neghcho said:
There are white opaque inks out there, i know i've seen them, but it's probably not worth the effort trying to track them down.
I've never seen such a thing except for DTG printers. All printers work the same way that photographs do. They begin with a white surface and then add verying amounts of colors to dreate a image. The lightness of a color is due to the fact that the ink is thin enough for the white surface to show through. A printer makes colors by putting ink down on the page. To make white, it simply does nothing. In other words, if you were to print a red page, you'd put down a lot of red ink. To print a white page, you'd simply eject a blank page with no ink on it at all. With all that in mind, I'm not sure what a printer would do with white ink. It thinks white comes from the paper.
DTG printers are the only exception that I know of. They have specially writter print drivers and the fermware of the printer is replaced with a re written version to teach it how to use white ink. No printer in the normal comsumer market can be made to do that that I know of.
Only option that I can think of is to give it white ink in the black slot and tell it to print black. Basically, that's exactly how the laser white toner will work when it comes out in a couple of weeks from now. However, that process will require two separate laser printers. One for the color, and the second for the white toner.