WO2016108676A1 - Resin composition for hard coating, and hard-coating film comprising cured form of same as coating layer - Google Patents

Abstract

The present invention relates to a resin composition for a hard coating, the composition comprising a siloxane resin that is chemically bonded by means of compounds comprising a compound of an alkoxy metal and alkoxysilane, and the invention relates to a hard-coating film comprising a hard-coating layer formed from the resin composition for a hard coating.

Description

Hard coating film comprising a resin composition for hard coating and a cured product thereof as a 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 uniquely used as a material for important commercial products including optical functional products such as windows of various electronic products, touch screens for computers, lenses, automotive sunroofs, optical screens, light guide plates, and LED front panels. However, the glass is heavy, fragile, and at the same time has the disadvantage that the defect rate is very high in the processing of the product, the situation that can overcome the disadvantages of the glass has been made in many ways.

In such a situation, the transparent polymer film is widely used as a core material of the optical and transparent display industries, and in particular, due to its light weight and ease of processing, it has emerged as a substitute material for glass in the display industry. However, the polymer film has a lower surface hardness than glass, and thus has a disadvantage in that the wear resistance is insufficient. Therefore, a high hardness coating, that is, a hard coating technology for improving the surface hardness of the polymer film has been considered as an important issue.

The materials used for hard coatings are largely divided into organic, inorganic and organic-inorganic composites. Organic materials have the advantages of flexibility and formability due to the characteristics of organic materials, but have the disadvantage of low surface hardness. It has the advantages of hardness and transparency, but has the disadvantage of poor flexibility and formability. As a result, organic-inorganic composite materials having both the advantages of both materials are currently in the spotlight, and much research is being conducted, but it is still insufficient to realize the advantages of both materials.

On the other hand, one of the coatings generally used for hard coating is a light or thermosetting coating agent. Photocurable coatings can be cured in a short time, as well as room temperature can be used as a surface protective coating of various plastic products. In order for this coating to be usefully applied for the optical, the hardness and the adhesion to the film should be excellent, and there should be no curl and rainbow. In particular, the curl phenomenon may act as a big disadvantage in the roll-to-roll process, which is a mass-produced product, and even when provided as a product, it may cause a problem in the future, which is a particularly required physical property. In addition, the display industry is moving into the era of flexible displays, which requires a flexible hard coating film.

As a related art related to an optical or heat curable coating agent applied to an optical product, Korean Patent Laid-Open Publication No. 2010-0041992 provides a hard coating film composition including a hardening polyurethane acrylate oligomer. The patent minimizes curling and prevents rainbow phenomenon due to light interference, but does not overcome the limitation of low surface hardness as a hard coating film.

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

As such, when the surface hardness of the hard coating layer is improved by forming a dense intermolecular network, the shrinkage property increases and the flexibility decreases, the problem of curling and cracking occurs, and the increase of flexibility and the elimination of curling and cracking limits the surface hardness. The problem arises that it does not overcome. Therefore, the development of a high hardness coating material having excellent flexibility, no curl, and ease of processing is urgently needed for wider application of the polymer film.

Therefore, the present invention includes an alkoxy silane containing an alicyclic epoxy, which is an organic-inorganic complex, and a siloxane resin in which an alkoxy metal is chemically bonded, thereby securing a space in the molecular structure, thereby suppressing shrinkage while maintaining surface hardness and curling. It is to provide a resin composition for hard coating without.

In addition, the alkoxy silane and the alkoxy metal is added to the alkoxy silane containing a Q structure of the silane, such as TEOS (Tetraethyl orthosilicate) is further added to provide a resin composition for hard coating comprising a siloxane resin forming a bonding structure, or the siloxane To provide a resin composition for hard coating comprising an epoxy to acrylic resin with a resin

Furthermore, by including the cured product of the resin composition as a coating layer, there is no curl phenomenon, to provide a hard coating film excellent in high surface hardness, adhesion, wear resistance and flex resistance.

A first preferred embodiment of the present invention for solving the above problems is a hard coating comprising a siloxane resin chemically bonded by compounds comprising an alkoxy silane represented by the following formula (1) and an alkoxy metal compound represented by the following formula (2) Resin composition.

<Formula 1> R ¹ _n Si (OR ² ) _4-n

<Formula 2> M (OR ³ ) _m

In this case, in Formulas 1 to 2, R ¹ is an alkyl group of C ₁ to C ₃ including an alicyclic epoxy group, R ² is an alkyl group of linear or branched C ₁ to C ₄ , R ³ is a linear or branched An alkyl group of C ₁ to C ₄ . In addition, M is at least one metal element selected from the group consisting of aluminum, titanium and zinc, n is an integer of 1 to 3, m is an integer of 2 to 4.

In addition, a second preferred embodiment of the present invention for solving the above problems is an alkoxy silane represented by the formula (1) in the first embodiment, the alkoxy silane represented by the following formula (3) to the alkoxy metal compound represented by the formula (2) It is a resin composition for hard coatings containing the siloxane resin chemically bonded by the containing compound.

<Formula 3> Si (OR ³ ) ₄

However, in Formula 3, R ³ is a C ₁ to C ₄ linear or branched alkyl group.

In addition, according to a third preferred embodiment of the present invention for solving the above problems, the siloxane resin of the first embodiment or the second embodiment is a first component, and at least one of an epoxy resin and an acrylic resin is further used as the second component. It is a resin composition for hard coatings containing.

Furthermore, a fourth preferred embodiment of the present invention for solving the above problems is a base film; And a hard coating layer formed on at least one surface of the base film by curing the resin composition for hard coating of the first to third embodiments.

According to the present invention, it is possible to provide a resin composition for hard coating without curling by maintaining shrinkage while maintaining excellent surface hardness, and using the resin composition, a hard coating film including a coating layer having no high surface hardness and no curling phenomenon. Can be provided. In particular, the resin composition for hard coating of the present invention is a metal bond by the alkoxy metal in the molecule based on the alicyclic epoxy to ensure the intermolecular space, thereby minimizing shrinkage during curing, thereby excellent surface hardness When it is secured and formed into a coating layer, it is possible to effectively suppress curl generation of the hard coat film.

In addition, according to the present invention by introducing alkoxy silane having a Q structure of the silane and an alkoxy metal compound together in the alkoxy silane having an alicyclic epoxy group, the resin composition for hard coating that can realize surface hardness during curing and minimal curl generation Can be provided. Above all, the resin composition for hard coating of the present invention using the alkoxy silane having the Q structure of silane includes the Q structure of the silane in the molecular structure, so that the crosslinking becomes dense during the polymerization reaction of the alicyclic organic material, thereby ensuring excellent surface hardness. It can be formed into a cured product on the film surface to provide a hard coating film of excellent performance.

Furthermore, the siloxane resin chemically bonded by the alkoxy silane which has an alicyclic epoxy group, the compound containing an alkoxy metal compound, or the alkoxy silane which has an alicyclic epoxy group, the alkoxy silane which has Q structure of a silane, and the compound containing an alkoxy metal compound, By further including an epoxy to acrylic resin together, the adhesion and the flex resistance can be further improved.

1 is a reaction scheme showing a synthesis mechanism by a sol-gel (Sol-Gel) method of the siloxane resin contained in the resin composition for hard coating according to the first embodiment of the present invention.

The present invention provides a resin composition for hard coating comprising a siloxane resin chemically bonded by alkoxy silane containing an alicyclic epoxy group and compounds containing an alkoxy metal compound.

In the present invention, the alkoxy silane may be represented by the following Chemical Formula 1, and according to a more preferred embodiment of the present invention, the alkoxy silane represented by the following Chemical Formula 1 is 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane , 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane and 2- (3,4-epoxycyclohexyl) ethyltripropoxysilane.

<Formula 1> R ¹ _n Si (OR ² ) _4-n

In Formula 1, R ¹ is a linear C ₁ to C ₃ alkyl group including an alicyclic epoxy group, R ² is a linear or branched C ₁ to C ₄ alkyl group, n is an integer of 1 to 3.

More specifically, it is preferable that the alicyclic epoxy group included in R ¹ of Formula 1 has an alicyclic structure composed of C ₃ to C ₈ alicyclic alkyl groups. However, in the case of C ₃ to C ₅ alicyclic, curling may occur due to a decrease in intermolecular spacing, and in the case of alicyclic C ₇ to C _8, the epoxy curing reaction may proceed slowly, thereby improving the curing rate or curling characteristics of C ₆ . Although it is preferable that it is an alicyclic epoxy group, this invention is not necessarily limited to this.

In the present invention, the formula (1) is an epoxy monomer is very significant in terms of having a low curing shrinkage rate and can ensure excellent surface hardness while suppressing curl generation. If the formula (1) is an acrylic monomer may exhibit a fast curing rate and high hardness, but the shrinkage rate is high, it may increase the probability of curling. In addition, if the formula (1) is an isocyanate monomer, the elastic modulus is high and excellent in flexibility and accordingly less curl generation probability, but may exhibit a low surface hardness.

On the contrary, according to the present invention, since the formula (1) is an epoxy monomer, the surface hardness is higher than that of the isocyanate group, and it has a lower curing shrinkage rate than the acryl group, thereby suppressing curl generation. In particular, since the formula (1) of the present invention is an alicyclic epoxy monomer, it is advantageous to secure an intermolecular space during curing than a linear epoxy monomer, so that the resin composition for hard coating of the present invention is more effectively prevented from curling due to cured shrinkage. Thus, the siloxane resin of the present invention is capable of densely crosslinking siloxane molecules of various molecular weights during photopolymerization or thermal polymerization, thereby providing a hard coating cured product having high hardness.

However, since curling due to curing shrinkage is an inevitable phenomenon, the present invention provides a hard coating composition for a siloxane resin chemically bonded by compounds containing an alkoxy silane and an alkoxy metal compound represented by the following Formula 2 at the same time. It is made into the main ingredient. That is, by including a structure in which the alkoxy silane and the alkoxy metal compound are combined in the molecular structure, the intermolecular space can be further secured by the metal element, and accordingly, the hard coating resin composition of the present invention minimizes hardening shrinkage to prevent curling. It can be drastically reduced.

<Formula 2> M (OR ³ ) m

In Formula 2, R ³ is a linear or branched C ₁ to C ₄ alkyl group, M is at least one metal element selected from the group consisting of aluminum, titanium and zinc, m is an integer of 2 to 4.

In the present invention, the alkoxy metal compound may be included in an amount of 0.2 mol% to 5.0 mol% based on the total moles of the alkoxy silane and the alkoxy metal compound, which may be preferable in terms of ensuring ease of processing and effectively suppressing curl generation. Can be. When the alkoxy metal compound is included in less than 0.2 mol%, the effect of suppressing curl generation may be insignificant, and when the reaction temperature is lowered or the polymerization is stopped within a short time, up to 5.0 mol% metal compound may be added. However, when contained in excess of 5.0 mol%, as the gelation progresses rapidly, the viscosity of the resin rises rapidly, and the solvent resistance may be significantly decreased due to the strong solvent resistance. May not be large. Thus, the alkoxy metal compound may be more preferably contained in 0.2 mol% to 3.0 mol%.

For reference, Figure 1 is a schematic of the reaction mechanism by the Sol-Gel method of the chemical reaction of the alkoxy silane and alkoxy metal compound of the present invention, the entire siloxane resin can be formed due to the repetition of Route 1 or Route 2 reaction have.

In the present invention, the siloxane resin formation reaction may proceed at room temperature, but may be stirred for 1 hour to 120 hours at 50 ℃ to 120 ℃ to promote the reaction. In addition, as a catalyst for the hydrolysis and condensation reaction during the reaction, an acid catalyst such as hydrochloric acid, acetic acid, hydrogen fluoride, nitric acid and iodide sulfate, base such as ammonia, potassium hydroxide, sodium hydroxide, barium hydroxide, imidazole and the like Catalysts and ion exchange resins such as Amberite may be used, and these catalysts may be used alone but may be used in combination. The amount of the catalyst is not particularly limited, but may be added in an amount of 0.0001 to about 10 parts by weight based on 100 parts by weight of the siloxane resin.

When the hydrolysis and condensation reaction proceeds, by-product alcohol is generated, and by removing this, the reverse reaction can be reduced to allow the forward reaction to proceed more quickly, and the reaction rate can be controlled through the reaction. In addition, after the reaction, the by-products can be removed by applying heat under reduced pressure.

As described above, the siloxane resin synthesized by the condensation reaction may adjust the viscosity and the curing rate by the monomers added during the reaction, thereby providing an optimum resin composition suitable for the purpose. In addition, the siloxane resin obtained through the reaction as described above can secure the intermolecular space during crosslinking, thereby preventing the curl phenomenon caused by curing shrinkage, and enables high surface hardness by crosslinking and metal elements.

Meanwhile, the siloxane resin of the present invention is not limited thereto, and may further include alkoxy silane represented by Chemical Formula 1 and an alkoxy metal represented by Chemical Formula 2, further comprising an alkoxy silane represented by Chemical Formula 3 to form a chemical bond. .

<Formula 3> Si (OR ³ ) ₄

In Formula 3, R ³ is a C ₁ to C ₄ linear or branched alkyl group.

The alkoxy silane represented by Chemical Formula 3 includes a silane Q structure in the molecular structure, that is, a chemical bonding structure such as <Formula 1> having no alkoxy functional group in Si, thereby ensuring excellent hardness. That is, by including the Q structure found in the molecular structure of the glass in the molecular structure, the resin composition of the present invention is able to realize a rigidity similar to glass at the time of curing.

<Structure 1>

At this time, the alkoxy silane represented by the formula (1) and the alkoxy silane represented by the formula (3) in the present invention preferably has 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 securing high hardness. When the compound of Formula 1 and Formula 3 are used together, it is more advantageous to improve the surface hardness, but when the compound of Formula 3 is present in excess of the above range, it may be difficult to control the polymerization due to the possibility of gelation during polymerization.

In addition, when the present invention further includes the formula (3), the alkoxy metal compound represented by the formula (2) is 0.2 mol% based on a total of 100 mol of the alkoxy silane represented by the formula (1) and the alkoxy silane represented by the formula (3) It is more preferable for the synthesis control to contain from 5.0 mol%.

When the siloxane resin prepared according to the present invention does not include Formula 3, the weight average molecular weight is 5,000 to 22,000, the polydispersity index (PDI, molecular weight distribution) is preferably 1.5 to 3.1, and includes the formula (3) In this case, the weight average molecular weight is 3000 to 50000, and the polydispersity index (PDI) is preferably 1.5 to 7.0.

In the present invention, the molecular weight and the molecular weight distribution (PDI, Mw / Mn) is obtained by gel permeation chromatography (GPC) (Waters, model name e2695) to obtain the polystyrene reduced weight average molecular weight (Mw) and number average molecular weight (Mn) This is the value applied. 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 then injected into a GPC, and flowed at a flow rate of 1.0 mL / min, and analysis was performed at 30 ° C. In addition, two columns of Waters' Styragel HR3 were connected in series, and the column was measured at 40 ° C using an RI detector (Waters, 2414) as a detector. In addition, PDI (molecular weight distribution map) was calculated by dividing the measured weight average molecular weight by the number average molecular weight.

Furthermore, the hard coating composition of this invention makes the said siloxane resin a 1st component, and contains at least one of an epoxy resin and an acrylic resin as a 2nd component. More specifically, the second component may be a monomer or oligomer including at least one functional group among 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. have.

When the second component is included in the present invention, as the bond between the siloxane resin and the monomer or the siloxane resin and the oligomer is generated, the linear structure becomes longer, and thus the siloxane resin is expressed in contrast to when the second component is not added. While maintaining the hardness as it is, the intramolecular spacing by the monomer or oligomer can be enlarged, and the flexibility of the cured film can be further increased.

In the present invention, the epoxy resin may be one or more selected from the group consisting of glycidyl-type epoxy resin, alicyclic epoxy resin and oxetane-based resin. At this time, the glycidyl epoxy resin is bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, naphthalene type epoxy resin or hydrogenated materials thereof; Epoxy resins having a dicyclopentadiene skeleton; Epoxy resins having a triglycidyl isocyanurate skeleton; Epoxy resins having a cardo skeleton; And an epoxy resin having a polysiloxane structure.

The alicyclic epoxy resin is provided at both ends of 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexanecarboxylate, 1,2,8,9-diepoxylimonene and ε-caprolactone oligomer. Each of 3,4-epoxycyclohexyl methanol and 3,4-epoxycyclohexanecarboxylic acid may be ester-bonded or an epoxy resin having a hydrogenated bisphenol A skeleton, and the oxetane-based resin may be an oxetane resin having a hydroxy structure. It may be an oxetane resin having an ether oxetane resin or methoxy methyl benzene structure.

In the present invention, the acrylic resin is specifically, for example, 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 (2-hydride Roxyethyl) isocyanurate triacrylate, pentaerythritol tetraacrylate, bisphenol-A dimethacrylate, bisphenol-S dimethacrylate, dicyclopentadienyl dimethacrylate, pentaerythritol trimethacryl Lates, tris (2-hydroxyethyl) isocyanurate trimethacrylate and pentaerythritol At least one selected from tetramethacrylate may be used, and an acrylic resin may also use a commercially available product.

In the present invention, the epoxy resin or acrylic resin is preferably used alone or used by mixing two or more kinds. However, since the compatibility between the resins used in a mixture may be lowered and the uniformity of the coating film may be lowered, it may be more preferable to use the mixture alone or in combination of three or less.

As described above, the first component and the second component described above are preferably included in a mixing ratio of 9: 1 to 6: 4 by weight in the resin composition for hard coating of the present invention. When the siloxane resin is used in an excess ratio, the hardness, abrasion resistance, and heat resistance are excellent, but there is a lack of flexibility, so cracking may occur in a process such as cutting after hard coating, and an epoxy resin or an acrylic resin is used in an excess ratio. In other words, the hard coating layer may not be able to secure hardness, which is an essential property.

On the other hand, 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 organometallic salt or an amine, imidazole, and the like. A thermal polymerization initiator can be used, and a cationic polymerizer may also be included. However, the amount of the initiator may be included in about 0.5 to 5 parts by weight based on 100 parts by weight of the total resin composition. If the content is less than 0.5 parts by weight, the curing time of the hard coating layer to increase the hardness is increased, and the efficiency is lowered. If the content is more than 5 parts by weight, the yellowness of the hard coating layer is increased, making it difficult to obtain a transparent coating layer. have.

In addition, the resin composition for hard coating of the present invention may further include one or more selected from the group consisting of surfactants, antioxidants and leveling agents, according to the special function or need, in particular, the viscosity of the siloxane resin In order to control the controllability and at the same time to further control the thickness of the coating film may be further added an organic solvent.

The addition amount of the organic solvent is not particularly limited, but examples of the organic solvent that can be used include ketones such as acetone, methyl ethyl ketone, methyl butyl ketone and cyclohexanone, or cellosolves such as methyl cellosolve and butyl cellosolve, Or ethers such as ethyl ether and dioxane, alcohols such as isobutyl alcohol, isopropyl alcohol, butanol and methanol, or halogenated hydrocarbons such as dichloromethane, chloroform and trichloroethylene, or normal hexane, benzene and toluene It may include one or more selected from a solvent consisting of hydrocarbons and the like.

Accordingly, the present invention is a base film; And it is laminated on at least one side of the base film, it can provide a hard coating film comprising a coating layer prepared by curing the resin composition for hard coating, the hard coating film according to the present invention is hardness, adhesion, bending resistance, It is excellent in physical properties such as chemical resistance and abrasion resistance, and it is possible to prevent phenomena such as curling and peeling due to bending during processing and heat treatment during manufacturing and heat treatment.

More specifically, the hard coating film of the present invention is ASTM D3363 measurement standards, 4H to 9H in the direction in which the coating layer is formed, when the alkoxy silane of formula 3 includes 100mm X 100mm area, 25 ℃ and 50% RH conditions After 24 hours at, the maximum curl value at which the edge of the film is spaced from the horizontal bottom may be 30 mm, which may be particularly suitably applied as a display protective film. In addition, when mixing up to the second component, the hard coating film may have a very good bendability such that the minimum curvature radius of the film does not cause cracks in the coating layer when the bend is formed in the opposite direction to the coating surface such that 2mm to 6mm is flexible. .

In the present invention, before the photopolymerization or thermal polymerization curing, it is possible to further perform a process to uniform the surface through a separate heat treatment, through this 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 for 2 minutes to 60 minutes at a temperature of 40 ° C. or more and about 200 ° C. or less according to the substrate, and in the case of thermal polymerization, 2 minutes at a temperature of 60 ° C. or more and about 300 ° C. or less depending on the substrate. To 60 minutes, but 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 Performing below may be advantageous in terms of ensuring sufficient hardness while more suppressing the occurrence of yellowing.

The hard coating resin composition may be applied to a substrate by 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 coating may be made by any one method, and the thickness of the hard coating layer formed of the hard coating resin composition may be easily adjusted according to the type of the substrate or the use thereof, and in the present invention, 2 to 60 μm, preferably 10 to 30. Hardness and flexibility of the hard coat film can be secured at the same thickness.

Although not necessarily limited thereto, the base film in the present invention is a polyethylene sulfonate (PES) film, polyethylene terephthalate (PET) film, polystyrene (PS), methyl methacrylate-styrene (MS), polycarbonate (PC) The organic synthetic resin film including a film, a polymethyl methacrylate (PMMA) film, a sulfin (Surlyn (manufactured by BFGoodrich, USA)), a polyimide (PI) film, and the like may be laminated alone or two or more.

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

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

[ First Example ]

Example  1-1. Photocuring  coating Cured product  Produce

227.96 mL of KBM-303 (Shinetsu), 2.96 mL of Titanium isopropoxide (Sigma-Aldrich) and 27.02 mL of H ₂ O were mixed and placed in a 500 mL flask, and 0.2 g of sodium hydroxide was added as a catalyst at 60 ° C. Stir for 24 hours. Thereafter, the resultant was filtered using a 0.45 um Teflon filter to obtain a siloxane resin covalently bonded to Titanium. The molecular weight of the resin was measured using GPC, and it was confirmed that it has a number average molecular weight of 7245, a weight average molecular weight of 20146, and a polydispersity index (PDI, M _w / M _n ) of 2.78.

Next, 3 parts by weight of IRGACURE 250 (BASF Co., Ltd.) was added as a photoinitiator to 100 parts by weight of the resin, and then coated on the surface of the colorless polyimide with varying thicknesses of 10, 20, and 30 μm, and the UV lamp having a wavelength of 315 nm was 30 It was exposed to light for a second time to prepare a hardened coating cured product.

Example  1-2. Thermosetting  coating Cured product  Produce

After the siloxane resin was obtained in the same manner as in Example 1-1, 2-ethyl-4-methylimidazole (Sigma-Aldrich) was added 2 parts by weight based on 100 parts by weight of the resin as a thermal initiator instead of the photoinitiator, and the colorless poly On the mid surface was coated with varying thicknesses of 10, 20, 30um. It was heat-treated at a temperature of 120 ° C. for 4 hours to prepare a hard coating coating.

Example  1-3. Aluminum alkoxide  adding

Example 1 except that siloxane resin having a number average molecular weight of 7027, a weight average molecular weight of 21325, and a polydispersity index of 3.03 was prepared by adding 1.62 g of aluminum ethoxide (Sigma-Aldrich) instead of 2.96 mL of titanium isopropoxide. Resin was prepared and coated in the same manner as -1 to prepare a coating cured product.

Example  1-4. Zinc alkoxide  adding

Example 1 except that 1.27 g of zinc methoxide (Sigma-Aldrich) was added instead of 2.96 mL of titanium isopropoxide to prepare a siloxane resin having a number average molecular weight of 7312, a weight average molecular weight of 20072, and a polydispersity index of 2.74. Resin was prepared and coated in the same manner as -1 to prepare a coating cured product.

Example  1-5. Titanium alkoxide  Change in content ( 0.1mol% )

Resin was prepared in the same manner as in Example 1-1, except that 0.30 mL of titanium isopropoxide (Sigma-Aldrich) was added to prepare a siloxane resin having a number average molecular weight of 7592, a weight average molecular weight of 20324, and a polydispersity index of 2.67. To prepare a coating cured product was prepared.

Example  1-6. Titanium alkoxide  ratio change ( 0.5mol% )

Resin was prepared in the same manner as in Example 1-1, except that 1.48 mL of titanium isopropoxide (Sigma-Aldrich) was added to prepare a siloxane resin having a number average molecular weight of 6985, a weight average molecular weight of 19952, and a polydispersity index of 2.85. Was prepared and coated to prepare a coating cured product.

Example  1-7. Titanium alkoxide  ratio change ( 1.5mol% )

Resin was prepared in the same manner as in Example 1-1, except that 4.44 mL of titanium isopropoxide (Sigma-Aldrich) was added to prepare a siloxane resin having a number average molecular weight of 7428, a weight average molecular weight of 20523, and a polydispersity index of 2.76. To prepare a coating cured product was prepared.

Example  1-8. Titanium alkoxide  ratio change ( 1.8mol% )

Resin was prepared in the same manner as in Example 1-1, except that 5.33 mL of titanium isopropoxide (Sigma-Aldrich) was added to prepare a siloxane resin having a number average molecular weight of 7790, a weight average molecular weight of 21338, and a polydispersity index of 2.74. To prepare a coating cured product was prepared.

Example  1-9. Titanium alkoxide  ratio change ( 2.0mol% ) And reaction time control

A siloxane resin having a number average molecular weight of 3438 weight average molecular weight of 5151 polydispersity index of 1.5 was obtained in the same manner as in Example 1-1, except that 5.92 mL of titanium isopropoxide (Sigma-Aldrich) was added and the reaction time was progressed for 5 hours. It was obtained and coated to prepare a coating cured product.

Example  1-10. Titanium alkoxide  ratio change ( 5.0mol% ) And reaction time control

A siloxane resin having a number average molecular weight of 2654 weight average molecular weight of 5600 polydispersity index 2.1 in the same manner as in Example 1-1, except that 14.80 mL of titanium isopropoxide (Sigma-Aldrich) was added and the reaction time was progressed for 2 hours. It was obtained and coated to prepare a coating cured product.

Comparative example  1-1. Photocuring  coating Cured product

A siloxane resin having a number average molecular weight of 5395, a weight average molecular weight of 15116, and a polydispersity index of 2.80 was obtained by the same method as in Example 1 except that no titanium isopropoxide was added. Thereafter, the coating cured product coated with the siloxane resin obtained through Comparative Example 1 was prepared under the same conditions as in Example 1-1.

Comparative example  1-2. Thermosetting  coating Cured product

Using the same resin as Comparative Example 1-1, using the same thermosetting coating method as in Example 2 to prepare a cured coating.

Comparative example  1-3. Titanium alkoxide  change ratio ( 5.5mol% ) And response time

Titanium isopropoxide (Sigma-Aldrich) was added to 16.28mL and the reaction time was controlled to less than 1 hour to prepare a resin in the same manner as in Example 1-1 to coat the film, but difficult to control the gelation of the resin As a result, the solubility in organic solvents was drastically degraded, which was not suitable for coating.

< First Measurement example >

Subsequently, except for Comparative Examples 1-3, which are not suitable for coating, the physical properties of the Examples 1-1 to 1-10 and Comparative Examples 1-1 to 1-2 were evaluated according to the following method. The results are shown in Table 1 below.

(1) Surface hardness: Pencil hardness was measured at 750 gf load at a speed of 180 mm / min in accordance with ASTM D3363 using a pencil hardness tester manufactured by IMOTO, Japan.

(2) Curling: When the coated film was cut into 30 cm X 21 cm and placed on a flat surface, one side of each corner was measured as the maximum value of the distance from the flat surface.

(3) Chemical resistance: After fixing the film cut to 1cm X 1cm on the slide glass with the adhesive tape (3M) with the coating surface facing upward, immersed in acetone, NMP, KOH 0.05% aqueous solution for 12 hours, then peeling off the coating layer It was determined by measuring whether or not to occur when the peeling occurs, it is judged to be good when not reflected in Table 1 below.

TABLE 1

According to the surface hardness measurement results according to the thickness, compared with Comparative Examples 1-1 and 1-2, it was confirmed that the surface hardness and curl characteristics of Examples 1-1 to 1-10 with the addition of the alkoxy metal were remarkably improved. Curing by photocuring (Example 1-1) was shown to be more advantageous for surface hardness than thermosetting (Example 1-2). On the contrary, it was confirmed that curling does not occur even at a thickness of 30 μm during thermal curing, and thermal curing may be more advantageous in terms of suppressing curl generation.

Furthermore, by contrasting the curl characteristics of Examples 1-5 to 1-10, when the amount of the addition of the alkoxy metal was further increased, it was confirmed that the intermolecular distance in the molecular structure can be secured and the curl characteristics can be further improved. . However, at the time when 2 mol% or more of the alkoxy metal content was added (Examples 1-9 and 1-10), the surface hardness and curl generation could be suppressed by reducing the reaction time, but the comparison exceeded 5.0 mol%. In the case of Example 1-3, if the reaction was stopped before gelation proceeded, sufficient reaction did not occur, or if the reaction time was minimized in consideration of the sufficient reaction, the progress of gelation could not be suppressed and the viscosity of the resin rapidly increased. Accordingly, it was confirmed that the coating is difficult.

[ 2nd Example ]

First, in the second embodiment, only the TEOS is used for the alkoxy silane represented by the general formula (3) of the present invention because TEOS is cheap and easy to obtain, and even if other alkoxy groups are used, the polymer structure has a Q structure. To be the same.

Example  2-1

KBM-303 (Shinetsu), TEOS (Sigma-Aldrich) and H ₂ O were mixed at a rate of 365.87 g: 2.50 g: 40.66 mL, placed in a 500 mL flask, 0.06 g of sodium hydroxide was added as a catalyst, and Titanium isopropoxide. 0.85 g of Sigma-Aldrich Co., Ltd. was added and stirred at 60 ° C. for 10 hours. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 5000, polydispersity index 2.0). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Example  2-2

KBM-303 (Shinetsu), TEOS (Sigma-Aldrich) and H ₂ O were mixed in a ratio of 332.61 g: 29.69 g: 41.87 mL into a 500 mL flask, 0.06 g of sodium hydroxide was added as a catalyst, and Titanium isopropoxide. (Sigma-Aldrich Co., Ltd.) was added 2.13g and stirred at 60 ℃ for 10 hours. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 10000, polydispersity index 2.2). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Example  2-3

KBM-303 (Shinetsu), TEOS (Sigma-Aldrich) and H ₂ O were mixed in a ratio of 295.66 g: 59.37 g: 43.22 mL, placed in a 500 mL flask, 0.06 g of sodium hydroxide was added as a catalyst, and Titanium isopropoxide. (Sigma-Aldrich, Inc.) was added 4.26g and stirred at 60 ° C for 10 hours. Thereafter, the resultant was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 15000, polydispersity index 3.0). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Example  2-4

KBM-303 (Shinetsu), TEOS (Sigma-Aldrich) and H ₂ O were mixed at a ratio of 184.79 g: 146.87 g: 47.28 mL, placed in a 500 mL flask, 0.06 g of sodium hydroxide was added as a catalyst, and Titanium isopropoxide. 12.79 g of Sigma-Aldrich Co., Ltd. was added and stirred at 60 ° C. for 10 hours. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 37000, polydispersity index 4.3). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Example  2-5

KBM-303 (Shinetsu), TEOS (Sigma-Aldrich) and H ₂ O were mixed in a ratio of 73.91 g: 234.37 g: 51.33 mL, placed in a 500 mL flask, 0.06 g of sodium hydroxide was added as a catalyst, and Titanium isopropoxide. (Sigma-Aldrich Co., Ltd.) 21.32g was added and stirred for 10 hours at 60 ℃ gel was difficult to control. Thereafter, the resultant was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 50000, polydispersity index 6.2). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Example  2-6

KBM-303 (Shinetsu), TEOS (Sigma-Aldrich) and H ₂ O were mixed in a ratio of 73.91 g: 234.37 g: 51.33 mL, placed in a 500 mL flask, 0.06 g of sodium hydroxide was added as a catalyst, and Titanium isopropoxide. (Sigma-Aldrich Co., Ltd.) After the addition of 21.32 g of stirring at 60 ° C. for 3 hours to prevent gelation, the siloxane resin (weight average molecular weight 3500, polydispersity index 1.8) was easily obtained without gelation. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin. Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Example  2-7

KBM-303 (Shinetsu Co., Ltd.), TEOS (Sigma-Aldrich Co., Ltd.) and H ₂ O were mixed at a ratio of 295.66 g: 53.12 g: 43.22 mL, placed in a 500 mL flask, 0.06 g of sodium hydroxide was added as a catalyst, and Titanium isopropoxide. 12.79 g of Sigma-Aldrich Co., Ltd. was added and stirred at 60 ° C. for 10 hours. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 28000, polydispersity index 3.2). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Example  2-8

KBM-303 (Shinetsu Co., Ltd.), TEOS (Sigma-Aldrich Co., Ltd.) and H ₂ O were mixed at a ratio of 295.66 g: 601.87 g: 43.22 mL, placed in a 500 mL flask, 0.06 g of sodium hydroxide was added as a catalyst, and Titanium isopropoxide. 0.85 g of Sigma-Aldrich Co., Ltd. was added and stirred at 60 ° C. for 10 hours. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 24000, polydispersity index 2.8). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Example  2-9

KBM-303 (Shinetsu Co., Ltd.), TEOS (Sigma-Aldrich Co., Ltd.) and H ₂ O were mixed at a ratio of 184.79 g: 146.87 g: 48.54 mL, placed in a 500 mL flask, 0.06 g of sodium hydroxide was added as a catalyst, and Titanium isopropoxide. (Sigma-Aldrich Co., Ltd.) 21.32g was added, but when stirred for 10 hours at 60 ℃ Gel is difficult to control the reaction time was shortened to 5 hours. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 30000, polydispersity index 5.2). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Example  2-10

KBM-303 (Shinetsu), TEOS (Sigma-Aldrich) and H ₂ O were mixed at a ratio of 258.70 g: 90.62 g: 44.57 mL, and placed in a 500 mL flask, 0.06 g of sodium hydroxide was added as a catalyst, and Titanium isopropoxide. (Sigma-Aldrich, Inc.) was added 4.26g and stirred at 60 ° C for 10 hours. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 18000, polydispersity index 3.9). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Comparative example  2-1

KBM-403 (Shinetsu), TEOS (Sigma-Aldrich) and H ₂ O (Sigma-Aldrich) were mixed in a ratio of 350.96g: 2.50g: 40.66mL and placed in a 500mL flask, and 0.06g sodium hydroxide was catalyzed. And Titanium isopropoxide (Sigma-Aldrich) were added 0.85g and stirred at 60 ° C for 10 hours. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 4000, polydispersity index 1.8). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to the siloxane resin obtained above, to 100 parts by weight of the siloxane resin, thereby obtaining a hard coating resin composition.

Comparative example  2-2

KBM-303 (Shinetsu), TEOS (Sigma-Aldrich) and H ₂ O were mixed at a ratio of 295.66 g: 60.94 g: 43.22 mL, placed in a 500 mL flask, and 0.06 g of sodium hydroxide was added as a catalyst at 60 ° C. Stir for 10 hours. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 21000, polydispersity index 2.3). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Comparative example  2-3

KBM-303 (Shinetsu Co., Ltd.) and Titanium isopropoxide (Sigma-Aldrich Co., Ltd.), H ₂ O, were mixed in a ratio of 365.87 g: 4.26 g: 40.66 mL, placed in a 500 mL flask, and 0.06 g of sodium hydroxide was added as a catalyst. Stir at 10 ° C. for 10 hours. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 5000, polydispersity index 2.6). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

Comparative example  2-4

KBM-303 (Shinetsu Co., Ltd.), TEOS (Sigma-Aldrich Co., Ltd.) and H ₂ O were mixed at a ratio of 36.96 g: 281.25 g: 52.68 mL, and placed in a 500 mL flask, followed by reaction by adding 0.06 g of sodium hydroxide as a catalyst. When stirred for 10 hours at 60 ℃ Gel was difficult to control the reaction time was shortened to 5 hours to react. Thereafter, the mixture was filtered using a 0.45 um Teflon filter to obtain a siloxane resin (weight average molecular weight 48000, polydispersity index 6.8). Next, 3 parts by weight of IRGACURE 250 (BASF, Inc.) as a photoinitiator was added to 100 parts by weight of the siloxane resin to obtain a resin composition for hard coating.

< 2nd Measurement example >

On one surface of a 75 μm-thick polyethylene terephthalate film (manufacturer: Kolon, product name: HP34P) based on the resin compositions for hard coating of Examples 2-1 to 2-10 and Comparative Examples 2-1 to 2-4 10, 20, 30u㎛ coated after varying the thickness, and dried for 30 minutes in an oven at 80 ℃, irradiated with 1,000mJ / ㎠ at a roughness of 80mW / ㎠ in the direction of applying the hard coating composition with an ultraviolet irradiation device Heat treatment for 24 hours in an 85 ℃ oven to prepare a hard coating film. Subsequently, the physical properties of the prepared hard coat film were evaluated according to the following method, and the results are shown in Table 2 below.

(1) Surface hardness: Pencil hardness was measured at 750 gf load at a speed of 180 mm / min in accordance with ASTM D3363 using a pencil hardness tester manufactured by IMOTO, Japan.

(2) Curling: The coated film was cut into 100 mm × 100 mm and left for 24 hours at 25 ° C. and 50% RH, and then measured as the maximum value of the distance from one side of each corner to the plane when placed on the plane. .

(3) Abrasion resistance: After fixing the film cut to 20cm X 5cm on the plane with the adhesive tape (3M) with the coated side up, the surface was reciprocated for 1000 times at a load of 1kgf and 15RPM with a rod wrapped with # 0000 nonwoven fabric. When the scratch is generated or not when the scratch occurs, it is judged to be good if it does not occur, and reflected in Table 2 below.

TABLE 2

As can be seen through Table 2, compared with Comparative Example 2-1 using an alkoxy silane having a general epoxy group rather than an alicyclic epoxy group, Examples 2-3 to 2-10 all showed excellent surface hardness and wear resistance. In particular, although Comparative Example 2-1 basically did not include an alkoxy silane having an alicyclic epoxy group even though the alkoxy metal was added, the surface hardness as well as the curl characteristics were not significantly improved. In Comparative Example 2-2, the TEOS addition amount was increased to improve the surface hardness than Comparative Example 2-1, but it was also confirmed that curling properties were not improved because no alkoxy metal was added. On the contrary, in Examples 2-1 to 2-2, the amount of TEOS added was less than that of Comparative Example 2-2, and thus the hardness was slightly lower, but it was confirmed that the addition of the alkoxy metal greatly improved the curl.

In addition, in case of Comparative Example 2-3, the surface hardness and abrasion resistance were relatively low due to not applying TEOS. In Comparative Example 2-4, the surface hardness and the abrasion resistance were sufficiently secured, but the ratio of TEOS was It was too high, and the alkoxy metal compound was not added, and the effect of improving curl properties was not large. On the contrary, in Examples 2-1 to 2-10, it was confirmed that the surface hardness, abrasion resistance, and curl characteristics were all balanced in comparison with Comparative Examples 2-3 and 2-4.

Therefore, since the hard coating film prepared using the hard coating resin composition of the present invention is excellent in hardness, wear resistance and curl characteristics, it could be confirmed through experiments that it may be particularly suitable as a film for display protection.

However, Examples 2-5 and 2-6 in which the content of TEOS is 75 mol% or more based on the total alkoxy silane and 0.2 to 5.0 mol% of the alkoxy silane (Titanium isopropoxide) is based on the total alkoxy silane. Compared with Examples 2-1 to 2-4 and 2-7 to 2-10, the hardness and abrasion resistance were not changed, but curling properties were slightly behind. Accordingly, the content of TEOS is 17 mol% to 20 mol% based on the total alkoxy silane, and the alkoxy metal is included in the range of 0.2 mol% to 3 mol% based on the total alkoxy silane. Examples 2-3, 2-7 And 2-8, but Examples 2-4, wherein the content of TEOS is 29 mol% to 52 mol% based on the total alkoxy silane and the alkoxy metal is included in the range of 1 mol% to 5.0 mol% based on the total alkoxy silane. 2-9 and 2-10 were analyzed to be more preferred.

[ 3rd Example ]

Polymerization example  One

KBM-303 (Shinetsu), Titanium isopropoxide (Sigma-Aldrich) and H ₂ O were mixed in a 500mL flask at a ratio of 245.2g: 1.4g: 27.2mL and then sodium hydroxide (Sigma-Aldrich) 0.1g Was added as a catalyst and the reaction proceeded while removing the alcohol produced by the Dean Stark apparatus while stirring at 60 ° C. for 10 hours to obtain a siloxane resin polymer 1.

Polymerization example  2

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

Polymerization example  3

KBM-303 (Shinetsu), Titanium isopropoxide (Sigma-Aldrich) and H ₂ O were mixed in a 500 mL flask at a ratio of 234.1 g: 14.2 g: 27.2 mL, and then 0.1 g sodium hydroxide (Sigma-Aldrich) Was added as a catalyst and the reaction proceeded while removing the alcohol produced by the Dean Stark apparatus while stirring at 60 ° C. for 10 hours to obtain a siloxane resin polymer 3.

Polymerization example  4

KBM-303 (Shinetsu), Aluminum ethoxide (Sigma-Aldrich) and H ₂ O were mixed in a ratio of 259.8 mL: 1.62 g: 27.2 mL into a 500 mL flask, and 0.1 g sodium hydroxide was added as a catalyst. The reaction was carried out while removing the alcohol produced by the Dean Stark apparatus while stirring at 10C to obtain a siloxane resin polymer 4.

compare Polymerization example  One

KBM-303 (Shinetsu Co., Ltd.), H ₂ O was mixed in a 500 mL flask at a ratio of 246.4 g: 27.2 mL, and then 0.1 g of sodium hydroxide (Sigma-Aldrich) was added as a catalyst and stirred at 60 ° C. for 10 hours. The reaction was carried out while removing the alcohol produced by the Dean Stark apparatus while obtaining the siloxane resin polymer 5.

compare Polymerization example  2

KBM-303 (Shinetsu), Titanium isopropoxide (Sigma-Aldrich) and H ₂ O were mixed in a 500 mL flask at a ratio of 231.6 g: 17.1 g: 27.2 mL, and then sodium hydroxide (Sigma-Aldrich) 0.1 g Was added as a catalyst and the reaction proceeded while removing the alcohol produced by the Dean Stark apparatus while stirring at 60 ° C. for 10 hours to obtain a siloxane resin polymer 3.

The contents of the polymerization examples 1 to 4 and comparative polymerization examples 1 to 2 are summarized as follows.

TABLE 3

Example  3-1

Ethyl oxetanyl methyl ether (manufacturer: Toagosei Co., Ltd., OXT221) and cyclo aliphatic epoxide (manufactured by Daicel Co., Ltd., product name: Celloxide2021P) were prepared by mixing in a weight ratio of 1: 1. It mixed with the produced siloxane resin in the weight ratio of 3: 1 (siloxane resin = 3). 40% by weight of methyl ethyl ketone as a diluting solvent, 1% by weight of triarylsulfonium hexafluoroantimonate (Sigma-Aldrich) as a photoinitiator, and a silicone-based leveling agent as an additive based on the total weight of the mixed mixture : BYK, product name: BYK-333) 0.4 wt% was added, and stirred for 1 hour using a stirrer to prepare a hard coat resin composition.

Example  3-2

Ethyl oxetanyl methyl ether (manufacturer: Toagosei Co., Ltd., product name: OXT221) and cyclo aliphatic epoxide (manufactured by Daicel Co., Ltd., product name: Celloxide2021P) were prepared by mixing in a weight ratio of 1: 1. The siloxane resin thus prepared was mixed at a weight ratio of 9: 1 (siloxane resin = 9). After the hard coating resin composition was prepared in the same manner as in Example 3-1.

Example  3-3

Ethyl oxetanyl methyl ether (manufacturer: Toagosei Co., Ltd., product name: OXT221) and cyclo aliphatic epoxide (manufactured by Daicel Co., Ltd., product name: Celloxide2021P) were prepared by mixing in a weight ratio of 1: 1. It mixed with the produced siloxane resin in the weight ratio of 3: 1 (siloxane resin = 3). After the hard coating resin composition was prepared in the same manner as in Example 3-1.

Example  3-4

Ethyl oxetanyl methyl ether (manufacturer: Toagosei Co., Ltd., product name: OXT221) and cyclo aliphatic epoxide (manufactured by Daicel Co., Ltd., product name: Celloxide2021P) were prepared by mixing in a weight ratio of 1: 1. It mixed with the produced siloxane resin in the weight ratio (siloxane resin = 3) of 3: 2. After the hard coating resin composition was prepared in the same manner as in Example 3-1.

Example  3-5

Phenyl epoxy acrylate (manufacturer: Miwon Corporation, product name: PE110) and bisphenol A type EO addition diacrylate (manufacturer: Miwon Corporation, product name: M2100) was prepared by mixing in a weight ratio of 1: 1, in the polymerization example 2 The prepared siloxane resin was mixed at a weight ratio of 3: 1 (siloxane resin = 3). 40 wt% methyl ethyl ketone as diluent solvent, 0.67 wt% triarylsulfonium hexafluoroantimonate (Sigma-Aldrich) as photoinitiator, 1-hydroxycyclohexyl phenyl based on the total weight of the mixed mixture 0.33% by weight of ketone (manufacturer: Basf, trade name: Irgacure 184), 0.4% by weight of silicone-based leveling agent (manufacturer: BYK, product name: BYK-333) was added as an additive, and stirred for 1 hour using a stirrer to hard-coat resin The composition was prepared.

Example  3-6

Ethyl oxetanyl methyl ether (manufacturer: Toagosei Co., Ltd., product name: OXT221) and cyclo aliphatic epoxide (manufactured by Daicel Co., Ltd., product name: Celloxide2021P) were prepared by mixing in a weight ratio of 1: 1. It mixed with the produced siloxane resin in the weight ratio of 3: 1 (siloxane resin = 3). After the hard coating resin composition was prepared in the same manner as in Example 3-1.

Example  3-7

Ethyl oxetanyl methyl ether (manufacturer: Toagosei Co., Ltd., OXT221) and cyclo aliphatic epoxide (manufactured by Daicel Co., Ltd., product name: Celloxide2021P) were prepared by mixing in a weight ratio of 1: 1. It mixed with the produced siloxane resin in the weight ratio of 3: 1 (siloxane resin = 3). After the hard coating resin composition was prepared in the same manner as in Example 3-1.

Comparative example  3-1

40 wt% of methyl ethyl ketone as a diluting solvent based on the weight of the siloxane resin prepared in the polymerization example 2, 1 wt% of triarylsulfonium hexafluoroantimonate (Sigma-Aldrich) as an photoinitiator, additive A silicon-based leveling agent (manufacturer: BYK, product name: BYK-333) was added to 0.4 wt%, and stirred for 1 hour using a stirrer to prepare a hard coat resin composition.

Comparative example  3-2

Ethyl oxetanyl methyl ether (manufacturer: Toagosei Co., Ltd., product name: OXT221) and cyclo aliphatic epoxide (manufactured by Daicel Co., Ltd., product name: Celloxide2021P) were prepared by mixing in a weight ratio of 1: 1. It was mixed with the prepared siloxane resin in a weight ratio of 1: 1. After the hard coating resin composition was prepared in the same manner as in Example 3-1.

Comparative example  3-3

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

Comparative example  3-4

Ethyl oxetanyl methyl ether (manufacturer: Toagosei Co., Ltd., OXT221) and cyclo aliphatic epoxide (manufactured by Daicel Co., Ltd., product name: Celloxide2021P) were prepared by mixing in a weight ratio of 1: 1, and Comparative Polymerization Example 1 It was mixed with the siloxane resin prepared in the weight ratio of 3: 1. After the hard coating resin composition was prepared in the same manner as in Example 3-1.

< 3rd Measurement example >

On one side of a 75 μm-thick polyethylene terephthalate film (manufacturer: Kolon, product name: HP34P) based on the resin compositions of Examples 3-1 to 3-7 and Comparative Examples 3-1 to 3-4 prepared as described above. After application, it was dried in an oven at 80 ° C. 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 irradiation device, and then heat-treated in an oven at 85 ° C. for 24 hours. To prepare a hard coating film having two thicknesses of 85㎛ and 100㎛ respectively. Subsequently, the following physical property evaluation was performed with the manufactured hard coat film.

(1) Surface hardness: Pencil hardness was measured at 750 gf load at a speed of 180 mm / min in accordance with ASTM D3363 using a pencil hardness tester manufactured by IMOTO, Japan.

(2) Flexibility: With the coating layer facing outwards, it was wound around a rod having a radius interval in units of 1 mm to check the minimum radius where cracks did not occur in the coating surface.

(3) Curling: When the coated film was cut into 100 mm × 100 mm and placed on a flat surface, one side of each corner was measured as the maximum value of the distance from the flat surface.

TABLE 4

From the results of Table 4, it can be seen that the hard coating films of Examples 3-1 to 3-7 exhibited excellent results in terms of pencil hardness, flexibility, and curl characteristics, and cracks did not occur even when wound on rods having a radius of 6 mm or less. It was confirmed that the flexibility is very excellent.

On the contrary, when the coating layer was formed using only the siloxane resin prepared through the polymerization example, the flexibility was remarkably inferior as in Comparative Example 3-1, and in Comparative Example 3-2 in which the ratio of the siloxane resin was decreased, the surface hardness was not secured. When using the siloxane resin prepared in Comparative Polymerization Example 1, it was confirmed that the metal content included in the siloxane is insignificant as in Comparative Examples 3-3 and 3-4, so that curl generation does not improve when the hard coating layer is formed. Could.

Therefore, it was confirmed through experiments that the hard coat film manufactured using the hard coat resin composition of the present invention is excellent in strength, flexibility, and curl characteristics, and thus can be applied as a display protective film.

Claims (29)

1. Resin composition for hard coating comprising a siloxane resin chemically bonded by alkoxy silane represented by the formula (1) and alkoxy metal compound represented by the formula (2):

   <Formula 1> R ¹ _n Si (OR ² ) _4-n

   <Formula 2> M (OR ³ ) m

   In Formulas 1 to 2, R ¹ is a linear C ₁ to C ₃ alkyl group including an alicyclic epoxy group, R ² is a linear or branched C ₁ to C ₄ alkyl group, R ³ is a linear or branched An alkyl group of C ₁ to C ₄ . In addition, M is at least one metal element selected from the group consisting of aluminum, titanium and zinc, n is an integer of 1 to 3, m is an integer of 2 to 4.
2. The alkoxy silane represented by the formula (1) is 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane and 2 -(3,4-epoxycyclohexyl) ethyltripropoxysilane is at least one selected from a resin composition for hard coating.
3. The resin composition for hard coating of claim 1, wherein the alkoxy metal compound is included in an amount of 0.2 mol% to 5.0 mol% based on the total moles of the alkoxy silane and the alkoxy metal compound.
4. The resin composition of claim 3, wherein the siloxane resin has a weight average molecular weight of 5,000 to 22,000, and a polydispersity index (PDI) of 1.5 to 3.1.
5. The resin composition for hard coating according to claim 3, wherein the resin composition for hard coating comprises the siloxane resin as a first component, and further comprises at least one of an epoxy resin and an acrylic resin as a second component.
6. The resin composition for hard coating according to claim 5, wherein the first component and the second component are mixed in a weight ratio of 9: 1 to 6: 4.
7. The monomer of claim 5, wherein the second component comprises at least one functional group selected from 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. It is an oligomer, The resin composition for hard coatings characterized by the above-mentioned.
8. The resin composition for hard coating according to claim 1, wherein the siloxane resin further comprises an alkoxy silane represented by the following formula (3) to form a chemical bond.

   <Formula 3> Si (OR ³ ) ₄

   In Formula 3, R ³ is a C ₁ to C ₄ linear or branched alkyl group.
9. The alkoxy silane represented by Formula 1 is 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane and -(3,4-epoxycyclohexyl) ethyltripropoxysilane is at least one selected from a resin composition for hard coating.
10. The alkoxy silane represented by Formula 1 and the alkoxy silane represented by Formula 3 have a molar ratio of 99: 1 to 20:80,

    At this time, the alkoxy metal compound represented by the formula (2) is a hard coating, characterized in that containing 0.2 mol% to 5.0 mol% based on a total of 100 mol of the alkoxy silane represented by the formula (1) and the alkoxy silane represented by the formula (3) Resin composition.
11. The resin composition for hard coating of claim 10, wherein the alkoxy silane represented by Chemical Formula 1 and the alkoxy silane represented by Chemical Formula 3 have a molar ratio of 85:15 to 45:55.
12. The resin composition for hard coating according to claim 8, wherein the siloxane resin has a weight average molecular weight of 3,000 to 50,000 and a polydispersity index (PDI) of 1.5 to 7.0.
13. The resin composition for hard coating according to claim 8, wherein the resin composition for hard coating comprises the siloxane resin as a first component, and further comprises at least one of an epoxy resin and an acrylic resin as a second component.
14. The resin composition for hard coating according to claim 13, wherein the first component and the second component are mixed in a weight ratio of 9: 1 to 6: 4.
15. The monomer of claim 13, wherein the second component comprises at least one functional group selected from 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. It is an oligomer, The resin composition for hard coatings characterized by the above-mentioned.
16. The resin composition for hard coating according to any one of claims 1 to 15, further comprising at least one additive selected from the group consisting of an organic solvent, a photoinitiator, a thermal initiator, an antioxidant, a leveling agent and a coating aid. Hard coating resin composition, characterized in that.
17. Hard coating film comprising a base film and a hard coating layer formed by curing the resin composition for hard coating of any one of claims 1 to 4 on at least one surface of the base film.
18. 18. The hard coat film of claim 17, wherein the hard coat film has a surface hardness in the direction in which the coating layer is formed, based on ASTM D3363, 4H to 9H.
19. A hard coating film comprising a base film and a hard coating layer formed on at least one surface of the base film by curing the resin composition for hard coating according to any one of claims 5 to 7.
20. 20. The hard coating film of claim 19, wherein the hard coating film has a surface hardness in the direction in which the coating layer is formed, based on ASTM D3363 measurement standards, 4H to 9H.
21. The hard coating film of claim 19, wherein the hard coating film has a minimum radius of curvature of 2 to 6 mm in which a crack is not generated in the coating layer when bending is formed in an opposite direction in which the coating layer is formed.
22. Hard coating film comprising a base film and a hard coating layer formed by curing the resin composition for hard coating of any one of claims 8 to 12 on at least one surface of the base film.
23. The hard coating film of claim 22, wherein the hard coating film has a surface hardness in the direction in which the coating layer is formed, based on ASTM D3363 measurement standards, 4H to 9H.
24. 23. The method of claim 22, wherein the hard coating film is cut into 100mm X 100mm and left for 24 hours at 25 ℃ and 50% RH (relative humidity) conditions, when placed in the plane of the distance that one side of each corner is separated from the plane Hard coating film, characterized in that the maximum value is 30mm or less.
25. Hard coating film comprising a base film and a hard coating layer formed by curing the resin composition for hard coating of any one of claims 13 to 15 on at least one surface of the base film.
26. 26. The hard coating film of claim 25, wherein the hard coating film has a surface hardness in the direction in which the coating layer is formed, based on ASTM D3363 measurement standards, 4H to 9H.
27. 26. The method of claim 25, wherein the hard coating film is cut into 100mm X 100mm and left for 24 hours at 25 ℃ and 50% RH (relative humidity) conditions, when placed in the plane of the distance that one side of each corner is separated from the plane Hard coating film, characterized in that the maximum value is 30mm or less.
28. 26. The hard coating film of claim 25, wherein the hard coating film has a minimum radius of curvature of 2 to 6 mm in which a crack is not generated in the coating layer when bending is formed in an opposite direction in which the coating layer is formed.
29. Hard coating film comprising a base film and a hard coating layer formed by curing the resin composition for hard coating of claim 16 on at least one surface of the base film.

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