US3411873A - Process for the stabilization of dicalciumphosphate dihydrate - Google Patents
Process for the stabilization of dicalciumphosphate dihydrate Download PDFInfo
- Publication number
- US3411873A US3411873A US597875A US59787566A US3411873A US 3411873 A US3411873 A US 3411873A US 597875 A US597875 A US 597875A US 59787566 A US59787566 A US 59787566A US 3411873 A US3411873 A US 3411873A
- Authority
- US
- United States
- Prior art keywords
- weight
- phosphate
- magnesium
- pyrophosphate
- dihydrate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- RBLGLDWTCZMLRW-UHFFFAOYSA-K dicalcium phosphate dihydrate Substances O.O.[Ca+2].[Ca+2].[O-]P([O-])([O-])=O RBLGLDWTCZMLRW-UHFFFAOYSA-K 0.000 title description 25
- 238000000034 method Methods 0.000 title description 15
- 230000006641 stabilisation Effects 0.000 title description 7
- 238000011105 stabilization Methods 0.000 title description 7
- FUFJGUQYACFECW-UHFFFAOYSA-L calcium hydrogenphosphate Chemical compound [Ca+2].OP([O-])([O-])=O FUFJGUQYACFECW-UHFFFAOYSA-L 0.000 title 1
- 235000011180 diphosphates Nutrition 0.000 description 17
- 229940048084 pyrophosphate Drugs 0.000 description 17
- 239000003381 stabilizer Substances 0.000 description 12
- 229910052783 alkali metal Inorganic materials 0.000 description 11
- MXZRMHIULZDAKC-UHFFFAOYSA-L ammonium magnesium phosphate Chemical compound [NH4+].[Mg+2].[O-]P([O-])([O-])=O MXZRMHIULZDAKC-UHFFFAOYSA-L 0.000 description 11
- 229910052567 struvite Inorganic materials 0.000 description 11
- -1 alkali metal tripolyphosphate Chemical class 0.000 description 9
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 9
- XPPKVPWEQAFLFU-UHFFFAOYSA-J diphosphate(4-) Chemical compound [O-]P([O-])(=O)OP([O-])([O-])=O XPPKVPWEQAFLFU-UHFFFAOYSA-J 0.000 description 9
- 235000019739 Dicalciumphosphate Nutrition 0.000 description 8
- 150000001340 alkali metals Chemical class 0.000 description 8
- 239000001506 calcium phosphate Substances 0.000 description 8
- NEFBYIFKOOEVPA-UHFFFAOYSA-K dicalcium phosphate Chemical compound [Ca+2].[Ca+2].[O-]P([O-])([O-])=O NEFBYIFKOOEVPA-UHFFFAOYSA-K 0.000 description 8
- 229940038472 dicalcium phosphate Drugs 0.000 description 8
- 229910000390 dicalcium phosphate Inorganic materials 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- 229910019142 PO4 Inorganic materials 0.000 description 7
- CKRORYDHXIRZCH-UHFFFAOYSA-N phosphoric acid;dihydrate Chemical compound O.O.OP(O)(O)=O CKRORYDHXIRZCH-UHFFFAOYSA-N 0.000 description 7
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 6
- 235000021317 phosphate Nutrition 0.000 description 6
- 239000010452 phosphate Substances 0.000 description 5
- 230000000087 stabilizing effect Effects 0.000 description 5
- 239000000203 mixture Substances 0.000 description 4
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- 229910017958 MgNH Inorganic materials 0.000 description 3
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- GVALZJMUIHGIMD-UHFFFAOYSA-H magnesium phosphate Chemical compound [Mg+2].[Mg+2].[Mg+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O GVALZJMUIHGIMD-UHFFFAOYSA-H 0.000 description 3
- 239000004137 magnesium phosphate Substances 0.000 description 3
- 229910000157 magnesium phosphate Inorganic materials 0.000 description 3
- 229960002261 magnesium phosphate Drugs 0.000 description 3
- 235000010994 magnesium phosphates Nutrition 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- CKMXBZGNNVIXHC-UHFFFAOYSA-L ammonium magnesium phosphate hexahydrate Chemical compound [NH4+].O.O.O.O.O.O.[Mg+2].[O-]P([O-])([O-])=O CKMXBZGNNVIXHC-UHFFFAOYSA-L 0.000 description 2
- DRMWBNMSWMDKLG-UHFFFAOYSA-L ammonium magnesium phosphate monohydrate Chemical compound [NH4+].O.[Mg+2].[O-]P([O-])([O-])=O DRMWBNMSWMDKLG-UHFFFAOYSA-L 0.000 description 2
- 239000001110 calcium chloride Substances 0.000 description 2
- 229910001628 calcium chloride Inorganic materials 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 2
- FQENQNTWSFEDLI-UHFFFAOYSA-J sodium diphosphate Chemical compound [Na+].[Na+].[Na+].[Na+].[O-]P([O-])(=O)OP([O-])([O-])=O FQENQNTWSFEDLI-UHFFFAOYSA-J 0.000 description 2
- 229940048086 sodium pyrophosphate Drugs 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 235000019818 tetrasodium diphosphate Nutrition 0.000 description 2
- 239000001577 tetrasodium phosphonato phosphate Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- POCPYOMYXRMNGX-UHFFFAOYSA-J calcium;disodium;phosphonato phosphate Chemical class [Na+].[Na+].[Ca+2].[O-]P([O-])(=O)OP([O-])([O-])=O POCPYOMYXRMNGX-UHFFFAOYSA-J 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000002537 cosmetic Substances 0.000 description 1
- PJQJKHNLFUSIGI-UHFFFAOYSA-K dimagnesium phosphate trihydrate Chemical compound O.O.O.[Mg+2].[Mg+2].[O-]P([O-])([O-])=O PJQJKHNLFUSIGI-UHFFFAOYSA-K 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000012065 filter cake Substances 0.000 description 1
- 229940005740 hexametaphosphate Drugs 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 150000002681 magnesium compounds Chemical class 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 235000019832 sodium triphosphate Nutrition 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000000606 toothpaste Substances 0.000 description 1
- 229940034610 toothpaste Drugs 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/16—Oxyacids of phosphorus; Salts thereof
- C01B25/26—Phosphates
- C01B25/32—Phosphates of magnesium, calcium, strontium, or barium
- C01B25/327—After-treatment
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K8/00—Cosmetics or similar toiletry preparations
- A61K8/18—Cosmetics or similar toiletry preparations characterised by the composition
- A61K8/19—Cosmetics or similar toiletry preparations characterised by the composition containing inorganic ingredients
- A61K8/24—Phosphorous; Compounds thereof
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61Q—SPECIFIC USE OF COSMETICS OR SIMILAR TOILETRY PREPARATIONS
- A61Q11/00—Preparations for care of the teeth, of the oral cavity or of dentures; Dentifrices, e.g. toothpastes; Mouth rinses
Definitions
- Dicalcium phosphate dihydrate particularly dicalcium phosphate dihydrate used for cosmetic or medicinal preparations, is known to be stabilizable.
- the stabilization agents used for that purpose include, for example, tetrasodium-, calcium-, magnesiumas Well as calcium disodium-pyrophosphates, alkali metal tripolyphosphate, alkali metal hexametaphosphate, diand trimagnesiurn phosphates, which are used alone or in combination.
- Dicalcium phosphate dihydrate stabilized by means of these substances has however sometimes been found to have an unsatisfactory stability, especially for use in fluoride-containing tooth paste.
- a method for stabilizing dicalcinm phosphate dihydrate by admixing therewith an effective stabilizing amount of a magnesium-ammonium phosphate can be combined with an alkali metal pyrophosphate or an alkaline earth metal pyrophosphate.
- the stabilization of dicalcinm phosphate dihydrate can be improved by using a magnesium-ammonium phosphate, for example magnesium-ammonium phosphate hexahydrate, as the stabilizer which is preferably used in combination with an alkali metal or alkaline earth metal pyrophosphate.
- a magnesium-ammonium phosphate for example magnesium-ammonium phosphate hexahydrate
- the dicalcium phosphate dihydrate should advantageously be stabilized by incorporating therewith 0.4 to 0.9% by weight, preferably 0.8% by weight, alkali metal or alkaline earth metal pyrophosphate and a proportion of magnesium-ammonium phosphate sufiicient to result in the formation of dicalcinm phosphate dihydrate with a MgO-content between 0.2 and at most 0.4% by weight, preferably of 0.3% by weight.
- the stabilizers can readily be introduced into the reactor during the production of the dicalcinm phosphate but before isolation thereof, at a pH-value between 7.5 and 8.5.
- the dicalcium phosphate is mixed during its preparation with 0.1 to 0.4% by weight, preferably with 0.3% by weight alkali metal or alkali earth metal, pyrophosphate, referred to the dicalcinm phosphate dihydrate, and with a proportion of magnesium-ammonium phosphate sufficient to result in the formation of dicalcinm phosphate dihydrate with a content of MgO between 0.2 and at most 0.4% by weight, preferably of 0.3% by weight, and the isolated and dried product is mixed subsequently with 0.4% by weight alkali metal or alkali earth metal pyrophosphate to be ground then into particles of predetermined size.
- the magnesium-ammonium phosphate proportion can 3,411,873 Patented Nov. 19, 1968 "ice also be mixed first with solid, dry
- Quantity Stabilizer calculated pH pH in percent (20 C.) ("20 C MgO 0. 0 7. 1 4. 7 lUgNHrPOr-HaO 0. 1 7. 4 5. 45
- a further advantage associated with the process of the present invention resides in the fact that considerably lesser proportions of alkali metal or alkaline earth metal pyrophosphate are needed for producing the stabilization.
- EXAMPLE 1 A reactor provided with a rapid propeller stirrer was filled with 220 liters Water. 100 kg. CaCO were simultaneously suspended in a second container; the CaCO suspension had a density of about 1.3 to 1.5 g./cc. In a first step, the carbonate suspension and phosphoric acid having a strength of 70 to by weight were simultaneously pumped into the reactor. The phosphoric acid was supplied at a rate such that the pH-value varied between 2.3 and 2.6.
- the pH-value was finally adjusted in a second step by reaction of the phosphoric acid in excess with calcium chloride (25-35% strength by weight) and sodium hydroxide solution (20S0% strength by weight) in stoichiometric proportions.
- the temperature inside the reactor was found to increase from initially 2530 C. (first step) to 40-45 C.
- the supply of calcium chloride and sodium hydroxide solution was arrested, and the material was stabilized subsequently by adding 0.3% MgO in the form of and Na4P207.
- the dicalcium phosphate was filtered off and Washed.
- the filter cake was dried in a fluidized bed drier, mixed with 0.4% by weight sodium pyrophosphate and ground in a sifter bowl mill to obtain particles of which 99.5% had a size of 40,u.
- the sodium pyrophosphate should be used in the form of particles of which about 60 to 80% have a size of 40 i.e., a size corresponding to that of the dicalcium phosphate obtained.
- EXAMPLE 2 The procedure and conditions were the same as those used in Example 1, save that the MgNH PO -H O was replaced with an equivalent proportion of M gNH PO 6H O
- EXAMPLE 3 The reaction procedure and conditions were the same as those used in Example 1, save that the 0.3% by weight MgNH PO -H O were mixed with dried dicalcium phosphate and ground, rather than introduced into the reactor at a pH-value of 8.0.
- the magnesium phosphate should be used in the form of particles of which about 45 to 90% have a size of 45p., i.e., a size corresponding to that of the dicalcium phosphate obtained.
- EXAMPLE 4 The procedure and conditions were analogous to those used in Example 3, save that the MgNH PO -H O was replaced with an equivalent proportion of her selected from the group consisting of alkali metal pyrophosphate and alkaline earth metal pyrophosphate as a stabilizer.
- stabilization is effected by admixing 0.40.9% by weight of an alkali metal or alkaline earth metal pyrophosphate with an amount of magnesium-ammonium phosphate suflicient to effect formation of dicalcium phosphate dihydrate having a MgO content of 0.20.4% by weight.
- dicalcium phosphate dihydrate is stabilized by adding 0.8% by weight pyrophosphate and an amount of magnesium-ammonium phosphate sufiicient to effect formation of dicalcium phosphate dihydrate having a MgO content of 0.3% by weight.
- magnesium-ammonium phosphate is first mixed with solid dry dicalcium phosphate, the mixture being thereafter ground into particles of predetermined size.
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Public Health (AREA)
- Animal Behavior & Ethology (AREA)
- Inorganic Chemistry (AREA)
- Organic Chemistry (AREA)
- General Health & Medical Sciences (AREA)
- Veterinary Medicine (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Epidemiology (AREA)
- Geology (AREA)
- Birds (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Cosmetics (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEK57982A DE1277222B (de) | 1965-12-22 | 1965-12-22 | Verfahren zur Stabilisierung von Dicalciumphosphatdihydrat |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3411873A true US3411873A (en) | 1968-11-19 |
Family
ID=7228495
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US597875A Expired - Lifetime US3411873A (en) | 1965-12-22 | 1966-11-30 | Process for the stabilization of dicalciumphosphate dihydrate |
Country Status (10)
| Country | Link |
|---|---|
| US (1) | US3411873A (en, 2012) |
| AT (1) | AT268201B (en, 2012) |
| BE (1) | BE691661A (en, 2012) |
| CH (1) | CH483992A (en, 2012) |
| DE (1) | DE1277222B (en, 2012) |
| DK (1) | DK133371B (en, 2012) |
| FR (1) | FR1505987A (en, 2012) |
| GB (1) | GB1106447A (en, 2012) |
| NL (1) | NL158144B (en, 2012) |
| SE (1) | SE300967B (en, 2012) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4193973A (en) * | 1978-12-22 | 1980-03-18 | Monsanto Company | Process for stabilization of dicalcium phosphate |
| EP0045826A1 (en) * | 1980-08-12 | 1982-02-17 | Monsanto Company | Dicalcium phosphate dihydrate having improved stability and a method for preparing it |
| EP0240880A3 (en) * | 1986-04-07 | 1988-03-30 | Stauffer Chemical Company | Dicalcium phosphate dihydrate for fluoride dentifrice compositions |
| EP0475482A1 (en) | 1990-09-13 | 1992-03-18 | Akzo Nobel N.V. | Stabilized solid chemical compositions |
| US5292520A (en) * | 1990-09-13 | 1994-03-08 | Akzo N.V. | Stabilized solid pharmaceutical composition containing acid addition salts of a basic drug and an alkaline stabilizer |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2648061C2 (de) * | 1976-10-23 | 1982-11-04 | Hoechst Ag, 6000 Frankfurt | Verfahren zum Stabilisieren von Di-calciumhydrogenphosphatdihydrat |
| US4472365A (en) * | 1981-06-15 | 1984-09-18 | Stauffer Chemical Company | Dicalcium phosphate dihydrate having improved monofluorophosphate compatibility and process for the preparation thereof |
| GB2112762B (en) * | 1981-12-31 | 1985-05-01 | Stauffer Chemical Co | Dicalcium phosphate dihydrate having improved monofluorophosphate compatibility |
| JP2004230907A (ja) | 2002-02-01 | 2004-08-19 | Topy Ind Ltd | 建設機械用ローラー部品構造 |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1189527B (de) * | 1959-06-30 | 1965-03-25 | Stauffer Chemical Co | Verfahren zur Herstellung von stabilisiertem Dicalciumphosphat |
-
1965
- 1965-12-22 DE DEK57982A patent/DE1277222B/de active Pending
-
1966
- 1966-10-14 SE SE14005/66D patent/SE300967B/xx unknown
- 1966-11-10 CH CH1616766A patent/CH483992A/de not_active IP Right Cessation
- 1966-11-30 US US597875A patent/US3411873A/en not_active Expired - Lifetime
- 1966-12-07 GB GB54818/66A patent/GB1106447A/en not_active Expired
- 1966-12-21 AT AT1173366A patent/AT268201B/de active
- 1966-12-21 NL NL6617958.A patent/NL158144B/xx not_active IP Right Cessation
- 1966-12-21 DK DK661466AA patent/DK133371B/da not_active IP Right Cessation
- 1966-12-22 BE BE691661D patent/BE691661A/xx unknown
- 1966-12-22 FR FR88529A patent/FR1505987A/fr not_active Expired
Non-Patent Citations (1)
| Title |
|---|
| None * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4193973A (en) * | 1978-12-22 | 1980-03-18 | Monsanto Company | Process for stabilization of dicalcium phosphate |
| EP0045826A1 (en) * | 1980-08-12 | 1982-02-17 | Monsanto Company | Dicalcium phosphate dihydrate having improved stability and a method for preparing it |
| EP0240880A3 (en) * | 1986-04-07 | 1988-03-30 | Stauffer Chemical Company | Dicalcium phosphate dihydrate for fluoride dentifrice compositions |
| EP0475482A1 (en) | 1990-09-13 | 1992-03-18 | Akzo Nobel N.V. | Stabilized solid chemical compositions |
| US5292520A (en) * | 1990-09-13 | 1994-03-08 | Akzo N.V. | Stabilized solid pharmaceutical composition containing acid addition salts of a basic drug and an alkaline stabilizer |
| US5441747A (en) * | 1990-09-13 | 1995-08-15 | Akzo N.V. | Stabilized solid pharmaceutical composition containing acid addition salts of a basic drug and an alkaline stabilizer |
Also Published As
| Publication number | Publication date |
|---|---|
| DE1277222B (de) | 1968-09-12 |
| AT268201B (de) | 1969-02-10 |
| NL158144B (nl) | 1978-10-16 |
| CH483992A (de) | 1970-01-15 |
| DK133371B (da) | 1976-05-10 |
| FR1505987A (fr) | 1967-12-15 |
| GB1106447A (en) | 1968-03-20 |
| NL6617958A (en, 2012) | 1967-06-23 |
| DK133371C (en, 2012) | 1976-10-04 |
| BE691661A (en, 2012) | 1967-05-29 |
| SE300967B (en, 2012) | 1968-05-20 |
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