LED lamp panel, manufacturing method thereof and backlight module

Abstract

The invention relates to an LED lamp panel, a manufacturing method thereof and a backlight module, and the method comprises the steps: installing an LED chip on a substrate, and obtaining a lamp panel blank plate; forming a packaging adhesive layer on the surface of the lamp panel blank plate; after the packaging adhesive layer is cured, laser is adopted to cut a range corresponding to a preset position of the packaging adhesive layer, a reflection groove is formed in the packaging adhesive layer, a reflection material is arranged at the bottom of the reflection groove, and a reflection layer is formed at the bottom of the reflection groove, the range corresponding to the preset position of the packaging adhesive layer is located between the LED chips. After the packaging adhesive layer is solidified, laser is used for cutting the packaging adhesive layer to form the reflection grooves, the situations of deformation and uneven height caused by the fact that the packaging adhesive layer is pressed are effectively avoided, the thickness of the LED lamp panel is made to be uniform, the yield is effectively improved, and the light emitting effect is optimized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of LED lamp plate manufacturing, in particular to an LED lamp plate, a manufacturing method thereof and a backlight module. BACKGROUND

[0002] The backlight module is commonly used for backlight illumination of a liquid crystal display. The backlight module is usually composed of a backlight LED lamp plate, a lens, a diffusion plate and the like.

[0003] In order to make the LED lamp plate have a better reflection effect, a reflective layer needs to be coated on the conventional LED lamp plate, and the light of the LED lamp is reflected by the reflective layer to achieve a better backlight effect. However, in the manufacturing process of the conventional LED lamp plate, the reflective layer is first coated on the surface of the lamp plate, then solder paste is brushed on the pad position of the lamp plate, and the LED chip is placed on the pad. After reflow soldering, the LED chip is fixed on the pad. However, after reflow soldering, the reflection effect of the reflective layer is also affected.

[0004] In order to avoid the reflection effect of the reflective layer from being reduced after reflow soldering, the following scheme is adopted in the prior art CN111722432A: placing an LED chip on a lamp plate substrate; setting a transparent gel layer on the LED chip; setting a reflective layer on the surface of a pressing head; when the transparent gel layer is not cured, using the pressing head to press a groove part at the transparent gel layer, and the reflective layer is formed in the groove part. In this way, the reflective layer is avoided from being affected by reflow soldering, the light irradiation on the surface of the LED lamp plate is reduced, and the final light efficiency is improved.

[0005] However, the above method has problems. Since the transparent gel layer is not cured, the transparent gel layer is pressed by the pressing head, which easily causes the local part of the transparent gel layer to be raised, resulting in the surface of the transparent gel layer being uneven and the height being non-uniform, which affects the overall quality of the backlight module. SUMMARY

[0006] Therefore, it is necessary to provide an LED lamp plate, a manufacturing method thereof and a backlight module.

[0007] An LED lamp plate comprises: An LED chip is mounted on a substrate to obtain a lamp plate blank; An encapsulation gel layer is formed on the surface of the lamp plate blank; After the encapsulation gel layer is cured, a range corresponding to a preset position of the encapsulation gel layer is cut by using a laser to form a reflective groove on the encapsulation gel layer, a reflective material is arranged on the bottom of the reflective groove, and a reflective layer is formed on the bottom of the reflective groove. The range corresponding to the preset position of the encapsulation gel layer is located between each LED chip.

[0008] In one of the embodiments, the step of setting the reflective material at the bottom of the reflective groove to form the reflective layer at the bottom of the reflective groove comprises: In one of the embodiments, the step of setting the reflective material at the bottom of the reflective groove to form the reflective layer at the bottom of the reflective groove comprises:

[0009] In one of the embodiments, the step of setting the reflective material at the bottom of the reflective groove to form the reflective layer at the bottom of the reflective groove is followed by: The transparent layer is filled in the reflective groove, and the surface of the transparent layer is a flat surface.

[0010] In one of the embodiments, the step of forming the encapsulation layer on the surface of the lamp panel comprises: The encapsulation layer is formed on the surface of the lamp panel, and the thickness of the encapsulation layer is equal to the thickness of the LED chip. The step of setting the reflective material at the bottom of the reflective groove to form the reflective layer at the bottom of the reflective groove after the encapsulation layer is cured, comprises: The step of setting the reflective material at the bottom of the reflective groove to form the reflective layer at the bottom of the reflective groove after the encapsulation layer is cured, comprises: The reflective material liquid is sprayed on the surface of the encapsulation layer so that the reflective material liquid enters the reflective groove. The reflective material liquid on the surface of the encapsulation layer is scraped off before the reflective material liquid is cured by using a silica gel scraper plate, and the silica gel scraper plate is inclined to the surface of the encapsulation layer when moving on the surface of the encapsulation layer. A transparent layer is coated on the surface of the encapsulation layer.

[0011] In one of the embodiments, the encapsulation layer covers the outer side of the LED chip, and a reflective material microcapsule is arranged in the preset position of the encapsulation layer, and the preset position is located between the LED chips. The step of setting the reflective material at the bottom of the reflective groove to form the reflective layer at the bottom of the reflective groove after the encapsulation layer is cured, comprises: After the encapsulation layer is cured, a laser is used to cut a range corresponding to the preset position of the encapsulation layer, to form a reflective groove on the encapsulation layer, and to cut the surface layer of the reflective material microcapsule located in the reflective groove, so that the reflective material in the reflective material microcapsule is ejected to the bottom of the reflective groove, to form a reflective layer on the bottom of the reflective groove.

[0012] In one of the embodiments, the encapsulation layer comprises a first encapsulation sublayer and a second encapsulation sublayer. The step of forming the encapsulation layer on the surface of the lamp panel comprises: The first encapsulation sublayer is arranged around the outer side of the LED chip, and the thickness of the first encapsulation sublayer is smaller than the thickness of the LED chip. The reflective material microcapsule is arranged at the first preset position of the first encapsulation sublayer, and the first preset position is located between the LED chips. The second encapsulation sublayer is formed on the surface of the first encapsulation sublayer and the reflective material microcapsule, and the second encapsulation sublayer is arranged on the outer side of the LED chip and the reflective material microcapsule. The step of forming the reflective layer on the bottom of the reflective groove after the encapsulation layer is cured, the laser is used to cut a range corresponding to the preset position of the encapsulation layer, to form a reflective groove on the encapsulation layer, and to cut the surface layer of the reflective material microcapsule located in the reflective groove, so that the reflective material in the reflective material microcapsule is ejected to the bottom of the reflective groove, to form a reflective layer on the bottom of the reflective groove comprises: After the second encapsulation sublayer is cured, a laser is used to cut a range corresponding to the second preset position of the second encapsulation sublayer, to form a reflective groove on the second encapsulation sublayer, and to cut the surface layer of the reflective material microcapsule located in the reflective groove, so that the reflective material in the reflective material microcapsule is ejected to the reflective groove, to form a reflective layer.

[0013] In one of the embodiments, the material of the first encapsulation sublayer is the same as the material of the second encapsulation sublayer.

[0014] In one of the embodiments, the projection of the first preset position on the lamp panel is located in the projection range of the second preset position of the second encapsulation sublayer on the lamp panel.

[0015] A backlight module comprises the LED lamp panel manufactured by the manufacturing method of the LED lamp panel in any of the above embodiments.

[0016] The aforementioned LED light board and its manufacturing method, as well as the backlight module, use a laser to cut the encapsulating adhesive layer after it has cured to form reflective grooves. This effectively avoids deformation and uneven height caused by pressure on the encapsulating adhesive layer, resulting in uniform thickness of the LED light board, effectively improving the yield rate, and optimizing the light output effect. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic flowchart illustrating a method for manufacturing an LED light board according to one embodiment; Figures 2A to 2F This is a schematic diagram of the manufacturing process of an LED light board according to one embodiment.

[0019] Explanation of reference numerals in the attached figures: 200, Substrate; 210, LED chip; 300, Encapsulating adhesive layer; 310, First encapsulating adhesive layer; 320, Second encapsulating adhesive layer; 400, Reflective material microcapsule; 301, Reflective groove; 510, Transparent layer. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] It is worth mentioning that the LED light board in each embodiment is a mini LED light board, and the LED chip is a mini LED chip. Mini LEDs are characterized by their small size and ability to be densely arranged, making them suitable for backlighting screens of electronic devices of various sizes.

[0022] like Figure 1 As shown, this is a method for manufacturing an LED light board according to an embodiment of the present invention, comprising: Step 110: Install the LED chip on the substrate to obtain the lamp board prototype.

[0023] In the embodiment, a lamp panel prototype is obtained. Specifically, first, solder paste is applied to the pad positions of the substrate, then the pins of the LED chips are aligned with the pads, the LED chips are placed on the pads, then the substrate is placed in a reflow soldering furnace, the LED chips and the substrate are reflow soldered, the LED chips are fixedly installed on the substrate, thereby obtaining the lamp panel prototype.

[0024] In step 120, an encapsulation glue layer is formed on the surface of the lamp panel prototype.

[0025] In the embodiment, the encapsulation glue layer is also referred to as a transparent glue layer, and is made of transparent material, for example, the encapsulation glue layer is transparent epoxy resin. The encapsulation glue layer covers the LED chips, and when the LED chips emit light, the emitted light is transmitted through the encapsulation glue layer to the outside. In the embodiment, encapsulation glue is applied or sprayed on the surface of the lamp panel prototype, and the encapsulation glue covers the LED chips to form an encapsulation glue layer covering the LED chips on the surface of the lamp panel prototype.

[0026] In step 130, after the encapsulation glue layer is cured, a laser is used to cut the range corresponding to the preset positions of the encapsulation glue layer, a reflection groove is formed on the encapsulation glue layer, a reflection material is arranged at the bottom of the reflection groove, and a reflection layer is formed at the bottom of the reflection groove, wherein the ranges corresponding to the preset positions of the encapsulation glue layer are respectively located between the LED chips.

[0027] In the embodiment, after the encapsulation glue layer is cured, it is not easy to deform, and the thickness (height) of the formed encapsulation glue layer is uniform, which can make the thickness of the encapsulation glue layer covering the surface layer of the LED chips uniform and the surface flat. Then, a laser cutting technology is used to cut the range corresponding to the preset positions of the encapsulation glue layer. It is worth mentioning that the encapsulation glue layer has multiple preset positions, and the range corresponding to each preset position is located between adjacent LED chips, so that the formed reflection groove is located between the LED chips, and then a reflection material is sprayed or applied at the bottom of the reflection groove, and the reflection material forms a reflection layer at the bottom of the reflection groove. In one embodiment, the reflection material includes white oil.

[0028] It is worth mentioning that, compared with the traditional LED lamp panel in which white oil is applied on the substrate, in the embodiment, the reflection layer is arranged in the reflection groove, which can effectively avoid the reflection layer on the substrate affecting the reflection effect after reflow soldering.

[0029] In addition, in some other schemes, reflow soldering is first performed, and then the reflective layer (white oil) is coated. In this method, due to the need for the reflective layer to accurately avoid the LED chip, a high-precision mask is required, which is costly. In addition, if high-temperature curing is required after the reflective layer is coated, the solder joints of the already soldered LED chip will crack, which is not conducive to maintaining the stability of the lamp panel. In addition, after reflow soldering, the surface of the substrate may be left with flux or an oxide layer, which will reduce the adhesion of the reflective layer. Therefore, in the present embodiment, the reflective layer is arranged in the reflective groove, which can effectively isolate the LED chip and avoid affecting the LED chip, and also avoids the cracking of the solder joints of the LED chip, which leads to poor contact of the LED chip. In addition, the adhesion of the reflective layer is higher, which effectively prevents the reflective layer from falling off.

[0030] In the above embodiment, after the encapsulation adhesive layer is cured, the encapsulation adhesive layer is cut by laser to form the reflective groove, which effectively avoids the deformation and height unevenness of the encapsulation adhesive layer caused by pressure, so that the thickness of the LED lamp panel is uniform, which effectively improves the yield and optimizes the light output effect.

[0031] In one embodiment, the step of arranging the reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove comprises: In one embodiment, the step of arranging the reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove comprises:

[0032] In the present embodiment, the flow control inkjet printing technology is a combination of microfluidic technology and inkjet printing technology, which realizes high-precision generation and positioning of liquid droplets through micron-level channels and nozzles, so as to avoid spraying to positions outside the reflective groove and accurately spray the reflective material at the bottom of the reflective groove. In one embodiment, the flow control inkjet printing technology is used to spray the reflective material at the bottom of the reflective groove to form a reflective layer by using a mask. The use of a mask to spray the reflective material can accurately align the reflective material with each reflective groove and avoid blocking the light emitted by the LED chip.

[0033] In one embodiment, the distance from the top surface of the reflective layer to the substrate is less than the distance from the top surface of the LED chip to the substrate. In the present embodiment, the sum of the height of the bottom of the reflective groove to the substrate and the thickness of the reflective layer is less than the thickness of the LED chip, so that the top surface of the reflective layer is located below the light emitting direction of the LED chip, which is conducive to the full reflection of the light emitted by the LED chip by the reflective layer.

[0034] In one embodiment, the step of arranging the reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove further comprises: A transparent layer is coated on the surface of the encapsulation adhesive layer, the transparent layer fills the reflection groove, and the surface of the transparent layer is a flat surface.

[0035] In the embodiment, the material of the transparent layer can be the same as that of the encapsulation adhesive layer. The encapsulation adhesive layer is used for encapsulating and covering the LED chip and for light transmission. The transparent layer is used for filling the emission groove, covering the surface of the reflection layer, and covering the surface of the encapsulation adhesive layer, so that the surface of the LED lamp panel is flat, and the light emission of the LED lamp panel is more uniform. In one embodiment, the material of the transparent layer is transparent epoxy resin.

[0036] In one embodiment, the step of forming the encapsulation adhesive layer on the surface of the lamp panel wafer includes: forming the encapsulation adhesive layer on the surface of the lamp panel wafer, wherein the thickness of the encapsulation adhesive layer is equal to the thickness of the LED chip. After the encapsulation adhesive layer is cured, a range corresponding to a preset position of the encapsulation adhesive layer is cut by using a laser to form a reflection groove on the encapsulation adhesive layer, a reflection material is arranged at the bottom of the reflection groove, and a reflection layer is formed at the bottom of the reflection groove. After the encapsulation adhesive layer is cured, a range corresponding to a preset position of the encapsulation adhesive layer is cut by using a laser to form a reflection groove on the encapsulation adhesive layer. The reflection material liquid is sprayed on the surface of the encapsulation adhesive layer to make the reflection material liquid enter the reflection groove. Before the reflection material liquid is cured, a silica gel scraper is used to scrape off the reflection material liquid on the surface of the encapsulation adhesive layer, wherein the silica gel scraper is inclined to the surface of the encapsulation adhesive layer when moving on the surface of the encapsulation adhesive layer. A transparent adhesive layer is coated on the surface of the encapsulation adhesive layer.

[0037] In the embodiment, the thickness of the encapsulation layer on the substrate is the same as the height of the LED chip on the substrate after the encapsulation layer is cured and formed. In this way, the surface of the encapsulation layer is flush with the top surface of the LED chip. After the encapsulation layer is cured, the encapsulation layer is cut by using a laser to form a plurality of reflection grooves. Subsequently, a reflective material liquid, such as white oil, is sprayed on the surface of the encapsulation layer. A silicone scraper is used to scrape off the reflective material liquid on the surface of the encapsulation layer. The silicone scraper has good elasticity and anti-static properties, can adapt to the slight unevenness of the surface of the encapsulation layer, avoid scratches on the surface of the encapsulation layer caused by hard contact, and can fully adhere to the surface of the encapsulation layer to fully scrape off the reflective material liquid on the surface of the encapsulation layer. The angle between the silicone scraper and the surface of the encapsulation layer along the advancing direction of the silicone scraper is 15° to 30°. It is worth mentioning that if the angle between the silicone scraper and the surface of the encapsulation layer is too large, the friction will be large, which will cause the silicone scraper to vibrate, form edge accumulation, and easily cause the encapsulation layer to deform. If the angle between the silicone scraper and the surface of the encapsulation layer is too small, the shear force will be insufficient, resulting in a large amount of residual reflective material liquid. Therefore, in the embodiment, the silicone scraper is inclined along the advancing direction of the silicone scraper, so that the angle between the silicone scraper and the surface of the encapsulation layer is 15° to 30°, which can effectively protect the encapsulation layer and fully scrape off the reflective material liquid.

[0038] In the embodiment, the surface of the encapsulation layer is flush with the top surface of the LED chip, so that the surface of the encapsulation layer remains flat, which is beneficial to the scraping of the reflective material liquid. After the reflective material liquid on the surface of the encapsulation layer is scraped off, the reflective material liquid in the reflection grooves is retained, so that the reflective material liquid is cured in the reflection grooves to form a reflection layer. Subsequently, a transparent layer is applied on the surface of the encapsulation layer. The material of the transparent layer can be the same as that of the encapsulation layer. The transparent layer is used to fill the emission grooves, cover the surface of the reflection layer, and cover the surface of the encapsulation layer, so that the surface of the LED lamp panel is flat and the light emitted by the LED lamp panel is more uniform. In one embodiment, the material of the transparent layer is transparent epoxy resin.

[0039] In order to make the height of the reflective material liquid drop, so that the height of the formed reflective layer is lower than the surface of the encapsulation layer and the height of the LED chip, in an embodiment, the surface of the silicone scraping plate is provided with a plurality of convex points, the diameter of the convex points is 50-80 μm, and the thickness is 30-90 μm, and the bottom of the reflective groove is provided with a reflective accommodating groove, so that the bottom of the reflective groove forms a stepped structure. In this way, the reflective material liquid will fill the reflective groove and the reflective accommodating groove, when the silicone scraping plate is scraped, the convex points will penetrate into the reflective groove, and the part of the reflective material liquid in the reflective groove will be scraped off, so that the height of the reflective material liquid drops, and because the bottom of the reflective groove is provided with the reflective accommodating groove, the residual reflective material liquid can be retained in the reflective accommodating groove, so that the reflective material liquid in the reflective accommodating groove is avoided to be scraped off, so that the height of the reflective material liquid can drop, and the reflective material liquid on the surface of the encapsulation layer can be fully scraped off. In order to make the height of the reflective material liquid in the reflective groove drop, and make the reflective material liquid on the surface of the encapsulation layer be fully scraped off, the silicone scraping plate can be used repeatedly for scraping.

[0040] In the embodiment, because the height of the liquid surface of the reflective material liquid drops and is lower than the surface of the encapsulation layer, the height of the formed reflective layer is lower than the height of the LED chip, so that a good reflective effect can be obtained.

[0041] In an embodiment, in the step of forming the encapsulation layer on the surface of the lamp panel, the encapsulation layer covers the outer side of the LED chip, and the reflective material microcapsules are arranged in the preset position of the encapsulation layer, and the preset position is located between the LED chips. The step of forming the reflective groove on the encapsulation layer after the encapsulation layer is cured, and cutting the range corresponding to the preset position of the encapsulation layer by using laser, and arranging the reflective material on the bottom of the reflective groove, and forming the reflective layer on the bottom of the reflective groove includes: The step of forming the reflective groove on the encapsulation layer after the encapsulation layer is cured, and cutting the range corresponding to the preset position of the encapsulation layer by using laser, and arranging the reflective material on the bottom of the reflective groove, and forming the reflective layer on the bottom of the reflective groove includes:

[0042] In the embodiment, the preset position of the encapsulation adhesive layer is pre-wrapped with a reflective material microcapsule, and the reflective material microcapsule is wrapped with a reflective material. When the encapsulation adhesive layer is cut by using the laser, the edge of the range corresponding to the preset position is cut first, and then the inside is gradually cut, so as to form a reflective groove. Then, the surface of the reflective material microcapsule is cut by using the laser, so that the reflective material in the reflective material microcapsule is sprayed to the bottom of the reflective groove, thereby forming a reflective layer at the bottom of the reflective groove. It is worth mentioning that, since the reflective material microcapsule is pre-set in the encapsulation adhesive layer, the reflective material microcapsule can be directly cut by using the laser cutting, without the need for an additional coating process of the reflective material, thereby effectively improving the efficiency and reducing the cost.

[0043] It is worth mentioning that the reflective material microcapsule is filled with a reflective material, for example, the reflective material includes white oil, and for example, the reflective material contains a nano-TiO2 (titanium dioxide) suspension. In the embodiment, the size of the LED chip is 100-200 μm, the thickness of the LED chip is 80-150 μm, the distance between the LED chips is 100-150 μm, the diameter of the reflective material microcapsule is 30-50 μm, and the diameter of the reflective groove is 50-90 μm, so that the thickness of the reflective layer is 3-35 μm. It is worth mentioning that the reflective groove diameter needs to reserve a process tolerance of about 5-10 μm, which is caused by the error of laser cutting or material thermal deformation. For example, if the diameter of the reflective material microcapsule is 50 μm, and the diameter of the reflective groove is set to 60 μm, the positioning deviation of ±5 μm can be compatible, and the thickness of the reflective layer is 23 μm.

[0044] In one embodiment, as shown in Figure 2D the encapsulation adhesive layer includes a first encapsulation adhesive sub-layer and a second encapsulation adhesive sub-layer; please refer to Figures 2B to 2E the step of forming the encapsulation adhesive layer on the surface of the lamp panel blank includes: forming a first encapsulation adhesive sub-layer on the surface of the lamp panel blank, wherein the first encapsulation adhesive sub-layer is arranged around the outer side of the LED chip, and the thickness of the first encapsulation sub-layer is less than the thickness of the LED chip; setting a reflective material microcapsule at a first preset position of the first encapsulation adhesive sub-layer, wherein the first preset position is located between each LED chip; forming a second encapsulation adhesive sub-layer on the surface of the first encapsulation adhesive sub-layer and the reflective material microcapsule, and the second encapsulation adhesive sub-layer is wrapped around the outer side of each LED chip and each reflective material microcapsule; The step of forming the reflecting layer after the curing of the encapsulating adhesive layer, cutting the encapsulating adhesive layer at a preset position of the encapsulating adhesive layer by using a laser, and forming a reflecting groove on the encapsulating adhesive layer includes: After the curing of the second encapsulating adhesive sub-layer, a second preset position of the second encapsulating adhesive sub-layer is cut by using a laser, a reflecting groove is formed on the second encapsulating adhesive sub-layer, and the surface layer of the reflecting material microcapsule located in the reflecting groove is cut open, so that the reflecting material in the reflecting material microcapsule is sprayed into the reflecting groove to form a reflecting layer.

[0045] It is worth mentioning that the cutting depth of the encapsulating adhesive layer is greater than or equal to the thickness of the second encapsulating adhesive sub-layer, so that the reflecting material capsules can be exposed, facilitating laser cutting, and in addition, the height of the bottom of the reflecting groove is less than the height of the top surface of the LED chip, so that the reflecting effect of the reflecting layer located at the bottom of the reflecting groove is better. In addition, when the encapsulating adhesive layer is cut by laser, the encapsulating adhesive layer is gasified during the cutting process, and the reflecting material can effectively avoid gasification because it contains metal particles, such as nanoscale titanium dioxide. Therefore, the temperature of the laser is controlled to gasify the encapsulating adhesive layer and not to reach the gasification temperature of the metal particles, which can effectively realize the cutting of the encapsulating adhesive layer and avoid the gasification of the reflecting material.

[0046] In this embodiment, first, a transparent adhesive is coated or sprayed on the surface of the substrate to form a first encapsulating adhesive sub-layer, and the thickness of the first encapsulating adhesive sub-layer is less than the thickness of the LED chip, so that the reflecting material microcapsules on the first encapsulating adhesive sub-layer can be located below the LED chip, the first encapsulating sub-layer covers the surface of the substrate and surrounds the outside of the side surface of the LED chip. It is worth mentioning that the first encapsulating sub-layer can cover the top surface of the LED chip or not, and when the transparent adhesive is coated or sprayed, the LED chip does not need to be avoided, so that the forming efficiency of the first encapsulating adhesive sub-layer can be effectively improved. Subsequently, the reflecting material microcapsules are placed on the first encapsulating adhesive sub-layer, so that the reflecting material microcapsules are located between adjacent LED chips, and then the transparent adhesive is coated or sprayed on the surface of the first encapsulating adhesive sub-layer and covers the surface of the reflecting material microcapsules to form a second encapsulating adhesive sub-layer covering the outside of the reflecting material microcapsules, and the second encapsulating adhesive sub-layer also covers the top surface of the LED chip. After curing, the top surface of the second encapsulating adhesive sub-layer is a flat surface. In this way, the overall flatness of the encapsulating adhesive layer can be higher.

[0047] In the embodiment, the thickness of the first encapsulation glue sub-layer is 60-100 μm, so that the thickness of the first encapsulation glue sub-layer is less than the thickness of the LED chip, the thickness of the second encapsulation glue sub-layer is 90-200 μm, and the depth of the reflection groove formed downward along the surface of the second encapsulation glue sub-layer is 90-220 μm, so that, due to the depth of the reflection groove being much greater than the diameter of the reflection material microcapsule, the range of the reflection material liquid can be limited, and the reflection material liquid is prevented from diffusing to the area outside the reflection groove.

[0048] In the embodiment, the reflection material microcapsule is placed on the first encapsulation glue sub-layer, and then the second encapsulation glue sub-layer is coated or sprayed, so that the reflection material microcapsule is pre-buried in the second encapsulation glue sub-layer. After the reflection groove is formed by cutting the encapsulation glue layer, the reflection material microcapsule is cut, and the reflection material sprayed from the reflection material microcapsule is limited in range through the reflection groove formed by cutting, so that the reflection material is prevented from diffusing to the area outside the reflection groove, and the light emission of the LED chip is prevented from being blocked.

[0049] It is worth mentioning that, due to the position of the reflection material microcapsule being located in the first preset position within the range corresponding to the second preset position, the efficiency is higher compared with the scheme of first cutting to form the reflection groove, and then spraying or coating the reflection layer on the bottom of the reflection groove. On the one hand, due to the first preset position being located in the range corresponding to the second preset position, the accuracy of the first preset position does not need to be high, and only needs to be within the range corresponding to the second preset position. Moreover, the diffusion of the reflection material can be limited through the reflection groove formed by cutting, so that the reflection layer is formed in the reflection groove, and in the scheme of spraying the reflection layer in the reflection groove, the reflection groove needs to be accurately positioned, so that the spray head is accurately aligned with the reflection groove. In the case of the same step process, the accuracy requirement is lower, so that the efficiency is effectively improved, and the cost is effectively reduced. On the other hand, in order to accurately spray, the reflection material needs to be sprayed in the reflection groove using a mask, and in the embodiment, the reflection material microcapsule does not need to be placed with the mask. Therefore, compared with spraying the reflection material in the reflection groove, the difficulty of placing the reflection material microcapsule on the surface of the first encapsulation glue sub-layer is lower, and the irregular deformation and local protrusion of the encapsulation glue layer due to stress extrusion are effectively avoided, so that the flatness and stability of the encapsulation glue layer are effectively maintained.

[0050] In order to place the reflective material microcapsules on the surface of the first encapsulation glue sublayer, in an embodiment, the reflective material microcapsules are dispersed in liquid epoxy resin, the reflective material microcapsules wrapped in the liquid epoxy resin are positioned at the first preset position by inkjet printing, and after the liquid epoxy resin is cured, the reflective material microcapsules are fixed on the surface of the first encapsulation sublayer. Since the epoxy resin on the surface of the reflective material microcapsules is the same material as the first encapsulation glue sublayer and the second encapsulation glue sublayer, on the one hand, the reflective material microcapsules can be fixed on the surface of the first encapsulation sublayer by curing of the epoxy resin, and on the other hand, after the second encapsulation glue sublayer is coated, the epoxy resin on the surface of the reflective material microcapsules and the second encapsulation glue sublayer can be integrated, which is convenient for subsequent processing.

[0051] In order to enable the reflective material microcapsules to be more accurately sprayed to the bottom of the reflection groove after cutting, in an embodiment, the bottom of each reflection groove gradually inclines toward the substrate from the middle to the outer edge, that is, the depth of the reflection groove gradually increases from the middle to the outer edge, so that the bottom of the reflection groove inclines outward and downward, which facilitates diffusion and coverage of the reflective material liquid on the bottom of the reflection groove.

[0052] In an embodiment, the material of the first encapsulation glue sublayer is the same as that of the second encapsulation glue sublayer.

[0053] In the embodiment, the material of the first encapsulation glue sublayer and the material of the second encapsulation glue sublayer are both epoxy resin. The use of the same material makes the adhesion between the first encapsulation glue sublayer and the second encapsulation glue sublayer higher, enables the overall strength of the encapsulation glue layer to be higher, and enables the overall light transmission effect to be better.

[0054] In an embodiment, the projection of the first preset position on the lamp panel prototype is located in the projection range of the second preset position of the second encapsulation glue sublayer on the lamp panel prototype.

[0055] In the embodiment, the first preset position on the first encapsulation glue sublayer is the position where the reflective material microcapsules are placed, and the range corresponding to the second preset position of the second encapsulation glue sublayer is the range of the reflection groove. Therefore, the first preset position is located in the range corresponding to the second preset position in the direction perpendicular to the substrate, which enables the reflection groove to be cut around the position where the reflective material microcapsules are located during laser cutting, and enables the reflective material microcapsules to be located in the reflection groove.

[0056] In an embodiment, the reflective material microcapsule comprises a surface layer, a reflective material liquid, and a gasified pressurized liquid, and the surface layer is wrapped on the outer side of the reflective material liquid and the gasified pressurized liquid.

[0057] In this embodiment, the surface layer of the reflective material microcapsule is a polyurethane film, and the reflective material liquid is white oil. In one embodiment, the reflective material liquid is a nano-sized titanium dioxide (TiO2) suspension, and the vaporization pressurization liquid is liquid CO2. Specifically, the polyurethane film is used to encapsulate the reflective material liquid and the vaporization pressurization liquid. When the surface layer of the reflective material microcapsule is laser-cut, the vaporization pressurization liquid instantly heats up and vaporizes, increasing the internal pressure of the reflective material microcapsule. In addition, the polyurethane film also produces CO2 through thermal decomposition under laser irradiation. Thus, the large gas pressure can instantly break through the surface layer of the polyurethane film, causing the reflective material liquid located on the surface layer to be released under instantaneous pressure and sprayed into the reflective groove, coating the bottom of the reflective groove, thereby forming a reflective layer. Since both the polyurethane film and CO2 vaporize during the heating process, materials other than the reflective material liquid remain in the reflective groove.

[0058] To fabricate reflective material microcapsules, in one embodiment, the method further includes: fabricating reflective material microcapsules using a microfluidic dual emulsion method. Specifically, a coaxial microfluidic device is used to fabricate reflective material microcapsules. Liquid reflective material and CO2 are injected into the inner channel of the coaxial microfluidic device, and a mixture of polyurethane (PU) and polymethyl methacrylate (PMMA) is injected into the outer channel. The flow rate of the liquid reflective material in the inner channel is 0.1-0.5 mL / min, and the flow rate of the mixture in the outer channel is 0.2-0.8 mL / min. When the liquid substances flow out of the inner and outer channels, an ultraviolet light source set at the microfluidic outlet is used to irradiate the liquid substances, triggering the polyurethane to undergo photocrosslinking to form a surface layer, encapsulating the reflective material liquid and CO2 inside, thereby forming reflective material microcapsules.

[0059] It is worth mentioning that when the microcapsules of the reflective material rupture, most of the reflective material liquid is sprayed onto the bottom of the reflective groove, with only a small portion located on the sidewall of the reflective groove. The solidified reflective layer of the reflective material liquid on the sidewall of the reflective groove will not affect the light output of the LED chip. In addition, the reflective layer adhering to the sidewall of the reflective groove can be reduced by cutting the sidewall of the reflective groove outward through secondary laser cutting.

[0060] In one embodiment, an LED light board and a method for manufacturing the same are provided, comprising: Step 1, as follows Figure 2A As shown, LED chip 210 is mounted on substrate 200 to obtain a prototype lamp board.

[0061] Step two, as Figure 2B As shown, a first encapsulation layer 310 is formed on the surface of the LED chip 210, wherein the first encapsulation layer 310 is disposed around the outside of the LED chip 210, and the thickness of the first encapsulation layer is less than the thickness of the LED chip 210.

[0062] Step 3, as Figure 2C As shown, a reflective material microcapsule 400 is disposed at a first preset position in the first encapsulation gluon layer 310, wherein the first preset position is located between each of the LED chips 210.

[0063] Step four, as Figure 2D As shown, a second encapsulation layer 320 is formed on the surface of the first encapsulation layer 310 and the reflective material microcapsule 400, and the second encapsulation layer 320 covers the outer side of each LED chip 210 and each reflective material microcapsule 400.

[0064] Step 5, as Figure 2E As shown, after the second encapsulation layer 320 is cured, a laser is used to cut the area corresponding to the second preset position of the second encapsulation layer 320 to form a reflective groove 301 on the second encapsulation layer 320. The surface of the reflective material microcapsule 400 located in the reflective groove 301 is cut open so that the reflective material in the reflective material microcapsule 400 is sprayed into the reflective groove 301 to form a reflective layer.

[0065] Step six, as Figure 2F As shown, a transparent layer 510 is coated on the surface of the encapsulating adhesive layer 300. The transparent layer 510 fills the reflective groove 301, and the surface of the transparent layer 510 is flat.

[0066] In one embodiment, an LED light board is provided, which is manufactured using the LED light board manufacturing method described in any of the above embodiments.

[0067] In one embodiment, a backlight module is provided, including the LED light panel described in any of the above embodiments.

[0068] The aforementioned LED light board and its manufacturing method, as well as the backlight module, use a laser to cut the encapsulating adhesive layer after it has cured to form reflective grooves. This effectively avoids deformation and uneven height caused by pressure on the encapsulating adhesive layer, resulting in uniform thickness of the LED light board, effectively improving the yield rate, and optimizing the light output effect.

[0069] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A method of manufacturing an LED light panel, characterized by, The application relates to a method for manufacturing a lamp panel. The LED chip is installed on a substrate to obtain a lamp panel; A packaging glue layer is formed on the surface of the lamp panel; After the packaging glue layer is cured, a preset position of the packaging glue layer is cut by laser to form a reflection groove on the packaging glue layer, a reflection material is arranged at the bottom of the reflection groove, and a reflection layer is formed at the bottom of the reflection groove, wherein the preset position of the packaging glue layer corresponds to a range between each LED chip.

2. The method of manufacturing an LED lamp panel according to claim 1, wherein, The step of arranging the reflection material at the bottom of the reflection groove and forming the reflection layer at the bottom of the reflection groove comprises the following steps: The reflection material is sprayed on the bottom of the reflection groove by using a flow control inkjet printing technology to form the reflection layer at the bottom of the reflection groove.

3. The method of claim 1, wherein After the step of arranging the reflection material at the bottom of the reflection groove and forming the reflection layer at the bottom of the reflection groove, the following step is further included: A transparent layer is coated on the surface of the packaging glue layer, the transparent layer is filled in the reflection groove, and the surface of the transparent layer is a flat surface.

4. The method of claim 1, wherein The step of forming the packaging glue layer on the surface of the lamp panel comprises the following steps: The packaging glue layer is formed on the surface of the lamp panel, wherein the thickness of the packaging glue layer is equal to the thickness of the LED chip; The step of arranging the reflection material at the bottom of the reflection groove and forming the reflection layer at the bottom of the reflection groove comprises the following steps: After the packaging glue layer is cured, a preset position of the packaging glue layer is cut by laser to form a reflection groove on the packaging glue layer; The reflection material liquid is sprayed on the surface of the packaging glue layer to make the reflection material liquid enter the reflection groove; Before the reflection material liquid is cured, the reflection material liquid on the surface of the packaging glue layer is scraped off by using a silica gel scraper, wherein the silica gel scraper is inclined to the surface of the packaging glue layer when moving on the surface of the packaging glue layer; A transparent glue layer is coated on the surface of the packaging glue layer.

5. The method of claim 1, wherein In the step of forming the packaging glue layer on the surface of the lamp panel, the packaging glue layer covers the outer side of the LED chip, and a reflection material microcapsule is arranged in a preset position of the packaging glue layer, wherein the preset position is between each LED chip; The step of arranging the reflection material at the bottom of the reflection groove and forming the reflection layer at the bottom of the reflection groove comprises the following steps: After the packaging glue layer is cured, a preset position of the packaging glue layer is cut by laser to form a reflection groove on the packaging glue layer, and the surface layer of the reflection material microcapsule in the reflection groove is cut to make the reflection material in the reflection material microcapsule spray to the bottom of the reflection groove to form the reflection layer at the bottom of the reflection groove.

6. The method of manufacturing an LED lamp panel according to claim 5, wherein The packaging glue layer comprises a first packaging glue sublayer and a second packaging glue sublayer; The step of forming the encapsulation glue layer on the surface of the lamp panel wafer comprises: forming a first encapsulation glue sub-layer on the surface of the lamp panel wafer, wherein the first encapsulation glue sub-layer is arranged around the outer side of the LED chip, and the thickness of the first encapsulation sub-layer is less than the thickness of the LED chip; arranging reflective material microcapsules at first preset positions of the first encapsulation glue sub-layer, wherein the first preset positions are located between the LED chips; forming a second encapsulation glue sub-layer on the surface of the first encapsulation glue sub-layer and the reflective material microcapsules, and the second encapsulation glue sub-layer is arranged on the outer side of each LED chip and each reflective material microcapsule; after the encapsulation glue layer is solidified, cutting the range corresponding to the preset position of the encapsulation glue layer by using a laser, forming a reflective groove on the encapsulation glue layer, arranging reflective material on the bottom of the reflective groove, and forming a reflective layer on the bottom of the reflective groove, wherein the step comprises: after the second encapsulation glue sub-layer is solidified, cutting the range corresponding to the second preset position of the second encapsulation glue sub-layer by using a laser, forming a reflective groove on the second encapsulation glue sub-layer, and cutting the surface layer of the reflective material microcapsule located in the reflective groove, so that the reflective material in the reflective material microcapsule is sprayed into the reflective groove to form a reflective layer.

7. The method of manufacturing an LED lamp panel according to claim 6, wherein The material of the first encapsulation glue sub-layer is the same as that of the second encapsulation glue sub-layer.

8. The method of claim 6, wherein, The projection of the first preset position on the lamp panel wafer is located in the projection range of the range corresponding to the second preset position of the second encapsulation glue sub-layer on the lamp panel wafer.

9. An LED light panel, characterized by The LED lamp panel is manufactured by using the manufacturing method of any one of claims 1-8.

10. A backlight module, characterized in that, The LED lamp panel comprises the LED lamp panel of claim 9. The LED lamp panel comprises the LED lamp panel of claim 9.

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