LED lamp panel and manufacturing method thereof, backlight module

Abstract

The present application relates to LED lamp plate and its manufacturing method, backlight module, the method includes installing LED chip on the substrate, obtains the lamp plate embryo board;Form the encapsulation glue layer on the surface of the lamp plate embryo board;After the encapsulation glue layer solidifies, the range corresponding to the preset position of the encapsulation glue layer is cut using laser, forms the reflection groove on the encapsulation glue layer, sets up the reflection material at the bottom of the reflection groove, forms the reflection layer at the bottom of the reflection groove, wherein the range corresponding to the preset position of the encapsulation glue layer is located between each LED chip respectively.In the encapsulation glue layer solidifies, then the encapsulation glue layer is cut using laser to form the reflection groove, effectively avoids the deformation and height inhomogeneous condition caused by the encapsulation glue layer under pressure, makes the thickness of LED lamp plate uniform, effectively improves the yield, and optimizes the light extraction effect.

Description

Technical Field

[0001] This invention relates to the field of LED light board manufacturing technology, and in particular to an LED light board and its manufacturing method, and a backlight module. Background Technology

[0002] Backlight modules are commonly used for backlighting in LCD displays. A backlight module typically consists of a backlight LED panel, a lens, a diffuser plate, etc.

[0003] To achieve better reflection in LED light panels, traditional LED light panels require a reflective layer to reflect the light from the LEDs, thus achieving a better backlight effect. However, in the traditional LED light panel manufacturing process, a reflective layer is first coated onto the surface of the light panel, then solder is applied to the pads, and LED chips are placed on the pads. After reflow soldering, the LED chips are fixed to the pads, but the reflective effect of the reflective layer is also affected after reflow soldering.

[0004] To avoid a decrease in reflectivity due to reflow soldering of the reflective layer, the prior art CN111722432A employs the following solution: An LED chip is placed on the LED substrate; a transparent colloid layer is deposited on the LED chip; a reflective layer is deposited on the surface of the pressing head; and before the transparent colloid layer cures, a groove is pressed into the transparent colloid layer using the pressing head, forming the reflective layer within the groove. This avoids the reflective layer being affected by reflow soldering, reduces light irradiation on the LED substrate surface, and improves the final light extraction efficiency.

[0005] However, the above approach has problems. Since the transparent adhesive layer is not cured, pressing the transparent adhesive layer with the pressing head can easily cause local bulges in the transparent adhesive layer, resulting in an uneven surface and uneven height of the transparent adhesive layer, which affects the overall quality of the backlight module. Summary of the Invention

[0006] Therefore, it is necessary to provide an LED light board and its manufacturing method, as well as a backlight module.

[0007] An LED light panel, comprising:

[0008] The LED chips are mounted on the substrate to obtain the lamp board prototype.

[0009] An encapsulating adhesive layer is formed on the surface of the lamp board prototype;

[0010] After the encapsulating adhesive layer is cured, a laser is used to cut the area corresponding to the preset position of the encapsulating adhesive layer to form a reflective groove on the encapsulating adhesive layer. A reflective material is placed at the bottom of the reflective groove, and a reflective layer is formed at the bottom of the reflective groove. The area corresponding to the preset position of the encapsulating adhesive layer is located between each of the LED chips.

[0011] In one embodiment, the step of distributing a reflective material at the bottom of the reflective groove and forming a reflective layer at the bottom of the reflective groove includes:

[0012] Using flow control inkjet printing technology, reflective material is sprayed onto the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove.

[0013] In one embodiment, after the step of distributing reflective material at the bottom of the reflective groove and forming a reflective layer at the bottom of the reflective groove, the method further includes:

[0014] A transparent layer is coated on the surface of the encapsulating adhesive layer, the transparent layer fills the reflective groove, and the surface of the transparent layer is flat.

[0015] In one embodiment, the step of forming an encapsulating adhesive layer on the surface of the lamp board prototype includes:

[0016] An encapsulating adhesive layer is formed on the surface of the LED substrate, wherein the thickness of the encapsulating adhesive layer is equal to the thickness of the LED chip;

[0017] The step of using a laser to cut a range corresponding to a preset position on the encapsulating adhesive layer after the encapsulating adhesive layer has cured, forming a reflective groove on the encapsulating adhesive layer, and placing a reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove includes:

[0018] After the encapsulating adhesive layer is cured, a laser is used to cut the area corresponding to the preset position of the encapsulating adhesive layer to form a reflective groove on the encapsulating adhesive layer;

[0019] A reflective material liquid is sprayed onto the surface of the encapsulating adhesive layer so that the reflective material liquid enters the reflective groove;

[0020] Before the reflective material liquid cures, a silicone scraper is used to scrape off the reflective material liquid from the surface of the encapsulating adhesive layer. The silicone scraper is tilted towards the surface of the encapsulating adhesive layer when it moves on the surface of the encapsulating adhesive layer.

[0021] A transparent adhesive layer is coated on the surface of the encapsulating adhesive layer.

[0022] In one embodiment, in the step of forming an encapsulating adhesive layer on the surface of the lamp board prototype, the encapsulating adhesive layer covers the outside of the LED chip, and a reflective material microcapsule is encapsulated within a predetermined position of the encapsulating adhesive layer, the predetermined position being located between each of the LED chips;

[0023] The step of using a laser to cut a range corresponding to a preset position on the encapsulating adhesive layer after the encapsulating adhesive layer has cured, forming a reflective groove on the encapsulating adhesive layer, and placing a reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove includes:

[0024] After the encapsulating adhesive layer is cured, a laser is used to cut the area corresponding to the preset position of the encapsulating adhesive layer to form a reflective groove on the encapsulating adhesive layer. The surface layer of the reflective material microcapsule located in the reflective groove is cut open so that the reflective material in the reflective material microcapsule is sprayed to the bottom of the reflective groove, forming a reflective layer at the bottom of the reflective groove.

[0025] In one embodiment, the encapsulating adhesive layer includes a first encapsulating adhesive layer and a second encapsulating adhesive layer;

[0026] The step of forming an encapsulating adhesive layer on the surface of the lamp board prototype includes:

[0027] A first encapsulation glue layer is formed on the surface of the LED board prototype, wherein the first encapsulation glue layer is disposed around the outside of the LED chip, and the thickness of the first encapsulation glue layer is less than the thickness of the LED chip;

[0028] A reflective material microcapsule is disposed at a first preset position in the first encapsulation gluon layer, wherein the first preset position is located between each of the LED chips;

[0029] A second encapsulation layer is formed on the surface of the first encapsulation layer and the reflective material microcapsule, and the second encapsulation layer covers the outside of each LED chip and each reflective material microcapsule;

[0030] The step of using a laser to cut a range corresponding to a preset position on the encapsulating adhesive layer after the encapsulating adhesive layer has cured, forming a reflective groove on the encapsulating adhesive layer, and placing a reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove includes:

[0031] After the second encapsulation gel layer is cured, a laser is used to cut the area corresponding to the second preset position of the second encapsulation gel layer to form a reflective groove on the second encapsulation gel layer. The surface of the reflective material microcapsule located in the reflective groove is cut open so that the reflective material in the reflective material microcapsule is sprayed into the reflective groove to form a reflective layer.

[0032] In one embodiment, the material of the first encapsulation gel layer is the same as the material of the second encapsulation gel layer.

[0033] In one embodiment, the projection of the first preset position onto the LED substrate falls within the projection range of the second preset position of the second encapsulation layer on the LED substrate. An LED LED substrate is manufactured using the LED substrate manufacturing method described in any of the above embodiments.

[0034] A backlight module includes the LED light panel described in any of the above embodiments.

[0035] 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

[0036] 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.

[0037] Figure 1 This is a schematic flowchart illustrating a method for manufacturing an LED light board according to one embodiment;

[0038] Figures 2A to 2F This is a schematic diagram of the manufacturing process of an LED light board according to one embodiment.

[0039] Explanation of reference numerals in the attached figures:

[0040] 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

[0041] 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.

[0042] 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.

[0043] like Figure 1 As shown, this is a method for manufacturing an LED light board according to an embodiment of the present invention, comprising:

[0044] Step 110: Install the LED chip on the substrate to obtain the lamp board prototype.

[0045] In this embodiment, a prototype lamp board is obtained. Specifically, solder is first applied to the pads on the substrate, then the pins of the LED chip are aligned with the pads, the LED chip is placed on the pads, and then the substrate is reflow soldered in a reflow oven to reflow solder the LED chip and the substrate, thereby fixing the LED chip on the substrate and obtaining the prototype lamp board.

[0046] Step 120: Form an encapsulating adhesive layer on the surface of the lamp board prototype.

[0047] In this embodiment, the encapsulating adhesive layer is also called a transparent adhesive layer. This encapsulating adhesive layer is made of a transparent material, such as transparent epoxy resin. The encapsulating adhesive layer covers the LED chip, and when the LED chip emits light, the emitted light passes through the encapsulating adhesive layer to reach the outside. In this embodiment, encapsulating adhesive is coated or sprayed onto the surface of the LED board prototype, covering the LED chip to form an encapsulating adhesive layer covering the LED chip on the surface of the LED board prototype.

[0048] Step 130: After the encapsulating adhesive layer is cured, a laser is used to cut the range corresponding to the preset position of the encapsulating adhesive layer to form a reflective groove on the encapsulating adhesive layer. A reflective material is placed at the bottom of the reflective groove, and a reflective layer is formed at the bottom of the reflective groove. The range corresponding to the preset position of the encapsulating adhesive layer is located between each of the LED chips.

[0049] In this embodiment, after the encapsulating adhesive layer cures, it is not easily deformed, and the thickness (height) of the formed layer is uniform, ensuring that the encapsulating adhesive layer covers the surface of the LED chip with uniform thickness and a smooth surface. Subsequently, laser cutting technology is used to cut the area corresponding to the preset positions of the encapsulating adhesive layer. It is worth mentioning that there are multiple preset positions of the encapsulating adhesive layer, and the area corresponding to each preset position is located between adjacent LED chips. In this way, the formed reflective groove is located between the LED chips. Subsequently, reflective material is sprayed or coated on the bottom of the reflective groove, and the reflective material forms a reflective layer at the bottom of the reflective groove. In one embodiment, the reflective material includes white oil.

[0050] It is worth mentioning that, compared to traditional LED light panels where white oil is coated on the substrate, in this embodiment, the reflective layer is set in the reflective groove, which can effectively prevent the reflective layer on the substrate from being affected by reflow soldering.

[0051] In other solutions, reflow soldering is performed first, followed by the application of a reflective layer (white oil). This approach requires a high-precision mask to precisely avoid the LED chips, resulting in higher costs. Furthermore, high-temperature curing after coating can cause cracking of the solder joints on the already soldered LED chips, compromising the stability of the LED board. Additionally, flux or oxide residues may remain on the substrate surface after reflow soldering, reducing the adhesion of the reflective layer. Therefore, in this embodiment, the reflective layer is placed within a reflective groove, effectively isolating it from the LED chips and preventing interference. This also avoids poor contact caused by cracked LED chip solder joints, and the reflective layer exhibits higher adhesion, effectively preventing it from detaching.

[0052] In the above embodiments, after the encapsulating adhesive layer is cured, a laser is used to cut the encapsulating adhesive layer to form a reflective groove, which effectively avoids deformation and uneven height caused by pressure on the encapsulating adhesive layer, making the thickness of the LED light board uniform, effectively improving the yield rate, and optimizing the light output effect.

[0053] In one embodiment, the step of distributing a reflective material at the bottom of the reflective groove and forming a reflective layer at the bottom of the reflective groove includes:

[0054] Using flow control inkjet printing technology, reflective material is sprayed onto the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove.

[0055] In this embodiment, fluidized inkjet printing technology combines microfluidics and inkjet printing. It achieves high-precision droplet generation and positioning through micron-level channels and nozzles, thus preventing spraying outside the reflective grooves and ensuring precise application of the reflective material to the bottom of the grooves. In one embodiment, fluidized inkjet printing technology uses a mask to spray the reflective material onto the bottom of the grooves, forming a reflective layer. Using a mask for spraying the reflective material allows for precise alignment with each groove, preventing obstruction of the LED chip's light emission.

[0056] 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 this embodiment, the sum of the height from 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. This ensures that the top surface of the reflective layer is located below the light-emitting direction of the LED chip, which helps the reflective layer to fully reflect the light from the LED chip.

[0057] In one embodiment, after the step of distributing reflective material at the bottom of the reflective groove and forming a reflective layer at the bottom of the reflective groove, the method further includes:

[0058] A transparent layer is coated on the surface of the encapsulating adhesive layer, the transparent layer fills the reflective groove, and the surface of the transparent layer is flat.

[0059] In this embodiment, the transparent layer can be made of the same material as the encapsulating adhesive layer. Besides encapsulating the LED chip, the encapsulating adhesive layer also transmits light. The transparent layer fills the emission groove, covers the surface of the reflective layer, and also covers the surface of the encapsulating adhesive layer, making the surface of the LED light board smooth and resulting in more uniform light emission. In one embodiment, the transparent layer is made of transparent epoxy resin.

[0060] In one embodiment, the step of forming an encapsulating adhesive layer on the surface of the LED substrate includes: forming an encapsulating adhesive layer on the surface of the LED substrate, wherein the thickness of the encapsulating adhesive layer is equal to the thickness of the LED chip;

[0061] The step of using a laser to cut a range corresponding to a preset position on the encapsulating adhesive layer after the encapsulating adhesive layer has cured, forming a reflective groove on the encapsulating adhesive layer, and placing a reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove includes:

[0062] After the encapsulating adhesive layer is cured, a laser is used to cut the area corresponding to the preset position of the encapsulating adhesive layer to form a reflective groove on the encapsulating adhesive layer;

[0063] A reflective material liquid is sprayed onto the surface of the encapsulating adhesive layer so that the reflective material liquid enters the reflective groove;

[0064] Before the reflective material liquid cures, a silicone scraper is used to scrape off the reflective material liquid from the surface of the encapsulating adhesive layer. The silicone scraper is tilted towards the surface of the encapsulating adhesive layer when it moves on the surface of the encapsulating adhesive layer.

[0065] A transparent adhesive layer is coated on the surface of the encapsulating adhesive layer.

[0066] In this embodiment, after the encapsulating adhesive layer is cured and formed, its thickness on the substrate is the same as the height of the LED chip on the substrate. Thus, the surface of the encapsulating adhesive layer is flush with the top surface of the LED chip. After the encapsulating adhesive layer has cured, it is cut using a laser to form multiple reflective grooves. Subsequently, a reflective material liquid, such as white oil, is sprayed onto the entire surface of the encapsulating adhesive layer. The reflective material liquid on the surface of the encapsulating adhesive layer is then scraped off using a silicone scraper. The silicone scraper has excellent elasticity and antistatic properties, and can adapt to minor unevenness on the surface of the encapsulating adhesive layer, avoiding hard contact. The scratches that cause the encapsulation adhesive layer surface allow for thorough adhesion to the surface, effectively scraping away the reflective material liquid. Specifically, the angle between the silicone squeegee and the encapsulation adhesive layer surface is 15° to 30° along the squeegee's forward direction. It's worth noting that if the angle is too large, the friction is too high, causing the squeegee to vibrate, leading to edge buildup and deformation of the encapsulation adhesive layer. Conversely, if the angle is too small, the shearing force is insufficient, resulting in a large amount of reflective material liquid residue. Therefore, in this embodiment, the silicone squeegee is tilted along its forward direction, maintaining an angle of 15° to 30° with the encapsulation adhesive layer surface. This effectively protects the encapsulation adhesive layer and thoroughly removes the reflective material liquid.

[0067] In this embodiment, since the surface of the encapsulating adhesive layer is flush with the top surface of the LED chip, the surface of the encapsulating adhesive layer remains flat, which facilitates the scraping out of the reflective material liquid. After the reflective material liquid on the surface of the encapsulating adhesive layer is scraped off, the reflective material liquid in the reflective groove remains, allowing the reflective material liquid to solidify within the reflective groove to form a reflective layer. Subsequently, a transparent layer is applied to the surface of the encapsulating adhesive layer. The transparent layer can be made of the same material as the encapsulating adhesive layer. The transparent layer is used to fill the reflective groove, covering the surface of the reflective layer and the surface of the encapsulating adhesive layer, making the surface of the LED light board flat and resulting in more uniform light emission from the LED light board. In one embodiment, the transparent layer is made of transparent epoxy resin.

[0068] To reduce the height of the reflective material liquid, thereby ensuring the height of the formed reflective layer is lower than the surface of the encapsulating adhesive layer and the height of the LED chip, in one embodiment, the surface of the silicone scraper is provided with multiple raised dots, each with a diameter of 50-80 μm and a thickness of 30-90 μm. A reflective receiving groove is formed at the bottom of the reflective groove, creating a stepped structure. The reflective material liquid fills the reflective groove and the reflective receiving groove. When the silicone scraper passes over it, the raised dots penetrate into the reflective groove, scraping away some of the reflective material liquid, thus reducing its height. Because of the reflective receiving groove at the bottom of the reflective groove, any remaining reflective material liquid can be retained within it, preventing it from being completely scraped away. This allows for a reduction in the height of the reflective material liquid while preventing its complete removal. To further reduce the height of the reflective material liquid within the reflective groove and ensure sufficient removal of the reflective material liquid from the surface of the encapsulating adhesive layer, the silicone scraper can be used repeatedly.

[0069] In this embodiment, because the liquid level of the reflective material drops below the surface of the encapsulating adhesive layer, the height of the formed reflective layer is lower than the height of the LED chip, thereby achieving a good reflection effect.

[0070] In one embodiment, in the step of forming an encapsulating adhesive layer on the surface of the lamp board prototype, the encapsulating adhesive layer covers the outside of the LED chip, and a reflective material microcapsule is encapsulated within a predetermined position of the encapsulating adhesive layer, the predetermined position being located between each of the LED chips;

[0071] The step of using a laser to cut a range corresponding to a preset position on the encapsulating adhesive layer after the encapsulating adhesive layer has cured, forming a reflective groove on the encapsulating adhesive layer, and placing a reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove includes:

[0072] After the encapsulating adhesive layer is cured, a laser is used to cut the area corresponding to the preset position of the encapsulating adhesive layer to form a reflective groove on the encapsulating adhesive layer. The surface layer of the reflective material microcapsule located in the reflective groove is cut open so that the reflective material in the reflective material microcapsule is sprayed to the bottom of the reflective groove, forming a reflective layer at the bottom of the reflective groove.

[0073] In this embodiment, a reflective material microcapsule is pre-encapsulated within a predetermined location in the encapsulating adhesive layer. This microcapsule contains reflective material. When the encapsulating adhesive layer is cut using a laser, the cut is first made around the edge of the area corresponding to the predetermined location, and then gradually moves inward to form a reflective groove. Subsequently, the surface of the reflective material microcapsule is cut open using a laser, causing the reflective material inside the microcapsule to be ejected into the bottom of the reflective groove, thus forming a reflective layer at the bottom of the groove. It is worth noting that because the reflective material microcapsule is pre-placed within the encapsulating adhesive layer, the reflective material capsule can be directly cut open using laser cutting, eliminating the need for an additional reflective material coating process, effectively improving efficiency and reducing costs.

[0074] It is worth mentioning that the reflective material microcapsules are filled with reflective material, such as white oil or a nano-TiO2 (titanium dioxide) suspension. In this embodiment, the LED chip size is 100-200 μm, the LED chip thickness is 80-150 μm, the distance between LED chips is 100-150 μm, the diameter of the reflective material microcapsules is 30-50 μm, and the diameter of the reflective groove is 50-90 μm, resulting in a reflective layer thickness of 3-35 μm. It is also worth noting that a process tolerance of approximately 5-10 μm needs to be allowed for the diameter of the reflective groove, which is caused by errors from laser cutting or thermal deformation of the material. For example, if the diameter of the reflective material microcapsules is 50 μm and the diameter of the reflective groove is set to 60 μm, it can accommodate a positioning deviation of ±5 μm, and the reflective layer thickness is 23 μm.

[0075] In one embodiment, such as Figure 2D As shown, the encapsulating adhesive layer includes a first encapsulating adhesive layer and a second encapsulating adhesive layer; please refer to both. Figures 2B to 2E As shown, the step of forming an encapsulating adhesive layer on the surface of the lamp board prototype includes:

[0076] A first encapsulation glue layer is formed on the surface of the LED board prototype, wherein the first encapsulation glue layer is disposed around the outside of the LED chip, and the thickness of the first encapsulation glue layer is less than the thickness of the LED chip;

[0077] A reflective material microcapsule is disposed at a first preset position in the first encapsulation gluon layer, wherein the first preset position is located between each of the LED chips;

[0078] A second encapsulation layer is formed on the surface of the first encapsulation layer and the reflective material microcapsule, and the second encapsulation layer covers the outside of each LED chip and each reflective material microcapsule;

[0079] The step of using a laser to cut a range corresponding to a preset position on the encapsulating adhesive layer after the encapsulating adhesive layer has cured, forming a reflective groove on the encapsulating adhesive layer, and placing a reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove includes:

[0080] After the second encapsulation gel layer is cured, a laser is used to cut the area corresponding to the second preset position of the second encapsulation gel layer to form a reflective groove on the second encapsulation gel layer. The surface of the reflective material microcapsule located in the reflective groove is cut open so that the reflective material in the reflective material microcapsule is sprayed into the reflective groove to form a reflective layer.

[0081] It's worth noting that the cutting depth of the encapsulating adhesive layer is greater than or equal to the thickness of the second encapsulating adhesive layer. This allows the reflective material capsule to be exposed, facilitating laser cutting. Furthermore, it ensures that the bottom height of the reflective groove is less than the top height of the LED chip, resulting in better reflection from the reflective layer at the bottom of the groove. Additionally, during laser cutting of the encapsulating adhesive layer, it vaporizes, while the reflective material, containing metal particles such as nano-sized titanium dioxide, effectively avoids vaporization. Therefore, controlling the laser temperature to vaporize the encapsulating adhesive layer without reaching the vaporization temperature of the metal particles effectively cuts the encapsulating adhesive layer while preventing the reflective material from vaporizing.

[0082] In this embodiment, a transparent colloid is first coated or sprayed onto the substrate surface to form a first encapsulation layer. The thickness of this first encapsulation layer is less than the thickness of the LED chip, allowing the reflective material microcapsules on the first encapsulation layer to be located below the LED chip. The first encapsulation layer covers the surface of the substrate and surrounds the outer side of the LED chip. Notably, this first encapsulation layer may or may not cover the top surface of the LED chip. When coating or spraying the transparent colloid, there is no need to avoid the LED chip, thus effectively improving the formation efficiency of the first encapsulation layer. Subsequently, reflective material microcapsules are placed on the first encapsulation layer, positioned between adjacent LED chips. Then, a transparent colloid is coated or sprayed onto the surface of the first encapsulation layer, covering the surface of the reflective material microcapsules to form a second encapsulation layer covering the outside of the reflective material microcapsules. This second encapsulation layer also covers the top surface of the LED chip. After curing, the top surface of the second encapsulation layer is flat. This results in a higher overall flatness of the encapsulation layer.

[0083] In this embodiment, the thickness of the first encapsulation layer is 60~100μm, which makes the thickness of the first encapsulation layer less than the thickness of the LED chip. The thickness of the second encapsulation layer is 90~200μm, and the depth of the reflective groove formed downward along the surface of the second encapsulation layer is 90~220μm. Since the depth of the reflective groove is much greater than the diameter of the reflective material microcapsule, the range of the reflective material liquid can be limited, preventing the reflective material liquid from spreading to areas outside the reflective groove.

[0084] In this embodiment, by placing reflective material microcapsules on the first encapsulation adhesive layer and then coating or spraying a second encapsulation adhesive layer, the reflective material microcapsules are pre-embedded in the second encapsulation adhesive layer. After cutting the encapsulation adhesive layer to form a reflective groove, the reflective material microcapsules are cut open. The reflective groove formed by the cutting restricts the range of reflective material ejected from the reflective material microcapsules, preventing the reflective material from spreading to areas outside the reflective groove and avoiding blocking the light output of the LED chip.

[0085] It is worth mentioning that, since the reflective material microcapsules are located within the range corresponding to the first preset position and the second preset position, this method is more efficient than the method of first cutting to form a reflective groove and then spraying and coating the reflective layer on the bottom of the reflective groove. On the one hand, since the first preset position is within the range corresponding to the second preset position, the accuracy of the first preset position does not need to be very high, only within the range corresponding to the second preset position. Furthermore, the diffusion of the reflective material can be restricted by the reflective groove formed by cutting, so that the reflective layer is formed within the reflective groove. In the method of spraying the reflective layer within the reflective groove, it is necessary to accurately position the reflective groove so that the nozzle is accurately aligned with the reflective groove. With the steps being the same, the accuracy requirement is lower, thus effectively improving efficiency and reducing costs. On the other hand, for accurate spraying, a mask is needed to spray the reflective material within the reflective groove. However, in this embodiment, no mask is needed to place the reflective material microcapsules. Therefore, placing the reflective material microcapsules on the surface of the first encapsulation adhesive layer is less difficult than spraying the reflective material within the reflective groove. Moreover, it effectively avoids irregular deformation and local protrusions caused by the pressure of the encapsulation adhesive layer, effectively maintaining the flatness and stability of the encapsulation adhesive layer.

[0086] To place the reflective material microcapsules on the surface of the first encapsulation layer, in one embodiment, the reflective material microcapsules are further dispersed in liquid epoxy resin. The microcapsules, coated with liquid epoxy resin, are then positioned at a first predetermined location using inkjet printing. After the liquid epoxy resin cures, the reflective material microcapsules are fixed to the surface of the first encapsulation layer. Since the epoxy resin on the surface of the reflective material microcapsules is made of the same material as both the first and second encapsulation layers, the curing of the epoxy resin allows the reflective material microcapsules to be fixed to the surface of the first encapsulation layer. Furthermore, after the second encapsulation layer is applied, the epoxy resin on the surface of the reflective material microcapsules and the second encapsulation layer become integrated, facilitating subsequent processing.

[0087] In order to ensure that the microcapsules of reflective material can be accurately sprayed to the bottom of the reflective groove after being cut, in one embodiment, the bottom of each reflective groove gradually slopes towards the substrate from the middle to the outer edge, that is, the depth of the reflective groove gradually increases from the middle to the outer edge, so that the bottom of the reflective groove is outward and downward. This facilitates the diffusion of the reflective material liquid and covers the bottom of the reflective groove.

[0088] In one embodiment, the material of the first encapsulation gel layer is the same as the material of the second encapsulation gel layer.

[0089] In this embodiment, both the first and second encapsulating adhesive layers are made of epoxy resin. Using the same material results in stronger adhesion between the first and second encapsulating adhesive layers, leading to higher overall strength of the encapsulating adhesive layers and better overall light transmittance.

[0090] In one embodiment, the projection of the first preset position on the lamp board prototype is located within the projection range of the second preset position of the second encapsulation glue layer on the lamp board prototype.

[0091] In this embodiment, the first preset position on the first encapsulation gel layer is the position where the reflective material microcapsule is placed, and the range corresponding to the second preset position on the second encapsulation gel layer is the range of the reflective groove. Therefore, the first preset position is located within the range corresponding to the second preset position in the direction perpendicular to the substrate, which enables the laser cutting to form a reflective groove around the position where the reflective material microcapsule is located, and makes the reflective material microcapsule located in the reflective groove.

[0092] In one embodiment, the reflective material microcapsule includes a surface layer, a reflective material liquid, and a vaporization pressurization liquid, wherein the surface layer covers the outside of the reflective material liquid and the vaporization pressurization liquid.

[0093] 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.

[0094] 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.

[0095] 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.

[0096] In one embodiment, an LED light board and a method for manufacturing the same are provided, comprising:

[0097] Step 1, as follows Figure 2A As shown, LED chip 210 is mounted on substrate 200 to obtain a prototype lamp board.

[0098] Step two, as Figure 2BAs 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.

[0099] 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.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] In one embodiment, a backlight module is provided, including the LED light panel described in any of the above embodiments.

[0105] 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.

[0106] 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.

[0107] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for manufacturing an LED light board, characterized in that, include: The LED chips are mounted on the substrate to obtain the lamp board prototype. An encapsulating adhesive layer is formed on the surface of the lamp board prototype; After the encapsulating adhesive layer is cured, a laser is used to cut the area corresponding to the preset position of the encapsulating adhesive layer to form a reflective groove on the encapsulating adhesive layer. A reflective material is placed at the bottom of the reflective groove, and a reflective layer is formed at the bottom of the reflective groove. The area corresponding to the preset position of the encapsulating adhesive layer is located between each of the LED chips. In the step of forming an encapsulating adhesive layer on the surface of the lamp board prototype, the encapsulating adhesive layer covers the outside of the LED chip, and a microcapsule of reflective material is encapsulated in a preset position within the encapsulating adhesive layer, the preset position being located between each of the LED chips; The step of using a laser to cut a range corresponding to a preset position on the encapsulating adhesive layer after the encapsulating adhesive layer has cured, forming a reflective groove on the encapsulating adhesive layer, and placing a reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove includes: After the encapsulating adhesive layer is cured, a laser is used to cut the area corresponding to the preset position of the encapsulating adhesive layer to form a reflective groove on the encapsulating adhesive layer. The surface of the reflective material microcapsule located in the reflective groove is cut open so that the reflective material in the reflective material microcapsule is sprayed to the bottom of the reflective groove, forming a reflective layer at the bottom of the reflective groove. The reflective material contains a nano-titanium dioxide suspension.

2. The method for manufacturing an LED light board according to claim 1, characterized in that, After the step of setting a reflective material at the bottom of the reflective groove and forming a reflective layer at the bottom of the reflective groove, the method further includes: A transparent layer is coated on the surface of the encapsulating adhesive layer, the transparent layer fills the reflective groove, and the surface of the transparent layer is flat.

3. The method for manufacturing an LED light board according to claim 1, characterized in that, The encapsulating adhesive layer includes a first encapsulating adhesive sub-layer and a second encapsulating adhesive layer; The step of forming an encapsulating adhesive layer on the surface of the lamp board prototype includes: A first encapsulation glue layer is formed on the surface of the LED board prototype, wherein the first encapsulation glue layer is disposed around the outside of the LED chip, and the thickness of the first encapsulation glue layer is less than the thickness of the LED chip; A reflective material microcapsule is disposed at a first preset position in the first encapsulation gluon layer, wherein the first preset position is located between each of the LED chips; A second encapsulation layer is formed on the surface of the first encapsulation layer and the reflective material microcapsule, and the second encapsulation layer covers the outside of each LED chip and each reflective material microcapsule; The step of using a laser to cut a range corresponding to a preset position on the encapsulating adhesive layer after the encapsulating adhesive layer has cured, forming a reflective groove on the encapsulating adhesive layer, and placing a reflective material at the bottom of the reflective groove to form a reflective layer at the bottom of the reflective groove includes: After the second encapsulation gel layer is cured, a laser is used to cut the area corresponding to the second preset position of the second encapsulation gel layer to form a reflective groove on the second encapsulation gel layer. The surface of the reflective material microcapsule located in the reflective groove is cut open so that the reflective material in the reflective material microcapsule is sprayed into the reflective groove to form a reflective layer.

4. The method for manufacturing an LED light board according to claim 3, characterized in that, The material of the first encapsulation layer is the same as the material of the second encapsulation layer.

5. The method for manufacturing an LED light board according to claim 3, characterized in that, The projection of the first preset position on the lamp board prototype is located within the projection range of the second preset position of the second encapsulation glue layer on the lamp board prototype.

6. An LED light panel, characterized in that, It is manufactured using the LED light board manufacturing method described in any one of claims 1-5.

7. A backlight module, characterized in that, Includes the LED light panel as described in claim 6.

Images