Hybrid Wet-on-Wet Printing With Electron Beam Curing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Wet on wet printing methods often result in merging or bleeding between different ink types, leading to low color strength, mottling, puddling, and poor image quality, particularly in high-value applications requiring high-quality image reproduction.

Innovation Solution

A hybrid wet on wet printing method combining radiation curable analog and digital inks, where one ink is applied while the other is still wet, followed by electron beam radiation to at least partially cure both inks, ensuring compatibility and rapid curing to prevent bleeding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If wet on wet printing is used to accelerate the printing process, then productivity is improved, but merging or bleeding between ink layers occurs leading to poor image quality

Engineering Contradiction:
Improveprinting speedVSAvoidimage quality
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The patent applies parameter changes by modifying the surface tension and viscosity parameters of the ink compositions. Specifically, the first ink composition has a surface tension of 20-40 mN/m and the second ink composition has a surface tension of 15-30 mN/m, creating controlled surface property differences that enable wet on wet printing without excessive merging or bleeding, thus maintaining image quality while increasing productivity

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses composite materials by combining radiation curable analog ink composition with radiation curable inkjet ink composition in a hybrid wet on wet printing process. This composite approach allows different ink types to be applied sequentially without complete drying, achieving both high productivity and acceptable image quality through the synergistic properties of the combined ink systems

Inventive Principle:
Principle #40Composite materials

2Manufacturing precision

If multiple drying and curing steps are applied to prevent ink merging, then image quality is maintained, but production time and energy consumption increase

Engineering Contradiction:
Improveimage qualityVSAvoidproduction time
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The patent merges (combines) multiple functions into a single step by performing both drying and curing operations simultaneously in one passage through the printing system. This eliminates the need for separate drying and curing steps, reducing production time while maintaining image quality through the combined action of the radiation curable ink compositions

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent implements continuity of useful action by maintaining the ink compositions in a wet state during sequential application and then curing them in a single continuous pass. This continuous process without interruption or waiting periods for separate drying/curing steps significantly reduces production time while preserving image quality through controlled surface tension and viscosity parameters

Inventive Principle:
Principle #20Continuity of useful action

3Manufacturing precision

If different surface properties are assigned to each ink layer to prevent bleeding, then ink layer separation is improved, but formulation complexity increases

Engineering Contradiction:
Improveink layer separationVSAvoidink formulation complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent applies parameter changes by systematically adjusting surface tension and viscosity parameters of the ink compositions. The first ink composition has surface tension of 20-40 mN/m and the second has 15-30 mN/m, creating controlled surface property differences that facilitate proper ink layer separation without requiring overly complex formulations, thus balancing ink layer separation with formulation simplicity

Inventive Principle:
Principle #35Parameter changes

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

This method produces sharp, clear, high-quality images with increased printing speeds and reduced energy costs by avoiding multiple drying and curing operations.

Implementation Method 1

exposing to electron beam radiation

Methodology Applied
Scientific EffectElectron beam radiation: Electron Beam

Implementation Method 2

radiation curable inkjet ink composition

Methodology Applied
Scientific EffectRadiation curing: Photopolymerisation

Data Source

PatentEP3847032B1Hybrid wet on wet printing methods
Publication Date: 2025.12.03 KAO CORP
  • EP3847032B1 patent drawingFigure 1
  • EP3847032B1 patent drawingFigure 2

AI summary

A method of forming an image on a substrate that includes applying a radiation curable analog ink composition by an analog printing method onto a surface of the substrate to form a coated substrate, applying a radiation curable inkjet ink composition by a digital printing method onto the coated substrate while the radiation curable analog ink composition is still wet to form a hybrid coated substrate, and exposing to electron beam radiation. A method of forming an image on a substrate that includes applying a radiation curable inkjet ink composition by a digital printing method onto a surface of the substrate to form a coated substrate, applying a radiation curable analog ink composition by an analog printing method onto the coated substrate while the radiation curable inkjet ink composition is still wet to form a hybrid coated substrate, and exposing to electron beam radiation.