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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 17 December 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.
Claims 1-7, 9, 10, 13-15 and 17-19 are rejected under 35 U.S.C. 103 as being unpatentable over United States Patent Application Publication No. US 2017/0231088 (hereinafter “Akatuka”), and further in view of WO 2019/203243 A1 with United States Patent Application Publication No. US 2020/0407524 (hereinafter “Kotera”) being used as the English language equivalent translation.Regarding claims 1 and 18 Akatuka teaches a double-sided circuit substrate comprising a laminate of: a copper foil; a glass cloth; and a dielectric fluorine resin film (abstract, and paragraphs [0009] and [0024]), which corresponds to a copper-clad laminate comprising: (i) a copper foil and a fluororesin film; or (ii) a copper foil, a fluororesin film, and a layer other than the copper foil or the fluororesin film, wherein the fluororesin film: consists essentially of a fluororesin; and is a film comprising a fluororesin-containing composition. Akatuka teaches the fluorine resin film is preferably surface modified for enhancing the adhesive properties (paragraph [0040]), which corresponds to the fluororesin film having a surface that is modified. Akatuka teaches the surface (state of one or both surfaces of the film) of the fluorine resin has an abundance ratio of oxygen atom (oxygen element percentage) being at least 1.0% (atom%), or preferably 2.5% (atom%) or more, as observed using ESCA (abstract, and paragraphs [0014] and [0043]), which encompasses/falls within the claimed ranges. The limitation “an oxygen element percentage as measured when heat treatment is performed at 180°C for 3 minutes and then the state of one or both surfaces of the film is observed by scanning X-ray photoelectron spectroscopy (XPS/ESCA)” has been considered. However, the manner in which the test is performed to measure the oxygen element percentage of the film does not appear to imply any further structure to the claimed film; therefore, at least this part of the claim has been found to be present from Akatuka’s teachings. Akatuka teaches the double-sided circuit substrate exhibits excellent dimensional stability (paragraphs [0001] and [0009]). Akatuka does not explicitly teach: (1) an absolute value of a rate of dimensional change in MD and TD before and after heat treatment as measured when the film is heat-treated at 180°C for 10 minutes and then cooled to 25°C is 2% or less; and (2) the one or both surfaces of the film are annealed surfaces. Furthermore, with regards to optional element (ii) from claim 1, Akatuka also does not explicitly teach (3) the double-sided circuit substrate (copper-clad laminate) comprises a layer other than the copper foil or the fluororesin film, where the layer other than the copper foil or the fluororesin film is at least one selected from the group consisting of polyimide, liquid crystal polymer, polyphenylene sulfide, a cycloolefin polymer, polystyrene, epoxy resin, bismaleimide, polyphenylene oxide, polyphenylene ether and polybutadiene. Kotera teaches a roll film comprising a fluororesin, and a copper-clad laminate made from the roll film (abstract and paragraph [0014]). Kotera teaches in the roll film, an absolute value of the dimensional change rate in each of MD and TD is less than 1.0%, which falls within the claimed range, when heated at 150°C for 30 minutes and then cooled to 25°C (before and after heat treatment) (paragraph [0081]). Kotera teaches, when compared to conventional fluororesins, the dimensional change rate of a roll film in each of MD and TD is suppressed within a predetermined range, and the electrolytic corrosion is suppressed, by controlling the thickness of the film of a fluororesin and the after-mentioned annealing treatment conditions (one or both surfaces of the film are annealed surfaces) (paragraph [0082]). Kotera also teaches the dimensional change rate is measured at the time of the annealing treatment (paragraph [0111]). Kotera teaches the untreated film has each of change rate MD and change rate TD of higher than 1.0% (paragraph [0094]). Kotera teaches the specific temperature for the annealing treatment is at least the glass transition temperature of the fluororesin +10°C and at most the melting temperature of the fluororesin -20°C, and in the case of normal fluororesins (PFA having a melting temperature of from 260 to 320°C), it is 80 to 300°C (paragraph [0095]), which encompasses the claimed range (of the claimed film being heat-treated at 180°C). Kotera teaches the time for the annealing treatment may be appropriately set considering the desired dimensional change rate of the roll film and the temperature of the annealing treatment. The time for the annealing treatment is preferably from 1 to 30 minutes (paragraph [0114]), which encompasses the claimed range (of the claimed film being heat-treated for 10 minutes). Kotera also teaches when the annealing time is at least the lower limit value of the above range, a printed board which is excellent in the stability in the electrolytic corrosion test tends to be obtained from the roll film. When the annealing time is at most the upper limit value of the above range, the treatment efficiency is high, and a printed board can be industrially easily produced (Id). The limitation “an absolute value of a rate of dimensional change in MD and TD before and after heat treatment as measured when the film is heat-treated at 180°C for 10 minutes and then cooled to 25°C” has been considered. However, the manner in which the film is heated to measure the absolute value of a rate of dimensional change in MD and TD does not appear to imply any further structure to the claimed film; therefore, at least this part of the claim has been found to be present from Kotera’s teachings. With regards to optional element (ii) from claim 1, Kotera teaches in a case where the annealing treatment is carried out under applying tension to the untreated film, it is preferred that another substrate (layer other than the copper foil or fluororesin film) is laminated on the untreated film prior to the annealing treatment, where the another substrate may be a resin film (paragraphs [0118] and [0119]). Kotera teaches the resin constituting the resin film includes a non-fluororesin where polyimide is provided as an example (paragraph [0120]). Kotera teaches a more detailed list of non-fluororesin or a resin containing no fluorine atom comprising, as examples, polyimide, polyphenylene sulfide, polystyrene, epoxy resin, polyphenylene ether, etc. (paragraph [0070] and [0072]). Akatuka and Kotera are analogous inventions in the field of dielectric fluororesin films useful in copper-clad laminates. It would have been obvious to a person having ordinary skill in the art at the time of the invention to modify the fluorine resin film of Akatuka with the desired dimensional change rate (of less than 1%) of Kotera by setting the time for the annealing treatment (heat-treatment) of the film by considering the desired dimensional change rate of the roll film and the temperature of the annealing treatment to yield a printed circuit board made from the fluororesin film exhibiting a balance between: excellence in the stability in the electrolytic corrosion test; and high treatment efficiency permitting an industrial scale production of said printed board to be easily produced.Alternative analysis: Regarding the measurements for the oxygen element percentage and the absolute value of a rate of dimensional change in MD and TD, although the prior art does not explicitly disclose: (1) an oxygen element percentage as measured when heat treatment is performed at 180°C for 3 minutes and then the state of one or both surfaces of the film is observed by scanning X-ray photoelectron spectroscopy (XPS/ESCA) is 1.35 atom% or more; and (2) an absolute value of a rate of dimensional change in MD and TD before and after heat treatment as measured when the film is heat-treated at 180°C for 10 minutes and then cooled to 25°C is 2% or less, the claimed properties are deemed to naturally flow from the structure in the prior art since the combination of Akatuka and Kotera teaches an invention with an identical and/or substantially identical structure and/or chemical composition as the claimed invention. See MPEP §2112.Regarding claims 2 and 17 As previously mentioned, Akatuka teaches the surface of the fluorine resin has an abundance ratio of oxygen atom (oxygen element percentage) being at least 1.0% (atom%) (abstract, and paragraphs [0014] and [0043]), which encompasses the claimed ranges.Regarding claim 3 In addition, Akatuka teaches the fluorine resin is preferably tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA), tetrafluoroethylene-hexafluoropropylene (FEP), etc. (paragraph [0023]).Regarding claim 4 In addition, Akatuka teaches two different PFA films having an abundance ratio of O (oxygen atom) of 2.62% on the surface measured by ESCA surface analysis (paragraph [0065]). Regarding a difference of oxygen element percentages when measured under different conditions, although the prior art does not explicitly disclose a difference between an oxygen element percentage measured when the state of one or both surfaces of the film is observed by scanning X-ray photoelectron spectroscopy (XPS/ESCA) and an oxygen element percentage measured by scanning X-ray photoelectron spectroscopy (XPS/ESCA) after etching the film by argon gas cluster ion beams at an incident angle of 45° in the direction of the depth for 15 minutes is 1.0 atom% or more, the claimed properties are deemed to naturally flow from the structure in the prior art since the combination of Akatuka and Kotera teaches an invention with an identical and/or substantially identical structure and/or chemical composition as the claimed invention. See MPEP §2112.Regarding claim 5 In addition, Akatuka teaches a peel strength (adhesion strength) between the copper foil and the fluorine resin film of 0.8 N/mm (800 N/m) (paragraph [0016]), which falls with the claimed range. The use of product-by-process limitations has been noted in claim 5, for example, "surfaces of the film are mutually bonded at 200°C". "[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process", In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985). Further, "although produced by a different process, the burden shifts to applicant to come forward with evidence establishing an unobvious difference between the claimed product and the prior art product", In re Marosi, 710 F.2d 798, 802, 218 USPQ 289, 292 (Fed. Cir.1983). See MPEP § 2113. Regarding claims 6 and 7 In addition, Akatuka teaches the fluorine resin is preferably one of PFA and FEP from the viewpoint of desired electric characteristics (permittivity and dielectric loss tangent), heat resistance, etc. (paragraph [0024]). Akatuka teaches a dielectric loss tangent, measured at 20 GHz, is 0.0014 (Table 1 and paragraph [0070]).
Regarding the dielectric loss tangent of the fluororesin film, although the prior art does not explicitly disclose the fluororesin film has a dielectric loss tangent at 10 GHz or 40 GHz of less than 0.0015, the claimed properties are deemed to naturally flow from the structure in the prior art since the combination of Akatuka and Kotera teaches an invention with an identical and/or substantially identical structure and/or chemical composition as the claimed invention. See MPEP §2112.Regarding claim 9 In addition, Akatuka teaches a peel strength (adhesion strength) between the copper foil and the fluorine resin film of 0.8 N/mm (paragraph [0016]). Akatuka teaches an embodiment where the copper foil is an electrolytic copper foil named CF-T9DA-SV-18, made by Fukuda Metal Foil & Powder Co., Ltd. (paragraph [0065]), which is identical to a copper foil disclosed by the applicant as being commercially available and having a surface roughness Rz of 0.85 µm (see paragraph [0087] from the Pre-Grant publication of the instant application (US 2023/0363090)).Regarding claim 10 In addition, Akatuka teaches the fluorine resin film is included in a double-sided circuit substrate, where said double-sided circuit substrate comprises a laminate of: a copper foil; a glass cloth; and the fluorine resin film (abstract, and paragraphs [0009] and [0024]), which corresponds to a copper clad laminated board. Kotera also teaches a copper-clad laminate is made from the roll film of fluororesin (abstract and paragraph [0014]).Regarding claim 13 In addition, Akatuka teaches an embodiment where the copper foil is an electrolytic copper foil named CF-T9DA-SV-18, made by Fukuda Metal Foil & Powder Co., Ltd. (paragraph [0065]), which is identical to a copper foil disclosed by the applicant as being commercially available and having a surface roughness Rz of 0.85 µm (see paragraph [0087] from the Pre-Grant publication of the instant application (US 2023/0363090)).Regarding claim 14 In addition, Akatuka teaches a peel strength (adhesion strength) between the copper foil and the fluorine resin film of 0.8 N/mm (paragraph [0016]).Regarding claim 15 In addition, Akatuka teaches the laminate (copper clad laminate) is provided in a double-sided circuit substrate (abstract and paragraphs [0010] – [0018]). Kotera also teaches a printed board (substrate for circuit) is made from the copper-clad laminate (abstract and paragraph [0014]).Regarding claim 19 In addition, Akatuka teaches the surface modification of the fluorine resin film includes graft polymerization of a polymerizable organic compound (paragraph [0040]).
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Akatuka and Kotera as applied to claim 1 above, and further in view of United States Patent Number 4,743,658 (hereinafter “Imbalzano”).Regarding claim 8 The limitations for claim 1 have been set forth above. In addition, the combination of Akatuka and Kotera does not explicitly teach the number of unstable terminal groups is less than 10 per 106 carbon atoms in a main chain of the fluororesin. Imbalzano teaches a fluororesin substantially free of unstable end (terminal) groups and extractable fluoride that cause corrosion of metal surfaces (abstract). Imbalzano teaches the selections of the initiator and chain transfer agent dictates the end groups on the polymer chain, where unstable end groups evolve HF and has been found to be corrosive to metals, where reducing the number of the unstable end groups yields a fluororesin which is thermally stable and chemically inert (column 1, lines 36-68 and column 2, lines 3-9). Imbalzano teaches fluorination of the polymer reduces the number of the unstable end groups (column 3, lines 3-13). Imbalzano teaches after the fluorination treatment, the fluororesin will contain a number of unstable end (terminal) groups of less than 6 per 106 carbon atoms in the polymer chain (column 4, lines 22-25), which falls within the claimed range. Akatuka, Kotera, and Imbalzano are analogous inventions in the field of fluororesin compositions. It would have been obvious to a person having ordinary skill in the art at the time of the invention to modify the fluororesin from the combination of Akatuka and Kotera with the reduced number of unstable end (terminal) groups of Imbalzano to improve the thermal stability and/or chemical inertness of the fluororesin.
Claim 16 is rejected under 35 U.S.C. 103 as being unpatentable over Akatuka and Kotera as applied to claim 1 above, as further evidenced by a material data and safety sheet titled “(POLY[TETRAFLUOROETHYLENE-CO-PERFLUORO (ALKYL VINYL ETHER)]) Product Description” obtained from chemicalbook.com (hereinafter “CB”).Regarding claim 16 The limitations for claim 1 have been set forth above. In addition, Akatuka teaches a method of making the composite laminate (copper-clad laminate) of the copper foil comprises: preparing, under heat (preheating), a melted product of the fluorine resin; and pressure-bonding the fluorine resin with the copper foil (paragraph [0045]). Akatuka teaches to prevent oozing (resin in a melted state), the pressure bonding under heat can be carried out in the range of 250 to 330°C (paragraph [0046]). Akatuka teaches the fluorine resin is preferably tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA) (paragraph [0023]). As evidenced by CB, the melting point of tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA) is 305°C (page 2). The temperature of the pressure bonding ranging from 250-330°C and the melting point of PFA being 305°C correspond to an embodiment which meets the claimed limitation requiring the preheating of the fluororesin film to be performed at the glass transition temperature or more and less than the melting point of the film.
Response to Arguments
Two different sets of remarks/arguments are noted, filed 17 December 2025 and 29 January 2026. The most recent set of remarks/arguments are directed to the current set of claims. There does not appear to be any remark/argument in the 17 December 2025 submission, which is commensurate in scope with the instant claims, and is not presented in the remarks/arguments in the 29 January 2026. Therefore, the examiner’s response to the 29 January 2026 set of remarks/arguments is considered to be applicable to both sets of remarks/arguments.
Applicant's arguments filed 29 January 2026 have been fully considered but they are not persuasive.
The applicant argued Akatuka does not disclose or suggest “a fluororesin film consisting essentially of a fluororesin and having a surface that is modified” as required by claim 1 because Akatuka teaches a surface-treated fluorine resin film cannot sufficiently adhere itself to a copper foil having low surface roughness, so Akatuka’s requirement of using a glass cloth is considered an essential component to improve peel strength and achieve low transmission loss, which is precluded from the language of the claim. The examiner respectfully disagrees. First, the transitional phrase “consisting essentially of” limits the scope of a claim to the specified materials or steps "and those that do not materially affect the basic and novel characteristic(s)" of the claimed invention. In re Herz, 537 F.2d 549, 551-52, 190 USPQ 461, 463 (CCPA 1976). In the instant case, when determining materials that would materially affect the basic and novel characteristic(s) of the claimed invention, i.e., materials which are to be excluded from the claim, the applicant’s disclosure must indicate what the basic and novel characteristics actually are. The instant specification fails to provide any information in this regard. Therefore, for the purposes of searching for and applying prior art under 35 U.S.C. 102 and 103, absent such a clear indication in the specification or claims of what the basic and novel characteristics actually are, "consisting essentially of" will be construed as equivalent to "comprising." See, e.g., PPG, 156 F.3d at 1355, 48 USPQ2d at 1355. See also MPEP §2111.03(III). Second, the glass cloth from Akatuka is actually a completely different element when compared to the fluorine resin film. That is, Akatuka teaches a laminate comprising a composite material of sheets of fluorine resin films and sheets of glass cloth(s) alternatively laminated (abstract and paragraph [0010] – [0013]+ and [0048]), which establishes a stack of different materials. Therefore, the glass cloth(s) of Akatuka is not an constituent part of the fluorine resin film; but rather, a different element altogether. In conclusion, it is the position of the examiner that Akatuka does not teach away from “a fluororesin film consisting essentially of a fluororesin,” contrary to the position taken by the applicant. Third, with regards to the “fluororesin film … having a surface that is modified,” the examiner notes this limitation is explicitly recited in Akatuka. Please see the updated rejection of record.
Conclusion
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/BRIAN HANDVILLE/Primary Examiner, Art Unit 1783
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