KR20150057274A - Composite sheet, method for preparing the same and display apparatus comprising the same - Google Patents

Abstract

The present invention relates to a composite sheet, a method for manufacturing the same, and a display device including the same. The composite sheet includes: a matrix including a cross-linked product of silicon-based rubber which has a main chain formed by using a Grubbs catalyst; and a reinforcing material with which the matrix is impregnated. The matrix has a refractive index of 1.45 or greater and transmittance of 85% or greater at the wavelength of 550 nm.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite sheet, a method of manufacturing the same, and a display device including the composite sheet.

The present invention relates to a composite sheet, a method of manufacturing the same, and a display device including the composite sheet.

A substrate material for a display device is required to be small in size, thin, lightweight, impact resistance, and flexibility. As a material for replacing a glass substrate of a conventional display device, a substrate for a flexible display is spotlighted. For example, a silicone-based composite sheet impregnated with a glass cloth has been developed.

In order to ensure transparency of the composite sheet, the refractive indexes of the glass fiber cloth and the resin for the composite sheet matrix must match. Conventional siloxane-containing silicon-based rubbers should contain a large amount of phenyl groups in the polysiloxane for refractive index matching with the glass fiber foil. Polysiloxanes containing a large number of phenyl groups may have poor viscosity due to high viscosity, and refractive index matching may be performed with two or more refractive index The polysiloxane having different refractive indexes may not be mixed with each other and phase separation may occur, which may lower the transparency of the composite sheet.

In this regard, Korean Patent Publication No. 2010-0014391 discloses a method of impregnating a nanosubstrate-filled silicone composition comprising a hydrosilylation-curable silicone composition and a carbon nanomaterial into a fiber reinforcement, And a reinforcing silicone resin film produced according to the method.

A problem to be solved by the present invention is to provide a composite sheet including a crosslinked product of a silicone rubber which is easy to match refractive index to a reinforcing material.

Another problem to be solved by the present invention is to provide a composite sheet having high permeability even though it is formed of a mixture of silicone rubber having a large refractive index difference.

The composite sheet of the present invention comprises a matrix; And a stiffener impregnated into the matrix, wherein the matrix may comprise a cross-link of a silicone-based rubber formed using a main chain grapse catalyst.

The method for producing a composite sheet according to the present invention includes a step of impregnating and crosslinking a mixture of a silicone rubber having at least one carbon-carbon double bond in its main chain formed by using a gluff catalyst to a reinforcing material, The refractive index difference between the rubber can be 0.03 or more.

A display device of the present invention includes: a substrate including the composite sheet; And a device member formed on the upper surface of the substrate.

The present invention provides a composite sheet comprising a crosslinked product of a silicone rubber which is easy to be index-matched to a reinforcing material, and a process for producing the composite sheet. The present invention provides a composite sheet having high transmittance even though it is formed of a mixture of silicone rubber having a large difference in refractive index, and a method for producing the same.

1 is a cross-sectional view of a composite sheet according to an embodiment of the present invention.
2 is a cross-sectional view of a composite sheet according to another embodiment of the present invention.
3 is a cross-sectional view of a display device according to an embodiment of the present invention.

The present invention is not limited to the above embodiments and various changes and modifications may be made by those skilled in the art without departing from the scope of the present invention. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

Hereinafter, a composite sheet according to an embodiment of the present invention will be described with reference to FIG. 1 is a cross-sectional view of a composite sheet according to an embodiment of the present invention.

1, the composite sheet 100 of one embodiment of the present invention includes a matrix 10 and a stiffener (not shown in FIG. 1) impregnated into the matrix 10, And a crosslinked silicone rubber formed using a Grubbs catalyst. Since the matrix 10 is formed of a silicon-based rubber formed by using a gypsum catalyst, not only the refractive index matching between the matrix and the stiffener is easy, but even if the matrix is formed of a mixture of silicone rubber having a large difference in refractive index for the purpose of refractive index matching with the stiffener, Can be high.

The silicone rubber is a hydrosilylation reaction site with a cross-linking agent for forming a matrix, and contains at least one double bond such as a carbon-carbon double bond, specifically an ethylenically unsaturated bond (* -CH = CH- *) in the main chain Wherein the double bond can be formed using a Grubbs catalyst. When the silicone resin having a high refractive index (refractive index: 1.45 or more) is polymerized, the viscosity increases greatly as the polymerization proceeds, which makes it difficult to produce a high-molecular-weight high-refractive-index silicone resin. However, Polymerization can be carried out up to a desired degree of polymerization. Further, even in the case of producing a matrix by mixing different kinds of silicon-based rubbers having a large refractive index difference, a transparent composite sheet can be obtained. This is because, when a silicone resin is produced using a grapz catalyst, a high-refractive-index silicon unit and a low-refractive-index silicon unit are repeatedly present in one silicon chain. Therefore, a silicon resin having a different refractive index and a different solubility and polarity It is because they can exist in a state of mixed well even if they are mixed.

Further, in order to ensure the transparency of the composite sheet, the refractive index of the matrix may be adjusted by using two or more kinds of silicone rubber so that the difference in refractive index between the reinforcing material and the matrix is small. When mixing different types of silicone rubber having a large refractive index difference, Phase separation may occur, resulting in an opaque silicone rubber mixture, and the composite sheet produced therefrom may be less transparent. On the other hand, in the case of producing a silicone rubber by using a gluvos catalyst, it is easy to match the refractive index with the reinforcing material even when a different type of silicone rubber having a large difference in refractive index is used, and also the transparency of the composite sheet is improved . For example, the matrix according to an embodiment of the present invention may be transparent even if it is formed of a mixture of silicon-based rubbers having a refractive index difference of 0.03 or more, more specifically 0.07 or more. Specifically, when a stiffener having a refractive index of about 1.53 is used, it is necessary to adjust the refractive index of the matrix to 1.53 0.03 or less in order to maintain transparency. In this case, even when a high refractive index silicone rubber containing an aromatic hydrocarbon group (e.g., an aryl group) having a high refractive index and a low refractive silicone rubber having a refractive index difference of not less than 0.03 with respect to the high refractive silicone rubber are used, It is possible to manufacture a transparent matrix. According to one embodiment, the matrix may have a refractive index of at least 1.45 and a transmittance of at least 85% at a wavelength of 550 nm, whereby the composite sheet may be transparent and the composite sheet may have a transmittance of at least 80% To 90% transmittance, and can be used for the flexible substrate of the composite sheet in the above range.

Further, even when two kinds of silicon-based rubbers having a large difference in refractive index are mixed, a transparent matrix can be easily produced, so that the refractive index matching with the reinforcing material can be facilitated by having a wide refractive index. In addition, the silicone rubber may have a wide weight average molecular weight by controlling the polymerization ratio of the siloxane monomer to improve the processability of the composite sheet. According to one embodiment, the silicone rubber may have a weight average molecular weight of 200 to 200,000 g / mol . In addition, the position of the double bond in the main chain of the silicone rubber can be precisely controlled by controlling the reaction conditions of the gross catalyst.

According to one embodiment, the silicone-based rubber may comprise one or more units of the formula 1:

≪ Formula 1 >

Wherein R ₁ , R ₂ , R ₃ and R ₄ are independently selected from the group consisting of hydrogen, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkyl group having 1 to 10 carbon atoms A cycloalkyl group having 2 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or an alkynyl group having 2 to 10 carbon atoms.

Specifically, R ₁ , R ₂ , R ₃ , and R ₄ may independently be an alkyl group having 1 to 5 carbon atoms, more specifically, a methyl group.

The silicone rubber further includes units of the following formulas (2), (3) and (4) to facilitate the refractive index matching with the stiffener and further increase the stiffness of the composite sheet:

(2)

Wherein R ₁ and R ₂ are independently selected from the group consisting of hydrogen, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, a cycloalkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 2 to 20 carbon atoms, An alkenyl group having 2 to 10 carbon atoms, or an alkynyl group having 2 to 10 carbon atoms).

(3)

R ₇ and R ₈ are independently selected from the group consisting of hydrogen, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, a cycloalkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 2 to 20 carbon atoms, An alkenyl group having 2 to 10 carbon atoms, or an alkynyl group having 2 to 10 carbon atoms).

≪ Formula 4 >

R ₉ and R ₁₀ independently represent hydrogen, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms, a cycloalkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 2 to 10 carbon atoms, An alkenyl group having 2 to 10 carbon atoms, or an alkynyl group having 2 to 10 carbon atoms).

Specifically, R _5, R ₆ is C 1 -C aryl group of 5 alkyl or C 6 -C 10, can be more specifically, a methyl group or a phenyl group, R _7, R _8, R _9, R ₁₀ is C 1 -C Lt; 5 > may be more specifically a methyl group.

For example, the silicone-based rubber may comprise units of the following formula:

≪ Formula 5 >

(Wherein R ₁₁ , R ₁₂ , R ₁₃ , R ₁₄ , R ₁₅ , R ₁₆ , R ₁₇ , R ₁₈ , R ₁₉ , R ₂₀ , R _{21 and} R ₂₂ independently represent hydrogen, A cycloalkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 20 carbon atoms or an alkynyl group having 2 to 10 carbon atoms, x is 1 to 50, y is 1 to 50 M is from 1 to 100, and n is from 1 to 100).

Specifically, the silicone-based rubber may be a copolymer of a first siloxane repeating unit having an aryl group, for example, an aryl group having 6 to 20 carbon atoms, and a second siloxane repeating unit having no aryl group, for example, an aryl group having 6 to 20 carbon atoms . For _{example, R 13, R 14, R} 15, R 16, R 21, R 22 more than one may be an aryl group having 6 to _{20, R 11, R 12,} R 17, R 18 in the formula (5) , R ₁₉ and R ₂₀ each independently represent hydrogen, an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or an alkynyl group having 2 to 10 carbon atoms.

The matrix may further comprise a crosslinking agent. The cross-linking agent is a monomolecule having two or more Si-H groups or an oligomer thereof, which undergoes a hydrosilylation reaction with the double bond at the main chain and the terminal end of the silicone rubber to form a matrix. The cross- linking agent includes a crosslinking agent commonly known in the silicon- can do. For example, the crosslinking agent may comprise units of the following formulas 6, 7, 8:

(6)

≪ Formula 7 >

(8)

(In the general formula 6 to 8, and * in a joint of the _{elements, R 23, R 24, R} 25, R 26, R 27, R 28, R 29, R 30 are independently hydrogen, having from 1 to 10 carbon atoms with each other An aryl group having 6 to 20 carbon atoms or a silyloxy group and at least two of R ₂₃ , R ₂₄ , R ₂₅ , R ₂₆ , R ₂₇ , R ₂₈ , R ₂₉ and R ₃₀ are hydrogen. The "silyloxy group" means an Si-O- group having an alkyl group having 1 to 10 carbon atoms or a hydrogen.

For example, the crosslinking agent may be represented by any of the following formulas (9) to (14):

≪ Formula 9 >

≪ Formula 10 >

≪ Formula 11 >

≪ Formula 12 >

≪ Formula 13 >

≪ Formula 14 >

(In the above formulas 9 to 14, Me is a methyl group, 0? X? 1, 0? Y? 1, 0? Z? 1, and x + y + z is 1).

The silicone rubber and the crosslinking agent may include A: B at a molar ratio of 1: 0.1 to 1: 5, for example, a molar ratio of 1: 1 to 1: 2, wherein A is the ratio of the weight of the silicone rubber Si-carbon carbon double bond-Si and Si-vinyl group in the cross-linking agent, and B is the number of moles of Si-H in the cross-linking agent relative to the weight average molecular weight of the cross-linking agent. In this range, the hydrosilylation reaction of the crosslinking agent and the silicone rubber can be completely performed, and the transparency of the composite sheet can be prevented from being lowered due to the crosslinking agent or the silicone rubber remaining unreacted.

The refractive index of the matrix resin (matrix) is 1.3 to 1.6. The refractive index difference between the matrix resin and the stiffener is small in the above range, so that the composite sheet can secure transparency. The matrix resin is contained in the composite sheet in an amount of 30 to 70% by weight, By weight and may have the effect of maintaining flexibility in the above range.

The reinforcing material may be included in the layered structure of the composite sheet, but the present invention is not limited thereto. The reinforcing material may be impregnated in the matrix 10 as a support of the composite sheet to be present therein. Although not shown in the drawings, the reinforcing material may be dispersed in a matrix, impregnated in a woven form, or impregnated in a uni-direction on the matrix. The stiffener may be formed as a single layer or a plurality of layers.

The stiffener is contained in the matrix to ensure rigidity and flexibility of the composite sheet. The refractive index of the stiffener may be 1.3 to 1.6, for example, 1.4 to 1.6. In this range, the refractive index with the matrix resin (matrix) So that the transparency of the composite sheet can be improved. According to one embodiment, the reinforcing material may comprise at least one of glass fiber, glass cloth, glass fabric, glass nonwoven fabric, glass mesh.

The refractive index difference between the stiffener and the matrix (the refractive index of the stiffener - the absolute value of the refractive index of the matrix resin) may be 0.1 or less. In this range, the composite sheet may have excellent transparency and transparency, 0.05, for example, 0.0001 to 0.05.

The reinforcing material may be contained in the composite sheet in an amount of 30 to 70% by weight, for example, 40 to 60% by weight. Within this range, there may be an effect of maintaining rigidity and reducing thermal expansion.

The composite sheet 100 may have a surface roughness Ra of 0 to 800 nm, for example, 0 to 500 nm, for example, 5 to 150 nm, and the composite sheet 100 may have a thermal expansion coefficient of 0 to 400 ppm / ° C., for example, 0 ppm / ° C. to 20 ppm / ° C., for example, 0 ppm / ° C. to 10 ppm / Within this range, thermal deformation can be suppressed during production of the flexible substrate. ASTM E 831 method is used to measure the dimensional change with temperature using a thermo-mechanical analyzer (expansion mode, force 0.05 N), and then to measure the change from the curve of the sample length according to the temperature (30-250 ° C) can do.

The composite sheet 100 may have a thickness of 50 to 200 mu m. In this range, it can be used as a substrate of a display device. The composite sheet 100 may have a modulus of 0.005 to 100 MPa, for example, 0.1 to 50 MPa. In the above range, there is an effect of maintaining the flexibility without being separated from the reinforcement.

In the composite sheet of another embodiment of the present invention, a barrier layer is further formed on at least one surface of the composite sheet to maximize gas barrier properties, moisture permeability, mechanical properties, and smoothness. Hereinafter, a composite sheet according to another embodiment of the present invention will be described with reference to FIG. 2 is a cross-sectional view of a composite sheet according to another embodiment of the present invention.

2, the composite sheet 200 of another embodiment of the present invention includes a matrix 10, a reinforcing material impregnated into the matrix 10, and a barrier layer 30 formed on the upper surface of the matrix 10, The matrix 10 may comprise a cross-link of a silicone-based rubber formed using a backbone catalyst. Although not shown in FIG. 2, the barrier layer 30 may be further formed on the lower surface of the matrix 10. Is substantially the same as the composite sheet of the embodiment of the present invention except that a barrier layer is further formed on the upper surface of the matrix. Hereinafter, the barrier layer will be described in detail.

The barrier layer 30 has characteristics of maximizing gas barrier properties, moisture permeability, mechanical properties, and smoothness. In order to realize the physical properties of the barrier layer and the physical properties of the composite sheet, the barrier layer can be laminated on both sides of the composite sheet.

The barrier layer 30 may have a thickness of 5 to 300 nm. In the above range, excellent surface flatness and effective moisture permeability control effect can be obtained without affecting the permeability.

The barrier layer 30 may include at least one of silicon nitride, silicon oxide, silicon carbide, aluminum nitride, indium tin oxide (ITO), and indium zinc oxide (IZO). In the barrier layer, two or more kinds of barrier layers may form a single layer, or different barrier layers may be laminated to form a plurality of layers. The barrier layer may be formed on the surface of the matrix by physical vapor deposition, chemical vapor deposition, coating, sputtering, evaporation, ion plating, wet coating, or organic inorganic multilayer coating.

The barrier layer 30 may have a modulus of 1 to 20 GPa, specifically 5 to 20 GPa. Within this range, it is possible to facilitate the lamination of any member on the barrier layer.

Hereinafter, a method of manufacturing a composite sheet according to an embodiment of the present invention will be described.

The method for producing a composite sheet according to an embodiment of the present invention includes a step of impregnating and crosslinking a reinforcing material to a mixture of a silicone rubber having at least one carbon-carbon double bond formed in its main chain using a gross catalyst, The refractive index difference between the rubber can be 0.03 or more. The composite sheet can be made transparent even if the refractive index difference of the silicone rubber is 0.03 or more by forming the matrix with the silicone rubber formed by using the gross catalyst.

The silicone-based rubber may be formed by polymerizing two or more kinds of siloxanes having two or more vinyl groups at the ends thereof under a gust catalyst. The siloxane having a vinyl group at the terminal thereof can be prepared by a conventional method. According to one embodiment, a mixture of an alkoxysilane monomer and a vinyl group silane monomer is hydrolyzed and polymerized, end capping with a vinyl-based siloxane monomer . According to one embodiment, the siloxane having a vinyl group at the terminal is obtained by hydrolyzing and polymerizing phenylmethyldimethoxysilane (PMDMS), end capping with 1,3-divinyltetramethyldisiloxane And the siloxane (hereinafter referred to as siloxane A) produced therefrom may have a refractive index of 1.3 to 1.6 and a weight average molecular weight of 500 to 20,000 g / mol. According to another embodiment, the siloxane having a vinyl group at the end can be prepared by hydrolysis and polymerization of dimethyldimethoxysilane (DMDMS, DMDMS, end-capped with 1,3-divinyltetramethyldisiloxane) The siloxane (hereinafter siloxane B) may have a refractive index of 1.3 to 1.6 and a weight average molecular weight of 500 to 20,000 g / mol.

The first to fourth generation catalysts may be used alone or in combination of two or more. Specific examples of the first to fourth generation catalysts may be used.

≪ Formula 15 >

(In the above formula (15), Ph is a phenyl group)

The reaction between a mixture of siloxanes having a vinyl group at the terminal and a gulose catalyst can be carried out by methods known to those skilled in the art. According to one embodiment, two siloxanes and a guggose catalyst are reacted at 100 to 200 DEG C for 1 to 24 hours Lt; / RTI > Within the above range, two kinds of siloxanes react with each other to sufficiently produce a silicone rubber. The gross catalyst can be included in an amount of 0.0001 to 0.1 equivalent based on the total siloxane sum, and the catalyst reaction can be completed in this range and the use of an unnecessary catalyst can be prevented.

The composition for a matrix includes two or more kinds of silicone-based rubbers having different refractive indexes for matching a refractive index with a reinforcing material. According to one embodiment, the second silicone-based rubber having a refractive index difference of 0.03 or more with respect to the first silicone- : 0.01 to 1:10. As described above, even if the first silicone rubber and the second silicone rubber have a refractive index difference of, for example, 0.03 or more, they can be mixed well without phase separation, 1.6, and the matrix produced therefrom has a good refractive index matching with the reinforcing material, so that the transparency and transparency of the composite sheet can be improved.

The total amount of Si-carbon carbon double bonds -Si and Si-vinyl groups in the silicone-based rubber relative to the weight average molecular weight of the silicone rubber and the crosslinking agent is 1: May be included in the composition at a molar ratio of 0.1 to 1: 5, for example, a molar ratio of 1: 1 to 1: 2. In this range, the hydrosilylation reaction of the crosslinking agent and the silicone rubber may completely take place, It is possible to prevent the transparency of the composite sheet from deteriorating due to the crosslinking agent or the silicone rubber.

The composition for the matrix may further include a conventional catalyst and an inhibitor in addition to the silicone rubber and the crosslinking agent. The catalyst is used for increasing the crosslinking reaction rate, and a catalyst commonly used in the production of a composite sheet can be used. For example, the catalyst may be a platinum-based or rhodium-based catalyst, a complex of platinum and an organic compound, a platinum-vinylated organosiloxane complex, a rhodium-olefin complex, or the like. Specifically, the catalyst may be a vinylalkylsilane platinum complex containing Karstedt catalyst, platinum black, chloroplatinic acid, chloroplatinic acid-olefin complex, chloroplatinic acid-alcohol coordination compound, or mixtures thereof.

The catalyst may comprise from 2 ppm to 2000 ppm, such as from 5 ppm to 500 ppm, based on the weight of the metal, of the silicone-based rubber. Within the above range, the crosslinking reaction rate between the silicone rubber and the crosslinking agent can be sufficiently increased, and unnecessary use of the catalyst can be prevented.

The inhibitor may be an inhibitor commonly used in the manufacture of composite sheets. For example, the inhibitor may be selected from the group consisting of acetylenic alcohols including dimethyl-1-hexyn-3-ol, pyridine, phosphine, organic phosphite, unsaturated amide, dialkylcarnosylate, dialkyl acetylenedicarboxylate, alkylated Maleic anhydride, maleic anhydride, diallyl maleate, or a mixture thereof. The inhibitor may be included at from 100 ppm to 2500 ppm for the silicone-based rubber. In the above range, there may be an effect of suppressing the hydrosilylation reaction at room temperature to enhance the storage stability.

The impregnation of the reinforcing material may include a step of impregnating and laminating the matrix composition with a reinforcing material. In order to lower the surface roughness of the composite sheet and to increase the curing rate by light transmission, for example, And then impregnating the matrix composition with a reinforcement.

Crosslinking may comprise a thermosetting or photo-curing or a combination thereof, heat curing may be performed at 50 to 150 ℃ for 1 minute to 1 hour, photo-curing is in the intensity of UV 10 to 100W / cm ² 1 Min to 5 min. Within the above range, the crosslinking reaction between the silicone rubber and the crosslinking agent can proceed sufficiently. The crosslinking may be carried out once, but may be carried out more than once for complete crosslinking of the composition.

The display device of one embodiment of the present invention may include the composite sheet. The display device may be, for example, a flexible liquid crystal display device, a flexible organic light emitting diode display device or the like, but is not limited thereto. The display device includes a substrate, a member for an apparatus formed on the upper surface of the substrate, and the member for the apparatus may include an organic light emitting element, a liquid crystal, or the like.

Hereinafter, a display device according to an embodiment of the present invention will be described with reference to FIG. 3 is a cross-sectional view of a display device according to an embodiment of the present invention.

3, a display device 300 according to an embodiment of the present invention includes a substrate 110, a buffer layer 25 formed on the substrate, a gate electrode 41 formed on the buffer layer 25, a gate electrode 41 And a buffer layer 25. The gate insulating film 40 may be formed of a material having a high dielectric constant. In the gate insulating film 40, an active layer 35 including source and drain regions 31, 32, and 33 is formed. An interlayer insulating film 51 having source and drain electrodes 52 and 53 is formed on the gate insulating film 40. A passivation layer 61 including a contact hole 62 is formed on the interlayer insulating film 51, A first electrode 70, and a pixel defining layer 80 are formed. The organic light emitting layer 71 and the second electrode 72 are formed on the pixel defining layer 80 and the substrate 110 may be formed of the composite sheet of the embodiments of the present invention.

Hereinafter, the present invention will be described in more detail by way of examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

Manufacturing example  1: Silicon Rubber  Produce

(1) Phenylmethyl dimethoxy silane (PMDMS) was weighed and hydrolyzed at 70 ° C for 1 hour under deionized water / potassium hydroxide (KOH). The reaction was allowed to proceed at 90 ° C, methanol as a side reaction material was removed, and the mixture was polymerized. Water was added thereto, and the mixture was cooled to room temperature. Then, 1,3-divinyltetramethyldisiloxane (Vi-MM) was added thereto, followed by end-capping at 50 ° C for about 5 hours. The mixture was washed with water at room temperature and the solvent was distilled off, 16 siloxane.

≪ Formula 16 >

(In the above Formula 16, Me is a methyl group, and x is 1 to 50).

(2) Dimethyldimethoxy silane (DMDMS) was weighed and hydrolyzed at 70 ° C for 1 hour under deionized water / potassium hydroxide. The reaction was allowed to proceed at 90 ° C, methanol as a side reaction material was removed, and the mixture was polymerized. Water was added thereto, and the mixture was cooled to room temperature. Then, 1,3-divinyltetramethyldisiloxane (Vi-MM) was added thereto, followed by end-capping at 50 ° C. for 5 hours. The mixture was washed with water at room temperature and the solvent was removed by a distiller to prepare a siloxane .

≪ Formula 17 >

(In the above formula (17), Me is a methyl group and y is 1 to 50)

(3) The prepared compound (16) and compound (17) were placed in a three-necked flask maintained at 23 DEG C and a small amount of a Grubbs second-generation catalyst (Aldrich) was added. The internal temperature of the flask was refluxed at 150 캜 for 12 hours, cooled to room temperature, and subjected to silica gel column treatment to remove the catalyst, thereby preparing a block copolymer type silicone rubber as the final glypopolysiloxane having the following formula (18).

≪ Formula 18 >

(In the formula (18), Me is a methyl group, x is 1 to 50, y is 1 to 50, m is 1 to 100, and n is 1 to 100)

Manufacturing example  2 to 8: Rubber  Produce

In Production Example 1, silicone rubbers having the refractive indexes shown in the following Table 1 were prepared while varying the addition equivalents of Formula (16) and Formula (17) as shown in Table 1 below.

Manufacturing example  9: Rubber  Produce

Siloxane was synthesized by changing the addition equivalent of PMDMS, DMDMS, and DMDMS to 5 wt% based on the sum of VMDMS, DMDMS, and vinylmethyldimethoxysilane (VMDMS, vinylmethyldimethoxysilane). PMDMS, DMDMS, VMDMS were weighed and hydrolyzed under deionized water / potassium hydroxide for 1 hour at 70 < 0 > C. The reaction was allowed to proceed at 90 ° C, methanol as a side reaction material was removed, and the mixture was polymerized. Water was added thereto, and the mixture was cooled to room temperature. Thereafter, 1,3-divinyltetramethyldisiloxane (Vi-MM) was added thereto, followed by end-capping at 50 ° C. for 5 hours. The mixture was washed with water at room temperature and the solvent was removed by a distillation to obtain a vinyl group- A silicone rubber (weight average molecular weight: 500 to 20,000 g / mol) was prepared.

(19)

(In the above formula (19), when Me is a methyl group and the sum of x + y + z is 100, the ratio of x: y: z has a ratio of (5 to 40): (5 to 80)

Manufacturing example  10 to 16: Rubber  Produce

A random silicone rubber having the refractive indices in Table 2 below was prepared while changing the contents of PMDMS, DMDMS and VMDMS in Production Example 9 as shown in Table 2 below.

Manufacturing example One 2 3 4 5 6 7 8 The siloxane of formula (16) 90 75 60 50 40 30 20 10 The siloxane of formula (17) 10 25 40 50 60 70 80 90 Refractive index of silicone rubber 1.543 1.516 1.491 1.473 1.460 1.446 1.428 1.406

Manufacturing example 9 10 11 12 13 14 15 16 PMDMS 90 75 60 50 40 25 10 0 DMDMS 5 20 35 45 55 70 85 95 VMDMS 5 5 5 5 5 5 5 5 Refractive index of silicone rubber 1.552 1.536 1.510 1.498 1.485 1.460 1.434 1.417

Example  1: Production of composite sheet

The silicone rubbers of Production Example 1 and Production Example 6 were mixed at a predetermined ratio and stirred to prepare a mixture. The mixture was evaluated for whether the silicone rubber was phase-separated from each other or whether it was transparent. (Dimethyl-1-hexyn-3-ol, TCI), a catalyst (platinum catalyst, Karstedt catalyst, Aldrich) was added to the mixture to prepare a matrix A composition was prepared. Glass fiber pellets (D-glass cloth, Owens corning, refractive index: 1.480) were placed on the film after the stirring, and the glass composition was poured into about 10 g of the composition for matrix, defoaming was carried out under vacuum, The laminate was laminated at a pressure of 0.1 MPa and cured at 100 DEG C for 30 minutes to prepare a composite sheet.

The transmittance of the composite sheet was measured at a wavelength of 550 nm. Specifically, the transmittance was measured using a UV-VIS SPECTROMETER (Lambda35, manufactured by PerkinElmer) at a wavelength of 550 nm for a composite sheet having a thickness of 100 mu m.

After mixing, the solution state and the cured state of the sheet were visually evaluated and evaluated as transparent and opaque.

Example  2 to 9: Production of composite sheet

A composite sheet was produced in the same manner as in Example 1, except that the types and blending ratios of the silicone rubber were changed as shown in Table 3 below. The permeability of the composite sheet was measured in the same manner.

Comparative Example  1: Production of composite sheet

The random silicone rubbers of Production Example 9 and Production Example 15 were mixed at a predetermined ratio and stirred to prepare a mixture. The mixture was evaluated for whether the silicone rubber was phase-separated from each other or whether it was transparent. The composition for matrix was prepared by adding a crosslinking agent (HMS-501, Si-H containing polymer, Gelest), an inhibitor (dimethyl-1-hexyn-3-ol, TCI) and a platinum catalyst (Karstedt catalyst, Aldrich) . Glass fiber pellets (D-glass cloth, Owens corning, refractive index: 1.480) were placed on the film after the stirring, and the glass composition was poured into about 10 g of the composition for matrix, defoaming was carried out under vacuum, The laminate was laminated at a pressure of 0.1 MPa and cured at 100 DEG C for 30 minutes to prepare a composite sheet. The transmittance of the composite sheet was measured at a wavelength of 550 nm.

Comparative Example  2 to 6: Production of composite sheet

A composite sheet was produced in the same manner as in Comparative Example 1, except that the types and blend ratios of the silicone rubber were changed as shown in Table 4 below. The permeability of the composite sheet was measured in the same manner.

High refractive index silicone rubber type and refractive index Low refractive index silicone rubber type and refractive index Difference in refractive index * Compounding ratio * Refractive index after mixing After mixing,
condition Sheet condition after hardening Composite sheet transmission
(%) Example
One Production Example 1 1.543 Production Example 6 1.446 0.097 16:84 1.462 Transparency Transparency 88.2 Example 2 Production Example 1 1.543 Production Example 7 1.428 0.115 30:70 1.461 Transparency Transparency 87.0 Example 3 Production Example 1 1.543 Production Example 8 1.406 0.137 41:59 1.460 Transparency Transparency 88.5 Example 4 Production Example 2 1.516 Production Example 6 1.446 0.070 23:77 1.462 Transparency Transparency 87.2 Example 5 Production Example 2 1.516 Production Example 7 1.428 0.088 39:61 1.461 Transparency Transparency 88.3 Example 6 Production Example 3 1.491 Production Example 6 1.446 0.045 36:64 1.463 Transparency Transparency 89.2 Example 7 Production Example 3 1.491 Manufacturing example
8 1.406 0.085 66:34 1.460 Transparency Transparency 88.6 Example 8 Production Example 4 1.473 Production Example 8 1.406 0.067 84:16 1.460 Transparency Transparency 88.8 Example 9 Production Example 5 1.460 Manufacturing example
7 1.428 0.032 97: 3 1.459 Transparency Transparency 87.9

High refractive index silicone rubber type and refractive index Low refractive index silicone rubber type and refractive index Difference in refractive index * Compounding ratio * Refractive index after mixing After mixing,
condition Sheet condition after hardening Composite sheet transmission
(%) Comparative Example
One Production Example 9 1.552 Production Example 15 1.434 0.118 23:77 1.461 opacity opacity 43.2 Comparative Example 2 Production Example 10 1.536 Production Example 15 1.434 0.102 26:74 1.460 opacity opacity 42.5 Comparative Example 3 Production Example 11 1.510 Production Example 15 1.434 0.076 36:64 1.463 opacity opacity 40.0 Comparative Example 4 Production Example 11 1.510 Production Example 16 1.417 0.093 47:53 1.462 opacity opacity 41.5 Comparative Example 5 Production Example 12 1.498 Production Example 16 1.417 0.081 54:46 1.460 opacity opacity 42.3 Comparative Example 6 Production Example 13 1.485 Production Example 15 1.434 0.051 53:47 1.463 opacity opacity 43.3

Compounding ratio: high refractive index silicone rubber: low refractive index silicone rubber ratio

* Difference in refractive index: difference in refractive index between high refractive index silicone rubber and low refractive index silicone rubber

As shown in Tables 3 to 4, the matrix formed of the silicone rubber formed by using the main chain graft catalyst of the present invention was transparent even after the mixing and after curing, even though the refractive index difference of the silicone rubber was large. The composite sheet also had high transparency.

On the other hand, the matrix of the comparative example formed of the silicone rubber not formed with the rubber catalyst of the present invention was opaque even after mixing and curing when the refractive index difference was large, and the permeability of the composite sheet was remarkably low.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (11)

matrix; And a reinforcing material impregnated into the matrix,
Wherein the matrix comprises a cross-linked product of a silicone-based rubber formed using a backbone catalyst. The composite sheet according to claim 1, wherein the matrix has a refractive index of 1.45 or more and a transmittance of 85% or more at a wavelength of 550 nm. The composite sheet according to claim 1, wherein the composite sheet has a transmittance of 80% or more at a wavelength of 550 nm. The composite sheet according to claim 1, wherein the refractive index difference between the stiffener and the matrix is 0.1 or less. The composite sheet according to claim 1, wherein the silicone rubber has at least one double bond in its main chain. The composite sheet according to claim 1, wherein the silicone rubber comprises a first siloxane repeating unit having an aryl group and a second siloxane repeating unit having no aryl group. The composite sheet according to claim 1, wherein the matrix is formed of a mixture of the silicone rubber having a refractive index difference of 0.03 or more. The composite sheet according to claim 1, wherein the reinforcing material comprises at least one of a glass fiber, a glass cloth, a glass fabric, a glass nonwoven fabric, and a glass mesh. The composite sheet according to claim 1, wherein a barrier layer is further formed on at least one surface of the composite sheet. And impregnating and crosslinking the reinforcing material to the mixture of the silicon-based rubbers having at least one carbon-carbon double bond formed in the main chain using a gross catalyst,
Wherein a difference in refractive index between the silicone rubber and the silicone rubber is 0.03 or more. A substrate comprising the composite sheet of any one of claims 1 to 9; And
And a device member formed on an upper surface of the substrate.

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