A securities filing unveils new insight into how popular Raleigh chemistry startup Undercover Colors really is with backers. The company, which is developing a nail polish execs say can detect the presence of date rape drugs in a drink, raised $5.5 million in recent equity financing. And, according to a Nov. 10 filing, a whopping 49 investors participated in the funder. David Gardner, a Cary angel investor, was the first to financially back the firm two years ago, and he said Thursday he wasn't...