KR100853470B1 - Oriented polypropylene film for screen protection - Google Patents

Abstract

An oriented polypropylene film for protecting a screen is provided to improve a hardness of a screen protecting film by hard-coating of the surface of the screen protecting film using an UV ray. An oriented polypropylene film for protecting a screen includes a base film(10) and a hard coating layer(20). A primer layer is excluded from the single-layer or at least two-layer base film. A hardening primer resin, a hardening primer resin hardener, a UV hardening resin, a photo-hardening initializer, a resolvent, and an anti-conduction material are included in the UV hard coating layer. The UV(Ultra-Violet) hard coating layer contains at least one element selected from the group consisting of urethane acrylate, epoxy acrylate, polyester acrylate, and polyol acrylate.

Description

OPP film for screen protection {Oriented polypropylene film for screen protection}

The present invention relates to an OPP film for screen protection, and more particularly, to an OPP film for screen protection in which charge resistance, anti-glare, scratch resistance, and the like are imparted to the OPP film.

As a hard protective film used to protect a liquid crystal pole in a conventional liquid crystal display (LCD), a TV monitor, a product coated with a UV film on a polyethylene-terephthalate (PET) substrate film was used. The PET has the advantage that it is excellent in heat resistance and high hardness when UV coating, but the price is expensive.

Accordingly, there has been a movement to replace with oriented polypropylene (ORIENTED POLYPROPYLENE; OPP). The OPP film has an advantage that the price is cheaper than PET, but there is a problem that can not realize a high hardness when UV coating, there has been pointed out that the material of the OPP film itself is not suitable as a hard coating material.

In general, the thickness of the screen protective film was 75 ~ 150㎛ could not use a thin OPP. It is known that OPP film is easy to manufacture a thin thickness (12 ~ 60㎛) due to its excellent elongation, but it is known that it is difficult to produce a relatively thick thickness, and products of more than 70㎛ are not on the market.

Therefore, the present invention is to solve the problems of the prior art using the inexpensive OPP as the base film of the hard coating layer, instead of using expensive PET as the base film of the hard coating layer.

Therefore, the present invention is to provide an OPP film for screen protection that can exhibit the same physical properties as using PET even when the OPP substrate film is included in the UV-curable coating layer without a separate treatment, and applied as a single hard coating layer. The purpose.

As described in detail above, the present invention reinforces stiffness by laminating a thin OPP, solves the problem of film thickness as well as improving product properties, and secures the hardness of the screen protective film by UV hard coating. In addition, the present invention by performing a direct primer and UV curing coating at the same time without a separate primer treatment process is high work efficiency, can lower the manufacturing cost, more effective in terms of risks and environmental pollution by using organic solvents.

 OPP film for screen protection of the present invention for achieving the above object is characterized in that it comprises a hard coating layer.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a hard-coated screen protection OPP film that uses an OPP film other than a PET film that has been used as a screen protection film as a base film and imparts chargeability, anti-glare, and scratch resistance thereto.

The OPP film for screen protection of the present invention is a hard coating layer of the primer layer and the ultraviolet curable coating layer at the same time after mixing the primer composition and the ultraviolet curable coating liquid on the OPP base film (hereinafter, the hard coating layer is a primer layer and an ultraviolet curable coating layer) This means that a single layer is formed.) A film can be formed.

When the primer layer and the ultraviolet curable coating layer are applied in one layer as in the present invention, the coating layer may be applied only to one end surface of the OPP base film or both sides of the OPP film.

In addition, the OPP base film may be laminated with all products having a thickness of 12 to 60 μm and may be arbitrarily adjusted in thickness according to a screen protection use. In the case of laminating and using the OPP base film, it is, of course, possible to apply the coating layer to one or both surfaces.

Diluted with a suitable amount of solvent in order to increase the uniformity of the adhesive coating was applied and the coating method was applied by a method such as roll coating, knife coating, bar coating and dried for 30 seconds in a dry oven.

As can be seen in Figures 1 to 4 below, the screen protective film of the present invention UV UV coating a single-sided / double-sided, OPP film and OPP film to the OPP base film 10, the adhesive film 30 after UV The hard coat layer can be configured in cross section / two sides.

Hereinafter, a coating liquid constituting the UV hard coating layer will be described.

In the composition of the ultraviolet hard coating layer according to the present invention, when the primer layer and the ultraviolet curable resin layer are applied in one layer, the curable primer resin, the curable primer resin curing agent, the ultraviolet curable resin, the photocuring initiator, the solvent and the antistatic agent are included. .

The ultraviolet curable resin according to the present invention is a single or a combination of two or more selected from urethane acrylate, epoxy acrylate, polyester acrylate and polyol acrylate.

Specific examples of the ultraviolet curable resin include dipentaerythritol hexaacrylate (DPHA) di-trimethylolpropane tetraacrylate, (Di-TMPTA, di-trimethylolpropane tetraacrylate), and ethoxylated pentaerythritol tetraacrylate ( PPTTA, ethoxylated (5) pentaerythritol teraacrylate}, and polyfunctional acrylic oligomers include aliphatic urethane diacrylate, reactive chlorinated polyester resin, and epoxy acrylate resin ( Epoxy acrylate resin, Aliphatic urethane triacrylate, Hexafunctional aromatic urethane acrylate oligomer, Chlorinated polyester, Aliphatic urethane diacrylate oligomer diacrylate oligomer), bis The play -A type epoxy resin diacrylate esters (Diacrylate ester of bisphenol-A epoxy resin), and bisphenol -A derivative diacrylate oligomer selected from the group consisting of (Bisphenol A derivative diacrlate oligomer) a functional acrylic monomer.

In addition, tetraethylene glycol dimethacrylate (TTEGDMA, tetraethyleneglycol dimethacrylate), tetraethylene glycol diacrylate (TTEGMA, tetraethyleneglycol diacrylate), tripropylene glycol diacrylate (TPGDA, tripropyleneglycol di-acrylate), polyethylene glycol diacrylate ( PEGDA, polyethyleneglycol (400 ~ 600) diacrylate}, ethyleneglycol dimethacrylate (EGDMA), diethyleneglycol dimethacrylate (DEGDMA), trimethylpropane triacrylate (TMPTA, trimethylpropane triacrylate), Tricyclodocane dimethanol diacrylate (TCDDMDA), propoxylated (2) neopentylglycol diacrylate (NPG2PODA, propoxylated (2) neopentylglycol diacrylate), ethoxylated bisphenol-A (10) Dimethacrylate (BPA (10) EODMA, ethoxylated (10) bisphenol-A dimethacrylate), ethoxylated bisphenol-A (10) diacrylate (BPA (10) EODA, ethoxylated (10) bisphenol-A diacrylate), ethoxylated (3-20) trimethylolpropane triacrylate (TMPEOTA, ethoxylated (3) 20) trimethylolpropane triacrylate), propoxylated (3) glyceryl triacrylate (G3POTA, propoxylated (3) glyceryl triacrylate), propoxylated (6) trimethylolpropane triacrylate ), Pentaerythritol propoxylated triacrylate (PETIA), dipropyleneglycol di-acrylate (DPGDA), hexanediol di-acrylate (HDDA, hexanediol di-acrylate) Methacrylate (HDDMA, hexanediol di-methacrylate), propoxylated glycerol triacrylate (OTA-480), and hydroxyethyl acrylate (HEA) There are two to three functional acrylic monomers selected from the group of gin.

In addition, isobornyl acrylate (IBOA), octyl / decyl acrylate mixture (ODA), 2-phenoxy ethyl acrylate (2-PEA, 2-phenoxy ethyl acrylate), tetra Tetrahydrofurfuryl acrylate (THFA), isbornyl methacrylate (IBOMA), 2-2-ethoxyethoxy ethyl acrylate (EOEOEA), isodecyl acryl Monofunctional acrylic monomers selected from the group consisting of acrylate (IDA, isodecyl acrylate), lauryl acrylate (LA), and lauryl methacrylate (LMA), are not limited thereto.

In addition, the photocuring initiator contained in the composition of the present invention, 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide (2,4,6-trimethylbenzoyl-diphenyl phosphine oxide), hydroxyl-2-methylphenyl-propane- 1-one (hydroxy-2-methylphenyl-propane-1-one), 2-methyl-1- (4-methylthio) phenyl-2-morpholino-propan-1-one (2-methyl-1- (4 -methylthio) phenyl-2-morpholino-propane-1-one), 1-hydroxycyclohexylphenylketone, 4-benzoyl-4-methyldiphenylsulfide, Methyl phenylglyoxylate, isopropylthioxanthone, ethyl-4-dimethylaminobenzoate, tribromomethylphenylsulfone, methyl o-benzoylbenzoate (methyl o-benzoylbenzoate), among which is a low-yellowing type α-hydroxyalkylphenone-based material 1-below At least one compound selected from 1-Hydroxy-cyclohexyl-phenyl Ketone or α, α-dimethoxy-α-hydroxyacetophenone (α, α-Dimethoxy-α-hydroxyacetophenone) .

The content of the photocuring initiator of the present invention is preferably 0.1 to 10% by weight based on the content of the UV-curable resin, when the content is less than 0.1% by weight relative to the UV-curable resin content, the reactivity is slow, while exceeding 10% When the reactivity increases, but the surface hardness is lowered, there is a problem that the crack of the coating film occurs.

The solvent of the present invention is used in the sense of the reaction diluent, the content is preferably 25 to 400% by weight relative to the content of the ultraviolet curable resin, 20 to 80% in terms of solid content. If the content of the UV curable resin is less than 25% by weight, the viscosity is high, so that the thickness of the coating becomes thick and the adhesion with the substrate is low.

The solvent is methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, pentyl alcohol, ethyl cellosolve, benzene, toluene, xylene, ethylbenzene, cyclohexane, ethylcyclo One kind or two or more kinds selected from the group consisting of hexane, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, tetrahydrofuran and water can be used in combination.

The antistatic agent of the present invention may impart antistatic properties by using a hybrid acrylic monomer in which charge transfer of ions and electrons occurs at the same time, and the content thereof is preferably 1 to 7% by weight relative to the total UV curable resin content. Specific examples of the antistatic agent include specific examples of the antistatic agent, such as tin dope indium oxide, antimony dope tin oxide, tin oxide, zinc antimonate, and antimony pentoxide.

The curable primer resin of the present invention preferably uses a polyester-urethane, a vinyl polyol-based resin, or an acrylic-based resin, but is not limited thereto. The amount of the curable primer resin is preferably contained in 10 to 90% by weight relative to the content of the ultraviolet curing liquid containing the ultraviolet curing resin, photocuring initiator, solvent and antistatic agent. If the content is less than 10% by weight compared to the content of the UV curing liquid, adhesion to the base film may be a problem, when the content exceeds 90% by weight is not preferred because the hardness of the coated hard coating layer is lowered.

In addition, polyisocyanate is used as a curing agent of the curable primer resin of the present invention, preferably aliphatic diisocyanate, and most preferably alicyclic diisocyanate. The content of the curing agent is preferably 2 to 10% by weight relative to the curable primer resin content.

When preparing the hard coating layer composition having the composition as described above, it is effective to mix the curable primer resin and the ultraviolet curable resin and then to mix the curable primer resin curing agent before using the coating liquid to ensure storage. Pot life after mixing the said curable primer resin hardener to a composition is 5 to 8 hours.

Meanwhile, as the base film of the present invention, a double-sided corona-treated stretched polypropylene (ORIENTED POLYPROPYLENE; OPP) film is used, and the thickness thereof may be used as long as it is 12 to 60 μm, but the protective film for protection of the liquid crystal in the future. It is most preferable that it is 60 micrometers.

When the composition is applied to the OPP, methods such as roll coating, dip coating, knife coating, bar coating, and spin coating are used.

The applied film is then hot air dried in an oven at 40 to 60 ° C. for 10 to 60 seconds.

The hot-air dried film is ultraviolet cured by irradiating a light source selected from the group consisting of a halogen lamp, a high pressure mercury lamp, and a metal halide lamp. Irradiation time and intensity during UV curing were 350 mJ / cm ² , Although it is preferable that it is 120 W / cm <2> or more and time 10sec, It is not limited to this.

The OPP film for the protective film including the hard coating layer of the present invention manufactured according to the above process does not include a curable primer layer, so that the process may be shortened to reduce manufacturing costs and include a curable primer layer. Even if the physical properties of the final OPP film can be maintained at the same level as the existing film.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

Example 3

First, according to the composition shown in Table 1 was mixed with the curable primer layer composition solution and ultraviolet curable resin solution to prepare a solution for coating the hard coat layer. The coating liquid was applied to one surface of a 60 µm thick double-sided corona treated OPP film (Philmax, product name BT 60) using a 0.05 mm Meyer bar.

The coated film was dried at 50 ° C. in DRY OVEN for 20 seconds, and then irradiated with 350 mJ / cm 2 and 120 W / cm 2 using mercury or metal lamps to cure ultraviolet rays. The coating film thickness of the final hard coat layer formed in this way was 2 micrometers, respectively.

Examples 4-6

In Example 4 to prepare a solution for applying a hard coating layer while varying the content of the curable primer resin as in the composition of Table 1, to prepare an OPP film with a hard coating layer in the same manner as in Example 3. Its coating film thickness was 2 micrometers, respectively.

In addition, in Examples 5 and 6 to prepare a solution for applying a hard coating layer while changing the content of the curable primer resin as shown in Table 1, instead of applying to one side of the OPP base film in Example 3 OPP base film Except for coating on both sides of the OPP film was prepared in the same manner as in Example 3, the hard coating layer was formed. Its coating film thickness was 2 micrometers, respectively.

Example 7

Optionally, a thin stretched polypropylene (ORIENTED POLYPROPYLENE (OPP)) was laminated using an adhesive. In the present invention, the OPP film used for the paper used DGT 352 of Daelim Industrial, which was treated with double-sided corona, and has a thickness of 35 μm.

After diluting the adhesive of the room temperature curing type two-component type in a solvent, the coating film was dried to have a thickness of 1 to 2 μm, and then two OPPs were laminated.

To prepare a composition for a hard coating layer to have a composition as shown in Table 1. A 0.05 mm Mayer bar was used to apply one surface of an untreated OPP film (Filmmax product name BT 60, laminated Daelim Industrial DGT) to a thickness of 60 μm. After drying for 20 seconds at 50 ℃, DRY OVEN irradiated with ultraviolet (350mj / cm ² , 120W / cm ² ) The coating film thickness of the hard coating layer formed in this way was 2㎛.

Example 8

Except for applying a hard coating layer on both sides of the two laminated OPP substrate film in Example 7, the screen protection OPP film was prepared in the same manner as in Example 7, the coating film thickness of the final hard coating layer 4 micrometers.

Comparative Example 1

As in Table 1, in the composition of Example 3, an ultraviolet curable resin composition containing no curable primer resin and a curing agent thereof was prepared.

* The prepared resin composition was applied to an untreated OPP film having a thickness of 60 μm using a Mayer bar of 0.05 mm, dried at 50 ° C. for 20 seconds, and then irradiated with ultraviolet rays. (350mj / cm ² , 120W / cm ² ) The coating film thickness of the ultraviolet curable resin layer thus formed was 2 μm.

Comparative Example 2

Except for applying the composition of Comparative Example 1 on both sides of the OPP film, an OPP film coated with an ultraviolet curable resin layer was prepared in the same manner as in Comparative Example 1, the coating film thickness was 4㎛.

The coating film thickness of the OPP films prepared in Examples and Comparative Examples was measured using a Digimatic Micrometer MDC-25PJ, the surface resistance was measured using a TRUSTAT WORKSURFACE TESTER MODEL ST-3, pencil hardness was Staedtler Mars Gmbh & Co . Adhesion was measured using KG, and adhesive force was measured by 5 times debonding test after 100 grid crosscutting at 1 mm intervals using 3M cello tape, and high temperature and high humidity test was performed after standing in a thermo-hygrostat at 60 ℃, 90% x 24HR. The appearance was observed by visual observation of curl generation and film transparency, and the results are shown in Table 2 below.

As can be seen in Table 2, in the case of the embodiment in which only the hard coating layer, which is a single layer of the primer layer and the UV curable resin layer, is not applied to the OPP base film separately, as in the present invention, Comparative Examples 1 and 2 As described above, when the substrate is not treated with the curable primer resin solution, the UV-curable resin adhesive strength is lowered, and the coating film is broken, which is not preferable.

In addition, as the content of the curable primer resin increases, the adhesion between the coating solution and the substrate OPP is excellent, but the hardness tends to decrease. In addition, when the content of the monofunctional group is increased in the UV-curable resin, the hardness is lowered, and when the content of the polyfunctional group is increased, the hardness is increased but the adhesive strength is lowered.

As in the embodiment of the present invention, in terms of work efficiency and cost, it is preferable to apply a single layer of the hard coat layer.

1 and 2 are OPP films for screen protection, each of which is coated with a hard coating layer on one side and both sides of the OPP base film according to the present invention,

3 and 4 shows the OPP film for screen protection after laminating the OPP base film according to the present invention, the hard coating layer is applied to one side and both sides of the base film, respectively.

<Short description of drawing symbols>

1, 2, 3, 4: OPP film for screen protection according to the present invention

10: OPP base film, 20: hard coating layer

30: adhesive

Claims (13)

It does not include a separate primer layer, and contains 1 to 10% by weight of a photocuring initiator, and 1 to 7% by weight of an antistatic agent, based on the UV-curable resin content on one or two or more layers of one or more layers of the bonded base film. OPP film for screen protection comprising only a hard coating layer coated with a coating liquid containing 10 to 90% by weight of the curable primer resin, and 2 to 10% by weight of the curable primer resin curing agent relative to the amount of the curable primer resin . delete delete delete The OPP film for screen protection according to claim 1, wherein the curable primer resin is a polyester-urethane resin. The OPP film for screen protection according to claim 1, wherein the ultraviolet curable resin is at least one selected from urethane acrylate, epoxy acrylate, polyester acrylate and polyol acrylate. 7. The screen according to claim 1 or 6, wherein the ultraviolet curable resin is at least one polyester acrylate selected from the group consisting of a monofunctional acrylic monomer, a 2,3-functional acrylic monomer and a polyfunctional acrylic monomer. Protective OPP Film. delete delete delete 10 to 90% by weight of the curable primer resin relative to the content of the ultraviolet curable resin composition containing 1 to 10% by weight of the photocuring initiator, and 1 to 7% by weight of the antistatic agent based on the content of the ultraviolet curable resin, and the curable primer resin content Preparing a coating solution for forming a hard coating layer containing 2 to 10 wt% of a curable primer resin curing agent, Forming a hard coat layer by coating the coating liquid on one or both surfaces of the base film, Drying the applied film, and Method of producing a screen protection OPP film comprising the step of curing by irradiating the dried film with ultraviolet light. delete 12. The method of claim 11, wherein the hard coating layer is coated by a bar coating method.

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