りん酸水素カルシウム 化学特性,用途語,生産方法
外観
白色の結晶又は粉末
定義
本品は、リン酸(*)の二カルシウム塩であり、次の化学式で表される。
参照表示名称:リン酸
溶解性
水に難溶、酸に可溶、エタノールに不溶。
解説
リン酸水素カルシウム(calcium (mono)hydrogenphosphate):CaHPO4(136.06).略称DCP.第二リン酸カルシウムともいう.リン酸二水素ナトリウムとリン酸二水素カリウムの水溶液に,塩化カルシウム水溶液を加え,pH を4~5に保つと二水和物として得られる.工業的には,石灰乳をリン酸で中和してつくる.二水和物[CAS 7789-77-7]は,無色のりん片状の六方晶系または斜方晶系結晶.密度2.31 g cm-3.水に難溶,エタノールに不溶,塩酸,硝酸に可溶.36 ℃ 以上で徐々に無水和物になる.無水和物は,三斜晶系結晶.密度2.892 g cm-3.水に難溶,塩酸,硝酸に易溶.二酸化炭素を含む水には少量溶ける.歯磨き用研磨剤として二水和物が大量に使用されている.ベーキングパウダー助剤,食品のカルシウム補給,医薬原料,動物飼料の添加剤などとして使用される.
用途
食品のCa強化剤。
用途
合成ゴム重合用、ガソリン重合用、カルシウム補給剤、歯磨き基剤
化粧品の成分用途
不透明化剤、口腔ケア剤、研磨.スクラブ剤
効能
カルシウム補充薬, 賦形剤
化学的特性
Anhydrous dibasic calcium phosphate is a white, odorless, tasteless
powder or crystalline solid. It occurs as triclinic crystals.
物理的性質
White triclinic crystal; density 2.92 g/cm
3 (anhydrous) and 2.31 g/cm
3 (dihy drate); hardness 3.5 Mohs; decomposes on heating; inosluble in water and alcohol; KSP 2.7x10
-7; soluble in dilute mineral acid.
使用
Replenisher
(calcium); pharmaceutic aid (tablet base).
調製方法
Calcium phosphates are usually prepared by reacting very pure
phosphoric acid with calcium hydroxide, Ca(OH)
2 obtained from
limestone, in stoichiometric ratio in aqueous suspension followed
by drying at a temperature that will allow the correct hydration
state to be achieved. After drying, the coarse-grade material is
obtained by means of a classification unit; the fine particle-size
material is obtained by milling. Dibasic calcium phosphate,
anhydrous, may also be prepared by spray-drying.
农业用途
Dicalcium phosphate (CaHPO
4) is made from calcium carbonate and phosphoric acid. It contains 34% citrate- soluble phosphorus pentoxide (P
2O
5). It is not commonly used as a fertilizer, but is used as a supplement to animal feed.
応用例(製薬)
Anhydrous dibasic calcium phosphate is used both as an excipient
and as a source of calcium in nutritional supplements. It is used
particularly in the nutritional/health food sectors. It is also used in
pharmaceutical products because of its compaction properties, and
the good flow properties of the coarse-grade material. The
predominant deformation mechanism of anhydrous dibasic calcium
phosphate coarse-grade is brittle fracture and this reduces the
strain-rate sensitivity of the material, thus allowing easier transition
from the laboratory to production scale. However, unlike the
dihydrate, anhydrous dibasic calcium phosphate when compacted
at higher pressures can exhibit lamination and capping. This
phenomenon can be observed when the material represents a
substantial proportion of the formulation, and is exacerbated by the
use of deep concave tooling. This phenomenon also appears to be
independent of rate of compaction.
Anhydrous dibasic calcium phosphate is abrasive and a lubricant
is required for tableting, for example 1% w/w magnesium stearate
or 1% w/w sodium stearyl fumarate.
Two particle-size grades of anhydrous dibasic calcium phosphate
are used in the pharmaceutical industry. Milled material is typically
used in wet-granulated or roller-compacted formulations. The
‘unmilled’ or coarse-grade material is typically used in directcompression
formulations.
Anhydrous dibasic calcium phosphate is nonhygroscopic and
stable at room temperature. It does not hydrate to form the
dihydrate.
Anhydrous dibasic calcium phosphate is used in toothpaste and
dentifrice formulations for its abrasive properties.
安全性プロファイル
Skin and eye irritant. A
nuisance dust.
安全性
Dibasic calcium phosphate anhydrous is widely used in oral
pharmaceutical products, food products, and toothpastes, and is
generally regarded as a relatively nontoxic and nonirritant material.
貯蔵
Dibasic calcium phosphate anhydrous is a nonhygroscopic,
relatively stable material. Under conditions of high humidity it
does not hydrate to form the dihydrate.
The bulk material should be stored in a well-closed container in a
dry place.
純化方法
Crystallise it from a near-saturated solution in 50% aqueous reagent grade phosphoric acid at 100o by filtering through fritted glass and cooling to room temperature. The crystals are filtered off, and this process is repeated three times using fresh acid. For the final crystallisation the solution is cooled slowly with constant stirring to give thin plate crystals that are filtered off on a fritted glass funnel, washed free of acid with anhydrous acetone and dry in a vacuum desiccator [Egan et al.J Am Chem Soc 78 1811 1956].
不和合性
Dibasic calcium phosphate should not be used to formulate
tetracyline antibiotics.
The surface of milled anhydrous dibasic calcium phosphate is
alkaline and consequently it should not be used with drugs that
are sensitive to alkaline pH. However, reports suggest there are
differences in the surface alkalinity/acidity between the milled and
unmilled grades of anhydrous dibasic calcium phosphate; the
unmilled form has an acidic surface environment. This difference
has important implications for drug stability, particularly when
reformulating from, e.g. roller compaction to direct compression,
when the particle size of the anhydrous dibasic calcium phosphate
might be expected to change.
Dibasic calcium phosphate dihydrate has been reported to be
incompatible with a number of drugs and excipients, and many of
these incompatibilities are expected to occur with dibasic calcium
phosphate, anhydrous; see Calcium phosphate, dibasic dihydrate.
規制状況(Regulatory Status)
GRAS listed. Accepted as a food additive in Europe. Included in the
FDA Inactive Ingredients Database (oral capsules and tablets).
Included in nonparenteral medicines licensed in Europe. Included in
the Canadian List of Acceptable Non-medicinal Ingredients.
りん酸水素カルシウム 上流と下流の製品情報
原材料
準備製品