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 .
This office action is in response to applicant’s amendments filed on December 15, 2025. Claims 1-8 are pending. Claim 9 has been cancelled. Claims 1,4 and 6-8 have been amended.
All prior objections and rejections are withdrawn in view of applicant’s amendments to the claims and drawings.
Drawings
The drawings were received on December 15, 2025 These corrected drawings are accepted by the examiner.
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.
Claims 1-5,7 and 8 are rejected under 35 U.S.C. 103 as being unpatentable over Shao (CN 101016659A) in view of Kosan (US 20030159620).
Shao teaches preparing dope dyed lyocell by combining carbon nanotubes (black pigment) with NMMO (N-methylmorpholine-N -oxide) water and cellulose pulp, removing water by vacuum distillation to a water content of 12-14% and a carbon nanotube content of 0.1-10% wherein the prepared black spinning dope is extruded through a spinneret to form dope dyed lyocell (page 4, paragraphs 3-4). Example 1, paragraphs 4 and 5 produce a black spinning stock with 13.3% water and 1% carbon nanotubes in the extruded fiber. Example 2, paragraphs 4 and 5 produce a black spinning stock with 12% water and 0.5% carbon nanotubes in the extruded fiber. Example 3, paragraphs 4 and 5 produce a black spinning stock with 13.8% water and 5% carbon nanotubes in the extruded fiber.
Shao does not teach applying a vacuum to the pigment and NMMO solvent slurry at 90-105°C prior to adding the cellulose dope. Shao does not specify the elongation at break or colorfastness values.
Kosan teaches a lyocell process comprising vacuum distillation of cellulose pulp in the presence of NMMO solution and additives such as colorants and pigments is effectively performed at 60-100°C, with 90°C exemplified to dissolve the cellulose and distill off the water to a desired water content (paragraph 0018, 0033, 0037).
It would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the methods of Shao by vacuum dehydrating the slurry of NMMO, water and pigment at 90-100°C as Kosan teaches the same combination of components of cellulose, NMMO, water and carbon nanotube (colorant/pigment) is vacuum distilled at this temperature to remove water. It would have been obvious to use a known effective vacuum distillation temperature in the methods of Shao because Kosan teaches this temperature range is efficient in producing the same desired result of water removal as Shao. Regarding the order of steps, particularly the separation of claimed steps (b) and (c), nothing unobvious is seen in combining the steps or performing them sequentially as the same product of the dehydrated composition is achieved. Particularly the carbon nanotube colorant/pigment is effectively dehydrated to a desired water content at overlapping temperature ranges. Vacuum distilling the carbon nanotube prior to adding the cellulose dope or adding only 0.5-5% of the cellulose dope and vacuum distilling in the presence of the cellulose dope to the claimed water content would be expected to produce similar results as the same combination of ingredients is performed followed by the same dehydration to the same water content and carbon nanotube pigment range to prepare a black spinning dope for extruding into lyocell fibers.
In general, the transposition of process steps or the splitting of one step into two, where the processes are substantially identical or equivalent in terms of function, manner and result, was held to not patentably distinguish the processes, see Ex parte Rubin, 128 USPQ 159 (PO BdPatApp 1959).
Regarding the elongation at break and the colorfastness properties, it is expected that similar lyocell fibers prepared with similar carbon nanotube black pigments, cellulose pulp, NMMO and water at similar concentrations will have similar elongation and color fastness properties as the final product has the same lyocell, water, NMMO and carbon nanotube pigment in the same amounts as applicant’s claims.
Claims 6-8 are rejected under 35 U.S.C. 103 as being unpatentable over Shao (CN 101016659A) in view of Kosan (US 20030159620) and further in view of Choi (KR 20180085857A).
Shao and Kosan are relied upon as set forth above.
Shao and Kosan do not specify the shear mixer, the elongation at break or colorfastness values.
Choi teaches when producing lyocell fibers a composition comprising cellulose fibers, NMMO and water are combined in a twin screw extruder and subjected to high shear mixing to produce a swollen dissolved cellulose dope for spinning into a lyocell fiber (abstract, paragraph 0015,0018).
It would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the methods of Shao by mixing the cellulose, NMMO, water and pigment in a shear mixer because Choi teaches twin screw extruders use high shear mixing to dissolve and swell the cellulose in water and NMMO. The shear would further evenly distribute the carbon particles to evenly color the fiber by distributing the carbon nanotubes.
Regarding the elongation at break and the colorfastness properties, it is expected that similar lyocell fibers prepared with similar carbon nanotube black pigments, cellulose pulp, NMMO and water at similar concentrations will have similar elongation and color fastness properties as the final product has the same lyocell, water, NMMO and carbon nanotube pigment in the same amounts as applicant’s claims.
Response to Arguments
Applicant’s arguments with respect to Shao and Choi as they apply to the rejections above have been considered but are not persuasive in view of the new rejections. The examiner argues that Shao teaches adding a carbon nanotubes into a lyocell dope wherein the carbon nanotubes are black and would color the lyocell black, producing a black dope dyes lyocell fiber. The coloration is an inherent property of the dope dyed lyocell fiber of Shao even if the method of Shao is not explicitly described as a dyeing process. The same chemicals are combined to produce a fiber which contains a black pigment in the dope. And the fiber is extruded after the dope is pigmented. Both processes are directed towards effectively incorporating carbon nanotube pigments into lyocell dope and extruding the dope into fibers. Coloration is just an unstated property the carbon nanotube provides to the lyocell dope. Applicant’s own specification teaches carbon pigments such as carbon black and emphasizes the need for stable dispersions wherein the particles do not agglomerate or clump (paragraph 0004). Shao teaches the thermal stability of the carbon nanotubes and their uniform dispersion (page 1, last line, page 2, background technique). The uniform dispersion of the carbon nanotubes would provide color uniformity as they are equally spread out and dispersed in the lyocell dope and resultant fiber and they are the coloring agent for the lyocell dope and fiber. Uniform distribution of a coloring particle in a fiber produces a uniform color.
Regarding the order of steps of applicant’s claim 1a-1c, applicant has not demonstrated the criticality of the sequential steps 1a,1b and 1c in the form of experimental data in a manner commensurate in scope with the claims and comparative to Shao. Applicant simply argues the claimed process provides improvement. It is the examiner’s position that Shao in view of new reference Kosan combines steps 1a,1b and 1c into a single step, but conducts the same vacuum dehydration, mixing and extrusion to produce the same colored fiber with color uniformity and stability due to uniform distribution of the carbon nanotube particles in the dope and fiber. In general, the transposition of process steps or the splitting of one step into two, where the processes are substantially identical or equivalent in terms of function, manner and result, was held to not patentably distinguish the processes, see Ex parte Rubin, 128 USPQ 159 (PO BdPatApp 1959). Shao in vie of Kosan would produce a masterbatch of pigment, NMMO and lyocell with the same water content and the shade can be determined by the amount of the addition of the carbon nanotubes to the lyocell dope. Since carbon nanotubes need to be metered into the lyocell dope in applicant’s invention and in Shao, and in both cases the water content must be adjusted, this can be done simultaneously or sequentially but the fiber produced has a color based on the amount of carbon nanotube added to the dope resulting in the desired shading. Applicant argues Choi does not overcome the deficiencies of Shao but does not further argue the combination of references, so the examiner’s arguments based on Shao are relied upon for Shao and Choi. .
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to AMINA S KHAN whose telephone number is (571)272-5573. The examiner can normally be reached Monday-Friday, 9am-5:30pm EST.
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/AMINA S KHAN/Primary Examiner, Art Unit 1761
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