Benzotriazole UV Absorber for Blue Light Blocking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current optical materials fail to effectively block harmful blue light around 420 nm, leading to eye fatigue and potential damage, and often result in yellowing or opacity issues when using ultraviolet absorbers, compromising transparency and optical properties.
Innovation Solution
An optical material containing 2-(2-hydroxy-3-t-butyl-5-methylphenyl)-chlorobenzotriazole as an ultraviolet absorber, combined with polysulfide or polythiol compounds, which achieves specific light transmittance characteristics at 410, 420, and 440 nm wavelengths, ensuring a colorless and transparent appearance while providing effective blue light blocking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If an ultraviolet absorber is used to block harmful light, then light transmittance at 410 nm is reduced, but the resin turns yellow or the ultraviolet absorber precipitates causing opacity
Solution Approach 1:
The patent changes the chemical parameters of the ultraviolet absorber by specifying a particular benzotriazole derivative with controlled molecular structure and concentration range (0.01-5 wt%). This parameter optimization allows the absorber to effectively block harmful light at 410 nm while maintaining sufficient transparency at 440 nm, preventing both yellowing and precipitation issues
Solution Approach 2:
The patent creates a composite optical material system combining the base resin with a specifically formulated ultraviolet absorber (benzotriazole derivative) and optional auxiliary agents. This composite approach allows the absorber to function effectively without compromising the overall optical properties, as the components work synergistically to achieve both protection and transparency
2Object-affected harmful factors
If conventional ultraviolet absorbers are added to achieve blue light blocking, then light transmittance at 420 nm is reduced, but the material becomes opaque or yellowed
Solution Approach 1:
The patent optimizes the absorption parameters by selecting a benzotriazole derivative with specific spectral characteristics that provides strong absorption at 420 nm while maintaining transmittance at 440 nm. The concentration is precisely controlled within 0.01-5 wt% to achieve the desired balance between blue light blocking and overall transparency
Solution Approach 2:
The patent applies partial action by targeting specific wavelength ranges rather than blocking all short-wavelength light. The ultraviolet absorber is designed to selectively block harmful wavelengths (410-420 nm) while allowing beneficial wavelengths (440 nm and above) to pass through, achieving protection without excessive light blocking that would cause opacity
3Object-affected harmful factors
If iron oxide particles are added to block ultraviolet light, then ultraviolet transmittance is reduced, but the molded product is colored
Solution Approach 1:
The patent uses an organic benzotriazole derivative as an intermediary substance that absorbs ultraviolet light through molecular electronic transitions rather than through particle scattering like iron oxide. This intermediary approach provides UV blocking functionality while maintaining the transparency and colorless appearance of the base resin, avoiding the discoloration problem caused by inorganic particles
4Reliability
If polycarbonate resin is used for transparency, then optical properties such as refractive index need improvement
Solution Approach 1:
The patent makes the optical material multi-functional by combining the base polycarbonate resin (which provides transparency and impact resistance) with the ultraviolet absorber system (which provides blue light blocking and UV protection). This universal material system simultaneously achieves multiple functions: transparency, mechanical strength, and optical protection, eliminating the need for separate functional layers or complex multi-component systems
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 material effectively blocks harmful blue light, preventing eye fatigue and maintaining transparency and optical quality, making it suitable for plastic spectacle lenses and other applications.
Implementation Method 1
an ultraviolet absorber (a) comprised of 2-(2-hydroxy-3-t-butyl-5-methylphenyl)-chlorobenzotriazole... a light transmittance of the optical material having a thickness of 2 mm satisfies the following characteristics (1) a light transmittance at a wavelength of 410 nm is equal to or less than 10%, (2) a light transmittance at a wavelength of 420 nm is equal to or less than 70%
Data Source
Figure 1~2
AI summary
The optical material of the present invention contains one or more kinds of ultraviolet absorber (a) having a maximum absorption peak within a range of equal to or greater than 350 nm and equal to or less than 370 nm, in which a light transmittance of the optical material having a thickness of 2 mm satisfies the following characteristics (1) to (3), (1) a light transmittance at a wavelength of 410 nm is equal to or less than 10%, (2) a light transmittance at a wavelength of 420 nm is equal to or less than 70%, and (3) a light transmittance at a wavelength of 440 nm is equal to or greater than 80%.