JP2017199737A - Light emitting diode-mounted module, and light reflective member for light emitting diode-mounted module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting diode-mounted module showing good front-face brightness.SOLUTION: A light emitting diode-mounted module 10 comprises: a light-emitting diode-mounting substrate 11; a light emitting diode 20 disposed on at least one face side of the light-emitting diode-mounting substrate; and a light reflective member 15 disposed on the same side as the face of the light-emitting diode-mounting substrate where the light emitting diode is disposed. The light reflective member includes: a porous first resin sheet having a first face and a second face opposite to the first face; and a dense second resin sheet disposed on the first face side of the porous resin sheet. The light-emitting diode-mounting substrate is disposed on the second face side of the first resin sheet of the light reflective member.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to a light emitting diode mounting module and a light reflecting member for a light emitting diode mounting module. The present invention also relates to a display device and a lighting device including a light emitting diode mounting module.

  In recent years, an LED mounting module in which a light emitting diode (which may be described as “LED” in the following) is mounted as a light source of a display device or a lighting device has been spreading. In the LED mounting module, the LED is arranged on at least one surface side of the LED mounting substrate, and light emitted from the LED passes through the light guide member as necessary and is emitted from the LED mounting module. To do.

  In the LED mounting module, in order to efficiently use the light emitted from the LED, a light reflecting member may be arranged around the LED and the light guide member. As the light reflecting member, for example, a member using a porous resin sheet having a plurality of voids therein is known.

  Patent Document 1 discloses a biaxially stretched laminated polyester film having a two-layer structure in which a polyester layer (A) and a polyester layer (B) containing cavities are laminated by a coextrusion method, and further has predetermined requirements. A white laminated polyester film for a reflector that satisfies the requirements is disclosed.

  Patent Document 2 discloses a wiring board installed at the bottom of a box whose front surface is open, a plurality of light emitting elements installed on the wiring board, and light reflections spread so as to fill a space between the light emitting elements. A light box comprising a light-transmitting light diffusing surface plate installed at the front opening of the plate and the box body, and there is a gap between the light emitting portion of the light emitting element and the light reflecting plate, A light diffusing reflection plate having a plurality of through-holes is installed between the light emitting portion of the light emitting element and the light diffusing surface plate, and the diffuse reflectance of visible light on both surfaces of the light diffusing reflection plate is 90% or more A light box is disclosed.

JP 2008-309975 A Japanese Patent No. 4316556

  Since the porous resin sheet has many voids inside, it is difficult to improve the smoothness of the surface, and the light reflecting member using the porous resin sheet has a problem that the glossiness is lowered even if the reflectance is high. May occur. An LED mounting module including a light reflecting member having a low glossiness may cause a problem that luminance in the normal direction of the LED mounting module (hereinafter sometimes referred to as “front luminance”) decreases.

  An object of this indication is to provide the LED mounting module which shows favorable front luminance. Moreover, it aims at providing the light reflection member for LED mounting modules which can make front brightness of an LED mounting module favorable.

  One of the light emitting diode mounting modules according to the present disclosure includes: a light emitting diode mounting module; a light emitting diode mounted on at least one surface side of the light emitting diode mounting substrate; and the light emitting diode. A light reflecting member disposed on the same surface side of the mounting substrate as the surface on which the light emitting diode is disposed, the light reflecting member being a second surface opposite to the first surface and the first surface. A porous first resin sheet, and a dense second resin sheet disposed on the first surface side of the porous resin sheet, wherein the light-emitting diode mounting substrate comprises the light reflecting The member is arranged on the second surface side of the first resin sheet.

  Another one of the light-emitting diode mounting modules according to the present disclosure includes: a light-emitting diode mounting module; a light-emitting diode disposed on at least one surface side of the light-emitting diode mounting substrate; A light guide member, which is disposed opposite to the light emitting diode, and a light reflecting member disposed on a different side of the light guide member from the surface facing the light emitting diode. The light reflecting member is disposed on the first surface side of the first resin sheet, the porous first resin sheet having a first surface and a second surface opposite to the first surface, A dense second resin sheet, and the light guide member is disposed on the second surface side of the first resin sheet of the light reflecting member.

  One of the light reflecting materials for a light emitting diode mounting module according to the present disclosure includes a porous first resin sheet having a first surface and a second surface opposite to the first surface, and a first surface of the first resin sheet. And a dense second resin sheet disposed on the one surface side.

  According to the present disclosure, an LED mounting module that exhibits good front luminance can be obtained. The light reflection member for LED mounting modules which can make front brightness of an LED mounting module favorable is obtained.

It is a top view showing typically one embodiment of an LED mounting module of this indication. It is drawing which shows typically the cross section of the AA part of FIG. 1, and is sectional drawing which shows typically one Embodiment of the LED mounting module of this indication. It is sectional drawing which shows typically one Embodiment of the light reflection member used for the LED mounting module of this indication. It is sectional drawing which shows typically another one of embodiment of the light reflection member used for the LED mounting module of this indication. It is sectional drawing which shows typically another one of embodiment of the light reflection member used for the LED mounting module of this indication. It is sectional drawing which shows typically another one of embodiment of the light reflection member used for the LED mounting module of this indication. It is sectional drawing which shows typically another one of embodiment of the LED mounting module of this indication. It is sectional drawing which shows typically another one of embodiment of the LED mounting module of this indication. It is a perspective view which shows typically the display apparatus provided with the board | substrate for LED mounting of this indication.

  Below, embodiment of the LED mounting module of this indication and the light reflection member for LED mounting modules is described. However, the present disclosure is not limited to the following embodiment, and can be implemented with appropriate modifications within the scope of the object of the present disclosure. Further, “sheet”, “film”, and “board” are not distinguished, and “sheet” includes “film” and “board”.

  1 and 2 show one embodiment of the LED mounting module of the present disclosure. The LED mounting module 1 includes an LED mounting substrate 10, an LED 20 disposed on one surface side of the LED mounting substrate 10, and light disposed on the same surface side as the surface on which the LED 20 of the LED mounting substrate 10 is disposed. A reflection member 15 is provided. In the present embodiment, the light reflecting member 15 has a through hole 152 and covers at least a part of the surface of the LED mounting substrate excluding the region where the LED 20 of the LED mounting substrate 10 is disposed. The LED 20 is disposed in the through hole 152 of the light reflecting member 15. In the present embodiment, the insulating protection part 14 is disposed between the LED mounting substrate 10 and the light reflecting member 15. The insulating protection unit 14 can be arranged to suppress insulation failure due to the migration phenomenon, but is not essential. The insulating protection part 14 can be formed of, for example, a thermosetting resin.

  As for the light reflection member 15 arrange | positioned at the LED mounting module 1 of the above-mentioned embodiment, at least one surface shows favorable glossiness. Reflection of light has regular reflection contribution and diffuse reflection contribution. A reflective surface with a high glossiness has a small contribution of diffuse reflection, and light reflected by the reflective surface with a high glossiness is difficult to spread. On the other hand, the light emitted from the LED has strong directivity, and has directivity toward the normal direction (front direction) of the LED mounting substrate 10. It can be said that the light from the LED reflected by the reflective surface having a high glossiness can maintain the initial directivity more easily than the light from the LED reflected by the reflective surface having a low glossiness. Therefore, the LED mounting module 1 of the above-described embodiment shows a good front luminance.

  As shown in FIG. 2, the LED mounting substrate 10 has a wiring portion 12 formed on one surface side of a support 11 via an adhesive layer (not shown). In addition, the wiring part 12 is electrically connected to the LED 20 by, for example, the conductive joint part 13.

  For example, glass or resin can be used as the support 11 of the LED mounting substrate 10. Since it becomes difficult to break even if the LED mounting module is bent, a flexible glass sheet or resin sheet is preferable. Specific examples of the resin used in the resin sheet include polyimide, polyamideimide, polynylon, polycarbonate, polyethersulfone, acrylic, polyester such as polyethylene naphthalate and polyethylene terephthalate.

  Although the heat shrink start temperature of the material constituting the support 11 is not particularly limited, it is preferably over 90 ° C. This is because, in general, the temperature of the substrate around the LED may rise to about 90 ° C. due to heat generated from the LED. The thermal shrinkage start temperature is determined by the following procedure. First, a sample is taken from the support 11, and the sample is put in a thermomechanical analysis (TMA) apparatus, heated to 120 ° C. at a temperature rising rate of 2 ° C./min with a load of 1 g, and the amount of shrinkage at that time ( % Display). Next, using a graph that records the relationship between temperature and shrinkage, the temperature that deviates from the 0% baseline due to shrinkage is read, and that temperature is taken as the thermal shrinkage start temperature.

The volume resistivity of the material constituting the support 11 is not particularly limited, but is preferably 10 ¹⁴ Ω · cm or more, and more preferably 10 ¹⁸ Ω · cm or more. This is because, in general, a certain insulating property may be required for the LED mounting substrate.

  Although the thickness of the support body 11 is not specifically limited, For example, they are 10 micrometers or more and 100 micrometers or less.

  The wiring portion 12 of the LED mounting substrate 10 has a conductive wiring pattern, and a conductive material such as metal or conductive plastic can be used for the wiring.

  The LED 20 can be a light emitting semiconductor element that utilizes light emission at a PN junction where a P-type semiconductor and an N-type semiconductor are joined. An organic electroluminescence element is also included in the LED. In the present embodiment, as shown in FIG. 2, the LED 20 is electrically bonded to the wiring portion 12 of the LED mounting substrate 10 by, for example, a conductive bonding portion 13. For the conductive joint 13, for example, a bonding agent or solder having a conductive material such as metal or conductive plastic can be used.

  The light reflecting member 15 has a reflection performance for at least a certain range of light within the visible light wavelength region. In one embodiment of the light reflecting member 15, as shown in FIG. 3, a porous first resin sheet 150 and a dense second resin sheet disposed on one surface side of the first resin sheet 150. 151. The first resin sheet 150 and the second resin sheet 151 are joined with an adhesive (not shown). The first resin sheet 150 has a first surface and a second surface opposite to the first surface, and the surface of the first resin sheet 150 on which the second resin sheet 151 is disposed is the first surface. One side. The second surface side of the first resin sheet 150, that is, the surface side opposite to the surface on which the second resin sheet 151 of the first resin sheet 150 is disposed is the surface on which the light emitting diode mounting substrate 1 is disposed. On the side.

  Since the porous first resin sheet 150 having a plurality of voids therein has many voids therein, it is difficult to improve the smoothness of the surface, and the light reflecting member 15 using the porous first resin sheet 150 has a reflectance. Even if it is high, the glossiness tends to decrease. Therefore, since the light reflecting member 15 of FIG. 3 includes the dense second resin sheet 151 on one surface side of the porous first resin sheet 150, the light reflecting member 15 exhibits good glossiness.

  In addition, since the porous first resin sheet 150 has many voids therein, the porous first resin sheet 150 itself tends to be brittle, and there is a concern about durability and workability. Therefore, since the light reflecting member 15 of FIG. 3 includes the second resin sheet 151 that supports the first resin sheet 150, the light reflecting member 15 exhibits good durability and workability. Since the light reflecting member 15 of FIG. 3 has good workability such as bending, cutting, or punching, for example, when a through hole is formed in the light reflecting member 15, burrs, breaks, breaks, etc. of the cut portion are caused. It becomes difficult to generate | occur | produce and it can suppress that the light reflection member 15 arrange | positioned around LED20 disturbs the light from LED20. Therefore, the LED mounting module 1 of the present embodiment shows good quality.

  The first resin sheet 150 is a porous resin sheet having a plurality of voids therein. Since the porous resin sheet has a large internal specific surface area and the shape of the voids is not uniform, it exhibits light reflectivity.

  The first resin sheet 150 is not particularly limited, but is preferably a polyolefin sheet such as polyethylene or polypropylene. This is because the polyolefin sheet is hard to adhere to dirt and hardly changes in shape due to hydrolysis over time, so that the light reflection performance is hardly lowered. Since the first resin sheet 150 has relatively high heat resistance, a polypropylene sheet is more preferable. Although content of the resin in the 1st resin sheet 150 is not specifically limited, For example, it is 50 to 100 mass%. In addition, resin other than polyolefin may be mixed with the polyolefin sheet, and polyolefin should just contain 50 mass% among resin which comprises the 1st resin sheet 150. FIG.

  The first resin sheet 150 can contain a plurality of particles in order to form voids during production or to increase sheet strength. Examples of the particle material include calcium carbonate, talc, silicon oxide, and titanium oxide. The size of the particles is, for example, 0.1 μm or more and 1.5 μm or less. Although content of the micro particle | grains in the 1st resin sheet 150 is not specifically limited, For example, it is 0.1 to 50 mass%.

  Although the thickness of the 1st resin sheet 150 is not specifically limited, For example, they are 20 micrometers or more and 300 micrometers or less.

  Although the magnitude | size of the space | gap which exists in the inside of the 1st resin sheet 150 is not specifically limited, For example, they are 1 micrometer or more and 50 micrometers or less. The tear strength of the porous resin sheet 150 by the Elmendorf tear method varies depending on the thickness, but is, for example, less than 20 mN and sometimes less than 10 mN. In this embodiment, the tear strength by the Elmendorf tear method can be measured in accordance with JIS K7128-2: 1998 (Plastics? Tear strength test method for films and sheets? Part 2: Elmendorf tear method). it can. When the thickness of the sample is thin, the sample value can be determined by measuring a plurality of samples and dividing the obtained measurement value by the number of the stacked samples.

Although the porosity of the 1st resin sheet 150 is not specifically limited, For example, it is 20% or more and 80% or less. Since light reflectivity is good and it does not become excessively brittle, it is more preferably 30% or more and 60% or less. The porosity is an amount per unit volume of the void and can be calculated according to the following formula (1).
Porosity (%) = {(ρ _o −ρ) / ρ _o } × 100 Formula (1)
In the formula (1), ρ is the density of the first resin sheet 150 and can be measured based on JIS P8118. ρ _o is the true density of the first resin sheet 150. The true density can be determined by analyzing the types of main material components constituting the first resin sheet 150 and their constituent ratios and using general values of the types of material components. For example, the density of polypropylene is 0.9 g / cm ³ and the density of calcium carbonate is 2.7 g / cm ³ . In addition, when the 1st resin sheet 150 is what was extended | stretched, unless the material before extending | stretching contains a lot of air, a true density is substantially equal to the density of the material before extending | stretching. Therefore, the true density may be obtained from a material before stretching, and can be obtained by a dry density measuring method by a constant volume expansion method. As a measuring device, for example, a dry automatic densimeter Accupic manufactured by Shimadzu Corporation is available. 1330.

  For example, the first resin sheet 150 has a glossiness of less than 70 at an incident angle of 60 degrees and may be 50 or less. In addition, although a minimum is not specifically limited, For example, it is 0 or more. In this embodiment, the glossiness is JIS Z8741: 1997 “Specular Glossiness—Measurement” with a gloss of 100 as a reflectance of 10% measured on a glass surface with a refractive index of 1.567 at an incident angle of 60 °. It can be measured on the basis of “method”. Specifically, it can be measured by a gloss meter (High gloss gloss checker IG-410 manufactured by Horiba Seisakusho).

  For example, the first resin sheet 150 has a light reflectance of 80% or more, may be 90% or more, and may be 95% or more. The light reflectivity is a characteristic in which the contribution by regular reflection and the contribution by diffuse reflection are comprehensively affected. In this embodiment, the light reflectance is obtained by attaching an integrating sphere attachment device (for example, integrating sphere unit ISN-723) to a spectrophotometer (for example, spectrophotometer V-670DS manufactured by JASCO Corporation), and using barium sulfate. It can be measured as a standard plate. In addition, since the light reflectance is a relative value with respect to barium sulfate, it may exceed 100%. Although an upper limit is not specifically limited, For example, it is 110%.

  Examples of the method for producing the first resin sheet 150 include a method of molding and stretching a composition having a resin and a large number of particles. A porous resin sheet may be produced using a plurality of compositions, and in this case, the plurality of compositions may be the same or different.

  A specific example of a method for producing the first resin sheet 150 is to extrude a first composition having a particle content higher than a second composition to be described later, and then uniaxially stretch to produce a first sheet. A second sheet is produced by extruding a second composition having a particle content smaller than that of the first composition on one side or both sides of the first sheet. Then, the laminate is stretched in a direction different from the stretching direction of the first sheet. By such a method, a porous resin sheet having good light reflectivity can be obtained. Or as another specific example, the method of extending | stretching after joining the 1st sheet | seat and 2nd sheet | seat produced separately with an adhesive agent etc. is mentioned.

  The second resin sheet 151 is a dense resin sheet with a dense interior. Since the dense resin sheet generally has a flat surface compared to the porous resin sheet, the glossiness becomes high. Specific examples of the resin used in the resin sheet include polyimide, polyamideimide, polynylon, polycarbonate, polyethersulfone, acrylic, polyester such as polyethylene naphthalate and polyethylene terephthalate, and polyolefin such as polyethylene and polypropylene. Polyester sheets such as polyethylene naphthalate sheet and polyethylene terephthalate sheet are relatively high in heat resistance and excellent in mechanical properties such as tensile strength and elongation at break. It is suitable as the resin sheet 151. In addition, resin other than polyester may be mixed with the polyester sheet, and polyester should just contain more than 50 mass% among resin which comprises a sheet | seat.

  Although the thickness of the 2nd resin sheet 151 is not specifically limited, For example, it is 25 micrometers or more and 500 micrometers or less. The tear strength of the second resin sheet 151 by the Elmendorf tear method is not particularly limited, but may be, for example, 5 mN or more, 100 mN or more, preferably 10 mN or more, and more preferably 15 mN or more. Further, the breaking strength of the second resin sheet 151 is not particularly limited. For example, the breaking strength at a thickness of 25 μm may be 15 MPa or more, preferably 80 MPa or more, and more preferably 200 MPa or more. . The breaking elongation at a thickness of 25 μm of the second resin sheet 151 is 20% or more, preferably 70% or more, and more preferably 100% or more.

  Although not shown, the second resin sheet 151 may include a light regular reflection layer having a transparent resin film or a transparent metal film on the surface opposite to the surface on which the first resin sheet is disposed. This is because the glossiness of the light reflecting member 15 can be further improved. Examples of the transparent resin film for the light regular reflection layer include acrylic and polyester, and examples of the transparent metal film for the light regular reflection layer include silver, aluminum oxide, silicon oxide, tin-doped indium oxide, and antimony-doped tin oxide. The thickness of the light regular reflection layer is not particularly limited, but is 0.1 μm or more and 20 μm or less, and preferably 0.5 μm or more and 5 μm or less. Examples of the method of creating the light regular reflection layer include a method of coating the second resin sheet 151 with a composition having a transparent resin or a precursor thereof. Or the method of vapor-depositing a transparent metal and its precursor on the 2nd resin sheet 151 can be mentioned.

  The light reflectance of the light reflecting member 15 at a predetermined wavelength in the range of 450 nm to 650 nm is not particularly limited, but is 80% or more when measured from the first surface side of the first resin sheet 150. Is preferably 90% or more, and more preferably 95% or more. Although an upper limit is not specifically limited, For example, it is 110%.

  The value of the glossiness of the light reflecting member 15 is not particularly limited, but is preferably 70 or more and 80 or more when measured from the first surface side of the first resin sheet 150 at an incident angle of 60 degrees. Is more preferable, and 90 or more is more preferable. In addition, although an upper limit is not specifically limited, For example, it is 110 or less.

  The arithmetic average roughness (Ra) of the surface of the first light reflecting member 15 is not particularly limited, but is preferably less than 600 nm and less than 400 nm when measured from the first surface side of the first resin sheet 150. More preferably, it is less than 200 nm. It is for showing a favorable glossiness. In addition, although a minimum is not specifically limited, For example, it is 1 nm or more. In the present embodiment, the arithmetic mean roughness (Ra) of the surface is measured based on JIS B0601: 2013 “Product Geometric Specification (GPS) —Surface Property: Contour Curve Method—Terminology, Definition, and Surface Property Parameter”. can do. Specifically, it can be measured with a white interference type surface shape measuring microscope (New View 6300 manufactured by Zygo).

  The thickness of the light reflecting member 15 is not particularly limited because it varies depending on the application, but is, for example, 50 μm or more and 1 mm or less. The tear strength of the light reflecting member 15 by the Elmendorf tear method is not particularly limited, but may be, for example, 10 mN or more and 100 mN or less, preferably 15 mN or more, and more preferably 20 mN or more. The tensile strength of the light reflecting member 15 is not particularly limited, but is preferably 50 MPa or more. When the porous first resin sheet used for the light reflecting member 15 is a stretched film, the tensile force of the light reflecting member 15 in the flow direction (MD) and the width direction (TD) of the porous first resin sheet. The strength is preferably 50 MP or more.

The volume resistivity of the material constituting the light reflecting member 15 is not particularly limited, but is preferably 10 ¹⁴ Ω · cm or more, and more preferably 10 ¹⁸ Ω · cm or more. This is because, in particular, when the LED mounting substrate is disposed so as to cover the surface, a certain insulating property may be required.

  The light emitting member 15 can be obtained by a step of disposing a dense second resin sheet 151 on one surface side of the porous first resin sheet 150.

  FIG. 4 shows another embodiment of the light reflecting member 15. The light reflecting member 15 shown in FIG. 4 has a through hole 152 penetrating from one surface of the light reflecting member 15 to the other surface. In addition, the 2nd resin sheet and the 1st resin sheet are the same as that of embodiment shown in FIG. 3 mentioned above.

  The through hole 152 of the light reflecting member 15 plays a role of passing light emitted from the LED. Alternatively, as shown in FIG. 2, the LED 20 may be disposed in the through hole 152. The size of the through hole 152 varies depending on the application and the size of the LED and is not particularly limited, but is, for example, 0.1 mm or more and 100 mm or less. The number of through holes 152 varies depending on the application and is not particularly limited, and may be one or more.

  FIG. 5 shows another embodiment of the light reflecting member 15. The light reflecting member 15 shown in FIG. 5 is disposed on the second surface side of the first resin sheet 150, that is, on the surface side opposite to the surface on which the second resin sheet 151 of the first resin sheet 150 is disposed. A third resin sheet 153 is provided. The third resin sheet 153 and the first resin sheet 150 are joined with an adhesive (not shown). In addition, the 1st resin sheet 150 and the 2nd resin sheet 151 are the same as that of embodiment shown in FIG. 3 mentioned above, and the through-hole 152 is the same as that of embodiment shown in FIG. 4 mentioned above.

  The light reflecting member 15 illustrated in FIG. 5 includes a third resin sheet 153. Since the porous first resin sheet 150 and the dense second resin sheet 151 are greatly different in mechanical properties with respect to force and heat, the resin sheet is laminated only on one surface side of the first resin sheet 150. Only the light reflection member 15 may curl. In particular, since the light reflecting member 15 of the present embodiment is used in an LED mounting module, each sheet may contract under the influence of heat generated from the LED. By additionally disposing the third resin sheet 153, resin sheets are respectively disposed on both sides of the first resin sheet 150, and curling of the light reflecting member 15 can be suppressed.

  Specific examples of the resin used in the third resin sheet 153 include polyimide such as polyimide, polynylon, polyethylene naphthalate and polyethylene terephthalate, and polyolefin such as polyethylene and polypropylene. The third resin sheet 153 is preferably a resin sheet having a melting point of 180 ° C. or higher. This is because durability against heat generated from the LED can be imparted. A polyester sheet such as a polyethylene naphthalate sheet or a polyethylene terephthalate sheet is suitable as the third resin sheet 152 because of its relatively high heat resistance and excellent mechanical properties such as tensile strength and elongation at break. In addition, resin other than polyester may be mixed with the polyester sheet, and polyester should just contain more than 50 mass% among resin which comprises a sheet | seat.

  The third resin sheet 153 preferably includes the same type of resin as that contained in the second resin sheet 151. This is because the mechanical properties with respect to force and heat are approximate, and curling can be suppressed more easily. For example, when the second resin sheet 151 is a polyester sheet, the third resin sheet 153 is also preferably a polyester sheet.

  The third resin sheet 153 may be dense or porous. When the third resin sheet 153 is a dense resin sheet, the glossiness can be improved while curling is suppressed. When the third resin sheet 153 is a porous resin sheet, the light reflectivity can be improved while curling is suppressed.

  The thickness of the third resin sheet 153 is not particularly limited, but when the third resin sheet 153 is dense in order to bring close mechanical properties to force and heat, the thickness of the second resin sheet 151 is It may be 0.5 or more and 1.5 or less. When the third resin sheet 153 is porous, it may be 1.5 times or more and 5 times or less with respect to the thickness of the second resin sheet 151.

  FIG. 6 shows another embodiment of the light reflecting member 15. The light reflecting member 15 shown in FIG. 6 has a light reflecting layer 154 having a plurality of light reflecting particles and a resin binder for holding the plurality of light reflecting particles between the first resin sheet 150 and the second resin sheet 151. Is arranged. The light reflecting layer 154 may be disposed between the first resin sheet 150 and the third resin sheet 153. In FIG. 6, the 1st resin sheet 150 and the 2nd light reflection layer 154 are joined directly, and the 2nd light reflection layer 154 and the 2nd resin sheet 151 are joined by the adhesive agent (not shown). In addition, the 1st resin sheet 150, the 2nd resin sheet 151, the through-hole 152, and the 3rd resin sheet 153 are the same as that of embodiment shown in FIG. 5 mentioned above.

  By combining the first resin sheet 150 that is a porous resin sheet and the light reflecting layer 154 that is a layer having a plurality of light reflecting particles, the light reflecting performance can be improved. However, since these have many voids and many particles in the interior, the glossiness tends to decrease with these alone. Therefore, the light reflecting member 15 shown in FIG. 6 has a good glossiness because the dense second resin sheet 151 is disposed on the first resin sheet 150 and the light reflecting layer 154.

  In addition, when only one of the porous resin sheet having a plurality of voids therein or the layer having a plurality of light reflecting particles is used in the light reflecting member, generally, the thickness is increased, It is necessary to improve the light reflection performance. On the other hand, the light reflecting member 15 shown in FIG. 6 has a porous resin sheet having a different light reflecting mechanism and a layer having a plurality of light reflecting particles. Therefore, even if the thickness of each is relatively small, Excellent light reflection performance can be obtained. However, the porous resin sheet having a plurality of voids inside and a layer having a plurality of light reflecting particles tend to be fragile as a single unit because there are many voids and many particles inside. There is concern about durability and workability. Further, when these layers having greatly different mechanical properties such as flexibility are laminated, peeling or breakage between layers is likely to occur, and durability and workability may be further deteriorated. Therefore, the light reflecting member 15 shown in FIG. 6 exhibits good durability and workability because the dense second resin sheet 151 is disposed on the first resin sheet 150 and the light reflecting layer 154. The light reflecting member 15 shown in FIG. 6 is also durable in that a porous resin sheet and a layer having a plurality of light reflecting particles are disposed between the second resin sheet 151 and the third resin sheet 153. This contributes to improving the workability and workability.

  The light reflecting layer 154 has a plurality of light reflecting particles and a resin binder for holding the plurality of light reflecting particles. Examples of the light reflecting particles include titanium oxide, aluminum oxide, silica oxide, calcium carbonate, and barium sulfate, and titanium oxide is more preferable. Examples of the resin binder include polyurethane, polyester, and acrylic. The mass ratio between the light reflecting particles and the resin binder in the second light reflecting layer (the weight of the light reflecting particles / the weight of the resin binder) is not particularly limited, but is, for example, 1 or more and 25 or less.

  The thickness of the light reflection layer 154 is not particularly limited, but is 0.1 μm or more and 20 μm or less, and preferably 0.5 μm or more and 5 μm or less.

  Examples of the method for creating the light reflecting layer 154 include a method of coating the first resin sheet 150 with a composition having a plurality of light reflecting particles and a resin binder.

  Although not shown, a fourth resin sheet may be disposed between the second light reflecting layer 154 and the first resin sheet 150. This is because the durability and workability of the light reflecting member 15 are further improved. As a 4th resin sheet, the thing similar to the 3rd resin sheet 153 can be used. When using a 4th resin sheet, after creating the light reflection layer 154 on a 4th resin sheet, you may join with the 1st resin sheet 150 with an adhesive agent.

  The light reflecting member 15 described above can be suitably used as a light reflecting member for an LED mounting module. This is because the front luminance of the LED mounting module 1 can be improved.

  The LED mounting module 1 of this embodiment can be used as a light source of a display device or a lighting device.

  The LED mounting module of the embodiment shown in FIG. 1 and FIG. 2 described above can be suitably used as a direct light source. On the other hand, the LED mounting module of another embodiment shown in FIG. 7 can be suitably used as an edge light type light source. In FIG. 15, the LED mounting module 1 is disposed on the LED mounting substrate 10 and at least one surface side of the LED mounting substrate 10, the LED 20 and either surface is disposed facing the LED. The light guide member 30 and the light reflecting member 15 disposed on a surface side different from the surface facing the LED 20 of the light guide member 30 are provided. Although not shown, the light guide member 30 is on the second surface side of the first resin sheet 150 of the light reflecting member 15, that is, the surface opposite to the surface on which the second resin sheet 151 of the first resin sheet 150 is disposed. Arranged on the side. The light reflecting member 15 and the like are the same as those described in the LED mounting module of FIGS. For example, the light reflecting member 15 shown in FIGS. 3 to 6 can be used.

  The light emitted from the LED 20 disposed on the LED mounting substrate 10 enters the light guide member 30 and passes through, for example, a light reflecting dot (illustrated) disposed between the light guide member 30 and the light reflecting member 15. Is not gradually emitted from the surface of the light guide member 30. In FIG. 7, the surface of the light guide member 30 from which light is emitted (hereinafter sometimes referred to as “light emitting surface”) is the opposite surface of the light guide member 30 that faces the light reflecting member 15. The light reflecting member 15 can suppress unintentional emission of light from other than the light emission surface. Although not shown, the light reflecting member 15 having a plurality of through holes 152 can be used as a light reflecting dot. In FIG. 15, the light reflecting member 15 is disposed so as to face the light emitting surface of the light guide member 30, but is not limited thereto. Although not shown, the light reflecting member 15 is arranged to face the opposite surface of the light guide member 30 facing the LED 20, thereby suppressing unintentional emission of light from the surface. In addition, although not shown, the light reflecting member 15 is disposed to face a part of the light emitting surface of the light guide member 3, thereby controlling a region where light on the light emitting surface of the light guide member 30 is emitted. Can do.

  Further, the LED mounting module 1 of another embodiment shown in FIG. 8 includes an LED mounting substrate 10, an LED 20 disposed on at least one surface side of the LED mounting substrate 10, and the LED 20 of the LED mounting substrate 10. A light reflecting member 15 is provided on the same surface side as the surface on which the light reflecting member 15 is disposed. As the light reflecting member 15, for example, those shown in FIGS. 3 to 6 can be used. Since the light reflecting member 15 includes the second resin sheet 151, even if the light reflecting member 15 is disposed away from the LED mounting substrate 10, the light reflecting member 15 is difficult to curl due to its own weight. Although the thickness of the light reflection member 15 of this embodiment is not specifically limited, It is preferable that it is 200 micrometers or more and 1 mm or less. A gap is formed between the light reflecting member 15 and the LED mounting substrate 10. The gap in FIG. 8 is filled with air, but may be filled with an inert gas such as nitrogen or a rare gas, or a transparent material such as a polymer or glass.

  In FIG. 8, the light reflecting member 15 has a plurality of through holes 152 penetrating from one surface of the light reflecting member 15 to the other surface. The plurality of through-holes 152 are the size of the through-hole farther from the center point in the plane of the light reflecting member 15 with the intersection of the perpendicular line from the LED 20 toward the light reflecting member 15 and the light reflecting member 15 as the center point. However, it arrange | positions so that it may become larger than the magnitude | size of the through-hole of the one near a center point. The light reflecting member 15 only needs to have a plurality of light transmitting portions, and the plurality of light transmitting portions are not limited to the plurality of through holes 152. For example, you may have a transparent material in the position of the several through-hole of FIG.

  In FIG. 8, the light transmission diffusion member 16 is disposed opposite to the surface on which the LED mounting substrate 10 of the light reflecting member 15 is disposed so as to face the first light reflecting member 15 and away from it. Yes. As the light transmissive diffusing member 16, for example, a material having a light transmittance of 20% to 50% and a light reflectance of 50% to 80% can be used. Specifically, a resin sheet in which a large number of particles are contained in a transparent resin can be used. Further, the first light reflecting member 15 and the light transmission diffusion member 16 are fixed at desired positions by a fixing member 17. The fixing member 18 is, for example, a columnar pin that extends in the normal direction of the surface of the first light reflecting member 15. The LED mounting module 1 is disposed on the same surface side as the surface on which the LED 20 of the LED mounting substrate 10 is disposed, and the surface of the LED mounting substrate 10 excluding the region where the LED 20 of the LED mounting substrate 10 is disposed. A second light reflecting member 18 is provided that covers at least a portion. The second light reflecting member 18 has a through hole 182, and the LED 20 is disposed in the through hole 182. The 2nd light reflection member 18 can use the thing similar to the light reflection member 15 mentioned above.

  The light emitted from the LED 20 is directed toward the light reflecting member 15, and a part of the light is reflected by the light reflecting member 15 toward the LED mounting substrate 10 and the second light reflecting member 18, and further for LED mounting. The light is reflected by the surface of the substrate 10 and the second light reflecting member 18 toward the light reflecting member 15. A part of the light directed toward the light reflecting member 15 is reflected by the light reflecting member 15. As described above, the light is reflected in the gap between the light reflecting member 15 and the LED mounting substrate 10 by repeating the reflection between the light reflecting member 15 or the second light reflecting member 18 and the LED mounting substrate 10. Thus, it spreads in a horizontal direction on the surface of the LED mounting substrate 10. That is, while the light spreads in the horizontal direction on the surface of the LED mounting substrate 10, a part of the light passes through the through hole 152 of the light reflecting member 15 and is emitted from the LED mounting module. Since the light emitted from the LED 20 can be spread and made uniform in the horizontal direction on the surface of the LED mounting substrate 10, the LED mounting module shown in FIG. 8 can suppress variations in the amount of light to be irradiated and the luminance. The light emitted from the LED 20 has strong directivity and directivity toward the center point, so that the size of the through hole 152 in the vicinity of the center point is relatively small and the distance from the center point increases. By increasing the size of the hole, it is possible to make the light emitted from the surface of the LED mounting module 1 more uniform.

  In order to increase the brightness of the LED mounting module of FIG. 8, it is important that the light reflecting member 15 reflects light not only on the surface on the LED mounting substrate 10 side but also on the opposite surface. This is because, for example, light may be incident from the side opposite to the LED mounting substrate 10 of the light reflecting member 15 due to the influence of a frame (not shown), the light transmission diffusing member 16, the fixing member 17, and the like. .

  The manufacturing method of the LED mounting module 1 includes a first step of preparing the LED mounting substrate 10, a second step of arranging the LEDs 20 on at least one surface side of the LED mounting substrate 10, and the LED 20 of the LED mounting substrate 10. A third step of disposing the light reflecting member 15 on the same surface side as the surface on which the light is disposed. The third step may be performed after the second step is performed, or the second step may be performed after the third step is performed.

  The first step is a step of preparing the LED mounting substrate 10. The LED mounting substrate 10 can be obtained by using a known substrate manufacturing method. The method for producing the substrate includes, for example, an etching technique. Specifically, first, a metal layer such as copper is disposed on the support. A mask patterned to cover the metal layer is disposed. The metal layer that is not covered with the mask is removed with an etching solution. Finally, the mask is removed with an alkaline solution.

  A 2nd process is a process of arrange | positioning LED20 to the board | substrate 10 for LED mounting. The LED 20 is electrically bonded to the wiring portion 12 of the LED mounting substrate 10 using a bonding agent or solder having a conductive material such as metal or conductive plastic.

  The third step is a step of arranging the light reflecting member 15 on the LED mounting substrate 10. The light reflecting member 15 can form the through hole 152 with a cutter or a laser as necessary. The through hole 152 may be formed before the LED mounting substrate 10 is disposed, or may be formed after the LED mounting substrate 10 is disposed. However, when this step is performed after the second step, which will be described later, since the LEDs 20 are already arranged, the through holes 152 are preferably formed before the LED mounting substrate 10 is arranged.

  A display device or a lighting device is a suitable application of the LED mounting module 1 described above. FIG. 9 is a schematic diagram of the display device 100. In the display device 100, the LED mounting module 1 is disposed on the back surface of the display panel 2. As described above, the LED mounting module 1 includes the LED mounting substrate 10, the LED 20, and the light reflecting member 15. On the back surface of the LED mounting module 1, a heat dissipating member 3 for discharging heat of the LED is disposed. Since the LED mounting module 1 described above exhibits good durability and good quality, it contributes to extending the life and quality of the display device and the lighting device.

  Hereinafter, the present disclosure will be described more specifically with reference examples. However, the present disclosure is not limited to the following reference examples.

<Preparation of porous resin sheet>
Propylene homopolymer (Nippon Polychem Co., Ltd., trade name “Novatech PP: MA-8”, melting point 164 ° C.) 65.5% by mass, high density polyethylene (Nippon Polychem Co., Ltd., trade name “Novatech HD: HJ580 ”, melting point 134 ° C., density 0.960 g / cm ³ ) 6.5% by mass, and a composition for an inner layer having an average particle size of 1.5 μm and 28% by mass of calcium carbonate powder. An unstretched sheet was obtained. This unstretched sheet was stretched 4 times in the flow direction (MD) to obtain a uniaxially stretched sheet. In this reference example, the flow direction (MD) means the extrusion direction when the composition is extruded using an extruder.

Propylene homopolymer (manufactured by Nippon Polychem Co., Ltd., trade name “Novatech PP: MA-8”, melting point 164 ° C.) 51.5% by mass, high density polyethylene (manufactured by Nippon Polychem Co., Ltd., trade name “Novatech HD: HJ580 ”, melting point 134 ° C., density 0.960 g / cm ³ ) 3.5% by mass, calcium carbonate powder having an average particle size of 1.5 μm 42% by mass, titanium oxide powder having an average particle size of 0.8 μm 3% by mass The composition for the outer layer having, is extruded using a die on both sides of the uniaxially stretched sheet obtained above using an extruder to obtain a laminated sheet having a three-layer structure (outer layer, inner layer, and outer layer). It was.

  By stretching the laminate in the width direction (direction orthogonal to the flow direction of the uniaxially stretched sheet laminated on the inner layer, TD), the total thickness is 145 μm (outer layer 31 μm, inner layer 83 μm, outer layer 31 μm). A porous resin sheet was obtained. The porosity of the porous resin sheet was 55%.

<Reference Example 1>
Polyurethane adhesives (main agent Adlock RU-77T manufactured by Rock Paint, hardener lock bond JH-7 manufactured by Rock Paint, main agent: curing agent, respectively, on both surfaces of the porous resin sheet (first resin sheet 150) described above = 10: 1), polyethylene terephthalate sheets (thickness: 188 μm, Lumirror manufactured by Toray Industries, Inc.), which are dense resin sheets (second resin sheet 151, third resin sheet 153), were joined one by one. Thereby, the light reflecting member of Reference Example 1 was obtained.

<Reference Example 2>
The light reflecting member of Reference Example 2 was obtained using only the porous resin sheet described above.

<Evaluation of light reflecting member>
The light reflecting member of Reference Example 1 had a light reflectance of 99% at a wavelength of 560 nm, a glossiness of 95 at an incident angle of 60 degrees, and an arithmetic average roughness of the surface of 30 nm. In contrast, the light reflecting member of Reference Example 2 had a light reflectance of 100% at a wavelength of 560 nm, a glossiness of 36 at an incident angle of 60 degrees, and an arithmetic average roughness of the surface of 600 nm. The glossiness of the light reflecting member of Reference Example 1 including the porous resin sheet and the dense resin sheet was higher than that of the light reflecting member of Reference Example 2 having only the porous resin sheet.

  Each of the light reflecting members of Reference Example 1 and Reference Example 2 was bent, and the vicinity of the bent portion was visually observed. In contrast to the bent portion of the light reflecting member of Reference Example 2, a strong trace of bending was observed, whereas in the vicinity of the bent portion of the light reflecting member of Reference Example 1, the bent mark was observed. Was seen relatively weak. Therefore, it turned out that the light reflection member of the reference example 1 shows favorable durability.

  The light reflecting members of Reference Example 1 and Reference Example 2 were each cut with a cutter knife, and the vicinity of the cut site was visually observed. While many burrs were observed in the vicinity of the cut portion of the light reflecting member of Reference Example 2, there were relatively few burrs in the vicinity of the cut portion of the light reflecting member of Reference Example 1. Therefore, it turned out that the light reflection member of the reference example 1 shows favorable workability.

DESCRIPTION OF SYMBOLS 1 LED mounting module 10 LED mounting board 11 Support body 12 Wiring part 13 Conductive junction part 14 Insulation protection part 15 Light reflection member 150 1st resin sheet 151 2nd resin sheet 152 Through-hole 153 3rd resin sheet 154 Light reflection Layer 16 Light transmissive diffusing member 17 Fixing member 18 Second light reflecting member 182 Through hole 20 LED
30 Light Guide Member 2 Display Panel 3 Heat Dissipation Member 100 Display Device

Claims (16)

A light emitting diode mounting module,
The light emitting diode mounting module is
A light emitting diode mounting substrate;
A light emitting diode disposed on at least one surface side of the light emitting diode mounting substrate; and
A light reflecting member disposed on the same surface side as the surface on which the light emitting diode is disposed of the light emitting diode mounting substrate, and
The light reflecting member is
A porous first resin sheet having a first surface and a second surface opposite to the first surface;
A dense second resin sheet disposed on the first surface side of the porous resin sheet,
The light emitting diode mounting substrate is disposed on the second surface side of the first resin sheet of the light reflecting member,
Light emitting diode mounting module.   2. The light emitting diode mounting module according to claim 1, wherein the light reflecting member covers a part or all of a surface of the light emitting diode mounting substrate excluding a region where the light emitting diode is disposed on the light emitting diode mounting substrate.   The light emitting diode mounting module according to claim 1, wherein the light reflecting member is disposed facing and away from the light emitting diode. A light emitting diode mounting module,
The light emitting diode mounting module is
A light emitting diode mounting substrate;
A light emitting diode disposed on at least one surface side of the light emitting diode mounting substrate; and
A light guide member, any surface of which is disposed to face the light emitting diode;
A light reflecting member disposed on a surface side different from the surface facing the light emitting diode of the light guide member,
The light reflecting member is
A porous first resin sheet having a first surface and a second surface opposite to the first surface;
A dense second resin sheet disposed on the first surface side of the first resin sheet,
The light guide member is disposed on the second surface side of the first resin sheet of the light reflecting member,
Light emitting diode mounting module.   The light emitting diode mounting module according to any one of claims 1 to 4, further comprising a third resin sheet disposed on a second surface side of the first resin sheet.   The light emitting diode mounting according to any one of claims 1 to 5, wherein a glossiness at an incident angle of 60 degrees measured from the first surface side of the first resin sheet of the light reflecting member is 70 or more. module.   The light emitting diode mounting module according to any one of claims 1 to 6, wherein the first resin sheet of the light reflecting member is a porous polyolefin sheet.   The light emitting diode mounting module according to any one of claims 1 to 7, wherein a porosity of the first resin sheet of the light reflecting member is 25% or more and 80% or less.   The light emitting diode mounting module according to any one of claims 1 to 8, wherein the second resin sheet of the light reflecting member is a polyester sheet.   The light emitting diode mounting module according to any one of claims 1 to 9, wherein the third resin sheet of the light reflecting member includes the same type of resin as the resin included in the second resin sheet.   The light emitting diode mounting module according to any one of claims 1 to 10, wherein the third resin sheet of the light reflecting member is a polyester sheet.   The light reflection member arrange | positioned at the light emitting diode mounting module as described in any one of Claims 1-11. A porous first resin sheet having a first surface and a second surface opposite to the first surface;
A dense second resin sheet disposed on the first surface side of the first resin sheet,
Light reflecting member for light emitting diode mounting module.   14. The light reflection module for light emitting diode mounting module according to claim 13, wherein the light reflection member for light emitting diode mounting module has a glossiness at an incident angle of 60 degrees measured from the first surface side of the first resin sheet of 70 or more. Element.   A display device comprising the light emitting diode mounting module according to claim 1.   An illuminating device comprising the light emitting diode mounting module according to any one of claims 1 to 11.

Images