| 1940 | 
            Mar. | 
            Koa Kogyo-sya is established by Kazuto Mukaiyama in Tokyo to manufacture fixed resistors. | 
        
        
            | 1941 | 
            Dec. | 
            Establishes Ina Factory (at the location of the present registered office) in Ina, Nagano to expand its manufacturing capacity. | 
        
        
            | 1942 | 
            Jul. | 
            Begins production of capacitors. | 
        
        
            | 1943 | 
            Oct. | 
            Establishes Nagoya Local Office. | 
        
        
            | 1944 | 
            May | 
            Gets certified as a Labor-Relations-Adjustment-Act (Article 2) applicable factory. | 
        
        
            | 1946 | 
            Apr. | 
            Establishes a corporate logo. | 
        
        
            | 1947 | 
            May | 
            Gets certified as a key factory for telecommunication sector by the Commercial and Industrial Office. | 
        
        
            | May | 
            Becomes a joint-stock corporation. [Capital: 0.8M JPY] | 
        
        
            | Jun. | 
            Establishes Tokyo Office and Nagoya Office. | 
        
        
            | 1948 | 
            Sep. | 
            Increases the capital. (fully paid-up) [Capital: 1.6M JPY] | 
        
        
            | 1950 | 
            Nov. | 
            Closes Nagoya Office. | 
        
        
            | Nov. | 
            Establishes Kansai Office in Osaka. | 
        
        
            | Dec. | 
            Changes its name to KOA DENKO Co., Ltd. | 
        
        
            | 1953 | 
            Nov. | 
            Increases the capital. (fully paid-up) [Capital: 2.6M JPY] | 
        
        
            | 1955 | 
            Jun. | 
            Becomes a Japanese Industrial Standards (JIS) authorized manufacturer. | 
        
        
            | Jul. | 
            Establishes Kanda Sales Office in Tokyo. | 
        
        
            | 1956 | 
            Mar. | 
            Increases the capital. (fully paid-up)  [Capital: 4.8M JPY] | 
        
        
            | Dec. | 
            Receives an award for being an excellent factory by the Minister of Health, Labour and Welfare. | 
        
        
            | 1957 | 
            Feb. | 
            Increases the capital. (fully paid-up)  [Capital: 9.6M JPY] | 
        
        
            | 1958 | 
            Apr. | 
            Establishes Minowa Factory in Minowa-machi, Kamiina-gun, Nagano. | 
        
        
            | 1959 | 
            Feb. | 
            Establishes Kawasaki Office in Kawasaki-shi. | 
        
        
            | Jul. | 
            Increases the capital. (fully paid-up)  [Capital: 19.2M JPY] | 
        
        
            | Nov. | 
            Becomes a NDS XXC6442 (Japan Defense Agency Standard) authorized manufacturer of fixed film resistors. |