Fitch claims Panasonic's white goods business could provide it with a stay of execution.
Panasonic has a better chance than rival Sony of surviving Japan's consumer electronics slump because of its unglamorous but stable white goods business, credit rating agency Fitch has predicted.
Fitch cut Panasonic's rating by two notches to BB and Sony three notches to BB minus on Thursday, the first time one of the three major ratings agencies have put the creditworthiness of either company into junk-bond territory.
Rival agencies Moody's and S&P rate both of Japan's consumer electronic giants at the same level, just above junk status. Moody's last cut its rating on Panasonic on Tuesday.
Panasonic "has the advantage of a relatively stable consumer appliance business that is still generating positive margins", Matt Jamieson, Fitch's head of Asia-Pacific, said in a conference call on Friday to explain its ratings downgrades.
But at Sony, he added, "most of their electronic business are loss making, they appear to be overstretched."
Japan's TV industry has been bested by cheaper, more innovative models from Samsung Electronics and other foreign rivals, while tablets and smartphones built by Apple have become the dominant consumer electronics devices.
Investors are focusing on the fate of Sony and Panasonic after another struggling Japanese consumer electronics firm, Sharp, maker of the Aquos TV, secured a $4.6 billion bail-out by banks including Mizuho Financial Group and Mitsubishi UFJ Financial Group.
Sony and Panasonic have chosen divergent survival paths.
Panasonic, maker of the Viera TV, is looking to expand its businesses in appliances, solar panels, lithium batteries and automotive components.
Appliances amount to around only 6 per cent of the company's sales, but they generate margins of more than 6 per cent and make up a big chunk of operating profit.
Sony, creator of the Walkman, is doubling down on consumer gadgets in a bid to regain ground from Samsung and Apple in mobile devices while bolstering digital cameras and gaming.
The latest downgrades will curtail the ability of both Japanese companies to raise money in credit markets to help fund restructurings of their business portfolios.
For now, however, that impact is limited, given the support Panasonic and Sony are receiving from their banks.
In October, Panasonic, which expects to lose $10 billion in the year to March 31, secured $7.6 billion of loan commitments from banks including Sumitomo Mitsui Financial Group and Mitsubishi UFJ, a financing backstop it says will help it avoid having to seek capital in credit markets.
Sony, which has forecast a full-year profit of $1.63 billion helped by the sale of a chemicals business to a Japanese state bank, announced plans to raise $1.9 billion through a convertible bond before the latest rating downgrade.
Thomson Reuters' Starmine structural model, which evaluates market views of credit risk, debt levels and changes in asset values gives Panasonic and Sony an implied rating of BB minus. Sharp's implied rating is three notches lower at B minus.
Standard & Poor's rates Panasonic and Sony at BBB, the second lowest of the investment grade, while Moody's Investors Service has them on Baa3, the lowest of its high-grade category. Moody's has a negative outlook for both firms while S&P sees a stable outlook for Panasonic and a negative one for Sony.