| abstract |
15838abs ABSTRACT A composition of matter which comprises a solid substrate having covalent bonds to at least one member selected from sub-groups (a) and (b), namely: (a) substantially a single layer of at least one species of microspheres containing residual reactive functions; (b) a multiplicity of layers of at least one species of microspheres, wherein adjoining layers of the multiplicity of layers are covalently linked together, the innermost layer of the multiplicity of layers having the above-mentioned covalent bonds to the solid substrate connected thereto, while at least the outermost layer of the multiplicity of layers contains residual reactive functions. |