Berlin-born Karl Zerbe, who dislikes oils, has painted with egg yolk, casein, fig milk, wax soap, Duco auto enamel and hot beeswax. His wax techniquea revival of the ancient encaustic method in which colors are mixed with hot wax and afterwards cooked into the canvasbrought him critical acclaim. But in 1949, things began to go wrong. Zerbe started suffering from asthma, found that he was allergic to beeswax.
Painter Zerbe set out to find a new medium. The answer was polymer tempera, a plastic mixture developed by one of Zerbe's former students at the Boston Museum's art school. Polymer tempera is made...