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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 December 19, 2025 has been entered.
Claims 1-5, 7-20, and 22 are currently pending in the above identified application.
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.
Claims 1-5, 7-20, and 22 are 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.
Specifically, the limitation (A) “wherein the fibers of the thermal insulation and fire protection felt are fiber untreated with chemical flame retardant” in claims 1, 16, and 18, the limitation (B) “wherein the organic fibers constitute at least 60% by weight of the thermal insulation and fire protection felt” in claim 1, the limitation (C) “wherein at least a portion of: the PAN fibers and the PPS fiber constitute at least 60% by weight of the thermal insulation and fire protection felt” in claim 16 and 18, and the limitation (D) “wherein the thermal insulation and fire protection felt lacks chemical flame retardants” in claim 22.
Regarding the limitations (A), Applicant points to para 0001-003 and 0020 as providing support for the amendment. However, para 0020 teaches “[t]he fibers 120 may be made from a thermoplastic resin that is both resistant to heat and burning, such as PPS, polyester, such as homopolymer polyester, bicomponent polyester, or a blend of any of the fibers previously mentioned. Any of the fibers 120 may be further treated with flame-retardant as desired depending on the proportion of fibers 120 to oxidized PAN fibers 110.” Examiner agrees that this portion supports the fibers 120 from being untreated and the fibers 120 encompasses thermoplastic resin fibers. The disclosure discusses fibers 110 mainly in context as being PAN fibers but teaches in para 0025 that “the oxidized PAN fibers 110 may be substituted with another fire-blocking fibrous material, such as glass fibers, silica fibers, ceramic fibers, and/or basalt fibers.” The disclosure is silent with regards to the treatment or lack of treatment of the fibers 110. Therefore, the fibers 110, which encompasses the PAN fibers as well as the inorganic fibers, being untreated with chemical flame retardants is outside the scope of the originally filed disclosure and therefore introduces new matter.
Regarding the limitations (B) and (C), upon further review, these limitations are not support by the originally filed disclosure. These limitations were introduced in the amendments filed September 25, 2024. The originally filed disclosure teaches “[t]he oxidized PAN fibers 110 and PPS fibers 120 may also be substituted with other types of fibers having similar properties without departing from the scope of the present subject matter. In an example, the oxidized PAN fibers 110 may be substituted with another fire-blocking fibrous material, such as glass fibers, silica fibers, ceramic fibers, and/or basalt fibers, which may be associated with various health, safety, and handling constraints. …Utilizing inorganic fibers, such as the glass fibers, silica fibers, ceramic fibers, basalt fibers, and/or other organic fibers may improve the high-temperature resistance of the thermal insulation and fire protection felt 100 and/or reduce mass loss during exposure to high temperatures. On the other hand, limiting the inorganic fibers to a maximum of 40% by weight may reduce or eliminate the health and safety risks associated with these fibers when used in greater proportions, including reducing the irritation risks and/or inhalation risks.” The originally filed disclosure teaches limiting the inorganic fibers to be 40% by weight. Based upon the definition of inorganic fiber and organic fibers, fibers are either inorganic or organic. Therefore, based on the fiber blend, or weight of the fibers in the felt, the organic fiber would necessarily be at least 60% by weight of the total fiber weight. However, the claimed limitation recites “by weight of the thermal insulation and fire protection felt.” The felt is not limited to only being the organic and inorganic fibers and is open to coatings, non-fiber binders, and/or other additive or processing aid, including fillers. Therefore, the originally filed disclosure does not support the organic fiber or specifically the PAN and PPS fibers, being at least 60% by weight of the felt. The scope is further confused with the inclusion “at least a portion of” in claim 16 which is not explicitly taught in the originally filed disclosure and further deviates from the teachings found in the originally filed disclosure.
Regarding the limitation (D), as discussed in the Office Action mailed September 23, 2025, there is no explicitly teaching. Additionally, the full scope of the claim does not appear supported. Limiting the thermoplastic resin fibers, or specifically the PPS fibers, to being untreated with chemical flame retardants is supported. However, the felt lacking chemical flame retardants is not. Para 0001 is in the background section and states “[i]nsulation materials may be manufactured using processes that cause the materials to exhibit undesirable properties, such as increased smoke and flammability when exposed to high temperatures. To counteract these properties, flame-retardant chemicals may be introduced, which may increase the costs of manufacturing due in part to the chemicals needed, as well as the associated application and drying costs.” This portion is specific to manufacturing processes that cause undesirable properties in the materials and is not discussed with regards to the instant invention as well as the scope of flame retardant chemical. This portion broadly and generally discusses insulation material in general, not specifically a felt or the instant invention, that would support the full breadth of the thermal insulation and fire protection felt lacking chemical flame retardant. Applicant points to the teachings of para 0003 stating “these desirable characteristics may be achieved without incurring the additional costs associated with the corrective or counteractive procedures of the prior.” The specifics of these corrective and counteractive procedures are not discussed. The totality of the scope of the amended claims are not supported, especially based on the argued interpretation and scope. PPS is an inherently flame retardant material, however, it’s use as a fiber is explicitly taught and claimed. Therefore the scope of what is considered “chemical flame retardant” is not clear nor readily understood.
To overcome this rejection, applicant may attempt to demonstrate that the original disclosure establishes that he or she was in possession of the amended claims, modify these limitations to align with the scope of the originally filed disclosure, or remove these limitations. For limitations (A) and (C), limiting the plurality of melted thermoplastic resin fibers to being untreated with chemical flame retardants or limiting the plurality of thermoplastic polyphenylene sulfide (PPS) fibers to being untreated with chemical flame retardants would align the scope with the originally filed disclosure. For limitation (B), amending the claim to be based upon the weight percentage of the total weight of the fiber or limiting the felt to consisting of only the recited elements, would align the scope of the claimed with that found in the originally filed disclosure.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-5, 7-20, and 22 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claims 1, 16, and 18, recite the limitation “wherein the fibers of the thermal insulation and fire protection felt are fibers untreated with chemical flame retardants.” It is unclear what is being referenced by “the fibers of the thermal insulation and fire protection felt.” For example, the mechanically entangled oxide polyacrylonitrile (PAN) precursor fibers and/or the thermoplastic polyphenylene sulfide (PPS) fibers? All fibers of the felt? All fibers of the nonwoven felt?
Claims 16 and 18 recite the limitation “wherein at least a portion of: the PAN fibers and the PPS fiber, constitute at least 60% by weight of the thermal insulation and fire protection felt.” It is unclear what is meant by “at least a portion of” and how it is intended to limit the PAN fiber and the PPS fiber constituting at least 60% by weight of the thermal insulation and fiber protection felt. As the limitation set a floor, amounts above 60% are within a scope. Is the limitation directed to a portion of the felt having at least 60% by weight of the PAN fiber and the PPS fiber but allows lower percentage portion in a different portions of the felt, such that the amount of the PAN fiber and PPS fiber may vary? If intended to limit the overall weight of the PAN fibers and the PPS fibers, the limitation “wherein the PAN fibers and the PPS fiber constitute at least 60% by weight of the thermal insulation and fire protection felt” would capture this interpretation.
Claim 22 recites the limitation “lacks chemical flame retardants.” Remarks filed September 25, 2024, that “lacks chemical flame retardants” refers to the “absence of chemicals that are flame retardant.” Based on this definition, materials, or fibers, that are inherent flame retardant would fall under this umbrella and would exclude polyphenylene sulfide. Polyphenylene sulfide is known to be inherent flame-retardant as evidence by US Pub. 2006/0068675 to Handermann (Handermann, para 0029, claim 3) and US Pub. No. 2006/0093870 to Davis (Davis, para 0023), and USPN 5,043,207 to Donovan (Donovan, col. 3 lines 22-31). But PPS is required and positively recited in claim 18, upon which claim 22 depends. If the presence of PPS is excluded, claim 22 would be an improper dependent claim. In Applicant’s remarks filed June 3, 2025, argues that the fibers are PPS and therefore not something added to the fibers but what the fibers are. However, in arguments with regards to the application of Wu, Applicant argues that the addition the fluoropolymer binder would disqualify as lacking added chemical flame retardants since a fluoropolymer are inherently flame-retarded materials. However, the fluoropolymer is added as a binder and not a separate entity purely for increasing or improving the flame retardant properties of the nonwoven. In a similar vein as the PPS fibers, it would not be a material added to nonwoven felt process but parts of the nonwoven itself. Therefore it is not clear what is intended to be include and excluded by the recitation “the thermal insulation and fire protection felt lacks chemical flame retardants added to the nonwoven felt formation.” Are chemicals added specifically for the sole purpose of imparting flame retardant properties intended to be exclude but material added for nonwoven structural or additional purposes allowed? For the purpose of prior art application, Examiner will interpret the limitation as excluding the addition of chemicals for the sole purpose of imparting flame retardant properties and having no additional function or purpose.
The remaining claims are rejected based on their dependency on rejected claims.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1-5, 7, 11, 15-16, 18, and 22 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by US Pub. No. 2022/0042221 to Wu.
Regarding claims 1-5, 7, 11, 15-16, 18, and 22, Wu teaches a nonwoven fabric (thermal insulation and fire protection felt) comprising a plurality of randomly oriented fiber including at least 60% by weight of oxidized polyacrylonitrile fiber (oPAN) (claim 2) and less than 40% by weight reinforcing fiber that have an outer with a melting temperature from 100°C to 450°C bonded together (Wu, abstract, para 0009-0010, 0030, 0047, 0084), reading on at least a portion of the nonwoven mechanically entangled fiber comprising organic fibers constituting at least 60% by weight of the thermal insulation and fire protection felt. Wu teaches UL-94V0 being a flame test used to determine flame retardancy, which is required to EV battery insulation materials (thermal insulation and fire protection felt) (Id., para 0008). Wu teaches the nonwoven having entangled region where two or more discrete fiber have become twisted together or intertwined (Id., para 0040-0041), reading on a plurality of mechanically entangled fibers bonded together. Wu teaches the reinforcing fibers including binder fiber that melt and can be monocomponent including polyphenylene sulfide (claim 3) or polyethylene terephthalate (polyester, claim 4) (Id., para 0048, 0084), reading on a plurality of melted thermoplastic resin fibers. Wu teaches melting refers to transformation of the fiber that becomes sufficiently soft and tacky to bond other fibers in which it comes into contact, including oxidized polyacrylonitrile fiber and other binder fibers that increase the structural integrity in the insulator by creating a three-dimensional array of nodes where the fibers are physically attached to each other (Id., para 0049-0052), reading on the plurality of melted thermoplastic resin fibers, specifically melted thermoplastic polyphenylene sulfide fiber, forming a matrix of bond points between individual fibers of the plurality of mechanically entangled fibers. Wu teaches the nonwoven fabric passing the UL-94V0 flame test (Id., para 0055, 0062), reading on the thermal insulation and fire protection felt obtaining a V0 rating when subjected to UL94 vertical burn test. Wu does not teach the nonwoven requiring additional chemical flame retardants (Id., all, claim 1, para 0084), reading on fibers of the thermal insulation and fire protection felt being fibers untreated with chemical flame retardant (claim 1, 16, and 18), as best understood by Examiner, and the thermal insulation and fire protection felt lacking chemical retardants (claim 22). Examiner will note that the fluoropolymer serves as a binder and not for the sole purpose of imparting flame retardant properties. Wu teaches the fibers being a mixture and shown as homogenous (Id., para 0011, Fig. 2), reading on the plurality of melted thermoplastic resin fibers being homogenously mixed with the plurality of mechanically entangled fibers and being a single homogenous layer constituting the nonwoven.
Regarding claim 5, Wu teaches an embodiment comprising two nonwoven blended web formed of 90% by weight oPAN and 10% of polyester bicomponent laminated to two sides of a 5 mm thick web formed of 80% wt oPAN and 20% of the polyester fiber (Id., para 0079-0085, Table 1), reading on first and second layer each comprising the thermal insulation and fire protection felt with a scrim disposed between.
Regarding claim 7, Wu teaches the nonwoven fabric being at least 60% wt. oxidized PAN fibers (Wu, abstract), reading on the mechanically entangled fiber comprising a maximum of 40% by weight of a plurality of inorganic fiber and a remaining plurality of organic fibers.
Regarding claim 11, Wu doesn’t teach the nonwoven as being flexible (Wu, all). The prior art combination teaches a thermal insulator comprising a nonwoven of mechanically entangled oxidized polyacrylonitrile boned together with a plurality of melted binder fibers of polyphenylene sulfide and/or polyester homogenously mixed with the entangled oxidized polyacrylonitrile fibers with matrix bond points between the individual fibers and having a V0 rating when subjected to a UL94 vertical burn test suitable for use in vehicle application. While Wu does not explicitly teach the rigidity being in excess of felt consisting of the nonwoven mechanically entangled fibers, the property appears to flow naturally from the teachings of Wu since Wu an invention with a substantially similar structure and chemical composition as the claimed invention. Products of identical structure and composition cannot have mutually exclusive properties. The burden is on the Applicants to prove otherwise.
Regarding claim 15, Wu is silent with regards to the exterior surface of the thermal insulator exhibiting a dielectric strength of 25 to 50 volts per mil. However, the claimed property is deemed to flow naturally from the teachings of the prior art since the prior art combination teaches an invention with a substantially similar structure and chemical composition as the claimed invention. The prior art combination teaches a thermal insulator comprising a nonwoven of mechanically entangled oxidized polyacrylonitrile boned together with a plurality of melted binder fibers of polyphenylene sulfide and/or polyester homogenously mixed with the entangled oxidized polyacrylonitrile fibers with matrix bond points between the individual fibers and having a V0 rating when subjected to a UL94 vertical burn test suitable for use in battery application as a thermal insulator. Products of identical structure and composition cannot have mutually exclusive properties. The burden is on the Applicants to prove otherwise.
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, 10-13, 15-16, 18, and 22 are rejected under 35 U.S.C. 103 as being unpatentable over US Pub. No. 2022/0042221 to Wu, as applied claims 1-5, 7, 11, 15-16, 18, and 22 above.
Regarding claims 1-5, 7, 10-13, 15-16, 18, and 22, in the event it is shown that Wu does not disclose the claimed invention with sufficient specificity, the invention is obvious because Wu discloses the claimed constituents and discloses that they may be used alternatively or in combination. It would have been obvious to one of ordinary skill in the art before the effective filing date to form the nonwoven of Wu wherein a plurality of mechanical entangle fiber, such as oxidized PAN fiber, mixed with melted thermoplastic fibers, including PPS or polyester fibers, as a binder homogeneously mixed with the plurality of mechanically entangled fibers without additional chemical flame retardants, motivated by the desire of using conventionally known and predictably disclose features and chemical material disclosed by Wu without unnecessary additives and by the desire to result in homogenous fusing nonwoven as taught as desirable.
Regarding claims 10 and 12, Wu teaches the reinforcing fiber that including binder fibers being less than 40% by weight (Wu, abstract, para 0048), overlapping with the claimed range of 30% by weight of the thermal insulation and fire protection felt and a portion of the melted thermoplastic resin fibers being 3% by weight of the thermal insulation and fire protection felt. While the reference does not specifically teach the claimed range of 30% and 3%, the disclosed range of the prior art combination overlaps with the instant claimed range. It should be noted that 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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). The existence of overlapping or encompassing ranges shifts the burden to Applicant to show that his invention would not have been obvious. In re Peterson, 315 F.3d 1325, 1330 (Fed. Cir. 2003). Furthermore, it would have been obvious to one of ordinary skill in the art before the effective filing date to adjust, vary, and optimize the amount of fibers, such as within the claimed range, motivated by the desire to successfully practice the invention of the prior art based on the totality of the teachings of the prior art.
Claims 8 and 20 is rejected under 35 U.S.C. 103 as being unpatentable over Wu, as applied to claims 1-5, 7, 10-13, 15-16, 18, and 22 above, in view of WO 2020/023379 to Pyun and WO 2000/050675 to Ball.
Regarding claims 8 and 20, Wu teaches oxidized polyacrylonitrile being available under the tradenames PYRON and PANOX (Wu, para 0029).
Wu is silent with regards to the specific carbon content between 60% and 70% carbon weight (claim 8) comprising a maximum of 40% by weight of inorganic material (claim 20).
However, Pyun teaches a flame retardant article useful as a thermal insulator in battery compartments for electric vehicles comprising oxidized polyacrylonitrile and polyphenylene sulfide (Pyun, abstract, p. 1 lines 4-7, p. 5 lines 7-11, p. 21 lines 14-16). Pyun teaches the oxidized polyacrylonitrile fibers being achieve by first stabilizing the precursor fibers at high temperatures to prevent melting or fusion of the fibers, carbonizing the stabilized fibers to eliminate the non-carbon elements, and graphitizing treatment and including PYRON and PANOX (Id., p. 8 line 24-p. 9 line 5). Pyun teaches the fiber being partially to fully oxidized. Ball teaches a carbon fiber from oxidized polyacrylonitrile fiber comprising 76-98%, preferably 85-92% acrylonitrile monomer and 2-24%, preferably 8-15%, polymerized olefinically unsaturated monomers having 60-92% carbon used in high performance composite material (Ball, abstract, p. 3 lines 20-24, p. 4 lines 14-18, p. 9 lines 5-16). Ball teaches that during carbonization, the existing carbo-to-carbon bonds are maintained while new carbon-to-carbon bonds are formed while eliminating oxygen, hydrogen, and nitrogen (Id., p. 9 lines 5-12).
It would have been obvious to one of ordinary skill in the art before the effective filing date to form the thermal insulator of Wu, wherein the carbon content of polyacrylonitrile is 60-92% as taught by Ball and controlled by the processing as taught by Pyun and Ball, motivated by the desire of forming conventionally known oxidized PAN fiber predictably suitable for use in thermal insulator application for electric vehicles and used in high performance applications.
While the reference does not specifically teach the claimed range of 60% to 70% (claim 8) and less than 40% by weight inorganic (claim 20), the disclosed range of the prior art combination overlaps with the instant claimed range. It should be noted that 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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). The existence of overlapping or encompassing ranges shifts the burden to Applicant to show that his invention would not have been obvious. In re Peterson, 315 F.3d 1325, 1330 (Fed. Cir. 2003). Furthermore, it would have been obvious to one of ordinary skill in the art before the effective filing date to adjust, vary, and optimize the carbon content, such as within the claimed range, motivated by the desire to successfully practice the invention of the prior art based on the totality of the teachings of the prior art.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Wu, as applied to claims 1-5, 7, 10-13, 15-16, 18, and 22 above, in view of WO 2020/261012 to Ha and US Pub. No. 2016/0254578 to Gogoro.
Regarding claim 9, Wu teaches the nonwoven fabric being used in battery compartments for electric vehicles (Wu, para 0001).
Wu does not teach the specific structure of the EV battery.
However, Ha teaches nonwoven fabrics being used in in thermal and acoustic insulators in automotive and aerospace applications such as battery compartments for electric vehicles (EVs) (Ha, p. 1 lines 5-6) and that EVs generally have a battery management system that activates an electrical heater if the battery temperature drops significantly below optimal temperatures and activates a cooling system when the battery temperature creeps significantly higher than optimal temperatures (Id., p. 1 lines 34- p. 2 line 2), indicating that high temperatures causes hot gases to occur within the battery compartment Ha teaches the battery being a lithium ion battery (Id., p. 1 lines 35), which are known in the art to comprise lithium batteries deposed within a battery compartment. Ha teaches the thermal insulator being used in compartments for electric vehicles and being disposed within the compartment and teaches that it is desirable for the thermal insulator toe resiliently flex and compress such that it can be easily inserted into irregularly shaped enclosures and expand to occupy fully the space around it (Id., p. lines 2-14). Gogoro teaches a battery compartments with insulating articles (Gogoro, abstract, para 0017-0022). Gogoro teaches a thermal insulating material 26 include materials that have a thermal conductivity that is less than about 0.5 BTU/ft.sup.2/hr/inch at temperatures corresponding to temperatures where the electrical energy storage cells vent and ignition occurs with the pressure relief valve (Id., para 0056-0063, 0084), reading on felt creating a path to divert gases from at least one of the plurality of battery modules to vent the vehicle compartment.
It would have been obvious to one of ordinary skill in the art before the effective filing date to form the EV battery comprising the thermal insulator of Wu, wherein the battery compartment comprising has the structure of Ha and the venting system of Gogoro, motivated by the desire of using conventionally known battery compartment configurations and by the desire to allow venting of gases from the compartment to prevent overheating of the battery.
Claims 14 and 17 are rejected under 35 U.S.C. 103 as being unpatentable over Wu, as applied to claims 1-5, 7, 10-13, 15-16, 18, and 22 above, in view of “Properties, Environmental Stability, and Molding Characteristics of Polyphenylene Sulfide” to Hill.
Regarding claim 14 and 17, polyphenylene sulfide (PPS) is known in the art to have a limiting oxygen index of about 44-46 as shown by Hill and having flame resistant properties (Hill, abstract, Table 1 and 2). It would have been obvious to one of ordinary skill in the art before the effective filing date to form the thermal insulator of Wu, wherein the PPS is the PPS of Hill, motivated by the desire of using conventionally known PPS predictably suitable for use in flame retardant applications.
Claim 19 is rejected under 35 U.S.C. 103 as being unpatentable over Wu, as applied to claims 1-5, 7, 10-13, 15-16, 18, and 22 above, in view of WO 2019/018508 to Bush and USPN 3,513,065 to Pearson.
Regarding claim 19, Wu teaches the nonwoven fabric being attached to one or more acoustically insulating layer (Wu, para 0063).
Wu does not explicitly teach the product further comprising a scrim comprising filament fibers.
However, Bush teaches a nonwoven composite for high temperature application requiring low flammability, smoke and toxicity comprising a fibrous structure having one or more nonwoven material including in a fiber matrix formed from inorganic fibers and fiber blended with the inorganic fiber, specifically oxidized polyacrylonitrile fibers, and high-temperature thermoplastic material binder fibers, including polyphenylene sulfide or polyester (Bush, abstract, para 0028, 0034). Bush teaches the binder fusing the fiber matrix in space (Id., para 0035). Bush teaches the invention passing UL94 V0, including a specific embodiment comprising oxidized PAN fiber with PET bicomponent binder fiber that was lapped (Id., Table 1, para 0070-0082). Bush teaches the fibers of the fiber matrix being blends and the formation of homogenous, short fiber nonwoven (Id., para 0057, 0028, 0039, 0064). Bush teaches the one or more layers including a scrim between two fiber matrix layers or on one side of the nonwoven material layers (Id., para 0047-0049, 0051). Bush teaches the use of a metalize scrim helps to reducing thermal conductivity, which may be due to IR reflection and allow for tuning the material to achieve the desired thermal conductivity based on the application (Id., para 0088). Bush teaches the use of high temperature resistant nonwoven being used to provide structural properties, cushioning, insulation, or sound absorption while still having good fire and smoke retardance and physical strength in a building, vehicle, or aircraft (Bush, para 0001-0002). Additionally, Pearson teaches it is known in fibrous thermal insulation products to use scrim reinforcement of filaments (Pearson, abstract, col. 1 lines 45-63, col. 4 lines 34-39).
It would have been obvious to one of ordinary skill in the art before the effective filing date to form the nonwoven fabric product of Wu, wherein the product further comprises a scrim of filaments as taught by Bush and Pearson, motivated by the desire of using conventionally known materials predictably suitable for use in combination with nonwoven for thermal insulation and to provide reinforcement as well as tunability to achieve the desired properties.
Claims 1-4, 7, 10-12, 15-16, 18, 20, and 22 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/261012 to Ha.
Regarding claims 1-4, 7, 10-12, 15-16, 18, 20, and 22, Ha teaches a first nonwoven fabric 120 (thermal insulation and fire protection felt comprising a nonwoven felt) comprising a plurality of oxidized polyacrylonitrile fibers (mechanically entangled fibers, claim 2) and a plurality of reinforcing fibers including binder fiber that are polymeric (thermoplastic resin fibers, organic fibers) and having entangled regions (mechanically entangled) where two or more discrete fibers have become twisted together (Ha, p. 6 line 9 - p. 7 lines 29), reading on the nonwoven being formed of a plurality of nonwoven mechanically entangled fibers. Ha teaches the nonwoven fabric being made by mixing a plurality of oxidized polyacrylonitrile fibers with a plurality of reinforcing fibers to form a mixture of randomly-oriented fibers and then heated to a temperature sufficient to melt the outer surface of the plurality of reinforcing fibers (plurality of melted thermoplastic resin fibers) (Id., p. 9 line 34- p. 10 line 6), reading on the plurality of nonwoven mechanically entangled fiber being bonded together by a plurality of melted thermoplastic resin binder fibers mixed with the plurality of mechanically entangled fibers (claim 1) and the nonwoven felt being form of a single layer constituting a plurality of nonwoven mechanically entangled oxidized PAN precursor fibers bonded together by a plurality of thermoplastic fibers melted and mixed with the plurality of mechanically entangled PAN precursor fibers (claim 16, 18). Ha teaches the binder fibers create a three-dimensional array of nodes where constituent fibers are physically attached to each other and these nodes provide a macroscopic fiber between which increases tear strength and tensile modulus, preserves dimensional stability of the end product and minimize fiber shedding (Id., p. 8 lines 7-10), reading on the plurality of melted thermoplastic resin fibers forming a matrix of bond points between individual fibers of the plurality of mechanically entangled fibers. Ha teaches the reinforcing fiber include monocomponent fiber and include polyethylene terephthalate (claim 4) and polyphenylene sulfide (claim 3, 16, 18) (Id., p. 7 lines 24-36, p. 9 line 34- p. 10 line 6), reading on a plurality of melted thermoplastic PPS fibers. Ha teaches the oxidized polyacrylonitrile fibers (organic fibers) being present in an amount from 60 wt% to 100 wt% (claim 16, 18) and the reinforcing fibers being present in an amount from 0 wt% to less than 40 wt% (Id., p. 8 lines 24- p. 9 line 8), reading on at least a portion of the nonwoven mechanically entangled fibers and the melted thermoplastic resin fibers including organic fibers and wherein the organic fibers constitute at least 60% by weight of the thermal insulation and fire protection felt (claim 1), as best understood by Examiner, and a maximum of 40% by weight of a plurality of inorganic fibers and a remaining plurality of organic fibers (claim 7, 20). Ha does not require the fibers of the first nonwoven fabric to be treated with chemical flame retardants (Id., all, especially, claims 1-4, p. 9 line 34- p. 10 line 6), reading on the fibers of the thermal insulation and fire protection felt being fibers untreated with chemical flame retardants (claims 1, 16, 18) as best understood by Examiner and the thermal insulation and fire protection felt lacking chemical flame retardants (claim 22). Ha teaches the oxidized polyacrylonitrile fibers to reinforcing fibers bestow both high tensile strength to tear resistance to the nonwoven fabric as well as acceptable flame retardancy, for example the ability to pass the UL-94V0 flame test (Id., p. 9 lines 4-8), reading on the nonwoven being a thermal insulation and fire protection felt and the felt obtaining a V0 rating when subjected to UL94 vertical burn test (claim 1, 18). Ha also teaches the incorporation of binder fibers can allow bulk density to be reduced while preserving structural integrity of the nonwoven fabric, which in turn decreases both weight and thermal conductivity (Id., p. 8 lines 10-12), further reading on the nonwoven being a thermal insulation felt. Ha teaches the nonwoven being used in thermal and acoustic insulators in automotive and aerospace applications such as battery compartments (Id., p. 1 lines 4-8).
While not explicitly teach as having the melted binder fibers being homogenously mixed with the plurality of mechanically entangled oxidized polyacrylonitrile fibers, it would have been obvious to one of ordinary skill in the art before the effective filing date to form the nonwoven insulator of Ha, wherein the binder fibers are homogenously mixed as a to form homogenous nodes within the nonwoven in order to results in uniform and consistent tear strength, tensile modulus, dimensional stability, and fibers shedding which result from the binder fiber melting and bonding the oxidized polyacrylonitrile fibers.
Regarding claims 10 and 12, Ha teaches the reinforcing fiber being 3 wt% to 30 wt% (Ha, p. 8 line 33- p. 9 line 3) overlapping with the claimed range of 30% by weight of the thermal insulation and fire protection felt and a portion of the melted thermoplastic resin fibers being 3% by weight of the thermal insulation and fire protection felt. While the reference does not specifically teach the claimed range of 30% and 3%, the disclosed range of the prior art combination overlaps with the instant claimed range. It should be noted that 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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). The existence of overlapping or encompassing ranges shifts the burden to Applicant to show that his invention would not have been obvious. In re Peterson, 315 F.3d 1325, 1330 (Fed. Cir. 2003). Furthermore, it would have been obvious to one of ordinary skill in the art before the effective filing date to adjust, vary, and optimize the amount of fibers, such as within the claimed range, motivated by the desire to successfully practice the invention of the prior art based on the totality of the teachings of the prior art.
Regarding claim 11, Ha doesn’t teach the first nonwoven as being flexible (Ha, all). The prior art combination teaches a thermal insulator comprising a nonwoven of mechanically entangled oxidized polyacrylonitrile boned together with a plurality of melted binder fibers of polyphenylene sulfide and/or polyester homogenously mixed with the entangled oxidized polyacrylonitrile fibers with matrix bond points between the individual fibers and having a V0 rating when subjected to a UL94 vertical burn test suitable for use in vehicle application. While Ha does not explicitly teach the rigidity being in excess of felt consisting of the nonwoven mechanically entangled fibers, the property appears to flow naturally from the teachings of Wu since Wu an invention with a substantially similar structure and chemical composition as the claimed invention. Products of identical structure and composition cannot have mutually exclusive properties. The burden is on the Applicants to prove otherwise.
Regarding claim 15, Ha teaches the nonwoven providing the combination of low thermal conductivity, small pore size, and high limiting oxygen index (LOI), thus providing good thermal insulation as well as thermal runaway protection for use in battery and having an exterior surface (Ha, p. 5 lines 11-13, p. 5 lines 5-17, Fig. 1), indicating the nonwoven has dielectric strength.
Ha is silent with regards to the exterior surface of the thermal insulator exhibiting a dielectric strength of 25 to 50 volts per mil. However, the claimed property is deemed to flow naturally from the teachings of the prior art since the prior art combination teaches an invention with a substantially similar structure and chemical composition as the claimed invention. The prior art combination teaches a thermal insulator comprising a nonwoven of mechanically entangled oxidized polyacrylonitrile boned together with a plurality of melted binder fibers of polyphenylene sulfide and/or polyester homogenously mixed with the entangled oxidized polyacrylonitrile fibers with matrix bond points between the individual fibers and having a V0 rating when subjected to a UL94 vertical burn test suitable for use in battery application as a thermal insulator. Products of identical structure and composition cannot have mutually exclusive properties. The burden is on the Applicants to prove otherwise.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/261012 to Ha, as applied to claims 1-4, 7, 10-12, 15-16, 18, 20, and 22, in view of WO 2020/023379 to Pyun and WO 00/50675 to Ball.
Regarding claim 8, Ha teaches the polyacrylonitrile fiber comprising carbon and include those available under the tradename PYRON (Zoltek Corporation, Bridgeton, MO) and PANOX (SGL Group, Meitingen, GERMANY) (Ha, p. 5 lines 16-19, Fig. 1).
Ha is silent with regards to the specific carbon content between 60% and 70% carbon weight.
However, Pyun teaches a flame retardant article useful as a thermal insulator in battery compartments for electric vehicles comprising oxidized polyacrylonitrile and polyphenylene sulfide (Pyun, abstract, p. 1 lines 4-7, p. 5 lines 7-11, p. 21 lines 14-16). Pyun teaches the oxidized polyacrylonitrile fibers being achieve by first stabilizing the precursor fibers at high temperatures to prevent melting or fusion of the fibers, carbonizing the stabilized fibers to eliminate the non-carbon elements, and graphitizing treatment and including PYRON and PANOX (Id., p. 8 line 24-p. 9 line 5). Pyun teaches the fiber being partially to fully oxidized. Ball teaches a carbon fiber from oxidized polyacrylonitrile fiber comprising 76-98%, preferably 85-92% acrylonitrile monomer and 2-24%, preferably 8-15%, polymerized olefinically unsaturated monomers having 60-92% carbon used in high performance composite material (Ball, abstract, p. 3 lines 20-24, p. 4 lines 14-18, p. 9 lines 5-16). Ball teaches that during carbonization, the existing carbo-to-carbon bonds are maintained while new carbon-to-carbon bonds are formed while eliminating oxygen, hydrogen, and nitrogen (Id., p. 9 lines 5-12).
It would have been obvious to one of ordinary skill in the art before the effective filing date to form the thermal insulator of Ha, wherein the carbon content of polyacrylonitrile is 60-92% as taught by Ball and controlled by the processing as taught by Pyun and Ball, motivated by the desire of forming conventionally known oxidized PAN fiber predictably suitable for use in thermal insulator application for electric vehicles and used in high performance applications.
While the reference does not specifically teach the claimed range of 60% to 70%, the disclosed range of the prior art combination overlaps with the instant claimed range. It should be noted that 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); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). The existence of overlapping or encompassing ranges shifts the burden to Applicant to show that his invention would not have been obvious. In re Peterson, 315 F.3d 1325, 1330 (Fed. Cir. 2003). Furthermore, it would have been obvious to one of ordinary skill in the art before the effective filing date to adjust, vary, and optimize the carbon content, such as within the claimed range, motivated by the desire to successfully practice the invention of the prior art based on the totality of the teachings of the prior art.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/261012 to Ha, as applied to claims 1-4, 7, 10-12, 15-16, 18, 20, and 22, in view of US Pub. No. 2016/0254578 to Gogoro.
Regarding claim 9, Ha teaches nonwoven fabrics being used in in thermal and acoustic insulators in automotive and aerospace applications such as battery compartments for electric vehicles (EVs) (Ha, p. 1 lines 5-6) and that EVs generally have a battery management system that activates an electrical heater if the battery temperature drops significantly below optimal temperatures and activates a cooling system when the battery temperature creeps significantly higher than optimal temperatures (Id., p. 1 lines 34- p. 2 line 2), indicating that high temperatures causes hot gases to occur within the battery compartment Ha teaches the battery being a lithium ion battery (Id., p. 1 lines 35), which are known in the art to comprise lithium batteries deposed within a battery compartment. Ha teaches the thermal insulator being used in compartments for electric vehicles and being disposed within the compartment and teaches that it is desirable for the thermal insulator toe resiliently flex and compress such that it can be easily inserted into irregularly shaped enclosures and expand to occupy fully the space around it (Id., p. lines 2-14).
Ha fails to explicitly teach a vent to allow hot gases to exit the vehicle battery compartment and the first and second portions of the thermal insulation and fire protection felt create a path to divert hot gases from at least one of the plurality of battery modules to the vent of the vehicle battery compartment.
However, Gogoro teaches a battery compartments with insulating articles (Gogoro, abstract, para 0017-0022). Gogoro teaches a thermal insulating material 26 include materials that have a thermal conductivity that is less than about 0.5 BTU/ft.sup.2/hr/inch at temperatures corresponding to temperatures where the electrical energy storage cells vent and ignition occurs with the pressure relief valve (Id., para 0056-0063, 0084), reading on felt creating a path to divert gases from at least one of the plurality of battery modules to vent the vehicle compartment.
It would have been obvious to one of ordinary skill in the art before the effective filing date to form the EV battery comprising the thermal insulator of Ha, wherein the battery compartment comprising the venting system of Gogoro, motivated by the desire of using conventionally known battery compartment configurations and by the desire to allow venting of gases from the compartment to prevent overheating of the battery.
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/261012 to Ha, as applied to claims 1-4, 7, 10-12, 15-16, 18, 20, and 22, in view of US Pub. No. 2017/0214017 to Pflueger.
Regarding claim 13, Ha teaches the thermal insulator being inserted into irregularly shaped enclosures an fully occupying the space around it (Ha, p. 2 lines 9-16).
Ha does not explicitly teach the insulator being folded in an alternating manner and fastened to itself.
However, Pflueger teaches a battery containing a folded insulation element shown in an alternating manner with attachment sections to insulate adjacent cells (Pflueger, abstract, Fig. 3, para 0026). It would have been obvious to one of ordinary skill in the art before the effective filing date to form the insulator of Ha, wherein the insulator in formed into the configuration of Pflueger, motivated by the desire of forming conventionally known insulator, or insulation element, configurations predictably suitable for use in batteries and to insulate adjacent cells.
Claims 14 and 17 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/261012 to Ha, as applied to claims 1-4, 7, 10-12, 15-16, 18, 20, and 22, in view of “Properties, Environmental Stability, and Molding Characteristics of Polyphenylene Sulfide” to Hill.
Regarding claim 14 and 17, polyphenylene sulfide (PPS) is known in the art to have a limiting oxygen index of about 44-46 as shown by Hill and having flame resistant properties (Hill, abstract, Table 1 and 2). It would have been obvious to one of ordinary skill in the art before the effective filing date to form the thermal insulator of Ha, wherein the PPS is the PPS of Hill, motivated by the desire of using conventionally known PPS predictably suitable for use in flame retardant applications.
Claims 5 and 19 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2020/261012 to Ha, as applied to claims 1-4, 7, 10-12, 15-16, 18, 20, and 22, in view of WO 2019/018508 to Bush and USPN 3,513,065 to Pearson.
Regarding claims 5 and 19, Ha teaches a nonwoven fibrous web (product) comprising a first nonwoven and second nonwoven having the structure of claim 1 bonded together (Ha, abstract, p. 2 lines 23-34; p. 4 line 25-p. 9 line 8). Ha teaches the first nonwoven fabric may optionally include additional layer, such as one or more acoustically insulating layer coupled to the nonwoven fabric (Id., p. 9 line 34- p. 10 line 2).
Ha does not explicitly teach the nonwoven further comprising a scrim disposed between and bonded to the first and second nonwoven fabrics (claim 5) and comprising filament fibers (claim 19).
However, Bush teaches a nonwoven composite for high temperature application requiring low flammability, smoke and toxicity comprising a fibrous structure having one or more nonwoven material including in a fiber matrix formed from inorganic fibers and fiber blended with the inorganic fiber, specifically oxidized polyacrylonitrile fibers, and high-temperature thermoplastic material binder fibers, including polyphenylene sulfide or polyester (Bush, abstract, para 0028, 0034). Bush teaches the binder fusing the fiber matrix in space (Id., para 0035). Bush teaches the invention passing UL94 V0, including a specific embodiment comprising oxidized PAN fiber with PET bicomponent binder fiber that was lapped (Id., Table 1, para 0070-0082). Bush teaches the fibers of the fiber matrix being blends and the formation of homogenous, short fiber nonwoven (Id., para 0057, 0028, 0039, 0064). Bush teaches the one or more layers including a scrim between two fiber matrix layers or on one side of the nonwoven material layers (Id., para 0047-0049, 0051). Bush teaches the use of a metalize scrim helps to reducing thermal conductivity, which may be due to IR reflection and allow for tuning the material to achieve the desired thermal conductivity based on the application (Id., para 0088). Bush teaches the use of high temperature resistant nonwoven being used to provide structural properties, cushioning, insulation, or sound absorption while still having good fire and smoke retardance and physical strength in a building, vehicle, or aircraft (Bush, para 0001-0002). Additionally, Pearson teaches it is known in fibrous thermal insulation products to use scrim reinforcement of filaments (Pearson, abstract, col. 1 lines 45-63, col. 4 lines 34-39).
It would have been obvious to one of ordinary skill in the art before the effective filing date to form the nonwoven fibrous web of Ha, wherein the product further comprises a scrim of filaments as taught by Bush and Pearson between the first and second nonwoven, motivated by the desire of using conventionally known materials predictably suitable for use in combination with nonwoven for thermal insulation and to provide reinforcement as well as tunability to achieve the desired properties. As all the layers are bonded together, the scrim would be bonded to the first and second layers, even with the flame retardant nonwoven fabric between.
Response to Arguments
Applicant's arguments filed December 19, 2025 have been fully considered but are not persuasives with regards to the prior art rejection involving Wu.
Applicant argues, with regards to the application of Wu, that Wu fails to teach wherein the fibers of the thermal insulation and fire protection felt are fibers untreated with chemical flame retardants as Wu teaches a fluoropolymer binder that coats the fibers. Examiner respectfully disagrees. The fluoropolymer is a binder and not a chemical flame retardant treatment. The fiber are not treated with a chemical flame retardant but are bound with a binder that is the fluoropolymer. Examiner would like to highlight that claimed explicitly recites “melted thermoplastic PPS fibers form a matrix of bind points between individual fibers of the plurality of mechanically entangled PAN fibers.” The PPS is a binder. It is also melted and has flame retardancy. If the fluoropolymer binder of Wu were to be considered treating the fiber with a chemical flame retardant, the inclusion of the melted PPS to form bond point, i.e. function as a binder, would also be considered treatment of the PAN fiber with a chemical flame retardant. If the felt were to be limited to consisting of a nonwoven felt formed of a single layer consisting of a plurality of nonwoven mechanically entangled oxidized polyacrylonitrile (PAN) precursor fibers bonded together by a plurality of thermoplastic polyphenylene sulfide (PPS) fibers melted and homogeneously mixed with plurality of mechanically entangled PAN precursor fibers…wherein the plurality of nonwoven mechanically entangled oxidized polyacrylonitrile (PAN) precursor fibers and the plurality of thermoplastic polyphenylene sulfide (PPS) fibers are untreated with chemical flame retardants, the scope of claim would align with no additional materials apart from the recited PAN fibers and the PPS fibers which are untreated with chemical flame retardants and exclude an additional binder, whether inherently having flame retardancy or otherwise.
Examiner would like to note that Ha was previously applied, however, the prior art mapping has been update for the current claim limitations, equating the first or second nonwoven fabric 120 or 130, individually, to the claimed thermal insulation and fire protection felt. As such, the first nonwoven fabric 110 is a nonwoven felt formed of a single layer. The central flame retardant nonwoven fabric is required to have a flame retardant coating , not the first nonwoven fabric 110. The updated mapping address the arguments of the nonwoven being formed of a single layer and being untreated with a fire retardant, as argued in the Remarks filed February 29, 2024 and September 25, 2024.
Conclusion
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/JENNIFER A GILLETT/Examiner, Art Unit 1789
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