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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 19 February, 2026 has been entered.
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.
Claims 1-4, 8 and 11-12 are rejected under 35 U.S.C. 103 as being unpatentable over Tajima (US 2021/0169747, previously presented) in view of Matsuyuki (2017/0066108), Mase (US 2018/0333238, previously presented), and Izezaki (5,895,313).
Regarding claim 1, Tajima teaches A surface treatment method for dental zirconia ([Abstract]), comprising:
(a) performing a polishing on the surface of zirconia ([0075&0079]), wherein the zirconia comprises tetragonal and cubic zirconia with less than 15% monoclinic phase ([0018] describes the zirconia having very little monoclinic crystals less than 5%), 95%vol or more of all particles of which have an average diameter of 100 to 1200nm ([0018] teaches a 95% vol), and which has a density of 99.5% or more of the theoretical density and is opalescent ([0020] describes the zirconia having an improved transparency (opalescent) due to the lack of monoclinic crystals, examiner further notes the claim limitation seems to be a recitation of the properties of the zirconia); and
(b) sandblasting the polished surface ([0077]) with alumina particles ([0077] describes sandblasting the surface with alumina particles), wherein the sandblasting in step (b) is performed by selecting a particle size of the alumina particles according to a zirconia composition ([0077] describes selecting alumina particles of a specific size for a zirconia to prepare the zirconia);
wherein the zirconia is selected from the group consisting of:
(i) 3Y-TZP, wherein the average particle size of the alumina particles is 100 to 120 um;
(ii) 4Y-PSZ, wherein the average particle size of the alumina particles is 80 to 100 um; and
(iii)5Y-PSZ (([0020] teaches the zirconia is 2-8 mol% including 5 mol% (5Y-PSZ)), wherein the average particle size of the alumina particles is 50 um ([0077] teaches the alumina particles to be 50um).
Tajima teaches the abrasive blasting is applied to the zirconia surface to create a matte surface ([0077]). Tajima fails to explicitly teach sandblasting using the alumina particles of a particular size so to control an extent of a tetragonal-to-monoclinic phase transformation induced on the surface of the zirconia, thereby generating and controlling residual compressive stress on the surface of the zirconia. Matsuyuki teaches blasting a surface of zirconia and can be considered analogous art because it is within the same field of endeavor. Matsuyuki teaches the concept of using abrasive blasting on zirconia to control an extent of a tetragonal-to-monoclinic phase transformation induced on the surface of the zirconia ([0066] describes using blasting to transform from a tetragonal to monoclinic phase transformation on the surface structure), thereby generating and controlling residual compressive stress on the surface of the zirconia ([0066] describes the transformation due to blasting to control residual compressive stress and increase fracture toughness of the surface). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date to have using the alumina particles of a particular size, as taught by Tajima, so to control an extent of a tetragonal-to-monoclinic phase transformation induced on the surface of the zirconia, thereby generating and controlling residual compressive stress on the surface of the zirconia, as taught by Matsuyuki, since such a modification of using blasting on a surface of zirconia yields the predictable result of a matte surface and to increase fracture toughness of the surface ([0066]).
Tajima as modified fails to explicitly teach sandblasting the polished surface using a nozzle-equipped sandblasting apparatus. Mase teaches the abrasive blasting to surface treat a dental zirconia and can be considered analogous art because it is within the same field of endeavor. Mase teaches a nozzle-equipped sandblasting apparatus (Ref. 20, Fig. 3). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date to have a nozzle-equipped sandblasting apparatus, as taught by Mase, be using in the sandblasting method, as taught by Tajima as modified, because it is old and well known in the art that sandblasting is performed with an apparatus with a nozzle to produce the predictable result of controlling the flow of abrasive during blasting.
Tajima as modified fails to explicitly teach 5Y-PSZ wherein the average particle size of the alumina particles is 10 to 25 um. Izezaki teaches an abrasive blasting system through a nozzle using alumina particles and can be considered analogous art because it is within the same field of endeavor. Izezaki teaches alumina particles in blasting can have a size range from 1 to 100 um to prevent the nozzle from jamming ([Col. 5, Lines 61-68 & Col. 6, Lines 1-7]). Given the suggestion of Izezaki, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the particle size since it has been held that “where the only difference between the prior art and the claims was a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device was not patentably distinct from the prior art device” Gardner v. TEC Syst., Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 SPQ 232 (1984). In the instant case, the particle size would not operate differently with the claimed particle size of 10 to 25 um and since the alumina particle size of Tajima has a 5Y-PSZ particle size the device would function appropriately having the claimed particle size by abrading a surface through a nozzle. Further, it appears that applicant places no criticality on the range claimed, indicating simply that the particle size “may” be 10 to 50 um within the claimed ranges (specification pp. [pg. 7, Lines 16-17]).
Regarding claim 2, Tajima as modified teaches the limitations of claim 1, as described above, and Tajima, as best understood, further teaches wherein the zirconia in (a) is any one selected from the group consisting of 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP), 4 mol% partially stabilized zirconia (4Y-PSZ), and 5 mol% partially stabilized zirconia (5Y-PSZ) ([0020] teaches the 2- to 8 mol %).
Regarding claim 3, Tajima as modified teaches the limitations of claim 1, as described above, and Mas has incorporated the sandblaster into claim 1. Given the sandblaster, of Mas, has been incorporated in claim 1, Tajima as modified further teaches the vertical distance between the nozzle-equipped sandblasting apparatus and the polished surface is 1 to 100 mm ([Table-1] describes the ejection distance is 20mm). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date to have a nozzle-equipped sandblasting apparatus, as taught by Mase, be using in the sandblasting method, as taught by Tajima, because it is old and well known in the art that sandblasting is performed with an apparatus with a nozzle to produce the predictable result of controlling the flow of abrasive during blasting.
Regarding claim 4, Tajima as modified teaches the limitations of claim 1, as described above, and Tajima further teaches wherein, in (b), the pressure for sandblasting with alumina particles is 0.1 to 0.5 Mpa ([0077] describes blasting with 0.2 MPa of pressure).
Regarding Claim 8, Tajima as modified teaches the limitations of claim 1, as described above, and Tajima teaches a polishing and sandblasting steps as part of the surface treatment method, see claim 1 above. Tajima further teaches a spectral analysis of the zirconia to give some kind of topographical wavelength ([0033], examiner notes spectral analysis gives a frequency and wavelength of the zirconia). Examiner interprets the claim to be in regards to a purported merit when performing or not performing the polishing and sandblasting step, therefore, it would have been obvious wherein a target peak of the zirconia at 147 cm-1 shifts to a higher wavenumber as a result of sandblasting would have been obvious to one of ordinary skill in the art.
Regarding Claim 11, Tajima as modified teaches the limitations of claim 1, as described above, and Tajima teaches a polishing and sandblasting steps as part of the surface treatment method, see claim 1 above. Tajima further teaches sandblasting changes the surface topography of the zirconia ([0003]) and measurement and monitoring of the zirconia ([0033]). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date to surface treat zirconia to causes a bigger change in surface topography than when surface treatment is not performed, as a person with ordinary skill has good reason to pursue the known options within his or her technical grasp. In turn, because the residual stress as claimed is a property result of the surface treatment predicted by the prior art, it would have been obvious to causes a bigger change in surface topography than when surface treatment is not performed. If this lead to the anticipated success, it is likely the product of not innovation but ordinary skill and common sense.
Regarding Claim 12, Tajima teaches A dental article comprising dental zirconia ([Abstract] describes a dental product made of zirconia, note examiner interprets a dental article as any product used for dentistry) made by the surface treatment method of claim 1 (See rejection of claim 1 method of surface treatment above.)
Claims 9 is rejected under 35 U.S.C. 103 as being unpatentable over Tajima as modified as applied to claim 1 above, and further in view of Hinrichs (NPL, “Analysis of alumina powders”)
Regarding Claim 9, Tajima as modified teaches the limitations of claim 1, as described above, and fails to explicitly teach wherein the trace elements of the alumina particles comprise Si, Fe and Zr. However, given the teachings of Hinrichs, it is old and well known in the art alumina particles contain trace elements including Si, Fe, and Zr (Table 2). Therefore, given the base of the surface treatment method consists of Zr, it would have been obvious to one of ordinary skill in the art before the effective filing date to have wherein the trace elements of the alumina particles comprise Si, Fe and Zr, because it is old and well known in the art that alumina particles contain multiple trace elements and is a property of the alumina particles.
Response to Arguments
Applicant’s amendments to the claims are acknowledged and examiner has withdrawn the 35 USC 112(d) and 35 USC 112(b) rejection.
Applicant's arguments filed 19 February, 2026 have been fully considered but they are not persuasive.
Regarding Claim 1, Applicant has amended the claim thereby necessitating a new grounds of rejection and reinterpretation of prior art. In response to applicant's argument that there is a lack of advantageous results with carrying out the claimed method, the test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981).
Applicant’s arguments that Tajima in view of Mase fails to teach the new limitations of choosing different alumina particle sizes based upon the type of zirconia to control a tetragonal to monoclinic phase transformation and residual compressive stress on the surface of the zirconia has been fully considered and is not persuasive. Examiner has applied Tajima in view of Matsuyuki and Mase has been applied to the 35 USC 103 rejection above. Tajima teaches sandblasting the polished surface ([0077]) with alumina particles ([0077] describes sandblasting the surface with alumina particles), wherein the sandblasting in step (b) is performed by selecting a particle size of the alumina particles according to a zirconia composition ([0077] describes selecting alumina particles of a specific size for a zirconia to prepare the zirconia). Examiner notes that there is some selection of the alumina particles described due to being at a specific pressure and to achieve the specific result of preparing the zirconia surface to be matte. Matsuyuki teaches the concept of using abrasive blasting on zirconia to control an extent of a tetragonal-to-monoclinic phase transformation induced on the surface of the zirconia ([0066] describes using blasting to transform from a tetragonal to monoclinic phase transformation on the surface structure), thereby generating and controlling residual compressive stress on the surface of the zirconia ([0066] describes the transformation due to blasting to control residual compressive stress and increase fracture toughness of the surface). Therefore, given both Masayuki and Tajima teach blasting a zirconia surface to make a matte surface, it would have been obvious to one of ordinary skill in the art before the effective filing date to have using the alumina particles of a particular size, as taught by Tajima, so to control an extent of a tetragonal-to-monoclinic phase transformation induced on the surface of the zirconia, thereby generating and controlling residual compressive stress on the surface of the zirconia, as taught by Matsuyuki, since such a modification of using blasting on a surface of zirconia yields the predictable result of a matte surface and to increase fracture toughness of the surface ([0066]).
Applicant’s amendments to the claim in regards to the alumina particle sizes have changed the scope of the claim necessitating a new grounds of rejection. Examiner has applied Izezaki to the 35 USC 103 rejection above. Izezaki teaches alumina particles in blasting can have a size range from 1 to 100 um to prevent the nozzle from jamming ([Col. 5, Lines 61-68 & Col. 6, Lines 1-7]). Given the suggestion of Izezaki, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the particle size since it has been held that “where the only difference between the prior art and the claims was a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device was not patentably distinct from the prior art device” Gardner v. TEC Syst., Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 SPQ 232 (1984). In the instant case, the particle size would not operate differently with the claimed particle size of 10 to 25 um and since the alumina particle size of Tajima has a 5Y-PSZ particle size the device would function appropriately having the claimed particle size by abrading a surface through a nozzle. Further, it appears that applicant places no criticality on the range claimed, indicating simply that the particle size “may” be 10 to 50 um within the claimed ranges (specification pp. [pg. 7, Lines 16-17]).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's
disclosure. Rolf (8,309,015), Knapp (8,298,329), Brodkin (2010/0133711), and Rosenflanz
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/DANA LEE POON/Examiner, Art Unit 3723