Information about the life of inkjet prints
How long will inkjet prints really last? Sales brochures promise well over 100 years - however we will not live long enough to see and check. And then there is the other reality when sometimes prints, displayed on the wall, change colour after a few months already.
Opposite to traditional (chemical), analogue black and white enlargements which have existed for more than100 years already, and of which many still are very presentable (even those from the 19th century!); with inkjet printing we have much less experience yet. Most inkjet prints from the early days look today - after 20 years - quite pale and discoloured, and the edges of the first nano- or microporous coated photo papers turned yellow meanwhile. However, the development since has made tremendous progress: today's ink and media have little in common with those from the 90’s.
What are the facts?
To help judging, accelerated aging tests shall simulate within a few weeks of what could happen to the print within many years. And the results sound promising: more than 100 years, even 200 years print life are stated by many research institutes! But these aging tests are neither standardized nor do they truly reflect the real conditions which act on the prints over years and years, and sometimes act together, amplifying each other.
In the following, we like to give you some basic information so you can get a better idea how long your inkjet prints will last. Because all of this is dependent on several factors...
1. The ink
The ink is the predominant factor. The light stability of pigmented inks is higher than that of dye-based inks. In fact, the pigment inks from the leading manufacturers (e.g. Canon Lucia, Epson UltraChrome, or HP Vivera) are very durable; their stability is very similar and should warrant a print life of 100 years and more under good indoor conditions, before visible colour fading will occur. Also, pigments offer a high stability against water and humidity.
On the other hand, dye inks have a reduced stability with porous surfaces. Polymer-coated papers would provide much better protection as the polymers cover and screen the dyes; unfortunately there are hardly any polymer-coated papers left on the market. Almost all RC photo papers, glossy cast-coated papers, and all matt-coated papers have porous coatings today. Some dye inks fade quickly when exposed to ozone and other oxidizing air pollutants, however many dyed inks have improved a lot in the last couple of years, and at least under controlled, clean conditions, also the dye-based inks of the leading printer brands have a reasonable longevity today.
The dyes used in inkjet dry minilabs are an exception since these are polymer encapsulated and therefore protected from most environmental effects. Their durability is similar to that of pigmented inks.
2. The display conditions
Harmful, oxidizing gases (e.g. ozone) can damage a print quickly. If you should live for example, at a busy intersection, or if the prints are displayed in a hairdressing salon, where people use bleaching agents frequently, the durability of the prints will be dramatically reduced: the gases attack and fade the images rapidly. Caustic detergents and disinfectants destroy dyes and colour pigments in the same way.
Water and high air humidity, light and heat also shorten the print life; in particular UV rays and excessive heat acting together (e.g. if displayed in the blazing midday sun).
The best protection is framing behind glass; harmful gases cannot attack the image anymore. However, when choosing the frame, ensure that it is made in compliance with archival standards. The same applies to photo albums which also protect the prints, provided that the cardboard and glues are suitable for archiving.
We do not recommend using varnishes or laminates for getting the longest possible print life. These protective films and coatings are recommended only if the prints are exposed to high stress (e.g. rain or mechanical abrasion), and a high level of mechanical protection is required. In the longer term, such coatings or laminating films can change and affect the print beneath.
3. The media
In fact, the durability of the papers of the various reputed manufacturers is very similar. Today’s nanoporous and microporous coatings, which are used for the high-quality papers and films, have only a very small influence on the durability of colours, especially with pigmented inks.
With RC photo papers, the polyethylene layer could become inelastic and cracky after some years, of course. However, this is a rather theoretical issue, as the oldest RC coated (analogue) photo papers date back to the early 70’s, and these now 40 years old photo prints are still perfect. Moreover, the resin coat protects against chemicals/gases that may penetrate and attack from the back of the paper.
Alternatively, fine art papers could be used which contain no plastic, or the opposite, i.e. all-plastic media made of polyester - virtually indestructible - would be an option, too. If archival stability is a must, the paper has to be free of acid and lignin.
Talking about yellowing, the media is key, indeed. Fewer optical brighteners in the paper lead to a warmer base tint and less yellowing with the time. A true Warmtone paper without optical brighteners is the best choice, as no optical brighteners can be destroyed to change the tint of the paper in the turn of the years.
What does all of this mean?
In summary, the inkjet media has only a limited influence on the life of the image; this assuming premium quality media coming from reliable, modern high-tech production (such as all the inkjet media which we have in our BONJET range). The more important factors are the inks (dye / pigment) and the display and storage conditions. And these environmental conditions can and will vary, and only in archives, they are controlled and constant.
We therefore discredit all publications about numbers of years for print life, as these do apply only to specific lab conditions and do not reflect reality.
One can assume that prints may last for 80, 100, or even more years before a visible colour shift occurs; provided the prints are made on a high quality photo paper, fine art paper, or polyester film, printed with high-quality pigmented inks (and maybe even with the latest technology dye-based inks), properly stored in the dark at constant, controlled medium air humidity, room temperature and unpolluted air. Strict archival conditions may even give 200 years of print life, but who can guarantee 100% optimum conditions forever, or even short term?
When reading publications from media manufacturers or independent testing institutes, stating a tremendous stability and durability of the prints, be critical and read the small print. On closer examination, such numbers will not be very realistic, as probably the test conditions have been anything but realistic.