styles from "screen" css appear in print

I have different style sheets for screen and print media (there is a css with text sizes for all media).

display: none; in the print style sheet works perfectly.
However, when I print a lot of the styles from the screen css appear, even if I specify something different in the print css. For example I've set all text to black in the print style sheet, but it continues to be in colours when printed. What is the reason?

Would be great if someone could have a look and shed some light.
http://new.fightforsight.sigma.titaninternet.co.uk/make-a-donation
Print style sheet: 10_print.css
Screen stylesheet: 03_default.css
All: 01_text_sizes.css

I thought only the "print" and "all" styles would appear in print but not the "screen" styles. Many thanks.

I'm out of ink I so can't see a paper copy of your linked page. However, in the print preview modes of both Opera 9.5 and IE7 all the text of your site appears black - this would seem to suggest that your print.css is working fine.

looks all black to me...