High Speed Ink Liquid Interface Dynamics in Ultra Light Coated Virgin Hardwood Graphic Papers
Ultra-light coated virgin hardwood papers demand sub-50nm coat pore radii to balance high-speed inkjet solvent absorption against hardwood fiber swelling.
Precipitated Calcium Carbonate Coating
Synthetic Mineral
Synthesized mineral particles applied to paper and board improve the brightness and opacity of the finished product. The term precipitated calcium carbonate coating refers to the formulation of paper coatings using chemically produced calcium carbonate rather than ground natural limestone. This treatment provides high brightness and controlled porosity for high quality printing surfaces.
Structure Control
Narrow particle size distribution of the synthetic mineral creates an open, highly porous structure with high void volume and excellent light scattering. In precipitated calcium carbonate coating applications, the uniform shape of the particles ensures consistent pore sizes that rapidly absorb ink solvents during high speed printing. This rapid dewatering accelerates ink setting, which helps prevent set-off and smearing in the delivery pile of offset sheetfed presses.
Papermakers can adjust the crystal morphology of the synthetic carbonate to tailor the coating for specific print processes.
Print Performance
Coating chemists often blend this synthetic pigment with kaolin clay to balance the surface gloss and ink drying rate. When a precipitated calcium carbonate coating is formulated incorrectly or used alone, it can lead to high ink absorbency that reduces the gloss of the printed image. Proper blending ensures a smooth, bright surface with the optimal balance of ink absorption and gloss.