LED, as the fourth generation lighting body after incandescent lamp, fluorescent lamp and energy-saving lamp, has a series of advantages, such as high luminous efficiency, low power consumption, long service life, high reliability, strong controllability and green energy saving, and has been widely used in home, city, industry, automobile, aerospace and other fields.
LED can be seen everywhere from indoor lighting to outdoor lighting, from urban landscape lighting to sign lighting, from agricultural lighting to industrial lighting.
Adhesive seal as LED lighting products, such as the ball bubble lamp, project-light lamp, T8 tubes, etc.) an integral part of the production and processing process, generally USES the silicone sealant as a solution, silicone sealant improper selection, will give the application of LED lighting products, safe and reliable in performance, service life, etc. Bring huge hidden trouble. Therefore, how to choose silicone sealant in LED lighting products has been the focus of the industry.
In general, the main performance requirements of silicone sealant for LED lighting include: low volatile content, excellent yellowing resistance, neutral non-corrosion, halogen and sulfur free, excellent adhesion and wide adaptability to the substrate. The specific analysis is as follows:
1) low volatile: silicone sealant if released in the process of solidification of high content of organic small molecules, will be on the surface of the lamp body occurred in chimney that seal and form fog state, thus affecting the lamp body and color temperature, and low volatility of the silicone sealant can ensure the LED lighting product the lamp body is not affected by internal of fog.
2) excellent yellowing resistance: LED lighting products have high requirements on the color change of silicone sealant. In the long term of use, the excellent yellowing resistance of silicone sealant can ensure the normal appearance of LED lighting products.
3) neutral non-corrosive: LED lighting product to use most of the chimney and tubes are low cost, high toughness and long service life of PC material (PC material acid-proof alkali), using alkaline silicone sealant can lead to a PC material corrosion cracking, thus shortening the service life of lamps and lanterns, therefore, LED lighting products use silicone sealant for neutral non-corrosive.
4) no halogen or sulfur: the presence of halogen and sulfur will lead to the halogenation and blackening of the silver support of LED lamp beads, which will lead to large fluctuations in the current of LED lamp beads, affecting the light efficiency and color temperature of LED lamp beads, and even cause dead lights in serious cases. Therefore, silicone sealant used in LED lighting products requires halogen and sulfur free.
5) excellent adhesion and widely adaptability of base material: LED lighting products of various adhesive materials, including PC, PBT, PET, ABS, PA, and these materials and glass fiber composite materials, excellent adhesion and widely adaptability of base material can ensure the silicone sealant for LED lighting products that may occur in a variety of substrate bonding, to guarantees the security and stability of products.
In the traditional LED lighting industry, considering the main performance requirements of silicone sealant used for LED lighting, the titanate catalyzed methanol type silicone sealant is generally selected as the solution in the industry. However, with the continuous upgrading of production technology, production materials and intelligent production in the field of LED lighting adhesive, the traditional titanate system silicone sealant is increasingly unable to meet the production requirements of LED lighting products, and its performance defects mainly include the following three points:
1) slow curing speed and long time to form adhesive strength: the curing speed of silicone sealant and the time required to produce certain adhesive strength have an important impact on the production efficiency of LED lighting products. If the curing speed is slow and the time required to produce certain adhesive strength is too long, the production efficiency of LED lighting products will be reduced. Traditional system of titanate silicone sealant crosslinking curing need to rely on moisture in the air, moisture diffusion into the rubber, it is difficult for 24 hours curing depth of about 2 ~ 3 mm, so as to achieve the best performance of adhesive sealant or even need to use a few days time, this makes the assembly of LED lighting products need seven or eight hours before packaging carrying, seriously affected the manufacturers continuous production efficiency.
2) yellowing resistance poor: traditional system of titanate silicone sealant are mostly using isopropyl titanate and acetyl ethyl acetate synthesis of titanium or secondary titanium chelate as catalyst, the catalyst synthesis process of by-products easily with other materials in the LED lighting product component produces chemical reaction, cause silicone sealant and PC blister yellowing phenomenon, adverse effects on the appearance of the LED lighting products.
3) lack of extensive bonding and durability: LED lighting products are involved in the actual production of a wide variety of bonding materials, silicone sealant only has a wide bonding property, can play a bonding and fixing effect on various materials used in the production and processing of LED lighting products. In addition, silicone sealant also needs to have a good adhesive durability, to ensure that LED lighting products in a variety of harsh use environment will not fail to adhesive. However, the traditional titanate system silicone sealant has poor adaptability and poor adhesion durability to the substrate used in the production and processing of some LED lighting products, which cannot meet the needs of the LED lighting industry today.
Guangzhou baiyun chemical industry co., LTD., as the leading enterprise of silicone sealant in China, has been committed to the research and development of silicone sealant for LED lighting.
Demand change, beyond the requirements, baiyun chemical constantly developed suitable for LED lighting products of silicone sealant series products, this series of products with the LED lighting for the advantages of the silicone sealant, namely: good yellowing resistance, low volatile, neutral, non-corrosive, halogen-free, sweet, extensive adhesion, good bonding durability, excellent comprehensive performance, and improve the shortcomings of traditional sealant, new baiyun brand silicone sealant compared to the traditional silicone sealant curing speed, resistance to yellowing, and strengthen the universality and bonding durability, for the adhesive sealing reliability of LED lighting provides a powerful guarantee.