KR101177249B1 - Removable Pressure Sensitive Adhesive Of Acrylic Emulsion Type And Method For Preparing The Same - Google Patents

Abstract

The present invention relates to a re-peelable acrylic pressure-sensitive adhesive and a method for producing the same, and more specifically, to (A) 70 to (meth) acrylic acid ester monomer having an alkyl group having 1 to 14 carbon atoms, based on 100 wt% of the following monomers and crosslinking agents. 96.5 weight percent; (B) 0.5 to 27% by weight of at least one member selected from the group of monomers having a carboxyl group, a monomer having a hydroxyl group, a monomer having an epoxy group, a monomer having a vinyl ester group, and a monomer having a cyano group; And (C) 0.6 to 3% by weight of a crosslinking agent containing 5 to 13 alkylene oxide groups and having an acrylate group or a vinyl group. The present invention relates to a re-peelable acrylic pressure-sensitive adhesive and a method for producing the same.
According to the present invention, the water-based adhesive is environmentally friendly, has excellent temperature and aging adhesiveness and dimensional stability, and has high adhesive force close to the permanent adhesive, and has excellent removability. In addition, there is an effect of providing a re-peelable acrylic pressure-sensitive adhesive and its manufacturing method that can be widely used in products related to automotive, printing, decorative pressure-sensitive adhesive sheet.

Description

Removable Pressure Sensitive Adhesive Of Acrylic Emulsion Type And Method For Preparing The Same}

The present invention relates to a re-peelable acrylic pressure-sensitive adhesive and a method for manufacturing the same, and more particularly, it is environmentally friendly as a water-based pressure-sensitive adhesive, excellent at room temperature and aging adhesiveness and dimensional stability, high adhesive strength close to the permanent adhesive In addition, the present invention relates to a re-peelable acrylic pressure-sensitive adhesive and its manufacturing method which have excellent removability and can be widely used in products related to outdoor / indoor advertisement, vehicle, printing, and decorative pressure-sensitive adhesive sheets.

Re-peelable pressure-sensitive adhesive means a pressure-sensitive adhesive that can be easily removed when the adhesive is attached to the substrate and does not leave stains or debris.

The adhesive sheet to which the re-peelable adhesive is applied to one surface of the substrate layer is subjected to graphic printing of the substrate layer by using an inkjet printer or an airbrush printer, and then a POP display, a plane advertisement or bus wrapping of a bus or taxi, or a window or floor. It is attached to and used for advertising purposes.

Since the pressure sensitive adhesive sheet should be used not only indoors but also outdoors, it is necessary to design the glass transition temperature (Tg) at a low temperature of -40 ° C. or lower in order to exhibit sufficient workability and adhesive properties at low temperatures. In addition, since it may be attached to irregular or curved surfaces depending on the purpose of use, and may be attached for as few months or as long as two years, the adhesive applied to the adhesive sheet should have excellent adhesive force, and the adhesive sheet maintains its original size. The dimensional stability, which is a characteristic to be and the weather resistance to maintain the physical properties during long-term storage is required.

In particular, the re-peelable pressure-sensitive adhesive is important to remove the adhesive after use (re-peelability) is almost eliminated. In most cases, if the re-peelability and dimensional stability is improved, the adhesive properties are often poor. Therefore, re-peelable pressure sensitive adhesives generally have lower adhesive properties than permanent pressure sensitive adhesives that have residues upon removal.

In order to improve the physical properties of the re-peelable pressure-sensitive adhesive, it is necessary to control the appropriate molecular structure such as components, cross-linking density, molecular weight and molecular weight distribution of the pressure-sensitive adhesive. Known.

U.S. Patent No. 5240989 describes a re-peelable acrylic pressure sensitive adhesive having a glass transition temperature (Tg) of -50 to -55 ° C using a multifunctional diacrylate crosslinking agent having several functional groups such as hexanediol diacrylate. In the present disclosure, in order for the pressure-sensitive adhesive to exhibit re-peelability, it is described that the resin should have a certain level of gel content, and for this purpose, it is described that the crosslinking agent is used at 0.1 to 0.3 parts by weight.

U.S. Patent No. 6586510 describes an acrylic pressure-sensitive adhesive whose re-peelability is controlled by using 0.01 to 1 part by weight of a crosslinkable monomer having multiple functional groups such as allyl methacrylate, diallyl maleate or ethylene glycol diacrylate. It is starting.

US Patent Publication No. 2006-0036027 (published Feb. 16, 2006) discloses a re-peelable pressure-sensitive adhesive resistant to a plasticizer using 0.3 to 0.6 parts by weight of a crosslinking agent such as diallyl maleate, allyl acrylate, allyl methacrylate, and the like. .

However, the related arts do not satisfy re-peelability, room temperature and aging adhesiveness at the same time.

The present invention is environmentally friendly as a water-based adhesive, excellent in room temperature and aging adhesiveness and dimensional stability, has a high adhesive strength close to the permanent adhesive, and excellent removability, for outdoor / indoor advertising, vehicle An object of the present invention is to provide a re-peelable acrylic pressure-sensitive adhesive which can be widely used in products related to printing, decorative pressure-sensitive adhesive sheets, and a method of manufacturing the same.

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 (A) 70 to 96.5% by weight of (meth) acrylic acid ester monomer having an alkyl group having 1 to 14 carbon atoms based on 100% by weight of the following monomers and crosslinking agents; (B) 0.5 to 27% by weight of at least one member selected from the group of monomers having a carboxyl group, a monomer having a hydroxyl group, a monomer having an epoxy group, a monomer having a vinyl ester group, and a monomer having a cyano group; And (C) 0.6 to 3% by weight of a crosslinking agent containing 5 to 13 alkylene oxide groups, and having an acrylate group or a vinyl group.

According to the present invention, the water-based adhesive is environmentally friendly, has excellent temperature and aging adhesiveness and dimensional stability, and has high adhesive force close to the permanent adhesive, and has excellent removability. In addition, there is an effect of providing a re-peelable acrylic pressure-sensitive adhesive and its manufacturing method that can be widely used in products related to automotive, printing, decorative pressure-sensitive adhesive sheet.

Hereinafter, the present invention will be described in detail.

The present inventors prepared a re-peelable acrylic emulsion pressure-sensitive adhesive that can satisfy the tackiness, dimensional stability and re-peelability (characteristics that do not leave residue after removal) by adjusting the content and chain length of the crosslinking agent containing an alkylene oxide group. It was confirmed that it can, and based on this, the present invention was completed.

The re-peelable acrylic pressure sensitive adhesive composition of the present invention comprises (A) 70 to 96.5% by weight of (meth) acrylic acid ester monomer having an alkyl group having 1 to 14 carbon atoms, based on 100% by weight of the following monomers and crosslinking agents; (B) 0.5 to 27% by weight of at least one member selected from the group of monomers having a carboxyl group, a monomer having a hydroxyl group, a monomer having an epoxy group, a monomer having a vinyl ester group, and a monomer having a cyano group; And (C) 0.6 to 3% by weight of a crosslinking agent containing 5 to 13 alkylene oxide groups and having an acrylate group or a vinyl group.

Specific examples of the (meth) acrylic acid ester monomer of (A) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate and 2-ethylhexyl (meth). Acrylate, octyl (meth) acrylate, lauryl (meth) acrylate, and the like, and these may be used alone or in combination of two or more thereof.

The (meth) acrylic acid ester monomer of (A) preferably contains 70 to 96.5% by weight relative to the total 100% by weight of the monomer and crosslinking agent used, if less than 70% by weight can not ensure a satisfactory initial adhesive force, When it exceeds 96.5% by weight, there is a problem in that a residue occurs due to interfacial breakage between the base sheet and the adhesive when the used adhesive sheet is removed.

At least one member selected from the functional group-containing monomer group of (B) is preferably a monomer having an epoxy group, a monomer having a cyano group or a mixture thereof, and may further include a monomer having a vinyl ester group optionally.

The monomer having a carboxyl group in (B) may be maleic anhydride, fumaric acid, crotanic acid, itaconic acid, acrylic acid, methacrylic acid, and the like, and the monomer having the hydroxyl group may be, for example, hydroxyethyl (meth) acrylate or hydride. Hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, hydroxyhexyl (meth) acrylate, hydroxyoctyl (meth) acrylate, hydroxylauryl (meth) acrylate, hydroxypropylene glycol ( Meta) acrylate, etc., the monomer having an epoxy group may be, for example, glycidyl methacrylate, allyl glycidyl ether, and the like, and the monomer having the vinyl ester group may be, for example, vinyl acetate, vinyl propionate, or lauric acid. Vinyl, vinylpyrrolidone, and the like, and the monomer having a cyano group may be Examples may be acrylonitrile, methacrylonitrile and the like.

The at least one member selected from the functional group-containing monomer group of (B) may be 0.5 to 27% by weight, preferably 3 to 25% by weight, more preferably 5 to 100% by weight of the total monomers and crosslinking agents used. To 20% by weight, the cohesive force of the resin is sufficient within this range to ensure the dimensional stability and re-peelability, the glass transition temperature (Tg) is appropriate is not limited to outdoor use of the product.

The crosslinking agent of (C) serves to impart cohesion, dimensional stability and re-peelability to the pressure-sensitive adhesive, and preferably contains 5 to 13 alkylene oxide groups, more preferably 6 to 12, Within this range, room temperature and aging adhesiveness, dimensional stability and re-peelability are all excellent effects.

For reference, the number of the alkylene oxide groups means the average number of alkylene oxide groups included in the crosslinking agent used, and the following examples are shown as the average added mole number of the alkylene oxide.

If the crosslinking agent has less than 5 alkylene oxide groups, the pressure-sensitive adhesive prepared is harder than necessary, and the adhesive properties are greatly reduced. If the alkylene oxide groups are more than 13, the pressure-sensitive adhesive prepared is more flexible than necessary to remove the used adhesive sheet. There is a problem that the interface breaks between the base sheet and the pressure-sensitive adhesive to generate a large residue.

The crosslinking agent of (C) may be specifically polyethylene glycol diacrylate (Polyethylene glycol diacrylate, PEGDA), polypropylene glycol diacrylate (Polypropylene glycol diacrylate, PPGDA) or a mixture thereof.

The crosslinking agent of (C) may be included in the amount of 0.6 to 3% by weight, preferably 0.9 to 2.1% by weight, the temperature and aging tackiness, dimensional stability and re-peelability are excellent in this range have.

The re-peelable acrylic pressure-sensitive adhesive may have a glass transition temperature (Tg) of -55 to -35 ℃, preferably -55 to -40 ℃, within this range sufficient low temperature workability and low temperature adhesive properties for outdoor use This can be exercised.

Method for producing a re-peelable acrylic pressure-sensitive adhesive of the present invention is based on (A) 70 to 96.5% by weight of (meth) acrylic acid ester monomer having an alkyl group having 1 to 14 carbon atoms based on 100% by weight of the following monomers and crosslinking agents; (B) 0.5 to 27% by weight of at least one member selected from the group of monomers having a carboxyl group, a monomer having a hydroxyl group, a monomer having an epoxy group, a monomer having a vinyl ester group, and a monomer having a cyano group; And (C) 0.6 to 3% by weight of a crosslinking agent containing 5 to 13 alkylene oxide groups and having an acrylate group or a vinyl group; to 0.5 parts by weight of a polymerization initiator, to 100 parts by weight of the monomer mixture. It features.

The polymerization initiator is preferably a persulfate of ammonium or an alkali metal, hydrogen peroxide, and the like, and has excellent effects in both room temperature and aging adhesiveness, dimensional stability, and releasability.

The polymerization initiator is preferably used in an amount of 0.2 to 5 parts by weight, more preferably 0.5 to 3 parts by weight, based on 100 parts by weight of the total monomers and crosslinking agents used.

Emulsifiers used in the preparation of the re-peelable acrylic pressure-sensitive adhesive may be generally selected from emulsifiers used in emulsion polymerization, and specific examples thereof include sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium alkylarylnaphthalene sulfate, and dode Anionic emulsifiers such as sodium diphenyl oxide sulfate, polyoxyethylene alkyl ether sodium sulfate, polyoxyethylene alkylphenyl ether sodium sulfate, sodium dioctyl sulfide succinate; Nonionic emulsifiers such as polyoxyethylene nonylphenyl ether, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene fatty acid ester and polyoxyethylene-polyoxypropylene block polymer; Etc., and these can be used individually or in mixture of 2 or more types.

The emulsifier is preferably used in 0.5 to 3 parts by weight based on 100 parts by weight of the total monomer and crosslinking agent used in the polymerization.

The prepared re-peelable acrylic pressure sensitive adhesive may be used as a main component of the pressure-sensitive adhesive, and may be used as a main component of the pressure-sensitive adhesive after being neutralized with an alkaline material as necessary.

The alkaline substance may be an inorganic substance such as hydroxide, chloride, carbonate of monovalent metal or divalent metal; ammonia; Or organic amines and the like.

The re-peelable acrylic pressure sensitive adhesive may further include additives such as a tackifier, an antifoaming agent, a wetting agent, a thickener, a dispersant, an ultraviolet stabilizer, an antioxidant, and a filler, as necessary.

The pressure-sensitive adhesive sheet of the present invention is characterized in that the re-peelable acrylic pressure-sensitive adhesive is applied to one side or both sides of the base sheet.

It is preferable that the applied adhesive is 20-30 micrometers in thickness, but the adhesive force with a base sheet and the dimensional stability of a base sheet are fully ensured within this range.

The base sheet is not particularly limited, but may be PVC, PET, PP, PE, or paper sheet. More specifically, the PVC sheet may have a thickness of 50 to 200 μm manufactured by casting or calendering. Do.

The pressure-sensitive adhesive sheet may be laminated on a pressure-sensitive adhesive coated with a release paper in order to protect the pressure-sensitive adhesive layer, increase storage properties of the product, and ensure smoothness. In this case, the thickness of the release paper is preferably 100 to 200 μm.

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 spirit or scope of the present invention. Such variations and modifications are intended to be within the scope of the appended claims.

[Example]

Example  One

<Production of Acrylic Adhesive>

200 g of distilled water and 1.2 g of sodium alkylarylnapthalene sulfonate (SANS) as a surfactant were injected into a 2 L glass reactor equipped with a stirring vane, a thermometer, a nitrogen gas introduction tube, and a reflux condenser, and the inside of the reaction vessel was stirred with nitrogen. It substituted by and heated up to 70 degreeC under nitrogen atmosphere.

To the reactor was added a solution of 0.4 g of ammonium persulfate as a polymerization initiator in 8 g of distilled water, followed by 520 g of butyl acrylate (BA), 152 g of 2-ethylhexyl acrylate (2-EHA), and acrylonitrile ( AN) 40 g, ethyl acrylate (EA) 80 g and polyethylene glycol diacrylate (average number of moles of ethylene oxide 9 mol, EO molecular weight 400) of 8g mixed with a surfactant and 6.8 g of alkyl aryl naphthalene sulfate as a surfactant And a pre-emulsion in which the solution consisting of 328 g of distilled water was mixed with each other and then emulsified was added dropwise for 4 hours. At this time, a solution in which 7.4 g of ammonium persulfate was dissolved in 149 g of distilled water was simultaneously added to the preemulsion and added dropwise for a total of 4 hours.

After the dropping was completed, a solution of 0.2 g of ammonium persulfate dissolved in 3.2 g of distilled water was added at a time, and maintained at 80 ° C. for 1 hour to complete the reaction of unreacted monomers, and then cooled to room temperature to obtain an acrylic adhesive. Prepared.

28% aqueous ammonia was added to the prepared acrylic pressure-sensitive adhesive to adjust (neutralize) the pH to 7-8.

< Adhesive sheet manufacture>

The neutralized acrylic pressure-sensitive adhesive was applied to a release paper and dried at 110 ° C. for 2 minutes, and then uniformly laminated on one surface of the vinyl chloride resin sheet, which was composed of a release paper-adhesive layer-based sheet and the adhesive layer had a thickness of 20 μm. An adhesive sheet was prepared.

Example  2

Example 1 was carried out in the same manner as in Example 1, except that 12 g of polyethylene glycol diacrylate (average number of moles of ethylene oxide added, 9 moles, EO molecular weight 400) was added.

Example  3

Except that 16g of polyethylene glycol diacrylate (9 moles of ethylene oxide average added mole number, EO molecular weight 400) in Example 1 was carried out in the same manner as in Example 1.

Example  4

Except that in Example 1 8g of polypropylene glycol diacrylate (7 moles of propylene oxide average molar number, PO molecular weight 400) instead of polyethylene glycol diacrylate (9 moles of ethylene oxide average added mole number), was added. It carried out by the same method as 1.

Comparative example  One

In Example 1, except that 4.0g of polyethylene glycol diacrylate (average number of moles of ethylene oxide added, 9 moles, EO molecular weight 400) was added in the same manner as in Example 1.

Comparative example  2

Except that in Example 1 8.0g of polyethylene glycol diacrylate (4.5 mol average ethylene oxide, EO molecular weight 200) was added instead of polyethylene glycol diacrylate (9 mol average ethylene oxide) It carried out by the same method as 1.

Comparative example  3

Except that in Example 1 8.0g of polyethylene glycol diacrylate (average number of moles of ethylene oxide added 13.5 mol, EO molecular weight 600) instead of polyethylene glycol diacrylate (9 moles of ethylene oxide average molar number of 9 moles) was added 8.0 g It carried out by the same method as 1.

Comparative example  4

In Example 1, except that 1.6g of polyethylene glycol diacrylate (average number of moles of ethylene oxide added 9 mol, EO molecular weight 400) was added in the same manner as in Example 1.

Comparative example  5

Example 1 was carried out in the same manner as in Example 1, except that 32 g of polyethylene glycol diacrylate (average number of moles of ethylene oxide added, 9 mol, EO molecular weight 400) was added.

Comparative example  6

In Example 1, except that 8.0 g of hexanediol diacrylate (HDDA) was added instead of polyethylene glycol diacrylate (average number of moles of ethylene oxide 9 mol), the same method as in Example 1 was carried out.

Comparative example  7

In Example 1, except that 8.0 g of allyl methacrylate (AMA) was added instead of polyethylene glycol diacrylate (average number of moles of ethylene oxide 9 moles), and the same method as in Example 1 was carried out.

For reference, the average added mole number (N) of the alkylene oxide included in the crosslinking agent was calculated based on Equation 1 below.

[Equation 1]

N = AO molecular weight / unit AO molecular weight

The AO molecular weight is the number average molecular weight of the alkylene oxide group included in the crosslinking agent (for example, EO molecular weight is the number average molecular weight of ethylene oxide included in the crosslinking agent), and the unit AO molecular weight is the molecular weight of one alkylene oxide group (for example, The unit EO molecular weight is 44).

 [Test Example]

Properties of the pressure-sensitive adhesive sheets prepared in Examples 1 to 4 and Comparative Examples 1 to 7 were measured by the following method, and the results are shown in Table 1 below.

1) How to measure peel strength at room temperature :

The prepared pressure-sensitive adhesive sheet was evaluated at room temperature and aging peel strength by a method according to JIS Z 0237. Specifically, after preparing three specimens with a size of 2.5 cm x 10 cm, they were attached to the surface of stainless steel and 300 mm with a 2 kg roller. Peeling strength was measured by reciprocating five times at a rate of / min, storing at room temperature for one day, and then peeling 180 degrees at a rate of 5 mm / sec.

2) Aging peel strength measurement method :

Aging peel strength was advanced by aging the adhesive sheet prepared as a measure for evaluating the deterioration of the adhesive strength when the adhesive sheet is stored for a long time in a 70 ℃ oven for 3 days. After cooling at room temperature for 30 minutes, three specimens were prepared in a size of 2.5 cm x 10 cm, and then attached to the surface of stainless steel, and then reciprocated five times at a speed of 300 mm / min with a 2 kg roller, and stored at room temperature for one day. After peeling 180 degrees at a rate of 5 mm / sec, the peel strength was measured.

3) dimensional stability (shrinkage) measurement method ;

The prepared pressure-sensitive adhesive sheet was cut into a square having a size of 18 cm x 18 cm and then attached by laminating such that bubbles do not occur on the surface of the aluminum plate. The sheath was cut long in the horizontal and vertical directions with a cutter so that the center portion of the pressure sensitive adhesive sheet had a cross shape, and the sheath spacing (dimension before standing) was measured with a calipers. Then, the cut adhesive sheet was stored in an oven at 80 ° C. for 1 day, and then cooled at room temperature to measure the sheath spacing (dimension after standing). From these results, the dimensional shrinkage percentage (%) was obtained by the following equation. The smaller the spacing of the sheaths after standing, that is, the lower the dimensional shrinkage, the better the dimensional stability of the sheet. The shrinkage rate is 0.5% or less.

&Quot; (2) &quot;

Dimensional shrinkage percentage (%) = <{(Dimension before leaving)-(Dimension after leaving)} / Dimension before leaving> x 100

4) Pollution Measurement Method :

As a measure for evaluating the re-peelability of the pressure-sensitive adhesive, three prepared pressure-sensitive adhesive sheets were prepared in a size of 2.5 cm x 10 cm and then attached to the stainless steel surface. This was left for 3 days in an oven at 70 ℃, taken out at room temperature for 1 day and then peeled off at a rate of 5mm / sec to check the residue remaining on the stainless steel surface. Aim at a state where no residue remains.

division Room temperature peel strength (kgf / in) Aging Peel Strength (kgf / in) Shrinkage (%)
(Standard: within 0.5%) Pollutant
(% Residue) Example 1 1.30 1.05 0.4 0 Example 2 1.18 1.07 0.3 0 Example 3 1.14 1.04 0.3 0 Example 4 1.21 1.02 0.5 0 Comparative Example 1 1.28 1.21 1.0 30 Comparative Example 2 1.31 1.12 0.9 0 Comparative Example 3 1.15 0.97 0.4 100 Comparative Example 4 1.43 1.27 1.6 70 Comparative Example 5 0.99 0.89 0.2 0 Comparative Example 6 0.91 0.56 0.2 0 Comparative Example 7 0.78 0.42 0.1 0

As shown in Table 1, the acrylic pressure-sensitive adhesive (Examples 1 to 4) comprising polyethylene glycol diacrylate (alkylene oxide average added mole number 5 to 13) as a crosslinking agent according to the present invention at 0.6 to 3% by weight, It is excellent in both room temperature and aging peel strength, dimensional stability, and re-peelability compared with the case where the content of the crosslinking agent is out of the range (Comparative Examples 1 to 5) and when other short crosslinking agents are used (Comparative Examples 6 and 7). I could confirm it.

For reference, weather resistance, which is a degree of adhesion performance of the adhesive sheet for a long time, may be evaluated by a change rate (Y) of the adhesive force calculated by Equation 3 below, meaning that the smaller the change rate of the adhesive force, the better the weather resistance.

&Quot; (3) &quot;

Y = {(Fb-Fa) / Fa} x 100

(The Y represents the change rate (-) of the adhesive strength decreases the aging adhesive strength compared to the room temperature adhesive strength, Fb is the aging adhesive strength (kgf / in), Fa represents the room temperature adhesive strength (kgf / in)

When a long crosslinking agent such as polyalkylene glycol diacrylate is included from the calculation of Equation 3 (Examples 1 to 4), the change rate of the adhesive force is within about 20%, and hexanediol diacrylate and allyl meta In the case of including a short crosslinking agent such as acrylate (Comparative Examples 6 and 7), it can be seen that the change rate of the adhesive force is 38% and 46%, respectively. When a long crosslinking agent is applied (Examples 1 to 4), it can be seen that weather resistance is superior to that when a short crosslinking agent is applied (Comparative Examples 6 and 7).

Claims (11)

As the water-based pressure-sensitive adhesive, based on 100% by weight of the total of the following monomers and crosslinking agents,
(A) 70 to 96.5% by weight of (meth) acrylic acid ester monomer having an alkyl group having 1 to 14 carbon atoms;
(B) 0.5 to 27% by weight of at least one member selected from the group of monomers having a carboxyl group, a monomer having a hydroxyl group, a monomer having an epoxy group, a monomer having a vinyl ester group, and a monomer having a cyano group; And
(C) 0.6 to 3% by weight of a crosslinking agent containing 5 to 13 alkylene oxide groups and having an acrylate group or a vinyl group;
Equation 3
&Quot; (3) &quot;
Y = (Fb-Fa) / Fa x 100
(The Y is a change rate (-) of the cohesive force of aging cohesion is reduced compared to room temperature cohesion, Fa is a room temperature cohesion (kgf / in), Fb represents the aging cohesion (kgf / in). The change rate of Y is characterized in that less than 20%
Re-peelable acrylic pressure sensitive adhesive. The method of claim 1,
At least one selected from the functional group-containing monomer group of the above (B) is a monomer having an epoxy group, a monomer having a cyano group, or a mixture thereof.
Re-peelable acrylic pressure sensitive adhesive. The method of claim 1,
The (meth) acrylic acid ester monomer of said (A) is methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate. At least one member selected from the group consisting of octyl (meth) acrylate and lauryl (meth) acrylate.
Re-peelable acrylic pressure sensitive adhesive. The method of claim 1,
The functional group-containing monomer group of the above (B) is maleic anhydride, fumaric acid, crotanic acid, itaconic acid, acrylic acid, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) Acrylate, hydroxyhexyl (meth) acrylate, hydroxyoctyl (meth) acrylate, hydroxylauryl (meth) acrylate, hydroxypropylene glycol (meth) acrylate, glycidyl methacrylate, allyl glyc Characterized in that the soldier consisting of vinyl vinyl acetate, vinyl propionate, vinyl laurate, vinylpyrrolidone acrylonitrile and methacrylonitrile
Re-peelable acrylic pressure sensitive adhesive. The method of claim 1,
At least one selected from the functional group-containing monomer group of the above (B) is 5 to 20% by weight, characterized in that
Re-peelable acrylic pressure sensitive adhesive. The method of claim 1,
The crosslinking agent of (C) is at least one member selected from the group consisting of polyethylene glycol diacrylate and polypropylene glycol diacrylate.
Re-peelable acrylic pressure sensitive adhesive. The method of claim 1,
The crosslinking agent of (C) is characterized in that it is contained in 0.9 to 2.1% by weight
Re-peelable acrylic pressure sensitive adhesive. The method of claim 1,
The re-peelable acrylic pressure sensitive adhesive, the glass transition temperature (Tg) is characterized in that -55 to -35 ℃
Re-peelable acrylic pressure sensitive adhesive. The method of claim 2,
It further comprises a monomer having a vinyl ester group in at least one kind selected from the functional group-containing monomer group of the above (B)
Re-peelable acrylic pressure sensitive adhesive. The pressure-sensitive adhesive sheet formed by applying the re-peelable acrylic pressure-sensitive adhesive of claim 1 to one or both sides of the base sheet. The method of claim 10,
The base sheet is a pressure-sensitive adhesive sheet, characterized in that the PVC, PET, PP, PE or paper sheet.