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 .
DETAILED ACTION
2. This Office Action is responsive to Applicant’s Amendment and Remarks, filed December 23, 2025. The amendment, filed December 23, 2025, is entered, wherein claims 1 – 2 are amended, claims 17 – 18 are new, and claims 11 – 16 are withdrawn.
Claims 1 – 18 are pending in this application and claims 1 – 10 and 17 – 18 are currently examined.
Priority
3. This application is a national stage application of PCT/EP2020/053426, filed February 11, 2020, which claims benefit of foreign priority document EP19157692.5, filed February 18, 2019. This foreign priority document is not in English.
Should applicant desire to obtain the benefit of foreign priority under 35 U.S.C. 119(a)-(d) prior to declaration of an interference, a certified English translation of the foreign application must be submitted in reply to this action. 37 CFR 41.154(b) and 41.202(e).
Failure to provide a certified translation may result in no benefit being accorded for the non-English application is pertinent only when interference arises.
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Withdrawn Rejections
4. The rejection of claims 1 – 7 and 10 in the previous Office Action, mailed September 23, 2025, under 35 U.S.C. 103 as being unpatentable over Rowell et al. in view of Chung et al. has been considered and is withdrawn in view of the amended claim 1.
The rejection of claim 8 in the previous Office Action, mailed September 23, 2025, under 35 U.S.C. 103 as being unpatentable over Rowell et al. in view of Chung et al., and further in view of Eriksen et al. has been considered and is withdrawn in view of the amended claim 1.
The rejection of claim 9 in the previous Office Action, mailed September 23, 2025, under 35 U.S.C. 103 as being unpatentable over Rowell et al. in view of Chung et al., and further in view of Nelson has been considered and is withdrawn in view of the amended claim 1.
The following are new grounds of rejection necessitated by Applicant’s Amendment and Remarks, filed December 23, 2025, wherein claims 1 – 2 are amended and claims 17 – 18 are new. Previously cited and newly cited references have been used to establish the new grounds of rejection.
Maintained Objection to Specification
5. Applicant is reminded of the proper language and format for an abstract of the disclosure.
The abstract should be in narrative form and generally limited to a single paragraph on a separate sheet within the range of 50 to 150 words in length. The abstract should describe the disclosure sufficiently to assist readers in deciding whether there is a need for consulting the full patent text for details.
The language should be clear and concise and should not repeat information given in the title. It should avoid using phrases which can be implied, such as, “The disclosure concerns,” “The disclosure defined by this invention,” “The disclosure describes,” etc. In addition, the form and legal phraseology often used in patent claims, such as “means” and “said,” should be avoided.
New 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:
i. Determining the scope and contents of the prior art.
ii. Ascertaining the differences between the prior art and the claims at issue.
iii. Resolving the level of ordinary skill in the pertinent art.
iv. 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.
Claims 1 – 7, 9 – 10, and 17 – 18 are rejected under 35 U.S.C. 103 as being unpatentable over Rowell et al. (EP0213252A1, cited in the previous Office Action) in view of Zafeiropoulos et al. (Journal of Materials Science, 2003, Vol. 38, page 3903 – 3914, Reference included with PTO-892) and Nelson (EP0799272B1, cited in the previous Office Action).
a. Regarding claims 1 – 7, 10, and 17 – 18, Rowell et al. teaches a process that is related to the chemical treatment of lignocellulosic materials by acetylation with acetic anhydride in the absence of any cosolvent or added catalyst (Col., lines 2 – 4). During the process, the partially dried or dry lignocellulosic material is impregnated with liquid acetic anhydride and drained, wherein the acetic anhydride is supplied in a proper amount (Col. 6, lines 21 – 23). The impregnated material is placed in a heated, non-pressurized chamber and kept at a temperature of 110 to 120 ⁰C for a period of time, preferably 2 to 8 hours (Col. 5, lines 3 – 4). While heated, a vacuum is applied to remove excess or unconsumed reagent and byproduct acetic acid, or the vapors produced are removed by a gasflow (Col. 4, lines 42 – 50). In example II, the components can be separated by fractional distillation and the acetic acid reconverted to acetic anhydride by reaction with ketene (Col. 10, lines 23 – 24). Rowell et al. also teaches that the lignocellulosic material used in the chemical treatment are oven-dried beforehand (Col. 8, lines 28 – 29). The acetic anhydride to softwood material ratio is about 1.0 w/w (Col. 9, lines 27 – 28). Moreover, the vapor of acetic anhydride and acetic acid produced during heating can be removed by a gasflow through the reactor or by pulling a vacuum, and the chemicals are recovered by condensation, preferably recovered and up-graded by fractional condensation in a distillation tower (Col. 7, lines 27 – 33).
However, Rowell et al. do not teach that the lignocellulosic fibrous material is not wood or a fibrous material derived therefrom, and wherein the lignocellulosic fibrous material does not include jute fibers. Rowell et al. do not teach that the method for the acetylation of lignocellulosic fibrous materials will produce an acetylated lignocellulosic fibrous material having an acetyl value in the range of from approximately 22% to 45% and a degree of substitution (DS) in the range of 0.7 to 1.5. Rowell et al. do not teach that the step of distillatively separating the acetic acid occurs simultaneously with the step of treating the lignocellulosic fibrous material.
Zafeiropoulos et al. perform fiber treatment on six different types of flax fibers (page 3904, Right Col., para. 3). The treatment is acetylation, wherein the acetylation is performed following Rowell’s method. The fibers are first “overdried”, that is until no further loss of weight for 24 h at 105 ⁰C. The fibers are then placed in a stainless steel mesh container and dipped into a beaker containing acetic anhydride for 1 min. Afterwards, the fibers are drained for 3 min and placed in a preheated (120 ⁰C) oven for two hours (page 3904, Right Col., para. 5).
Nelson also teaches a process for the production of acetylated lignocellulosic fibers wherein the lignocellulosic fiber is treated with acetic anhydride to improve the physical characteristics of the lignocellulosic fiber (para. [0001 and 0003]). The lignocellulosic fiber is a material in any shape or form, and which is derivable from a source comprising wood, sisal, jute, coconut, and/or other plant material (para. [0002]). Nelson identifies that one of the problems with systems which use the immersion technique is that they are usually batch processes which need drainage facilities for the liquid in which the lignocellulosic fiber is immersed. A single step process of this type also does not ensure acetylation of the lignocellulosic material to the desired degree nor the removal of all of the unreacted chemicals in the treated product. Nelson find that the above problems can be mitigated by treating the lignocellulosic fiber with a vaporous acetylating agent in a single state in a continuous process (para. [0003 – 0004]). The process disclosed by Nelson provides an easier and quicker process for acetylation of lignocellulosic fibers while maintaining the necessary degree of acetylation (para. [0007]). The acetylating agent is preheated to a temperature from 160 – 195 ⁰C and the acetylation reactor is suitably operated at a pressure of 100 – 150 kPa (para. [0010]). Nelson teaches the flow rate of the acetic anhydride is approximately 19 g per gram of fiber per minute at atmospheric pressure to (page 3, para. [0021]). Nelson teaches that the lignocellulosic fibers moistened with acetic anhydride and emergent from the chamber (2) is then fed to the acetylation reaction (3), also previously purged with nitrogen to exclude any air or oxygen therein, where it brought into contact with superheated vapor of an acetylating agent containing neat acetic anhydride introduced at (4) (page 3, para. [0019], lines 31 – 34). Finally, Nelson teaches that the overheads from the cyclone is recirculated back to the reactor to processing and recovering of acetic acid formed as by-product in the acetylation step (page 3, para. [0019], lines 40 – 41). The schematic flow diagram of the invention is shown below (page 7):
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Furthermore, the precise duration of the acetylation reaction of the lignocellulosic fiber in the reactor will be determined by the degree of acetylation desired and the nature and amount of the acetylatable material present in the lignocellulosic fiber. Thus, the degree of acetylation is suitably such that the acetylated lignocellulosic fiber achieves a weight gain of at least 2%, and more preferably from 5 – 30% by weight (para. [0014]).
It would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the claimed invention to substitute the wood lignocellulosic fibrous material as taught by Rowell et al. with flax fiber in view of Zafeiropoulos et al. because Rowell et al. teach the acetylation with acetic anhydride with no catalyst, non-pressurized, and about 120 ⁰C conditions and Zafeiropoulos et al. teach acetylation of flax using Rowell’s method, which is the method that is invented by the same inventors. One would have been motivated to substitute the wood lignocellulosic fibrous material as taught by Rowell et al. with flax fiber in view of Zafeiropoulos et al. because Zafeiropoulos et al. already taught using Rowell’s method for treating flax fibers, thereby yielding predictable results. One of ordinary skill in the art would have had a reasonable expectation of success to substitute the wood lignocellulosic fibrous material as taught by Rowell et al. with flax fiber in view of Zafeiropoulos et al. because Rowell et al. teach a complete acetylation reaction for lignocellulosic fibrous material, which is non-pressurized and without catalyst, and Zafeiropoulos et al. disclose the use of the same method for acetylating flax fiber.
It would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the claimed invention to modify the process of acetylation of lignocellulosic materials for acetylating flax as taught by Rowell et al. and Zafeiropoulos et al. into a continuous process in view of Nelson to obtain acetylated lignocellulosic fibrous material having an acetyl value in the range of from approximately 22% to 45% and a degree of substitution in the range of 0.7 to 1.5 because Rowell et al. and Zafeiropoulos et al. teach that a catalyst-free, non-pressurized conditions is capable of acetylating flax fibers and Nelson teaches that a continuous process will ensure acetylation of the lignocellulosic material to the desired degree. One would have been motivated to modify the process of acetylation of lignocellulosic materials for acetylating flax as taught by Rowell et al. and Zafeiropoulos et al. into a continuous process in view of Nelson to obtain acetylated lignocellulosic fibrous material having an acetyl value in the range of from approximately 22% to 45% and a degree of substitution in the range of 0.7 to 1.5 because the modification for a continuous process ensures acetylation of the lignocellulosic material to the desired degree and the desired degree of acetylation of lignocellulosic material will be obtained by adjusting the duration of the acetylation reaction. Based on the maximum weight gain disclosed by Nelson, the approximate acetyl value and DS are 23.8% and 1.16, respectively. A skilled artisan would have performed routine experimentation to discover the best duration of the acetylation reaction for the optimal acetyl value and degree of substitution. For the pressure and temperature conditions applied in the method for drying, one would have performed a routine experimentation to discover the best pressure and temperature in oven for optimal drying characteristics. For the weight ratio of acetic anhydride to lignocellulosic fibrous material, Rowell et al. teaches that a proper amount of acetic anhydride is used and Nelson explicitly teaches the flow rate of anhydride is approximately 19 g per gram of fiber per minute at atmospheric pressure. Based on this disclosure, a skilled artisan would also performed a routine experimentation to discover the best amount of acetic anhydride to be used for optimal acetylation. Therefore, one of skill in the art would have a reasonable expectation of success to modify the process of acetylation of lignocellulosic materials for acetylating flax as taught by Rowell et al. and Zafeiropoulos et al. into a continuous process in view of Nelson to obtain acetylated lignocellulosic fibrous material having an acetyl value in the range of from approximately 22% to 45% and a degree of substitution in the range of 0.7 to 1.5 because such modification is known in the art to solve problems including obtaining the lignocellulosic material with the desired degree of acetylation and Nelson explicitly teaches that the degree of acetylation may be adjusted by changing the duration of the acetylation reaction.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Rowell et al. (EP0213252A1, cited in the previous Office Action) in view of Zafeiropoulos et al. (Journal of Materials Science, 2003, Vol. 38, page 3903 – 3914, Reference included with PTO-892) and Nelson (EP0799272B1, cited in the previous Office Action) as applied to claims 1 – 7, 9 – 10, and 17 – 18 above, and further in view of Eriksen et al. (US9091022B2, cited in the previous Office Action).
b. Regarding claim 8, the references teach the limitations discussed above. Rowell et al. further teaches that the excess of acetic anhydride is just drained from the impregnation vessel in the simplest application (Col. 6, lines 57 – 58). For lignocellulosic material with a smaller size, the removal of anhydride, kept by the material by surface tension can be facilitated by applying suction allowing the anhydride to be drained through a perforated device supporting the impregnated material (Col. 7, lines 1 – 6). Zafeiropoulos et al. teach that the fibers are placed in a vacuum (0.003 MPa) for 2 h at 120 ⁰C and then overdried for 12 h after the reaction is completed (page 3904, Right Col., para. 5).
However, these references do not teach the step of washing the fibrous material.
Eriksen et al. teaches a process and apparatus for the preparation of a modified lignocellulosic material (Abstract). It is believed that washing the product in water would remove the remaining chemicals, which have a bad odor (Col. 11, lines 8 – 11).
It would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the claimed invention to combine the teachings of Rowell et al. in view of Zafeiropoulos et al. and Nelson and further in view of Eriksen et al. by adding a wash step and by optimizing pressure in suction to arrive a method for acetylation of lignocellulosic fibrous material, further comprising the steps of elimination of remaining acetic anhydride and acetic acid residues and washing the products with water. One would have been motivated to implement this additional steps for the sake of a more purified product. Rowell et al. teach applying suction and Zafeiropoulos et al. teach in a vacuum with pressure of 0.003 MPa, one skilled in the art would understand that the application of suction to drain the acetic anhydride will create a condition where the pressure is reduced and the recorded pressure will be based on the suction force, such as 0.003 MPa as disclosed by Zafeiropoulos et al.. Therefore, one would have been performed a routine experimentation to discover the best suction force (reduced pressure) for the optimal filtration to be performed. One of the skills in the art would have had a reasonable expectation of success by adding a wash step and by optimizing pressure in suction to arrive a method for acetylation of lignocellulosic fibrous material, further comprising the steps of elimination of remaining acetic anhydride and acetic acid residues and washing the products using water for the purpose of removing the bad odor.
Responses to Applicant’s Remarks:
Applicant’s Remarks, filed December 23, 2025, have been fully considered and are found to be not persuasive..
Regarding Rowell et al., Applicant argues that Rowell et al. do not disclose, teach, or suggest the claimed acetyl value/DS ranges for non-wood, non-jute fibers under non-catalytic, near-ambient pressure of the amended claim 1. Applicant argues that it is not possible to produce jute with a degree of substitution or acetyl value as required by amended claim 1 under the conditions disclosed in Rowell et al. Applicant argues that the amended claim 1 exclude wood and jute, but Rowell et al. cover wood and jute.
Regarding Chung et al., Applicant argues that Chung et al. achieve a DS of about 1.5 using a pyridine catalyst on kenaf and Chung et al. cannot supply the missing limitations under the non-catalytic constraint of claim 1. Applicant argues that Chung et al. optimize the acetylation time, but not the DS. Applicant argues that the DS disclosed by Chung et al. is not a teaching that is obtainable under Rowell’s non-catalytic conditions. Applicant argues that Chung et al. disclose kenaf, which is also known as java jute. Applicant further argues that Chung et al. provide no suggestion that non-catalytic acetylation at near-ambient pressure on the claim-recited fibers will achieve the claimed acetyl value and DS.
Regarding the combination of Rowell et al. and Chung et al., Applicant argues that there is no articulated rationale with reasonable expectation of success to reach the specific acetyl value and DS ranges on the claimed fibers under non-catalytic, near-ambient pressure and routine experimentation does not bridge the gap to achieving the claimed acetyl value and DS ranges.
Regarding Eriksen et al. and Nelson, Applicant argues that these references do not cure the deficiencies of Rowell et al. and Chung et al. because Eriksen et al. teach that washing with water can remove remaining chemicals/odor and Nelson teaches continuous processing and recirculation at certain parameters.
However, these arguments are not persuasive because the rejections are no longer based on Rowell et al. in view of Chung et al. The claims are now rejected over Rowell et al. in view of Zafeiropoulos et al. and Nelson, and further in view of Eriksen et al. The combination of these references addresses the limitations of the claims because Rowell et al. teach the acetylation process for lignocellulosic fibrous material using acetic anhydride under non-catalytic and near-ambient pressure conditions, Zafeiropoulos et al. explicitly teach the use of Rowell’s method for acetylating flax fiber, Nelson teaches that gaseous acetic anhydride, continuous process, and precise duration of acetylation contribute to obtaining the desired acetyl value and DS, and Eriksen et al. teach that washing step is common step for removing bad odor and chemical impurities. Therefore, the combination of Rowell et al., Zafeiropoulos et al., Nelson, and Eriksen et al. render the claims obvious.
Conclusion
No claim is found to be allowable.
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.Y.L./Examiner, Art Unit 1693
/SCARLETT Y GOON/Supervisory Patent Examiner, Art Unit 1693