JP2009302110A - Cover ray film - Google Patents

Abstract

[PROBLEMS] To provide high heat resistance, high reflectivity in the visible light region, and low decrease in reflectivity under high-temperature heat load environment. Provide coverlay film.
A composition containing 5 to 100 parts by weight of an inorganic filler with respect to 100 parts by weight of a resin composition comprising a polyaryl ketone resin having a crystal melting peak temperature of 260 ° C. or higher and an amorphous polyetherimide resin. The average reflectance at a wavelength of 400 to 800 nm is 70% or more, and the reduction rate of the reflectance at a wavelength of 470 nm after heat treatment at 200 ° C. for 4 hours is 10% or less. Coverlay film for protecting printed circuit board conductor circuits.
[Selection] Figure 1

Description

  The present invention relates to a printed circuit board, in particular, a coverlay film for protecting a conductor circuit for protecting the surface of a substrate on which a light emitting element such as LDE is mounted, a light emitting element mounting substrate formed by laminating the coverlay film, and a light source device More specifically, the present invention relates to a coverlay film or the like in which a decrease in reflectance is suppressed even under a high-temperature heat load environment or a light resistance test environment.

  Since chip-type LEDs that are mounted directly on the printed circuit board pattern and are resin-sealed are advantageous for miniaturization and thinning, they can be used in electronic devices such as numeric keypad lighting for mobile phones and backlights for small liquid crystal displays. Widely used.

  In recent years, the improvement in the technology for increasing the brightness of LEDs has been remarkably improved, and the LEDs have become more bright, but along with this, the amount of heat generated by the LED elements themselves has increased, and the thermal load on the periphery of the printed circuit board has increased, The LED element ambient temperature is sometimes over 100 ° C. Moreover, in the manufacturing process of the LED mounting substrate, the thermosetting treatment of the sealing resin and the use of lead (Pb) -free solder have progressed, and in the reflow process, a temperature of about 260 to 300 ° C. may be applied. Exposed to thermal environment. Under such a heat load environment, a conventional white photo-curing and thermosetting solder resist is coated to form a white printed wiring board made of a thermosetting resin composition. There is a tendency for the whiteness to decrease and the reflection efficiency to be inferior, such as yellowing of the printed wiring board, and there is still room for improvement as a substrate for mounting next-generation high-brightness LEDs. In addition, products equipped with a white printed wiring board that is coated with a white solder resist are required to have long-term reliability in the future. However, there was a tendency for the reflectance to be inferior. On the other hand, ceramic substrates are superior in heat resistance, but they are hard and brittle, so there is a limit to reducing the area and thickness due to their hard and brittle nature, making it difficult to handle as a substrate for future general lighting and display applications. Of a heat-resistant coverlay film and a printed wiring board formed by laminating a coverlay film that does not discolor under high-temperature heat load, does not deteriorate reflectance, and can handle a large area Development was required.

  In addition, printed circuit boards are formed with precisely designed conductor circuits, etc., using a printing method, and covered with a coverlay film to protect conductor circuits such as insulation, rust prevention, and scratch protection. Has been. For example, Patent Document 1 includes a resin composition containing 65 to 35% by weight of a polyaryl ketone resin having a crystal melting peak temperature of 260 ° C. or higher and 35 to 65% by weight of an amorphous polyetherimide resin, A coverlay film in which the crystallinity of the composition is appropriately advanced is disclosed.

Japanese Patent No. 3514668

  Since a printed circuit board on which a light emitting element such as one or a plurality of LEDs is mounted has a conductor circuit, the conductor circuit needs to be protected. The above-mentioned Patent Document 1 shows characteristics suitable for adhesion to the surface of a printed wiring board when heated to a low temperature of 260 ° C. or lower by utilizing the crystallinity of the thermoplastic resin composition, and in a relatively short time. A cover lay film that can be bonded and exhibits heat resistance that can withstand 260 ° C. after heat fusion is disclosed. In particular, in order to laminate on a printed wiring board on which an LED is mounted, it is described in Patent Document 1. A coverlay film that does not take into account the reflectance cannot be used as it is.

  Therefore, the object of the present invention is to provide a printed wiring especially for LED mounting, which has high heat resistance, high reflectance in the visible light region, and little reduction in reflectance under a high-temperature heat load environment, and can cope with a large area. It is an object of the present invention to provide a coverlay film that can be used for a substrate, and a light emitting element mounting substrate and a light source device formed by laminating the coverlay film.

  The inventors have a composition containing 5 to 100 parts by weight of an inorganic filler with respect to 100 parts by weight of a resin composition comprising a polyaryl ketone resin having a crystal melting peak temperature of 260 ° C. or higher and a polyetherimide resin. The conductor circuit protection of a printed wiring board having an average reflectance at a wavelength of 400 to 800 nm of 70% or more and a reduction rate of the reflectance at a wavelength of 470 nm after a heat treatment at 200 ° C. for 4 hours is 10% or less It has been found that a coverlay film for use in solving the above-mentioned problems has led to the completion of the present invention.

That is, this invention contains 5-100 mass parts of inorganic fillers with respect to 100 mass parts of (1) polyaryl ketone resin whose crystal melting peak temperature is 260 degreeC or more, and polyetherimide resin. A print comprising the composition, wherein the average reflectance at a wavelength of 400 to 800 nm is 70% or more, and the reduction rate of the reflectance at a wavelength of 470 nm after heat treatment at 200 ° C. for 4 hours is 10% or less. A coverlay film for protecting a conductor circuit of a wiring board; and (2) a coverlay according to (1) above, wherein the reflectance reduction rate after the light resistance test shown below is 6% or less. The film or (3) the inorganic filler contains at least a filler having an average particle diameter of 15 μm or less and an average aspect ratio of 30 or more. The coverlay film according to (2), (4) the coverlay film according to any one of (1) to (3), wherein the inorganic filler contains at least titanium oxide, and (5) The coverlay film according to any one of (1) to (4) above, wherein the film has a thickness of 3 to 200 μm, and (6) the average value of the linear expansion coefficients of MD and TD is 35 × 10 ⁻⁶ / ° C. or less, the coverlay film according to any one of the above (1) to (5), and (7) a decrease in reflectance at a wavelength of 470 nm after heat treatment at 260 ° C. for 5 minutes A rate is 10% or less, It is related with the coverlay film in any one of said (1)-(6) characterized by the above-mentioned.
(Light resistance test): irradiation with a xenon weather meter at a temperature of 63 ° C. (black panel temperature), a humidity of 50%, and an irradiance (295 to 400 nm) of 60 W / m ² for 50 hours.

  Moreover, this invention is (8) Light emission characterized by laminating | stacking the coverlay film in any one of said (1)-(7) on the board | substrate which mounts at least 1 or more light emitting element. The present invention relates to an element mounting substrate.

  Furthermore, the present invention provides (9) a cover lay film according to any one of (1) to (7) above, wherein at least one light emitting element is mounted on a wiring board on which a conductor circuit is formed. The light source device includes a light emitting element mounting substrate that is laminated, the light emitting element is resin-sealed, and the wiring board and the light emitting element are electrically connected.

  According to the present invention, a printed wiring board conductor having high heat resistance, excellent dimensional stability, high reflectivity in the visible light region, and low decrease in reflectivity under high-temperature heat load environments and light resistance test environments. A cover-lay film for circuit protection can be provided, and these can be suitably used for a cover-lay film for protecting a conductor circuit of a light-emitting element mounting substrate because of its characteristics.

  Hereinafter, although embodiment of this invention is described, the scope of the present invention is not limited to this embodiment.

(Coverlay film)
As a coverlay film for protecting a conductor circuit of a printed wiring board of the present invention, a resin composition consisting of a polyarylketone resin having a crystal melting peak temperature of 260 ° C. or higher and an amorphous polyetherimide resin is 100 parts by mass. , Composed of a composition containing 5 to 100 parts by weight of an inorganic filler, having an average reflectance of 70% or more at a wavelength of 400 to 800 nm, and a reduction rate of the reflectance at a wavelength of 470 nm after heat treatment at 200 ° C. for 4 hours If the film is 10% or less, the film is not particularly limited, and by adding an inorganic filler, the average reflectance at a wavelength of 400 to 800 nm is set to 70% or more, so that the reflectance is high and in a high temperature heat load environment. An excellent effect that the decrease in reflectance is extremely small can be achieved. Furthermore, by adding a specific inorganic filler, the average value of the linear expansion coefficients of MD (film flow direction) and TD (direction orthogonal to the flow direction) can be 35 × 10 ⁻⁶ / ° C. or less. The cover lay film not only has a high reflectivity but also has a very low decrease in reflectivity under a high-temperature heat load environment, and can have a superior dimensional stability. When the linear expansion coefficient exceeds 35 × 10 ⁻⁶ / ° C., it tends to be curled or warped when laminated on a substrate, and the dimensional stability becomes insufficient. A more preferable range of the linear expansion coefficient is about 10 × 10 ⁻⁶ to 30 × 10 ⁻⁶ / ° C., although it varies depending on the type of substrate used, the circuit pattern formed on the front and back surfaces, and the laminated configuration. Further, the difference in linear expansion coefficient between MD and TD is preferably 20 × 10 ⁻⁶ / ° C. or less, more preferably 15 × 10 ⁻⁶ / ° C. or less, and further 10 × 10 ⁻⁶ / ° C. or less. Most preferably. By reducing the anisotropy (difference between the linear expansion coefficients of MD and TD) in this way, there is no problem of curling or warping on the larger linear expansion coefficient or insufficient dimensional stability.

Moreover, the coverlay film of this invention can make the fall rate of the reflectance after the light resistance test shown below 6% or less. As described above, the cover lay fill of the present invention has not only the heat resistance after heat treatment but also the decrease in reflectance after the light resistance test is extremely small. Can be suitably used.
(Light resistance test): irradiation with a xenon weather meter at a temperature of 63 ° C. (black panel temperature), a humidity of 50%, and an irradiance (295 to 400 nm) of 60 W / m ² for 50 hours.

  As described above, the coverlay film of the present invention requires an average reflectance at a wavelength of 400 to 800 nm to be 70% or more. This is because the higher the reflectance in the visible light region, the higher the luminance of the LED to be mounted. This is because, if it is within the above range, it can be suitably used as a cover lay film for protecting a conductor circuit of an LED mounting substrate. Moreover, since there exists a tendency for a brightness | luminance to become high so that the reflectance of 470 nm vicinity corresponding to the average wavelength (470 nm) of blue LED is high, it is more preferable that the reflectance in 470 nm is 70% or more, and a reflectance is 75%. More preferably.

(Inorganic filler)
Examples of the inorganic filler include talc, mica, mica, glass flake, boron nitride (BN), calcium carbonate, aluminum hydroxide, silica, titanate (potassium titanate, etc.), barium sulfate, alumina, kaolin, Examples include clay, titanium oxide, zinc oxide, zinc sulfide, lead titanate, zircon oxide, antimony oxide, and magnesium oxide. These may be added singly or in combination of two or more.

  Inorganic fillers are those whose surface is treated with silicon compounds, polyhydric alcohol compounds, amine compounds, fatty acids, fatty acid esters, etc., in order to improve dispersibility in thermoplastic resins. Can be used. Among them, those treated with a silicon compound (silane coupling agent) can be preferably used.

(Reflectance adjustment of the coverlay film of the present invention)
As described above, the coverlay film of the present invention has an average reflectance at a wavelength of 400 to 800 nm of 70% or more, and a reflectance reduction rate at a wavelength of 470 nm after heat treatment at 200 ° C. for 4 hours is 10% or less. If the reflectance value falls within this range, the type of inorganic filler added is not particularly limited, but a specific method for bringing the reflectance within the above range is the base. Examples thereof include a method using the filler 1 having a large refractive index difference from the resin composition which is a resin (the refractive index of the filler 1 is generally 1.6 or more). Further, as a specific method for setting the value of the linear expansion coefficient within the above range in consideration of curling prevention and dimensional stability in the lamination with the substrate, the filler 1, the average particle diameter of 15 μm or less, and the average aspect ratio are used. A method using an inorganic filler containing a filler 2 having a ratio (average particle diameter / average thickness) of 30 or more can be mentioned. The content of these inorganic fillers is required to be 5 to 100 parts by mass with respect to 100 parts by mass of the resin composition. Among them, the inorganic filler containing the fillers 1 and 2 is preferably 25 to 100 parts. It is preferable to set it as a mass part. If the amount of the inorganic filler is more than 25 parts by mass, the reflectance and the linear expansion coefficient can be balanced. If the amount is less than 100 parts by mass, the inorganic filler is poorly dispersible or the film is broken when it is formed. It is preferable because there is no case where the problem arises in the property. Thus, by including various fillers (filler 1 and filler 2) having the physical property values specified above as inorganic fillers, good reflectivity and dimensional stability without anisotropy are achieved. An excellent coverlay film can be obtained.

  The filler 1 is an inorganic filler having a large refractive index difference from the resin composition that is a base resin. That is, an inorganic filler having a large refractive index and a reference inorganic filler of 1.6 or more are preferable. Specifically, calcium carbonate, barium sulfate, zinc oxide, titanium oxide, titanate, or the like having a refractive index of 1.6 or more is preferably used, and titanium oxide is particularly preferably used.

  Titanium oxide has a significantly higher refractive index than other inorganic fillers, and can increase the difference in refractive index from the resin composition that is the base resin, so that it is more than when other fillers are used. Excellent reflectivity can be obtained with a small amount. Even if the film is thinned, a white film having high reflectivity can be obtained.

  The titanium oxide is preferably a crystalline titanium oxide such as anatase type or rutile type. Among them, a rutile type titanium oxide is preferable from the viewpoint of a large difference in refractive index from the base resin.

  Moreover, although the manufacturing method of a titanium oxide has a chlorine method and a sulfuric acid method, it is preferable to use the titanium oxide manufactured by the chlorine method from the point of whiteness.

  The titanium oxide is preferably one whose surface is coated with an inert inorganic oxide. By coating the surface of titanium oxide with an inert inorganic oxide, the photocatalytic activity of titanium oxide can be suppressed, and deterioration of the film can be prevented. As the inert inorganic oxide, it is preferable to use at least one selected from the group consisting of silica, alumina, and zirconia. When these inert inorganic oxides are used, a decrease in the molecular weight of the thermoplastic resin and yellowing can be suppressed during high temperature melting without impairing high reflectivity.

  In addition, in order to improve dispersibility in the resin composition, titanium oxide has at least one inorganic compound selected from the group consisting of siloxane compounds, silane coupling agents, etc., a polyol, polyethylene glycol, and the like. Those surfaced with at least one organic compound selected from the group are preferred. In particular, those treated with a silane coupling agent are preferable from the viewpoint of heat resistance.

  The particle size of titanium oxide is preferably 0.1 to 1.0 μm, more preferably 0.2 to 0.5 μm. If the particle size of titanium oxide is in the above range, the dispersibility in the resin composition is good, the interface with it is densely formed, and high reflectivity can be imparted.

  The content of titanium oxide is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and most preferably 25 parts by mass or more with respect to 100 parts by mass of the resin composition. Within the above range, good reflection characteristics can be obtained, and good reflection characteristics can be obtained even when the film is thin.

  Examples of the filler 2 having an average particle diameter of 15 μm or less and an average aspect ratio (average particle diameter / average thickness) of 30 or more are, for example, synthetic mica, natural mica (mascobite, phlogopite, sericite, szolite, etc.), fired In addition, inorganic scale-like (plate-like) fillers such as natural or synthetic mica, boehmite, talc, illite, kaolinite, montmorillonite, vermiculite, smectite, and plate-like alumina, and scale-like titanates can be mentioned. According to these fillers 2, the linear expansion coefficient ratio in the plane direction and the thickness direction can be kept low. In consideration of light reflectivity, scaly titanate is more preferable because of its high refractive index. In addition, the said filler 2 can be used individually or in combination of 2 or more types. By using a scaly filler with a high aspect ratio, moisture permeation (moisture absorption) to the film can be suppressed, oxidation deterioration of the thermoplastic resin in a high heat environment can be prevented, and reduction in reflectance can be suppressed. In addition, the rigidity of the film is improved and the film can be used for a thinner substrate.

  The content of the filler 2 is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and further preferably 30 parts by mass or more with respect to 100 parts by mass of the resin composition. . If it is the said range, it is possible to reduce the linear expansion coefficient of the white film obtained to a desired range.

  As a combination of the filler 1 and the filler 2, it is preferable that the titanium oxide and the scale-like inorganic filler are appropriately blended in order to balance the reflectance and the linear expansion coefficient.

(Resin composition)
The resin composition requires a resin composition containing a polyaryl ketone resin having a crystal melting peak temperature of 260 ° C. or higher and an amorphous polyetherimide resin, and by using the resin composition It is possible to have heat resistance against Pb-free solder reflow. In addition, it is possible to prevent oxidative deterioration in a high heat environment and suppress a decrease in reflectance. In addition, it is possible to suppress a decrease rate in reflectance after a light resistance test using a xenon weather meter.

  Polyaryl ketone resins having a crystal melting peak temperature of 260 ° C. or higher include polyether ether ketone (PEEK: Tg = 145 ° C., Tm = 335 ° C.), polyether ketone (PEK: Tg = 165 ° C., Tm = 355 ° C.). Etc. are preferably used.

  This polyaryl ketone resin is a thermoplastic resin having an aromatic nucleus bond, an ether bond and a ketone bond in its structural unit, and representative examples thereof include polyether ketone, polyether ether ketone, polyether ketone ketone and the like. Among these, from the viewpoint of improving heat resistance, it is preferable to exhibit crystallinity and have a Tm of 260 ° C. or higher, particularly 300 to 380 ° C. Moreover, as long as the effect of this invention is not inhibited, you may contain a biphenyl structure, a sulfonyl group, etc., or another repeating unit.

  Among the polyaryl ketone resins, polyaryl ketone resins mainly composed of a polyether ether ketone having a repeating unit represented by the following structural formula (1) are particularly preferably used. Here, the main component means that the content exceeds 50% by mass. Polyether ether ketone is commercially available as “PEEK151G”, “PEEK381G”, “PEEK450G” (all are trade names of VICTREX), and the like. A polyaryl ketone resin can be used individually or in combination of 2 or more types.

  Moreover, as an amorphous polyetherimide resin, polyetherimide (PEI) etc. which have high Tg whose glass transition temperature is 260 degreeC or more are used suitably.

  Specific examples of the amorphous polyetherimide resin include amorphous polyetherimide resins having a repeating unit represented by the following structural formula (2) or (3).

  The amorphous polyetherimide resin having a repeating unit represented by the structural formula (2) or (3) is composed of 4,4 ′-[isopropylidenebis (p-phenyleneoxy)] diphthalic dianhydride and p- As a polycondensate with phenylenediamine or m-phenylenediamine, it can be produced by a known method. Examples of commercially available products of these polyetherimide resins include “Ultem 1000” (Tg: 216 ° C.), “Ultem 1010” (Tg: 216 ° C.), “Ultem CRS 5001” (Tg 226 ° C.), etc., manufactured by General Electric. Among these, a polyetherimide resin having a repeating unit represented by the structural formula (3) is particularly preferable. In addition, polyetherimide resin can be used individually or in combination of 2 or more types.

  The cover lay film of the present invention contains 20% by mass or more and 80% by mass or less of a polyaryl ketone resin having a crystal melting peak temperature of 260 ° C. or higher when the adhesiveness with a printed wiring board is taken into consideration, and the balance It is preferable to use a mixed composition containing amorphous polyetherimide resin and inevitable impurities. More preferably, they are 30 mass% or more and 75 mass% or less, More preferably, they are 40 mass% or more and 70 mass% or less. By setting the upper limit of the content of the polyaryl ketone resin within the above range, it is possible to suppress the increase in crystallinity of the resin composition constituting the coverlay film, and to prevent a decrease in adhesion to the substrate. it can. Moreover, by setting the lower limit of the content of the polyaryl ketone resin within the above range, it is possible to prevent the crystallinity of the resin composition constituting the cover lay film from being lowered, and to prevent a decrease in heat resistance. it can.

  The cover lay film of the present invention requires that the reflectance decrease rate at a wavelength of 470 nm after heat treatment at 200 ° C. for 4 hours is 10% or less, and above all, the wavelength 470 nm after heat treatment at 260 ° C. for 5 minutes. It is preferable that the reflectance decrease rate at 10% or less.

  The grounds for the above conditions are described below. When manufacturing an LED mounting substrate, a thermosetting process (100 to 200 ° C., several hours) of a sealing agent such as a conductive adhesive, epoxy, or silicon resin, soldering process (Pb-free solder reflow, peak temperature 260 ° C., (Several minutes) and wire bonding process, and so on. Further, even in an actual use environment, development of high-brightness LEDs has progressed, the thermal load on the substrate tends to increase, and the LED element ambient temperature may exceed 100 ° C. in some cases. In the future, it will be important to maintain a high reflectance without discoloration even under such a high heat load environment. The wavelength 470 nm is the average wavelength of the blue LED.

  Therefore, if the rate of decrease in reflectance at a wavelength of 470 nm under the above conditions (200 ° C., 4 hours later, 260 ° C., 5 minutes later) is 10% or less, the light emitting element mounting substrate, the light source device and the like are manufactured. It can be used as a coverlay film for protecting a conductor circuit of an LED mounting board because it is possible to suppress a decrease in reflectivity of the LED and to suppress a decrease in reflectivity during actual use. it can. More preferably, it is 5% or less, More preferably, it is 3% or less, Especially preferably, it is 2% or less.

  The coverlay film of the present invention preferably has a thickness of 3 to 200 μm. More preferably, it is 10-100 micrometers, Furthermore, it is 20-50 micrometers. Within such a range, it can be suitably used as a coverlay film for protecting a conductor circuit of a chip LED mounting substrate used as a surface light source for a mobile phone backlight or a liquid crystal display backlight that is required to be thin. it can.

  In the composition constituting the cover lay film of the present invention, various additives other than other resins and inorganic fillers, for example, heat stabilizers, ultraviolet absorbers, light stabilizers, cores, etc., to the extent that their properties are not impaired. You may mix | blend an agent, a coloring agent, a lubricant, a flame retardant, etc. suitably. The method for preparing the composition is not particularly limited, and a known method can be used. For example, (a) a master in which various additives are mixed at a high concentration (typically 10 to 60% by weight) with an appropriate base resin such as a polyaryl ketone resin and / or an amorphous polyetherimide resin. A batch is prepared separately, the concentration is adjusted and mixed with the resin to be used, and mechanically blended with a kneader or an extruder. (B) Various additives are directly kneaded with the resin to be used. Or a mechanical blending method using an extruder or the like. Among the above mixing methods, the method of preparing and mixing the master batch (a) is preferable from the viewpoint of dispersibility and workability. Furthermore, the surface of the film may be appropriately subjected to embossing, corona treatment or the like for improving handling properties.

  As a method for forming the coverlay film of the present invention, a known method such as an extrusion casting method using a T-die or a calendering method can be adopted, and the film forming property of the sheet is not particularly limited. From the standpoint of stability and productivity, an extrusion casting method using a T die is preferred. The molding temperature in the extrusion casting method using a T-die is appropriately adjusted depending on the flow characteristics and film forming properties of the composition, but is generally about the melting point or higher and 430 ° C. or lower. In addition, when a crystalline resin is used, a crystallization treatment method for imparting heat resistance is not particularly limited. For example, a method of crystallization at the time of extrusion casting (cast crystallization method) or film formation In-line crystallization methods using heat treatment rolls or hot-air ovens (in-line crystallization method) and out-of-film crystallization methods in hot-air ovens or hot presses (outline crystallization methods). it can.

  The light emitting element mounting substrate of the present invention is not particularly limited as long as the coverlay film is laminated on a substrate on which at least one light emitting element is mounted. By laminating the lay film, there is no decrease in the reflectivity of the substrate due to discoloration of the cover lay film after heat treatment and after the light resistance test, and the cover lay film also has an effect as a reflector. It can also contribute to improving the reflectivity.

  The substrate on which the light emitting element is mounted is not particularly limited, and various known substrates can be used. For example, after forming a predetermined conductor pattern on a metal laminate in which a metal layer is laminated on at least one surface of a substrate made of a thermosetting resin or a thermoplastic resin, various wiring boards on which light emitting elements are mounted can be used. . By laminating the cover film of the present invention on a known substrate on which such a light emitting element is mounted, the conductor circuit can be protected without affecting the reflectance of the substrate. Since the film also functions as a reflector, it can contribute to the improvement of the reflectance of the substrate.

  In addition to the above, the cover lay film of the present invention can also be used as a substrate on which a light emitting element is mounted. Specifically, the cover lay film of the present invention is formed to a predetermined thickness (for example, 3 to 500 μm), and after forming a conductor pattern in the same manner as described above, a light emitting element is mounted to form a substrate. According to such a form, the substrate itself on which the light emitting element is mounted can cope with an increase in area because the decrease in reflectance is extremely small even under a high temperature heat load environment or a light resistance test environment. Become. In addition, since conventional substrates made of thermosetting resin contain glass cloth, problems such as voids (bubbles) tend to remain in the manufacturing process, thinning is difficult, and in ceramic substrates However, it is difficult to reduce the thickness due to its hard and brittle nature, but it is possible to reduce the thickness when using a metal laminate made by laminating a metal layer on the coverlay film of the present invention as a substrate for mounting a light emitting element. Therefore, it can be suitably used as a backlight substrate for a mobile phone, which is required to be thin.

  As said metal layer, metal foil with a thickness of about 5-70 micrometers, such as copper, gold | metal | money, silver, aluminum, nickel, tin, can be used, for example. Among these, as the metal foil, a copper foil is usually used, and a metal foil having a surface subjected to chemical conversion treatment such as black oxidation treatment is preferably used. In order to enhance the adhesive effect, it is preferable to use a conductor foil that has been chemically or mechanically roughened in advance on the contact surface (surface to be overlapped) side with the film. Specific examples of the conductor foil that has been subjected to surface roughening treatment include a roughened copper foil that has been electrochemically treated when an electrolytic copper foil is produced. Moreover, about the lamination | stacking method of the said metal foil, a well-known method can be employ | adopted if it is a method by a heating and pressurization as a heat-fusion method without interposing an adhesive layer, It does not specifically limit. However, for example, a heat press method, a heat laminating roll method, an extrusion laminating method in which the extruded resin is laminated with a cast roll, or a method combining these can be suitably employed.

  In addition, when heat dissipation is required as a substrate on which the light emitting element is mounted, there is no particular limitation, but the thermal conductivity of a metal material such as a copper plate or an aluminum plate, a ceramic such as an aluminum nitride, or a graphite plate or the like. It is also possible to improve heat dissipation by combining with a high material. For example, as a composite substrate structure with an aluminum plate, the above-mentioned metal laminate is laminated on the entire surface of the aluminum plate, or a window frame for a cavity (recess) structure is removed from the metal laminate and laminated. If you want to. As for the aluminum used, it is desirable that it is roughened considering the adhesiveness with the resin, but when considering the cavity structure, mirror surface aluminum should be used to efficiently reflect the light from the LED. Is preferred. In terms of improving heat dissipation, it is preferable that the thickness of the film is thin. In addition, if the metal laminate formed by laminating a metal layer on the coverlay film of the present invention is used, the resin flow can be suppressed, and even if mirror surface aluminum is used while maintaining the shape of the cavity structure, adhesion reliability can be maintained. It is possible to ensure the sex.

  The method for producing the light emitting element mounting substrate of the present invention is not particularly limited, and in the case of a double-sided substrate in which metal layers are laminated on both sides, for example, it can be produced according to the method shown in FIG. (In the following embodiments, as the substrate on which the semiconductor element is mounted, a film that is the same film as the coverlay film and is thicker than the coverlay film (hereinafter referred to as a white film) is used. Yes.) As shown in FIG. 1, (a) First, a white film (100) and two copper foils (10) to be a metal layer are prepared, and (b) a copper foil (100) on both sides of the white film (100). 10) is laminated by a vacuum press to produce a metal laminate, and (c) a copper foil (10) is etched or plated on copper to form a wiring pattern (20) to form an LED mounting substrate. (D) On this substrate, the coverlay film (400) of the present invention in which a portion to be mounted with a bonding wire is window-laminated is collectively laminated, and then gold-plated, and (e) the LED (200) is mounted, It is used by being connected to the conductor pattern (20) by the bonding wire (30). In addition, the method for performing window cutting is not particularly limited, and a method using a big die, a router processing method, a laser processing method, and the like can be used.

  Moreover, as shown in FIG. 2, (a) a copper laminate (10) is laminated on one side of the white film (100) to produce a metal laminate, and (b) the copper foil (10) is etched to form a wiring pattern. (20) is formed, gold-plated, and the white film (100) is punched into a cavity frame using a big die (40), (c) the window layed coverlay film (400) of the present invention and wiring An aluminum plate (300) is laminated on the surface opposite to the surface on which the pattern (20) is formed by vacuum pressing to form an LED mounting substrate. (D) The LED (200) is mounted on this substrate and used by being connected to the conductor pattern (20) by the bonding wire (30). Note that the method of punching into the cavity frame is not limited to the method using the Bic die, and for example, it can be formed by router processing or using a laser. In addition, in the said manufacturing method, although the lamination | stacking of the film with a single-sided copper foil ((b) in FIG. 2), a coverlay film, and an aluminum plate is performed collectively, these are laminated | stacked sequentially, and then It is also possible to form a frame and a conductor pattern.

As the light source device of the present invention, at least one light emitting element is mounted on a wiring board on which a conductor circuit is formed, and the cover lay film of the present invention is laminated, and the light emitting element is resin-sealed. The wiring board and the light emitting element are not particularly limited as long as the light emitting element mounting substrate is provided, and the cover circuit film of the present invention is laminated so that the conductor circuit is effectively provided. The light source device of the present invention is used for illumination, projector light source, liquid crystal display device and the like because it can be protected and does not cause a decrease in reflectance even under high temperature heat load environment and light resistance test environment. It can be used for various applications such as backlight devices, in-vehicle applications, and cellular phone applications.
(Example)

  Hereinafter, although an Example and a comparative example demonstrate in more detail, this invention is not limited to these. In addition, the various measured values and evaluation about the film etc. which are shown in this specification were calculated | required as follows.

[Crystal melting peak temperature (Tm)]
Using a differential scanning calorimeter “DSC-7” (manufactured by PerkinElmer), the temperature was determined from a thermograph when 10 mg of a sample was heated at a heating rate of 10 ° C./min according to JIS K7121.

[Average reflectance]
An integrating sphere is attached to a spectrophotometer ("U-4000", manufactured by Hitachi, Ltd.), and the reflectance when the reflectance of the alumina white plate is assumed to be 100% is measured at intervals of 0.5 nm over a wavelength range of 400 nm to 800 nm. It was measured. The average value of the measured values obtained was calculated, and this value was taken as the average reflectance.

[Reflectance after heat treatment]
The obtained white film was heat-treated (crystallization treatment) at a peak temperature of 260 ° C. for 30 minutes in a vacuum press, and then heat-treated in a hot-air circulating oven for 4 hours at 200 ° C. and for 5 minutes at 260 ° C. The reflectance after the treatment was measured in the same manner as described above, and the reflectance at 470 nm was read.

[Measurement of linear expansion coefficient]
Using a thermal stress strain measuring device TMA / SS6100 manufactured by Seiko Instruments Inc., a strip-shaped test piece (length 10 mm) cut out from the film is fixed with a tensile load of 0.1 g, and from 30 ° C. to 5 ° C./min. The temperature dependence was raised to 300 ° C. at a rate of 30 ° C. to 140 ° C. when the thermal expansion amounts of MD (α1 (MD)) and TD (α1 (TD)) were lowered.

[Average particle size]
Using a powder specific surface measuring instrument (transmission method) of model “SS-100” manufactured by Shimadzu Corporation, a sample tube having a cross-sectional area of 2 cm ² and a height of 1 cm was filled with 3 g of sample, and 20 cc with a 500 mm water column. The air permeation time was measured, and the average particle size of titanium oxide was calculated from this.

[Test with xenon weather meter]
Using the xenon weather meter (model: SX-75) manufactured by Suga Test Instruments Co., Ltd., the obtained coverlay film was temperature 63 ° C. (black panel temperature), humidity 50%, irradiance (295 to 400 nm) 60 W. Irradiation was performed at / m ² for 50 hours, and then the reflectance was measured in the same manner as described above, and the reflectance at 470 nm was read.

[Heat resistance test]
A copper foil (18 μm, surface roughened foil) is laminated on one side of the cover lay film, and thermocompression bonded by a vacuum press under the condition of 240 ° C. and 5 MPa for 30 minutes to produce a single-sided copper-clad plate, and the normal state of JIS C 6481 In accordance with the solder heat resistance of the test piece, the copper foil side of the test piece floats in a 260 ° C. solder bath for 10 seconds in a normal state in contact with the solder bath, then is taken out of the solder bath and allowed to cool to room temperature. The presence or absence was visually observed, and the quality was judged. When there was no bulging and peeling, it was marked with ◯, and when there was bulging and peeling, it was marked with ×.

  Produced by the chlorine method with respect to 100 parts by mass of a resin composition consisting of 40% by mass of a polyether ether ketone resin (PEEK450G, Tm = 335 ° C.) and 60% by mass of an amorphous polyetherimide resin (Ultem 1000). Melting composition obtained by mixing 23 parts by mass of synthetic mica with 41 parts by mass of titanium oxide (average particle size 0.23 μm, alumina treatment, silane coupling agent treatment), average particle size 5 μm and average aspect ratio 50 A film having a thickness of 50 μm was prepared at a preset temperature of 380 ° C. using an extruder equipped with a T-die. The evaluation results are shown in Table 1.

  In Example 1, Example 1 was used except that a polyether ether ketone resin (PEEK450G, Tm = 335 ° C.) 60% by mass and an amorphous polyetherimide resin (Ultem 1000) 40% by mass were used. In the same manner, a film having a thickness of 50 μm was produced. The evaluation results are shown in Table 1.

  In Example 1, instead of 41 parts by mass of titanium oxide and 23 parts by mass of synthetic mica, 67 parts by mass of titanium oxide (average particle size 0.23 μm, alumina treatment, silane coupling agent treatment) produced by a chlorine method was used. A film having a thickness of 50 μm was produced in the same manner as in Example 1 except that the composition obtained by mixing was used. The evaluation results are shown in Table 1.

  In Example 1, instead of 41 parts by mass of titanium oxide and 23 parts by mass of synthetic mica, Example 1 was used except that a composition obtained by mixing 25 parts by mass of titanium oxide produced by the chlorine method was used. Similarly, a film having a thickness of 50 μm was produced. The evaluation results are shown in Table 1.

  A film was produced in the same manner as in Example 1 except that the film thickness was 30 μm. The evaluation results are shown in Table 1.

(Comparative Example 1)
Instead of a polyether ether ketone resin (PEEK450G, Tm = 335 ° C.) 40% by mass and an amorphous polyetherimide resin (Ultem 1000) 60% by mass, a polyether ether ketone resin (PEEK450G, Tm) = 335 ° C.) A film having a thickness of 50 μm was produced in the same manner as in Example 1 except that a resin comprising 100% by mass was used. The evaluation results are shown in Table 1.

(Comparative Example 2)
Instead of a resin composition comprising 40% by mass of a polyether ether ketone resin (PEEK450G, Tm = 335 ° C.) and 60% by mass of an amorphous polyetherimide resin (Ultem 1000), an amorphous polyetherimide resin (Ultem) 1000) A film having a thickness of 50 μm was produced in the same manner as in Example 1 except that a resin composed of 100% by mass was used. The evaluation results are shown in Table 1.

(Comparative Example 3)
In Example 1, instead of 41 parts by mass of titanium oxide and 23 parts by mass of synthetic mica, a composition obtained by mixing 39 parts by mass of synthetic mica having an average particle size of 5 μm and an average aspect ratio of 50 was used. A film having a thickness of 50 μm was produced in the same manner as in Example 1. The evaluation results are shown in Table 1.

  As can be seen from the results shown in Table 1, in Examples 3 and 4, in terms of reflectance characteristics, reflectance change after a heating test, reflectance change after UV irradiation, presence or absence of delamination, and heat resistance, All were able to obtain an excellent cover lay film, and in Examples 1, 2, and 5, it was possible to obtain a cover film further excellent in dimensional stability. On the other hand, in Comparative Example 1, since a single polyether ether ketone resin is used, the reflectance change after UV irradiation is large and the crystallization speed is fast. It did not adhere. In Comparative Example 2, a single amorphous polyetherimide resin is used, which is excellent in terms of reflectance change after the heating test and reflectance change after UV irradiation, but the press temperature is 240 ° C. Then, the adhesiveness with the copper foil is not sufficient, and it is not satisfactory from the viewpoint of heat resistance, and it is considered that it is particularly difficult to use as an LED substrate. Furthermore, in Comparative Example 3, since the average reflectance at a wavelength of 400 to 800 nm is 70% or less (40%), it is considered that it is particularly difficult to use as an LED substrate.

It is the figure which showed one Embodiment of the light emitting element mounting substrate of this invention, and its manufacturing method. It is the figure which showed one Embodiment of the light emitting element mounting substrate of this invention, and its manufacturing method.

Explanation of symbols

10 Copper foil 20 Conductor pattern 30 Bonding wire 100 White film 200 LED
300 Aluminum plate 400 Cover lay film

Claims (9)

It consists of a composition containing 5 to 100 parts by weight of an inorganic filler with respect to 100 parts by weight of a resin composition comprising a polyaryl ketone resin having a crystal melting peak temperature of 260 ° C. or higher and an amorphous polyetherimide resin,
The conductor circuit of a printed wiring board having an average reflectance at a wavelength of 400 to 800 nm of 70% or more and a decreasing rate of the reflectance at a wavelength of 470 nm after heat treatment at 200 ° C. for 4 hours is 10% or less Protective coverlay film. The coverlay film according to claim 1, wherein the reflectance reduction rate after the light resistance test shown below is 6% or less.
(Light resistance test): irradiation with a xenon weather meter at a temperature of 63 ° C. (black panel temperature), a humidity of 50%, and an irradiance (295 to 400 nm) of 60 W / m ² for 50 hours. The coverlay film according to claim 1 or 2, wherein the inorganic filler contains at least a filler having an average particle size of 15 µm or less and an average aspect ratio of 30 or more. The coverlay film according to claim 1, wherein the inorganic filler contains at least titanium oxide. The coverlay film according to claim 1, wherein the film has a thickness of 3 to 200 μm. 6. The coverlay film according to claim 1, wherein an average value of linear expansion coefficients of MD and TD is 35 × 10 ⁻⁶ / ° C. or less. The coverlay film according to any one of claims 1 to 6, wherein a reflectance reduction rate at a wavelength of 470 nm after heat treatment at 260 ° C for 5 minutes is 10% or less. A light emitting element mounting substrate, wherein the coverlay film according to claim 1 is laminated on a substrate on which at least one light emitting element is mounted. On the wiring board on which the conductor circuit is formed, at least one light-emitting element is mounted, and the coverlay film according to any one of claims 1 to 7 is laminated,
A light source device comprising: a light emitting element mounting substrate in which the light emitting element is resin-sealed and the wiring substrate and the light emitting element are electrically connected.

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