Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, Mark MacKenzie 
<mmackenzie@d...> wrote:

> So, this is operating by putting an alkaline material into the 
paper.  
> Neutralization occurs of the current acid radicals.  Perhaps there 
is 
> some residual alkalinity to act as a future buffer.  However, the 
> underlying cause of acidity in the paper remains and in time will 
> produce more, eventually overcoming the buffering abilities of this 
> spray.  Therefore a respray will be needed if you could figure out 
when 
> to do it and still had access to the paper.
> 
> We call this process buffering and it is not the way to go for 
> permanence. 

FIRST OF ALL:

A buffer and an alkaline are NOT the same thing.   An alkaline has 
excess hydroxides (OH)(usually) whereas an acid has excess H+ ions.  
(NB that (typically) combining the two yields HOH (water) plus 
whatever salt results.  (e.g., NaOH+HCl yields HOH + NaCl)   But a 
true buffer resists excess OH **or** excess H+.   For instance, 
CaCO3.  Buffers are never just an acid or a base; a buffer is a weak 
acid or base COMBINED with its conjugate salt.

SECOND:

We have not established that "acid" is even the main cause of paper 
discoloration or color shifts of the inks.   The purpose of the 
Krylon product is to prevent or slow down the deterioration of old 
newspaper or documents.    

I know I sound like a broken record - - - 

(Speaking of broken records, BOTH of my home town teams the Red Sox 
and the Patriots broke records this week.   Te Patriots broke the 
record for most regular season wins formerly held by the 1933-34 
Chicago Bears, and the Red Sox broke the record for most consecutiv 
wins in a playoff series)

 - - - ut we CANNOT talk intelligently on this subject if we don't 
understand the CHEMISTRY.