Method of manufacturing translucent rigid substrate laminate and translucent rigid substrate bonding apparatus

A method of manufacturing a translucent rigid substrate laminate, comprising:

• 1) a process of preparing a first translucent rigid substrate;
• 2) a process of preparing a second translucent rigid substrate;
• 3) a process of applying a photo-curable fixing agent including (A) polyfunctional (meth)acrylate, (B) monofunctional (meth)acrylate and (C) a photopolymerization initiator to a first surface of the first translucent rigid substrate and/or a first surface of the second translucent rigid substrate;
• 4) a process of allowing the first surface of the first translucent rigid substrate and the first surface of the second translucent rigid substrate to face each other so that the both surfaces are parallel to each other in a predetermined positional relationship in a surface direction;
• 5) a process of applying a given pressure to the first surface of the first translucent rigid substrate and the first surface of the second translucent rigid substrate while maintaining the positional relationship to bond the both translucent rigid substrates;
• 6) a process of irradiating light for curing only an outer peripheral portion of the fixing agent spreading between the both translucent rigid substrates to form a provisionally fastened translucent rigid substrate laminate;
• 7′) a process of repeating the processes 1) to 6) at least once by regarding the provisionally fastened translucent rigid substrate laminate as the first translucent rigid substrate to form a provisionally fastened translucent rigid substrate laminate in which at least three translucent rigid substrates are bonded;
• and
• 8′) a full fastening process of curing the uncured fixing agent present in the provisionally fastened translucent rigid substrate laminate obtained in the process 7′) to form a fully fastened translucent rigid substrate laminate.

A translucent rigid substrate bonding apparatus, comprising:

• an upper stage having a suction hole for vacuum suction of an upper translucent rigid substrate to hold the upper translucent rigid substrate;
• a press unit for moving the upper stage in a Z-axis direction;
• a suction unit for applying a suction force to the suction hole;
• a lower stage for holding a lower translucent rigid substrate;
• a means for moving the lower stage in an X-axis direction, a Y-axis direction and a θ-axis direction;
• a means for applying a photo-curable fixing agent including (A) polyfunctional (meth)acrylate, (B) monofunctional (meth)acrylate and (C) a photopolymerization initiator to either one or both of a lower surface of the upper translucent rigid substrate and an upper surface of the lower translucent rigid substrate;
• and
• light irradiators arranged at such positions as to irradiate light toward outer peripheral portions of bonding surfaces of the both translucent rigid substrates.