KR20170079663A - Composition For Hard Coating and Hard Coating Film Including Cured Product Of The Same As The Coating Layer - Google Patents

Abstract

The present invention relates to a composition comprising a siloxane resin in which alkoxysilane and alkoxy metal compound are chemically bonded as a first component; And a hard coating film comprising a resin composition for hard coating and a cured product thereof as a hard coat layer, the hard coat film comprising at least one of an epoxy resin and an acrylic resin as a second component.

Description

[0001] The present invention relates to a hard coating film comprising a resin composition for hard coating and a cured product thereof as a coating layer (Composition For Hard Coating and Hard Coating Film Including Cured Product of The Same As The Coating Layer)

The present invention relates to a hard coating film comprising a resin composition for hard coating and a cured product thereof as a coating layer.

In general, glass has been used extensively as a material for important commercial products including optical functional products such as windows for various electronic products, touch screens for computers, lenses, automobile sunroofs, optical screens, light guide plates and LED front plates. However, glass is heavy, fragile, and has a defect rate which is considerably high at the time of processing a product. Therefore, there is a wide variety of materials that can overcome the drawbacks of glass.

Under such circumstances, the transparent polymer film has been widely used as a core material in the optical and transparent display industry, and is emerging as a substitute for glass in the display industry due to its light weight and ease of processing. However, since the polymer film has a lower surface hardness than that of the glass and thus has a disadvantage that the abrasion resistance is insufficient, a hard coating technique for improving the surface hardness of the polymer film, that is, hard coating technology is considered as an important issue.

The materials used for the hard coating are largely divided into organic, inorganic, and inorganic composite materials. Organic materials have the advantages of flexibility and moldability due to the characteristics of organic materials, but they have a disadvantage of low surface hardness. It has the advantages of hardness and transparency, but has the disadvantage of poor flexibility and moldability. As a result, organic and inorganic composite materials having both the merits of both materials are now in the spotlight and many studies have been carried out. However, the merits of both materials are insufficient yet.

On the other hand, there is a light or thermosetting coating agent as one of commonly used coating agents for hard coating. The photocurable coating agent can be cured in a short time and can be cured at room temperature, and is used as a surface protective coating for various plastic products. In order for such a coating to be usefully used for optical purposes, it should have good adhesion with a film along with hardness, and should not have a curl phenomenon or a rainbow phenomenon. In particular, the curl phenomenon can be a serious disadvantage in the roll-to-roll process, which is a mass production process, and is a particularly demanded property because it may cause problems in future durability even when it is provided as a product. In addition, the display industry is shifting to the flexible display era, which requires hard-coated films with excellent flexibility.

As a prior art related to optical or thermosetting coatings applied to optical products, Korean Patent Laid-Open Publication No. 2010-0041992 discloses a hard hard coating film composition comprising an ultraviolet curable polyurethane acrylate oligomer. This patent minimizes the curling phenomenon and prevents rainbow phenomenon due to optical interference, but fails to overcome the limit of low surface hardness as a hard coating film.

In addition, International Publication No. WO2013-187699 proposes a high hardness siloxane resin composition containing an alicyclic epoxy group, a process for producing the same, and an optical film comprising the cured product. Although the prior art has achieved a high hardness of 9 H, there is still a problem that the weatherability due to the use of a single monomer and the use of a cationic initiator may be a problem and curling may occur.

If the surface hardness of the hard coat layer is improved by forming a dense network between the molecules, the shrinkability increases and the flexibility becomes poor. In addition, the problem of curling and cracking occurs, and when the curl and crack are removed, It is difficult to overcome the problem. Therefore, the development of a high-hardness coating material having excellent flexibility, curl-free and easy processing is also an urgent necessity for wider use of the polymer film.

Accordingly, the present invention provides a hard resin composition for hard coating comprising an epoxy or acrylic resin and a siloxane resin combined with a metal element, and further comprising a cured product of the resin composition as a coating layer to provide a hard resin having excellent hardness, And to provide a coating film.

A first preferred embodiment of the present invention for solving the above-mentioned problems is a siloxane resin in which a alkoxysilane represented by the following Chemical Formula 1 and an alkoxy metal compound represented by the following Chemical Formula 2 are chemically bonded to each other as a first component; And at least one of an epoxy resin and an acrylic resin as a second component.

???????? R ¹ _n Si (OR ² ) _{4 -n} ????? (1)

M (OR < ³ &gt;) m

Wherein R ¹ is a linear C ₁ to C ₃ alkyl group containing an alicyclic epoxy group, R ² is a linear or branched C ₁ to C ₄ alkyl group, and R ³ is a linear or branched C ₁ to C ₄ alkyl group. M is one or more metal elements selected from the group consisting of aluminum, titanium and zinc, n is an integer of 1 to 3, and m is an integer of 2 to 4.

In addition, the present invention relates to a base film; And a hard coating film formed on at least one side of the base film and including a cured product of the resin composition for hard coating of the first embodiment as a hard coating layer.

According to the present invention, it is possible to provide a resin composition for hard coating that has excellent softness and smoothness while suppressing shrinkage while maintaining excellent surface hardness, and is capable of providing a flexible, hard-curled, high surface hardness A hard coating film containing a coating layer having the above properties can be provided.

Particularly, the resin composition for hard coating according to the present invention is chemically bonded to a metal within a molecule based on alicyclic epoxy and can secure an excellent surface hardness. Since an epoxy resin or an acrylic resin is included together with a siloxane resin, The shrinkage is minimized at the time of curing, so that no curling phenomenon is caused, and as the crosslinking length of the cured product is increased, the flexibility can be further effectively improved.

According to one aspect of the present invention, there is provided a positive resist composition comprising: as the first component, a siloxane resin in which an alkoxysilane represented by the following Chemical Formula 1 and an alkoxy metal compound represented by Chemical Formula 2 are chemically bonded; And as a second component, at least one of an epoxy resin and an acrylic resin.

???????? R ¹ _n Si (OR ² ) _{4 -n} ????? (1)

M (OR < ³ &gt;) m

Wherein R ¹ is a linear C ₁ to C ₃ alkyl group containing an alicyclic epoxy group, R ² is a linear or branched C ₁ to C ₄ alkyl group, and R ³ is a linear or branched C ₁ to C ₄ alkyl group. M is one or more metal elements selected from the group consisting of aluminum, titanium and zinc, n is an integer of 1 to 3, and m is an integer of 2 to 4.

More specifically, the alicyclic epoxy group contained in R ¹ of Formula 1 preferably has an alicyclic structure formed by C ₃ to C ₈ alicyclic alkyl groups. However, the C ₃ to C ₅ When cycloaliphatic be of may curling phenomenon caused by reducing intermolecular spacing, C ₇ to in the epoxy curing reaction can take place later, if the cycloaliphatic be of, improve the curing speed and the local characteristic aspects of the C ₈ C ₆ It is preferably an alicyclic epoxy group, but the present invention is not necessarily limited thereto.

Hereinafter, the first component and the second component contained in the resin composition for hard coating of the present invention will be described in more detail.

The first component

In the present invention, the epoxy-based monomer represented by the above formula (1) has a low curing shrinkage ratio, which is very significant from the standpoint of suppressing curling and ensuring excellent surface hardness. If the formula (1) is an acrylic monomer, it can exhibit a fast curing rate and a high hardness, but the contraction ratio is high and the curling probability can be increased. When the monomer of formula (1) is an isocyanate-based monomer, the flexibility is high due to its high modulus of elasticity, and thus the curling probability is low, but it can exhibit low surface hardness.

On the other hand, according to the present invention, the compound of formula (1) is an epoxy-based monomer, which has a high surface hardness relative to an isocyanate group and a curing shrinkage ratio lower than that of an acrylic group. In particular, since the compound of formula (1) of the present invention is an alicyclic epoxy-based monomer, securing the intermolecular space when cured is more advantageous than the linear epoxy-based monomer, the resin composition for hard coating of the present invention suppresses hardening shrinkage, .

Therefore, the siloxane resin of the present invention has a random-type chain structure and can have an alicyclic epoxy reactor, and the siloxane resin having various molecular weights can be densely crosslinked during photopolymerization or thermal polymerization, It becomes possible to provide a hard coated cured product.

In the present invention, the alkoxysilane represented by the general formula (1) is preferably selected from the group consisting of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane and 2- , 4-epoxycyclohexyl) ethyltripropoxysilane may be more preferable.

However, since curling due to curing shrinkage is inevitable, the first component of the present invention preferably further comprises an alkoxy metal compound represented by Formula 2 to form a chemical bond. The alkoxy metal compound is chemically bonded to the alkoxysilane, and by including the metal element in the molecular structure, the intermolecular space can be further secured, thereby minimizing the curing shrinkage and drastically reducing curling.

In the formula (2), M is at least one metal element selected from the group consisting of aluminum, titanium and zinc, which is advantageous in terms of curl improvement by appropriately maintaining the intermolecular distance, and m is a range suitable for coating the molecular weight Is preferably an integer of 2 to 4

In the present invention, the alkoxy metal compound is contained in an amount of 0.2 to 5.0 mol% based on the total molar amount of the alkoxysilane and the alkoxy metal compound to form a chemical bond, thereby ensuring ease of processing, May be preferred. If the amount of the alkoxy metal compound is less than the above range, the curl suppressing effect may be insignificant. If the reaction temperature is lowered or the polymerization is stopped within a short time, addition of up to 5.0 mol% metal compound is possible. However, when it is contained in an amount exceeding 5.0 mol%, the gelation rapidly proceeds, and the viscosity of the resin is likely to rise at a high rate, and the processability may be significantly lowered due to the strong solvent resistance, May not be large. It is more preferable that the alkoxy metal compound is contained in an amount of 0.2 mol% to 3.0 mol%.

However, in the present invention, the first component may further include an alkoxysilane represented by the following Chemical Formula 3 to form a chemical bond.

???????? Si (OR ³ ) _x

Wherein R ³ is a C ₁ to C ₄ linear or branched alkyl group, and x is an integer of 2 to 4.

The alkoxysilane represented by the formula (3) has a silane Q structure in the molecular structure, that is, a chemical bond structure such as the following <Formula 1> in which Si has no alkoxy functional group, whereby an excellent hardness can be secured. That is, when the Q structure found in the molecular structure of the glass is included in the molecular structure, the resin composition of the present invention can achieve hardness similar to that of glass upon curing.

<Structure 1>

At this time, in the present invention, the alkoxysilane represented by Formula 1 and the alkoxysilane represented by Formula 3 are preferably in a molar ratio of 99: 1 to 20:80, more preferably 85:15 to 45:55 It is easy to prevent gelation during polymerization while maintaining high hardness. When the compound of the formula (1) is used together with the compound of the formula (3), the surface hardness is more advantageous. However, when the compound of the formula (3) is present in the above range, gelation may occur during polymerization.

When the alkoxysilane represented by Formula 2 is further included, the amount of the alkoxysilane represented by Formula 2 is preferably 0.2 to 5.0 moles per 100 moles of the total of the alkoxysilane represented by Formula 1 and the alkoxysilane represented by Formula 3 % Is more preferable for synthesis control.

The siloxane resin thus produced preferably has a weight average molecular weight of 5,000 to 22,000 and a polydispersion index (PDI) of 1.5 to 3.1 when the resin does not include the formula 3, A weight average molecular weight of 3000 to 50000, and a polydispersion index (PDI) of 1.5 to 7.0.

In the present invention, the molecular weight and molecular weight distribution (PDI, Mw / Mn) were determined by polystyrene conversion weight average molecular weight (Mw) and number average molecular weight (Mn) by gel permeation chromatography (GPC) . More specifically, 20 μl of the solution was dissolved in tetrahydrofuran so as to have a concentration of 1% of the polymer to be measured, and the solution was introduced at a flow rate of 1.0 mL / min and analyzed at 30 ° C. In addition, two columns of Waters Styragel HR3 were connected in series, and the detector was measured at 40 占 폚 using an RI detector (Waters, 2414). Further, the measured weight average molecular weight was divided by the number average molecular weight to calculate PDI (molecular weight distribution diagram).

In the present invention, the siloxane resin forming reaction may proceed at room temperature, but may be stirred at 50 ° C to 120 ° C for 1 hour to 120 hours to promote the reaction. As a catalyst for carrying out the hydrolysis and condensation reaction during the reaction, an acid catalyst such as hydrochloric acid, acetic acid, hydrogen fluoride, nitric acid, and sulfuric acid iodic acid, a base such as ammonia, potassium hydroxide, sodium hydroxide, barium hydroxide, imidazole A catalyst, and an amberite may be used. These catalysts may be used alone or in combination. The amount of the catalyst is not particularly limited, but 0.0001 to about 10 parts by weight based on 100 parts by weight of the siloxane resin may be added.

When the hydrolysis and condensation reaction proceeds, alcohol as a by-product is produced. By eliminating it, the reverse reaction can be reduced and the reaction can proceed more quickly, and the reaction rate can be controlled through the reaction. Since the siloxane resin thus synthesized by the condensation reaction secures an intermolecular space at the time of crosslinking, curling due to curing shrinkage can be prevented, and it is possible to realize high surface hardness by crosslinking and metal elements.

The second component

On the other hand, the hard coat resin composition of the present invention comprises at least one of an epoxy resin and an acrylic resin as a second component. Here, the second component may be a monomer or an oligomer containing at least one functional group selected from the group consisting of an epoxy group, an oxetane group, an acrylate group, a methacrylate group, a urethane acrylate group and an ethylene oxide (EO) addition type acrylate group .

In the present invention, when the second component is contained, a siloxane resin is bonded to a monomer or a siloxane resin and oligomers are formed, and as the linear structure is longer, a siloxane resin is expressed in comparison with the case where the second component is not added The intermolecular spacing by the monomer or oligomer can be enlarged while maintaining the hardness, and the flexibility of the cured film can be further increased.

In the present invention, the epoxy resin may be at least one selected from the group consisting of glycidyl type epoxy resins, alicyclic epoxy resins and oxetane resins. The glycidyl type epoxy resin may be a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type epoxy resin, a naphthalene type epoxy resin or a hydrogenated product thereof; An epoxy resin having a dicyclopentadiene skeleton; An epoxy resin having a triglycidyl isocyanurate skeleton; An epoxy resin having a cardo skeleton; And an epoxy resin having a polysiloxane structure; Lt; / RTI &gt;

In addition, the alicyclic epoxy resin can be produced by reacting 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexanecarboxylate, 1,2,8,9-diepoxy limonene and? -Caprolactone oligomer at both ends Epoxycyclohexylmethane and 3,4-epoxycyclohexanecarboxylic acid, respectively, or an epoxy resin having a hydrogenated bisphenol A skeleton. The oxetane resin may be an oxetane resin having a hydroxy structure , An ether-based oxetane resin, or an oxetane resin having a methoxymethylbenzene structure.

In the present invention, the acrylic resin is specifically exemplified by bisphenol-A ethylene oxide diacrylate, bisphenol-A ethylene oxide dimethacrylate, bisphenol-A ethoxylate diacrylate, bisphenol-A ethoxylate Diacrylate, bisphenol-A polyethoxylate diacrylate, bisphenol-A diacrylate, bisphenol-S diacrylate, dicyclopentadienyl diacrylate, pentaerythritol triacrylate, tris Hydroxyethyl isocyanurate triacrylate, pentaerythritol tetraacrylate, bisphenol-A dimethacrylate, bisphenol-S dimethacrylate, dicyclopentadienyl dimethacrylate, pentaerythritol trimethacrylate Tris (2-hydroxyethyl) isocyanurate trimethacrylate, and pentaerythritol And tetramethacrylate. A commercially available acrylic resin may also be used.

In the present invention, the epoxy resin or the acrylic resin is preferably used alone or in combination of two or more. However, the compatibility between the resins used in combination may be lowered, resulting in lower uniformity of the coating film. Therefore, it may be more preferable to use them alone or in combination of three or less.

The first component and the second component described above are preferably contained in the resin composition for hard coating of the present invention in a mixing ratio of 9: 1 to 6: 4 by weight. When the above-mentioned siloxane resin is used in an excess ratio, it is excellent in hardness, abrasion resistance, and heat resistance. However, since the flexibility is insufficient, cracking may occur in a process such as cutting after hard coating, and an epoxy resin or an acrylic resin is used in excess ratio It is impossible to ensure the hardness, which is the physical property necessary for the hard coat layer.

In addition, the resin composition for hard coating of the present invention may further include an initiator for the polymerization of the siloxane resin in addition to the first component and the second component. For example, a photopolymerization initiator such as an organic metal salt, A thermal polymerization initiator may be used, and a cationic polymerization agent may be included. However, the addition amount of the initiator may be about 0.5 to 5 parts by weight based on 100 parts by weight of the resin composition. When the content of the hard coat layer is less than 0.5 parts by weight, hardening time of the hard coat layer to obtain sufficient hardness is increased to decrease the efficiency. When the amount of the hard coat layer exceeds 5 parts by weight, the yellow coatability of the hard coat layer is increased, have.

In addition, the resin composition for hard coating of the present invention may contain at least one member selected from the group consisting of surfactants, antioxidants and leveling agents, So that the workability is further facilitated and an organic solvent can be further added to adjust the thickness of the coating film.

The amount of the organic solvent to be added is not particularly limited and examples of usable organic solvents include ketones such as acetone, methyl ethyl ketone, methyl butyl ketone and cyclohexanone, cellosolves such as methyl cellosolve and butyl cellosolve, Or alcohols such as ethers such as ethyl ether and dioxane, isobutyl alcohol, isopropyl alcohol, butanol and methanol, halogenated hydrocarbons such as dichloromethane, chloroform and trichlorethylene, and halogenated hydrocarbons such as n-hexane, And solvents composed of hydrocarbons and the like.

Further, the present invention relates to a base film; And a coating layer laminated on at least one side of the base film and cured by hardening the resin composition for hard coating, whereby the hard coating film according to the present invention has hardness, Physical properties such as flexibility, chemical resistance and abrasion resistance are excellent, and phenomena such as curling which occurs during manufacturing and heating treatment, cracking and peeling due to bending during processing can be prevented. More specifically, the hard coating film of the present invention has a minimum curvature radius of the film of 2 mm to 6 mm in which cracks are not generated in the coating layer when the coating layer is formed in a direction opposite to the coating direction, in accordance with ASTM D3363 measurement standard, 4H to 9H have.

In the present invention, it is possible to further perform a process of making the surface uniform by a separate heat treatment before photopolymerization or thermal polymerization curing. Such additional heat treatment can further improve the hardness of the hard coating layer. In this case, in the case of photopolymerization, the heat treatment may be performed at a temperature of 40 ° C or more and about 200 ° C or less for 2 minutes to 60 minutes depending on the substrate, and in the case of thermal polymerization, But it is not limited thereto. Further, since the photo-polymerization heat treatment is 50mJ / cm ² or more 20,000mJ / cm ² or less, more preferably 200mJ / cm ² more than 5,000mJ / cm ² It may be advantageous in terms of ensuring sufficient hardness and further suppressing yellowing.

Examples of the method of applying the hard coating resin composition to a substrate include spraying, dip coating, spin coating, die coating, comma coating, screen coating, inkjet printing, pad printing, knife coating, kiss coating, bar coating and gravure coating The thickness of the hard coating layer formed of the hard coating resin composition can be easily controlled according to the kind of the base material and the application. In the present invention, it is 2 to 60 탆, preferably 10 to 30 탆 It is possible to secure both the hardness and the bendability of the hard coating film at a thickness of 占 퐉.

Although not limited thereto, in the present invention, the base film may be a polyethylene sulfonate (PES) film, a polyethylene terephthalate (PET) film, a polycarbonate (PC) film, a polymethylmethacrylate (PMMA) film, , Manufactured by BF Goodrich Co., USA) and a polyimide (PI) film may be laminated alone or in combination of two or more thereof.

In addition, the resin composition for hard coating of the present invention may be applied to inorganic substrates such as glass, quartz, glass wafers, and silicon wafers to form hard coating layers, depending on the purpose.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are for the purpose of illustrating the present invention more specifically, and the present invention is not limited thereto.

Polymerization Example  One.

The mixture was mixed with KBN-303 (Shinetsu), Titanium isopropoxide (Sigma-Aldrich) and H ₂ O at a ratio of 245.2 g: 1.4 g: 27.2 mL and placed in a 500 mL flask. Then 0.1 g of sodium hydroxide (Sigma-Aldrich) Was added thereto as a catalyst, and the reaction was carried out while stirring at 60 ° C for 10 hours while removing the alcohol formed by the Dean Stark apparatus to obtain a siloxane resin polymer 1.

Polymerization Example  2.

The mixture was mixed in a ratio of 241.5 g: 5.7 g: 27.2 mL of KBM-303 (Shinetsu), Titanium isopropoxide (Sigma-Aldrich) and H ₂ O and placed in a 500 mL flask. Then 0.1 g of sodium hydroxide (Sigma-Aldrich) Was added as a catalyst, and the reaction was carried out while stirring at 60 ° C for 10 hours while removing the alcohol produced by the Dean Stark apparatus to obtain siloxane resin polymer 2.

Polymerization Example  3.

The mixture was mixed in a ratio of 234.1 g: 14.2 g: 27.2 mL of KBM-303 (Shinetsu), Titanium isopropoxide (Sigma-Aldrich), and H ₂ O and placed in a 500 mL flask. Was added as a catalyst, and the reaction was carried out while stirring at 60 ° C for 10 hours while removing the alcohol formed by the Deanstark apparatus, thereby obtaining a siloxane resin polymer 3.

Polymerization Example  4.

259.8 mL: 1.62 g: 27.2 mL of KBM-303 (Shinetsu), aluminum ethoxide (Sigma-Aldrich) and H ₂ O were mixed and placed in a 500 mL flask. Then, 0.1 g of sodium hydroxide was added as a catalyst to obtain 60 The reaction was carried out while removing the alcohol produced by the Dean Stark apparatus, and siloxane resin polymer 4 was obtained.

compare Polymerization Example  One.

KBM-303 (Shinetsu社), the H ₂ O 246.4g: stirred after mixed at a rate of 27.2mL placed in 500mL flasks, 60 ℃ by the addition of sodium (Sigma-Aldrich社) 0.1g hydroxide as a catalyst for 10 hours And the reaction was carried out while removing the alcohol produced by the Dean Stark apparatus to obtain a siloxane resin polymer 5.

compare Polymerization Example  2.

The mixture was mixed with KBM-303 (Shinetsu), Titanium isopropoxide (Sigma-Aldrich) and H ₂ O at a ratio of 231.6 g: 17.1 g: 27.2 mL, and the mixture was added to a 500 mL flask. Was added as a catalyst, and the reaction was carried out while stirring at 60 ° C for 10 hours while removing the alcohol formed by the Deanstark apparatus, thereby obtaining a siloxane resin polymer 3.

The contents of Polymerization Examples 1 to 4 and Comparative Polymerization Polymers 1 to 2 are summarized as follows.

division Alkoxy metal compound Weight average molecular weight Polydispersity index Polymerization Example 1 Titanium isopropoxide 0.5 mol% 5,800 1.8 Polymerization Example 2 Titanium isopropoxide 2 mol% 8,200 2.2 Polymerization Example 3 Titanium isopropoxide 5 mol% 20,500 2.8 Polymerization Example 4 Aluminum ethoxide 1 mol% 19,750 2.1 Comparative Polymerization Example 1 unused 8,700 1.7 Comparative Polymerization Example 2 Titanium isopropoxide 6 mol% Gelled and not measurable

Example  One.

(Manufactured by Toagosei Co., Ltd., product name: OXT221) and cycloalipathic epoxide (manufactured by Dai-eller, product name: Celloxide2021P) were mixed at a weight ratio of 1: (Siloxane resin = 3) at a weight ratio of 3: 1 with the prepared siloxane resin. Based on the total weight of the mixed mixture, 40% by weight of methyl ethyl ketone as a diluting solvent, 1% by weight of triarylsulfonium hexafluoroantimonate (Sigma-Aldrich) as a photoinitiator, a silicone leveling agent : BYK, product name: BYK-333), and the mixture was stirred for 1 hour using a stirrer to prepare a hardcoat resin composition.

Example  2.

(Manufactured by TOAGOSEI Co., Ltd., product name: OXT221) and cycloalipathic epoxide (manufactured by Dai-eller, product name: Celloxide2021P) were mixed at a weight ratio of 1: (Siloxane resin = 9) at a weight ratio of 9: 1 with the prepared siloxane resin. Then, a hard coating resin composition was prepared in the same manner as in Example 1 above.

Example  3.

(Manufactured by TOAGOSEI Co., Ltd., product name: OXT221) and cycloalipathic epoxide (manufactured by Dai-eller, product name: Celloxide2021P) were mixed at a weight ratio of 1: (Siloxane resin = 3) at a weight ratio of 3: 1 with the prepared siloxane resin. Then, a hard coating resin composition was prepared in the same manner as in Example 1 above.

Example  4.

(Manufactured by TOAGOSEI Co., Ltd., product name: OXT221) and cycloalipathic epoxide (manufactured by Dai-eller, product name: Celloxide2021P) were mixed at a weight ratio of 1: (Siloxane resin = 3) at a weight ratio of 3: 2 with the prepared siloxane resin. Then, a hard coating resin composition was prepared in the same manner as in Example 1 above.

Example  5.

(Manufactured by Mitsubishi Chemical Corporation, product name: PE110) and bisphenol A-type EO-added diacrylate (manufacturer: Mitsunobu Co., Ltd., product name: M2100) were mixed at a weight ratio of 1: (Siloxane resin = 3) at a weight ratio of 3: 1 with the prepared siloxane resin. Based on the total weight of the mixed mixture, 40% by weight of methyl ethyl ketone as a diluting solvent, 0.67% by weight of triarylsulfonium hexafluoroantimonate (Sigma-Aldrich) as a photoinitiator, 1-hydroxycyclohexylphenyl 0.33% by weight of a ketone (manufactured by BASF, trade name: Irgacure 184) and 0.4% by weight of a silicone leveling agent (BYK, product name: BYK-333) as an additive were added and stirred for 1 hour using a stirrer to obtain a hard coating resin A composition was prepared.

Example  6.

(Manufactured by TOAGOSEI Co., Ltd., product name: OXT221) and cycloaliphatic epoxide (manufactured by Dai-Celser, product name: Celloxide2021P) were mixed at a weight ratio of 1: (Siloxane resin = 3) at a weight ratio of 3: 1 with the prepared siloxane resin. Then, a hard coating resin composition was prepared in the same manner as in Example 1 above.

Example  7.

(Manufactured by TOAGOSEI Co., Ltd., product name: OXT221) and cycloalipathic epoxide (manufactured by Dai-eller, product name: Celloxide2021P) were mixed at a weight ratio of 1: (Siloxane resin = 3) at a weight ratio of 3: 1 with the prepared siloxane resin. Then, a hard coating resin composition was prepared in the same manner as in Example 1 above.

Comparative Example  One.

Based on the weight of the siloxane resin prepared in Polymerization Example 2, 40% by weight of methyl ethyl ketone as a diluting solvent, 1% by weight of triarylsulfonium hexafluoroantimonate (Sigma-Aldrich) as a photoinitiator, , 0.4 wt% of a silicon leveling agent (BYK, product name: BYK-333) was added to the mixture, and the mixture was stirred for 1 hour using a stirrer to prepare a hard coating resin composition.

Comparative Example  2.

(Manufactured by TOAGOSEI Co., Ltd., product name: OXT221) and cycloalipathic epoxide (manufactured by Dai-eller, product name: Celloxide2021P) were mixed at a weight ratio of 1: And the siloxane resin was mixed at a weight ratio of 1: 1. Then, a hard coating resin composition was prepared in the same manner as in Example 1 above.

Comparative Example  3.

Based on the weight of the siloxane resin prepared in Comparative Polymerization Example 1, 40% by weight of methyl ethyl ketone as a diluting solvent, 1% by weight of triarylsulfonium hexafluoroantimonate (Sigma-Aldrich) as a photoinitiator, 0.4 wt% of a silicone leveling agent (BYK, product name: BYK-333) was added as an additive, and the mixture was stirred for 1 hour using a stirrer to prepare a hardcoat resin composition.

Comparative Example  4.

(Product name: Celloxide 2021P) were mixed at a weight ratio of 1: 1, and Comparative Ex. Polymerization Example 1 (manufactured by Toagosei Co., Ltd., trade name: OXT221) and cycloaliphatic epoxide Were mixed at a weight ratio of 3: 1 with the siloxane resin prepared in Example 1. Then, a hard coating resin composition was prepared in the same manner as in Example 1 above.

.

The thus prepared resin compositions of Examples 1 to 7 and Comparative Examples 1 to 4 were coated on one side of a polyethylene terephthalate film (manufacturer: Kolon, product name: HP34P) having a thickness of 75 mu m as a base, Dried for 30 minutes, irradiated with 1,000 mJ / cm 2 at an illuminance of 80 mW / cm 2 in the direction of applying the hard coating composition with an ultraviolet ray irradiation apparatus, and then heat-treated at 85 ° C. for 24 hours to obtain 85 μm and 100 μm thick Were prepared.

Then, the obtained hard coating film was subjected to the following physical property evaluation.

(1) Surface hardness: The pencil hardness was measured at a rate of 180 mm / min under a load of 750 gf according to ASTM D3363 using a pencil hardness tester manufactured by IMOTO, Japan.

(2) Flexibility: The coating layer was turned outward and wound on a rod having a radius interval of 1 mm to confirm a minimum radius at which cracks did not occur on the coated surface.

(3) Curl generation: When the coated film was cut into a plane of 100 mm x 100 mm, one side of each corner was measured as the maximum distance from the plane.

Film thickness: 85 탆 Film thickness: 100 탆 Pencil hardness Flexibility curl Pencil hardness Flexibility curl Example 1 4H Good 3mm radius 0cm 6H Good 6mm radius 0cm Example 2 4H Good 3mm radius 0cm 6H Good 6mm radius 0cm Example 3 4H Good 2mm radius 0cm 6H Radius 5mm Good 0cm Example 4 4H Good 2mm radius 0cm 6H Radius 5mm Good 0cm Example 5 4H Good 2mm radius 0cm 6H Radius 5mm Good 0cm Example 6 4H Good 2mm radius 0cm 6H Good 4mm radius 0cm Example 7 4H Good 2mm radius 0cm 6H Radius 5mm Good 0cm Comparative Example 1 4H Good 6mm radius 0.2cm 6H Good 12mm radius 0.4cm Comparative Example 2 H Good 2mm radius 0.2cm 3H Radius 5mm Good 0.5cm Comparative Example 3 3H Good 12mm radius 2.5cm 5H Good radius 22mm 5.2cm Comparative Example 4 3H Good 8mm radius 1.5cm 5H Good 15mm radius 4.5cm

From the results shown in the above Table 2, it can be seen that the hard coating films of Examples 1 to 7 exhibit excellent results in both pencil hardness, flexibility and curl characteristics, and even when rolled in a rod having a radius of 6 mm or less, .

On the contrary, when the coating layer was formed only from the siloxane resin prepared by the polymerization example, the flexibility was remarkably decreased as in Comparative Example 1, and in Comparative Example 2 in which the ratio of the siloxane resin was decreased, it was confirmed that the surface hardness was not secured . When the siloxane resin prepared in Comparative Polymerization Example 1 was used, the metal content in the siloxane was insignificant as in Comparative Examples 3 and 4, and it was confirmed that curling was not improved when the hard coating layer was formed.

Therefore, it has been confirmed through experimentation that the hard coating film produced using the hard coating resin composition of the present invention is excellent in strength, bending property and curling property, and thus can be applied as a display protective film.

Claims (11)

A siloxane resin in which an alkoxysilane represented by the following formula (1) and an alkoxy metal compound represented by the following formula (2) are chemically bonded as a first component; And
A resin composition for hard coating comprising at least one of an epoxy resin and an acrylic resin as a second component:
???????? R ¹ _n Si (OR ² ) _{4 -n} ????? (1)
M (OR < ³ &gt;) m
Wherein R ¹ is a linear C ₁ to C ₃ alkyl group containing an alicyclic epoxy group, R ² is a linear or branched C ₁ to C ₄ alkyl group, and R ³ is a linear or branched C ₁ to C ₄ alkyl group. M is one or more metal elements selected from the group consisting of aluminum, titanium and zinc, n is an integer of 1 to 3, and m is an integer of 2 to 4.
The resin composition for hard coating according to claim 1, wherein the first component and the second component are mixed in a weight ratio of 9: 1 to 6: 4.
2. The hard coating according to claim 1, wherein the alkoxymethyl compound represented by the general formula (2) in the first component is contained in an amount of 0.2 to 5.0 mol% based on the total moles of the alkoxysilane and the alkoxy metal compound, Resin composition.
The resin composition for hard coating according to claim 1, wherein the siloxane resin as the first component has a weight average molecular weight of 5,000 to 22,000 and a polydispersion index (PDI) of 1.5 to 3.1.
The resin composition for hard coating according to claim 1, wherein the first component further comprises an alkoxysilane represented by the following formula (3) to form a chemical bond.
???????? Si (OR ³ ) _x
Wherein R ³ is a C ₁ to C ₄ linear or branched alkyl group, and x is an integer of 2 to 4.
[6] The method of claim 5, wherein the alkoxysilane represented by Formula 1 and the alkoxysilane represented by Formula 3 have a molar ratio of 99: 1 to 20:80,
Wherein the alkoxy metal compound represented by Formula 2 is contained in an amount of 0.2 to 5.0 mol% based on 100 mol of the total of the alkoxysilane represented by Formula 1 and the alkoxysilane represented by Formula 3. [ / RTI &gt;
The resin composition for hard coating according to claim 5, wherein the siloxane resin has a weight average molecular weight of 3,000 to 50,000 and a polydispersion index (PDI) of 1.5 to 7.0.
The method according to claim 1, wherein the second component is a monomer containing at least one functional group selected from the group consisting of an epoxy group, an oxetane group, an acrylate group, a methacrylate group, a urethane acrylate group and an ethylene oxide (EO) Wherein the resin composition is an oligomer.
A base film; And a hard coating film formed on at least one side of the base film, wherein the hard coating film comprises a cured product of the resin composition according to any one of claims 1 to 8 as a hard coating layer.
10. The hard coating film according to claim 9, wherein the hard coating film has a surface hardness in a direction in which the coating layer is formed is from 4H to 9H according to ASTM D3363 measurement standard.
The hard coating film according to claim 9, wherein the hard coating film has a minimum curvature radius of the film of 2 to 6 mm, in which no crack is generated in the coating layer when the coating layer is bent in the opposite direction in which the coating layer is formed.