Sir,
Pigment particle size has very little to do print quality because a quality ink maker/manufacturer/formulator will take care of the variations that are inherent to the pigments used in printing inks.
I will give a couple of examples:
1) Process Blue or PCN Blue Pigment 15:1. The phthalo blue particle size is rather large and tends to be more irregular versus the mass of pigments used. To overcome this, extra dispersing and grinding activity is commonly done during the manufacturing process. Additionally the formulator will use extra wetting mechanisms such as an alkyd or drying oil that gives the best opportunity to completely encase or 'wet' the pigment from an agglomerate form.
2) Process Yellow or AAA Yellow Pigment 12. This pigment imparts qualities of shortness into generic type formulas, just using standard vehicles. Many times a printer will find a 'proc yellow' backing away from the fountain barrel, because of an improperly formulated ink from the vendor. A good experienced ink formulator will reconstruct the recipe using 'longer' vehicles to overcome the shortness ratio.
The bottom line is that all printing ink should be properly formulated for a given piece of equipment and if a problem arises a live body, boots on ground person should be available 24-7-365. Not an 800# or a rolly polly salesman.
Printers should not need to have to worry about pigment properties or really any ink property, but it is good if they have some education into the subject when called upon from their ink supplier. If you cannot get this through classroom seminars at you printing plant, I would suggest you shop for a quality, experienced technical person who has the knowledge how and can offer periodic training sessions for you, the printer. I understand this paragraph somewhat contradicts itself, but both thoughts I have presented here are valid.
D Ink Man
