Abstract: The invention provides a process by which rare earth metal ions can be efficiently extracted by easy operation, and effective extracting reagents for the process. Specifically, phosphonamides represented by the general formula [1]; a process for producing the same; reagents for extracting rare earth metal ions, containing the phosphonamides; and a process for extraction of rare earth metal ions with the phosphonamides: [1] wherein R1 is alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, aryl, aralkyl, or a heterocyclic group, with the proviso that each group may be substituted; R2 is hydrogen, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, aralkyl, or a heterocyclic group, with the proviso that each group may be substituted; R3 is hydrogen, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, aralkyl, or a heterocyclic group, with the proviso that each group may be substituted, or the two R3s may be united to form alkylene, cycloalkylene, or arylene.

Abstract: The present invention provides a resin composition which can be cured by visible light and whose cured product is not colored or little colored, said composition comprising a phosphine oxide compound represented by the following general formula (1) (wherein R1 represents alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted aralkyl, or substituted or unsubstituted aralkenyl; and R2, R3, R4, R5, R6, R7, R8 and R9, which may be the same or different, each represent a hydrogen atom, a halogen atom, alkyl, alkenyl, substituted or unsubstituted aralkyl, or substituted or unsubstituted aralkenyl, and two adjacent groups among R2, R3, R4, R5, R6, R7, R8 and R9 may form a hydrocarbon ring together with the two carbon atoms adjacent thereto) and an unsaturated compound.

Abstract: An electroluminescent device comprising electrodes consisting of a pair of an anode and a cathode, at least one of the electrodes being either transparent or translucent, and an organic layer interposed between said electrodes, wherein said organic layer comprises a copolymer comprising in the main chain thereof 9-oxo-9-phosphafluorene-2,7-diyl units and arylene units, represented by formula (1) below, and the thickness of said organic layer is from 1 nm to 10 ?m: wherein R represents hydrogen, alkyl, cycloalkyl, aralkyl, aryl, alkyloxy, cycloalkyloxy, aralkyloxy, or aryloxy; Ar represents arylene; and n is an integer of 3 to 30,000.

Abstract: A polymer containing in the backbone a 9-oxo-9-phosphafluorene-2,7-diyl skeleton or a combination of the skeleton with a vinylene skeleton or arylene skeleton. The polymer is utilizable as, e.g., a component of a luminescent element or electrochromic element. The polymer is obtained by subjecting a 2,7-dihalo-9-oxo-9-phosphafluorene to polycondensation with dehalogenation, or to reaction with arylenebisboronic acid and polycondensation, or to polycondensation with an olefin.

Abstract: The invention provides a process by which rare earth metal ions can be efficiently extracted by easy operation, and effective extracting reagents for the process. Specifically, phosphonamides represented by the general formula [1]; a process for producing the same; reagents for extracting rare earth metal ions, containing the phosphonamides; and a process for extraction of rare earth metal ions with the phosphonamides: [1] wherein R1 is alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, aryl, aralkyl, or a heterocyclic group, with the proviso that each group may be substituted; R2 is hydrogen, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, aralkyl, or a heterocyclic group, with the proviso that each group may be substituted; R3 is hydrogen, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, aralkyl, or a heterocyclic group, with the proviso that each group may be substituted, or the two R3s may be united to form alkylene, cycloalkylene, or arylene.

Abstract: An electroluminescent device comprising electrodes consisting of a pair of an anode and a cathode, at least one of the electrodes being either transparent or translucent, and an organic layer interposed between said electrodes, wherein said organic layer comprises a copolymer comprising in the main chain thereof 9-oxo-9-phosphafluorene-2,7-diyl units and arylene units, represented by formula (1) below, and the thickness of said organic layer is from 1 nm to 10 ?m: wherein R represents hydrogen, alkyl, cycloalkyl, aralkyl, aryl, alkyloxy, cycloalkyloxy, aralkyloxy, or aryloxy; Ar represents arylene; and n is an integer of 3 to 30,000.

Abstract: A polymer containing in the backbone a 9-oxo-9-phosphafluorene-2,7-diyl skeleton or a combination of the skeleton with a vinylene skeleton or arylene skeleton. The polymer is utilizable as, e.g., a component of a luminescent element or electrochromic element.