Sony Corp. and Panasonic Corp. will dissolve their partnership developing organic electroluminescent television displays as they have not been able to establish a cost-effective means of mass production, sources close to the two companies said Wednesday.

The electronics makers, which have jointly developed the displays for 1½ years, will end the tie-up as the contract expires at the end of this year.

But the two companies will continue development of OEL TV technology independently.

Improving the profitability of their respective TV divisions has been an urgent challenge for both Sony and Panasonic. For the time being, the companies will focus their financial and personnel resources for the development of "4K" liquid crystal display TVs, which show images at four times the resolution of high definition, the sources said.

Under the partnership, Sony and Panasonic were planning to catch up with South Korean rivals LG Electronics Inc. and Samsung Electronics Co., but they could not maintain the quality of the panel or lower production costs.

The South Korean pioneers have also been struggling with the OEL display business due to high costs.