Digital BW, The Print

David,

I think the biggest and most misleading factor is the word "archival" misapplied to "fade resistance" when describing papers and inks. These are two mutually exclusive terms. One having nothing to do with the other. People pick and choose papers without thinking twice which might be a more archival solution than the other. Everyone is wrapped up in ink longevity without realizing the results do not take into account anything other than the ability of the paper to retain its whiteness during the endurance of the light stability testing but do not take into account the ability of the paper to last over time.

For example, IRIS dye based prints on uncoated Somerset Satin paper are very archival - but they can fade very quickly. They have a low light stability rating of a few years but can outlast chemical photographic processes when kept in archival storage conditions which include limited exhibition. A much more fade resistant chemical print will not outlast an IRIS dye based print on uncoated Somerset in archival storage conditions. Epson Ultrachrome inks on newspaper printing paper is not archival, but could test in Wilhelm conditions to be very, very fade resistant - perhaps centuries as a rating - while the paper will deteriorate in practicality within a few years. On the other hand, Aardenburg light stability testing will pick up the quick discoloration of the newsprint where WIR testing would not. I hope I drew two comparisons that make sense in regards to fade resistance and archival, so that you can separate them because they are at the heart of paper selection and coatings.

Ideally, an uncoated paper, and an unsized paper (with the exception of starch sizing) would be ideal and the only papers that seem to retain enough ink to be acceptable are japanese fiber based papers - but they are very "buff" and very thin. The dMax is lower than most would appreciate. I print on a lot of uncoated japanese fiber papers and I also print on uncoated japanese kozo/cotton blends by using heated printers to warm the paper and allow greater dMax through evaporating the inks quickly. But, its not the cup of tea that many photographers would appreciate. 

The reason for using these is not fading of the inks, but historical longevity of the actual object. Plus some of my clients really love japanese handmade papers and the way ink reacts with it. This type of paper used in printmaking has existed for centuries already and the paper has been designed to last centuries by papermakers who pass on the skill in generations of families making for all practical purposes the same sheet, from the same spring water, and the same raw grasses for centuries. Putting a typical inkjet coating on it - changes the game. Now it becomes the coating rather than the paper that we must rely on to not absorb pollution at a higher rate (which is what a coating in effect is designed to do.)

Western papermaking in terms of uncoated materials also has a long history - but not nearly as long as japanese paper making. But for inkjet - we need coatings. What these coatings do is to absorb moisture (ink)  but unfortunately will continue to absorb over time and therein lies the 300lb gorilla. Is it better or worse than gelatine? Check back in a few more decades...You will need to however, rely on conservators not light stability testing to learn about coatings and their archival life. Two different subjects that you really need to wrap your head around. The MOMA and the Met have conservation departments that are accessible and you can visit to ask questions about media and the atmosphere in order to understand what you need to protect against. So little is published on this subject as it pertains to ink jet other than its propensity to absorb OZONE. The making of an inkjet coating, if that is what you are involved in might look back historically to the use of starch and gelatine rather than some of the more inkjet oriented materials.



Wilhelm and Aardenburgh have some specific differences which you can read about in their own words as it pertains to the differences in their light stability methods.

You can go read about Wilhelm's testing procedures directly on WIR website as it relates to Aardenburh philosophy.

www.wilhelm-research.com/istar/WIR_IST_2007_09_HW_DS.pdf 

because it is very complimentary to the new methods Mark developed. He designed the proposed iStar metric in the WIR article, though the method was not adopted at WIR - or at least was not at the time. Perhaps WIR has a new testing procedure around iStar. Mark can say...

and you can read about Mark's methods directly on the Aardenburg website which you should join in order to support him. 

- read for yourself and choose.




Jon Cone
Piezography


 



--- In DigitalBlackandWhiteThePrint@yahoogroups.com, David Kachel <david@...> wrote:
>
> 
> On Apr 8, 2010, at 9:30 AM, piezobw wrote:
> 
> > Roarke is correct in wanting to use papers that do not have inkjet coatings if his concern is to print on papers that will last as long as possible.
> 
> 
> Where can I find a reference source that expands on this? I had already come to the conclusion on my own that inkjet coatings could be a problem just because the manufacturers don't talk about them and are reluctant to tell you what's in them (one just flatly refused to provide an MSDS which is a Federal no-no), but I would like to know why these coatings are a potential problem.
> 
> Also...
> 
> On a semi-related topic: I have seen "Wilhelm years" mentioned here several times and could use a reference to an explanation. Apparently Wilhelm's tests are being "translated" into some other number that in some cases seems to imply that prints are virtually turning to dust as they issue from the printer <grin>. Anyway, it makes it difficult to compare the numbers for some of the B&W ink sets discussed here to Wilhelm's numbers for OEM inks. The implication that Wilhelm's results are overly optimistic leaves me with no point of reference.
> 
> 
> David Kachel
> 
> 
> 
> [Non-text portions of this message have been removed]
>