CN105637660A - Laminated article and method for manufacturing light-emitting device using same - Google Patents

Abstract

An object of the present invention is to provide a laminate in which a phosphor sheet can be formed with a uniform thickness on the upper surface and side surfaces of an LED chip with good followability. Another object of the present invention is to provide a method of manufacturing a light-emitting device in which the upper surface and side surfaces of an LED chip are coated with a phosphor sheet by a method with high productivity using the laminate. The laminate includes a support substrate and a phosphor sheet, the phosphor sheet contains a phosphor and a resin, wherein the elongation at break at 23° C. of the support substrate obtained by a tensile test is 200% or more, and the Young's modulus at 23° C. of the support substrate is 600 MPa or less.

Description

Laminated body and method of manufacturing light-emitting device using same

technical field

The present invention relates to a laminate including a phosphor sheet containing a phosphor and a resin. More specifically, it relates to a laminate including a phosphor sheet for converting the wavelength of light emitted from the upper surface and side surfaces of an LED chip.

Background technique

As far as light-emitting diodes (LEDs, Light Emitting Diodes) are concerned, in the context of their significantly improved luminous efficiency, they are characterized by low power consumption, long life, and design. The automotive field such as headlights, and in the field of general lighting, its market is also rapidly expanding.

LEDs are classified into a lateral type, a vertical type, and a flip-chip type according to their mounting mode. Flip-chip type LEDs are attracting attention because they can increase brightness and have excellent heat dissipation. However, for flip-chip LEDs, there is a problem that the thickness of the phosphor layer cannot be made uniform between the upper surface and the side surface of the chip in the packaging performed by the conventional dispensing method, resulting in The orientation of the luminous color is uneven.

In order to solve this problem, techniques have been proposed in which a phosphor sheet, which is a phosphor-containing sheet, is adhered uniformly around the chip with good followability (see, for example, Patent Documents 1 and 2). Patent Document 1 is a method of affixing a phosphor sheet to the side surface of the LED chip using a pressing member formed with a concave portion slightly larger than the LED chip. In addition, Patent Document 2 is a method of placing a laminate including a support base and a phosphor sheet on an LED chip, and performing a first-stage pasting in which a diaphragm (diaphragm) is used to pressurize the laminate in a vacuum state. After that, the supporting substrate is removed, and the phosphor sheet is bonded to the side surface of the LED chip through a second-stage bonding process by non-contact pressure.

Patent Document 1: Japanese Patent Laid-Open No. 2011-138831

Patent Document 2: International Publication No. 2012/023119

Contents of the invention

However, the method of Patent Document 1 is economical because it is necessary to newly manufacture a mold as a pressurizing member every time the type of LED is changed. In addition, since the pressing member is brought into contact with the phosphor sheet and pressed, there are problems such as damage to the sheet, contamination of the pressing member, and poor productivity.

In addition, in the method of Patent Document 2, when only the diaphragm pressurization step of the first stage is used, the phosphor sheet cannot follow the side surface of the chip due to insufficient flexibility of the support base material. Therefore, after returning to atmospheric pressure and removing the support base The non-contact pressurization process of the second stage is performed after the material, which is problematic from the viewpoint of productivity.

An object of the present invention is to provide a laminate in which a phosphor sheet can be formed with a uniform film thickness with good followability on the upper surface and side surfaces of the LED chip. In addition, there is provided a method of manufacturing a light-emitting device in which the upper surface and side surfaces of an LED chip are covered with a phosphor sheet by a method with high productivity using the laminate.

The present invention is as follows.

[1] A laminate comprising a support substrate and a phosphor sheet containing a phosphor and a resin, wherein the temperature of the support substrate at 23°C obtained by a tensile test is: The elongation at break is 200% or more, and the Young's modulus at 23° C. of the support substrate is 600 MPa or less.

[2] The laminate according to [1], wherein the Young's modulus at 23° C. of the support base is 400 MPa or less.

[3] The laminate according to [1], wherein the Young's modulus at 23° C. of the support base is 100 MPa or less.

[4] The laminate according to any one of [1] to [3], wherein the supporting substrate is polyvinyl chloride or polyurethane.

[5] A method of manufacturing a light-emitting device, comprising the step (coating step) of covering the light-emitting surface of an LED chip bonded to a substrate with the laminate described in any one of [1] to [4]. The phosphor sheet is coated.

[6] A method of manufacturing a light-emitting device, comprising the step (coating step) of laminating the upper surface and side surfaces of an LED chip bonded to a substrate with the method described in any one of [1] to [4]. The bulk phosphor sheet is coated.

[7] The method of manufacturing a light-emitting device according to [5] or [6], wherein the LED chip and the phosphor sheet are in contact with the upper surface of the LED chip from the upper surface of the LED chip to the upper surface of the LED chip. The distance a [μm] from the outer surface of the phosphor sheet and the distance b [μm] from the side surface of the LED chip to the outer surface of the phosphor sheet in the portion where the LED chip and the phosphor sheet are in contact with the side surface of the LED chip ] satisfies the relationship of 1.00<a/b<1.20.

[8] The method for producing a light-emitting device according to [5] or [6], wherein in the step of coating with the phosphor sheet of the laminate described in any one of [1] to [4] ( In the covering step), the distance a [μm] from the upper surface of the LED chip to the outer surface of the phosphor sheet in the portion where the LED chip and the phosphor sheet are in contact with the upper surface of the LED chip and the The distance b [μm] from the side surface of the LED chip to the outer surface of the phosphor sheet in the portion where the LED chip and the phosphor sheet are in contact with the side surface of the LED chip satisfies the relationship of 1.00<a/b<1.20.

The effect of the invention

According to the present invention, the phosphor sheet can be adhered to the upper light emitting surface and the side light emitting surface of the LED chip with good followability. And thus, it is possible to provide a light-emitting device that does not have the problem of unevenness in the direction of the light-emitting color.

Description of drawings

Fig. 1 is a schematic diagram of a laminate of the present invention.

Fig. 2 is a schematic diagram of a laminate of the present invention with an adhesive.

Fig. 3 is an example of a method of manufacturing a light-emitting device using the laminate of the present invention.

4 is a schematic cross-sectional view and a top view of a light-emitting device covered with a phosphor sheet.

detailed description

The laminated body of this invention is shown in FIG. 1. The laminated body 1 of the present invention includes a supporting base material 2 and a fluorescent material sheet 3 containing a fluorescent material and a resin, and the supporting base material has an elongation at break of 200% or more in a tensile test at 23° C., and Young's modulus is 600 MPa or less.

That is, the laminate of the present invention is a laminate comprising a support substrate and a phosphor sheet containing a phosphor and a resin, wherein the temperature of the support substrate at 23° C. obtained by a tensile test is The elongation at break at 200% or more, and the Young's modulus at 23° C. of the support substrate is 600 MPa or less.

<Phosphor sheet>

The phosphor sheet is not particularly limited as long as it mainly contains resin and phosphor, and various phosphor sheets can be used. Other ingredients may also be included as needed.

(Physical properties of phosphor sheet)

The phosphor sheet preferably has high elasticity around room temperature from the viewpoint of storage properties, transport properties, and processability. On the other hand, from the viewpoint of deforming so as to follow the LED chip and bonding, it is preferable that the elasticity is lowered under certain conditions, and flexibility and adhesiveness (adhesiveness) are exhibited. From the above viewpoint, it is preferable that the present phosphor sheet is softened by heating at 60° C. or higher to exhibit adhesiveness.

The storage modulus of the phosphor sheet is preferably 0.1 MPa or more at 25°C and less than 0.1 MPa at 100°C, more preferably 0.5 MPa or more at 25°C and less than 0.05 MPa at 100°C.

The storage modulus mentioned here is the storage modulus at the time of dynamic viscoelasticity measurement. Dynamic viscoelasticity means that when a shear strain (shearstrain) is applied to a material at a certain sinusoidal frequency, the shear stress exhibited when it reaches a steady state is decomposed into a component (elastic component) whose phase is consistent with the strain, and a component whose phase is consistent with the strain. It is a method of analyzing the dynamic mechanical properties of materials by using components with a strain difference of 90° (viscous components). Here, the value obtained by dividing the stress component whose phase coincides with the shear strain by the shear strain is the storage modulus G'. Since it represents the deformation and follow-up of the material with respect to the dynamic strain at each temperature, it is related to the material's Processability and adhesiveness are closely related.

In the case of the phosphor sheet in the present invention, by having a storage modulus of 0.1 MPa or more at 25° C., even against rapid shear stress such as cutting with a cutting tool at room temperature (25° C.), The sheet can be cut without deformation around it, so processability with high dimensional accuracy can be obtained. The upper limit of the storage modulus at room temperature is not particularly limited as long as it satisfies the object of the present invention, but it is preferably 1 GPa or less in consideration of the need to reduce stress and strain after bonding with LED elements. In addition, by reducing the storage modulus at 100°C to less than 0.1 MPa, the phosphor sheet deforms rapidly and follows the shape of the surface of the LED chip when heat-attached at 60°C to 150°C, thereby obtaining high adhesive force. . If it is a phosphor sheet that can obtain a storage modulus of less than 0.1MPa at 100°C, the storage modulus will decrease as the temperature rises from room temperature, and even if it is less than 100°C, the adhesiveness will change as the temperature rises. However, in order to obtain practical adhesiveness, it is preferably 60° C. or higher. In addition, when the above-mentioned fluorescent substance sheet is heated at a temperature higher than 100°C, the decrease in the storage modulus progresses and the adhesiveness becomes better, but at a temperature higher than 150°C, the stress relaxation is insufficient, and the resin The curing is fast, and it is easy to crack and peel off. Therefore, a suitable temperature for heating and pasting is 60°C to 150°C, more preferably 60°C to 120°C. The lower limit of the storage modulus at 100°C is not particularly limited as long as it satisfies the purpose of the present invention. However, if the fluidity is too high when heat-attached to the LED element, it will not be possible to keep passing through cutting and opening before attaching. The shape obtained by processing is preferably 0.001 MPa or more.

As the phosphor sheet, as long as the above-mentioned storage modulus can be obtained, the resin contained therein may be an uncured or semi-cured resin, but when considering the handling and storage properties of the sheet as described below, the The resin contained is preferably a cured resin. When the resin is in an uncured or semi-cured state, a curing reaction may occur at room temperature during storage of the phosphor sheet, and the storage modulus may not be within an appropriate range. In order to prevent the above, it is desirable that the resin is cured, or stored at room temperature for a long time of about 1 month, so that the curing proceeds to such an extent that the storage modulus does not change.

(resin)

Any resin may be used as long as the resin contained in the phosphor sheet of the present invention can uniformly disperse the phosphor inside and form a sheet.

Specifically, silicone resin, epoxy resin, polyarylate resin (polyarylate resin), PET modified polyarylate resin, polycarbonate resin, cyclic olefin, polyethylene terephthalate resin , Polymethyl methacrylate resin, polypropylene resin, modified acrylic resin, polystyrene resin and acrylonitrile-styrene copolymer resin, etc. Here, PET is polyethylene terephthalate. In the present invention, silicone resins and epoxy resins are preferably used from the viewpoint of transparency. Furthermore, it is particularly preferable to use a silicone resin from the viewpoint of heat resistance.

As the silicone resin used in the present invention, curable silicone rubber is preferable. Either one-component type or two-component type (three-component type) can be used. Among curable silicone rubbers, there are dealcoholized type, deoximated type, deacetic acid type, and dehydroxylamine type, etc., as the type in which the condensation reaction is caused by moisture in the air or a catalyst. In addition, there is an addition reaction type as a type in which a hydrosilylation reaction is induced by a catalyst. Any of the types of curable silicone rubbers described above may be used. In particular, an addition reaction type silicone rubber is more preferable because it does not generate by-products accompanying the curing reaction, has little cure shrinkage, and is easy to accelerate curing by heating.

The addition reaction type silicone rubber can be formed, for example, by subjecting a compound containing an alkenyl group bonded to a silicon atom to a compound having a hydrogen atom bonded to a silicon atom to undergo a hydrosilylation reaction. Examples of such materials include vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, propenyltrimethoxysilane, norbornenyltrimethoxysilane, octane Compounds containing alkenyl groups bonded to silicon atoms, such as alkenyltrimethoxysilane, and polymethylhydrogenpolysiloxane, polydimethylsiloxane-CO-polymethylhydrogensiloxane, A material obtained by hydrosilylation of a compound having a hydrogen atom bonded to a silicon atom, such as polyethylhydrogensiloxane and polymethylhydrogensiloxane-CO-polymethylphenylsiloxane. In addition, other than the above-mentioned materials, for example, known substances described in JP 2010-159411 A can also be used.

By appropriately designing these resins so as to control the storage modulus at room temperature (25° C.) and the storage modulus at high temperature (100° C.), resins useful for the practice of the present invention can be obtained.

In addition, as a commercially available material, a material having an appropriate storage modulus may be selected from common silicone sealing materials for LEDs and used. Specific examples include OE-6630A/B and OE-6520A/B manufactured by Toray Dow Corning Corporation.

(phosphor)

The phosphor absorbs blue light, violet light, and ultraviolet light emitted from the LED chip, converts the wavelength, and emits light of red, orange, yellow, green, and blue wavelengths different from the light of the LED chip. As a result, part of the light emitted from the LED chip and part of the light emitted from the phosphor are mixed to obtain a multi-color LED including white. Specifically, a single LED chip can emit white light by optically combining a blue LED and a phosphor (which emits a yellow light emission color by light from the LED).

Among the above-mentioned phosphors, there are various types of phosphors such as phosphors emitting green light, phosphors emitting blue light, phosphors emitting yellow light, and phosphors emitting red light. Specific examples of phosphors used in the present invention include known phosphors such as organic phosphors, inorganic phosphors, fluorescent pigments, and fluorescent dyes. Examples of organic phosphors include allylsulfoamide-melamine-formaldehyde co-condensation dyes, perylene-based phosphors, and the like. From the viewpoint of long-term use, it is preferable to use a perylene-based phosphor. An inorganic fluorescent substance is mentioned as a fluorescent substance suitable especially for this invention. The inorganic phosphor used in the present invention will be described below.

Examples of phosphors that emit green light include SrAl ₂ O ₄ : Eu, Y ₂ SiO ₅ : Ce, Tb, MgAl ₁₁ O ₁₉ : Ce, Tb, Sr ₇ Al ₁₂ O ₂₅ : Eu, (Mg, Ca, Sr , Ba at least one or more) Ga ₂ S ₄ : Eu and the like.

Examples of phosphors that emit blue light include Sr ₅ (PO ₄ ) ₃ Cl:Eu, (SrCaBa) ₅ (PO ₄ ) ₃ Cl:Eu, (BaCa) ₅ (PO ₄ ) ₃ Cl:Eu, (Mg, At least one of Ca, Sr, Ba) ₂ B ₅ O ₉ Cl: Eu, Mn, (at least one of Mg, Ca, Sr, Ba) (PO ₄ ) ₆ Cl ₂ : Eu, Mn, etc. .

As phosphors emitting green to yellow light, there are yttrium-aluminum oxide phosphors activated with at least cerium, yttrium-gadolinium-aluminum oxide phosphors activated with at least cerium, and yttrium-aluminum oxides activated with at least cerium. Garnet oxide phosphors, yttrium-gallium-aluminum oxide phosphors activated with at least cerium (so-called YAG-based phosphors). Specifically, Ln ₃ M ₅ O ₁₂ : R (Ln is at least one selected from Y, Gd, and La. M includes at least one of Al and Ca. R is a lanthanide.), ( Y _1-x Ga _x ) ₃ (Al _1-y Ga _y ) ₅ O ₁₂ : R (R is at least one selected from Ce, Tb, Pr, Sm, Eu, Dy, Ho. 0<Rx< 0.5, 0<y<0.5.).

Examples of phosphors that emit red light include Y ₂ O ₂ S:Eu, La ₂ O ₂ S:Eu, Y ₂ O ₃ :Eu, Gd ₂ O ₂ S:Eu, and the like.

In addition, examples of phosphors that emit light corresponding to currently mainstream blue LEDs include Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, (Y, Gd) ₃ Al ₅ O ₁₂ : Ce, Lu ₃ Al ₅ O ₁₂ : Ce, Y ₃ Al ₅ O ₁₂ : YAG-based phosphors such as Ce, Tb ₃ Al ₅ O ₁₂ : TAG-based phosphors such as Ce, (Ba, Sr) ₂ SiO ₄ : Eu-based phosphors or Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce-based phosphor, (Sr, Ba, Mg) ₂ SiO ₄ : Silicate-based phosphor such as Eu, (Ca, Sr) ₂ Si ₅ N ₈ : Eu, (Ca, Sr)AlSiN ₃ : Eu, CaSiAlN ₃ : Nitride-based phosphors such as Eu, Cax(Si, Al) ₁₂ (O, N) ₁₆ : Nitride-based phosphors such as Eu, and further, (Ba, Sr, Ca)Si ₂ O ₂ N ₂ : Eu-based phosphor, Ca ₈ MgSi ₄ O ₁₆ Cl ₂ : Eu-based phosphor, SrAl ₂ O ₄ : Eu, Sr ₄ Al ₁₄ O ₂₅ : Eu phosphor.

Among them, YAG-based phosphors, TAG-based phosphors, and silicate-based phosphors are preferably used from the viewpoint of luminous efficiency, brightness, and the like.

In addition to those described above, known phosphors can be used depending on applications and target emission colors.

The particle size of the phosphor is not particularly limited, but D50 is preferably 0.05 μm or more, more preferably 3 μm or more. In addition, D50 is preferably 30 μm or less. Here, D50 refers to the particle diameter at which the cumulative percent passing from the small particle diameter side is 50% in the volume-based particle size distribution measured by the laser diffraction scattering particle size distribution measurement method. When D50 is in the above-mentioned range, the dispersibility of the phosphor in the phosphor sheet is favorable, and stable light emission can be obtained.

In the present invention, the content of the phosphor is not particularly limited, but from the viewpoint of improving the wavelength conversion efficiency of light emitted from the LED chip, it is preferably at least 30% by weight of the entire phosphor sheet, and more preferably at least 40% by weight. . The upper limit of the phosphor content is not particularly specified, but it is preferably 95% by weight or less of the phosphor sheet as a whole, more preferably 90% by weight or less, and even more preferably It is 85% by weight or less, particularly preferably 80% by weight or less.

The phosphor sheet of the present invention is particularly preferably used for surface coating of LED chips. In this case, by setting the content of the phosphor in the phosphor sheet within the above-mentioned range, an LED light-emitting device exhibiting excellent performance can be obtained.

(polysiloxane microparticles)

The phosphor sheet of the present invention may contain polysiloxane fine particles in order to improve the fluidity of the resin composition used for producing the phosphor sheet and to improve applicability. The polysiloxane microparticles contained are preferably microparticles made of silicone resin and/or silicone rubber. Particular preference is given to polysiloxane microparticles obtained by combining organotrialkoxysilanes or organodialkoxysilanes, organotriacetoxysilanes, organodiacetoxysilanes, organotrioxime silanes, organic Organosilanes such as dioximesilane are hydrolyzed followed by condensation.

Examples of organotrialkoxysilanes include methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltriisopropoxysilane, methyltri-n-butoxysilane methylsilane, methyltriisobutoxysilane, methyltri-sec-butoxysilane, methyltri-tert-butoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, isopropyltrimethoxysilane butylsilane, n-butyltributoxysilane, isobutyltributoxysilane, sec-butyltrimethoxysilane, tert-butyltributoxysilane, N-β-(aminoethyl)-γ- Aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane and the like.

Examples of organodialkoxysilanes include dimethyldimethoxysilane, dimethyldiethoxysilane, methylethyldimethoxysilane, methylethyldiethoxysilane, Ethyldiethoxysilane, diethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxy N-(2-aminoethyl)-3-aminoisobutylmethyldimethoxysilane, N-ethylaminoisobutylmethyldiethoxysilane, (phenylaminomethyl)methyldimethylsilane Oxysilane, Vinylmethyldiethoxysilane, etc.

As organotriacetoxysilane, methyltriacetoxysilane, ethyltriacetoxysilane, vinyltriacetoxysilane, etc. are mentioned.

Examples of organodiacetoxysilane include dimethyldiacetoxysilane, methylethyldiacetoxysilane, vinylmethyldiacetoxysilane, vinylethyldiacetoxysilane, etc. .

Examples of organotrixime silanes include methyltrimethylethylketoxime silane and vinyltrimethylethylketoxime silane, and examples of organodioxime silanes include methylethyldimethylethylketone oxime silane etc.

Specifically, the above-mentioned particles can be obtained by the following methods: the method reported in Japanese Patent Laid-Open No. 63-77940, the method reported in Japanese Patent Laid-Open No. 6-248081, the method reported in Japanese Patent Laid-Open No. 2003-342370 The reported method, the method reported in Japanese Patent Application Laid-Open No. 4-88022, and the like. In addition, the following methods are known: organosilanes such as organotrialkoxysilane or organodialkoxysilane, organotriacetoxysilane, organodiacetoxysilane, organotrioximine silane, organodioxime silane and/or A method in which a particle is obtained by adding its partial hydrolyzate to an alkaline aqueous solution to hydrolyze and condense it; adding an organosilane and/or its partial hydrolyzate to water or an acidic solution to obtain the organosilane and/or its part A method in which particles are obtained by adding a base to carry out a condensation reaction after the hydrolyzate is partially hydrolyzed; the organic silane and/or its hydrolyzate is the upper layer, and the base or the mixture of the base and the organic solvent is the lower layer, and at the interface of these layers The particles used in the present invention can be obtained by any of the methods of obtaining particles by hydrolyzing and polycondensing the organosilane and/or its hydrolyzate.

Among them, when organosilane and/or its partial hydrolyzate are hydrolyzed and condensed to produce spherical polysiloxane microparticles, it is preferably obtained by adding a polymer dispersant such as a water-soluble polymer or a surfactant to the reaction solution. Polysiloxane microparticles. As long as the water-soluble polymer functions as a protective colloid in a solvent, any of synthetic polymers and natural polymers can be used. Specifically, water-soluble polymers such as polyvinyl alcohol and polyvinylpyrrolidone are mentioned. The surfactant should just function as a protective colloid by having a hydrophilic part and a hydrophobic part in the molecule. Specifically, anionic surfactants such as sodium dodecylbenzenesulfonate, ammonium dodecylbenzenesulfonate, sodium lauryl sulfate, ammonium lauryl sulfate, sodium polyoxyethylene alkyl ether sulfate, Cationic surfactants such as lauryl trimethyl ammonium chloride and stearyl trimethyl ammonium chloride; polyoxyethylene alkyl ether, polyoxyethylene distyrenated phenyl ether, polyoxyalkylene alkenes Ether-based or ester-based nonionic surfactants such as base ethers and sorbitan monoalkyl esters; polyether-modified polydimethylsiloxane, polyester-modified polydimethylsiloxane, aromatic Polysiloxane-based surfactants such as alkyl-modified polyalkylsiloxanes; and fluorine-based surfactants such as perfluoroalkyl-containing oligomers; acrylic-based surfactants. As the method of adding the dispersant, the method of adding in advance to the initial reaction liquid, the method of adding the organotrialkoxysilane and/or its partial hydrolyzate at the same time, and the method of hydrolyzing the organotrialkoxysilane and/or its part The method of adding after the hydrolysis and partial condensation of the product can also be selected from any one of these methods. The added amount of the dispersant is preferably in the range of 5×10 ⁻⁷ to 0.1 parts by weight relative to 1 part by weight of the reaction liquid. When it is less than the lower limit, the particles tend to aggregate to form lumps. Moreover, when it exceeds an upper limit, the dispersing agent residue in a particle will increase and it will become a cause of coloring.

The above polysiloxane particles may be modified with a surface modifying agent for the purpose of controlling dispersibility to matrix components, wettability, and the like. The surface modifying agent may be modified by physical adsorption or modified by chemical reaction, specifically, silane coupling agent, thiol coupling agent, titanate coupling agent, etc. Modification with a silane coupling agent is particularly preferable in terms of strong heat resistance and no inhibition of curing.

The organic substituent contained in the polysiloxane microparticles is preferably a methyl group or a phenyl group, and the refractive index of the polysiloxane microparticles can be adjusted by the content of these substituents. In order not to reduce the brightness of the LED light-emitting device and to use it without scattering the light passing through the silicone resin, which is the binder resin, it is preferable that the refractive index d1 of the polysiloxane microparticles and the diluent The refractive index difference of the refractive index d2 of the components other than the polysiloxane fine particles and the phosphor is small. The difference between the refractive index d1 of the silicone fine particles and the refractive index d2 of components other than the silicone fine particles and the phosphor is preferably less than 0.10, more preferably 0.03 or less. By controlling the refractive index to the above range, the reflection and scattering at the interface between the polysiloxane microparticles and the silicone composition can be reduced, and high transparency and light transmittance can be obtained without reducing the brightness of the LED light emitting device.

Regarding the determination of the refractive index, the total reflection method can use Abbe refractometer, Pulfrich refractometer, liquid immersion refractometer, liquid immersion method, minimum deflection angle method, etc., but the silicone combination The Abbe refractometer is useful for the measurement of the refractive index of objects, and the liquid immersion method is useful for the measurement of the refractive index of polysiloxane particles.

In addition, as a means for controlling the above-mentioned difference in refractive index, it is possible to adjust by changing the molar ratio of the raw materials constituting the polysiloxane fine particles. That is, for example, by adjusting the mixing ratio of methyltrialkoxysilane and phenyltrialkoxysilane as raw materials and increasing the composition ratio of methyl groups, a low refractive index close to 1.4 can be achieved. Conversely, by increasing The composition ratio of the phenyl group enables a relatively high refractive index.

In the present invention, the average particle diameter of the polysiloxane fine particles is represented by a median diameter (D50), and the lower limit of the average particle diameter is preferably 0.01 μm or more, more preferably 0.05 μm or more. In addition, the upper limit is preferably 2.0 μm or less, more preferably 1.0 μm or less. When the average particle diameter is 0.01 μm or more, it is easy to produce particles with a controlled particle diameter, and by making the average particle diameter 2.0 μm or less, the optical characteristics of the phosphor sheet become favorable. Moreover, the fluidity improvement effect of the resin liquid for fluorescent substance sheet manufacture can fully be acquired by making an average particle diameter into 0.01 micrometer or more and 2.0 micrometer or less. In addition, monodisperse and spherical particles are preferably used. In the present invention, the median diameter (D50) and particle size distribution of the polysiloxane fine particles contained in the phosphor sheet can be measured by SEM (scanning electron microscope) observation of a cross section of the sheet. The particle size distribution was obtained by image processing the measurement image obtained by SEM, and in the particle size distribution thus obtained, the particle size at which the cumulative pass rate from the small particle size side was 50% was defined as the median particle size D50. Find out. At this time, as in the case of the phosphor particles, the average particle diameter of the polysiloxane microparticles obtained from the cross-sectional SEM image of the phosphor sheet is theoretically the true average particle diameter compared with the true average particle diameter. The average particle diameter of the polysiloxane microparticles in the present invention is defined as a value obtained by the above-mentioned measuring method.

The lower limit of the content of the polysiloxane fine particles is preferably 1 part by weight or more, more preferably 2 parts by weight or more, relative to 100 parts by weight of the silicone resin. In addition, the upper limit is preferably 20 parts by weight or less, more preferably 10 parts by weight or less. By containing more than 1 part by weight of polysiloxane fine particles, a particularly good phosphor dispersion stabilization effect can be obtained. On the other hand, by containing 20 parts by weight or less of polysiloxane fine particles, it is possible to prevent the combination of silicone The viscosity of the substance rises excessively.

(other ingredients)

The phosphor sheet of the present invention may further contain an inorganic fine particle filler in order to impart effects such as viscosity adjustment, light diffusion, and coating property improvement. Examples of fillers for the above-mentioned use include silica, alumina, titania, zirconia, barium titanate, zinc oxide and the like.

In addition, in the present invention, in the silicone resin composition used for producing the phosphor sheet, as other components, in order to suppress curing at room temperature and prolong the shelf life, it is preferable to mix hydrosilanes such as acetylenealcohol or the like. chemical reaction blocker. In addition, as other additives, a leveling agent for stabilizing the coating film, an adhesion auxiliary agent such as a silane coupling agent as a modifier of the sheet surface, and the like may be added.

(film thickness)

The film thickness of the phosphor sheet of the present invention is determined by the phosphor content and desired optical properties. The phosphor content is limited from the viewpoint of handling as described above, so the film thickness is preferably 10 μm or more. On the other hand, the film thickness of the phosphor sheet is preferably 1000 μm or less, more preferably 200 μm or less, still more preferably 100 μm or less, from the viewpoint of improving the optical properties and heat dissipation of the phosphor sheet. By making the phosphor sheet have a film thickness of 1000 μm or less, light absorption and light scattering by the binder resin and the phosphor can be reduced, and thus an optically excellent phosphor sheet can be formed.

In addition, if the film thickness of the sheet varies, the amount of phosphor varies for each LED chip, and as a result, the emission spectrum (color temperature, luminance, chromaticity) varies. Therefore, the variation in film thickness of the sheet is preferably within ±5%, more preferably within ±3%.

The film thickness of the phosphor sheet in the present invention refers to the film thickness (average film thickness). Moreover, using the said average film thickness, the film thickness variation of a phosphor sheet was calculated based on the following mathematical formula. More specifically, the film thickness is measured using a micrometer such as a commercially available contact thickness meter under the measurement conditions of the method A method of measuring the thickness by mechanical scanning, and the calculated maximum value or minimum value and the average value of the film thickness are For the difference in film thickness, this value is divided by the average film thickness and expressed as a percentage, and the obtained value is the film thickness deviation B (%).

Film thickness deviation (%)={(maximum film thickness deviation value-average film thickness)/average film thickness}×100

Here, as the maximum film thickness deviation value, one of the maximum value or the minimum value of the film thickness, which has a larger difference from the average film thickness, is selected.

<Support base material>

The support substrate protects the easily deformable phosphor sheet, facilitates storage, transportation, and processing, and facilitates handling in the process of attaching LED chips to prevent adhesion and contamination to the press substrate.

(Physical properties of supporting substrate)

The support substrate has an elongation at break of 200% or more at 23°C and a Young's modulus of 600 MPa or less. When the elongation at break of the supporting base material is less than 200% or the Young's modulus exceeds 600 MPa, gaps are formed between the side surface and the phosphor sheet in the LED bonding process, resulting in poor followability. From the viewpoint of followability to the LED chip, the elongation at break is preferably 300% or more, and more preferably 500% or more. In addition, the Young's modulus is preferably 400 MPa or less, more preferably 100 MPa or less, even more preferably 10 MPa or less. The upper limit of the elongation at break is not particularly limited, but is preferably 1500% or less, more preferably 1000% or less, still more preferably 800% or less, particularly preferably 750% or less, from the viewpoint of ease of cutting. The lower limit of Young's modulus is not particularly limited, but it is preferably 0.1 MPa or more, more preferably 1 MPa or more, and still more preferably 1.6 MPa or more, from the viewpoint of protecting the phosphor sheet without deformation of the supporting substrate.

The elongation at break and the Young's modulus can be measured by a method based on ASTM-D882-12. As a specific measurement method, the test piece is stretched at a speed of 300 mm/min using a tensile testing machine in an environment maintained at a constant temperature. When the length of the test piece before the test is L ₀ and the length of the test piece after cutting (breaking) is L, the elongation at break was calculated by the following formula.

Elongation at break (%)=100×(LL ₀ )/L ₀ .

In addition, the Young's modulus can be obtained from the maximum elasticity of the test piece immediately before deformation, that is, the maximum inclination of the S-S curve obtained by plotting the elongation of the test piece and the load applied thereto. The number of measurements of elongation at break and Young's modulus was three times in order to improve accuracy, and the average value was calculated|required.

As described above, the sticking temperature of the phosphor sheet is preferably 60°C to 150°C, more preferably 60°C to 120°C. Therefore, as the thermal characteristics of the supporting base material, it is preferable that melting does not occur in this temperature range. From this viewpoint, the melting point of the support substrate is preferably 120°C or higher, more preferably 150°C or higher.

In addition, for the supporting base material, the peeling force of the supporting base material is preferably between In the range of 0.5 ~ 2.5N/20mm. The peeling force described here is a value obtained by an adhesiveness test method by a 90-degree tear in the adhesive tape/adhesive sheet method prescribed in JIS Z0237 (2009).

In general, the supporting base material preferably has an average surface roughness Ra of 1 μm or less from the viewpoint of uniformity of light emission, but surface processing such as embossing may be performed in order to increase the amount of emitted light.

(Material of supporting substrate)

Specific examples of the material of the supporting substrate include polyvinyl chloride, polyurethane, silicone, low-density polyethylene (LDPE), and polyvinyl acetal. Polyvinyl chloride has hard and soft properties depending on the amount of plasticizer added, and soft polyvinyl chloride is preferred. In addition, there are resins and rubbers in silicone, and silicone rubber excellent in stretchability is preferable. Among them, polyvinyl chloride, polyurethane, or silicone is preferable from the viewpoint of high elongation, low Young's modulus, thermal properties, adhesiveness, and peelability. It is more preferably polyvinyl chloride or polyurethane, particularly preferably soft polyvinyl chloride or polyurethane, most preferably polyurethane (polyurethane film).

For the film made of the above materials, elongation at break and Young's modulus can be controlled within the above preferred ranges by, for example, low density, non-stretching, increase in the monomer amount of the soft component, increase in plasticizer, etc. Inside.

(Film thickness of supporting substrate)

The film thickness of the supporting substrate is preferably 5 μm to 500 μm, more preferably 20 μm to 200 μm, and still more preferably 40 μm to 100 μm. In addition, the film thickness of the supporting base material preferably satisfies the following mathematical formula with respect to the film thickness of the phosphor sheet.

1/5≤(film thickness of support substrate/film thickness of phosphor sheet)≤3

When it is more than the lower limit, the supporting base material can acquire sufficient mechanical strength for protecting a fluorescent substance sheet. Moreover, when it is below an upper limit, sufficient followability with respect to an LED chip can be acquired in bonding of a fluorescent substance sheet. From this point of view, the lower limit of (film thickness of supporting substrate/film thickness of phosphor sheet) is more preferably 1/2 or more. In addition, the upper limit is more preferably 2 or less, and still more preferably 1 or less.

<Other components in the laminate>

The laminate of the present invention may also have an adhesive on the supporting substrate. Fig. 2 is an example of a laminate with an adhesive. In this case, the laminate 1 is formed so that the surface coated with the adhesive 4 is in contact with the phosphor sheet 3 , and the phosphor sheet 3 is fixed to the support base 2 via the adhesive 4 . From the viewpoint of holding the phosphor sheet on the support base, the adhesive force of the adhesive is preferably 0.1 N/20 mm or more. In addition, the adhesive force of the adhesive is preferably 1.0 N/20 mm or less from the viewpoint of peeling the support substrate after covering the LED chip with the phosphor sheet.

In addition, in the laminate of the present invention, for the purpose of protecting the surface of the phosphor sheet, a protective base material may be provided on the phosphor sheet. As the protective substrate, known metals, films, glass, ceramics, paper and the like can be used. Specifically, metal plates and foils such as aluminum (including aluminum alloys); cellulose acetate, polyethylene terephthalate (PET), polyethylene, polyester, polyamide, polyimide, etc.; Films of amine, polyphenylene sulfide, polystyrene, polypropylene, polycarbonate, aramid, fluororesin, etc.; processed paper such as resin-laminated paper, resin-coated paper, etc. It is preferable to perform peeling treatment on the surface of the protective substrate in advance so that the phosphor sheet does not adhere during storage. In addition, a high-strength substrate is preferable so that the phosphor sheet does not bend or have surface damage during storage or transportation. From the viewpoint of satisfying the above-mentioned required properties, a film or paper is preferable, and among them, a release-treated PET film or release paper is more preferable from the viewpoint of economy and handleability.

<Manufacturing method of laminated body>

The method for producing the laminate of the present invention may be any method capable of forming the laminate, and examples thereof include a direct coating method, a transfer method using an adhesive, and a thermal transfer method.

The direct coating method is a method in which the composition for producing a phosphor sheet is coated on a support substrate and then cured by heating. The details of the "phosphor sheet preparation composition" will be described later, but the "phosphor sheet preparation composition" is used as a coating liquid for phosphor sheet formation. The composition is a composition obtained by dispersing a phosphor in a resin.

The transfer method using an adhesive is a method in which the adhesive surface of a supporting base material having an adhesive is attached to a phosphor sheet produced on a second base material, and the phosphor sheet is removed from the The second substrate is transferred onto the support substrate.

The thermal transfer method is a method in which a phosphor sheet produced on a second base material is bonded to a support base material under heat and pressure, and the phosphor sheet is transferred from the second base material to the support base material. superior.

As a method for producing the laminate, from the viewpoint of producing a phosphor sheet with high film thickness accuracy, the transfer method and thermal transfer method using an adhesive are preferred. From the viewpoint of stability, thermal transfer method is more preferable.

Here, production of the phosphor sheet will be described. In addition, the following is an example, and the manufacturing method of a fluorescent substance sheet is not limited to this. First, as a coating liquid for phosphor sheet formation, a composition in which phosphor was dispersed in a resin (hereinafter referred to as "phosphor sheet preparation composition") was produced. For the purpose of suppressing sedimentation of the phosphor, polysiloxane fine particles may be added, and other additives such as inorganic fine particles, leveling agents, and adhesion aids may be added. In addition, when an addition reaction type silicone resin is used as the resin, a hydrosilylation reaction retarder may be added to prolong the pot life. In order to obtain appropriate fluidity, a solvent may be added to form a solution as necessary. The solvent is not particularly limited as long as it can adjust the viscosity of the resin in a fluid state. For example, toluene, methyl ethyl ketone, methyl isobutyl ketone, hexane, acetone, terpineol, etc. are mentioned.

After mixing these components according to the prescribed composition, they are uniformly mixed and dispersed by homogenizers, rotation/revolution type mixers, three-roll mills, ball mills, planetary ball mills, bead mills, and other mixers and kneaders to obtain phosphors. Composition for sheet production. After mixing and dispersing or during mixing and dispersing, it is also preferable to perform defoaming under vacuum or reduced pressure.

Next, the composition for phosphor sheet production is applied on the base material and dried. Coating can use reverse roll coater, blade coater, slit die coater, direct gravure coater, offset gravure coater, reverse roll Coater, blade coater, kiss coater, natural roll coater (natural roll coater), air knife coater, roll blade coater (roll blade coater), adjustable bar roll blade coating Machine (vari-barroll bladecoater), double stream coater (twostreamcoater), rod coater, wire bar coater (wirebarcoater), applicator (applicator), dip coater, curtain coater, spin coater machine, knife coater (knifecoater), etc. In order to obtain the film thickness uniformity of the phosphor sheet, it is preferable to perform coating with a slot die coater. In addition, the phosphor sheet of the present invention can also be produced using printing methods such as screen printing, gravure printing, and offset printing. When using the printing method, it is particularly preferable to use screen printing.

Drying and curing of the phosphor sheet can be carried out using a common heating device such as a hot air dryer or an infrared dryer. The heat curing conditions are usually 2 minutes to 3 hours at 80°C to 200°C, but it is preferable to heat at 80°C to 120°C for 30 minutes in order to obtain a so-called B-stage state that can be softened by heating and exhibit adhesiveness. ~2 hours.

In the case of using the second substrate (which is employed in the transfer method using an adhesive and the thermal transfer method), there is no particular limitation, and known metals, films, glass, ceramics, paper, etc. can be used . In order to produce a phosphor sheet with high film thickness accuracy, the elongation at break of the second base material at 23°C is preferably less than 200%, and the Young's modulus is greater than 600 MPa, especially the Young's modulus is more preferably 4000 MPa or more. In addition, it is preferably a base material with little deformation at a temperature of 150° C. or higher at which the curing reaction of the resin proceeds rapidly.

Specifically, aluminum (including aluminum alloy), zinc, copper, iron and other metal plates or foils, cellulose acetate, polyethylene terephthalate (PET), polyethylene, polyester, Films of plastics such as polyamide, polyimide, polyphenylene sulfide, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, aramid, paper laminated with the above plastics, or Paper coated with the plastic, paper laminated or vapor-deposited with the metal, plastic film laminated or vapor-deposited with the metal, and the like.

Among the above-mentioned substrates, resin films are preferable, and PET films or polyphenylene sulfide films are particularly preferable in view of the above-mentioned required properties and economical efficiency. In addition, when a high temperature of 200° C. or higher is required for curing the resin or attaching the phosphor sheet to the LED, a polyimide film is preferable from the viewpoint of heat resistance.

In addition, in order to facilitate the transfer of the phosphor sheet, it is preferable to perform a peeling treatment on the surface of the second base material in advance.

The thickness of the second base material is not particularly limited, but the lower limit is preferably 30 μm or more, more preferably 50 μm or more. In addition, the upper limit is preferably 5000 μm or less, more preferably 3000 μm or less.

In order not to mix air, the transfer from the second base material to the support base material with the adhesive is preferably performed using a laminator with rollers.

In addition, thermal transfer from the second base material to the support base material is preferably performed by a thermal laminator equipped with a heating mechanism and a pressurizing mechanism. Here, thermal transfer is preferably performed at 60° C. or higher from the viewpoint of softening the phosphor sheet and exhibiting adhesiveness. Moreover, it is preferable to carry out at 120 degreeC or less from a viewpoint of maintaining the B-stage state (that is, the semi-cured state) of a fluorescent substance sheet. In addition, from the viewpoint of maintaining the uniformity of film thickness, the pressing pressure is preferably 0.3 MPa or less, and the pressing time is preferably 30 seconds or less, more preferably 10 seconds or less.

<Manufacturing method of light-emitting device>

A method of manufacturing a light-emitting device using the laminate of the present invention will be described.

In the present invention, it is preferable to manufacture a light-emitting device by a manufacturing method having the step of coating the light-emitting surface of an LED chip bonded (mounted) on a substrate with the phosphor sheet of the laminate of the present invention. process (coating process).

In addition, when the light-emitting surface of the LED chip is the upper surface and the side surface of the LED chip, etc., it is preferable to manufacture the light-emitting device by a manufacturing method having the following steps of bonding (mounting) the LED chip on the substrate. A step of coating the upper surface and side surfaces of the laminate with the phosphor sheet of the present invention (coating step).

As described above, the light-emitting device using the laminated body of the present invention is preferably produced by bonding (mounting) the LED chip to the substrate, and then emitting light from the upper light-emitting surface and side portions of the LED chip using the laminated body of the present invention. The surface was covered with a phosphor sheet.

The substrate is a substance that fixes the LED chip and connects it to wiring. The substrate may be, for example, a base substrate, or may be a submount substrate. The material of the substrate is not particularly limited, and examples thereof include resins such as polyphthalamide (PPA), liquid crystal polymer, and silicone, aluminum nitride (AlN), aluminum oxide (Al ₂ O ₃ ), boron nitride ( BN) and other ceramics, aluminum and other metals.

A substrate on which an electrode pattern is formed with, for example, silver or the like is used. In addition, a heat release mechanism may also be provided.

As the LED chip, it is preferable to use an LED chip that emits blue light or ultraviolet light. As such an LED chip, a gallium nitride-based LED chip is particularly preferable.

The pattern of the LED chip can be any of a lateral type, a vertical type, and a flip-chip type, but the flip-chip type is particularly preferable from the viewpoint of high brightness and high heat dissipation. In the present invention, bonding (mounting) the LED chip to the substrate is preferably a state where the LED chip is electrically bonded to the substrate. The bonding (mounting) of a flip chip includes solder bonding, eutectic bonding, and conductive paste bonding.

A single LED chip may be bonded (mounted) to a substrate, or a plurality of LED chips may be bonded (mounted) to a substrate. In addition, individual packages may be coated with a phosphor sheet, or an article in which a plurality of packages are arrayed may be coated with a phosphor sheet collectively, and then singulated by dicing or the like.

The film thickness of the LED chip is not particularly limited, but it is preferably 500 μm or less, more preferably 300 μm or less, from the viewpoint of reducing the pressure applied to the phosphor sheet on the upper surface and corners of the LED chip and maintaining uniform film thickness. Preferably it is 200 μm or less.

In addition, the total film thickness of the LED chip and its connection with the substrate and the film thickness of the phosphor sheet preferably satisfy the following relational expression.

1≦(total film thickness of the LED chip and its connection with the substrate/film thickness of the phosphor sheet)≦10.

When it is more than the lower limit, it becomes easy to suppress the azimuth unevenness of the emission color. Moreover, when it is below an upper limit, it becomes easy to maintain the film thickness uniformity of a phosphor sheet. From this viewpoint, the lower limit is preferably 2 or more. In addition, the upper limit is preferably 5 or less, and more preferably 4 or less.

From the viewpoint of softening the phosphor sheet and exhibiting adhesiveness, it is preferable to perform the bonding of the laminate of the present invention to the LED chip under heating conditions. The heating temperature is preferably from 60°C to 150°C, more preferably from 60°C to 120°C, from the viewpoint of sufficiently softening the phosphor sheet and preventing rapid curing.

In addition, it is preferable to carry out the bonding of the laminate to the LED chip under pressure from the viewpoint of improving the followability to the side surface of the chip. The pressure is preferably 0.1 MPa to 0.3 MPa from the viewpoint that the phosphor sheet can be pressed against the side surface of the LED chip and the film thickness can be maintained.

Specific examples of pressurization methods include a method of pressing a flexible sheet by expanding it, a method of injecting gas such as air and pressing it in a non-contact manner, and pressing a mold made according to the shape of an LED chip. And the method of extruding, or the method of extruding with a roll. In addition, these methods can also be combined multiple types.

Furthermore, in order to prevent air from being mixed between the phosphor sheet, the LED chip, and the substrate, the bonding of the laminate to the LED chip is preferably performed under vacuum atmosphere conditions.

The device for attaching the LED chip using the laminate of the present invention is not particularly limited as long as it satisfies the above-mentioned conditions, but is preferably equipped with a pressing mechanism (in the A vacuum lamination device with a vacuum chamber attached to a platen (platen). As such a vacuum lamination apparatus, the apparatus described in Japanese Patent No. 3646042 is mentioned, for example.

An example of a method of manufacturing a light-emitting device using the vacuum lamination apparatus described above will be described with reference to FIG. 3 . This vacuum lamination apparatus consists of a press mechanism 11 (which includes an upper press plate 6, a flexible sheet 8, a closed space 9 surrounded by them, and an air injection/exhaust port 10), a lower press plate 7 with a heater, and a vacuum chamber. Chamber 5 (which has another air injection and discharge port 12) constitutes. The substrate 13 on which the LED chip 14 is bonded (mounted) is provided on the lower platen 7, and the laminate 1 including the supporting base material 2 and the phosphor sheet 3 is brought into contact with the surface of the LED chip through the phosphor sheet 3. The orientations of them coincide in turn (Fig. 3a). Next, from the air injection/discharge port 10 and the air injection/discharge port 12, the air is discharged (vacuumized) in the direction of the arrow indicated by the dotted line in FIG. The space 9 becomes a vacuum atmosphere (FIG. 3b). Next, while heating the lower platen 7 with a heater not shown, air is injected from the air injection/discharge port 10 in the direction of the arrow in FIG. The flexible sheet 8 expands to stick the laminate 1 on the LED chip 14 (FIG. 3c). Next, air is injected from the air injection/exhaust port 12 in the direction of the arrow in FIG. 3d, thereby injecting air into the vacuum chamber 5, returning to normal pressure (FIG. 3d), and taking out the light emitting device 15 (FIG. 3e). Finally, the support substrate 2 is removed from the laminated body 1 attached to the light-emitting device 15 ( FIG. 3 f ). As described above, it is preferable that the light-emitting device of the present invention finally has a configuration that does not include a support base material as shown in FIG. 3f. This is because the light-emitting device is often used or distributed in a configuration in which the support base is removed from the laminated body of the light-emitting device.

By using the laminate of the present invention as described above, the phosphor sheet can be coated on the LED chip by one-stage pressing, and a method for producing a light-emitting device with high productivity can be provided.

In addition, for example, this method can also be applied to the conventional two-stage extrusion method described in Patent Document 2, that is, a method in which contact extrusion by a flexible sheet and non-contact extrusion by air injection are continuously performed. Invented laminate.

Especially in the case of coating a plurality of LED chips arranged at intervals of 1000 μm or less on a substrate with a phosphor sheet, even if the two-stage extrusion method is used alone, sufficient adhesion accuracy (coating accuracy) may not be obtained. Propensity. However, even in such a case, coating can be performed with high precision by using the laminate of the present invention (using a supporting base material having a small Young's modulus) in addition to the two-stage extrusion method.

<light emitting device>

A light-emitting device obtained by using the laminate of the present invention will be described. 4 is a cross-sectional view of a light-emitting device (an example) in which an LED chip 14 bonded to a substrate 13 is covered with a phosphor sheet 3 via bumps 18 (such as gold bumps). Schematic diagram of the upper surface.

In the lower part of Fig. 4, a schematic view of the upper surface of the light emitting device is shown. Here, 16 denotes the covering portion on the upper surface and side surfaces of the LED chip, and 17 denotes the covering portion on the base material.

On the other hand, in the upper part of FIG. 4 , a cross section of the light emitting device is shown. The cross-sectional view shown in the upper part of FIG. 4 shows, as an example, a cross-section at the position of the dotted line II in the top view. The cross section of such a phosphor sheet-coated chip can be confirmed by making a cross section (exposing the cross section) using a mechanical grinding method, an ion milling method (including a cross section polishing method) or the like, and digitally Microscope (digital microscope), SEM (scanning electron microscope) method of observing the above-mentioned section; or method of non-destructively using X-ray CT scanning to observe without going through the section production process such as grinding.

A light-emitting device includes at least a substrate, an LED chip bonded (mounted) to the substrate, and a phosphor sheet that covers the light-emitting surface of the LED chip. Here, the light-emitting surface refers to a surface that emits light from the LED. Classifications with different light emitting surfaces include types that emit light from the top surface and side surfaces such as flip chip type and lateral type chip, and types that emit light only from the top surface such as vertical type. Furthermore, as an example, a type in which a side reflective layer of a flip chip is provided so that light is emitted only from the upper surface is also mentioned. Moreover, for the purpose of providing adhesiveness etc., a transparent resin may exist between a fluorescent substance sheet and the light emitting surface of LED. Here, examples of the transparent resin include thermosetting resins such as acrylic resins, epoxy resins, and silicone resins, among which silicone resins are most preferable from the viewpoint of heat resistance and light resistance.

Among the above, it is preferable to coat the upper surface and the side surface of the LED chip with the phosphor sheet from the viewpoint of expanding the light emission angle and reducing the unevenness in orientation. More preferably, the upper surface and the side surface of the LED chip are coated with the phosphor sheet in direct contact with each other. By using the laminate of the present invention, it is possible to produce a light-emitting device in which 80% or more of the upper light-emitting surface area of the LED chip and 50% or more of the side light-emitting area of the LED chip are directly covered by the phosphor sheet pasted on the laminate. . Finally, it is also possible to produce a light-emitting device in which 100% or more of the upper light-emitting surface area of the LED chip and 50% or more of the side light-emitting area of the LED chip are directly covered by the phosphor sheet pasted from the laminate.

Here, the term "directly adhered" refers to a state in which there is no gap or the like between the phosphor sheet and the upper light emitting surface or side light emitting surface of the LED chip. In the coating of the light-emitting surface on the upper part of the LED chip, if there are few directly bonded parts, the phosphor sheet may be easily peeled off, which may cause a defect in the light-emitting device. In the present invention, when the direct bonding portion is substantially 80% or more of the area of the light-emitting surface of the upper part of the LED chip, peeling of the phosphor sheet is less likely to occur, and defects in the light-emitting device can be suppressed. From this point of view, the direct contact portion is more preferably 90% or more of the area of the upper light emitting surface, most preferably substantially 100%. The direct bonding portion is substantially 100% refers to the following state, that is, when the cross-section of the LED chip covered with the phosphor sheet is observed with a microscope at a magnification of 500 times, relative to the light emission of the LED chip As for the area of the surface, the area of the phosphor sheet that is in direct contact with the LED chip (light-emitting surface) is 100%.

In addition, if an air layer with a low refractive index exists between the light emitting surface of the LED chip and the phosphor sheet, light emission efficiency will decrease. Therefore, in the coating of the side light-emitting surface of the LED chip, if the direct bonding part is substantially smaller than 50% of the side light-emitting area of the LED chip, the luminous efficiency from the side of the LED chip may decrease and the brightness may decrease. . That is, in the coating of the side light emitting surface of the LED chip, when the direct bonding portion is 50% or more of the side light emitting area of the LED chip, it is possible to suppress a decrease in light emission efficiency from the side surface of the LED chip. From this point of view, the direct bonding portion is preferably 70% or more of the light emitting area of the side portion of the LED chip, more preferably 90% or more.

In the light-emitting device obtained by using the laminate of the present invention, from the viewpoint of suppressing azimuth unevenness of light emission, it is preferable that the film thickness of the phosphor sheet covering the LED chip varies little at any position, Since the luminous intensity from the surface is weaker than that from the side, it is preferable that the film thickness of the side surface of the LED chip be thinner than that of the top surface of the chip. Here, the azimuth unevenness of light emission means that the visual effect of the light from the light emitting device ("see え square" in Japanese) varies depending on the angle. Such azimuth unevenness can be determined by the color temperature at a distance of 10 cm from the upper surface of the LED chip of the light-emitting device in the vertical direction (hereinafter referred to as the vertical color temperature) and the upper surface of the LED chip of the light-emitting device at an angle of 45°. The color temperature at a distance of 10 cm (hereinafter referred to as 45° color temperature) is judged by the absolute value of the difference. In the present invention, the smaller the absolute value of the difference, the smaller the azimuth unevenness of light emission, which is preferable.

From the above viewpoint, in the present invention, in the portion (area) where the LED chip 14 and the phosphor sheet 3 are in contact with the upper surface of the LED chip 14, from the upper surface of the LED chip 14 to the outer surface of the phosphor sheet 3 The distance is set as the distance a [μm], the distance from the side surface of the LED chip 14 to the outer surface of the phosphor sheet 3 in the portion (area) where the LED chip 14 and the phosphor sheet 3 are in contact with the side face of the LED chip 14 When the distance b [μm] is used, it is preferable to satisfy the relationship of 0.80<a/b<1.50, more preferably 1.00<a/b<1.20, and still more preferably 1.00<a/b< 1.05.

That is, in the light-emitting device of the present invention, it is preferable that the relationship of [a/b] satisfies the above range. In addition, when producing the above-mentioned light-emitting device, it is preferable to adopt a production method in which the relationship of [a/b] satisfies the above-mentioned range in the obtained light-emitting device.

Therefore, in order to satisfy the above relationship, a preferred manufacturing method for obtaining the light-emitting device of the present invention includes bonding the LED chip (in particular, the light-emitting surface of the LED chip, or The upper surface and the side surface) are coated (coating process).

As described above, the manufacturing method for obtaining the light-emitting device of the present invention is preferably a method of manufacturing a light-emitting device that satisfies the above relationship in the step of coating with the phosphor sheet of the laminate of the present invention (coating step).

Example

Hereinafter, the present invention will be described more specifically by way of examples.

<Phosphor sheet>

·Silicone resin 1:

Resin main component (MeViSiO _2/2 ) _0.25 (Ph ₂ SiO _2/2 ) _0.3 (PhSiO _3/2 ) _0.45 (HO _1/2 ) _0.03 75 parts by weight

Hardness regulator ViMe ₂ SiO (MePhSiO) _17.5 SiMe ₂ Vi 10 parts by weight

Crosslinking agent (HMe ₂ SiO) ₂ SiPh ₂ 25 parts by weight

※ Among them, Me: methyl, Vi: vinyl, Ph: phenyl

0.025 parts by weight of reaction inhibitor 1-ethynyl hexanol

Platinum catalyst Platinum (1,3-divinyl-1,1,3,3-tetramethyldisiloxane) complex 1,3-divinyl-1,1,3,3-tetramethyldisiloxane Disiloxane solution [platinum content is 5% by weight] 0.01 parts by weight

- Silicone resin 2: KER6075 (manufactured by Shin-Etsu Chemical Co., Ltd.).

- Phosphor 1: NYAG-02 (manufactured by Intematix: Ce-doped YAG-based phosphor, specific gravity: 4.8 g/cm ³ , D50: 7 μm).

(Measuring method of storage modulus of phosphor sheet)

Measuring device: viscoelasticity measuring device ARES-G2 (manufactured by TAINSTRUMENTS)

Geometry: Parallel circular plate type (15mm)

Strain: 1%

Angular frequency: 1Hz

Temperature range: 25℃～140℃

Heating rate: 5°C/min

Measuring atmosphere: in the atmosphere.

16 phosphor sheets with a film thickness of 50 μm were laminated and bonded by thermocompression on a hot plate at 100° C. to produce an integrated film (sheet) of 800 μm, which was cut into a diameter of 15 mm and used as a measurement sample. This sample was measured using the above conditions, and the storage modulus at 25°C and 100°C was measured.

(Manufacturing method of phosphor sheet)

[Manufacturing Example 1 of Phosphor Sheet]

Using a container made of polyethylene with a volume of 300 ml, they were mixed at a ratio of 30% by weight of the silicone resin 1 and 70% by weight of the phosphor 1 . Thereafter, the mixture was stirred and defoamed at 1000 rpm for 20 minutes using a planetary stirring and defoaming device "MAZERUSTARKK-400" (manufactured by KURABO), to obtain a phosphor dispersion for sheet preparation. Use a slot die coater to coat the phosphor dispersion liquid for sheet preparation on "Cerapeel" WDS (manufactured by Toray Film Processing Co., Ltd.; film thickness: 50 μm, elongation at break: 115%, Young's The peeling surface with a modulus of 4500 MPa) was heated at 120° C. for 1 hour and dried to obtain a phosphor sheet 1 having a film thickness of 50 μm and a size of 100 mm square. The storage modulus of the phosphor sheet was 1.0 MPa at 25°C and 0.025 MPa at 100°C.

[Manufacturing Example 2 of Phosphor Sheet]

Except having used the silicone resin 2 instead of the silicone resin 1, it carried out similarly to manufacture example 1, and obtained the phosphor sheet 2 with a film thickness of 50 micrometers and 100 mm square. The storage modulus of this phosphor sheet was 1.1 MPa at 25°C and 0.35 MPa at 100°C.

<Laminate>

(support substrate)

The elongation at break and the Young's modulus of the support substrate at 23° C. were measured three times by a method based on ASTM-D882-12 using Tensilon RTF-1310 (manufactured by A&D), and the average value was obtained.

Sample size: width 10mm, initial length 30mm

Measuring conditions: temperature 23°C, tensile speed 300mm/min.

・Support base material 1: Polyurethane film MG90 (manufactured by Takeda Sangyo)

Film thickness 50μm, elongation at break 500%, Young's modulus 8MPa

・Support base material 2: Polyurethane film MG90 (manufactured by Takeda Sangyo)

Film thickness 100μm, elongation at break 750%, Young's modulus 8MPa

・Support base 3: Polyvinyl chloride film (soft) C+ type (manufactured by Achilles)

Film thickness 50μm, elongation at break 350%, Young's modulus 250MPa

・Support substrate 4: Polyvinyl chloride film T-80MW with adhesive (manufactured by Denki Kagaku Kogyo)

Film thickness 50μm, elongation at break 300%, Young's modulus 300MPa

・Supporting substrate 5: Silicone film Silicon tree (Japanese: Silicon tree) (manufactured by Mitsubishi Plastics)

Film thickness 50μm, elongation at break 450%, Young's modulus 1.6MPa

・Support substrate 6: Ethylene-tetrafluoroethylene copolymer (ETFE) film NEOFLONEF-0050 (manufactured by Daikin)

The film thickness is 50 μm, the elongation at break is 450%, and the Young's modulus is 640 MPa.

[manufacturing example 1]

The support substrate 1 is placed on the phosphor sheet 1 formed on the "Cerapeel" WDS, and it is extruded using a roll-type thermal laminator at a temperature of 80°C, a pressing pressure of 0.3MPa, and a conveying speed of 0.5m/min. pressure. After standing to cool and returning to room temperature, the "Cerapeel" WDS was peeled off to obtain a laminate 1 .

[Manufacturing example 2]

A laminate 2 was obtained in the same manner as in Production Example 1 except that the phosphor sheet 2 was used instead of the phosphor sheet 1 .

[Manufacturing example 3]

A laminate 3 was obtained in the same manner as in Production Example 1 except that the support base material 2 was used instead of the support base material 1 .

[Manufacturing example 4]

A laminate 4 was obtained in the same manner as in Production Example 1 except that the support base material 3 was used instead of the support base material 1 .

[Manufacturing example 5]

On the phosphor sheet 1 formed on the "Cerapeel" WDS, the support substrate 4 was placed so that the adhesive layer and the phosphor layer were in contact, and the pressure was applied at a temperature of 25°C and a pressure using a roll laminator. Extrusion was carried out under the conditions of 0.3MPa and conveying speed of 1.0m/min. After standing to cool and returning to room temperature, the "Cerapeel" WDS was peeled off to obtain a laminate 5 .

[Manufacturing example 6]

The supporting substrate 5 is placed on the phosphor sheet 1 formed on the "Cerapeel" WDS, and extruded using a roll-type thermal laminator at a temperature of 80°C, a pressing pressure of 0.3MPa, and a conveying speed of 0.5m/min. pressure. After standing to cool and returning to room temperature, the "Cerapeel" WDS was peeled off to obtain a laminated body 6 .

[Manufacturing example 7]

A laminate 7 was obtained in the same manner as in Production Example 1 except that the support base material 6 was used instead of the support base material 1 .

In addition, the laminated body of "Cerapeel" WDS produced in the manufacture example 1 of a fluorescent substance sheet, and the fluorescent substance sheet 1 was made into the laminated body 8.

<Light emitting element>

(pasting device)

Using a vacuum laminator V130 (manufactured by NichigoMorton) as shown in FIG. Material pressing mechanism.

(Evaluation of visual effects of light from light-emitting devices)

Determine the color temperature at a distance of 10 cm from the upper surface of the LED chip of the light-emitting device in the vertical direction (hereinafter referred to as the vertical color temperature) and the color temperature at a distance of 10 cm from the upper surface of the LED chip of the light-emitting device above an inclination of 45°. The absolute value of the difference in color temperature (hereinafter referred to as 45° color temperature) is judged as follows.

A:|(vertical color temperature)-(45°color temperature)|＜500K

B: 500K≤|(vertical color temperature)-(45°color temperature)|＜1000K

C: 1000K≤|(vertical color temperature)-(45°color temperature)|.

(followability evaluation method)

For a light-emitting device in which an LED chip is bonded to a substrate and covered with a phosphor sheet, a cross-section was cut perpendicular to the substrate at positions I, II, and III shown in FIG. 4 , and a cross-sectional view was taken by SEM. Next, the ratio of the portion where the phosphor sheet contacts the upper light emitting surface of the LED chip was calculated from each cross-sectional view. It should be noted that, in FIG. 4 , A/D=1/10, B/D=5/10, and C/D=9/10.

In addition, the ratio of the portion of the phosphor sheet in contact with the side light emitting surface of the LED chip was calculated in the same manner. For each ratio, the average value of the measurement results at three places was used as the followability to the upper light emitting surface and the followability to the side light emitting surface, and the followability was evaluated according to the following criteria.

A: The followability of the upper light emitting surface of the LED is 100%, and the followability of the side light emitting surface is 90% or more

B: The followability of the upper light emitting surface of the LED is 100%, and the followability of the side light emitting surface is 70% or more and less than 90%

C: The followability of the upper light emitting surface of the LED is 100%, and the followability of the side light emitting surface is 50% or more and less than 70%

D: The followability of the upper light-emitting surface of the LED is 90% or more and less than 100%, or the followability of the side light-emitting surface is 40% or more and less than 50%.

E: The followability of the upper light emitting surface of the LED is less than 90%, or the followability of the side light emitting surface is less than 40%.

(Evaluation of film thickness uniformity)

From the SEM-based cross-sectional view obtained by the above-mentioned followability evaluation method, the distance from the upper surface of the LED chip 14 to the phosphor sheet in the portion where the LED chip 14 and the phosphor sheet 3 are in contact with the upper surface of the LED chip 14 was measured. 3 of the outer surface of the distance a (see Figure 4). In addition, the distance b from the side of the LED chip 14 to the outer surface of the phosphor sheet 3 in the portion where the LED chip 14 and the phosphor sheet 3 contact on the side of the LED chip 14 was similarly measured (see FIG. 4 ). When measuring distance a and distance b, measure with three effective figures. The value of a/b was obtained by rounding off the third decimal place, and the film thickness uniformity was evaluated according to the following criteria.

A: 1.00<a/b<1.05

B: 1.05≤a/b<1.20

C: 0.80<a/b≤1.00 or 1.20≤a/b<1.50

D: a/b≦0.80 or 1.50≦a/b, or a case where evaluation was not possible.

[Example 1]

An LED chip having a size of 1 mm square and a thickness of 150 μm was bonded to an alumina ceramic substrate provided with electrodes through gold bumps having a thickness of 10 μm. Then, the laminated body 1 was cut into 3 mm square, and it laminated|stacked so that the phosphor sheet surface may contact the upper surface of the LED chip after joining. Set it on the lower platen located inside the vacuum chamber of the vacuum laminator. Then, after heating the lower platen to 80° C., the vacuum chamber was sealed. The inside of the vacuum chamber was depressurized to 0.001 MPa with a vacuum pump, and then maintained for 30 seconds. Thereafter, air of 0.1 MPa was fed into the pressing mechanism to expand the fluorosilicone rubber sheet, and the laminated body 1 was pressed for 10 seconds so as to follow the shape of the LED chip. Then, the vacuum chamber was opened (that is, air was injected into the vacuum chamber to return to atmospheric pressure (0.1 MPa)), and the light-emitting device covered with the phosphor sheet was taken out. However, in this stage, the coated phosphor sheet is still in the B stage (semi-cured state).

After removing the supporting base material from the above-mentioned light-emitting device, it was heated in a constant temperature oven heated to 150° C. for 2 hours to fully cure the phosphor sheet to obtain the final light-emitting device. Pass a current of 30 mA to the obtained light-emitting device, thereby causing the light-emitting device to emit light, and measure the vertical color temperature at a position 10 cm away from the light-emitting surface of the LED chip in the vertical direction (vertical line direction) and the vertical color temperature at a position formed by the vertical line. The angle is the 45° color temperature at a position 10cm away from the light-emitting surface of the LED chip in the direction of 45° (inclined 45° direction), so as to evaluate the visual effect of light. Then, the cross-section of the light-emitting element evaluated for the visual effect of light was cut perpendicular to the substrate, and a cross-sectional view was taken by SEM. Trackability and film thickness uniformity were evaluated from this cross-sectional view.

[Embodiments 2-6]

A light-emitting device was obtained in the same manner as in Example 1 except that the laminate described in Table 1 was used. Regarding the obtained light-emitting device, the visual effect, followability, and film thickness uniformity of light were evaluated in the same manner as in Example 1.

[Comparative examples 1-2]

A light-emitting device was obtained in the same manner as in Example 1 except that the laminate described in Table 1 was used. Regarding the obtained light-emitting device, the visual effect, followability, and film thickness uniformity of light were evaluated in the same manner as in Example 1.

From the results of the examples, it can be seen that by using a laminate having a supporting base material and a phosphor sheet having an elongation at break of 200% or more at 23°C and a Young's modulus of 600 MPa or less, the phosphor sheet can be used in Cover LED chips while maintaining followability and uniformity of film thickness.

In addition, as a result of making the above-mentioned light-emitting device emit light, the light-emitting element of the example uniformly emitted light from any direction, while the light-emitting element of the comparative example looked slightly dark when viewed from an oblique direction. From this, it can be seen that azimuth unevenness has occurred.

As described above, the difference between the color temperature of the LED chip in the vertical direction and the color temperature in the direction inclined at 45° is small for the light-emitting element that can be pasted with excellent trackability and film thickness uniformity using the laminate of the present invention. , it can be seen that azimuth unevenness can be suppressed.

Symbol Description

1 laminate

2 supporting substrate

3 phosphor sheets

4 Adhesive material (adhesive layer)

5 vacuum chamber

6 upper platen

7 lower platen

8 flexible sheets

9 Confined space (for pressing mechanism)

10 Air injection and discharge port (for press mechanism)

11 pressing mechanism

12 Air injection and exhaust port (for vacuum chamber)

13 Substrate

14 LED chips

15 light emitting device

16 Covering parts on the upper surface and side surfaces of the LED chip

17 Coating part in base material

18 bumps (for example, gold bumps)

Claims (7)

1. a duplexer, it comprises supporting substrate and fluorophor sheet material, described fluorophor sheet material contains fluorophor and resin, wherein, elongation at break when utilizing 23 DEG C of the described supporting substrate that tension test obtains is more than 200%, and Young's modulus when the 23 of described supporting substrate DEG C is below 600MPa.

2. duplexer as claimed in claim 1, wherein, Young's modulus during 23 DEG C of described supporting substrate is below 400MPa.

3. duplexer as claimed in claim 1, wherein, Young's modulus during 23 DEG C of described supporting substrate is below 100MPa.

4. duplexer as claimed any one in claims 1 to 3, wherein, described supporting substrate is polrvinyl chloride or polyurethane.

5. a manufacture method for light-emitting device, it includes following coating operation: would be engaged to the operation that the fluorophor sheet material of the duplexer according to any one of light-emitting area Claims 1-4 of the LED chip on substrate carries out being coated to.

6. a manufacture method for light-emitting device, it includes following coating operation: would be engaged to the operation that the fluorophor sheet material of the duplexer according to any one of the upper surface of the LED chip on substrate and side Claims 1-4 carries out being coated to.

7. the manufacture method of the light-emitting device as described in claim 5 or 6, wherein, described LED chip and described fluorophor sheet material in the part of the upper surface of LED chip from LED chip upper surface to the distance a of fluorophor sheet material outer surface and described LED chip and described fluorophor sheet material the part of the contacts side surfaces of LED chip meet from LED chip side to the distance b of fluorophor sheet material outer surface 1.00 < a/b < 1.20 relation, described distance a, distance b unit be ��m.