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 .
Response to Amendment
The reply filed on September 22, 2025 has been entered into the prosecution for the application. Currently, claims 1-8 are pending. Claims 5 and 6 are withdrawn. Claims 1, 4, and 8 have been amended.
The prior rejection of claims 4 and 8 under 35 U.S.C. 112(b) is withdrawn as moot in view of the amendments to those claims.
The prior art grounds of rejection of claims 1-3 and 7 are maintained.
The prior art grounds of rejection of claims 4 and 8 are withdrawn.
Applicant’s amendments necessitated the new ground(s) of rejection.
Claim Rejections - 35 USC § 103
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 (i.e., changing from AIA to pre-AIA ) 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 text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1 and 3-4 are rejected under 35 U.S.C. 103 as being unpatentable over WO 2012133466 A1 to Fujimoto et al. (with reference to the previously provided machine translation, hereinafter “Fujimoto”).
Regarding claim 1, Fujimoto teaches a glass sheet (¶ 0021) comprising 50-70 mass% SiO2 (¶ 0017). Fujimoto teaches that the process for manufacturing the glass sheet comprises a melting step during which the raw materials are melted at a temperature of 1550°C or higher (¶ 0023); a fining step (¶ 0024); a stirring step during which the molten glass is stirred at a temperature of 1440°C to 1500°C (¶ 0025); and a supplying step (¶ 0026). This manufacturing process is substantially identical to the glass sheet manufacturing process of the claimed invention (see Specification at p. 14, ¶ 0040, describing a melting step at a temperature of 1530°C to 1680°C; ¶ 0041, describing a fining step; ¶ 0042, describing a stirring step during which the molten glass is stirred at a temperature of preferably 1500°C or less, more preferably 1450°C or less; ¶ 0044, describing a supplying step). Given that the glass sheet of Fujimoto and the glass sheet of the claimed invention are both high-SiO2 content glass sheets produced by substantially identical processes, and given in particular the importance of the process temperature of the stirring step to the amount of CO2 gas released from the glass sheet (see the Specification of the present application at p. 15, ¶ 0043), of one of ordinary skill in the art would reasonably expect that the glass sheet of Fujimoto and the glass sheet of the claimed invention would inherently exhibit substantially identical properties, including releasing CO2 gas in an amount of 2.0 μL/g or less when the glass sheet is subjected to heat treatment under the conditions of 1,500°C and 4 hours after having been subjected to preheating under the conditions of 900°C and 1 hour. 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 obviousness has been established (see MPEP 2112.01(I), first paragraph).
Regarding claim 3, Fujimoto does not disclose a precise temperature at 102.5 dPa∙s for the glass sheet. However, given that the glass sheet of Fujimoto and the glass sheet of the claimed invention are both high-SiO2 content glass sheets produced by substantially identical processes, one of ordinary skill in the art would reasonably expect that the glass sheet of Fujimoto and the glass sheet of the claimed invention would inherently exhibit substantially identical properties, including a temperature at 102.5 dPa∙s of from 1530°C to 1680°C. 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 obviousness has been established (see MPEP 2112.01(I), first paragraph). Moreover, Fujimoto does disclose that the glass sheet has a temperature of 1440°C at 121 Pa∙s (i.e., approx. 103.08 dPa∙s) and a temperature of 1500°C at 60 Pa∙s (i.e., approx. 102.78 dPa∙s) (¶ 0025). Given that the viscosity of a glass material is inversely related to temperature, one of ordinary skill in the art would reasonably expect, based on the known viscosity data points disclosed by Fujimoto, that the glass sheet temperature at 102.5 dPa∙s (approx.. 31.6 Pa∙s) would fall within the range of 1530°C to 1680°C.
Regarding claim 4, Fujimoto teaches a display comprising a substrate wherein the substrate is the glass sheet according to claim 1 and wherein the display is a liquid crystal display (¶ 0016).
Claim(s) 2 and 7-8 are rejected under 35 U.S.C. 103 as being unpatentable over Fujimoto or, alternatively, over Fujimoto in view of CN 103168010 A to Kimijima et al. (with reference to the previously provided machine translation, hereinafter “Kimijima”).
Regarding claim 2, Fujimoto teaches the glass sheet according to claim 1 (as set forth above) and teaches wherein the glass sheet comprises as a glass composition, in terms of the following oxides in mass%, 50% to 70% SiO2, 10% to 25% Al2O3, 5% to 18% B2O3, 0% to 10% MgO, 0% to 20% CaO, 0% to 20% SrO, and 0% to 10% of BaO (¶ 0017). Thus, for those listed oxides, Fujimoto teaches mass percentage compositional proportion ranges that overlap or lie within the recited ranges of claim 2. In a case where claimed ranges “overlap or lie inside ranges disclosed by the prior art,” a prima facie case of obviousness exists (see MPEP 2144.05).
Fujimoto teaches that the glass sheet comprises more than 0.10 mass% and not more than 2.0 mass% R’2O, where R’2O is one or more of Li2O, Na2O, and K2O (all alkali metal oxides) (¶ 0017). The lower end of this range is very close to being “substantially free” of an alkali metal oxide, as the written description of the present application defines the term “substantially free” as “0.1% or less” in terms of mass% (see Specification at ¶ 0032). A prima facie case of obviousness exists where the claimed ranges or amounts do not overlap but are merely close (see MPEP 2144.05(I), second paragraph).
Alternatively, Kimijima, in the same field of endeavor, teaches a glass sheet (Abstract) comprising (in terms of mass%) 50% to 70% SiO2, 10% to 25% Al2O3, 5% to 18% B2O3, 0% to 10% MgO, 0% to 20% CaO, 0% to 20% SrO, and 0% to 10% of BaO (¶ 0030, claim 6). Kimijima teaches that, when the glass sheet is to be used as a glass substrate for a liquid crystal display or an OLED display, it is preferable that R’2O is not contained substantially, R’2O being one or more of Li2O, Na2O, and K2O (¶ 0109; see also ¶ 0029, setting a lower limit of 0 mass% for R’2O).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the glass sheet of Fujimoto by lowering the content of alkali metal oxides Li2O, Na2O, and K2O to zero, as taught by Kimijima, thereby producing a glass sheet substantially free of an alkali metal oxide. One of ordinary skill in the art would have been motivated to do so by a desire to produce a glass sheet suitable for use as a glass substrate for a liquid crystal display (Kimijima at ¶ 0109).
Regarding claim 7, Fujimoto or, alternatively, Fujimoto as modified by Kimijima teaches the glass sheet according to claim 2. Given that the glass sheet of the prior art and the glass sheet of the claimed invention are both high-SiO2 content glass sheets produced by substantially identical processes, one of ordinary skill in the art would reasonably expect that the glass sheet of Fujimoto (or Fujimoto as modified by Kimijima) and the glass sheet of the claimed invention would inherently exhibit substantially identical properties, including a temperature at 102.5 dPa∙s of from 1530°C to 1680°C. 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 obviousness has been established (see MPEP 2112.01(I), first paragraph). Moreover, Fujimoto does disclose that the glass sheet has a temperature of 1440°C at 121 Pa∙s (i.e., approx. 103.08 dPa∙s) and a temperature of 1500°C at 60 Pa∙s (i.e., approx. 102.78 dPa∙s) (¶ 0025). Given that the viscosity of a glass material is inversely related to temperature, one of ordinary skill in the art would reasonably expect, based on the known viscosity data points disclosed by Fujimoto, that the glass sheet temperature at 102.5 dPa∙s (approx.. 31.6 Pa∙s) would fall within the range of 1530°C to 1680°C. Further, Kimijima teaches that the glass sheet has a temperature at 102.5 dPa∙s of from 1550°C to 1680°C, further bolstering the prima facie case.
Regarding claim 8, Fujimoto or, alternatively, Fujimoto as modified by Kimijima teaches a display comprising a substrate wherein the substrate is the glass sheet according to claim 2 and wherein the display is a liquid crystal display (see Fujimoto at ¶ 0016; Kimijima at ¶ 0109).
Response to Arguments
Applicant’s arguments filed September 22, 2025 have been fully considered but they are not persuasive.
In the Remarks submitted with the reply filed September 22, 2025 (hereinafter “Remarks”), Applicant states:
Claim 1 limits the amount of CO2 gas released to 2.0 μL/g or less when the glass sheet is subjected to heat treatment under the conditions of 1,500°C for 4 hours after having been subjected to preheating under the conditions of 900 °C for 1 hour.
This regulation is instrumental in reducing the number of bubbles caused by the stirring reboil. For example, in the Example (Sample No. 1) of Table 1 in paragraph [0058] of the originally filed specification of the present application, decompressed glass cullet (Glass A) was used as a glass raw material, and the stirring step was conducted at 1450 °C, thereby achieving a CO2 gas release amount of 1.6 μL/g under these conditions. (See also paragraphs [0051] and [0052] of the originally filed specification of the present application).
Fujimoto fails to disclose or suggest the above-noted features of claim 1.
(Remarks at p. 4.) This whole line of argument is unpersuasive. Fundamentally, claim 1 is a product claim that defines the product in terms of its physical performance characteristics when subjected to a heat treatment. Applicant is arguing as if claim 1 were a method claim or a product-by-process claim. Crucially, a prima facie case of obviousness is established 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 (see MPEP 2112.01(I), first paragraph). The Office having made a prima facie case of obviousness on the basis of substantially identical composition and substantially identical processes of manufacture (see above, p. 3), Applicant must rebut that prima facie case with evidence showing compositional differences such as would lead to different physical performance attributes during heat treatment. Applicant has not done that here. Evidence of structural difference is needed here, and arguments cannot take the place of factually supported objective evidence. See In re De Blauwe, 736 F.2d 699, 705, 222 USPQ 191, 196 (Fed. Cir. 1984); In re Schulze, 346 F.2d 600, 602, 145 USPQ 716, 718 (CCPA 1965); MPEP 2145.
Conclusion
THIS ACTION IS MADE FINAL. 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.
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/P.A.F./Examiner, Art Unit 1731
/JENNIFER A SMITH/Primary Patent Examiner, Art Unit 1731