PHILADELPHIA (Sept. 25)—Rohm and Haas Co. expects both improved sales and earnings for the third quarter because of solid demand for its products in many key markets. Earnings per share are projected to be between 40 and 42 cents a share, compared with 33 cents a share for last year´s third quarter. Sales are projected to climb 7 to 8 percent. Revenues for its adhesives and sealants business will drop about 5 percent because the firm exited the liquid polysulfide business, although same-business sales are projected to jump 6 to 8 percent. Rohm and Haas will announce full results Oct. 25.