To shorten adjusting time while dispersion is removed by a method wherein printing is carried out by changing fading adjusting time automatically in stages.

When print quality adjusting switch is pushed down, hammer delay time is automatically made plus and minus, printing is started shifting a specific time in an order from a small delay time to a large delay time, and a control to be ended is carried out. Since printing is carried out changing stepwise shift amounts lf1, lf2, lf31,...lfn, a position at which fading fits best is easy to be detected. Then, an adjuster, after end of printing, sets the position at which the fading fits best by seeing the printing sample. Thereby, dispersion between machines of printing quality owing to dispersion in setting a manual by the adjuster can be lessened, and printing time can be extremely shortened.