impregnation

from Wikipedia, the free encyclopedia

Impregnation ( impregnation ) (derived from the late Latin verb impraegnare for pregnant, soaking, filling with a substance) is an impregnating treatment of solid, porous materials, such as B. textiles , paper , wood , concrete and. Ä, with dissolved, emulsified or dispersed substances, the impregnating agents. After the solvent or dispersion medium has evaporated or dried, the applied substances give the treated materials modified properties. This allows new areas of application to be opened up.

Order options

There are different methods or aggregates to apply impregnation agents, e.g. B .:

  • Padding
  • Diving
  • Spray
  • Pressure impregnation
  • Patting (kiss-roll)

application areas

Textile finishing

In the field of textile finishing the term impregnation is sometimes synonymous with the waterproofing uses of textiles, said in a water-pressure-resistant and water-repellent equipment (English: repellent durable water ) is divided, on the other hand only for a waterproof equipment. It also plays a role that under impregnation z. T. the state achieved is understood by the impregnation. Depending on the requirements for washing, cleaning and weather resistance , paraffin and wax emulsions , but also film-forming silicones and fluorocarbons , which provide good permanent protection, are used as impregnation agents . Impregnation also introduces substances into textile materials that make them crease- resistant, protected from eating (moth and beetle protection), rot-proof , flame-proof , but also hydrophilic . Some of the fluorocarbon resins (PFC) used as impregnating agents can accumulate in the human organism and impair human fertility. However, impregnant suppliers do not have to disclose whether they use fluorocarbons. Stiftung Warentest did not find any substances harmful to health in a test of impregnating agents, but referred to the fact that, in view of the more than 800 corresponding active ingredients, not everyone can be identified individually.

Nonwoven production

One possibility for the production of nonwovens is a chemical consolidation of the fiber nonwovens by applying binder dispersions, emulsions or solutions by impregnation into the fiber nonwoven. This can be done as an immersion bath impregnation or as a foam impregnation. The excess binding agent is squeezed off using a padder. Subsequent drying and condensation creates an adhesive bond between the binder and the fibers.

Construction

In the construction industry, various purposes are pursued when soaking building materials by various means:

  • reducing water intake
  • the protection of the surface against dirt
  • the strengthening of the layers close to the surface against weathering , wear and tear or in preparation for further coatings
  • the reduction of the pore volume and the absorbency to control the diffusion resistance or to prepare for further coatings
  • the glaze-like coloring of the material

As an alternative to the diffusion-open impregnation that penetrates the material, sealing or coating the surface, which can also be part of a surface protection system , is often an option .

Wood can be treated by dipping, spraying and pressure impregnation , see also wood protection processes and impregnations .

The impregnation of plaster , stone and concrete surfaces against the ingress of moisture is also called hydrophobization . A large number of products are used to protect natural stone surfaces from soiling and discoloration (see, inter alia, Testalin ).

Paper industry

In the decor paper industry, during impregnation (also called resin coating), a wide variety of papers are soaked in a resin bath and then dried. The impregnated papers can then be pressed onto various carrier boards (chipboard, MDF board, etc.) under high pressure and high temperature.

Another application of impregnation can be found, for example, in the manufacture of painter's adhesive tape. The paper is impregnated with a plastic polymer to make it more wet-strength and to increase the breaking strength.

histology

In histology , fixed and dehydrated tissue samples are soaked with xylene (clarifying agent, intermediate). During the impregnation step (penetration to saturation), the xylene is displaced by hot, liquid paraffin. The effect of negative pressure (vacuum) facilitates the exchange of liquids, the increased temperature (at 60 ° C) facilitates the evaporation of the clarifying agent and reduces the viscosity . The impregnation with plastics is carried out with a monomeric, liquid solution, which is then stimulated to polymerize and thereby solidify.

Environmental issues

Perfluorinated surfactants from impregnating agents (especially for (re) waterproofing breathable textiles), which are also used in households, get into the environment via household sewage and accumulate there because they are not biodegradable. Wood, in this case waste wood, construction wood and demolition wood that has been treated, should not be disposed of in the conventional way or burned.

literature

  • Victor von Röll : Encyclopedia of the Railway System . 2nd Edition. Urban & Schwarzenberg, Berlin / Vienna 1923 ( zeno.org [accessed on May 22, 2019] Lexicon entry “Tränkungsverfahren”).

Individual evidence

  1. ^ Lexicon technology and exact natural sciences. Volume 5, Fischer Taschenbuch Verlag, Frankfurt am Main 1972, ISBN 3-436-01562-8 , p. 1511.
  2. ↑ Meyer's large pocket dictionary in 24 volumes. Volume 10, Bibliographisches Institut & FA Brockhaus, Mannheim 1992, ISBN 3-411-11104-6 , p. 140.
  3. ^ Paul-August Koch , Günther Satlow: Large Textile Lexicon: Specialized lexicon for the entire textile industry. Volume A-K. Deutsche Verlags-Anstalt, Stuttgart 1965, p. 616.
  4. ^ Hugo Glafey (Hrsg.): Textile Lexicon - concise dictionary of the entire textile industry. Deutsche Verlags-Anstalt, Stuttgart / Berlin 1937, p. 379.
  5. ^ Alois Kießling, Max Matthes: Textile - specialist dictionary . Fachverlag Schiele & Schön, Berlin 1993, ISBN 3-7949-0546-6 , p. 186.
  6. ↑ Fabia Denninger, Elke Giese: Textile and Model Lexicon . Volume A-K. 8th, completely revised and expanded edition. Deutscher Fachverlag, Frankfurt am Main 2006, ISBN 3-87150-848-9 , p. 328.
  7. ↑ See the article in the English Wikipedia Durable water repellent
  8. ↑ Ursula Völker, Katrin Brückner: From fiber to fabric - Textile materials and goods. Publishing house Dr. Felix Büchner, Hamburg 2007, ISBN 978-3-582-05112-7 , p. 207.
  9. ↑ Fabia Denninger, Elke Giese: Textile and Model Lexicon . Volume A-K. 8th, completely revised and expanded edition. Deutscher Fachverlag, Frankfurt am Main 2006, ISBN 3-87150-848-9 , p. 328.
  10. ^ Paul-August Koch, Günther Satlow: Large Textile Lexicon: Specialized lexicon for the entire textile industry . Volume A-K. Deutsche Verlags-Anstalt, Stuttgart 1965, p. 617.
  11. ↑ Fabia Denninger, Elke Giese: Textile and Model Lexicon . Volume A-K. 8th, completely revised and expanded edition. Deutscher Fachverlag, Frankfurt am Main 2006, ISBN 3-87150-848-9 , p. 328.
  12. ^ Alois Kießling, Max Matthes: Textile - specialist dictionary . Fachverlag Schiele & Schön, Berlin 1993, ISBN 3-7949-0546-6 , p. 186.
  13. ↑ Impregnation agent for textiles and leather: Every second is good , test.de , August 27, 2015, accessed on September 3, 2015.
  14. ^ Peter Böttcher, Günter Schröder, Wolfgang Möschler: Vliesstoffe . Fachbuchverlag, Leipzig 1976, p. 76.
  15. ^ Radko Krčma: Handbook of textile composites (non wovens). Deutscher Fachverlag, Frankfurt am Main 1970, p. 58.
  16. ^ Federal Environment Agency , accessed on November 11, 2011.
  17. ↑ Surfactants, nanoparticles and drug residues in the groundwater. Retrieved November 11, 2011.

See also