JP2018016730A - Pressure-sensitive adhesive and adhesive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure-sensitive adhesive which is excellent in re-peelability when used as an adhesive film and prevents floating and peeling from an adherend after exposed under high temperature environment and high temperature and high humidity environment, and to provide an adhesive film using the same.SOLUTION: A pressure-sensitive adhesive contains a polyurethane resin (A) having a hydroxyl group, a reactive compound (B) having a functional group reactive with a hydroxyl group, and an ester compound (C), where the polyurethane resin (A) is a reaction product of polyol (a1) containing polyol (a1-1) having a surface tension of 20 mN/cm or more and less than 40 mN/cm and a number average molecular weight of 2,000 to 10,000 and polyol (a1-2) having a surface tension of 40 mN/cm or more and less than 60 mN/cm and a number average molecular weight of 400 to 4,000 and polyisocyanate (a2), and the number average molecular weight of the polyol (a1-1) is a number average molecular weight equal to or more than the number average molecular weight of the polyol (a1-2).SELECTED DRAWING: None

Description

  The present invention relates to a pressure-sensitive adhesive, an adhesive film using the same, and an optical laminate.

  Display devices such as liquid crystal displays used in various devices such as home and commercial appliances such as electronic calculators, electronic watches, mobile phones, and televisions are becoming larger, especially liquid crystal televisions and plasma televisions. The increase in size is remarkable. In recent years, touch panel type liquid crystal displays such as smartphones and tablets are rapidly spreading, and a large market expansion is expected in the future. On the other hand, liquid crystal displays are also used in in-vehicle devices such as car navigation systems, and are required to have durability that can be used in harsh interior environments such as high-temperature and high-humidity atmospheres.

Conventionally, a surface protective film is generally attached to an exposed surface side of an optical member such as a liquid crystal display in order to prevent surface contamination and scratches during processing, assembly, inspection, transportation, and the like. In particular, since the surface protection film for optical members may be repeatedly applied and peeled off during the manufacturing process, the surface of the optical member is contaminated during ease of sticking (wetting and spreading to the adherend) and peeling. Re-peelability (also called reworkability) is not required. In addition, as the optical member becomes thinner, the optical member itself becomes easier to break, and the surface protection film needs to have an adhesive property but can be peeled with a weaker force (light release property). It is coming. Furthermore, the surface protection film is required to have high durability that does not foam or peel off from the adherend even when exposed to heat and wet heat.
The laminated body such as an optical member to which this surface protective film is attached not only can be easily peeled off, but also prevents foaming, floating and peeling even under harsh environments such as high temperature or high temperature and high humidity conditions. Therefore, pressure sensitive adhesives containing acrylic resins and pressure sensitive adhesives containing silicone resins have been used.
However, pressure-sensitive adhesives containing acrylic resins may have a significant increase in adhesive strength over time after application due to insufficient cohesive strength of the adhesive layer itself, or adhesive residue may occur during peeling. There is a problem in using it as a surface protective film for a member that dislikes mixing of foreign matters such as an optical member and an electronic member.
In addition, the adhesive layer of the silicone resin tends to contaminate the adherend after peeling, and there is a problem in using it as a surface protective film for members that require particularly low contamination such as optical members and electronic members. It was.

  Then, the pressure sensitive adhesive containing the polyurethane resin which uses polyether polyol as a polyol unit is disclosed as a pressure sensitive adhesive which does not use an acrylic resin or a silicone resin (patent document 1 or 2). However, since the conventional pressure-sensitive adhesive of Patent Document 1 or 2 uses a polyurethane resin, flexibility is obtained and the adhesive force is improved, but the cohesive force is reduced and the adhesive remains easily. was there.

  In addition, a pressure-sensitive adhesive containing a polyurethane resin in which polyether polyol and polyester polyol are used in combination as a polyol unit is disclosed (Patent Document 3). However, an adhesive film using a polyurethane resin using a polyester polyol as a polyol unit has high cohesive force and can suppress adhesive residue, but the elastic modulus of the adhesive layer itself is also high and adhesion to the substrate is increased. There was a problem that it was lowered and sufficient adhesive strength could not be maintained.

For this improvement, a pressure-sensitive adhesive containing a carboxylic acid ester (Patent Document 4) or a polyether polyol or polyester polyol as a polyol unit is used for a polyurethane resin in which polyether polyol and polyester polyol are used in combination as a polyol unit. A pressure-sensitive adhesive (Patent Document 5) is disclosed in which the polyurethane resin contains a plastic resin such as a polyalkylene glycol compound, an epoxy compound, or a phosphate ester compound.
However, the pressure-sensitive adhesive of Patent Document 4 or 5 can increase the flexibility by containing a plastic resin in the polyurethane resin, but the cohesive force becomes poor. In addition to the deterioration of workability such as the sticking out and stickiness of the pressure adhesive, there was a problem that the removability was poor.

  Polyurethane resin originally has high hydrogen bonding properties, so it is easy to entrain air (also referred to as bubble scissors). Once air is entrained, it is difficult to remove bubbles. In many cases, a coating film defect was developed and the quality was deteriorated. For this improvement, when pressure sensitive adhesives using polyurethane resin are used, they can be left standing for a long time to remove bubbles during pressure sensitive adhesive production or coating, or bubbles can be removed under reduced pressure. There was also a potential problem that caused a drop in productivity.

  Also, the adhesive film using polyurethane resin, when the adhesive layers touch each other, unlike the acrylic resin, it adheres quite firmly (also called self-adhesion), so when the adhesive film that has been attached is peeled off The surface roughness of the adhesive layer becomes remarkable and the smoothness is impaired. The peeled adhesive film cannot be reused, and the workability is often lowered.

  In view of this situation, the productivity of pressure-sensitive adhesives and adhesive films is improved, self-adhesion of adhesive films is reduced, and durability such as heat resistance and moist heat resistance, wetting spreadability, and removability Therefore, a pressure-sensitive adhesive that can be used from a film label application to an electrical and optical application and can be used for a surface protection film has been desired.

JP 2006-18295 A JP 2014-028876 A Japanese Patent Laid-Open No. 2002-501954 JP, 2015-151429, A Japanese Patent Laying-Open No. 2015-007226

  The problem to be solved by the present invention is to improve the processability during the production of an adhesive film (prevention of sticking out and stickiness of the pressure-sensitive adhesive, improvement of bubble removal, reduction of bubble dust) in order to solve the above problems, A pressure-sensitive adhesive that has excellent removability when used in an adhesive film and is less likely to lift or peel off from the adherend after being exposed to a high-temperature environment or high-temperature and high-humidity environment. An object is to provide an adhesive film. Furthermore, when used as a surface protection film, it has good wettability, maintains high transparency even when exposed to high-temperature and high-humidity environments, and has good adhesive force even in a slightly viscous region. An object of the present invention is to provide a pressure-sensitive adhesive that does not contaminate an adherend such as a glass plate during peeling, and an adhesive film using the pressure-sensitive adhesive.

  As a result of intensive studies to solve the above problems, the present inventors have found that the object can be achieved by the pressure-sensitive adhesive shown below, and have completed the present invention.

  That is, an embodiment of the present invention is a pressure-sensitive adhesive comprising a polyurethane resin having a hydroxyl group (A), a reactive compound (B) having a functional group capable of reacting with a hydroxyl group, and an ester compound (C), The polyurethane resin (A) is a polyol (a1-1) having a surface tension of 20 mN / cm or more and less than 40 mN / cm and a number average molecular weight of 2,000 to 10,000, and a surface tension of 40 mN / cm or more and less than 60 mN / cm. The number average molecular weight of the polyol (a1-1) is a reaction product of a polyol (a1) containing a polyol (a1-2) having a number average molecular weight of 400 to 4,000 and a polyisocyanate (a2). Is a pressure-sensitive adhesive having a number average molecular weight equal to or higher than the number average molecular weight of the polyol (a1-2).

  Moreover, the embodiment of the present invention is the pressure-sensitive adhesive containing 50 to 99% by weight of polyol (a1-1) and 1 to 50% by weight of polyol (a1-2) in 100% by weight of polyol (a1). .

  Moreover, the embodiment of the present invention is the above-mentioned sensation comprising 0.1 to 50 parts by mass of the reactive compound (B) having a functional group capable of reacting with a hydroxyl group with respect to 100 parts by mass of the polyurethane resin (A) having a hydroxyl group. Pressure adhesive.

  Moreover, the embodiment of this invention is the said pressure sensitive adhesive which contains 1-100 mass parts of ester compounds (C) with respect to 100 mass parts of polyurethane resins (A) which have a hydroxyl group.

  An embodiment of the present invention is the pressure-sensitive adhesive, wherein the polyurethane resin (A) has a weight average molecular weight of 10,000 to 500,000.

  An embodiment of the present invention is the pressure-sensitive adhesive described above, wherein the polyol (a1) contains a polyol having 3 or more hydroxyl groups.

  Moreover, the embodiment of this invention is a pressure sensitive adhesive of any one of Claims 1-6 in which the reactive compound (B) contains polyisocyanate (b1).

  An embodiment of the present invention is the pressure-sensitive adhesive, wherein the ester compound (C) has a surface tension of 20 mN / cm or more and less than 40 mN / cm.

  Furthermore, an embodiment of the present invention is the pressure-sensitive adhesive further including an ionic compound (D).

  Moreover, the embodiment of this invention is a pressure sensitive adhesive film provided with the base material (G) and the contact bonding layer which is the hardened | cured material of the said pressure sensitive adhesive.

  An embodiment of the present invention is an optical laminate including the optical film (I), an adhesive layer that is a cured product of the pressure-sensitive adhesive, and glass.

  By using the pressure-sensitive adhesive of the present invention, it is possible to overcome defects (such as coating film defects due to bubble burrs and reduction of self-adhesiveness) caused by troubles during coating, adhesion to the substrate, and removability. A pressure-sensitive adhesive that can form a pressure-sensitive adhesive layer excellent in heat resistance, moist heat resistance and transparency and can be suitably used for bonding for optical members is provided. Furthermore, the use of the pressure-sensitive adhesive does not cause foaming or peeling even at high temperatures or high humidity, and it also provides excellent prevention of dirt and scratches on the surface of optical members during processing, assembly, inspection, transportation, etc. Thus, a surface protective film that does not contaminate the adherend during peeling can be provided.

Hereinafter, embodiments of the present invention will be described.
The pressure-sensitive adhesive of the present invention comprises 0.1 to 50 parts by mass of a reactive compound (B) having a functional group capable of reacting with a hydroxyl group and 100 parts by mass of the ester compound (C) 1 with respect to 100 parts by mass of the polyurethane resin (A). It is a pressure-sensitive adhesive containing ˜100 parts by mass. The pressure-sensitive adhesive of the present invention is preferably used as an adhesive film in which an adhesive layer formed by coating on a substrate is laminated.
Hereinafter, the components of the pressure-sensitive adhesive will be specifically described.

<Polyurethane resin (A)>
The polyurethane resin (A) is a resin containing a polyol (a1) unit and a polyisocyanate (a2) unit as monomer units constituting it, and is a resin produced by polymerizing these monomer mixtures.

<< Polyol (a1) >>
First, the polyol (a1) unit, which is a monomer unit constituting the polyurethane resin (A), will be described.
The polyol (a1) referred to in this specification is a polyol (a1-1) having a surface tension of 20 mN / cm or more and less than 40 mN / cm, and a polyol (a1-) having a surface tension of 40 mN / cm or more and less than 60 mN / cm. 2).

Since the polyol (a1) contains the polyol (a1-1) having a surface tension of 20 mN / cm or more and less than 40 mN / cm, the polyol (a1) has a low-polarity part, so that air that is involved in the production of the pressure sensitive adhesive is easily removed As well as reducing the air entrainment of the coater head (also known as bubble burrs) that occurs during the application of adhesive film, it can suppress coating film defects on the adhesive film and produce It leads to improvement of sex. In addition, since compatibility with the ester compound (C) described later is improved and migration can be suppressed, flexibility can be maintained over a long period of time, tack (adhesiveness) can be reduced, and wettability can be improved. .
In addition, since it contains a polyol (a1-2) having a surface tension of 40 mN / cm or more and less than 60 mN / cm, it has a highly polar part, so it foams, floats and peels even under harsh environments such as high temperature and high humidity conditions. In addition, since the compatibility with the ester compound (C) described later is low, the adhesive force of the pressure-sensitive adhesive to the glass plate can be re-peeled because the compatibility with the ester compound (C) described later is low. It becomes possible to reduce to a slightly viscous region (for example, an adhesive force of less than 10.0 mN / 25 mm).

Thus, the polyol (a1-1) having a surface tension of 20 mN / cm or more and less than 40 mN / cm (hereinafter also referred to as low-polar polyols) and the surface tension of 40 mN / cm or more and less than 60 mN / cm. The pressure-sensitive adhesive using the polyurethane resin (A) obtained by an appropriate balance of the polyol (a1-2) (hereinafter sometimes referred to as high polar polyols) is difficult to entrain air, and the entrained air is Even if it is generated as a foam, it is quickly eliminated and the productivity is improved. Further, the adhesive layer of the produced adhesive film forms a micro phase separation structure, and the surface of the adhesive layer is formed with minute irregularities so that air entrainment can be suppressed and further includes an ester compound (C) described later. It is possible to obtain a stable wetting and spreading property while maintaining flexibility from room temperature to low temperature.
Further, by containing a trifunctional or higher functional polyol having 3 or more hydroxyl groups, it is possible to introduce a hydroxyl group that can be a crosslinking point with the reactive compound (B) described later into the polyurethane resin (A). Therefore, it is possible to control the balance between the removability and the adhesiveness and wettability of the slightly viscous region.

  Examples of such polyol (a1) include short-chain polyols, polyether polyols, polyester polyols, polyamide polyols, polycarbonate polyols, polyols having a diene skeleton, polyols having a siloxane skeleton, and ionic functional groups. And the like containing polyols.

The short-chain polyols are compounds that can be a monomer that becomes a minimum unit constituting other polyols having a repeating unit having a polymerization degree of 2 or more described later.
Examples of the short chain polyols include propylene glycol, dipropylene glycol, 2-methyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,3-butanediol, 1 , 4-butanediol, 1,5-pentanediol, 3-butyl-3-ethyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentane Diol, neopentyl glycol, 1,6-hexanediol, 2-ethyl-1,3-hexanediol, 3,3′-dimethylolheptane, 1,8-octanediol, 2-methyl-1,8-octanediol 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,12-octadecanediol, Linear low-polar aliphatic diols such as 1,4-tetracosanediol, 1,6-tetracosanediol, 1,4-hexacosanediol, 1,6-octacosanediol;

  For example, chain-like highly polar aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,3-propanediol;

  For example, 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, tricyclodecane diethanol, cyclopentadiene dimethanol, 2,5-norbornanediol, 1,3-adamantanediol, etc. Polar alicyclic diols;

  For example, alicyclic diols having low polarity such as 2,2,4,4, -tetramethyl-1,3-cyclobutanediol, dimer diol;

  For example, o-, m-, and p-dihydroxybenzene, 1,2-indanediol, benzene-1,2-dimethanol (also known as phthalyl alcohol), benzene-1,3-dimethanol (also known as isophthalyl) Alcohol), benzene-1,4-dimethanol (also known as terephthalyl alcohol), 1,3-bis (2-hydroxyethoxy) benzene, 1,2-bis (2-hydroxyethoxy) benzene, 1,4-bis (2-hydroxyethoxy) benzene, (3,4-dihydroxyphenyl) methanol (alias: protocatechuyl alcohol), (4-hydroxy-3-methoxyphenyl) methanol (alias: vanillyl alcohol), 2- (4- Hydroxy-3-methoxyphenyl) ethane-1-ol (also known as homovanillyl alcohol), 3 (4-hydroxy-3-methoxyphenyl) prop-2-en-1-ol (also known as coniferyl alcohol), 3- (4-hydroxy-3,5-dimethoxyphenyl) prop-2-en-1-ol (Alternative name: Synapyl alcohol), 1,2-diphenylethane-1,2-diol (Alternative name: hydrobenzoin), hydroquinone, resorcin, 4-chlororesorcin, 4-methylresorcin, 5-methylbenzene-1,3- Diol (alias: orcinol), 2-methylbenzene-1,4-diol (alias: tolhydroquinone), 2,3-dimethylbenzene-1,4-diol (alias: o-xylohydroquinone), 2,6-dimethyl Benzene-1,4-diol (also known as m-xylohydroquinone), 2,5-dimethylbenzene-1,4-di (Aka p-xylohydroquinone), 2,3,5-trimethylbenzene-1,4-diol (aka pseudo spider hydroquinone), 2-isopropyl-5-methylbenzene-1,4-diol (alias) : Thymohydroquinone), 2,3,5,6-tetramethylbenzene-1,4-diol (alias: jurohydroquinone), 5-pentylbenzene-1,3-diol (alias: olivetol), 4,4′- Methylene diphenol (alias: pp-bisphenol F), 4,4 ′-(2-norbornylidene) diphenol, 4,4′-dihydroxymethylbiphenyl, 4,4′-biphenyldiol, 2,3-dihydroxybutenyl, Tetranitrobiphenyldiol, 5,5′-dipropyl-biphenyl-2,2′-diol, 3,3′-diamy Nobiphenyl-4,4′-diol, 5,5′-tetramethylbiphenyl-4,4′-diol, diphenylsilanediol, (E) -4,4 ′-(hex-3-ene-3,4- Diyl) diphenol (also known as diethylstilbestrol), 2,2-bis (4-hydroxyphenyl) sulfone (also known as bisphenol S), 4,4'-isopropylidenephenol, 4,4'-dihydroxydiphenyl ether : 4,4'-oxydiphenol), 2,2-bis (4-hydroxyphenyl) propane (also known as bisphenol A), 1,3-naphthalenediol, 1,5-naphthalenediol, 1,7-naphthalenediol 1,7-dihydroxymethylnaphthalene, ammonium 1,4-dihydroxy-2-naphthalenesulfonate, 9 , 9′-bis (4-hydroxyphenyl) fluorene, 9,9′-bis (3-methyl-4-hydroxyphenyl) fluorene 1,4-dihydro-9,10-anthracenediol, etc. Diols;

  For example, glycerin, 1,1,1-trimethylolpropane, 1,1,1-trimethylolbutane, 1,1,1-trimethylolpentane, 1,1,1-trimethylolhexane, 1,1,1- Trimethylol heptane, 1,1,1-trimethylol octane, 1,1,1-trimethylol nonane, 1,1,1-trimethylol decane, 1,1,1-trimethylol undecane, 1,1,1- Trimethylol-sec-butane, 1,1,1-trimethylol-tert-pentane, 1,1,1-trimethylol-tert-nonane, 1,1,1-trimethylol-tert-tridecane, 1,1, 1-trimethylol-tert-heptadecane, 1,1,1-trimethylol-2-methyl-hexane, 1,1,1-trimethylol-3-methyl -Hexane, 1,1,1-trimethylol-2-ethyl-hexane, 1,1,1-trimethylol-3-ethyl-hexane, 1,1,1-trimethylolisoheptadecane, trimethylolbutene, tri Methylol heptene, trimethylol pentene, trimethylol hexene, trimethylol heptene, trimethylol octene, trimethylol decene, trimethylol dodecene, trimethylol tridecene, trimethylol pentadecene, trimethylol hexadecene, trimethylol heptadecene, tri Methylol octadecene, 1,2,3-butanetriol, 1,2,4-butanetriol, 1,2,3-octanetriol, 1,3,7-octanetriol, 3,7-dimethyl-1,2, 3-octanetriol, 1,2, 0-dencantriol, 1,2,3,4-butanetetraol, pentaerythritol, dipentaerythritol, tripentaerythritol, diglycerin, triglycerin, polyglycerin, ditrimethylolethane, ditrimethylolpropane, tris (2- Hydroxyethyl) isocyanurate, benzene-1,3,5-triol (also known as phloroglicinol), benzene-1,2,3-triol (also known as pyrogallol), stilbene-3,4 ', 5-triol (also known as : Resveratrol), inositol, sorbitan, sorbitol, mannitol, saccharose, cellulose and other highly polar polyols having three or more hydroxyl groups;

  For example, 1,1,1-trimethylol dodecane, 1,1,1-trimethylol tridecane, 1,1,1-trimethylol tetradecane, 1,1,1-trimethylol pentadecane, 1,1,1-tri Methylol hexadecane, 1,1,1-trimethylol heptadecane, 1,1,1-trimethylol octadecane, 1,1,1-trimethylol nonadecane, 1,1,2-tetradecane triol, 1,2,3- Examples thereof include low-polarity polyols having three or more hydroxyl groups such as octadecane triol.

Here, the dimer diol is a carboxylic acid having 18 carbon atoms such as an unsaturated fatty acid such as linoleic acid, oleic acid or linolenic acid, a dry oil fatty acid or a semi-dry oil fatty acid obtained from tall oil, cottonseed oil, soybean oil or the like. Is an aliphatic diol having 36 carbon atoms obtained by further complete hydrogenation of the dimer acid obtained by thermal polymerization of the dimer acid, and is obtained as a mixture of dimer diol geometric isomers having a branched structure and a cyclohexane ring. Compound. Examples of commercially available products include PRIPOL-2030 and 2033 (manufactured by CRODA Coating & Polymers) and Sovermol-908 (manufactured by BASF).
The term “chain aliphatic” as used herein means an acyclic chain carbon compound, and the cyclic carbon compound is defined as alicyclic.

  Moreover, 50-800 are preferable and, as for the formula weight (Mn and a number average molecular weight) of short chain polyols, 60-600 are more preferable. When the formula amount (Mn) is within this range, the pseudo-crystallinity of the later-described polyether polyol, polyester polyol, polyamide polyol, or polycarbonate polyol is destroyed, so that the viscosity of the polyurethane resin can be reduced and the coating processability is good. Become. Moreover, since flexibility becomes higher, it becomes easy to express adhesiveness. For the formula weight (Mn), literature values described in Chemical Handbook, Basic Edition, Rev. 5 (2004, The Chemical Society of Japan) etc. were used.

  Among these, highly polar aliphatic diols, highly polar aromatic diols, or highly polar having three or more hydroxyl groups are highly polar in terms of compatibility with the ester compound (C) described later. It is preferable to have a certain polyol, but in order to reduce the tack (tackiness) of the pressure-sensitive adhesive and to control the adhesiveness in the microviscous region, the above-described low-polarity alicyclic diols, low Low polar diols such as polar alicyclic diols or low polarity polyols having three or more hydroxyl groups may be contained. By using together with polyols other than the short-chain polyol described later, it is possible to add a point of reducing tack (adhesiveness) to the polyurethane resin (A) and a point capable of imparting flexibility accompanying density reduction.

  Known polyether polyols can be used as the polyether polyols. Polyether polyols are polyoxyalkylene polyols obtained by ring-opening addition polymerization of alkylene oxide to an initiator having 2 to 4 active hydrogen atoms. Examples of the initiator include the above short-chain polyols and aliphatic amines (for example, alkylenediamines such as ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, and neopentyldiamine, alkanolamines such as monoethanolamine and diethanolamine). In consideration of the wettability of the pressure-sensitive adhesive to the base material, it is particularly preferable to use the short-chain polyol as an initiator to obtain a polyether polyol. These may be used alone or in combination of two or more.

Examples of the alkylene oxide include those having a polyoxyalkylene skeleton by ring-opening addition polymerization of ethylene oxide, propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, oxetane, tetrahydrofuran and the like.
Examples of the polyether polyol having an alkylene oxide skeleton include polyethylene glycol, polyethylene propylene glycol (ethylene oxide / propylene oxide copolymer) having a surface tension of 40 mN / cm or more, and polyethylene tetramethylene glycol (copolymer of ethylene oxide / tetramethylene oxide). Polymer), addition of ethylene oxide to bisphenols such as bisphenol A and bisphenol F, which are ring-opening polymerized ethylene oxide using diols described in the above short-chain polyol as an initiator. Highly polar polyether diols such as aryl polyethylene glycol having an aromatic ring

  For example, polypropylene glycol, polytrimethylene glycol, polytetramethylene glycol, polypentamethylene glycol, polyhexamethylene glycol, polyoctamethylene glycol, polyethylene propylene glycol (ethylene oxide / propylene oxide copolymer) having a surface tension of less than 40 mN / cm ), Polyethylene tetramethylene glycol (ethylene oxide / tetramethylene oxide copolymer), alkyl polypropylene glycol, cycloalkyl polypropylene glycol, or bisphenol obtained by ring-opening polymerization of propylene oxide using the diol described in the above short-chain polyol as an initiator. A with an aromatic ring formed by adding propylene oxide to bisphenols such as A and bisphenol F Lumpur polypropylene glycol low polarity polyether diols such as and the like.

  For example, polyethylene triols such as polyoxyethylene glycerin and polyoxyethylene trimethylolpropane, polyoxyalkylene triols such as polyoxyethylene polyoxypropylene trimethylolpropane having a surface tension of 40 mN / cm or more, polyethylene such as polyoxyethylene pentaerythritol Highly polar polyhydric polyols having 3 or more hydroxyl groups having 2 to 45 hydroxyl groups added: ethylene oxide (EO) such as tetraol and polyoxyethylene polyol such as polyoxyethylene sorbit;

  For example, polypropylene triols such as polyoxypropylene glycerin and polyoxypropylene trimethylolpropane, polyoxyethylene polyoxypropylene trimethylolpropane having a surface tension of less than 40 mN / cm, polypropylene tetraols such as polyoxypropylene pentaerythritol, and polyoxy Examples include low-polarity polyhydric polyols having 3 or more hydroxyl groups having 2 to 45 added moles of propylene oxide (PO) such as propylene sorbite polyoxyethylene polyvalent ol.

  Among these, the above highly polar polyether diols and the highly polar polyhydric polyols having 3 or more hydroxyl groups are highly polar polyols having a surface tension of 40 mN / cm or more and less than 60 mN / cm. (A1-2) belonging to (a1-2), the above-mentioned low-polar polyether diols and high-polarity polyhydric polyols having 3 or more hydroxyl groups are low-polarity polyols, and the surface tension is 20 mN / cm or more and 40 mN / cm. It belongs to the polyol (a1-1) which is less than.

Among these, when a polyether polyol having a low-polarity alkylene oxide skeleton is used, when used as a pressure-sensitive adhesive, not only does it exhibit good defoaming properties during production, but the produced adhesive film has good heat resistance. Durability, such as heat resistance and wet heat resistance, can be improved, and tack (adhesiveness) can be reduced.
For example, polypropylene glycol is particularly preferable from the viewpoint of compatibility between the adhesiveness of the slightly viscous region and the wettability. Further, it is preferable to use polyhydric polyols having three or more hydroxyl groups that can introduce a hydroxyl group that can be a crosslinking point with the reactive compound (B) described later and that can further control the cohesive force. Polypropylene triols such as oxypropylene glycerin and polyoxypropylene trimethylolpropane, and polyoxyalkylene triols such as polyoxyethylene polyoxypropylene trimethylolpropane having a surface tension of less than 40 mN / cm are preferably used in combination. Use in low-polarity polyhydric polyols with 3 or more hydroxyl groups to control adhesiveness in the microviscous region and achieve both high level of removability and wettability. It becomes possible to do. In addition, it becomes difficult to entrain air during the production of the pressure-sensitive adhesive or during coating, and the bubble removal is improved, so that it is possible to suppress the occurrence of coating film defects.

  As the polyether polyol, a commercially available product can be used. For example, PEG400 (Mn = 400, hydroxyl value = 275, acid value <0.5, linear liquid type), PEG600 (Mn = 600, hydroxyl value = 180, Acid value <0.5, linear liquid type), PEG1000 (Mn = 1,000, hydroxyl value = 112, acid value <0.5, linear waxy type), PEG2000 (Mn = 2,000, hydroxyl value = 56) , Acid value <0.5, linear wax type), PEG 4000N (Mn = 3,000, hydroxyl value = 37, acid value <0.5, linear wax type), PEG 10000 (Mn = 10,000, hydroxyl value) = 11, acid value <0.5, linear solid type), Newpol PP-400 (Mn = 400, hydroxyl value = 275, acid value <0.5, linear liquid type), new Pole PP-1000 (Mn = 1,000, hydroxyl value = 112, acid value <0.5, linear liquid type), New Pole PP-2000 (Mn = 2,000, hydroxyl value = 56, acid value <0. 5, linear liquid type), Newpol PP-4000 (Mn = 4,000, hydroxyl value = 28, acid value <0.5, linear liquid type), Newpol GP-1000 (Mn = 1,000, hydroxyl value) = 112, acid value <0.5, linear liquid trifunctional type), New Pole GP-4000 (Mn = 4,000, hydroxyl value = 28, acid value <0.5, linear liquid trifunctional type), prime pole FF-3550 (Mn = 5,000, hydroxyl value = 34, acid value <0.5, linear liquid trifunctional type), Primepole FF-3320 (Mn = 3,000, hydroxyl value = 56, acid value <0) .5 Linear Tripole type), Primepole FH-2200 (Mn = 2,000, hydroxyl value = 56, acid value <0.5, linear liquid type), Primepole PX-1000 (Mn = 1,000, hydroxyl value = 115, acid value <0.5, linear liquid type) [above, manufactured by Sanyo Chemical Industries Ltd.];

  ADEKA polyether P-1000 (Mn = 1,000, hydroxyl value = 110, acid value <0.1, linear liquid type), ADEKA polyether P-2000 (Mn = 2,000, hydroxyl value = 56, acid value) <0.1, linear liquid type), ADEKA polyether G-1500 (Mn = 1,500, hydroxyl value = 110, acid value <0.1, linear liquid trifunctional type), ADEKA polyether G-3000B (Mn = 3,000, hydroxyl value = 56, acid value <0.1, linear liquid trifunctional type), ADEKA polyether AM-302 (Mn = 3,000, hydroxyl value = 56, acid value <0.1, linear) Liquid trifunctional type), ADEKA polyether AM-502 (Mn = 4,600, hydroxyl value = 36, acid value <0.1, linear liquid trifunctional type), ADEKA polyether GR-2505 (Mn = 2,50) , Hydroxyl value = 69, acid value <0.1, linear liquid trifunctional type), ADEKA polyether GR-3308 (Mn = 3,400, hydroxyl value = 25, acid value <0.1, linear liquid trifunctional type) [The above, made by Adeka Corporation];

  EXCENOL 420 (Mn = 400, hydroxyl value = 280, acid value <0.03, linear liquid type), EXCENOL 1020 (Mn = 1,000, hydroxyl value = 112, acid value <0.05, linear liquid type), EXCENOL 2020 (Mn = 2,000, hydroxyl value = 56, acid value <0.05, linear liquid type), EXCENOL 3020 (Mn = 3,000, hydroxyl value = 35, acid value <0.03, linear liquid type) ), EXCENOL 510 (Mn = 4,000, hydroxyl value = 28, acid value <0.05, linear liquid type), EXCENOL 1030 (Mn = 1,000, hydroxyl value = 160, acid value <0.05, linear) Liquid trifunctional type), EXCENOL 240 (Mn = 3,000, hydroxyl value = 56, acid value <0.05, linear liquid trifunctional type), EXCEN OL 820 (Mn = 4,900, hydroxyl value = 34, acid value <0.05, linear liquid trifunctional type), EXCENOL 823 (Mn = 5,100, hydroxyl value = 33, acid value <0.05, linear Liquid trifunctional type) [above, manufactured by Asahi Glass]

  PTG 1000 (Mn = 1,000, hydroxyl value = 110, acid value <0.05, linear wax type), PTG 2000 (Mn = 2,000, hydroxyl value = 56, acid value <0.05, linear wax) ), PTG 3000 (Mn = 3,000, hydroxyl value = 36, acid value <0.05, linear wax type) [above, manufactured by Hodogaya Chemical Co., Ltd.];

  PTMG1000 (Mn = 1,000, hydroxyl value = 110, acid value <0.05, linear wax type), PTMG 2000 (Mn = 2,000, hydroxyl value = 56, acid value <0.05, linear wax type) Type) [Mitsubishi Chemical Corporation];

  BLAUNON GL-9 (Mn = 650, hydroxyl value = 259, acid value <0.05, linear liquid trifunctional type), BLAUNON GL-20 (Mn = 1,300, hydroxyl value = 127, acid value <0.05) , Linear liquid trifunctional type), BLAUNON GL-26 (Mn = 1,700, hydroxyl value = 100, acid value <0.05, linear liquid trifunctional type) [above, manufactured by Aoki Yushi Kogyo Co., Ltd.];

  UNIOX G-450 (Mn = 450, hydroxyl value = 374, acid value <0.05, linear liquid trifunctional type), UNIOX G-750 (Mn = 750, hydroxyl value = 224, acid value <0.05) , Linear liquid trifunctional type), Uniol TG1000 (Mn = 1,000, hydroxyl value = 110, acid value <0.05, linear liquid trifunctional type), Uniol TG2000 (Mn = 2,000, hydroxyl value = 84, Acid value <0.05, linear liquid trifunctional type), Uniol TG3000 (Mn = 3,000, hydroxyl value = 56, acid value <0.05, linear liquid trifunctional type), TG4000 (Mn = 4,000, Hydroxyl value = 42, acid value <0.05, linear liquid trifunctional type) [above, manufactured by NOF Corporation];

    HQ-20 (Mn = 200, hydroxyl value = 565, acid value <0.1, aromatic solid containing linear solid type), BA-4 glycol (Mn = 400, hydroxyl value = 280, acid value <0.1, Aromatic ring-containing linear liquid type), BA-6 glycol (Mn = 500, hydroxyl value = 225, acid value <0.1, aromatic ring-containing linear liquid type), BA-10 glycol (Mn = 660, hydroxyl value = 170). , Acid value <0.1, aromatic ring-containing linear liquid type), BA-17 glycol (Mn = 950, hydroxyl value = 170, acid value <0.1, aromatic ring-containing linear liquid type), BA-P4 glycol ( Mn = 450, hydroxyl value = 250, acid value <0.1, aromatic ring-containing linear liquid type), BA-P8 glycol (Mn = 660, hydroxyl value = 170, acid value <0.5, aromatic ring-containing linear liquid) Type), BPF4 Mn = 380, hydroxyl value = 300, acid number <0.1, the aromatic ring-containing linear liquid type) [above, Nippon Emulsifier Co. Ltd.] and the like can be given.

Polyester polyols can be obtained by the condensation reaction of the above short-chain polyols and polycarboxylic acids, and most polyester polyols have a surface tension of 40 mN / cm or more. Therefore, high-polarity polyols (a1-2) Belonging to.
Known polycarboxylic acids used for obtaining polyester polyols include, for example, oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, suberic acid, maleic acid, chloromaleic acid, fumaric acid, and dodecane. Aliphatic dicarboxylic acids such as diacid, pimelic acid, citraconic acid, glutaric acid, itaconic acid, succinic anhydride, maleic anhydride, and anhydrides thereof;

  Examples thereof include alicyclic dicarboxylic acids such as dimer acid, hexahydroterephthalic acid, hexahydroisophthalic acid, hexahydrophthalic acid and tetrahydrophthalic acid, and anhydrides thereof.

  For example, o-phthalic acid, isophthalic acid, terephthalic acid, 2,5-dimethylterephthalic acid, 4,4-biphenyldicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, norbornene dicarboxylic acid, diphenylmethane Aromatic dicarboxylic acids such as -4,4'-dicarboxylic acid, phenylindanedicarboxylic acid and phthalic anhydride, and anhydrides thereof;

  For example, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, 4-methylcyclohexane-1,2,3-tricarboxylic acid, (1a, 2a, 4a) -1,2,4-cyclohexanetricarboxylic acid Acid, 1,2,3,4-butanetetracarboxylic acid, 1,2,3,4-pentanetetracarboxylic acid, cyclopentanetetracarboxylic acid, ethylenetetracarboxylic acid, 4-methylcyclohexene-1,2,3- Tricarboxylic acid, trimesic acid, 1,2,3,4-butanetetracarboxylic acid, 1,2,3,4-pentanetetracarboxylic acid, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid, cyclopentanetetra Carboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, ethylene A tri- or higher functional polycarboxylic acid such as glycol bistrimellitate carboxylic acid, 2,2 ′, 3,3′-diphenyltetracarboxylic acid, thiophene-2,3,4,5-tetracarboxylic acid, ethylenetetracarboxylic acid, and the like; Its anhydrides, etc .;

In addition, polyester polyols obtained by ring-opening polymerization of lactones such as polycaprolactone, poly (β-methyl-γ-valerolactone), and polyvalerolactone can also be used.
In this way, by using polyester polyol, because it is highly polar, it can maintain durability without foaming, floating and peeling even under harsh environments such as high-temperature and high-humidity conditions. Since the compatibility with the compound (C) is low, it is oriented on the adhesive surface of the adhesive film, and tack (tackiness) can be reduced over a long period of time. In consideration of reducing the adhesive strength of pressure-sensitive adhesives to adherends such as glass plates to a removable microviscous region, the above aliphatic or alicyclic dicarboxylic acids and their anhydrides are used. It is preferable to use an aliphatic or alicyclic polyester polyol in combination. These may be used alone or in combination of two or more.

  As the polyester polyols, commercially available products can be used. For example, Kuraray polyol P510 (Mn = 500, hydroxyl value = 224, acid value <0.5, linear liquid type), Kuraray polyol P1010 (Mn = 1,000, Hydroxyl value = 112, acid value <0.5, linear liquid type), Kuraray polyol P2010 (Mn = 2,000, hydroxyl value = 56, acid value <0.5, linear liquid type), Kuraray polyol P3010 (Mn = 3,000, hydroxyl value = 37, acid value <0.5, linear liquid type), Kuraray polyol P4010 (Mn = 4,000, hydroxyl value = 28, acid value <0.5, linear liquid type), Kuraray polyol P5010 (Mn = 5,000, hydroxyl value = 22, acid value <0.5, linear liquid type), Kuraray polyol P6010 (Mn = 6,000) , Hydroxyl value = 19, acid value <0.5, linear liquid type), Kuraray polyol P2050 (Mn = 2,000, hydroxyl value = 56, acid value <0.5, linear liquid type), Kuraray polyol P3050 (Mn) = 3,000, hydroxyl value = 37, acid value <0.5, linear liquid type), Kuraray polyol P4050 (Mn = 4,000, hydroxyl value = 28, acid value <0.5, linear liquid type), Kuraray Polyol N2010 (Mn = 2,000, hydroxyl value = 56, acid value <0.5, linear liquid type), Kuraray polyol N4010 (Mn = 4,000, hydroxyl value = 28, acid value <0.5, linear liquid) Type), Kuraray polyol PNOA1010 (Mn = 1,000, hydroxyl value = 112, acid value <0.5, linear liquid type), Kuraray polyol PNOA2014 (Mn = 2) 000, hydroxyl value = 56, acid value <0.5, linear liquid type), Kuraray polyol P1012 (Mn = 1,000, hydroxyl value = 112, acid value <1, aromatic ring-containing linear liquid type), Kuraray polyol P2012 (Mn = 2,000, hydroxyl value = 56, acid value <1, aromatic ring-containing linear liquid type), Kuraray polyol P1013 (Mn = 1,000, hydroxyl value = 112, acid value <1, aromatic ring-containing linear liquid type) Type), Kuraray polyol P2013 (Mn = 2,000, hydroxyl value = 56, acid value <1, aromatic ring-containing linear liquid type), Kuraray polyol P1020 (Mn = 1,000, hydroxyl value = 112, acid value <1) , Aromatic ring-containing linear liquid type), Kuraray polyol P2020 (Mn = 2,000, hydroxyl value = 56, acid value <1, aromatic ring-containing linear liquid type), Repolyol P530 (Mn = 500, hydroxyl value = 224, acid value <0.5, aromatic liquid-containing linear liquid type), Kuraray polyol P1030 (Mn = 1,000, hydroxyl value = 112, acid value <0.5, Aromatic ring-containing linear liquid type), Kuraray polyol P2030 (Mn = 2,000, hydroxyl value = 56, acid value <0.5, aromatic ring-containing linear liquid type), Kuraray polyol F1010 (Mn = 1,000, hydroxyl value) = 168, acid value <0.5, linear liquid trifunctional type), Kuraray polyol F2010 (Mn = 2,000, hydroxyl value = 84, acid value <0.5, linear liquid trifunctional type), Kuraray polyol F3010 ( Mn = 3,000, hydroxyl value = 56, acid value <0.5, linear liquid trifunctional type) [above, manufactured by Kuraray Co., Ltd.];

  For example, URIC H-62 (Mn = 430, hydroxyl value = 260, acid value <4.0, linear liquid type), URIC Y-202 (Mn = 980, hydroxyl value = 115, acid value <1.0, linear) Liquid type), URIC Y-332 (Mn = 910, hydroxyl value = 123, acid value <1.0, linear liquid type), URIC SE-3506 (Mn = 3,500, hydroxyl value = 32, acid value <1) 0.0, white solid type), URIC H-52 (Mn = 840, hydroxyl value = 200, acid value <3.0, white solid trifunctional type), URIC AC-005 (Mn = 550, hydroxyl value = 205, acid value <4.0, aromatic ring-containing linear liquid type), URIC AC-006 (Mn = 650, hydroxyl value = 178, acid value <5.0, aromatic ring-containing linear liquid type) Made by company];

  For example, PLACEL 205 (Mn = 530, hydroxyl value = 212, acid value <1.0, linear liquid type), PLACEL 208 (Mn = 830, hydroxyl value = 135, acid value <1.0, linear wax type) PLACEL 210 (Mn = 1,000, hydroxyl value = 114, acid value <1.0, linear wax type), PLACEL 220 (Mn = 2,000, hydroxyl value = 56, acid value <1.0, linear) Wax type), PLACEL 230 (Mn = 3,000, hydroxyl value = 37, acid value <1.0, linear waxy type), PLACEL 240 (Mn = 4,000, hydroxyl value = 28, acid value <1. 0, linear waxy type), PLACEL 303 (Mn = 300, hydroxyl value = 540, acid value <1.5, linear liquid trifunctional type), PLAC CEL 305 (Mn = 550, hydroxyl value = 305, acid value <1.0, linear liquid trifunctional type), PLACEL 308 (Mn = 850, hydroxyl value = 195, acid value <1.5, linear liquid trifunctional type) ), PLACEL 309 (Mn = 950, hydroxyl value = 187, acid value <1.0, linear liquid trifunctional type), PLACEL 312 (Mn = 1,250, hydroxyl value = 135, acid value <1.0, white) Solid trifunctional type), PLACEL 320 (Mn = 2,000, hydroxyl value = 84, acid value <1.0, white solid trifunctional type), PLACEL 420 (Mn = 1,000, hydroxyl value = 224) Acid value <1.0, linear liquid tetrafunctional type) [above, manufactured by Daicel Corporation];

  For example, Kyowapol 2000BA (Mn = 2,000, hydroxyl value = 58, acid value <0.5, linear liquid type), Kyowapol 5000PA (Mn = 5,000, hydroxyl value = 22, acid value <0.5) , Linear liquid type) [above, manufactured by Kyowa Hakko Chemical Co., Ltd.];

  For example, polylite OD-X-221 (Mn = 2,000, hydroxyl value = 56, acid value <0.3, linear liquid type), polylite OD-X-2586 (Mn = 850, hydroxyl value = 200, acid value) = 0.4, linear liquid type), polylite OD-X-2420 (Mn = 2,000, hydroxyl value = 56, acid value = 0.4, linear liquid type), polylite OD-X-2523 (Mn = 3). , 500, hydroxyl value = 32, acid value = 0.5, linear solid type), polylite OD-X-2547 (Mn = 4,500, hydroxyl value = 25, acid value = 0.3, linear solid type), Polylite OD-X-102 (Mn = 2,000, hydroxyl value = 56, acid value = 1.3, linear solid type), Polylite OD-X-2420 (Mn = 2,000, hydroxyl value = 56, acid value) = 0.3, linear liquid Polylite OD-X-2155 (Mn = 1,000, hydroxyl value = 115, acid value = 0.2, linear solid type), Polylite OD-X-2722 (Mn = 2,000, hydroxyl value = 58) , Acid value = 0.3, linear liquid type) [above, manufactured by DIC Corporation];

  For example, NIPPOLAN 4002 (Mn = 1,000, hydroxyl value = 110, acid value <2, linear solid type), NIPPOLAN 4040 (Mn = 2,000, hydroxyl value = 56, acid value <2, linear solid type), NIPPOLAN 4009 (Mn = 1,000, hydroxyl value = 110, acid value <2, linear solid type), NIPPOLAN 4010 (Mn = 2,000, hydroxyl value = 56, acid value <2, linear solid type), NIPPOLAN 164 (Mn = 1,000, hydroxyl value = 110, acid value <1, linear solid type), NIPPOLAN 4073 (Mn = 2,000, hydroxyl value = 56, acid value <1, linear solid type), NIPPOLAN 152 (Mn = 1,000, hydroxyl value = 110, acid value <1, linear liquid type), NIPPOLAN 1004 (Mn = 2,600, hydroxyl value = 42, acid value <2, linear liquid type) Nippolan 5018 (Mn = 2,000, hydroxyl value = 56, acid number <1, the linear solid type) [above, Tosoh - made Company]

  For example, MAXMOL RDK-133 (Mn = 360, hydroxyl value = 315, acid value = 0.5, linear liquid type), MAXMOL RDK-142 (Mn = 280, hydroxyl value = 400, acid value = 0.5, linear) Liquid type) [above, manufactured by Kawasaki Kasei Kogyo Co., Ltd.];

  For example, Adeka New Ace NS2400 (Mn = 2,000, hydroxyl value = 56, acid value <0.3, linear liquid type), Adeka New Ace YT-101 (Mn = 680, hydroxyl value = 165, acid value <0) .3, linear liquid type), Adeka New Ace F7-67 (Mn = 2,000, hydroxyl value = 56, acid value <0.3, linear liquid type), Adeka New Ace YG-108 (Mn = 1,000) , Hydroxyl value = 120, acid value <0.3, linear solid type), Adeka New Ace V14-90 (Mn = 2,000, hydroxyl value = 56, acid value <0.3, linear solid type) [above, Made by Adeka];

For example, HS2H-200S (Mn = 2,000, hydroxyl value = 56, acid value <0.3, linear liquid type), HS2H-350S (Mn = 3,500, hydroxyl value = 32, acid value <0.3). , Linear liquid type), HS2H-500S (Mn = 5,000, hydroxyl value = 22, acid value <0.3, linear liquid type), HS2H-179A (Mn = 1,750, hydroxyl value = 64, acid value). <0.3, aromatic liquid-containing linear liquid type), HS2H-458T (Mn = 4,500, hydroxyl value = 25, acid value <0.3, aromatic ring-containing linear solid type), HS2F-237P (Mn = 2) , 000, hydroxyl value = 56, acid value <0.3, aromatic solid containing linear solid type)
[Above, Toyokuni Oil Co., Ltd.] and the like.

Polyamide polyol can be obtained by condensation reaction of a short-chain polyol at the molecular end of the polyamide formed by the condensation reaction with the polycarboxylic acid and polyamine. Most polyamide polyols have a surface tension of 40 mN / cm or more. Therefore, it belongs to the highly polar polyol (a1-2).
As the polyamine, any polyamine having two or more amino groups can be used without any particular limitation. For example, ethylenediamine, propylenediamine, butylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, bis- (3-aminopropyl) ether, 1,2-bis- (3-aminopropoxy) ethane, 1, 3-bis- (3-aminopropoxy) -2,2-dimethylpropane, α, ω-bis- (3-aminopropyl) polyethylene glycol ether, neopentyldiamine, 1,2-diaminobutane, 1,4-diamino Aliphatic diamines such as butane, hexamethylenediamine, trimethylhexamethylenediamine;

  For example, fats such as mensendiamine, isophoronediamine, 1,3- (bisaminomethyl) cyclohexane, 1,4- (bisaminopropyl) cyclohexane, 4,4′-methylenebis (2-methylcyclohexylamine), norbornanediamine Cyclic diamines;

  Examples thereof include polyamines having 3 or more amino groups such as methanetriamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, butane-1,1,4,4-tetraamine.

  Ketimines, which are the reaction products of these polyamines and ketones, are also included in the polyamines.

Of these, aliphatic diamines and alicyclic diamines are preferred as the polyamine, considering the solubility of the pressure-sensitive adhesive in the organic solvent described later and the wettability of the adherend.
Polyamines can be used alone or in combination of two or more. Polyamide polyols are preferably used in combination with other polyols from the viewpoint of solubility in organic solvents.
Thus, since the polyamide polyol is a highly polar polyol like the above-mentioned polyester polyol, it can maintain durability even under harsh environments such as high-temperature and high-humidity conditions. Since the solubility is low, the adhesion in the microviscous region is maintained over a long period of time, and the removability is also good. These may be used alone or in combination of two or more.

  As the polyamide polyol, for example, TPAE617 (Mn = 15,000, Tg = 90 ° C., hydroxyl value = 16, acid value = 1, linear solid type) [above, manufactured by T & K TOKA Co., Ltd.] It is done.

  The polycarbonate polyol is a known polycarbonate polyol having a structure represented by the following general formula [1] in its molecule, and most polycarbonate polyols have a surface tension of 40 mN / cm or more. -2).

General formula [1]
− [— O—R ¹ —O—CO—] _m —
(In the formula, R ¹ represents a divalent organic residue, and m represents an integer of 1 or more.)

The polycarbonate polyol can be obtained by (I) a reaction between a short-chain polyol and a carbonate ester, or (II) a reaction in which phosgene is allowed to act on the short-chain polyol in the presence of an alkali. .
Examples of the carbonate ester include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate.

Polycarbonate polyol has a highly polar carbonate structure as a linking group, so that the cohesive strength of the polyurethane resin (A) is increased and it has excellent heat resistance, hydrolysis resistance, or weather resistance. When used, it is excellent in re-peelability particularly in a severe environment. Among these, polycarbonate diols having a substituent having 2 to 22 carbon atoms in the side chain are preferable from the viewpoint of the viscosity and coating properties of the pressure-sensitive adhesive, or the processability of the adhesive film, and alkyl groups having 2 to 22 carbon atoms. Particularly preferred are polycarbonate diols having
Moreover, since it is a highly polar polyol like the above polyester polyol, durability can be maintained even under harsh environments such as high-temperature and high-humidity conditions, and compatibility with the ester compound (C) described later is low. Over a long period of time, the adhesion in the microviscous region is maintained, and the removability is also good. These may be used alone or in combination of two or more.

  As the polycarbonate polyols, commercially available products can be used, for example, oximer N112 (Mn = 1,000, Tg = 60 ° C., hydroxyl value = 112, acid value <0.5, linear type) [manufactured by Perstorp];

  Duranol T5651 (Mn = 1,000, hydroxyl value = 110, acid value <0.05, linear liquid type), Duranol T5652 (Mn = 2,000, hydroxyl value = 56, acid value <0.05, linear liquid type) ), Duranol T4671 (Mn = 1,000, hydroxyl value = 110, acid value <0.05, linear liquid type), Duranol T4672 (Mn = 2,000, hydroxyl value = 52, acid value <0.05, linear) Liquid type) [above, manufactured by Asahi Kasei Chemicals Corporation];

  ETERNACOLL UH-100 (Mn = 1,000, hydroxyl value = 110, acid value <0.05, linear liquid type), ETERNACOLLUH-200 (Mn = 2,000, hydroxyl value = 56, acid value <0.05, Linear liquid type) [above, manufactured by Ube Industries, Ltd.];

  BENEBiOL NL1010DB (Mn = 1,000, hydroxyl value = 110, acid value <0.05, linear solid type), BENEBiOL NL2010DB (Mn = 2,000, hydroxyl value = 56, acid value <0.05, linear solid type) ), BENEBiOLNL1010B (Mn = 1,000, hydroxyl value = 110, acid value <0.05, linear solid type), BENEBiOLNL2010B (Mn = 2,000, hydroxyl value = 56, acid value <0.05, linear solid type) [The above, manufactured by Mitsubishi Chemical Corporation];

  PLACEL CD205 (Mn = 500, hydroxyl value = 225, acid value <0.1, linear liquid type), PLACEL CD210 (Mn = 1,000, hydroxyl value = 116, acid value <0.1, linear wax type) PLACEL CD220 (Mn = 2,000, hydroxyl value = 56, acid value <0.1, linear wax type) [above, manufactured by Daicel Corporation];

  Kuraray polyol C-1065N (Mn = 1,000, hydroxyl value = 112, acid value <0.5, linear wax type), Kuraray polyol C-2065N (Mn = 2,000, hydroxyl value = 56, acid value < 0.5, linear wax type), Kuraray polyol C-1090 (Mn = 1,000, hydroxyl value = 112, acid value <0.5, linear liquid type), Kuraray polyol C-2090 (Mn = 2,000) , Hydroxyl value = 56, acid value <0.5, linear liquid type), Kuraray polyol C-3090 (Mn = 3,000, hydroxyl value = 37, acid value <0.5, linear liquid type), Kuraray polyol C -4090 (Mn = 4,000, hydroxyl value = 28, acid value <0.5, linear liquid type), Kuraray polyol C-5090 (Mn = 5,000, hydroxyl value = 22, acid value < 0.5, linear liquid type), Kuraray polyol C-1015N (Mn = 1,000, hydroxyl value = 112, acid value <0.5, linear liquid type), Kuraray polyol C-2015N (Mn = 2,000, Hydroxyl value = 56, acid value <0.5, linear liquid type) [manufactured by Kuraray Co., Ltd.] and the like.

  Polyols having a diene skeleton are polyols such as polybutadiene polyol and polyisoprene polyol, and have a surface tension of less than 40 mN / cm, and therefore belong to the low polarity polyol (a1-1). Also included are hydrogenated diene polyols whose diene skeleton is saturated with hydrogen atoms.

  As the polyols having a diene skeleton, commercially available products can be used. For example, NISSO G-1000 (Mn = 1,400, hydroxyl value = 73, acid value <0.5, linear liquid type), NISSO G-2000 (Mn = 2,000, hydroxyl value = 45, acid value <0.5, linear liquid type), NISSO G-3000 (Mn = 3,000, hydroxyl value = 27, acid value <0.5, linear liquid type) ), NISSO GI-1000 (Mn = 1,500, hydroxyl value = 67, acid value <0.5, hydrogenated linear liquid type), NISSO GI-2000 (Mn = 2,100, hydroxyl value = 47, acid value) <0.5, hydrogenated linear liquid type), NISSO GI-3000 (Mn = 3,000, hydroxyl value = 30, acid value <0.5, hydrogenated linear liquid type) [above, manufactured by Nippon Soda Co., Ltd.]

;
Poly bd R155HT (Mn = 1,000, hydroxyl value = 103, acid value <0.5, linear liquid type), Poly bd R45HT (Mn = 2,400, hydroxyl value = 47, acid value <0.5, linear) Liquid type), Poly ip (Mn = 2,000, hydroxyl value = 53, acid value <0.5, linear liquid type), EPOL (Mn = 2,000, hydroxyl value = 53, acid value <0.5, Hydrogenated linear liquid type) [above, manufactured by Idemitsu Kosan Co., Ltd.];

  Krasol LBH-P2000 (Mn = 2,100, hydroxyl value = 53, acid value <0.5, linear liquid type), Krasol LBH-P3000 (Mn = 3,200, hydroxyl value = 35, acid value <0.5) , Linear liquid type) [above, manufactured by Cray Valley, Inc.];

  Polytail H (Mn = 1,800, hydroxyl value = 65, acid value <0.5, linear liquid type) [above, manufactured by Mitsubishi Chemical Corporation] and the like.

  The polyols having a siloxane skeleton are polyols having a siloxane skeleton such as dimethylsiloxane diol, and the surface tension is less than 40 mN / cm, and therefore belong to the low polarity polyol (a1-1).

  As the polyols having a siloxane skeleton, commercially available products can be used. For example, KF6001 (Mn = 1,800, hydroxyl value = 62, acid value <0.5, linear liquid type), KF6002 (Mn = 3) , 000, hydroxyl value = 35, acid value <0.5, linear liquid type), KF6003 (Mn = 5,000, hydroxyl value = 2, acid value <0.5, linear liquid type) [Shin-Etsu Chemical Co., Ltd. Made];

  XF42-B0970 (Mn = 1,850, hydroxyl value = 60, acid value <0.5, linear liquid type) [above, manufactured by Momentive Performance Materials, Inc.];

  SF8427 (Mn = 2,400, hydroxyl value = 46.8, acid value <0.1, linear liquid type), SF8428 (Mn = 3,200, hydroxyl value = 35, acid value <0.1, linear liquid type) [The above is made by Toray Dow Corning Co., Ltd.].

  As the polyols containing at least one ionic functional group, since the structure contains an ionic functional group, the surface tension is 40 mN / cm or more, and it belongs to the highly polar polyol (a1-2).

  Of the polyols containing at least one ionic functional group, the ionic functional group is a quaternary ammonium group, a tertiary amino group, a carboxylate group, a carboxyl group, a sulfonate group, a sulfonic acid group, or a phosphonium group. , Ionic groups such as phosphinic acid groups and sulfate ester groups, and precursor groups thereof. Carboxyl groups, tertiary amino groups, etc. are not ionic groups, but can be easily converted to ionic groups by neutralization or quaternization with ammonia, tertiary amines, acetic acid, etc. Including.

  Examples of the polyol containing at least one ionic functional group include 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (hydroxymethyl) butyric acid, and 2,2-bis (hydroxymethyl) Carboxylic acid-containing polyol compounds such as herbic acid and 2,2-bis (hydroxymethyl) butanoic acid, and hydrogen groups of ammonia such as N, N-bis (2-hydroxypropyl) aniline and N-methyldiethanolamine as hydrocarbon groups And the like.

  The polyol (a1) is a low-polar polyol among short-chain polyols, a low-polar polyol among polyether polyols, a polyol having a diene skeleton, or a polyol having a siloxane skeleton, etc. Among the low-polar polyols (a1-1) and short-chain polyols having a surface tension of 20 mN / cm or more and less than 40 mN / cm, high-polar polyols among polyether polyols, high-polar polyols among polyether polyols, Highly polar polyols (a1-2) having a surface tension of 40 mN / cm or more and less than 60 mN / cm, such as polyester polyols, polyamide polyols, polycarbonate polyols, or polyols containing at least one ionic functional group And monomers constituting the polyol (a1), respectively. During a total of 100 wt%, the polyol (a1-1) units 50 to 99 mass%, it is preferred that polyols (a1-2) units are contained in 1 to 50 mass%, the proportion of. When the polyols (a1-1) and the polyol (a1-2) are contained in the above-mentioned range, it prevents foaming at the time of manufacturing the pressure-sensitive adhesive or coating the adhesive film, and also entrains. Since the bubbles can be easily removed, it is possible to reduce coating film defects and improve productivity. Moreover, since it becomes possible to reduce the self-adhesion property between adhesive films, it leads to reduction of loss and improvement of quality.

  In addition, durability that does not cause foaming, floating and peeling even under severe environments such as high-temperature and high-humidity conditions can be maintained, and compatibility with the ester compound (C) described below can be controlled, while suppressing migration. Since it is closed on the adhesive surface of the adhesive film, tack (adhesiveness) can be reduced over a long period of time, and the adhesive strength of the pressure-sensitive adhesive to the glass plate can be re-peeled (for example, adhesive strength of 10 (Less than 0.0 mN / 25 mm).

Thus, polyols (a1-1) having a surface tension of 20 mN / cm or more and less than 40 mN / cm (hereinafter also referred to as low-polar polyols) and surface tensions of 40 mN / cm or more and less than 60 mN / cm. The polyurethane resin (A) obtained by an appropriate mixing balance of a certain polyol (a1-2) (hereinafter sometimes referred to as “high polar polyols”) is used for the adhesive layer of the adhesive film having a micro phase separation structure. Slightly irregularities are formed on the surface of the adhesive layer, and self-adhesion and foaming can be suppressed, and since it contains the ester compound (C) described later, it is stable while maintaining flexibility from room temperature to low temperature. It is possible to obtain a wet spreadability. Moreover, the surface tension difference between the polyols (a1-1) having a surface tension of 20 mN / cm or more and less than 40 mN / cm and the polyols (a1-2) having a surface tension of 40 mN / cm or more and less than 60 mN / cm, When it is 2 mN / cm or more, the above-described stable wetting and spreading property is easily developed.
Further, by containing a trifunctional or higher functional polyol having 3 or more hydroxyl groups, it is possible to introduce a hydroxyl group that can be a crosslinking point with the reactive compound (B) described later into the polyurethane resin (A). Therefore, it is possible to control the balance between the removability and the adhesiveness and wettability of the slightly viscous region.

The number average molecular weight (Mn) of the polyol (a1-1) is preferably 2,000 to 10,000, and more preferably 2,500 to 8,000. Moreover, 400-4,000 are preferable and, as for the number average molecular weight (Mn) of a polyol (a1-2), 500-3,000 are more preferable. However, the said polyol (a1-1) is a number average molecular weight more than the said polyol (a1-2). When the number average molecular weight (Mn) of the polyol (a1-1) and the polyol (a1-2) is in the above range, the viscosity suitable for coating can be maintained, and the handling during coating processing is excellent.
Moreover, it becomes possible to give a moderate cohesive force and sufficient softness | flexibility to a polyurethane resin (A), and it becomes possible to express sufficient adhesiveness in a microviscous area | region. In addition, the adhesive film produced from the pressure-sensitive adhesive does not float or peel off even under a severe environment such as high temperature and high humidity.
When such polyol (a1-1) and polyol (a1-2) are used, a pressure-sensitive adhesive having excellent adhesion and wettability can be obtained. Moreover, application to a surface protection film is possible.
In addition, the said weight average molecular weight (Mw) and number average molecular weight (Mn) are the values of polystyrene conversion measured by the gel permeation chromatography (GPC) method. Details of the GPC measurement method are described in the Examples.

Among the polyols (a1), the hydroxyl value of the polyol (a1-1) or the polyol (a1-2) is preferably in the range of 5 to 300 mgKOH / g, more preferably in the range of 8 to 280 mgKOH / g. Yes, most preferably in the range of 4 to 200 mg KOH / g. When the hydroxyl value is in the above range, a pressure-sensitive adhesive having excellent adhesion and wettability is obtained in the same manner as the number average molecular weight (Mn), and application to a surface protective film becomes possible. Generally, if the hydroxyl value of a polyol is determined, the number average molecular weight is also determined, and it is known that the hydroxyl value and the number average molecular weight are linked.
The hydroxyl value (OHV) is a value measured according to JIS K1557-1: 2007, and the acid value (AV) is a value measured according to JIS K0070: 1992. Details of the measurement method are described in the examples. .

  In the said polyol (a1), when it has a glass transition temperature (Tg), it is although it does not specifically limit, Preferably it is -80-80 degreeC, More preferably, it is -70-40 degreeC. When the glass transition temperature (Tg) is in the above range, the pressure-sensitive adhesive containing the polyurethane resin (A) has sufficient tackiness and cohesive strength, so that cohesive failure of the adhesive layer is maintained while maintaining adhesiveness. Suppresses and prevents floating and peeling. The glass transition temperature (Tg) can be adjusted by appropriately selecting the type of polyol (a1) that is a constituent component. Moreover, it can also adjust to an appropriate glass transition temperature using 2 or more types of polyol (a1) from which glass transition temperature differs, for example, polyol (a1-1) and polyol (a1-2). Details of the measurement method are described in the examples.

  Transparency of adhesive layer using pressure-sensitive adhesive, maintenance of durability such as heat resistance and heat-and-moisture resistance, expression of adhesive force in micro-viscous area due to reduction of tack (stickiness), adhesion to adherends such as glass plates Used in combination with short-chain polyols having an alkyl group having 4 to 22 carbon atoms in the side chain as described above for fine adjustment of the surface tension of the pressure-sensitive adhesive as a whole, such as removability after wearing It is also possible to do. 0.1-20 mass% is preferable in the polyol (a1) whole quantity, and, as for the usage-amount of the short chain polyol which has a C4-C22 alkyl group, 0.5-15 mass% is more preferable. When the low molecular weight polyols having an alkyl group having 4 to 22 carbon atoms are in the above range, in addition to appropriate cohesive force, the pseudo crystallinity due to the molecular orientation of the high polar polyol (a1-2) is reduced. In addition, the pressure-sensitive adhesive can be improved in productivity by improving the bubble removal of the pressure-sensitive adhesive, and a pressure-sensitive adhesive having excellent wettability can be obtained.

In addition, it is preferable to use a polyol having three or more hydroxyl groups in combination with these diols in terms of forming a crosslinking point with a reactive compound described later and controlling the cohesive force. More preferably, the polyol having three or more hydroxyl groups is a low polarity polyol (a1-1) having a surface tension of 20 mN / cm or more and less than 40 mN / cm. When the polyol having three or more hydroxyl groups is the low-polarity polyol (a1-1), it is possible to suppress an increase in polarity associated with the hydroxyl group, and it is possible to suppress bubble scum and improve bubble removal.
Moreover, the usage-amount of the polyol which has 3 or more of hydroxyl groups has preferable 20-99 mass% in polyol (a1) whole quantity. When the polyols having 3 or more hydroxyl groups are within the above range, the adhesive film produced from the pressure-sensitive adhesive does not float or peel off even under a severe environment such as high temperature and high humidity, and after the peeling Good removability can be obtained without contaminating the adherend.

Here, the surface tension will be described.
The surface tension used in the present invention is calculated by the following Macleod-Sugden equation.

General formula [2]
σ ^1/4 = [P] · (ρ _L −ρ _G ) / M
Here, σ: surface tension [mN / cm], [P]: parachor, ρ _L : liquid density [g / cm ³ ], ρ _G : gas density [g / cm ³ ], M: molecular weight [ g / mol].
Also, in most cases, ρ _G is much smaller than ρ _{L and} can be ignored. If [rho _G is sufficiently smaller than [rho _L is, [rho _L becomes molar volume, if extended it to the resin, the following equation.

General formula [3]
σ ^1/4 = n · [P] _(unit) / n · Vm _(unit)
Here, σ: surface tension [mN / cm], [P] _(unit) : paracoll of unit, Vm: molar volume [cm ³ / mol], n: degree of polymerization.

  When the resin is a pressure sensitive adhesive containing a polyurethane resin or a crosslinking agent, each composition in the unit is calculated by molar volume ratio. Source: Macleod., Trans, Faraday Soc., 19, 38 (1923), Beer, FP and ER Johnston, Jr., Vector Mecjanics for Engineers-Dynamics, McGRAW-Hill International Editions, New York (1987), Robert C Reid, John M. Prausnitz, Bruce E. Poling, The Properties of GASES & LIQUIDS 4th Edition (1987). The calculated value of the surface tension is described in the examples.

<< Polyisocyanate (a2) >>
Next, the polyisocyanate (a2) unit, which is a monomer unit constituting the polyurethane urea resin (A), will be described.
As polyisocyanate (a2), it is a compound which can react with polyol (a1) and can create a hydroxyl-containing urethane resin (A), A conventionally well-known thing can be used. Examples of the polyisocyanate (a2) include aliphatic polyisocyanates, alicyclic polyisocyanates, and aromatic polyisocyanates, but aliphatic polyisocyanates that do not have an aromatic ring, or alicyclic polyisocyanates. In order to improve the flexibility of the polyurethane resin (A), the processability is further improved. Aliphatic means an acyclic carbon compound, and the cyclic carbon compound is defined as alicyclic.

  Examples of the polyisocyanate (a2) include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (also known as HDI), pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, and 1,3-butylene. Aliphatic diisocyanates such as diisocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate;

  For example, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (also known as IPDI), 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 (cyclohexyl isocyanate), 1,4-bis (isocyanatemethyl) cyclohexane, norbornene diisocyanate, dimer acid diisocyanate, octahydro-4,7-methano-1H -Alicyclic diisocyanates such as indenedimethyl diisocyanate;

  For example, 1,3-phenylene diisocyanate, 4,4′-diphenyl diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate (also known as 2,4-TDI), 2,6-tolylene diisocyanate (also known as : 2,6-TDI), 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4 ', 4 "-triphenyl Methane triisocyanate, 1,3-phenylene bismethylene diisocyanate (alias: m-XDI), 1,4-phenylene bismethylene diisocyanate (alias: p-XDI), 2,2′-diphenylmethane diisocyanate (alias: 2,2-MDI), 4,4'-diphenyl Tan diisocyanate (alias: 4,4-MDI), 1,3-naphthalenediyl diisocyanate (alias: 1,3-NDI), 1,5-naphthalenediyl diisocyanate (alias: 1,5-NDI), ω, ω ′ Diisocyanate-1,3-dimethylbenzene, ω, ω′-diisocyanate-1,4-dimethylbenzene, ω, ω′-diisocyanate-1,4-diethylbenzene, 1,4-tetramethylxylylene diisocyanate, 1,3 -Aromatic diisocyanates such as tetramethylxylylene diisocyanate;

  Examples thereof include polyisocyanates having three or more isocyanate groups such as lysine triisocyanate, triphenylmethane-4,4 ′, 4 ″ -triisocyanate, and methylsilanetriyl trisisocyanate.

The polyisocyanate (a2) may have an aromatic ring as described above or may have three or more isocyanate groups, but non-yellowing type such as aliphatic polyisocyanates and alicyclic polyisocyanates, Alternatively, a hardly yellowing type diisocyanate is preferable because durability under high temperature environment or high temperature and high humidity environment, wet spreadability and removability are further improved.
Among these, aliphatic polyisocyanates such as hexamethylene diisocyanate (also known as HDI), alicyclic polyisocyanates such as isophorone diisocyanate (also known as IPDI) and 4,4′-methylenebis (cyclohexyl isocyanate) (also known as hydrogenated MDI). It is preferable to use diisocyanates having no aromatic ring such as isocyanates.

The polyurethane resin (A) is a hydroxyl group-containing resin obtained by polymerizing the polyol (a1) and the polyisocyanate (a2).
The weight-average molecular weight (Mw) of the polyurethane resin (A) is 10,000 to 500,000 in order to achieve both the coating suitability of the pressure-sensitive adhesive and the cohesive strength of the adhesive layer and the adhesive layer at a high level. Is preferable, and it is more preferable that it is 30,000-400,000. When Mw is in the above range, the cohesive force and the like are further improved, so that floating / peeling can be further suppressed, and wetting and spreading properties are further improved. In addition, the said weight average molecular weight and number average molecular weight are the values of polystyrene conversion measured by the gel permeation chromatography (GPC) method. Details of the GPC measurement method are described in the Examples.

  0.1-50 mgKOH / g is preferable and, as for the hydroxyl value (OHV) of a polyurethane resin (A), 1-35 mgKOH / g is more preferable. When the hydroxyl value (OHV) is in the above range, the crosslinking reaction with the reactive compound (B) having a functional group capable of reacting with a hydroxyl group becomes more efficient. While maintaining the above, it becomes easy to develop an adhesive force in a slightly viscous region, and the removability is improved. In addition, it is possible to reduce self-adhesion and to improve bubble removal. In addition, after sticking, it is easy to maintain durability such as heat resistance and moist heat resistance even under severe conditions such as high temperature and high humidity. In the case of further peeling, contamination such as cloudiness and adhesive residue is suppressed on the adherend.

  The solution viscosity of the polyurethane resin (A) is not particularly limited and can be appropriately selected depending on the application of the pressure-sensitive adhesive. The solution viscosity is preferably 1,000 to 10,000 mPa · s (25 ° C.) at a nonvolatile content concentration of 50 mass%. When the solution viscosity is within this range, it is preferable because productivity and coating processability associated with reduction of foam removal properties are improved while maintaining a sufficient cohesive force.

  The surface tension of the polyurethane resin (A) is preferably 30 mN / cm or more and less than 40 mN / cm, and more preferably 35 mN / cm or more and less than 40 mN / cm. When the surface tension is in the above range, the pressure-sensitive adhesive using the polyurethane resin (A) is bonded to the produced adhesive film even when a reactive compound (B) or an ester compound (C) described later is mixed. The surface tension of the surface is in the range of 20 mN / cm or more and less than 40 mN / cm, and exhibits adhesiveness in a fine-viscosity region for highly polar adherends such as glass plates (40 mN / cm or more and less than 60 mN / cm). And the removability is improved.

  The polyurethane resin (A) preferably contains 70 to 99% by mass of the polyol (a1) and 1 to 30% by mass of the polyisocyanate (a2) in all the constituent monomers, and the polyol (a1) 80 to 80%. It is more preferable that it is contained in a range of 98% by mass and 2 to 20% by mass of polyisocyanate (a2). When the polyol (a1) and the polyisocyanate (a2) are in the above range, the viscosity suitable for coating is maintained, so that the polyurethane resin (A) is excellent in handling during coating. When this polyurethane resin (A) is used as a pressure-sensitive adhesive, moderate cohesive force and sufficient flexibility can be obtained. Therefore, when the produced adhesive film is attached to an adherend such as a glass plate, it spreads wet. In addition to being excellent in removability and removability, it is difficult to lift and peel off even under severe conditions such as high temperature and high humidity after pasting, and can be applied to a surface protective film.

<Reactive compound (B) having a functional group capable of reacting with a hydroxyl group>
Next, the reactive compound (B) having a functional group capable of reacting with a hydroxyl group will be described.
In this specification, the reactive compound (B) having a functional group capable of reacting with a hydroxyl group (hereinafter referred to as the reactive compound (B)) is 0.1 to 50 with respect to 100 parts by mass of the polyurethane resin (A). It is necessary to contain a mass part, and 1-30 mass parts is more preferable. When the reactive compound (B) is in this range, not only the heat resistance and moist heat resistance are improved by the crosslinking reaction with the hydroxyl group contained in the polyurethane resin (A), but also the adhesive layer in a harsh environment. Floating, peeling, or foaming can be suppressed, and application to a surface protective film becomes possible.

Moreover, since the polyurethane resin (A) has a hydroxyl group, examples of the functional group capable of reacting with the hydroxyl group in the reactive compound (B) include an isocyanate group, an alkoxysilyl group, and a methylol group.
Examples of the reactive compound (B) include polyisocyanate (b1), silane compound (b2), and methylolmelamine compound (b3). Among these, the reactive compound (B) is preferably a compound having two or more functional groups capable of reacting with the hydroxyl group of the polyurethane resin (A) in order to impart crosslinkability.
In particular, polyisocyanate (b1) is preferable because it has excellent adhesion after the crosslinking reaction and adhesion to the substrate (G) described later.

  The polyisocyanate (b1) is a compound having a plurality of isocyanate groups in the molecule. Polyisocyanate (b1) can be classified into aliphatic polyisocyanates, alicyclic polyisocyanates, or aromatic polyisocyanates. In addition, about aliphatic polyisocyanate, alicyclic polyisocyanate, or aromatic polyisocyanate, the polyisocyanate demonstrated by the said polyisocyanate (a2) can be used.

  The polyisocyanate (b1) is preferably a compound having 3 or more isocyanate groups. Such polyisocyanate (b1) is a polyisocyanate having three or more isocyanate groups as described above, and various polyisocyanates such as 2-methylpentane-2,4-diol and trimethylolpropane polyols. Adducts, trimers having an isocyanurate ring, and the like can be preferably used. Polyphenylmethane polyisocyanate (also known as PAPI) and these polyisocyanate-modified products are also preferred. As the polyisocyanate-modified product, a carbodiimide group, a uretdione group, a uretonimine group, a burette group reacted with water, a group of isocyanurate groups, or a modified product having two or more of these groups can be used. The reaction product of a polyol and a diisocyanate can also be used as a compound having at least two isocyanate groups. In addition, as the polyisocyanate (b1), a blocked isocyanate in which an isocyanate group is blocked using a blocking agent can also be used.

  In the case of using the polyisocyanate (b1), a known catalyst can be used as necessary for promoting the reaction between the hydroxyl group of the polyurethane urea resin (A) and the isocyanate group. Examples of the catalyst include tertiary amine compounds and organometallic compounds.

  Examples of the tertiary amine compound include triethylamine, triethylenediamine, N, N-dimethylbenzylamine, N-methylmorpholine, diazabicycloundecene (also known as DBU), and the like.

Examples of the organometallic compound include a tin compound and a non-tin compound.
Examples of the tin compound include dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimaleate, dibutyltin dilaurate (also known as DBTDL), dibutyltin diacetate, dibutyltin sulfide, tributyltin sulfide, tributyltin oxide, Examples include tributyltin acetate, triethyltin ethoxide, tributyltin ethoxide, dioctyltin oxide, tributyltin chloride, tributyltin trichloroacetate, and tin 2-ethylhexanoate.
Examples of non-tin compounds include titanium compounds such as dibutyltitanium dichloride, tetrabutyltitanate, and butoxytitanium trichloride, lead compounds such as lead oleate, lead 2-ethylhexanoate, lead benzoate, and lead naphthenate. -Iron compounds such as iron ethylhexanoate and iron 2,4-pentadionate, cobalt compounds such as cobalt benzoate and cobalt 2-ethylhexanoate, zinc compounds such as zinc naphthenate and zinc 2-ethylhexanoate And zirconium naphthenate.
Among these, diazabicycloundecene (alias: DBU), dibutyltin dilaurate (alias: DBTDL), tin 2-ethylhexanoate and the like are preferable in terms of reactivity and hygiene.
The catalyst can be used alone or in combination of two or more.

  In particular, polyisocyanate (b1) is an adduct of diisocyanate such as HDI, TDI, MDI, and IPDI with trimethylolpropane, a burette reacted with water, and an isocyanurate ring in terms of crosslinking reactivity. The body is preferably used, but from the standpoint of maintaining adhesive strength in the microviscous region and reducing density, adducts with HDI and IPDI trimethylolpropane that do not have an aromatic ring, burettes that have reacted with water, isocyanurates Ring trimers are particularly preferred.

  Examples of the silane compound (b2) include alkyl alkoxysilanes, aryl alkoxysilanes, carbamate alkoxysilanes, vinyl alkoxysilanes, halogen alkoxysilanes, (meth) acryloyl alkoxysilanes, mercapto alkoxysilanes, and imidazole alkoxys. Examples include alkoxysilanes having an alkoxyl group such as silane, isocyanate-based alkoxysilane, epoxy-based alkoxysilane, and amino-based alkoxysilane.

  For example, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltriacetoxysilane, methyltris (methoxyethoxy) silane, methyltris (methoxypropoxy) silane, Ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, propyltrimethoxysilane, propyltriethoxysilane, propyltriisopropoxysilane, butyltrimethoxysilane, butyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxy Silane, octyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, silane Chlorotrimethoxysilane, cyclohexyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldiisopropoxysilane, dimethyldiacetoxysilane, dimethylbis (methoxyethoxy) silane, dimethylbis (methoxypropoxy) silane, diethyldimethoxysilane , Diethyldiethoxysilane, diethyldiisopropoxysilane, diethyldiacetoxysilane, methylethyldimethoxysilane, methylethyldiethoxysilane, methylethyldiisopropoxysilane, methylethyldiacetoxysilane, methylpropyldimethoxysilane, methylpropyldiethoxy Alkyl alkoxysilanes such as silane, methylpropyldiisopropoxysilane, methylpropyldiacetoxysilane, etc.

  For example, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriisopropoxysilane, phenyltriacetoxysilane, tolyltrimethoxysilane, tolyltriethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, diphenyldiisopropoxysilane, diphenyldi Aryl-based alkoxysilanes such as acetoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, methylphenyldiisopropoxysilane, methylphenyldiacetoxysilane;

  For example, (3-carbamateethyl) propyltriethoxysilane, (3-carbamateethyl) propyltrimethoxysilane, (3-carbamateethyl) propyltripropoxysilane, (3-carbamatepropyl) propyltriethoxysilane, (3-carbamatepropyl ) Propyltrimethoxysilane, (3-carbamatepropyl) propyltripropoxysilane, (3-carbamatebutyl) propyltriethoxysilane, (3-carbamatebutyl) propyltrimethoxysilane, (3-carbamatebutyl) propyltripropoxysilane, (3-carbamatebutyl) butyltripropoxysilane, (3-carbamatebutyl) propylmethyldiethoxysilane, (3-carbamatepentyl) propyltriethoxysilane (3-carbamatehexyl) propyltriethoxysilane, (3-carbamateoctyl) pentyl riboxysilane, (3-carbamateethyl) propylsilyltrichloride, (3-carbamateethyl) propyltrimethylsilane, (3-carbamateethyl) Carbamate alkoxysilanes such as) propyldimethylsilane, 3-carbamateethyl) propyltributylsilane, (3-carbamateethyl) ethyl-p-xylenetriethoxysilane, (3-carbamateethyl) -p-phenylenetriethoxysilane;

  For example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, vinyltriacetoxysilane, vinyltris (methoxyethoxy) silane, vinyltris (methoxypropoxy) silane, allyltrimethoxysilane, allyltriethoxysilane, divinyldimethoxysilane , Divinyldiethoxysilane, divinyldiisopropoxysilane, divinyldiacetoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, methylvinyldiisopropoxysilane, methylvinyldiacetoxysilane, diallyldimethoxysilane, diallyldiethoxysilane, Diallyldiisopropoxysilane, methylallyldimethoxysilane, methylallyldiethoxysilane, methylallyldiisopropoxy Orchids, vinyl and allylic alkoxysilanes such as methyl allyl diacetoxy silane;

  For example, chloromethyltrimethoxysilane, chloromethyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, 3-chloropropylmethyldiethoxysilane, 3,3,3-trifluoropropyltrimethoxy Halogen-based alkoxysilanes such as silane, 3,3,3-trifluoropropyltriethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropylmethyldiethoxysilane, 3,3,3-trifluoropropylmethyldimethoxysilane ;

  For example, 3-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, 3-acryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ- (Meth) acryloyl-based alkoxysilanes such as acryloxypropylmethyldimethoxysilane;

  For example, mercapto alkoxysilanes such as 3-mercaptopropyltrimethoxylane, 3-mercaptopropyltriethoxysilane, and γ-mercaptopropylmethyldiethoxysilane;

  For example, imidazole alkoxysilanes such as 3- (2-imidazolin-1-yl) propyltrimethoxysilane and 3- (2-imidazolin-1-yl) propyltriethoxysilane;

  For example, isocyanate-based alkoxysilanes such as 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltripropoxysilane;

  For example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 2- ( Epoxy-based alkoxysilanes such as 3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyldiethoxysilane;

  For example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-aminopropylethyldiethoxysilane, 3-aminopropyldimethylethoxy Silane, N- (2-aminomethyl) 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropyltrimethoxysilane, 3- (2-aminoethylaminopropyl) trimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyldimethoxysilane, 2-aminoethylaminomethyltrimethoxysilane, 3- [2- (2-aminoethylaminoethylamino) propyl] trimethoxysilane, methyltris (2-aminoethoxy) ) Silane Butylaminomethyltrimethoxysilane, 2- (2-aminoethylthioethyl) trimethylsilane, 2- (2-aminoethylthioethyl) methyldiethoxysilane, 3-allylaminopropyltrimethoxysilane, 3-cyclohexylaminopropyltri Methoxysilane, 2-cyclohexylaminoethylthiomethyltrimethoxysilane, 3- (N-phenyl) aminopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, N- [2- (vinylbenzylamino) ethyl] -3 -Aminopropyltrimethoxysilane, 2- (2-aminoethylthioethyl) triethoxysilane, 3-piperazinopropylmethyldimethoxysilane, 3-piperazinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane Amino-based alkoxysilanes such like.

Moreover, the silane compound (b2) can also use an oligomeric silane obtained by oligomerizing a mixture of two or more silanes by hydrolysis and condensation.
Among these, a silane compound having no aromatic ring is preferable in terms of wettability with respect to an adherend.
The silane compound (b2) is methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyl in terms of condensation reaction with the hydroxyl group of the polyurethane resin (A) and improvement in adhesion to the substrate surface. Alkyl alkoxysilanes such as triethoxysilane, 3-mercaptopropyltrimethoxysilane, mercaptoalkoxysilanes such as 3-mercaptopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxy Silanes, epoxy alkoxysilanes such as 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, imidazole alkoxysilanes such as 3- (2-imidazolin-1-yl) propyltriethoxysilane, 3-aminopropyltri Methoxysila 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-aminopropylethyldiethoxysilane, 3-aminopropyldimethylethoxysilane, 2-cyclohexylaminoethylthiomethyl Amino alkoxysilanes such as trimethoxysilane and trimethylsilyldimethylamine, and isocyanate alkoxysilanes such as 3-isocyanatopropyltriethoxysilane are preferred. The silane compound (b2) can be used alone or in combination of two or more.

Examples of the methylol melamine compound (b3) include methylol melamine derivatives obtained by condensing melamine and formaldehyde, and compounds obtained by reacting these with a lower alcohol such as methyl alcohol, ethyl alcohol, or isopropyl alcohol. . Examples of the methylol melamine compound (b3) include monomethylol melamine, dimethylol melamine, trimethylol melamine (also known as cearicin), tetramethylol melamine, pentamethylol melamine, pentamethoxymethylol melamine, hexamethylol melamine, hexamethoxymethylol melamine, Hexaethoxymethylmelamine, hexakis- (methoxymethyl) melamine, N, N ′, N ″ -trimethyl-N, N ′, N ″ -trimethylolmelamine, N, N ′, N ″ -trimethylolmelamine, N, N Examples include ', N ″ -tributyl-N, N ′, N ″ -trimethylol melamine, (hydroxymethyl) pentakis (methoxymethyl) melamine, hexamethylol melamine pentamethyl ether and the like.
Among these, pentamethoxymethylol melamine and hexamethoxymethyl melamine are preferable from the viewpoint of condensation reaction with the hydroxyl group of the polyurethane resin (A) and improvement in adhesion to the substrate surface.
A methylol melamine type compound (b3) can be used individually or in combination of 2 or more types.

  In addition to the polyisocyanate (b1), the silane compound (b2), and the methylolmelamine compound (b3), the reactive compound (B) is excellent in adhesiveness after crosslinking reaction and adhesion to a substrate. Polyisocyanate (b1) is preferable in terms of achieving a high level of flexibility and wettability by controlling the crosslinking density.

<Ester compound (C)>
Next, the ester compound (C) will be described.
It is essential that the pressure-sensitive adhesive of the present invention contains an ester compound (C).
The ester compound (C) can impart a plastic effect to the adhesive layer after coating, and can further improve the wetting and spreading properties of the adhesive film to an adherend such as a glass plate. Moreover, after sticking an adhesive film to a to-be-adhered body, it becomes possible to lighten the peeling at the time of peeling, and to reduce the self-adhesiveness between adhesive surfaces, so that workability is improved. Further, contamination such as adhesive residue on the adherend can be suppressed.

  The ester compound (C) includes an esterified product of a fatty acid such as aliphatic carboxylic acid, aliphatic phosphoric acid, and aliphatic boric acid and a fatty alcohol containing a hydroxyl group, and an epoxy-modified ester obtained by further epoxy-modifying these esterified products. It is a monster. The ester compound (C) does not include an ethylenically unsaturated double bond-containing compound and an organic solvent. The ester compound (C) is roughly classified into a fatty acid ester (c1), a phosphoric acid ester (c2), and a boric acid ester (c3).

  The fatty acid ester (c1) is (1) an ester of a monobasic acid or polybasic acid having 4 to 22 carbon atoms and a monovalent alcohol having 22 or less carbon atoms, and (2) one having 18 to 22 carbon atoms. An ester of a basic acid and a tetravalent or lower alcohol having 22 or less carbon atoms and an epoxy-modified ester obtained by further modifying the ester of (3), (1) or (2) with an epoxy are preferable.

  Examples of saturated monobasic acids having 4 to 22 carbon atoms include butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, 2-ethylcaproic acid, pelargonic acid, capric acid, lauric acid, myristic acid, pentadecylic acid, Examples include palmitic acid, margaric acid, stearic acid, isostearic acid, arachidic acid, and behenic acid.

  Unsaturated monobasic acids having 4 to 22 carbon atoms are crotonic acid, palmitoleic acid, sabienoic acid, oleic acid, elaidic acid, vaccenic acid, linoleic acid, linolenic acid, pinolenic acid, eleostearic acid, stearidonic acid, boseopentaene Acid, gadoleic acid, icosadienoic acid, icosatrienoic acid, eicosenoic acid, eicosadienoic acid, eicosatrienoic acid, eicosatetraenoic acid, eicosapentaenoic acid, mead acid, arachidonic acid, erucic acid, docosadienoic acid, adrenic acid, ozbond acid, Examples include sardine acid and docosahexaenoic acid.

  Examples of the saturated dibasic acid having 4 to 22 carbon atoms include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, 1,10-decanedioic acid, and 1,12-dodecanediic acid. Examples include acids, 1,12-octadecanedioic acid, eicosanedioic acid, and the like.

  Examples of the unsaturated dibasic acid having 4 to 22 carbon atoms include maleic acid, fumaric acid, mesaconic acid, muconic acid and the like.

  Polybasic acids having 4 to 22 carbon atoms are isocitrate, aconitic acid, 1,2,3-propanetricarboxylic acid, 1,2,3-propenetricarboxylic acid, camphoric acid, isocamphoronic acid, ethanetetracarboxylic acid, butane. Examples thereof include tetracarboxylic acid, octanetetracarboxylic acid, ethylenetetracarboxylic acid, butenetetracarboxylic acid and the like.

  The monovalent saturated alcohol having 22 or less carbon atoms is, for example, methanol, ethanol, propanol, butanol, hexanol, 2-ethylhexanol, april alcohol, pelargon alcohol, caprin alcohol, undecyl alcohol, 2-butyloctanol, lauryl. Alcohol, tridecyl alcohol, myristyl alcohol, pentadecyl alcohol, cetanol (also known as palmityl alcohol), isocetyl alcohol, heptadecanol, stearyl alcohol, isostearyl alcohol, nonadecyl alcohol, eicosanol (also known as arachidyl alcohol) Octyldodecyl alcohol, heneicosanol, behenyl alcohol, 2- (2-butoxyethoxy) ethyl alcohol, 2- 2-methoxyethoxy) ethyl alcohol, and or alkylene oxide adducts thereof, and the like.

  Examples of the monovalent unsaturated alcohol having 22 or less carbon atoms include palmitoleyl alcohol, elaidyl alcohol, oleyl alcohol, linoleyl alcohol, elide linoleyl alcohol, linolenyl alcohol, erucyl alcohol, and the like. An alkylene oxide adduct of

  Examples of the divalent to tetravalent alcohol having 18 or less carbon atoms include diols having 22 or less carbon atoms, ricinoleyl alcohol, glycerin, diglycerin, polyglycerin, and trimethylolpropane mentioned in the polyol (a1). , Pentaerythritol, sorbitol, etc., or alkylene oxide adducts thereof.

  In the fatty acid ester (c1), (1) as an ester of a monobasic acid or polybasic acid having 4 to 22 carbon atoms and a monohydric alcohol having 22 or less carbon atoms, for example, isopropyl butyrate, isopropyl valerate, Isopropyl caproate, lauryl caproate, stearyl caproate, cetyl caprylate, stearyl caprylate, cetyl 2-ethyl caproate, isocetyl 2-ethyl caproate, stearyl 2-ethyl caproate, stearyl caprate, hexyldecyl dimethyloctanoate , Methyl laurate, butyl laurate, hexyl laurate, cetyl laurate, stearyl laurate, isopropyl myristate, isocetyl myristate, stearyl myristate, myristyl myristate, octyldodecyl myristate, palmi Isopropyl isopropyl, 2-ethylhexyl palmitate, lauryl palmitate, isostearyl palmitate, methyl stearate, butyl stearate, 2-ethylhexyl stearate, isocetyl stearate, stearyl stearate, octyldodecyl stearate, isotridecyl stearate, Monobasic acids and monohydric alcohols such as isosecil isostearate, isopropyl isostearate, cholesteryl isostearate, isostearyl behenate, polyoxyethylene lauric acid methyl ester, polyoxyethylene lauric acid stearyl ester, polyoxyethylene stearic acid isopropyl ester Saturated fatty acid monoesters of

  For example, lauryl methacrylate, methyl crotonate, butyl crotonate, methyl palmitate, octyldodecyl palmitate, methyl sabiate, methyl oleate, methyl oleate, isopropyl oleate, butyl oleate, octyl oleate, octyl oleate Dodecyl, methyl elaidate, methyl vaccenate, methyl linoleate, ethyl linoleate, isopropyl linoleate, butyl linoleate, octyldodecyl linoleate, ethyl linolenate, octyldodecyl linolenate, methyl pinolenate, methyl pinolenate, eleeo Methyl stearate, methyl stearidate, butyl stearidate, methyl boseopentenoate, methyl gadoleate, methyl icosadienoate, methyl icosatrienoate, eicosene Methyl, ethyl eicosenoate, isopropyl eicosenoate, methyl eicosadienoate, methyl eicosatrienoate, methyl eicosatetraenoate, methyl eicosapentaenoate, methyl medeate, methyl arachidate, methyl erucate, methyl docosadienoate, adrenic acid Unsaturated fatty acid monoesters of monobasic acids and monohydric alcohols such as methyl, methyl ozbondate, methyl sardate, methyl docosahexaenoate;

  For example, diethyl succinate, diisopropyl succinate, dibutyl succinate, dimyristyl succinate, diethyl glutarate, diethyl 3-methylglutarate, dibutyl glutarate, diethyl adipate, diisopropyl adipate, bis (2-butoxyethyl) adipate Bis (2- (2-butoxyethoxy) ethyl adipate), bis (2-ethylhexyl) adipate, diisononyl adipate, diisodecyl adipate, diisostearyl adipate, diethyl pimelate, dibutyl pimelate, diethyl suberate , Diethyl azelate, diethyl sebacate, diisopropyl sebacate, dibutyl sebacate, diisocetyl sebacate, dibutyloctyl sebacate, diisostearyl sebacate, dibuty 1,10-decandioate Saturated fatty acid diester of a dibasic acid and a monohydric alcohol and the like;

  For example, dimethyl maleate, diethyl maleate, diisopropyl maleate, dibutyl maleate, dimethyl fumarate, diisopropyl fumarate, dimethyl mesaconate, diethyl mesaconate, diisopropyl mesaconate, dibutyl mesaconate, dimethyl muconate, diethyl muconate, etc. An unsaturated fatty acid diester of a dibasic acid and a monohydric alcohol;

Trimethyl isocitrate, trimethyl aconitate, trimethoxypolyoxyethylene aconite, trimethyl 1,2,3-propanetricarboxylate, trimethyl 1,2,3-propenetricarboxylate, trimethyl camphorate, trimethoxypolyoxyethylene camphorate, Trimethyl isocamphorate, tetramethyl ethanetetracarboxylate, dimethylbutanetetracarboxylate, trimethylbutanetetracarboxylate, tetramethylbutanetetracarboxylate, tetramethyloctanetetracarboxylate, tetramethylethylenetetracarboxylate, tetramethylbutenetetracarboxylate Unsaturated polyvalent esters of polybasic acids such as monohydric alcohols;

  For example, monobasic acids and monovalents such as monoisopropyl succinate, monoethyl adipate, monoisodecyl adipate, monoisopropyl sebacate, monoisostearyl sebacate, monoethyl mesaconate, monoisopropyl mesaconate, dimethyl aconite, dimethyl camphorate And unsaturated fatty acid monoesters with alcohols.

  In addition, in the fatty acid ester (c1), (2) as an ester of a monobasic acid having 4 to 22 carbon atoms and a tetravalent or lower alcohol having 22 or less carbon atoms, for example, diethylene glycol dibutyrate or divaleric acid Diethylene glycol, dipolyoxyethylene divalerate, neopentyl glycol dicaproate, diethylene glycol dicaproate, triethylene glycol dicaproate, polyoxyethylene dicaproate, dipropylene glycol dicaproate, polyoxypropylene dicaproate, diethylene glycol dienanthate, dicaprylic acid Neopentyl glycol, ethylene glycol dicaprylate, propylene glycol dicaprylate, polyoxyethylene dicaprylate, neopentyl glycol di2-ethylcaproate, di-2-ethylcap Diethylene glycol ronate, polyoxyethylene di-2-ethylcaproate, polyoxypropylene di2-ethylcaproate, dipropylene glycol di2-ethylcaproate, diethylene glycol dipelargonate, diethylene glycol dicaprate, propylene glycol dicaprate, dicapric acid Polyoxyethylene, dipentyl glycol dilaurate, diethylene glycol dilaurate, polyoxyethylene dilaurate, polyoxypropylene dilaurate, neopentyl glycol dimyristate, diethylene glycol dimyristate, dipropylene glycol dimyristate, polyoxydimyristate Propylene, dioxymyristate polyoxyethylene, dimyristate polyoxypropylene, dipentadec Diethylene glycol acid, neopentyl glycol dipalmitate, diethylene glycol dipalmitate, polyoxyethylene dipalmitate, diethylene glycol dimargarate, neopentyl glycol distearate, ethylene glycol distearate, diethylene glycol distearate, polyoxyethylene distearate, polyoxystearate Saturated monobase such as oxypropylene, ricinoleyl distearate, diethylene glycol diisostearate, polyoxyethylene diisostearate, propylene glycol diisostearate, polyoxypropylene diisostearate, diethylene glycol diarachidate, diethylene glycol dibehenate, polyoxyethylene bisphenol A laurate, etc. Saturated fatty acid diesters of acids and dihydric alcohols (also known as diols);

  For example, ethylene glycol dicrotonate, propylene glycol dicrotonate, polyoxyethylene dicrotonate, ethylene glycol dipalmitoleate, ethylene glycol disabienoate, ethylene glycol dioleate, polyoxyethylene dioleate, neopentyl glycol dioleate, hexyl glycol dioleate , Propylene glycol dioleate, polyoxypropylene dioleate, ethylene glycol dieleic acid, polyoxypropylene dielaidate, ethylene glycol dibacate, ethylene glycol dilinoleate, propylene glycol dilinoleate, neopentyl glycol dilinoleate, ethylene glycol dilinolenate, dilinolene Acid polyoxyethylene, propylene dilinolenate Recall, Polyoxyethylene dilinoleate, Neopentyl glycol dilinolenate, Ethylene glycol dipinolenate, Ethylene glycol dieleostearate, Ethylene glycol distearide, Ethylene glycol diboseopentaenoate, Ethylene glycol digadelate, Ethylene glycol diicosadienoate, Diicosatriene Ethylene glycol, dieicosenoic acid ethylene glycol, dieicosadienoic acid ethylene glycol, dieicosatrienoic acid ethylene glycol, dieicosatetraenoic acid ethylene glycol, dieicosapentaenoic acid ethylene glycol, dimedic acid ethylene glycol, diarachidic acid ethylene glycol, dierucic acid ethylene glycol, Didocosadienoic acid ethylene glycol, dia Unsaturated monobasic acids and dihydric alcohols such as ethylene glycol renate, ethylene glycol ethylene glycol, ethylene glycol diwasate, ethylene glycol didocosahexaenoate, polyoxyethylene di-2-ethylcaproate ether / caprate (also known as: Diols) and unsaturated fatty acid diesters;

  For example, caproic acid triglyceride, caprylic acid triglyceride, 2-ethylcaproic acid triglyceride, 2-ethylcaproic acid polyoxyethylene triglyceride, 2-ethylcaproic acid polyoxypropylene triglyceride, pelargonic acid triglyceride, capric acid triglyceride, lauric acid triglyceride, lauric acid Acid polyoxyethylene triglyceride, myristic acid triglyceride, myristic acid polyoxyethylene triglyceride, pentadecyl acid triglyceride, palmitic acid triglyceride, palmitic acid polyoxyethylene triglyceride, margaric acid triglyceride, stearic acid diglyceride, stearic acid triglyceride, stearic acid polyoxyethylene triglyceride , Isostearic acid triglyceride Arachidic acid triglyceride, behenic acid triglyceride, tricaproic acid trimethylolpropane, tricaprylic acid trimethylolpropane, tri-2-ethylcaproic acid trimethylolpropane, tri-2-ethylcaproic acid polypolyoxyethylene trimethylolpropane, tricapric acid trimethylolpropane, dilaurin Trimethylol propane trimethylol propane, trimethylol propane trilaurate, polyethylene glycol trimethylol trilaurate, trimethylol propane dimyristate, trimethylol propane trimyristate, trimethylol propane tripalmitate, trimethylol propane tripalmitate, trimethylol propane trimethyl Trimethylolpropane stearate, polyoxytristearate Tylene trimethylolpropane, trimethylolpropane triisostearate, pentaerythritol tetracaproate, pentaerythritol tetracaprylate, pentaerythritol tetra2-ethylcaproate, pentaerythritol tetracaprate, pentaerythritol tetralaurate, pentaerythritol tetramyristate Pentaerythritol monopalmitate, pentaerythritol dipalmitate, pentaerythritol tripalmitate, pentaerythritol tetrapalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate, tetraisostearin Pentaerythritol acid, Tet 2-Glyceryl tetraethyl caproate, diglyceryl tetralaurate, diglyceryl tetramyristate, diglyceryl tetrapalmitate, diglyceryl tetrastearate, polyoxyethylene sorbitol hexa-2-ethylcaproate, polyoxyethylene hexalaurate Sorbit, polyoxyethylene sorbitol hexamyristic acid, polyoxyethylene sorbite hexapalmitate, polyoxyethylene sorbitol tristearate, polyoxyethylene sorbitol hexastearate, polyoxyethylene sorbitol hexaisostearate, polyglyceryl tetralaurate, tetrastearic acid Saturated fatty acid polyvalent esters of saturated monobasic acids and polyhydric alcohols such as polyglyceryl and polyglyceryl hexastearate;

  For example, crotonic acid triglyceride, palmitoleic acid triglyceride, sabienoic acid triglyceride, oleic acid diglyceride, oleic acid triglyceride, elaidic acid triglyceride, vaccenic acid triglyceride, linoleic acid diglyceride, linoleic acid triglyceride, linolenic acid diglyceride, linolenic acid triglyceride, pinolenic acid triglyceride, Eleostearic acid triglyceride, stearidonic acid triglyceride, boseopentaenoic acid triglyceride, gadedoic acid triglyceride, icosadienoic acid triglyceride, icosatrienoic acid triglyceride, eicosenoic acid triglyceride, eicosadienoic acid triglyceride, eicosatrienoic acid triglyceride, eicosatetraenoic acid triglyceride, eicosapentaenoic acid Trig Seride, Mead acid triglyceride, Arachidonic acid triglyceride, Erucic acid triglyceride, Docosadienoic acid triglyceride, Adrenic acid triglyceride, Ozbond acid triglyceride, Iwacic acid triglyceride, Docosahexaenoic acid triglyceride, Tetracrotonic acid pentaerythritol, Tetrapalmitoleic acid pentaerythritol, Tetrasabienoic acid penta Erythritol, Pentaerythritol monooleate, Pentaerythritol dioleate, Pentaerythritol trioleate, Pentaerythritol tetraoleate, Pentaerythritol tetraelainate, Pentaerythritol tetraboleate, Pentaerythritol tetralinoleate, Pentaerythritol dilinolenate, Trilinolene Pentaeri acid Lititol, pentaerythritol tetralinolenate, pentaerythritol tetrapinolenate, pentaerythritol tetraelestearate, pentaerythritol tetrastearic acid, pentaerythritol tetrabotheopentanoate, pentaerythritol tetragadelate, tetracosadienate penta Erythritol, Tetraicosatrienoic acid pentaerythritol, Tetraicosenic acid pentaerythritol, Tetraicosadienoic acid pentaerythritol, Tetraicosatrienoic acid pentaerythritol, Tetraicosatetraenoic acid pentaerythritol, Tetraicosapentaenoic acid pentaerythritol, Tetramede Pentaerythritol acid, pentaerythritol tetraarachidonic acid, tetraerucic acid pen Taerythritol, pentaerythritol tetradocosadienoate, pentaerythritol tetraadrenoate, pentaerythritol tetraozbond acid, pentaerythritol tetriwasate, pentaerythritol tetradocosahexaenoate, crotonic acid polyoxyethylene triglyceride, palmitoleic acid polyoxyethylene triglyceride, linoleic acid Polyoxyethylene triglyceride, linolenic acid polyoxyethylene triglyceride, oleic acid polyoxyethylene triglyceride, tetrapalmitoleic acid polyoxyethylene pentaerythritol, tetralinoleic acid polyoxyethylene pentaerythritol, tetralinolenic acid polyoxyethylene pentaerythritol, hexacrotonic acid poly Oxyethylene sorbit, Oxapalmitoleic acid polyoxyethylene sorbite trioleic acid polyoxyethylene sorbite, tetraoleic acid polyoxyethylene sorbitol, hexaoleic acid polyoxyethylene sorbitol, hexaelaidic acid polyoxyethylene sorbitol, tetralinoleic acid polyoxyethylene sorbitol, hexalinoleic acid Unsaturated monobasic acids and polyhydric alcohols such as polyoxyethylene sorbit, tetralinolenic acid polyoxyethylene sorbit, hexalinolenic acid polyoxyethylene sorbit, hexastearidonic acid polyoxyethylene sorbit, hexaeicosenoic acid polyoxyethylene sorbit Unsaturated fatty acid polyesters of

  For example, glyceryl mono-2-ethylcaproate, glyceryl di-2-ethylcaproate, glyceryl tri-2-ethylhexanoate, glyceryl monobehenate, glyceryl monocaprylate, glyceryl tricaprylate, glyceryl trilaurate, glyceryl tricaprate, triisostearic acid Glyceryl, glyceryl dibehenate, glyceryl tribehenate, glyceryl tribehenate, polyoxyethylene glyceryl monolaurate, polyoxyethylene glyceryl monomyristate, polyoxyethylene glyceryl monostearate, polyoxyethylene glyceryl monooleate, mono-2-ethylcapron Trimethylolpropane acid, trimethylolpropane di-2-ethylcaproate, trimethylolpropane tri-2-ethylcaproate Monolauric acid polyoxyethylene trimethylolpropane, monomyristic acid polyoxyethylene trimethylolpropane, monostearic acid polyoxyethylenetrimethylolpropane, monooleic acid polyoxyethylenetrimethylolpropane, monolinoleic acid polyoxyethylenetrimethylolpropane, mono Linolenic acid polyoxyethylene trimethylolpropane, polyoxyethylene sorbitan monostearate, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monooleate Esters, polyoxyethylene glyceryl monoisostearate, pentaerythris Tall mono laurate, pentaerythritol monomyristate, pentaerythritol monostearate, pentaerythritol monooleate, fatty acid monoesters of monobasic acids with polyhydric alcohols such as pentaerythritol mono linoleic acid esters.

In the fatty acid ester (c1), the epoxy-modified ester obtained by further modifying the ester of (3), (1) or (2) with an epoxy includes the above unsaturated fatty acid monoester, unsaturated fatty acid diester, or unsaturated fatty acid polyvalent ester. An epoxy-modified ester obtained by allowing a peracid such as m-chloroperbenzoic acid or dimethyloxirane to act on the ester to epoxidize the olefinic double bond contained in the unsaturated fatty acid ester is exemplified.
The fatty acid ester (c1) can be used alone or in combination of two or more.

The phosphate ester (c2) is an ester compound obtained by dehydration condensation of phosphoric acid and the above-mentioned tetravalent or lower alcohol having 22 or less carbon atoms.
For example, monomethyl phosphate, monoethyl phosphate, monopropyl phosphate, monobutyl phosphate, monohexyl phosphate, mono 2-ethylhexyl phosphate, monooctyl phosphate, monoapril phosphate, monopelargone phosphate, monocaprin phosphate, phosphorus Monoundecyl phosphate, mono-2-butyloctoctyl phosphate, monolauryl phosphate, monotridecyl phosphate, monomyristyl phosphate, monopentadecyl phosphate, monopalmityl phosphate, monoisocetyl phosphate, monoheptaden phosphate, monostearyl phosphate, phosphorus Monoisostearyl acid, monononadecyl phosphate, monoarachidyl phosphate, monooctyldodecyl phosphate, monohenecosan phosphate, monobehenyl phosphate, mono 2- (2-butoxyethoxy) ethyl phosphate, mono 2- (2 -Methoxye ) Ethyl and or phosphoric acid saturated monocarboxylic esters such as alkylene oxide adducts thereof;

  For example, phosphate unsaturation such as monopalmitoleyl phosphate, monoelasyl phosphate, monooleyl phosphate, monolinoleyl phosphate, monoelyl phosphate phosphate, monolinoleyl phosphate, monoercyl phosphate, or alkylene oxide adducts thereof Monoesters;

  For example, dimethyl phosphate, diethyl phosphate, dipropyl phosphate, dibutyl phosphate, dihexyl phosphate, di-2-ethylhexyl phosphate, diapril phosphate, dipelargone phosphate, dicaprin phosphate, diundecyl phosphate, di-2-phosphate Butyloctyl, dilauryl phosphate, ditridecyl phosphate, dimyristyl phosphate, dipentadecyl phosphate, dipalmityl phosphate, diisocetyl phosphate, diheptadene phosphate, distearyl phosphate, diisostearyl phosphate, dinonadecyl phosphate, diarachidyl phosphate Dioctyldodecyl phosphate, diheneicosane phosphate, dibehenyl phosphate, di-2- (2-butoxyethoxy) ethyl phosphate, di-2- (2-methoxyethoxy) ethyl phosphate, or alkylene oxide adducts thereof Phosphoric acid saturated di Ester;

  For example, phosphoric acid unsaturated diesters such as dipalmitoleyl phosphate, dielydyl phosphate, dioleyl phosphate, dilinoleyl phosphate, dielyl phosphate phosphate, dilinoleyl phosphate, dielsyl phosphate, or alkylene oxide adducts thereof ;

  For example, trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, trihexyl phosphate, tri-2-ethylhexyl phosphate, triapril phosphate, tripelargone phosphate, tricaprin phosphate, triundecyl phosphate, triphosphate phosphate 2-butyl octyl, trilauryl phosphate, tritridecyl phosphate, trimyristyl phosphate, tripentadecyl phosphate, tripalmityl phosphate, triisocetyl phosphate, triheptadene phosphate, tristearyl phosphate, triisostearyl phosphate, phosphorus Trinonadecyl acid phosphate, trialachidyl phosphate, trioctyldodecyl phosphate, triheneicosane phosphate, ditribehenyl phosphate, tri-2- (2-butoxyethoxy) ethyl phosphate, tri-2- (2-methoxyethoxy) ethyl phosphate, , Other phosphate saturated triesters such as alkylene oxide adducts thereof;

  For example, phosphate unsaturation such as tripalmitoleyl phosphate, trieriyl phosphate, trioleyl phosphate, trilinoleyl phosphate, trielyl phosphate phosphate, trilinoleyl phosphate, trielsyl phosphate, or their alkylene oxide adducts Triester;

  For example, for example, polyoxyethylene oleyl ether phosphate, polyoxyethylene lauryl ether phosphate, polyoxyethylene cetyl ether phosphate, polyoxyethylene octyl ether phosphate, polyoxyethylene decyl ether phosphate, etc. Polyoxyalkylene alkyl ether phosphate ester having 2 to 20 moles of addition of ethylene oxide (EO);

For example, polyoxyethylene oleyl phenyl ether phosphate, polyoxyethylene lauryl phenyl ether phosphate, polyoxyethylene cetyl phenyl ether phosphate, polyoxyethylene octyl phenyl ether phosphate, polyoxyethylene decylphenyl ether phosphate Examples thereof include polyoxyethylene alkylphenyl ether phosphates having 2 to 20 addition moles of ethylene oxide (EO) such as esters and polyoxyethylene ethyl phenyl ether phosphates.
The phosphate ester (c2) can be used alone or in combination of two or more.

The boric acid ester (c3) is an ester compound obtained by dehydration condensation between boric acid and the above-mentioned tetravalent or lower alcohol having 22 or less carbon atoms.
For example, methoxydiethylene glycol ether borate, methoxytriethylene glycol ether borate, methoxytetraethylene glycol ether borate, ethoxytriethylene glycol ether borate, ethoxydiethylene glycol ether borate, ethoxytetraethylene glycol ether borate Ester, propoxy triethylene glycol ether borate, triethylene glycol monobutyl ether borate, diethylene glycol monobutyl ether borate, butoxytetraethylene glycol ether borate, butoxytriethylene glycol ether borate, butoxytetraethylene glycol ether Borate ester Xypentoxydiethylene glycol ether borate, pentoxytriethylene glycol ether borate, 2-ethylhexyloxydiethylene glycol ether borate, diethylene glycol monopropyl ether ether borate, triethylene glycol monopropyl ether borate, polyethylene glycol mono Polyoxyalkylene alkyl ether borate esters having 2 to 20 moles of addition of ethylene oxide (EO) such as butyl ether borate ester, polyethylene glycol monopropyl ether borate ester, polyethylene glycol monobutyl ether borate ester;

  For example, dipropylene glycol monomethyl ether borate, dipropylene glycol monopropyl ether borate, tripropylene glycol monopropyl ether borate, dipropylene glycol monobutyl ether borate, dipropylene glycol monomethyl ether borate, tripropylene Propylene oxide (PO) such as propylene glycol monoethyl ether borate, tripropylene glycol monopropyl ether borate, tripropylene glycol monobutyl ether borate, polypropylene glycol monopropyl ether borate, polypropylene glycol monobutyl ether borate ) Polyoxyalkylene alkyl having 2 to 20 moles added Ether borate ester;

  For example, polyoxyalkylene alkyl ether borate esters having 2-20 addition moles of butylene oxide (BO) such as polybutylene glycol monopropyl ether borate ester and polybutylene glycol monobutyl ether borate ester;

For example, di (glycerin) borate monostearate, di (glycerin) borate sesquistearate, di (glycerin) borate monooleate, polyoxyethylene di (glycerin) borate monopalinate (EO addition mole number: 6 to 20), Examples include glycerin ether borate esters such as polyoxyethylene di (glycerin) borate monooleate (EO addition mole number: 6 to 20).
The borate ester (c3) can be used alone or in combination of two or more.

  The ester compound (C) preferably has a molecular weight (formula weight) of 200 to 2,000. When the molecular weight is in the above range, the compatibility with the polyurethane resin (A) is improved, so that the removability is improved by improving the transparency and cohesion, and the adherend is hardly contaminated.

  The ester compound (C) preferably has a surface tension of 20 mN / cm or more and less than 40 mN / cm. When the surface tension is in the above range, the compatibility with the polyol (a1-2) contained in the polyurethane resin (A) can be reduced, so that it becomes easy to orient on the adhesive surface of the adhesive film, and from room temperature to low temperature over a long period of time. It is possible to obtain stable wet spreadability while maintaining flexibility.

  It is preferable to contain 1-100 mass parts of ester compounds (C) with respect to 100 mass parts of polyurethane resins (A), and 5-50 mass parts is more preferable. When the ester compound (C) is in the above range, the adhesive layer can be sufficiently plasticized to improve flexibility, and further improve the maintenance of low adhesive strength in the microviscous region and the wet-spreading property of the pressure-sensitive adhesive film. be able to.

  Among these, in addition to industrial availability, the ester compound (C) is, for example, compatible with the polyurethane resin (A), wet spreadability, removability, and suppression of adherend contamination. Cetyl 2-ethylcaproate, isocetyl 2-ethylcaproate, stearyl 2-ethylcaproate, isopropyl myristate, isocetyl myristate, octyldodecyl myristate, methyl laurate, butyl laurate, hexyl laurate, hexyl dimethyloctanoate Decyl, methyl oleate, myristyl myristate, isopropyl palmitate, 2-ethylhexyl palmitate, methyl stearate, butyl stearate, 2-ethylhexyl stearate, stearyl stearate, isotridecyl stearate, isoprostearate , Cholesteryl isostearate, lauryl methacrylate, isopropyl oleate, butyl oleate, octyl oleate, octyldodecyl oleate, neopentyl glycol di-2-ethylcaproate, polyoxyethylene di-2-ethylcaproate, propylene dicaprylate Glycol, propylene glycol dicaprate, propylene glycol diisostearate, bis {2- (2-butoxyethoxy) ethyl adipate}, bis (2-butoxyethyl) adipate, diisodecyl adipate, bis (2-ethylhexyl) adipate, Neopentyl glycol di-2-ethylcaproate, oxyethylene di-2-ethylcaproate (EO addition mole number: 4 to 16), glyceryl tri-2-ethylcaproate, glyceryl monocaprylate Glyceryl tricaprylate, glyceryl monobehenate, glyceryl monobehenate, glyceryl tri-2-ethylcaproate, glyceryl trilaurate, glyceryl tricaprate, glyceryl triisostearate, 2-ethylcaproate polyoxyethylene triglyceride (EO addition moles: 2-16), polyoxyethylene bisphenol A laurate, glyceryl trioleate, trimethylolpropane tri2-ethylcaproate, triglyceride oleate, pentaerythritol monooleate, pentaerythritol monostearate, pentaerythritol tetrapalmitate Fatty acid esters such as tri-2-ethylhexyl phosphate, trioctyl phosphate, polyoxyethylene oleyl ether phosphate Ter (EO addition mole number: 2 to 16), polyoxyethylene lauryl ether phosphate ester (EO addition mole number: 2 to 16), polyoxyethylene octyl ether phosphate ester (EO addition mole number: 2 to 16), etc. Or triethylene glycol monopropyl ether borate, polyethylene glycol monobutyl ether borate (EO addition moles: 2 to 16), polyoxyethylene glycerine ether borate (EO addition moles: 2) -16) and the like.

<Ionic compound (D)>
Further, the ionic compound (D) will be described.
The pressure-sensitive adhesive of the present invention can further contain an ionic compound (D). In addition, components other than a polyurethane resin (A), the reactive compound (B) which has a functional group which can react with a hydroxyl group, and an ester compound (C) are called arbitrary components.
The ionic compound (D) is a liquid or solid ionic compound at normal temperature (25 ° C.). Examples of the ionic compound (D) include inorganic salts of alkali metals and organic salts of alkali metals. Examples of the ionic compound (D) include surfactants, ammonium chloride, aluminum chloride, copper chloride, ferrous chloride, ferric chloride, and ammonium sulfate. Among these, alkali metal salts, liquid ionic compounds, and solid ionic compounds are preferable, and alkali metal salts and liquid ionic compounds are more preferable.

Examples of the alkali metal salt include metal salts composed of lithium, sodium, and potassium. The alkali metal salt is composed of a cation moiety composed of Li ⁺ , Na ⁺ and K ⁺ and various anion moieties. According to the kind of anion part, it can be divided into an inorganic salt and an organic salt. Examples of the alkali metal inorganic salt include sodium chloride, potassium chloride, lithium chloride, lithium perchlorate (LiClO ₄ ), potassium chlorate, potassium nitrate, sodium nitrate, sodium carbonate, sodium thiocyanate, LiBr, LiI, LiBF _4. , LiPF ₆ , LiSCN and the like. From the viewpoints of conductivity and safety, sodium chloride, potassium chloride, lithium perchlorate and the like are preferable.

Examples of the alkali metal organic salt include sodium acetate, sodium alginate, sodium lignin sulfonate, sodium toluenesulfonate, LiCF ₃ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N, Li (CF ₃ SO ₂ ) IN, Li (C ₂ F ₅ SO ₂ ) ₂ N, Li (C ₂ F ₅ SO ₂ ) IN, Li (CF ₃ SO ₂ ) ₃ C and the like can be mentioned, and LiCF ₃ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N Li (CF ₃ SO ₂ ) IN, Li (C ₂ F ₅ SO ₂ ) ₂ N, Li (C ₂ F ₅ SO ₂ ) IN, Li (CF ₃ SO ₂ ) ₃ C and the like are preferable, and Li (CF _{3 SO 2) 2 N, Li (} CF 3 SO 2) iN, Li (C 2 F 5 SO 2) 2 N, Li (C 2 F 5 SO 2) fluorine-containing lithium imide salts such as iN, in particular (perfluoroalkyl sulfonyl ) Imidolithium salt and the like.

  A liquid ionic compound is a compound that exhibits liquid properties at room temperature, and is composed of a cation component and an anion component. Examples of the cation component include a pyridinium cation, a piperidinium cation, a pyrrolidinium cation, a cation having a pyrroline skeleton, a cation having a pyrrole skeleton, an imidazolium cation, a tetrahydropyrimidinium cation, a dihydropyrimidinium cation, and a pyrazolium. Examples thereof include a cation, a pyrazolinium cation, a tetraalkylammonium cation, a trialkylsulfonium cation, and a tetraalkylphosphonium cation.

The anion component only needs to be able to generate a liquid ionic compound. For example, Cl ⁻ , Br ⁻ , I ⁻ , AlCl ₄ ⁻ , Al ₂ Cl ₇ ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , ClO ₄ ⁻ , NO ₃ ⁻ , CH ₃ COO ⁻ , CF ₃ COO ⁻ , CH ₃ SO ₃ ⁻ , CF ₃ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) ₃ C ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , NbF ₆ ⁻ , TaF ₆ ⁻ , F (HF) _n ⁻ , (CN) ₂ N ⁻ , C ₄ F ₉ SO ₃ ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , C ₃ F ₇ COO ⁻ , ( CF ₃ SO ₂ ) (CF ₃ CO) N- ^{and the} like. Among these, an anionic component containing a fluorine atom is preferable because an ionic compound having a low melting point can be obtained.

  Examples of the liquid ionic compound include 1-butylpyridinium tetrafluoroborate, 1-butylpyridinium hexafluorophosphate, 1-butyl-3-methylpyridinium tetrafluoroborate, 1-butyl-3-methylpyridinium trifluoromethanesulfonate, 1 -Butyl-3-methylpyridinium bis (trifluoromethanesulfonyl) imide, 1-butyl-3-methylpyridinium bis (pentafluoroethanesulfonyl) imide, 1-hexylpyridinium tetrafluoroborate, 2-methyl-1-pyrrolinetetrafluoro Borate, 1-ethyl-2-phenylindole tetrafluoroborate, 1,2-dimethylindole tetrafluoroborate, 1-ethylcarbazole tetrafluoroborate, 1-e Ru-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium acetate, 1-ethyl-3-methylimidazolium trifluoroacetate, 1-ethyl-3-methylimidazolium heptafluorobutyrate, 1 -Ethyl-3-methylimidazolium trifluoromethanesulfonate, 1-ethyl-3-methylimidazolium perfluorobutanesulfonate, 1-ethyl-3-methylimidazolium dicyanamide, 1-ethyl-3-methylimidazolium bis (trifluoromethane Sulfonyl) imide, 1-ethyl-3-methylimidazolium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-3-methylimidazolium tris (trifluoromethanesulfonyl) methide, 1-butyl- -Methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium trifluoroacetate, 1-butyl-3-methylimidazolium heptafluorobutyrate, 1- Butyl-3-methylimidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium perfluorobutanesulfonate, 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, 1-hexyl-3-methylimidazole 1-hexyl-3-methylimidazolium chloride, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium hexafluorophosphine 1-hexyl-3-methylimidazolium trifluoromethanesulfonate, 1-octyl-3-methylimidazolium tetrafluoroborate, 1-octyl-3-methylimidazolium hexafluorophosphate, 1-hexyl-2,3 -Dimethylimidazolium tetrafluoroborate, 1,2-dimethyl-3-propylimidazolium bis (trifluoromethanesulfonyl) imide, 1-methylpyrazolium tetrafluoroborate, 3-methylpyrazolium tetrafluoroborate, tetrahexylammonium Bis (trifluoromethanesulfonyl) imide, diallyldimethylammonium tetrafluoroborate, diallyldimethylammonium trifluoromethanesulfonate, diallyldimethylammonium vinyl (Trifluoromethanesulfonyl) imide, diallyldimethylammonium bis (pentafluoroethanesulfonyl) imide, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium tetrafluoroborate, N, N-diethyl-N- Methyl-N- (2-methoxyethyl) ammonium trifluoromethanesulfonate, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N- Methyl-N- (2-methoxyethyl) ammonium bis (pentafluoroethanesulfonyl) imide, glycidyltrimethylammonium trifluoromethanesulfonate, glycidyltrimethylammonium bis (trifluoromethanesulfonyl) Imide, glycidyltrimethylammonium bis (pentafluoroethanesulfonyl) imide, 1-butylpyridinium (trifluoromethanesulfonyl) trifluoroacetamide, 1-butyl-3-methylpyridinium (trifluoromethanesulfonyl) trifluoroacetamide, 1-ethyl-3- Methylimidazolium (trifluoromethanesulfonyl) trifluoroacetamide, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium (trifluoromethanesulfonyl) trifluoroacetamide, diallyldimethylammonium (trifluoromethanesulfonyl) trifluoro Acetamide, glycidyltrimethylammonium (trifluoromethanesulfonyl) trifluoroacetamide, N, N-dimethyl Ru-N-ethyl-N-propylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-butylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl- N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-heptylammonium bis (Trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-nonylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N, N-dipropylammonium bis (trifluoromethanesulfonyl) imide, N, -Dimethyl-N-propyl-N-butylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-propyl -N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-propyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-butyl-N-hexylammonium bis (Trifluoromethanesulfonyl) imide, N, N-dimethyl-N-butyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-pentyl-N-hexylammonium bis (trifluorome Sulfonyl) imide, N, N-dimethyl-N, N-dihexylammonium bis (trifluoromethanesulfonyl) imide, trimethylheptylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N-propylammonium Bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N-heptylammonium bis (trifluoromethanesulfonyl) Imido, N, N-diethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, triethylpropylammonium bis (trifluoromethanesulfonyl) imide, triethyl Pentylammonium bis (trifluoromethanesulfonyl) imide, triethylheptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl-N-methyl-N-ethylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl-N -Methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl-N-butyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl-N, N-dihexylammonium Bis (trifluoromethanesulfonyl) imide, N, N-dibutyl-N-methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dibutyl-N-methyl-N-hex Ruammonium bis (trifluoromethanesulfonyl) imide, trioctylmethylammonium bis (trifluoromethanesulfonyl) imide, N-methyl-N-ethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, 1-octyl- 4-methylpyridinium bis (trifluoromethanesulfonyl) imide and the like can be mentioned.

It is preferable to contain 0.001-20 mass parts of ionic compounds (D) with respect to 100 mass parts of polyurethane resins (A). When the amount is within the above range, a sufficient antistatic function is exhibited, and whitening or bleeding out of the adhesive layer can be suppressed.
The ionic compound (D) can be used alone or in combination of two or more.

<Hydrolysis inhibitor (E)>
The pressure-sensitive adhesive of the present invention may further contain a hydrolysis inhibitor.
When the hydrolysis inhibitor (E) is contained, the carboxyl group generated when the polyurethane resin (A) undergoes hydrolysis in a high temperature and high humidity atmosphere can be blocked.
The hydrolysis inhibitor (E) is preferably, for example, a carbodiimide, isocyanate, oxazoline, or epoxy system, and a carbodiimide is more preferable because hydrolysis can be more effectively suppressed.
The hydrolysis inhibitor (E) is preferably contained in an amount of 0.01 to 2.0 parts by weight, more preferably 0.02 to 1.5 parts by weight, with respect to 100 parts by weight of the polyurethane resin (A). 05-1.0 mass part is further more preferable.
Hydrolysis inhibitors can be used alone or in combination of two or more.

  Note that. The hydrolysis inhibitor (E) is preferably used in combination with the other component (P) described below, and particularly preferably used in combination with an antioxidant. Specifically, a combination of a carbodiimide-based hydrolysis inhibitor and a phenol-based antioxidant is preferable, and a combination of a carbodiimide-based hydrolysis inhibitor, a phenol-based antioxidant, and a phosphorus-based antioxidant is more preferable. By using a hydrolysis inhibitor and an antioxidant in combination, hydrolysis resistance can be further improved, and decomposition and thermal yellowing of the hydrolysis inhibitor itself can be suppressed.

A carbodiimide-based hydrolysis inhibitor is a compound having a carbodiimide group.
Examples of the monocarbodiimide compound include dicyclohexylcarbodiimide, diisopropylcarbodiimide, dimethylcarbodiimide, diisobutylcarbodiimide, dioctylcarbodiimide, diphenylcarbodiimide, naphthylcarbodiimide, and the like.
The polycarbodiimide compound is a high molecular weight polycarbodiimide produced by decarboxylation condensation reaction of diisocyanate in the presence of a carbodiimidization catalyst.
Examples of the polycarbodiimide compound include 4,4′-diphenylmethane diisocyanate, 3,3′-dimethoxy-4,4′-diphenylmethane diisocyanate, 3,3′-dimethyl-4,4′-diphenylmethane diisocyanate, and 4,4′-diphenyl ether. Diisocyanate, 3,3′-dimethyl-4,4′-diphenyl ether diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1-methoxyphenyl-2,4-diisocyanate, isophorone diisocyanate, 4,4 Examples include '-dicyclohexylmethane diisocyanate and tetramethylxylylene diisocyanate. The carbodiimidization catalyst was 1-phenyl-2-phospholene-1-oxide, 3-methyl-2-phospholene-1-oxide, 1-ethyl-3-methyl-2-phospholene-1-oxide, 1-ethyl. Phospholene oxides such as 2-phospholene-1-oxide or their 3-phospholene isomers.

<Other components (P)>
In one embodiment of the pressure-sensitive adhesive of the present invention, other components (P) are appropriately added to the pressure-sensitive adhesive in addition to the essential components as long as the effects of the present invention are not impaired. Is also possible.
Other components (P) are, for example, polymerization curing shrinkage reduction, thermal expansion coefficient reduction, dimensional stability improvement, elastic modulus improvement, redox suppression, viscosity adjustment, thermal conductivity improvement, strength improvement, toughness improvement, and coloring From the viewpoint of improvement, organic or inorganic additives and fillers can be blended. The filler is composed of polymers, ceramics, metals, metal oxides, metal salts, dyes and pigments, and the like. The shape of the filler is preferably, for example, particulate or fibrous. Additives include antioxidants, flame retardants, storage stabilizers, antioxidants, UV absorbers, thixotropy imparting agents, dispersion stabilizers, fluidity imparting agents, thickeners, humectants, pH adjusters. Leveling agents, antifoaming agents and the like can be mentioned, and the method of addition can be dissolved, semi-dissolved or micro-dispersed in the pressure-sensitive adhesive as a polymer blend or a polymer alloy in addition to the usual mixing.

<Pressure sensitive adhesive>
The pressure-sensitive adhesive is also referred to as a pressure-sensitive adhesive, and is an adhesive that adheres by simply applying pressure at room temperature for a short time because it has a viscous property regardless of the solidification of the adhesive.
The pressure-sensitive adhesive of the present invention is a pressure-sensitive adhesive containing a polyurethane resin (A), a reactive compound (B) having a functional group capable of reacting with a hydroxyl group, and an ester compound (C).
The monomer unit constituting the polyurethane resin (A) contains a polyol (a1) unit and a polyisocyanate (a2) unit. The polyurethane resin (A) has a surface tension of 20 mN / cm or more and less than 40 mN / cm. A polyol (a1-1) containing a certain polyol (a1-1) and a polyol (a1-2) having a surface tension of 40 mN / cm or more and less than 60 mN / cm, and a reaction product of the polyisocyanate (a2), The number average molecular weight of the polyol (a1-1) is 2,000 to 10,000, and the number average molecular weight of the polyol (a1-2) is 400 to 4,000, and the polyol (a1-1) Is a pressure-sensitive adhesive having a number average molecular weight equal to or greater than that of the polyol (a1-2).
If necessary, an ionic compound (D), a hydrolysis inhibitor (E) or other component (P) is appropriately mixed.
Moreover, an ionic compound (D), a hydrolysis inhibitor (E), or another component (P) may be called arbitrary components.

  It is preferable that the viscosity of the pressure-sensitive adhesive of the present invention is appropriately adjusted according to the usage form. The pressure-sensitive adhesive of the present invention can use the following organic solvents in order to adjust the viscosity. In particular, organic solvents include alcohol solvents such as methanol, ethanol and isopropyl alcohol, ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as methyl acetate, ethyl acetate and butyl acetate, cyclohexane, toluene and xylene. It is preferable to use various organic solvents such as hydrocarbon solvents such as water, water, and mixtures thereof. However, care should be taken when using a solvent having active hydrogen that may react with the reactive compound (B), such as an alcohol solvent. Also, the viscosity can be reduced by heating the pressure sensitive adhesive without using an additional solvent.

  The viscosity of the pressure-sensitive adhesive of the present invention is preferably 1,000 to 10,000 mPa · s when measured with a B-type viscometer at 25 ° C. from the viewpoint of forming an adhesive layer. 8,000 to 8,000 mPa · s is more preferable. When the viscosity is less than 10,000 mPa · s, it becomes easy to form an adhesive layer having a thickness of 0.5 to 300 μm, and optical characteristics such as transmittance can be improved. Moreover, when the viscosity is 1,000 mPa · s or more, it becomes easy to control the thickness of the adhesive layer. In this embodiment, the film thickness, viscosity, or nonvolatile content concentration of the adhesive layer is appropriately set according to the use of the laminate.

<Method for producing pressure-sensitive adhesive>
As a method for producing a pressure-sensitive adhesive, first, after producing a polyurethane resin (A), an optional component is mixed, and a reactive compound (B) having a functional group capable of reacting with the hydroxyl group is contained. It can be a pressure sensitive adhesive.
The pressure-sensitive adhesive is produced by a first step of producing a polyurethane resin (A) by reacting a polyol (a1) and a polyisocyanate (a2), and a second step of mixing the polyurethane resin (A) and an optional component. The reactive compound (B) having a functional group capable of reacting with a hydroxyl group is mixed with the mixture obtained in the second step. In addition, when not mixing arbitrary components, the said 2nd process can be skipped.

<Method for producing polyurethane resin (A)>
The first step for producing the polyurethane resin (A) will be described.
The urethanization reaction for producing the polyurethane resin (A) by reacting the polyol (a1) and the polyisocyanate (a2) can be carried out in various ways, but is roughly classified into the following two methods.
[I] A method in which polyol (a1), polyisocyanate (a2), an organic solvent, and a catalyst are all charged and reacted.
[Ii] A method in which a polyol (a1), a catalyst and an organic solvent are charged into a flask, a polyisocyanate (a2) is dropped, and then a catalyst is additionally added as necessary.
[Ii] is preferable when the reaction is precisely controlled. The reaction temperature is preferably 120 ° C. or lower, and more preferably 50 to 100 ° C. When the reaction is carried out at a predetermined temperature, the reaction rate can be easily controlled and a polyurethane resin (A) having a predetermined weight average molecular weight and structure can be easily obtained. The urethanization reaction may be performed without a catalyst, but it is preferably performed in the presence of a catalyst at 80 to 100 ° C. for 1 to 20 hours.

The mixing ratio of the polyol (a1) and the polyisocyanate (a2) is that the polyurethane resin (A) needs to have at least one hydroxyl group, so the polyisocyanate is used with respect to 1 mol of the hydroxyl group in the polyol (a1). It is necessary that the number of isocyanate groups in (a2) be less than 1 mole, preferably 0.5 to 0.95 mole, and more preferably 0.6 to 0.9 mole. Within this range, the reactivity with the reactive compound (B) is improved, an adhesive layer having high transparency can be easily obtained, the adhesion to the curved surface portion is improved, and adherend contamination during peeling can be suppressed. .
The end point of the synthesis reaction is determined by measurement of isocyanate content by titration (mass%) or disappearance of characteristic absorption based on isocyanate group (NCO) by infrared absorption spectrum (IR) measurement. In addition, the detail of the measuring method of isocyanate content by titration is described in an Example.

  The said catalyst can be used at the time of manufacture of a polyurethane resin (A). The reaction between an isocyanate group and a hydroxyl group is naturally fast, but in the presence of an organometallic compound catalyst, the reaction is further promoted and may be difficult to control. At this time, when a chelate compound is added, a chelate is formed with the organometallic compound, the catalytic ability is adjusted, and the reaction is easily controlled.

  Examples of the chelate compound include acetylacetone, dimethylglyoxime, oxine, dithizone, polyaminooxyacids such as ethylenediaminetetraacetic acid (also known as EDTA), oxycarboxylic acids such as citric acid, and condensed phosphoric acid. Among these, acetylacetone is preferable because it is soluble in an organic solvent, has volatility, and can be easily removed if necessary.

  Since the chelate compound remains in the pressure-sensitive adhesive, the reaction rate can be adjusted by acting on the reaction between the polyurethane resin (A) and the reactive compound (B). An excellent pressure-sensitive adhesive having an excellent life (also referred to as pot life) can be obtained.

An organic solvent can be used for producing the polyurethane resin (A). Reaction control is facilitated by using an organic solvent. Examples of the organic solvent include alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, and n-butyl alcohol, acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl isopropyl ketone, methyl-n-butyl ketone, Methyl isobutyl ketone, methyl-n-amyl ketone, methyl isoamyl ketone, diethyl ketone, ethyl-n-propyl ketone, ethyl isopropyl ketone, ethyl-n-butyl ketone, ethyl isobutyl ketone, di-n-propyl ketone, diisobutyl ketone, cyclohexanone, Ketones such as methylcyclohexanone and isophorone, methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, hexyl acetate, acetic acid Esters such as cutyl, methyl lactate, propyl lactate, butyl lactate, ethylene glycol, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, ethylene glycol dimethyl ether , Ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene Glycol and glycol ethers such as recall monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dipropyl ether, tripropylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, Diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol mono Glycol acetates such as methyl ether acetate, saturated hydrocarbons such as n-hexane, isohexane, n-nonane, isononane, dodecane and isododecane, unsaturated hydrocarbons such as 1-hexene, 1-heptene and 1-octene, Cyclic saturated hydrocarbons such as cyclohexane, cycloheptane, cyclooctane, cyclodecane and decalin, and cyclic unsaturated hydrocarbons such as cyclohexene, cycloheptene, cyclooctene, 1,1,3,5,7-cyclooctatetraene and cyclododecene , Aromatic hydrocarbons such as benzene, toluene, xylene and the like, dioxane, acetonitrile, tetrahydrofuran, diglyme, dimethyl sulfoxide, N-methylpyrrolidone, dimethylformamide and the like.
Among these, ethyl acetate, toluene, and methyl ethyl ketone are preferable in terms of the solubility of the polyurethane resin (A) and the boiling point of the solvent.

What is necessary is just to determine the compounding quantity of an organic solvent suitably considering the composition of a polyurethane resin (A), a viscosity, or a non volatile matter density | concentration. 40-99 mass% is preferable and, as for the non volatile matter density | concentration other than the organic solvent at the time of a polyurethane resin (A) synthesis | combination, 50-95 mass% is more preferable. When the concentration is within a predetermined range, the reactivity is improved.
The organic solvent can be used alone or in combination of two or more.

The second step will be described.
The pressure-sensitive adhesive of the present invention is obtained by blending an ester compound (C) and an optional component in a polyurethane resin (A), and mixing them with a mixer such as a Henschel mixer, a disper, an attritor, a high speed mixer, or a homomixer. A mixture of polyurethane resin (A) can be produced. In mixing, an organic solvent can be used in combination as appropriate.

The third step will be described.
The pressure-sensitive adhesive of the present invention is further mixed with the reactive compound (B) after the second step and mixed with a mixer such as a Henschel mixer, a disper, an attritor, a high speed mixer, or a homomixer. can do. During mixing, if necessary, bubbles and bubbles contained in the pressure-sensitive adhesive can be removed by vacuum degassing, and unexpected foreign matters can be removed by filtration or the like.
Moreover, the reaction between the hydroxyl group contained in the polyurethane resin (A) and the reactive functional group in the reactive compound (B) may be at any timing after mixing. For example, the reaction does not proceed immediately after mixing (or only part of the reaction proceeds), and after applying a pressure-sensitive adhesive to the substrate, it reacts during heating and drying to form a crosslinked coating and adhere You may express performance. Also, the timing of mixing is not particularly limited, and after applying one of the mixture of the polyurethane resin (A) and the reactive compound (B) to the surface of the base material, the other is separately applied, and at the time of heating and drying. The reaction may be allowed to proceed. Also, after each of the mixture of the polyurethane resin (A) and the reactive compound (B) is applied to separate substrate surfaces, the coated surfaces are bonded together, and then heated and dried to advance the reaction. Good. Preferably, a pressure-sensitive adhesive, which is a mixture of the polyurethane resin (A) and the reactive compound (B), is applied onto a substrate, and is crosslinked and cured by heating to form an adhesive layer. At this time, the surface of the adhesive layer has removable tackiness.

<Adhesive film>
The adhesive film of the present invention (also referred to as a pressure-sensitive adhesive film) is obtained by forming an adhesive layer composed of the above-mentioned pressure-sensitive adhesive on a base material (G) described later, and having a film-like substrate having a surface peel-treated. A material (also referred to as a release liner) may be laminated.
When manufacturing an adhesive film, after applying a pressure-sensitive adhesive to a substrate described later by an appropriate method according to a conventional method, the pressure-sensitive adhesive contains a liquid medium such as an organic solvent or water. When the liquid medium is removed by a method such as heating, or when the pressure-sensitive adhesive does not contain a liquid medium that should be volatilized, the molten adhesive layer is cooled and solidified, An adhesive layer can be formed. For example, a pressure-sensitive adhesive is applied to the release treatment surface of the release liner, dried, and a method of creating a substrate by pasting it together, or a pressure-sensitive adhesive is directly applied to a substrate other than the release liner, and dried. There is a method in which the release treatment surface of the release liner is bonded to the surface of the adhesive layer.

  The method for applying the pressure sensitive adhesive is not particularly limited. For example, various well-known methods such as Mayer bar, applicator, brush, spray, roller, gravure coater, die coater, kiss coater, lip coater, comma coater, blade coater, knife coater, reverse coater, spin coater, dip coater, etc. Can be applied. Moreover, it can select without particular restriction | limiting also about forms, such as thin film coating or thick film coating.

  When using the pressure sensitive adhesive of this invention and forming an adhesive layer, 0.5-300 micrometers is preferable and, as for the film thickness of an adhesive layer, 1-100 micrometers is more preferable. When the film thickness is in the above range, the adhesive film can be used as a protective film to obtain a sufficient adhesive force.

  The basic laminated structure of the adhesive film is a single-sided adhesive film such as a substrate / adhesive layer / release liner, or a double-sided adhesive film such as a release liner / adhesive layer / substrate / adhesive layer / release liner. Thus, the laminated body laminated | stacked on the release liner is called adhesive film. At the time of use, the release liner is peeled off and the adhesive layer is attached to the adherend. The pressure-sensitive adhesive is not only adhesive when the adhesive layer touches the adherend when it is attached, but also an adhesive other than the pressure-sensitive adhesive (hereinafter simply referred to as an adhesive). Unlike sticking, it is necessary to have a cohesive force for maintaining the sticking state while having a tack and appropriate hardness without being completely solidified during sticking. The cohesive force greatly depends on the molecular weight and crosslink density. Thus, the laminated body laminated | stacked on the structure of a base material / adhesion layer / adhered body is called sticking laminated body. When the sticking laminate is used for optical purposes, it is called an optical laminate. In the case of an electronic member, it is called an electronic laminate.

The adhesive film using the pressure-sensitive adhesive of the present invention is preferably used for surface protection film applications such as optical members and electronic members, and the pressure-sensitive adhesive contains two or more substrates (G) (of the substrate An adhesive layer is formed by bonding a base substrate of an adhesive film and a substrate (referred to as an adherend) to which the other substrate is bonded. The substrate may be a wood, a metal plate, a plastic plate, a film-like substrate, a glass plate, a paper processed product, etc., but when used for an optical member, since it needs transparency, a plastic plate, It is necessary to comprise a highly transparent material such as a film substrate or a glass plate. However, in applications that do not require transparency such as electronic members, if a transparent film or a transparent glass plate is used as one substrate, the other substrate is not a transparent substrate, for example, wood, A substrate made of a material such as a metal plate, a plastic plate, or a paper processed product can also be used.
At the time of bonding, as described above, an adhesive film is prepared, and the release liner is peeled off and attached to the adherend, or a pressure sensitive adhesive is directly injected between the two base materials and attached. In either case, it is not limited, but it is preferable in terms of “removability” to reattach the adhesive laminate in which the film is attached to a substrate such as a glass surface, which is attached via an adhesive film. .

  As described above, examples of the release liner include those obtained by subjecting the surface of a film-like substrate such as cellophane, various plastic films, and paper to a release treatment. Moreover, as a film-form base material, the thing of a single layer may be used, and the thing in the multilayer state formed by laminating | stacking a some base material can also be used. Moreover, when a transparent film (H) is used, the said laminated body can be used suitably for an optical use. From the viewpoint of obtaining good optical properties, the above laminate is called an optical laminate, and the transparent film (H) used is, for example, transparency, mechanical strength, thermal stability, moisture barrier properties, and isotropic properties. It is preferable that it is comprised from the thermoplastic resin which is excellent in optical characteristics, such as.

  Such various transparent films (H) are also referred to as various plastic films or plastic sheets. For example, polyvinyl alcohol film (also referred to as PVA film), polytriacetyl cellulose film (also referred to as TAC film), polypropylene film (also referred to as PP film), polyethylene film (also referred to as PE film), polycycloolefin film (also referred to as COP film) ), Polyolefin-based resin films such as ethylene-vinyl acetate copolymer film (also referred to as EVA film), polyester-based resins such as polyethylene terephthalate film (also referred to as PET film) and polybutylene terephthalate film (also referred to as PBT film). Film, polycarbonate resin film (also called PC film), polynorbornene resin film, polyarylate resin film, poly Crylic acid ester resin film, polyphenylene sulfide resin film (also called PPS film), polystyrene resin film (also called PST film), polyamide resin film (also called PA film), polyimide resin film ( Also referred to as a PI film), oxirane resin films, and the like. Among these substrates, it is particularly preferable to use a sheet-like substrate such as a PVA film, a TAC film, a COP film, a polyester resin film, or a PC film as the transparent film (H).

In addition, the transparent film (H) has a surface with physical treatment such as corona discharge, plasma treatment, flame treatment, etc., chemical treatment that modifies the film surface with acid or alkali, etc. Films with a substantial increase in surface area of the substrate, or metal oxides such as silicon, aluminum, magnesium, calcium, potassium, tin, sodium, boron, titanium, lead, zirconium, yttrium on the surface, or non-metallic inorganic oxides For the pressure-sensitive adhesive, such as a plastic film on which is vapor-deposited, one that has been subjected to an easy adhesion treatment or one that has been provided with functionality for each application can be suitably used.
When the transparent film (H) is used as a protective film, the opposite surface where the adhesive layer is not formed is subjected to a release treatment by adding a fatty acid amide, polyethyleneimine, a long-chain alkyl-based additive, etc. A coating layer made of any appropriate release agent such as a system, a long chain alkyl system, or a fluorine system can be provided.

  Moreover, in this invention, it is set as the optical film (I) by which the adhesive layer which consists of a pressure-sensitive adhesive agent was formed on the said transparent film using the transparent film (H) as a base material (G) for the purpose of optical use. Is also possible. Here, as the optical film (I), the transparent film (H) can be used as an optical film as it is, and the transparent film (H) itself having a special function is used. Is also possible. Here, the special function is intended to have optical functions such as light transmission light diffusion, light collection, refraction, scattering, and haze. These transparent films (H) can be used alone or in combination of several kinds when used as the optical film (I). In the present invention, an adhesive film can be prepared by forming an adhesive layer made of the pressure-sensitive adhesive on at least one surface of the optical film (I), and laminated on a liquid crystal cell or the like. It can also be used for applications.

  When the optical laminate of the present invention is used as a surface protection film, the transparent film (H) is used as the substrate (G), and the adhesive layer and glass of the adhesive film formed from the pressure-sensitive adhesive of the present invention are sequentially formed. It is a laminated one. Here, the transparent film (H) is preferably a polyester resin film. A glass plate is preferably used as the substrate used as the adherend.

  The thickness of the transparent film (H) used for the surface protective film can be set to any thickness depending on the application. In order to fully express the effect of the pressure-sensitive adhesive of the present application, the thickness is preferably 5 μm to 300 μm, more preferably 15 μm to 150 μm.

  The adhesive film of the present invention preferably has high transparency when used as a protective film. Due to the high transparency of the surface protective film, it is possible to accurately inspect the surface of the optical member or the electronic member while it is adhered. The surface protective film of the present invention has a haze of preferably 5% or less, more preferably 2% or less. The details of the haze measurement are described in the examples.

  Further, the surface tension of the adhesive surface of the adhesive film is preferably 35 mN / cm or more and less than 40 mN / cm. When the surface tension is in the above range, it becomes possible to show the adhesiveness of the microviscous region to a highly polar adherend such as a glass plate (40 mN / cm or more and less than 60 mN / cm), and re-peelability. improves.

  The adhesive film of the present invention has been described by taking a polyester resin film as an example of the transparent film (H). However, the present invention is not limited to polyester resin films, and it is easy to construct a laminate that can be suitably used for optical applications in other embodiments using other transparent films (H) and other various substrates. Should be understood. For example, it can be preferably used for various electronic parts-related members such as liquid crystal displays, plasma displays, touch panels, electrode peripheral members, glass members such as surface protection films, building materials and vehicle window glass, and plastics such as polyolefin, ABS, and polyacryl. It can also be used for metal such as cardboard, wood, plywood, stainless steel, and aluminum.

  Specific examples of the present invention will be described below together with comparative examples, but the present invention is not limited to the following examples. In the following examples and comparative examples, “parts” and “%” represent “parts by mass” and “% by mass”, respectively, unless otherwise specified.

<Synthesis of polyurethane resin>
(Synthesis Example 1)
The following monomers {polyol (a1), polyisocyanate (a2)}, catalyst are added to a polymerization tank and a dropping device of a polymerization reactor equipped with a polymerization tank, a stirrer, a thermometer, a reflux condenser, a dropping device, and a nitrogen introducing tube. The organic solvent was charged in the following ratios.

[Polymerization tank]
FF3320 (a1-1) 88.08 parts PEG600 (a1-2) 7.34 parts Toluene (organic solvent) 16.84 parts DBU (catalyst) 0.0004 parts [dropping device]
HDI (a2) 4.58 parts Toluene (organic solvent) 29.96 parts

After replacing the air in the polymerization tank with nitrogen gas, the temperature was raised to 85 ° C. with stirring in a nitrogen atmosphere, and the mixture containing the above HDI (a2) and organic solvent was added from the dropping device over 1 hour. The reaction was started dropwise. The reaction was continued for 2 hours with further stirring. Then, after confirming that the characteristic absorption (2,270 cm ⁻¹ ) based on NCO in the IR chart has disappeared, 51.96 parts of ethyl acetate was added to adjust the nonvolatile content concentration (NV) to 50%. The reaction was terminated by cooling to ° C. This polyurethane resin (A) solution is colorless and transparent in appearance, solution viscosity (Vis) 3,800 mPa · s (25 ° C.), weight average molecular weight (Mw) 137,000, hydroxyl value (OHV) 32.9 mgKOH / g and surface tension of 35.8 mN / cm.

(Synthesis Examples 2 to 25)
Polyol (a1), polyisocyanate (a2), toluene (organic solvent), and catalyst are all charged into the polymerization tank, and polyisocyanate (a2) and toluene (organic solvent) are charged into the dropping device. The polyurethane resins of Synthesis Examples 2 to 25 were synthesized in the same manner as in Synthesis Example 1 except for the above changes. The compound used as a monomer described in Table 1 represents the total value (parts) of the amount charged to the polymerization tank and the amount charged to the dropping device.
However, in Synthesis Example 17, polyisocyanate (a2) was changed to IPDI. In Synthesis Example 18, polyisocyanate (a2) was changed to TDI. In Synthesis Example 23, the organic solvent in the polymerization tank was changed to ethyl acetate. In Synthesis Example 24, all organic solvents were changed to ethyl acetate. In Synthesis Example 25, the catalyst was changed to dioctyltin dilaurate, and all the organic solvents for dilution were changed to acetylacetone.

  The solution appearance (25 ° C.), nonvolatile concentration (NV), solution viscosity (Vis), weight average molecular weight (Mw), and hydroxyl value (OHV) of the obtained polyurethane resin solution were determined according to the methods described below, and the results were obtained. It is shown in Table 1. Moreover, it described also about the measuring method of acid value (AV), residual amount (%) of isocyanate group (NCO), and glass transition temperature (Tg).

<< Non-volatile content (NV) >>
About 1 g of the obtained polyurethane urea resin solution was weighed into a metal container, dried in an oven at 150 ° C. for 20 minutes, cooled to 25 ° C., and then the residue was weighed to calculate the residual rate. It was set as a partial concentration (solid content) (unit:%).

<< Solution appearance >>
The appearance of the obtained polyurethane resin solution was visually observed under the condition of 25 ° C. It is good if it is colorless and transparent.

<< Solution viscosity (Vis) >>
The solution of the obtained polyurethane resin was measured at 25 ° C. with a B-type viscometer (TV-22 manufactured by Toki Sangyo Co., Ltd.) under the conditions of rotor No. 3, rotation speed 0.5 to 100 rpm, and rotation for 1 minute. (MPa · s).

《Average molecular weight》
For the measurement of the number average molecular weight (Mn) and the weight average molecular weight (Mw), GPC (gel permeation chromatography) manufactured by Showa Denko KK was used. The determination of the number average molecular weight (Mn) and the weight average molecular weight (Mw) was a conversion value of polystyrene as a standard substance.
Device name: Showa Denko GPC (Gel Permeation Chromatography) “Shodex GPC System-21”
Column: Tosoh GMHXL: 4 Tosoh HXL-H: 1 In series.
Mobile phase solvent: Tetrahydrofuran (THF)
Flow rate: 1.0 ml / min Column temperature: 40 ° C

<< Surface tension (σ) >>
Calculated from the above general formula [3]. However, from the composition ratio (mass ratio) shown in Table 1, the molar volume ratio and the paracoll ratio were calculated, and then the molar volume and paracor of the smallest unit (unit) were calculated to calculate the surface tension. The surface tension of a pressure sensitive adhesive described later was calculated in the same manner.

<< Hydroxyl value (OHV) >>
About 1 g of a sample was accurately weighed in a stoppered Erlenmeyer flask and dissolved by adding 100 ml of a toluene / ethanol (volume ratio: toluene / ethanol = 2/1) mixed solution. Next, 5 ml of an acetylating agent (a solution in which 25 g of acetic anhydride was dissolved in pyridine to make a volume of 100 ml) was added and stirred for 1 hour. To this, phenolphthalein test solution was added as an indicator and held for 30 seconds. Thereafter, the solution was titrated with a 0.1N alcoholic potassium hydroxide solution until the solution turned light red.
The hydroxyl value was determined by the following formula. The hydroxyl value was a numerical value in the dry state of the resin (unit: mgKOH / g).
Hydroxyl value (mgKOH / g) = [{(ba) × F × 28.25} / S] / (Non-volatile content concentration / 100) + D
Where S: Amount of sample collected (g)
a: Consumption of 0.1N alcoholic potassium hydroxide solution (ml)
b: Consumption of 0.1N alcoholic potassium hydroxide solution in the empty experiment (ml)
F: Potency of 0.1N alcoholic potassium hydroxide solution
D: Acid value (mgKOH / g)

《Acid value (AV)》
About 1 g of a sample was accurately weighed in a stoppered Erlenmeyer flask and dissolved by adding 100 ml of a toluene / ethanol (volume ratio: toluene / ethanol = 2/1) mixed solution. To this was added a phenolphthalein test solution as an indicator, which was held for 30 seconds, and then titrated with a 0.1N alcoholic potassium hydroxide solution until the solution turned light red.
The acid value was determined by the following formula. The acid value was a numerical value of the dry state of the resin (unit: mgKOH / g).
Acid value (mgKOH / g) = {(5.611 × a × F) / S} / (Nonvolatile content concentration / 100)
Where S: Amount of sample collected (g)
a: Consumption of 0.1N alcoholic potassium hydroxide solution (ml)
F: Potency of 0.1N alcoholic potassium hydroxide solution

<< Residual amount of isocyanate group (NCO) (%) >>
About 1 g of sample is accurately weighed in a stoppered Erlenmeyer flask and mixed with 25 ml of chlorobenzene and di-n-butylamine / o-dichlorobenzene (mass ratio: di-n-butylamine / o-dichlorobenzene = 1 / 24.8). Add 10 ml of solution and dissolve. To this, 80 g of methanol and bromophenol blue reagent were added as indicators and titrated with a 0.1N alcoholic hydrochloric acid solution. Titration was continued until the solution was yellowish green and held for 30 seconds. The NCO residual amount (%) was determined by the following formula.
NCO residual amount (%) = [0.42 × (BC) × F] / S
Where S: Amount of sample collected (g)
B: Consumption of 0.1N alcoholic hydrochloric acid solution required for sample titration (ml)
C: Consumption of 0.1N alcoholic hydrochloric acid solution required for titration of blank test (ml)
F: Potency of 0.1N alcoholic hydrochloric acid solution

<< Glass transition temperature (Tg) >>
An “SSC5200 disk station” (manufactured by Seiko Instruments Inc.) was connected to a robot DSC (differential scanning calorimeter, “RDC220” manufactured by Seiko Instruments Inc.) and used for measurement.
About 10 mg of a sample is put in an aluminum pan, weighed and set in a differential scanning calorimeter, and kept for 5 minutes at a temperature of 100 ° C. using the same type of aluminum pan without a sample as a reference. It was rapidly cooled to 120 ° C. Then, it heated up with the temperature increase rate of 10 degree-C / min, and determined the glass transition temperature (Tg, unit: degreeC) from the obtained DSC chart.

  Abbreviations of materials used in Synthesis Examples 1 to 25 are shown below. In Table 1, numerical values represent parts, and blanks mean no blending.

Low-polar short-chain polyol BEPG: 2-butyl-2-ethyl-1,3-propanediol Polyol (a1-1) having a surface tension of 20 mN / cm or more and less than 40 mN / cm (also known as low-polar polyol)
EPOL: EPOL (Mn = 2,000, hydroxyl value = 53, acid value <0.5, hydrogenated linear liquid type) (made by Idemitsu Kosan Co., Ltd.), GI2000: NISSO GI-2000 (Mn = 2,100, Hydroxyl value = 47, acid value <0.5, hydrogenated linear liquid type (manufactured by Nippon Soda Co., Ltd.), PTG2000: PTG 2000 (Mn = 2,000, hydroxyl value = 56, acid value <0.05, linear wax Type) [manufactured by Hodogaya Chemical Co., Ltd.], PP2000: Newpol PP-2000 (Mn = 2,000, hydroxyl value = 56, acid value <0.5, linear liquid type, diol) [manufactured by Sanyo Chemical Industries, Ltd. FF3320: Primepole FF-3320 (Mn = 3,000, hydroxyl value = 56, acid value <0.5, linear liquid trifunctional type) [manufactured by Sanyo Chemical Industries], G3000: ADEKA POLYE Tell G-3000B (Mn = 3,000, hydroxyl value = 56, acid value <0.5, linear liquid trifunctional type) [manufactured by ADEKA Corporation], AM502: ADEKA polyether AM-502 (Mn = 4,600, Hydroxyl value = 36, acid value <0.1, linear liquid trifunctional type) [manufactured by Adeka]

Low-polar polyether polyol PP1000: Newpol PP-1000 (Mn = 1,000, hydroxyl value = 112, acid value <0.5, linear liquid type)) (manufactured by Sanyo Chemical Industries)
-Polyol (a1-2) having a surface tension of 40 mN / cm or more and less than 60 mN / cm (also known as a high polarity polyol)
PEG600: PEG600 (Mn = 600, hydroxyl value = 192, acid value <0.5, linear liquid type, diol) (manufactured by Sanyo Chemical Industries), PEG1000: PEG1000 (Mn = 1,000, hydroxyl value = 112, acid) Value <0.5, linear waxy type, diol) (manufactured by Sanyo Chemical Industries), P1010: Kuraray polyol P1010 (Mn = 1,000, hydroxyl value = 112, acid value <0.5, linear liquid type, diol) ) [Manufactured by Kuraray Co., Ltd.], F1010: Kuraray polyol F1010 (Mn = 1,000, hydroxyl value = 168, acid value <0.5, linear liquid trifunctional type) [manufactured by Kuraray Co., Ltd.], F3010: Kuraray polyol F3010 (Mn = 3,000, hydroxyl value = 56, acid value <0.5, linear liquid trifunctional type) [manufactured by Kuraray Co., Ltd.], F7-67: Adekani Ace F7-67 (Mn = 2,000, hydroxyl value = 56, acid value <0.3, linear liquid type) [manufactured by Adeka Corporation], C1015N: Kuraray polyol C-1015N (Mn = 1,000, hydroxyl value = 112, acid value <0.5, linear liquid type, diol) [manufactured by Kuraray Co., Ltd.]
・ High polar short chain polyol P6010: Kuraray polyol P6010 (Mn = 6,000, hydroxyl value = 19, acid value <0.5, linear liquid type) [manufactured by Kuraray Co., Ltd.]

・ Polyisocyanate (a2)
HDI: hexamethylene diisocyanate, IPDI: 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate, TDI: 2,4-tolylene diisocyanate / catalyst DBU: diazabicycloundecene, DOTDL: dioctyltin dilaurate / organic solvent ACAC: acetylacetone, TOL: toluene, EAC: ethyl acetate

Using the polyurethane resin obtained in the above synthesis examples, pressure sensitive adhesives were prepared by the following methods, respectively.
(Examples 1-46, Comparative Examples 1-8)
The obtained polyurethane resin, reactive compound (B), ester compound (C) and optional components were blended according to the mass ratio (parts) described in Table 2, and ethyl acetate was added as an organic solvent to give a nonvolatile content concentration of 50%. The pressure-sensitive adhesive was obtained. The obtained pressure-sensitive adhesive was applied to each substrate, dried, cured, and bonded to create an adhesive film, which was evaluated by the following method. Each result is shown in Table 3. In addition, the numerical value of the lower stage of the symbol of each material in Table 2 represents the surface tension of each material.

<< Evaluation of pot life >>
About the obtained pressure-sensitive adhesive, after blending, the viscosity at 25 ° C. was changed every 8 hours until 8 hours later using a B-type viscometer (TV-22 manufactured by Toki Sangyo Co., Ltd.), and the rotor No. Measurement was performed under conditions of 3, 25 ° C., 12 rpm, and 1 minute rotation, and pot life was evaluated in three stages. In the case of “○” or “△” evaluation, there is no problem in actual use.
○: Viscosity increase rate up to 8 hours is less than 50%. Good.
Δ: Viscosity increasing rate up to 8 hours is 50% or more and less than 100%. Can be used practically.
X: Solution layer separation or turbidity occurs in less than 8 hours, gelation occurs, or viscosity increase rate is recognized to be 100% or more. Not practical.
Here, the viscosity increase rate was calculated by the following method.
Viscosity increase rate (%) = 100 × {(viscosity after 8 hours storage) − (viscosity immediately after adjustment)} / (viscosity immediately after adjustment)

<< Evaluation of foam removal characteristics >>
The obtained polyurethane resin, reactive compound (B), ester compound (C) and optional components were blended in a size 225 mayonnaise bottle (manufactured by Nippon Shokubai Kogyo Co., Ltd.) according to the mass ratio (parts) described in Table 2. Then, ethyl acetate was added as an organic solvent to adjust the non-volatile content concentration to 50%, and an air motor agitator (“LZB14-S-1” manufactured by Chuo Rika Co., Ltd.) equipped with a disperse blade was used at 25 ° C. and 2000 rpm. The mixture was stirred for 1 minute under rotating conditions, and then allowed to stand at 25 ° C., and the time for removing bubbles was visually evaluated in three stages. In the case of “○” or “△” evaluation, there is no problem in actual use.
○: Bubbles disappear within 15 minutes. Very good.
Δ: Bubbles disappeared in 15 minutes to 1 hour. Can be used practically.
X: It takes 1 hour or more to disappear. Bad.

<Evaluation of coatability>
The obtained pressure-sensitive adhesive was dried on a 38 μm-thick polyethylene terephthalate film (Therapy MF: manufactured by Toray Film Processing Co., Ltd.) (hereinafter referred to as “release liner”) as a substrate. Was applied to a thickness of 25 μm and dried with hot air at 100 ° C. for 2 minutes to form an adhesive layer. Next, a 100 μm thick polyethylene terephthalate film (PET film) was bonded to the coated surface to produce an adhesive film composed of 100 μm thick PET film / adhesive layer / release liner. And the state of the adhesive layer surface (coating surface) after peeling a release liner was observed visually and evaluated in three steps. In the case of “○” or “△” evaluation, there is no problem in actual use.
○: A smooth coated surface was obtained. Good.
Δ: Some repelling and foaming are observed at the end of the coated surface. Can be used practically.
×: Repelling, foaming and streaking were observed on the coated surface. Bad.

<< Evaluation of optical characteristics >>
The obtained pressure-sensitive adhesive was coated on the release liner so that the thickness after drying was 50 μm, and dried with hot air at 100 ° C. for 2 minutes to form an adhesive layer. Next, a separate release liner was bonded to the adhesive layer to produce an adhesive film in which the adhesive layer was sandwiched between the release liners, and cured for 7 days in an environment of 23 ° C. and 50% relative humidity.
Next, both release liners were removed, the appearance of the adhesive layer alone was visually determined, and haze was measured with “NDH-300A (Nippon Denshoku Industries Co., Ltd.)”. In the case of “○” or “△” evaluation, there is no problem in actual use.
○: No cloudiness or the like is observed, and HAZE: less than 0.5. Good.
Δ: No cloudiness or the like is observed, but HAZE: 0.5 or more and less than 2, and can be used without any practical problem.
X: Cloudiness is observed or HAZE: 2 or more. Bad.

<< Evaluation of workability >>
Each adhesive film prepared by the same method as in the above << Evaluation of coatability >> was cured for 7 days in an environment of 23 ° C and 50% relative humidity. Then, it cut | judged to 100 mm in width x 100 mm in length, it piled up 20 sheets of this, and the state of the adhesion layer protruding from the edge part of an adhesive film at the time of pressing on the conditions of 40 degreeC-60Kg / cm < ² > for 1 hour is as follows. It was evaluated in three stages. In the case of “○” or “△” evaluation, there is no problem in actual use.
○: No protruding adhesive layer is observed. Good.
Δ: Protrusion of the adhesive layer of less than 0.3 mm is observed, but can be used practically.
X: Protrusion of the adhesive layer of 0.3 mm or more is observed. Bad.

《Evaluation of self-adhesion》
Each adhesive film prepared by the same method as in the above << Evaluation of coatability >> was cured for 7 days in an environment of 23 ° C and 50% relative humidity. Then, cut into a width of 25 mm and a length of 100 mm to prepare two sheets, peel off each release liner, and stick the exposed adhesive layers together using a laminator in an environment of 23 ° C. and 50% relative humidity. And kept for 20 minutes to obtain a measurement sample. The test sample was peeled off at 23 ° C. and 50% relative humidity using a tensile tester (“Tensilon” manufactured by Orientec Co., Ltd.) at a peeling speed of 300 mm / min and T-peeling conditions. While visually judging the external appearance of the single adhesive layer, the haze was measured with “NDH-300A (manufactured by Nippon Denshoku Industries Co., Ltd.)” to evaluate self-adhesion. In the case of “○” or “△” evaluation, there is no problem in actual use.
○: No cloudiness or surface roughness was observed, and HAZE: less than 0.5. Good.
Δ: No cloudiness or surface roughness is observed, but HAZE: 0.5 or more and less than 2, and can be used practically without any trouble.
X: Cloudiness and surface roughness are observed, or HAZE: 2 or more. Bad.

<< Evaluation of wet spreadability >>
The obtained pressure-sensitive adhesive is coated on a 50 μm-thick polyethylene terephthalate film (PET film) as a substrate so that the thickness after drying is 15 μm, and dried with hot air at 100 ° C. for 2 minutes. Then, an adhesive layer was formed. Next, a 38 μm release liner (Therapel MF: manufactured by Toray Film Processing Co., Ltd.) was bonded to the coated surface to prepare an adhesive film having a structure of 50 μm thick PET film / adhesive layer / release liner, and a 23 ° C. relative humidity of 50%. Cured for 7 days in the environment. And this adhesive film was cut | judged to width 100mm x length 100mm, and it was set as the measurement sample. Next, a float glass plate having a thickness of 2 mm, a width of 150 mm, and a length of 150 mm is brought into contact with the float glass plate in a state where only one side of the adhesive layer from which the release liner of the adhesive film has been peeled is inclined by 45 °. The time (seconds) required for the entire sample surface to come into contact with the glass plate (wet spread on the glass plate) was evaluated as the wet spread property in the following three stages. In the case of “○” or “△” evaluation, there is no problem in actual use.
○: Wetting spread time is less than 2 seconds. Good.
Δ: Wetting and spreading time is 2 seconds or more and less than 4 seconds. Can be used practically.
X: Time to spread wet is 4 seconds or more. Bad.

<Measurement of peel strength>
Each of the adhesive films prepared by the same method as the above << Evaluation of wettability >> is cut into a width of 25 mm x a length of 100 mm, the release liner is peeled off, and the exposed adhesive layer is a non-alkali glass plate having a thickness of 1.2 mm. The film was attached using a laminator in an environment of 23 ° C. and 50% relative humidity. Then, it hold | maintained for 20 minutes in the autoclave of conditions of 50 degreeC and 5 atmospheres, and obtained the measurement sample. The measurement sample was allowed to stand at 23 ° C. for 1 day, and was then peeled at a peeling speed of 300 mm / min and a peeling angle in a 23 ° C. and 50% relative humidity environment using a tensile tester (“Tensilon” manufactured by Orientec) The peel strength was measured under the condition of 180 degrees (measurement of peel strength one day after bonding). Further, after the measurement sample was allowed to stand for 14 days in an environment of 23 ° C. and 50% relative humidity, the peel strength was measured by the same method (measurement of peel strength after 14 days of bonding). This peel strength was evaluated as an adhesive strength in three stages. In the case of “○” or “△” evaluation, there is no problem in actual use.
○: Adhesive strength is less than 10.0 (mN / 25 mm). Good.
Δ: Adhesive strength is 10.0 (mN / 25 mm) or more and less than 15.0 (mN / 25 mm). Can be used practically.
X: Adhesive force is 15.0 (mN / 25 mm) or more. Poor and impractical.

<< Evaluation of removability (reworkability) >>
Each adhesive film created by the same method as in the above << Evaluation of wettability >> is cut into a size of 25 mm x 150 mm, the release liner is peeled off, and a laminator is attached to a 2 mm thick float glass plate, An optical laminate of an adhesive film and a glass plate was obtained by holding in an autoclave at 50 ° C. and 5 atm for 20 minutes.
The adhesive film of this laminated body was peeled off at a speed of 50 mm / min in the direction of 180 °, and the fogging of the glass surface after peeling was visually observed and evaluated in three stages. In the case of “○” or “△” evaluation, there is no problem in actual use.
○: No cloudiness and no problem in practical use. Very good.
Δ: Some cloudiness is observed, but there is no practical problem. Good.
X: Transfer of the pressure-sensitive adhesive is recognized over the entire surface, and is not practical.

<< Evaluation of durability (heat resistance, heat and humidity resistance) >>
As a heat resistance test, an adhesive film prepared by the same method as the above << Evaluation of wettability >> was cut into a width of 100 mm and a length of 100 mm. Next, the release liner of the adhesive film is removed, and the exposed adhesive layer is applied to one side of a 1.2 mm-thick alkali-free glass plate under a 50 ° C. atmosphere at a pressure of 5 kg / cm ² and held in an autoclave for 20 minutes. And then left in an atmosphere at 80 ° C. for 500 hours. After standing, the temperature was returned to 25 ° C., and the adhesive film was floated and peeled off, and the occurrence of foaming was visually observed and evaluated in three stages.
As a heat and humidity resistance test, a sample was prepared in the same manner as the heat resistance test, and left in a constant temperature and humidity chamber at 60 ° C. and a relative humidity of 90% for 500 hours. . After standing, the temperature was returned to 25 ° C., and the adhesive film was floated and peeled off, and the occurrence of foaming was visually observed and evaluated in three stages. In the case of “○” or “△” evaluation, there is no problem in actual use.
Foaming is a state in which relatively large bubbles are generated at the interface between the adhesive layer and the glass (other than the peripheral edge).
The floating / peeling is a state where the polarizing film adhesive film is lifted from the glass and peeled off.
Each evaluation standard is as follows.
○: No foaming, floating or peeling occurs. Good.
Δ: Minor occurrence of foaming, floating or peeling with a diameter of 0.5 mm or less is observed, but it can be used practically.
X: Remarkable generation | occurrence | production, such as foaming, a float, peeling, is recognized over the whole surface. Cannot be used practically.

The materials used in Examples and Comparative Examples are shown below. In Table 2, a blank means no blending.
Polyurethane resin Compounds obtained in each synthesis example shown in Table 1 (Synthesis Examples 1 to 25)
Reactive compound (B) having a functional group capable of reacting with a hydroxyl group
HDI / TMP: trimethylolpropane adduct of hexamethylene diisocyanate, HDI / Nu: trimer having isocyanurate ring of hexamethylene diisocyanate, IPDI / TMP: 3-isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate Trimethylolpropane adduct, XDI / TMP: trimethylolpropane adduct of xylylene diisocyanate, MAS: 3-aminopropyltrimethoxysilane, EPS: 3-glycidoxypropyltrimethoxysilane, HMMPM: hexamethylolmelamine penta Methyl ether ester compounds (C)
OLM: Methyl oleate, RS735: Polyethylene glycol diethylhexanoate [“ADEKA Sizer RS735” manufactured by ADEKA Corporation], POOC: monooctyl phosphate, POEOP: polyoxyethylene octyl ether phosphate ester, T-80: polyoxyethylene diester (Glycerin) borate monooleate (EO addition mole number: 6-20) ["Emalbon T-80" manufactured by Toho Chemical Co., Ltd.]
・ Ionic compounds (D)
OPFI: 1-octyl-4-methylpyridinium bis (fluorosulfonyl) imide / hydrolysis inhibitor (E)
CBI: Carbodiimide [Nisshinbo Co., Ltd., trade name Carbodilite V-09GB]
・ Other ingredients (P)
AO50: Phenolic antioxidant [“Adeka Stub AO-50” manufactured by Adeka Corporation]

As described above, the pressure-sensitive adhesive of the present invention has a pot life and bubble removal in Examples 1 to 3, 5 to 9, 11 to 15, 18 to 21, 24 to 33, 36 to 41, and 44 to 46. 12 items of “△” evaluation (practical level) in all of properties, coating properties, optical properties, workability, self-adhesion properties, wet spread properties, peel strength, re-peelability, heat resistance, and heat and humidity resistance It is found that the number is 3 or less, and the others are all excellent because of the “◯” evaluation (good level).
Moreover, in Examples 4, 10, 16, 17, 22, 23, 34, 35, 42 and 43, the “△” evaluation (practical level) of each evaluation is 4 to 12 out of 13 items. Since there is no “x” evaluation (defect level), it can be used practically without any problem.
On the other hand, in Comparative Examples 1-8, pot life, foam removal property, coating property, optical property, workability, self-adhesion property, wet spread property, peel strength, re-peel property, heat resistance, and heat and moisture resistance It can be seen that either is extremely inferior.

  The pressure-sensitive adhesive according to the present invention has good productivity, has excellent durability such as heat resistance and moist heat resistance, and has excellent wet spreading properties, so that it can be used in the construction field (for example, exterior, interior, etc.). , Equipment, etc.), electrical equipment field (for example, home appliances, kitchen equipment, air conditioning, etc.), transport equipment field (for example, ships, automobiles, etc.), furniture field, various industrial fields other than optical fields such as sundries field, etc. Can be used for applications other than protective films.

Claims (11)

A pressure sensitive adhesive comprising a polyurethane resin having a hydroxyl group (A), a reactive compound (B) having a functional group capable of reacting with a hydroxyl group, and an ester compound (C),
The polyurethane resin (A) includes a polyol (a1-1) having a surface tension of 20 mN / cm or more and less than 40 mN / cm and a number average molecular weight of 2,000 to 10,000, and a surface tension of 40 mN / cm or more and 60 mN / cm. A reaction product of a polyisocyanate (a2) with a polyol (a1) containing a polyol (a1-2) having a number average molecular weight of less than 400 and 4,000,
The number average molecular weight of the polyol (a1-1) is a pressure-sensitive adhesive having a number average molecular weight equal to or higher than the number average molecular weight of the polyol (a1-2).   The pressure-sensitive adhesive according to claim 1, comprising 50 to 99% by mass of polyol (a1-1) and 1 to 50% by mass of polyol (a1-2) in 100% by mass of the polyol (a1).   The pressure sensitive type of Claim 1 or 2 containing 0.1-50 mass parts of reactive compounds (B) which have a functional group which can react with a hydroxyl group with respect to 100 mass parts of polyurethane resins (A) which have the said hydroxyl group. adhesive.   The pressure sensitive adhesive according to any one of claims 1 to 3, comprising 1 to 100 parts by mass of an ester compound (C) with respect to 100 parts by mass of the polyurethane resin (A) having a hydroxyl group.   The pressure-sensitive adhesive according to any one of claims 1 to 4, wherein the polyurethane resin (A) has a weight average molecular weight of 10,000 to 500,000.   The pressure-sensitive adhesive according to any one of claims 1 to 5, wherein the polyol (a1) contains a polyol having 3 or more hydroxyl groups.   The pressure sensitive adhesive according to any one of claims 1 to 6, wherein the reactive compound (B) comprises a polyisocyanate (b1).   The pressure-sensitive adhesive according to any one of claims 1 to 7, wherein the ester compound (C) has a surface tension of 20 mN / cm or more and less than 40 mN / cm.   Furthermore, the pressure sensitive adhesive of any one of Claims 1-8 containing an ionic compound (D).   A pressure-sensitive adhesive film comprising a base material (G) and an adhesive layer that is a cured product of the pressure-sensitive adhesive according to any one of claims 1 to 9.   The optical laminated body provided with the optical film (I), the contact bonding layer which is a hardened | cured material of the pressure sensitive adhesive of any one of Claims 1-9, and glass.