This problem is common, there are three solutions when encounter in this problem.

First look at whether the pattern itself is high-definition, high-quality, if the quality of the pattern itself is not enough, then the printing effect is bound to blur.

The next is to clean the printhead, if the pattern itself is high-definition, then use the software to clean the printhead, it can make effective improvements to the print results.

If the above method is not ok, try reinstalling the print driver (software).