KR20200000134A - Hard Coating Film and Method of Preparing the Same - Google Patents

Abstract

The present invention relates to a hard coating film and a method for manufacturing the same. Specifically, provided are a hard coating film which is a film used for an exterior material of a portable electronic device, has excellent scratch resistance and flexibility at the same time, and especially, can overcome a lifting phenomenon on an edge side when a protection film is stacked; and a method for manufacturing the hard coating film.

Description

Hard Coating Film and Method for Preparing the Same {Hard Coating Film and Method of Preparing the Same}

The present invention relates to a hard coat film and a method of manufacturing the same.

In general, important commercial products, including optically functional products such as windows of various electronics, touch screens for computers, lenses, automotive sunroofs, optical screens, light guide plates and LED faceplates, have been heavily used for glass, but they are heavy and fragile. The defect rate was considerably high when processing the product.

To replace this, thermoplastic and thermosetting polymers are used, which have been used to form various structures characterized by high hardness and high light transmittance.

However, many of these thermoset and thermoplastic polymers have excellent stiffness, dimensional stability, transparency and impact resistance, but are poor in abrasion resistance, heat resistance, solvent resistance and chemical resistance, so that the structures made from these polymers have scratches, wear, hardness compared to glass. There is a problem in the back.

In particular, the film used for the exterior material of the portable electronic device is required various properties such as wear resistance, scratch resistance, solvent resistance, chemical resistance, weather resistance, heat resistance, flex resistance.

However, it is difficult to satisfy the scratch resistance and the bendability at the same time because the two characteristics are opposite to each other having the scratch resistance and the bendability.

In addition, recently, as the protective film has an edge on the edge of the portable electronic device has a bending characteristic, the research and development is actively made to solve this problem.

In this regard, Korean Patent Application No. 2008-0049096 discloses a technology used as a protective film for portable electronic devices as a protective film having a structure including a base film, but the lifting of the edge side may still be a problem. There is an urgent need for technology development to solve this problem.

The present invention is to provide a hard coating film and a method of manufacturing the same, which has excellent scratch resistance and bendability at the same time as the film used in the exterior material of the portable electronic device, in particular to solve the lifting phenomenon of the edge side when the protective film is laminated. .

One embodiment of the present invention includes a release layer and a hard coating layer formed on any one surface of the release layer, the release layer includes a polyurethane dispersion (PUD), a crosslinking agent and a chain extender, the hard The coating layer is to provide a hard coating film comprising a multifunctional acrylate-based polymer and an aliphatic urethane acrylate-based polymer.

The water-dispersed urethane is characterized in that the glass transition temperature is -80 ℃ to -40 ℃.

The crosslinking agent may be at least one selected from diols and imides, and the chain extender is at least one selected from triols, tetraols, and diamines.

The release layer is characterized in that it comprises 5 to 10 parts by weight of the crosslinking agent and 5 to 10 parts by weight of the chain extender based on 100 parts by weight of the water-dispersed urethane.

The hard coating layer is characterized in that it comprises 20 to 100 parts by weight of an aliphatic urethane acrylate polymer based on 100 parts by weight of the multifunctional acrylate polymer.

Another embodiment of the present invention is a step of forming a release layer by wet coating (Wet Coating) a release composition comprising a polyurethane dispersion (PUD), a crosslinking agent and a chain extender on a base film (S1). ; Forming a hard coating layer by wet coating a hard coating composition including a polyfunctional acrylate polymer and an aliphatic urethane acrylate polymer on one surface of the release layer (S2); And after laminating a protective film on the formed hard coating layer, and to provide a method of manufacturing a hard coating film comprising the step (S3) of removing the base film.

The crosslinking agent may be at least one selected from diols and imides, and the chain extender is at least one selected from triols, tetraols, and diamines.

The release composition is characterized in that 5 to 10 parts by weight of the crosslinking agent and 5 to 10 parts by weight of the chain extender based on 100 parts by weight of the urethane.

The hard coating composition is characterized in that it comprises 20 to 100 parts by weight of an aliphatic urethane acrylate polymer based on 100 parts by weight of the multifunctional acrylate polymer.

The hard coating film and the manufacturing method thereof according to the present invention is a film used for the exterior material of a portable electronic device, and has excellent scratch resistance and bendability at the same time. In particular, there is no base film when laminating a protective film, thus lifting the edge of the edge. I can solve it.

According to one embodiment of the present invention, a release layer and a hard coating layer formed on any one surface of the release layer, the release layer comprises a polyurethane (Poly Urethane Dispersion; PUD), a crosslinking agent and a chain extender, The hard coating layer is to provide a hard coating film comprising a polyfunctional acrylate-based polymer and aliphatic urethane acrylate-based polymer.

Conventional hard coating film has a base film, there was a problem that the lifting phenomenon occurs on the edge of the protective film when laminated to the protective film.

Hard coating film according to an embodiment of the present invention does not have a base film, it can prevent the problem that the edge of the protective film is lifted when the protective film is laminated.

Specifically, the hard coating film according to the prior art has a thickness of the base film for coating the hard coating layer is approximately 75㎛ or more, the thickness of this hard coating film is about 80㎛. In addition, the bending of the base film, for example, the PET film itself is not good, there is a problem that the lifting phenomenon occurs in the edge portion of the base film over time because the adhesive strength is not high when laminated with a cell phone glass protective film .

Since the hard coating film does not require a base film while including a release layer and a hard coating layer, it is also excellent in bending (bending) and can also prevent the lifting problem of the conventional problem, the release layer has a high flexibility of the film The scratch resistance can be simultaneously improved by introducing a hard coat layer while improving the bendability.

The release layer preferably includes a water urethane (Poly Urethane Dispersion (PUD)), a crosslinking agent and a chain extender.

The water-dispersed urethane has a glass transition temperature of -80 ° C to -40 ° C, preferably -50 ° C to -40 ° C. When the glass transition temperature is less than -80 ℃, the glass transition temperature is too low, the number of unreacted reactors and the flexibility can be improved due to this, but it is difficult to peel the base film from the release layer in the process of removing the base film due to the high temperature release force. And, if it exceeds -40 ℃ there is a problem in that the hardness is lowered flexibility (Flexiblility).

The water-dispersed urethane is usually made by polymerizing isocyanate and alcohol, such as synthesizing urethane, and means a liquid in which the particles are dispersed in water.

There is an unreacted group in such a water-dispersed urethane, in the present invention is to cross-link or extend the chain of a water-dispersed urethane having an unreacted group, including the cross-linking agent and a chain extender.

The crosslinking agent is at least one selected from diols and imides.

The diol is at least one selected from ethylene glycol, ethylene glycol, propylene glycol, 1, 4-butanediol, and the like.

The imide may include carbodiimide, but is not limited thereto.

The chain extender is at least one selected from Triol, Tetraol, and diamine.

The triol is at least one selected from glycerin and trimethyol propane, but is not limited thereto.

The tetraol is at least one selected from pentaerythritol and oxypropylated ethylene diamine, but is not limited thereto.

The diamine is at least one selected from ethylene diamine, hexamethylenediamine, and m-phenylenediamine, but is not limited thereto.

The release layer preferably contains 5 to 10 parts by weight of the crosslinking agent and 5 to 10 parts by weight of the chain extender based on 100 parts by weight of the water-dispersed urethane.

When the content of the crosslinking agent and the chain extender is less than 5 parts by weight, respectively, the effect of crosslinking and the chain extension is not great, and thus there is no effect on the glass transition temperature, and the content of the crosslinking agent and the chain extender exceeds 10 parts by weight, respectively. In this case, there is a problem in that the degree of curing is too high, thereby increasing the Tg, thereby lowering the flexibility.

The hard coating layer preferably includes a polyfunctional acrylate polymer and an aliphatic urethane acrylate polymer.

The multifunctional acrylate polymer includes at least 5 to 6 functional groups, and may include any one or more selected from Dipentaerythritol Hexaacylate, Dipentaerythritol Pentaacrylate, Pentaery Tetraacrylate, and Di-Trimethylopropane Tetraacrylate.

The hard coating layer preferably contains 20 to 100 parts by weight of an aliphatic urethane acrylate polymer based on 100 parts by weight of the multifunctional acrylate polymer.

When the content of the aliphatic urethane acrylate polymer is less than 20 parts by weight compared to the polyfunctional acrylate polymer, the scratch resistance of the hard coating layer is excellent, but the flexibility is low, so that cracks are formed in the hard coating layer during the peeling process of the substrate layer. There is a problem that occurs, if it exceeds 100 parts by weight scratch resistance is too bad there is a problem that can not be used as a protective film.

According to another embodiment of the present invention, the step of forming a release layer by wet coating (Wet Coating) a release composition comprising a polyurethane dispersion (PUD), a crosslinking agent and a chain extender on a base film ( S1); Forming a hard coating layer by wet coating a hard coating composition including a polyfunctional acrylate polymer and an aliphatic urethane acrylate polymer on one surface of the release layer (S2); And after laminating a protective film on the formed hard coating layer, and to provide a method of manufacturing a hard coating film comprising the step (S3) of removing the base film.

In detail, the release composition comprising a polyurethane dispersion (PUD), a crosslinking agent, and a chain extender is wet coated on a base film to form a release layer (S1).

Polyurethane Dispersion (PUD), crosslinking agent and chain extender included in the release composition is the same as described above.

The release composition preferably contains 5 to 10 parts by weight of the crosslinking agent and 5 to 10 parts by weight of the chain extender based on 100 parts by weight of the urethane. The related content is the same as described above.

On one surface of the formed release layer, a hard coating composition including a polyfunctional acrylate polymer and an aliphatic urethane acrylate polymer is wet coated to form a hard coating layer (S2).

The content related to the polyfunctional acrylate polymer and the aliphatic urethane acrylate polymer included in the hard coating composition is the same as described above.

The hard coating composition may include 20 to 100 parts by weight of an aliphatic urethane acrylate polymer based on 100 parts by weight of the multifunctional acrylate polymer. The related content is the same as described above.

After laminating the protective film on the formed hard coating layer, the base film is removed (S3).

The hard coating film prepared in the manufacturing method does not have a base film to prevent the edge lifting phenomenon of the protective film, which is a problem of the conventional hard coating film, and the release layer is high in flexibility while improving the flexibility of the film The introduction of a hard coat layer can simultaneously improve scratch resistance.

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

Example

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.

< Example  1>

Release composition preparation

Polyurethane Dispersion (PUD) (KU-5901, dry weight) based on 100 parts by weight of the cross-linking agent (Carbodiimide-based, V02-L2, Nisshinbo chemical) 7 parts by weight and chain extender (ethylene diamine (EDA) Sigma-aldruch 7 parts by weight of the solution was added and dissolved sufficiently to prepare a composition having a solid content of 35wt%.

Hard coating (HC) Composition Preparation

Based on 100 parts by weight of the multifunctional acrylate polymer (CN8885NS, Satomer), 25 parts by weight of aliphatic urethane acrylate polymer (CN9893, Satomer) and 3 parts by weight of photoinitiator (Irgacure184) were added, followed by sufficient dissolution to prepare a 20 wt% solid composition. It was.

Hard coating  Film manufacturing

Wet coating the release composition to a thickness of 15 μm on an untreated PET film (Kolon, CD901), dried in a 120 ° C. oven for 3 minutes to form a release layer, and then a hard coating composition on the upper surface of the formed release layer. Wet Coating to a thickness of 3㎛, dried for 3 minutes in an oven at 100 ℃ after mounting a type-D bulb to the ultraviolet irradiation device (Fusion company) to irradiate with an exposure dose of 500mJ / ㎠ to form a hard coating layer.

Then, after laminating a protective film (UCF-MP2, oil phase) on the top of the formed hard coating layer (De Lamination) to prepare a hard coating film.

< Comparative example  1>

Except that the release composition was carried out in Example 1 as described below was carried out in the same manner.

Release composition preparation

Acrylic polymer (A-21, Dow) was sufficiently dissolved in a solvent toluene to prepare a composition of 35wt% solids.

< Comparative example  2>

Except that the release composition was carried out in Example 1 as described below was carried out in the same manner.

Release composition preparation

PUD (KU-5901, dry) was sufficiently dissolved in water to prepare a composition with a solid content of 35wt%.

< Comparative example  3>

Except that the release composition and the hard coating composition in Example 1 was carried out as follows.

Release composition preparation

Acrylic polymer (A-21, Dow) was sufficiently dissolved in a solvent toluene to prepare a composition of 35wt% solids.

Hard coating  Composition preparation

10 parts by weight of urethane acrylate (CN8885NS, Satomer) and 3 parts by weight of photoinitiator (Irgacure184) were added based on 100 parts by weight of aliphatic urethane acrylate (CN9893, Satomer) to prepare a composition having a solid content of 20wt%.

< Comparative example  4>

Except for carrying out the release composition and the hard coating composition in Example 1 as described below.

Release composition preparation

Acrylic polymer (A-21, Dow) was sufficiently dissolved in the solvent toluene to prepare a composition of solid content of 35wt%.

Hard coating  Composition preparation

Aliphatic urethane acrylate (CN9893, Satomer) based on 100 parts by weight of urethane acrylate (CN8885NS, Satomer) 120 parts by weight, photoinitiator (Irgacure184) 3 parts by weight was added and dissolved completely to prepare a 20wt% composition.

<Measurement method>

1. Scratch resistance: Using abrasion friction tester, abrasion friction No # 001 was attached to the equipment, weighed 1.5Kg, and checked the presence of scratches after rubbing the surface of HC film more than 11 times.

2. Flexibility (R): As a test method for making Menderrel Flexibility, check the presence of crack when bending the film on the iron bar of 2R ~ 22R and read the R value of the bar when no crack appeared.

3. Room temperature release force (g): Peel Tester was used to measure the force falling PET film.

Release layer thickness Hard Coating Layer Thickness Release layer component Presence of crosslinking agent and chain extender Example 1 15 μm 3 μm PUD U Comparative Example 1 15 μm 3 μm Acyl radish Comparative Example 2 15 μm 3 μm PUD radish Comparative Example 3 15 μm 3 μm Acyl radish Comparative Example 4 15 μm 3 μm Acyl radish

Scratch resistance Flexibility® Room temperature release force (g / 25mm) Example 1 OK 3R 5 Comparative Example 1 OK 3R 800 Comparative Example 2 OK 3R 500 Comparative Example 3 OK 13R 750 Comparative Example 4 NG 3R 760

As shown in the table, it was found that Example 1 has good bending property, no scratch resistance, and low release temperature at room temperature, thereby making it possible to produce a flexible hard-coated (HC) film because it is easily released during delamination. On the contrary, in Comparative Examples 1 to 4, the release layer and the hard coating layer did not satisfy the components of the present invention, and it was found that the scratch resistance, the bendability, and the room temperature release force were not satisfied.

From this, when the hard coating film according to the present invention is applied as a film used in the exterior material of portable electronic devices, it has excellent scratch resistance and bendability at the same time, in particular, the effect of solving the lifting phenomenon of the edge side when laminating the protective film It can be seen that there is.

Claims (9)

It includes a release layer and a hard coating layer formed on any one surface of the release layer,
The release layer comprises a poly urethane dispersion (PUD), a crosslinking agent and a chain extender,
The hard coating layer is a hard coating film comprising a polyfunctional acrylate-based polymer and aliphatic urethane acrylate-based polymer. The hard coating film of claim 1, wherein the water-dispersed urethane has a glass transition temperature of -80 ° C to -40 ° C. The method of claim 1, wherein the crosslinking agent is at least one selected from diols and imides, and the chain extender is at least one selected from triols, tetraols, and diamines. Hard coating film made with. The hard coat film of claim 3, wherein the release layer comprises 5 to 10 parts by weight of the crosslinking agent and 5 to 10 parts by weight of the chain extender based on 100 parts by weight of the water-dispersed urethane. The hard coating film of claim 1, wherein the hard coating layer comprises 20 to 100 parts by weight of an aliphatic urethane acrylate polymer based on 100 parts by weight of the multifunctional acrylate polymer. Forming a release layer by wet coating a release composition including a poly urethane dispersion (PUD), a crosslinking agent, and a chain extender on a base film (S1);
Forming a hard coat layer by wet coating a hard coating composition including a polyfunctional acrylate polymer and an aliphatic urethane acrylate polymer on one surface of the release layer (S2); And
After laminating the protective film on the formed hard coating layer, the method of manufacturing a hard coating film comprising the step (S3) of removing the base film. The method of claim 6, wherein the crosslinking agent is at least one selected from diols and imides, and the chain extender is at least one selected from triols, tetraols, and diamines. Method for producing a hard coat film. The method of claim 7, wherein the release composition comprises 5 to 10 parts by weight of the crosslinking agent and 5 to 10 parts by weight of the chain extender based on 100 parts by weight of the urethane. The method of claim 6, wherein the hard coating composition comprises 20 to 100 parts by weight of an aliphatic urethane acrylate polymer based on 100 parts by weight of the multifunctional acrylate polymer.