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- LE-8011U | UV-Resistant Clear Epoxy Resin
LE-8011U | UV-Resistant Clear Epoxy Resin
- High thermal stability with a Tg> 160°C
- Strong resistance to UV degradation
- High light transmittance
Product Description
OPTOLINQ LE-8011U is an epoxy resin specifically designed for optoelectronic device packaging. This resin exhibits superior thermal stability and excellent UV stability, ensuring that devices can withstand high temperatures and ultraviolet light exposure without degradation.
Upon curing, OPTOLINQ LE-8011U forms robust cross-linked networks, providing strong adhesion and maintaining airtight seals. These properties make LE-8011U an ideal high-performance solution for demanding optoelectronic packaging applications. LE-8011U can be dyed depending on the customer's operating wavelength requirement.
Key Features
- Designed for Optoelectronic Device Packaging: effectively seals and protects optoelectronic components.
- Superior Thermal Stability: LE-8011U can withstand high temperatures without degrading.
- Excellent UV Stability: Resistant to damage and degradation from exposure to ultraviolet light.
- High Optical Clarity: Delivers exceptional light transmission, critical for optoelectronic device functionality.
- Strong Adhesion: Provides excellent bonding strength to diverse substrates, enhancing package reliability.
- Enhanced Air Tightness: Offers effective barrier properties, minimizing gas permeation and protecting sensitive components.
Available versions
Technical Specifications
| General Properties | |||||||
| Mix Ratio Mix Ratio The amount of a constituent divided by the total amount of all other constituents in a mixture | 100:95 | ||||||
| Pot Life Pot Life Pot life is the amount of time it takes for the viscosity of a material to double (or quadruple for lower viscosity materials) in room temperature after a material is mixed. It is closely related to work life but it is not application dependent, less precise and more of a general indication of how fast a system is going to cure. | 7 hours | ||||||
| Refractive index Refractive index The refractive index determines how much the path of light is bent, or refracted, when entering a material. It is calculated by taking into account the velocity of light in vacuum compared to the velocity of light in the material. The refractive index calculation can be affected by the wavelength of light and the temperature of the material. Even though it is usually reported on standard wavelengths it is advised to check the TDS for the precise test parameters. | 1.51 | ||||||
| Thermal Properties | |||||||
| Glass Transition Temperature (Tg) Glass Transition Temperature (Tg) The glass transition temperature for organic adhesives is a temperature region where the polymers change from glassy and brittle to soft and rubbery. Increasing the temperature further continues the softening process as the viscosity drops too. Temperatures between the glass transition temperature and below the decomposition point of the adhesive are the best region for bonding. The glass-transition temperature Tg of a material characterizes the range of temperatures over which this glass transition occurs. | 140-160 °C | ||||||
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| Mechanical Properties | |||||||
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| Chemical Properties | |||||||
| Moisture absorption | 0.74 % | ||||||
| Curing Conditions | |||||||
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| Physical Properties | |||||||
| Viscosity Viscosity Viscosity is a measurement of a fluid’s resistance to flow. Viscosity is commonly measured in centiPoise (cP). One cP is defined as the viscosity of water and all other viscosities are derived from this base. MPa is another common unit with a 1:1 conversion to cP. A product like honey would have a much higher viscosity -around 10,000 cPs- compared to water. As a result, honey would flow much slower out of a tipped glass than water would. The viscosity of a material can be decreased with an increase in temperature in order to better suit an application | 500-700 mPa.s | ||||||
Additional Information
Key Takeaways
Strong UV Blocking
Essentially non-transmissive below approximately 330 nm at 1.5 mm specimen thickness.
Visible and NIR Stability
Maintains high transmittance in the red and near-infrared region after UV and thermal aging exposure.
Controlled UV and Blue-Edge Absorption
UV and thermal exposure increase absorption mainly in the UV, near-UV, and short-wavelength visible region.
Thickness note: Optical performance is strongly dependent on specimen thickness and optical path length. UV-aging and thermal-aging values reported here are based on a 1.5 mm specimen. Thinner encapsulation sections may show higher short-wavelength transmittance and should be validated under the final package design.
Potential Applications
For packages where visible to near-infrared transmission is required.
For optical modules using red or near-infrared operating windows.
For assemblies where UV blocking is beneficial at the selected encapsulant thickness.
For optical encapsulation where the useful emission range is above the UV and blue region.
OPTOLINQ LE-8011U | Optically Clear UV-Blocking Encapsulant
LE-8011U provides high visible to near-infrared transmittance while showing very low transmission near the tested 313 nm UV exposure wavelength at 1.5 mm thickness.
| Wavelenght | Value | Unit |
|---|---|---|
| 450 nm | 82.96 | % |
| 600 nm | 86.42 | % |
| 700 nm | 87.38 | % |
| 850 nm | 88.28 | % |
| 900 nm | 87.74 | % |
| 950 nm | 85.50 | % |
OPTOLINQ LE-8011U UV Aging Performance
LE-8011U was evaluated after exposure to 313 nm UV radiation at 60°C and 1.2 W/m². The material is essentially non-transmissive near the 313 nm exposure wavelength at 1.5 mm thickness, while maintaining high transmittance above approximately 600 nm after 26 hours of UV exposure.
| Parameter | Test Condition |
|---|---|
| Material | OPTOLINQ LE-8011U |
| Specimen thickness | 1.5 mm |
| UV exposure wavelength | 313 nm |
| Exposure temperature | 60°C |
| Irradiance | 1.2 W/m² |
| Exposure duration | 0 h, 4 h, 26 h |
| Estimated UV dose at 4 h | Approximately 17.3 kJ/m² |
| Estimated UV dose at 26 h | Approximately 112.3 kJ/m² |
Test method note: Data shown are typical results based on spectral transmittance measurements under the stated conditions and are provided for reference only. Actual performance may vary depending on application conditions. Users should perform their own testing to determine suitability for their intended use.
| Spectral Region | Observed LE-8011U Performance After UV Exposure |
|---|---|
| Below approximately 330 nm | Essentially non-transmissive before and after UV exposure at 1.5 mm thickness. |
| 340 to 400 nm | Clear reduction in transmittance with increasing UV exposure time. |
| 400 to 500 nm | Moderate transmittance reduction, strongest near the violet edge. |
| 500 to 600 nm | Minor reduction in transmittance after exposure. |
| Above 600 nm | High optical stability, with transmittance remaining approximately 88 to 90% after 26 hours. |
LE-8011U UV-Region Transmittance Retention
Interpolated values based on measured spectral transmittance data from 0 h, 4 h, and 26 h UV exposure. Optical performance is thickness-dependent and should be revalidated at the final encapsulant thickness.
| Wavelength | 0 h T% | 4 h T% | 26 h T% | 26 h Retention vs 0 h |
|---|---|---|---|---|
| 340 nm | 4.60 | 0.48 | 0.04 | ~1% |
| 350 nm | 19.12 | 4.95 | 2.47 | ~13% |
| 365 nm | 51.95 | 31.17 | 20.33 | ~39% |
| 380 nm | 73.49 | 61.19 | 43.86 | ~60% |
| 390 nm | 79.61 | 70.41 | 54.29 | ~68% |
| 400 nm | 82.41 | 75.52 | 61.00 | ~74% |
LE-8011U Transmission Edge Shift After UV Exposure
| Metric | 0 h | 4 h UV Exposure | 26 h UV Exposure | Change After 26 h |
|---|---|---|---|---|
| 10% transmittance wavelength | ~344.7 nm | ~354.2 nm | ~358.4 nm | +13.7 nm |
| 50% transmittance wavelength | ~364.0 nm | ~373.5 nm | ~385.9 nm | +21.9 nm |
| 80% transmittance wavelength | ~391.4 nm | ~416.4 nm | ~454.7 nm | +63.3 nm |
Under 313 nm UV exposure at 60°C, LE-8011U shows its strongest optical stability in the longer visible and near-infrared region. Above approximately 600 nm, transmittance remains high at around 88 to 90% after 26 hours of exposure.
Below 400 nm, LE-8011U shows a clear reduction in transmittance as UV exposure time increases. At 365 nm, transmittance decreases from approximately 52% before exposure to approximately 20% after 26 hours. At 400 nm, transmittance decreases from approximately 82% to approximately 61% after 26 hours.
This behavior is relevant for applications where reduced UV and blue-edge transmission is desired. LE-8011U should be validated under the final wavelength, specimen thickness, UV dose, temperature, cure condition, and package design before use in applications requiring defined optical performance.
Optical data note: UV-aging values are based on provided LE-8011U spectral transmittance data and interpolated at selected wavelengths for comparison. Results are typical test observations and should be validated under the user’s target wavelength, specimen thickness, optical path length, UV dose, temperature, cure condition, and end-use reliability requirements.
LE-8011U Thermal Aging Performance at 200°C
LE-8011U was evaluated for optical transmittance stability after accelerated constant-temperature exposure at 200°C. Transmittance was measured across 200 to 1000 nm using a 1.5 mm thick specimen at initial condition, after 3 hours, and after 500 hours of thermal aging.
Accelerated aging note: Thermal aging at 200°C represents accelerated constant-temperature stress testing and does not directly equate to service life at lower operating temperatures. Results should be interpreted together with the final operating temperature profile, exposure duration, optical wavelength, thickness, and package design.
Thermal Aging Test Conditions
| Parameter | Condition |
|---|---|
| Material | LE-8011U |
| Exposure type | Constant thermal aging |
| Aging temperature | 200°C |
| Specimen thickness | 1.5 mm |
| Aging duration | 0 h, 3 h, 500 h |
| Measurement range | 200 to 1000 nm |
Optical Transmittance After Thermal Aging
Selected wavelengths are shown for readability. Some values are approximated from adjacent measured points where the exact wavelength was not directly listed.
| Wavelength | Spectral Region | 0 h | 3 h | 500 h | Performance Trend |
|---|---|---|---|---|---|
| 300 nm | Deep UV / UV-B | 0.1% | 0.1% | 0.1% | Remains essentially non-transmissive |
| 350 nm | UV-A | 4.0% | 0.8% | 0.2% | UV transmission further suppressed |
| 365 nm | UV-A | 31.8% | 9.2% | 2.7% | Significant reduction after aging |
| 380 nm | Near-UV / violet edge | 63.7% | 26.1% | 11.1% | Strong edge shift after thermal exposure |
| 400 nm | Violet / visible edge | 77.5% | 43.9% | 25.0% | Short-wavelength visible transmission decreases |
| 450 nm | Blue visible | 82.8% | 68.7% | 55.0% | Moderate reduction |
| 500 nm | Green visible | 84.6% | 79.3% | 72.1% | Partial retention |
| 600 nm | Orange / red visible | 86.5% | 85.8% | 84.0% | High retention |
| 700 nm | Red / NIR edge | 87.9% | 87.9% | 87.5% | Stable |
| 800 nm | NIR | 88.9% | 88.9% | 88.8% | Stable |
| 940 nm | NIR | 89.0% | 89.0% | 89.0% | Stable |
| 1000 nm | NIR | 90.0% | 89.7% | 89.4% | Stable |
Absorption Edge Shift After Thermal Aging
The absorption edge shifts toward longer wavelengths as thermal aging progresses, indicating increased absorption in the UV and short-wavelength visible region.
| Transmittance Threshold | 0 h | 3 h | 500 h | Interpretation |
|---|---|---|---|---|
| 10% T | ~355 nm | ~366 nm | ~379 nm | UV cutoff shifts toward longer wavelengths |
| 50% T | ~373 nm | ~409 nm | ~440 nm | Near-UV and blue-visible transmission decrease |
| 80% T | ~412 nm | ~506 nm | ~551 nm | High-transmission region moves into longer visible wavelengths |
| 88% T | ~710 nm | ~717 nm | ~731 nm | Red to NIR transmittance remains stable |
Under constant thermal aging at 200°C, LE-8011U shows a clear wavelength-dependent change in optical performance. The largest transmittance loss occurs below 400 nm, where the material becomes progressively less transmissive after aging. At 365 nm, transmittance decreases from approximately 31.8% initially to 2.7% after 500 hours, while at 380 nm, it decreases from approximately 63.7% to 11.1%. This indicates increased absorption in the UV and near-UV region after prolonged high-temperature exposure.
From 400 to 500 nm, LE-8011U shows partial transmittance loss, especially near the blue-visible edge. However, from approximately 600 nm onward, the material retains high optical transmission. After 500 hours at 200°C, transmittance remains around 84% at 600 nm and approximately 87% to 89% from 700 to 1000 nm. This demonstrates retention in the red and near-infrared regions under the stated test conditions.
This behavior is relevant for optical applications where long-wavelength visible or near-infrared transmission is required during elevated-temperature exposure. For applications that require sustained UV, near-UV, or blue-visible transmission, validation should be performed using the actual operating wavelength, exposure temperature, material thickness, and aging duration.
OPTOLINQ LE-8011U Premixed Properties
| Property | Part A | Part B |
|---|---|---|
| Appearance | Clear to light yellow | Clear to light yellow |
| Shelf Life at 25°C | 12 months | 12 months |
| Specific Gravity | 1.06 | 0.90 |
Processing Instructions
- Mix components A and B in a 100:95 weight ratio and stir uniformly. Ensure that the mixture is uniform and free from streaks or unevenness.
- Defoam the mixture under vacuum conditions for 5 minutes.
- Recommended curing condition: first cure at 130°C for 1 hour, then post-cure at 150°C for 4 hours.
The curing conditions provided are recommended guidelines based on typical laboratory results. Actual curing parameters should be defined and validated by the user to ensure compatibility with specific materials, part geometries, and end-use requirements. It is the user’s responsibility to optimize and confirm curing conditions that meet their performance and quality standards.
Storage and Handling
The uncured resin can be cleaned with acetone or a suitable cleaning agent. Water should not be used as the cleaning agent.
Store in a cold, dry, and clean environment between 10°C and 30°C with relative humidity below 70%. Keep away from direct sunlight and outdoor storage conditions. Under proper storage conditions, unopened Part A and Part B have a shelf life of 12 months.