The plastic bottle producer Constar International has increased the size of its proposed initial public stock offering to 16 million shares and cut the price to a range of US$12 to US$15 per share. Originally Constar had been planning to sell 8.8m shares at between US$14 and US$16. The Philadelphia-based company is a unit of packaging giant Crown Cork & Seal Co and Constar said Crown would be selling its entire stake and receiving all the proceeds, which could amount to as much as US$240m.