Skip to main content

Official Journal of the Japan Wood Research Society

Journal of Wood Science Cover Image

Ultrasonic treatment to improve the quality of recycled pulp fiber


The effect of ultrasound on the quality of recycled fibers was investigated. Ultrasound was applied to recycled pulp fiber suspension before ink removal by conventional flotation. The ultrasonic treatment induced an increase in the sedimentation volume of the fiber, which implies that the flexibility and bulkiness of the fiber increase. The water retention value of the ultrasonically treated fiber recovered from the loss caused by the recycling. These facts are due to a beating effect of the treatment. The paper sheets prepared from the ultrasonically treated fiber suspension showed higher sheet density, tensile strength, and brightness than that from an untreated fiber suspension. The process, which consists of ultrasonic treatment for 1 min following flotation deinking, requires about 1.4 times as much energy as the conventional flotation deinking process, but it induced 20% improvement in brightness. The results indicate that the ultrasonic treatment is effective in improving recycled fiber quality.


  1. 1.

    Chang H-M (1998) Future fiber supply trend and research needs in the pulp and paper industry. '98 Cellulose R&D. Cellulose Society of Japan, Kyoto, pp 1–4

    Google Scholar 

  2. 2.

    Turai LL, Teng C-H (1978) Ultrasonic deinking of waste paper. TAPPI 61(2):31–34

    CAS  Google Scholar 

  3. 3.

    Naimpally AV (1981) Note on use of ultrasonics for deinking paper. Appita 35:242

    CAS  Google Scholar 

  4. 4.

    Snyder BA, Berg JC (1994) Liquid bridge agglomeration: a fundamental approach to toner deinking. TAPPI J 77(5):79–84

    CAS  Google Scholar 

  5. 5.

    Norman JC, Sell NJ, Danelski M (1994) Deinking laser-print paper using ultrasound. TAPPI J 77(3):151–158

    CAS  Google Scholar 

  6. 6.

    Scott WE, Gerber P (1995) Using ultrasound to deink xerographic waste. TAPPI J 78(12):125–130

    CAS  Google Scholar 

  7. 7.

    Bajpai P, Bajpai PK (1998) Deinking with enzymes: a review. TAPPI J 81(12):111–117

    CAS  Google Scholar 

  8. 8.

    Johansson B, Ström G (1998) Surface chemistry of flotation deinking: effect of various chemical conditions on ink agglomerate character and floatability. Nord Pulp Pap Res J 13(1):37–49

    CAS  Article  Google Scholar 

  9. 9.

    Wise EM, Arnold JM (1992) The role of specific gravity for removal of hot melt adhesives in recyclable grades. TAPPI J 75(9):181–185

    CAS  Google Scholar 

  10. 10.

    Guest DA, Voss GP (1983) Improving the quality of recycled fibre. Paper Technol Ind 24:256–260, 268

    CAS  Google Scholar 

  11. 11.

    Espy HH, Geist GW (1992) Using neutral/alkaline-curing resins to produce wet-strength grades from recycled pulp. TAPPI J 75(7):192–196

    CAS  Google Scholar 

  12. 12.

    Marton R, Robie JD (1969) Characterization of mechanical pulps by a settling technique. TAPPI 52(12):2400–2406

    Google Scholar 

  13. 13.

    Höpner T, Jayme G, Ulrich JC (1955) Bestimmung des Wasserrückhaltevermögens (Quellwertes) von Zellstoffen. Papier 9:476–482

    Google Scholar 

  14. 14.

    Kitayama T, Okayama T, Oye R (1987) Changes of chemical pulp fibers during recycling. Sen'i Gakkaishi 43:486–494

    CAS  Article  Google Scholar 

  15. 15.

    Labosky P Jr, Martin RE (1969) Properties of paper obtained from ultrasonically and mechanically beaten pulps. Wood Sci 1:183–192

    Google Scholar 

  16. 16.

    Nanko H, Ohsawa J, Okagawa A (1989) How to see interfibre bonding in paper sheets. J Pulp Paper Sci 15:J17-J23

    CAS  Google Scholar 

  17. 17.

    Giertz HW (1958) The effects of beating on individual fibres. In: Bolam F (ed) Fundamentals of papermaking fibres. Technical Section, British Paper and Board Makers' Association, Kenley, pp 389–409

    Google Scholar 

  18. 18.

    Yamagishi Y, Oye R (1981) Influence of recycling on wood pulp fibers I. Jpn TAPPI J 35:787–797

    CAS  Article  Google Scholar 

  19. 19.

    Lindström T, Carlsson G (1982) The effect of carboxyl groups and their ionic form during drying on the hornification of cellulose fibres. Svensk Papperstidn 85:R146-R151

    Google Scholar 

  20. 20.

    Cao B, Tschirner U, Ramaswamy S (1998) Impact of pulp chemical composition on recycling. TAPPI J 81(12):119–127

    CAS  Google Scholar 

  21. 21.

    Deng Y, Abazeri M (1998) True flotation and physical entrainment: the mechanisms of fiber loss in flotation deinking. Nord Pulp Pap Res J 13(1):4–9, 15

    CAS  Article  Google Scholar 

Download references

Author information



Corresponding author

Correspondence to Takayoshi Matsumoto.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Tatsumi, D., Higashihara, T., Kawamura, S. et al. Ultrasonic treatment to improve the quality of recycled pulp fiber. J Wood Sci 46, 405–409 (2000).

Download citation

Key words

  • Ultrasonic frequencies
  • Deinking
  • Waste papers
  • Recycling
  • Reclaimed fibers