need help on wide format printers

[Lionheart]

I'm looking to purchase a wide format printer capable of printing on canvas that is archival. All I see out there are Epson printers. Our 18x20 b&w portraits in the reception area are turning green under the lights even though these are supposed to be archival inks (they were printed on canvas from wideformat Epson at a local printer). Does HP make a large format printer? I've printed a ton of inkjets from my HP's and they have yet to fade under the flourescent lights in my operatories at work. Any suggestions would be greatly appreciated. PM me with any recommendations as well please. Thank you all in advance