Fluff pulp (also called comminution pulp or fluffy pulp) is a type of chemical pulp made from long fibre softwoods. Important parameters for fluff pulp are bulk and water absorbency[1].
More than 90% of the fluff pulps are fully bleached chemical softwood pulps, of which more than 90% are kraft pulps.
The most common raw material source for fluff pulps are southern bleached softwood kraft (SBSK) from slash pine. SBSK from other species and NBSK are also used to make fluff pulp[2].
Thicker fibres are preferred to improve the bulk. The pulp may be impregnated with debonders before drying to ease defibration. Fluff pulp is normally made rolls (reels) on a drying machine (a simplified Fourdrinier machine). The worldwide production of fluff pulps amounts to about 3.5 million tons.
Fluff pulps are used as raw material in the absorbent core of personal care products such as diapers, feminine hygiene products, air-laid absorbent towelling, as such or with superabsorbents and/or synthetical fibres. More than 80% of the pulps are used in baby diapers.
The most demanding application of fluff pulps is in air-laid products, used in serving utensils, various towel applications in homes, in the industry and in hospitals. Fluff pulp for air-laid products are defibrized in a hammermill. Defibration is the process of freeing the fibres from each other before entering the papermachine. Important parameters for dry defibration are shredding energy and knot content.