HUATESHENG PVB

Cutting glass precisely and cutting tolerance must less then 2mm to avoid bubbles. Polish the glass edges and wash glass with softened water, then dry the glass and put into the laminating room.

The laminating room should be clear and dust-free, and operator should wear neatly. Room temperature should be 15-25°C and the humidity 18-40%. Full prelaminating process as following:

a. Lay one piece of clean glass on table.

b. Place the PVB film on the glass, the edge of cutting PVB film should 2- 5mm more than the edges of glass. Do not touch the glass when cutting PVB film.

c. Lay another piece of clean glass on PVB film.

In order to get well sealed edge, the air between the film and the glass needs to be pressed out. As normal, there are two methods below:

a. Rolling De-airing

The pre-laminated glass to heat up to 25-40°C on glass surface and put it into the first roll by the space of roll is 1mm less than the thickness of laminated glass with pressure in 0.2-0.5 MPa. And also enter into thermostatic container to heat up to 60-80°C. Then through the second roll by the space of roll is 2mm less than the thickness of laminated glass with pressure in 0.3-0.5 MPa. After finishing to second roll, seal the four sides of laminated glass with clear tape to avoid bubbles.

b. Vacuum De-airing

Put the pre-laminated glass into a vacuum bag or vacuum rubber gasket, then use the cool or heat pumping to expel the air. Recommend: the decompression vacuum degree is exceed 650 mmHg. For the cool pumping temperature should be lower than 25°C and keep it for 30-40 mins; while in the period of heat pumping, the temperature should be 70-120°C and keep it for 30-60 mins.

Put laminated glasses into autoclave and note the space of two pieces of laminated glass is exceed 5mm. Then sealing the autoclave door to raise the autoclave temperature up to 80°C and then raising rate in 5°C per minute after temperature 80°C , and also the pressure in 0.06MPa per minute. When it up to 120-140°C and 1.0-1.5MPa, keep the temperature and pressure for 30-60 minutes. After that, keep the pressure and lower the temperature to 80°C，at the same time，loose the pressure to the atmosphere pressure. Finishing the high pressure molding process, we can have the final laminated glass for usage.