The majority of inkjet printers used by photographers, designers, businesses, and homes use aqueous (water based) inks that are dye or pigment based. Dye-based inks use a colorant that is fully dissolved in a carrier liquid. With pigment ink, color comes from very fine solid particles that are suspended in the carrier fluid. A good analogy is salt water vs. tomato juice. Once salt is dissolved in water it will not settle out. The solids tomato juice, like pigment colorants, will eventually separate and settle out.
Looking for Decades
How long do you need your prints to resist fade? Is it 10 years, 20 years, 70? Put another way, do you want the prints to resist fade like a professional quality lab print? If your answer to the second question is yes, and if your timeline exceeds 25 years, then you need pigment inks. The science behind pigments allows prints to resist fade for the longest possible time. When you pair pigment inks with high quality inkjet paper and display prints away from bright light, your chances of seeing significant fade before the 50 year mark are low.
Seeking Functionality and Good Looks?
If long-term fade resistance is not critical and your primary need is for bold color and great looks, dye-based inks are a good choice. As a rule, dye inks offer better color gamut and performance compared to pigment inks using the same number of colors. Dye inks will not offer the same fade resistance and in some cases can begin to fade quite rapidly. Because of this possibility, projects such as portfolios, graphic arts presentations, greeting cards, and business materials are ideal. The good news is that Canon and Epson dye inks are vastly improved when compared to ink from 10 years ago. Reports show that even on display, you may see fade resistance stretch into and beyond the 20 year mark with modern dye inks.
With either ink, the type of inkjet paper used affects fade resistance. Your rule of thumb is that non-reflective papers resist fade longer than ones with reflective surfaces. For example, a matte photo paper print will fade slower than a print on a resin coated photo glossy. This maxim is true regardless of paper's brand name or manufacturer.
Red River Paper recommends pigment inks if you want to resist fade more than 25 years. Dye inks are prone to fade in a shorter time frame and in some cases can fade rapidly. Keeping prints out of direct sun, in a frame, and under glazing (glass or acrylic) is the best way to slow fade while on display.