Intel Corp., the world's largest chipmaker, sold $5 billion of debt in its first non-convertible bond offering in more than two decades as issuance revives in September with borrowing costs at about record lows.

Proceeds will mainly be used to fund stock buybacks, Santa Clara, California-based Intel said today in a statement distributed by Business Wire. The chipmaker last tapped the market for bonds that aren't convertible into stock in 1987, according to data compiled by Bloomberg.

PNC Financial Services Group Inc., which is buying Royal Bank of Canada's U.S. retail banking unit, American Express Co. and mining firm Rio Tinto Plc were among companies that sold $12.2 billion of debt today as yields on investment-grade corporate debt hover within 30 basis points, or 0.3 percentage point, of the lowest on record, Bank of America Merrill Lynch index data show. A combination of the weak stock market and low rates are likely driving Intel's bond sale, said Rajeev Sharma of First Investors Management Co.