Glass Ceramic Composition for UV-Resistant Transparent Strengthening
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Chemically strengthened glass and glass ceramic materials face issues with reduced transparency and UV resistance when exposed to ultraviolet light, particularly in the shorter wavelength range, which affects their performance in display applications.
Innovation Solution
A glass ceramic composition comprising 65-75% SiO2, 3-6% Al2O3, 15-25% Li2O, and 0.01-0.5% HfO2, with optional inclusion of β-spodumene, petalite, or eucryptite crystals, enhances transparency and UV resistance by minimizing ultraviolet-induced absorption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If glass ceramic is used to improve hardness and scratch resistance, then strength is improved, but transparency deteriorates when compared with amorphous glass
Solution Approach 1:
The patent applies local quality by creating specific crystal phases (β-spodumene, petalite, or eucryptite) with controlled size and distribution within the glass ceramic matrix. By controlling crystal size to be small and distributing them uniformly, the material achieves both the desired hardness from crystallization and maintained transparency by minimizing light scattering effects.
Solution Approach 2:
The patent employs parameter changes by precisely controlling composition parameters (SiO2: 65-75 mol%, Al2O3: 3-6 mol%, Li2O: 15-25 mol%) and heat treatment parameters to achieve specific crystal phases. By adjusting these parameters, the glass ceramic achieves optimal balance between hardness (from crystal formation) and transparency (by controlling crystal size and distribution).
2Ease of manufacture
If ultraviolet light irradiation is used to remove organic substances and modify surface, then cleaning and surface modification are improved, but transparency in particular wavelength range deteriorates
Solution Approach 1:
The patent applies preliminary action by incorporating UV-resistant components (HfO2, TiO2, ZrO2) into the glass ceramic composition before manufacturing. This preliminary incorporation of UV-resistant materials prevents solarization and maintains transparency even after subsequent UV irradiation treatments during manufacturing processes, eliminating the need to choose between surface modification and transparency.
Solution Approach 2:
The patent converts the potentially harmful effect of UV irradiation (which can cause solarization and reduce transparency) into a beneficial process by using controlled UV irradiation during manufacturing to achieve surface modification while the UV-resistant composition prevents damage. The UV irradiation that would normally be harmful becomes a useful surface treatment step.
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 glass ceramic achieves high transparency and UV resistance, maintaining light transmittance above 85% in the 380-780 nm range and exhibiting improved chemical strengthening properties with a surface compressive stress of 100 MPa or more and a depth of 100 μm or more.
Implementation Method 1
including, in mol % in terms of oxides: 0.01-0.5% of HfO2... forming local regions with high HfO2 concentration to enhance UV resistance
Implementation Method 2
Glass ceramic is glass including crystals precipitated therein
Implementation Method 3
bringing the glass into contact with molten salt containing alkali meal ions and thereby causing ion exchange between alkali meal ions in the glass and the alkali meal ions in the molten salt
Data Source
AI summary
The present invention relates to a glass ceramic including crystals, and including, in mol % in terms of oxides: 65-75% of SiO2; 3-6% of Al2O3; 15-25% of Li2O; 0.2-4% of P2O5; 0.5-5% of ZrO2; and 0.01-0.5% of HfO2, in which the crystals include one or more kinds of crystals selected from the group consisting of β-spodumene crystals, petalite crystals, and eucryptite crystals.