Glass panel unit and glass window
A glass panel unit includes: a sealing member arranged between a first panel and a second panel, which are arranged to face each other with a predetermined gap left between themselves, to hermetically bond the first panel and the second panel together; and an internal space sealed hermetically with the first panel, the second panel, and the sealing member. The glass panel unit further includes a spacer arranged in the internal space so as to be in contact with the first panel and the second panel. The spacer includes a plurality of resin layers that are stacked one on top of another in a direction in which the first panel and the second panel face each other. At least any two of the plurality of resin layers have different elastic moduli.
1. A glass panel unit comprising
a first panel including at least a first glass pane;
a second panel arranged to face the first panel with a predetermined gap left with respect to the first panel and including at least a second glass pane;
a sealing member arranged between the first panel and the second panel to hermetically bond the first panel and the second panel together;
an internal space configured to form a reduced-pressure space by being sealed hermetically with the first panel, the second panel, and the sealing member; and
a spacer arranged in the internal space so as to be in contact with the first panel and the second panel,
the spacer including a plurality of resin layers that are stacked one on top of another in a facing direction in which the first panel and the second panel face each other, at least any two of the plurality of resin layers having different elastic moduli, and
one resin layer, having the smallest elastic modulus, out of the plurality of resin layers having a greater visible light transmittance than any other of the plurality of resin layers.
2. The glass panel unit of claim 1 , wherein
the plurality of resin layers includes three or more resin layers, and
the spacer is symmetric with respect to a plane that passes through a midpoint between the first panel and the second panel in the facing direction and that is perpendicular to the facing direction.
3. The glass panel unit of claim 1 , wherein
the plurality of resin layers includes three or more resin layers, and
two resin layers, which are in contact with the first panel and the second panel, respectively, out of the three or more resin layers have a greater elastic modulus than at least one other resin layer, which is in contact with neither the first panel nor the second panel, out of the three or more resin layers.
4. The glass panel unit of claim 1 , wherein
each of the plurality of resin layers has one of two elastic moduli, and at least one resin layer, having the smaller one of the two elastic moduli, out of the plurality of resin layers has a greater overall thickness than at least one other resin layer, having the larger one of the two elastic moduli, out of the plurality of resin layers.
5. The glass panel unit of claim 1 , further comprising:
a third panel arranged opposite from the first panel so as to face the second panel;
a second sealing member arranged between the second panel and the third panel to hermetically bond the second panel and the third panel together; and
a second internal space sealed hermetically with the second panel, the third panel, and the second sealing member and enclosing a dry gas airtightly.
6. A glass window comprising:
the glass panel unit of claim 1 ; and
a window frame fitted onto a peripheral portion of the glass panel unit.