DETAILED CORRESPONDENCE
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 Arguments
Applicant's arguments have been fully considered.
Applicant argues that “The Examiner has not provided any evidence or technical reasoning to establish that unmodified carbon nanotubes necessarily or inherently have a purity greater than 95% carbon.” (Remarks, Pg. 7)
Examiner does not find this persuasive because the plain meaning of the term carbon nanotube is an allotrope of carbon, a nanotube made of carbon.
A carbon nanotube is, by definition, sp2 bonded carbons arranged in a tube. Similarly diamond is by definition 2p3 bonded carbons arranged in a lattice. Diamond can be modified to contain other elements and carbon nanotubes can be modified to contain other elements. Nevertheless, the meaning of these base terms, diamond and carbon nanotube, are that they are allotropes of carbon; they are by definition pure carbon.
Applicant argues that “Zhang's carbon nanotubes have been chemically modified through a carboxylation process … The introduction of these oxygen-containing groups necessarily reduces the carbon purity of the nanotubes below 95%, as the carboxyl groups contain oxygen atoms that displace carbon in the overall composition of the material.” (Remarks Pg. 7)
Examiner does not find this persuasive for two reasons:
First, This is mere attorney argument that is presented without evidence; and runs contrary to the evidence now of record.
Zhang treats the surface of the carbon nanotubes with hot concentrated sulfuric/nitric acid1. Based on the argument, it is understood that Applicant considers the sum of the nanotube and the surface treatment to be the claimed nanotube. Thus, in order to determine if that Zhang’s surface treated (carboxylated) nanotubes are less than 95% carbon, we would need to know how much oxygen/carboxyl is added to the surface. Zhang has not disclosed this. Applicant’s allegation is without evidence.
Since Zhang does not disclose the degree of surface carboxylation, we can look to the literature or other patent documents for similar processing and outcomes. For example, US 20260117078 A1 demonstrates a process similar to Zhang which “involves exposing carbon nanotubes to reflux in concentrated sulfuric/nitric acid. The resulting carboxylated carbon nanotubes have from about 2 wt % to about 7 wt % COOH groups.” (Paragraph 21).
This is similar to Zhang’s process of treating carbon nanotubes with hot concentrated sulfuric/nitric acid. Thus, we would expect Zhang’s process to also result in carboxylated carbon nanotubes having from about 2 wt % to about 7 wt % COOH groups.
A carboxylate is about 27% carbon. A carboxylated carbon nanotubes having from about 2 wt % to about 7 wt % COOH groups would have about 95% to 99% of carbon.
The evidence is the opposite of Applicant’s allegation and supports the presumption that Zhang’s carbon nanotubes are 95% carbon.
Second, the rejection relies on Grotziner. Grotziner indicates that carbon nanotubes can be used for the same purpose and does not disclose treating the carbon nanotubes. Grotziner’s use of the term “carbon nanotube” and silence regarding surface treatment implies that their carbon nanotubes do not have additional groups attached to the surface. Based on Grotziner, a person of skill in the art would appreciate that pure carbon nanotubes could be used as the carbon additive.
Applicant argues that Grotziner’s carbon nanotubes are not pure.
Examiner does not find this persuasive because there is no evidence that Grotziner’s carbon nanotubes are not pure. The plain meaning of carbon nanotube is a nanotube made of carbon.
Applicant argues that “The Examiner has not provided evidence that the hypothetically modified composition would inherently possess the claimed resistivity ranges of claims 2 and 3, the thermal expansion coefficient of claim 4, or the viscosity and pot life of claim 18… Changing the filler content from 60 wt% to greater than 80 wt% would substantially alter the composition and its properties in ways that cannot be predicted without actual testing.”
Examiner does not find this persuasive because the evidence that the prior art composition would have the same properties is that the prior art ingredients are the same. The prior art is the combination.
Yeo teaches a similar epoxy (title) using 80% filler (Abstract, Fig 5) and demonstrates that as filler content increases so does conductivity, e.g., see Fig. 5 and 6a, copied below.
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When Zhang is modified to have greater amounts of conductive filler, then the expected result would be higher conductivity. This is expected based on Yeo’s experimental results. This is an expected result.
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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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.
Claim 1-8, 16, 18, and 20-21 and is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang (CN109206853A) and in view of Yeo (NPL 20172) as evidenced by Chen (US 20260117078 A1) and/or further in view of Grötzinger (US 20230265260 A1)
In reference to claim 1 and 16, Zhang discloses an epoxy molding compound, comprising: (“epoxy resin” [Pg 2])
a hardener; (“curing agent, and the catalyst” [Pg. 2])
a catalyst to accelerate curing of the epoxy molding compound; and (“curing agent, and the catalyst” [Pg. 2])
an inorganic based filler, … and a conductive additive, wherein an amount of the conductive additive comprises 0.1 to 5 wt % of the epoxy molding compound (“Alumina mass fraction: 30 wt% to 60 wt%; further, carboxylated carbon nanotubes are added, and the mass fraction is from 1 wt% to 3 wt%, and the mixture is heated and stirred at 60 ° C to 80 ° C to prepare a slurry for use.” [Top of Pg. 3]. Also see table in Chinese document showing example ranges).
Zhang teaches the inorganic filler is provided at up to 60wt% whereas the claim requires the inorganic filler at greater than 80 wt%.
In the same field of endeavor or reasonably pertinent to the particular problem faced by the inventor, conductive epoxy, Yeo discloses a similar epoxy (title) using an alumina filler (Abstract) and demonstrates that as filler content increases so does conductivity, e.g., see Fig. 5 and 6a, copied below.
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Yeo teaches that inorganic filler and conductive are positively related and that it is desirable to increase conductivity of epoxy for applications.
Both Yeo and Zhang use the same inorganic filler, and the same inorganic filler that Applicant claims.
Therefore, it would have been obvious to one of ordinary skill in the art with a reasonable expectation of success before the effective filing date of the claimed invention to configure Zhang’s epoxy such that the conductivity of was increased by increasing the filler and thereby arrive at the claimed invention.
Yeo explicitly teaches the idea of increasing filler content to achieve desired properties at equation 42 (page 102), which shows that thermal conductivity of the composite (lamda_c) is positive correlated with the volume fraction of the filler particles (V). A person of skill in the art would have known that adding thermally conductive filler increases thermal conductivity, but changes other properties (e.g., processability).
While it is recognized that Yeo warns that "some important physical properties of composites such as processability and mechanical strength (durability) are significantly diminished by the use of fillers with high concentration." Yeo further states that "developing heat dissipating materials with low filler loading has been a development trend in field of materials sciences." However this does not constitute teaching away. Recognizing that adding more thermally conductive filler may make processing more difficult is not a teaching away3. The context of this quoted section of Yeo is directed to a general background section on thermally conductive materials and is would not be read by a person of skill in the art as specific commentary on their materials or a specific warning.
Zhang teaches carbon nanostructures (e.g., “carboxylated carbon nanotubes are added, and the mass fraction is from 1 wt% to 3 wt%” [Top of Pg. 3]), but Zhang does not specifically teach the use of pure carbon nanostructures having a carbon purity of 95%.
Zhang treats the surface of the carbon nanotubes with hot concentrated sulfuric/nitric acid to carboxylate them4. In order to determine if that Zhang’s surface treated (carboxylated) nanotubes are more or less than 95% carbon, we would need to know how much oxygen/carboxyl is added to the surface, however, Zhang has not disclosed this.
Since Zhang does not disclose the degree of surface carboxylation, we can look to the literature or other patent documents for similar processing and outcomes. For example, Chen (US 20260117078 A1) demonstrates a process similar to Zhang which “involves exposing carbon nanotubes to reflux in concentrated sulfuric/nitric acid. The resulting carboxylated carbon nanotubes have from about 2 wt % to about 7 wt % COOH groups.” (Paragraph 21).
This is similar to Zhang’s process of treating carbon nanotubes with hot concentrated sulfuric/nitric acid. Thus, we would expect Zhang’s process to also result in carboxylated carbon nanotubes having from about 2 wt % to about 7 wt % COOH groups.
A carboxylate (COOH) is about 27% carbon. Carboxylated carbon nanotubes having from about 2 wt % to about 7 wt % COOH groups would have about 95% to 99% of carbon.
The evidence thus supports the presumption that Zhang’s carbon nanotubes are 95% carbon.
Alternatively, the rejection further relies on Grotziner:
In the same field of endeavor or reasonably pertinent to the particular problem faced by the inventor, conductive compounds (see title), Grötzinger teaches a similar invention (see claims) and explains that “carbon nanotubes (CNTs) are known” (P0005). Grötzinger does not indicate the nanotubes are modified, thus they are presumed to be pure.
Grotziner indicates that carbon nanotubes can be used for the same purpose and does not disclose treating the carbon nanotubes. Grotziner’s use of the term “carbon nanotube” and silence regarding surface treatment implies that their carbon nanotubes do not have additional groups attached to the surface. Based on Grotziner, a person of skill in the art would appreciate that pure carbon nanotubes could be used as the carbon additive.
Therefore, it would have been obvious to one of ordinary skill in the art with a reasonable expectation of success before the effective filing date of the claimed invention to configure the epoxy to use pure carbon nanotubes as the carbon as an art recognized alternative suitable for the same use.
In reference to claim 2-4 and 18 the cited prior art discloses the invention as in claim 1.
The prior art teaches the same compound and must have the same properties.
In reference to claim 5, 7 the cited prior art discloses the invention as in claim 1.
Zhang teaches the claim (e.g., “carboxylated carbon nanotubes are added, and the mass fraction is from 1 wt% to 3 wt%” [Top of Pg. 3]; and “Carbon-based fillers have good thermal conductivity, and carbon-based fillers include carbon nanotubes, graphene, expanded graphite, and the like” [Bottom of Pg. 1])
In reference to claim 6 the cited prior art discloses the invention as in claim 1.
Zhang teaches carbon nanostructures (e.g., “carboxylated carbon nanotubes are added, and the mass fraction is from 1 wt% to 3 wt%” [Top of Pg. 3]), but Zhang does not specifically require the nanostructure is 0.1-0.5% of the epoxy.
In the same field of endeavor or reasonably pertinent to the particular problem faced by the inventor, conductive compounds (see title), Grötzinger teaches a similar invention (see claims) and explains that “carbon nanotubes (CNTs) are known” (P0005) and that “a very small amount of carbon nanotubes by weight enables good electrical conductivity, but also brings about a distinct increase in viscosity and levelling properties and a certain darkening of the coating” (P0033)
Grötzinger thus teaches that “a dispersion comprising 10% by weight of carbon nanotubes is used, preferably in an amount in the range from 0.01% to 1% by weight, especially 0.01% 0.5% by weight, based on the overall epoxy resin” (P0037).
Therefore, it would have been obvious to one of ordinary skill in the art with a reasonable expectation of success before the effective filing date of the claimed invention to configure the epoxy to reduce the amount of carbon additive to 0.01% 0.5% as suggested by Grötzinger because “In this range, the desired electrical conductivity and non-excessive darkening are achieved” (P0038 of Grötzinger).
In reference to claim 8 the cited prior art discloses the invention as in claim 1.
Zhang teaches the “Carbon-based fillers have good thermal conductivity, and carbon-based fillers include carbon nanotubes, graphene, expanded graphite, and the like” (Bottom of Pg. 1), but does not specifically require carbon black.
In the same field of endeavor or reasonably pertinent to the particular problem faced by the inventor, conductive compounds (see title), Grötzinger teaches a similar invention (see claims) and teaches a similar epoxy that can comprise carbon black (P0087 and P0098) and that “the addition of conductive carbon black or graphite, which does achieve a reliable conductivity” (P0005)..
Therefore, it would have been obvious to one of ordinary skill in the art with a reasonable expectation of success before the effective filing date of the claimed invention to configure the epoxy to use carbon black as the carbon as an art recognized alternative suitable for the same use.
In reference to claim 17 the cited prior art discloses the invention as in claim 1.
The plain meaning of the term carbon nanotube is an allotrope of carbon, a nanotube made of carbon.
A carbon nanotube is, by definition, sp2 bonded carbons arranged in a tube. Similarly diamond is by definition 2p3 bonded carbons arranged in a lattice. Diamond can be modified to contain other elements and carbon nanotubes can be modified to contain other elements. Nevertheless, the meaning of these base terms, diamond and carbon nanotube, are that they are allotropes of carbon; they are by definition pure carbon.
The prior art refers to carbon materials and does not present a percentage of additives in the carbon greater than 5%, thus the carbon is 95% pure.
Furthermore, pure carbon nanotubes are well known for the intended use of improving heat transfer through a matrix – this is because carbon atoms in a nanotube form tight, stiff covalent bonds. These strong bonds create a high speed of sound in the material, which helps transfer thermal energy rapidly. This would be obvious to a person of skill in the art.
In reference to claim 20 the cited prior art discloses the invention as in claim 1.
Zhang adds a silane couping agent (“Alumina microspheres of different sizes (5 μm, 20 μm, 70 μm) were surface-modified with a silane coupling agent having an epoxy group”)
In reference to claim 21 the cited prior art discloses the invention as in claim 1.
Zhang and Yeo use epoxy resins as claimed.
Claim 19 and is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhang (CN109206853A) and in view of Yeo (NPL 20175) as evidenced by Chen (US 20260117078 A1) and/or further in view of Grötzinger (US 20230265260 A1) and further in view of HallGoulle (US 20010000259 A1).
In reference to claim 19 the cited prior art discloses the invention as in claim 1.
The prior art generally references the use of catalyst for epoxy curing, but does not describe an imidazole catalyst.
The relevant prior art of HallGoulle teaches that “The use of unsubstituted or substituted imidazole as a curing catalyst in the curing of epoxy resins is known. For example, H. Lee and K. Neville in "Handbook of Epoxy Resins", pages 10-17 (1967), report the property of epoxy resins cured with 2-ethyl-4-methylimidazole.” (Paragraph 2).
It would have been obvious to one of ordinary skill in the art with a reasonable expectation of success before the effective filing date of the claimed invention to configure Zhang’s epoxy such that the catalyst was an imidazole because imidazole is an art recognized substitute suitable for the same intended use in order to provide suitable catalyzation.
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 regarding this communication or earlier communications from the examiner should be directed to NICHOLAS KRASNOW whose telephone number is (571)270-1154. The examiner can normally be reached M-R: 8am-5pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Xiao Zhao can be reached at 571-270-5343. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Examiner has utilized USPTO approved search resources, such as EIC or external tools, beyond routine search tools and/or leveraged experts in the field. Examiner has cited and explained the relevance of prior art not used in rejections but pertinent to the claims or disclosure. Examiner has provided detailed search documentation through detailed Search Notes, such as annotated search results that identify which data sets were reviewed. When citing the prior art examiner has used annotations clearly in prior art rejections such as, using item-to-item matching to the prior art, pairing exact claim language to particular language used in the prior art, and/or clearly explaining examiner’s interpretation as to how a citation maps to claim language especially when there is not a one-to-one matching of terms.
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/NICHOLAS KRASNOW/Examiner, Art Unit 1744
1 Carbon nanotubes are very hydrophobic. They are surface treated with strong oxidizing acids that react at defects on the surface to form COOH groups to adjust their surface properties.
2 https://www.sciencedirect.com/science/article/pii/S0266353816313252
3 By way of analogy: when making chocolate chip cookies, the recognition that adding more chocolate chips will make the batter difficult to mix is not a teaching away from making cookies with extra chocolate.
4 Carbon nanotubes are very hydrophobic. They are surface treated with strong oxidizing acids that react at defects on the surface to form COOH groups to adjust their surface properties.
5 https://www.sciencedirect.com/science/article/pii/S0266353816313252
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