KR20200012568A - Adhesive composition, adhesive film, laminate and preparation method thereof - Google Patents

Abstract

The present invention relates to an adhesive film which easily removes unnecessary parts by initially attaching a film to a substrate with low adhesion, and then strongly attaches the same to the substrate by easily increasing the adhesive strength of a remaining part of the film. In particular, the adhesive film of the present invention has excellent adhesive force variability because the final adhesive strength is sufficiently high while the initial adhesive strength is sufficiently low. Therefore, the adhesive film of the present invention and an adhesive composition for producing the same can be usefully applied in a process requiring adhesive variability, such as the production of an OLED display panel.

Description

Adhesive composition, adhesive film, laminated body and manufacturing method thereof {ADHESIVE COMPOSITION, ADHESIVE FILM, LAMINATE AND PREPARATION METHOD THEREOF}

The present invention relates to an adhesive composition, an adhesive film, a laminate and a method for producing the same. More specifically, the present invention relates to an adhesive film having a variable adhesive force, a method for preparing the same, a composition for preparing the same, and a laminate and an apparatus including the same.

Substrates used in display panels and the like generally require a tape for surface protection or bonding with other components from damage by external impact. For example, a tape for joining a component with a polyimide substrate is used in an organic light emitting diode (OLED) panel.

On the other hand, there is a region where a member of the tape is preferred for functional reasons on the display panel, and for example, it is preferable that the tape does not exist in regions where connection with other terminals is made. Particularly in the manufacturing process of a bending display panel which is recently attracting attention, a precise taping process is required since there should be no tape in the area where the panel is bent (see US Patent Publication No. 2011-0210937).

In such a process, the tape can be initially attached to the substrate with low adhesive force, so that unnecessary parts can be easily removed, and then the adhesive variable tape, which can be strongly attached to the substrate by easily increasing the adhesive strength of the rest of the tape, Required.

US Patent Publication No. 2011-0210937

Currently, adhesive films have been developed that incorporate various additives into the adhesive to realize adhesive force variability. However, these conventional adhesive variable films have poor compatibility between the adhesive and the additive, the initial adhesive strength is not low enough, or the final adhesive strength is not high enough. I have problems

Accordingly, an object of the present invention is to provide an adhesive film having a variable adhesive strength, a method for preparing the same, a composition for producing the same, and a laminate and a device including the same, which can solve the above problems and exhibit high performance.

According to one aspect of the invention, a base polymer; A crosslinking agent reacted with the base polymer; A first monomer polymerized after the reaction of the base polymer and the crosslinking agent; And an initiator for polymerizing the first monomer. The adhesive composition has a first adhesive force before the polymerization of the first monomer and a second adhesive force after the polymerization of the first monomer after the reaction of the base polymer and the crosslinking agent, and the second adhesive force is the first adhesive force. Higher than

According to another aspect of the present invention, there is provided an adhesive film comprising a reaction product of a base polymer and a crosslinking agent, wherein the adhesive film contains a first monomer and an initiator and the first monomer is polymerizable by the initiator, and the adhesive film Has a first adhesive force before the polymerization of the first monomer and a second adhesive force after the polymerization of the first monomer, wherein the second adhesive force is higher than the first adhesive force.

According to another aspect of the invention, there is provided a laminate comprising a substrate and the adhesive film.

According to another aspect of the present invention, an apparatus including the laminate is provided.

According to another aspect of the invention, the display panel; And the laminate attached to the display panel.

The adhesive film according to the present invention can be repositioned by initially attaching the film to the substrate with a low adhesive force, and can easily remove unnecessary portions, and then easily increase the adhesive force of the rest of the film to the substrate. Can be strongly attached.

In particular, the adhesive film of the present invention is excellent in miscibility between the constituents, the initial adhesive strength is sufficiently low while the final adhesive force is sufficiently high, and the adhesive force variability is very excellent.

Therefore, the adhesive film of the present invention and the adhesive composition for manufacturing the same may be usefully applied in a process requiring adhesive force variability such as the manufacture of a display panel such as an OLED.

1 is a graph showing a change in adhesion force according to the polymerization of the first monomer of the adhesive composition according to one embodiment.
2 is a graph showing a change in adhesion force according to the addition of the second monomer of the adhesive composition according to one embodiment.
3 is a graph showing a change in storage modulus of elasticity of a base polymer of an adhesive composition according to an embodiment when crosslinking.
4 illustrates a cross-sectional view of an adhesive tape including an adhesive film according to one embodiment.
5 shows an example of a method of manufacturing a laminate according to one embodiment.
6A and 6B show adhesion before and after UV curing, respectively, for the adhesive compositions 3A to 3F prepared in Example 3. FIG.

Advantages and features of the present invention, and methods of accomplishing the same will become apparent with reference to the examples described in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the examples disclosed below, but may be implemented in various different forms. That is, these examples are provided only to make the disclosure of the present invention complete, and to fully convey the scope of the invention to those skilled in the art, and the present invention is defined by the scope of the claims. It will be.

Shapes, sizes, ratios, angles, numbers, and the like disclosed in the drawings for describing the present invention are exemplary, and the present invention is not limited to the items shown in the drawings. Like reference numerals refer to like elements throughout. In addition, in describing the present invention, if it is determined that the detailed description of the related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

In the present specification, when 'comprises', 'haves', 'consists of', etc., other matters other than those described may be added unless the expression 'only' is used. When a component is expressed in the singular, it includes the case where a plural is included unless there is particular notice.

In interpreting the components, they should be construed to include the margin of error even if no explicit statement is made.

In the case of the description of the positional relationship, for example, if the positional relationship of the two parts is described as 'on', 'upper', 'lower', 'next to', etc. Alternatively, one or more other parts may be located between them where the expression 'direct' is not used.

Each of the features of the examples of the invention may be combined or combined with one another in whole or in part, and technically various interlocking and driving are possible.

Hereinafter, examples of the present invention will be described in detail with reference to the drawings. The following examples are provided as examples to fully convey the spirit of the present invention to those skilled in the art. Accordingly, the present invention is not limited to the examples described below and may be implemented in other forms.

Adhesive composition

According to one aspect of the invention, an adhesive composition is provided comprising a base polymer, a crosslinking agent, a first monomer and an initiator.

The base polymer may react with the crosslinking agent before the first monomer is polymerized by the initiator. For example, the base polymer may react with the crosslinking agent while the first monomer and the initiator are preserved. The adhesion of the adhesive composition after the reaction may be further improved after polymerization of the first monomer.

Adhesive composition according to one embodiment includes a base polymer; A crosslinking agent reacted with the base polymer; A first monomer polymerized after the reaction of the base polymer and the crosslinking agent; And an initiator for polymerizing the first monomer. The adhesive composition has a first adhesive force before the polymerization of the first monomer and a second adhesive force after the polymerization of the first monomer after the reaction of the base polymer and the crosslinking agent, and the second adhesive force is the first adhesive force. Higher than

The polymerization of the first monomer may be polymerized by a photoinitiator or a thermal initiator. Specifically, when the photoinitiator is included in the adhesive composition, the first monomer may be polymerized by the photoinitiator after UV irradiation, and when the thermal initiator is included in the adhesive composition, the first monomer is polymerized by the thermal initiator after heating. Can be.

Properties of Adhesive Composition

Hereinafter, the properties of the adhesive composition will be described with reference to the drawings.

The adhesive composition according to the embodiment includes a first monomer and has a structure different from that before the polymerization at the time of polymerization of the first monomer.

1 is a graph showing a change in adhesion force according to the polymerization of the first monomer of the adhesive composition according to an embodiment

As shown in FIG. 1, the adhesive composition has a low adhesive strength when the first monomer is added (eg, 30 gf / in or less), and then the adhesive force rapidly increases as the first monomer is polymerized (eg, 1 kgf). / in or greater)

Accordingly, the adhesive composition has a first adhesive force before the polymerization of the first monomer and the base polymer and a second adhesive force after the polymerization of the first monomer, and the second adhesive force is higher than the first adhesive force. .

In addition, the adhesive composition may further include a second monomer different from the first monomer, the complexity of the base polymer chain due to the action of the second monomer can be further improved the adhesion of the adhesive composition. .

2 is a graph showing a change in adhesion force according to the addition of the second monomer in the adhesive composition according to one embodiment.

As shown in FIG. 2, when the second monomer is added together, the adhesive force after the monomer polymerization is further increased as compared with the case where only the first monomer is added.

On the other hand, before the monomer polymerization, when the second monomer is added together when compared with the case where only the first monomer is added, it has a lower adhesive force, the improvement of the adhesive force may be more rapid by the second monomer.

Adhesion at Crosslinking of Base Polymer

In the adhesive composition, the base polymer may be reacted with (ie, crosslinked with) a crosslinking agent to form a film or the like, and the film thus formed has different characteristics from the conventional one in terms of physical properties such as adhesive strength.

Therefore, hereinafter, after the base polymer and the crosslinking agent are reacted, characteristics of the adhesive composition in the state where the first monomer and the initiator are preserved will be described.

The adhesive composition has a first adhesive force before the polymerization of the first monomer (ie, the state where the first monomer and the initiator are preserved).

The first adhesive force may be 200 gf / in or less, 150 gf / in or less, 100 gf / in or less, 50 gf / in or less, or 30 gf / in or less.

Specifically, the first adhesive force may range from 1 gf / in to 200 gf / in, 1 gf / in to 100 gf / in, or 1 gf / in to 30 gf / in.

In the present specification, the adhesive force (first adhesive force, second adhesive force, etc.) may be measured according to ASTM D3330, which is a general measuring method in the art, and may be, for example, adhesive force measured on polyimide. Examples of more detailed measurement methods have been described in detail in the Examples below.

The adhesive composition also has a second adhesive force after polymerization of the first monomer.

The second adhesive force may be 350 gf / in or more, 400 gf / in or more, 500 gf / in or more, or 1,000 gf / in or more.

Specifically, the second adhesive force may range from 350 gf / in to 3,000 gf / in, or from 500 gf / in to 2,000 gf / in.

As an example, the first adhesive force may be 200 gf / in or less, and the second adhesive force may be 350 gf / in or more.

As another example, the first adhesive force may be 150 gf / in or less, and the second adhesive force may be 400 gf / in or more.

As another example, the first adhesive force may range from 1 gf / in to 30 gf / in, and the second adhesive force may range from 500 gf / in to 2,000 gf / in.

In the adhesive composition, the second adhesive force is higher than the first adhesive force.

For example, the second adhesive force may be 150 gf / in or more, 200 gf / in or more, 500 gf / in or more, or 1000 gf / in or more than the first adhesive force.

In addition, the ratio of the second adhesive force to the first adhesive force may be 20 or more, 30 or more, 50 or more, 70 or more or 100 or more.

In addition, the ratio of the first adhesive force to the second adhesive force may be 0.06 or less, 0.03 or less, 0.02 or less, or 0.01 or less.

In addition, the base polymer may have an adhesive force between the first adhesive force and the second adhesive force.

When the adhesive composition further comprises a second monomer, the second adhesive force may be further improved.

That is, compared with the case where only the first monomer is added, when the second monomer is added together, the second adhesive force is further increased.

On the other hand, before the monomer polymerization, when the second monomer is added together compared to the case where only the first monomer is added, the first adhesive force may be lower.

Accordingly, the difference between the first adhesive force and the second adhesive force may be further increased by the second monomer.

That is, the first adhesive force and the second adhesive force may be adjusted by adjusting the addition amount of the first monomer and the second monomer.

Characteristics of the crosslinking of the base polymer

3 illustrates a change in storage modulus of crosslinking of a base polymer in an adhesive composition according to one embodiment. At this time, the storage modulus change of the general acrylic adhesive is shown together for comparison.

As shown in FIG. 3, the adhesive composition according to the embodiment maintains a storage modulus of 10 ⁶ dyne / cm ² or more even at a high temperature region of 100 ° C. or lower as the temperature increases and crosslinking of the base polymer proceeds. Therefore, it may be advantageous for high temperature processes such as a chip on plastic (COP) bonding process.

In the case of a typical acrylic type adhesive has a storage elastic modulus extremely lowered depending on the temperature rises, the cross-linking proceeds, the more than 100 ℃ 10 ⁵ dyne / cm ² to The storage modulus between 10 ⁶ dyne / cm ² was shown. In this case, the initial adhesiveness of the pressure-sensitive adhesive is improved, but it may not be suitable for the process of passing the high temperature region due to the low temperature durability and the flowability of the pressure-sensitive adhesive.

The adhesive composition may satisfy the requirement as an optically clear adhesive after polymerization of the first monomer.

For example, the adhesive composition may have a haze of 5% or less, 2% or less, or 1% or less after polymerization of the first monomer.

In addition, the adhesive composition may have a light transmittance of 80% or more, 90% or more, or 95% or more after polymerization of the first monomer.

In addition, the adhesive composition may satisfy the requirement as an optically clear adhesive even after the polymerization further comprises the second monomer.

For example, when the adhesive composition includes the first monomer and the second monomer, the haze after polymerization may be 5% or less or 2% or less.

When the adhesive composition includes the first monomer and the second monomer, light transmittance after polymerization may be 80% or more or 90% or more.

Components of the Adhesive Composition

The adhesive composition according to the embodiment includes a base polymer, a crosslinking agent, a first monomer and an initiator.

In addition, the adhesive composition according to the embodiment may further include a second monomer different from the first monomer.

In addition, the adhesive composition according to the embodiment may further include a solvent and other additives.

Hereinafter, each component of the adhesive composition will be described in detail.

Base polymer

Adhesive composition according to the embodiment comprises a base polymer.

The base polymer exhibits adhesive properties as a main component of the adhesive composition. In addition, the base polymer may be reacted with (ie, crosslinked with) a crosslinking agent to form a film or the like.

The base polymer may be included in the range of 35% to 95% by weight based on the weight of the adhesive composition. Specifically, the base polymer may be included in the range of 40% to 90%, 45% to 85%, or 50% to 80% by weight based on the weight of the adhesive composition. At this time, the content of the base polymer and the weight of the adhesive composition may be based on solids.

The base polymer may contain a functional group reactive with the crosslinking agent. For example, the base polymer may have one or more functional groups selected from the group consisting of carboxyl group, hydroxyl group, acryl group, methacryl group, acetate group and vinyl group.

As one example, the base polymer may be an acrylic resin.

Specifically, the base polymer may be an acrylic copolymer resin.

For example, the acrylic copolymer resin is 2-ethylhexyl acrylate (2-EHA), butyl acrylate (BA), methyl acrylate (MA), vinyl acetate (VAc), acrylic acid (AA) and 2-hydroxy At least two monomers selected from the group consisting of ethyl acrylate (2-HEA) may be a resin copolymerized.

As a specific example, the combination of at least two monomers constituting the acrylic copolymer resin is 2-EHA / MA, BA / MA, AA / 2-HEA, MA / 2-HEA, BA / 2-HEA, MA / AA / 2-HEA and the like.

The base polymer may be a thermosetting resin or a photocurable resin.

For example, the base polymer may be a thermosetting resin.

In addition, the base polymer may be a pressure-sensitive adhesive (PSA) resin.

The weight average molecular weight (Mw) of the base polymer may be 10,000 to 2,000,000. Alternatively, the weight average molecular weight of the base polymer may be 100,000 to 2,000,000.

First monomer

Adhesive composition according to the embodiment includes a first monomer.

The first monomer is for polymerization after the reaction of the base polymer and the crosslinking agent. That is, the first monomer may exist in an unpolymerized state even after the reaction of the base polymer and the crosslinking agent.

As such, the first monomer in an unpolymerized state may lower the adhesion between the reaction product of the base polymer and the crosslinking agent. However, the first monomer may be polymerized as necessary after the reaction of the base polymer and the crosslinking agent, thereby rapidly improving the adhesive force of the reaction product.

The content of the first monomer in the composition may be 10 parts by weight to 120 parts by weight based on 100 parts by weight of the base polymer. Specifically, the content in the composition of the first monomer may be 20 parts by weight to 110 parts by weight, 30 parts by weight to 100 parts by weight, or 40 parts by weight to 90 parts by weight based on 100 parts by weight of the base polymer. In this case, the content of the base polymer and the first monomer may be based on solid content.

The molecular weight of the first monomer may range from 50 to 2,000, or from 100 to 1,000.

As an example, the first monomer may be a monofunctional or bifunctional or higher compound, for example, a monofunctional to trifunctional compound. The first monomer may have at least one functional group selected from the group consisting of an acryl group, methacryl group, ethyleneoxy group, vinyl group and carboxyl group.

The first monomer may have compatibility with the base polymer. In addition, the first monomer may be polymerized by a photoinitiator or a thermal initiator.

As an example, the first monomer may be one or more compounds represented by the following Chemical Formula 1.

[Formula 1]

Wherein n is an integer from 1 to 5;

R ¹ is C _6-10 aryloxy unsubstituted or substituted with linear C _1-12 alkyl, or phenyl;

R ^a and R ^b are each independently hydrogen or acryloyloxymethyl.

According to an embodiment of Formula 1, n is an integer of 1 to 3.

According to another embodiment of Formula 1, n is an integer of 3 to 5.

According to another embodiment of Formula 1, R ¹ is linear C _1-3 alkyl.

According to another embodiment of Formula 1, R ¹ is linear C _6-12 alkyl.

According to another embodiment of Formula 1, R ¹ is phenyloxy.

According to another embodiment of Formula 1, R ¹ is phenyloxy substituted with phenyl.

According to another embodiment of Chemical Formula 1, R ^a and R ^b are hydrogen.

According to another embodiment of Formula 1, R ^a is hydrogen; R ^b is acryloyloxymethyl.

According to another embodiment of Chemical Formula 1, R ^a and R ^b are acryloyloxymethyl.

According to another embodiment of Formula 1, R ¹ is linear C _1-3 alkyl; R ^a and R ^b are acryloyloxymethyl.

According to another embodiment of Formula 1, R ¹ is linear C _6-12 alkyl; R ^a and R ^b are hydrogen.

According to another embodiment of Formula 1, R ¹ is phenyloxy; R ^a and R ^b are hydrogen.

According to another embodiment of Formula 1, R ¹ is phenyloxy substituted with phenyl; R ^a and R ^b are hydrogen.

More specific examples of the general formula (1) include trimethylolpropane triacrylate (TMPTA), lauryl acrylate, phenyl (EO) ₂ acrylate, o-phenylphenol EO acrylate and the like.

Initiator

Adhesive composition according to the embodiment comprises an initiator.

The initiator is for polymerizing the first monomer.

The initiator may be a photoinitiator or a thermal initiator.

The content in the composition of the initiator may be 0.1 to 10 parts by weight based on 100 parts by weight of the base polymer. Specifically, the content in the composition of the initiator may be 0.1 parts by weight to 5 parts by weight based on 100 parts by weight of the base polymer. In this case, the content of the initiator and the base polymer may be based on solid content.

Conventional photoinitiator can be used as the initiator, for example, 1 selected from the group consisting of ketones (benzophenone, acetophenone, etc.), benzoin, benzoin ether, benzyl and benzyl ketals as the photoinitiator. More than one species can be used.

As an example, the photoinitiator may be benzoin ethers (eg, benzoin methyl ether or benzoin isopropyl ether) or substituted benzoin ethers.

As another example, the photoinitiator may be substituted acetophenones such as 2,2-diethoxyacetophenone or 2,2-dimethoxy-2-phenylacetophenone.

As another example, the photoinitiator may be substituted alpha-ketones (eg 2-methyl-2-hydroxypropiophenone), aromatic sulfonylchlorides (eg 2-naphthalenesulfonylchloride), or Photoactive oximes (eg, 1-phenyl-1,2-propanedione-2- (O-ethoxycarbonyl) oxime).

As another example, the photoinitiator is 1-hydroxycyclohexylphenyl ketone, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 1- [4- (2-hydroxyethoxy) phenyl]- 2-hydroxy-2-methyl-1-propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone, 2-methyl-1- [4- (methyl Thio) phenyl] -2-morpholinopropane-1-one, 2-hydroxy-2-methyl-1-phenyl propane-1-one, and the like.

Examples of commercially available photoinitiators include the Ciba IRGACURE series from Ciba Specialty Chemicals, the Esacure KIP series from IGM Resins, and the like.

As the thermal initiator, a water-insoluble or water-insoluble (ie, oil-soluble) thermal initiator may be selected and used depending on the polymerization method used.

Examples of the water-soluble initiator include persulfates such as potassium persulfate, ammonium persulfate, sodium persulfate, and mixtures thereof; Redox initiators such as the reaction product of a persulfate with a reducing agent such as metabisulfite (eg sodium metabisulfite) or bisulfate (eg sodium bisulfate); Or 4,4′-azobis (4-cyanopentanoic acid) and soluble salts thereof (eg, sodium salts, potassium salts) and the like.

Examples of the oil-soluble initiator include 2,2'-azobis (2-methylbutanenitrile), 2,2'-azobis (isobutyronitrile) and 2,2'-azobis (2,4-dimethylpentanenitrile. Azo, such as); Or peroxides such as benzoyl peroxide, cyclohexane peroxide and lauroyl peroxide.

Crosslinking agent

Adhesive composition according to the embodiment comprises a crosslinking agent.

The crosslinking agent may react with the base polymer to form a film or the like.

The content of the crosslinking agent in the composition may be 0.1 part by weight to 20 parts by weight based on 100 parts by weight of the base polymer. Specifically, the content of the crosslinking agent may be 0.1 part by weight to 10 parts by weight, or 0.1 part by weight to 5 parts by weight based on 100 parts by weight of the base polymer. In this case, the content of the crosslinking agent and the base polymer may be based on a solid content.

The crosslinking agent may contain a functional group reactive with the functional group of the base polymer.

For example, the crosslinking agent may have one or two or more functional groups selected from the group consisting of an epoxy group, an isocyanate group, a carboxyl group, a hydroxyl group, an acryl group, a methacryl group, an acetate group, and a vinyl group.

As a specific example, the crosslinking agent may have an epoxy group or an isocyanate group.

The crosslinking agent may be a photocrosslinking agent, a thermal crosslinking agent, or a combination thereof.

As the photocrosslinking agent, a conventional polyfunctional acrylic compound can be used.

For example, the photocrosslinker may be at least one selected from the group consisting of diacrylate and triacrylate. Specific examples of the photocrosslinking agent include 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate (HDDA), 1,9-nonanediol diacrylate, tripropylene glycol diacrylate, tetraethylene glycol Diacrylate, trimethylol propane triacrylate, and pentaerythritol triacrylate are mentioned.

The thermal crosslinking agent may be an isocyanate-based, epoxy-based, or metal chelate-based compound.

The isocyanate compound may be a polyfunctional aromatic or aliphatic isocyanate compound. For example, the isocyanate compound may be a trimerized isocyanate such as toluene diisocyanate-trimethylolpropane adduct (TDI-TMP adduct).

The epoxy compound may have one or more epoxy groups, and may have a functional group that is reactive with the base polymer.

The metal chelate compound may be, for example, a chelate compound having a metal such as Zn, Ni, Mn, Fe, Co, Cr, Al, Ti, Zr, or the like.

An example of a commercially available thermal crosslinker is the Saivinol hardener series from Saiden Chemical Industry.

Second monomer

The adhesive composition according to the embodiment may further include a second monomer different from the first monomer.

The second monomer may form additional bonds when the base polymer is reacted with a crosslinking agent. As such, when the base polymer reacts with the crosslinking agent, the second monomer may also react with each other to increase the curing density, and as a result, the first adhesive force may be reduced.

The content of the second monomer in the composition may be 10 parts by weight to 120 parts by weight based on 100 parts by weight of the base polymer. Specifically, the content of the second monomer in the composition may be 20 parts by weight to 110 parts by weight, 30 parts by weight to 100 parts by weight, or 40 parts by weight to 90 parts by weight based on 100 parts by weight of the base polymer.

In this case, the content of the base polymer and the second monomer may be based on solid content.

In addition, the total content in the composition of the first monomer and the second monomer may be 60 parts by weight or more based on 100 parts by weight of the base polymer. Specifically, the total content in the composition of the first monomer and the second monomer may be 60 parts by weight to 200 parts by weight, or 60 parts by weight to 150 parts by weight based on 100 parts by weight of the base polymer.

In this case, the content of the base polymer, the first monomer and the second monomer may be based on solid content.

In the reaction of the base polymer and the crosslinking agent, the second monomer may also react with each other to increase the curing density.

Specifically, the second monomer may lower the adhesion of the reaction product of the base polymer and the crosslinking agent before the polymerization.

In particular, the adhesion between the reaction product of the base polymer and the crosslinking agent is lower before the polymerization of the first monomer when the first monomer and the second monomer are present, as compared with the case where only the first monomer is present. On the other hand, after the polymerization can be further increased to show a more rapid improvement in adhesion.

The molecular weight of the second monomer may range from 50 to 1000, or from 100 to 500.

The second monomer may be a monofunctional or bifunctional compound, for example, a monofunctional to trifunctional compound.

In addition, the second monomer may have one or more functional groups selected from the group consisting of a carboxyl group, a hydroxyl group, an acryl group, a methacryl group, an acetate group and a vinyl group.

As a specific example, the second monomer may have functional groups at both ends.

As an example, the second monomer may be one or more compounds represented by the following Chemical Formula 2.

[Formula 2]

N is an integer of 1-5.

Specifically, the second monomer may be 2-carboxyethyl acrylate, 2-carboxy (EO) ethyl acrylate, 2-carboxy (EO) ₂ ethyl acrylate, 2-carboxy (EO) ₃ ethyl acrylate, or carboxy ( EO) ₄ ethylacrylate.

menstruum

The adhesive composition according to the embodiment may further include a solvent.

The solvent may serve to adjust the viscosity of the adhesive composition.

The kind of the solvent is not particularly limited, but for example, the solvent may be at least one selected from the group consisting of toluene, hexane / methylethylketone mixture, xylene, and isopropyl acetate.

The blending amount of the solvent is not particularly limited, but for example, the solid content of the adhesive composition may be blended in a range of 40 wt% to 90 wt%, or 50 wt% to 80 wt%.

additive

The adhesive composition according to the embodiment may further include other additives as necessary.

Specific examples of such additives include tackifiers (eg, rosin esters, terpenes, phenols, and aliphatic synthetic hydrocarbon resins, aromatic synthetic hydrocarbon resins, or mixtures of aliphatic synthetic hydrocarbon resins and aromatic synthetic hydrocarbon resins), surfactants, plasticizers (Other than physical blowing agents), nucleating agents (eg talc, silica, or TiO ₂ ), fillers (eg inorganic fillers and organic fillers), fibers, aging inhibitors, antioxidants, UV-absorbers, static electricity Inhibitors, lubricants, pigments, dyes, reinforcing agents, hydrophobic or hydrophilic silica, calcium carbonate, toughening agents, flame retardants, finely ground polymeric particles (e.g. polyester, nylon, or polypropylene), stabilizers (Eg, UV stabilizers), and combinations thereof.

The content of the additive is not particularly limited as an amount suitable for obtaining the desired properties of the composition, but may be, for example, 0.1% to 10% by weight or 0.1% to 5% by weight based on the weight of the adhesive composition. have.

Specific composition example

Adhesive composition according to the embodiment may be configured such that the various components exemplified above have a specific content.

According to one embodiment, the adhesive composition may include 100 parts by weight of the base polymer, 0.1 to 20 parts by weight of the crosslinking agent, 10 to 120 parts by weight of the first monomer, and 0.1 to 10 parts by weight of the photopolymerization initiator.

According to another embodiment, the adhesive composition is 100 parts by weight of the base polymer, 0.1 to 20 parts by weight of the crosslinking agent, 10 to 120 parts by weight of the first monomer, 10 to 120 parts by weight of the second monomer, and 0.1 to the initiator. It may include 10 parts by weight.

According to another embodiment, the adhesive composition is 100 parts by weight of a pressure-sensitive adhesive (PSA) as the base polymer, 0.1 to 20 parts by weight of a thermal crosslinking agent as the crosslinking agent, 10 to 120 parts by weight of the compound of Formula 1 as the first monomer , And 0.1 to 10 parts by weight of the photoinitiator as the initiator.

According to another embodiment, the adhesive composition is 100 parts by weight of a pressure-sensitive adhesive (PSA) as the base polymer, 0.1 to 20 parts by weight of a thermal crosslinking agent as the crosslinking agent, 10 to 120 parts by weight of the compound of Formula 1 as the first monomer 10 to 120 parts by weight of the compound of Formula 2 as the second monomer, and 0.1 to 10 parts by weight of the photoinitiator as the initiator.

At this time, the content of the components in the adhesive composition may be based on solids.

Method of Preparation Adhesive Composition

The adhesive composition according to the embodiment may be prepared by mixing the base polymer, the first monomer, the crosslinking agent and the initiator, and further mixing the solvent and other additives as necessary.

The base polymer may be prepared by conventional methods such as solution polymerization.

The mixing order and conditions of a base polymer, a 1st monomer, a crosslinking agent, and an initiator at the time of manufacture of the said adhesive composition are not specifically limited, A process can be modified suitably as needed.

In addition, the viscosity may be adjusted using a solvent in each mixing step.

However, the manufacturing method of the said adhesive composition is not specifically limited, If necessary, process conditions can be modified suitably.

The adhesive composition according to the embodiment may be used to form an adhesive film whose adhesive force is changed, and may be usefully applied in a process requiring adhesive force variability, such as manufacturing an OLED display panel.

Adhesive film

According to another aspect of the present invention, there is provided an adhesive film formed from the adhesive composition.

The adhesive film has improved adhesion after polymerization than before polymerization of the first monomer.

An adhesive film according to an embodiment is an adhesive film comprising a reaction product of a base polymer and a crosslinking agent, wherein the adhesive film contains a first monomer and an initiator and the first monomer is polymerizable by the initiator, and the adhesive film Has a first adhesive force before the polymerization of the first monomer and a second adhesive force after the polymerization of the first monomer, and the second adhesive force is higher than the first adhesive force.

Components of adhesive film

The adhesive film according to the embodiment includes a reaction product of the base polymer and the crosslinking agent. Ie the adhesive film comprises a crosslinked base polymer.

In addition, the adhesive film including the reaction product of the base polymer and the crosslinking agent contains the first monomer and the initiator.

For example, the first monomer and the initiator are dispersed in the reaction product of the base polymer and the crosslinking agent.

The first monomer may be miscible with the reaction product of the base polymer and the crosslinking agent.

Referring back to FIG. 1, polymerization of the first monomer may be initiated by the action of the initiator, if necessary, to improve adhesion of the adhesive film.

Specific types and contents of the base polymer, the crosslinking agent, the first monomer, and the initiator included in the adhesive film are as described above in the adhesive composition.

In addition, the adhesive film according to the embodiment may further include a second monomer different from the first monomer, the second monomer may form additional bonds in the reaction product of the base polymer and the crosslinking agent.

Specific types and contents of the second monomer are the same as those exemplified in the second monomer included in the adhesive composition.

In addition, the adhesive film according to the embodiment may further include other additives, and specific types and contents thereof are as exemplified in the additives included in the adhesive composition.

Characteristics of adhesive film

Adhesion-before and after polymerization of the first monomer

The adhesive film according to the embodiment has a first adhesive force before the polymerization of the first monomer.

The first adhesive force is preferably lower than a certain level in order to remove the unnecessary portion after attaching the adhesive film to the substrate.

For example, the first adhesive force may be 200 gf / in or less, 150 gf / in or less, 100 gf / in or less, 50 gf / in or less, or 30 gf / in or less.

Specifically, the first adhesive force may range from 1 gf / in to 200 gf / in, 1 gf / in to 100 gf / in, or 1 gf / in to 30 gf / in.

In the present specification, the adhesive force (first adhesive force, second adhesive force, etc.) may be measured according to ASTM D3330, which is a general measuring method in the art, and may be, for example, adhesive force measured on polyimide. Examples of more detailed measurement methods have been described in detail in the Examples below.

The adhesive film according to the embodiment has a second adhesive force after the polymerization of the first monomer.

The second adhesive force is preferably higher than a certain level in order to fix the remaining portion to the substrate after removing the unnecessary portion of the adhesive film.

For example, the second adhesive force may be 350 gf / in or more, 400 gf / in or more, 500 gf / in or more, or 1,000 gf / in or more.

Specifically, the second adhesive force may range from 350 gf / in to 10,000 gf / in, or from 500 gf / in to 5,000 gf / in.

The second adhesive force is higher than the first adhesive force.

For example, the second adhesive force may be 150 gf / in or more, 200 gf / in or more, 500 gf / in or more, or 1000 gf / in or more than the first adhesive force.

In addition, the ratio of the second adhesive force to the first adhesive force may be 3 or more, 5 or more, 10 or more, 12 or more, or 15 or more.

In addition, the ratio of the first adhesive force to the second adhesive force may be 0.06 or less, 0.03 or less, 0.02 or less, or 0.01 or less.

As an example, the first adhesive force may be 200 gf / in or less, and the second adhesive force may be 350 gf / in or more.

As another example, the first adhesive force may be 150 gf / in or less, and the second adhesive force may be 400 gf / in or more.

As another example, the first adhesive force may range from 1 gf / in to 30 gf / in, and the second adhesive force may range from 500 gf / in to 5000 gf / in.

In addition, the adhesive film formed by crosslinking the base polymer without the first monomer may have an adhesive force between the first adhesive force and the second adhesive force.

Haze after monomer polymerization, transmittance

The adhesive film may satisfy the requirements as an optically transparent adhesive film.

For example, the adhesive film may have a haze of 5% or less, 2% or less, or 1% or less after polymerization of the first monomer.

In addition, the adhesive film, the light transmittance after the polymerization of the first monomer may be 80% or more, 90% or more, or 95% or more.

Even when the said adhesive film further contains the said 2nd monomer, it can satisfy the requirement as an optically transparent adhesive film.

For example, when the adhesive film includes the first monomer and the second monomer, the haze after polymerization may be 5% or less or 2% or less.

In addition, the adhesive film, when including the first monomer and the second monomer, the light transmittance after polymerization may be 80% or more or 90% or more.

Film thickness

The thickness of the adhesive film may be in the range of 5 μm to 1000 μm, or 10 μm to 100 μm when prepared as a thin film.

Alternatively, the thickness of the adhesive film may be in the range of 0.1 mm to 5 mm, or in the range of 1 mm to 3 mm when manufactured into a thick film.

Manufacturing method of adhesive film

The adhesive film may be prepared by preparing an adhesive composition and then forming the film.

In one embodiment, a method of preparing an adhesive film includes mixing a base polymer, a first monomer, an initiator, and a crosslinking agent; Reacting the crosslinking agent with the base polymer to form a film-shaped polymer; And preserving the first monomer and the initiator in the film-like polymer to obtain an adhesive film.

The step of preparing the adhesive composition may be performed according to the conditions and procedures as exemplified above. The reaction of the crosslinking agent and the base polymer may be performed by a conventional thermosetting process. For example, the thermosetting temperature may range from 40 ° C. to 150 ° C., from 60 ° C. to 150 ° C., from 60 ° C. to 120 ° C., or from 100 ° C. to 120 ° C., and the heat cure time from 1 minute to 10 minutes, or Minutes to 5 minutes, but these thermosetting conditions can be adjusted depending on the length and number of curing ovens. In addition, it may be further subjected to aging (eg, aged at about 50 ° C. for 3 days) after the thermosetting.

The thermosetting process may be performed when the adhesive composition is coated on the base film. Specifically, the adhesive composition may be coated on a base film with an appropriate thickness, and heat curing may be performed in this process. The coating may be performed by a method such as notch bar, comma, gravure, or die coating. The coating speed may also be in the range of about 1 m / min to 40 m / min, or in the range of 5 m / min to 30 m / min, but the conditions may be adjusted according to the length of the curing oven.

In addition, the step of preserving the first monomer and the initiator in the film-shaped polymer, inhibits the environment in which the initiator can act in the coated (and thermoset) film-shaped polymer (for example, UV light exposure prevention) It can be done by doing.

Application with adhesive tape

The adhesive film according to the embodiment may be applied as an adhesive tape.

4 illustrates a cross-sectional view of an adhesive tape including an adhesive film according to one embodiment.

Referring to FIG. 4, the adhesive film 110 according to the embodiment may be formed on one surface of the base film 120 to provide a base type adhesive tape 100.

In addition, in the adhesive tape, the release film 130 may be laminated on one surface of the adhesive film 110.

Base film

The base film may include at least one resin selected from the group consisting of polyester resins, polyurethane resins, and polyolefin (polyethylene, etc.) resins. Alternatively, the base film may be composed of paper, plastic film, cloth, or metal foil.

In some embodiments, materials suitable for the base film include, for example, paper, including both flat or smooth paper, as well as textured paper such as crepe paper, natural or synthetic polymer films, natural and / or synthetic fibers, and these Nonwovens, fiber reinforced polymer films, fiber or yarn reinforced polymer films or nonwovens, and multilayer laminate structures made from combinations thereof.

In addition, the base film may have a thickness in the range of 5 μm to 100 μm, or in the range of 10 μm to 100 μm. As an example, the base film may include polyethylene terephthalate and have a thickness of 10 μm to 100 μm.

Such an adhesive tape may be manufactured by a method comprising applying the adhesive composition to at least one surface of a base film to form an adhesive film.

At this time, after application of the adhesive composition, it is necessary to prevent the first monomer in the adhesive film from polymerizing until the use of the adhesive tape.

Alternatively, the adhesive film according to the embodiment may be provided as an adhesive tape of the inorganic material type as such, without a base film.

Adhesive film

In the adhesive tape, the adhesive film 110 may be an adhesive film according to one embodiment described above.

Accordingly, the adhesive tape may include an adhesive film having the composition and properties described above.

Release film

The type of release film used for the adhesive tape is not particularly limited, but may be, for example, at least one member selected from the group consisting of polyester (PET) film, polyethylene (PE) film, polypropylene (PP) film, and paper. .

In addition, the release film may include a silicon coating layer on the surface in contact with the adhesive film.

The release film may have a thickness of 5 μm to 100 μm, but may be thinner or thicker as needed.

Laminate

According to another aspect of the invention, there is provided a laminate comprising a substrate and an adhesive film according to the above embodiment.

Component of the laminate

The substrate in the laminate may be made of a material such as metal, glass, polymer.

Specifically, the material of the substrate may be stainless steel, glass, polyolefin, polyimide, and the like.

More specifically, the substrate may include polyimide.

The substrate may be attached with an adhesive film as a whole on its surface.

Alternatively, an adhesive film may be partially attached to the substrate, such that the laminate may have an adhesive film application region and an adhesive film non-application region.

The adhesive film application region and the adhesive film non-application region in the laminate may each be one or more, they may form a specific pattern.

The adhesive film in the laminate may be an adhesive film according to the embodiment described above. Accordingly, the laminate structure may include an adhesive film having the composition and properties described above.

Manufacturing method of laminate

5 shows an example of a manufacturing method of the laminate.

Referring to FIG. 5, the method of manufacturing the laminate may include applying an adhesive film 110 to the substrate 200 according to the embodiment; Removing a portion of the adhesive film 110 to form an adhesive film application region and an adhesive film non-application region on the substrate 200; And polymerizing the first monomer contained in the adhesive film 111 of the adhesive film application region with an initiator to improve the adhesive force of the adhesive film 111 of the adhesive film application region.

In addition, the manufacturing method of the laminate comprises the steps of preparing an adhesive composition according to the embodiment; Reacting the base polymer with the crosslinking agent to form an adhesive film in which the first monomer and the initiator are preserved; Applying the adhesive film to a substrate; Removing a portion of the adhesive film to form an adhesive film application region and an adhesive film non-application region on the substrate; And polymerizing the first monomer contained in the adhesive film of the adhesive film application region by the initiator to improve the adhesion of the adhesive film of the adhesive film application region.

As a result, the adhesive film after the polymerization of the first monomer may have improved adhesion as compared to the adhesive film before the polymerization of the first monomer.

In the manufacturing method of the laminate, the step of preparing the adhesive composition and the step of preparing the adhesive film may be carried out under the conditions as described above.

In addition, the step of removing a portion of the adhesive film to form an adhesive film application region and an adhesive film non-application region on the substrate, so that the resulting adhesive film on the adhesive film application region has the shape of lines, figures, patterns and the like. Can be performed.

As an example, a cutting line is formed on the surface of the adhesive film applied to the substrate in the form of a dotted line or the like along the periphery of the desired area, and then adhered along the cutting line by slowly lifting by attaching an adhesive tape or the like to the area to be removed. A portion of the film can be removed.

In addition, the step of polymerizing the first monomer may be performed by a conventional photocuring or thermosetting process.

Referring to FIG. 5, the polymerizing of the first monomer may be performed by irradiating UV light 300 to the adhesive film 111 on the adhesive film application region. Irradiation of the UV light may be performed under an energy condition of 500 mJ / cm ² to 3,000 mJ / cm ² in a wavelength range of 250 nm to 420 nm.

Device

According to another aspect of the present invention, an apparatus including the laminate is provided.

A specific kind of the device is not particularly limited, but may be, for example, a display device.

According to an exemplary embodiment, a display apparatus includes a display panel; And a laminate according to the embodiment attached on the display panel.

The display panel may be an organic light emitting display (OLED) display panel or a liquid crystal display (LCD) panel.

EXAMPLE

The present invention will be described in more detail with reference to the following Examples. However, these Examples are only illustrative of the present invention, and the present invention is not limited thereto.

Preparation Example 1 Preparation of Base Polymer

Each base polymer (adhesive) was prepared by solution polymerization using the components in the table below.

division Glue A Glue B Glue C Glue D Glue E
glue
Furtherance
(Part by weight) 2-EHA 70 70 BA 50 74 73 MA 30 45 30 26 25 VAc 5 AA 2 2 2 2-HEA 0.3 0.3 0.3 1.9 2 EA / toluene / acetone 153.5 240 153.5 237.7 240 Solid content (% by weight) 40 30 40 30 30

2-EHA: 2-ethylhexyl acrylate

BA: Butyl acrylate

MA: methyl acrylate

-VAc: vinyl acetate

AA: acrylic acid

2-HEA: 2-hydroxyethyl acrylate

EA: ethyl acetate

Example 1 Preparation of Adhesive Composition

The base polymer (adhesive A or B) obtained in Preparation Example 1 is mixed with a UV monomer, a solvent for adjusting the viscosity (EA) and other additives is added if necessary, and then stirred for 30 minutes to 1 hour to prepare a first solution. Was prepared. Solvent (EA) was added to the photoinitiator in a weight ratio of 1: 2 to prepare a second solution. The first solution, the second solution and the crosslinking agent were mixed, a solvent for adjusting the viscosity (EA) was added if necessary, and then stirred for 30 minutes to 1 hour to prepare an adhesive composition.

At this time, the components and contents of each material in the final composition are shown in the following table.

Adhesive composition (unit: parts by weight) 1E 1F 1G 1H 1I glue B 100 100 100 100 100 Crosslinking agent Isocyanate 2.0 2.0 2.0 2.0 2.0 Metal (Al) Chelate System 1.0 1.0 1.0 1.0 1.0 UV
Monomer Lauryl acrylate 5
(17) 10
(33) 15
50 18
(60) 25
(83) Photoinitiator IRGACURE 651 1.8 1.8 1.8 2.5 1.8

* The numerical values in parentheses in the above table are parts by weight based on 100 parts by weight of the adhesive solids.

-Isocyanate crosslinking agent: 45% solids, Saivinol hardener AL, Saiden Chemical Industry

-Metal (Al) chelate crosslinker: 5% solids, Saivinol hardener M-2, Saiden Chemical Industry

-Lauryl acrylate

-Ciba ™ IRGACURE 651

Test Example 1-1: Measurement of Adhesion to Polyimide

(1) Preparation of Sample

The adhesive composition to be tested was coated on a 75 μm thick polyethylene terephthalate (PET) film at a rate of 1.0 m / min. Drying was carried out in a total of 6 m oven with 3 m 2 drying zones (temperatures of 40 ° C., 80 ° C. and 120 ° C., respectively). As a result, an adhesive film having a thickness of 13 μm was formed on the PET film, which was cut to 1 inch × 12 mm to obtain a single-sided tape sample.

(2) Adhesion measurement before and after UV curing

A polyimide film (manufacturer: SKC Kolon PI) was attached using a PET double-sided tape on a rigid acrylic plate or glass plate. The surface of the said polyimide film was wash | cleaned with isopropanol / heptane, the previously produced single sided tape sample was laminated | stacked, and the laminated body was obtained. Preparation of the above laminate was completed within 1 hour in order to minimize the effect of light in the working process.

The laminate was cured in a UV curing machine (metal halide lamp, wavelength range 250-420 nm, dominant wavelength 365 nm, energy 1,000 mJ / cm ² ). At this time, before and after UV curing, the 180 ° peeling strength between polyimide films of the single-sided tape in the laminate was measured. Peel strength (adhesive strength) was measured using a universal testing machine (UTM, TA Instrument) according to ASTM D3330 at a peel rate of 305 mm / min and a load of 2 kgf. The results are shown in the table below.

In addition, for comparison, a single-sided tape sample was made only with an adhesive (base polymer), and the adhesion to the polyimide film was measured under the same conditions, and is shown in the following table.

Adhesive composition Adhesion to Polyimide Film (gf / in) Glue only Adhesive composition
-Before UV Curing Adhesive composition
-After UV curing 1E 1,150 800 1,200 1F 1,150 200 1,200 1G 1,150 100 1,300 1H 1,150 30 1,400 1I 1,150 30 1,400

As shown in the above table, the adhesive compositions according to the examples have increased adhesion after UV curing compared to before UV curing, and have lower adhesion before UV curing and more before UV curing compared to the adhesive (base polymer) only. It can be seen that it has a high adhesion. In particular, when the weight of the first monomer is 60 parts by weight or more relative to 100 parts by weight of the solid content of the base polymer, it can be seen that the difference in adhesion before and after UV curing is significantly increased.

Test Example 1-2: Measurement of Adhesion to Various Substrates

The same procedure as in Test Example 1-1 was repeated, but before and after UV curing of the single-sided tape sample to stainless steel, glass instead of the polyimide film was measured, the results are shown in the table below.

In addition, for comparison, a single-sided tape sample was produced using only an adhesive (base polymer), and the adhesion to stainless steel and glass was measured, and the results are shown in the following table.

Adhesive composition Adhesion Prior to UV Curing (gf / in) Stainless steel Glass 1E 980 920 1F 350 300 1G 150 100 1H 50 30 1I 50 30

Adhesive composition Adhesion after UV Curing (gf / in) Stainless steel Glass 1E 1400 1,350 1F 1450 1,300 1G 1350 1,250 1H 1450 1,300 1I 1400 1,300

glue Adhesive force (gf / in) Stainless steel Glass A 730 650 B 1,130 850

As shown in the above table, the adhesive compositions according to the embodiments have increased adhesion after UV curing even on various substrates, especially lower adhesion before UV curing compared to the adhesive (base polymer) only. It was found to have higher adhesion before UV curing.

Test Example 1-3: Static Shear Stress Evaluation

In the same manner as in Test Example 1-1, a 1 inch x 1 inch sized single-sided tape sample was prepared and its static shear was evaluated. At this time, the static shear stress evaluation was carried out by measuring the period of falling adhesion to stainless steel at 500 g load and 60 ℃ / 90% RH conditions. The results are shown in the table below.

Static shear stress evaluation (unit: day) Adhesive composition 1E 1F 1G 1H 1I Glue only 7 ↑ 7 ↑ 7 ↑ 7 ↑ 7 ↑ After UV curing 7 ↑ 7 ↑ 7 ↑ 7 ↑ 7 ↑

As shown in the table, the adhesive compositions according to the examples had a static shear stress after various UV curing equal or more than the conventional adhesive.

Example 2: Preparation of Adhesive Composition

Under the same conditions as in Example 1, each adhesive composition was prepared by combining an adhesive, a crosslinking agent, a UV monomer, and a photoinitiator of the components and contents shown in the following table.

Adhesive composition (unit: parts by weight) 2A 2B 2C 2D 2E 2F 2G 2H glue C 100 100 100 100 D 100 100 100 100 Crosslinking agent Isocyanate 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 Epoxy 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 UV
Monomer Phenyl (EO) nacrylate 10
(25) 15
(38) 18
(45) 25
(63) 18
(60) 12
40 9
(30) o-phenylphenol EOacrylate 6
20 9
(30) 18
(60) Photoinitiator IRGACURE 651 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9

* The numerical values in parentheses in the above table are parts by weight based on 100 parts by weight of the adhesive solids.

-Isocyanate crosslinking agent: 45% solids, Saivinol hardener AL, Saiden Chemical Industry

-Epoxy-based crosslinking agent: 5% solids, NA-30, Cosmotech

Phenyl (EO) nacrylate (n = 2)

o-phenylphenol EOacrylate

-Ciba ™ IRGACURE 651

Test Example 2 Measurement of Adhesion to Polyimide

A single-sided tape sample was prepared in the same manner as in Test Example 1-1 using the respective adhesive compositions (2A to 2H) prepared in Example 2, and its adhesive strength before and after UV curing to the polyimide film was measured. It measured and the result is shown in the following table | surface. In addition, for comparison, a single-sided tape sample was made only with an adhesive (base polymer), and the adhesion to the polyimide film was measured under the same conditions, and is shown in the following table.

Adhesive composition Adhesion to Polyimide Film (gf / in) Glue only Adhesive composition
Before UV Curing Adhesive composition
After UV curing 2A 830 170 900 2B 830 90 1,000 2C 830 30 1,200 2D 830 40 1,200 2E 250 20 1,200 2F 250 30 2,100 2G 250 30 2,200 2H 250 30 2,300

As shown in the above table, the adhesive compositions according to the embodiment showed a significant increase in adhesion after UV curing for various substrates, and lower adhesion before UV curing compared to the adhesive (base polymer) alone. It was found to have higher adhesion before UV curing. In particular, when the weight of the first monomer is 60 parts by weight or more relative to 100 parts by weight of the solid content of the base polymer, it can be seen that the difference in adhesion before and after UV curing is significantly increased.

Example 3: Preparation of Adhesive Composition

Under the same conditions as in Example 1, each adhesive composition was prepared by combining an adhesive, a crosslinking agent, a UV monomer, and a photoinitiator of the components and contents shown in the following table.

Adhesive composition (unit: parts by weight) 3A 3B 3C 3D 3E 3F 3G 3H glue E 100 100 100 100 100 100 100 100 Crosslinking agent Isocyanate 4 4 4 4 4 6 4 4 Epoxy 2 2 2 2 2 2 2 2 UV
Monomer Phenyl (EO) nacrylate 9
(30) 9
(30) 9
(30) 9
(30) 9
(30) 9
(30) 18
(60) 12
40 2-carboxyethyl acrylate 9
(30) 14
(47) 20
(67) 25
(83) 33
(110) 14
(47) Photoinitiator IRGACURE 651 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9

* The numerical values in parentheses in the above table are parts by weight based on 100 parts by weight of the adhesive solids.

-Isocyanate crosslinking agent: 45% solids, Saivinol hardener AL, Saiden Chemical Industry

-Epoxy-based crosslinking agent: 5% solids, NA-30, Cosmotech

Phenyl (EO) nacrylate (CAS No. 56641-05-5) (n = 2)

2-carboxyethyl acrylate (CAS No. 56641-05-5)

-Ciba ™ IRGACURE 651

Test Example 3 Measurement of Adhesion to Polyimide

A single-sided tape sample was prepared in the same manner as in Test Example 1-1 using the respective adhesive compositions (3A to 3H) prepared in Example 3, and the adhesion before and after UV curing to the polyimide film was measured. It measured and the result is shown in the following table | surface. In addition, changes in adhesion before and after UV curing, depending on the content (parts by weight) of 2-carboxyethyl acrylate as additional UV monomers, are shown in FIGS. 6A and 6B, respectively.

Adhesive composition Adhesion to Polyimide Film (gf / in) Before UV Curing After UV curing 3A 20 1030 3B 11 1740 3C 9 1980 3D 2 2120 3E 0 2170 3F 9 840 3G 18 780 3H 25 500

As shown in the table and in FIGS. 6A and 6B, the adhesive compositions according to the examples significantly increased the adhesion after UV curing for various substrates as compared to before UV curing. In particular, as the content of 2-carboxyethyl acrylate as an additional UV monomer increased, the adhesion decreased before UV curing, whereas the adhesion increased after UV curing.

Example 4: Preparation of Adhesive Composition

Under the same conditions as in Example 1, each adhesive composition was prepared by combining an adhesive, a crosslinking agent, a UV monomer, and a photoinitiator of the components and contents shown in the following table.

Adhesive composition (unit: parts by weight) 4A 4B 4C 4D 4E glue E 100 100 100 100 100 Crosslinking agent Isocyanate 4 4 4 4 4 Epoxy 2 2 2 2 2
UV Monomer SA 9 (30) HDDA 9 (30) BA 9 (30) IBOA 9 (30) 2-EHA 9 (30) 2-carboxyethyl acrylate 14
(47) 14
(47) 14
(47) 14
(47) 14
(47) Photoinitiator IRGACURE 651 0.9 0.9 0.9 0.9 0.9

* The numerical values in parentheses in the above table are parts by weight based on 100 parts by weight of the adhesive solids.

-Isocyanate crosslinking agent: 45% solids, Saivinol hardener AL, Saiden Chemical Industry

-Epoxy-based crosslinking agent: 5% solids, NA-30, Cosmotech

SA: stearyl acrylate

HDDA: 1,6-hexanedioldiacrylate

BA: benzyl acrylate

IBOA: isobornyl acrylate

2-EHA: 2-ethylhexyl acrylate

2-carboxyethyl acrylate

-Ciba ™ IRGACURE 651

Test Example 4 Measurement of Adhesion to PI Film

A single-sided tape sample was prepared in the same manner as in Test Example 1-1 using the respective adhesive compositions 4A to 4E prepared in Example 4, and its adhesive strength before and after UV curing to the polyimide film was measured. It measured and the result is shown in the following table | surface.

In addition, the compatibility of the UV monomer with the adhesive in each adhesive composition was evaluated and shown in the following table.

Also for comparison, the results of evaluation of physical properties of the adhesive compositions prepared in Examples 2 and 3 are also shown in the following table.

glue
Composition Miscibility Adhesion to Polyimide Film (gf / in) Remarks Adhesive composition
Before UV Curing Adhesive composition
After UV curing 4A good 30 700 4B usually 40 500 4C good 30 700 4D good 100 700 4E Bad 150 400 2E good 20 1200 Manufactured in Example 2 3B good 11 1740 Manufactured in Example 3

100: adhesive tape, 110: adhesive film according to one embodiment,
111: adhesive film on the adhesive film application area,
120: base film, 130: release film,
200: substrate, 300 UV light.

Claims (16)

Base polymers;
A crosslinking agent reacted with the base polymer;
A first monomer polymerized after the reaction of the base polymer and the crosslinking agent; And
As an adhesive composition containing the initiator which polymerizes a said 1st monomer,
After the reaction of the base polymer and the crosslinking agent, the first adhesive force before the polymerization of the first monomer and the second adhesive force after the polymerization of the first monomer, the second adhesive force is higher than the first adhesive force, Adhesive composition.
The method of claim 1,
The adhesive composition having a haze of 2% or less after polymerization of the first monomer.
The method of claim 1,
Wherein said base polymer contains functional groups reactive with said crosslinking agent.
The method of claim 1,
The adhesive composition is
The adhesive composition further comprising a second monomer different from the first monomer.
The method of claim 4, wherein
Wherein said second monomer forms an additional bond upon reaction of said base polymer with said crosslinking agent.
An adhesive film comprising a reaction product of a base polymer and a crosslinking agent,
The adhesive film contains a first monomer and an initiator and the first monomer is polymerizable by the initiator,
Wherein said adhesive film has a first adhesive force before polymerization of said first monomer and a second adhesive force after polymerization of said first monomer, and said second adhesive force is higher than said first adhesive force.
The method of claim 6,
The adhesive film has a haze of 2% or less after the polymerization of the first monomer.
The method of claim 6,
Wherein said adhesive film further comprises a second monomer different from said first monomer, said second monomer forming additional bonds in the reaction product of said base polymer and said crosslinking agent.
Mixing the base polymer, the first monomer, the initiator and the crosslinker;
Reacting the crosslinking agent with the base polymer to form a film-shaped polymer; And
A method for producing the adhesive film of claim 6, comprising the step of preserving the first monomer and the initiator in the film-like polymer to obtain an adhesive film.
A laminate comprising a substrate and the adhesive film of claim 6.
The method of claim 10,
The said board | substrate contains polyimide.
The method of claim 10,
The laminate, wherein the laminate has an adhesive film application region and an adhesive film non-application region.
Applying the adhesive film of claim 6 to the substrate;
Removing a portion of the adhesive film to form an adhesive film application region and an adhesive film non-application region on the substrate; And
And polymerizing the first monomer contained in the adhesive film of the adhesive film application region by the initiator to improve the adhesion of the adhesive film of the adhesive film application region.
Preparing the adhesive composition of claim 1;
Reacting the base polymer with the crosslinking agent to form an adhesive film in which the first monomer and the initiator are preserved;
Applying the adhesive film to a substrate;
Removing a portion of the adhesive film to form an adhesive film application region and an adhesive film non-application region on the substrate; And
And polymerizing the first monomer contained in the adhesive film of the adhesive film application region by the initiator to improve the adhesion of the adhesive film of the adhesive film application region.
An apparatus comprising the laminate of claim 10.
Display panel; And
A display device comprising the laminate of claim 10 attached on the display panel.

Images