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 .
Response to Amendment and Status of Claims
Applicant’s amendments to the claims, filed April 20 2026, are acknowledged. Claims 1 and 8 are amended. No new matter has been added.
Claims 1, 3-10 and 12-19 are pending and currently considered in this office action.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1 and 3-7 are rejected under 35 U.S.C. 103 as being unpatentable over Kako2017 (previously cited, US 20170040094 A1) in view of Yoshidome (US 20190279801 A1).
Regarding Claim 1, Kako2017 discloses a soft magnetic particle (Abstract), comprising:
a coated particle including a soft magnetic metal particle and a coating layer coating a surface of the soft magnetic metal particle (Abstract),
wherein the coating layer contains at least one compound selected from mica (Abstract; para. [0042]-[0044]), and
the coating layer has an average thickness of 1-50nm (para. [0015]; para. [0044]).
Kako2017 discloses wherein the iron-based powder is an alloy such as silicon steel (Fe-Si), permalloy (Fe-Ni), permendur (Fe-Co), supermalloy (Fe-Mo-Ni) or an amorphous powder (para. [0019]), but fails to disclose the claimed alloy.
Yoshidome teaches wherein the Fe-Ni-Si-Co based alloy is an art equivalent to the Fe-Si alloy, the Fe-Ni alloy and an Fe-based amorphous alloy for a soft magnetic alloy core, and further teaches wherein the Fe-Si-B-Cr-C based alloy is a suitable choice for the amorphous Fe-based alloy (para. [0041]-[0042]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a Fe-based alloy such as the Fe-Ni-Si-Co based alloy or the Fe-Si-B-Cr-C based alloy for the soft magnetic core particle, as taught by Yoshidome, for the invention disclosed by Kako2017, because Yoshidome teaches the art equivalence of these alloys to the alloy disclosed by Kako2017 and because Yoshidome teaches wherein the Fe-Si-B-Cr-C based alloy is a suitable composition for the amorphous alloy which is expressly disclosed by Kako2017.
Regarding Claim 3 and Claim 5, Kako2017 discloses wherein the coated particle has the coating layer as an outermost layer (Fig. 2a; Fig. 2c).
Regarding Claim 4, Claim 6 and Claim 7, Kako2017 fails to disclose powder resistivity values under a pressurization load of 64MPa.
However, the structure disclosed by Kako2017 is the same as the claimed invention, and comprises a soft magnetic metallic core with an insulation coating which is an outermost layer, wherein the insulation coating comprises at least one of mica, and comprises a thickness of preferably 1-20nm or less, which is within the claimed range of 1-50nm (see Claims 1 and 3). Therefore, one of ordinary skill in the art would appreciate the soft magnetic metal powder of Kako2017 to comprise the claimed features when subjected to the claimed load, and therefore to comprise a powder resistivity during pressurization at 25C and 64MPa of 1x103 Ω-cm or more.
When 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 has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Claims 8-10 and 16-19 are rejected under 35 U.S.C. 103 as being unpatentable over Uozumi (previously cited, US 20130038420 A1) in view of Yoshidome (US 20190279801 A1) and Kako2017 (previously cited, US 20170040094 A1).
Regarding Claim 8, Uozumi discloses a dust core (Abstract; para. [0095]), comprising:
soft magnetic metal particles (para. [0073]), wherein
an average particle size of the soft magnetic metal particles is 1-70um, which reads on the claimed range of 1-20um (para. [0074]); and
an insulating layer coating on the surface of the soft magnetic particle, and therefore an interface layer present at an interface between the soft magnetic metal particles (para. [0075]; one of ordinary skill in the art would appreciate that for multiple consolidated particles each with a non-magnetic metal oxide coating layer which covers the surface thereof, the coating layer would be an interface layer between the soft magnetic metal particles – see also para. [0101]),
wherein a thickness of the insulating layer, and therefore the interface layer, is 10nm-1um, which reads on the claimed range of 1-20nm (para. [0078]).
Uozumi discloses wherein the soft magnetic particle is an alloy such as a ferroalloy such as an Fe-Si based alloy, an Fe-Al based alloy, an Fe-Ni based alloy, and an Fe-Al-Si alloy, for example (para. [0073]), but fails to disclose the claimed alloy.
Yoshidome teaches wherein the Fe-Ni-Si-Co based alloy or an amorphous alloy such as the Fe-Si-B-Cr-C based alloy is an art equivalent to the Fe-Si alloy, Fe-Al alloy, Fe-Ni alloy and Fe-Si-Al alloy (para. [0041]-[0042]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a Fe-based alloy such as the Fe-Ni-Si-Co based alloy or the Fe-Si-B-Cr-C based alloy for the soft magnetic core particle, as taught by Yoshidome, for the invention disclosed by Uozumi, because Yoshidome teaches the art equivalence of these alloys to the alloy disclosed by Uozumi, and therefore would be suitable as the soft magnetic particle composition.
Uozumi discloses wherein an insulating coating may be one comprising excellent insulating properties, and may be a silicon compound, aluminum compound, or a silicate compound (para. [0075]), but does not disclose comprising one of mica, as claimed.
Kako2017 teaches a soft magnetic core with an insulating coating which is 1-20nm, wherein the insulating coating is a swellable layered clay mineral such as mica-group and tetrasilicic fluorine mica, and the thickness is obtained and easily controlled by cleaving, thereby obtaining high heat resistance and insulating performance even when having a small thickness (Abstract; para. [0015]; para. [0042]-[0044]; para. [0046]-[0047]; Fig. 2c). One of ordinary skill in the art would appreciate a mica-group compound to read on a silicon compound, aluminum compound and a silicate compound, as disclosed by Uozumi (micas comprise silicon and aluminum and are known as silicates). Additionally, Uozumi also desires high heat resistance from the insulating layer (para. [0093]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used an insulating coating, and therefore interface layer, comprising mica, as taught by Kako2017, for the invention disclosed by Uozumi. One would be motivate to use mica in order to easily control the thickness of the insulating layer by cleaving and to provide an insulating coating which has high heat resistance and insulating performance even at small thicknesses (see teachings above). Additionally, one would be motivated to use mica because this material would be a suitable insulator material for the invention of Uozumi because it is an aluminum compound, silicon compound, silicate compound, and comprises insulating properties and high heat resistance, as required and also desired, respectively, by Uozumi (see teachings above).
Uozumi fails to disclose the molding density (molding density is interpreted to be the final relative density of the dust core); however, Uozumi and Kako2017 disclose the same molding material as the instant invention (see above particle size diameter and composition and layer thickness and composition; see also instant invention para. [0029], particle coating thicknesses), and Uozumi discloses the same compaction pressures (instant invention, para. [0043], wherein high density is achieved by the coating material type, or by molding above 1000MPa; Uozumi, para. [0084], compacting at 390-1500 MPa to obtain high relative density; Kako2017 also discloses the same coating material type which instant invention attributes to achieving the claimed density).
Therefore, it would be obvious that the invention of Uozumi and Kako2017 result in the claimed relative density of 85% or more because the molding material type (particle size, particle composition, layer thickness, layer composition) and molding conditions of Uozumi and Kako2017 are the same as the instant invention. When 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 has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Further, Kako2017 teaches compression molding to obtain a relative density of 94.5-97% in order to balance stability of the magnetic core with the ability to impregnate sealing material into inner pores of the magnetic core (para. [0049]-[0050]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have comprised a relative density of 94.5-97%, as taught by Kako2017, for the invention disclosed by Uozumi and Kako2017, in order to balance stability of the magnetic core with the ability to impregnate sealing material into inner pores of the magnetic core (see teaching above).
Regarding Claim 9, Kako2017 discloses a molding density of 94.5-97% (see teaching above in Claim 8; see para. [0049]-[0050]).
Additionally, Uozumi and Kako2017 disclose the same molding material as the instant invention (see above particle size diameter and composition and layer thickness and composition; see also instant invention para. [0029], particle coating thicknesses), and Uozumi discloses the same compaction pressures (instant invention, para. [0043], wherein high density is achieved by the coating material type, or by molding above 1000MPa; Uozumi, para. [0084], compacting at 390-1500 MPa to obtain high relative density; Kako2017 also discloses the same coating material type which instant invention attributes to achieving the claimed density).
Therefore, it would be obvious that the invention of Uozumi and Kako2017 result in the claimed relative density of 89.40-96.60% or more because the molding material type (particle size, particle composition, layer thickness, layer composition) and molding conditions of Uozumi and Kako2017 are the same as the instant invention. When 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 has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Regarding Claim 10 and Claim 19, Uozumi fails to disclose a volume resistivity of the dust core.
However, the structure of Uozumi and Kako2017 is the same as claimed (magnetic particle composition and particle size, interface layer composition and thickness, and a molding density – see Claim 8 above and teachings of Kako2017 regarding interface layer composition and also molding density), and one of ordinary skill in the art would have expected the dust core of Uozumi and Kako2017 to comprise the claimed range of loss at the claimed parameters because the structure of Uozumi and Kako2017 is identical to the claimed structure.
When 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 has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Further, Kako2017 discloses wherein the volume resistivity of the mica insulating layer is 1012 Ohm-cm, which reads on the claimed limitation of a volume resistivity of 20 Ohm-cm or more (para. [0016]). The claims do not currently specify that a volume resistivity is one of the dust core, or which component of the dust core comprises the claimed volume resistivity).
Regarding Claim 16, Uozumi and Kako2017 discloses wherein the soft magnetic particle and the interface layer are in direct contact with each other (para. [0039], surface of soft magnetic particle is coated with insulating layer; Kako2017, Fig. 3A-3B).
Regarding Claim 17, Uozumi fails to disclose a loss of 1000 kW/m3 when a magnetic field of 0.1T and 50kHz is applied.
However, the structure of Uozumi and Kako2017 is the same as claimed (magnetic particle composition and particle size, interface layer composition and thickness, and a molding density – see Claim 8 above and teachings of Kako2017 regarding interface layer composition and also molding density), and one of ordinary skill in the art would have expected the dust core of Uozumi and Kako2017 to comprise the claimed range of loss at the claimed parameters because the structure of Uozumi and Kako2017 is identical to the claimed structure.
When 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 has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Regarding Claim 18, Uozumi discloses wherein the magnetic core is usable for a reactor, transformer, a motor, and a choke coil (para. [0109]), but fails to disclose using the magnetic core for specifically an inductor.
Kako2017 teaches wherein soft magnetic cores usable for a reactor, transformer, motor, and choke coils, are also suitable for a power inductor (para. [0003]; para. [0062]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used the magnetic core of Uozumi for an inductor, as taught by Kako2017, because Uozumi discloses wherein the magnetic core is usable for high performance in high frequency power sources such as reactors, transformers, motors and choke coils, and Kako2017 teaches these properties are further well suited for an inductor in addition to said usages (see teaching above).
Claims 12-15 are rejected under 35 U.S.C. 103 as being unpatentable over Uozumi (previously cited, US 20130038420 A1) in view of Yoshidome (US 20190279801 A1) and Kako2017 (previously cited, US 20170040094 A1), as applied to Claim 8 above, in further view of Kako2018 (previously cited, US 20180281061 A).
Regarding Claim 12, Uozumi does not further disclose a binding material.
Kako2018 teaches a magnetic core comprising soft magnetic powder coated with an insulating layer, and a glass binding material therebetween soft magnetic power grains, wherein the glass binding material comprises V2O5-based frit, SnO-based frit, ZnO-based frit, B2O3-based frit and Bi2O3-based frit, and mixtures thereof, in order to increase the mechanical strength and radial crushing strength of the magnetic core, and to produce a magnetic core which is well-balanced between binding the soft magnetic powders to each other and the magnetic permeability (Abstract; para. [0014]; para. [0018]-[0019]; para. [0028]; para. [0037]; para. [0046]).
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 a glass binding material, such as one comprising a glass frit which is V2O5-based, SnO-based, ZnO-based, B2O3-based, Bi2O3-based, or comprising mixtures thereof, as taught by Kako2018, for the invention disclose by Uozumi, in order to increase the mechanical strength and radial crushing strength of the magnetic core, and to produce a magnetic core which is well-balanced between binding the soft magnetic powders to each other and the magnetic permeability (see teaching above).
Regarding Claim 13, Kako2018 discloses wherein the binding material is glass (para. [0037]).
Regarding Claim 14, Kako2018 discloses wherein the glass of the binding material contains at least one of bismuth, boron, vanadium, tin and zinc (para. [0037]).
Regarding Claim 15, Kako2018 discloses wherein the interface layer and the binding material are in direct contact with each other (Fig. 2b; para. [0037]; para. [0046], contacts and binds the soft magnetic powder (which contains interface layer) together, and therefore is in direct contact with the interface layer).
Claim 17 is alternatively rejected under 35 U.S.C. 103 as being unpatentable over Uozumi (previously cited, US 20130038420 A1) in view of Yoshidome (US 20190279801 A1) and Kako2017 (previously cited, US 20170040094 A1), as applied to Claim 8 above, in further view of Matsutani (previously cited, US 6063209 A).
Regarding Claim 17, Uozumi fails to disclose a loss of 1000 kW/m3 when a magnetic field of 0.1T and 50kHz is applied.
Matsutani teaches wherein the selection standard in a choke coil for countermeasure against harmonic distortion is a core loss of 1000kW/m3 or less in the condition of a magnetic field of 0.1T and a frequency of 50Hz (Col. 5, lines 28-24).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have comprised a loss of 1000kW/m3 or less when a magnetic field of 0.1T and 50Hz is applied, as taught by Matsutani, for the invention disclosed by Uozumi, in order to produce a choke coil (see para. [0109] of Uozumi, disclosing a choke coil) which is up to standard for a choke coil with countermeasure against harmonic distortion (see teaching by Matsutani above).
Claims 8-10, 12, 16-17 and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Moro (previously cited, US 5348800 A) in view of Yoshidome (US 20190279801 A1) and Watanabe (previously cited, US 20220059263 A1).
Regarding Claim 8, Moro discloses a dust core (Col. 1, lines 14-15; Col. 10, lines 34-39; magnetic core reads on dust core), comprising:
soft magnetic metal particles (Col. 5, lines 19-30), wherein
an average particle size of the soft magnetic metal particles is 5-100um, which reads on the claimed range of 1-20um (Col. 3, lines 5-6); and
an interface layer present at an interface between the soft magnetic metal particles (Col. 5, lines 55-67, wherein soft magnetic metal particles are coated with a non-magnetic oxide layer; see also Col. 2, lines 39-45; one of ordinary skill in the art would appreciate that for multiple consolidated particles each with a non-magnetic metal oxide coating layer which covers the surface thereof, the coating layer would be an interface layer between the soft magnetic metal particles),
wherein the non-magnetic oxide layer, and therefore the interface layer, is 0.02-1um (20-1000nm), which reads on the claimed range of 1-20nm (Col. 6, lines 3-6); and
a molding density is 85% or more (Col. 9, line 38, at least 95% density; Col. 12, line 35-36).
Further, in regards to the oxide coating, Moro teaches wherein too thick of coatings adversely affect the magnetic properties, and therefore one of ordinary skill in the art would be motivated to comprise a coating thickness of 20nm, which reads on the claimed range of 1-20nm, in order to maximize magnetic properties (Col. 6, lines 3-6).
Regarding the particle size and the interface layer thickness, in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). See MPEP § 2144.05.I.
Moro discloses wherein the soft magnetic particle are alloys such as Fe-Al-Si based alloy, Fe-Si based alloy, and Fe-Ni based alloy, for example (Col. 5, lines 19-27), but fails to disclose the claimed alloy.
Yoshidome teaches wherein the Fe-Ni-Si-Co based alloy or an amorphous alloy such as the Fe-Si-B-Cr-C based alloy is an art equivalent to the Fe-Si alloy, Fe-Ni alloy and Fe-Si-Al alloys (para. [0041]-[0042]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a Fe-based alloy such as the Fe-Ni-Si-Co based alloy or the Fe-Si-B-Cr-C based alloy for the soft magnetic core particle, as taught by Yoshidome, for the invention disclosed by Moro, because Yoshidome teaches the art equivalence of these alloys to the alloy disclosed by Moro, and therefore would be suitable as the soft magnetic particle composition.
Moro discloses wherein the non-magnetic oxide material comprises, by example, one of alumina (aluminum oxide), but does not expressly disclose one of molybdenum oxide (Col. 5, lines 65-66).
Watanabe teaches a 1-20nm metal oxide passivation layer, wherein the metal oxide is at least one of chromium oxide, aluminum oxide, tungsten oxide and molybdenum oxide, in order to reduce the eddy current loss (para. [0045]; para [0047]). One of ordinary skill in the art would appreciate that molybdenum oxide, like aluminum oxide, is non-magnetic, as desired by Moro (Col. 5, lines 55-60). Watanabe therefore also recognizes the art equivalence of molybdenum oxide and aluminum oxide for use as a thin non-magnetic metal oxide layer on the surface of a soft magnetic particle, with the benefit of reducing eddy current loss as taught by Watanabe.
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 molybdenum oxide for the non-magnetic metal oxide layer, as taught by Watanabe, for the invention disclosed by Moro, in order to reduce eddy current loss, and because molybdenum oxide is an art equivalent for a metal oxide surface layer on a soft magnetic particle to be used in a dust core, as demonstrated by Watanabe (see teachings above; see MPEP 2144.06.I&II).
Regarding Claim 9, Moro discloses a molding density from 89.40-96.60% (Col. 9, line 38, at least 95% density; Col. 12, line 35-36).
Regarding Claim 10 and Claim 19, Moro discloses a volume resistivity of 20 Ω-cm or more (Table 1, resistivity ρ is 105 Ω-cm for inventive examples 11, 13, 21, 23, 31, 33, 41 and 51; see also Col. 7, lines 60-63).
Regarding Claim 12, Moro discloses a binding material at a grain boundary between the soft magnetic metal particles (Moro, Col. 2, lines 40-41, wherein soft magnetic substance layer is intervening between grains, such that the substance would exist on the surface of the non-magnetic oxide layer and therefore in a grain boundary region between consolidated soft magnetic metal particles and be considered a binding material post sintering/consolidation; Col. 2, lines 49-51, wherein high resistance soft magnetic layer bind together the soft magnetic metal particles).
Regarding Claim 16, Moro discloses wherein the soft magnetic metal particle and the interface layer are in direct contact with each other (Moro, Col. 2, lines 39-47; Col. 6, lines 7-12, wherein non-magnetic oxide layer coated directed onto the soft magnetic particle).
Regarding Claim 17, Moro fails to disclose a loss of 1000 kW/m3 when a magnetic field of 0.1T and 50kHz is applied.
However, the structure of Moro and Watanabe is the same as claimed (magnetic particle composition and particle size, interface layer composition and thickness, and a molding density of 95% or higher – see Claim 8 above and teachings of Watanabe regarding interface layer composition), and one of ordinary skill in the art would have expected the dust core of Moro and Watanabe to comprise the claimed range of loss at the claimed parameters because the structure of Moro and Watanabe is identical to the claimed structure.
When 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 has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Claims 13-15 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Moro (previously cited, US 5348800 A) in view of Yoshidome (US 20190279801 A1) and Watanabe (previously cited, US 20220059263 A1), as applied to Claim 12 above and Claim 8 above, respectively, in further view of Herbert (previously cited, US 20210142933 A1).
Regarding Claim 13, Moro does not disclose a binding material comprising glass.
Herbert teaches a similar invention wherein a binding material, which may be a low melting point glass oxide including at least one of B2O3, Bi2O3, V2O5 and combinations thereof, is present as a second layer on the surface of a first insulating layer covering a soft magnetic particle, and therefore present at a grain boundary between soft magnetic grains, in order to facilitate sintering, densification and consolidation of the particles (para. [0135]-[0136]; Fig. 6a-6i).
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 a layer of glass binding material, and one of a low melting point glass oxide including at least one of B2O3, Bi2O3, V2O5 and combinations thereof, as taught by Herbert, for the invention disclosed by Moro, in order to facilitate sintering, densification and consolidation of the particles (see teaching above).
Regarding Claim 14, Herbert discloses wherein the glass of the binding material contains at least one of bismuth, boron and vanadium (para. [0135], at least one of B2O3, Bi2O3 and V2O5).
Regarding Claim 15, Herbert disclose wherein the interface layer and the binding material are in direct contact with each other (para. [0137], wherein second surface glass oxide layer (considered the binding material) is disposed on the first surface layer (interface layer comprising insulating coating)).
Regarding Claim 18, Moro discloses wherein the magnetic core is higher performance usable for high frequency powder sources such as in transformers and choke coils, but fails to disclose using the magnetic core for an inductor.
Herbert teaches wherein soft magnets suitable for use in high performance in pass power electronic components are suitable for use in transformers, choke coils and also inductors (para. [0011]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used the magnetic core of Moro for an inductor, as taught by Herbert, because Moro discloses wherein the magnetic core is usable for high performance in high frequency power sources such as transformers and choke coils, and Herbert teaches these properties are further well suited for an inductor in addition to transformers and choke coils.
Claim 17 is alternatively rejected under 35 U.S.C. 103 as being unpatentable over Moro (previously cited, US 5348800 A) in view of ) in view of Yoshidome (US 20190279801 A1) and Watanabe (previously cited, US 20220059263 A1), as applied to Claim 8 above, in further view of Matsutani (previously cited, US 6063209 A).
Regarding Claim 17, Moro fails to disclose a loss of 1000 kW/m3 when a magnetic field of 0.1T and 50kHz is applied.
Matsutani teaches wherein the selection standard in a choke coil for countermeasure against harmonic distortion is a core loss of 1000kW/m3 or less in the condition of a magnetic field of 0.1T and a frequency of 50Hz (Col. 5, lines 28-24).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have comprised a loss of 1000kW/m3 or less when a magnetic field of 0.1T and 50Hz is applied, as taught by Matsutani, for the invention disclosed by Moro, in order to produce a choke coil (see Moro Col. 10, lines 34-35, disclosing a choke coil) which is up to standard for a choke coil with countermeasure against harmonic distortion (see teaching by Matsutani above).
Response to Arguments
Applicant’s arguments, filed April 20, 2026, with respect to Claims 1 and 3-7, rejected under 35 U.S.C. 102(a)(1) over Kako2017, and rejected under 35 U.S.C. 103 over Uozumi in view of Kako2017 (Claims 8-20) and over Moro in view of Watanabe (Claims 8-20), have been fully considered and are persuasive in view of Applicant’s amendments to the claims further limiting composition of the soft magnetic particle. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made under 35 U.S.C. 103 over Kako2017 in view of Yoshidome, Uozumi in view of Yoshidome and Kako2017 (Claims 8-20), and over Moro in view of Yoshidome and Watanabe (Claims 8-20), as detailed above.
Applicant’s arguments are deemed moot in view of the new grounds of rejection.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Harada (previously cited, US 20080029300 A1): teaches wherein examples of high-frequency magnetic parts include a substrate for an antenna, a magnetic core for transformer, a magnetic head core, an inductor, a choke coil, a filter, and an electromagnetic radiation absorber (para. [0065], magnetic core reads on dust core). Harada further teaches a soft magnetic particle with a size of 5-500nm comprising an insulating coating layer of MoO3 and a binder layer of eutectic crystal oxide, also including MoO3, wherein the insulating coating and binder layer each have a coating of 1-5nm (para. [0030]-[0033]; para. [0039]; para. [0043]-[0044]).
Hosono (previously cited, US 20190279799 A1): teaches a soft magnetic powder with an insulation coating comprising a resistivity of 106 Ωcm or more during a pressurization at 25C and 0.6t/cm2 (about 60Mpa) (Abstract; para. [0097]; para. [0139]).
Watanabe (cited above, US 20220059263 A1, further teachings): teaches a 1-20nm metal oxide passivation layer comprising molybdenum oxide in order to reduce the eddy current loss (para. [0045]; para [0047]), and 25-200nm particle boundary phase in order to improve iron loss, and comprising polycrystalline alumina and a low-melting-point glass in order to fill pores while improving electrical resistance and heat resistance (para. [0050]-[0051]; para. [0063]; para. [0097]).
Watanabe further teaches wherein a thickness of a boundary phase is specifically 10-300nm in order to provide high resistance and reduce the iron loss in a dust core (para. [0038]-[0039]; para. [0062]-[0063]). Watanabe additionally teaches wherein the thickness is controlled by pressure in press forming (para. [0132]).
Herbert (previously cited an cited above, US 20210142933 A1, further teachings): teaches a core soft magnetic metal particle with a continuous dielectric layer, thereby enabling soft magnetic composites with high resistivities, improved core loss, permeability and device efficiency (para. [0128]). Herbert teaches such dielectric coatings comprise a first oxide and/or sulfide layer and a second glassy oxide layer, wherein the first layer is chosen for their high dielectric constant in order to electrically isolate the soft magnetic cores, and wherein the second glassy oxide layer facilitates sintering/densification/consolidation of the particles (para. [0130]; para. [0135]-[0136]).
Herbert teaches wherein suitable oxides for the first layer include molybdenum oxide, in addition to alumina, yttria, magnesium oxide and zirconia, and combinations thereof, and wherein suitable sulfides include molybdenum disulfide (para. [0132]; para. [0138]). Additionally, Herbert teaches wherein a density may range from 90-100%, in order to minimize magnetic loss-inducing air gaps (para. [0197]).
Maeda (previously cited, US 20110285486 A): discloses a dust core (para. [0001]), comprising:
soft magnetic particles, wherein the soft magnetic particles comprise two distributions of sizes of 50-70um and 10-50um (para. [0032]-[0033]; para. [0041]; para. [0049]; Fig. 4, big particles 11 and small particles 21), which reads on the claimed limitations wherein an average particle size is 1-20um (see second, smaller distribution of particle size referenced above; Fig. 4, particles 21);
wherein the particles are coated with an interface layer which exists between particles and comprises a thickness of 10nm-1um (para. [0062]; Fig. 5, insulating coated films 12 and 22 which exist at the interface between particles 11 (big) and 21 (small); para. [0077]), which reads on the claimed range wherein the interface layer thickness is 1-20nm; and wherein
the relative densities are as high as 87% (Table 1, example 1)
Otsuki (US 20110024671 A1): teaches mixing a compacting additive with an insulating compound to coat magnetic particles, wherein the compacting additive may be kaolin or kaolinite, and an insulating layered may be an oxide such as mica (para. [0035]-[0036]).
Dietsch (US 20180294083 A): teaches wherein the Fe-Si-B-Cr-C alloy is an art equivalent of the Fe-Si alloy, Fe-Ni alloy and Fe-Co alloy for a soft magnetic alloy core( para. [0049]).
Matsumoto (US 20210213524 A1): teaches wherein soft magnetic materials capable of forming amorphous Fe-based soft magnetic particles include Fe-Si-B-Cr-C based alloys and Fe-Si-B-Nb based alloys (para. [0012]).
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.
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/CATHERINE P SMITH/ Examiner, Art Unit 1735
/KEITH WALKER/Supervisory Patent Examiner, Art Unit 1735
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