What is the difference between a catalyzed and a non-catalyzed finish?— Mike DiMaggio

Richard Oedel replies: It’s all about the chemistry. A catalyzed finish is a coating where the molecules cross-link in the presence of a catalyst, so the coating is generally more durable and less affected by solvents. There are two general types, pre-catalyzed and post-catalyzed. The pre-catalyzed comes directly from the manufacturer with the catalyzer already added. The benefit—no fussy mixing. The drawback—it does not cross link as fast, so it takes time to build the hardness and durability in the finish and the product goes bad in the can after about 6 months even if you never open it! 

A non-catalyzed finish is anything else.