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Water and detergent are used to wash textiles. Water wets the laundry and dissolves a large part of the laundry soiling. The exception is chemical cleaning, in which the textiles are cleaned with non-aqueous solvents.


Textiles can be washed with water at temperatures of up to 95 ° C, as it has a boiling point of 100 ° C. However, some properties of water have to be optimized for the washing process. For example, the surface tension of the water is reduced. But what is surface tension? The attempt to float a pin on water is known to exist. Then it looks like a skin has formed on the surface. However, this property prevents water from completely wetting textiles (or, in the case of cleaning agents, surfaces). Soap reduces surface tension. If you add a little washing-up liquid to the water, the pin sinks to the bottom.

Our drinking water is not chemically pure water (H2O), it contains, among other things, bound carbon, various minerals and trace elements. The hardness of the water is particularly important for the washing process. Water hardness is a measure of the content of calcium and magnesium salts (hardness components). The more of these salts the water contains, the harder the water is. The harder the water used, the greater the risk that the heating elements in the washing machine will become calcified. Hard water also interferes with the washing process. There are three hardness ranges:

  • soft = less than 8.4 ° dH (less than 1.5 millimoles calcium carbonate / liter)
  • medium = 8.4-14 ° dH (1.5-2.5 millimoles calcium carbonate / liter)
  • hard = more than 14 ° dH (more than 2.5 millimoles calcium carbonate / liter)

Information about how hard the water is in his community can be obtained from the waterworks.
Example: Stadtwerke Essen> Annual analysis of drinking water.


Instructions for washing wool with potash were written as early as 2500 BC. Soap was mentioned in ancient Egypt around 600 BC. A wide variety of detergent substances were used for washing: wood and plant ash, soda, urine and soap. In 1907 Persil came from the Henkel company and in 1909 Ozonit from Dr. Thompson out, both 'automatic' detergents. Since then, detergents have continued to evolve.

What are detergents made of?

Heavy duty detergents consist of the following ingredients:

  • Surfactants,
  • Softener,
  • Bleach,
  • Enzymes,
  • Optical brighteners,
  • Foam inhibitors,
  • Graying inhibitors,
  • Fragrances,
  • Thickening agents,
  • Preservatives (→ cleaning agents) and
  • partly dyes in liquid detergents.


Surfactants are washing-active substances. They reduce the surface tension of the water and thus ensure good wetting of the fabric. In addition, surfactants form the bridge between fat and water. Fat alone would not dissolve in water. Surfactants consist of a hydrophilic (water-loving) and a hydrophobic (water-repellent) part (Figures 5 and 6). These properties lock the dirt in micelles (Figure 3) and keep it floating in the water so that it can be washed out.

Figure 3: Surfactants combine to form a micelle

The hydrophilic part of a surfactant can have very different structures. If the hydrophilic part has a negative charge, one speaks of anionic surfactants, and a positive charge of cationic surfactants. Nonionic surfactants have no charge. Fatty alcohol sulfates are examples of anionic surfactants (Figure 4). Nonionic surfactants remove grease and oil contamination well. They also prevent synthetic fibers from turning gray.

Figure 4: Scheme of fatty alcohol sulfate (anionic surfactant)


Most surfactants are made from petroleum; the Fraunhofer Institute for Interfacial Engineering and Bioprocess Engineering IGB is working on a process to be able to produce biosurfactants from renewable raw materials. Biosurfactants also have the advantage that they are more easily biodegradable and less toxic (poisonous). They are produced by microorganisms that are grown in a nutrient medium made from sugar, oil, vitamins and mineral salts. In the next step, the biosurfactants are separated from the nutrient medium and the microorganisms. After it has been determined what they can be used for, for example in detergents or cosmetics, the properties are changed and improved (Environmentally friendly cleaning and washing, Fraunhofer Mediendienst 2.3.2012).


As described above, water can contain more or less calcium and magnesium ions. These ions bind surfactants and make them ineffective. For this reason, detergents contain water softeners that use different mechanisms to remove calcium and magnesium ions from the water or render them ineffective.
To soften the water z. B. Zeolites and Soap used. Zeolites are crystalline substances that soften water through ion exchange. Calcium and magnesium ions present in the water are exchanged for sodium ions.
Soap reacts with the calcium and magnesium ions contained in the water to form poorly soluble lime soap, which settles at the bottom and is then flushed outwards with the → free liquor. Also have a softening effect Polycarboxylatesthat are combined with zeolite and soda. Polycarboxylates have several effects: They prevent the crystal growth of poorly soluble alkaline earth metals, which also include magnesium (Mg) and calcium (Ca). This effect reduces polycarboxylates, the precipitation of crystals on the laundry and the heating elements of the → washing machine. In addition, polycarboxylates act as so-called complexing agents, which form stable complexes with metal ions such as Ca2 +, and polycarboxylates are effective graying inhibitors. Since polycarboxylates are poorly biodegradable, better alternatives are being sought.
Furthermore can Nitrilotriacetic acid (NTA) can be used for water softening. NTA is also a complexing agent. Although NTA is ecologically harmless, it is suspected of having a carcinogenic effect. That is why NTA is no longer in use in Germany. Phosphonates are also complexing agents but are mostly used as a stabilizer for sensitive ingredients such as bleach and enzymes. Here, by binding metal ions such as iron, copper and manganese ions, they increase the shelf life of bleaching agents.

On December 14, 2011, the EU Parliament passed a new EU regulation that bans the use of phosphates in detergents and cleaning agents. As of June 2013, the normal dosage of the detergent must not contain more than 0.5 grams of phosphorus. The deadline for detergents and dishwashing detergents is 1.1.2017; From this date the maximum permitted amount of phosphorus will be limited to 0.3 grams (EU restricts phosphate content in detergents).


Bleaching means removing unwanted stains (colored spots or yellowing). The structure of the dyes is destroyed during bleaching. As a result, the dyes lose their coloring properties and are more easily removed from the fibers. In the end, the dirt (hopefully) can no longer be seen. In the last few years, oxygen bleaching has replaced the more polluting "chlorine bleaching". In Germany, among other things, as bleach Sodium perborate or Sodium percarbonate used. At higher temperatures (from 60 ° C), bleaching-active oxygen is produced via hydrogen peroxide. Detergents are used for washing at temperatures below 60 ° C Tetraacetyl ethylenediamine (TAED) added as a bleach activator. Since nowadays washing is increasingly done at low temperatures, modern detergents contain relatively high TAED shares. Bleaching agents have the disadvantage of bleaching all colors, which is why they are not used in color and mild detergents.
In addition, bleaching agents have a microbicidal effect, i.e. they kill → microorganisms.


Enzymes are proteins that break down stains made of starch, protein or fat into their "building blocks" by dissolving their chemical compounds. The decomposition products are dissolved by surfactants and washed away with the → free liquor. Amylases split strength, Mannanase splits polysaccharides, which are made up of the simple sugar mannose, Lipases split fats and Proteases break down proteins (e.g. blood or milk). Cellulases if cellulose splits, rough cotton textiles become smooth again.
Since 2012, detergents have also been used Pectinases added. Pectinases break down pectins into smaller units so that they become water-soluble. In nature, pectins occur in all higher land plants. For example, pectin is found in fruits like apples, quince, and oranges, and vegetables like tomatoes and carrots. Pectin (E 440) is used in food as a gelling and thickening agent (→ food additives).
Enzymes, including those in detergents, are temperature-sensitive; they have the greatest effect between 40 ° C and 60 ° C. In addition, their effect depends on the pH of the washing liquor.

Optical brighteners

White textiles will yellow over time. For this reason, laundry used to be put in the sun for bleaching (lawn bleaching) or treated with laundry blue. The slight blue tint made yellowed laundry appear white again. In modern detergents, optical brighteners convert invisible UV light into visible blue light. The effect is the same as with laundry blue. Optical brighteners are particularly nice to see in the discotheque under black light, then white textiles shine particularly intensely.

Foam inhibitors

Perhaps you have already experienced in a washing machine with little load that a lot of foam has formed and escaped from the washing machine during the spin cycle. Foam inhibitors are added to detergents to prevent excessive foam production. These have a similar effect to soap in the bathtub, which causes the bath foam to collapse.

Graying inhibitors

They prevent dirt from settling on the fibers again after they have been removed and turning them gray.


You achieve that laundry smells fresh and pleasant after washing. However, fragrances can also trigger allergies, which is why in the EU 26 fragrances with a weight percentage of 0.01% or more must be declared on the packaging (Essential legal provisions, Bavarian State Office for the Environment).

Amyl cinnamalejasmine
Benzyl salicylateSweet, flowery
Butylphenyl Methylpropional (Lilial)Lily-like, lilac
CitronellolFlowery, rosy, citrus-like
GeraniolFlowery note
LinaloolFlowery and fresh, hint of citrus and spices

Thickening agent

Sodium sulphate is added to powder detergents to keep them flowing.

Detergent dosage

For heavy-duty detergents, at least the lowest specified dosage must be put in the washing machine, otherwise there will not be enough softener to get enough soft water for the washing process. Please ask your water company about the hardness of your water. With precise dosing, you save money and unnecessary detergent, which only pollutes the environment.

The different detergents

Heavy duty detergent

They contain all of the components described above. They are suitable for all washing temperatures (20 ° C to 95 ° C) and most textiles. But since they also contain optical brighteners and bleaching agents, they bleach colored textiles and the colors become paler. This effect is particularly undesirable with black clothing. Heavy-duty detergents are available as powder, granules, pearls, liquids, gels, tabs and liquid tabs.

Color detergent

The use of bleaching agents and optical brighteners is not used here. In addition, dye transfer inhibitors are added to prevent laundry from being discolored. However, dye transfer inhibitors also do not prevent the dyeing of new or heavily colored textiles. They should first be washed separately. Color detergents are available as powder, granules, pearls, liquids, gels, tabs and liquid tabs.

The following helps against detergent residues on clothing:

  • Not to overload the washing machine,
  • to dose the detergent precisely,
  • to have the laundry rinsed if there is foam residue.

Detergent for black

Detergents for black and dark clothing usually contain:

If you compare the ingredients with a liquid mild detergent for colored items, there are no differences in the active washing substances for some products. Other liquid color detergents have a higher proportion of anionic and / or nonionic surfactants (Comparison of the declared ingredients of some detergents for colored, black and sports and functional clothing).

The Stiftung Warentest tested detergents for black as early as 2001 and compared them with a liquid mild detergent for coloreds. The color detergent was just as gentle on the colors as the detergent for black and also washed just as well (Detergent for the dark: Too much black magic).

Mild detergent

They also contain no bleaching agents or optical brighteners and are adapted to low washing temperatures (up to 40 ° C). Some mild detergents do not contain cellulase. The addition of cellulase should be avoided with all cellulose fibers (→ viscose, modal), as these tissues are attacked by the enzymes. Detergents for mild detergents are available as powder and liquid.

Detergent for sports and functional textiles (microfibre, membrane and mixed fabrics)

A few years ago, mild detergents were recommended for washing → Gore-Tex jackets. Special detergents are now also available for these fabrics. The declared ingredients show nothing special compared to a conventional mild detergent. That's why I wrote to Henkel asking them to explain the difference to me, here is the answer:
"Our special detergent Perwoll for sports and functional textiles, in contrast to its classic variant as a mild detergent (Perwoll care for fine items), has additional ingredients that bind odorous substances such as those often found in sportswear (e.g. nitrogen, sulfur) or bind them in cavities This means that these substances no longer smell. "

Detergents for wool and silk

→ Wool and → silk are animal fibers that largely consist of protein. Wool detergents therefore do not contain any proteases (→ see enzymes) that would attack these natural fibers. As with mild detergents, bleaching agents and optical brighteners are not used here either. In contrast to other detergents, the washing liquor is pH-neutral. Wool detergents form a foam pad that is supposed to protect the fabric from excessive mechanical stress. Wool detergents are also suitable for → down. Wool detergents are available as powder and liquid.

Anti-pilling detergent / laundry additive

Anti-pilling detergents are designed to reduce pilling and smooth the surface of the fabric. Cellulase is listed as an ingredient in two products. In these cases, the products are suitable for vegetable fibers such as cotton and linen. If the products also contain proteases, animal fibers such as wool and silk can be damaged.Because animal fibers consist of protein-containing compounds (protein) that are split by this enzyme (→ see enzymes).

Curtain detergent

Curtains very often consist of → synthetic man-made fibers, which should only be washed at low temperatures. Since normal bleaches only work at higher temperatures, these detergents contain TAED, graying inhibitors and optical brighteners. The foam ensures gentle cleaning of the fabric. Curtain detergents are available as powder and liquid.

Disinfectant detergent

Laundry can be disinfected thermally, chemo-thermally (60 ° C washing temperature and disinfecting detergent) or chemically (40 ° C washing temperature and disinfecting detergent). For thermal disinfection, the Robert Koch Institute recommends an exposure time of 10 minutes at a washing temperature of 90 ° C, with a → liquor ratio of 1: 4 to 1: 5. The suitability of the detergent should be proven by an expert opinion. For chemo-thermal disinfection, disinfectant detergents are available that are suitable for different areas of activity and temperatures. The areas of action are marked with capital letters and designate the pathogens that can be killed or inactivated by the washing process. Disinfectant detergents are available for area A (bacteria, mycobacteria, fungi and their spores) and B (viruses). So that reliable disinfection can be carried out, not only the dosage of the detergent must be adhered to, but also the disinfection temperature, the exposure time and the → liquor ratio. Both the Robert Koch Institute (https://www.rki.de/) as well as the Association for Applied Hygiene e. V. (https://vah-online.de/) publish lists of suitable disinfectant detergents and the associated parameters. According to the Association for Applied Hygiene (VAH), laundry is successfully disinfected if the germ count is more than 7 log10Levels is reduced [1]. The reduction in the number of germs by a log10Level means that only 1/10 of the germ count is left. From the original 100 germs, only 10 remained afterwards. With a reduction of 7 log10-Stages would survive from an initial 10,000,000 germs 1 germ [2].

In private households it is usually not necessary to disinfect the laundry. Disinfectant detergents are also not necessarily effective in household washing machines. The Association for Applied Hygiene e. V. points out that in household washing machines there is sometimes a large difference between the temperature set and the temperature reached (see note on the subject of the 60-degree program for household washing machines). To be sure, the disinfection result must be checked with biological indicators.

Modular system

With the modular systems, the components are available individually and can be dosed individually. In this way, the proportion of softener can be increased without increasing the dosage of the active washing substances. Usually there is a basic detergent with active washing substances (surfactants), water softeners and bleaching agents. In addition, enzymes and fragrances are obtained separately. This is a very environmentally friendly form of washing, but the modular systems are not available everywhere and the dosage is more laborious than with a heavy-duty detergent.

Detergents for different degrees of hardness

The "campaign for intelligent washing" is breaking new ground. She has released three different detergents for the three degrees of water hardness (soft, medium, hard). According to the manufacturer, up to 41% surfactants can be saved compared to a conventional washing powder https://www.waschkampagne.de/.

In addition to these detergents, a number of others have come onto the market:

  • Leather detergents have a moisturizing effect → leather care,
  • Detergents for allergy sufferers,
  • Detergent for jeans,
  • Detergents for lingerie,
  • Down detergent.

It is not always clear what the advantage of one of these special detergents should be.

The topics

Interesting links

Law on the environmental compatibility of detergents and cleaning agents. Date of issue: 04/29/2007
Waschen Forum (2017): Contact allergies and irritations: Do detergents and cleaning agents play a role? Accessed on June 21, 2018
Regulation (EC) No. 648/2004 of the European Parliament and of the Council of March 31, 2004 on detergents (OJ EU No. L 104 p. 1), amended by Regulation (EC) No. 907/2006 of June 20 2006 (OJ EU No. L 168 p. 5)
INCI (International Nomenclature of Cosmetic Ingredients) - database on Haut.de
Federal Institute for Risk Assessment (BfR) (2014): New liquid detergents can cause poisoning accidents in children. Accessed May 14, 2020


[1] Association for applied hygiene (VAH) (Ed.): Germ contamination of washing machines and laundry. Accessed on April 12th, 2021
[2] Lower Saxony State Health Office (2020) (Ed.): Review of the disinfection performance of hygiene-relevant devices in geriatric care facilities. Accessed on April 12th, 2021
KATALYSE Institut e. V .: phosphonates. Accessed on April 20, 2017
Bavarian State Office for the Environment (2017): UmweltWissen - Praxis. Detergents and cleaning agents. Accessed on June 21, 2018
Wikipedia entry: Nitrilotriacetic acid. Accessed on February 9, 2017 at 3:40 p.m.
Wikipedia entry: Pectins. Accessed on April 20, 2017 at 1:15 p.m.
List of the disinfectants and methods tested and recognized by the Robert Koch Institute. Accessed on 20.086.2019
Suitability of VAH-listed chemothermal laundry processes when used in household washing machines, Communication No. 7/2010 of the Disinfectant Commission
Detergent for the dark: Too much black magic, Stiftung Warentest 04/2001, last accessed on October 23, 2011
Benzyl salicylate, The Good Scents Company, last visited on November 2nd, 2011
Wikipedia entry: water hardness. Accessed on January 17, 2014
Wikipedia entry: Eugenol. Accessed on November 2nd, 2011
Wikipedia entry: Geraniol. Accessed on November 3, 2011
Fragrance Lexicon: Linalool. Accessed on April 20, 2017
BASF SE: Citronellol. Last visited on April 20, 2017
Transparency genetic engineering, the transGEN database: Mannanase. Accessed on April 20, 2017
Bavarian State Office for the Environment: Essential legal provisions. Accessed on August 3rd, 2017
EurActiv.de: New regulation passed in EU parliament, EU abolishes phosphates in budget funds, 14.12.2011
EUROPEAN COMMISSION (2015): REPORT FROM THE COMMISSION TO THE EUROPEAN PARLIAMENT AND THE COUNCIL pursuant to Article 16 of Regulation (EC) No. 648/2004 of the European Parliament and of the Council of 31 March 2004 on detergents relating to the use of phosphates in the Consumers use certain machine dishwashing detergents. Accessed on June 21, 2018
Fraunhofer Mediendienst (2012): Environmentally friendly cleaning and washing. Accessed February 8, 2017
Prof. Blum's educational server for chemistry (2010): Bleichmittel. Accessed February 8, 2017
Monika Pohl, Jean Pütz: Washing clothes with a white vest, hobby tip No. 305
Henkel: Lovables Intensive Anti-Pilling Repair. Accessed on August 20, 2019
Henkel: Perwoll Care & Repair Advance. Accessed on August 20, 2019
Lexicon from Seifenshop.de, accessed on November 2, 2011 (link no longer available)
Günter Wagner: detergents. Chemistry, environment, sustainability. 2017
Jean Pütz, Christine Niklas: Creams and gentle soaps, do-it-yourself cosmetics, natural and healthy, 1987
Prof. Dr. Volkmar Dietrich, Natural Sciences, From Washing. 2000
TEST color detergent: jacket and pants, ÖKO-TEST magazine 8/2009
Persil laundry care compass, 06/2008

Detailed references

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