Regarding the impact of moisture on UV glue, there are two types of discussions: uncured glue and cured glue:

When UV glue is not cured, humidity has no effect on UV glue (except for moisture curable UV glue) under most normal conditions (0-70% relative humidity). It will not affect the curing time, chemical properties, and adhesion to the substrate. However, at 70% RH or higher, we need to pay attention to the surface of the substrate. Due to high humidity, air can condense or adsorb on the surface of the bonded material, which actually acts as an obstacle between the UV adhesive and the substrate, thereby reducing the adhesive strength of the UV adhesive to the material.

For uncured UV adhesive, pre bake the material and perform bonding and curing treatment in an environment that can control humidity;

2. For cured UV adhesive, prolonged exposure to high temperature and humidity may cause hydrolysis of the adhesive layer structure, which may affect some acrylic modified polyurethanes, thereby reducing adhesion and the cohesion of the UV cured material.

For cured UV adhesive, applications exposed to these conditions should undergo comprehensive testing before deciding whether to use it. This effect can be seen from the water absorption rate in the product documentation, but it is not the only reference and testing must be done in practical applications. Reducing the exposure limit of UV adhesive wires through appropriate design can reduce the impact of humidity on the adhesive.