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 .
Election/Restrictions
Applicant’s election without traverse of Group I, claims 1-14, in the reply filed on 7/15/2026 is acknowledged.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention; or
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1-7 and 14 are rejected under 35 U.S.C. 102 (a)(2) as being anticipated by Li et al. (“Li”)(CN 112403695)(with text citations to English translation attached herewith).
Li (fig. 1) teaches a method for removing ultrafine particles from an atomized powder, the method comprising:
(re: claim 1) contacting the atomized powder with a removal liquid to form a mixture of the atomized powder and the removal liquid, the atomized powder comprising fine particles and ultrafine particles (p. 3 teaching in step (1) taking the noble metal powder with a particle size distribution of 1 to 45 mu, putting said metal powder along with a removal liquid-pure water- in primary slurry tank A shown in fig. 1 and then stirring to create a powder slurry, wherein Examiner regards particles in lower mu range as ultrafine, e.g., less than 10 mu);
adding energy to the mixture of the atomized powder and the removal liquid with a liquid classifier system to detach the ultrafine particles from the fine particles (Id. teaching adding energy in step (2) by dispersing the powder via ultrasonic dispersion and/or mechanical stirring as well as a liquid classifier system, hydrocyclone shown near 2 in fig. 1, wherein Examiner particle agglomeration as inherent in atomization process); and
separating, with the liquid classifier system, the removal liquid and the detached ultrafine particles from the fine particles (Id. teaching additional steps (3) to (5) involving transferring powder slurry to additional tanks via booster pumps and then using multi-stage hydraulic cyclones to further separate removal liquid and respective particle at each separation stage with steps (6) and (7) teaching that powder slurry in final separation stage is collected, filtered, dehydrated and dried to obtain powder of which D10 is more than 8 mu and D90 is less than 38 mu; see generally Examples/Embodiments in p. 5-8);
(re: claim 2) wherein the liquid classifier system comprises a cylindrical body including a top and a bottom, a first outlet disposed at the bottom of the cylindrical body, and a second outlet disposed at the top of the cylindrical body (fig. 1 showing hydro cyclone with first outlet near 4 and second outlet near 3; p. 3 teaching multiple hydrocyclone stages that use centrifugal force);
(re: claim 3) wherein separating the removal liquid and the detached ultrafine particles from the fine particles further comprises separating the removal liquid and the detached ultrafine particles with a centrifugal force in the liquid classifier system (Id.);
(re: claim 4) removing the fine particles from the liquid classifier system through the first outlet and removing the removal liquid and the detached ultrafine particles from the liquid classifier system through the second outlet (Id.);
(re: claim 5) sieving a raw metal powder to obtain the atomized powder prior to contacting the atomized powder with the removal liquid (p. 3 teaching that metal powder may be sieved prior to adding of removal liquid/pure water in initial step);
(re: claim 6) after separating the detached ultrafine particles from the fine particles, removing the removal liquid from the fine particles (fig. 1 showing hydrocyclones near 2; p. 3 teaching that underflow—i.e., fine particles and liquid—flow to tank E);
(re: claim 7) wherein removing the removal liquid from the fine particles comprises mechanically removing the removal liquid from the fine particles by at least one of mechanical agitation, filtration, decantation, or centrifugal rotation (Id. teaching cyclone);
(re: claim 14) wherein the atomized powder is a first batch of atomized powder, and wherein the method further comprises:
receiving the separated removal liquid and detached ultrafine particles in a recirculation loop;
filtering the detached ultrafine particles from the removal liquid within the recirculation loop; and
providing the filtered removal liquid to the first batch of atomized powder or to a second batch of atomized powder (fig. 1 showing that multiple separation stages connected in a re-circulation loop thus removal liquid can be seen as re-used in a first or a second batch).
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 of this title, 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 1-7 and 10-14 are rejected under 35 U.S.C. 103 as being unpatentable over Li et al. (“Li”)(CN 112403695) in view of St. Laurent et al. (“Laurent”)(US 2021/0008629) and legal precedent.
Li as set forth above teaches all that is claimed except for expressly teaching
(re: claim 10) wherein a D10 value of the atomized powder prior to removing the ultrafine particles is within 10% of a D10 value of the fine particles;
(re: claim 11) wherein a D50 value of the atomized powder prior to removing the ultrafine particles is within 10% of a D50 value of the fine particles;
(re: claim 12) wherein a D90 value of the atomized powder prior to removing the ultrafine particles is within 10% of a D90 value of the fine particles;
(re: claim 13) wherein the atomized powder contains less than 1800 ppm of oxygen, less than 1000 ppm of carbon, less than 400 ppm of nitrogen, less than 120 ppm of hydrogen, and less than 1000 ppm of chlorine according to AMS 4998.
Further, under an alternative interpretation, the prior art may be interpreted as not having particle attachment (re: claim 1) inherent in the atomization process.
Laurent, however, expressly teaches that it is well-known in the fine powder production arts
- that the atomization process produces particle agglomeration or sticking (para. 110, 112 teaching that atomization process produces satellites, i.e., connected particles);
- that techniques taught by Li that improve the dispersion factor of the powder, e.g., spraying of water, on the atomized particles reduces particle agglomeration (para. 115-116 teaching that addition of water reduces agglomeration as film of water may ensure that “metallic powders or metal droplets are cooled at sufficient temperature to reduce or avoid the sticking of particles, satellites”; provide a controlled level of surface oxidation and reduce electrostatic forces that make sieving difficult; fig. 1 and para. 91, 97-98 teaching that liquid/water may be added via spray nozzles to assist with powder collection and sieving); and
- that the size distribution of the powder is a common design parameter that is influenced by numerous operating variables known to one with ordinary skill in the art (para. 37 teaching that several parameters affect product quality, e.g., size distribution and proportion of coarser and finer particles; see also para. 46, 47, 55, 56 teaching application of atomization and sieving process to variety of reactive metal powders).
Indeed, the claimed features relating to characteristics/type/size distribution of the input powder are common design parameters/operating variables controlled by the design incentives and/or economic considerations involved in this type of subject matter. This is especially applicable in the powder atomization arts as the type of powder to be processed and the desired outputs controls these types variations as demonstrated above. Moreover, legal precedent teaches that variations in these type of common design parameters/operating variables are obvious and are the mere optimization of result-effective variables that would be known to one with ordinary skill in the art. See MPEP 2144.05 I.II (teaching ample motivation to optimize or modify result-effective variables based on “design need(s)” or “market demand”); see also MPEP 2144.04.IV (teaching that changes in size, proportion or shape of known elements are obvious).
It would thus be obvious to one with ordinary skill in the art to modify the base reference with these prior art teachings—with a reasonable expectation of success—to arrive at the claimed invention. The rationale for this obviousness determination can be found in the prior art itself as cited above and in legal precedent as described above. Further, the prior art discussed and cited demonstrates the level of sophistication of one with ordinary skill in the art and that these modifications are predictable variations that would be within this skill level. Therefore, it would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to modify the invention of Li for the reasons set forth above.
Claims 8-9 are rejected under 35 U.S.C. 103 as being unpatentable over Li, Laurent and legal precedent (“Li et al.”) as applied to the claims above, and further in view of what is well known in the art.
Li et al. as set forth above teach all that is claimed except for expressly teaching
(re: claim 8) wherein removing the removal liquid from the fine particles comprises heating the fine particles to evaporate the removal liquid;
(re: claim 9) wherein the removal liquid is a low boiling point liquid having a boiling temperature below 95° C. at a pressure of 1 atmosphere.
Here, it is noted that Laurent already teaches
that the powder collection stage involves drying the sieved powder (para. 80, 81, 92 teaching post processing includes drying stages under vacuum or inert gas); and
that the spray water characteristics should be altered to prevent oxidation (para. 118-120 teaching that additives, such as ethanol, methanol, acetic acid or inorganic reductants, can be added to water to control level of oxidation).
Indeed, Examiner takes Official Notice that the feature of drying involves heat and that the use of additive that controls the level of oxidation also lowers the specific boiling point of the removal liquid below 95c are well-known in powder atomization and production arts.
It would thus be obvious to one with ordinary skill in the art to modify the combination of references with these prior art teachings—with a reasonable expectation of success—to arrive at the claimed invention as these modifications are already well-known and commonly implemented in the powder atomization and production arts. Therefore, it would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to modify the invention of Li et al. for the reasons set forth above.
Conclusion
Any references not explicitly discussed above but made of record are regarded as helpful in establishing the state of the prior art and are thus considered relevant to the prosecution of the instant application.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOSEPH C RODRIGUEZ whose telephone number is 571-272-3692 (M-F, 9 am – 6 pm, PST). The Supervisory Examiner is MICHAEL MCCULLOUGH, 571-272-7805.
Alternatively, to contact the examiner, send an E-mail communication to Joseph.Rodriguez@uspto.gov. Such E-mail communication should be in accordance with provisions of the MPEP (see e.g., 502.03 & 713.04; see also Patent Internet Usage Policy Article 5). E-mail communication must begin with a statement authorizing the E-mail communication and acknowledging that such communication is not secure and may be made of record. Please note that any communications with regards to the merits of an application will be made of record. A suggested format for such authorization is as follows: "Recognizing that Internet communications are not secure, I hereby authorize the USPTO to communicate with me concerning any subject matter of this application by electronic mail. I understand that a copy of these communications will be made of record in the application file”.
Information regarding the status of an application may also be obtained from the Patent Center: https://patentcenter.uspto.gov/
/JOSEPH C RODRIGUEZ/Primary Examiner, Art Unit 3655
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August 27, 2026
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