JP2020111867A - Fluorescent substance-containing thermoplastic resin filament - Google Patents

Abstract

SOLUTION: There is provided a fluorescent substance-containing thermoplastic resin filament which is a raw material filament for producing a wavelength conversion member containing a fluorescent substance converting a wavelength of light emitted from an LED to emit light having a different wavelength by a 3D printer according to a melt lamination method, in which a particulate fluorescent substance containing a manganese-activated complex fluoride fluorescent substance represented by A2(M1-x, Mnx)F6 is dispersed, at a concentration of 30 mass% or less, in a thermoplastic resin selected from an olefin resin, a cyclic polyolefin resin, an acrylic resin, a styrene resin and an acryl-imide resin.EFFECT: A wavelength conversion member used for an LED light-emitting device of a remote phosphor type can efficiently be produced without using a metal die, and a fluorescent substance of the resultant wavelength conversion member has a good dispersibility.SELECTED DRAWING: Figure 1

Description

The present invention relates to a phosphor-containing thermoplastic resin filament suitable for producing a wavelength conversion member containing a phosphor that emits light of different wavelengths by converting the wavelength of light emitted from an LED.

A general white LED includes a blue LED element and a phosphor that converts light emitted from this element into a visible light component having a longer wavelength. In such a white LED, light having a longer wavelength than blue light generated by wavelength conversion of blue light that is excitation light incident on the phosphor is combined with blue light that is not absorbed by the phosphor. As a result, white light is generated. With white LEDs, characteristics such as chromaticity, color temperature, and luminous efficiency of emitted light largely depend on the type and concentration of the phosphor, and the characteristics of the emitted light are usually adjusted by the type and concentration of the phosphor. To be done.

Japanese Patent Publication No. 2015-520494 Japanese Patent Publication No. 2015-515734 Japanese Patent Publication No. 2013-521614

In such an LED light emitting device, light emission characteristics such as chromaticity, color temperature, and light emission efficiency of emitted light change depending on the shape and thickness of the wavelength conversion member. Since the phosphor used for such a wavelength conversion member is relatively expensive, it is required to reduce the amount used, but it is necessary to improve the light emission characteristics by the shape and thickness of the wavelength conversion member. In order to reduce the usage amount of the phosphor, in the LED package in which the phosphor is dispersed in the sealing material such as the resin that seals the LED element, the shape and thickness of the sealing material forming the wavelength conversion member are increased. There is a limit because it cannot be changed.

On the other hand, if the LED device is a remote phosphor type LED light emitting device that uses a wavelength conversion member formed as a member different from the LED package in which the LED device is sealed with a sealing material, the wavelength conversion member It is possible to obtain higher emission characteristics with a smaller amount of phosphor by changing the shape and thickness of the LED element or the arrangement of the wavelength conversion member with respect to the LED element or the LED element package. High degree of freedom to change.

However, in order to manufacture wavelength conversion members of various shapes and study the optical characteristics thereof, it is necessary to prepare a large number of molds in the manufacturing method using a normal mold, which increases the cost. Further, in the method of manufacturing the wavelength conversion member, sufficient optical characteristics required for the wavelength conversion member cannot be obtained unless the wavelength conversion member in which the phosphor is uniformly dispersed can be manufactured.

The present invention has been made in view of the above circumstances, with a smaller amount of phosphor, higher emission characteristics, in particular, a wavelength conversion member that can give higher emission efficiency, without using a mold, To provide a phosphor-containing thermoplastic resin filament that can be manufactured in a state where the dispersibility of the phosphor is high, that is, the phosphor is uniformly dispersed in the entire wavelength conversion member and the dispersion of the phosphor concentration is suppressed. To aim.

In order to solve the above-mentioned problems, the present inventors convert a wavelength of light emitted from an LED as a wavelength conversion member used in a remote phosphor type LED light emitting device, and emit light having a wavelength different from this wavelength. In examining the shape and thickness of the wavelength conversion member containing the phosphor that emits light, the arrangement of the wavelength conversion member with respect to the LED, etc., the inventors have earnestly studied how to efficiently manufacture the wavelength conversion member without using a mold. As a result, the wavelength conversion member that converts the wavelength of the light emitted from the LED and contains the phosphor that emits the light of a wavelength different from the wavelength is 30% by mass in the thermoplastic resin with the particulate phosphor in the thermoplastic resin. It has been found that a wavelength conversion member can be manufactured in a state in which the dispersibility of the phosphor is high by using a thermoplastic resin filament containing a phosphor dispersed in the following concentrations to produce it with a 3D printer by the melt lamination method. ..

Then, the present inventors, the phosphor-containing thermoplastic resin filament, after mixing the particulate phosphor into the thermoplastic resin to obtain a phosphor-containing thermoplastic resin,
(1) Extruding the phosphor-containing thermoplastic resin with a ratio (L/D) of the effective screw length L to the melting screw diameter D of 30 or more and 60 or less, or (2) the phosphor-containing thermoplastic resin, While extruding from an orifice hole in a molten state at a temperature of 180°C or higher and lower than 240°C, and stretching at a linear velocity of 3 times or more and 30 times or less with respect to the linear velocity of extrusion of the molten phosphor-containing thermoplastic resin By taking out extrusion molding, the dispersibility of the phosphor in the phosphor-containing thermoplastic resin filament is increased, and thus the phosphor-containing thermoplastic resin filament obtained is used to produce a 3D printer by the melt lamination method. The present invention has been completed by finding that the wavelength conversion member also has a high dispersibility of the phosphor.

Therefore, the present invention provides the following phosphor-containing thermoplastic resin filaments.
Claim 1:
A raw material filament for converting a wavelength of light emitted from an LED to produce a wavelength conversion member containing a phosphor that emits light of a wavelength different from the wavelength by a 3D printer by a melt lamination method, and particles. The above-mentioned fluorescent substance is dispersed in a thermoplastic resin at a concentration of 30% by mass or less,
The phosphor is A ₂ (M _1-x , Mn _x )F ₆ (wherein A is selected from Li, Na, K, Rb and Cs, and contains at least Na and/or K. At least one alkali metal, M is at least one tetravalent element selected from Si, Ti, Zr, Hf, Ge and Sn, and x is a positive number in the range of 0.001 to 0.3. A) containing a manganese-activated double-fluoride phosphor represented by
The phosphor-containing thermoplastic resin filament, wherein the thermoplastic resin is selected from an olefin resin, a cyclic polyolefin resin, an acrylic resin, a styrene resin, and an acrylimide resin.
Claim 2:
The manganese-activated double fluoride phosphor is represented by K ₂ (Si _1-x , Mn _x )F ₆ (where x is a positive number in the range of 0.001 to 0.3). The phosphor-containing thermoplastic resin filament according to claim 1, which is an activated potassium fluorosilicate phosphor.
Claim 3:
The phosphor-containing thermoplastic resin filament according to claim 1 or 2, wherein the thermoplastic resin is selected from acrylic resin, polystyrene, styrene copolymer, polyethylene, polypropylene and ethylene-propylene copolymer.

ADVANTAGE OF THE INVENTION According to this invention, the wavelength conversion member used for a remote phosphor type LED light-emitting device can be manufactured efficiently, without using a metal mold|die, and also the dispersibility of the fluorescent substance of the obtained wavelength conversion member is favorable. Is.

It is a figure which shows an example of the wavelength conversion member (No. 1) of this invention produced in Example 1, (A) is a perspective view, (B) is sectional drawing. It is a figure which shows an example of the wavelength conversion member (No. 2) of this invention produced in Example 1, (A) is a perspective view, (B) is sectional drawing. It is a figure which shows an example of the wavelength conversion member (No. 3) of this invention produced in Example 1, (A) is a perspective view, (B) is sectional drawing. 1 is an exploded perspective view showing an example of a remote phosphor type LED light emitting device of the present invention manufactured by using a wavelength conversion member (No. 1) in Example 1. FIG.

Hereinafter, the present invention will be described in more detail.
The wavelength conversion member of the present invention contains a phosphor that converts the wavelength of light emitted from an LED and emits light of a wavelength different from this wavelength. In the present invention, the LED may be an LED element only, that is, an LED semiconductor chip only, but normally, the LED element (LED semiconductor chip) is installed on a base material or a substrate, and a lead wire, An LED package sealed with a sealing material such as a resin is used together with a wiring member such as a terminal. As the LED package, a package that does not include a phosphor that converts the wavelength of light emitted from the LED element and emits light having a wavelength different from this wavelength is usually used in the sealing material. A material containing a phosphor may be used.

The LED emits visible light such as red LED whose emitted light is red light, green LED whose emitted light is green, blue LED whose emitted light is blue, yellow LED whose emitted light is yellow, and white LED whose emitted light is white. A blue LED, which emits blue light having a peak wavelength of 440 to 470 nm, is preferable.

The type of phosphor can be appropriately selected according to the wavelength of the excitation light emitted by the LED and the color of the light emitted from the LED light emitting device. For example, when a blue light emitting diode is used, a phosphor used to configure an LED light emitting device that emits white light using the blue light emitting diode is suitable. Examples of such a phosphor include phosphors that emit yellow, green, orange, red, or other light when excited by blue light that is excitation light. _{Specifically, Y 3 Al 5 O 12:} Ce, (Y, Gd) 3 (Al, Ga) 5 O 12, (Y, Gd) 3 Al 5 O 12: Ce, Lu 3 Al 5 O 12: Ce , (Lu,Y) ₃ Al ₅ O ₁₂ :Ce, Y ₃ (Al,Ga) ₅ O ₁₂ :Tb, (Sr,Ca,Ba) ₂ SiO ₄ :Eu, β-SiAlON:Eu, etc. Alternatively, a green phosphor may be used.

Further, when a low color temperature of 5000 K or less is required, a red phosphor can be used together with a yellow phosphor or a green phosphor. Examples of the red phosphor include CaAlSiN:Eu ²⁺ , Sr-CaAlSiN ₃ :Eu ^{3+, and the} like, and particularly in the case of a white LED light-emitting device having excellent color rendering properties, a manganese-activated double fluoride phosphor. Is preferably used.

The manganese-activated double-fluoride phosphor has a structure in which a part of the constituent elements of the double-fluoride is replaced with manganese (Mn), which is an activating element. For example, A ₂ MF ₆ (wherein A is Li , Na, K, Rb and Cs, and one or more alkali metals containing at least Na and/or K, M is one selected from Si, Ti, Zr, Hf, Ge and Sn, or A compound having a structure in which a part of the constituent elements of the double fluoride represented by 2 or more kinds of tetravalent elements) is substituted with manganese (Mn) which is an activator element. As such, A ₂ (M _1-x , Mn _x )F ₆ (In the formula, A and M are the same as above, and x is a positive number in the range of 0.001 to 0.3. The manganese-activated double fluoride phosphor represented by The manganese-activated double fluoride phosphor has a structure in which a part of the site of the tetravalent element represented by M is replaced with manganese, that is, a structure in which tetravalent manganese (Mn ⁴⁺ ) is replaced. ^Therefore , it may be expressed as A ₂ MF ₆ :Mn ⁴⁺ . In the present invention, among such manganese-activated double fluoride phosphors, K ₂ (Si _1-x , Mn _x )F ₆ (where x is the same as above) in which A is K and M is Si Manganese activated potassium fluorosilicate phosphor (generally referred to as KSF phosphor) represented by (.

The KSF phosphor is excited by blue light and emits fluorescence having an emission peak or a maximum emission peak in the wavelength range of 600 to 660 nm. On the other hand, the light absorption characteristics of the KSF phosphor are different from those of the red phosphors such as CaAlSiN:Eu ²⁺ and Sr-CaAlSiN ₃ :Eu ³⁺ described above, and the absorptance is sharply reduced when the wavelength is longer than 460 nm. .. Therefore, when a blue-green LED that emits a blue-green light having a peak wavelength around 460 nm is used as an excitation source for auxiliary excitation light, absorption/attenuation of auxiliary excitation light can be reduced, which is particularly effective. ..

In general, it is preferable to use a phosphor having a particle shape (for example, an average particle diameter D50 (volume basis) of 1 μm or more, particularly 2 μm or more, 30 μm or less, particularly 18 μm or less). The wavelength conversion member can be composed only of the phosphor (for example, it can be obtained by a method of molding and sintering the particulate phosphor). An inorganic or organic transparent material or a semi-transparent material, specifically, an inorganic material such as glass, or an organic material such as an organic polymer material such as resin, rubber, or elastomer, which is dispersed, is preferable. It is preferable that the phosphor is uniformly dispersed in the transparent material or the semitransparent material that forms the base material of the wavelength conversion member.

As the transparent material or the semitransparent material, it is preferable to use a resin, particularly a hard resin, among the organic polymer materials. As the resin, a thermosetting resin such as a silicone resin or an epoxy resin or an ultraviolet curable resin, an olefin resin such as polyethylene or polypropylene, a cyclic polyolefin resin, an acrylic resin, polystyrene, an AS resin or a styrene resin such as an ABS resin, A thermoplastic resin such as an acrylic resin, a polycarbonate resin, or an ester resin such as a PET resin can be used, and a thermoplastic resin, particularly a hard thermoplastic resin is preferable.

In particular, when a manganese-activated double fluoride fluorescent material is used as the fluorescent material, among the thermoplastic resins exemplified above, resins other than ester-based resins are suitable. When a manganese-activated double fluoride phosphor and an ester resin are used, the resin may be dissolved or embrittled due to a hydrolysis reaction. On the other hand, in olefin resins such as polyethylene and polypropylene, cyclic polyolefin resins, acrylic resins, polystyrene, AS resins, styrene resins such as ABS resins, and acrylimide resins, manganese-activated double fluoride phosphors are used. Particularly effective kneading and high dispersibility can be obtained without causing the above problems.

The concentration of the phosphor in the wavelength conversion member is the kind of the phosphor used, the particle size, the kind of the transparent material or the semitransparent material, the color temperature and the thickness of the light emission obtained in the LED light emitting device, the LED element and the phosphor member The total amount of the phosphor is 2% by mass or more, particularly 3% by mass or more, and 30% by mass or less, particularly 20% by mass or less, and particularly 15% by mass or less, although it depends on the arrangement with and other conditions. preferable.

For example, when Y ₃ Al ₅ O ₁₂ :Ce phosphor is dispersed in a resin to form a wavelength conversion member having a thickness of 0.5 to 5 mm and white light having a color temperature of 6000 K is to be obtained, Y ₃ Al ₅ O _{12 is used.} The concentration of :Ce phosphor is approximately 2 to 8% by mass. More specifically, when a wavelength conversion member having a thickness of 2 mm is used and white light having a color temperature of 6000 K is to be obtained, the concentration of the Y ₃ Al ₅ O ₁₂ :Ce phosphor is approximately 4 to 6 mass %.

Further, Y ₃ Al ₅ O _12: with Ce phosphor, the case of using a manganese-activated double fluoride phosphors, the concentration of manganese activated double fluoride phosphor, Y ₃ Al ₅ O _12: the Ce phosphor, generally 2 ~4 times. Specifically, for example, a Y ₃ Al ₅ O ₁₂ :Ce phosphor and a manganese-activated double fluoride phosphor are dispersed in a resin to form a wavelength conversion member having a thickness of 0.5 to 5 mm and a color temperature of 3500K. When it is desired to obtain white light, the concentration of the Y ₃ Al ₅ O ₁₂ :Ce phosphor is approximately 2 to 5% by mass, and the concentration of the manganese-activated double fluoride phosphor is approximately 6 to 13% by mass. More specifically, when a wavelength conversion member having a thickness of 2 mm is used and white light having a color temperature of 3500 K is to be obtained, the concentration of the Y ₃ Al ₅ O ₁₂ :Ce phosphor is approximately 2 to 5% by mass and manganese activation is performed. The concentration of the double-fluoride phosphor is approximately 5 to 10% by mass.

Since the wavelength conversion member used for the remote phosphor type LED light emitting device is manufactured as a member different from the LED, the wavelength, the shape, the size, the arrangement with respect to the LED, etc. are determined according to the optical characteristics required for the LED light emitting device. It is possible to independently adjust the conversion member side. The wavelength conversion member of the present invention preferably has a thickness of 0.6 mm or more, particularly 1 mm or more, and 4 mm or less, particularly 2 mm or less. This is because if the thickness of the wavelength conversion member is smaller than 0.6 mm, the influence of the dimensional error becomes large and the influence of the dispersion of the dispersion of the phosphor is greatly affected, so that the optical characteristics of the entire wavelength conversion member are made uniform. If the thickness of the wavelength conversion member exceeds 4 mm, the amount of the phosphor increases and the utilization efficiency of the phosphor may decrease. It should be noted that the thickness usually refers to the effective thickness, that is, the thickness at the position where the excitation light from the LED directly enters.

To manufacture the wavelength conversion member, a hot melt lamination method (FDM method), which is a typical method of the 3D print molding method, is applied. The FDM method is a molding method in which a thermoplastic resin filament as a raw material is fed to a triaxially movable melting nozzle to extrude and laminate the thermomelted thermoplastic resin to obtain a resin molded product having a desired shape. Is. The FDM method is advantageous in manufacturing a wavelength conversion member having a shape in which manufacturing conditions are complicated because there is a restriction on mold release in a molding method using a mold, and since it is not necessary to prepare a mold, It is suitable for manufacturing a large number of small quantities of wavelength conversion members. The FDM method of obtaining a resin molded body of a desired shape by stacking and curing the heat-melted resin raw material while ejecting it from a nozzle is more effective than an injection molding method using a general mold. Is advantageous for molding a wavelength conversion member having a three-dimensional shape, especially a deeper three-dimensional inner surface.

In the FDM method, a fine linear filament (hereinafter, referred to as a phosphor-containing thermoplastic resin filament) in which predetermined phosphor particles are dispersed in a thermoplastic resin is used. The phosphor-containing thermoplastic resin filament can be manufactured by, for example, extrusion molding. The phosphor is kneaded into the thermoplastic resin at a predetermined concentration in the process of melt extrusion molding. In order to uniformly disperse the phosphor in the thermoplastic resin filament containing the phosphor, a twin screw type extrusion is used. The use of a molding machine is preferred. In addition, in order to prevent the inclusion of iron, etc. in the phosphor-containing thermoplastic resin filament due to abrasion due to the dispersed phosphor particles, extrusion molding using an inner wall or screw formed of a hard material such as cemented carbide or a non-ferrous material It is also effective to use a machine.

When manufacturing a phosphor-containing thermoplastic resin filament by extrusion molding, first, a particulate phosphor is mixed with a thermoplastic resin to obtain a phosphor-containing thermoplastic resin. After that, a phosphor-containing thermoplastic resin filament is manufactured by using an extrusion molding machine. At the time of extrusion molding, the phosphor-containing thermoplastic resin has a ratio (L/D) of the effective screw length L to the melting screw diameter D of 30. It is preferable to carry out extrusion molding as above 60 or less.

As a method for melting the thermoplastic resin while uniformly dispersing the phosphor particles in the thermoplastic resin without uneven distribution, kneading and melting with an extruder is effective, but the dispersibility of the phosphor particles is the melting screw diameter. It is affected by the ratio of the effective screw length L to D (L/D). The higher the L/D, the better the dispersibility of the phosphor particles in the thermoplastic resin, but if the L/D is too high, the productivity decreases. When extrusion molding a thermoplastic resin in which the phosphor is dispersed, good dispersibility can be obtained by setting L/D to 30 or more, particularly 40 or more. On the other hand, in the case of phosphor particles, if L/D is too high, the phosphor particles are strongly rubbed with the inner wall of the extrusion machine or the screw, and the device is worn, and the phosphor-containing thermoplastic resin filament has inner walls or screws. Since the component of the material may mix, it is preferably 60 or less, more preferably 50 or less.

Further, during extrusion molding, it is preferable to extrude the phosphor-containing thermoplastic resin from the orifice hole in a state of being melted at a temperature of 180° C. or higher, particularly 200° C. or higher, and lower than 240° C., particularly 235° C. or lower. By setting the temperature of the photoconductor-containing thermoplastic resin within the above range, the diameter dimension of the phosphor-containing thermoplastic resin filament, which is the wire, is stabilized. This temperature is usually about 10 to 40° C. lower than the operating temperature of the apparatus, that is, the average temperature of the melting region of the barrel.

Furthermore, during extrusion molding, the linear velocity of extrusion of the molten phosphor-containing thermoplastic resin (the linear velocity of discharge of the phosphor-containing thermoplastic resin filament), that is, three times or more the linear velocity at the orifice, It is also preferable to draw while drawing at a linear velocity of 5 times or more and 30 times or less, particularly 10 times or less. By setting the ratio of the linear velocity of the extrusion of the phosphor-containing thermoplastic resin to the linear velocity of the phosphor-containing thermoplastic resin filament withdrawing within the above range, the dispersion of the phosphor is partially unsatisfactory immediately after discharge. Even if there is a uniform part, the part is expanded and averaged by sufficient stretching, and the dispersion of the phosphor is homogenized, and the dispersion of the concentration of the phosphor in the phosphor-containing thermoplastic resin filament is suppressed. Can be suppressed. If the ratio of the linear velocity of the extrusion of the phosphor-containing thermoplastic resin and the linear velocity of the phosphor-containing thermoplastic resin filament take-up is too high, the relatively thin portion undergoes rapid drawing and becomes thinner, resulting in a thicker portion. Unevenness and filament breakage may occur.

When the wavelength conversion member is manufactured by the FDM method, it is possible to use the above-mentioned thermoplastic resin, but in addition to good dispersibility of the phosphor in the thermoplastic resin at the time of molding, rapid melting by predetermined heating, It is necessary to consider rapid hardening after lamination, welding characteristics between layers at the time of lamination, adhesion to the reference pedestal, durability against compressive stress accumulated inside the wavelength conversion member due to melting and hardening. From such a viewpoint, in the production of the wavelength conversion member by the FDM method, styrene copolymers such as acrylic resin, polystyrene, AS resin and ABS resin, polyethylene such as high density polyethylene, polypropylene, ethylene-propylene copolymer and the like. The thermoplastic resin of is particularly preferable.

The particle size of the phosphor dispersed in the phosphor-containing thermoplastic resin filament is set according to the type of the phosphor used, the particle shape thereof, and the resin material as the base material, and usually the average particle diameter D50 (volume basis). Is preferably 1 μm or more, particularly 2 μm or more, and 30 μm or less, particularly 18 μm or less. The concentration of the phosphor dispersed in the phosphor-containing thermoplastic resin filament is set according to the type of phosphor used and the emission chromaticity targeted by the wavelength conversion member after molding, and the total amount of phosphor is 2 It is preferably not less than 3% by mass, more preferably not less than 30% by mass, especially not more than 20% by mass, especially not more than 15% by mass. If the phosphor concentration is too high, there is a high possibility that the melting nozzle will be clogged, and there will be no stiffness during melting, and sagging may occur during molding. The diameter of the phosphor-containing thermoplastic resin filament is usually 1.75 mm or 3 mm in the currently used 3D printer to which the FDM method is applied.

When the phosphor-containing thermoplastic resin filament contains a large amount of water during the molding of the wavelength conversion member, when it is melted and laminated, water vapor is generated in the melting head, which becomes fine bubbles during lamination, There is a risk that the haze of the wavelength conversion member may be excessively increased, which may cause a change in optical characteristics, and the density may decrease. In particular, when the phosphor-containing thermoplastic resin filament is manufactured by extrusion molding, the phosphor-containing thermoplastic resin filament comes into contact with water through the cooling water tank, so Water may be taken in. Therefore, it is preferable to use the phosphor-containing thermoplastic resin filament after reducing the water content thereof. For example, the phosphor-containing thermoplastic resin filament is heated, for example, at a temperature of 70° C. or higher, particularly 80° C. or higher, preferably 100° C. or lower in a gas atmosphere such as an air atmosphere or a vacuum atmosphere for, for example, 6 hours or more. As a result, the amount of water can be reduced. The upper limit of the heating time is usually 24 hours or less. A heating furnace such as a vacuum furnace can be used for this heating.

In the FDM method, the wavelength conversion member may be molded by an FDM device (FDM3D printer) using the phosphor-containing thermoplastic resin filament. The inner diameter of the melting nozzle is suitably φ0.2 mm or more and φ0.6 mm or less. This is because when the inner diameter of the nozzle is less than φ0.2 mm, the melting nozzle is likely to be blocked by the phosphor, while when the inner diameter exceeds φ0.6 mm, the dimensional accuracy of the wavelength conversion member decreases. This is because it may be necessary to process the above. The temperature of the melting nozzle at the time of molding is preferably 190° C. or higher, particularly 220° C. or higher, and 280° C. or lower, particularly 260° C. or lower. If the temperature of the melting nozzle is less than the above range, the melting of the thermoplastic resin may be insufficient, while if it exceeds the above range, the stiffness during melting disappears, and the curing after lamination becomes slow, This is because sagging may occur during stacking.

The LED light-emitting device of the present invention includes an LED, a base on which the LED is installed, and a wavelength conversion member, and the wavelength conversion member is arranged so as to be separated from the LED via a gas layer or a vacuum layer. It is a phosphor type LED light emitting device. In the LED light-emitting device of the present invention, by using the wavelength conversion member of the present invention, the inner surface of the wavelength conversion member has a front side in the irradiation direction of the light emitted from the LED and a part of the side in the irradiation direction, or The wavelength conversion member is configured so as to surround the whole and, together with the substrate, form a space that includes the LED and that allows the light emitted from the LED to pass therethrough. As the LED light emitting device, an LED light emitting device that emits white light is particularly preferable, but an LED light emitting device that emits visible light such as red light, green light, blue light, and yellow light may be used.

Hereinafter, the present invention will be specifically described by showing experimental examples and examples, but the present invention is not limited to the following examples.

[Experimental Example 1]
YAG:Ce and KSF as phosphors were kneaded into an acrylic resin (Delpet 60N (manufactured by Asahi Kasei Co., Ltd.)) to obtain a YAG:Ce phosphor concentration of 2.8 mass% and a KSF phosphor concentration of 8. Pellets of 4% by mass of phosphor-containing thermoplastic resin were obtained. Next, the pellets were put into a twin-screw extruder TEM-18 (manufactured by Toshiba Machine Co., Ltd.), melt-kneaded at a barrel average heating temperature of 240° C., then the temperature was lowered to 220° C., and φ4. The phosphor-containing resin was extruded through a 5 mm orifice hole at a linear velocity of 1.1 m/min, and the discharged phosphor-containing resin was dipped in cold water. The filament was drawn at a linear velocity of 6.5 m/min, which was 6 times, and was made into a linear shape with an average diameter of 1.75 mm, and further heated in a vacuum furnace at 70° C. for 12 hours to obtain a phosphor-containing thermoplastic resin filament. .. The ratio (L/D) of the effective screw length L to the melting screw diameter D in this extrusion molding was 42.

In the obtained phosphor-containing thermoplastic resin filament, the diameter of each part was uniform, and the number of minute irregularly shaped parts (fish eyes) due to defective melting was about 1 in 150 m.

[Experimental Example 2]
YAG:Ce as a phosphor was kneaded into polypropylene (Noblen Z144 (manufactured by Asahi Kasei Co., Ltd.)) to obtain pellets of a phosphor-containing thermoplastic resin having a YAG:Ce phosphor concentration of 6% by mass. Next, the pellets were put into a twin-screw extruder TEM-18 (manufactured by Toshiba Machine Co., Ltd.), melt-kneaded at a barrel average heating temperature of 220° C., then the temperature was lowered to 180° C., and φ4. The phosphor-containing resin was extruded from a 5 mm orifice hole at a linear velocity of 0.6 m/min, and the discharged phosphor-containing resin was dipped in cold water. It was drawn at a linear velocity of 12 m/min, which was 20 times, to obtain a linear shape with an average diameter of 1.75 mm, and further heated in a vacuum furnace at 80° C. for 8 hours to obtain a phosphor-containing thermoplastic resin filament. The ratio (L/D) of the effective screw length L to the melting screw diameter D in this extrusion molding was 42.

In the obtained phosphor-containing thermoplastic resin filament, the diameter of each part was uniform, and the number of minute irregularly shaped parts (fish eyes) due to defective melting was about 1 per 300 m.

[Experimental Example 3]
YAG:Ce was kneaded as a phosphor into an acrylic resin (Delpet 60N (manufactured by Asahi Kasei Co., Ltd.)) to obtain pellets of a phosphor-containing thermoplastic resin having a YAG:Ce phosphor concentration of 7% by mass. Next, the pellets were put into a twin-screw extruder TEM-18 (manufactured by Toshiba Machine Co., Ltd.), melt-kneaded at a barrel average heating temperature of 250° C., then the temperature was lowered to 235° C., and φ4. The phosphor-containing resin was extruded through a 5 mm orifice hole at a linear velocity of 1.2 m/min, and the discharged phosphor-containing resin was dipped in cold water. The filament was drawn at a linear velocity of 18 m/min, which was 15 times, and a fluorescent substance-containing thermoplastic resin filament was obtained in a linear shape with an average diameter of 1.75 mm. The ratio (L/D) of the effective screw length L to the melting screw diameter D in this extrusion molding was 38.

In the obtained phosphor-containing thermoplastic resin filament, the diameter of each part was uniform, and the number of minute irregularly shaped parts (fish eyes) due to defective melting was about 1 per 200 m.

[Experimental Example 4]
Pellets of the phosphor-containing thermoplastic resin obtained by the same method as in Experimental Example 3 were charged into a twin-screw extruder TEM-18 (manufactured by Toshiba Machine Co., Ltd.) and melt-kneaded at a barrel average heating temperature of 240°C. Then, while maintaining the temperature, the resin containing phosphor was extruded from the orifice hole of φ4.5 mm at a linear velocity of 0.5 m/min, and the discharged phosphor-containing resin was dipped in cold water, and then the constant speed take-up machine IMC-19A5R(( (Made by Imoto Seisakusho Co., Ltd.) was drawn at a linear velocity of 1.3 m/min at which the draw ratio was 2.6 times, and a fluorescent substance-containing thermoplastic resin filament was obtained in a linear shape with an average diameter of 1.75 mm. The ratio (L/D) of the effective screw length L to the melting screw diameter D in this extrusion molding was 38.

In the obtained phosphor-containing thermoplastic resin filament, the diameter of each part was significantly varied from 1.5 to 1.9 mm, and continuous filaments having a constant diameter of 10 m or more could not be obtained.

[Experimental Example 5]
Pellets of the phosphor-containing thermoplastic resin obtained by the same method as in Experimental Example 1 were charged into a twin-screw extruder TEM-18 (manufactured by Toshiba Machine Co., Ltd.) and melt-kneaded at a barrel average heating temperature of 240°C. After that, the temperature is lowered to 220° C., and the phosphor-containing resin discharged is extruded from a φ1.8 mm orifice hole at a linear velocity of 28 m/min, and the discharged phosphor-containing resin is dipped in cold water. Manufactured by Imoto Manufacturing Co., Ltd.), and draw it at a linear velocity of 30 m/min, which makes the draw ratio 1.1 times, to obtain a linear shape with an average diameter of 1.75 mm, and further heat it in a vacuum furnace at 70° C. for 12 hours. , A phosphor-containing thermoplastic resin filament was obtained. The ratio (L/D) of the effective screw length L to the melting screw diameter D in this extrusion molding was 29.

The obtained phosphor-containing thermoplastic resin filament had a large variation in the diameter of each part, and a continuous molded body of 10 m or more could not be obtained. In addition, the number of minute irregularly shaped portions (fish eyes) due to defective melting was about 1 per 15 m.

[Example 1]
Using the filament obtained in Experimental Example 1, a 3D printer of the FDM method Ninjabot series NJB-300W (manufactured by Mitoyo Kogyo Co., Ltd.) and a molding nozzle of φ0.25 mm was applied, and as shown in FIGS. Three types of ring cap-shaped wavelength conversion members were produced. In addition, slicing software by Simplicity 3D was used for molding.

FIG. 1 is a diagram showing an example of the wavelength conversion member of the present invention, (A) is a perspective view, and (B) is a sectional view. The inner surface of the wavelength conversion member (No. 1) shown in FIG. 1 is only a circular ring-shaped flat surface (top surface), an inner peripheral surface (side surface) that is a truncated cone peripheral surface, and an outer surface (side surface) that is a circumferential surface. And a top surface and a side surface are joined via a tangent line to form a polyhedral discontinuous surface. Table 1 shows the size of each part of a to f shown in the figure. The inner circumference of the inner surface was φ29 mm, and the height from the LED to the upper end was 8.3 mm.

FIG. 2 is a diagram showing an example of the wavelength conversion member of the present invention, (A) is a perspective view, and (B) is a sectional view. The inner surface of the wavelength conversion member (No. 2) shown in FIG. 2 has a dodecagonal ring-shaped flat surface (top surface), an inner peripheral surface (side surface) that is a 12-sided truncated pyramid peripheral surface, and an outer surface that is a 12-sided prism peripheral surface ( Side surface), and the top surface and the side surface are joined via a tangent line to form a polyhedral discontinuous surface. Table 1 shows the size of each part of a to f shown in the figure. The outer peripheral size of the inner surface was 46 mm in maximum outer diameter, and the height from the LED to the upper end was 5 mm.

FIG. 3 is a diagram showing an example of the wavelength conversion member of the present invention, (A) is a perspective view, and (B) is a sectional view. The inner surface of the wavelength conversion member (No. 3) shown in FIG. 3 is composed only of a circular ring-shaped flat surface (top surface), an inner peripheral surface (side surface) that is a cylindrical peripheral surface, and an outer surface (side surface). And the side surface are joined to each other via a tangent line to form a polyhedral discontinuous surface. Table 1 shows the size of each part of a to f shown in the figure. The outer peripheral size of the inner surface was φ46 mm, and the height from the LED to the upper end was 6.3 mm.

FIG. 4 is an exploded perspective view showing an example of the remote phosphor type LED light emitting device of the present invention manufactured by using the wavelength conversion member (No. 1). As shown in FIG. 4, 12 LEDs 22 (PK2N blue (produced by ProLight Opto Technology, peak wavelength 453 nm) on a white-painted aluminum substrate 21 are connected in series on a circumference of φ38 mm at equal intervals. The wavelength conversion member 1 is disposed so that this LED array is located between the inner and outer peripheral surfaces on the bottom side of the wavelength conversion member 1 to form a remote phosphor type LED light emitting device 10. In this case, The height from the surface of the aluminum substrate to the upper end of the LED is 1.7 mm, and the optical characteristics of the LED light emitting device are measured by measuring the total luminous flux by applying a voltage of 3 V and a current of 200 mA with a stabilized power supply to the LED. The system HM-9100B (manufactured by Otsuka Electronics Co., Ltd.) was evaluated and the color variation was visually evaluated.The results are shown in Table 1. The color temperature of light emitted from the three types of LED light emitting devices is 4500. .About.5000 K, and the average color rendering index Ra was in the range of 91 to 93.

From the evaluation results of the optical characteristics, the wavelength conversion member manufactured using the phosphor-containing thermoplastic resin filament of the present invention has a high luminous efficiency, a small variation in chromaticity and color temperature, and a remote phosphor having high luminous characteristics. It can be seen that a mold type LED light emitting device was obtained.

1 Wavelength Conversion Member 10 Remote Phosphor Type LED Light Emitting Device 21 Substrate 22 LED

Claims (3)

A raw material filament for converting a wavelength of light emitted from an LED to produce a wavelength conversion member containing a phosphor that emits light of a wavelength different from the wavelength by a 3D printer by a melt lamination method, and particles. The above-mentioned fluorescent substance is dispersed in a thermoplastic resin at a concentration of 30% by mass or less,
The phosphor is A ₂ (M _1-x , Mn _x )F ₆ (wherein A is selected from Li, Na, K, Rb and Cs, and contains at least Na and/or K. At least one alkali metal, M is at least one tetravalent element selected from Si, Ti, Zr, Hf, Ge and Sn, and x is a positive number in the range of 0.001 to 0.3. A) containing a manganese-activated double-fluoride phosphor represented by
The phosphor-containing thermoplastic resin filament, wherein the thermoplastic resin is selected from an olefin resin, a cyclic polyolefin resin, an acrylic resin, a styrene resin, and an acrylimide resin. The manganese-activated double fluoride phosphor is represented by K ₂ (Si _1-x , Mn _x )F ₆ (where x is a positive number in the range of 0.001 to 0.3). The phosphor-containing thermoplastic resin filament according to claim 1, which is an activated potassium fluorosilicate phosphor. The phosphor-containing thermoplastic resin filament according to claim 1 or 2, wherein the thermoplastic resin is selected from acrylic resin, polystyrene, styrene copolymer, polyethylene, polypropylene and ethylene-propylene copolymer.

Images