Variable Speed UV Curing for Flat Top Printing Plates

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for producing photo-curable printing plates, particularly digital plates, struggle to achieve flat top features, as they often result in rounded surfaces due to the difficulty in controlling the shape of three-dimensional printing features like halftone dots, requiring additional equipment and workflows to simulate analog processes for flat top production.

Innovation Solution

An apparatus and method that control the shape of three-dimensional printing features by varying the speed of relative motion between a light exposure unit and the printing plate during UV curing, allowing for the production of either flat top or round top halftone dots by adjusting the period of illumination, maintaining consistent UV dose for complete curing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Shape

If conventional UV curing methods are used on digital plates, then curing is achieved, but the printing features have rounded surfaces instead of flat tops

Engineering Contradiction:
Improveshape of printing featuresVSAvoidprecision of flat top production
Core Design Contradiction:
ShapeVSManufacturing precision

Solution Approach 1:

The patent applies dynamics by varying the rotational speed of the printing plate during UV curing. The system transitions from constant speed to variable speed, where the plate rotates slower when the UV light source is illuminating and faster when not illuminated. This dynamic speed adjustment allows the same digital workflow to produce both flat top and round top features by controlling the illumination duration on each feature, thereby resolving the contradiction between achieving proper curing and obtaining the desired flat top shape.

Inventive Principle:
Principle #15Dynamics

2Shape

If additional equipment is added to produce flat top features on digital plates, then flat top production is achieved, but device complexity increases

Engineering Contradiction:
Improveflat top feature productionVSAvoidequipment requirements
Core Design Contradiction:
ShapeVSDevice complexity

Solution Approach 1:

The patent implements universality by making the UV curing apparatus capable of producing multiple feature types (flat top and round top) using the same digital workflow and equipment. Instead of requiring separate equipment for different feature shapes, the system uses variable speed control during a single curing process to achieve different outcomes. This eliminates the need for additional specialized equipment while maintaining the ability to produce various feature shapes on demand.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Reliability

If UV light intensity is increased to improve curing, then curing effectiveness is improved, but rounded surfaces are exacerbated

Engineering Contradiction:
Improvecuring effectivenessVSAvoidsurface shape of printing features
Core Design Contradiction:
ReliabilityVSShape

Solution Approach 1:

The patent applies periodic action by creating a cyclical pattern of illumination and non-illumination during the curing process. The printing plate rotates through positions where it is illuminated by the UV light source and positions where it is not illuminated. This periodic exposure, combined with variable speed control that slows the plate during illumination, allows sufficient curing time at high intensity while preventing the excessive rounding that would occur with continuous high-intensity exposure.

Inventive Principle:
Principle #19Periodic action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables operators to choose between flat top and round top features using the same digital workflow, improving precision and reducing equipment needs, with the ability to produce flat tops at slower rotational speeds and round tops at faster speeds, while maintaining effective curing.

Implementation Method 1

Photo-curable, of course, means curable by photons, e.g., light, e.g., light in the ultraviolet range or some other range

Methodology Applied
Scientific EffectPhotopolymerization: Photopolymerisation

Data Source

PatentEP2317387B1Curing of photo-curable printing plates with flat tops or round tops by variable speed exposure
Publication Date: 2018.12.26 ESKO GRAPHICS IMAGING
  • EP2317387B1 patent drawingFigure 1
  • EP2317387B1 patent drawingFigure 2
  • EP2317387B1 patent drawingFigure 3

AI summary

An apparatus for curing a printing plate made of or having photo-curable material, a method of curing such a printing plate, and a printing plate cured by the method. One embodiment of the method includes curing a printing plate made of or having photo-curable material thereon. The method includes producing light energy on part of the printing plate using a light exposure unit, including relative motion between the light energy and the plate in a transverse direction at a changeable period of repetition, such that curing can produce printing features on the plate that can be switched to have either flat tops or round tops according to the period of repetition.