Organic phosphorous compound, a process for producing the same and a use thereof

An organic phosphorous compound represented by the following formula (I):

• ##STR6## wherein R.sup.1, R.sup.2, R.sup.5 and R.sup.6 independently represent a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms or a phenyl group;
• R.sup.3 represents a hydrogen atomor an alkyl group having 1 to 8 carbon atoms;
• R.sup.4 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms or a phenyl group, or the two R.sup.4 may be combined with each other to form a direct bond, a sulfur bond (--S--), or a methylene group which is optionally substituted with alkyl having 1 to 8 carbon atoms or cycloalkyl having 5 to 8 carbon atoms;
• R.sup.7 and R.sup.8 independently represent a hydrogen atom or an aikyl group having 1 to 8 carbon atoms, or R.sup.7 and R.sup.8 may be combined with each other to form an alkylene group having 2 to 4 carbon atoms;
• A represents an alkylene group having 2 to 8 carbon atoms;
• B represents a direct bond or an alkylene group having 1 to 8 carbon atoms;
• and one of Y and Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms or an aralkyloxy group having 7 to 12 carbon atoms, and the other one represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.