Vacuum insulated panel with seal material for improved density, glass therefor, and method of making same

Glass for making a high density seal layer of a vacuum insulating panel, the glass comprising:

• tellurium oxide
• from about 25-75 wt. %
• vanadium oxide
• from about 15-40 wt. %
• bismuth oxide
• from about 10-40 wt. %
• aluminum oxide
• from about 0-10 wt. %
• zinc oxide
• from about 0-10 wt. %
• wherein tellurium oxide has the largest wt. % of any metal oxide in the glass, and in terms of wt. % a ratio tellurium oxide/bismuth oxide in the glass is from about 1.1 to 2.9.

A composite material for making a high density seal layer of a vacuum insulating panel, the composite material comprising:

• tellurium oxide
• from about 20-70 wt. %
• vanadium oxide
• from about 5-50 wt. %
• bismuth oxide
• from about 9-26 wt. %
• aluminum oxide
• from about 3-20 wt. %
• silicon oxide
• from about 5-25 wt. %
• zinc oxide
• from about 0-10 wt. %
• wherein tellurium oxide has the largest wt. % of any metal oxide in the composite material, in terms of wt. % a ratio tellurium oxide/bismuth oxide in the composite material is from about 1.1 to 2.9.

A method of making 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, the gap at pressure less than atmospheric pressure, and a seal comprising a first seal layer;

• the method comprising:
• providing a composite material including a glass and a filler, the glass comprising:
• tellurium oxide
• from about 25-75 wt. %
• vanadium oxide
• from about 15-40 wt. %
• bismuth oxide
• from about 10-35 wt. %
• aluminum oxide
• from about 0-10 wt. %
• zinc oxide
• from about 0-10 wt. %
• wherein tellurium oxide has the largest wt. % of any metal oxide in the glass;
• heating the composite material to form the first seal layer so that the first seal layer has a density of at least 3.50 g/cm3;
• and
• evacuating the gap to pressure less than atmospheric pressure.

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;
• wherein the first seal layer comprises, in terms of wt. %:
• tellurium oxide
• from about 20-70%
• bismuth oxide
• from about 8-30%
• wherein tellurium oxide has the largest wt. % of any metal oxide in the first seal layer, and the first seal layer has a density of at least 3.55 g/cm3.

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 comprising, in terms of wt. %:
• tellurium oxide
• from about 20-70%
• bismuth oxide
• from about 8-30%
• wherein tellurium oxide has the largest wt. % of any metal oxide in the seal, and the seal has a density of at least 3.55 g/cm3.