Method of producing fluorapatite and a moisture sensitive resistor using fluorapatite obtained by the same
US4971739A · kind A · utility
10Cited by
2References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 12, 1989 |
| Grant date | Nov 20, 1990 |
| Priority date | — |
| Expiry date | Apr 12, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/121
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of producing fluorapatite wherein predetermined amounts of calcium monohydrogen phosphate, calcium carbonate, and calcium fluoride are weighed, subjected to a mechanochemical action, and caused to react with one another in water. With this method, a fluorapatite having a uniform composition can be obtained without the accompaniment of by-products. A moisture sensitive resistor of the present invention can be obtained by sintering the fluorapatite produced in accordance with this method. This moisture sensitive resistor has a sufficiently low resistance corresponding to a humidity, and has substantially no hysteresis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.