How to make ALL prints last longer in sunlight

21 March 2014

One of the key selling points of purchasing a Designjet Z series printer is the fact that the inks are UV stabilised which stops your prints from fading for c. 200 years. So - what happens if you purchased a Designjet T series or CAD printer? How can you extend the life of your prints when you do want to hang them up on the wall for more than a few weeks to stop them from fading?

The answer? - by using swellable papers and where possible protecting the prints under glass or by lamination

The difference between porous and non-porous media

There are basically two types of media - porous and non-porous (as well as a hybrid of the two). The non-porous is also called swellable and it affects print permanence. Most swellable coatings are comprised of either synthetic or natural polymers which swell when they come into contact with ink. The most well known example of a swellable polymer uses a solubilized form of photographic gelatin as the binder. When wet, the gelatin undergoes a chemical reaction where it changes from a hard dry polymer to a rubbery gel state which allows the ink to pass through into it. After drying, the ink is then encapsulated within the coating - which in turn protects it from any contact with air and airborne pollutants.

However one word of warning is that these types of papers can be adversely affected with high humidity levels because with this type of polymer the gelatin can become rubbery or sticky - which could be problematic as the images can become blurry over time. This is the main reason why UV stabilised inks (used by the Designjet Z series printers) are mainly used by the pro market - although dye-based inks are definitely not out of the game and are perfect for the CAD market.  

By comparison, porous coatings are semi rigid coatings made up of millions of microscopic particles and as the ink flows through the particles and across the surface of the particles it gets exposed to air which enhances the drying time. However this means that the ink is very susceptible to air pollutants as they are in continuous contact with air and airborne pollutants and do suffer more from air fade.

Glass and Lamination protection

Another way of extending the life of your prints is to display them with protection - such as under glass or by laminating them. This is particularly important if you have used porous coatings (or quick dry media). This will protect your prints from something that HP call Air Fade. However, be warned that swellable photo papers have a humid and soft surface just after being printed so laminate can peel off easily while a porous photo paper has a dry-to-touch and rigid surface by comparison so the laminate will adhere really well.

Air Fade

Although Air Fade is not completely understood at this time, most research into this subject attributes the ozone as being a significant contributing factor. The likelihood is that in the near future there will be an industry standard showing 'Predictive air fade' displayed against all media - to show customers which products are highly susceptible to air fade versus products that are relatively unsusceptible. 

Research by Henry Wilhelm

Henry Wilhelm presented an article at the International Symposium on Photofinishing Technology entitled "How long will they last" where he compared performance of various photo prints, marking each porous media with this footnote: "Field experience has shown that, as a class of media, microporous papers used with dye-based inks can be very vulnerable to 'gas fading' when displayed unframed and/or stored exposed to the open atmosphere where even very low levels of certain air pollutants are present; to a greater or lesser degree, these papers have a pronounced sensitivity to pollutants such as ozone, and in some locations, displayed unframed prints have suffered from extremely rapid image deterioration".

Examples of HP non-porous (swellable) papers

HP Premium Plus Photo Paper 
HP Everyday Photo Paper 
HP Universal Gloss Photo paper
HP Universal Satin Photo Paper
HP Premium Gloss Photo Paper
HP Premium Satin Photo Paper

Examples of HP porous papers

HP Everyday Instant-Dry Gloss Photo Paper
HP Everyday Instant-Dry Satin Photo Paper
HP Universal Instant-Dry Gloss Photo Paper
HP Universal Instant-Dry Satin Photo Paper
HP Premium Instant-Dry Gloss Photo Paper
HP Premium Instant-Dry Satin Photo Paper
HP Professional Instant-Dry Satin Photo Paper
HP Premium High-Gloss film 
HP Photo Paper 
HP Photo Quality Paper, two sided