KR102410121B1 - Adhesive composition, surface protective film and method for manufacturing organic light emitting electronic device - Google Patents

Abstract

The present application relates to a pressure-sensitive adhesive composition, a surface protection film, and a method for manufacturing an organic light emitting electronic device.

Description

Adhesive composition, surface protection film, and organic light emitting electronic device manufacturing method {ADHESIVE COMPOSITION, SURFACE PROTECTIVE FILM AND METHOD FOR MANUFACTURING ORGANIC LIGHT EMITTING ELECTRONIC DEVICE}

The present application relates to a pressure-sensitive adhesive composition, a surface protection film, and a method for manufacturing an organic light emitting electronic device using the surface protection film.

A plastic substrate used as a substrate material for a flexible display has a problem in that gas barrier properties such as moisture and oxygen are remarkably low. Accordingly, in the prior art, a barrier film to which various materials and structures are applied is formed on the substrate to improve the problems of the plastic substrate.

However, as the existing barrier film is not used recently, the development of a surface protection film for a process capable of protecting a thin film encapsulation (TFE) layer during the manufacturing process of a flexible optical device is required. The surface protection film for the process is a film that temporarily protects the thin film encapsulation layer. It is attached to the thin film encapsulation layer during the process to prevent contamination or damage to the surface of the thin film encapsulation layer during the process, and is removed when the process is finished.

The physical properties required for the surface protection film are, first, that the adhesive provided in the surface protection film must be well attached to the surface of the adherend, and can be removed with a low peel force in the removal step to prevent damage to the adherend . Second, it should be possible to prevent contamination of the adherend with a small amount of adhesive residue after removal of the surface protection film.

Registered Patent Publication No. 10-1756828

Conventionally, as a urethane-based adhesive, in order to reduce the adhesive force of the adhesive, a plasticizer was added to control the adhesive force. However, when a plasticizer is added, it is possible to realize low adhesion, but since the plasticizer diffuses to other materials in contact with the product surface and loses it (migration), surface contamination occurs, making it difficult to implement low residue characteristics. . An object of the present invention is to provide a pressure-sensitive adhesive layer in which a low adhesive strength and a low residual amount are realized without including a plasticizer.

An exemplary embodiment of the present specification is a urethane polymer; acrylic polymer; and a curing agent;

The acrylic polymer provides a pressure-sensitive adhesive composition comprising, as a monomer unit, a (meth)acrylate monomer including an alkyl group having 8 or more carbon atoms.

Another embodiment of the present specification is a pressure-sensitive adhesive layer comprising an acrylic polymer,

The acrylic polymer provides a pressure-sensitive adhesive layer comprising, as a monomer unit, a (meth)acrylate monomer including an alkyl group having 8 or more carbon atoms.

An exemplary embodiment of the present specification includes a base film and a base layer comprising a first antistatic layer and a second antistatic layer respectively provided on both surfaces of the base film; and

As a surface protection film comprising a pressure-sensitive adhesive layer provided on the opposite side of the surface on which the base film of the second antistatic layer is provided,

The pressure-sensitive adhesive layer provides a surface protection film that is the above-described pressure-sensitive adhesive layer.

Another exemplary embodiment of the present specification provides a method of manufacturing an organic light emitting electronic device comprising attaching the pressure-sensitive adhesive layer of the above-described surface protection film on an encapsulation layer of an organic light emitting device.

According to the present invention, the adhesion of the adherend to the surface of the adherend is low, and the surface protection film can be removed with a low peeling force. can provide

1 is a substrate layer 110; pressure-sensitive adhesive layer 124; and a surface protection film composed of the protection layer 130 .
2 is a pressure-sensitive adhesive layer 124 from the surface protection film of FIG. 1 ; and a surface protection film composed of the protection layer 130 .
FIG. 3 illustrates a form in which the surface protection film of FIG. 2 is attached to the adherend 140 .
FIG. 4 illustrates a state in which the adherend of FIG. 3 is the organic light emitting device 510 .

Before describing the present invention, some terms are defined.

In the present specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated.

In the present specification, 'p to q' means the range of 'p or more and q or less'.

In the present specification, (meth)acrylate includes both acrylate and methacrylate.

In the present specification, the meaning that the polymer includes the monomer as a monomer unit means that the monomer participates in a polymerization reaction and is included as a repeating unit in the polymer. In the present specification, when it is said that the polymer includes a monomer, it is interpreted the same as that the polymer includes the monomer as a monomer unit.

In the present specification, the term 'polymer' is understood to be used in a broad sense including a copolymer unless otherwise specified as 'homopolymer'.

As used herein, the term "unit derived from a compound" refers to a state in which the compound is polymerized and bound to the polymer, and accordingly, all or part of two or more substituents are removed from the structure of the compound, and the polymer is located at that position. A radical for bonding with other units of may be located.

As used herein, the term “monomer unit” refers to a state in which a corresponding compound is polymerized and bound to a polymer.

In the present specification, the weight average molecular weight (Mw) and the number average molecular weight (Mn) are obtained by using as a standard a monodisperse polystyrene polymer (standard sample) of various polymerization degrees commercially available for molecular weight measurement, and gel permeation chromatography (Gel Permeation). It is a polystyrene conversion molecular weight measured by Chromatography;GPC). In the present specification, the molecular weight means a weight average molecular weight unless otherwise specified.

Hereinafter, it will be described in detail with reference to the drawings so that those of ordinary skill in the art to which the present invention pertains can easily practice the present invention. However, the present invention may be embodied in several different forms and is not limited to the description below.

An exemplary embodiment of the present specification provides a pressure-sensitive adhesive composition.

The pressure-sensitive adhesive composition is a urethane polymer; acrylic polymer; and a curing agent.

Since the pressure-sensitive adhesive composition according to an exemplary embodiment of the present invention includes a urethane polymer and an acrylic polymer, it can be peeled from an adherend even with a low peeling force, and after peeling the pressure-sensitive adhesive layer from the adherend, a pressure-sensitive adhesive layer with a small amount of residue on the surface of the adherend can be implemented.

In an exemplary embodiment of the present invention, as the urethane polymer, a known urethane polymer may be appropriately selected and used within a range that does not reduce the effects of the present invention.

In an exemplary embodiment of the present invention, the urethane polymer refers to a polymer obtained by curing a urethane composition containing a polyol and a polyfunctional isocyanate compound.

As the polyol included in the urethane composition, any suitable polyol may be used as long as it is a compound containing two or more OH groups. In one embodiment, the polyol may include 2 to 6 OH groups, but is not limited thereto.

The polyol included in the urethane composition may be one or two or more. When two or more types of polyols are used, their mixing ratio may be appropriately selected.

The number average molecular weight of the polyol included in the urethane composition may be appropriately selected. In one embodiment, the number average molecular weight of the polyol may be suitably 100 g/mol to 20,000 g/mol, but is not limited thereto.

In one embodiment, the polyol included in the urethane composition may include a bifunctional polyol and a trifunctional polyol. In one embodiment, the ratio of the trifunctional polyol in the polyol included in the urethane composition is 70% to 100% by weight; 80% to 100% by weight; Or it may be 90% by weight to 100% by weight, the ratio of the bifunctional polyol is 0% by weight to 30% by weight; 0% to 20% by weight; or 0 wt% to 10 wt%. In one embodiment, when the polyol includes a trifunctional polyol, it is advantageous to balance the adhesive force and re-peelability of the pressure-sensitive adhesive layer.

In an exemplary embodiment, when the urethane composition includes a trifunctional polyol, the trifunctional polyol includes a polyol having a number average molecular weight of 10,000 g/mol to 15,000 g/mol and a number average molecular weight of 1,000 g/mol to 5,000 A polyol of g/mol may be used together.

In one embodiment, when the urethane composition includes a bifunctional polyol, the number average molecular weight of the bifunctional polyol may be 100 g/mol to 3,000 g/mol.

The polyol included in the urethane composition preferably does not include an additional functional group reactive with an isocyanate group (NC0).

The polyol included in the urethane composition may be, for example, polyacrylic polyol, polyether polyol, polyester polyol, polycaprolactone polyol, polycarbonate polyol, castor oil-based polyol, and combinations thereof, but is not limited thereto.

In one embodiment, when two or more types of polyols are mixed and used, it is easy to adjust the dispersion degree of molecular weight. In one embodiment, the polyol is 50% to 100% by weight of the polyether polyol in the polyol; and 0% to 50% by weight of polyester polyol. In one embodiment, the polyol is 75% to 95% by weight of polyether polyol in the polyol; and 5% to 25% by weight of a polyester polyol.

As the isocyanate compound included in the urethane composition, any suitable polyfunctional isocyanate compound commonly used in the art may be selected and used as long as it is a compound that can be used in the urethanation reaction.

The polyfunctional isocyanate compound includes, for example, polyfunctional aliphatic isocyanate, polyfunctional alicyclic isocyanate, polyfunctional aromatic isocyanate compound, trimethylol propane adduct obtained by modifying polyisocyanate with trifunctional isocyanate, poly A biuret body obtained by reacting isocyanate with water, a trimer having an isocyanurate ring, etc. may be used, but the present invention is not limited thereto.

The polyfunctional aliphatic isocyanate compound is, for example, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 1,2-propylene diisocyanate, 1,3-butylene diisocyanate, dode carmethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and the like.

The polyfunctional alicyclic isocyanate compound is, for example, isophorone diisocyanate (IPDI), 1,4-cyclohexane diisocyanate (CHDI), 4,4'-dicyclohexylmethane diisocyanate (HMDI), bis(isosia) natomethyl) cyclohexane (HXDI), and the like.

The polyfunctional aromatic isocyanate compound is, for example, toluene 2,4-diisocyanate (TDI), toluene 2,6-diisocyanate (TDI), 4,4'-methylene diphenyl diisocyanate (MDI), 2,4 '-Methylene diphenyl diisocyanate (MDI), polymeric methylene diphenyl diisocyanate (PMDI), p-phenylene diisocyanate (PDI), m-phenylene diisocyanate (PDI), naphthalene 1,5-diisocyanate ( NDI), naphthalene 2,4-diisocyanate (NDI), p-xylylene diisocyanate (XDI), 1,3-bis(1-isocyanato-1-methylethyl)benzene (TMXDI), etc. not limited

In an exemplary embodiment of the present specification, two or more isocyanate compounds may be mixed and used in the urethane composition, and in this case, the type and content of two or more isocyanate compounds may be appropriately selected. For example, as the isocyanate compound included in the urethane composition, a mixture of a polyfunctional aromatic isocyanate compound and a polyfunctional aliphatic isocyanate compound may be used.

In the urethane composition, the equivalent ratio (NCO group/OH group) of the OH group of the polyol and the NCO group of the isocyanate compound is 0.1 or more and less than 1. By satisfying the above ratio, OH groups may be present in the urethane polymer formed from the urethane composition.

In the urethane composition, the mixing ratio of the polyol and the isocyanate compound may be appropriately selected.

In one embodiment, the urethane composition may further include other components within a range that does not reduce the effects of the present invention. For example, the urethane composition may further include a catalyst, a plasticizer, an antioxidant, a leveling agent, a solvent, and the like.

As the polymerization method of the urethane polymer, any suitable known method may be selected, and in one embodiment, a method such as solution polymerization may be used.

In an exemplary embodiment, the preferred weight average molecular weight of the urethane polymer may be 60,000 g/mol to 160,000 g/mol. If the weight average molecular weight of the urethane polymer is less than 60,000 g/mol, the urethane polymer is hard and brittle, and if the weight average molecular weight of the urethane polymer is more than 160,000 g/mol, there is a problem in that the urethane polymer is gelled.

In an exemplary embodiment, the hydroxyl value of the urethane polymer is 3 mgKOH/g to 15 mgKOH/g.

In this specification, the hydroxyl value of a compound can be measured by a titration method. The method for measuring the hydroxyl value by titration is as follows. 1 g of the compound to be measured is added to 25.5 g of an acetylation reagent, and the mixture is stirred in an oil bath at 100° C. for 2 hours. After cooling in air for 30 minutes, 10 ml of pyridine is added. Then, 0.5N KOH 50ml (51g), a magnetic bar and 10 drops of a phenolphthalein indicator are added, and 0.5N KOH is titrated until the solution turns pink while stirring on the plate.

Acetylation reagent: A solution of 70 g of phthalic anhydride and 500 g of pyridine

Phenolphthalein indicator: A solution of 0.5 g of phenolphthalein stock solution, 250 g of ethanol and 250 g of distilled water

The hydroxyl value can be calculated by the following formula.

Hydroxyl value = 28.05×(A-B)×F/(sample amount)

A: 0.5N KOH (ml) required for blank

B: 0.5N KOH (ml) required for this test

F : Amount of KOH when titrated with 0.5N KOH after adding magnetic bar and 10 drops of phenolphthalein indicator to 10ml of 1N HCL (ml)

The acrylic polymer includes a (meth)acrylate monomer including an alkyl group having 8 or more carbon atoms as a monomer unit.

In an exemplary embodiment, the acrylic polymer includes a (meth)acrylate monomer including an alkyl group having 8 or more carbon atoms, thereby implementing a pressure-sensitive adhesive layer capable of peeling from an adherend even with a low peeling force.

In one embodiment, the carbon number of the alkyl group of the (meth) acrylate monomer including the alkyl group having 8 or more carbon atoms is preferably 10 or more; or 12 or more.

As long as the number of carbon atoms of the alkyl group included in the (meth)acrylate monomer including the alkyl group having 8 or more carbon atoms is 8 or more, the desired effect of the present invention may be realized, and the upper limit thereof may be appropriately selected. In one embodiment, the number of carbon atoms of the alkyl group included in the (meth)acrylate monomer including the alkyl group may be preferably 25 or less, but is not limited thereto.

In one embodiment, the unit derived from the (meth) acrylate monomer containing the alkyl group may be represented by the following formula (2).

[Formula 2]

In Formula 2,

R ₁₁ is hydrogen or a methyl group,

R ₁₂ is an alkyl group having 8 or more carbon atoms.

In an exemplary embodiment, R ₁₂ is an alkyl group having 10 or more carbon atoms; or an alkyl group having 12 or more carbon atoms.

In one embodiment, R ₁₂ is an alkyl group having 25 or less carbon atoms.

In one embodiment, the (meth) acrylate monomer comprising an alkyl group having 8 or more carbon atoms is, for example, octyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl ( Meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylic Late, heptadecyl (meth) acrylate, stearyl (meth) acrylate, docosyl (meth) acrylate (docosyl (meth) acrylate), behenyl (meth) acrylate (behenyl (meth) acrylate) , but is not limited thereto.

In one embodiment, the pressure-sensitive adhesive composition may include a (meth)acrylate monomer including two or more kinds of alkyl groups having 8 or more carbon atoms. In this case, the mixing ratio of the monomers is not particularly limited, and may be appropriately selected and used.

In an exemplary embodiment of the present specification, the (meth)acrylate monomer including an alkyl group having 8 or more carbon atoms is 1 wt% or more based on the total amount of monomer units included in the acrylic polymer; or 3% by weight or more. When the (meth)acrylate monomer containing an alkyl group having 8 or more carbon atoms is included in less than the above range, the effect of lowering the adhesive strength of the pressure-sensitive adhesive layer may be lowered.

In an exemplary embodiment of the present specification, the (meth)acrylate monomer including an alkyl group having 8 or more carbon atoms is 40% by weight or less based on the total amount of monomer units included in the acrylic polymer; or 35% by weight or less. When the (meth)acrylate containing the alkyl group having 8 or more carbon atoms is included in more than the above range, the compatibility between the acrylic polymer and the urethane polymer is low, and haze may be induced in the pressure-sensitive adhesive layer.

In an exemplary embodiment of the present specification, the acrylic polymer is a (meth) acrylate monomer other than the (meth) acrylate monomer containing an alkyl group having 8 or more carbon atoms and other monomers polymerizable with the (meth) acrylate monomer in a range that does not impair the effects of the present invention It may further include components (other monomers).

In an exemplary embodiment of the present specification, the acrylic polymer may further include (meth)acrylate monomers such as alkyl (meth)acrylate, cyclohexyl (meth)acrylate, aromatic (meth)acrylate having less than 8 carbon atoms. However, the present invention is not limited thereto.

Examples of the alkyl (meth) acrylate having less than 8 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl ( Meth) acrylate, t-butyl (meth) acrylate, sec-butyl (meth) acrylate, pentyl (meth) acrylate, 2-ethylbutyl (meth) acrylate, but is not limited thereto.

Examples of the aromatic (meth)acrylate include orthobiphenyl (meth)acrylate, metabiphenyl (meth)acrylate, parabiphenyl (meth)acrylate, 2,6-terphenyl (meth)acrylate, Ortho-phenyl (meth) acrylate, meth-phenyl (meth) acrylate, para-phenyl (meth) acrylate, 4- (4-methylphenyl) phenyl (meth) acrylate, 4- (2-methylphenyl) phenyl ( Meth) acrylate, 2- (4-methylphenyl) phenyl (meth) acrylate, 2- (2-methylphenyl) phenyl (meth) acrylate, 4- (4-ethylphenyl) phenyl (meth) acrylate, 4- (2-ethylphenyl)phenyl (meth)acrylate, 2-(4-ethylphenyl)phenyl (meth)acrylate, 2-(2-ethylphenyl)phenyl (meth)acrylate, and the like, but is not limited thereto. .

Other (meth) acrylate monomers that may be included in the acrylic polymer include, for example, cyclohexyl (meth) acrylate, phenoxy (meth) acrylate, 2-ethylphenoxy (meth) acrylate, benzyl (meth) Acrylate, phenyl (meth) acrylate, 2-ethylthiophenyl (meth) acrylate, 2-phenylethyl (meth) acrylate, 3-phenylpropyl (meth) acrylate, 4-phenylbutyl (meth) acrylate , 2,2-methylphenylethyl (meth)acrylate, 2,3-methylphenylethyl (meth)acrylate, 2,4-methylphenylethyl (meth)acrylate, 2- (4-propylphenyl)ethyl (meth)acryl rate, 2-(4-(1-methylethyl)phenyl)ethyl(meth)acrylate, 2-(4-methoxyphenyl)ethyl(meth)acrylate, 2-(4-cyclohexylphenyl)ethyl (meth) ) acrylate, 2- (2-chlorophenyl) ethyl (meth) acrylate, 2- (3-chlorophenyl) ethyl (meth) acrylate, 2- (4-chlorophenyl) ethyl (meth) acrylate, 2 -(4-bromophenyl)ethyl (meth)acrylate, 2-(3-phenylphenyl)ethyl (meth)acrylate, and 2-(4-benzylphenyl)ethyl (meth)acrylate, but may be not limited

In one embodiment, the acrylic polymer further includes an alkyl (meth)acrylate monomer having less than 8 carbon atoms in an amount of 60 wt% to 99 wt% based on the total amount of monomer units included in the acrylic polymer.

In one embodiment, the acrylic polymer is an alkyl (meth) acrylate monomer having less than 8 carbon atoms; and a random polymer of an alkyl (meth)acrylate monomer having 8 or more carbon atoms.

In the present specification, the alkyl (meth) acrylate means CH ₂ CR ₃₁ COOR ₃₂ , R ₃₁ is hydrogen; or a methyl group, and R ₃₂ represents an alkyl group. In an exemplary embodiment, the alkyl (meth)acrylate having 8 or more carbon atoms means that R ₃₂ has 8 or more carbon atoms, and the alkyl (meth)acrylate having less than 8 carbon atoms means less than 8 carbon atoms in R ₃₂ .

In an exemplary embodiment, the acrylic polymer includes: 60 wt% to 99 wt% of an alkyl (meth)acrylate monomer having less than 8 carbon atoms; and 1 wt% to 40 wt% of an alkyl (meth)acrylate monomer having 8 or more carbon atoms.

In one embodiment, the acrylic polymer is an alkyl (meth) acrylate monomer having less than 8 carbon atoms 65% to 97% by weight; and 3 wt% to 35 wt% of an alkyl (meth)acrylate monomer having 8 or more carbon atoms.

In the exemplary embodiment of the present specification, the acrylic polymer may be polymerized using various polymerization methods commonly used, such as solution polymerization, peracid polymerization, suspension polymerization, emulsion polymerization, and radiation curing polymerization.

In the present specification, the acrylic polymer is a random copolymer in which monomers are mixed with each other without regularity, a block copolymer in which blocks arranged by a certain section are repeated, or a polymer in which monomers are alternately repeated It may be an alternating copolymer (Alternating Copolymer) having a form that is

In one embodiment, the hydroxyl value of the acrylic polymer is 0mmKOH/g.

In an exemplary embodiment of the present specification, the weight average molecular weight of the acrylic polymer is 10,000 g/mol or more; 15,000 g/mol or more; or 20,000 g/mol or more.

In an exemplary embodiment of the present specification, the weight average molecular weight of the acrylic polymer is 60,000 g/mol or less; 55,000 g/mol or less; 50,000 g/mol or less; or 40,000 g/mol or less.

If the molecular weight of the acrylic polymer is less than 10,000 g/mol, the adhesive may migrate from the pressure-sensitive adhesive layer to the surface of the adherend and cause problems such as contamination, and if the molecular weight of the acrylic polymer is less than 60,000 g/mol, the urethane polymer Since compatibility with the pressure-sensitive adhesive layer can be minimized, it is preferable to satisfy the above range.

In one embodiment of the present specification, the curing agent is an isocyanate-based curing agent.

In an exemplary embodiment of the present specification, the isocyanate-based curing agent may be selected from oligomers, polymers, cyclic monomers, or conventional aliphatic or aromatic diisocyanate compounds of diisocyanate compounds, and commercially available oligomers of diisocyanate compounds. It can be obtained and used.

In an exemplary embodiment of the present specification, the isocyanate-based curing agent is 2,4- or 2,6-toluene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI), xylene diisocyanate (XDI) ), aromatic cyclic diisocyanate compounds having a benzene ring such as 1,5-naphthalene diisocyanate; aliphatic acyclic diisocyanates such as hexamethylene diisocyanate (HDI), propylene diisocyanate, lysine diisocyanate, and 2,2,4- or 2,4,4-trimethylhexamerenediisocyanate; Aliphatic cyclic diisocyanate compounds, such as 1, 4- cyclohexane diisocyanate, isophorone diisocyanate (IPDI), and 4,4'- dicyclohexylmethane diisocyanate (H12MDI); and combinations thereof, but is not limited thereto.

In an exemplary embodiment of the present specification, the isocyanate-based curing agent includes at least one of an aliphatic cyclic isocyanate compound and an aliphatic acyclic isocyanate compound.

In an exemplary embodiment of the present specification, the pressure-sensitive adhesive composition may be used by mixing two or more isocyanate-based curing agents, and the ratio may be appropriately selected and used.

In one embodiment of the present specification, the pressure-sensitive adhesive composition further comprises a solvent. As the solvent, a known appropriate solvent, for example, a ketone-based solvent, an acetate-based solvent, or a toluene-based solvent may be used, but is not limited thereto.

In one embodiment of the present specification, the pressure-sensitive adhesive composition further comprises a catalyst. The catalyst may be appropriately selected in consideration of the purpose of the present application, and, for example, may be included in an amount of 10 ppm to 500 ppm compared to the urethane polymer.

As the catalyst, a tin-based catalyst such as DBTDL (dibutyl tin dilaurate), a lead-based catalyst, salts of organic and inorganic acids, an organometallic derivative, an amine-based catalyst, a diazabicycloundecene-based catalyst, etc. may be used, but is not limited thereto.

In an exemplary embodiment of the present specification, the pressure-sensitive adhesive composition may further include a curing retardant. As the curing retardant, any suitable known material may be used, and the content of the curing retardant may be appropriately selected. In one embodiment, acetyl acetone may be used as the curing retardant.

In one embodiment of the present specification, the pressure-sensitive adhesive composition may further include various general additives.

In an exemplary embodiment of the present specification, the acrylic polymer is 1 part by weight or more based on 100 parts by weight of the urethane polymer; 3 parts by weight or more; or 5 parts by weight or more.

In an exemplary embodiment of the present specification, the acrylic polymer is 15 parts by weight or less relative to 100 parts by weight of the urethane polymer; or 12 parts by weight or less.

When the acrylic polymer is included in less than the above range, the effect of reducing the adhesive force of the pressure-sensitive adhesive layer may be insufficient, and when included in the above range, haze of the pressure-sensitive adhesive layer may be caused.

In one embodiment of the present specification, the curing agent is 1 part by weight or more based on 100 parts by weight of the urethane polymer; 5 parts by weight or more; or 10 parts by weight or more.

In an exemplary embodiment of the present specification, the curing agent is 25 parts by weight or less relative to 100 parts by weight of the urethane polymer; or 20 parts by weight or less.

When the curing agent is included in excess of the above range, there is a problem in that an isocyanate group remains in the formed pressure-sensitive adhesive layer, thereby increasing adhesive strength. have.

The present specification also provides a pressure-sensitive adhesive layer comprising an acrylic polymer,

The acrylic polymer provides a pressure-sensitive adhesive layer comprising, as a monomer unit, a (meth)acrylate monomer including an alkyl group having 8 or more carbon atoms.

For the acrylic polymer included in the pressure-sensitive adhesive layer, the same content as the acrylic polymer included in the pressure-sensitive adhesive composition may be applied.

In an exemplary embodiment of the present specification, the pressure-sensitive adhesive layer further includes a cured product of a urethane polymer and a curing agent. Here, the same content for the urethane polymer and the curing agent included in the pressure-sensitive adhesive composition may be applied to the urethane polymer and the curing agent.

In an exemplary embodiment, the curing agent is an isocyanate-based curing agent, and the cured product of the urethane polymer and the curing agent may refer to a material formed by reacting the OH group of the urethane polymer and the NCO group of the curing agent.

An exemplary embodiment of the present specification includes a base film and a base layer comprising a first antistatic layer and a second antistatic layer respectively provided on both surfaces of the base film; and

As a surface protection film comprising a pressure-sensitive adhesive layer provided on the opposite side of the surface on which the base film of the second antistatic layer is provided,

The pressure-sensitive adhesive layer includes an acrylic polymer,

The acrylic polymer provides a surface protection film comprising, as a monomer unit, a (meth)acrylate monomer including an alkyl group having 8 or more carbon atoms.

An exemplary embodiment of the present specification includes a base film and a base layer comprising a first antistatic layer and a second antistatic layer respectively provided on both surfaces of the base film; and

As a surface protection film comprising a pressure-sensitive adhesive layer provided on the opposite side of the surface on which the base film of the second antistatic layer is provided,

The pressure-sensitive adhesive layer provides a surface protection film comprising a cured product of the above-described pressure-sensitive adhesive composition.

In an exemplary embodiment of the present specification, the surface protection film is a protective film, a third antistatic layer and a fourth antistatic layer provided on both surfaces of the protective film, respectively, and a surface of the third antistatic layer on which the protective film is provided. Further comprising a protective layer comprising a release layer provided on the opposite surface,

The protective layer may be provided such that the release layer faces the pressure-sensitive adhesive layer.

1 is a cross-sectional view of a surface protection film according to an exemplary embodiment of the present invention. The surface protection film shown in FIG. 1 includes a first antistatic layer 11A, a base film 111, a second antistatic layer 11B, an adhesive layer 124, a release layer 123, and a third antistatic layer 11C. , a protective film 131 and a fourth antistatic layer 11D are sequentially provided.

In an exemplary embodiment, the surface protection film is a surface protection film for protecting the surface of an organic light emitting device during an organic light emitting electronic device manufacturing process.

The pressure-sensitive adhesive layer of the present invention according to an exemplary embodiment may be provided on one surface of the second antistatic layer, thereby reducing the amount of accumulated static electricity. In addition, since the surface resistance of the pressure-sensitive adhesive layer is reduced, the generation of static electricity on the surface of the pressure-sensitive adhesive layer may be reduced when the protective layer is peeled off from the surface protection film.

Therefore, when removing the protective layer from the surface protection film in order to attach the pressure-sensitive adhesive layer to the surface of the adherend or peeling the surface protection film from the surface of the adherend, foreign substances that may be attached to the pressure-sensitive adhesive layer or the adherend by static electricity are prevented. can do. In addition, it is possible to prevent deterioration of the properties of the adherend surface by preventing contamination of the adherend surface during the process.

In one embodiment, the surface protection film may be used by removing the protective layer from the surface protection film and attaching the pressure-sensitive adhesive layer to the surface of the device to protect the surface. FIG. 2 illustrates a state in which the protective layer is removed from the surface protection film of FIG. 1 .

Referring to FIG. 2 , the surface protection film from which the protective layer is removed includes a first antistatic layer 11A, a base film 111 , a second antistatic layer 11B, and an adhesive layer 124 in order.

FIG. 3 shows a form in which the surface protection film of FIG. 2 is attached to the surface of the adherend 140 in order to protect the surface of the adherend.

In the present specification, the adherend means a material to which the pressure-sensitive adhesive layer can be adhered. In an exemplary embodiment, the adherend includes, but is not limited to, an encapsulation layer of an organic light emitting device and a plastic substrate applied to the device.

The type of the base film is not particularly limited. The base film is, for example, a polyethylene terephthalate film, a polytetrafluoroethylene film, a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a vinyl chloride copolymer film, a polyurethane film, an ethylene-vinyl acetate film , an ethylene-propylene copolymer film, an ethylene-ethyl acrylate copolymer film, an ethylene-methyl acrylate copolymer film, or a polyimide film, but is not limited thereto. In an exemplary embodiment of the present invention, the base film may be a polyethylene terephthalate (PET) film.

The thickness of the base film may be appropriately selected in consideration of the purpose of the present application. For example, the thickness of the base film is 25 μm or more and 150 μm or less; 50 µm or more and 125 µm or less; Alternatively, it may be 50 μm or more and 100 μm or less. When the surface protection film is laminated to the encapsulation layer of the organic light emitting device, if the range of the base film is less than the above thickness range, there is a risk that deformation of the base film may easily occur, and when the range of the base film exceeds the above thickness range, poor bonding occurs. can occur

The base film may be subjected to an appropriate adhesion treatment such as, for example, corona discharge treatment, ultraviolet irradiation treatment, plasma treatment, or sputter etching treatment, but is not limited thereto.

In an exemplary embodiment, the base film may be directly attached to the first and/or second antistatic layer. In another embodiment, when the surface treatment is performed on the base film, the first and/or second antistatic layer may be attached to the surface-treated base film.

As used herein, the term 'antistatic layer' means a layer for the purpose of suppressing the generation of static electricity.

The first to fourth antistatic layers may be formed by a known method in order to achieve a desired effect. For example, the first to fourth antistatic layers may be formed on both surfaces of the base film and the protective film by an in-line coating method.

In the present invention, the first to fourth antistatic layers may be formed of an appropriate antistatic composition in consideration of the purpose of the present application. For example, the first to fourth antistatic layers are selected from the group consisting of acrylic resins, urethane resins, urethane-acrylic copolymers, ester resins, ether resins, amide resins, epoxy resins, and melamine resins, or It may include a mixture thereof, but is not limited thereto.

In one example, the first to fourth antistatic layers may include a conductive material. The conductive material may include, but is not limited to, a conductive polymer or carbon nanotubes.

The conductive polymer may be composed of, for example, polyaniline, polypyrrole, polythiophene series, derivatives and copolymers thereof, but is not limited thereto.

The carbon nanotube may have a tube shape formed by rolling a graphite plate shape formed by connecting hexagonal rings made of 6 carbons to each other. Since the carbon nanotube has excellent rigidity and electrical conductivity, when used as an antistatic layer of a surface protection film, the hardness of the antistatic layer may increase and an antistatic function may be improved.

The thickness of the first to fourth antistatic layers may be appropriately selected in consideration of the purpose of the present application, and the thickness of each antistatic layer may be the same as or different from each other.

In an exemplary embodiment, the first to fourth antistatic layers may each independently have a thickness of 10 nm or more and less than 400 nm, preferably 20 nm or more and 300 nm or less; Or 20 nm or more and 100 nm or less. Since the first to fourth antistatic layers have a thickness within the above-described range, it is possible to have excellent coating properties on both surfaces of the base film or both surfaces of the protective film.

In an exemplary embodiment, the surface resistance of the first to fourth antistatic layers may be appropriately selected in consideration of the purpose of the present application. For example, the surface resistances of the first to fourth antistatic layers are each independently 10 ⁴ Ω/sq or more; 10 ⁵ Ω/sq or more; 10 ⁶ Ω/sq or more; 10 ⁷ Ω/sq or more; 10 ⁸ Ω/sq or more; or 10 ⁹ Ω/sq or more. For example, the surface resistances of the first to fourth antistatic layers are each independently 5×10 ¹² Ω/sq or less; or 10 ¹¹ Ω/sq or less. When the first to fourth antistatic layers have a surface resistance within the above-described range, the surface protection film may have an excellent antistatic function.

In one embodiment, the first and second antistatic layers are in direct contact with both surfaces of the base film, respectively. In one embodiment, the third and fourth antistatic layers are in direct contact with both surfaces of the protective film, respectively.

In the present invention, the thickness of the pressure-sensitive adhesive layer may be appropriately selected in consideration of the purpose of the present application. For example, the thickness of the pressure-sensitive adhesive layer is 10㎛ or more; 30 μm or more; Or it may be 45 μm or more. For example, the thickness of the pressure-sensitive adhesive layer is 200㎛ or less; 150 μm or less; 100 μm or less; or 90 μm or less.

By making the thickness of the pressure-sensitive adhesive layer within the above range, the adhesiveness and wetting properties of the pressure-sensitive adhesive layer to the surface of the adherend may be improved.

In the present invention, the protective layer is a protective film; and a third antistatic layer and a fourth antistatic layer respectively provided on both surfaces of the protective film. A release layer is provided on a surface opposite to the surface on which the protective film is provided of the third antistatic layer.

The protective film may include, for example, polyethylene terephthalate; polytetrafluoroethylene; polyethylene; polypropylene; polybutene; polybutadiene; vinyl chloride copolymer; Polyurethane; ethylene-vinyl acetate; ethylene-propylene copolymers; ethylene-ethyl acrylate copolymer; ethylene-methyl acrylate copolymer; polyimide; nylon; styrenic resin or elastomer; polyolefin-based resins or elastomers; other elastomers; polyoxyalkylene-based resins or elastomers; polyester-based resins or elastomers; polyvinyl chloride-based resin or elastomer; polycarbonate-based resins or elastomers; polyphenylene sulfide-based resin or elastomer; mixtures of hydrocarbons; polyamide-based resins or elastomers; acrylate-based resins or elastomers; epoxy-based resins or elastomers; silicone-based resins or elastomers; And it may include one or more selected from the group consisting of a liquid crystal polymer, but is not limited thereto.

The thickness of the protective film may be appropriately selected in consideration of the purpose of the present application. For example, 25 µm or more and 150 µm or less; 25 μm or more and 125 μm or less; Alternatively, it may be 25 μm or more and 100 μm or less. When the thickness of the protective film is less than the above range, there is a risk that the protective film is easily deformed when the surface protection film having the pressure-sensitive adhesive layer formed on the encapsulation layer of the organic light-emitting device is bonded to each other. can occur

The material of the release layer may be appropriately selected according to the purpose of the present invention. The material of the release layer may include, for example, a silicone-based release agent, a fluorine-based release agent, a long-chain alkyl-based release agent, a fatty acid amide-based release material, and the like, but is not limited thereto. In one embodiment, a silicone-based release agent may be used as the material of the release layer.

As the silicone-based mold release agent, for example, an addition-reaction silicone polymer can be used.

The release layer may be formed by applying the release layer material to, for example, a protective layer and drying. Any suitable coating method may be suitably used as a method for coating and drying the release layer material.

The thickness of the release layer may be appropriately selected in consideration of the purpose of the present application. For example, the thickness of the release layer is 10 nm or more and 500 nm or less; 10 nm or more and 300 nm or less; Alternatively, it may be 10 nm or more and 200 nm or less. If the release layer does not have the above-described thickness, the film may be defective during the process, so it is preferable to have the above thickness.

In the present specification, unless otherwise specified, the term 'glass' may mean alkali-free glass (NEG, OA-21).

In the surface protection film according to an exemplary embodiment of the present specification, peeling when the pressure-sensitive adhesive layer is peeled from the glass opposite to the side provided with the base layer at a peeling rate of 1.8 m/min and a peeling angle of 180° The force is 0.5 gf/in or more and 10 gf/in or less.

In the surface protection film according to an exemplary embodiment of the present specification, peeling when the pressure-sensitive adhesive layer is peeled from the glass opposite to the side provided with the base layer at a peeling rate of 1.8 m/min and a peeling angle of 180° force less than 10 gf/in; 8 gf/in or less; or 5 gf/in or less.

In one embodiment, the peeling force when peeling the opposite side of the surface with the base layer of the pressure-sensitive adhesive layer from the glass at a peeling rate of 1.8m/min and a peeling angle of 180° is the width of the surface protection film After cutting to be 25 mm and 150 mm in length, the adhesive layer of the surface protection film was attached to the glass with a 2 kg roller, and stored for 24 hours at a temperature of 25° C. and 50% relative humidity, followed by a material property analyzer ( Peeling force when peeling the surface protection film from the glass at a peeling rate of 1.8 m/min and a peeling angle of 180° using Texture Analyzer (manufactured by Stable Microsystems, UK).

In an exemplary embodiment, the peel force when peeling the surface protection film from the glass at a peeling rate of 1.8 m/min and a peeling angle of 180° is a value measured under a temperature of 25° C. and a relative humidity of 50% .

In the surface protection film according to an exemplary embodiment of the present specification, the residual ratio of the surface opposite to the surface provided with the base layer of the pressure-sensitive adhesive layer is 80% or more; 81% or more; 82% or more; or 83% or more.

In the surface protection film according to an exemplary embodiment of the present specification, the residual ratio of the surface opposite to the surface on which the base layer of the pressure-sensitive adhesive layer is provided is 100% or less. The residual ratio of 100% means that there is no residual amount of the pressure-sensitive adhesive layer.

In an exemplary embodiment of the present specification, the residual rate of the pressure-sensitive adhesive layer on the opposite side of the surface provided with the base layer is the peeling force when peeling from the glass at a peeling rate of 1.8m/min and a peeling angle of 180° It can be obtained by preparing an adhesive (Ref.) of 1,800±100 gf/in, measuring the adhesive strength (A) and (B) as follows, and calculating the formula of the following formula (4),

The adhesive force (B) is obtained by attaching the pressure-sensitive adhesive layer of the surface protection film to the glass and storing it for 10 days at a temperature of 60° C. and a relative humidity of 90%, then removing the surface protection film from the glass, and the surface Peeling force when the adhesive (Ref.) is attached to the glass surface from which the protective film has been removed, and the adhesive (Ref.) is peeled from the glass at a peeling rate of 1.8m/min and a peeling angle of 180° ,

The adhesive force (A) is the peeling force when the adhesive (Ref.) is peeled from the glass at a peeling rate of 1.8 m/min and a peeling angle of 180°.

[Formula 4]

Residual rate (%) = (Adhesive force (B)/Adhesive force (A))×100

In one embodiment, as an adhesive (Ref.) having a peeling force of 1,800±100 gf/in when peeling from glass at a peeling speed of 1.8 m/min and a peeling angle of 180°, LG Chem's 9002D product, etc. can be used. However, the present invention is not limited thereto.

In one embodiment, the peel force when peeling the pressure-sensitive adhesive (Ref.) from the glass at a peel rate of 1.8 m/min and a peel angle of 180° is measured under a temperature of 25° C. and a relative humidity of 50%. is the value

Another exemplary embodiment of the present specification provides a method of manufacturing a surface protection film. The said manufacturing method relates to the manufacturing method of the above-mentioned surface protection film, for example. Accordingly, the above-described surface protection film may be equally applied to the surface protection film formed by the method for manufacturing the surface protection film to be described later.

In one example, the method for manufacturing the surface protection film includes: forming a base film and a base layer including a first antistatic layer and a second antistatic layer respectively provided on both surfaces of the base film; A protective film, a third antistatic layer and a fourth antistatic layer respectively provided on both sides of the protective film, and a protective layer comprising a release layer provided on the opposite side of the third antistatic layer to the surface on which the protective film is provided to do; and bonding the base layer and the protective layer to the second antistatic layer and the release layer by using an adhesive layer to face each other.

In one embodiment, the method for manufacturing the surface protection film includes forming a pressure-sensitive adhesive layer on one surface of the second antistatic layer of the base layer before bonding the base layer and the protective layer by the pressure-sensitive adhesive layer. may include more. In this case, the step of bonding the base layer and the protective layer may be a step of bonding the base layer and the protective layer so that the pressure-sensitive adhesive layer and the release layer face each other.

Forming the pressure-sensitive adhesive layer on one surface of the second antistatic layer of the base layer may include coating the pressure-sensitive adhesive composition on the opposite surface of the second antistatic layer of the second antistatic layer to the opposite surface of the base film; and curing the coated pressure-sensitive adhesive composition.

As a method of coating the pressure-sensitive adhesive composition, a known coating method such as a reverse coating method, a gravure coating method, a spin coating method, a screen coating method, a fountain coating method, a dipping method, and a spray method may be used, but is not limited thereto.

Curing of the coated pressure-sensitive adhesive composition may be performed at an appropriate temperature and time. In one embodiment, curing of the coated pressure-sensitive adhesive composition may be made through aging in an oven at 40° C. for 3 days or more, but is not limited thereto.

In one embodiment, a base film, and a base layer comprising a first antistatic layer and a second antistatic layer respectively provided on both sides of the base film; And a surface protection film comprising an adhesive layer provided on the opposite side of the surface on which the base film of the second antistatic layer is provided may be prepared by peeling the protective layer from the surface protection film including the above-described protective layer and release layer. have.

An exemplary embodiment of the present specification provides a method of manufacturing an organic light emitting electronic device.

In an exemplary embodiment of the present specification, the method for manufacturing an organic light emitting electronic device includes attaching the pressure-sensitive adhesive layer of the above-described surface protection film on the encapsulation layer of the organic light emitting device.

In one embodiment, when the surface protection film further includes a protective layer, the method for manufacturing an organic light emitting electronic device includes removing the protective layer from the surface protection film before attaching the pressure-sensitive adhesive layer on the encapsulation layer. further comprising steps.

In the exemplary embodiment of the present specification, the organic light emitting device includes a back plate, a plastic substrate, a thin film transistor, an organic light emitting diode, and an encapsulation layer in sequence.

4 is a view illustrating a state in which a surface protection film according to an embodiment of the present invention is attached on an encapsulation layer during a manufacturing process of an organic light emitting electronic device. Referring to FIG. 4 , the surface protection film of FIG. 2 according to an exemplary embodiment of the present invention includes a back plate 511 , a plastic substrate 512 , a thin film transistor 513 , an organic light emitting diode 514 , and an encapsulation layer 515 . .

The encapsulation layer may exhibit excellent moisture blocking properties and optical properties in an organic light emitting electronic device. In addition, the encapsulation layer may be formed as a stable encapsulation layer irrespective of a shape of an organic light emitting electronic device such as top emission or bottom emission.

In an exemplary embodiment, the encapsulation layer may include a single or multi-layered inorganic material layer. As a method of forming the encapsulation layer, a method of forming an encapsulation layer known in the art may be applied.

The single-layer or multi-layer inorganic material layer may include, for example, an aluminum oxide-based material, a silicon-nitrogen compound-based material (Silicone nitride)-based material, or a silicon oxynitride-based material.

The manufacturing method of the organic light emitting electronic device of the present application includes the steps of: peeling the surface protection film from the encapsulation layer; and laminating a touch screen panel and a cover window on the encapsulation layer. Since the surface protection film exhibits an excellent antistatic function in the encapsulation layer when peeled from the encapsulation layer, when the touch screen panel is bonded on the encapsulation layer, foreign substances are prevented from adhering between the encapsulation layer and the touch screen, thereby preventing device defects can be prevented

Hereinafter, the present application will be described in more detail through Examples according to the present application and Comparative Examples not according to the present application, but the scope of the present application is not limited by the Examples presented below.

Preparation Example 1 - Preparation of pressure-sensitive adhesive composition 1

<Production of urethane polymer>

80 parts by weight of trifunctional preminol (polyether polyol, S 4013F, ASAHI GLASS CO. LTD., Mn=12,000 g/mol), bifunctional polyol (polypropylene glycol, PPG-1000d, Kumho Petrochemical, Mn=1,000g/mol) 5 parts by weight and a trifunctional MPD/TMPT-based polyol (a mixture of MPD (3-methyl-1,5-pentanediol) and TMPT (trimethylol propane adipate), Polyol F-3010, Kuraray, Mn = 3,000 g/mol) 15 parts by weight and ethyl acetate were added, and the mixture was stirred at high speed for 15 minutes under a catalyst (DBTDL). Next, 18 parts by weight of a polyfunctional alicyclic isocyanate compound (MHG-80B, ASAHI KASEI) was slowly added dropwise to 18 parts by weight of the preminol, polyol, and MPD/TMPT-based polyol relative to 100 parts by weight of the polyol. A urethane polymer having a weight average molecular weight of 110,000 g/mol was prepared by reacting until the (NCO) peak disappeared.

<Production of acrylic polymer (D1)>

A monomer mixture composed of 95 parts by weight of butyl methacrylate (BMA) and 5 parts by weight of stearyl methacrylate (STMA) was added to a 1L reactor in which nitrogen gas was refluxed and a cooling device was installed to facilitate temperature control, and then ethyl as a solvent Acetate was added. Then, after nitrogen gas was purged for about 1 hour to remove oxygen, the reactor temperature was maintained at 62°C. After making the mixture uniform, 400 ppm of azobisisobutylnitrile (AIBN) as a reaction initiator and 400 ppm of n-dodecylmercaptan (n-DDM) as a chain transfer agent were added, and the mixture was reacted. After the reaction, it was diluted with toluene to prepare an acrylic polymer (D1) having a weight average molecular weight of 30,000 g/mol.

<Preparation of adhesive composition 1>

100 parts by weight of the prepared urethane polymer, 100 parts by weight of the urethane polymer, 15 parts by weight of an HDI trimer-based curing agent (TKA-100, ASAHI KASEI), 7.5 parts by weight of the acrylic polymer, 0.005 parts by weight of the catalyst (DBTDL), and curing delay 3 parts by weight of the agent (acetyl acetone) was mixed, a toluene solvent was added so that the solid content concentration was 48wt%, and the mixture was stirred with a disper to prepare a pressure-sensitive adhesive composition 1.

Preparation Example 2 - Preparation of pressure-sensitive adhesive composition 2

An acrylic polymer (D2) having a weight average molecular weight of 30,000 g/mol was prepared in the same manner as in the preparation method of the acrylic polymer (D1) except that BMA/STMA was used in a weight ratio of 90:10.

A pressure-sensitive adhesive composition 2 was prepared in the same manner as in the pressure-sensitive adhesive composition 1, except that the acrylic polymer (D2) was used instead of the acrylic polymer (D1).

Preparation Example 3 - Preparation of pressure-sensitive adhesive composition 3

An acrylic polymer (D3) having a weight average molecular weight of 29,000 g/mol was prepared in the same manner as in the preparation method of the acrylic polymer (D1) except that BMA/STMA was used in a weight ratio of 85:15.

A pressure-sensitive adhesive composition 3 was prepared in the same manner as in the method for preparing the pressure-sensitive adhesive composition 1, except that the acrylic polymer (D3) was used in an amount of 10 parts by weight based on 100 parts by weight of the urethane polymer instead of the acrylic polymer (D1).

Preparation Example 4 - Preparation of pressure-sensitive adhesive composition 4

An acrylic polymer (D4) having a weight average molecular weight of 30,000 g/mol was prepared in the same manner as in the preparation of the acrylic polymer (D1) except that BMA/STMA was used in a weight ratio of 80:20.

A pressure-sensitive adhesive composition 4 was prepared in the same manner as in the method for preparing the pressure-sensitive adhesive composition 1, except that the acrylic polymer (D4) was used instead of the acrylic polymer (D1).

Preparation Example 5 - Preparation of pressure-sensitive adhesive composition 5

An acrylic polymer (D5) having a weight average molecular weight of 31,000 g/mol was prepared in the same manner as in the preparation of the acrylic polymer (D1) except that BMA/STMA was used in a weight ratio of 70:30.

A pressure-sensitive adhesive composition 5 was prepared in the same manner as in the method for preparing the pressure-sensitive adhesive composition 1, except that the acrylic polymer (D5) was used in an amount of 10 parts by weight based on 100 parts by weight of the urethane polymer instead of the acrylic polymer (D1).

Comparative Preparation Example 1 - Preparation of Comparative Composition 1

Comparative composition 1 was prepared in the same manner as in the preparation method of pressure-sensitive adhesive composition 1, except that the acrylic polymer (D1) was not used.

Comparative Preparation Example 2- Preparation of Comparative Composition 2

Comparative composition 2 was prepared in the same manner as in the preparation method of pressure-sensitive adhesive composition 1, except that isopropyl myristate (IPMS) was used in an amount of 20 parts by weight based on 100 parts by weight of the urethane polymer instead of the acrylic polymer (D1).

Comparative Preparation Example 3 - Preparation of Comparative Composition 3

Comparative composition 3 was prepared in the same manner as in the preparation method of the pressure-sensitive adhesive composition 1, except that isopropyl myristate (IPMS) was used in an amount of 40 parts by weight based on 100 parts by weight of the urethane polymer instead of the acrylic polymer (D1).

Preparation of surface protection film

As the base layer, a 75 μm thick polyethylene terephthalate (PET) film (H330, Kolon Co.) in which an antistatic layer of 50 nm was coated on both sides of the base film was prepared. As a protective layer, an antistatic layer is formed on both sides of a 50 μm thick polyethylene terephthalate (PET) film (XD510P, TAK), and a film (12ASW, SKC) coated with a release layer on one antistatic layer is prepared. did Next, after comma-coating the pressure-sensitive adhesive composition on one surface of the base layer to a thickness of 75 μm and drying with hot air, the protective layer is laminated on the pressure-sensitive adhesive composition so that the base layer and the release layer face each other and aged at 40° C. for 5 days. After that, a surface protection film was prepared.

The surface protection films of Examples 1 to 5 and Comparative Examples 1 to 3 were prepared in the same manner as in the preparation method of the surface protection film, except that the pressure sensitive adhesive composition was used as the pressure sensitive adhesive compositions 1 to 5 and Comparative Compositions 1 to 3. Table 1 below briefly compares the configurations of Examples 1 to 5 and Comparative Examples 1 to 3.

The physical properties of the pressure-sensitive adhesive layer in Examples and Comparative Examples of the present application were evaluated in the following manner, and the results are shown in Table 2 below.

Measurement of peel force

The surface protection films of Examples 1 to 5 and Comparative Examples 1 to 3 were cut to have a width of 25 mm and a length of 150 mm. Then, the pressure-sensitive adhesive layer of the surface protection film is attached to the glass using a 2 kg roller, and stored at room temperature for about 24 hours. Then, using equipment (Texture Analyzer, Stable Microsystems Co., Ltd., UK), the low-speed peeling force was evaluated while peeling the base film on which the pressure-sensitive adhesive layer was formed from the glass at a peeling rate of 1.8m/min and a peeling angle of 180°. . After the peel force was measured for two identical specimens, the average value was adopted.

Residue measurement

Prepare an adhesive (Ref.) having a peeling force of 1800±100 gf/in when peeling from glass at a peeling rate of 1.8m/min and a peeling angle of 180°.

Measurement of Adhesive Force (B): After attaching the adhesive layer of the prepared surface protection film to glass and storing it for 10 days at a temperature of 60° C. and a relative humidity of 90%, the surface protection film is removed from the glass. The adhesive (Ref.) was attached to the glass surface from which the surface protection film was removed, and peeling force was evaluated while peeling at a peeling rate of 1.8m/min and a peeling angle of 180°. Let this be adhesive force (B).

Measurement of adhesive force (A): the adhesive (Ref.) was attached to the glass, and the peel force when the adhesive (Ref.) was peeled from the glass at a peeling rate of 1.8 m/min and a peeling angle of 180° evaluated. Let this be adhesive force (A).

The adhesive force (A) and (B) were substituted into the following formula, and the residual ratio was obtained.

Residual rate (%) = (Adhesive force (B)/Adhesive force (A))×100

acrylic polymer
Molecular Weight (g/mol) of BMA/STMA
weight ratio Acrylic polymer content (mid section) plasticizer type
(parts by weight) Example 1 30,000 95:5 7.5 - Example 2 30,000 90:10 7.5 - Example 3 29,000 85:15 10 - Example 4 30,000 80:20 7.5 - Example 5 3.1 million 70:30 10 - Comparative Example 1 - - - - Comparative Example 2 - - - IPMS(20) Comparative Example 3 - - - IPMS(40)

Peel force (gf/in) Residual rate (%) Example 1 4.6 92 Example 2 3.7 90 Example 3 2.5 87 Example 4 2.5 85 Example 5 1.9 83 Comparative Example 1 14 92 Comparative Example 2 6.2 78 Comparative Example 3 4.3 68

From Table 2 above, when the surface protection film of the present invention is used, the adhesive strength between the pressure-sensitive adhesive layer and the adherend is low, so that the film can be peeled with a low peeling force, and the residue from the pressure-sensitive adhesive layer after peeling is small, indicating that the surface of the adherend is less contaminated. can be checked

11A: first antistatic layer
11B: second antistatic layer
11C: third antistatic layer
11D: fourth antistatic layer
110: base layer
111: base film
123: release layer
124: adhesive layer
130: protective layer
131: protective film
140: adherend
510: organic light emitting device
511: back plate
512: plastic substrate
513: thin film transistor
514: organic light emitting diode
515: encapsulation layer

Claims (16)

urethane polymers; acrylic polymer; and a curing agent;
The acrylic polymer comprises a (meth)acrylate monomer including an alkyl group having 8 or more carbon atoms as a monomer unit,
The (meth)acrylate monomer comprising an alkyl group having 8 or more carbon atoms is included in an amount of 1 wt% to 40 wt% based on the total amount of monomer units included in the acrylic polymer. delete The pressure-sensitive adhesive composition according to claim 1, wherein the acrylic polymer further comprises an alkyl (meth)acrylate monomer having less than 8 carbon atoms in an amount of 60% to 99% by weight based on the total amount of monomer units included in the acrylic polymer. The pressure-sensitive adhesive composition of claim 1, wherein the acrylic polymer has a weight average molecular weight of 10,000 g/mol to 60,000 g/mol. The pressure-sensitive adhesive composition of claim 1, wherein the urethane polymer has a weight average molecular weight of 60,000 g/mol to 160,000 g/mol. The pressure-sensitive adhesive composition according to claim 1, wherein the acrylic polymer is included in an amount of 1 to 15 parts by weight based on 100 parts by weight of the urethane polymer. The pressure-sensitive adhesive composition of claim 1, wherein the curing agent is included in an amount of 1 to 25 parts by weight based on 100 parts by weight of the urethane polymer. As a pressure-sensitive adhesive layer comprising an acrylic polymer,
The acrylic polymer comprises a (meth)acrylate monomer including an alkyl group having 8 or more carbon atoms as a monomer unit,
The (meth)acrylate monomer comprising an alkyl group having 8 or more carbon atoms is included in an amount of 1 wt% to 40 wt% based on the total amount of monomer units included in the acrylic polymer,
The pressure-sensitive adhesive layer further comprises a cured product of a urethane polymer and a curing agent. delete a base film and a base layer comprising a first antistatic layer and a second antistatic layer respectively provided on both surfaces of the base film; and
As a surface protection film comprising a pressure-sensitive adhesive layer provided on the opposite side of the surface on which the base film of the second antistatic layer is provided,
The pressure-sensitive adhesive layer is a surface protection film of the pressure-sensitive adhesive layer according to claim 8. The method according to claim 10, comprising a protective film, a third antistatic layer and a fourth antistatic layer provided on both sides of the protective film, respectively, and a release layer provided on a surface opposite to the surface on which the protective film of the third antistatic layer is provided further comprising a protective layer that
The protective layer is a surface protection film in which the release layer is provided to face the pressure-sensitive adhesive layer. The method according to claim 10, wherein the peeling force when peeling the opposite side of the surface with the base layer of the pressure-sensitive adhesive layer from the glass at a peeling rate of 1.8m/min and a peeling angle of 180° is 0.5gf/in or more and 10gf/in in or less surface protection film. The surface protection film according to claim 10, wherein a residual ratio of the pressure-sensitive adhesive layer opposite to the surface on which the base layer is provided is 80% or more. A method of manufacturing an organic light emitting electronic device comprising the step of attaching the pressure-sensitive adhesive layer of the surface protection film according to claim 10 on an encapsulation layer of an organic light emitting device. The method of claim 14 , wherein the organic light emitting device sequentially includes a back plate, a plastic substrate, a thin film transistor, an organic light emitting diode, and an encapsulation layer. The method of claim 14, further comprising: peeling the surface protection film from the encapsulation layer; and laminating a touch screen panel and a cover window on the encapsulation layer.

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