(FORTUNE Magazine) – Why have Du Pont, Ford Motor, 3M, and Johnson & Johnson raised their quarterly dividends? Some companies increase the payout when a raider lurks, but that's not the case with these big boys. ''We're enjoying strong cash flow and earnings,'' says Du Pont chief financial officer John J. Quindlen. ''It's time to let the shareholders share.'' It's about time, says Eric T. Miller, chief investment officer at Donaldson Lufkin & Jenrette, who points out that while earnings of the S&P 500 index were up an estimated 42% last year, dividends increased only 11%. John Connolly, senior vice president of research at Dean Witter Reynolds, predicts a 10% overall rise in dividends in 1989. Some companies figure dividends are simply the best use of their money, after funding growth. Says Jon Greer, 3M's program manager of investor relations: ''Dividends are higher on the list of priorities as acquisition prices have gone up.'' The 1986 tax act has also spurred some dividend dealing. Says H.J. Heinz assistant treasurer John Mazur: ''We deliberately bumped up the dividend to share the benefit of our lower tax rates and because dividends are no longer being taxed more heavily than capital gains.'' All that talk from Washington about eliminating the double taxation of dividends makes the payouts -- and the companies that issue them -- more attractive. + Companies deny that their generosity is a brazen attempt to bolster stock prices. Says David McCammon, Ford Motor's vice president of finance and treasurer: ''We wouldn't do this if we weren't sure that we could sustain growth. We never want to be in the position that we were in the early 1980s, when we had to cut our dividend.'' Dean Witter's Connolly thinks Ford may be pressured to raise its dividend again this year to keep up with GM, which recently announced a 20% dividend increase: ''The two compete for everything, including kudos from the financial world.''

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