KR101951660B1 - Adhesive film including inorganic particles for removing optical clear adhesives, method for preparing the same - Google Patents

Abstract

The present invention relates to an adhesive film for removing optically clear adhesive (OCA) including silicon fine particles, and a manufacturing method thereof, which are for a removing process of the OCA of a display or a touch screen. The present invention includes an adhesive layer formed between a first substrate and a second substrate, wherein the adhesive layer includes silicon fine particles as an additive based on acrylate based resin. By the above, the present invention is not disconnected even when used in a middle or large-sized display by having more excellent tensile strength and elongation than using an inorganic filler or liquid rubber as an existing additive, is able to prevent a display from being damaged even when used in a small display by securing stable peeling force, and can effectively remove OCA.

Description

TECHNICAL FIELD [0001] The present invention relates to an adhesive film for removing an optical transparent adhesive containing silicon fine particles, and a process for producing the adhesive film. [0002] The present invention relates to a pressure-

The present invention relates to an adhesive film used for removing an optically clear adhesive (OCA) of a touch screen or a display, and has excellent tensile strength, elongation, and stable peeling force, Which is capable of effectively removing an optical transparent adhesive without using an optical transparent adhesive.

As the mobile phone touchscreen market grows, interest in adhesive materials used between mobile phone window glass and touchscreen panel sensor glasses is increasing. In a typical touch screen structure, a touch screen panel (TSP) is attached to a film layer formed with a sensing electrode and a cover lens through an OCA (optically clear adhesive) transparent adhesive layer through a lamination process or the like.

However, various kinds of adhesion failures such as bubbles, foreign matters, defective bonding position, etc. occur during the cementation process. The industry estimates that there are more than 20% of loosely welded joints, although the figures vary somewhat depending on the product.

Accordingly, touch screen panel manufacturers are interested in playing expensive front windows (eg, tempered glass), ITO, and FPCB components.

Although the bonding method is somewhat different depending on the product, the optical transparent adhesive for bonding the front window and the ITO pattern film has a very strong adhesive property, so that it is very difficult to separate after the adhesion, It is very difficult to remove the transparent adhesive.

In this regard, the inventors of the present invention have proposed an adhesive film for removing an optical transparent adhesive including an inorganic filler, a method for producing the adhesive film, a method for removing an optical transparent adhesive of a touch screen using the adhesive film, The present invention provides an adhesive film which is attached to an optical transparent adhesive (OCA) through an adhesive layer and removes OCA from an adherend through an adhesive layer formed between the first and second base materials, (OCA) removal adhesive film comprising a pressure-sensitive adhesive composition comprising an acrylate base resin, a polyfunctional crosslinking agent, a silane coupling agent, a photopolymerization initiator, an additive and an inorganic filler. The adhesive film contains an inorganic filler as an additive. Thus, an adhesive film excellent in tensile strength can be produced.

However, since the inorganic filler has a high specific gravity, it has a disadvantage in that the uniformity of the film is lowered due to the precipitation phenomenon when the time elapses after the synthesis, and when the content exceeds a certain level, the tensile strength is increased but the elongation and peeling force are decreased .

Accordingly, there is always a need to develop a pressure-sensitive adhesive film capable of effectively removing the optical transparent adhesive without breaking the display due to a stable peeling force without breaking due to excellent tensile strength and elongation.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide an adhesive film capable of effectively removing an optical transparent adhesive without breakage of the display with a stable peeling force without breaking with an excellent tensile strength and elongation to be.

One embodiment of the present invention relates to an adhesive film which is attached to an optical transparent adhesive (OCA) and removes the optical transparent adhesive from an adherend, the adhesive film comprising: a first substrate; A second substrate facing the first substrate; And a pressure-sensitive adhesive layer formed between the first substrate and the second substrate, wherein the pressure-sensitive adhesive layer is composed of a pressure-sensitive adhesive composition comprising an acrylate base resin and silicon fine particles, (OCA) is contained in an amount of 0.5 to 20 parts by weight in terms of silicon fine particles having a size within a range of 0.5 to 20 占 퐉 based on 100 parts by weight of the resin.

Further, the silicon fine particles may have a size within a range of 1.0 탆 to 10 탆.

The silicon fine particles may be included in the range of 3.0 to 20 parts by weight.

The silicon fine particles may have a size ranging from 3.0 μm to 5.0 μm and may be included in the range of 4.0 to 20.0 parts by weight.

The adherend is a small adherend having an area within a range of 50 cm < 2 > to 500 cm < 2 >, and the silicon fine particles have a size ranging from 3.0 mu m to 5.0 mu m and can be included in a range of 4.0 to 7.0 wt.

Also, the adherend is a medium or large-sized adherend having an area within a range of 500 cm 2 to 10,000 cm 2, and the silicon fine particles have a size ranging from 3.0 μm to 5.0 μm and may be included within a range of 15-20 parts by weight.

Here, the silicon fine particles may be surface-treated silicon fine particles obtained by drying for 1 hour to 5 hours at a temperature of 100 ° C to 150 ° C to remove moisture or contaminants from the surface.

The acrylate base resin may include ethylhexyl acrylate (EHA), 2-hydroxyethyl acrylate (HEA), isobornyl acrylate (IBOA), and acrylic acid (AA) .

The acrylate base resin may further contain 40 to 90 parts by weight of ethylhexyl acrylate (EHA), 10 to 30 parts by weight of 2-hydroxyethyl acrylate (HEA), 15 to 30 parts by weight of isobornyl acrylate (IBOA) , And 5 to 25 parts by weight of an acrylic acid (AA).

The pressure-sensitive adhesive composition may further comprise a multifunctional crosslinking agent, a silane-based coupling agent, a photopolymerization initiator, and a molecular weight modifier.

The pressure-sensitive adhesive composition may further comprise 0.005 to 10 parts by weight of a multifunctional crosslinking agent, 0.01 to 3 parts by weight of a silane coupling agent, 0.01 to 10 parts by weight of a photopolymerization initiator, and 0.01 to 1 part by weight of a molecular weight modifier based on 100 parts by weight of the acrylate base resin. Parts by weight.

The details of other embodiments are included in the detailed description and drawings.

The present invention is characterized in that it comprises an adhesive layer formed between a first substrate and a second substrate, wherein the adhesive layer is based on an acrylate base resin and comprises silicon fine particles as an additive, It is possible to have a remarkably excellent tensile strength and elongation rate as compared with the case using an inorganic filler or a liquid rubber so that a stable peeling force can be ensured without being broken even if it is used in a medium to large size display and the display is not damaged even if used for a small display, The optical transparent adhesive can be removed.

1 is a schematic view showing an adhesive film for removing an optical transparent adhesive (OCA) containing silicon fine particles according to an embodiment of the present invention.
2 is a flowchart showing a method for producing an adhesive film for removing an optical transparent adhesive (OCA) containing silicon fine particles according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and will be described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

Throughout this specification, when a section is referred to as " including " an element, it is understood that it does not exclude other elements, but may include other elements, The terms " about ", " substantially ", and the like used to the extent that they are used in the context of the present invention are used in their numerical values or in close proximity to their numerical values when the manufacturing and material tolerances inherent in the meanings mentioned are presented, Or absolute numbers are used to prevent unauthorized exploitation by unauthorized intruders of the mentioned disclosure. The term " step " or " step of ~ " as used throughout the specification does not imply "

1 is a schematic view showing an adhesive film for removing an optical transparent adhesive (OCA) containing silicon fine particles according to an embodiment of the present invention.

As shown therein, the present invention is an adhesive film attached to an optical transparent adhesive (OCA) to remove the optical transparent adhesive from an adherend, the adhesive film comprising: a first substrate 100; A second substrate (300) disposed opposite the first substrate; And an adhesive layer (200) formed between the first substrate and the second substrate.

The adhesive film according to the present invention is an adhesive film for removing an optical transparent adhesive which can be used for removing an optically clear adhesive (OCA) attached to a touch screen or a display. For example, in the touch screen reproduction process for reusing element parts in a smart phone, an automobile electric field, or a small, medium, and large display module, an adhesive film for removing OCA that can be used in the process of removing optical transparent adhesive (OCA) to be.

The first base material 100 and / or the second base material 300 are for storing, distributing or distributing the adhesive layer 200, and are not particularly limited and may be a release paper well known in the art. When the adhesive film according to the present invention is used, the first base material 100 and / or the second base material 300 are removed, and the adhesive layer 200 is adhered to the optical transparent adhesive (OCA) The optical transparent adhesive (OCA) can be removed from the adherend by removing it. In the present invention, a polyethylene terephthalate (PET) release film is used as the first base material 100 and / or the second base material 300.

In the present invention, the adhesive layer 200 is formed of a pressure-sensitive adhesive composition comprising an acrylate base resin and silicon fine particles.

In general, an acrylate base resin or an acrylic monomer has adhesiveness to itself and can be easily produced at normal temperature and pressure, and thus is widely used in an adhesive layer or an adhesive. However, acrylic monomers alone have limitations in increasing tensile strength and elongation. Therefore, it is desirable to add an additive having a high elastic modulus to improve the tensile strength and elongation to overcome such disadvantages.

The present inventors have previously produced an adhesive film excellent in tensile strength and elongation by using an inorganic filler as an additive based on an acrylate base resin. However, since the inorganic filler has a high specific gravity, it has a disadvantage in that the uniformity of the film is lowered due to the precipitation phenomenon when the time elapses after the synthesis, and when the content exceeds a certain level, the tensile strength is increased but the elongation and peeling force are decreased .

Accordingly, the inventors of the present invention have conducted research for a long time in order to produce an adhesive film having excellent tensile strength and elongation at the same time and having a stable peeling force. As a result, when silicon fine particles are used as an additive, The present inventors completed the present invention after confirming that the optical transparent adhesive can be effectively removed without breakage of the display due to its stable peel force without breaking the adhesive layer with excellent tensile strength and elongation.

The inorganic filler used as an additive in the prior art has a high specific gravity, which causes a disadvantage that precipitation occurs when time passes after synthesis. When the precipitation phenomenon occurs, the uniformity of the film is lowered, but when the silicon fine particles are used, the precipitation phenomenon does not occur. In addition, when the content of the inorganic filler exceeds a certain amount, the tensile strength is increased while the elongation and peeling force are decreased. On the other hand, when the silicone fine particles of the present invention are used, the tensile strength and elongation are increased and the peeling force is not significantly decreased (See Experimental Examples 1 to 3 of the present invention).

Further, when a liquid rubber is used as an additive, when it is used in excess of a certain amount, the viscosity and peeling force are increased and the use thereof is limited. However, there is no such limitation with the use of silicon fine particles. Silicone fine particles had no significant effect on the viscosity change compared to liquid rubber, so there was no limitation (not great) in the amount of use, and it was effective in increasing the tensile strength and elongation which are the physical characteristics of the OCA removing adhesive film. In addition, the peeling force was not significantly changed as compared with the liquid rubber, and there was little fear of damaging the display module and the element parts (see Experimental Examples 1 to 3 of the present invention).

In addition, when an inorganic filler or a liquid rubber is used as an additive, there is a disadvantage that the adhesive film is broken or the display is broken, so that it can be used only for a small display. However, if silicon fine particles are used as an additive according to the present invention, It is possible to have a significantly higher tensile strength and elongation than an inorganic filler or a liquid rubber, so that even when used in a medium to large-sized display, a stable peeling force can be ensured without being broken, The transparent adhesive can be removed.

Also, in the present invention, the silicon fine particles are characterized by containing silicon fine particles having a size within a range of 0.5 μm to 20 μm with respect to 100 parts by weight of the acrylate base resin within a range of 0.5 to 20 parts by weight.

Generally, the modulus of elasticity of acrylic is 30 kg / cm 2, and the modulus of elasticity of the silicone particles is 108 kg / cm 2. In the present invention, silicon fine particles having an elastic modulus about three times higher than that of acrylic are further included as additives, The tensile strength and elongation of the pressure-sensitive adhesive film can be increased by improving the elasticity so as to escape the limit of the monomer.

Further, the present inventors conducted experiments to find optimization conditions for increasing tensile strength, elongation and peeling force based on the particle size, content control, and surface treatment of silicon fine particles based on acrylic base resin. That is, in order to confirm and compare the physical properties of the OCA removing film including the silicon fine particles according to one embodiment of the present invention, the particle content (0.5 to 20 parts by weight) of the silicon fine particles and the particle size (0.5 to 1 占 퐉, 1 to 3 탆, 3 to 5 탆, 5 to 10 탆, 10 to 15 탆, and 15 to 20 탆), and the tensile strength, elongation, peeling strength, OCA removal rate was measured.

As a result, it is preferable that the silicon microparticles have a size within the range of 0.5 to 20 mu m. When the particle size of the silicon fine particles was out of the above range, the tensile strength and the elongation were lowered, and the OCA removal rate was also lowered (see Example 11 and Example 1 of the present invention). According to this, the silicon fine particles preferably have a size in the range of 0.5 to 20 mu m, more preferably in the range of 1.0 to 10 mu m, and most preferably in the range of 3.0 to 5.0 mu m.

The silicon fine particles may be contained in an amount of 0.5 to 20 parts by weight based on 100 parts by weight of the acrylate base resin. As a result of an experiment in which the content of the silicon fine particles continuously increased, it was confirmed that even when the content of the silicon fine particles continuously increased, the tensile strength and the elongation were improved (see Examples 1 to 10 and Experimental Example 1 of the present invention ). However, as the content of silicon microparticles increased, the peeling force decreased slightly. According to the present invention, the silicon fine particles are contained in an amount of preferably 0.5 to 20 parts by weight, more preferably 3.0 to 20 parts by weight, and still more preferably 4.0 to 20.0 parts by weight based on 100 parts by weight of the acrylate base resin. Most preferably within the range of < RTI ID = 0.0 >

In the present invention, the silicon microparticles may be surface treated or not by heat treatment. The surface treatment is for removing water and contaminants attached to the surface of the silicon fine particles, and is not particularly limited, and various methods known in the art can be used. For example, it is possible to heat-treat or dry at a high temperature. In the present invention, surface-treated silicon microparticles obtained by drying at a temperature of 100 ° C to 150 ° C for 1 hour to 5 hours and removing water or contaminants from the surface are used.

As a result, it was confirmed that the increase in the tensile strength and the elongation rate of the surface-treated silicon microparticles and the surface-treated silicon microparticles increased as the content was increased, but the improvement value of the surface-treated silicon microparticles was larger Examples 1 to 10 and Experimental Example 1 of the invention). It is believed that the physical performance is improved by increasing the bonding force between the surface treated silicon microparticles and the acrylate during the surface treatment.

As described above, the OCA removing film including the silicon fine particles according to one embodiment of the present invention has excellent tensile strength and elongation, has a stable peeling force, and can exhibit excellent properties as an OCA removing film.

In the present invention, the adherend is a small adherend having an area within a range of 50 cm < 2 > to 500 cm < 2 >, and the silicon fine particles have a size ranging from 3.0 mu m to 5.0 mu m, Do.

That is, the adhesive film according to the present invention can be used together with a small and medium-sized display or a touch screen. In particular, when OCA is removed from a small adhered complex having an area within a range of 50 cm 2 to 500 cm 2, (5.0-3.0 μm) and in the range of 4.0-7.0 parts by weight, the OCA removal effect is the most excellent (see Experimental Example 3 and Table 4 of the present invention).

In the present invention, the adherend is a middle or large-sized adherend having an area within a range of 500 cm 2 to 10,000 cm 2, and the silicon fine particle has a size ranging from 3.0 μm to 5.0 μm and may be included within a range of 15 to 20 parts by weight Do.

That is, the adhesive film according to the present invention can be used together with a small-sized, medium-sized or large-sized display or a touch screen. In particular, when removing OCA from a medium or large adhered complex having an area within a range of 500 cm 2 to 10,000 cm 2, The OCA removal effect is most excellent when the size ranges from 3.0 μm to 5.0 μm and is within the range of 15-20 parts by weight (see Experimental Example 3 and Table 5 of the present invention).

In one embodiment of the invention, the adherend may be, but is not limited to, a smart phone, an automotive electrical component, a medium display component module, a large display component module, or a closed touch screen. By removing the optical transparent adhesive using the pressure sensitive adhesive film according to one embodiment of the present invention from the above-mentioned closed touch screen, a smart phone, an automobile electric component, a medium display component module, and a large display component module, Thereby enabling reuse of large-size component modules.

In one embodiment of the present invention, the first substrate and / or the second substrate are formed on the upper and / or lower portions of the adhesive layer to protect the adhesive layer, and any known plastic substrate film may be used without particular limitation And is preferably one or more selected from the group consisting of ester, ethylene, propylene, diacetate, triacetate, styrene, carbonate, methylpentene, sulfone, ether ethyl ketone, imide, fluorine, nylon, acrylate, , Or a polymer comprising a polymer selected from the group consisting of combinations, or copolymeric polymers, and more preferably, PET release film, but may not be limited thereto.

In one embodiment of the present invention, the adhesive layer may further comprise, in addition to the acrylate base resin, a polyfunctional crosslinking agent, a silane coupling agent, a photopolymerization initiator, and / or a molecular weight modifier. For example, the pressure-sensitive adhesive composition may contain 0.005 to 10 parts by weight of a multifunctional crosslinking agent, 0.01 to 3 parts by weight of a silane coupling agent, 0.01 to 10 parts by weight of a photopolymerization initiator, and 0.01 to 10 parts by weight of a molecular weight modifier 0.01 To 1 part by weight. The pressure-sensitive adhesive layer or adhesive composition may further comprise about 0.005 to 10 parts by weight of a multifunctional crosslinking agent based on 100 parts by weight of the acrylate base resin; About 0.01 to 3 parts by weight of a silane coupling agent; About 0.01 to 10 parts by weight of a photopolymerization initiator; About 0.01 to 1 part by weight of a molecular weight modifier; And about 0.5 to 20 parts by weight of silicon fine particles may be mixed to form a pressure sensitive adhesive composition containing silicon fine particles, but the present invention is not limited thereto. Preferably, the adhesive composition comprises about 0.5 parts by weight of a polyfunctional crosslinking agent, about 0.3 parts by weight of a silane coupling agent, about 0.5 parts by weight of a photopolymerization initiator, about 0.015 part by weight of a molecular weight modifier, and about 3 to 5 parts by weight of a silicon fine particle But may not be limited thereto.

In one embodiment of the invention, the acrylate base resin is selected from the group consisting of methyl methacrylate, urethane acrylate, epoxy acrylate, silicone acrylate, ethylhexyl acrylate, butyl acrylate, ethyl acrylate, isobornyl acrylate, Acrylic acid, hydroxyethyl acrylate, hydroxybutyl acrylate, glycidyl methacrylate, glycidyl methacrylate, glycidyl acrylate, behenyl acrylate, ethyl acrylate, lauryl acrylate, stearyl acrylate, But are not limited to, those selected from the group consisting of hydroxyethyl methacrylate, phenoxy acrylate, methyl acrylate, hexanediol diacrylate, and combinations thereof. For example, the acrylate base resin may be selected from those having excellent tensile strength and elongation, and may be a solvent-free ultraviolet curable resin so as to improve the adhesive force of the adhesive film.

In one embodiment of the present invention, the molecular weight of the acrylate base resin may be from about 50 to about 3,000,000, but is not limited thereto. For example, the molecular weight of the acrylate base resin may range from about 50 to about 3,000,000, from about 50 to about 2,000,000, from about 50 to about 1,000,000, from about 50 to about 100,000, from about 50 to about 10,000, from about 50 to about 1,000, But it may be, but not limited to, about 50 to about 100.

In one embodiment of the present invention, the acrylate base resin may be a partially cured or fully cured resin by photopolymerization. Also, the viscosity of the acrylate base resin may preferably be about 2,000 cps to about 7,000 cps, but is not limited thereto. For example, when the viscosity of the acrylate base resin is less than 2,000 cps, syrup (adhesive composition) may flow during film coating, and when the viscosity of the acrylate base resin is more than about 7,000 cps, .

In one embodiment of the invention, the acrylate base resin is selected from the group consisting of ethylhexyl acrylate (EHA), 2-hydroxyethyl acrylate (HEA), isobornyl acrylate (IBOA), and / ). ≪ / RTI > Among them, the acrylate base resin preferably contains about 40 to 90 parts by weight of ethylhexyl acrylate (EHA), about 10 to 30 parts by weight of 2-hydroxyethyl acrylate (HEA), about 15 to 30 parts by weight of isobornyl acrylate (IBOA) And about 5 to about 25 parts by weight of an acrylic acid (AA), although the present invention is not limited thereto. Preferably, the acrylate base resin comprises about 45 to 55 parts by weight of ethylhexyl acrylate (EHA), about 10 to 20 parts by weight of 2-hydroxyethyl acrylate (HEA), about 10 to 20 parts by weight of isobornyl acrylate (IBOA) 15 to 25 parts by weight of acrylic acid (AA) and about 10 to 15 parts by weight of acrylic acid (AA) were mixed and polymerized by adding about 0.5 part by weight of 1-hydroxy-cyclohexylphenylketone as a photopolymerization initiator for about 30 minutes However, the present invention is not limited thereto. More preferably, the acrylate base resin comprises about 50 parts by weight of ethylhexyl acrylate (EHA), about 15 parts by weight of 2-hydroxyethyl acrylate (HEA), about 20 parts by weight of isobornyl acrylate (IBOA) , And about 15 parts by weight of an acrylic acid (AA) were mixed and then about 0.5 part by weight of 1-hydroxy-cyclohexylphenylketone was added as a photopolymerization initiator and photopolymerized for about 30 minutes. have.

In one embodiment of the present invention, the polyfunctional crosslinking agent may be selected from the group consisting of polyenes monomers, polythiol monomers, polyfunctional (meth) acrylates, and combinations thereof. . For example, the polyfunctional crosslinking agent may be one for improving the tensile strength and elongation of the pressure-sensitive adhesive layer, and improving the degree of crosslinking between the compounds contained in the pressure-sensitive adhesive composition. When a monofunctional crosslinking agent is used as the crosslinking agent, the optical transparent adhesive removing function can not be exerted. In one embodiment of the invention, the multifunctional crosslinking agent is selected from the group consisting of triallyl isocyanurate, diaryl maleate, trimethylolpropane tris-thiopropionate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetra Ethylene glycol diacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylol propane diacrylate, trimethylol propane triacrylate, trimethylol propane Dimethacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol di Methacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol trimethacrylate, pen Triacrylate of urethane acrylate, urethane acrylate, urethane acrylate, urea acrylate, urea acrylate, urethane acrylate, urea acrylate, urethane acrylate, urethritol tetramethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexa methacrylate, But are not limited to, those selected from the group consisting of, and combinations thereof.

In one embodiment of the present invention, the tensile strength and elongation of the pressure-sensitive adhesive film may be controlled by controlling the amount of the polyfunctional crosslinking agent contained in the pressure-sensitive adhesive composition. In one embodiment of the present invention, the polyfunctional crosslinking agent may be included in an amount of about 0.005 part by weight to about 10 parts by weight based on 100 parts by weight of the acrylate base resin, but the present invention is not limited thereto. For example, with respect to 100 parts by weight of the acrylate base resin, the polyfunctional crosslinking agent may be used in an amount of from about 0.005 part to about 10 parts, from about 0.005 to about 5 parts, from about 0.005 part to about 1 part, From about 0.005 part to about 0.1 part, from about 0.005 part to about 0.01 part, from about 0.01 part to about 10 parts, from about 0.1 part to about 10 parts, from about 1 part to about 10 parts, May be included in an amount of about 5 parts by weight to about 10 parts by weight, preferably about 0.01 parts by weight to about 5 parts by weight, but the present invention is not limited thereto. Most preferably, the polyfunctional crosslinking agent may be included in an amount of about 0.5 parts by weight, but the present invention is not limited thereto. For example, when the polyfunctional crosslinking agent is contained in an amount of less than about 0.005 part by weight based on 100 parts by weight of the acrylate base resin, an effect of improving tensile strength and elongation can not be expected, and the polyfunctional crosslinking agent is contained in an amount exceeding about 10 parts by weight , The tensile strength and elongation can be rather lowered.

In one embodiment of the invention, the silane coupling agent is selected from the group consisting of? -Glycidoxypropyltrimethoxysilane,? -Glycidoxypropylmethyldiethoxysilane,? -Glycidoxypropyltriethoxysilane, 3- Vinyltrimethoxysilane, vinyltriethoxysilane,? -Methacryloxypropyltrimethoxysilane,? -Methacryloxypropyltriethoxysilane,? -Aminopropyltrimethoxysilane,? -Methacryloxypropyltrimethoxysilane,? -Methacryloxypropyltrimethoxysilane, but are not limited to, those selected from the group consisting of γ-aminopropyltriethoxysilane, 3-isocyanate propyltriethoxysilane, γ-acetoacetate propyltrimethoxysilane, and combinations thereof . For example, the silane-based coupling agent improves the adsorptivity and adhesion of the adhesive film, thereby effectively removing the residue of the optical transparent adhesive.

In one embodiment of the present invention, the silane coupling agent may be included in an amount of about 0.01 part by weight to about 3 parts by weight based on 100 parts by weight of the acrylate base resin, but the present invention is not limited thereto. For example, about 100 parts by weight of the acrylate base resin, the silane coupling agent may be present in an amount of about 0.01 to about 3 parts by weight, about 0.01 to about 2 parts by weight, about 0.01 to about 1 part by weight About 0.01 parts by weight to about 0.1 parts by weight, about 0.1 parts by weight to about 3 parts by weight, about 1 part by weight to about 3 parts by weight, or about 2 parts by weight to about 3 parts by weight, May be from about 0.1 part by weight to about 1 part by weight, but the present invention is not limited thereto. More preferably, the silane-based coupling agent may be included in an amount of about 0.3 part by weight, but the present invention is not limited thereto. For example, when the silane-based coupling agent is contained in an amount of less than about 0.01 part by weight based on 100 parts by weight of the acrylate base resin, the adhesiveness and adhesion of the adhesive film can not be improved. If it is contained in an amount of more than about 3 parts by weight, the adsorptivity and adhesiveness may be deteriorated.

In one embodiment of the present invention, the photopolymerization initiator is selected from the group consisting of benzophenone, N, N'-tetramethyl-4,4'-diaminobenzophenone (Michler's ketone), N, N'- Dimethylaminobenzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2,2-dimethoxy- Methyl-1- (4- (methylthio) phenyl) -2-morpholinopropanone-1, 2-diphenylethan- , 4-diethyl thioxanthone, 2-ethyl anthraquinone and phenanthrene quinone, benzoin ethers such as benzoin methyl ether, benzoin ethyl ether and benzoin phenyl ether, methyl benzoin and ethyl benzoin Benzyl derivatives such as benzoin and benzyl dimethyl ketal, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di Imidazole dimer, 2- (o-fluorophenyl) -4,5-phenylimidazole dimer, 2- (o-methoxyphenyl) (P-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) -5-phenylimidazole dimer Triarylimidazole dimer such as 2- (2,4-dimethoxyphenyl) -4,5-diphenylimidazole dimer, 9-phenylacridine and 1,7 Acridine derivatives such as bis (9,9'-acridinyl) heptane, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, and mixtures thereof It is preferable to use at least one species. The amount of the photopolymerization initiator is not particularly limited, but is preferably 0.01 to 10 parts by weight based on 100 parts by weight of the acrylate base resin. The photopolymerization initiator has a role of inducing curing between double bonds upon irradiation with ultraviolet rays, thereby enhancing the strength and lowering the adhesive strength.

In one embodiment of the invention, the adhesive composition may include additives selected from the group consisting of plasticizers, ultraviolet absorbers, defoamers, antioxidants, colorants, fillers, surfactants, elastic additives, and combinations thereof. The ultraviolet absorber serves to improve the photostability of the adhesive composition. For example, at least one selected from the group consisting of benzotriazole-based, benzophenone-based, and triazine-based, but may not be limited thereto. Preferably, a hydroxyphenylbenzotriazole-based ultraviolet absorber can be used. For example, the ultraviolet absorber may be a linear or branched alkyl ester of 7-9 carbons of 3- (2H-benzotriazol-2-yl) -5- (1,1-dimethylethyl) 4- hydroxybenzenepropanoic acid, 2- (benzotriazol-2-yl) -4- (2,4,4-trimethylpentan-2-yl) phenol, 2- (2'- (2'-hydroxy-3 ', 5'-di-t-butylphenyl) benzotriazole, 2- (2'- Benzotriazole, 2,4-hydroxybenzophenone, 2,4-hydroxy-4-methoxybenzophenone, 2,4-hydroxy-4-methoxybenzophenone-5-sulfonic acid, Phenyl-6- (2-hydroxy-4-methoxyphenyl) -1,3,5-triazine, 2,4- 3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-propoxyphenyl) Hydroxy-4-butoxyphenyl) -1,3,5-triazine, and the like. The amount of the adhesive composition to be added to the ultraviolet absorber is preferably 0.001 to 1 part by weight based on 100 parts by weight of the acrylate base resin. Within the above range, the yellowing of the surface of the film after curing can be prevented.

In one embodiment of the present invention, the elastic additive is selected from the group consisting of an acrylic liquid rubber resin, urethane, silicone, latex, CR neoprene styrene butadiene rubber, nitrile butadiene rubber, butadiene rubber, ethylene propylene diene monomer rubber, A material capable of crosslinking reaction by UV, and combinations thereof, but may not be limited thereto.

The elastic additive is an element for improving the yield strength of the tensile strength of the adhesive layer of the acrylate resin and enhances the elasticity of the adhesive. According to one embodiment of the present invention, when the elastic additive is used, it appears that the increase in the yield strength of the OCA removal film is affected. The elastic additive may be selected from, for example, an acrylic liquid rubber resin, a urethane, a silicone, a latex, a chloroprene neoprene styrene butadiene rubber, a nitrile butadiene rubber, a butadiene rubber, an ethylene propylene diene monomer rubber, A material capable of crosslinking by UV, and a mixture thereof can be selected. The amount of the elastic additive is not particularly limited, but is preferably 0.1 to 5 parts by weight based on 100 parts by weight of the acrylate base resin.

In one embodiment of the present invention, the molecular weight regulator may be molecular weight regulator, particle size regulator, and may be 3-mercaptopropionic acid (MERCAPTO PROPIONIC ACID). For example, the 3-mercaptopropionic acid (MERCAPTO PROPIONIC ACID) may comprise about 0.01 to 1 part by weight, preferably about 0.015 part by weight.

In one embodiment of the present invention, the acrylate base resin may have a viscosity within the range of 2,000 cps to 5,000 cps. For example, the viscosity of the acrylate based resin may range from about 2,000 cps to about 5,000 cps, from about 2,500 cps to about 5,000 cps, from about 3,000 cps to about 5,000 cps, from about 4,000 cps to about 5,000 cps, cps, from about 2,000 cps to about 4,500 cps, from about 2,000 cps to about 4,000 cps, from about 2,000 cps to about 3,500 cps, or from about 2,000 cps to about 3,000 cps, and preferably from about 2,000 cps to about 2,500 cps However, the present invention is not limited thereto.

In one embodiment of the disclosure, the pressure-sensitive adhesive composition may have a viscosity at 25 DEG C of from about 4,000 cps to about 6,500 cps, but is not limited thereto. For example, the viscosity of the adhesive composition can be from about 4,000 cps to about 6,500 cps, from about 4,000 cps to about 6,000 cps, from about 4,000 cps to about 5,000 cps, from about 4,000 cps to about 4,500 cps, at about room temperature (about 25 ° C) Can be from about 4,500 cps to about 6,500 cps, from about 5,000 cps to about 6,500 cps, from about 5,500 cps to about 6,500 cps, or from about 6,000 cps to about 6,500 cps, and preferably from about 4,000 cps to about 4,500 cps, But may not be limited. By controlling the viscosity of the composition within the above range, process efficiency and physical properties after curing can be effectively maintained. If the viscosity of the composition is less than 2,500 cps, the coating property is good but it may not be easy to form a thick film. If the viscosity exceeds 4,500 cps, the applicability of the pressure-sensitive adhesive is poor and it is difficult to form a uniform film.

2 is a flowchart showing a method for producing an adhesive film for removing an optical transparent adhesive (OCA) containing silicon fine particles according to an embodiment of the present invention.

The pressure-sensitive adhesive film according to one embodiment of the present invention includes steps of obtaining silicon fine particles (S10), obtaining an acrylate base resin (S20), obtaining a pressure sensitive adhesive composition containing silicon fine particles (S30) (S40). The step (S10) of obtaining the silicon fine particles and the step (S20) of obtaining the acrylate base resin may be carried out in any order or simultaneously.

Specifically, an adhesive film for removing optical transparent adhesive (OCA) containing silicon fine particles can be produced by the following method.

The step (S10) of obtaining the silicon fine particles is to prepare silicon fine particles, and the surface of the silicon fine particles can be selectively treated.

The method for preparing the silicon microparticles is not particularly limited. In the surface treatment of the silicon fine particles, the silicon fine particles may be dried in an oven at about 120 ° C. for about 3 hours to conduct a heat treatment step of removing moisture or contaminants attached to the surface of the silicon fine particles. Then, a solution prepared by mixing 0.4 wt% of a silane coupling agent TEOS (tetraethyl orthosilicate) and MeOH and DI (de-ionized water: pure water) in a ratio of 95: 1 was added until the pH reached 4 to form a silanol group The mixture can be stirred for about 1 hour. The agitated silicon fine particles are centrifuged and washed three times, and then the dewatered silicon fine particles are dried in an oven at about 120 ° C for about 3 hours to obtain surface-treated silicon fine particles.

The step (S20) of obtaining the acrylate base resin may be carried out by mixing ethylhexyl acrylate (EHA), 2-hydroxyethyl acrylate (HEA), isobornyl acrylate (IBOA), acrylic acid (AA) Followed by photopolymerization in whole or in part to obtain an acrylate base resin.

In one embodiment of the present invention, the step of obtaining the acrylate base resin may be carried out in the presence of a base such as methyl methacrylate, Acrylate, stearyl acrylate, acrylic acid, hydroxyethyl acrylate, isobornyl acrylate, cyclohexyl methacrylate, glycidyl methacrylate, glycidyl acrylate, behenyl acrylate, ethyl acrylate, lauryl acrylate, And a photopolymerization initiator may be mixed with at least one selected from the group consisting of hydroxyethyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, phenoxy acrylate, methyl acrylate, hexanediol diacrylate, and mixtures thereof. For example, 40 to 90 parts by weight of ethylhexyl acrylate (EHA), 10 to 30 parts by weight of 2-hydroxyethyl acrylate (HEA), 15 to 30 parts by weight of isobornyl acrylate (IBOA) (AA) of 5 to 25 parts by weight, and a photopolymerization initiator to obtain an acrylate base resin. Preferably, about 50 parts by weight of ethylhexyl acrylate (EHA), about 15 parts by weight of 2-hydroxyethyl acrylate (HEA), about 20 parts by weight of isobornyl acrylate (IBOA), and about 20 parts by weight of acrylic acid (AA) And about 15 parts by weight of a photopolymerization initiator are mixed and then about 0.5 part by weight of 1-hydroxy-cyclohexylphenylketone is added as a photopolymerization initiator, followed by photopolymerization for about 30 minutes to obtain an acrylate base resin.

Next, the step (S30) of obtaining the pressure-sensitive adhesive composition may include: 0.005 to 10 parts by weight of a multifunctional crosslinking agent based on 100 parts by weight of the acrylate base resin and the acrylate base resin; 0.01 to 3 parts by weight of a silane coupling agent; 0.01 to 10 parts by weight of a photopolymerization initiator; 0.01 to 1 part by weight of a molecular weight modifier; And 0.5 to 20 parts by weight of silicon fine particles are mixed to obtain a pressure sensitive adhesive composition containing silicon fine particles. According to one embodiment of the present application, the adhesive composition is prepared by mixing 0.5 part by weight of a polyfunctional crosslinking agent, 0.3 part by weight of a silane coupling agent, 0.5 part by weight of a photopolymerization initiator, 0.015 part by weight of a molecular weight modifier, and 3 to 5 parts by weight of a silicon fine particle And then cured to obtain a pressure-sensitive adhesive composition.

Finally, the adhesive film forming step (S40) comprises: applying the pressure-sensitive adhesive composition obtained in the step (S30) on the first substrate, curing the ultraviolet rays to form a film, A step of attaching a release-treated second base material to one side of the film to prevent and protect the adhesive film from damage. The coating method can be generally carried out using a bar coater. In mass production, a comma coating is preferable. After coating, it is preferable to completely cure the film using an ultraviolet curing machine. Further, the second base material subjected to the release treatment is adhered to one surface of the adhesive film to which the first base material is not adhered to prevent the adhesive film from being damaged.

According to this, a second aspect of the present invention provides a method for manufacturing a semiconductor device, comprising: obtaining silicon fine particles; 40 to 90 parts by weight of ethylhexyl acrylate (EHA), 10 to 30 parts by weight of 2-hydroxyethyl acrylate (HEA), 15 to 30 parts by weight of isobornyl acrylate (IBOA) and 5 to 30 parts by weight of acrylic acid (AA) To 25 parts by weight, and a photopolymerization initiator to obtain an acrylate base resin; 0.005 to 10 parts by weight of a multifunctional crosslinking agent based on 100 parts by weight of the acrylate base resin and the acrylate base resin; 0.01 to 3 parts by weight of a silane coupling agent; 0.01 to 10 parts by weight of a photopolymerization initiator; 0.01 to 1 part by weight of a molecular weight modifier; And 0.5 to 20 parts by weight of silicon fine particles to obtain a pressure sensitive adhesive composition comprising silicon fine particles; An adhesive film forming step of applying a pressure-sensitive adhesive composition containing the silicon fine particles onto a first substrate and then curing the adhesive film; And attaching a release-treated second base material to one side of the adhesive film to which the first base material is not adhered after the step of forming the adhesive film. .

In one embodiment of the present invention, the step of obtaining the silicon fine particles may be a step of obtaining surface-treated silicon fine particles or surface-untreated silicon fine particles.

In one embodiment of the present invention, the surface-treated silicon fine particles are dried in an oven at 120 ° C. for 3 hours to be thermally treated, and a silane coupling agent TEOS (tetraethyl orthosilicate) 0.4 wt%, MeOH, Adding the mixed solution until the pH becomes 4 to form a silanol group, stirring the mixture for 1 hour, and then centrifuging, dehydrating and drying.

Although the detailed description of the method of manufacturing the pressure-sensitive adhesive film for optical transparent adhesive removal according to the second aspect of the present invention is omitted for the sake of simplicity and clarity of description of the first aspect of the present invention, The contents can be equally applied to the second aspect of the present invention.

According to one embodiment of the present invention, it is not necessary to use any other chemical method or apparatus, and OCA can be transferred to the adhesive film of the present invention by a simple process of attaching and detaching the adhesive film to neatly remove the adhesive film, Since damage can also be prevented, it is very effective in activating the recycling of the waste touch screen. In addition, it is effective for removing the adhesive film to a vehicle area of medium and large size.

The present invention may be better understood by the following examples, which are for the purpose of illustrating the invention and are not intended to limit the scope of protection defined by the appended claims.

Manufacturing example  1: Base resin production

50 parts by weight of ethylhexyl acrylate (EHA), 15 parts by weight of 2-hydroxyethyl acrylate (HEA), 20 parts by weight of isobornyl acrylate (IBOA), 0.5 part by weight of acetic acid And 15 parts by weight of ACID (AA) were mixed. Then, 0.5 part by weight of 1-hydroxy-cyclohexyl phenyl ketone (manufactured by BASF, Irgacure 184) as a photopolymerization initiator was added and the mixture was photopolymerized for 30 minutes. Subsequently, oxygen was injected into the reactor to inactivate the initiator to terminate the reaction to obtain a base resin having a molecular weight of 1,000,000.

Example  One

0.5 part by weight of 1,4-butanediol dimethacrylate as a multifunctional crosslinking agent, 0.3 part by weight of 3-isocyanate propyltriethoxysilane as a silane coupling agent, , 0.5 part by weight of 2,2-dimethoxy-1,2-diphenylethan-1-one (BASF, IGACURE 651) as an initiator, And 0.015 part by weight of 3-mercaptopropionic acid as a molecular weight modifier were mixed and UV-polymerized to prepare a resin composition. One part by weight of silicon microparticles having a size of 3 to 5 mu m which had not been subjected to surface treatment was mixed to prepare a coating solution.

The coating solution thus prepared was coated on a polyethylene terephthalate (PET) film having a thickness of 50 탆, which had been subjected to a release treatment, so as to have a resin coating solution of 150 탆, cured by UV irradiation for 5 minutes using a UV curing machine, And a polyethylene terephthalate (PET, Toray) film having a thickness of 50 탆 was adhered thereto to prepare an OCA-removing adhesive film.

Example  2

An acrylate resin composition was prepared in the same manner as in Example 1, and 3 parts by weight of silicon fine particles having a size of 3 to 5 μm, which had not been subjected to surface treatment, were mixed to prepare a coating solution. Respectively.

Example  3

An acrylate resin composition was prepared in the same manner as in Example 1, and 5 parts by weight of silicon fine particles having a size of 3 to 5 탆, which had not been subjected to surface treatment, were mixed to prepare a coating solution. Respectively.

Example  4

An acrylate resin composition was prepared in the same manner as in Example 1, and 10 parts by weight of silicon fine particles having a size of 3 to 5 탆, which had not been subjected to surface treatment, were mixed to prepare a coating solution. Respectively.

Example  5

An acrylate resin composition was prepared in the same manner as in Example 1, and 20 parts by weight of silicon fine particles having a size of 3 to 5 탆, which had not been subjected to surface treatment, were mixed to prepare a coating solution. Respectively.

Example  6

An acrylate resin composition was prepared in the same manner as in Example 1, and 1 part by weight of surface-treated silicon fine particles having a size of 3 to 5 탆 was mixed to prepare a coating solution, thereby preparing an OCA-removing adhesive film.

The surface-treated silicon microparticles having a size of 3 to 5 탆 were prepared by drying the silicon microparticles in an oven at 120 캜 for 3 hours to remove moisture and contaminants from the surface of the silicon microparticles. Then, 0.4 wt% of tetraethyl orthosilicate (TEOS), a solution of MeOH and DI in a ratio of 95: 1 was added until the pH of the solution became 4, and the mixture was stirred for 1 hour. The agitated silicon microparticles are dehydrated by centrifugation and washing three times, and then the dehydrated microparticles are dried in an oven at 120 ° C for 3 hours to obtain surface-treated silicon microparticles.

Example  7

And 3 parts by weight of the surface-treated silicon fine particles having a size of 3 to 5 mu m were mixed together to prepare an OCA-removed pressure-sensitive adhesive film.

Example  8

And 5 parts by weight of the surface-treated silicon fine particles having a size of 3 to 5 탆 were mixed together to prepare an OCA-removing pressure-sensitive adhesive film.

Example  9

And 10 parts by weight of the surface-treated silicon fine particles having a size of 3 to 5 mu m were mixed together to prepare an OCA-removed pressure-sensitive adhesive film.

Example  10

And 20 parts by weight of the surface-treated silicon fine particles having a size of 3 to 5 mu m were mixed in the same manner as in Example 6. [

Example  11

And 5 parts by weight of the surface-treated silicon fine particles having a size of 0.5 to 1 mu m were mixed together to prepare an OCA-removed pressure-sensitive adhesive film.

Example  12

And 5 parts by weight of the surface-treated silicon fine particles having a size of 1 to 3 탆 were mixed together to prepare an OCA-removed pressure-sensitive adhesive film.

Example  13

And 5 parts by weight of the surface-treated silicon fine particles having a size of 5 to 10 mu m were mixed together to prepare an OCA-removed pressure-sensitive adhesive film.

Example  14

And 5 parts by weight of the surface-treated silicon fine particles having a size of 10 to 15 탆 were mixed together to prepare an OCA-removed pressure-sensitive adhesive film.

Example  15

And 5 parts by weight of the surface-treated silicon fine particles having a size of 15 to 20 탆 were mixed.

Comparative Example  One

0.5 part by weight of a multifunctional crosslinking agent, 1,4-butanediol dimethacrylate, 0.3 part by weight of a silane-based coupling agent, 3 parts by weight of isocyanate propyltriethoxysilane, 2 parts by weight of a photopolymerization initiator 2, 0.5 part by weight of 2-dimethoxy-1,2-diphenylethan-1-one (BASF, IGACURE 651) And 0.015 part by weight of mercaptopropionic acid were mixed to prepare a pressure-sensitive adhesive composition coating solution.

The coating solution thus prepared was coated on a polyethylene terephthalate (PET) film having a thickness of 50 탆, which had been subjected to a release treatment, so as to have a resin coating solution of 150 탆, cured by UV irradiation for 5 minutes using a UV curing machine, And a polyethylene terephthalate (PET, Toray) film having a thickness of 50 탆 was adhered thereto to prepare an OCA-removing adhesive film.

Comparative Example  2

In Comparative Example 1, 10 parts by weight of spherical silica having a size of 100 nm was further mixed to prepare a coating solution. Using the same, OCA-removing adhesive films were prepared in the same manner as in Comparative Example 1.

Comparative Example  3

In Comparative Example 1, 20 parts by weight of spherical silica having a size of 100 nm was further mixed to prepare a coating solution. Using the same, OCA-removing adhesive films were prepared in the same manner as in Comparative Example 1.

Comparative Example  4

In Comparative Example 1, 20 parts by weight of a liquid acrylic rubber resin was further mixed to prepare a coating solution. Using the same, OCA-removing adhesive films were prepared in the same manner as in Comparative Example 1.

Comparative Example  5

In Comparative Example 1, 30 parts by weight of a liquid acrylic rubber resin was further mixed to prepare a coating solution. Using the same, an OCA-removing adhesive film was prepared in the same manner as in Comparative Example 1.

The adhesive films prepared according to Examples 1 to 15 and Comparative Examples 1 to 5 are summarized in Table 1 below.

Experimental Example  1 - tensile strength and Elongation  Measure

Test specimens having a length of 50 mm and a width of 20 mm were taken for each of the adhesive films prepared according to Examples 1 to 15 and Comparative Examples 1 to 5, and the spacing of the tensile tester or the spacing between the test specimens was 30 mm. The tensile strength was measured at a speed of 300 +/- 30 mm / min using an all-purpose material tester, and the value until the test piece was cut was measured.

Accordingly, the tensile strength and elongation of the OCA-removed adhesive films prepared in Examples 1 to 15 and Comparative Examples 1 to 5 were measured, as shown in Table 2 below.

The tensile strength
(kgf / cm2) Elongation
(%) Example 1 19.28 806 Example 2 21.48 941 Example 3 25.36 1,070 Example 4 29.51 1,176 Example 5 33.67 1,254 Example 6 22.33 842 Example 7 25.73 1,003 Example 8 28.18 1,187 Example 9 34.57 1,260 Example 10 39.95 1,304 Example 11 21.43 989 Example 12 23.76 1,040 Example 13 23.42 1,005 Example 14 21.57 996 Example 15 20.06 930 Comparative Example 1 18.45 780 Comparative Example 2 23.74 1,171 Comparative Example 3 32.16 725 Comparative Example 4 15.86 1,140 Comparative Example 5 13.28 966

As a result of the experiment, the tendency of the tensile strength was changed according to the content of silicon fine particles. It was confirmed that when the content of silicon fine particles was increased, the tensile strength and the elongation were improved even when the content was increased.

In Examples 1 to 10, silicon fine particles having a size of 3 to 5 mu m were used. In Examples 1 to 5, silicon microparticles that were not surface-treated, and in Examples 6 to 10, silicon microparticles that had been surface-treated were used. The increase in the tensile strength and the elongation rate of the surface-treated silicon microparticles and the surface-treated silicon microparticles increased as the content was increased, but it was confirmed that the improvement value of the surface-treated silicon microparticles was larger, It is believed that the physical performance is improved by increasing the bonding force between the surface treated silicon fine particles and the acrylate.

In order to confirm the characteristics depending on the size of the surface-treated silicon fine particles, silicon fine particles having particle sizes of 0.5 to 1 탆, 1 to 3 탆, 3 to 5 탆, 5 to 10 탆, 10 to 15 탆, and 15 to 20 탆, , And the best physical properties were obtained when the surface-treated silicon fine particles were used in a particle size of 3 to 5 μm. In the case of the surface-treated silicon fine particles, the silicon fine particles having a particle size of less than 3 탆 or having a particle size of more than 5 탆 are considered to affect the tensile strength and the elongation reduction due to their influence on the contact area upon bonding with acrylate depending on the particle size .

The results are shown in Comparative Examples 1 to 5 in order to confirm tensile strength and elongation characteristics depending on the presence or absence of silicon fine particles and additives. 10 parts by weight of an inorganic filler having a particle size of 100 nm added to a base resin, 20 parts by weight of an inorganic filler having a particle size of 100 nm, 20 parts by weight of a liquid rubber and 30 parts by weight of a liquid rubber were added to a base resin not containing silicon fine particles. As a result, Comparative Example 1, which did not contain silicon fine particles, showed lower values of tensile strength and elongation than OCA-removed adhesive films containing silicon fine particles. In Comparative Examples 2 to 3 in which an inorganic filler was added to the base resin, the tensile strength increased but the elongation decreased. In the case of the comparative example in which the liquid rubber was added, the tensile strength and elongation were lower than those of the surface-untreated silicon fine particles. It seems that silicon fine particles have higher elasticity than inorganic filler and liquid rubber and have an effect on tensile strength and elongation improvement.

Experimental Example  2 - Peel force

The OCA-removed pressure-sensitive adhesive films prepared in Examples 1 to 15 and Comparative Examples 1 to 5 were adhered to a SUS surface and pressed at a weight of 2 kgf / cm, and then left at room temperature for 30 minutes. The peeling speed was 300 mm / min and the 180 degree peel force on the substrate at 25 캜 was measured. The results are shown in Table 3 below.

Peel force
(kgf / 25 mm) Example 1 1.57 Example 2 1.52 Example 3 1.46 Example 4 1.34 Example 5 1.26 Example 6 1.56 Example 7 1.50 Example 8 1.43 Example 9 1.31 Example 10 1.22 Example 11 1.59 Example 12 1.55 Example 13 1.40 Example 14 1.37 Example 15 1.28 Comparative Example 1 1.67 Comparative Example 2 0.82 Comparative Example 3 0.73 Comparative Example 4 3.07 Comparative Example 5 3.43

According to the experimental results, when the inorganic filler content was increased as in Comparative Example 2 and Comparative Example 3, the peeling force was lowered, and when the content of the liquid rubber was increased as in Comparative Example 4 and Comparative Example 5, the peeling force was increased. As shown in the experimental results, it was confirmed that the inorganic filler and the liquid rubber had a large increase or decrease in the peeling force depending on the content, but the variation range of decrease in the silicon fine particles was small. Silicone microparticles are not significantly different in their physical properties with respect to their content, and therefore, there is no difference in peel strength.

On the other hand, the inorganic filler appears to have the property of reducing the peeling force when the inorganic filler is present at a certain amount or more on the surface of the OCA-removing adhesive film, and the peeling force is increased when the liquid rubber is added, The peeling force was found to rise together.

Experimental Example  3 - Adhesive film Removal power  Test

After attaching the OCA removing adhesive films according to Examples 1 to 15 and Comparative Examples 1 to 5 to a smart phone display and a full length electric vehicle, the PET release film was removed after laminating at a pressure of 2 kgf / cm. Then, the OCA removal performance was measured after removing the OCA by pulling the attached OCA removing adhesive film.

Table 4 below shows the results of measuring the removal power of a smartphone display having a small area using the adhesive films of Examples 1 to 15 and Comparative Examples 1 to 5.

Removal of adhesive film (%) Example 1 81 Example 2 88 Example 3 94 Example 4 88 Example 5 81 Example 6 80 Example 7 91 Example 8 95 Example 9 88 Example 10 78 Example 11 80 Example 12 88 Example 13 85 Example 14 84 Example 15 82 Comparative Example 1 78 Comparative Example 2 91 Comparative Example 3 74 Comparative Example 4 90 Comparative Example 5 75

As shown in Table 4, it was confirmed that the ability to remove the adhesive film can be improved by controlling the physical performance depending on the content of the silicon fine particles, the surface treatment oil, and the particle size. In addition, as shown in Example 8, the highest removal performance was obtained when 5 parts by weight of the surface-treated silicon fine particles having a particle size of 3-5 탆 was applied.

On the other hand, in Comparative Example 1, the removal power was not higher than those of Examples in which silicon fine particles were added. This shows that there is a limitation in increasing the removal force by improving the tensile strength and elongation with the acrylic resin alone.

The removal force of Comparative Example 3 was lower than that of Comparative Example 2 because the inorganic filler content increased and the tensile strength increased but the elongation decreased. Therefore, when the tensile strength increases, a large force is applied in the process of removing the OCA removing adhesive film, leading to the display failure of the smartphone.

In Comparative Example 5, the tensile strength and the elongation were decreased, and the adhesive force for removing the adhesive film was reduced. When the tensile strength and the elongation decreased, the OCA film was stretched in the process of being stretched, and the adhesive film was broken because it could not withstand the applied force.

On the other hand, Table 5 below shows the results of measuring the adhesive force of the adhesive films of Examples 1 to 15 and Comparative Examples 1 to 5 on an automobile electric field having a medium and large area.

Removal of adhesive film (%) Example 1 51 Example 2 58 Example 3 64 Example 4 72 Example 5 78 Example 6 61 Example 7 68 Example 8 75 Example 9 80 Example 10 84 Example 11 61 Example 12 64 Example 13 63 Example 14 54 Example 15 51 Comparative Example 1 44 Comparative Example 2 62 Comparative Example 3 48 Comparative Example 4 41 Comparative Example 5 38

As shown in Table 5, OCA-removed adhesive films containing silicone particulates showed higher removal power than OCA-removed adhesive films containing an inorganic filler or liquid rubber in a medium and large area.

As the OCA removal area increases, the pulling force of the OCA removing adhesive film must be strengthened and stretched well. The tensile strength and the elongation should be increased to prevent the OCA removal adhesive film from breaking.

 The removal performance of OCA removal adhesive film showed the best removal power when 20 parts by weight of the surface-treated silicon fine particles having a size of 3 to 5 탆 was applied as in Example 10.

 In Comparative Examples 2 to 3 in which the inorganic filler was added, the tensile strength was increased, but the elongation was decreased, and the adhesive film was broken during pulling.

 In Comparative Examples 4 to 5 in which the liquid rubber was added, the tensile strength and the elongation were low according to the OCA removal area, and the adhesive film was broken in the process of peeling off the adhesive.

 In Example 10, the tensile strength and elongation were high in the experimental results, and the adhesive film was not broken even in the process of peeling off the adhesive.

Therefore, it was confirmed that the silicone fine particles were superior to the inorganic filler and the liquid rubber in the removal performance of the OCA-removing adhesive film.

Although the present invention has been shown and described with respect to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the following claims It will be apparent to those skilled in the art.

Claims (11)

An adhesive film adhered to an optical transparent adhesive (OCA) to remove the optical transparent adhesive from an adherend,
A first substrate;
A second substrate facing the first substrate; And
And an adhesive layer formed between the first substrate and the second substrate,
Wherein the adhesive layer comprises a pressure-sensitive adhesive composition comprising an acrylate base resin and silicon fine particles,
Wherein the silicon fine particles are contained in an amount of from 4.0 to 7.0 parts by weight or from 15 to 20 parts by weight based on 100 parts by weight of the acrylate base resin,
Wherein the silicone fine particles are surface-treated silicon fine particles obtained by drying the silicone fine particles at a temperature of 100 ° C to 150 ° C for 1 hour to 5 hours to remove moisture or contaminants from the surface.
delete delete delete The method according to claim 1,
When the silicon fine particles are contained in the range of 4.0 to 7.0 parts by weight,
Wherein the adherend is a small adherend having an area within a range of 50 cm < 2 > to 500 cm < 2 >.
The method according to claim 1,
When the silicon fine particles are contained in the range of 15 to 20 parts by weight,
Wherein the adherend is a middle- or large-sized adherend having an area within a range of 500 cm 2 to 10,000 cm 2.
delete The method according to claim 1, 5, or 6,
Wherein the acrylate base resin comprises ethylhexyl acrylate (EHA), 2-hydroxyethyl acrylate (HEA), isobornyl acrylate (IBOA), and acrylic acid (AA) Adhesive film for removing transparent adhesive (OCA).
9. The method of claim 8,
Wherein the acrylate base resin comprises 40 to 90 parts by weight of ethylhexyl acrylate (EHA), 10 to 30 parts by weight of 2-hydroxyethyl acrylate (HEA), 15 to 30 parts by weight of isobornyl acrylate (IBOA) And 5 to 25 parts by weight of an acrylic acid (AA).
9. The method of claim 8,
Wherein the pressure-sensitive adhesive composition further comprises a polyfunctional crosslinking agent, a silane coupling agent, a photopolymerization initiator, and a molecular weight modifier.
11. The method of claim 10,
The pressure-sensitive adhesive composition comprises 0.005 to 10 parts by weight of a multifunctional crosslinking agent, 0.01 to 3 parts by weight of a silane coupling agent, 0.01 to 10 parts by weight of a photopolymerization initiator, and 0.01 to 1 part by weight of a molecular weight modifier, based on 100 parts by weight of the acrylate base resin (OCA). ≪ / RTI >

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