Digital BW, The Print

One of the main problems with papers coated for pigmented inks, is
they tend to be "micro porous". Unless this micro porous coating is
sealed after printing, it is vulnerable to atmospheric degradation.
This includes ozone, which can quickly oxidize dyes and degrade
pigments too!

Of course we are also faced with the various optical brightners used.
Some will actually turn yellow, as they fade. 

When RC substrates became prevalent in B&W and color papers 25-30
years ago, there was concern about how archival the RC coated base
was. Early batches of papers were notorious for  exhibiting a
"cracked" look when exposed to UV. But of course, Kodak in the 70's
didn't think a print needed to last longer than 5-10 years. ;-)

Arches paper, of course uses a gelatin tub sizing, which could be
considered a "coating". But this paper has been around for a long
time, and seems to have accumulated a pretty good track record. The
same can not be said for the majority of the inkjet coated papers out
there. And the coatings and processes seem to change all the time. It
seems the only papers with consistency for the last 10 years come from
Crane and that German company. 

It will be interesting how the new baryta papers stack up. I like the
look of the Ilford paper. I just wish they had used a rag paper base,
but I guess the new premium buffered wood pulp papers should be pretty
good for 50-100 years?

John Nollendorfs

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "pr_roark"
<pr_roark@...> wrote:
>
> Bill Storm" <stormband1@> wrote:
> 
>  
> > ... ANSI IT9-5 standards committee ...
>  
> > Based on some of the findings the committee identified it 
> > would be fair to believe any laminated or multi-layered 
> > media is likely to have issues over time. ...
> 
> Even the matte papers have an inkjet receptor coating on them.  Do 
> you think this type of coating would also be at risk?
> 
> I've assumed that at least some would want to avoid even these 
> coatings.  So, Arches Hot Press water color paper (un-coated) has 
> usually been one of the papers I test and profile.  For display sizes 
> the new 1.5 pl printers can do a fairly smooth print on these.  If 
> there were a 24" 1.5 pl printer, I might actually be tempted to 
> replace my old 7500 with it.
> 
> On a related issue, Wilhelm does give some information on paper 
> longevity in the "Album/Dark Storage" column of his reports.  See, 
> for example column 4 in http://www.wilhelm-
> research.com/epson/11880.html   At the very least when there is too 
> much yellowing, that affects the end point of the test.  
> 
> I've speculated that one reason Wilhelm does not get further into age 
> testing is that, according to some conservation types I've 
> communicated with, doing such tests is much more difficult or 
> uncertain than fade testing.
> 
> What procedures did your ANSI IT9-5 standards committee use for 
> accelerated age testing?
> 
> Paul
> www.PaulRoark.com
>