Ultraviolet light blocking optically clear adhesives for foldable displays via highly efficient visible-light curing.

Area of Science:

• Materials Science
• Polymer Chemistry
• Optoelectronics

Background:

• Foldable smartphones require UV-blocking optically clear adhesives (OCAs) for reduced power consumption.
• Incorporating UV-blocking agents into OCAs hinders traditional UV-curing methods.
• Existing visible-light curing techniques for UV-blocking OCAs are too slow for commercialization.

Purpose of the Study:

• To develop a highly efficient photo-initiating system (PIS) for rapid visible-light curing of UV-blocking OCAs.
• To overcome the limitations of slow curing speeds in previous visible-light curing methods.
• To enable the commercial viability of UV-blocking OCAs for foldable OLED displays.

Main Methods:

• Selection of a photocatalyst (PC) to minimize unwanted electron and energy transfer to UV-blocking agents.
• Design of novel co-initiators for enhanced electron transfer and faster PC regeneration.
• Utilizing a visible-light curing technique with the optimized PIS.

Main Results:

• Achieved a tenfold increase in the production speed of UV-blocking OCAs.
• Maintained the critical properties of OCAs: UV protection, optical transparency, and flexibility.
• Demonstrated effective UV protection when the developed OCA was applied to OLED devices.

Conclusions:

• The novel PIS significantly accelerates the production of UV-blocking OCAs using visible light.
• This advancement addresses the commercialization barrier posed by slow curing speeds.
• The developed UV-blocking OCA shows promise for protecting various smart devices beyond foldable smartphones.