Private equity firm Bain Capital agreed to invest $350m in II-VI, a provider of engineered materials and optoelectronic components. Bain Capital will use the additional $350m to purchase a total of 140k shares of II-VI Series B-2 Convertible Preferred Stock. All of the shares of Series B Convertible Preferred Stock will be convertible into shares of II-VI common stock at a conversion price of $85 per share.