| 摘要 |
<p>A card of redeemable value (2) is disclosed which is printed with secure information (6) which must be viewed to redeem the value of the card (2), the secure information (6) being typically in the form of alphanumeric characters covered by a scratch off material (10). The scratch off layer (10) is then subjected to a subsequent treatment process wherein portions of the scratch off layer (10) are treated (12) and portions remain untreated to provide the treated portions with a visibly different appearance from the untreated portions. The treated portions are arranged in a pattern which may be in the form of text or meandering lines and prevent compromise of the card by pressured application of adhesive tape to remove the scratch off (10) because during the pressured application of tape of the scratch off (10), the appearance of the treated portions and untreated portions of the card is rendered identical as the tape effectively standardises the gloss levels of the treated and untreated portions. Accordingly, after pressured application of the adhesive tape, the pattern over the scratch off resulting from the treatment of certain portions disappears and a retailer can easily identify that the card has been compromised.</p> |
