Thanks for your reply... I am using this library already but its not working for me. Even the default adafruit print test is not being printed. I have seen anothe library used in the code https://gist.github.com/1478687
I am asking for that library which is named as <Thermal.h> instead of <Adafruit_Thermal.h> ...
Rest of code is almost the same but the library is different.