KR20210032917A - Acrylate based emulsion adhesive composition - Google Patents

Abstract

The present invention relates to an acrylic emulsion adhesive composition comprising emulsion polymer particles. According to the present invention, the acrylic emulsion adhesive composition has excellent adhesive properties in a wide temperature range by combining a specific monomer with a crosslinking agent and optimizing the content thereof.

Description

Acrylic emulsion adhesive composition {ACRYLATE BASED EMULSION ADHESIVE COMPOSITION}

The present invention relates to an acrylic emulsion pressure-sensitive adhesive composition.

Recently, the use of sticker-type surface finishes such as interior/exterior materials, interior materials, and advertisement materials of buildings to which a pressure-sensitive adhesive (PSA) is applied is increasing significantly. As the adhesive, the existing oil-based adhesive causes symptoms such as headache, irritation of the eyes and nose, cough, itchiness, dizziness, fatigue, and decreased concentration in people living inside the building because residual solvents are discharged into the air for a long period of time after construction. When exposed for a long period of time, problems of sick house syndrome, which cause respiratory disease, heart disease, and cancer, occur.

For this reason, interest in water-based emulsion adhesives that are environmentally friendly and do not discharge harmful substances to the human body by using water as a dispersion medium has been concentrated and rapidly replaced. Aqueous emulsion adhesives can use polymers having a higher molecular weight than solvent-based polymers, regardless of the viscosity of the adhesive and the molecular weight of the dispersion polymer, can obtain a wide range of solids concentration, and have low aging resistance, low viscosity, and low viscosity. It has the advantage of good adhesion in the solid content area and good compatibility with other polymers.

In addition, as the use environment of the pressure-sensitive adhesive has recently been diversified, there is a growing demand for a pressure-sensitive adhesive having excellent low-temperature adhesion and retention in addition to the above-described general adhesion at room temperature.

Conventional techniques have solved the initial adhesive strength, adhesive force and cohesiveness at room temperature of the aqueous emulsion adhesive to some extent, but at the same time, the adhesive having excellent low-temperature adhesive strength and holding power cannot be provided. This is because there is a trade-off relationship between room temperature and low temperature adhesive properties in emulsion adhesives having a specific glass transition temperature, and in the case of emulsion adhesive compositions expressing adhesive properties at room temperature, the adhesive properties generally decrease at room temperature and low temperature. This is because it is difficult to satisfy all of the adhesive strength.

Therefore, a method of using a polymeric binder with a low glass transition temperature to improve adhesion at low temperatures while maintaining normal temperature adhesion has been proposed, but most polymer binders with a low glass transition temperature exhibit non-polarity and increase the non-polarity of the polymerized monomer. Therefore, it causes a problem of polymerization stability of pre-emulsion and emulsion adhesive.

Therefore, there is a high need for a technology of a pressure-sensitive adhesive having excellent adhesion at room temperature and low temperature.

The present invention is to provide an acrylic emulsion adhesive composition excellent in both room temperature and low temperature adhesive strength.

In order to achieve the above object, the present invention,

Alkyl (meth)acrylate-based monomers; Hydroxy group alkyl (meth)acrylate-based monomers; Unsaturated carboxylic acid-based monomers; And by emulsion polymerization of a monomer mixture containing a vinyl-based monomer and a polyalkylene glycol diacrylate-based crosslinking agent,

Containing emulsified polymer particles,

It provides an acrylic emulsion pressure-sensitive adhesive composition having a viscoelastic ratio (Tan delta) of 0.5 to 0.8 measured at a temperature of 25°C and 5.0*10 ^-2 to 1.0*10 ^{2 rad/sec.}

According to the present invention, by optimizing a combination of a specific monomer and a crosslinking agent to achieve a balance between viscosity and elasticity, it is possible to provide an acrylic emulsion pressure-sensitive adhesive composition that exhibits excellent adhesive properties both at room temperature and in a wide temperature range at low temperatures.

1 is a graph showing the viscoelasticity ratio according to the frequency of the acrylic emulsion pressure-sensitive adhesive composition according to Examples and Comparative Examples of the present invention.

In the present invention, terms such as first and second are used to describe various components, and the terms are used only for the purpose of distinguishing one component from other components.

In addition, terms used in the present specification are only used to describe exemplary embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present specification, terms such as "comprise", "include", or "have" are intended to designate the existence of a feature, number, step, element, or combination of the implemented features, but one or more other features or It is to be understood that the possibility of the presence or addition of numbers, steps, elements, or combinations thereof is not preliminarily excluded.

The present invention will be described in detail below and exemplify specific embodiments, as various modifications can be made and various forms can be obtained. However, this is not intended to limit the present invention to a specific form disclosed, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

Hereinafter, an acrylic emulsion pressure-sensitive adhesive composition according to a specific embodiment of the present invention will be described.

The inventors of the present invention control the viscoelasticity ratio within a certain range by combining a specific monomer and a crosslinking agent and optimizing the content in an acrylic emulsion pressure-sensitive adhesive composition comprising an emulsion of latex particles prepared by emulsion polymerization of an acrylate-based monomer. Therefore, it was conceived that the adhesive properties could be expressed in a wide temperature range by showing excellent adhesive properties at both room temperature and low temperature, and the present invention was completed.

Specifically, the acrylic emulsion pressure-sensitive adhesive composition according to an embodiment of the present invention includes an alkyl (meth)acrylate-based monomer; Hydroxy group alkyl (meth)acrylate-based monomers; Unsaturated carboxylic acid-based monomers; And a monomer mixture containing a vinyl-based monomer and a polyalkylene glycol diacrylate-based crosslinking agent emulsion polymerization, including emulsion polymer particles, including the emulsion polymer particles, a temperature of 25 ℃, 5.0 * 10 ^-2 to 1.0 * 10 ² rad / sec It is characterized in that the viscoelastic ratio (Tan delta) measured in the range is 0.5 to 0.8 over the entire frequency range.

First, the acrylic emulsion pressure-sensitive adhesive composition according to an embodiment of the present invention includes an emulsified polymer particle of a specific monomer, that is, a latex particle, and each monomer exists in the form of a repeating unit derived from a monomer in the latex particle. I can.

In the present invention, the monomer mixture for performing the emulsion polymerization process may include an alkyl (meth)acrylate-based monomer; Hydroxy group alkyl (meth)acrylate-based monomers; Unsaturated carboxylic acid-based monomers; And vinyl-based monomers.

In the present specification, the term "monomer mixture" refers to a state in which one or more types of monomers described below are mixed together based on acrylic monomers, and the one or more types of monomers may be added together to be prepared, or sequentially with each other. Bars that can be introduced and manufactured, the manufacturing method is not limited.

Meanwhile, in order to satisfy the above-described viscoelastic ratio of 0.5 to 0.8, the acrylic emulsion pressure-sensitive adhesive composition according to an embodiment of the present invention comprises 85 to 90 of the alkyl (meth)acrylate-based monomer based on 100 parts by weight of the monomer mixture. By weight, 1 to 5 parts by weight of the hydroxy group alkyl (meth)acrylate monomer, 1 to 5 parts by weight of the unsaturated carboxylic acid monomer, 1 to 5 parts by weight of the vinyl monomer, and the polyalkylene glycol di An acrylate-based crosslinking agent may be included in an amount of 0.05 to 0.5 parts by weight.

In addition, the acrylic emulsion pressure-sensitive adhesive composition according to an embodiment of the present invention includes the hydroxy group alkyl (meth)acrylate-based monomer, the unsaturated carboxylic acid-based monomer, and the vinyl-based within a range in which each component satisfies the above-described parts by weight. The relative content ratios between the monomers are to be included similarly to each other, and it is preferable not to exceed twice as much as possible.

For example, the hydroxy group alkyl (meth)acrylate-based monomer. It is preferable that the weight ratio between the unsaturated carboxylic acid-based monomer and each of the two types of monomers selected from the vinyl-based monomer is 0.5 to 2, or 0.7 to 1.8, or 0.9 to 1.1.6, or 0.9 to 1:1.5. As described above, the hydroxy group alkyl (meth)acrylate-based monomer. When the relative contents of the unsaturated carboxylic acid-based monomer and the vinyl-based monomer are similar, the viscoelasticity ratio of 0.5 to 0.8 is satisfied, and accordingly, the room temperature-low temperature adhesive properties may be satisfied at the same time.

Hereinafter, an acrylic emulsion pressure-sensitive adhesive composition according to an embodiment of the present invention will be described in more detail.

a) Alkyl (meth)acrylate monomer

First, in the emulsion polymerization for preparing the latex particles, an alkyl (meth)acrylate-based monomer may be used, and this may be referred to as a first monomer. Accordingly, the latex particle may include a repeating unit derived from an alkyl (meth)acrylate-based monomer, and this may be referred to as a first repeating unit.

The alkyl (meth)acrylate-based monomer is the alkyl (meth)acrylate-based monomer having a C1-C14 alkyl group, that is, an alkyl group having 1 to 14 carbon atoms, and any material known in the art is not limited. For example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, t- Butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth) At least one selected from the group consisting of acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, dodecyl (meth)acrylate, isobornyl (meth)acrylate, and lauryl (meth)acrylate They may be used alone, or two or more of them may be used in combination.

Specifically, one or two or more selected from methyl (meth) acrylate, ethyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate may be preferably used.

The acrylic emulsion pressure-sensitive adhesive composition according to an embodiment of the present invention requires a low glass transition temperature for low-temperature adhesive properties and contains 85 parts by weight or more of the alkyl (meth)acrylate-based monomer for this purpose.

Although the present invention is not limited thereto, for example, the alkyl (meth)acrylate-based monomer is 85 parts by weight or more, or 87 parts by weight or more, or 88 parts by weight, or 89 parts by weight or more based on 100 parts by weight of the monomer mixture. Meanwhile, it may be included in an amount of 99 parts by weight or less, 97 parts by weight or less, or 95 parts by weight or less. When the content of the alkyl (meth)acrylate-based monomer is too small, there may be a problem in that low-temperature adhesive properties are not implemented. In addition, when too much of the alkyl (meth)acrylate-based monomer is included, the transfer of the pressure-sensitive adhesive to the adherend occurs largely upon removal after use, and the washing property is poor, which is not preferable.

b) Hydroxy group alkyl (meth)acrylate monomer

Next, in the emulsion polymerization for preparing the latex particles, a hydroxy group alkyl (meth)acrylate-based monomer may be used, and this may be referred to as a second monomer. Accordingly, the latex particles may include a repeating unit derived from a hydroxy group alkyl (meth)acrylate-based monomer, and this may be referred to as a second repeating unit.

The hydroxyalkyl (meth)acrylate-based monomer may contribute to improving adhesion and peel strength while imparting viscosity to the acrylic emulsion pressure-sensitive adhesive composition.

The hydroxy group alkyl (meth)acrylate-based monomer is 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl It may be at least one selected from the group consisting of (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 2-hydroxyethylene glycol (meth)acrylate, and 2-hydroxypropylene glycol (meth)acrylate And, these may be used alone, or two or more may be mixed and used.

Although the present invention is not limited thereto, for example, the hydroxy group alkyl (meth)acrylate-based monomer is 1 part by weight or more, or 1.5 parts by weight or more, or 2 parts by weight or more based on 100 parts by weight of the monomer mixture, and 5 It may be included in an amount of less than or equal to 4.5 parts by weight, or less than or equal to 4 parts by weight. If too much of the hydroxy group alkyl (meth)acrylate-based monomer is used, the degree of crosslinking decreases, reducing the holding power, and a problem of a large increase in viscosity may occur.If too little is used, the cohesion due to hydrogen bonding of the hydroxy group is increased. You can't expect an effect.

c) unsaturated carboxylic acid monomer

Next, in the emulsion polymerization for preparing the latex particles, an unsaturated carboxylic acid-based monomer may be used, and this may be referred to as a third monomer. Accordingly, the latex particle may include a repeating unit derived from an unsaturated carboxylic acid-based monomer, and this may be referred to as a third repeating unit.

The unsaturated carboxylic acid-based monomer controls softness and hardness by controlling the degree of internal crosslinking of the emulsified polymer particles so that the acrylic emulsion pressure-sensitive adhesive composition can achieve appropriate viscoelastic properties.

The unsaturated carboxylic acid monomers include acrylic acid, fumaric acid, maleic acid, itaconic acid, citraconic acid, mesaconic acid, and text. Rutaconic acid (glutaconic acid), and may include at least one selected from the group consisting of allylmalonic acid (allylmalonic acid).

Although the present invention is not limited thereto, for example, the unsaturated carboxylic acid-based monomer is 1 part by weight or more, or 1.5 parts by weight or more, or 2 parts by weight or more, and 5 parts by weight or less based on the total 100 parts by weight of the monomer mixture. , Or 4.5 parts by weight or less, or 4 parts by weight or less. If too much of the unsaturated carboxylic acid-based monomer is used, the aging peel strength may increase even when stored for a long time at high temperature, and if too little is used, the adhesive strength may decrease.

d) vinyl monomer

Next, in the emulsion polymerization for preparing the latex particles, a vinyl-based monomer may be used, and this may be referred to as a fourth monomer. Accordingly, the latex particle may include a repeating unit derived from a vinyl-based monomer, and this may be referred to as a fourth repeating unit.

The vinyl-based monomer imparts elasticity to the emulsified polymer particles, controls the glass transition temperature, and improves the balance between adhesive force, peel force and retention force.

The vinyl-based monomer is a vinyl ester-based monomer containing an alkyl group having 1 to 5 carbon atoms; And at least one selected from the group consisting of aromatic vinyl-based monomers.

The vinyl ester monomer includes a vinyl group at one end of the molecule and an alkyl group having 1 to 5 carbon atoms at the opposite end thereof, and specifically, for example, vinyl acetate , Vinyl propanoate, vinyl butanoate, and one or more selected from the group consisting of vinyl pentanoate.

In addition, the aromatic vinyl-based monomer is selected from the group consisting of styrene, methylstyrene, methylstyrene, butylstyrene, chlorostyrene, vinylbenzoic acid, methyl vinylbenzoate, vinylnaphthalene, chloromethylstyrene, hydroxymethylstyrene, and divinylbenzene. One or more can be mentioned.

The vinyl-based monomers may be used alone or in combination of two or more.

Although the present invention is not limited thereto, for example, the vinyl-based monomer is 1 part by weight or more, or 1.5 parts by weight or more, or 2 parts by weight or more, and 5 parts by weight or less, or It may be included in 4.5 parts by weight or less, or 4 parts by weight or less. If too much of the vinyl-based monomer is used, stability may be deteriorated, and if too little is used, a problem of lowering adhesion may occur.

e) internal crosslinking agent

The emulsion polymer particles of the present invention are obtained by emulsion polymerization of a polyalkylene glycol diacrylate-based crosslinking agent with a mixture of the aforementioned monomers and an internal crosslinking agent. The internal crosslinking agent is a component added to the reaction mixture in order to reinforce cohesive force most fundamentally, and has a high shear characteristic, and serves to connect long polymer chains to obtain an excellent effect of enhancing the net effect. The most important feature of the shear is that the cohesive force between the polymers is large, and this helps the dried latex to be firmly fixed without being broken off easily.

The polyalkylene glycol diacrylate-based crosslinking agent is 0.05 parts by weight or more, or 0.1 parts by weight or more, or 0.15 parts by weight or more, 0.5 parts by weight or less, or 0.4 parts by weight or less, or It may be included in an amount of 0.3 parts by weight or less. If too little of the polyalkylene glycol diacrylate-based crosslinking agent is used, adhesion may be reduced due to a decrease in the degree of crosslinking, and if too much is used, the degree of crosslinking is excessively increased, resulting in deterioration of polymerization stability and agglomeration of latex particles. I can.

On the other hand, according to an embodiment of the present invention, the monomer mixture may contain other additives without special limitation within a range that does not deteriorate the effect of the invention in addition to the above-described components. As an example, the additive may include an external crosslinking agent, a buffering agent, a wetting agent, a neutralizing agent, a polymerization terminator, and a tackifier, and one or two or more of them may be additionally included.

As the external crosslinking agent, diacetone acrylamide (DAAM) and adipic acid dihydride (ADH) may be used to additionally be designed to cause a crosslinking reaction from the outside. The external crosslinking agent may be added later at the terminal portion of the polymerization process and may serve as an intercross linker connecting the polymer and the polymer. The external crosslinking agent may be used in an amount of about 1.2 parts by weight or less, or about 0 to 1.2 parts by weight, or about 0.7 parts by weight or less, or 0.01 to 0.7 parts by weight, based on 100 parts by weight of the monomer mixture.

Examples of the buffer may include sodium bicarbonate, sodium carbonate, sodium phosphate, sodium sulfate, sodium chloride, and the like, but are not limited thereto. In addition, these may be used alone or in combination of two or more. The buffering agent may play a role in controlling pH and imparting polymerization stability in the polymerization reaction. The buffering agent may be used in an amount of about 1.0 part by weight or less, or 0 to 1.0 part by weight, or 0.5 part by weight or less, or 0.1 to 0.5 parts by weight, based on 100 parts by weight of the monomer mixture.

The wetting agent serves as an emulsifier for lowering the surface tension for coating properties, and its content can be used within a range well known in the art. As an example, as the wetting agent, a dioctyl sodium sulfosuccinate (DOSS)-based compound may be mentioned. The humectant may be used in an amount of about 1.0 part by weight or less, or 0 to 1.5 parts by weight, or 1.2 parts by weight or less, or 0.1 to 1.2 parts by weight, based on 100 parts by weight of the monomer mixture.

Examples of the neutralizing agent include NaOH, NH ₄ OH, and KOH. The neutralizing agent may be used in an amount of about 1.0 parts by weight or less, or 0 to 1.0 parts by weight, or 0.5 parts by weight or less, or 0.1 to 0.5 parts by weight, based on the monomer mixture.

In addition, the polymerization terminator is added to suppress side reactions in which the radicals remaining after the preparation of the latex, that is, the acrylic emulsion resin and the residual monomers react, and is an additive that removes the radicals to eliminate additional reactions. Such polymerization terminators are also referred to as radical inhibitors. It is also simply referred to as a ban. A substance that quickly reacts with a polymerization initiator or a radical as a monomer to lose and stabilize the radicality to stop the polymerization reaction, and if a monomer with radical polymerization is left in a pure state, it is naturally polymerized, so it is often added for preservation. It is also called an inhibitor or polymerization inhibitor. However, even if an inhibitor is added, polymerization starts spontaneously because it is consumed in the meantime after a certain period (induction period) has elapsed. Representative inhibitors are hydrokinone and p-tert-pticatechol. In addition, there are benzoquinone, chromanyl, m-dinitrobenzene, nitrobenzene P-phenylziamine sulfur, etc. These are substances that easily react with radicals and stabilize. In addition, diphenylpicryhydrazyl-P-pulolphenylamine and tri-P-nitrophenylmethyl, which are themselves stable radicals, are also used as inhibitors. Preferably, NaNO ₂ may be used as the polymerization terminator. The polymerization terminator may be used in an amount of about 1.0 part by weight or less, or 0 to 1.0 part by weight, or 0.5 part by weight or less, or 0.1 to 0.5 parts by weight, based on the monomer mixture.

In addition, the tackifier is added to the role of lowering the surface tension by additionally adding an emulsifier. In this case, a dioctyl sodium sulfosuccinate (DOSS)-based compound can be used to significantly lower the surface tension by using a small amount. The tackifier may be used in an amount of about 1.5 parts by weight or less, or 0 to 1.5 parts by weight, or 1.2 parts by weight or less, or 0.8 parts by weight or less, or 0.1 to 0.6 parts by weight, based on 100 parts by weight of the monomer mixture.

On the other hand, the monomer mixture serves as a chain transfer agent (CTA) during the polymerization reaction of the acrylic emulsion resin, and specifically, may further include a molecular weight modifier that is attached to the end of the molecule and serves to transfer radicals to other places. have.

On the other hand, in order to smoothly perform the polymerization process, the order in which each component is added may be performed differently. For example, at the beginning of the polymerization process, it may be desirable to first stir and dissolve additives such as a surfactant and a buffer in water, and then add a monomer mixture such as a monomer, an emulsifier, and an internal crosslinking agent while stirring.

According to an embodiment of the present invention, the polymerization composition may further include an aqueous solvent such as water in addition to the above-described components.

At this time, the aqueous solvent, in terms of stability and viscosity control of the latex particles, may be used in an amount of about 10 to about 1.000 parts by weight, based on 100 parts by weight of the monomer mixture, and, for example, based on the total amount of the composition, the total It may be used so that the total solid content (TSC) is adjusted to about 10 to about 60% by weight.

Emulsified polymer particles, that is, latex particles included in the aqueous pressure-sensitive adhesive composition according to an embodiment of the present invention may be prepared by a generally known emulsion polymerization method.

Specifically, the method for preparing the aqueous pressure-sensitive adhesive composition includes a (meth)acrylic acid ester-based monomer, a vinyl-based monomer, and a (meth)acrylic acid-based monomer including an alkyl group having 1 to 14 carbon atoms; Preparing a monomer mixture containing a (meth)acrylic ester-based monomer containing a hydroxy group; The step of preparing a polymerization composition by adding an emulsifier to the monomer mixture: emulsion polymerization of the polymerization composition in the presence of a polymerization initiator.

The emulsifier is used for initial particle generation during polymerization of the monomer mixture, control of the size of the generated particles, and stability of the particles. The emulsifier may include any one or more emulsifiers of a nonionic emulsifier and an anionic emulsifier.

This emulsifier is a material having both hydrophilic and hydrophobic groups, and forms a micelle structure in the emulsion polymerization process, and allows polymerization of each monomer within the micelle structure.

Emulsifiers generally used in emulsion polymerization can be divided into anionic emulsifiers, cationic emulsifiers, and nonionic emulsifiers, and in terms of polymerization stability in emulsion polymerization, two or more types are mixed and used.

Specifically, in the case of the anionic emulsifier, at least one selected from the group consisting of sodium alkyldiphenyloxide disulfonate compounds, sodium polyoxyethylene alkyl ether sulfate compounds, and sodium dialkyl sulfosuccinate compounds It may include.

In addition, the nonionic emulsifier includes a dialkylene glycol alkyl ether compound including an alkylene group having 2 to 5 carbon atoms and an alkyl group having 5 to 15 carbon atoms; A dialkylene glycol alkyl ester compound containing an alkylene group having 2 to 5 carbon atoms and an alkyl group having 5 to 15 carbon atoms; And it may be one or more selected from the group consisting of a dialkylene glycol alkyl amine-based compound, including an alkylene group having 2 to 5 carbon atoms and an alkyl group having 5 to 15 carbon atoms, which may be used alone or in combination of two or more. It may be more effective when using a mixture of an anionic emulsifier and a nonionic emulsifier, but the present invention is not necessarily limited to the type of the emulsifier.

In addition, the emulsifier may be used in an amount of, for example, about 0.01 to about 1 part by weight, or about 0.01 to about 0.5 parts by weight, based on 100 parts by weight of the monomer mixture.

If too little emulsifier is used, the size of the latex particles to be produced increases and the polymerization stability may be deteriorated.If too much emulsifier is used, the size of the latex particles to be prepared becomes too small, or the emulsion pressure-sensitive adhesive There may be a problem in that the adhesive properties are deteriorated.

As the polymerization initiator, a water-soluble polymerization initiator such as ammonium or alkali metal persulfate, for example, ammonium persulfate, hydrogen peroxide, peroxide, or hydroxyl peroxide may be used. At this time, the content of the polymerization initiator is about 1.0 parts by weight or less, or 0 to 1.0 parts by weight, or 0.6 parts by weight or less, or 0.01 to 0.6 parts by weight, or 0.45 parts by weight or less, or 0.1 to 0.45 parts by weight based on 100 parts by weight of the monomer mixture. It may be used in parts by weight, or 0.4 parts by weight or less, or 0.5 to 0.4 parts by weight.

In addition, the polymerization initiator may be divided into one or more times during the polymerization step of the monomer mixture and appropriately divided within the above-described range. However, when the polymerization initiator is added at the beginning of polymerization before the emulsifier is added to the monomer mixture, about 0.2 parts by weight or less or about 0 to 0.2 parts by weight to minimize the possibility that a residual problem may occur. Parts, or about 0.1 parts by weight or less, or about 0 to 0.1 parts by weight, about 0.05 parts by weight or less, or about 0 to 0.05 parts by weight or less. Preferably, the polymerization initiator is added simultaneously with the pre-emulsion, and may be dividedly or continuously added over a period of up to about 70% of the total polymerization time.

In addition, an activator may be further included to accelerate the reaction initiation of the peroxide together with the polymerization initiator, and such activators include sodium formaldehyde sulfoxylate, sodium ethylenediamine tetraacetate, ferrous sulfate, and dextrose. One or more selected from the group consisting of may be used.

In the emulsion polymerization, the polymerization temperature and polymerization time may be appropriately determined depending on the case. For example, the emulsion polymerization may be performed at a temperature of about 70 to 90° C. for about 3 hours to about 6 hours. In addition, when considering the physical properties of the pressure-sensitive adhesive, the polymerization temperature may be about 75 to about 85°C.

The acrylic emulsion pressure-sensitive adhesive composition prepared by the above-described method has ^{a viscoelasticity ratio (Tan delta) measured at a temperature of 25° C. in the range of 5.0*10 -2} to 1.0*10 ² rad/sec from 0.5 to 0.8 in the entire frequency range. It has the characteristic of being. The viscoelastic ratio is the ratio (G"/G') of the loss elastic modulus (G") to the storage elastic modulus (G'), and a value greater than 1 means that the viscosity is stronger than the elasticity.

As the viscosity of the acrylic emulsion pressure-sensitive adhesive composition increases, adhesion increases due to an increase in adhesion, whereas a decrease in cohesion may reduce retention and cause bleeding. Conversely, as the viscosity of the acrylic emulsion pressure-sensitive adhesive composition becomes weaker and the elasticity becomes stronger, the cohesion increases, and the bonding between the polymer chains inside the pressure-sensitive adhesive composition is strengthened, but the overall adhesive properties may be deteriorated due to a decrease in adhesion. As described above, the acrylic emulsion pressure-sensitive adhesive composition of the present invention may exhibit a range of viscoelasticity in the above range by controlling the type and content of the monomers and the internal crosslinking agent contained in the emulsion polymer particles.

The viscoelastic ratio of the acrylic emulsion pressure-sensitive adhesive composition basically increases as the glass transition temperature of the composition decreases, the higher the adhesive strength and the increase in the loss modulus, resulting in an increase in the viscoelastic ratio. On the other hand, as the glass transition temperature of the composition increases, the cohesive strength increases. And the storage modulus increases, and as a result, the viscoelastic ratio tends to decrease. Therefore, in general, the higher the viscoelasticity ratio, the higher the adhesive properties at low temperature, whereas the adhesive properties at room temperature decrease. Conversely, the smaller the viscoelastic ratio, the lower the adhesive properties at low temperature, and the adhesive properties at room temperature tend to be improved. However, the viscoelastic ratio of the acrylic emulsion pressure-sensitive adhesive composition is not only dependent on the glass transition temperature, but is determined complexly by the particle size, molecular weight, and crosslinking degree of the composition, and has a certain viscoelastic ratio through an appropriate balance thereof.

On the other hand, the relationship between the range of the viscoelastic ratio of the acrylic emulsion pressure-sensitive adhesive composition and the adhesive properties according to temperature is unknown, and the viscosity and elasticity of the emulsified polymer particles are properly balanced by the inventors of the present invention, as described above. It was confirmed that the acrylic emulsion pressure-sensitive adhesive composition can exhibit excellent adhesive properties in a wide temperature range over room temperature and low temperature when the ratio is in a certain range.

The acrylic emulsion pressure-sensitive adhesive composition according to an embodiment of the present invention has a viscoelastic ratio (Tan delta, G"/G') of 0.5 measured ^{at a temperature of 25°C and in the range of 5.0*10 -2} to 1.0*10 ^{2 rad/sec.} Or more, or 0.51 or more, or 0.52 or more, or 0.53 or more, 0.8 or less, or 0.79 or less, or 0.78 or less, or 0.77 or less The viscoelastic ratio of the acrylic emulsion pressure-sensitive adhesive composition of the present invention is 5.0*10 ^-2 to 1.0* The above-described range is satisfied within all frequency ranges of ^{10 2 rad/sec.}

In addition, the acrylic emulsion pressure-sensitive adhesive composition has a storage elastic modulus (G') ^{at a temperature of 25° C., 5.0*10 -2 rad/sec, from 2.0*10 3} Pa or more to 1.5*10 ⁴ Pa or less, or 4.0*10 ³ Pa or more and 1.2*10 ⁴ Pa or less, and the storage elastic modulus (G') at a temperature of 25° C., 1.0*10 ^{2 rad/sec is 5.0*10 4} Pa or more and 1.5*10 ⁵ Pa or less, or 7.0 *10 ⁴ Pa or more and 1.3*10 ⁵ Pa or less.

In addition, the acrylic emulsion pressure-sensitive adhesive composition has a loss modulus (G") ^{at a temperature of 25°C and 5.0*10 -2 rad/sec from 1.0*10 3} Pa to 1.0*10 ⁴ Pa or less, or 3.0*10 ³ Pa or more and 8.0*10 ³ Pa or less, and the loss modulus (G") at a temperature of 25° C., 1.0*10 ^{2 rad/sec is 2.0*10 4} Pa or more and 1.0*10 ⁵ Pa or less, or 4.0 *10 ⁴ Pa or more and 8.0*10 ⁴ Pa or less.

The acrylic emulsion pressure-sensitive adhesive composition has an initial adhesive strength (loop tack) of 10 N/inch or more, or 11 N/inch or more, or 12 N/inch or more, at room temperature (22±2° C.) and SUS substrate, and 16 It may be N/inch or less, or 15 N/inch or less, or 14 N/inch or less. Here, at room temperature (22±2°C), and the initial adhesive strength (loop tack) on the SUS substrate, the test method FINAT TEST METHOD NO. It can be measured according to 9. For example, a specimen is made into a loop shape and fixed to a clamp, and the specimen is attached to a stainless steel surface (SUS 304) at a constant speed. After about 5 seconds, a measurement speed of about 300 mm/min is applied and the maximum force when separating in the opposite direction is measured by the loop tack peeling force.

The acrylic emulsion pressure-sensitive adhesive composition has an initial adhesive strength (loop tack) of 6 N/inch or more, or 6.5 N/inch or more, or 7 N/inch or more, at room temperature (22±2° C.) and a paper substrate, and 10 N /inch or less, or 9 N/inch or less, or 8 N/inch or less. Here, room temperature (22±2°C), and the initial adhesive strength (loop tack) on the paper substrate were determined by the test method FINAT TEST METHOD NO. It can be measured according to 9. For example, a specimen is made into a loop shape and fixed to a clamp, and the specimen is attached to a paper substrate at a constant speed. After about 5 seconds, a measurement speed of about 300 mm/min is applied and the maximum force when separating in the opposite direction is measured by the loop tack peeling force.

The acrylic emulsion pressure-sensitive adhesive composition has a low temperature (-10±2° C.), and an initial adhesive strength (loop tack) on a paper substrate of 5.5 N/inch or more, or 6 N/inch or more, or 6.5 N/inch or more, and 10 N/inch or less, or 9.5 N/inch or less, or 9 N/inch or less. Here, the low temperature (-10±2° C.), and the initial adhesive strength (loop tack) on the paper substrate were determined by the test method FINAT TEST METHOD NO. It can be measured according to 9. For example, a specimen is made into a loop shape and fixed to a clamp, and the specimen is attached to a paper substrate at a constant speed. After about 5 seconds, a measurement speed of about 300 mm/min is applied and the maximum force when separating in the opposite direction is measured by the loop tack peeling force.

The acrylic emulsion pressure-sensitive adhesive composition also has a peel strength (90° peel) of 7 N/inch or more, or 7.5 N/inch or more, or 8 N/inch or more, and 10 N/inch or less, or 9 N/inch or less, Alternatively, it may be less than or equal to 9.5 N/inch. Here, peel strength (peel) is the test method FINAT TEST METHOD NO. It can be measured according to 2. As an example, an acrylic emulsion pressure-sensitive adhesive specimen is reciprocated once or more with a 2 kg roller at a speed of about 300 mm/min, attached on a stainless steel surface (SUS 304), aged at room temperature for about 20 minutes, and then aged at room temperature for about 20 minutes. It is measured while peeling at 90 degrees (90°) at a rate of about 300 mm/min using.

The acrylic emulsion pressure-sensitive adhesive composition also has a retention force (shear) of 30 to 100 minutes/0.5inch·0.5kg, or about 30 to 60 minutes/0.5inch·0.5kg, or about 35 to 50 minutes/0.5inch·0.5kg I can. Here, the holding force (shear) can be measured by a holding power test (Shear test) method. For example, by preparing a bright stainless steel plate (Bright SUS: glossy and more slippery), the adhesive specimen is reciprocated twice with a roller of about 2 kg and attached to the adherend surface, The holding power is measured after 20 minutes of the dwell time. After applying a fixed load of about 0.5 kg to the bottom of the sample, measure the time the adhesive sample fell.

The acrylic emulsion pressure-sensitive adhesive composition prepared according to the manufacturing method of the present invention described above is, but is not limited to, a pressure-sensitive adhesive for paper, and more specifically, may be applied to an adherend such as a delivery box, a cardboard box, an egg box, and the like.

Hereinafter, the action and effect of the invention will be described in more detail through specific examples of the invention. However, this is presented as an example of the invention, and the scope of the invention is not limited to any meaning by this.

<Example>

Example 1

After preparing a pre-emulsion by mixing a monomer mixture, an internal crosslinking agent, and water as follows, the pre-emulsion was emulsion-polymerized to prepare an acrylic emulsion resin.

First, in a 3 L glass reactor equipped with a thermometer, stirrer, dropping funnel, nitrogen inlet pipe and reflux condenser, about 208.2 g of water and sodium polyoxyethylene lauryl ether sulfate as the first surfactant. About 2.1 g was added and the inside of the reactor was replaced with nitrogen while stirring, and then the temperature was raised to about 80° C. under a nitrogen atmosphere, and this was maintained for about 60 minutes.

Separately, in a beaker about 825.2 g of 2-ethylhexyl acrylate (2-EHA), about 13.6 g of methyl methacrylate (MMA), about 27.3 g of styrene (SM), about 28.1 g of acrylic acid (AA), and 2-hydroxy After about 13.6 g of ethyl acrylate (HEA) was added, 907.8 g of a monomer mixture mixed for about 30 minutes was prepared. In addition, about 1.8 g of polyethylene glycol diacrylate (M280) as an internal crosslinking agent in the monomer mixture, about 26% by weight of sodium polyoxyethylene lauryl ether sulfate as a first surfactant, about 34.6 g, A solution consisting of about 3.9 g of Alkyldiphenyloxide Disulfonate as a second surfactant, about 1.8 g of sodium carbonate as a buffer, about 1.8 g of sodium methylallyl sulfonate as a third surfactant, and about 231.3 g of water Was added, and mixed with a stirrer to prepare a cloudy pre-emulsion.

About 10 g of about 5% by weight ammonium persulfate was added to a 3 L glass reactor containing the surfactant, followed by stirring for about 10 minutes to dissolve. Then, the pre-emulsion prepared above and about 150 g of about 5% by weight ammonium persulfate aqueous solution were equally continuously added to the glass reactor for about 5 hours, and then maintained at about 80° C., and this temperature was maintained for about 1 hour. After maintaining, about 10% by weight aqueous ammonia solution was added to adjust the pH to about 7 to about 8.5. Then, about 1 part by weight of dioctyl sodium sulfosuccinate was added as a wetting agent that acts as an emulsifier that lowers the surface tension for coating properties, based on 100 parts by weight of the acrylic emulsion resin, After cooling to room temperature, an acrylic emulsion resin for pressure-sensitive adhesive was prepared.

Examples 2 to 3 and Comparative Examples 1 to 2

In Example 1, an acrylic pressure-sensitive adhesive composition was prepared by varying the composition of the monomer mixture.

Comparative Example 3

An acrylic pressure-sensitive adhesive composition was prepared in the same manner as in Example 1 of KR Publication No. 2016-0019652.

Comparative Example 4

An acrylic pressure-sensitive adhesive composition was prepared in the same manner as in Example 1 of KR Patent Publication No. 2016-0050979.

The compositions of the monomer mixtures of Examples 1 to 3 and Comparative Examples 1 to 4 are summarized in Table 1 below.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Monomer
(weight%) 2-EHA 91.5 90.5 89 85.0 94 92 56 BA - - - 9.0 - - 20 MMA 1.5 2 2.5 1.5 1.5 2.2 10 SM 3 2.5 2 2.5 2.5 - - 2-HEA 1.5 2.5 3 - - 2.8 3 AA 2.5 2.5 2 2.0 2.0 One One VAc - - 1.5 2 10 Sum 100 100 100 100 100 100 100 M280
(Parts by weight based on 100 parts by weight of the monomer mixture) M280 0.2 0.2 0.2 0.2 0.2 0.15 0.15 n-DDM (parts by weight based on 100 parts by weight of the monomer mixture) - - - - - - 0.05 0.05

BA: butyl acrylate

2-EHA: 2-ethylhexylacrylate

SM: styrene

MMA: methyl methacrylate

AA: acrylic acid

VAc: vinyl acetate

M280: Polyethylene glycol 400 Diacrylate (PEGDA)

n-DDM: Normal dodecyl mercaptan

Measurement of storage modulus, loss modulus, and viscoelastic ratio

The pressure-sensitive adhesive compositions prepared in Examples and Comparative Examples were coated between the release films, and then cut into a size of 10 cm × 10 m, and the release film on one side was removed and then laminated to make the thickness of about 1 mm. Subsequently, the laminate is cut into a circle having a diameter of 8 mm, compressed using glass, and then left overnight to improve wetting at the interface between each layer to remove air bubbles generated during lamination. To prepare a sample. Subsequently, the sample was placed on a parallel plate, the gap was adjusted, the zero point of Normal & Torque was adjusted, and after confirming the stabilization of the normal force, the storage modulus and loss modulus were measured.

In addition, the ratio (G"/G') of the loss modulus (G") to the storage modulus (G') was calculated as the viscoelasticity ratio (Tan delta).

<Measurement equipment and measurement conditions>

* Measuring instrument: ARES-RDA with forced convection oven, TA Instruments Inc.

* Measuring conditions:

geometry: 8 mm parallel plate

Thickness: approx. 1 mm

Test type: dynamic strain frequency sweep

Strain = 10.0 [%], Temperature: 25 ℃

Initial frequency: 5.0*10 ^-2 rad/s, Final frequency: 1.0*10 ² rad/s

The storage elastic modulus, loss elastic modulus, and viscoelasticity ratio measured by the above method are shown in Table 2 below. In addition, a graph showing the viscoelastic ratio according to the frequency of the pressure-sensitive adhesive compositions according to Examples 1 to 3 and Comparative Examples 1 to 4 is shown in FIG. 1.

Storage modulus of elasticity (G') Loss modulus (G") Viscoelasticity ratio (G"/G') frequency:
5.0*10 ^-2 rad/sec
(Unit: Pa) frequency:
1.0*10 ² rad/sec
(Unit: Pa) frequency:
5.0*10 ^-2 rad/sec
(Unit: Pa) frequency:
1.0*10 ² rad/sec
(Unit: Pa) frequency:
5.0*10 ^-2 rad/sec
frequency:
1.0*10 ² rad/sec
Example 1 5,905 74,354 3,299 50,169 0.56 0.67 Example 2 5,921 86,601 3,196 65,499 0.54 0.76 Example 3 11,434 110,891 6,120 69,376 0.54 0.62 Comparative Example 1 13,148 113,197 6,093 67,808 0.46 0.60 Comparative Example 2 16,440 103,131 7,170 54,030 0.44 0.52 Comparative Example 3 7,473 84,786 3,166 56,705 0.42 0.67 Comparative Example 4 15,375 100,900 7,076 56,699 0.46 0.56

Referring to Tables 1 to 1, the pressure-sensitive adhesive composition of the examples is a viscoelastic ratio (Tan delta, G"/G') measured ^{at a temperature of 25° C. and in the range of 5.0*10 -2} to 1.0*10 ^{2 rad/sec} Satisfies 0.5 to 0.8 in the entire frequency range.

<Experimental Example>

Preparation of adhesive specimen coated with adhesive

The pressure-sensitive adhesive compositions prepared in Examples and Comparative Examples were applied on a silicone-coated release paper, respectively, and dried in an oven at about 120° C. for about 1 minute so that the pressure-sensitive adhesive layer had a thickness of about 20 μm. This was laminated with an art paper film to make a paper label and cut into a size of 1 inch x 150 mm to prepare a paper label specimen.

The adhesive properties of the specimens using the acrylic emulsion adhesive composition prepared from the above Examples and Comparative Examples were tested in the following manner. The results are shown in Table 3 below.

1) Initial adhesion (Loop tack) test (N/inch): room temperature, SUS base

Preparing Specimen for Loop

-Sample size: 25mm X 150mm

-Substrate: Stainless steel plate

-Measurement conditions: 22±2℃, 50±5%RH

-Measurement method: The specimen was made into a loop shape and fixed to the clamp, and the specimen was attached to a stainless steel plate at a constant speed. After about 5 seconds, the force corresponding to the maximum value when separating in the opposite direction by applying a measurement speed of about 300 mm/min was measured by the loop tack peeling force.

2) Initial adhesion (Loop tack) test (N/inch): room temperature, paper substrate

The test was performed in the same manner as in the above 1) initial adhesion test (room temperature, SUS base), except that corrugated board was used as the adherend.

3) Initial adhesion (Loop tack) test (N/inch): low temperature, paper substrate

Preparing Specimen for Loop

-Sample size: 25mm X 150mm

-Substrate: Corrugated cardboard

-Measurement conditions: -10±2℃, 50±5%RH

-Measurement method: The specimen in the low-temperature chamber was made into a loop shape and fixed to the clamp, and after adjusting the temperature and humidity of the chamber to the above measurement conditions, the specimen was attached to the cardboard at a constant speed. After about 5 seconds, the force corresponding to the maximum value when separating in the opposite direction by applying a measurement speed of about 300 mm/min was measured by the loop tack peeling force.

4) Peel force (90°peel) test (N/inch)

Test method FINAT TEST METHOD NO. According to 2, the acrylic emulsion adhesive specimen was reciprocated once with a 2 kg roller at a speed of about 300 mm/min, attached on a stainless steel plate, aged at room temperature for about 20 minutes, and then the TA Texture Analyzer instrument was used. It was measured while peeling at 90° (90°) at a rate of about 300 mm/min.

5) Shear

The Holding Power test (Shear test) was conducted in the following way.

-Sample size: 25mm X 25mm

-Substrate: Bright Stainless steel plate (Bright SUS: shiny and more slippery)

-Measurement conditions: 22±2℃, 50±5%RH

-Measurement method: The specimen was reciprocated once with a roller of about 2 kg and attached to the adherend, and then the holding force was measured without dwell time (measurement speed 300 mm/min).

After applying a fixed load of about 1 kg to the lower end of the sample, the time the pressure-sensitive adhesive sample fell was measured.

Loop tack
(N/inch) 90° peel
(N/inch) Shear
(min) SUS (room temperature) Paper (room temperature) Paper (low temperature) SUS 0.5in*0.5in, 0.5kg Example 1 11.5 7.1 6.2 8.1 38 Example 2 12.6 7.9 8.1 8.9 42 Example 3 12.3 8.1 7.8 7.9 35 Comparative Example 1 13.7 7.5 3.2 7.3 21 Comparative Example 2 9.7 5.8 5.3 6.1 25 Comparative Example 3 7.5 4.3 6.1 4.9 100 Comparative Example 4 10.2 9.4 3.5 9.2 430

Referring to Table 2, the acrylic emulsion pressure-sensitive adhesive composition of the embodiment of the present invention has a viscoelastic ratio (Tan delta, G"/G') measured ^{at a temperature of 25°C and in the range of 5.0*10 -2} to 1.0*10 ^{2 rad/sec.} Satisfying 0.5 to 0.8, the viscosity and elasticity were balanced, and exhibited excellent adhesive properties both at room temperature and in a wide temperature range at low temperature.

On the other hand, Comparative Examples 1 and 4 had relatively excellent adhesive strength at room temperature, but low adhesive strength at low temperatures, whereas Comparative Examples 2 and 3 had relatively excellent adhesive strength at low temperatures, but low adhesive strength at room temperature. Accordingly, it can be seen that it is difficult to satisfy both the adhesive strength at room temperature and low temperature. On the other hand, it can be seen that the acrylic emulsion pressure-sensitive adhesive composition of the present invention achieves this by controlling the viscoelasticity ratio within a certain range.

Claims (12)

Alkyl (meth)acrylate-based monomers; Hydroxy group alkyl (meth)acrylate-based monomers; Unsaturated carboxylic acid-based monomers; And by emulsion polymerization of a monomer mixture containing a vinyl-based monomer and a polyalkylene glycol diacrylate-based crosslinking agent,
Containing emulsified polymer particles,
The viscoelastic ratio (Tan delta, G"/G') measured in a temperature of 25° C. in the range of 5.0*10 ^-2 to 1.0*10 ^{2 rad/sec is 0.5 to 0.8,}
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 1,
The storage elastic modulus (G') at a temperature of 25°C, 5.0*10 ^{-2 rad/sec is 2.0*10 3} Pa or more and 1.0*10 ⁴ Pa or less,
The storage elastic modulus (G') at a temperature of 25°C, 1.0*10 ^{2 rad/sec is 5.0*10 4} Pa or more and 1.5*10 ⁵ Pa or less,
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 1,
The loss modulus (G") at a temperature of 25°C, 5.0*10 ^{-2 rad/sec is 1.0*10 3} Pa or more and 1.0*10 ⁴ Pa or less,
The loss modulus (G") at a temperature of 25° C., 1.0*10 ^{2 rad/sec is 2.0*10 4} Pa or more and 1.0*10 ⁵ Pa or less,
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 1,
The alkyl (meth) acrylate monomers are methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl ( Meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, dodecyl (meth)acrylate, isobornyl (meth)acrylate, and lauryl (meth)acrylate Including at least one selected from the group consisting of,
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 1,
The hydroxy group alkyl (meth) acrylate-based monomer includes at least one selected from the group consisting of hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and hydroxybutyl (meth)acrylate,
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 1,
The unsaturated carboxylic acid monomers include acrylic acid, fumaric acid, maleic acid, itaconic acid, citraconic acid, mesaconic acid, and text. Including one or more selected from the group consisting of rutaconic acid, and allylmalonic acid,
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 1,
The vinyl-based monomer,
A vinyl ester-based monomer containing an alkyl group having 1 to 5 carbon atoms; And containing at least one selected from the group consisting of an aromatic vinyl-based monomer,
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 7,
The vinyl ester-based monomer includes at least one selected from the group consisting of vinyl acetate, vinyl propanoate, vinyl butanoate, and vinyl pentanoate,
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 7,
The aromatic vinyl monomer is one selected from the group consisting of styrene, methylstyrene, methylstyrene, butylstyrene, chlorostyrene, vinylbenzoic acid, methyl vinylbenzoate, vinylnaphthalene, chloromethylstyrene, hydroxymethylstyrene, and divinylbenzene. Including the above,
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 1,
Based on 100 parts by weight of the monomer mixture,
85 to 90 parts by weight of the alkyl (meth)acrylate-based monomer;
1 to 5 parts by weight of the hydroxy group alkyl (meth)acrylate-based monomer;
1 to 5 parts by weight of the unsaturated carboxylic acid monomer;
1 to 5 parts by weight of the vinyl-based monomer; And
Containing the polyalkylene glycol diacrylate-based crosslinking agent in an amount of 0.05 to 0.5 parts by weight,
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 10,
The weight ratio between each of the two types of monomers selected from the hydroxy group alkyl (meth) acrylate monomer, the unsaturated carboxylic acid monomer, and the vinyl monomer is 0.5 to 2,
Acrylic emulsion pressure-sensitive adhesive composition.
The method of claim 1,
Room temperature (22±2°C), and the initial adhesive strength (loop tack) on the SUS substrate is 10 to 16 N/inch,
Room temperature (22±2°C), and the initial adhesive strength (loop tack) on the paper substrate is 6 to 10 N/inch,
Low temperature (-10±2° C.), and an initial adhesive force (loop tack) on a paper substrate of 5.5 to 10 N/inch,
Acrylic emulsion pressure-sensitive adhesive composition.

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