Mineral Coating Pigment Packing Micro Geometry and Pore Volume Distribution
Pigment micro-geometry and particle packing dictate coat pore volume distribution, controlling ink vehicle absorption rate, print gloss, and coat strength.
Fiber Substitution Economics
Resource Optimization
Financial and material calculation that determines the viability of replacing virgin pulp with recycled or alternative fibres in paperboard production. In modern paper mills, fiber substitution economics guide the blend of raw materials used to achieve specific product specifications at the lowest possible cost. This balance of fibres affects both the variable production costs and the physical properties of the finished packaging board.
Cost Dynamic
Price fluctuations of unbleached kraft pulp and post-consumer recovered paper represent the primary drivers that influence the substitution ratio in any given batch. When the price gap between virgin and recycled fibre widens, mills increase the recycled content to protect their profit margins. However, this shift alters the refining energy required and the dosage of chemical additives needed to maintain paperboard strength.
The overall calculation must account for transportation costs, chemical usage, and the yield loss that occurs during the processing of secondary fibres.
Performance Tradeoff
Higher recycled fibre content typically reduces the tear strength and bending stiffness of the paperboard, which requires a thicker sheet or increased chemical sizing to compensate. This physical change can impact the performance of the board on high-speed folding and gluing lines. Strategic blending allows mills to achieve cost savings while meeting minimum performance thresholds.