Stannous fluoride SnF2
Name: Stannous fluoride
CAS No.: 7783-47-3
Appearance: White monoclinic crystal
Purity: 99.9%, 99%, 94%
Molecular formula: SnF2
Melting point: 215℃
Boiling point: 850℃
Packing: 25kg/bag
Stannous fluoride Description
Tin(II) fluoride properties
Relative molecular weight: 156.69
Density: 4.75g/cm3
Soluble in cold water and hydrofluoric acid. Easily hydrolyzed and oxidized in water.
Tin(II) fluoride security
Acute toxicity LD50. It is 377mg/kg (rat oral administration), which is a harmful chemical [3]. According to the national standard “Specification for Raw Materials Used in Toothpaste (GB 22115-2008)”, stannous fluoride can be used in limited amounts in toothpaste.
Tin(II) fluoride quality standard
| Specifications | Electronic grade | Toothpaste grade | Pharmaceutical Grade |
| Implementation standards | SEMI C1 | Yotech Standard | USP-34 |
| Content | ≥99.9％ | ≥99.0％ | ≥94.0％ |
| Sn ％ | ≥75％ | ≥75％ | ≥71.2％ |
| F ％ | 23.5-24.8％ | 22.3-25.5％ | 22.3-25.5％ |
| Sb | ≤30 ppm | ≤0.005％ | ≤0.005％ |
| Pb ppm | ≤10 ppm | ≤0.001％ | ≤0.003％ |
| As ppm | ≤1 ppm | ≤0.0003％ | ≤0.0003％ |
| Hg ppm | ≤1 ppm | ≤0.0002％ | ≤0.0002％ |
| Fe ppm | ≤5 ppm | ≤0.001％ | ≤0.0018％ |
| Si ppm | ≤50 ppm | — | — |
| PH（0.4% aqueous solution） | 2.8-3.5 | 2.8-3.5 | 2.8-3.5 |
| Appearance | White crystals | White crystals | White crystals |
| Loss on drying（105℃/4H） ％ | ≤0.2 | ≤0.2 | ≤0.5 |
| Whiteness（70-90ums） ％ | ≥98 | ≥98 | ≥95 |
| Size(U.S.SCREEN) | 90% pass 80-100mesh | 90% pass 80-100mesh | 90% pass 80-100mesh |
| Transmittance(3％aqueous solution) ％ | ≥95 | ≥95 | ≥90 |
| Shelf life | Two years | Two years | Two years |
Tin(II) fluoride main uses
Used in toothpaste production to protect teeth from calcium dissolution or in fluxes for brazing aluminum alloys.
Clinical trials indicate that trace element tin plays a role in remineralization. Stannous fluoride exhibits potent decalcification inhibition, enhancing enamel acid resistance and stability. It shows better efficacy in preventing cavities compared to sodium fluoride. However, stannous fluoride’s drawbacks include a mild unpleasant taste, potential slight extrinsic staining upon topical application, and chemical instability in aqueous solutions.
