Sheet-fed Press for Security Elements with Optically Variable Structures
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of security elements with optically variable structures is costly and limited by decoupled printing and embossing processes, which hinder high-speed mass production due to the need for multiple steps and intaglio printing.
Innovation Solution
A method for producing security elements using a sheet-fed printing press that integrates a printing unit for a repeating pattern coating and an embossing unit for a finely structured embossing structure, ensuring register accuracy and high processing speeds through circulating gripper systems, with flexible embossing plates and soft embossing bases, allowing for the creation of optically variable structures on thin substrates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If decoupled printing and embossing processes are used, then manufacturing precision can be maintained, but productivity decreases and production cost increases
Solution Approach 1:
The patent combines the printing unit and embossing unit into a single integrated system that operates simultaneously on the same substrate. The printing unit applies the repeating pattern coating while the embossing unit creates the finely structured embossing in the same processing cycle, eliminating the need for separate decoupled processes and enabling high-speed production without compromising register accuracy.
2Manufacturing precision
If intaglio printing is used for fine embossing structures, then manufacturing precision is achieved, but productivity decreases due to limited printing speed
Solution Approach 1:
The patent replaces the traditional intaglio printing mechanical system with a hybrid approach where a printing unit applies coating material that is then simultaneously embossed. This substitution allows for higher printing speeds while maintaining the precision of fine embossing structures through the coordinated action of the printing and embossing units operating in registration.
3Manufacturing precision
If multiple process steps are used for security element production, then manufacturing precision is maintained, but device complexity increases and productivity decreases
Solution Approach 1:
The patent merges multiple separate process steps into a single integrated printing and embossing unit. The printing unit and embossing unit are combined to operate simultaneously on the substrate in registration, reducing the total number of process steps and equipment complexity while maintaining the precision required for security element production.
4Ease of manufacture
If conventional embossing is used on thin substrates, then manufacturing simplicity is maintained, but the substrate may be damaged
Solution Approach 1:
The patent modifies the embossing parameters by using a printing unit to apply coating material that serves as a protective layer during the embossing process. This parameter change allows the embossing unit to create fine structures on thin substrates without damaging them, as the coating material provides support and protection during the embossing operation.
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The invention relates to a sheet-fed press (40) for printing and embossing printed sheets (50) for producing security elements (14) with an optically variable structure (20), comprising at least one printing unit (44-1, 44-2), which is designed and equipped to coat (22) the printed sheets (50) with a repeating pattern (22-1, 22-2), an embossing unit (46) which is designed and equipped to provide the printed sheets (50) with a fine-structured embossing structure (26), and comprising conveying systems for guiding the printed sheets (50) within the sheet-fed press (40) on a peripheral gripping structure, the printed sheets being gripped through the at least one printing unit (44-1, 44-2) and the embossing unit (46) in order to produce the finely structured embossing structure (26) and to apply the coating (22) in an adapted manner to the printed sheets (50) and to thus form the optically variable structure (20) of the security element (14) which is to be produced. The invention also relates to a method for producing a security element with an optically variable structure (20) in said type of sheet-fed press, a flexible embossing plate (70) for said type of sheet-fed press and to a method for producing said type of embossing plate.