Modified ink for improving reflectivity of multi-primary-color LED lighting lamp substrate and preparation method of modified ink

Abstract

The invention discloses modified ink for improving the reflectivity of a substrate of a multi-primary-color LED illuminating lamp and a preparation method of the modified ink, and belongs to the technical field of ink. The modified ink is prepared from the following raw materials: 18 to 26 parts of reflective powder, 35 to 60 parts of organosilicone modified acrylic resin, 10 to 16 parts of biphenyl liquid crystal epoxy resin, 5 to 8 parts of a photoinitiator, 3 to 6 parts of a curing agent, 1.5 to 5 parts of an antioxidant, 0.5 to 1 part of a flatting agent and 30 to 40 parts of a solvent. The composite coated core-shell titanium dioxide is adopted as reflective powder and is matched with the organic silicon modified acrylic resin and the biphenyl liquid crystal epoxy resin to prepare the modified ink, the reflectivity can reach 96% or above under the thickness of 30 microns, the yellowing resistance is excellent, the luminous efficiency utilization rate can be increased, energy consumption is reduced, and the service life of the ink is prolonged. The method can be used for preparing high-quality LED lamps with high brightness and high stability.

Description

Technical Field

[0001] The invention belongs to the technical field of inks, and in particular relates to a modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture and a preparation method thereof. Background Art

[0002] Multi-primary color LEDs (RGBW, RGBY) are considered the core direction of next-generation lighting due to their wide color gamut, high color rendering and dynamic dimming capabilities. However, due to the insufficient reflectivity of traditional packaging substrates (about 60%-90%), the light efficiency of lamps is seriously lost. In this regard, reflective materials such as reflective ink are currently used to build a reflective layer to enhance the focusing effect of LED lamps.

[0003] The luminous efficiency of LED lamps is highly dependent on the reflectivity of reflective materials. Studies have shown that highly reflective fillers such as rutile titanium dioxide can effectively improve reflectivity. In addition, the matrix resin that plays a bonding function is also the key to maintaining high reflective performance. However, traditional reflective inks currently have a large coating thickness and significant scattering losses. At the same time, under subsequent high temperature conditions, the organic resin matrix is ​​prone to yellowing, resulting in light color shift and a significant decrease in reflectivity over time. Carbonyl chromophores are generated during long-term thermal loads (such as LED chip heating and reflow soldering), causing irreversible light decay, which seriously restricts the life of the lamp.

[0004] In view of this, in order to prepare multi-primary color LED lamps with high brightness, high contrast and high stability, it is necessary to conduct further in-depth research on reflective inks. Summary of the invention

[0005] In view of the problems raised in the background technology, the purpose of the present invention is to provide a modified ink for improving the reflectivity of the substrate of a multi-primary color LED lighting fixture and a preparation method thereof. The present invention prepares a modified ink by optimizing the combination of reflective filler and matrix resin, which can effectively improve the reflectivity and yellowing resistance, meet the performance requirements of high-quality LED lamps, and is expected to be applied to high-end fields such as Mini / Micro LED.

[0006] In order to achieve the above object, the present invention specifically adopts the following technical solutions: The present invention provides a modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture, which comprises the following preparation raw materials in parts by weight: Reflective powder 18-26 parts, 35-60 parts of silicone modified acrylic resin, Biphenyl type liquid crystal epoxy resin 10-16 parts, Photoinitiator 5-8 parts, 3-6 parts of curing agent, 1.5-5 parts of antioxidant, 0.5-1 part of leveling agent, 30-40 parts of solvent; The reflective powder includes core-shell titanium dioxide coated with yttrium, erbium and tellurium.

[0007] Furthermore, the reflective powder is composed of core-shell titanium dioxide coated with yttrium, erbium and tellurium and fumed silicon dioxide in a mass ratio of (2-5):1, and the particle size of the reflective powder is 100-200 meshes.

[0008] Furthermore, the preparation method of the yttrium, erbium, and tellurium coated core-shell titanium dioxide is as follows: anatase titanium dioxide nanoparticles are dispersed in deionized water, yttrium nitrate and urea are added and stirred at a constant temperature, and then centrifuged and calcined to obtain Y 2 O 3 Coated TiO 2 ; Continue to disperse the product in a solution of erbium nitrate and polyvinyl pyrrolidone, adjust the pH and stir at a constant temperature, then centrifuge and calcine to obtain Y 2 O 3 , Er 2 O 3 Coated TiO 2 The product is then dispersed in an ethanol solution of tellurium nitrate, the pH is adjusted and the mixture is stirred at a constant temperature, followed by centrifugation and calcination, to finally obtain a core-shell TiO2 composite coated with yttrium, erbium and tellurium. 2 .

[0009] Furthermore, the molar ratio of titanium, yttrium, erbium and tellurium is 100:(8-12):(0.4-0.5):(0.09-0.12).

[0010] Furthermore, the organosilicon-modified acrylic resin is prepared by a hydrosilylation reaction between triethylene glycol dimethacrylate and phenyl hydrogenated silicone resin.

[0011] Furthermore, the biphenyl type liquid crystal epoxy resin is obtained by curing with 3,3',5,5'-tetramethylbiphenyl diglycidyl ether, and the curing agent used is 4,4'-diaminodiphenylmethane.

[0012] Furthermore, the curing agent is an anhydride curing agent, preferably MH-700.

[0013] Furthermore, the photoinitiator is at least one of photoinitiator TPO, photoinitiator ITX or photoinitiator 184; and the antioxidant is 4,6-bis(octylthiomethyl)-o-cresol.

[0014] The present invention also provides a method for preparing the modified ink for improving the reflectivity of the substrate of a multi-primary color LED lighting fixture, comprising: Weigh all raw materials according to the formula, except for the photoinitiator and curing agent, mix the remaining raw materials at high speed and disperse them, then add the photoinitiator and curing agent and mix them evenly with a homogenizer, and then obtain the modified ink after grinding and filtering.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention uses yttrium, erbium and tellurium to sequentially coat anatase titanium dioxide to construct a core-shell structure. The composite coating shell layer can improve dispersibility, enhance interface scattering efficiency, block ultraviolet light penetration and enhance material stability. Through the core-shell structure design, the present invention improves light efficiency utilization and achieves a significant increase in reflectivity.

[0016] 2. The modified ink of the present invention adopts silicone-modified acrylic resin as the base resin and as the main film-forming substance, which provides basic adhesion, enhances heat resistance and flexibility, and at the same time, the benzene-containing silicone ensures the basic yellowing resistance. The present invention also compounded and adopted a biphenyl liquid crystal epoxy resin, which can improve the optical anisotropy of the ink, enhance the reflection uniformity, and construct a dual-curing system with silicone-modified acrylic resin to further improve the crosslinking density and reflectivity.

[0017] 3. According to the reflectivity test, the reflectivity of the modified ink of the present invention can reach 96%-99%, and it has excellent yellowing resistance, which is significantly improved compared with traditional reflective inks. It can be used to prepare high-brightness, high-stability high-quality LED lamps and has good market competitiveness. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the embodiments. If the specific conditions are not specified in the embodiments, they are carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments is not specified, they are all conventional products that can be purchased commercially.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0020] Example 1 A modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture, the preparation method of which is as follows: 1. Anatase titanium dioxide nanoparticles were dispersed in deionized water, yttrium nitrate (yttrium-titanium molar ratio 1:10) and urea were added and stirred at 80°C for 6 h. The product was centrifuged and washed, and then calcined at 520°C for 1 h to obtain Y2 O 3 Coated TiO 2 ; Continue to Y 2 O 3 Coated TiO 2 Dispersed in a solution of erbium nitrate (molar ratio of erbium to yttrium 5:95) and polyvinyl pyrrolidone, the pH was adjusted to 9 and stirred at 70 °C for 4 h. The product was centrifuged and washed, and then calcined at 500 °C for 1.5 h to obtain Y 2 O 3 , Er 2 O 3 Coated TiO 2 ; Then Y 2 O 3 , Er 2 O 3 Coated TiO 2 The product was dispersed in an ethanol aqueous solution of tellurium nitrate (molar ratio of tellurium to erbium 1:5), the pH was adjusted to 6, and the reaction was stirred at 60 °C for 3 h. The product was centrifuged and washed, and then calcined at 360 °C for 1 h to finally obtain a core-shell TiO2 composite coated with yttrium, erbium and tellurium. 2 .

[0021] 2. Take 10 parts by weight of triethylene glycol dimethacrylate and 0.01 parts by weight of platinum catalyst and mix them evenly, then add 7.5 parts by weight of phenyl hydrogenated silicone resin and heat to 90°C, and continue stirring for 3 hours to obtain silicone modified acrylic resin. Take another 10 parts by weight of 3,3',5,5'-tetramethylbiphenyl diglycidyl ether and 1.8 parts by weight of 4,4'-diaminodiphenylmethane and dissolve them in an appropriate amount of dichloromethane, pour the mixed solution into the mold, evacuate, wait for the solvent to evaporate completely, and cure at 100°C for 3 hours, 150°C for 2 hours, and 200°C for 1 hour in turn to obtain biphenyl type liquid crystal epoxy resin.

[0022] 3. Weigh 22 parts of reflective powder by weight (from step 1 core-shell TiO 2 and fumed silica in a mass ratio of 4:1), 48 parts of organosilicon-modified acrylic resin, 14 parts of biphenyl liquid crystal epoxy resin, 7 parts of photoinitiator (composed of photoinitiator TPO and photoinitiator 184 in an equal mass ratio), 5 parts of MH-700, 2.5 parts of 4,6-bis(octylthiomethyl)-o-cresol, 0.8 parts of leveling agent BYK-333, and 36 parts of ethyl acetate. The reflective powder, organosilicon-modified acrylic resin, biphenyl liquid crystal epoxy resin, antioxidant, leveling agent, and solvent are mixed and dispersed at high speed, and then the photoinitiator and curing agent are added and mixed with a homogenizer, ground, and filtered to obtain a modified ink.

[0023] Example 2 A modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture, the preparation method of which is as follows: 1. Anatase titanium dioxide nanoparticles were dispersed in deionized water, yttrium nitrate (yttrium-titanium molar ratio 1:10) and urea were added and stirred at 80°C for 6 h. The product was centrifuged and washed, and then calcined at 520°C for 1 h to obtain Y 2 O 3 Coated TiO 2 ; Continue to Y 2 O 3 Coated TiO 2 Dispersed in a solution of erbium nitrate (erbium to yttrium molar ratio 5:100) and polyvinyl pyrrolidone, the pH was adjusted to 9 and stirred at 70 °C for 4 h. The product was centrifuged and washed, and then calcined at 500 °C for 1.5 h to obtain Y 2 O 3 , Er 2 O 3 Coated TiO 2 ; Then Y 2 O 3 , Er 2 O 3 Coated TiO 2 The product was dispersed in an ethanol aqueous solution of tellurium nitrate (molar ratio of tellurium to erbium 1.2:5), the pH was adjusted to 6, and the reaction was stirred at 60 °C for 3 h. The product was centrifuged and washed, and then calcined at 360 °C for 1 h to finally obtain a core-shell TiO2 composite coated with yttrium, erbium and tellurium. 2 .

[0024] 2. Take 10 parts by weight of triethylene glycol dimethacrylate and 0.01 parts by weight of platinum catalyst and mix them evenly, then add 7.5 parts by weight of phenyl hydrogenated silicone resin and heat to 90°C, and continue stirring for 3 hours to obtain silicone modified acrylic resin. Take another 10 parts by weight of 3,3',5,5'-tetramethylbiphenyl diglycidyl ether and 1.8 parts by weight of 4,4'-diaminodiphenylmethane and dissolve them in an appropriate amount of dichloromethane, pour the mixed solution into the mold, evacuate, wait for the solvent to evaporate completely, and cure at 100°C for 3 hours, 150°C for 2 hours, and 200°C for 1 hour in turn to obtain biphenyl type liquid crystal epoxy resin.

[0025] 3. Weigh 18 parts of reflective powder by weight (from step 1 core-shell TiO 2and fumed silica in a mass ratio of 5:1), 35 parts of organosilicon-modified acrylic resin, 10 parts of biphenyl liquid crystal epoxy resin, 5 parts of photoinitiator (composed of photoinitiator TPO and photoinitiator 184 in equal mass ratio), 3 parts of MH-700, 1.5 parts of 4,6-bis(octylthiomethyl)-o-cresol, 0.5 parts of leveling agent BYK-333, and 30 parts of ethyl acetate. The reflective powder, organosilicon-modified acrylic resin, biphenyl liquid crystal epoxy resin, antioxidant, leveling agent, and solvent are mixed and dispersed at high speed, and then the photoinitiator and curing agent are added and mixed with a homogenizer, ground, and filtered to obtain a modified ink.

[0026] Example 3 A modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture, the preparation method of which is as follows: 1. Anatase titanium dioxide nanoparticles were dispersed in deionized water, yttrium nitrate (yttrium-titanium molar ratio 1:10) and urea were added and stirred at 80°C for 6 h. The product was centrifuged and washed, and then calcined at 520°C for 1 h to obtain Y 2 O 3 Coated TiO 2 ; Continue to Y 2 O 3 Coated TiO 2 Dispersed in a solution of erbium nitrate (erbium to yttrium molar ratio 4:100) and polyvinyl pyrrolidone, the pH was adjusted to 9 and stirred at 70 °C for 4 h. The product was centrifuged and washed, and then calcined at 500 °C for 1.5 h to obtain Y 2 O 3 , Er 2 O 3 Coated TiO 2 ; Then Y 2 O 3 , Er 2 O 3 Coated TiO 2 The product was dispersed in an ethanol aqueous solution of tellurium nitrate (molar ratio of tellurium to erbium 0.9:4), the pH was adjusted to 6, and the reaction was stirred at 60 °C for 3 h. The product was centrifuged and washed, and then calcined at 360 °C for 1 h to finally obtain a core-shell TiO2 composite coated with yttrium, erbium and tellurium. 2 .

[0027] 2. Take 10 parts by weight of triethylene glycol dimethacrylate and 0.01 parts by weight of platinum catalyst and mix them evenly, then add 7.5 parts by weight of phenyl hydrogenated silicone resin and heat to 90°C, and continue stirring for 3 hours to obtain silicone modified acrylic resin. Take another 10 parts by weight of 3,3',5,5'-tetramethylbiphenyl diglycidyl ether and 1.8 parts by weight of 4,4'-diaminodiphenylmethane and dissolve them in an appropriate amount of dichloromethane, pour the mixed solution into the mold, evacuate, wait for the solvent to evaporate completely, and cure at 100°C for 3 hours, 150°C for 2 hours, and 200°C for 1 hour in turn to obtain biphenyl type liquid crystal epoxy resin.

[0028] 3. Weigh 26 parts of reflective powder by weight (from step 1 core-shell TiO 2 and fumed silica in a mass ratio of 4:1), 60 parts of organosilicon-modified acrylic resin, 16 parts of biphenyl liquid crystal epoxy resin, 8 parts of photoinitiator (composed of photoinitiator TPO and photoinitiator 184 in equal mass ratio), 6 parts of MH-700, 4 parts of 4,6-bis(octylthiomethyl)-o-cresol, 1 part of leveling agent BYK-333, and 40 parts of ethyl acetate. The reflective powder, organosilicon-modified acrylic resin, biphenyl liquid crystal epoxy resin, antioxidant, leveling agent, and solvent are mixed and dispersed at high speed, and then the photoinitiator and curing agent are added and mixed with a homogenizer, ground, and filtered to obtain a modified ink.

[0029] Comparative Example 1 Refer to the step parameters of Example 1, except that the intermediate product Y of step 1 is used 2 O 3 , Er 2 O 3 Coated TiO 2 Combined with fumed silica to form reflective powder.

[0030] Comparative Example 2 The step parameters are as in Example 1, except that in step 2, bisphenol A type epoxy resin is used instead of biphenyl type liquid crystal epoxy resin.

[0031] Comparative Example 3 Refer to the step parameters of Example 1, except that in step 3, 22 parts of rutile titanium dioxide are directly used as reflective powder.

[0032] Test example White ink was tested by screen printing (thickness 30 μm) on an aluminum substrate (HQ-R18129) using an 80-mesh steel mesh. 2UV irradiation for 2 min, then transferred to a tunnel oven for high temperature curing at 230°C for 5 min to obtain a reflective coating. The performance of the ink samples prepared above was tested, and the results are shown in Table 1. (Adhesion was tested by the Baige method; reflectivity was tested by a C84-111 reflectivity meter; the high temperature yellowing resistance test condition was placed in a 280°C oven for 10 min; the weathering yellowing resistance test condition was irradiated with a UVA-340 lamp for 168 h, with an irradiance of 0.68 W / m 2 ; The reflow resistance test is to place the coating in a 280℃ oven for 10 min, and the reflectivity decreases by no more than 5% to pass) Table 1 Test results of modified ink

[0033] From the test results in Table 1, it can be seen that the coating samples prepared by the modified inks of Examples 1-3 of the present invention all have high reflectivity and excellent yellowing resistance. The reflectivity is above 96% at a thickness of 30 μm, and the yellowing resistance and reflow resistance tests are passed, showing excellent comprehensive performance. 2 O 3 , Er 2 O 3 Coated TiO 2 As a reflective powder, its reflectivity is significantly reduced, and the yellowing resistance, hardness and whiteness are also reduced to varying degrees. It can be seen that the core-shell titanium dioxide composite-coated with yttrium, erbium and tellurium of the present invention can effectively improve the reflectivity of the coating. In comparative example 2, a modified ink is prepared by using an organosilicon-modified acrylic resin in combination with a bisphenol A epoxy resin. Although the reflectivity is reduced less, the reflectivity is greatly reduced (more than 10%) in the yellowing resistance and reflow resistance tests. It can be seen that the biphenyl liquid crystal epoxy resin prepared by the present invention can effectively improve the yellowing resistance of the coating. Compared with traditional rutile titanium dioxide, the coating sample prepared by the reflective powder of the present invention still has significant advantages in reflectivity and yellowing resistance, which helps to improve the light efficiency utilization rate and reduce energy consumption, and can be used to prepare high-brightness, high-stability high-quality LED lamps.

[0034] Finally, it should be emphasized that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture, characterized in that: The following raw materials are included by weight: Reflective powder 18-26 parts, 35-60 parts of silicone modified acrylic resin, 10-16 parts of biphenyl type liquid crystal epoxy resin, Photoinitiator 5-8 parts, 3-6 parts of curing agent, 1.5-5 parts of antioxidant, 0.5-1 part of leveling agent, 30-40 parts of solvent; The reflective powder includes core-shell titanium dioxide coated with yttrium, erbium and tellurium.

2. The modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture according to claim 1, characterized in that: The reflective powder is composed of core-shell titanium dioxide coated with yttrium, erbium and tellurium and fumed silicon dioxide in a mass ratio of (2-5):

1.

3. The modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture according to claim 1, characterized in that: The preparation method of the yttrium, erbium and tellurium coated core-shell titanium dioxide is as follows: taking anatase titanium dioxide nanoparticles and dispersing them in deionized water, adding yttrium nitrate and urea and stirring at a constant temperature, then centrifuging and calcining to obtain Y2O3-coated TiO2; continuing to disperse the product in a solution of erbium nitrate and polyvinyl pyrrolidone, adjusting the pH and stirring at a constant temperature, then centrifuging and calcining to obtain Y2O3 and Er2O3-coated TiO2; then dispersing the product in an ethanol aqueous solution of tellurium nitrate, adjusting the pH and stirring at a constant temperature, then centrifuging and calcining to finally obtain yttrium, erbium and tellurium composite-coated core-shell TiO2.

4. The modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture according to claim 3, characterized in that: The molar ratio of titanium, yttrium, erbium and tellurium is 100:(8-12):(0.4-0.5):(0.09-0.12).

5. The modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture according to claim 1, characterized in that: The organosilicon-modified acrylic resin is prepared by the hydrosilylation reaction of triethylene glycol dimethacrylate and phenyl hydrogen-containing silicone resin.

6. The modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture according to claim 1, characterized in that: The biphenyl type liquid crystal epoxy resin is prepared by curing with 3,3',5,5'-tetramethylbiphenyl diglycidyl ether, and the curing agent used is 4,4'-diaminodiphenylmethane.

7. The modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture according to claim 1, characterized in that: The curing agent is an acid anhydride curing agent.

8. The modified ink for improving the reflectivity of a substrate of a multi-primary color LED lighting fixture according to claim 1, characterized in that: The photoinitiator is at least one of photoinitiator TPO, photoinitiator ITX or photoinitiator 184; the antioxidant is 4,6-bis(octylthiomethyl)-o-cresol.

9. The method for preparing the modified ink for improving the reflectivity of the substrate of a multi-primary color LED lighting fixture according to any one of claims 1 to 8, characterized in that: include: Weigh all raw materials according to the formula, except for the photoinitiator and curing agent, mix the remaining raw materials at high speed and disperse them, then add the photoinitiator and curing agent and mix them evenly with a homogenizer, and then obtain the modified ink after grinding and filtering.

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