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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 June 11, 2026 has been entered.
Response to Amendments and Status of Claims
Applicant’s amendments to the claims, filed May 19, 2026, are acknowledged. Claims 1, 15 and 20 are amended, and Claims 4 and 7 are canceled.
Claims 1-2, 5-6, 8-15 and 17-20 are pending and currently considered in this office action.
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.
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.
Claim 1-2, 5-6, 9-12, 14-15, 17 and 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Gong (previously cited and cited by Applicant in IDS filed July ,17, 2025, “Synthesis and characterization of structural and optical properties of Ce, U codoped YAG transparent ceramics”) in view of Chang (previously cited, US 20220242793 A1).
Regarding Claim 1, Gong discloses a method for fabricating U-doped YAG material comprising:
mixing solid alumina, yttria and uranyl nitrate in stoichiometric amounts, which reads on claimed step (a) of preparing a powder mixture by combining solid yttria powder, alumina powder, and the fissionable isotope in stoichiometric ratios (Experimental procedure, Al2O3, Y2O3, uranyl nitrate (reads on fissionable isotope), and weighted according to stoichiometric formula; chemicals were mixed in a required ratio and ball milled),
ball milling in a solvent for 24 hours, which reads on the claimed step (b) grinding the powder mixture to form a first milled powder, and
drying in an oven and sieving through a mesh, which reads on the claimed step (c) drying the first milled powder,
Gong fails to disclose the steps of:
(d) calcinating the first milled powder at around 1100C so that a yttrium garnet phase is formed, thereby forming a calcinated powder,
(e) grinding the calcinated powder to form a second milled powder including performing a second ball milling process, and
(f) drying the second milled.
Chang teaches performing a powder calcining step at 1100C prior to sintering, wherein the calcining step may be repeated up to three times, in order to completely form the YAG phase as a powder, thereby allowing the formation a final, dense YAG phase product which can advantageously be sintered at a lower sintering temperature with improved yield (para. [0065], calcining is repeated, up to three times; para. [0056], calcining at 1100-1650C to form a YAG phase; para. [0019], previous solid state methods require high sintering temperatures, 1600C or greater, to achieve high density articles (Gong teaches 1900C); para. [0023], YAG phase powder sinters to a higher density at a lower sintering temperature; para. [0035], providing complete YAG phase formation in calcining process; para. [0072], sintering temperatures as low as 1500C; para. [0096], wherein repeated calcining produces complete YAG phase transformation, whereas one calcination step is insufficient). Chang teaches that calcining at lower temperatures avoids sintering, and one of ordinary skill in the art would appreciate calcining at the low end of the range taught by Chang (1100C), in order fully avoid sintering of the powder prior to intended final sintering and densification (para. [0056]).
Chang teaches wherein the repeated calcining cycle includes ball milling, spray drying, compacting and calcining at 1100C (para. [0065], calcining is repeated…the repeated cycles may include…ball milling, spray drying, and compacting in each repeated cycle). Chang also teaches that the calcining cycles are followed by a final milling (automilling), drying, shaping and sintering to final article, and wherein a organics burnout cycle may be included (Fig. 1, steps 160 and 170; para. [0066], finished calcined powder subjected to final milling, drying, compacting and sintering; para. [0092], dried powder is uniaxial pressed and sintered; para. [0064], the organic burnout cycle equates to the 800C calcining cycle of Gong which removes organism (organics)).
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 the calcining steps of Chang, including repeating a calcining cycle up to three times, wherein the calcining cycle comprises ball milling, drying, compacting and calcinating at 1100C, and wherein the calcining steps are performed prior to shaping and sintering, as taught by Chang, for the invention disclosed by Gong. One would be motivated to do this in order to ensure and maximize the transformation of the YAG phase in the powder, thereby allowing for reduced sintering temperatures for dense products and increased yields (see teachings by Chang above). Further, one would also be motivated to specifically calcine the powder at 1100C in order to avoid unwanted sintering prior to final densification (see teachings by Chang above).
One of ordinary skill in the art would appreciate that Gong forms the YAG phase insitu during sintering (the calcining step described by Gong is for organic material burn off) which limits the control and amount of the YAG phase formed. Therefore, one of ordinary skill in the art would recognize that the teachings of Chang also allow for improved control and maximized YAG phase formation in the final product in addition to forming higher density articles at reduced sintering temperatures (see teachings by Chang above).
The invention according to Gong in view of Chang, for example, includes performing calcining and repeating the calcining cycle, wherein the calcining cycle includes ball milling, drying and compacting, and therefore would include the following steps: powder mixing, (first) ball milling, drying (or spray drying), compacting, first calcining, second calcining cycle (i.e., (second) ball milling, spray drying, compacting, second calcining), final automilling, drying, compacting, and sintering at a temperature lower than Gong (1500-1800C vs 1900C). Thus, the invention of Gong in view of Chang read on the claimed steps requiring (d) calcinating the first milled powder at around 1100C so that a yttrium garnet phase is formed, thereby forming a calcinated powder, (e) grinding the calcinated powder to form a second milled powder including performing a second ball milling process, and (f) drying the second milled.
Gong further discloses forming a compact, heating to remove organisms (organics), and further pressing the compact using CIP and sintering, which reads on claimed step of (f) shaping to form a shaped material portion and (g) sintering the shaped material portion (Section 2, experimental procedure; uranyl nitrate reads on fissionable isotope; see also Chang, para. [0092]).
While Gong does not disclose forming a plurality of shaped material portions as claimed (see steps g-h), such a modification would amount to a mere duplication of parts, and it has been held that a duplication of the essential working parts involves only routine skill in the art (see MPEP 2144.04.VI.B). One would be motivated to shape and sinter a plurality of shaped material portions in order to mass produce the sintered bodies.
Gong in view of Chang therefore teach the claimed limitations of steps (a)-(h).
Regarding Claim 2, Gong discloses wherein the fissionable isotope includes a uranium isotope (Experimental procedure, uranyl nitrate reads on uranium isotope; see also instant specification para. [0113], wherein uranyl nitrate is used).
Regarding Claim 5, Gong and Chang disclose wherein grinding the powder mixture to form the milled powder includes performing a first ball milling process (Gong, Experimental procedure, mixed in a require ratio for ball milling in solvent for 24h; Chang, para. [0037], ball milling of the powder mixture).
Regarding Claim 6, Chang discloses sieving the powder slurry after ball milling and prior to drying in order to separate coarse particulates from the powder slurry and to remove the grinding media, which reads on the claim language of prior to drying the first milled powder, straining the first milled powder (para. [0086]; sieving reads on the broadest most reasonable interpretation of straining).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have sieved the first milled powder prior to drying, and therefore strained the first milled powder prior to drying as claimed, as taught by Chang, for the invention disclosed by Gong, in order to remove agglomerates and grinding media from the powder slurry (see teachings above).
Regarding Claim 9, Chang discloses calcining the dried powder from 1100-1650C for 2-64 hours, and wherein the calcining cycle may be repeated, such that the powder is subjected to another cycle of ball milling, drying, compacting and calcining (para. [0065]; see teaching above in Claim 1). One of ordinary skill in the art would appreciate that ball milling and handling of the powders before and after calcining would occur at room temperature because Chang does not disclose heating for ball milling and/or compacting. Therefore, the powders would necessarily be heated from room temperature to the calcining temperature and then cooled to room temperature from the calcining temperature, which reads on the claimed steps wherein calcinating the first milled powder includes (i) heating the first milled powder from approximately room temperature to above 1000C, (ii) holding the first milled powder at a dwell temperature above 1000C for a dwell time period, and (iii) cooling from the dwell temperature to approximately room temperature.
Regarding Claim 10, Chang discloses wherein the dwell time period is greater than 5 hours (para. [0057], 2-64 hours). 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.
Regarding Claim 11, Chang discloses straining the finally milled powder prior to shaping, and therefore straining the second milled powder because the second milled powder is subjected to the final milling (para. [0066]-[0069], wherein the finally calcined YAG compact is then automilled and sieved before drying and therefore prior to shaping and sintering – see para. [0072] wherein powder is shaped into final product and sieving and drying; sieving reads on the broadest most reasonable interpretation of straining).
Further, Chang also discloses sieving the powder slurry after ball milling and prior to drying as part of the calcination cycles, in order to separate coarse particulates from the powder slurry and to remove the grinding media, which reads on the claim language of prior to drying the second milled powder (during repeated calcination cycle), straining the second milled powder (para. [0086]; sieving reads on the broadest most reasonable interpretation of straining).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have sieved the second milled powder prior to drying as part of the repeated calcination cycle, and therefore strained the second milled powder prior to drying as claimed, as taught by Chang, for the invention disclosed by Gong, in order to remove agglomerates and grinding media from the powder slurry (see teachings above).
Regarding Claim 12, Chang discloses wherein shaping the second milled powder includes activating a uniaxial press such as a hydraulic press, wherein the plurality of shaped material portions form one or more cylinders or pellets of the second milled powder (para. [0051]-[0052], uniaxial pressing with hydramet, which is a hydraulic press; grinding media shapes would be a cylinder or pellet; para. [0092], shaping with the uniaxial press prior to sintering; see Claim 1 above wherein it would be obvious to manufacture a plurality of compacts).
Regarding Claim 14, Gong discloses using a tungsten heating element vacuum furnace for sintering (section 2, Experimental procedure), which reads on activating a tungsten mesh vacuum furnace as claimed.
Regarding Claim 15, Gong discloses a method for fabricating U-doped YAG material comprising:
mixing solid alumina, yttria and uranyl nitrate in stoichiometric amounts, which reads on claimed step (a) of preparing a powder mixture by combining solid yttria powder, alumina powder, and the fissionable isotope in stoichiometric ratios (Experimental procedure, Al2O3, Y2O3, uranyl nitrate (reads on fissionable isotope), and weighted according to stoichiometric formula; chemicals were mixed in a required ratio and ball milled), and
ball milling in a solvent for 24 hours, which reads on the claimed step (b) grinding the powder mixture to form a first milled powder.
Gong fails to disclose the steps of:
(c) calcinating the first milled powder at around 1100C so that a yttrium garnet phase is formed, thereby forming a calcinated powder, and
(d) grinding the calcinated powder to form a second milled powder including performing a second ball milling process.
Chang teaches performing a powder calcining step at 1100C prior to sintering, wherein the calcining step may be repeated up to three times, in order to completely form the YAG phase as a powder, thereby allowing the formation a final, dense YAG phase product which can advantageously be sintered at a lower sintering temperature with improved yield (para. [0065], calcining is repeated, up to three times; para. [0056], calcining at 1100-1650C to form a YAG phase; para. [0019], previous solid state methods require high sintering temperatures, 1600C or greater, to achieve high density articles (Gong teaches 1900C); para. [0023], YAG phase powder sinters to a higher density at a lower sintering temperature; para. [0035], providing complete YAG phase formation in calcining process; para. [0072], sintering temperatures as low as 1500C; para. [0096], wherein repeated calcining produces complete YAG phase transformation, whereas one calcination step is insufficient). Chang teaches that calcining at lower temperatures avoids sintering, and one of ordinary skill in the art would appreciate calcining at the low end of the range taught by Chang (1100C), in order fully avoid sintering of the powder prior to intended final sintering and densification (para. [0056]).
Chang teaches wherein the repeated calcining cycle includes ball milling, spray drying, compacting and calcining at 1100C (para. [0065], calcining is repeated…the repeated cycles may include…ball milling, spray drying, and compacting in each repeated cycle). Chang also teaches that the calcining cycles are followed by a final milling (automilling), drying, shaping and sintering to final article, and wherein a organics burnout cycle may be included (Fig. 1, steps 160 and 170; para. [0066], finished calcined powder subjected to final milling, drying, compacting and sintering; para. [0092], dried powder is uniaxial pressed and sintered; para. [0064], the organic burnout cycle equates to the 800C calcining cycle of Gong which removes organism (organics)).
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 the calcining steps of Chang, including repeating a calcining cycle up to three times, wherein the calcining cycle comprises ball milling, drying, compacting and calcinating at 1100C, and wherein the calcining steps are performed prior to shaping and sintering, as taught by Chang, for the invention disclosed by Gong. One would be motivated to do this in order to ensure and maximize the transformation of the YAG phase in the powder, thereby allowing for reduced sintering temperatures for dense products and increased yields (see teachings by Chang above). Further, one would also be motivated to specifically calcine the powder at 1100C in order to avoid unwanted sintering prior to final densification (see teachings by Chang above).
One of ordinary skill in the art would appreciate that Gong forms the YAG phase insitu during sintering (the calcining step described by Gong is for organic material burn off) which limits the control and amount of the YAG phase formed. Therefore, one of ordinary skill in the art would recognize that the teachings of Chang also allow for improved control and maximized YAG phase formation in the final product in addition to forming higher density articles at reduced sintering temperatures (see teachings by Chang above).
The invention according to Gong in view of Chang, for example, includes performing calcining and repeating the calcining cycle, wherein the calcining cycle includes ball milling, drying and compacting, and therefore would include the following steps: powder mixing, (first) ball milling, drying (or spray drying), compacting, first calcining, second calcining cycle (i.e., (second) ball milling, spray drying, compacting, second calcining), final automilling, drying, compacting, and sintering at a temperature lower than Gong (1500-1800C vs 1900C). Thus, the invention of Gong in view of Chang read on the claimed steps requiring (c) calcinating the first milled powder at around 1100C so that a yttrium garnet phase is formed, thereby forming a calcinated powder, and (d) grinding the calcinated powder to form a second milled powder including performing a second ball milling process.
Gong further discloses forming a compact, heating to remove organisms (organics), and further pressing the compact using CIP and sintering, which reads on claimed step of (e) shaping to form a shaped material portion and (f) sintering the shaped material portion (Section 2, experimental procedure; uranyl nitrate reads on fissionable isotope; see also Chang, para. [0092]).
While Gong does not disclose forming a plurality of shaped material portions as claimed (see steps e-f), such a modification would amount to a mere duplication of parts, and it has been held that a duplication of the essential working parts involves only routine skill in the art (see MPEP 2144.04.VI.B). One would be motivated to shape and sinter a plurality of shaped material portions in order to mass produce the sintered bodies.
Gong in view of Chang therefore teach the claimed limitations of steps (a)-(f).
Regarding Claim 17, Gong discloses ball milling in a solvent for 24 hours followed by drying in an oven, which would occur prior to calcination steps taught by Chang (see Claim 15 teachings above) (Gong, Experimental procedure; see also para. [0086]-[0088] of Chang, wherein powder is dried prior to forming the compact for calcining as well).
Regarding Claim 19, Chang discloses wherein shaping the second milled powder includes activating a hydraulic press, wherein the plurality of shaped material portions form one or more cylinders or pellets of the second milled powder (para. [0051]-[0052], uniaxial pressing with hydramet, which is a hydraulic press; grinding media shapes would be a cylinder or pellet; para. [0092], shaping with the uniaxial press prior to sintering; see Claim 15 above wherein it would be obvious to manufacture a plurality of compacts).
Regarding Claim 20, Gong discloses a method for fabricating U-doped YAG material comprising:
mixing solid alumina, yttria and uranyl nitrate in stoichiometric amounts, which reads on claimed step (a) of preparing a powder mixture by combining solid yttria powder, alumina powder, and the fissionable isotope in stoichiometric ratios (Experimental procedure, Al2O3, Y2O3, uranyl nitrate (reads on fissionable isotope), and weighted according to stoichiometric formula; chemicals were mixed in a required ratio and ball milled), and
ball milling in a solvent for 24 hours, which reads on the claimed step (b) grinding the powder mixture to form a first milled powder.
Gong fails to disclose the steps of:
(c) calcinating the first milled powder at around 1100C so that a yttrium garnet phase is formed, thereby forming a calcinated powder, and
(d) grinding the calcinated powder to form a second milled powder including performing a second ball milling process.
Gong further fails to disclose the claimed limitations (i)-(iii) om step (c) wherein the first milled powder is heated from room temperature to around 1100C, held for 5 hours and then cooled to room temperature.
Chang teaches performing a powder calcining step at 1100C prior to sintering, wherein the calcining step may be repeated up to three times, in order to completely form the YAG phase as a powder, thereby allowing the formation a final, dense YAG phase product which can advantageously be sintered at a lower sintering temperature with improved yield (para. [0065], calcining is repeated, up to three times; para. [0056], calcining at 1100-1650C to form a YAG phase; para. [0019], previous solid state methods require high sintering temperatures, 1600C or greater, to achieve high density articles (Gong teaches 1900C); para. [0023], YAG phase powder sinters to a higher density at a lower sintering temperature; para. [0035], providing complete YAG phase formation in calcining process; para. [0072], sintering temperatures as low as 1500C; para. [0096], wherein repeated calcining produces complete YAG phase transformation, whereas one calcination step is insufficient).
Chang teaches that calcining at lower temperatures avoids sintering, and one of ordinary skill in the art would appreciate calcining at the low end of the range taught by Chang (1100C), in order fully avoid sintering of the powder prior to intended final sintering and densification (para. [0056]). Further, one of ordinary skill in the art would appreciate that ball milling and handling of the powders before and after calcining occurs at room temperature (Chang does not disclose heating for ball milling and/or compacting), and therefore the powders would necessarily be heated from room temperature to the calcining temperature and cooled to room temperature from the calcining temperature.
Chang teaches wherein the repeated calcining cycle includes ball milling, spray drying, compacting and calcining at 1100C (para. [0065], calcining is repeated…the repeated cycles may include…ball milling, spray drying, and compacting in each repeated cycle). Chang also teaches that the calcining cycles are followed by a final milling (automilling), drying, shaping and sintering to final article, and wherein a organics burnout cycle may be included (Fig. 1, steps 160 and 170; para. [0066], finished calcined powder subjected to final milling, drying, compacting and sintering; para. [0092], dried powder is uniaxial pressed and sintered; para. [0064], the organic burnout cycle equates to the 800C calcining cycle of Gong which removes organism (organics)).
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 the calcining steps of Chang, wherein calcining includes heating from room temperature to 1100C, holding at 1100C for 2-64 hours and then cooling to room temperature, and the calcining steps of Change include repeating a calcining cycle up to three times, wherein the calcining cycle comprises ball milling, drying, compacting and calcining, and wherein the calcining steps are performed prior to shaping and sintering, as taught by Chang, for the invention disclosed by Gong. One would be motivated to do this in order to ensure and maximize the transformation of the YAG phase in the powder, thereby allowing for reduced sintering temperatures for dense products and increased yields (see teachings by Chang above). Further, one would also be motivated to specifically calcine the powder at 1100C in order to avoid unwanted sintering prior to final densification (see teachings by Chang above).
One of ordinary skill in the art would appreciate that Gong forms the YAG phase insitu during sintering (the calcining step described by Gong is for organic material burn off) which limits the control and amount of the YAG phase formed. Therefore, one of ordinary skill in the art would recognize that the teachings of Chang also allow for improved control and maximized YAG phase formation in the final product in addition to forming higher density articles at reduced sintering temperatures (see teachings by Chang above).
The invention according to Gong in view of Chang, for example, includes performing calcining by heating from room temperature to 1100C, holding at 1100C for 2-64 hours and then cooling to room temperature, and further repeating the calcining cycle, wherein the calcining cycle includes ball milling, drying, compacting and calcining, and therefore would include the following steps: powder mixing, (first) ball milling, drying (or spray drying), compacting, first calcining by heating from room temperature to 1100C for 2-64 hours and cooling to room temperature, second calcining cycle (i.e., (second) ball milling, spray drying, compacting, second calcining), final automilling, drying, compacting, and sintering at a temperature lower than Gong (1500-1800C vs 1900C). Thus, the invention of Gong in view of Chang read on the claimed steps requiring (c) calcinating the first milled powder at around 1100C so that a yttrium garnet phase is formed, thereby forming a calcinated powder, wherein calcinating the first milled powder in includes (i-iii) heating to 1100C from room temperature for at least 5 hours and cooling to room temperature, and (d) grinding the calcinated powder to form a second milled powder including performing a second ball milling process.
Gong further discloses forming a compact, heating to remove organisms (organics), and further pressing the compact using CIP and sintering, which reads on claimed step of (e) shaping to form a shaped material portion and (f) sintering the shaped material portion (Section 2, experimental procedure; uranyl nitrate reads on fissionable isotope; see also Chang, para. [0092]).
While Gong does not disclose forming a plurality of shaped material portions as claimed (see steps e-f), such a modification would amount to a mere duplication of parts, and it has been held that a duplication of the essential working parts involves only routine skill in the art (see MPEP 2144.04.VI.B). One would be motivated to shape and sinter a plurality of shaped material portions in order to mass produce the sintered bodies.
Gong in view of Chang therefore teach the claimed limitations of steps (a)-(f), including the calcinating steps (i)-(iii) of step (c).
Claim 8 and Claim 18 are rejected under 35 U.S.C. 103 as being unpatentable over Gong (previously cited and cited by Applicant in IDS filed July ,17, 2025, “Synthesis and characterization of structural and optical properties of Ce, U codoped YAG transparent ceramics”) in view of Chang (previously cited, US 20220242793 A1), as applied to Claim 1 and Claim 15 above, respectively, in further view of Mohammadi (previously cited, “The effects of ball milling time on the rheological, optical, and microstructural properties of YAG transparent ceramics”)
Regarding Claim 8 and Claim 18, Gong discloses wherein drying the first milled powder includes placing the first milled powder into an oven and heating the first milled powder in the furnace at 55C for 20 hours (Section 2, experimental procedure; oven reads on the broadest most reasonable interpretation of furnace), which reads on the claimed step of (i) placing the first milled powder into a furnace.
However, Gong does not disclose wherein heating in the furnace (oven) is at approximately 110C for at least 24 hours as claimed.
Mohammadi teaches wherein drying a slurry of yttria and alumina powders, which have been ball milled for various milling times, suitably is performed in an oven at 110C for 24 hours (Pg. 1120, Experimental, “drying of the samples in an oven at 110C for 24 hours”).
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 a drying temperature of 110C and a drying time of 24 hours, as taught by Mohammadi, for the invention disclosed by Gong and Chang, because Mohammadi demonstrates that these parameters are suitable for drying slurries which have been milled for a range of milling times and comprise a range of particle sizes as a result of the milling (see teaching above). Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. “[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation.” See MPEP 2144.05.II.
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Gong (previously cited and cited by Applicant in IDS filed July ,17, 2025, “Synthesis and characterization of structural and optical properties of Ce, U codoped YAG transparent ceramics”) in view of Chang (previously cited, US 20220242793 A1), as applied to Claim 1 above, in further view of Lee (previously cited, US 20040109808 A1).
Regarding Claim 13, Gong discloses using a tungsten heating element vacuum furnace for sintering (section 2, Experimental procedure), but does not disclose using an alumina tube furnace as claimed.
Lee teaches wherein compacts with YAG powder and doped YAG powder may be suitably sintered in an alumina tube furnace (para. [0025]).
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 alumina tube furnace, as taught by Lee, for the invention disclosed by Gong and Chang, because this furnace is suitable for sintering a compact of YAG powder (see teaching above).
Response to Arguments
Applicant's arguments, filed May 19, 2026, have been fully considered but are respectfully not found persuasive.
Regarding Chang:
Applicant argues that Chang expressly describes milling the calcined YAG compact without grinding media and therefore does not disclose a second ball milling process.
Applicant argues that the teaching of Chang would require autonomous milling (without media) of the calcined compact.
Applicant argues the instant invention requires ball milling as important for the calcined product in order to break apart the agglomerates, which affects transparency after sintering.
Applicant argues there is not sufficient rationale for modifying Gong with Chang to perform a second ball milling process because Chang teaches wherein post-calcination milling is without grinding media.
These arguments are not found persuasive.
Chang discloses calcining the powder to form the YAG phase, and further wherein calcination is repeated in order complete YAG phase formation in the powder (para. [0065]; para. [0096]). Chang teaches wherein the calcination cycle includes ball milling, compacting and calcining (para. [0065], “For repeated calcining, the repeated cycles may include any or all of the steps of adding silica, ball milling, spray drying, and compacting in each repeated cycle"). Thus, in order to repeat calcination, the powder would be ball milled a second time. The autonomous milling argued by Applicant is applied after the calcination cycles in Chang.
Further, the calcination teachings of Chang are applicable to Gong because Chang teaches this method enables lower sintering temperatures (1500-1800C). A sintering temperature of 1500C, for example, is well below the sintering temperature disclosed by Gong (1900C).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Walker (US 20240391836 A1): teaches a Zr-doped yttrium aluminum garnet method including grinding, drying, calcinating to form the YAG phase, shaping and sintering (para. [0130]; para. [0134]; para. [0137]-[0140]; para. [0150]-[0151]).
Walker further teaches wherein the calcinated powder mixture may be subjected to the milling process (see above wet ball milling and drying process) to tailor particle size distributions (para. [0143]). One of ordinary skill in the art would appreciate the method outlined by Walker is the SSR process.
Pan (US 20110210658 A): teaches wherein the solid state reaction (SSR) process may be used to create cerium-doped YAG powder (para. [0055]; para. [0069]; para. [0106]-[0107]).
Gong (applied above, further teachings, “Synthesis and characterization of structural and optical properties of Ce, U codoped YAG transparent ceramics”): teaches a uranium-doped and a uranium-cerium co-doped YAG ceramic in order to provide a material which is more suitable for neutron detection without γ-ray interference (Abstract: Introduction, para. 1).
Lee (applied above, further teachings, US 20040109808 A1): teaches manufacturing doped YAG powder by the co-precipitation method, deagglomerating the YAG powder by milling and drying both prior to and following calcination at low temperature and before calcination at high temperature (para. [0008]; para. [0011]-[0013]; para. [0018]; para. [0020]). Lee teaches wherein the YAG powder may be subjected to further powder processing by ball milling in order to aid in engineering the surface of the particle to achieve uniform particle packing and appropriate green strength (para. [0021]).
Lee further teaches wherein a plurality of compacts are shaped and sintered (para. [0024]-[0025], compacts).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CATHERINE P SMITH whose telephone number is (303)297-4428. The examiner can normally be reached Monday - Friday 9:00-4:00 MT.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith Walker can be reached at (571)-272-3458. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
CATHERINE P. SMITH
Patent Examiner
Art Unit 1735
/CATHERINE P SMITH/Examiner, Art Unit 1735
/KEITH WALKER/Supervisory Patent Examiner, Art Unit 1735
Prosecution Insights