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 .
Claims 1-16 are pending as amended on December 11, 2025. Support for amended claim 9 is found in [0027].
Claims 1-8 and 12-16 remain withdrawn from consideration.
The new grounds of rejection set forth below were necessitated by the amendment to claim 9 incorporating an epoxy resin which is a solid at 25 °C. Therefore, this action is properly made final.
Any objections and/or rejections made in the previous Office action and not repeated below are hereby withdrawn. The text of those sections of Title 35, U.S. Code not included in the action can be found in a prior Office action.
Response to Arguments
Applicant’s arguments filed December 11, 2025 with respect to claims 9-11 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
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)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
– (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.
Claim 9 is rejected under 35 U.S.C. 102(a)(1) and 35 U.S.C. 102(a)(2) as being anticipated by Balijepalli (WO 2020167467 A1 and US 2022/0017685 A1 with references made to US 2022/0017685 A1) and evidenced by Clariant (Exolit OP 945 product data sheet, Clariant International Ltd., 2026) and Olin (Epoxy Resins Product Stewardship Manual, Olin Corporation, 2019).
Balijepalli discloses a resin film member comprising a carrier film and a resin layer stacked on the carrier film (film resin coating on the sheet material, [0065]). Balijepalli further discloses that the sheet material (carrier film) can be a release film or paper from which the film coating (resin layer) may be transferred to a fibrous material during the formation of a prepreg article ([0065]) and that prepreg articles can be partially cured ([0069] and [0071]). Because the resin layer is used to make the prepreg articles and the prepreg articles are not fully cured, the resin layer comprised in the resin film member is an un-cured or a semi-cured product of a resin composition.
Balijepalli exemplifies resin compositions in Table II. Inventive Example 2 comprises 31.6 wt.% DEN 438, 30.1 wt.% DER 6508, 16.9 wt.% DER 331, and 9.1 wt.% Exolit OP 945 (Table 2). This composition reads on a resin composition containing a resin component (DEN 438, DER 6508, DER 331, and additional components other than Exolit OP 945) and a phosphorus-containing flame retardant (Exolit OP 945, see Table 1). DER 6508 reads on an epoxy resin which is solid at 25 °C (Table 1 describes DER 6508 as a solid epoxy resin).
Balijepalli is silent as to the viscosities of DEN 438 and DER 331 at 25 °C.
However, DER 438 has a viscosity of 31,000-40,000 mPa-s at 25 °C and DER 331 has a viscosity 11,000-14,000 mPa-s at 25 °C, as evidenced by Olin (Olin, page 7, Table 1). Both DER 438 and DER 331 read on the epoxy resin (a1) because both have viscosities less than 50000 mPa-s. Together, DER 438 and DER 331 account for about 53 wt.% of the resin component ((31.6+16.9)/(100-9.1)=48.5/90.9=0.53).
Balijepalli is silent as to the degradation and melting temperature of Exolit OP 945 and Exolit OP 945 is not one of the Exolit OP flame retardants listed in [0029] of the instant specification.
However, Exolit OP 945 is known to have a degradation point above 300 °C, as evidenced by Clariant (see the table on the first page of Clariant). In addition, there is nothing of record to suggest that the Exolit OP 945 melts at a temperature lower than 150 °C. Exolit OP 945 therefore reads on a phosphorus-containing flame retardant that neither melts nor thermally decomposes at a temperature lower than 150°C.
Claim Rejections - 35 USC § 103
Claims 9-10 are rejected under 35 U.S.C. 103 as being unpatentable over Angus (US 2008/0200084 A1) and evidenced by Olin (Epoxy Resins Product Stewardship Manual, Olin Corporation, 2019).
Regarding claim 9, Angus teaches that combinations of aromatic polymers and epoxy compounds can be made into homogeneous solutions, coated onto substrates, and dried to form tack-free, homogeneous films ([0025]). Substrates taught by Angus include thin dielectric films such as polyimide and polyesters ([0048]), reading on carrier films. Angus teaches that the film-forming solution is cast or coated onto a substrate to form a layer ([0047]) and then heated to remove the solvent, but not substantially cure the film ([0053]). The resulting films can be partially cured B-stage films that have enough mechanical strength for handling, but also have enough unreacted functional sites that they can be further cured to provide the full and final physical polymer properties ([0053]). Such B-stage films read on a resin layer. Angus therefore teaches a resin film member comprising a carrier film (substrate) and a resin layer (B-stage film) stacked on the carrier film and containing a semi-cured product of the resin composition.
Angus teaches that the curable composition contains an epoxy compound, an aromatic polymer, and, optionally, a catalyst, a flame retardant, and/or a filler ([0015]).
As flame retardants, Angus teaches aluminum phosphinate flame retardants under the tradenames EXOLIT OP930 and OP935 from Clariant Corporation ([0044]). These compounds read on a phosphorus-containing flame retardant (B1) that neither melts nor thermally decomposes at a temperature lower than 150°C (see instant specification [0029]).
As a resin component, Angus teaches that the curable composition comprises about 5 to about 50 wt. % of the epoxy compound and about 50 to about 95 wt. % of the aromatic polymer ([0035]). Angus further exemplifies coating compositions comprising both solid and liquid epoxies in Examples 9A-9D of Table 3 where DER 332 is a liquid epoxy and DEN439 is a solid epoxy (Table A). DEN439 is a 50% solution of a solid epoxy in MEK (Table A). The solid epoxy reads on an epoxy resin (a2) which is solid at 25 °C.
Angus teaches that DER332 is a liquid epoxy resin, but is silent as to the viscosity of the resin.
However, prior to the effective filing date of the claimed invention DER332 was known to have a viscosity of 5,000 mPa-s at 25 °C, as evidenced by Olin (Olin, page 7, Table 1). DER332 therefore reads on the epoxy resin (a1) because the viscosity of DER332 is 5,000 mPa-s at 25°C and this viscosity is less than 50000 mPa-s.
The liquid epoxy accounts for 23.9-36 wt. % of the overall composition prior to drying. After drying, the epoxy content from the liquid epoxy of examples 9A-9D would be higher because Table A shows that DER664 is 50% in MEK and ET 001 RJ is 35% in toluene/ethanol. The epoxy content from the liquid epoxy after drying is about 45-60 wt.% (Example 9D’s approximate mass after drying is 100-0.5*16-0.65*59.4= 53.39 and 23.9/53.39=0.45 and Example 9A’s approximate mass after drying is 100-0.5*3.9-0.65*59.6= 59.31 and 36/59.31=0.6).
Angus does not exemplify a resin film member where the resin layer has both the resin component of Examples 9A-9D and an EXOLIT OP930 or OP935 flame retardant.
However, it would have been obvious to one of ordinary skill in the art prior to the effective filing date to have prepared a resin layer using the resin component of Examples 9A-9D and an EXOLIT OP930 or OP935 flame retardant because Angus teaches both components and teaches that flame retardants can be included in the curable composition used to produce the resin film ([0015]). One would further be motivated to include a flame retardant in order to pass the UL 94 vertical burn test with a V-0 or VTM-0 rating ([0044]).
Regarding claim 10, Angus teaches the resin film member of claim 9. Angus does not exemplify a resin layer thickness within the claimed range.
However, Angus teaches that the thickness of the resin film is about 1 to about 100 µm ([0047]). It would have been obvious to one of ordinary skill in the art prior to the effective filing date to have prepared a resin film member with a resin layer thickness of about 1 to about 100 µm because Angus teaches this range. This range overlaps with the claimed range of equal to or greater than 50 µm and equal to or less than 400 µm. It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have selected the overlapping portion of the ranges disclosed by the reference because selection of overlapping portion of ranges has been held to be a prima facie case of obviousness. See MPEP § 2144.05.I.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Angus (US 2008/0200084 A1) and Olin (Epoxy Resins Product Stewardship Manual, Olin Corporation, 2019) as applied to claim 9 above, and further in view of Sato (US 2008/0205019 A1, cited with 9/11/2025 Office action) and Yoo (US 2014/0091296 A1, cited with 9/11/2025 Office action).
Angus teaches the resin film member of claim 9. The resin film member of Angus comprises a resin layer that is a partially cured B-stage film. Angus teaches that after coating the composition, the layer is heated to remove the solvent, but not substantially cure the film ([0053]). The resulting films can be partially cured B-stage films that have enough mechanical strength for handling, but also have enough unreacted functional sites that they can be further cured to provide the full and final physical polymer properties ([0053]). One of ordinary skill would recognize that removing the solvent and partially curing the composition increases the viscosity of the resin layer.
Angus does not teach the melt viscosity of the resin layer at 150°C.
However, prior to the effective filing date, the viscosity of B-stage films was known in the art as a result effective variable in their application as adhesives, as evidenced by Sato and Yoo.
Sato teaches adhesive films (Sato, [0030]) used in circuit boards (Sato, abstract). Sato teaches that the adhesive film preferably has a B-stage viscosity of 100 Pa*s or more and 20,000 Pa*s or less at 200 °C (Sato, [0030]). Sato further teaches that a viscosity of 100 Pa*s or more at 200 °C is desirable for maintaining connection stability, but that if the viscosity of the adhesive film is too high, the resin can hardly be pushed away from between connection parts even when a high pressure is applied (Sato, [0030]).
Yoo teaches adhesive films used in organic electronic devices (Yoo, [0011]). Yoo teaches that a viscosity of 100 to 100000 Pa*s in the temperature range of 30 to 130 °C is desirable in the B-stage to reduce failure and enhance reliability during assembly of panels (Yoo, [0025]). Yoo further teaches that when the viscosity is high enough, the adhesive layer can be leaked 1 mm or less from an original location (Yoo, [0027]), but with the viscosity is too high it is possible to generate unlaminated parts in the adhesive film (Yoo, [0026]).
Based on the disclosures of Sato and Yoo, one of ordinary skill in the art would have recognized that increasing the viscosity improves the stability of the adhesive layer and that decreasing the viscosity improves the ability to avoid unlaminated areas. Therefore, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to have optimized the melt viscosity of the resin layer of Angus into the claimed range of 400 Pa*s or greater at 150 °C. One would have had a reasonable expectation of successfully producing an adhesive resin layer with a balance of stability and complete coverage because Sato and Yoo teach similar viscosities for B-stage adhesive resins in lower and higher temperature ranges, respectively. The discovery of an optimum value of a known result effective variable, without producing any new or unexpected results, is within the ambit of a person of ordinary skill in the art. See In re Boesch, 205 USPQ 215 (CCPA 1980) (see MPEP § 2144.05, II.).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to AUDRA DESTEFANO whose telephone number is (703)756-1404. The examiner can normally be reached Monday-Friday 9-5.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Randy Gulakowski can be reached at (571)272-1302. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/AUDRA J DESTEFANO/Examiner, Art Unit 1766
/RACHEL KAHN/Primary Examiner, Art Unit 1766