KR101971649B1 - Base-less double-sided adhesive sheet - Google Patents

Abstract

For example, there is provided an inorganic material double-sided pressure-sensitive adhesive sheet having a good antistatic property and releasability as well as an oligomer-blocking property on a release film itself, as a member for a touch panel of a capacitive type. Sensitive adhesive sheet in which a release film having different peel strengths is laminated on both sides of a pressure-sensitive adhesive layer, wherein the first release film is smaller than the second release film with respect to the peeling force, and at least one release film is a polyester film Sensitive adhesive sheet, which is a release film in which a coating layer containing a conductive compound (A) and a binder polymer (B) is laminated on a support layer and a release layer is laminated on the coating layer.

Description

BASE-LESS DOUBLE-SIDED ADHESIVE SHEET [0002]

The present invention relates to a base-less double-sided pressure-sensitive adhesive sheet, which is excellent in antistatic property, releasability, oligomer blocking property and coating appearance, does not cause peeling electrification at the time of releasing the releasing film, It is possible. Further, after peeling the release film after application of the pressure-sensitive adhesive, the peeling fluctuation with respect to the pressure-sensitive adhesive layer is small, and migration and precipitation of the oligomer into the pressure-sensitive adhesive layer are minimized. The present invention provides a suitable inorganic material double-sided pressure-sensitive adhesive sheet suitable for various applications such as, for example, for the production of a liquid crystal polarizing plate and for the production of a capacitive touch panel, through a pressure-sensitive adhesive layer.

BACKGROUND ART [0002] Conventionally, various types of pressure-sensitive adhesive sheets are known in which objects are adhered to each other, and an inorganic material double-faced pressure-sensitive adhesive sheet is exemplified as one of the pressure-sensitive adhesive sheets. The inorganic material double-faced pressure-sensitive adhesive sheet has a laminated structure in which a light-releasing film having relatively low peeling force on both sides of the pressure-sensitive adhesive layer and a heavy-weight film having a relatively high peeling force are laminated. After removing the both- , And a pressure-sensitive adhesive layer having no supporting substrate.

As a method of using the inorganic material double-faced pressure-sensitive adhesive sheet, the light-exfoliating film is first peeled off, the one surface of the exposed pressure-sensitive adhesive layer is adhered to the object surface of the other object to be adhered, There is exemplified a processing step in which the other surface of the pressure-sensitive adhesive layer is adhered to different object surfaces, thereby adhering the objects to each other.

In recent years, the inorganic material double-faced pressure-sensitive adhesive sheet has attracted attention that its workability is good, and its applications are widened, and it is also used in members for various optical uses, such as mobile phones. Particularly, in a capacitive touch panel, the application as an information terminal is rapidly expanded by a multi-touch operation in which a screen is operated with two fingers. As compared with the low resistance film type, the capacitive touch panel tends to have a thick step of printing in terms of the structure. Therefore, it has been proposed to thicken the pressure sensitive adhesive layer to solve the step of printing. In the case where the pressure-sensitive adhesive layer is made thick, there is a case that when the release film is peeled, a part of the pressure-sensitive adhesive layer adheres to the release film or bubbles are mixed into the pressure- Therefore, when the inorganic material double-faced pressure-sensitive adhesive sheet is used in optical applications, not only inorganic double-faced pressure-sensitive adhesive sheets but also release films to be combined are required to have a stricter and more highly- have.

On the other hand, when using the release film, peeling electrification may occur when peeling off from the pressure-sensitive adhesive layer, and as a result, there arises a problem that defective product due to adhesion or incorporation of foreign matters occurs at the processing site . Therefore, the antistatic measures by the equipment response in the manufacturing process alone are not necessarily sufficient, and the antistatic treatment from the release film itself is strongly desired. Further, in the release film provided with the releasing layer of the middle-bust type, there was a tendency that the releasing film was deteriorated when it was peeled off after a long-term adhesion with the pressure-sensitive adhesive layer. As in the present invention, in applications such as adhering a releasing film through a pressure-sensitive adhesive layer, when the ratio of the peeling force is out of a desired range, it is difficult to peel off In some cases.

Publication No. 2011-189589 Publication No. 2011-245739 Publication No. 2011-224896 Publication No. 2011-224904 Publication No. 2012-25030 Publication No. 2012-184327 Publication No. 2012-207166

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a touch panel member of a capacitive type, which is excellent in antistatic property and releasability, and has an oligomer- To provide a pressure-sensitive adhesive sheet.

DISCLOSURE OF THE INVENTION The present inventors have intensively studied in view of the above circumstances, and as a result, they found that the above problems can be solved easily with an inorganic material double-sided pressure-sensitive adhesive sheet having a specific constitution, and have completed the present invention.

That is, the gist of the present invention is an inorganic material double-sided pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer and a release film having different peel strengths laminated on both sides of the pressure-sensitive adhesive layer, wherein the first release film is smaller than the second release film, Wherein the release film is a release film in which a coating layer containing a conductive compound (A) and a binder polymer (B) is laminated on a polyester film and a release layer is laminated on the coating layer, Lt; / RTI >

The inorganic material double-faced pressure-sensitive adhesive sheet of the present invention is excellent in antistatic property, releasability and oligomer-blocking property in a release film as a constituent material thereof. Therefore, for example, And is suitable as an adhesive sheet.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic sectional view showing an inorganic material double-faced adhesive sheet according to an embodiment of the present invention. Fig.

Hereinafter, the present invention will be described in detail.

The polyester film constituting the first and second release films in the present invention may have a single layer structure or a multilayer structure. For example, in addition to the two-layer structure and the three-layer structure, Or more, and is not particularly limited.

The polyester used in the polyester film in the present invention may be homopolyester or copolymerized polyester. When it is composed of homopolyester, it is preferable that it can be obtained by polycondensing an aromatic dicarboxylic acid and an aliphatic glycol. Examples of the aromatic dicarboxylic acid include terephthalic acid and 2,6-naphthalenedicarboxylic acid. Examples of the aliphatic glycol include ethylene glycol, diethylene glycol, 1,4-cyclohexanedimethanol and the like. Representative polyesters include polyethylene terephthalate (PET) and the like. On the other hand, examples of the dicarboxylic acid component of the copolyester include one or two kinds of isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, adipic acid, sebacic acid, oxycarboxylic acid And examples of the glycol component include one or more of ethylene glycol, diethylene glycol, propylene glycol, butanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, and the like. In either case, the polyester referred to in the present invention refers to a polyester such as polyethylene terephthalate whose ethylene terephthalate unit is usually at least 60 mol%, preferably at least 80 mol%.

In the present invention, the polyester layer is preferably blended with the main purpose of imparting lubricity. The type of the particles to be incorporated is not particularly limited as long as the particles can impart lubricity, and specific examples thereof include silica, calcium carbonate, magnesium carbonate, barium carbonate, calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, Titanium and the like. Heat resistant organic particles described in Japanese Patent Publication No. 59-5216 and Japanese Patent Application Laid-Open No. 59-217755 may also be used. Examples of the heat-resistant organic particles include thermosetting urea resin, thermosetting phenol resin, thermosetting epoxy resin, and benzoguanamine resin. In the polyester production process, precipitated particles in which a part of metal compounds such as catalysts are precipitated and finely dispersed can be used.

On the other hand, the shape of particles to be used is not particularly limited, and any of spherical, massive, rod-shaped, and flat-shaped shapes may be used. The hardness, specific gravity, color, and the like are not particularly limited. These series of particles may be used in combination of two or more as necessary.

The average particle diameter of the particles used is usually in the range of 0.01 to 3 占 퐉, preferably in the range of 0.01 to 1 占 퐉. When the average particle diameter is less than 0.01 탆, the particles easily aggregate and the dispersibility may be insufficient. On the other hand, when the average particle diameter exceeds 3 탆, the surface roughness of the film becomes too coarse, There is a case where a problem such as a case of being made to be opened is caused.

The content of the particles in the polyester layer is usually in the range of 0.001 to 5 wt%, and preferably in the range of 0.005 to 3 wt%. When the content of the particles is less than 0.001% by weight, the film may be insufficiently lubricated. When the content is more than 5% by weight, transparency of the film may be insufficient.

The method of adding particles to the polyester layer is not particularly limited, and conventionally known methods can be employed. For example, they may be added at any stage of producing the polyester constituting each layer, but preferably the polycondensation reaction may be carried out after the esterification step or the transesterification reaction.

Also, a method of blending a slurry of particles dispersed in ethylene glycol or water or the like with a polyester raw material by using a vented kneading extruder, or a method of blending dried particles and a polyester raw material by using a kneading extruder or the like .

In addition to the above-mentioned particles, conventionally known antioxidants, antistatic agents, heat stabilizers, lubricants, dyes, pigments and the like may be added to the polyester film in the present invention.

The thickness of the polyester film constituting the first release film and the second release film of the present invention is not particularly limited as long as the film can be formed into a film, but is usually 25 to 250 탆, preferably 38 to 188 탆, more preferably Lt; RTI ID = 0.0 > 125 < / RTI >

Next, production examples of the polyester film in the present invention will be described in detail, but the present invention is not limited to the following production examples.

First, a method of obtaining an unstretched sheet by cooling and solidifying the molten sheet extruded from the die using the above-mentioned polyester raw material in a cooling roll is preferable. In this case, in order to improve the planarity of the sheet, it is necessary to enhance the adhesion between the sheet and the rotary cooling drum, and the electrostatic adhesion method and / or the liquid application adhesion method are preferably adopted. Subsequently, the obtained non-stretched sheet is stretched in the biaxial direction. In this case, first, the unstretched sheet is stretched in one direction by a roll or tenter type stretching machine. The stretching temperature is usually 70 to 120 占 폚, preferably 80 to 110 占 폚, and the stretching magnification is usually 2.5 to 7 times, preferably 3.0 to 6 times. Next, the stretching temperature orthogonal to the stretching direction at the first stretching is usually 70 to 170 占 폚, and the stretching ratio is usually 3.0 to 7 times, preferably 3.5 to 6 times. Subsequently, heat treatment is performed at 180 to 270 ° C under relaxation or within 30% to obtain a biaxially oriented film. In the above stretching, a method of performing unidirectional stretching in two or more stages can be employed. In this case, it is preferable that the stretching ratio in this direction is finally set in the above range.

The simultaneous biaxial stretching method can be employed for the production of the polyester film in the present invention. The simultaneous biaxial stretching method is a method of orienting the unstretched sheet simultaneously in the machine direction and the width direction under the temperature-controlled condition at 70 to 120 캜, preferably 80 to 110 캜, and the stretching magnification 4 to 50 times, preferably 7 to 35 times, and more preferably 10 to 25 times. Subsequently, heat treatment is performed at a temperature of 170 to 250 ° C under relaxation or within 30% to obtain a stretched oriented film. For the simultaneous biaxial stretching apparatus employing the stretching method described above, a conventionally known stretching method such as a screw method, a pentagonal method, and a linear driving method can be employed.

In addition, a so-called coating stretching method (in-line coating) in which the film surface is treated during the stretching process of the above-mentioned polyester film can be carried out. When the coating layer is provided on the polyester film by the coating stretching method, the coating layer can be coated simultaneously with the stretching, and the thickness of the coating layer can be made thinner depending on the stretching magnification. As a result, can do.

The coating layer constituting the release film of the present invention will be described.

The coating layer constituting at least one release film in the present invention contains the conductive compound (A) and the binder polymer (B) in order to improve the antistatic property and the oligomer precipitation preventing property. Such a coating layer may be laminated on any release film having a low peeling force or a high peeling force. It may also be laminated on both release films.

As the conductive compound (A), a polymer obtainable by singly or copolymerizing a thiophene or a thiophene derivative is preferable, and in particular, a compound doped with another anion compound to a compound comprising a thiophene or thiophene derivative, Having an anion group and being self-doped, exhibits excellent conductivity and is suitable. As such a compound (A), for example, those obtained by polymerizing the compound of the following formula (1) or (2) in the presence of a polyanion can be exemplified.

[Formula 1]

In the formula (1), R ¹ and R ² each independently represent a hydrogen atom, an aliphatic hydrocarbon group of 1 to 12 carbon atoms, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group, and examples thereof include a methyl group, Propyl group, butyl group, cyclohexylene group, benzene group and the like. In the above formula (2), n is an integer of 1 to 4.

In the release film of the present invention, it is preferable to use a polythiophene or a polythiophene derivative having a structural formula represented by the formula (2). For example, in the formula (2), n = 1 (methylene group) = 2 (ethylene group), and n = 3 (propylene group). Particularly preferred among them are ethylene group compounds of n = 2, i.e., poly-3,4-ethylenedioxythiophene. As the polythiophene or polythiophene derivative, for example, a compound in which a functional group is bonded at 3 and 4 positions of a thiophene ring is exemplified. As described above, a compound in which oxygen atoms are bonded to carbon atoms at 3 and 4 positions is preferable. For a compound having a structure in which a carbon atom or a hydrogen atom is directly bonded to the corresponding carbon atom, it may not be easy to make the coating liquid water-soluble.

In the polyester film of the present invention, it is preferable that the coating layer contains a composition comprising the polythiophene and the polyanion, or a composition comprising the polythiophene derivative and the polyanion.

Examples of the polyanion used in the polymerization include poly (meth) acrylic acid, polymaleic acid, and polystyrenesulfonic acid. These acids may be partly or wholly neutralized.

As a method for producing such a polymer, for example, the method described in JP-A-7-90060 can be adopted.

In the present invention, a particularly preferred embodiment includes n = 2 in the compound of the formula (2) and polystyrene sulfonic acid as the polyanion.

The coating layer constituting the release film of the present invention contains the conductive compound and the binder polymer as essential requirements.

The binder polymer (B) constituting the coating layer in the present invention had a number average molecular weight (Mw) determined by Gel Permeation Chromatography (GPC) measurement according to a polymer compound stability evaluation block scheme (sponsored by the Chemical Council, (Mn) of 1000 or more, and is defined as having film-forming property.

The binder polymer (B) constituting the coating layer in the present invention may be either a thermosetting resin or a thermoplastic resin as long as it is compatible or dispersible with thiophene or thiophene derivatives. For example, polyesters such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate; Polyimides such as polyimide and polyamideimide; Polyamides such as polyamide 6, polyamide 6,6, polyamide 12 and polyamide 11; Fluorine resins such as polyvinylidene fluoride, polyvinyl fluoride, polytetrafluoroethylene, ethylene tetrafluoroethylene copolymer, and polychlorotrifluoroethylene; Vinyl resins such as polyvinyl alcohol, polyvinyl ether, polyvinyl butyral, polyvinyl acetate and polyvinyl chloride; Epoxy resin; Oxetane resin; Xylene resin; Aramid resin; Polyimide silicon; Polyurethane ; Polyurea; Melamine resin; Phenolic resin; Polyethers; Acrylic resins, and copolymers thereof.

The mixing ratio of the conductive compound (A) in the coating layer is usually in the range of 10 to 90 wt%, preferably 20 to 80 wt%. If the content is less than 10% by weight, the antistatic property and the oligomer precipitation preventing property may be insufficient. On the other hand, when it exceeds 90% by weight, the antistatic property and the oligomer precipitation preventing property are saturated, and a remarkable effect may not be obtained even when the amount is increased. Also, the transparency of the coated film is insufficient.

Such a binder polymer (B) may be dissolved in an organic solvent, or a functional group such as a sulfo group or a carboxyl group may be adhered to be aqueous solution. If necessary, a curing agent such as a crosslinking agent and a polymerization initiator, a polymerization promoter, a solvent, a viscosity controlling agent and the like may be used in combination with the binder polymer (B).

Of the above-mentioned binder polymer (B), since it is easy to mix at the time of preparing the coating liquid, it is selected from a polyester resin, an acrylic resin and a polyurethane resin. Of these, at least one kind is preferable. Particularly, a polyurethane resin is preferable.

The polyester resin used in the present invention is defined as a polyester on the line having a dicarboxylic acid component and a glycol component as constituent components. As the dicarboxylic acid component, terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4-diphenyldicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, adipic acid, sebacic acid, phenylindanicarboxylic acid, dimer Acid, and the like. Two or more of these components may be used. In addition, unsaturated polybasic acids such as maleic acid, fumaric acid and itaconic acid, and hydroxycarboxylic acids such as p-hydroxybenzoic acid and p- (beta -hydroxyethoxy) benzoic acid may be used in small amounts in combination with these components. The amount of the unsaturated polybasic acid component or the hydroxycarboxylic acid component is usually 10 mol% or less, preferably 5 mol% or less.

Examples of the glycol component include ethylene glycol, 1,4-butanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, xylylene glycol, (Alkylene oxide adducts of bisphenol A, hydrogenated bisphenol A alkylene oxide adducts, and the like), and the like can be given as examples of the alkylene oxide adducts of bisphenol A, polyphenylene oxide adducts, have. Two or more of these may be used.

Among these polyol components, ethylene glycol, an ethylene oxide adduct of bisphenol A, a propylene oxide adduct, and 1,4-butanediol are preferable, and an ethylene oxide adduct or an adduct of propylene oxide of ethylene glycol, bisphenol A is preferable. The polyester resin may be copolymerized with a compound having a sulfonic acid group or a compound having a carboxylic acid group in a small amount (to some extent) in order to facilitate aqueous liquefaction. Examples of the compound having a sulfonic acid group include 5-sodium sulfoisophthalic acid, 5-ammonium sulfoisophthalic acid, 4-sodium sulfoisophthalic acid, 4-methylammonium sulfoisophthalic acid, 2- Sulfonic acid alkali metal salt type or sulfonic acid amine salt type compounds such as 5-potassium sulfoisophthalic acid, 4-potassium sulfoisophthalic acid, 2-potassium sulfoisophthalic acid and sodium sulfosuccinic acid.

Examples of the compound having a carboxylic acid group include trimellitic anhydride, trimellitic acid, pyromellitic anhydride, pyromellitic acid, trimesic acid, cyclobutanetetracarboxylic acid, dimethylolpropionic acid, etc., and mono alkali metal salts thereof . Further, the free carboxyl group is reacted with an alkali metal compound or an amine compound after copolymerization to form a carboxylic acid base. A polyester obtained by appropriately selecting one or more of these compounds and synthesizing them by a usual polymerization reaction can be used.

The glass transition temperature (hereinafter abbreviated as Tg in some cases) of the polyester resin is preferably 40 ° C or higher, more preferably 60 ° C or higher. When the Tg is less than 40 占 폚, there is a case where problems such as easy blocking tend to occur when the coating thickness of the coating layer is increased for the purpose of improving the adhesion.

The acrylic resin is a polymer comprising a polymerizable monomer having a carbon-carbon double bond such as represented by an acrylic or methacrylic monomer. These may be either homopolymers or copolymers. Also included are copolymers of such polymers with other polymers (e.g., polyesters, polyurethanes, etc.). For example, block copolymers and graft copolymers. It also includes a polyester solution, or a polymer (optionally a mixture of polymers) obtained by polymerizing a polymerizable monomer having a carbon-carbon double bond in a polyester dispersion. Similarly, polyurethane solutions, polymers obtained by polymerizing polymerizable monomers having carbon-carbon double bonds in a polyurethane dispersion (mixtures of polymers as the case may be) are also included. Also included are polymers (optionally polymer mixtures) obtained by polymerizing other polymer solutions or polymerizable monomers having carbon-carbon double bonds in the dispersion.

The polymerizable monomer having a carbon-carbon double bond is not particularly limited, but typical compounds include various carboxyl group-containing monomers such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid and citraconic acid, salt; (Meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl Hydroxyl group-containing monomers; Various (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate and lauryl (meth) acrylate; Various vinyl-based monomers such as (meth) acrylamide, diacetone acrylamide, N-methylol acrylamide or (meth) acrylonitrile. Further, the polymerizable monomers as shown below may be used in combination with them. That is, various styrene derivatives such as styrene,? -Methylstyrene, divinylbenzene and vinyltoluene, various vinyl esters such as vinyl acetate and vinyl propionate; various silicon-containing polymerizable monomers such as? -methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, and methacryloyl silicone macromers; Phosphorus-containing vinyl-based monomers; Various halogenated vinyls such as vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, trifluorochloroethylene, tetrafluoroethylene, chlorotrifluoroethylene and hexafluoropropylene; And various conjugated dienes such as butadiene.

The glass transition temperature (hereinafter abbreviated as Tg) of the acrylic resin is preferably 40 占 폚 or higher, more preferably 60 占 폚 or higher. When the Tg is less than 40 占 폚, for the purpose of improving the adhesiveness, when the coating thickness of the coating layer is made thick, there is a case where the problem of easy blocking may occur.

The polyurethane resin in the present invention refers to a polymer compound having a urethane bond in its molecule. Among them, in consideration of suitability for in-line coating, a urethane resin that is water-dispersible or water-soluble is preferable. To impart water-dispersibility or water-solubility, it is possible to introduce a hydrophilic group such as a hydroxyl group, a carboxyl group, a sulfonic acid group, a sulfonyl group, a phosphoric acid group or an ether group into the urethane resin. Of these hydrophilic groups, a carboxylic acid group or a sulfonic acid group is preferably used from the viewpoints of physical properties of the coating film and improvement in adhesion.

As a specific example of the production of the urethane resin, there can be mentioned, for example, a method using a reaction between an isocyanate and a hydroxyl group. As the hydroxyl group to be used as a raw material, a polyol is preferably used, and examples thereof include polyether polyols, polyester polyols, polycarbonate-based polyols, polyolefin polyols and acrylic polyols. These compounds may be used singly or in combination.

Examples of the polyether polyols include polyethylene glycol, polypropylene glycol, polyethylene propylene glycol, polytetramethylene ether glycol, polyhexamethylene ether glycol and the like.

Examples of the polyester polyols include polyhydric alcohols such as polyhydric carboxylic acids (malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, fumaric acid, maleic acid, terephthalic acid, isophthalic acid, (Ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butanediol, 1,3-butanediol, 1,4-butanediol, Propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2- Propanediol, 1,8-octanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexanediol, 2,5- Butanediol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl-1,3-propanediol, Propane diol, cyclohexanediol, bishydroxymethylcyclohexane, dimethanolbenzene, bis Hydroxy include those obtained from ethoxy benzene, alkyl Diallo kanol amine, reaction of the lactone diol, and so on).

Examples of the polycarbonate-based polyols include polycarbonate diols obtained by a deblocking reaction from polyhydric alcohols, dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate and the like, such as poly (1,6-hexylene) carbonate, Poly (3-methyl-1,5-pentylene) carbonate, and the like.

Examples of the polyisocyanate compound used for obtaining the urethane resin include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, methylene diphenyl diisocyanate, phenylene diisocyanate, naphthalene diisocyanate and tolylidine diisocyanate, α, α, , aliphatic diisocyanates having aromatic rings such as? '- tetramethylxylylene diisocyanate, aliphatic diisocyanates such as methylene diisocyanate, propylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate and hexamethylene diisocyanate, cyclohexane Alicyclic diesters such as diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and isopropylidene dicyclohexyl diisocyanate; Such as cyanate and the like. These may be used singly or in combination.

When synthesizing the urethane resin, a conventionally known chain extender may be used. The chain extender is not particularly limited as long as it has two or more active groups reacting with the isocyanate group. The chain extender having a hydroxyl group or a chain extension having two amino groups I can be used universally.

Examples of the chain extender having two hydroxyl groups include aliphatic glycols such as ethylene glycol, propylene glycol and butanediol, aromatic glycols such as xylylene glycol and bishydroxyethoxybenzene, esters such as neopentyl glycol hydroxy pivalate Glycols such as glycols are exemplified. Examples of the chain extender having two amino groups include aromatic diamines such as tolylene diamine, xylylenediamine and diphenylmethane diamine, ethylenediamine, ethylenediamine, propylenediamine, hexanediamine, 2,2- Butyl-2-ethyl-1,5-pentanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,6-hexanediamine, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, dicyclohexylmethanediamine, isopropylidenecyclohexyl-4,4'-diamine, 1,4 - alicyclic diamines such as diaminocyclohexane, 1,3-bisaminomethylcyclohexane, and the like.

The blending ratio of the binder polymer (B) in the coating layer is usually in the range of 10 to 90 wt%, preferably in the range of 20 to 80 wt%. When the content is less than 10% by weight, the adhesion to the release layer may be deteriorated. On the other hand, when the content exceeds 90% by weight, the adhesive performance is saturated and a remarkable effect may not be obtained even if the content is increased by more than 90% by weight. The ratio (weight ratio) of the above-described conductive compound (A) to the binder polymer (B) is usually 90/10 to 1/99, preferably 70/30 to 1/99, 2/98. Outside this range, the antistatic performance or the appearance of the coating film tends to be deteriorated.

As the component (C), at least one compound selected from the group of glycerin (C1), polyglycerin (C2), alkylene oxide adduct of glycerin or polyglycerin (C3) It is preferable to contain a derivative thereof. As the polyglycerin, it is preferable that the average number of glycerin units in the molecule is in the range of 2 to 20. Further, when glycerin is used, the transparency of the obtained coating layer may be slightly lowered.

In addition, the alkylene oxide adduct to glycerin or polyglycerin means that the alkylene oxide adduct has a structure obtained by addition polymerization of an alkylene oxide or a derivative thereof to the hydroxyl group of glycerin or polyglycerin.

Here, the structure of the alkylene oxide or derivative thereof added to the hydroxyl group of the glycerin or polyglycerine skeleton may be different. Further, it may be added to at least one hydroxyl group in the molecule, and it is not necessary that the alkylene oxide or its derivative is added to all the hydroxyl groups.

Preferred as the alkylene oxide or derivative thereof is a structure containing an ethylene oxide or propylene oxide skeleton. If the alkyl chain in the alkylene oxide structure is too long, the hydrophobicity becomes strong, the uniform dispersibility in the coating liquid deteriorates, and the antistatic property and transparency of the coating film tend to deteriorate. Particularly preferred is ethylene oxide.

In the alkylene oxide adduct to glycerin or polyglycerin, the copolymerization ratio of the alkylene oxide or its derivative to the glycerin or polyglycerine skeleton is not particularly limited, but the glycerin or polyglycerin moiety is preferably 1 In one case, the alkylene oxide moiety is preferably 20 or less, more preferably 10 or less. When the ratio of the alkylene oxide or its derivative to the glycerin or polyglycerine skeleton is larger than the above range, the characteristics become close to those obtained when ordinary polyalkylene oxide is used, and when the effect of the present invention is not sufficiently obtained .

The compound (C) in the present invention is particularly preferably a structure in which ethylene oxide or polyethylene oxide is added to diglycerin and the addition number thereof is preferably such that the weight average molecular weight (Mw) of the final alkylene oxide adduct Particularly preferably in the range of 300 to 2,000.

The mixing ratio of the component (C) in the coating layer is usually in the range of 10 to 80% by weight, preferably 20 to 60% by weight. When the content is less than 10% by weight, the effect of improving the coatability is not sufficient. On the other hand, when the content is more than 90% by weight, the effect of improving the coatability is saturated.

The coating liquid used in the present invention may contain a surfactant in order to improve the coating property of the polyester film. As such a surfactant, it is more preferable to use (poly) alkylene oxide, (poly) glycerin or derivatives thereof in the structure, because it does not inhibit the antistatic property of the obtained coating layer.

The coating liquid used in the present invention may contain additives such as defoaming agents, coating improvers, thickeners, organic lubricants, release agents, organic particles, inorganic particles, antioxidants, ultraviolet absorbers, foaming agents, dyes and pigments. These additives may be used singly or in combination of two or more as necessary. As the additives, those containing (poly) alkylene oxide, (poly) glycerin and derivatives thereof in their structure are more preferable because they do not inhibit the antistatic property of the resulting coating layer.

The coating liquid in the present invention is preferably an aqueous solution or an aqueous dispersion in terms of handling, working environment, and stability of the coating liquid composition, but it is a medium mainly composed of water, and if it does not deviate from the gist of the present invention, Or may contain a solvent.

The coating layer in the present invention is preferably provided for applying a coating liquid containing a specific compound to a film, and in particular, in the present invention, it is preferable that the coating is provided by in-line coating which is performed during film formation.

Next, the formation of the release layer in the present invention will be described.

The release layer constituting the first release film and the second release film in the present invention refers to a layer having releasability and specifically refers to a release force F between the acrylic adhesive tape and the release layer in a certain range The present invention can be completed.

The peel force of the first release film 31 with respect to the pressure-sensitive adhesive layer 11 is usually 3 to 50 mN / cm, preferably 5 to 25 mN / cm. If the peeling force of the first release film is less than 3 mN / cm, the release film may easily peel off in a scene where the peeling is not necessarily required. When the peel force of the first release film is more than 50 mN / cm, peeling phenomenon called floating occurs between the second release film and the adhesive layer in the step of peeling off the first release film There is a case.

By suppressing the absolute value of the peeling force of the first release film 31 to be low, even when the absolute value of the peeling force of the second release film 32 is made low, the difference in peeling force between the both release films 31, . In addition, by setting the peeling force of the first release film 31 to a predetermined value or more, it is possible to easily remove the first release film 31 from the pressure-sensitive adhesive layer 11 It is possible to prevent peeling or the phenomenon that the first release film 31 is excited by the adhesive layer 11.

On the other hand, the peeling force of the second release film 32 is usually 20 to 100 mN / cm, preferably 30 to 80 mN / cm. When the peeling force of the second release film is less than 20 mN / cm, there is a case where a part of the second release film peels off when the first release film is peeled. When the peeling force of the second release film is more than 100 mN / cm, there arises a problem that components derived from the pressure-sensitive adhesive layer remain on the second release film.

In the inorganic material double-faced pressure-sensitive adhesive sheet of the present invention, in addition to the peeling force adjustment described above, it is desirable to design the difference in peeling force between the first release film and the second release film.

The peeling force of the second release film 32 is preferably 2.0 times or more, preferably 3.0 times or more, of the peeling force of the first release film 31. [ When the peeling force of the second release film 32 is less than 2.0 times the peeling force of the first release film 31, the second release film 32 is peeled off when the first release film 31 on the light- A phenomenon of lifting from the pressure-sensitive adhesive layer 11 occurs. There may be a problem such that the pressure-sensitive adhesive layer component remains in the second release film 32, or dipping is caused.

The release layer constituting the release film in the present invention can also be provided on the polyester film by the above-described coating stretching method (in-line coating). The coating stretching method (in-line coating) is not limited to the following examples. For example, in sequential biaxial stretching, the coating treatment may be carried out before the first-stage stretching and the second-stage stretching. When the releasing layer is provided on the polyester film by the coating stretching method, the releasing layer can be coated simultaneously with the stretching, and the thickness of the releasing layer can be made thinner depending on the stretching magnification, can do.

The release layer constituting the release film in the present invention preferably contains a curable silicone resin in order to improve releasability. Or a modified silicon type by graft polymerization with an organic resin such as a urethane resin, an epoxy resin, or an alkyd resin may be used as long as the main ingredient of the present invention is not impaired. good.

As the type of the curable silicone resin, any type of curing reaction may be used, such as addition type, condensation type, ultraviolet ray curing type, electron beam curing type, and no-solvent type. Specific examples thereof include KS-774, KS-775, KS-778, KS-779H, KS-847H, KS-856, X-62-2422, X- -62-1387, X-62-5039, X-62-5040, KNS-3051, X-62-1496, KNS320A, KNS316, X-62-1574A / B, X-62-7052, X-62-7028A / B, X-62-7619, X-62-7213, manufactured by Momentive Performance Materials YSR-3022, TPR-6700, TPR-6720, TPR- , XS56-A2982, UV9430, TPR6600, TPR6604, TPR6605, SRX357, SRX211, SD7220, SD7292, LTC750A, LTC760A, LTC303E, SP7259, BY24-468C, SP7248S, BY24-452, DKQ3-202 , DKQ3-203, DKQ3-204, DKQ3-205, DKQ3-210, and the like. In addition, a release control agent may be used in combination to adjust the releasability of the release layer.

In the present invention, the curing conditions for forming the release layer on the polyester film are not particularly limited. When the release layer is provided by off-line coating, the release layer is usually cured at 120 to 200 DEG C for 3 to 40 seconds, Preferably at 100 to 180 DEG C for 3 to 40 seconds as a reference. If necessary, active energy ray irradiation such as heat treatment and ultraviolet ray irradiation may be used in combination. As an energy source for curing by active energy ray irradiation, conventionally known devices and energy sources can be used.

The coated amount of the releasing layer (after drying) is usually in the range of 0.005 to 1 g / m ² , preferably 0.005 to 0.5 g / m ² , more preferably 0.01 to 0.2 g / m ² in terms of coatability. When the amount of coating (after drying) is less than 0.005 g / m ² , stability is lacking in view of coating ability, and it may become difficult to obtain a uniform coating film. On the other hand, when it is applied in a thickness of more than 1 g / m ² , the coating layer adhesion property and curability of the release layer itself may deteriorate.

As the constitution of the inorganic material double-faced pressure-sensitive adhesive sheet in the present invention, it is necessary to adhere a release film to both sides of the pressure-sensitive adhesive layer. Regarding the thickness ratio of each release film, considering the handling property, the thickness of the second release film is usually at least 2 times, preferably at least 3 times, the thickness of the first release film. For example, by thinning the film thickness of the first release film, it is possible to prevent lifting which occurs at the interface between the second release film and the adhesive layer when peeling off the first release film. Further, in the case where the pressure-sensitive adhesive layer is coated on the release surface of the second release film, in consideration of the production cost, in order to eliminate the influences of foreign substances or irregularities in the process, It is preferable to further increase the film thickness of the easy second release film.

In the present invention, conventionally known coating methods such as reverse gravure coating, direct gravure coating, roll coating, die coating, bar coating, and curtain coating can be used as the method of providing the releasing layer to the polyester film. As for the coating method, there is an example described in "Coating method" published in 1979 by the bookstore of the book store "Harasaki".

With respect to the first release film and the second release film in the present invention, the film surface on which the release layer is not provided may be coated with an adhesive layer, an antistatic layer, an oligomer precipitation preventing layer or the like Layer may be provided.

The polyester film constituting the first release film and the second release film may be subjected to a surface treatment such as a corona treatment or a plasma treatment in advance.

In the present invention, in the case of producing a release film, the release layer may be provided on the coating layer after coating the coating layer on the polyester film, once after winding the film, After the layer is applied and dried, the release layer may be provided continuously on the application layer. In the present invention, any technique may be used.

In the release film constituting the inorganic pressure-sensitive adhesive sheet of the present invention, the value of surface specific resistance (R) of the release surface is usually 1 10 ¹⁰ (Ω) or less, preferably 1 10 ⁹ , Preferably 1 x 10 ⁸ (Ω) or less. When R is more than 1 x 10 ¹⁰ (Ω), problems such as the incorporation of foreign matter when the release film is peeled from the inorganic pressure-sensitive adhesive sheet occur.

In the present invention, in at least one of the release films, the amount OL of the oligomer extracted from the surface of the release layer after the heat treatment (180 DEG C, 10 minutes) is preferably 0.5 mg / m ² or less. When the OL is more than 0.5 mg / m ² , when the release surface of the release film is adhered to the pressure-sensitive adhesive layer, oligomers are precipitated with time, and in the inspection step accompanied by optical evaluation, There is a case.

Next, the pressure-sensitive adhesive layer constituting the inorganic material double-sided pressure-sensitive adhesive sheet according to the present invention will be described below. The pressure-sensitive adhesive layer in the present invention means a layer composed of a material having adhesiveness, and conventionally known materials can be used within the range not impairing the knowledge of the present invention. As a concrete example, the case of using an acrylic pressure-sensitive adhesive will be described below.

In the present invention, the acrylic pressure-sensitive adhesive means a pressure-sensitive adhesive layer containing an acrylic polymer as an essential monomer (monomer) component as an acrylic polymer as a base polymer. The acrylic polymer is preferably an acrylic polymer which is formed as an essential monomer component (more preferably, as a main monomer component) with a (meth) acrylic acid alkyl ester having a linear or branched alkyl group and / or an alkoxyalkyl (meth) . The acrylic polymer is preferably an acrylic polymer formed from an alkyl (meth) acrylate and an alkoxyalkyl acrylate having a linear or branched alkyl group as an essential monomer component.

The pressure-sensitive adhesive layer of the present invention is preferably an acrylic pressure-sensitive adhesive layer formed from an alkyl (meth) acrylate having a linear or branched alkyl group and an alkoxyalkyl acrylate as essential monomer components.

The monomer component for forming the acryl-based polymer as the base polymer in the pressure-sensitive adhesive layer of the present invention may further contain a polar group-containing monomer, a polyfunctional monomer or other copolymerizable monomer as a copolymerizable monomer component. The term "(meth) acryl" refers to "acrylic" and / or "methacryl", and the same applies to the other examples. The content of the acryl-based polymer as the base polymer in the pressure-sensitive adhesive layer of the present invention is generally at least 60% by weight, preferably at least 80% by weight based on the total weight (100% by weight) of the pressure-sensitive adhesive layer.

As the monomer component for forming the acrylic polymer, a (meth) acrylic acid alkyl ester having a straight chain or branched chain alkyl group (hereinafter occasionally abbreviated as "(meth) acrylic acid alkyl ester") may preferably be used. Specific examples of the (meth) acrylic acid alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (Meth) acrylate, octyl (meth) acrylate, isobutyl (meth) acrylate, isobutyl (meth) acrylate, (Meth) acrylate, 2-ethylhexyl acrylate, isooctyl (meth) acrylate, nonyl acrylate, nonyl acrylate, isononyl acrylate, decyl (meth) acrylate, isodecyl (Meth) acrylate, octadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl Nonadecyl (meth) acrylate, eicosyl (Meth) acrylic acid alkyl ester having 1 to 20 carbon atoms in the alkyl group and the like. The alkyl (meth) acrylate may be used singly or in combination of two or more. Among them, a (meth) acrylic acid alkyl ester having 2 to 14 carbon atoms in the alkyl group is preferable, and a (meth) acrylic acid alkyl ester having 2 to 10 carbon atoms in the alkyl group is more preferable.

Examples of the polar group-containing monomer include carboxyl group-containing monomers such as (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid and isocrotonic acid, or anhydrides thereof (maleic anhydride); (Meth) acrylate such as 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and 6-hydroxyhexyl Hydroxyl group-containing monomers such as alcohols and allyl alcohol; (Meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl - amide group-containing monomers such as hydroxyethyl acrylamide; Amino group-containing monomers such as aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, and t-butylaminoethyl (meth) acrylate; Glycidyl group-containing monomers such as glycidyl (meth) acrylate and methylglycidyl (meth) acrylate; Cyano group-containing monomers such as acrylonitrile and methacrylonitrile; In addition to N-vinyl-2-pyrrolidone and (meth) acryloylmorpholine, N-vinylpyridines, N-vinylpiperidones, N- vinylpyrimidines, N-vinylpiperazines, N- Vinyl-containing monomers such as vinyl imidazole and N-vinyl oxazole; Sulfonic acid group-containing monomers such as sodium vinylsulfonate; Phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate; Imide group-containing monomers such as cyclohexylmaleimide and isopropylmaleimide; And isocyanate group-containing monomers such as 2-methacryloyloxyethyl isocyanate. These polar group-containing monomers may be used singly or in combination of two or more.

Examples of the polyfunctional monomer include hexanediol di (meth) acrylate, butanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (Meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, Acrylate, tetramethylolmethane tri (meth) acrylate, allyl (meth) acrylate, vinyl (meth) acrylate, divinylbenzene, epoxy acrylate, polyester acrylate and urethane acrylate. The polyfunctional monomers may be used alone or in combination of two or more.

The content of the polyfunctional monomer is preferably 0.5% by weight or less based on 100% by weight of the monomer component forming the acrylic polymer. If the content exceeds 0.5% by weight, for example, the cohesive force of the pressure-sensitive adhesive layer becomes too high, and the stress relaxation property may be lowered.

Examples of the copolymerizable monomers other than the polar group-containing monomers and the polyfunctional monomers (other copolymerizable monomers) include cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, isobonyl (Meth) acrylic acid ester such as (meta) acrylic acid ester having an alicyclic hydrocarbon group and (meth) acrylic acid ester having an aromatic hydrocarbon group such as phenyl (meth) acrylate, (Meth) acrylic acid esters other than monomers and polyfunctional monomers; Vinyl esters such as vinyl acetate and vinyl propionate; Aromatic vinyl compounds such as styrene and vinyl toluene; Olefins or dienes such as ethylene, butadiene, isoprene and isobutylene; Vinyl ethers such as vinyl alkyl ether; Vinyl chloride, and the like.

The acryl-based polymer can be produced by polymerizing the above-mentioned monomer components by a conventionally known or conventional polymerization method. Examples of the polymerization method of the acrylic polymer include a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, and a polymerization method by active energy ray irradiation (active energy ray polymerization method). Of these, a solution polymerization method and an active energy ray polymerization method are preferable in terms of transparency, water resistance, and manufacturing cost.

Examples of the active energy ray to be irradiated in the above active energy ray polymerization (photopolymerization) include ionizing radiation such as? Rays,? Rays,? Rays, neutron rays, and electron beams, and ultraviolet rays. Particularly, Are preferable for the use of the present invention. The irradiation energy of the active energy ray, the irradiation time, the irradiation method and the like are not particularly limited as long as the present invention is not damaged.

In the solution polymerization, various general solvents can be used. As specific examples, esters such as ethyl acetate and n-butyl acetate; Aromatic hydrocarbons such as toluene and benzene; aliphatic hydrocarbons such as n-hexane and n-heptane; Alicyclic hydrocarbons such as cyclohexane and methylcyclohexane; And organic solvents such as ketones such as methyl ethyl ketone and methyl isobutyl ketone. The solvent may be used alone or in combination of two or more.

Upon preparation of the acrylic polymer, a polymerization initiator such as a thermal polymerization initiator or a photopolymerization initiator (photoinitiator) may be used depending on the kind of the polymerization reaction. The polymerization initiator may be used alone or in combination of two or more.

The photopolymerization initiator is not particularly limited, and examples thereof include a benzoin ether photopolymerization initiator, an acetophenone photopolymerization initiator, an? -Ketol photopolymerization initiator, an aromatic sulfonylchloride photopolymerization initiator, a photoactive oxime photopolymerization initiator, A benzene-based photopolymerization initiator, a benzophenone-based photopolymerization initiator, a ketal-based photopolymerization initiator, a thioxanthone-based photopolymerization initiator, and the like. The amount of the photopolymerization initiator to be used is not particularly limited as long as it does not impair the knowledge of the present invention. For example, it is preferably in the range of 0.01 to 0.2 parts by weight based on 100 parts by weight of the monomer component forming the acrylic polymer.

Specific examples of the benzoin ether photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2,2-dimethoxy-1,2 -Diphenylethane-1-one, anisole methyl ether, and the like. Examples of the acetophenone photopolymerization initiator include 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexylphenylketone, 4-phenoxydichloroacetophenone, 4- (t-butyl) dichloroacetophenone, and the like. Examples of the? -ketol-based photopolymerization initiator include 2-methyl-2-hydroxypropiophenone and 1-4- (2-hydroxyethyl) phenyl] -2-methylpropan-1-one. Specific examples of the aromatic sulfonyl chloride-based photopolymerization initiator include 2-naphthalenesulfonyl chloride and the like. Examples of the photoactive oxime-based photopolymerization initiator include 1-phenyl-1,1-propanedione-2- (o-ethoxycarbonyl) -oxime and the like. Examples of the benzoin-based photopolymerization initiator include benzoin and the like. The benzyl-based photopolymerization initiator includes, for example, benzyl and the like. Specific examples of the benzophenone-based photopolymerization initiator include benzophenone, benzoylbenzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, polyvinylbenzophenone, and? -Hydroxycyclohexylphenylketone. Specific examples of the ketal-based photopolymerization initiator include benzyldimethyl ketal and the like. Specific examples of the thioxanthone photopolymerization initiator include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4- Propyl thioxanthone, dodecylthioxanthone, and the like.

Specific examples of the thermal polymerization initiator include azo polymerization initiators such as 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, 2,2'-azobis (2-methylpropionic acid) dimethyl, 4,4'-azobis-4-cyanovaleric acid, azobisisobalonitrile, 2,2'-azobis (2-amidinopropane) dihydrochloride, Azo bis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis (2-methylpropionamidine) Based polymerization initiator (e.g., dibenzoyl peroxide, tert-butyl fumarate, etc.), a redox-based polymerization initiator, and the like . The amount of the thermal polymerization initiator to be used is not particularly limited as long as it does not impair the present invention.

A cross-linking agent, a cross-linking accelerator, a tackifier (for example, a rhodine derivative resin, a polyterpene resin, a petroleum resin, an oil-soluble phenol resin or the like), and a tackifier may be added to the acrylic pressure-sensitive adhesive layer used as one form of the pressure- Known additives such as antioxidants, fillers, coloring agents (pigments or dyes), ultraviolet absorbers, antioxidants, chain transfer agents, plasticizers, softeners, surfactants and antistatic agents may be used within a range that does not impair the properties of the present invention have. Further, when forming the pressure-sensitive adhesive layer, various general solvents can be used. The type of the solvent is not particularly limited, and those exemplified as the solvents used in the solution polymerization described above may be used.

The cross-linking agent can control the gel fraction of the pressure-sensitive adhesive layer by crosslinking the base polymer of the pressure-sensitive adhesive layer. Examples of the crosslinking agent include urea crosslinking agents, epoxy crosslinking agents, melamine crosslinking agents and peroxide crosslinking agents, urea crosslinking agents, metal alkoxide crosslinking agents, metal chelating crosslinking agents, metal salt crosslinking agents, carbodiimide crosslinking agents, oxazoline crosslinking agents, Based cross-linking agent, an amine-based cross-linking agent and the like, and isocyanate-based cross-linking agents and epoxy-based cross-linking agents can be suitably used. The crosslinking agent may be used alone or in combination of two or more.

Next, in the inorganic material double-sided pressure-sensitive adhesive sheet of the present invention, when an acrylic pressure-sensitive adhesive composition is used in forming the pressure-sensitive adhesive layer, which is a constituent unit thereof, The display surface of the liquid crystal display panel is replaced with a transparent pressure sensitive adhesive sheet having a refractive index close to that of the optical member so as to improve the light transmittance and suppress the lowering of the brightness and contrast of the image display apparatus It is desirable to design the pressure-sensitive adhesive layer itself in a flexible manner. For example, the storage elastic modulus G 'in dynamic viscoelasticity is preferably 1.0 10 ⁵ Pa or less, more preferably 5.0 10 ⁴ Pa or less. When the storage elastic modulus (G ') exceeds 1.0 10 ⁵ Pa, for example, when the gap existing between the optical members is high, the packed pressure-sensitive adhesive layer does not reach the corner and is peeled off at the end, And the like.

The thickness of the pressure-sensitive adhesive layer constituting the inorganic material double-sided pressure-sensitive adhesive sheet according to the present invention is usually 25 to 200 占 퐉, preferably 50 to 100 占 퐉. When the thickness is less than 25 占 퐉, for example, the gap formed between the optical members becomes too large, and it may be difficult to fill the pressure sensitive adhesive layer to the corner. On the other hand, when the thickness of the pressure-sensitive adhesive layer is more than 200 占 퐉, the thickness of the pressure-sensitive adhesive layer becomes excessively thicker than the gap formed between the optical members, thereby causing a problem such as an excessive amount of the pressure- .

Example

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples unless it departs from the gist thereof. The measurement method used in the present invention is as follows.

(1) Measurement of Intrinsic Viscosity of Polyester:

1 g of a polyester obtained by removing the pigment and other polymer components which are incompatible with the polyester were dissolved and dissolved in 100 ml of a mixed solvent of phenol / tetrachloroethane = 50/50 (weight ratio) and measured at 30 캜.

(2) Measurement of average particle diameter (d ₅₀ : 탆)

The value obtained by integration (weight basis) of 50% in the equivalent-type distribution measured using a centrifugal sedimentation type particle size distribution measuring apparatus (SA-CP3 type manufactured by Samazu Corporation) was defined as an average particle diameter.

(3) Measurement of glass transition temperature (Tg) of polyester resin:

Using a DS C-II type measuring device manufactured by Perkin Elmer, the temperature of the sample was raised to 10 mg / min under a nitrogen gas stream at a heating rate of 10 占 폚 / min, and the baseline start temperature was defined as Tg.

(4) Measurement of peel force (F1 · F2) of release film:

The one side of the bottom side adhesive tape ("No.502" manufactured by Kyodo Kogyo Co., Ltd.) was adhered to the surface of the release layer of the sample film, cut into a size of 50 mm x 300 mm, and left at room temperature for 1 hour. The peel strength was measured by using a tensile tester (" Intesco Model 2001 type " manufactured by Tesco Co., Ltd.) and subjected to 180 ° peeling under a condition of a tensile rate of 300 mm / min.

(5) Measurement of the surface resistivity (R) of the release film:

The surface resistivity was measured on the surface of the release layer of the sample film in accordance with the following method (5-1). (5-1), since the surface resistivity higher than 1 x 10 ⁸ ? Can not be measured, the method of (5-2) was used for the sample which could not be measured by (5-1) .

<Measurement method>

(5-1) Low resistivity meter manufactured by Mitsubishi Chemical Co., Ltd.: Loresta GP MCP-T600 was used and the surface resistivity of the sample was measured after humidity was maintained for 30 minutes in a measuring atmosphere at 23 캜 and 50% RH.

(5-2) High Resistance Measuring Instrument manufactured by Hewlett-Packard Company, Japan: HP4339B and Measuring Electrode: HP16008B was used and the sample was conditioned for 30 minutes in a measuring atmosphere at 23 占 폚 and 50% RH, and the surface resistivity was measured.

<Criteria>

A ... R (Ω) is 1 × 10 ⁸ or less (practical level, particularly good).

B ... R (Ω) is 1 × 10 ⁹ or less (practical level).

C ... R (Ω) is less than or equal to 1 × 10 ¹⁰ (practically, level at which it may be a problem).

D ... R (Ω) exceeds 1 × 10 ¹⁰ (practically difficult level).

(6) Measurement of oligomer amount (OL) extracted from the surface of the release layer of the release film:

The release film that has not been heat-treated in advance is heated in air at 180 캜 for 10 minutes. Thereafter, the film subjected to the heat treatment is brought into close contact with the inner surface of a box having a height of 10 cm and a height of 3 cm, which is opened at the top, as much as possible to form a box-like shape. Then, 4 ml of DMF (dimethylformamide) was added to the box prepared as described above, and the mixture was allowed to stand for 3 minutes, and DMF was recovered. The recovered DMF performance liquid chromatography (manufactured by Shimadzu Corporation prepared: LC-7A) is supplied to, obtain the oligomer content in the DMF, the value, divided by the film area in contact the DMF, the film surface Oligomer amount (mg / m ²⁾ .

The amount of oligomer in DMF was determined from the peak area ratio of the standard sample peak area and the measured sample peak area (absolute calibration curve method). A standard sample was prepared by precisely weighing oligomers (cyclic trimer) prepared in advance and dissolving in precisely weighed DMF. The concentration of the standard sample is preferably in the range of 0.001 to 0.01 mg / ml.

Conditions for liquid chromatography were as follows.

Mobile phase A: acetonitrile

Mobile phase B: 2% aqueous acetic acid solution

Column: &quot; MCI GEL ODS 1HU &quot; manufactured by Mitsubishi Kagaku Co.,

Column temperature: 40 ° C

Flow rate: 1 ml / min

Detection wavelength: 254 nm

(7) Evaluation of coating film adhesion of release film (substitution of practical properties):

The sample film was allowed to stand in an ambient temperature and humidity bath at 60 DEG C and 80% RH for 4 weeks, and then the sample film was taken out. Thereafter, the releasing surface of the sample film was rubbed five times by hand contact, and the degree of the releasing of the releasing layer was judged by the following criteria.

<Criteria>

A ... No dropping of the coating film is seen (practical level).

B ... The coating becomes white but does not fall off (practical level).

C ... The removal of the coating film was confirmed (difficult level for practical use).

(8) Measurement of storage elastic modulus (G ') of the pressure-sensitive adhesive layer:

The separator was peeled off from the base-side pressure-sensitive adhesive sheet obtained in Examples and Comparative Examples, and only the acrylic pressure-sensitive adhesive layer was laminated to obtain a laminate of an acrylic pressure-sensitive adhesive layer having a thickness (after drying) of 1.5 mm +/- 0.1 mm. The measurement sample was measured at a heating rate of 5 DEG C / minute in a range of -70 to 200 DEG C under the condition of a frequency of 1 Hz by using "Advanced Rheometric Expansion System (ARES)" manufactured by Rheometric Scientific Co., (G &apos;). The storage elastic modulus (G ') of the pressure-sensitive adhesive layer used in Examples and Comparative Examples of the present invention was 5.0 x 10 &lt; ⁴ &gt;

(9) Appearance Appearance (substitution of practical properties):

A sample film having a width of 1000 mm was irradiated with halogen light to the surface of the release layer provided with the coating layer for about 10 m in the longitudinal direction and the appearance of the release layer as a visual indicator was judged to judge appearance appearing as a mura Were judged by the standards.

<Criteria>

A: The shape that looks like a stain is not confirmed and is good.

B: It looks a bit like a stain.

C: The shape that looks like a stain is confirmed, which is not good.

In the above example, although a speckle is confirmed with respect to a long sample, it is possible to determine whether or not speckle is present in the same manner as described above, even if the film has a size of about A4 size.

(10) Deep fingering evaluation (substitution of practical characteristics):

The following pressure-sensitive adhesive composition was applied to the second release film and heat-treated at 100 캜 for 5 minutes to obtain an adhesive layer having a thickness (after drying) of 150 탆. Next, in the inorganic material double-sided pressure-sensitive adhesive sheet in which the first release film was adhered to the surface of the pressure-sensitive adhesive layer, the peeling state was observed at the time of peeling off the first release film, and the occurrence situation of dipping was judged by the following criteria.

&Lt; Acrylic pressure-sensitive adhesive composition &

(Monomer formulation composition)

70% by weight of 2-ethylhexyl acrylate

2-methoxyethyl acrylate 29 weight%

4-hydroxybutyl acrylate 1 wt%

To 100 parts by weight of the above monomer composition, 0.1 part of Coronate L manufactured by Nihon Polyurethane Co., Ltd. was added to obtain a composition for forming an acrylic pressure-sensitive adhesive layer.

<Criteria>

A: Very smoothly peeled off, no peeling stripe (streak), no peeling sound.

B: A slight peeling stripe is observed, a slight peeling sound is generated, or a slight dipping occurs (practically, a level at which a problem may occur).

C: Peeling stripes are observed, and a peeling sound is generated. Dipping occurs (practically, the problem level).

(11) Evaluation of peelability of first and second release films (substitution of practical properties):

In item (10), sensory evaluation was performed on the situation of the interface between the second release layer and the pressure-sensitive adhesive layer at the time of peeling off the first release film by the following criteria.

<Criteria>

A: No abnormality is observed at the interface between the second release layer and the pressure-sensitive adhesive layer (practically, problem-free level).

B: At the interface between the second release layer and the pressure-sensitive adhesive layer, slight lift-off is observed (a level at which practical problems may occur).

C: Clear lifting is observed at the interface between the second release layer and the pressure-sensitive adhesive layer (practically, problematic level).

(12) Evaluation of antistatic property of double-faced adhesive sheet for inorganic material (substitution of practical properties):

Under the low humidity atmosphere (30% RH ± 5% RH), the first release film and the second release film were peeled off in this order, and the occurrence of peeling electrification was judged based on the following criteria.

<Criteria>

A: Even when a release film is peeled off, no peeling electrification occurs at all, and it is a particularly good level (practically, problem-free level).

B: Peeling electrification does not occur or slight peeling electrification occurs even when a releasing film is peeled off (practically no problem level).

C: At the time of peeling off a release film, a slight peeling electrification may be confirmed (a level at which there is a problem in practical use).

D: At the time of peeling off a release film, slight peeling electrification is confirmed (practically, problematic level).

(13) Evaluation of oligomer blocking property of an inorganic material double-faced adhesive sheet (substitution of practical properties):

After the pressure-sensitive adhesive was applied and dried, both sides of the release layer and the pressure-sensitive adhesive layer on the side to which the pressure-sensitive adhesive was applied were observed using an optical microscope, and the presence or absence of oligomer was observed.

<Criteria>

A: Even when a release agent was applied and dried using a release film, generation of oligomer was not confirmed (practically no problem level).

B: When a pressure-sensitive adhesive is applied and dried using one of the release films, the generation of oligomers is confirmed (a level at which practical problems may occur).

C: Even when a release agent was applied and dried using a release film, generation of oligomer was confirmed (practically, problematic level).

(14) Overall evaluation (substitution of practical characteristics):

With respect to various evaluation items of the dipping occurrence situation, releasability, antistatic property, oligomer blocking property, adhesion property and coated appearance, using the inorganic material double-faced pressure-sensitive adhesive sheet produced in the examples and the comparative examples, A comprehensive evaluation was conducted.

However, regarding the evaluation of the antistatic property in which the four-step evaluation is performed, the following determination criteria are applied while considering "A" as "A", "C" as "B" and "D" as "C" .

<Criteria>

A: Peeling property, antistatic property, oligomer blocking property, dip tipping property, adhesion property, and coated appearance are both "A" (practically no problem level).

B: At least one of peelability, antistatic property, oligomer blocking property, dip property, adhesion property, and coated appearance is &quot; B &quot;

C: At least one of peeling property, antistatic property, oligomer blocking property, dipping property, adhesion property, and coated appearance is "C" (practical problematic level).

The polyester used in Examples and Comparative Examples was prepared as follows.

&Lt; Production of polyester &

Production Example 1 (polyethylene terephthalate A1)

100 parts of dimethyl terephthalate, 60 parts of ethylene glycol, and 0.09 parts of magnesium acetate-4 hydrate were placed in a reactor, and the temperature was elevated by heating. Methanol was distilled off to carry out transesterification reaction. The temperature was elevated to substantially complete the transesterification reaction. Subsequently, 0.04 part of ethyl acetate phosphate and 0.03 part of antimony trioxide were added to the ethylene glycol slurry, and then the temperature was allowed to reach 280 占 폚 and the pressure to 15 mmHg in 100 minutes, and gradually the pressure was gradually reduced to 0.3 mmHg in 100 minutes. After 4 hours, the system was returned to atmospheric pressure to obtain polyethylene terephthalate A1 having an intrinsic viscosity of 0.61.

Production Example 2 (polyethylene terephthalate A2)

Polyethylene terephthalate A2 having an intrinsic viscosity of 0.62 was obtained in the same manner as in Preparation Example 1 except that 0.6 parts of silica particles having an average particle diameter of 2.5 占 퐉 was added in Production Example 1. [

Production Example 3 (Production of polyester film F1)

Polyethylene terephthalate A1 and A2 were blended at a ratio of 80% and 20%, respectively, as a surface layer raw material and a polyethylene terephthalate A1 = 100% raw material as an intermediate layer raw material, and the resulting mixture was fed to two vented extruders, Extruded at 290 占 폚 and then cooled and solidified on a cooling roll having a surface temperature set at 40 占 폚 by electrostatic adhesion to obtain an amorphous film having a thickness of about 1300 占 퐉.

Was applied to this film at 85 ℃ to 3.5 times longer, and to the application amount of the coating layers of the compositions shown in Table 1 consisting of the components (after drying) is 0.03 g / m ² in the longitudinal direction, the transverse direction at 100 ℃ To obtain a polyester film F1 provided with a coating layer having a thickness of 100 mu m (thickness composition ratio = 2.5 mu m / 95 mu m / 2.5 mu m).

&Lt; Composition of coating agent &

(A): a mixture of polyethylene dioxythiophene and polystyrene sulfonic acid, manufactured by Baytron PAG

(B1): polyurethane resin

664 parts of terephthalic acid, 631 parts of isophthalic acid, 472 parts of 1,4-butanediol, and 447 parts of neopentyl glycol. Subsequently, 321 parts of adipic acid and 268 parts of dimethylolpropionic acid were added to the obtained polyester polyol to obtain a polyester polyol A containing pendant carboxyl group. Further, 160 parts of hexamethylene diisocyanate was added to 1880 parts of the polyester polyol A to obtain a polyurethane resin water-based paint.

(B2): polyester resin Tg = 63 DEG C

Acid component: terephthalic acid 50 mol%

        48 mol% of isophthalic acid

        2-mol% of 5-Na sulfoisophthalic acid

Diol component: Ethylene glycol 50 mol%

  Neopentyl glycol 50 mol%

(B3): Acrylic resin (RX-7023ED, manufactured by Nippon Carbide Co., Ltd.)

(C1): glycerin having n = 1 in the above formula (3)

(C2): polyglycerin having n = 2 in the formula (3)

(C3): Polyglycerin having n = 10 in the formula (3)

(C4): Polyethylene oxide adduct to polyglycerine skeleton of formula (3) wherein n = 2. Average molecular weight 350

(C5): a polyethylene oxide adduct of a polyglycerine skeleton having n = 2 in the above formula (3). Average molecular weight 2000

(C6): a polypropylene oxide adduct of a polyglycerine skeleton having n = 2 in the formula (3). Average molecular weight 750

Production Example 4 (Production of polyester film F2) - Production Example 16 (Production of polyester film F14)

Production Example 3 was carried out in the same manner as in Production Example 3 except that the composition of the coating layer was changed as shown in Table 1. Each polyester film was obtained.

Production Example 17 (Production of polyester film F15)

A polyester film F15 was produced in the same manner as in Production Example 3, except that the film thickness constitution in Production Example 3 was different (thickness composition ratio = 2.5 占 퐉 / 70 占 퐉 / 2.5 占 퐉).

Production Example 18 (Production of polyester film F16)

A polyester film F16 was produced in the same manner as in Production Example 3, except that the film thickness configuration was changed to (thickness ratio = 2.5 占 퐉 / 45 占 퐉 / 2.5 占 퐉) in Production Example 3.

Production Example 19 (Production of polyester film F17)

A polyester film F17 was produced in the same manner as in Production Example 17, except that a coating layer was not provided in Production Example 17.

The composition of the release layer used in Examples and Comparative Examples is as follows.

(Release Layer Composition-A)

Curable silicone resin

(LTC303E: manufactured by Toray Dow Corning) 100 parts

Curing agent (SRX212: manufactured by Toray Dow Corning) 1 part

MEK / toluene mixed solvent (mixing ratio is 1: 1) 1500 parts

(Release Layer Composition-B)

Curing type silicone resin (KS-847H: Shin-Etsu Chemical Co., Ltd.) 100 parts

Curing agent (PL-50T: manufactured by Shin-Etsu Chemical Co., Ltd.) 1 part

MEK / toluene mixed solvent (mixing ratio is 1: 1) 1500 parts

(Release Layer Composition - C)

Curable silicone resin (KS-847H: Shin-Etsu Chemical Co., Ltd.) 95 parts

Heavy duty control system (BY24-4980: manufactured by Toray Dow Corning) 5 pcs.

Curing agent (PL-50T: manufactured by Shin-Etsu Chemical Co., Ltd.) 1 part

MEK / toluene mixed solvent (mixing ratio is 1: 1) 1500 parts

Example 1:

&Lt; Preparation of first release film &

The release layer composition of -A on the coating layer of the polyester film having a thickness of F15 50㎛ application amount (after drying) is such that 0.1 g / m ^2, was coated by an offline, a reverse gravure coating method, 120 ℃, Followed by heat treatment for 30 seconds.

From the above, the characteristics of the obtained first release film are shown in Tables 2 and 3. In Table 2, the number of the embodiment means the number of the embodiment in Table 3 (hereinafter the same).

&Lt; Preparation of second release film &

In the off-line so that the method, the coating amount is 0.1g / m ² (after drying) of the release layer composition -C on the coating layer of the polyester film in 100㎛ F1 thick, was applied by a reverse gravure coating method, 120 ℃ , And heat-treated for 30 seconds. The properties of the obtained second release film and the inorganic material double-faced adhesive sheet are shown in Tables 2 and 3.

&Lt; Preparation of inorganic double-faced pressure-sensitive adhesive sheet &

A coating liquid composed of the following acrylic pressure-sensitive adhesive composition was coated on the releasing layer of the obtained second release film and heat-treated at 100 캜 for 5 minutes to obtain a pressure-sensitive adhesive layer having a coating thickness (after drying) of 50 탆.

&Lt; Composition for forming an acrylic pressure-sensitive adhesive layer &

(Monomer formulation composition)

70% by weight of 2-ethylhexyl acrylate

2-methoxyethyl acrylate 29 weight%

4-hydroxybutyl acrylate 1 wt%

To 100 parts by weight of the above monomer composition, 0.1 part of Coronate L manufactured by Nihon Polyurethane Co., Ltd. was added to obtain a composition for forming an acrylic pressure-sensitive adhesive layer.

Subsequently, the releasing layer of the first release film and the pressure-sensitive adhesive layer were adhered to each other under a room temperature (23 ° C ± 3 ° C) atmosphere to obtain an inorganic material double-sided pressure-sensitive adhesive sheet.

Examples 2 to 17 and Comparative Examples 1 to 2:

The procedure of Example 1 was repeated except that the coating composition, the release layer composition, and the thickness of the polyester film substrate were changed as shown in Tables 1 and 2, and the first release film and the second release film A film was obtained. Thereafter, both were adhered through the pressure-sensitive adhesive layer to obtain an inorganic material double-sided pressure-sensitive adhesive sheet. Table 2 and Table 3 show the properties of each release film and inorganic material double-faced adhesive sheet obtained in the above Examples and Comparative Examples.

[Table 1]

[Table 2]

[Table 3]

Industrial availability

The inorganic material double-faced pressure-sensitive adhesive sheet of the present invention is suitable as various optical members such as antistatic property, releasability, oligomer blocking property and coated outer appearance, for example, a member for manufacturing a liquid crystal polarizing plate and a member for manufacturing a capacitive touch panel .

10: Double-sided pressure sensitive adhesive sheet
11: Pressure-sensitive adhesive layer
13: First release film substrate
14: First coating layer
15: First release agent layer
23: Second release film substrate
24: second coating layer
25: Second release agent layer
31: First release film (light release sheet)
32: Second release film (heavy-weight recycled sheet)

Claims (8)

Sensitive adhesive sheet in which a release film having different peel strengths is laminated on both sides of a pressure-sensitive adhesive layer, wherein the first release film is smaller than the second release film with respect to the peeling force, and at least one release film is a polyester film (A) and a binder polymer (B), wherein the blend ratio of the binder polymer (B) is in the range of 40 to 90 wt%, and the binder polymer (B) (180 DEG C, 10 minutes) in at least one release film, and the amount OL of the oligomer extracted from the surface of the release layer is 0.5 mg / m &lt; ² &gt;.&lt; / RTI &gt; delete The inorganic material double-sided pressure-sensitive adhesive sheet according to claim 1, wherein the conductive compound (A) is a polymer obtained by singly or copolymerizing a thiophene or thiophene derivative. The inorganic material double-sided pressure-sensitive adhesive sheet according to claim 3, wherein the polymer of the thiophene or thiophene derivative is a polymer obtained by polymerizing the compound of the following formula (1) or (2) in the presence of a polyanion.

In the formula (1), R ¹ and R ² each independently represent a hydrogen atom, an aliphatic hydrocarbon group of 1 to 12 carbon atoms, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group, and examples thereof include a methyl group, Propyl group, butyl group, cyclohexylene group, benzene group and the like. In the above formula (2), n is an integer of 1 to 4. The inorganic material double-sided pressure-sensitive adhesive sheet according to claim 4, wherein the polyanion is at least one selected from the group consisting of poly (meth) acrylic acid, polymaleic acid and polystyrenesulfonic acid. The positive photosensitive resin composition according to claim 1, wherein the coating layer comprises at least one compound (C) selected from the group of glycerin (C1), polyglycerin (C2), alkylene oxide adduct of glycerin or polyglycerin Or a derivative thereof, and the blending ratio thereof is 10 to 40% by weight. delete delete

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