Glass panel unit manufacturing method, building component manufacturing method, glass panel unit manufacturing system, and glass panel unit
A glass panel unit manufacturing method includes a bonding step, a pressure reducing step, and a sealing step. The bonding step includes bonding together a first substrate and a second substrate with a first sealant to create an inner space. The pressure reducing step includes producing a reduced pressure in the inner space through an exhaust port that the first substrate has. The sealing step includes irradiating a second sealant, inserted into the exhaust port, with an infrared ray through a region, where a low emissivity film is nonexistent, of the second substrate.
1. A glass panel unit manufacturing method comprising:
an arrangement step of stacking a first substrate, including a glass pane, and a second substrate, including a glass pane, one upon the other with a first sealant in a frame shape interposed between the first substrate and the second substrate;
a bonding step of bonding together the first substrate and the second substrate with the first sealant to create an inner space surrounded with the first sealant between the first substrate and the second substrate;
a pressure reducing step of producing a reduced pressure in the inner space through an exhaust port that the first substrate has; and
a sealing step of sealing the exhaust port up while maintaining the reduced pressure in the inner space,
the sealing step including irradiating, with a low emissivity film facing the inner space, a second sealant, inserted into the exhaust port, with an infrared ray to locally heat the second sealant and seal the exhaust port up with the second sealant that has melted,
the low emissivity film being further included in either the first substrate or the second substrate,
the infrared ray being externally incident through the second substrate to irradiate the second sealant through a region, where the low emissivity film is nonexistent, of the second substrate.
2. The glass panel unit manufacturing method of claim 1 , wherein
the low emissivity film is stacked on the glass pane of the first substrate.
3. The glass panel unit manufacturing method of claim 2 , wherein
the low emissivity film is partially removed from at least a circumferential portion, surrounding an opening formed by the exhaust port, of the glass pane of the first substrate.
4. The glass panel unit manufacturing method of claim 1 , wherein
the low emissivity film is stacked on the glass pane of the second substrate, and
the low emissivity film is partially removed from at least a portion, facing the exhaust port, of the second substrate.
5. The glass panel unit manufacturing method of claim 1 , wherein
the infrared ray is a near infrared ray, and
the second sealant has a near infrared absorbance of 30% or more.
6. A glass panel unit manufacturing method comprising a second bonding step of bonding a third panel, via a third sealant in a frame shape, onto either a glass panel unit manufactured by the glass panel unit manufacturing method of claim 1 or a cut piece of the glass panel unit.
7. A building component manufacturing method comprising an assembling step of fitting a building component frame into either a glass panel unit manufactured by the glass panel unit manufacturing method of claim 1 or a cut piece of the glass panel unit.