ホウ酸 化学特性,用途語,生産方法
外観
無色澄明の液体
溶解性
水及びエタノールにやや溶けやすい。
用途
調製液製造原料、無機合成(ほう酸塩製造)原料、ガラス原料、写真薬、殺虫剤。
用途
殺生物剤、セラミック、ゴム、難燃剤
用途
硝子、顔料
用途
緩衝液調製用(アミノ酸分析、蛍光分析）。
用途
汎用試薬、調製液製造原料。
用途
ガラス?ホウロウ原料、医薬、ニッケルメッキ添加剤、防火剤、防腐剤、写真薬
効能
眼科用消毒薬
特徴
平面三角形のBO3が水素結合で二次元網面を形成．B－O 136 pm，O－H 97 pm，O－H…O 272 pm
商品名
ホウ酸 (中北薬品); ホウ酸 (丸石製薬); ホウ酸 (健栄製薬); ホウ酸 (司生堂製薬); ホウ酸 (吉田製薬); ホウ酸 (山善製薬); ホウ酸 (恵美須薬品化工); ホウ酸 (日医工); ホウ酸 (日医工); ホウ酸 (日興製薬); ホウ酸 (東海製薬)
化学的特性
White powder or granules and odorless. It is incompatible with potassium, acetic anhydride, alkalis, carbonates, and hydroxides. Boric acid has uses in the production of textile fiberglass, flat panel displays, and eye drops. Boric acid is recognized for its application as a pH buffer and as a moderate antiseptic agent and emulsifier.
物理的性質
Colorless, transparent triclinic crystal or white granule or powder; density 1.435 g/cm
3; melts at 171°C under normal heating; however, slow heating causes loss of water; sparingly soluble in cold water (4.7% at 20°C); pH of 0.1M solution 5.1; readily dissolves in hot water (19.1% at 80°C and 27.5% at 100°C); also soluble in lower alcohols and moderately soluble in pyridine.
使用
For weatherproofing wood and fireproofing fabrics; as a preservative; manufacture of cements, crockery, porcelain, enamels, glass, borates, leather, carpets, hats, soaps, artificial gems; in nickeling baths; cosmetics; printing and dyeing, painting; photography; for impregnating wicks; electric condensers; hardening steel. Also used as insecticide for cockroaches and black carpet beetles.
調製方法
Boric acid occurs naturally as the mineral sassolite. However, the
majority of boric acid is produced by reacting inorganic borates
with sulfuric acid in an aqueous medium. Sodium borate and
partially refined calcium borate (colemanite) are the principal raw
materials. When boric acid is made from colemanite, the fineground
ore is vigorously stirred with mother liquor and sulfuric acid
at about 908℃. The by-product calcium sulfate is removed by
filtration, and the boric acid is crystallized by cooling the filtrate.
製造方法
Boric acid is produced from borax, colemanite, or other inorganic borates by reaction with sulfuric acid or hydrochloric acid, and cooling the solution to proper temperature:
Na
2B
4O
7 ? 10Η
2Ο + H
2SO
4 → 4H
3BO
3 + Na
2SO
4 + 5H
2O
It also may be prepared by extraction of weak borax brine with a kerosene solution of an aromatic diol, such as 2-ethyl-1,3-hexanediol or 3-chloro- 2-hydroxy-5-(1,1,3,3-tetramethylbutyl)benzyl alcohol. The diol-borate chelate formed separates into a kerosene phase. Treatment with sulfuric acid yields boric acid which partitions into aqueous phase and is purified by recrystallization.
世界保健機関（WHO）
Boric acid and some borates were formerly extensively used as
disinfectants and antiinflammatory agents. By the late 1960s an association between
the death of many infants and application of high concentrations of boric acid
contained in topical preparations used in the treatment of napkin rash had been
established. This led to the restriction of the use of boric acid in pharmaceutical
preparations by many regulatory authorities. In some countries it is now permitted
only as an ingredient in ophthalmological preparations.
一般的な説明
Boric acid is a weak monobasic acid, it accepts OH
- ions, hence is a Lewis acid. In boric acid, B is sp
2 hybridized, forming a planar triangle structure. The principal oxide of boron, B
2O
3, is obtained as a vitreous solid by dehydration of boric acid at red heat.
危険性
Toxic via ingestion. Use only weak solu-
tions. Irritant to skin in dry form.
応用例（製薬）
Boric acid is used as an antimicrobial preservative in eye drops,
cosmetic products, ointments, and topical creams. It is also used as
an antimicrobial preservative in foods.
Boric acid and borate have good buffering capacity and are used
to control pH; they have been used for this purpose in external
preparations such as eye drops.
Boric acid has also been used therapeutically in the form of
suppositories to treat yeast infections. In dilute concentrations it
is used as a mild antiseptic, with weak bacteriostatic and fungistatic
properties, although it has generally been superseded by more
effective and less toxic disinfectants.
職業ばく露
Boric acid is a fireproofing agent for
wood; a preservative, and an antiseptic. It is used in the
manufacture of glass, pottery, enamels, glazes, cosmetics,
cements, porcelain, borates, leather, carpets, hats, soaps;
artificial gems; in tanning leather; printing, dyeing, painting,
and photography.
貯蔵
Boric acid is hygroscopic and should therefore be stored in an airtight,
sealed container. The container must be labeled ‘Not for
Internal Use’.
輸送方法
UN 3077 Environmentally hazardous substances,
solid, n.o.s., Hazard class: 9; Labels: 9—Miscellaneous
hazardous material, Technical Name Required.
純化方法
Crystallise the acid three times from H2O (3mL/g) between 100o and 0o, after filtering through sintered glass.Dry it to constant weight over metaboric acid in a desiccator. It is steam volatile. After two recrystallisations of ACS grade. it had Ag at 0.2 ppm. Its solubility (%) in H2O is 2.66 at 0o, 4.0 at 12o and 24 at 80o. At 100o it loses H2O to form metaboric acid (HBO2). When it is heated to redness or slowly to 200o, or over P2O5 in vacuo, it dehydrates to boric anhydride (B2O3) [1303-82-6] to give a white hard glass or crystals with m ~294o.The glass softens on heating and liquefies at red heat. It is an astringent, a fungicide and an antibacterial.
[McCulloch J Am Chem Soc 59 2650 1937, Kelly J Am Chem Soc 63 1137 1941, Taylor & Cole J Chem Soc 70 1926, Conti J Soc Chem Ind 44 343T 1925.]
不和合性
Boric acid decomposes in heat above
100 C, forming boric anhydride and water. Boric acid is
hygroscopic; it will absorb moisture from the air. Boric
acid aqueous solution is a weak acid; incompatible with
strong reducing agents including alkali metals and metal
hydrides (may generate explosive hydrogen gas); acetic
anhydride, alkali carbonates, and hydroxides. Violent
reaction with powdered potassium metal, especially if
impacted. Attacks iron in the presence of moisture.
廃棄物の処理
Boric acids may be recovered
from organic process wastes as an alternative to disposal.
規制状況(Regulatory Status)
Accepted for use as a food additive in Europe. Included in the FDA
Inactive Ingredients Database (IV injections; ophthalmic preparations;
(auricular) otic solutions; topical preparations). Reported in
the EPA TSCA Inventory. In the UK, the use of boric acid in
cosmetics and toiletries is restricted. Included in the Canadian List
of Acceptable Non-medicinal Ingredients.
参考文献
W.H. Zachariasen, Acta Crystallogr., 7, 305 (1954), DOI: 10.1107/S0365110X54000886.
ホウ酸 上流と下流の製品情報
原材料
準備製品
ホウフッ化
亜鉛·2テトラフルオロボラート
水素化ナトリウム
酸化ほう素
ほう酸トリイソプロパノールアミン
グリコール酸メチル
6‐キノリニルメタノール
ほう酸 トリエタノールアミン
ニトロメタン
ホウフッ化カリウム
Foliar-fertilizer
ホウ酸亜鉛
ほう酸トリブチル
3-(トリフルオロメチル)けい皮酸メチルエステル
ホウフッ化ソーダ
水素化ほう素ナトリウム
3,3'-[(9,10-ジヒドロ-9,10-ジオキソアントラセン-1,4-ジイル)ジイミノ]ビス[2,4,6-トリメチルベンゼンスルホン酸ナトリウム]
テトラフェニルほう酸ナトリウム
4-オキソ-5,5,5-トリフルオロ吉草酸メチル
ボロントリフルオリド - エチルエーテル コンプレックス
Yemianbao
ホウフッ化水素酸
水素化ほう素カリウム
キニザリン
6-メトキシキノリン
六フッ化アルミニウムカリウム
2-フェノキシ-1-アミノ-4-ヒドロキシアントラセン-9,10-ジオン
ホウフッ化アンモニウム
［［［２,２',２”-ニトリロトリス［エタノラト］］（３-）-Ｎ,Ｏ,Ｏ',Ｏ”］-ホウ素
窒化ホウ素