JP2011178898A - Urethane resin composition, cured object and photosemiconductor device using cured object - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rigid cured object having a high glass transition temperature and excellent uniformity in transparency, and to provide a photosemiconductor device using the same, and a urethane resin composition providing those. <P>SOLUTION: The urethane resin composition comprises a liquid A containing a polyol component and a liquid B containing a polyisocyanate component, wherein the liquid A contains a tri- or higher functional polyol compound having a hydroxyl value of 600-1,300 mgKOH/g and a molecular weight of ≤400. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a urethane resin composition, a cured body, and an optical semiconductor device using the cured body, and more specifically, a urethane resin composition including a polyol component and a polyisocyanate component, a cured body, and an optical semiconductor using the cured body. Relates to the device.

  In the optical semiconductor device, the sealing member is molded by curing the resin composition in order to protect the optical semiconductor element. The resin composition is usually cured and molded by a potting method in which the resin composition is cast in a case or in a lead frame cavity, or in a liquid transfer molding in which the resin composition is filled in a cavity formed by a molding die in a molding apparatus. Or compression molding method. At this time, a hard transparent resin is required in a structure in which the shape of the optical semiconductor device is formed only by the transparent resin and the lead frame, or in a structure in which the lens shape is formed by the transparent resin.

  Moreover, in order to ensure various mounting reliability, it is preferable that the glass transition temperature of the cured body is high. In order to obtain a hardened body having a high glass transition temperature, it is common to set the crosslink density high. In order to obtain a high crosslinking density even in the urethane resin system, it is effective to contain a polyfunctional polyol compound having a short chain length in the polyol component. In Non-Patent Document 1, an example in which trimethylolpropane or glycerin is contained in the polyol component. It is shown.

Journal of Wuhan University of Technology Mater. Sci. Ed Vol. 20, no. 2. Jun. 2005, 24-28

  However, polyols such as trimethylolpropane and glycerin have problems such as poor polarity and compatibility with the isocyanate component, and poor steric hindrance and poor reactivity with the isocyanate component. In particular, when the above polyol is used in combination with another polyol compound, there is a tendency that a uniform cured body is difficult to obtain, such as fluctuations in the cured body due to the difference in reactivity.

  Also in the urethane resin, it is known to use a polyfunctional polyol having a short chain length in order to obtain a high crosslinking density. However, when the amount introduced is large, it is difficult to obtain a uniform cured product due to the difference in reactivity with other polyol compounds, and there are problems such as the generation of bubbles presumed to be caused by uncured components.

  As described above, when the introduction ratio of the short-chain-length polyfunctional polyol is increased, a hardened body having a high glass transition temperature can be obtained, but the uniformity of the cured body tends to be inferior, and both of them are not necessarily at a high level. It was not retained.

  This invention is made | formed in view of the said situation, and it aims at providing the urethane resin composition which can obtain the hardening body which is hard, has a high glass transition temperature, and is excellent in uniformity.

  In the present invention, a urethane resin composition comprising a liquid A containing a polyol component and a liquid B containing a polyisocyanate component, the liquid A having a hydroxyl value of 600 mgKOH / g to 1300 mgKOH / g and a molecular weight of 400 or less. A urethane resin composition comprising a trifunctional or higher functional polyol compound. A cured product obtained from such a urethane resin composition is hard, has a high glass transition temperature, and is excellent in uniformity.

  The reason why the cured product is hard and can achieve both high glass transition temperature and uniformity by the urethane resin composition of the present invention is not necessarily clear, but the present inventors consider as follows. That is, when the polyol component preferably constitutes 80% by mass or more by a polyol compound having a hydroxyl value of 600 mgKOH / g or more and 1300 mgKOH / g or less and a molecular weight of 400 or less, a plurality of polyol components having different reactivity It is considered that a more uniform cured body can be obtained while maintaining the hardness and the glass transition temperature because the difference in reactivity between the polyol species is smaller than the case where the polyol is composed of the polyols.

  The polyisocyanate component has an alicyclic group and two or three isocyanate groups, and at least one isocyanate group is bonded to a secondary carbon constituting the alicyclic group. It is preferable to contain 30% by mass or more of the compound. When the polyisocyanate component contains a polyisocyanate having such a structure, the glass transition temperature of the obtained cured product can be further improved.

  The polyol compound is preferably a compound obtained by adding propylene oxide, ethylene oxide or caprolactone to trimethylolpropane or propane-1,2,3-triol.

  The polyol compound is preferably a compound obtained by adding 1 to 2 moles of propylene oxide to 1 mole of trimethylolpropane.

  Moreover, it is preferable that content of the said polyol compound is 80 mass% or more with respect to the whole quantity of the said polyol component. By containing in the said range, the hardness and glass transition temperature of a hardening body can be made high, and a uniform hardening body can be obtained with sufficient balance simultaneously.

  Moreover, the said A liquid or B liquid contains the saturated fatty acid represented by the following general formula (1), or the weight average molecular weight represented by the said saturated fatty acid and the following general formula (2) is 16000 or less. It is preferable to further include a silicone-caprolactone block copolymer.

In the formula, R ¹ represents a linear or branched hydrocarbon group having 7 to 28 carbon atoms.

In the formula, m and n are positive integers satisfying m / n of 0.5 to 1.0. R ² and R ³ each independently represent a divalent hydrocarbon group or a polyether chain.

  Both the saturated fatty acid and the silicone-caprolactone block copolymer function as a release agent. The liquid A or liquid B further contains these compounds, so that when the urethane resin composition is molded to obtain a cured product, the adhesive with the silver plating is not impaired and the mold is separated from the mold for molding. The moldability can be improved.

  Moreover, it is preferable that the said A liquid or the said B liquid further contains an inorganic filler. By further including an inorganic filler, the thermal expansion coefficient of the cured body can be brought close to the thermal expansion coefficient of the lead frame, and separation from the lead frame can be made difficult to occur in a heat resistance test and a temperature cycle test.

  Moreover, it is preferable that the said A liquid or the said B liquid further contains the adhesiveness imparting agent with silver plating or palladium plating. By improving the adhesiveness with silver plating or palladium plating, it is possible to make it difficult to peel off from the lead frame in a heat resistance test or a temperature cycle test.

  The present invention further provides an optical semiconductor device comprising a sealing member made of a cured product of the urethane resin composition. Such an optical semiconductor device has high optical transparency and uniformity of the cured body, and is excellent in optical characteristics such as light-resistant coloring and mechanical characteristics.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the urethane resin composition which can obtain the hardened | cured body which is hard, has a high glass transition temperature, and is excellent in uniformity.

It is sectional drawing which shows one Embodiment of an optical semiconductor device.

  Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

The urethane resin composition of the present embodiment is a urethane resin composition comprising a liquid A containing a polyol component and a liquid B containing a polyisocyanate component. The liquid A has a hydroxyl value of 600 mgKOH / g or more and 1300 mgKOH / g or less. A urethane resin composition comprising a trifunctional or higher functional polyol compound having a molecular weight of 400 or less.
(Polyol component)
The polyol component in the present embodiment is a component composed of a compound (polyol) having three or more alcoholic hydroxyl groups. Examples of the polyol include aliphatic polyols, alicyclic polyols, polyether polyols, polycarbonate polyols, polyester polyols, polycaprolactone polyols, and acrylic resin polyols.

  The polyol component in the present embodiment includes a polyol compound having a hydroxyl value of 600 mgKOH / g or more and 1300 mgKOH / g or less and a molecular weight of 400 or less. The polyol compound is preferably a compound obtained by adding propylene oxide, ethylene oxide or caprolactone to trimethylolpropane or propane-1,2,3-triol, and 1 to 2 mol of propylene oxide is added to 1 mol of trimethylolpropane. More preferably, it is a compound. By selecting such a hydroxyl equivalent and molecular weight polyol, a hardened body having a high glass transition temperature can be obtained. In particular, a derivative obtained by adding 1 to 2 moles of propylene or ethylene oxide to 1 mole of trimethylolpropane which is a solid property is in a liquid state. Further, when propylene oxide is used, ethylene oxide is caused by steric hindrance of the methyl group. It is possible and preferable because the glass transition temperature of the cured product can be increased.

  These may be used alone, but are preferably used in combination with other polyols in order to adjust the crosslinking density and viscosity. In that case, the polyol compound having a hydroxyl value of 600 mgKOH / g or more and 1300 mgKOH / g or less and a molecular weight of 400 or less is preferably 80% by mass or more based on the total amount of the polyol component. By setting it in such a range, even when several kinds of polyols are used in combination, a uniform cured body can be obtained, and problems such as generation of bubbles presumed to be caused by uncured components can be reduced.

The polyol component may contain a hydroxyl group residual prepolymer. By including the hydroxyl group residual prepolymer in the polyol component, the compatibility between the polyol component and the polyisocyanate component can be improved. The hydroxyl group-remaining prepolymer includes the polyol and a polyisocyanate described later (preferably a polyisocyanate having an alicyclic group described later) such that the hydroxyl group in the polyol is excessive with respect to the isocyanate group in the polyisocyanate. It is obtained by reacting. When the hydroxyl group equivalent in the polyol is X and the ratio when the isocyanate group equivalent in the polyisocyanate is Y is X / Y, the hydroxyl group-retaining prepolymer has a polyol and a poly It is preferably obtained by mixing and reacting with isocyanate. When X / Y takes a value of 3 or more, an increase in the molecular weight of the hydroxyl group-retaining prepolymer can be suppressed, and the viscosity can be easily handled. When X / Y takes a value of 20 or less, the effect of the prepolymer tends to be obtained effectively. The synthesis of the hydroxyl group-retaining prepolymer can be shortened by adding a catalyst, but it is preferable to carry out a reaction at room temperature or without heating in order to avoid coloring the polymer.
(Polyisocyanate component)
The polyisocyanate component in the present embodiment is a component composed of a compound having two or more isocyanate groups (polyisocyanate). The polyisocyanate is preferably an aliphatic or alicyclic polyisocyanate, has an alicyclic group and two or three isocyanate groups, and at least one isocyanate group is a secondary carbon constituting the alicyclic group. A bonded alicyclic polyisocyanate compound is more preferred. Specific examples thereof include isophorone diisocyanate, 4,4′-methylenebis- (cyclohexyl isocyanate), 1,3-bis- (isocyanatomethyl) cyclohexane, or norbornene diisocyanate (2,5- (2,6) -bis- Isocyanatomethyl [2,2,1] heptane) and the like.

  Further, an isocyanurate type, biuret type, or adduct type polyisocyanate using polyisocyanate as a raw material may be used, and isocyanurate type polyisocyanate using hexamethylene diisocyanate or isophorone diisocyanate as a raw material is particularly preferable. By using such polyisocyanate, the glass transition temperature of the obtained cured product can be improved. The ratio of the polyisocyanate having an alicyclic group to the whole polyisocyanate component is more preferably 30% by mass or more. As a result, the high temperature and high humidity resistance of the cured body can be further improved.

The polyisocyanate component preferably contains an isocyanate group residual prepolymer. By including the isocyanate group residual prepolymer in the polyisocyanate component, the compatibility between the polyol component and the polyisocyanate component can be improved. The isocyanate group-remaining prepolymer contains the polyisocyanate (preferably the polyisocyanate having the alicyclic group) and the polyol so that the isocyanate group in the polyisocyanate is excessive with respect to the hydroxyl group in the polyol. It is obtained by reacting. The isocyanate group residual prepolymer is preferably obtained by mixing and reacting a polyol and a polyisocyanate so that the above-mentioned X / Y is 0.05 to 0.3. When X / Y takes a value of 0.05 or more, the effect of the prepolymer tends to be obtained effectively. When X / Y takes a value of 0.3 or less, an increase in the molecular weight of the isocyanate group-remaining prepolymer can be suppressed, and the viscosity can be easily maintained. The synthesis of the isocyanate group-remaining prepolymer can be shortened by adding a catalyst. However, in order to avoid coloration of the polymer, it is preferable to carry out the reaction at room temperature or without heating.
(Release agent)
The liquid A and / or liquid B in the present embodiment is a saturated fatty acid represented by the following general formula (1) as a release agent, or the saturated fatty acid and a silicone-caprolactone block represented by the following general formula (2) It is preferable to further contain a copolymer.

In the formula, R ¹ represents a linear or branched hydrocarbon group having 7 to 28 carbon atoms.

In formula, m and n show the positive integer with which m / n satisfy | fills 0.5-1.0. R ² and R ³ each independently represent a divalent hydrocarbon group or a polyether chain.

Examples of the saturated fatty acid include caprylic acid, pelargonic acid, lauric acid, mythyric acid, pentadecylic acid, palmitic acid, margaric acid, stearic acid, isostearic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, montanic acid, etc. It is done. In general formula (1), the carbon number of R ¹ is usually 7 to 28, preferably 10 to 22, and more preferably 14 to 18. Among these, isostearic acid having 17 carbon atoms is particularly preferable because it is liquid and can adjust the viscosity of the urethane resin composition.

  In the saturated fatty acid, m / n in the formula preferably satisfies 0.5 to 1.0. When the ratio of m / n is 0.5 or more, compatibility with other materials is high, and problems such as white turbidity in the cured product can be suppressed. Moreover, when the ratio of m / n is 1.0 or less, excellent releasability from the molding die can be obtained. The silicone-caprolactone block copolymer preferably has a weight average molecular weight of 16000 or less from the viewpoint of excellent solubility.

  By including the saturated fatty acid and the silicone-caprolactone block copolymer in the urethane resin composition, when the urethane resin composition is molded to obtain a cured product, the releasability from the molding die is improved. Can do.

The content of the release agent is preferably 0.01 to 5.0% by mass with respect to the total amount of the polyol component and the polyisocyanate component. When the content of the release agent is 0.01% by mass or more, there is a tendency to be excellent in releasability from the molding die, and when it is 5.0% by mass or less, the heat resistance such as the glass transition temperature of the cured product is high. It tends to suppress the decrease. In addition, the saturated fatty acid and the silicone-caprolactone block copolymer are preferably used in combination. From the viewpoint of solubility, the saturated fatty acid and the silicone-caprolactone block copolymer are preferably added to the B liquid side of the isocyanate component.
(Adhesiveness imparting agent)
In order to obtain adhesion of the lead frame to silver plating or palladium plating, it is preferable to add a compound having a thiol group as an adhesion promoter. As the compound having a thiol group, a thiol group-containing silane coupling agent such as γ-mercaptopropyltrimethoxysilane or a compound having two or more thiol groups (hereinafter referred to as polythiol) is preferable. Compound bonded to primary carbon, compound bonded to secondary carbon with thiol group, one or more thiol groups bonded to primary carbon, and one or more thiol groups bonded to secondary carbon And the like.

  Examples of the compound in which the thiol group is bonded to the primary carbon include thiol groups such as tris-[(3-mercaptopropionyloxy) -ethyl] -isocyanurate, trimethylolpropane tris- (3-mercaptopropionate), etc. A compound having four thiol groups such as pentaerythritol tetrakis-3-mercaptopropionate; a compound having six thiol groups such as dipentaerythritol hexa-3-mercaptopropionate, etc. .

  In addition, as a compound in which the thiol group is bonded to the secondary carbon, a compound having two thiol groups such as 1,4-bis- (3-mercaptobutyloxy) butane; 1,3,5-tris- Compound having three thiol groups such as (3-mercaptobutyloxyethyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione; pentaerythritol tetrakis-3-mercaptobutyrate And compounds having four thiol groups such as

  It is preferable that content of a thiol compound is 0.01-2.0 mass% with respect to whole quantity of the said polyol component and the said isocyanate component. When the content of the thiol compound is 0.01% by mass or more, there is a tendency to improve the adhesion with the silver plating, and when it is 2.0% by mass or less, the heat resistance such as the glass transition temperature of the cured product. Tend to be able to hold. Moreover, when the above-mentioned mold release agent is included in the urethane resin composition, the adhesion between the cured product and the silver plating can be improved without impairing the mold release property with the molding die.

Since the thiol compound reacts with the isocyanate component, it is preferably added to the A component side of the polyol component.
(Inorganic filler)
The liquid A or the liquid B according to this embodiment may further include an inorganic filler. The inorganic filler is preferably silica in order to maintain the light transmittance of the cured product, and it is preferable to use a mixture of silica powders having different particle diameters in order to densely fill the urethane resin composition. By including an inorganic filler in the urethane resin composition, the thermal expansion coefficient of the cured body can be brought close to the thermal expansion coefficient of the lead frame of the optical semiconductor device. It becomes difficult to occur.
(Other materials)
The A liquid or the B liquid according to this embodiment may contain an antioxidant, a light stabilizer, an ultraviolet absorber, an organic filler, a polymerization inhibitor, a curing catalyst, a coupling agent, and the like in addition to the above. Further, from the viewpoint of moldability, a plasticizer, an antistatic agent, a flame retardant, and the like may be included.

  Examples of the antioxidant include hindered phenol-based, sulfur-based and phosphorus-based antioxidants. Among these, it is particularly preferable to use one or more hindered phenolic and sulfur antioxidants alone or in combination. Specifically, [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyl} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [ 5,5] undecane and the like. It is preferable that content of antioxidant is 0.05-5 mass% with respect to the whole quantity of a polyol component and a polyisocyanate component, and it is more preferable that it is 0.05-0.3 mass%. When the content of the antioxidant is 0.05% by mass or more, the effect as an antioxidant tends to be effectively obtained. There is a tendency that problems such as precipitation on the surface are less likely to occur.

  Curing catalysts include organometallics such as zinc, zirconium or aluminum, tins such as dibutyltin laurate, DBU (1,8-diazabicyclo [5,4,0] undecan-7-ene) phenol salts, octyl Catalysts such as acid salts, amines, and imidazoles can be used. Among these, zinc stearate is preferable because it is excellent in heat resistant colorability and viscosity stability at room temperature of the urethane resin composition. The content of the curing catalyst is preferably 0.001 to 1% by mass and more preferably 0.002 to 0.1% by mass with respect to the total amount of the urethane resin composition. When the content of the curing catalyst is 0.001% by mass or more, an effect of promoting the curing tends to appear, and when it is 1% by mass or less, the cloudiness of the cured product tends to be suppressed. By adding a curing catalyst, the curability of the urethane resin composition can be increased.

Examples of the coupling agent include silane coupling agents having an epoxy group, a ureido group, and the like. It is preferable that content of the coupling agent in a urethane resin composition is 0.1-2 mass% with respect to the whole quantity of a polyol component and a polyisocyanate component. By including the coupling agent in the urethane resin composition, the adhesion between the cured body and the lead frame silver plating, light emitting element, wire, inorganic filler and the like is improved.
(Hardened body)
The cured body according to the present embodiment can be produced by mixing the liquid A containing the polyol component and the liquid B containing the polyisocyanate component, and heating and reacting them. The mixing ratio of the polyol component and the polyisocyanate component, and the mixing ratio of the hydroxyl group remaining prepolymer and the isocyanate group remaining prepolymer are (total hydroxyl group equivalent of polyol and hydroxyl group remaining prepolymer) / (poly The total isocyanate group equivalent amount of isocyanate and isocyanate group remaining prepolymer) is preferably 0.7 to 1.3, more preferably 0.8 to 1.1. When the mixing ratio is in the range of 0.7 to 1.3, the cured body tends to improve heat resistance, optical characteristics, and mechanical characteristics. An inorganic filler may be added to a urethane resin composition, after mixing A liquid and B liquid.
(Optical semiconductor device)
The optical semiconductor device can be manufactured by sealing the optical semiconductor element by liquid transfer molding or compression molding the urethane resin composition obtained as described above. In this case, the urethane resin composition preferably has a gelation time at 165 ° C. of 25 to 200 seconds. By setting the gelation time within this range, it is possible to manufacture under almost the same molding conditions as in the conventional solid transfer molding. When the gelation time is shorter than 25 seconds, the molten urethane resin composition is cured before sufficiently filling the flow path in the molding die (hereinafter simply referred to as “mold”), and becomes a molded product of the cured body. Unfilled sites and voids tend to occur. On the other hand, when the gelation time is longer than 200 seconds, the molded product tends to be insufficiently cured.

  FIG. 1 is a cross-sectional view schematically showing one embodiment of an optical semiconductor device. An optical semiconductor device 200 shown in FIG. 1 includes a pair of lead frames 102 (102a and 102b), an adhesive member 103 provided on one lead frame 102a, and an optical semiconductor element 104 provided on the adhesive member 103. A wire 105 that electrically connects the optical semiconductor element 104 and the other lead frame 102b, and a part of the pair of lead frames 102, an adhesive member 103, an optical semiconductor element 104, and a sealing member 106 that seals the wire 105 And have. The optical semiconductor device 200 is called a surface mount type.

  The lead frame 102 includes one lead frame 102a and the other lead frame 102b. The lead frame 102 is a member made of a conductive material such as metal, and the surface thereof is usually covered with silver plating. Also, one lead frame 102a and the other lead frame 102b are separated from each other. The adhesive member 103 is a member for bonding and fixing one lead frame 102a and the optical semiconductor element 104 to each other and electrically connecting them. The adhesive member 103 is formed from, for example, a silver paste.

  Examples of the optical semiconductor element 104 include a light emitting diode element that emits light when a voltage is applied in the forward direction. The wire 105 is a conductive wire such as a thin metal wire that can electrically connect the optical semiconductor element 104 and the other lead frame 102b.

  The sealing member 106 is formed of a cured body of the urethane resin composition. Since the sealing member 106 protects the optical semiconductor element 104 from the outside air and plays a role of taking out light emitted from the optical semiconductor element 104 to the outside, it has high light transmittance. In the present embodiment, the sealing member 106 collects light emitted from the optical semiconductor element 104 by the lens portion 106b having a convex lens shape.

  The optical semiconductor device 200 of the present embodiment described above can employ liquid transfer molding or compression molding as part of its manufacturing process, thereby shortening the molding time and improving productivity. . Further, by adopting liquid transfer molding or compression molding, an effect of providing a lens shape that improves the light extraction efficiency as shown in FIG. 1 can be obtained.

  The optical semiconductor device 200 only needs to include an optical semiconductor element and a sealing member that seals the optical semiconductor element, and may be a shell type instead of the surface mount type as described above.

  Next, a preferred embodiment of a method for manufacturing an optical semiconductor device will be described taking as an example the case of manufacturing the optical semiconductor device 200 of FIG. The manufacturing method of the optical semiconductor device 200 according to the present embodiment includes a step of forming the sealing member 106 of the optical semiconductor device 200 by curing the urethane resin composition by liquid transfer molding or compression molding.

  The assembly component includes a pair of lead frames 102 (102a and 102b), an adhesive member 103 provided on one of the lead frames 102a, an optical semiconductor element 104 formed on the adhesive member 103, and an optical semiconductor element 104. And a wire 105 that electrically connects the other lead frame 102b. First, this structure is installed at a predetermined position in a cavity formed by a mold provided in the molding apparatus. The molding apparatus is not particularly limited as long as it is used for liquid transfer molding or compression molding, and the cavity formed by the mold has the shape of the target cured body.

  Next, the urethane resin composition is prepared, filled in a pot of a molding apparatus, a plunger is started, and the urethane resin composition is passed from the pot through a flow path such as a runner or a gate. And press-fitted into the cavity of the mold heated to a predetermined temperature. The mold is usually composed of a separable upper mold and a lower mold, and a cavity is formed by connecting them. Then, the urethane resin composition filled in the cavity is cured on the structure by holding the urethane resin composition in the cavity for a certain period of time. As a result, the cured body of the urethane resin composition is molded into a target shape, and seals a plurality of assembly parts and adheres closely to the structure.

  The mold temperature is preferably set to such a temperature that the fluidity of the urethane resin composition is high in the flow path, and the urethane resin composition can be cured in a short time in the cavity. Although this temperature is dependent also on the composition of the said urethane resin composition, it is suitable that it is 120-200 degreeC, for example. Moreover, it is preferable to set the pressure at which the urethane resin composition is press-fitted into the cavity so that the urethane resin composition can be filled in the entire cavity without any gap, specifically, 2 MPa or more. It is preferable. When the spray pressure is 2 MPa or more, unfilled portions in the cavity and voids in the sealing member 106 tend not to be generated.

  In order to make it easy to take out the cured body of the urethane resin composition (sealing member 106) from the mold, a release agent may be applied or sprayed onto the inner wall surface of the mold forming the cavity. Furthermore, in order to suppress generation | occurrence | production of the void in a hardening body, you may use the well-known reduced pressure molding apparatus which can pressure-reduce the inside of a cavity.

  Subsequently, after the structure and the cured body of the urethane resin composition adhered thereto are taken out of the cavity, the lead frame is cut so as to separate the plurality of assembly parts individually. Thus, an optical semiconductor device provided with the cured body of the urethane resin composition as a sealing member for sealing the assembly component is obtained.

  According to the manufacturing method of the optical semiconductor device of this embodiment described above, since the liquid transfer molding method or the compression molding method is adopted, the curing time can be set short, and the productivity of the optical semiconductor device is improved. Moreover, it becomes possible to give arbitrary shapes to a hardening body by using the said shaping | molding method.

  When an optical semiconductor device is produced by a casting method or a potting method using the urethane resin composition of the present embodiment, it varies depending on the type, combination, and amount of each component, but is 1 to 10 at 60 to 150 ° C. It is preferable to heat and cure for about an hour, and in particular, it is preferable to be about 1 to 10 hours at 80 to 150 ° C. Moreover, in order to reduce the internal stress generated by the rapid curing reaction, it is preferable to raise the curing temperature stepwise.

  The cured product of the urethane resin composition according to the present embodiment described above has high light transmittance, excellent optical characteristics such as heat resistance and light-resistant coloring, and mechanical characteristics. Light emitting diode (LED), phototransistor, photodiode, solid It is suitable as a sealing member for use in an optical semiconductor element such as an imaging element. In addition, by using the urethane resin composition of the present embodiment, it is possible to efficiently perform sealing of an optical semiconductor element that is uniform and has few defects such as bubbles by liquid transfer molding, and an optical semiconductor device such as an LED package can be obtained. It becomes possible to manufacture with high productivity.

EXAMPLES Hereinafter, although an Example demonstrates this invention in more detail, this invention is not limited to these at all. The blending ratio is expressed in parts by weight unless otherwise specified.
Example 1
As a polyol component, 1 mol of propylene oxide was added to 1 mol of trimethylolpropane (A2: manufactured by Perstorp, molecular weight: 134, hydroxyl value: 1260 mgKOH / g), a polyol having a molecular weight of 192 and a hydroxyl value of 880 mgKOH / g ( A4) 64.05 parts by weight were prepared to obtain a polyol component A liquid. On the other hand, isophorone diisocyanate (C1: Degussa, trade name: VESTANAT IPDI) 111.00 parts by weight, hindered phenolic antioxidant, [2- {3- (3-tert-butyl-4-hydroxy-5 -Methylphenyl) propionyl} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane (G: manufactured by Sumitomo Chemical Co., Ltd., trade name: Sumilyzer GA-80) 0 .18 parts by weight were mixed to obtain a liquid B containing an isocyanate component. The A liquid 64.05 parts by weight and the B liquid 111.18 parts by weight were mixed and stirred at room temperature until uniform, to obtain a urethane resin composition.
(Example 2)
As a polyol component, 1 mol of propylene oxide is added to 1 mol of trimethylolpropane (A2) to prepare 51.24 parts by weight of a polyol (A4) having a molecular weight of 192 and a hydroxyl value of 880 mgKOH / g, and a polyol component A liquid Got. On the other hand, 8.93 parts by weight of trimethylolpropane (A2) and 111.00 parts by weight of isophorone diisocyanate (C1) were mixed, and heated and stirred at 80 ° C. for 10 hours in a nitrogen atmosphere to give the residual isocyanate group prepolymer (B1). Obtained. Further, as a hindered phenolic antioxidant, [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyl} -1,1-dimethylethyl] -2,4,8, 0.17 part by weight of 10-tetraoxaspiro [5,5] undecane (G) was mixed to obtain a liquid B containing an isocyanate component. The above A liquid 51.24 parts by weight and B liquid 120.10 parts by weight were mixed and stirred at room temperature until uniform, to obtain a urethane resin composition.
(Example 3)
As a polyol component, 1 mol of propylene oxide is added to 1 mol of trimethylolpropane (A2) to produce 61.81 parts by weight of a polyol (A4) having a molecular weight of 192 and a hydroxyl value of 880 mgKOH / g, and further imparting adhesiveness. 1.06 parts by weight of γ-mercaptopropyltrimethoxysilane (D: Shin-Etsu Chemical Co., Ltd., trade name: KBM-803) was added as an agent and stirred until uniform to obtain a polyol component A solution.

On the other hand, 1.56 parts by weight of trimethylolpropane (A2) and 22.93 parts by weight of 4,4′-methylenebis- (cyclohexyl isocyanate) (C2: manufactured by Degussa, trade name: H ₁₂ MDI) were mixed, and nitrogen was mixed. The mixture was heated and stirred at 80 ° C. for 10 hours in an atmosphere to obtain an isocyanate group residual prepolymer (B2).

As the polyisocyanate component, 24.49 parts by weight of the above-mentioned isocyanate group residual prepolymer (B2), 4,4′-methylenebis- (cyclohexyl isocyanate) (C2) 22.93 parts by weight, norbornene diisocyanate (C3: Mitsui Takeda Chemical Co., Ltd.) Product name: Cosmonate NBDI) 41.8 parts by weight, 75 mass% butyl acetate solution of isocyanurate type polyisocyanate which is a trimer of isophorone diisocyanate (C4: manufactured by Degussa, product name: Vestanat T1890ME) 00 parts by weight, and [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyl} -1,1-dimethylethyl] -2,4 as a hindered phenolic antioxidant , 8,10-Tetraoxaspir [5,5] were mixed undecane (G) 0.21 parts by weight, butyl acetate was heated desolvation under reduced pressure. On the other hand, 5.33 parts by weight of isostearic acid (F1: made by Higher Alcohol Industry Co., Ltd., trade name: isostearic acid EX) and 1.07 parts by weight of a silicone-caprolactone block copolymer (F2) as a release agent are used as a polyisocyanate component. And heated and mixed at 80 ° C. for 2 hours. The silicone-caprolactone block copolymer (F2) was prepared by adding 22 mol of caprolactone to 1 mol of both-end polyether-modified silicone (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: X-22-4952). In (2), m / n = 0.6 and the weight average molecular weight Mw = 4,000. Then, after cooling to room temperature, 0.11 part by weight of zinc stearate (E: manufactured by NOF Corporation, trade name: MZ-2) is added as a curing catalyst, and the mixture is stirred until it is uniform, and a B liquid containing an isocyanate component Was prepared. The above A liquid 62.87 parts by weight and B liquid 157.44 parts by weight were stirred at room temperature until uniform, to obtain a urethane resin composition.
Example 4
As a polyol component, instead of the polyol (A4) of Example 3, 1 mol of ethylene oxide is added to 1 mol of trimethylolpropane (A2), and the polyol (A5) 57. has a molecular weight of 179 and a hydroxyl value of 940 mgKOH / g. A urethane resin composition was obtained in the same manner as in Example 3 except that 73 parts by weight was prepared and (A5) was used.
(Example 5)
As the polyisocyanate component, the urethane resin composition was the same as in Example 3 except that the release agent of Example 3 was 8.53 parts by weight of isostearic acid (F1) and the silicone-caprolactone block copolymer (F2) was removed. I got a thing.
(Example 6)
As a polyol component, instead of the polyol (A4) of Example 3, 55.40 parts by weight of the polyol (A4), a polycaprolactone triol having a molecular weight of 300 and a hydroxyl value of 540 mgKOH / g (A3: manufactured by Daicel Chemical Industries, Ltd.) , Trade name: Plaxel 303, molecular weight: 313, hydroxyl value: 540 mg KOH / g) 10.43 parts by weight of a urethane resin composition was obtained in the same manner as in Example 3 except that it was stirred until uniform. It was.
(Comparative Example 1)
As the polyol component, propane-1,2,3-triol (A1: manufactured by Sakamoto Yakuhin Kogyo Co., Ltd., trade name: purified glycerin, molecular weight: 92, hydroxyl value: 1830 mgKOH / g), 30.64 parts by weight, and polycaprolactone triol (A3) A urethane resin composition was obtained in the same manner as in Example 1 except that 62.57 parts by weight were stirred until uniform.
(Comparative Example 2)
Except that 29.92 parts by weight of trimethylolpropane (A2) and 31.28 parts by weight of polycaprolactone triol (A3) were heated and stirred at 80 ° C. for 2 hours as a polyol component, and a uniform polyol component was used. A urethane resin composition was obtained in the same manner as in Example 3.
(Comparative Example 3)
Example except that 5.06 parts by weight of propane-1,2,3-triol (A1) and 83.42 parts by weight of polycaprolactone triol (A3) were stirred and used as the polyol component until uniform. In the same manner as in 3, a urethane resin composition was obtained.

  The amount of each material used in Examples 1 to 6 and Comparative Examples 1 to 3 is shown in Table 1 below.

The urethane resin composition obtained as described above was evaluated according to the following method.
<Fabrication of optical semiconductor package>
The urethane resin compositions obtained in Examples 1 and 2 and Comparative Example 1 were filled into the cavities of a ceramic surface-mounted package with a light-emitting element mounted having an outer shape of 5 mm × 5 mm × 1 mm and a cavity diameter of 4 mm by a potting method. Then, heating and curing were performed at 100 ° C. for 1 hour, 125 ° C. for 1 hour, and 150 ° C. for 4 hours to produce an optical semiconductor device. Further, the urethane resin compositions obtained in Examples 3 to 6 and Comparative Examples 2 to 3 were used with a liquid transfer molding machine, a mold temperature of 165 ° C., a spray pressure of 9.8 MPa, an injection time of 30 seconds, and a curing time of 120. Molded as seconds, and further post-cured in an oven at 150 ° C. for 4 hours to produce an optical semiconductor package as shown in FIG. The sealing part of the produced optical semiconductor package was observed with a microscope, and the uniformity of the cured part, that is, the presence or absence of fluctuations or bubbles was examined. The results are shown in Table 2.
<Measurement of hardness and glass transition temperature>
The hardness of the cured product of the urethane resin composition was measured by Shore hardness D, and the glass transition temperature was measured by a thermomechanical analyzer. The results are shown in Table 2.

  In Table 2, the uniformity of the cured product, A is uniform, and B is a fluctuation in transparency. Bubbles in the cured body, A indicates no bubbles, and B indicates that bubbles were observed.

  In each of Examples 1 to 6, a hardened body having a glass transition temperature of 120 ° C. or higher was obtained, the transparency of the cured body was uniform, and defects such as bubbles were not observed. On the other hand, in Comparative Example 1, sufficient compatibility between the liquid A and the liquid B was not obtained, and a uniform cured body could not be obtained. In Comparative Examples 2 and 3, a hardened body having a glass transition temperature of 83 to 84 ° C. was obtained, but fluctuations and bubbles were observed in the cured body.

  The cured body of the present invention is hard and has a high glass transition temperature, excellent uniformity in transparency, and can exhibit excellent performance as a cured body used for sealing an optical semiconductor.

DESCRIPTION OF SYMBOLS 102,102a, 102b ... Lead frame, 103 ... Adhesive member, 104 ... Optical semiconductor element, 105 ... Wire, 106 ... Sealing member, 106a ... Flat plate part, 106b ... Lens part, 200 ... Optical semiconductor device.

Claims (10)

A liquid containing a polyol component;
B liquid containing a polyisocyanate component;
A urethane resin composition comprising:
The polyol component is
A trifunctional or higher functional polyol compound having a hydroxyl value of 600 mgKOH / g or more and 1300 mgKOH / g or less and a molecular weight of 400 or less,
Urethane resin composition.   The polyisocyanate component has an alicyclic group and two or three isocyanate groups, and at least one isocyanate group is bonded to a secondary carbon constituting the alicyclic group. The urethane resin composition according to claim 1, comprising 30% by mass or more of the compound.   The urethane resin composition according to claim 1 or 2, wherein the polyol compound is a compound obtained by adding propylene oxide, ethylene oxide or caprolactone to trimethylolpropane or propane-1,2,3-triol.   The urethane resin composition according to claim 3, wherein the polyol compound is a compound obtained by adding 1 to 2 moles of propylene oxide to 1 mole of trimethylolpropane.   The urethane resin composition according to any one of claims 1 to 4, wherein a content of the polyol compound is 80% by mass or more based on a total amount of the polyol component. The liquid A or the liquid B is
Or a saturated fatty acid represented by the following general formula (1):
The saturated fatty acid and a silicone-caprolactone block polymer having a weight average molecular weight of 16000 or less represented by the following general formula (2):
The urethane resin composition as described in any one of Claims 1-5.

(In the formula, R ¹ represents a linear or branched saturated hydrocarbon group having 7 to 28 carbon atoms.)

(In the formula, m and n are positive integers satisfying m / n of 0.5 to 1.0. R ² and R ³ each independently represents a divalent hydrocarbon group or a polyether chain. Show.) A liquid containing a polyol component containing a trifunctional or higher polyol compound having a hydroxyl value of 600 mgKOH / g or more and 1300 mgKOH / g or less and a molecular weight of 400 or less;
B liquid containing a polyisocyanate component;
Hardened | cured material obtained by hardening | curing the urethane resin composition which consists of this by mixing A liquid and B liquid. The liquid A or the liquid B is
Or a saturated fatty acid represented by the following general formula (1):
The saturated fatty acid and a silicone-caprolactone block polymer having a weight average molecular weight of 16000 or less represented by the following general formula (2):
The cured body according to claim 7.

(In the formula, R ¹ represents a linear or branched saturated hydrocarbon group having 7 to 28 carbon atoms.)

(In the formula, m and n are positive integers satisfying m / n of 0.5 to 1.0. R ² and R ³ each independently represents a divalent hydrocarbon group or a polyether chain. Show.)   The hardened | cured material of Claim 7 or 8 in which the said A liquid and / or the said B liquid further contain an inorganic filler.   An optical semiconductor device provided with the sealing member which consists of a hardening body as described in any one of Claims 7-9.

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