Tone Value Increase Target Derivation for Uncoated Papers
Deriving uncoated paper TVI targets demands separating optical light scattering from capillary ink absorption using M1 spectral data to set inverse RIP curves.
Uncoated Paper
Fibre Structure
Manufactured paper sheets produced without mineral surface coating layers expose natural cellulose fibres directly to printing inks, moisture, and ambient environmental conditions. Commercial printers select uncoated paper for publications, packaging inserts, folding cartons, and stationery applications that require tactile texture, high ink absorption, and glare-free readability. Substrate properties depend primarily on fiber refined state, internal sizing agents, and mechanical surface calendering.
Fluid Absorption
Paper machines form the web by depositing wood pulp fibers onto continuous wire screens where water drains away to create an interlocking cellulosic sheet structure. Internal sizing chemicals added at the wet end control liquid penetration without sealing surface pores, allowing printing inks to absorb into the fibre matrix. Calendering rolls compress the wet paper web to achieve desired thickness uniformity and surface smoothness while maintaining substrate bulk and stiffness.
Absorption of printing ink vehicle liquids into exposed fibres causes higher dot gain and reduced surface gloss compared to mineral-coated paperboards. Offset press operators adjust ink viscosity and water dampening settings to prevent surface picking and ink show-through on highly porous paper grades. Papermakers select combinations of hardwood and softwood pulps to optimize sheet strength, optical brightness, sheet opacity, and tactile feel for specific commercial end uses.
Grade Boundary
Material classifications distinguish non-coated cellulosic webs from mineral-pigment coated paperboard grades. Utilizing high-quality uncoated paper delivers distinct tactile aesthetic properties while requiring adapted press parameters to control ink absorption.