Common problems and solutions of glue in LED packaging process

1、 The led turns yellow.

reason:

1. Too high baking temperature or too long baking time;

2. The proportion of glue is not correct. Too much glue A is easy to yellowing.

solve:

1. The AB adhesive is cured and demoulded within 120-140 ℃/30 minutes, and it is easy to turn yellow when baked for a long time above 150 ℃.

2. The AB adhesive is cured and demoulded at 120-130 ℃/30-40 minutes, and will turn yellow when it is over 150 ℃ or baked for a long time.

3. When making large lamp caps, reduce the curing temperature.

2、 LED bubble problem.

reason:

1. Bubble in bowl: the bracket is poorly dipped with glue.

2. Support bubble: curing temperature is too high, and epoxy curing is too intense.

3. Glue cracking and roof bursting: short curing time, incomplete or uneven curing of epoxy resin. AB glue exceeds the usable time.

4. Bubbles on the lamp cap surface: the epoxy adhesive has difficulty in defoaming or the user's vacuum is not enough, and the dispensing time is too long.

Solution: improve the process or contact the epoxy supplier according to the use situation.

3、 Glue climbing of LED bracket.

reason:

1. Capillary phenomenon occurs when the support surface is uneven.

2. AB glue contains volatile materials.

Solution: Please contact the supplier.

4、 The LED package changes color after the short baking is removed from the mold.

reason:

1. The stack in the oven is too dense, and the ventilation is poor.

2. The local temperature of the oven is too high.

3. There are other colored pollutants in the oven.

solve:

Improve ventilation. Remove the color stain and confirm the actual temperature in the oven.

5、 Some of the lamps on the same row of supports are stained or have different gelling time and uneven quality.

Cause: insufficient mixing.

Solution: Stir well, especially at the corners of the container.

6、 It is not easy to demould.

Cause: There is a problem with the AB adhesive or the adhesive does not reach the curing hardness.

Solution: Please contact the supplier to confirm the curing temperature and time.

7、 Add the color agent of the same batch and the same dose, but the color of the product is different.

Cause: uneven concentration of colorant; Or color agent precipitation.

Solution: Heat up the toner and stir it evenly before use.