Devices for producing optical effect layers
US10391519B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 28, 2014 |
| Grant date | Aug 27, 2019 |
| Priority date | — |
| Expiry date | Aug 10, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F41/16
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
The present invention relates to the field of the protection of value documents and value commercial goods. In particular, the invention relates to methods of making an optical effect layer (OEL) associated with a substrate, the method comprising i) providing a substrate associated with a coating composition comprising magnetic or magnetizable pigment particles; ii) providing a permanent magnet assembly producing a first magnetic field; iii) providing an electromagnet assembly including a winding assembly and drive producing an oscillating or rotating second magnetic field that interacts with the first magnetic field to spin the permanent magnet assembly to rotate the first magnetic field; and iv) applying the first magnetic field while the first magnetic field rotates by spinning of the permanent magnet assembly to aggregately orient the magnetic or magnetizable pigment particles to create the optical effect layer. The invention also relates to apparatuses for creating an OEL.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.