KR101062935B1 - Method of manufacturing circuit board for light emitting body, circuit board precursor for light emitting body, circuit board for light emitting body, and light emitting body - Google Patents

Abstract

SUMMARY OF THE INVENTION An object of the present invention is to form a recess having a bottom surface including a portion on which a light emitting element is mounted, and to achieve a light weight and thickness reduction, and a light emitting circuit board precursor and a recess having a light emitting circuit board and a manufacturing method thereof; And a light emitting body having a substrate on which recesses are formed. The method of manufacturing a light emitting circuit board according to the present invention includes at least one pair of electrode predetermined portions of a light emitting element on a surface of a liquid crystal polymer film, and each of the electrode predetermined portions is formed of a metal circuit pattern connected to another circuit in the substrate through a conductive circuit. And forming a recess having a bottom portion where the electrode predetermined portion and the conductive circuit should be present and a wall surface on which the conductive circuit should exist at a portion including the electrode predetermined portion. .

Circuit boards, precursors, light emitters

Description

TECHNICAL METHOD OF CIRCUIT BOARD FOR LIGHT EMITTING BODY, PRECURSOR OF CIRCUIT BOARD FOR LIGHT EMITTING BODY, CIRCUIT BOARD FOR LIGHT EMITTING BODY, AND LIGHT EMITTING BODY}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a circuit board for mounting a light emitting element to form a light emitting body, a precursor of the circuit board, the circuit board, and a light emitting body. In addition, in this specification, a "light emitting circuit board" refers to a circuit board for making a light emitting body by mounting a light emitting element, and a "light emitting circuit board precursor" refers to forming a main part on which a light emitting element is mounted in three dimensions. By this, the light emitting circuit board is referred to. "Light emitting element" means a light emitting material (semiconductor material) itself such as GaAlAs, and "light emitting element" refers to an object obtained by die-bonding the light emitting element to an electrode part of a circuit board and sealing with a transparent resin (light emitting diode) Or LED). In addition, chip LED means LED manufactured as a chip component.

As a manufacturing method of the so-called chip LED which mounted the light emitting element, it was as follows conventionally. (i) Holes are punched in each part of the continuous lead frame by a method such as punching or etching, and a casing made of heat-resistant thermoplastic resin is formed therein by injection molding (insert molding). (ii) A light emitting element is provided in this case portion using a die bonding paste or the like, and is connected to an external circuit by connecting the light emitting element to another electrode by wire bonding, and then emitting the light using a transparent sealing resin. Environmentally isolate the device parts. (iii) Separate the product into individual chip LEDs. Moreover, in order to improve handleability, the tape-shaped case made of embossed plastic is separately prepared, chip LEDs are inserted one by one, and sealed in a tape. In addition, it may be a product in the form wound up for use in the subsequent continuous line.

However, in the said manufacturing method, adhesiveness of a lead frame and a thermoplastic resin case is not favorable, and there existed a problem which a sealing resin leaks from these interfaces. Moreover, the manufacturing process became complicated in that insert molding was performed, and the productivity was not good. In addition, when the product is manufactured in the form inserted into a tape-shaped case as described above, this case is discarded, and there is a problem in that unnecessary cost and waste are generated.

In order to solve the above problems associated with the manufacture of chip LEDs, various techniques have been proposed. For example, Japanese Patent Laid-Open No. H01-283883 discloses a chip LED in which a plated electrode portion of a three-dimensional pattern is provided on its concave surface of a reflective case having a concave surface, and a light emitting element is mounted on this electrode portion. According to this technique, this technique can reduce the manufacturing cost and solve the sealing resin leakage between the lead frame and the reflective case as compared with the conventional chip LED by the insert molding method.

In Japanese Unexamined Patent Publication No. H06-350206, a circuit pattern made of a conductive material is formed on the surface of the primary molded body including the interface between the primary molded body and the secondary molded body which is molded by insert molding and integrated into the secondary molded body. In the absence of, a three-dimensional circuit board formed by exposing a part of the circuit pattern is proposed. In Japanese Unexamined Patent Application Publication No. H06-350206, in order to perform plating on almost the entire surface side of the circuit board with respect to the technique of Japanese Unexamined Patent Publication No. H01-283883, the cost tends to increase in proportion to the plating area. In addition, the electrode pattern of the part not covered with the sealing resin is exposed in the finished product after mounting the light emitting element, and therefore, it is pointed out that the electrode pattern may be damaged during handling or installation of the light emitting element, resulting in disconnection of the electrode pattern. . According to the technique disclosed in Japanese Laid-Open Patent Publication No. H06-350206, since the main part of the circuit pattern can be protected by the secondary molded body, problems such as disconnection of the electrode pattern can be avoided, and the plating area can be increased. The problem of cost by this can also be solved by specifying the resin used for a secondary molded object.

On the other hand, circuit boards for LEDs based on metal cores (metal plates) have also been proposed (for example, Japanese Patent Application Laid-Open No. H11-54863, Japanese Patent Application Laid-Open No. H11-204904 and Japanese Patent Application Laid-Open No. H11-298050). ). In these circuit boards, after the printed circuit is formed on the surface of the insulating layer (heat-resistant thermoplastic resin layer) provided on the metal core, concave portions (the recesses) are formed by die fitting of male and female. In these publications, in order to prevent the damage of the printed circuit at the time of formation of this recessed part, the technique which studies shaping | molding angle etc. is disclosed.

In addition, as a technique for preventing breakage of the circuit during molding, there is a technique described in Japanese Patent Laid-Open No. H03-204979. According to this technique, the stress between the solar cell elements when the solar cell module is deformed by connecting the solar cell elements with the inner lead is said to be absorbed.

Also, Japanese Laid-Open Patent Publication No. H05-283849 discloses a technique for preventing the cutting of a conductive circuit and the like during uneven shaping in the manufacturing method of a three-dimensional molded circuit board. Specifically, the circuit is transferred to a thermoplastic resin to form a primary molded circuit board, and then the unevenness is shaped after heating the deformed portion or before the injection molded primary molded circuit board is cooled.

In addition, Japanese Laid-Open Patent Publication No. H11-307904 describes a method of integrating a wiring sheet in which a wiring pattern is formed in advance during the molding of a three-dimensional molded body made of resin.

However, according to the technique of Japanese Unexamined Patent Publication No. H06-350206, since it is necessary to integrate the primary molded body and the secondary molded body by the insert molding method, the productivity of Japanese Unexamined Patent Publication No. H01-283883 has been a problem. The improvement was unresolved.

Moreover, as a problem common to the technique of JP H01-283883 and JP H06-350206, there is a fact that the step of providing a circuit pattern on a substrate on which a light emitting element is provided is after molding of the substrate. . As a result, a circuit pattern must be formed in accordance with the complicated shape after molding, and this operation is very difficult. In addition to the plating method (electroless plating method) disclosed in these publications, there is a circuit pattern forming method by transfer, but it is also difficult to form a circuit pattern on a substrate after molding, and it is difficult to form a pattern with high accuracy especially in a fine circuit. Do.

On the other hand, in the technique of Japanese Patent Laid-Open No. H11-54863, since a method of forming recesses after adopting a circuit pattern in advance is adopted, relatively high degree of pattern formation becomes possible. However, the circuit board disclosed in these documents is a metal substrate provided with an insulating layer substantially, and has the following problems. Since the metal core used by the technique of these publications is thick as thickness: 0.6-1.2 mm, the thickness and weight of a chip LED will increase. In addition, even when attempting to form recesses for small chip LEDs, the metal core is thick, and therefore, recesses having a small and sharp shape cannot be formed.

Moreover, also in the technique of Unexamined-Japanese-Patent No. H05-283849, shaping | molding is carried out after previously transferring a circuit to thermoplastic resins, such as polybutylene terephthalate (PBT). However, the technique cannot be applied to liquid crystal polymer films. In this technique, cutting of the circuit at the time of uneven | corrugated molding etc. is prevented by heating a deformation | transformation part, or shaping | molding before resin cools. By the way, not only the cost for the heating means is required, but also in the liquid crystal polymer film, the timing is very difficult to be molded to the extent that deformation can be maintained while maintaining the overall shape. In practice, only the PBT is exemplified in the publication as a circuit board material, and there is no description of the liquid crystal polymer film.

In the technique of Japanese Patent Application Laid-Open No. H03-204979, disconnection at the time of deformation is prevented by connecting the elements with inner leads, but only the process of connecting the elements in sequence is necessary. It is not suitable for synthesis. Again, if the goal is mass synthesis, the circuit should be printed on a flat plate.

In addition, in the technique of JP H11-307904, the molded part is formed after the wiring pattern is formed on the liquid crystal polymer film, but problems such as disconnection occurring when deformation occurs in the range including the wiring pattern are not recognized at all. . Referring to the drawings attached to this publication, the wiring pattern exists only at a position without accompanying deformation.

In recent years, there is a request for downsizing of a light emitting body using LEDs (backlight of a liquid crystal monitor of a mobile phone). However, in circuit boards such as Japanese Patent Application Laid-Open No. H11-54863, which are metal substrates (metal core substrates), the chip LED has a smaller size in terms of weight and thickness increase, and further, moldability (formability to sharp shapes) of recesses. You cannot respond enough to the request. Moreover, it is very disadvantageous compared with using a film resin as a board | substrate, for example, it cannot be made into the flexible tape-shaped product used as a reel winding in order to improve handleability.

In addition, from the viewpoint of increasing the efficiency of production of the circuit board, it is preferable to continuously manufacture a long circuit board having a plurality of portions on which the light emitting element should be mounted. This is because the circuit pattern can be applied to a long one, and even when a short circuit pattern is manufactured, it can be used after cutting continuously. In the case of manufacturing the light emitting body at a long length, productivity can be increased by continuously mounting the light emitting element at a design position on the circuit board. However, at this time, although a long circuit board is required to be wound and handled in roll shape, the circuit board disclosed by Unexamined-Japanese-Patent No. H11-54863 etc. is flexible in order to have a metal plate core of thickness close to 1 mm. Because of this lack, it is impossible to wind the roll in a normal curvature. Even in the technique of JP H05-283849, the circuit board must be thickened to some extent, and continuous manufacturing is difficult in the method of forming the uneven portion while injection molding.

The present invention has been made in view of the above circumstances, and an object thereof is to form a recess having a bottom including a portion on which a light emitting element is mounted, and to provide a light-emitting circuit board precursor and a recess that can achieve weight reduction and thinning. The present invention provides a light emitting body comprising a light emitting circuit board having a light emitting element, a manufacturing method thereof, and a substrate on which recesses are formed.

Method of manufacturing a circuit board for a light emitting body according to the present invention that can achieve the above object,

A step of forming a metal circuit pattern having at least one pair of electrode predetermined portions of the light emitting element on the surface of the liquid crystal polymer film, and each of the electrode predetermined portions connected to another circuit in the substrate via a conductive circuit (hereinafter, "a circuit pattern forming process. '', And

The process of forming the recessed part which has the said electrode predetermined part and the bottom part which the said conductive circuit should exist, and the wall surface which the said conductive circuit should exist in the site | part containing this electrode predetermined part (henceforth a "recess part formation process"). It characterized in that it comprises a). Here, "connected with the other circuit in a board | substrate" includes the form connected with the part which can be connected with the external circuit among board | substrates.

In the circuit board precursor for the light-emitting body of the present invention, a circuit pattern made of metal is formed on the surface of the liquid crystal polymer film.

In the circuit pattern, at least one pair of electrode predetermined portions on which the light emitting element is to be mounted exists, and each of the electrode predetermined portions is connected to another circuit in the substrate through a conductive circuit.

It is characterized in that it is used to form the recessed part which has the electrode predetermined part and the bottom part which the said conductive circuit should exist in, and the wall surface which the said conductive circuit should exist in the site | part containing this electrode predetermined part. The definition of "connected with another circuit in the substrate" is the same as that described above.

In the light emitting circuit board of the present invention, a recess in which the light emitting element is to be mounted is formed at a portion including the electrode predetermined portion of the light emitting circuit board precursor, and the conductive circuit is formed on the bottom and wall of the recess. It is characterized by the presence.

The light emitting body of the present invention is characterized by having a circuit board for the light emitting body.

In addition, the "film" said by this invention is a concept also containing what is called a sheet.

1 is a plan view showing an example of a circuit board precursor (flat plate) for a light-emitting body of the present invention.

Fig. 2 is a plan view showing an example of a circuit board precursor (flat plate) for a light-emitting body of the present invention in which a specific shape is given to a conductive circuit.

3 is a plan view illustrating a circuit board for a light-emitting body in which recesses are formed in the substrate of FIG. 2.

4 is a cross-sectional view taken along line II of FIG. 2.

5 is a cross-sectional view taken along the line II-II of FIG. 3.

Fig. 6 is a plan view showing another example of a circuit board precursor (flat plate) for a light-emitting body of the present invention in which a specific shape is given to a conductive circuit.

Fig. 7 is a plan view showing an example of a circuit board precursor for a light emitting body of the present invention used for a planar light emitting body.

8 is a cross-sectional view showing an example of the light emitting body of the present invention.

9 is a cross-sectional view showing an example of a light emitting body of the present invention having a heat dissipation means.

10 is a plan view showing an etching pattern of a substrate produced in the example.

FIG. 11 is an enlarged view of the recessed portion planning part of FIG. 10.

12 is a cross-sectional view showing the main portion shape of the substrate produced in the example, and is a cross-sectional view taken along the line II-II in FIG.

FIG. 13 is a plan view showing an etching pattern of a substrate precursor prepared in Experiment 3. FIG.

FIG. 14 is an enlarged view of the main portion forming scheduled portion of the substrate precursor (having slits in the conductive circuit) prepared in Experiment 3. FIG.

FIG. 15 is an enlarged view of the main portion formation scheduled portion of the substrate precursor (no slits in the conductive circuit) prepared in Experiment 3. FIG.

FIG. 16 is a substrate precursor prepared in Example 6, (a) an enlarged view of a planar portion-forming portion having a shape curved in plan view and having an elongation value of substantially radial symmetry at a center angle of 180 °; FIG. . The oblique line portion is an electrode portion (electrode predetermined portion) on which the light emitting element is to be mounted. (b) is sectional drawing in the AA 'direction of FIG. 16 (a) at the time of forming recessed part in the said substrate precursor. (c) is a bird's eye view of the relevant part. However, for convenience, the front circuit pattern is omitted, and the solid line portion shows the portion deformed at the time of recessed part formation, and the broken line portion shows the portion not deformed.

FIG. 17 is a main portion that is curved in a planar view and has a circuit having an elongation value of substantially radial symmetry at a center angle of 90 ° and capable of mounting a plurality of (2 or 3) light emitting elements. It is an enlarged view of a formation plan part.

Fig. 18 is an enlarged view of a recessed portion planning part which has a circuit shape curved in a planar view and has a circuit having an elongation value of substantially radial symmetry at a center angle of 120 ° and in which two light emitting elements can be mounted; .

19 is a diagram illustrating an example of a circuit diagram for displaying a letter of "8".

20 is an enlarged view of FIG. 19.

FIG. 21 is a view showing a circuit board precursor for a light-emitting body for a planar light-emitting body that uses the recessed portion formation scheduled portion of FIG. 16.

FIG. 22 is a view showing a planar light-emitting body produced using the circuit board precursor for the light-emitting body of FIG. 21.

23 is a view showing an example of a circuit board precursor for a light emitting body according to the present invention. Thus, after manufacturing a board | substrate precursor elongate, it can cut | disconnect suitably at arbitrary positions of a block unit, and can be used.

FIG. 24 is a view of the state when the surface light-emitting body of FIG. 22 is actually used from the back side. FIG.

Explanation of the sign

1: circuit board precursor for light emitter,

2: electrode scheduled portion,

3: conductive circuit,

4: other circuitry within the substrate,

5: liquid crystal polymer film,

6: sprocket,

7: slit,

8: bottom,

9: lumbar wall panel,

10: light emitting element,

11: wire bonding,

12: sealing resin,

13: luminous body,

14: heat sink,

15: refrigerant through hole,

16: guide hole

According to the method of manufacturing a light emitting circuit board according to the present invention, it is possible to achieve formation of fine and highly accurate circuit patterns, formation of recesses having portions on which the light emitting elements are to be mounted, and to further reduce the weight and thickness of the light emitting circuit board. Can be. In addition, the circuit board precursor for the light emitting body is useful as the manufacturing method according to the present invention and the manufacturing intermediate of the circuit board for the light emitting body. In addition, since the circuit board for the light-emitting body of the present invention can be a tape-like substrate, the light-emitting body can be continuously manufactured to improve the productivity of the light-emitting body, and the light-emitting inspection of the individual light-emitting bodies can be easily performed. In addition, the planar light emitting body and the display device can be easily manufactured.

As described above, the light emitting body of the present invention can be easily obtained in the form of a planar light emitting body or a display device and has the circuit board of the present invention composed of a thin liquid crystal polymer film. By providing the heat radiating means on the surface side, heat generated from the light emitting body can be efficiently removed through the liquid crystal polymer film.

In the present invention, in obtaining a circuit board for a light-emitting body having a recessed portion having a bottom surface including a portion on which a light emitting element is to be mounted (hereinafter sometimes referred to as a "light emitting element mounting portion"), it is composed of a liquid crystal polymer film. Moreover, it has the biggest characteristic in that recessed part formation is carried out using the flat-shaped light-emitting circuit board precursor in which the metal circuit pattern was previously formed.

As described above with respect to Japanese Laid-Open Patent Publication No. H01-283883, it is difficult to form a fine circuit pattern with high accuracy in the method of forming a circuit pattern on a substrate having recessed portions. Therefore, in the present invention, a circuit pattern is formed in advance on a flat substrate, and the circuit pattern is formed, whereby a fine and highly accurate circuit pattern can be formed.

Further, by constructing the substrate from the liquid crystal polymer film, a reinforcing metal plate different from the metal layer for forming the circuit pattern (a metal core such as the circuit board disclosed in JP-A-H11-54863, etc., in particular, about 0.6 to several mm in thickness) Without using a metal plate), the molding (formation of recesses) after the circuit pattern formation can be performed. As described above, in a circuit board using a thick metal core, such as Japanese Patent Application Laid-Open No. H11-54863 or the like, the increase in weight and the formability are inferior, and furthermore, it is rolled up into a roll as a long one due to the increase in thickness. It is disadvantageous in that it is impossible to handle. On the other hand, in the conventional resin substrate as in the circuit of JP H01-283883, the thickness of the resin portion is large and is not suitable for molding after circuit pattern formation. In addition, in the semiconductor field, a polyimide substrate is known as a film substrate (eg, TAB (Tape Automated Bonding) substrate), but since it is composed of a cured body of thermosetting polyimide, the main part of the substrate of the present invention Deformation with elongation, ie plastic deformation, is not practically possible.

In the case where the substrate is made of a thermoplastic resin film, there is a problem that the substrate is deformed due to heat such as soldering when the light emitting element is mounted. However, in the present invention, such a problem can be solved by selecting a liquid crystal polymer having excellent heat resistance. will be.

Moreover, in other heat resistant thermoplastic resins, such as a polyether ether ketone resin (PEEK resin), the linear expansion coefficient in resin alone is large, and deformation | transformation is easy to occur, when bonding with metal. In order to prevent this, filler filling, polymerization, etc. have been tried. However, these improved resins also have a disadvantage in that the fine moldability is poor. On the other hand, the liquid crystal polymer used in the present invention has a low coefficient of linear expansion and is excellent in fine formability.

Hereinafter, each structure of the board | substrate of this invention and the light-emitting body of this invention are demonstrated in detail.

<Liquid crystal polymer film>

The liquid crystal polymer constituting the liquid crystal polymer film is a heat resistant thermoplastic resin, for example, a thermotropic liquid crystal polymer exhibiting liquid crystallinity in a molten state. In this invention, a thermotropic liquid crystalline polymer is suitable, More specifically, a thermotropic liquid crystalline polyester and a thermotropic liquid crystalline polyesteramide are preferable.

Thermotropic liquid crystalline polyesters (hereinafter simply referred to as "liquid crystal polyesters") are aromatic polyesters synthesized mainly by monomers such as aromatic dicarboxylic acids and aromatic diols and aromatic hydrokisicarboxylic acids. It shows liquid crystallinity.

Representative examples thereof include a type I synthesized from parahydroxybenzoic acid (PHB), terephthalic acid, and 4,4'-biphenol (formula (1)), PHB and 2,6-hydroxynaphthoic acid. Type II [formula (2)], PHB, terephthalic acid, and type III [formula (3)] synthesize | combined from ethylene glycol are mentioned.

As liquid crystalline polyester, although it may be any of type I-III, all aromatic polyesters (type I and II) are preferable at the point of heat resistance and dimensional stability, and lead-free soldering (for example, at 260 degreeC) And liquid crystal polyester of type I is particularly preferable in that the main part moldability is also good.

Moreover, as a liquid crystal polymer which concerns on this invention, if it shows liquid crystalline (especially thermotropic liquid crystalline), the unit represented by said formula (1)-(3), for example, will mainly be a main body (for example, the whole structural unit of a liquid crystal polymer). 50 mol% or more), and may be a copolymer type polymer having other units. As another unit, the unit which has an ether bond, the unit which has an imide bond, the unit which has an amide bond, etc. are mentioned, for example.

In obtaining a liquid crystal polymer film, various well-known methods corresponding to resin which comprises this can be employ | adopted. Moreover, as a film using the liquid crystalline polyester of the said example suitable especially in this invention method, commercial items, such as "BlAC (trademark)" by the Japan Pangoretex Co., Ltd., can be used.

Moreover, the liquid crystal polyester amide corresponds to the said liquid crystal polyester which has an amide bond as another unit, For example, what has a structure of following formula (4) is mentioned. For example, in Formula (4), it is known that the molar ratio of the unit of s, the unit of t, and the unit of u is 70/15/15.

Moreover, the polymer alloy containing said liquid crystal polymer can be used for a liquid crystal polymer film. In this case, the polymer for alloy mixed or chemically bonded to the liquid crystal polymer may be a polymer having a melting point of 220 ° C. or higher, preferably 280 to 360 ° C., for example, polyetheretherketone, polyethersulfone, polyimide, polyetherimide, Although polyamide, polyamideimide, polyarylate, etc. are mentioned, It is not limited to these. Although the mixing ratio of a liquid crystal polymer and the said polymer for alloys is not specifically limited, For example, it is preferable that it is 10: 90-90: 10 by mass ratio, and it is more preferable that it is 30: 70-70: 30. Polymer alloys containing a liquid crystal polymer may also possess excellent properties by the liquid crystal polymer.

In the said liquid crystal polymer film, it is preferable that the linear expansion coefficient of the direction parallel to a film plane is adjusted to 25 ppm / degrees C or less. More preferably, it is 21 ppm / degrees C or less. Moreover, it is preferable that the minimum of the said linear expansion coefficient of a liquid crystal polymer film is 8 ppm / degreeC. The coefficient of linear expansion of the liquid crystal polymer film was measured by instrumental analysis (TMA), width of test piece: 4.5 mm, distance between chucks: 15 mm, load: 1 g, and after heating up from room temperature to 200 ° C (heating rate: 5 ° C / min). , Temperature-lowering rate: Value calculated from the dimensional change of the test piece measured between 160 ° C and 25 ° C when cooling at 5 ° C / min, for example, MD direction of film (traveling direction in film production) and TD direction All of the linear expansion coefficients in the direction orthogonal to the MD direction should satisfy the above range.

In the circuit board of the present invention, recesses are formed on flat plates provided with circuit patterns. When the thermoplastic film and the metal circuit bonded thereon are three-dimensionally formed together, when a large difference in coefficient of linear expansion is combined, defects such as warpage, torsion, and depression are likely to occur in the metal circuit portion on the film. In this case, the thickness and elastic modulus of the film and the metal may be different, but there is a fear of causing distortion and warpage even in the step of adhering the film and the metal.

For example, a circuit board having the same configuration as the present invention except that a polyetherimide film having a linear expansion coefficient of 56 ppm / ° C. is used instead of the liquid crystal polymer film that satisfies the linear expansion coefficient. When the recess is formed, the inventors have confirmed that the above-described partial warping, twisting, dents, and the like occur in the metal circuit portion on the polyetherimide film.

The coefficient of linear expansion of the metal suitable for the metal layer used for forming the circuit pattern is usually about 3 to 30 ppm / 占 폚 (for example, 16.2 ppm / 占 폚 for copper). Therefore, in the case of a liquid crystal polymer film having a linear expansion coefficient of less than or equal to the above upper limit, since the difference in the linear expansion coefficient with the metal layer is small, the occurrence of such defects in the exposed portion of the liquid crystal polymer film at the time of recessed formation is highly suppressed. However, it is preferable that the metal used by this invention selects the thing whose linear expansion coefficient is as close as possible to a liquid crystal polymer film.

In the liquid crystal polymer film, in order to adjust the linear expansion coefficient as described above, the polymer molecular chain in the film may be randomly oriented in the film plane direction. Specifically, a method of producing a uniaxially oriented film by the melt extrusion method and uniaxially stretching it in the TD direction or biaxially stretching in the MD direction and the TD direction can be adopted. Thus, the manufacturing method of the liquid crystal polymer film with which the linear expansion coefficient was adjusted is disclosed in detail in Unexamined-Japanese-Patent No. H10-294335.

Moreover, since the liquid crystal polymer film which concerns on this invention also plays the role as a case of a light emitting body, it is preferable to have the structure which can improve the reflectance of light and can take out the light emitted efficiently to the outside. Specifically, it is recommended that the liquid crystal polymer film has a color in which the reflectance of light, such as white or silver, is increased. In order to apply such a color to a liquid crystal polymer film, the method of film-forming, for example after kneading a coloring pigment (titanium oxide powder etc.) with a liquid crystal polymer can be employ | adopted.

Although the thickness of a liquid crystal polymer film can be suitably selected according to the size requested | required by a light emitting body, For example, it is 10 micrometers or more, More preferably, it is 50 micrometers or more, It is preferable to set it as 3 mm or less, More preferably, it is 1 mm or less. Do. If the thickness is too thin, cracks and wrinkles are likely to occur in the circuit board during the formation of recesses, and the practicality is lowered. On the other hand, if the thickness is too thick, the heat dissipation means is provided after forming the light emitting body (detailed later), and the arrangement efficiency at the time of excluding heat generated from the light emitting element through the liquid crystal polymer film is lowered. Since the effect (improvement in mechanical strength, etc.) obtained by thickening is saturated, unnecessary materials are used, which is disadvantageous in terms of cost and weight reduction. For example, for a small light emitting body such as a chip LED widely used conventionally, a thin liquid crystal polymer film (for example, about 200 µm or less) can be coped with in the above thickness. On the other hand, when the light emitting element mounting portion is applied to a relatively large LED having a diameter of 5 mm or more, it is recommended to use a slightly thick liquid crystal polymer film among the above ranges.

<Circuit pattern>

The circuit board precursor of the present invention or the circuit pattern according to the circuit board has at least one pair of electrode predetermined portions in the recessed portion formation scheduled portion serving as the light emitting element mounting portion, and has another circuit connected to the electrode predetermined portion. Here, "another circuit in a board | substrate" shall include the part of a board | substrate which can be connected with an external circuit. Circuits other than the above may be provided with portions for mounting electronic components other than the light emitting element. In the present invention, since the circuit pattern is formed on the planar liquid crystal polymer film and then three-dimensionally formed, it is more complicated than the prior art of forming the circuit pattern after the three-dimensional formation.

The circuit pattern is made of metal, and is formed by, for example, providing a metal layer on the surface of the liquid crystal polymer film and etching the metal layer. As a method of forming the metal layer, in addition to the method of adhering the liquid crystal polymer film and the metal plate (including metal foil, metal film, etc.), a method of forming the surface of the liquid crystal polymer film by vacuum deposition, sputtering, ion plating, plating, CVD, or the like It is also possible to employ.

As a method of adhering a liquid crystal polymer film and a metal plate, the thermal fusion method is suitable. As a thermal fusion method, the film lamination | stacking surface is heat-softened utilizing the thermoplasticity of a liquid crystal polymer, a metal plate is laminated | stacked on the surface, and it cools, or a liquid crystal polymer film and a metal plate are overlapped, and it is between a pair of rolls which heated this. The method of heat-sealing through and cooling after that, etc. can be employ | adopted.

Moreover, the adhesiveness of a liquid crystal polymer film and a circuit pattern can be improved further by using the thing which roughened the surface of the side which contact | connects the said liquid crystal polymer film of metal plates, such as a metal foil, at least. That is, when a circuit is formed by etching or the like after the metal foil or the like having a roughened surface is pressed onto the liquid crystal polymer film, the surface of the portion where the metal foil or the like has been removed is also roughened. As a result, adhesiveness with a sealing resin becomes high and a product defect can be reduced. The degree of roughening on the metal plate or liquid crystal polymer film surface for forming a circuit is not particularly limited, but may be, for example, about 1 to 15 µm at Rz. If Rz is 1 micrometer or more, an effect can be anticipated. Especially, when it is 8 micrometers or more, it is demonstrated that the adhesive force exceeding the copper foil surface is exhibited like Example 8 mentioned later.

There is no restriction | limiting in particular as a metal which comprises a metal layer, Alloy containing copper, aluminum, tin, silver, gold, platinum, zinc, iron, and these metals (stainless steel (SUS), a copper alloy for lead frames, 42 alloys (42% Ni-Fe alloy) etc. are mentioned. The metal layer may be a single layer structure or a laminated structure in which two or more kinds of metals are stacked. There is no particular limitation on the lamination method, for example, after the liquid crystal polymer film and the metal plate are adhered to each other, the metal plate is formed by a vacuum vapor deposition method, sputtering method, ion plating method, plating method, or CVD method. The method of providing the metal layer used, etc. can be employ | adopted. Although the metal which comprises a metal layer can be selected suitably according to the objective, For example, it is preferable from a viewpoint of a moldability improvement to select a thing whose linear expansion coefficient is close to the linear expansion coefficient of a liquid crystal polymer film.

The thickness of the metal layer for forming the electronic circuit in the present invention is, for example, 1 m or more, more preferably 5 m or more, preferably 500 m or less, and more preferably 50 m or less. When the thickness of the metal layer is too thin, in addition to the lack of reliability as a circuit, when forming recesses in the substrate, a slight tension may be applied. On the other hand, when the thickness of the metal layer is too thick, the formation of circuit patterns by etching or the like becomes difficult, and the moldability at the time of forming recesses in the substrate tends to be impaired.

A part of this metal layer is removed and a circuit pattern is formed. As the method, a known etching method is suitable. As the etching method, for example, a resist film formed with a pattern is formed on the surface of the metal layer so that a portion to be removed is exposed by a known photoresist method, and a liquid capable of dissolving the metal layer (e.g. A method of removing the resist film after dissolving and removing the exposed portion of the metal layer using a ferric aqueous solution or the like). There is no restriction | limiting in particular in the resist resin used for etching, the liquid solution of a metal layer, the removal liquid of a resist film, the formation conditions of a resist film, the melting condition of a metal layer, etc., It can select suitably according to the material of a metal layer and the circuit pattern to form.

The circuit pattern has a structure in which at least one pair of electrode predetermined portions are provided in the light emitting element mounting portion, and the electrode predetermined portions are connected to other circuits (including connection terminals for connecting with external circuits, etc.) in the substrate through conductive circuits, respectively. do. When forming the circuit which has such a connection terminal, in order to raise the mechanical strength in the said connection terminal part of the board | substrate of this invention, you may attach and reinforce a stiffener to a part of a circuit back surface as needed. As a material of this stiffener, a liquid crystal polymer, polyimide, or the like can be used. 1 shows an example of a circuit board precursor for a light-emitting body of the present invention. (1) is a circuit board precursor for a light-emitting body, (2) is an electrode predetermined portion, (3) is a conductive circuit, (4) is another circuit in the substrate, and (5) is a liquid crystal polymer film. The circuit board precursor 1 for the light-emitting body in FIG. 1 has a plurality of pairs of electrode predetermined portions 2 and 2 (that is, a light emitting element mounting portion). The electrode predetermined portions 2, 2 are connected to the other circuits 4, 4 in the substrate via the conductive circuits 3, 3, respectively. In addition, although the boundary between the electrode predetermined part 2 and the conductive circuit 3 is not necessarily clear, the site | part which should mount a light emitting element in the edge part of the conductive circuit 3 can be called an electrode predetermined part.

In Fig. 1, the dotted line is a cutting schedule line when the light emitters are used individually, and when the final product is produced by a method in which the light emitting elements are mounted, the broken line is cut at the necessary place based on the dotted line. In addition, (6) is a sprocket for substrate transfer (it mentions later in detail).

In addition, the circuit board precursor for the light-emitting body of FIG. 1 has a pair of electrode predetermined portions to be mounted on the light emitting element with respect to the recessed portion 1, and has a plurality of scheduled portions to be formed on the continuous circuit board. In the case where a plurality of light emitting element mounting portions are formed in this way, by forming recesses in each portion, a long light emitting circuit board and a light emitting body can be continuously manufactured, and these can be cut and used (Figs. 19 and 23). See).

The electrode predecessor may be a pair when there is one light emitting element mounted in the recess, for example, but when two or more light emitting elements are mounted in one recess (for example, all three primary colors of light can be emitted). In order to achieve this, in the case where three light emitting elements of red, blue, and green are mounted in one recess, the recess portion requires a predetermined number of electrode predetermined parts corresponding to the number of light emitting elements to be mounted (for example, two Two pairs of electrode predetermined portions when the light emitting element is mounted, and three pairs of electrode predetermined portions when the three light emitting elements are mounted).

For example, in a pair of electrode predetermined | prescribed parts, a light emitting element is arrange | positioned at one electrode predetermined part, and the other electrode predetermined part and a light emitting element are electrically connected by wire bonding etc. Therefore, when a plurality of light emitting elements are mounted in one recess, the electrode predetermined portion for directly arranging the light emitting elements is required depending on the number of light emitting elements to be mounted. In some cases, the light emitting element may be shared. Therefore, in this case, in one recess, the electrode predetermined portion connected to the light emitting element by wire bonding or the like may be smaller than the number of light emitting elements to be mounted on the recess. That is, the "one pair" electrode predetermined portion refers to a pair of electrode predetermined portions capable of mounting one light emitting element, and does not necessarily prescribe the number of electrode predetermined portions. For example, when two light emitting elements are mounted in one recess, four electrode predetermined portions may be formed. However, in many cases, one electrode predetermined portion can be shared by two light emitting elements, so that one recess portion is formed. Three electrode scheduled parts can be provided per predetermined site. Similarly, when three light emitting elements are mounted in one recess, four electrode predetermined sections can be provided per one recessed site.

It is preferable to design the circuit pattern so that the remaining area of the metal layer is as large as possible. The larger the remaining area of the metal layer, the higher the reinforcing effect of the substrate, and thus the higher the strength of the substrate. As will be described later, heat is emitted when the light emitting element emits light, and thus it is preferable to exclude this, but the larger the remaining area of the metal layer, the better the heat dissipation effect by the metal layer (circuit). It is also preferable to leave a metal layer in the sprocket portion used in the continuous production from the viewpoint of increasing the strength and enabling stable continuous production. Processing of parts other than such a circuit is very advantageous since it can be formed simultaneously with the circuit pattern by the etching method.

If the exposed portion of the liquid crystal polymer is small in the main portion of the circuit board for the light emitting body, that is, the remaining area of the metal layer is large, a light emitting body having high light reflectance and excellent luminance can be obtained. On the other hand, when the ratio of the circuit portion to the portion deformed in accordance with the formation of the recessed portion increases, there is a possibility that the possibility of circuit breakage increases. Therefore, in the circuit board precursor before forming the recessed portion, the proportion of the area occupied by the metal circuit pattern in the portion that should be the wall surface of the recessed portion is 20 to 90% (more preferably, 45% or more and 65% or less). It is preferable to form a circuit pattern so that This is because the luminance of the light emitting body can be partially compensated for by the high reflectance of the metal circuit surface while suppressing the occurrence of defective products.

Moreover, it is preferable that the electrically conductive circuit for connecting the electrode plan part and another circuit in a board | substrate has the elongation value which considered the deformation | transformation at the time of carrying out the deformation | transformation which accompanies elongation of a liquid crystal polymer film on a plane. Since the metal which can be used for the formation of the circuit pattern is very poor in the formability under the recessed condition, as compared with the liquid crystal polymer film, the circuit part located at the site where deformation is required to be elongated when the recess is formed (i.e., the conductive Breakage is likely to occur in a circuit). Even in the case where no breakage occurs, internal stress remains in the metal layer, which may lower the reliability of the product. Moreover, for example, when plating on copper foil and then three-dimensionally molding this, peeling of plating might occur. On the other hand, when the above-described shape is provided to the conductive circuit, the breakage of the circuit during the formation of the recessed portion can be highly suppressed, and a circuit board for a light emitting body having a recessed portion having more excellent reliability can be obtained. In particular, when the light emitting element or the light emitting body is enlarged and a larger recess is provided, or when a bending deformation with a smaller curvature is required, it is very effective to ensure the stability of the recess formation when the conductive circuit has the above shape. to be.

The reason why such an elongation value is "planar" is that the planar circuit pattern can be easily formed by an ordinary circuit pattern forming method such as etching subsequent to adhesion of the copper foil. In addition, it is not necessary to increase the process as in the case of forming such an elongation value with a lead wire or the like.

As a shape of the "extension value which considered the deformation | transformation at the time of the deformation | transformation with liquid crystal polymer film accompanying elongation" in the said conductive circuit, the shape curved in planar view is mentioned, for example. In the case where the conductive circuit has such a shape, when the liquid crystal polymer film undergoes deformation accompanied with elongation, the gap between the curves is opened, so that the apparent length increases, so that the breakage of the conductive circuit is highly suppressed. Therefore, if the conductive circuit of this shape is designed to be located at the site where the liquid crystal polymer film undergoes deformation along the elongation during formation of the recess (specifically, mainly the recess wall surface), the breakage of the circuit pattern is further increased during the formation of the recess. It is highly preventable.

The above-mentioned "curved shape" includes, for example, a so-called (wavy) bend shape, a wave shape, a zigzag shape, and the like (these shapes are all in plan view. The same applies hereinafter). More specifically, U-shaped; Sigmoid; V-shaped; A shape in which any one of a U shape, an S shape, and a V shape is continuous; A shape in which any one of a U-shape, an S-shape, a V-shape, and the like and an inverted shape thereof alternate alternately; Continuous shape containing these two or more shapes; Etc. can be mentioned. In addition, in the case of continuous shape, the magnitude | size and the degree of curvature of each shape (U shape, S shape, V shape, etc.) do not need to be constant. In the case of U-shaped or S-shaped, the bent portion may have an angle such as a right angle, and may be curved in a curve.

In addition, in the said "curved shape", two or more slits which do not reach the other end while facing from one end to the other end in a substantially orthogonal direction with respect to the direction toward the other circuit in the substrate from the electrode predetermined portion are the slits. The shape provided so that the start end of may be alternated is also included (hereinafter, simply referred to as "slit shape").

In the case of the slit shape, the number of slits provided in the conductive circuit, the distance between the slits, and the length of the individual slits are not particularly limited as long as the fracture preventing action of the conductive circuit can be sufficiently exhibited at the time of forming the recess. For example, the interval, position, length, angle, and the like may be appropriately selected depending on the shape of the recessed part to be molded, which can sufficiently alleviate the stress applied to the conductive circuit during molding.

The specific shape and size of the shape curved in the plane view (the above-mentioned wave shape, wave shape, zigzag shape, slit, etc.) are based on the current value flowing through the conductive circuit and the thickness of the metal layer. For example, the width of the conductive circuit (the length of the slit in the slit shape (the length left as the conductive circuit)) or the number of (wavy) bends (in the case of the slit shape) Can be determined through production verification by actual machine so that the conductive circuit can maintain the strength that can withstand the molding process further based on this calculated value. In the case of the slit shape, the length of the slit is usually about 50% or less when the width of the conductive circuit is narrow, and may be over 90% when the width thereof is wide.

In FIG. 2, an example of the board | substrate (plate shape) provided with the conductive circuit which has the said slit shape is shown, and FIG. 3 shows the board | substrate after providing recessed part in the board | substrate of FIG. 4 is a cross-sectional view taken along the line II of FIG. 2, and FIG. 5 is a cross-sectional view taken along the line II-II of FIG. 3. In Fig. 2 and Fig. 3, reference numeral 7 denotes a slit, in Fig. 3, reference numeral 8 denotes a recess bottom, and reference numeral 9 denotes a recess wall surface. In addition, in FIG.2-5, the duplicate description is abbreviate | omitted about the code | symbol same as FIG.1 (it is the same about each following figure).

In the flat substrate (Fig. 2), the slit 7 provided in the conductive circuits 3 and 3 is widened when the recess is formed (Fig. 3). Therefore, the apparent lengths of the conductive circuits 3 and 3 extend ((FIG. 3 is a plan view, so that the length of the conductive circuit does not appear to extend, but the slit spacing becomes wider, and in the depth direction of the figure). Elongating). Therefore, even if it is the electrically conductive circuit comprised from the metal which is inferior to a liquid crystal polymer film, the fracture is highly suppressed. The effect of preventing breakage of the conductive circuit due to the decrease in the degree of bending is similarly exhibited in other shapes (U-shape, etc.) exemplified above for the "curved shape". FIG. 6 shows an example of a substrate (flat plate) provided with the conductive circuits 3 and 3 having a S-shaped continuous shape among other shapes.

Moreover, as for "a shape curved by planar view," the thing of substantially radial symmetry is suitable. Here, "radial symmetry" refers to a shape in which a back pattern is equidistant from a center point in three-dimensional molding, and is repeated at a constant center angle, for example, center angle: 180 °, 120 ° or 90 °. Fig. 16 shows an example of the radially symmetric circuit pattern having a center angle of 180 °, Fig. 17 having a center angle of 90 °, and Fig. 18 having a center angle of 120 °. In the case of such a radially symmetrical shape, the force at the portion deformed during the formation of the recess is more uniformly applied to the circuit pattern as a whole. As a result, the force is not concentrated on only part of the circuit pattern, and the possibility of breakage can be reduced. One specific example of this form is shown in FIG. 17 and 18 respectively show radially symmetric circuit patterns in the case where four electrode portions are provided in one recess and three electrodes are provided. Here, the term &quot; substantially &quot; is a radially symmetrical shape that can disperse the force applied to the circuit pattern during the formation of the recessed portion, even if it is not a strictly radial symmetrical shape, for example, when one slit is present at one end. It means good.

The circuit pattern is formed on at least one side of the liquid crystal polymer film, but may be formed on both sides as necessary. When the circuit pattern is formed on both surfaces, each circuit can be used independently, or after forming a through hole, it can also connect and use both circuits by the well-known method of through-hole plating or embedding a conductive material.

<Formation of important part>

On the flat substrate precursor having a circuit pattern formed on the surface of the liquid crystal polymer film, a recess having a light emitting element mounting portion (electrode predetermined portion) and a bottom portion where a part of the conductive circuit should exist and a wall surface where a part of the conductive circuit should exist are formed. do. The method of forming the recessed portion is not particularly limited, and for example, a conventional molding method (press molding method, etc.) using a mold, a vacuum molding method, a pressure molding method, a vacuum pressure molding method, or the like can be adopted. Among them, the vacuum forming method, the press forming method, and the vacuum pressing forming method are advantageous in that the recesses can be formed on the circuit pattern forming surface without bringing the mold in close contact with each other, and therefore, damage to the circuit patterns and the like during the recesses can be prevented. On the other hand, in a conventional molding method such as a press molding method, there is an advantage that the molding position is more accurate. In the present invention, a suitable method can be adopted depending on the actual circuit pattern, the purpose of use thereof, and the like.

Although the number of recessed parts per board | substrate is not specifically limited, It is preferable to form in multiple numbers. This is because the circuit board can be cut at a desired position after the formation of a plurality, thereby enabling continuous manufacture.

There is no restriction | limiting in particular also in shape and size of a recessed part, What is necessary is just to make it the shape and size as needed. For example, the opening of the recess is made into a circle having a diameter of 0.5 mm to 30 mm, the diameter of the bottom of the recess is made into a circle of 0.45 mm to 27 mm, and the opening is made wider than the bottom, and the depth of the recess (the bottom from the opening) It is common to set it as the shape and size which made the vertical depth) to 0.1 mm-20 mm. However, the shape of the opening portion and the bottom portion is not limited to the circle, and can be appropriately selected.

As conditions for forming the recesses of such a shape and size, for example, when the liquid crystal polymer film is composed of an I-type liquid crystal polyester, in a general mold molding, the film temperature is set to 300 to 350 ° C and at 1 to 5 MPa. In the vacuum forming method, the film temperature is set to 300 to 350 ° C and the pressure is reduced to 0.1012 MPa or less, and the film temperature is 300 to 300 ° C under the vacuum pressing process. It is set as 350 degreeC, the pressure side is 0.29-0.59 MPa, and the pressure reduction side can be shape | molded for 0.1 to 15 minutes, and it cools to 200 degrees C or less, and takes out.

In the case of forming the recessed part, in order to prevent oxidation of the metal layer, it is preferable to mold in an atmosphere containing a reducing gas under an inert gas atmosphere. When the oxide film is formed on the surface of the metal layer by molding in the air, for example, the oxide film can be easily removed by immersing it in a nitric acid solution or the like of about 4 regulations and then washing with water sufficiently.

When the recess is formed by the temperature condition or the pressure condition, the elastic modulus is used to reorient the molecular chain of the liquid crystal polymer in the stretch direction at the site of deformation (particularly and in the vicinity of the wall surface of the recess) which is accompanied by elongation. This becomes high, and the shape retention property of a recessed part, ie, the physical property of the shape retention phase as a casting case of low viscosity resin (sealing resin before hardening) improves. Therefore, in order to secure an equivalent recessed shape retaining agent to a circuit board which is not improved in elastic modulus due to the reorientation of the molecular chain of the liquid crystal polymer film, a thinner liquid crystal polymer film can be applied, resulting in a higher weight of the circuit board. Low cost and thinning can be achieved.

For example, in a type I thermotropic liquid crystal polyester film having a thickness of 100 μm, the tensile modulus of elasticity is about 6300 N / mm 2 in the case where the linear expansion coefficients in the MD direction and the TD direction are adjusted to about 16 ppm / ° C. When re-stretching twice in one direction, the tensile modulus in the stretching direction is about 1.5 times. This phenomenon is remarkable in the liquid crystal polymer film which can easily perform orientation control of molecules by stretching.

In the substrate of the present invention, even when the recess is formed, deformation along with elongation occurs at a boundary between a portion of the recess wall surface and its vicinity, particularly the bent portion of the recess opening, and the recess 1 bottom wall surface, thereby improving the elastic modulus. The phenomenon is remarkable. Therefore, in the exposed part of the liquid crystal polymer film, the overall flexibility is abundant. In particular, the shape retention of the recessed part is improved in that it is hardened by the increase of the elastic modulus in a part of the recess wall and its vicinity.

<Structure of Board>

In the board | substrate of this invention, in addition to the form of only one light emitting element mounting part (namely, only one pair of electrode parts), as shown in FIG. 1, the form in which two light emitting element mounting parts exist is also preferable. The substrate shown in Fig. 1 has a transfer sprocket 6, which is a so-called TAB substrate, which allows continuous operation such as recessed portion formation, mounting of a light emitting element, sealing with a sealing resin, and the like.

In consideration of the case of performing a continuous operation with a TAB substrate, it is preferable that the circuit board of the present invention is elongated (for example, in the form of a tape). For example, it is recommended that the length is 0.5 m or more, more preferably 50 m or more. In the case of such a long circuit board, it is preferable to wind it on a roll from a viewpoint of good handleability. However, of course, it can also be manufactured in a patch form.

In addition, in the board | substrate shown in FIG. 1, after mounting a light emitting element, sealing it with the sealing resin, it cut | disconnects in the cutting | disconnection plan line (dotted line part in FIG. 1), and acquires several light-emitting body (LED) which has one light emitting element. In addition to the use, only the upper and lower sprockets 6 and 6 in FIG. 1 are cut at a cutting schedule line, and can also be used as a tape-shaped light emitting body in which a plurality of light emitting elements are mounted. In the circuit board of FIG. 1, the circuit is continuous over the entire length of the substrate shown in the drawing. For example, in a long circuit board, the circuit does not need to be continuous over the length of the longitudinal direction. For example, in order to obtain a plurality of circuits of a specific length, a circuit pattern of a specific shape is repeatedly formed for each specific length (for example, 1m), and the repeating units of the pattern are disconnected or different patterns for each specific length. Circuits can be provided, and the different patterns can be disconnected. An example of the pattern of attaching a socket to the latter is shown in FIG. 19. 20 is an enlarged view of one pattern in FIG. 19. As shown in Fig. 23, a circuit of a pattern of a pattern applicable to a display device (dot matrix) is manufactured, and then cut and used at a desired position.

In the tape-shaped light emitter obtained from the substrate of FIG. 1, the tape-shaped light emitter is a parallel circuit, and is connected to an external circuit including a power supply at both ends of the light emitter (in FIGS. Light emission can be confirmed with high efficiency for all light emitting devices. Therefore, by connecting the external circuit, the light emission confirmation inspection of the light emitting element in the manufacturing step becomes easy. Moreover, it can also be used as a manufacturing means of a surface light-emitting body.

In the conventional planar light-emitting body, it is necessary to erect a plurality of light-emitting bodies having one light-emitting element on a panel substrate, and to wire and solder each light-emitting body, and the production thereof is very complicated. However, in the case of the tape-shaped light emitters obtained from the substrate of FIG. 1, a plurality of tape-shaped light emitters may be placed in parallel, and the ends of each tape-shaped light emitter may be connected to an external circuit including a power supply unit, and wiring and soldering for each light emitting element are unnecessary. By covering the surface with a translucent plate or the like, the planar light-emitting body can be produced simply, and the thickness, miniaturization, and weight of the planar light-emitting body can also be achieved. Of course, it is also possible to set it as a linear light emitter and a multipoint light emitter. In addition, the circuit can be easily designed freely, such as series, parallel, and a combination thereof.

Moreover, in the board | substrate of this invention, since circuit pattern formation with high degree of freedom and recessed part formation are compatible, it can be used also as a board | substrate of a planar light-emitting body. 7 is an example of a precursor of a circuit board for an area light-emitting body. Since the plurality of light emitting elements (24 in FIG. 7) can be directly mounted on the substrate of FIG. 7, the manufacturing process can be greatly simplified as compared with the conventional planar light emitting body. In the substrate of FIG. 7, each of the light emitting element mounting portions has a separate circuit, so that individual light emitting elements can be connected to individual external circuits. Therefore, since light emission and / or extinction can be adjusted for each light emitting element, it can be used not only as a flat surface light-emitting body but also as a display device (dot matrix). In addition, by using the substrate of the present invention, the continuous production of such a display device is also facilitated, and the display device can be thinned, miniaturized, lightweight, and resource-saved, and a flexible display device can be obtained.

That is, in the conventional display device (dot matrix), for example, a plurality of unit blocks each having one to a plurality of light emitting elements are combined individually, the whole is supported in a case, and wiring from each block is connected. . In the unit block, a plate-shaped circuit board on which a light emitting element is mounted is placed in a molded case of a thermoplastic resin having a depth of about 10 mm, and mold-sealed with a transparent resin such as an epoxy resin to insulate the environment. In addition, an umbrella shaped body is coated on the light emitting element in the molded case in order to conceal the circuit board and increase the take-out efficiency of light. At the bottom of the molded case of the unit block, a hole for taking out light generated from the light emitting element is provided. Therefore, when molding transparent resin at the bottom of the molded case of the unit block, in order to prevent the leakage from the hole, the film which has adhesiveness is attached, and after the sealing by transparent resin, the adhesive film is peeled off.

In such a conventional display device, since the unit block requires a large amount of transparent resin, the weight is large and heat dissipation is also bad. In addition to these transparent resins, it is necessary to use a large number of materials such as molded cases and other subsidiary materials (cases for holding an umbrella-shaped molded body or a unit block). In addition, when the circuit board is set in a molded case and sealed with a transparent resin, the transparent resin is flowed in the presence of a complicated three-dimensional structure such as a light emitting element or the molded body of the umbrella shape, and thus bubbles are contained in the transparent resin. There is a problem that it is easy to remain and workability is bad. Moreover, after sealing with transparent resin, there is a labor which should peel the said adhesive film, and also it is disadvantageous also in that the peeled adhesive film becomes waste.

On the other hand, in the substrate of the present invention, a display device having a plurality of light emitting elements can be formed by only sealing the light emitting element portion, so that the amount of use thereof can be reduced to less than one tenth of conventional ones. In addition, since it is not necessary to use a molded case separately, a significant weight reduction and a raw material cost can be achieved. Moreover, it is not necessary to use the said adhesive film, and workability | operativity is also favorable. Moreover, also at the time of disposal, it is an environmental measure in that the quantity (especially resin amount) can be reduced significantly.

At present, a large-sized display using LEDs has been put into practical use for outdoor use in wall surfaces of buildings and the like. Here, a large number of shell-type LEDs with high brightness are integrated. On the other hand, indoors, liquid crystal monitors and plasma displays have been put to practical use as thin, large-sized displays. However, the technical difficulty is increased in order to further increase the size of the displays, resulting in a high cost which is proportional to the size.

In the board | substrate of this invention, as shown in FIG.7 or FIG.23, the structure which can emit | emit and turn off each light emitting element can also be employ | adopted in a tape-shaped or planar light-emitting body. Therefore, by mounting a large number of dots formed by disposing three kinds of red, green, and blue light emitting elements at high density, it is possible to easily provide a very lightweight, thin and large display. This display is suitable for a field where low luminance is applied, for example, indoors, compared to a display composed of shell-type LEDs.

21 is an example of an application circuit having the radial symmetric circuit pattern of FIG. 16, and is an example of a circuit board precursor for a display device (dot matrix) light-emitting body. Fig. 22 is a view showing the appearance of an ect matrix product prepared from the precursor. The wiring part and the socket part which are shown below are flexible, and in actual use, it turns and uses them, as shown in FIG. 23 is an example which shows the pattern at the time of continuously manufacturing on a tape as a unit the circuit board precursor for light emitters shown in FIG.

As described later, after the light emitting device is mounted on the substrate, the light emitting device is sealed with a sealing resin so as to cover the light emitting device. However, the liquid crystal polymer of the substrate before or after the recess is formed from the viewpoint of increasing the adhesion with the sealing resin. It is also preferable to surface-treat a film exposed part. As such surface treatment, an ultraviolet irradiation treatment, a plasma irradiation treatment, a sand blast treatment, an alkali treatment, etc. are mentioned, for example. It is also possible to apply a combination of two or more of these treatments. In the liquid crystal polymer circuit board obtained by thermocompression bonding of the roughened metal, excellent adhesion can be obtained only by the surface of the liquid crystal polymer after the metal is removed.

<Configuration of Light Emitting Body>

The light-emitting body of the present invention has the circuit board for light-emitting body of the present invention after formation of recesses, and there is no particular limitation on other configurations, and various configurations used in conventionally known light-emitting bodies can be adopted.

8, sectional drawing which is an example of the light-emitting body of this invention is shown. The light emitting element 10 is mounted so as to be electrically connected to either one of the pair of electrode portions 2 and 2 of the circuit board 1 for the light emitting body, and the other electrode portion 2 and the light emission. The element 10 is electrically connected by the wire bonding 11. After that, the recess 13 is covered with a sealing resin 12, and the resin is cured to seal the light emitting body 13.

Although the light emitting element 10 is provided with many kinds, including GaAlAs system, for example, there is no restriction | limiting in particular in the light emitting body of this invention, The kind of light emitting element which can ensure the required light emission color can be employ | adopted. As the mounting of the light emitting element 10, for example, a die bonding using a known silver paste or the like can be applied.

There is no restriction | limiting in particular also about the wire bonding 11, The thing (normally gold) of the material normally used in the light emitting field field can be used.

The sealing resin 12 is not particularly limited as long as the sealing resin 12 has transparency enough to allow the light emitted from the light emitting element 10 to pass well, and conventionally known ones (epoxy resin and the like) can be used.

Moreover, in the case of the light emitting body obtained from the board | substrate of FIG. 1, since it is a tape form, it can also wind up on a roll and ships.

In the light-emitting body of the present invention, it is also preferable to have heat dissipation means on the opposite side of the circuit pattern formation surface of the substrate. 9 shows an example of a light emitting body having heat dissipation means. The light emitter 13 in FIG. 9 has a heat sink 14 as a heat radiation means.

In the light-emitting body, measures to exclude heat generated during light emission are desired, but conventionally, the lead frame is enlarged and arranged through this. However, when the size of a light-emitting body becomes large, there exists a problem that array efficiency falls.

In the light emitting body of the present invention, it is possible to ensure good heat deformation resistance (preventing thermal deformation of the substrate during soldering) while reducing the thickness of the liquid crystal polymer film used for the substrate, which is different from that of the conventional injection molding resin substrate. As compared with the coating film made of paint, highly reliable insulation can also be maintained. Therefore, by providing heat dissipation means such as a heat sink made of a material having excellent thermal conductivity on the surface of the liquid crystal polymer film (opposite side of the circuit pattern formation surface), the arrangement from a large area of the substrate, unlike the arrangement by a conventional lead frame This makes it possible to achieve an efficient arrangement without worrying about the occurrence of a short circuit.

Examples of the heat sink include metal plates such as aluminum plates and magnesium plates, resin plates containing a large amount of inorganic materials excellent in thermal conductivity, and glass plates. The heat sink may be attached to the heat sink in accordance with the shape of the substrate, and the substrate may be inserted into the heat sink. However, it is more preferable to bond the substrate and the heat sink to each other, or to bond the substrate with a method using an adhesive.

Further, as shown in Fig. 9, as the heat dissipation means, it is more preferable to use the heat dissipation plate 14 having the refrigerant passage holes 15. In this case, a more efficient arrangement is possible. As the coolant, water and other known coolants can be applied.

In addition, although the above description summarizes the result which examined all about the light emitting body, it is clear that this invention can be applied also for liquid sealing type semiconductors other than a light emitting body.

Example

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail based on an Example. However, the following Examples do not limit the present invention, and all modifications are made within the technical scope of the present invention without departing from the spirit and scope of the invention. % "Is a mass reference | standard unless there is particular notice.

Moreover, the linear expansion coefficient of the film mentioned later was made into the test piece width | variety: 4.5 mm, the intervertebral distance: 15 mm, and a load: 1 g with respect to MD direction and TD direction of a film by TMA method, and heated up to 200 degreeC from room temperature. The temperature calculated | required from the dimensional change of the test piece measured between 160 degreeC and 25 degreeC at the time of cooling (heating rate: 5 degree-C / min) and temperature-fall rate: 5 degree-C / min is then averaged.

Experiment 1 <Production of Light Emitting Circuit Board and Light Emitting Body>

Example 1

Type I thermotropic liquid crystal polyester film (heat-resistant thermoplastic resin film, `` BIAC BA '' manufactured by Japan Pangoretex Co., Ltd., liquid crystal transition temperature: 335 ° C, thickness: 100 µm, linear expansion coefficient: 16 ppm / ° C in both MD and TD directions). Cu alloy foil on one side ("NK120" manufactured by Nikko Material Co., Ltd., Cu alloy single-sided roughened product for high-conductivity lead frame containing 0.2% Cr-0.1% Zr-0.2% Zn, thickness: 18 µm, coefficient of linear expansion 17.4 ppm / ° C.) was attached under the conditions of temperature: 340 ° C., pressure: 3.9 MPa, and time: 5 minutes, a sprocket as shown in FIG. 10 was installed, and a resin film having a metal layer was obtained.

Next, the circuit pattern of the structure shown in FIG. 10 and FIG. 11 was provided in the said resin film using the etching method. In FIG.10 and FIG.11, the numerical value except a code | symbol means length, and a unit is mm. In FIG. 10, 16 is a guide hole of 5 mmphi, and the diameter of the sprocket 6 is 1.3 mm. The guide hole is a hole for mold molding, and the sprocket is for the purpose of tape feeding in continuous use.

Using a roll laminator (roll surface temperature: 105 ° C) heated with a basic aqueous solution developing type dry film resist ("HF450" manufactured by Hitachi Kasei Co., Ltd.) having a thickness of 50 µm on the surface of the metal layer, the speed was 0.5 m / min and the linear pressure. : Laminated on the conditions of 0.2-0.4 MPa, and it was left to stand at room temperature for 15 minutes. Subsequently, the predetermined mask was superimposed on the resist coating surface, and the ultraviolet-ray was irradiated on the conditions of 100 mJ / cm <2> using the vacuum adhesion exposure machine. Furthermore, it was left to stand at room temperature for 15 minutes, and after that, using a 1% aqueous solution of Na ₂ CO ₃ , dry film resist was developed under the conditions of temperature: 30 ° C., spray pressure: 0.2 MPa, and time: 60 seconds. Formed.

The metal layer of the resin film after resist pattern formation was etched using ferric chloride aqueous solution (500 g of ferric chloride dissolved in 1 L of 3% aqueous solution of HCl). Thereafter, the dry film resist was stripped off using a 3% aqueous solution of NaOH at a temperature of 50 ° C. and a spray pressure of 0.1 MPa to obtain a flat light-emitting circuit board precursor.

The above-mentioned light emitting circuit board precursor was formed with recesses by a die molding method. The shape of the recessed portion is circular at the bottom of 1.7 mm in diameter and circular at the opening of 2.3 mm in diameter, and has a vertical depth of 0.85 mm from the recessed opening to the bottom. 12 is a cross-sectional view of the recessed part (II-II cross-sectional view after forming the recessed part in the substrate of FIG. 11). In FIG. 12, the unit of the numerical value (curvature radius) which added the code | symbol and "R" is mm. Molding conditions were the heating temperature: 320 ℃, pressure: 0.5 MPa, time: 5 minutes and was molded in a nitrogen stream.

The surface of the light emitting circuit board after the recess was formed by irradiating ultraviolet light for 30 seconds under conditions of 32 mW / cm 2 using low pressure mercury or the like. The light emitting element was mounted on the bottom surface of the recessed part of the light emitting circuit board after the surface treatment. As a light emitting element, "GaN-based blue LED chip part No .: E1C40-OB001-02" by Toyota Synthetics Co., Ltd. was used, and this was die-bonded to one side of an electrode part (electrode predetermined part) with silver paste. The light emitting element and the other electrode portion were wire bonded by gold wire. Thereafter, a two-component epoxy resin-based transparent sealing agent ("HL2000A, HL2000B2" manufactured by Inabata Industries Co., Ltd.) was filled in the main portion of the circuit board on which the light emitting device was mounted, covering the light emitting device, and the sealing material was kept at 125 ° C for 1.5 hours. The mixture was further cured, secondary cured at 150 ° C. for 6 hours, insulated from the environment, and a long tape-like light emitting body was obtained.

In addition, the tape-shaped light emitter is cut to produce five tape-shaped light emitters having ten light emitting elements, and are adhered in parallel to five rows of phenolic resin substrates. The external circuit incorporated therein was connected by soldering at 260 ° C using lead-free soldering ("M705" manufactured by Senju Metal Co., Ltd.). Next, the translucent acrylic plate was arrange | positioned at the surface, and the surface light-emitting body was obtained. Formability and the formation efficiency of the surface light-emitting body were good. It was confirmed that electricity was supplied to the obtained surface light-emitting body, and light emission such as light through the paper was possible.

Example 2

As the liquid crystal polymer film, a type II thermotropic liquid crystal polyester film (liquid crystal transition temperature: 280 ° C, thickness: 100 m, linear expansion coefficient: 16 ppm / ° C in both the MD direction and the TD direction) was used.

The production method of the type II thermotropic liquid crystal polyester film is as follows. Type II thermotropic liquid crystalline polyester ("Betutora A950" manufactured by Polyplastics Co., Ltd.) is melted in a single screw extruder (screw diameter: 50 mm), and the T die (lip length: 300 mm, lip clearance: 2.5) at the tip of the extruder. Mm, die temperature: 300 ° C.), and a liquid crystal polyester film having a thickness of 500 μm was obtained by extruding and cooling on a sheet under a draft ratio of 5 conditions. Using a laminator having a pair of thermal rolls, a porous polytetrafluoroethylene (PTFE) film (thickness: 40 µm, average pore size: 0.5 µm, hollow ratio: 80%) was formed on both surfaces of the liquid crystal polyester film. It was thermocompression-bonded on the conditions of 320 degreeC and a roll circumferential speed: 2 m / min, and after passing through a pair of cooling rolls (temperature: 100 degreeC), it was made into a laminated body. This laminated body was extended | stretched with the biaxial stretching machine. As for extending | stretching conditions, temperature was 300 degreeC, magnification was 1.6 times in MD direction, 3.2 times in TD direction, and the stretching speed was 20% / sec. Thereafter, the porous PTFE films on both sides were peeled off to obtain a type II thermotropic liquid crystal polyester film having a thickness of 100 μm.

The metal foil as used in Example 1 was attached to one side of the obtained liquid crystal polymer film under the conditions of temperature: 275 ° C, pressure: 3.9 MPa, time: 5 minutes, and a sprocket as shown in FIG. The resin film which has a metal layer was obtained. The resin film which has this metal layer was etched by the method similar to Example 1, and the board | substrate precursor for flat light-emitting bodies was obtained.

Further, for the above flat light emitting circuit board precursor, the light emitting circuit board and the long tape having the flat light emitting circuit board main part in the same manner as in Example 1 except that the molding temperature at the time of forming the recessed part was 265 ° C. A phase light-emitting body was produced. An attempt was made to produce a planar light-emitting body from the tape-shaped light-emitting body in the same manner as in Example 1, whereby the soldering temperature could not be tolerated and a defect occurred. Therefore, the surface light-emitting body was produced in the same manner as in Example 1 except that soldering was carried out at a temperature of 220 ° C. using ordinary soldering (“Sn63” manufactured by Senju Metal Co., Ltd.) containing lead. It was equivalent formability and formation efficiency. Moreover, when this surface light-emitting body was energized, it was confirmed that light emission equivalent to Example 1 is possible.

Comparative Example 1

Example 1 except having used the copper foil adhesion | attachment thermosetting polyimide film ("Espanex" made by Sinitetsu Chemical Co., Ltd., thickness: 50 micrometers, copper foil thickness: 12 micrometers) instead of the liquid crystal polymer film with Cu alloy foil. In the same manner as described above, a flat circuit board precursor for a light-emitting body was manufactured. Attempts were made to form recesses in the same manner as in Example 1, but this was impossible.

Comparative Example 2

An elongated tape-like light-emitting body was fabricated in the same manner as in Example 1 except that the recessed portion was not formed using the flat-shaped light-emitting circuit board precursor prepared in Comparative Example 1, but before the thermosetting of the sealing agent, The sealing was impossible because the sealing agent flowed out.

Comparative Example 3

A flat substrate light-emitting circuit board precursor was produced in the same manner as in Example 1 except that a polyetherimide film (manufactured by Mitsubishi Resin, thickness: 100 μm) was used instead of the liquid crystal polymer film. In the same manner as in Example 1, attempts were made to form recesses, but large deformations occurred and could not be processed. The linear expansion coefficient in the film plane direction of the polyetherimide film is 56 ppm / 占 폚, which is considered to be because the difference with the linear expansion coefficient of Cu alloy foil was large.

Comparative Example 4

A circuit board precursor for a plate-shaped light-emitting body was produced in the same manner as in Comparative Example 3 except that the aluminum plate having a thickness of 1 mm was bonded to the opposite side of the circuit pattern formation surface of the polyetherimide film used in Comparative Example 3. The recess was formed in the same manner as in Example 1, but the shape of the recess was not as sharp as in the conventional injection molded article due to the presence of the aluminum plate, resulting in poor moldability. Therefore, subsequent evaluation was stopped.

Experiment 2 <Production of Light-Emitting Body with Radiation Means>

Example 3

When the surface light-emitting body obtained in Example 1 was emitted under an environment of 25 ° C, after 10 minutes, the temperature of the surface of the light-emitting body (light emitting surface) was 28.5 ° C.

Example 4

A heat sink (a die-cast molded plate made of aluminum) having a refrigerant passage hole as shown in Fig. 9 was formed on the opposite side of the circuit pattern formation surface of the planar light-emitting body obtained in Example 1 using an adhesive. Thereafter, the planar light-emitting body was allowed to emit light under a 25-degree C environment while allowing 20 ° C cooling water to pass through the coolant passage hole, and the temperature of the light-emitting surface (light-emitting surface) after 10 minutes was 25.5 ° C.

Thus, in the light emitting body of the present invention, by providing the heat dissipation means, heat generated during light emission can be well excluded.

Experiment 3 <Production of Light Emitting Circuit Board and Light Emitting Body with Conductive Circuits of Specific Shape>

Example 5

In the etching pattern shown in FIG. 13, the flat part of the patterned part forming part shown by FIG. 14 (henceforth "with a slit"), or the pattern (henceforth "no slot") shown in FIG. The circuit board of the upper phase was produced in the same manner as in Example 1, recessed portions were formed by the die molding method, and the disconnection state of the conductive circuit was confirmed. In addition, the dotted line (circle) in FIG.14 and FIG.15 has shown the recessed part formation plan part (henceforth "a recessed part formation plan line"), and the inside circle | round | yen is a boundary part of a recess bottom face and a wall surface, and the outside circle It is the boundary between the recessed wall and the outside of the recess. The dashed-dotted line in FIG. 14 and FIG. 15 has passed the center point of the recessed part formation plan part. Numerical values (0.47 mm, 0.85 mm, 1.0 mm and 1.15 mm) indicating the slit positions in FIG. 14 are angles in the concentric circle centered on the center point of the recessed portion forming portion from the one-dot chain line and the line segment passing through the conductive circuit end portion. The distance to the intersection with the midpoint of the upper and lower ends of the slit opening side is shown.

For the circuit board with a slit, the pattern is supplemented. Four slits are provided for each conductive circuit, and the starting end of the slit is alternated. The width of the metal layer remaining portion of the conductive circuit in the slit forming region was 0.05 mm and the width of the slit was 0.1 mm. The slot direction was aligned with the direction of the recessed formation line so that the slit portion was positioned at the most curved portion of the substrate at the time of recessed formation, and the width of the slit opening was slightly widened (0.1 mm).

The recessed shape was the same as in Example 1. Molding conditions were: temperature: 330 ° C, pressure: 1.3 MPa, time: 5 minutes, extraction temperature: 200 ° C, and the number of presses until the shape of the final recess was obtained was once (one press) In the case where the recess is completely formed, hereinafter referred to as "one-step press" and five times (when the press for forming the recess is performed in five steps and the recess is gradually formed, the `` five-step press '' In both cases, disconnection of the conductive circuit was visually confirmed. The number of tests was set to 20, the case where the disconnection generate | occur | produced in the electrically conductive circuit by the shaping | molding of recessed part was made into defect, and the generation rate was shown as the percentage. The results are shown in Table 1.

Defective rate at recessed part (%) 1st stage press 5-step press With slit 0 0 No slit 100 0

As can be seen from Table 1, even in a circuit board without a slit, by forming a process by increasing the number of steps by the multi-stage pressing method (five-stage pressing in this experiment), recessed portions were possible. On the other hand, in a circuit board in which a slit is provided in the conductive circuit, it is possible to form recesses without disconnection of the conductive circuits by using fewer steps (one-step press in this experiment), so that the recess formability is better.

Experiment 4 <Checking the Effect of Reflectance Improvement>

Example 6

On the condition of temperature: 310 degreeC, pressure: 3 MPa, time: 5 minutes using what was single-sided roughening process by the 18 micrometer-thick electrolytic copper foil (made by Koga Circuit Foil company, "GTS-18"), It adhere | attached on the 100 micrometer-thick liquid crystal polymer film (manufactured by Japan Corporation, "BIAC-BC"), and obtained the resin film which has a metal layer. The resin film which has this metal layer was etched on the conditions similar to Example 1, and in the circuit pattern shown in FIG. 10, the recessed part formation plan part has a flat board | substrate precursor for light-emitting bodies which has the shape of FIG.

A silver layer having a thickness of 3 m was formed on the copper foil by electroplating on the surface of the obtained light-emitting circuit board precursor. In the case where the conical trapezoidal recesses having a diameter of 2.3 mm, a bottom diameter of 1.7 mm, and a depth of 0.85 mm are three-dimensionally formed in a portion including the electrode portion (electrode predetermined portion) using a mold, the recess portion The area of the circuit part (metal part) occupying the part which becomes the wall surface of was calculated. Similarly, also in the circuit pattern (FIGS. 14 and 15) formed in Example 5, the area of the circuit part which occupies to the part used as a recessed part wall surface was calculated. In the circuit board precursor, when the area of the portion serving as the recessed wall surface is D, the area of the circuit portion occupying the portion serving as the recessed wall surface in FIGS. 14, 15, and 16 is A, B, and C, respectively. Is as follows.

A: B: C: D = 13.4: 18.9: 54.1: 100

Therefore, it can be seen that the proportion of the circuit pattern shown in FIG. 16 to the wall surface of the recessed portion in which the light emitting element is to be mounted is greatly increased.

Separately, the light reflectance on the liquid crystal polymer film surface and the silver electroplating surface was measured using a spectrophotometer (Hitachi Seisakusho Co., Ltd., "U-3500") using the above-mentioned light emitting circuit board precursor. A result is shown in Table 2 as an increase rate of the reflectance in the silver plating surface with respect to the liquid crystal polymer film surface.

wavelength % Increase Global (400-800 nm) 116 Red (630 nm) 107 Rust (560nm) 114.6 Blue (430 nm) 153.2

As a result, it can be seen that the reflectance on the silver plated surface is 1.53 times in the blue wavelength light and 1.16 times in the total visible light with respect to the liquid crystal polymer film surface. Therefore, as in the circuit pattern shown in Fig. 16, by increasing the proportion of the circuit portion occupying the wall surface of the recessed portion in which the light emitting element is mounted, the effect of compensating for the decrease in the reflectance of the short wavelength side light on the film surface can be expected, and thus a good light emitting body It was found that it can be obtained.

Experiment 5 <Checking the Effect of a Circuit Pattern with a Radial Symmetric Elongation Value>

Example 7

The circuit pattern shown in FIG. 16 was formed on the liquid crystal polymer film on the conditions similar to Example 6 except having used the rolled copper foil ("BHY-13B-T" by Nikko Material Company) instead of the electrolytic copper foil, A circuit board precursor was obtained. Similarly, a circuit board precursor for a light-emitting body of the circuit pattern shown in FIG. 14 was also created.

The recesses shown in the sixth embodiment are actually formed on these light-emitting circuit board precursors, and the micrographs of the electrode portions present at the bottoms of the recesses are photographed. In the circuit pattern of FIG. The distance (clearance) between two electrode parts was measured. In the circuit pattern of FIG. 16, the distance between two electrode parts (the diagonal part in FIG. 16) and the distance (the arrow part in FIG. 16) at the electrode inlet part between the two conductive circuits connected to the electrode part are measured. It was. The results are shown in Table 3. Here, "electrode entrance part" means the vicinity of the bottom face side in the boundary between the wall surface and the bottom face of a recessed part, and the distance between the "electrode terminal parts" means the distance between two electrodes.

Circuit pattern Lumbar formation 14 Electrode inlet 0.10nm Electrode end 0.11 nm Figure 16
Electrode end 0.10nm The other end of the electrode 0.10nm

As a result, even in the circuit pattern shown in Fig. 14, there is almost no problem in the electrode spacing due to the formation of the recesses, but in the circuit pattern shown in Fig. 16, i.e., the circuit pattern having the elongation value curved radially symmetrically in plan view, No change in electrode spacing due to formation was observed. This is considered to be because the force applied during the formation of the recess is uniformly dispersed in the circuit portion (metal portion) present in the wall planar portion of the recess and is not applied to only part of the recess.

Therefore, according to the circuit pattern which has the elongation value of radial symmetry, the defect resulting from the shift at the time of actually mounting a light emitting element can be prevented more effectively. In addition, the light emitting body having the circuit pattern has no change in the arrangement of the circuit portion (metal portion) in the recessed portion that reflects light generated from the light emitting element. That is, in the recess, a radially uniform pattern is formed from the center point. Therefore, the circuit pattern is excellent in uniformity of reflected light.

Experiment 6 <Confirmation of Adhesive Force>

Example 8

When the surface roughened metal foil was thermocompression-bonded on the liquid crystal polymer film and then etched, the adhesive force between the epoxy resin as the sealing resin and the film was examined. The used material is as follows.

Liquid crystal polymer film 1: "BIAC-BA" made by Japan Pangotex

Liquid crystal polymer film 2: Japan-Ago Gore-Tex company "BIAC-BC"

Copper foil: 18 µm thick electrolytic copper foil treated with one-sided roughening ("GTS-18" manufactured by Koga Circuit Foil Co., Ltd.)

Etching conditions were the same as in Example 1. However, the roughening process side of copper foil was stuck to the liquid crystal polymer film. Moreover, the roughness of the copper foil surface of the roughening side was Rz: 8 micrometers. The adhesive force was measured based on the adhesive force measuring method of JISK6850. That is, the obtained light-emitting circuit board precursor was affixed on the aluminum plate of width: 15 mm and thickness: 2 mm by the two-component epoxy resin transparent sealing agent ("HL2000A, HL2000B2" by Inabata Industries Co., Ltd.). The test sample is fixed symmetrically with a gripper of the tensile force tester at a position about 50 mm away from the adhesive surface, the tester is operated at a constant speed at which the adhesive part breaks at 65 seconds ± 20 seconds, and the force at the time of breaking Measured. The measurement was carried out 5 pieces for each test sample, and the average value was calculated | required. However, the adhesive surface was 15 x 15 mm. As a comparative example, in order to measure the adhesive force of copper foil (circuit surface) and a sealing agent, the same test was done in the state which does not etch. The results are shown in Table 4.

Test Sample Adhesive force (N / mm2) Untreated film1
Etched Film1 6.72
16.84 Untreated film2
Etched Film2 5.84
20.54 Copper foil (circuit surface) 14.42

As a result, the adhesion of the surface of the etched liquid crystal polymer film and the sealing agent after the surface-coated copper foil was adhered was proved to be significantly improved compared to the adhesion between the untreated film surface and the sealing agent. . Specifically, it is about 2.5 times in the said film 1 and about 3.5 times in the film 2, and this is higher than the adhesive force of copper foil (circuit surface) and a sealing agent. It is already known that the moisture resistance of the liquid crystal polymer itself is superior to polyimide, which has been used as a material for many flexible circuit boards. Therefore, by using the liquid crystal polymer film subjected to the etching treatment, the adhesion between the circuit board and the epoxy resin can be increased, whereby it is expected that a highly reliable product can be obtained.

Experiment 7 <Checking the Effect of a Circuit with Elongation Values>

Example 9

In the light-emitting circuit board precursor, the difference between the disconnection incidence rates in the case where the conductive circuit portion of the circuit pattern had an elongation value in consideration of the deformation at the time of formation of the recessed portion and did not have was examined. The material used is as follows.

-Liquid crystal polymer film: "BIAC-BA" made by Japan Pangotex

Copper foil: 18-micrometer-thick rolled copper foil treated with one-sided roughening (manufactured by Nikko Material Corporation, `` BHY-13B-T '')

The circuit patterns to be formed are shown in Figs. 14 to 16, and the etching conditions were the same as those in the eighth embodiment. Each pattern is set to Examples 9-1 to 3, respectively. After forming the recessed part by limiting the number of presses to one time on each obtained light-emitting circuit board precursor under the conditions of the said Example 1, the presence or absence of the disconnection was confirmed by microscope observation and the conduction test. Even when conducting, it was determined that the damage was observed in the circuit by microscopic observation as disconnection. Moreover, although the curvature radius in a recessed part boundary was 0.2 mm (refer FIG. 12), the recessed part in the more gentle curvature radius of 0.35 mm and 0.5 mm was also formed. Table 5 shows the results of disconnection incidence tested for 20 samples for each sample.

Curvature (mm) 0.2 0.35 0.5 Example 9-1 0 0 0 Example 9-2 100 0 0 Example 9-3 0 0 0

As shown in the result, when the curvature radius was increased to form a smooth recess, disconnection did not occur even by pressing in one step, but when the curvature radius was reduced, disconnection occurred in Examples 9-2. Therefore, when making curvature small, it is preferable to press at multiple stages. However, even when the radius of curvature was small, disconnection did not occur in the case of the circuit pattern having the elongation value according to the present invention.

Claims (26)

As a method of manufacturing a circuit board for a light emitting body, A step of forming a metal circuit pattern having at least one pair of electrode predetermined portions of the light emitting element on the surface of the liquid crystal polymer film, and each of the electrode predetermined portions connected to another circuit in the substrate via a conductive circuit (hereinafter, "a circuit pattern forming process. ", And The process of forming the recessed part which has the electrode predetermined part and the bottom part which the said conductive circuit should exist, and the wall surface which the said conductive circuit should exist in the site | part containing this electrode predetermined part (henceforth a "main part formation process"). Method for producing comprising a. The method of claim 1, A manufacturing method of forming a plurality of the recess. The method according to claim 1 or 2, And forming the electrode predetermined part so that a plurality of pairs of the electrode predetermined parts exist per one recessed part. The method of claim 1, The said liquid crystal polymer film is a manufacturing method using the thing in which the linear expansion coefficient of the direction parallel to a film plane is adjusted to 25 ppm / degreeC or less. The method of claim 1, A manufacturing method using a thermotropic liquid crystal polyester as said liquid crystal polymer. The method of claim 1, In the circuit pattern formation process, the metal circuit pattern is formed by adhering and etching the metal foil which roughened the surface of the side which contacts the said liquid crystal polymer film at least. The method of claim 1, In the circuit pattern forming step, a metal circuit pattern having an elongation value in consideration of deformation in forming a recess in the next step on a plane is formed. The method of claim 7, wherein The manufacturing method which has a shape which curved the metal circuit pattern which has the elongation value which considered the deformation | transformation at the time of forming a recessed part in planar view. The method of claim 8, The manufacturing method which makes a shape curved by planar view substantially radially symmetrical. The method of claim 1, In the recess forming step, a liquid crystal polymer molecular chain is redirected in a part of the wall surface of the recess and in the vicinity of the part, or in the entire wall surface of the recess and in the vicinity of the part. The method of claim 1, In the circuit pattern forming step, the ratio of the area occupied by the metal circuit pattern in the portion to be the wall surface of the recessed portion to be 20 to 90% in the state before forming the recessed portion. As a circuit board precursor for a light emitting body, A metal circuit pattern is formed on the surface of the liquid crystal polymer film, In the circuit pattern, at least one pair of electrode predetermined portions on which the light emitting element is to be mounted is present, and each of the electrode predetermined portions is connected to another circuit in the substrate through a conductive circuit. A circuit board precursor for a light emitting body, characterized in that it is used to form a recess having a bottom portion where the electrode predetermined portion, the conductive circuit should exist, and a wall surface on which the conductive circuit should exist. 13. The method of claim 12, A circuit board precursor for a light emitting body which is used to form a plurality of said recessed parts. The method according to claim 12 or 13, A circuit board precursor for a light emitting body having a plurality of pairs of the electrode predetermined portion. 13. The method of claim 12, The liquid crystal polymer film is a circuit board precursor for a light emitting body, the linear expansion coefficient of the direction parallel to the film plane is adjusted to 25 ppm / ℃ or less. 13. The method of claim 12, The liquid crystal polymer is a thermotropic liquid crystal polyester circuit board precursor for a light emitting body. 13. The method of claim 12, The circuit board precursor for light-emitting bodies in which at least the surface of the side of the said liquid crystal polymer film of the metal foil which comprises the said circuit pattern is harmonized. 13. The method of claim 12, Wherein the conductive circuit has a stretch value on the plane when the liquid crystal polymer film undergoes deformation accompanied with stretching. The method of claim 18, Wherein the conductive circuit has a shape curved in plan view. The method of claim 19, A circuit board precursor for a light emitter wherein said curved shape is substantially radially symmetrical. 13. The method of claim 12, A circuit board precursor for a light-emitting body, wherein the proportion of the area occupied by the metal circuit pattern in the portion to be the wall surface of the recess is 20 to 90% in a state before forming the recess. The recessed portion on which the light emitting element is to be mounted is formed at a portion including the electrode predetermined portion of the circuit board precursor for the light-emitting body according to claim 12, and the conductive circuit is present on the bottom and wall of the recessed portion. A circuit board for light emitting body. The method of claim 22, A part of the wall surface of the recessed portion and the vicinity of the portion, or all of the wall surface of the recessed portion and in the vicinity of the whole portion is such that the elastic modulus is increased by the reorientation of the liquid crystal polymer chain. The method of claim 22 or 23, A long circuit board for light emitters, wherein the circuit board for light emitters is wound in a roll. A light emitter comprising the circuit board for light emitter according to claim 22. The method of claim 25, A light emitter having heat dissipation means on the opposite side of the circuit pattern formation surface of the circuit board for the light emitter.

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