JP5720359B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device, and more particularly to a light emitting device including a light emitting element connected to a conductive member.

  Conventionally, in a light-emitting device using a light-emitting element as a light source, a highly light-reflective plating is applied to a conductive member such as a lead frame in order to increase light extraction efficiency. This plating is caused by sulfur-containing gas in the air. There is a problem of deterioration such as discoloration.

  In order to solve such a problem, for example, in Patent Document 1, a pair of metal electrodes, an optical semiconductor chip electrically connected to the pair of metal electrodes, and a part of the optical semiconductor chip and the metal electrode are sealed. A translucent resin, and the translucent resin is an epoxy resin cured with a polythiol-based curing agent, and suppresses the formation of sulfide on part or all of the surface of the metal electrode in contact with the translucent resin A light emitting diode provided with a protective film is described.

JP 2007-109915 A

  However, even in the light-emitting diode described in Patent Document 1, it is difficult to completely prevent the deterioration of the metal electrode because there is a sulfur-containing gas that permeates the protective film.

  Then, this invention is made | formed in view of this situation, and it aims at providing the light-emitting device which can suppress deterioration of the electrically-conductive member by sulfur containing gas by means different from the conventional protective film. To do.

  In order to solve the above problems, a light-emitting device according to the present invention includes a conductive member, a light-emitting element connected to the conductive member, a part of the conductive member and a sealing member that seals the light-emitting element, The sealing member includes, in its base material, first particles and second particles of a substance different from the first particles attached to the first particles, and the second particles are Oxide, hydroxide or carbonate of at least one element selected from potassium, calcium, sodium, magnesium, manganese, zinc, iron, copper, nickel, silver, zirconium, cobalt, chromium, lead, barium, Alternatively, these compounds are included.

  Another light-emitting device according to the present invention includes a conductive member, a light-emitting element connected to the conductive member, a part of the conductive member and a sealing member that seals the light-emitting element, The sealing member contains zinc hydroxide or carbonate or particles containing these compounds in the base material.

  According to the light emitting device of the present invention, the particles of the substance that easily reacts with sulfur (second particles) added to the sealing member react preferentially with the sulfur-containing gas in the air, so that the conductive member Deterioration can be suppressed.

It is the schematic top view (a) of the light-emitting device which concerns on one embodiment of this invention, and the schematic sectional drawing (b) in the AA cross section. It is a schematic sectional drawing of the light-emitting device which concerns on one embodiment of this invention.

  Hereinafter, embodiments of the invention will be described with reference to the drawings as appropriate. However, the light emitting device described below is for embodying the technical idea of the present invention, and the present invention is not limited to the following. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the constituent elements described below are not intended to limit the scope of the present invention only to specific examples unless otherwise specified. Only. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation.

<Embodiment 1>
FIG. 1A is a schematic top view of the light-emitting device according to Embodiment 1, and FIG. 1B is a schematic cross-sectional view showing the AA cross section in FIG. The light emitting device 100 of the example illustrated in FIG. 1 includes a conductive member 10, a light emitting element 20 connected to the conductive member 10, and a sealing member 30 that seals a part of the conductive member 10 and the light emitting element 20. ing.

  More specifically, the base body 60 of the light emitting device 100 is a package in which a top surface is opened and a recess having an inner side wall and a bottom surface is formed. The conductive member 10 is a pair of positive and negative lead frames integrally held on the base body 60, and a part of the surface of the conductive member 10 constitutes a part of the bottom surface of the recess of the base body 60. The surface of the conductive member 10 is plated with a metal having a high light reflectivity with respect to the light emitted from the light emitting element. The light emitting element 20 is bonded to the bottom surface of the recess of the base body 60 with an adhesive, and is electrically connected to the conductive member 10 with a wire 50. The sealing member 30 is filled in the concave portion of the base body 60 and covers the light emitting element 20 and the wire 50.

And the sealing member 30 contains in the base material the 1st particle | grains 41 and the 2nd particle | grains 42 of the substance different from the 1st particle | grains adhering to this 1st particle | grain. The second particles 42 are potassium, calcium, sodium, magnesium, manganese, zinc, iron, copper, nickel, silver, zirconium, cobalt, chromium, lead, barium (hereinafter, these elements are collectively referred to as “element group G”). An oxide, hydroxide or carbonate of at least one element selected from the above, or a compound thereof. Specifically, for example, basic zinc carbonate _{(ZnCO 3 · Zn (OH)} 2) include basic carbonates such.

  Here, silver, aluminum, rhodium, etc. are mentioned as a material suitable for the plating formed in the surface layer of an electrically-conductive member, or a light reflection film. Among them, silver has a high light reflectance of 95% or more in a wide range of visible wavelength region. However, silver has a drawback that it is relatively easy to react with sulfur and turns black when sulfurized. For example, considering a lead frame in which iron or copper is used as a base material and silver plating is applied to it, silver is easy to sulfidize in an atmosphere containing hydrogen sulfide, among other sulfur-containing gases. Sulfidation is likely in an atmosphere containing sulfur oxides (especially sulfur dioxide). In a gas atmosphere containing hydrogen sulfide and sulfur oxide, such as in the air, the silver plating on the surface layer is first sulfided, and then, or in parallel, the sulfurization reaction to a deeper base material proceeds.

  Therefore, the conventional means described above suppresses the sulfur-containing gas from reaching the conductive member by separately providing a protective film having a high gas barrier property on the conductive member. On the other hand, in the present invention, the second particles as described above are added in advance to a part of the conductive member and a sealing member for sealing the light emitting element. Thereby, since the 2nd particle in a sealing member reacts preferentially with sulfur content gas, arrival of a sulfur content gas to a conductive member can be controlled. In addition, this is a relatively easy and inexpensive means that can be achieved by adding particles to the sealing member. Furthermore, since it is completely different from the conventional means for providing a protective film separately, it can be combined with the conventional means, thereby further suppressing the deterioration of the conductive member.

  In particular, as shown in FIG. 1B, the second particles 42 are preferably present in the sealing member 30 in a state of being attached to the first particles 41. Such second particles 42 are formed by surface treatment of the first particles 41 as will be described later, and are then added to the sealing member 30. By adding the second particle 42 to the sealing member 30 in a state of adhering to the first particle 41, the aggregation of the second particle 42 is suppressed, and compared with the case where the second particle 42 is added alone. The two particles 42 are easily provided in small portions in the sealing member 30. Therefore, even if the addition amount is equal, the surface area of the second particles 42 can be increased, and the sulfur-containing gas can be reacted efficiently. As a result, since deterioration of the conductive member 10 can be suppressed with a smaller addition amount, high light extraction efficiency can be maintained.

  Although the adhesion form of the second particles 42 to the first particles 41 may enclose substantially the entire surface of the first particles 41, as shown in FIG. It is preferable that it adheres to a part. Thereby, it is easy to enlarge the surface area of the 2nd particle | grains 42, and to make it react easily with sulfur containing gas. In addition, a part of the surface of the first particle 41 is exposed from the second particle 42, and light is easily incident on the first particle 41, and the optical function of the first particle 41 is easily utilized. Note that all of the second particles 42 present in the sealing member 30 may be attached to the first particles 41, or the second particles 42 attached to the first particles 41 and the second particles existing alone. 42 may be mixed.

  Adhesion of the second particles 42 to the first particles 41 can be realized by the following method. First, the first particles 41 are dispersed in pure water, and at least one water-soluble compound selected from the oxides, sulfates and nitrates of the element group G is added and stirred. Next, a base selected from sodium hydroxide and ammonium hydrogen carbonate is added dropwise to the suspension to adjust the pH to a range of 7.0 to 11.5. Finally, the generated precipitate may be sufficiently washed, drained, dried, sieved, and the like. According to such a method, the particle size of the second particles 42 can be easily controlled, and the second particles 42 can be divided into small pieces and attached to the first particles 41. In addition, the second particles 42 may be sprayed and adhered to the first particles 41 with a spraying device.

  The smaller the particle size of the second particles 42, the larger the ratio of the surface area to the added amount, and the second particles 42 can be efficiently reacted with the sulfur-containing gas. The particle size of the second particles 42 is preferably smaller than the particle size of the first particles 41. Specifically, the particle size of the second particles 42 depends on the particle size of the first particles 41, but is, for example, 2.5 nm to 100 μm, preferably 0.05 μm to 3 μm. The particle size of the first particles 41 is, for example, 5 nm to 200 μm, preferably 0.5 μm to 20 μm.

  Moreover, the 2nd particle | grains 42 can raise the deterioration inhibitory effect of the electrically-conductive member 10 by sulfur containing gas, so that the addition amount is large. However, the addition amount of the second particles 42 may be determined in consideration of changes in the viscosity of the sealing member 30 and the light extraction efficiency due to the addition of the particles. Specifically, the added amount of the first particles 41 to which the second particles 42 adhere or the second particles 42 alone is, for example, 1 wt% or more and 100 wt% or less, preferably with respect to the weight of the base material of the sealing member 30. Is 5 wt% or more and 30 wt% or less.

  The second particles 42 are preferably a white substance that can easily maintain light extraction efficiency even when added to the sealing member 30. Further, the second particles 42 remain in the sealing member 30 even after being sulfided. For this reason, the 2nd particle | grains 42 react with a sulfur containing gas, and the substance which produces | generates a white sulfide is preferable because it is easy to maintain the light extraction efficiency. In particular, in the element group G, zinc tends to produce a white compound and is white after sulfidation. For this reason, it is preferable that the 2nd particle | grains 42 contain the oxide, hydroxide, or carbonate of zinc, or these compounds.

  The second particles 42 may contain a plurality of oxides, hydroxides or carbonates of the element group G, or these compounds. For example, the second particles 42 include a first substance that becomes white after sulfiding and a second substance that becomes black or colored after sulfiding but has a higher reactivity with sulfur than the first substance. It is possible to achieve a balance between suppression of deterioration of the member 10 and maintenance of light extraction efficiency. In this case, the particles of the first substance adhere to the particles of the second substance or encapsulate the surface of the particles of the second substance, for example, the particles of the first substance are provided after the particles of the second substance. It is even better if it is provided.

  In the example shown in FIG. 1B, the second particles 42 are unevenly distributed on the conductive member 10 side in the sealing member 30, for example, by sinking to the bottom surface side of the recess of the base body 60. In other words, on the surface side in the sealing member 30, there is a layered base material region in which the base material of the sealing member occupies most. In this case, the base material region is first formed by the second particles 42 that are further unevenly distributed on the conductive member 10 side while suppressing the permeation of the sulfur-containing gas to the deep layer by utilizing the gas barrier property of the base material itself of the base material region. The sulfur-containing gas that has permeated can be prevented from reaching the conductive member 10. Therefore, deterioration of the conductive member 10 due to the sulfur-containing gas can be efficiently suppressed. Conversely, when the second particles 42 are unevenly distributed on the surface side in the sealing member 30, the second particles 42 unevenly distributed on the surface side easily suppress the permeation of the sulfur-containing gas to the deep layer, Further, the light shielding by the second particles 42 is reduced, and it is easy to utilize the plating of the conductive member 10 and the optical function of the light reflecting film. Furthermore, when the second particles 42 are dispersed over substantially the entire region of the sealing member 30, it is possible to obtain an intermediate and balanced characteristic between the two uneven distribution forms described above.

<Embodiment 2>
FIG. 2 is a schematic cross-sectional view of the light emitting device according to the second embodiment. The base 60 of the light emitting device 200 of the example shown in FIG. 2 is a wiring board including the conductive member 10 that is a wiring electrode on the upper surface thereof. A frame body is provided on the upper surface of the base body 60. The light emitting element 20 is bonded to the conductive member 10 of the base body 60 with a conductive adhesive 55 in the frame. The conductive member 10 in the frame has a metal light reflecting film having high light reflectivity with respect to the light emitted from the light emitting element 20 on the uppermost layer. The sealing member 30 is filled in the frame to seal the light emitting element 20, and the outer surface thereof is formed into a convex curved surface.

  And the sealing member 30 contains the 2nd particle | grains 42 in the base material. The second particles 42 include an oxide, hydroxide or carbonate of at least one element selected from the element group G, or a compound thereof. In particular, the second particles 42 are preferably particles containing zinc hydroxide or carbonate, or a compound thereof, like the basic zinc carbonate. Of course, even if the second particle 42 is added to the sealing member alone, the second particle 42 has an effect of suppressing the arrival of the sulfur-containing gas to the conductive member. Further, as shown in FIG. 2, the second particles 42 of the present embodiment are dispersed substantially uniformly in the sealing member 30.

  The simple substance of the second particle 42 is obtained by the following method. First, at least one water-soluble compound selected from the oxides, sulfates and nitrates of the element group G is added to pure water and stirred. Next, a pH selected from 7.0 to 11.5 is adjusted by dropping a base selected from sodium hydroxide and ammonium hydrogen carbonate into the suspension. Finally, the generated precipitate may be sufficiently washed, drained, dried, sieved, and the like.

  Hereinafter, each component of the light emitting device of the present invention will be described.

(Conductive member 10)
As the conductive member, a metal member that is electrically connected to the light emitting element can be used. Specific examples include lead frames and wiring electrodes formed of copper, aluminum, gold, silver, tungsten, iron, nickel, or alloys thereof, phosphor bronze, iron-containing copper, and the like. Further, a plating such as silver, aluminum, rhodium, gold, copper, or an alloy thereof, or a light reflecting film may be provided on the surface layer.

(Light emitting element 20)
As the light emitting element, a semiconductor light emitting element such as a light emitting diode or a semiconductor laser can be used. The light emitting element may be any element in which a pair of positive and negative electrodes is provided in an element structure composed of various semiconductors. In particular, a light-emitting element of a nitride semiconductor (In _x Al _y Ga _1-xy N, 0 ≦ x, 0 ≦ y, x + y ≦ 1) that can excite the phosphor efficiently is preferable. In addition, a gallium arsenide-based or gallium phosphorus-based semiconductor light emitting element emitting green to red light may be used. In the case of a light-emitting element in which a pair of positive and negative electrodes are provided on the same surface side, the mounting form may be face-up mounting in which each electrode is connected to a conductive member with a wire, or each electrode is conductive with a conductive adhesive. Face-down (flip chip) mounting connected to the member may be used. In addition, a light emitting element having a counter electrode structure in which a pair of positive and negative electrodes are provided on opposite surfaces may be used. The number of light emitting elements mounted on one light emitting device may be one or plural.

(Sealing member 30)
The sealing member is a member that seals a part of the light emitting element, the wire, and the conductive member to protect them from dust, moisture, external force, and the like. The base material of the sealing member may be formed of a material that can transmit light emitted from the light-emitting element (preferably a transmittance of 70% or more). Specifically, silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, ABS resin, polybutylene terephthalate resin, polyphthalamide resin, polyphenylene sulfide resin, liquid crystal polymer, or a hybrid containing one or more of these resins Resin. Glass may be used. Among these, silicone resins are superior in heat resistance and light resistance to epoxy resins and the like, but have low gas barrier properties. Therefore, the gas barrier property can be more preferably used by supplementing the gas barrier properties by adding the second particles. Light distribution characteristics can be adjusted by molding the outer surface of the sealing member into various lens shapes such as convex and concave lenses, and uneven surfaces that scatter light.

(First particle 41)
The sealing member may have particles having various functions added to its base material. As the first particles, filler particles or phosphor particles can be used. In particular, the filler is preferable because it has a small influence on the emission wavelength of the light-emitting device. As the filler, a light diffusing agent or a coloring agent can be used. Specifically, silica, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, zinc oxide, barium titanate, aluminum oxide, iron oxide, chromium oxide, manganese oxide, carbon black, etc. Can be mentioned. The shape of the filler particles may be crushed or spherical. Further, it may be hollow or porous. The phosphor absorbs at least part of the primary light emitted from the light emitting element, and emits secondary light having a wavelength different from that of the primary light. Specific examples include yttrium aluminum garnet (YAG) activated with cerium and nitrogen-containing calcium aluminosilicate (CaO—Al ₂ O ₃ —SiO ₂ ) activated with europium and / or chromium. Thus, a light emitting device that emits mixed light (for example, white light) of primary light and secondary light having a visible wavelength, or a light emitting device that emits visible light secondary light when excited by the primary light of ultraviolet light is used. Can do.

(Wire 50, conductive adhesive 55)
As the wire, a metal wire of gold, copper, platinum, aluminum, or an alloy thereof can be used. In particular, a gold wire having excellent thermal resistance is preferable. As the conductive adhesive, bumps or pastes such as silver, gold, and gold-tin can be used. By adding the second particles to the sealing member, it is possible to suppress the deterioration of the wire or the conductive adhesive due to the sulfur-containing gas.

(Substrate 60)
The base is a member serving as a base on which the light emitting element is placed. The base may be in the form of a package having a recess including a part of the conductive member on the bottom surface, in the form of a substrate not having a recess (side wall), or in the form of a substrate provided with a frame. When a part of the sealing member is covered with the concave portion or the frame of the base body, it is possible to easily suppress the intrusion of the sulfur-containing gas into the sealing member. The packaging and frame materials are made by adding the same fillers as described above to base materials such as polyphthalamide resin, polybutylene terephthalate resin, bismaleimide triazine resin, liquid crystal polymer, epoxy resin, silicone resin, and polyimide resin. Can be mentioned. The second particles may be added to such a package or frame. The substrate can be formed of glass epoxy, glass, ceramics, aluminum, or the like. In addition, a conductive member such as a lead frame may also serve as a base, like a bullet-type LED.

  Examples according to the present invention will be described in detail below. Needless to say, the present invention is not limited to the following examples.

<Example 1>
The light-emitting device of Example 1 is an example of the light-emitting device 100 according to Embodiment 1, and the side light emission (side view) has an outer shape of 1.0 mm in length, 2.8 mm in width, and 0.8 mm in depth (height). This is a surface mount LED of the formula. The base body 60 is a package having a recess having a depth of 0.3 mm at the approximate center thereof, and has a modulus of elasticity of 6000 MPa and a linear expansion coefficient at room temperature (25 ° C.) of about 60 × 10 ⁻⁶ / K. It is formed of an amide resin. The conductive member 10 is a lead frame made of a copper alloy having a surface plated with silver, a part of which is exposed on the bottom surface of the recess of the package and extends to the outer surface of the package. Such a base body 60 is formed by installing the conductive member 10 in a mold and injecting and curing the constituent material of the package. The light-emitting element 20 is a light-emitting diode chip having a vertical length of 290 μm and a horizontal width of 500 μm that can emit blue light (center wavelength of about 460 nm), in which an n-type layer, an active layer, and a p-type layer of nitride semiconductor are sequentially stacked on a sapphire substrate. It is. The light emitting element 20 is bonded to one (negative electrode side) conductive member 10 with an adhesive, which is a translucent epoxy resin, in the concave portion of the base body 60, and each electrode is electrically connected to positive and negative electrodes by a gold wire 50. Each is connected to the member 10. The sealing member 30 is filled in the concave portion of the base body 60 so as to cover the light emitting element 20 and the wire 50. Such a sealing member 30 is formed by pouring the constituent material of the sealing member into the concave portion of the base body 60 by potting and curing. The base material of the sealing member 30 has a viscosity of 4 Pa · s, a linear expansion coefficient of about 300 × 10 ⁻⁶ / K at room temperature (25 ° C.), and a water vapor permeability of 150 g / m ² · day (0.9 mm thickness). , Test environment 40 ° C./90% RH) silicone resin.

  In the light emitting device of Example 1, the second basic zinc carbonate having a particle size of about 0.1 μm to 2 μm is formed on the surface of the first particle 41 of silica having an average particle size of 6.8 μm in the sealing member 30. The particle | grains 42 to which the particle | grains adhered are included. The particles are obtained by dispersing silica in pure water, adding zinc nitrate hexahydrate so that zinc derived therefrom is 2 wt% with respect to the weight of the silica, and stirring the suspension. After ammonium is added dropwise to adjust the pH to 7.8, it is obtained by thoroughly washing, draining, drying and sieving. The particles are added in an amount of 10 wt% with respect to the weight of the base material of the sealing member 30, and are dispersed over substantially the entire area in the sealing member 30.

  Hereinafter, in the light emitting devices of Examples 2 to 9 and Comparative Examples 1 and 2, the configuration excluding the particles added to the sealing member is the same as that of the light emitting device of Example 1, and thus the description thereof is omitted. In all of the following examples and comparative examples, the amount of particles added to the sealing member 30 is 10 wt% with respect to the weight of the base material of the sealing member 30.

<Examples 2 and 3>
In the light-emitting devices of Examples 2 and 3, the amount of the basic zinc carbonate second particles 42 added to the sealing member is increased from that of Example 1. In the light-emitting devices of Examples 2 and 3, zinc nitrate hexahydrate was added so that the zinc derived from it was 5 wt% and 10 wt% based on the weight of silica.

<Example 4>
The sealing member of the light emitting device of Example 4 is obtained by adding the basic second particles 42 of basic zinc carbonate instead of the first particles 41 to which the second particles 42 of Example 1 are attached. The particles were adjusted to pH 6.8 by adding ammonium hydrogen carbonate dropwise to an aqueous solution in which zinc nitrate hexahydrate was added so that zinc derived therefrom was 2 wt% based on the weight of pure water. Thereafter, it is obtained by sufficiently washing, draining, drying and sieving.

<Comparative Example 1>
The sealing member of the light emitting device of Comparative Example 1 is obtained by adding only the first silica particles 41 as in Example 1.

  Next, the effect of suppressing deterioration of the conductive member in the light emitting devices of Examples 1 to 4 is verified by a sulfidation test. This sulfurization test is performed by leaving the light-emitting device in a mixed gas atmosphere of hydrogen sulfide and sulfur dioxide. More specifically, a light emitting device and sodium sulfide hexahydrate are put in an autoclave, heated to 100 ° C., and left for 24 hours.

  The results of the sulfidation test are shown in Table 1 below. The relative luminous flux maintenance factor is a relative value when the luminous flux maintenance factor before and after the sulfidation test in the light emitting device of the comparative example is 1.000 and the luminous flux maintenance factor before and after the sulfidation test in each example is compared. is there. A higher relative luminous flux maintenance factor indicates a higher effect of suppressing deterioration of the conductive member.

  As shown in Table 1, the relative luminous flux maintenance factors of the light emitting devices of Examples 1 to 4 are larger than 1.000, and it can be seen that the addition of the second particles 42 can suppress the deterioration of the conductive member due to the sulfur-containing gas. . Note that the light emitting devices of Examples 1 to 4 maintain a high initial luminous flux value even when the second particles 42 are added. In particular, the initial luminous flux values of the light emitting devices of Examples 1 to 3 are the light emitting device of Example 4. Even higher than that. Thus, when the 2nd particle 42 is added in the state adhering to the 1st particle 41, it is easy to suppress deterioration of the electrically-conductive member by sulfur containing gas, and to maintain a high luminous flux value.

<Example 5>
In the light emitting device of Example 5, the first particles 41 of Example 1 are replaced with YAG phosphors having an average particle size of 8.0 μm, and the second particles 42 are replaced with zinc hydroxide. These particles are prepared by dispersing a YAG phosphor in pure water, adding zinc sulfate so that the zinc derived from it is 2 wt% with respect to the weight of YAG, stirring, and adding sodium hydroxide to the suspension. Is added dropwise to adjust the pH to 7.7, followed by thorough washing, draining, drying and sieving.

<Example 6>
The light emitting device of Example 6 is obtained by replacing the second particles 42 in the light emitting device of Example 5 with a mixture of zinc oxide and zinc hydroxide. In this particle, a YAG phosphor is dispersed in pure water, zinc oxide derived from zinc is 2 wt% based on the weight of YAG, and zinc sulfate derived from zinc is 0.5 wt% based on the weight of YAG. It is obtained by adding sodium hydroxide dropwise to the suspension and adjusting the pH to 7.7, followed by thorough washing, draining, drying and sieving. is there.

<Example 7>
In the light emitting device of Example 7, the second particles 42 in the light emitting device of Example 5 are replaced with iron hydroxide. These particles were prepared by dispersing a YAG phosphor in pure water, adding iron nitrate nonahydrate so that the iron derived from it was 2 wt% based on the weight of YAG, and stirring the suspension. After adjusting the pH to 7.7 by dropping sodium hydroxide, it is obtained by thoroughly washing, draining, drying and sieving.

<Example 8>
In the light emitting device of Example 8, the second particles 42 in the light emitting device of Example 5 are replaced with a mixture of zinc oxide and iron hydroxide. This particle is obtained by dispersing a YAG phosphor in pure water, zinc oxide derived from the zinc of 2 wt% based on the weight of the YAG, and iron nitrate nonahydrate based on the iron derived from the weight of the YAG. After adding and stirring to 0.5 wt%, sodium hydroxide was added dropwise to the suspension to adjust the pH to 7.5, and then thoroughly washed, drained, dried, and sieved. It is obtained.

<Example 9>
In the light emitting device of Example 9, the second particles 42 in the light emitting device of Example 5 are replaced with a mixture of zinc oxide and magnesium hydroxide. In this particle, a YAG phosphor is dispersed in pure water, zinc oxide derived from zinc is 2 wt% based on the weight of YAG, and magnesium nitrate derived from magnesium is 0.5 wt% based on the weight of YAG. After adding sodium hydroxide dropwise to the suspension and adjusting the pH to 11.5, the suspension is sufficiently washed, drained, dried and sieved. is there.

<Comparative Example 2>
The sealing member of the light emitting device of Comparative Example 2 is obtained by adding only the first particles 41 of the YAG phosphor similar to Example 5.

  Next, the effect of suppressing deterioration of the conductive member in the light emitting devices of Examples 5 to 9 is verified by the same sulfurization test as described above. The results of the sulfidation test are shown in Table 2 below.

  As shown in Table 2, also in the light emitting devices of Examples 5 to 9 in which the first particles 41 are phosphors, the relative luminous flux maintenance factor is larger than 1.000, and the addition of the second particles 42 contains sulfur. It can be seen that deterioration of the conductive member due to gas can be suppressed.

  In particular, it can be seen that the light emitting devices of Examples 7 and 8 in which the second particles 42 are a compound containing iron have a very high relative luminous flux maintenance factor and a high effect of suppressing deterioration of the conductive member of iron.

  The light emitting device according to the present invention includes a backlight source of a liquid crystal display, various lighting devices, a large display, various display devices such as advertisements and destination guidance, and an image reading device in a digital video camera, a facsimile, a copier, a scanner, and the like. It can be used for projector devices.

  DESCRIPTION OF SYMBOLS 10 ... Conductive member, 20 ... Light emitting element, 30 ... Sealing member, 41 ... 1st particle, 42 ... 2nd particle, 50 ... Wire, 55 ... Conductive adhesive, 60 ... Base | substrate, 100, 200 ... Light-emitting device

Claims (6)

A conductive member, a light emitting element connected to the conductive member, a part of the conductive member and a sealing member for sealing the light emitting element,
The sealing member includes, in the base material, first particles and second particles of a substance different from the first particles attached to the first particles,
The first particles are silica,
The second particles include an oxide of at least one element selected from potassium, calcium, sodium, magnesium, manganese, zinc, iron, copper, nickel, silver, zirconium, cobalt, chromium, lead, and barium, hydroxide A light emitting device comprising a product, a carbonate, or a compound thereof.   The light emitting device according to claim 1, wherein the second particles include zinc oxide, hydroxide, carbonate, or a compound thereof. A conductive member, a light emitting element connected to the conductive member, a part of the conductive member and a sealing member for sealing the light emitting element,
The sealing member includes, in the base material, first particles and second particles of a substance different from the first particles attached to the first particles,
The first particle is a phosphor,
The second particle is a carbonate of at least one element selected from potassium, calcium, sodium, magnesium, manganese, zinc, iron, copper, nickel, silver, zirconium, cobalt, chromium, lead, barium, or A light emitting device comprising a compound. The light emitting device according to any one of claims 1 to 3, wherein the second particles are attached to a part of a surface of the first particles. A conductive member, a light emitting element connected to the conductive member, a part of the conductive member and a sealing member for sealing the light emitting element,
The sealing member, its base material, the light emitting apparatus characterized by comprising particles alone containing carbon oxides or a compound of zinc. The light emitting device according to any one of claims 1 to 5 , wherein a base material of the sealing member is a silicone resin.

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