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 .
Continued Examination Under 37 CFR 1.114
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 12/04/2025 has been entered.
Status of Claims
Claim 1 is amended. Claim 3 is cancelled. Claims 6-14 are withdrawn. Claims 1-2, 4-5 and 15-17 are examined herein.
Status of Previous Rejections
The rejections of claim 1-2, 4-5 and 15-17 under 35 U.S.C. 103 as being unpatentable over Sagawa (US 2014/0327503), and further in view of US’525 (US 2015/0059525) and Tsubokura (US 2010/0233016) are maintained.
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.
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.
Claims 1-2, 4-5 and 15-17 are rejected under 35 U.S.C. 103 as being unpatentable over Sagawa (US 2014/0327503), and further in view of US’525 (US 2015/0059525) and Tsubokura (US 2010/0233016).
Regarding claims 1 and 15, Sagawa teaches a sintered R-Fe-B magnet having average crystal grain size of 2.6-2.9 µm and a degree of orientation (OR) of 96.6 % ([0075]; Table 3, Example 4). When the grain size is 2.6 µm, 0.7x2.6+95=96.82, which is very close to the OR of Example 4 in Table 1. A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). See MPEP 2144.05 I. Thus, the recited formula (2) is a prima facie case of obviousness over Sagawa.
Sagawa discloses that the carbon amount is 1000 ppm or less (Abstract), which overlaps the recited amount of carbon in claim 1. Thus, the recited amount of carbon is prima facie case of obviousness over Sagawa. See MPEP 2144.05 I. Sagawa does not teach the recited amount of O and N. US’525 teaches an R-T-B sintered magnet and discloses that in order to make a magnet having high magnetic properties while preventing generation of a coarse grain, the oxygen content is set to 500 ppm or more, the nitrogen content is set to 150 ppm or more and the carbon content is set to 500 ppm or more with a total amount of C+O+N in the range of 1150 ppm to 3000 ppm (Abstract; [0062]). Thus, it would be obvious to one of ordinary skill in the art to make a R-T-B magnet containing 500 ppm or more oxygen, 150 ppm or more nitrogen and 500 ppm or more carbon with a total amount of C+O+N in the range of 1150 ppm to 3000 ppm as taught by US’525 in the process of Sagawa in order to make a magnet having high magnetic properties and fine grain size as disclosed by US’525. US’525 discloses an example containing 950 ppm carbon, 820 ppm oxygen and 170 ppm nitrogen ([0063]), which meets the recited amount of carbon, oxygen and nitrogen in claim 1.
Sagawa in view of US’525 does not teach the magnet contains Zr. Tsubokura teaches an RTB magnet and discloses that 0.03-0.25 mass% Zr (i.e. 0.47 at%) is added to prevent grain growth during sintering (Abstract; [0032]). Thus, it would be obvious to one of ordinary skill in the art to add 0.03-0.25 mass% Zr as taught by Tsubokura in the magnet of Sagawa in view of US’525 in order to prevent grain growth during sintering as disclosed by Tsubokura. Tsubokura discloses many examples containing 0.19-0.25 wt% Zr and the examples have excellent Br, Hcj and squareness ratio (Table 1, Example 20). Assuming adding 0.2 mass% Zr in Example 4 of Sagawa, the magnet contains 22 mass% Nd, 5.17 mass% Pr, 3.88 mass% Dy, 0.95 mass% B, 0.11 mass% Cu, 0.21 mass% Al, 0.99 mass% Co, 0.2 mass% Zr and the balance being Fe, which converts to 10.0347 at% Nd, 2.413915 at% Pr, 1.570911 at% Dy, 5.781373 at% B, 0.103832 at% Cu, 0.512057 at% Al, 1.105842 at% Co, 0.144243 at% Zr and the balance being Fe. [B]-2[X]=5.493, which meets formula (3) recited in claim 1. Example 4 in Table 1 of Sagawa contains 14.02 at. % R, which is very close to the recited amount of R in claim 1. A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). See MPEP 2144.05 I. Thus, claim 1 is obvious over Sagawa in view of US’525 and Tsubokura.
Regarding claim 2, Tsubokura teaches an RTB magnet and discloses that 0.03-0.25 mass% Zr (i.e. 0.47 at%) is added to prevent grain growth during sintering (Abstract; [0032]). Tsubokura discloses an example containing 0.25 wt% Zr and the example has excellent Br, Hcj and squareness ratio (Table 1, Example 20). Assuming adding 0.25 mass% Zr in the magnet of Sagawa in Example 4, the magnet contains 22 mass% Nd, 5.17 mass% Pr, 3.88 mass% Dy, 0.95 mass% B, 0.11 mass% Cu, 0.21 mass% Al, 0.99 mass% Co, 0.25 mass% Zr and the balance being Fe, which converts to 10.037 at% Nd, 2.414 at% Pr, 1.571 at% Dy, 5.783 at% B, 0.104 at% Cu, 0.512 at% Al, 1.106 at% Co, 0.180 at% Zr and the balance being Fe. [B]-2[X]=5.422, which is close to the range defined by formula (3) recited in claim 2. A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). See MPEP 2144.05 I. Thus, claim 2 is obvious over Sagawa in view of US’525 and Tsubokura.
Further, Example 20 of Tsubokura has B-2x[X]=5.1 (calculated by the Examiner after unit conversion), which meets Formula (3’) recited in claim 2.
Regarding claim 4, Sagawa discloses that the magnet may contains 0.29-3.88 mass% Dy (Table 1), which overlaps the recited composition in claim 4. 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. Thus, claim 4 is obvious over Sagawa in view of US’525 and Tsubokura.
Regarding claim 5, Sagawa discloses that Tb is diffused into the grain boundary of the sintered magnet ([0082] to [0085]), which meets the limitation recited in claim 5.
Regarding claim 16, Sagawa discloses that the amount of carbon is 1000 ppm or less (Abstract), which is close to the recited amount of carbon in claim 16. A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). See MPEP 2144.05 I. Thus claim 16 is obvious over Sagawa in view of US’525 and Tsubokura.
Regarding claim 17, Sagawa discloses that the average grain size is 4.5 µm or less (Abstract), which overlaps the recited grain size in claim 17. 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. Thus, claim 17 is obvious over Sagawa in view of US’525 and Tsubokura.
Response to Arguments
Applicant’s arguments dated 12/04/2025 have been considered but they are not persuasive.
First, the applicants argued: the R content in claim 1 (as amended) is "12.5 to 14.0 atom%", which does not overlap with the R content of Sagawa et al. US '503. In Sagawa et al. US '503, only four element compositions are disclosed in Table 1 regarding the R content. Among the compositions in Table 1, composition 4, which the Examiner pointed out, has the lowest R content. Even in composition 4, the R content is 14.4 atom %, which is outside the scope of the present invention.
In response, Example 4 of Sagawa contains 22 mass% Nd, 5.17 mass% Pr, 3.88 mass% Dy, 0.95 mass% B, 0.11 mass% Cu, 0.21 mass% Al, 0.99 mass% Co, 0.2 mass% Zr and the balance being Fe, which converts to 10.02554 at% Nd, 2.411713 at% Pr, 1.569478 at% Dy, 5.776099 at% B, 0.103738 at% Cu, 0.51159 at% Al, 1.104833 at% Co, and the balance being Fe. The total amount of R is 14.0067 at%, which is very close to range of R recited in claim 1. A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). See MPEP 2144.05 I. Thus, claim 1 is obvious over Sagawa in view of US’525 and Tsubokura.
Second, the applicants argued that in the present invention, due to the claimed R content (lower atom %), the crystallization of α-Fe is suppressed, sufficient densification is achieved, and a decrease in Br is prevented. In particular, the upper limit of 14.0 atom% prevents a decrease in Br due to a low proportion of the R2Fe14B phase. Sagawa et al. US '503 fails to disclose or suggest any of these findings or considerations.
In response, Br is not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993). Further, the amount of R in Composition 4 disclosed by Sagawa is only 0.0067 at. % more than the claimed range. It would be obvious to one of ordinary skill in the art that such little difference in R would not reduce Br.
Conclusion
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Xiaowei Su whose telephone number is (571)272-3239. The examiner can normally be reached 8:00-5:00.
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/XIAOWEI SU/Primary Examiner, Art Unit 1733