Solution to Bubble Problem in EVA Film Laminated Glass Production

1. Stop the vacuum pump too early, and stop vacuuming before the temperature drops below 50 ℃. At this time, the EVA film is still in flow, making it easy for air to enter the glass again and form bubbles.

The solution is to stop vacuuming only when the temperature drops below 50 ℃.

2. If the temperature of the silicone bag tray is still very high, let the glass heat up. If the temperature of the bottom plate of the silicone bag is still above 60 ℃, let the glass in. The temperature inside the bag will rise too quickly, and the EVA film at the edge of the glass will melt quickly. If the gas is sealed inside the glass and cannot be extracted, it is easy to produce bubbles.

The solution is to let the temperature of the bag drop below 50 ℃ when putting down a furnace of glass, or to cool and vacuum outside the furnace for about 15 minutes before pushing the vacuum bag into the furnace to raise the temperature.

3. If there is no pre vacuum, the temperature will rise directly. If there is no pre vacuum, the temperature inside the bag will rise too quickly, and the EVA film at the edge of the glass will melt quickly. If the gas is sealed inside the glass and cannot be extracted, it is easy to produce bubbles.

The solution is to pre vacuum for about 15 minutes before pushing the silicone bag into the furnace to start heating up.

In addition, determine the cause of bubble formation from the location where bubbles appear:

Bubbles appear around the four edges:

Stop vacuuming at temperatures above 60 ℃, and air will flow back into the glass with the flow of adhesive;

2. If the processing temperature is too high, the amount of adhesive at the edges will overflow too much, and the amount of adhesive at the edges will become thinner, resulting in bubbles, especially when the middle material is sandwiched;

3. Sealant corrodes the film, and similar bubbles may appear around the glass.

Bubbles appear in the middle of the glass:

1. The furnace heats up quickly, and the film at the edge of the glass melts first, sealing the edges of the glass and preventing air from escaping to form bubbles;

The film used for tempered glass is too thin, and the amount of glue cannot fill the uneven areas to form bubbles;

The gap between the 3 decorative materials is large, and the film is too thin to fill and form bubbles;

When the temperature is too high, the film becomes thinner and bubbles appear, especially when the intermediate material is sandwiched.