Board Thread:General Discussion/@comment-4976518-20140808063123/@comment-8986886-20140913112418

Lucian balthazar99 wrote: what if his zanpakuto spirit knows how evil he is and wont talk to him so he uses the hokyoku to force kyoka suigetsu to do his bidding which is why it's hard to tell what release it is in and why it disintegrated when the hokyoku rejected him

Well, Aizen used Kyoka Suigetsu's complete hypnosis, when he showed it to the captains and lieutenants, before he got his hands on the Hogyoku. The "good" Aizen we saw in the beginning was nothing but a front, he would have been just as "evil" when he first became a Shinigami, and he'd have to be able to communicate with his Zanpakutou to develop a Shikai ability in the first place.