Abstract
Hydroxyapatite(HAp) coating using HAp particles including alkoxysilyl group(s) was developed as a novel method for the introduction of HAp on metal substrates. The derivatives of HAp having alkoxysilyl group(s) were synthesized by the reaction of HAp particles with various isocyanates in DMF, followed by addition of monoalkoxysilane or bis (alkoxysilane). In these derivatives of HAp, the alkoxysilyl group(s) was/were hydrolyzed in ethanol with water and acetic acid to prepare the precursor suspension solutions. The titanium plate or the stainless steel (SUS316L) plate, which was dip-coated using these suspension solutions, was heat-treated at 200°C. The coated metal surfaces were observed by microscope and SEM. As a result, it was found that the metal surfaces were coated by HAp most effectively when the HAp-urethane-urea derivative having the urea linkage in the molecule, which was synthesized from 1,3-bis (isocyanatomethyl) cyclohexane, was used in the coating. The peeling test of this HAp coating indicated that the most of the coated HAp particles remained on the metal surfaces.
