Porous calcium phosphate ceramic and method for producing same

• US 20070072009A1
• Filed: 10/27/2004
• Published: 03/29/2007
• Est. Priority Date: 10/27/2003
• Status: Active Grant

• Current Assignee: Hoya Corporation
• Original Assignee: Pentax Corporation (Hoya Corporation)
• Inventors: Matsumoto, Toshio, Nakasu, Masanori
• Granted Patent: US 7,687,138 B2
• Time in Patent Office: Days
• US Class Current: 428/701
• CPC Class Codes: A61C 2008/0046 Textured surface, e.g. roughness, microstructure A61C8/0013 takes precedence
• CPC Class Codes: A61C 8/0012 characterised by the material or composition, e.g. ceramics, surface layer, metal alloy use of specific materials A61K6/00
• CPC Class Codes: A61F 2/0077 Special surfaces of prostheses, e.g. for improving ingrowth A61F2/30767 takes precedence
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2002/30199 Three-dimensional shapes
• CPC Class Codes: A61F 2230/0063 Three-dimensional shapes
• CPC Class Codes: A61F 2310/00293 containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61L 27/12 Phosphorus-containing materials, e.g. apatite
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: C04B 14/366 Phosphates, e.g. apatite
• CPC Class Codes: C04B 20/008 Micro- or nanosized fillers, e.g. micronised fillers with particle size smaller than that of the hydraulic binder colloidal silica C04B14/062 ; silica fume C04B18/146
• CPC Class Codes: C04B 2111/00836 for medical or dental applications
• CPC Class Codes: C04B 2235/3212 Calcium phosphates, e.g. hydroxyapatite
• CPC Class Codes: C04B 26/28 Polysaccharides or derivatives thereof
• CPC Class Codes: C04B 35/447 based on phosphates , e.g. hydroxyapatite
• CPC Class Codes: C04B 38/0003 containing continuous channels, e.g. of the "dead-end" type or obtained by pushing bars in the green ceramic product B28B takes precedence
• CPC Class Codes: C04B 38/0054 the pores being microsized or nanosized
• CPC Class Codes: C04B 38/0074 expressed as porosity percentage
• CPC Class Codes: C04B 38/062 the burned-out substance being formed in situ, e.g. by polymerisation of a prepolymer composition containing ceramic powder
• CPC Class Codes: C04B 40/0268 Heating up to sintering temperatures C04B41/0072 takes precedence
• CPC Class Codes: Y10T 428/249955 : Void-containing component partially impregnated with adjacent component
• CPC Class Codes: Y10T 428/249956 : Void-containing component is inorganic
• CPC Class Codes: Y10T 428/249957 : Inorganic impregnant
• CPC Class Codes: Y10T 428/249967 : Inorganic matrix in void-containing component
• CPC Class Codes: Y10T 428/249979 : Specified thickness of void-containing component [absolute or relative] or numerical cell dimension
• CPC Class Codes: Y10T 428/249981 : Plural void-containing components

Abstract

A porous calcium phosphate ceramic body comprising a substrate 1, and three-dimensional nanotunnel layers 2 formed on wall surfaces of the substrate 1, the three-dimensional nanotunnel layers 2 having pluralities of three-dimensionally connected nanotunnels 21.

Claims

1. A porous calcium phosphate ceramic body comprising a substrate having fine pores, and three-dimensional nanotunnel layers formed on wall surfaces of said fine pores and having pluralities of three-dimensionally connected nanotunnels.

2. The porous calcium phosphate ceramic body according to claim 1, wherein said three-dimensional nanotunnel layers have an average thickness of 20 nm to 10 μ

m.

4. The porous calcium phosphate ceramic body according to claim 1, wherein said three-dimensional nanotunnel layers are formed on 5 to 100% of the wall surfaces of said fine pores.

5. The porous calcium phosphate ceramic body according to claim 1, wherein at least part of said nanotunnels have openings communicating with the fine pores of said substrate.

6. The porous calcium phosphate ceramic body according to claim 5, wherein said openings have an average diameter of 1 to 5000 nm.

7. The porous calcium phosphate ceramic body according to claim 1, wherein said substrate has a porosity of 40 to 98%.

8. The porous calcium phosphate ceramic body according to claim 1, wherein the atomic ratio of Ca/P in said three-dimensional nanotunnel layers is substantially equal to or smaller than that in said substrate.

3. (canceled)

9. A method for producing a porous calcium phosphate ceramic body having a three-dimensional nanotunnels layer, comprising the steps of immersing a porous calcium phosphate substrate in a slurry containing fine calcium phosphate particles, defoaming said slurry under reduced pressure, and heat-treating the slurry-carrying substrate.

10. The method for producing a porous calcium phosphate ceramic body according to claim 9, wherein said fine calcium phosphate particles have an average diameter of 10 nm to 5 μ

m.

11. The method for producing a porous calcium phosphate ceramic body according to claim 10, wherein said fine calcium phosphate particles are as long as 10 to 200 nm in the c-axis and 1 to 100 nm in the a-axis, and have a specific surface area of 30 to 300 m²/g.

12. The method for producing a porous calcium phosphate ceramic body according to claim 10, wherein said fine calcium phosphate particles are single crystals of calcium phosphate.

14. The method for producing a porous calcium phosphate ceramic body according to claim 9, wherein said heat treatment is conducted at a temperature of 600 to 900°

C.

13. (canceled)