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 .
DETAILED ACTION
Information Disclosure Statement (IDS)
The information disclosure statements (IDS) submitted on 10/10/2024, 1/13/2025 and 3/12/2026 is/are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements are being considered by the examiner. Please refer to applicant’s copy of the 1449 herewith.
Election/Restrictions
Applicant’s election without traverse of claims 1-16, drawn to a method, in the reply filed on 05/11/2026 is acknowledged. Claims 1-27 are pending.
The Examiner would like to communicate that International Search Report findings are not binding to National Stage Examination. Also, patentability standards vary between US Practice and International Practice. The application will be examined on its own merits under US Practice.
Claim Interpretation
Regarding Claim(s) 1-3, 5-14 – The Examiner reiterates understanding of the word “about” as outlined in the Specification.
Examiner Note: A method is defined as a series of actions (MPEP 2106 (I), i.e., “processes…defines “actions”; inventions that consist of a series of steps or acts to be performed). Thus, since methods are defined by actions, the method is given weight only to the extent that it impacts the method in a manipulative sense. See Ex parte Pfeiffer, 135 USPQ 31, noting “recited structural limitations must affect method in manipulative sense and not amount to mere claiming of a use of a particular structure”. . Below is/are a list of claims/limitations that are structural limitations or mere outcomes of the method, (not a method):
Regarding Claim 2 – “open porosity of the porous glass sheet is greater than about 28%” is a mere outcome of a method, not a method.
Regarding an aspect of Claim 8 – “the consolidated glass sheet comprising a dielectric constant Dk less than about 4.0 when measured at 10 GHz using a split post dielectric resonator” is a mere outcome of the method, not a method.
Regarding Claim 9 – “ Dk less than about 3.5 when measured at 10 GHz using a split post dielectric resonator” is a mere outcome of the method, not a method.
Regarding Claim 10 – “the consolidated glass sheet comprising a loss tangent Df less than about 0.0075 when measured at 10 GHz using the split post dielectric resonator” is a mere outcome of the method, not a method.
Regarding Claim 12– “the consolidated glass sheet comprising a loss tangent Df less than about 0.003 when measured at 10 GHz using the split post dielectric resonator” is a mere outcome of the method, not a method.
Regarding Claim 13– “ Df less than about 0.001 when measured at 10 GHz “ is a mere outcome of the method, not a method.
Claim Rejections - 35 USC § 103
The following is a quotation of pre-AIA 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
(a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under pre-AIA 35 U.S.C. 103(a) are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims under pre-AIA 35 U.S.C. 103(a), the examiner presumes that the subject matter of the various claims was commonly owned at the time any inventions covered therein were made absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and invention dates of each claim that was not commonly owned at the time a later invention was made in order for the examiner to consider the applicability of pre-AIA 35 U.S.C. 103(c) and potential pre-AIA 35 U.S.C. 102(e), (f) or (g) prior art under pre-AIA 35 U.S.C. 103(a).
Claims 1-6, 8-13, 15-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over U.S. Patent
2,215,039 by Hood039 et. al (herein “Hood039”) and in further view of U.S. Patent 2,221,709 by Hood
et. al. (herein “Hood709”) and in further view of JP2016098118A (English language translation of the
Description and provided herewith and referenced herein) by Mushiake et. al. (herein “Mushiake”).
Regarding Claim 1 – Hood039 teaches
A method of making a glass article; Col 1 lines 25-26, “…method of treating the selected borosilicate and the products obtained…”
comprising,
forming a molten glass; Col 1 lines 49-50, “…the selected glass is melted…”
the molten glass undergoing spinodal decomposition to produce a phase separated molten glass comprising a first phase, a second phase ; Page 1 Col 1 lines 3-10, “…on the proper heat treatment separate into two phases…one of these phases is very rich in silica called the soluble phase…the other phase very rich in alkali and boric oxide call the insoluble phase…”
and a total SiO2 content in a range from about 59 mol% to about 69 mol% and a B203 content in a range from about 9 mol% to about 20 mol%; Page 4 Col 1 lines 16-24. A PHOSITA can calculate the wt% and convert to mol %. The composition equation, in wt%, is below in regard to lithia (Li2O) as the alkali, as well as a summary table.
SiO2 = 60-82.5; alkali (Na2O) = 11- (0.25K) to 3 +.(05K); boric oxide (B2O3) = 29 – (0.75 K) to 37 (-1.05K, ) (Page 3 Col2 lines 59-66)
Where K = the excess % of SiO2 over the minimum (minimum = 60).
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Hood039 does not specifically state the composition disclosed is measured in weight or mol percentages. Both weight and mol percentages overlap the claimed ranges.
SIO2 mol% range: 58.48-84.74, which reads on the instant claim.
B2O3 mol% range: 10.99 – 33.67, which reads on the instant claim.
and exposing the glass sheet to a first acid solution at a temperature between about 60°C to about 95°C for about 16 hours to about 24 hours to remove at least a portion of the second phase from the glass sheet and obtain a porous glass sheet comprising a total silica content greater than about 95 mol%; Col 1 lines 52-54, Col 2 lines 24-25, 28-30, 47-49, “It is then fabricated…into…sheets”, “…the glass…is immersed in….3 normal hydrochloric (3N HCl) acid…”, “…the glass is kept immersed in the acid bath for a length of time…this length of time will approximate 1 day (24hrs) for 1mm of glass…”, “…the acid treatment…will cause complete solution of the soluble phase”, “…the removal of the soluble phase leaves the silica phase…rigid and porous”, “…after the article has been leached…it is subject to a vitrifying heat treatment. The vitrified article is now composed of almost pure vitreous silica and...about 5% B2O3 and about 0.5% Na2O” where the alkali is Na2O in this instance but could also be Li2O (Col 1 lines 38-39 Col 3 lines 21-24). Therefore, the vitreous silica would be 94.5%, or about 95%. As the porous sheet is the same article that was vitrified, the porous sheet also contains vitreous silica of 94.5% or about 95%.
While Hood039 teaches exposing the glass sheet to a first acid solution for about 16 hours to about 24 hours to remove at least a portion of the second phase from the glass sheet and obtain a porous glass sheet comprising a total silica content greater than about 95 mol%, at a temperature of 98°C, as well as stating the length of time in the acid bath depends on temperature of the bath and glass thickness (Col 2 lines 33-40), Hood039 does not disclose the acid processing,
at a temperature between about 60°C to about 95°C
In a similar endeavor of leaching phase separated R2O-SiO2-B2O3 glass compositions where the final glass article contains > 94% SiO2 (Col lines 17-23) where the phase separated glass is leached with an acid (Col 2 lines 7-8), Hood709 discloses leaching the glass with a 3 normal hydrochloric acid at 90°
C ( Page 1 Col 1 lines 7-8) and for an example VI (which meets the SiO2 mol% range and is very close to the B2O3 mol% range, and where the wt% Na2O is within the range of Hood039, that the 3N acid may be at a temperature of 60°C for a glass thickness of 1mm (Page 3 Col 2 lines 60-65) . Hood709 discloses the claimed invention except for the exact range of B2O3 and Na2O used for the temperature of the acid leaching. It would have been obvious to one of ordinary skill in the art prior at the time of the effective filing date of the claimed invention to use the temperature range of Hood709 in the process of Hood039 as one would be motivated to do so for the purposes of controlling the swelling/shrinking of the glass to control the stresses in the leaching step, as noted by Hood039 (Page 1 Col 1 lines 40-45).
While Hood039 discloses that glass undergoes spinodal decomposition in thermal treatment process after the formed glass article is cooled (Col 2 lines 17-24) and the glass is melted and then fabrication to desired articles including sheets (Col 1 lines 50-55), and Hood709 discloses phase separated glass that is phase separated by heat treatment and then leached with acid (Col 2 lines 1-8), the combination does not disclose,
the molten glass undergoing spinodal decomposition to produce a phase separated molten glass comprising a first phase, a second phase ;
drawing the phase separated molten glass into a glass sheet;
In an analogous endeavor of creating borosilicate phase separated glass sheets that contain R2O material (Page 2, Para.8), Mushiake discloses a phase separated glass that has two phases, one of 40% mass and one of 50% mass (Page 2, Para. 6 and Para. 10) from an overall glass composition (Page 2 Para. 8). A PHOSITA can perform the reverse calculation from the phase separated composition and their respective mass % to determine an overall starting composition of glass in mol% that can be phase separated. A summary table is below and captures a potential Mushiake composition within the Mushiake ranges that aligns with Hood039 composition and the instant claim:
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Further, A PHOSITA would know that the insoluble separated phase is the phase without RO and R2O components and the soluble phase is the separated phase with RO and/or R2O components. Mushiake cites that the phase separation glass of the invention has a phase separation temperature higher than the liquid phase temperature that allows to phase divide the glass at the time of shaping (i.e. when the glass is still molten) and that the phase separation of glass is formed by an overflow down draw method (Page 3 Para. 6) with slow cooling after shaping (Page 3 Para.12)
It would have been obvious to one of ordinary skill in the art prior at the time of the effective filing date of the claimed invention to use the down draw and slow cooling method of Mushiake to form the glass articles of Hood039, as the glass composition of Hood039 is viable for the Mushiake down draw and slow cooling method. One would have been motivated to do so for the purposes of making a separate heat treatment step for causing phase separation unnecessary and the production cost of the phase separation can be reduced, as noted by Mushiake (Page 2 Para. 9).
Regarding Claim 2 - Hood039, Hood709, and Mushiake in the rejection of claim 1 above teaches all of
the limitations of claim 1.
Hood039 teaches wherein,
an open porosity of the porous glass sheet is greater than about 28%; Page 2 Col 2 lines 42-50, “…this porous structure can be heated until…a collapsing of the porous channels…resulting in…solid glass of zero porosity”, “ During this operation…a shrinkage in dimension occurs…a volume loss of equivalent to that of the removed phase…about 20% of the glass”. It understood that the porosity was then 20% before consolidation. Hood039 discloses the claimed invention except for the claimed porosity. It would have been obvious to one having ordinary skill in the art at the time of the effective filing date of the claimed invention to optimize the porosity, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. One would have been motivated to optimize the porosity for the purpose of obtaining a porous article for potential use that meets the requirements for articles such as semi-permeable membranes and supports for catalysts, as noted by Hood039 (Page 2, lines 56-62). Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover optimum working ranges by routine experimentation. It would have been obvious to one having ordinary skill in the art to have determined the optimum values of the relevant process parameters through routine experimentation in the absence of a showing of criticality. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235.
Regarding Claim 3 and 4 - Hood039, Hood709, and Mushiake in the rejection of claim 1 above
teaches all of the limitations of claim 1.
Hood039 teaches wherein,
first acid solution comprises about 5 wt% to about 40 wt% of at least one of HCI, H2SO4, HNO3, HF, or H3PO4; Claim 3
the first acid solution comprises HCl; Claim 4
Col 2 lines 28-30, ““…the glass…is immersed in….3 normal hydrochloric (3N HCl) acid…”. A PHOSITA can make the calculation that a 3 normal HCl acid solution is 10.8 wt% HCl.
Regarding Claim 5 - Hood039, Hood709, and Mushiake in the rejection of claim 4 above teaches all of
the limitations of claim 4.
Hood039 discloses a 10.8% wt% HCl solution but does not disclose,
the first acid solution comprises about 5 wt% HCl.
Hood709 discloses a leaching process using 1 normal (1N) HCl with higher temperatures up to the
boiling temperature of the acid (where a PHOSITA can calculate for 1N HCl is 100°C, and 1N is 3.55wt%
HCl ) and 3 normal HCl (10.8 wt% HCl, same as Hood039) at 60°C. Hood709 discloses the claimed
invention except for the claimed value of 5wt% HCl. It would have been obvious to one of ordinary skill
in the art prior at the time of the effective filing date of the claimed invention to optimize the wt% HCl
since it has been held that where the general conditions of a claim are disclosed in the prior art,
discovering the optimum or workable ranges involves only routine skill in the art. One would have been
motivated to optimize the wt% HCl for the purpose of adjusting the leaching rate depending on the
thickness of the ware, as noted by Hood709 (Page 3, Col 2 lines 59-66).
Regarding Claim 6 - Hood039, Hood709, and Mushiake in the rejection of claim 1 above teaches all of
the limitations of claim 1.
While Hood039 discloses the use of HCl between 5 wt% to about 40 wt% as a first acid solution, Hood
does not disclose,
the first acid solution comprises about 5 wt% to about 40 wt% of at least one of citric acid or
acetic acid.
While Hood039 doesn’t teach the use of citric or acetic acid it would have been obvious to one
having ordinary skill in the art at the time of the effective filing date of the claimed invention to
use other common available acids at the same concentration levels. A person of ordinary skill
has good reason to pursue the known option within his or her technical grasp. If this leads to the
anticipated success, it is likely the product not of innovation but of ordinary skill and common
sense." KSR int'l Co. v. Teleflex Inc., 127 S.Ct. 1727,82 USPQ2d 1385 (2007). One would be
motivated to do so, as citric acid and acetic acid are weaker acids than HCl, for the common
industrial purpose to promote process safety.
Regarding Claim 8 - Hood039, Hood709, and Mushiake in the rejection of claim 1 above teaches all of
the limitations of claim 1.
Hood039 teaches wherein,
further comprising heating the porous glass sheet to a consolidation temperature between
about 900°C to about 1100°C for about 1 hour to about 24 hours to consolidate the porous glass
sheet and obtain a consolidated glass sheet; Page 2 Col 1 lines 32-36, 44-46, “After the article is leached…a vitrifying heat treatment in order to…convert the structure to a non-porous vitreous condition”, “The temperature is carried to a maximum of 900°C to 1000°C, at which it is held for a short time”. Hood039 discloses the claimed invention except for the exact hold time of the consolidation temperature. It would have been obvious to one having ordinary skill in the art at the time of the effective filing date of the claimed invention to optimize the exact hold time of the consolidation temperature since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. One would have been motivated to optimize the exact hold time of the consolidation temperature for the purpose of ensuring full consolidation. Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover optimum working ranges by routine experimentation. It would have been obvious to one having ordinary skill in the art to have determined the optimum values of the relevant process parameters through routine experimentation in the absence of a showing of criticality. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235.
The combination does not disclose a consolidated glass sheet such that
the consolidated glass sheet comprising a dielectric constant Dk less than about 4.0 when
measured at 10 GHz using a split post dielectric resonator.
As the Examiner has established that the prior art product is identical or substantially identical in
structure or are produced by identical or a substantially identical processes via a combination of
references, a prima facie case of either anticipation or obviousness will be considered to have been
established over functional limitations that stem from the claimed structure. In re Best, 195 USPQ 430,
433 (CCPA 1977), In re Spada, 15 USPQ2d 1655, 1658 ( Fed. Cir. 1990). The prima facie case can be
rebutted by evidence showing that the prior art products do not necessarily possess the characteristics
of the claimed products. in re Best, 195 USPQ 430, 433 (CCPA 1977).
Regarding Claims 9 , 10, 12 and 13 - Hood039, Hood709, and Mushiake in the rejection of claim 8
above teaches all of the limitations of claim 8.
Dk is less than about 3.5 when measured at 10 GHz using the split post dielectric resonator;
Claim 9.
the consolidated glass sheet comprises a loss tangent Df less than about 0.0075 when measured at 10 GHz using the split post dielectric resonator; Claim 10.
the consolidated glass sheet comprises a loss tangent Df less than about 0.003 when measured at 10 GHz using the split post dielectric resonator; Claim 12.
Df is less than about 0.001 when measured at 10 GHz; Claim 13.
As the Examiner has established that the prior art product is identical or substantially identical in
structure or are produced by identical or a substantially identical processes via a combination of
references, a prima facie case of either anticipation or obviousness will be considered to have been
established over functional limitations that stem from the claimed structure. In re Best, 195 USPQ 430,
433 (CCPA 1977), In re Spada, 15 USPQ2d 1655, 1658 ( Fed. Cir. 1990). The prima facie case can be
rebutted by evidence showing that the prior art products do not necessarily possess the characteristics
of the claimed products. in re Best, 195 USPQ 430, 433 (CCPA 1977).
Regarding Claim 11 - Hood039, Hood709, and Mushiake in the rejection of claim 8 above teaches all of
the limitations of claim 8.
Hood039 teaches wherein,
the consolidation temperature is equal to or greater than about 1000°C; Page 2 Col 1 lines 32-36, 44-46, “After the article is leached…a vitrifying heat treatment in order to…convert the structure to a non-porous vitreous condition”, “The temperature is carried to a maximum of 900°C to 1000°C”.
Regarding Claim 15 - Hood039, Hood709, and Mushiake in the rejection of claim 1 above teaches all of
the limitations of claim 1.
While Hood039 discloses the selected glass is melted in the usual way in a tank furnace, fabricated in the
usual way into desired articles (Page 1 Col 1 lines 50-55) , and Hood709 discloses and melting glass in a
continuous tank ( Page 3 Col 1 line 55), neither disclose,
the drawing the molten glass into the glass sheet comprises flowing the molten glass over
converging forming surfaces of a forming body as separate streams of the molten glass, the
separate streams of the molten glass joining along a bottom edge of the forming body.
Mushiake further discloses the phase separation glass is formed by an overflow down draw method
(Page 3 Para. 6). One skilled in the art would know the phrase overflow down draw method is
synonymous with the fusion draw process, which is the nature of the instant claim. A fusion draw is
common in the art of glass drawing. It would have been obvious to one of ordinary skill in the art at the
time of the effective filing date of the claimed invention to use the overflow down draw (fusion draw)
of Mushiake to form the phase separated glass of Hood039, as one would be motivated to do so for the
foundational industrial reasons to use fusion draw – to obtain sheets of glass without the need to grind
at least one of the two opposing surfaces. A person of ordinary skill has good reason to pursue the
known option within his or her technical grasp. If this leads to the anticipated success, it is likely the
product not of innovation but of ordinary skill and common sense." KSR int'l Co. v. Teleflex Inc., 127 S.Ct.
1727,82 USPQ2d 1385 (2007).
Regarding Claim 16 - Hood039, Hood709, and Mushiake in the rejection of claim 1 above teaches all of
the limitations of claim 1.
While Hood039 discloses the selected glass is melted in the usual way in a tank furnace, fabricated in the
usual way into desired articles (Page 1 Col 1 lines 50-55) , and Hood709 discloses and melting glass in a
continuous tank ( Page 3 Col 1 line 55), neither disclose,
the drawing the molten glass into the glass sheet comprises flowing the molten glass from a slot positioned in a bottom of a vessel.
Mushiake further discloses the phase separation glass is formed, in addition, by redraw method, float
method , roll-out method, or the like, (Page 2 Para. 13) indicating common methods of drawing glass
can be employed, which would include slot draw ( which a PHOSITA would know is the nature of the
instant claim). Mushiake discloses the claimed invention except for specifically a slot draw. It would
have been obvious to one of ordinary skill in the art prior at the time of the effective filing date of the
claimed invention to use a slot draw of Mushiake for drawing the phase separable glass of Hood039,
one being motivated to do so for the common industrial reason of having the capability to obtain ultra-
thin glass sheets with smaller equipment footprint than fusion draw. A person of ordinary skill has good
reason to pursue the known option within his or her technical grasp. If this leads to the anticipated
success, it is likely the product not of innovation but of ordinary skill and common sense." KSR int'l Co. v.
Teleflex Inc., 127 S.Ct. 1727,82 USPQ2d 1385 (2007).
Claim 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hood039 et. al. and in
further view of Hood709 et. al. and in further view of by Mushiake et. al. and in further view of U.S.
Patent 3, 459,522 by Elmer et. al. (herein “Elmer”).
Regarding Claim 7 - Hood039, Hood709, and Mushiake in the rejection of claim 1 above teaches all of
the limitations of claim 1.
While the combination discloses processing to create phase separated and leachable borosilicate glass
where the leached porous glass is consolidated, and Hood039 cites the porous sheet is subjected to a
vitrifying heat treatment in order to dehydrate it and that heating should be done slowly due to the
evolution of water (Page 2 Col 1 lines 32-35, 40-43)) the combination does not disclose,
further comprising heating the porous glass sheet to a temperature between about 500°C to
about 700°C for about 45 minutes to about 75 minutes.
In a similar endeavor to processing phase separated glass by leaching, drying and consolidating (Col 1 lines 43-73) and where U.S. Patent 2,221,709 by Hood et. al. is specifically cited for borosilicate glass compositions (Col 1 lines 39-42), Elmer discloses a treating a porous high silica content glass body at a temperature within a range of 600°C to 1000°C for a sufficient time (Col 3 lines 14-16). Elmer discloses the claimed invention except for except for the exact time of the heating. It would have been obvious to one having ordinary skill in the art at the time of the effective filing date of the claimed invention to optimize the time of the heating, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. One would have been motivated to optimize the time of heating for the purpose of permeating the porous glass sufficiently to remove residual water from the porous glass, as noted by Elmer (Col 3 line 16, Col 2 lines 54-56). Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover optimum working ranges by routine experimentation. It would have been obvious to one having ordinary skill in the art to have determined the optimum values of the relevant process parameters through routine experimentation in the absence of a showing of criticality. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235.
Further, in regard to the temperature range of 600°C to 1000°C, overlapping ranges are prima facie evidence of obviousness. It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to have selected the portion of Elmer’s temperature range that corresponds to the claimed range. One would have the same motivation to do so as noted above regarding the time of the heat treatment. See MPEP 2144.05.
Claim 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hood039 et. al. and in
further view of Hood709 et. al. and in further view of by Mushiake et. al. and in further view of Elmer et.
al. and in further view of U.S Patent 2,348,704 by Adams (herein “Adams”).
Regarding Claim 14 - Hood039, Hood709, Mushiake, and Elmer in the rejection of claim 7 above
teaches all of the limitations of claim 7.
Hood039 discloses a hydrofluoric etching process which comprises dipping the article into a dilute
solution of hydrofluoric acid before acid leaching (Page 2 Col 1 lines 73-74), but fails to disclose,
further comprising exposing the porous glass sheet to a second acid solution comprising HF for
about 1 minute to about 15 minutes prior to the heating.
In an analogous endeavor of acid treating leachable alkali borosilicate glass with a two-step leaching
process (Col 2 lines 37-48), where the first acid leaching acid could be hydrofluoric acid (Page 2 Col 2
lines 1-2), Adams discloses, after the first acid treatment, the use of hydrofluoric acid for 60 seconds
(Page 2 Col 2 lines 40-41). As there were no steps of heat treating in between the leaching steps, the
leaching steps must come before any heating steps. It would have been obvious to one having ordinary
skill in the art at the time of the effective filing date of the claimed invention to use hydrofluoric acid for
the second leaching step, as one would be motivated to do so for the purposes of having the
hydrofluoric acid dissolve out the alkali and other compounds, and enlarges the pores of the silica
skeleton, as noted by Adams (Page 1, Col 2 lines 1-7).
Conclusion
The prior art made of record and not relied upon is considered pertinent to the applicant’s disclosure.
Elmer et. al (U.S. Patent 3, 592, 619) discloses leaching phase separated alkali borosilicate glass and consolidating the leached porous glass, where the leach acid is HCl, H2SO4, or HNO3 with a temperature of 90°C to 100°C, citing U.S Patent 2,221,709 by Hood et. al. as a basis.
Haller (U.S. Patent 3,549, 524 ) discloses leaching phase separated alkali borosilicate glass powder, where the leach acid is HCl.
Beaver (U.S. Patent 4,966,613) discloses leaching phase separated alkali borosilicate glass powder, where the leach acid is HCl.
Walsh et. al (U.S. Patent 9,731,996) discloses leaching phase separated alkali borosilicate glass powder, where the leach acid is HCl.
Miyasaka et. al. (USPGPUB 20170107142A1) disclose a method for creating phase separated glass in during the molten state of the glass.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHRISTOPHER PAUL DAIGLER whose telephone number is (571)272-1066. The examiner can normally be reached Monday-Friday 7:30-4:30 CT.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Alison Hindenlang can be reached on 571-270-7001. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/CHRISTOPHER PAUL DAIGLER/ Examiner, Art Unit 1741
/JODI C FRANKLIN/Primary Examiner, Art Unit 1741
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