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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 3/12/2026 has been entered.
Status of Claims
The examiner acknowledges the amendments to claims 1 and 17 as well as the cancellation of claims 7, 8, 15, and 19-25. Claims 1-6, 9-14, and 16-18 are pending.
Claim Interpretation
Claim 1 requires the mixing of two different grades of bisphenol epoxies. However, as the same bisphenol resin can be present in both grades, with the grades differing in the amount of impurities, this constitutes a product-by-process claim as the properties of the resin would be determined by the mixing ratio of the two. As such, any composition in which the bisphenol epoxy resin meets the final resin grade would meet the requirements of the instant claims.
Claim Rejections - 35 USC § 112
The applicant has defined parameters for the standard resin. The prior 112(b) rejection has been withdrawn.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-6, 9, 11-14, and 16-18 are rejected under 35 U.S.C. 103 as being unpatentable over Liang (US 20170145180, Patent Application Publication 1 from IDS dated 7/8/2022) in view of Morganelli (US 20150221527).
Regarding Claim 1,
Liang teaches a composition that includes diepoxide resins that are well known in the art (Paragraph 22), which would include the use of bisphenol A and F based epoxy resins in addition to degradable curing agents that are labile under acidic conditions (Paragraph 22). These structures include acetals as in curing agent A (para. 42):
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as well as ketals such as in curing agent B (para. 44):
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as well as a variety of other structures.
Liang does not teach the usage of high purity epoxy resins. However, Morganelli teaches that high purity epoxy resins impart higher glass transition temperatures and lead to materials with fewer cracking issues while simultaneously improving stiffness and modulus of the resulting cured product (Paragraph 4) and demonstrates the use of bisphenol based epoxy resins such as high purity bisphenol F (Epiclon 830 LVP, Examples 1-3). One of ordinary skill in the art would recognize the value of improving these characteristics in a structural composite and would logically look to incorporate these findings. It would therefore have been obvious to have combined the epoxy resin composition of Liang with the use of high purity resins as taught by Morganelli to obtain a resin composition with the predictable outcome of improved stiffness and cracking resistance with a reasonable expectation of success. Furthermore, "It is prima facie obvious to combine two compositions each of which is taught by the prior art to be useful for the same purpose, in order to form a third composition to be used for the very same purpose.... [T]he idea of combining them flows logically from their having been individually taught in the prior art." In re Kerkhoven, 626 F.2d 846, 850, 205 USPQ 1069, 1072 (CCPA 1980) (citations omitted) (Claims to a process of preparing a spray-dried detergent by mixing together two conventional spray-dried detergents were held to be prima facie obvious.). See also In re Crockett, 279 F.2d 274, 126 USPQ 186 (CCPA 1960) (Claims directed to a method and material for treating cast iron using a mixture comprising calcium carbide and magnesium oxide were held unpatentable over prior art disclosures that the aforementioned components individually promote the formation of a nodular structure in cast iron.); Ex parte Quadranti, 25 USPQ2d 1071 (Bd. Pat. App. & Inter. 1992) (mixture of two known herbicides held prima facie obvious); and In re Couvaras, 70 F.4th 1374, 1378-79, 2023 USPQ2d 697 (Fed. Cir. 2023) (That the two claimed types of active agents, GABA-a agonists and ARBs, were known to be useful for the same purpose—alleviating hypertension—alone can serve as a motivation to combine). See MPEP 2144.06.I. As both standard and high purity epoxy resins have been utilized in this manner, it would have been obvious to use the combination for the same purpose.
With regard to the requirement of impurities below 5000 ppm, because Morganelli teaches that high purity resins when incorporated into compositions show reduced cracking and increased stiffness (Paragraph 4), it would logically follow that the ordinarily skilled artisan would want to use as high of purity of material as possible in order to obtain the highest performance in the final article. As such, it would have been obvious prior to the effective filing date of the instant application to have used the highest purity, and by extension, lowest impurity containing epoxy resins.
Finally, with regard to the epoxy equivalent weight (EEW) of the standard resin, Liang teaches the use of a bisphenol A epoxy resin with a EEW of 185-192, which is within the range of the instant claims.
Regarding Claim 2,
Liang in view of Morganelli teaches the use of high purity epoxy resins, including bisphenol type epoxy resins. With regard to the usage amounts of different epoxy resins, bisphenol-based epoxy resins are commonly used in the generation of composite structures. As such, materials utilized for the same purpose may be combined and substituted for one another, as required, to fit the particular use case. "It is prima facie obvious to combine two compositions each of which is taught by the prior art to be useful for the same purpose, in order to form a third composition to be used for the very same purpose.... [T]he idea of combining them flows logically from their having been individually taught in the prior art." In re Kerkhoven, 626 F.2d 846, 850, 205 USPQ 1069, 1072 (CCPA 1980). See MPEP 2144.06.I. Additionally, as both bisphenol A and F epoxy resins are useful for the same purpose, one of ordinary skill in the art, seeking to generate a composite with the necessary strength for a specific use case, would look to alter the composition to meet this requirement. As such, it would have been obvious to have used a combination of the resins in any amount.
With regard to the incorporation of standard epoxy resin with the high purity resins, due to the burden of more stringent requirements with higher purity, it logically follows that such components are of higher cost. As such, one of ordinary skill in the art would seek to minimize the usage of such higher cost inputs to only the amount required to obtain the desired characteristics in the final material and in the processing characteristics of the mixture. This would render the amount of standard epoxy resin incorporated to be a result-effective variable and as such, it would have been obvious to have set the amount of the standard resin used based upon these characteristics.
Regarding Claims 3 and 4,
Liang teaches the use of 2,2-bis(2-aminopropoxy)propane as curing agent B shown below:
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and through its use in example 4 (Paragraph 47), in which curing agent B is the only curing agent, it meets the requirement of claim 4 of 80% or more by weight of the total curing agent.
Regarding Claim 5,
Liang teaches the use diepoxide resins (Paragraph 19) and specifically uses bisphenol A-based epoxy resins (Example 3). Example 3 makes use of a bisphenol A resin with an epoxy equivalent weight of 185-192, meeting the requirements of claim 7. However, Liang does not teach the use of high purity Bisphenol A epoxy resins. In fact, Liang is silent on the purity of the epoxy resins used. However, as the commercially available bisphenol A epoxy resins would be intended to form polymerized products, it would logically follow that such resins at any purity would be useful in the formation of a composite material, with the ordinarily skilled artisan selecting a purity that meets the material requirements of the composition mixture and/or the final composition. As such, it would have been obvious to have used any purity of bisphenol A epoxy resin with a reasonable expectation of success in forming an epoxy composite. Additionally, the listed ranges for the standard and high purity versions of the epoxy resin are adjacent to one another, differing only by 1 g/equivalent. "The proportions are so close that prima facie one skilled in the art would have expected them to have the same properties." Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985).
Regarding Claim 6,
Liang teaches the use of diepoxide resins as discussed in regard to claims 5 and 7 above, but does not teach specifically the use of bisphenol F epoxy resins nor the epoxy equivalent weight. It should be noted however that bisphenol F-based epoxy resins are diepoxides, and as such, would be allowed for use by Liang. Additionally, Morganelli teaches the use of bisphenol F epoxy resins in high purity form, specifically Epiclon 830 LVP, which meets the epoxy equivalent weight requirement of claim 6. And as discussed in regard to claims 5 and 7 above, with a variety of commercially available purities of resin meant for use in forming epoxy composition, it would have been obvious to have used the resin in any purity to form an epoxy composition with a reasonable expectation of success.
Regarding Claim 9,
Liang in view of Morganelli teaches the use of high purity epoxy resins for the purposes of generating cured composite materials, however the combination does not teach that the level of impurities be less than 6000 ppm. As previously described in regard to claim 1, Morganelli teaches that high purity epoxy resins improve the stiffness and modulus of the resulting composite as well as to improve resistance to cracking. However, as the cost of higher purity inputs would logically increase, one of ordinary skill in the art would be motivated to find a purity level that would satisfy the material requirements while seeking to limit the increase in cost required to obtain the material. As such, the purity of the resin would be a result-effective variable and it would have been obvious to have set the purity level in the range specified based upon the reasoning laid out above.
Regarding Claim 11,
Liang teaches the use of 20 grams of curing agent with 112 grams of epoxy resin (Example 3) and 20 grams of curing agent to 93 grams of epoxy resin (Example 4) which meet the requirements of the instant claim of being between 100:10 and 100:50 epoxy resin:curing agent.
Regarding Claim 12,
Liang teaches that common additives such as diluents, fillers, and viscosity modifiers may be used in the composition (Paragraph 22).
Regarding Claims 13 and 14,
Liang teaches the general use of compound classes, but does not specifically teach the reactive diluents of the instant claims. However, Morganelli teaches that hexanedioldiglycidyl ether and trimethylolpropanetriglycidyl ether specifically may be used (Paragraph 17), with the reasons for combining the teachings discussed above in regard to claim 1. Regarding the purity of the diluents, both Liang and Morganelli are silent on the purity levels used. However, because the use of such compounds is disclosed, in the absence of unexpected results, it would have been obvious to have used the reactive diluents in any purity.
Regarding Claim 16,
Liang in view of Morganelli teaches a composition containing the components as required by claim 1 and while Liang in view of Morganelli is silent on the initial mix viscosity, because the composition taught contains the same components in similar amounts, it would logically follow that the composition would have an initial mix viscosity meeting the requirements of the instant claim. "Products of identical chemical composition can not have mutually exclusive properties." In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). See MPEP 2112.01.II.
Regarding Claims 17 and 18,
Liang in view of Morganelli is silent on the pot life of the mixture. However, the pot life of the composition would be determined by the components and proportions of them used in creating the mixture. As such, it would necessarily follow that any composition meeting the requirements of the instant claim would have a reaction rate matching that of the material of the instant claim and thus, the same pot life. For this reason, it would have been obvious for the material to have the required pot life.
Similarly, the time by which strength of the composite reaches steady state would be determined by the reaction rate, and it would necessarily follow that a composition meeting the requirements of the instant claim would have a reaction rate similar to that of the composition of the instant claim and would thus achieve its final strength in a similar time frame.
Regarding the glass transition temperature, Morganelli discloses (Examples 1-3, Table 1) a variety of bisphenol-based epoxy compositions in which the glass transition temperature is above 125 °C, thus meeting the requirement of greater than 75 °C.
Claim(s) 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Liang (US 20170145180, Patent Application Publication 1 from IDS dated 7/8/2022) in view of Morganelli (US 20150221527) as applied to claims 1-6, 9, 11-14, and 16-18 above, as further evidenced by Tulchinsky (US 10,023,685).
Regarding Claim 10,
Liang and Morganelli are silent on the bisphenol epoxy resin monomer content. However, bisphenol A epoxy resins are commercially available at purity levels as disclosed in the instant claim as evidenced by Tulchinsky, who uses D.E.R. 332, a bisphenol A based epoxy resin with an epoxy equivalent weight of 171-175 g/equivalent, which would correspond to a purity in the range of the instant claim (Column 12, Lines 62-64). One or ordinary skill in the art, seeking to reduce processing steps in generation of the composition, would seek a commercial source of high purity material, if possible. As this material was available prior to the effective filing date of the instant application, it would have been obvious to used high purity bisphenol A resin.
Response to Arguments
Applicant's arguments filed 3/12/2026 have been fully considered but they are not persuasive for at least the following reasons.
On page 9, the applicant states that claim 1 is now allowable through the incorporation of limitations from claims 7, 8, and 15. However these claims were previously rejected and remain so and, as a result, their inclusion into claim 1 does not place the claim in condition for allowance simply on this basis.
On page 9, the applicant asserts that one of ordinary skill in the art would not combine the teachings to reach a slow-reacting epoxy resin. The examiner disagrees. As stated in prior rejections and responses, the applicant’s invention as described in claim 1 is a result of mixing two different grades of the same resin, one of higher purity and one of lower purity. This is functionally no different than having started with a resin of intermediate purity. As bisphenol epoxy resins, including high purity ones, exist in the prior art, this does not represent a new composition. Similarly, mixtures of bisphenol A and bisphenol F epoxies also are present in the prior art and the combination of elements known to serve the same purpose has been held to be prima facie obvious (MPEP 2144.06.I). Furthermore, the improvements to material properties of using higher purity resins are also known in the art, as noted in the rejection. Finally, Miyazawa (JP H0665476, art not cited) discloses that the use of higher purity bisphenol A increases the pot life of the composition (Paragraph 3). As such, the applicant’s results cannot be considered to be unexpected, as the pot life demonstrated is between that of the high purity resins and lower purity resins, as would be expected by the ordinarily skilled artisan.
On page 11, the applicant states that Liang does not contemplate the usage of high purity resins to be used in a recyclable composition. The examiner however points out that Liang does not place limitations on the grade of epoxy resin used and further, the composition after curing would contain the same components regardless of grade of epoxy resin that was used prior to curing. One of ordinary skill in the art would not expect the recyclability of the cured composition to change based upon the level of impurities of the starting resin since the degradable portion comes from the crosslinking agent, and as such, the ordinarily skilled artisan would expect that the use of any grade of epoxy resin would give the same results as there would be no difference in the polymer formed in the reaction.
On page 12, the applicant argues that Liang does not speak to the pot life of the composition due to the use of two different purities of resin. The examiner does not find this argument to be persuasive, as this mixture constitutes nothing more than an intermediate purity resin, which would be expected by the ordinarily skilled artisan to perform between the high and low purity versions for the reasons previously stated.
On pages 13 and 14, the applicant argues that the references do not speak to specific properties of the composition prior to curing. The examiner points to MPEP 2112.01.II, which places the burden on the applicant to prove that the use of a suitable single grade of resin that meets the requirements would not necessarily have these properties.
In summary, the applicant argues that mixing two different grades of the same compound constitutes a novel invention based upon the properties observed. The examiner reiterates the prior rejection that simply using an intermediate grade of chemical in a known composition does not represent a patentably distinct invention, especially in light of the knowledge of the prior art regarding the improvement to the applicant’s specified properties that are already known to be linked to purity. Therefore, the rejection is maintained.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Miyazawa (JPH 0665476) teaches improvements to pot life and reduced viscosity associated with the use of high purity bisphenol A and F epoxy resins. Fourie (US 3,093,661) and Cofer (US 3,413,320) teach advantages of the use of high purity epoxy resins for material properties.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ADAM J BERRO whose telephone number is (703)756-1283. The examiner can normally be reached M-F 8:30-5.
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, Heidi Kelley can be reached at 571-270-1831. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/A.J.B./Examiner, Art Unit 1765
/JOHN M COONEY/Primary Examiner, Art Unit 1765
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