Near-Infrared Transmission Compound for Low Visible Light Halation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing near-infrared transmission materials using titanium oxide or zinc oxide blended with transparent resins suffer from increased visible light transmittance and durability issues due to photocatalytic performance and weather resistance concerns.

Innovation Solution

A compound containing elements such as H, alkali metals, alkaline earth metals, rare earth elements, and transition metals like Mn, Cr, Fe, and Ni, formulated to have low visible light reflectance and high near-infrared transmittance, with specific compositional ratios and forms including oxides, nitrides, and sulfides.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If titanium oxide or zinc oxide is blended with transparent resin to create a near-infrared transmission coating, then near-infrared transmittance is improved, but visible light transmittance increases and resin durability deteriorates due to photocatalytic performance

Engineering Contradiction:
Improvenear-infrared transmittanceVSAvoidresin durability
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent changes the material parameters by replacing titanium oxide/zinc oxide with a specific compound having controlled compositional ratios (0.1≤x≤2.0, 0.1≤y≤2.0, 2.2≤z≤4.0 in formula AxByOz). This compositional parameter adjustment enables the material to achieve high near-infrared transmittance while suppressing visible light transmittance and eliminating photocatalytic activity, thereby resolving the contradiction between near-infrared performance and resin durability.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent employs a composite material approach by creating a coating comprising compound particles (with specific multi-element composition) dispersed in a transparent resin. This composite structure allows the compound particles to provide selective optical transmission properties while remaining inert to the resin, thus achieving both high near-infrared transmittance and maintained resin durability without photocatalytic degradation.

Inventive Principle:
Principle #40Composite materials

2Measurement precision

If azo-based dye pigment is blended with transparent resin to create a near-infrared transmission coating, then near-infrared transmittance is improved, but weather resistance and durability worsen due to ultraviolet ray sensitivity

Engineering Contradiction:
Improvenear-infrared transmittanceVSAvoidweather resistance
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent replaces the unstable organic azo-based dye pigment with an inorganic compound (AxByOz) that exhibits superior stability and durability. This substitution uses an inorganic material that is inherently resistant to ultraviolet radiation and environmental degradation, thereby achieving high near-infrared transmittance while dramatically improving weather resistance and long-term durability.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent creates a composite coating material combining inorganic compound particles (AxByOz) with transparent resin. This composite structure provides the benefits of both components: the inorganic compound delivers high near-infrared transmittance and UV resistance, while the resin provides structural integrity and adhesion, resulting in a coating with superior overall weather resistance compared to organic dye-based coatings.

Inventive Principle:
Principle #40Composite materials

3Measurement precision

If a coating material is designed to transmit only near-infrared rays and block visible light, then detection precision is improved, but diffuse reflection increases causing halation

Engineering Contradiction:
Improvedetection precisionVSAvoiddiffuse reflection
Core Design Contradiction:
Measurement precisionVSObject-generated harmful factors

Solution Approach 1:

The patent adjusts the optical parameters of the coating by controlling the compositional ratios (x, y, z) of the compound AxByOz. This parameter optimization enables the coating to achieve selective transmission in the near-infrared region while simultaneously suppressing diffuse reflection in the visible region, thereby eliminating halation effects and improving detection precision without compromising optical quality.

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 compound achieves low visible light transmission and high near-infrared transmission, enhancing performance in infrared sensors and cameras by preventing diffuse reflection and improving durability.

Implementation Method 1

a compound... having a low transmittance in a visible light region and a high transmittance in a near-infrared region

Methodology Applied
Scientific EffectOptical absorption: Absorption (EM radiation)

Implementation Method 2

excellent in performance of preventing diffuse reflection (halation) of light in the visible light region

Methodology Applied
Scientific EffectDiffuse reflection prevention: Reflection

Data Source

PatentEP4678599A1Compound, compound particles, near-infrared transmission material, and near-infrared transmission film
Publication Date: 2026.01.14 MITSUI MINING & SMELTING CO LTD
  • EP4678599A1 patent drawingFigure 1
  • EP4678599A1 patent drawingFigure 2
  • EP4678599A1 patent drawingFigure 3

AI summary

A compound of the present invention contains, as a constituent element, two or more elements selected from H, an alkali metal, an alkaline earth metal, a rare earth element, B, F, Al, Si, P, S, Cl, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Se, Br, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, I, Hf, Ta, W, Re, Os, Ir, Pt, Tl, Pb, and Bi.