Abstract: An improved thermal ink jet recording paper, incorporating heat aged precipitated calcium carbonate ("PCC") and a binder, is disclosed. Heat aging the PCC in the presence of an organophosphonate produces discrete particles of PCC with a surface morphology and chemistry that enhances the ability of the PCC to bind to ink jet ink without binding so strongly that the color of the ink is changed. Ink jet recording papers incorporating the PCC and binders of the present invention have reduced feathering, spreading, and penetration or backside showthrough, as well as improved optical density, dry time, and water fastness.