If you plan to purchase a batch of silicone rubber materials for the LED lighting production line, understanding the relevant knowledge of silicone rubber in LED lighting applications can help you select the appropriate silicone rubber products and avoid incorrect purchases.
This article will introduce the advantages of silicone rubber and its applications in different LED lighting fields.
Why Silicone Rubber Is the Ideal Material for LED Lights?
Although LEDs are highly energy efficient, a portion of electrical energy is still converted into heat when in use by your customers. Effective thermal management is required to maintain lumen output and service life.
Therefore, in order to ensure that the LED lighting system operates normally and to prevent downtime and maintenance costs due to failures, choosing the right materials is very important for you.
In today’s elastomer market, there are numerous materials you can choose from. The following is a simple comparison table of silicone rubber with other common optical materials.
| Performance Index | Silicone Rubber | Epoxy | PC / PMMA (Polycarbonate / Acrylic) |
| Heat Resistance | Excellent | Average | Poor (Prone to softening under high temperature) |
| UV Resistance / Anti-Yellowing Performance | Excellent | Poor | Poor |
| Light Transmittance | Excellent (up to 90% – 95%) | Good | Excellent |
| Hardness and Rigidity | Good (Elastic) | Excellent (High Hardness) | Excellent (High Hardness) |
| Flexibility and Impact Resistance | Excellent | Poor (Brittle) | Average |
| Sealing Performance | Excellent | Average | Not Applicable |
However, silicone rubber has several advantages and is suitable for the use of LED lights. The specific performance advantages are as follows, and you can refer to them:
High Temperature Resistance
Silicone rubber has a wide temperature tolerance range, capable of being used in an environment ranging from -40°C to +230°C. Its outstanding high-temperature resistance perfectly matches the requirements of your produced LED lights.
Because the diodes of LED lights generate heat and create a high-temperature environment, usually from +80°C to +150°C, depending on the power. And the temperature resistance of silicone rubber enables it to work normally under such environmental temperatures. This allows your customers to use it for a long time and ensures the quality of your products.
Optical Properties
Optical-grade liquid silicone rubber (LSR) has a transmittance of up to 90% – 95% in the visible light range (380 – 780nm). Although it cannot match the optical clarity of premium glass in all applications, it can still achieve uniform light diffusion, ensuring that your customers will hardly notice any significant impact during daily use.
If you use the optical-grade liquid silicone rubber with a high refractive index (RI) formula, it can effectively reduce light loss in the produced LED lights, improve the light output efficiency, and gain a good brand reputation.
Aging Resistance and UV Resistance
Silicone rubber is resistant to aging, heat and ultraviolet radiation. Even if your customers use it for a long time and it is exposed to heat or ultraviolet radiation, the rate of yellowing and color change is very slow. The light transmittance will not decline and the transparency can remain stable.
If your LED lighting equipment is to be used in outdoor environments, such as outdoor lighting conditions and electrical enclosures, the anti-aging property of silicone rubber also protects the LED lights, preventing erosion and damage caused by wind, rain and sunlight.
Waterproof Performance and Low Compression Set
The waterproof property and compression permanent deformation resistance of silicone rubber are outstanding. Besides using optical-grade silicone rubber as the lens for LED lights, you can also take advantage of this performance to create protection and sealing.
Due to the low compression set characteristic of silicone rubber, it maintains sealing force and elastic recovery after prolonged compression. You can use it to manufacture sealing rings, gaskets, etc., to reduce the risk of faults caused by water or dust entering the LED lighting fixtures, especially outdoor lighting LED lamps.
Durability and Flexibility
Silicone rubber also possesses durability and flexibility. The flexibility can protect the LED light strips from external influences. When your customers use them in a vibrating environment, silicone materials will help absorb vibration and reduce mechanical stress.
Moreover, if you use silicone rubber to make the light strips, they are suitable for various installation environments, whether on curved surfaces or in narrow spaces.
Durability ensures the quality and lifespan of your LED lights. Silicone rubber is not prone to wear and tear, allowing your customers to use them for a long time, thereby earning a good reputation and expanding the market.
Applications and Product Forms of Silicone Rubber for LED Lights
Compared with traditional lighting technologies, LED lighting has become one of the most popular technologies in the market due to its lower power consumption, longer lifespan, and the ability to emit bright light immediately after being turned on. Silicone rubber is often used in the production of LED lights because of its performance advantages and characteristics.
You can mold silicone rubber into various product forms to meet the needs of different parts of LED lights. And different applications of LED lights have different requirements for silicone rubber.
Daily Indoor Decoration LED Lights
These LED lights can be used for indoor office lighting, cabinet lighting, and LED night lights, among other applications. Customers’ demand for LED lights for indoor office and daily lighting is for uniform and efficient light, eliminating glaring shadows.
Therefore, for your silicone rubber light strips, there are no strict requirements. Just ensure they are suitable for daily use.
For cabinet lighting and LED night lights, there are requirements for the hardness of the silicone rubber casing. A low hardness of the silicone rubber casing makes it easy to install and can adapt to different cabinet sizes and layouts, creating an atmosphere.
Moreover, you can make the silicone rubber shells of the LED night lights in various shapes. The soft shells can avoid the risk of injury to children, making your customers use them with greater peace of mind.
Outdoor and Municipal LED Lights
Outdoor LED lights such as street lights, tunnel lights, garden lights and stadium lighting have high requirements for silicone rubber sealing protection. Outdoor high-power LED lights can make tunnels and nighttime activities brighter, improving visibility and safety.
You can make silicone rubber into sealing pads, gaskets, etc. It is best to help lighting assemblies achieve the protection level of IP66, IP67 or even IP68 to prevent water vapor and dust from entering the internal parts of LED and other components.
Silicone rubber gaskets have flexibility to fit uneven surfaces, providing better protection for the electronic components inside the housing.
Airport Runway LED Lights
Unlike ordinary outdoor lighting, the high-power LED lights used in airports have high requirements for the performance of the products you provide. They need to ensure bright and clear lighting and safe landing of aircraft.
Therefore, your silicone rubber gasket needs to provide reliable sealing, UV resistance, and vibration resistance. It should remain sealed when the LED lights emit heat to prevent fogging that could affect the quality of the light.
Signs and Electronic Display LED Lights
These LED lights are usually turned on throughout the day and night. However, the night effect is better, making the advertisement more prominent. Therefore, there are certain requirements for the heat dissipation and durability of your LED products.
To convey clearer images and information, we suggest that you use silicone gel for encapsulation and packaging, covering the LED chip or the entire circuit board to prevent water ingress and failures.
If your customers need large LED screens, you can seal smaller units. This way, if there are subsequent problems, you can partially replace and repair them, reducing your after-sales expenses.
Offshore Rig LED Lights
If your customers are using LED lights for lighting on oil and gas drilling platforms, these lights are prone to failure due to ozone, ultraviolet rays, salt spray and other environmental factors.
In the face of extreme temperatures, extreme weather conditions and high power requirements, high-performance silicone rubber gaskets can play a role in preventing water and dust.
Automotive LED Lights
Unlike the previous applications, in the automotive industry, LED lights not only require extremely high heat resistance, impact resistance (resistance to stone strikes), and optical accuracy, but also need to be able to withstand the effects of vehicle movement.
You can use silicone rubber foam extrusion materials for thermal isolation and achieve the long-term and stable operation of LED lights.
Silicone diffusers can also be extruded into flexible profiles that can be cut to length and be a major selling point for you. It can be used in vehicle interiors to provide flexible lighting solutions, giving your customers more choices.
FAQ
What Are the Aging Failure Mechanisms of Silicone Rubber in LED Lights?
It is divided into 3 stages. First, the LED light has no obvious light attenuation and its performance is stable. Second, the light attenuation of the silicone rubber gradually increases and the temperature rises accordingly, then it enters the deterioration stage.
If you find that the silicone rubber undergoes yellowing and the light power drops sharply, the product fails. You can remind customers to replace it in advance during the deterioration stage to avoid greater losses.
How to Choose the Hardness (Shore A) of Silicone Rubber for LED Packaging?
If it is for chip scale packaging (CSP) or stress buffer layers, it is recommended to choose low-hardness silicone gel, typically measured on the Shore 00 scale (Shore 00 20–50). For general encapsulation and sealing, choose 30 A – 50 A, which can balance both flexibility and protection.
If you are producing optical lenses and car headlights, then choose high-hardness 60 A – 80 A silicone rubber, which can maintain accuracy and facilitate cutting.
What Are the Core Advantages of Silicone Rubber Compared with Mainstream LED Packaging Materials?
The core advantages of silicone rubber lie in its optical stability, thermal stability and stress release. It has a high light transmittance, strong resistance to UV and yellowing, and can buffer the expansion and contraction stress caused by thermal cycles, protecting the chip.
How Does the Curing Process of Silicone Rubber for LED Packaging Affect Production Yield?
The curing process of silicone rubber involves precise control of factors such as mixing ratio, degassing treatment, and temperature and time. These factors directly affect the light transmittance, hardness, and presence or absence of air bubbles and voids, and are crucial for the production yield.
What Has Become the Mainstream Trend in Silicone Rubber-Related LED Processes?
The molding process that combines the encapsulation material and the lens into one unit is becoming the mainstream, as it simplifies the process and reduces costs.
Final Thoughts
Legensilico is a silicone manufacturer with over 20 years of experience. We can provide you with silicone rubber products suitable for different parts of LED lights. We can also offer customization services, allowing us to incorporate your brand logo. If you are interested in our silicone rubber products, please feel free to contact us at any time.
