TWI611932B - Printable functional hard coating film and preparation method thereof - Google Patents

Abstract

The invention discloses a printable functional hard coating film and a preparation method thereof. The hard coating film includes a structure in which a substrate layer, a release layer, and a hard coating layer are sequentially stacked. The release layer includes a vinyl or The hard coat layer of a silicone resin obtained by the addition reaction of a hexene-based polydimethylsiloxane and a hydrosiloxane contains a polymer resin having a glass transition temperature of 30 ° C or higher. The hard coating film has excellent hardness and print adhesion, and the release layer and the hard coating layer are easily peeled off. Therefore, after the printing or vapor deposition on the surface of the hard coating layer, the release layer and the hard coating layer can be peeled clean.

Description

Printable functional hard coating film and preparation method thereof

The invention relates to a printable functional hard coating film and a preparation method thereof. More specifically, the present invention relates to a hard coating film and a method for preparing the same. The hard coating film can realize printing and vapor deposition treatment on the hard coating layer, and is easily peeled from the release film.

Recently, in order to reduce the thickness step due to printing, a substrate-less transfer type hard coating film has been widely used. Most substrate-less transfer-type hard coat films are formed by applying and curing a hard coat resin composition on a release film (see Korean Laid-Open Patent Publication No. 2015-77428). After that, a printing layer using ink or a pattern is formed on the hard coating layer, and a plastic injection product is attached to the printing layer, and then the transfer is performed by removing the release film.

The release film included in the hard coating film is composed of a base material layer and a release layer, and a silicone resin or a fluorine-based resin is mainly used as a raw resin for the release layer bonded to the hard coating layer.

Among them, the silicon-based release layer has the advantages of low peeling force and low price. However, in the process of forming a hard coating layer directly on the release layer in order to prepare a substrate-free transfer type product, The gradient of the surface layer of the mold layer is difficult to form a normal coating, so many problems such as poor coating such as non-coating and pin-holes may occur. In addition, as for the silicon-based release layer, the surface tension is low, so the hard coating layer and the release layer may be peeled off during the manufacturing process to break the hard coating layer, or it may be wound in layers after preparation. The problem is that the hard coat is transferred to other layers that it contacts during the storage process.

Due to this problem, a melamine-based or acrylic-based release layer having a high surface tension is being used instead of a silicon-based release layer on a substrate-less transfer-type hard coating film.

However, in the case of a melamine-based or acrylic release layer, unlike a silicon-based release layer, although the surface layer has good overcoating, the peeling force is high and it is difficult to control the peeling force, so that it is peeled off after the printing process. When the film is molded, it cannot be peeled off cleanly, so there is a problem that a hard coating residue is left on the release surface.

Technical problem to be solved

Therefore, an object of the present invention is to provide a hard coating film having excellent peelability of a release film, an appearance of a hard coating layer, and storage stability, and a method for preparing the same.

Technical solutions

According to the above object, the present invention provides a hard coating film including a structure in which a base layer or backing layer, a release layer, and a hard coating layer are sequentially laminated. The type layer includes a silicone resin obtained by subjecting a polydimethylsiloxane having a vinyl group or a hexenyl group to an addition reaction with a hydrogensiloxane. ), The hard coat layer contains a polymer resin having a glass transition temperature (Tg) of 30 ° C or higher.

In addition, according to another object, the present invention provides a method for preparing a hard coating film, which includes the following steps: (1) adding a polydimethylsiloxane having a vinyl group or a hexenyl group and a hydrosiloxane Reaction to prepare a silicone resin; (2) coating a composition containing a silicone resin on a substrate layer to form a release layer; and (3) coating on the release layer including a glass transition temperature of 30 ° C or higher A hard coating resin composition of a polymer resin, thereby forming a hard coating.

In the hard coating film of the present invention, the hard coating layer has excellent hardness and printability, and is easily peeled from the release layer. Therefore, after the surface of the hard coating layer is printed or vapor-deposited, the release film and the The hard coating is peeled clean.

In particular, the hard coating film uses a hard coating resin having a relatively high glass transition temperature. Therefore, even when an external force is applied during roll winding and post-process, the hard coating does not break or Transfer to other layers, so it can be stored for a long time.

In addition, as for the hard coating film, the adhesion to the release layer is adjusted, so the release layer and the hard coating layer will not easily peel off during roll winding and subsequent processes, and it is used for the hard coating layer. The surface tension of the prepared composition is adjusted, so that a good coating can also be achieved on the silicon-based release layer.

Therefore, the hard coating film of the present invention can be used as an anti-scattering film (anti-scattering film) after being subjected to processes such as ink printing and metal vapor deposition on the surface of the hard coating layer, and then adhered to the glass plate with a transparent tape or the like. scattering film), or after injection of plastic products, it can be used as the exterior material of mobile phones or tablets.

The present invention will be described in more detail below with reference to the drawings. In order to facilitate understanding, dimensions, intervals, and the like on the drawings may be enlarged and shown, and content that is obvious to those having ordinary knowledge in the field to which the present invention pertains may be omitted from illustration.

Referring to FIG. 1, a hard coating film according to an example includes a structure in which a first base material layer 111, a first release layer 121, and a hard coating layer 130 are laminated in this order.

Referring to FIG. 2, a hard coating film according to another different example includes a structure in which a first release layer 121, a first substrate layer 111, a first release layer 121, and a hard coat layer 130 are laminated in this order.

Referring to FIG. 3, a hard coating film according to yet another example includes a sequential layer including a first substrate layer 111, a first release layer 121, a hard coating layer 130, a second release layer 122, and a second substrate layer 112. Product structure.

The hard coating film may further include a printed layer, an evaporation layer, or an adhesive layer on the hard coating layer.

Referring to FIG. 4, a hard coating film according to another different example includes a first substrate layer 111, a first release layer 121, a hard coating layer 130, an adhesive layer 140, a second release layer 122, and a second substrate layer. 112 is a sequential layered structure.

Each structure layer will be specifically described below.

The first base material layer 111 and the second base material layer 112 may be transparent films, and may be, for example, transparent polymer films. The substrate layer may include a polymer resin selected from the group consisting of polyolefin, polystyrene, polycarbonate, polyester, cellulose, acrylic, polyvinyl chloride, and mixtures thereof. Specifically, the substrate layer may include a material selected from the group consisting of polyethylene, polypropylene, polystyrene, polycarbonate, polyethylene naphthalate, polyethylene terephthalate, and polybutylene terephthalate. Polymer esters of alcohol esters, cellulose triacetate, acrylic acid, polyvinyl chloride and mixtures thereof.

In addition, in order to improve mechanical strength or optical function, the base material layer may be a base material layer obtained by uniaxially stretching or biaxially stretching the film, if necessary.

The thickness of the substrate layer can be selected according to the material, but its thickness can be 20 to 550 μm, and preferably 50 to 188 μm.

The first release layer 121 and the second release layer 122 include a silicone resin having a low peeling force. In the case of the conventional melamine-based or acrylic release film, when the hard-coat layer is peeled off, there is a problem that the hard-coat layer remains on the release film, but this problem can be solved according to the present invention.

The silicone resin contained in the release layer may be obtained by subjecting polydimethylsiloxane and hydrosiloxane to an addition reaction. Specifically, the silicone resin may be formed by reacting a vinyl group or a hexenyl group of polydimethylsiloxane with a Si-H group of hydrosiloxane. Thereby, the silicone resin can have both a repeating unit of polydimethylsiloxane and a repeating unit of hydrosiloxane.

The silicone resin may be obtained by an addition reaction of 10 parts by weight of polydimethylsiloxane and 0.05 to 1.0 part by weight of hydrosiloxane. When the reaction amount of hydrosiloxane is 0.05 parts by weight or more, it is beneficial to suppress the reduction of the residual adhesion rate and the occurrence of small molecule migration problems. When the reaction amount of hydrosiloxane is 1.0 part by weight or less, The release holding force can be more excellent.

As a specific example, polydimethylsiloxane can be represented by the following Chemical Formula 1.

[Chemical Formula 1]

In the above Chemical Formula 1, X is a vinyl or hexenyl group, Me is a methyl group, n is an integer of 5 to 100, preferably an integer of 5 to 50, and m + n is an integer of 1,500 to 15,000, preferably 3,000 An integer of ~ 10,000.

The molecular weight of polydimethylsiloxane can be about 150,000 to 600,000 g / mol.

The hydrosiloxane can be represented by the following chemical formula 2.

[Chemical Formula 2]

In the above Chemical Formula 2, Me is a methyl group, a + b is an integer from 2 to 100, and b ≦ a.

Commercial products of hydrosilane can be exemplified by Shin-Etsu's X-92-122 and Dow Corning's SYL-oFF 7048, SYL-OFF 7599, SYL-OFF 7678, SYL-OFF 7689, etc. Not limited to this.

Thereby, the silicone resin can have both the repeating unit of the above Chemical Formula 1 (a unit enclosed by square brackets) and the repeating unit of the above Chemical Formula 2 (a unit enclosed by square brackets).

The thickness (dry thickness) of the release layer can be 0.05 to 1 μm. When the thickness of the release layer is 0.05 μm or more, it is beneficial to have a low release force and excellent release deviation from the hard coating layer. When the thickness of the release layer is 1 μm or less, it is more beneficial to ensure anti-blocking. (Anti-blocking) characteristics.

The surface tension of the release layer may be 20 to 30 dyne / cm ² .

The release force (peeling force) of the release layer to the standard tape can be 3 to 20 gf / in, and more preferably 4 to 15 gf / in. When the release force is in a better range, the residue of the hard coating layer will not remain on the release layer when the release film is peeled off, and during the roll winding and subsequent processes, the release layer can be suppressed from being hardened. Risk of coating peeling.

The hard coat layer 130 is formed on a release layer of a release film, and has a role of ensuring adhesion to a printed or vapor-deposited layer in subsequent processing.

The hard coat layer may include a thermoplastic resin, a thermosetting resin, an ionizing radiation curable resin, and the like. Preferably, in order to improve the surface hardness and exhibit high hard coatability, an ionizing radiation (ultraviolet or electron beam) curable resin may be included.

Specific examples of the thermoplastic resin and the thermosetting resin include polyester resin, acrylic resin, acrylic urethane resin, polyester acrylate resin, urethane acrylate resin, epoxy acrylate resin, and amino group. Ethyl formate resin, epoxy resin, polycarbonate resin, cellulose resin, acetal resin, polyethylene resin, polystyrene resin, polyamide resin, polyimide resin , Melamine resin, phenol resin, silicon resin and mixtures thereof.

As the ionizing radiation-curable resin, a photopolymerizable prepolymer that is crosslinked and cured by irradiation with ionizing radiation can be used. The photopolymerizable prepolymer can be a cationically polymerizable and radically polymerizable photopolymerizable prepolymer. . Examples of the cationic polymerizable photopolymerizable prepolymer include epoxy resins and vinyl ester resins, and epoxy resins include bisphenol epoxy resins, novolac epoxy resins, and resins. Alicyclic epoxy resins, aliphatic epoxy resins, and mixtures thereof. From the viewpoint of hard coatability, the radical polymerization type photopolymerizable prepolymer can be preferably used to have a three-dimensional network structure by having two or more acrylyl groups in one molecule and curing by crosslinking. Acrylic prepolymer (hard prepolymer).

Examples of the acrylic prepolymer include urethane acrylate, polyester acrylate, epoxy acrylate, melamine acrylate, polyfluoroalkyl acrylate, silicon acrylate, and mixtures thereof. The urethane acrylate prepolymer can be obtained, for example, by esterification of a polyurethane oligomer with (meth) acrylic acid. The polyurethane oligomer is a polyether polyol ( It is obtained by reacting a polyether polyol or a polyester polyol with a polyisocyanate. For polyester acrylate prepolymers, for example, polyesters having hydroxyl groups at both ends can be obtained by condensation of polyvalent carboxylic acids and polyvalent alcohols. The hydroxyl group of the polymer is obtained by esterification with (meth) acrylic acid, or the hydroxyl group at the terminal of the oligomer obtained by addition of a polycarboxylic acid and an alkylene oxide is esterified with (meth) acrylic acid. And get. As for the epoxy acrylate-based prepolymer, for example, an oxirane ring and a (meth) acrylic acid can be esterified by a bisphenol epoxy resin or novolac epoxy resin having a relatively low molecular weight. To get.

The hard coat layer may further include a photopolymerizable monomer in order to impart various properties such as improvement in cross-linking curability or adjustment of curing shrinkage. Examples of the photopolymerizable monomer include a monofunctional (meth) acrylic monomer (example: 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl ( (Meth) acrylate, butoxyethyl (meth) acrylate, etc.), difunctional (meth) acrylic monomer (example: 1,6-hexanediol di (meth) acrylate, neopentyl Alcohol (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate glycol di (meth) acrylate, etc.), trifunctional or more (meth) acrylic monomers (eg, dipentaerythritol hexa (meth) acrylate, trimethylpropane tri (meth) acrylate, pentaerythritol tri (methyl) Based) acrylate (pentaerythritol tri (meth) acrylate, etc.). These photopolymerizable monomers can be used alone or in combination of two or more.

When the hard coat layer is formed by curing by ultraviolet irradiation, the hard coat layer may further include a photopolymerization initiator in addition to the photopolymerizable prepolymer and the photopolymerizable monomer. As the photopolymerization initiator, common initiators widely used for curing of ultraviolet curable resins can be used. For example, oxime esters, acetophenones, benzophenones, benzoins, and oxygen can be used. Photoinitiators such as xanthones, triazines, halomethyloxadiazoles, and lophine dimers. These initiators can be used alone or in combination of two or more.

The hard coat layer may be formed by applying a hard coat resin composition and curing it on a release layer of a release film as required.

At this time, as the solvent of the hard coat resin composition, a solvent having a low surface tension is preferably used so that a deviation in surface tension from the coated release layer can be minimized. Thereby, the hard-coat resin composition can have a surface tension that is lower than the surface tension of the release layer or a difference from the surface tension of the release layer within 10 dyne / cm ² .

The hard coating layer includes a polymer resin having a glass transition temperature (Tg) of 30 ° C or higher, such as 30 to 60 ° C, 30 to 70 ° C, 30 to 80 ° C, or 30 to 90 ° C. Generally, a lower Tg is a soft polymer, and a higher Tg is a hard polymer. When the Tg is less than 30 ° C, the raw materials are soft and the surface hardness is too low, so that the coating is easily broken or transferred to the outside due to the winding pressure or external force during winding and processing. Therefore, the use of Tg is above 30 ° C. Raw materials to ensure a minimum hardness that will not cause the coating to break or transfer due to winding pressure or external forces.

The thickness of the hard coating layer may be 0.1 to 30 μm, and preferably 1 to 10 μm. When the thickness of the hard coat layer is within a preferable range, the hard coat layer can exhibit sufficient surface hardness, and can be more excellent in haze, transmittance, and adhesion of the coating film.

In addition, the hard coating layer may have a thickness of 0.1 to 30 μm and a surface hardness of 1H or more.

The adhesion of the hard coating to the release layer can be 4 ~ 10 gf / in. When the interlayer adhesion is in a better range, the peeling between the release layer and the hard coating layer can be more suppressed during the process or processing, and the hard coating and the release layer can be peeled clean, so it can be more beneficial to suppress Generation of residues.

The adhesive layer 140 is formed on one side of the hard coat layer 130, and thereafter, it has an effect of improving the adhesion to a glass plate or the like.

The adhesive layer can be formed using a conventional adhesive resin composition.

The adhesive composition can be formed by polymerizing more than one acrylic monomer and a carboxyl group-containing unsaturated monomer, respectively. Specific examples of the acrylic monomer include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, isopropyl Butyl (meth) acrylate, tert-butyl (meth) acrylate, cyclohexyl (meth) acrylate, ethylhexyl (meth) acrylate, tetrahydrofuran methyl (meth) acrylate (Tetrahydrofurfuryl ( meth) acrylate), hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxy-3-chloropropyl (meth) acrylate, 4-hydroxybutyl (methyl Group) acrylate, glycerol (meth) acrylate, methyl α-hydroxymethacrylate, ethyl α-hydroxymethacrylate, propyl α-hydroxymethacrylate, butyl α-hydroxy Methacrylate, 2-methoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxytrimethacrylate Glycol (meth) acrylate, methoxytripropylene glycol (meth) acrylate, poly ( Ethylene glycol) methyl ether (meth) acrylate, tetrafluoropropyl (meth) acrylate, 1,1,1,3,3,3-hexafluoroisopropyl (meth) acrylate, eight Octafluoropentyl (meth) acrylate, heptadecafluorodecyl (meth) acrylate, isobornyl (meth) acrylate acrylate), dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate ) Dicyclopentanyloxyethyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, and mixtures thereof, preferably methyl (meth) acrylate, butyl (Meth) acrylates and mixtures thereof. Specific examples of the carboxyl group-containing unsaturated monomer include acrylic acid, methacrylic acid, 2- (meth) acrylic acid oxyacetic acid, 3- (meth) acrylic acid oxypropionic acid, and 4- (methyl ) Acrylic acid oxybutyric acid, itaconic acid, maleic acid, maleic anhydride and mixtures thereof, preferably methacrylic acid, acrylic acid and mixtures thereof.

The method for preparing a hard coating film includes the following steps: (1) adding a polydimethylsiloxane having a vinyl group or a hexenyl group and a hydrosiloxane to prepare a silicone resin; (2) forming a silicone resin on the substrate layer Coating the composition containing a silicone resin to form a release layer; and (3) coating the release layer with a hard coat resin composition containing a polymer resin having a glass transition temperature of 30 ° C. or more, thereby Forms a hard coat.

Each step will be specifically described below.

Step (1) is a step of preparing a silicone resin by subjecting a polydimethylsiloxane having a vinyl group or a hexenyl group to an addition reaction with a hydrosiloxane.

The specific types, structures, and reaction amounts of the polydimethylsiloxane and the hydrosiloxane are as described above.

Specifically, as shown in Chemical Formula 1, the polydimethylsiloxane may have a vinyl group or a hexenyl group, whereby the vinyl group or the hexenyl group may react with the Si-H group of the hydrosiloxane.

In addition, the reaction can be performed in the presence of a platinum catalyst.

Step (2) is a step of applying a composition containing a silicone resin on a substrate layer to form a release layer.

The base material layer can be prepared by using the raw materials exemplified above and by a general melt extrusion method or the like.

In addition, in order to improve the mechanical strength or optical function, the substrate layer may be uniaxially stretched or biaxially stretched as necessary.

After that, the composition containing the previously prepared silicone resin is coated on the substrate layer, and then a release layer can be formed by heating, drying, and curing.

Step (3) is a step of applying a hard coat resin composition on the release layer to form a hard coat layer.

Specifically, a hard coat resin composition containing a polymer resin having a glass transition temperature of 30 ° C. or higher is applied on the release layer and cured as necessary, so that a hard coat can be prepared.

For coating, spin coating or slit coating, roll coating, screen printing, and applicator methods can be used to apply the hard coating resin composition to a desired coating thickness, for example, at a humidity of 2 to 25 μm. A wet-coating thickness is applied on the release layer. After the coating, the solvent may be removed by heating at a temperature of 50 to 150 ° C. for 1 to 10 minutes.

Curing can be performed by irradiating light having a wavelength of 200 to 450 nm. As a light source used for irradiation, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, an argon laser, etc. may be used, and an X-ray, an electron beam, etc. may be used as needed. The amount of exposure varies depending on the type, mixing amount, and thickness of the dry film of each component of the composition, but when using a high-pressure mercury lamp, it can be 100 mJ / cm ² (at a wavelength of 365 nm) or less.

The hard coat resin composition for coating is obtained by combining the raw material resin (monomer, oligomer, or polymer) exemplified above with a curing agent (heat curing agent or ultraviolet (UV) curing agent) and a solvent for dilution. Mix and mix additives as needed to make.

The hard coat resin composition contains a polymer resin having a glass transition temperature (Tg) of 30 ° C or higher. For example, the hard-coat resin composition may have a glass transition temperature (Tg) of 30 ° C. or higher in addition to the solvent.

In addition, as the solvent, a solvent having a low surface tension is preferably used so that a deviation from the surface tension of the applied release layer can be minimized. For example, as the solvent, alcohols, ketones, or a mixed solvent thereof having a low surface tension can be used. The surface tension of the solvent may be preferably 22 to 30 dyne / cm ² , and more preferably 22 to 26 dyne / cm ² . That is, the hard coat resin composition may contain a ketone, an alcohol, or a mixed solvent thereof having a surface tension of 22 to 26 dyne / cm ² as a solvent.

In addition, the hard coat resin composition may have a surface tension that is lower than the surface tension of the release layer or a difference from the surface tension of the release layer within 10 dyne / cm ² , and more preferably may have a surface tension that is greater than that of the release layer. Has a surface tension that is lower or a difference from the surface tension of the release layer within 3 dyne / cm ² . When the surface tension is within the preferred range, undesired phenomena such as non-coating do not occur, and thus the coating appearance can be better.

In addition, in addition to surface tension, in order to ensure appearance stability, the viscosity of the hard-coat resin composition is preferably adjusted to about 10 to 100 cps. When the viscosity is within the preferable range, defects such as non-coating can be suppressed, and coating can be easily performed on an in-line device.

The present invention will be described in more detail by the following examples. The following examples are only for illustrating the present invention, and the scope of the present invention is not limited to the following examples.

Manufacturing of release film

Example 1-1

10 parts by weight of a polydimethylsiloxane having vinyl or hexenyl groups (manufactured by Dow Corning, LTC750A), 0.2 parts by weight of hydrosiloxane (manufactured by Dow Corning, 7048), and 0.002 parts by weight of a platinum catalyst And the remaining solvent (toluene / methyl ethyl ketone mixed solvent) are mixed and stirred to prepare a total of 100 parts by weight of a release layer resin composition. The release layer resin composition was coated on a polyethylene terephthalate film (PET film) with a thickness of 50 μm by a conventional coating method, and then heated and dried at 150 ° C. for 30 seconds. As a result, a release film having a release layer having a thickness of 0.5 μm was formed on the PET film.

Example 1-2

The same procedure as in Example 1 was performed, except that the coating amount of the release layer resin composition was adjusted to prepare a release film having a thickness of 0.05 μm on the PET film.

Examples 1-3

The same procedure as in Example 1 was performed, except that the coating amount of the release layer resin composition was adjusted to prepare a release film having a thickness of 1 μm on the PET film.

Comparative Example 1-1

10 parts by weight of melamine resin (Aijing Chemicals, AU-126-60), 0.05 parts by weight of p-toluenesulfonic acid as a curing catalyst, and the remaining solvent (toluene / methyl ethyl ketone / isopropanol mixed solvent) are mixed , A total of 100 parts by weight of a release layer resin composition was prepared. In the same manner as in Example 1-1, a release film was prepared using a release layer resin composition.

Preparation of hard coating

Example 2-1

10 parts by weight of an acrylic polyol (Aiking Chemical, AOF-2033), 0.5 parts by weight of an isocyanate compound (Aiking Chemical, AH-2100), and the remaining solvent (methyl ethyl ketone) are mixed and stirred to prepare The hard coating resin composition having a resin solid content concentration other than the solvent of 30% by weight and a Tg of about 30 ° C. The hard coat resin composition is coated on a release layer of a release film by a conventional coating method, and then heated and dried at 120 ° C. for 120 seconds. As a result, a hard coat film having a hard coat layer having a thickness of 2.0 μm was formed on the release layer of the release film.

Comparative Example 2-1

10 parts by weight of an acrylic polyol (polyol, AF-301R, Aiken Chemical), 0.5 parts by weight of an isocyanate (isocyanate, AH-2100, Aiken Chemical) and a solvent (methyl ethyl ketone) are mixed and stirred, so that A hard coat resin composition having a resin solid content concentration other than the solvent of 30% by weight and a Tg of about 20 ° C was prepared. In the same manner as in Example 2-1, a release film was prepared using the hard-coat resin composition.

Comparative Example 2-2

The same steps as in Example 2-1 were repeated, except that propylene glycol monomethyl ether was used as a solvent to prepare a hard coating film.

Comparative Example 2-3

100 parts by weight of an acrylate oligomer (SMP-550A, Kyoeisha Chemical Co., Ltd.), 5 parts by weight of a photopolymerization initiator (Irgacure 184, BASF) and a solvent (methyl ethyl ketone) The hard coating resin composition having a resin solid content concentration of 30% by weight and a Tg of about 20 ° C. was prepared by mixing and stirring. In the same manner as in Example 2-1, a release film was prepared using the hard-coat resin composition.

Comparative Example 2-4

In the same manner as in Comparative Example 2-3, a hard coat layer was formed on the release layer of the release film. A high-pressure mercury ultraviolet lamp was used to irradiate and cure under conditions of an integrated light amount of 300 mJ / cm ² . As a result, a hard coat film having a hard coat layer having a thickness of 2.0 μm was formed on the release layer of the release film.

Evaluation of physical properties

A release film was prepared according to Examples 1-1 to 1-3 and Comparative Example 1-1, and a hard coat layer was formed on these release films according to Example 2-1 and Comparative Examples 2-1 to 2-4, respectively. Thus, a total of 20 hard coating films were prepared by combining 5 hard coatings on 4 release films.

After that, the physical properties were evaluated as shown below, and the results were summarized in Table 1.

Experimental example 1: Evaluation of release force (peeling force)

Apply standard tape (TESA7475) to the release surface of the release film. After being left at room temperature for 30 minutes, the peel test was performed at an angle of 180 ° under the conditions of 0.3 m / min and 25 m / min.

Experimental example 2: Evaluation of adhesion between layers

The hard coating layer attached to the release film was left at room temperature for 30 minutes, and then peeled off at an angle of 180 ° under the conditions of 0.3 m / min and 25 m / min. In addition, when peeling, the presence of a hard coat residue on the release layer was observed with the naked eye.

Experimental Example 3: Appearance Evaluation of Hard Coating

The appearance of the hard coat layer cured after coating on the release layer was observed with the naked eye, and it was confirmed whether there were any coating defects such as uncoated.

O: No coating defect was observed

X: Coating defects such as uncoated are observed

Experimental example 4: Evaluation of print adhesion

10 parts by weight of the evaluation ink (Seiko Advance LTD, 710 Matte Black) and 1.0 part by weight of a curing agent (Seiko Advance, MS-8 Hardner) were mixed and stirred, and the hard coating surface was mixed with 10 It was applied with a thickness of μm, and then heated and dried at 80 ° C. for 30 minutes. Thereafter, a cross hatch cut test was performed on the surface of the printed layer, and whether the printed layer was peeled off was observed with the naked eye.

O: The printed layer is not peeled

X: Peeling of the printed layer occurs

Experimental example 5: Evaluation of storage stability

The hard coating film was cut into a size of 100 mm × 100 mm, and 10 test pieces were prepared. Ten test pieces were laminated on the lower glass plate, and the upper glass plate was covered thereon. Place a 10 kg scale on the upper glass plate for 1 hour. Remove scales and glass plates, and observe with naked eyes whether the hard coat layer is transferred to the surface of the base material layer of the laminated test piece or is peeled off.

O: The hard coat layer is not transferred to other layers and interlayer peeling does not occur

X: The hard coating is transferred to other layers or interlayer peeling occurs

Table 1

As shown in Table 1 above, regarding the hard coat film of the present invention in which the hard coat film of Example 2-1 was formed on the release films of Examples 1-1 to 1-3, the release film was released. The force and surface tension, the surface tension of the hard coating layer, and the interlayer adhesion are within the preferred ranges, and the coating appearance and storage stability have been excellently evaluated.

On the other hand, when a melamine-based release layer was introduced as in Comparative Example 1-1, although the coating appearance of the hard coating layer was good, the interlayer adhesion was high. Therefore, the hard coating layer and the release layer could not be cleaned when peeled And the problem of residual hard coating.

In addition, even when the release films of Examples 1-1 to 1-3 were introduced, when a hard coat layer having a glass transition temperature lower than 30 ° C was formed as in Comparative Examples 2-1, 2-3, and 2-4, interlayer adhesion The force is out of the preferable range, or the print adhesion, storage stability, and the like have been evaluated low. In addition, in Comparative Example 2-2, when coating was performed using a hard coat resin composition having a surface tension outside a preferable range, coating defects such as non-coating occurred.

111‧‧‧first substrate layer
112‧‧‧Second substrate layer
121‧‧‧ the first release layer
122‧‧‧Second release layer
130‧‧‧hard coating
140‧‧‧Adhesive layer

1 to 4 are diagrams illustrating various layer structures of a hard coating film according to an embodiment of the present invention.

111‧‧‧first substrate layer

121‧‧‧ the first release layer

130‧‧‧hard coating

Claims (12)

A hard coating film comprising a structure in which a substrate layer, a release layer, and a hard coat layer are laminated in this order. The release layer includes a polydimethylsiloxane having a vinyl group or a hexenyl group and hydrogen silicon. The silicone resin obtained by the addition reaction of oxane, and the hard coat layer includes a polymer resin having a glass transition temperature of 30 ° C or higher. The hard coating film according to item 1 of the scope of patent application, wherein the hard coating layer has an adhesion of 4 to 10 gf / in to the release layer. The hard coating film according to item 1 of the application, wherein the silicone resin is a vinyl or hexenyl group of the polydimethylsiloxane and the Si-H group of the hydrosiloxane is reacted to form the silicone resin. The hard coating film according to item 3 of the scope of the patent application, wherein the silicone resin is obtained by adding 10 parts by weight of the polydimethylsiloxane and 0.05 to 1.0 parts by weight of the hydrosiloxane. . The hard coating film according to item 4 of the scope of patent application, wherein the polydimethylsiloxane is represented by the following Chemical Formula 1; Chemical Formula 1

In the above Chemical Formula 1, X is a vinyl or hexenyl group, Me is a methyl group, n is an integer of 5 to 100, and m + n is an integer of 1,500 to 15,000. The hard coating film according to item 1 of the scope of patent application, wherein the release layer has a thickness of 0.05 to 1.0 μm. The hard coating film according to item 6 of the scope of patent application, wherein the hard coating layer has a thickness of 0.1 to 30 μm and a surface hardness of 1H or more. The hard coating film according to item 1 of the patent application scope, wherein the hard coating film further comprises a printing layer, an evaporation layer or an adhesive layer on the hard coating layer. A method for preparing a hard coating film, comprising the following steps: (1) adding a polydimethylsiloxane having a vinyl group or a hexenyl group and a hydrosiloxane to an addition reaction to prepare a silicone resin; (2) in Applying a composition containing the silicone resin on a substrate layer to form a release layer; and (3) applying a hard coat layer including a polymer resin having a glass transition temperature of 30 ° C. or more on the release layer The resin composition, thereby forming a hard coat layer. The method for preparing a hard coating film according to item 9 of the scope of application for a patent, wherein the hard coating resin composition has a surface tension lower than that of the release layer or a difference between the surface tension of the release layer and 10 dyne / Surface tension within cm ² . The method for preparing a hard coating film according to item 10 of the application, wherein the hard coating resin composition has a surface tension lower than that of the release layer or a difference between the surface tension of the release layer and 3 dyne / Surface tension within cm ² . The method for preparing a hard coating film according to item 9 of the scope of the patent application, wherein the hard coating resin composition includes a ketone, an alcohol or a mixed solvent thereof having a surface tension of 22 to 26 dyne / cm ² as a solvent.