Expensive petroleum-based chemicals are going out of style, as renewable sources are growing in demand. In the case of furniture varnishes, researchers at the Institute for Wood Research in Germany have developed an alternative product in which nearly all petrochemical components have been substituted.  The new water-soluble furniture varnish is comprised of vegetable oils and sugars and has identical properties to conventional varnishes.  It is hard-wearing, scratch-proof and resistant to chemical attack.

 

"This varnish offers the coatings industry an attractive alternative to petrochemical products that is economical to produce and performs well in all tests," reports Dr. Claudia Philipp of the international company Fraunhofer WKI (www.fraunhofer.de).  The new varnish is based on the chemical compound 1,3-propandiol, which is derived from glycerin but has been relatively ignored until now.  Glycerin is the basic substance found in all vegetable oils, and is a readily available byproduct of manufacturing processes for fatty acids and biodiesel.  

 

 

The researchers transformed 1,3-propandiol into polyurethane, which serves as a binder in hard, transparent, scratch-resistant varnishes. "The aim is to use the relatively cheap 1,3-propandiol as a substitute for one of the more expensive petrochemical synthesis components, without altering the coating properties of the varnish," explains Dr. Guido Hora, department head at the Fraunhofer WKI.

 

The polyurethane doesn't chip when a cup or other object is dropped onto a table, which is important in preventing damage to the furniture under the coating.  Another advantage of the new varnish is that it does not contain NMP, a solvent once widely used in polyurethane coatings and known to have toxic effects.

By Neil Whitehall
Get Furniture Jobs, Contributing Editor