Air-laid paper

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Air-laid paper is a textile-like material categorized as a nonwoven fabric made from fluff pulp.[1]

Properties[edit]

Compared with normal wet-laid paper and tissue, air-laid paper is very bulky, porous and soft. It has good water absorption properties and is much stronger compared with normal tissue.

Main characteristics are:

  • Soft, does not scratch.
  • Non-linting, no dust, no static.
  • Strong, even when wet, can be rinsed and reused.
  • Clean, hygienic, can be sterilized.
  • Textile-like surface and drape.
  • Can be dyed, printed, embossed, coated and made solvent resistant.

Manufacture[edit]

Unlike the normal papermaking process, air-laid paper does not use water as the carrying medium for the fibre. Fibres are carried and formed to the structure of paper by air. The air-laid structure is isotropic.

The raw material is long fibered softwood fluff pulp in roll form. The pulp 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. Normally an air-laid paper consists of about 85% fibre. A binder must be applied as a spray or foam. Alternatively, additional fibres or powders can be added to the pulp which can then be activated and cured by heat.

History[edit]

The Danish inventor Karl Krøyer is considered to be the first who commercialized air-formed paper in the early 1980s.[2] Others developed different processes independently at about the same time. A Finnish company United Paper Mills(now UPM-Kymmene Oyj) was one of the companies developing airlaid technology in the 1980s. In the 1980s UPM formed a new company called Walkisoft Oy and also built an airlaid factory to Kotka Finland which started in 1985. Walkisoft built several plants around the world (including the worlds largest airlaid-factory in Mt Holly, NC, USA) in the following 14 years before being sold to Buckeye Technologies Inc. The Walkisoft engineering team, which was responsible for the engineering and R&D of the airlaid machines became known as Buckeye Engineering Finland and from 2002-> as Anpap Oy, a private owned Finnish company.[3] [4]

Applications[edit]

References[edit]

  1. ^ Paulapuro, Hannu (2000). "4". Paper and Board grades. Papermaking Science and Technology 18. Finland: Fapet Oy. pp. 95–98. ISBN 952-5216-18-7. 
  2. ^ Nonwoven Technology Conference 2002 – Ottawa 13-16th May, retrieved 2013-02-13 
  3. ^ http://www.papermakerswiki.com/book/export/html/42
  4. ^ http://www.anpap.fi/company/