LED material: specific fluorescent powder can not be replaced

White LED with high luminous efficiency, long life, the advantages of energy saving and environmental protection, the green lighting and information display technology has wide application prospects. At present, the commercial white LED core material has the blue light LED chip and the fluorescent powder two kinds, are indispensable. Although there are many alternative technical solutions, but from the development trend, the use of fluorescent powder combined with Blu ray LED chip will be the mainstream production of white LED. Therefore, the phosphor is very important for the LED lighting and LCD industry, and the governments, research institutions and industry have attached great importance to the research and development.

Foreign patent restrictions

At present, acid yellow phosphor aluminum yttrium garnet structure using cerium activated LED to produce white light blue collocation luminous efficiency is best, however due to the serious shortage of phosphor in the red part, resulting in poor color rendering of white LED products, white LED can not use the single fluorescent powder preparation of low color temperature and high color the. This "blue chip powder products as the light source, in the visual feeling too cold; as LCD backlight, display color gamut is narrow, the effect is not good. The "white LED devices made of pink yellow blue chip display index has greatly improved (more than 80), but to get the display index higher (more than 90), it is necessary to add green fluorescent powder.

In the LED phosphor development process, sulfide, sulfur oxide, tungsten acid salts, germanate, arsenate, scandium silicate have been developed and applied, but because these systems exist phosphor excitation stability, low efficiency and high cost shortcomings have not been widely used. At present, yttrium aluminate powder with high luminous efficiency and excellent structure and chemical stability will still play an irreplaceable role, nitride and oxynitride phosphors with its unique structure, excellent luminescent properties and stable performance has become the development and application of key white LED red and green fluorescent powder.

Because our country specialized, the system carries on the development to the LED phosphor powder to start late, the foreign has occupied the advantageous position in the LED phosphor patent aspect. As with yttrium aluminate phosphor phosphor garnet structure is more traditional, because of its short afterglow characteristics in 1960s, has been widely used in flying spot scanner, and the fluorescent powder itself does not exist the problem of patent. And in 1997, Nichia GaN chip with collocation of the fluorescent powder for white light and apply for a patent. Again in the liquid crystal backlight white light LED widely used in the silicate system materials are widely used in the early long afterglow material, but later in the LED with silicate phosphor patent layout, and abroad in the front. After years of development, the domestic grirem and Dalian Lu Ming respectively in aluminate powder, silicate green powder initially broke through the foreign patent restrictions, product quality and basic level abroad. As the LED red and green phosphors have good market prospects due to their wide range of excitation and emission, high luminous efficiency, good chemical and thermal stability. In the nitride / oxynitride patents, Japan MITSUBISHI chemical and other foreign enterprises occupy the advantage, and grirem and other units of the nitride / studied composition and preparation process of nitrogen oxide fluorescent powder, apply a series of patent.

Focus on quality rather than price

And energy-saving lamps with three primary fluorescent powder, LED phosphor has its uniqueness. One is the LED phosphor white LED devices accounted for only 1% of the cost to 2%, LED packaging manufacturers first concern is the quality of the products, rather than price, so the LED fluorescent powder on the market only first-class products to survive; two is a LED chip and package technology is in progress at the same time, the corresponding performance requirements of fluorescent powder continuous improvement and change. Only with a strong R & D accumulation and strong sustainable innovation ability of enterprises to survive; three is the Chinese LED most of the products are export rather than domestic patent, the requirements for fluorescent powder, fluorescent powder has no patent is difficult to enter the market. Based on the above reasons, although the current domestic claims can produce LED fluorescent powder manufacturers not under 20, in addition to grirem and a few enterprises products into the market, the market of white LED phosphors is fundamental for Japan (chemical market brand for Taiwan hongdae) and occupied by American intematix, made of white LED phosphors the market share of less than 20%. In recent years, Japan MITSUBISHI chemical with nitride advantage is also rapidly seize market share, and recently announced investment in Xi'an set up production plants in LED phosphor.

Grirem in phosphor research has been 40 years of history, is engaged in the development of LED phosphor has 10 years of history, has been in aluminate and silicate, aluminum silicate and nitride phosphor system and related devices for LED more than 30 Chinese invention patents and more than and 10 foreign patents, has more than 10 China the invention patent and 5 foreign countries such as the United States Patent authorized. Through the implementation of the patent license, to protect the interests of many domestic packaging manufacturers. According to our experience, to enhance the market share of domestic LED phosphors, not only to make efforts on the existing phosphor system, but also to further accelerate the development of new fluorescent powder, and access to independent intellectual property rights. Only in this way can we gain more right to speak in the market, so as to further protect the health and sustainable development of China's LED industry.