公开(公告)号：EP3783398A1

公开(公告)日：2021-02-24

申请号：EP20201739.8

申请日：2015-05-13

Applicant: Toppan Printing Co., Ltd.

Inventor： Ide, Hidetaka

IPC: G02B5/18 ,  G03H1/02 ,  B42D25/328 ,  B42D25/40 ,  G03H1/00 ,  G03H1/26 ,  B42D25/324 ,  B42D25/47

Abstract: Provided are diffraction structure transfer foil that further improves usefulness of the diffraction structure transfer foil in authenticity determination by allowing a greater variety of diffracted-light patterns to be observed, and a forgery prevention medium using the diffraction structure transfer foil. The diffraction structure transfer foil (21) includes a transfer foil substrate (1), a peeling-off protective layer (2) that is laminated on one surface of the transfer foil substrate (1), a laminated body for diffracted-light delivery (13a) that is laminated on the peeling-off protective layer (2), and an adhesive layer (9) that is laminated on the laminated body for diffracted-light delivery (13a). The laminated body for diffracted-light delivery (13a) includes a diffraction structure forming body in which a plurality of diffraction structures (4 and 7) are formed, and a reflective layer (5a or 8a) that is formed in accordance with each of the plurality of diffraction structures (4 and 7). A transmission density of one reflective layer (5a) of the plurality of reflective layers (5a and 8a) is in a range of 0.01 to 0.9, and a transmission density of the other reflective layer (8a) is 1.0 or greater.

公开(公告)号：EP3851291A1

公开(公告)日：2021-07-21

申请号：EP21161980.4

申请日：2018-05-25

Applicant: Toppan Printing Co., Ltd.

Inventor： Ide, Hidetaka ,  Minamikawa, Naoki

IPC: B42D25/328 ,  B42D25/435 ,  G02B5/18 ,  G09F3/02 ,  B42D25/324

Abstract: An information recording medium (10a) formed by laminating a transparent protective layer (40) and a base material (20) having laser color-developing properties is provided. The information recording medium (10a) includes an intermediate layer (30) that is disposed between the transparent protective layer (40) and the base material (20). In the information recording medium (10a), the intermediate layer (30) includes a diffraction structure layer (32) that has a diffraction structure, and a first reflective layer (36) that reflects visible light and is destroyed when irradiated with a laser beam. Light, when incident from a transparent protective layer (40) side, causes a diffracted light pattern to appear in the diffraction structure layer (32) so as to be observable from the transparent protective layer (40) side. A laser beam, when applied from the transparent protective layer (40) side, passes through the diffraction structure layer (32), destroys the first reflective layer (36), and develops color in the base material (20).