KR101375948B1 - Adhesive protective film - Google Patents

Abstract

The present invention relates to an adhesive protective film, more specifically, a base film; An antistatic layer formed on the base film; And an adhesive layer formed on the antistatic layer, wherein the base film has a corona treatment or a primer layer formed on a surface on which the antistatic layer is formed, and the thickness of the antistatic layer is 10 nm to 1,000 nm, The thickness is 5㎛ ~ 30㎛ provides an adhesive protective film. According to the present invention, there is no transition phenomenon such as an antistatic agent and an adhesive, in particular, the adhesion between the base film and the antistatic layer is excellent, and antistatic properties such as surface resistance and peeling charging are improved.

Description

Adhesive Protective Film {ADHESIVE PROTECTIVE FILM}

The present invention relates to an adhesive protective film that protects the surface, and more particularly, to an adhesive protective film having excellent properties such as surface resistance and peeling charge, without a transition phenomenon such as an adhesive.

In general, an adhesive protective film for protecting a surface is attached to an electronic component or the like. Such adhesive protective films are particularly suitable for use in display panels such as LCD panels (PDPs), plasma display panels (PDPs), etc., which form display devices such as mobile phones, computer monitors, TVs, and advertisement boards. Soaring.

The adhesive protective film protects the surface of the adherend from external force or contamination. The adhesive protective film generally has a laminated structure including a base film and an adhesive layer formed on the base film.

When peeling the pressure-sensitive adhesive protective film from the adherend such as a display panel, a polarizing plate, a semiconductor, a wiring board, large and small static electricity is generated depending on the type of the adhesive. At this time, the generated static electricity damages the adherend or introduces fine foreign matter such as dust, sila and the like to adhere to the adherend. Due to static electricity, the adherend may be electrically damaged and may not exhibit its existing characteristics or may be physically damaged by foreign matter contamination.

In order to prevent the static electricity as described above, an antistatic agent is applied to the adhesive protective film. Antistatic agents are generally used conductive polymers, metal salts and ionic liquids. For example, there has been attempted an adhesive protective film in the form of incorporating an antistatic agent into the adhesive layer in order to prevent static electricity. In this case, however, when attached for a long time or stored under a special condition, the antistatic agent mixed in the adhesive layer elutes to the adhesive layer surface and contaminates the surface of the adherend, causing a cosmetic or functional problem. As another example, a technique has been attempted to form a separate antistatic layer on the outer surface of the base film, that is, on the surface opposite to the surface on which the adhesive layer is formed. However, in this case, the antistatic ability is poor.

Therefore, in recent years, the technique of forming an antistatic layer between a base film and an adhesion layer is mainstream. For example, Japanese Patent Laid-Open Publication No. JP2003-027019, Japanese Laid-Open Patent Publication JP2006-126429, and Korean Laid-Open Patent Publication No. 10-2006-0066401 and the like have been described.

However, since the antistatic layer is formed between the base film and the pressure-sensitive adhesive layer, the pressure-sensitive adhesive protective film disclosed in the preceding patent documents does not elute the surface of the pressure-sensitive adhesive layer, but the adhesion between the base film and the antistatic layer is weak. There is a problem. In addition, there is a problem that the transition phenomenon of the pressure-sensitive adhesive occurs, and the antistatic properties such as surface resistance and peeling charging are not good.

Japanese Laid-Open Patent JP2003-027019 Japanese Laid-Open Patent JP2006-126429 Republic of Korea Patent Publication No. 10-2006-0066401

Accordingly, the present invention is to provide an adhesive protective film that is excellent in adhesion between the base film and the antistatic layer, and excellent in antistatic properties such as surface resistance and peeling charge, without transition phenomenon such as an antistatic agent and an adhesive. have.

According to an aspect of the present invention,

A base film;

An antistatic layer formed on the base film; And

Including an adhesive layer formed on the antistatic layer,

The base film is corona treated or a primer layer is formed on the surface on which the antistatic layer is formed,

The antistatic layer has a thickness of 10 nm to 1,000 nm,

The adhesive layer has a thickness of 5 μm to 30 μm to provide an adhesive protective film.

According to a preferred embodiment, the primer layer is formed by coating an acrylic resin or polyester resin, the thickness of the antistatic layer is 50nm ~ 300nm, the thickness of the adhesive layer is preferably 15㎛ ~ 25㎛.

In addition, the antistatic layer may include polyethylene dioxythiophene (PEDOT) as an antistatic agent, and the adhesive layer may include an acrylic adhesive having a hydroxyl group.

According to the present invention, there is no transition phenomenon such as an antistatic agent and an adhesive, and in particular, the adhesion between the base film and the antistatic layer is excellent, and the antistatic property such as surface resistance and peeling charging is excellent.

1 is a cross-sectional view of an adhesive protective film according to a first aspect of the present invention.
2 is a cross-sectional view of the adhesive protective film according to the second aspect of the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. The accompanying drawings are cross-sectional views illustrating exemplary forms of the adhesive protective film according to the present invention.

1 and 2, the adhesive protection film according to the present invention is formed on a base film 10, an antistatic layer 20 formed on the base film 10, and the antistatic layer 20. The adhesive layer 30 is included. That is, the antistatic layer 20 is formed between the base film 10 and the adhesive layer 30.

In addition, the adhesive protective film according to the present invention may further include a release film 40 formed on the adhesive layer 30. The release film 40 is peeled off when attached to the adherend. At this time, the release film 40 includes a release substrate 42 and a release layer 44 formed on the release substrate 42, as shown in the figure.

In the present invention, the adherend is not limited as long as the adhesive protective film according to the present invention is applied. The adherend may be, for example, an LCD panel (Liquid Crystal Display Panel) or PDP (Plasma Display Panel) constituting an electronic component, more specifically, a display device such as a mobile phone, a computer monitor, a TV, and various billboards. Display panels such as; Optical elements such as polarizing plates; And various semiconductors, wiring boards, and the like.

The base film 10 is not limited as long as it has a bearing force. The base film 10 may be selected from, for example, paper, fiber sheet (woven or nonwoven), plastic film, or the like. According to a preferred embodiment, the base film 10 is selected from a plastic film and may be selected from a film comprising at least one resin selected from, for example, polyester based, polyolefin based, polyimide based and the like.

The base film 10 may be, for example, polyethylene terephthalate (PET), polybutylene terephthalate (PBT; Polybutyleneterephthalate), polyethylene naphthalate (PEN; Polyethylenenaphthalate), or polybutylene naphthalate (PBN). ), A film including one or more resins selected from the group consisting of polyethylene (PE; polyetylene), polypropylene (PP; Polypropylene), polyimide, and the like may be used, but is not limited thereto.

In addition, the base film 10 is not particularly limited, but may have a thickness of 12 μm to 100 μm. For example, the base film 10 is a film for optics which is used a lot for electronic components, and it is preferable to use a polyester film having a thickness of 25 μm to 75 μm.

At this time, the base film 10 is surface-treated at least on the surface on which the antistatic layer 20 is formed, that is, the surface in contact with the antistatic layer 20. Specifically, the base film 10 has a corona treatment or a primer layer 12 formed on the surface on which the antistatic layer 20 is formed. By such a surface treatment, the adhesion with the antistatic layer 20 is improved. Preferably, the primer layer 12 is formed as shown in FIG.

The primer layer 12 is formed by coating an adhesive resin, the thickness is not limited, but the primer layer 12 may have a thickness of, for example, 5nm ~ 30㎛. The primer layer 12 is preferably formed by coating one or more resins selected from acrylic resins, urethane resins, polyester resins, and the like. The primer layer 12 is more preferably formed by coating an acrylic resin or a polyester resin among the above resins. According to the present invention, when the primer layer 12 is formed by coating an acrylic resin or a polyester resin, the base film 10 and the antistatic layer 20 have very good adhesion.

The antistatic layer 20 includes an antistatic agent. The antistatic layer 20 specifically includes a binder resin and an antistatic agent. The antistatic layer 20 is more specifically formed by coating an antistatic composition comprising a binder resin and an antistatic agent.

The binder resin is used for the interlayer adhesion between the antistatic agents as well as the interlayer adhesion, that is, the base film 10 and the antistatic layer 20, and the interlayer adhesion between the antistatic layer 20 and the adhesive layer 30. The binder resin is not limited as long as it has adhesive force. The binder resin includes a water-soluble or water-insoluble (organic solvent type) and the like, preferably a high molecular compound having one or more functional groups selected from, for example, acrylic group, urethane group, epoxy group, amide group, hydroxyl group and silane group It can be used by mixing two or more. For example, the binder resin may use one or more selected from acrylic resins (such as polyacryl and polyacrylates), polyurethanes, polyepoxys, polyamides, polyesters, ethylvinylacetates, polysiloxanes, copolymers thereof, and the like. However, it is not limited by these.

The antistatic agent is not particularly limited as long as it has antistatic performance. The antistatic agent may be used, for example, at least one selected from the group consisting of a conductive polymer, a metal salt having a metal ion, an ionic liquid, a carbon material, a surfactant, and the like.

The conductive polymer is polyethylene dioxythiophene (PEDOT, Polyethylene dioxythiophene), polyacetylene (Polyacetylene), poly (p-phenylene vinylene) (Poly (p-phenylene vinylene)), poly (p-phenylene) (Poly ( p-phenylene)), poly (thienylene vinylene), polythiophene, polyaniline, polyisothianaphthene, polypyrrole and polypyrrole One or more selected from the group consisting of poly (p-phenylene sulfide) and the like can be exemplified.

The metal salt may include, for example, lithium salt, lithium imide, lithium amide, potassium salt, and the like, and the ionic liquid may be pyridine imide. Etc. can be mentioned. The carbon material may include carbon black, graphite, graphene, graphene, carbon nanotubes (CNT), carbon nanofibers (CNF), and the like. One or more selected may be exemplified, and the surfactant may include sulfonate, quaternary ammonium salt, lauryl dimethylbenzyl ammonium salt, and the like.

The antistatic layer 20 may include a conductive polymer as described above, a metal salt, an ionic liquid, a carbon material and a surfactant, and the like, and preferably, among the antistatic agents listed above, polyethylene dioxythiophene (PEDOT). ) May be included. Specifically, as the antistatic agent, polyethylene dioxythiophene (PEDOT) alone may be used, or polyethylene dioxythiophene (PEDOT) may be used by mixing one or more of those listed above. Since the polyethylene dioxythiophene (PEDOT) has a high visible light transmittance and uses polystyrenesulfonate as a dopant during the polymerization, the polyethylene dioxythiophene (PEDOT) has excellent coating stability compared to other conductive polymers when coated on the base film 10, and a binder. It is useful in the present invention because of excellent mixing properties with the resin and high antistatic performance.

The antistatic layer 20 is formed by coating an antistatic composition comprising the binder resin and the antistatic agent as described above, according to a preferred embodiment of the present invention 1 to 30% by weight of the antistatic agent and the binder based on the total weight of the antistatic composition It is preferable that the antistatic composition comprising 5 to 25% by weight of the resin is coated and formed. In this case, when the content of the antistatic agent is less than 1% by weight, the antistatic performance according to its content is insignificant, and when the content of the antistatic agent exceeds 30% by weight, the content of the binder resin may be relatively low, and thus interlayer adhesion may be undesirable. And when the content of the binder resin is less than 5% by weight is too low, the adhesive strength is weak, the interlayer adhesion with the base film 10, etc. is lowered, and if the content is more than 25% by weight, the content of the antistatic agent is relatively low, good antistatic It is difficult to plan performance. In consideration of this point, it is more preferable that the antistatic composition contains 5 to 25% by weight of an antistatic agent and 10 to 20% by weight of the binder resin.

In addition, the antistatic composition may further include a solvent for coating property, the solvent may be selected from alcohol, water and the like. The alcohol may be selected from, for example, methyl alcohol, ethyl alcohol, propyl alcohol and the like. The antistatic composition may contain, for example, 5 to 30% by weight of alcohol and 10 to 50% by weight of water, based on the total weight of the composition. In this case, when the content of the alcohol and water as the solvent is less than the above range may be poor coating property, when the content of the solvent is more than the above range may be relatively low content of the antistatic agent and the binder resin may have a low antistatic performance and / or interlayer adhesion. In addition, the antistatic composition may further include additives such as antioxidants, fillers, leveling agents and dispersants for uniform dispersion of each component in 0.01 to 1.0% by weight.

The antistatic layer 20 is formed by coating the antistatic composition as described above, for example, gravure coating (Micro Gravure) coating, Micro Gravure coating, Keith Gravure coating, Comma Knife (Comma Knife) coating It may be formed by coating through one method selected from a roll coating, a spray coating, a Meyer bar coating, a slot die coating, and a reverse coating method. It is not limited by.

At this time, the antistatic layer 20 has a suitable thickness of 10nm to 1,000nm in accordance with the present invention. By such a thickness, it is possible to have excellent antistatic performance and adhesion. At this time, when the thickness of the antistatic layer 20 is less than 10nm, it is difficult to exhibit excellent antistatic performance. In addition, when the thickness of the antistatic layer 20 exceeds 1,000 nm, the curing property may be insufficient, or the adhesion between the base film 10 may be weak, and interlayer peeling may occur. In consideration of this point, the antistatic layer 20 preferably has a thickness of 50nm to 300nm. When the thickness of the antistatic layer 20 is in a preferred range of 50 nm to 300 nm, it has very excellent characteristics in antistatic performance and adhesion.

In addition, the antistatic layer 20, by controlling the content and thickness of the antistatic agent, the surface resistance of the antistatic layer 20 is preferably 10 ¹⁰ Ω / □ or less. In this case, good surface resistance of the adhesive layer 30 is realized, and has excellent peeling charging characteristics. Preferably, the antistatic layer 20 has a surface resistance of 10 ⁷ GPa / □ or less, more preferably 10 ⁴ to 10 ⁶ GPa / □. When it has such a preferable range, it has an ideal characteristic in the surface resistance and peeling charge of the adhesion layer 30.

On the other hand, the adhesive layer 30 is not limited as long as it has a good adhesive force with the adherend. The pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer 30 includes at least one pressure-sensitive adhesive selected from the pressure-sensitive resin, and may further include a curing agent. The pressure-sensitive adhesive may be used that is commonly used in the art, it may be selected from thermosetting and ultraviolet curing. In addition, the curing agent may be used at least one selected from isocyanate-based and epoxy-based.

The pressure-sensitive adhesive layer 30 preferably contains at least one pressure-sensitive adhesive selected from acryl-based and urethane-based polymers as a main component, and more preferably includes an acrylic pressure-sensitive adhesive. In this case, the acrylic pressure-sensitive adhesive has a crosslinkable functional group, which may be selected from, for example, having one or more functional groups selected from a hydroxy group (OH-) and a carboxyl group (COOH-).

According to a preferred embodiment, the acrylic pressure-sensitive adhesive preferably has a hydroxyl group alone. Thus, in using an acrylic adhesive, when using what has a hydroxyl group alone, it is very advantageous in surface resistance and peeling charging characteristic.

In addition, it is preferable to use an isocyanate curing agent for the curing agent. The isocyanate-based curing agent is not limited as long as it has an isocyanate group (NCO-) in the molecule, for example, 4,4-dicyclohexylmethane diisocyanate, isophorone diisocyanate, 2,4,6-triisopropylphenyl One or more selected from diisocyanate, 4,4-diphenylmethane diisocyanate, tolidine diisocyanate, naphthalene diisocyanate and the like can be used.

In addition, the adhesive layer 30 preferably has an adhesive force of 3gf / 25mm ~ 50gf / 25mm. In this case, when the adhesive force of the adhesive layer 30 is less than 3gf / 25mm, the adhesion force with the adherend is insignificant, and when the adhesive force of the adhesive layer 30 exceeds 50gf / 25mm, peeling may be difficult when removing from the adherend. In view of this, it is more preferable that the adhesive layer 30 has an adhesive force of 12 gf / 25 mm to 30 gf / 25 mm.

At this time, the adhesive layer 30 is an isocyanate-based curing agent 2 having a solid content of 20 to 75% by weight with respect to 100 parts by weight of the acrylic pressure-sensitive adhesive having a hydroxyl group to have a good adhesive force, that is, 3gf / 25mm ~ 50gf / 25mm adhesive strength 2 It is preferable that the pressure-sensitive adhesive composition containing 5 parts by weight is coated.

In addition, the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 30 may further include a silane coupling agent in addition to the pressure-sensitive adhesive and the curing agent. As said silane coupling agent, the silane coupling agent which has an epoxy group is preferable. The epoxy group of the silane coupling agent is combined with the reactive group of the acrylic pressure-sensitive adhesive, improves the adhesion stability, and prevents a decrease in the adhesive force when left for a long time under high temperature and high humidity conditions.

In addition, the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 30 is a solvent (organic solvent) for coating properties; And as for a specific purpose, it may further include, for example, plasticizers, epoxy resins, photoinitiators, ultraviolet stabilizers, antioxidants, fillers and the like, which may be selected from those commonly used in the art.

In addition, the application of the pressure-sensitive adhesive layer 30, that is, the application of the pressure-sensitive adhesive composition may be applied on the antistatic layer 20 by a coating method generally used in the art, but is not particularly limited, for example, die coater , Nip coaters, gravure roll coaters and comma coaters can be used. And after application, for example, it can be dried at 50 ~ 110 ℃.

At this time, the adhesive layer 30 has a suitable thickness of 5㎛ ~ 30㎛ according to the present invention. By such a thickness, it is possible to prevent the transition phenomenon while having excellent antistatic performance. And it can have excellent wetting properties. Specifically, when the thickness of the adhesive layer 30 is less than 5 μm, the wettability is poor and it is difficult to adhere to the adherend with good adhesive force. That is, the adhesion to the adherend is weak due to the low wettability, and interlayer separation may occur. In addition, when the thickness of the adhesive layer 30 exceeds 30 μm, surface resistance and peeling charging characteristics may be deteriorated, and a transition phenomenon may occur in which the adhesive is transferred during peeling removal from the adherend. In consideration of this point, it is preferable that the adhesive layer 30 has a thickness of 15 μm to 25 μm. According to the present invention, when the adhesive layer 30 has a thickness of 15 μm to 25 μm as a preferred range, it has excellent antistatic performance and has very ideal properties in transition phenomenon and wettability.

In addition, the surface resistance of the adhesive layer 30 may have a thickness of 10 ¹² Ω / □ or less by adjusting the thickness of the adhesive layer 30 and the thickness of the antistatic layer 20, but preferably 10 ¹⁰ Ω / □ Hereinafter, according to a more preferred embodiment it is preferable to have a surface resistance of 10 ⁶ ~ 10 ⁸ Ω / □. In addition, the adhesive layer 30 preferably has a peeling charge of 3.0 kV or less. The adhesive layer 30 more preferably has a peeling charge of 1.0 kV or less, specifically, a peeling charge of 0.01 to 1.0 kV. In the case of having the surface resistance and the peeling charging characteristic of this preferred range, the antistatic performance when peeling from the adherend is very excellent. In the present invention, the peeling charge refers to the amount of static electricity (voltage) generated on the surface of the adherend during peeling after the adhesive protective film is laminated on the adherend.

On the other hand, the release film 40, when the protective film is attached to the adherend as described above, which is peeled off, and includes a release substrate 42, and a release layer 44 formed on the release substrate 42. . This release film 40 may be configured as usual.

For example, the release substrate 42 may be selected from paper, nonwoven fabric and plastic film. According to a specific embodiment, the release substrate 42 is a plastic film, for example, may be a film including a polyester-based and / or polyolefin-based. The release base material 42 is, for example, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), polyethylene (PE) and polypropylene (for example). Films comprising one or more resins selected from the group consisting of PP) and the like may be used, but are not limited thereto.

In addition, the release layer 44 may have release characteristics such as the adhesive layer 30 and good release force (peeling force). The release layer 44 may be composed of, for example, a silicone layer coated with a silicone composition. As the release layer 44, the silicon layer may include, for example, a compound having a Si—H bond in the molecule and a silicon polymer of polysiloxane. As the silicone polymer, for example, 3705 ^® (manufactured by Shin-Yestsu) or 7226 ^® (manufactured by Dow Corning) may be used as a commercial product. For example, the release layer 44 may be coated with a silicone composition including a silicone polymer such as dimethylpolysiloxane and organopolysiloxane, a curing agent such as organohydrogen polysiloxane, a catalyst such as platinum chelate, and a solvent. But is not limited thereto.

According to the present invention described above, there is no transition phenomenon such as an antistatic agent and an adhesive, and has excellent antistatic properties and physical properties.

Specifically, the antistatic layer 20 is formed between the base film 10 and the adhesive layer 30, there is no surface elution of the antistatic agent. And the base film 10 is corona-treated or the primer layer 12 is formed in the surface in which the antistatic layer 20 was formed, and has the outstanding interlayer adhesion with the antistatic layer 20. In addition, since the antistatic layer 20 has a thickness of 10 nm to 1,000 nm, it has an excellent antistatic property such as surface resistance and peeling charge (voltage at the surface of the adherend when peeling), together with securing interlayer adhesion. In addition, the pressure-sensitive adhesive layer 30 has a thickness of 5 μm to 30 μm, and has excellent surface resistance, peeling charge, and the like, no transition phenomenon, and excellent wettability.

According to a preferred embodiment of the present invention, the primer layer 12 is formed by coating an acrylic resin or polyester resin, the antistatic layer comprises polyethylene dioxythiophene (PEDOT) as an antistatic agent, 50nm ~ 300nm When the adhesive layer 30 includes an acrylic pressure-sensitive adhesive having a hydroxyl group, but has a thickness of 15 ㎛ to 25 ㎛, the adhesion between the base film 10 and the antistatic layer 20, antistatic It has very ideal characteristics in characteristics (surface resistance and peeling charging characteristics), adhesion to the adherend, transition phenomenon and wettability.

The adhesive protective film according to the present invention can be usefully used for surface protection in general industrial products as well as electronic components, semiconductor components, and the like, and its application field is not limited. More specifically, for example, a display panel such as a liquid crystal display panel (PDP) or a plasma display panel (PDP) constituting a display device such as a mobile phone, a computer monitor, a TV, and various advertisement boards as described above. ; Optical elements such as polarizing plates; And it can be usefully used for various semiconductors, wiring boards and the like.

Hereinafter, examples and comparative examples of the present invention will be exemplified. The following examples are provided to illustrate the present invention in order to facilitate understanding of the present invention, and thus the technical scope of the present invention is not limited thereto.

[ Example 1 and Comparative Example 1] -Evaluation of the physical properties according to the configuration of the antistatic layer

A 50 μm-thick PET (polyethylene terephthalate) film was prepared, and one surface thereof was subjected to corona discharge treatment. And the antistatic composition was coated on the corona treated surface of the PET film to form an antistatic layer. The antistatic layer was formed by coating an antistatic composition including 10 wt% of an antistatic agent, 15 wt% of an acrylic resin as a binder resin, 30 wt% of an alcohol (ethyl alcohol), and 45 wt% of water. At this time, as shown in Table 1 below, the thickness (nm) of the antistatic layer and the type of the antistatic agent were different according to the Examples and Comparative Examples. The antistatic agent was selected from polyethylene dioxythiophene (PEDOT), pyridine imide, potassium salt, potassium ion and polyaniline.

Evaluation of the surface resistance, transparency and adhesion for the specimens (PET / anti-static layer laminated structure) according to each Example and Comparative Example prepared as described above, the results are shown in the following [Table 1]. In this case, the surface resistance was measured for the antistatic layer at a constant temperature and humidity conditions of 22 ℃, 55% RH by using a surface resistance meter (Model No.-19781) of Disco (Desco), the transparency is usually It was measured using the transparency meter used. And the adhesion is the adhesion between the PET film and the antistatic layer, which evaluated the peeling degree of the antistatic layer by the cross-out (Cross-Out) measuring method. At this time, according to the degree of peeling, very good (◎), excellent (○), normal (△), bad (X) is shown in the following [Table 1].

<Results of the evaluation of physical properties according to the composition of the antistatic layer> Item Example
1-1 Example
1-2 Example
1-3 Example
1-4 Example
1-5 Example
1-6 Comparative Example
1-1 Comparative Example
1-2 Of PET film
Thickness (㎛) 50 50 50 50 50 50 50 50 Antistatic layer
Thickness (nm) 100 200 300 400 100 100 8 1,100 Antistatic
Kinds PEDOT PEDOT Pyridine imide Potassium salt Lithium ion Polyaniline PEDOT PEDOT Surface resistance
(Ω / □) 3x10 ⁵ 1 x 10 ⁵ 4 x 10 ⁶ 3 x 10 ⁶ 2x10 ⁵ 1 x 10 ⁵ 6 x ^{10 8} 1 x 10 ⁵ transparency
(Haze,%) 1.8 2.2 1.9 4.8 2.5 1.9 2.0 1.8 Adhesion
○ ○ ○ △ ○ △ ◎ X

As shown in [Table 1], it was found that the surface resistance and adhesion were changed according to the thickness of the antistatic layer. In this case, according to the present invention, in the case of having an appropriate thickness range (10 nm to 1,000 nm), that is, in the range of 100 nm to 400 nm, it was found that the surface resistance and adhesion were superior at the same time than the comparative examples. . And it had a more favorable characteristic in the range of 100 nm-300 nm in thickness. In addition, it was found that polyethylene dioxythiophene (PEDOT) had superior properties in surface resistance than other materials in the type of antistatic agent.

[ Example 2 and Comparative Example 2] -Evaluation of the physical properties according to the surface treatment of the base film

An antistatic layer was formed on one surface of a 50 μm-thick PET (polyethylene terephthalate) film. At this time, the antistatic layer was formed in the same manner, the surface treatment of the PET film was different according to each Example and Comparative Example. Specifically, the antistatic layer comprises an antistatic composition comprising 10 wt% polyethylene dioxythiophene (PEDOT) as an antistatic agent, 15 wt% acrylic resin as a binder resin, 30 wt% alcohol (ethyl alcohol) and 45 wt% water. The coatings were all made equal at a thickness of 100 nm. And in the case of PET film, as shown in the following [Table 2], the surface treatment was different as the corona treatment, acrylic primer coating, urethane primer coating and polyester primer coating according to each Example and Comparative Example.

Adhesion was evaluated on the specimens (PET / antistatic layer laminated structure) according to each of the examples and comparative examples prepared as described above, and the results are shown in the following [Table 2]. Adhesion is adhesion between the PET film and the antistatic layer, and the measuring method is as described above.

<Evaluation of Physical Properties According to Surface Treatment of Substrate Films> Item Example
2-1 Example
2-2 Example
2-3 Example
2-4 Comparative Example
2-1 Of PET film
Thickness (㎛) 50 50 50 50 50 Of PET film
Surface treatment corona
process acryl
primer urethane
primer Polyester
primer Not processed
Not Antistatic layer
Thickness (nm) 100 100 100 100 100 Antistatic
Kinds PEDOT PEDOT PEDOT PEDOT PEDOT Adhesion
○ ◎ ○ ◎ △

As shown in [Table 2], when the PET film according to the embodiment of the present invention it can be seen that the adhesion is improved compared to the non-treated comparative example. In particular, in performing the surface treatment, it was found that the acrylic primer coating (Example 2-2) or polyester primer coating (Example 2-4) has a very good adhesion.

[ Example 3 and Comparative Example 3] -Evaluation of the physical properties according to the configuration of the adhesive layer

A 50 μm-thick PET (polyethylene terephthalate) film was prepared, and one surface thereof was coated with an acrylic primer. And an antistatic layer was formed on the surface coated with the acrylic primer of the PET film. Next, an adhesive layer was formed on the antistatic layer to have a laminated structure of PET / acrylic primer layer / antistatic layer / adhesive layer, but the adhesive layer was changed according to each example and comparative example.

Specifically, the antistatic layer comprises an antistatic composition comprising 10 wt% polyethylene dioxythiophene (PEDOT) as an antistatic agent, 15 wt% acrylic resin as a binder resin, 30 wt% alcohol (ethyl alcohol) and 45 wt% water. The coatings were all made equal at a thickness of 100 nm.

As shown in Table 3 below, the thickness (μm) of the pressure-sensitive adhesive layer and the type of the pressure-sensitive adhesive were varied according to the Examples and Comparative Examples. At this time, the pressure-sensitive adhesive layer is formed by coating a pressure-sensitive adhesive composition comprising 3 parts by weight of an isocyanate-based curing agent having a solid content of 42% by weight and 250 parts by weight of a solvent (methyl ethyl ketone) with respect to 100 parts by weight of the acrylic pressure-sensitive adhesive, but each Example and Comparative According to the example, acrylic adhesives having different functional groups were used, and the thickness (μm) of the adhesive layer was also changed.

In addition, in the case of Comparative Example 3-3, an antistatic layer was formed on the outer surface of the PET film, that is, on the opposite side to the surface on which the adhesive layer was formed to have a laminated structure of an antistatic layer / PET / adhesive layer. In the case of Comparative Example 3-4, an antistatic agent (PEDOT) was mixed with the adhesive layer to give a laminate structure of PET / adhesive layer (antistatic agent mixed).

With respect to the adhesive protective film specimens according to each of the examples and comparative examples prepared as described above, the adhesive strength, surface resistance, peeling charge, transparency, adhesion, transition phenomenon and wetting (wetting) characteristics were evaluated by the following method, and the result Is shown in the following [Table 3]. At this time, the method of measuring the transparency and adhesion is as described above.

<Adhesion>

Adhesion was measured by using a tensile strength tester at each peeling angle of 180 degrees after pressing the adhesive protective film specimen to the metal plate (aluminum).

Surface Resistance

Surface resistance was measured with respect to the surface of the adhesion layer in the constant temperature and humidity conditions of 22 degreeC and 55% RH using the high ohmmeter (model number MCT-HT450) of Mitsubishi Corporation, Japan.

<Seoul Destroyed War>

Peeling charge was evaluated for each adhesive protective film specimen as follows.

1) 100 mm x 70 mm (horizontal x vertical) sized substrate (organic substrate) preparation

2) Cut the adhesive protective film to the same size as above

3) Laminating the pressure-sensitive adhesive film and the adherend with a pressure of 2kgf using a paper

4) After the laminated sample is fixed on an acrylic plate, it is allowed to stand for 30 minutes under normal temperature and humidity conditions (24 ℃, 60% RH).

5) Place the detection part of the peeling voltage measuring instrument (model number KSD-0103, Japan) at a distance of 10 cm from the adhesive protective film and the adherend.

6) Peel off the adhesive protective film from the adherend at a speed of about 30m / min

7) Measuring peeling voltage (kV) on the surface of the adherend during peeling of the adhesive protective film

<Transition Phenomena>

In the transition phenomenon, the adhesive protective film specimen was attached to a glass substrate, and then left to stand at high temperature and high humidity conditions (60 ° C., 90% RH). And after removing the adhesive protective film specimen, the staining of the glass substrate and the pressure-sensitive adhesive transition phenomenon was observed, as shown in the following [Table 3].

◎: no transition, ○ ○: fine stains,

△: Normal, X: Smeared or adhesive transition

Wetting characteristics

The wettability characteristics of the adhesive protective film specimens were directed toward the glass substrate, but when placed on the glass substrate, it was evaluated how quickly the adhesive layer adhered to the surface of the glass substrate. At this time, when the adhesion layer was measured to be in close contact with the entire surface of the glass substrate and was very fast within 2 seconds, it was "excellent" as excellent. When it is 2 seconds or more and less than 10 seconds, it is excellent as "(circle)";"Δ" usually for 10 seconds or more; And when the pressure-sensitive adhesive layer is in close contact with only a part of the glass substrate, as the wettability is poor as divided by "X", the results are shown in the following [Table 3].

<Results of Physical Property Evaluation According to the Composition of the Adhesive Layer> Item Example
3-1 Example
3-2 Example
3-3 Comparative Example
3-1 Comparative Example
3-2 Comparative Example
3-3 Comparative Example
3-4 Of PET film
Thickness (㎛) 50 50 50 50 50 50 50 Of PET film
Surface treatment acryl
primer acryl
primer acryl
primer acryl
primer acryl
primer - - Antistatic layer
Thickness (nm) 100 100 100 100 100 100
(PET exterior) - Antistatic
Kinds PEDOT PEDOT PEDOT PEDOT PEDOT PEDOT PEDOT Adhesive layer
Thickness (㎛) 15 25 20 3 35 10 20
Antistatic Agent Adhesive
Kinds OH
Functional group COOH
Functional group OH + COOH
Functional group OH
Functional group OH
Functional group OH
Functional group OH
Functional group adhesiveness
(gf / 25 mm) 20 30 25 8 24 10 10 Surface resistance
(Ω / □) 1 x 10 ⁷ 5 x 10 ⁸ 8 x 10 ⁷ 8 x 10 ⁶ 2 x 10 ⁸ Not measurable 3 x ^{10 11} Peeling charge
(kV) 0.2 0.6 0.4 0.1 1.2 6.9 0.1 transparency
(Haze,%) 1.9 2.0 1.8 1.8 2.1 1.8 1.9 Adhesion
◎ ◎ ◎ ◎ ◎ - - Transition phenomenon
◎ ○ ○ ◎ △ ◎ X Wet
(Wetting) ◎ ◎ ◎ X ◎ △ △

As shown in Table 3, it can be seen that the properties vary depending on the thickness of the pressure-sensitive adhesive layer and the type of pressure-sensitive adhesive. At this time, when the adhesive layer according to the present invention has an appropriate thickness range (5㎛ ~ 30㎛), that is, in the case of embodiments in the range of 15㎛ ~ 25㎛, surface resistance, peeling charge, transition phenomenon than the comparative examples And it was found to be excellent in all physical properties such as wetting properties. And it can be seen that the pressure-sensitive adhesive has a hydroxyl group (OH-) is advantageous to the physical properties. In addition, when the antistatic agent is coated on the outer surface of the base film (PET film) (Comparative Example 3-3) or mixed into the adhesive layer (Comparative Example 3-4), the surface resistance and peeling charge are not good. The transition of and the wetting (Wetting) was found to be inferior.

As can be seen from the above examples, it can be seen that the substrate film (PET film) according to the present invention is advantageous in improving the adhesion when the surface-treated one, in particular, acrylic resin or polyester resin is coated. In addition, when the antistatic layer and the adhesive layer have an appropriate thickness, it can be seen that it has excellent properties in various physical properties such as antistatic performance, transition phenomenon and wettability as well as securing adhesion. In addition, it can be seen that it is preferable that the antistatic agent uses polyethylene dioxythiophene (PEDOT), and that the pressure sensitive adhesive has a hydroxyl group among the acrylic type.

10: base film 12: primer layer
20: antistatic layer 30: adhesive layer
40: release film 42: release substrate
44: release layer

Claims (10)

A base film;
An antistatic layer formed on the base film; And
Including an adhesive layer formed on the antistatic layer,
The base film is corona treated or a primer layer is formed on the surface on which the antistatic layer is formed,
The antistatic layer has a thickness of 100nm to 300nm,
The adhesive layer has a thickness of 15 μm to 25 μm,
The primer layer includes an acrylic resin or a polyester resin, the antistatic layer uses polyethylene dioxythiophene (PEDOT) as an antistatic agent, and the adhesive layer uses an acrylic pressure sensitive adhesive having a hydroxyl group as the pressure sensitive adhesive,
The antistatic layer is formed by coating an antistatic composition comprising 1 to 30% by weight of the antistatic agent and 5 to 25% by weight of the binder resin, based on the total weight of the composition,
The pressure-sensitive adhesive layer is formed by coating an adhesive composition including 2 to 5 parts by weight of an isocyanate-based curing agent having a solid content of 20 to 75% by weight with respect to 100 parts by weight of an acrylic pressure-sensitive adhesive having a hydroxyl group,
The adhesive layer has a surface resistance of 10 ⁶ ~ 10 ⁷ Ω / □, peeling charge of 0.01 ~ 0.2 kV, the adhesive strength of 3gf / 25mm ~ 50gf / 25㎜ adhesive protection film. delete delete delete delete delete delete delete delete delete

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