UV Printing Plate Exposure Cooling to Limit Thermal Polymerization

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing curing methods for photopolymer printing plates fail to efficiently prevent thermal polymerization, leading to unwanted broadening of small features and distortion of tone curves due to excessive warming during UV exposure.

Innovation Solution

A system and method that directs cooling air from the trailing edge of the radiation source to the leading edge during UV exposure, optimizing cooling efficiency by minimizing temperature peaks on the photopolymer surface.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If cooling air is directed from the leading edge to the trailing edge during UV exposure, then the polymer is cooled during exposure, but thermal polymerization still occurs causing feature broadening and tone curve distortion

Engineering Contradiction:

Improvepolymer temperature during exposureVSAvoidfeature dimensions and tone curves

Core Design Contradiction:

TemperatureVSManufacturing precision

Solution Approach 1:

The patent inverts the conventional cooling air flow direction. Instead of blowing air from the leading edge to the trailing edge, the system directs cooling air from the trailing edge toward the leading edge of the moving UV exposure head. This reversed flow direction allows the coolest air to contact the polymer at the trailing edge where the UV head has just passed, providing maximum cooling effectiveness precisely when and where the polymer needs it most, thereby preventing thermal polymerization and maintaining feature precision

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The cooling air system is positioned and timed to provide cooling action immediately after UV exposure at each location on the polymer. By directing air from the trailing edge, the system ensures that cooling begins as soon as the UV head passes a given point, preventing temperature buildup before it can cause thermal polymerization. This preliminary cooling action occurs at the optimal moment in the exposure cycle

Inventive Principle:

Principle #10Preliminary action

2Productivity

If UV exposure is performed with a moving head, then productivity is improved, but thermal polymerization occurs due to accumulated heat

Engineering Contradiction:

Improveexposure speedVSAvoidthermal polymerization

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent employs a pneumatic cooling system that delivers a controlled stream of cooling air into the exposure gap between the UV head and the polymer. This pneumatic approach allows for rapid, localized cooling without mechanical contact, enabling high-speed moving head exposure while simultaneously removing heat that would otherwise cause thermal polymerization. The air stream acts as a mobile heat sink that travels with the exposure head

Inventive Principle:

Principle #29Pneumatics and hydraulics

Solution Approach 2:

Cooling air serves as an intermediary medium between the UV exposure head and the polymer substrate. This gas-phase mediator transfers heat away from the polymer surface during the exposure process, allowing high-speed UV curing without the harmful thermal effects. The air stream absorbs and carries away excess heat, enabling the moving head system to operate at high productivity while preventing thermal polymerization

Inventive Principle:

Principle #24Intermediary (Mediator)

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

Reduces thermal polymerization effects, maintaining precise feature dimensions and tone curves by effectively controlling temperature fluctuations during UV curing.

Implementation Method 1

a cooling air handling system configured to direct a volume of cooling air into the gap between the radiation source and the printing plate only in a direction from the trailing edge to the leading edge

Methodology Applied

Scientific EffectConvection: Convection

Implementation Method 2

curing a photopolymer printing plates curable by exposure to actinic radiation

Methodology Applied

Scientific EffectPhotopolymerization: Photopolymerisation

Data Source

PatentUS12547077B2Printing plate exposure method and apparatus with reduced thermal polymerization

Publication Date: 2026.02.10 ESKO GRAPHICS IMAGING

AI summary

Systems and methods for curing a photopolymer printing plates. A radiation source, such as an UV LED source having a radiation-emitting lateral dimension in a range 10-60 cm, is spaced from a substrate that holds the printing plate. The source and substrate are configured to move relative to one another in a movement direction that defines a leading edge of the radiation source and a trailing edge of the radiation source. A cooling air handling system directs a volume of cooling air into the gap between the radiation source and the printing plate in a direction from the trailing edge to the leading edge. The cooling air handling system may have one or more outlets attached at least one edge of the source, may be configured to only direct air from the trailing edge to the leading edge, or a combination thereof.