Manufacturing Technique

1. Glass Cutting, Cleaning and Film Cutting

  • Slice the glass accurately.
  • Check the glass surface and clean the grease and dirt. Tap water can be used for cleaning.
  • Clean again with soft water. Water quality suggested<30μS,hardness<10 PPM,temperature:40-60℃.
  • Blow-dry the glass to prevent dirt.
  • Film cutting shall reserve 2~5mm over the glass size according to the actual production requirements.

2. Glass Bonding

  • Glass Bonding Room
  • The temperature of the glass bonding room shall be controlled constant between 20~25℃ and the humidity is between 23%±2%. The room shall be no dust inside and the equipment shall be kept clean. The workers all keep the uniforms, caps and gloves clean to prevent dust, particles and hair sticking to the films.
  • Glss Bond Conditions
  • The surface temperature of the glass is suggested to be between 20~30℃ and the maximum is no more than 40℃. The surface temperature of the film is suggested to be between 20~25℃. Check again for the cleanness of the films and glass and if the glass and film match.

3. Preloading and Venting

  • Cold Vacuuming and Heat Vacuuming
  • Vacuuming Venting:Vacuum degree 580~680mmHg, temperature 20~25℃, pressure -0.095~-0.1MPa. The cold vacuuming time for continuous vacuuming is about 20 minutes. If it is discontinuous vacuuming, the cold vacuuming is about 30minutes.
  • Heat Vacuuming: The surface temperature of glass is 100~120℃, the time is 30~45 minutes. The temperature is between -0.095~-0.1MPa. Take out the glass when the temperature is reduced to 60~80℃.
  • Roll-in Venting
  • Preheating of the thermostat→The surface temperature of the bonded glass is 20~30℃ and humidity about 25%→First roll-in, the pressure is 0.2~0.5MPa, the roller spacing is less than the thickness of the bonded glass by about 10%→Thermostat→The surface temperature of bonded glass is 65~80℃→Second roll-in, the pressure is 0.3~0.5MPa, the roller spacing is less than the thickness of the bonded glass by about 15%~20%. Keep continuous operation to keep the temperature of the thermostat constant.

4. High Pressure Forming

  • During the whole process, the heating & pressurization and cooling & decompression should be operated slowly. The following processes are for reference: Heating & pressurization→The temperature is increased to 60℃ and the pressure is 0.4MPa→The pressure is increased to 135~140℃→The pressure is increased to 1.05~1.28MPa→Constant temperature for 30~60 minuted (It is determined by the thickness and quantity of the glass in the pot.)→ Keep constant pressure and reduce the temperature until it is reduced naturally and lowly to 90℃→ Reduce the temperature to 45~55℃ and exhaust.

5. Package And Storage

  • Rolls of PVB films are vacuum-packed with aluminum foil film. There are 2 means of external packing: cardboard tube and wooden case. Generally the PVB films with a width less than 1200mm (including 1200mm) are packed in cardboard tube or cartons, while the ones width a width more than 1200mm are packed in wooden cases. Qualified products are packed with certificated of qualification, packing list, etc.