Ismo Nousiainen, CEO of Metsä Fibre, the world’s leading bleached softwood market pulp supplier, presented research and mill trial results making the case that northern bleached softwood kraft pulp — NBSK — remains an essential and performance-critical component in through-air-dried, or TAD, tissue production. TAD is the manufacturing technology behind premium tissue products — high-end bath tissue and kitchen towels — in which hot air rather than mechanical pressure dries the tissue web, producing significantly higher bulk, softness, and absorbency than conventional wet-pressed grades. It is the most demanding end use remaining for softwood pulp as hardwood substitution continues across other grades, and the segment where softwood’s functional properties are most clearly differentiated.

Ismo Nousiainen

Nousiainen provided context on the company before moving to the trial results. Metsä Fibre operates four pulp mills in Finland — which the company designates bioproduct mills, reflecting a commitment to fossil-fuel-free operations and full utilization of all process side streams — with a combined pulp capacity of 4 million tonnes. The most recent addition, started in 2023 at a capital cost of 2 billion euros and a capacity of 1.5 million tonnes, represents the latest iteration of that model, with side streams converted to biogas and biomethanol for biofuel, and a new lignin product currently in the demonstration phase. The company is also exploring the capture of CO2 from its flue gases for e-methanol production — a development that connects to the carbon capture themes discussed by other speakers at the conference. Metsä Fibre’s four sawmills, with a combined capacity of 1.9 million cubic metres of sawn timber, are tightly integrated with the pulp mill operations — sawmill chips feed directly into pulp production, and excess heat from the pulp mill flows back to the sawmill, capturing synergies across the full wood raw material chain. While production is anchored in Finland, the company operates sales offices in Wiesbaden, Shanghai, and — in a development not yet reflected in the company’s current materials — New York, reflecting North America’s growing strategic importance to the business. On sustainability, Nousiainen highlighted the company’s MetsäPlus forest management method, which applies harvesting criteria more stringent than FSC certification with the explicit goal of actively improving biodiversity in harvested areas rather than simply maintaining it.

Metsä Fibre’s pulp offering spans softwood, hardwood, and high-yield grades. Within softwood, two primary NBSK grades are offered — Metsä Pine, the company’s standard northern NBSK providing strength across applications, and Metsä Strong, a tailored grade with superior tensile properties developed for applications where reinforcement performance is most critical. The high-yield grade delivers stiffness properties suited to printing, writing, board, and tissue applications. Approximately 35% of the company’s NBSK is consumed in the tissue sector, with printing and writing accounting for a significant additional share, supported by Metsä Strong’s tailored performance profile for that end use. Looking ahead, Nousiainen acknowledged that printing and writing will continue to decline, and that softwood substitution by hardwood is an ongoing structural trend — one he said is occurring even within tissue. TAD tissue is where softwood’s position remains most durable, not by default but because of performance properties that hardwood has not been able to match in that application.

The functional case rests on what softwood fibre does in a TAD furnish that hardwood cannot readily replicate. In premium kitchen towel grades on TAD machines, the softwood share of the furnish typically exceeds 50%, making NBSK quality a decisive factor in end product performance. Nousiainen framed softwood’s role not as a commodity input but as a functional component — providing the structural backbone needed to achieve strength, runability, and durability while enabling bulk and softness targets. The performance requirements differ by grade. In toilet tissue, NBSK must deliver controlled strength, softness, hand feel, bulk, and low basis weight. In kitchen towels, the demands are more exacting — durability, wet strength, and high tensile performance are increasingly critical, and the contribution of softwood fibre correspondingly more pronounced. Consistent fibre properties matter across both grades, supporting production efficiency at the base paper stage, reducing disturbances in converting, and delivering predictable performance in the finished product.

The trial results Nousiainen presented showed Metsä NBSK matching the performance of leading market reference pulps in TAD processes even at reduced softwood inclusion rates, while delivering measurable improvements in energy efficiency. For tissue producers managing cost pressure, the practical implication is that optimizing around Metsä NBSK can allow producers to reduce softwood content and refining intensity without sacrificing — and in some cases while improving — end product quality. Kitchen towels produced with Metsä NBSK in the trials were stronger than many market brands despite a lower softwood share in the furnish.

In the Q&A, moderator Kelly McNamara asked where NBSK delivers the greatest value in TAD production given the cost pressures tissue producers face. Nousiainen pointed to end product quality and machine runability as the two primary value drivers — consistent pulp quality produces a uniform base paper, and a uniform base paper supports efficient converting. On how softwood’s role in tissue might evolve as producers push softness and strength targets further, Nousiainen said the direction is toward increasingly tailored grades for specific applications — moving away from a general-purpose NBSK toward grades optimised for tissue and adjacent segments. “No longer a commodity,” McNamara observed. Nousiainen agreed.

Drafted with the assistance of digital tools to streamline the process.