KR101450952B1 - The flexible display substrate - Google Patents

Abstract

The flexible display substrate of the present invention comprises a glass fiber layer and a resin layer formed on both sides of the glass bead layer, wherein the resin layer includes a unit structure from an acrylic monomer and a monomer structure from a monomer having a fluorene skeleton structure.

Description

[0001] The flexible display substrate [0002]

The present invention relates to a flexible display substrate.

In recent years, a plasma display panel (PDP), a liquid crystal display (LCD), an organic EL (Organic Light Emitting Diode), or the like, which is a flat panel display in a conventional CRT (Cathode Ray Tube) In particular, in the future, researches are being actively carried out in the world to realize such a flat panel display as a flexible display.

In such a flat panel display, a substrate is basically used as a glass substrate. In a typical flat panel display, a glass substrate is used as a most suitable material for a TFT (thin film transistor) because a high temperature heat treatment is required to form the TFT.

However, since the glass substrate has basically too rigid properties, it has poor flexibility and is not suitable as a substrate for a flexible display.

In comparison with glass substrates, flexible display substrates are excellent in weight, formability, non-destructiveness, and design. In particular, they can be manufactured by a roll-to-roll production method, However, there has not been developed a flexible display substrate of a plastic material suitable for commercialization yet.

In order for such a plastic substrate to be a substrate of a flexible display, basically excellent light transmittance is required, and a combination of properties such as thermal stability, chemical resistance and surface flatness are required in a complex manner. In particular, Coefficient of Thermal Expansion (CTE).

DISCLOSURE OF THE INVENTION The present invention is to provide a flexible display substrate having excellent optical properties and excellent thermal stability.

The flexible display substrate of the present invention comprises a glass fiber layer and a resin layer formed on both surfaces of the glass bead layer, wherein the resin layer includes a unit structure from an acrylic monomer and a unit structure from a cyclic olefin monomer, Is from 500 to 1,000,000. In this case, it is more preferable that the compound in the resin layer contains 25 to 400 parts by weight of the unit structure from the cyclic olefin-based monomer per 100 parts by weight of the unit structure from the acrylic monomer.

The cyclic olefin-based monomer forming the unit structure from the cyclic olefin-based monomer in the resin layer is bicyclo [2.2.1] hepta-2-ene, , 5-methyl-bicyclo [2.2.1] hepta-2-ene, 5-ethyl-bicyclo [2.2.1] hepta- (5-ethyl-bicyclo [2.2.1] hepta-2-ene), 5-propyl-bicyclo [2.2.1] hepta- ene), 5-hexyl-bicyclo [2.2.1] hepta-2-ene, 5-decyl-bicyclo [2.2.1] hepta- Hepta-2-ene, 5,6-dimethyl-bicyclo [2.2. Hepta-2-ene), 5-methyl-5-ethyl-bicyclo [2.2.1] hepta- , 5-phenyl-bicyclo [2.2.1] hepta-2-ene, 5-cyclohexyl-bicyclo [2.2.1] hepta- (5-cyclohexyl-bicyclo [2.2.1] hepta-2-ene), tricyclo [4.3.0.12,5] deca- clo [4.3.0.12,5] deca-3-ene, tetracyclo [4.4.0.12,5.17,10] dodeca- 3-ene (tetracyclo [4.4.0.12,5.17,10] dodeca- 3-methyl-tetracyclo [4.4.0.12,5.17,10] dodeca-8-ene (3-methyl-tetracyclo [4.4.0.12,5.17,10] dodeca- 8-ene), methyl 2-methyl-bicyclo [2.2.1] hepta- Methyl-bicyclo [2.2.1] hepta-5-ene-2-carboxylate), 2-methyl-bicyclo [2.2.1] hepta- 2-methyl-bicyclo [2.2.1] hepta-5-ene acrylate, 2-methyl- bicyclo [2.2.1] hept- -5-ene methacrylate, dimethyl bicyclo [2.2.1] hepta-5-ene-2,3-dicarboxylate, dimethyl bicyclo [2.2.1] hept- Diethyl bicyclo [2.2.1] hepta-5-ene-2,3-dicarboxylate), 3-methyl-3- Methoxycarbonyl-tetra 8-14-dodeca-8-ene), bicyclo [2.2.1] heptadeca-8-ene (3-methyl-3-methoxycarbonyl-tetracyclo [4.4.0.12,5.17,10] dodeca- N-cyclohexyl-2,3-maleimide), bicyclo [2.2.1] hepta-5-ene-N-cyclohexyl- 2-spiro-3'-N-phenylsuccinmide, bicyclo [2.2.1] hepta-5-ene- 2-spiro-3'-N-cyclohexylsuccinmide), 2 - [(3-ethyl 3-oxetanyl) methoxy] bicyclo [2.2.1] hepta-2-ene), 2 - [(3-ethyl-3-oxetanyl) methoxymethyl] bicyclo [2.2.1] hept- ] hepta-2-ene, 3-ethyl-3-oxetanyl) methylbicyclo [2.2.1] hept- Hepta-5-ene-2-carboxylate, 5-triethoxysilyl-bicyclo [2.2.1] hept- 2-ene, 5-methyldimethoxysilyl-bicyclo [2.2.1] hepta-2- ene), 5- [1'-methyl-2 ', 5'-dioxa-1'-silacyclopentyl] -bicyclo [2.2.1] hept- 2'-ene), 5'-dioxa-1'-silacyclopentyl] -bicyclo [2.2.1] hepta- ', 5'-dioxa-1'-silacyclopentyl] -bicyclo [2.2.1] hept-2-ene (5- [1'- methyl-3', 3 ', 4' 2 ', 5'-dioxa-1'-silacyclopentyl] -bicyclo [2.2.1] hepta-2-ene, 5- [1', 4 ' -'-silacyclohexyl] -bicyclo [2.2.1] hept-2-ene (5- [1 ', 4', 4'-trimethyl-2 'and 6'- dioxa-1'-silacyclohexyl] bicyclo [2.2.1] hepta-2-ene).

The cyclic olefin-based monomer forming the unit structure from the cyclic olefin-based monomer in the resin layer is preferably at least one selected from the general formula (1).

≪ Formula 1 >

Herein, R ₁ to R ₆ are the same or different and each represents a hydrogen atom or a hydrocarbon group of 1 to 10 carbon atoms which is unsubstituted or substituted with a linking group containing oxygen, nitrogen, sulfur or silicon, or a polar group, a single bond or a divalent linking group And the ring is selected from an aromatic group, a silane group and a halogen atom, and n is an integer of 1 to 10.

In consideration of light transmittance and thermal stability, it is preferable that n is 4 to 10 in the unit structure from the monomer of the formula (1).

The resin layer may comprise a unit structure from an acrylic monomer, a unit structure from a monomer of the formula (1) and a unit structure from a monomer of the following formula (2), wherein the compound is an acrylic monomer More preferably 50 to 200 parts by weight of the unit structure from the monomer of the formula (1) and 20 to 200 parts by weight of the unit structure of the monomer of the formula (2) based on 100 parts by weight of the unit structure from the monomer of the formula

(2)

Wherein R ₇ to R ₁₀ are hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms having a linking group including nitrogen, sulfur or silicon, or an aromatic group having a polar group, a single bond or a divalent linking group, A silane group and a halogen atom, and at least one of R ₇ to R ₁₀ includes a divalent linking group such as acrylate or methacrylate.

In the resin layer, the acrylic monomer forming the unit structure from the acrylic monomer is preferably an acrylic or methacrylic compound having two or more functional groups. The acrylic monomer is preferably bisphenol-A diacrylate, diacrylate, bisphenol-S diacrylate, dicyclopentadienyl diacrylate, pentaerythritol triacrylate, tris (2-hydroxyethyl) iso Acrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, pentaerythritol tetraacrylate, bisphenol-A dimethacrylate, bisphenol-S-dimethacrylate bisphenol-S dimethacrylate, dicyclopentadienyl dimethacrylate, pentaerythritol dimethacrylate, (2-hydroxyethyl) isocyanurate trimethacrylate, and pentaerythritol tetramethacrylate, which are used in the present invention. Or more.

The fluorene-based monomer forming the unit structure from the monomer of Formula 1 in the resin layer is not particularly limited and may be any fluorene skeleton-containing acrylate having two or more functional groups. Examples of the fluorene skeleton structure include 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, 9,9- 3-fluorophenyl) fluorene, 9,9-bis (4-hydroxy-3-bromophenyl) fluorene, 9,9-bis (4-hydroxy-3-methoxyphenyl) fluorene, 9,9-bis 3,5-dichlorophenyl) fluorene, and 9,9-bis (4-hydroxy-3,5-dibromophenyl) fluorene.

The glass fiber layer is formed by arranging glass fibers having a diameter of 4 to 20 占 m in one direction and forming a glass fiber layer having a thickness of 20 to 200 占 퐉 in a woven form in which warps and weft yarns are cross- .

The present invention provides a flexible display substrate having excellent optical properties while having excellent thermal stability.

1 is a graph of TGA analysis results of Examples 1 to 5 and Comparative Example 1;

The flexible display substrate of the present invention is a plastic substrate in which a glass fiber layer made of glass fiber is impregnated with a photosensitive resin composition to form a photosensitive resin composition layer on both sides of a glass fiber layer in order to maintain excellent optical properties as well as excellent thermal stability, And then adjusting the thickness thereof appropriately, followed by UV curing to form a resin layer.

In this case, the glass fiber layer may be aligned in one direction with the glass fibers having a diameter of 4 to 15 탆, and may be formed with a thickness of 20 to 200 탆. Such a glass fiber layer has excellent thermal properties, little. Because of its chemical durability, it does not corrode, has a strong tensile strength, has a small elongation, and has great electrical insulation.

The compound contained in the resin layer includes a unit structure from an acrylic monomer and a unit structure from a cyclic olefin monomer.

In this compound, the acrylic monomer can be variously selected according to the hydrophilic property and the hydrophobic property of the composition before curing and improves the compatibility of the composition before curing. Since there are many commercially available products having a viscosity ranging from 100 cPs to 50,000 cPs, the range of selection is wide and the photocuring progresses due to the radical formation of the photoinitiator. Therefore, the polymer is formed by photopolymerization and forms a network as a basic support of the film- .

In the case of a cyclic olefin monomer, it has a low viscosity and a high refractive index compound and has a stable aromatic molecular structure, and thus has a high glass transition temperature, thereby improving thermal stability. In addition, it has excellent abrasion resistance, which reduces the frequency of scratches and has excellent chemical resistance, which is a great help in not causing physical property changes in the subsequent processes and device fabrication.

It is preferable that the compound photopolymerized by the UV curing of the acrylic monomer and the cyclic olefin monomer has a weight average molecular weight of 500 to 1,000,000. When the weight average molecular weight is less than 500, there is a high possibility that fume generation and weight loss occur largely in the post-curing step. When the weight average molecular weight is more than 1,000,000, the film becomes hard and the flexibility is reduced have.

In this case, it is more preferable that the resin layer contains 25 to 400 parts by weight of the unit structure from the cyclic olefin-based monomer with respect to 100 parts by weight of the unit structure from the acrylic monomer. Within this content range, The substrate can be well-coordinated and become a more transparent substrate.

The cyclic olefin-based monomer forming the unit structure from the cyclic olefin-based monomer in the resin layer is bicyclo [2.2.1] hepta-2-ene, 5 -Methyl-bicyclo [2.2.1] hepta-2-ene, 5-ethyl-bicyclo [2.2.1] hepta- 5-ethyl-bicyclo [2.2.1] hepta-2-ene, 5-propyl-bicyclo [2.2.1] hepta- Hepta-2-ene, 5-hexyl-bicyclo [2.2.1] hepta- 5,6-dimethyl-bicyclo [2.2.1] hepta-2-ene, 5,6-dimethyl- bicyclo [2.2.1] hepta- hepta-2-ene, 5-methyl-5-ethyl-bicyclo [2.2.1] hepta- Phenyl-bicyclo [2.2.1] hepta-2-ene, 5-cyclohexyl-bicyclo [2.2.1] hepta- (5-cyclohexyl-bicyclo [2.2.1] hepta-2-ene), tricyclo [4.3.0.12,5] deca- 3-ene), tetracyclo [4.4.0.12,5.17,10] dodeca-3-ene (tetracyclo [4.4.0.12,5.17,10] dodeca- 3-methyl-tetracyclo [4.4.0.12,5.17,10] dodeca-8-ene (3-methyl-tetracyclo [4.4.0.12,5.17,10] dodeca- 8-ene), methyl 2-methyl-bicyclo [2.2.1] hepta- Methyl-bicyclo [2.2.1] hepta-5-ene-2-carboxylate), 2-methyl-bicyclo [2.2.1] hepta- 2-methyl-bicyclo [2.2.1] hepta-5-ene acrylate, 2-methyl- bicyclo [2.2.1] hept- -5-ene methacrylate, dimethyl bicyclo [2.2.1] hepta-5-ene-2,3-dicarboxylate, dimethyl bicyclo [2.2.1] hept- Diethyl bicyclo [2.2.1] hepta-5-ene-2,3-dicarboxylate), 3-methyl-3- Methoxycarbonyl-tetracycline [4.4.0.12,5.17,10] dodeca-8-ene (3-methyl-3-methoxycarbonyl-tetracyclo [4.4.0.12,5.17,10] dodeca-8- ene), bicyclo [2.2.1] N-cyclohexyl-2,3-maleimide), bicyclo [2.2.1] hepta-5-ene-N-cyclohexyl- 2-spiro-3'-N-phenylsuccinmide, bicyclo [2.2.1] hepta-5-ene- 2-spiro-3'-N-cyclohexylsuccinmide), 2 - [(3-ethyl 3-oxetanyl) methoxy] bicyclo [2.2.1] hepta-2-ene), 2 - [(3-ethyl-3-oxetanyl) methoxymethyl] bicyclo [2.2.1] hept- ] hepta-2-ene, 3-ethyl-3-oxetanyl) methylbicyclo [2.2.1] hept- Hepta-5-ene-2-carboxylate, 5-triethoxysilyl-bicyclo [2.2.1] hept- bicyclo [2.2.1] -hepta-2-ene, 5-methyldimethoxysilyl-bicyclo [2.2.1] hept- ene), 5- [1'-methyl-2 ', 5'-dioxa-1'-silacyclopentyl] -bicyclo [2.2.1] hept- 2'-ene), 5'-dioxa-1'-silacyclopentyl] -bicyclo [2.2.1] hepta- ', 5'-dioxa-1'-silacyclopentyl] -bicyclo [2.2.1] hept-2-ene (5- [1'- methyl-3', 3 ', 4' 2 ', 5'-dioxa-1'-silacyclopentyl] -bicyclo [2.2.1] hepta-2-ene, 5- [1', 4 '-'-silacyclohexyl] -bicyclo [2.2.1] hept-2-ene (5- [1 ', 4', 4'-trimethyl-2 'and 6'- dioxa-1'-silacyclohexyl] bicyclo [2.2.1] hepta-2-ene).

In particular, in order to greatly improve the light transmittance and thermal stability of the flexible display substrate of the present invention, the cyclic olefin monomer forming the unit structure from the cyclic olefin monomer in the resin layer is preferably a compound represented by the following formula . Such monomers are low-diffusing high-refractive-index compounds, which greatly improve the refractive index of the resin layer to minimize the refractive index with the glass fiber layer, thereby lowering the reflectance at the interface between the glass fiber layer and the resin layer to improve the overall light transmittance of the substrate You can. In addition, it has a stable aromatic molecular structure, has a high glass transition temperature, and greatly improves thermal stability. In addition, it has excellent abrasion resistance, which reduces the frequency of scratches and has excellent chemical resistance, which is a great help in not causing physical property changes in the subsequent processes and device fabrication.

≪ Formula 1 >

Herein, R ₁ to R ₆ are the same or different and each represents a hydrogen atom or a hydrocarbon group of 1 to 10 carbon atoms which is unsubstituted or substituted with a linking group containing oxygen, nitrogen, sulfur or silicon, or a polar group, a single bond or a divalent linking group The group is selected from an aromatic group, a silane group and a halogen atom, and n is an integer of 1 to 10.

 The hydrocarbon group having 1 to 10 carbon atoms may be any one selected from the group consisting of a methyl group, an ethyl group, a propyl group, and a combination thereof; A cyclopentyl group, a cyclohexyl group, and a combination thereof; An alkenyl group selected from the group consisting of a vinyl group, an aryl group, a propenyl group, and combinations thereof; , And the like.

The substituted or unsubstituted hydrocarbon group may be bonded to the ring structure directly or via a linking group as shown in Formula (1).

The linking group may be a bivalent hydrocarbon group having 1 to 10 carbon atoms, a linking group containing oxygen, nitrogen, sulfur or silicon such as a carbonyl group, an oxycarbonyl group, a sphone group, an ether bond, a thioether bond, A siloxane bond, and the like, or a linking group including a plurality of these groups.

The polar group includes a hydroxyl group, an alkoxy group having 1 to 10 carbon atoms, a carbonyloxy group, an alcoholic carbonyl group, a cyano group, an amide group, an imide group, an amino group, an acyl group, a sulfonyl group and a carboxyl group. More specifically, examples of the alkoxy group include a methoxy group and an ethoxy group. Examples of the carbonyloxy group include an alkylcarbonyloxy group such as an acetoxy group and a propionyloxy group, an ethoxycarbonyl group and the like. Is a primary amino group.

The divalent linking group in the aromatic group having a single bond or a divalent linking group is preferably an alkylene group having 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, such as a methylene group, an ethylene group, a trimethylene group, an arylene group, An alkylene group, an oxyarylene group, an oxycarbonyl group, an iminocarbonyl group, a carbonyl group, an acetylene group, a ureylene group, a hetero atom such as sulfur or oxygen, and an amino group. It is also possible to combine two or more of these connecting units.

The aromatic group should include an aromatic group through such a linkage, which includes a monohydroxy leaving group of an aromatic compound.

Specific examples of the monovalent hydrogen deficiency include benzene, pentane, naphthalene, azulene, heptarene, biphenylene, indacene, acenaphthalene, phenanthrene, anthracene, fluoransenes, , Naphthacene, prazene, picene, perylene, phenaphene, pentacene, tetraphenylene, hexaphene, penascene, rubicene, coronene, trinaphthylene, heptapene, And one or more of the group consisting of thiophene, thianthrene, furan, pyran, isobenzofuran, chromene, xanthene, phenoxathiine, pyrrole, imidazole, pyrazole, The present invention relates to a method for producing a compound represented by the general formula (1) or a salt thereof, wherein the compound is selected from the group consisting of isothiazole, isooxazole, pyridine, pyridine, pyrimidine, pyridine, indolidine, isoindole, indole, indazole, purine, quinolidine, isoquinone, quinoline, Xylylene, cyinoline, pteridine, carbazole, betacarbonyl, phenanthyridine, acry It is preferable to have any one of heterocyclic compounds and substituents thereof selected from the group consisting of pyridine, pyrimidine, phenanthroline, phenadine, phenarazine, phenothiazine, prazine, phenoxy and combinations thereof .

The silane group may be any one selected from the group consisting of a trimethoxysilyl group, a triethoxysilyl group, and a combination thereof, or any one selected from the group consisting of a trimethylsilic group, a triethylsilyl group, It is preferably a triorganosiloxy group.

Examples of the halogen atom include fluorine, chlorine, bromine and the like.

In the monomer of the formula (1), the light transmittance is improved by increasing the number n of the repeating unit of the alkylene oxide, but the thermal stability may be deteriorated. In view of light transmittance and thermal stability in this respect, it is preferable that n is 4 to 10 in the unit structure from the monomer of the above formula (1).

As a specific example, the fluorene-based monomer forming the unit structure from the monomer of Formula 1 is not particularly limited and may be any fluorene skeleton-containing acrylate having two or more functional groups. Examples of the fluorene skeleton structure include 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, 9,9- 3-fluorophenyl) fluorene, 9,9-bis (4-hydroxy-3-bromophenyl) fluorene, 9,9-bis (4-hydroxy-3-methoxyphenyl) fluorene, 9,9-bis 3,5-dichlorophenyl) fluorene, and 9,9-bis (4-hydroxy-3,5-dibromophenyl) fluorene.

In particular, in order to greatly improve the light transmittance and thermal stability of the flexible display substrate of the present invention, it is preferable that the resin layer further includes a unit structure from the monomer of Formula 2.

(2)

Wherein R ₇ to R ₁₀ are hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms having a linking group including nitrogen, sulfur or silicon, or an aromatic group having a polar group, a single bond or a divalent linking group, A silane group and a halogen atom, and at least one of R ₇ to R ₁₀ includes a divalent linking group such as acrylate or methacrylate.

The unit structure from the monomer of Formula 2 greatly improves the refractive index of the resin layer to minimize the refractive index with respect to the glass fiber layer, thereby lowering the reflectance at the interface between the glass fiber layer and the resin layer to improve the overall light transmittance of the substrate It is. In other words, the monomer of formula (2) has a high refractive index of 1.58 or more and has a high glass transition temperature, high degree of crosslinking and heat resistance. When the unit structure from the monomer of Formula 2 is included, the compound of the resin layer may contain 50 to 200 parts by weight of the unit structure from the monomer of Formula 1 based on 100 parts by weight of the unit structure from the acrylic monomer, More preferably 20 to 200 parts by weight of the unit structure from the glass fiber, and the refractive index of the glass fiber can be well matched within this content range, resulting in a more transparent substrate. When the unit structure from the monomer of the formula (1) and / or the monomer of the formula (2) is contained in an amount of more than 200 parts by weight based on 100 parts by weight of the unit structure from the acrylic monomer, the degree of curing becomes too high and the hardness of the substrate excessively increases, There is a possibility that the flexible performance is deteriorated.

In Formula 2, the hydrocarbon group having 1 to 10 carbon atoms is any one selected from the group consisting of a methyl group, an ethyl group, a propyl group, and a combination thereof; A cyclopentyl group, a cyclohexyl group, and a combination thereof; An alkenyl group selected from the group consisting of a vinyl group, an aryl group, a propenyl group, and combinations thereof; , And the like.

The substituted or unsubstituted hydrocarbon group may be bonded to the ring structure directly or via a linking group as shown in Formula (1).

The linking group may be a bivalent hydrocarbon group having 1 to 10 carbon atoms, a linking group containing oxygen, nitrogen, sulfur or silicon such as a carbonyl group, an oxycarbonyl group, a sphone group, an ether bond, a thioether bond, A siloxane bond, and the like, or a linking group including a plurality of these groups.

The polar group includes a hydroxyl group, an alkoxy group having 1 to 10 carbon atoms, a carbonyloxy group, an alcoholic carbonyl group, a cyano group, an amide group, an imide group, an amino group, an acyl group, a sulfonyl group and a carboxyl group. More specifically, examples of the alkoxy group include a methoxy group and an ethoxy group. Examples of the carbonyloxy group include an alkylcarbonyloxy group such as an acetoxy group and a propionyloxy group, an ethoxycarbonyl group and the like. Is a primary amino group.

Examples of the divalent linking group in the aromatic group having a single bond or a divalent linking group include an alkylene group having 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, such as a methylene group, an ethylene group, a trimethylene group, an arylene group, An arylene group, an oxyarylene group, an oxycarbonyl group, an iminocarbonyl group, a carbonyl group, an acetylene group, a ureylene group, a hetero atom such as sulfur or oxygen, and an amino group. It is also possible to combine two or more of these connecting units.

The aromatic group should include an aromatic group through such a linking group, which may include a monohydroxy leaving group of an aromatic compound.

Specific examples of the monovalent hydrogen deficiency include benzene, pentane, naphthalene, azulene, heptarene, biphenylene, indacene, acenaphthalene, phenanthrene, anthracene, fluoransenes, , Naphthacene, prazene, picene, perylene, phenaphene, pentacene, tetraphenylene, hexaphene, penascene, rubicene, coronene, trinaphthylene, heptapene, And one or more of the group consisting of thiophene, thianthrene, furan, pyran, isobenzofuran, chromene, xanthene, phenoxathiine, pyrrole, imidazole, pyrazole, The present invention relates to a method for producing a compound represented by the general formula (1) or a salt thereof, wherein the compound is selected from the group consisting of isothiazole, isooxazole, pyridine, pyridine, pyrimidine, pyridine, indolidine, isoindole, indole, indazole, purine, quinolidine, isoquinone, quinoline, Xylylene, cyinoline, pteridine, carbazole, betacarbonyl, phenanthyridine, acry It is preferable to have any one of heterocyclic compounds and substituents thereof selected from the group consisting of pyridine, pyrimidine, phenanthroline, phenadine, phenarazine, phenothiazine, prazine, phenoxy and combinations thereof .

The silane group may be any one selected from the group consisting of a trimethoxysilyl group, a triethoxysilyl group, and a combination thereof, or any one selected from the group consisting of a trimethylsilic group, a triethylsilyl group, It is preferably a triorganosiloxy group.

Examples of the halogen atom include fluorine, chlorine, bromine and the like.

On the other hand, in the resin layer, the acrylic monomer forming the unit structure from the acrylic monomer is preferably an acrylic or methacrylic compound having two or more functionalities, and the acrylic monomer is bisphenol-A-diacrylate ), Bisphenol-S diacrylate, dicyclopentadienyl diacrylate, pentaerythritol triacrylate, tris (2-hydroxyethyl) isocyanurate, Tris (2-hydroxyethyl) isocyanurate triacrylate, pentaerythritol tetraacrylate, bisphenol-A dimethacrylate, bisphenol-S-dimethacrylate, -S dimethacrylate, dicyclopentadienyl dimethacrylate, pentaerythritol, (2-hydroxyethyl) isocyanurate trimethacrylate, pentaerythritol tetramethacrylate, and the like, which are composed of pentaerythritol trimethacrylate, tris (2-hydroxyethyl) isocyanurate trimethacrylate, Lt; RTI ID = 0.0 > 1 < / RTI >

The photosensitive resin composition for forming the resin layer of the present invention further contains a photoinitiator in order to photo-cure them, in addition to the above-mentioned monomers in the main composition. The photopolymerization initiator in the present invention means a compound which generates an active species capable of initiating polymerization of the acrylic monomers and cyclic olefin monomers such as radicals, anions, and cations, causing decomposition or bonding by exposure. Here, the photoinitiator may be selected from conventional photoinitiators capable of photo-curing the acrylic monomer and the cyclic olefin monomer.

Examples of the photopolymerization initiator include Irgacure 907, Irgacure 369, Irgacure OXOl, Irgacure 242, thioxanthone, 2,4-diethylthioxanthone, thioxanthone-4-sulfonic acid, benzophenone, 4,4'- Ethylamino) benzophenone, acetophenone, p-dimethylaminoacetophenone,?,? - dimethoxyacetoxybenzophenone, 2,2'-dimethoxy-2-phenylacetophenone, p-methoxyacetophenone, 2 1-propanone, 2-benzyl-2-diethylamino-1- (4-morpholinophenyl) (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl phenyl ketone Ketones; Quinones such as anthraquinone and 1,4-naphthoquinone; Tri (trichloromethyl) -s-triazine, 1,3-bis (trichloromethyl) -5- (2- chlorophenyl) Halogen compounds such as phenylphenyl) -s-triazine, phenacyl chloride, tribromomethylphenylsulfone, and tris (trichloromethyl) -s-triazine; Peroxide such as di-t-butyl peroxide; Acylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and the like can be used. In the present invention, the photopolymerization initiator may be used alone or in combination.

The content of the photopolymerization initiator may be in the range of 0.5 to 20% by weight based on the total weight% of the composition. If the content of the photopolymerization initiator is less than 0.5% by weight, the sensitivity is insufficient and the conversion of the acrylic polymerization is 80% or less, tackiness of the sticky monomer may remain, and it is difficult to have the basic optical properties of the film to be formed. If the content of the photopolymerization initiator is more than 20% by weight, the light transmittance, haze, yellow index and the like of the formed film are liable to be lowered.

In order to control the viscosity of the photosensitive resin composition, a diluent is preferably included, and the content of the diluent is preferably 20 to 80% by weight.

As the diluent, the following materials may be used for preparing the composition or maintaining the viscosity. For example, alcohols such as methanol and ethanol, ethers such as tetrahydrofuran, diethylene glycol dimethyl ether and diethylene glycol diethyl ether, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol And propyleneglycol alkyl ether acetates such as butyl ether acetate. Among these diluents, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol methyl ether acetate, methyl ethyl ketone, cyclohexanone, 4-hydroxycyclohexanone and the like are preferable from the viewpoints of solubility, reactivity with each component, Hydroxy-2-methylpropionic acid, ethyl ester of 2-hydroxy-2-methylpropionic acid, ethyl ester of 2-hydroxypropionic acid, Methyl ester, ethyl ester, butyl ester of lactic acid, ethyl lactate, propyl lactate, methyl ester of butyl methoxyacetic acid, ethyl ester, propyl ester, butyl ester methyl ester, ethyl ester, propyl ester, butyl ester moiety of propoxyacetic acid Methyl esters, ethyl esters, Butyl ester 2-methoxypropionic acid methyl ester, ethyl ester, propyl ester, butyl ester methyl ester, 2-ethoxypropionic acid methyl ester, ethyl ester, propyl ester, butyl ester methyl ester of 2-butoxypropionic acid, ethyl ester , Propyl esters, butyl esters Methyl esters, ethyl esters, propyl esters, butyl esters of 3-methoxypropionic acid Methyl esters, ethyl esters, propyl esters, butyl esters of 3-ethoxypropionic acid Methyl esters of 3-butoxypropionic acid, ethyl The use of esters such as esters, propyl esters and butyl esters is preferred.

The diluent may also be used in combination with a high boiling point diluent. Examples of the high boiling point whitening agent which can be used include N-methylformamide, N, N-dimethylformamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, Ether.

The diluent is contained in an amount ranging from 20 to 80% by weight based on the total weight% of the composition. When the content of the diluent is within the above range, a desired film can be obtained.

In addition, surfactants, curing accelerators, antioxidants and the like may be further added for the purpose of expressing special functions.

Examples of the surfactant include fluorine and silicon surfactants such as FC-129, FC-170C and FC-430 of 3M, F- 172, F-173, F-183, F-470, F-475 and KP322, KP323, KP340 and KP341 of Shin-Etsu Silicones. Such a surfactant may be contained in an amount of 5 parts by weight or less, preferably 2 parts by weight or less, based on 100 parts by weight of the composition. When the content of the surfactant is more than 5 parts by weight, foaming occurs at the time of application, and such a problem is undesirable because it affects glass fiber impregnation and film-forming.

The resin composition of the present invention may contain a small amount of an antioxidant, an ultraviolet absorber, a dyeing pigment, and the like insofar as the properties such as transparency, solvent resistance and heat resistance are not impaired, if necessary.

Hereinafter, embodiments of the present invention will be described.

≪ Examples 1 to 5 and Comparative Example 1 >

The components and the contents (% by weight) as shown in Table 1 below were mixed and stirred for 3 hours to prepare a photosensitive resin composition. Then, a glass fiber layer having a thickness of 40 to 150 占 퐉 was impregnated and ultrasonic waves Then, the thickness of the resin layer on one side of the glass fiber layer was adjusted to 40 to 130 탆 by using a doctor blade, and then UV curing was performed to obtain a substrate.

The resin layer compound monomer
diluent
Photoinitiator Formula 1
Monomer Acrylic monomer E60 E90 Comparative Example 1 - 58 20 20 2 Example 1 38 20 20 20 2 Example 2 38 20 20 20 2 Example 3 38 20 20 20 2 Example 4 38 20 20 20 2 Example 5 38 20 20 20 2

Here, in Examples 1 to 5, the cyclic olefin-based monomer is a compound of Formula 1 (all R ₁ to R ₆ are hydrogen), n = 2 in Example 1, n = 4 in Example 2, n = 6 for Example 4, n = 8 for Example 4, n = 10 for Example 5, and E60 and E90 used as acrylic monomers were EBECRYL 9260 and EBECRYL 9390 products manufactured by SK CYTEC, Glycol ethyl ether acetate and Irgacure 907 and Irgacure 369 1: 1 as photoinitiators.

The results of evaluating the performance of Examples 1 to 5 and Comparative Example 1 thus obtained are shown in Table 2 and FIG. 1, and the measurement method for each evaluation item is as follows.

<Transmittance & Haze measurement method>

Using a haze meter (NDH2000 model, manufactured by Nippon Denshoku), measure the transmittance and haze of the film with a D65 light source in Method3. At this time, the wavelength is 550 nm.

<Measurement method of Y.I>

The yellow index of the film was measured using a UV-vis spectrometer (CARY-100 model, manufactured by Varian) using ASTM E313 measurement method.

<Refractive index>

Using an Abbe refractometer, the film was placed between the machines and measured at 25 ° C.

<Analysis method of thermogravimetric analyzer>

N ₂ the portion where the weight loss (%) generated with an elevated temperature at 600 ℃ 10 ℃ / min under the condition was observed with the focus.

<IR>

Transmittance values of 500 to 4000 cm ^-1 are measured with a reflection mode (equipped with a Smart Miracle accessory) using an FT-IR spectrophotometer (Thermo Nicolet Avatar 360 FT-IR product).

Transmittance (%) Haze (%) YI Comparative Example 1 89.06 42.57 6.7413 Example 1 90.15 13.7 6.2885 Example 2 90.25 7.2 6.3455 Example 3 90.87 29.03 6.4135 Example 4 90.50 12.3 6.1225 Example 5 91.71 17.31 6.0961

Thus, in Comparative Example 1, the light transmittance did not reach 90%, the haze exceeded 40%, and the YI value exceeded 6.5, but all of Examples 1 to 5 show superior optical properties to those of Comparative Example 1 have.

The results of analysis by a thermogravimetric analyzer (TGA) for the evaluation of thermal stability are the same as those of FIG. 1 (Y axis represents residual ratio (%) having thermal stability up to 600 DEG C in FIG. 1) Comparative Example 1, which did not contain olefin-based monomers, showed that the residual amount was about 40% by weight when the temperature was raised to 600 ° C, and that about 50% by weight or more remained in Examples 1 to 5, showing excellent thermal stability.

&Lt; Example 6 >

Trimethylol propane acetalization product diacrylate (R-604, manufactured by Nippon Kayaku) and 100 parts by weight of this trimethylol propane acetalization product diacrylate were added Tetrakis (glycidyloxyphenyl) ethane-GAC 25 And 100 parts by weight of fluorene acrylate having a divalent functional group (HR-6060, trade name, product of MIWON SPECIALTY CHEMICALS, R ₁ to R ₆ are all H and n is 3) 2 parts by weight of 1-hydroxycyclohexyl phenyl ketone (Irgacure 184, manufactured by Basf) and 30 parts by weight of propylene glycol ethyl ether acetate were further mixed based on 100 parts by weight of the monomer mixture to prepare a resin layer composition before curing. The resin layer composition before curing was impregnated with glass fibers having a thickness of 100 mu m and sonicated for 30 minutes. This was placed a release film 2 in the glass substrate 2, the glass fiber layer spreads into the center of the adjusted so that the thickness of the resin layer using a doctor blade 100㎛, as with UV light of about 10J / cm ² both And the glass substrate and the release film were removed to obtain a substrate.

&Lt; Example 7 >

Example 6 was repeated except that the content of Tetrakis (glycidyloxyphenyl) ethane-GAC corresponding to the monomer of Formula 2 was 50 parts by weight based on 100 parts by weight of trimethylol propane acetalization product diacrylate Substrate.

&Lt; Example 8 >

The procedure of Example 6 was repeated except that the content of Tetrakis (glycidyloxyphenyl) ethane-GAC corresponding to the monomer of Formula 2 was 100 parts by weight based on 100 parts by weight of trimethylol propane acetalization product diacrylate Substrate.

&Lt; Example 9 >

In Example 6, the monomer corresponding to the monomer of Chemical Formula 2 was changed to 1,1,2,2-Tetrakis [4- (acryloxy polyethoxy) phenyl] ethane and its content was changed to 100 parts by weight of trimethylolpropane acetalization product diacrylate A substrate was prepared in the same manner as in Example 6, except that 50 parts by weight was included as a reference.

&Lt; Example 10 >

In Example 9, the content of the monomer 1,1,2,2-Tetrakis [4- (acryloxy polyethoxy) phenyl] ethane corresponding to the monomer of Chemical Formula 2 was added to 100 parts by weight of trimethylolpropane acetalization product diacrylate A substrate was prepared in the same manner as in Example 6.

&Lt; Comparative Example 2 &

A substrate was prepared in the same manner as in Example 6, except that the monomer of Formula 2 was not contained in Example 6.

The results of evaluating the performance of Examples 6 to 10 and Comparative Example 2 thus obtained are shown in Table 3 below, and the measurement method of each evaluation item is as follows.

<Transmittance & Haze measurement method>

Using a haze meter (NDH2000 model, manufactured by Nippon Denshoku), measure the transmittance and haze of the film with a D65 light source in Method3. At this time, the wavelength is 550 nm.

<Tg measurement>

The temperature was measured at a heating rate of 10 DEG C / min using a model TGA-TGA7 of Perkin Elmer.

<Thermal Expansion Coefficient>

Using a model TMA-Diamond manufactured by Perkin Elmer, the temperature was raised at a rate of 10 DEG C for 1 minute under a nitrogen atmosphere, and a load of 1 g was applied. After raising the temperature from room temperature to 200 ° C at a rate of 10 ° C / min to remove the thermal history of the film, the temperature was further raised from room temperature to 300 ° C at a rate of 10 ° C / min to calculate the thermal expansion coefficient in the temperature range of 50 to 250 ° C .

Transmittance (%) Haze (%) Tg (占 폚) Thermal Expansion Coefficient (ppm) Comparative Example 2 91 3.6 211 18 Example 6 90 3.7 > 230 15 Example 7 90 6.2 > 230 14 Example 8 88 17.2 > 230 11 Example 9 90 3.3 > 230 14 Example 10 88 15.3 > 230 12

Examples 6 to 10 of the present invention show high light transmittance as in Comparative Example 2 even when glass fiber is used. By including the unit structure from the monomer of the formula (2), it can be seen that Examples 6 to 10 can obtain an excellent Tg of 230 DEG C or more and a thermal expansion coefficient of 15 ppm or less.

Claims (7)

A glass fiber layer and a resin layer formed on both sides of the glass fiber layer,
Wherein the resin layer comprises a compound having a weight average molecular weight of 500 to 1,000,000 and comprising 25 to 400 parts by weight of a unit structure from the monomer represented by the following formula 1 per 100 parts by weight of the unit structure from the acrylic monomer . Formula 1

Herein, R ₁ to R ₆ are the same or different and each represents a hydrogen atom or a hydrocarbon group of 1 to 10 carbon atoms which is unsubstituted or substituted with a linking group containing oxygen, nitrogen, sulfur or silicon, or a polar group, a single bond or a divalent linking group The branch is selected from an aromatic group, a silane group, and a halogen atom; n is an integer from 3 to 10; The flexible display substrate according to claim 1, wherein the glass fiber layer has a glass fiber having a diameter of 4 to 15 mu m oriented in one direction and a thickness of 20 to 200 mu m. The method of claim 1, wherein the compound in the resin layer comprises 50 to 200 parts by weight of a unit structure from the monomer of formula (1) and 20 to 200 parts by weight of a monomer structure of the monomer of formula (2), based on 100 parts by weight of the unit structure from the acrylic monomer By weight based on the total weight of the flexible display substrate.
(2)

Wherein R ₇ to R ₁₀ are hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms having a linking group including nitrogen, sulfur or silicon, or an aromatic group having a polar group, a single bond or a divalent linking group, A silane group and a halogen atom, and at least one of R ₇ to R ₁₀ includes a divalent linking group such as acrylate or methacrylate. The flexible display substrate according to claim 3, wherein the unit structure of the acrylic monomer in the resin layer is formed of an acrylic monomer selected from acrylic or methacrylic compounds having two or more functionalities. 5. The composition of claim 4, wherein the acrylic monomer is selected from the group consisting of bisphenol-A-diacrylate, bisphenol-S diacrylate, dicyclopentadienyl diacrylate, Acrylate, pentaerythritol triacrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, pentaerythritol tetraacrylate, bisphenol- Bisphenol-A dimethacrylate, bisphenol-S dimethacrylate, dicyclopentadienyl dimethacrylate, pentaerythritol triacrylate, pentaerythritol tetramethacrylate, trimethacrylate, tris (2-hydroxyethyl) isocyanurate trimethacrylate (tris (2-hydroxyethyl) isocyanurate trimethacrylate e), and pentaerythritol tetramethacrylate. 2. The flexible display substrate according to claim 1, [3] The method according to claim 1, wherein the unit structure from the monomer of the formula (1) in the resin layer has a fluorene backbone structure of 9,9-bis (4-hydroxyphenyl) fluorene, 9,9- 3-methylphenyl) fluorene, 9,9-bis (4-hydroxy-3-chlorophenyl) fluorene, 9,9- Bis (4-hydroxy-3-fluorophenyl) fluorene, 9,9-bis (4-hydroxy-3-methoxyphenyl) fluorene, -Dimethylphenyl) fluorene, 9,9-bis (4-hydroxy-3,5-dichlorophenyl) fluorene and 9,9-bis (4-hydroxy-3,5-dibromophenyl) fluorene And at least one selected from the group consisting of glass, glass, and glass. delete

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