Thanks to their compact size and high compatibility, SMD LEDs have become the mainstream light source in lighting and electronics. The optical properties of encapsulants directly determine the luminous efficiency of SMD LEDs. A high-refractive-index phenyl-based LED encapsulant, specially developed for SMD LEDs, features a dual optical advantage of 1.54 high refractive index and 92% high light transmittance. Combined with suitable viscosity and mechanical properties for SMD packaging, it has become an excellent choice for SMD LED encapsulation, maximizing the luminous efficiency of miniaturized light sources. Its core competitiveness lies in the high-refractive-index optical performance designed exclusively for SMD LEDs. The 1.54 refractive index perfectly matches the light-emitting characteristics of SMD LED chips, allowing light to propagate at the optimal angle through the adhesive and minimizing refractive loss at the source. This solves the problem of luminous efficiency waste caused by refractive index mismatch in traditional encapsulants. The 92% high light transmittance further enhances performance, enabling most light to pass through easily. The encapsulated SMD LEDs feature high brightness and uniform light emission, ensuring excellent performance even in compact SMD structures. Its processability and compatibility also meet the production requirements of SMD LEDs. With a base viscosity of 4500 mPa·s for Part A and 6000 mPa·s for Part B, the 1:1 weight ratio mixture provides a moderate viscosity of 6000 mPa·s. Its flowability is ideal for precision SMD LED packaging, accurately filling miniaturized packaging gaps without glue overflow or insufficient filling, perfectly matching the precision operations of SMD production lines. The curing conditions of 100℃/1h + 150℃/3h are consistent with standard industrial curing processes, allowing easy integration into existing production lines without additional equipment adjustments. The cured adhesive exhibits excellent mechanical properties. With a Shore D hardness of 52, it balances rigidity and toughness, adapting to the miniaturized structure of SMD LEDs without damage from minor impacts. Its tensile strength of 8 MPa far exceeds that of ordinary encapsulants, firmly protecting the LED chips and brackets and preventing component loosening during transportation and installation. This encapsulant is widely applicable to LED panel lights, flexible light strips for residential lighting, SMD lamps for automotive electronics, and backlight SMD LEDs for consumer electronics, providing both outstanding luminous efficiency and stability for various SMD light sources.