Digital BW, The Print

Paul observed "Keeping the particles separated is mostly done these days with a coating that gives the particles an electrostatic repulsion.  I think this coating oxidizes.  I've seen old Eboni bottles pull in slightly, as if air is being sucked out of them.  I think it is.  The coatings (not the carbon) may be oxidizing.  This would mean the particles would not have the electrostatic repulsion needed to keep them from clumping."

A month or two ago I bought another bottle of Eboni Black from MIS with a "use before" date of 9/4/2013.  The bottle has not yet been opened, and was already significantly "puckered" upon arrival.  Need I be concerned?  


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