The main function of the first sealing rubber of insulating glass in the automatic production line of insulating glass is to realize the positioning assembly of the spacer frame-glass, which provides the basis for the application, curing and molding of the second sealing glue. It can not bear the structural bond fastness and lateral load transfer, but it is effective to resist the penetration of water vapor, especially in the products filled with inert gas can effectively block the loss of gas permeation.

At present, the first sealant mainly uses hot-melt butyl sealant. Butyl tape can be used as a substitute.