Investors remain confident in certain thin-film technologies. Konarka Technologies isn’t one of them.

The Massachusetts-based organic solar thin-film filed for Chapter 7 bankruptcy protection and will cease operations. Howard Berke, Konarka’s chairman, president and CEO, said the company was unable to obtain additional financing and is unable to continue operations. Despite the grim circumstances, Berke is still holding out hope for the company. Several large international companies had expressed interest in financing or acquiring the company, Berke said in a statement.

Konarka hasn’t always struggled to attract the funds it needed. The company was founded in 2001 by Berke and Alan Heeger, the won the Nobel Prize for his work in conductive polymers. Heeger invented a photo-reactive polymer material that can be printed or coated inexpensively onto flexible substrates using roll-to-roll manufacturing. The company’s Power Plastic, which converts light into electricity, can be manufactured into a number of end-use products including curtain walls (see photo) and portable shade structures and even sunbags designed to charge mobile phones and Mp3 players.

By my count, Konarka raised more than $150 million in venture capital, seed funding and private equity money, including a $45 million investment from Total. That’s not including a $1.5 million loan from Massachusetts’ clean energy fund while presidential candidate Mitt Romney was governor; another $5 million loan in 2009 for manufacturing and job creation from two state government funds (this time under Gov. Deval Patrick’s watch); and a $6 million grant from DARPA. Other investors include 3i, Chevron, Draper Fisher Jurvetson, Mackenzie Financial and New Enterprise Associates.

Konarka was targeting a couple of markets, notably the nascent building-integrated photovoltaic market (BIPV). Breaking into the construction business is hard enough. but Konarka had the added challenge of selling a product that was only able to convert a small percentage of the sunlight into electricity.