Legal Question in Intellectual Property in California

In general, printing words on cloth is no different than printing them on paper. If the quotation is protected by copyright law, it enjoys the same protection against unauthorized reproduction whether the medium is paper, papyrus, cloth or what-have-you.

Of course, there can be, or are, some distinctions and differences. One might get permission to print paper versions of the quote that would exclude the right to print it on t-shirts, and vice-versa.

Also, the penalty for violation of a copyright might be somewhat different for printing on clothing items than printing on paper, because the copyright holder might suffer and prove different degrees of harm.