To easily allow escape processing to be performed according to an output destination without omission.

A neutral character conversion information storage means 1a stores neutral character conversion information which corresponds a special character to a predetermined neutral character not used by each service providing means. A safe character conversion information storage means 1b stores safe character conversion information which corresponds a neutral character to a predetermined safe character string having one or more safe characters used for character reference by a second-stage service providing means 1f. A first conversion means 1c converts the special character included in data into a neutral character on the basis of the neutral character conversion information stored by the neutral character conversion information storage means 1a and outputs it to a first-stage service providing means 1d. When acquiring processed data from the first-stage service providing means 1d, the second conversion means 1e converts at least a part of the neutral characters included in the processed data into a safe character string on the basis of the safe character conversion information stored by the safe character conversion information storage means 1b, and outputs it to a second-stage service providing means 1f.