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 .
Rejections Withdrawn
The 35 USC 103 rejection of claims 5 and 6 over JP ‘152 in view of JP ‘119 is expressly withdrawn. Comparative Example No. 6 in the instant specification (p. 14) contains no K, as per JP ‘152. Said Comparative Example No. 6 has a lowest magnetic loss of 276 kW/m3 when measured with a highest magnetic flux density of 50 mT and at a frequency of 500 kHz. The 276 kW/m3 is well above the upper limit of 200 kW/m3 in instant claims 5 and 6. Furthermore, JP ‘119 does not solve JP ‘152’s deficiency with respect to said lowest magnetic flux loss.
The 35 USC 103 rejection of claims 1-6 over Yoshida is withdrawn in view of Applicant’s amendment of claim 1 to require the upper mass limit of K to be 18 ppm. Yoshida’s sample No. 4-3 is the closest in Yoshida, but lacks CoO and has a K content of 20 ppm. In fact, 20 ppm is the lowest exemplified K amount in Yoshida. Yoshida’s only samples that contain CoO, i.e., sample Nos. 2-5, 2-7 and 2-8, do not contain any K (see Table 2 and Example 2). Arrival at a MnZnCo-based ferrite having the claimed amounts of CoO and K would not have been obvious, particularly in view of the experimental results obtained on pp. 13-14 of the instant specification.
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.
Claims 1-4 are rejected under 35 U.S.C. 103 as being unpatentable over JP 2017-145152 A (hereinafter “JP ‘152”) in view of JP 2000-286119 A (hereinafter “JP ‘119). The machine English translations of JP ‘152 and JP ‘119 accompanying the Office action mailed 04/23/2026 are hereinafter referred to below.
With respect to claim 1, JP ‘152 teaches a MnZnCo-based ferrite that exhibits a low core loss in a temperature range of 40 to 60°C (see the “Problem To Be Solved” on the third page). The MnZnCo-based ferrite comprises a basic component, a sub-component and inevitable impurities, wherein (see “Solution” on the third page and ¶ 0019):
the basic component includes:
Fe2O3 at not less than 52.50 mol % and not more than 53.50 mol%,
ZnO at 10.00 mol % or more and 12.50 mol% or less
CoO at 0.15 mol % or more and 0.50 mol% or less, and
MnO as the remainder;
the sub-components are, relative to the basic component:
SiO2 at not less than 50 mass ppm and not more than 500 mass ppm,
CaO at not less than 200 mass ppm and not more than 2000 mass ppm, and
Nb2O5 at 50 mass ppm and not more than 500 mass ppm;
and each of Sr and Ba in the unavoidable impurities are reduced to
Sr at 10 mass ppm or less and
Ba at 10 mass ppm or less.
Each of JP ‘152’s ferrites in Examples Nos. 1-21, 24 and 25 in Table 1 has concentrations of Fe2O3, ZnO, CoO, MnO, SiO2, CaO and Nb2O5 as here claimed. For example, Example No. 1 in JP ‘152’s Table 1 contains 53.96 mol% Fe2O3, 11.40 mol% ZnO, 0.40 mol% CoO, 34.84 mol% MnO, 120 ppm SiO2, 1470 ppm CaO, and 110 ppm Nb2O3.
JP ‘152’s MnZnCo-based ferrite differs from the instant MnZnCo-based ferrite in not requiring a K (potassium) content of 5-20 mass ppm. JP ‘152 is silent with respect to K content. However, K is known in the art as an accessory ingredient, as shown by JP ‘119
JP ‘119 teaches a ferrite having high saturation magnetic flux density, low loss in a wide frequency region, and small temperature dependency of loss in a wide temperature range, which is suitable for a magnetic core of a power transformer such as a switching power supply (see ¶ 0001). JP ‘119’s ferrite contains Fe2O3 at 52-56 mol%, ZnO at 6-14 mol%, NiO at 4 mol % or less, CoO at 0.01-0.6 mol %, SiO2 at 0.0050-0.0500 wt%, CaO at 0.0200-0.2000 wt%, and can contain Nb2O5 at 0.0050-0.050 wt% (see ¶ 0017).
JP ‘119 teaches K2O as an accessory ingredient (see “Overview” on pp. 3-4). K2O contributes to refinement of grains, and is particularly effective in reducing loss at high frequencies (see ¶ 0030). If the content is less than 0.0005 wt%, the effect is poor, while if it exceeds 0.0060 wt%, the loss becomes high, so the content is limited to the 0.0005-0.0060 wt % range, i.e. 5-60 ppm, preferably the range of 0.0010-0.0035 wt%, i.e., 10-35 ppm (see ¶ 0030).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have included K as K2O in JP ‘152’s MnZnCo-based ferrite at the concentration of 10-35 ppm taught by JP ‘119 since K2O is a known accessory ingredient in the art and contributes to refinement of grains, and is particularly effective in reducing loss at high frequencies, as taught by JP ‘119.
With respect to the properties in instant claims 2-4, i.e., the grain size and percentage of crystal grains in instant claims 2 and 3, and the lowest magnetic loss values in instant claim 4, such properties would have been obvious upon inclusion of K, i.e., K2O, in JP ‘152’s Example Nos. 1-21, 24 and 25 in the claimed range 5-20 mass ppm, which range is rendered obvious in view of JP ‘119’s teaching of a preferred range of 10-35 ppm. In particular, as noted above, JP ‘119 specifically teaches that K2O contributes to refinement of grains, and is particularly effective in reducing loss at high frequencies (see ¶ 0030). This is a matter of refining grains, and thus, grain size and percentage of crystal grains, and optimizing lowest magnetic loss, in JP ‘152’s MnZnCo-based ferrite by inclusion of K2O.
Response to Arguments
Applicant's arguments filed June 30, 2026 have been fully considered but they are not persuasive.
Patent Owner argues unexpected results for the claimed K content (Remarks, pp. 5-6):
Even assuming, arguendo, that a person of ordinary skill in the art would be motivated to incorporate K into JP '152 based on JP '119, the cited references completely fail to teach or suggest restricting the K content to the strict upper limit of 18 mass ppm or less. Restricting the K content to 18 mass ppm or less yields unexpectedly superior results. The primary objective of the present invention is to provide a MnZnCo-based ferrite with small magnetic losses over a wide frequency range and a wide temperature range. Table 1 of the specification demonstrates that ferrites falling within the claimed K range achieve substantially improved performance with respect to this objective. A direct comparison reveals the following:
Working Examples 1-15 (K content is 18 ppm or less) exhibit significantly superior properties, specifically in the lowest magnetic loss value, the magnetic loss at 40°C, and the magnetic loss at 120°C (measured at 200 mT and 100 kHz).
Comparative Examples 18-21 (K content exceeds 18 ppm) exhibit markedly inferior magnetic loss performance at both 40°C and 120°C.
Crucially, Comparative Example 18 has a K content of 25 ppm, which falls squarely within the 8.3 to 29 ppm K range taught by JP '119. Yet, despite falling within the Examiner's proposed prior art range, Comparative Example 18 exhibits clearly inferior magnetic loss values at 40°C and 120°C compared to Working Examples 1-15. This data unequivocally demonstrates that merely applying the K content taught by JP '119 to JP '152 does not inherently achieve the unexpected result of low magnetic loss over a wide temperature range (40°C to 120°C).
The data establish the criticality of the claimed upper limit. Compositions having K contents at or below 18 mass ppm achieve substantially lower magnetic losses, whereas compositions having K contents above 18 mass ppm exhibit materially degraded performance. Thus, the claimed upper limit is not an arbitrary selection from a broader range, but instead marks a meaningful performance boundary.
JP '119 only broadly teaches that K₂O contributes to the refinement of grains and is effective in reducing loss at high frequencies. It contains no disclosure or suggestion regarding the critical need to achieve low magnetic loss over a wide temperature range. Consequently, one of ordinary skill in the art would not have been motivated to discover, much less optimize and limit, the K content to 18 mass ppm or less to solve a problem not recognized in the cited art. Because the claimed invention exhibits unexpectedly superior results over the proposed prior art combination, the rejection should be withdrawn.
Applicant’s arguments are unpersuasive. The instant specification does not refer to the results in Table 1 as being “unexpected result[s]”. Rather, ¶ 0054 of the instant specification states:
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Nonetheless, the only rejected claim that requires a lowest magnetic loss is instant dependent claim 4, which requires a lowest magnetic loss value of 360 kW/m³ or less when measured with a highest magnetic flux density of 200 mT and at a frequency of 100 kHz. Comparative Example 16 in instant Table 1, like JP ‘152, has no K, but has a lowest magnetic loss value of 341 kW/m³, i.e., within the instantly claimed range, when measured with a highest magnetic flux density of 200 mT and at a frequency of 100 kHz. Similarly, Comparative Example 17 in instant Table 1 has a K content of 2 mass ppm (below the instant lower limit of 5 mass ppm), but has a lowest loss of 323 kW/m³, i.e., within the range of instant dependent claim 4.
As noted in MPEP 716.02(d) (emphasis added), “[w]hether the unexpected results are the result of unexpectedly improved results or a property not taught by the prior art, the ‘objective evidence of nonobviousness must be commensurate in scope with the claims which the evidence is offered to support.’ In other words, the showing of unexpected results must be reviewed to see if the results occur over the entire claimed range. In re Clemens, 622 F.2d 1029, 1036, 206 USPQ 289, 296 (CCPA 1980).” To the extent anything unexpected has been shown in Applicant’s specification, no criticality has been shown for the lower limit of 5 mass ppm of K. This is in view of the results for said Comparative Examples 16 and 17, which contain no K, or 2 mass ppm K, yet still achieve a lowest magnetic loss as per instant dependent claim 4.
Allowable Subject Matter
Claims 5 and 6 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
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.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALAN D DIAMOND whose telephone number is (571)272-1338. The examiner can normally be reached Monday through Thursday 5:30 am to 3:00 pm, and Fridays from 5:30 am to 9:30 am.
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Signed:
/ALAN D DIAMOND/Primary Examiner
Art Unit 3991
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