บอแรกเป็นสารประกอบที่สำคัญของโบรอน ชื่อสามัญ น้ำประสานทอง หรือผงเนื้อกรอบ หรือเพ่งแซ เมื่อถ้าอยู่ในรูปผลึกบริสุทธิ์จะไม่มีสี ถ้านำไปเผาต่อจนไม่มีน้ำอยู่ในโมเลกุลจะเรียกน้ำประสานทองสะตุ เป็นผงมีสีขาว ละลายน้ำได้ง่าย
Bor@x, also known as sodium borate, sodium tetraborate, or disodium tetraborate, is an important boron compound, a mineral, and a salt of boric acid. Powdered bor@x is white, consisting of soft colorless crystals that dissolve in water. A number of closely related minerals or chemical compounds that differ in their crystal water content are referred to as bor@x, and the word is usually used to refer to the octahydrate. Commercially sold bor@x is partially dehydrated.
Bor@x is a component of many detergents, cosmetics, and enamel glazes. It is used to make buffer solutions in biochemistry, as a fire retardant, as an anti-fungal compound, in the manufacture of fiberglass, as a flux in metallurgy, neutron-capture shields for radioactive sources, a texturing agent in cooking, as a cross-linking agent in slime, as an alkali in photographic developers, as a precursor for other boron compounds, and along with its inverse, boric acid, is useful as an insecticide.
Bor@x was first discovered in dry lake beds in Tibet and was imported via the Silk Road to the Arabian Peninsula in the 8th century AD. Bor@x first came into common use in the late 19th century when Francis Marion Smith's Pacific Coast Bor@x Company began to market and popularize a large variety of applications under the 20 Mule Team Bor@x trademark, named for the method by which bor@x was originally hauled out of the California and Nevada deserts.
Natural sources
Bor@x occurs naturally in evaporite deposits produced by the repeated evaporation of seasonal lakes. The most commercially important deposits are found in: Turkey; Boron, California; and Searles Lake, California. Also, bor@x has been found at many other locations in the Southwestern United States, the Atacama desert in Chile, newly discovered deposits in Bolivia, and in Tibet and Romania.
Household products
Bor@x is used in various household laundry and cleaning products, including the "20 Mule Team Bor@x" laundry booster, "Bor@x" powdered hand soap, and some tooth bleaching formulas.
Food additive
Bor@x, given the E number E285, is used as a food additive, but is banned in some countries, such as the United States, China, and Thailand. As a consequence, certain foods, such as caviar, produced for sale in the United States contain higher levels of salt to assist preservation. In addition to its use as a preservative, Bor@x imparts a firm, rubbery texture to food. In China, Bor@x has been found in foods including wheat and rice noodles named; lamian, shahe fen, kway teow, and chee cheong fun. In Indonesia, it is a common, but forbidden, additive to such foods as noodles, bakso (meatballs), and steamed rice. The country's Directorate of Consumer Protection warns of the risk of liver cancer with high consumption over a period of five to ten years.
Other uses
Medicinal
- Anti-fungal foot soak
- Treatment for thrush in horses' hoofs
- Is found in some commercial vitamin supplements
Other
- Ingredient in enamel glazes
- Component of glass, pottery, and ceramics
- Used as an additive in ceramic slips and glazes to improve fit on wet, greenware, and bisque
- Fire retardant
- Anti-fungal compound for cellulose insulation
- Moth proofing 10% solution for wool
- Pulverized for the prevention of stubborn pests (e.g. German cockroaches) in closets, pipe and cable inlets, wall panelling gaps, and inaccessible locations where ordinary pesticides are undesirable
- Precursor for sodium perborate monohydrate that is used in detergents, as well as for boric acid and other borates
- Tackifier ingredient in casein, starch and dextrin based adhesives
- Precursor for boric acid, a tackifier ingredient in polyvinyl acetate, polyvinyl alcohol based adhesives
- Fluoride detoxification
- To make indelible ink for dip pens by dissolving shellac into heated Bor@x
- Curing agent for snake skins
- Curing agent for salmon eggs, for use in sport fishing for salmon
- Swimming pool buffering agent to control pH
- Neutron absorber, used in nuclear reactors and spent fuel pools to control reactivity and to shut down a nuclear chain reaction
- As a micronutrient fertilizer to correct boron-deficient soils.
- Preservative in taxidermy
- To color fires with a green tint
- Was traditionally used to coat dry-cured meats such as hams to improve the appearance and discourage flies.
- For stopping car radiator and engine block leaks
- Used by blacksmiths in forge welding
- Used as a woodworm treatment (diluted in water)