Neutral transparent adhesive yellowing is the defect of the glue itself, mainly caused by the crosslinking agent (curing agent) and viscosing agent in the neutral glue, the reason is that the two raw materials with "amine group", amine group is very easy to cause yellowing, many imported famous brand glass adhesive is therefore yellowing phenomenon. In addition, if the neutral transparent adhesive and acid glass adhesive are used at the same time, it may cause the neutral adhesive to turn yellow after curing; It may also be caused by the long storage time of the glue or the reaction between the glue and the substrate.