In precision manufacturing sectors such as optical displays, thin-film anti-reflection, and fiber optic communications, refractive index control is a critical determinant of device performance. For applications requiring a lower refractive index alongside high transparency, good processability, and sufficient hardness, material selection often involves trade-offs across multiple performance dimensions. NM-1345 is a fluorine-free, low-refractive-index UV nano sol that offers a viable technical pathway for addressing these requirements.
Product Technology Overview
The core technical feature of NM-1345 lies in the coupling of multifunctional acrylates with specially structured hollow silica particles. Hollow silica nanoparticles contain enclosed air voids within their structure. Since air has a refractive index of approximately 1.0, this structural design effectively lowers the overall refractive index of the material. Compared with conventional solid silica nanoparticles (refractive index approximately 1.46), the hollow structure enables NM-1345 to achieve a significantly lower refractive index level.
Additionally, the product is fluorine-free, avoiding the compatibility issues or additional cost burdens that fluorinated materials may introduce in certain systems. The multifunctional acrylate serves as the film-forming resin matrix, providing rapid UV curing response and a high crosslinking density, which in turn imparts good hardness to the cured coating.
Key Performance Characteristics
From an application perspective, NM-1345 exhibits several notable performance attributes:
Low Refractive Index. Through the introduction of hollow silica, the effective refractive index of the material is significantly reduced. This characteristic makes it suitable for anti-reflective coatings and anti-reflection film systems-in the theoretical design of single-layer anti-reflective coatings, the optimal refractive index range is approximately 1.22–1.25, a range that the hollow silica approach can effectively match.
High Transparency and Low Haze. The nanoscale particle size of the hollow silica (typically in the tens of nanometers range) is much smaller than the wavelength of visible light (380–780 nm), resulting in minimal scattering of visible light. This allows NM-1345 to maintain high light transmittance and low haze after film formation, meeting the stringent clarity requirements of optical display film materials.
Low Viscosity and Good Processability. Low viscosity means the product disperses and processes easily in coating formulations, accommodating various industrial coating methods such as roll-to-roll coating, spin coating, and slot-die coating. This characteristic has practical significance for large-scale continuous production.
Fast Curing and High Hardness. The multifunctional acrylate system gives NM-1345 a rapid UV curing response, allowing curing at relatively low energy doses. The crosslinked network formed after curing provides high coating hardness, contributing to enhanced wear and scratch resistance.
Primary Application Areas
NM-1345's applications span multiple optics-related fields:
Anti-Reflective Coatings and Thin-Film Anti-Reflection. In displays, touchscreens, photovoltaic glass, and other scenarios where surface reflection needs to be reduced and light transmittance increased, NM-1345 can serve as a low-refractive-index layer material. When paired with high-refractive-index layers to form multilayer anti-reflective film systems, it effectively enhances the overall optical efficiency of devices.
Optical Fiber Coating. Fiber coatings require refractive index matching with the fiber core as well as good mechanical protection. NM-1345's low refractive index and fast curing make it suitable for fiber coating and protective layer preparation.
Optical Display Films and Nano-Coatings. In various optical films (such as brightness enhancement films, diffusion films, and polarizer protective films), NM-1345 can be used to adjust the refractive index, hardness, and optical transmittance of surface functional layers.
Adhesive and Coupling Applications. In optical component bonding or optical path coupling, low-refractive-index adhesives help reduce interfacial reflection losses. NM-1345's low refractive index makes it valuable in these scenarios as well.
Formulation Recommendations
According to the product TDS, NM-1345 is recommended for use in combination with low-functionality acrylates. The rationale behind this formulation strategy is that low-functionality acrylates can reduce the shrinkage of the cured system to some extent while improving coating toughness and substrate adhesion. For applications requiring a balance between hardness and flexibility, this formulation approach is worth considering.
Additionally, NM-1345 exhibits good miscibility with various conventional monomers and is compatible with esters, ketones, and aromatic hydrocarbon solvents. In terms of resin systems, it blends well with polyester, epoxy, polyurethane, and acrylate resins. This formulation flexibility provides engineers with room for adjustment across different systems.
Summary
NM-1345 Low-Refractive-Index UV Nano Sol achieves a balanced combination of low refractive index, high transparency, low haze, fast curing, and high hardness through the coupling of hollow silica with multifunctional acrylates. Its fluorine-free nature and good formulation compatibility further broaden its application boundaries. For material selection in anti-reflective coatings, thin-film anti-reflection, optical fiber coating, and optical display film materials, NM-1345 represents a technical solution worth considering. In practical applications, formulation optimization based on specific process conditions and performance requirements is recommended to fully leverage the product's technical advantages.