Technically all reactive resin is based on urethane since they came out around 1993. I believe that a catalyst is what turns urethane into resin. Initially Brunswick labeled all their resin balls, "reactive urethane". This only seemed to confuse the general public, where some thought Brunswick was still making plain urethane. The behavior of resin is so radically different from that of urethane, if we did call them urethane, it would confuse people even more. So the name or label, "resin" or reactive resin", has stuck and is more appropriate, in my view.

Of course, all coverstock materials are some version of plastic, be it polyester, urethane or resin. So would it be better if we just called all coverstocks "plastic"? But then we don't do that either. 

 

 

 

Edited by charlest on 1/26/2011 at 1:19 PM

As far as I know, Yellow Dots, White Dots, Target Zones, and Maxims have always been polyester. All bowling ballcoverstocks are (made of material from the chemical family known as) plastic.