“Safety Glass” is essential for automobile and construction industries.  Safety glass is safe because it does not shatter on impact. A special thin, transparent plastic film is used as an adhesive between the layers of glass which holds the shattered glass together in the event of breakage. This film is hygroscopic and tends to absorb moisture during storage, prior to manufacturing and during the bonding process.

Effects of Uncontrolled Humidity

The hygroscopic film absorbs moisture and leads to

• Improper bonding of two layers of glass
• Reduces clarity of the glass

Causes of Uncontrolled Humidity

The safety element consists of a special bonding between layers of glass with the internal thin layer film (PVB film). This PVB films is hygroscopic in nature and tends to absorb moisture during storage and assembling process.

The moisture gets trapped between the layers of glass, as bubbles. The trapped moisture reduces the clarity of the glass and the effectiveness of the bond between the two layers of glass, rendering the product unsafe.

General Recommendations

The RH level in the glass laminating area should be maintained at 20-22% with 20°C (68°F).