Photosensitive Colored Composition Stabilizing Pattern Formation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for producing color filters, particularly those using pigment dispersion, face challenges in achieving stable pattern formation with low illuminance, leading to variations in line width, film thickness, and scattering spectrum, which are difficult to control, especially when exposure is performed at low illuminance levels.

Innovation Solution

A photosensitive colored composition comprising a pigment, a polymerizable monomer, a photopolymerization initiator, and a specific ultraviolet absorber represented by a conjugated diene compound, which helps stabilize pattern formation by reducing dependency on exposure illuminance, ensuring high film retention and minimal developing residue.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the amount of photopolymerization initiator is increased to improve dependency on exposing illuminance, then the resolution and pattern stability are improved, but the line width becomes excessively wide and circumferential residue is generated

Engineering Contradiction:

Improvedependency on exposing illuminanceVSAvoidline width control

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The patent changes the chemical parameters of the photopolymerization system by introducing a specific photopolymerization initiator (compound with formula (I)) that has different photochemical properties compared to conventional initiators. This new initiator requires higher illuminance for activation but provides more stable and controlled polymerization, thereby reducing dependency on varying illuminance levels while maintaining precise line width control and minimizing circumferential residue.

Inventive Principle:

Principle #35Parameter changes

2Manufacturing precision

If the amount of photopolymerization initiator is reduced to narrow line width, then the line width precision is improved, but the dependency on exposing illuminance increases

Engineering Contradiction:

Improveline widthVSAvoiddependency on exposing illuminance

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

The patent introduces a novel photopolymerization initiator with specific chemical structure (formula (I)) that alters the photochemical reaction characteristics. This initiator maintains narrow line width by controlling the activation threshold while simultaneously reducing sensitivity to illuminance variations, thereby improving reliability across different exposure conditions without sacrificing line width precision.

Inventive Principle:

Principle #35Parameter changes

3Manufacturing precision

If antioxidant is added to improve resolution and suppress lowering of sensitivity, then the pattern resolution is improved, but the line width variation and film thickness variation increase

Engineering Contradiction:

ImproveresolutionVSAvoidline width and film thickness uniformity

Core Design Contradiction:

Manufacturing precisionVSStability of the object's composition

Solution Approach 1:

The patent modifies the chemical composition parameters by replacing conventional antioxidants with a specific photopolymerization initiator (compound (I)) that has dual functionality: it acts as both the initiation source and a stability controller. This approach improves resolution through controlled polymerization while maintaining uniform line width and film thickness by avoiding the adverse effects of traditional antioxidants on composition stability.

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 solution enables the production of color filters with consistent pattern quality and high resolution, capable of displaying fine images, even under low illuminance conditions, by stabilizing line width and film thickness, and reducing exposure-dependent variations.

Implementation Method 1

the irradiation with the ultraviolet rays causes the photopolymerization initiator to generate an activated radical, and the activated radical attacks a polymerizable group such as a (meth)acryloyl group and provokes a polymerization reaction

Methodology Applied

Scientific EffectPhotopolymerization: Photopolymerisation

Implementation Method 2

a specific ultraviolet absorber represented by a conjugated diene compound, which helps stabilize pattern formation by reducing dependency on exposure illuminance

Methodology Applied

Scientific EffectUltraviolet absorption: Absorption (EM radiation)

Data Source

PatentEP2246739B1Photosensitive colored composition, color filter and method for producing the same

Publication Date: 2012.07.04 FUJIFILM CORP

AI summary

There is provided a photosensitive colored composition including a pigment, a polymerizable monomer, a photopolymerization initiator, and a compound represented by a general formula (I) [Each of R1 and R2 independently represents a hydrogen atom, an alkyl group with 1 to 20 carbon atoms, or an aryl group with 6 to 20 carbon atoms, where although R1 and R2 may be the same or different from each other, R1 and R2 do not represent a hydrogen atom at the same time. R1 and R2 may form a cyclic amino group with a nitrogen atom; and each of R3 and R4 independently represents an electron withdrawing group.]