Charlotte-based EnPro Industries Inc. has agreed to buy a small California company specializing in optical filters and plasma coatings in a deal valued at $255 million. The deal to buy Alluxa Inc. is expected to close in the fourth quarter. EnPro (NYSE: NPO) CEO Marvin Riley says the acquisition complements his company's growing advanced-technology portfolio. "The business adds to our robust expertise and expands the suite of proprietary products and services we offer to our customers," he...