Method for manufacturing white-light LED fluorescent film based on 3D printing technology

Abstract

The invention discloses a method for manufacturing a white-light LED fluorescent film based on the 3D printing technology. The method for manufacturing the white-light LED fluorescent film based on the 3D printing technology comprises the following steps that (1) fluorescent powder slurry is prepared; (2) a 3D printer is introduced, and the fluorescent film is printed on an LED chip or on other transparent substrates under the control of a computer; (3) the printed film is cured simultaneously through hot wind scanning or ultraviolet light curing during printing; (4) integral curing is conducted according to an optimized heating technology or an optimized ultraviolet light curing method based on the property of colloid, and then the required fluorescent film is obtained. The method for manufacturing the white-light LED fluorescent film based on the 3D printing technology has the advantages that the printing precision is high, the automation degree is high, material waste is small, 3D patterns in various shapes and with various thicknesses can be printed on various substrates or various objects freely, the method is an advanced manufacturing technology, a complete 3D printer is available at present, automatic production can be achieved, and the method is quite suitable for manufacturing the white-light LED fluorescent film.

Description

technical field [0001] The invention belongs to the technical field of semiconductor lighting, and relates to a preparation method of a fluorescent film, in particular to a preparation method of a high-power white LED fluorescent film based on 3D printing technology. Background technique [0002] LED (Light Emitting Diode), that is, light-emitting diode, is a semiconductor all-solid-state light source. It is known as a new light source in the 21st century because of its advantages such as high efficiency, energy saving, environmental protection, long life, and rich colors. Among all semiconductor lighting sources, white LEDs are the most technically difficult. High brightness and high power are the current demand hotspots for white LEDs to enter the general lighting field, and they are also the key technical issues that current white LED products need to solve. At present, the mainstream technology of commercialized white light LED is made of blue light chip + yellow phospho...

AI Technical Summary

Problems solved by technology

At present, the mainstream technology of commercialized white light LED is made of blue light chip + yellow phosphor powder, and the dispensing process of yellow phosphor powder is the most common. Then, the fluorescent slurry is coated on the surface of the LED chip through the glue dispensing process, but the white LED fluorescent layer produced by the glue dispensing process has the following main problems: (1) Glue drops during the glue dispensing process After dropping onto the chip in a spherical shape, it is difficult to control the diffusion shape, thickness and surface micro-morphology of the glue spot. It is often easy to form a fluorescent layer with a thick middle and a thin surrounding. The uniformity of the glue spot is poor, which easily causes local yellowish or Bluish uneven light spots appear; (2) Due to the large proportion of the phosphor, it takes a certain period of time to fully cure after dispensing, so it is prone to phosphor sedimentation, which affects the uniformity of light output. It will reflect or scatter light, resulting in a decrease in light extraction efficiency; (3) It is difficult to accurately control the amount of phosphor powder, coupled with the operating status and differences of equipment in the actual operation process, the size and size of the phosphor film in the same batch of products The shape is also prone to differences, resulting in poor product consistency; (4) With the development of high-power white LED devices, the requirements for large-area uniform film formation are increasing, and the remote phosphor technology (that is, separating the phosphor from the chip) is increasingly The more attention is paid to it, and the traditional dispensing process is difficult to achieve a large area of ​​uniform film formation, so the application of this technology is limited

[0003] The patent application with the publication number CN101882663A discloses a preparation method of LED fluorescent layer by spraying. It first prepares the phosphor paste suitable for spraying, and then performs physical masking through the hole mask plate, and then uses the spraying technology to Spraying the fluorescent film on the opening area, this method improves the uniformity of the fluorescent film to a certain extent, but because the spraying process requires the use of a physical mask, and the high-precision physical mask technology is expensive, and the mask hole The edge of the edge is also prone to shadow effects, which will also cause unevenness of the film layer to a certain extent. In addition, the phosphor powder is easy to waste during the spraying process and its amount is difficult to control.

[0004] The patent application with the publication number CN10847680A discloses a method for producing white LED film by using screen printing technology. Using screen printing technology can greatly improve the uniformity of the fluorescent layer, but screen printing has higher requirements for paste , and it will also cause waste of phosphor powder, which is not conducive to the reduction of LED manufacturing costs

In addition, this method can only be printed on other transparent planar carriers, and it is difficult to directly make a fluorescent layer on the chip.

[0005] In addition, Lumileds and its publication number CN102842655A have applied for an invention patent, which discloses the technology of preparing fluorescent film layer by photolithography process, but the process is complicated and the cost is high, so that this technology has not been able to realize industrial application.