Microcapsules for magnetic display and magnetic display sheet comprising such microcapsules
US5972493A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1995 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Aug 8, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/28
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
Gelatin microcapsules for magnetic display enclosing therein dispersion medium, magnetic powder and nonmagnetic powder, characterized in that that the dispersion medium in the microcapsules is composed of at least low boiling point solvent, particle diameter of the microcapsules is ion a range of 400 .mu.m tap 800 .mu.m and particles bigger than average are removed out. And solvents with boiling point higher than 175 .degree. C., dispersant and suspension are contained in the dispersion medium, magnetic powder and nonmagnetic powder are affinity-treated. The microcapsule magnetic display sheet is produced by coating the above-described microcapsules. Therefore, recording speed and erasing speed are fast and recorded words or pictures are clear even if a magnetic force lower than 1100 gauss is used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.