Infrared Absorbing Fine Particles for Invisibility and Fastness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current near-infrared absorptive dyes lack both high invisibility and durability, as they tend to absorb visible light when concentrated, leading to reduced fastness and invisibility issues.
Innovation Solution
Development of a dispersion comprising fine particles of a novel compound represented by specific formulas, which absorb in the near-infrared range without absorbing in the visible range, combined with a surfactant, to enhance both invisibility and light fastness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If near-infrared absorptive dyes are used in high concentration, then infrared absorption intensity is improved, but visible range absorption is generated causing loss of invisibility
Solution Approach 1:
The invention divides the dye molecules into separate fine particles dispersed in a carrier. By segmenting the dye into discrete particles rather than using high concentrations of molecular dye, the patent achieves strong infrared absorption while preventing the molecular association that causes visible range absorption. The fine particle structure allows high infrared absorptivity without the harmful visible absorption that occurs in concentrated molecular solutions.
Solution Approach 2:
The invention changes the physical state and size parameters of the dye by converting it into fine particles with specific size ranges (0.1-10 μm). This parameter change from molecular dispersion to particulate form fundamentally alters the optical properties, enabling strong infrared absorption while maintaining invisibility in the visible range, even at high effective concentrations.
2Quantity of substance
If cyanine methine dyes with long methine conjugated chains are used, then infrared absorption is improved, but the dyes are easily isomerized and decomposed reducing fastness
Solution Approach 1:
The invention creates a composite structure where the dye molecules are encapsulated within fine particles of a carrier material. This composite approach protects the dye molecules from environmental factors such as oxygen, moisture, and nucleophilic agents that cause decomposition. The carrier material acts as a protective matrix, maintaining the dye's infrared absorption properties while significantly improving its chemical stability and fastness.
Solution Approach 2:
The fine particle structure provides preliminary protection against decomposition mechanisms. By encapsulating the dye molecules in the carrier matrix before exposure to degrading conditions, the structure prevents oxygen and nucleophilic agents from attacking the dye, thereby preemptively protecting against isomerization and decomposition that would reduce fastness.
3Reliability
If vanadylphthalocyanine dyes with rigid skeleton are used, then fastness is improved, but invisibility is insufficient due to visible range absorption
Solution Approach 1:
The invention changes the optical parameters by converting the dye into fine particles with controlled size and dispersion characteristics. This particle form modification alters the way light interacts with the material, enabling the retention of fastness properties while eliminating the visible range absorption that plagues conventional vanadylphthalocyanine dyes. The fine particle structure creates optimal light scattering and absorption characteristics.
4Object-generated harmful factors
If diimmonium dyes are used, then invisibility and broad infrared absorption are improved, but the dyes are easily reducible reducing fastness
Solution Approach 1:
The invention forms a composite where diimmonium dye molecules are dispersed within fine particles of a carrier material. This composite structure protects the reducible dye molecules from reducing agents in the environment. The carrier material acts as a barrier, preventing direct contact between the dye and reducing substances, thereby maintaining both the excellent invisibility and broad infrared absorption of diimmonium dyes while significantly improving their fastness.
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 provides a near-infrared absorptive dye with excellent invisibility and high fastness, suitable for applications requiring selective infrared absorption and resistance to light degradation.
Implementation Method 1
a compound which shows absorption in a near-infrared range, but does not show absorption in a visible range
Data Source
Figure 1~3
Figure 4
AI summary
A fine particle which contains a compound represented by formula (1): wherein R1a and R1b may be the same or different, and each independently represent an alkyl group, an aryl group, or a heteroaryl group; R2 and R3 each independently represent a hydrogen atom or a substituent, and at least one of R2 and R3 is an electron withdrawing group; R2 may be bonded to R3 to form a ring; R4 represents a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, a substituted boron, or a metal atom; and R4 may be covalently bonded or coordinately bonded to at least one among R1a, R1b and R3.