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Summaries from TAPPI Journal, Paper360º May/June 2024

Optimization of optical coverage of board surfaces with assessment of light scattering and absorption using mineral as a coating component, TAPPI Journal June 2026

ABSTRACT: One of the primary functions of mineral inclusion into paper or paperboard is to improve the optical performance of the substrate. A coating may be applied to a sheet in order to cover a dark base, to improve the sheet opacity, to give the correct smoothness and gloss, or to give a suitable surface on which to print. The brightness of a pigment has long been used as a guide for pigment choice in paper and board. However, the measured paper brightness is a function of color and light absorption (K) of the coating and base and the light scattering (S) within the sheet resulting from interfaces with different refractive index. The optical performance can be quantified by measuring the S&K coefficients as described by the Kubelka-Munk model/theory in a filled or coated paper sheet. In coating, this is often assessed as a function of coat weight, and the corresponding physical sheet properties are assessed at the same time; for example, the correct gloss, smoothness, point-to-point uniformity, and printability. The optical performance in the sheet is often not directly related to the pigment brightness, but is largely a function of the particle packing within the sheet and coating layer. In the first and second main sections of this work, respectively, we show how S&K calculations from the Kubelka- Munk equations can be used in coated sheets to determine the optical performance and how this can be used as a predictive tool for the final sheet performance. This is presented for base sheets with different starting brightness. The third section of this work focuses on how mineral combinations in coatings can be used to improve the light scattering and consequently the optical performance of the board. We include theoretical considerations and then finally share a case study for improvement on the optical properties of recycled board.

Modeling and Simulation of Pulp and Paper Quality Characteristics Using Neural Networks, 2001 TAPPI Peer-Reviewed Papers / Solutions! October 2001 / VOL. 84: NO. 10 [01OCTSO59.pdf]

Modeling and simulation of pulp and paper quality characteristics using neural networks, Solutions!, October 2001, Vol. 84(10)

Last Word: Rumors and reality, SOLUTIONS! [01OCTSO80.pdf]

Rumors and reality, Solutions!, October 2001, Vol. 84(10)

PEOPLE ON THE MOVE, October 2001 SOLUTIONS! [01OCTSO28.pdf]

People on the move, Solutions!, October 2001, Vol. 84(10)

Color and Gloss of Whey-Protein Coated Paperboard, 2001 TAPPI Peer-Reviewed Papers/ Solutions!, October 2001 / VOL. 84: NO. 10 [01OCTSO58.pdf]

Color and gloss of whey-protein coated paperboard, Solutions!, October 2001, Vol. 84(10)

COMPANY PROFILE: Stora Enso: coming to America, October 2001 SOLUTIONS! [01OCTSO41.pdf]

Stora enso: coming to america, Solutions!, October 2001, Vol. 84(10)

TECHNOLOGY FOCUS: Aspen BCTMP, Proven performance, November 2001 SOLUTIONS! [01NOVSO28.pdf]

Aspen Bctmp: Proven performance, Solutions!, November 2001, Vol. 84(11)

NETWORKING: Sticks and stones break more than bones, SOLUTIONS! [01SEPSO72.pdf]

Sticks and stones break more than bones, Solutions!, September 2001, Vol. 1(1)

MANAGEMENT FOCUS: Engineering in the Age of Optimization [01SEPSO68.pdf]

Engineering in the age of optimization, Solutions!, September 2001, Vol. 1(1)