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 . If status of the application as subject to 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 a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Continued Examination Under 37 CFR 1.114
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 6/5/2026 has been entered.
Status of Claims
Claims 1-16 are pending in the application. Claims 13-14 are withdrawn. Claims 1-12 & 15-16 are presently examined. Claims 1-12 & 15-16 were rejected in the 3/27/2026 office action.
Response to Amendment / Arguments
The 5/14/2026 amendment, in response to the 3/27/2026 office action, has been entered. Applicant’s claim amendments overcame the 35 U.S.C. 103 rejections; nevertheless, the claims remain rejected under 35 U.S.C. 103 due to additional prior art.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
Determining the scope and contents of the prior art.
Ascertaining the differences between the prior art and the claims at issue.
Resolving the level of ordinary skill in the pertinent art.
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 claims are in bold font, the prior art is in parentheses.
Claims 1 & 8 are rejected under 35 U.S.C. 103 as being unpatentable over US20080280115A1 (Liang) in view of US20210293742A1 (Tsuji).
With regard to claim 1, Liang teaches the following claim limitations:
A carbon nanotube dispersion (paragraphs 8-9: suspension with single wall nanotubes (SWNTs) and multiwall nanotubes (MWNTs)) comprising
carbon nanotubes (paragraph 8: SWNTs and MWNTs),
a dispersing agent (paragraph 9: the suspension also comprises a surfactant, which is a dispersing agent according to the present specification [0042]), and
a solvent (paragraph 9: the suspension also comprises acetone, which is a solvent according to the present specification [0053])…
wherein a mass ratio between the first carbon nanotubes and the second carbon nanotubes is 1:10 to 1:100 (paragraph 8: SWNT:MWNT weight ratio is 1:20 to 1:1), the first carbon nanotubes are single-walled carbon nanotubes (abstract; paragraph 8: SWNTs), and the second carbon nanotubes are multi-walled carbon nanotubes (paragraph 8: MWNTs)
Liang’s 1:20 to 1:1 weight ratio (equivalent to mass ratio) overlaps the claimed 1:10 to 1:100 mass ratio. MPEP 2144.05 (II)(A) provides the law for this issue:
“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)”
Given that Liang’s range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the claimed range is an obvious variant of Liang’s range.
Liang fails to teach the following claim 1 limitations, which are taught by Tsuji:
wherein the carbon nanotubes include first carbon nanotubes having an average outer diameter of 0.5 nm or more and less than 5 nm (paragraph 152: 1.1 to 1.7 nm single-walled carbon nanotube outer diameter) and second carbon nanotubes having an average outer diameter of 5 nm or more and 20 nm or less (paragraph 152: 5 to 15 nm multi-walled carbon nanotube outer diameter)
Tsuji is directed to “promoting electron transfer between nanocarbon and other substances” (abstract). It would have been obvious, to one of ordinary skill in the art, for Liang’s SWNT to have 1.1 to 1.7 nm outer diameter and for Liang’s MWNT to have 5 to 20 nm outer diameter, as taught by Tsuji, for promoting electron transfer between the carbon nanotubes and other substances.
The claimed diameters are specified as average diameters. Tsuji doesn’t refer to average diameters, but rather states the diameter range. Tsuji’s average diameter must be within the stated ranges, which are within the claimed ranges.
With regard to claim 8, modified Liang teaches the limitations of claim 1 as described above. Claim 8 recites:
a phase angle is 50 or more and less than 500
Modified Liang fails to teach a phase angle. Nevertheless, modified Liang teaches a suspension, which is equivalent to the carbon nanotube dispersion of claim 1; therefore, the electrode composition of modified Liang would have the phase angle of claim 8. MPEP 2112(I) provides guidance for this issue:
“‘[T]he discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition patentably new to the discoverer.’ Atlas Powder Co. v. IRECO Inc., 190 F.3d 1342, 1347, 51 USPQ2d 1943, 1947 (Fed. Cir. 1999). Thus the claiming of a new use, new function or unknown property which is inherently present in the prior art does not necessarily make the claim patentable. In re Best, 562 F.2d 1252, 1254, 195 USPQ 430, 433 (CCPA 1977).”
The patent office does not have the ability to test, or to obtain data for, every possible property. Measurement of a property does not make an old substance patentable.
Claims 2 & 7 are rejected under 35 U.S.C. 103 as being unpatentable over US20080280115A1 (Liang) in view of US20210293742A1 (Tsuji), as applied to claim 1, and further in view of US20190044150A1 (Kim).
With regard to claim 2, modified Liang teaches the limitations of claim 1 as described above. Liang, however, fails to teach the following claim 2 limitation, which is taught by Kim:
a total BET specific surface area of the first carbon nanotubes and the second carbon nanotubes is 240 m2/g to 750 m2/g (paragraph 47: 230 to 300 m2/g)
Kim’s 230 to 300 m2/g overlaps the claimed 240 m2/g to 750 m2/g. MPEP 2144.05 (II)(A), provides the law for this issue:
“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)”.
Given that Kim’s range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the BET range in claim 2 is an obvious variant of Kim’s range.
Kim teaches the 230 to 300 m2/g range for excellent dispersibility (paragraph 47). Kim’s carbon nanotubes can be single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (paragraphs 37-38). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Liang’s carbon nanotubes to have 230 to 300 m2/g BET, as taught by Kim, for excellent dispersibility.
With regard to claim 7, modified Liang teaches the limitations of claim 1 as described above. Liang, however, fails to teach the following claim 7 limitation, which is taught by Kim:
a complex elastic modulus is 5 Pa or more and less than 650 Pa (paragraphs 12-13: 20 to 500 Pa complex modulus)
Kim is directed to a conductive material dispersed liquid with a complex modulus controlled for excellent dispersibility and improved battery output characteristics. It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for modified Liang’s suspension to have 20 to 500 Pa complex modulus, as taught by Kim, for excellent dispersibility and improved battery output characteristics.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over US20080280115A1 (Liang) in view of US20210293742A1 (Tsuji), as applied to claim 1, and further in view of US20190177166A1 (Oh). Modified Xu fails to teach the following claim 4 limitation, which is taught by Oh:
in a Raman spectrum of the first carbon nanotubes, when a maximum peak intensity in a range of 1,560 cm-1 to 1,600 cm-1 is G, and a maximum peak intensity in a range of 1,310 cm-1 to 1,350 cm-1 is D, the G/D ratio is 10 to 100 (paragraph 70, table 2, Example 1: IG/ID=10.41; paragraphs 13-14 define IG/ID)
Oh is directed to an efficient method for producing carbon nanotubes (paragraph 12). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Liang’s SWNTs to have IG/ID=10.41, as taught by Oh, resulting from an efficient method for producing carbon nanotubes.
Claims 5-6 are rejected under 35 U.S.C. 103 as being unpatentable over US20080280115A1 (Liang) in view of US20210293742A1 (Tsuji), as applied to claim 1, and further in view of US20210226222A1 (Morita).
With regard to claim 5, modified Liang teaches the limitations of claim 1 as described above. Modified Liang, however, fails to teach the following claim 5 limitation, which is taught by Morita:
a BET specific surface area of the first carbon nanotubes is 600 m2/g to 1,200 m2/g (paragraph 69: BET = 400–800 m2/g)
Morita is directed to a carbon nanotube dispersion with high dispersibility (paragraphs 5 & 15). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Liang’s SWNTs to have 400–800 m2/g BET, as taught by Morita, for high dispersibility.
Morita’s 400–800 m2/g range overlaps the claimed 600–1200 m2/g range. MPEP 2144.05 (II)(A) provides the law for this issue:
“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)”.
Given that Morita’s range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the range in claim 5 is an obvious variant of Morita’s range.
With regard to claim 6, modified Liang teaches the limitations of claim 1 as described above. Modified Liang, however, fails to teach the following claim 6 limitation, which is taught by Morita:
a volume resistivity of the first carbon nanotubes is 1.0x10-3 Ω⋅cm to 3.0x10-2 Ω⋅cm (paragraph 42: volume resistivity = 1.0x10-3 Ω⋅cm to 2.5x10-2 Ω⋅cm)
Morita is directed to a carbon nanotube dispersion with high dispersibility (paragraphs 5 & 15). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Liang’s SWNTs to have 1.0x10-3 Ω⋅cm to 2.5x10-2 Ω⋅cm, as taught by Morita, for high dispersibility.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over US20080280115A1 (Liang) in view of US20210293742A1 (Tsuji), as applied to claim 1, and further in view of US20190051887A1 (Yoo). Modified Xu fails to teach the following claim 9 limitations, which are taught by Yoo:
the carbon nanotube dispersion includes 0.3 parts by mass or more and 5.0 parts by mass or less of the carbon nanotubes in 100 parts by mass of the carbon nanotube dispersion; and the carbon nanotube dispersion has a viscosity of 10 mPa·s or more and less than 2,000 mPa·s (paragraphs 29-30: 1% to 5% by weight; 1 Pa⋅s to 120 Pa⋅s = 1000 mPa⋅s to 120,000 mPa⋅s); and
Yoo is directed to a carbon nanotube dispersion with carbon nanotubes uniformly dispersed (paragraphs 7-8). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Liang’s suspension to have 1% to 5% carbon nanotubes by weight and 1000–120,000 mPa*s viscosity, as taught by Yoo, for uniform dispersion.
Yoo teaches 1% to 5% carbon nanotubes by weight (paragraph 30) and 1000–120,000 mPa*s viscosity (paragraph 29) in separate embodiments. Yoo, however, combines these concepts in the examples (paragraphs 80-98). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, to combine Yoo’s 1% to 5% carbon nanotubes by weight with 1000–120,000 mPa*s viscosity, based on Yoo’s examples.
Yoo’s 1000-120,000 mPa⋅s range overlaps the claimed 10-2000 mPa⋅s range. MPEP 2144.05 (II)(A) provides the law for this issue:
“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)”.
Given that Yoo’s range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the range in claim 9 is an obvious variant of Yoo’s range.
Claim 9 also recites:
the viscosity measured at 25°C using a B type viscometer rotor at a rotation speed of 60 rpm
Yoo doesn’t teach this method of measuring viscosity. Claim 9, however, is an apparatus claim for a carbon nanotube dispersion. Claim 9 is not a method of measurement claim. This recitation of how the viscosity is measured does not limit the scope of the claim for patent examination purposes. The carbon nanotube dispersion and its properties are examined — not the method of measuring those properties.
Claims 10-12 & 15-16 are rejected under 35 U.S.C. 103 as being unpatentable over US20080280115A1 (Liang) in view of US20210293742A1 (Tsuji), as applied to claim 1, and further in view of US20130004657A1 (Xu).
With regard to claim 10, modified Liang teaches the limitations of claim 1 as described above. Modified Liang fails to teach the following claim 10 limitations, which are taught by Xu:
a cumulative particle size D50 of the carbon nanotube dispersion measured by a dynamic light scattering method is 400 nm to 4,000 nm (paragraph 73: 1-10 micrometers = 1000-10,000 nm); and
Xu is directed to carbon nanotube compositions for better electrical contact. It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Liang’s suspension to have 1000-10,000 nm size, as taught by Xu, for better electrical contact.
Xu’s 1000-10,000 nm range overlaps the claimed 400-4000 nm range. MPEP 2144.05 (II)(A) provides the law for this issue:
“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)”
Given that Xu’s range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the range in claim 10 is an obvious variant of Xu’s range.
Xu doesn’t teach the claimed method of measuring cumulative particle size D50. Claim 10, however, is an apparatus claim for a carbon nanotube dispersion. Claim 10 is not a method of measurement claim. This recitation of how cumulative particle size D50 is measured does not limit the scope of the claim for patent examination purposes. The carbon nanotube dispersion and its properties are examined — not the method of measuring those properties.
With regard to claims 11-12 & 15-16, modified Liang teaches the limitations of claim 1 as described above. Modified Liang fails to teach the following limitations of claims 11-12 & 15-16, which are taught by Xu:
Claim 11
A carbon nanotube resin composition comprising the carbon nanotube dispersion according to claim 1 and a binder (paragraphs 6, 20, & 22)
Claim 12
A mixture slurry comprising the carbon nanotube resin composition according to claim 11 and an active material (paragraphs 35 & 38; figure 1A)
Claim 15
An electrode film obtained by forming the mixture slurry according to claim 12 into a film (paragraph 39; figure 1B)
Claim 16
A nonaqueous electrolyte secondary battery comprising a positive electrode, a negative electrode, and an electrolyte, wherein at least one of the positive electrode and the negative electrode includes the electrode film according to claim 15 (paragraphs 20-22)
Xu’s carbon nanotube compositions are intended to be used for an electrode for a Li ion battery, in order to improve electrical contact such that battery performance is enhanced. It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Liang’s suspension to be combined with the components of claims 11-12 & 15-16, in order to improve electrical contact such that battery performance is enhanced.
Allowable Subject Matter
Claim 3 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. The following is a statement of reasons for allowable subject matter:
JP2018097961A (Araki), US20190044150A1 (Kim), and “Effect of aspect ratio on thermal conductivity of high density polyethylene/multi-walled carbon nanotubes nanocomposites” (Evgin) are the closest prior art for claim 3. Claim 3 states:
wherein an aspect ratio of the first carbon nanotubes is 2,000 to 10,000, and
wherein an aspect ratio of the second carbon nanotubes is 50 to 200
In the following table are dimensions of Araki’s first carbon nanotube (1st CNT) and second carbon nanotube (2nd CNT), and the resulting aspect ratio (AR) (Araki page 12, lines 39-41). 2nd CNT is listed in two separate rows because Araki teaches a range for 2nd CNT dimensions instead of a single value.
diameter
length
AR
1st CNT
1.4 nm
5000 nm
3571
2nd CNT
10 nm
11,000 nm
1100
2nd CNT
15 nm
7000 nm
466
Note: Araki lists the lengths in micrometer (μm) units, but these lengths are listed in the table in nanometer (nm) units for easier calculation of the aspect ratio (AR).
Here are problems with Araki; i.e. reasons claim 3 is not obvious over Araki alone:
Araki teaches AR=466-1100 for the 2nd CNT, which is outside of, and not very close to, the AR=50-200 range for the claimed MWCNT.
Araki teaches that the carbon nanotubes can include SWCNT & MWCNT (page 7, lines 15-17); however, Araki fails to teach which of the 1st CNT and 2nd CNT is SWCNT and which is MWCNT.
Regarding Araki problem #2, Kim provides additional guidance. Kim teaches CNT AR=10-20,000 (paragraph 41). Arguably, the claimed AR=50-200 range for MWCNT is obvious over Kim’s 10-20,000 range; however, there are problems with that reasoning:
Although Kim teaches that CNTs can be SWCNT or MWCNT, Kim doesn’t teach a mixture of SWCNT or MWCNT. The optimal AR for MWCNT would be different in a mixture with SWCNT than for MWCNT alone (see present specification page 20, lines 1-9).
Kim doesn’t teach that AR=10-20,000 is for the MWCNT.
Kim’s AR=10-20,000 range overlaps, but not closely, with the claimed AR=50-200. The claimed range covers only 0.8% of Kim’s range.
Evgin provides additional guidance. Evgin teaches MWCNT AR in ranges of 200–400 and 500–3000; thus, Evgin teaches an AR range that borders the claimed 50-200 range. Evgin, however, teaches that “MWCNTs with higher aspect ratio have higher thermal conductivities than the ones with lower aspect ratio” (abstract). Evgin thus teaches away from the lower AR range that borders the claimed AR range.
Conclusion
Prior art not relied upon, but made of record and considered pertinent to applicant's disclosure:
US20130337326A1 teaches 2 parts by weight single-walled CNTs and 5 parts by weight multi-walled CNTs [0147].
US20100159222A1 teaches mixing single-walled carbon nanotubes and multi-walled carbon nanotubes “in a suitable ratio” [0083].
US10480771B1 teaches a carbon composite material with SWCNTs and MWCNTs (claim 7).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ROBERT WEST whose telephone number is 703-756-1363 and email address is Robert.West@uspto.gov. The examiner can normally be reached Monday-Friday 10 am - 7 pm ET.
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, Allison Bourke can be reached at 303-297-4684.
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.
/R.G.W./Examiner, Art Unit 1721
Prosecution Insights