Yokoisada Co., Ltd.

Yokoisada Co., Ltd. (横井定株式会社) is a Japanese mask manufacturer headquartered in Mizuho-ku, Nagoya, Aichi Prefecture. Founded in April 1950 by Sadao Yokoi as a sole proprietorship, the company began selling general-purpose masks under the name "Nippon Mask" around 1954 and was incorporated in February 1958 as Yokoi Sadao Shoten Co., Ltd. It relocated to its current address and changed its name to Yokoisada Co., Ltd. in February 1971. The company registered "Nippon Mask®" as a trademark in April 1995, a registration it regards as unusual for combining a country name with a generic term, attributing it to its long contribution to creating Japan's mask market. The company describes itself as a specialist mask manufacturer that has produced and sold masks for more than half a century under the Nippon Mask® brand. Its strength lies in integrated planning and production, with fully automated machines that minimize human contact from production through finished mask, low defect rates, hygienic and stable output, and cleanroom production management. This history and reliability underpin its OEM business, which covers novelty masks, private-label masks for drugstores, character masks, original face-shaped facial masks, proposals for new nonwoven fabrics, and original-print 3D eye masks. Yokoisada's product range spans general-use masks (gauze masks and nonwoven masks), nonwoven aprons, and beauty facial masks, as well as character masks featuring properties such as Rilakkuma, Moomin, Miffy, Chiikawa, Snoopy, Pokémon and others, 3D masks, box masks, kids' masks, disposable head caps, eye masks and other lifestyle items. Its manufacturing footprint includes a headquarters in Nagoya, a factory in Nantong, China (Nantong Xin Sanxi Yokoisada Hygiene Materials Co., Ltd.) and a factory in Clark, Philippines (YOKOISADA (PHILS.) CORPORATION). The company holds CE marking conformity, FDA, ISO13485 and Disney FAMA certifications. It is a private company with stated capital of 10 million yen, led by President Yuki Yokoi as of September 2026, and is an official sponsor of the Japan Curling Association.

Yokoisada Co., Ltd. traces its origins to April 1950, when Sadao Yokoi began a sole proprietorship in Idota-cho, Mizuho-ku, Nagoya. Around 1954, the business began selling general-purpose masks under the name "Nippon Mask." In February 1958, it relocated to Sozaku-cho, Mizuho-ku, Nagoya, and was incorporated as Yokoi Sadao Shoten Co., Ltd. In February 1971, the company moved to its current location in Kagitacho and changed its name to Yokoisada Co., Ltd. In April 1995, it registered "Nippon Mask®" as a trademark; the company has stated that registration of a trademark combining a country name with a generic term is rare and reflects its significant contribution to establishing Japan's mask market. In July 1996, the company established a local subsidiary in Nantong, Jiangsu Province, China, named Nantong Sanxi Yokoisada Hygiene Materials Co., Ltd. In May 1999, it built the West Building adjacent to its headquarters. In July 2006, Akira Yokoi became Representative Director. In July 2009, the Nantong subsidiary underwent a full renovation, followed in May 2010 by renovation and expansion of its nonwoven production equipment. In September 2011, the headquarters facilities were renovated. In October 2013, the company established YOKOISADA (PHILS.) CORPORATION in Clark, Pampanga, Philippines. In January 2015, the Philippine facilities were expanded; in September 2015, the Chinese factory was relocated and the local subsidiary renamed Nantong Xin Sanxi Yokoisada Hygiene Materials Co., Ltd. In June 2018, the company began selling "VR GOGGLID," a disposable cover for VR head-mounted displays. In September 2018, it introduced beauty mask production equipment at YOKOISADA (PHILS.) CORPORATION. In December 2018, it launched nonwoven masks featuring Winnie the Pooh and Snoopy, manufactured in the Philippines. In 2019, it released a series of character masks (Rilakkuma, Miffy, Barbapapa) and functional masks, all manufactured in the Philippines, and relocated the Philippine corporation in September. In April 2020, responding to mask shortages during the COVID-19 pandemic, it announced a production increase plan for the Philippine Clark factory, aiming for a monthly capacity of 2 million masks. Around April 11, 2020, phishing emails impersonating the Nippon Mask online shop were reported; the company does not distribute such newsletters, and the emails were believed to be aimed at stealing addresses and credit card information. In March 2023, the company introduced an AI image inspection system. In July 2023, YOKOISADA (PHILS.) CORPORATION obtained ISO13485 certification for medical device quality management systems, and in October 2023 it obtained local FDA certification. In September 2026, Yuki Yokoi became Representative Director. The company holds CE marking conformity, FDA, ISO13485 and Disney FAMA certifications, and is an official sponsor of the Japan Curling Association.

• Sadao Yokoi begins sole proprietorship in Idota-cho, Mizuho-ku, Nagoya

• Begins selling general-purpose masks under the name "Nippon Mask"

• Incorporated as Yokoi Sadao Shoten Co., Ltd. in Sozaku-cho, Mizuho-ku, Nagoya

• Relocates to current address and changes name to Yokoisada Co., Ltd.

• Registers "Nippon Mask®" as a trademark

• Establishes Nantong Sanxi Yokoisada Hygiene Materials Co., Ltd. in Nantong, China

• Builds West Building adjacent to headquarters

• Akira Yokoi becomes Representative Director

• Full renovation of Nantong Sanxi Yokoisada Hygiene Materials Co., Ltd.

• Renovation and expansion of nonwoven production equipment at Nantong subsidiary

• Headquarters facilities renovated

• Establishes YOKOISADA (PHILS.) CORPORATION in Clark, Pampanga, Philippines

• Expands YOKOISADA (PHILS.) CORPORATION facilities

• Relocates Chinese factory and renames local subsidiary to Nantong Xin Sanxi Yokoisada Hygiene Materials Co., Ltd.

• Launches "VR GOGGLID" disposable cover for VR head-mounted displays

• Introduces beauty mask production equipment at YOKOISADA (PHILS.) CORPORATION

• Launches nonwoven masks featuring Winnie the Pooh and Snoopy

• Launches Rilakkuma nonwoven masks and functional masks

• Launches Miffy nonwoven masks

• Launches Barbapapa nonwoven masks

• Announces Philippine Clark factory production increase plan to 2 million masks per month

• Introduces AI image inspection system

• YOKOISADA (PHILS.) CORPORATION obtains ISO13485 certification

• YOKOISADA (PHILS.) CORPORATION obtains local FDA certification

Long-established specialist mask manufacturer offering integrated planning-to-production, high quality, small-lot flexibility and OEM services.

• Nippon Mask® general-use masks

  Gauze and nonwoven masks for general use

• Character 3D masks

  Masks featuring characters such as Rilakkuma, Moomin, Miffy, Chiikawa, Snoopy, Pokémon

• Hitomi no Kyusoku 3D eye masks

  Foldable 3D nonwoven eye masks, 3mm thin, with pouch

• VR GOGGLID

  Disposable cover for VR head-mounted displays

• Disposable head caps

  Nonwoven head caps for business use

• Beauty facial masks

  Facial masks for beauty use

1. 1横井定株式会社 - 日本マスク® 公式サイトnippon-mask.co.jp
2. 2企業情報 | 横井定株式会社 - 日本マスク®nippon-mask.co.jp
3. 3商品紹介 | 横井定株式会社 - 日本マスク®nippon-mask.co.jp
4. 4ひとみの休息 ちいかわ 3D アイマスク セット | 横井定株式会社 - 日本マスク®nippon-mask.co.jp
5. 5横井定 - Wikipediaja.wikipedia.org
6. 6Yokoisada - Wikidatawikidata.org