KR20120076817A - Pressure sensitive adhesive for protective film having anti-static property - Google Patents

Abstract

PURPOSE: An aqueous emulsion acrylic adhesive for protective film is provided to minimize static electricity capable of being generated at peeling a protective film by using a hydrophilic monomer with antistatic property, and to have excellent film adhesion, storage stability, staining resistance, and low peeling force which are required for adhesive for protective film. CONSTITUTION: An aqueous emulsion acrylic adhesive for protective film is formed by polymerization of an acrylic monomer comprising alkoxypolyalkylene glycol mono(meth)acrylic acid ester in chemical formula 1. In chemical formula 1, R^1 is a hydrogen atom or methyl group, and R^2O is C2-4 oxyalkylene of one or more kinds. When having two or more kinds, the C2-4 oxyalkylene can be block shape or random shape. R^3 is C1-4 alkyl group, and m is an integer from 5-50, as number of average addition moles.

Description

Pressure sensitive adhesive for protective film having anti-static property

The present invention relates to an aqueous emulsion acrylic pressure-sensitive adhesive for a protective film and a method of manufacturing the same, and more particularly, to an aqueous emulsion acrylic resin made of an acrylic monomer containing an alkylene glycol, which may exhibit antistatic properties, for protecting an optical member. The present invention relates to an aqueous emulsion acrylic pressure-sensitive adhesive for a protective film, which provides antistatic property applied to a film and does not leave contaminants without damaging the surface of the substrate during peeling, and which has excellent workability.

The protective film is mainly used to prevent damage to the surface of the product due to physical impact that may occur in the process of transport, storage, assembly, and the like. When this role is finished, the protective film is removed from the substrate. If the peeling force of the protective film is stronger than necessary, the surface of the substrate may be damaged or contaminated, and in particular, the workability may be deteriorated due to the effect of increasing the adhesive force at high speed. Therefore, although a protective film having a low peel force is made, these products have a weak adhesive force between the film and the adhesive resin, causing a problem that the adhesive resin is transferred to the surface of the product after peeling to contaminate the substrate.

 In addition, the protective film and the like has high electrical insulation and generates static electricity during peeling. Therefore, when the protective film is peeled off from the optical member such as the polarizing plate or the prism sheet, static electricity may be generated, and the remaining static electricity may cause defects in the liquid crystal display. Static electricity can also cause dirt or dirt to adsorb onto the film, causing surface contamination. In order to solve the problem caused by static electricity as described above, the surface protection film for an optical member is subjected to various antistatic treatment.

Korean Patent Laid-Open Publication No. 2009-0109472 includes a metal salt antistatic agent in an oily pressure-sensitive adhesive composition to sufficiently improve the generation of static electricity without impairing the physical properties of the adhesive itself, such as adhesiveness and durability, thereby providing improved antistatic properties. However, when the protective film is peeled off from the optical member, there is a problem that the metal salt antistatic agent passes over to the optical member to contaminate the surface.

An object of the present invention is to solve the problems of the prior art, and relates to an aqueous adhesive used for a protective film to protect the surface of the optical member and does not damage the surface of the product at the time of peeling without leaving contaminants static electricity during peeling It is to provide an aqueous emulsion pressure-sensitive adhesive and a method for producing the same that does not occur.

Another object of the present invention is to provide an emulsion pressure-sensitive adhesive and a method for producing the same, which implements low adhesion and prevents pressure-sensitive adhesive transition from a film.

The above and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object, the present invention is an aqueous emulsion acrylic pressure-sensitive adhesive containing an aqueous emulsion acrylic resin made of an acrylic monomer containing an alkylene glycol that can exhibit antistatic properties and an alkylene glycol that can exhibit antistatic properties To provide.

The present invention also provides a method for producing an aqueous emulsion acrylic resin prepared from an acrylic monomer containing an alkylene glycol capable of exhibiting the antistatic property.

In another aspect, the present invention provides a protective film for an optical member formed by coating the prepared aqueous emulsion acrylic pressure-sensitive adhesive on one side or both sides of the film.

The aqueous emulsion acrylic pressure-sensitive adhesive according to the present invention can minimize the static electricity generated when the protective film is peeled off by using a hydrophilic monomer that can exhibit antistatic properties. And the film adhesion, storage stability, stain resistance and low peeling force required for the pressure-sensitive adhesive for the protective film has an excellent effect.

Hereinafter, the present invention will be described in detail.

An aqueous emulsion acrylic pressure-sensitive adhesive comprising an aqueous emulsion acrylic resin formed by polymerizing an acrylic monomer including an alkylene glycol that may exhibit antistatic properties and an alkylene glycol that may exhibit antistatic properties.

In addition, the present invention is i) 80 to 99.8% by weight of at least one selected from the group consisting of alkyl acrylates, alkyl methacrylates, alkylene glycols including alkylene glycols, allyl esters, vinyl esters, unsaturated acetates and unsaturated nitriles; ii) 0.1 to 10% by weight of unsaturated carboxylic acid, hydroxyl-containing unsaturated monomer or mixtures thereof; And iii) 0.1 to 10% by weight of the internal crosslinking agent; provides an emulsion acrylic resin formed by polymerizing a monomer mixture comprising a.

Alkylene glycol  Containing monomer

When the alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer represented by the following formula (1) is used, an adhesive showing antistatic property can be prepared. As the alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer, it is preferable to use 5 to 50 parts by weight of the total weight constituting the emulsion acrylic resin, more preferably 5 to 20 parts by weight.

In Chemical Formula 1,

R ¹ is a hydrogen atom or a methyl group,

R ² O may be one or two or more oxyalkylenes having 2 to 4 carbon atoms, and in the case of two or more, may be added in a block or random phase,

R ³ is an alkyl group having 1 to 4 carbon atoms,

m is an integer of 5-50 in the average added mole number of an oxyalkyl group.

emulsion  Acrylic resin

The emulsion acrylic resin according to the present invention is i) at least one selected from the group consisting of alkyl acrylates, alkyl methacrylates, alkyl monomers including alkylene glycols, allyl esters, vinyl esters, unsaturated acetates and unsaturated nitriles 80 to 99.8 weight%; ii) 0.1 to 10% by weight of unsaturated carboxylic acid, hydroxyl-containing unsaturated monomer or mixtures thereof; And iii) 0.1 to 10% by weight of an internal crosslinking agent.

Preferred emulsion acrylic adhesive resins are i) alkylacrylates, alkylmethacrylates, alkoxypolyalkylene glycol mono (meth) acrylic acid esters, allyl esters, vinyl esters, unsaturated acetates, unsaturated nitriles or mixtures thereof 80 to 99.8% by weight, ii) 0.1 to 10% by weight of unsaturated carboxylic acid, hydroxyl group-containing unsaturated monomer or mixtures thereof, and iii) 100 parts by weight of a monomer mixture consisting of 0.1 to 10% by weight of internal crosslinking agent are prepared by emulsion polymerization.

The alkyl acrylate monomer is an acrylate compound substituted with an alkyl group having 1 or more carbon atoms, specifically, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, heptyl acrylate. , Isooctyl acrylate, 2-ethylhexyl acrylate and isodecyl acrylate is preferably one or more selected from the group consisting of, but is not limited thereto.

The alkyl methacrylate monomer is a methacrylate compound in which an alkyl group having 1 or more carbon atoms is substituted, specifically, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, t -Butyl methacrylate, pentyl methacrylate, hexyl methacrylate, 2-ethylhexyl acrylate, octyl methacrylate, decyl methacrylate, dodecyl methacrylate and isobornyl methacrylate It is preferably one or more, but is not limited thereto.

The allyl ester, vinyl ester, unsaturated acetate, unsaturated nitrile or a mixture thereof is added to reinforce the adhesive strength of the pressure-sensitive adhesive, and more specifically, vinyl acetate, vinyl butylate, and the like.

Alkyl acrylate, alkyl methacrylate, allyl ester, vinyl ester, unsaturated acetate, unsaturated nitrile or a mixture thereof may be used in the monomers of 80 to 99.8 wt%, preferably butyl acrylate or 2-ethylhexyl acryl. It is good to use rate alone or more preferably, mixing.

The unsaturated carboxylic acid, hydroxyl group-containing unsaturated monomer or a mixture thereof is added to reinforce the adhesive strength of the tackifier, and reacts with an external crosslinking agent to improve the cohesive force of the adhesive resin and to enhance the adhesion force between the film and the surface of the substrate when peeling off the protective film. It serves to prevent the transfer of adhesive resin into.

Specific examples of the unsaturated carbonic acid include acrylic acid, itaconic acid, maleic acid, fumaric acid, methacrylic acid or ethyl methacrylic acid, and specific examples of the hydroxyl group-containing unsaturated monomer include hydroxy methyl acrylate and 2-hydroxy. Ethyl acrylate, 2-hydroxy propyl acrylate, 2-hydroxyethyl methacrylate or 2-hydroxypropyl methacrylate. It is preferable to use acrylic acid or methacrylic acid which are unsaturated carbonic acid among these.

When the unsaturated carboxylic acid, hydroxyl group-containing unsaturated monomer or a mixture thereof is less than 0.1% by weight, the crosslinking degree with the external crosslinking agent may be insufficient, which may contaminate the surface of the substrate when the protective film is peeled off. It is so strong that the adhesion can deteriorate.

The crosslinking agent is to prevent the transfer of the adhesive resin to the surface of the substrate during peeling by reinforcing the cohesive force of the adhesive resin and improving the adhesion with the film, and is also required to maintain a suitable low peeling force as a protective film.

The internal crosslinking agent is an organic crosslinking agent including two or more unsaturated groups, and is characterized in that radical polymerization is possible during emulsion polymerization. Examples of the internal crosslinking agent include allyl methacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, hexanediol ethoxylate diacrylate, ethylene glycol dimethacrylate, Hexanediol ethoxylate diacrylate, hexanediol propoxylate diacrylate, neopentyl glycol ethoxylate diacrylate, neopentyl glycol propoxylate diacrylate, trimethyl propane ethoxylate triacrylate, trimethyl propane prop It may be one or more selected from foxylate triacrylate, pentaerythritol ethoxylate triacrylate, pentaerythritol propoxylate triacrylate, vinyltrimethoxysilane and divinylbenzene, but is not limited thereto. Preferably allyl methacrylate is used.

In addition, when the internal crosslinking agent is less than 0.1% by weight, the internal crosslinking strength or cohesive strength is insufficient, and thus it is difficult to obtain sufficient durability. Since adhesion is not implemented, flexibility and durability deteriorate and peeling easily occurs, so that it may be difficult to bond with an optical film.

The emulsion acrylic resin may be prepared by a) dispersing and stabilizing the monomer mixture in an aqueous phase, and then adding one or more water-soluble substances selected from the group consisting of surfactants, buffers, initiators, reducing agents, electrolytes, thickeners, wetting agents, and antifoaming agents to form an emulsion. It is preferable to prepare and b) polymerize the said emulsion liquid and to obtain an acrylic emulsion.

The water-soluble substance is used 1 to 20 parts by weight based on 100 parts by weight of the monomer mixture. When the amount of the water-soluble substance is less than 1 part by weight, the monomer conversion rate of the emulsion polymerization is lowered and the stability is sharply lowered, so that it is not a polymer. The phenomenon of deterioration occurs.

The emulsion acrylic pressure-sensitive adhesive according to the present invention stabilizes the acrylic monomer mixture dispersed in the water phase during the synthesis process, the composition of the water-soluble material added to ensure the dispersion stability of the synthesized adhesive resin is 0.1 to 10 surfactant to 100 parts by weight of monomer It is preferable to comprise 0.1-5 weight part of salts containing a weight part and sodium or potassium as a buffer. The detailed description of the details of the preparation of the emulsion of a) and the acrylic emulsion of b) is the same as that described for the aqueous emulsion acrylic pressure-sensitive adhesive.

The polymerization reaction is not particularly limited in the case of a conventional emulsion polymerization method, and in order to facilitate the control of the reaction heat, a monomer addition method (method of adding a monomer in a preemulsion process or an aging process) or seed. (seed) polymerization method and the like can be used.

The monomer mixture of i) to iii) is polymerized into an acrylic resin (the reaction solution including the acrylic emulsion) by an emulsion polymerization reaction. In order to enable the acrylic resin to realize a significant heat resistance and adhesive force, an appropriate glass transition temperature ( Tg) is required, and an appropriate gel content is required to achieve significant cohesion.

The emulsion acrylic resin may be applied to the pressure-sensitive adhesive without adjusting the pH (pH), preferably the acidity (pH) is adjusted to an alkaline material, and then may be applied to the pressure-sensitive adhesive.

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.

As for acidity (pH) of the said emulsion acrylic resin, 4-9 are preferable and 7-8.

The glass transition temperature (Tg) of the emulsion acrylic resin may be -60 to 0 ℃, preferably -50 to -10 ℃, more preferably -40 to 20 ℃, less than -60 ℃, heat resistance This lowers, and the acrylic resin residue remains on the adherend surface when peeling off the tape coated with the adhesive adhered to the adherend surface, and contaminates the adherend.

The gel content of the emulsion acrylic resin may be controlled by the crosslinking agent or the like, preferably 50% by weight or more, more preferably 80% by weight or more. When the gel content is less than 50% by weight, the peeling force is so strong that the workability is bad when the protective film is peeled off at high speed, and the surface of the product may be damaged.

Water-soluble substance

The composition of the water-soluble substance added to stabilize the acrylic monomer mixture dispersed in the water phase and to ensure the dispersion stability of the synthesized adhesive resin is 0.1 to 10 parts by weight of surfactant to 100 parts by weight of monomer, sodium or as a buffer to stabilize the pH It comprises a 0.1 to 5 parts by weight of a salt containing potassium.

The emulsion is prepared by mixing the monomer mixture, water, surfactant, and the like.

The surfactant is used for the initial particle generation during the polymerization reaction, the size control of the produced particles and the stability of the particles, and is composed of a hydrophilic group and a lipophilic group, and is divided into anionic, cationic and nonionic surfactants. In general, anionic and nonionic surfactants are used a lot, and they may be mixed with each other to compensate for mechanical stability and chemical stability.

The surfactant is preferably used in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the monomer mixture, and more preferably used in an amount of 1 to 5 parts by weight, when less than 0.1 parts by weight, the dispersion stability of the aqueous adhesive resin is lowered, When it exceeds 10 weight part, adhesive force and water resistance become low.

The polymerization initiator is preferably a water-soluble pyrolysis initiator, and specific examples thereof include persulfates of ammonium or alkali metals, hydrogen peroxide, peroxides, hydroperoxides, and the like. It can be used together with the above.

The reducing agent may be sodium bisulfite, sodium metabisulfite, sodium hydrosulfite, sodium thiosulfate, sodium formaldehyde sulfoxylate, ascorbic acid, and the like.

It is preferable that the temperature of the said polymerization reaction is 0-100 degreeC, and it is more preferable that it is 40-80 degreeC in consideration of the physical property of an adhesive, The method of using the said initiator individually or in mixture of the said initiator and the said reducing agent 1 or more types. And so on.

The electrolyte used in the polymerization reaction is to adjust the pH and to impart stability to the polymerized acrylic resin (or latex), specifically selected from the group consisting of sodium bicarbonate, sodium carbonate, sodium phosphate, sodium sulfate, sodium chloride, and the like It may be one or more, preferably sodium carbonate, based on 100 parts by weight of the monomer mixture may be from 0 to 5 parts by weight, preferably 0.1 to 1 parts by weight. For reference, the electrolyte may be included in the emulsion.

The aqueous emulsion acrylic pressure-sensitive adhesive is foamed in the process of mixing the post-treatment material (thickening agent, wetting agent, etc.) including a surfactant, these bubbles make the coating (coating) surface of the pressure-sensitive adhesive, using an antifoaming agent Can be removed

The antifoaming agent is divided into silicone-based surfactants, paraffin-based, mineral oil-type, etc., preferably silicone-based, the amount is preferably 0.05 to 1 parts by weight based on 100 parts by weight of the monomer mixture.

An aqueous emulsion acrylic pressure sensitive adhesive having excellent adhesive strength and storage stability of the present invention is characterized by comprising the above-mentioned aqueous emulsion acrylic resin and an external crosslinking agent.

The external crosslinking agent is characterized by increasing the adhesive strength and chemical resistance of the pressure-sensitive adhesive, it is preferably 0.5 to 5 parts by weight of the external crosslinking agent relative to 100 parts by weight of the emulsion acrylic resin. When the external crosslinking agent is used in less than 0.5 parts by weight, the increase in the adhesive strength to be obtained using the external crosslinking agent is insignificant, and even when used in excess of 5 parts by weight, the adhesive strength no longer increases. The external crosslinking agent is selected from at least one selected from the group consisting of trimethylolpropine tris- (1- (2-methyl) aziridino) propionate, polyaziridine aluminum, aluminum acetylacetonate, zinc acetate and zirconium carbonate It is.

In the production method of the pressure-sensitive adhesive, the present invention is a composition of the adhesive resin in the aqueous emulsion acrylic pressure-sensitive adhesive, i) alkyl acrylate, alkyl methacrylate, allyl ester, vinyl ester, unsaturated acetate, unsaturated nitrile or mixtures thereof 80 to 99.8% by weight, ii) 0.1 to 10% by weight of unsaturated carboxylic acid, hydroxyl-containing unsaturated monomer or mixtures thereof, iii) 100 parts by weight of a monomer mixture consisting of 0.1 to 10% by weight of internal crosslinking agent; And b) polymerizing the emulsion to prepare an acrylic emulsion.

Protective film

In addition, the present invention provides a protective film formed by coating the aqueous emulsion acrylic pressure-sensitive adhesive on one side or both sides of the film.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Changes and modifications may fall within the scope of the appended claims.

[Example]

Example  One

The emulsion acrylic resin was synthesized as follows.

200 g of water, 1 g of sodium carbonate, 15 g of 20% by weight sodium polyoxyethylene lauryl ether sulfate as an anionic surfactant, nonionic interface in a 3 L capacity organic reactor equipped with thermometer, stirrer, dropping funnel, nitrogen inlet tube and reflux cooler 15 g of polyoxyethylene lauryl ether aqueous solution as an activator was injected. 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.

Separately, 20 g of a monomer mixture of 500 g of butyl acrylate, 430 g of 2-ethylhexyl acrylate, 50 g of alkoxypolyethylene glycol mono (meth) acrylic acid ester monomer (EO = 5), 20 g of acrylic acid, and 10 g of allylmethacrylate were mixed. An emulsion was prepared by adding and mixing 35 g of sodium polyoxyethylene lauryl ether sulfate by weight, 35 g of 20 wt% polyoxyethylene lauryl ether aqueous solution, 2 g of sodium carbonate, and 560 g of water.

1 g of ammonium persulfate was added to the glass reactor and 1 g of ammonium persulfate was added to the glass reactor for 10 minutes and stirred for 10 minutes to dissolve.

120 g of the emulsion and 120 g of 3 wt% ammonium persulfate aqueous solution were added to the glass reactor for 4 hours, and then 20 g of 3 wt% ammonium persulfate aqueous solution was further added, followed by heating to 80 ° C. for 30 minutes and at this temperature for 1 hour. After maintaining, and cooled to room temperature to prepare an emulsion acrylic resin.

The pH was adjusted to 7.5 by adding an aqueous 28% by weight aqueous ammonia solution to the emulsion acrylic resin.

Example  2

The same procedure as in Example 1 was carried out except that the monomer composition of Example 1 was changed to 380 g of 2-ethylhexyl acrylate and 100 g of an alkoxy polyethylene glycol mono (meth) acrylic acid ester monomer (EO = 5).

Example  3

The same procedure as in Example 1 was carried out except that the monomer composition of Example 1 was changed to 330 g of 2-ethylhexyl acrylate and 150 g of an alkoxy polyethylene glycol mono (meth) acrylic acid ester monomer (EO = 5).

Example  4

The same procedure as in Example 1 was carried out except that the monomer composition of Example 1 was changed to 280 g of 2-ethylhexyl acrylate and 200 g of an alkoxy polyethylene glycol mono (meth) acrylic acid ester monomer (EO = 5).

Example  5

The same procedure as in Example 1 was carried out except that the monomer composition of Example 1 was changed to 430 g of 2-ethylhexyl acrylate and 50 g of an alkoxy polyethylene glycol mono (meth) acrylic acid ester monomer (EO = 11).

Example  6

The same procedure as in Example 5 was carried out except that the monomer composition of Example 5 was changed to 380 g of 2-ethylhexyl acrylate and 100 g of an alkoxy polyethylene glycol mono (meth) acrylic acid ester monomer (EO = 11).

Example  7

The same procedure as in Example 1 was repeated except that the monomer composition of Example 5 was changed to 330 g of 2-ethylhexyl acrylate and 150 g of alkoxy polyethylene glycol mono (meth) acrylic acid ester monomer (EO = 11).

Example  8

The same procedure as in Example 5 was carried out except that the monomer composition of Example 5 was changed to 280 g of 2-ethylhexyl acrylate and 200 g of an alkoxypolyethylene glycol mono (meth) acrylic acid ester monomer (EO = 11).

Example  9

The same procedure as in Example 1 was carried out except that the monomer composition of Example 1 was changed to 430 g of 2-ethylhexyl acrylate and 50 g of alkoxy polyethylene glycol mono (meth) acrylic acid ester monomer (EO = 23).

Example  10

The same procedure as in Example 9 was carried out except that the monomer composition of Example 9 was changed to 380 g of 2-ethylhexyl acrylate and 100 g of an alkoxy polyethylene glycol mono (meth) acrylic acid ester monomer (EO = 23).

Example  11

The same procedure as in Example 9 was carried out except that the monomer composition of Example 9 was changed to 330 g of 2-ethylhexyl acrylate and 150 g of an alkoxy polyethylene glycol mono (meth) acrylic acid ester monomer (EO = 23).

Example  12

The same procedure as in Example 9 was carried out except that the monomer composition of Example 9 was changed to 280 g of 2-ethylhexyl acrylate and 200 g of an alkoxypolyethylene glycol mono (meth) acrylic acid ester monomer (EO = 11).

Comparative example  One

In the monomer composition of the emulsion acrylic resin 1, 480 g of 2-ethylhexyl acrylate and an alkoxy polyethylene glycol mono (meth) acrylic acid ester monomer were prepared in the same manner as in Example 1 except that the monomer was changed to 0 g.

Comparative example  2

After polymerizing in the same manner as in the monomer composition of Comparative Example 1, an emulsion resin was prepared by adding 10 g of an antistatic agent containing a metal salt (in the form of ethyl alcohol including lithium perchlorate (LiClO ₄ )) to the monomer composition and stirring for 30 minutes.

Comparative example  3

After polymerization in the same manner as in the monomer composition of Comparative Example 1, 10 g of a mixed type antistatic agent (a mixture of polyethyleneoxide and lithium bistrifluoromethane sulfonimide (LiN (SO ₂ CF ₃ ) ₂ ) was added to the monomer composition. Stirred for 30 minutes to prepare an emulsion resin.

Comparative example  4

After polymerizing in the same manner as in the monomer composition of Comparative Example 1, an emulsion resin was prepared by adding 10 g of a water-soluble antistatic agent (fatty acid alkyl ester of polyethylene glycol) to the monomer composition and stirring for 30 minutes.

Manufacture of adhesive coated protective film

1 g of the emulsion acrylic resin 1 was added 1 g of trimethylolpropine tris- (1- (2-methyl) aziridino) propionate as an external crosslinking agent, and stirred for 30 minutes to prepare an adhesive tape specimen.

Adhesive tape specimen manufacturing process was applied to the emulsion acrylic resin on a 38㎛ PET film, and dried for 2 minutes in an oven at 80 ℃ so that the acrylic adhesive resin layer has a thickness of 20㎛. The adhesive tape was laminated by using a release paper, and cut into 1 inch × 100 mm size to prepare a pressure-sensitive adhesive tape to measure the adhesive property.

[Test Example]

The adhesive properties of the emulsion acrylic pressure-sensitive adhesive prepared in Examples and Comparative Examples were measured by the following method, and the results are shown in Table 1 below.

* Surface Resistance Test: The prepared aqueous emulsion acrylic pressure-sensitive adhesive coated PET film was measured for at least four locations for 30 seconds using a Mitsubishi four detection point surface resistance meter, and the average value was used as the surface resistance value.

* Low-speed peeling force test: The adhesive force of the adhesive tape specimen was adhered to JIS Z 0237 and attached to the Sus plate by reciprocating twice at the speed of 300mm / min with a 2kg roller, and aged at room temperature for 1 day. It measured, peeling 180 degree | times at the speed | rate of 300 mm / min.

* Moisture-resistant fouling test: After attaching the adhesive sheet cut to 140mm * 25mm size on the glass plate, put it in a constant temperature and humidity oven, store it at 50 ℃ and 85% for 3 days, and then peel off the adhesive sheet after 10 minutes at room temperature again. The degree to which marks or adhesives appeared on the surface was expressed by the five-point method.

division Surface resistance
(Ω / □) Low Peel Force (gf / in) Moisture-resistant pollution ^{1 )} Example 1 5.6 × 10 ¹² 45 0 Example 2 4.8 × 10 ¹² 20 0 Example 3 2.1 × 10 ¹¹ 33 0 Example 4 2.0 × 10 ¹⁰ 15 One Example 5 4.3 × 10 ¹² 55 × Example 6 1.3 × 10 ¹¹ 32 × Example 7 7.6 × 10 ¹⁰ 30 × Example 8 5.9 × 10 ¹⁰ 39 × Example 9 5.7 × 10 ¹¹ 31 0 Example 10 8.5 × 10 ¹¹ 44 0 Example 11 2.4 × 10 ¹¹ 61 One Example 12 4.4 × 10 ¹¹ 43 2 Comparative Example 1 Over range 46 0 Comparative Example 2 7.0 × 10 ¹² 23 5 Comparative Example 3 5.2 × 10 ¹² 78 5 Comparative Example 4 1.3 × 10 ⁹ 32 5

1) 0-5: The lower the score, the less contamination of the substrate when peeling off the protective film.

Emulsion acrylic pressure-sensitive adhesive prepared using an acrylic monomer containing an alkoxypolyalkylene glycol mono (meth) acrylic acid ester monomer according to an embodiment of the present invention does not include this or compared to the pressure-sensitive adhesive using a conventional antistatic agent It has excellent stain resistance and hardly causes contamination on the substrate when the protective film is peeled off, and also has low peeling force.

Claims (17)

An emulsion acrylic resin formed by polymerizing an acrylic monomer containing an alkoxypolyalkylene glycol mono (meth) acrylic acid ester represented by the following formula (1).
[Formula 1]

In Chemical Formula 1
R ¹ is a hydrogen atom or a methyl group,
R ² O may be one or two or more oxyalkylenes having 2 to 4 carbon atoms, and in the case of two or more, may be added in a block or random phase,
R ³ is an alkyl group having 1 to 4 carbon atoms,
m is an integer of 5-50 in the average added mole number of an oxyalkyl group. The method of claim 1,
The acrylic monomer is an emulsion acrylic resin, characterized in that 5 to 50 parts by weight based on the total weight parts constituting the emulsion acrylic resin. i) 80 to 99.8% by weight of at least one selected from the group consisting of alkyl acrylates, alkyl methacrylates, acrylic monomers including alkylene glycols, allyl esters, vinyl esters, unsaturated acetates and unsaturated nitriles;
ii) 0.1 to 10% by weight of unsaturated carboxylic acid, hydroxyl-containing unsaturated monomer or mixtures thereof; And
iii) 0.1 to 10% by weight of the internal crosslinking agent; emulsion acrylic resin formed by polymerizing a monomer mixture comprising a. The method of claim 3,
The acrylic monomer is an emulsion acrylic resin, characterized in that the alkoxypolyalkylene glycol mono (meth) acrylic acid ester represented by the following formula (1).
[Formula 1]

In Chemical Formula 1
R ¹ is a hydrogen atom or a methyl group,
R ² O may be one or two or more oxyalkylenes having 2 to 4 carbon atoms, and in the case of two or more, may be added in a block or random phase.
R ³ is an alkyl group having 1 to 4 carbon atoms,
m is an integer of 5-50 in the average added mole number of an oxyalkyl group. The method of claim 3,
The alkyl acrylate is methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, heptyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate and isodecyl acrylate Emulsion acrylic resin, characterized in that at least one selected from the group consisting of a rate. The method of claim 3,
The alkyl methacrylate is methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, t-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, 2 Emulsion acrylic resin, characterized in that at least one selected from the group consisting of ethylhexyl methacrylate, octyl methacrylate, decyl methacrylate, dodecyl methacrylate and isobornyl methacrylate. The method of claim 3,
Emulsion acrylic resin, characterized in that at least one selected from the group consisting of acrylic acid, itaconic acid, maleic acid, fumaric acid, methacrylic acid and ethyl methacrylic acid. The method of claim 3,
The hydroxyl group-containing unsaturated monomer is 1 from the group consisting of hydroxymethyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate and 2-hydroxypropyl methacrylate. Emulsion acrylic resin, characterized in that more than one species selected. The method of claim 3,
The internal crosslinking agent is allyl methacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, hexanediol ethoxylate diacrylate, ethylene glycol dimethacrylate , Hexanediol ethoxylate diacrylate, hexanediol propoxylate diacrylate, neopentyl glycol ethoxylate diacrylate, neopentyl glycol propoxylate diacrylate, trimethyl propane ethoxylate triacrylate, trimethyl propane Emulsion, characterized in that at least one selected from the group consisting of propoxylate triacrylate, pentaerythritol ethoxylate triacrylate, pentaerythritol propoxylate triacrylate, vinyltrimethoxysilane and divinylbenzene Acrylic water G. The method of claim 3,
The emulsion acrylic resin, characterized in that the acidity of the emulsion acrylic resin is 4 to 9. The method of claim 3,
Emulsion acrylic resin, characterized in that the glass transition temperature of the emulsion acrylic resin is -60 to 0 ℃. The method of claim 3,
Emulsion acrylic resin, characterized in that the gel content of the emulsion acrylic resin is 50% by weight or more. a) i) at least 80 to 99.8% by weight of at least one selected from the group consisting of alkyl acrylates, alkyl methacrylates, acrylic monomers including alkylene glycols, allyl esters, vinyl esters, unsaturated acetates and unsaturated nitriles; ii) 0.1 to 10% by weight of unsaturated carboxylic acid, hydroxyl-containing unsaturated monomer or mixtures thereof; And iii) 0.1 to 10% by weight of an internal crosslinking agent, wherein the monomer mixture comprises at least one selected from the group consisting of surfactants, buffers, initiators, reducing agents, electrolytes, thickeners, wetting agents and antifoaming agents. Adding an aqueous material to prepare an emulsion; And
b) a method of producing an emulsion acrylic resin, comprising the step of polymerizing the emulsion to prepare an acrylic emulsion. The method of claim 13,
The water-soluble substance is a method for producing an emulsion acrylic resin, characterized in that 0.1 to 20 parts by weight based on 100 parts by weight of the monomer mixture. Emulsion acrylic resin according to claim 1 or 3; And
An emulsion acrylic pressure-sensitive adhesive comprising an external crosslinking agent. 16. The method of claim 15,
Emulsion acrylic pressure-sensitive adhesive, characterized in that 0.5 to 5 parts by weight of the external crosslinking agent with respect to 100 parts by weight of the emulsion acrylic resin. A protective film formed by applying the emulsion acrylic pressure-sensitive adhesive according to claim 15 on one or both sides of the film.