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 Amendment
In response to the amendment received 3/30/2026:
Claims 1, 4, 6-10, and 12-20 are presently pending
Claims 12-20 are withdrawn
Claims 2-3, 5, and 11 are cancelled
The objections to the specification are withdrawn in light of the amendments
The claim previously stated rejections under 35 U.S.C. 112(b) are withdrawn in light of amendments to the claims
All prior art grounds of rejection are maintained, with new grounds only as necessitated by amendment
Claim Interpretation
It is noted that claim 1 is drafted using both open and closed connecting terms: “comprising isolating cellulose nanocrystals from a feedstock . . . isolating the cellulose nanocrystals consists of . . . extracting cellulose from the feedstock consists of . . . extracting cellulose nanocrystals from the cellulose comprises . . .” [emphasis added]. When the phrase “consisting of” appears in a clause of the body of a claim, rather than immediately following the preamble, there is an “exceptionally strong presumption that a claim term set off with ‘consisting of’ is closed to unrecited elements.” Multilayer Stretch Cling Film Holdings, Inc. v. Berry Plastics Corp., 831 F.3d 1350, 1359, 119 USPQ2d 1773, 1781 (Fed. Cir. 2016). However, the claimed method taken as a whole utilizes the transitional term “comprising,” which is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. See MPEP 2111.03. As such, because the claimed method taken as a whole uses the transitional term “comprising” (line 1 of claim 1), additional unrecited steps are regarded as permitted.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 4 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claim 4, the recitation “wherein the enzymatic hydrolysis uses cellulolytic enzymes from Trichoderma reesei” renders the claim indefinite. The recitation is indefinite because it is unclear which alternative enzymatic hydrolysis step in claim 1 the recitation refers back to: The enzymatic hydrolysis in the “extracting cellulose” step or that in the “extracting nanocrystals” step or both. For purposes of examination, any use of Trichoderma reesei in either of these or both of these steps is regarded as reading on this limitation. It is also noted that the enzymatic hydrolysis is an optional alternative, so prior art which teaches one of the other isolation methods in claim 1 is regarded as reading on a further limitation of the optional alternative.
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.
Claim(s) 1, 4, 7, and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Ng (U.S. Patent Pub. No. 2023/0148495 A1, hereinafter “Ng”) in view of “Extraction of cellulose nanocrystals from plant sources for application as reinforcing agent in polymers,” Sin et al, Composites Part B, 14 January 2015 (hereinafter “Sin”).
Regarding claim 1, Ng teaches a method of making a plant growth medium (e.g., a method of forming a keratin-based growth medium substrate for plants) [Abstract] comprising isolating cellulose nanocrystals from a feedstock and adding the cellulose nanocrystals to a germination material to generate the plant growth medium (e.g., adding a natural biopolymer such as cellulose nanocrystals to a keratin-based substrate for supporting seed germination and plant growth) [Abstract & 0002 & Para. 0054-55],
Wherein isolating the cellulose nanocrystals consists of:
Extracting cellulose from the feedstock (the natural biopolymer is obtained from a plant material such as cotton, wood, pulp, vegetable trimmings, etc. by chemical and physical methods, here regarded as reading on isolation from a feedstock) [Para. 0058] and extracting the cellulose nanocrystals from the cellulose (e.g., the nanocellulose may be modified, and selected from the group consisting of cellulose nanocrystals, modified cellulose nanocrystals, etc.) [Para. 0055].
Ng does not explicitly disclose (1) a method of extraction of cellulose being enzymatic hydrolysis, cryocrushing, high shear grinding, or a mixture thereof, (2) a method of extracting cellulose nanocrystals being enzymatic hydrolysis, performing ultrasonication on the cellulose, performing high energy bead milling, or a combination thereof, or (3), the cellulose nanocrystals having an aspect ratio from 10 to 200.
As to (1) and (2), Ng teaches the method implementing cellulose nanocrystals from a feedstock such as various plant materials [Ng Para. 0058] but does not disclose a specific method of isolation of cellulose and the cellulose nanocrystals as claimed. However, Sin teaches a method of extracting cellulose nanocrystals from plant sources for use in combination with other polymers to create structural support [Sin Abstract] wherein the cellulose is subjected to several options of isolation steps including alkali treatment to expose the crystallites [Sin Page 183 Para. 3.2.1], acid hydrolysis to extract highly crystalline and purified nanocrystals [Sin Page 186 Para. 3.3], enzymes to selectively remove amorphous regions to afford highly crystalline and purified cellulose crystals [Sin Page 186 Para. 3.3], strong mechanical shearing to create uniform sizes [Sin Page 189 Para. 3.3.4] and/or ultrasonication to create a homogeneous stable suspension and further isolate the nanocrystals [Sin Page 189 Para. 3.3.4]. As such, in looking for a suitable way to implement cellulose nanocrystals isolated from plants in a polymer matrix as suggested by Ng, one of ordinary skill in the art would look to Sin and readily appreciate the advantages of a method involving extracting cellulose followed by extracting the nanocrystals, specifically implementing enzymatic hydrolysis, high shear grinding, and ultrasonication, resulting in highly crystalline and purified crystals with uniform sizes. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention in performing the method of Ng to specifically implement the isolation process taught by Sin.
As to (3), while Ng does not disclose a specific aspect ratio of the nanocrystals, Sin further teaches that high CNC aspect ratio is a desirable quality which depends on the method of isolation; for example, the time undergoing acid hydrolysis [Sin Page 188 Para. 3.3.2, paragraph bridging Col. 1-2]. Larger aspect ratios are desirable so that the CNC has a larger contact surface with the matrix where it will be used [Sin Page 180 Para. 2.2]. Aspect ratios higher than 30 have stronger reinforcement effects compared to other nanofillers, ranging up to 100 depending on the source and preparation/isolation conditions [Sin Pages 180-181, Para. 2.3]. CNCs with high aspect ratios are of particular interest because of their properties for improving composite materials: they have nano-enabled functional properties, tangling effects, and percolation effects, as well as good physical flexibility [Sin Page 181, first paragraph in Col. 1]. As such, in performing the method of Ng implementing the steps of Sin, one of ordinary skill in the art would readily arrive at the particular aspect ratio disclosed and taught to be advantageous by Sin. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention in performing the modified method of Ng to isolate cellulose nanocrystals having an aspect ratio within the range as claimed as taught by Sin.
Regarding claim 4, the enzymatic hydrolysis is recited in the alternative in claim 1, and as such Ng as modified by Sin teaching enzymatic hydrolysis or other options for isolation including high shear grinding and ultrasonication is regarded as reading on a further limitation of the alternative enzymatic hydrolysis.
Regarding claim 7, Ng teaches the method implementing cellulose nanocrystals from a feedstock such as various plant materials [Ng Para. 0058] but does not disclose a specific method of isolation resulting in any disclosed lignin or hemicellulose content. However, Sin further teaches that cellulose is generally found in nature in combination with lignin and hemicellulose, and these fibers need to be removed to obtain highly purified cellulose fibers and CNCs [Sin Page 183 Para. 3.2]. Hemicellulose and lignin are undesirable because they reduce the crystallinity ratio, thermal stability, and mechanical performance of the cellulose. Various purification techniques serve to isolate the cellulose and remove the lignin and hemicellulose, such as alkali pulping and bleaching [Sin Page 183 Para. 3.2] As such, in looking for a suitable way to implement cellulose nanocrystals isolated from plants as suggested by Ng, one of ordinary skill in the art would look to Sin and readily appreciate that it is standard and even advantageous to implement a method which necessarily removes the lignin and hemicellulose from the nanocrystals, and would know how to do so via the teachings of Sin. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention in performing the modified method of Ng to specifically implement a method which necessarily removes lignin and hemicellulose as taught by Sin.
Regarding claim 10, Ng as modified by Sin teaches the method wherein the plant growth medium comprises a plant seed (e.g., the substrate is for supporting seed germination [Para. 0043]; see also Fig. 12A and 12B showing plant growth assessment of Arabidopsis seeds in the substrate [Para. 0043]).
Claim(s) 6 and 8-9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ng and Sin as applied to claim 1 above, and further in view of Zhang (U.S. Patent Pub. No. 2019/0330378 A1, hereinafter “Zhang”).
Regarding claim 6, Ng as modified by Sin teaches the method implementing cellulose nanocrystals from a feedstock such as various plant materials [Ng Para. 0058] which can result in rod-like crystals depending on the isolation method [Sin Page 188 Para. 3.3.2] but does not explicitly teach the shape of the nanocrystals being rod-shaped and/or spherical. However, Zhang teaches that standard cellulose nanocrystals are either spherical or rod/needle-shaped, depending on their method of preparation and isolation [Zhang Para. 0003]. As such, in looking for suitable and available shapes of cellulose nanocrystals, one of ordinary skill in the art would look to Zhang and readily appreciate that spherical and rod-shaped are the standard options. Selecting spherical or rod-shaped nanocrystals amounts to no more than choosing from a finite number of identified, predictable solutions, with reasonable expectation of success, as these are the two standard shapes for cellulose nanocrystals. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention in performing the method of Ng as modified by Sin to implement spherical or rod-shaped cellulose nanocrystals as taught by Zhang.
Regarding claim 8, Ng as modified by Sin teaches the method implementing cellulose nanocrystals from a feedstock such as various plant materials [Ng Para. 0058] but does not explicitly teach the size or width of the nanocrystals. However, Zhang teaches that standard cellulose nanocrystals typically have a diameter from 50 nm to 200 nm, or a width greater than 10 nm and a length greater than 200 nm, or a width of 5 to 10 nm and a length greater than 100 nm, depending on their method of preparation and isolation [Zhang Para. 0003]. As such, in looking for suitable and available sizes of cellulose nanocrystals, one of ordinary skill in the art would look to Zhang and readily appreciate that widths which overlap with the claimed range are the standard options. Selecting these particular sizes amounts to no more than choosing from a finite number of identified, predictable solutions, with reasonable expectation of success, as these are the standard sizes available for cellulose nanocrystals. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention in performing the method of Ng as modified by Sin to isolate cellulose nanocrystals having a width from 3 nm to 100 nm as taught by Zhang.
Regarding claim 9, Ng as modified by Sin teaches the method implementing cellulose nanocrystals from a feedstock such as various plant materials [Ng Para. 0058] but does not explicitly teach the size or length of the nanocrystals. However, Zhang teaches that standard cellulose nanocrystals typically have a diameter from 50 nm to 200 nm, or a width greater than 10 nm and a length greater than 200 nm, or a width of 5 to 10 nm and a length greater than 100 nm, depending on their method of preparation and isolation [Zhang Para. 0003]. As such, in looking for suitable and available sizes of cellulose nanocrystals, one of ordinary skill in the art would look to Zhang and readily appreciate that lengths which overlap with the claimed range are the standard options. Selecting these particular sizes amounts to no more than choosing from a finite number of identified, predictable solutions, with reasonable expectation of success, as these are the standard sizes available for cellulose nanocrystals. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention in performing the method of Ng as modified by Sin to isolate cellulose nanocrystals having a length from 50 nm to 6 um as taught by Zhang.
Response to Arguments
Applicant's arguments filed 3/30/2026 have been fully considered but they are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
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.
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/H.E.R./Examiner, Art Unit 1731
/AMBER R ORLANDO/Supervisory Patent Examiner, Art Unit 1731
