bleach

1. To remove the color from, as by means of chemical agents or sunlight.
2. To make white or colorless.

To become white or colorless.

1. A chemical agent used for bleaching.
2. 1. The act of bleaching.
   2. The degree of bleaching obtained.

[Middle English blechen, from Old English blǣcan.]

Background

Bleach is a chemical compound derived from natural sources used to whiten fabrics. Bleach works by the process of oxidation, or the alteration of a compound by the introduction of oxygen molecules. A stain is essentially a chemical compound, and the addition of bleach breaks down the molecules into smaller elements so that it separates from the fabric. Detergent and the agitation of the washing machine speed up the cleaning process. The disinfecting properties of bleach work in the same manner—germs are broken down and rendered harmless by the introduction of oxygen. In industry, different forms of bleach are used to whiten materials such as paper and wood, though most bleach is used to launder textiles.

History

Humans have been whitening fabrics for centuries; ancient Egyptians, Greeks, and Romans bleached materials. As early as 300 B.C., soda ash, prepared from burned seaweed, was used to clean and whiten cloth. During the Middle Ages, the Dutch perfected the bleaching of fabrics in a process called crofting, whereby fabrics were spread out in large fields for maximum sunlight exposure. Textile mills as far away as Scotland shipped their material to the Netherlands for this bleaching. The practice quickly spread throughout Europe, and bleaching fields were documented in Great Britain as early as 1322. In 1728 a bleaching company using Dutch methods went into business in Galloway, Scotland. In this process, the fabrics were soaked in a lye solution for several days, then "bucked," or washed clean. The fabrics were then spread out on the grass for weeks at a time. This process was repeated five or six times until the desired whiteness was achieved. Next, the fabric was treated with sour milk or buttermilk, and again bucked and crofted. This method was lengthy and tedious, and it monopolized large tracts of land that could have been used for farming.

Late in the 18th century, scientists discovered a chemical that had the same effect as crofting, but yielded much quicker results. In 1774, Swedish chemist Karl Wilhelm Scheele discovered the chemical element chlorine, a highly irritating, green-yellowish gaseous halogen. In 1785, the French scientist Claude Berthollet found that chlorine was an excellent whitening agent in fabrics. Some mill operators attempted to expose their fabrics to chlorine gas, but the process was so cumbersome and the fumes so strong that these attempts were soon abandoned.

Near Paris, in the town of Javel, Berthollet began a small facility for the manufacture of a new product called "Eau de Javelle." The bleaching powder consisted of potash (soda ash) which had absorbed chlorine gas. In 1799, another bleaching powder was invented by Scottish chemist Charles Tennant. In the early years of the Industrial Revolution, his patented lime powder was widely used to whiten a variety of fabrics and paper products. To make the bleaching powder, slaked lime (lime treated with water) was spread thinly over the concrete or lead floor of a large room. Chlorine gas was pumped into the room to be absorbed by the lime. Though an effective whitener, the powder was chemically unstable. It was commonly used until around World War I, when liquid chlorine and sodium hypochlorite solutions—the forerunners of modern household bleach—were introduced. About this time, researchers found that injecting salt water with electrical current broke down the salt (sodium chloride) molecules and produced a compound called sodium hypochlorite. This discovery enabled the mass production of sodium hypochlorite, or chlorine, bleach.

Types of Bleach

Today, bleach is found in nearly every household. It whitens fabrics and removes stains by a chemical reaction that breaks down the undesired color into smaller particles that can be easily removed by washing. The two types of household bleach are chlorine bleach and peroxide bleach. Peroxide bleach was introduced in the 1950s. Though it helps to remove stains, especially in higher wash temperatures, it will not bleach most colored materials and does not weaken fabrics, as does sodium hypochlorite bleach. Peroxide bleach does not disinfect and is commonly added to laundry detergents which are advertised as color-safe. It also has a longer shelf life than chlorine bleach. Peroxide bleach is more commonly used in Europe, where washing machines are manufactured with inner heating coils that can raise the water temperature to the boiling point.

The more common form of household bleach in the U.S. is chlorine bleach. It is most effective in removing stains and disinfecting fabrics. Chlorine bleach is cheap to manufacture and effective in both warm and hot wash temperatures. However, it has strong chemical properties which can weaken textile fibers.

The disinfecting properties of chlorine bleach can also be useful outside the laundry. Chlorine bleach disinfects drinking water where groundwater contamination has occurred, as it is a powerful germicide. It was first used to sanitize drinking water in New York City's Croton Reservoir in 1895, and is approved by the government for sanitizing equipment in the food industry. In recent years, bleach has been promoted by community health activists as a low-cost method of disinfecting the needles of intravenous drug users.

Raw Materials

The raw materials for making household bleach are chlorine, caustic soda, and water. The chlorine and caustic soda are produced by putting direct current electricity through a sodium chloride salt solution in a process called electrolysis. Sodium chloride, common table salt, comes from either mines or underground wells. The salt is dissolved in hot water to form a salt solution, which is then treated for impurities before it is reacted in the electrolytic cell.

The Manufacturing
Process

The manufacture of sodium hypochlorite bleach requires several steps. All the steps can be carried out at one large manufacturing facility, or the chlorine and caustic soda can be shipped from different plants to the reactor site. Both chlorine and caustic soda are hazardous chemicals and are transported according to strict regulations.

Preparing the components

• Caustic soda is usually produced and shipped as a concentrated 50% solution. At its destination, this concentrated solution is diluted with water to form a new 25% solution.
• Heat is created when the water dilutes the strong caustic soda solution. The diluted caustic soda is cooled before it is reacted.

The chemical reaction

• Chlorine and the caustic soda solution are reacted to form sodium hypochlorite bleach. This reaction can take place in a batch of about 14,000 gallons or in a continuous reactor. To create sodium hypochlorite, liquid or gaseous chlorine is circulated through the caustic soda solution. The reaction of chlorine and caustic soda is essentially instantaneous.

Cooling and purifying

• The bleach solution is then cooled to help prevent decomposition.
• Often this cooled bleach is settled or filtered to remove impurities that can discolor the bleach or catalyze its decomposition.

Shipping

• The finished sodium hypochlorite bleach is shipped to a bottling plant or bottled on-site. Household-strength bleach is typically 5.25% sodium hypochlorite in an aqueous solution.

Quality Control

In the bleach manufacturing facility, the final sodium hypochlorite solution is put through a series of filters to extract any left-over impurities. It is also tested to make certain that it contains exactly 5.25% sodium hypochlorite. Safety is a primary concern at manufacturing plants because of the presence of volatile chlorine gas. When the chlorine is manufactured outside the reactor facility, it travels in liquid form in specially designed railroad tank cars with double walls that will not rupture in the event of a derailment. On arrival at the plant, the liquid chlorine is pumped from the tank cars into holding vat.. As a safety measure, the tank cars have shutoff valves that work in conjunction with a chlorine detection system. In the event of a chlorine leak, the detection system triggers a device on the tank that automatically stops the transmission of the liquid in 30 seconds.

Inside the facility, chlorine vats are housed in an enclosed area called a car barn. This enclosed room is equipped with air "scrubbers" to eliminate any escaped chlorine gas, which is harmful to humans and the environment. The vacuum-like scrubber inhales any chlorine gas from the enclosed area and injects it with caustic soda. This turns it into bleach, which is incorporated into the manufacturing process. Despite these precautions, safety and fire drills are scheduled regularly for plant personnel.

Special Considerations in
Packaging

Household sodium hypochlorite bleach was introduced to Americans in 1909 and sold in steel containers, then in glass bottles. In the early 1960s, the introduction of the plastic jug brought a cheaper, lighter, and nonbreakable packaging alternative. It reduced transportation costs and protected the safety of workers involved in its shipping and handling. Additionally, the thick plastic did not permit ultraviolet light to reach the bleach, which improved its chemical stability and effectiveness. In recent years, how-ever, plastic containers have become an environmental concern because of the time it takes the material to decompose in a landfill. Many companies that depend on plastic packaging, including bleach manufacturers, have begun to reduce the amount of plastic in their packaging or to use recycled plastics. In the early 1990s, Clorox introduced post-consumer resins (PCR) in its packaging. The newer bottles are a blend of virgin high-density polyethylene (HDPE) and 25% recycled plastic, primarily from clear milk jug-type bottles.

Consumer Safety

The bleach manufacturing industry came under fire during the 1970s when the public became concerned about the effects of household chemicals on personal health. Dioxin, a carcinogenic byproduct of chemical manufacturing, is often found in industrial products used to bleach paper and wood. In its final bottled form, common sodium hypochlorite bleach does not contain dioxins because chlorine must be in a gaseous state for dioxins to exist. However, chlorine gas can form when bleach comes into contact with acid, an ingredient in some toilet-bowl cleaners, and the labels on household bleach contain specific warnings against such combination.

In addition to the danger of dioxins, consumers have also been concerned about the toxicity of chlorine in sodium hypochlorite bleach. However, the laundry process deactivates the potentially toxic chlorine and causes the formation of salt water. After the rinse water enters the water system through the household drain, municipal water filtration plants remove the remaining traces of chlorine.

Where To Learn More

Periodicals

Ainsworth, Susan. "Resurgence in Demand Reviving Market for Sodium Chlorite." Chemical & Engineering News, March 22, 1993, pp. 11-12.

Grime, Keith and Allen Clauss. "Laundry Bleaches and Activators." Chemistry and Industry, October 15, 1990, pp. 647-49.

[Article by: Carol Brennan]

The manufacturing section of this entry was written with the help of Clorox Company.

verb

To lose normal coloration; turn pale: blanch, etiolate, pale, wan. See colors/colorless.

Definition: whiten
Antonyms: blacken, darken, yellow

For more information on bleach, visit Britannica.com.

This article is about the chemical whitener. For the media franchise, see Bleach (manga). For other uses, see Bleach (disambiguation).

Commercial sodium hypochlorite bleach

A bleach is a chemical that removes colors or whitens, often via oxidation. Common chemical bleaches include household "chlorine bleach", a solution of approximately 3–6% sodium hypochlorite (NaClO), and "oxygen bleach", which contains hydrogen peroxide or a peroxide-releasing compound such as sodium perborate, sodium percarbonate, sodium persulfate, sodium perphosphate, or urea peroxide together with catalysts and activators, e.g. tetraacetylethylenediamine and/or sodium nonanoyloxybenzenesulfonate. To bleach something is to apply bleach, sometimes as a preliminary step in the process of dyeing. Bleaching powder is calcium hypochlorite.

Many bleaches have strong bactericidal properties, and are used for disinfecting and sterilizing. Most bleaches are hazardous if ingested or inhaled, and should be used with care.

Contents 1 Other types of bleaches 2 Human and environmental safety 2.1 Human safety 2.2 Environmental impact 2.3 Chemical interactions 3 Chemistry 4 Mechanism of bleach action 5 Antimicrobial efficacy 6 See also 7 References 8 Further reading 9 External links

Other types of bleaches

Chlorine dioxide is used for the bleaching of wood pulp, fats and oils, cellulose, flour, textiles, beeswax, skin, and in a number of other industries.

In the food industry, some organic peroxides (benzoyl peroxide, etc.) and other agents (e.g. bromates) are used as flour bleaching and maturing agents.

Peracetic acid, ozone^[1] and hydrogen peroxide and oxygen are used in bleaching sequences in the pulp industry to produce Totally Chlorine Free (TCF) paper.

Not all bleaches have an oxidizing nature. Sodium dithionite is used as a powerful reducing agent in some bleaching formulas. It is commonly used to bleach wood pulp used to make newsprint.

Human and environmental safety

Studies of human safety and environmental effects associated with household use of sodium hypochlorite bleach have been extensively documented. A review of these studies ^[2] by the International Association for Soaps, Detergents and Maintenance Products (AISE) in 2007 confirmed that:

Human safety

• Neither carcinogenesis, mutagenesis, nor teratogenesis are indicated
• There may be minor, temporary effects such as localized skin and eye irritant (localized; potentially increasing with concentration, but this is unlikely to be significant at levels encountered in the household). There are no chronic effects, and while accidental acute effects can be painful, they are mostly reversible
• Hypochlorite imparts no systemic effects; it does not cause sensitization
• Excessive exposure to hair may cause thinning or temporary balding.

Environmental impact

• No emissions of sodium hypochlorite from normal household or institutional use find their way directly to the environment. Sodium hypochlorite degrades quickly, primarily to sodium chloride, during use or in sewage systems. It also decomposes in soil, primarily to salt. Typical use was found to be not harmful to sewage treatment or septic tanks
• Sodium hypochlorite is toxic when undiluted (5% concentration as sold), but is rapidly diluted or decomposed to harmless levels in soil or sewage systems.
• While highly toxic to fish and invertebrates in confined spaces, fish will swim away from the source if possible. In addition, sodium hypochlorite readily disperses and degrades mostly to salt in surface waters, limiting impact
• Very low levels absorbable organic halides (AOX) can be found during reaction of sodium hypochlorite and soils, including carbon tetrachloride, trihalomethanes (THM, such as chloroform), and trihaloacetic acid (THAA). Most AOX go into the sewer with wash water; amounts emitted to air well below safe limits. Most AOX degrades in sewage treatment like starting soil; wastewater genotoxicity not increased. Remnants are not harmful at levels detected (acute and chronic); no persistent or lipophilic chlorinated compounds were detected. Limited amounts of AOX have been detectable on fabrics below significant effect levels
• Bleach is not a source of dioxin, which only forms below pH 5 (at least 100 times lower than household applications). The risk of generating dioxin from use of household bleach is non-existent
• Chlorate ion can form during decomposition of sodium hypochlorite, but is readily decomposed during waste treatment
• Perchlorate can also form through decomposition; it is estimated that less than 5 ppb could be released in the wash, and less than 1 ppb could be found after dilution in waste treatment and septic systems. Most prevalent sources of perchlorate contamination in environment found to be blasting agents, military munitions, and fireworks. Massachusetts EPA concluded that normal household discharge of bleaches into municipal sewerage or conventional septic systems should not be an environmental issue

In 2008, the Scientific Committee on Health and Environmental Risks (SCHER) for the European Commission concluded that the Risk Assessment Report (RAR) was of good quality, and agreed with its conclusions. No further study on human health is indicated. ^[3]

Chemical interactions

Hypochlorite and chlorine are in equilibrium in water; the position of the equilibrium is pH dependent and low pH (acidic) favors chlorine,^[4]

Cl₂ + H₂O H⁺ + Cl^- + HClO

Chlorine is a respiratory irritant that attacks mucous membranes and burns the skin. As little as 3.53 ppm can be detected as an odor, and 1000 ppm is likely to be fatal after a few deep breaths. Exposure to chlorine has been limited to 0.5 ppm (8-hour time-weighted average—38 hour week) by OSHA in the U.S.^[5]

Sodium hypochlorite and ammonia react to form a number of products, depending on the temperature, concentration, and how they are mixed. ^[6]. The main reaction is chlorination of ammonia, first giving chloramine (NH₂Cl), then dichloramine (NHCl₂) and finally nitrogen trichloride (NCl₃). These materials are very irritating to eyes and lungs and are toxic above certain concentrations. Lastly there is bleach containing sodium perchlorate.

NH₃ + NaOCl --> NaOH + NH₂Cl

NH₂Cl + NaOCl --> NaOH + NHCl₂

NHCl₂ + NaOCl --> NaOH + NCl₃

Additional reactions produce hydrazine, in a variation of the Olin Raschig process.

NH₃ + NH₂Cl + NaOH --> N₂H₄ + NaCl + H₂O

The hydrazine generated can further react with the monochloramine in an exothermic reaction:^[4]

2 NH₂Cl + N₂H₄ --> 2 NH₄Cl + N₂

Industrial bleaching agents can also be sources of concern. For example, the use of elemental chlorine in the bleaching of wood pulp produces organochlorines, persistent organic pollutants, including dioxins. According to an industry group, the use of chlorine dioxide in these processes has reduced the dioxin generation to under detectable levels.^[7] However, respiratory risk from chlorine and highly toxic chlorinated byproducts still exists.

A recent European study indicated that sodium hypochlorite and organic chemicals (e.g., surfactants, fragrances) contained in several household cleaning products can react to generate chlorinated volatile organic compounds (VOCs).^[8] These chlorinated compounds are emitted during cleaning applications, some of which are toxic and probable human carcinogens. The study showed that indoor air concentrations significantly increase (8-52 times for chloroform and 1-1170 times for carbon tetrachloride, respectively, above baseline quantities in the household) during the use of bleach containing products. The increase in chlorinated volatile organic compound concentrations was the lowest for plain bleach and the highest for the products in the form of “thick liquid and gel”. The significant increases observed in indoor air concentrations of several chlorinated VOCs (especially carbon tetrachloride and chloroform) indicate that the bleach use may be a source that could be important in terms of inhalation exposure to these compounds. While the authors suggested that using these cleaning products may significantly increase the cancer risk ^[9], this conclusion appears to be hypothetical:

• The highest level cited for concentration of carbon tetrachloride (seemingly of highest concern) is 459 micrograms per cubic meter, translating to 0.073 ppm (part per million), or 73 ppb (part per billion). The OSHA-allowable time-weighted average concentration over an eight-hour period is 10 ppm ^[10], almost 140 times higher;
• The OSHA highest allowable peak concentration (5 minute exposure for five minutes in a 4-hour period) is 200 ppm^[10], twice as high as the reported highest peak level (from the headspace of a bottle of a sample of bleach plus detergent).

Further studies of the use of these products and other possible exposure routes (i.e., dermal) may reveal other risks. Though the author further cited ozone depletion greenhouse effects for these gases, the very low amount of such gases, generated as prescribed, should minimize their contribution relative to other sources.

Chemistry

The process of bleaching can be summarized in the following set of chemical reactions:

Cl₂(aq) + H₂O(l) H⁺(aq) + Cl^-(aq) + HClO(aq)

The H⁺ ion of the hypochlorous acid then dissolves into solution, and so the final result is effectively:

Cl₂(aq) + H₂O(l) 2H⁺(aq) + Cl^-(aq) + ClO^-(aq)

Hypochlorite tends to decompose into chloride and a highly reactive form of oxygen:

ClO^- Cl^- + O

This oxygen then reacts with organic substances to produce bleaching or antiseptic effects.

Mechanism of bleach action

Color in most dyes and pigments is produced by molecules, such as beta carotene, which contain chromophores. Chemical bleaches work in one of two ways:

• An oxidizing bleach works by breaking the chemical bonds that make up the chromophore. This changes the molecule into a different substance that either does not contain a chromophore, or contains a chromophore that does not absorb visible light.

• A reducing bleach works by converting double bonds in the chromophore into single bonds. This eliminates the ability of the chromophore to absorb visible light.^[11]

Sunlight acts as a bleach through a process leading to similar results: high energy photons of light, often in the violet or ultraviolet range, can disrupt the bonds in the chromophore, rendering the resulting substance colorless. Extended exposure often leads to massive discoloration usually reducing the colors to white and typically very faded blue spectrums.^[12]

Sodium hypochlorite's anti-bacterial mechanism works by causing "shock" proteins to aggregate, which then fall off.^[13][14]

Antimicrobial efficacy

The broad-spectrum effectiveness of bleach, for example sodium hypochlorite, owes to the nature of the chemical reactivity of the bleach with the microbes. Rather than act in an inhibitory or specific toxic fashion in the manner of antibiotics, the reaction with the microbial cells quickly and irreversibly denatures, and often destroys the pathogen. Specifically, with sodium hypochlorite it is found that:

• the bleach attacks proteins in bacteria, causing them to clump up much like an egg that has been boiled,

• when exposed to bleach, the heat shock protein of bacteria become active in an attempt to protect other proteins in the bacteria from losing their chemical structure, forming clumps that would eventually die off, and

• the human immune system produces hypochlorous acid in response to infection to kill bacterial invaders

As noted, the range of micro-organisms effectively killed by bleach, and in particular sodium hypochlorite, is extensive, making it extremely versatile.

See also

• Disinfectant
• Household chemicals
• Tooth bleaching
• Bleaching of wood pulp
• Bleachfield

References

1. ^ "Ozone and Color Removal". Ozone Information. http://www.ozonesolutions.com/Ozone_Color_Removal.html. Retrieved on 2009-01-09. 
2. ^ "Risk Assessment Report for Sodium Hypochlorite". Association for Soaps, Detergents and Maintenance Products. http://ecb.jrc.it/DOCUMENTS/Existing-Chemicals/RISK_ASSESSMENT/DRAFT/R045_0711_env_hh.pdf. Retrieved on 2009-02-02. 
3. ^ "Risk Assessment Report for Sodium Hypochlorite". Scientific Committee on Health and Environmental Risks. http://ec.europa.eu/health/ph_risk/committees/04_scher/docs/scher_o_080.pdf. Retrieved on 2009-02-02. 
4. ^ ^{a b} Cotton, F.A; G. Wilkinson (1972). Advanced Inorganic Chemistry. John Wiley and Sons Inc. ISBN 0-471-17560-9. 
5. ^ Occupational Safety & Health Administration (2007). "and peroxide/recognition.html OSHA -- Chlorine". OSHA. http://www.osha.gov/SLTC/healthguidelines/chlorine and peroxide/recognition.html. Retrieved on 2007-08-26. 
6. ^ Rizk-Ouaini, Rosette; Ferriol, Michel; Gazet, Josette; Saugier-Cohen Adad, Marie Therese (1986), "Oxidation reaction of ammonia with sodium hypochlorite. Production and degradation reactions of chloramines.", Bulletin de la Societe Chimique de France 4: 512–21 
7. ^ "ECF: The Sustainable Technology". Alliance for Environmental Technology. http://www.aet.org/epp/ecf_brochure.pdf. Retrieved on 2007-09-19. 
8. ^ Odabasi, M., “Halogenated Volatile Organic Compounds from the Use of Chlorine-Bleach- Containing Household Products”, Environmental Science & Technology 42, 1445-1451, (2008). Available at: http://pubs.acs.org/journals/esthag/
9. ^ Odabasi, M., “Halogenated Volatile Organic Compounds from the Use of Chlorine-Bleach- Containing Household Products, Slide presentation (2008). Available at: http://www.slideworld.org/ViewSlides.aspx?URL=5092
10. ^ ^{a b} http://www.osha.gov/dts/chemicalsampling/data/CH_225800.html
11. ^ Field, Simon Q (2006). "Ingredients -- Bleach". Science Toys. http://sci-toys.com/ingredients/bleach.html. Retrieved on 2006-03-02. 
12. ^ Bloomfield, Louis A (2006). "Sunlight". How Things Work Home Page. http://howthingswork.virginia.edu/sunlight.html. Retrieved on 2006-03-02. 
13. ^ Reuters (2008). "Mystery solved: How bleach kills germs". MSNBC.com. http://www.msnbc.msn.com/id/27700273/. Retrieved on 2008-11-13. 
14. ^ Jakob, U.; J. Winter, M. Ilbert, P.C.F. Graf, and D. Özcelik (14 November 2008). "Bleach Activates a Redox-Regulated Chaperone by Oxidative Protein Unfolding". Cell (Elsevier) 135 (4): 691–701. doi:10.1016/j.cell.2008.09.024. http://www.cell.com/abstract/S0092-8674(08)01181-1. Retrieved on 2008-11-19. 

Further reading

• Bodkins, Dr. Bailey. Bleach. Philadelphia: Virginia Printing Press, 1995.
• Trotman, E.R. Textile Scouring and Bleaching. London: Charles Griffin & Co., 1968. ISBN 0852640676.
• Book in numerical format Knew you that?

External links

• American Chemistry Council, Chlorine Chemistry Division
• [1]

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

Dansk (Danish)
v. tr. - blege
v. intr. - bleg
n. - blegemiddel, affarvningsmiddel

Nederlands (Dutch)
bleekmiddel, (het) bleken

Français (French)
v. tr. - décolorer, oxygéner, (Phot) blanchir
v. intr. - blanchir, pâlir, oxygéner
n. - eau de Javel

Deutsch (German)
v. - bleichen, verbleichen
n. - Bleichmittel

Ελληνική (Greek)
v. - λευκαίνω, αποχρωματίζω, ασπρίζω, ξεβάφω
n. - αποχρωματισμός, λεύκανση, ξέβαμμα, λευκαντικό, (για κόμμωση) οξυζενάρισμα

Italiano (Italian)
candeggiare, scolorire

Português (Portuguese)
v. - alvejar
n. - branqueamento (m)

Русский (Russian)
отбеливать, обесцвечивать, выгорать

Español (Spanish)
v. tr. - decolorar, blanquear, aclarar el pelo, desteñir
v. intr. - descolorarse
n. - blanqueo, blanqueamiento

Svenska (Swedish)
v. - bleka, blondera, blekas, vitna
n. - blekmedel

中文（简体）(Chinese (Simplified))
漂白, 变白, 脱色, 变淡, 漂白法, 漂白剂

中文（繁體）(Chinese (Traditional))
v. tr. - 漂白
v. intr. - 變白, 脫色, 變淡
n. - 漂白, 漂白法, 漂白劑

한국어 (Korean)
v. tr. - ~을 표백하다
v. intr. - 하얗게 되다
n. - 표백[제]

日本語 (Japanese)
n. - 漂白剤
v. - 漂白する, 白くなる

العربيه (Arabic)
‏(فعل) قصر, بيض (الاسم) مادة قاصرة أو مبيضه‏

עברית (Hebrew)
v. tr. - ‮הלבין‬
v. intr. - ‮הלבין‬
n. - ‮חומר הלבנה‬

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