Vacuum insulated panel with edge seal
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-layer edge seal structure, including at least one layer including boron oxide (e.g., B 2 O 3 or any other stoichiometry).
1 . 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 a second seal layer which at least partially overlap each other; and
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 as much boron oxide as bismuth oxide in terms of mol %, and wherein the second seal layer comprises elements in the following order of magnitude on an elemental basis: B>Si>Bi>Ti.
2 . The vacuum insulating panel of claim 1 , wherein the second seal layer comprises from about 30-60 mol % boron oxide.
3 . The vacuum insulating panel of claim 2 , wherein the second seal layer comprises from about 1-12 mol % bismuth oxide and from about 0-50 mol % silicon oxide.
4 . The vacuum insulating panel of claim 3 , wherein the second seal layer comprises from about 40-55 mol % boron oxide.
5 . The vacuum insulating panel of claim 3 , wherein the second seal layer comprises from about 0-20 mol % titanium oxide.
6 . The vacuum insulating panel of claim 1 , wherein the second seal layer comprises at least three times as much boron oxide as bismuth oxide in terms of mol %.
7 . The vacuum insulating panel of claim 1 , wherein the second seal layer comprises at least four times as much boron oxide as bismuth oxide in terms of mol %.
8 . The vacuum insulating panel of claim 1 , wherein the second seal layer comprises more boron oxide than bismuth oxide in terms of wt. %.
9 . The vacuum insulating panel of claim 1 , wherein the second seal layer has an average particle size (D50) of from about 2-15 μm.
10 . The vacuum insulating panel of claim 1 , wherein the second seal layer has an average particle size (D50) of from about 3-8 μm.
11 . The vacuum insulating panel of claim 1 , wherein the second seal layer comprises elements in the following order of magnitude on an elemental basis: O>B>Si>Bi.
12 . The vacuum insulating panel of claim 1 , wherein a thermal conductivity of the second seal layer is greater than a thermal conductivity of the first seal layer.
13 . The vacuum insulating panel of claim 12 , wherein the second seal layer has a thermal conductivity of from 1.0 to 1.90 W/mK, and the first seal layer has a thermal conductivity of from 0.80 to 1.00 W/mK.
14 . The vacuum insulating panel of claim 12 , wherein the second seal layer has a thermal conductivity of from about 1.10 to 1.50 W/mK, and the first seal layer has a thermal conductivity of from about 0.80 to 0.95 W/mK.
15 . The vacuum insulating panel of claim 1 , wherein the first seal layer has a density of from about 2.8-4.0 g/cm 3 , the second seal layer has a density of from about 3.0-4.2 g/cm 3 , and wherein the density of the second seal layer is at least about 0.20 g/cm 3 greater than the density of the first seal layer.
16 . The vacuum insulating panel of claim 1 , wherein the second seal layer has a bridging oxygen (BO) content of at least about 80%.
17 . The vacuum insulating panel of claim 1 , wherein the second seal layer has a bridging oxygen (BO) content of at least about 85%.
18 . The vacuum insulating panel of claim 1 , wherein the second seal layer has a bridging oxygen (BO) content of at least about 89%.
19 . The vacuum insulating panel of claim 1 , wherein the first seal layer comprises tellurium oxide and vanadium oxide, and by wt. % comprises more tellurium oxide than vanadium oxide.
20 . The vacuum insulating panel of claim 1 , wherein the first seal layer comprises from about 40-70 wt. % tellurium oxide.
21 . The vacuum insulating panel of claim 20 , wherein from about 60-95% of Te in the first seal layer is in a form of TeO 3 , and from about 3-35% of Te in the first seal layer is in a form of TeO 4 .
22 . The vacuum insulating panel of claim 21 , wherein the tellurium oxide further comprises TeO 3+1 , and wherein the first seal layer comprises more TeO 3 than TeO 3+1 by wt. %.
23 . The vacuum insulating panel of claim 22 , wherein from about 1-44% of Te in the first seal layer is in a form of TeO 3+1 .
24 . The vacuum insulating panel of claim 20 , wherein a ratio TeO 4 :TeO 3 in the first seal layer is from about 0.05 to 0.40.
25 . The vacuum insulating panel of claim 19 , wherein the vanadium oxide comprises VO 2 and V 2 O 5 , and wherein more V in the first seal layer is in a form of VO 2 than V 2 O 5 .
26 . The vacuum insulating panel of claim 25 , wherein from about 35-85% of the V in the first seal layer is in a form of VO 2 .
27 . The vacuum insulating panel of claim 25 , wherein from about 50-75% of the V in the first seal layer is in a form of VO 2 .
28 . The vacuum insulating panel of claim 27 , wherein from about 5-45% of the V in the first seal layer is in a form of V 2 O 5 .
29 . The vacuum insulating panel of claim 25 , wherein the vanadium oxide further comprises V 2 O 3 , and wherein more V in the first seal layer is in a form of VO 2 than V 2 O 3 .
30 . The vacuum insulating panel of claim 1 , wherein the first seal layer is a main seal layer, and the second seal layer is a primer layer.
31 . The vacuum insulating panel of claim 1 , wherein the seal further comprises a third seal layer, the first seal layer being located between at least the second and third seal layers, and wherein the third seal layer comprises boron oxide and bismuth oxide, 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 as much boron oxide as bismuth oxide in terms of mol %.
32 . The vacuum insulating panel of claim 31 , 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.
33 . The vacuum insulating panel of claim 1 , wherein, for at 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.
34 . The vacuum insulating panel of claim 1 , wherein the seal is substantially lead-free.
35 . The vacuum insulating panel of claim 1 , wherein the first seal layer has a physical thickness of from about 40-100 μm.
36 . The vacuum insulating panel of claim 35 , wherein the second seal layer has a physical thickness of from about 20-70 μm or from about 100-220 μm.
37 . The vacuum insulating panel of claim 1 , wherein, for the at least one location of the seal, a thickness of the first seal layer is at least about 10 μm thicker than a thickness of the second seal layer.
38 . The vacuum insulating panel of claim 1 , the second seal layer has a melting point (Tm) at least 100 degrees C. higher than a melting point of the first seal layer.
39 . The vacuum insulating panel of claim 1 , the second seal layer has a melting point (Tm) at least 150 degrees C. higher than a melting point of the first seal layer.
40 . The vacuum insulating panel of claim 1 , wherein the first and second substrates comprise glass substrates.
41 . The vacuum insulating panel of claim 1 , wherein the first and second substrates comprise tempered glass substrates or heat strengthened glass substrates.
42 . The vacuum insulating panel of claim 1 , wherein the seal is a hermetic edge seal of the vacuum insulating panel.
43 . The vacuum insulating panel of claim 1 , wherein the panel is configured for use in a window.
44 . A vacuum insulating panel comprising:
a first substrate;
a second substrate;
at least one spacer 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 a second seal layer which at least partially overlap each other;
wherein the second seal layer comprises boron oxide and bismuth oxide, wherein the second seal layer comprises at least two times as much boron oxide as bismuth oxide in terms of mol %;
wherein the second seal layer comprises, in terms of mol %, from about 4-9% bismuth oxide, from about 40-55% boron oxide, from about 15-35% silicon oxide, and from about 3-12% titanium oxide.
45 . 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 a second seal layer;
wherein the second seal layer comprises boron oxide and bismuth oxide, wherein the second seal layer comprises at least four times as much boron oxide as bismuth oxide in terms of mol %, and
wherein the second seal layer comprises from about 1-12 mol % bismuth oxide, at least about 45 mol % boron oxide, and from about 15-35 mol % silicon oxide.
46 . The vacuum insulating panel of claim 45 , wherein the second seal layer comprises from about 20-65 mol % boron oxide.
47 . The vacuum insulating panel of claim 45 , wherein the second seal layer comprises, in terms of mol %, from about 15-35% silicon oxide.
48 . The vacuum insulating panel of claim 45 , wherein the first seal layer comprises from about 40-70 wt. % tellurium oxide.
49 . The vacuum insulating panel of claim 45 , wherein the first seal layer comprises from about 40-70 wt. % tellurium oxide, and the tellurium oxide comprises more TeO 3 than TeO 4 .
50 . The vacuum insulating panel of claim 45 , wherein the second seal layer comprises elements in the following order of magnitude on an elemental basis: B>Si>Bi.
51 . The vacuum insulating panel of claim 45 , wherein the first seal layer is a main seal layer, and the second seal layer is a primer layer.
52 . The vacuum insulating panel of claim 45 , wherein the seal further comprises a third seal layer, the first seal layer being located between at least the second and third seal layers, and wherein the third seal layer comprises boron oxide and bismuth oxide and comprises at least four times more boron oxide than bismuth oxide in terms of mol %.
53 . The vacuum insulating panel of claim 45 , the second seal layer has a melting point (Tm) at least 100 degrees C. higher than a melting point of the first seal layer.
54 . The vacuum insulating panel of claim 45 , wherein the first and second substrates comprise tempered glass substrates or heat strengthened glass substrates.
55 . 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 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, a second seal layer, and a third seal layer, wherein the first seal layer is at least partially located between at least the second and third seal layers;
wherein the first seal layer comprises from about 20-80 wt. % tellurium oxide, the tellurium oxide comprising TeO 4 and TeO 3 , and wherein the first seal layer comprises more TeO 3 than TeO 4 by wt. %; and
wherein the second and third seal layers each comprise from about 20-65 mol. % boron oxide and a bridging oxygen (BO) content of at least about 80%.