Color developing colorless primer

摘要

The intense purple dye normally found in purple primers for use in the adhesive bonding of plastics is replaced with a leuco dye capable developing a visually intense color when activated through contact with the particular plastic being bonded or a complementary solvent cement.

主权项

1. A primer/solvent cement system for use in bonding a plastic object to another object, the system comprising
an essentially colorless primer containing a first organic solvent capable of at least partially softening the surfaces of the plastic object to be bonded, and a solvent cement comprising a second organic solvent and a thermoplastic resin dissolved in the second organic solvent, one of the primer and solvent cement further comprising an essentially colorless color-forming chemical, the other of the primer and the solvent cement further comprising a developer for the color-forming chemical, the color-forming chemical and developer being selected and present in sufficient concentration so that when the solvent cement is applied to a surface previously covered with the primer, the color-forming chemical and the developer combine to develop a visually noticeable color thereby identifying the surfaces of the object to which the primer has been applied.