In the automotive lighting industry, the main considerations for selecting lens materials are light transmittance, high temperature resistance and aging resistance, and service life cycle. Optical grade plastic lenses for car lights generally use optical grade PMMA, optical grade PC and other materials. The advantages of optical grade plastics are: simple technology and low production cost.

The disadvantage is that the high temperature resistance and aging resistance are relatively weak. PMMA generally has a temperature resistance of no more than 90 ℃ (heat deformation temperature of 105 ℃), while PC has a temperature resistance of no more than 120 ℃ (heat deformation temperature of 135 ℃).

The characteristics of glass lenses are opposite to those of plastic lenses. Glass lenses have high transmittance and good high temperature resistance, but their high density will increase the weight of the headlight lens module, which is not in line with the lightweight goals of the automotive industry. Due to the special state of the glass body after softening, it is not easy to achieve large-scale production. In addition, the mold cost is high, the processing cycle is long, the accuracy is difficult to control, and it is brittle, especially for lenses with large thickness changes. Unexpected bursting is unpredictable and unsolvable.

With the current achievable improvement process, the strength of glass can only be enhanced through coating or tempering treatment. However, after these treatments, the transmittance of glass lenses will be reduced, which also increases costs.

Silicone lenses combine the advantages of the above lenses and exhibit excellent performance in terms of transmittance, molding difficulty, and aging resistance compared to traditional glass and plastic lenses.

RTV two-component silicone thermal conductive silicone rubber, plz check MY LSR 3760