WO2024112624A1

WO2024112624A1 - Vacuum insulated panel with multi-row seal

Info

Publication number: WO2024112624A1
Application number: PCT/US2023/080456
Authority: WO
Inventors: Scott V. Thomsen
Original assignee: LuxWall, Inc.
Priority date: 2022-11-23
Filing date: 2023-11-20
Publication date: 2024-05-30

Abstract

A vacuum insulating panel includes first and second substrates (e.g., glass substrates), a hermetic edge seal, a pump-out port, and spacers sandwiched between at least the two substrates. The gap between the substrates may be at a pressure less than atmospheric pressure to provide insulating properties. The vacuum insulating panel may include a multi-row edge seal structure.

Description

VACUUM INSULATED PANEL WITH MULTI-ROW SEAL

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to and claims priority on United States Provisional Application No. 63/540,729, filed September 27, 2023, the disclosure of which is hereby incorporated herein by reference in its entirety for all purposes. This application is also related to and claims priority on United States Provisional Application No. 63427645, filed November 23, 2022, to United States Provisional Application No. 63427657, filed November 23, 2022, and to United States Provisional Application No. 63427661, filed November 23, 2022.

FIELD

Certain example embodiments are generally related to vacuum insulated devices such as vacuum insulating panels that may be used for windows or the like, and/or methods of making same.

BACKGROUND AND SUMMARY

Vacuum insulated panels are known in the art. For example, and without limitation, vacuum insulating panels are disclosed in U.S. Patent Nos. 5,124,185, 5,657,607, 5,664,395, 7,045,181, 7,115,308, 8,821,999, 10,153,389, and 11,124,450, the disclosures of which are all hereby incorporated herein by reference in their entireties.

[0001] As discussed and/or shown in one or more of the above patent documents, a vacuum insulating panel typically includes an outboard substrate, an inboard substrate, a hermetic edge seal, a sorption getter, a pump-out port, and spacers (e.g., pillars) sandwiched between at least the two substrates. The gap between the substrates may be at a pressure less than atmospheric pressure to provide insulating properties. Providing a vacuum in the space between the substrates reduces conduction and convection heat transport, and thus provides insulating properties. For example, a vacuum insulating panel provides thermal insulation resistance by reducing convective energy between the two substrates, reducing conductive energy between the two transparent substrates, and reducing radiative energy with a low-emissivity (low-E) coating provided on one of the substrates. Vacuum insulating panels may be used in window applications (e.g., for commercial and/or residential windows), and/or for other applications such as commercial refrigeration and consumer appliance applications.

In certain example embodiments, there may be provided a vacuum insulating panel which may comprise: a first substrate; a second substrate; a plurality of spacers provided in a gap between at least the first and second substrates, wherein the gap is at pressure less than atmospheric pressure; a seal provided at least partially between at least the first and second substrates, wherein the seal may comprise a first seal layer; and wherein the first seal layer may comprise a first continuous seal layer portion comprising seal material that surrounds at least the gap as viewed from above, and a second continuous seal layer portion comprising seal material that also surrounds at least the gap as viewed from above, wherein the first and second continuous seal layer portions may be spaced apart from each other as viewed from above so that a space may be located between at least the first and second continuous seal layer portions.

In certain example embodiments, there may be provided a vacuum insulating panel which may comprise: a first glass substrate; a second glass substrate; a plurality of spacers provided in a gap between al least the first and second glass substrates, wherein the gap is at pressure less than atmospheric pressure; a seal provided at least partially between at least the first and second substrates, wherein the seal may comprise a first seal layer; wherein the first seal layer may comprise first and second substantially coplanar spaced apart seal layer portions each comprising seal material, wherein the first and second substantially coplanar seal layer portions may be spaced apart from each other so that a space is located between at least the first and second seal layer portions, and wherein the second seal layer portion may be located between at least first seal layer portion and the gap at pressure less than atmospheric pressure.

Technical advantage(s), for example, include one or more of: (a) improved insulative properties, including edge-of-glass performance; (b) may permit use of a smaller diameter laser beam(s) and/or lower power level(s) during firing and/or sintering of the seal to reduce induced transient thermal stress and/or micro-cracking of the ceramic sealing material; (c) may permit use of a smaller laser beam(s) and/or lower power level(s) during firing and/or sintering of the seal to reduce de-tempering of glass substrate(s); (d) may increase laser sintering speed compared to a single row edge seal by allowing use of a smaller laser beam(s) and/or lower power level(s); (e) desirable mechanical strength to pass asymmetric thermal stress testing such as due to satisfying a desirable cumulative seal width; (f) desirable mechanical strength and/or structure to obtain desired fragmentation cullet size for tempered glass safety testing under constrained edge conditions; and/or (g) provide desirable cross-sectional total width to improve hermiticity of the edge seal.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects, features, and/or advantages will become apparent and more readily appreciated from the following description of various example embodiments, taken in conjunction with the accompanying drawings. Thicknesses of layers/elements, and sizes of components/elements, are not necessarily drawn to scale or in actual proportion to one another, but rather are shown as example representations. Like reference numerals may refer to like parts throughout the several views. Each embodiment herein may be used in combination with any other embodiment(s) described herein.

Fig. 1 is a side cross sectional view of a vacuum insulating unit/panel according to an example embodiment. Fig. 2 is a schematic top view of a vacuum insulating unit/panel according to an example embodiment (e.g., see Figs. 1 and 3-4), showing a laser used in forming the edge seal during manufacturing, which may be used in combination with any embodiment herein including those of Figs. 1 and 3-9.

Fig. 3a is a side cross sectional view of an example edge seal for a vacuum insulating unit/panel according to an example embodiment, taken at the edge of a panel at Section line A - - A in Fig. 2, with example layer thicknesses, which may be used in combination with any embodiment herein including those of Figs. 1-9.

Fig. 3b is a side cross sectional view of an example edge seal for a vacuum insulating unit/panel according to an example embodiment, taken at the edge of a panel at Section line A - - A in Fig. 2, with example layer thicknesses, which may be used in combination with any embodiment herein including those of Figs. 1-9.

Fig. 3c is a side cross sectional view of an example edge seal for a vacuum insulating unit/panel according to an example embodiment, taken at the edge of a panel at Section line A - - A in Fig. 2, with example layer thicknesses, which may be used in combination with any embodiment herein including those of Figs. 1-9.

Fig. 3d is a top view of main seal layers, of the edge seal, of the embodiments of Figs. 1 and 3a-3c according to certain example embodiments.

Fig. 4 is a side cross sectional view of an example edge seal for a vacuum insulating unit/panel according to an example embodiment, taken at the edge of a panel at Section line A - - A in Fig. 2, with example layer thicknesses, which may be used in combination with any embodiment herein including those of Figs. 1-9.

Fig. 5 is a table/graph showing weight % and mol % of various compounds/elements in a main seal material according to an example embodiment (measured via non-carbon detecting XRF), which main seal material may be used in combination with any embodiment herein including those of Figs. 1-9. Fig. 6 is a table/graph showing weight % and mol % of various compounds/elements in a main seal material according to an example embodiment (measured via carbon detecting XRF), before and after laser treatment using an 808 or 810 nm continuous wave laser for edge seal formation, which main seal material may be used in combination with any embodiment herein including those of Figs. 1-9.

Fig. 7a is a table/graph showing weight % and mol % of various compounds/elements in a primer seal material according to an example embodiment (measured via carbon detecting XRF), before and after substrate tempering, which primer material may be used in combination with any embodiment herein (e.g., for one or both primer layers) including those of Figs. 1-9.

Fig. 7b is a table/graph showing weight % and mol % of various compounds/elements in a primer seal material according to an example embodiment (measured via fused bead XRF), before and after substrate tempering and laser firing of the main seal layer, which primer material may be used in combination with any embodiment herein (e.g., for one or both primer layers) including those of Figs. 1-9.

Fig. 8 is a table/graph showing an elemental analysis (non-oxide analysis) of weight % and mol % of various elements in each of a main seal material (left side in the figure), a pump-out tube seal material (center in the figure), and a primer seal material (right side in the figure), according to an example embodiment(s) (measured via WDXRF), before and after laser treatment using an 808 or 810 nm continuous wave laser to fire/sinter the main seal layer for seal formation, which various seal materials may be used in combination with any embodiment herein including those of Figs. 1-9.

Fig. 9 is a flowchart illustrating example steps in making a vacuum insulating panel according to various example embodiments, which may be used in combination with any embodiment herein including those of Figs. 1-8.

DETAILED DESCRIPTION The following detailed structural and/or functional description(s) is/are provided as examples only, and various alterations and modifications may be made. The example embodiments herein do not limit the disclosure and should be understood to include all changes, equivalents, and replacements within ideas and the technical scope herein. Hereinafter, certain examples will be described in detail with reference to the accompanying drawings. When describing various example embodiments with reference to the accompanying drawings, like reference numerals may refer to like components and a repeated description related thereto may be omitted.

Conventional insulated glass edge sealing systems and associated sintering and/or firing processes have shown it is possible to create a hermetically sealed vacuum insulating panel. However, conventional vacuum insulated glass perimeter sealing systems may suffer from one or more of the following drawbacks that hinder use of such products commercially: (1) significant de-tempering of the glass substrate(s) preventing or reducing a likelihood of the vacuum insulated panel meeting mandatory tempered glass safety codes due to overall reduction in the compressive surface stress across the device and/or the internal tensile stress; (2) significantly higher de-tempering rates around the periphery of the device relative to the center of the vacuum insulated panel resulting in a large compressive stress gradient that upon physical impact does not meet safety fragmentation requirements, due for example and without limitation at least to variations in resonant vibration frequencies; (3) lack of durability, for example due to thermally induced breakage or flaws from large asymmetric thermal stress across the unit and/or spacer induced cracks causing glass breakage; (4) lack of durability and/or hermiticity due to edge seal damage, cracks and/or flaws; (5) failures due to too much induced transient thermal stress; (6) significant thermal de-tempering of tempered glass resulting in higher unit breakage rates such as when installed in a final application; and/or (7) ceramic sealing glass-based edge seals having unfavorable edge of glass u-faclor due to a thermal bridge bewteen opposing substrates. Certain example embodiments herein may overcome at least one of these problems. Fig. 1 is a side cross sectional view illustrating a vacuum insulating panel 100 according to various example embodiments, and Fig. 2 is a schematic top view of an example vacuum insulating unit/panel 100 showing a laser used in sintering/firing the main seal layer 30 when forming the edge seal 3 during manufacturing (which may be used in combination with any embodiment herein). It should be noted that, in practice, such vacuum insulating panels/units may be oriented upside down or sideways from the orientations illustrated. Vacuum insulating panel 100 may be used in window applications (e.g., for commercial and/or residential windows), and/or for other applications such as commercial refrigeration and consumer appliance applications.

Referring to Figs. 1-2, a vacuum insulating panel 100 may include a first substrate 1 (e.g., glass substrate), a second substrate 2 (e.g., glass substrate), a hermetic edge seal 3 at least partially provided proximate the edge of the panel 100, and a plurality (e.g., an array) of spacers 4 provided between at least the substrates 1 and 2 for spacing the substrates from each other and so as to help provide low-pressure space/gap 5 between at least the substrates. Each glass substrate 1, 2 may be flat, or substantially flat, possibly comprising non-uniform surface features resulting from thermal heat treatment of glass, in certain example embodiments. Support spacers 4, sometimes referred to as pillars, may be of any suitable shape (e.g., round, oval, disc-shaped, square, rectangular, rodshaped, etc.) and may be of or include any suitable material such as stainless steel, aluminum, ceramic, solder glass, metal, and/or glass. Certain example support spacers 4 shown in the figures are substantially circular as viewed from above and substantially rectangular as viewed in cross section, and may have rounded edges. The hermetic edge seal 3 may include one or more of main seal layer 30, upper primer layer 31 , and lower primer layer 32. Each “layer” herein may comprise one or more layers. At least one thermal control and/or solar control coating 7, such as a multi-layer low-emittance (low- E) coating, may be provided on at least one of the substrates 1 and 2 in order to further improve insulating properties of the panel. The solar control coating 7 may be provided on substrate 1 or substrate 2, or such a solar control coating may be provided on both substrates 1 and 2. Each substrate 1 and 2 is preferably of or including glass, but may instead be of other material such as plastic or quartz. For example, one or both glass substrates 1 and 2 may be soda-lime- silica based glass substrates, borosilicate glass substrates, lithia aluminosilicate glass substrates, or the like, and may be clear, low iron, or otherwise tinted/colored such as green, grey, bronze, or blue tinted. Substrates 1 and 2, in certain example embodiments, may each have a visible transmission of at least about 40%, more preferably of at least about 50%, and most preferably of from about 60-80%. The vacuum insulating panel 100, in certain example embodiments, may have a visible transmission of at least 40%, more preferably of at least 50%, and most preferably from about 60-90%. The substrates 1 and 2 may be substantially parallel (parallel plus/minus ten degrees, more preferably plus/minus five degrees) to each other in certain example embodiments. Substrates 1 and 2 may or may not have the same thickness, and may or may not be of the same size and/or same material, in various example embodiments. When glass is used for substrates 1 and 2, each of the glass substrates may be from about 2-12 mm thick, more preferably from about 3-8 mm thick, and most preferably from about 4-6 mm thick. When glass is used for substrates 1 and 2, the glass may or may not be tempered (e.g., thermally tempered). Although thermally tempered glass substrates are desirable in certain environments, the glass substrate(s) may be heat strengthened. As known in the art, thermal tempering of glass typically involves heating the glass to a temperature of at least 585 degrees C, more preferably to at least 600 degrees C, more preferably to at least 620 degrees C (e.g., to a temperature of from about 620-650 degrees C), and then rapidly cooling the heated glass so as to compress surface regions of the glass to make it stronger. The glass substrates may be thermally tempered to increase compressive surface stress and/or central tension stress and to impart safety glass properties including small fragmentation upon breakage. When tempered glass substrates 1 and/or 2 are used, the substrate(s) may be tempered (e.g., thermally or chemically tempered) prior to firing/sintering of main edge seal material 30 (e.g., via laser) to form the edge seal 3. When heat strengthened glass substrates 1 and/or 2 are used, the substrate(s) may be heat strengthened prior to firing/sintering of the main edge seal material 30 (e.g., via laser) to form the edge seal 3. When a vacuum insulated glass panel/unit has one tempered glass substrate and one heat strengthened substrate, the substrate(s) may be tempered (e.g., thermally or chemically tempered) and heat strengthened prior to firing/sintering of the main edge seal material 30 (e.g., via laser) to form the edge seal 3.

In various example embodiments, an example vacuum insulating panel 100, still referring to Figs. 1-2, optionally may also include at least one sorption getter 8 (e.g., at least one thin film getter) for helping to maintain the vacuum in low pressure space/gap 5 by using reactive material for soaking up and/or bonding to gas molecules that remain in space/gap 5, thus providing for sorption of gas molecules in low pressure space/gap 5. The getter 8 may be provided directly on either glass substrate 1 or 2, or may be provided on a low-E coating 7 in certain example embodiments. In certain example embodiments, the getter 8 may be laser-activated and/or activated using inductive heating techniques, and/or may be positioned in a trough/recess 9 that may be formed in the supporting substrate (e.g., substrate 2) via laser etching, laser ablating, and/or mechanical drilling.

A vacuum insulating panel 100 may also include a pump-out tube 12 used for evacuating the space 5 to a pressure(s) less than atmospheric pressure, where the elongated pump-out tube 12 may be closed/sealed after evacuation of the space/gap 5. Pump-out seal 13 may be provided around tube 12, and a cap 14 may be provided over the top of the tube 12 after it is sealed. Tube 12 may extend part way through the substrate 1, for example part way through a double countersink hole drilled in the substrate as shown in Fig. 1. However, tube 12 may extend all the way through the substrate 1 in alternative example embodiments. Pump-out tube 12 may be of any suitable material, such as glass, metal, ceramic, or the like. In certain example embodiments, the pump-out tube 12 may be located on the side of the vacuum insulating panel 100 configured to face the interior of the building when the panel is used in a commercial and/or residential window. In certain example embodiments, the pump-out tube 12 may instead be located on the side of the vacuum insulating panel 100 configured to face the exterior of the building. The pump-out tube 12 may be provided in an aperture defined in either substrate 1 or 2 in various example embodiments. Pump-out seal 13 may be of any suitable material. In certain example embodiments, the pump-out seal 13 may be provided in the form of a substantially do nut- shaped pre-form which may be positioned in a recess 15 formed in a surface of the substrate 1 or 2, so as to surround an upper portion of the tube 12, so that the pre-form can be laser treated/ fired/ sintered (e.g., after formation of the edge seal 3) to provide a seal around the pump-out tube 12. Alternatively, the pump-out seal 13 may be of any suitable material and/or may be dispensed in paste and/or liquid form to surround at least part of the tube 12 and may be sealed before and/or after evacuation of space 5. The pump-out seal material 13 may be directly applied to the glass substrate material or to a primer layer applied to the glass substrate surface prior to the pump-out seal material being applied to the substrate, in certain example embodiments. After evacuation of space/gap 5, the tip of the tube 15 may be melted via laser to seal same, and hermetic sealing of the space 5 in the panel 100 can be provided both by the edge seal 3 and by the sealed upper portion of the pump-out tube 12 together with seal 13 and/or cap 14. In certain example embodiments, as shown in Fig. 1 for example, the elongated pump-out tube 12 may be substantially perpendicular (perpendicular plus/minus ten degrees, more preferably plus/minus five degrees) to the substrates 1 and 2. Any of the elements/components shown in Figs. 1-2 may be omitted in various example embodiments.

The evacuated gap/space 5 between the substrates 1 and 2, in the vacuum insulating panel 100, is at a pressure less than atmospheric pressure. For example, after the edge seal 3 has been formed, the cavity 5 evacuated to a pressure less than atmospheric pressure, and the pump-out tube 12 closed/sealed, the gap 5 between at least the substrates 1 and 2 may be at a pressure no greater than about 1.0 x 10’² Torr, more preferably no greater than about 1.0 x 10^-3 Torr, more preferably no greater than about 1.0 x 10⁴ Torr, and for example may be evacuated to a pressure no greater than about 1.0 x 10’⁶ Torr. The gap 5 may be at least partially filled with an inert gas in various example embodiments. In certain example embodiments, the evacuated vacuum gap/space 5 may have a thickness (in a direction perpendicular to planes of the substrates 1 and 2) of from about 100-1,000 pm, more preferably from about 200-500 pm, and most preferably from about 230-350 pm. Providing a vacuum in the gap/space 5 is advantageous as it reduces conduction and convection heat transport, so as to reduce temperature fluctuations inside buildings and the like, thereby reducing energy costs and needs to heat and/or cool buildings. Thus, panels 100 can provide high levels of thermal insulation.

Example low-emittance (low-E) coatings 7 which may be used in the vacuum insulating panel 100 are described in U.S. Patent Nos. 5,935,702, 6,042,934, 6,322,881, 7,314,668, 7,342,716, 7,632,571, 7,858,193, 7,910,229, 8,951,617, 9,215,760, and 10,759,693, the disclosures of which are all hereby incorporated herein by reference in their entireties. Other low-E coatings may also, or instead, be used. A low-E coating 7 typically includes at least one IR reflecting layer (e.g., of or including silver, gold, or the like) sandwiched between at least first and second dielectric layer(s) of or including materials such as silicon nitride, zinc oxide, zinc stannate, and/or the like. A low-E coating 7 may have one or more of: (i) a hemispherical emissivity/emittance of no greater than about 0.20, more preferably no greater than about 0.04, more preferably no greater than about 0.028, and most preferably no greater than about 0.015, and/or (ii) a sheet resistance (R_s) of no greater than about 15 ohms/square, more preferably no greater than about 2 ohms/square, and most preferably no greater than about 0.7 ohms/square, so as to provide for solar control. In certain example embodiments, the low-E coating 7 may be provided on the interior surface of the glass substrate to be closest to the building exterior, which is considered surface two (e.g., see Figs. 2-3), whereas in other example embodiments the low-E coating 7 may be provided on the interior surface of the glass substrate to be closest to the building interior, which is considered surface three (e.g., see Figs. 4-5). Fig. 1 illustrates an example embodiment where the edge seal 3 is spaced inwardly from the absolute edge of the panel 100, the width of the main seal layer 30 is less than a width(s) of the primer layers 31 and 32, and a thickness of the main seal layer 30 is greater than a thickness of primer layer 31 but less than a thickness of the other primer layer 32. However, the edge seal may also be provided at the absolute edge of at least one of the glass substrates in certain example embodiments, or may be provided further away from the absolute edge in certain example embodiments. Edge seal 3, which may include one or more of ceramic layers 30-32, may be located proximate the periphery or edge of the vacuum insulated panel 100 as shown in Fig. 1. Edge seal 3 may be a ceramic edge seal in certain example embodiments. In certain example embodiments, layer 30 of the edge seal may be considered a main or primary seal layer, and layers 31 and 32 may be considered primer layers of the edge seal. One or more of seal layers 30- 32, of the edge seal 3, may be of or include ceramic frit in certain example embodiments, and/or may be lead- free or substantially lead- free (e.g., no more than about 15 ppm Pb, more preferably no more than about 5 ppm Pb, even more preferably no more than about 2 ppm Pb) in certain example embodiments. In certain example embodiments, each primer layer 31 and 32 may be of a material having a coefficient of thermal expansion (CTE) that is between that of the main seal layer 30 and the closest glass substrate 1, 2. For example, referring to Figs. 1-4, primer layers 31 and 32 may each have a CTE (e.g., from about 8.0 to 8.8 x 10^-6 mm/(mm*deg. C), more preferably from about 8.3 to 8.6 x IO^-6 mm/(mm*deg. C)) which is between a CTE (e.g., from about 8.7 to 9.3 x 10’⁶ mm/(mm*deg. C), more preferably from about 8.8 to 9.2 x 10‘⁶ mm/(mm*deg. C)) of the adjacent float glass substrate 1 and a CTE (e.g., from about 7.0 to 7.9 x 10’⁶ mm/(mm*deg. C), more preferably from about 7.2 to 7.9 x 10’⁶ mm/(mm*deg. C), with an example being about 7.6 x 10’⁶ mm/(mm*deg. C)) of the main seal layer 30. The main seal layer 30 may have a CTE of at least 15% less than CTE(s) of the glass substrate(s) 1 and/or 2 in certain example embodiments. Thus, the multi-layer edge seal 3, via primer(s) 31 and/or 32, may provide for a graded CTE from the main seal 30 moving toward each glass substrate 1, 2, which provides for improved bonding of the edge seal to the glass and a more durable resulting vacuum insulating panel 100 such as capable of surviving exposure to asymmetric thermal loading and/or wind loads in the end application. The main seal layer 30, in certain example embodiments, need not contain significant amounts of CTE filler material (although it may contain significant amounts of filler in other example embodiments), which can result in an improved hermetic edge seal 3 and durability. A primer(s) 31 and/or 32 may be omitted in certain example embodiments.

In certain example embodiments, primer layers 31 and 32 may be of or include different material(s) compared to the main seal layer 30. Thus, the main seal layer 30 and primers 31 and 32 can be sintered/fired in different heating steps, in a manner which allows thermal tempering of the glass substrates 1 and 2 when sintering/heating the primers on the respective glass substrates, and which allows the main seal layer 30 to thereafter be sintered and bonded to the primers 31 and 32 via laser heating without significantly de-tempering the glass substrates 1 and 2. This advantageously results in more efficient processing, reduction in damage (e.g., micro-cracking, adhesive failure, cohesive failure, and/or significant de-tempering), and a more durable and longer lasting vacuum insulating panel with much of its temper strength retained allowing for example compliance with industry safety testing for bag impact and/or point impact fragmentation.

The edge seal 3, in certain example embodiments, may be located at an edge- deleted area (where the solar control coating 7 has been removed) of the substrate as shown in Fig. 1, so as to reduce chances of corrosion. Thus, the edge seal 3 may be positioned so that it does not overlap the low-E coating 7 in certain example embodiments. The edge seal 3 may be located at the absolute edge of the panel 100 (e.g., Fig. 1), or may be spaced inwardly from the absolute edge of the panel 100 as shown in Figs. 1-2, in different example embodiments. An outer edge of the hermetic edge seal 3 may be located within about 50 mm, more preferably within about 25 mm, and more preferably within about 15 mm, of an outer edge of at least one of the substrates 1 and/or 2. Thus, an “edge” seal does not necessarily mean that the edge seal 3 is located at the absolute edge or absolute periphery of a substrate(s) or overall panel 100. Further details of the edge seal 3, of these and other example embodiments, and regarding methods of manufacture, may be found in United States Provisional Application No. 63/540,729, filed September 27, 2023, the disclosure of which is hereby incorporated herein by reference in its entirety for all purposes.

The low-E coating 7 may be edge deleted around the periphery of the entire unit so as to remove the low-e coating material from the coated glass substrate. The low-E coating 7 edge deletion width (edge of glass to edge of low-E coating 7), in certain example embodiments, in at least one area may be from about 0-100 mm, with examples being no greater than about 6 mm, no greater than about 10 mm, no greater than about 13 mm, no greater than about 25 mm, with an example being about 16 mm. In certain example embodiments, there may be a gap between the primer seal layers 31 and 32 and/or main layer 30, and the low-E coating 7, of at least about 0.5 mm, more preferably a gap of at least about 0.5 mm, more preferably at least about 1.0 mm, so that the low-E coating 7 is not contiguous with the main seal layer 30 and/or the primer seal layers 31 and 32.

Fig. 2 is a top view of the panel 100 shown in Fig. 1. Fig. 2 further illustrates, during a process of manufacture, a laser beam 40 proceeding around the entire periphery of the panel along path 42 over the edge seal layers 30-32 to fire/sinter the main edge seal layer 30 in forming the hermetic edge seal 3. The laser beam 40 performs localized heating of the edge seal area, so as to not unduly heat certain other areas of the panel thereby reducing chances of significant de-tempering of the glass substrates. Each of these embodiments may be used in combination with any other embodiment described herein, in whole or in part. Also shown in Fig. 2 are, for example, spacers 4, getter 8, recess 9, and so forth.

Figs. 3a-3c are side cross sectional views of various example embodiments, including edge seal structure example embodiments, taken at the edge of a Fig. 1 panel 100 at Section line A - - A in Fig. 2. The example embodiments of Figs. 3a-3c illustrate example layer thicknesses, and may each be used in combination with any embodiment herein including those of Figs. 1-9. In each of the example embodiments of Figs. 3a-3c and in Fig. 1, it can be seen that main seal layer 30 may include different spaced apart layer portions and for example may include a first seal layer portion 30a comprising seal material that surrounds at least the low pressure gap 5 as viewed from above, and a second seal layer portion 30b comprising seal material that also surrounds at least the low pressure gap 5 as viewed from above. Fig. 3d is a top view of the first and second seal layer portions 30a and 30b from Figs. 1 and 3a-3c in various example embodiments, illustrating that the first and second seal layer portions 30a and 30b may be concentric and continuous as viewed from above and each may surround the low pressure space/gap 5 of the panel 100. As best shown in Fig. 3d, as viewed from above, the first continuous seal layer portion 30a also surrounds the second continuous seal layer portion 30b. As shown in Figs. 1 and 3a-3d, the first and second continuous seal layers portions 30a and 30b may be located in a common plane, and may be spaced apart from each other as viewed from above and/or cross-sectionally so that an insulating space 37 is located between at least the first and second continuous seal layer portions 30a and 30b. Insulating space 37, having a width WA as shown in Figs. 3a-3c, may be at atmospheric pressure, or at low pressure. In certain example embodiments, seal layer portions 30a and 30b do not physically contact each other at any location in the panel.

As shown in Fig. 3d, the first and second continuous seal layer portions 30a and 30b may be concentric and/or be substantially rectangular in shape as viewed from above. However, in alternative embodiments, one or both of seal layer portions 30a and/or 30b may take other shapes such as triangular, oval, circular, or the like as viewed from above. Fig. 3d also illustrates the first and second continuous seal layer portions 30a and 30b being substantially parallel to each other along each of the four sides of the panel 100 in various example embodiments, as viewed from above. Figs. 1 and 3a illustrate an example embodiment where the main seal layer 30 includes first seal layer portion 30a (having a width Wl) and second seal layer portion 30b (having a width W2), spaced apart from each other via space/gap 37 having width WA, and where both seal layer portions 30a and 30b overlap primer layer 31 and primer layer 32. In this embodiment, the main seal layer 30 has different layer portions, but the primer layers 31 and 32 do not as they are each made up of a single continuous layer. In this embodiment, the primer layers 31 and 32 each overlap and cover the gap 37. In this example embodiment, the main seal layer 30 is broken up into two distinct continuous bands 30a and 30b that surround the low pressure space/gap 5 as viewed from above (e.g., see Fig. 3d), whereas each primer layer 31 and 32 is made up of a single continuous band that surrounds the low pressure space/gap 5 as viewed from above. The seal layer portions 30a and 30b may be spaced inwardly from the edges of one or both primer layers by distances WB1 and WB2 as shown in Fig. 3a for example. One or both primer layer(s) 31 and/or 32 may have a width Wp as shown in Fig. 3a for example, which may be greater than the combined widths of the seal layer portions 30 and 30b and space 37. In certain example embodiments, primer layer 31 and primer layer 32 may be different widths, with the width of each of the primer layers 31 and 32 being greater than W1+WA+W2.

Fig. 3b is similar to the embodiment of Figs. 1 and 3a, except that the primer layer 31 is separated into two distinct spaced apart continuous bands 31a and 31b that track bands 30a and 30b, respectively, and surround the low-pressure gap/space 5 as viewed from above (e.g., see Fig. 3d). In the Fig. 3b embodiment, the main seal layer 30 includes first seal layer portion 30a (having a width Wl) and second seal layer portion 30b (having a width W2), spaced apart from each other via space/gap 37 having width WA, and where both seal layer portions 30a and 30b overlap primer layer 32. In this embodiment, first seal layer portion 30a overlaps first primer layer portion 31a, but not second primer layer portion 31b. And second seal layer portion 30b overlaps second primer layer portion 31b, but not first primer layer portion 31a. In this embodiment, the main seal layer 30 and primer layer 31 each have spaced apart different layer portions, but primer layer 32 do not as primer layer 32 is made up of a single continuous layer. In this embodiment, the primer layer 32 overlaps and covers the gap 37, but primer layer 31 does not cover and/or overlap the entire gap/space 37. In this example embodiment, the main seal layer 30 is broken up into two distinct continuous bands 30a and 30b that surround the low pressure space/gap 5 as viewed from above (e.g., see Fig. 3d), as is the primer layer 31, whereas primer layer 32 is made up of a single continuous band that surrounds the low pressure space/gap 5 as viewed from above. The seal layer portions 30a and 30b may be spaced inwardly from the edges of one or both primer layers by distances WB1 and WB2 as shown in Fig. 3b for example. Primer layer 32 may have a width Wp as shown in Fig. 3b for example, which may be greater than the combined widths of the seal layer portions 30 and 30b and space 37. In certain example embodiments, primer layer 31 and primer layer 32 may be different widths, with the width of each of the primer layers 31 and 32 being greater than W1+WA+W2.

Fig. 3c is similar to the embodiment of Figs. 1 and 3a-3b, except that both primer layers 31 and 32 are separated into two distinct spaced apart continuous bands, namely 31a and 31b for primer layer 31, and 32a and 32b for primer layer 32, that respectively track bands 30a and 30b, and surround the low-pressure gap/space 5 as viewed from above (e.g., see Fig. 3d). In the Fig. 3c embodiment, the main seal layer 30 includes first seal layer portion 30a (having a width Wl) and second seal layer portion 30b (having a width W2), spaced apart from each other via space/gap 37 having width WA. In this embodiment, first seal layer portion 30a overlaps first primer layer portion 31a and first primer layer portion 32a, but not second primer layer portions 31b and 32b. And second seal layer portion 30b overlaps second primer layer portions 31b and 32b, but not first primer layer portions 31a and 32a. In this embodiment, the main seal layer 30, primer layer 31, and primer layer 32 each have spaced apart concentric different layer portions. In this example embodiment, the main seal layer 30 is broken up into two distinct concentric continuous bands 30a and 30b that surround the low pressure space/gap 5 as viewed from above (e.g., see Fig. 3d), as are the primer layers 31 and 32. As with main seal layer portions 30a and 30b, co-planar primer layer portions 31a and 31b may be concentric and surround the low pressure space/gap 5 as viewed from above, and coplanar primer layer portions 32a and 32b may be concentric and surround the low pressure space/gap 5 as viewed from above. Primer layer portions 31a and 32a may overlap as shown in Fig. 3c, and primer layer portions 31a and 32b may overlap as shown in Fig. 3c. As with main seal layer portions 30a and 30b, primer layer portions 31a, 31b, 32a, and 32b may be substantially rectangular in shape as viewed from above, but in alternative embodiments may take other shapes such as triangular, oval, circular, or the like as viewed from above. Primer layer portions 31a and 31b (and 32a and 32b), like 30a and 30b shown in Fig. 3d, may be substantially parallel to each other along each of the four sides of the panel 100 in various example embodiments, as viewed from above.

While main seal layer 30 may be separated into two distinct spaced apart seal layer portions 30a and 30b as shown in Figs. 1 and 3a-3d, in other example embodiments it is possible to separate main seal layer 30 into three or more distinct spaced apart seal layer portions 30a, 30b, and 30c as shown in Fig. 4. Seal layer portions 30a, 30b and 30c may be concentric, substantially rectangular in shape as viewed from above, and substantially parallel to each other along sides of the panel, as in Fig. 3d, in certain example embodiments. Likewise, it is also possible to separate one or both primer layers into three or more distinct spaced apart seal layer portions.

The use of multiple seal portions (e.g., 30a and 30b) for at least main seal layer 30, as shown in Figs. 1-4 for example, provides numerous technical advantages. For example, technical advantage(s) include one or more of: (a) improved insulative properties, including edge-of-glass performance; (b) may permit use of a smaller diameter laser beam(s) and/or lower power level(s) during firing and/or sintering of the seal to reduce induced transient thermal stress and/or micro-cracking of the ceramic sealing material; (c) may permit use of a smaller laser beam(s) and/or lower power level(s) during firing and/or sintering of the seal to reduce de-tempering of glass substrate(s); (d) may permit increased laser sintering linear speed versus a single row edge seal structure via use of a smaller laser beam(s) and/or lower power level(s); (e) desirable mechanical strength to pass asymmetric thermal stress testing due to a desirable cumulative overal seal width; (f) desirable mechanical strength and structure to obtain desired fragmentation cullet size for tempered glass safety testing; and/or (g) provide desirable cross-sectional total width to improve hermiticity of the edge seal.

It has been found that adjusting the width (as viewed from above and/or in crosssection) of the main seal layer 30, of the edge seal, can be technically advantageous. For example, by making the main seal layer 30 narrower (smaller or reduced overall width, including each layer portion 30a, 30b individually, or combined), induced transient thermal stress in the layer 30 (and possibly the glass substrate) can be reduced which allows one to realize fast production times in combination with reduced chances of micro-cracking of the edge seal and/or adhesive or cohesive delamination problems. Reduced width of the main seal layer 30 can also improve U-value/U-factor performance of panel 100. The figures, for example, illustrate that the main edge seal layer 30 has a width less than the width of one or both of the adjacent primer layers 31 and 32. For example, referring to Fig. 3a for example, the width “Wl” of seal layer portion 30a is less than the width Wp of primer layer 32 and the width of the primer layer 31, the width “W2” of seal layer portion 30b is less than the width Wp of primer layer 32 and the width of the primer layer 31, the combined width W1+W2 is less than the width Wp of primer layer 32 and the width of the primer layer 31, and the combined width W1+W2+WA is less than the width Wp of primer layer 32 and the width of the primer layer 31. As another example, referring to Fig. 3b for example, the width “Wl” of seal layer portion 30a is less than the width Wp of primer layer 32 and the width of the primer layer portion 31a, the width “W2” of seal layer portion 30b is less than the width Wp of primer layer 32 and the width of the primer layer 31b, the combined width W1+W2 is less than the width Wp of primer layer 32 and the width of the combined width of primer layer portions 31a and 31b, and the combined width W1+W2+WA is less than the width Wp of primer layer 32 and the combined width of the primer layer portions 31a and 31b.

Adjusting the width (as viewed from above and/or in cross-section) of one or both of the primer layers 31 and/or 32 may be technically advantageous in certain example embodiments. For example, see the width “Wp” of the primer layer 32 in Fig. 3b; primer layer 31 may have a width similar to the width Wp of primer layer 32 in certain example embodiments. When the primer layers 31 and 32 are too narrow (e.g., Wp is too small), defects such as fish scales, glass micro-cracking, or the like, may occur in the final product which can lead to seal failures and/or a non-durable product. Thus, by making one or both of the primer layers 31 and/or 32 wider, induced transient thermal stress, defects and seal failures can be reduced. Wider primer layers allow more heat to be dissipated during the laser sintering/firing process of the main seal layer 30, thereby resulting in less glass substrate and seal layer defects, and less de-tempering of the glass substrate(s). In certain example embodiments, for example, the main edge seal layer 30 may have a width “W” (e.g., W1+ W2 in Figs. 3a-3c) which is less than the width (e.g., “Wp”) of at least one of the adjacent primer layers 31 and/or 32. In an example embodiment, the width “W” (e.g., W1+ W2 in Figs. 3a-3c) of the main seal layer 30 may be about 6 mm and the width of the primer layers 31 and 32 may be about 10 mm, so that the width of one or both of the primer layers is greater than the width of the main seal layer. For example, in the manufactured vacuum insulating panel 100, the main seal layer 30 of the edge seal 3 may have an average width “W” (e.g., W1+ W2 in Figs. 3a- 3c) of from about 2-20 mm, more preferably from about 4-10 mm, more preferably from about 3-9 mm or from about 4-8 mm, still more preferably from about 5-7 mm, and with an example main seal layer 30 average width being about 6 mm; and/or one or both of the primer layers 31 and 32 may have an average width Wp of from about 2-20 mm, more preferably from about 6-14 mm, more preferably from about 8-12 mm, still more preferably from about 9-11 mm, and with an example primer average width being about 10 mm. In certain example embodiments, the respective width(s) of each layer 30, 31, and 32 may be substantially the same (the same plus/minus 10%, more preferably plus/minus 5%) along the length of the edge seal 3 around the periphery of the entire panel 100. In certain example embodiments, the ratio Wp/W of the width Wp of one or both primer layers 31, 32 to the width W of the main seal layer 30 may be from about 1.2 to 2.2, more preferably from about 1.4 to 1.9, and most preferably from about 1.5 to 1.8 (e.g., the ratio Wp/W is 1.67 when a primer layer 31 and/or 32 is 10 mm wide and the main seal layer 30 is 6 mm wide: 10/6 = 1.67). In certain example embodiments, one or both primer layers 31 and/or 32 is/are at least about 1 mm wider, more preferably at least about 2 mm wider, and most preferably at least about 3 mm wider, than the main seal layer 30 at one or more locations around the periphery of the panel 100 and possibly around the entire periphery of the panel. These desirable widths for ceramic seal layers 30-32 in the panel 100 may be appropriate when using the materials for seal layers 30-32 discussed herein, and may be adjusted in an appropriate manner if different seal materials are instead used which is possible in certain example embodiments. Other widths for one or more of seal layers 30-32, not discussed herein, may be used in various other example embodiments.

In certain example embodiments, as viewed from above and/or in cross-section as shown in Figs. 3a-3c for example, the lateral edge(s) of seal layer portion 30a and/or 30b of the main seal layer 30 may be spaced inwardly an offset distance (e.g., WB1 and/or WB2) from the respective lateral edges of the primer seal layer 31 and/or the primer seal layer 32 on each side of the main seal layer. In certain example embodiments, the offset distance (e.g., WB1 and/or WB2) on one or both sides of the main seal layer 30 may be from about 0.5 to 6.0 mm, more preferably from about 0.5 to 3.0 mm, more preferably from about 0.5 to 2.5 mm, more preferably from about 1.0 to 2.5 mm, and most preferably from about 1.5 to 2.5 mm, with an example being about 2.0 mm on each side, although the offset distance may be different on the left and right sides of the main seal layer. In certain example embodiments, the offset distance on one or both sides of the main seal layer 30 may be at least about 0.5 mm, more preferably at least about 1.0 mm, and most preferably at least about 1.5 mm.

In certain example embodiments, in the manufactured vacuum insulating panel 100, the main seal layer 30 of the edge seal 3 may have an average thickness of from about 30-180 pm, more preferably from about 30-120 pm, more preferably from about 40-100 pm, and most preferably from about 50-85 pm, with an example main seal layer 30 average thickness being from about 60-80 pm. In certain example embodiments, in the manufactured vacuum insulating panel 100, the primer layer 31 of the edge seal 3 may have an average thickness of from about 10-100 pm, more preferably from about 10- 80 pm, more preferably from about 20-70 pm, and most preferably from about 20-55 pm, with an example primer layer 31 average thickness being about 45 pm. In certain example embodiments, in the manufactured vacuum insulating panel 100, the primer layer 32 (opposite the side from which the laser beam 40 is directed) of the edge seal 3 may have an average thickness of from about 80-240 pm, more preferably from about 100-220 pm, more preferably from about 120-200 pm, and most preferably from about 120-170 pm, with an example primer layer 32 average thickness being about 145 pm. In certain example embodiments, the thickness of the main seal layer 30 may be at least about 30 pm thinner (more preferably at least about 45 pm thinner) than the thickness of the primer seal layer 32, and may be at least about 10 pm thicker (more preferably at least about 20 pm, and more preferably at least about 30 pm thicker) than the thickness of the primer seal layer 31. In certain example embodiments, in the manufactured vacuum insulating panel 100, the overall average thickness of the edge seal 3 may be from about 150-330 pm, more preferably from about 200-310 pm, and most preferably from about 220-290 pm, with an example overall edge seal 3 average thickness being about 270 pm. In certain example embodiments, the respective thicknesses of each layer 30, 31, and 32 may be substantially the same (the same plus/minus 10%, more preferably plus/minus 5%) along the length of the edge seal 3 around the periphery of the entire panel 100. In certain example embodiments, in the manufactured vacuum insulating panel 100, the ratio TM/TPI of the thickness TM of the main seal layer 30 to the thickness Tpi of thin primer layer 31 may be from about 1.2 to 2.2, more preferably from about 1.4 to 2.0, and most preferably from about 1.5 to 1.9 (e.g., the ratio TM/TPI is 1.78 when a primer layer 31 is 45 pm thick and the main seal layer 30 is 80 pm thick as shown in Fig. 9: 80/45 = 1.78). In certain example embodiments, in the manufactured vacuum insulating panel 100, the ratio TM/TP2 of the thickness TM of the main seal layer 30 to the thickness TP2 of the primer layer 32 may be from about 0.25 to 0.90, more preferably from about 0.40 to 0.75, and most preferably from about 0.45 to 0.65 (e.g., the ratio TM/TP2 is 0.55 when a primer layer 32 is 145 pm thick and the main seal layer 30 is 80 pm thick as shown in Fig. 9: 80/145 = 0.55). In certain example embodiments, in the manufactured vacuum insulating panel 100, the ratio TM/TS of the thickness TM of the main seal layer 30 to the total thickness Ts of the overall edge seal 3 may be from about 0.15 to 0.60, more preferably from about 0.20 to 0.50, and most preferably from about 0.25 to 0.35 (e.g., the ratio TM/TS is 0.30 when the overall seal 3 is 270 pm thick and the main seal layer 30 is 80 pm thick as shown in Fig. 9: 80/270 = 0.30). These thicknesses for ceramic seal layers 30-32 in the panel 100 may be appropriate when using the materials for seal layers 30-32 discussed herein, and may be adjusted in an appropriate manner such as if different seal materials are instead used which is possible in certain example embodiments. Other thicknesses for layers 30-32, not discussed herein, may be used in various other example embodiments.

In certain embodiments, the main layer 30 may be a double row (e.g., see Figs. 1 and 3a-3d) with each row having a width between about 1 mm to about 6 mm with a preferred width of about 3 mm. The primer layer(s) 31 and/or 32 width may range from about 4 mm to 16 mm with an example width of 10 mm, in certain example embodiments. An example design for a double row, moving laterally, may be 10 mm primer width comprising 1 mm no main layer width WB 1 , 3 mm main layer 30 width Wl, 2 mm no main layer width WA, 3 mm main layer width W2, and 1 mm no main layer width WB2 (e.g., see Fig. 3a). An alternative example design for a double row may be a 12 mm primer width comprising a 2 mm no main layer, 3-mm main layer width Wl, 2 mm no main layer width WA, 3 mm main layer width W2, and 2 mm no main layer width WB2. An alternative example design for a double row may be a 12 mm primer width comprising a 1 mm no main layer, 3 mm main layer, 4 mm no main layer, 3 mm main layer and 1 mm no main layer.

In certain embodiments, the main layer 30 may be a triple row (e.g., see Fig. 4), for example with each row having a width between about 1 mm to about 6 mm with an example width of about 2 mm. The primer layer(s) 31 and/or 32 width (e.g., Wp) may be between about 4 mm to 16 mm with an example width Wp of about 10 mm. An example design, moving laterally, for a triple row may be a 12 mm primer width comprising 1 mm no main layer width WB1, 2 mm main layer width Wl, 2 mm no main layer width WAI, 2 mm main layer width W2, 2 mm no main layer width WA2, 2 mm main layer width W3, and 1 mm no main layer width WB2 (e.g., see Fig. 4). An alternative example design for a triple row may be a 14 mm primer width comprising 2 mm no main layer, 2 mm main layer, 2 mm no main layer, 2 mm main layer and 1 mm no main layer.

In various example embodiments, a double row design (e.g., see Figs. 1 and 3a-3d) may include, for example, two rows each about 3 mm in width with a gap between the two rows for a total width of about 8 mm. The laser beam spot may, for example, range between about 25% and about 100% larger than the width of the combined double row main layer 30 and the laser power may be adjusted accordingly to allow reduced irradiation time for a given spot in the main layer 30. An example laser beam diameter may be from about 4-15 mm. The area of the laser beam at maximum temperature for sintering of the main seal may be approximately about 85% of the laser beam diameter or about 10 mm, in an example embodiment. In certain example embodiments, the laser beam spot may, for example, range between about 25% and about 100% larger than the width of each individual row main layer 30 and/or the laser power may be adjusted accordingly to allow reduced irradiation time for a given spot in the main layer 30. An example laser beam diameter may be from about 2-10 mm. The area of the laser beam at maximum or high temperature for sintering of the main seal may be approximately 85% of the laser beam diameter or about 5 mm, in an example embodiment.

Figs. 5-6 and 8 illustrate an example material(s) that may be used for the main seal layer 30, including seal layer portions 30a, 30b, and/or 30c, in various example embodiments, including for example in any of the embodiments of Figs. 1-9. However, other suitable materials (vanadium oxide based ceramic materials with little or no Te oxide, solder glass, or the like) may instead be used for layer 30 in various example embodiments. Fig. 5 is a table/graph showing weight % and mol % of various compounds/elements in an example main seal 30 material, prior to sintering of layer 30, according to an example embodiment (measured via non-carbon detecting XRF). And Fig. 6 is a table/graph showing weight % and mol % of various compounds/elements in an example main seal 30 material, including seal layer portions 30a, 30b, and/or 30c, according to an example embodiment (measured via carbon detecting XRF), before and after laser treatment/sintering of the main seal layer 30 for edge seal formation. And the left side of Fig. 8 sets forth a table/graph showing an elemental analysis (non-oxide analysis) of weight % and mol % of various elements in an example main seal 30 material, before and after laser treatment for edge seal formation.

Table 1 A sets forth example ranges for various elements and/or compounds for this example tellurium (Te) oxide based main seal 30 material according to various example embodiments, for both mol % and weight %, prior to firing/sintering thereof and thus prior to hermetic edge seal 3 formation. In certain example embodiments, the main seal layer 30 may comprise mol% and/or wt.% of the following compounds in one or more of the following orders of magnitude: tellurium oxide > vanadium oxide > aluminum oxide, tellurium oxide > vanadium oxide > silicon oxide, tellurium oxide > vanadium oxide > aluminum oxide > magnesium oxide, and/or tellurium oxide > vanadium oxide > silicon oxide > magnesium oxide, before and/or after firing/sintering of the layer 30. It will be appreciated that other materials may be used together, or in place of, those shown below, and that the example percentages may be different in alternate embodiments.

TABLE 1 A (example material for main seal layer 30 prior to firing/sintering)

Tellurium Vanadate based and/or inclusive glasses (including tellurium oxide and vanadium oxide), such as those in Table 1 A, in certain example embodiments are ideally suited for the main seal functionality when utilizing laser irradiation for the firing/sintering of the main seal layer 30. The base main seal material may comprise tellurium oxide (e.g., a combination of TeCh, TeCh+i, and TeCU) and vanadium oxide (e.g., a combination of V2O5, VO2, and V2O3) per the weight % and/or mol % described in Table 1 A. In certain example embodiments, it may be desirable to have a higher amount of tellurium oxide compared to vanadium oxide, in order to increase the material density in the sintered state and thus improve hermiticity of the seal. With respect to main seal material(s) in Table 1 A for the main seal layer 30, the Te oxide (e.g., one or more of TeCU, TeCL, TeOs+i, and/or other stoichiometry(ies) involving Te and O) and V oxide (e.g., one or more of VO2, V2O5, V2O3, and/or other stoichiometry(ies) involving V and O) in the material may be made up of about the following stoichiometries before/after sintering as shown below in Table IB (tellurium oxide stoichiometries prior to firing/sintering), Table 1C (tellurium oxide stoichiometries after firing/sintering), Table ID (vanadium oxide stoichiometries prior to firing/sintering), Table IE (vanadium oxide stoichiometries after firing/sintering), respectively, measured via XPS.

TABLE IB (example stoichiometries of Te oxide in material for main seal layer 30 prior to laser firing/sintering)

TABLE 1C (example stoichiometries of Te oxide in material for main seal layer 30 after laser firing/sintering)

TABLE ID (example stoichiometries of V oxide in material for main seal layer 30 prior to laser firing/sintering)

TABLE IE (example stoichiometries of V oxide in material for main seal layer 30 after laser firin g/sintering)

For example, the “Example” column in Table IB indicates that 57% of the Te present in the material prior to sintering/firing was in an oxidation state of TeCU, 42% of the Te present in the material prior to sintering/firing was in an oxidation state of TeCh, and 1 % of the Te present in the material prior to sintering/firing was in an oxidation state of TeCh+i. And the “Example” column in Table 1C indicates that after the laser firing/sintering of the main seal layer 30 just 14% of the Te present in the main seal layer 30 material was in an oxidation state of TeCU, but 81% of the Te present in the material was in an oxidation state of TeCh, and 5% of the Te present in the material prior to sintering/firing was in an oxidation state of TeCh+i. Accordingly, in certain example embodiments, it will be appreciated that the laser firing/sintering of the main seal layer 30 may cause much of the TeCU to transform/convert into TeCh and TeCh+i, which is advantageous because it increases the material’s absorption in the near infrared (e.g., 808 or 810 nm for example, which may be used for the laser during sintering/firing) which provides for increased heating efficiency and reducing the chances of significantly detempering the glass substrate(s) due to improved heating efficiency during the firing/sintering.

In certain example embodiments, prior to firing/sintering, the material for the main seal layer 30 may include tellurium oxide with the following stoichiometry/oxidation state ratio(s) in terms of what oxidation state(s) are used by the Te in the material (e.g., see Table IB): TeCU > TeCE > TeCh+i. But the laser sintering/firing of the main seal layer may then cause the Te stoichiometry ratios/states to change to the following during/after sintering/firing: TeCE > TeCU > TeCh+i, which is advantageous in vacuum insulating panels as discussed above. The TeCU is a trigonal bipyramid structure, TeCh is a trigonal pyramid structure, and TeCh+i is a polyhedral structure. In certain example embodiments, due to optimized laser treatment for firing/sintering of the main seal layer as discussed herein, the TeCU largely converts to TeCU and marginally to TeCU+i with increasing temperature with a concurrent increase in the number of Te=O sites resulting from cleavage within the network structure.

For example, the “Example” column in Table ID indicates that 84% of the V present in the material prior to sintering/firing was in an oxidation state of V2O5, 15% of the V present in the material prior to sintering/firing was in an oxidation state of VO2, and 1% of the V present in the material prior to sintering/firing was in an oxidation state of V2O3. And the “Example” column in Table IE indicates that after the laser firing/sintering of the main seal layer just 25% of the V present in the main seal layer 30 material was in an oxidation state of V2O5, but 63% of the V present in the material was in an oxidation state of VO2, and 12% of the V present in the material prior to sintering/firing was in an oxidation state of V2O3. The other columns in Tables IB- IE represent the same, with different values as shown. Accordingly, in certain example embodiments, it will be appreciated that the laser firing/sintering of the main seal layer 30 may cause much of the V2O5 to transform/convert into VO2 and V2O3, which is advantageous because it increases the material’s density and thus the hermiticity and durability of the seal (e.g., VO2 results in a more dense layer than does V2O5). In certain example embodiments, it is desirable to reduce the V2O5 content in the final sintered/fired state of the main seal 30 because the glass network becomes more closed with decreasing V2O5 concentration, e.g., due to the reduction of non-bridging oxygen resulting in a higher density seal which improves water/moisture resistance, mechanical strength (adhesive and cohesive), and/or hermeticity. The Tg of the main seal 30 material may also slightly increase with a reduction in V2O5. Thus, from Tables 1B-1E and Fig. 6, it will be appreciated that in certain example embodiments a type of laser processing (e.g., 808 or 810 nm continuous wave laser) may be used to sinter/fire the main seal layer 30 in a manner that causes one or more, or any combination, of the following to occur during and/or as a result of the sintering/firing: (a) stoichiometry values/oxidation states of Te in the layer to change from TeCF > TeOs > TeCh+i prior to laser firing/sintering, to TeCh > TeC > TeCh+i following laser firing/sintering of the layer 30; (b) stoichiometry values/oxidation states of Te in the layer to change from TeOi > TeCh prior to laser firing/sintering, to TeCf > TeCh following laser firing/sintering of the layer 30; (c) stoichiometry values/oxidation states of vanadium (V) in the layer to change from V2O5 > VO2 > V2O3 prior to laser firing/sintering, to VO2 > V2O5 > V2O3 after laser firing/sintering of the layer 30; (d) stoichiometry values/oxidation states of V in the layer to change from V2O5 > VO2 prior to laser firing/sintering, to VO2 > V2O5 after laser firing/sintering of the layer 30; (e) the ratio TeO4:TeO3 to change from about 1.0 to 2.0 (more preferably from about 1.2 to 1.6, more preferably from about 1.3 to 1.5) prior to sintering/firing to from about 0.05 to 0.40 (more preferably from about 0.10 to 0.30, more preferably from about 0.13 to 0.22) after the laser sintering/firing of the layer 30; (f) the ratio V2Os:VO2 to change from about 1.0 to 10.0 (more preferably from about 3.0 to 8.0, more preferably from about 4.5 to 7.0, with an example being 84:15 = 5.66) prior to sintering/firing to from about 0.10 to 0.90 (more preferably from about 0.20 to 0.80, more preferably from about 0.25 to 0.50, with an example being 25:63 = 0.39) after the laser sintering/firing of the layer 30; (g) a binding energy shift of the Te peak of at least about 0.15 eV, more preferably of at least about 0.20 eV, and most preferably of at least about 0.25 or 0.30 eV; and/or (h) a binding energy shift of the V peak of at least about 0.10 eV, more preferably of at least about 0.15 eV.

This main seal material(s), or substantially the same material, may also be used for the pump-out tube seal 13, with or without a primer, in certain example embodiments, although other types of seals may also be used such as vanadium oxide based ceramic sealing glass or solder glass. Other compounds may also be provided in this main seal 30 material, including but not limited to, on a weight and/or mol basis, for example one or more of: 0-15% (more preferably 1-10%) tungsten oxide; 0-15% (more preferably 1- 10%) molybdenum oxide; 0-60% (or 38-52%) zinc oxide; 0-15% (more preferably 0- 10%) copper oxide, and/or other elements shown in the figures.

Table 2 sets forth example ranges for various elements and/or compounds for this example tellurium oxide-based material for main seal layer 30 according to various example embodiments, for both mol % and weight %, after firing/sintering thereof and thus after hermetic edge seal 3 formation. It will be appreciated that other materials may be used together, or in place of, those shown below, and that the example percentages may be different in alternate embodiments.

TABLE 2 (example material for main seal layer 30 after laser firing/sintering)

In certain example embodiments, the material for the main seal layer 30 may include filler. The filler may, for example, comprise one or more of zirconyl phosphates, dizirconium diorthophosphates, zirconium tungstates, zirconium vanadates, aluminum phosphate, cordierite, eucryptite, ekanite, alkaline earth zirconium phosphates such as (Mg, Ca, Ba, Sr) Zr₄ P₅0 24, either alone or in combination. Filler in a range of 20-25 wt. % may be used in layer 30 in certain example embodiments. Main seal layer 30, and/or the primer layer(s) 31 and/or 32, is/are lead- free and/or substantially lead- free in certain example embodiments.

Table 3 sets forth example ranges for various elements for this example tellurium oxide based main seal 30 material according to various example embodiments, using elemental analysis (non-oxide analysis) for both mol % and weight %, prior to firing/sintering thereof and thus prior to hermetic edge seal 3 formation. Fig. 8 also provides an elemental analysis for various example seal materials, including for Te oxide based main seal and/or pump-out tube seal layers 30 and 13. In certain example embodiments, the main seal layer 30 and/or the pump-out seal layer 13 may comprise mol% and/or wt.% of the following elements in one or more of the following orders of magnitude: Te > V > Al, Te > V > Si, Te > V > Al > Mg, Te > O > V, Te > O > V > Al, and/or Te > V > Si > Mg, before and/or after firing/sintering of the layer. It will be appreciated that other materials may be used together, or in place of, those shown below, and that the example percentages may be different in alternate embodiments. The elemental Te/V ratio in the main seal layer 30 and/or seal layer 13, after sintering/firing and in terms of weight %, may be from about 1.5:1 to 5:1, more preferably from about 2:1 to 4:1, and most preferably from about 2.5:1 to 3.5:1. The elemental Te/Al ratio in the main seal layer 30 and/or seal layer 13, after firing/sintering thereof and in terms of weight %, may be from about 5:1 to 35:1, more preferably from about 8:1 to 20:1, and most preferably from about 9:1 to 15:1. The elemental Si/Mg ratio in the main seal layer 30 and/or seal layer 13, after firing/sintering thereof and in terms of weight %, may be from about 1:1 to 35:1, more preferably from about 2:1 to 10:1, and most preferably from about 3: 1 to 7: 1. It has been found that one or more of these ratios is technically advantageous for achieving desirable melting points, softening points, and/or thermal diffusivity.

TABLE 3 (elemental analysis - example main seal 30 material prior to firing/sintering)

This material may also be used for the pump-out seal 13, with or without a primer, in certain example embodiments, although other types of seals may also be used such as vanadium oxide based ceramic sealing glass or solder glass. Other compounds may also be provided in this material (e.g., see Fig. 8).

Table 4 sets forth example ranges for various elements for this example tellurium oxide based main seal 30 material according to various example embodiments, using elemental analysis (non-oxide analysis) for both mol % and weight %, after firing/sintering thereof and thus after formation of the hermetic edge seal 3 (e.g., see also Fig. 8). It will be appreciated that other materials may be used together, or in place of, those shown below, and that the example percentages may be different in alternate embodiments.

TABLE 4 (elemental analysis - example main seal 30 material after firing/sintering)

This material may also be used for the pump-out seal 13, with or without a primer, in certain example embodiments, although other types of seals may also be used such as vanadium oxide based ceramic sealing glass or solder glass. Other compounds may also be provided in this material (e.g., see Fig. 14).

Figs. 7-8 illustrate an example material(s) that may be used for the primer layer(s) 31 and/or 32 in various example embodiments, including for example in any of the embodiments of Figs. 1-9. Primer layer 31, if applicable, includes primer layer portions 31a and 31b; and primer layer 32, if applicable, includes primer layer portions 32a and 32b. However, other suitable materials, such as solder glass, other materials comprising bismuth oxide, and so forth, may be used for one or both primer layers 31 and/or 32 in various example embodiments. Fig. 7a is a table/graph showing weight % and mol % of various compounds/elements in a primer seal 31 and/or 32 material according to an example embodiment (measured via carbon detecting XRF), before and after laser treatment for edge seal formation, which primer material may be used in combination with any embodiment herein (e.g., for one or both primer layers); Fig. 7b is a table/graph showing weight % and mol % of various compounds/elements in a primer seal material according to an example embodiment (measured via fused bead XRF), before and after substrate tempering and laser firing of the main seal layer, which primer material may be used in combination with any embodiment herein (e.g., for one or both primer layers) including those of Figs. 1-9; and the right side of Fig. 8 sets forth a table/graph showing an elemental analysis (non-oxide analysis) of weight % and mol % of various elements in an example primer material, before and after laser treatment for edge seal formation.

Table 5 sets forth example ranges for various elements and/or compounds for this example primer material, for one or both layers 31 and/or 32, according to various example embodiments, for both mol % and weight %, prior to firing/sintering. In certain example embodiments, one or both of the primer layers 31 and/or 32 may comprise mol% and/or wt.% of the following compounds in one or more of the following orders of magnitude: boron oxide > bismuth oxide > silicon oxide, bismuth oxide > silicon oxide > boron, boron oxide > bismuth oxide > silicon oxide > titanium oxide, bismuth oxide > silicon oxide > boron oxide > titanium oxide, boron oxide > silicon oxide > titanium oxide > bismuth oxide, and/or silicon oxide > boron oxide > bismuth oxide, before and/or after formation of the hermetic edge seal 3. It will be appreciated that other materials may be used together, or in place of, those shown below, and that the example percentages may be different in alternate embodiments.

TABLE 5 (example primer material prior to firing/sintering)

It is noted that “stoichiometry” as used herein covers, for example, oxygen coordination and oxygen state. Other compounds may also be provided in the primer material (e.g., see Figs. 7-8). For example, on a weight basis, the primer material for one or both layers 31 and/or 32 may further comprise one or more of: 0-20% (or 1-7%) zinc oxide; 0-15% (or 2-7%) aluminum oxide; 0-10% (or 0-5%) magnesium oxide; 0-10% (or 0-5%) chromium oxide; 0-10% (or 0-5%) iron oxide; 0-20% (or 1 -8%) sodium oxide; carbon dioxide; and/or other elements shown in the figures (e.g., see Figs. 7a-7b).

Table 6 sets forth example ranges for various elements and/or compounds for this example primer layer 31 and/or 32 material according to various example embodiments, for both mol % and weight %, after firing/ sintering thereof and after hermetic edge seal 3 formation. It will be appreciated that other materials may be used together, or in place of, those shown below, and that the example percentages may be different in alternate embodiments.

TABLE 6 (example primer material after edge seal formation)

Other compounds may also be provided in this primer material, as discussed above and/or shown in the figures. Certain elements may change during firing/sintering, and certain elements may at least partially burn off during processing prior to formation of the final edges seal 3. It will be appreciated that, as with other layers discussed herein, other materials may be used together, or in place of, those shown above and/or below, and that the example weight/mol percentages may be different in alternate embodiments. The ceramic sealing glass primer materials for layer(s) 31 and/or 32 are lead-free and/or substantially lead-free in certain example embodiments.

Table 7 sets forth example ranges for various elements for the example primer material according to various example embodiments, using elemental analysis (non-oxide analysis) for both mol % and weight %, after firing/sintering thereof and thus after hermetic edge seal 3 formation. Fig. 8 also provides an elemental analysis for various example seal materials, including the primer material at the right side thereof. In certain example embodiments, one or both of primer layers 31 and/or 32 may comprise mol% of the following elements in one or more of the following orders of magnitude: B > Bi, O > B > Bi, O > B > C, O > B > Si > Bi, and/or B > Si > Bi > Ti, before and/or after firing/sintering of the layer and formation of the edge seal 3 (e.g., see also Fig. 8). It will be appreciated that other materials may be used together, or in place of, those shown below, and that the example percentages may be different in alternate embodiments. TABLE 7 (elemental analysis - example primer material after firing/sintering and after edge seal formation)

The primer materials in Figs. 7-8 and Table 7 may be considered to be boron- based, given that excluding oxygen, silicon, and carbon, boron has the largest magnitude in terms of mol% before and/or after firing/sintering. While other materials (e.g., bismuth based primers, solder glass, etc.) may be used for layer(s) 31 and/or 32 in certain example embodiments, boron-based material such as in Figs. 7-8 and Table 7 may be desirable for use as primer layer(s) 31 and/or 32 in certain example embodiments, for example when laser heating is used for sintering/firing the main seal layer 30, as follows. In certain example embodiments, on an elemental basis (not including oxides) and in terms of mol%, primer layer(s) 31 and/or 32 may have a ratio B/Bi, of boron (B) to bismuth (Bi), of from about 1.1 to 10.0, more preferably from about 2.0 to 6.0, and most preferably from about 2.5 to 4.5 (with an example being about 3.7), after firing/sintering of the main seal layer 30 and/or primer(s). In certain example embodiments, in terms of mol% after sintering/firing of layer 30, primer layer(s) 31 and/or 32 may comprise at least two times as much B as Bi, more preferably at least about three times as much B as Bi, and/or may comprise at least about two time as much B oxide as Bi oxide, more preferably at least about three, four, or five times as much B oxide as Bi oxide. Such a primer (e.g., 31) is thus able to allow sufficient near-IR energy from the laser (e.g., at 808 or 810 nm) to pass so that the main seal layer 30 can be efficiently and quickly fired/sintered, without significantly de-tempering glass and/or inducing significant transient thermal stress.

In certain example embodiments, main seal layer 30, after edge seal formation (e.g., via laser sintering), may have a density of at least about 2.75 g/cm³, more preferably of at least about 2.80 g/cm³, more preferably of at least about 2.90 g/cm³, more preferably of at least about 3.00 g/cm³, even more preferably of at least about 3.10 g/cm³, and most preferably of at least about 3.20 g/cm³. In certain example embodiments, the main seal layer 30, after edge seal formation (e.g., via laser sintering), may have a density of from about 2.80-4.00 g/cm³, more preferably from about 2.90-3.90 g/cm³, and most preferably from about 3.10-3.70 g/cm³ or 3.15-3.40 g/cm³. In certain example embodiments, these main seal layer 30 density ranges, preferably with a substantially lead-free ceramic material, may be in combination with a maximum processing temperature of the main seal layer 30 (e.g., during sintering and formation of the edge seal) during edge seal formation of no more than about 520 degrees C, more preferably no more than about 500 degrees C, and most preferably no greater than about 480 degrees C. For example, the main seal layer 30 may be of or include a material characterized by the above density ranges, after being processed at about 405 degrees C for about 15 minutes. As explained above, such high densities advantageously provide for less porosity, good water resistance, good mechanical adhesion strength, and good hermiticity for the edge seal.

In certain example embodiments, one or both primer layer(s) 31 and/or 32 may have, after edge seal formation (e.g., via laser sintering), a density of at least about 2.75 g/cm³, more preferably of at least about 3.20 g/cm³, more preferably of at least about 3.40 g/cm³, more preferably of at least about 3.50 g/cm³, even more preferably of at least about 3.60 g/cm³. In certain example embodiments, one or both primer layers may have a density higher than the density of the main seal layer 30. The high density of the primer layer(s) is advantageous for improving hermiticity of the overall edge seal. In certain example embodiments, primer layer 31 and/or primer layer 32 may have a density of from about 3.0-4.2 g/cm³, more preferably from about 3.3-4.0 g/cm³, more preferably from about 3.5-3.8 g/cm³, more preferably from about 3.6-3.7 g/cm³. In certain example embodiments, primer layer 31 and/or primer layer 32 may have a density of at least about 0.20 g/cm³ higher (more preferably at least about 0.30 higher, more preferably at least about 0.40 higher) than a density of the main seal layer 30. For example, the main seal layer 30 may have a density of about 3.22 g/cm³ and the primer layers 31 and 32 may each have a density of about 3.66 g/cm³.

Fig. 9 is a flowchart illustrating example steps in making a vacuum insulating panel according to various example embodiments, which may be used in combination with any embodiment herein. Steps 201-204 apply to one of the two substrates, while steps 205-209 apply to the other one of the substrates, and steps 210-213 apply when the substrates are mated to each other via clamping, sealing, and/or the like.

A substrate (e.g., substrate 1 in Fig. 1) is provided in step 201, and another substrate (e.g., substrate 2 in Fig. 1) is provided in step 205. The substrate in step 205 may have a low-E coating 7 provided thereon, which may be edge-deleted in step 206. A primer layer (e.g., 31 in Fig. 1) may be applied to the corresponding substrate (e.g., substrate 1 in Fig. 1) in step 202, whereas the other primer layer (e.g., 32 in Fig. 1) may be applied to the other substrate (e.g., substrate 2 in Fig. 1) in step 207. In various example embodiments, one or both ceramic sealing glass primer layers 31-32 may be boron oxide inclusive and/or bismuth oxide inclusive or other suitable material, and may be applied using silk screen printing, digital printing, pad printing, extrusion coating, ceramic spray coating or nozzle dispense methods. The primer layer(s) 31 and/or 32 may be deposited to achieve a sintered width of about 10 mm around the periphery of the substrates in certain example instances. The substrates, with respective primers thereon, may then be thermally heated to remove solvents in the material using one of the following substrate heating methods or a combination thereof: radiation, convection, induction, microwave or conduction. The substrates may be heated between 100 degrees C to 250 degrees C for 30 seconds to ten minutes to remove the solvents from the sealing glass material with an example temperature being 180 degrees C for about 4 minutes. Substrates may then be thermally heated to remove organic resin materials in the sealing glass primer material using one of the following substrate heating methods or a combination thereof; radiation, convection, induction, microwave or conduction, such as for example to from 275 degrees C to 400 degrees C for 30 seconds to ten minutes with an example temperature being about 320 degrees C for 6 minutes. The removal of the organic resin material from the primers may be referred to as ceramic sealing glass binder burnout. In steps 203 and 208, the substrates may then be thermally heated for thermally tempering the glass substrates and to sinter and fire the ceramic primer material to the desired physical thickness and material properties using one of the following substrate heating methods or a combination thereof: radiation, convection, induction, microwave or conduction. For example, the substrates 1 and 2 may be heated to from between 575 degrees C to 700 degrees C for 30 seconds to five minutes depending on the thickness of the substrates with an example temperature being 625 degrees C at a rate of 30 seconds per mm of uncoated glass thickness and 60 second per mm of Low-E coated glass thickness. Thus, the primer layers 31-32 are fired/sintered when the corresponding glass substrates 1 and 2 are thermally tempered, in certain example embodiments, in steps 203 and 208. When heat strengthened glass is used instead of tempered glass, in certain example embodiments, the primer layers 31 and/or 32 may be sintered in a step that does not involve tempering.

In certain example embodiments, in steps 203 and 208, the primer layers 31 and 32 may bond to and/or diffuse into the respective glass substrates upon which they are located since the glass substrates 1, 2 are above the glass softening point, and create a high adhesion strength to the glass substrates. Interdiffusion of the primer layer(s) into the respective glass substrate(s) results in a high adhesion strength to the glass substrates, as for example SiO in the primer layer(s) bond to a silicon-rich layer in a soda lime silicate float glass in certain example embodiments. For example, adhesion strength using lap shear mechanical test methods may be from about 60-120 kg per cm², which is higher than the modulus of rupture of soda lime silicate glass substrates. The primer layers may have a high degree of hermeticity, e.g., less than 1 x 10⁸ cc/m²/day of vacuum loss, low moisture vapor transmission rates, and/or provide high levels of mechanical adhesion to the glass substrates, in certain example embodiments.

In step 204, the ceramic sealing glass main layer 30 (e.g., which may be Te oxide based or inclusive, or other suitable material) may then applied to one of the glass substrates over the primer layer (e.g., over primer 31, and/or over primer 32), such as via silkscreen printing, ceramic spray, extrusion coating, digital printing, pad printing, nozzle dispense or other commercially available ceramic sealing material application methods. The layer 30 may have tellurium oxide as a material with the highest weight percentage and vanadium oxide as a material with the second highest weight percentage, in certain example embodiments. The main seal layer 30 may then be thermally dried to remove solvents in the sealing glass matrix. The substrate may be thermally heated to remove solvents in the material using one of the following substrate heating methods or a combination thereof: radiation, convection, induction, microwave and/or conduction.

After the spacers are provided on a substrate in step 209, the two glass substrates 1 and 2 may then be mated together and clamped around the periphery of the vacuum insulated unit to create a mated unit in step 210. The pump-out tube 12 and preform 13 may be applied to the substrate having recess 15 between steps 210 and 211 in certain example embodiments. The mated unit may then be thermally heated to burn out the resin binders that provide the carrier vehicle for the sealing glass paste material and then pre-glazed at a temperature of about 370 degrees C to impart mechanical strength properties and performance between the main layer and primer layer(s). For example, the perimeter of the vacuum insulated glass unit may be physically clamped with a controlled pressure to assist in setting the final thickness/height of the edge seal 3. The substrates may then be thermally heated to remove organic resin materials in the main sealing glass material 30 using one of the following substrate heating methods or a combination thereof; radiation, convection, induction, microwave or conduction. The binder burnout duration may be optimized so that much or substantially all binder is removed from the main layer 30 and the target density and/or porosity may be achieved. The mated unit may be heated between 250 degrees C to 350 degrees C for 30 seconds to twenty minutes with an example material temperature of 320 degrees C and a duration of 8 minutes, in certain example embodiments; and/or heated between 340 degrees C to 390 degrees C for 30 seconds to ten minutes with an example material temperature of 370 degrees C and a duration of 8 minutes. The mated unit may be heated to about 370 degrees C to pre-glaze the main layer 30 in certain example embodiments. The pre-glaze may one or more of:

(1) create a strong mechanical bond between the primer layer(s) and the main seal layer;

(2) the main seal layer may reach or substantially reach its target thickness so the mechanical clamps may be removed prior to laser sintering; and/or (3) reduce process requirements for the laser to enable high linear rates.

In step 211, the mated unit may then be pre-heated to an ambient temperature of about 320 degrees C (e.g., see pre-heating discussion above). The mated unit can be preheated using radiation, convection and/or conduction for example, with an example being a precision hot plate incorporating convective heating to achieve desired thermal uniformity across the substrate surfaces. The mated pair may be heated to 320 degrees C to minimize or reduce the thermal delta between the glass substrate temperature and the sintering/melting point of the main seal layer 30 (e.g., which may be from about 390 degrees C to 410 degrees C) in certain example embodiments, so as to reduce transient thermal stress in the sealing glass materials. For example, transient thermal stress may be about 50 MPa without pre-heating to raise the ambient substrate temperature versus less than 10 MPa with pre-heating the glass substrates to about 320 degrees C.

In step 212, a laser (e.g., an 800 nm, 808 nm, 810 nm, or 940 nm continuous wave laser) 41 may then be used to locally and selectively sinter/fire the main seal layer 30. For example, the laser 41 and/or laser beam 40 may move around the periphery of the vacuum insulated unit using an XYZ gantry robot at a defined linear rate to wet the interface between the fully sintered primer layers 31, 32 and the pre-glazed main seal layer 30, sinter the main seal layer 30 to its final state (e.g., thickness, density and porosity) and to melt or partially melt the material to reduce the size of air pores in the main seal layer 30 and/or at the main layer to primer interface. The laser linear speed, laser power, laser beam size, laser irradiation time, and/or laser thermal decay time may be optimized to achieve desired physical, chemical and/or mechanical properties. The seal 13 around the pump-out tube 12 may be laser sintered/fired using the same or a different laser. In various example embodiments, a continuous wave 808-nm or 810-nm laser may be used to one or more of: (1) wet the surface or interface between the thin primer layer 31 and main seal layer 30 and the thick primer layer 32 and the main seal layer 30 to achieve for example a target 40 kg/cm² mechanical adhesion; (2) locally sinter/fire the main seal layer 30 to densify material; and/or (3) locally melt the main layer material to fill in air voids/pores at the main seal layer 30 to primer layer(s) interface(s) that were generated during the main seal layer application process. While any type of laser may be used in various embodiments for sintering layer 30, a continuous wave laser may be preferred over a scanning/rastering laser scanning lasers may involve multiple pulses at a given irradiation spot resulting in a series of heating and cooling events that can increase transient stress and raise the final residual stress, which could result in micro-cracks that result in no or poor hermeticity.

In step 213, the space/gap 5 of the vacuum insulating panel is then evacuated to a low pressure using the pump-out tube 12, the tube closed off, and a cap 14 may be applied thereto.

In an example embodiment, there may be provided a vacuum insulating panel (e.g., 100) comprising: a first substrate (e.g., 1 or 2); a second substrate (e.g., 1 or 2); a plurality of spacers (e.g., 4) provided in a gap (e.g., 5) between at least the first and second substrates, wherein the gap (e.g., 5) is at pressure less than atmospheric pressure; a seal (e.g., 3) provided at least partially between at least the first and second substrates, the seal comprising a first seal layer (e.g., 30); and wherein the first seal layer (e.g., 30) comprises a first continuous seal layer portion (e.g., 30a) comprising seal material that surrounds at least the gap (e.g., 5) as viewed from above, and a second continuous seal layer portion (e.g., 30b) comprising seal material that also surrounds at least the gap as viewed from above, wherein the first and second continuous seal layer portions (e.g., 30a and 30b) are spaced apart from each other as viewed from above so that a space (e.g., 37) is located between at least the first and second continuous seal layer portions.

In the vacuum insulating panel of the immediately preceding paragraph, the first and second continuous seal layer portions may be concentric as viewed from above.

In the vacuum insulating panel of any of the preceding two paragraphs, the first and second continuous seal layer portions may be substantially rectangular in shape as viewed from above.

In the vacuum insulating panel of any of the preceding three paragraphs, the first continuous seal layer portion may surround the second continuous seal layer portion as viewed from above.

In the vacuum insulating panel of any of the preceding four paragraphs, the first and second continuous seal layer portions may be in a common plane.

In the vacuum insulating panel of any of the preceding five paragraphs, the first and second continuous seal layer portions may be substantially parallel to each other along at least part of at least one side of the panel.

In the vacuum insulating panel of any of the preceding six paragraphs, the first and second continuous seal layer portions may each comprise from about 40-70 wt.% tellurium oxide.

In the vacuum insulating panel of any of the preceding seven paragraphs, the first and second continuous seal layer portions may each comprise tellurium oxide and vanadium oxide, and by wt.% comprise more tellurium oxide than vanadium oxide. In the vacuum insulating panel of any of the preceding eight paragraphs, from about 60-95% of Te in each of the first and second continuous seal layer portions may be in a form of TeCh, and from about 3-35% of Te in each of the first and second continuous seal layer portions may be in a form of TeC . Tellurium oxide of the first seal layer may further comprise TeCh+i, and wherein each of the first and second continuous seal layer portions may comprise more TeCh than TeCh+i by wt.%. A ratio TeO^TeCh in each of the first and second continuous seal layer portions may be from about 0.05 to 0.40.

In the vacuum insulating panel of any of the preceding nine paragraphs, the first seal layer may comprise vanadium oxide which may comprise VO2 and V2O5, and wherein more V in each of the first and second continuous seal layer portions may be in a form of VO2 than V2O5. From about 35-85% of V in each of the first and second continuous seal layer portions may be in a form of VO2. From about 50-75% of V in each of the first and second continuous seal layer portions may be in a form of VO2. From about 5-45% of V in the each of the first and second continuous seal layer portions may be in a form of V2O5. The vanadium oxide may further comprise V2O3, and wherein more V in each of the first and second continuous seal layer portions may be in a form of VO2 than V2O3.

In the vacuum insulating panel of any of the preceding ten paragraphs, the seal may further comprise a second seal layer (e.g., primer layer) overlapping at least one of the first and second continuous seal layer portions. The second seal layer may comprise from about 30-60 mol% boron oxide; and/or may comprise from about 1-20 mol% bismuth oxide and from about 20-65 mol% boron oxide and comprises at least two times more boron oxide than bismuth oxide in terms of mol%. The second seal layer may comprise more boron oxide than bismuth oxide in terms of wt.%.

In the vacuum insulating panel of any of the preceding eleven paragraphs, the first seal layer may have a density of from about 2.8-4.0 g/cm³, and/or the second seal layer may have a density of from about 3.0-4.2 g/cm³, and wherein the density of the second seal layer may be at least about 0.20 g/cm³ greater than the density of the first seal layer.

In the vacuum insulating panel of any of the preceding twelve paragraphs, the first seal layer may be a main seal layer, and the second seal layer may be a primer layer. The second seal layer may comprise a first continuous seal layer primer portion that surrounds at least the gap as viewed from above, and a second continuous seal layer primer portion that also surrounds at least the gap as viewed from above, wherein the first and second continuous seal layer primer portions may be spaced apart from each other as viewed from above so that a space may be located between at least the first and second continuous seal layer primer portions.

In the vacuum insulating panel of any of the preceding thirteen paragraphs, the seal may further comprise a third seal layer (e.g., primer layer) overlapping at least one of the first and second continuous seal layer portions. The third seal layer may comprise from about 1-20 mol% bismuth oxide and/or from about 20-65 mol% boron oxide, and may comprise at least two times more boron oxide than bismuth oxide in terms of mol%. For at least one location of the seal, the first seal layer may have a first thickness, the second seal layer may have a second thickness, and the third seal layer may have a third thickness; and wherein the first thickness may be greater than the second thickness and less than the third thickness. For at least one location of the seal, a width of the first seal layer may be less than a width of the second seal layer by at least about 1 mm.

In the vacuum insulating panel of any of the preceding fourteen paragraphs, the seal may be substantially lead-free.

In the vacuum insulating panel of any of the preceding fifteen paragraphs, the first and second substrates may comprise glass substrates. In the vacuum insulating panel of any of the preceding sixteen paragraphs, the first and second substrates may comprise tempered glass substrates or heat strengthened glass substrates.

In the vacuum insulating panel of any of the preceding seventeen paragraphs, the seal may be a hermetic edge seal of the vacuum insulating panel.

In the vacuum insulating panel of any of the preceding eighteen paragraphs, the panel may be configured for use in a window.

It is to be understood that a singular form of a noun corresponding to an item may include one or more of the things, unless the relevant context clearly indicates otherwise. As used herein, "A or B", "at least one of A and B", "at least one of A or B", "A, B or C", "at least one of A, B and C", and "A, B, or C," each of which may include any one of the items listed together in the corresponding one of the phrases, or all possible combinations thereof. Terms such as “first”, “second”, or “first” or “second” may simply be used to distinguish the component from other components in question, and do not limit the components in other aspects (e.g., importance or order). Terms, such as “first”, “second”, and the like, may be used herein to describe various components. Each of these terminologies is not used to define an essence, order or sequence of a corresponding component but used merely to distinguish the corresponding component from other component(s). For example, a "first" component may be referred to as a "second" component, and similarly, the "second" component may be referred to as the "first" component. “Or” as used herein may cover both “and” and “or.”

It should be noted that if it is described that one component is "connected", "coupled", or "joined" to another component, at least a third component(s) may be "connected", "coupled", and "joined" between the first and second components, although the first component may be directly connected, coupled, or joined to the second component. Thus, terms such as “connected” and “coupled” cover both direct and indirectly connections and couplings. The singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises/comprising" and/or "includes/including" when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or populations thereof.

The word “about” as used herein means the identified value plus/minus 5%.

“On” as used herein covers both directly on, and indirectly on with intervening element(s) therebetween. Thus, for example, if element A is stated to be “on” element B, this covers element A being directly and/or indirectly on element B. Likewise, “supported by” as used herein covers both in physical contact with, and indirectly supported by with intervening element(s) therebetween.

Each embodiment herein may be used in combination with any other embodiment(s) described herein.

While the disclosure has been illustrated and described with reference to various example embodiments, it will be understood that the various embodiments are intended to be illustrative, not limiting. It will further be understood by those skilled in the art that various changes in form and detail may be made without departing from the true spirit and full scope of the disclosure, including the appended claims and their equivalents. It will also be understood that any of the embodiment(s) described herein may be used in combination with any other embodiment(s) described herein.

Claims

CLAIMS A vacuum insulating panel comprising: a first substrate; a second substrate; a plurality of spacers provided in a gap between at least the first and second substrates, wherein the gap is at pressure less than atmospheric pressure; a seal provided at least partially between at least the first and second substrates, the seal comprising a first seal layer; and wherein the first seal layer comprises a first continuous seal layer portion comprising seal material that surrounds at least the gap as viewed from above, and a second continuous seal layer portion comprising seal material that also surrounds at least the gap as viewed from above, wherein the first and second continuous seal layer portions are spaced apart from each other as viewed from above so that a space is located between at least the first and second continuous seal layer portions. The vacuum insulating panel of claim 1, wherein the first and second continuous seal layer portions are concentric as viewed from above. The vacuum insulating panel of any preceding claim, wherein the first and second continuous seal layer portions are substantially rectangular in shape as viewed from above. The vacuum insulating panel of any preceding claim, wherein the first continuous seal layer portion surrounds the second continuous seal layer portion as viewed from above. The vacuum insulating panel of any preceding claim, wherein the first and second continuous seal layer portions are in a common plane. The vacuum insulating panel of any preceding claim, wherein the first and second continuous seal layer portions are substantially parallel to each other along at least part of at least one side of the panel. The vacuum insulating panel of any preceding claim, wherein the first and second continuous seal layer portions each comprise from about 40-70 wt.% tellurium oxide. The vacuum insulating panel of any preceding claim, wherein the first and second continuous seal layer portions each comprise tellurium oxide and vanadium oxide, and by wt.% comprise more tellurium oxide than vanadium oxide. The vacuum insulating panel of any preceding claim, wherein from about 60- 95% of Te in each of the first and second continuous seal layer portions is in a form of TeCh, and from about 3-35% of Te in each of the first and second continuous seal layer portions in a form of TeCU. The vacuum insulating panel of claim 9, wherein the tellurium oxide further comprises TeCh+i, and wherein each of the first and second continuous seal layer portions comprise more TeCh than TeCh+i by wt.%. The vacuum insulating panel of any preceding claim, wherein a ratio TeO4:TeO3 in each of the first and second continuous seal layer portions is from about 0.05 to 0.40. The vacuum insulating panel of any preceding claim, wherein vanadium oxide in the first and second seal layer portions comprises VO2 and V2O5, and wherein more V in each of the first and second continuous seal layer portions is in a form of VO2 than V2O5. The vacuum insulating panel of any preceding claim, wherein from about 35- 85% of V in each of the first and second continuous seal layer portions is in a form of VO2. The vacuum insulating panel of any preceding claim, wherein from about SOTS % of V in each of the first and second continuous seal layer portions is in a form of VO2. The vacuum insulating panel of any preceding claim, wherein from about 5- 45% of V in the each of the first and second continuous seal layer portions is in a form of V2O5. The vacuum insulating panel of claim 15, wherein the vanadium oxide further comprises V2O3, and wherein more V in each of the first and second continuous seal layer portions is in a form of VO2 than V2O3. The vacuum insulating panel of any preceding claim, wherein the seal further comprises a second seal layer overlapping at least one of the first and second continuous seal layer portions. The vacuum insulating panel of claim 17, wherein the second seal layer comprises from about 30-60 mol% boron oxide. The vacuum insulating panel of any of claims 17-18, wherein the second seal layer comprises boron oxide and bismuth oxide, wherein the second seal layer comprises from about 1-20 mol% bismuth oxide and from about 20-65 mol% boron oxide, and comprises at least two times more boron oxide than bismuth oxide in terms of mol%. The vacuum insulating panel of any of claims 17-19, wherein the second seal layer comprises more boron oxide than bismuth oxide in terms of wt.%. The vacuum insulating panel of any of claims 17-20, wherein the first seal layer has a density of from about 2.8-4.0 g/cm³, the second seal layer has a density of from about 3.0-4.2 g/cm³, and wherein the density of the second seal layer is at least about 0.20 g/cm³ greater than the density of the first seal layer. The vacuum insulating panel of any of claims 17-21, wherein the first seal layer is a main seal layer, and the second seal layer is a primer layer. The vacuum insulating panel of any of claims 17-22, wherein the second seal layer comprises a first continuous seal layer primer portion that surrounds at least the gap as viewed from above, and a second continuous seal layer primer portion that also surrounds at least the gap as viewed from above, wherein the first and second continuous seal layer primer portions are spaced apart from each other as viewed from above so that a space is located between at least the first and second continuous seal layer primer portions. The vacuum insulating panel of any of claims 17-23, wherein the seal further comprises a third seal layer overlapping at least one of the first and second continuous seal layer portions. The vacuum insulating panel of claim 24, wherein the third seal layer comprises from about 1-20 mol% bismuth oxide and from about 20-65 mol% boron oxide, and comprises at least two times more boron oxide than bismuth oxide in terms of mol%. The vacuum insulating panel of any of claims 24-25, wherein for at least one location of the seal, the first seal layer has a first thickness, the second seal layer has a second thickness, and the third seal layer has a third thickness; and wherein the first thickness is greater than the second thickness and less than the third thickness. The vacuum insulating panel of any of claims 17-26, wherein, for al least one location of the seal, a width of the first seal layer is less than a width of the second seal layer by at least about 1 mm. The vacuum insulating panel of any preceding claim, wherein the seal is substantially lead-free. The vacuum insulating panel of any preceding claim, wherein the first and second seal layer portions do not physically contact each other at any location in the panel. The vacuum insulating panel of any preceding claim, wherein the first and second substrates comprise glass substrates. The vacuum insulating panel of any preceding claim, wherein the first and second substrates comprise tempered glass substrates or heat strengthened glass substrates. The vacuum insulating panel of any preceding claim, wherein the seal is a hermetic edge seal of the vacuum insulating panel. The vacuum insulating panel of any preceding claim, wherein the panel is configured for use in a window. A vacuum insulating panel comprising: a first glass substrate; a second glass substrate; a plurality of spacers provided in a gap between at least the first and second glass substrates, wherein the gap is at pressure less than atmospheric pressure; a seal provided al least partially between al least the first and second substrates, the seal comprising a first seal layer; wherein the first seal layer comprises first and second substantially coplanar spaced apart seal layer portions each comprising seal material, wherein the first and second substantially coplanar seal layer portions are spaced apart from each other so that a space is located between at least the first and second seal layer portions, and wherein the second seal layer portion is located between at least first seal layer portion and the gap at pressure less than atmospheric pressure. The vacuum insulating panel of claim 34, wherein the first and second seal layer portions are concentric as viewed from above. The vacuum insulating panel of any of claims 34-35, wherein the first and second seal layer portions are continuous and substantially rectangular in shape as viewed from above. The vacuum insulating panel of any of claims 34-36, wherein the first seal layer portion surrounds the second seal layer portion and surrounds the gap at pressure less than atmospheric pressure, as viewed from above. The vacuum insulating panel of any of claims 34-37, wherein the first and second seal layer portions are substantially parallel to each other along at least part of at least one side of the panel. The vacuum insulating panel of any of claims 34-38, wherein the first and second seal layer portions each comprise from about 40-70 wt.% tellurium oxide. The vacuum insulating panel of any of claims 34-39, wherein the first and second seal layer portions each comprise tellurium oxide and vanadium oxide, and by wt.% comprise more tellurium oxide than vanadium oxide. The vacuum insulating panel of any of claims 34-40, wherein from about 60- 95% of Te in each of the first and second seal layer portions is in a form of TeCh, and from about 3-35% of Te in each of the first and second continuous seal layer portions in a form of TeC The vacuum insulating panel of any of claims 34-41, wherein the seal further comprises a second seal layer and/or a third seal layer, the second seal layer and/or the third seal layer overlapping at least one of the first and second seal layer portions. The vacuum insulating panel of claim 42, wherein the second seal layer and/or the third seal layer comprises from about 30-60 mol% boron oxide. The vacuum insulating panel of any of claims 42-43, wherein the second seal layer and/or the third seal layer comprises from about 1-20 mol% bismuth oxide and from about 20-65 mol% boron oxide, and comprises at least two times more boron oxide than bismuth oxide in terms of mol%. The vacuum insulating panel of any of claims 34-44, wherein the first and second seal layer portions do not physically contact each other at any location in the panel. The vacuum insulating panel of any of claims 34-45, wherein the seal further comprises a second seal layer having a width, as viewed cross-sectionally and/or from above, greater than a combined width of a width of the first seal layer portion, a width of the second seal layer portion, and a width of the space between at least the first and second seal layer portions

M. A vacuum insulating panel comprising: a first glass substrate; a second glass substrate; a plurality of spacers provided in a gap between at least the first and second glass substrates, wherein the gap is at pressure less than atmospheric pressure; a seal provided at least partially between at least the first and second substrates, the seal comprising a first seal layer and a second seal layer; wherein the first seal layer comprises first and second substantially coplanar spaced apart seal layer portions each comprising seal material, wherein the first and second substantially coplanar seal layer portions are spaced apart from each other so that a space is located between at least the first and second seal layer portions, wherein the second seal layer portion is located between at least first seal layer portion and the gap at pressure less than atmospheric pressure; and wherein the second seal layer comprises a width, as viewed cross- sectionally and/or from above, greater than a combined width of a width of the first seal layer portion, a width of the second seal layer portion, and a width of the space between at least the first and second seal layer portions.