Digital BW, The Print

----- Original Message -----
From: "Dan_Honemann" <dan_honemann@...>
To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
Sent: Friday, September 06, 2002 10:39 PM
Subject: [Digital BW] Re: UltraChrome 100 Hr Fade test


> Paul,
>
> The UC inks may last 75-100 years, but the Enhanced Matte paper will
> begin to yellow at 30 years, at least according to Royce Bair at
> inkjetart.com; I quote him here:
>
> "The Enhanced Matte image permanence drop was NOT in going from the
> roll version to the sheet version (not a coating difference issue)
> The 30 years vs. 75 years (with UltraChrome inks) and the 30 years
> vs. 100+ years (with the Archival Inks) is due to paper YELLOWING.
> Within about 30 years, both the roll and sheet versions of the
> Enhanced Matte paper will yellow due to the paper's slightly acid
> pH.  The image itself, will not start to show noticeable fading
> until about 75 years (UltraChrome) or about 100+ years (Archival).

Dan,

Thanks for the info on the "life" rating. The line between paper and image
permanence tends to get blurred. The yellowing in the Archival Matte and
other papers with optical brightening agents is due to the OBA's loosing
there ability to fluoresce. Robert Rex of Crane paper posted information on
this quite some time ago. Once the OBA is exhausted and has yellowed it is
stable and does not appear to effect paper life. The effect of OBA's on
image permanence is not known but obviously a yellowing of your highlights
is not a desirable effect. Keep in mind that most of the top silver fiber
papers seem to use some OBA's too.

Martin Wesley

(snip earlier)