PROBLEM TO BE SOLVED: To suppress generation of byproducts so as to improve production efficiency and purification efficiency of an N-(iodophenyl)pyrimidinylamine derivative, when producing the N-(iodophenyl)pyrimidinylamine derivative.

PROBLEM TO BE SOLVED: To provide a flame retardant film having superior coloring processability and fire retardancy, and to provide a processed product using the film.

PROBLEM TO BE SOLVED: To provide a phosphor paste hardly catching bubbles into a cell when applied to a PDP, and capable of preventing the application from being left out.

PROBLEM TO BE SOLVED: To provide lactic acid suitable for producing polylactic acid excellent in property balance among thermal stability, mechanical strength and hues by a direct dehydrative condensation reaction of lactic acid.

PROBLEM TO BE SOLVED: To readily produce 5-aminolevulinic acid in high yield by using an inexpensively available raw material. ; SOLUTION: The new method for producing the 5-aminolevulinic acid comprises reacting succinic anhydride with a metal prussiate to synthesize 4-cyano-4-oxolevulinic acid or a metal salt thereof, and reducing the obtained 4-cyano-4-oxolevulinic acid by a reducing method such as a catalytic hydrogenation method. The synthesizing method gives higher yield and higher efficie...