Longer life for digital prints

Most of us feel comfortable using the office printer to create documents containing full-color photos—if we plan to use those materials right away. But what about photos that need to be stored with a paper file and might need to be accessible for months or even years? What about photos that will be displayed in the lobby or around the office? How long will digital prints last before they start to fade, run, or turn yellow?

The answer depends on a number of different factors, including the type of printing technology used, the type of paper used, and where and how the prints are stored.

Printing technology factors

Today, three main types of printing technology are used to turn digital photographs into prints: inkjet, dye sublimation, and digital silver halide (lab processing). Of the three, inkjet printers are the most common.

Inkjet printers can be subdivided into those that use pigment-based inks and those that use dye-based inks. Pigment inks sit on the paper’s surface, while dye-based inks are absorbed by the paper. For either type of ink, choosing the right paper has a dramatic impact on both quality and longevity.

Inkjet photo papers come in two broad categories: "instant-dry" or porous papers, and "encapsulating" papers. The instant-dry photo papers use a thick, inorganic coating to spread the ink over a large surface area; unfortunately, this also makes the papers susceptible to fading within months. By contrast, encapsulating papers such as HP Premium Plus Photo Paper use organic polymers that swell as they absorb the dye, thus encapsulating it and protecting it from air fade.

Environmental factors

When testing digital prints for longevity, scientists typically consider four factors: light fade, thermal degradation, air fade, and humidity. Independent research on these four factors conducted by Wilhelm Imaging Research, Inc., found that the longevity of digital photo prints varied greatly depending on the type of printing technology, the quality of the materials used, and the storage environment:

• Digital Silver Halide: In storage, lasts 100 or more years; exposed to air, lasts decades; displayed under glass, lasts 17 to 40 years.

• Inkjet: In storage, lasts 100 or more years; exposed to air, lasts months (for most dyes on porous paper) or decades (pigments or dyes on encapsulating paper); displayed under glass, lasts anywhere from 5 to 100 years or even longer, depending on quality of paper and ink.

• Dye Sublimation: In storage, length currently unknown; exposed to air, lasts decades; displayed under glass, lasts 4 to 8 years.

Surprised? Inkjet prints actually lasted as long or longer than lab-processed prints in most situations. The key to obtaining the best results was using inks, papers, and printing technologies that were designed to be used together.

So how can you make your digital prints last as long as possible? If you're using an inkjet printer, make sure you use a high-quality encapsulating paper, like HP Premium Plus Photo Paper, as well as ink designed for use with that paper. If you're displaying photos, protect them with glass to prevent air fade. Finally, as much as possible, store photos away from direct light, heat, and humidity.

© 2005 Hewlett-Packard Development Company, L.P.