Glittering cube-corner retroreflective sheeting
US5840405A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1996 |
| Grant date | Nov 24, 1998 |
| Priority date | — |
| Expiry date | Apr 30, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24479
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A cube-corner retroreflective sheeting 60 includes an array of cube-corner elements 30 that are defined by three sets of intersecting parallel grooves 45, 46, 47. The cube-corner elements 30 are arranged in the array such that the sheeting 60 glitters when exposed to light. The glitter is in the form of many discreet points of light that tend to blink on and off when viewed by the naked eye. The array may be configured such that a dihedral angle .alpha. varies between adjacent cube faces 31 of adjacent cube-corner elements 30 in each groove in one of the groove sets 45, 46, or 47 and such that base planes are not parallel to each other when the sheeting 60 is laid flat. Preferably, the dihedral angle .alpha. between faces 31 of adjacent cube-corner elements 30 varies in essentially all of the grooves such that the cube-corner elements are randomly tilted throughout the array. The sheeting glitters very well under daytime viewing conditions and also to some extent under nighttime or retroreflective conditions. The glittering effect can enhance the sheeting's conspicuity, and hence highlight a person's presence to give them improved safety and security.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.