I.Strict selection of raw materials
A): PET & ITO Layer
Ultra-flat PET film:
Lumesen only uses TOP-Grade optical-grade PET with a thickness tolerance of ±1%, surface roughness Ra≤0.1μm, and transmittance＞87%~95%.
Nano-level conductive materials:
Indium tin oxide (ITO): Multilayer composite films (such as ITO+AZO+ITO) are plated by magnetron sputtering, with a square resistance of ≤15Ω/□, transmittance＞88%, and anti-bending performance is improved by 3 times (can withstand 100,000 folding tests).
Alternatives: Nano silver wire (wire diameter <20nm) or single-walled carbon nanotube (SWCNT) conductive layer, suitable for flexible curved scenes, conductivity＞10⁶ S/m.
B): High-end PDLC slurry
Liquid crystal material:
Lumesen Using chiral nematic liquid crystal or fluorinated liquid crystal (such as Merck E7 series improved type), the response speed is increased to ≤50ms, and the operating temperature range is extended to -40℃~85℃ (0℃~60℃ for ordinary products).
Polymer system:
Lumesen Using UV-curable acrylate prepolymer (such as Sartomer CN2200), adding nano-silicon dioxide (particle size 50nm, dispersion ≤5%) to enhance mechanical properties, glass transition temperature (Tg)＞120℃.
Additive upgrade:
Adding light stabilizer (HALS) and antioxidant (hindered phenol), the UV resistance time is ≥5000 hours (about 2000 hours for ordinary products).
II.Ultra-precision coating and coating process
A): Vacuum magnetron sputtering coating
Multi-target co-sputtering:
In an environment with a vacuum degree of <10⁻³ Pa, ITO target and aluminum oxide (Al₂O₃) target are sputtered in sequence to form an ITO/Al₂O₃/ITO sandwich structure, which improves the scratch resistance of the conductive layer (hardness up to 4H).
Online detection:
Equipped with a laser thickness gauge (accuracy ±1nm) and a four-probe tester (resolution 0.1Ω/□), real-time monitoring of film uniformity, local thickness deviation ≤2%.
B): Nano-scale slurry coating
Slit coating + vacuum drying:
Lumesen Use a micro-gravure coating head (accuracy ±0.5μm) to coat PDLC slurry in a vacuum environment (pressure ≤50kPa) to avoid bubble mixing. The coating thickness is controlled at 20±0.5μm, and the surface density deviation is ≤1.5%.
Gradient temperature pre-curing:
Temperature control in three stages (40℃→60℃→80℃, 10 minutes each) to gradually volatilize the solvent (such as cyclohexanone) and form a stress-free liquid crystal-polymer precursor structure.
III.Vacuum lamination and UV curing upgrade
A): Vacuum hot pressing lamination
Dual chamber vacuum laminator:
The first layer (lower electrode + PDLC layer) and the second layer (upper electrode + protective layer) are preheated in a double-station vacuum chamber (80℃, 5 minutes), and then laminated through a precision alignment system (accuracy ±5μm), and finally pressurized for 30 minutes under **0.01MPa vacuum degree + 120℃** to ensure that there are no micro bubbles between the layers.
B): UV curing system upgrade
Pulse UV curing:
Lumesen Using LED-UV pulse light source (peak light intensity > 20W/cm², wavelength 365±5nm), irradiation time 50~100ms, instant curing, avoiding polarization drift of liquid crystal due to long-term heating.
Nitrogen protection curing environment:
High-purity nitrogen (purity 99.999%) is introduced into the curing chamber, and the oxygen content is <10ppm, which inhibits the oxidation and yellowing of the polymer and ensures that the long-term transmittance attenuation is <3% (the attenuation of ordinary products is about 8%).
IV.Precision post-processing and strict testing
A): Laser cutting and edge sealing
Picosecond laser cutting:
Lumesen Using ultra-short pulse laser (pulse width <10ps) to cut the film material, the edge heat-affected zone is <10μm, avoiding edge delamination caused by traditional mechanical cutting.
Nano coating edge sealing:
The silicon dioxide (SiO₂) coating is deposited on the edge by vapor deposition (CVD) process with a thickness of 200~500nm to form a moisture-proof and oxygen-proof "molecular-level sealing layer". The performance retention rate after the heat and humidity test (85℃/85% RH, 1000 hours) is >95%.
B): Full process optical inspection
Laser speckle detection:
The film surface is irradiated with a 635nm laser beam, and the speckle pattern is captured by a CCD camera. The AI algorithm analyzes the uniformity of the liquid crystal droplet distribution, and the maximum droplet size deviation is allowed to be <5%.
Dynamic response test:
In a -40℃~85℃ temperature box, a high-speed camera (frame rate 1000fps) is used to record the atomization-transparent switching time of the power-on/power-off process, and the response speed fluctuation in the whole temperature range is required to be ≤10%.
Life Accelerated Test:
The xenon lamp aging test chamber (irradiance 1.2kW/m², cycle 120 minutes) was used to simulate a 10-year outdoor environment. After the test, the transmittance decay was <5% and the haze change was <2%.
A): Digital Production Line
Equipped with MES system to monitor the parameters of each process (such as coating thickness, curing light intensity, lamination pressure) in real time, with a data acquisition frequency of 10 times/second. In case of abnormality, it will automatically trigger shutdown and trace the first 100 meters of products.
Visual Inspection Robot:
Equipped with a linear array CCD camera (resolution 1200dpi) and a deep learning algorithm, it can achieve 100% surface defect detection (minimum recognition size 0.1mm), and the rejection rate is ≤0.05%.
B): Key Technology Breakthrough Points
Molecular-level uniformity control: Through nanomaterial dispersion technology and vacuum process, the particle size distribution of liquid crystal droplets is concentrated in 2~3μm (4~6μm for ordinary products), and the optical scattering efficiency is increased by 30%.
Wide temperature range stability: Through fluorinated liquid crystal and high temperature resistant polymer, the optical performance fluctuation in the full temperature range of -40℃~85℃ is less than 5% (the fluctuation of ordinary products is about 15%).
Ability to resist extreme environments: After 100kPa high-pressure water washing and salt spray corrosion (5% NaCl, 1000 hours) tests, the resistance change of the conductive layer is less than 3%, and the interlayer adhesion retention rate is greater than 98%.
Lumesen not only relies on equipment precision and material innovation, but also ensures process stability through the Six Sigma quality management system (DPPM≤50) and ISO 14644-1 Class 5 clean workshop (dust particles ≤3520/m³, ≥0.5μm). This is why LumesenFilm can be applied for scenes with extremely high safety and reliability requirements.
