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Pre-Catalyzed Lacquers vs. Polyurethane coating for furniture

Pre-Catalyzed Lacquers vs. Polyurethane coatings for furniture


Pre-catalyzed lacquers have been a great invention, they look great and are harder and tougher than regular lacquers, but they have some draw backs and aren’t always the solution to your finishing needs.


A pre-catalyzed lacquer is a formulation that has an additional catalyst added to it at the factory that makes it harden when it cures. You can smell the difference in-between regular lacquer and a Pre-Cat as the Pre-Cat has a distinctly more acrid smell. That’s the acid additive that when applied reacts with the air and the other solvents in the mix to make a chemical cure as appose to just an air dry cure. The benefit is a tougher and more water resistant finish.


It has the look and feel of a Lacquer but will yellow over time. Some more than others the better the material the less it will yellow. With the exception of one lacquer I know they all do this. Another problem I have had with all pre-cats is that as they are exceptionally harder (that’s  a good thing for abrasion ) they also have the higher tendency to crack on the joints of the cabinet doors and where raided panels have there connection to frame of the door.


The draw back is that it’s not and impervious coating which I guess, you could say about any coating but that being said I have had customers tell me that they have had call backs with panels in font of sinks that needed finish repair after a year.


What’s the solution? I have found there to be two good solutions  Conversion varnishes of which I have found a water based version that at this time appears to be doing as good as the solvent based version and then there are the polyurethanes which have become my choice of materials. They are more expensive, and harder to handle being a two part material (it comes in two cans and you have to mix one with the other in the right amounts) and it has a pot life, that means that it is going to harden up on you if you let it sit in your spray gun more than about 4 hours.  


 Those are the down side to the material.  On the up side you have a finish that doesn’t yellow with age and it hard enough to be use for exterior applications. For example front doors exterior wood trim and wooden patio furniture and as a poly it is made with a certain amount of elasticity, the ability to stretch. Wood will expand and contract with temperature and moisture so you want a coating that will do the same. 


I have one customer that used the material very successfully on high end pool furniture   for a classy roof top bar in down town LA.


Classically where finishers have finish failures is on the doors in form to of the sinks water splashes out and then isn’t cleaned up after wards. It tends to puddle on the trim and after a while will work its way under the finish and then peels.


Two of my highest end finishers are looking at switching to the polyurethane exclusively and while that is something that they can do being as large as they are. What the smaller shops can do that  doesn’t generate the higher costs and yet prevents the call backs is to do the high water areas in the polyurethane and the rest of the kitchen in the Pre-catalyzed materials. 


 I  am a sales and service  rep for several different manufactures and would be happy to recommend materials to any one that asks, The Great thing about my job is that I push the products that work the best rather than being constrained to on brand of material I have several and I’m always  looking for new and better.




Greg Saunders


7450 Reseda Blvd.

Reseda California 91335


October 25, 2008 Posted by | Conversion varnish, polyurethane, Wood finishing | , , | 16 Comments