I've read something somewhere that said the photo cartridges lose about half their brilliance in the first wash.
The big "breakthrough" was supposed to be the new pigment based inks. Supposedly more permanent than the old dye based. So I switched to a new printer. I haven't gotten a decent result since. I was beginning to think I must be doing something wrong, although I could swear I'm doing everything exactly the way I used to with the old printer. Until I stumbled across this article on the internet ...
http://softexpressions.com/help/faq/FAQbjs.htm#c82
Pigment based inks are more water resistant, but NOT more durable when actually washed. So, I'm going surfing TODAY to see if I there are any printers left on the market that still use the dye based ink.
I'm so glad I found that article. I was on the verge of "upgrading" to a wide format printer that used the pigment inks. I'd have wasted several hundred dollars!