JP2016119280A - Luminaire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in which heat radiation properties of LED lighting needs improving, and a method of efficiently radiating heat is desired by avoiding increase in size of a metal housing and increase in weight.SOLUTION: A luminaire is used which includes a light emitting element, a plastic molding for covering the light emitting element, and a housing combined with the light emitting element and the plastic molding, and in which the plastic molding has a thin metallic wire inside. Furthermore, the luminaire is used in which the plastic molding includes matrix resin and particles of infrared radiation filler, and in which the concentration of the infrared radiation filler is 40 wt.% or less of the plastic molding.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a lighting device. In particular, it is related with the illuminating device using LED.

  In recent years, with the progress of energy saving, LED lighting devices that consume less power, have a longer life, and have higher luminous efficiency than conventional light bulbs and fluorescent lamps have been attracting attention for a long time. Currently, LED lighting devices are replacing traditional lighting at a fairly fast pace. The LED lighting device has a low calorific value and high efficiency as compared with conventional lighting, but heat dissipation is still a big problem due to the increase in size and power of lighting equipment.

  FIG. 9 shows a side view of a conventional LED lighting device (Patent Document 1). In the structure of the conventional LED lighting device, the heat generated in the LED 1 is guided to the metal casing 3 of the LED lighting device via the circuit board 7. Thereafter, the heat is radiated into the room temperature atmosphere from the outer surface of the metal housing 3 by radiation (radiation) of the far infrared rays 4.

  The material of the metal housing 3 is often made of metal, mainly aluminum. Furthermore, the surface of aluminum is generally oxidized and covered with an alumite film. The alumite film is a material having a high emissivity of the far-infrared ray 4 and can radiate (radiate) the far-infrared ray 4 depending on a temperature difference between the surface temperature of the alumite film and room temperature. This dissipates heat. On the other hand, since the transparent light transmitting portion 2 through which light passes is a resin having low thermal conductivity, almost no heat is transmitted and no heat dissipation is performed.

JP 2011-126262 A

  The LED lighting device has recently been increased in brightness. Along with this, the amount of heat generation is also increasing. As a result, heat dissipation is a major issue. In order to dissipate heat, it is effective to increase the surface area of the metal casing 3 described above. However, problems such as an increase in the size of the LED lighting device, an increase in weight, and a deterioration in design will occur. Therefore, the improvement of the efficient heat dissipation of a LED lighting apparatus is a big subject.

  For this reason, the subject of this invention is providing the illuminating device which avoids the enlargement and weight increase of a metal housing | casing, and thermally radiates efficiently.

  In order to achieve the above object, a light-emitting element, a plastic molded article covering the light-emitting element, and a housing combined with the light-emitting element and the plastic molded article, the plastic molded article having a thin metal wire inside Use the device.

In the illuminating device of this invention, the heat | fever of a light source is guide | induced to a transparent shaping | molding part through a thin metal wire. Since the transparent molded part contains an inorganic filler with high heat radiation, it can radiate heat into the atmosphere in the air as far infrared rays. As a result, it is possible to efficiently dissipate heat, and it is possible to reduce the heat of the light source and suppress the temperature rise.
Moreover, since heat radiation by far-infrared radiation can be normally performed from a transparent molded part that does not contribute to heat dissipation, the casing part other than the transparent molded part can be made small. As a result, the lighting device can be reduced in size and weight, and excellent design can be provided.

External view of LED lighting device of embodiment The figure of a part of cross section of the light transmissive part of LED illuminating device (FIG. 1) of embodiment Sectional drawing of the illuminating device (FIG. 1) of embodiment Sectional drawing of the LED lighting apparatus of Examples 1-6 of embodiment and Comparative Examples 1-2 Sectional drawing of the connection part of the metal substrate and light transmissive part of LED lighting apparatus (FIG. 4) of embodiment Top view of LED lighting device (FIG. 5) of Example 1 Top view of LED lighting device (FIG. 5) of Example 2 Top view of the LED lighting device (FIG. 5) of Example 3 Illustration of a cross-sectional example of a conventional LED lighting device

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
An example of the structure of the LED lighting device of Embodiment 1 of the present invention is shown in FIG. FIG. 1 is a perspective view of an LED lighting device according to an embodiment. It consists of a metal housing 3, a plastic molded product 6, a fine metal wire 5, and an LED 1. The metal housing 3 has a smaller surface area than the conventional structure of FIG. Therefore, the heat radiation from this metal housing 3 is reduced.

  On the other hand, a transparent and heat-resistant plastic (hereinafter referred to as a plastic molded product 6) is used as the plastic molded product 6 through which light from the LED lighting device passes. Furthermore, a fine metal wire 5 is taken into the plastic molded product 6. The metal fine wire 5 is inserted into the plastic molded product 6 by insert molding.

  In this structure, the heat generated along with the light emission of the LED 1 is thermally diffused throughout the metal housing 3 having good thermal conductivity such as aluminum. Further, the heat spreads from the metal housing 3 through the fine metal wire 5 to the entire plastic molded product 6. Furthermore, the plastic molded product 6 rises in temperature, converts heat into far infrared rays 4 and radiates it into the air, whereby the heat of the LED 1 can be radiated and lowered.

  That is, compared with FIG. 9 of a general LED lighting device, FIG. 1 of the LED lighting device of the present invention is an LED lighting device having an epoch-making structure capable of radiating heat from a portion through which light is transmitted.

  FIG. 2 shows a partially enlarged view of the plastic molded product 6 of FIG. 1 according to Embodiment 1 of the present invention. The thin metal wire 5 is inserted into the plastic molded product 6 by insert molding. The metal thin wire 5 is not limited. However, it is made of a metal having good thermal conductivity, for example, aluminum, copper or SUS, and heat from the LED 1 can be diffused throughout the plastic molded product 6. The volume and arrangement of the fine metal wires 5 will be described separately below.

<Filler>
In order to increase the radiation efficiency of the far-infrared rays 4, it is preferable that the plastic molded product 6 contains particles of infrared radiation filler in the matrix resin. The matrix resin itself preferably has a radiation efficiency of far infrared rays 4 of 0.5 to 0.8, which is higher than a general metal emissivity of 0.05 to 0.2. Furthermore, the emissivity of the far-infrared rays 4 is further increased by further mixing filler particles having a high emissivity into the resin. As a result, the heat dissipation effect is further increased.

  However, when the content ratio of the infrared radiation filler is too high, the visible light transmittance of the plastic molded product 6 is lowered. In general, when the visible light transmittance is lower than 40%, it feels dark because the amount of light is small. In addition, since the LED lighting device of the present invention is formed with a thin metal wire that blocks light in the plastic molded product 6, the amount of transmitted light is further reduced. Therefore, the visible light transmittance of the plastic molded product 6 of the present invention is preferably 40% or more.

  Moreover, in order to maintain the visible light transmittance of 40% or more, it is preferable that the content ratio of the appropriate infrared radiation filler particles is up to 40% by weight (from the results of the following examples).

  Infrared radiation filler is selected from enstetite, uremite, deobside, forsterite, zircon, cordierite, hydrotalcite, steatite, mullite, petalite, spojumen, wollastonite, anorthite, part-time radiation At least one of the ceramics is desirable.

In particular, cordierite (2MgO · 2Al ₂ O ₃ · 5SiO ₂ ), which is an artificial mineral, has a large emissivity of 0.90 to 0.97 (wavelength 6 μm), and thus is an excellent far-infrared ray as a thermal radiation filler Exhibits radioactivity.

  Further, the size of the particle of the external radiation filler is not particularly limited, but a submicron size is desirable in order not to lower the light transmittance.

  The matrix resin of the plastic molded product 6 is made of a group consisting of polyethylene, polypropylene, polyester, polybutylene terephthalate, polycarbonate, polymethylpentene, polyolefin, polyarylate, and polyether ketone. It is desirable to be at least one resin selected from the above.

  The heat of the LED 1 is transmitted to the plastic molded product 6 by the thin metal wire 5 that is insert-molded into the transparent heat-resistant plastic molded product 6. Since the plastic molded product 6 generates heat up to about 100 ° C., it is essential that the plastic molded product 6 be a plastic material that does not deteriorate even when exposed to a high temperature for a long time.

  Further, the material of the heat-resistant transparent plastic molded product 6 is not particularly limited, but it is necessary to include a far-infrared radiation filler fine powder in an appropriate interior and to be able to insert-mold the fine metal wire 5. A thermoplastic plastic that can provide appropriate fluidity when heated and melted is desirable.

  Next, FIG. 3 shows a cross-sectional view of the LED lighting device of the present invention. The heat-resistant and transparent plastic molded product 6 has an upwardly convex curved shape, and has a very large area because it protrudes outside the width of the metal housing 3. Can be radiated efficiently.

(Embodiment 2)
Next, in FIG. 4, sectional drawing of the LED lighting apparatus of Embodiment 2 is shown. The difference from the first embodiment is that the shape of the plastic molded product 6 through which the light of the LED 1 passes is a flat surface. The mechanism in which the light from the LED 1 is transmitted through the fine metal wire 5 to the plastic molded product 6 and is dissipated by the radiation of the far infrared rays 4 is the same as in the first embodiment.

  In Embodiment 1 of FIG. 3, the plastic molded product 6 of the light transmitting part is curved and has a shape protruding from the metal casing 3. The upper surface of 6 is flat. For this reason, the distance of the metal fine wire 5 and LED1 can be shortened. Therefore, the attenuation of heat transmitted from the LED 1 that is the heat generating portion can be reduced. As a result, the heat of the LED 1 can be efficiently guided to the plastic molded product 6, and the heat dissipation efficiency can be increased. In particular, the upper surface of the LED 1 is preferably a flat surface.

  FIG. 5 shows an enlarged view of a connecting portion between the metal casing 3 and the plastic molded product 6 in FIG. The heat of the metal housing 3 is transmitted from the metal housing 3 to the thin metal wire 5. The enlarged view of the connection part between the metal housing | casing 3 and the plastic molded product 6 is shown. The enlarged view of the connection part between the metal housing | casing 3 and the plastic molded product 6 is shown. The connection between the metal housing 3 and the thin metal wire 5 needs to be a connection that does not attenuate the heat conduction. For example, solder bonding, metal brazing, and fitting are preferable. By adopting the connection structure, heat spreads to the plastic molded product 6 through the fine metal wires 5 and radiates heat to the outside through the far infrared rays 4.

(Embodiment 3)
FIG. 6 shows a top view of the plastic molded product 6. As a lighting device, it is necessary to transmit necessary light. Therefore, the metal fine wire 5 in FIG. 6 uses a metal mesh.

  Since the metal mesh is a combination of warp and weft, it has strength and excellent heat conduction. The fine metal wire 5 having a mesh structure is insert-molded inside a heat-resistant transparent plastic molded product 6. With this structure, deterioration due to oxidation of the metal part can be suppressed, and the touch can be improved.

  A thin metal wire 5 is insert-molded in a plastic molded product 6. The ratio of the mesh-type fine metal wires 5 in the entire plastic molded product 6 is preferably 5 to 35% or less of the entire surface of the plastic molded product 6.

  When it is larger than 35%, the light passing portion is reduced, and the effect of brightly illuminating as an original lighting device is lowered.

  If it is 5% or less, the thermal conductivity is lowered, so the heat dissipation effect is reduced, and the LED temperature is increased. This ratio is irrelevant to the arrangement of the thin metal wires 5.

  Next, another embodiment of the thin metal wire 5 is shown in FIGS. FIG. 7 is a diagram corresponding to FIG. 6. FIG. 7 shows a product obtained by insert-molding a Hankham (large) structure as a thin metal wire 5 on a transparent heat-resistant plastic molded product 6. There is a pentagonal opening.

  FIG. 8 is a fine type of the Hancam structure shown in FIG. 7 and is a honeycomb (small). The honeycomb structure has high strength and can be formed by punching. It is suitable for making resin molded products with flat structure without unevenness. The material may be an alloy such as SUS, but if anodized aluminum is used, the far-infrared emissivity is higher than that of aluminum, so that the thermal radiation effect can be increased (normal aluminum: emissivity). 0.2, anodized: emissivity 0.8).

  Further, in the case of the Hancam structure (large) (FIG. 7), the position of the LED 1 located inside the plastic molded product 6 is just below the intersection of the thin metal wires 5, especially the thin wires. Passage is inhibited. For this reason, when LED1 is seen from the front (plan view), it is preferable to be located under the opening (vertically below) of the opening portion of the Hancam structure, particularly near the lower portion of the central portion of the opening portion. The position of the LED 1 is preferably arranged inside the opening without overlapping the metal thin wire 5 when the LED 1 is viewed from the front. The hexagonal shape of FIGS. 7 and 8 is more preferable than the rectangular shape of the opening of FIG.

  This is the same in FIGS. 6 and 8 regardless of the arrangement of the thin lines. Moreover, as shown in FIGS. 7 and 8, there are a plurality of LEDs 1 and their arrangement is arranged in a circle. The positions of the respective LEDs 1 are preferably the same with respect to the respective openings. The light comes out evenly.

  In the third embodiment, the heat transmitted to the metal casing 3 made of aluminum die-casting on the side surface through the metal member is transmitted through the insert-molded fine metal wire 5 into the plastic molded product 6 of the light transmitting portion. Thus, it diffuses throughout the plastic molded product 6.

  In general, the transparent plastic molded product 6 through which light is transmitted does not become very hot. However, in this embodiment, since the heat is efficiently transmitted to the plastic molded product 6, the temperature rises to 60 ° C. or higher. To do. And by radiating far-infrared rays 4 in the air from there, heat dissipation occurs, and the temperature of the LED 1 can be lowered from them.

<Examination on plastic molded product 6>
Next, the plastic molded product 6 according to the present embodiment was examined. An example is given and it demonstrates concretely. However, the present embodiment is not limited to those shown in the following examples, and can be implemented with appropriate modifications within a range not changing the gist thereof.

  Table 1 shows the configurations of the LED lighting devices used in the examples and comparative examples.

※ 1: cordierite _{2MgO · 2Al 2 O 3 · 5SiO} 2 ( Mars glaze manufactured by SS100: average particle size of 18μm)
※ 2: forsterite 2MgO · SiO ₂ Mars glaze, Inc. FF200 (average particle diameter of 3μm)
* 3: Steatite MgO / SiO ₂ SB12S (average particle size: 8 μm) manufactured by Yakusu glaze
* 4: Surface coverage of the molded article of the metal thin wire or metal thin film * 5: Visible light transmittance of the resin part (filler included) of the molded article * 6: The outer central portion of the upper part of the molded article in FIG. Temperature (Example 1)
High molecular weight polypropylene (heat resistant temperature 140 ° C.) was used as the resin of the transparent heat resistant plastic molded product 6. As the thermal radiation filler, 10 wt% of cordierite (2MgO · 2Al ₂ O ₃ · 5SiO ₂ ) particles having a size of 200 nm was used.

  The visible light transmittance of the resin was 80%. Further, a structure in which 8 mesh 5a (opening ratio: 71%, wire diameter: 1 mm) made of SUS304 stainless steel was taken into the inside by insert molding was formed on the resin containing the filler, thereby forming a molded product. Therefore, the surface coverage of the metal mesh in the transparent heat-resistant plastic molded product was 30%. Using this transparent heat-resistant plastic molded product 6, a molded product shown in FIG. 4 was created to complete LED lighting.

  The diameter of the molded product in FIG. 4 was 800 mm and the thickness was 3 mm. The LED was a surface-mount type high-brightness chip LED with a 7.2 W LED, and 12 LEDs were mounted on a printed circuit board. Moreover, the shape of the LED lighting fixture was a shape shown in FIG.

(Examples 2 to 6)
A transparent heat-resistant plastic molded article having the form shown in FIG. 4 similar to that in Example 1 was prepared using the base resin type, metal shape, and filler shown in Table 1, and evaluation was performed under the same conditions as in Example 1. .

  As the thermal radiation filler, forsterite and steatite were used as shown in Table 1 in addition to the cordierite of Example 1.

  As the polycarbonate, a grade having a heat resistant temperature of 130 ° C. was used. The polymethylpentene used was a grade having a heat resistant temperature of 160 ° C. As the metal for heat conduction for base resin insert molding, mesh (FIG. 6), honeycomb (large) (FIG. 7), and honeycomb (small) (FIG. 8) were used.

  In Example 6, the same mesh as that in Example 1 was used. In Example 2, a honeycomb (large) was used. As shown in FIG. 7, this is a metal foil having a thickness of 0.3 mm, in which hexagonal honeycomb-shaped holes are formed, the distance between adjacent holes is 2 mm, and the diagonal length of the honeycomb is It was 8 mm. The surface coverage of the honeycomb (large) was 35%.

  In Examples 3, 4, 5 and Comparative Example 2, a honeycomb (small) was used. This was a metal foil having a thickness of 0.2 mm, a distance between adjacent holes of 0.5 mm, and the diagonal length of the honeycomb. The thickness was 4 mm. The surface coverage of the honeycomb (small) was 15%.

(Comparative Example 1)
The same high molecular weight polypropylene (heat resistant temperature 140 ° C.) as in Example 1 was used as the base resin, but there was no fine metal wire 5 for conducting heat, and no inorganic filler for increasing the infrared emissivity. Using this, a molded product of a transparent and heat-resistant plastic molded product 6 having the same form as in Example 1 was prepared and evaluated under the same conditions as in Example 1.

(Comparative Example 2)
As the polyvinyl chloride of the comparative example, a grade having a heat resistant temperature of 40 ° C. was used. The thin metal wire 5 to be inserted uses the above-mentioned honeycomb (small), and uses a cordierite-containing material as the heat-radiating filler, and the transparent heat-resistant plastic molded product 6 having the same form as in Example 1 is used. Molded products were prepared and evaluated under the same conditions as in Example 1.

(Evaluation)
Evaluation sets this LED lighting fixture in the thermostat kept at 20 degreeC, it energizes in a windless state and light-emits LED. The LED element temperature and the surface temperature of the transparent heat-resistant plastic molded product were measured 1 hour after the light emission and when the temperature was stabilized. In addition, the surface temperature of the heat-resistant plastic molded product was measured by measuring the temperature at the upper center of the circular central portion (FIG. 4).

The temperature rise suppression temperature (ΔT) will be described. The LED lighting device having the heat dissipation structure of the present embodiment and the LED lighting device having the normal structure (Comparative Example 1) were used to measure the temperature of each LED, and the temperature difference was expressed by the following formula 1.
Temperature difference ΔT = [LED temperature of Comparative Example 1−LED temperature of other examples] (Equation 1)
The temperature rise suppression rate was set to Formula 2.
Temperature rise inhibition rate (%) = ([LED temperature of Comparative Example 1−LED temperature of other examples] / LED temperature of Comparative Example 1) × 100 (Equation 2)
It was. When the temperature rise inhibition rate (%) is 0 to less than 3%, x is less than 3 to 10%, Δ is 11 to less than 20%, and ◯ is 20% or more.

<Regarding temperature rise suppression>
As shown in the results of Example 1, the temperature of the LED is 122 ° C., which has a temperature increase suppression effect of 18 ° C. and a temperature increase suppression rate of 12.8% compared to Comparative Example 1 having a small heat dissipation effect. It has been found. It has been discovered that this temperature suppression effect is very effective as a countermeasure against a decrease in light emission efficiency of the LED as the temperature rises. This is presumed to be due to the effective heat radiation effect that infrared rays could be radiated efficiently in the air from the transparent plastic molded part of the light transmitting part that had not been used so effectively until now. Is done.

  From the results of Example 2, it was found that a structure having a hole in the honeycomb (large) in the metal portion that conducts heat has an excellent effect.

  From the results of Example 3, it was confirmed that polymethylpentene was used as the base resin, and the metal part that conducts heat had a structure with a hole in the honeycomb (small). There was found.

  Similarly, it was found that the combination of Examples 4 to 6 also has an excellent temperature rise suppressing effect.

  In Comparative Example 1, it can be seen that the temperature of the LED 1 is the highest and the heat dissipation effect from the plastic molded product 6 is small. Further, in Comparative Example 2, the plastic molded product 6 was colored brown and a hole was partially opened in 18 hours after the LED 1 was turned on. Furthermore, although it is guessed that there is little heat radiation, the fall of the temperature of LED1 was small.

<Metallic thin wire>
When the mesh (FIG. 6) was used, the surface coverage of the honeycomb formed article of the fine metal wires 5 was 30%, the honeycomb (large, FIG. 7) was 35%, and the honeycomb (small, FIG. 8) was 15%. Since the heat of the LED 1 is diffused through the thin metal wire 5 and throughout the molded product, the coverage of the molded product surface of the fine metal wire 5 is a very important factor in terms of heat dissipation. The higher the coverage, the more the heat is transferred to the entire molded product, and the surface temperature of the molded product tends to increase. In Example 2, the surface coverage is 35%, the honeycomb is large, and the surface temperature of the molded product is 81 ° C., which is the highest. In order to increase the surface temperature of the molded product, it is effective to increase the coverage, but if it is too high, the LED light passing through the molded product will be reduced. 15-35% of 1-5 is suitable (Table 1).

<Filler>
Next, in order to suppress the temperature rise of the LED 1, it is necessary to spread the heat of the LED 1 over the entire plastic molded product 6 and radiate it into the air as far infrared rays 4 therefrom. For that purpose, the emissivity ε for converting heat into far-infrared rays 4 is important. In order to increase the conversion efficiency to the far infrared ray 4, it is effective to include a filler having a high emissivity ε of the far infrared ray 4 in the plastic molded product 6.

  In Example 1, the far-infrared emissivity ε was 0.80 by kneading 10% of cordierite fine particles having a high emissivity into the resin. On the contrary, in Example 3, since the filler was not mixed, the emissivity of the resin alone was 0.65. That is, it can be seen that the emissivity ε greatly depends on the amount of far-infrared radiation filler mixed therein.

  However, as the filler ratio is increased, the light transmittance of the resin molded product becomes lower. The light transmittance as LED illumination is an important item, and it is desirable that the visible light transmittance is 40% or more as a lighting device.

  In order to maintain the transmittance of 40% or more, the filler ratio to be kneaded is preferably up to 40% by weight (Example 5). Further, the far infrared emissivity ε is preferably larger than 0.5.

  When the far-infrared emissivity ε is 0.5 or less, it is necessary to increase the filler concentration. However, the amount is limited due to the above-described transmittance problem. At least, the far-infrared emissivity ε needs to be larger than 0.5.

<Resin>
Next, in terms of plastic materials, when an LED emits light, it generates heat up to about 140 ° C. Therefore, as shown in Comparative Example 2, when using a plastic having low heat resistance such as polyvinyl chloride, the LED emits light. It has been found that the visible light transmittance is lowered due to oxidative degradation due to heat and discoloration. Therefore, the heat resistance of the plastic resin needs to be at least 80 ° C. or higher, desirably 100 ° C. or higher.

<Effect>
In normal lighting, the temperature of the LED 1 is 140 ° C. as shown in Comparative Example 1, but the structure of the present embodiment can be adopted. In the structure of Example 1, the temperature can be lowered by 18 ° C. It has been found that the LED temperature decrease (ΔT) increases as the surface temperature of the molded article increases and the far-infrared radiation ε increases. As in Example 2, when the surface coverage of the molded article is high and the far infrared emissivity ε is high, the LED temperature decreases by 33 ° C., and the temperature rise suppression rate compared to Comparative Example 1 of the reference is 23.6%, which was found to be very high.

  In the present embodiment, heat from the LED 1 is thermally conducted by the thin metal wire 5 formed inside the transparent plastic molded product 6 to raise the temperature of the plastic molded product 6. Furthermore, it has been found that by mixing a filler having a high far-infrared emissivity into the plastic molded product 6, it is possible to efficiently radiate far-infrared rays into the air and suppress the temperature rise of the LED 1. . By forming the structure of this LED illumination, the energy of the LED 1 can be efficiently reduced and the temperature rise can be suppressed, and the LED illumination apparatus can be reduced in size and weight.

(Note)
Although the above was described regarding the illuminating device using the LED light source, the illuminating device having a light source other than the LED light source can be used similarly. Embodiments can be combined.

  It can be widely used as an LED lighting device. It can be widely used in lighting equipment such as home lighting, automobile lighting, and building lighting. Not only LEDs but also other heat generating light sources such as fluorescent lamps can be used similarly.

1 LED
2 Light transmission part 3 Metal housing 4 Far infrared ray 5 Metal fine wire 6 Plastic molded product 7 Circuit board

Claims (8)

A light emitting element;
A plastic molded article covering the light emitting element;
A lighting device including a housing combined with the light emitting element and the plastic molded product, wherein the plastic molded product has a metal thin wire inside. The plastic molded article includes matrix resin and infrared radiation filler particles,
The lighting device according to claim 1, wherein a concentration of the infrared radiation filler is 40% by weight or less of the plastic molded product. 3. The lighting device according to claim 1, wherein the plastic molded article has a visible light transmittance of 40% or more, a heat resistant temperature of 60 ° C. or more, and a far infrared emissivity ε at 60 ° C. of 0.5 or more. The lighting device according to any one of claims 1 to 3, wherein the thin metal wire has a mesh structure or a honeycomb structure. The lighting device according to any one of claims 1 to 4, wherein the thin metal wire and the light emitting element are not disposed so as not to overlap when the light emitting element is viewed from the front. The surface covering rate of the said metal fine wire is 10 to 35% of the whole surface of the said plastic molded product, The illuminating device of any one of Claims 1-5 characterized by the above-mentioned. The lighting device according to any one of claims 1 to 6, wherein the thin metal wire has an opening, and the light emitting element is disposed in the opening when the light emitting element is viewed from the front. The lighting device according to claim 1, wherein the light emitting element is an LED.

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