Softbank Corp., the fastest growing mobile phone operator by subscribers, unveiled 15 new handsets Monday in an effort to close the gap with bigger rival KDDI Corp., which introduced 10 models.

Among the phones Softbank released was a minicomputer model that automatically checks e-mail from Yahoo Japan Corp.'s server, similar to the service offered by Apple Inc.'s iPhone. The new phones will go on sale early next month, Softbank said on its Web site.

Six of KDDI's new models have new movie and television services.

Softbank is winning new users in a market jointly controlled by market leader NTT DoCoMo Inc. and KDDI to the tune of 82 percent.