DETAILED ACTION
This office action follows a reply filed on February 23, 2026. No claims have been amended. Claims 1-6 and 8-9 are currently pending and under examination.
The texts of those sections of Title 35 U.S. Code are not included in this section and can be found in a prior Office action.
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 103
Claims 1-6 and 8-9 are rejected under 35 U.S.C. 103 as being unpatentable over FR 2608616 in view of CN 108117739, and further in view of Zeng (US 2014/0044918).
FR ‘616 teaches a polyphenylene oxide resin composition comprising an inorganic filler, which can be used to form a printed circuit wiring substrate, the composition comprising 10-95 parts, preferably 420-80 parts of polyphenylene oxide; 1-90 parts of at least one crosslinking polymer, such as styrene butadiene copolymer, a crosslinking monomer, such as triallyl isocyanurate, or mixture thereof, which meets applicants’ (B) curing agent; and from 1-200 parts, preferably 40-100 parts by weight of an inorganic filler of a high relative dielectric constant to be more than 10 (p. 5, l. 205). FR ‘616 teaches the mineral filler to include silicon dioxide, where titanium dioxide is listed as an alternative, as well as barium titanate, strontium titanate, calcium titanate, etc. (p. 3, l. 120 to p. 4). The teaching of FR ‘616 suggests the total amount of filler as preferably 50-500 phr.
CN ‘739 teaches a PPO composite material comprising 20-29 parts PPO and 60-70 parts filler, where the filler is a mixture of strontium titanate and silica in a ratio of 5-8:1 (or about 83:17 to 89:11), teaching that within this ratio, the dielectric properties are optimal. This suggests the strontium titanate in an amount of about 172-311 phr, which overlaps with the claimed range of 25-300 phr.
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was filed to have used a combination of silica and strontium titanate as the inorganic filler in FR ‘616, as CN ‘739 teaches that such a combination allows for an optimal dielectric properties, which is similarly desired by FR ‘616 (p. 12, l. 486 and Tables).
FR ‘616 does not teach the structure of the PPO, as claimed.
Zeng teaches that polyphenylene ether resins have good dielectric properties and heat resistance, making them suitable for use in printed circuit substrates; however, because of their high melting point and poor flowability, their applications are limited, particularly in multilayer printed circuit boards (p. 1, [0004]). Zeng teaches that by reducing the molecular weight, flowability can be improved, but heat resistance is impaired (Id.). Zeng goes onto to teach that by using a vinylphenyl functionalized polyphenylene ether resin, a prepreg and laminate having excellent dielectric properties and high glass transition temperature can be prepared; however, because this composition uses isocyanuric acid triallyl (TAIC) as the crosslinking agent, it is not good for stably manufacturing prepregs and laminates due to its low molecular weight and is easily volatilized.
Zeng teaches that by using a functionalized polyphenylene ether having unsaturated double bonds at the molecule terminal and an olefin crosslinking agent, such as styrene-butadiene, a composition having excellent dielectric properties, good heat resistance and moisture resistance which is fit for multilayered printed circuit boards can be provided (p. 11, [0092]).
Zeng teaches the polyphenylene ether resin as being functionalized with one of the following terminal groups (p. 3, [0031]):
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Zeng teaches the crosslinking agent to include styrene butadiene copolymers (p. 6, [0048]-[0049]) and the filler to include silica and barium titanate (p. 7, [0053]).
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was filed to have used the functionalized polyphenylene ether of Zeng in place of the polyphenylene ether and TAIC of FR ‘616, as Zeng teaches that the elimination of the TAIC reduces volatility, improves peel strength, while providing a composition having excellent dielectric properties, which is similarly desired by FR ‘616.
FR ‘616 in view of CN ‘739, and further in view of Zeng is prima facie obvious over instant claim 1.
As to claims 2 and 3, FR ‘616 teaches the inorganic filler having a dielectric constant greater than 10 to include strontium titanate (K=300) and calcium titanate (K>10,000) (p. 4, l. 132).
As to claim 4, FR ‘616 teaches the curing agent to include modified polybutadiene, allyl compounds, acrylate compounds, etc. (p. 3, l. 101).
As to claim 5, FR ‘616 teaches a combination of titanates can be used, where a combination of strontium titanate and calcium titanate is prima facie obvious, and would be useful to adjust the dielectric constant, as mentioned below for claim 8.
As to claim 6, FR ‘616 teaches treating the inorganic filler with a silane or titanium coupling agent (p. 5, l. 196).
As to claim 8, FR ‘616 teaches that the unfilled composition has a dielectric constant of 2.6 and a dissipation fact of 0.002, whereas that comprising 255 parts barium titanate has a dielectric constant of 9.2 and a dissipation factor of 0.009 (p. 5, l. 216 to p. 6). FR ‘616 teaches that in consideration of the relative dielectric constant of 2000 of barium titanate itself, the relative dielectric constant of the composition obtained can be adjusted in practice by means of the composition ratio of barium titanate, that is, of the inorganic filler, teaching that in other words, the composition ratio of the inorganic filler with respect to the PPO resin composition should be selected for obtained a desired relative dielectric constant (Id.). Strontium titanate has a dielectric constant of about 300, suggesting that the dielectric constant can be adjusted between 2.6 to less than 9.2.
Therefore, choosing a dielectric constant between 2.6 to less than 9.2 is prima facie obvious, and overlaps with the claimed range of 3.5-7, and it has been held that overlapping ranges are sufficient to establish prima facie obviousness. See MPEP 2144.05.
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was made to have selected from the overlapping portion of the range taught by the reference because overlapping ranges have been held to establish prima facie obviousness.
As to claim 9, FR ‘616 teaches that the composition is suitable for use as a substrate for printed wiring. While FR ‘616 does not teach the use of the composition specifically as an insulating layer between 10 or more wiring layers, this is an intended use.
During examination, statements reciting the purpose or intended use of the claimed invention must be evaluated to determine whether the recited purpose or intended use results in a structural difference between the claimed invention and the prior art. See MPEP 2111.02 (II).
The claimed intended use does not result in a structural difference between the composition of the claimed invention and that of the prior art; therefore, one of ordinary skill in the art would expect the composition of FR ‘616 in view of CN ‘739 and further in view of Zheng to be suitable for use as an insulating layer between 10 or more wiring layers, as claimed.
Claims 1-4, 6 and 8-9 are rejected under 35 U.S.C. 103 as being unpatentable over Zeng (US 2014/0044918) in view of CN 108117739, as evidenced by CN 119350763. For convenience, the machine translations of CN ‘739 and CN ‘763 will be cited below.
Zeng teaches a polyphenylene ether resin composition comprising (A) a functionalized polyphenylene ether resin, which has unsaturated double bonds of one of the following at the molecular terminal:
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(B) crosslinking agent, which includes styrene-butadiene copolymer (p. 6, [0048]-[0049]); (C) initiator; and 5-300 parts by weight of a filler, based on 100 parts of (A) and (B), where the filler is taught to include silica and strontium titanate (p. 7, [0053]), where (A) is present in an amount of 20-90 wt% of the total amount of (A) and (B) (p. 6, [0047]).
Zeng teaches the claimed composition but does not specifically teach a combination of strontium titanate and silica, as claimed.
CN ‘739 teaches a PPO composite material comprising 20-29 parts PPO and 60-70 parts filler, where the filler is a mixture of strontium titanate and silica in a ratio of 5-8:1 (or about 83:17 to 89:11), teaching that within this ratio, the dielectric properties are optimal. This suggests the strontium titanate in an amount of about 172-311 phr, which overlaps with the claimed range of 25-300 phr.
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was filed to have used a combination of silica and strontium titanate as the inorganic filler in Zeng, as CN ‘739 teaches that such a combination allows for an optimal dielectric properties, which is similarly desired by Zeng.
Note CN ‘739 teaches the PPO as having a low viscosity, specifically about 0.36-0.4 dl/g, where SA9000, as evidenced by Zeng, has a viscosity of about 0.3 dl/g, as evidenced by CN ‘763 ([0045]).
The amount of (A) overlaps with the claimed amount of 30-65 parts, and it has been held that overlapping ranges are sufficient to establish prima facie obviousness. See MPEP 2144.05.
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was made to have selected from the overlapping portion of the range taught by the reference because overlapping ranges have been held to establish prima facie obviousness.
Zeng in view of CN ‘739 is prima facie obvious over instant claims 1 and 4.
As to claim 2, Zeng teaches the inorganic filler to include strontium titanate (K=300).
As to claim 3, Zeng teaches the filler to include barium titanate, as well. Choosing a combination of strontium titanate and barium titanate is prima facie obvious.
As to claim 6, Zeng teaches treating the inorganic filler with a silane or titanium coupling agent (p. 7, [0054]).
As to claim 8, Zeng teaches a dielectric constant of 3.5 and a dielectric dissipation factor of about 0.004 (p. 10, Table 1).
As to claim 9, Zeng teaches that the composition is suitable for preparing a multi-layer printed circuit board (p. 11, [0092]). While Zeng does not teach the use of the composition specifically as an insulating layer between 10 or more wiring layers, this is an intended use.
During examination, statements reciting the purpose or intended use of the claimed invention must be evaluated to determine whether the recited purpose or intended use results in a structural difference between the claimed invention and the prior art. See MPEP 2111.02 (II).
The claimed intended use does not result in a structural difference between the composition of the claimed invention and that of the prior art; therefore, one of ordinary skill in the art would expect the composition of Zheng in view of CN ‘739 to be suitable for use as an insulating layer between 10 or more wiring layers, as claimed.
Response to Arguments
Applicant's arguments filed February 23, 2026 have been fully considered but they are not persuasive.
Applicants argue that FR ‘616 desires a high molecular weight PPO with an OH terminal group, whereas Zeng teaches a low molecular weight PPO with an unsaturated terminal group.
The examiner agrees; however, Zeng provides motivation for using a lower molecular weight PPO and that with an unsaturated terminal group, specifically teaching that reducing the molecular weight can decrease the processing temperature and increase the flowability of the PPO, but heat resistance is also impaired, teaching that by functionalizing the terminals with unsaturated groups improves the heat resistance, and also requires proper selection of a crosslinking agent, to provide good dielectric properties and heat resistance, all while providing a PPO with good processability. See p. 1 of Zeng.
Applicants argue that it would not have been obvious to replace the PPO of FR ‘616 with that of Zeng due to the difference in molecular weight and functional group, arguing that this significantly changes the curing mechanism; however, Zeng provides motivation for reducing the molecular weight, and functionalizing the PPO, teaching the proper selection or a curing agent, which includes that taught by FR ‘616.
Applicants argue an epoxy resin or the like is required to crosslink the PPO of FR ‘616; however, the examiner disagrees, as styrene-butadiene is used as the crosslinking agent.
Applicants argue that the resin in CN ‘739 is a thermoplastic, not a thermosetting resin. Zeng exemplifies the use of SA9000, which as evidenced by Cheon is a thermoplastic (US 2015/0002364, p. 23, [0196]). Additionally, regardless of whether the PPO is thermoplastic or thermosetting, one of ordinary skill in the art would expect the combination of strontium titanate and silica to provide similar improvements in dielectric properties.
The examiner also included a rejection over Zeng in view of CN ‘739, for consideration due to the arguments regarding the differences in FR ‘616 and Zeng. Claim 1 can be rejected over Zeng and CN ‘739 without the need for FR ‘616, as proposed, above.
Conclusion
THIS ACTION IS MADE FINAL. 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 BRIEANN R JOHNSTON whose telephone number is (571)270-7344. The examiner can normally be reached Monday-Friday, 8:00 AM - 4:00 PM EST.
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/Brieann R Johnston/Primary Examiner, Art Unit 1766
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