Preparation of an inorganic substrate having antimicrobial properties

A process for modifying an inorganic substrate, directed toward giving it antimicrobial properties, said process comprising grafting in one or more steps onto a surface of said substrate groups with intrinsic antimicrobial properties or groups capable of releasing species with antimicrobial properties, the grafting being performed by means of an organophosphorus coupling agent, wherein the organophosphorus coupling agent is selected from the group consisting of phosphonic acids and phosphonates of formula RPO(OX)2, bis-phosphonates of formula RR′[PO(OX)2]2, the phosphinic acids and phosphinates of formula RR′PO(OX), monoalkyl phosphates of formula ROPO(OX)2, and the dialkyl phosphates of formula (RO)(R′O)PO(OX), in which:

• X represents a hydrogen atom or a group selected from the group consisting of metal ions, ammonium ions, alkyl or aryl groups containing from 1 to 6 carbon atoms and trialkylsilyl groups containing from 1 to 6 carbon atoms;
• R is an organic group selected from the group consisting of:
• groups with intrinsic antimicrobial properties;
• groups that are capable of releasing species with antimicrobial properties, selected from the group consisting of groups that release nitrogen monoxide and groups that release carboxylic acids;
• groups R″ which, after modification, have intrinsic antimicrobial properties or are capable of releasing species with antimicrobial properties, said groups R″ being selected from the group consisting of
• groups —(CH2)n—SH, —(CH2)n—CN, —(CH2)n—NH2, —(CH2)n—[NH—(CH2)n′]n″—NH2, —(CH2)n—NMe2, —(CH2)n—Hal, Hal representing a halogen atom n being between 1 and 20, n′ being between 1 and 5 and n″ being between 1 and 10;
• R′ is a hydrogen atom, a hydroxyl group or an organic group corresponding to the definition given for the groups R.