| 摘要 |
PURPOSE: To prevent counterfeiting of sale record comprising alphanumeric characters by printing different parts of at least some of the characters making up the record in a plurality of colors. CONSTITUTION: A dot matrix printer can be modified easily by fixing a ribbon which can be split into more than one different colors in the longitudinal direction, i.e., the advancing direction, in place of an ordinary monochromatic print ribbon. The split ribbon can be arranged such that upper half of a character is printed in one color and the lower half is printed in a different color. The ribbon may have two bands of similar color separated by a third band of different color, as the case may be. In one sales record, at least several alphabet characters may be printed partially in one color and several other alphabet characters may be printed partially in other color. Additionally, means is provided for making counterfeiting difficult furthermore by inverting the direction of the color band on a second path from that on a first path. |
