Latent curing agents are used in a wide variety of coating, adhesive and sealant applications. These curing agents are particularly beneficial where high build properties are required, for say waterproof coatings and construction sealants. This range of curing agents can be used in both one and two component PU systems. They are normally used with aliphatic prepolymers in one component systems. They promote fast through-cure with no carbon dioxide gas evolution. The curing agents hydrolyse on exposure to moisture, yielding reactive amine and hydroxyl functional groups.
While in two component systems they can be also be used with aromatic prepolymers or isocyanates.
The range of latent curing agent consists of Incozol 4, which is a standard bis-oxazolidine curing agent, Incozol HP is a high purity curing agent plus Incozol NC & Incozol K which are non-crystallising curing agents.
Curing Mechanism
The curing mechanism, which differs from the traditional "moisture cure" reaction, chiefly determined the unique properties of the latent curing agents.
Moisture reacts directly with the terminal isocyanate of the prepolymer generating gaseous carbon dioxide inn this process. This results in blisters, bubbles or foaming in the coating film.
