Is there copy paper with the word copyright used as a watermark?
I am not aware of any paper of this nature, however I may suggest that you set type saying “© Your Name” and turn it into a15-20% screen. You can then place this on your page, behind the type or whatever you are publishing. Graphic Designers often use this as a method of protecting artwork when giving proofs to clients. A screen of the word PROOF is placed right over the artwork. This simple screen will then show up on the page if anyone tries to copy it, and will be denied to be printed by any reputable copy or print establishment. Hope this helps you. Best wishes.