DETAILED ACTION
Applicant’s amendment submitted on February 20, 2026 (“amendment”) in response to the Office action mailed on November 28, 2025 (“previous OA”) have been fully considered.
Support for the amendment to claims 1 and 13 can be found in paragraph 0047 of the specification.
In view of the amendment, the objection and the rejection under 35 USC 112(b) as set forth in the previous OA are withdrawn.
In view of the amendment, the art rejections as set forth in the previous OA are modified.
The declaration under 37 CFR 1.132 submitted by Seiji Takagi on February 20, 2026 is not found persuasive, because of the reasons set forth in the current OA (see under “Response to Arguments”).
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.
Claims 1-3, 6, 7, and 10-13 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Ko et al. (WO 2020022799 A1; US 20210238462 A1 is relied upon as English equivalent document in the Office action) and as evidenced by a product data sheet Struktol® Toughener for Reaction Resin Systems.
As to the claimed mass ratio (A1)/(A2) of less than 2.7, this recitation is interpreted as the lower end point of the ratio is slightly more than 0, because claim positively requires the presence of bisphenol-A epoxy resin (A1) and bisphenol-F epoxy resin (A2) (see lines 4-5 of claim 1).
As to the claimed mass ratio (A1)/(A3) of less than 3.0, this recitation is interpreted as the lower end point of the ratio is slightly more than 0, because claim positively requires the presence of bisphenol-A epoxy resin (A1) and a rubber-modified epoxy resin (A3) (see lines 4-5 of claim 1; lines 5-6 of claim 13).
As to independent claim 1, Ko teaches epoxy adhesive (0006). The epoxy adhesive of Ko comprises (a) one or more epoxy resins, (b) a liquid rubber, (c) a core-shell rubber in the form of secondary particles, and (d) one or more epoxy curing agents (curing agent (B)) (0011). Further, Ko teaches that in one example, the adhesive comprises bisphenol A based resin and bisphenol F based resin (0025). Moreover, Ko teaches that the liquid rubber is rubber modified epoxy resin (0036-0040).
Further, as to claim 1, Ko teaches example of epoxy adhesive (Example 3, Table 1) comprising a 10.45 parts by weight of bisphenol-A based epoxy resin (A1) and 25 parts by weight of bisphenol-F-based epoxy resin (A2). Thus, the mass ratio (A1)/(A2) in the epoxy adhesive of Ko is 10.45/25 or 0.42, which is within the claimed range of less than 2.7.
Further, as to claim 1, Ko teaches 10.45 parts by weight of bisphenol-A based epoxy resin (A1) and 20 parts by weight of a Struktol polydis 3604 liquid rubber, (Example 3, Table 1). The examiner submits that Struktol polydis 3604 liquid rubber is nitrile rubber modified epoxy resin (rubber-modified epoxy resin A3) (see page 2 of product data sheet). Therefore, the mass ratio (A1)/(A3) in the epoxy adhesive of Ko is 10.45/20 or 0.52, which is within the claimed range of A1/A3 of less than 3.0.
As to independent claim 13, Ko teaches epoxy adhesive (0006). Ko further teaches a base material and a cured product of the epoxy adhesive applied on the base material (0109). Further, the epoxy adhesive of Ko comprises (a) one or more epoxy resins, (b) a liquid rubber, (c) a core-shell rubber in the form of secondary particles, and (d) one or more epoxy curing agents (curing agent (B)) (0011). Further, Ko teaches that in one example, the adhesive comprises bisphenol A based resin and bisphenol F based resin (0025). Moreover, Ko teaches that the liquid rubber is rubber modified epoxy resin (0036-0040).
Further, as to claim 13, Ko teaches 10.45 parts by weight of bisphenol-A based epoxy resin (A1) and 20 parts by weight of a Struktol polydis 3604 liquid rubber, (Example 3, Table 1). The examiner submits that Struktol polydis 3604 liquid rubber is nitrile rubber modified epoxy resin (rubber-modified epoxy resin A3) (see page 2 of product data sheet). Therefore, the mass ratio (A1)/(A3) in the epoxy adhesive of Ko is 10.45/20 or 0.52, which is within the claimed range of A1/A3 of less than 3.0.
Further, as to claim 13, Ko teaches that the thickness of the adhesive layer was kept uniform at 0.2 mm (0132), which is within the claimed range of 0.1 to 2 mm.
As to claim 2, Ko teaches that an example of liquid rubber having epoxy reactive end group is carboxyl terminated butadiene/acrylonitrile copolymer (0040).
As to claim 3, Ko teaches example of epoxy adhesive (Example 3, Table 1) comprising a 10.45 parts by weight of bisphenol-A based epoxy resin (A1), 25 parts by weight of bisphenol-F-based epoxy resin (A2), and 20 parts by weight of a Struktol polydis 3604 liquid rubber, which is nitrile rubber modified epoxy resin (see page 2 of product data sheet). Accordingly, the amount of the rubber modified epoxy resin with respect to the entire epoxy resin in Ko is (20/(20+10.45+25)) * 100 = 36 wt%, which is within the claimed range of 5-45 mass%.
As to claim 6, Ko teaches dicyandiamide curing agent as an example of the epoxy curing agent (0072).
As to claim 7, Ko teaches core shell rubber particles (minute polymer particles) (0043).
As to claim 10, Ko teaches that the epoxy adhesive is used for bonding metal-plastic (0010).
As to claims 11 and 12, Ko teaches a base material with the epoxy adhesive (0109). Further, as claim 12, Ko teaches that the epoxy adhesive is used for bonding metal-plastic (0010). Additionally, the claim recitation “An adhesive sheet for bonding dissimilar materials”, this recitation is deemed to be an intended use in so far as the structure of the product is concerned. In article claims, a claimed intended use must result in structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. MPEP 2111.02. Given that the adhesive sheet of Ko identical to that of the presently claimed in terms of structure and composition, it meets the intended use of the claimed adhesive sheet (i.e. the adhesive sheet of Ko can be used for bonding dissimilar materials).
Claim Rejections - 35 USC § 102/103
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.
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 8 and 9 are rejected under 35 U.S.C. 102(a)(1) as anticipated by or, in the alternative, under 35 U.S.C. 103 as obvious over Ko et al. (WO 2020022799 A1; US 20210238462 A1 is relied upon as English equivalent document in the Office action) and as evidenced by a product data sheet Struktol® Toughener for Reaction Resin Systems.
As to claim 8, Ko does not explicitly teach whether the adhesive is solid at 25°C. However, where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness is established. MPEP 2112.01 (I). The epoxy adhesive of Ko as set forth previously is identical to the claimed epoxy adhesive (see the rejection of claim 1 over Ko). Further, Ko teaches curing of the adhesive (0011). As such, absent any factual evidence on the record, it would be reasonable to presume that the epoxy adhesive of Ko is inherently solid at 25°C. Alternatively, it would be obvious to arrive at the epoxy adhesive that is solid once the adhesive of Ko is provided so that it can be easily stored.
As to claim 9, Ko is silent as to teaching the viscosity at 60°C as claimed. Ko instead discloses viscosity at 23°C (see 0134 and Table 2). However, as set forth previously, the epoxy adhesive of Ko as set forth previously is identical to the claimed epoxy adhesive (see the rejection of claim 1 over Ko). As such, absent any factual evidence on the record, it would be reasonable to presume that the epoxy adhesive of Ko is inherently has the claimed viscosity.
Alternatively, Ko discloses that in order to apply the adhesive to a base material such as a car frame, a process of applying a constant pressure to the adhesive composition and transferring it is required, and for this purpose, the adhesive should have an appropriate viscosity (0005). Ko further discloses use of diluent to lower the viscosity of adhesive and to improve wettability of the adhesive (0030). Moreover, Ko discloses that when the liquid rubber is used, the viscosity of the adhesive can be properly maintained so that the adhesive can be easily discharged and processability can be improved (0035). It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to select a workable range of the viscosity of the epoxy adhesive in Ko at 60°C using the diluent and liquid rubber and arrive at the claimed viscosity, motivated by the desire to improve wettability of the adhesive and to improve processability of the adhesive.
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.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Ko et al. (WO 2020022799 A1; US 20210238462 A1 is relied upon as English equivalent document in the Office action) and as evidenced by a product data sheet Struktol® Toughener for Reaction Resin Systems as applied to claim 1 above, and further in view of Rinde et al. (US 4507340).
Ko is silent as to disclosing claim 4.
Rinde discloses a curable adhesives comprising (a1) 10-30% of a flexible epoxy resin and (b) 50-90 % of at least one solid epoxy resin having softening point of at least 50°C and epoxy equivalent of least 175 (column 2, lines 5-20). Further, as an example of the solid epoxy resin, Rinde discloses Epon 1001 which is a diglycidyl ether of bisphenol A having a softening point of 65-75°C and epoxy equivalent (EE) of 450-550 (column 3, lines 65-67).
As to claim 4, the examiner submits that a person having ordinary skill in the art would recognize that the epoxy resin Epon 1001 of Rinde is inherently solid at 25°C (softening point 65-75°C) and includes an aromatic ring. Further, a person having ordinary skill in the art would recognize that Epon 1001 is inherently different from the epoxy resins (A1) and (A3) as disclosed by Ko. For example, the EE of Epon1 1001 is 450-550, which is different from the bisphenol A epoxy resin having EE of less than 300 disclosed in the example 3 on Table 1 of Ko, and Epon 1001 is different chemically from the rubber modified epoxy resin disclosed by Ko in Example 3).
Ko discloses that specific structure of the epoxy resin used for the adhesive is not particularly limited (0014). Ko further desires one or more epoxy resins (0011). Moreover, Ko also desires bisphenol A epoxy resin having EE of more than 300 (0022).
It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to select a commercially available epoxy resin such as Epon 1001 having EE of 450-550 disclosed by Rinde and use it to form the epoxy adhesive of Ko, because Ko desires bisphenol A epoxy resin having EE of more than 300. The selection of known material based on its suitability for its intended use supports prima facie case of obviousness. See MPEP 2144.07.
Claims 14 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Ko et al. (WO 2020022799 A1; US 20210238462 A1 is relied upon as English equivalent document in the Office action) and as evidenced by a product data sheet Struktol® Toughener for Reaction Resin Systems as applied to claim 13 above, and further in view of Endo et al. (US 20130109785 A1).
Ko is silent as to disclosing claims 14 and 15.
Endo discloses a thermosetting resin composition and cured product thereof having excellent in adhesiveness with a substrate (0025). The thermosetting resin composition of Endo includes (A) an epoxy resin, (B) a curing agent for the epoxy resin, (C) a spherical silicon dioxide and/or spherical aluminum oxide, and (D) a block copolymer (0025). Further, as to claim 14, Endo discloses that the thermosetting resin composition is impregnated in sheet-like fibrous substrates such as glass and aramid nonwoven fabrics (0125). Further, as to claim 15, Endo discloses that a releasable cover film is applied on the surface of the thermosetting resin composition layer for the purpose of preventing dust from adhering to the surface of the thermosetting resin composition layer (0127).
As to claim 14, Ko discloses that the base material includes glass fiber containing base material (0109). It would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to use a nonwoven fabric and impregnated with the epoxy adhesive, because Ko desires glass fiber containing base material and doing so would be obvious for the purpose of forming the adhesive sheet of Ko.
As to claim 15, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to provide a release film on at least one surface of the adhesive layer in Ko, motivated by the desire to protect the adhesive layer from dust.
Response to Arguments
Applicant's arguments submitted in the amendment have been fully considered but they are not persuasive.
With respect to the rejection of claims 1-3, 6, 7, 10-13 under 35 USC 102(a)(1) as being anticipated by Ko et al. (WO 2020022799 A1; US 20210238462 A1) and as evidenced by a product data sheet Struktol® Toughener for Reaction Resin Systems, applicant argues the following:
The examiner’s calculation of the mass ratio of a bisphenol-A epoxy resin (A1) to a bisphenol-F resin (A1/A2) is incorrect. According to applicant, examiner’s calculation does not take into account the bisphenol A epoxy resin contained in the liquid rubber Struktol polydis 3604 disclosed by Ko in Example 3. Applicant further uses this rationale and calculates mas ratio (A1)/(A3) in Example 3 of Ko as 3.35 to 14.225. Pages 7-8 of the amendment.
The declaration under 37 CFR 1.132 submitted by Seiji Takagi (“Declaration”) is submitted to demonstrate that that when the mass ratio A1/A3 is 3.0 or more, the adhesive becomes rigid, resulting in inferior evaluation of adhesive strength. Pages 1-3 of the Declaration and pages 8-9 of the amendment referring to the Declaration.
The examiner respectfully disagrees.
With respect to (A) above, the examiner submits that applicant’s showing/argument is not commensurate in scope with the claimed invention, because there is nothing in the claims that require that “mass ratio [(A1)/(A2)]” encompasses or based on total mass of all the bisphenol-A epoxy resin(s) in the adhesive. The claims require mass ratio of a bisphenol-A epoxy resin (A1) to a- bisphenol-F epoxy resin (A2) of less than 2.7, and mass ratio of a bisphenol-A-epoxy resin (A1) to a rubber-modified epoxy resin (A3) of less than 3.0. Ko as sets forth previously discloses 10.45 parts by weight of bisphenol-A based epoxy resin (A1) and 25 parts by weight of bisphenol-F-based epoxy resin (A2). Thus, the mass ratio (A1)/(A2) in the epoxy adhesive of Ko is 10.45/25 or 0.42, which is within the claimed range of less than 2.7. Similarly, as set forth previously in the current OA, the mass ratio (A1)/(A3) disclosed by Ko is 0.52, which is within the claimed range of (A1)/(A3) of less than 3.0. As such, applicant’s argument is not found persuasive.
With respect to (B) above, the examiner respectfully submits that the Declaration is not a proper way to overcome the rejection, because at present, claimed mass ratio (A1)/(A3) of less than 3.0 is anticipated by Ko under 35 USC 102(a)(1). Therefore, while the examiner appreciates applicant’s submission of the Declaration, the Declaration is not found persuasive.
With respect to the rejections of claims 4, 5, 8, 9, and 14-15, applicant has incorporated same arguments that are previously set forth. In response, the examiner respectfully incorporates his rebuttal as set forth previously here by reference.
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 ANISH P DESAI whose telephone number is (571)272-6467. The examiner can normally be reached Mon-Fri 8:00 am ET to 4:30 PM ET.
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, Alicia Chevalier can be reached at 571-272-1490. 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.
/ANISH P DESAI/ Primary Examiner, Art Unit 1788
May 11, 2026
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