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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 March 18, 2026 has been entered.
Claims 1, 4, and 6-10 are pending as amended on March 18, 2026. Support for amended claims 1, 4, and 6 is found in original claims 1-6. Claims 3 and 5 are canceled.
Any objections and/or rejections made in the previous Office action and not repeated below are hereby withdrawn.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 March 18, 2026 have been fully considered.
Applicant’s arguments, see page 19, with respect to the rejection under 35 U.S.C. 103 over Huang (WO 2020150918 A1, US 2021/0364919 A1 is used as an English translation) in view of Lu (US 2007/0166535 A1) have been fully considered and are persuasive. To arrive at the polyimide of amended claim 1 using the disclosure of Huang, one would have to select as the dianhydride component a combination of two dianhydrides where the two dianhydrides are BPADA from the list in [0035] and a dianhydride corresponding to C is
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where R4 is an aryl in [0037]. One would further need to select as the diamine a combination of two diamines where the two diamines are APB-N and HFBAPP from the list in [0036]. Huang does not teach the claimed 6:4 to 8:2 first dianhydride to second dianhydride ratio. Lu teaches a range of 1:9 to 9:1 (Lu, [0023] and [0026]), but does not provide sufficient motivation to for one of ordinary skill to modify Huang with Lu’s range of 1:9 to 9:1 and further select the overlapping portion of the range without impermissible hindsight. The rejections over Huang in view of Lu have been withdrawn.
However, new grounds of rejection have been made of amended claims 1, 4, 6-7, and 10 over Lu (US 2007/0166535 A1), as laid out below.
Applicant argues (page 18) that the claimed molar ratio of first dianhydride to second dianhydride of 6:4 to 8:2 would not have been obvious given Lu’s range of 1:9 to 9:1. MPEP 2144.05.I. states that where claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists. Applicant can rebut a prima facie case of obviousness by showing the criticality of the range. See MPEP § 2144.05.III.A. Applicant’s argument of unexpected results is addressed below. Because unexpected results have not been established for claim 1 (see argument below), the overlap of Lu’s range of 1:9 to 9:1 with the claimed range of 6:4 to 8:2 is sufficient to establish a prima facia case of obviousness.
Applicant argues (page 19-23) that polyimides with a specific ratio of first dianhydride to second dianhydride within the claimed range of 6:4 to 8:2 unexpectedly exhibit improved properties, including film formation capability, low dielectric constant at 10 GHz, low dielectric loss factor and 10 GHz, and low water absorption rate. Applicant points to Examples 1-2, 7-8, and 10-14 as well as Comparative Examples 1-6. Evidence of nonobviousness must be commensurate in scope with the claims which the evidence is offered to support. See MPEP 716.02(d). Applicant has amended claim 1 such that the claimed combinations of monomers are consistent with those used in Examples 1-14. However, Applicant has not yet established unexpected results that are commensurate in scope with the claimed invention because claim 1 has not been amended to be commensurate in scope with the examples for which unexpected results has been demonstrated. In the 7/17/2025 Office action (see the paragraph starting at the end of page 4), the Examiner suggested that the data would be persuasive for demonstrating that a film composition comprising a solvent and a polyimide derived from a 60:40 to 70:30 mixture of BPADA and TAHQ as the dianhydride component and a 40:60-70:30 mixture of ODA and HFBAPP as the diamine component has the unexpected result of forming a film (Examples 5-6 and 8). The Examiner also suggest that the data would be persuasive for showing that a film composition comprising a solvent and a polyimide derived from a 70:30 to 80:20 mixture of BPADA and TAHQ as the dianhydride component and a 40:60 mixture of APB-N and HFBAPP as the diamine component has the unexpected result of forming a film (Examples 10-12). Applicant has not amended the claims to be commensurate in scope with these examples at least because claim 1 does not require a solvent and encompasses a broader range of monomer combinations and ratios than Examples 5-6, 8, and 10-12.
Applicant argues (page 23) that the data show a consistent and predictable trend throughout the claimed dianhydride molar ratio range that is not confined to a single diamine ratio or isolated combination but instead arise from the claimed structural design principle. Applicant goes on to state that one would reasonably infer that the demonstrated structural-property relationship applies across the scope of claim 1. MPEP 716.01(c) II states that arguments presented by the applicant cannot take the place of evidence in the record. In re Schulze, 346 F.2d 600, 602, 145 USPQ 716, 718 (CCPA 1965). Applicant’s argument is not persuasive because claim 1 does not limit the diamine monomer ratios, but no evidence has been provided of a structural-property relationship applying over broad ratios of the claimed diamines. For example, Example 8 and Comparative Example 3 are derived from BPADA, TAHQ and a 4:6 combination of ODA and HFBAPP. From these examples, there is no way to determine if film formation would occur or be expected for any other ratio of ODA and HFBAPP because only one ODA:HFBAPP ratio has been considered. As another example, Examples 10-12 and Comparative Example 4 use a 4:6 ratio of APB-N to HFBAPP, but provide no evidence of unexpected properties at other ratios of APB-N and HFBAPP.
Applicant disagrees (page 22-23) that the presence of a solvent is necessary for claim 1 to be commensurate in scope with the instant examples. Applicant argues that while the examples use film formation as a practical application and testing platform, the focus of the present invention resides in the chemical structure of the polyimide itself and that measured properties reflect the intrinsic chemical structure of the claimed polyimide, not the presence of solvent. Applicant argues that film formation is an unexpected benefit of the claimed polyimide composition, but Applicant has only demonstrated film formation in the presence of a solvent. For example, Examples 10-12 and Comparative Example 4 use 25 wt% solids compositions in NMP. Applicant has provided not provided sufficient evidence that the presence, amount, or type of solvent does not impact the ability to form a film. In addition, the ability to produce a polyimide film comprising a polyimide reading on claim 1 is not unexpected given the teachings of Lu because Lu teaches films comprising polyimides that read on claim 1 (see the claim 10 discussion below). What Lu does not suggest is a composition comprising a fully imidized polyimide and a solvent that can then be used to form a film.
Claim Rejections - 35 USC § 103
Claims 1, 4, 6-7, and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Lu (US 2007/0166535 A1, cited with 3/26/2025 Office action).
Regarding claim 1, Lu teaches a polyimide which is a reaction product of a reactant (a) and a reactant (b) (Lu, [0026]).
Lu teaches polyimide copolymers featuring repeat units of formulae I and II shown below (Lu, [0023])
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Where X represents a quadrivalent aromatic group (Lu, [0025]) and Ar1 and Ar2 represent bivalent aromatic groups (Lu, [0024]).
In formula I, the dianhydride component is 1,3-dihydro-1,3-dioxo-5-isobenzofurancarboxylic acid phenylene ester (TAHQ) (Lu, [0027]) while the dianhydride component in formula 2, corresponding to X, can be 2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (BPADA) (last structure in Lu, [0025]). A combination of BPADA and TAHQ reads on the reactant (a) consists of a first dianhydride and a second dianhydride, wherein the first dianhydride (BPADA) is
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and the second dianhydride (TAHQ) is
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.
Lu teaches that Ar1 and Ar2 in formulae I and II are bivalent aromatic groups (Lu, [0024]). Lu [0024] further lists the preferred structures from which Ar1 and Ar2 are independently selected. These structures include
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and
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. It would have been obvious to one of ordinary skill in the art prior to the effective filing date to have selected any combination of Ar1 and Ar2 taught by Lu, including a combination of
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and
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, because Lu teaches these residues for Ar1 and Ar2. A polyimide where Ar1 and Ar2 are a combination of
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and
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reads on wherein the reactant (b) is a combination of
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and
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.
Lu does not anticipate wherein the molar ratio of the first dianhydride to the second dianhydride is 6:4 to 8:2.
However, Lu teaches that the mole fraction of the repeating unit of formula I is about 10-90%, and that of formula II is about 90-10% (Lu, [0026]). Formula 1 is derived from TAHQ and Formula 2 is derived from BPADA, so the mole fraction of formulae I to II corresponds to a 1:9 to 9:1 range of the first dianhydride (BPADA) to the second dianhydride (TAHQ). 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 used any molar ratio of first dianhydride to second dianhydride in the range of 1:9 to 9:1 because Lu teaches this range. A range of 1:9 to 9:1 overlaps with the claimed range of 6:4 to 8:2. 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.
Regarding claims 4 and 6, Lu teaches the polyimide of claim 1 where reactant (b) is a combination of
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and
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. This polyimide satisfies claims 4 and 6 because these claims further limit alternative combinations of diamines (reactant (b)) that are recited in claim 1, but not required by claims 1, 4, or 6.
Regarding claim 7, Lu teaches the polyimide as claimed in claim 1. Lu further teaches that the polyimide has a weight average molecular weight between 10,000 and 80,000 (Lu, [0031]), falling within the claimed range of 5,000 g/mol and 3,000,000 g/mol.
Regarding claim 10, Lu teaches the polyimide as claimed in claim 1. Lu further teaches applying the polyimide of the invention to the surface of a single-sided copper clad laminate comprising a copper foil and a low CTE polyimide base film. Lu then carries out a heat treatment to effect imidization. The resulting laminate comprises a thermoplastic polyimide layer having a thickness of 3-5 µm (Lu, [0032]).
Claim 10 recites a film, which is a cured product of the film composition as claimed in claim 8. Claim 8 is drawn to a composition comprising the polyimide of claim 1 and a solvent. Curing the polyimide would remove the solvent, leaving behind a polyimide film. Lu’s layer of polyimide of claim 1 has undergone a heat treatment to effect imidization and would similarly remove any solvent. Lu’s polyimide layer therefore reads on the film of claim 10. It is noted that while claim 10 claims a film that is a cured product of the film composition as claimed in claim 8, case law holds that:
Even 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. See In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985).
To the extent that the process limitations in a product-by-process claim do not carry weight absent a showing of criticality, the reference discloses the claimed product in the sense that the prior art product structure is seen to be no different from that indicated by the claims. The prior art teaches the same product as the instant claims, regardless of the process by which the prior art product has been produced. The burden is shifted to Applicant to provide factually supported evidence which demonstrates the contrary.
Double Patenting
Claims 1, 4, and 6-10 are rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 3-4, and 7-9 of U.S. Patent No. 12,607,932 B2 (reference patent). Although the claims at issue are not identical, they are not patentably distinct from each other because the instant claims are obvious over the reference claims.
Regarding claim 1, reference claim 1 teaches a composition comprising a polyimide (col. 26, lines 33-34). The polyimide of reference claim 1 is a polyimide which is a reaction product of a reactant (a) and a reactant (b), wherein the reactant (a) consists of a first dianhydride and a second dianhydride, wherein the molar ration of the first dianhydride to the second dianhydride is 6:4 to 8:2 (col. 26, lines 37-41). Reference claim 1 teaches that the first dianhydride is
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and the second dianhydride is
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(col. 26, lines 45-60). Reference claim 1 teaches that the reactant (b) is a combination of
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,
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, and
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(col. 26, line 66- col. 27, line 25).
Regarding claim 4, reference claim 1 teaches the polyimide of claim 1. This polyimide meets the limitations of claim 4 because claim 4 further limits alternative combinations of diamines (reactant (b)) that are not required by claims 1 or 4.
Regarding claim 6, reference claim 3 further teaches that the molar ratio of
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to
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and
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is 1:99 to 1:9.
Regarding claim 7, reference claim 4 teaches wherein the polyimide has a weight average molecular weight of 5,000 g/mol to 3,000,000 g/mol.
Regarding claim 8, reference claim 7 teaches a composition comprising the polyimide as claimed in claim 1 and a solvent, wherein the film composition has a solid content of 20 wt% to 40 wt%. While reference claim 7 does not anticipate the claimed solid content, it would be obvious to one of ordinary skill to select any solid content in the range of 20-40 wt% because reference claim 1 teaches this range. A range of 20-40 wt% overlaps with the claimed range of 5-30 wt%. Selection of overlapping portion of ranges has been held to be a prima facie case of obviousness. See MPEP § 2144.05.I.
Regarding claim 9, reference claim 8 further teaches wherein the solvent is N-methylpyrrolidinone, dimethylacetamide, or γ-butyrolactone (col. 28, lines 29-31).
Regarding claim 10, reference claim 9 further teaches a film which is a cured product of the film composition as claimed in claim 8.
Allowable Subject Matter
Claims 8-9 are rejected on the ground of nonstatutory double patenting, but would be allowable should the nonstatutory double patenting rejections be overcome.
The following is a statement of reasons for the indication of allowable subject matter:
As of the date of this office action, no prior art references, whether considered individually or in combination have been identified to anticipate or render obvious the claimed invention under 35 U.S.C. §102 or §103.
The closest prior art of record is Lu (US 2007/0166535 A1) and Huang (WO 2020150918 A1, US 2021/0364919 A1 is used as an English translation, cited with 3/26/2025 Office action).
Lu teaches the polyimide of claim 1, as discussed above. Lu does not teach or suggest a composition comprising the polyimide of claim 1 and a solvent, wherein the film composition has a solid content of 5wt% to 30wt%, as required by claim 8. Lu performs the imidization step after coating (Lu, [0032] and [0042]), suggesting that the “polyimide” used to making the coating is a polyimide precursor that then undergoes heat imidization to form a polyimide after being coated to form a film.
Huang teaches a film composition, comprising the polyimide and a solvent (The components listed below were mixed with a solvent in a weight ratio as shown in Table 1, Huang, [0066]; components B1 and B2 are in Huang Table 1 are polyimides; the photosensitive resin composition was coated on a copper foil substrate, and then dried at 90°C for 5 min to obtain a surface-dried film, Huang, [0079])). Huang further teaches wherein the solvent is N-methylpyrrolidinone, dimethylacetamide, or γ-butyrolactone (Huang, [0048]) and wherein the film composition has a solid content of 30wt% (DMAc solution having a solid content of 30%, Huang, [0066]).
Huang does not teach the polyimide of claim 1. To arrive at the polyimide of claim 1 based on the disclosure of Huang, one would have to select as the dianhydride component a combination of two dianhydrides where the two dianhydrides are BPADA from the list in [0035] and a dianhydride corresponding to C is
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where R4 is an aryl in [0037]. One would further need to select as the diamine a combination of two diamines where the two diamines are APB-N and HFBAPP from the list in [0036]. Huang does not teach the claimed 6:4 to 8:2 first dianhydride to second dianhydride ratio. Lu teaches a range of 1:9 to 9:1 (Lu, [0023] and [0026]), but does not provide sufficient motivation to for one of ordinary skill to modify Huang with Lu’s range of 1:9 to 9:1 and further select the overlapping portion of the range without impermissible hindsight.
Claim 8 is allowable. Claim 9 depends from claim 8 and is therefore allowable.
Conclusion
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.
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/AUDRA J DESTEFANO/Examiner, Art Unit 1766
/RANDY P GULAKOWSKI/Supervisory Patent Examiner, Art Unit 1766
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