Fluff pulp (also called comminution pulp or fluffy pulp) is a type of
chemical pulp made from long fibre
softwood
Scots Pine, a typical and well-known softwood
Softwood is wood from gymnosperm trees such as conifers. The term is opposed to hardwood, which is the wood from angiosperm trees. The main differences between hardwoods and softwoods is that the s ...
s. Important parameters for fluff pulp are bulk and water absorbency.
History
Fluff pulp was first developed for use in disposable
sanitary napkin
Sanitation refers to public health conditions related to clean drinking water and treatment and disposal of human excreta and sewage. Preventing human contact with feces is part of sanitation, as is hand washing with soap. Sanitation systems ...
s.
Kotex's first advertisement for products made with wood pulp (Cellucotton) appeared in 1921.
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/ref> Disposable diaper producers also were early to convert to fluff pulp because of its low cost and high absorbency. Normal usage of fluff pulp in a diaper was about 55 percent. In the 1980s started the commercialization of air-laid paper
Air-laid paper is a textile-like material categorized as a nonwoven fabric made from fluff pulp.
Properties
Compared with normal wet-laid paper and tissue, air-laid paper is very bulky, porous and soft. It has good water absorption properties an ...
, which gave better bulk, porosity, strength, softness, and water absorption properties compared with normal tissue paper
Tissue paper or simply tissue is a lightweight paper or, light crêpe paper. Tissue can be made from recycled paper pulp on a paper machine.
Tissue paper is very versatile, and different kinds of tissue are made to best serve these purposes, whi ...
. Also in the 1980s started the use of superabsorbents in diapers and reduced the need for fluff pulp and is now down to 15 grams or even less. The demand of the pulp in diapers has gone from being the absorbent of liquid to giving the products dry and wet strength The wet strength of paper and paperboard is a measure of how well the web of fibers holding the paper together can resist a force of rupture when the paper is wet. Wet strength is routinely expressed as the ratio of wet to dry tensile force at brea ...
.
Manufacture
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 loblolly pine
''Pinus taeda'', commonly known as loblolly pine, is one of several pines native to the Southeastern United States, from East Texas to Florida, and north to southern New Jersey. The wood industry classifies the species as a southern yellow pine. U ...
. SBSK from other species and NBSK are also used to make fluff pulp.Fourdrinier machine
A paper machine (or paper-making machine) is an industrial machine which is used in the pulp and paper industry
to create paper in large quantities at high speed. Modern paper-making machines are based on the principles of the Fourdrinier Machi ...
). The objective of the drying/sheeting operation is to produce a uniform sheet (paper density
Paper density is a paper product's mass per unit volume. The density can be calculated by dividing the grammage of paper (in grams per square metre or "gsm") by its caliper (usually in micrometres, occasionally in mils).
The " ISO 534:2011, P ...
, moisture, and strength) to the converting operation. The pulp may be impregnated with debonders before drying to ease defibration.
The worldwide production of fluff pulps amounts to about 3.5 million tons.
Applications
Fluff pulps are used as a raw material in the absorbent core of personal care products such as diaper
A diaper /ˈdaɪpə(r)/ ( American and Canadian English) or a nappy ( Australian English, British English, and Hiberno-English) is a type of underwear that allows the wearer to urinate or defecate without using a toilet, by absorbing or c ...
s, feminine hygiene products, air-laid absorbent towelling, as such, or with superabsorbents and/or synthetic 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 is defibrized in a hammermill. Defibration is the process of freeing the fibres from each other before entering the paper machine. Important parameters for dry defibration are shredding energy and knot
A knot is an intentional complication in Rope, cordage which may be practical or decorative, or both. Practical knots are classified by function, including List of hitch knots, hitches, List of bend knots, bends, List of loop knots, loop knots, ...
content.
References
Papermaking
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