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
This Office action is based on the 18/262830 application originally filed July 25, 2023.
Amended claims 1 and 3-17, filed July 23, 2025, are pending and have been fully considered. Claims 2 and 18 have been canceled.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 July 23, 2025 has been entered.
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) 1 and 3-17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Shea et al. (US 2015/0113862) hereinafter “Shea” in view of Wolf et al. (US 2013/0227878) hereinafter “Wolf”.
Regarding Claims 1, 7, 8, 10 and 13-17
Shea discloses in paragraph 0002, relates to high octane unleaded aviation gasoline fuel, more particularly to a high octane unleaded aviation gasoline having low-oxygen content.
Shea discloses in paragraph 0026, it has been found that it is difficult to produce a high octane unleaded aviation fuel that meet most of the ASTM D910 specification for high octane aviation fuel. In addition to the MON of 99.6, it is also important to not negatively impact the flight range of the aircraft, vapor pressure, temperature profile and freeze points that meets the aircraft engine start up requirements and continuous operation at high altitude.
Shea further discloses in paragraph 0052, at the same time, however, the freeze point of the resultant blend (again measured by ASTM D2386) increases to −12.4° C. The current standard specification for aviation gasoline, as defined in ASTM D910, stipulates a maximum freeze point of −58° C. Therefore, simply replacing TEL with a relatively large amount of an alternative aromatic octane booster would not be a viable solution for an unleaded aviation gasoline fuel. It has been found that branched chain alkyl acetates having an alkyl group of 4 to 8 carbon atoms dramatically decrease the freezing point of the unleaded aviation fuel to meet the current ASTM D910 standard for aviation fuel.
Shea discloses in paragraph 0027, an unleaded aviation fuel composition having a MON of at least 99.6, sulfur content of less than 0.05 wt %, CHN content of at least 97.2 wt %, less than 2.8 wt % of oxygen content, a T10 of at most 75° C., T40 of at least 75° C., a T50 of at most 105° C., a T90 of at most 135° C., a final boiling point of less than 210° C., an adjusted heat of combustion of at least 43.5 MJ/kg, a vapor pressure in the range of 38 to 49 kPa, comprising a blend comprising:
from about 15 vol % to about 40 vol % of toluene having a MON of at least 107;
from about 2 vol. % to about 10 vol. % of toluidine;
from about 30 vol % to about 55 vol % of at least one alkylate or alkylate blend having an initial boiling range of from about 32° C. to about 60° C. and a final boiling range of from about 105° C. to about 140° C., having T40 of less than 99° C., T50 of less than 100° C., T90 of less than 110° C.,
the alkylate or alkylate blend comprising isoparaffins from 4 to 9 carbon atoms, about 3-20 vol % of C5 isoparaffins, about 3-15 vol % of C7 isoparaffins, and about 60-90 vol % of C8 isoparaffins, based on the alkylate or alkylate blend, and less than 1 vol % of C10+, based on the alkylate or alkylate blend; and
at least 8 vol % of isopentane in an amount sufficient to reach a vapor pressure in the range of 38 to 49 kPa;wherein the fuel composition contains less than 1 vol % of C8 aromatics.
Shea discloses in paragraph 0049, there are three isomers of toluidine (C7H9N), o-toluidine, m-toluidine, and p-toluidine. Toluidine can be obtained from reduction of p-nitrotoluene. Toluidine is preferably present in the blend in an amount from about 2% v, preferably at least about 3% v, most preferably at least about 4% v to at most about 10% v, preferably to at most about 7% v, more preferably to at most about 6% v, based on the unleaded aviation fuel composition. Aromatic amine component including toluidine can be present in the fuel composition in an amount from about 2 vol % to about 10 vol % of aromatic amine component. The aromatic amine component contains at least from about 2 vol. %, based on the fuel composition of toluidine The remainder of the aromatic amine component can be other aromatic amines such as aniline.
Shea discloses in paragraph 0056, according to another embodiment a method for operating an aircraft engine, and/or an aircraft which is driven by such an engine is provided, which method involves introducing into a combustion region of the engine and the high octane unleaded aviation gasoline fuel formulation described herein. The aircraft engine is suitably a spark ignition piston-driven engine. A piston-driven aircraft engine may for example be of the inline, rotary, V-type, radial or horizontally-opposed type.
It is to be noted, Shea fails to specifically teach the fuel composition comprises a straight chain alkyl acetate having 4 to 8 carbon atoms and an alcohol having 4 to 8 carbon atoms.
However, it is known in the art for unleaded aviation fuel to contain a straight chain alkyl acetate having 4 to 8 carbon atoms and to contain a branched chain alcohol having 8 carbon atoms, as taught by Wolf.
Wolf discloses in the abstract, corrosion inhibitor additive combinations giving long acting performance in oxygenated gasoline blends comprising either low carbon number (<3) or high carbon number (greater than or equal to 4) alcohols or mixtures thereof and adapted for use in fuel delivery systems and internal combustion engines.
Wolf further discloses in paragraph 0069, another aspect is to provide a method of reducing corrosion in an fuel infrastructure systems comprising the fuel infrastructure system with a fuel composition comprising a fuel blend stock, about 1 to about 85 v/v % oxygenate or mixtures thereof, and an amount of one or more corrosion inhibitors wherein said amount is about 0.5 ptb to about 5 ptb.
Wolf further discloses in paragraph 0089, the term “fuel” as used herein, refers to any material that can be used to generate energy to produce mechanical work in a controlled manner. Examples of fuels include, but are not limited to, biofuels (i.e., fuels which are in some way derived from biomass), gasoline, gasoline subgrades, diesel and jet fuel. It is understood that the specific components and allowances of suitable fuels can vary based on seasonal and regional guidelines.
Wolf further disclose in paragraph 0090, the terms “fuel blend” or “blended fuel” as used herein, refer to a mixture containing at least a fuel and one or more alcohols.
Wolf further discloses in paragraph 0086, the term “alcohol” as used herein refers to any of a series of hydroxyl compounds, the simplest of which are derived from saturated hydrocarbons, having the general formula CnH2n+1OH.
Wolf further discloses in paragraph 0087, “Butanol” as used herein refers with specificity to the butanol isomers 1-butanol (1-BuOH), 2-butanol (2-BuOH), tert-butanol (t-BuOH), and/or isobutanol (iBuOH or i-BuOH or I-BUOH, also known as 2-methyl-1-propanol), either individually or as mixtures thereof. From time to time, when referring to esters of butanol, the terms “butyl esters” and “butanol esters” may be used interchangeably.
Wolf further discloses it is known in the art to mix alcohols as a co-solvent in various fuel compositions, as shown in Table 7 (Octamix #1). Wolf includes the co-solvent includes n-pentyl acetate in the amount of 0.65 volume percent.
It is to be noted, the amount of alkyl acetate and branched alcohol of Wolf overlap the claimed volume ratio of alkyl acetates and branched alcohols of the present invention (2:1 to 1:2).
It would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to add the alkyl acetate and branched alcohols of Wolf to the unleaded aviation fuel composition of Shea. The motivation to do so is to add corrosion inhibited oxygenates (alkyl acetates and alcohols) to a fuel composition in order to aid in corrosion reduction.
Regarding Claim 3
Shea discloses in paragraph 0051, isopentane is present in an amount of at least 8 vol % in an amount sufficient to reach a vapor pressure in the range of 38 to 49 kPa. The alkylate or alkylate blend also contains C5 isoparaffins so this amount will typically vary between 5 vol % and 25 vol % depending on the C5 content of the alkylate or alkylate blend. Isopentane should be present in an amount to reach a vapor pressure in the range of 38 to 49 kPa to meet aviation standard. The total isopentane content in the blend is typically in the range of 14% to 26 vol %, preferably in the range of 12% to 18% by volume, based on the unleaded aviation fuel composition.
Regarding Claim 4
Shea discloses in paragraph 0055, in order to satisfy other requirements, the unleaded aviation fuel according to the invention may contain one or more additives which a person skilled in the art may choose to add from standard additives used in aviation fuel. There should be mentioned, but in non-limiting manner, additives such as antioxidants, anti-icing agents, antistatic additives, corrosion inhibitors, dyes and their mixtures.
Regarding Claims 5 and 9
Shea discloses in paragraph 0043, the adjusted heat of combustion will be at least 43.5 MJ/kg, and have a vapor pressure in the range of 38 to 49 kPa. The high octane unleaded fuel composition will further have a freezing point of −58° C. or less. Further, the final boiling point of the high octane unleaded fuel composition should be less than 210° C measured with greater than 98.5% recovery as measured using ASTM D-86. If the recovery level is low, the final boiling point may not be effectively measured for the composition (i.e., higher boiling residual still remaining rather than being measured). The high octane unleaded aviation fuel composition have a Carbon, Hydrogen, and Nitrogen content (CHN content) of at least 97.2 wt % of oxygen. Suitably, the unleaded aviation fuel have an aromatics content measured according to ASTM D5134 of greater than 15 wt % to about 35 wt %.
Regarding Claim 6
Shea discloses in paragraph 0049, less than 1 vol % of C10+ based on the alkylate or alkylate blend; Alkylate or alkylate blend is preferably present in the blend in an amount from about 30% v based on the unleaded aviation fuel composition.
Regarding Claims 11 and 12
Shea discloses in paragraph 0056, according to another embodiment a method for operating an aircraft engine, and/or an aircraft which is driven by such an engine is provided, which method involves introducing into a combustion region of the engine and the high octane unleaded aviation gasoline fuel formulation described herein. The aircraft engine is suitably a spark ignition piston-driven engine. A piston-driven aircraft engine may for example be of the inline, rotary, V-type, radial or horizontally-opposed type.
Response to Arguments
Applicant's arguments filed July 23, 2025 have been fully considered but they are not persuasive.
Applicants argued: “The Examiner cites Wolf as a document which discloses gasoline compositions containing a straight chain alkyl acetate having 4 to 8 carbon atoms and a branched chain alcohol having from 4 to 8 carbon atoms. However, the person skilled in the art would not have been motivated to combine Shea and Wolf. As explained in our previous response, the main focus of Shea is aviation gasoline for aircraft engines. By contrast, the main focus of Wolf is gasoline for automotive engines. Indeed, there is no mention whatsoever in Wolf of the ASTM D910 specification for aviation gasoline. A person skilled in the art of fuels for aircraft engines would not look to prior art focused on automatic gasoline in order to solve technical problems associated with avgas. Secondly, suitable corrosion inhibitors are already listed in Shea. Hence, starting from Shea, and wanting to prevent corrosion in an avgas formulation, the person skilled in the art would automatically use one or more standard additives already known for use in aviation fuels. They would not have been motivated to consult another document to look for a bespoke solution to the problem of corrosion, especially when that document is focused on automotive fuels. This is especially true in the case of the avgas area which is subject to very strict regulations for aeronautical applications, as explained above.”.
Applicants arguments are not deemed persuasive. First, Wolfe is not relied upon to teach the “intended use” of the claimed unleaded fuel composition but rather known oxygenates that are used in jet fuel compositions (see above and paragraphs 0069, 0086, 0087, 0089 and 0090 of Wolfe). Shea specifically teaches the use of aviation/jet fuel to be used in aircraft, meeting the intended use of claims 10-14 of present invention. Second, corrosion inhibitors are known in the art to be used in various fuel compositions, including aviation/jet fuel, to meet certain ASTM standards, as taught by both Shea and Wolfe. Therefore, it would have been obvious to one of ordinary skill in the art to use the various corrosion inhibitors of Shea and Wolfe in a fuel composition. Therefore, it is maintained Shea and Wolfe have met the limitations of the presently claimed invention.
Applicants argued: “The surprising benefits of the present invention have been demonstrated in the Examples of the present application. In particular, Figure 1 and Tables 6-8 show that the combination of straight chain n-butyl acetate and branched chain isobutyl alcohol exhibited an increase in MON as a 1:1 blend ratio was reached which started dropping again after a 1:3 ratio of n-butyl acetate:isobutyl alcohol was reached. This is in contrast to a combination of a branched chain acetate (isobutyl acetate or t-butyl acetate) and isobutyl alcohol which exhibited a decrease in MON as isobutyl alcohol was added. In addition, Table 9 shows that a 1:1 weight ratio of n- butyl acetate with a branched chain C4-C8 alcohol provided a MON of from 100.1-101.8. Amended Claim 1 has been limited to a volume ratio of straight chain alkyl acetate to branched chain alcohol in the range from 1:2 and 2:1 and is therefore more commensurate in scope with the worked examples.”
Applicants arguments are not deemed persuasive. Applicants argued the examples defined in the specification. The examiner acknowledges these results, however, the examples are insufficient to overcome the above rejection because (1) applicants have not compared the claimed invention to the teachings of the reference and (2) the examples are not commensurate in scope with the claims because the examples are directed to specifics not literally defined by the claims, for example, the examples use specific amounts oxygenates (alkanes and alkylates), a specific co-solvent blend and specific alcohols within certain amounts which are all not commensurate in scope with independent claims 1 and 10 at least. The examples no way allow the examiner to determine a trend for the results for any and all amounts. Evidence of unexpected results must be clear and convincing. In re Lohr 137 USPQ 548. Evidence of unexpected results must be commensurate in scope with the subject matter claimed. In re Linder 173 USPQ 356.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to LATOSHA D HINES whose telephone number is (571)270-5551. The examiner can normally be reached Monday thru Friday 9:00 AM - 6:00 PM.
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/Latosha Hines/Primary Examiner, Art Unit 1771