Development Trend of Flame Retardant Materials for TV Shells

Jan. 01, 70

1. The initial development of plastics for TV housings (mainstream material: ABS)

In the early development of TV housing materials, ABS materials were mostly used. ABS has good comprehensive properties. The material has high mechanical strength, low shrinkage, and good insulating materials. Its electrical properties do not change greatly with changes in temperature and humidity. Like most organic polymer materials, ABS resin is flammable The material has a low Limit Oxygen Index (LOI) (18.3%-18.8%) and belongs to the HB level according to the UL94 standard. ABS burns fast when it catches fire, and emits a lot of poisonous gas and black smoke, which is not conducive to practical application. Therefore, in the past 50 years, people have conducted a lot of research and development on flame-retardant ABS. Flame-retardant ABS is mainly used in the housing of electronic and electrical equipment such as telephones and computers (required to meet UL94 V-0 or 5-V standards).

According to different requirements, different flame-retardant ABS can be selected for the housing of the LCD TV. For example, high-gloss spray-free products exported to Europe usually use high-gloss halogen-free flame-retardant PC/ABS alloys, which can meet the requirements of WEEE and the environmental protection requirements of European TCO’03. For ordinary products without spraying, large-size TVs usually use brominated epoxy resin flame-retardant ABS resin to meet the processing requirements of the product. For small-sized products, tetrabromobisphenol A environmentally friendly flame-retardant ABS resin is usually used to save costs. For export to the United States, or other internal parts such as LCD TV brackets and electrical boxes that do not have the relevant requirements of the ROHS directive, decabromodiphenyl ether flame retardant ABS resin can usually be used.

2. Medium-term development of plastics for TV housings (mainstream material: HIPS)

Since the 1980s, HIPS has been used instead of ABS. HIPS has good fluidity, and the molding shrinkage rate is about 0.5%, which is close to ABS. HIPS can be molded with ABS molds. However, the surface gloss of HIPS is not as good as ABS, but in recent years, high-gloss HIPS has been developed abroad. In terms of cost, the advantage of HIPS is that the price is 20% lower than that of ABS, and HIPS has become a better choice for TV housing materials. However, HIPS is flammable and must be flame-retardant modified as a TV shell to reach UL94 flame-retardant V0 level.

3. Late development of plastics for TV housings (mainstream material: PP)

In the 21st century, with the continuous development of various cost-effective materials, the selection of TV housings will gradually shift to low cost, lighter weight and higher cost performance. Flame-retardant modified PP is expected to become the third-generation material for TV housing selection. As one of the four general plastic materials, PP has excellent comprehensive properties, good chemical stability, heat resistance, good molding and processing properties and relatively low prices.

222-阻燃PP(黑色粒子)

However, PP material is flammable, has poor low-temperature impact resistance, and has a large shrinkage rate; through flame-retardant modification, PP products can reach UL94V-0 level, and can withstand 650℃ or even 750℃ glow wire without ignition. Through filling modification, It can reduce molding shrinkage and warpage deformation, improve the rigidity, surface hardness and heat resistance of molded products, and the low-temperature impact resistance of PP materials can also be achieved through modification, so as to meet the requirements of TV housing selection, heat resistance and resistance. Fire resistance, voltage resistance, high and low temperature impact resistance and high fluidity requirements.