Printed Security Element Rainbow Feature via Dual-Plate Register
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rainbow printing technologies for security elements are limited by the need for specialized equipment, restricting the types of printed security elements that can be produced and offering limited flexibility in design, especially for two-dimensional rainbow printing.
Innovation Solution
A method involving two distinct printing plates with linear or curvilinear elements that are printed in register to create a rainbow feature with a gradual transition from one color to another, allowing for modulation of line width or structure to achieve the color transition, enabling greater design flexibility without the need for complex equipment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If dedicated inking systems with multiple inking units are used for two-dimensional rainbow printing, then rainbow features with gradual color transitions can be achieved, but device complexity and design restrictions increase
Solution Approach 1:
The printing process is segmented into two independent printing operations using separate printing plates. Each plate carries a portion of the final pattern, and the two are printed in register to create the rainbow effect. This divides the complex inking system into simpler, independent printing units that can be operated separately while maintaining precise registration.
Solution Approach 2:
The patent transitions from a single-plate multi-inking approach to a multi-plate approach, adding the dimension of multiple printing surfaces. This allows the rainbow feature to be created through the superposition of patterns from different plates rather than through complex inking of a single plate, simplifying the inking system while maintaining color transition precision.
2Manufacturing precision
If specialized printing equipment is used for rainbow printing, then gradual color transitions can be achieved, but adaptability and versatility of production are reduced
Solution Approach 1:
The printing plates can be designed with various patterns and configurations to produce different rainbow features and security elements. The same basic printing equipment can be used for different applications by simply changing the printing plate designs, making the system universal and adaptable to various security document requirements rather than requiring specialized equipment for each design.
Solution Approach 2:
The rainbow effect is achieved by modulating parameters such as line width, line structure, or spacing of the printed patterns on the plates. By changing these parameters in the plate design, different color transition effects can be produced without changing the fundamental printing equipment, thereby increasing versatility while maintaining precision.
3Ease of manufacture
If two inks are mixed along a single axial direction using vibrator rollers, then one-dimensional rainbow printing is achieved, but design freedom for two-dimensional patterns is limited
Solution Approach 1:
Instead of mixing two inks along a single axial direction, the patent segments the pattern into two separate printed patterns on different plates. Each plate can be designed with independent linear or curvilinear elements that are printed in register, allowing two-dimensional pattern design freedom while keeping each individual printing process simple and straightforward.
Data Source
AI summary
There is described a printed security element (10; 10*; 10**) comprising a rainbow feature (15; 15*; 15**) exhibiting, at least in part, a gradual transition from a first colour (C1) to a second colour (C2) distinct from the first colour (C1), wherein the rainbow feature (15; 15*; 15**) extends over a colour-gradient area (A) of the printed security element (10; 10*; 10**) where first and second printed patterns (P1, P2) are partly superimposed or juxtaposed, each of the first and second printed patterns (P1, P2) comprising a first, respectively second set of linear or curvilinear elements (20, 30; 20*, 30*), the first and second printed patterns (P1, P2) being printed in register one with the other by means of two distinct printing plates (PP1, PP2) so that the first and second sets of linear or curvilinear elements (20, 30; 20*, 30*) are partly superimposed or juxtaposed in the colour-gradient area (A) and thereby generate the rainbow feature (15; 15*; 15**), the first printed pattern (P1) exhibiting the first colour (C1) and being printed by means of a first printing plate (PP1) and the second printed pattern (P2) exhibiting the second colour (C2) and being printed by means of a second printing plate (PP2), where at least the first or second printed pattern (P1; P2) exhibits, in the colour-gradient area (A), a modulation of line width or line structure such as to cause, when superimposed or juxtaposed with the other printed pattern (P2; P1), a gradual transition from the first colour (C1) to the second colour (C2), wherein, in the colour-gradient area (A), the second printed pattern (P2) is printed on top of the first printed pattern (P1) and wherein the second colour (C2) is darker than the first colour (C1). Also described is a method of producing the aforementioned printed security element.