Optical bonding technology seamlessly bonds the LCD screen to the touch panel by means of aqueous adhesive (LOCA) or optical adhesive (OCA), completely eliminating the air layer, thus reducing light reflection and loss, and significantly improving display clarity and brightness. According to the different adhesive materials used, full lamination technology is mainly divided into OCA (Optical Clear Adhesive) lamination and LOCA (Liquid Optical Clear Adhesive) lamination two kinds.
1. OCA optical
Applicable scene: small-size LCD products.
Advantage:
High production efficiency, uniform thickness of adhesive layer;
No risk of overflow, controllable bonding precision;
No corrosiveness, convenient maintenance.
Limitations:
Yellowing may occur in long-term use;
Easy to produce air bubbles at the poor ink section.
2. LOCA bonding
Applicable scenarios: large-size LCD, curved surface or complex structure lamination.
Advantage:
Strong compatibility with ink thickness, easy to rework.
Limitations:
Longer curing time, affecting production efficiency;
Higher difficulty in controlling the uniformity of the glue.
Advantages of Optical bonding
Display optimization: significant improvement in screen transparency, brightness and contrast;
Dustproof performance: isolate dust, reduce the probability of dust ingress;
Touch experience: reduce air layer interference, more sensitive touch.
Disadvantages of Optical bonding
High process complexity: lower yield rate, high equipment investment cost;
Difficulty in maintenance: high difficulty in reworking after glue bonding;
Glue limitations: high OCA cost, low LOCA curing efficiency.