DETAILED ACTION
Response to Amendment
The Amendment filed 18 May 2026 has been entered. Claims 1-3 and 5-20 remain pending in the application. Claims 13-20 have been withdrawn. Claim 4 has been canceled. No new claims have been added.
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 28 September 2023 was considered by the examiner. The submission is in compliance with the provisions of 37 CFR 1.97.
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, 2 and 5-10 are rejected under 35 U.S.C. 103 as being unpatentable over US2016023276 of Mochizuki in view of US2020027657 of Yang, and further in view of CN101767200 (machine translation) of Zhimeng.
Claim 1 claims a method for recycling a rare earth element-containing powder, comprising: disintegrating a molded body for a rare earth sintered magnet comprising a rare earth element-containing powder in oil such that a 149 mesh-pass, 500 mesh-on powder is included; and separating and collecting a 149 mesh-pass powder out of a powder obtained after the disintegrating to obtain a recycled powder; wherein the rare earth element-containing powder is an alloy powder comprising: R: at least one selected from the group consisting of Nd, Pr, Dy, Tb, Ce and La; T: Fe, or Fe and Co; and B.
Mochizuki teaches a slurry recycling method, producing method of rare earth sintered magnet and slurry recycling apparatus in the same field of endeavor as the claimed invention. Mochizuki discloses the pulverization, equivalent to disintegrating, and recycling of rare earth molded bodies, Para[0001],[0005]. Mochizuki teaches that the powder before molding is put into oil to form slurry, Para[0005]. Mochizuki teaches that it is preferable that alloy powder for a rare earth sintered magnet is raw material alloy for an R-T-B-based sintered magnet, and preferably an R—Fe(Co)—B-M-based alloy. Here, R is selected from at least one kind of Nd, Pr, Dy and Tb. It is preferable that R includes at least one kind of Nd and Pr. More preferably, a combination of rare earth elements represented by Nd—Dy, Nd—Tb, Nd—Pr—Dy or Nd—Pr—Tb is used. Here, Dy and Tb among R exert an enhancing effect of a coercive force, Para[0084],[0085]. Mochizuki does not teach a 149 mesh-pass, 500 mesh-on powder, and does not specifically mention separating and collecting the recycled powder.
Yang teaches a method of increasing the coercivity of a sintered Nd-Fe-B permanent magnet in the same field of endeavor as the claimed invention. Yang discloses that the powder has a particle size of between 100 mesh and 500 mesh, Para[0009]. This overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Yang teaches that the present invention also controls the particle size range of the heavy rare earth powder thereby controlling the heavy rare earth content adhering to the surface of the sintered Nd—Fe—B permanent magnet such that the precision of the heavy rare earth content is higher. The present invention further prevents impurities from being introduced into the sintered Nd—Fe—B permanent magnet, Para[0007].
Zhimeng discloses a minute spherical Nd-Fe-B powder preparation method in the same field of endeavor as the claimed invention. Zhimeng teaches that the fine spherical neodymium-iron-boron powder is collected by cyclone separation, Para[0020]. Zhimeng discloses that magnetic powder is the core part of manufacturing high-performance bonded magnets. The performance of magnetic powder has a great influence on the magnetic performance of the final product. The performance of magnetic powder is closely related to its preparation method (i.e. separating and collecting), particle shape, particle size, and particle size distribution, Para[0004]
Therefore, it would be obvious to one of ordinary skill in the art to produce the recycled powder disclosed in Mochizuki with the powder size taught in Yang, and the separation and collection taught in Zhimeng in order to control the heavy rare earth content such that impurities are avoided, and to ultimately achieve better magnetic performance. Thus, Mochizuki in view of Yang further in view of Zhimeng covers all limitations of claim 1.
Claim 2 further limits claim 1 by claiming that the powder obtained after the disintegrating comprises a 500 mesh-on powder at a proportion of 10% by mass or more.
Yang discloses a particle size of between 100 mesh and 500 mesh, Para[0009]. This roughly corresponds to a particle size range of 30 µm to 149 µm, as these are the well-known sizes of the holes in the 100 mesh and 500 mesh sieves common to the art. Furthermore, in paragraph [0069] of the instant specification, applicant defines “500 mesh-on” powder as powder that remains on a 500-mesh sieve (opening: 25 µm). Thus, claim 2 is claiming a powder where a proportion of 10% by mass or more of the particles are in the range of 25 µm to 149 µm. As Yang discloses that all particles fall within the range of 30 µm to 149 µm, the prior art range overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Yang teaches that the present invention also controls the particle size range of the heavy rare earth powder thereby controlling the heavy rare earth content adhering to the surface of the sintered Nd—Fe—B permanent magnet such that the precision of the heavy rare earth content is higher. The present invention further prevents impurities from being introduced into the sintered Nd—Fe—B permanent magnet, Para[0007]. Thus, it would be obvious to one of ordinary skill in the art to produce the recycled powder, with particle size ranging from 30 µm to 149 µm in order to increase the precision of the heavy rare earth content and further prevent impurities. Thus, Mochizuki in view of Yang further in view of Zhimeng covers all limitations of claim 2.
Claim 5 further limits claim 1 by claiming that the alloy powder comprises: the R: 27% by mass or more and 33% by mass or less; and the B: 0.9% by mass or more and 1.2% by mass or less; with the balance consisting of the T and inevitable impurities.
Mochizuki teaches a slurry recycling method, producing method of rare earth sintered magnet and slurry recycling apparatus in the same field of endeavor as the claimed invention. Mochizuki teaches a range for R of 25% by mass or more and 35% by mass or less, Para[0086], T absolutely includes Fe, and 50% by mass thereof can be replaced by Co, Para[0087], and a preferable range of the content of B is between 0.9% by mass and 1.2% by mass, Para[0088]. The prior art ranges for R, T, and B overlap with the claimed ranges. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Thus, Mochizuki in view of Yang further in view of Zhimeng covers all limitations of claim 5.
Claim 6 further limits claim 1 by claiming that the R is at least one selected from the group consisting of Nd, Pr, Dy and Tb.
Mochizuki teaches a slurry recycling method, producing method of rare earth sintered magnet and slurry recycling apparatus in the same field of endeavor as the claimed invention. Mochizuki discloses that here, R is selected from at least one kind of Nd, Pr, Dy and Tb, Para[0085]. Thus, Mochizuki in view of Yang further in view of Zhimeng covers all limitations of claim 6.
Claim 7 further limits claim 1 by claiming that R comprises at least one selected from the group consisting of Nd and Pr.
Mochizuki teaches a slurry recycling method, producing method of rare earth sintered magnet and slurry recycling apparatus in the same field of endeavor as the claimed invention. Mochizuki discloses that here, R is selected from at least one kind of Nd, Pr, Dy and Tb, Para[0085]. Mochizuki also teaches that it is preferable that R includes at least one kind of Nd and Pr, Para[0085]. Thus, Mochizuki in view of Yang further in view of Zhimeng covers all limitations of claim 7.
Claim 8 further limits claim 1 by claiming that the Co content in the T is 50 % by mass or less.
Mochizuki teaches a slurry recycling method, producing method of rare earth sintered magnet and slurry recycling apparatus in the same field of endeavor as the claimed invention. Mochizuki discloses that T absolutely includes Fe, and 50% by mass thereof can be replaced by Co, Para[0087]. Thus, Mochizuki in view of Yang further in view of Zhimeng covers all limitations of claim 8.
Claim 9 further limits claim 1 by claiming that a part of the B is replaced with C.
Mochizuki teaches a slurry recycling method, producing method of rare earth sintered magnet and slurry recycling apparatus in the same field of endeavor as the claimed invention. Mochizuki discloses that a portion of B can be replaced by C. By the replacement of C, it is possible to enhance a corrosion resistance of a magnet and this is effective, Para[0088]. Thus, Mochizuki in view of Yang further in view of Zhimeng covers all limitations of claim 9.
Claim 10 further limits claim 5 by claiming that the alloy powder further comprises more than 0% by mass and 5.0% by mass or less of M which is at least one element selected from the group consisting of Al, Si, Ti, V, Cr, Ni, Cu, Zn, Ga, Zr, Nb, Mo, In, Sn, Hf, Ta, and W.
Mochizuki teaches a slurry recycling method, producing method of rare earth sintered magnet and slurry recycling apparatus in the same field of endeavor as the claimed invention. Mochizuki discloses that in addition to the above-described elements, M element can be added to enhance the coercive force. The M element is at least one kind of Al, Si, Ti, V, Cr, Mn, Ni, Cu, Zn, Ga, Zr, Nb, Mo, In, Sn, Hf, Ta and W. The additive amount is preferably 2% by mass or less. If the additive amount exceeds 5% by mass, the residual magnetic flux density is lowered, Para[0089]. Thus, Mochizuki in view of Yang further in view of Zhimeng covers all limitations of claim 10.
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over US2016023276 of Mochizuki in view of US2020027657 of Yang further in view of CN101767200 (machine translation) of Zhimeng , taken as cited above, still further in view of WO2019084045 of Lin.
Claim 3 further limits claim 2 by claiming that the rare earth element-containing powder comprises the 500 mesh-on powder at a proportion of 50% by mass or more.
Mochizuki teaches a slurry recycling method, producing method of rare earth sintered magnet and slurry recycling apparatus in the same field of endeavor as the claimed invention. Yang teaches a method of increasing the coercivity of a sintered Nd-Fe-B permanent magnet in the same field of endeavor as the claimed invention. Zhimeng discloses a minute spherical Nd-Fe-B powder preparation method in the same field of endeavor as the claimed invention. Mochizuki, Yang, and Zhimeng do not teach a proportion of 50% by mass or more of 500 mesh-on powder for the rare earth element-containing powder.
Lin teaches electrolytic based methods for recycling titanium particles in a similar field of endeavor as the claimed invention. Lin discloses rare earths as feedstock material, Para[0070], with as received particles having a D50 ranging from 10 µm to 150 µm, Para[0032]. Lin discloses that these feedstocks may be used to produce purified feedstock, Para[0070]. Furthermore, in paragraph [0069] of the instant specification, applicant defines “500 mesh-on” powder as powder that remains on a 500-mesh sieve (opening: 25 µm). Thus, claim 3 is claiming that a proportion of 50% by mass or more of the rare earth element-containing powder particles are in the range of 25 µm to 149 µm. Thus, the claimed range overlaps with the prior art range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Therefore, it would be obvious to one of ordinary skill in the art to produce the rare earth element containing powder disclosed in Mochizuki, Yang, and Zhimeng with the particle size disclosed in Lin in order to produce purified feedstock. Thus, Mochizuki in view of Yang further in view of Zhimeng further in view of Lin covers all limitations of claim 3.
Claims 11 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over US2016023276 of Mochizuki in view of US2020027657 of Yang further in view of CN101767200 (machine translation) of Zhimeng, taken as cited above, still further in view of CN112563009 (machine translation) of Zhu.
Claim 11 further limits claim 1 by claiming that a particle diameter D50 of the rare earth element-containing powder is 1.0 µm or more and 10.0 µm or less.
Mochizuki teaches a slurry recycling method, producing method of rare earth sintered magnet and slurry recycling apparatus in the same field of endeavor as the claimed invention. Yang teaches a method of increasing the coercivity of a sintered Nd-Fe-B permanent magnet in the same field of endeavor as the claimed invention. Zhimeng discloses a minute spherical Nd-Fe-B powder preparation method in the same field of endeavor as the claimed invention. While Mochizuki teaches a D50 value of 4.76 µm, Para[0172], Yang and Zhimeng do not teach a value for D50.
Zhu teaches a method for preparing sintered magnet by utilizing recycled compact in the same field of endeavor as the claimed invention. Zhu discloses a D50 particle size of 3.0-6.0 μm, Para[0017]. This overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Zhu teaches that since the bonding force between the compact powders is weak, choosing a variable frequency disc dispersing device can achieve the purpose of crushing the compact into powder, and at the same time, it can try to keep the powder particle size close to the raw material powder particle size after crushing, and no further powder will be produced. To solve the problem, reduce the proportion of ultra-fine powder and improve the utilization rate of powder. In addition, reducing the degree of powder refinement facilitates the subsequent use of powder remanence for the granulation process, because the powder particle size is too small, and the unit area remanence retention is reduced, and the granulation effect cannot be achieved, Para[0052]. Thus, based on the teaching of Mochizuki and Zhu, it would be obvious to one of ordinary skill in the art to produce the recycled powder using a rare earth element containing powder with the D50 value of 3.0-6.0 µm in order to reduce the degree of powder refinement and achieve the desired granulation effect. Therefore, Mochizuki in view of Yang further in view of Zhimeng further in view of Zhu covers all limitations of claim 11.
Claim 12 further limits claim 11 by claiming that the particle diameter D50 is 2.0 µm or more and 5.0 µm or less.
Mochizuki teaches a slurry recycling method, producing method of rare earth sintered magnet and slurry recycling apparatus in the same field of endeavor as the claimed invention. Yang teaches a method of increasing the coercivity of a sintered Nd-Fe-B permanent magnet in the same field of endeavor as the claimed invention. Zhimeng discloses a minute spherical Nd-Fe-B powder preparation method in the same field of endeavor as the claimed invention. While Mochizuki teaches a D50 value of 4.76 µm, Para[0172], Yang and Zhimeng do not teach a value for D50.
Zhu teaches a method for preparing sintered magnet by utilizing recycled compact in the same field of endeavor as the claimed invention. Zhu discloses a D50 particle size of 3.0-6.0 μm, Para[0017]. This overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists, see MPEP 2144.05. Zhu teaches that since the bonding force between the compact powders is weak, choosing a variable frequency disc dispersing device can achieve the purpose of crushing the compact into powder, and at the same time, it can try to keep the powder particle size close to the raw material powder particle size after crushing, and no further powder will be produced. To solve the problem, reduce the proportion of ultra-fine powder and improve the utilization rate of powder. In addition, reducing the degree of powder refinement facilitates the subsequent use of powder remanence for the granulation process, because the powder particle size is too small, and the unit area remanence retention is reduced, and the granulation effect cannot be achieved, Para[0052]. Thus, based on the teaching of Mochizuki and Zhu, it would be obvious to one of ordinary skill in the art to produce the recycled powder using a rare earth element containing powder with the D50 value of 3.0-6.0 µm in order to reduce the degree of powder refinement and achieve the desired granulation effect. Therefore, Mochizuki in view of Yang further in view of Zhimeng further in view of Zhu covers all limitations of claim 12.
Response to Arguments
Applicant's arguments filed 18 May 2026 have been fully considered but they are not persuasive. Applicant argues that (remarks, page 9 of 11) amended claim 1 differs in composition from Yang’s heavy rare earth powder because Yang’s heavy rare earth powder is not intended to include Nd, Fe and B already present in the Nd-Fe-B based sintered magnet. This is not found persuasive as Yang teaches that the least one heavy rare earth element is selected from a group consisting of Tb, Dy, a chemical compound containing Tb or Dy, or an alloy containing Tb or Dy, Para[0009]. The composition of claim 1 would include Tb-Fe-B alloys and Dy-Fe-B alloys as they are alloys containing Tb or Dy. Therefore, Yang’s heavy rare earth powder composition would meet the limitations of the composition of claim 1 of the instant invention.
Additionally, this argument is moot because the composition of claim 1 is disclosed by primary reference Mochizuki. The disclosure of Yang is used for its particle size teachings. Applicant argues that (remarks, page 9 of 11) there is no motivation to apply Yang’s particle size to Mochizuki’s powder. This is not found persuasive as Yang discloses that the present invention also controls the particle size range of the heavy rare earth powder thereby controlling the heavy rare earth content, and that the present invention further prevents impurities from being introduced, Para[0007]. Therefore, one of ordinary skill in the art would be able to consider this particle size in Yang as a possible particle size for the powder disclosed by Mochizuki in order to prevent impurities in the products made with the recycled powder. Therefore, there is clear motivation to produce the recycled powder disclosed in Mochizuki with the particle size taught by Yang.
Applicant argues that (remarks, page 10 of 11) since Mochizuki’s examples result in almost no change in saturation flux density between the recycled slurry and the new slurry, and since Yang’s heavy rare earth powder results show a decrease in remanence that it would be impossible to achieve better magnetic performance by applying Yang’s heavy rare earth powder. This is not found persuasive as one of ordinary skill in the art would still be motivated to use the particle size taught by Yang even though Yang shows a decrease in remanence because Yang teaches that the particle size prevents impurities from being introduced, Para[0007]. Yang teaches that the present invention allows the user to control the amount of the heavy rare earth elements that are being used during the diffusion process thereby improving the utilization rate of the heavy rare earth elements, Para[0021]. Therefore, even though a non-preferred decrease in remanence would occur, it would still be obvious to one of ordinary skill in the art to apply the particle size of Yang to Mochizuki in order to prevent impurities in the final product by improving the utilization rate of the heavy rare earth elements. A reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including nonpreferred embodiments, see MPEP 2123. Thus, it would be obvious to apply Yang’s heavy rare earth powder particle size to Mochizuki’s alloy.
Therefore, the rejection is maintained.
Examiner’s Note
Examiner has attached previously-cited foreign references that were inadvertently omitted in the non-final action. References Included: CN101767200, WO2019084045, and CN112563009.
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.
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/JACOB BENJAMIN STILES/Examiner, Art Unit 1733
/VANESSA T. LUK/Primary Examiner, Art Unit 1733
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