is a Japanese multinational electronics corporation that manufactures electronic components and recording and data-storage media. Its motto is "Contribute to culture and industry through creativity". "TDK" is an initialism of the original Japanese name of the company: Tokyo Denki Kagaku Kōgyō K.K. (Tokyo Electric Chemical Industry Co., Ltd.). The company is listed on the Tokyo Stock Exchange and is a constituent of the Nikkei 225 and TOPIX indices. History TDK was founded by Kenzo Saito in Tokyo, Japan, on 7 December 1935 to manufacture the iron-based magnetic material ferrite, which had been recently invented by Yogoro Kato and Takeshi Takei. In 1952 and 1957, they began to produce magnetic tape, with compact cassette tapes following in 1966. TDK manufactured an extensive portfolio of magnetic and optical media, including several formats of videotape and blank CD-R and recordable DVD discs until the recording business was sold to Imation in 2007. TDK produced five million ferrite cores through 1945 that were primarily used to reduce the volume and weight of radio receivers used by the Imperial Japanese military. Operations in the US began in 1965 with a New York City office, and European operations began in 1970 with an office in Frankfurt, West Germany. In 1980, TDK developed a multilayering technology to create chip capacitors and inductors used in personal computers, laptops, smartphones and other electronic devices. In 1986, TDK acquired SAE Magnetics and introduced high-density recording heads. In the 1990s, TDK's Mass Storage Division included brushless DC spindle motors, magnetoresistance (MR) heads and thin-film heads. Since 1997, TDK has gradually withdrawn from the production of compact cassettes. First with the MA-X and AR ("Acoustic Response"), then the AD ("Acoustic Dynamic") and SA-X line in 2001 and 2002 respectively, then the MA ("Metal Alloy") line in 2004. The SA ("Super Avilyn") and D ("Dynamic") lines were withdrawn in 2011. Industry trends see the company moving into new forms of media. In 2004 TDK was the first media manufacturer to join the companies developing BD post-DVD technology. TDK operated a semiconductor division in California for about a decade, but divested it in 2005. In late 2007, Imation acquired marketing and sales operations for TDK brand recording media, including flash media, optical media, magnetic tape, and accessories, for $300 million. This also included a license to use the "TDK Life on Record" brand on data storage and audio products for 25 years. In September