TW202031772A - Hygroscopic silicone resin composition, transparent sealing material for organic EL, transparent drying material for organic EL and methods of using thereof - Google Patents

Abstract

The invention provides a hygroscopic silicone resin composition, a transparent sealing material for organic EL, a transparent drying material for the organic EL and methods of using thereof. The hygroscopic silicone resin composition comprises silicone, and surface treatment hygroscopic silicon dioxide particles with a coating part which is obtained through combining the silicone compound and the condensate thereof, wherein the hygroscopic capacity is 1.0*10<SP>-7</SP>g/mm3, wherein the refractive index of the silicone resin and the refractive index of the silicon dioxide particles are respectively1.39-1.42. Relative to total content of the silicone resin composition, the content of the silicon dioxide particles is 1-70mass%. The silicone silicone is a trifunctional silane compound, silazane compound or one-functional silane compound which is represented by a specific formula.

Description

Hygroscopic silicone resin composition, transparent sealing material for organic EL, transparent drying material for organic EL, and methods of use

The present invention relates to a hygroscopic silicone resin composition, a transparent sealing material for organic EL (Electronics luminescence), a transparent drying material for organic EL, and a method of use thereof.

Organic electronic light-emitting (hereinafter referred to as organic EL) panels are called automatic light-emitting type and the element itself emits light, so there is no need for other light sources like the backlight of liquid crystal panels, so it has low power consumption and is easy to thin and lighten Such features are considered to be of high image quality compared to LCD panels. However, only a small amount of moisture penetrates into the panel, which causes the problem of damage to the light-emitting area of the device (the generation of dark spots).

The organic EL panel must have a structure that can prevent the penetration of high levels of moisture. Therefore, a structure in which the organic EL element is sealed with a transparent substrate made of glass or the like is generally used. This structure is to form an organic EL element with an anode, an organic layer, and a cathode layered on a substrate such as glass, and a hollow sealing structure such as opposing excavation glass is formed, and the inside is filled with dried nitrogen (N ₂ ) It is obtained by filling with gas, etc., and adhering the end with a sealing material. At this time, various studies such as a method of installing a desiccant inside the organic EL panel or a method of covering the organic EL element with a filler have been reported for the purpose of removing the moisture that has penetrated into the organic EL panel. In either method, when the desiccant or the filling material has translucency, the light generated by the organic EL element is taken out from the top to the outside, and the so-called top emission is possible, so it is more effective.

In addition, although organic EL elements are mainly formed in processes such as vapor deposition, due to the presence of fine particles, a so-called short phenomenon occurs in which the cathode and the anode are short-circuited. In addition, when moisture-absorbing particles are mixed with a sealing material such as resin, a short-circuit phenomenon (Short phenomenon) may occur even by aggregation of the moisture-absorbing particles. When such a short phenomenon occurs, it is necessary to separate the surrounding elements of the particles or aggregates of the moisture-absorbing particles that are the cause by lasers or the like, which causes the problem of loss of light-emitting parts or increase of steps.

In addition, organic EL panels are required to be thinned. In addition to thin panels, thin panels with curved shapes are also attracting attention. For such a thin panel, resistance to bending is sometimes required, not only for thinness, but also for flexibility.

In addition, attention has also been paid to organic EL panels having a flexible structure that can be bent, and thinness and flexibility are similarly required for each constituent member such as a translucent substrate, a desiccant, and a filler.

Patent Document 1 has disclosed that a desiccant such as zeolite and silica gel is added to a silicone resin and filled in an organic EL panel. In this method, when a desiccant is added in an amount necessary to suppress the loss of the light-emitting area of the organic EL light-emitting element due to moisture, the light transmittance cannot be obtained. The applicability of top emission) becomes impossible.

In addition, Patent Document 2 discloses that an organometallic compound is mixed with a silicone resin as a water-trapping component and filled in an organic EL panel. In this method, since the viscosity of the organometallic compound is high, it is expected that the viscosity can be lowered by mixing with the upper silicone resin during processing, but there is a problem that the higher the ratio of the silicone resin, the less light transmittance can be obtained. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] JP 2017-183191 A [Patent Document 2] JP 2013-176751 A

[Problem Solved by Invention]

In view of the above-mentioned matters, the present invention makes it possible to provide high-transparency top emission. It can also suppress the growth of shrinkage and the loss of the light-emitting part (dark spots) of the device under high transparency, high temperature and high humidity, and has The purpose is a transparent sealing material for organic EL that suppresses the effect of a short phenomenon, and a hygroscopic silicone resin composition provided with a transparent desiccant for organic EL. [Means to solve the problem]

The inventors of the present invention conducted detailed reviews to achieve the above-mentioned objects and found that a composition made of silicone resin with a specific refractive index and surface-treated hygroscopic silica particles and exhibiting hygroscopicity is used as an organic EL When a transparent sealing material or desiccant is used, top emission is possible, the growth of shrinkage under high transparency, high temperature and high humidity is suppressed, the generation of dark spots and the generation of short circuits can be suppressed, and the present invention is completed By.

(但，R¹ 為取代或非取代之碳原子數1～6的一價烴基，R⁴ 為相同或相異種的碳原子數1～6之一價烴基)；

(但，R² 為相同或相異種的取代或非取代之碳原子數1～6的一價烴基)；

(但，R² 與上述相同，X為OH基或水解性基)。 2.上述二氧化矽微粒子為溶膠凝膠二氧化矽微粒子之上述1記載的吸濕性矽氧樹脂組成物。 3.上述表面處理吸濕性二氧化矽微粒子在體積基準粒度分布中之中間徑為0.01～0.5μm之上述1或2記載的吸濕性矽氧樹脂組成物。 4.上述矽氧樹脂為含有下述(A)～(C)成分的上述1～3中任一所記載的吸濕性矽氧樹脂組成物。 (A)於1分子中具有至少2個烯基之直鏈狀有機聚矽氧烷、 (B)於1分子中具有至少2個鍵結於矽原子的氫原子之有機氫聚矽氧烷：含有量為對於(A)成分中之鍵結於矽原子的烯基1莫耳而言，相當於(B)成分中之鍵結於矽原子的氫原子1.0～2.0莫耳之量、 (C)矽氫化觸媒 5.一種吸濕性矽氧樹脂組成物之製造方法，其為製造上述1～4中任一所記載的吸濕性矽氧樹脂組成物的方法，其特徵為上述表面處理吸濕性二氧化矽微粒子藉由下述步驟(A1)～(A4)而製造者； 步驟(A1)：藉由將下述式(I)所示4官能性矽烷化合物或其部分水解生成物，或此等混合物，在鹼性物質的存在下，在親水性有機溶劑與水之混合液中進行水解、縮合，得到含有SiO₂ 單位之親水性球狀二氧化矽微粒子的混合溶劑分散液之步驟；

(但，R³ 為相同或相異種的碳原子數1～6之一價烴基)、 步驟(A2)：藉由於上述親水性球狀二氧化矽微粒子之混合溶劑分散液中，添加下述式(II)所示3官能性矽烷化合物或其部分水解生成物，或此等混合物，處理上述親水性球狀二氧化矽微粒子之表面，而於上述親水性球狀二氧化矽微粒子之表面上導入R¹ SiO_3/2 單位(但，R¹ 與下述相同)，得到第一表面處理球狀二氧化矽微粒子之混合溶劑分散液的步驟；

(但，R¹ 為取代或非取代的碳原子數1～6之一價烴基，R⁴ 為相同或相異種的碳原子數1～6之一價烴基)； 步驟(A3)：藉由自上述第一表面處理球狀二氧化矽微粒子的混合溶劑分散液除去上述親水性有機溶劑與水的一部分，並濃縮後得到第一表面處理球狀二氧化矽微粒子之混合溶劑濃縮分散液的步驟； 步驟(A4)：於上述第一表面處理球狀二氧化矽微粒子的混合溶劑濃縮分散液中添加下述式(III)所示矽氮烷化合物，或下述式(IV)所示1官能性矽烷化合物或此等混合物，使上述第一表面處理球狀二氧化矽微粒子的表面進行處理而於上述第一表面處理球狀二氧化矽微粒子的表面上導入R² ₃ SiO_1/2 單位(但，R² 與下述相同)，得到第二表面處理二氧化矽微粒子的步驟；

(但，R² 為相同或相異種的取代或非取代之碳原子數1～6的一價烴基)；

(但，R² 與上述相同。X為OH基或水解性基)。 6.含有如上述1～4中任一所記載的吸濕性矽氧樹脂組成物所成的有機EL用透明密封材料。 7.含有如上述1～4中任一所記載的吸濕性矽氧樹脂組成物的硬化物之有機EL用透明乾燥劑。 8.將如上述6記載的有機EL用透明密封材料塗布於有機EL元件上，並使其硬化而使用為特徵之有機EL用透明密封材料的使用方法。 9.將如上述6記載的有機EL用透明密封材料填充於內部具有有機EL元件的面板內，並使其硬化而使用為特徴之有機EL用透明密封材料的使用方法。 10.將如上述7記載的有機EL用透明乾燥劑配置於內部具有有機EL元件之面板內而使用為特徴的有機EL用透明乾燥劑之使用方法。 [發明之效果]Therefore, the present invention provides the following hygroscopic silicone resin composition, transparent sealing material for organic EL, transparent drying material for organic EL, and methods of use thereof. 1. A hygroscopic silicone resin composition containing silicone resin, and at least a part of the surface has surface-treated hygroscopic silicon dioxide fine particles with a coating formed by bonding an organosilicon compound or the condensate A hygroscopic silicone resin composition with a moisture absorption capacity of 1.0×10 ^-7 g/mm ³ or more, characterized in that the refractive index of the silicone resin and the refractive index of the silica particles are both 1.39～1.42 The content of the silicon dioxide microparticles to the entire silicone resin composition is 1 to 70% by mass, and the organosilicon compound is a trifunctional silane compound represented by the following formula (II) and the following formula (III) It shows a silazane compound or a monofunctional silane compound represented by the following formula (IV);

(However, R ¹ is a substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms, and R ⁴ is the same or different kind of monovalent hydrocarbon group with 1 to 6 carbon atoms);

(However, R ² is the same or different substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms);

(However, R ² is the same as above, and X is an OH group or a hydrolyzable group). 2. The above-mentioned silica fine particles are the hygroscopic silicone resin composition described in 1 above of sol-gel silica fine particles. 3. The hygroscopic silicone resin composition described in 1 or 2 above in which the intermediate diameter of the surface-treated hygroscopic silica fine particles in the volume-based particle size distribution is 0.01 to 0.5 μm. 4. The silicone resin is a hygroscopic silicone resin composition as described in any one of the above 1 to 3 containing the following components (A) to (C). (A) Linear organopolysiloxane having at least two alkenyl groups in one molecule, (B) Organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms in one molecule: The content is equivalent to 1.0 to 2.0 moles of hydrogen atoms bonded to silicon atoms in component (B) for 1 mol of alkenyl groups bonded to silicon atoms in component (A), (C ) Hydrosilylation catalyst 5. A method for producing a hygroscopic silicone resin composition, which is a method for producing the hygroscopic silicone resin composition described in any one of 1 to 4, characterized by the above-mentioned surface treatment Hygroscopic silica microparticles are manufactured through the following steps (A1) to (A4); Step (A1): By hydrolyzing the tetrafunctional silane compound represented by the following formula (I) or its partial hydrolysis product , Or these mixtures, hydrolyzed and condensed in a mixture of hydrophilic organic solvents and water in the presence of alkaline substances to obtain a mixed solvent dispersion of hydrophilic spherical silica particles containing SiO ₂ units step;

(However, R ³ is a monovalent hydrocarbon group with 1 to 6 carbon atoms of the same or different species), Step (A2): Add the following formula to the mixed solvent dispersion of the hydrophilic spherical silica particles (II) The trifunctional silane compound or its partially hydrolyzed product, or a mixture thereof, is used to treat the surface of the hydrophilic spherical silica microparticles, and introduce it on the surface of the hydrophilic spherical silica microparticles R ¹ SiO _3/2 units (however, R ¹ is the same as the following) to obtain a mixed solvent dispersion of the first surface-treated spherical silica particles;

(However, R ¹ is a substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms, and R ⁴ is a monovalent hydrocarbon group with 1 to 6 carbon atoms of the same or different species); Step (A3): The step of removing a part of the hydrophilic organic solvent and water from the mixed solvent dispersion of the first surface-treated spherical silica particles, and concentrating to obtain a mixed solvent concentrated dispersion of the first surface-treated spherical silica particles; Step (A4): Add the silazane compound represented by the following formula (III) or the monofunctionality represented by the following formula (IV) to the concentrated dispersion of the mixed solvent of the first surface-treated spherical silica particles Silane compound or these mixtures, subject the surface of the first surface-treated spherical silica particles to the surface of the first surface-treated spherical silica particles to introduce R ² ₃ SiO _1/2 units (but , R ² is the same as below), the step of obtaining the second surface-treated silica particles;

(However, R ² is the same or different substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms);

(However, R ² is the same as above. X is an OH group or a hydrolyzable group). 6. A transparent sealing material for organic EL containing the hygroscopic silicone resin composition as described in any one of 1 to 4 above. 7. A transparent desiccant for organic EL containing a cured product of the hygroscopic silicone resin composition as described in any one of 1 to 4 above. 8. The method of using the transparent sealing material for organic EL characterized by applying the transparent sealing material for organic EL described in 6 above to the organic EL element and curing it. 9. The transparent sealing material for organic EL as described in 6 above is filled in a panel having organic EL elements inside, and it is cured to use the characteristic transparent sealing material for organic EL. 10. It is a special method of using the transparent desiccant for organic EL as described in 7 above to be used in a panel with organic EL elements inside. [Effects of Invention]

The transparent sealing material for organic EL obtained from the hygroscopic silicone resin composition of the present invention is capable of reducing the growth of shrinkage even under high transparency, high temperature and high humidity, and suppressing damage (darkness) of organic EL elements Point generated). Furthermore, since the transparent sealing material for organic EL of the present invention has high transparency, it can be applied to a top emission type that can emit light from an organic EL element. In addition, the method of using the transparent sealing material for organic EL and the desiccant of the present invention is to directly coat the organic EL element or arrange it in the organic EL panel. Since silicone resin is flexible, it can be applied to Flexible organic EL panel. And regarding the transparent sealing material for organic EL, desiccant and method of use of the present invention, it is capable of suppressing the following effects. The effect is that the low molecular siloxane in the sealing material diffuses and accumulates in the organic EL panel, so that It has the effect of insulating the vicinity of the fine particles during the formation of the organic EL element, and suppressing the short-circuit phenomenon (Short phenomenon) caused by the particles such as the cathode and the anode being short-circuited by the particles. In addition, according to the transparent sealing material for organic EL and the method of use of the present invention, it is possible to obtain excellent dispersibility of silica particles mixed when used as a moisture absorbing material, so it has the ability to suppress aggregation of the moisture absorbing material. The effect of the performance of short phenomenon (Short phenomenon).

[Type of Implementation of Invention]

The present invention will be described in further detail below. The hygroscopic silicone resin composition of the present invention contains silicone resin, and at least a part of the surface has hygroscopic silica fine particles with a coating formed by bonding an organosilicon compound or its condensate, which absorbs A hygroscopic silicone resin composition with a moisture capacity of 1.0×10 ^-7 g/mm ³ or more. The refractive index of the silicone resin and the refractive index of the silica particles are both 1.39～1.42. A hygroscopic silicone resin composition in which the content of silicon fine particles relative to the sealing material is 1 to 70% by mass.

[Silicone resin] The silicone resin in the present invention preferably contains the following components (A) to (C). Each component is explained in detail below. (A) Linear organopolysiloxane with at least 2 alkenyl groups in 1 molecule (B) Organohydrogen polysiloxane having at least 2 hydrogen atoms bonded to silicon atoms in a molecule: The content is for 1 mol of alkenyl groups bonded to the silicon atoms in component (A) , Equivalent to the mass of 1.0～2.0 moles of hydrogen atom bonded to silicon atom in component (B) (C) Hydrosilation catalyst

(A) Linear organopolysiloxane containing alkenyl groups The (A) component in the present invention is a linear organopolysiloxane having at least two alkenyl groups in one molecule.

所示有機聚矽氧烷。The linear organopolysiloxane containing alkenyl groups in the component (A) is a linear organopolysiloxane having at least two, preferably at least 2 to 8 alkenyl groups in one molecule. Specifically as the following formula (1)

Shown organopolysiloxane.

In the above formula (1), R ^{6 is} independently a monovalent hydrocarbon group selected from an alkyl group having 1 to 10 carbons, an aryl group having 6 to 12 carbons, and an alkenyl group having 2 to 10 carbons. Specific examples of monovalent hydrocarbon groups include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, and cyclohexyl, or vinyl, allyl, butenyl, and pentenyl groups. From the viewpoint of setting the refractive index of the silicone resin to 1.39 to 1.42, the methyl group is preferred from the viewpoint of alkenyl groups such as hexenyl groups and cyclohexenyl groups or aryl groups such as phenyl groups. The alkenyl group in the component (A) may have either at the end of the molecular chain and the side chain, but it is preferable to have the alkenyl group only at the end. x is an integer of 100-50,000, preferably an integer of 150-20,000.

Specific examples of the above-mentioned linear organopolysiloxane containing alkenyl groups include trimethylsiloxy blocked dimethylsiloxane, methylvinylsiloxane copolymers, molecular Trimethylsiloxy blocked methyl vinyl polysiloxane at both ends of the chain, trimethylsiloxy blocked dimethylsiloxane at both ends of the molecular chain, methyl vinyl siloxane, methyl phenyl silicone Oxyane copolymer, dimethyl vinyl siloxy blocked dimethyl polysiloxane at both ends of molecular chain, dimethyl vinyl siloxy blocked at both ends of molecular chain methyl vinyl polysiloxane, molecular chain Two-terminal dimethylvinylsiloxy blocked dimethylsiloxane･methylvinylsiloxane copolymer, molecular chain two-terminal dimethylvinylsiloxane blocked dimethylsiloxane･methyl Vinylsiloxane･methylphenylsiloxane copolymer, divinylmethylsiloxy block at both ends of the molecular chain, dimethylpolysiloxane, block both ends of the molecular chain with divinylmethylsiloxy Dimethylsiloxane･methylvinylsiloxane copolymer, trivinylsiloxy blocked dimethyl polysiloxane at both ends of molecular chain, trivinylsiloxy blocked dimethyl at both ends of molecular chain Silicone, methyl vinyl silicone copolymer, etc.

The linear organopolysiloxane containing alkenyl groups may be used singly or in combination of two or more kinds. When two types of linear organopolysiloxanes are used in combination, the weight average molecular weight of the organopolysiloxane on the low molecular weight side is preferably 1,000 to 50,000, and more preferably 1,500 to 20,000. On the other hand, the weight average molecular weight of the organopolysiloxane on the high molecular weight side is preferably more than 1,500 to 200,000, preferably more than 2,000 to 100,000. However, it is (weight average molecular weight on the low molecular side) <(weight average molecular weight on the high molecular side).

In addition, the weight average molecular weight in the present invention can be obtained as the weight average molecular weight in terms of polystyrene in GPC (gel permeation chromatography) analysis.

In addition, components other than the alkenyl group-containing linear organopolysiloxane as the component (A) may include alkenyl group-containing resinous organopolysiloxanes. However, from the viewpoint of suppressing the generation of bubbles and deterioration of light transmittance during curing, the content of the alkenyl group-containing resinous organopolysiloxane is preferably 1% by mass or less with respect to the component (A).

(B) Organohydrogen polysiloxane The organohydrogenpolysiloxane of component (B) in the present invention is a crosslinking agent that forms a crosslinked structure with the above-mentioned alkenyl group-containing organopolysiloxane by hydrosilation, which is An organohydrogen polysiloxane having at least two hydrogen atoms bonded to silicon atoms in one molecule.

As a specific example of the organohydrogen polysiloxane of the component (B), 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane Silicone, ginseng (hydrodimethylsiloxy) methyl silane, ginseng (hydrodimethyl siloxy) phenyl silane, methyl hydrogen siloxane, methyl hydrogen siloxane, dimethyl -Based siloxane cyclic copolymer, trimethylsiloxy blocked methyl hydrogen polysiloxane at both ends of the molecular chain, trimethylsiloxy blocked dimethylsiloxane at both ends of the molecular chain, methyl hydrogen silicon Oxyane copolymer, trimethylsiloxy blocked dimethylsiloxane at both ends of molecular chain, methylhydrosiloxane, methylphenylsiloxane copolymer, trimethylsiloxy at both ends of molecular chain Blocked dimethylsiloxane･methylhydrosiloxane･diphenylsiloxane copolymer, dimethylhydrosiloxane at both ends of the molecular chain, blocked methylhydrosiloxane at both ends of the molecular chain, dimethyl at both ends of the molecular chain Hydrogen silyloxy-blocked dimethyl polysiloxane, dimethylhydrosiloxane blocked dimethyl siloxane at both ends of the molecular chain, copolymer of methylhydrosiloxane, dimethyl hydrogen at both ends of the molecular chain Siloxy-blocked dimethylsiloxane･methylphenylsiloxane copolymer, dimethylhydrosiloxy-blocked dimethylsiloxane･diphenylsiloxane copolymer at both ends of the molecular chain, molecule The dimethylhydrosiloxy group-blocked methylphenyl polysiloxane at both ends of the chain, the dimethylhydrosiloxy group-blocked diphenylpolysiloxane at both ends of the molecular chain, or each of these exemplified compounds can be mentioned Part or all of the methyl group is substituted by other alkyl groups such as ethyl, propyl, etc., containing the siloxane unit shown in R ₃ SiO _{1/2 and the} siloxane unit shown in R ₂ HSiO _1/2 And formula: organosiloxane copolymer formed by siloxane unit shown in SiO _4/2 , containing formula: siloxane unit shown in R ₂ HSiO _1/2 and formula: siloxane unit shown in SiO _4/2 The resulting organosiloxane copolymer contains formula: siloxane unit shown in RHSiO _2/2 and formula: siloxane unit shown in RSiO _3/2 or formula: siloxane unit shown in HSiO _3/2 Organosiloxane copolymers, and mixtures containing two or more of these organopolysiloxanes.

The compounding quantity of component (B) is that, for 1 mol of alkenyl group bonded to silicon atom in component (A), it is equivalent to 1.0 to 2.0 mol of hydrogen atom bonded to silicon atom in component (B) The amount of ears is preferably an amount equivalent to 1.0 to 1.5 moles.

(C) Hydrosilation catalyst The hydrosilylation catalyst of the component (C) in the present invention is the alkenyl group-containing organopolysiloxane of the component (A) and the organohydrogenpolysiloxane of the component (B) by a hydrosilylation reaction Catalyst for cross-linking.

As the catalyst for the hydrosilation reaction, platinum group metal catalysts are preferred. Specific examples include platinum black, second platinum chloride, chloroplatinic acid, chloroplatinic acid and monohydric alcohol reactants, chlorination Complexes of platinum acid and olefins, complexes of chloroplatinic acid and vinyl-containing (poly)siloxanes, platinum-acetone acetone complexes, platinum-cyclopentadienyl complexes, etc. Platinum group metal catalyst.

In addition, as the (C) component, it is possible to use one that is inert under shading and is changed to an active platinum group metal catalyst by irradiating light with a wavelength of 200 to 500 nm. As a specific example of such a component (C), platinum group metal catalysts can be cited. Among them, compounds of platinum group elements such as ruthenium, rhodium, palladium, and platinum are also preferable, and platinum compounds are particularly preferable. As an example of the platinum compound, a platinum complex having a β-diketoplatinum complex or a cyclic diene compound or the like as a ligand can be cited. These compounds may be synthesized or sold.

As the above-mentioned β-diketone platinum complexes, for example, trimethyl(acetyldionate) platinum complexes, trimethyl(2,4-glutaric acid) platinum complexes, trimethyl (3,5-pimelic acid) platinum complex, trimethyl (methyl acetate) platinum complex, bis(2,4-glutarate) platinum complex, bis(2, 4-adipate) platinum complex, bis(2,4-pimelate) platinum complex, bis(3,5-pimelate) platinum complex, bis(1-phenyl-1, 3-succinate) platinum complex, bis(1,3-diphenyl-1,3-malonate) platinum complex, etc., preferably bis(β-diketonate) platinum complex , More preferably bis(acetodionate) platinum complex.

Examples of the platinum complexes having a cyclic diene compound in the ligand include (η ⁵ -cyclopentadienyl) dimethyl platinum complex, (η ⁵ -cyclopentadienyl) )Diphenylplatinum complex, (η ⁵ -cyclopentadienyl)dipropylplatinum complex, (2,5-bornadiene)dimethylplatinum complex, (2,5-bornyl) Diene) diphenyl platinum complex, (η ⁵ -cyclopentadienyl) dimethyl platinum complex, (η ⁵ -methylcyclopentadienyl) diethyl platinum complex, ( η ⁵ -trimethylsilylcyclopentadienyl) diphenyl platinum complex, (η ⁵ -methylcyclooctadiene) diethyl platinum complex, (η ⁵ -cyclopentadienyl) ) Trimethylplatinum complex, (η ⁵ -cyclopentadienyl) ethyl dimethyl platinum complex, (η ⁵ -cyclopentadienyl) acetyl dimethyl platinum complex, ( η ⁵ -Methylcyclopentadienyl)trimethylplatinum complex, (η ⁵ -Methylcyclopentadienyl)trihexylplatinum complex, (η ⁵ -Trimethylsilylcyclopentadiene) Alkenyl) trimethylplatinum complex, (η ⁵ -dimethylphenylsilylcyclopentadienyl) triphenylplatinum complex, and (η ⁵ -cyclopentadienyl) dimethyl Yltrimethylsilylmethylplatinum complex, etc., preferably (η ⁵ -methylcyclopentadienyl)trialkylplatinum complex, more preferably (η ⁵ -methylcyclopentadiene Base) Trimethylplatinum complex.

(C) The compounding amount of the component may be an amount that can promote the curing (hydrosilation reaction) of the resin composition of the present invention, and it is not particularly limited, but from the viewpoint of curing properties, storage stability, and cost, When the total mass of the component (A) and the component (B) is converted into the amount of platinum group metal, it is preferably 0.5 to 1,000 ppm, and preferably 1 to 500 ppm.

Other ingredients In addition to the above-mentioned components (A) to (C), the silicone resin of the present invention may contain other components within a range that does not impair the effects of the present invention. Specific examples include reaction control agents and adhesive-imparting materials for the hydrosilation reaction (especially containing at least one selected from alkenyl, epoxy, amino, (meth)acryloxy, mercapto, etc.) in the molecule Functional groups, and functional alkoxysilanes (organosilicon compounds such as functional alkoxysilanes that do not contain SiH groups in the molecule), thixotropy imparting agents, etc.

The refractive index of the silicone resin used in the present invention is in the range of 1.39 to 1.42. When the refractive index is outside this range, the difference in refractive index with the silica particles becomes larger, which impairs the transparency of the cured product obtained.

[Surface treatment hygroscopic silica particles] The surface-treated hygroscopic silica fine particles used in the present invention are hygroscopic silica fine particles having at least a part of the surface having a coating formed by bonding an organosilicon compound or a condensate thereof.

(但，R¹ 為取代或非取代的碳原子數1～6的一價烴基，R⁴ 為相同或相異種的碳原子數1～6之一價烴基)

(但，R² 為相同或相異種的取代或非取代之碳原子數1～6的一價烴基)

(但，R² 與上述相同。X為OH基或水解性基。)The organosilicon compound is a trifunctional silane compound represented by the following formula (II), a silazane compound represented by the following formula (III) or a monofunctional silane compound represented by the following formula (IV).

(However, R ¹ is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 6 carbon atoms, and R ⁴ is the same or different kind of monovalent hydrocarbon group having 1 to 6 carbon atoms)

(However, R ² is the same or different substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms)

(However, R ² is the same as above. X is an OH group or a hydrolyzable group.)

In the above formula (II), R ^{1 is} generally a monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, and particularly preferably 1 to 2 carbon atoms. Examples of the monovalent hydrocarbon group represented by R ¹ include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, butyl, and hexyl, and methyl, ethyl, and n-propyl are preferred. Group and isopropyl, particularly preferably methyl and ethyl. In addition, part or all of the hydrogen atoms of these monovalent hydrocarbon groups may be substituted with halogen atoms such as fluorine atoms, chlorine atoms, and bromine atoms, and preferably may be substituted with fluorine atoms.

In the above formula (II), R ^{4 is} generally a monovalent hydrocarbon group having 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, and particularly preferably 1 to 2 monovalent hydrocarbon groups. Examples of the monovalent hydrocarbon group represented by R ⁴ include alkyl groups such as methyl, ethyl, propyl, and butyl, preferably methyl, ethyl, and propyl, particularly preferably methyl, Ethyl.

As the trifunctional silane compound represented by the above formula (II), for example, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n- Propyl trimethoxy silane, n-propyl triethoxy silane, isopropyl trimethoxy silane, isopropyl triethoxy silane, butyl trimethoxy silane, butyl triethoxy silane, hexyl Trialkoxysilanes such as trimethoxysilane, trifluoropropyltrimethoxysilane, and heptafluorodecyltrimethoxysilane, etc., preferably methyltrimethoxysilane, methyltriethoxy Silane, ethyl trimethoxy silane, ethyl triethoxy silane, more preferably methyl trimethoxy silane, methyl triethoxy silane, or these partial hydrolysis condensation products.

Regarding the above formula (III) and formula (IV), R ² is a carbon number of 1 to 6, preferably a carbon number of 1 to 4, and particularly preferably a carbon number of 1 to 2 monovalent hydrocarbon group. Examples of the monovalent hydrocarbon group represented by R ² include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, etc., preferably methyl, ethyl, propyl, and particularly preferred For, methyl, ethyl. In addition, part or all of the hydrogen atoms of these monovalent hydrocarbon groups may be substituted with halogen atoms such as fluorine atoms, chlorine atoms, and bromine atoms, and preferably may be substituted with fluorine atoms.

As the hydrolyzable group represented by X in the above formula (IV), for example, a chlorine atom, an alkoxy group, an amino group, an acyloxy group, etc. can be mentioned, preferably an alkoxy group, an amino group, and particularly preferred出alkoxy group.

Examples of the silazane compound represented by the above formula (III) include hexamethyldisilazane, hexaethyldisilazane, and the like, and preferably hexamethyldisilazane.

Examples of monofunctional silane compounds represented by the above formula (IV) include monosilanol compounds such as trimethylsilanol and triethylsilanol, and monochlorosilanes such as trimethylchlorosilane and triethylchlorosilane. , Trimethylmethoxysilane, trimethylethoxysilane and other monoalkoxysilanes, trimethylsilyldimethylamine, trimethylsilyldiethylamine and other monoaminosilanes, trimethyl Monooxysilanes such as methyl acetoxysilane, preferably trimethylsilanol, trimethylmethoxysilane, trimethylsilyldiethylamine, particularly preferably trimethyl Silanol, trimethylmethoxysilane.

Synthetic silica particles can be roughly classified into combustion silica, deflagration silica, wet silica, and sol-gel silica (the so-called Stoeber method) according to the preparation method. Among them, the silica by the sol-gel method is preferable because the silanol group existing inside can absorb water more efficiently.

Hereinafter, an example of a preferable method for producing the surface-treated hygroscopic silica particles of the present invention by the sol-gel method will be described.

(但，R³ 為相同或相異種的碳原子數1～6之一價烴基)所示4官能性矽烷化合物或其部分水解生成物，或此等混合物，在鹼性物質的存在下，藉由在親水性有機溶劑與水之混合液中進行水解、縮合，得到含有SiO₂ 單位的親水性二氧化矽微粒子的混合溶劑分散液之步驟； 步驟(A2)：於上述親水性二氧化矽微粒子之混合溶劑分散液中，添加下述式(II)所示3官能性矽烷化合物或其部分水解生成物，或此等混合物，藉由處理上述親水性二氧化矽微粒子之表面，於上述親水性二氧化矽微粒子之表面上導入R¹ SiO_3/2 單位(但，R¹ 與下述相同)，得到第一表面處理二氧化矽微粒子之混合溶劑分散液的步驟；

(但，R¹ 為取代或非取代的碳原子數1～20之一價烴基，R⁴ 為相同或相異種的碳原子數1～6之一價烴基) 步驟(A3)：藉由自上述第一表面處理二氧化矽微粒子的混合溶劑分散液除去上述親水性有機溶劑與水的一部分，並濃縮後得到第一表面處理二氧化矽微粒子之混合溶劑濃縮分散液的步驟； 步驟(A4)：於上述第一表面處理二氧化矽微粒子的混合溶劑濃縮分散液中，添加下述式(III)所示矽氮烷化合物，或下述式(IV)所示1官能性矽烷化合物或此等混合物，使上述第一表面處理二氧化矽微粒子的表面進一步進行處理而於上述第一表面處理二氧化矽微粒子的表面上導入R² ₃ SiO_1/2 單位(但，R² 與下述相同。)，得到第二表面處理二氧化矽微粒子之步驟；

(但，R² 為相同或相異種的取代或非取代之碳原子數1～6的一價烴基)

(但，R² 與上述相同。X為OH基或水解性基)。The method for producing surface-treated hygroscopic silica microparticles in the present invention includes the following steps: Step (A1): The following formula (I)

(However, R ³ is a monovalent hydrocarbon group with 1 to 6 carbon atoms of the same or different species.) The tetrafunctional silane compound or its partial hydrolysis product, or a mixture of these, in the presence of a basic substance, A step of hydrolyzing and condensing in a mixed liquid of a hydrophilic organic solvent and water to obtain a mixed solvent dispersion of hydrophilic silica particles containing SiO ₂ units; Step (A2): in the above hydrophilic silica particles To the mixed solvent dispersion, add the trifunctional silane compound represented by the following formula (II) or its partially hydrolyzed product, or these mixtures, and treat the surface of the hydrophilic silica particles to make the hydrophilic The step of introducing R ¹ SiO _3/2 units on the surface of the silica particles (but R ¹ is the same as the following) to obtain a mixed solvent dispersion of the first surface-treated silica particles;

(However, R ¹ is a substituted or unsubstituted monovalent hydrocarbon group with 1 to 20 carbon atoms, and R ⁴ is a monovalent hydrocarbon group with 1 to 6 carbon atoms of the same or different kind) Step (A3): from the above The step of removing a part of the hydrophilic organic solvent and water from the mixed solvent dispersion of the first surface-treated silica microparticles, and concentrating the mixed solvent dispersion of the first surface-treated silica microparticles; Step (A4): Add a silazane compound represented by the following formula (III), or a monofunctional silane compound represented by the following formula (IV), or a mixture thereof to the concentrated dispersion of the mixed solvent of the first surface-treated silica particles , The surface of the first surface-treated silica particles is further processed, and R ² ₃ SiO _1/2 unit is introduced on the surface of the first surface-treated silica particles. (However, R ² is the same as the following.) , The step of obtaining second surface-treated silica particles;

(However, R ² is the same or different substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms)

(However, R ² is the same as above. X is an OH group or a hydrolyzable group).

That is, the silica microparticles of the present invention are obtained through the following steps; Step (A1): Synthesis step of hydrophilic silica particles, Step (A2): Surface treatment step with trifunctional silane compound, Step (A3): concentration step, Step (A4): Surface treatment step by monofunctional silane compound; The following is a supplementary explanation of each step of steps (A1) ~ (A4) in order.

(但，R³ 為相同或相異種的碳原子數1～6之一價烴基)。-Step (A1): Synthesis Step of Hydrophilic Silica Microparticles- In this step, the 4-functional silane compound represented by formula (I) or its partially hydrolyzed product or these mixtures are in the presence of a basic substance, In a mixed liquid of a hydrophilic organic solvent and water, a mixed solvent dispersion of hydrophilic silica particles is obtained by hydrolysis and condensation;

(However, R ³ is a monovalent hydrocarbon group with 1 to 6 carbon atoms of the same or different kind).

The monovalent hydrocarbon group represented by R ³ includes, for example, methyl, ethyl, propyl, butyl, phenyl, etc., preferably methyl, ethyl, propyl, butyl, and particularly preferably Examples include methyl and ethyl. Preferred are alkyl groups having 1 to 4 carbon atoms, and particularly preferred are methyl and ethyl groups.

As the tetrafunctional silane compound represented by the above formula (I): Si(OR ³ ) ₄ , for example, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, etc. Alkoxysilane, tetraphenoxysilane, etc., preferably tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, particularly preferably, tetramethoxysilane , Tetraethoxysilane. In addition, examples of the partial hydrolysis condensation product of the tetrafunctional silane compound represented by formula (I) include methyl silicate and ethyl silicate.

The hydrophilic organic solvent is not particularly limited as long as it dissolves the tetrafunctional silane compound represented by the formula (I): Si(OR ³ ) ₄ , the partial hydrolysis condensation product and water, and is not particularly limited, for example, Alcohols, methyl cellosolve, ethyl cellosolve, butyl cellosolve, cellosolve acetate and other cellosolves, acetone, methyl ethyl ketone and other ketones, dioxane, tetrahydrofuran and other ethers, etc. Preferably, alcohols and cellosolves are used, and particularly preferably, alcohols are used.

(式中，R⁵ 為碳原子數1～6的1價烴基)。Examples of the alcohols include alcohols represented by the following formula (V);

(In the formula, R ⁵ is a monovalent hydrocarbon group having 1 to 6 carbon atoms).

The above formula (V): In R ⁵ OH, R ^{5 is} preferably a C 1 to 4 monovalent hydrocarbon group, particularly preferably 1 to 2 monovalent hydrocarbon group. Examples of the monovalent hydrocarbon group represented by R ⁵ include alkyl groups such as methyl, ethyl, propyl, isopropyl, and butyl, and preferably include methyl, ethyl, propyl, and isopropyl groups. The propyl group, more preferably, a methyl group and an ethyl group. Examples of the alcohol represented by the above formula (V) include methanol, ethanol, propanol, isopropanol, butanol, and the like, preferably methanol and ethanol. If the number of carbon atoms of the alcohol increases, the particle size of the generated silica particles will increase. Therefore, it is better to use methanol when the target small particle size silica particles are to be obtained.

Moreover, as said basic substance, ammonia, dimethylamine, diethylamine, etc. are mentioned, Preferably it is ammonia, diethylamine, Especially preferably, it is ammonia. After the required amount of these alkaline substances is dissolved in water, the resulting aqueous solution (alkaline) can be mixed with the above-mentioned hydrophilic organic solvent.

The amount of water used at this time is 0.5 mol for the total of 1 mol of the tetrafunctional silane compound represented by the above formula (I): Si(OR ³ ) ₄ and/or the hydrolyzed condensation product of its partial hydrolysis and condensation product. It is preferably ~5 mol, preferably 0.6 to 2 mol, more preferably 0.7 to 1 mol. The molar ratio of the hydrophilic organic solvent to water is preferably 0.5-10 in terms of mass ratio, preferably 3-9, more preferably 5-8. At this time, the larger the amount of the hydrophilic organic solvent, the more the expected small particle size silica particles.

The amount of the basic substance is 0.01-2 moles for the total of 1 mole of the tetrafunctional silane compound represented by the above formula (I): Si(OR ³ ) ₄ and/or the hydrocarbyloxy group of its partial hydrolysis condensation product Ears are preferred, preferably 0.02-0.5 mol, more preferably 0.04-0.12 mol. At this time, the smaller the amount of the alkaline substance, the easier it is to become the desired small particle size silica fine particles, and the larger the amount of the alkaline substance is, the easier it will become the large particle size silica fine particles.

The above formula (I): Si(OR ³ ) ₄ can be hydrolyzed and condensed by a well-known method, that is, by adding the above-mentioned compound to a mixture of a hydrophilic organic solvent and water due to a basic substance. The tetrafunctional silane compound represented by formula (I) and the like are carried out.

The concentration of silica particles in the mixed solvent dispersion of hydrophilic silica particles obtained in this step (A1) is generally 3-15% by mass, preferably 5-10% by mass.

(但，R¹ 為取代或非取代的碳原子數1～6之一價烴基，R⁴ 為相同或相異種的碳原子數1～6之一價烴基)。-Step (A2): Surface treatment step with a trifunctional silane compound- To the hydrophilic silica microparticle mixed solvent dispersion obtained in step (A1), add the trifunctional represented by the following formula (II) Silane compounds or their partially hydrolyzed products, or these mixtures, to treat the surface of hydrophilic silica particles, thereby introducing R ¹ SiO _3/2 units (but R ¹ is the same as below) to obtain a mixed solvent dispersion of the first surface-treated silica particles.

(However, R ¹ is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 6 carbon atoms, and R ⁴ is the same or different kind of monovalent hydrocarbon group having 1 to 6 carbon atoms).

This step (A2) is indispensable for the next step of the concentration step (A3) to suppress the aggregation of silica fine particles. If the agglomeration cannot be suppressed, each particle of the obtained silica-based powder cannot maintain the primary particle diameter. As a result, it may cause damage to the organic EL device or decrease the transmittance when the organic EL device is sealed. .

In the above formula (II), R ^{1 is} generally 1 to 20 carbon atoms, preferably 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, particularly preferably 1 to 2 carbon atoms monovalent Hydrocarbyl. Examples of the monovalent hydrocarbon group represented by R ¹ include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, butyl, hexyl, etc., preferably methyl, ethyl, n -Propyl and isopropyl, particularly preferably methyl and ethyl. In addition, part or all of the hydrogen atoms of these monovalent hydrocarbon groups may be substituted with halogen atoms such as fluorine atoms, chlorine atoms, and bromine atoms, and preferably may be substituted with fluorine atoms.

In the above formula (II), R ⁴ generally has 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, and particularly preferably 1 to 2 monovalent hydrocarbon groups. Examples of the monovalent hydrocarbon group represented by R ⁴ include alkyl groups such as methyl, ethyl, propyl, butyl, etc., preferably methyl, ethyl, and propyl, and particularly preferably Methyl, ethyl.

As the trifunctional silane compound represented by the above formula (II), for example, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n- Propyl trimethoxy silane, n-propyl triethoxy silane, isopropyl trimethoxy silane, isopropyl triethoxy silane, butyl trimethoxy silane, butyl triethoxy silane, hexyl Trialkoxysilanes such as trimethoxysilane, trifluoropropyltrimethoxysilane, and heptafluorodecyltrimethoxysilane, etc., preferably methyltrimethoxysilane, methyltriethoxysilane , Ethyl trimethoxy silane, ethyl triethoxy silane, more preferably methyl trimethoxy silane, methyl triethoxy silane or these partial hydrolysis condensation products.

The addition amount of the trifunctional silane compound represented by the above formula (II) is 0.001 to 1 mol, preferably 0.01 to 0.1 mol, particularly preferably 0.01 to 0.05 per mol of Si atom of the hydrophilic silica fine particles Mol. If the added amount is 0.01 mol or more, the dispersibility becomes better and better. In addition, if the above-mentioned addition amount is 1 mol or less, agglomeration of silica fine particles does not occur, which is preferable.

The concentration of the silica particles in the mixed solvent dispersion of the first surface-treated silica particles obtained in this step (A2) is generally 3% by mass or more and less than 15% by mass, preferably 5~ 10% by mass. If the concentration is 3% by mass or more, the productivity can be improved, and if the concentration is less than 15% by mass, agglomeration of silica fine particles is not generated, which is preferable.

-Step (A3) Concentration Step- By removing a part of the hydrophilic organic solvent and water from the mixed solvent dispersion of the first surface-treated silica particles obtained in the above step (A2) and concentrating, the desired concentrated first surface-treated silica particles can be obtained The mixed solvent concentrates the dispersion. At this time, the hydrophobic organic solvent is added in advance, or it can also be added in the step. As for the hydrophobic solvent used, hydrocarbon-based and ketone-based solvents are preferred. Specific examples include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, etc., and methyl isobutyl ketone is preferred. Examples of methods for removing a part of the hydrophilic organic solvent and water include distillation and vacuum distillation. In the obtained concentrated dispersion liquid, the concentration of the silica particles is preferably 15-40% by mass, preferably 20-35% by mass, and more preferably 25-30% by mass. If the concentration of the above-mentioned silica particles is 15% by mass or more, the subsequent surface treatment can be smoothly performed. If the concentration is 40% by mass or less, agglomeration of the silica particles will not occur, which is preferable.

This step (A3) is an indispensable step to suppress the following problems, which are the silazane compound represented by formula (III) and formula (() used as a surface treatment agent in the next step (A4) IV) The monofunctional silane compound reacts with alcohol or water to make the surface treatment insufficient, and agglomeration occurs during subsequent drying, and the obtained silica powder cannot maintain the primary particle diameter.

(但，R² 為相同或相異種的取代或非取代之碳原子數1～6的一價烴基)

(但，R² 與上述相同。X為OH基或水解性基)-Step (A4): Surface treatment step by monofunctional silane compound-Add the silicon represented by the following formula (III) to the mixed solvent concentrated dispersion of the first surface-treated silica particles obtained in Step (A3) A azane compound, or a monofunctional silane compound represented by the following formula (IV), or a mixture of these, by subjecting the surface of the first surface-treated silica fine particles to further surface treatment, and then the first surface-treated silica R ² ₃ SiO _1/2 units are introduced into the surface of the fine particles (however, R ² is the same as described below) to obtain second surface-treated silica fine particles. In this step, the silanol groups remaining on the surface of the first surface-treated silicon dioxide microparticles by the above-mentioned treatment are triorganosilylated, and R ² ₃ SiO _1/2 units are introduced into the surface .

(However, R ² is the same or different substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms)

(However, R ² is the same as above. X is an OH group or a hydrolyzable group)

In the above formulas (III) and (IV), R ² is a carbon number of 1 to 6, preferably a carbon number of 1 to 4, and particularly preferably a carbon number of 1 to 2 monovalent hydrocarbon group. Examples of the monovalent hydrocarbon group represented by R ² include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, etc., preferably methyl, ethyl, and propyl, and particularly preferably Examples include methyl and ethyl. In addition, a part or all of the hydrogen atoms of these monovalent hydrocarbon groups may be substituted by halogen atoms such as fluorine atoms, chlorine atoms, and bromine atoms, and preferably may be substituted by fluorine atoms.

The hydrolyzable group represented by X in the above formula (IV) includes, for example, a chlorine atom, an alkoxy group, an amino group, an acyloxy group, etc., preferably an alkoxy group, an amino group, and particularly preferably an alkyl group. Oxy.

Examples of the silazane compound represented by the above formula (III) include hexamethyldisilazane, hexaethyldisilazane, and the like, and preferably hexamethyldisilazane.

Examples of monofunctional silane compounds represented by the above formula (IV) include monosilanol compounds such as trimethylsilanol and triethylsilanol, and monochlorosilanes such as trimethylchlorosilane and triethylchlorosilane. , Trimethylmethoxysilane, trimethylethoxysilane and other monoalkoxysilanes, trimethylsilyldimethylamine, trimethylsilyldiethylamine and other monoaminosilanes, trimethyl Monooxysilanes such as ethoxysilane, preferably trimethylsilanol, trimethylmethoxysilane, trimethylsilyldiethylamine, particularly preferably trimethylsilanol , Trimethylmethoxysilane.

The usage amount of the above-mentioned silazane compound and monofunctional silane compound is preferably 0.1-0.5 mol, preferably 0.2-0.4 mol, for 1 mol of Si atom of the hydrophilic silica fine particles. Preferably, it is 0.25 to 0.35 mol. If the usage amount is 0.1 mol or more, the dispersibility can be improved, so it is preferred. Moreover, if the above-mentioned usage amount is 0.5 mol or less, it is economically advantageous, so it is preferable.

For the obtained surface-treated hygroscopic silica fine particles, since they are easy to absorb moisture after drying, it is better to perform dehydration treatment when the silicone resin is added and mixed. Specifically, it is preferable to provide a dehydration treatment step of drying surface-treated hygroscopic silica fine particles at a temperature of 100 to 150° C. under normal pressure or reduced pressure. When the surface-treated hygroscopic silica fine particles are dried by this treatment, it is preferable to adjust the moisture content to 0.5 to 2.0% by mass (the mass of the surface-treated hygroscopic silica fine particles).

The refractive index of the surface-treated hygroscopic silica fine particles of the present invention is in the range of 1.39 to 1.42. If the refractive index is out of the above range, the difference in refractive index with the silicone resin will increase and the transparency of the cured product obtained will be impaired.

The median diameter of the primary particle size distribution based on the volume of the surface-treated hygroscopic silica microparticles of the present invention is preferably 0.01 to 0.5 μm. If it is in this range, the transparency of the silicone resin composition due to the aggregation of fine particles is reduced, and damage to the device or generation of short circuits can be suppressed.

The added amount of the surface-treated hygroscopic silica fine particles of the present invention must be in the range of 1 to 70% by mass, preferably in the range of 10 to 70% by mass, for the entire silicone resin composition. If the added amount exceeds 70% by mass, it may cause difficulties in handling due to particle aggregation or increase in viscosity, or it may become difficult to defoam, or the permeability may decrease due to the inclusion of air bubbles. In addition, for an organic EL panel, since the agglomerate contacts the device, damage to the device or short circuit may occur, and stable light emission may not be obtained.

In addition, with regard to the added amount of the surface-treated hygroscopic silica fine particles, the hygroscopic capacity (amount capable of absorbing water) of the hygroscopic silicone resin composition is 1.0×10 ^-7 g/mm ³ or more The addition amount of is preferably 1.0×10 ^-6 g/mm ³ or more. If the moisture absorption capacity of the resin composition is less than 1.0×10 ^-7 g/mm ³ , sufficient moisture absorption cannot be obtained, and the durability when used in an organic EL panel may be deteriorated.

Regarding the hygroscopic silicone resin composition of the present invention, the mixing method of the silicone resin and the surface-treated hygroscopic silica fine particles is not particularly limited. For example, the following mixing method in an inert gas can be mentioned . That is, it is better to store the prepared silicone resin and the surface-treated hygroscopic silica fine particles in an inert gas with reduced moisture content. As the inert gas, N ₂ gas or Ar gas is preferable, and the moisture content is 1 ppm or less. In the above-mentioned inert gas, the above-mentioned silicone resin and the above-mentioned surface-treated hygroscopic silica fine particles are measured and mixed by an electronic balance or the like. After mixing, if necessary, use a rotating device using centrifugal force to defoam. If bubbles are not easy to remove, vacuum degassing can be performed.

Transparent sealing material for organic EL The hygroscopic silicone resin composition of the present invention is suitable for use as a transparent sealing material for organic EL because it is easy to obtain a transparent and thin film cured product. Specifically, it is preferable to use a cured product sheet having a thickness of 25 μm, and the total light transmittance measured by a method based on JIS K 7361-1:1997 is preferably 90% or more. If the total light transmittance of the cured product sheet is less than 90%, it may become disadvantageous if it is used in an organic EL panel having a top emission structure.

In addition, the moisture absorption capacity of the transparent sealing material for organic EL of the present invention must be 1.0×10 ^-7 g/mm ³ or more, preferably 3.0×10 ^-7 g/mm ³ or more. If the moisture absorption capacity of less than 1.0×10 ^-7 g/mm ³ is used as a sealing material for organic EL, the moisture absorption of the water flowing into the organic EL panel is poor, so the durability of the organic EL is low By.

Coating method of transparent sealing material for organic EL The above-mentioned hygroscopic silicone resin composition can be applied as a transparent sealing material on an organic EL element. The coating method can use common methods such as sub-packing method, injection method, and screen printing method. The film thickness when the transparent sealing material for organic EL is applied to the organic EL element is not particularly limited, but when an organic EL panel having a flexible structure is used, it is preferably in the range of 1 to 300 μm. In addition, in accordance with conditions such as the production of thin panels, the above-mentioned hygroscopic silicone resin composition may be directly coated on the organic EL device, or it may be used by the SiO or SiN film on the organic EL device.

When explaining the curing method of the transparent sealing material for organic EL, as the curing catalyst of the hygroscopic silicone resin composition, a platinum catalyst activated by irradiating light with a wavelength of 200 to 500 nm is used. The method of hardening the hygroscopic silicone resin composition irradiated with ultraviolet rays by standing in a predetermined environment is preferable. As the ultraviolet irradiation method, a UV-LED lamp with a wavelength of 365nm, a metal halide lamp, etc., is used as an ultraviolet light source. The method of irradiating an appropriate amount of ultraviolet rays can be exemplified. The wavelength is preferably 200-500nm, preferably 200-350nm. Light. From the perspectives of curing speed and discoloration prevention, the temperature during irradiation is preferably 20 to 80°C, the irradiation intensity is preferably 30 to 2,000 mW/cm ² and the amount of irradiation is 150 to 10,000 mJ/cm ² The one is better. There are no particular restrictions on the conditions when the composition irradiated with ultraviolet rays is allowed to stand and harden, but it is preferably hardened at 20 to 60°C for 1 minute to 1 day.

Filling method of transparent sealing material for organic EL The above-mentioned hygroscopic silicone resin composition is useful when filling the organic EL panel as a sealing material. The organic EL panel to which the hygroscopic silicone resin composition of the present invention is applied is, as an example, a glass substrate having an organic EL element in a structure that combines an anode, an organic layer, and a cathode to form a laminated anode, an organic layer, and a cathode. Hollow sealing structures such as glass or glass on a flat plate are preferred. In order to describe an example of the glass substrate of the organic EL element that is bonded to the digging glass in the opposite direction, the above-mentioned hygroscopic silicone resin composition is filled with the digging glass on the inner side, and the digging glass is laminated in a vacuum. The equipment for the upper and lower substrates is to align the glass substrate on which the organic EL element is laminated and the excavation glass filled with the hygroscopic silicone resin composition in opposing directions. At this time, at the end of the excavation glass, UV-curable epoxy resin can be applied with a dispenser or the like, and the organic EL element and the hygroscopic silicone resin composition will be in direct contact with the organic EL element and become the surrounding Filled structure sealed with epoxy resin. Furthermore, for the above-mentioned hygroscopic silicone resin composition, it is better to irradiate ultraviolet rays before filling. Under the conditions of ultraviolet irradiation, the liquid state is maintained for a certain period of time after ultraviolet irradiation, and it can be carried out slowly after curing. Next, while maintaining the filling structure, ultraviolet rays are irradiated to the end epoxy resin portion to complete the end seal. The above-mentioned hygroscopic silicone resin composition gradually hardens to be completely cured. In this way, the organic EL panel filled with the hygroscopic silicone resin inside the panel is completed.

Transparent desiccant for organic EL The cured product of the hygroscopic silicone resin composition of the present invention is in the organic EL panel and can be used as a transparent organic EL device for dehumidifying water vapor entering the organic EL without contacting the organic EL element. Desiccant is used.

Manufacturing method of transparent desiccant for organic EL As a molding method of the transparent desiccant for organic EL, a known molding method can be appropriately selected according to the shape or size of the intended molded product. For example, molding methods such as injection molding, compression molding, injection molding, calender molding, extrusion molding, coating, and screen printing can be exemplified. The curing conditions may be well-known conditions of the molding method used, generally 60 to 450°C, preferably 80 to 400°C, more preferably 120 to 200°C for a few seconds to 1 day. Forming time. In addition, for the purpose of reducing the low-molecular-weight silicone components remaining in the cured product, the temperature is 150 to 250°C, preferably 200 to 240°C, for 1 hour or more, preferably 1 to 70 hours. , More preferably, it can also be cured for 1-10 hours (Post cure) (2 times of vulcanization).

In addition, the above-mentioned hygroscopic silicone resin composition can be made into a sheet by ordinary methods such as screen printing, calendering, injection, and pressing, in addition to coating methods such as sub-packaging and injection. Use after conversion. At this time, the silicone rubber sheet formed by sheeting the hygroscopic silicone resin composition is preferably formed to a thickness of 1.0 μm to 2 mm, preferably 1.0 μm to 1 mm. If it is in this range, the total thickness of the organic EL device will not increase, and the desired effect of the present invention will be obtained.

How to use transparent desiccant for organic EL The above-mentioned transparent desiccant for organic EL is particularly useful when used in an organic EL panel. The organic EL panel using the transparent desiccant of the present invention is an organic EL element in which an anode, an organic layer, and a cathode are laminated on a substrate such as glass, and has a hollow sealing structure that incorporates digging glass in opposite directions. . In addition, as an example of using the transparent desiccant of the present invention, the inside of the excavation glass is folded into, and a predetermined amount of the organopolysiloxane composition is applied by dripping or dispensing or inkjet, etc. When the composition is hardened, the above-mentioned excavation glass is laminated to produce an organic EL panel, and the transparent desiccant of the present invention can be placed only on the organic EL element, and the desiccant becomes non-organic The state of EL element contact. That is, the method of using the above-mentioned transparent desiccant for organic EL is not a method of filling the organic EL panel with no gaps. It is a step to use the pre-formed transparent desiccant under non-contact organic EL elements. For easy. In addition, the method of using the above-mentioned transparent desiccant is that even if the transparent desiccant is in non-contact with the organic EL device, the low-molecular-weight siloxane in the desiccant will diffuse and accumulate in the organic EL panel, making it exist in the organic EL device. The vicinity of the fine particles at the time of formation is insulated, and the cathode and the anode have the effect of suppressing the so-called short-circuit phenomenon (Short phenomenon) through the particles. [Example]

Examples and comparative examples are shown below to illustrate the present invention, but the present invention is not limited to the following examples. And, as for the unit of the compounding amount, part means part by mass. In addition, Me represents a methyl group, Ph represents a phenyl group, and Vi represents a vinyl group. The refractive index was measured with a digital refractometer (RX-9000α from Atago). The weight average molecular weight is the weight average molecular weight converted from polystyrene obtained by GPC (gel permeation chromatography) analysis.

[Preparation of silicone resin (Preparation examples 1 to 3)] [Preparation example 1] As component (A) is dimethyl polysiloxane (weight average molecular weight) whose ends are blocked with Me ₂ ViSiO _1/2 units 5,000), as the component (B), the organohydrogen polysiloxane represented by the following average formula (2) (weight average molecular weight 4,000), prepared per unit mass of the vinyl group bonded to the silicon atom of component (A) The mole number X (mol/g), the mole number of hydrogen atoms per unit mass (mol/g) bonded by silicon atoms of component (B) becomes 1.2.

In addition, as the component (C), 0.4% by mass of bis(acetedionate)platinum (II) acetic acid 2-(2-butoxyethoxy) was used for the total of the components (A) and (B). ) Ethyl ester solution (Platinum monomer is 1% by mass), and these components (A) to (C) are mixed with a planetary mixer (PLMG-350 Inoue) for 10 minutes to obtain liquid silicon with a refractive index of 1.402 Oxy resin.

[Preparation Example 2] Except for using organopolysiloxane having an average structure represented by the following formula (3) as the component (A), a silicone resin with a refractive index of 1.441 was obtained under the same procedure as in Preparation Example 1.

[Preparation Example 3] Except for using organopolysiloxane having an average structure represented by the following formula (4) as the component (A), a silicone resin with a refractive index of 1.425 was obtained under the same procedure as in Preparation Example 1.

[Synthesis of surface-treated hygroscopic silica microparticles (Synthesis Examples 1 to 5 and Comparative Synthesis Examples 1 to 3)] [Synthesis Example 1] ･Step (A1): "Synthesis Step of Hydrophilic Silica Microparticles" In a 3 liter glass reactor equipped with a stirrer, a dropping funnel, and a thermometer, 989.5 g of methanol, 135.5 g of water, and 66.5 g of 28% by mass ammonia were mixed and added. The solution was adjusted to 35°C, and 436.5 g (2.87 mol) of tetramethoxysilane was dropped over 6 hours while stirring. After the completion of the dropping, stirring was continued for another 0.5 hour to obtain a suspension of hydrophilic silica microparticles through hydrolysis.

･Step (A2): "Surface treatment step with trifunctional silane compound" In the suspension obtained in the above step (A1), 4.4 g (0.03 mol) of methyl trimethoxysilane was added dropwise at 25°C over 0.5 hours, and the stirring was continued for 12 hours after the drop, by treating the dioxide On the surface of the silicon particles, a first surface-treated silica particle dispersion liquid is obtained.

･Step (A3): "Enrichment Step" Next, install an ester adapter and a cooling tube on the glass reactor, heat the dispersion obtained in the previous step at 60 to 70°C to distill out 1,021 g of a mixture of methanol and water, and obtain the first surface treatment A mixed solvent concentrate dispersion of silica particles. At this time, the content of silica fine particles in the concentrated dispersion was 28% by mass.

･Step (A4): "Surface treatment step with monofunctional silane compound" After adding 138.4 g (0.86 mol) of hexamethyldisilazane to the concentrated dispersion obtained in the previous step at 25°C, the dispersion was heated to 50-60°C and reacted for 9 hours. The silica particles in the dispersion are trimethylsilylized. Next, the solvent in the dispersion was distilled off at 130°C under reduced pressure (6,650 Pa) to obtain 186 g of second surface-treated silica microparticles [1].

[Synthesis Example 2] For Synthesis Example 1, in step (A1), the amount of methanol, water, and 28% by mass ammonia was replaced with 1,045.7 g of methanol, 112.6 g of water, and 33.2 g of 28% by mass ammonia. The others were similarly surface-treated silica particles. [2]188g.

[Synthesis Example 3] ･Step (A1): "Synthesis Step of Hydrophilic Silica Microparticles" In a 3 liter glass reactor equipped with a stirrer, a dropping funnel, and a thermometer, 623.7 g of methanol, 41.4 g of water, and 49.8 g of 28% by mass ammonia were mixed and added. The solution was adjusted to 35°C, and the addition of 1,163.7 g of tetramethoxysilane and 418.1 g of 5.4% by mass ammonia water was started simultaneously while stirring. The former was dropped over 6 hours and the latter was dropped over 4 hours. After the tetramethoxysilane was dropped, stirring was continued for 0.5 hours for hydrolysis to obtain a suspension of hydrophilic silica particles.

･Step (A2): Surface treatment step with trifunctional silane compound" Into the suspension obtained in the above step (A1), 11.6g of methyltrimethoxysilane (the equivalent of 0.01 in molar ratio for tetramethoxysilane) was dropped into the suspension at 25°C over 0.5 hours, and then dropped Then, stirring was performed for another 12 hours to obtain first surface-treated silica particles.

･Step (A3): "Enrichment Step" Next, install an ester adapter and a cooling tube in a glass reactor, add 1,440g of methyl isobutyl ketone to the dispersion obtained in the previous step, then heat it at 80-110°C, and distill out methanol and water over 7 hours A mixed solvent concentrated dispersion liquid of the first surface-treated silica particles is obtained.

･Step (A4): "Surface treatment step by monofunctional silane compound" To the concentrated dispersion obtained in the previous step, add 357.6 g of hexamethyldisilazane at 25°C, and heat to 120°C for 3 hours to react to trimethylsilylize the silica particles. The solvent after this was distilled off under reduced pressure to obtain 472 g of second surface-treated silica fine particles [3].

[Synthesis Example 4] Regarding the step (A1), the hydrolysis temperature of tetramethoxysilane was set to other than 27°C, and the same operation as in Synthesis Example 3 was performed to obtain 469 g of surface-treated silica fine particles [4].

[Synthesis Example 5] Regarding the step (A1), the hydrolysis temperature of tetramethoxysilane was set to other than 20°C, and the same operation as in Synthesis Example 3 was performed to obtain 461 g of surface-treated silica fine particles [5].

[Comparative Synthesis Example 1] Put 100g of deflagration silicon dioxide (trade name: SO-C1, manufactured by Admatex) into a 0.3-liter glass reactor with a pre-mixer and a thermometer, add 1g of pure water under stirring, and then add 60 Stir at °C for 10 hours. Next, after cooling to 25°C, 2 g of hexamethyldisilazane was added under stirring, and the mixture was sealed and stirred for another 24 hours. The temperature was raised to 120°C, and while passing nitrogen gas, the remaining raw materials and generated ammonia were removed to obtain 100 g of surface-treated silica fine particles [6].

[Comparative Synthesis Example 2] In a 0.3-liter glass reactor equipped with a stirrer and a thermometer, 100 g of deflagration silicon dioxide (trade name: SO-C1, manufactured by Admatex) was added, and 1 g of pure water was added under stirring, and then sealed at 60°C. Stir for 10 hours. Next, after cooling to 25°C, 1 g of methyltrimethoxysilane was added with stirring, and the mixture was sealed and stirred for another 24 hours. Next, 2 g of hexamethyldisilazane was added under stirring, and the mixture was sealed and stirred for another 24 hours. The temperature was raised to 120°C, and while passing nitrogen gas, the remaining raw materials and generated ammonia were removed to obtain 101 g of surface-treated silica fine particles [7].

[Comparative Synthesis Example 3] For step (A4), hexamethyldisilazane was not added, and the solvent in the dispersion was distilled off at 130°C under reduced pressure (6,650Pa), and the same operation as in Synthesis Example 1 was performed to obtain a surface treatment Silica particles [8]179g.

The surface-treated silica particles (surface-treated silica particles [1] to [8]) obtained in Synthesis Examples 1 to 5 and Comparative Synthesis Examples 1 to 3 were measured according to the following method. The results are shown in Table 1.

[Particle diameter] Add surface-treated silicon dioxide fine particles to 0.5% by mass in methanol, and disperse the fine particles by ultrasonic waves for 10 minutes, and use the dynamic light scattering method/laser Doppler method nanometer size distribution measuring device (Nikkiso ( (Stock) system, trade name: UPA-EX150) The particle size distribution was measured, and the median diameter (50% cumulative diameter) in the volume-based particle size distribution was used as the particle diameter.

[Refractive Index] To 20 g of a mixed solvent of toluene (refractive index 1.4962) and methyl isobutyl ketone (refractive index 1.3958), 1 g of surface-treated silica fine particles was added and dispersed. The refractive index is adjusted by the mixing ratio of the above-mentioned solvents, and the refractive index of the mixed solvent when the visible light transmittance of the dispersion reaches the highest is used as the refractive index of the surface-treated silica particles. In addition, the refractive index of the mixed solvent is a value measured at 25°C by a digital refractometer (Atago RX-9000α), and the visible light transmittance of the dispersion liquid is measured by a spectrophotometer ((stock) Hitachi High-Tech Science Company U-3900H) The average value of the light transmittance at a wavelength of 380 to 780 nm measured at 25°C.

[Water content rate] In an aluminum container, finely weigh 10 mg of the surface-treated silica particles (surface-treated silica particles [1] to [8]) obtained in Synthesis Examples 1 to 5 and Comparative Synthesis Examples 1 to 3, and use them as Differential differential thermal balance (Rigaku Electric Co., Ltd. model: TG8120) is used for measurement, and the weight loss rate at 25 to 200°C is used as the moisture content rate. The above-mentioned surface-treated silica fine particles were measured under the conditions of 30°C and 80RH% under atmospheric pressure, and the moisture content (a) during moisture absorption after 3 days of exposure was measured, and the reduced pressure conditions at 100°C and 100Pa The moisture content (b) during drying after 2 days of drying is used to evaluate the hygroscopicity by the difference between the two [(a)-(b)(wt%pt)]. Moreover, for the surface-treated silica fine particles of the present invention, (a)-(b) are preferably 4.0wt%pt or more.

[Manufacturing method of silicone resin composition] The surface-treated silica particles obtained in each of the above synthesis examples were dehydrated in advance under a reduced pressure of 100°C and 100 Pa for 2 hours, sealed in a closed container, and left to stand still. The moisture content is controlled below 1ppm in the tank where N ₂ gas is substituted. In addition, the silicone resin obtained in the above preparation example was placed in a box replaced with N ₂ gas whose moisture content was controlled below 1 ppm for 2 hours, and then the surface-treated silica particles were added and placed in a rotating stirring device. , The surface-treated silica particles are rotated and dispersed for 30 minutes. Thereafter, a vacuum degassing treatment was performed to obtain a silicone resin composition. In addition, the added amount of the above-mentioned surface-treated silica particles is a designated amount using an electronic balance.

[Examples 1 to 5, Comparative Examples 1 to 3] The following silicone resin composition was prepared according to the above-mentioned manufacturing method of the silicone resin composition. The silicone resin composition was based on the silicone resin (refracting) obtained in Preparation Example 1. Rate 1.402), the addition of each mass% of "1.0% by mass", "10.0% by mass", "50.0% by mass", and "70.0% by mass" to the entire composition is in the above Synthesis Examples 1 to 5 and Compare the surface-treated silica particles obtained in Synthesis Examples 1 to 3 (surface-treated silica particles [1] to [8]). In addition, the silicone resin composition is coated on a polycarbonate plate with a dam formed at the end, and after smoothing, a metal halide lamp (HANDY UV-100 manufactured by ORC) is used to irradiate the integrated radiation amount with an ultraviolet intensity of 10mW/cm ² 4,000mJ/cm ² to harden it. At this time, it was adjusted to a size of 38mm×38mm and a thickness of 25μm. After that, the polycarbonate plate was peeled off to obtain a silicone resin sheet containing surface-treated silica particles.

[Total light transmittance] For the obtained silicone resin sheet, the total light transmittance was measured with a transmittance measuring device (V-780 manufactured by JASCO Corporation). If the total light transmittance is 90% or more, it is evaluated as "〇", 85% or more is evaluated as "△", and if it is less than 85%, it is evaluated as "×". The results are shown in Table 2.

[Moisture absorption capacity] For the obtained silicone resin sheet, the weight before and after exposure for 3 days at 40°C and 90% is measured in a constant temperature bath, and the weight gain obtained is divided by the sheet volume (38mm×38mm× 0.025mm) Calculate the moisture absorption capacity (g/mm ³ ). The results are shown in Table 2.

As shown in Examples 1 to 5, for the silicone resin (refractive index 1.402) obtained in Preparation Example 1, when surface-treated silica particles with a refractive index of 1.396 are added [1] to [5], the silica particles The total light transmittance exceeds 90% in the range up to 70.0% by mass for the total amount. Since the refractive index difference between the silicone resin and the silica particles is small, the light reflection at the interface of the surface-treated silica particles is low, and it is considered to show high transmittance. On the other hand, as shown in Comparative Examples 1 and 2, the surface-treated silica fine particles [6] and [7] can show a total light transmittance of 85% or more when the addition amount is 1.0% by mass, but it is 10.0 When the mass% is above, the total light transmittance is less than 85%. This is that the refractive index of the surface-treated silica particles is 1.462, which means that the transmittance loss is caused by the difference in refractive index with the silicone resin. Also, as shown in Comparative Example 3, although the refractive index of the surface-treated silica particles [8] is 1.396, the surface treatment of the silica particles is insufficient, so when mixed with silicone resin, silica is generated. Agglomeration of fine particles results in loss of transmittance even if the addition amount is 1.0% by mass. Therefore, it can be seen that the surface treatment of the silica particles is important for obtaining the effect of preventing aggregation.

[Comparative Examples 4-8] For Examples 1 to 5, the addition amount of the surface-treated silica fine particles was set to 90.0% by mass for the total composition of each composition, and the silicone resin sheet was prepared under the same procedure as above. Materials, the moisture absorption capacity and total light transmittance are evaluated. The results are shown in Table 3.

As shown in Comparative Examples 4 to 8, when the addition amount of silica fine particles is 90.0% by mass, the total light transmittance is maintained at more than 85%. If the addition amount exceeds 90.0% by mass, when hydrophobic silica particles are added to the silicone resin, the fluidity is impaired and aggregated particles are likely to be present. In addition to the failure to obtain good dispersibility, defoaming is also difficult, resulting in low transmittance. The result of the loss. Therefore, from the results of the above table, it can be known that in order to obtain an extremely good transmittance, the upper limit of the addition amount is 70.0% by mass.

[Comparative Examples 9-14] Next, with regard to the manufacturing method of the silicone resin composition described above, the silicone resin (refractive index 1.441) obtained in Preparation Example 2 and the silicone resin (refractive index 1.425) obtained in Preparation Example 3 will be The surface-treated silica particles obtained in Synthesis Examples 1, 3 and Comparative Synthesis Example 1 (surface-treated silica particles [1], [3], and [6]) are set to "1.0 mass for the entire composition %", "10.0% by mass", "50.0% by mass", and "70.0% by mass". The silicone resin composition is added with each mass%, and the silicone resin sheet is made into a silicone resin sheet by the same procedure as above to absorb moisture Evaluation of capacity and total light transmittance. The results are shown in Table 4.

As shown in Comparative Examples 9-11, for the silicone resin (refractive index: 1.441) obtained in Preparation Example 2 and the silicone resin (refractive index: 1.425) obtained in Preparation Example 3, surface treatment dioxide with a refractive index of 1.396 was added When silicon particles [1], [3] and surface-treated silicon dioxide particles [6] with a refractive index of 1.462, the difference in refractive index with the silicone resin results in a total light transmittance of less than 85%.

[Manufacturing method of organic EL element] 1 (i) ~ (iv), using the transparent sealing material for organic EL of the present invention to illustrate the manufacturing method of organic EL devices. The manufacturing method includes laminating an anode electrode (102), a hole injection layer (103), a hole transport layer (104), and a light emitting layer (105) on an alkali-free glass (101) with a thickness of 1mm and a size of 50mm×50mm. ), an electron transport layer (106), an electron injection layer (107) and a cathode electrode (108) to form an organic EL element laminated glass body (109) (refer to FIG. 1(i)).

Next, in a box where the moisture content is controlled below 1ppm by replacing N ₂ gas, a non-alkali seal type with a concave excavation shape with a thickness of 1mm and a size of 42mm×42mm as shown in Figure 1(ii) is prepared separately On the 2mm wide part of the excavated end of the glass (110), an ultraviolet-curing epoxy resin (112) is applied with a dispenser. And the depth of the excavated part of the excavated glass is set to 25 μm.

Next, in the same box, prepare the above-mentioned silicone resin composition as a transparent sealing material in a glass container, and irradiate ultraviolet rays with a metal halide lamp (ORC HANDY UV-100) at an ultraviolet intensity of 10mW/cm ² until it becomes integral irradiation The amount is 2,000mJ/cm ² . Next, the transparent sealing material (111) irradiated with ultraviolet rays is filled in the portion of the excavation with a size of 38mm×38mm (the state shown in Fig. 1(iii)).

Next, as shown in FIG. 1(iv), the organic EL element laminated glass body (109) in the same box is attached to the arrangement direction of the organic layer in the glass before the transparent sealing material (111) is cured. Then, using a metal halide lamp (HANDY UV-100 manufactured by ORC), irradiate ultraviolet rays with an ultraviolet intensity of 10mW/cm ² to an integrated irradiation dose of 10,000mJ/cm ² , and then after epoxy resin, let it stand at 25°C for 3 hours. The transparent sealing material is cured to obtain an organic EL panel (113) as shown in FIG. 2.

[Examples 6-8, Comparative Examples 15, 16] The silicone resin (refractive index 1.402) used in preparation example 1 was mixed with "1.0% by mass" and "50.0% by mass" for the entire composition. "70.0% by mass" and "90.0% by mass" of the surface-treated silica fine particles [1] (refractive index 1.396, particle diameter 52nm) of the silicone resin composition obtained in Synthesis Example 1, according to the above " The organic EL panel was made by the procedure shown in the "Method of Manufacturing Organic EL Device" column, and the following durability and short-circuit defects were evaluated. The results are shown in Table 5. In addition, the moisture absorption capacity was calculated by the same method as in Example 1 and Comparative Example 4 described above. In addition, the organic EL panel shown in Comparative Example 16 is an organic EL panel in which the inside of the glass panel is filled with dry N ₂ gas instead of being sealed with a silicone resin composition.

[Durability] The obtained organic EL panel is exposed to a 60℃ and 90%RH environment using a high temperature and high humidity test tank. After 200 hours, it is taken out at 25℃ in the atmosphere with a current of 10mA/cm ² The density was driven to emit light, and an optical microscope (LV150N manufactured by Nikon) was used to observe the size and number of dark spots. A dark spot with a diameter of 5μm or more is used as the target. If the dark spot occupies less than 3% of the total light-emitting area, it is evaluated as "A: Excellent", and if it is 3% or more and less than 5%, it is evaluated as "B: Excellent", when 5% or more is evaluated as "C: Bad." Durability.

[Presence of short-circuit failure] Put the above organic EL panel in a high-temperature and high-humidity test tank and expose it to a 60°C and 90%RH environment for 1,000 hours. After taking it out in an atmosphere of 25°C, confirm that the organic EL panel is short-circuited. The presence or absence. Whether there is a short circuit, confirm whether there is light emission at a current input of 10mA/cm ² or more. If no light is seen, confirm whether there is a short circuit on the cathode. If there is a short circuit, separate the above short circuit by laser When the element near the trace reproduces the luminescence, the sample is defined as a sample that produces short-circuit failure. And for each of 5 samples, the number of samples with short-circuit failure is represented by the number [number of samples with short-circuit failure/5].

As shown in Table 5, for Example 6, in the durability test of the organic EL panel, the generation of dark spots can be seen after 800 hours, and evaluation "B" can be seen, and good results may be obtained. The added amount of silica particles is 1.0% by mass, and the moisture absorption of the panel is 4.0×10 ^-7 g/mm ³ . When the added amount of silica fine particles increases, the moisture absorption also increases. As shown in Examples 7 and 8, the durability of the organic EL panel is also improved. Also, in Examples 6 to 8, no short circuit was detected, and good results were obtained. However, as shown in Comparative Example 15, when the addition amount of silicon dioxide fine particles was 90.0% by mass, the occurrence of short circuits was seen. This is considered to be due to the contact of the organic EL element caused by the aggregated particles, and the small damage loss is the cause. In addition, the organic EL panel filled with dry nitrogen shown in Comparative Example 16 was evaluated as "B" at 200 hours and as "C" at 600 hours or less for the same durability test. This means that the luminescence loss is caused due to the inability to absorb moisture flowing into the organic EL panel.

[Examples 9-14] For the silicone resin (refractive index 1.402) obtained in Preparation Example 1, the surface-treated silica fine particles [4] (refractive index 1.396, particle diameter 171nm) obtained in Synthesis Example 4 were used, and those obtained in Synthesis Example 5 Surface-treated silica fine particles [5] (refractive index 1.396, particle diameter 482nm), for the entire composition, mixed at each mass% of "1.0 mass%", "50.0 mass%" and "70.0 mass%" The silicone resin composition of, was made into an organic EL panel by the procedure shown in the "Method of Manufacturing Organic EL Device" above, and the durability and short-circuit defects were evaluated in the same way as above. The results are shown in Table 6.

As shown in Table 6, with respect to Examples 9 to 11 and Examples 12 to 14, the same results as in the above Examples 6 to 8 were obtained.

[Comparative Examples 17-22] For the silicone resin (refractive index 1.402) obtained in Preparation Example 1, the surface-treated silica fine particles [6] (refractive index 1.462, particle diameter 300nm) obtained in Comparative Synthesis Example 1 and obtained in Comparative Synthesis Example 2 were used Surface-treated silica fine particles [7] (refractive index 1.462, particle diameter 300nm), for the entire composition, the mass% of "1.0 mass%", "50.0 mass%" and "70.0 mass%" are mixed The silicone resin composition of was made into an organic EL panel according to the procedure shown in the "Method of Manufacturing Organic EL Device" column above, and the durability and short-circuit defects were evaluated in the same way as above. The results are shown in Table 7.

As shown in Table 7, although the initial light emission of the organic EL panels of Comparative Examples 17-22 was good, there was a significant deterioration in durability. As shown in Table 1, due to the lack of hygroscopicity of the surface-treated silica particles [6], [7] used, it is considered that the moisture flowing into the organic EL panel cannot be absorbed. The moisture absorption capacity of the sealing material at this time is as shown in Comparative Example 19 and Comparative Example 22, respectively 2.4×10 ^-8 g/mm ³ , 2.2×10 ^-8 g/mm ³ , and 4.0× as shown in Example 6. 10 ⁷ g/mm ³ is compared to a value less than one digit.

101: alkali-free glass 102: anode electrode 103: hole injection layer 104: Electric hole transport layer 105: luminescent layer 106: electron transport layer 107: Electron injection layer 108: Cathode electrode 109: Organic EL element laminated glass substrate 110: Alkali-free mining glass 111: Transparent sealing material 112: UV-curing epoxy resin 113: Organic EL panel 114: Organic EL panel (without dripping organopolysiloxane composition)

[Fig. 1] A schematic diagram to explain a method of applying a transparent sealing material for organic EL in an embodiment of the present invention to an organic EL panel. [Fig. 2] A schematic diagram showing the organic EL panel obtained by the method of Fig. 1. [Fig. 3] A schematic diagram showing an organic EL panel manufactured without using a transparent sealing material for organic EL in the panel.

Claims (10)

A hygroscopic silicone resin composition containing silicone resin, and at least a part of the surface has surface-treated hygroscopic silicon dioxide particles with a coating formed by bonding an organosilicon compound or its condensate, and The hygroscopic silicone resin composition with a moisture absorption capacity of 1.0×10 ^-7 g/mm ³ or more is characterized in that the refractive index of the silicone resin and the refractive index of the silica particles are both 1.39 to 1.42. The content of the silicon dioxide microparticles in the entire silicone resin composition is 1 to 70% by mass, and the organosilicon compound is a trifunctional silane compound represented by the following formula (II) and silicon represented by the following formula (III) A nitrogen compound or a monofunctional silane compound represented by the following formula (IV);

(However, R ¹ is a substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms, and R ⁴ is the same or different monovalent hydrocarbon group with 1 to 6 carbon atoms);

(However, R ² is the same or different substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms);

(However, R ² is the same as above; X is an OH group or a hydrolyzable group). Such as the hygroscopic silicone resin composition of claim 1, wherein the silica particles are sol-gel silica particles. The hygroscopic silicone resin composition of claim 1 or 2, wherein the surface-treated hygroscopic silica fine particles have an intermediate diameter in the volume-based particle size distribution of 0.01 to 0.5 μm. The hygroscopic silicone resin composition of claim 1 or 2, wherein the silicone resin contains the following components (A) to (C); (A) Linear organopolysiloxane having at least 2 alkenyl groups in one molecule, (B) Organohydrogen polysiloxane having at least 2 hydrogen atoms bonded to silicon atoms in a molecule: The content is for 1 mole of alkenyl groups bonded to silicon atoms in component (A) , Equivalent to 1.0～2.0 moles of hydrogen atoms bonded to silicon atoms in component (B), (C) Hydrosilation catalyst. A method for producing a hygroscopic silicone resin composition, which is a method for producing the hygroscopic silicone resin composition of any one of claims 1 to 4, characterized in that the surface-treated hygroscopic silica The fine particles are manufactured by the following steps (A1) to (A4); Step (A1): by hydrolyzing the 4-functional silane compound represented by the following formula (I) or its partial hydrolysis product, or a mixture of these, The step of hydrolyzing and condensing in a mixed liquid of a hydrophilic organic solvent and water in the presence of an alkaline substance to obtain a mixed solvent dispersion of hydrophilic spherical silica particles containing SiO ₂ units;

(However, R ³ is a monovalent hydrocarbon group with 1 to 6 carbon atoms of the same or different species); Step (A2): Add the following formula to the mixed solvent dispersion of the hydrophilic spherical silica particles (II) The trifunctional silane compound or its partially hydrolyzed product, or a mixture thereof, is used to treat the surface of the hydrophilic spherical silica microparticles, and introduce it on the surface of the hydrophilic spherical silica microparticles R ¹ SiO _3/2 units (however, R ¹ is the same as the following) to obtain a mixed solvent dispersion of the first surface-treated spherical silica particles;

(However, R ¹ is a substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms, and R ⁴ is a monovalent hydrocarbon group with 1 to 6 carbon atoms of the same or different species); Step (A3): The step of removing a part of the hydrophilic organic solvent and water from the mixed solvent dispersion of the first surface-treated spherical silica particles, and concentrating to obtain a mixed solvent concentrated dispersion of the first surface-treated spherical silica particles; Step (A4): Add the silazane compound represented by the following formula (III) or the monofunctionality represented by the following formula (IV) to the concentrated dispersion of the mixed solvent of the first surface-treated spherical silica particles Silane compound or these mixtures, subject the surface of the first surface-treated spherical silica particles to the surface of the first surface-treated spherical silica particles to introduce R ² ₃ SiO _1/2 units (but , R ² is the same as below), the step of obtaining the second surface-treated silica particles;

(However, R ² is the same or different substituted or unsubstituted monovalent hydrocarbon group with 1 to 6 carbon atoms);

(However, R ² is the same as above, and X is an OH group or a hydrolyzable group). A transparent sealing material for organic EL, which is characterized by containing the hygroscopic silicone resin composition according to any one of claims 1 to 4. A transparent desiccant for organic EL, which is characterized by being made of a cured product containing the hygroscopic silicone resin composition of any one of claims 1 to 4. A method of using a transparent sealing material for organic EL, which is characterized by coating the transparent sealing material for organic EL as claimed in claim 6 on an organic EL element and hardening it for the user. A method of using a transparent sealing material for organic EL, which is characterized by filling the transparent sealing material for organic EL as claimed in claim 6 in a panel with an organic EL element inside and hardening it for the user. A method of using a transparent desiccant for organic EL, which is characterized by disposing the transparent desiccant for organic EL as claimed in claim 7 in a panel with organic EL elements inside and the user.

Images