A phosphor composition for high color rendering index LED and high stability LED device

Abstract

The present invention belongs to the technical field of phosphor materials and LED devices, and specifically relates to a phosphor composition for high color rendering index LED and a high stability LED device. The phosphor composition is composed of the following components in the range of luminous peak wavelength: 0.5-0.8 parts of yellow-green phosphor a of 520±2nm; 0.2-0.4 parts of yellow-green phosphor b of 530±2nm; 0.1-0.3 parts of green phosphor of 490±1nm; 0.03-0.1 parts of red phosphor of 660±2nm; 0.5-0.8 parts of light green phosphor a of 700±10nm; 0.2-0.5 parts of light green phosphor b of 760±10nm; 0.1-0.2 parts of light green phosphor c of 800±10nm. The phosphor composition and LED device of the present invention have significantly improved color rendering index and color rendering stability.

Description

Technical Field

[0001] The invention belongs to the technical field of phosphor materials and LED devices, and in particular relates to a phosphor composition for high color rendering index LED and a high stability LED device. Background Art

[0002] Light Emitting Diode (LED) has the advantages of high efficiency, energy saving, environmental protection, long life, small size and easy maintenance. It has become the mainstream of advertising decoration, urban lighting projects and lighting sources, and its application fields are becoming increasingly wide.

[0003] The color rendering index is a measure of the color rendering of a light source, expressed as the degree of conformity between the color of an object under the measured light source and the color of an object under the reference standard light source. The general color rendering index is the average value of the color rendering index of the light source for the 1st to 8th standard color samples specified by the International Commission on Illumination, commonly known as the color rendering index, and the symbol is Ra. The color rendering index is an important method for evaluating the color rendering of a light source and an important parameter for measuring the color characteristics of artificial light sources. The higher the color rendering index, the better the color rendering of the light source and the stronger the color reproduction ability of the object. General color rendering index: The larger the Ra, the better the color rendering performance; conversely, the worse the color rendering. The color rendering index of sunlight is defined as 100.

[0004] Although the "color rendering index" cannot represent the whole of a lamp. However, a "high color rendering index" can largely determine the effect of lighting - high color reproduction. Ra usually refers to the average value of the light source's level of reproduction of eight natural colors, R1-R8, and R9-R15 is not included. However, from a professional perspective, when evaluating the color rendering index of a light source, the parameters of R9 (red reproduction) and R15 (performance of Asian skin color) should be considered.

[0005] Patents CN 115948162 B and CN 116083082 B both disclose a high color rendering phosphor composition. The LED package device prepared by using a phosphor composition with a specific luminous color has the advantage of a high color rendering index. In our previous patent CN 117568035 B, by adding a high-wavelength phosphor composition, the full spectrum wavelength of the LED lamp bead light source is made more comprehensive, and the peak value of the emission wave is stimulated, thereby improving the color rendering ability at this stage. However, the color rendering index of the above-mentioned phosphor composition still has room for further improvement.

[0006] At present, high-performance LED devices are generally obtained by mixing phosphors and silicone LED potting glue and then baking and curing them for LED chip packaging. Due to the large difference in surface tension between phosphors and silicone LED potting glue, phosphors aggregate and settle during the mixing and baking curing process. At the same time, the binding force between phosphors and potting glue is weak, resulting in degradation of phosphor performance, reduced transparency of phosphor glue, and ultimately reduced color rendering effect. Therefore, how to improve the color rendering stability of LED devices is a technical problem that technicians in this field need to further solve. Summary of the invention

[0007] In view of the shortcomings and deficiencies of the above prior art, the primary purpose of the present invention is to provide a phosphor composition for LED with a high color rendering index.

[0008] Another object of the present invention is to provide an LED device with high color rendering index and high stability.

[0009] Another object of the present invention is to provide a method for preparing the above-mentioned LED device with high color rendering index and high stability.

[0010] The purpose of the present invention is achieved through the following technical solutions:

[0011] A phosphor composition for LED with high color rendering index, comprising the following components in parts by weight:

[0012] 0.5 to 0.8 parts of yellow-green phosphor a with a peak emission wavelength of 520±2nm;

[0013] 0.2 to 0.4 parts of yellow-green phosphor b with a peak emission wavelength range of 530±2nm;

[0014] 0.1 to 0.3 parts of green phosphor with a peak emission wavelength range of 490 ± 1nm;

[0015] 0.03 to 0.1 parts of red phosphor with a peak emission wavelength range of 660 ± 2nm;

[0016] 0.5 to 0.8 parts of light green phosphor a with a peak emission wavelength range of 700 ± 10 nm;

[0017] 0.2 to 0.5 parts of light green phosphor b with a peak emission wavelength range of 760±10nm;

[0018] 0.1 to 0.2 parts of light green phosphor c with a peak emission wavelength range of 800±10nm.

[0019] It should be noted that the above-mentioned light green phosphor a, light green phosphor b and light green phosphor c are names given in the industry based on the colors of the phosphors, and are not descriptions of their peak luminous colors.

[0020] Furthermore, the particle size D50 value of the yellow-green phosphor a is 16μm~20μm; the particle size D50 value of the yellow-green phosphor b is 18μm~22μm; the particle size D50 value of the green phosphor is 11μm~15μm; the particle size D50 value of the red phosphor is in the range of 13μm~17μm; the particle size D50 value of the light green phosphor a is in the range of 19μm~23μm; the particle size D50 value of the light green phosphor b is in the range of 20μm~24μm; the particle size D50 value of the light green phosphor c is 16μm~20μm.

[0021] A high color rendering index and high stability LED device comprises an LED chip with a luminous peak wavelength range of 430-435nm, 450-452nm and 460-470nm, and a phosphor glue for encapsulating the LED chip; the phosphor glue comprises an LED potting glue and a phosphor composition dispersed therein.

[0022] Furthermore, the color rendering index of the high color rendering index and high stability LED device is Ra≥99, R9≥99, and R15≥99.

[0023] A method for preparing a high color rendering index and high stability LED device comprises the following preparation steps:

[0024] (1) Surface modification of phosphor composition:

[0025] The phosphor composition and the alkylbenzene sulfonate dispersant are added to an ethanol aqueous solution and stirred to disperse uniformly, then the temperature is raised to 70-85° C., an acid catalyst and a silicate compound are added dropwise and stirred to react for 1-4 hours, and then a vinyl silane coupling agent is added and stirred to react for 0.5-2 hours, and the product is filtered, washed, and dried to obtain a vinyl surface-modified phosphor composition;

[0026] (2) Preparation of silicone LED potting glue:

[0027] The phenyl vinyl silicone oil, hydrogen-containing silicone oil, inhibitor and catalyst are stirred and mixed to obtain an organic silicone LED potting adhesive;

[0028] (3) Preparation of phosphor glue:

[0029] The vinyl surface-modified phosphor composition of step (1) and the organosilicon LED potting glue of step (2) are mixed and stirred evenly, and allowed to stand or vacuum degas, to obtain phosphor glue;

[0030] (4) LED chip packaging and curing:

[0031] The LED chip is encapsulated by injection molding using the fluorescent powder glue of step (3), and then heated, baked and cured to obtain an LED device with a high color rendering index and high stability.

[0032] Furthermore, the alkylbenzene sulfonate dispersant in step (1) is sodium dodecylbenzene sulfonate, and the amount of the alkylbenzene sulfonate dispersant added is 1% to 4% by mass of the phosphor composition.

[0033] Furthermore, the ethanol aqueous solution in step (1) refers to an ethanol aqueous solution with an ethanol mass fraction of 70% to 90%.

[0034] Furthermore, the acidic catalyst in step (1) is hydrochloric acid.

[0035] Furthermore, the silicate compound in step (1) is ethyl orthosilicate or isopropyl orthosilicate, and the amount of the silicate compound added is 4% to 20% of the mass of the phosphor composition.

[0036] Furthermore, the vinyl silane coupling agent in step (1) is vinyl triethoxy silane or vinyl trimethoxy silane, and the amount of the vinyl silane coupling agent added is 2% to 10% of the mass of the phosphor composition.

[0037] Furthermore, the phenyl vinyl silicone oil in step (2) is a commonly used organic silicon encapsulation adhesive raw material for LEDs in the art, which has the advantages of high refractive index and high temperature resistance, corrosion resistance, and resistance to ultraviolet radiation. The phenyl content of the phenyl vinyl silicone oil is 5% to 30% (mass percentage), and the vinyl content is 2% to 10% (mass percentage); the viscosity of the phenyl vinyl silicone oil is 1000 to 4000 mPa.s (25°C).

[0038] Furthermore, the hydrogen-containing silicone oil in step (2) is a commonly used organic silicon encapsulation adhesive raw material for LEDs in the art. The hydrogen content of the hydrogen-containing silicone oil used in the present invention is 0.1% to 0.6% (mass percentage of active H connected to Si); the viscosity of the hydrogen-containing silicone oil is 100 to 2000 mPa.s (25° C.); the mass of the hydrogen-containing silicone oil is 10% to 40% of the mass of the phenyl vinyl silicone oil.

[0039] Furthermore, the inhibitor in step (2) is an acetylenic alcohol inhibitor, and the mass of the inhibitor is 0.02% to 0.2% of the mass of the phenyl vinyl silicone oil; the catalyst is a Karstedt catalyst (platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane), and the mass of the catalyst is 0.005% to 0.02% of the mass of the phenyl vinyl silicone oil.

[0040] Furthermore, the weight percentage of the vinyl surface-modified phosphor composition in the phosphor glue in step (3) is 5% to 20%.

[0041] Furthermore, the heating and baking curing in step (4) refers to first baking at 70-90° C. for 1-2 hours, and then heating to 150-160° C. for 4-5 hours.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] (1) The present invention can further improve the color rendering index of the LED device by further optimizing the combination of phosphors with different luminous peak wavelengths and adding high-wavelength phosphor compositions, especially by using a high-wavelength combination with luminous peak wavelengths in the range of 700±10nm, 760±10nm and 800±10nm.

[0044] (2) The present invention further uses LED chips with peak emission wavelengths in the range of 430-435 nm, 450-452 nm and 460-470 nm as the excitation light source of the phosphor composition, which can further improve the color rendering index of the LED device.

[0045] (3) The LED device of the present invention has good dispersion compatibility with the silicone LED potting glue during the mixing process by performing vinyl surface modification on the phosphor composition. In addition, it can undergo chemical cross-linking reaction with hydrogen-containing silicone oil during the injection packaging curing process, thereby significantly improving the bonding effect between the phosphor composition and the potting glue. On the one hand, the stability of the phosphor is improved and the degradation of the phosphor performance is reduced. On the other hand, the LED potting glue is reinforced, its weather resistance is improved, and yellowing is reduced. On the other hand, the mixing compatibility and transparency of the phosphor glue are improved, and finally the color stability of the LED device is improved.

[0046] (4) In the process of surface modification of the phosphor composition of the present invention, an alkylbenzene sulfonate dispersant is used and SiO2 coating modification and vinyl silane coupling agent surface modification are carried out under acidic catalyst conditions. Compared with the conditions without dispersant and alkaline catalyst conditions, the surface modification effect can be significantly improved and the influence on the composition and performance of the phosphor can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 is the excitation spectrum diagram of the LED device obtained in Example 1;

[0048] Figure 2 and Figure 3 They are the excitation spectra of the LED devices obtained in Comparative Examples 1 and 2 respectively. DETAILED DESCRIPTION

[0049] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0050] Example 1

[0051] A phosphor composition for LED with high color rendering index, comprising the following components in parts by weight:

[0052] Yellow-green phosphor a 0.6 parts (cerium-doped gallate, Yantai Hild Materials Technology Co., Ltd., LED phosphor SDG520, luminous peak wavelength 520 ± 2nm, density 4.5g / cm 3 , D50 particle size 18.0±2.0μm);

[0053] Yellow-green phosphor b 0.3 parts (cerium-doped gallate, Yantai Hild Materials Technology Co., Ltd., LED phosphor SDG530, peak wavelength of 530±2nm, density 4.0g / cm 3 , D50 particle size 20.0±2.0μm);

[0054] 0.2 parts of green phosphor (Europium-doped oxynitride, Yantai Hild Materials Technology Co., Ltd., LED phosphor SDG490, peak wavelength of luminescence 490±1nm, density 4.0g / cm 3 , D50 particle size 13.0±2.0μm);

[0055] 0.06 parts of red phosphor (nitride, Yantai Hild Materials Technology Co., Ltd., LED phosphor SSDR660, peak wavelength of 660±2nm, density 3.2g / cm 3 , D50 particle size 15.0±2.0μm);

[0056] Light green phosphor a 0.7 parts (rare earth aluminate, Yantai Hild Materials Technology Co., Ltd., LED phosphor SDIR700, luminous peak wavelength 700 ± 10nm, density 3.9g / cm 3 , D50 particle size 21.0±2.0μm);

[0057] Light green phosphor b 0.3 parts (rare earth aluminate, Yantai Hild Materials Technology Co., Ltd., LED phosphor SDIR760, luminous peak wavelength 760 ± 10nm, density 3.9g / cm 3 , D50 particle size 22.0±2.0μm);

[0058] Light green phosphor c 0.15 parts (rare earth aluminate, Yantai Hild Materials Technology Co., Ltd., LED phosphor SDIR800, luminous peak wavelength 800 ± 10nm, density 3.9g / cm 3 , D50 particle size 18.0±2.0μm).

[0059] Weigh each phosphor according to mass and mix them evenly to obtain a phosphor composition for LED with a high color rendering index.

[0060] A method for preparing a high color rendering index and high stability LED device comprises the following preparation steps:

[0061] (1) Surface modification of phosphor composition:

[0062] The above-mentioned phosphor composition and 3% (relative to the mass of the phosphor composition) alkylbenzene sulfonate dispersant are added to 82wt.% ethanol aqueous solution and stirred to disperse evenly, then the temperature is raised to 80±2°C, hydrochloric acid catalyst and 12% (relative to the mass of the phosphor composition) ethyl orthosilicate are added dropwise and stirred to react for 2h, and then 5% (relative to the mass of the phosphor composition) vinyltriethoxysilane is added and stirred to react for 1h. The product is filtered, washed with deionized water and ethanol in turn, and vacuum dried to obtain a vinyl surface-modified phosphor composition.

[0063] (2) Preparation of silicone LED potting glue:

[0064] Measured by mass, 100 parts of phenyl vinyl silicone oil (phenyl content of 22.5%, vinyl content of 4.2%, viscosity of 1760mPa.s at 25°C), 25 parts of hydrogen-containing silicone oil (hydrogen content of 0.38%, viscosity of 620mPa.s at 25°C), 0.1 parts of ethynyl cyclohexanol and 0.012 parts of Karstedt catalyst were stirred and mixed uniformly to obtain a silicone LED potting compound.

[0065] (3) Preparation of phosphor glue:

[0066] The vinyl surface-modified phosphor composition of step (1) and the organosilicon LED potting glue of step (2) were stirred and mixed evenly at a mass ratio of 10:90, and allowed to stand at room temperature for 12 hours to degas, thereby obtaining phosphor glue.

[0067] (4) LED chip packaging and curing:

[0068] The fluorescent powder glue of step (3) is used to inject glue and package the LED chip (including three blue light LED excitation chips with emission peak wavelengths of 430-435nm, 450-452nm and 465-470nm), put it into an 80°C oven and bake it for 1h, then heat it to 150°C and bake it for 4h to obtain a high color rendering index and high stability LED device.

[0069] The transmittance of the fluorescent powder glue obtained in this embodiment after curing was measured to be 92.9%, and the refractive index was 1.57; the transmittance after 1000h of ultraviolet (380nm) aging treatment was 91.5%; the transmittance after 1000h of thermal oxygen (150°C air) aging treatment was 90.4%.

[0070] The excitation spectrum of the LED device obtained in this embodiment is shown in FIG. Figure 1 As shown. Figure 1 As can be seen from the results, the color rendering index of the LED device obtained in this embodiment is Ra=99.2, R9=99, R15=99; and the color temperature Tc=3905K. After 1000h of ultraviolet (380nm) aging treatment, the color rendering index is Ra=98.7, R9=97, R15=98; and the color temperature Tc=3890K; after 1000h of thermal oxygen (150℃ air) aging treatment, the color rendering index is Ra=98.4, R9=97, R15=97; and the color temperature Tc=3876K.

[0071] It can be seen from the above results that the phosphor composition and LED device obtained by the present invention have a higher color rendering index and excellent aging stability.

[0072] Example 2

[0073] A phosphor composition for LED with high color rendering index, comprising the following components in parts by weight:

[0074] Yellow-green phosphor a 0.5 parts (cerium-doped gallate, luminescence peak wavelength 520±2nm, density 4.5g / cm 3 , D50 particle size 18.0±2.0μm);

[0075] Yellow-green phosphor b 0.2 parts (cerium-doped gallate, luminescence peak wavelength 530±2nm, density 4.0g / cm 3 , D50 particle size 20.0±2.0μm);

[0076] 0.3 parts of green phosphor (Europium doped oxynitride, luminescence peak wavelength 490±1nm, density 4.0g / cm 3 , D50 particle size 13.0±2.0μm);

[0077] 0.1 part of red phosphor (nitride, peak wavelength of luminescence is 660±2nm, density is 3.2g / cm 3 , D50 particle size 15.0±2.0μm);

[0078] 0.5 parts of light green phosphor a (rare earth aluminate, luminescence peak wavelength is 700±10nm, density is 3.9g / cm 3 , D50 particle size 21.0±2.0μm);

[0079] Light green phosphor b 0.2 parts (rare earth aluminate, luminescence peak wavelength 760±10nm, density 3.9g / cm 3 , D50 particle size 22.0±2.0μm);

[0080] Light green phosphor c 0.1 parts (rare earth aluminate, luminescence peak wavelength 800±10nm, density 3.9g / cm 3 , D50 particle size 18.0±2.0μm).

[0081] The preparation method of the phosphor composition for high color rendering index LED and the preparation method of the high color rendering index and high stability LED device are the same as those in Example 1.

[0082] The transmittance of the fluorescent powder glue obtained in this embodiment after curing was measured to be 92.5%, and the refractive index was 1.57; the transmittance after 1000h of ultraviolet (380nm) aging treatment was 91.4%; the transmittance after 1000h of thermal oxygen (150°C air) aging treatment was 90.4%.

[0083] The color rendering index of the LED device obtained in this embodiment is Ra=99.3, R9=99, R15=99; color temperature Tc=4120K. After 1000h of ultraviolet (380nm) aging treatment, the color rendering index is Ra=98.6, R9=97, R15=98; color temperature Tc=4068K; after 1000h of thermal oxygen (150℃ air) aging treatment, the color rendering index is Ra=98.3, R9=97, R15=97; color temperature Tc=4037K.

[0084] It can be seen from the above results that the phosphor composition and LED device obtained by the present invention have a higher color rendering index and excellent aging stability.

[0085] Example 3

[0086] A phosphor composition for LED with high color rendering index, comprising the following components in parts by weight:

[0087] Yellow-green phosphor a 0.8 parts (cerium-doped gallate, luminescence peak wavelength 520±2nm, density 4.5g / cm 3 , D50 particle size 18.0±2.0μm);

[0088] Yellow-green phosphor b 0.4 parts (cerium-doped gallate, luminescence peak wavelength 530±2nm, density 4.0g / cm 3 , D50 particle size 20.0±2.0μm);

[0089] 0.1 parts of green phosphor (Europium doped oxynitride, luminescence peak wavelength 490±1nm, density 4.0g / cm 3 , D50 particle size 13.0±2.0μm);

[0090] 0.03 parts of red phosphor (nitride, luminescence peak wavelength is 660±2nm, density is 3.2g / cm3 , D50 particle size 15.0±2.0μm);

[0091] Light green phosphor a 0.8 parts (rare earth aluminate, luminescence peak wavelength 700 ± 10nm, density 3.9g / cm 3 , D50 particle size 21.0±2.0μm);

[0092] Light green phosphor b 0.5 parts (rare earth aluminate, luminescence peak wavelength 760 ± 10nm, density 3.9g / cm 3 , D50 particle size 22.0±2.0μm);

[0093] Light green phosphor c 0.2 parts (rare earth aluminate, luminescence peak wavelength 800±10nm, density 3.9g / cm 3 , D50 particle size 18.0±2.0μm).

[0094] The preparation method of the phosphor composition for high color rendering index LED and the preparation method of the high color rendering index and high stability LED device are the same as those in Example 1.

[0095] The transmittance of the fluorescent powder glue obtained in this embodiment after curing was measured to be 92.6%, and the refractive index was 1.57; the transmittance after 1000h of ultraviolet (380nm) aging treatment was 91.5%; the transmittance after 1000h of thermal oxygen (150°C air) aging treatment was 90.6%.

[0096] The color rendering index of the LED device obtained in this embodiment is Ra=99.2, R9=99, R15=99; color temperature Tc=3889K. After 1000h of ultraviolet (380nm) aging treatment, the color rendering index is Ra=98.5, R9=97, R15=98; color temperature Tc=3812K; after 1000h of thermal oxygen (150℃ air) aging treatment, the color rendering index is Ra=98.1, R9=97, R15=97; color temperature Tc=3801K.

[0097] It can be seen from the above results that the phosphor composition and LED device obtained by the present invention have a higher color rendering index and excellent aging stability.

[0098] Example 4

[0099] A phosphor composition for LED with high color rendering index, whose components are the same as those in Example 1.

[0100] A method for preparing a high color rendering index and high stability LED device comprises the following preparation steps:

[0101] (1) Surface modification of phosphor composition:

[0102] The above phosphor composition and 1% (relative to the mass of the phosphor composition) alkylbenzene sulfonate dispersant are added into 90wt.% ethanol aqueous solution and stirred to disperse evenly, then the temperature is raised to 80±2°C, hydrochloric acid catalyst and 20% (relative to the mass of the phosphor composition) ethyl orthosilicate are added dropwise and stirred to react for 2h, then 2% (relative to the mass of the phosphor composition) vinyltrimethoxysilane is added and stirred to react for 1h, the product is filtered, washed with deionized water and ethanol in turn, and vacuum dried to obtain a vinyl surface-modified phosphor composition.

[0103] (2) Preparation of silicone LED potting glue:

[0104] Measured by mass, 100 parts of phenyl vinyl silicone oil (phenyl content is 28.0%, vinyl content is 3.6%, viscosity at 25°C is 1520mPa.s), 10 parts of hydrogen-containing silicone oil (hydrogen content is 0.60%, viscosity at 25°C is 150mPa.s), 0.2 parts of ethynyl cyclohexanol and 0.02 parts of Karstedt catalyst are stirred and mixed to obtain a silicone LED potting adhesive.

[0105] (3) Preparation of phosphor glue:

[0106] The vinyl surface-modified phosphor composition of step (1) and the organosilicon LED potting glue of step (2) were stirred and mixed evenly at a mass ratio of 10:90, and allowed to stand at room temperature for 12 hours to degas, thereby obtaining phosphor glue.

[0107] (4) LED chip packaging and curing:

[0108] The fluorescent powder glue of step (3) is used to inject glue and package the LED chip (including three blue light LED excitation chips with emission peak wavelengths of 430-435nm, 450-452nm and 465-470nm), put it into an 80°C oven and bake it for 1h, then heat it to 150°C and bake it for 4h to obtain a high color rendering index and high stability LED device.

[0109] The transmittance of the fluorescent powder glue obtained in this embodiment after curing was measured to be 93.2%, and the refractive index was 1.58; the transmittance after 1000h of ultraviolet (380nm) aging treatment was 92.1%; the transmittance after 1000h of thermal oxygen (150°C air) aging treatment was 91.5%.

[0110] The color rendering index of the LED device obtained in this embodiment is Ra=99.1, R9=99, R15=99; color temperature Tc=3952K. After 1000h of ultraviolet (380nm) aging treatment, the color rendering index is Ra=98.6, R9=98, R15=98; color temperature Tc=3930K; after 1000h of thermal oxygen (150℃ air) aging treatment, the color rendering index is Ra=98.2, R9=97, R15=98; color temperature Tc=3906K.

[0111] It can be seen from the above results that the phosphor composition and LED device obtained by the present invention have a higher color rendering index and excellent aging stability.

[0112] Example 5

[0113] A phosphor composition for LED with high color rendering index, whose components are the same as those in Example 1.

[0114] A method for preparing a high color rendering index and high stability LED device comprises the following preparation steps:

[0115] (1) Surface modification of phosphor composition:

[0116] The above phosphor composition and 4% (relative to the mass of the phosphor composition) alkylbenzene sulfonate dispersant are added into 70wt.% ethanol aqueous solution and stirred to disperse evenly, then the temperature is raised to 80±2°C, hydrochloric acid catalyst and 4% (relative to the mass of the phosphor composition) isopropyl orthosilicate are added dropwise and stirred to react for 2h, then 10% (relative to the mass of the phosphor composition) vinyltriethoxysilane is added and stirred to react for 1h, the product is filtered, washed with deionized water and ethanol in turn, and vacuum dried to obtain a vinyl surface-modified phosphor composition.

[0117] (2) Preparation of silicone LED potting glue:

[0118] Measured by mass, 100 parts of phenyl vinyl silicone oil (phenyl content of 15.6%, vinyl content of 7.5%, viscosity of 25°C of 2200mPa.s), 40 parts of hydrogen-containing silicone oil (hydrogen content of 0.18%, viscosity of 1250mPa.s at 25°C), 0.02 parts of ethynyl cyclohexanol and 0.005 parts of Karstedt catalyst were stirred and mixed to obtain a silicone LED potting compound.

[0119] (3) Preparation of phosphor glue:

[0120] The vinyl surface-modified phosphor composition of step (1) and the organosilicon LED potting glue of step (2) were stirred and mixed evenly at a mass ratio of 10:90, and allowed to stand at room temperature for 12 hours to degas, thereby obtaining phosphor glue.

[0121] (4) LED chip packaging and curing:

[0122] The fluorescent powder glue of step (3) is used to inject glue and package the LED chip (including three blue light LED excitation chips with peak emission wavelengths of 430-435nm, 450-452nm and 460-465nm), put it into an 80°C oven and bake it for 1h, then heat it to 150°C and bake it for 4h to obtain a high color rendering index and high stability LED device.

[0123] The transmittance of the fluorescent powder glue obtained in this embodiment after curing was measured to be 92.2%, and the refractive index was 1.56; the transmittance after 1000h of ultraviolet (380nm) aging treatment was 91.0%; the transmittance after 1000h of thermal oxygen (150°C air) aging treatment was 90.1%.

[0124] The color rendering index of the LED device obtained in this embodiment is Ra=99.4, R9=99, R15=99; color temperature Tc=3895K. After 1000h of ultraviolet (380nm) aging treatment, the color rendering index is Ra=98.8, R9=97, R15=98; color temperature Tc=3887K; after 1000h of thermal oxygen (150℃ air) aging treatment, the color rendering index is Ra=98.1, R9=97, R15=96; color temperature Tc=3853K.

[0125] It can be seen from the above results that the phosphor composition and LED device obtained by the present invention have a higher color rendering index and excellent aging stability.

[0126] Comparative Example 1

[0127] A phosphor composition of this comparative example uses 0.45 parts of a phosphor composition having a peak luminescence wavelength of 780±10nm and a density of 3.9g / cm 3 , the rare earth aluminate light green phosphor with a D50 particle size of 20.0±2.0 μm replaces the light green phosphors b and c in Example 1, and the rest are the same.

[0128] The excitation spectrum of the LED device obtained in this comparative example is as follows Figure 2 As shown. Figure 2 The results show that the color rendering index of the LED device obtained in this comparative example is Ra=98.4, R9=92, R15=98; and the color temperature Tc=3980K.

[0129] It can be seen from the above results that the phosphor of the present invention further adopts a combination of luminescent peak wavelengths of 760±10nm and 800±10nm, which can further improve the color rendering index of the LED device compared with the phosphor combination with a luminescent peak wavelength of 780±10nm.

[0130] Comparative Example 2

[0131] An LED device in this comparative example uses two blue light LED excitation chips with peak emission wavelengths of 430-435nm and 465-470nm to replace the three blue light LED excitation chips with peak emission wavelengths of 430-435nm, 450-452nm and 465-470nm in Example 1, and the rest are the same.

[0132] The excitation spectrum of the LED device obtained in this comparative example is as follows Figure 3 As shown. Figure 3 The results show that the color rendering index of the LED device obtained in this comparative example is Ra=96.4, R9=90, R15=96; and the color temperature Tc=3987K.

[0133] From the above results, it can be seen that the LED device of the present invention further adopts three blue light LED excitation chips with peak emission wavelengths of 430-435nm, 450-452nm and 465-470nm, which can further significantly improve the color rendering index of the LED device compared to the lack of two blue light LED excitation chips with 450-452nm.

[0134] Comparative Example 3

[0135] In the LED device of this comparative example, the phosphor composition is not surface-modified, and the rest is the same as in Example 1.

[0136] The transmittance of the fluorescent powder glue obtained in this comparative example after curing was 88.2%, and the refractive index was 1.55; the transmittance after 1000h of ultraviolet (380nm) aging treatment was 80.1%; the transmittance after 1000h of thermal oxygen (150℃ air) aging treatment was 78.6%.

[0137] The color rendering index of the LED device obtained in this comparative example is Ra=99.1, R9=99, R15=99; color temperature Tc=3893K. After 1000h of ultraviolet (380nm) aging treatment, the color rendering index is Ra=96.2, R9=95, R15=95; color temperature Tc=3626K; after 1000h of thermal oxygen (150℃ air) aging treatment, the color rendering index is Ra=95.7, R9=94, R15=95; color temperature Tc=3550K.

[0138] By comparing the results of this comparative example with Example 1, it can be seen that the present invention can significantly improve the transparency and anti-aging performance of the LED encapsulation adhesive by SiO2 coating modification and vinyl silane coupling agent surface modification of the phosphor composition, and the color stability of the LED device is also significantly improved.

[0139] Comparative Example 4

[0140] In the LED device of this comparative example, methyltriethoxysilane without vinyl group is used to replace vinyltriethoxysilane to modify the surface of the phosphor composition, and the rest is the same as that of Example 1.

[0141] The transmittance of the fluorescent powder glue obtained in this comparative example after curing was measured to be 90.5%, and the refractive index was 1.56; the transmittance after 1000h of ultraviolet (380nm) aging treatment was 83.4%; the transmittance after 1000h of thermal oxygen (150℃ air) aging treatment was 82.7%.

[0142] The color rendering index of the LED device obtained in this comparative example is Ra=99.3, R9=99, R15=99; and the color temperature Tc=3922K. After 1000h of ultraviolet (380nm) aging treatment, the color rendering index is Ra=97.0, R9=96, R15=96; and the color temperature Tc=3854K; after 1000h of thermal oxygen (150℃ air) aging treatment, the color rendering index is Ra=96.9, R9=95, R15=96; and the color temperature Tc=3729K.

[0143] By comparing the results of this comparative example with Example 1, it can be seen that the present invention uses a vinyl silane coupling agent that can undergo a chemical cross-linking reaction with the silicone LED potting adhesive to modify the surface of the phosphor composition, which can significantly improve the transparency and anti-aging performance of the LED encapsulation adhesive and significantly improve the color stability of the LED device.

[0144] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A phosphor composition for LED with high color rendering index, characterized in that: It is composed of the following components in parts by mass: 0.5~0.8 parts of yellow-green phosphor with a peak emission wavelength of 520±2 nm; 0.2~0.4 parts of yellow-green phosphor b with a peak emission wavelength range of 530±2 nm; 0.1~0.3 parts of green phosphor with a peak emission wavelength range of 490±1 nm; 0.03~0.1 parts of red phosphor with a peak emission wavelength range of 660±2 nm; 0.5-0.8 parts of light green phosphor a with a peak emission wavelength of 700±10 nm; 0.2~0.5 parts of light green phosphor b with a peak emission wavelength range of 760±10 nm; 0.1~0.2 parts of light green phosphor c with a peak emission wavelength range of 800±10 nm; The yellow-green phosphor a is the cerium-doped gallate LED phosphor SDG520 produced by Yantai Shield Material Technology Co., Ltd., with a density of 4.5 g / cm 3 , D50 particle size 18.0±2.0μm; The yellow-green phosphor b is the cerium-doped gallate LED phosphor SDG530 produced by Yantai Shield Material Technology Co., Ltd., with a density of 4.0 g / cm 3 , D50 particle size 20.0±2.0μm; The green phosphor is the europium-doped nitrogen oxide LED phosphor SDG490 produced by Yantai Shield Material Technology Co., Ltd., with a density of 4.0 g / cm 3 , D50 particle size 13.0±2.0μm; The red phosphor is the nitride LED phosphor SSDR660 produced by Yantai Shield Material Technology Co., Ltd., with a density of 3.2 g / cm 3 , D50 particle size 15.0±2.0μm; The light green phosphor a is the rare earth aluminate LED phosphor SDIR700 produced by Yantai Hild Materials Technology Co., Ltd., with a density of 3.9 g / cm 3 , D50 particle size 21.0±2.0μm; The light green phosphor b is the rare earth aluminate LED phosphor SDIR760 produced by Yantai Hild Materials Technology Co., Ltd., with a density of 3.9 g / cm 3 , D50 particle size 22.0±2.0μm; The light green phosphor c is the rare earth aluminate LED phosphor SDIR800 produced by Yantai Hild Materials Technology Co., Ltd., with a density of 3.9 g / cm 3 , D50 particle size 18.0±2.0μm.

2. A high color rendering index and high stability LED device, characterized in that: It comprises an LED chip with a peak emission wavelength range of 430-435nm, 450-452nm and 460-470nm, and a phosphor glue for encapsulating the LED chip; the phosphor glue comprises an LED potting glue and a phosphor composition dispersed therein; the phosphor composition is the phosphor composition according to claim 1; the color rendering index of the high color rendering index and high stability LED device is Ra≥99, R9≥99, and R15≥99.

3. The method for preparing a high color rendering index and high stability LED device according to claim 2, characterized in that: The method comprises the following preparation steps: (1) Surface modification of phosphor composition: The phosphor composition and the alkylbenzene sulfonate dispersant are added to an ethanol aqueous solution and stirred to disperse uniformly, then the temperature is raised to 70-85° C., an acid catalyst and a silicate compound are added dropwise and stirred to react for 1-4 hours, and then a vinyl silane coupling agent is added and stirred to react for 0.5-2 hours, and the product is filtered, washed, and dried to obtain a vinyl surface-modified phosphor composition; (2) Preparation of silicone LED potting glue: The phenyl vinyl silicone oil, hydrogen-containing silicone oil, inhibitor and catalyst are stirred and mixed evenly to obtain an organic silicone LED potting adhesive; (3) Preparation of phosphor glue: The vinyl surface-modified phosphor composition of step (1) and the organosilicon LED potting glue of step (2) are mixed and stirred evenly, and allowed to stand or degas in vacuum to obtain phosphor glue; (4) LED chip packaging and curing: The LED chip is encapsulated by injecting the phosphor glue in step (3), and then heated, baked and cured to obtain a high color rendering index and high stability LED device.

4. The method for preparing a high color rendering index and high stability LED device according to claim 3, characterized in that: The alkylbenzene sulfonate dispersant in step (1) is sodium dodecylbenzene sulfonate, and the amount of the alkylbenzene sulfonate dispersant added is 1% to 4% of the mass of the phosphor composition; the ethanol aqueous solution refers to an ethanol aqueous solution with an ethanol mass fraction of 70% to 90%.

5. The method for preparing a high color rendering index and high stability LED device according to claim 3, characterized in that: The acid catalyst in step (1) is hydrochloric acid; the silicate compound is ethyl orthosilicate or isopropyl orthosilicate, and the amount of the silicate compound added is 4% to 20% of the mass of the phosphor composition.

6. The method for preparing a high color rendering index and high stability LED device according to claim 3, characterized in that: The vinyl silane coupling agent in step (1) is vinyl triethoxy silane or vinyl trimethoxy silane, and the amount of the vinyl silane coupling agent added is 2% to 10% of the mass of the phosphor composition.

7. The method for preparing a high color rendering index and high stability LED device according to claim 3, characterized in that: The phenyl content of the phenyl vinyl silicone oil in step (2) is 5% to 30%, and the vinyl content is 2% to 10%; the viscosity of the phenyl vinyl silicone oil is 1000 to 4000 mPa.s; the hydrogen content of the hydrogen-containing silicone oil is 0.1% to 0.6%; the viscosity of the hydrogen-containing silicone oil is 100 to 2000 mPa.s; and the mass of the hydrogen-containing silicone oil is 10% to 40% of the mass of the phenyl vinyl silicone oil.

8. The method for preparing a high color rendering index and high stability LED device according to claim 3, characterized in that: In step (2), the inhibitor is an acetylenic alcohol inhibitor, and the mass of the inhibitor is 0.02% to 0.2% of the mass of the phenyl vinyl silicone oil; the catalyst is a Karstedt catalyst, and the mass of the catalyst is 0.005% to 0.02% of the mass of the phenyl vinyl silicone oil.

9. The method for preparing a high color rendering index and high stability LED device according to claim 3, characterized in that: The mass percentage of the vinyl surface modified phosphor composition in the phosphor glue in step (3) is 5% to 20%; the heating and baking curing in step (4) refers to first baking at 70 to 90° C. for 1 to 2 hours, and then heating to 150 to 160° C. for 4 to 5 hours.

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