Fluorescent epoxy adhesive film for epoxy CSP (Chip Scale Package) lamp bead as well as preparation method and application of fluorescent epoxy adhesive film

Abstract

The invention relates to the technical field of CSP (Chip Scale Package), in particular to a fluorescent epoxy adhesive film for an epoxy CSP lamp bead as well as a preparation method and application of the fluorescent epoxy adhesive film. The transparent liquid epoxy glue at least comprises the following preparation raw materials: an epoxy resin solution, a curing agent, a defoaming agent, an antioxidant, an anti-precipitating agent and a catalyst, the epoxy resin solution at least comprises organic silicon modified epoxy resin, a trifunctional epoxy compound and epoxy resin containing an alicyclic structure; the melt viscosity of the epoxy resin solution at 150 DEG C is 400-1000 Pa.s, the problems that existing organic silica gel water is low in hardness during actual packaging and low in bonding force with subsequent epoxy resin are solved, the product yield of subsequently prepared CSP lamp beads is increased, and meanwhile the aging resistance of the CSP lamp beads is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of CSP, in particular to a fluorescent epoxy adhesive film for epoxy CSP lamp beads and a preparation method and application thereof. Background Art

[0002] With the development of LED display application industry, the shooting effect of RGB LED virtual studio can no longer meet the production requirements of high-quality film and television dramas. The current RGB LED virtual studio can only display three colors: red, green and blue, and cannot adjust the brightness and color temperature of white light, resulting in inconsistent lighting conditions between real scenes and virtual scenes, affecting the restoration and naturalness of skin color. In order to solve the problems of RGB LED virtual studio at this stage, industry technicians added a high color rendering index inverted white light CSP lamp bead to the inverted RGB LED lamp bead to develop the RGBW virtual studio.

[0003] At present, most white light CSP lamp beads are obtained by using blue light chips to excite yellow phosphors. In order to meet the low light decay requirements of white light lamp beads, the industry usually uses silicone resin materials to encapsulate blue light chips. However, due to the low hardness of silicone resin, the encapsulation layer is easily damaged after vibration sorting, which greatly reduces the product yield of white light lamp beads. In order to avoid the problem of dead lights on the display screen due to external force collision, RGB virtual studios prefer to use epoxy resin materials with greater hardness to encapsulate chips. Under this premise, if organic silicone water is used to encapsulate white light CSP lamp beads, the problem of epoxy-organic silicone interface peeling will occur, because the adhesion between silicone resin and epoxy resin is low. After PCT aging (high-voltage accelerated aging), the organic silicone white light lamp beads and the outer layer of epoxy resin are easily peeled off. For example, the Chinese patent (publication number CN 113659053 A) discloses a manufacturing process for a CSP lamp bead encapsulation structure, which uses silicone, silicone or epoxy resin for encapsulation, which cannot effectively solve the above problems. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a fluorescent epoxy film for epoxy CSP lamp beads, which overcomes the problems of low hardness of the existing organic silicone water during actual packaging and low bonding strength with the subsequent epoxy resin, improves the product yield of the subsequently prepared CSP lamp beads while ensuring their aging resistance.

[0005] On one hand, the present invention provides a fluorescent epoxy adhesive film for epoxy CSP lamp beads, wherein the raw materials for preparing the fluorescent epoxy adhesive film at least include: transparent liquid epoxy adhesive and fluorescent powder; the raw materials for preparing the transparent liquid epoxy adhesive at least include: epoxy resin solution, curing agent, defoaming agent, antioxidant, anti-precipitation agent and catalyst; The epoxy resin solution at least comprises an organosilicon-modified epoxy resin, a trifunctional epoxy compound, and an epoxy resin containing an alicyclic structure; the epoxy resin solution has a melting viscosity of 400-1000 Pa.s at 150°C.

[0006] As a preferred technical solution, the epoxy resin solution has a melt viscosity of 500-800 Pa.s at 150°C, preferably 600±50 Pa.s.

[0007] As a preferred technical solution, the mass ratio of the silicone-modified epoxy resin, the trifunctional epoxy compound, and the epoxy resin containing an alicyclic structure is 1:(0.5-2):(2-5), preferably 1:1:(2-4), and most preferably 1:1:3.

[0008] As a preferred technical solution, the silicone-modified epoxy resin is Dow EP2601 silicone-modified epoxy resin, the trifunctional epoxy compound is tri(2,3-epoxypropyl)isocyanurate, model Tepic-s (Nissan Chemical), and the epoxy resin containing an alicyclic structure is CELLOXIDE 2021P liquid aliphatic epoxy resin.

[0009] As a preferred technical solution, the raw materials for preparing the transparent liquid epoxy adhesive include at least 80-120 parts of epoxy resin solution, 60-90 parts of curing agent, 1-2 parts of defoaming agent, 0.5-2 parts of antioxidant, 1-3 parts of anti-precipitation agent, and 0.1-1 parts of catalyst, by weight.

[0010] As a preferred technical solution, the amount of phosphor added to the fluorescent epoxy film is 20-80wt%, preferably 45-60wt%.

[0011] The present invention optimizes the epoxy resin solution including organosilicon-modified epoxy resin, trifunctional epoxy compound, and epoxy resin containing alicyclic structure, further optimizes the epoxy resin solution to have a melt viscosity of 400-1000Pa.s at 150°C, and cooperates with other raw materials to meet the application requirements of high hardness, low light decay, and high adhesion during the subsequent preparation of CSP lamp beads, and has excellent stability. Furthermore, by controlling the mass ratio of transparent liquid epoxy glue and phosphor, adjustable luminous flux and color temperature are obtained, the content of phosphor in transparent liquid epoxy glue is increased, the luminous flux is increased, and the color temperature is reduced, especially the amount of phosphor added in the fluorescent epoxy film is controlled to be 45-60wt%, ensuring the subsequent applicability of the fluorescent epoxy film in epoxy CSP.

[0012] As a preferred technical solution, the curing agent is at least one of methyltetrahydrophthalic anhydride, maleic anhydride, tetrahydrophthalic anhydride, and pyromellitic dianhydride, preferably methyltetrahydrophthalic anhydride.

[0013] As a preferred technical solution, the defoamer is a silicone defoamer, preferably BYK-024 defoamer.

[0014] As a preferred technical solution, the antioxidant is at least one of antioxidant 1010, antioxidant 168, antioxidant 626, and antioxidant 1135, preferably antioxidant 1010.

[0015] As a preferred technical solution, the anti-precipitation agent is H-18 anti-precipitation powder.

[0016] As a preferred technical solution, the catalyst is triphenylphosphine.

[0017] As a preferred technical solution, the phosphor is Intermetallic YAG-04 phosphor.

[0018] Another aspect of the present invention provides a method for preparing a fluorescent epoxy film for epoxy CSP lamp beads, which comprises at least the following steps: (1) intermittently stirring an organosilicon-modified epoxy resin, a trifunctional epoxy compound, or an epoxy resin containing an alicyclic structure at 140-160° C. for 1-3 hours to obtain an epoxy resin solution; (2) Add defoamer, antioxidant, anti-precipitant and curing agent to the epoxy resin solution in sequence, stir continuously for 60-120 minutes at 90-110°C, cool to 70-80°C and add catalyst, stir manually for 5-15 minutes while keeping warm, stir for 3-8 minutes with a dispersing disk at a speed of 500-800 rpm, and finally control the vacuum degree and stir at a speed of 800-1200 rpm for 3-5 minutes to obtain a transparent liquid epoxy adhesive; (3) Adding fluorescent powder to the transparent liquid epoxy glue, stirring and degassing to obtain the fluorescent epoxy glue; (4) Coat the fluorescent epoxy adhesive on the release film, place it in a 70-90°C forced air drying oven, and bake it for 20-40 minutes to obtain a fluorescent epoxy adhesive film in the B-stage state.

[0019] The fluorescent epoxy adhesive obtained in the present invention is placed in a constant temperature heating jacket at 50° C. for storage and standby use, ensuring that it is used up within 3-5 hours.

[0020] Regarding the explanation of the "B-Stage state" in the present invention, the curing reaction of thermosetting resin can be divided into three stages: A / B / C: A Stage: The resin is in the early stages of the reaction. Due to the low degree of polymerization, the molecular weight is still very low and the material is in a liquid state.

[0021] B Stage: The resin continues to react, and most of the structure is linear and partially cross-linked. The molecular weight is large enough to be semi-cured. At this stage, the material can be dissolved by specific solvents and can flow or melt at a specific temperature. The reaction of some resins is not obvious at this stage.

[0022] C Stage: This stage is the late stage of the resin reaction. The molecular structure presents a network cross-linked structure. The material can no longer be heated and melted, nor can it be dissolved by solvents. It is the final state of the material after the curing reaction. The surface is usually non-sticky and has a stable Tg.

[0023] Preparation of epoxy CSP lamp beads, the epoxy CSP lamp bead structure includes a chip, an adhesive layer, a solid crystal plate, and a fluorescent epoxy film. The adhesive layer is attached to the upper surface of the solid crystal plate, the chip is fixed on the upper surface of the adhesive layer, and the fluorescent epoxy film covers the exposed surface of the chip.

[0024] As a preferred technical solution, the thickness of the chip is 50-150 μm, and the chip size is (4-10)×(5-20) mil. Preferably, the thickness of the chip is 80-120 μm, and the chip size is (4-6)×(8-20) mil.

[0025] The preparation process of the epoxy CSP lamp beads at least includes the following steps: S1. Die bonding: The adhesive layer is adhered to the substrate, and the chip is bonded in a step of 0.7*0.4mm. The die bonding area is 35*24mm. S2. Lamination: Place the fluorescent epoxy film on the die-bonding board, and place a square gasket with a thickness of 238μm and a functional area size of 60*60mm on the fluorescent epoxy film. Place it in a vacuum laminating machine at a temperature of 140-160℃ for 240-360s to complete the chip packaging.

[0026] S3, post-curing: then place in a 140-160℃ oven and bake for 3-5 hours to complete the post-curing of the fluorescent epoxy film, and then cut and mold it to obtain.

[0027] The low light decay and high hardness epoxy CSP lamp beads provided by the present invention improve the overall stability of the RGBW lamp beads, thereby improving the picture quality and visual effects of virtual shooting, and the production process is simple, easy to realize large-scale industrial production, and has high market promotion value.

[0028] The epoxy CSP lamp beads provided by the present invention can obtain epoxy CSP lamp beads with different brightness and color temperature by adjusting the chip size and thickness, and the larger the chip size and thickness, the lower the brightness of the epoxy CSP lamp beads and the higher the color temperature.

[0029] Beneficial Effects 1. The present invention provides a fluorescent epoxy film for epoxy CSP lamp beads, which overcomes the problems of low hardness of the existing organic silicone water during actual packaging and low bonding strength with the subsequent epoxy resin, improves the product yield of the subsequently prepared CSP lamp beads while ensuring its aging resistance.

[0030] 2. The present invention optimizes the epoxy resin solution including silicone-modified epoxy resin, trifunctional epoxy compound, and epoxy resin containing alicyclic structure, further optimizes the melt viscosity of the epoxy resin solution at 150°C to 400-1000 Pa.s, and combines other raw materials to meet the application requirements of high hardness, low light decay and high adhesion in the subsequent preparation of CSP lamp beads, and has excellent stability.

[0031] 3. The present invention obtains adjustable luminous flux and color temperature by controlling the mass ratio of transparent liquid epoxy glue and phosphor, increases the content of phosphor in transparent liquid epoxy glue, increases luminous flux and reduces color temperature, and especially controls the addition amount of phosphor in fluorescent epoxy film to 45-60wt%, thereby ensuring the applicability of fluorescent epoxy film in subsequent epoxy CSP.

[0032] 4. The low light decay and high hardness epoxy CSP lamp beads provided by the present invention improve the overall stability of the RGBW lamp beads, thereby improving the picture quality and visual effects of virtual shooting. In addition, the production process is simple and easy to realize large-scale industrial production, and has a high market promotion value.

[0033] 5. The epoxy CSP lamp beads provided by the present invention can obtain epoxy CSP lamp beads with different brightness and color temperature by adjusting the chip size and thickness. The larger the chip size and thickness, the lower the brightness of the epoxy CSP lamp beads and the higher the color temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is the structure of the epoxy CSP lamp bead provided in Example 1, in which 1 is the chip, 2 is the bonding layer, 3 is the die-bonding plate, and 4 is the fluorescent epoxy film.

[0035] Figure 2 This is a real picture of the sample of the fluorescent epoxy adhesive provided in Example 1 during hardness test.

[0036] Figure 3 , Figure 4 They are the bonding force test result diagrams of Example 1 and Comparative Example 1 respectively.

[0037] Figure 5 , Figure 6 They are the stability test result diagrams of Example 1 and Comparative Example 2 respectively. DETAILED DESCRIPTION

[0038] Example 1 Embodiment 1 of the present invention provides a fluorescent epoxy film for epoxy CSP lamp beads, wherein the raw materials for preparing the fluorescent epoxy film include: transparent liquid epoxy glue and fluorescent powder; in parts by weight, the raw materials for preparing the transparent liquid epoxy glue include: 100 parts of epoxy resin solution, 75.25 parts of curing agent, 1.50 parts of defoaming agent, 1.00 parts of antioxidant, 1.50 parts of anti-precipitation agent, and 0.50 parts of catalyst; The epoxy resin solution includes silicone-modified epoxy resin, trifunctional epoxy compound, and epoxy resin containing alicyclic structure; the mass ratio of the silicone-modified epoxy resin, trifunctional epoxy compound, and epoxy resin containing alicyclic structure is 1:1:3; the melt viscosity of the epoxy resin solution at 150°C is 600±50 Pa.s.

[0039] The silicone-modified epoxy resin is Dow EP2601 silicone-modified epoxy resin, the trifunctional epoxy compound is tri(2,3-epoxypropyl)isocyanurate, model Tepic-s (Nissan Chemical), and the epoxy resin containing an alicyclic structure is CELLOXIDE 2021P liquid aliphatic epoxy resin.

[0040] The amount of phosphor added to the fluorescent epoxy film is 60wt%.

[0041] The curing agent is methyltetrahydrophthalic anhydride.

[0042] The defoamer is BYK-024 defoamer.

[0043] The antioxidant is antioxidant 1010.

[0044] The anti-precipitation agent is H-18 anti-precipitation powder.

[0045] The catalyst is triphenylphosphine.

[0046] The phosphor is Intermetallic YAG-04 phosphor.

[0047] Another aspect of the present invention provides a method for preparing a fluorescent epoxy film for epoxy CSP lamp beads, comprising the following steps: (1) an epoxy resin modified with silicone, a trifunctional epoxy compound, and an epoxy resin containing an alicyclic structure are intermittently stirred at 150° C. for 2 h to obtain an epoxy resin solution; (2) Add an antifoaming agent, an antioxidant, an anti-settling agent, and a curing agent to the epoxy resin solution in sequence. After continuously stirring for 90 min under the condition of 100 °C, cool down to 80 °C and then add a catalyst. After manual stirring for 10 min while maintaining the temperature, stir for 5 min with a dispersion disc at a rotational speed of 600 rpm. Finally, control the vacuum degree to -98 Kpa and stir for 3 min at a rotational speed of 1000 rpm to obtain a transparent liquid epoxy adhesive. (3) Add phosphor powder to the transparent liquid epoxy adhesive, stir with a glass rod by hand for 5 min, and then place it in a double planetary vacuum degassing machine. Stir for 3 min under a vacuum degree of -98 KPa and at 1000 rpm to obtain a fluorescent epoxy adhesive. (4) Coat the fluorescent epoxy adhesive on a PET release film, place it in a forced air drying oven at 80 °C, and bake for 30 min to obtain a fluorescent epoxy adhesive film in the B-stage state (with a size of 55×55 mm and a thickness of 287 μm).

[0048] See Figure 1 , the third aspect of Example 1 of the present invention provides an application of a fluorescent epoxy adhesive film for epoxy CSP lamp beads, which is applied to the preparation of epoxy CSP lamp beads. The structure of the epoxy CSP lamp bead includes a chip 1, an adhesive layer 2, a die bonding plate 3, and a fluorescent epoxy adhesive film 4. The adhesive layer 2 is attached and bonded to the upper surface of the die bonding plate 3, the chip 1 is fixed on the upper surface of the adhesive layer 2, and the fluorescent epoxy adhesive film 4 covers the exposed surface of the chip 1.

[0049] The thickness of the chip is 80 μm, and the chip size is 4×8 mil.

[0050] The preparation process of the epoxy CSP lamp bead includes the following steps: S1, Die bonding: Adhere the adhesive layer to the substrate, and perform die bonding on the chip with a step of 0.7*0.4 mm. The die bonding area is 35*24 mm; S2, Pressing: Place the fluorescent epoxy adhesive film on the die bonding plate, place a square gasket with a thickness of 238 μm and a functional area size of 60*60 mm on the fluorescent epoxy adhesive film, and place it in a vacuum pressing machine at 150 °C. The pressing time is 300 s to complete the encapsulation of the chip.

[0051] S3, Post-curing: Then place it in an oven at 150 °C and bake for 4 hours to complete the post-curing of the fluorescent epoxy adhesive film; S4, Lamp bead post-treatment: Cut with a knife with a thickness of 100 um at a knife speed of 80 mm / s to obtain white light epoxy CSP lamp beads with a size of 0.6*0.3 mm.

[0052] Example 2 Embodiment 2 of the present invention provides a fluorescent epoxy film for epoxy CSP lamp beads, and a preparation method and application thereof. The specific implementation manner is the same as that of Embodiment 1, except that the amount of phosphor added to the fluorescent epoxy film is 45wt%.

[0053] Example 3 Embodiment 3 of the present invention provides a fluorescent epoxy film for epoxy CSP lamp beads and a preparation method and application thereof. The specific implementation method is the same as that of Embodiment 1, except that the thickness of the chip is 120 μm and the chip size is 6×20 mil.

[0054] Comparative Example 1 Comparative Example 1 of the present invention provides a fluorescent adhesive film for CSP lamp beads, and a preparation method and application thereof. The specific implementation method is the same as that of Example 1, except that the transparent liquid epoxy adhesive is replaced by Dow Corning® OE-7842 organic silicone.

[0055] Comparative Example 2 Comparative Example 2 of the present invention provides a fluorescent epoxy film for epoxy CSP lamp beads and a preparation method and application thereof. The specific implementation method is the same as that of Example 1, except that the preparation method of the fluorescent epoxy film for epoxy CSP lamp beads is: (1) an epoxy resin modified with silicone, a trifunctional epoxy compound, and an epoxy resin containing an alicyclic structure are intermittently stirred at 150° C. for 2 h to obtain an epoxy resin solution; (2) Add defoamer, antioxidant, anti-precipitant and curing agent to the epoxy resin solution in sequence, and stir continuously for 30 min at 100° C. The other steps are the same as those in Example 1. Comparative Example 3 Comparative Example 3 of the present invention provides a fluorescent epoxy film for epoxy CSP lamp beads and a preparation method and application thereof. The specific implementation method is the same as that of Example 1, except that the preparation method of the fluorescent epoxy film for epoxy CSP lamp beads is: (1) an epoxy resin modified with silicone, a trifunctional epoxy compound, and an epoxy resin containing an alicyclic structure are intermittently stirred at 150° C. for 2 h to obtain an epoxy resin solution; (2) Add defoaming agent, antioxidant, anti-precipitation agent and curing agent to the epoxy resin solution in sequence, and stir continuously for 60 minutes at 100° C. The other steps are the same as those in Example 1. Comparative Example 4 Comparative Example 4 of the present invention provides a fluorescent epoxy film for epoxy CSP lamp beads and a preparation method and application thereof. The specific implementation method is the same as that of Example 1, except that the preparation method of the fluorescent epoxy film for epoxy CSP lamp beads is: (1) an epoxy resin modified with silicone, a trifunctional epoxy compound, and an epoxy resin containing an alicyclic structure are intermittently stirred at 150° C. for 2 h to obtain an epoxy resin solution; (2) Add defoamer, antioxidant, anti-precipitant and curing agent to the epoxy resin solution in sequence, and stir continuously for 120 min at 100° C. The other steps are the same as those in Example 1. Performance Testing Methods 1. Hardness test: The fluorescent epoxy adhesive provided in the embodiment and the comparative example was prepared into a sample with a diameter of 25 mm and a thickness of 4 mm. After curing, the hardness of the sample was tested using a Shore D hardness tester. The actual sample picture of the fluorescent epoxy adhesive provided in Example 1 when undergoing hardness test is shown in FIG. Figure 1 The hardness test results of the fluorescent epoxy adhesive provided in the embodiments and comparative examples are shown in Table 1.

[0056] Table 1

[0057] By comparing the hardness test data of Example 1 and Comparative Example 1, it is shown that the hardness of the epoxy material is significantly higher than that of the organic silica gel; by comparing Example 1 and Example 2, it is shown that the phosphor content has little effect on the hardness of the material itself, and the glue skeleton plays a decisive role in the hardness of the material.

[0058] 2. Optical test: A single 0.6*0.3 mm epoxy CSP lamp bead obtained by cutting in the embodiment and the comparative example was welded on a hexagonal substrate, and the luminous flux and color temperature of the CSP were tested using a 10 mA current. The results are shown in Table 2.

[0059] Table 2

[0060] By comparing Example 1 and Comparative Example 1, it can be seen that the difference in materials has a slight effect on the luminous flux and color temperature. By fine-tuning the formula, the photoelectric parameters of the two can be made consistent. By comparing Example 1 and Example 2, it is shown that at a certain color temperature, as the phosphor content increases, the luminous flux can be increased and the color temperature can be reduced. By comparing Example 1 and Example 3, it is shown that for the same phosphor content and test current, the larger the chip size, the lower the brightness and the higher the color temperature.

[0061] 3. Light attenuation test method: (1) The white light CSP lamp beads obtained in the embodiment and the comparative example were welded on a hexagonal substrate, and the initial luminous flux was tested using an integrating sphere; (2) Place the lamp beads in (1) on the lamp bead aging table; (3) Place the aging table in (2) in a double 85 aging box and light it continuously for 168 hours with a current of 10 mA; (4) Calculate the light attenuation using the formula (light attenuation = (luminous flux before aging - luminous flux after aging) / luminous flux before aging * 100%).

[0062] (5) See Table 3 for test results.

[0063] Table 3

[0064] By comparing the light attenuation data, it can be seen that the light attenuation performance of the epoxy resin packaging material of the present inventor is basically consistent with that of the silicone resin material.

[0065] 4. Adhesion test method: The white light CSP lamp beads obtained in Example 1 and Comparative Example 1 are packaged into RGBW lamp beads and placed in a PCT aging box; aged at 121°C for 24 hours, the RGBW lamp beads are taken out, and the interface is observed for abnormalities. The test results are shown in Figure 3 , Figure 4 , Figure 3 and Figure 4 All are RGBW lamp beads, after PCT aging test, Figure 3 The surface is normal. Figure 4 Bubbles appeared on the surface, indicating Figure 3 The bonding force is better.

[0066] 5. Stability test of glue system: (1) Cooling the transparent glue of Implementation 1 and Comparative Example 2 to 30° C. at the same time; (2) Observe whether there is solid resin precipitation in the glue system.

[0067] Test results see Figure 5 , Figure 6 By comparison, it can be seen that the glue of Example 1 is the most stable, and no resin is precipitated. The transparent glue system of Comparative Example 2 is unstable, and there is obvious resin precipitation. It can be seen that by controlling the pre-reaction time of the glue and performing a preliminary reaction between the solid resin and the liquid anhydride curing agent, the stability of the glue can be improved.

Claims

1. A fluorescent epoxy film for epoxy CSP lamp beads, characterized in that: The raw materials for preparing the transparent liquid epoxy glue at least include: transparent liquid epoxy glue and fluorescent powder; the raw materials for preparing the transparent liquid epoxy glue at least include: epoxy resin solution, curing agent, defoaming agent, antioxidant, anti-precipitation agent and catalyst; the epoxy resin solution at least includes silicone-modified epoxy resin, trifunctional epoxy compound and epoxy resin containing alicyclic structure; the melt viscosity of the epoxy resin solution at 150°C is 400-1000Pa.s.

2. The fluorescent epoxy film for epoxy CSP lamp beads according to claim 1, characterized in that: The epoxy resin solution has a melt viscosity of 500-800 Pa.s at 150°C.

3. The fluorescent epoxy film for epoxy CSP lamp beads according to claim 1, characterized in that: The mass ratio of the organosilicon-modified epoxy resin, the trifunctional epoxy compound and the epoxy resin containing an alicyclic structure is 1:(0.5-2):(2-5).

4. The fluorescent epoxy film for epoxy CSP lamp beads according to claim 1, characterized in that: The raw materials for preparing the transparent liquid epoxy adhesive include at least 80-120 parts of epoxy resin solution, 60-90 parts of curing agent, 1-2 parts of defoaming agent, 0.5-2 parts of antioxidant, 1-3 parts of anti-precipitation agent and 0.1-1 parts of catalyst by weight.

5. The fluorescent epoxy film for epoxy CSP lamp beads according to claim 1, characterized in that: The amount of phosphor added to the fluorescent epoxy film is 20-80wt%.

6. The fluorescent epoxy film for epoxy CSP lamp beads according to claim 5, characterized in that: The curing agent is at least one of methyltetrahydrophthalic anhydride, maleic anhydride, tetrahydrophthalic anhydride and pyromellitic dianhydride.

7. The fluorescent epoxy film for epoxy CSP lamp beads according to claim 5, characterized in that: The antioxidant is at least one of antioxidant 1010, antioxidant 168, antioxidant 626, and antioxidant 1135.

8. A method for preparing a fluorescent epoxy film for epoxy CSP lamp beads according to any one of claims 1 to 7, characterized in that: At least the following steps are included: (1) intermittently stirring an organosilicon-modified epoxy resin, a trifunctional epoxy compound, or an epoxy resin containing an alicyclic structure at 140-160° C. for 1-3 hours to obtain an epoxy resin solution; (2) Add defoamer, antioxidant, anti-precipitant and curing agent to the epoxy resin solution in sequence, stir continuously for 60-120 minutes at 90-110°C, cool to 70-80°C and add catalyst, stir manually for 5-15 minutes while keeping warm, stir for 3-8 minutes with a dispersing disk at a speed of 500-800 rpm, and finally control the vacuum degree and stir at a speed of 800-1200 rpm for 3-5 minutes to obtain a transparent liquid epoxy adhesive; (3) Adding fluorescent powder to the transparent liquid epoxy glue, stirring and degassing to obtain the fluorescent epoxy glue; (4) Coat the fluorescent epoxy adhesive on the release film, place it in a 70-90°C forced air drying oven, and bake it for 20-40 minutes to obtain a fluorescent epoxy adhesive film in the B-stage state.

9. An application of the fluorescent epoxy film for epoxy CSP lamp beads according to any one of claims 1 to 7, characterized in that: The invention is applied to the preparation of epoxy CSP lamp beads. The epoxy CSP lamp bead structure comprises a chip, an adhesive layer, a solid crystal plate, and a fluorescent epoxy film. The adhesive layer is attached to the upper surface of the solid crystal plate, the chip is fixed on the upper surface of the adhesive layer, and the fluorescent epoxy film covers the exposed surface of the chip.

10. The use of the fluorescent epoxy film for epoxy CSP lamp beads according to claim 9, characterized in that: The chip has a thickness of 50-150 μm and a chip size of (4-10)×(5-20) mil.

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