repellent

(redirected from repellence)
Also found in: Dictionary, Thesaurus, Medical, Legal.

repellent

a substance with which fabrics are treated to increase their resistance to water

Repellent

 

a substance that repels arthropods (insects and ticks), mammals, and birds. Repellents are used mainly to protect man and animals from attacks by bloodsucking insects, to prevent such infectious diseases as encephalitides and leishmaniases, and to protect clothing and furniture from arthropods.

Repellents of plant and animal origin, including herbs and vegetable oils, have been used since ancient times. Today, most repellents are long-acting chemical preparations that are mainly synthetic. These include ethers and esters, alcohols, aldehydes, amides, and essential oils.

Repellents are classified according to the type of action they exert on arthropods. Olfactory repellents, or fumigants, are volatile substances that act at a distance and affect the nerve endings of insects’ olfactory organs. They include dimethyl phthal-ate, DETA, and kiuzol. Bite-preventing or contact repellents, including anabasine, hecamide, and Indalone, act on arthropods that come in direct contact with the treated surface. Masking, or deodorizing, repellents, such as lemon and clove oils, destroy or neutralize odors that attract arthropods. In areas with a great many bloodsucking arthropods, it is only with the use of repellents that such undertakings as geological investigations and the laying of conduits can take place.

Repellents are applied to exposed parts of the body or to clothing, protective netting, and tents. Repellents applied to the skin are in lotion or other liquid form; they may also be unguents or creams or in aerosol form. The duration of the protective effect depends on such factors as weather and the properties of the repellent itself.

When repellents come in contact with the mucosa of the eyes, nose, or mouth they produce irritation. If this takes place, especially among persons with allergies, the repellent must be washed off and its use discontinued. In treating fabrics, the material is wetted or soaked in a liquid repellent; it may also be treated with solid repellents—wax crayons and bars, paraffin, or stearin—or with aerosol bombs. Fabrics given a single treatment retain their repellent effect for several days, several weeks, or the entire period during which the arthropods are active.

Outside the USSR, repellents are also used to treat forest stands and fruit crops to protect them from deer, roe deer, hares, murine rodents, and birds. Effective repellents for protecting plants from harmful insects and ticks have not yet been found but are being intensively developed.

REFERENCES

Gladkikh, S. G. Sredstva, otpugivaiushchie krovososushchikh nasekomykh i kleshchei. Moscow, 1964. (Contains bibliography.)
Nepoklonov, A. A. Khimicheskie sredstva zashchity zhivotnykh. Moscow, 1971.
Dremova, V. P. “Naibolee effektivnye sovremennye repellenty i taktika ikh primeneniia.” In Prirodnaia ochagovost’ boleznei i voprosy parazitologii zhivotnykh: Trudy 7 Vsesoiuznoi konferentsii po prirodnoi ocha-govosti boleznei i obshchim voprosam parazitologii zhivotnykh, fase. 6, part 2. Tashkent, 1972.

T. S. POTSHEBA

References in periodicals archive ?
2009; Correa, 2011) showing the potential of use of clove essential oil, whether by contact, repellence or fumigation, the authors observed that clove essential oils can become an alternative to the conventional insecticides for the mortality of populations of A.
Mortality and repellence of Eupalamides cyparissias (Lepidoptera: Castniidae), pest of oil palm Elaeis guineensis, by effect of ten botanical extracts
insects overcame the repellence of the floral chemicals and that
2%) as a processing aid for other polymers to improve flow, low-temperature flexibility, and water repellence.
The type and amount of material used to impart water repellence may affect future paintability of the treated surface.
In an example of practical biomimetics he described the 'astonishing' properties of microstructures, including dirt repellence, total reflection, and self-cleaning optics.
Aimed at SUV buyers with an active lifestyle, the fabric retains the softness and wear resistance of standard automotive seat fabrics, but with much higher levels of water repellence and stain resistance.
Developed to combat the increased weight and lack of control players experience when the ball is played in damp conditions, Hydroguard technology features a patented application process on premium woven cloth, which increases its repellence to water.
With the Tyvek cover, they noted moisture repellence as a particularly good feature.
salicaria through visual or olfactory interference or repellence.
The company, which specialises in rubber flooring solutions, says a few characteristics of its nora floorcoverings include environmental compatibility and extra-ordinary wear resistance, repellence of dirt and fire protection properties.
Moreover, says the company, the new product allows hydrophobic ingredients to continually migrate from the epoxy, through layers of pollution to the surface of an insulating part, reestablishing and maintaining water repellence over time to extend service life significantly.