Encapsulated magnetic pigments, processes for their preparation and their uses
US6187439A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 4, 1994 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | Nov 4, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2998
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Encapsulated particles, such as magnetic particles, colored pigments, or carbon black, with high chemical affinity for ink vehicles. The encapsulated particles of this invention are suitable for printing inks, as well as for magnetic recording systems, such as audio and video tapes and magnetic storage disks, when the encapsulated particles are magnetic particles. The encapsulated particles comprise particles having a coating on their surface, said coating comprising in one embodiment an ionomer and in another embodiment, an oil, such as soya oil, and optionally a thixotropic agent, and/or a binder resin. The method of the present invention for making such encapsulated particles avoids the use of volatile organic solvents and provides printing inks and coating compositions comprising such encapsulated particles, that also avoid the use of volatile organic solvents. Inks may be readily formulated without the need for the complicated and expensive flushing process, by simply dispersing the encapsulated colored pigment or carbon black in the desired vehicle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.