The raw glass is scrubbed clean to remove any impurities, after which the first sheet of quality float glass is fed along the laminating line. A PVB interlayer is drawn over the first sheet of glass and a second sheet of glass is then placed on top of the PVB to create a 'sandwich'. This 'sandwich' passes through a specialised press and heating process which removes most of the air and effectively fuses the three items. The laminated sheets are then stacked in a specific configuration for loading into an autoclave. Finished laminated sheets are stacked in a dedicated laminates warehouse. A silver metallic coating can be applied to a surface of high quality float glass, by the magnetron sputter process in order to enhance the solar heat eliminating properties of laminated glass.
The glass of desired thickness is loaded into the laminated glass production line, initially it is cleaned using deionized water. After this, the glass is transferred to a clean room where the PVB is stored, this facility also has an air conditioning system to ensure that the PVB film is stored properly. A clean environment is mandatory for the storage facility as any dust particles sticking on to the film can cause de-lamination.
In the clean room, the cleaned glass is placed over the aligning table, over which the film is carefully placed with proper geometrical alignment, after which, with the same precision, the second layer of glass is placed on top. Next, the sandwich is released in the roller which takes it for pressing (to remove air bubbles) and controlled heating (to soften the PVB). Finally, the unit is taken to an autoclave where it attains the form of actual laminated glass. In the autoclave, the unit is heated (100 to 150degree) under controlled pressure (8 to 10bar).