Inkjet Recording Method for Package Printing

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing ink jet recording methods face issues with migration and character blurring, particularly in package printing, due to unreacted monomers and polymerization initiator residues transferring to packaged objects, leading to high elution amounts and poor image clarity.

Innovation Solution

An ink jet recording method that uses an ink composition containing 3-methyl pentanediol diacrylate as 30 mass % or more, irradiated in an atmosphere with oxygen partial pressure of 0.10 atm or less, along with a multifunctional acrylate compound and a bisacylphosphine compound, to form a cross-linked structure that suppresses migration and improves character clarity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If a radiation-curable ink composition is used for ink jet recording, then the drying property is improved and images do not run easily, but the elution amount of components to the outside increases and character blurring occurs

Engineering Contradiction:

Improvedrying propertyVSAvoidelution amount and character blurring

Core Design Contradiction:

Stability of the object's compositionVSObject-generated harmful factors

Solution Approach 1:

The patent changes the chemical composition parameters of the ink by specifying 3-methyl pentanediol diacrylate content at 30-95 mass% and controlling the molecular weight of multifunctional acrylate compounds to 315 or more. These parameter changes optimize the balance between curing efficiency and reduction of low-molecular-weight components that cause elution and character blurring.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses a composite ink composition system combining 3-methyl pentanediol diacrylate with multifunctional acrylate compounds (molecular weight 315 or more) and specific polymerization initiators. This composite approach creates a synergistic effect where the high molecular weight acrylate provides structural integrity while the specific initiator system ensures complete curing, reducing both elution and character blurring.

Inventive Principle:

Principle #40Composite materials

2Manufacturing precision

If conventional ink compositions are used, then character clarity is maintained, but migration to packaged objects occurs and blocking resistance is poor

Engineering Contradiction:

Improvecharacter clarityVSAvoidmigration and blocking

Core Design Contradiction:

Manufacturing precisionVSObject-generated harmful factors

Solution Approach 1:

The patent changes the molecular weight parameter of the acrylate compounds to 315 or more, which reduces migration while maintaining character clarity. The specific composition ratio of 3-methyl pentanediol diacrylate (30-95 mass%) also optimizes the balance between printability and migration resistance.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs a disposable-like approach by using a single-pass ejection system where the ink is ejected and immediately cured without requiring complex multi-step processing. This simplifies the system while achieving the desired performance through optimized ink composition rather than complex apparatus.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Ease of operation

If the ink composition contains low molecular weight components, then ejection performance is improved, but elution and migration increase

Engineering Contradiction:

Improveejection performanceVSAvoidelution and migration

Core Design Contradiction:

Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The patent optimizes the viscosity parameter by controlling the molecular weight of multifunctional acrylate compounds to be 315 or more and adjusting the composition ratio of 3-methyl pentanediol diacrylate to 30-95 mass%. This parameter optimization ensures the ink has appropriate ejection performance while minimizing low-molecular-weight components that cause elution and migration.

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

The method significantly reduces migration and character blurring, resulting in a printed material with improved blocking resistance and odor control, suitable for package printing applications.

Implementation Method 1

irradiating active rays in an atmosphere where the oxygen partial pressure is 0.10 atm or less to cure the ink composition

Methodology Applied

Scientific EffectPhotopolymerization: Photopolymerisation

Implementation Method 2

irradiating active rays in an atmosphere where the oxygen partial pressure is 0.10 atm or less

Methodology Applied

Scientific EffectOxygen inhibition: Oxidation

Data Source

PatentUS9290015B2Inkjet recording method and printed material

Publication Date: 2016.03.22 FUJIFILM CORP

AI summary

The object of the present invention is to provide an ink jet recording method where it is possible to obtain a printed material where the elution amount (migration) to the outside of the components in a cured ink composition is small and there is little character blurring, and a printed material. The ink jet recording method of the present invention includes a step of ejecting an ink composition which contains 3-methyl pentanediol diacrylate of 30 mass % or more with respect to the total ink composition from an ink jet head onto a support, and a step of irradiating active rays in an atmosphere where the oxygen partial pressure is 0.10 atm or less to cure the ink composition.