Previous blogs discussed catalyzed varnish, lacquer and catalyzed lacquer. In the final blog in this series, we’ll see how knowledge of each of these leads to a better understanding of pre-catalyzed lacquer.

Pre-catalyzed lacquers are made from the four primary types of raw materials. See “A Closer Look at Catalyzed Varnish” for more information. They are a blend of lacquer (cures by solvent evaporation) and catalyzed varnish (cures by cross-linking), just like post-catalyzed lacquer. See “Catalyzed Lacquer – Durability Meets Aesthetic”, “Exploring Lacquer” and “A Closer Look at Catalyzed Varnish” for more information. Lacquers were popular for their ease of application, and then when more durability was needed, catalyzed varnishes were used. A hybrid of the two, post-catalyzed lacquer, was developed to have easier application than catalyzed varnish and more durability than lacquer. Then pre-catalyzed lacquers filled the void for a very easy to apply coating that did not require the finisher to add catalyst, but still meet many industry standards for durability.

Pre-catalyzed lacquer is the easiest to use interior wood finish that is able to meet various industry requirements for cabinetry and furniture. Pre-catalyzed lacquers don’t require the finisher to add the catalyst; it is already added at the manufacturer’s factory. This eliminates the errors that can occur in measuring and adding catalysts in the field. It also allows the coating to be checked for quality with the catalyst to verify that the curing will be correct.

Why would anyone use post-catalyzed coatings? Post-catalyzed coatings typically cure faster and to a higher density of cross-linking (more chemical resistance and hardness). This makes post-catalyzed worth the extra effort in short and efficient line conditions where a more durable coating is required. So if you need a very durable coating that cures quickly, post-catalyzed coatings are the choice.

Pre-catalyzed lacquers obtain their long shelf life of several months to a year or more by using resins that are more stable in the presence of the catalyst, a weaker catalyst, and the solvent system. While this allows for a long shelf life, it means the coating cures slower. This usually results in more time required for the coating to cure to a less cross-linked film (less chemical resistance and hardness).

While the finisher doesn’t need to catalyze the coating, there are factors the finisher does control that will affect the shelf-life (or pot-life) and the cure of the coating. Storing pre-catalyzed coatings at higher temperatures will shorten the shelf-life. Typically shelf-life is evaluated at 77F in a sealed container; temperatures above that may cause the product to fail before the shelf-life is reached. Also, the temperature of the coating, substrate and air during application and curing will affect the cure. Remember, high temperature acts like extra catalyst and low temperatures acts like less catalyst. So, finishing wood at lower temperatures will slow the cure and the final cure may be less than expected. Likewise, higher temperatures will speed the cure and increase the final cure. Ask your supplier what the correct temperature range is for the coatings you use.

Pre-catalyzed lacquers have found a niche in being the easiest to apply interior wood coatings that pass many industry durability requirements. This will keep them as a viable option for years to come.

Comment on this story pre-cats Created by Greg Saunders in 5/9/2012 11:45:41 PM thanks for the article however something that I would add is that you have to use a vinyl sealer or a "non sterated" sealer with catalyzed products as the acids that are used as catalysts can react with the sterates in a regular sealer, sterates being the additives in a sealer that make it sand easily. Your Name Email Website Title Comment New Comment Enter the code