Tatsuo Yoshii

Title: Tatsuo Yoshii and Steel for Color CRT Mask Frames.

Introduction

Tatsuo Yoshii is an inventor associated with Wakayama, Japan. His work includes inventions concerning steel sheets and mask frames for color cathode-ray tubes (CRTs). The supplied information credits him with 2 patents.

Latest Patents

Yoshii’s listed patents focus on materials and manufacturing methods for color CRT mask frames.

- **Color CRT mask frame, a steel sheet used therefor and a manufacturing method for the steel sheet, and a color CRT equipped with the frame.** This invention describes a mask frame made from a specified steel composition, with controlled ferrite grain size and volume ratio. The composition includes carbon, manganese, molybdenum, vanadium, and nitrogen, with limits on other elements and a balance of iron and unavoidable impurities. The stated structure has ferrite grains no larger than 15 micrometers and a ferrite volume ratio no greater than 90%.

- **Steel sheet used for color CRT mask frame and a manufacturing method for the steel sheet.** This invention concerns steel sheet for a frame that holds a tension-type color CRT shadow mask under tension. It specifies a steel composition and microstructure, and describes manufacturing the sheet by hot-rolling a slab at a finishing temperature of 820–950°C and a coiling temperature of 400–700°C.

Career Highlights

The available information identifies Yoshii’s patent work in steel materials and manufacturing processes for CRT components. The supplied company field is “Other,” so no company is listed here.

Collaborations

Noriaki Nagao and Shinji Tsuge are identified as Yoshii’s coworkers in the supplied information.

Conclusion

Tatsuo Yoshii’s listed inventions address the composition, structure, and production of steel sheets used in color CRT mask frames.