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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 March 20, 2026, has been entered.
Election/Restrictions
Newly submitted claims 50-58 are directed to an invention that is independent or distinct from the invention originally claimed for the following reasons: the inventions of claims 50 and 54 lack unity because the prior art, Hu, teaches all of the corresponding technical feature that claims 30, 50 and 54 have in common by virtue of teaching all of the limitations of claim 30. Please note that claims 50 and 54 include a limitation to an intermediate layer that is not required by claim 30.
Since applicant has received an action on the merits for the originally presented invention, this invention has been constructively elected by original presentation for prosecution on the merits. Accordingly, claims 50-58 are withdrawn from consideration as being directed to a non-elected invention. See 37 CFR 1.142(b) and MPEP § 821.03.
To preserve a right to petition, the reply to this action must distinctly and specifically point out supposed errors in the restriction requirement. Otherwise, the election shall be treated as a final election without traverse. Traversal must be timely. Failure to timely traverse the requirement will result in the loss of right to petition under 37 CFR 1.144. If claims are subsequently added, applicant must indicate which of the subsequently added claims are readable upon the elected invention.
Should applicant traverse on the ground that the inventions are not patentably distinct, applicant should submit evidence or identify such evidence now of record showing the inventions to be obvious variants or clearly admit on the record that this is the case. In either instance, if the examiner finds one of the inventions unpatentable over the prior art, the evidence or admission may be used in a rejection under 35 U.S.C. 103 or pre-AIA 35 U.S.C. 103(a) of the other invention.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim 32 is rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. Claim 32 requires that the total depth is 50 microns. The disclosure does not include support for this limitation. Applicant’s as-filed spec includes a discussion of the CS at a depth of 50 microns (paragraph 0007), but does not include support for a total depth of the strengthened layers being 50 microns.
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 30-36, 38-42 are rejected under 35 U.S.C. 103 as being unpatentable over CN 111087174 Hu et al with evidence from US 2015/0044474 Beall et al.
Regarding claim 30, Hu teaches a chemically strengthened glass ceramic (paragraph 0015) comprising:
an inside;
a surface;
a first side;
a second side opposite to the first side (paragraph 0031 teaching use as a window, which is a sheet shape); and
strengthening layers respectively formed on the first side and the second side (paragraph 0024, where a “salt bath” immerses the entire product in the solution),
wherein the glass ceramic further comprise a glass phase and a crystal phase (paragraph 0067),
wherein the crystal phase comprises castorite and lithium disilicate (paragraph 0067, where castorite and pearlite are different names for the same compound),
wherein the glass ceramic comprises lithium oxide, silicon dioxide, sodium oxide, potassium oxide and aluminum oxide (paragraph 0013),
wherein the glass ceramic optionally comprises phosphorus pentoxide (paragraph 0013), zirconium dioxide (paragraph 0013), titanium dioxide (0%), magnesium oxide (paragraph 0013), calcium oxide (0%), zinc oxide (paragraph 0014), and boron trioxide (paragraph 0014), and
wherein the glass ceramic comprises the following compounds in mole percentage:
lithium oxide (Li2O): 18-30% (paragraph 0013);
silicon dioxide (SiO2): 55-70% (paragraph 0013);
sodium oxide (Na2O) + potassium oxide (K2O): 0.5-5% (paragraph 0013);
aluminum oxide (A12O3): 3-10% (paragraph 0013);
phosphorus pentoxide (P2O5) + zirconium dioxide (ZrO2) + titanium dioxide (TiO2): 1.5-11% (paragraph 0013);
magnesium oxide (MgO) + calcium oxide (CaO) + zinc oxide (ZnO): 0-10% (paragraph 0014); and
boron trioxide (B2O3): 0% to 5% (paragraph 0014).
“In the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists,” (MPEP 2144.05 Section I). Therefore, absent evidence of criticality, the taught ranges of the above elements reads on the claimed ranges.
Hu does not explicitly teach that the glass ceramic includes potassium oxide. However, Hu does teach that the glass is strengthened in a potassium salt bath (paragraph 0024). Beall teaches that when ion exchange strengthening is carried out, larger ions, such as potassium, replace smaller ions such as sodium (paragraph 0034). Therefore, in Hu, during ion exchange, potassium ions in the salt bath would replace some of the sodium ions, such that potassium oxide would also be present in the strengthened glass ceramic.
Regarding claim 31, Hu teaches that each of the strengthening layers comprises a potassium strengthening layer and a sodium strengthening layer located sequentially from the surface to the inside (paragraphs 0024-0029, where potassium must be closer to the surface because the ions are bigger and therefore would not travel as deep as sodium ions),
wherein t is a thickness of the chemically strengthened glass ceramic (0052, 1 mm thick), and
wherein a total depth of the strengthening layers is 140 microns (paragraph 0058).
Hu does not explicitly teach the first or second depths. However, as Hu satisfies all of the previous limitations, and Hu’s materials and method are indistinguishable from the claimed materials and method, it is reasonable to expect that Hu’s first depth and second depth would also be 0.01 to 5 microns, and 100 microns or more, respectively. “Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established” (MPEP 2112.01 Section I).
Regarding claim 32, Hu teaches that a total depth of the strengthening layers is 140 microns (paragraph 0058, where a depth beyond 50 microns is not excluded from the claim, and
Hu does not explicitly teach the compressive stress at the total depth. However, as Hu satisfies all of the previous limitations, and Hu’s materials and method are indistinguishable from the claimed materials and method, it is reasonable to expect that Hu’s compressive stress at the total depth would also be 50 MPa or more. “Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established” (MPEP 2112.01 Section I).
Regarding claims 33 and 34, Hu does not explicitly teach the average tensile stress or the sodium concentration gradient, but does teach a product thickness of 1 mm (paragraph 0052). Hu further teaches that sodium oxide (Na2O) + potassium oxide (K2O): 0.5-5% (paragraph 0013).
However, as Hu satisfies all of the previous limitations, and Hu’s materials and method are indistinguishable from the claimed materials and method, it is reasonable to expect that Hu’s average tensile stress would also be 35 to 85 MPa, and Hu’s sodium concentration would also decrease monotonically in a thickness range of 10 to 100 microns. “Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established” (MPEP 2112.01 Section I).
“In the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists,” (MPEP 2144.05 Section I). Therefore, absent evidence of criticality, the taught range of 0.5 to 5% Na2O+K2O reads on the claimed range of 3.5 to 4.5%.
Regarding claim 35, Hu does not explicitly teach the presence or absence of a sodium precipitate. However, because such a presence would be disclosed, the examiner is taking the position that Hu’s silence suggests that a sodium precipitate is not present.
Regarding claim 36, Hu teaches that
wherein an average transmittance of the chemically strengthened glass ceramic in an optical wavelength range of 400 nanometers (nm) to 700 nm is 89% (paragraph 0017, visible range), and
wherein a haze of the chemically strengthened glass ceramic is less than or equal to 0.3% (paragraph 0017).
Hu does not explicitly teach the La*b* color coordinates. However, Hu does teach use as windows in aircraft and the like (paragraph 0031). The b* coordinate of a colorless glass would be 0. It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to include clear, transparent, colorless glass for use in windows because color may alter the vision of those in the aircraft.
“In the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists,” (MPEP 2144.05 Section I). Therefore, absent evidence of criticality, the taught range of 0.3% haze or less reads on the claimed range of 0.25% haze or less.
Regarding claim 38, Hu does not explicitly teach the total mass content of the crystal phase. Hu does, however, teach that the crystallization ratio and crystal type affects the elastic modulus of the glass ceramic (paragraph 0031).
Since the instant specification is silent to unexpected results, the specific crystal content of the glass ceramic is not considered to confer patentability to the claims. As the physical and optical characteristics are variables that can be modified, among others, by adjusting the parameters of the method, the precise crystal content would have been considered a result effective variable by one having ordinary skill in the art before the effective filing date of the invention. As such, without showing unexpected results, the claimed crystal content cannot be considered critical. Accordingly, one of ordinary skill in the art, before the effective filing date of the invention, would have optimized, by routine experimentation, the crystal ratio and type in the glass ceramic to obtain the desired physical characteristic (In re Boesch, 617 F.2d. 272, 205 USPQ 215 (CCPA 1980)), since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223). See MPEP 2144.05 Section II.
Regarding claim 39, Hu teaches a three-dimensional (3D) chemically strengthened glass ceramic (paragraph 0002 teaching products).
Regarding claim 40, Hu teaches that the thickness of the chemically strengthened glass ceramic is 1 mm (paragraph 0052).
Regarding claim 41, Hu does not explicitly teach the process capability index. However, as Hu satisfies all of the previous limitations, and Hu’s materials and method are indistinguishable from the claimed materials and method, it is reasonable to expect that Hu’s process capability index (CPK) of a three-dimensional (3D) glass ceramic with a length tolerance and a width tolerance within +0.1 millimeters (mm) would also be greater than or equal to 0.8. “Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established” (MPEP 2112.01 Section I).
Regarding claim 42, Hu teaches that a Vickers hardness of the chemically strengthened glass ceramic is 700 kgf/mm2. Hu does not explicitly teach the impact resistance strength. However, as Hu satisfies all of the previous limitations, and Hu’s materials and method are indistinguishable from the claimed materials and method, it is reasonable to expect that Hu’s impact resistance strength of the chemically strengthened glass ceramic would also be greater than or equal to 0.07 joules. “Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established” (MPEP 2112.01 Section I).
Response to Arguments
Applicant's arguments filed March 9, 2026, have been fully considered but they are not persuasive. Applicant argues that Hu does not teach the claimed composition because potassium oxide is absent. However, as discussed above, with evidence from Beall, the ion exchange process provides the potassium oxide when potassium ions replace sodium ions.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Megha M Gaitonde whose telephone number is (571)270-3598. The examiner can normally be reached Monday-Friday 8:30 am to 5 pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Frank Vineis can be reached at 571-270-1547. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MEGHA M GAITONDE/Primary Examiner, Art Unit 1781
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