Curable composition, protective film, optical element, and liquid crystal display device

Abstract

The present application aims to provide a curable composition which forms a cured product having suitable release peel force and residual tackiness, and cures a pressure-sensitive adhesive composition forming a pressure-sensitive adhesive layer without the need for a curing process by heat or energy rays.

Description

Technical Field

[0001] This application relates to curable compositions, protective films, optical elements, and liquid crystal display devices. Background Technology

[0002] In the manufacturing process of optical materials such as polarizing plates and retardation plates, which are used to constitute a liquid crystal display, a surface protective film is incorporated to protect the surface of the optical materials. This surface protective film is only used during the manufacturing process of the optical materials; it is peeled off and removed from the optical materials when they are mounted onto the liquid crystal display.

[0003] Typically, a surface protective film has the following shape: a pressure-sensitive adhesive layer is formed on one side of an optically transparent polyethylene terephthalate resin film, and a release film is bonded to the pressure-sensitive adhesive layer to protect it. As an example of such a surface protective film, Patent Document 1 (Korean Patent Publication No. 10-2016-0143501) is known.

[0004] As mentioned above, release films are typically used for coating substrates and the like, while also protecting pressure-sensitive adhesive layers.

[0005] Meanwhile, the pressure-sensitive adhesive layer of the surface protective film is usually made of an acrylic composition containing acrylic compounds. The pressure-sensitive adhesive layer is formed by containing a compound in the acrylic composition that undergoes a curing reaction by heat or energy rays, and by properly curing the acrylic composition by irradiation with heat or energy rays under certain conditions.

[0006] [Existing technical documents]

[0007] (Patent Document 1) Korean Patent Publication No. 10-2016-0105354 Summary of the Invention

[0008] Technical issues

[0009] This application aims to provide a curable composition capable of forming a cured product with suitable release peel force and residual adhesion.

[0010] Furthermore, this application aims to provide a curable composition that can cure an acrylic composition forming a pressure-sensitive adhesive layer without the need for a curing process involving heat or energy rays.

[0011] Technical solution

[0012] In the physical properties mentioned in this application, when the measurement temperature affects the physical properties, unless otherwise stated, the relevant physical properties are those measured at room temperature. Furthermore, unless otherwise stated, the unit of temperature is degrees Celsius (°C).

[0013] As used herein, the term "room temperature" refers to the natural temperature without heating or cooling, which can mean any temperature within the range of, for example, 10°C to 30°C, such as a temperature of about 15°C or higher, about 18°C or higher, about 20°C or higher, about 23°C or higher, about 27°C or lower, or 25°C.

[0014] As used herein, the term 'a to b' means 'within the range of a to b, including both a and b'. For example, the fact of containing a parts by weight to b parts by weight has the same meaning as containing within the range of a parts by weight to b parts by weight.

[0015] As used herein, the term "relative humidity" is expressed as the percentage (%) of the ratio of the amount of water vapor contained in the current air per unit volume to the saturated vapor pressure that the unit volume of air can contain at most, and it can be expressed as RH%.

[0016] As used herein, the term "weight-average molecular weight (M w ) and number-average molecular weight (M n ) can be measured using GPC (gel permeation chromatography), and specifically can be measured according to the following physical property measurement methods. In addition, as used herein, the term "polydispersity index (PDI)" is a value (M w ) obtained by dividing the weight-average molecular weight (M n ) by the number-average molecular weight (M w / M n ), which means the molecular weight distribution of the polymer. Specifically, the number-average molecular weight (M n ) and weight-average molecular weight (M w ) can be measured as follows: Place the analyte in a 20 mL vial, dilute it to a concentration of about 20 mg / mL in a THF (tetrahydrofuran) solvent, and then filter the standard sample for calibration and the sample to be analyzed through a syringe filter (pore size: 0.2 μm). In addition, as an analysis program, ChemStation of Agilent technologies can be used, and the number-average molecular weight (M n ) and weight-average molecular weight (M w ) can be obtained by comparing the elution time of the sample with the calibration curve. Here, the polydispersity index (PDI) can be a value obtained by dividing the measured weight-average molecular weight (M w ) by the number-average molecular weight (M n ).

[0017] <GPC measurement conditions>

[0018] Instrument: Agilent Technologies 1200 Series

[0019] Column: TL Mix.A&B using Agilent Technologies

[0020] Solvent: THF

[0021] Column temperature: 40℃

[0022] Sample concentration: 20 mg / mL, 10 μl injection

[0023] MPs 364000, 91450, 17970, 4910, and 1300 were used as standard samples.

[0024] As used herein, the term substitution means that a hydrogen atom bonded to a carbon atom of a compound is replaced by another substituent, wherein there is no particular restriction on the position to be substituted, as long as the position is where the hydrogen atom is substituted (i.e., the position where the substituent can be substituted), and when two or more substituents are substituted, the substituents may be the same as or different from each other.

[0025] As used herein, the term substituent means an atom or group of atoms that substitutes one or more hydrogen atoms in the parent chain of a hydrocarbon. Furthermore, substituents are described below, but are not limited thereto, and unless otherwise stated herein, substituents may be further substituted by the substituents described below or may be substituted without any substituents.

[0026] Unless otherwise described, the term alkyl or alkylene as used herein can refer to a linear or branched alkyl or alkylene having 1 to 20 carbon atoms, or 1 to 16 carbon atoms, or 1 to 12 carbon atoms, or 1 to 8 carbon atoms, or 1 to 6 carbon atoms, or a cyclic alkyl or alkylene having 3 to 20 carbon atoms, or 3 to 16 carbon atoms, or 3 to 12 carbon atoms, or 3 to 8 carbon atoms, or 3 to 6 carbon atoms. Herein, cyclic alkyl or alkylene also includes alkyl or alkylene having only a cyclic structure, and alkyl or alkylene containing a cyclic structure. For example, both cyclohexyl and methylcyclohexyl correspond to cyclic alkyl. Furthermore, for example, alkyl or alkylene groups can be specifically exemplified as (methylene), (ethyl), (n-propyl), (isopropyl), (n-butyl), (isobutyl), (tert-butyl), (sec-butyl), 1-methyl-(butylene), 1-ethyl-(butylene), (n-pentyl), (isopentyl), (neopentyl), (tert-pentyl), (n-hexyl), 1-methyl(pentylene), 2-methyl(pentylene), 4-methyl-2-(pentylene), 3,3 -Dimethyl(butylene)-, 2-ethyl(butylene)-, (n-heptylene)-, 1-methyl(hexylene)-, (n-octylene)-, (tert-octylene)-, 1-methyl(heptylene)-, 2-ethyl(hexylene)-, 2-propyl(pentylene)-, (n-nonylene)-, 2,2-dimethyl(heptylene)-, 1-ethyl(propylene)-, 1,1-dimethyl(propylene)-, (isohexylene)-, 2-methyl(pentylene)-, 4-methyl(hexylene)-, 5-methyl(hexylene)-, etc., but not limited to these. In addition, cycloalkyl or cycloalkylene compounds can be specifically exemplified as (cyclo)propyl, (cyclo)butyl, (cyclo)pentyl, 3-methyl(cyclo)pentyl, 2,3-dimethyl(cyclo)pentyl, (cyclo)hexyl, 3-methyl(cyclo)hexyl, 4-methyl(cyclo)hexyl, 2,3-dimethyl(cyclo)hexyl, 3,4,5-trimethyl(cyclo)hexyl, 4-tert-butyl(cyclo)hexyl, (cyclo)heptyl, (cyclo)octyl, etc., but are not limited thereto.

[0027] Unless otherwise described, the term alkenyl or alkenyl as used herein can refer to linear or branched acyclic alkenyl or alkenyl groups having 2 to 20 carbon atoms, or 2 to 16 carbon atoms, or 2 to 12 carbon atoms, or 2 to 8 carbon atoms, or 2 to 6 carbon atoms, or cyclic alkenyl or alkenyl groups having 3 to 20 carbon atoms, or 3 to 16 carbon atoms, or 3 to 12 carbon atoms, or 3 to 8 carbon atoms, or 3 to 6 carbon atoms. Herein, when alkenyl or alkenyl groups having a cyclic structure are included, they correspond to cyclic alkenyl or alkenyl groups. Furthermore, examples include, for instance, (ethylene), (n-propylene), (isopropylene), (n-butenyl), (isobutylenyl), (tert-butenyl), (sec-butenyl), 1-methyl-(butenyl), 1-ethyl-(butenyl), (n-pentenyl), (isopentenyl), (neopentenyl), (tert-pentenyl), (n-hexenyl), 1-methyl(pentenyl), 2-methyl(pentenyl), 4-methyl-2-(pentenyl), 3,3-dimethyl(ethylene) Butenyl, 2-ethylbutenyl, n-heptenyl, 1-methylhexenyl, n-octenyl, tert-octenyl, 1-methylheptenyl, 2-ethylhexenyl, 2-propylpentenyl, n-nonenyl, 2,2-dimethylheptenyl, 1-ethylpropenyl, 1,1-dimethylpropenyl, isohexenyl, 2-methylpentenyl, 4-methylhexenyl, 5-methylhexenyl, etc., but not limited to these. In addition, cycloalkenyl or cycloene-alkenyl can be specifically exemplified as (cycloene-)propenyl, (cycloene-)butenyl, (cycloene-)pentenyl, 3-methyl(cycloene-)pentenyl, 2,3-dimethyl(cycloene-)pentenyl, (cycloene-)hexenyl, 3-methyl(cycloene-)hexenyl, 4-methyl(cycloene-)hexenyl, 2,3-dimethyl(cycloene-)hexenyl, 3,4,5-trimethyl(cycloene-)hexenyl, 4-tert-butyl(cycloene-)hexenyl, (cycloene-)heptenyl, (cycloene-)octenyl, etc., but are not limited thereto.

[0028] Unless otherwise described, the term ynyl or ynylene as used herein can refer to a linear or branched acyclic ynyl or ynylene having 2 to 20 carbon atoms, or 2 to 16 carbon atoms, or 2 to 12 carbon atoms, or 2 to 8 carbon atoms, or 2 to 6 carbon atoms, or a cyclic ynyl or ynylene having 3 to 20 carbon atoms, or 3 to 16 carbon atoms, or 3 to 12 carbon atoms, or 3 to 8 carbon atoms, or 3 to 6 carbon atoms. Herein, when ynyl or ynylene with a cyclic structure is included, it corresponds to a cyclic ynyl or ynylene. Furthermore, examples include (ethynylene), (n-propynylene), (isopropynylene), (n-butynylene), (isobutynylene), (tert-butynylene), (sec-butynylene), 1-methyl-(butynylene), 1-ethyl-(butynylene), (n-pentynylene), (isopentynylene), (neopentynylene), (tert-pentynylene), (n-hexynylene), 1-methyl(pentynylene), 2-methyl(pentynylene), 4-methyl-2-(pentynylene), 3,3-dimethyl(pentynylene) Butynyl, 2-ethylbutynyl, n-heptyynyl, 1-methylhexynyl, n-octyynyl, tert-octyynyl, 1-methylheptyynyl, 2-ethylhexynyl, 2-propylpentynyl, n-nonynyl, 2,2-dimethylheptyynyl, 1-ethylpropynyl, 1,1-dimethylpropynyl, isohexynyl, 2-methylpentynyl, 4-methylhexynyl, 5-methylhexynyl, etc., but not limited to these. In addition, cycloynyl or cycloynyl groups can be specifically exemplified as (cycloynyl)propynyl, (cycloynyl)butynyl, (cycloynyl)pentynyl, 3-methyl(cycloynyl)pentynyl, 2,3-dimethyl(cycloynyl)pentynyl, (cycloynyl)hexynyl, 3-methyl(cycloynyl)hexynyl, 4-methyl(cycloynyl)hexynyl, 2,3-dimethyl(cycloynyl)hexynyl, 3,4,5-trimethyl(cycloynyl)hexynyl, 4-tert-butyl(cycloynyl)hexynyl, (cycloynyl)heptyynyl, (cycloynyl)octyynyl, etc., but are not limited thereto.

[0029] Alkyl, alkylene, alkenyl, alkenyl, ynyl, and ynylene groups may also optionally be substituted with one or more substituents. In this case, the substituents may be selected from one or more of the following: halogens (chlorine (Cl), iodine (I), bromine (Br), fluorine (F)), aryl, heteroaryl, epoxy, alkoxy, cyano, carboxyl, acryloyl, methacryloyl, acryloyloxy, methacryloyloxy, carbonyl, and hydroxyl, but are not limited thereto.

[0030] As used herein, the term aryl means an aromatic ring from which one hydrogen atom is removed, wherein the aromatic ring may be monocyclic or polycyclic. Unless otherwise described, aryl does not have a particularly limited number of carbon atoms, but may have 6 to 30, 6 to 26, 6 to 22, 6 to 20, 6 to 18, or 6 to 15 carbon atoms. Furthermore, as used herein, the term arylene means an aryl having two bonding sites, i.e., a divalent group. The description of aryl as described above can be applied, except that each arylene is a divalent group. Aryl can be exemplified, for example, phenyl, phenylethyl, phenylpropyl, benzyl, tolyl, xylyl, or naphthyl, but is not limited thereto.

[0031] As used herein, a heteroaryl is an aromatic ring comprising one or more heteroatoms other than carbon, which may specifically comprise one or more heteroatoms selected from nitrogen (N), oxygen (O), sulfur (S), selenium (Se), and tellurium (Te). In this case, the atoms constituting the ring structure of the heteroaryl may be referred to as ring atoms. Furthermore, heteroaryls may comprise monocyclic or polycyclic rings. Unless otherwise described, heteroaryls do not have a particularly limited number of carbon atoms, but may be heteroaryls having 2 to 30 carbon atoms, or 2 to 26 carbon atoms, or 2 to 22 carbon atoms, or 2 to 20 carbon atoms, or 2 to 18 carbon atoms, or 2 to 15 carbon atoms. In another example, heteroaryls do not have a particularly limited number of ring atoms, but may be heteroaryls having 5 to 30, 5 to 25, 5 to 20, 5 to 15, 5 to 10, or 5 to 8 ring atoms. Examples of heteroaryl groups include, for example, thienyl, furanyl, pyrroleyl, imidazolyl, and thiazolyl. azole group, Diazolyl, Triazolyl, Pyridyl, Bipyridyl, Pyrimidinyl, Triazinyl, Acridineyl, Pyridazinyl, Quinolinyl, Quinazolinyl, Quinoxalinyl, Phtharazineyl, Pyridopyrimidinyl, Pyridopyrazinyl, Pyrazenopyrazinyl, Isoquinolinyl, Indoleyl, Carbazoleyl, Benzo[] Azolyl, benzimidazolyl, benzothiazolyl, benzocarbazole, dibenzocarbazole, benzothiophene, dibenzothiophene, benzofuranyl, dibenzofuranyl, benzothiopyrrolyl, dibenzothiopyrrolyl, phenanthrolinel, iso azole group, thiadiazole group, phenthiazin group, phen Azine groups and their condensation structures, etc., but not limited to these.

[0032] Furthermore, as used herein, the term hypoaryl means a heteroaryl group having two bonding sites, i.e., a divalent group. The description of heteroaryls as described above can be applied, except that each hypoaryl group is a divalent group.

[0033] The aryl or heteroaryl group may also optionally be substituted with one or more substituents. In this case, the substituents may be selected from one or more of the following: halogens (chlorine (Cl), iodine (I), bromine (Br), fluorine (F)), aryl, heteroaryl, epoxy, alkoxy, cyano, carboxyl, acryloyl, methacryloyl, acryloyloxy, methacryloyloxy, carbonyl, and hydroxyl, but are not limited thereto.

[0034] A curable composition according to one example of this application may contain a polyorganosiloxane component and a redox catalyst.

[0035] As used herein, a curable composition may comprise components that can be converted into resins through a curing reaction or polymerization reaction, as well as components commonly referred to as resins. Furthermore, a curable composition may itself possess adhesive or pressure-sensitive adhesive properties, and may acquire these properties through reactions such as a curing reaction.

[0036] In addition, the curable composition can be a solvent-based curable composition, a water-based curable composition, or a solvent-free curable composition.

[0037] Furthermore, the curable composition can be an active energy ray (e.g., ultraviolet) curable, a moisture curable, a thermosetting, or a room temperature curable. When the curable composition is an active energy ray curable, curing is carried out by irradiation with an active energy ray, such as ultraviolet light; when it is a moisture curable, curing is carried out by maintaining it at a suitable humidity; when it is a thermosetting, curing is carried out by applying appropriate heat; or when it is a room temperature curable, curing is carried out by maintaining the curable composition at room temperature.

[0038] The curable composition according to one example of this application can cure acrylic compositions. Furthermore, the curable composition can form a cured product by curing the acrylic composition without heat or energy radiation.

[0039] As used herein, the term acrylic composition may mean a composition containing an acrylic compound in an amount of 55% or more, 65% or more, 75% or more, 85% or more, 95% or more, 99% or more, or 100% by weight relative to the total weight.

[0040] Furthermore, as used herein, the term acrylic compounds (or (meth)acrylates) is a term that includes acrylates and methacrylates, specifically referring to acrylic acid, methacrylic acid, derivatives of acrylic acid, or derivatives of methacrylic acid.

[0041] As used herein, the term acrylic compounds (or (meth)acrylates) can be represented by compounds of the following formula A.

[0042] [Formula A]

[0043]

[0044] In formula A above, R1 can be hydrogen or an alkyl group having 1 to 20 carbon atoms. In addition, R2 can be hydrogen or a halogen (fluorine (F), chlorine (Cl), iodine (I), bromine (Br)), an unsubstituted or substituted alkyl group, an unsubstituted or substituted alkenyl group, an unsubstituted or substituted alkynyl group, an unsubstituted or substituted aryl group, an unsubstituted or substituted heteroaryl group, or a hydroxyl group.

[0045] In formula A, when R1 is hydrogen and R2 is hydrogen, it is acrylic acid, and when R1 is methyl and R2 is hydrogen, it is methacrylic acid.

[0046] Furthermore, in Formula A, when R1 is hydrogen and R2 is not hydrogen, it can be called an acrylic acid derivative; and when R1 is methyl and R2 is not hydrogen, it can be called a methacrylic acid derivative.

[0047] Compounds of formula A can be exemplified as, for example, (meth)acrylic acid; alkyl methacrylates, including methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, isooctyl methacrylate, isodecanyl methacrylate, lauryl methacrylate, cyclohexyl methacrylate, dicyclopentyl methacrylate, dicyclopentenyl methacrylate, dicyclopentenoxyethyl methacrylate, and stearyl methacrylate; aryl methacrylates, including phenyl methacrylate, 3-phenoxypropyl methacrylate, and nonylphenol ethylene oxide-modified (meth)acrylates; ether-based (meth)acrylates, including methoxymethyl methacrylate, ethoxymethyl methacrylate, propoxymethyl methacrylate, butoxymethyl methacrylate, isobutoxymethyl methacrylate, and propylene methacrylate. Methoxyethyl ester, ethoxyethyl ester (meth)acrylate, ethylene oxide ester (meth)acrylate, oxetane ester (meth)acrylate, tetrahydrofuran ester (meth)acrylate, tetrahydro-2H-pyran ester (meth)acrylate, ethylene oxide methyl ester (or glycidyl ester (meth)acrylate), oxetane ethyl ester (meth)acrylate, and tetrahydrofuranyl methyl ester (or tetrahydrofurfuryl ester (meth)acrylate); hydroxyl-containing (meth)acrylates Esters, including 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2,3-dihydroxypropyl methacrylate, 2,2-dihydroxyethyl methacrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, alkoxy polyethylene glycol mono(meth)acrylate, and alkoxy polypropylene glycol mono(meth)acrylate; and so on, but not limited thereto.

[0048] The curable composition according to one example of this application may contain a polyorganosiloxane component in an amount of 50% or more, 52% or more, 54% or more, 56% or more, 58% or more, 60% or more, 62% or more, 64% or more, 66% or more, or 68% or more relative to the total weight, or in an amount of 95% or less, 94% or less, 93% or less, or 92% or less. When the polyorganosiloxane component is contained within the above ranges, excellent residual adhesion and suitable release peel strength can be ensured.

[0049] In a curable composition according to one example of this application, the polyorganosiloxane component may comprise a first polyorganosiloxane component represented by Formula 1. The curable composition comprising the first polyorganosiloxane component represented by Formula 1 thereby ensures excellent residual adhesion and suitable release peel strength.

[0050] [Formula 1]

[0051]

[0052] In Equation 1, R1, R7, and R 10 Each of the functional groups can be an alkenyl group, an isocyanate group, or an amino group, having 2 to 20 carbon atoms, 2 to 18 carbon atoms, 2 to 16 carbon atoms, 2 to 14 carbon atoms, 2 to 12 carbon atoms, 2 to 10 carbon atoms, 2 to 8 carbon atoms, 2 to 6 carbon atoms, or 2 to 4 carbon atoms. At least three functional groups in the first polyorganosiloxane component represented by Formula 1 include an alkenyl group, an isocyanate group, or an amino group, thereby ensuring excellent levels of curing properties.

[0053] In Formula 1, R2, R3, R4, R5, R6, R8, and R9 may each independently be an alkyl group having 1 to 20 carbon atoms, 1 to 18 carbon atoms, 1 to 16 carbon atoms, 1 to 14 carbon atoms, 1 to 12 carbon atoms, 1 to 10 carbon atoms, 1 to 8 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, or 1 to 3 carbon atoms; an alkenyl group having 2 to 20 carbon atoms, 2 to 18 carbon atoms, 2 to 16 carbon atoms, 2 to 14 carbon atoms, 2 to 12 carbon atoms, 2 to 10 carbon atoms, 2 to 8 carbon atoms, 2 to 6 carbon atoms, or 2 to 4 carbon atoms; an isocyanate group; or an amino group.

[0054] Furthermore, in Equation 1, m and n can each independently be numbers ranging from 1 to 10,000, 1 to 8,000, 1 to 6,000, 1 to 4,000, 1 to 3,000, 1 to 2,000, or 1 to 1,000. Specifically, in Equation 1, m can be in the range of 1 to 5,000, 10 to 4,500, 50 to 5,000, 100 to 4,500, 500 to 4,000, or 1,000 to 3,000. Furthermore, in Equation 1, n can be in the range of 1 to 100, 2 to 75, 3 to 50, or 4 to 25.

[0055] The weight-average molecular weight of the first polyorganosiloxane component of the curable composition according to one example of this application may be 100,000 g / mol or greater, 125,000 g / mol or greater, 150,000 g / mol or greater, 175,000 g / mol or greater, 200,000 g / mol or greater, 225,000 g / mol or greater, 250,000 g / mol or greater, 275,000 g / mol or greater, or 300,000 g / mol or greater, or 1,000,000 g / mol. 1 or less, 950,000 g / mol or less, 900,000 g / mol or less, 850,000 g / mol or less, 800,000 g / mol or less, 750,000 g / mol or less, 700,000 g / mol or less, 650,000 g / mol or less, 600,000 g / mol or less, 550,000 g / mol or less, 500,000 g / mol or less, 450,000 g / mol or less, or 400,000 g / mol or less. When the first polyorganosiloxane component has a weight-average molecular weight within the above range, suitable viscosity can be ensured, and therefore excellent coating properties can be ensured.

[0056] The polydispersity index (PDI) of the first polyorganosiloxane component of the curable composition according to one example of this application can be in the range of 1 to 5, 1.25 to 3.5, or 1.5 to 2.5. When the first polyorganosiloxane component does not have a polydispersity index within the above range, the content of components with lower molecular weights compared to the desired weight-average molecular weight increases, which may lead to a deterioration in the physical properties of the cured product.

[0057] In a curable composition according to one example of this application, the first polyorganosiloxane component may comprise 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, or 95% or more, or 99.9% or less, 99% or less, or 98% or less, relative to the total weight of the polyorganosiloxane component. When the first polyorganosiloxane component is contained within the above ranges, excellent residual adhesion and suitable release peel force can be ensured.

[0058] In a curable composition according to one example of this application, the polyorganosiloxane component may include a second polyorganosiloxane component represented by Formula 2 below. Because the curable composition includes the second polyorganosiloxane component represented by Formula 2 below, the crosslinking density is improved, thereby ensuring excellent durability.

[0059] [Equation 2]

[0060]

[0061] In Equation 2, R 11 To R 19 Each can be an alkyl group having 1 to 20 carbon atoms, 1 to 18 carbon atoms, 1 to 16 carbon atoms, 1 to 14 carbon atoms, 1 to 12 carbon atoms, 1 to 10 carbon atoms, 1 to 8 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, or 1 to 3 carbon atoms.

[0062] Furthermore, in Equation 2, a and b can each independently be numbers in the range of 1 to 10,000, 1 to 8,000, 1 to 6,000, 1 to 4,000, 1 to 3,000, 1 to 2,000, or 1 to 1,000. More specifically, in Equation 2, a and b can each independently be in the range of 2 to 500, 5 to 250, 10 to 200, 15 to 150, 20 to 100, or 25 to 50.

[0063] According to one example of this application, the weight-average molecular weight of the second polyorganosiloxane component of the curable composition may be 1,000 g / mol or greater, 1,500 g / mol or greater, 2,000 g / mol or greater, 2,500 g / mol or greater, 3,000 g / mol or greater, 3,500 g / mol or greater, 4,000 g / mol or greater, 4,500 g / mol or greater, 5,000 g / mol or greater, 5,500 g / mol or greater, 6,000 g / mol or greater, 6,500 g / mol or greater, 6,500 g / mol or greater. The weight-average molecular weights of the second polyorganosiloxane component within the above ranges are 7,000 g / mol or greater, 7,500 g / mol or greater, or 8,000 g / mol or greater, or 50,000 g / mol or less, 45,000 g / mol or less, 40,000 g / mol or less, 35,000 g / mol or less, 30,000 g / mol or less, 25,000 g / mol or less, 20,000 g / mol or less, 15,000 g / mol or less, or 12,000 g / mol or less. When the second polyorganosiloxane component has a weight-average molecular weight within the above ranges, excellent curability can be ensured.

[0064] The polydispersity index (PDI) of the second polyorganosiloxane component of the curable composition according to one example of this application can be in the range of 1 to 5, 1.25 to 3.5, or 1.5 to 2.5. When the second polyorganosiloxane component has a polydispersity index within the above range, excellent curability, as well as uniform crosslinking density and curability, can be ensured.

[0065] Relative to 100 parts by weight of the first polyorganosiloxane component, the curable composition according to one example of this application may contain a second polyorganosiloxane component in amounts of 0.1 parts by weight or more, 0.25 parts by weight or more, 0.5 parts by weight or more, 0.75 parts by weight or more, 1 part by weight or more, 1.25 parts by weight or more, 1.5 parts by weight or more, 1.75 parts by weight or more, or 2 parts by weight or more, or in amounts of 10 parts by weight or less, 8 parts by weight or less, 6 parts by weight or less, or 4 parts by weight or less. When the second polyorganosiloxane component is contained within the above ranges, a suitable crosslinking density is improved, thereby ensuring excellent durability.

[0066] As described above, the curable composition according to one example of this application may contain a redox catalyst.

[0067] In the manufacturing process of optical materials such as polarizing plates and retardation plates, which are components of liquid crystal displays, a surface protective film is used to protect the surface of the optical materials. The surface protective film includes a release layer and a pressure-sensitive adhesive layer, wherein the pressure-sensitive adhesive layer is typically made of an acrylic composition containing acrylic compounds. Here, in order to prepare the pressure-sensitive adhesive layer, a process is performed to cure the acrylic composition using heat or energy rays.

[0068] According to one example of this application, a curable composition can form a cured product capable of curing an acrylic compound that forms a pressure-sensitive adhesive layer while simultaneously performing a surface protection function. To form a pressure-sensitive adhesive layer using the curable composition, a curing process using heat or energy rays can be omitted from the acrylic composition, and by simplifying this process, productivity can be increased and costs can be reduced.

[0069] The redox catalyst of the curable composition according to an example of this application may comprise one or more of the following: naphthenic acid metal salts, such as cobalt(II) naphthenic acid; acetate hydrate metal salts, such as cobalt(II) acetate tetrahydrate; alkanonic acid metal salts, such as cobalt(II) 2-ethylhexanoate; sulfate hydrate metal salts, such as ferric(II) sulfate hydrate; acetylacetone metal salts, such as ferric(II) acetylacetone; halide metal salts, such as copper(I) chloride; and alcohol metal salts, such as titanium(IV) isopropoxide. In the redox catalyst, the metal salt may be a salt of a transition metal, wherein the transition metal may be, for example, titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), molybdenum (Mo), lead (Pd), silver (Ag), or cadmium (Cd), but is not limited thereto.

[0070] Relative to 100 parts by weight of the polyorganosiloxane component, the curable composition according to one example of this application may contain a redox catalyst in amounts of 0.01 parts by weight or more, 0.05 parts by weight or more, 0.1 parts by weight or more, 0.2 parts by weight or more, 0.3 parts by weight or more, 0.4 parts by weight or more, 0.5 parts by weight or more, 0.6 parts by weight or more, 0.7 parts by weight or more, or 0.8 parts by weight or more, or in amounts of 80 parts by weight or less, 75 parts by weight or less, 70 parts by weight or less, 65 parts by weight or less, 60 parts by weight or less, 55 parts by weight or less, 50 parts by weight or less, or 45 parts by weight or less. When the redox catalyst is contained within the above ranges, excellent residual adhesion and suitable release peel force can be ensured while the acrylic compound forming the pressure-sensitive adhesive layer is cured.

[0071] Relative to 100 parts by weight of the first polyorganosiloxane component, the curable composition according to one example of this application may contain a redox catalyst in amounts of 0.01 parts by weight or more, 0.05 parts by weight or more, 0.1 parts by weight or more, 0.2 parts by weight or more, 0.3 parts by weight or more, 0.4 parts by weight or more, 0.5 parts by weight or more, 0.6 parts by weight or more, 0.7 parts by weight or more, or 0.8 parts by weight or more, or in amounts of 80 parts by weight or less, 75 parts by weight or less, 70 parts by weight or less, 65 parts by weight or less, 60 parts by weight or less, 55 parts by weight or less, 50 parts by weight or less, or 45 parts by weight or less. In particular, when the redox catalyst is combined with the aforementioned first polyorganosiloxane component and contained within the above ranges, excellent residual adhesion and suitable release peel force can be ensured while effectively curing the acrylic compound forming the pressure-sensitive adhesive layer.

[0072] The curable composition according to one example of this application may further comprise a metal catalyst to facilitate the reaction forming the cured product. The metal catalyst may include one or more of aluminum, bismuth, lead, mercury, tin, zinc, platinum, silver, and zirconium as the central metal element. Furthermore, in the metal catalyst, siloxane, ester, ether, or carboxyl groups may also be bonded to the central metal element. The metal catalyst may be, for example, bis[1,3-bis(2-vinyl)-1,1,3,3-tetramethyldisiloxane]platinum (CAS No. 81032-58-8), dibutyltin dilaurate, or dimethyltin diacetate, but is not particularly limited thereto, and may be used without limitation, provided that it is generally applicable in the art.

[0073] Considering the components contained in the curable composition, the metal catalyst is preferably a platinum catalyst containing platinum (Pt) as the central metal element. Furthermore, relative to 100 parts by weight of the polyorganosiloxane component, the curable composition may contain a platinum catalyst in amounts of 0.1 parts by weight or more, 0.5 parts by weight or more, 1 part by weight or more, 1.5 parts by weight or more, 2 parts by weight or more, 2.5 parts by weight or more, or 3 parts by weight or more, or in amounts of 10 parts by weight or less, 9 parts by weight or less, 8 parts by weight or less, 7 parts by weight or less, 6 parts by weight or less, 5 parts by weight or less, or 4 parts by weight or less. Moreover, when the platinum catalyst content meets the above ranges, the curing product formation reaction can be carried out effectively while reducing side reactions.

[0074] The curable composition according to one example of this application may also contain one or two or more of the additives exemplified below to ensure additional physical properties. However, any additive that is generally available in the art is sufficient and is not necessarily limited to the additives exemplified below.

[0075] The curable composition according to one example of this application may further comprise a dispersant. As a dispersant, for example, polyamide amines and their salts, polycarboxylic acids and their salts, modified polyurethanes, modified polyesters, modified poly(meth)acrylates, (meth)acrylate copolymers, naphthalenesulfonic acid formaldehyde condensates, polyoxyethylene alkyl phosphates, polyoxyethylene alkylamines, and pigment derivatives may be used, but any dispersant known in the art may be used without limitation. For example, Disperbyk-1799 (BYK) described above may be used.

[0076] If necessary, the curable composition according to one example of this application may also contain a plasticizer. There are no particular limitations on the type of plasticizer, but one or more of the following may be selected and used, for example: phthalic acid compounds, phosphoric acid compounds, adipic acid compounds, sebacic acid compounds, citric acid compounds, glycolic acid compounds, trimellitic acid compounds, polyester compounds, epoxidized soybean oil, chlorinated paraffin, chlorinated fatty acid esters, fatty acid compounds, and vegetable oils.

[0077] As a phthalic acid compound, one or more of the following may be used: dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, di-n-octyl phthalate, di-2-ethylhexyl phthalate, diisooctyl phthalate, dioctyl phthalate, dinonyl phthalate, diisononyl phthalate, didecyl phthalate, diundecyl phthalate, dilauryl phthalate, ditridecyl phthalate, dibenzyl phthalate, dicyclohexyl phthalate, butyl benzyl phthalate, octyl decyl phthalate, butyl octyl phthalate, octyl benzyl phthalate, n-hexyl n-decyl phthalate, n-octyl phthalate, and n-decyl phthalate. As a phosphoric acid compound, one or more of the following may be used: tricresyl phosphate, trioctyl phosphate, triphenyl phosphate, octyl diphenyl phosphate, tolyl diphenyl phosphate, and trichloroethyl phosphate. As an adipic acid compound, one or more of the following may be used: dibutoxyethoxyethyl adipate (DBEEA), dioctyl adipate, diisooctyl adipate, di-n-octyl adipate, didecyl adipate, diisononyl adipate (DINA), diisodecyl adipate (DIDP), n-octyl n-decyl adipate, n-heptyl adipate, and n-nonyl adipate. As a sebacic acid compound, one or more of the following may be used: dibutyl sebacate, dioctyl sebacate, diisooctyl sebacate, and butyl benzyl sebacate. As a citric acid compound, one or more of the following may be used: triethyl citrate, acetyl triethyl citrate, tributyl citrate, acetyl tributyl citrate, and acetyl trioctyl citrate. As a glycolic acid compound, one or more of methyl phthaloyl ethyl glycolate, ethyl phthaloyl ethyl glycolate, and butyl phthaloyl ethyl glycolate may be used. As a trimellitic acid compound, one or more of trioctyl trimellitate and tri-n-octyl-decyl trimellitate may be used. The polyester compound may be a reaction product selected from butanediol, ethylene glycol, propane-1,2-diol, propane-1,3-diol, polyethylene glycol, glycerol, diacids (selected from succinic acid, succinic anhydride, and hydroxy acid, e.g., hydroxystearic acid).

[0078] If necessary, the curable composition according to one example of this application may also contain a reaction accelerator. The reaction accelerator can perform the function of promoting the polymerization reaction of the curable composition. There are no particular limitations on the type of reaction accelerator, but for example, N,N-dimethyl-p-toluidine (DMPT) may be used.

[0079] If necessary, the curable composition according to one example of this application may contain a viscosity modifier, such as a thixotropic agent, diluent, surface treatment agent, dispersion stabilizer, reaction control agent, or coupling agent, for controlling viscosity, for example, increasing or decreasing viscosity, or for controlling viscosity according to shear force. A thixotropic agent can adjust the viscosity of the curable composition according to shear force. Examples of usable thixotropic agents include pyrolytic silica. A diluent is generally used to reduce the viscosity of the curable composition, and various types of diluents known in the art may be used without limitation if they can exhibit such an effect. A surface treatment agent is used for surface treatment of the filler composition introduced into the cured product of the curable composition, and various types of dispersant stabilizers known in the art may be used without limitation if they can exhibit such an effect. A dispersion stabilizer can be used to stabilize the dispersibility between components in the curable composition, and various types of dispersion stabilizers known in the art may be used without limitation, provided they can exhibit the above-described effects. A reaction control agent can be used to control chemical reactions, such as the curing of the curable composition, and various types of reaction control agents known in the art may be used without limitation, provided they can exhibit the above-described effects. In the case of coupling agents, for example, they can be used to improve the dispersibility between components in a curable composition, and specifically, silane coupling agents can be used, such as Shin-Etsu's KBM403 or KBM-5103. Furthermore, various types of coupling agents known in the art can be used without limitation if they can exhibit the above-mentioned effects.

[0080] The curable composition according to one example of this application can be dispersed in a solvent. As used herein, the term dispersion can mean the state in which the solute is dissolved in the solvent, and can also mean the state in which the solute is uniformly distributed in the solvent, even if the solute is not dissolved therein.

[0081] Considering the composition of the curable composition, the solvent can be suitably an organic solvent. There are no particular limitations if the organic solvent is commonly used in the art, and solvents such as tetrahydrofuran, methyl ethyl ketone, toluene, and heptane, or mixtures thereof, can be used.

[0082] Solvents can be used to the extent that the curable composition is sufficiently dispersed. Specifically, there are no particular limitations, but the solvent can be used in amounts of 500 parts by weight or more, 600 parts by weight or more, 700 parts by weight or more, 800 parts by weight or more, 900 parts by weight or more, 1,000 parts by weight or more, 1,100 parts by weight or more, 1,200 parts by weight or more, 1,300 parts by weight or more, 1,400 parts by weight or more, or 1,500 parts by weight or more, relative to 100 parts by weight of the curable composition.

[0083] As described above, the curable composition according to one example of this application can cure acrylic compositions by combining polyorganosiloxane components and redox catalysts, and possesses a variety of physical properties by ensuring excellent curing characteristics of the acrylic compositions. Furthermore, the curable composition can even cure acrylic compositions without the use of heat and / or active energy rays, and even in such curing, it possesses a variety of physical properties by ensuring excellent curing characteristics.

[0084] According to one example of this application, the curable composition can cure the acrylic composition at a curing temperature of 10°C or higher, 12.5°C or higher, 15°C or higher, 17.5°C or higher, 20°C or higher, or 60°C or lower, 57.5°C or lower, 55°C or lower, 52.5°C or lower, or 50°C or lower.

[0085] The residual tack ratio (A) of a curable composition according to an example of this application is based on the following general equation 1. d The percentage can be 80% or greater, 81% or greater, 82% or greater, 83% or greater, 84% or greater, or 85% or greater. Residual adhesion percentage (A) d There is no specific upper limit to the percentage, but it can be 100% or less, less than 100%, or 99% or less. According to general Equation 1, the residual adhesive percentage (A) d Specifically, this can be measured according to the following physical property measurement methods. That is, by properly curing the acrylic composition, the curable composition can ensure an excellent level of residual adhesion according to the following general equation 1.

[0086] [General Equation 1]

[0087] Residual adhesion rate (A) d ) = A f / A i ×100(%)

[0088] In general equation 1, A i The release peel force of the cured product of the acrylic composition at 25°C, measured at the interface of a PET (polyethylene terephthalate) film with a peel angle of 180 degrees and a peel rate of 0.3 m / min, and A f In measuring A i Then, the cured product of the acrylic composition was reattached to the interface of the PET film, and the release peel force of the cured product of the acrylic composition at 25°C was measured with a peel angle of 180 degrees and a peel rate of 0.3 m / min.

[0089] By properly curing the acrylic composition, the release peel force of the curable composition according to one example of this application, measured at 25°C at a peel angle of 180 degrees and a peel rate of 0.3 m / min at the interface of the PET (polyethylene terephthalate) film with respect to the cured product of the acrylic composition, can be 50 gf / inch or less, 45 gf / inch or less, 40 gf / inch or less, or 35 gf / inch or less, or 10 gf / inch or more, 11 gf / inch or more, 12 gf / inch or more, 13 gf / inch or more, 14 gf / inch or more, or 15 gf / inch or more. Here, the release peel force at 25°C can be specifically measured according to the following physical property measurement methods.

[0090] By properly curing the acrylic composition, the curable composition according to one example of this application can respectively satisfy the unreacted material content (T1 and T2) according to the following general equations 2 and 3 within a specified range.

[0091] For cured products of acrylic compositions cured by a curable composition, the unreacted material content (T1) according to general Equation 2 can be 60% or less, 58% or less, 56% or less, 54% or less, 52% or less, 50% or less, 48% or less, or 46% or less. The lower the lower limit of the unreacted material content (T1), the better the curing properties, so there is no particular limitation on the lower limit, but it can be 0.01% or more, 0.1% or more, or 1% or more. When the unreacted material content (T1) according to the following general Equation 2 meets the above numerical range, it can be ensured that the curable composition, after curing, has the desired release peel strength and residual tack, while ensuring excellent curing properties without heat or energy radiation.

[0092] [General Equation 2]

[0093] T1 = 100 × (W) A -W B ) / W A

[0094] In general equation 2, W A The initial weight of the cured product obtained by curing the acrylic composition at 25°C, and W BThis refers to the subsequent weight of the cured product of the acrylic composition after storing it in an oven at 150°C for 1 hour, having already measured its initial weight. Here, the cured product of the acrylic composition can be formed by allowing it to stand for a curing time sufficient for it to fully cure at 25°C, and specifically, the curing time can be, for example, 10 hours or longer, 11 hours or longer, or 12 hours or longer, or 30 hours or less, 25 hours or less, or 20 hours or less. The curing time can be 12 hours or 20 hours. Furthermore, T1 according to the above general equation 2 can be specifically measured according to the following physical property measurement methods.

[0095] For the cured product of an acrylic composition cured by a curable composition, the unreacted material content (T2) according to the following general equation 3 can be 50% or less, 48% or less, 46% or less, 44% or less, 42% or less, or 40% or less. The lower the lower limit of the unreacted material content (T2), the better the curing properties, so there is no particular limitation on the lower limit, but it can be 0.01% or more, 0.1% or more, or 1% or more. When the unreacted material content (T2) according to the following general equation 3 meets the above numerical range, it can be ensured that the curable composition, after curing, has the desired release peel strength and residual tack, while ensuring excellent curing properties without heat or energy radiation.

[0096] [General Equation 3]

[0097] T2 = 100 × (W) C -W D ) / W C

[0098] In general equation 3, W C The initial weight of the cured product obtained by curing the acrylic composition at 50°C, and W D This refers to the subsequent weight of the cured product of the acrylic composition after storing an initial weight of the cured product in an oven at 150°C for 1 hour. Here, the cured product of the acrylic composition can be formed by allowing it to stand until it is fully cured, and specifically, the curing time can be, for example, 10 hours or longer, 11 hours or longer, or 12 hours or longer, or 30 hours or less, 25 hours or less, or 20 hours or less. The curing time can be 12 hours or 20 hours. Furthermore, T2 according to the above general equation 3 can be specifically measured according to the following physical property measurement methods.

[0099] An acrylic composition according to one example of this application may comprise an acrylic polymer component and an acrylic monomer component. The acrylic polymer component may comprise a polymer formed by the polymerization (or copolymerization) of one or more acrylic compounds. For example, the polymer may be obtained by adding a photoinitiator to a composition comprising an alkyl-containing (meth)acrylate and a hydroxyl-containing (meth)acrylate, followed by photoinitiation. Furthermore, specifically, the polymer may be obtained by setting the weight ratio (K1 / K2) of the alkyl-containing (meth)acrylate (K1) to the hydroxyl-containing (meth)acrylate (K2) to 1 or greater, 1.25 or greater, or 1.5 or greater, or 3 or less, 2.5 or less, or 2 or less.

[0100] The acrylic monomer component may contain one, two, or more acrylic compounds. For example, the acrylic monomer component may contain alkyl-containing (meth)acrylates and hydroxyl-containing (meth)acrylates. For example, relative to the total weight of the acrylic monomer component, the acrylic monomer component may contain alkyl-containing (meth)acrylates in amounts of 50% or more, 55% or more, 60% or more, 65% or more, or 70% or more, or 90% or less, 85% or less, 80% or less, or 75% or less. Furthermore, relative to 100 parts by weight of alkyl-containing (meth)acrylates, the acrylic monomer component may contain hydroxyl-containing (meth)acrylates in amounts of 10 parts by weight or more, 15 parts by weight or more, 20 parts by weight or more, 25 parts by weight or more, or 50 parts by weight or less, 45 parts by weight or less, 40 parts by weight or less, or 35 parts by weight or less.

[0101] In acrylic compositions, acrylic polymer components and acrylic monomer components can be included in appropriate proportions, while being readily cured by a release layer, resulting in a cured product (which can form a pressure-sensitive adhesive layer) with excellent durability and desired pressure-sensitive adhesive strength. Specifically, relative to the total weight of the acrylic composition, the acrylic polymer component can be included in amounts of 5% or more, 6% or more, 7% or more, 8% or more, 9% or more, or 10% or more, or 20% or less, 19% or less, 18% or less, 17% or less, 16% or less, 15% or less, 14% or less, 13% or less, 12% or less, or 11% or less. In addition, specifically, relative to 100 parts by weight of the acrylic polymer component, the acrylic monomer component may be included in amounts of 300 parts by weight or more, 350 parts by weight or more, 400 parts by weight or more, 450 parts by weight or more, 500 parts by weight or more, 550 parts by weight or more, 600 parts by weight or more, 650 parts by weight or more, 700 parts by weight or more, 750 parts by weight or more, 800 parts by weight or more, or 850 parts by weight or more, or 1,500 parts by weight or less, 1,400 parts by weight or less, 1,300 parts by weight or less, 1,200 parts by weight or less, 1,100 parts by weight or less, or 1,000 parts by weight or less.

[0102] Furthermore, the acrylic composition may, as needed, contain additives, wherein the additives may include one or more selected from metal catalysts, dispersants, plasticizers, initiators, and reaction promoters. Metal catalysts, dispersants, plasticizers, and reaction promoters may be suitably selected and used from the examples described above. Initiators may include peroxide compounds, wherein the peroxide compound may be a material that initiates the polymerization reaction of the acrylic composition. The peroxide compound can be, for example, ketone peroxide compounds, such as methyl ethyl ketone peroxide (MEKP), cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, methyl acetoacetate peroxide, and acetylacetone peroxide; hydroperoxide compounds, such as tert-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramenthane hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide; diacyl peroxide compounds, such as acetyl peroxide, isobutyl peroxide, octyl peroxide, decanyl peroxide, lauroyl peroxide, 3,3,5-trimethylhexanoyl peroxide, succinate peroxide, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, and methyl-toluyl peroxide; or acyl peroxide compounds, such as benzoyl peroxide (BPO), but not limited thereto. Furthermore, peroxide compounds can be used in one, two, or more types.

[0103] A protective film according to one embodiment of this application may include a base film and a cured product of a curable composition according to one embodiment of this application. The protective film may include a base film, a pressure-sensitive adhesive layer, and a release layer, wherein the curable composition according to one embodiment of this application can be formed as a release layer, and an acrylic composition can be cured to form a pressure-sensitive adhesive layer.

[0104] The protective film can specifically refer to a protective film used for optical elements. For example, it can be used as a protective film for optical elements such as polarizers, polarizer protective films, retardation films, viewing angle compensation films, and brightness enhancement films. As used herein, the terms polarizer and polarizer plate refer to different objects. That is, a polarizer refers to the film, sheet, or element itself that exhibits polarization function, while a polarizer plate refers to an optical element that includes other components and a polarizer. Other components that can be included in an optical element along with a polarizer can be exemplified as polarizer protective films or retardation layers, but are not limited thereto.

[0105] In addition, protective films can be effectively used to protect the surfaces of optical components such as polarizing plates, delay plates, optical compensation films, reflective sheets and brightness enhancement films. They are used in various optical devices or components or display devices or components such as LCDs, but their uses are not limited to protective films.

[0106] As an example of the protective film included in this application, the base film can be any common film or sheet known in the art. For example, it may include a plastic film, such as a polyester film, such as polyethylene terephthalate or polybutylene terephthalate; a polytetrafluoroethylene film; a polyethylene film; a polypropylene film; a polybutene film; a polybutadiene film; a poly(vinyl chloride) film; or a polyimide film. Such a film may consist of a single layer, or may be laminated with two or more layers, and may optionally further include a functional layer, such as an antifouling layer or an antistatic layer. Furthermore, from the perspective of improving adhesion to the substrate, a surface treatment, such as a primer treatment, may be applied to one or both sides of the substrate.

[0107] There are no particular restrictions on the thickness of the base membrane; it can be selected appropriately according to the application, and it can typically be formed in thicknesses of 5 μm to 500 μm, 5 μm to 250 μm, or 5 μm to 100 μm.

[0108] The pressure-sensitive adhesive layer included in the protective film according to one embodiment of this application can be formed by curing a pressure-sensitive adhesive composition. Furthermore, the pressure-sensitive adhesive composition can be the aforementioned acrylic composition, and the pressure-sensitive adhesive layer can be formed by curing the acrylic composition. Specifically, the pressure-sensitive adhesive layer can be formed by applying it to a release layer, which will be described below, and then curing it. Here, the acrylic composition is the same as described above, so its detailed description will be omitted. Furthermore, there are no particular limitations on the method of applying the acrylic composition, as long as it is commonly used in the art, and for example, there are methods such as blade coating, roller coating, or reverse coating. Moreover, when forming the pressure-sensitive adhesive layer, it is preferable to do so after sufficiently removing bubble-initiating components such as volatile components or reaction residues from within the acrylic composition. Therefore, problems such as: the crosslinking density or molecular weight of the pressure-sensitive adhesive layer being too low, resulting in a decrease in elastic modulus, and bubbles existing between the glass plate and the pressure-sensitive adhesive layer increasing in size at high temperatures, thereby forming diffusers internally, can be prevented.

[0109] There is no particular limitation on the thickness of the pressure-sensitive adhesive layer included in the protective film, which can be, for example, 2 μm to 100 μm or 5 μm to 50 μm.

[0110] According to an example of this application, the residual adhesion ratio (A) of the pressure-sensitive adhesive layer of the protective film is determined according to the following general equation 1. dThe percentage can be 80% or greater, 81% or greater, 82% or greater, 83% or greater, 84% or greater, or 85% or greater. Residual adhesion percentage (A) d There is no specific upper limit to the percentage, but it can be 100% or less, less than 100%, or 99% or less. According to general Equation 1, the residual adhesive percentage (A) d Specifically, this can be measured using the following physical property measurement methods. Furthermore, when the pressure-sensitive adhesive layer of the protective film has a residual adhesion rate within the above range, a protective film with excellent reprocessability can be ensured.

[0111] [General Equation 1]

[0112] Residual adhesion rate (A) d ) = A f / A i ×100(%)

[0113] In general equation 1, A i The release peel force of the pressure-sensitive adhesive layer at 25°C, measured at the interface of the PET (polyethylene terephthalate) film with a peel angle of 180 degrees and a peel rate of 0.3 m / min, and A f In measuring A i After the pressure-sensitive adhesive layer is reattached to the interface of the PET film, the release peel force of the pressure-sensitive adhesive layer at 25°C is measured at a peel angle of 180 degrees and a peel rate of 0.3 m / min.

[0114] According to one example of this application, the release peel force of the pressure-sensitive adhesive layer of the protective film at 25°C, measured at the interface of the PET (polyethylene terephthalate) film with a peel angle of 180 degrees and a peel rate of 0.3 m / min, can be 50 gf / inch or less, 45 gf / inch or less, 40 gf / inch or less, or 35 gf / inch or less, or 10 gf / inch or more, 11 gf / inch or more, 12 gf / inch or more, 13 gf / inch or more, 14 gf / inch or more, or 15 gf / inch or more. Here, the release peel force at 25°C can be specifically measured according to the following physical property measurement methods. Furthermore, when the pressure-sensitive adhesive layer of the protective film has a release peel force at 25°C within the above range, damage to the surface of the adhered object can be prevented during the peeling process, while preventing separation from the adhered object to protect its surface.

[0115] The release layer included in the protective film according to one embodiment of this application can be obtained by curing the curable composition described above according to one embodiment of this application. Here, the method for curing the curable composition is not particularly limited, and it can be cured through a suitable aging process or in a suitable high-temperature environment or under light irradiation. The thickness of the release layer included in the protective film is not particularly limited, and the thickness can be, for example, 10 nm to 10 μm, 10 nm to 1 μm, or 10 nm to 100 nm.

[0116] In the pressure-sensitive adhesive layer of the protective film according to one example of this application, the curing characteristics of the acrylic composition and the physical properties based on the curing characteristics can be determined according to the composition and content ratio of the curable composition according to one example of this application that forms the release layer. Here, as described above, the pressure-sensitive adhesive layer can be formed by curing the acrylic composition, wherein curing can be carried out at a curing temperature of 10°C or higher, 12.5°C or higher, 15°C or higher, 17.5°C or higher, 20°C or higher, or 60°C or lower, 57.5°C or lower, 55°C or lower, 52.5°C or lower, or 50°C or lower. However, this means that the acrylic composition can be cured even at said curing temperature by the cured product (i.e., the release layer) of the curable composition according to one example of this application, and the curing reaction can also be carried out at 60°C or higher, 65°C or higher, 70°C or higher, 75°C or higher, or 80°C or higher (which are temperatures higher than the curing temperature).

[0117] In particular, based on the redox catalyst contained in the release layer, acrylic compositions can undergo excellent curing reactions within the above temperature range without the need for high temperatures or active energy rays (e.g., ultraviolet light).

[0118] The curing properties of acrylic compositions applied to a release layer can be determined by measuring the unreacted material content (Total Mass Loss, TML). The curing properties of the acrylic composition can be determined by the unreacted material contents (T1 and T2) according to the following general equations 2 and 3, and if the unreacted material contents (T1 and T2) are within the specified ranges, the curing properties can be evaluated as excellent.

[0119] For the curing properties of acrylic compositions, the unreacted material content (T1) according to the following general equation 2 can be 60% or less, 58% or less, 56% or less, 54% or less, 52% or less, 50% or less, 48% or less, or 46% or less. The lower the lower limit of the unreacted material content (T1), the better the curing properties. Therefore, there is no particular limitation on the lower limit, but it can be 0.01% or more, 0.1% or more, or 1% or more. For acrylic compositions, when the unreacted material content (T1) meets this range according to the following general equation 2, the desired release peel strength and residual adhesion after curing can be ensured, while excellent curing properties are ensured in the absence of heat or energy radiation.

[0120] [General Equation 2]

[0121] T1 = 100 × (W) A -W B ) / W A

[0122] In general equation 2, W A The initial weight of the cured product obtained by curing the acrylic composition at 25°C, and W B This refers to the subsequent weight of the cured product of the acrylic composition after storing it in an oven at 150°C for 1 hour, having already measured its initial weight. Here, the cured product of the acrylic composition can be formed by allowing it to stand for a curing time sufficient for it to fully cure at 25°C, and specifically, the curing time can be, for example, 10 hours or longer, 11 hours or longer, or 12 hours or longer, or 30 hours or less, 25 hours or less, or 20 hours or less. Furthermore, T1 according to the above general equation 2 can be specifically measured according to the following physical property measurement methods.

[0123] For the curing properties of acrylic compositions, the unreacted material content (T2) according to the following general equation 3 can be 50% or less, 48% or less, 46% or less, 44% or less, 42% or less, or 40% or less. The lower the lower limit of the unreacted material content (T2), the better the curing properties. Therefore, there is no particular limitation on the lower limit, but it can be 0.01% or more, 0.1% or more, or 1% or more. For acrylic compositions, when the unreacted material content (T2) meets this range according to the following general equation 3, the desired release peel strength and residual adhesion after curing can be ensured, while excellent curing properties are ensured in the absence of heat or energy radiation.

[0124] [General Equation 3]

[0125] T2 = 100 × (W) C -W D ) / W C

[0126] In general equation 3, W C The initial weight of the cured product obtained by curing the acrylic composition at 50°C, and W D This refers to the subsequent weight of the cured product of the acrylic composition after storing it in an oven at 150°C for 1 hour, having already measured its initial weight. Here, the cured product of the acrylic composition can be formed by allowing it to stand until it is fully cured, and specifically, the curing time can be, for example, 10 hours or longer, 11 hours or longer, or 12 hours or longer, or 30 hours or less, 25 hours or less, or 20 hours or less. Furthermore, T2 according to the above general equation 3 can be specifically measured according to the following physical property measurement methods.

[0127] According to one embodiment of this application, the optical element can be in a state where a protective film is attached to its surface. For example, the pressure-sensitive adhesive layer of the protective film can be attached to the surface of the optical element, so that the optical element can be protected by a base film for surface protection.

[0128] The optical elements included in the optical components can be exemplified as, for example, polarizers, polarizing plates, polarizer protective films, retardation layers, or viewing angle compensation layers. Here, as a polarizer, for example, a common type known in the art, such as a polyvinyl alcohol polarizer, can be used without limitation.

[0129] A polarizer is a functional film or sheet capable of extracting light vibrating in only one direction from incident light that vibrates in multiple directions. Such a polarizer can be, for example, in which dichroic dyes are adsorbed and oriented on a polyvinyl alcohol-based resin film. The polyvinyl alcohol-based resin constituting the polarizer can be obtained, for example, by gelling a polyvinyl acetate-based resin. In this case, the polyvinyl acetate-based resin that can be used can include not only homopolymers of vinyl acetate but also copolymers of vinyl acetate and other monomers that can copolymerize therewith. Examples of monomers that can copolymerize with vinyl acetate include, but are not limited to, one or a mixture of two or more of the following: unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having ammonium groups. The degree of gelation of the polyvinyl alcohol-based resin is typically from about 85 mol% to 100 mol%, preferably 98 mol% or greater. The polyvinyl alcohol-based resin can also be further modified, and, for example, polyvinyl alcohol formaldehyde or polyvinyl alcohol acetal modified to aldehydes can also be used. The degree of polymerization of polyvinyl alcohol-based resins is typically around 1,000 to 10,000, preferably around 1,500 to 5,000.

[0130] Polyvinyl alcohol (PVA)-based resins can be formed into a disc-shaped film and used as a polarizer. There are no particular limitations on the film-forming method of the PVA-based resin, and general methods known in the art can be used. The thickness of the disc-shaped film formed from the PVA-based resin is not particularly limited, and can be suitably controlled, for example, in the range of 1 μm to 150 μm. Considering ease of stretching, the thickness of the disc-shaped film can be controlled to 10 μm or greater. The polarizer can be produced by: stretching the above PVA-based resin film (e.g., uniaxial stretching); dyeing the PVA-based resin film with a dichroic dye and adsorbing the dichroic dye; treating the PVA-based resin film adsorbed with a boric acid aqueous solution; and a washing process after treatment with the boric acid aqueous solution, etc. Here, iodine or dichroic organic dyes can be used as the dichroic dye.

[0131] A polarizing plate may include, for example, a polarizer; and other optical films attached to one or both sides of the polarizer. Examples of other optical films include the aforementioned polarizer protective film or retardation layer, viewing angle compensation layer, and anti-glare layer.

[0132] Here, as distinct from the concept of a protective film containing a pressure-sensitive adhesive layer, a polarizer protective film is a protective film used for polarizers. A polarizer protective film can be formed from a multilayer film in which a protective film is laminated, said multilayer film being composed of, for example, cellulose-based films, such as triacetyl cellulose; acrylic films; polyester-based films, such as polycarbonate films or polyethylene terephthalate films; polyethersulfone-based films; and / or polyolefin-based films, such as polyethylene films, polypropylene films, or polyolefin films having cyclic or norbornene structures, or ethylene-propylene copolymers, etc. The thickness of the protective film is not particularly limited, and it can be formed to a typical thickness.

[0133] In optical elements, a surface treatment layer can be present on the surface of the optical element protected by a protective film. The surface treatment layer can have a surface energy of, for example, 30 mN / m or less. That is, in an optical element, a surface treatment layer with a surface energy of 30 mN / m or less can be formed on the surface of the optical element protected by a protective film, and the pressure-sensitive adhesive layer of the protective film can be attached to the surface treatment layer. Here, there are no particular limitations on the method used to measure the surface energy, and known methods for measuring surface energy can be applied. For example, the surface energy can be obtained by measuring the contact angle of the surface of the optical element, or the surface energy can be measured using a known surface energy measuring device.

[0134] Surface treatment layers can be exemplified as high-hardness layers, anti-glare layers such as AG (anti-glare) layers or SG (semi-glare) layers, or low-reflection layers such as AR (anti-reflection) layers or LR (low-reflection) layers.

[0135] High-hardness layers can be layers with a pencil hardness of 1H or higher, or 2H or higher, under a 500g load. Pencil hardness can be measured, for example, using pencil lead as specified in KS G2603 according to ASTM D 3363 standard.

[0136] The high-hardness layer can be, for example, a resin layer with high hardness. The resin layer can comprise, for example, a room-temperature curable, moisture-curable, thermosetting, or radioactively irradiated resin composition in a cured state. In one example, the resin layer can comprise a thermosetting or radioactively irradiated resin composition, or a radioactively irradiated resin composition in a cured state. In the description of the high-hardness layer, "cured state" can mean the condition where the components contained in each resin composition undergo a crosslinking or polymerization reaction to transform the resin composition into a hard state. Furthermore, room-temperature curable, moisture-curable, thermosetting, or radioactively irradiated resin compositions can mean compositions in which the curing state can be initiated at room temperature, or can be initiated in the presence of appropriate humidity or by applying heat or radioactive radiation.

[0137] In the art, various resin compositions that can meet the above-mentioned range of pencil hardness in the cured state are known, and those skilled in the art can easily select a suitable resin composition.

[0138] In one example, the resin composition may contain acrylic compounds, epoxy compounds, urethane compounds, phenolic compounds, or polyester compounds as main materials. Here, "compound" can be a monomer, oligomer, or polymer compound.

[0139] In one example, as a resin composition, an acrylic resin composition having excellent optical properties such as transparency and excellent resistance to yellowing can be used, such as an acrylic resin composition that can be cured by active energy rays.

[0140] Acrylic compositions that can be cured by active energy rays may contain, for example, polymer components that can be polymerized by active energy rays and reactive diluent monomers.

[0141] Polymer components can be exemplified as components of oligomers industrially known as so-called active energy linear polymers, such as urethane acrylates, epoxy acrylates, ether acrylates, or ester acrylates, or polymeric substances comprising mixtures of monomers such as (meth)acrylate monomers. Here, (meth)acrylate monomers can be exemplified as alkyl (meth)acrylates, (meth)acrylates having aromatic groups, heterocyclic (meth)acrylates, or alkoxy (meth)acrylates, etc. Various polymeric components for preparing compositions that can be cured by active energy radiation are known in the art, and such compounds can be selected as needed.

[0142] Reactive diluent monomers that can be included in acrylic compositions that can be cured by active energy rays can be exemplified as monomers having one, two or more functional groups that can be cured by active energy rays, such as acryloyl or methacryloyl groups. For example, the aforementioned (meth)acrylate monomers or polyfunctional acrylates can be used as reactive diluent monomers.

[0143] There are no particular restrictions on the selection of the above-mentioned components or the mixing ratio of the selected components used to prepare acrylic compositions that can be cured by active energy rays, and the selection can be adjusted with consideration of the desired hardness and other physical properties of the resin layer.

[0144] As an anti-glare layer such as an AG layer or an SG layer, for example, a resin layer with an uneven surface formed thereon or a resin layer containing particles, wherein the refractive index of the particles is different from the refractive index of the resin layer, can be used.

[0145] Here, as the resin layer, for example, a resin layer for forming a high-hardness layer can be used. In the case of forming an anti-glare layer, it is not necessary to adjust the composition of the resin composition so that the resin layer necessarily exhibits high hardness, but a resin layer can be formed to exhibit high hardness.

[0146] There are no particular limitations on the method of forming an uneven surface on the resin layer. For example, the uneven structure can be achieved by curing the resin composition while the coating of the resin composition is in contact with a mold having the desired uneven structure, or by blending particles of a suitable particle size into the resin composition, and then coating and curing.

[0147] The anti-glare layer can also be formed using particles with a refractive index different from that of the resin layer.

[0148] In one example, the refractive index difference between the particles and the resin layer can be, for example, 0.03 or less, or 0.02 to 0.2. If the refractive index difference is too small, it will hardly cause haze; conversely, if the refractive index difference is too large, a large amount of scattering will occur in the resin layer, increasing haze, but this may lead to a deterioration in light transmittance or contrast characteristics, etc., so this fact can be taken into account when selecting suitable particles.

[0149] The shape of the particles contained in the resin layer is not particularly limited and can be, for example, spherical, elliptical, polyhedral, amorphous, or other shapes. The average diameter of the particles can be from 50 nm to 5,000 nm. In one example, particles with irregularities on their surface can be used as particles. Such particles can have an average surface roughness (Rz) of 10 nm to 50 nm or 20 nm to 40 nm, and / or a maximum height of irregularities formed on the surface of about 100 nm to 500 nm or 200 nm to 400 nm, and a width between irregularities of 400 nm to 1,200 nm or 600 nm to 1,000 nm. Such particles have excellent compatibility with or dispersibility within the resin layer.

[0150] As particles, various inorganic or organic particles can be exemplified. Inorganic particles can be exemplified as silicon dioxide, amorphous titanium dioxide, amorphous zirconium oxide, indium oxide, aluminum oxide, amorphous zinc oxide, amorphous cerium oxide, barium oxide, calcium carbonate, amorphous barium titanate, or barium sulfate, etc., and organic particles can be exemplified as particles containing cross-linked or non-cross-linked products of organic materials, such as acrylic resins, styrene resins, polyurethane resins, melamine resins, benzoguanamine resins, epoxy resins, or silicone resins, but are not limited thereto.

[0151] There are no particular limitations on the content of the irregular structures or particles formed on the resin layer. The shape of the irregular structures or the content of the particles can be controlled so that, in the case of an AG layer, the haze of the resin layer is approximately 5% to 15%, 7% to 13%, or approximately 10%, and in the case of an SG layer, the haze is approximately 1% to 3%. The haze can be measured using a haze meter, such as the HR-100 or HM-150 from Sepung, according to the manufacturer's manual.

[0152] Low-reflection layers, such as AR or LR layers, can be formed by coating with a low-refractive-index material. Various low-refractive-index materials capable of forming low-reflection layers are known, and all of these materials can be appropriately selected and used in optical components. By coating with a low-refractive-index material, a low-reflection layer can be formed with a reflectivity of approximately 1% or less.

[0153] To form the surface treatment layer, materials known in Korean Patent Publication Nos. 2007-0101001, 2011-0095464, 2011-0095004, 2011-0095820, 2000-0019116, 2000-0009647, 2000-0018983, 2003-0068335, 2002-0066505, 2002-0008267, 2001-0111362, 2004-0083916, 2004-0085484, 2008-0005722, 2008-0063107, 2008-0101801 or 2009-0049557 may also be used.

[0154] The surface treatment layer can be formed alone or in combination of two or more. As an example of a combination, a case can be illustrated by first forming a high-hardness layer on the surface of a base layer, and then forming a low-reflection layer on the surface.

[0155] A liquid crystal display (LCD) device according to one embodiment of this application may include a liquid crystal panel, and the aforementioned optical elements may be attached to one or both sides of the liquid crystal panel.

[0156] There are no particular limitations on the type of liquid crystal panel included in the liquid crystal display device. For example, without limiting the type, all known liquid crystal panels can be used, including various passive matrix modes, such as TN (twisted nematic), STN (super-twisted nematic), F (ferroelectric), and PD (polymer-dispersed LCD); various active matrix modes, including two-terminal and three-terminal types; lateral electric field (IPS) mode panels and vertical alignment (VA) mode panels. Furthermore, there are no particular limitations on other types of structures and manufacturing methods besides those included in the liquid crystal display device, and general configurations in the art can be adopted and used without any restrictions.

[0157] Beneficial effects

[0158] This application provides a curable composition capable of forming a cured product with suitable release peel strength and residual adhesion.

[0159] Furthermore, this application can provide a curable composition that can cure an acrylic composition forming a pressure-sensitive adhesive layer without a curing process involving heat or energy rays. Detailed Implementation

[0160] In the following description, the present application will be described with reference to embodiments and comparative examples, but the scope of the present application is not limited to the content presented below.

[0161] <Preparation of Curable Compositions>

[0162] Example 1.

[0163] As the first polyorganosiloxane component, a compound represented by the following formula 1A (KS-847H of Shin-Etsu Silicone) is used, and the weight-average molecular weight (M) of the first polyorganosiloxane component is... w In the range of approximately 300,000 g / mol to 400,000 g / mol.

[0164] [Formula 1A]

[0165]

[0166] In Equation 1A, m is approximately 1,000 to 2,000, and n is approximately 5 to 20.

[0167] As the second polyorganosiloxane component, a compound represented by formula 2A (Shin-Etsu Silicone X-92-122) is used, and the weight-average molecular weight (M) of the second polyorganosiloxane component is... w The concentration ranges from approximately 8,000 g / mol to 12,000 g / mol.

[0168] [Equation 2A]

[0169]

[0170] In Equation 2A, a is approximately 25 to 45, and b is approximately 25 to 45.

[0171] A first polyorganosiloxane component (PS1), a second polyorganosiloxane component (PS2), a platinum catalyst (Ptc, PL-50L of Shin-Etsu Silicone), and a redox catalyst (Rc, iron acetylacetone (III), Sigma-Aldrich) were added to an organic solvent in a weight ratio of 5:0.1:0.15:2 (PS1:PS2:Ptc:Rc) to prepare a curable composition dispersed in an organic solvent.

[0172] As an organic solvent, a mixture of tetrahydrofuran (THF), methyl ethyl ketone (MEK), toluene (T) and n-heptane (H) is used, and in an amount sufficient to adequately disperse the curable composition.

[0173] Example 2.

[0174] In Example 2, a curable composition dispersed in an organic solvent was prepared in the same manner as in Example 1 above, except that the first polyorganosiloxane component (PS1), the second polyorganosiloxane component (PS2), the platinum catalyst (Ptc, PL-50L of Shin-Etsu Silicone), and the redox catalyst (Rc, iron acetylacetone (III), Sigma-Aldrich) used in Example 1 were added to the organic solvent in a weight ratio of 5:0.1:0.15:0.04 (PS1:PS2:Ptc:Rc).

[0175] Example 3.

[0176] In Example 3, a curable composition dispersed in an organic solvent was prepared in the same manner as in Example 1 above, except that the first polyorganosiloxane component (PS1), the second polyorganosiloxane component (PS2), the platinum catalyst (Ptc, PL-50L of Shin-Etsu Silicone), and the redox catalyst (Rc, iron acetylacetone (III), Sigma-Aldrich) used in Example 1 were added to the organic solvent in a weight ratio of 5:0.1:0.15:0.2 (PS1:PS2:Ptc:Rc).

[0177] Example 4.

[0178] In Example 4, a curable composition dispersed in an organic solvent was prepared in the same manner as in Example 1 above, except that the first polyorganosiloxane component (PS1), the second polyorganosiloxane component (PS2), the platinum catalyst (Ptc, PL-50L of Shin-Etsu Silicone), and the redox catalyst (Rc, iron acetylacetone (III), Sigma-Aldrich) used in Example 1 were added to the organic solvent in a weight ratio of 5:0.1:0.15:1 (PS1:PS2:Ptc:Rc).

[0179] Comparative Example 1.

[0180] In Comparative Example 1, a curable composition dispersed in an organic solvent was prepared in the same manner as in Example 1 above, except that the first polyorganosiloxane component (PS1), the second polyorganosiloxane component (PS2), and the platinum catalyst (Ptc, Shin-Etsu Silicone PL-50L) used in Example 1 were added to the organic solvent in a weight ratio of 5:0.1:0.15 (PS1:PS2:Ptc).

[0181] Compare Example 2.

[0182] In Comparative Example 2, a curable composition dispersed in an organic solvent was prepared in the same manner as in Example 1 above, except that the first polyorganosiloxane component (PS1), the second polyorganosiloxane component (PS2), the platinum catalyst (Ptc, PL-50L of Shin-Etsu Silicone), and the redox catalyst (Rc, iron acetylacetone (III), Sigma-Aldrich) used in Example 1 were added to the organic solvent in a weight ratio of 5:0.1:0.15:5 (PS1:PS2:Ptc:Rc).

[0183] Example 5.

[0184] In Example 5, a curable composition dispersed in an organic solvent was prepared in the same manner as in Example 1 above, except that the first polyorganosiloxane component (PS1), the second polyorganosiloxane component (PS2), the platinum catalyst (Ptc, PL-50L of Shin-Etsu Silicone), and the redox catalyst (Rc, cobalt(III) naphthenate) used in Example 1 were added to the organic solvent in a weight ratio of 5:0.1:0.15:2 (PS1:PS2:Ptc:Rc).

[0185] <Manufacturing of Protective Film>

[0186] Protective films were manufactured by using each of the curable compositions prepared in Examples 1 to 5 and Comparative Examples 1 and 2 above.

[0187] Each of the curable compositions prepared in Examples 1 to 5 and Comparative Examples 1 and 2 was applied to one side of each base film and cured at 150°C for 3 minutes to form a release layer on the base film. At this time, the thickness of the release layer was about 50 nm to 80 nm, and a PET (polyethylene terephthalate) film with a thickness of about 50 μm was used as the base film.

[0188] In the following description, an acrylic composition is applied to a release layer to a thickness of approximately 20 μm to 30 μm and then cured to prepare a protective film on which a pressure-sensitive adhesive layer is formed. At this time, acrylic composition A or acrylic composition B is used as the acrylic composition.

[0189] The above acrylic composition A is prepared by the following steps: mixing 2-ethylhexyl acrylate (2-EHA) and hydroxyethyl acrylate (HEA) in a weight ratio of 6:4 (2-EHA:HEA) and then polymerizing them to obtain an acrylic polymer component (AP); mixing hydroxyethyl acrylate (HEA) and butyl acrylate (BA) in a weight ratio of 3:1 (HEA:BA) to obtain an acrylic monomer component (AM); and mixing 1,6-hexanediol diacrylate (HDDA) as a curing agent in a weight ratio of 10:85:1 (AP:AM:HDDA) to obtain a mixture; adding an initiator (cumene hydroperoxide, CHP) to the mixture in an amount of about 1 part by weight relative to the total weight of the mixture; and adding a reducing agent (N,N-dimethyl-p-toluidine, DMPT) to the mixture in an amount of about 0.6 parts by weight relative to the total weight of the mixture.

[0190] Furthermore, the above acrylic composition B is prepared by the following steps: mixing an acrylic polymer component (AP) in which 2-ethylhexyl acrylate (2-EHA) and hydroxyethyl acrylate (HEA) are mixed in a weight ratio of 6:4 (2-EHA:HEA) and then polymerized; mixing an acrylic monomer component (AM) in which hydroxyethyl acrylate (HEA) and glycidyl methacrylate (GMA) are mixed in a weight ratio of 3:1 (HEA:GMA); and mixing a urethane acrylate curing agent (Shin A&C, SUO-1000) as a curing agent in a weight ratio of 10:85:5 (AP:AM:SUO-1000) to obtain a mixture; adding an initiator (methyl ethyl ketone peroxide, MEKP) to the mixture in an amount of about 2 parts by weight relative to the total weight of the mixture; and adding a reducing agent (N,N-dimethyl-p-toluidine, DMPT) to the mixture in an amount of about 0.6 parts by weight relative to the total weight of the mixture.

[0191] Table 1 below shows examples of protective films using curable compositions. Here, the curable composition serves as the release layer of the protective film, and the acrylic composition serves as the pressure-sensitive adhesive layer of the protective film.

[0192] [Table 1]

[0193]

[0194]

[0195] <Methods for Measuring Physical Properties>

[0196] 1. Method for measuring the percentage of unreacted material content (TML, total mass loss)

[0197] (1) Curing conditions at 25℃

[0198] Here, when preparing the protective film, the acrylic composition applied to the release layer is placed at 25°C for 12 or 20 hours to form a pressure-sensitive adhesive layer. A portion of the formed pressure-sensitive adhesive layer is appropriately cut, and a PET (polyethylene terephthalate) film is attached to both sides of the cut pressure-sensitive adhesive layer to prepare a measurement sample.

[0199] The weight (W) of the measured sample A The measurement was performed, and the sample was placed in an oven at 150°C for 1 hour. The weight (W) of the sample after being placed in the oven was recorded. B The unreacted material content (T1) is measured according to the following general equation 2.

[0200] [General Equation 2]

[0201] T1 = 100 × (W) A -W B ) / W A

[0202] In each of Examples 6 to 9 and Comparative Examples 3 and 4, the content of unreacted material (T1) was measured by placing the acrylic composition applied to the release layer at 25°C for 12 hours, and in each of Examples 10 and Comparative Example 5, the content of unreacted material (T1) was measured by placing the acrylic composition applied to the release layer at 25°C for 20 hours.

[0203] (2) Curing conditions at 50℃

[0204] Here, when preparing the protective film, the acrylic composition applied to the release layer is placed at 50°C for 20 hours to form a pressure-sensitive adhesive layer. A portion of the formed pressure-sensitive adhesive layer is appropriately cut, and a PET (polyethylene terephthalate) film is attached to both sides of the cut pressure-sensitive adhesive layer to prepare a measurement sample.

[0205] The weight (W) of the measured sample C The measurement was performed, and the sample was placed in an oven at 150°C for 1 hour. The weight (W) of the sample after being placed in the oven was recorded. D The unreacted material content (T2) is measured according to the following general equation 3.

[0206] [General Equation 3]

[0207] T2 = 100 × (W) C -W D ) / W C

[0208] The results are shown in Tables 2 and 3 below.

[0209] [Table 2]

[0210] category <![CDATA[Unreacted material content (T1, %)]]> Example 6 5.73 Example 7 44.54 Example 8 11.44 Example 9 10.02 Comparative Example 3 89.51 Comparative Example 4 5.24

[0211] [Table 3]

[0212]

[0213] 2. Methods for measuring release peel force and residual adhesion.

[0214] A standard adhesive tape (TESA, TESA7475) with a PET (polyethylene terephthalate) interface was laminated onto the pressure-sensitive adhesive layer of the protective film prepared above, and stored at 70°C for approximately 24 hours. Then, the release peel force (A) was measured simultaneously by peeling the standard tape at 25°C with a peel angle of 180 degrees and a peel rate of 0.3 m / min using a physical property measuring device (Cheminstruments, AR-1000). i Here, the release peel force (A) is measured. i The results are summarized in Table 4 below.

[0215] In addition, after measuring the release peel force, a standard tape (TESA, TESA7475) with a PET (polyethylene terephthalate) interface was laminated onto the pressure-sensitive adhesive layer and stored at 70°C for approximately 24 hours. Then, the subsequent release peel force (A) was measured simultaneously with peeling the standard tape at 25°C using a physical property measuring device (Cheminstruments, AR-1000) at a peel angle of 180 degrees and a peel rate of 0.3 m / min. f ).

[0216] The residual adhesion rate is measured according to the following general equation 1.

[0217] [General Equation 1]

[0218] Residual adhesion rate (A) d ) = A f / A i ×100(%)

[0219] In general equation 1, A i This refers to the aforementioned release peel force (A) i ), and A f This refers to the subsequent release peel force (A) mentioned above. f ).

[0220] The results are shown in Table 4 below.

[0221] [Table 4]

[0222] category Release peel force (gf / inch) <![CDATA[Residual adhesion rate (A d , %)]]> Example 6 31.9 85.97 Example 7 16.5 93.41 Example 8 21.5 91.56 Example 9 22.3 87.32 Comparative Example 3 13.5 97.10 Comparative Example 4 995.4 63.25 Example 10 155.3 77.46

Claims

1. A protective film comprising a base film, a pressure-sensitive adhesive layer, and a release layer, wherein the release layer comprises a cured product of a curable composition, and the pressure-sensitive adhesive layer comprises a cured product of an acrylic composition. The curable composition comprises a polyorganosiloxane component and a redox catalyst, and is used to form a cured product of the acrylic composition that cures without heat or energy radiation. The acrylic composition therein comprises an acrylic compound, and The acrylic compounds include alkyl-containing (meth)acrylates and hydroxyl-containing (meth)acrylates. The polyorganosiloxane component comprises a first polyorganosiloxane component represented by Formula 1: [Formula 1] in, R1, R7 and R 10 Each group can be an alkenyl group, an isocyanate group, or an amino group, having 2 to 20 carbon atoms. R2, R3, R4, R5, R6, R8, and R9 are each independently an alkyl group having 1 to 20 carbon atoms; an alkenyl group having 2 to 20 carbon atoms; an isocyanate group; or an amino group, and m and n are each an independent number in the range of 1 to 10,000. The polyorganosiloxane component comprises a second polyorganosiloxane component represented by Formula 2: [Equation 2] in, R 11 To R 19 Each is independently an alkyl group having 1 to 20 carbon atoms, and a and b are each an independent number in the range of 1 to 10,000. Wherein, the unreacted material content T1 according to the following general equation 2 satisfies 60% or less, and the cured product of the acrylic composition satisfies a release peel force of 50 gf / inch or less at 25°C, measured at the PET film interface with a peel angle of 180 degrees and a peel rate of 0.3 m / min: [General Equation 2] T1 = 100 × (W A -IN B ) / IN A Among them, W A The initial weight of the cured product obtained by curing the acrylic composition at 25°C for 12 or 20 hours, and W B The subsequent weight of the cured product of the acrylic composition after storing the cured product of the acrylic composition, whose initial weight has been measured, in an oven at 150°C for 1 hour.

2. The protective film according to claim 1, wherein the first polyorganosiloxane component is included in an amount of 70% by weight or more relative to the total weight of the polyorganosiloxane component, and the weight-average molecular weight M of the first polyorganosiloxane component is... w In the range of 100,000 g / mol to 1,000,000 g / mol.

3. The protective film according to claim 1, wherein the weight-average molecular weight M of the second polyorganosiloxane component is... w In the range of 1,000 g / mol to 50,000 g / mol.

4. The protective film according to claim 1, wherein the redox catalyst comprises one or more selected from the group consisting of cycloalkanoate metal salts, acetic acid hydrate metal salts, alkanoate metal salts, sulfate hydrate metal salts, acetylacetone metal salts, halide metal salts, and alcohol metal salts.

5. The protective film according to claim 1, wherein the redox catalyst is included in the range of 0.01 parts by weight to 80 parts by weight relative to 100 parts by weight of the polyorganosiloxane component.

6. The protective film according to claim 1, wherein the curable composition further comprises a platinum catalyst.

7. The protective film according to claim 1, wherein the redox catalyst is included in the range of 0.01 parts by weight to 80 parts by weight relative to 100 parts by weight of the first polyorganosiloxane component.

8. The protective film according to claim 1, wherein the residual adhesion ratio A of the cured product of the acrylic composition is determined according to the following general equation 1. d 80% or higher: [General Equation 1] Residual adhesion rate (A) d ) = A f / A i × 100 (%) in, A i The release peel force of the cured product of the acrylic composition at 25°C, measured at the interface of the PET film with a peel angle of 180 degrees and a peel rate of 0.3 m / min, and A f In measuring A i Then, after the cured product of the acrylic composition is reattached to the interface of the PET film, the release peel force of the cured product of the acrylic composition at 25°C is measured with a peel angle of 180 degrees and a peel rate of 0.3 m / min.

9. An optical element wherein the protective film according to claim 1 is attached to one or both sides.

10. A liquid crystal display device, wherein the optical element according to claim 9 is attached to one or both sides of a liquid crystal panel.

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