DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 November 3, 2025 has been entered.
Specification
The lengthy specification has not been checked to the extent necessary to determine the presence of all possible minor errors. Applicant’s cooperation is requested in correcting any errors of which applicant may become aware in the specification.
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, 7-10, 12, and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Garner et al. (2015/0044445) in view of Denry et al. (5,705,273). Garner teaches a method of chemically strengthening an amorphous glass-based article ([0030]) having a thickness in the range of 50 µm to 300 µm ([0032]), which overlaps within a range of about 20 µm to 300µm. Garner teaches strengthening can be performed by ion exchange processes using a molten salt bath, a solution, a solid thin film, or a paste. ([0034]), wherein the ion exchange source can be applied by the traditional method of immersion in a salt bath ([0024]), spray coating, roll coating, molding, or brush coating ([0035]). Graner further teaches the ion exchange source comprises different alkali metal salt comprising a plurality of alkali metal cations, including sodium, potassium, and silver salts ([0037]). Garner also teaches general method steps include contacting the glass surface with an ion exchange source at room temperature ([0061], [0063]), heating the ion exchange source on the glass surface with a laser to effect removal of components used in the ion source transfer process including water, solvent, binder and other components used for enabling transfer, and further heating so as to initiate ion exchange with the glass article ([0043]), wherein heating to a temperature of about 300°C or even 400°C is needed to produce a salt melt ([0034], [0061]) from the first alkali metal and to replace an alkali metal cations in the glass article with the first alkali metal cations in the salt to form a chemically strengthened glass article ([0063]-[0065]). Garner provides an example wherein the glass article after the ion exchange process has a measure depth of compression of 18 µm and a compressive stress of 610 MPa ([0064]). Garner essentially teaches the method steps of applying a solution comprising a first alkali metal salt and a binder to form a coating on a surface of an amorphous glass article having a thickness in the range of 50-300µm at room temperature, removing the binder, thereby forming a second coating comprising the first alkali metal salt, heating the glass based article and second coating to a temperature of about 300-400°C to form a melt from the first alkali metal and to replace an alkali metal cation in the glass article with the first alkali metal to form a chemically strengthened glass article with a compressive stress layer extending from the surface of the article to a depth of 18 µm and maximum compressive stress of 610 MPa.
However, Garner doesn’t offer certain specifics, such as an aqueous solution with two alkali metal salts, and an organic binder. Denry also teaches a method of chemically strengthening a glass-based article (col. 4 lines 42-45) comprising an ion exchange process. Like Garner, Denry teaches the ion exchange process comprises preparing an salt mixture and spraying the mixture onto the surface of the glass article. Denry specifies the method comprises applying an aqueous precursor solution comprising an organic binder, a first alkali metal salt comprising a plurality of first alkali metal cations, and a second alkali metal salt comprising a plurality of second alkali metal cations to a surface of the glass based article to form a first coating on the surface (col. 5 lines 55-61, 66-67, col. 6 lines 40-44), wherein the aqueous precursor solution is applied to the surface at room temperature (since the coating is applied before any heat treatment step), removing the organic binder to form a second coating comprising the first alkali metal salt and the second alkali metal salt in solid form (col. 6 lines 44-46, 50-53), and heating the glass based article and the second coating at a temperature in a first range from about 350°C to about 500°C (2nd heat treatment in tables I and II) to form a melt from the first alkali metal and to replace third alkali metal cations in the glass based article with the first alkali metal cations to form a chemically strengthened glass based article (col. 6 lines 58-67, col. 7 lines 1-10, 43-60, i.e. example IV), thereby providing for a thick compressive stress layer at the surface (col. 10 lines 59-61). Denry teaches using an organic binder can assist the application of the solution (col. 6 lines 43-44) and the use of a double ion exchange provides for higher strength to the glass article (col. 3 line 55-58). Accordingly, it would have been obvious to one of ordinary skill in the art at the time of the invention to have similarly used an aqueous solution comprising an organic binder and double alkali metal salts as the ion exchange source in process of Garner, as an organic binder would aid in the application of the ion exchange mixture on the surface of the glass article, and double ion exchange would provide for added strength, as taught by Denry.
Regarding claim 4, Garner and Denry further teach the alkali metal salts comprises sulfates, nitrates, halides or phosphates ([0037], col. 3 lines 63-65, respectively).
Regarding claims 7-8, Garner teaches the ion exchange process comprises exchanging potassium ions in the metal salt with sodium ions within the glass article, wherein the potassium ions have a larger ionic radius than the sodium ions ([0074]). Denry also teaches sodium cations are exchanged for lithium cations in the glass article, wherein sodium cations has a larger ionic radius than that of lithium cations (col. 10 lines 53-56).
Regarding claim 9, Garner teaches the glass article comprises a soda lime glass ([0030]), or an alkali aluminosilicate glass, wherein the alkali aluminosilicate glass comprises 61-75 mol% SiO2, 7-15 mol% Al2O3, 0-12 mol% B2O3, 9-21 mol% Na2O, 0-4 mol% K2O, 0-7 mol% MgO, and 0-3 mol% CaO, which satisfies limitations of option “b” of claim 9 ([0061]).
Regarding claim 10, Garner and Denry further teaches the aqueous precursor solution can be applied by spraying onto the surface ([0035], col. 6 lines 39-42, respectively).
Regarding claim 12, Garner teaches heating the glass article with the coating to 400°C ([0061]) and heat treated with a laser for up to 20 minutes ([0066]). Denry teaches a treatment temperature for ion exchange of 450°C for 30 minutes (col. 9 lines 29-32). Denry further teaches the treatment time is a result effective variable for controlling the amount of exchange/diffusion (col. 6 lines 58-64, col. 7 lines 10-12).
Regarding claim 14, Denry also teaches a binder such as gum arabic (col. 6 line 43), which appears to be a rheological modifier.
Claims 3 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Garner et al. (2015/0044445) and Denry et al. (5,705,273) as applied to claim 1 above, and further in view of Chang et al. (2015/0210590). Regarding claim 3, Garner teaches an example of a compressive stress layer with a maximum compressive stress of 610 MPa ([0064]). Regarding claim 13, Garner teaches the glass article has a thickness of less than 100µm ([0032]). However, Garner doesn’t specify a bend radius of the thin glass article. Chang teaches a glass based article that has been subjected to chemically strengthening so as to produce thin glass articles suitable for use as flexible displays for electronic devices. Chang teaches it is desirable for the strengthened thin glass article to have a thickness in the range of 25 µm to 125 µm and a minimum bend radius of 3mm ([0008]) in order to provide a flexible display for electronic devices that are foldable. Accordingly, it would have been obvious to one of ordinary skill in the art at the time of the invention to have provided for a thin glass article that has a minimum bend radius of 3 mm, so as to provide for a glass article suitable for use as flexible display in electronic devices, as taught by Chang.
Claims 5-6 are rejected under 35 U.S.C. 103 as being unpatentable over Garner et al. (2015/0044445) in view of Denry et al. (5,705,273) as applied to claim 1 above, and further in view of Postupack et al. (2004/0221615). Garner teaches the ion exchange source comprises potassium, such as potassium nitrate or potassium phosphate ([0037]). Denry also teaches employing a solution comprising potassium for the ion exchange (col. 5 lines 59-67, table 2). Denry further teaches the salt includes nitrates and phosphates (col. 6 lines 9-11). However, Garner and Denry don’t specify a combination of a nitrate and phosphate salt. Postupack teaches chemical strengthening of a glass article using a solution comprising potassium (abstract). Postupack teaches known potassium salts include KNO3, K3PO4, K2SO4, and KCl, which can be used in combination ([0007],[0008], [0013],[0018]). Postupack teaches a prior art that exemplifies the combination of KNO3 and K3PO4 ([0013]). Postupack further teaches one skilled in the art can determine the suitable combination of potassium salts that would provide for a liquid salt bath above an annealing point of the glass and a solid/semi-solid salt at the strengthening temperature through routine experimentation, as this would provide for a roughly uniform coating on the glass article during the heat treatment, and hence uniform strengthening. Postupack teaches a prior art that exemplifies the combination of KNO3 and K3PO4 ([0013]), as it provides a low melting point salt and a high melting point salt. Accordingly, it would have been obvious to one of ordinary skill in the art at the time of the invention to have try the combination of KNO3 and K3PO4 salts for the strengthening solution of Garner and Denry, as there are a finite number of potassium salts to choose from and Postupack teaches the combination of salts is a result effective variable for providing a uniform coating on the glass article.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Garner et al. (2015/0044445) and Denry et al. (5,705,273) as applied to claim 1 above, and further in view of Gates, Jr. (3,917,773). Denry teaches applying a binder, such as gum arabic (col. 6 lines 43-44) and removing the binder by heating the glass based article with the first coating (col. 6 lines 44-46) before the heat treatment step, but doesn’t specify a temperature. Gates teaches a method for producing spherical lens, comprising pressing ceramic granules coated with an organic binder and glass frit to form a porous sphere (col. 7 lines 45-47), drying the sphere (col. 7 lines 64-66), and heating the sphere to remove the binder at a temperature of about 400°C (col. 8 lines 1-6). Gates teaches the binder can be methyl cellulose (col. 7 line 47) or other substitutes including gum arabic (col. 9 lines 61-68). Accordingly, it would have been obvious to one of ordinary skill in the art at the time of the invention to have employed a similar temperature, of 400°C, to remove the binder of Denry, as Gates teaches such temperature predictably provides for successful removal of a binder comprising gum arabic.
Response to Arguments
Applicant's arguments filed November 3, 2025 have been fully considered. Applicant’s arguments with respect to claim 1 have been considered but are moot because the new ground of rejection does not rely on the same references applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
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/QUEENIE S DEHGHAN/Primary Examiner, Art Unit 1741