Patent ID: 7169372

Claim:
A method for producing hydroxyapatite particles, involving an interaction of a calcium hydroxide suspension with phosphoric acid in a stoichiometric ratio, comprising the steps of a) mixing and homogenizing a suspension comprising calcium hydroxide with an amount of phosphoric acid within a first reactor thereby adjusting a defined alkaline pH-value of the resulting mixture b) feeding the mixture into a second reactor for causing phase transformations of the mixture, c) feeding the mixture into a third reactor for providing a suspension by adding a suspension of calcium hydroxide to the mixture to then feed the suspension into the first reactor, wherein the holding time in the first stage is 0.2 s to 0.8 s and wherein each of the steps a), b), c) is cyclically carried out in continuous periodical conditions within at least three stages thereby producing nano-sized crystalline particles of pure hydroxyapatite as a solid phase.