DETAILED 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.
Claims 1 and 3-20 are rejected under 35 U.S.C. 103 as being unpatentable over Charles et al. (2020/0156980). Regarding claims 1 and 20, Charles discloses a method for manufacturing glass comprising preparing a mixture of raw materials of glass, secondary glassmaking raw materials, and calcium oxide ([0098]), wherein the raw materials include water, sand, and sodium carbonate mixed in mass proportions of between 0 and 5%, 40 an 65%, and more than 0 and no more than 25% respectively ([0042]). Charles also teaches adding calcium oxide in a mass proportion of between 1 and 20% of the mixture ([0040]) and demonstrates examples wherein the calcium oxide was added at the same time as the raw materials ([0049]-[0056]). Charles also teaches an example using quicklime C having a particle size of caliber 4/8 mm, which comprises a predominance of the particle size in the range of 4 mm to 8 mm ([0055]), and an example using quicklime D having a particle size with D50 at 1.2mm. Charles explains quicklime D (with D50 at 1.2mm) produced a lot of batch dust ([0059]), while quicklime C (caliber 4/8 mm) had low heating and little dust (fig. 2 [0057], [0059]). This would suggest to one skilled in the art who is concerned with dust generation, would lean towards calcium oxide particles having larger particle size. Charles teaches a concern with providing for a mixture with a low generation of dust ([0015]), and recognizes that smaller particles generates large amount of dust, which leads to increased corrosion of the furnace, loss of material, and accumulation downstream ([0012]-[0014]). Charles also teaches maximizing the amount of calcium oxide particles with a size greater than 0.1 mm to avoid batch dusts ([0066]), which suggests screening out all dust particles before use. While Charles doesn’t specify calcium oxide with a granulometry of more than 97% do not pass through a 0.125 mm sieve and more than 96% do not pass through a 0.5 mm sieve, it would have been obvious to one of ordinary skill in the art at the time of the invention to have tried calcium oxide particles having such granulometry, in light of the teachings and findings in the examples of Charles. More specifically, it is taught that dusts generation must be reduced, that smaller particles generates large amount of dust, particles, calcium oxide particles having a size above 0.1mm should be maximized, and particles with particle size of caliber 4/8 mm does not generate much dust. Accordingly, it would have been obvious to one of ordinary skill in the art at the time of the invention to have minimized or even eliminate fines in the calcium oxide so that greater than 97% do not pass through a 0.125 mm sieve. Furthermore, in order to provide particles having caliber 4/8 mm, it would have been obvious to one of ordinary skill in the art at the time of the invention to have optimized the removal of small particles for the calcium oxide to have a granulometry of at least 96% do not pass through a 0.5 mm sieve and more than 95% by mass does not pass through a sieve of 1 mm (claim 20).
Regarding claim 3, the mixture of water, sand, calcium oxide and sodium carbonate has a moisture level of no more than 5% ([0022]).
Regarding claim 4, the sodium carbonate has a granulometry with less than 5% passing through a sieve of 0.075 mm, less than 15% passing through a sieve of 0.150 mm, and less than 5% not passing through a sieve of 0.600 mm ([0021]).
Regarding claim 5, the calcium oxide comprises by mass 0.16 ppm of Fe2O3, which is less than 1000 ppm ([0068]).
Regarding claim 6, an initial temperature of the raw materials is at least 30°C ([0025]).
Regarding claims 7-8, as discussed above in claim 1, it is suggested to remove all the dust when maximizing the amount of particles having a size greater than 0.1mm, which suggests the calcium oxide has a granulometry such that more than 98% does not pass through a sieve of 0.08 mm or a sieve of 0.125mm.
Regarding claim 9, Charles suggests the calcium oxide has a d50 granulometry of between 1 and 4 mm ([0028], [0054]).
Regarding claim 10, the sand is dry ([0031]).
Regarding claim 11, the water is present in the sand ([0032]).
Regarding claim 12, the calcium oxide is devoid of any intentional addition of aluminum oxide ([0033]), and cullet is added to the mixture, in a mass proportion of between 5 and 40% of the mixture ([0034]).
Regarding claim 13, the mixture is prepared in the solid state ([0035]).
Regarding claim 14, the mixture of glass raw materials is prepared at a temperature of between ambient temperature and ambient temperature plus 20°C, and the mixture of glass raw materials is prepared without addition of thermal energy ([0035]-[0036], claim 17).
Regarding claim 15, the mixture of glass raw materials is loaded into an electric furnace ([0039]).
Regarding claim 16, Charles further teaches melting the mixture by heating with a burner, wherein an oxidant supplied to the burner is oxygen ([0040]-[0041]).
Regarding claim 17, the water, sand, sodium carbonate and calcium oxide are present in mass proportions of between 0 and 5%, 40 and 65%, 1 and 25%, and 1 and 20%, respectively ([0042]).
Regarding claims 18-19, Charles teaches example comprising limestone, which is calcium carbonate. Charles recognizes certain benefits with limestone, such as reduced cost ([0013]), small temperature increase with use of limestone ([0056]) and low generation of dust ([0059], [0063]). As limestone is a recognized and common source for CaO in the glass, it would have been obvious to one of ordinary skill in the art at the time of the invention to have explored using limestone in conjunction with quicklime (CaO), as it would provide for benefits, such as reducing generation of dust. Furthermore, just as the CaO is added within 10 minutes in a mass proportion of between 1 and 20% of the mixture (as discussed in claim 1), it would have been obvious to have added the calcium carbonate simultaneously with the calcium oxide with a similar content, as both are the source for CaO in the glass.
Response to Arguments
Applicant's arguments filed April 28, 2026 have been fully considered but they are not persuasive. Applicant appears to be arguing unexpected results for using calcium oxide particles having a granulometry such that more than 97% by mass does not pass through a sieve of 0.125mm and more than 96% does not pass through a sieve of 0.5mm. To support the argument, applicant notes a feature not accounted for in the rejection, including an unexpected increase in output from a decrease in fines. Applicant points to batch 3 in [0094] and batch 4 in [0096] for higher order effects and lower than expected energy consumption. This argument is not sufficient evidence for unexpected results as applicant fails to provide technical data comparing the batches from Charles to batches 3 and 4 of the claimed invention. Paragraphs [0094] and [0096] do discussed low than expected energy consumption, but it appears the energy consumption is the same as the reference batches (i.e. batches of Charles). Furthermore, the feature of better than expected energy consumption is not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Applicant further argues the delay of 5 minutes in [0056] has no connection to the time of introducing the quicklime. As noted by applicant, [0049] teaches the ingredients are added simultaneously. This satisfies the claimed limitation of “within a time of less than 10 minutes from adding the raw materials”.
Applicant also argues quicklime D was not tested in phasing or firing tests or participated in the size measurements. It is unclear how this is relevant to the rejection. It is also unclear what is meant by “the skilled artisan would not have retained the quicklime D….or quicklime C”. Charles teaches in [0066], a quicklime containing a maximum amount of particles with particle size of greater than 0.1mm and below 4mm, which clearly suggests a preference for quicklime D or C.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to QUEENIE S DEHGHAN whose telephone number is (571)272-8209. The examiner can normally be reached Monday-Friday 8:00-4:30.
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/QUEENIE S DEHGHAN/Primary Examiner, Art Unit 1741
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