An antichlor is a substance used to decompose residual

hypochlorite In chemistry, hypochlorite is an anion with the chemical formula ClO−. It combines with a number of cations to form hypochlorite salts. Common examples include sodium hypochlorite (household bleach) and calcium hypochlorite (a component of ble ...

chlorine Chlorine is a chemical element with the Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate betwee ...

after chlorine-based

bleaching Bleach is the generic name for any chemical product that is used industrially or domestically to remove color (whitening) from a fabric or fiber or to clean or to remove stains in a process called bleaching. It often refers specifically, to ...

, in order to prevent ongoing reactions with, and therefore damage to, the material that has been bleached. Antichlors include

sodium bisulfite Sodium bisulfite (or sodium bisulphite, sodium hydrogen sulfite) is a chemical mixture with the approximate chemical formula NaHSO3. Sodium bisulfite in fact is not a real compound, but a mixture of salts that dissolve in water to give solutions ...

potassium bisulfite Potassium bisulfite (or potassium hydrogen sulfite) is a chemical mixture with the approximate chemical formula KHSO3. Potassium bisulfite in fact is not a real compound, but a mixture of salts that dissolve in water to give solutions composed of ...

sodium metabisulfite Sodium metabisulfite or sodium pyrosulfite (IUPAC spelling; Br. E. sodium metabisulphite or sodium pyrosulphite) is an inorganic compound of chemical formula Na2S2O5. The substance is sometimes referred to as disodium metabisulfite. It is used a ...

sodium thiosulfate Sodium thiosulfate (sodium thiosulphate) is an inorganic compound with the formula . Typically it is available as the white or colorless pentahydrate, . The solid is an efflorescent (loses water readily) crystalline substance that dissolves well i ...

, and

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscous than water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%� ...

.Hydrogen Peroxide is a Safe Alternative for Dechlorination
USP Technologies In the textile industry, the antichlor is usually added right before the end of the

bleach Bleach is the generic name for any chemical product that is used industrially or domestically to remove color (whitening) from a fabric or fiber or to clean or to remove stains in a process called bleaching. It often refers specifically, to ...

ing process. Antichlors are used mainly on

fiber Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate ...

textile Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, different fabric types, etc. At first, the word "textiles" only referred to woven fabrics. However, weaving is not the ...

s, and

paper pulp Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibers from wood, fiber crops, waste paper, or rags. Mixed with water and other chemical or plant-based additives, pulp is the major raw mate ...

. Rinsing with water should follow the antichlor treatment in order to flush out by-products of the procedure. For household use, rinsing both before and after use is recommended. Hydrogen peroxide is by itself a strong bleaching agent and should be used only in diluted form, such as a 3% solution in water. Hypochlorite plus peroxide releases

triplet oxygen Triplet oxygen, 3O2, refers to the ''S'' = 1 electronic ground state of molecular oxygen (dioxygen). It is the most stable and common allotrope of oxygen. Molecules of triplet oxygen contain two unpaired electrons, making triplet oxygen an unus ...

, which is itself a bleaching agent, but is short-lived in water solution. Reacting large amounts of peroxide can release enough oxygen to create a fire or explosion hazard. Antichlors are sometimes added to shampoos for treating hair after swimming in chlorinated water.

References

Antichlor {{Inorganic-compound-stub