KR20190071604A - Pressure-sensitive adhesive, pressure sensitive adhesive sheet and laminate - Google Patents

Abstract

The present invention relates to an adhesive which can form an adhesive layer having good yield and hardly deteriorating releasability after time is passed at the high temperature, to an adhesive sheet, and to a laminate. The adhesive comprises: a urethane polyol (A) having a weight average molecular weight of 100,000 to 500,000, which is a reaction product of polyol (a) and polyisocyanate (b); an isocyanate curing agent (B); an antioxidant (D); an antistatic agent (E); and polyfunctional polyol (F), wherein the polyfunctional polyol (F) has 3 or more hydroxyl groups in one molecule.

Description

[0001] PRESSURE-SENSITIVE ADHESIVE, PRESSURE SENSITIVE ADHESIVE SHEET AND LAMINATE [0002]

The present invention relates to a pressure-sensitive adhesive having antistatic properties. The present invention also relates to a pressure-sensitive adhesive sheet and a laminate using the pressure-sensitive adhesive.

A display device such as a flat panel display (FPD) such as a liquid crystal display (LCD) or an organic electroluminescence display (OLED), a touch panel display (TSP) , Portable information terminals, and the like.

BACKGROUND ART [0002] Surface protecting sheets have heretofore been widely used to protect an optical member used in a display device from scratches, dust, and the like.

As the adhesive layer of the surface protective sheet, a pressure-sensitive adhesive containing a urethane resin (hereinafter referred to as urethane pressure-sensitive adhesive) has been used because of its excellent adhesive strength and abrasion resistance to various adherends typified by glass. Such a surface protective sheet may require antistatic performance in order to prevent destruction of electronic devices inside the FPD or TSP due to static electricity generated when the surface protection sheet is detached from the adherend.

Patent Document 1 discloses a polyurethane resin composition containing a polyurethane resin (A) containing a hydroxyl group, a polyfunctional isocyanate compound (B), a compound (C) having a molecular weight of 250 to 1000 and containing no hydroxyl group and isocyanate group, (D) is contained in an amount of 0.05 to 5 parts by weight based on 100 parts by weight of the total of the components (A) to (C).

Patent Document 2 discloses a urethane pressure-sensitive adhesive containing a polyurethane resin, wherein the polyurethane resin is a polyurethane resin obtained by curing a composition containing a polyol (A) and a polyfunctional isocyanate compound (B) And the polyfunctional isocyanate compound (B) have an equivalent ratio of an NCO group and an OH group of more than 1.0 and not more than 5.0 as an NCO group / OH group, and the urethane pressure sensitive adhesive is an ionic liquid containing a fluoro organic anion Based pressure-sensitive adhesives.

Japanese Patent Application Laid-Open No. 2017-105866 Japanese Patent Application Laid-Open No. 2015-098503

However, conventional antistatic agents contain an antistatic agent to obtain desired antistatic properties. However, since the metal catalyst in the pressure-sensitive adhesive agent is coordinated with the antistatic agent to lower the reaction rate of the isocyanate curing agent, the curing rate is lowered. When the surface protective sheet is manufactured by roll-to-roll rather than sheet-fed, the step generated when the head of the surface protective sheet is stuck to the roll of the coating machine Is added to the pressure-sensitive adhesive layer by pressure and is wound, the influence of the above-mentioned step is left as an indentation on the pressure-sensitive adhesive layer. Therefore, it is necessary to dispose the surface protecting sheet until the indentation disappears. A decrease in the curing rate due to the incorporation of the antistatic agent lowers the cohesive force of the pressure-sensitive adhesive layer immediately after the coating, so that the sheet length until the indentation disappears increases and the yield of the surface protective sheet deteriorates there was. In addition, the lowering of the curing rate causes a decrease in the crosslinking density of the pressure-sensitive adhesive layer, resulting in an increase in the adhesive force after a lapse of a high temperature and deteriorating re-peeling property. Further, since the pressure-sensitive adhesive of Patent Document 2 is produced by the so-called one-shot method without using a urethane polyol, the cohesive force of the pressure-sensitive adhesive layer immediately after coating is low and the yield is poor.

An object of the present invention is to provide a pressure-sensitive adhesive, a pressure-sensitive adhesive sheet and a laminate capable of forming a pressure-sensitive adhesive layer which is good in yield and hardly deteriorates in releasability after a lapse of a high temperature.

Means for Solving the Problems As a result of intensive investigations to solve the above problems, the present inventors have found out that the above-described problems can be solved by the following modes, and have completed the present invention.

(A), an isocyanate curing agent (B), an antioxidant (D), an antistatic agent (E) and an antioxidant (E) having a weight average molecular weight of 100,000 to 500,000, which are reactants of the polyol (a) and the polyisocyanate A pressure-sensitive adhesive comprising a polyfunctional polyol (F).

[2] The pressure-sensitive adhesive according to [1], wherein the polyfunctional polyol (F) has 3 or more hydroxyl groups in one molecule.

[3] A pressure-sensitive adhesive according to [1] or [2], further comprising a plasticizer (C).

[4] The pressure-sensitive adhesive according to [3], wherein the plasticizer (C) is contained in an amount of 0.1 to 100 parts by mass based on 100 parts by mass of the urethane polyol (A).

[5] A pressure-sensitive adhesive according to any one of [1] to [4], wherein the polyfunctional polyol (F) is contained in an amount of 2 to 50 parts by mass per 100 parts by mass of the urethane polyol (A).

[6] The pressure-sensitive adhesive according to any one of [1] to [5], wherein the polyfunctional polyol (F) has a primary hydroxyl group at the terminal.

[7] A pressure-sensitive adhesive sheet comprising a substrate and a pressure-sensitive adhesive layer which is a cured product of the pressure-sensitive adhesive according to any one of [1] to [6].

[8] A laminate comprising a member selected from the group consisting of a transparent conductive film, a glass, an acrylic plate, a polycarbonate plate, an olefin plate, and an inorganic barrier layer, and the adhesive sheet described in [7].

According to the present invention described above, it is possible to provide a pressure-sensitive adhesive, a pressure-sensitive adhesive sheet and a laminate which can form a pressure-sensitive adhesive layer which is good in yield and hardly deteriorates in releasability after a lapse of a high temperature time.

Terms are defined before the description of the present invention. In the present specification, an adherend refers to a relative to which an adhesive tape is applied. The adhesive sheet includes a substrate and a pressure-sensitive adhesive layer composed of a cured product of the pressure-sensitive adhesive of the present specification. "Tape", "film", and "sheet" have the same meaning. The main component means the component having the highest compounding amount among the components to be compounded in plural.

In this specification, " molecular weight " means a number average molecular weight (Mn) unless otherwise specified. "Mn" is the number average molecular weight in terms of polystyrene determined by gel permeation chromatographic (GPC) measurement.

The pressure-sensitive adhesive of the present embodiment is a pressure-sensitive adhesive containing urethane polyol (A), isocyanate curing agent (B), antioxidant (D) and antistatic agent (A) having a weight average molecular weight of 100,000 to 500,000 as a reaction product of polyol (a) and polyisocyanate E) and a polyfunctional polyol (F).

The pressure-sensitive adhesive of the present embodiment is preferably used as a pressure-sensitive adhesive sheet by forming a pressure-sensitive adhesive layer by coating. The pressure-sensitive adhesive sheet preferably includes a base material.

The pressure-sensitive adhesive of the present embodiment can eliminate the disadvantages caused by the lowering of the curing rate caused by the blending of the antistatic agent (E) by setting the weight average molecular weight of the urethane polyol (A) to a high value and combining the polyfunctional polyol (F) Degradation can be improved. In addition, the pressure-sensitive adhesive of the present embodiment contains the antioxidant (D), so that it is possible to obtain a pressure-sensitive adhesive layer which is less likely to deteriorate releasability after a lapse of a high temperature time.

The pressure-sensitive adhesive of the present embodiment can be used, for example, in a display such as an LCD or OLED having a flat portion or a curved portion, or a touch panel using a related display. In addition, it can be widely used for surface protection of electronic devices such as portable terminals, computers, etc. of portable telephones, smart phones, tablet terminals and the like, which are equipped with such displays or touch panels.

Further, the material of the adherend is not limited to glass, and can be used for protecting materials susceptible to scratches such as polyolefin, gold, silver, copper, and ITO.

Further, the use of the pressure-sensitive adhesive can be applied to, for example, members other than a display, such as window glass, LED, vehicle, wiring, etc., or a laminate thereof.

Further, the adhesive sheet of the present embodiment can be used for protection during the manufacturing process of various members, and for products after the production. It goes without saying that the pressure-sensitive adhesive of the present embodiment can be used in addition to the surface protecting use.

(Urethane polyol (A))

The urethane polyol (A) is a reaction product obtained by subjecting at least one polyol (a) and at least one polyisocyanate (b) to urethanization reaction. The polyisocyanate (b) is preferably a bifunctional isocyanate (b1) having two isocyanate groups in one molecule (also referred to as a diisocyanate). The polyol (a) is preferably a polyol (a1) having at least two hydroxyl groups in one molecule. The isocyanate group (isocyanate group) of the polyisocyanate (b) is used in a molar ratio (NCO / OH ratio) which can be less than the hydroxyl group of the polyol (a). Thereby, a urethane polyol having a hydroxyl group can be obtained. For the urethane reaction, it is preferable to use a catalyst for accelerating the reaction. A solvent may be used for the urethanization reaction, if necessary.

The urethane polyol (A) may be used alone or in combination of two or more.

≪ Polyol (a) >

The polyol (a) is a compound having two or more hydroxyl groups. The polyol (a) is preferably a polyether such as a polyether polyol, a polyester polyol, a polybutadiene modified polyol, a polycarbonate polyol, or a castable polyol, and more preferably a polyether polyol, a polyester polyol or a polybutadiene modified polyol.

The polyol (a) of the present embodiment may be of one type, and if two or more kinds are used in combination, the cohesive force and the adhesive force of the adhesive layer can be easily adjusted. When one type of polyol (a) is used, it is preferable to use a polyol having three or more hydroxyl groups. When two or more polyols (a) are used, it is preferable to use a combination of a polyol having two hydroxyl groups and a polyol having three or more hydroxyl groups. When a polyol having three or more hydroxyl groups is used in combination, it is preferable that the polyisocyanate (b) and the polyol (a) have an NCO / OH ratio (molar ratio) of 0.80 or less. When the NCO / OH ratio (molar ratio) is used in an appropriate range, the reaction can be easily controlled by the synthesis of the urethane polyol (A).

The polyether polyol includes, for example, a reaction product in which an active hydrogen-containing compound having two or more active hydrogens in one molecule is used as an initiator and one or more oxirane compounds are subjected to addition polymerization.

The active hydrogen-containing compound is preferably a hydroxyl group-containing compound, an amine, or the like.

Examples of the hydroxyl group-containing compound include bifunctional active hydrogen-containing compounds such as ethylene glycol (EG), propylene glycol (PG), 1,4-butanediol, neopentyl glycol and butyl ethyl pentanediol; Trifunctional active hydrogen-containing compounds such as glycerin and trimethylolpropane; And quaternary functional hydrogen-containing compounds such as pentaerythritol.

Amines include, for example, bifunctional active hydrogen-containing compounds such as N-aminoethylethanolamine, isophoronediamine, and xylylenediamine; Trifunctional active hydrogen-containing compounds such as triethanolamine; Tetrafunctional active hydrogen-containing compounds such as ethylenediamine and aromatic diamine; And a pentafunctional active hydrogen-containing compound such as diethylenetriamine.

The oxirane compounds include, for example, alkylene oxides (AO) such as ethylene oxide (EO), propylene oxide (PO), and butylene oxide (BO); Tetrahydrofuran (THF) and the like.

It is preferable that the polyether polyol has an alkyleneoxy group derived from an active hydrogen-containing compound in the molecule (this polyol is also referred to as " polyoxyalkylene polyol "). As the hydroxyl group-containing compound constituting the polyoxyalkylene polyol, polyether polyols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol are preferable, and polypropylene glycol which is low in crystallinity and easy to exhibit flexibility is preferable .

The number average molecular weight (Mn) of the polyether polyol is not particularly limited, but is preferably from 200 to 6,000, more preferably from 400 to 5,000, still more preferably from 600 to 4,000, since transparency and flexibility are easy to manifest. By controlling Mn to 200 or more, it is easy to control the reaction during the synthesis of the urethane polyol (A). Further, by setting Mn to 6,000 or less, it is easy to adjust the cohesive force of the urethane polyol (A) to an appropriate range.

The polyester polyol may be, for example, a compound (esterified product) obtained by esterifying at least one polyol component and at least one acid component, or a compound (ring-opened polymerized product) synthesized by ring- desirable.

Examples of the lactone include polycaprolactone, poly (beta -methyl- gamma -valerolactone), polyvalerolactone, and the like.

The polyol component may contain, in addition to the above active hydrogen-containing compounds, diethylene glycol, 1,3-butanediol, 3-methyl-1,5-pentanediol, Diol, 2,4-diethyl-1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 2-ethyl-1,3-hexanediol, 9-nonanediol, 2-methyl-1,8-octanediol, 1,8-decanediol, octadecanediol, hexanetriol and the like.

The acid component may be, for example, succinic acid, methyl succinic acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, 1,12-dodecanedioic acid, 1,14-tetradecanedioic acid dimeric acid, Terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, and 4,4'-biphenyldicarboxylic acid, dimer acid, trimer Acids, and acid anhydrides thereof.

The number average molecular weight (Mn) of the polyester polyol is preferably 200 to 6,000, more preferably 500 to 6,000, still more preferably 500 to 4,000, and particularly preferably 500 to 3,000. By controlling Mn to 200 or more, it is easy to control the reaction during the synthesis of the urethane polyol (A). Further, by setting Mn to 6,000 or less, it is easy to adjust the cohesive force of the urethane polyol (A) to an appropriate range.

The polybutadiene-modified polyol has, for example, at least two terminal hydroxyl groups and has a 1,2-vinyl moiety, a 1,4-cis site, a 1,4-trans site or a structure in which they are hydrogenated, Straight chain or branched polybutadiene.

The number average molecular weight (Mn) of the polybutadiene modified polyol is preferably 200 to 6,000, more preferably 500 to 6,000, still more preferably 500 to 4,000, and particularly preferably 500 to 3,000. By controlling Mn to 200 or more, it is easy to control the reaction during the synthesis of the urethane polyol (A). Further, by setting Mn to 6,000 or less, it is easy to adjust the cohesive force of the urethane polyol (A) to an appropriate range.

The degree of hydrogenation of the polybutadiene-modified polyol is preferably hydrogenated before all of the double bond sites present before hydrogenation. In the present invention, however, some double bond sites may remain.

Other polyols other than the above may be, for example, polycarbonate polyol, castor free polyol and the like. The other polyol is preferably used in combination with a polyether polyol or a polyester polyol.

The number average molecular weight (Mn) of other polyols is about 200 to 6,000.

When the polyol (a) contains an acidic functional group such as a carboxyl group or a sulfo group, it is preferable to use a polyol having no acidic functional group because the adherend may be corroded.

Among them, the polyol (a) is preferably an aliphatic. As a result, the transparency of the adhesive layer can be easily maintained while the re-peeling property after the high-temperature test is further improved.

≪ Polyisocyanate (b) >

As the polyisocyanate (b), for example, known polyisocyanates such as aromatic polyisocyanates, aliphatic polyisocyanates, aromatic aliphatic polyisocyanates, and alicyclic polyisocyanates can be used.

Examples of the aromatic polyisocyanate include 1,3-phenylene diisocyanate, 4,4'-diphenyl diisocyanate, 1,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4- Tolylene diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, 4,4'-triisocyanate isocyanate, 2,6-tolylene diisocyanate, Diphenyl ether diisocyanate, and 4,4 ', 4 "-triphenyl methane triisocyanate.

Examples of the aliphatic polyisocyanate include aliphatic polyisocyanates such as trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, Dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and the like.

Examples of the aromatic aliphatic polyisocyanate include ω, ω'-diisocyanate-1,3-dimethylbenzene, ω'-diisocyanate-1,4-dimethylbenzene, ω, ω'-diisocyanate- 4-diethylbenzene, 1,4-tetramethylxylene diisocyanate, and 1,3-tetramethylxylene diisocyanate.

Examples of the alicyclic polyisocyanate include 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane Diisocyanate, methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4'-methylenebis (cyclohexylisocyanate), 1,4-bis (isocyanatemethyl) cyclohexane, And 1,4-bis (isocyanatomethyl) cyclohexane.

The above polyisocyanate is a diisocyanate, but a triisocyanate obtained by modifying the above diisocyanate can also be used. Examples of the triisocyanate include trimethylolpropane adduct, burette, and trimers of the diisocyanate (the trimer includes an isocyanurate ring).

The polyisocyanate (b) is preferably 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, and 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate).

The polyisocyanate (b) may be used alone or in combination of two or more.

<Catalyst>

The catalyst is preferably, for example, a tertiary amine compound and an organometallic compound.

Examples of the tertiary amine-based compound include triethylamine, triethylenediamine, and 1,8-diazabicyclo (5.4.0) -undecene-7 (DBU).

The organometallic compound is preferably a tin compound or a non-refractory compound.

The tin compound is, for example, dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimaleate, dibutyltin dilaurate (DBTDL), dibutyltin diacetate, di Tributyl tin acetate, tributyl tin acetate, triethyl tin ethoxide, tributyl tin ethoxide, dioctyl tin oxide, tributyltin chloride, tributyltin trichloroacetate, tributyltin trichloride, And 2-ethylhexanoic acid tin.

Examples of non-saponified compounds include titanium-based compounds such as dibutyltitanium dichloride, tetrabutyl titanate, and butoxy titanium trichloride; Lead compounds such as lead oleate, lead 2-ethylhexanoate, lead benzoate, and lead naphthenate; Iron-based compounds such as iron 2-ethylhexanoate and iron acetylacetate; Cobalt compounds such as cobalt benzoate and cobalt 2-ethylhexanoate; Zinc-based compounds such as zinc naphthenate and zinc 2-ethylhexanoate; And zirconium compounds such as zirconium naphthenate. Among them, the tin compound is more preferred because it improves the reaction rate and is less colored.

The catalyst may be used alone or in combination of two or more.

The catalyst is preferably used in an amount of 0.01 to 1.0 part by mass based on 100 parts by mass of the total of the polyisocyanate (b) and the polyol (a).

<Solvent>

For the production of the urethane polyol (A), one or more kinds of solvents may be used, if necessary. Examples of the solvent include ketone solvents such as acetone and methyl ethyl ketone, ester solvents such as ethyl acetate, and hydrocarbon solvents such as toluene and xylene. Among them, an ester solvent, a hydrocarbon solvent and the like are preferable in view of the solubility of the urethane polyol (A) and the boiling point of the solvent.

&Lt; Process for producing urethane polyol (A)

The production method of the urethane polyol (A) is not particularly limited and can be produced by a known polymerization method such as bulk polymerization or solution polymerization.

The order of the manufacturing method is, for example,

(Step 1) A step of collecting one or more polyols (a), one or more polyisocyanates (b), optionally one or more catalysts and, if necessary, one or more solvents, collectively in a flask;

(Step 2) A flask was prepared by preparing one or more polyols (a), optionally at least one catalyst, and optionally at least one solvent, and adding one or more polyisocyanates (b) Order;

(Step 3) A flask is provided with one or more catalysts and, if necessary, one or more kinds of solvents, as required, leaving one or more of the polyols (a) And a step of dropwise adding isocyanate (b) followed by dropwise addition of at least one polyol (a) out of the remaining isocyanate (b).

Among these, it is preferable that the reaction column is easy to control (step 2) (step 3).

When the catalyst is used, the reaction temperature is preferably less than 100 占 폚, more preferably 70 to 95 占 폚. If the reaction temperature is lower than 100 占 폚, side reactions other than the urethane reaction can be suppressed, so that the desired urethane polyol (A) can be easily obtained. When the catalyst is not used, the reaction temperature is preferably 100 占 폚 or higher, and more preferably 110 占 폚 or higher.

The isocyanate group (NCO) of the polyisocyanate (b) and the hydroxyl group (OH) of the polyol (a) in the preparation of the urethane polyol (A) are preferably 0.3 to 0.95 in terms of the molar ratio of NCO / OH, More preferably 0.5 to 0.80, and still more preferably 0.5 to 0.80. The urethane polyol (A) having an appropriate molecular chain can be formed with the NCO / OH ratio falling within the above range, so that the wettability and the productivity are further improved.

When a catalyst is used in the synthesis, it is preferable to inactivate the catalyst. The reaction terminator may be, for example, acetylacetone.

The reaction terminator may be used alone or in combination of two or more.

The weight average molecular weight (Mw) of the urethane polyol (A) is preferably 100,000 to 500,000, more preferably 100,000 to 400,000, and even more preferably 150,000 to 400,000. By adjusting the weight average molecular weight (Mw) in the above range, the pressure-sensitive adhesive layer has a uniform cohesive force immediately after winding, so that the indentation can be suppressed and the yield can be improved.

&Lt; Isocyanate curing agent (B) >

The isocyanate curing agent (B) is a known compound having a plurality of isocyanate groups. The isocyanate curing agent (B) is preferably the above polyisocyanate (b), and among these, aromatic polyisocyanate, aliphatic polyisocyanate, aromatic aliphatic polyisocyanate, and alicyclic polyisocyanate, trimethylolpropane adduct thereof, Burette sieve, and trimerized trifunctional isocyanate thereof are more preferable.

The isocyanate curing agent (B) may be used alone or in combination of two or more.

The blending amount of the isocyanate curing agent (B) is preferably 0.1 part by mass or more and 30 parts by mass or less, more preferably 1 to 25 parts by mass, further preferably 3 to 20 parts by mass, per 100 parts by mass of the urethane polyol (A) And particularly preferably from 5 to 15 parts by mass. When an appropriate amount of the isocyanate curing agent (B) is blended, it is easy to obtain an appropriate adhesive force and cohesive force.

&Lt; Plasticizer (C) >

The pressure-sensitive adhesive of the present embodiment may further include a plasticizer (C). By including the plasticizer (C), the wettability of the adhesive layer to the adherend is further improved. The plasticizer (C) is preferably a fatty acid ester having 8 to 30 carbon atoms, phosphoric acid ester, or the like from the viewpoint of compatibility with other components and the like.

Examples of the fatty acid ester having 8 to 30 carbon atoms include esters of a monobasic acid or a polybasic acid having 6 to 18 carbon atoms and a branched alcohol having a carbon number of 18 or less and an unsaturated Esters of fatty acids or branched acids with up to 4 alcohols, esters of monobasic acids or polybasic acids having 6 to 18 carbon atoms with polyalkylene glycols, fatty acid esters obtained by epoxidation of unsaturated sites with peroxides, and the like.

Examples of esters of monobasic acids or polybasic acids having 6 to 18 carbon atoms and branched alcohols having 18 or less carbon atoms include isostearyl laurate, isopropyl myristate, isocetyl myristate, octyldodecyl myristate Silane, isostearyl palmitate, isocetyl stearate, octyldodecyl oleate, diisostearyl adipate, diisocetyl sebacate, trioleyl trioleate, and triisotetyl trimellitate.

An unsaturated fatty acid having 14 to 18 carbon atoms constituting an ester of an unsaturated fatty acid having 14 to 18 carbon atoms or an alcohol having 4 or less valencies and an alcohol having 4 or less valencies. The unsaturated fatty acid or branched acid having 14 to 18 carbon atoms includes, for example, misteroolic acid, oleic acid, linoleic acid, linolenic acid, isopalmitic acid and isostearic acid. Examples of the alcohols having 4 or less valences include ethylene glycol, propylene glycol, glycerin, trimethylol propane, pentaerythritol, and sorbitan.

Examples of the ester of a monobasic acid or a polybasic acid having 6 to 18 carbon atoms with a polyalkylene glycol include polyethylene glycol such as dicyclyl acid polyethylene glycol, polyethylene glycol di-2-ethylhexylate, polyethylene glycol dilaurylate, polyethylene glycol dioleate, Adipic acid dipropylene glycol methyl ether, and the like.

The fatty acid ester obtained by epoxidizing an unsaturated portion with a peroxide or the like can be obtained by subjecting a compound obtained by epoxidizing an epoxidized oil such as epoxidized soybean oil, epoxidized linseed oil or epoxidized cottonseed oil, or an unsaturated fatty acid having 8 to 18 carbon atoms, And ester compounds with straight chain or branched alcohols of 1 to 6 carbon atoms.

Examples of the phosphate esters include ester compounds of phosphorous acid or phosphoric acid with straight chain or branched alcohols having 2 to 18 carbon atoms.

The plasticizer (C) may be used alone or in combination of two or more.

From the viewpoint of improving the wetting speed, the food (formula weight) to the number average molecular weight (Mn) of the plasticizer (C) is preferably 300 to 1000, more preferably 300 to 900, still more preferably 350 to 850.

The blending amount of the plasticizer (C) is preferably 0.1 to 100 parts by mass, more preferably 1 to 80 parts by mass, and still more preferably 5 to 60 parts by mass with respect to 100 parts by mass of the urethane polyol (A). When an appropriate amount of the plasticizer (C) is blended, the wettability is further improved.

&Lt; Antioxidant (D) >

The pressure sensitive adhesive of the present embodiment includes an antioxidant (D). When the antioxidant (D) is contained, thermal decomposition of the crosslinking network of the urethane polyol (A) and the isocyanate curing agent (B) can be suppressed, so that an adhesive layer hardly deteriorating releasability after a lapse of a high temperature time can be obtained.

Examples of the antioxidant (D) include a radical chain inhibitor such as a phenol antioxidant and an amine antioxidant, a sulfur antioxidant, and a phosphorus antioxidant. Among them, a phenol-based antioxidant is preferable.

Phenolic antioxidants include, for example, 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6- - (3,5-di-t-butyl-4-hydroxyphenyl) propionate; (4-methyl-6-t-butylphenol), 2,2'-methylenebis (4-ethyl- Butylphenol), 4,4'-butylidenebis (3-methyl-6-t-butylphenol), and 3,9-bis [1,1- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] 2,4,8,10-tetraoxaspiro [5,5] undecane; Methyl-4-hydroxy-5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane, bis [3,3' (3'-hydroxy-3'-t-butylphenyl) butylic acid] glycol ester and 1,3,5-tris (3 ', 5'-di- Phenoxybenzene) -s-triazine-2,4,6- (1H, 3H, 5H) trione, and tocopherol.

The sulfur-based antioxidant may be, for example, dilauryl 3,3'-thiodipropionate, dimyristyl 3,3'-thiodipropionate, and distearyl 3,3'-thiodipropionate Nate and so on.

Examples of the phosphorus antioxidant include triphenyl phosphite, diphenyl isodecyl phosphite, and phenyl diisodecyl phosphite.

The antioxidant (D) may be used alone or in combination of two or more.

The blending amount of the antioxidant (D) is preferably 0.1 to 10 parts by mass, more preferably 0.3 to 5 parts by mass, further preferably 0.5 to 3 parts by mass, per 100 parts by mass of the urethane polyol (A).

&Lt; Antistatic Agent (E) >

The pressure sensitive adhesive of the present embodiment includes an antistatic agent (E). When the antistatic agent (E) is included, it is easy to suppress the electrostatic discharge when peeling the pressure-sensitive adhesive sheet, and to prevent damage to electronic parts and the like coupled to, for example, a display.

Examples of the antistatic agent include an inorganic salt, an ionic liquid, an ionic solid, and a surfactant. Of these, ionic liquids are preferred. The &quot; ionic liquid &quot; is also referred to as a room-temperature molten salt, and exhibits liquid properties at 25 ° C.

Inorganic salts include, for example, sodium chloride, potassium chloride, lithium chloride, lithium perchlorate, ammonium chloride, potassium chloride, aluminum chloride, copper chloride, ferrous chloride, ferric chloride, ammonium sulfate, potassium nitrate, sodium nitrate, And sodium benzoate.

The ionic liquid is a salt of an anion and a cation, and the cation is preferably an imidazolium ion, a pyridinium ion, an ammonium ion or the like.

The ionic liquid containing the imidazolium ion is, for example, 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide, 1,3-dimethylimidazolium bis (trifluoro Methylsulfonyl) imide, and 1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide.

The ionic liquid containing a pyridinium ion is, for example, 1-methylpyridinium bis (trifluoromethylsulfonyl) imide, 1-butylpyridinium bis (trifluoromethylsulfonyl) Hexylpyridinium bis (trifluoromethylsulfonyl) imide, 1-octylpyridinium bis (trifluoromethylsulfonyl) imide, 1-hexyl-4-methylpyridinium bis 4-methylpyridinium bis (trifluoromethylsulfonyl) imide, 1-octyl-4-methylpyridinium bis (trifluoromethylsulfonyl) imide, (Perfluorobutylsulfonyl) imide, 1-methylpyridinium bis (perfluoroethylsulfonyl) imide, and 1-methylpyridinium bis (perfluorobutylsulfonyl) imide.

The ionic liquid containing an ammonium ion is, for example, trimethylheptylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N-propylammonium bis (trifluoromethanesulfonyl) N, N-diethyl-N-methyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, Fluoromethanesulfonyl) imide, and tri-n-butylmethylammonium bistrifluoromethane sulfonimide.

Other known ionic liquids such as pyrrolidinium ions, phosphonium ions, and sulfonium ions can be suitably used as the cation.

The ionic solid, like the ionic liquid, is a salt of cation and anion, but exhibits a solid state at 25 ° C under atmospheric pressure. The cation is preferably, for example, an alkali metal ion, a phosphonium ion, a pyridinium ion, or an ammonium ion.

Ionic solids containing alkali metal ions include, for example, lithium bistrifluorosulfonylimide, lithium bistrifluoromethylsulfonylimide, lithium bispentafluoroethylsulfonylimide, lithium bisheptafluoropropyl Sodium bistrifluoromethylsulfonylimide, sodium bispentafluoroethylsulfonylimide, sodium bis-trifluoromethylsulfonylimide, sodium bis-trifluoromethylsulfonylimide, sodium bis-trifluoromethylsulfonylimide, sodium bis- Heptafluoropropylsulfonylimide, sodium bisnonanfluorobutylsulfonylimide, potassium bis-fluorosulfonylimide, potassium bistrifluoromethylsulfonylimide, potassium bispentafluoroethylsulfonylimide, potassium bis- Amide, potassium bisheptafluoropropylsulfonylimide, and potassium bisnonan fluorobutylsulfonylimide.

Ionic solids comprising a phosphonium ion can be, for example, tetrabutylphosphonium bis-fluorosulfonylimide, tetrabutylphosphonium bistrifluoromethylsulfonylimide, tetrabutylphosphonium bis pentafluoroethylsulfide Tetrabutylphosphonium bromide, tetrabutylphosphonium bisheptafluoropropylsulfonylimide, tetrabutylphosphoniumbisonan fluorobutylsulfonylimide, tributylhexadecylphosphoniumbisfluorosulfonylimide, tributylhexa Decylphosphonium bistrifluoromethylsulfonylimide, tributylhexadecylphosphonium bis pentafluoroethylsulfonylimide, tributylhexadecylphosphoniumbisheptafluoropropylsulfonylimide, tributylhexadecylphosphine Sulfonium iodide, phosphonium iodide, sulfonium iodide, phosphonium iodide, phosphonium iodide, phosphonium iodide, Imide, tetraoctylphosphonium bispentafluoroethylsulfonylimide, tetraoctylphosphoniumbisheptafluoropropylsulfonylimide, tetraoctylphosphoniumbisnanofluorobutylsulfonylimide, and the like can be given. .

Ionic solids containing pyridinium ions include, for example, 1-hexadecyl-4-methylpyridinium bis-fluorosulfonylimide, 1-hexadecyl-4-methylpyridinium bistrifluoromethylsulfonyl 1-hexadecyl-4-methylpyridinium bispentafluoroethylsulfonylimide, 1-hexadecyl-4-methylpyridinium bisheptafluoropropylsulfonylimide, 1-hexadecyl-4-methyl Pyridiniumbisonan fluorobutylsulfonylimide, and the like.

Ionic solids containing ammonium ions include, for example, tributylmethylbistrifluoromethylsulfonylimide, tributylmethylbispentafluoroethylsulfonylimide, tributylmethylbisheptafluoropropylsulfonylmethane, Amide, tributylmethylbisnonorfluorobutylsulfonylimide, octyltributylbistrifluoromethylsulfonylimide, octyltributylbispentafluoroethylsulfonylimide, octyltributylbisheptane But are not limited to, fluoropropylsulfonylimide, octyltributylbisonan fluorobutylsulfonylimide, tetrabutylbisfluorosulfonylimide, tetrabutylbistrifluoromethylsulfonylimide, tetrabutylbispentafluoro Tetrabutylbisheptafluoropropylsulfonylimide, tetrabutylbisnonan fluorobutylsulfonylimide, and the like can be given.

Other known ionic solid such as pyridinium ion, imidazolium ion, and sulfonium ion can be suitably used.

Surfactants can be classified into non-ionic, anionic, cationic, and positive types.

Examples of the nonionic surfactant include glycerin fatty acid esters, polyoxyalkylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl amines, polyoxyethylene alkylamine fatty acid esters, fatty acid diethanol amides, polyether esters Amide type, ethylene oxide-epichlorohydrin type, and polyether ester type.

Anionic surfactants (excluding ionic liquids and ionic solids) are, for example, alkyl sulfonates, alkylbenzenesulfonates, alkyl phosphates, and polystyrene sulfonate types.

Examples of the cationic surfactant include tetraalkylammonium salts, trialkylbenzylammonium salts, and quaternary ammonium salt group-containing acrylate polymer types.

Amphoteric surfactants include, for example, amino acid type amphoteric surfactants such as alkyl betaine and alkyl imidazolium betaine and higher alkylaminopropionic acid salts, higher alkyl dimethyl betaine, and higher alkyl dihydroxyethyl betaine Beta-type amphoteric surfactants, and the like.

The antistatic agent (E) is liquid or solid at 25 캜.

The antistatic agent (E) of the liquid at 25 캜 is easy to shift to the interface between the pressure-sensitive adhesive layer and the adherend as compared with the solid, so that it is easy to obtain better antistatic property.

In addition, the antistatic agent (E) as a solid at 25 占 폚 tends to exist as an island of a sea-island structure in the adhesive layer as compared with a liquid. As a result, the stress relaxation property of the pressure-sensitive adhesive layer is improved, so that good adhesion of the substrate can be easily obtained.

Among them, the antistatic agent (E) is preferably 1-octyl-4-methylpyridinium bis (fluorosulfonyl) imide or tetrabutylphosphonium bis (trifluoromethanesulfonylimide).

The antistatic agent (E) may be used alone or in combination of two or more.

The blending amount of the antistatic agent (E) is preferably 0.01 to 3 parts by mass, more preferably 0.03 to 2 parts by mass, further preferably 0.06 to 1 part by mass, per 100 parts by mass of the urethane polyol (A). When an appropriate amount of the antistatic agent (E) is blended, the re-peelability after a lapse of a high temperature time is hardly lowered, and the yield in the production of the pressure-sensitive adhesive sheet is further improved.

&Lt; Polyfunctional polyol (F) >

The multifunctional polyol (F) of the present embodiment reacts with the isocyanate curing agent (B) together with the urethane polyol (A) to form a segment having a high cross-linking density in the cross-linking structure of the adhesive layer. The segment having a high cross-linking density has a low molecular weight immediately before the reaction and has an excellent surface orientation, and makes the surface of the coating film strong, thereby reducing the indentation. The polyfunctional polyol (F) can utilize or newly form the residual polyol (a) in synthesizing the urethane polyol (A). Further, the residual polyol (a) may be used in combination with a new formulation.

As the polyfunctional polyol (F), a polyol having three or more hydroxyl groups in one molecule among the polyols (a) already described can be used. By setting the number of hydroxyl groups in one molecule to 3 or more, a segment having a high cross-linking density on the surface of the pressure-sensitive adhesive layer can be appropriately adjusted, thereby further reducing the indentation.

In the case of using a polyol having a primary hydroxyl group at the end of the polyfunctional polyol (F), the curing rate with the isocyanate curing agent (B) is increased, so that the indentation is suppressed and the yield tends to be further improved.

When a polyol having a secondary hydroxyl group at the molecular end is used as the polyfunctional polyol (F), it takes a long time until completion of crosslinking, so that a pressure-sensitive adhesive layer with little hardening deformation can be formed. Thereby, the pressure-sensitive adhesive layer may be sufficiently adhered to a substrate which has not undergone easy adhesion treatment such as corona treatment.

The polyfunctional polyol (F) preferably contains 2 to 50 parts by mass, more preferably 2 to 30 parts by mass, and further preferably 4 to 20 parts by mass with respect to 100 parts by mass of the urethane polyol (A). By containing the polyfunctional polyol (F) in an amount of 2 to 50 parts by mass, the proportion of the segment having a high crosslinking density on the surface of the pressure-sensitive adhesive layer can be appropriately adjusted, thereby further reducing the indentation.

As the polyfunctional polyol (F), those having three or more hydroxyl groups in one molecule and having a primary or secondary hydroxyl group at the end of the molecule, among the polyols (a) listed above, can be used. Especially preferred are polyester polyols or polyether polyols.

The number average molecular weight (Mn) of the polyfunctional polyol (F) is preferably in the range of 500 to 6,000, more preferably 1,000 to 5,000, and still more preferably 1,000 to 4,000. When the molecular weight is more than 500, the generation of microgels locally reacted with the isocyanate curing agent (B) can be inhibited. When the molecular weight is 6,000 or less, the molecular weight between the cross-linking moieties can be reduced. Therefore, indentation can be suppressed and the re- do.

<Solvent>

As the solvent, a solvent used in the production of the urethane polyol (A) can be used, but an ester solvent, a hydrocarbon solvent and the like are preferable. The solvent may be used alone or in combination of two or more.

<Other additives>

The pressure-sensitive adhesive of the present embodiment may contain other additives if necessary within the range in which the problems can be solved. Other additives include, for example, resins, fillers, metal powders, pigments, foils, softeners, ultraviolet absorbers, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, , Lubricants, and the like.

As the filler, for example, talc, calcium carbonate, titanium oxide and the like can be mentioned.

Examples of the ultraviolet absorber include a benzophenone ultraviolet absorber, a benzotriazole ultraviolet absorber, a salicylic acid ultraviolet absorber, an oxalic anilide ultraviolet absorber, a cyanoacrylate ultraviolet absorber, and a triazine-based ultraviolet absorber.

Examples of the benzophenone ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2- 4-dodecyloxybenzophenone, 2,2'-dihydroxy-4-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy- Methoxy-5-sulfobenzophenone, and bis (2-methoxy-4-hydroxy-5-benzoylphenyl) methane.

Examples of the benzotriazole ultraviolet absorber include 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-tert- butylphenyl) benzotriazole, Butylphenyl) benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5- Chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di (tert-butylphenyl) 2'-hydroxy-3 '- (3' ', 4' '- benzotriazole), 2- (2'- , 5 ", 6" -tetrahydrophthalimidemethyl) -5'-methylphenyl] benzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl) - Benzotriazol-2-yl) phenol] and 2 (2'-hydroxy-5 '- (meth) acryloxyphenyl) -2H-benzotriazole.

Examples of the salicylic acid-based ultraviolet absorber include phenyl salicylate, p-tert-butylphenyl salicylate, and p-octylphenyl salicylate.

Examples of the cyanoacrylate ultraviolet absorber include 2-ethylhexyl-2-cyano-3,3'-diphenylacrylate, and ethyl-2-cyano-3,3'-diphenylacrylate And so on.

Examples of the light stabilizer include hindered amine light stabilizers and ultraviolet stabilizers.

Examples of the hindered amine light stabilizer include [bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate], bis (1,2,2,6,6-pentamethyl -4-piperidyl) sebacate, and methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate.

Ultraviolet stabilizers include, for example, nickel bis (octylphenyl) sulfide, [2,2'-thiobis (4-tert-octylphenolate)] n-butylamine nickel, nickel complex- tert-butyl-4-hydroxybenzyl-phosphate monoethylate, nickel-dibutyldithiocarbamate, benzoate type quencer, and nickel-dibutyldithiocarbamate.

Leveling agents include acrylic leveling agents, fluorine leveling agents, silicone leveling agents, and the like. As an example of a commercially available leveling agent, the acrylic leveling agent may be, for example, Polyflow No.36, Polyflow No.56, Polyflow No. 85HF, Polyflow No. 99C (all manufactured by Kyoka Kagaku Co., Ltd.) . Examples of the fluorine leveling agent include MEGAFACE F470N and MEGAFACE F556 (both manufactured by DIC). As the silicon leveling agent, for example, Grandyd PC4100 (manufactured by DIC) can be mentioned.

<Adhesive sheet>

The pressure-sensitive adhesive sheet of the present embodiment is provided with a substrate and a pressure-sensitive adhesive layer which is a cured product of the pressure-sensitive adhesive. The adhesive layer may be formed on one or both surfaces of the substrate. The surface of the adhesive layer that is not in contact with the substrate is protected with a release sheet until just before use in order to prevent adhesion of foreign matter.

The base material is not limited to a flexible sheet and a sheet material. Examples of the substrate include plastic, paper, and metal foil, and laminated substrates thereof.

In order to improve the adhesion, a simple bonding treatment such as dry treatment such as corona discharge treatment or wet treatment such as application of an anchor coating agent can be performed beforehand on the surface of the substrate in contact with the adhesive layer.

The plastic material of the base material is, for example, an ester-based resin such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); Olefin resins such as polyethylene (PE), polypropylene (PP), and cycloolefin polymer (COP); Vinyl-based resins such as polyvinyl chloride; Amide resins such as nylon 66; Urethane resin (including foam); And so on.

The thickness of the substrate is generally about 10 to 300 mu m. Further, when a polyurethane sheet (including a foamed material) is used for the substrate, the thickness is usually about 20 to 50,000 mu m. Examples of the paper include plain paper, coated paper, and art paper. Examples of the metal foil include aluminum foil and copper foil.

As the release sheet, a known release sheet on which a known release treatment such as a silicone release agent is applied to the surface of plastic or paper can be used.

The pressure-sensitive adhesive sheet can be produced by, for example, a method of forming a coating layer on the surface of a substrate to form a coating layer, followed by drying and curing the coating layer to form a pressure-sensitive adhesive layer. The heating and drying temperature is generally about 60 to 150 ° C. The thickness of the adhesive layer is generally about 0.1 to 200 mu m.

Examples of the application method include known methods such as a roll coater method, a comma coater method, a die coater method, a reverse coater method, a silk screen method, and a gravure coater method.

Further, contrary to the above-mentioned method, the pressure-sensitive adhesive layer is formed on the surface of the release sheet to form a coated layer, and then the coated layer is dried and cured to form an adhesive layer made of the cured product of the pressure- And a method of attaching a substrate to the exposed surface of the layer. When a release sheet is pasted in place of the substrate by the above method, a release sheet, a pressure-sensitive adhesive layer, or a release sheet is obtained.

<Laminate>

The laminate of the present embodiment includes a member selected from the group consisting of a transparent conductive film, glass, acrylic plate, polycarbonate plate, olefin plate, and inorganic barrier layer, and an adhesive sheet.

Since the laminate includes the pressure-sensitive adhesive sheet formed of the pressure-sensitive adhesive of the present embodiment, for example, it is possible to protect the members of the display which are likely to be broken when the display is manufactured, and to easily peel off after manufacture. The display is, for example, an LCD, an OLED or the like, and many touch panels are provided as other members.

The touch panel is provided with, for example, a transparent electrode film. The transparent electrode film is a film formed by sputtering or vapor deposition of a conductive layer of ITO (indium tin oxide) or the like on the surface of a transparent film such as polyethylene terephthalate (PET) at a thickness of about 0.1 to 0.3 mu m. The conductive layer (electrode layer) formed of ITO or the like is liable to be broken. Therefore, when the pressure-sensitive adhesive sheet is provided, the conductive layer is hardly damaged by handling such as transportation and processing.

The OLED has an inorganic barrier layer to protect the light-emitting element that is susceptible to deterioration. The inorganic barrier layer is, for example, a layer having a thickness of about 15 to 100 nm, which is formed by vapor deposition or sputtering of an inorganic compound such as silicon nitride. Accordingly, when the pressure-sensitive adhesive sheet is provided, the inorganic barrier layer is less likely to be damaged due to handling and transportation of the OLED.

Glass, an acrylic plate, a polycarbonate plate, and an olefin plate are optical members constituting a part of a laminate constituting a display such as an LCD and an OLED. The optical member is used, for example, for protection of a liquid crystal element or for a surface of a touch panel. Since the touch panel requires a thin thickness, the optical member is also thin and easily damaged. Therefore, when the pressure sensitive adhesive sheet is provided, it is difficult for the optical member to be damaged by handling such as transportation and processing of the touch panel. The optical member may have optical functions such as a hard coating, a retardation, and a polarizing plate. The thickness of the optical member is about 10 to 1000 占 퐉.

[Example]

Hereinafter, embodiments of the present invention will be described with reference to examples. Needless to say, embodiments of the present invention are not limited to the embodiments. Hereinafter, &quot; part &quot; means &quot; part by mass &quot;. In addition, "%" means "% by mass". Incidentally, the blending amount in the table is parts by mass.

[Synthesis Example of Urethane Polyol (A)] [

(Synthesis Example 1)

500 parts of Kuraraypolyol P-1010 (bifunctional polyesterpolyol, manufactured by Kuraray Co., Ltd.) and 6 parts of Kuraraypolol F-1010 (manufactured by Kuraray Co., Ltd.) were added to a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer and dropping funnel 500 parts of hexamethylene diisocyanate, 760 parts of toluene, and 0.05 part of dioctyltin dilaurate as catalysts. The temperature was gradually raised to 75 占 폚, and the reaction was carried out for 3 hours. After confirming that the NCO characteristic absorption (2,270 cm ^-1 ) of the IR chart was lost, the system was cooled to 30 ° C and the reaction was terminated. The urethane polyol (A1) had a weight average molecular weight (Mw) of 150,000 and a conversion rate of more than 99%.

(Synthesis Examples 2 to 36, 38 and 39)

The urethane polyol (A) of each of Synthesis Examples 2 to 36, 38 and 39 was obtained in the same manner as in Synthesis Example 1 except that the materials and mixing ratios of Example 1 were changed as shown in Table 1-4. Table 1 shows Mw and conversion ratio of the obtained urethane polyol (A). In addition, the blending amount of the raw materials in the table is converted into nonvolatile content, and the unit of numerical value not otherwise specified is [parts].

(Synthesis Example 37)

200 parts of Kurare Polyol P-1010 (bifunctional polyester polyol, manufactured by Kuraray Co., Ltd.), Exenol 240 (trifunctional polyether polyol, 2-ethylhexyl acrylate) were added to a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer and dropping funnel. Manufactured by Asahi Glass Co., Ltd.), 70 parts of hexamethylene diisocyanate, 547 parts of toluene and 0.05 part of dioctyltin dilaurate as a catalyst were prepared, and the temperature was gradually raised to 90 占 폚 and reaction was carried out for 30 minutes. Thereafter, a mixed solution of 100 parts of Kurare Polyol P-1010, 150 parts of Exenol 240 and 167 parts of toluene was added dropwise in a dropping funnel over 30 minutes. After confirming that the NCO characteristic absorption (2,270 cm ^-1 ) of the IR chart was lost, the system was cooled to 30 ° C and the reaction was terminated. The urethane polyol (A37) had an Mw of 210,000 and a conversion of 90%.

[material]

The materials used in the table are as follows.

&Lt; Polyol (a) >

(a1): P1010 ("Kurare Polyol P-1010", polyester polyol, Mn1000, hydroxyl number 2, primary hydroxyl group, Kurarese)

(a2): P3199 ("Preplast 3199", polyester polyol, Mn2000, number of hydroxyl groups 2, primary hydroxyl group, product of CRODA)

(a3): PP1000 ("SANNIX PP-1000", polyoxypropylene glycol, Mn1000, hydroxyl number 2, secondary hydroxyl group, manufactured by Sanyo Chemical Industries, Ltd.)

(a4): PP2000 ("SANNIX PP-2000", polyoxypropylene glycol, Mn2000 hydroxyl number 2, secondary hydroxyl group, manufactured by Sanyo Chemical Industries, Ltd.)

(a5): EXE 510 ("Exenol 510", polyether polyol, Mn 4000, hydroxyl number 2, primary hydroxyl group, product of Asahi Glass Co., Ltd.)

(a6): GI1000 ("NISSO-PB GI-1000", terminal hydrogenated polybutadiene, Mn1500, hydroxyl number 2, primary hydroxyl group, manufactured by Nippon Soda Co., Ltd.)

(a7): GI3000 ("NISSO-PB GI-3000", terminal hydrogenated polybutadiene, Mn3100, hydroxyl number 2, primary hydroxyl group, manufactured by Nippon Soda Co., Ltd.)

(a8): HLBH P2000 ("Krasol (registered trademark) HLBH P2000", terminal hydroxyl group denaturated liquid polybutadiene, Mn2000, hydroxyl number 1.95, primary hydroxyl group, CRAY VALLEY)

(a9): F1010 ("Kuraraypolyol F-1010", polyester polyol, Mn1000, hydroxyl number 3, primary hydroxyl group, manufactured by Kuraray Co.)

(a10): F3010 (&quot; Kuraraypolyol F-3010 &quot;, polyester polyol, Mn3000, number of hydroxyl groups 3, primary hydroxyl group, available from Kuraray Co.)

(a11): Exe 1030 ("Exenol 1030", polyether polyol, Mn1000, hydroxyl number 3, secondary hydroxyl group, product of Asahi Glass Co., Ltd.)

(a12): Exe 240 ("Exenol 240", polyether polyol, Mn3000, hydroxyl number 3, primary hydroxyl group, product of Asahi Glass Co., Ltd.)

(a13): EXE 4030 (&quot; EXCENOL 4030 &quot;, polyether polyol, Mn 4000, hydroxyl number 3, water-feeding acid group, available from Asahi Glass Co., Ltd.)

(a14): Exe 828 ("Exenol 828", polyether polyol, Mn5000, hydroxyl number 3, primary hydroxyl group, product of Asahi Glass Co., Ltd.)

(a15): P3010 ("Kuraraypolyol P-3010", polyester polyol, Mn1000, hydroxyl number 3, primary hydroxyl group, manufactured by Kuraray Co.)

(a16): GP3000 ("Sanix GP-3000", polyether polyol, Mn3000, hydroxyl number 3, secondary hydroxyl group, manufactured by Sanyo Chemical Industries, Ltd.)

(a17): AM302 ("Adeka polyether AM-302", polyether polyol, Mn3000, hydroxyl number 3, primary hydroxyl group, manufactured by ADEKA)

(a18): PTMG1000 ("PTMG1000", polytetramethylene ether glycol, Mn1000, hydroxyl number 2, primary hydroxyl group, available from Mitsubishi Chemical Corporation)

(a19): S3011 ("FREMINOL S-3011", polyether polyol, Mn10000, hydroxyl number 3, secondary hydroxyl group, product of Asahi Glass Co., Ltd.)

(a20): GP1000 ("Sanix GP-1000", polyether polyol, Mn1000, hydroxyl number 3, secondary hydroxyl group, manufactured by Sanyo Chemical Industries, Ltd.)

&Lt; Polyisocyanate (b) >

(b1): HDI (hexamethylene diisocyanate, "Desmodule H" manufactured by Sumikako Vestrol Urethane Co., Ltd.)

(b2): TDI ("Deodmodule T-80" manufactured by Sumikako Best Urethane Co., Ltd.)

&Lt; Isocyanate curing agent (B) >

(B1): an HDI adduct ("Sumidur HT", trimethylol propane adduct of hexamethylene diisocyanate, Sumikako Best Urethane Co., Ltd.)

(B2): HDI Nutrite (Sumidur N3300, Nylate of hexamethylene diisocyanate, Sumikako Best Urethane Co., Ltd.)

&Lt; Plasticizer (C) >

(C1): M182A (&quot; Unistar M182A &quot;, methyl oleate, Nichia)

(C2): W262 ("Monoisizer W262", ether ester plasticizer, manufactured by DIC)

(C3): D55 ("Adekaizer D-55", an epoxidized fatty acid alkyl ester, manufactured by ADEKA)

(C4): TOP ("TOP", tris (2-ethylhexyl) phosphate, manufactured by Daihachi Kikkakagakusha)

(C5): IPP ("Exepal IPP", isopropyl palmitate, available from Kao Corporation)

&Lt; Antioxidant (D) >

(D): Irg1010 ("Irganox 1010", pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] )

(D2): IrgL135 ("Irganox L135", benzenepropanoic acid 3,5-bis (1,1-dimethyl-ethyl) -4-hydroxy-, C7-C9 branched alkyl ester, phenol- Ltd.)

&Lt; Antistatic Agent (E) >

(E1): TFSI · ammonium salt (tri-n-butylmethylammonium · bistrifluoromethanesulfonimide, ionic liquid)

(E2): TFSI · Lithium salt (lithium · bistrifluoromethanesulfonylimide, ionic solid)

(E3): FSI · pyridinium salt (1-octyl-4-methylpyridinium · bis-fluorosulfonylimide, ionic liquid)

(E4): FSI · imidazolium salt (1-ethyl-3-methyl-imidazolium · bisfluorosulfonylimide, ionic liquid)

(E5): TFSI · Phosphonium salt (tetrabutylphosphonium · bistrifluoromethanesulfonylimide, ionic solid)

&Lt; Polyfunctional polyol (F) >

The above (a9) to (a20) were also used as polyfunctional polyols.

[Measurement of weight average molecular weight (Mw) and number average molecular weight (Mn)] [

The weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured by a gel permeation chromatography (GPC) method. The measurement conditions are as follows. Further, both Mw and Mn are values in terms of polystyrene.

<Measurement Conditions>

Device: SHIMADZU Prominence (manufactured by Shimadzu Seisakusho),

Column: Three SHODEX LF-804 (manufactured by Showa Denko KK) are connected in series,

Detector: differential refractive index detector

Solvent: tetrahydrofuran (THF)

Flow rate: 0.5 mL / min

Solvent temperature: 40 캜

Sample concentration: 0.1%

Sample injection amount: 100 μL

[Table 1]

[Table 2]

[Table 3]

[Table 4]

(Example 1)

100 parts of the urethane polyol (A1) obtained in Synthesis Example 1, 2 parts of the isocyanate curing agent (B1), 30 parts of the plasticizer (C1), 0.7 part of the antioxidant (D1), 0.1 part of the antistatic agent (E1) a12) and 100 parts of ethyl acetate as a solvent were mixed and stirred with a disper to obtain a pressure-sensitive adhesive. The amount of each material except for the solvent represents the nonvolatile matter-converted value [part].

Polyethylene terephthalate (PET) ("Lumirra T-60", manufactured by Doraisha) having a thickness of 50 μm was prepared on the substrate. The obtained pressure-sensitive adhesive was coated on the substrate using a Comma Coater (registered trademark) at a coating speed of 3 m / min and a width of 30 cm to form a coating layer having a thickness of 12 Pm to form a coating layer.

Then, the formed coating layer was dried using a drying oven at 100 DEG C for 1 minute to form an adhesive layer. A commercially available release sheet having a thickness of 38 탆 was applied on the adhesive layer and cured for one week under the condition of 23 캜 -50% RH to obtain a pressure-sensitive adhesive sheet.

(Examples 2 to 73 and Comparative Examples 1 to 5)

The pressure-sensitive adhesives and pressure-sensitive adhesive sheets of Examples 2 to 73 and Comparative Examples 1 to 5 were obtained in the same manner as in Example 1, except that the materials and mixing ratios of Example 1 were changed as shown in Table 5-13.

[Evaluation Items and Evaluation Methods]

Evaluation items and evaluation methods of the obtained pressure-sensitive adhesive and pressure-sensitive adhesive sheet are as follows.

(Indentation)

A pressure-sensitive adhesive sheet was produced in the same manner as in Example 1 except that the coating speed was changed to 30 m / minute and the width was changed to 150 cm, and a trace (indentation) of the tape connecting the winding roll and the pressure- I appreciated. The evaluation criteria are as follows.

◎: No trace of tape is seen at 10m. rainfall.

○: No trace of tape is seen at the point of 25m. Good.

△: No trace of tape is seen at 50m. Practical.

×: A tape mark is seen at 50 m. Not practicable.

(Re-peelability after elapse of high temperature time)

The re-peelability after the lapse of the high temperature time was evaluated by the adhesive force.

The resulting pressure-sensitive adhesive sheet was prepared in a size of 25 mm in width and 100 mm in length, and used as a measurement sample. Then, the release sheet was peeled off from the measurement sample in an atmosphere of 23 ° C-50% RH, and the exposed adhesive layer was bonded to a caustic soda glass plate, followed by compression and compression of 2 kg rolls one time. Thereafter, it was allowed to stand under the condition of 100 캜 for 24 hours. Subsequently, the substrate was air-cooled for 30 minutes in an atmosphere of 23 ° C and 50% RH. Thereafter, the adhesive force was measured using a tensile tester (Tensilon: Orientech) according to JIS Z0237 under the conditions of a peeling speed of 300 mm / min and a peeling angle of 180 ° Respectively. Adhesive force was measured in the same manner as above except that the adherend was changed to an ITO film ("Tetorite TCF", product of Oikeco) and PET ("Lumirra T-60", manufactured by Dorey).

The evaluation criteria are as follows.

?: Less than 100 mN / 25 mm. rainfall.

○: 100 mN / 25 mm or more and less than 200 mN / 25 mm. Good.

?: 200 mN / 25 mm or more and 300 mN / 25 mm or less. Practical.

×: more than 300 mN / 25 mm. Not practicable.

(Adherend staining property)

The stain resistance derived from the pressure-sensitive adhesive was evaluated with respect to the ITO surface after the &quot; re-peelability after the lapse of the high temperature time &quot;.

Evaluation was carried out by irradiating the object with LED light from the dark room to the naked eye. The evaluation criteria are as follows.

○: No contamination is recognized at all. Good.

?: Slight cloudiness is recognized. Practical.

X: Clear cloudiness is recognized. Not practicable.

(Substrate adhesion)

The resulting pressure-sensitive adhesive sheet was prepared in a size of 50 mm in width and 50 mm in length, and used as a measurement sample. Then, the release sheet is peeled off from the measurement sample under an atmosphere of 23 ° C-50% RH, and eleven shears are inserted in the adhesive layer at a distance of 2 mm until reaching the substrate with the knife but not cutting. Next, in the direction perpendicular to the sheath, eleven sheaves were inserted in the same manner as above to form 100 cells in a checkerboard shape. When the adhesive layer was strongly rubbed ten times with a thumb, the number of the chambers left without leaving the adhesive layer from the substrate was evaluated. The evaluation criteria are as follows.

◎: 100 left. rainfall.

○: More than 90 spaces and less than 100 spaces remaining. Good.

△: More than 75 spaces and less than 90 spaces remaining. Practical.

X: Less than 75 remaining squares. Not practicable.

(Antistatic property)

The resulting pressure-sensitive adhesive sheet was prepared in a size of 50 mm in width and 50 mm in length, and used as a measurement sample. Subsequently, the release sheet was peeled off from the measurement sample under an atmosphere of 23 ° C-50% RH, and a probe of a surface resistance meter (Hiesta-UX MCP-HT800, manufactured by Mitsubishi Chemical Analytech Co., Ltd.) The value was evaluated. The evaluation criteria are as follows.

◎: The surface resistance value is less than 8 × 1 × 10. rainfall.

○: The surface resistance value is not less than 8 × 10 × 10 × 10 × 10. Good.

DELTA: The surface resistance value is not less than 9 x 10 &lt; 10 &gt; Practical.

X: 10 or more in surface resistance value of 1 x 10. Not practicable.

[Table 5]

[Table 6]

[Table 7]

[Table 8]

[Table 9]

[Table 10]

[Table 11]

[Table 12]

[Table 13]

Claims (8)

(A), an isocyanate curing agent (B), an antioxidant (D), an antistatic agent (E) and a polyfunctional polyol (B) having a weight average molecular weight of 100,000 to 500,000, which are reactants of the polyol (a) and the polyisocyanate (F).
The method according to claim 1,
Wherein the polyfunctional polyol (F) has a hydroxyl number of 3 or more in one molecule.
The method according to claim 1,
A pressure-sensitive adhesive further comprising a plasticizer (C).
The method of claim 3,
And 0.1 to 100 parts by mass of the plasticizer (C) relative to 100 parts by mass of the urethane polyol (A).
The method according to claim 1,
And 2 to 50 parts by mass of the polyfunctional polyol (F) relative to 100 parts by mass of the urethane polyol (A).
The method according to claim 1,
The polyfunctional polyol (F) has a primary hydroxyl group at the terminal.
And a pressure-sensitive adhesive layer as a cured product of the pressure-sensitive adhesive according to any one of claims 1 to 6.
A member selected from the group consisting of a transparent conductive film, glass, an acrylic plate, a polycarbonate plate, an olefin plate, and an inorganic barrier layer, and the adhesive sheet according to claim 7.