There are several companies who produce solid surface material.
Below, the main companies are listed along with characteristics unique to their product.

Corian
Probably the most well known of all solid surface, Corian was the front runner of the
solid surface industry. There are over 110 Corian colors and the number continues to grow. 

Hi-Macs
A more affordable solid surface along with a rare fifteen-year
warranty makes Hi-Macs an attractive option.

Avonite
For truly unique colors and intriguing design options, Avonite is an excellent choice.
They offer three translucent colors that allow counters to be back-lit.

Staron
Although they focus on classic colors, Staron has added variety with numerous
large-particulate selections, a very popular alternative to granite.