Zirconium Oxide Phosphor with Titanium and Co-dopants

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current phosphors using rare earth elements are expensive and have limited reserves, and existing zirconium oxide-based phosphors with added titanium do not achieve high fluorescence levels, necessitating the development of cost-effective oxide-based phosphors with high luminous efficacy using elements other than rare earths.

Innovation Solution

A zirconium oxide-based phosphor comprising titanium and at least one of phosphorus, selenium, boron, or silicon, produced through a method involving a zirconium compound slurry, neutralization, and high-temperature heating, which exhibits fluorescence upon ultraviolet excitation without using rare earth elements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If rare earth elements are used as light-emitting elements in phosphors, then high luminous efficacy is achieved, but material costs increase and reserves are limited

Engineering Contradiction:
Improveluminous efficacyVSAvoidmaterial reserves
Core Design Contradiction:
Use of energy by moving objectVSQuantity of substance

Solution Approach 1:

The patent replaces expensive rare earth elements with abundant, inexpensive elements (titanium at 0.05-0.8 wt% combined with phosphorus, selenium, boron, or silicon) to create a cost-effective phosphor material that achieves high luminous efficacy without relying on limited rare earth resources

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

Solution Approach 2:

The patent optimizes the concentration of titanium (0.05-0.8 wt%) and co-dopants (0.001-5.0 wt%) to achieve high luminous efficacy, demonstrating that precise parameter control of abundant elements can substitute for rare earth elements in terms of performance

Inventive Principle:
Principle #35Parameter changes

2Device complexity

If titanium is added to zirconium oxide to achieve fluorescence, then the phosphor structure is simplified, but fluorescence intensity remains low

Engineering Contradiction:
Improvephosphor compositionVSAvoidfluorescence intensity
Core Design Contradiction:
Device complexityVSIllumination intensity

Solution Approach 1:

The patent creates a composite phosphor system combining zirconium oxide with titanium and co-dopants (phosphorus, selenium, boron, or silicon), where the synergistic interaction between multiple elements achieves high fluorescence intensity while maintaining compositional simplicity

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The co-dopants (phosphorus, selenium, boron, or silicon) act as intermediaries that enhance the fluorescence properties of titanium-doped zirconium oxide, mediating between the simple host structure and the desired high-intensity fluorescence output

Inventive Principle:
Principle #24Intermediary (Mediator)

3Quantity of substance

If alternative elements (phosphorus, selenium, boron, silicon) are added to zirconium oxide with titanium, then material costs decrease, but achieving high fluorescence characteristics becomes difficult

Engineering Contradiction:
Improvematerial availabilityVSAvoidfluorescence performance
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The patent establishes specific concentration ranges for titanium (0.05-0.8 wt%) and co-dopants (0.001-5.0 wt%) to optimize fluorescence performance, demonstrating that precise parameter control enables abundant elements to reliably achieve high luminous efficacy comparable to rare earth phosphors

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 zirconium oxide-based phosphor achieves high fluorescence intensity and wavelength conversion from ultraviolet to visible light, offering a cost-effective solution for applications like photovoltaic devices, LEDs, and plasma displays.

Implementation Method 1

the phosphor consists of the following (1) to (3): (1) zirconium oxide, (2) titanium, and (3) at least one element selected from the group consisting of phosphorus, selenium, boron, and silicon... upon excitation by ultraviolet light at a wavelength of 300 nm or less, exhibits fluorescence at a wavelength of 400 nm to 600 nm

Methodology Applied
Scientific EffectFluorescence: Fluorescence

Data Source

PatentEP3006540B1Phosphor and method for producing same
Publication Date: 2018.03.07 DAIICHI KIGENSO KAGAKU KOGYO CO LTD
  • EP3006540B1 patent drawingFigure 1~2
  • EP3006540B1 patent drawingFigure 3~4
  • EP3006540B1 patent drawingFigure 5~6

AI summary

The object of the present invention is to provide an oxide-based phosphor comprising elements other than rare earth elements as light-emitting elements, with low material costs, while achieving high luminous efficacy. The means for achieving the object is a phosphor comprising the following (1) to (3): (1) zirconium oxide, (2) titanium , and (3) at least one element selected from the group consisting of phosphorus, selenium, boron, and silicon.