Paint remover
Paint remover (also paint stripper ) are chemical compounds that help old paints and varnishes (z. B. on wood) can be removed. The process is called "stripping" or "leaching" (see also pickling ).
A general distinction is made between leaching and dissolving paint strippers.
They can be in gel form for easier application. The paint stripper has to take effect for a certain period of time (about an hour for quick paint strippers) before the dissolved paint can be removed with a spatula and water.
Components of paint remover
The areas of application of paint strippers are varied. Therefore the individual components in the paint remover are varied. A distinction is not only made between alkaline and solvent paint strippers. The choice of different thickeners and wetting agents also changes the consistency and effectiveness of the paint stripper. Thickeners ensure that the paint stripper becomes firmer overall. This allows it to be used on vertical surfaces without the product sagging on the floor or other surfaces. Wetting agents are added to reduce the surface tension of the solvent . This allows the paint stripper to pass through several layers of paint or varnish.
Ingredients of alkaline paint strippers
| alkaline solutions | Thickener | Wetting agents |
|---|---|---|
|
Alkaline substances are only added to alkaline paint strippers. They break down the oils and varnishes so that they can be scraped off the surfaces.
Ingredients of solvent paint strippers
| flammable | hardly flammable | Thickener | Wetting agents |
|---|---|---|---|
|
The substances designated as hardly combustible are added in order to reduce the overall combustibility of the paint stripper, as some components have very low flash points and are easily combustible. Older, solvent paint strippers are often based on the highly hazardous organic solvent dichloromethane (DCM). This is therefore being replaced in the present.
Despite this classification, there are also some products that contain both alkaline and solvent substances at the same time.
Problems with using paint strippers
The use of alkaline paint strippers is viewed critically by experts. The surface must be completely neutralized , otherwise in the presence of water (especially when used outdoors) the stripping agent will start working again, which will damage the new coat and will have to be renewed. For example, application on windows is rejected. In addition, some woods, such as cherry or oak , can be permanently discolored by the lye.
The components of the paint remover often have a harmful effect on humans and the environment, in particular the chlorinated hydrocarbons they contain . They are almost exclusively carcinogenic and have a strong influence on the greenhouse effect . Examples are dichloromethane or ethylene chloride. Work with paint strippers should always be carried out in the fresh air, at least in well-ventilated rooms. Another important aspect is the disposal of paint strippers. These should never be disposed of with household waste, even if they are labeled as environmentally friendly. They should always be disposed of as hazardous waste.
Individual evidence
- ↑ a b c Bernhard Schulz: Paint remover and the removal of old paint. In: Colorant Science . No. 7, 1953, pp. 117-119, doi: 10.1007 / 978-3-322-98438-8_12 .
- ↑ Erich Kosinski: This is how the painter works - working techniques of the painting trade. Berlin 1965, p. 108.
- ^ Wolf Schmidt: Repair of historical wooden windows. In: Monument preservation information . Bavarian State Office for Monument Preservation, Munich 2004, p. 36.
- ↑ Tobias Huckfeldt, Hans-Joachim Wenk: wooden windows - construction, damage, renovation, maintenance. Cologne 2009, p. 279 and 280.
