This paper may be of interest to the topic:
Printability and Ink Coating Interactions
That's an amazing paper Mark, thank you for providing that link.
A few interesting aspects:
4.5 Summary
Figure 28. Line width on PVOH-silica coatings with additives.
PVOH-coated samples all presented an excellent colour gamut, which is likely as a result of good film-forming capabilities. The sharpness was also good; however, the coatings suffered from high gloss variation and slow ink drying. With the addition of pigment, a new structure is formed with large pores in and between the pigments, and a macro-roughness generated by the large particles. The inkjet droplets can quickly penetrate into the large pores, and the time for surface wicking is reduced, which is beneficial for the blurriness. However, the macro-roughness promotes bulk spreading in the coarse surface structure; this tends to increase the line width. Finally, the ink ends up within the coating and the colourant is partly shielded by the particles; this reduces the gamut area to some extent. Additives such as cationic polymers and PVP can further improve the print quality. The addition of a cationic additive showed an overall positive effect of gamut area. However, it did not always prevent lateral ink spreading.
It is suggested that blurriness is a surface wicking that is greatly determined by the micro-structure of the substrate [82], while line width is a bulk spreading that is promoted by a hydrophilic substrate and perhaps also by a slow absorption by the underlying substrate and/or ink.Additionally, the paper is dealing most specifically on coatings presumably applying to papers such as gloss, semi-gloss, etc., where even still they are subject to micro-cracks whereby ink can escape through.
Also,
"...The purpose of this work has been to gain an increased knowledge of the mechanisms that con- trol the absorption and the fixation of inkjet droplets on coated papers. The focus has been on printability aspects of high quality
(although not photographic quality) laboratory coated inkjet papers for printers using aqueous-based inks. Coating colours, made from a wide range of com- mercial, as well as non-commercial coating chemicals, have been evaluated mainly in terms of inkjet printability and runnability. Print quality aspects, such as line expansion, blurriness, and colour gamut were analysed and correlated to structural features of the coating layer, as well as to ink composition. It was determined that coatings with pure polymer binders gave an excellent colour gamut and that, with an addition of mesoporous pigments, the print sharpness improved. Moreover, it was also determined that the printability and the binder demand were affected by the pore size, as well as pore size distribution of the pigments...."
The fine art matte papers I'm referring to have unique properties not covered in this study. Yet the principles are there. It appears that chemical composition of the coatings in conjunction with the chemical composition of the inks create the interactions which affect color gamut and all other print quality aspects.
Unfortunately, the study did not delve into the properties and qualities of base components of specific papers.
But definitely an eye-opener for sure. Now if you could find a study on the reactivity of paper substrates to high quality aqueous ink jet coatings, inks and drying times, I would be thrilled.
Thanks again.
Mark