Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Clayton Jones" 
<cj@...> wrote:
>
> >>So of the two Hahnemuhle papers, the one with OBAs outlasts the  
> >>"purer" paper.
> >>Am I misunderstanding something?
> 
> >I don't think the OBAs is the significant difference between the
> >papers.  I've had Harman FB Al in a south facing window since last
> >summer and the paper base has moved from cool to neutral but doesn't
> >seem to have other negative effects.
> 
> In addition, there are different types of OBAs.  We use the term
> broadly, but when I did some research on the subject for an article
> (#5 at the link below) it was pointed out to me that OBA technology is
> 

In general, if you are chasing permanence then stay away from using any 
paper using OBA's.  They are not permanent, as they change so will the 
presentation of your print.

OBA's are introduced into some papers at various stages.  Those that 
are in the paper pulp tend not to move around much but will still fade 
and degrade and change ? into other chemicals which may or may not 
further degrade the image base.

Other OBA's are added in the ink receptor coating.  

We have found that some of the textile products we use for attaching to 
textile artifacts for identification purposes have OBA's of the latter 
type.  These can not only rub off onto the artifact but also transfer 
in solution form if there is an accidental wetting.

We have put a call back through out our museum system prohibiting the 
use of these textiles.  When contacted, some of the manufacturers or at 
least the wholesalers did not know anything about the addition of OBA's 
to their product.

For us, simply looking at a suspect material under UV light shows 
immediately whether OBA's are present.  I will try some of our 
photodocumentation inkjet paper (Lyson) at the museum and see.  But 
almost any UV source (forensic type LED flash light) should work.

Regards

Mark