A redundantly printed security-enhanced document, printing method and system ensure the meaning of the information imparted by variable indicia printed by redundant printing on the document with removable scratch-off coatings. By printing the variable indicia with multiple colors, redundancy and integrity of the intended indicia is achieved. Additionally, inverted color indicia countermeasures to pinprick attacks are also disclosed. The redundantly printed document, methods and systems enhance the overall appearance of the redundantly printed document, and reduce possible consequences resulting from misprinted variable indicia. The resultant printed process color indicia maintains a grayscale equivalent level of a process color greater than or equal to the measured grayscale equivalent level of the substrate surface plus an additional contrast delta of 15%.

In a first image formation mode, an image is formed with a first development contrast C1 and a specific dot pattern is formed with a second development contrast C2, which is lower than the first development contrast C1; in a second image formation mode, an image is formed with a third development contrast C3 and a specific dot pattern is formed with a fourth development contrast C4, which is lower than the third development contrast C3; and when ΔC1 (=C2/C1) denotes a ratio between the second development contrast C2 and the first development contrast C1, and ΔC2 (=C4/C3) denotes a ratio between the fourth development contrast C4 and the third development contrast C3, ΔC2<ΔC1 is satisfied.

A redundantly printed security-enhanced document, printing method and system ensure the meaning of the information imparted by variable indicia printed by redundant printing on the document with removable scratch-off coatings. By printing the variable indicia with multiple colors, redundancy and integrity of the intended indicia is achieved. Additionally, inverted color indicia countermeasures to pinprick attacks are also disclosed. The redundantly printed document, methods and systems enhance the overall appearance of the redundantly printed document, and reduce possible consequences resulting from misprinted variable indicia. The resultant printed process color indicia maintains a grayscale equivalent level of a process color greater than or equal to the measured grayscale equivalent level of the substrate surface plus an additional contrast delta of 15%.

A redundantly printed security-enhanced document, printing method and system ensure the meaning of the information imparted by variable indicia printed by redundant printing on the document with removable scratch-off coatings. By printing the variable indicia with multiple colors, redundancy and integrity of the intended indicia is achieved. Additionally, inverted color indicia countermeasures to pinprick attacks are also disclosed. The redundantly printed document, methods and systems enhance the overall appearance of the redundantly printed document, and reduce possible consequences resulting from misprinted variable indicia. The resultant printed process color indicia maintains a grayscale equivalent level of a process color greater than or equal to the measured grayscale equivalent level of the substrate surface plus an additional contrast delta of 15%.

An optical article printed on a substrate may include an organic binder; and a plurality of reflective magnetic platelets provided in the organic binder, wherein the plurality of reflective magnetic platelets are substantially aligned in accordance with at least part of a surface of revolution, and wherein the plurality of reflective magnetic platelets are aligned to cause a first reflective effect of the optical article when the substrate is rotated around a first axis and to cause a second reflective effect of the optical article when the substrate is rotated around a second axis, wherein the first reflective effect is different from the second reflective effect.

Examples disclosed herein relate to an imaging device. The imaging device to include a discharge member to discharge a first pattern on a photoconductor; and a writing engine to control the discharge member to discharge a second pattern to the photoconductor to obscure any latent pattern formed from the first pattern remaining on the photoconductor.

An optical article printed on a substrate may include an organic binder; and a plurality of reflective magnetic platelets provided in the organic binder, wherein the plurality of reflective magnetic platelets are substantially aligned in accordance with at least part of a surface of revolution, and wherein the plurality of reflective magnetic platelets are aligned to cause a first reflective effect of the optical article when the substrate is rotated around a first axis and to cause a second reflective effect of the optical article when the substrate is rotated around a second axis, wherein the first reflective effect is different from the second reflective effect.

Examples disclosed herein relate to an imaging device. The imaging device to include a discharge member to discharge a first pattern on a photoconductor; and a writing engine to control the discharge member to discharge a second pattern to the photoconductor to obscure any latent pattern formed from the first pattern remaining on the photoconductor.

A redundantly printed security-enhanced document, printing method and system ensure the meaning of the information imparted by variable indicia printed by redundant printing on the document with removable scratch-off coatings. By printing the variable indicia with multiple colors, redundancy and integrity of the intended indicia is achieved. Additionally, inverted color indicia countermeasures to pinprick attacks are also disclosed. The redundantly printed document, methods and systems enhance the overall appearance of the redundantly printed document, and reduce possible consequences resulting from misprinted variable indicia. The resultant printed process color indicia maintains a grayscale equivalent level of a process color greater than or equal to the measured grayscale equivalent level of the substrate surface plus an additional contrast delta of 15%.

A redundantly printed security-enhanced document, printing method and system ensure the meaning of the information imparted by variable indicia printed by redundant printing on the document with removable scratch-off coatings. By printing the variable indicia with multiple colors, redundancy and integrity of the intended indicia is achieved. Additionally, inverted color indicia countermeasures to pinprick attacks are also disclosed. The redundantly printed document, methods and systems enhance the overall appearance of the redundantly printed document, and reduce possible consequences resulting from misprinted variable indicia. The resultant printed process color indicia maintains a grayscale equivalent level of a process color greater than or equal to the measured grayscale equivalent level of the substrate surface plus an additional contrast delta of 15%.