IDENTIFYING MEDIUM AND IDENTIFYING METHOD FOR OBJECT

Title:

IDENTIFYING MEDIUM AND IDENTIFYING METHOD FOR OBJECT

Document Type and Number:

WIPO Patent Application WO/2003/069587

Kind Code:

A1

Abstract:

An identifying medium (A) for identifying the authenticity of an object by providing an optically identifiable mark on the object. A film (20) having the light reflection layer of polymer cholesteric liquid crystal having in turn a circularly polarized light selectivity of reflecting a specific circular polarized light is fixed to part of the surface of a support (10), and printing is made on the portions other than the film (20) of the support (10) in the same color as that shown when the film (20) is viewed from the front. The identifying medium (A) appears to be red at the support (10) and the film (20) when viewed from the front (although the film has a metallic gloss), but, at a larger viewing angle, the film (20) changes to blue by the blue-shift of polymer cholesteric liquid crystal to show a color different from the support (10) does.

Inventors:

HOSHINO HIDEKAZU (JP)
TAKEUCHI ITSUO (JP)
SASAKI MUTSUMI (JP)

Application Number:

PCT/JP2003/001431

Publication Date:

August 21, 2003

Filing Date:

February 12, 2003

Export Citation:

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Assignee:

NHK SPRING CO LTD (JP)
HOSHINO HIDEKAZU (JP)
TAKEUCHI ITSUO (JP)
SASAKI MUTSUMI (JP)

International Classes:

B42D15/10; B44F1/12; B65D55/02; G02B5/30; G02F1/13; G07D7/12; G09F3/00; (IPC1-7): G09F3/03; G09F19/12; G07D7/12; B42D15/10

Foreign References:

DE3942663A1	1991-06-27
JP2000318399A	2000-11-21
JP2001133566A	2001-05-18
JP2001141577A	2001-05-25
JPH08115051A	1996-05-07
EP0911758A2	1999-04-28
EP1028359A1	2000-08-16
EP1028359A1	2000-08-16
DE3942663A1	1991-06-27
JP2000318399A	2000-11-21
JPH04144796A	1992-05-19
JPS6351193A	1988-03-04
JPS57165480A	1982-10-12
JPS5817119A	1983-02-01

Other References: