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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 07/13/2026 has been entered.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim 10-27 is rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Particularly, Claim 19 requires “a method of purifying carbon black obtained exclusively from a pyrolysis of tires”, requiring that the carbon black comprise no carbon black that is not derived from pyrolysis of tires. However, the instant published specification at [0004] discloses "[t]he present invention relates to a purification process of the carbon black obtained from the pyrolysis of used tyres by means of solvent extraction characterized by low or zero toxicity and environmental impact, preferably—but not exclusively—derived from raw materials from renewable and non-fossil sources". The specification therefore implies that the invention is drawn to a method of purifying a carbon black not exclusively derived from pyrolysis of tires. There exist no embodiments in the instant application that disclose the exclusive use of carbon black derived from pyrolysis of tires. Therefore, there appears to be a lack of support for the limitation in the claim as amended.
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:
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.
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.
Claim(s) 10, 12-14, 18-19, 21-22, 24-25 is/are rejected under 35 U.S.C. 103 as being unpatentable over Pantea et. al. (Heat-treatment of carbon blacks obtained by pyrolysis of used tires. Effect on the surface chemistry, porosity and electrical conductivity, Journal of Analytical and Applied Pyrolysis, 2003), hereinafter ‘Pantea’, in view of Bernardo et. al., “Characterization of chars produced in the co-pyrolysis of different wastes: Decontamination study,” Journal of Hazardous Materials 207–208 (2012) 28–35, hereinafter ‘Bernardo’.
Regarding Claim 10 and 19, Pantea discloses a method of purifying carbon black obtained from a pyrolysis of used tires, the method comprising:
performing a heat treatment of the carbon black obtained from the pyrolysis of used tires in an inert atmosphere at a temperature between 500°C and 750°C (2.1. Tire pyrolysis and post-pyrolysis heat treatment of the pyrolytic carbon blacks: carbon black generated exclusively from pyrolysis of tires was heat-treated at 670 °C under flowing nitrogen, which is considered an inert atmosphere).
Further regarding Claim 10 and 19, Pantea does not disclose subsequently extracting the heat-treated carbon black with an extraction solvent.
Bernardo discloses a study regarding the production of chars including carbon black from a mixture comprising used tires (Introduction). A person of ordinary skill in the art would have recognized Bernardo as analogous to Pantea, as both references are drawn to the same field of endeavor as the claimed invention, the pyrolysis of tires to produce char - a reference is analogous art to the claimed invention if the reference is from the same field of endeavor as the claimed invention, In re Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
Further, Bernardo discloses that chars produced by pyrolysis of used tires may contain a wide range of toxic substances including heavy metals and organic compounds distributed by a porous structure. Therefore, they have a toxicity potential that must be assessed in order to define their safe reutilization or disposal (Introduction). To solve this problem, Bernardo discloses subjecting the produced chars to a soxhlet extraction according to an adaptation of the EPA 3540C method, wherein several organic solvents with different polarities were used (hexane, dichloromethane, a mixture of 1:1 (v/v) of hexane:acetone and ethanol, a sequential extraction of hexane, mixture of 1:1 (v/v) hexane:acetone and ethanol). Extraction was performed during 16 h at a rate of 4 cycles/h (2.2. Chars extraction: solvents selection). Bernardo discloses high extract yield of organic components within the chars (3.1. Extract yield for different extraction solvents).
Accordingly, one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to perform solvent extraction as disclosed by Bernardo to the heat-treated carbon black produced in Pantea. Given the high degree of toxicity of chars resulting from tire pyrolysis, one of ordinary skill in the art would have found it obvious to subject chars resulting from such pyrolysis to different methods of purification, including both heat treatment and solvent treatment, to minimize toxicity of the resulting chars for reuse.
Regarding Claim 12 and 24, Pantea as modified above teaches the extraction solvent is selected from the group consisting of methyltetrahydrofuran (Me-THF), tetrahydrofuran (THF), ethyl acetate (AcOEt), dimethylcarbonate (DMC), methyl acetate (AcOMe), dichloromethane (CH2Cl2), ethyl formate (HCO2Et), 3:1 vol/vol azeotropic compound of ethyl acetate, and ethanol (AcOEt/EtOH) (Bernardo discloses the use of several organic solvents with different polarities including hexane, dichloromethane, a mixture of 1:1 (v/v) of hexane:acetone and ethanol. One of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to utilize any of these solvents when applying the solvent treatment of Bernardo to the process of Pantea).
Regarding Claim 13, Pantea as modified above discloses the heat treatment in an inert atmosphere at a temperature between 500 °C and 750 °C is performed before the extracting carbon black with the extraction solvent (as discussed above, Pantea in view of Bernardo suggests subjecting the heat-treated carbon black of Pantea to solvent extraction, and therefore suggests a process in which heat treatment is performed before the extraction step).
Regarding Claims 14 and 25, Pantea as modified above teaches selective extraction of zinc from the carbon black (3.5.1. Elemental surface composition: it is shown that the carbon black samples contain zinc – further, Bernardo utilizes the same extraction solvent as that claimed, as shown above. Given this, when the carbon black of Pantea is subjected to solvent extraction as suggested by Bernardo, the zinc present in the carbon black must necessarily be selectively extracted – products having been made by the same or nearly the same process, or having the same or nearly the same composition, cannot have mutually exclusive properties. See MPEP 2112.01(I)).
Regarding Claim 18 and 21, Pantea as modified above teaches said step of heat treatment in an inert atmosphere takes place under a flow of nitrogen gas, as discussed above – this provides “a current” of an inert gas as claimed.
Regarding Claim 22, Pantea as modified above teaches discloses a step of extracting carbon black with an extraction solvent (as discussed above, Pantea in view of Bernardo suggests subjecting the heat-treated carbon black of Pantea to solvent extraction, and therefore suggests a process in which heat treatment is performed before the extraction step).
Claim(s) 11 and 23 is/are rejected under 35 U.S.C. 103 as being unpatentable over Pantea et. al. (Heat-treatment of carbon blacks obtained by pyrolysis of used tires. Effect on the surface chemistry, porosity and electrical conductivity, Journal of Analytical and Applied Pyrolysis, 2003), hereinafter ‘Pantea’, in view of Bernardo et. al., “Characterization of chars produced in the co-pyrolysis of different wastes: Decontamination study,” Journal of Hazardous Materials 207–208 (2012) 28–35, hereinafter ‘Bernardo’, as evidenced by Ceron-Carrasco et.al. “Solvent polarity scales: determination of new ET(30) values for 84 organic solvents” (2014) V. 27, Issue 6, pp. 512-518 with supplementary data (hereinafter referred to as Ceron- Carrasco).
Regarding Claim 11 and 23, Bernardo discloses the extraction solvent has a polarity between 36.5≤ ET(30)≤41.6 kcal/mol on the Reichardt scale (see evidentiary reference Ceron-Carrasco, which summarizes the ET(30) values for many organic solvents, including dichloromethane, which has an ET(30) value of 40.7 [entry 58 in the supplementary data]).
Claim(s) 15 and 26 is/are rejected under 35 U.S.C. 103 as being unpatentable over Pantea et. al. (Heat-treatment of carbon blacks obtained by pyrolysis of used tires. Effect on the surface chemistry, porosity and electrical conductivity, Journal of Analytical and Applied Pyrolysis, 2003), hereinafter ‘Pantea’, in view of Bernardo et. al., “Characterization of chars produced in the co-pyrolysis of different wastes: Decontamination study,” Journal of Hazardous Materials 207–208 (2012) 28–35, hereinafter ‘Bernardo’, and further in view of Larba et.al., “Citric acid as an alternative lixiviant for zinc oxide dissolution”, Hydrometallurgy 134–135 (2013) 117–123 (hereinafter referred to as Larba).
Regarding Claim 15 and 26, Pantea as modified above teaches the method of claim 14, which further requires “wherein the step of selectively extracting zinc is performed using an aqueous solution comprising a carboxylic acid selected from the group consisting of citric acid and tartaric acid”, to which Pantea et al. are silent.
Larba teaches “Zinc is among the most prevalent and valuable metals used in industry. It is widely used as oxide, sulfide, and chloride. The oxide is used in rubber tires, white paint pigment, ceramic glaze, opaque base in cosmetics and in catalysis”; “However, mineral acids cause environmental pollution and may dissolve undesired impurities. Organic acids are not usually used as leechant due to their low dissolution efficiencies, but they are attractive due to the ease of biodegradation. They can be used at mildly acidic conditions (pH 3–5).” ([p. 117, left column]).
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to advantageously modify the method of Pantea as modified above to extract zinc using an acid such as citric acid as disclosed by Larba. The teaching or suggested motivation for doing so being to perform extraction with an acid such as citric acid since it is “attractive due to the ease of biodegradation” (p. 117, Introduction section).
Claim(s) 16 and 27 is/are rejected under 35 U.S.C. 103 as being unpatentable over Pantea et. al. (Heat-treatment of carbon blacks obtained by pyrolysis of used tires. Effect on the surface chemistry, porosity and electrical conductivity, Journal of Analytical and Applied Pyrolysis, 2003), hereinafter ‘Pantea’, in view of Bernardo et. al., “Characterization of chars produced in the co-pyrolysis of different wastes: Decontamination study,” Journal of Hazardous Materials 207–208 (2012) 28–35, hereinafter ‘Bernardo’ and Larba, and further in view of Lou et al., “The influence of acid demineralization on surface characteristics of black carbon and its sorption for pentachlorophenol”, Journal of Colloid and Interface Science 361 (2011) 226–231 (hereinafter referred to as Lou).
Regarding Claim 16 and 27, Pantea as modified above teaches the method of claim 15, which further requires “wherein the aqueous solution comprises hydrofluoric acid in combination with the carboxylic acid selected from the group consisting of citric acid and tartaric acid”, to which Pantea as modified above is silent. Larba teaches the use of citric acid for zinc extraction. Larba does not teach the use of hydrofluoric acid in combination with the carboxylic acid selected from the group consisting of citric acid and tartaric acid.
Lou teaches the effects of acid demineralization, including treatment using HCl or HCl/HCl–HF, on the surface areas, elemental compositions, surface acidity, surface functional groups, and PCP adsorption characteristics of laboratory-produced rice residue chars (prepared under 400 and 600 oC), fly ash, and soot black carbon.” (p. 226, right column); particularly, “[t]o obtain pure BC [(black carbon)] fractions, each source of BC precursors was treated with HCl and HCl–HF” ([p. 227, left column]). Further, Lou shows that samples treated with HCl-HF exhibited vastly improved surface area, pore volume, and mean pore size compared to those samples treated with only HF (Table 2).
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to advantageously modify the method of Pantea as modified above to extract zinc using aqueous solutions of hydrofluoric acid in combination with the carboxylic acid selected from the group consisting of citric acid and tartaric acid. The teaching or suggested motivation for doing so being improved surface area, pore volume, and mean pore size, which are advantageous for applications of carbon black such as use as a sorbent (1. Introduction of Lou).
Allowable Subject Matter
Claims 17 and 20 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
The prior art does not disclose or reasonably suggest that the heat treatment of carbon black as claimed takes place at a temperature of 550 to 600 °C. The closest prior art, Pantea, discloses heat treatment occurring at temperatures between 670 and 860 °C, and does not disclose or suggest performing heat treatment at a temperature within the claimed range.
Response to Amendment
The declaration under 37 CFR 1.132 filed 07/13/2026 is insufficient to overcome the rejection of the claims as set forth in the last Office action. To the extent that the arguments may apply to the use of Bernardo as above, the following is set forth.
It is first noted that while an opinion as to a legal conclusion of an expert is not entitled to any weight, the underlying basis for the opinion may be persuasive. In re Chilowsky, 306 F.2d 908, 134 USPQ 515 (CCPA 1962). In assessing the probative value of an expert opinion, the examiner must consider the nature of the matter sought to be established, the strength of any opposing evidence, the interest of the expert in the outcome of the case, and the presence or absence of factual support for the expert’s opinion. Ashland Oil, Inc. v. Delta Resins & Refractories, Inc., 776 F.2d 281, 227 USPQ 657 (Fed. Cir. 1985), cert. denied, 475 U.S. 1017 (1986). See MPEP 716. In the instant case, the interest of the expert in the outcome of the case is of particular relevance, as the declarant is the first named inventor of the instant application.
Particularly, the declaration argues that Bernardo does not qualify as analogous prior art. The expert argues that Bernardo uses a mixed feed containing only 30% tires and is laboratory scale, while the claimed invention is industrial and pertains to exclusively tire-derived carbon black (see dec. at 4-5). These distinctions do not, by themselves, establish Bernardo to be non-analogous art. Bernardo still pertains to inert-atmosphere pyrolysis of a feed containing used tires, production of a carbonaceous char, and solvent extraction of that char. The field-of-endeavor inquiry is not limited to the narrowest end use, scale, or Applicant’s own asserted point of novelty.
The declaration provides comparative data regarding the claimed invention (see dec. at 6-14). The comparative data has been considered but is not dispositive of non-obviousness.
Firstly, the data does not provide evidence of the supposed synergy asserted by applicant. There is not presented any untreated starting material from which to calculate the effects attributable to heat treatment alone, solvent treatment alone, or a combination of heat and solvent treatment. Thus, the declaration may support the conclusion that these treatments combined provide an improvement, but there is no evidence of a synergistic effect wherein the combined effect exceeds that of the separate effects of these treatments.
Secondly, the solvent treatment showings are not commensurate in scope with the claimed invention. At the claimed temperatures, only one solvent has been demonstrated as achieving the desired results (CH2Cl2, DCM), while the instant claim does not require any particular solvent. Comparative Examples 6 and 7 utilize other solvents but utilize temperatures outside the claimed range. Therefore, there is not a reasonable basis to conclude that the unexpected results occur over the entire scope of the claims, which include other solvents such as those utilized in Comparative Examples 6 and 7. As it pertains to Claim 11, there is also no evidence that the unexpected results only occur within the claimed range of solvent polarity.
Thirdly, the heat treatment showings are not commensurate in scope with the claimed invention. The claimed range for treatment temperature is 500 to 750 °C. The comparative examples present data below this range in Comparative Example 7, but there is no example presented showing that the unexpected results do not occur above the claimed range, i.e., at temperatures above 700 °C. Further, Comparative Example 7 changes two variables (the solvent and heat treatment temperature), and therefore it is not possible to attribute the results to either of these variables alone.
For these reasons, absent additional evidence, the arguments provided by the expert are not persuasive.
Response to Arguments
Applicant’s arguments, filed 07/13/2026, are acknowledged.
Applicant’s arguments have been considered and are persuasive – particularly, Applicant’s argument that the combination of Bernardo and Mikulova does not teach heat treatment and subsequent solvent extraction of a carbon black obtained from pyrolysis of used tires as required by the amended claims is persuasive. Therefore, the rejection is withdrawn. However, a new grounds of rejection is set forth above in view of Pantea in view of Bernardo.
To the extent that the remarks reference the arguments made in the declaration, Applicant is directed to the response to amendment above, in which the declaration is addressed.
Conclusion
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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/L.E.L./Examiner, Art Unit 1736
/ANTHONY J ZIMMER/Supervisory Patent Examiner, Art Unit 1736
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