COLOR Fading

[sunilhegde]

Hi,
We printed a Cover by offset printing. Color used Pantone 138C. This color faded after eight months. The client is asking for explaination.
Though i know that some colors are pro to fadeing under certain conditions, i need come technical write up on this issue of color fading.
Can anyone please provide be with such write up or extract from some technical reference.
Thanks,
Sunil

[gordo]

You could start here:
Quality In Print: Fade to black - ink permanence Part 1 of 2

and then go here:

Quality In Print: Fade to black - ink permanence Part 2 of 2

best, gordon p

[sunilhegde]

Hi Gordon,
Thanks, for this useful link. It has been of really useful.

Thanks,
Sunil

[michaelejahn]

Go to the search tool at Pantone;

Search

in the "article" tab - search for the term "fade"

-- because paper yellows with age and ink fades, the appearance of a printed color will change over time

The color you mentioned - Pantone 138 - an slightly brownish orange color and probably is made by using Azo compounds - this is what the industry uses to make magenta and orange colorants - dinitroaniline orange, orthonitroaniline orange - Lithol Rubine BK some of these compounds inks are not very colorfast - that is, they fade.

Gordon's excellent article suggests one approach that might be seriously considered - Varnishing and lamination of presswork will generally improve its lightfastness.

Best of luck with that, and be sure to point out the faded food posters in most Asian restaurants front windows !

[jonprintz]

You could start here:
Quality In Print: Fade to black - ink permanence Part 1 of 2

and then go here:

Quality In Print: Fade to black - ink permanence Part 2 of 2

best, gordon p

This is interesting reading. I will re-read again but I've found a couple of instances that contradict my experiences with testing light fast inks.

Ink vendors all claim that their product is lightfast and will out last other brands. The reality is that not all ink companies that sell lightfast inks have an internal testing program or machine to verify lightfastness of their product. Every company is different and a few stars definitely shine brighter than others. The typical ink vendor is not the best source of information regarding fade resistance.

Adding UV coatings with UV inhibitors will increase lightfastness for a longer period of time vs. uncoated but in a situation where weathering is needed adhesion failure to the stock will occur much quicker than an uncoated piece in accelerated testing. The substrate is a big factor in longevity for fade or weathering as is the UV coating that is used. It is all about the total combination vs. the individual components.

The blue wool scale is a good guide but the only true way to know the lightfastness of any ink is to test it yourself....out of doors and in an accelerated testing machine. I have tested several sets of inks that were rated by their manufacturer to high bws ratings yet fell far short of my expectations for fade resistance. Generally, in my experience, when a vendor refers to the bws he is short on fade testing experience with his inks.

The formula's that compare hours in a testing machine to months of outdoor exposure should only be used as very general guides. Every region is different and weather patterns are constantly changing. Some charts do not take into account the stronger summer sun months.

The end use environment for the specified time is the best test. If that can be duplicated and compared to a well documented accelerated test then life expectancy of the piece in the field can be understood and planned for in subsequent accelerated testing of the same or similar combinations of materials.