A well-designed seal case protects a seal from damage or loss, makes carrying and transporting a seal safe and easy, and is an elegant accessory.
- July 1, 2022
- The latest catalog is completed.
Koseido Case Catalog vol.2
New products and "Prime Series" are also posted.
- December 16, 2021
- Notice of new product sales
From December 22, 2021, two products, "Piano" and "New Ryukyu", will be on sale.
Please take a look at this opportunity.
- January 16, 2021
- New Prime Series launched
- December 1, 2020
- Upcoming Prime Series featured in the December edition of The Journal of All Stamping & Seals
- June 30, 2020
- Utility model rights obtained for purse-shaped seal case
I am the third-generation Representative Director of Koseido, which originated in 1947 as the Kasai Koseido Metal Frame Shop specializing in making metal-frame cases for the seal stamps that are commonly used in place of signatures in Japan. Prior to joining Koseido, after college I worked for two years in the manufacturing department of a food company where I gained invaluable experience in manufacturing technology and services. When I became Representative Director in 2016, I brought this experience to a company with a tradition of high-level craftsmanship and success . We at Koseido remain dedicated to our original commitment to craftsmanship that creates satisfied customers and gratified employees.
|Hiroki Kasai establishes Kasai Koseido Metal Frame Shop and begins manufacture of metal frames for seal cases in Nishijima, Minobu City, Minamikoma District, Yamanashi Prefecture
|Sakae Kasai becomes head of the company and expands the variety of seal cases offerings
|New factory constructed
|Sakae Kasai incorporates the company as Koseido Ltd. and becomes Representative Director
|Utility model rights obtained for a unique rounding process for metal frame hinges, increasing frame safety
|Eiki Kasai becomes Representative Director
|Utility model rights obtained for a purse-shaped seal case
|Prime Series launched
|Koseido Company Limited
|5 million yen
|Nishijima 1814-1 Minobu City, Minamikoma
|Yamanashi Prefecture 409-3301 Japan
|The Yamanashi Chuo Bank, Ltd.
|Manufacture and sale of metal frames seal cases
Nishijima 1814 -1 Minobu City, Minamikoma District, Yamanashi Prefecture 409-3301 Japan