| 摘要 |
A security device is integrally combined with the fibres of the paper in a paper-making process. A carrier web of water-dispersible fibres carrying the security element is brought into contact with the paper stock during the paper-making process. The carrier web becomes rapidly dispersed upon contact with the wet stock leaving the security element firmly attached to the paper fibres in the stock. In one embodiment, the security element comprises a plastic diffraction grating structure. In a further embodiment, the carrier web comprises an open porous structure for enhancing intermixing with the paper stock.
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