KR101109298B1 - Acrylic Adhesive, A Method For Manufacturing Thereof, And Adhesive Sheet Comprising The Same - Google Patents

Abstract

The present invention relates to an aqueous acrylic pressure-sensitive adhesive, a method for manufacturing the same, and a pressure-sensitive adhesive sheet including the same. According to the present invention, it is possible to provide an aqueous acrylic pressure-sensitive adhesive having excellent water resistance while applying adhesive strength and storage stability of an oil-based pressure-sensitive adhesive. In this case, it is possible to provide a pressure-sensitive adhesive sheet having excellent workability by preventing the migration of the surfactant to the surface of the prepared pressure-sensitive adhesive sheet.

Acrylic emulsion, water-based adhesive, adhesive sheet, workability

Description

Acrylic Adhesive, A Method For Manufacturing Thereof, And Adhesive Sheet Comprising The Same}

The present invention relates to an aqueous acrylic pressure-sensitive adhesive, a manufacturing method and a pressure-sensitive adhesive sheet comprising the same, and more particularly, an aqueous acrylic pressure-sensitive adhesive and a manufacturing method having excellent water resistance while maintaining the adhesive strength and storage stability of the oil pressure-sensitive adhesive and the surface of the pressure-sensitive adhesive sheet by applying the same It is related with the adhesive sheet which can prevent the phenomenon which a surfactant transfers.

Recently, the use of surface finishes in the form of stickers, such as interior / exterior materials, interior materials and advertising materials of buildings with adhesives has been increasing. As the pressure-sensitive adhesive, the oil-based pressure-sensitive adhesive is excellent in adhesive strength, but it contains organic solvents, so there is a problem in that a large amount of substances harmful to the environment and the human body are discharged. It is environmentally friendly and does not emit harmful substances to the human body, and there is an advantage of almost no transfer of the adhesive when removed after use. However, the adhesive strength is somewhat lower than that of the oil-based adhesive, and in particular, the adhesive properties due to aging are greatly reduced. .

On the other hand, since the water-based pressure-sensitive adhesive synthesized by the conventional emulsion polymerization adds hydrophilic substances such as surfactants, buffers, and water-soluble initiators in addition to the monomers, when the pressure-sensitive adhesive sheet is exposed to water, whitening occurs, and thus it does not adhere to the substrate. Will occur. The cause of this problem is that the added hydrophilic material absorbs water. Since such a hydrophilic material is necessary for the stability of the latex, it is difficult to improve the water resistance of the water-based adhesive.

In particular, the surfactant imparting stability of the resin particles is present on the surface of the adhesive surface after coating to reduce adhesion to the adherend and to act as a substrate that absorbs moisture when contacted with water, causing adhesive strength and whitening. In coating, the cohesion may be lowered by interfering with the latex particles in the pressure-sensitive adhesive.

In addition, a wetting agent that lowers the surface tension of the pressure-sensitive adhesive to improve the wettability on the surface of the silicone release paper is also a kind of surfactant, which causes problems similar to those of the surfactant. Specifically, the relationship between the adhesive properties and the rheological properties of the adhesive resin may be confirmed depending on the presence of the surfactant, and the water resistance may be affected by the molecular weight of the surfactant and the salt form of the surfactant. Physical property results can be found in J. Adhesion, 1999, Vol. 70, pp. 179-195. This prior art document demonstrates that the water resistance of the adhesive resin is advantageous as the molecular weight of the surfactant is higher and that the surfactant of the ammonium salt is more favorable to the water resistance of the adhesive resin than the sodium salt.

As a related prior art, US Patent Publication No. 2005/0250887 discloses an example of applying a reactive surfactant to improve water resistance, and US Patent Publication No. 2008/0249239 A discloses a reactive allylamine salt form in an acrylic monomer composition. An example of applying a reactive surfactant is disclosed. In addition, US Pat. No. 6,121,355 introduces a monomer having a functional group capable of bonding with a hydrophilic portion of the surfactant to prepare an adhesive resin, and the surfactant attached to the adhesive resin is difficult to move to the surface of the adhesive sheet, thereby improving water resistance. Disclosed information about the.

In addition to surfactants, water-soluble materials added to the latex deteriorate the water resistance. US Pat. No. 5,536,811 discloses a technique for removing such water-soluble materials by applying ion exchange resins.

In addition, US Patent Publication No. 2004/0143058 A1 discloses a method of manufacturing a water-based adhesive resin that is strong in whitening, and specifically, a polyhydrazide crosslinking agent is applied to enhance water resistance.

Although a number of such prior arts have been proposed, it is urgent to develop an aqueous adhesive having excellent water resistance and an adhesive sheet including the same while retaining the adhesive strength and storage stability of the oily adhesive.

In order to solve the problems of the prior art as described above, to provide an aqueous acrylic pressure-sensitive adhesive having excellent water resistance while maintaining the adhesive strength and storage stability of the oil pressure-sensitive adhesive, and a method of manufacturing the same and an adhesive sheet that prevents the transition behavior of the surfactant, including the same The purpose.

The present invention for achieving the above object,

Iii) an alkyl (meth) acrylic acid ester monomer having 2 to 14 carbon atoms in the alkyl group;

Ii) at least one monomer selected from the group consisting of allyl esters, vinyl esters, unsaturated acetates and unsaturated nitriles;

Iii) at least one monomer selected from the group consisting of unsaturated carboxylic acids and hydroxyl-containing unsaturated monomers;

Iii) a crosslinking agent comprising 5 to 15 alkylene oxide groups and having at least two groups by acrylate group, vinyl group or a mixture thereof; And

v) a surfactant having Formula 1 below; , ≪ / RTI >

The content of i) to iv) is i) 60 to 90% by weight, ii) 5 to 30% by weight, iii) 0.5 to 5% by weight and iv) 0.1 to 3% by weight, satisfying a total of 100% by weight ,

The content of the surfactant of v) provides an aqueous acrylic pressure-sensitive adhesive, characterized in that in the range of 0.3 to 15 parts by weight based on a total of 100 parts by weight of the i) to iv).

R _1- (R ₂ O)-(CH ₂ CH ₂ O) nR ₃

(Wherein R ₁ is an alkenyl group having C ₁ -C ₁₈ , R ₂ is an alkyl group having C ₁ -C ₁₀ , R ₃ is SO ₃ NH ₄ , SO ₃ Na, SO ₃ K, or H, and n is Is an integer from 1 to 20)

In addition, the present invention is a method for producing an aqueous acrylic pressure-sensitive adhesive,

Provided is a method for producing an aqueous acrylic pressure-sensitive adhesive, characterized in that the aqueous acrylic pressure-sensitive adhesive is prepared by administering a compound having the formula (1) as an surfactant and emulsion polymerization.

[Formula 1]

R _1- (R ₂ O)-(CH ₂ CH ₂ O) nR ₃

(Wherein R ₁ is an alkenyl group having C ₁ -C ₁₈ , R ₂ is an alkyl group having C ₁ -C ₁₀ , R ₃ is SO ₃ NH ₄ , SO ₃ Na, SO ₃ K, or H, and n is Is an integer from 1 to 20)

In addition, the present invention provides an adhesive sheet for forming the pressure-sensitive adhesive layer by applying the above-mentioned aqueous acrylic pressure-sensitive adhesive on a pressure-sensitive adhesive film or sheet.

Hereinafter, the present invention will be described in detail.

The aqueous acrylic pressure-sensitive adhesive of the present invention includes: i) alkyl (meth) acrylic acid ester monomers having 2 to 14 carbon atoms in the alkyl group; Ii) at least one monomer selected from the group consisting of allyl esters, vinyl esters, unsaturated acetates and unsaturated nitriles; Iii) at least one monomer selected from the group consisting of unsaturated carboxylic acids and hydroxyl-containing unsaturated monomers; Iii) a crosslinking agent comprising an alkylene oxide group and having two or more groups by acrylate group, vinyl group or a mixture thereof; And v) a surfactant.

The alkyl (meth) acrylic acid ester monomer having 2 to 14 carbon atoms in the alkyl group may be methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, or butyl ( Meth) acrylate, isobutyl acrylate, t-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl acrylate, isooctyl acrylate, octyl methacrylate, 2-ethylhexyl acrylate, isodecyl It is preferably at least one selected from the group consisting of acrylate, decyl methacrylate, dodecyl methacrylate, isobornyl methacrylate, and more preferably 3 to 7 kinds of mixtures, most preferably butylacryl. 40 to 80% by weight, 5 to 30% by weight of 2-ethylhexyl acrylate and 5 to 30% by weight of methyl methacrylate. Mixtures.

It is preferable that the alkyl (meth) acrylic acid ester monomer having 2 to 14 carbon atoms of the alkyl group of i) is included in an amount of 60 to 90% by weight. If the amount is less than 60% by weight, the initial adhesive strength of the acrylic adhesive prepared is not sufficient. If there is more than 90% by weight, there is a problem that the transfer of the pressure-sensitive adhesive to the adherend largely occurs when removed after use.

In particular, the number of carbon atoms of the alkyl group of iii) is preferably 2 to 14, but less than two, the glass transition temperature of the acrylic pressure-sensitive adhesive prepared is too high, there is a problem that the cohesive strength is lowered, if more than 14 acrylic pressure-sensitive adhesive prepared There is a problem in that the flexibility is too poor adhesive properties.

In addition, at least one monomer selected from the group consisting of ii) allyl ester, vinyl ester, unsaturated acetate and unsaturated nitrile is added to reinforce the adhesive strength of the pressure-sensitive adhesive, and is preferably vinyl acetate, vinyl butane or acrylonitrile. .

The monomer of ii) is preferably contained in 5 to 30% by weight, more preferably in 7 to 20% by weight. If less than 5% by weight of the acrylic copolymer produced is too flexible to ensure sufficient adhesive properties, if it exceeds 30% by weight excessively harden the acrylic copolymer has a problem that a significant decrease in adhesive strength occurs.

In addition, the use of vinyl acetate and acrylonitrile together as the monomer of ii) is preferable because not only the adhesion at room temperature is improved but also a synergy effect occurs in the improvement of aging adhesive properties.

In addition, at least one monomer selected from the group consisting of unsaturated carboxylic acid and hydroxyl group-containing unsaturated monomers of iii) is added to reinforce the adhesive force of the pressure-sensitive adhesive, acrylic acid, itaconic acid, maleic acid, fumaric acid, methacrylic Acid, ethyl methacrylate, hydroxymethyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate It is preferred to be selected.

The monomer of iii) is preferably contained in 0.5 to 5% by weight, if less than 0.5% by weight of the acrylic copolymer produced is too flexible to ensure sufficient adhesive properties, if the content exceeds 5% by weight acrylic air There is a problem in that the coalescence is excessively firm and a significant decrease in adhesive force occurs.

(Iii) a crosslinking agent comprising an alkylene oxide group and having two or more groups by an acrylate group, a vinyl group or a mixture thereof is introduced to reinforce cohesion (gel content control), and is an organic crosslinking agent, polyethylene glycol diacrylate , Polypropylene glycol diacrylate, 1,6-hexanediol diacrylate, trimethylol propane triacrylate, ethoxylated trimethylpropane triacrylate, tripropylene glycol diacrylate, 1,3-butanediol diacrylate, penta At least one selected from the group consisting of tritoltriacrylate, 3-trimethoxysilyl propylmethacrylate, vinyltrimethoxysilane, divinylbenzene and the like, aluminum acetylacetonate, zinc acetate, zirconium carbonate, etc. Can be.

More preferably, polyethylene glycol diacrylate, poly propylene glycol diacrylate, hexanediol ethoxylate diacrylate, hexanediol propoxyl 1,6-hexanediol propoxylate diacrylate, neopentyl glycol ethoxylate diacrylate, neopentyl glycol propoxylate diacrylate, trimethyl propane ethoxyl Trimethyl propane ethoxylate triacrylate, trimethyl propane propoxylate triacrylate, pentaerythritol ethoxylate triacrylate and pentaerythritol propoxylate triacrylate (pentaerythrito l propoxylate triacrylate) may be one or more selected from the group consisting of.

The crosslinking agent of iii) is most preferably one having a long chain length, including 5 to 15 alkylene oxide groups, and when the alkylene oxide groups are less than 5, the acrylic pressure sensitive adhesive produced is more rigid than necessary, and thus the initial adhesive strength is lowered. This is because when the acrylic pressure-sensitive adhesive to be produced is more than 15, there is a problem in that the pressure-sensitive adhesive properties are lowered.

The method of copolymerizing the monomer mixture is not particularly limited, but it may be preferable to use the emulsion polymerization to easily control the heat of reaction. The emulsion polymerization reaction is polymerized into an acrylic resin (the reaction solution containing the acrylic emulsion). In order to enable the acrylic resin to realize significant heat resistance and adhesive force, an appropriate glass transition temperature (Tg) is required, and a considerable cohesive force is realized. In order to do this, an appropriate gel content is required.

The glass transition temperature (Tg) of the acrylic resin may be -70 to 0 ℃, it is most preferred that it is -50 to -10 ℃, where the heat resistance is lowered below -50 ℃ and the adhesive attached to the surface of the adherend This is because an acrylic resin residue remains on the surface of the adherend when the coated tape is peeled off to contaminate the adherend, and when it exceeds -10 ° C, the adhesive force becomes poor.

The gel content of the acrylic resin can be adjusted by the crosslinking agent, etc., preferably 30 to 90%, more preferably 50 to 70%. If the gel content is less than 30%, the heat resistance is lowered and an acrylic resin residue remains on the surface of the adherend when peeling off the tape coated with the adhesive attached to the surface of the adherend, contaminating the adherend. Adhesion is weakened due to poor adhesion performance.

The mixture of the acrylic monomer mixture and the aqueous phase corresponding to the unsaturated monomers of the oil phase is polymerized through an emulsification process, and the one-aquatic component added to secure dispersion stability of the synthesized pressure-sensitive adhesive resin that stabilizes the monomer mixture. As the surfactant, the total dosage comprises 0.3 to 15 parts by weight relative to the total 100 parts by weight of the acrylic monomers of i) to iv), and 0.1 to 1 parts by weight of a salt containing sodium or potassium as a buffer to stabilize the pH. The emulsion is prepared by mixing the monomer mixture, water, surfactant, and the like.

The surfactant plays a role of improving initial particle generation, size control of particles and stability of particles during polymerization, and the surfactant used in the emulsion polymerization is anionic surfactant, nonionic surfactant or a mixture thereof. The anionic and nonionic surfactants may be mixed. In this case, the polymerization proceeds stably, and the storage stability of the product after polymerization is excellent.

Suitable surfactants for use in the present invention may consist of the following formula:

[Formula 1]

R _1- (R ₂ O)-(CH ₂ CH ₂ O) nR ₃

(Wherein R ₁ is an alkenyl group having C ₁ -C ₁₈ , R ₂ is an alkyl group having C ₁ -C ₁₀ , R ₃ is SO ₃ NH ₄ , SO ₃ Na, SO ₃ K, or H, and n is An integer from 1 to 20).

Specific examples thereof include polyoxyalkylene alkenyl ether ammonium sulfate, polyoxyalkylene alkenyl ether sodium sulfate, polyoxyalkylene alkenyl ether potassium sulfate, polyoxyalkylene alkenyl ether or mixtures thereof, and the like. It can be used in 0.1 to 20 parts by weight based on 100 parts by weight of the mixture, but more preferably within the range of 0.3 to 15 parts by weight, the dispersion stability of the water-based pressure-sensitive adhesive is less than 0.3 parts by weight, the adhesive strength and water resistance when it exceeds 15 parts by weight Because it falls.

In particular, since water resistance and adhesive strength are affected by the total amount of the surfactant to be added, it is preferable to use it in two stages as appropriate. For example, if 15 parts by weight is added to step 1, the input of step 2 is 0. If 0.3 parts by weight is input to step 1, 14.7 parts by weight can be added in step 2, and 5 parts by weight is entered in step 1 In 10 parts by weight or less can be added.

In this case, the polymerization reaction is not particularly limited in the case of a conventional emulsion polymerization method, but in order to facilitate the control of the reaction heat, a monomer addition method (method of adding a monomer to a preemulsion or an aging process). Or a seed polymerization method or the like.

The polymerization initiator used in the emulsion polymerization may be selected from the group consisting of persulfates of ammonium or alkali metal when the solvent is water; Hydrogen peroxide; Peroxides; It may be a water-soluble polymerization initiator such as hydroxide peroxide, but may be used together with one or more reducing agents to carry out the emulsion polymerization reaction at low temperature. These reducing agents may be sodium bisulfite, sodium metabisulfite, sodium hydrosulfite, sodium thiosulfate, sodium formaldehyde sulfoxylate, ascorbic acid and the like. These reducing agents may be sodium bisulfite, sodium metabisulfite, sodium hydrosulfite, sodium thiosulfate, sodium formaldehyde sulfoxylate, ascorbic acid and the like.

The polymerization initiator is preferably used in 0.1 to 3 parts by weight based on 100 parts by weight of the total of the monomers (iii) to (iii).

It is preferable that the temperature of the said polymerization reaction is 0-100 degreeC, and when considering the physical property of an adhesive, it is more preferable that it is 40-80 degreeC, The initiator is used individually or in mixture of 1 or more types of the said initiator and the said reducing agent. Method and the like.

The electrolyte used in the polymerization reaction is to adjust the pH and impart stability to the acrylic resin (or latex) to be polymerized, specifically, from the group consisting of sodium bicarbonate, sodium carbonate, sodium phosphate, sodium sulfate, sodium chloride, and the like. It may be one or more selected, of which sodium carbonate is preferred. The used content may be 0.1 to 2 parts by weight, more preferably 0.3 to 1 part by weight based on 100 parts by weight of the monomer mixture of i) to iv). For reference, the electrolyte may be included in the emulsion.

The acrylic emulsion may be applied to the pressure-sensitive adhesive without adjusting the acidity (pH), preferably may be applied to the pressure-sensitive adhesive after the acidity (pH) is adjusted with an alkaline material. The alkaline substance may be an inorganic substance such as hydroxide, chloride, carbonate of monovalent metal or divalent metal, ammonia or organic amine, or the like.

It is preferable that it is 6-9, and, as for the acidity (pH) of the said acrylic emulsion, it is more preferable that it is 7-8.

The aqueous acrylic pressure-sensitive adhesive may further include a thickener and a wetting agent to prevent shrinkage of the acrylic resin (or latex) generated when the pressure-sensitive adhesive is coated on the surface of the silicone release paper.

Specifically, the thickener may be CMC (carboxymethyl cellulose), acrisol, polyvinyl alcohol, starch, alginate, dextrin, and the like, of which polyvinyl alcohol is preferable. The content is preferably 0.1 to 3 parts by weight, more preferably 0.1 to 1 part by weight based on 100 parts by weight of the monomer mixture.

The wetting agent is to adhere the hydrophilic adhesive to the surface of the hydrophobic silicone release paper well, the surfactant mixture may further include glycol or alcohol. The content is preferably 0.1 to 3 parts by weight, more preferably 0.1 to 1 part by weight based on 100 parts by weight of the monomer mixture.

Since the aqueous acrylic pressure-sensitive adhesive contains a surfactant, bubbles are generated in the process of mixing the additives (thickener, wetting agent, etc.), and these bubbles can be removed by using an antifoaming agent because the coating (coating) surface of the pressure-sensitive adhesive is uneven. have.

The antifoaming agent is divided into silicone type, surfactant type, paraffin type, mineral oil type and the like. The amount is preferably 0.05 to 0.5 parts by weight based on 100 parts by weight of the monomer mixture.

The acrylic copolymer may be copolymerized by further including a tackifier at the time of manufacture to increase the adhesive force.

The tackifier may be added in an amount of 5 to 10 parts by weight based on 100 parts by weight of the total of the monomers (i) to iii), and in general, the tackifier is not particularly limited, and specific examples ( Hydrogenated Hydrocarbon Resin, Hydrogenated Rosin Resin, Hydrogenated Rosin Ester Resin, Hydrogenated Terpene Resin, Hydrogenated Terpene Phenolic Resin, Polymerized Rosin Resin and Polymerized Rosin Ester Resin Can be.

The method for producing an aqueous acrylic pressure-sensitive adhesive according to the present invention is to administer a compound having the following formula (1) as a surfactant in two stages as necessary to prevent rapid heat generation and to continuously monomer and surfactant necessary for the growth and stability of latex particles It is characterized in that an aqueous acrylic pressure-sensitive adhesive is prepared by emulsion polymerization while being injected into.

[Formula 1]

R _1- (R ₂ O)-(CH ₂ CH ₂ O) nR ₃

(Wherein and R ₁ is an alkenyl group of C ₁ -C _18, R ₂ is a C ₁ -C ₁₀ alkyl group, R ₃ is R ₃ is _{SO 3 NH 4, SO 3 Na} , SO 3 K, or H, N is an integer of 1 to 20)

In the process of preparing the aqueous acrylic pressure-sensitive adhesive including the above-mentioned administration process, the emulsion polymerization process is a water and electrolyte to the surfactant of Formula 1 in the range of 0.3 to 15 parts by weight, the temperature is raised to 70 ℃ to remove oxygen and dissolve the initiator A first step (step a) of preparing a solution, a second step (b) of preparing an emulsion by administering water, an electrolyte and a surfactant of Formula 1 to the monomer mixture, a second in the solution of the first step The emulsion and the initiator of the step is continuously added, and after the temperature is raised to 80 ℃ to prepare an acrylic emulsion (step c), the step of adjusting the pH of the acrylic emulsion to 6-9 (step d).

At this time, the surfactant is polyoxyalkylene alkenyl ether ammonium sulfate, polyoxyalkylene alkenyl ether sodium sulfate, polyoxyalkylene alkenyl ether potassium sulfate, polyoxyalkylene alkenyl ether or a mixture thereof in the preparation of the first step of the solution Is administered in the range of 0.3 to 15 parts by weight with respect to 100 parts by weight of the monomer mixture, and when the emulsion is prepared in the second step, the sum of the first stage dose is within 15 parts by weight or less based on 100 parts by weight of the monomer mixture. It is preferable to make 0.3-15 weight part in consideration of initial reaction stability.

In this case, the step a allows the initial latex particles prepared by pre-injecting materials other than the monomers to be able to absorb the exothermic generated during the reaction well so that the latex particles can be stably dispersed. At this time, since oxygen has a strong reactivity with radicals, it may cause a delay of an initial reaction that is not rich in an initiator, so that oxygen is removed by adding nitrogen to prevent this.

Also in step b, the monomer mixture comprises i) 60 to 90% by weight of an alkyl (meth) acrylic acid ester monomer having 2 to 14 carbon atoms as described above, i) an allyl ester, vinyl ester, unsaturated acetate and unsaturated nitrile. 5 to 30% by weight of one or more monomers selected from the group; Iii) from 0.5 to 5% by weight of at least one monomer selected from the group consisting of acrylic acid and methacrylic acid, and iii) from 0.1 to 2 crosslinking agents comprising alkylene oxide groups and having at least two groups by acrylate groups, vinyl groups or mixtures thereof. It is preferred to satisfy 3% by weight, in total of 100% by weight of the formulation of.

Furthermore, the continuous input of preparing the emulsion in step c prevents rapid heat generation by dividing the monomers and continuously adds the surfactant required for stability since latex particles are grown.

In addition, the water used as the aqueous reaction solvent is preferably used in the range of 10 to 300 parts by weight based on the monomer mixture in consideration of the stability and productivity aspects of the latex, more specifically in the step a range of 5 to 200 parts by weight. Used in, the b step is to be used in the range of 15 to 250 parts by weight.

The aqueous acrylic pressure-sensitive adhesive prepared in this way is applied on the pressure-sensitive adhesive film or sheet to form a pressure-sensitive adhesive layer, and excellent workability while preventing the surfactant from transitioning to the surface of the pressure-sensitive adhesive sheet.

The pressure-sensitive adhesive sheet is characterized in that the interior and exterior materials, interior materials, advertising film, or a pressure-sensitive adhesive film or sheet of the label, wherein the pressure-sensitive adhesive layer has a thickness of 10 to 100 ㎛, preferably 20 to 30 ㎛ The physical properties are secured and the drying time is not long, so the economic effect is excellent.

The pressure-sensitive adhesive layer can be formed on one or both sides of the film or sheet, and the specific method is not particularly limited. For example, the acrylic pressure-sensitive adhesive is applied to the surface of the film or sheet using a bar coder, and then dried. Alternatively, the acrylic pressure-sensitive adhesive may be applied to the surface of the releaseable substrate (release paper) and dried, and then, the pressure-sensitive adhesive layer formed on the surface of the releaseable substrate may be transferred to a film or sheet to prepare a pressure-sensitive adhesive product specimen.

According to the present invention, the interior and exterior materials, interior materials, advertising films, labels and other adhesives, which have enhanced water resistance by suppressing the phenomenon of the conventional surfactant moving to the surface of the adhesive sheet and minimizing the amount of moisture absorbed when contacted with water. There is an effect of providing an acrylic pressure-sensitive adhesive that can be applied to a required film and the like and a method of manufacturing the same.

Hereinafter, preferred examples are provided to aid the understanding of the present invention, but the following examples are merely illustrative of the present invention and various changes and modifications within the scope and spirit of the present invention will be apparent to those skilled in the art. It is natural that modifications and variations fall within the scope of the appended claims.

< Example  1>

<Acrylic system Emulsion  Manufacturing>

A thermometer, a stirrer, a dropping funnel, 20% by weight of the R ₃ of the formula (I) for the SO ₃ NH ₄ in a 3-liter glass reactor equipped with a nitrogen inlet tube and a reflux condenser, a water 300g, sodium carbonate 1g, surfactants ( 20% concentration by weight) 15 g of polyoxyalkylene alkenyl ether ammonium sulfate and 15 g of 20% by weight aqueous solution of polyoxyalkylene alkenyl ether in which R ₃ in Formula 1 were respectively injected as another surfactant.

While stirring the glass reactor, the inside of the reactor was replaced with nitrogen, and then heated to 70 ° C. under a nitrogen atmosphere, and maintained for 30 minutes. 1 g of ammonium persulfate was added to the glass reactor and stirred for 10 minutes to dissolve it.

Separately, 20% by weight of polyoxyalkylenal to 1000 g of a monomer mixture of 400 g of butyl acrylate, 430 g of 2-ethylhexyl acrylate, 100 g of methyl methacrylate, 50 g of acrylonitrile, 15 g of acrylic acid, and 5 g of polypropylene diacrylate A solution consisting of 50 g of ammonium sulfate ammonium sulfate, 50 g of 20 wt% polyoxyalkylene alkenyl ether aqueous solution, 2 g of sodium carbonate, and 500 g of water was added and mixed to prepare an emulsion. The prepared emulsion was continuously added to the reactor for 4 hours, and 100 g of 5% by weight aqueous ammonium persulfate solution was continuously added thereto.

Thereafter, 10 g of the emulsion and 5 wt% ammonium persulfate aqueous solution were further added to the glass reactor, and then heated to 80 ° C. for 30 minutes, maintained for 1 hour, and cooled to room temperature to prepare an acrylic emulsion. The pH was adjusted to 7.5 by adding 28% by weight aqueous ammonia solution to the acrylic emulsion.

The acrylic emulsion was dried in a vacuum oven at 50 ° C. for 24 hours to obtain an adhesive resin, and the glass transition temperature analyzed by a calorimeter was −40.0 ° C.

<Preparation of Aqueous Acrylic Adhesive and Adhesive Tape Specimen>

To 100 g of the acrylic emulsion (pH 7.5) prepared as described above, 1 g of a silicone-based antifoaming agent and 20 g of a wetting agent were added as a thickener and stirred for 2 hours to apply an aqueous acrylic pressure-sensitive adhesive to a silicone release paper sheet and dried in an oven at 120 ° C. for 3 minutes to 20 μm. A pressure-sensitive adhesive sheet was prepared.

The adhesive sheet was laminated with a PVC sheet to obtain an adhesive tape, and the adhesive sheet was cut to a size of 1 inch × 100 mm to prepare an adhesive tape specimen.

< Example  2>

The same process as in Example 1 was repeated except that polyoxyalkylene alkenylether ammonium sulfate was replaced with polyoxyalkylene alkenylether sodium sulfate. The obtained acrylic emulsion was dried in a vacuum oven at 50 ° C. for 24 hours to obtain an adhesive resin, and the glass transition temperature analyzed by a calorimeter was -40.0 ° C.

< Example  3>

The same process as in Example 1 was repeated except that polyoxyalkylene alkenylether ammonium sulfate was replaced with polyoxyalkylene alkenylether potassium sulfate. The obtained acrylic emulsion was dried in a vacuum oven at 50 ° C. for 24 hours to obtain an adhesive resin, and the glass transition temperature analyzed by a calorimeter was -40.0 ° C.

< Comparative example  1>

Example 1 except that the polyoxyalkylene alkenyl ether ammonium sulfate was replaced with sodium polyoxyethylene lauryl ether sulfate, and the polyoxyalkylene alkenyl ether aqueous solution was replaced with polyoxyethylene lauryl ether. The same method was repeated.

The acrylic emulsion was dried in a vacuum oven at 50 ° C. for 24 hours to obtain an adhesive resin, and the glass transition temperature thereof was analyzed by a calorimeter.

< Comparative example  2>

The same method as in Comparative Example 1 was repeated except that sodium polyoxyethylene lauryl ether sulfate was replaced with sodium polyoxyethylene alkylaryl sulfate in Comparative Example 1.

The acrylic emulsion was dried in a vacuum oven at 50 ° C. for 24 hours to obtain an adhesive resin, and the glass transition temperature of which was analyzed by a calorimeter was −40.3 ° C.

< Comparative Example 3>

The same method as in Comparative Example 1 was repeated except that sodium polyoxyethylene lauryl ether sulfate was replaced with ammonium polyoxyethylene alkylaryl sulfate in Comparative Example 1.

The acrylic emulsion was dried in a vacuum oven at 50 ° C. for 24 hours to obtain an adhesive resin, and the glass transition temperature of the acrylic emulsion was analyzed by a calorimeter.

< Comparative Example 4>

The same method as in Comparative Example 1 was repeated except that polyoxyethylene lauryl ether was replaced with polyoxyethylene lauryl ester in Comparative Example 1.

The acrylic emulsion was dried in a vacuum oven at 50 ° C. for 24 hours to obtain an adhesive resin, and the glass transition temperature of which was analyzed by a calorimeter was −40.6 ° C.

< Comparative Example 5>

The same procedure as in Comparative Example 1 was repeated except that polyoxyethylene lauryl ether was replaced with polyoxyethylene oleyl ester in Comparative Example 1.

The acrylic emulsion was dried in a vacuum oven at 50 ° C. for 24 hours to obtain an adhesive resin, and the glass transition temperature thereof was analyzed by a calorimeter.

< Comparative Example 6>

The same method as in Comparative Example 1 was repeated except that polyoxyethylene lauryl ether was replaced with polyoxyethylene lauryl amine in Comparative Example 1.

The acrylic emulsion was dried in a vacuum oven at 50 ° C. for 24 hours to obtain an adhesive resin, and the glass transition temperature analyzed by a calorimeter was −40.3 ° C.

[ Test Example ]

The properties of the adhesive tapes prepared in Examples 1 to 3 and Comparative Examples 1 to 6 were measured by the following method, and the results are summarized in Table 1 below.

* Adhesion test: The adhesive force of the adhesive tape specimen was reciprocated five times at a speed of 300 mm / min with a 2 kg roll in accordance with JIS Z 0237, attached to the SUS plate, aged at room temperature for 3 days, and then 5 mm / sec using a TA texture analyzer. It measured while peeling 180 degrees at a speed | rate.

* Acquisition adhesiveness measurement: The adhesive sheet attached to the SUS plate was obtained by taking water for 3 days, taken out, and then the water was removed and measured while peeling 180 ° at a rate of 5 mm / sec using a TA texture analyzer.

division Surfactants adhesiveness
(g / in) Gluing Adhesion
(g / in) Adhesiveness reduction rate
(%) Example 1 Polyoxyalkylene alkenyl ether ammonium sulfate +
Polyoxyalkylene alkenyl ether 1232 920 25 Example 2 Sodium polyoxyalkylene alkenyl ether
Polyoxyalkylene alkenyl ether 1209 850 29 Example 3 Potassium polyoxyalkylene alkenyl ether sulfate
Polyoxyalkylene alkenyl ether 1223 870 30 Comparative Example 1 Sodium Polyoxyethylene Lauryl Ether Sulfate + Polyoxyethylene Lauryl Ether 1215 756 37 Comparative Example 2 Sodium polyoxyethylenealkylarylsulfate +
Polyoxyethylene lauryl ether 1206 723 40 Comparative Example 3 Ammonium Polyoxyethylene Alkyl Sulfate +
Polyoxyethylene lauryl ether 1253 864 31 Comparative Example 4 Sodium Polyoxyethylene Lauryl Ether Sulfate + Polyoxyethylene Lauryl Ester 1196 747 38 Comparative Example 5 Sodium Polyoxyethylene Lauryl Ether Sulfate +
Polyoxyethylene oleyl ester 1224 772 37 Comparative Example 6 Sodium Polyoxyethylene Lauryl Ether Sulfate +
Polyoxyethylene laurylamine 1235 782 37

As shown in Table 1, Comparative Examples 1 to 6 compared to Examples 1 to 3 all showed a tendency to decrease the adhesion. In addition, in the case of Example 1, the decrease in adhesion is 25%, in the case of Example 2, the decrease in adhesion is 29%, in the case of Example 3, the decrease in adhesion is 30%, which is smaller than the comparative examples 1 to 6. I could confirm it.

Claims (14)

Iii) an alkyl (meth) acrylic acid ester monomer having 2 to 14 carbon atoms in the alkyl group; Ii) at least one monomer selected from the group consisting of allyl esters, vinyl esters, unsaturated acetates and unsaturated nitriles; Iii) at least one monomer selected from the group consisting of unsaturated carboxylic acids and hydroxyl-containing unsaturated monomers; And iii) a crosslinking agent comprising 5 to 15 alkylene oxide groups and having at least two groups in acrylate groups, vinyl groups or mixtures thereof; In the aqueous acrylic pressure-sensitive adhesive comprising a, v) A surfactant, which is a polyoxyalkylene alkenyl ether ammonium sulfate, polyoxyalkylene alkenyl ether sodium sulfate, and a polyoxyalkylene alkenyl ether potassium sulfate independently selected from a first surfactant, and a polyoxyalkylene alkenyl ether Aqueous acrylic emulsion pressure-sensitive adhesive having excellent adhesive force, storage stability and water resistance, comprising 2 to 0.3 parts by weight with respect to 100 parts by weight of the total content of i) to iv). delete The method of claim 1, The monomer of (i) is methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl acrylate, t- Butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl acrylate, isooctyl acrylate, octyl methacrylate, 2-ethylhexyl acrylate, isodecyl acrylate, decyl methacrylate, dodecyl methacrylate An aqueous acrylic emulsion pressure-sensitive adhesive having excellent adhesive strength, storage stability and water resistance, characterized in that at least one selected from the group consisting of a rate and isobornyl methacrylate. The method of claim 1, The monomer of i) is 40 to 80% by weight of butyl acrylate, 5 to 30% by weight of 2-ethylhexyl acrylate and 5 to 30% by weight of methyl methacrylate, adhesive strength, storage stability and water resistance Excellent aqueous acrylic emulsion pressure sensitive adhesive. The method of claim 1, The monomer of ii) comprises vinyl acetate, vinyl butane, acrylonitrile or a mixture thereof in an amount of 5 to 30% by weight. The aqueous acrylic emulsion pressure sensitive adhesive having excellent adhesion, storage stability and water resistance. The method of claim 1, The monomer of i) may be acrylic acid, itaconic acid, maleic acid, fumaric acid, methacrylic acid, ethyl methacrylic acid, hydroxymethyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, An aqueous acrylic emulsion pressure sensitive adhesive having excellent adhesion, storage stability and water resistance, comprising 0.5 to 5% by weight of at least one selected from the group consisting of 2-hydroxyethyl methacrylate and 2-hydroxypropyl methacrylate. The method of claim 1, The crosslinking agent of (i) is polyethylene glycol diacrylate, polypropylene glycol diacrylate, hexanediol ethoxylate diacrylate, hexanediol propoxylate diacrylate, neopentyl glycol ethoxylate diacrylate and neopentyl. Selected from the group consisting of glycol propoxylate diacrylate, trimethyl propane ethoxylate triacrylate, trimethyl propane propoxylate triacrylate, pentaerythritol ethoxylate triacrylate and pentaerythritol propoxylate triacrylate An aqueous acrylic emulsion pressure-sensitive adhesive excellent in adhesion, storage stability and water resistance, characterized in that it comprises at least one in 0.1 to 3% by weight. delete To the solution of water, electrolyte and surfactant, the monomer mixture of i) to iv) of claim 1, an emulsion of water, electrolyte and surfactant, and an initiator are added to prepare an acrylic emulsion by emulsion polymerization, The surfactants added to the solution and the emulsion are respectively administered in a range of 0.3 to 15 parts by weight based on 100 parts by weight of the monomer mixture of claim 1) v) surfactant mixture, i) to iv). Method for producing an aqueous acrylic emulsion pressure-sensitive adhesive, characterized in that the pH is adjusted to 6 to 9 after the emulsion polymerization. delete delete delete The pressure-sensitive adhesive sheet which forms the pressure-sensitive adhesive layer by applying the aqueous acrylic emulsion pressure-sensitive adhesive according to any one of claims 1 to 3 on a pressure-sensitive adhesive film or sheet. The method of claim 13, The adhesive film or sheet is a pressure-sensitive adhesive sheet, characterized in that the building interior and exterior materials, interior materials, advertising films, or adhesive film or sheet of the label.