Fed. Cir. 2022); Greenliant Systems, Inc. et al v. Xicor LLC, 692 F.3d 1261, 103 USPQ2d 1951 (Fed. Cir. 2012); In re Youman, 679 F.3d 1335, 102 USPQ2d 1862 (Fed. Cir. 2012); In re Shahram Mostafazadeh and Joseph O. Smith, 643 F.3d 1353, 98 USPQ2d 1639 (Fed. Cir. 2011); North American Container, Inc. v. Plastipak Packaging, Inc., 415 F.3d 1335, 75 USPQ2d 1545 (Fed. Cir. 2005); Pannu v. Storz Instruments Inc., 258 F.3d 1366, 59 USPQ2d 1597 (Fed. Cir. 2001); Hester Industries, Inc. v. Stein, Inc., 142 F.3d 1472, 46 USPQ2d 1641 (Fed. Cir. 1998); In re Clement, 131 F.3d 1464, 45 USPQ2d 1161 (Fed. Cir. 1997); Ball Corp. v. United States, 729 F.2d 1429, 1436, 221 USPQ 289, 295 (Fed. Cir. 1984). The reissue application contains claim(s) that are broader than the issued patent claims. The record of the application for the patent family shows that the broadening aspect (in the reissue) relates to claimed subject matter that applicant previously surrendered during the prosecution of the application. Accordingly, the narrow scope of the claims in the patent was not an error within the meaning of 35 U.S.C. 251, and the broader scope of claim subject matter surrendered in the application for the patent cannot be recaptured by the filing of the present reissue application.
As noted in MPEP 1412.02.II, there is a three-step test for recapture: First, we determine whether, and in what respect, the reissue claims are broader in scope than the original patent claims. Second, we determine whether the broader aspects of the reissue claims relate to subject matter surrendered in the original prosecution. Third, we determine whether the reissue claims were materially narrowed in other respects, so that the claims may not have been enlarged, and hence avoid the recapture rule.
As to the first step of the recapture test, reissue claims 19-28 are broader than patented claim 1. For example, patented claim 1 sets forth the following requirements:
the dialdehyde-modified polyacrylamide copolymer and the polyacrylamide copolymer are in a molar ratio of from about 10:90 to about 90:10, wherein the dialdehyde-modified polyacrylamide copolymer is a cationic dialdehyde-modified polyacrylamide copolymer, and wherein the polyacrylamide copolymer is an amphoteric polyacrylamide copolymer;
wherein the polyaluminum salt is dosed at about 0.5 kilograms per ton of dry fibers to about 20 kilograms per ton of dry fibers,
wherein the strengthening agent is dosed at about 3 kilograms per ton of dry fibers to about 30 kilograms per ton of dry fibers.
These requirements are not present in reissue claims 19-28.
With respect to the second step of the recapture test, the broader aspects of reissue claims 19-28 relate to subject matter surrendered in the original prosecution. In particular, during prosecution of the ’391 patent in the ‘967 application, Applicant presented claims 1-20 on 11/30/2018. Claims 1, 2, 3, 9, 10 and 18 are pertinent and reproduced below:
PNG
media_image1.png
168
620
media_image1.png
Greyscale
PNG
media_image2.png
212
632
media_image2.png
Greyscale
PNG
media_image3.png
82
616
media_image3.png
Greyscale
PNG
media_image4.png
58
624
media_image4.png
Greyscale
PNG
media_image5.png
90
624
media_image5.png
Greyscale
In an Office action mailed 04/16/2020, claims 1, 3-4, 7-8, 13-20 were rejected under 35 U.S.C. 102(a)(1) as anticipated by or, in the alternative, under 35 U.S.C. 103 as obvious over WO 2011/130503 A2 to Ban et al (hereinafter “Ban”). Claims 1-20 were also rejected under 35 U.S.C. 103 as being unpatentable over WO 2015/038905 A1 to Zhu et al (hereinafter “Zhu”) as evidenced by Ban, U.S. Patent Application Publication No. 2012/0073773 A1, or U.S. Patent Application Publication No. 2014/0284011 A1.
In a response filed 06/29/2020, Applicant amended claim 1 to require that, for the strengthening aid, the dialdehyde-modified polyacrylamide copolymer and the polyacrylamide copolymer are in a molar ratio of from about 10:90 to about 90:10, the dialdehyde-modified polyacrylamide copolymer is a cationic dialdehyde-modified polyacrylamide copolymer, and the polyacrylamide copolymer is an amphoteric polyacrylamide copolymer. Claim 1 is reproduced below from the amendment filed 06/29/2020 and shows the amendment to the strengthening agent portion of claim 1:
PNG
media_image6.png
258
618
media_image6.png
Greyscale
In the accompanying Remarks filed 06/29/2020, with respect to the 102 rejection over Ban, Applicant argued (p. 5):
Without conceding the basis of the rejection, claim 1 has been amended to include the features of claim 10, which was not alleged to be anticipated by Ban. Thus, applicant respectfully submits that claim 1, as amended, and its dependent claims are not anticipated by Ban. Applicant respectfully requests that the rejections under 35 U.S.C. § 102(a)(1) be withdrawn.
With respect to the 103 rejections, Applicant further argued (p. 6, emphasis added):
Zhu fails to disclose treating the paper with a polyaluminum salt. To cure the deficiency, the rejection relies on Ban for allegedly teaching a polyaluminum salt. However, all the cited references fail to teach or suggest that the claimed method would produce an improvement in ash content and dewatering efficiency. Ban mentions aluminum compounds in a list of possible inorganic cationic coagulants but does not teach that combining an aluminum salt with the claimed strength aid would lead to the results shown in Figures 1 and 2.
Even if one of ordinary skill in the art would seek to combine the teachings of Zhu and Ban, it is not clear that one of ordinary skill in the art would combine an aluminum salt with a cationic dialdehyde-modified polyacrylamide copolymer because it would be redundant. Ban teaches that the cationic coagulant could be an inorganic compound but does not teach that the inorganic compounds can be used in combination with the cationic organic coagulants.
As noted above, the claimed strength aid was amended to require the limitation that the dialdehyde-modified polyacrylamide copolymer and the polyacrylamide copolymer are in a molar ratio of from about 10:90 to about 90:10, the dialdehyde-modified polyacrylamide copolymer is a cationic dialdehyde-modified polyacrylamide copolymer, and the polyacrylamide copolymer is an amphoteric polyacrylamide copolymer. Thus, this limitation is a surrender generating limitation.
In a subsequent final rejection mailed 09/09/2020, claims 1-2, 5-8 and 11-20 were rejected under 35 USC 103 over Zhu as evidenced by Ban and Jehn-Rendu or Krapsch. In a response filed 12/07/2020, Applicant amended claim 1 as follows:
PNG
media_image7.png
288
492
media_image7.png
Greyscale
In the accompany remarks filed 12/07/2020, Applicant argued that amended claim 1 is patentable because Applicants have shown unexpectedly improved paper strength in Fig. 1, and “[t]he improvement was observed at both dosages of 7.5 kg/ton and 15 kg/ton.” (See pp. 6-7). Claim 1 subsequently issued as claim 1 of the ‘391 patent. Accordingly, the requirement that the polyaluminum salt is dosed at about 0.5 kilograms per ton of dry fibers to about 20 kilograms per ton of dry fibers and the strengthening agent is dosed at about 3 kilograms per ton of dry fibers to about 30 kilograms per ton of dry fibers is another surrender generating limitation.
Accordingly, the broadening aspects noted above in reissue claims 19-28 relate to subject matter surrendered in the original prosecution.
With respect to the third step of the recapture test, independent reissue claim 19 and its dependent claims 20-28 have broadened the surrender generating limitations but the broadened aspects were well known in the prior art, and thus, there is recapture. See MPEP 1412.02.III.B.4.
In particular, reissue claims 19, 22 and 27 require that the dialdehyde-modified polyacrylamide copolymer is a cationic dialdehyde-modified polyacrylamide copolymer, an anionic dialdehyde-modified polyacrylamide copolymer, or an amphoteric dialdehyde-modified polyacrylamide copolymer. Reissue claim 23 requires that the dialdehyde-modified polyacrylamide copolymer is an anionic dialdehyde-modified polyacrylamide copolymer.
However, the Zhu reference teaches a paper-making aid comprising a dialdehyde-modified polyacrylamide strengthening agent wherein the dialdehyde-modified polyacrylamide-type strengthening agent is selected from the group consisting of cationic dialdehyde-modified polyacrylamide-type strengthening agents, anionic dialdehyde-modified polyacrylamide-type strengthening agents and amphoteric dialdehyde-modified polyacrylamide-type strengthening agents (see Abstract and ¶ 0009).
Reissue claim 19 further requires that the polyacrylamide copolymer is a cationic polyacrylamide copolymer, an anionic polyacrylamide copolymer, or an amphoteric polyacrylamide copolymer. Reissue claim 24 requires that the polyacrylamide copolymer is a cationic polyacrylamide copolymer. Reissue claim 25 depends from claim 24 and requires that the cationic polyacrylamide copolymer comprises from about 1 mol % to about 60 mol % of a cationic monomer.
However, Zhu further teaches that the strengthening agent comprises polyacrylamide-type strengthening agent, wherein the polyacrylamide-type strengthening agent is selected from a group consisting of cationic polyacrylamide-type strengthening agents, anionic polyacrylamide-type strengthening agents and amphoteric polyacrylamide-type strengthening agent (see ¶ 0009). Zhu further teaches a cationic monomer content of 0.1-50 mole% (see ¶ 0037).
Reissue claims 20, 21, 26 and 28 add limitations with respect to the polyaluminum salt, the pH of the composition, or the composition comprising a solution, suspension, a solid, a powder or a gel. These limitations are unrelated to the surrender generating requirement that the dialdehyde-modified polyacrylamide copolymer and the polyacrylamide copolymer are in a molar ratio of from about 10:90 to about 90:10, the dialdehyde-modified polyacrylamide copolymer is a cationic dialdehyde-modified polyacrylamide copolymer, and the polyacrylamide copolymer is an amphoteric polyacrylamide copolymer. Thus, claims 20, 21, 26 and 28 do not avoid the recapture rule. See MPEP 1412.02.III.B.1.
Accordingly, reissue claims 19-28 present broadening aspects which relate to claimed subject matter that Applicant previously surrendered during the prosecution of the ‘091 patent. Therefore, the narrow scope of the claims in the patent was not an error within the meaning of 35 U.S.C. 251, and the broader scope of claimed subject matter surrendered in the application for the patent cannot be recaptured by the filing of the present reissue application.
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, 5, 7, 9-11, 14, 16, 17, 19, 20 and 22-28 are rejected under 35 U.S.C. 103 as being unpatentable over JP 62-125096 to Yoshioka et al (hereinafter “Yoshioka”) in combination with WO 2015/038905 A1 to Zhu et al (hereafter “Zhu”). The English translation attached to Yoshioka is hereinafter referred to below. The translation does not have page numbers, but is a total of 18 pages. The translation page numbers are hereinafter referred to as first, second, third, etc.
With respect to claims 1, 2, 11, 17, 19, 20, 22, 23 and 27, Yoshioka teaches a method of improving filler retention in a papermaking process, wherein the method also provides an excellent paper strength-enhancing effect (see the fourth and seventh pages). The method comprises treating raw pulp, i.e., instant paper sheet precursor, with a combination of an amphoteric polyacrylamide copolymer and an aluminum compound such as polyaluminum chloride or polyaluminum hydroxide (see the sixth and seventh pages).
Yoshioka teaches that the aluminum compound is dosed at preferably 0.05 to 1% by weight of the dry weight of the pulp, i.e., dry fibers, in the papermaking raw material (see the second and seventh pages). The 0.05 to 1% by weight is equivalent to 0.5 to 9.1 kg/ton, which overlaps the claimed range. In fact, for example, in Yoshioka’s Example 2, the “PAC”, i.e., polyaluminum chloride, content is 0.1% or 0.12%. i.e., 0.9 kg/ton or 1.8 kg/ton, respectively.
Yoshioka teaches that the amphoteric polyacrylamide copolymer is dosed at preferably 0.1 to 3% by weight of the dry weight of the pulp, i.e., dry fibers, in the papermaking raw material (see the second and sixth pages). The 0.1 to 3% by weight is equivalent to 0.9 to 27.2 kg/ton, which closely overlaps the claimed range of about 3 to about 30 kg/ton. Yoshioka’s Example 2 uses 0.4%, i.e., 3.6 kg/ton, of the amphoteric polyacrylamide copolymer.
Yoshika teaches that the combination of an amphoteric polyacrylamide copolymer and aluminum compound shows a tremendous synergistic effect (see eighth page). Yoshioka teaches that other papermaking additives can be added in the usual manner (see seventh page). Yoshioka’s invention does not in any way preclude the use of other papermaking additives (see seventh page).
Yoshioka does not teach further treating the pulp with a cationic dialdehyde-modified polyacrylamide copolymer.
Zhu teaches a papermaking composition for addition to pulp, wherein the composition includes a strengthening agent comprising a dialdehyde-modified polyacrylamide and a polyacrylamide (see ¶¶ 0008-0009, 0024, 0037 and 0071-0075). The dialdehyde-modified polyacrylamide-type strengthening agent is selected from the group consisting of cationic dialdehyde-modified polyacrylamide-type strengthening agents, anionic dialdehyde-modified polyacrylamide-type strengthening agents and amphoteric dialdehyde-modified polyacrylamide-type strengthening agents (see ¶ 0009). The polyacrylamide strengthening agent is selected from the group consisting of cationic polyacrylamide copolymer strengthening agents, anionic polyacrylamide copolymer strengthening agents and amphoteric polyacrylamide copolymer strengthening agents (see ¶¶ 0009 and 0034).
Zhu teaches that the dosage of the sum of the dialdehyde-modified polyacrylamide-type strengthening agent(s) and the polyacrylamide-type strengthening agent(s) relative to the dry fiber in the pulp slurry is between 0.1 kg/ton dry fiber and 10 kg/ton dry fiber, e.g., between 1 kg/ton dry fiber and 10 kg/ton dry fiber (see ¶¶ 0071 and 0094).
Zhu teaches that the weight ratio between the dialdehyde-modified polyacrylamide and the polyacrylamide can be suitably selected by one skilled in the art according to the strength properties of the desired paper (see ¶ 0044). In particular, Zhu teaches that in order to effectively increase ash retention in the finished paper and/or paper strength, the dialdehyde-modified polyacrylamide-type strengthening agent and amphoteric polyacrylamide strengthening agent can have a ratio of solid contents such as 1:99-99:1, e.g., 10:90-90:10, e.g., 30:70-70:30, e.g., 40:60-60:40, e.g., 50:50 (see ¶ 0044). In fact, Zhu’s Example 2 (¶¶ 00144-00145) uses a 1:1 weight ratio of dialdehyde-modified polyacrylamide copolymer, i.e., GPAM copolymer solution 1, and amphoteric polyacrylamide copolymer 1, which each have a molecular weight of 1.2 million Daltons (see ¶¶ 00116 and 00133-00134). Thus, Zhu’s Example 2 has a molar ratio of 50:50 as per claim 1 and its dependent claims, and claim 22.
Zhu further teaches that the paper-making composition can may contain other chemical aids for paper-making (see ¶ 0046).
Zhu teaches that its composition containing the dialdehyde-modified polyacrylamide and the polyacrylamide provides the advantages of substantially increased ash retention and/or increased strength of the paper (see ¶¶ 0012 and 0067-0068).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have further included a cationic dialdehyde-modified polyacrylamide copolymer in Yoshioka’s pulp treatment that already uses a combination of an amphoteric polyacrylamide copolymer and an aluminum compound because Yoshioka specifically teaches that the treatment does not preclude the use of other paper-making additives, and the use of a combination of a dialdehyde-modified polyacrylamide and a polyacrylamide, e.g., an amphoteric polyacrylamide copolymer, provides the advantages of substantially increased ash retention and/or increased strength of the paper, as taught by Zhu.
Alternatively, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have included Yoshioka’s aluminum compound, such as polyaluminum chloride or polyaluminum hydroxide, in Zhu’s paper-making composition because Zhu specifically teaches that other chemical aids can be contained in the composition, and so as to take advantage of the fact that the combination of an amphoteric polyacrylamide copolymer (already present in Zhu’s composition) and an aluminum compound provides for a synergistic effect, improves filler retention and provides for an excellent paper strength-enhancing effect, as taught by Yoshioka. Indeed, Zhu teaches use of fillers (see ¶¶ 0075 and 0083).
With respect to claim 3, Zhu teaches that the dialdehyde-modified polyacrylamide copolymer comprises acrylamide and one or more cationic monomer(s) derived from a monomer selected from diallyldimethylammonium chloride, N-(3-dimethylaminopropyl)methacrylamide, N-(3-dimethylaminopropyl)acrylamide, trimethyl-2-methacroyloxyethylammonium chloride, trimethyl-2-acroyloxyethylammonium chloride, methylacryloxyethyldimethyl benzyl ammounium chloride, acryloxyethyldimethyl benzyl ammounium chloride, (3-acrylamidopropyl)trimethylammonium chloride, (3-methacrylamidopropyl)trimethylammonium chloride, (3-acrylamido-3-methylbutyl)trimethylammonium chloride 2-vinylpyridine, 2-(dimethylamino)ethyl methacrylate, and 2-(dimethylamino)ethyl acrylate (see ¶¶ 0018 and 0024).
With respect to claim 5, Zhu teaches that the dialdehyde of the dialdehyde-modified polyacrylamide copolymer can be glyoxal, malonaldehyde, succinic aldehyde or glutaraldehyde (see ¶ 0023).
With respect to claim 7, Zhu teaches that the amphoteric polyacrylamide polymer comprises acrylamide and a cationic monomer which can be one or more selected from the group consisting of diallyldimethylammonium chloride, N-(3-dimethylaminopropyl)methacrylamide, N-(3-dimethylaminopropyl)acrylamide, trimethyl-2-methacroyloxyethylammonium chloride, trimethyl-2-acroyloxyethylammonium chloride, methylacryloxyethyldimethyl benzyl ammounium chloride, acryloxyethyldimethyl benzyl ammounium chloride, (3-acrylamidopropyl)trimethylammonium chloride, (3-methacrylamidopropyl)trimethylammonium chloride, (3-acrylamido-3-methylbutyl)trimethylammonium chloride 2-vinylpyridine, 2-(dimethylamino)ethyl methacrylate, and 2-(dimethylamino)ethyl acrylate (see ¶¶ 0018, 0034-0035 and 0037).
Likewise, Yoshioka teaches that the amphoteric polyacrylamide polymer contains acrylamide and a cationic monomer such as di- or tri-alkylaminoalkyl acrylates, di- or tri-alkylaminoalkyl methacrylates, di- or tri-alkylaminoalkyl acrylamides, di- or tri-alkylaminoalkyl methacrylamides, etc. (See the fifth page).
With respect to claim 9, Zhu teaches that the dialdehyde-modified polyacrylamide copolymer has a weight average molecular weight of 100,000-10,000,000 Daltons, i.e., 100 kDa to 10,000 kDa, as here claimed (see ¶ 0029).
With respect to claim 10, Yoshioka teaches that the amphoteric acrylamide polymer has a molecular weight of preferably 200,000 to 3,000,000, i.e., 200 kDa to 3,000 kDa, as here claimed (see the sixth page). Likewise, Zhu teaches that its polyacrylamide polymer has a weight average molecular weight of 100,000-10,000,000 Daltons, i.e., 100 kDa to 10,000 kDa, as here claimed.
With respect to claims 14 and 16, as noted above, it would have been obvious to have included Yoshioka’s polyaluminum compound in Zhu’s paper-making composition. Thus, the polyaluminum compound, dialdehyde-modified polyacrylamide copolymer and amphoteric polyacrylamide copolymer are combined into a composition prior to being delivered to the pulp, and thus, are delivered simultaneously to the pulp.
Alternatively, Yoshioka teaches that the amphoteric polyacrylamide copolymer and aluminum compound can be added in any order, i.e., individually, or they can be delivered simultaneously (see the last ¶ on the seventh page). Zhu’s paper-making additive is a composition containing dialdehyde-modified polyacrylamide copolymer and amphoteric polyacrylamide copolymer. Thus, it would have been obvious for a skilled artisan to have added Zhu’s paper-making additive composition and Yoshioka’s aluminum compound individually or simultaneously, as per the teachings of Yoshioka. Further, any order of performing process steps is prima facie obvious in the absence of new or unexpected results. See MPEP § 2144.04(IV)(C).
With respect to claims 24 and 25, Yoshioka and Zhu do not require the presence of a cationic polyacrylamide copolymer in addition to Yoshioka’s amphoteric polyacrylamide copolymer.
However, Zhu teaches that its paper-making composition can contain plural polyacrylamide-type strengthening agents, and that the polyacrylamide strengthening agent is selected from the group consisting of cationic polyacrylamide copolymer strengthening agents, anionic polyacrylamide copolymer strengthening agents and amphoteric polyacrylamide copolymer strengthening agents (see ¶¶ 0009 and 0034).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have included a cationic polyacrylamide copolymer in the paper-making additive composition of Yoshioka and Zhu because Zhu teaches that plural polyacrylamide strengthening agent selected from the group consisting of cationic polyacrylamide copolymer strengthening agents, anionic polyacrylamide copolymer strengthening agents and amphoteric polyacrylamide copolymer strengthening agents can be present in the composition.
Further with respect to claim 25, Zhu teaches that the cationic polyacrylamide copolymer comprises from 0.1-50 mol%, e.g., 1-20 mol% cationic monomer (see ¶0037).
With respect to claim 26, Zhu teaches that the paper-making composition has a pH value of 6.0 or above, e.g., 6.5-13.0, e.g., 7.0-12.0, e.g., 7.5-11.0, e.g., 8.0-10.0 (see ¶ 0048), each of which overlaps and thus, renders obvious the claimed pH range of about 6 to about 9. See MPEP 2144.05.I. In fact, the compositions in Zhu’s Examples 1, 2, 4, 5 and 6 have a respective pH of 6.8, 7.5. 7.8, 8.5 and 8.1, as here claimed (see ¶¶ 00142, 00145, 00149, 00151, and 00153).
With respect to claim 28, Zhu teaches that the paper-making composition can be in the form of a solution or a dispersion, and is added to pulp forming a suspension (see ¶¶ 0066, 0075 and 0078).
Claims 13 and 21 are rejected under 35 U.S.C. 103 as being unpatentable over the combination of Yoshioka and Zhu as applied to claims 1-3, 5, 7, 9-11, 14, 16, 17, 19, 20 and 22-28 above, and further in view of WO 97/11029 A2 to Dulko (hereinafter “Dulko”).
Yoshioka and Zhu, as relied upon for the reasons stated above in Rejection No. 2, differ from claims 13 and 21 in that Yoshioka does not specifically teach the aluminum compound, e.g., polyaluminum chloride, has a basicity of from about 40% to 83%.
Dulko teaches that polyaluminum chlorides and polyaluminum chlorosulfates are compounds used as flocculents and coagulants for water and wastewater treatment, and are also used in the production of paper (see p. 1, lines 7-12). Dulko teaches a process for production of polyaluminum chlorides and polyaluminum chlorosulfates (see abstract).
Dulko prepares the polyaluminum chlorides and polyaluminum chlorosulfates with basicities of greater than 70% using, as starting material, basic aluminum chlorides and basic aluminum chlorosulfates of low basicity (25% or less). The polyaluminum chlorides and polyaluminum chlorosulfates produced remain fluid, i.e., they do not coalesce into a gel, and the formation of calcium sulfate precipitates can be avoided. Further, they can be produced without the addition of heat, thus avoiding the formation of undesirable byproducts. As a result, the process is particularly well-suited to large scale industrial applications. (See p. 2, lines 19-26).
In Example 8, Dulko prepares polyaluminum chloride having a basicity of 83% (see p. 20, lines 12-24). In Example 6, Dulko prepares polyaluminum chlorosulfate having a basicity of 50% (see p. 19, lines 20-29).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used Dulko’s polyaluminum salt having a basicity of, e.g., 83% or 50%, as the aluminum compound in the method and composition of Yoshioka and Zhu because Dulko teaches that its polyaluminum salt, i.e., polyaluminum chlorides or polyaluminum chlorosulfates, can be used in the production of paper, and because the polyaluminum chlorides or polyaluminum chlorosulfates can be produced for large scale industrial applications, as taught by Dulko.
Claims 19-20 and 22-28 are rejected under 35 U.S.C. 103 as being unpatentable over Zhu in view of US Patent Application Publication 2012/0103549 to Ban (hereinafter “Ban ‘549”), US Patent Application Publication No. 2012/0073773 to Jehn-Rendu et al (hereafter “Jehn-Rendu”) and US Patent Application Publication No. 2014/0284011 to Krapsch et al (hereafter “Krapsch”).
With regard to claims 19-20, 23 and 24, Zhu teaches a papermaking composition including a strengthening agent comprising a dialdehyde-modified polyacrylamide and a polyacrylamide (see ¶¶ 0008-0009, 0024 and 0037). The dialdehyde-modified polyacrylamide-type strengthening agent is selected from the group consisting of cationic dialdehyde-modified polyacrylamide-type strengthening agents, anionic dialdehyde-modified polyacrylamide-type strengthening agents and amphoteric dialdehyde-modified polyacrylamide-type strengthening agents (see ¶ 0009). The polyacrylamide strengthening agent is selected from the group consisting of cationic polyacrylamide copolymer strengthening agents, anionic polyacrylamide copolymer strengthening agents and amphoteric polyacrylamide copolymer strengthening agents (see ¶¶ 0009 and 0034).
Zhu teaches that the papermaking composition can contain other chemical aids for paper making (see ¶ 0046). Zhu differs from the claims in not teaching that the papermaking composition further comprises a polyaluminum salt.
However, the use of polyaluminum salts along with strengthening agents is well-known in the art as shown by Ban ‘549, Jehn-Rendu and Krapsch.
Ban ‘549 teaches an enhanced additive system for improving wet-end drainage and ash retention in papermaking using ionic crosslinked polymeric microparticles (see ¶ 0006). In particular, a coagulant, organic flocculant, or both, can be added to the pulp, as sequentially, simultaneously, or as a blend with the polymeric microparticles. The coagulant can be a cationic coagulant component, which can be or include a cationic organic polymer coagulant, an inorganic cationic coagulant, or combinations thereof. Cationic organic polymer coagulants can be, for example, glyoxylated cationic polyacrylamide (which reads on the claimed dialdehyde-modified polyacrylamide copolymer), copolymer of vinylamine and acrylamide (which reads on the claimed polyacrylamide copolymer), or any combinations thereof. Inorganic cationic coagulants which can be used can be, or include, inorganic cationic chemicals, e.g., aluminum sulfate (alum), polyaluminum chloride (PAC) and polyaluminum sulfate (PAS) (¶ 0042), each of which reads on the claimed polyaluminum salt.
Jehn-Rendu teaches a process for the production of paper, board and cardboard having high dry strength comprising the addition of (a) at least one trivalent cation in the form of a salt, (b) at least one water-soluble cationic polymer and (c) at least one water-soluble amphoteric polymer to the paper stock (see Abstract and claim 1). Examples of trivalent cation salt that may be used are polyaluminum chloride, aluminum sulfate or aluminum lactate (see ¶¶ 0035-0036).
Krapsch teaches that strength polymers (also referred to as strength resins, strength aids, strength additives and the like) are extensively utilized in paper manufacture. It is often distinguished between dry strength polymers and wet strength polymers, though dry strength polymers often impart a certain degree of wet strength to the paper, and vice versa. Today, the most common types of synthetic dry and/or wet strength polymers are based on polyvinylamine or polyacrylamide. (See ¶ 0004).
Krapsch’s paper-making process includes adding a dry and/or wet strength polymer to the cellulosic material (see ¶ 0023). Krapsch further teaches that a retention aid, such as polyaluminum chloride, polyaluminum sulfate, etc., may be used in combination with the dry and/or wet strength polymer (see ¶¶ 0304-0311).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have included a polyaluminum salt, such as polyaluminum chloride or polyaluminum sulfate, etc., in Zhu’s papermaking composition containing strengthening aids because Zhu teaches that the papermaking composition can contain other chemical aids for paper making, and it is well known in the art to include polyaluminum chloride, polyaluminum sulfate, etc., in such composition so as to take advantage of their known intended functions as coagulants, providing strength, and as retention aids, as taught by Ban ‘549, Jehn-Rendu and Krapsch.
With respect to claim 22, Zhu’s Example 2 (¶¶ 00144-00145) uses a 1:1 weight ratio of dialdehyde-modified polyacrylamide copolymer, i.e., GPAM copolymer solution 1, and amphoteric polyacrylamide copolymer 1, which each have a molecular weight of 1.2 million Daltons (see ¶¶ 00116 and 00133-00134). Thus, Zhu’s Example 2 has a molar ratio of 50:50, as here claimed.
With respect to claim 25, Zhu teaches that the cationic polyacrylamide copolymer can comprises from 0.1-50 mol%, such as 1-20 mol%, of cationic monomer (see ¶ 0037).
With respect to claim 26, Zhu teaches that the paper-making composition has a pH value of 6.0 or above, e.g., 6.5-13.0, e.g., 7.0-12.0, e.g., 7.5-11.0, e.g., 8.0-10.0 (see ¶ 0048), each of which overlaps and thus, renders obvious the claimed pH range of about 6 to about 9. See MPEP 2144.05.I. In fact, the compositions in Zhu’s Examples 1, 2, 4, 5 and 6 have a respective pH of 6.8, 7.5. 7.8, 8.5 and 8.1, as here claimed (see ¶¶ 00142, 00145, 00149, 00151, and 00153).
With respect to claim 27, Zhu teaches that the composition is added to into a pulp slurry, i.e., instant paper sheet precursor (see ¶ 0068).
With respect to claim 28, Zhu teaches that the paper-making composition can be in the form of a solution or a dispersion, and is added to pulp forming a suspension (see ¶¶ 0066, 0075 and 0078).
Claim 21 is rejected under 35 U.S.C. 103 as being unpatentable over Zhu in view of Ban ‘549, Jehn-Rendu and Krapsch as applied to claims 19-20 and 22-28 above, and further in view of Dulko.
Zhu in view of Ban ‘549, Jehn-Rendu and Krapsch, as relied upon for the reasons stated above in Rejection No. 4, differs from claim 21 in that they do not specifically teach that the polyaluminum salt has a basicity of from about 40% to 83%.
Dulko is relied upon for the reasons stated above in Rejection No. 3.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used Dulko’s polyaluminum salt having a basicity of, e.g., 83% or 50%, as the polyaluminum salt coagulant in the papermaking composition of Zhu in view of Ban ‘549, Jehn-Rendu because Dulko teaches that its polyaluminum salt, i.e., polyaluminum chlorides or polyaluminum chlorosulfates can be used in the production of paper, and because the polyaluminum chlorides or polyaluminum chlorosulfates can be produced for large scale industrial applications, as taught by Dulko.
Response to Arguments
Applicant's arguments filed December 4, 2025 have been fully considered but they are not persuasive.
Arguments with respect to the recapture rejection of claims 19-28 are rejected under 35 U.S.C. 251:
Applicant argues that claims 19-28 are directed to an overlooked aspect, and, as per MPEP 1412.01.III, are not subject to recapture (Remarks, p. 9). In particular, Applicant further argues the following on p. 9 of the Remarks:
Independent claim 19 (and dependent claims 20-28 therefrom) is directed to a composition, while the claims presented in the original application are directed to a method. Therefore, the composition claims 19-28 are drawn to a separate invention or separate aspect/embodiment/species not covered by a claim (e.g., a generic claim) at any point during the prosecution of the original application. Additionally, a restriction requirement or election of species was not issued during prosecution of the original application.
This argument is unpersuasive. As noted in MPEP 1412.01.III, overlooked aspects are distinct elements that were never claimed and thus, never surrendered. MPEP 1412.01.II further notes that if the original claim covered the subject matter of the reissue claim, then the reissue claim is not directed to an overlooked aspect.
Claims 1 and 18 filed 11/30/2024 in the ‘967 application are original claims that stated the following:
PNG
media_image8.png
168
628
media_image8.png
Greyscale
PNG
media_image9.png
86
634
media_image9.png
Greyscale
The composition in the method of original claims 1 and 18 is a combination of a polyaluminum salt and a strengthening agent comprising a dialdehyde-modified polyacrylamide copolymer and a polyacrylamide copolymer. This composition covers, i.e. encompasses, the composition in reissue claims 19-28. Thus, the composition in reissue claims 19-28 is not a “distinct element” that was never claimed. Rather, it was a composition element within the original method claims. Thus, the recapture rejection is maintained.
Arguments with respect to the rejection of claims 1-3, 5, 7, 9-11, 14, 16, 17, 19, 20 and 22-28 over Yoshioka in combination with Zhu, and the rejection of claims 13 and 21 over Yoshioka and Zhu further in view of Dulko:
Applicant cites the experimental results in Tables 1 and 2, i.e., from Examples 1 and 2, of the ‘391 patent and argues unexpected results (Remarks pp. 10-11):
Independent claims 1 and 19 are patentable over the cited references for at least the reason that the claimed method and composition results in unexpectedly improved paper strength. Example 1 describes experiments measuring Scott bond and ash content of handsheets prepared according to the claimed method compared to handsheets prepared with strengthening agents but without an aluminum salt. Figure 1 shows that paper strength aids comprising a strengthening agent and a polyaluminum salt outperformed the control paper strength aid without a polyaluminum salt in Scott bond and ash content. The improvement was observed at both dosages of 7.5 kg/ton and 15 kg/ton.
The turbidity and dewatering efficiency of the paper strength aid composition and aluminum salt was studied, and Figure 2 shows that the claimed method results in superior turbidity and dewatering efficiency compared to using a strengthening agent without a polyaluminum salt.
As conceded by the Office Action, Yoshioka fails to disclose treating the paper with a cationic dialdehyde-modified polyacrylamide copolymer. To cure the deficiency, the rejection relies on Zhu for allegedly teaching a cationic dialdehyde-modified polyacrylamide copolymer. However, all the cited references fail to teach or suggest that the claimed method and composition would produce an improvement in ash content and dewatering efficiency. For example, Yoshioka mentions that other papermaking additives can be used but does not teach that combining an aluminum salt with the claimed strength aid would lead to the results shown in Figures 1 and 2.
Applicant’s arguments and the experimental results in Figs. 1 and 2 from Example 1 and 2 of the ‘391 patent are unpersuasive. In particular, the comparative experiments are not fairly representative of the closest prior art, i.e., Yoshioka, and the results are expected, not unexpected.
The “control” paper strength aid in Examples 1 and 2 of the ‘391 patent consisted of a 50:50 mixture of cationic dialdehyde-modified polyacrylamide strength aid (Nalco 63660) and amphoteric polyacrylamide strength aid (Nalco 63600) (see col. 16, lines 27-60). The control did not contain polyaluminum salt (see col. 16, lines 34-60). The inventive examples further added polyaluminum salt, i.e., polyaluminum chloride (PAC) to said straightening agent (see col. 16, lines 40-60 and Figs. 1 and 2).
However, since the control (comparative) experiment did not contain polyaluminum salt, it is not representative of Yoshioka, which specifically teaches a synergistic effect of the combination of an amphoteric acrylamide-based polymer component and at least one aluminum compound selected from the group consisting of alumina sol, polyaluminum chloride and polyaluminum hydroxide (see the fifth and eighth pages). For example, Yoshioka’s Example 2 uses 0.4%, i.e., 3.6 kg/ton, of amphoteric polyacrylamide copolymer in combination with polyaluminum chloride at 0.1% or 0.12%. i.e., 0.9 kg/ton or 1.8 kg/ton, respectively (see Yoshioka’s Table 2).
According to the ‘391 patent specification, the properties measured in Examples 1 and 2 of the ‘391 patent, i.e., bond and ash content (Fig. 1 of the ‘391 patent) and turbidity and dewatering (Fig. 2 of the ‘391 patent) are paper strength properties (see col. 16, lines 8-15). However, Yoshioka teaches that the synergistic combination of amphoteric polyacrylamide polymer with either polyaluminum chloride or polyaluminum hydroxide significantly improves the paper strength (eighth page of Yoshioka, emphasis added):
The inventors have not fully elucidated the mechanism of the interaction between the amphoteric acrylamide polymer component and the aluminum compound component added to the raw material pulp slurry of the present invention. However, when comparing the use of each of them alone with the use of both in combination, the latter shows a tremendous synergistic effect, so there is no doubt that there is an interaction between the two, and itis currently speculated as follows. Alumina sol used in the present invention. The aluminum compound component selected from the group consisting of polyaluminum chloride and polyaluminum hydroxide both contain highly positively charged polymeric polynuclear condensed ions as active ingredients, so that they are adsorbed and strongly bonded to the surface of the filler particles, and also firmly bonded to the anionic groups of the amphoteric acrylamide polymer component. On the other hand, the amphoteric acrylamide polymer component is efficiently fixed to the pulp fiber by the action of the cationic group. Therefore, itis considered that the coexistence of both the amphoteric acrylamide polymer component and the specific aluminum compound component makes the bond between the pulp fiber and the material very strong through the organic-inorganic complex farmed by the two components, and this bond is formed very efficiently. It is also presumed that the polyvalent cations of the aluminum compound component form effective cross-linking bonds between the amphoteric acrylamide polymer molecules due to their high molecular weight, which further significantly improves the excellent paper strength enhancing effect of the acrylamide polymer, thereby realizing the astonishing paper strength enhancing effect and yield improvement effect of the present invention.
Thus, the fact that Figs. 1 and 2 of the ‘391 patent showed improved paper strength properties when polyaluminum chloride was added to a strength agent which contained amphoteric polyacrylamide copolymer, as per Yoshioka, is expected based on Yoshioka’s teachings.
To any extent unexpected results are shown in Figs. 1 and 2 of the ‘391 patent (it is maintained that none have been shown), at least claim 19 and its dependent claims are not commensurate in scope with respect to the specific dialdehyde-modified polyacrylamide copolymer and polyacrylamide copolymer that were used, their molar ratio, and the respective amounts per ton of dry fibers of the polyaluminum salt and strengthening agent.
Applicant further argues (Remarks, p. 11):
Even if one of ordinary skill in the art would have sought to combine the teachings of Yoshioka and Zhu, it is asserted that a person of ordinary skill in the art would not have been motivated to modify Yoshioka to further include any additional polymer, such as a dialdehyde-modified polyacrylamide copolymer of Zhu. Moreover, it is asserted that a person of ordinary skill in the art would not have been motivated to modify Zhu to further include an aluminum salt of Yoshioka.
These arguments are unpersuasive since there is rationale for combining Yoshioka and Zhu. As noted above in Rejection No. 2, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have further included a cationic dialdehyde-modified polyacrylamide copolymer in Yoshioka’s pulp treatment that already uses a combination of an amphoteric polyacrylamide copolymer and an aluminum compound because Yoshioka specifically teaches that the treatment does not preclude the use of other paper-making additives, and the use of a combination of a dialdehyde-modified polyacrylamide and a polyacrylamide, e.g., an amphoteric polyacrylamide copolymer, provides the advantages of substantially increased ash retention and/or increased strength of the paper, as taught by Zhu.
Alternatively, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have included Yoshioka’s aluminum compound, such as polyaluminum chloride or polyaluminum hydroxide, in Zhu’s paper-making composition because Zhu specifically teaches that other chemical aids can be contained in the composition, and so as to take advantage of the fact that the combination of an amphoteric polyacrylamide copolymer (already present in Zhu’s composition) and an aluminum compound provides for a synergistic effect, improves filler retention and provides for an excellent paper strength-enhancing effect, as taught by Yoshioka. Indeed, Zhu teaches use of fillers (see ¶¶ 0075 and 0083).
Arguments with respect to the rejection of claims 19-20 and 22-28 over Zhu in view of Ban ‘549, Jehn-Rendu and Krapsch, and the rejection of claims 13 and 21 further in view of Dulko:
Applicant argues that “amended independent claim 19 is patentable over the cited references for at least the reason that the claimed composition results in unexpectedly improved paper strength.” (Remarks, p. 12).
This argument is unpersuasive for the same reasons set forth above with respect to the combination of Yoshioka and Zhu. Applicant’s comparative examples are not fairly representative of the prior art, and the improved paper strength results are expected based on the known synergistic effect in the art when using a combination of polyaluminum chloride and an amphoteric polyacrylamide polymer. Further, as also noted above, to the extent anything unexpected has been shown (it is again maintained that no unexpected results are shown), claim 19 and its dependent claims are not commensurate in scope with respect to the specific dialdehyde-modified polyacrylamide copolymer and polyacrylamide copolymer that were used, their molar ratio, and the respective amounts per ton of dry fibers of the polyaluminum salt and strengthening agent.
Applicant further argues that “it is not clear that one of ordinary skill in the art would combine an aluminum salt with a dialdehyde-modified polyacrylamide copolymer and a polyacrylamide copolymer” and that “Zhu provides no teaching or suggestion to include any particular optional additive, such as an inorganic salt like a polyaluminum salt.” (Remarks, pp. 12-13).
These arguments are unpersuasive. Zhu teaches that the papermaking composition can contain chemical aids, i.e., additives, for paper making (see ¶ 0046). The rationale for modifying Zhu with Zhu in view of Ban ‘549, Jehn-Rendu and Krapsch is set forth above in Rejection No. 4 and reproduced below:
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have included a polyaluminum salt, such as polyaluminum chloride or polyaluminum sulfate, etc., in Zhu’s papermaking composition containing strengthening aids because Zhu teaches that the papermaking composition can contain other chemical aids for paper making, and it is well known in the art to include polyaluminum chloride, polyaluminum sulfate, etc., in such composition so as to take advantage of their known intended functions as coagulants, providing strength, and as retention aids, as taught by Ban ‘549, Jehn-Rendu and Krapsch.
Duty to Disclose
Applicant is reminded of the continuing obligation under 37 CFR 1.178(b), to timely apprise the Office of any prior or concurrent proceed-ing in which Patent No. 10,982,391 is or was involved. These proceedings would include interferences, reissues, reexaminations, and litigation. Applicant is further reminded of the continuing obligation under 37 CFR 1.56, to timely apprise the Office of any information which is mate-rial to patentability of the claims under consideration in this reissue appli-cation. These obligations rest with each individual associated with the filing and prosecution of this application for reissue. See also MPEP §§ 1404, 1442.01 and 1442.04.
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.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALAN D DIAMOND whose telephone number is (571)272-1338. The examiner can normally be reached Monday through Thursday 5:30 am to 3:00 pm, and Fridays from 5:30 am to 9:30 am.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Patricia Engle can be reached on 571-272-6660. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
Signed:
/ALAN D DIAMOND/Patent Reexamination Specialist
Central Reexamination Unit 3991
Conferees:
/JOSEPH R KOSACK/ /Patricia L Engle/Patent Reexamination Specialist SPRS, Art Unit 3991
Central Reexamination Unit 3991