Why all 4 corners of the laminated glass the white is lighter than the centre of the laminated glass
Put something surround the laminated glass with same thickness(or slightly higher), for example wood bar, which is to make the pressure of corners of eva glass laminate same as the center of eva glass laminate.
We laminated a sample of 2 pieces 5mm 300mm x 300m with 2 pieces 0.38mm Cool Jade white eva film interlayer . Our process cycle was as follows:
30min de-airing at maximum vacuum (-0.1MPa)
20min at 75 degrees Celsius
40min at 135 degrees Celsius
120min cool down cycle to room temperature of 25 degrees Celsius
We have noticed on the all 4 corners of the laminate the white is lighter than the centre of the laminated sample. Please see image attached.
We are using silicon vacuum bags for lamination in our vacuum oven.
We suspect the reason this occurred is because the vacuum is very high and creates slight more vacuum pressure on the corners. Please can you advise what we should do to eliminate this problem. We are able to reduce the vacuum and temperature cycle if needed. (see picture of our vacuum gauge)