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 .
Claims 1-15, 18, 21-24 are pending and are under examination on the merits.
No claims are amended.
Claims 16, 19-20 are previously canceled.
No claims are newly added.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 10/22/25 has been entered.
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.
The rejection in the previous action of claims 1-15, 18, 21-24 under 35 U.S.C. 103 as being unpatentable over Klaus-Nietrost et al (US PG Pub 2020/0347520 A1) is withdrawn in view of further search and consideration. It is not clear that Klaus-Nietrosts recitation of “acid” in paragraph 31 meets the instant claim 1 pH of less than 5 in step (v).
Claim(s) 1-8, 10-15, 18, 22-24 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 20200165747 by Lindgren et al in view of WO 2021181007 represented herein by US 20230132641 by Harlin et al.
Lindgren describes recycling of textile materials.
Regarding claim 1, Lindgren describes a method of recycling cellulose for textile fiber feedstock (paragraph 15, 19 “can be used in a process for production of viscose” reads on “for textile fiber feedstock”).
Lindgren describes:
(i) providing a cellulose-based textile feedstock (step (a) paragraph 16)
(ii) shredding the waste textile feedstock (paragraph 36 “shredder before step (b)”). Lindgren states that the shredding creates a larger surface of the material so that subsequent steps are facilitated but is silent as to the size achieved (paragraph 36). The instantly claimed shredded size is met via secondary reference Harlin below.
(iii) mixing the shredded textile with an aqueous alkali solution (paragraph 37, step (b)). This achieves a pH of 9-13.5, or optionally 11-13.3 (paragraph 37). Alternatively, Lindgren’s description of step c)i) (paragraph 32) also reads on mixing the shredded textile with an aqueous alkali solution, achieving a pH of 9-13.5.
(iv) filtering the first mixture to obtain an alkali treated waste textile feedstock (“dewatered…before step c)ii)” paragraph 43)
(v) mixing the alkali treated shredded waste textile feedstock with an aqueous acid (paragraph 33, 43), achieving a pH of 1.5-5 (paragraph 43).
(vi) filtering the second mixture to obtain cellulose (paragraph 44 recovered; parargraph 55 “hand squeezed”)
Regarding the final passage of claim 1 after the roman numeral steps, the source of the alkali solution or the acid solution is not recited as an active step. The instant claim language is product-by-process language within a process claim. “[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985). Thus since Lindgren’s recited alkali and acid aqueous solutions are capable of being obtained from the manufacture of paper pulp during bleaching stages or viscose processing, they meet this aspect of the claim.
Harlin describes separation of polycotton blends.
Harlin states that an ideal shredding size is for example 1 to 5 mm in length (paragraph 26). Harlin states that this size provides fibers with surface areas optimal for contacting with liquids. Thus one of ordinary skill would be motivated to use the shredded cotton fiber size of 1-5 mm where Lindgren is silent because Harlin describes it as ideal for contacting with liquids.
Regarding claim 2, Lindgren describes samples which are almost entirely cotton (paragraph 26, 35), i.e. a large majority cellulose. This reads on the claimed range.
Regarding claims 3 and 4, Lindgren describes the possibility of “different types of textiles as long as at least part of the textiles comprise cellulose” (paragraph 35) but is silent as to the chemical makeup of these textiles.
Both Harlin and Lindgren describe the alkali treatment of cotton (cellulose)-based materials at elevated temperature (Harlin paragraph 22, Lindgren paragraph 38 and 41). Harlin state that this treatment can also remove polyester fibers (paragraph 22). Thus it would be obvious to one of ordinary skill to use a cellulose-based starting material which contains up to 30 wt% polyester (Harlin paragraph 22, 19) where Lindgren more broadly describes materials which “comprise cellulose” because the alkali treatment described in Lindgren is capable of removing the polyester fibers.
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990), In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997). It would be obvious to one of ordinary skill to arrive at values in the claimed range because Harlin describes values overlapping with the claimed range.
Regarding claim 5, Harlin’s description of 1-5 mm meets the term “comprises fibers which have a fibre length of less than 3 mm” as well as “comprises fibres which have a fibre length of at least 1 mm”.
Regarding claim 6, Lindgren describes alkali solutions with pH up to 13.5 (paragraph 32, 37). In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990), In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997). It would be obvious to one of ordinary skill to arrive at values in the claimed range because Lindgren describes values overlapping with the claimed range.
Regarding claim 7, Lindgren describes acid solutions with pH of 1.5-5 (paragraph 43).
Regarding claim 8, Lindgren describes sodium hydroxide (paragraph 37).
Regarding claim 10, Lindgren describes mixing temperature of step b) as 50-100C (paragraph 38) and step c)i) as 60-120C (paragraph 41).
Regarding claim 11, Lindgren describes step c)i) as 20 min-24 hrs, or 30-120 min in an embodiment (paragraph 42).
Regarding claim 12, Lindgren exemplifies acid treatment for 30 minutes at room temperature (paragraph 55).
Regarding claim 13, Lindgren describes ozone, an oxidant, present in acid treatment (paragraph 16 step c)ii)).
Regarding claim 14, Lindgren describes washing the cellulose after the alkali treatment and before the acid treatment (paragraph 43).
Regarding claim 15, Lindgren describes a washed product cellulose (paragraph 55).
Regarding claim 18, Lindgren describes a using the recycled material in a process for production of viscose (paragraph 46), i.e. as a textile fiber feedstock.
Regarding claim 22, Lindgren describes mixing temperature of step b) as 50-100C (paragraph 38) and step c)i) as 60-120C (paragraph 41).
Regarding claim 23, Lindgren describes washing the cellulose after the alkali treatment in order to bring down the pH before acid treatment (paragraph 43). Since water has a pH of about 7 Lindgren’s wording inherently contains a minimum limit of “washed to a pH of 7”.
Regarding claim 24, Lindgren describes a washed finished sample (paragraph 55). Since the purpose of washing is to rid the cellulose of impurities, i.e. the previous acid treatment, and the pH of water is about 7, Lindgren’s description “washed” inherently contains a maximum limit of “washed to a pH of 7”.
Claims 8, 9 and 21 are rejected under 35 U.S.C. 103 as being unpatentable over US 20200165747 by Lindgren et al in view of WO 2021181007 represented herein by US 20230132641 by Harlin et al in further view of CN 103255613 by Xu et al.
Lindgren is described above.
Regarding claims 8, 9 and 21, Lindgren describes step c)i) as a bleaching step (paragraph 32), but is silent as to the chemical used to achieve the high pH or its amount, although Lindgren elsewhere describes sodium hydroxide to achieve high pH (paragraph 37).
Xu describes a bleaching method for cotton.
Xu describes a bleaching (light) method for cotton in which the alkali liquid is sodium hydroxide in an amount of 180-280 g/L (machine translation paragraph 9). Xu describes the combination of alkali with a mixed liquid of organic alcohol with water as achieving uniform penetration (paragraph 13). Thus it would be obvious to one of ordinary skill to use Xu’s specific sodium hydroxide amount with mixed aqueous solvent in order to achieve uniform penetration of the cellulose.
Regarding the concentration of sodium hydroxide claimed, In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990), In re Geisler, 116 F.3d 1465, 1469-71, 43 USPQ2d 1362, 1365-66 (Fed. Cir. 1997). It would be obvious to one of ordinary skill to arrive at values in the claimed range because Xu describes values overlapping with the claimed range.
Response to Arguments
Applicant’s argument p.3 of Remarks submitted 10/22/25 has been considered and is persuasive. Previously applied reference Klaus was deficient in addressing some claim limitations and has been withdrawn. However, it is noted that the instant claim language is to feedstock comprising fibers with a length of less than 5 mm, which is different and broader than language requiring all fibers to have an average length of less than 5 mm. New art has been applied above which addresses the fiber length claimed.
Applicant’s argument p.4-5 of Remarks has been considered and is persuasive. Previously applied reference Klaus inadequately described the specific acid/base steps recited in the instant claims. New art is applied above which addresses each claim limitation. However, applicant appears to be relying on the claim language at the end of claim 1, after the roman numerals, to be distinguishing. As noted above in rejection, this claim language does not involve active steps for the aqueous alkali solution (or acidic solution) to be obtained from paper pulp manufacture or viscose manufacture. The instant claim language is product-by-process language within a process claim. Thus art which contains aqueous alkali/acidic solutions which are capable of having been used in paper processing or viscose process still apply to this aspect of the claim.
Applicant’s argument p.6 of Remarks and Declaration filed 10/22/25 have been considered but are not persuasive. Applicant states that a surprising benefit of the instant application hinges on the effectiveness of a step that is not actively recited, the final phrase of claim 1. If indeed this aspect is key to the application, it should be claimed in a way such that it is an active step- i.e. “obtaining the aqueous alkali solution from the manufacture of viscose process”. As currently claimed, for example, any aqueous solution which could have been obtained from the manufacture of viscose process applies.
Applicant’s argument p.6 final paragraph and p.7 and Declaration have been considered but are not persuasive. Applicant states that there is a synergistic effect of smaller fibers combined with used aqueous alkali solution. This is not found convincing because the definition of synergistic effect is an effect that is greater than expected. First, it is well established that smaller fibers have greater surface area and are thus more efficiently treated by solutions (see for example Harlin paragraph 26). This is not a surprising or unexpected effect. Second, the average fiber size is not actually claimed; the claim describes fibers that must only include some fibers which have a length less than 5 mm. Third, the active step of using a used (recycled) aqueous alkali or acid solution is not claimed. These deficiencies should be addressed if further consideration of unexpected results is to be contemplated later in prosecution.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHRISTINA W ROSEBACH whose telephone number is (571)270-7154. The examiner can normally be reached 8am-3:30pm.
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, Randy Gulakowski can be reached at 5712721302. 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.
/CHRISTINA H.W. ROSEBACH/Examiner, Art Unit 1766