Flat-panel TVs side frame forming of new technologies - high-gloss coating-free Seamless Injection Molding (The first part )
In order to meet consumer demand for flat panel displays and aesthetic appearance, but also in order to be more environmentally friendly, using high-gloss spray-free Seamless injection molding technology to produce flat panel displays are increasingly becoming mainstream. The emergence and development of the technology is inseparable from the continuous development of plastic molding technology and innovation, covering a high-gloss plastic materials, high-gloss plastic injection mold, mold temperature and temperature control equipment, and many other aspects.
In recent years, there has been no longer satisfied with the use of flat-panel TV features, the appreciation of its taste and appearance of the green environmental protection have become increasingly demanding. As in the past that the first injection TV chassis, and then spraying methods, not environmental protection, quality is not stable, a number of international and domestic well-known TV makers such as Samsung, Sharp, Changhong, Haier, etc. have abandoned the old method in favor of a new type of molding process - to avoid spraying the high light Seamless injection molding technology. This technology enables flat panel displays a high degree of surface gloss and without weld lines, flow marks and other marks, and shrinkage defects, and no follow-up of the spraying process and thus is extremely beneficial to environmental protection and cost reduction. As the spray-free injection technology, the implementation of the high light can not do without high-gloss plastic materials, high-gloss plastic injection mold, mold temperature and temperature control equipment as well as injection molding machines and injection molding processes work closely with, this article from one of these aspects of the technology described.
High-gloss plastic materials to avoid spraying
To achieve a high optical injection-free spray, first of all need to use high-gloss plastic materials. Properties of the materials for such requirements generally include: the material flow should be higher, so that it can better mold surface replication, reduce shear and improve the weld line; the need for a certain degree of resistance to scratch, which means that the surface hardness is better in general pencil hardness of H or more; materials, better thermal stability, not easy to produce volatile compounds. Especially for the flame-retardant grade material, improve heat resistance and reduce the volatile matter can prevent corrosion and reduce the mold surface forming the white mist; material itself better gloss; should have excellent toughness and a certain rigidity, which can be appliances required drop tests and other functional tests.
At present, to avoid spraying the frame of the injection flat-panel TV production mainly in PMMA / ABS, PC / ABS or high-light ABS. Among them, high-gloss ABS hardness minimum, PMMA / ABS highest hardness, pencil hardness of up to 1H or more (as shown in Figure 1). Highlight PMMA / ABS semi-permeable effect can also be made to achieve more energetic appearance and function of LED-rays. Today, many companies have introduced a PMMA / ABS, such as Samsung Cheil Industries of the BF-0677F, Shanghai Kumho day, as well as Korea's LG Chemical HAM8541 the XG569C so. If you require the use of flame-retardant materials, you can use halogen-free flame retardant PC / ABS, such as the Korea Kumho day HAC8250NH, or the selection of flame-retardant high-gloss ABS, such as Shanghai Kumho day Korea's HFA705G. TV manufacturers can choose according to the products of the different requirements of different types of materials. It is predicted that in the near future, the TV manufacturers will be more inclined to go for the ultra-thin LED TV, high-rigidity enhancing material, such as the Korea Kumho day HCG25X0FR. As this low-profile design to meet the rigid requirements, and can maintain a high light appearance.
