Dye based ink fade resistance of 200 years?

[pharmacist]

Hi Simon,

those manuscripts on parchment and acid free papers are written with iron gall ink, which will last for centuries, if the formula is good (not to much iron, or the paper will be destroyed). Therefore I always use my home brewed iron gall ink formulated by the german (yes indeed !!!) "Urkunde Spezifikationen" to sign my important documents. The only way to remove the ink from the paper is actually destroying or burning the paper...

 

[PhotoSci]

Broadly speaking, two things govern the stability of a basic inkjet colorant: the stability of the molecule itself and its environment, which includes not only the solvent, the receiver matrix, etc., but also the morphology, that is whether it is a more or less isolated molecule (dye-based colorants) or an agglomeration of molecules (like a pigment).

One may also ask "stable towards what?" More on that in a moment.

Given similar chemical structures, pigments are likely to have greater stability than the corresponding dyes. However, it is entirely possible to have a pigment made from an inherently low stability molecule that would result in a lower stability ink than a dye ink made from a high stability molecule.

That said, this is unlikely to happen as manufacturers choose the best molecular stability they can get subject to other attributes (color gamut, dry time, water resistance, etc.). So a good rule of thumb is that pigmented inks are likely to be more stable than dye-based inks.

But stable towards what? For a long time, one of the best known contract testing labs was testing only towards light stability, resulting in some truly embarrassing predictions when the product's ozone stability was simply awful, and prints faded from ozone exposure long before light could get them. (Even after this lab started to include ozone testing in its repertoire it coyly omitted ozone ratings with an eternal "Test in Progress" rating for its contract customers whose products did not do well in ozone tests.)

Other factors that are important are thermal stability (sometimes called dark stability, though it occurs in displayed pictures as well) and humidity resistance. The first company to insist that all four factors be tested was Eastman Kodak who had been doing such tests on its other imaging products for years (silver halide prints are not usually subject to ozone failure).

It's also important that all four factors be kept in balance if one wants to predict real world lifetime. Use too high an assumed light level (such 450 lux) with too low an assumed ozone level and you might predict that a displayed print with good light stability would last much longer than it really would, sucumbing first to ozone-induced fade.

So back to the dye-based ink that is supposed to last 200 years in albums and 100 years under glass, presumably with light exposure. Yes, it's possible. But unless the company is a well-known one whose image permanence lab is unlikely to publish bogus results, I'd ask to see both the data and the methods of testing. As a customer, you have every right to ask--nay, demand. (The large companies discuss their test methods both in their own literature and in papers given at conferences sponsored by the Society for Imaging Science and Technology.)

And when in doubt, pick pigmented inks from a well-known manufacturer when image permanence is a primary factor. Original manufacturer's inks may cost more (though at least one inkjet printer company is marketing its own pigmented inks with excellent stability at a price very competitive to off-brand inks), but you'll be glad you did for pictures you want to have last a lifetime.

 

[nche11]

Canon advertises that its dye inks will last 70 years if printed on Canon premium grade paper. But realistically how long will it really last? Probably a few months if exposed to sunlight behind a window glass. A few years is likely though in a file folder.

 

[The Hat]

I think the manufactures just make that claim to deter most of us from buying bulk and knowing we wont be around to prove them right or wrong, its a pity the same manufactures dont sell bulk ink to high users maybe that would solve a problem. O well I think things will just keep fading away..

 

[leo8088]

Dye based inks are better than pigment based inks for printing photos. They do better especially on glossy papers. The traditional Kodak photographic paper or films are coated with color dye couplers before printing. Once exposed to images and developed in photographic chemicals the dye couplers form dye images. This old traditional technology produces photos with color dyes that can last up to 30 years. Why didn't Kodak use color pigments instead of dyes? This old technology is still the most popular one for printing photos today.

 

[mikling]

If you've used pigment ink printers as well as dye printers, you will come to appreciate the differences between the two. Pigments excel in showing subtlety of tone that dye ink printers have a hard time matching, even the Canon Pro 9000 cannot compete against pigments in this area. However when vibrancy and punch is called for, the Pro9000 will step right up and deliver and pigments cannot compete.

When each is used should depend on the image and atmosphere you want your image to convey. This is part of the artistry of photography.

The latest photoprinters introduced by Kodak uses pigment ink.

The best dye ink produced thus by any manufacturer far is GENUINE Epson Claria ink. I stress GENUINE. Any third party bulk ink that claims equal life to Claria should be asked to back up their claim. Forget the UV resistant blah blah. It's just that. It is estimated that Claria might have about half the life of genuine pigment inks and for a dye ink, that is darn good....but only if you buy the genuine Epson cartridge.

 

[leo8088]

If you've used pigment ink printers as well as dye printers, you will come to appreciate the differences between the two. Pigments excel in showing subtlety of tone that dye ink printers have a hard time matching, even the Canon Pro 9000 cannot compete against pigments in this area. However when vibrancy and punch is called for, the Pro9000 will step right up and deliver and pigments cannot compete.

Dye based inks simply produces wider color space than any pigment inks. But the dye color space is not inclusive of that of pigment inks. Pigmant ink does produce its own set of unique colors that are brilliant and not matched by dye inks. However, dye inks printed on glossy photo paper is the best that resembles closest to real images which is not matched by pigment inks.

I can print absolutely beautiful photos by using my cheap ip4300. I have tried many lower end Epson printers with DuraBrite pigment inks. There is absolutely no match. I have seen maybe a hundred or more of large prints (demo photos) in a professional photographic supply store full of professional printers. I have been there a dozen times in a year. I don't have all those printers so I made the conclusion by seeing those demo prints. The prints out of Pro9000 are absolutely better photos. Epson professional printers do produce excellent color prints. But in terms of photo quality Canon Pro9000 wins. I am not saying Epson prints are bad. They are highly desired for a different reason.

 

[mikling]

" I am not saying Epson prints are bad "

Hey Epson is not the only game for pigments, HP and Canon also makes excellent pigment based printers as well. They do this because there's a reason pros demand these printers and most eschew dye printers.

Most pros acquire Epson pigment printers because it is Epson who has and is currently leading in this market segment.

Color is now vanilla...... The younger generation are quickly discovering the art form of B&W. Here you are best served with a printer that can print carbon based pigment ink. That gives you the 200+ years fade resistance and who's going to be around to check it.

 

[The Hat]

mikling wrote:
" I am not saying Epson prints are bad "

And needier am I

I have a Canon all pigment ink printer and the colour is second to none not to mention the quality of the B&W prints..

 

[PhotoSci]

Inkjet Master Wrote: The traditional Kodak photographic paper or films are coated with color dye couplers before printing. Once exposed to images and developed in photographic chemicals the dye couplers form dye images. This old traditional technology produces photos with color dyes that can last up to 30 years. Why didn't Kodak use color pigments instead of dyes? This old technology is still the most popular one for printing photos today.

Pigments are composed of dyes, the isolated colorant molecules; the difference is their physical state. Pigments are agglomerations of dyes and can be produced by various methods, such as controlled precipitation. They are then dispersed in the inkjet ink.

Dye-forming couplers coated in traditional silver halide films and papers are more or less isolated molecules, usually suspended in what is called a coupler solvent. If you react a coupler with a developer (actually an oxidized developer), it will form an isolated dye molecule and will have no impetus to aggregate.

You cannot coat the dye-forming coupler as an aggregated molecule because that will prevent the developer from reaching all the molecules inside the aggregate and forming dye. Thats the reason neither the films and papers from Kodak or other photographic companies contained aggregated dyes.

(There is a second issue: you also dont want particles in the film that are big enough to scatter light when you take or print an image or you would lose sharpness, but thats a moot point here).

Because the dyes in silver halide products must be formed in the film or paper from colorless precursors, the nature of the dyes (or dye classes) are limited (technically they are all azomethine dyes), and image stability is just one of the attributes that must be optimized. Ink jet dyes, being pre-formed, have a wider array of dye classes open to them.

That said, the image lifetime of modern silver halide print materials is far in excess of 30 years. For example, Kodak Professional Ultra Endura paper has light stability of over 100 years in ordinary home display environments. Album stability (and over 95% of prints spend most of their time in dark keep conditions) is well over 200 years. Further, silver halide prints are largely unaffected by pollutants like ozone which can rapidly degrade some ink jet materials.