JP2014143344A - Wavelength conversion member and semiconductor light-emitting device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wavelength conversion member which does not reduce luminous efficiency of a semiconductor light-emitting device when the wavelength conversion member is provided in the semiconductor light-emitting device, and can reduce the cost by reducing the content of phosphor, and to provide a semiconductor light-emitting device using the wavelength conversion member.SOLUTION: A wavelength conversion member emits combined white light by performing wavelength conversion on incident blue light at least partially and combining visible light of a plurality of wavelengths. The wavelength conversion member includes: a transparent member consisting of a phosphor that emits light of a wavelength different from that of the blue light by absorbing the blue light at least partially, and a base material for holding the phosphor; and a filter having a mean transmittance of 20% or less in a range of incident angle from 0 to 30 degrees of first visible light composing the combined white light, and a mean transmittance of 80% or more in a range of incident angle from 0 to 30 degrees of second visible light composing the combined white light. The filter is located on the emission side of the combined white light.

Description

  The present invention relates to a wavelength conversion member that converts the wavelength of at least part of incident light and emits emitted light having a wavelength different from that of the incident light, and a semiconductor light emitting device using the wavelength conversion member and a semiconductor light emitting element.

  Incandescent light bulbs and fluorescent lamps have been widely used as light sources for light emitting devices. In recent years, in addition to these, semiconductor light-emitting devices using a semiconductor light-emitting element such as a light-emitting diode (LED) or an organic EL (OLED) as a light source have been developed and used. Since these semiconductor light emitting elements can obtain various emission colors, a plurality of semiconductor light emitting elements having different emission colors are combined, and the respective emission colors are combined to obtain a combined light of a desired color. Such semiconductor light emitting devices have been developed and used.

  For example, a red LED using an LED chip whose emission color is red, a green LED using an LED chip whose emission color is green, and a blue LED using an LED chip whose emission color is blue are combined and supplied to each LED. Japanese Patent Application Laid-Open No. 2004-151867 discloses a semiconductor light emitting device that emits desired white light by adjusting the driving current to be synthesized and combining the light emitted from each LED.

  Originally, since the emission spectrum width of the LED chip itself is relatively narrow, when the light emitted from the LED chip itself is used as it is for illumination, there is a problem that the color rendering properties that are important in general illumination light are lowered. Therefore, in order to solve such problems, an LED has been developed in which the light emitted from the LED chip is wavelength-converted by a wavelength conversion member such as a phosphor, and the light obtained by the wavelength conversion is emitted. A semiconductor light emitting device combining LEDs is disclosed in, for example, Patent Document 2.

  In the semiconductor light emitting device disclosed in Patent Document 2, a transparent resin is provided so as to cover an LED chip that emits blue light while being in contact with it, and a yellow phosphor is contained inside the transparent resin. That is, the semiconductor light emitting device disclosed in Patent Document 2 is provided with a wavelength conversion member so as to directly cover the LED chip. However, in the semiconductor light emitting device having such a structure, variations in luminance and color unevenness of the semiconductor light emitting device are large. In order to solve such a problem, research and development and commercialization of a semiconductor light-emitting device having a structure in which a phosphor-containing resin (that is, a wavelength conversion member or a phosphor layer) is arranged apart from an LED chip, In recent years, it has been actively performed. A semiconductor light emitting device having such a structure is disclosed in Patent Document 3, for example.

JP 2006-4839 A JP 2007-122950 A JP 2011-249768 A

  However, the structure in which the wavelength conversion member is provided apart from the LED chip is larger in the size of the wavelength conversion member than the structure in which the wavelength conversion member is provided so as to cover the LED chip so as to cover the LED chip. The amount of phosphor produced is increased. In general, when the wavelength conversion member is separated from the LED chip, a phosphor several times more than the conventional phosphor is required to obtain the same light emission efficiency as when the LED chip is directly covered with the wavelength conversion member. It becomes. Therefore, it is required to reduce the amount of phosphor used for the wavelength conversion member.

  From the above, in the semiconductor light emitting device having a structure in which the wavelength conversion member is provided apart from the LED chip, there is a problem that the amount of the phosphor is increased as compared with the conventional case, and the cost of the wavelength conversion member and the semiconductor light emitting device is increased. It was happening. In particular, when a single wavelength conversion member is provided for a large number of LED chips, the product cost has increased.

  The present invention has been made in view of such problems, and the object of the present invention is to provide a phosphor content without reducing the light emission efficiency of the semiconductor light emitting device when provided in the semiconductor light emitting device. It is providing the wavelength conversion member which can aim at cost reduction by reducing, and the semiconductor light-emitting device using the said wavelength conversion member.

In order to achieve the above object, the wavelength conversion member of the present invention is a wavelength conversion member that converts the wavelength of at least a part of incident blue light, synthesizes a plurality of visible lights, and emits synthetic white light,
A phosphor that absorbs at least part of the blue light and emits light having a wavelength different from that of the blue light, and a transparent member made of a base material that holds the phosphor, and the first that constitutes the synthetic white light The average transmittance in the range of the incident angle of 0 to 30 degrees of visible light is 20% or less, and the average transmittance in the range of the incident angle of 0 to 30 degrees of the second visible light constituting the synthetic white light is 80% or more of the filter, and the filter is located on the emission side of the synthetic white light.

  In order to achieve the above object, a semiconductor light-emitting device of the present invention includes the above-described wavelength conversion member and a semiconductor light-emitting element that emits the blue light toward the wavelength conversion member.

  In the wavelength conversion member and the semiconductor light-emitting device of the present invention, blue light can be favorably reflected toward the phosphor, so that desired white can be efficiently emitted even when the amount of phosphor used is small. can do.

It is a perspective view which shows the outline of the whole structure of the semiconductor light-emitting device based on an Example. It is a top view of the semiconductor light-emitting device concerning an example. FIG. 3 is a cross-sectional view of the semiconductor light emitting device taken along line III-III in FIG. 2. It is an expanded sectional view of the principal part in FIG. It is a figure which shows the evaluation result of the wavelength dependence of the transmittance | permeability in the incident angle of 0 degree | times of each sample filter. It is a figure which shows the evaluation result of the incident angle dependence of the transmittance | permeability with respect to the light whose wavelength of each sample filter is 450 nm. It is a figure which shows the evaluation result of the incident angle dependence of the average transmittance | permeability with respect to the light whose wavelength of each sample filter is 500 nm to 700 nm. It is a figure which shows the calculation result of the incident angle dependence of the average transmittance | permeability of the light of the blue area | region with respect to a transparent member. It is a figure which shows the incident angle dependence of the transmittance | permeability with respect to the light with a wavelength of 450 nm based on a modification. It is a figure which shows the incident angle dependence of the transmittance | permeability with respect to the light with a wavelength of 600 nm based on a modification.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited to the content demonstrated below, In the range which does not change the summary, it can change arbitrarily and can implement. In addition, the drawings used for the description of the embodiments schematically show the wavelength conversion member and the semiconductor light emitting device according to the present invention, and some emphasis, enlargement, reduction, omission, etc. are made to deepen the understanding. In some cases, it does not accurately represent the scale or shape of each component. Furthermore, the various numerical values used in the embodiments are only examples, and can be variously changed as necessary.

<Configuration of semiconductor light emitting device>
First, the configuration of the semiconductor light emitting device 1 will be described with reference to FIGS. 1 to 4. Here, FIG. 1 is a perspective view showing an outline of the overall configuration of the semiconductor light emitting device 1 according to the first embodiment. FIG. 2 is a plan view of the semiconductor light emitting device 1 of FIG. 3 is a cross-sectional view of the semiconductor light emitting device 1 taken along the line III-III in FIG. 4 is an enlarged view of a main part of the cross-sectional view shown in FIG. 1 to 4, one direction in the plan view of the semiconductor light emitting device 1 is defined as the X direction, a direction orthogonal to the X direction in the plan view is defined as the Y direction, and the height direction of the semiconductor light emitting device 1 is defined as the Z direction. To do.

  In the present embodiment, the semiconductor light emitting device 1 is a light source that emits pseudo white light. As shown in FIG. 1, the semiconductor light-emitting device 1 is a wiring board made of an alumina-based ceramic having excellent electrical insulation, good heat dissipation, and high reflectivity (preferably reflectivity of 80% or more). 2 is provided. On the chip mounting surface 2a of the wiring substrate 2, light emitting diode (LED: Light Emitting Diode) chips 3 that are a total of 20 semiconductor light emitting elements, 4 in the X direction and 5 in the Y direction, are arranged. Although not shown in FIG. 1, a wiring pattern for supplying power to each of these LED chips 3 is formed on the wiring board 2 to constitute an electric circuit.

  Note that the material of the wiring board 2 is not limited to alumina-based ceramics. For example, a material selected from resin, glass epoxy, a composite resin containing a filler in the resin, and the like as a material excellent in electrical insulation. You may form the main body of the wiring board 2 using. Alternatively, in order to improve the light reflectivity on the chip mounting surface 2a of the wiring board 2 and improve the light emission efficiency of the semiconductor light emitting device 1, silicone containing white pigment such as alumina powder, silica powder, magnesium oxide, titanium oxide or the like is used. It is preferable to use a resin. On the other hand, in order to obtain more excellent heat dissipation and reflectivity, the main body of the wiring board 2 may be made of metal such as silver. In such a case, it is necessary to electrically insulate the wiring pattern of the wiring board 2 from the metal body.

  Further, as shown in FIG. 1, on the chip mounting surface 2a of the wiring board 2 on which the LED chip 3 is mounted, at least part of incident light incident from the LED chip 3 is wavelength-converted to a different wavelength, and the wavelength conversion is performed. A wavelength conversion member 4 that emits the emitted light as emitted light to the outside of the semiconductor light emitting device 1 is disposed. The wavelength conversion member 4 has a plate shape and is disposed to face the 20 LED chips 3.

  Further, as shown in FIG. 3, the wavelength conversion member 4 is bonded to the wiring substrate 2 via a plurality of spacers 5. By interposing these spacers 5, as shown in FIG. 4, the wavelength conversion member 4. And a space between each LED chip 3.

  The gap provided here is provided with a distance L1 (see FIG. 4) calculated in advance so that the light emitted from the LED chip 3 reliably reaches the wavelength conversion member 4 at a position corresponding to the LED chip 3. ing. If the LED chip 3 is made as close as possible to the wavelength conversion member 4, the light emitted from the LED chip 3 will surely reach the wavelength conversion member 4, but the LED chip 3 is close to the wavelength conversion member 4. If it is too large, the wavelength conversion member 4 is heated by the heat generated by the LED chip 3, and the wavelength conversion function and the light emission efficiency may be reduced. For this reason, in order to prevent such an excessive temperature rise, it is preferable that the space | interval of the LED chip 3 and the wavelength conversion member 4 is 0.01 mm or more.

  If the semiconductor light emitting device 1 has a thermal margin, the first surface 4a of the wavelength conversion member 4 may be brought into close contact with the LED chip 3 without providing such a gap. Even when the LED chip 3 and the wavelength conversion member 4 are separated, the gap may be sealed with a translucent silicone resin, epoxy resin, glass, or the like. By doing in this way, the light from LED chip 3 can be guide | induced to the wavelength conversion member 4 efficiently.

  Hereinafter, the LED chip 3 and the wavelength conversion member 4 will be described in detail with reference to FIGS. 3 and 4.

(LED chip)
In this embodiment, the LED chip 3 is an LED chip that emits blue light having a peak wavelength of 460 nm. Specifically, as such an LED chip, for example, there is a GaN-based LED chip in which an InGaN semiconductor is used for a light emitting layer. Note that the type and emission wavelength characteristics of the LED chip 3 are not limited thereto, and various semiconductor light emitting elements such as LED chips can be used without departing from the gist of the present invention. In this embodiment, the peak wavelength of light emitted from the LED chip 3 is preferably in the wavelength range of 360 nm to 480 nm, and more preferably in the wavelength range of 390 nm to 430 nm or in the wavelength range of 430 nm to 480 nm.

  As shown in FIG. 4, a p-electrode 6 and an n-electrode 7 are provided on the surface of the LED chip 3 facing the wiring substrate 2 side. In the case of the LED chip 3 shown in FIG. 4, the p-electrode 6 is bonded to the wiring pattern 8 formed on the chip mounting surface 2a of the wiring board 2, and the wiring pattern 9 also formed on the chip mounting surface 2a is connected to the n. The electrode 7 is joined. The p electrode 6 and the n electrode 7 are connected to the wiring pattern 8 and the wiring pattern 9 by soldering via metal bumps (not shown). Other LED chips 3 not shown are also bonded to the wiring pattern formed on the chip mounting surface 2a of the wiring board 2 corresponding to each LED chip 3 in the same manner. Has been. Here, the LED chips 3 may be connected in series via the wiring pattern 8 and the wiring pattern 9, may be connected in parallel, and further connected in combination of series connection and parallel connection. Also good.

  The method of mounting the LED chip 3 on the wiring board 2 is not limited to this, and an appropriate method can be selected according to the type and structure of the LED chip 3. For example, after the LED chip 3 is bonded and fixed to a predetermined position of the wiring board 2, two electrodes of each LED chip 3 may be connected to a corresponding wiring pattern by wire bonding, or one electrode may be connected as described above. While joining to a corresponding wiring pattern, you may make it connect the other electrode to a corresponding wiring pattern by wire bonding.

(Wavelength conversion member)
As described above, the wavelength conversion member 4 converts the wavelength of part of the blue light emitted from the LED chip 3 and emits outgoing light having a wavelength different from that of the blue light. As a more specific configuration, as shown in FIGS. 1, 3, and 4, the wavelength conversion member 4 includes a transparent member 11 disposed at a position close to the LED chip 4, and an upper surface of the transparent member 11. And a filter 12 disposed so as to be laminated to each other.

  The transparent member 11 disperses the phosphor 11a, which absorbs and excites the blue light emitted from the LED chip 3 and emits outgoing light having a wavelength different from the incident light when returning to the ground state. And a resin 11 b that functions as a base material of the transparent member 11. FIG. 4 is an enlarged view of an essential part of a cross-sectional view of the semiconductor light emitting device 1 when a resin is used as a base material. In the wavelength conversion member 4 of FIG. 4, the phosphors 11a are dispersed in the resin 11b. doing. That is, the resin 11b as the base material holds the phosphor 11a in a dispersed manner.

  The phosphor 11a may be applied to the surface of the resin 11b without being dispersed and held in the resin 11b. In the present embodiment, the resin 11b as described above is used as the base material of the wavelength conversion member 4. However, the present invention is not limited to this, and glass or the like can also be used. Further, although the resin 11b holds only the phosphor 11a in a dispersed manner, the light diffusing material may also be held in a dispersed manner.

[Phosphor]
In this embodiment, since the LED chip 3 that emits blue light is used as a semiconductor light emitting element, as a method of obtaining white light from the semiconductor light emitting device 1, a part of the blue light is converted into red light and yellow light. A method is employed in which white light is synthesized by wavelength conversion and mixing of the red light and yellow light and blue light that has not been wavelength converted. Therefore, a red phosphor and a yellow phosphor that convert the wavelength of blue light into red light and yellow light are used for the phosphor 11a in the present embodiment.

  In addition, in order to adjust the chromaticity and color temperature of white light or improve color rendering, a part of the blue light may be wavelength-converted to green light. In this case, a green phosphor and a red phosphor can be used, a green phosphor and an orange phosphor can be used, or a yellow phosphor can be used in addition to the green phosphor and the red phosphor. Furthermore, in order to adjust the chromaticity and color temperature of white light or increase the light emission efficiency, a part of the blue light may be wavelength-converted only to yellow light. In this case, only a yellow phosphor may be used.

When a red phosphor is used, the emission peak wavelength is usually in the wavelength range of 550 nm or more, preferably 575 nm or more, more preferably 580 nm or more, and usually 780 nm or less, preferably 700 nm or less, more preferably 680 nm or less. Is preferred. Examples of such a red phosphor are, for example, CaAlSiN ₃ : Eu [CASN phosphor] described in JP-A-2006-008721 and JP-A-2008-7751 (Sr, Ca ) AlSiN ₃ : Eu [SCASN phosphor], Ca _1-x Al _1-x Si _{1 + x} N _3−x O _x : Eu [CASON phosphor] described in JP-A-2007-231245, etc. Eu-activated oxide, nitride or oxynitride phosphor, Mn-activated germanate phosphor such as 3.5MgO · 0.5MgF ₂ · GeO ₂ : Mn, Mn ⁴⁺ activated fluoride complex phosphor, etc. It is also possible to use.

The emission peak wavelength of a specific yellow phosphor is usually 530 nm or more, preferably 540 nm or more, more preferably 550 nm or more, and usually 620 nm or less, preferably 600 nm or less, more preferably 580 nm or less. Is preferred. Among them, as the yellow phosphor, for example, Y ₃ Al ₅ O ₁₂ : Ce [YAG phosphor], Lu ₃ Al ₅ O ₁₂ : Ce [LuAG phosphor], (Y, Gd) ₃ Al ₅ O ₁₂ : Ce, ( Sr, Ca, Ba, Mg) ₂ SiO ₄ : Eu, (Ca, Sr) Si ₂ N ₂ O ₂ : Eu, α-sialon, La ₃ Si ₆ N ₁₁ : Ce (provided that some of them are Ca or O Is optionally substituted).

In the case of using a green phosphor, the emission peak wavelength is usually larger than 500 nm, preferably 510 nm or more, more preferably 515 nm or more, and usually 550 nm or less, especially 540 nm or less, further 535 nm or less. It is preferable that If this emission peak wavelength is too short, it tends to be bluish, while if it is too long, it tends to be yellowish, and there is a possibility that the characteristics as green light will deteriorate. As such a green phosphor, for example, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce [G-YAG phosphor], described in International Publication No. 2007/091687 (Ba, Ca, Sr, Mg) ₂ SiO ₄ : Eu-activated alkaline earth silicate phosphor [BSS phosphor] represented by Eu, Si _6-z Al _z N _8-z O _z described in Japanese Patent No. 3912545 : Eu (provided that 0 <z ≦ 4.2), etc., Eu-activated oxynitride phosphor [β-SiAlON phosphor], M ₃ Si described in International Publication No. 2007/088966 Eu-activated oxynitride phosphor [BSON phosphor] such as ₆ O ₁₂ N ₂ : Eu (wherein M represents an alkaline earth metal element), BaMgAl described in JP-A-2008-274254 ₁₀ O ₁₇ : Eu, Mn activated aluminum It is also possible to use an acid salt phosphor [GBAM phosphor].

  The content of the phosphor 11a is preferably 0.1% by weight or more, more preferably 0.5% by weight or more, and further preferably 1% by weight or more in the total 100% by weight of the phosphor 11a and the resin 11b. On the other hand, 15 weight% or less is preferable and 10 weight% or less is more preferable.

〔resin〕
The resin 11b for dispersing and holding the phosphor 11a may be a crystalline resin or an amorphous resin. However, an amorphous resin is preferable, and an amorphous resin is thermosetting. Resin, thermoplastic resin, and photocurable resin are mentioned, and thermoplastic resin is preferable. As the thermosetting resin, for example, an epoxy resin and a silicone resin are preferably used.

  Examples of thermoplastic resins include polyethylene resins such as low, high density polyethylene, linear low density polyethylene, polypropylene resins, poly-3-methylbutene-1 resins, poly-4-methylpentene-1 resins, norbornene, etc. Polyolefin resins such as alicyclic polyolefin resins, including ethylene-vinyl acetate copolymers, copolymers of ethylene and methyl-, ethyl-, propyl-, and butyl-acrylates or methacrylates, ethylene-acrylic acid copolymer Ionomer resin such as coalescence; polystyrene resin, ABS resin, AS resin, AAS resin, AES resin, MBS resin and other styrene resins, polymethyl methacrylate, polymethacrylate and other acrylic resins; polyamide resin; polyacetal resin; polycarbonate Resin; Polyethylene Polyester resins such as phthalate resin, polybutylene terephthalate resin, polyethylene naphthalate resin, polylactic acid resin; modified polyphenylene ether resin; polyurethane resin; polyphenylene sulfide resin; polyarylate resin; polyether ether ketone resin; Resin: Fluorine containing polytetrafluoroethylene resin, tetrafluoroethylene and hexafluoropropylene copolymer, copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether, copolymer of ethylene and tetrafluoroethylene, polyvinylidene fluoride resin, etc. Resin etc. are mentioned, These 1 type, or 2 or more types of blend goods etc. are mentioned.

  The resin 11b preferably does not absorb light emitted from the semiconductor light emitting element (for example, ultraviolet light, near ultraviolet light, or blue light) or visible light emitted from the wavelength conversion member. Furthermore, it is preferable to have sufficient transparency and durability against blue light emitted from the LED chip 3.

  These resins used as the resin 11b described above may be used alone or in combination of two or more. Moreover, the copolymer of these resin may be sufficient and it may use it, laminating | stacking 2 or more types.

  Here, as the resin 11b, a polycarbonate resin can be most preferably used because it is excellent in transparency, heat resistance, mechanical properties, and flame retardancy. Hereinafter, the polycarbonate resin will be described in detail.

The polycarbonate resin used in the present invention is a polymer having a basic structure having a carbonic acid bond represented by the following general chemical formula (1).

In the chemical formula (1), X ¹ is generally a hydrocarbon, but X ¹ into which a hetero atom or a hetero bond is introduced may be used for imparting various properties.

  The polycarbonate resin can be classified into an aromatic polycarbonate resin in which carbon directly bonded to a carbonic acid bond is aromatic carbon and an aliphatic polycarbonate resin in which aliphatic carbon is aliphatic carbon, either of which can be used. Of these, aromatic polycarbonate resins are preferred from the viewpoints of heat resistance, mechanical properties, electrical characteristics, and the like.

  Although there is no restriction | limiting in the specific kind of polycarbonate resin, For example, the polycarbonate polymer formed by making a dihydroxy compound and a carbonate precursor react is mentioned. At this time, in addition to the dihydroxy compound and the carbonate precursor, a polyhydroxy compound or the like may be reacted. Further, a method of reacting carbon dioxide with a cyclic ether using a carbonate precursor may be used. The polycarbonate polymer may be linear or branched. Further, the polycarbonate polymer may be a homopolymer composed of one type of repeating unit or a copolymer having two or more types of repeating units. At this time, the copolymer can be selected from various copolymerization forms such as a random copolymer and a block copolymer. In general, such a polycarbonate polymer is a thermoplastic resin.

  Examples of aromatic dihydroxy compounds among monomers used as raw materials for aromatic polycarbonate resins include dihydroxy compounds such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene (ie, resorcinol), 1,4-dihydroxybenzene, and the like. Benzenes; dihydroxybiphenyls such as 2,5-dihydroxybiphenyl, 2,2′-dihydroxybiphenyl, 4,4′-dihydroxybiphenyl; 2,2′-dihydroxy-1,1′-binaphthyl, 1,2-dihydroxy Dihydroxynaphthalenes such as naphthalene, 1,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,7-dihydroxynaphthalene; 2 , 2'-di Droxydiphenyl ether, 3,3′-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,3′-dimethyldiphenyl ether, 1,4-bis (3-hydroxyphenoxy) benzene, 1, Dihydroxydiaryl ethers such as 3-bis (4-hydroxyphenoxy) benzene; 2,2-bis (4-hydroxyphenyl) propane (ie, bisphenol A), 1,1-bis (4-hydroxyphenyl) propane, 2 , 2-bis (3-methyl-4-hydroxyphenyl) propane, 2,2-bis (3-methoxy-4-hydroxyphenyl) propane, 2- (4-hydroxyphenyl) -2- (3-methoxy-4 -Hydroxyphenyl) propane, 1,1-bis (3-tert-butyl) 4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (3-cyclohexyl-4-hydroxyphenyl) propane, 2- (4- Hydroxyphenyl) -2- (3-cyclohexyl-4-hydroxyphenyl) propane, α, α′-bis (4-hydroxyphenyl) -1,4-diisopropylbenzene, 1,3-bis [2- (4-hydroxy Phenyl) -2-propyl] benzene, bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) cyclohexylmethane, bis (4-hydroxyphenyl) phenylmethane, bis (4-hydroxyphenyl) (4-propenylphenyl) ) Methane, bis (4-hydroxyphenyl) diphenylmethane, bis (4- Droxyphenyl) naphthylmethane, 1-bis (4-hydroxyphenyl) ethane, 2-bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1- Bis (4-hydroxyphenyl) -1-naphthylethane, 1-bis (4-hydroxyphenyl) butane, 2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) pentane, 1, 1-bis (4-hydroxyphenyl) hexane, 2,2-bis (4-hydroxyphenyl) hexane, 1-bis (4-hydroxyphenyl) octane, 2-bis (4-hydroxyphenyl) octane, 1-bis ( 4-hydroxyphenyl) hexane, 2-bis (4-hydroxyphenyl) hexane, 4,4-bis (4-hydro) Bis (hydroxyaryl) alkanes such as xylphenyl) heptane, 2,2-bis (4-hydroxyphenyl) nonane, 10-bis (4-hydroxyphenyl) decane, 1-bis (4-hydroxyphenyl) dodecane; Bis (4-hydroxyphenyl) cyclopentane, 1-bis (4-hydroxyphenyl) cyclohexane, 4-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3-dimethylcyclohexane 1-bis (4-hydroxyphenyl) -3,4-dimethylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3,5-dimethylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3 , 3,5-trimethylcyclohexane, 1,1-bis (4-hydroxy 3,5-dimethylphenyl) -3,3,5-trimethylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3-propyl-5-methylcyclohexane, 1,1-bis (4-hydroxyphenyl)- 3-tert-butyl-cyclohexane, 1,1-bis (4-hydroxyphenyl) -3-tert-butyl-cyclohexane, 1,1-bis (4-hydroxyphenyl) -3-phenylcyclohexane, 1,1-bis Bis (hydroxyaryl) cycloalkanes such as (4-hydroxyphenyl) -4-phenylcyclohexane; 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) Bisphenols containing cardo structure such as fluorene; 4,4'-dihydroxydiphenylsulfur Dihydroxy diaryl sulfides such as 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfide; 4,4′-dihydroxydiphenyl sulfoxide, 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfoxide, etc. Dihydroxydiaryl sulfoxides; dihydroxydiaryl sulfones such as 4,4′-dihydroxydiphenylsulfone and 4,4′-dihydroxy-3,3′-dimethyldiphenylsulfone;

  Among these, bis (hydroxyaryl) alkanes are preferable, and bis (4-hydroxyphenyl) alkanes are preferable, and 2,2-bis (4-hydroxyphenyl) propane (ie, from the viewpoint of impact resistance and heat resistance). Bisphenol A) is preferred.

  In addition, 1 type may be used for an aromatic dihydroxy compound and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of the monomer that is a raw material for the aliphatic polycarbonate resin include ethane-1,2-diol, propane-1,2-diol, propane-1,3-diol, 2,2-dimethylpropane-1, 3-diol, 2-methyl-2-propylpropane-1,3-diol, butane-1,4-diol, pentane-1,5-diol, hexane-1,6-diol, decane-1,10-diol Alkanediols such as cyclopentane-1,2-diol, cyclohexane-1,2-diol, cyclohexane-1,4-diol, 1,4-cyclohexanedimethanol, 4- (2-hydroxyethyl) cyclohexanol, Cycloalkanediols such as 2,2,4,4-tetramethyl-cyclobutane-1,3-diol; 2,2′-oxy Glycols such as sidiethanol (ie, ethylene glycol), diethylene glycol, triethylene glycol, propylene glycol, spiroglycol; 1,2-benzenedimethanol, 1,3-benzenedimethanol, 1,4-benzenedimethanol, 1 , 4-benzenediethanol, 1,3-bis (2-hydroxyethoxy) benzene, 1,4-bis (2-hydroxyethoxy) benzene, 2,3-bis (hydroxymethyl) naphthalene, 1,6-bis (hydroxy Ethoxy) naphthalene, 4,4′-biphenyldimethanol, 4,4′-biphenyldiethanol, 1,4-bis (2-hydroxyethoxy) biphenyl, bisphenol A bis (2-hydroxyethyl) ether, bisphenol S bis (2 -Hydroxyethyl) Aralkyl diols such as ether; 1,2-epoxyethane (ie, ethylene oxide), 1,2-epoxypropane (ie, propylene oxide), 1,2-epoxycyclopentane, 1,2-epoxycyclohexane, 1,4 -Cyclic ethers such as epoxycyclohexane, 1-methyl-1,2-epoxycyclohexane, 2,3-epoxynorbornane, 1,3-epoxypropane and the like may be used, and these may be used alone or in combination of two or more May be used in any combination and ratio.

  Among the monomers used as the raw material for the aromatic polycarbonate resin, examples of the carbonate precursor include carbonyl halide and carbonate ester. In addition, 1 type may be used for a carbonate precursor and it may use 2 or more types together by arbitrary combinations and a ratio.

  Specific examples of the carbonyl halide include phosgene, haloformates such as a bischloroformate of a dihydroxy compound, and a monochloroformate of a dihydroxy compound.

  Specific examples of the carbonate ester include diaryl carbonates such as diphenyl carbonate and ditolyl carbonate; dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; biscarbonate bodies of dihydroxy compounds, monocarbonate bodies of dihydroxy compounds, and cyclic carbonates. And carbonate bodies of dihydroxy compounds such as

  The method for producing the polycarbonate resin is not particularly limited, and any method can be adopted. Examples thereof include an interfacial polymerization method, a melt transesterification method, a pyridine method, a ring-opening polymerization method of a cyclic carbonate compound, and a solid phase transesterification method of a prepolymer. Hereinafter, the interfacial polymerization method and the melt transesterification method, which are particularly suitable among these methods, will be specifically described.

"Interfacial polymerization"
In the interfacial polymerization method, a dihydroxy compound and a carbonate precursor (preferably phosgene) are reacted in the presence of an organic solvent inert to the reaction and an aqueous alkaline solution, usually at a pH of 9 or higher. Polycarbonate resin is obtained by interfacial polymerization in the presence. In the reaction system, a molecular weight adjusting agent (terminal terminator) may be present as necessary, or an antioxidant may be present to prevent the oxidation of the dihydroxy compound.

  The dihydroxy compound and the carbonate precursor are as described above. Of the carbonate precursors, phosgene is preferably used, and a method using phosgene is particularly called a phosgene method.

  Examples of the organic solvent inert to the reaction include chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, chloroform, monochlorobenzene and dichlorobenzene; aromatic hydrocarbons such as benzene, toluene and xylene. . In addition, 1 type may be used for an organic solvent and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of the alkali compound contained in the alkaline aqueous solution include alkali metal compounds and alkaline earth metal compounds such as sodium hydroxide, potassium hydroxide, lithium hydroxide, and sodium hydrogen carbonate, among which sodium hydroxide and water Potassium oxide is preferred. In addition, 1 type may be used for an alkali compound and it may use 2 or more types together by arbitrary combinations and a ratio.

  Although there is no restriction | limiting in the density | concentration of the alkali compound in aqueous alkali solution, Usually, in order to control pH in the aqueous alkali solution of reaction to 10-12, it is used at 5 to 10 weight%. For example, when phosgene is blown, the molar ratio of the bisphenol compound and the alkali compound is usually 1: 1.9 or more in order to control the pH of the aqueous phase to be 10 to 12, preferably 10 to 11. Among these, it is preferable that the ratio is 1: 2.0 or more, usually 1: 3.2 or less, and more preferably 1: 2.5 or less.

  Examples of the polymerization catalyst include aliphatic tertiary amines such as trimethylamine, triethylamine, tributylamine, tripropylamine, and trihexylamine; alicyclic rings such as N, N′-dimethylcyclohexylamine and N, N′-diethylcyclohexylamine. Tertiary amines of formula; aromatic tertiary amines such as N, N′-dimethylaniline and N, N′-diethylaniline; quaternary ammonium salts such as trimethylbenzylammonium chloride, tetramethylammonium chloride and triethylbenzylammonium chloride; Examples include pyridine, guanine, guanidine salts, and the like. In addition, 1 type may be used for a polymerization catalyst and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of the molecular weight modifier include aromatic phenols having a monovalent phenolic hydroxyl group; aliphatic alcohols such as methanol and butanol, mercaptans, and phthalimides, among which aromatic phenols are preferred. Specific examples of such aromatic phenols include alkyl groups such as m-methylphenol, p-methylphenol, m-propylphenol, p-propylphenol, p-tert-butylphenol, and p-long chain alkyl-substituted phenol. Substituted phenols: Vinyl group-containing phenols such as isopropanyl phenol, epoxy group-containing phenols, carboxyl group-containing phenols such as o-oxine benzoic acid, 2-methyl-6-hydroxyphenylacetic acid, and the like. In addition, a molecular weight regulator may use 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  The usage-amount of a molecular weight modifier is 0.5 mol or more normally with respect to 100 mol of dihydroxy compounds, Preferably it is 1 mol or more, and is 50 mol or less normally, Preferably it is 30 mol or less. By making the usage-amount of a molecular weight modifier into this range, the thermal stability and hydrolysis resistance of a polycarbonate resin composition can be improved.

  In the reaction, the order of mixing the reaction substrate, reaction medium, catalyst, additive and the like is arbitrary as long as a desired polycarbonate resin is obtained, and an appropriate order may be arbitrarily set. For example, when phosgene is used as the carbonate precursor, the molecular weight regulator can be mixed at any time as long as it is between the reaction (phosgenation) of the dihydroxy compound and phosgene and the start of the polymerization reaction. In addition, reaction temperature is 0-40 degreeC normally, and reaction time is normally several minutes (for example, 10 minutes)-several hours (for example, 6 hours).

"Melted ester exchange method"
In the melt transesterification method, for example, a transesterification reaction between a carbonic acid diester and a dihydroxy compound is performed.

  The dihydroxy compound is as described above. On the other hand, examples of the carbonic acid diester include dialkyl carbonate compounds such as dimethyl carbonate, diethyl carbonate, and di-tert-butyl carbonate; diphenyl carbonate; substituted diphenyl carbonate such as ditolyl carbonate, and the like. Of these, diphenyl carbonate and substituted diphenyl carbonate are preferable, and diphenyl carbonate is particularly preferable. In addition, carbonic acid diester may use 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  The ratio of the dihydroxy compound and the carbonic acid diester is arbitrary as long as the desired polycarbonate resin can be obtained, but it is preferable to use an equimolar amount or more of the carbonic acid diester with respect to 1 mol of the dihydroxy compound. Is more preferable. The upper limit is usually 1.30 mol or less. By setting it as such a range, the amount of terminal hydroxyl groups can be adjusted to a suitable range.

  In the polycarbonate resin, the amount of terminal hydroxyl groups tends to have a great influence on thermal stability, hydrolysis stability, color tone and the like. For this reason, you may adjust the amount of terminal hydroxyl groups as needed by a well-known arbitrary method. In the transesterification reaction, a polycarbonate resin in which the terminal hydroxyl group amount is adjusted can be usually obtained by adjusting the mixing ratio of the carbonic acid diester and the aromatic dihydroxy compound, the degree of vacuum during the transesterification reaction, and the like. In addition, the molecular weight of the polycarbonate resin usually obtained can also be adjusted by this operation.

  When adjusting the amount of terminal hydroxyl groups by adjusting the mixing ratio of the carbonic acid diester and the dihydroxy compound, the mixing ratio is as described above. Further, as a more aggressive adjustment method, there may be mentioned a method in which a terminal terminator is mixed separately during the reaction. Examples of the terminal terminator at this time include monohydric phenols, monovalent carboxylic acids, carbonic acid diesters, and the like. In addition, 1 type may be used for a terminal terminator and it may use 2 or more types together by arbitrary combinations and a ratio.

  When producing a polycarbonate resin by the melt transesterification method, a transesterification catalyst is usually used. Any transesterification catalyst can be used. Among them, it is preferable to use, for example, an alkali metal compound and / or an alkaline earth metal compound. In addition, auxiliary compounds such as basic boron compounds, basic phosphorus compounds, basic ammonium compounds, and amine compounds may be used in combination. In addition, 1 type may be used for a transesterification catalyst and it may use 2 or more types together by arbitrary combinations and a ratio.

  In the melt transesterification method, the reaction temperature is usually 100 to 320 ° C. The pressure during the reaction is usually a reduced pressure condition of 2 mmHg or less. As a specific operation, a melt polycondensation reaction may be performed under the above-mentioned conditions while removing a by-product such as an aromatic hydroxy compound.

  The melt polycondensation reaction can be performed by either a batch method or a continuous method. When performing by a batch type, the order which mixes a reaction substrate, a reaction medium, a catalyst, an additive, etc. is arbitrary as long as a desired aromatic polycarbonate resin is obtained, What is necessary is just to set an appropriate order arbitrarily. However, considering the stability of the polycarbonate resin and the polycarbonate resin composition, the melt polycondensation reaction is preferably carried out continuously.

  In the melt transesterification method, a catalyst deactivator may be used as necessary. As the catalyst deactivator, a compound that neutralizes the transesterification catalyst can be arbitrarily used. Examples thereof include sulfur-containing acidic compounds and derivatives thereof. In addition, 1 type may be used for a catalyst deactivator and it may use 2 or more types together by arbitrary combinations and a ratio.

  The amount of the catalyst deactivator used is usually 0.5 equivalents or more, preferably 1 equivalent or more, and usually 10 equivalents or less, relative to the alkali metal or alkaline earth metal contained in the transesterification catalyst. Preferably it is 5 equivalents or less. Furthermore, it is 1 ppm or more normally with respect to aromatic polycarbonate resin, and is 100 ppm or less normally, Preferably it is 20 ppm or less.

  The molecular weight of the polycarbonate resin is arbitrary and may be appropriately selected and determined. The viscosity average molecular weight [Mv] converted from the solution viscosity is usually 10,000 or more, preferably 16,000 or more, more preferably 18, 000 or more, and usually 40,000 or less, preferably 30,000 or less. By setting the viscosity average molecular weight to be equal to or higher than the lower limit of the above range, the mechanical strength of the polycarbonate resin composition of the present invention can be further improved, which is more preferable when used for applications requiring high mechanical strength. On the other hand, by setting the viscosity average molecular weight to be equal to or lower than the upper limit of the above range, the polycarbonate resin composition of the present invention can be suppressed and improved in fluidity, and the molding processability can be improved and the molding process can be easily performed. Two or more types of polycarbonate resins having different viscosity average molecular weights may be mixed and used, and in this case, a polycarbonate resin having a viscosity average molecular weight outside the above-mentioned preferred range may be mixed.

The viscosity average molecular weight [Mv] is obtained by using methylene chloride as a solvent and obtaining an intrinsic viscosity [η] (unit: dl / g) at a temperature of 20 ° C. using an Ubbelohde viscometer. Η = 1.23 × 10 ⁻⁴ Mv ^0.83 . The intrinsic viscosity [η] is a value calculated by the following formula (1) by measuring the specific viscosity [η _sp ] at each solution concentration [C] (g / dl).

  The terminal hydroxyl group concentration of the polycarbonate resin is arbitrary and may be appropriately selected and determined, but is usually 1,000 ppm or less, preferably 800 ppm or less, more preferably 600 ppm or less. Thereby, the residence heat stability and color tone of the polycarbonate resin composition of the present invention can be further improved. Moreover, the minimum is 10 ppm or more normally, Preferably it is 30 ppm or more, More preferably, it is 40 ppm or more. Thereby, the fall of molecular weight can be suppressed and the mechanical characteristic of the polycarbonate resin composition of this invention can be improved more. The unit of the terminal hydroxyl group concentration is the weight of the terminal hydroxyl group expressed in ppm relative to the weight of the polycarbonate resin. The measurement method is colorimetric determination (method described in Macromol. Chem. 88 215 (1965)) by the titanium tetrachloride / acetic acid method.

  A polycarbonate resin may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  The polycarbonate resin is a polycarbonate resin alone (the polycarbonate resin alone is not limited to an embodiment containing only one type of polycarbonate resin, and is used in a sense including an embodiment containing a plurality of types of polycarbonate resins having different monomer compositions and molecular weights, for example. .), Or an alloy (mixture) of a polycarbonate resin and another thermoplastic resin may be used in combination. Further, for example, for the purpose of further improving flame retardancy and impact resistance, a polycarbonate resin is copolymerized with an oligomer or polymer having a siloxane structure; for the purpose of further improving thermal oxidation stability and flame retardancy A monomer, oligomer or polymer having a copolymer; a monomer, oligomer or polymer having a dihydroxyanthraquinone structure for the purpose of improving thermal oxidation stability; Copolymers with oligomers or polymers having an olefin-based structure; for the purpose of improving chemical resistance, they may be configured as copolymers mainly composed of polycarbonate resins, such as copolymers with polyester resin oligomers or polymers. . When used in combination with other thermoplastic resins, the proportion of the polycarbonate resin in the resin component is preferably 50% by weight or more, more preferably 60% by weight, and further preferably 70% by weight or more. preferable.

  Further, in order to improve the appearance of the molded product and improve the fluidity, the polycarbonate resin may contain a polycarbonate oligomer. The viscosity average molecular weight [Mv] of this polycarbonate oligomer is usually 1,500 or more, preferably 2,000 or more, and usually 9,500 or less, preferably 9,000 or less. Furthermore, the polycarbonate ligomer contained is preferably 30% by weight or less of the polycarbonate resin (including the polycarbonate oligomer).

  Further, the polycarbonate resin may be not only a virgin raw material but also a polycarbonate resin regenerated from a used product (so-called material-recycled polycarbonate resin). Examples of the used products include: optical recording media such as optical disks; light guide plates; vehicle window glass, vehicle headlamp lenses, windshields and other vehicle transparent members; water bottles and other containers; eyeglass lenses; Examples include architectural members such as glass windows and corrugated sheets. Also, non-conforming products, pulverized products obtained from sprues, runners, etc., or pellets obtained by melting them can be used.

  However, the regenerated polycarbonate resin is preferably 80% by weight or less, more preferably 50% by weight or less, among the polycarbonate resins contained in the polycarbonate resin composition of the present invention. Recycled polycarbonate resin is likely to have undergone deterioration such as heat deterioration and aging deterioration, so when such polycarbonate resin is used more than the above range, hue and mechanical properties can be reduced. It is because there is sex.

  The resin 11b described above can contain various known additives as necessary within a range not impairing the characteristics of the present invention. For example, light diffusing materials, heat stabilizers, antioxidants, mold release agents, flame retardants, flame retardant aids, UV absorbers, lubricants, light stabilizers, plasticizers, antistatic agents, thermal conductivity improvers, conductive Examples thereof include property improvers, colorants, impact resistance improvers, antibacterial agents, chemical resistance improvers, reinforcing agents, laser marking improvers, refractive index adjusters and the like. The specific kind and amount of these additives can be selected from known suitable ones for the resin 11b.

  Here, it illustrates about the preferable additive mix | blended with polycarbonate resin. The polycarbonate resin preferably contains a light diffusing material. By containing the light diffusing material, it becomes possible to impart light diffusibility to the base material. Examples of the light diffusing material include an inorganic light diffusing material, an organic light diffusing material, and bubbles.

  As the inorganic light diffusing material, for example, an inorganic light diffusing material containing elements such as silicon, aluminum, titanium, zirconium, calcium, magnesium, zinc, and barium can be used, and silicon, aluminum, It is preferable to use an inorganic light diffusing material containing at least one element of the group consisting of titanium and zirconium. As the organic light diffusing material, acrylic, styrene, polyamide, or an organic light diffusing material containing silicon or fluorine as an element can be used. Among them, an acrylic light diffusing material or silicon as an element can be used. It is preferable to use an organic light diffusing material containing.

  Specific examples of inorganic light diffusing materials include silicon dioxide (silica), white carbon, fused silica, talc, magnesium oxide, zinc oxide, titanium oxide, aluminum oxide, zirconium oxide, boron oxide, boron nitride, aluminum nitride, and nitride. Silicon, calcium carbonate, barium carbonate, magnesium carbonate, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, barium sulfate, calcium silicate, magnesium silicate, aluminum silicate, sodium silicate aluminide, zinc silicate, zinc sulfide, Examples of the material include glass particles, glass fibers, glass flakes, mica, wollastonite, zeolite, sepiolite, bentonite, montmorillonite, hydrotalcite, kaolin, and potassium titanate.

  These inorganic light diffusing materials may be treated with various surface treatment agents such as a silane coupling agent, a titanate coupling agent, methyl hydrogen polysiloxane, and a fatty acid-containing hydrocarbon compound. It may be coated with an active inorganic compound.

  Examples of the organic light diffusing material include materials such as a styrene (co) polymer, an acrylic (co) polymer, a siloxane (co) polymer, and a polyamide (co) polymer. Some or all of these molecules of the organic light diffusing material may or may not be crosslinked. Here, “(co) polymer” means both “polymer” and “copolymer”.

  The light diffusing material preferably contains at least one selected from the group consisting of silica, glass, calcium carbonate, mica, crosslinked acrylic (co) polymer particles, and siloxane (co) polymer particles. Further, the average particle diameter is preferably 1 μm or more, and preferably 30 μm or less. The average particle size is a particle size measured with an integrated weight percentage, a particle size distribution meter or the like.

  The content of the light diffusing material is usually 0.1 parts by weight or more, preferably 0.3 parts by weight or more with respect to 100 parts by weight of the polycarbonate resin. Further, it is usually contained in an amount of 40 parts by weight or less, preferably 30 parts by weight or less.

  Examples of the heat stabilizer include phosphorus compounds. Any known phosphorous compound can be used. Specific examples include phosphorus oxo acids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; acidic pyrophosphate metal salts such as acidic sodium pyrophosphate, acidic potassium pyrophosphate, and acidic calcium pyrophosphate; phosphoric acid Examples thereof include phosphates of Group 1 or Group 10 metals such as potassium, sodium phosphate, cesium phosphate, and zinc phosphate; organic phosphate compounds, organic phosphite compounds, and organic phosphonite compounds.

  Among them, triphenyl phosphite, tris (monononylphenyl) phosphite, tris (monononyl / dinonyl phenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, monooctyl diphenyl phosphite, Dioctyl monophenyl phosphite, monodecyl diphenyl phosphite, didecyl monophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) ) Organic phosphites such as octyl phosphite are preferred.

  The content of the heat stabilizer is usually 0.0001 parts by weight or more, preferably 0.001 parts by weight or more, more preferably 0.01 parts by weight or more with respect to 100 parts by weight of the polycarbonate resin. It is not more than parts by weight, preferably not more than 0.5 parts by weight, more preferably not more than 0.3 parts by weight, still more preferably not more than 0.1 parts by weight. If the amount of the heat stabilizer is too small, it is difficult to obtain the effect of improving the heat stability. If the amount is too large, the heat stability may be lowered.

  As antioxidant, a hindered phenolic antioxidant is mentioned, for example. Specific examples thereof include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl). ) Propionate, thiodiethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], N, N′-hexane-1,6-diylbis [3- (3,5-di-) tert-butyl-4-hydroxyphenylpropionamide), 2,4-dimethyl-6- (1-methylpentadecyl) phenol, diethyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl ] Methyl] phosphoate, 3,3 ′, 3 ″, 5,5 ′, 5 ″ -hexa-tert-butyl-a, a ′, a ''-(Mesitylene-2,4,6-triyl) tri-p-cresol, 4,6-bis (octylthiomethyl) -o-cresol, ethylenebis (oxyethylene) bis [3- (5-tert- Butyl-4-hydroxy-m-tolyl) propionate], hexamethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,3,5-tris (3,5- Di-tert-butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 2,6-di-tert-butyl-4- (4 6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol and the like.

  Among them, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate preferable.

  The content of the antioxidant is usually 0.0001 parts by weight or more, preferably 0.01 parts by weight or more, and usually 1 part by weight or less, preferably 0.5 parts by weight with respect to 100 parts by weight of the polycarbonate resin. Part or less, more preferably 0.3 part by weight or less. When the content of the antioxidant is less than the lower limit of the range, the effect as an antioxidant may be insufficient, and when the content of the antioxidant exceeds the upper limit of the range, There is a possibility that the effect reaches its peak and is not economical.

  Examples of the release agent include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, polysiloxane silicone oils, and the like.

  Examples of the aliphatic carboxylic acid include saturated or unsaturated aliphatic monovalent, divalent or trivalent carboxylic acid. Here, the aliphatic carboxylic acid includes alicyclic carboxylic acid. Among these, preferable aliphatic carboxylic acids are monovalent or divalent carboxylic acids having 6 to 36 carbon atoms, and aliphatic saturated monovalent carboxylic acids having 6 to 36 carbon atoms are more preferable. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, mellicic acid, tetrariacontanoic acid, montanic acid, adipine Examples include acids and azelaic acid.

  As aliphatic carboxylic acid in ester of aliphatic carboxylic acid and alcohol, the same thing as the said aliphatic carboxylic acid can be used, for example. On the other hand, examples of the alcohol include saturated or unsaturated monohydric or polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, a monovalent or polyvalent saturated alcohol having 30 or less carbon atoms is preferable, and an aliphatic or alicyclic saturated monohydric alcohol or aliphatic saturated polyhydric alcohol having 30 or less carbon atoms is more preferable.

  Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol, and the like. Is mentioned.

  Specific examples of esters of aliphatic carboxylic acids and alcohols include beeswax (a mixture based on myricyl palmitate), stearyl stearate, behenyl behenate, stearyl behenate, glycerin monopalmitate, glycerin monostearate Examples thereof include rate, glycerol distearate, glycerol tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate and the like.

  Examples of the aliphatic hydrocarbon compound having a number average molecular weight of 200 to 15,000 include liquid paraffin, paraffin wax, microwax, polyethylene wax, Fischer-Tropsch wax, and α-olefin oligomer having 3 to 12 carbon atoms. . Here, the aliphatic hydrocarbon includes alicyclic hydrocarbons.

  Among these, paraffin wax, polyethylene wax, or a partial oxide of polyethylene wax is preferable, and paraffin wax and polyethylene wax are more preferable.

  The number average molecular weight of the aliphatic hydrocarbon is preferably 5,000 or less.

  Examples of the polysiloxane silicone oil include dimethyl silicone oil, phenylmethyl silicone oil, diphenyl silicone oil, and fluorinated alkyl silicone.

  The content of the release agent is usually 0.001 part by weight or more, preferably 0.01 part by weight or more, and usually 5 parts by weight or less, preferably 3 parts by weight or less, relative to 100 parts by weight of the polycarbonate resin. More preferably, it is 1 part by weight or less, and still more preferably 0.5 part by weight or less. When the content of the release agent is less than the lower limit of the range, the effect of releasability may not be sufficient, and when the content of the release agent exceeds the upper limit of the range, hydrolysis resistance And mold contamination during injection molding may occur.

  Examples of the flame retardant include halogen-based, phosphorus-based, organic acid metal salt-based, and silicone-based flame retardants, and examples of the flame retardant auxiliary include fluororesin-based flame retardant auxiliary. A flame retardant and a flame retardant aid can be used in combination, or a plurality of flame retardants can be used in combination. Among these, phosphorus flame retardants, organic acid metal salt flame retardants, and fluororesin flame retardant aids are preferred.

  Examples of phosphorus flame retardants include aromatic phosphate esters and phosphazene compounds. As the organic acid metal salt flame retardant, an organic sulfonic acid metal salt is preferable, and a fluorine-containing organic sulfonic acid metal salt is particularly preferable. Specific examples thereof include potassium perfluorobutane sulfonate. As the fluorine-based flame retardant aid, a fluoroolefin resin is preferable, and a tetrafluoroethylene resin having a fibril structure can be exemplified. The fluorine-based flame retardant aid may be in a powder form, a dispersion form, a powder form in which a fluororesin is coated with another resin, or any form.

  The blending ratio of these flame retardants and flame retardant aids may be blended in the amount necessary to achieve the desired flame retardant level, but is usually in the case of phosphorus flame retardants relative to 100 parts by weight of polycarbonate. It is preferably blended in the range of 1 to 20 parts by weight, in the case of organic acid metal salts in the range of 0.01 to 1 parts by weight, and in the case of fluororesin-based flame retardant aids in the range of 0.01 to 1 part by weight. . Within the above range, one or more flame retardants and flame retardant aids can be used. If the amount is less than this range, it is difficult to improve the flame retardancy. If the amount is more than this range, the thermal stability and mechanical properties tend to decrease, which is not preferable. The flame retardant level can be determined by, for example, a combustion test typified by UL94.

  Examples of the ultraviolet absorber include inorganic ultraviolet absorbers such as cerium oxide and zinc oxide; organics such as benzotriazole compounds, benzophenone compounds, salicylate compounds, cyanoacrylate compounds, triazine compounds, oxanilide compounds, malonic ester compounds, hindered amine compounds, etc. Examples include ultraviolet absorbers. Of these, organic ultraviolet absorbers are preferred, and benzotriazole compounds are more preferred. By selecting an organic ultraviolet absorber, the polycarbonate resin composition of the present invention tends to have good transparency and mechanical properties.

  Specific examples of the benzotriazole compound include, for example, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- [2′-hydroxy-3 ′, 5′-bis (α, α-dimethylbenzyl). ) Phenyl] -benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butyl-phenyl) -benzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5 ′) -Methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butyl-phenyl) -5-chlorobenzotriazole), 2- (2'-hydroxy-3 ', 5'-di-tert-amyl) -benzotriazole, 2- (2'-hydroxy-5'-tert-octylphenyl) benzotriazole, 2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol] and the like, among others, 2- (2′- Hydroxy-5'-tert-octylphenyl) benzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol] And 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole is particularly preferable.

  Specific examples of such benzotriazole compounds include “Seesorb 701”, “Seesorb 702”, “Seesorb 703”, “Seesorb 704”, and “Seesorb 705” manufactured by Sipro Kasei Co., Ltd. (trade names, the same applies hereinafter). , “Seasorb 709”, “Biosorb 520”, “Biosorb 580”, “Biosorb 582”, “Biosorb 583” manufactured by Kyodo Yakuhin Co., Ltd. “UV5411”, “LA-32”, “LA-38”, “LA-36”, “LA-34”, “LA-31”, manufactured by Adeka Corporation, “Tinuvin P”, “Cinuvin” manufactured by Ciba Specialty Chemicals 234 "," Tinubin 326 "," Tinubin 327 "," Tinubin 3 8 ", and the like.

  The preferable content of the ultraviolet absorber is 0.01 parts by weight or more, more preferably 0.1 parts by weight or more, and 5 parts by weight or less, preferably 3 parts by weight or less with respect to 100 parts by weight of the polycarbonate resin. More preferably, it is 1 part by weight or less, and still more preferably 0.5 part by weight or less. If the content of the ultraviolet absorber is less than the lower limit of the range, the effect of improving the weather resistance may be insufficient, and if the content of the ultraviolet absorber exceeds the upper limit of the range, the mold Debogit etc. may occur and cause mold contamination. In addition, 1 type may contain the ultraviolet absorber and 2 or more types may contain it by arbitrary combinations and a ratio.

"Manufacturing method of transparent member 11"
The manufacturing method of the transparent member 11 which comprises the wavelength conversion member 4, and the processing method of the wavelength conversion member 4 are not specifically limited, What is necessary is just to use a well-known method as a processing method of resin 11b. For example, the general manufacturing method of the transparent member 11 when the resin 11b is a polycarbonate resin is as follows.

  The phosphor 11a and other components blended as necessary are added to the polycarbonate resin used as the resin 11b, and mixed with various mixers such as a tumbler mixer and a Henschel mixer. Mixing may be performed by mixing all raw materials at once, or by dividing several raw materials and mixing them. Thereafter, it is melt-kneaded with a Banbury mixer, roll, Brabender, single-screw kneading extruder, twin-screw kneading extruder, kneader or the like to obtain resin composition pellets.

  Using the obtained resin composition pellets, required by any molding method such as sheet / film extrusion molding, profile extrusion molding, vacuum molding, injection molding, blow molding, injection blow molding, rotational molding, foam molding, etc. The transparent member 11 having a shape is formed. Among these, it is preferable to adopt an injection molding method. Furthermore, if necessary, the molded body can be further processed by welding, bonding, cutting, and the like.

  The case where the resin 11b is a polycarbonate resin and a light diffusing material is mixed will be illustrated in more detail and preferable conditions.

  The polycarbonate resin, the phosphor 11a, the light diffusing material, and other additives are mixed with a tumbler mixer, and then melt-kneaded using a single screw or twin screw extruder. As a melt-kneading condition, a screw composed mainly of a forward-flight flight screw element is used as a screw so as not to apply excessive pruning force. The frequent use of a screw element that strongly applies a cutting force, such as a reverse feed flight screw or a kneading screw element, is undesirable because it causes discoloration of the resin. In addition, when the phosphor 11a is hard, it is preferable to use a screw and cylinder made of a material that has been subjected to an abrasion-resistant treatment that is difficult to cut.

  The kneading temperature is preferably in the range of 230 to 340 ° C. If the measured resin temperature exceeds 340 ° C., discoloration tends to occur, which is not preferable. If the resin temperature is less than 230 ° C., the melt viscosity of the polycarbonate resin is too high, and the mechanical load on the extruder increases. A particularly preferable kneading temperature is in the range of 240 to 300 ° C.

  What is necessary is just to select a screw rotation speed and discharge amount suitably in view of the production speed, the load to an extruder, and the state of a resin pellet. Moreover, it is preferable to install one or more vent structures in the extruder for releasing air entrained with the raw material and gas generated by heating out of the extruder system.

  What is necessary is just to shape | mold and process into a desired shape by arbitrary processing methods using the polycarbonate resin composition pellet obtained by the above.

〔filter〕
In this embodiment, the filter 12 has a structure in which a plurality of dielectric thin films (that is, dielectric multilayer films) having different refractive indexes are laminated on a substrate such as glass. For example, the dielectric multilayer film has a structure in which a plurality of SiO ₂ and ZrO ₂ are alternately laminated on a glass substrate. Since it has such a laminated structure, the filter 12 can control the wavelength selectivity of reflectance / transmittance by utilizing the light interference effect. That is, the reflectivity / transmittance of the filter 12 changes depending on the wavelength of incident light, and the reflectivity / transmittance also changes depending on the incident angle.

  Note that the characteristics (light transmittance) of the filter 12 will be described in detail when the evaluation results by simulation described later are described.

In this embodiment, the filter 12 including the dielectric multilayer film is formed by alternately laminating a plurality of dielectric thin films SiO ₂ and ZrO ₂ , but the material for forming the filter 12 is limited to these. There is nothing. For example, the filter 12 may be formed by a resin laminate in which thin films made of resins having different refractive indexes are laminated, or the filter 12 is formed by an inorganic crystal laminate in which thin films made of inorganic crystals having different refractive indexes are laminated. May be.

  Therefore, the wavelength conversion member 4 of the present embodiment has an incident surface for blue light emitted from the LED chip 3 because of the arrangement relationship of the LED chip 3, the transparent member 11, and the filter 12 as described above, and the laminated structure of the filter 12. From the side, the transparent member 11 (that is, the phosphor 11a and the resin 11b), glass, and a dielectric multilayer film are sequentially laminated.

  In the wavelength conversion member 4 of the present embodiment, the filter 12 as described above is laminated on the transparent member 11 containing the phosphor 11a, and the filter 12 is positioned on the light emitting surface side of the wavelength conversion member 4. . For this reason, when the semiconductor light emitting device 1 or the wavelength conversion member 4 is viewed from the light emitting surface side of the wavelength conversion member 4 when no light is emitted, the color of the wavelength conversion member 4 and the body color of the filter 12 are visually recognized. Will be. Here, since the color obtained by combining the body color of the wavelength conversion member 4 and the body color of the filter 12 is a natural color (for example, white) than the body color of the wavelength conversion member 4 itself, the filter according to the present embodiment. By providing 12, the body color improvement effect of the wavelength conversion member 4 and the semiconductor light emitting device 1 is exhibited.

  The semiconductor light emitting device 1 of this example having the above-described configuration can be used as general illumination. In such a case, the light emitted from the semiconductor light emitting device 1 (specifically, white light that is a combined light of blue light, red light, and yellow light or green light) has a deviation duv of −0 from the black body radiation locus. It is preferably 0.0200 to 0.0200, and the color temperature is preferably in the range of 1,600K to 7,000K.

  Further, the semiconductor light emitting device 1 of the present embodiment having the above-described configuration can be used as a backlight in addition to general illumination. When used as an LED light source for a backlight of a display, light emitted from the semiconductor light-emitting device 1 (specifically, blue light, red light, and white light that is a combined light of yellow light or green light) is usually colored. The temperature is in the range of 5,000K to 20,000K.

<Evaluation of wavelength conversion member by simulation>
Next, a plurality of types of filters 12 having different laminated structures were evaluated by simulation. More specifically, the wavelength dependence of the transmittance at an incident angle of 0 degree for four types of filters 12 in which the number of laminated layers of two types of dielectric thin films (SiO ₂ and ZrO ₂ ) having different refractive indexes is changed. The incident angle dependency of the transmittance for light having a wavelength of 450 nm and the incident angle dependency of the transmittance for light having a wavelength of 600 nm were evaluated by simulation.

  As specific four types of filters 12, sample filters a, b, c, and d having a laminated structure as shown in Table 1 below were assumed.

As shown in Table 1, the sample filter a has a structure in which a dielectric thin film made of ZrO ₂ and a dielectric thin film made of SiO ₂ are alternately laminated 27 times in total on a glass substrate. The film thickness of ZrO ₂ immediately above and away from the substrate is 11.00 nm, and the film thickness of the other ZrO ₂ is 46.20 nm. On the other hand, the thickness of SiO ₂ located closest to the substrate and the thickness of SiO ₂ farthest from the substrate is 90.20 nm, and the thickness of the other SiO ₂ is 70.95 nm. That is, the sample filter a is a laminate in which thin ZrO ₂ and thick SiO ₂ are located at both end portions in the thickness direction, and thick ZrO ₂ and thin SiO ₂ are located so as to be sandwiched between the thin ZrO ₂ and thick SiO _2. It has a structure.

Further, as shown in Table 1, the sample filter b has a structure in which a dielectric thin film made of ZrO ₂ and a dielectric thin film made of SiO ₂ are alternately laminated on a glass substrate 13 times in total. . As with the sample filter a, the film thickness of ZrO ₂ immediately above and away from the substrate is 11.00 nm, and the film thickness of the other ZrO ₂ is 46.20 nm. Similarly to the sample filter a, the thickness of SiO ₂ located closest to the substrate and the thickness of SiO ₂ farthest from the substrate is 90.20 nm, and the thickness of the other SiO ₂ is 70.95 nm. That is, the sample filter b as with the sample filter a is located is thin ZrO ₂ and thick SiO ₂ on both end portions in the thickness direction, the thin ZrO ₂ and thick so as to be interposed SiO ₂ thick ZrO ₂ and thin SiO ₂ Has a laminated structure in which is located.

Furthermore, as shown in Table 1, the sample filter c has a structure in which a dielectric thin film made of ZrO ₂ and a dielectric thin film made of SiO ₂ are alternately laminated a total of seven times on a glass substrate. . Similar to the sample filter a and the sample filter b, the film thickness of ZrO ₂ immediately above and away from the substrate is 11.00 nm, and the film thickness of the other ZrO ₂ is 46.20 nm. On the other hand, the thickness of SiO ₂ located closest to the substrate and the thickness of SiO ₂ farthest from the substrate is 90.20 nm, and the thickness of SiO ₂ located in the center is 70.95 nm. That is, the sample filter c Like the sample filter a and the sample filter b is located is thin ZrO ₂ and thick SiO ₂ on both end portions in the thickness direction, the thin ZrO ₂ and thick thick ZrO ₂ be sandwiched between SiO ₂ And a laminated structure in which thin SiO ₂ is located.

As shown in Table 1, the sample filter d has a structure in which a dielectric thin film made of ZrO ₂ and a dielectric thin film made of SiO ₂ are alternately laminated a total of five times on a glass substrate. . The film thickness of ZrO ₂ immediately above and away from the substrate is 11.00 nm, and the film thickness of ZrO ₂ located in the center is 46.20 nm. On the other hand, the film thickness of SiO ₂ is 90.20 nm. That is, the sample filter d has a laminated structure in which thin ZrO ₂ is located at both end portions in the thickness direction, and thick ZrO ₂ and SiO ₂ are located so as to be sandwiched between the thin ZrO ₂ .

  The substrate made of glass in the sample filters a to d was assumed to be Corning non-acrylic glass (# 1737).

  Next, with reference to FIG. 5 and Table 2 below, the evaluation results of the wavelength dependence of the transmittance of each sample filter at an incident angle of 0 degree will be described. In FIG. 5, the horizontal axis represents the wavelength (nm), and the vertical axis represents the light transmittance at an incident angle of 0 degree. Here, the incident angle of 0 degrees is a direction perpendicular to the main surfaces (exposed surfaces of the dielectric multilayer film) of the sample filters a to d. Table 2 shows numerical data of each filter in FIG.

  As can be seen from FIG. 5 and Table 2, the sample filters a to d do not transmit light (blue light) having a wavelength of 330 nm to 525 nm, but have other wavelengths (red light, etc.), although the transmittance is different. ). More specifically, the sample filter a has a light transmittance of 0 to 470 nm (0%: does not transmit, that is, reflects 100%), and the sample filter a blocks light of the wavelength well. I found out (reflective). Further, it has been found that the sample filter b can also block light with the wavelength relatively well, although the sample filter b cannot completely block light with a wavelength of 370 nm to 470 nm, unlike the sample filter a. On the other hand, the sample filter c does not transmit light having a wavelength of 330 nm to 525 nm as compared with light of other wavelengths, but has a light blocking rate (that is, reflectance) of about 1/0 compared to the sample filter a. It turned out that it has fallen to 3 or less. As a specific numerical value, the transmittance of the sample filter c was 0.25 (25%) or more in the wavelength range of 330 nm to 525 nm. Furthermore, it was found that the sample filter d had a light blocking rate that was reduced to about ½ or less compared to the sample filter a. Specifically, the transmittance of the sample filter d was 0.45 (45%) or more in the wavelength range of 330 nm to 525 nm.

The reason for this result is that the film thickness of the sample filter a and the sample filter b is larger than the film thickness of the sample filter c and the sample filter d, and more dielectric thin films are laminated. In other words, the laminated structure of ZrO ₂ and SiO ₂ can block light having a wavelength of 330 nm to 525 nm at an incident angle of 0 degree, and the multilayer (multilayer) of the laminated layer can cut off the blocking rate (reflectance). It is possible to improve.

  From the results shown in FIG. 5 and Table 2, the sample filter a and the sample filter b are suitable as general filters that accurately block light of a certain wavelength, and the characteristics of the sample filter c and the sample filter d are related to the general filter. It turned out to be inferior to the characteristics of a typical filter.

  Next, with reference to FIG. 6 and Table 3 below, the evaluation result of the incident angle dependency of the transmittance with respect to light having a wavelength of 450 nm (blue light: first visible light) will be described. In FIG. 6, the horizontal axis represents the incident angle (degrees), and the vertical axis represents the transmittance. Here, as in the case of FIG. 5, the incident angle of 0 degrees is a direction perpendicular to the main surfaces (exposed surfaces of the dielectric multilayer film) of the sample filters a to d. Table 3 shows numerical data of each filter in FIG.

  As can be seen from FIG. 6 and Table 3, it was found that the sample filter a satisfactorily blocked light having a wavelength of 450 nm at an incident angle of 0 degree to an incident angle of 30 degrees. In the sample filter a, the transmittance sharply increases when the incident angle exceeds 30 degrees, reaches the transmittance peak at the incident angle of 60 degrees, and decreases when the incident angle exceeds 60 degrees. The sample filter b has the same characteristics as the sample filter a. More specifically, the sample filter b well blocks light having a wavelength of 450 nm at an incident angle of 0 degrees to an incident angle of 30 degrees (specifically, The transmittance is 0.20 (20%) or less), and when the incident angle exceeds 30 degrees, the transmittance increases sharply, and the transmittance reaches a peak at an incident angle of 60 degrees, and the incident angle is 60 degrees. If it exceeds, the transmittance decreases. That is, it was found that the sample filter b also satisfactorily blocked light having a wavelength of 450 nm at an incident angle of 0 degree to an incident angle of 30 degrees.

  On the other hand, in the sample filter c, the transmittance at an incident angle of 0 degree is 0.40 (40%), and the transmittance gradually increases as the incident angle increases in the range of the incident angle from 0 degree to 60 degrees, The transmittance peaked at an incident angle of 60 degrees, and the transmittance decreased when the incident angle exceeded 60 degrees. More specifically, the sample filter c transmits about half of the light having a wavelength of 450 nm and reflects the remaining half of the light in the range of the incident angle of 0 to 40 degrees, and the incident angle of 40 to 70 degrees. It was found that in the range of degrees, it transmits about 60% or more of light having a wavelength of 450 nm. Further, in the sample filter d, the transmittance at an incident angle of 0 degree is about 0.65 (65%), and the transmittance gradually increases as the incident angle increases in the range of the incident angle from 0 degree to 60 degrees. The transmittance peaked at an incident angle of 60 degrees, and the transmittance decreased when the incident angle exceeded 60 degrees. More specifically, the sample filter d transmits about 0.70 (70%) of light having a wavelength of 450 nm and the remaining about 0.30 (30%) in an incident angle range of 0 to 70 degrees. Was found to reflect.

  As a result common to the sample filters a to d, the transmittance at an incident angle of 60 degrees was about 0.80 (80%), and the transmittance was the peak value during the simulation. Further, when the incident angle exceeded 60 degrees, the transmittance similarly decreased, and the transmittance at each incident angle was substantially the same value. Specifically, the transmittance was about 0.70 (70%) at an incident angle of 70 degrees, and the transmittance was about 0.45 (45%) at an incident angle of 80 degrees.

  Next, referring to FIG. 7 and Table 4, the evaluation result of the incident angle dependency of the average transmittance for light having a wavelength of 500 to 700 nm (red light: second visible light) will be described. In FIG. 7, the horizontal axis is the incident angle (degrees), and the vertical axis is the transmittance. Here, the incident angle of 0 degrees is defined as a direction perpendicular to the main surfaces (exposed surfaces of the dielectric multilayer film) of the sample filters a to d as in the case of FIGS. Table 4 shows numerical data of each filter in FIG.

  As can be seen from FIG. 7 and Table 4, it was found that the characteristics of the average transmittance of the sample filters a to d with respect to light having a wavelength of 500 to 700 nm are common. More specifically, the average transmittance is about 0.90 (90%) at an incident angle of 0 to 40 degrees, and the value is substantially maintained. When the incident angle exceeded 40 degrees, the average transmittance gradually decreased, and the average transmittance was about 0.85 (85%) at an incident angle of 60 degrees. Further, when the incident angle exceeded 60 degrees, the average transmittance decreased sharply, and the transmittance was about 0.46 (46%) at an incident angle of 80 degrees.

  From the results shown in FIG. 7 and Table 4, it was found that the difference in the laminated structure of the sample filters a to d does not affect the change in average transmittance with respect to light having a wavelength of 500 to 700 nm. In other words, the sample filters a to d have a common transmission characteristic with respect to light having a wavelength of 600 nm, and light having a wavelength of 500 to 700 nm due to the difference in the laminated structure of the sample filters a to d. It is considered that the dependence of the average transmittance on the incident angle does not differ greatly.

<Evaluation of semiconductor light-emitting device by simulation>
Next, a semiconductor light emitting device 1 having a wavelength conversion member 4 including any of the sample filters a to d described above, and a semiconductor light emitting device having a wavelength conversion member not including a filter 12 (that is, a conventional semiconductor light emitting device). Evaluation of emission phosphor reduction was performed. Hereinafter, the semiconductor device 1 on which the sample filter a is mounted is referred to as a sample device A, the semiconductor device 1 on which the sample filter b is mounted is referred to as a sample device B, and the semiconductor device 1 on which the sample filter c is mounted is referred to as a sample device C. The semiconductor device 1 on which the sample filter d is mounted is referred to as a sample device D, and the semiconductor light emitting device having a wavelength conversion member that does not include the filter 12 is referred to as a sample device E. In this simulation, the dimensions (X direction and Y direction) of each sample device were 5 cm × 5 cm, and the thickness was 1 mm. Here, the wavelength conversion member in each sample device has a structure in which a transparent member (that is, phosphor and resin), glass, and a dielectric multilayer film are sequentially laminated from the incident surface side of the blue light emitted from the LED chip. Have.

  First, the average transmittance of blue light (wavelength: 430 nm to 480 nm) in the transparent member 11 assumed in this simulation will be described with reference to FIG. 8 and Table 5 below. FIG. 8 is a graph showing a calculation result of the transmittance of the blue light for each incident angle with respect to the transparent member 11, the horizontal axis is the incident angle (degree), and the vertical axis is the transmittance of the blue light. Table 5 shows numerical data of FIG.

  As shown in FIG. 8 and Table 5, the transparent member 11 constituting the wavelength conversion member 4 has a reduced blue light transmittance as the incident angle (that is, the viewing angle) increases. That is, when blue light is incident on the transparent member 11, more blue light is transmitted through the transparent member 11 without being wavelength-converted in the direction immediately above the oblique direction. In particular, the average transmittance of blue light at an incident angle of 0 degrees is about 20% larger than the average transmittance of blue light at an incident angle of 45 degrees.

  Next, as a specific evaluation, when applying a forward current of 240 mA and a forward voltage of 15.1 V to the sample devices A to E, the color temperature of 4000 K of the synthesized white light emitted is made the same. The required phosphor concentration and luminous efficiency were calculated by simulation and evaluated. Here, the phosphor concentration is a ratio of the phosphor 11a in the transparent member 11, and the unit is a weight percent concentration (wt%). The luminous efficiency of each sample device is shown as a relative value with the luminous efficiency of the sample device E as 100. Table 5 below shows the phosphor concentration and luminous efficiency used in each sample device.

  As can be seen from Table 6, it was found that the sample devices A to D equipped with the filter 12 had a smaller phosphor concentration value than the sample device E which is a conventional semiconductor light emitting device. That is, in the sample apparatuses A to D, the phosphor usage is maintained at 95% or more compared to the initial case where the filter 12 is not used (30% or more in the sample apparatuses A and B). And the cost of the wavelength conversion member 4 and the semiconductor light emitting device 1 can be reduced. In addition, the sample devices A to D equipped with the filter 12 maintain the light emission efficiency at 95% or more as compared with the sample device E which is a conventional semiconductor light emitting device, and the reduction is suppressed to a low level. It is possible that

  In particular, in the sample apparatus A and the sample apparatus B, it has been found that the phosphor concentration can be reduced by about 40% compared to the sample apparatus E which is a conventional semiconductor light emitting apparatus. This is because the average transmittance of blue light in an incident angle range of 0 to 30 degrees is 20% or less, so that the blue light that has once passed through the transparent member 11 is reflected by the filter 12 and guided again to the transparent member. This is because the wavelength is converted by the phosphor 11a after the light is emitted, and the blue light can be sufficiently wavelength-converted to light of other wavelengths (red light and yellow light) even with a small amount of the phosphor 11a. In addition, since the average value of the transmittance of red light in the range of incident angles from 0 degrees to 30 degrees is 80% or less, the wavelength-converted light can be accurately emitted from the exit surface side. This is because it is considered that white light is efficiently synthesized using the generated light.

  As can be seen from the evaluation results of the sample devices A to E described above, the semiconductor light emitting device capable of reducing the usage amount of the phosphor 11a and sufficiently reducing the cost becomes the sample device A and the sample device B. The laminated structure is preferably the same as that of the sample a or the sample b. In view of the above, the filter 12 has an average transmittance of 20% or less of blue light in an incident angle range of 0 to 30 degrees, and transmits red light in an incident angle range of 0 to 30 degrees. It is important that the average value of the rate has a characteristic of 80% or more. This is because the blue light emitted from the LED chip 4 is not wavelength-converted and the transparent member 11 and the filter 12 (that is, when the average transmittance of blue light in the range of incident angles of 0 to 30 degrees exceeds 20% (that is, The wavelength conversion member 4) passes through, the conversion efficiency of the wavelength conversion member 4 decreases, and a predetermined amount of light (for example, red light and yellow light) required for the synthetic white light is emitted. This is because the amount of the phosphor 11a needs to be increased. Further, when the average value of the transmittance of red light in the range of incident angles from 0 degrees to 30 degrees is less than 80%, it becomes difficult to emit red light that is converted light, and a predetermined amount required for synthetic white light is reduced. This is because it is necessary to increase the amount of the phosphor 11a in order to emit red light. Here, the average transmittance of blue light is not only the transmittance of blue light of a specific wavelength (for example, 450 nm), but the average value of transmittance of all blue light in a general wavelength range. Show. The same applies to the average value of the transmittance of red light.

  In the filter 12, it is preferable that the average transmittance of blue light at an incident angle of 45 degrees is larger than the average transmittance of blue light at 0 degrees. This is because the average transmittance of blue light at an incident angle of 45 degrees and the average transmittance of blue light at an incident angle of 0 degrees are generally small in the transparent member 11 composed of a base material such as a resin 11b. This is because the angle dependency of the transmittance in the transparent member 11 is offset by the angle dependency of the transmittance in the filter 12. Thereby, in the synthetic white light emitted from the wavelength conversion member 11 and the semiconductor light emitting device 1, color unevenness that depends on the viewing direction is less likely to occur.

  Further, the filter 12 preferably has an average blue light transmittance increasing from an incident angle of 0 degrees to 50 degrees, and an average red light transmittance decreasing from an incident angle of 0 degrees to 50 degrees. . This is because, in the transparent member 11 made of a base material such as the resin 11b, the average transmittance of blue light decreases from an incident angle of 0 degrees to 50 degrees, and the average value of the transmittance of red light is the incident angle. It is common to increase from 0 degrees to 50 degrees in order to cancel out the angle dependency of blue light and the angle dependency of red light even in a wide viewing range.

  The filter 12 preferably has an average blue light transmittance of 50% or less and an average red light transmittance of 80% or more at an incident angle of 0 to 40 degrees. By setting in this way, excessive reflection of blue light necessary for the synthesis of white light is prevented, and even in a wide viewing range, color unevenness is prevented in the wide viewing range without causing shortage of blue light and red light. It is possible to achieve good white light synthesis while preventing the above. Note that the filter 12 of this embodiment does not transmit all of the incident blue light, but needs to transmit a part thereof (that is, the filter 12 functions as a blue cut filter). Even in this case, it is preferable that the average transmittance of blue light is less than 90% at an incident angle of 0 degree.

  As a more preferable value of the average transmittance of blue light at each incident angle, the average transmittance of blue light at an incident angle of 0 degrees is 20% or less. The average transmittance of blue light at an incident angle of 60 degrees is 60% or more. The reason why the average transmittance is set to 20% or less is that if the average transmittance exceeds 20%, the probability of wavelength conversion by the phosphor 11a decreases, and the usage amount of the phosphor 11a needs to be increased. is there. The reason why the average transmittance is set to 60% or more is to synthesize good white light while suppressing the shortage of blue light required for white light synthesis.

<Modification>
In the filter 12 of the embodiment described above, the average transmittance of blue light, which is visible light, is 20% or less in the range of incident angles from 0 degree to 30 degrees, and the average transmittance of red light, which is visible light, is 0 incident angle. Although it was 80% or more in the range of 30 degrees to 30 degrees, the characteristics may be reversed. That is, the average transmittance of blue light may be 80% or more in the range of incident angles from 0 degrees to 30 degrees, and the average transmittance of red light may be 20% or less in the range of incident angles from 0 degrees to 30 degrees. . Such a modification will be described in detail with reference to FIGS. 9 and 10.

  Here, FIG. 9 is a diagram illustrating the incident angle dependency of the transmittance for light (blue light) having a wavelength of 450 nm according to the modification, and FIG. 10 is a diagram illustrating light (wavelength 600 nm according to the modification). It is a figure which shows the incident angle dependence of the transmittance | permeability with respect to (red light). 9 and 10, as in FIGS. 6 and 7, the horizontal axis represents the incident angle (degrees) and the vertical axis represents the transmittance. The incident angle of 0 degree is defined as a direction perpendicular to the main surface of the sample filter x (exposed surface of the glass substrate) as in the case of FIGS.

  As shown in FIG. 9, it was found that the sample filter x satisfactorily transmitted light having a wavelength of 450 nm at an incident angle of 0 degree to an incident angle of 40 degrees. Specifically, the transmittance with respect to light having a wavelength of 450 nm is about 0.90 (90%) from the incident angle of 0 degree to the incident angle of 40 degrees, and the value is substantially maintained. When the incident angle exceeds 40 degrees, the transmittance gradually decreases. When the incident angle is 60 degrees, the transmittance is about 0.80 (80%). When the incident angle exceeds 60 degrees, the transmittance is reduced. It decreases sharply and the transmittance is about 0.45 (45%) at an incident angle of 80 degrees. That is, the incident angle dependence of the transmittance for light having a wavelength of 450 nm in the sample filter x is equivalent to the incident angle dependence of the sample filters a to d shown in FIG.

  On the other hand, as shown in FIG. 10, it was found that the sample filter x satisfactorily blocked light having a wavelength of 600 nm at an incident angle of 0 degree to an incident angle of 30 degrees. In the sample filter a, the transmittance sharply increases when the incident angle exceeds 30 degrees, reaches the transmittance peak at the incident angle of 60 degrees, and decreases when the incident angle exceeds 60 degrees. That is, the incident angle dependence of the transmittance for light having a wavelength of 600 nm in the sample filter x is equivalent to the incident angle dependence of the sample filter a shown in FIG.

  As described above, when the incident angle is 0 degree to 30 degrees, the blue light is transmitted while the red light is shielded, and when the incident angle is 40 degrees or more, the blue light is shielded while the red light is transmitted. Even with this filter, the same effects as those of the above-described embodiment can be obtained. This is because, by comparison, blue light is reflected at a high incident angle (40 ° or more), and even with a small amount of phosphor, wavelength conversion by blue light can be sufficiently performed. In addition, it is considered that white light can be efficiently synthesized using wavelength-converted light because red light can be satisfactorily transmitted at a relatively high incident angle (40 degrees or more).

DESCRIPTION OF SYMBOLS 1 Semiconductor light-emitting device 2 Wiring board 3 LED chip 4 Wavelength conversion member 5 Spacer 6 P electrode 7 N electrode 8 Wiring pattern 9 Wiring pattern 11 Transparent member 11a Phosphor 11b Resin 12 Filter

Claims (9)

A wavelength conversion member that converts the wavelength of at least a part of incident blue light, synthesizes a plurality of visible lights, and emits synthetic white light,
A phosphor that absorbs at least part of the blue light and emits light having a wavelength different from that of the blue light, and a transparent member made of a base material that holds the phosphor;
The average transmittance in the range of incident angles of 0 to 30 degrees of the first visible light constituting the synthetic white light is 20% or less, and from the incident angle of 0 degrees of the second visible light constituting the synthetic white light. A filter having an average transmittance of 80% or more in a range of 30 degrees,
The wavelength conversion member, wherein the filter is located on an emission side of the synthetic white light.   The first visible light is the blue light having a peak wavelength in the range of 430 nm to 470 nm, and the second visible light is red light having a peak wavelength in the range of 550 nm to 700 nm. Item 2. The wavelength conversion member according to Item 1.   2. The filter according to claim 1, wherein the average transmittance of the blue light increases from an incident angle of 0 degree to 50 degrees, and the average transmittance of the red light decreases from an incident angle of 0 degrees to 50 degrees. Or the wavelength conversion member of 2.   4. The filter according to claim 1, wherein the filter has an average transmittance of the blue light of 50% or less and an average transmittance of the red light of 80% or more at an incident angle of 0 to 40 degrees. The wavelength conversion member of any one of Claims 1.   5. The wavelength conversion member according to claim 1, wherein the filter has an average transmittance of the blue light of 20% or less at an incident angle of 0 degree.   The wavelength conversion member according to any one of claims 1 to 5, wherein the filter has an average transmittance of 60% or more for the blue light at an incident angle of 60 degrees.   The first visible light is red light having a peak wavelength in a range of 550 nm to 700 nm, and the second visible light is the blue light having a peak wavelength in a range of 430 nm to 470 nm. Item 2. The wavelength conversion member according to Item 1.   The wavelength conversion member according to claim 1, wherein the filter includes a dielectric multilayer film. The wavelength conversion member according to any one of claims 1 to 8,
A semiconductor light emitting device that emits the blue light toward the wavelength conversion member.

Images