KR102394051B1 - Composition for Manufacturing Ceramic Fluorescent Plate, Ceramic Fluorescent Plate and Light Emitting Apparatus - Google Patents

Abstract

The present invention, a phosphor; glass frit; And it relates to a composition for preparing a phosphor plate comprising K2SiO3.
According to an embodiment of the present invention, a composition for producing a phosphor plate in which the luminous flux is increased by reducing the interface between glass frits to prevent light loss, and a phosphor plate prepared using the composition for producing the phosphor plate and the plate An applied light emitting device can be provided.

Description

A composition for manufacturing a phosphor plate, a phosphor plate, and a lighting device {Composition for Manufacturing Ceramic Fluorescent Plate, Ceramic Fluorescent Plate and Light Emitting Apparatus}

An embodiment of the present invention relates to a composition for manufacturing a phosphor plate, a phosphor plate, and a light emitting device, and more particularly, to a ceramic phosphor plate capable of increasing luminous flux by minimizing the interface between glass frits using an inorganic binder It relates to a composition, a ceramic phosphor plate, and a light emitting device.

Light emitting diodes (LEDs), which have recently emerged as a promising next-generation light source, are considered as potential replacement light sources for conventional lighting devices due to their low electricity consumption, high brightness, long lifespan and environmentally friendly devices. White LED was developed by S. Nakamura of Japan. First, a blue LED chip was developed, making it possible to realize the light of the entire visible ray region as an LED. White light is produced by combining a yellow fluorescent substance with a blue LED. This method was first developed and is the most commonly used white LED. In addition, there is a method in which red, green, and blue LEDs are combined or two or more types of phosphors are combined. Epoxy has been mainly used as an LED encapsulant for phosphor application, but recently, a lot of development of a silicone encapsulant having a high refractive index, high hardness, and process efficiency has been made. However, since silicon material is an organic material and has limitations in heat resistance and UV resistance, ceramic plate phosphors are emerging recently. Ceramic plate phosphors include a ceramic sintered type, a crystallized glass type, and a glass powder sintered type. Among them, the glass powder sintering type can be viewed as the most promising technology because the content of phosphors can be freely adjusted and different kinds of phosphors can be freely mixed and used to control color coordinates and color rendering index.

On the other hand, sintered glass has a disadvantage in that the transmittance is lower than that of melting glass. That is, the PiG (Phosphor in Glass) type ceramic phosphor plate is produced by press-molding a mixture of glass frit and phosphor and then sintering. In the case of sintered glass, an interface between glass frits exists and this The transmittance is lowered by the interface, and light loss occurs.

In addition, when manufacturing the PiG type ceramic phosphor plate, a binder is used to increase the yield of the green body manufacturing process. When an organic binder is used, transmittance and luminous flux decrease, and by reaction with xanthan or phosphor, The disadvantage is that the speed of light decreases.

Embodiments of the present invention have been devised to solve the above problems, and it is possible to provide a composition for manufacturing a phosphor plate in which the luminous flux is increased by preventing light loss by reducing the interface between glass frits. In addition, it is possible to provide a phosphor plate manufactured using the composition for producing a phosphor plate and a lighting device to which the plate is applied.

An embodiment of the present invention is to achieve the above object, a phosphor; SiO ₂ -B ₂ O ₃ -ZnO-based glass frit (glass frit); And it provides a composition for preparing a phosphor plate comprising K2SiO3.

In addition, the content of the K2SiO3 is characterized in that 1 to 4% by weight.

In addition, the content of the glass frit is characterized in that 61 to 88% by weight.

In addition, the glass frit is characterized in that the total amount of SiO ₂ , B ₂ O ₃ and ZnO ₃ is 40 to 80% by weight based on the total amount of the glass frit.

In addition, the composition is characterized in that it further comprises at least one selected from the group consisting of Na ₂ O, Li ₂ O, and K ₂ O.

In addition, the phosphor is a LuAG, LuYAG, YAG, or nitride-based phosphor having an emission wavelength of 540 to 570 nm.

In addition, the phosphor is characterized by using a mixture of two types of a LuAG, LuYAG, YAG, or nitride-based phosphor having an emission wavelength of 540 to 570 nm and a SiAlON-based phosphor having an emission wavelength of 580 to 630 nm.

In addition, the content of the phosphor is characterized in that 0.01 to 15% by weight.

In addition, the glass frit is characterized in that the average particle size is 2㎛ or more.

In addition, an embodiment of the present invention is to achieve the above object, and provides a phosphor plate prepared by sintering the composition after compression molding.

In addition, an embodiment of the present invention is to achieve the above object, and provides a light emitting device including a phosphor plate.

According to an embodiment of the present invention, a composition for producing a phosphor plate in which the luminous flux is increased by reducing the interface between glass frits to prevent light loss, and a phosphor plate prepared using the composition for producing the phosphor plate and the plate An applied light emitting device can be provided.

1 schematically shows a manufacturing process of a glass frit.
FIG. 2 is a photograph of an image of measuring optical characteristics by assembling a phosphor plate measuring jig.
3 is a graph showing the result of analyzing glass alone and transmittance at a thickness of 1T using a UV-vis spectrometer.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment in which a person of ordinary skill in the art to which the present invention pertains can easily practice the present invention will be described in detail. However, it should be understood that the configuration shown in the embodiments and drawings described in this specification is only a preferred embodiment of the present invention, and there may be various equivalents and modifications that can be substituted for them at the time of the present application. . In addition, in the detailed description of the operating principle of the preferred embodiment of the present invention, if it is determined that a detailed description of a related well-known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. The terms described below are terms defined in consideration of functions in the present invention, and the meaning of each term should be interpreted based on the content throughout this specification. The same reference numerals are used throughout the drawings to refer to parts having similar functions and functions.

Embodiments of the present invention, a phosphor; glass frit; And K ₂ SiO ₃ It relates to a composition for producing a phosphor plate comprising.

An embodiment of the present invention is to improve the transmittance of the glass frit and the luminous flux of the phosphor plate by minimizing the microinterface of the sintered body of the conventional PIG-type phosphor plate. For this purpose, it is characterized in that an inorganic binder is used to improve the luminous flux by increasing the wettability between the phosphor and the glass frit.

The PIG type phosphor plate is manufactured by manufacturing and sintering a green body with a mixture of glass frit and phosphor, but since it is not a complete melting glass, an interface exists between the glass frits.

1 schematically shows a manufacturing process of a glass frit. The manufactured glass frit has a high transmittance, but when the glass frits are made of sintered glass, the interface between the frits does not completely disappear, so the transmittance is lowered.

The phosphor plate according to the present invention minimizes the interface between glass frits by using potassium silicate (K ₂ SiO ₃ ) as an inorganic binder when manufacturing a green body. . The content of adding the binder to the mixture of the glass frit and the phosphor is in the range of 1 to 4 wt%. When an amount less than 1 wt% is added, it is not preferable because it is an insufficient amount to improve wettability at the interface of the added phosphor. can't

By minimizing the interface between the glass frits, the transmittance of the glass matrix is increased, and as a result, the luminous flux of the phosphor plate can be improved.

Potassium silicate's K component is an alkali element and plays a role in improving the luminous flux by increasing wettability with fluorescent agents.

The composition for manufacturing a phosphor plate according to the present invention uses 61% to 88% by weight of glass frits of SiO ₂ -B ₂ O ₃ -ZnO-based composition, and the main glass composition is SiO ₂ , B ₂ O ₃ , It is ₃ types of ZnO, and the total of the 3 types is preferably included in the range of 40 to 80 weight% of the total glass frit. When less than 40% by weight is contained, it is not preferable because reliability problems (physical strength decrease, elution of glass component ions, etc.) occur because the basic skeleton of the glass is not dense. It is undesirable because the content of the components that play a role such as increasing the transmittance and whiteness of the product is insufficient.

Furthermore, the glass frit may have an average particle diameter of 1 μm to 20 μm, preferably 2 μm to 15 μm. When the particle size of the glass frit is reduced, the internal porosity after sintering is reduced, which is advantageous for improving optical properties. When the particle diameter of the glass frit exceeds 20 μm, there is a fear that a plurality of pores may be formed when mixed with a phosphor and sintered later. On the other hand, when the particle diameter of the organic frit is less than 1 μm, there is a risk that the phosphor may not be sufficiently dispersed when mixed with the phosphor, so that the phosphor cannot be sufficiently passivated. It becomes difficult to maintain whiteness.

In addition, an alkali (Na ₂ O, Li ₂ O, K ₂ O) element may be further added to the composition for preparing a phosphor plate according to the present invention for calcination at 650° C. or less, and the content to be added may include 10 to 20% by weight. there is.

One embodiment of the present invention relates to a phosphor plate manufactured by mixing and sintering an inorganic binder with the glass frit and phosphor mixture.

The phosphor that can be used can be used by mixing one or more kinds, and when one kind is mixed, a LuAG, LuYAG, YAG, Nitride-based phosphor having an emission wavelength of 540 to 570 nm can be used, and when two kinds are mixed, the above 1 A SiAlON-based phosphor having an emission wavelength of 580 to 630 nm can be added to the phosphor used for species mixing.

The content of the phosphor may be added in an amount of 0.01 to 15% by weight.

In addition, an embodiment of the present invention may provide a lighting device to which a phosphor plate manufactured by mixing and sintering the glass frit and the phosphor mixture with an inorganic binder is applied.

3 shows a lighting device to which a plate-formed structure is applied using the phosphor composition according to the present invention.

Referring to FIG. 3 , the lighting device according to the present embodiment includes a ceramic phosphor plate 2200 manufactured by using the phosphor composition according to the above-described embodiments. In this case, the ceramic phosphor plate 2200 is provided to be spaced apart from the light source 2100 . The distance from the light source may be 10 mm to 20 mm. The separation distance may be preferably 12 mm to 18 mm. When the separation distance exceeds 20 mm, there is a fear that light extraction is not sufficiently performed. On the other hand, when the separation distance is less than 10 mm, there is a risk that the ceramic phosphor plate 2200 may be thermally deformed by the heat generated from the light source 2100 . In this structure, as in the embodiment of the present invention, the phosphor plate is implemented with a material including a phosphor, a glass frit having a SiO ₂ -B ₂ O ₃ -ZnO-based composition, and K ₂ SiO ₃ . By reducing the interface between (glass frit) and preventing light loss, it is possible to increase the luminous flux.

In addition, the lighting device according to the present embodiment includes a housing 2300 having a shape that becomes wider from the bottom to the top with the light source 2100 as the center. As the light source 2100 , as an optical device emitting light, for example, a solid-state light emitting device may be applied. As the solid-state light emitting device, any one selected from among LED, OLED, LD (laser diode), Laser, and VCSEL may be applied. A ceramic phosphor plate 2200 is provided at the upper end of the housing 2300 , and is disposed to be spaced apart from the light source 2100 . The ceramic phosphor plate 2200 includes a matrix made of glass frit and a ceramic phosphor dispersed in the matrix as described above. The inside of the housing may be filled with a material having a refractive index equal to or higher than that of the ceramic phosphor plate 2200 .

In addition, optical properties can be measured with this type of integrating sphere. The luminance of the integrating sphere is constant at any angle, and all of the light reflected from the surface of the sample is captured and distributed on the surface of the integrating sphere with an even illuminance. As a coating material for the inner wall of the integrating sphere, there are special paints or polytetrafluoroethylene (PTFE, polytetrafluoroethylene), etc., and be careful not to contaminate the inside. In the case of spectral transmittance, the light transmitted without a sample is set to 100%, and when the light is completely blocked by an opaque object such as an iron plate, it is set to 0%. When the dispersion effect in the transmissive material among the transmissive colors is large, it is preferable to measure using an integrating sphere.

The integrating sphere is prepared in a size of 55 mm to 60 mm W _T , 35 mm to 40 mm W _B , and 15 mm to 20 mm H. First, in the absence of the ceramic phosphor plate 2200 , a radiant flux of the blue LED, which is the light source 2100 , is measured. Thereafter, the luminous efficiency can be obtained by mounting the ceramic phosphor plate 2200 to measure the luminous flux and dividing by the previously measured value of the luminous flux of the blue LED.

Hereinafter, the present invention will be described in more detail through examples. These examples are only for illustrating the present invention in more detail, and it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples according to the gist of the present invention. .

[Example]

1. Glass manufacturing process

1) Oxide raw material

2) Mixing through Ball Mill (48hr)

3) Put the mixed powder in a platinum crucible and melt (1300℃, 30 minutes)

4) Pour the glass melt into the twin roller and proceed with quenching (manufacture of glass cullet)

5) Glass frit is manufactured by pulverizing the manufactured glass cullet to a desired particle size using a ball mill, a jet mill, etc.

2. Phosphor plate manufacturing process

1) material mixing

- In case of 3000K color temperature: 550nm LuAG:Ce phosphor 7wt%, 620nm Nitride phosphor 2wt% mixture

- 5700K color temperature realization: 550nm LuAG:Ce phosphor 15wt%, 590nm Nitride phosphor 1.5wt% mixture

2) Compression molding (press)

- Press the powder mixed in Sus mold uniaxially at room temperature (5 Ton, 3 minutes)

3) sintering

- Put the green body that has undergone the press process into the sintering furnace and sinter step by step (1st sintering: ~250℃, 1hr / 2nd sintering: sintering conditions vary depending on Glass Tg)

4) Polishing

- Polishing the surface of the plate through polishing (thickness processing): thickness of 100 ~ 200㎛

- Mirror finish with a surface roughness of 0.2 ~ 7㎛

3. Measurement of the phosphor plate luminous flux

1) Process the phosphor plate to a diameter of 24mm and a thickness of 120㎛

2) As shown in FIG. 2, it was assembled on a jig for measuring the phosphor plate to measure optical properties (FIG. 2a: Remote type, FIG. 2b: Conformal type)

[Experiment result]

1. Evaluation of transmittance of glass matrix

In order to evaluate the transmittance of the glass matrix, a green body was manufactured and sintered by adding a potassium silicate binder to the glass frit without mixing a phosphor, and the transmittance was measured (Comparative Example).

A green body was prepared by adding 1 to 10 wt% of potassium silicate binder to the glass frit, and the transmittance was measured by sintering (Examples 1 to 6).

Sintered in an air atmosphere using a general box furnace. (temperature increase rate 10℃/min, 620℃ 30 minutes sintering, furnace cooling)

4 is a graph showing the results of analyzing glass alone and transmittance at a thickness of 1T using a UV-vis spectrometer.

Binder content (wt%) Transmittance (%) comparative example 0 57.0 Example 1 One 58.1 Example 2 2 62.1 Example 3 3 63.5 Example 4 4 69.8 Example 5 5 54.0 Example 6 10 41.5

When 1 to 4 wt% of a potassium silicate binder is added, the transmittance improvement effect can be confirmed.

2. Evaluation of optical properties of phosphor plates

1) Remote Type

Sample Size: 24Φ, thickness 120㎛

Chip: 443~446nm, 500~510mW (@350mA)

Applied current: 1,200 mA

Separation distance between Chip & Plate: 4mm

comparative example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Luminous flux (lm) 1018 1021 1027 1027 1030 994 955 color coordinates
Cx 0.3169 0.3202 0.3295 0.3242 0.3239 0.3262 0.3239 Cy 0.3323 0.3281 0.3262 0.3267 0.3350 0.3311 0.3317

2) Conformal Type

Sample Size : 0.98㎛*0.98㎛ 2 Wire, 120㎛ thickness

Chip : 443~446nm, 500~510mW (@350mA) (3535 1chip PKG)

Applied Current: 1500mA

comparative example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Luminous flux (lm) 260 266 271 271 275 257 231 color coordinates
Cx 0.3026 0.3065 0.3036 0.3079 0.3049 0.3065 0.3069 Cy 0.3098 0.3173 0.3098 0.3185 0.3152 0.3184 0.3189

3. Final Comparison of Glass Matrix

comparative example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Al ₂ O ₃ 3.0 3.0 2.9 2.9 2.9 2.9 2.7 B ₂ O ₃ 14.0 13.9 13.7 13.6 13.5 13.3 12.7 ZnO 30.0 29.7 29.4 29.1 28.8 28.6 27.3 SiO ₂ 25.0 25.1 25.5 25.7 26.0 26.1 27.3 P ₂ O ₅ 11.5 11.4 11.3 11.2 11.1 11.0 10.5 Na ₂ O 2.0 2.0 2.0 1.9 1.9 1.9 1.8 Li ₂ O 1.5 1.5 1.5 1.5 1.4 1.4 1.4 K ₂ O 10.0 10.4 10.8 11.2 11.5 11.9 13.6 SnO ₂ 3.0 3.0 2.9 2.9 2.9 2.9 2.7 Total 100.0 100.0 100.0 100.0 100.0 100.0 100.0 Transmittance@1T(%) 57.0 58.1 62.1 63.5 69.8 54.0 41.5 Luminous flux (lm) 1018 1021 1027 1027 1030 994 955

When ~4 wt% of the potassium silicate binder was added, the transmittance and luminous flux were increased. In particular, it was confirmed from the experiment that the transmittance and luminous flux increase effect was large when the binder content was 2 to 4 wt%.

2100: light source
2200: ceramic phosphor plate
2300: housing

Claims (11)

light source;
a phosphor plate spaced apart from the light source; and
Including; a housing for accommodating the light source and the phosphor plate;
The phosphor plate includes a phosphor, a glass frit of a SiO ₂ -B ₂ O ₃ -ZnO-based composition, and K ₂ SiO ₃ ,
The content of the K ₂ SiO ₃ is 1 to 4% by weight based on the weight of the phosphor plate,
The content of the glass frit is 61 to 88% by weight based on the weight of the phosphor plate.
According to claim 1,
In the glass frit, the total amount of SiO2, B2O3 and ZnO3 is 40 to 80 wt% based on the total amount of the glass frit.
According to claim 1,
The phosphor includes a LuAG, LuYAG, YAG, or nitride-based phosphor having an emission wavelength of 540 to 570 nm.
According to claim 1,
The phosphor is a lighting device using a mixture of two types of a LuAG, LuYAG, YAG, or nitride-based phosphor having an emission wavelength of 540 to 570 nm and a SiAlON-based phosphor having an emission wavelength of 580 to 630 nm.
5. The method according to claim 3 or 4,
The content of the phosphor is 0.01 to 15% by weight based on the weight of the phosphor plate.
5. The method of claim 3 or 4,
The glass frit has an average particle size of 2 μm or more.
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