NEW YORK (Standard&Poor's) Dec. 1, 2010--Standard&Poor's Ratings Services said today that it assigned its 'BBB' senior unsecured debt rating to Eastman Chemical Co.'s proposed offering of $500 million of senior unsecured notes with five- and 10-year maturities. All our other ratings on Eastman, including the 'BBB' corporate credit and 'A-2' commercial paper ratings, remain unchanged. The outlook is stable. Eastman expects to use proceeds from the proposed offering primarily to pay for notes purchased in its recent tender offer for up to $500 million of its outstanding senior unsecured debt securities. We expect the transaction to spread out debt maturities and lower borrowing costs. The ratings on Kingsport, Tenn.-based Eastman reflect its satisfactory business profile as