Ink jet recording apparatus

An ink jet recording apparatus to perform printing on a recording medium in which two or more unexposed regions subjected to processing such as trimming, pasting and folding after the printing and thereby unexposed exist in a mixed manner, comprising:

• an ink jet head in which a plurality of ink discharge nozzles are arranged to cross with respect to a conveyance direction of the recording medium;
• a spit position determining unit which determines a spit position based on size information and unexposed region information of the recording medium;
• and
• a spit control unit which controls spit of the ink jet head based on a spit position judgment result of the spit position judgment unit,
• wherein said unexposed region information defines regions on the recording medium surface which are unexposed or cut away after printing and processing, and said spit position determining unit selects two or more unexposed regions and determines the spit position so that all the ink discharge nozzles perform the spit.