TDK

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Since 1997, TDK has gradually withdrawn from the production of compact cassettes.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 The SA ("Super Avilyn") and D ("Dynamic") lines were withdrawn in 2011.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.
The company dabbled into the video game business in the late 1990s and early 2000s, by operating TDK Mediactive in the U.S. and Europe, and TDK Core in Japan.

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 2015, Imation announced that it had agreed to relinquish this license and would cease selling TDK-branded products by the end of the year.

https://en.wikipedia.org/wiki/TDK