JP2007106795A - Thermosetting resin composition and semiconductor light-emitting device using the same composition as sealing material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To thermoset an epoxy resin not having cationic curing property or having lower cationic curing property without lowering an epoxy resin content to the utmost. <P>SOLUTION: The present invention provides a thermosetting resin composition having good resistance to ultraviolet light, heat resistance and volume stability, and a semiconductor light-emitting device using the composition as a resin for sealing a semiconductor light-emitting element and having good endurance and stable optical characteristics. The thermosetting resin composition comprises an epoxy resin, a small amount of acid anhydride not exhibiting a function as a curing agent and a cationic curing catalyst in a normal amount used for cationic curing or in an amount smaller than the normal amount. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thermosetting resin composition that is excellent in ultraviolet resistance and heat resistance and has a very small volume change after curing, and a semiconductor light-emitting device using the composition as a sealing material.

  Conventionally, a bisphenol-based epoxy using an acid anhydride-based curing agent as a sealing material for a semiconductor light-emitting device (for example, a light-emitting diode (LED) chip) that emits light in a wavelength (frequency) region from ultraviolet to visible to infrared. Resins have been widely used.

  Such a transparent bisphenol-based epoxy resin has high adhesion to a circuit board on which an LED chip is mounted, a lead frame, and a resin package surrounding the vicinity of the LED chip, and is mechanical to pressure and stress. Although the durability is good, the light transmittance with respect to light in the short wavelength region of ultraviolet to blue is low, so that the light resistance is inferior, and there is a disadvantage that coloring occurs due to light deterioration or heat deterioration.

  By the way, an LED chip that emits ultraviolet light having a main emission peak wavelength of about 350 to 550 nm or light in a short wavelength region of blue light uses a GaN-based compound semiconductor material such as GaN, GaAlN, InGaN, and InAlGaN. It is possible to obtain a high-intensity white LED by combining these LED chips and a fluorescent material.

  In that case, the sealing resin for sealing the LED chip that emits light in the ultraviolet to blue short wavelength region has a high transmittance for light in the short wavelength region so as not to cause a light guide loss. No decrease in transmittance due to heat or light in the short wavelength region included in the emitted light due to self-heating during lighting, transmission due to light in the short wavelength region included in externally irradiated light such as sunlight or illumination light Requirements such as no reduction in rate are required.

  Then, the resin composition which uses a non-aromatic epoxy resin as an active ingredient is proposed as a composition of the sealing resin which seals an LED chip. Specifically, a resin composition for sealing an LED chip containing 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and methylhexahydrophthalic anhydride as active ingredients (see, for example, Patent Document 1) And LED chip sealing resin compositions (for example, see Patent Documents 2 and 3) mainly composed of hydrogenated bisphenol A type epoxy resin and methylhexahydrophthalic anhydride. .

  The cured epoxy resin cured mainly with a non-aromatic epoxy resin with an alicyclic carboxylic acid anhydride has a long carbon-carbon double bond that causes photodegradation. Even if it receives light irradiation over time, a relatively good visible light transmittance can be maintained.

  However, in a semiconductor light-emitting device called a surface-mounted LED, a sealing resin that seals the LED chip is formed in a thin film in order to realize a small size and a thinness, which is one of the features of the surface-mounted LED. Therefore, the use of an acid anhydride-cured epoxy resin may be avoided.

  The reason for this is that acid anhydride curing agents are highly volatile and hygroscopic and slow in curing speed, so when used as a surface mount LED sealing resin, the properties of the cured product fluctuate due to the effects of volatilization and moisture absorption. This is because a good sealing effect may not be obtained. Furthermore, the volume of the sealing resin after curing is reduced due to volatility, sinking occurs on the sealing resin surface that becomes the light emitting surface with respect to the outside of the surface-mounted LED, and the shape of the light emitting surface changes, Therefore, desired optical characteristics such as luminous intensity and orientation characteristics cannot be obtained, and the reproducibility of products with respect to the optical characteristics may be impaired, resulting in variations between products.

  In particular, a fluorescent material that converts the wavelength of at least part of the light emitted from the LED chip is added to a sealing resin that seals the LED chip, and the LED chip is subjected to additive color mixing of the light emitted from the LED chip and the wavelength converted light by the fluorescent material. In a semiconductor light emitting device that emits light of a color tone different from that of the emitted light, the light emitting surface of the LED chip changes from the light emitting surface of the LED chip to the outside of the semiconductor light emitting device in the portion where the volume of the sealing resin after curing is changed Since the optical path length to the sealing resin surface changes, the ratio of the wavelength of light emitted from the LED chip being changed by the fluorescent material changes, and the color tone of the light emitted from the semiconductor light emitting device changes. Become. That is, in the portion where the volume of the sealing resin after curing is reduced, the proportion of light that is wavelength-converted by the fluorescent material is reduced.

  In addition, fluorescent materials generally have the property of diffusing light. Therefore, the diffusion state of the light emitted from the semiconductor light emitting device to the outside is changed by changing the ratio of the wavelength of the light emitted from the LED chip that is converted by the fluorescent material, and the orientation characteristics are also changed. That is, the volume change of the sealing resin after curing becomes a factor that makes the optical characteristics such as emission color and directivity of the semiconductor light emitting device unstable.

  Therefore, a cationic curing agent such as an aromatic sulfonium salt may be used instead of the acid anhydride curing agent. Cationic curing agents have low volatility and have a property of inducing rapid curing as compared with acid anhydride curing agents.

  However, many cationic curing agents have a carbon-carbon double bond such as an aromatic ring as the basic skeleton of the molecule, and they easily absorb light in the short wavelength region below blue and are thermally unstable. It is. That is, a cured product obtained with a cationic curing agent has a problem that yellowing is likely to occur under irradiation of light in a short wavelength region or under a high temperature environment.

As a technology for reducing the amount of catalyst in cationic curing of epoxy resin, a resin composition in which a specific acid anhydride or dicarboxylic acid and a cationic curing agent are added to an epoxy resin mainly composed of an alicyclic epoxy resin. There is one in which the necessary cationic curing catalyst is reduced by heat curing (for example, see Patent Document 4).
JP 2000-196151 A JP 2003-73452 A JP 2003-12896 A JP 2003-176334 A

  In recent years, epoxy resins having various characteristics have been developed as sealing resins for sealing semiconductor light emitting devices, but the cation curability of epoxy resins varies depending on their chemical structure, and can be rapidly increased even at relatively low temperatures. There is a wide variety from those that harden to those that do not react even at high temperatures and cannot provide a self-supporting cured product.

  Therefore, it does not cause yellowing even in the irradiation of light in a short wavelength region or in a high temperature environment, and has no cation curability or a low epoxy resin as a sealing resin for a semiconductor light emitting device. An acid anhydride must be used. However, in that case, since the content of the epoxy resin in the resin composition is lowered, the inherent unique characteristics inherent in the epoxy resin may not be expressed as intended.

  In addition, when used as a sealing resin for a small surface-mount LED having a relatively small specific surface area, the acid anhydride volatilizes and the properties of the cured product fluctuate, and the volume of the sealing resin after curing Due to the decrease, the sealing resin surface that becomes the light emitting surface with respect to the outside of the semiconductor light emitting device becomes extremely concave.

  Therefore, the present invention was devised in view of the above problems, and the object of the present invention is to use an epoxy resin having no or low cationic curability and a cationic curing agent (especially a heat curing agent) in a normal amount or less. It is an object of the present invention to provide a method of curing with a thermal latent catalyst that generates cationic species.

  In particular, tris (2,3-epoxypropyl) isocyanuric acid (hereinafter referred to as TEPIC), which is excellent in UV resistance and heat resistance, is not cationically curable, and a cured product of TEPIC alone by general acid anhydride curing. To make it, 38 parts by weight of TEPIC is mixed with 62 parts by weight of methylhexahydrophthalic anhydride (MH-700, manufactured by Shin Nippon Chemical Co., Ltd.) (corresponding to 0.95 mol relative to the epoxy equivalent).

  Therefore, although a cured product of TEPIC acid anhydride has the above-mentioned problems, the present invention provides a method for curing the TEPIC with a small amount of a cationic curing agent and a small amount of an acid anhydride. An object of the present invention is to realize a sealing resin that does not cause a decrease in volume (resin scale) even if it is used in a device, and to realize a semiconductor light emitting device that employs the sealing resin.

  Moreover, it was made into the subject to implement | achieve the resin cured material which exhibits the outstanding ultraviolet-ray resistance and heat resistance which TEPIC has by obtaining hardened | cured material with much more TEPIC content.

In order to solve the above-mentioned problem, the invention described in claim 1 of the present invention includes: (A) an epoxy resin containing tris (2,3-epoxypropyl) isocyanuric acid represented by the following chemical formula 1; B); 0.001 to 0.3 mol of acid anhydride with respect to the average epoxy equivalent of the epoxy resin, and (C); 0.02 to 0.5 parts by weight of cationic curing with respect to 100 parts by weight of the epoxy resin. It is a thermosetting resin composition containing a catalyst.

In addition, the invention described in claim 2 of the present invention is that, in claim 1, (A); an epoxy resin containing tris (2,3-epoxypropyl) isocyanuric acid represented by the following chemical formula 1, and (B ); A mixture of 0.001 to 0.3 mol of acid anhydride with respect to the average epoxy equivalent of the epoxy resin was heat-treated, and (C); 0.02 to 0 with respect to 100 parts by weight of the epoxy resin. It is a thermosetting resin composition to which 5 parts by weight of a cationic curing catalyst is added.

  According to a third aspect of the present invention, at least a pair of lead electrodes, at least one semiconductor light emitting element electrically connected to the lead electrodes, and sealing for sealing the semiconductor light emitting element A semiconductor light emitting device having a resin, wherein the sealing resin is the thermosetting resin composition according to claim 1.

  According to a fourth aspect of the present invention, in the third aspect, the semiconductor light emitting element is a light emitting diode chip having a main light emission peak wavelength of 550 nm or less.

  Moreover, the invention described in claim 5 of the present invention is that, in claim 4, the thermosetting resin composition absorbs at least a part of light emitted from the light emitting diode chip, and the wavelength of the absorbed light. It contains at least one kind of fluorescent substance that emits light of a different wavelength.

  According to the present invention, a thermosetting resin composition containing a high content of tris (2,3-epoxypropyl) isocyanuric acid excellent in ultraviolet resistance and heat resistance, and causing no volume reduction (resin bique) after curing. In addition, by using the composition as a sealing material for a semiconductor light emitting device, a semiconductor light emitting device having good durability and stable optical characteristics could be realized.

  Tris (2,3-epoxypropyl) isocyanuric acid (TEPIC or triglycidyl isocyanurate) is an epoxy resin having a triazine skeleton, and has excellent heat resistance, chemical resistance, mechanical strength, visible light permeability and weather resistance. Therefore, it is considered promising as a raw material for an LED chip sealing resin that emits light in a short wavelength region.

  The above epoxy resins can be cured with commonly used curing agents such as polyamines, polyamides, and acid anhydrides, but have a stoichiometric composition because they have a lower epoxy equivalent compared to general epoxy resins. The product requires a relatively large amount of curing agent. Therefore, the fact that tris (2,3-epoxypropyl) isocyanuric acid is diluted by the addition of a curing agent means that it is used in a situation where the inherent characteristics are difficult to be exhibited.

  Tris (2,3-epoxypropyl) isocyanuric acid is a trifunctional epoxy resin that is highly reactive with ordinary curing agents and gives a cured product with a high crosslinking density. The cationic curability of the resin composition is very low. Therefore, if such a resin composition can be cured with a catalytic amount of a cationic curing agent, high heat resistance and visible light due to the rigid triazine skeleton of tris (2,3-epoxypropyl) isocyanuric acid can be obtained. A cured product having light transmittance and weather resistance which has become more apparent than before can be obtained.

  Against this background, the higher the tris (2,3-epoxypropyl) isocyanuric acid content represented by the following chemical formula 1 among the epoxy resin components contained in the thermosetting resin composition of the present invention, the characteristics Can be obtained, but diluted with different epoxy resin components and resin modifiers to meet other required properties such as flexibility and toughness required for LED chip sealing resin It does not prevent.

  Epoxy resins effective for diluting tris (2,3-epoxypropyl) isocyanuric acid include various alicyclic epoxy resins, aliphatic epoxy resins, hydrogenated bisphenol A diglycidyl ether, hexahydrophthalic acid, which are excellent in UV resistance. Examples include diglycidyl ester and epoxy-modified tetramethyldisiloxane. However, the epoxy resin that can be used for dilution in the present invention is not limited to these, and these may be used by appropriately mixing them. Moreover, it does not prevent supplementing an epoxy resin having a small amount of carbon-carbon double bonds within a range that does not impair the durability required as a sealing resin. Furthermore, the use of oxetane resins or various modified resins copolymerizable with epoxy resins is not limited.

  As for the quantity of the acid anhydride which the thermosetting resin composition of this invention contains, it is desirable that it is 0.001-0.3 mol with respect to the average epoxy equivalent of the epoxy resin to contain. When the ratio of the acid anhydride to the epoxy equivalent is less than 0.001 mol, it becomes a cause of curing failure, and in an extreme case, it is not cured. Conversely, if the ratio of acid anhydride to epoxy equivalent is greater than 0.3 mol, the resin volume decrease (resin bake) associated with vaporization of acid anhydride when sealing small surface-mount LEDs can be ignored. Disappear.

  The acid anhydride constituting the present invention can be appropriately selected from those not containing a carbon-carbon double bond in consideration of ultraviolet resistance. Suitable acid anhydrides are exemplified in the following chemical formulas 2 to 5, but the acid anhydrides constituting the present invention are not limited to these, and they may be used by appropriately mixing them.

  As the cationic curing agent (catalyst) contained in the thermosetting resin composition of the present invention, aromatic sulfonium salts, aromatic diazonium salts, aromatic iodonium salts, aromatic selenium salts, and the like can be used. It is most preferable to use an aromatic sulfonium hexafluoroantimony salt. Moreover, it is desirable that the amount of the cationic curing agent is 0.02 to 0.5 parts by weight with respect to 100 parts by weight of the epoxy resin contained in the thermosetting resin composition of the present invention. When the amount of the curing agent is 0.02 parts by weight or less, it takes a long time for curing, or treatment at a higher temperature is required, which causes coloring of the cured product. In addition, when the amount of the curing agent is 0.5 parts by weight or more, the property of easily causing yellowing in a short wavelength region of light irradiation or a high temperature environment, which is a defect of a cationically cured epoxy resin cured product, appears significantly. .

  The thermosetting resin composition of the present invention comprises (A): an epoxy resin containing tris (2,3-epoxypropyl) isocyanuric acid represented by the following chemical formula 1, and (B); functioning alone as a curing agent. It contains a small amount of an acid anhydride that does not exhibit, and (C) a normal or lower amount of a cationic curing catalyst used for cationic curing. It is also possible to prepare a mixture of (A), (B) and (C) at a time and heat cure the composition as it is. As another method, a mixture of (A) and (B) is preheated to react a epoxy resin and an acid anhydride to form a crosslinked oligomer that retains fluidity, and then a cationic curing agent as component (C) It is also possible to finally obtain a thermosetting product having translucency by adding. Tris (2,3-epoxypropyl) isocyanuric acid is a powdery epoxy resin at room temperature, and when a resin composition having a high content is thermally cured at one time, tris (2,3-epoxypropyl) isocyanuric acid Since the melting and curing reaction proceed simultaneously, uniform mixing is difficult and it is easy to cause curing unevenness. Therefore, curing by the above-mentioned alternative method is recommended.

  By the way, an object of the present invention is to provide a thermosetting resin composition containing a high content of tris (2,3-epoxypropyl) isocyanuric acid excellent in ultraviolet resistance and heat resistance and causing no resin viking, and the composition It is to provide a semiconductor light emitting device using an object as a sealing material for a semiconductor light emitting element. Therefore, within a range not departing from this object, the resin composition is at least selected from the group consisting of a wavelength converting fluorescent substance, an inorganic filler, an antioxidant, a light stabilizer, a resin modifier, and a silane coupling agent. Does not prevent the inclusion of one.

  In order to further improve the heat resistance stability of the cured product provided by the thermosetting resin composition of the present invention, it is recommended that the composition contains an antioxidant as an additive. In that case, examples of the antioxidant include phenolic antioxidants (2,6-di-tert-butyl-p-cresol (hereinafter referred to as BHT)), sulfur antioxidants (mercaptopropionic acid derivatives, etc.). ), Phosphorus antioxidants (9,10-dihydro-9-oxa-10-phosphophenanthrene-10-oxide (hereinafter referred to as HCA)) and the like. Among these, it is preferable to use a phenol-based antioxidant, and it is more preferable to use a phenol-based antioxidant in combination with a relatively small amount of a sulfur-based antioxidant.

  As content of the phenolic antioxidant in the resin composition of this invention, it is about 0.1-4 weight part normally with respect to a total of 100 weight part of a composition component, Preferably it is 0.2-2 weight About 1 part, more preferably about 0.5 to 1 part by weight. When a sulfur-based antioxidant is used in combination, it is recommended that the content be suppressed to about 0.1 parts by weight with respect to 100 parts by weight of the total composition components.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3 (the same parts are denoted by the same reference numerals). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  Therefore, a plate-like plate having a thickness of 2 mm was prepared for each of the two examples and the four comparative examples, and a side-view type surface-mounted LED described later was manufactured for a part of the plate-like plate, and an evaluation of each was attempted.

  High-purity grade tris (2,3-epoxypropyl) isocyanuric acid (TEPIC-S manufactured by Nissan Chemical Industries, Ltd.) 100 parts by weight, methylhexahydrophthalic anhydride (MH-700 manufactured by Shin Nippon Rika Co., Ltd.) 6 parts by weight (corresponding to 0.01 mol with respect to the epoxy equivalent of TEPIC) and 0.5 parts by weight of a phenolic antioxidant (BHT) were mixed and subjected to a preheating treatment at 130 ° C. for 1 hour. Next, 0.5 parts by weight (Adeka Opton CP-77 manufactured by Asahi Denka Kogyo Co., Ltd.) was added and the resin composition mixed with stirring was poured into a resin shaping mold and heated at 150 ° C. for 1 hour and 180 ° C. for 3 hours. A curing treatment was performed to obtain a slightly yellowish translucent cured product (resin plate having a thickness of 2 mm).

  High-purity grade tris (2,3-epoxypropyl) isocyanuric acid (TEPIC-S manufactured by Nissan Chemical Industries, Ltd.) 57 parts by weight, hexahydrophthalic acid diglycidyl ester (SR-HHPA manufactured by Sakamoto Pharmaceutical Co., Ltd.) 43 parts by weight Parts, 1.6 parts by weight of methylhexahydrophthalic anhydride (manufactured by Shin Nippon Rika Co., Ltd., MH-700) (corresponding to 0.011 mol with respect to the average epoxy equivalent), 0.5 parts of phenolic antioxidant (BHT) Part by weight and 0.1 part by weight of a phosphorus-based antioxidant (HCA) were mixed and subjected to a preheating treatment at 130 ° C. for 1 hour. Next, a resin composition obtained by adding 0.2 parts by weight of a cationic curing agent (SI-100L, manufactured by Sanshin Chemical Industry Co., Ltd.) and stirring and mixing the resin composition of a resin mold and a side-view type surface mount LED package. The resin was injected into each part (injection amount of resin per LED; 1 microliter) and subjected to thermosetting treatment at 130 ° C. for 1 hour and 150 ° C. for 5 hours to give a colorless and transparent cured product (2 mm thick resin plate and side view) A sealing resin part of a type surface mount LED) was obtained.

The 2 mm thick resin plate obtained in Example 2 was subjected to the evaluation test of the following items, and the results were confirmed.
(1) Transmittance: The transmittance for light in the visible light region was 90% or more.
(2) Ultraviolet resistance: Light with a wavelength of 365 nm from a high-pressure mercury lamp was irradiated for 48 hours at an intensity of 5000 mW / cm ^{2 in} an atmosphere of 60 ° C. As a result, no coloring or deterioration was observed.
(3) Heat resistance: left in a thermostatic bath at 150 ° C. for 48 hours. As a result, no yellowing was observed.
Therefore, from the evaluation test results of ultraviolet resistance and heat resistance, it was confirmed that the durability required for the LED chip sealing resin emitting light in the short wavelength region was satisfied.

  Moreover, about the side view type surface mount type LED obtained in Example 2, the sealing state was confirmed with the stereomicroscope. As a result, no depression of the sealing resin surface due to the resin viquet and no peeling or cracking of the sealing resin were observed.

  That is, conventionally, the TEPIC content could not be increased to 38% or more while maintaining good resin properties of TEPIC. However, according to the present invention, a TEPIC content of 38% or higher can be achieved, and the TEPIC content is about 57%. % UV-resistant and heat-resistant resin cured product can be realized.

[Comparative Example 1]
High-purity grade tris (2,3-epoxypropyl) isocyanuric acid (TEPIC-S manufactured by Nissan Chemical Industries, Ltd.) 100 parts by weight, phenolic antioxidant (BHT) 0.5 part by weight, and (Asahi Denka Kogyo Co., Ltd.) Company Adeka Opton CP-77) 0.5 parts by weight is heated and dissolved at 130 ° C., and the resin composition, which is well stirred and mixed, is poured into a resin shaping mold and heat-cured at 150 ° C. for 1 hour and 180 ° C. for 5 hours. However, a self-supporting cured product was not obtained. In other words, it was found that TEPIC cannot obtain a cured product only with a cationic curing agent and does not have cationic curability.

[Comparative Example 2]
High-purity grade tris (2,3-epoxypropyl) isocyanuric acid (TEPIC-S manufactured by Nissan Chemical Industries, Ltd.) 57 parts by weight, hexahydrophthalic acid diglycidyl ester (SR-HHPA manufactured by Sakamoto Pharmaceutical Co., Ltd.) 43 parts by weight Parts, phenolic antioxidant (BHT) 0.5 parts by weight, phosphorus antioxidant (HCA) 0.1 parts by weight, and cationic curing agent (SI-100L, manufactured by Sanshin Chemical Industry Co., Ltd.) 0.5 parts by weight The part was heated and melted at 130 ° C., and the resin composition mixed well with stirring was poured into a resin mold and subjected to thermosetting treatment at 130 ° C. for 1 hour and 150 ° C. for 5 hours. However, a self-supporting cured product was not obtained.
In other words, it was found that TEPIC cannot obtain a cured product only with a cationic curing agent and does not have cationic curability.

[Comparative Example 3]
High-purity grade tris (2,3-epoxypropyl) isocyanuric acid (TEPIC-S manufactured by Nissan Chemical Industries, Ltd.) 38 parts by weight, methylhexahydrophthalic anhydride (MH-700 manufactured by Shin Nippon Rika Co., Ltd.) 62 parts by weight Parts (corresponding to 0.95 mol with respect to epoxy equivalent), 0.5 parts by weight of phenolic antioxidant (BHT), and 0.1 parts by weight of phosphorus antioxidant (HCA) were mixed at 130 ° C., Pre-heating treatment was performed for a minute. Next, a resin composition obtained by adding 0.2 parts by weight (Hishikorin PX-4ET, manufactured by Nippon Kagaku Kogyo Co., Ltd.) as a curing accelerator and stirring and mixing the resin composition is used as a resin mold and a side view type surface mount LED package resin. It is injected into the molding part (injection amount of resin per LED: 1 microliter) and subjected to thermosetting treatment at 120 ° C. for 1 hour and 150 ° C. for 3 hours to give a colorless and transparent cured product (2 mm thick resin plate and side A sealing resin portion of a view-type surface-mounted LED) was obtained.

  Moreover, about the side view type surface mount type LED obtained by the comparative example 3, the sealing state was confirmed with the stereomicroscope. As a result, some cracks were observed, and significant concavity due to resin viquet was observed on the sealing resin surface.

  This Comparative Example 3 is a general condition when a cured product of TEPIC alone as an epoxy resin is obtained by acid anhydride curing. However, when the cured product according to this condition is used as a sealing material, there is a problem of cracks and resin blisters. It was confirmed that it occurred.

[Comparative Example 4]
High-purity grade tris (2,3-epoxypropyl) isocyanuric acid (TEPIC-S, manufactured by Nissan Chemical Industries, Ltd.) 25 parts by weight, hexahydrophthalic acid diglycidyl ester (SR-HHPA, manufactured by Sakamoto Pharmaceutical Co., Ltd.) 19 weights Parts, 56 parts by weight of methyl hexahydrophthalic anhydride (manufactured by Shin Nippon Rika Co., Ltd., MH-700) (corresponding to 0.91 mol with respect to the average epoxy equivalent), 0.5 parts by weight of phenolic antioxidant (BHT) And 0.1 part by weight of a phosphorus-based antioxidant (HCA) were mixed and subjected to a preheating treatment at 130 ° C. for 10 minutes. Next, a resin composition obtained by adding 0.2 parts by weight (Hishikorin PX-4ET, manufactured by Nippon Kagaku Kogyo Co., Ltd.) as a curing accelerator and stirring and mixing the resin composition is used as a resin mold and a side view type surface mount LED package resin. It is injected into the molding part (injection amount of resin per LED: 1 microliter) and subjected to thermosetting treatment at 120 ° C. for 1 hour and 150 ° C. for 3 hours to give a colorless and transparent cured product (2 mm thick resin plate and side A sealing resin portion of a view-type surface-mounted LED) was obtained.

  Moreover, about the side view type surface mount type LED obtained by the comparative example 4, the sealing state was confirmed with the stereomicroscope. As a result, although peeling and cracks were not recognized, remarkable concavity due to resin viquet was observed on the sealing resin surface.

  From the viewpoints of UV resistance and heat resistance, a higher TEPIC content is preferable, but when other epoxy resins were mixed to improve mechanical properties, mechanical properties could be improved, but resin vices were eliminated. Was not.

  As mentioned above, although the Example concerning the resin composition of this invention was demonstrated with the comparative example, next, an example is given and demonstrated about the semiconductor light-emitting device which uses the thermosetting resin composition of this invention as a sealing material.

  The semiconductor light emitting devices shown in FIGS. 1 and 2 are both called surface-mount semiconductor light-emitting devices, and FIG. 1 shows a top-view type surface-mount semiconductor light-emitting device, which is shown in FIG. One is called a side-view type surface-mount semiconductor light-emitting device.

  First, the top view type surface mount semiconductor light emitting device shown in FIG. 1 will be described. A pair of circuit patterns 2a and 2b are formed on opposite edges of one surface side (surface side) of an insulating base material 1 made of paper phenol, paper epoxy, glass epoxy, etc., and each circuit pattern 2a, 2b goes from the edge of the insulating base material 1 to the other surface side (back surface side) through the side surface side. Further, from each of the pair of circuit patterns 2a and 2b formed on both opposing edges on the surface side of the insulating base material 1, a circuit is directed toward the inside of the insulating base material 1 so as to face each other at a predetermined interval. The pattern extends, and a die bonding pad 3 and a wire bonding pad 4 are formed at each end.

  Then, the LED chip 6 is placed on the die bonding pad 3 via the conductive adhesive 5, and the lower electrode of the LED chip 6 and the circuit pattern 2a are electrically connected. On the other hand, the upper electrode of the LED chip 6 is connected to the wire bonding pad 4 via the bonding wire 7, and electrical connection between the upper electrode of the LED chip 6 and the circuit pattern 2b is achieved.

  Further, the LED chip 6 and the bonding wire 7 are sealed with a sealing resin 8, and the main light output surface 9 of the sealing resin 8 positioned above the LED chip 6 is the main light output surface 10 of the LED chip 6. And is formed in a plane shape substantially parallel to.

  Next, the side view type surface mount semiconductor light emitting device shown in FIG. 2 will be described. A pair of plate-like lead frames 20a, 20b is insert-molded with resin to form a package, and a resin-molded portion 21 of the package is provided with a recess 23 having an opening 22.

  Further, one end of each of the lead frames 20a and 20b is exposed on the inner bottom surface of the recess 23 so as to face each other, and an LED chip is disposed on the exposed one lead frame 20a via a conductive adhesive. 6 is placed, and the lower electrode of the LED chip 6 and the lead frame 20a are electrically connected. On the other hand, the upper electrode of the LED chip 6 is connected to the other lead frame 20b exposed on the inner bottom surface of the recess 23 through the bonding wire 7, and electrical connection between the upper electrode of the LED chip 6 and the lead frame 20b is achieved. ing.

  Further, the recess 23 is filled with the sealing resin 8, and the LED chip 6 and the bonding wire 7 are resin-sealed with the sealing resin 8, and the light emission of the sealing resin 8 located above the LED chip 6 is performed. The surface 24 is formed in a planar shape substantially parallel to the main light emitting surface 10 of the LED chip 6 and substantially flush with the opening end surface 25 of the recess 23.

  The other end side of each of the lead frames 20a and 20b whose one end is exposed at the inner bottom surface of the recess 23 of the resin molding portion 21 protrudes outward from the opposite side surface of the resin molding portion 21 and is resin in the vicinity of the protrusion. It is bent along the side surface of the molding portion toward the opening 22, and further bent in the vicinity of the opening 22 toward the opening 22 at a substantially right angle with the outer edge of the opening 22 as a fold.

  In addition, in the said Example 2, the comparative example 3, and the comparative example 4, the side view type surface mount-type LED which injected the resin composition as a sealing material and performed the evaluation test is shown in FIG.

  In any case, the surface-mount type semiconductor light emitting device shown in FIGS. 1 and 2 is one of the requirements for miniaturization and thickness reduction, and the volume of the sealing material relative to the volume of the resin molded portion of the package. Is relatively high. Therefore, in the conventional sealing material, the resin viquet due to the volume reduction of the sealing resin appears after curing, which affects various optical characteristics.

  By the way, the purpose of resin-sealing the LED chip and the bonding wire with the sealing resin is to protect the LED chip from the external environment such as moisture, dust and gas, and to protect the bonding wire from mechanical stress such as vibration and impact. In addition, the sealing resin forms an interface with the light emitting surface of the LED chip, and also has a function of efficiently emitting the emitted light of the LED chip from the light emitting surface of the LED chip into the sealing resin. ing. Therefore, a material having a high refractive index, good durability, and high light transmittance is generally used for the sealing resin.

  In addition, a phosphor material is mixed into the thermosetting resin composition of the present invention to form a sealing resin, and the phosphor material is excited with a part of the light emitted from the LED chip to convert the wavelength, and the light emitted from the LED chip Can realize a semiconductor light emitting device that emits light of different colors.

  For example, when the light emitted from the LED chip is blue light, a part of the blue light emitted from the LED chip can be obtained by using a fluorescent material that is excited by the blue light and converts the wavelength to yellow light that is a complementary color of blue. Can produce white light by additive color mixing of yellow light wavelength-converted by exciting the fluorescent material and blue light emitted from the LED chip.

  Similarly, when the light emitted from the LED chip is blue light, by using a mixture of two types of phosphor materials that are excited by the blue light and wavelength-converted into green light and red light, respectively, It is also possible to produce white light by additive color mixing of green light and red light, which have been wavelength-converted by a part of the emitted blue light exciting the fluorescent material, and blue light emitted from the LED chip.

  In addition, when the light emitted from the LED chip is ultraviolet light, the LED chip is obtained by using a mixture of three kinds of fluorescent materials that are excited by ultraviolet light and respectively convert the wavelength into blue light, green light, and red light. It is also possible to produce white light by additive color mixing of blue light, green light and red light, which is wavelength-converted by exciting a fluorescent material with a part of ultraviolet light emitted from the light.

  Furthermore, light of various colors other than white light can be created by appropriately combining the wavelength of light emitted from the LED chip and one or more types of fluorescent materials.

  In this case, as shown in FIG. 3, there is a difference in the optical path length from the main light exit surface of the LED chip to the light exit surface of the sealing resin (optical path difference) between the case where the sealing resin has resin bique and the case where the resin resin is not. Occurs. Then, the ratio of wavelength conversion by the fluorescent material mixed in the sealing resin before the light emitted from the LED chip reaches the light emitting surface of the sealing resin is changed, and the light is emitted from the light emitting surface of the sealing resin to the outside. The color tone of the emitted light will change.

  In addition, fluorescent materials generally have the property of diffusing light. Therefore, the diffusion state of the light emitted from the semiconductor light emitting device to the outside is changed by changing the ratio of the wavelength of the light emitted from the LED chip that is converted by the fluorescent material, and the orientation characteristics are also changed.

  In other words, the semiconductor light emitting device in which the LED chip is resin-sealed with a sealing resin having a property of causing a volume change after curing becomes unstable in optical characteristics such as color tone.

  On the other hand, by making the thermosetting resin composition of the present invention resin-sealed for LED chips, volume change of the sealing resin is suppressed, and depression of the surface of the sealing resin due to resin viquet is suppressed. As a result, since the shape of the light emission surface of the sealing resin is kept constant, it is possible to ensure stable optical characteristics such as luminous intensity and orientation.

  Moreover, the volume change of the sealing resin is suppressed by using the thermosetting resin composition mixed with the fluorescent substance of the present invention as the resin sealing of the LED chip, and the depression of the sealing resin surface due to the resin viquet is suppressed. The As a result, since the optical path length from the light emitting surface of the LED chip to the sealing resin surface that becomes the light emitting surface to the outside of the semiconductor light emitting device is kept constant, stable optical characteristics such as emission color and orientation are ensured. can do.

  As described above, by using the thermosetting resin composition of the present invention which is excellent in ultraviolet resistance and heat resistance and does not cause resin viking after curing as a sealing resin for LED chips, the durability is good and stable. A semiconductor light emitting device having optical characteristics can be realized.

It is a perspective view of the semiconductor light-emitting device using the resin composition of this invention. Similarly, it is a perspective view of another semiconductor light-emitting device using the resin composition of the present invention. It is a reference figure which shows the state which resin-sealed the LED chip with resin which mixed the fluorescent substance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Insulation base material 2a, 2b Circuit pattern 3 Die bonding pad 4 Wire bonding pad 5 Conductive adhesive 6 LED chip 7 Bonding wire 8 Sealing resin 9 Main light output surface 10 Main light output surface 20a, 20b Lead frame 21 Resin molding Part 22 Opening 23 Recessed part 24 Light exit surface 25 Opening end face

Claims (5)

(A); an epoxy resin containing tris (2,3-epoxypropyl) isocyanuric acid represented by the following chemical formula 1, and (B); 0.001 to 0.3 mol of the average epoxy equivalent of the epoxy resin A thermosetting resin composition comprising an acid anhydride and (C); 0.02 to 0.5 parts by weight of a cationic curing catalyst with respect to 100 parts by weight of an epoxy resin.

(A); an epoxy resin containing tris (2,3-epoxypropyl) isocyanuric acid represented by the following chemical formula 1, and (B); 0.001 to 0.3 mol of the average epoxy equivalent of the epoxy resin 2. The heat treatment of a mixture with an acid anhydride, wherein 0.02 to 0.5 parts by weight of a cation curing catalyst is added to (C); 100 parts by weight of an epoxy resin. The thermosetting resin composition as described.

  A semiconductor light emitting device comprising at least a pair of lead electrodes, at least one semiconductor light emitting element electrically connected to the lead electrodes, and a sealing resin for sealing the semiconductor light emitting element, wherein the sealing resin Is a thermosetting resin composition according to any one of claims 1 and 2. A semiconductor light-emitting device characterized by the above.   4. The semiconductor light emitting device according to claim 3, wherein the semiconductor light emitting element is a light emitting diode chip having a main emission peak wavelength of 550 nm or less.   The thermosetting resin composition contains at least one kind of fluorescent material that absorbs at least a part of light emitted from the light emitting diode chip and emits light having a wavelength different from the wavelength of the absorbed light. The semiconductor light-emitting device according to claim 4.

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