KR101422655B1 - Removable Water-Based Emulsion Pressure-Sensitive Adhesive And Preparation Method thereof - Google Patents

Abstract

The present invention relates to a curable composition comprising 85 to 99.9% by weight of a (meth) acrylic acid ester monomer having a C ₁ -C ₁₄ alkyl group; And 0.1 to 15% by weight of a monomer mixture having a carboxyl group and / or a hydroxyl group, or a mixture thereof, 0.3 to 1.9 parts by weight of an external crosslinking agent, 15 to 25 parts by weight of a rubber- And 1.1 to 9.9 parts by weight of a plasticizer. The present invention also relates to a method for producing the same.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a removable water-based emulsion pressure-

More particularly, the present invention relates to (A) 85 to 99.9% by weight of a (meth) acrylic acid ester monomer having a C ₁ -C ₁₄ alkyl group; (B) 0.3 to 1.9 parts by weight of an external crosslinking agent, (C) 0.1 to 10 parts by weight of a crosslinking agent, 15 to 25 parts by weight of a rubber-based resin, and (D) 1.1 to 9.9 parts by weight of a plasticizer. The present invention also relates to a method for producing the same.

Pressure-Sensitive Adhesive (PSA) is a semi-solid material with a property of adhering to adherend with a small pressure. It is a viscoelastic material different from adhesive and has basic properties of initial adhesion, cohesion and cohesion. Trademark, advertisement, as well as printing, chemicals, pharmaceuticals, household appliances, automobiles, and stationery.

The pressure-sensitive adhesives can be classified into an acrylic type, a rubber type, a silicone type, an EVA type and the like depending on the monomers used in the production, and can be classified into a solvent type, an emulsion type and a hot-melt type depending on the form.

In the past, most of the pressure sensitive adhesives used in adhesive tapes and adhesive labels were solvent type pressure sensitive adhesives. However, as the demand for environmentally friendly pressure sensitive adhesives increased, interest in and development of the pressureless pressure sensitive adhesives was progressing. And it is going to continue to increase in the future. The solventless pressure-sensitive adhesive is typically polymerized by aqueous emulsion polymerization.

On the other hand, the pressure-sensitive adhesives can be classified into permanent pressure-sensitive adhesives and re-release pressure-sensitive adhesives depending on performance, and re-release pressure-sensitive adhesives are used for temporarily adhering adhesive labels. It should not be transferred to the complex.

Generally, rubber adhesives are more flexible than acrylic pressure sensitive adhesives, so they have the advantage of being excellent in initial adhesive strength. However, there is a problem that it is difficult to control the physical properties of the acrylic rubber adhesives because the residue is left after long periods of leaving or being left at high temperature. On the other hand, And the physical properties can be controlled by the molecular weight, the degree of crosslinking, and the like.

Specifically, U.S. Patent No. 6,586,510 discloses an acrylic pressure-sensitive adhesive having regulated releasability using a crosslinking agent such as allyl methacrylate, diarylate or ethylene glycol diacrylate, but has a problem of low initial adhesion .

On the other hand, in order to improve the flexibility of the pressure-sensitive adhesive, U.S. Patent Publication No. 2008/0090948 uses a plasticizer in combination with a wax and a silicone resin such as polypropylene wax, polyethylene wax, PTFE, paraffin and the like, Thereby causing contamination of the adherend.

Although there are a number of conventional techniques for controlling the physical properties of the acrylic pressure-sensitive adhesive as described above, the acrylic pressure-sensitive adhesives have not been satisfactory in terms of excellent heat resistance, initial adhesion, and no residue.

Therefore, a re-peelable water-based emulsion pressure-sensitive adhesive capable of satisfying excellent heat resistance, initial adhesive strength, re-peeling property, low peeling noise, and no residue is desperately required.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-described problems of the prior art and the technical problems required from the past.

The inventors of the present application have conducted extensive research and various experiments and have found that when a cross-linking agent, a rubber adhesive resin and a plasticizer having a functional group reactive with a water-dispersible acrylic adhesive resin are polymerized at a predetermined ratio, The cohesive force and the adhesive force opposite to each other can be improved at the same time, and the initial adhesive force can also be improved, thereby completing the present invention.

Therefore, the re-peelable aqueous emulsion pressure-

(A) 85 to 99.9% by weight of a (meth) acrylic acid ester monomer having a C ₁ -C ₁₄ alkyl group; And 0.1 to 15% by weight of a monomer having a carboxyl group and / or a hydroxyl group, or a mixture thereof, based on 100 parts by weight of a resin polymerized with a mixture of monomers,

(B) 0.3 to 1.9 parts by weight of an external crosslinking agent,

(C) 15 to 25 parts by weight of a rubber-based resin, and

(D) 1.1 to 9.9 parts by weight of a plasticizer

.

The re-peelable pressure-sensitive adhesive according to the present invention is an aqueous emulsion pressure-sensitive adhesive which does not contain an organic solvent but uses water as a dispersion medium, and thus is eco-friendly and has no discharge of harmful substances to the human body and reacts with functional groups of the acrylic pressure- A rubber-based resin which improves the cohesive strength between the external crosslinking agent and the pressure-sensitive adhesive resin and the initial pressure-sensitive adhesive resin, and a plasticizer which improves the flexibility of the pressure-sensitive adhesive resin are polymerized at a predetermined composition ratio, whereby there is no transfer during use and excellent releasability, initial adhesion and heat resistance Do.

Specifically, the acrylic adhesive resin is composed of a (meth) acrylic acid ester monomer and a monomer having a carboxylic acid and / or a hydroxyl group or a mixture thereof. In this case, a monomer having a (meth) acrylic acid ester monomer, a carboxyl group and / The cohesive force of the acrylic adhesive resin is improved by the chemical bonding between the functional groups of the mixture.

In some cases, the cohesive force may be further enhanced by the chemical bonding between the functional groups of the monomer having carboxyl group and / or hydroxyl group, or a mixture thereof and the internal crosslinking agent, as occasion demands, in order to improve cohesion and re- do.

The (meth) acrylic acid ester monomer having a C ₁ -C ₁₄ alkyl group preferably contains 85 to 99.9% by weight based on 100% by weight of a (meth) acrylic acid ester monomer and a monomer mixture having a carboxyl group and / or a hydroxyl group. If it is less than 85% by weight, satisfactory initial adhesive strength can not be secured, which is not preferable.

In one embodiment of the present invention, C ₁ -C a (meth) acrylic acid ester monomer with ₁₄ alkyl groups, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth (Meth) acrylate, butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl Or more.

The monomer having a carboxyl group and / or a hydroxyl group or a mixture thereof is preferably contained in an amount of 0.1 to 15% by weight based on 100% by weight of a (meth) acrylic acid ester monomer and a monomer mixture having a carboxyl group and / or a hydroxyl group.

If it is less than 0.1% by weight, it can not react with the external crosslinking agent. Therefore, the cohesive force can not be improved. Thus, transferring occurs during peeling and peeling noise becomes large.

The monomer having a carboxyl group may be at least one monomer selected from the group consisting of maleic anhydride, fumaric acid, crotonic acid, itaconic acid, and acrylic acid and methacrylic acid. More specifically, the monomer having a hydroxyl group may be at least one selected from the group consisting of hydroxyethyl ) Acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, hydroxyhexyl (meth) acrylate, hydroxyoctyl (Meth) acrylate, and hydroxypropyl (meth) acrylate.

The (meth) acrylic acid ester monomer, the monomer having a carboxyl group and / or the hydroxyl group, or the mixture thereof may be contained in an amount of up to 5% by weight based on the weight of the (meth) acrylic acid ester monomer, the carboxyl group and / It is preferable that the monomer is contained in an amount of 85 to 99.9% by weight and 0.1 to 10% by weight based on 100% by weight of the monomer having a hydroxyl group and the internal crosslinking agent mixture.

Specific examples of the internal crosslinking agent include allyl methacrylate having an acrylate group or a vinyl group, 1,6-hexanediol diacrylate, ethylene glycol dimethacrylate, polyethylglypoldiacrylate, polypropylene glycol diacrylate , Ethylene glycol diacrylate, ethylene glycol dimethacrylate, hexane dioxyethoxylate diacrylate, hexane diol propoxylate diacrylate, neopentyl glycol ethoxylate diacrylate, neopentyl glycol propoxylate diacrylate Trimethylolpropane triacrylate, trimethylolpropane triacrylate, trimethylolpropane triacrylate, trimethylolpropane triacrylate, trimethylolpropanethoxylate triacrylate, trimethylpropanepropoxylate triacrylate, pentaerythritol ethoxylate triacrylate, and pentaerythritol propoxylate triacrylate, vinyltrimethoxysilane and divinyl Benzene, or a mixture thereof.

In a preferred embodiment of the present invention, the acrylic adhesive resin comprises 97.5 to 99.9% by weight of a (meth) acrylic acid ester monomer, 0.1 to 0.5% by weight of a monomer having a carboxyl group and / or a hydroxyl group or a mixture thereof and 2% An internal crosslinking agent may be included.

The external cross-linking agent may be an organic cross-linking agent or an inorganic cross-linking agent as a chemical cross-linking agent. The external cross-linking agent chemically bonds with the functional group of the acrylic emulsion particle to improve cohesion. The external crosslinking agent is contained in an amount of 0.3 to 1.9 parts by weight based on 100 parts by weight of the acrylic emulsion adhesive resin. When the external crosslinking agent is less than 0.3 part by weight, the cohesive force of the acrylic emulsion adhesive resin is lowered. When the external crosslinking agent is more than 1.9 parts by weight, I do not.

The organic crosslinking agent may be an aziridine crosslinking agent, and the aziridine crosslinking agent is preferably an aziridine crosslinking agent containing tris [([beta] -N-aziridinyl) propionate] represented by the following formula , Specifically, trimethylolpropane tris [([beta] -N-2-methyl-1-aziridinyl) propionate], pentaerythritol tris [ ≪ / RTI >

[Chemical Formula 1]

Wherein R ₁ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and R ₂ is hydroxy or an alkyl group having 1 to 12 carbon atoms.

The inorganic crosslinking agent may be at least one selected from the metal chelating group consisting of metal chelate compounds such as aluminum acetylacetonate, aluminum acetate, zinc acetate, chromium acetate, zinc ammonium carbonate and zirconium ammonium carbonate.

The rubber-based resin chemically bonds with the functional group of the acrylic emulsion resin to improve the cohesive force and improve the initial adhesion.

The rubber-based resin may be contained in an amount of 10 to 50 parts by weight based on 100 parts by weight of the acrylic emulsion pressure-sensitive adhesive resin. If it is less than 10 parts by weight, the initial adhesive strength is lowered, and if it is more than 50 parts by weight, It is not preferable. More preferably 15 to 25 parts by weight.

Specific examples of the rubber-based resin include rubber-based resins such as styrene-butadiene rubber (SBR), butadiene rubber (BR), acrylonitrile-butadiene rubber (NBR), chloroprene rubber (CR), isoprene rubber (IR), isobutylene- IIR), ethylene-propylene rubber (EPR), and ethylene-propylene-diene rubber (EPDM).

The plasticizer improves the tackiness by improving the flexibility of the whole pressure-sensitive adhesive, and can be used within 20 parts by weight based on 100 parts by weight of the acrylic emulsion adhesive resin, and is preferably used in the range of 1.1 to 9.9 parts by weight.

When the amount of the plasticizer is 10 parts by weight or more, contamination to the surface to be adhered and deterioration of the adhesive strength are caused. When the amount is less than 1 part by weight, peeling noise is greatly increased.

The plasticizer is selected from the group consisting of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), diheptyl phthalate (DHP), dioctyl phthalate (DOP), dinonyl phthalate (DNP), diisononyl phthalate ), Diisodecyl phthalate (DIDP), dioctyl terephthalate (DOTP), dioctyl malate (DOM), butyl benzyl phthalate (BBP), dioctyl malate (DOM), butyl benzyl phthalate (TOTM), triisononyl trimellitate (TINTM), trioctyl phosphate (TOP), cresyldiphenyl phosphate (CDP), triaryl phosphate (TAP), dioctyl adipate (DOA), diisononyl adipate (ATCC), acetyl tributyl citrate (ATBC), trioctyl citrate (TEC), tetrabutyl citrate (TEC), tetrabutyl citrate Citrate (TOC), acetyltrioctyl citrate (ATOC), trihexylated Rate (THC), acetyl-tree may be at least one selected from the group consisting of hexyl exemplary tray agent (ATHC), and trimethyl citrate (TMC).

The re-peelable aqueous emulsion pressure-sensitive adhesive according to the present invention,

(A) 85 to 99.9% by weight of a (meth) acrylic acid ester monomer having a C ₁ -C ₁₄ alkyl group; And 0.1 to 15% by weight of a monomer mixture having a carboxyl group and / or a hydroxyl group, or a mixture thereof, 0.1 to 3 parts by weight of a polymerization initiator is added to 100 parts by weight of a resin polymerized with a mixture of monomers comprising (B) 0.3 to 1.9 parts by weight of a crosslinking agent, (C) 15 to 25 parts by weight of a rubber-based resin, and (D) 1.1 to 9.9 parts by weight of a plasticizer.

The monomer mixture may contain at most 5% by weight of an internal crosslinking agent having an acrylate group or a vinyl group, and the polymerization initiator may be at least one selected from persulfate of ammonium or alkali metal and hydrogen peroxide, Weight part is more preferably added.

The emulsifier used in the production of the releasable pressure-sensitive adhesive may be selected from among emulsifiers used in emulsion polymerization. Specific examples thereof include sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium alkylarylnaphthalenesulfate, dodecyldiphenyloxide Anionic emulsifiers such as sodium sulfate, sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkylphenyl ether sulfate and sodium dioctylsulfate succinate, polyoxyethylene nonylphenyl ether, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, Nonionic emulsifiers such as polyoxyethylene fatty acid esters and polyoxyethylene-polyoxypropylene block polymers. These may be used singly or in combination of two or more.

The emulsifier is preferably used in an amount of 0.5 to 3 wt.% Based on 100 parts by weight of a resin polymerized with a mixture of monomers comprising a (meth) acrylic acid ester monomer having a C ₁ -C ₁₄ alkyl group and monomers having a carboxyl group and / or a hydroxyl group, Is preferably used as a part.

The pressure sensitive adhesive prepared by the above method is neutralized with an alkaline substance and then used as a main component of the pressure sensitive adhesive. The alkaline substance may be an inorganic substance such as hydroxide, chloride or carbonate of monovalent metal or divalent metal, ammonia or organic amine, and more preferably ammonia.

The re-peelable aqueous emulsion adhesive according to the present invention can be produced by dispersing an aziridine crosslinking agent, a rubber resin and a plasticizer solution in the neutralized acrylic adhesive resin.

The present invention also provides an adhesive sheet formed by applying the above-mentioned re-peelable aqueous emulsion adhesive onto one surface of a surface paper.

The surface of the sheet may be PVC, PET, PP, PE, paper sheet or the like and is preferably an art paper having a thickness of 50 to 200 쨉 m applied to a plastic surface, a glass surface, a box surface, Do.

The thickness of the pressure-sensitive adhesive layer applied on one surface of the surface paper is preferably 20 to 30 占 퐉. In order to apply and protect the pressure-sensitive adhesive, increase the storage property of the pressure- ) Or clay-coated paper release paper is laminated on the adhesive layer.

Specifically, KRAFT or GLASSINE is preferably used as the paper releasing paper, and the thickness of the releasing paper is preferably 100 to 200 mu m.

The pressure-sensitive adhesive according to the present invention is an aqueous emulsion pressure-sensitive adhesive which does not contain an organic solvent but uses water as a dispersion medium, and thus is environmentally friendly, has no discharge of substances harmful to human body and has an external crosslinking agent which improves cohesion by reacting with functional groups of acrylic pressure- The rubber-based resin for improving the cohesive strength between the adhesive resins and the initial adhesive force, and the plasticizer for improving the flexibility of the adhesive resin are polymerized at a predetermined composition ratio, so that there is no transfer upon removal after use, and the exfoliating property, initial adhesive strength and heat resistance are excellent.

Thus, the re-peelable aqueous emulsion adhesive according to the present invention can be applied to various industrial labels such as cosmetics, medicinal food industry, chemical products, and promotional labels, and can be applied to adhesives for electric and electronic products requiring heat resistance and non- And the like.

Hereinafter, the present invention will be described in further detail with reference to the following examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

≪ Example 1 >

Manufacture of acrylic pressure-sensitive adhesive

200 g of distilled water and 1.2 g of sodium alkylaryl naphthalene sulfonate as an emulsifier were charged into a 2 L glass reactor equipped with a stirrer, a thermometer, a nitrogen gas inlet tube and a reflux condenser, and the inside of the reactor was purged with nitrogen And the temperature was raised to 70 占 폚 in a nitrogen atmosphere.

8 g of a 5% ammonium persulfate (APS) solution was added to the reactor, and then 312 g of butyl acrylate (BA), 481 g of 2-ethylhexyl acrylate (2-EHA), 8 g of acrylic acid (AA) And 0.8 g of allyl methacrylate (AMA), and 6.8 g of sodium alkylaryl naphthalenesulfonate, 360 g of distilled water and 1.6 g of sodium carbonate were mixed with each other to emulsify the preemulsion, . At this time, 68.8 g of a 5% ammonium persulfate solution was added simultaneously with the pre-emulsion, and the solution was added dropwise for a total of 4 hours.

After completion of the dropwise addition, 3.2 g of a 5% ammonium persulfate solution was added at once and maintained at 80 DEG C for 1 hour to complete the reaction of the unreacted monomers. After cooling to room temperature, 28% by weight aqueous ammonia solution was added The pH was adjusted to 8 to prepare an acrylic pressure sensitive adhesive having a solid content of about 55%.

Preparation of plasticizer solution

Acetyl tributyl citrate (ATBC) was selected as a plasticizer. As an emulsifier for dispersing the plasticizer, a solution of 0.55 g of sodium alkylaryl naphthalenesulfonate in 45 g of distilled water was added to 55 g of acetyl tributyl citrate and mixed. Then, a homogenizer was dispersed at a rate of 2500 rpm / min for 5 minutes to prepare a 55% plasticizer solution.

Additive formulation

After 100 g of the neutralized acrylic pressure-sensitive adhesive was taken, 0.275 g (0.5 part by weight based on 100 parts by weight of the monomer and the crosslinking agent) of trimethylolpropane tris [([beta] -N-aziridinyl) propionate as an aziridine cross- , 47.8 g of a 23% solid styrene-butadiene rubber (SBR) solution (20 parts by weight based on 100 parts by weight of the monomer and the crosslinking agent), 5 g of the prepared 55% concentration of the plasticizer solution (100 parts by weight of the monomer and the crosslinking agent 5 parts by weight based on 100 parts by weight of water) were added and mixed for 10 minutes to prepare a releasable pressure-sensitive adhesive.

Production of adhesive sheet

The re-peelable pressure-sensitive adhesive was uniformly applied to a paper release paper having a thickness of 130 5% 탆, dried at 120 캜 for 2 minutes, laminated on one side of the art paper, Was 20 +/- 2 mu m.

≪ Example 2 >

The content of trimethylolpropane tris [([beta] -N-aziridinyl) propionate] as an aziridine crosslinking agent in the additive formulation in Example 1 was adjusted to 0.55 g (1 part by weight per 100 parts by weight of the total of monomer and crosslinking agent ) Was put in the same manner as in Example 1, except that the pressure-sensitive adhesive sheet was changed to a pressure-sensitive adhesive sheet.

≪ Example 3 >

The same procedure as in Example 1 was carried out except that 35.9 g (15 parts by weight based on 100 parts by weight of the monomer and the crosslinking agent) of a 23% solids styrene-butadiene rubber (SBR) To prepare a sheet for an adhesive label.

<Example 4>

The same procedure as in Example 1 was carried out except that 59.8 g (25 parts by weight based on 100 parts by weight of the monomer and the crosslinking agent) of a styrene-butadiene rubber (SBR) solution having a solid content of 23% To prepare a sheet for an adhesive label.

&Lt; Example 5 >

A sheet for an adhesive label was prepared in the same manner as in Example 1, except that 3 g of the plasticizer solution (3 parts by weight based on 100 parts by weight of the monomer and the crosslinking agent) was added during the mixing of the additives in Example 1.

&Lt; Example 6 >

In the preparation of the acrylic pressure-sensitive adhesive in Example 1, 0.8 g of allyl methacrylate (AMA) was not used, and 35.9 g of a 23% solids styrene-butadiene rubber (SBR) solution (total of 100 monomers and crosslinking agents 15 parts by weight based on 100 parts by weight of the total weight of the adhesive label).

&Lt; Example 7 >

In Example 1, 0.275 g of aluminum acetylacetonate (the monomer and the crosslinking agent) were added in place of the aziridine crosslinking agent trimethylolpropane tris [([beta] -N-2-methyl-1-aziridinyl) propionate] 0.5 part by weight based on 100 parts by weight) of the above-mentioned composition was added.

&Lt; Example 8 >

In Example 1, 0.275 g of a zinc ammonium carbonate (monomer and crosslinking agent 100 in total) was used instead of trimethylolpropane tris [([beta] -N-2-methyl-1-aziridinyl) propionate] as an aziridine cross- 0.5 parts by weight based on 100 parts by weight of the total weight of the composition).

&Lt; Comparative Example 1 &

A sheet for an adhesive label was prepared in the same manner as in Example 1, except that 0.11 g of aziridine crosslinking agent (0.2 parts by weight based on 100 parts by weight of the monomer and the crosslinking agent) was added during the mixing of the additives in Example 1 .

&Lt; Comparative Example 2 &

A sheet for an adhesive label was prepared in the same manner as in Example 1, except that 1.1 g of the aziridine crosslinking agent (2 parts by weight based on 100 parts by weight of the total of monomers and crosslinking agent) .

&Lt; Comparative Example 3 &

A sheet for an adhesive label was prepared in the same manner as in Example 1, except that the styrene-butadiene rubber (SBR) solution containing 23% solids was not added during the addition of the additive.

&Lt; Comparative Example 4 &

In the same manner as in Example 1, except that 23.9 g of a styrene-butadiene rubber solution having a solid content of 23% (10 parts by weight based on 100 parts by weight of the monomer and the crosslinking agent) Lt; / RTI &gt;

&Lt; Comparative Example 5 &

Except that 71.7 g of a 23% solids styrene butadiene rubber (SBR) solution (30 parts by weight based on 100 parts by weight of the total of the monomers and the crosslinking agent) was added during the addition of the additive in Example 1, Thereby preparing a sheet for an adhesive label.

&Lt; Comparative Example 6 >

In Example 1, a sheet for an adhesive label was prepared in the same manner as in Example 1, except that the plasticizer solution was not used when the additives were mixed.

&Lt; Comparative Example 7 &

A sheet for an adhesive label was prepared in the same manner as in Example 1, except that 1 g of the plasticizer solution (1 part by weight based on 100 parts by weight of the monomer and the crosslinking agent) was added during the mixing of the additives in Example 1.

&Lt; Comparative Example 8 >

A sheet for an adhesive label was prepared in the same manner as in Example 1, except that 10 g of the plasticizer solution (1 part by weight based on 100 parts by weight of the monomer and the crosslinking agent) was added during the mixing of the additives in Example 1.

&Lt; Comparative Example 9 &

A sheet for an adhesive label was prepared in the same manner as in Example 1, except that the aziridine crosslinking agent, the styrene-butadiene rubber (SBR) solution and the plasticizer solution were not added.

&Lt; Comparative Example 10 &

A sheet for an adhesive label was prepared in the same manner as in Example 1, except that the styrene-butadiene rubber (SBR) solution and the plasticizer solution were not added.

<Experimental Example>

The properties of the sheets for adhesive labels prepared in Examples 1-6 and Comparative Examples 1-10 were measured by the following methods, and the results are shown in Table 1 below.

Adhesion at room temperature (90 ° peel strength ) How to measure:

The sheet for the manufactured adhesive label was evaluated in accordance with the adhesive strength measurement method of KS A 1107. Specifically, five specimens having a size of 2.5 cm x 20 cm were prepared and attached to the glass surface. The specimens were then reciprocated five times at a speed of 300 mm / min with a 2 kg roller, and after 20 minutes, The adhesive strength was measured by delaminating at 90 ° at a speed of 5 mm / sec. The target value was 300 to 500 gf / in.

Initial Tack (Ball Tack) Measuring Method :

The sheet for the adhesive label was evaluated according to the initial adhesive strength measurement method of KS A 1107. Specifically, a ball was rolled over a 10 cm-long adhesive specimen on an inclined surface of 30 ° to measure a ball size when the ball was stopped for 5 seconds or more. The target value was set to ball No. 5 or more.

Heat resistance measurement method :

The prepared sheets for adhesive labeling were prepared with three 2.5 cm x 15 cm specimens and then attached to the outer wall of 500 mL PE bottles. This was stored in an oven at 50 DEG C for 1 hour, then left at room temperature for 3 days, and the state of attaching the sheet to the outer wall was qualitatively evaluated. The target level is aimed at the attached sheet being in close contact with the PE wall without air tunnel or lifting.

◎: No lift, no air tunnel,

○: No lift, but a little air tunnel,

△: The state where there is weak excrement and air tunnel exists,

X: Heavy excited state,

Peeling Noise Measurement Method :

The prepared adhesive label sheet was prepared in a size of 2.5 cm x 15 cm, and then peeled off after attaching it to the glass surface. Separation of peeling noise level from 0 to 4, 0 was evaluated as no noise, 4 was rated as the noisy condition, and the peeling noise was below 1 as the target level.

0: A state where noise is hardly heard,

1: Very weak noise,

2: Weak noise,

3: Strongly audible,

4: Very strong sound,

Ghost measurement method :

Three sheets of the sample for the adhesive label were prepared with a size of 2.5 cm x 15 cm and then attached to the mirror surface. This was stored in an oven at 50 DEG C for 1 hour, then left at room temperature for 3 days, and the attached sheet was peeled from the mirror surface to qualitatively evaluate the residue generated on the mirror surface. The target level was such that there was almost no residual image on the mirror surface when the sheet was peeled off.

[Table 1]

As shown in Table 1, in the case of Example 1-6 in which aziridine crosslinking agent was applied, the cohesive force of the resin was improved as compared with Comparative Example 9 before use, and the after-image was eliminated and the peeling noise was remarkably reduced. It was also confirmed that the amount of the aziridine crosslinking agent to be used was preferably 0.3 to 1.9 parts by weight in consideration of the normal-temperature cohesion, the initial cohesion and the peeling noise (see Comparative Examples 1 and 2). Examples 7 and 8, in which aluminum acetylacetonate and zinc ammonium carbonate were applied, showed similar results to aziridine crosslinking agents.

In addition, in the case of Example 1-6 in which a rubber-based resin was applied to a resin, the room temperature and initial adhesive strength and heat resistance of the resin were greatly improved as compared with Comparative Example 3 which was not applied. However, when the amount exceeds 30 parts by weight (Comparative Example 5) And less than 15 parts by weight (Comparative Example 4). Accordingly, it was confirmed that the amount of the rubber-based resin to be used is preferably 15 to 25 parts by weight in consideration of room temperature and initial adhesion, heat resistance and peeling noise.

On the other hand, in Example 1-6 in which a plasticizer was applied to a resin, peeling noise was improved as compared with Comparative Example 6 before use of a plasticizer. However, room temperature and initial tackiness began to decrease rapidly as the amount of use increased, , The afterimage was found to be significantly lower than when the plasticizer was 5 parts by weight or less. Therefore, it was confirmed that the use amount of the plasticizer is preferably 1.1 to 9.9 parts by weight in consideration of the normal-temperature cohesion, initial adhesion, peeling noise and after-image.

Furthermore, in Example 1-5, in which both the internal crosslinking agent, the external crosslinking agent, the rubber-based resin and the plasticizer solution were applied to the resin, it was confirmed that the resin was improved in terms of room temperature, initial adhesive strength and heat resistance as compared with Comparative Example 10 in which only the external crosslinking agent was applied.

In addition, in Example 6 in which an internal cross-linking agent was not used during polymerization, room temperature and initial adhesive strength were slightly increased as compared with Example 3 in which an internal cross-linking agent was applied, and did not significantly affect other properties such as peeling noise and afterimage.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims (13)

(A) 85 to 99.9% by weight of a (meth) acrylic acid ester monomer having a C ₁ -C ₁₄ alkyl group; And 0.1 to 15% by weight of a monomer having a carboxyl group, or a monomer having a hydroxyl group, or a monomer having a carboxyl group and a hydroxyl group, or a mixture of two or more thereof, based on 100 parts by weight of the resin polymerized with the monomer mixture,
(B) 0.3 to 1.9 parts by weight of an external crosslinking agent,
(C) 15 to 25 parts by weight of a rubber-based resin, and
(D) 1.1 to 9.9 parts by weight of a plasticizer
, Wherein the composition comprises:
The rubber-based resin may be at least one selected from the group consisting of styrene-butadiene rubber (SBR), butadiene rubber (BR), acrylonitrile-butadiene rubber (NBR), chloroprene rubber (CR), isoprene rubber (IR), isobutylene- (EPR), ethylene-propylene rubber (EPR), and ethylene-propylene-diene rubber (EPDM). The re-peelable aqueous emulsion pressure-sensitive adhesive according to claim 1, wherein the external crosslinking agent is an organic crosslinking agent or an inorganic crosslinking agent. 3. The re-peelable aqueous emulsion pressure-sensitive adhesive according to claim 2, wherein the organic crosslinking agent is an aziridine crosslinking agent. The rub-off type aqueous emulsion according to claim 2, wherein the inorganic crosslinking agent is at least one selected from the group consisting of aluminum acetylacetonate, aluminum acetate, zinc acetate, chromium acetate, zinc ammonium carbonate and zirconium ammonium carbonate. adhesive. The method of claim 1 wherein the C ₁ -C a (meth) acrylic acid ester monomer with ₁₄ alkyl groups, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate (Meth) acrylate selected from the group consisting of methyl (meth) acrylate, butyl (meth) acrylate, t- butyl (meth) acrylate, 2-ethylhexyl More than species,
The monomer having a carboxyl group is at least one selected from the group consisting of maleic anhydride, fumaric acid, crotonic acid, itaconic acid, acrylic acid and methacrylic acid,
The monomer having a hydroxyl group may be at least one selected from the group consisting of hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, hydroxyhexyl (meth) acrylate, , Hydroxy lauryl (meth) acrylate, hydroxypropyl glycol (meth) acrylate, and the like. delete The method of claim 1, wherein the plasticizer is selected from the group consisting of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), diheptyl phthalate (DHP), dioctyl phthalate (DOP), dinonyl phthalate (DIP), diisodecyl phthalate (DIDP), dioctyl terephthalate (DOTP), dioctyl malate (DOM), butyl benzyl phthalate (BBP), dioctyl malate (DOM), butyl benzyl phthalate ), Trioctyl trimellitate (TOTM), triisononyl trimellitate (TINTM), trioctyl phosphate (TOP), cresyldiphenyl phosphate (CDP), triaryl phosphate (TAP), dioctyl adipate ), Diisononyl adipate (DINA), diisodecyl adipate (DIDA), triethyl citrate (TEC), tributyl citrate (TBC), acetyl triethyl citrate (ATEC), acetyl tributyl citrate (ATBC), trioctyl citrate (TOC), acetyl trioctyl citrate Wherein the release agent is at least one selected from the group consisting of ATOC, THC, acetyl trihexate, and trimethyl citrate (TMC). The re-peelable aqueous emulsion pressure-sensitive adhesive according to claim 1, wherein the resin (A) further comprises up to 5% by weight of a crosslinking agent having an acrylate group or a vinyl group. (A) 85 to 99.9% by weight of a (meth) acrylic acid ester monomer having a C ₁ -C ₁₄ alkyl group; And 0.1 to 15% by weight of a monomer having a carboxyl group, or a monomer having a hydroxyl group, or a monomer having a carboxyl group and a hydroxyl group, or a mixture of two or more thereof, in an amount of 0.1 to 3 wt% (B) 0.3 to 1.9 parts by weight of an external crosslinking agent, (C) 15 to 25 parts by weight of a rubber-based resin, and (D) 1.1 to 9.9 parts by weight of a plasticizer, Butadiene rubber (IRR), isobutylene-isoprene rubber (IIR), ethylene-propylene rubber (EPR), polybutadiene rubber , And ethylene-propylene-diene rubbers (EPDM). The present invention also provides a method for producing a re-peelable aqueous emulsion pressure-sensitive adhesive. The method of claim 9, wherein the monomer mixture further contains up to 5% by weight of a crosslinking agent having an acrylate group or a vinyl group. The method for producing a re-peelable aqueous emulsion pressure-sensitive adhesive according to claim 9, wherein the polymerization initiator is at least one selected from persulfates of ammonium or alkali metals and hydrogen peroxide. A pressure-sensitive adhesive sheet, characterized in that the pressure-sensitive adhesive according to any one of claims 1 to 5 and 7 to 8 is applied on one surface of a surface paper. The pressure-sensitive adhesive sheet according to claim 12, wherein the surface of the sheet is polyvinyl chloride (PVC), polyethylene terephthalate (PET), polypropylene (PP), polyethylene (PE), or paper sheet.