TW202106744A - Hydroxyl group-terminated urethane prepolymer-containing solution and method for producing the same, pressure-sensitive adhesive, and pressure-sensitive adhesive sheet and method for producing the same - Google Patents

Abstract

Provided is a solution that contains a hydroxyl-terminated urethane prepolymer. The solution is for use in an adhesive, uses a reduced amount of an organic solvent, has a relatively high solid component concentration, and has a relatively low viscosity. Also provided is an adhesive that uses a reduced amount of an organic solvent, has a relatively high solid component concentration, and has a relatively low viscosity when applied and therefore has favorable application suitability. This solution that contains a hydroxyl-terminated urethane prepolymer is for an adhesive and includes a hydroxyl-terminated urethane prepolymer (UPH) that is the product of a reaction between: at least one type of active-hydroxyl-group-containing compound (HX) that has a plurality of active hydroxyl groups per molecule thereof; and at least one type of polyisocyanate (N). The solid component concentration of the solution is at least 80 mass%, and the viscosity of the solution at 25 DEG after standing for one hour at 25 DEG C immediately after being prepared is no greater than 8000 mPa·s. This adhesive includes: the solution that contains a hydroxyl-terminated urethane prepolymer; and a polyfunctional isocyanate compound (I).

Description

Hydroxyl terminal urethane prepolymer solution, its manufacturing method, adhesive, and adhesive sheet and its manufacturing method

The invention relates to a solution of a hydroxyl terminal urethane prepolymer for an adhesive, a method for producing the same, an adhesive, and an adhesive sheet and a method for producing the same.

Since the past, as a surface protection sheet for various members, an adhesive sheet having an adhesive layer formed on a base sheet has been widely used. As the adhesive, there are acrylic adhesives, silicone adhesives, and urethane adhesives. Acrylic adhesives have excellent adhesion, but because of their strong adhesion, they have poor releasability after being attached to the adherend. Particularly after time in a high-temperature and high-humidity environment, the re-peelability is further reduced due to the increase in the adhesive force, and there is a tendency that the adhesive remains on the surface of the adherend after re-peeling is contaminated by the adherend. Regarding silicone adhesives, there is also a concern that the adherend is easily contaminated, and the relatively low molecular weight silicone resin is volatilized and adsorbed on the surface of electronic components and other devices, causing problems. In contrast, the urethane-based adhesive has good adhesion to the adherend, and at the same time, is relatively excellent in repeelability, and is not easily volatilized. In this specification, "adhesive" is an adhesive with re-peelability (re-peelable adhesive), and "adhesive sheet" is an adhesive sheet with re-peelability (re-peelable adhesive sheet).

Flat panel displays such as liquid crystal display (LCD) and organic electroluminescence display (OELD), as well as touch panel displays combining the flat panel display and touch panel, are widely used in televisions (television , TV), personal computers (PC), mobile phones, and portable information terminals and other electronic equipment. Urethane-based adhesive sheets can be preferably used as flat panel displays and touch panel displays, as well as the substrates (glass substrates, and indium tin oxide formed on the glass substrates) manufactured or used in these manufacturing steps ( Indium tin oxide (ITO) film, ITO/glass substrate, etc.) and surface protection sheet for optical components, etc.

As a manufacturing method of a urethane adhesive, there is the following method: using a hydroxyl-terminated urethane prepolymer and a polyfunctional isocyanate compound as a reaction product of an active hydrogen group-containing compound such as a polyol and a polyisocyanate The method; and the one-shot method of reacting the polyol and the polyfunctional isocyanate compound without using the hydroxyl-terminated urethane prepolymer (one shot method).

A general adhesive sheet manufacturing method includes: a coating step, applying an adhesive on a substrate sheet; a heating step, heating and drying the formed coating layer to form an adhesive layer containing a hardened object of the adhesive; In the winding step, the obtained adhesive sheet is wound on the core to form the form of the adhesive sheet roll; and the curing step is to cure the adhesive sheet roll. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 5194801 [Patent Document 2] Japanese Patent No. 6270818 [Patent Document 3] Japanese Patent No. 5466366 [Patent Document 4] Japanese Patent No. 6070633

[The problem to be solved by the invention]

Urethane-based adhesives harden soon after manufacture, but if the initial curability is too high, there is a concern that the pot life will be shortened until the adhesive is applied to the substrate sheet. In the meantime, the viscosity of the adhesive becomes too high to be uniformly applied. If the initial curability of the urethane-based adhesive is too low, there is a concern that the coating layer or the adhesive layer is heated and dried by the hot air during the heating and drying of the coating layer, or the adhesive sheet obtained after the heating and drying is wound The adhesive layer is affected by the mechanical stress during time and curing, resulting in poor surface appearance such as core step marks, orange peel defects, and curling in the adhesive layer. The urethane-based adhesive preferably has a good pot life and good initial curing properties.

Previously, generally, the urethane-based adhesive contained an organic solvent, thereby adjusting it to a relatively low viscosity suitable for coating. However, in terms of environmental aspects, the use of volatile organic compounds (VOC) is not good, and the amount of use thereof is preferably small. Regarding the conventional urethane-based adhesives, if the amount of organic solvent used is reduced, the viscosity of the adhesive will increase, and the coating properties tend to decrease. It is preferable to provide a urethane-based adhesive with a relatively low viscosity suitable for coating even if the amount of the organic solvent used is reduced to increase the solid content concentration. Conventionally, the solid content concentration of the urethane-based adhesive is generally less than 70% by mass, but from the viewpoint of reducing VOC, it is preferably 70% by mass or more, and more preferably 80% by mass or more.

As related documents of the present invention, Patent Document 1 to Patent Document 4 can be cited. Patent Document 1 discloses a method for producing a urethane resin for adhesives, which involves reacting a polyol and a polyisocyanate compound at a ratio of excess isocyanate groups to obtain an isocyanate group-terminated prepolymer, and then extending the chain The isocyanate group-terminated prepolymer reacts with the isocyanate group-terminated prepolymer, and if necessary, the end-stopper is reacted. In the method for producing the urethane resin, The chain extender contains a polyfunctional compound (X) having three or more functional groups capable of reacting with isocyanate groups, two of the functional groups of the polyfunctional compound (X) are primary hydroxyl groups, and the remaining functional groups are secondary hydroxyl groups Or tertiary hydroxyl, The polyfunctional compound (X) is at least one selected from the group consisting of the compound represented by the chemical formula (1) and the compound represented by the chemical formula (2) (first invention). Patent Document 1 discloses an adhesive containing a urethane resin obtained by the production method (fifth invention).

Patent Document 1 discloses a method for producing a solution of a hydroxyl-containing terminal urethane prepolymer by two-stage polymerization and the urethane of a solution containing the hydroxyl-containing terminal urethane prepolymer Department of adhesive. Patent Document 1 states that "in the adhesive of the present invention, the urethane resin is not gelled, so in order to reduce the viscosity, the solid content concentration may not be lowered." (paragraph 0055). However, the solid content concentration of the polyurethane solutions obtained in Examples 1 to 8 was as low as 47% by mass to 50% by mass (Table 1), and the viscosity at 24°C was as low as 3700 mPa·s to 5100 mPa·s (Table 1), it is estimated that the solid content concentration of the adhesive using this polyurethane solution is low, and it cannot be said that the VOC reduction effect is sufficient. That is, Patent Document 1 does not specifically describe a solution of a hydroxyl-containing terminal urethane prepolymer having a high solid content concentration and an adhesive having a high solid content concentration containing the solution.

Patent Document 2 discloses a solvent-free polyurethane adhesive, which is ^{an active hydrogen compound having an average molecular weight of 1.2×10 4} or more and an average functional group number of 3, and (B) an average molecular weight of 0.1× It is obtained ^{by reacting an active hydrogen compound having 10 4} or more and an average number of functional groups of 2 and (C) an organic polyisocyanate having an average number of functional groups of 2 (first invention). Patent Document 2 states that "The polyurethane adhesive of the present invention obtained by combining an active hydrogen compound (A) and an active hydrogen compound (B) is a polymer having a moderate cohesive force and a soft structure. It is better in terms of the aspect. The polyurethane-based adhesive obtained in the manner described above achieves a moderate viscosity when the mixture is applied, which is also advantageous in terms of coatability.” (paragraph 0019). However, the urethane-based adhesive described in Patent Document 2 is a urethane-based adhesive obtained by a single method. Generally, the adhesive layer using the urethane-based adhesive obtained by the single-pass method is hard, and the surface smoothness of the adhesive layer tends to be easily deteriorated due to hardening shrinkage. In particular, since the urethane-based adhesive described in Patent Document 2 does not contain diluents such as solvents and plasticizers, it cannot be said that the coating properties are good, and the tendency is remarkable. The viscosity of the urethane-based adhesive described in Patent Document 2 is unknown.

Patent Document 3 discloses a one-component solventless urethane adhesive composition comprising: (A) a terminal isocyanate group-containing amine group obtained by reacting a polyol with an excess amount of a polyisocyanate compound Formate prepolymer, (B) fine powder coating amine, and (C) adhesion imparting agent (first invention). It is described in Patent Document 3 that "it is a solvent-free adhesive composition that does not substantially contain a solvent. Therefore, when an adhesive is produced from the adhesive composition of the present invention, it is possible to prevent odors or volatile organic compounds. Environmental pollution caused by chemical compounds (VOC), etc." (paragraph 0025). However, since the urethane-based adhesive described in Patent Document 3 does not contain diluents such as solvents and plasticizers, the coating properties are poor. The viscosity of the urethane-based adhesive described in Patent Document 3 is unknown.

Patent Document 4 discloses a peelable urethane adhesive composition, which contains a polyurethane resin having a primary hydroxyl group at the end and a hydroxyl value of 10 mgKOH/g-40 mgKOH/g (A ) 100 parts by weight, 1 part by weight of polyfunctional isocyanate compound (B) to 20 parts by weight, and at least one selected from polyalkylene glycol-based compounds, epoxy-based compounds, and phosphate ester-based compounds (C) 25 parts by weight- 100 parts by weight (first invention). In Synthesis Example 1 to Synthesis Example 5 and Example 1 to Example 18 of Patent Document 4, a polyurethane resin solution containing 60% by mass of non-volatile content and a urethane resin solution containing the same were produced Adhesive. The solid content concentration of the polyurethane resin solution obtained in Synthesis Example 1 to Synthesis Example 5 is at the previous general level, including the urethane-based adhesive described in Example 1 to Example 18 The solid content concentration of is estimated to be the previous general level, the VOC reduction effect is not sufficient, and the viscosity is unknown.

The present invention was made in view of the above circumstances, and its object is to provide a hydroxyl-containing terminal urethane prepolymer for adhesives with a reduced amount of organic solvents, a relatively high solid content concentration, and a relatively low viscosity.物的Solution. In addition, the object of the present invention is to provide an adhesive with a reduced usage amount of organic solvents, a relatively high solid content concentration, and a relatively low viscosity at the time of application to have good application adaptability. [Means to solve the problem]

The solution of the hydroxyl terminal urethane prepolymer for the adhesive of the present invention contains: Hydroxyl terminal urethane prepolymer (UPH), the hydroxyl terminal urethane prepolymer (UPH) is one or more active hydrogen group-containing compounds having multiple active hydrogen groups in one molecule ( HX), reaction products with more than one polyisocyanate (N), and The solid content concentration is 80% by mass or more, and the viscosity at 25°C after being allowed to stand at 25°C for 1 hour shortly after preparation is 8000 mPa·s or less.

In the solution of the hydroxyl terminal urethane prepolymer for the adhesive of the present invention, More than one active hydrogen group-containing compound (HX) preferably contains more than one polyol (HA) with a number average molecular weight of 1000 or more, and a molecule with a number average molecular weight of less than 1000 having multiple active hydrogen groups. More than one compound containing active hydrogen groups (HB).

The adhesive of the present invention includes the solution of the hydroxyl-containing terminal urethane prepolymer of the present invention and the polyfunctional isocyanate compound (I). The adhesive of the present invention preferably has a solid content concentration of 80% by mass or more, and the viscosity at 25°C after being left to stand at 25°C for 3 hours shortly after preparation is 5000 mPa·s or less. The adhesive sheet of the present invention includes a base sheet and an adhesive layer containing a cured product of the adhesive of the present invention. [Effects of the invention]

According to the present invention, it is possible to provide a solution of a hydroxyl terminal urethane prepolymer for an adhesive with a reduced usage of organic solvents, a relatively high solid content concentration, and a relatively low viscosity. In addition, according to the present invention, it is possible to provide an adhesive with a reduced usage of organic solvents, a relatively high solid content concentration, and a relatively low viscosity at the time of application to have good application adaptability.

The solution of the hydroxyl terminal urethane prepolymer for the adhesive of the present invention contains: Hydroxyl terminal urethane prepolymer (UPH), the hydroxyl terminal urethane prepolymer (UPH) is one or more active hydrogen group-containing compounds having multiple active hydrogen groups in one molecule ( HX), the reaction product with more than one polyisocyanate (N). The adhesive of the present invention is a urethane-based adhesive containing the solution of the hydroxyl-containing terminal urethane prepolymer of the present invention and the polyfunctional isocyanate compound (I). The pressure-sensitive adhesive sheet of the present invention is a urethane-based pressure-sensitive adhesive sheet including a base sheet and an adhesive layer containing a cured product of the adhesive of the present invention.

The amount of the organic solvent used in the solution of the hydroxyl terminal urethane prepolymer used in the adhesive of the present invention is reduced, the solid content concentration is relatively high, and the viscosity is relatively low. By using the hydroxyl-containing terminal urethane prepolymer solution, the urethane-based adhesive of the present invention can be provided, that is, the amount of organic solvent used is reduced, the solid content concentration is relatively high, and the The coating time point has a relatively low viscosity to have good coating adaptability. The amount of volatile organic compound (VOC) used in the adhesive of the present invention is small, and it is preferable in terms of environmental aspects and the like.

The solution of the hydroxyl-terminated urethane prepolymer for the adhesive of the present invention has a solid content concentration of 80% by mass or more, and the viscosity at 25°C after being allowed to stand at 25°C for 1 hour shortly after preparation is Below 8000 mPa·s. The solid content concentration in the adhesive of the present invention is preferably 70% by mass or more, more preferably 80% by mass or more, and particularly preferably 90% by mass or more. The adhesive of the present invention has a viscosity at 25°C after being left at 25°C for 3 hours shortly after preparation, preferably 8000 mPa·s or less, more preferably 7000 mPa·s or less, particularly preferably 5000 mPa·s or less . The preferred viscosity range varies depending on the coating method, but when the viscosity is low, the coating property tends to be excellent. The adhesive of the present invention changes in viscosity with the passage of time shortly after preparation, and the "viscosity at 25°C after being allowed to stand at 25°C for 3 hours shortly after preparation" is assumed to be the "viscosity at the time of application". In this specification, unless otherwise noted, the "solid content concentration" and "viscosity" shall be those obtained by the method described in the section [Examples].

[Adhesive] (Solution of urethane prepolymer containing hydroxyl terminal) The solution of the hydroxyl terminal urethane prepolymer of the present invention is a solution containing a hydroxyl terminal urethane prepolymer (UPH), and the hydroxyl terminal urethane prepolymer (UPH) is It is obtained by copolymerizing one or more active hydrogen group-containing compounds (HX) having a plurality of active hydrogen groups in one molecule and one or more polyisocyanates (N). The copolymerization reaction can be carried out in the presence of more than one catalyst as necessary. More than one solvent can be used in the copolymerization reaction as necessary.

In order to achieve high solid content concentration and low viscosity of the adhesive, the hydroxyl-terminated urethane prepolymer (UPH) is preferably lower in molecular weight than the conventional hydroxyl-terminated urethane prepolymer. The weight average molecular weight (Mw) of the hydroxyl-terminated urethane prepolymer (UPH) is preferably 10,000 to 100,000, more preferably 13,000 to 80,000. Mw is preferably 60,000 or less, more preferably 15,000 to 60,000, particularly preferably 10,000 to 60,000. In this specification, "Mw" is the weight average molecular weight in terms of polystyrene calculated by gel permeation chromatography (GPC) measurement. "Mn" is the number average molecular weight in terms of polystyrene obtained by GPC measurement. These can be measured by the method described in the section of [Examples].

From the viewpoint of reducing the VOC of the adhesive, the solid content concentration in the solution of the hydroxyl-containing terminal urethane prepolymer of the present invention is 80% by mass or more, preferably 85% by mass or more, and more preferably 90% by mass % Or more, particularly preferably 95% by mass or more. From the viewpoint of the pot life and spreadability of the adhesive, the solution of the hydroxyl-terminated urethane prepolymer of the present invention has a viscosity at 25°C after being allowed to stand at 25°C for 1 hour shortly after preparation It is 8000 mPa·s or less, preferably 7000 mPa·s or less, more preferably 6000 mPa·s or less, and particularly preferably 5000 mPa·s or less. In order to achieve a high solid content concentration and low viscosity of the adhesive, and at the same time to improve the initial hardenability of the adhesive, as the raw material of the hydroxyl-terminated urethane prepolymer (UPH), more than one active hydrogen group-containing compound ( HX) preferably contains one or more polyols (HA) (higher molecular weight components) with a number average molecular weight of 1000 or more, and one or more types of polyols (HA) having multiple active hydrogen groups in a molecule with a number average molecular weight of less than 1000. Active hydrogen-based compounds (HB) (lower molecular weight components). That is, as the hydroxyl-terminated urethane prepolymer (UPH), a hydroxyl-terminated amino group as a reaction product of a plurality of active hydrogen group-containing compounds (HX) and one or more polyisocyanates (N) is preferred. Acid ester prepolymer (UPH-S), the multiple active hydrogen group-containing compounds (HX) include one or more polyols (HA) with a Mn of 1000 or more, and one or more active hydrogen-containing compounds with an Mn of less than 1000 -Based compound (HB). From the viewpoints of pot life and initial curing properties, it is preferable that one or more active hydrogen group-containing compounds (HX) as the raw material of the hydroxyl-terminated urethane prepolymer (UPH) contain The primary hydroxyl group is an active hydrogen group-containing compound. In particular, at least one active hydrogen group-containing compound (HB) preferably contains a primary hydroxyl group with moderate reactivity as the active hydrogen group.

By adjusting the mass ratio of more than one polyol (HA) as a higher molecular weight component to more than one polyisocyanate (N), the weight average molecular weight of the hydroxyl-terminated urethane prepolymer (UPH) can be made ( Mw) is relatively small, achieving high solid content concentration and low viscosity of the adhesive. Generally speaking, since the lower molecular weight hydroxy-terminal urethane prepolymer (UPH) has a tendency of poor initial hardening, the use of a lower molecular weight active hydrogen-containing compound (HB) as the hydroxy terminal One of the raw materials of urethane prepolymer (UPH), which can improve the initial hardenability. In addition to the aforementioned effects, by using a higher molecular weight polyol (HA) as one of the raw materials of the hydroxyl terminal urethane prepolymer (UPH), the wettability improvement effect of the adhesive layer can be obtained. The lower viscosity of the adhesive and the improvement of the wettability of the adhesive layer can also be achieved by adding a plasticizer (P) to the adhesive. In the case of using a plasticizer (P), a solution of a hydroxyl-containing terminal urethane prepolymer containing the plasticizer (P) can be prepared and used to make an adhesive, or it can be prepared without plastic The solution of the urethane prepolymer containing the hydroxyl terminal of the solvating agent (P) and the plasticizer (P) are used to make the adhesive. In terms of easily achieving the balance of high solid content and low viscosity of the solution of the hydroxyl-containing terminal urethane prepolymer, it is preferable to prepare the hydroxyl-containing terminal urethane prepolymer containing the plasticizer (P). And use it to make adhesives. In addition, by using a lower molecular weight active hydrogen group-containing compound (HB) as one of the raw materials of the hydroxyl terminal urethane prepolymer (UPH), the effect of improving the repeelability of the adhesive layer can be obtained.

＜Polyol (HA)＞ The number average molecular weight (Mn) of the polyol (HA) as a higher molecular weight component is 1,000 or more, preferably 1,000 to 7,000, more preferably 2,000 to 6,000, and particularly preferably 3,000 to 5,000. When Mn is 1000 or more, the cohesive force of the hydroxyl-terminated urethane prepolymer (UPH) becomes better, and the initial hardenability of the adhesive and the wettability of the adhesive layer become better. When Mn is 7000 or less, the molecular weight of the hydroxyl terminal urethane prepolymer (UPH) becomes better, and the pot life of the adhesive becomes better.

The type of polyol (HA) is not particularly limited, and examples include polyester polyols, polyether polyols, polyacrylic polyols, polycaprolactone polyols, polycarbonate polyols, castor oil-based polyols, etc. . Among them, polyester polyols, polyether polyols, and combinations of these are preferred. From the viewpoint of the wettability of the adhesive layer, more than one type of polyol (HA) is more preferably a polyether polyol having a moderate cohesive force.

As a polyester polyol, a well-known thing can be used, and the compound (esterified product) obtained by the esterification reaction of one or more polyol components and one or more acid components is mentioned.

As the polyol component of the raw material, ethylene glycol (EG), propylene glycol (PG), diethylene glycol, 1,3-butanediol, 1,4-butanediol, new Pentylene glycol, 3-methyl-1,5-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, 2,4-diethyl-1,5-pentanediol, 1 ,2-Hexanediol, 1,6-hexanediol, 2-ethyl-1,3-hexanediol, 1,8-octanediol, 1,9-nonanediol, 2-methyl-1 , 8-octanediol, 1,8-decanediol, octadecanediol, glycerin, trimethylolpropane, pentaerythritol, and hexanetriol, etc.

Examples of the acid component of the raw material include: succinic acid, methylsuccinic acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, 1,12-dodecanedioic acid, 1,14-decanedioic acid, Tetraalkanedioic acid, dimer acid, 2-methyl-1,4-cyclohexanedicarboxylic acid, 2-ethyl-1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid Formic acid, phthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalene dicarboxylic acid, 4,4'-biphenyl dicarboxylic acid, and these acid anhydrides, etc.

As the polyether polyol, known ones can be used. Examples include the use of an active hydrogen-containing compound having two or more active hydrogens in one molecule as an initiator and addition polymerization of one or more oxirane compounds. The obtained compound (addition polymer).

As the initiator, hydroxyl-containing compounds, amines, and the like can be cited. Specifically, examples include ethylene glycol (EG), propylene glycol (PG), 1,4-butanediol, neopentyl glycol, butyl ethyl pentane glycol, N-aminoethyl ethanolamine, isophor Difunctional starters such as ketone diamine and xylylenediamine; trifunctional starters such as glycerin, trimethylolpropane, and triethanolamine; pentaerythritol, ethylenediamine, and aromatic diamines, etc. Functional starter; pentafunctional starter such as diethylenetriamine, etc.

Examples of the oxirane compound include alkylene oxides such as ethylene oxide (EO), propylene oxide (PO), and butylene oxide (BO). AO); tetrahydrofuran (tetrahydrofuran, THF) and so on.

The polyether polyol is preferably an alkylene oxide adduct of an active hydrogen-containing compound (also referred to as "polyoxyalkylene polyol"). Among them, preferred are difunctional polyether polyols such as polyethylene glycol (PEG), polypropylene glycol (PPG), and polytetramethylene glycol; alkylene oxide adducts of glycerin, etc. Trifunctional polyether polyol, etc.

＜Compounds containing active hydrogen groups (HB)＞ The number average molecular weight (Mn) of the active hydrogen group-containing compound (HB) as a lower molecular weight component is less than 1,000, preferably 50 to 900, more preferably 50 to 300, and particularly more preferably 50 to 200. As mentioned above, generally, lower molecular weight hydroxyl-terminated urethane prepolymers (UPH) tend to have poor initial curing properties. Therefore, by using active hydrogen group-containing compounds as lower molecular weight components (HB) is used as one of the raw materials of the hydroxyl-terminated urethane prepolymer (UPH) to improve the initial hardenability.

Examples of the active hydrogen group include a hydroxyl group, a mercapto group, and an amino group (in this specification, unless otherwise specified, the amino group includes an imino group). Examples of the active hydrogen group-containing compound (HB) include: polyols having multiple hydroxyl groups in one molecule, polyamines having multiple amino groups in one molecule, amino alcohols having amino groups and hydroxyl groups in one molecule, Polythiols having multiple mercapto groups in one molecule, etc. One or two or more of these can be used. The active hydrogen group-containing compound (HB) may be a non-polymer or a polymer. Among them, polyhydric alcohols are preferred. Polyamines and polythiols have high reactivity and a short pot life, so when these are used, they are preferably used in combination with polyols. In addition, when the polyol contains a secondary hydroxyl group, the initial hardenability of the urethane-based adhesive does not improve. Therefore, from the standpoint of pot life and initial hardenability, active hydrogen group-containing compounds (HB) It is preferable to contain a primary hydroxyl group with moderate reactivity as the active hydrogen group, and it is more preferable to contain only the primary hydroxyl group as the active hydrogen group.

Examples of non-polymeric polyols include ethylene glycol (EG), propylene glycol (PG), diethylene glycol, triethylene glycol, 1,3-butanediol, 1,4-butanediol, new Pentylene glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, 2,4-diethyl-1 ,5-Pentanediol, 1,2-hexanediol, 1,6-hexanediol, 2-ethyl-1,3-hexanediol (also known as "1,3-octanediol"), 1,8-octanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 1,8-decanediol, octadecanediol, glycerin, trimethylolpropane (Trimethylolpropane, TMP), pentaerythritol, and hexanetriol.

Examples of polyols that can be used as polymers of the active hydrogen group-containing compound (HB) include polyester polyols, polyether polyols, polyacrylic polyols, polycaprolactone polyols, and polycarbonate polyols. , And castor oil series polyols, etc. Among them, polyester polyols, polyether polyols, and combinations of these are preferred.

Examples of polyester polyol and polyether polyol are the same as those listed in polyol (HA).

Examples of polyamines that can be used as active hydrogen group-containing compounds (HB) include ethylenediamine, 1,2-propanediamine, 1,3-propanediamine, 1,4-butanediamine, 1, 5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,12- Dodecane diamine, 1,14-tetradecane diamine, 1,16-hexadecane diamine, hexamethylene diamine, trimethyl hexamethylene diamine, imino bispropyl amine , Methyliminobispropylamine, 1,5-diamino-2-methylpentane, isophoronediamine, 1,3-diaminomethylcyclohexane, 1-cyclohexyl Amino-3-aminopropane, 3-aminomethyl-3,3,5-trimethyl-cyclohexylamine, norbornane skeleton dimethylamine, meta-xylylenediamine (meta-xylylene diamine, MXDA), hexamethylenediamine carbamate, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine and other aliphatic polyamines; 3,3'-dichloro- 4,4'-dichloro-4,4'-diaminodiphenylmethane (MOCA), 4,4'-diaminodiphenylmethane, 2,4'-diamine Diphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-diaminodiphenyl, 3,3'-diamine Biphenyl, 2,4-diaminophenol, 2,5-diaminophenol, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,3-toluenediamine, 2,4-toluene Aromatic polyamines such as diamine, 2,5-toluenediamine, 2,6-toluenediamine, 3,4-toluenediamine, and diethyltoluenediamine, etc.

Examples of amino alcohols that can be used as active hydrogen group-containing compounds (HB) include monoethanolamine, diethanolamine, 2-amino-2-methyl-1-propanol, and tris(hydroxymethyl)amino group. Monoamines having hydroxyl groups such as methane and 2-amino-2-ethyl-1,3-propanediol; diamines having hydroxyl groups such as N-(2-hydroxypropyl)ethanolamine and the like.

Examples of polythiols that can be used as active hydrogen group-containing compounds (HB) include methane dithiol, 1,3-butane dithiol, 1,4-butane dithiol, 2,3- Butane dithiol, 1,2-benzenedithiol, 1,3-benzenedithiol, 1,4-benzenedithiol, 1,10-decanedithiol, 1,2-ethanedithiol Mercaptan, 1,6-hexane dithiol, 1,9-nonane dithiol, 1,8-octane dithiol, 1,5-pentane dithiol, 1,2-propane dithiol Alcohol, 1,3-propane dithiol, toluene-3,4-dithiol, 3,6-dichloro-1,2-benzenedithiol, 1,5-naphthalene dithiol, 1,2- Diphenylthiol, 1,3-Benzodimethanethiol, 1,4-Benzodimethanethiol, 4,4'-thiodiphenylthiol, 2,5-Dimercapto-1,3,4 -Thiadiazole, 1,8-dimercapto-3,6-dioxa-octane, 1,5-dimercapto-3-thiapentane, 2-di-n-butylamino-4,6-di Mercapto-s-triazine, and mercaptan-based terminal polymers (polysulfide polymers, etc.), etc.

The number of functional groups (the number of hydroxyl groups) of one or more polyols (HA) is arbitrary, and multiple polyols (HA) having different numbers of functional groups may be used in combination as necessary. Similarly, the number of functional groups (the number of active hydrogen groups) of one or more active hydrogen group-containing compounds (HB) is arbitrary, and a plurality of active hydrogen group-containing compounds (HB) having different numbers of functional groups may be used in combination as necessary. One or more polyols (HA) may include a difunctional polyol and/or a trifunctional or more polyol. Similarly, one or more active hydrogen group-containing compounds (HB) may include a difunctional active hydrogen group-containing compound and/or a trifunctional or more active hydrogen group-containing compound. Generally speaking, the bifunctional active hydrogen group-containing compound has two-dimensional crosslinking properties and can impart moderate flexibility to the adhesive layer. The trifunctional or more active hydrogen group-containing compound has three-dimensional crosslinking properties and can impart moderate hardness to the adhesive layer. By selecting the number of functional groups (the number of active hydrogen groups) of more than one polyol (HA) and more than one active hydrogen group-containing compound (HB), the adhesive force of the urethane-based adhesive can be adjusted, Cohesive force, and peelability and other characteristics. The number of functional groups of various materials can be selected according to the application, etc., so that the properties such as adhesive force, cohesive force, and re-peelability are in a preferable range. In terms of facilitating compatibility between adhesive force and re-peelability, the one or more polyols (HA) preferably contain trifunctional or higher polyols, and more preferably contain trifunctional or higher polyether polyols. In terms of facilitating compatibility between reaction stability and cohesive force, the one or more active hydrogen group-containing compounds (HB) preferably contain a difunctional active hydrogen group-containing compound.

Multiple active hydrogen group-containing compounds (HX) as raw materials for hydroxyl-terminated urethane prepolymers (UPH) may also include more than one of the polyols (HA) and active hydrogen group-containing compounds (HB) Other known active hydrogen group-containing compounds.

＜Polyisocyanate (N)＞ As the polyisocyanate (N), known ones can be used, and examples thereof include aromatic polyisocyanates, aliphatic polyisocyanates, and alicyclic polyisocyanates.

Examples of aromatic polyisocyanates include 1,3-phenylene diisocyanate, 4,4'-diphenyl diisocyanate, 1,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate Isocyanate, 2,4-toluene diisocyanate, 2,6-toluidine diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, United Nations University Anisidine diisocyanate, 4,4'-diphenyl ether diisocyanate, and 4,4',4''-triphenylmethane triisocyanate, ω,ω'-diisocyanate-1,3-dimethylbenzene , Ω,ω'-diisocyanate-1,4-dimethylbenzene, ω,ω'-diisocyanate-1,4-diethylbenzene, 1,4-tetramethylxylylene diisocyanate, and 1,3-Tetramethylxylylene diisocyanate, etc.

Examples of aliphatic polyisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), pentamethylene diisocyanate, 1,2-propylene diisocyanate Isocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, etc.

Examples of alicyclic polyisocyanates include isophorone diisocyanate (IPDI), 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, and 1,4-cyclohexane Diisocyanate, methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4'-methylene bis (cyclohexyl isocyanate), and 1,4-bis (Isocyanate methyl) cyclohexane and the like.

In addition, examples of the polyisocyanate include trimethylolpropane adduct, biuret, allophanate, and trimer of the polyisocyanate (the trimer includes Isocyanurate ring) and so on.

As polyisocyanate (N), 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), etc. are preferable. Details will be described later, and more than one polyisocyanate (N) preferably includes isophorone diisocyanate (IPDI).

The preferred raw material formulation of the hydroxyl-terminated urethane prepolymer (UPH) is as follows. Preferably, it is the ratio of the number of moles of isocyanate groups (NCO) possessed by the polyisocyanate (N) to the total number of moles of active hydrogen groups (H) possessed by the plurality of active hydrogen group-containing compounds (HX) ( The raw material blending ratio is determined so that NCO/H) becomes 0.20 to 0.84, more preferably 0.40 to 0.80. There is a tendency that the closer the NCO/H is to 1, the easier it is to gel when synthesizing the hydroxyl-terminated urethane prepolymer (UPH). If the NCO/H is 0.84 or less, the gelation during the synthesis of the hydroxyl terminal urethane prepolymer (UPH) can be effectively suppressed.

From the viewpoint of achieving high solid content concentration and low viscosity of the adhesive, and at the same time making the initial hardenability of the adhesive good, more than one active hydrogen group-containing compound (HB) is relative to more than one polyol (HA) 100 The amount of parts by mass is preferably 0.5 parts by mass to 40 parts by mass, more preferably 2 parts by mass to 40 parts by mass, and particularly preferably 1 part by mass to 25 parts by mass. From the viewpoint of achieving high solid content concentration and low viscosity of the adhesive, and at the same time making the initial hardenability of the adhesive good, the amount of more than one polyisocyanate (N) relative to 100 parts by mass of more than one polyol (HA) It is preferably from 1 part by mass to 50 parts by mass, more preferably from 3 parts by mass to 30 parts by mass.

＜Catalyst＞ More than one catalyst can be used in the polymerization of the hydroxyl-terminated urethane prepolymer (UPH) as necessary. As a catalyst, a well-known thing can be used, and a tertiary amine type compound, an organometal type compound, etc. are mentioned. Examples of tertiary amine compounds include triethylamine, triethylenediamine, and 1,8-diazabicyclo(5,4,0)-undecene-7 (1,8-diazabicyclo( 5,4,0)-undecene-7, DBU) etc. Examples of the organometallic compound include tin-based compounds and non-tin-based compounds. Examples of tin-based compounds include dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimaleate, and dibutyltin dilaurate. DBTDL), dibutyltin diacetate, dibutyltin sulfide, tributyltin sulfide, tributyltin oxide, tributyltin acetate, triethyltin ethoxide, tributyltin ethoxide, Dioctyl tin dilaurate, dioctyl tin oxide, tributyl tin chloride, tributyl tin trichloroacetate, and tin 2-ethylhexanoate, etc. Examples of non-tin compounds include: dibutyl titanium dichloride, tetrabutyl titanate, and butoxy titanium trichloride and other titanium compounds; lead oleate, lead 2-ethylhexanoate, and lead benzoate , And lead series such as lead naphthenate; iron series such as iron 2-ethylhexanoate and iron acetone; cobalt series such as cobalt benzoate and cobalt 2-ethylhexanoate; zinc naphthenate and 2-ethyl Zinc series such as zinc caproate; zirconium series such as zirconium naphthenate. The type and amount of the catalyst can be appropriately designed within the range where the reaction proceeds well.

In the case of using multiple active hydrogen group-containing compounds (HX) at the same time, due to the difference in the reactivity of each active hydrogen group-containing compound (HX), it is easy to produce gelation or reaction solution in a single catalyst system. White turbid worries. In this case, by using two kinds of catalysts, it is easy to control the reaction (for example, the reaction rate, etc.), so that the problem can be solved. The combination of the two catalysts is not particularly limited, and examples include tertiary amine/organometallic, tin/non-tin, and tin/tin. Preferably, it is a tin system/tin system, and more preferably is dibutyltin dilaurate and tin 2-ethylhexanoate. The mass ratio of tin 2-ethylhexanoate to dibutyltin dilaurate (tin 2-ethylhexanoate/dibutyltin dilaurate) is not particularly limited, and is preferably more than 0 and less than 1, more preferably 0.2 ~0.6. If the mass ratio is less than 1, the catalyst activity is well balanced, gelation and cloudiness of the reaction solution are effectively suppressed, and the polymerization stability is further improved.

＜Solvent＞ More than one solvent may be used in the polymerization of the hydroxyl-terminated urethane prepolymer (UPH) as necessary. As the solvent, known ones can be used, and organic solvents such as methyl ethyl ketone, ethyl acetate, toluene, xylene, and acetone can generally be used. The solution of the hydroxyl terminal urethane prepolymer of the present invention can have a low viscosity even at a high solid content concentration, so the amount of organic solvent used can be reduced. The content of the organic solvent in the solution of the hydroxyl terminal urethane prepolymer of the present invention is preferably 20% by mass or less, more preferably 10% by mass or less, and may be 0% by mass. The amount of volatile organic compound (VOC) used in the solution of the hydroxyl-terminated terminal urethane prepolymer of the present invention is small, and it is preferable in terms of the environment and the like.

<Method for producing solution of hydroxyl terminal urethane prepolymer> The solution of the hydroxyl terminal urethane prepolymer may be in the presence of more than one solvent, and more than one catalyst may be used as needed to make more than one active hydrogen group-containing compound (HX) and more than one Polyisocyanate (N) is produced by copolymerization. The polymerization method is not particularly limited, and a known polymerization method such as a bulk polymerization method and a solution polymerization method can be applied. The polymerization reaction can be carried out in one stage or in multiple stages. The reaction temperature when using the catalyst is preferably less than 100°C, more preferably 50°C to 95°C, particularly preferably 60°C to 85°C. If the reaction temperature is 100° C. or higher, there are concerns that it is difficult to control the reaction rate, polymerization stability, etc., and it is difficult to produce a hydroxyl-terminated urethane prepolymer (UPH) having a desired molecular weight. The reaction temperature when no catalyst is used is preferably 100°C or higher, more preferably 110°C or higher.

Hereinafter, the preferred production method of hydroxyl-terminated urethane prepolymer (UPH-S), which is the reaction product of multiple active hydrogen group-containing compounds (HX) and one or more polyisocyanates (N), will be explained , The multiple active hydrogen group-containing compounds (HX) include one or more polyols (HA) with Mn of 1000 or more, preferably 1000-7000, and one or more of Mn less than 1000, preferably 50-900 The compound containing active hydrogen group (HB).

As the polymerization sequence of the hydroxyl-terminated urethane prepolymer (UPH-S), one can enumerate: Sequence 1) Combine more than one polyol (HA), more than one active hydrogen group-containing compound (HB), more than one polyisocyanate (N), optionally more than one catalyst, and optionally more than one The order in which the solvents are put into the flask together; Sequence 2) Put more than one polyol (HA), one or more active hydrogen group-containing compounds (HB), optionally more than one catalyst, and optionally more than one solvent into the flask, and The order in which more than one polyisocyanate (N) is added dropwise; Step 3) Put one or more polyols (HA), one or more polyisocyanates (N), if necessary, one or more catalysts, and if necessary, one or more solvents into the flask together to make more than one After the polyisocyanate (N) reacts with more than one polyol (HA) in excess of isocyanate groups to form an isocyanate-terminated urethane prepolymer (UPN-S), add more than one active hydrogen-containing group The order of the compound (HB) and so on.

In sequence 1) and sequence 2), the higher molecular weight polyol (HA) and the lower molecular weight active hydrogen group-containing compound (HB) are simultaneously mixed with the polyisocyanate (N). In this method, there is a tendency that the reactive hydrogen group-containing compound (HB) with higher reactivity and lower molecular weight is preferentially reacted with the polyisocyanate (N) than the higher molecular weight polyol (HA) with lower reactivity. . In this case, there is a concern that a relatively low-reactivity, high-molecular-weight polyol (HA) remains in an unreacted state, causing the reaction liquid to become cloudy. In order to eliminate the relatively high molecular weight polyol (HA) remaining in an unreacted state, when the molar number of isocyanate groups is excessive relative to the total molar number of active hydrogen groups, there are concerns as follows: Cause the lower molecular weight active hydrogen group-containing compound (HB) to react with the polyisocyanate (N) to form an isocyanate group-terminated urethane prepolymer and a low molecular weight polyether polyol with high reactivity ( HB) undesired reaction, resulting in gelation of the reaction solution.

In terms of easy control of the reaction, sequence 3) is preferred. The polymerization using this sequence includes the step of reacting more than one polyol (HA) with more than one polyisocyanate (N) in a ratio of excess isocyanate groups to form an isocyanate group-terminated urethane prepolymer (UPN) ; And the step of reacting the obtained isocyanate group-terminated urethane prepolymer (UPN) with more than one active hydrogen group-containing compound (HB).

In step 3), in a state where the lower molecular weight active hydrogen group-containing compound (HB) does not coexist, first only the lower reactivity higher molecular weight polyol (HA) is reacted with the polyisocyanate (N), and then The obtained isocyanate group-terminated urethane prepolymer (UPN) is reacted with an active hydrogen group-containing compound (HB). In this method, the gelation and cloudiness of the reaction liquid can be suppressed, and the desired hydroxyl terminal urethane prepolymer (UPH-S) can be synthesized stably. Therefore, the hydroxyl-terminated urethane prepolymer (UPH-S) is preferably a reaction product of an isocyanate-terminated urethane prepolymer (UPN) and an active hydrogen-containing compound (HB). Isocyanate terminal urethane prepolymer (UPN) is a reaction product of polyol (HA) and polyisocyanate (N). In sequence 3), one or more polyisocyanates (N) preferably include isophorone diisocyanate (IPDI). In this case, the reaction can be easily controlled and the desired hydroxyl terminal urethane prepolymer (UPH-S) can be synthesized stably.

(Multifunctional isocyanate compound (I)) As the polyfunctional isocyanate compound (I), known ones can be used, and compounds exemplified in the form of polyisocyanate (N) as the raw material of the hydroxyl terminal urethane prepolymer (UPH) (specifically, aromatic Polyisocyanates, aliphatic polyisocyanates, aromatic aliphatic polyisocyanates, alicyclic polyisocyanates, and trimethylolpropane adducts/biuret/urethane/trimers).

(Plasticizer (P)) The adhesive of the present invention may contain one or more plasticizers (P) as necessary. The plasticizer (P) can function as a diluent together with the solvent. By adding a plasticizer (P) to the adhesive of the present invention, it is preferable to achieve a low viscosity even with a high solid content concentration. When the adhesive of the present invention contains a plasticizer (P), the adhesive layer has good wettability with respect to adherends such as glass, and when the adhesive sheet is attached to the adherend, a bubble suppression roll can also be obtained The effect of entering the attachment interface. The amount of the plasticizer (P) relative to 100 parts by mass of the hydroxyl terminal urethane prepolymer (UPH) is preferably 0 parts by mass to 200 parts by mass, more preferably 20 parts by mass to 200 parts by mass. The amount of the plasticizer (P) relative to 100 parts by mass of the hydroxyl-terminated urethane prepolymer (UPH) is particularly preferably 50 parts by mass to 200 parts by mass or 20 parts by mass to 150 parts by mass, most preferably 50 parts by mass Parts ~ 150 parts by mass.

The plasticizer (P) is not particularly limited, but from the viewpoint of compatibility with other components, etc., an organic acid ester having a molecular weight of 250 to 1,000 is preferred.

Examples of esters of monobasic acid or polybasic acid and alcohol include: isostearyl laurate, isopropyl myristate, isocetyl myristate, octyl lauryl myristate, palmitic acid Isostearyl ester, isocetyl stearate, octyl dodecyl oleate, dibutyl phthalate, dioctyl phthalate, diheptyl phthalate, phthalate Dibenzyl formate, butyl benzyl phthalate, diisodecyl adipate, diisostearyl adipate, dibutyl sebacate, diisocetyl sebacate, acetylene Tributyl citrate, tributyl trimellitate, trioctyl trimellitate, trihexyl trimellitate, trioleyl trimellitate, and triisocetyl trimellitate Ester etc.

As esters of other acids and alcohols, for example, unsaturated fatty acids such as myristic acid, oleic acid, linoleic acid, hypolinoleic acid, isopalmitic acid, and isostearic acid, or chorismic acid and ethylene glycol, Esters of alcohols such as propylene glycol, glycerin, trimethylolpropane, pentaerythritol, and sorbitol anhydride.

Examples of esters of monobasic acid or polybasic acid and polyalkylene glycol include dihexanoic acid polyethylene glycol, di-2-ethylhexanoic acid polyethylene glycol, dilauric acid polyethylene glycol, and dioleic acid. Polyethylene glycol, and adipic acid dipolyethylene glycol methyl ether, etc.

From the viewpoint of improving wettability and the like, the molecular weight (formula weight or Mn) of the organic acid ester is preferably 250 to 1,000, more preferably 400 to 900, and particularly preferably 500 to 850. If the molecular weight is 250 or more, the heat resistance of the adhesive layer becomes good. If the molecular weight is 1,000 or less, the wettability of the adhesive becomes good, and the adhesive can be effectively low in viscosity.

(Β-diketone compound (X)) The adhesive of the present invention may contain one or more β-diketone compounds (X) as necessary. The β-diketone compound (X) is not particularly limited, and examples thereof include acetone, 2,4-pentanedione, 3-methyl-2,4-pentanedione, and 2,4-hexanedione , 1,3-cyclohexanedione, 2,2-dimethyl-3,5-hexanedione, 2,4-heptanedione, 3,5-heptanedione, 2,2,6,6- Tetramethyl-3,5-heptanedione, 1,3-cycloheptanedione, 2,4-octanedione, 2,2,7-trimethyl-3,5-octanedione, 2,4 -Nonanedione, 3-methyl-2,4-nonanedione, 2-methyl-4,6-nonanedione, 1-phenyl-1,3-butanedione, and spirodecanedione, etc. . Among them, acetone and the like are preferred. The β-diketone compound (X), such as acetone, functions as a hardening retarder, and by adding it to the adhesive, the pot life can be adjusted well.

(Solvent) The adhesive of the present invention may contain more than one solvent as necessary. As the solvent, known ones can be used, and examples thereof include organic solvents such as methyl ethyl ketone, ethyl acetate, toluene, xylene, and acetone. The adhesive of the present invention has a relatively high solid content concentration, and in order to have a relatively low viscosity at the time of coating to have good coating adaptability, the amount of organic solvent used can be reduced. The content of the organic solvent in the adhesive of the present invention is preferably 20% by mass or less, more preferably 10% by mass or less, and may be 0% by mass. The amount of volatile organic compound (VOC) used in the adhesive of the present invention is small, and it is preferable in terms of environmental aspects and the like.

(Anti-deteriorating agent) The adhesive of the present invention may contain one or more anti-deteriorating agents as necessary. Thereby, it is possible to suppress the degradation of various characteristics caused by the long-term use of the adhesive layer. Examples of the anti-deterioration agent include hydrolysis-resistant agents, antioxidants, ultraviolet absorbers, and light stabilizers.

＜Hydrolysis resistance agent＞ When the adhesive layer undergoes a hydrolysis reaction under a high temperature and high humidity environment to generate carboxyl groups, in order to block the carboxyl groups, a hydrolysis-resistant agent can be used. Examples of the hydrolysis resistant agent include carbodiimide-based, isocyanate-based, oxazoline-based, and epoxy-based agents. Among them, from the viewpoint of the hydrolysis inhibitory effect, the carbodiimide system is preferred.

The carbodiimide hydrolysis inhibitor is a compound having one or more carbodiimide groups in one molecule. Examples of monocarbodiimide compounds include dicyclohexylcarbodiimide, diisopropylcarbodiimide, dimethylcarbodiimide, and diisobutylcarbodiimide. , Dioctylcarbodiimide, diphenylcarbodiimide, and naphthylcarbodiimide, etc. The polycarbodiimide compound can be produced by subjecting a diisocyanate to a decarbonation condensation reaction in the presence of a carbodiimide catalyst. Here, as the diisocyanate, for example, 4,4'-diphenylmethane diisocyanate, 3,3'-dimethoxy-4,4'-diphenylmethane diisocyanate, 3,3'- Dimethyl-4,4'-diphenylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, 3,3'-dimethyl-4,4'-diphenyl ether diisocyanate, 2 ,4-toluene diisocyanate, 2,6-toluene diisocyanate, 1-methoxyphenyl-2,4-diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and Tetramethylxylylene diisocyanate, etc. Examples of the carbodiimide catalyst include: 1-phenyl-2-phosphorene-1-oxide, 3-methyl-2-phosphorene-1-oxide, 1 -Ethyl-3-methyl-2-phosphorene-1-oxide, 1-ethyl-2-phosphorene-1-oxide, and these 3-phosphorenes Phosphonol oxides such as ene isomers, etc.

Examples of isocyanate-based hydrolysis inhibitors include 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2 ,4'-Diphenylmethane Diisocyanate, 2,2'-Diphenylmethane Diisocyanate, 3,3'-Dimethyl-4,4'-Biphenyl Diisocyanate, 3,3'-Dimethoxy -4,4'-biphenyl diisocyanate, 3,3'-dichloro-4,4'-biphenyl diisocyanate, 1,5-naphthalene diisocyanate, 1,5-tetrahydronaphthalene diisocyanate, tetrakis Methyl diisocyanate, 1,6-hexamethylene diisocyanate, dodecamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,3-cyclohexyl diisocyanate, 1,4-ring extension Hexyl diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, hydrogenated xylylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexyl Methane diisocyanate, and 3,3'-dimethyl-4,4'-dicyclohexylmethane diisocyanate, etc.

As oxazoline hydrolysis inhibitors, for example, 2,2'-o-phenylbis(2-oxazoline), 2,2'-m-phenylbis(2-oxazoline), 2,2'- P-phenylenedi (2-oxazoline), 2,2'-p-phenylenedi (4-methyl-2-oxazoline), 2,2'-m-phenylenedi (4-methyl-2-oxazole) Morpholine), 2,2'-p-phenylene (4,4'-dimethyl-2-oxazoline), 2,2'-m-phenylene (4,4'-dimethyl-2-oxazole) Morpholine), 2,2'-ethylenebis(2-oxazoline), 2,2'-tetramethylenebis(2-oxazoline), 2,2'-hexamethylenebis(2 -Oxazoline), 2,2'-octamethylenebis(2-oxazoline), 2,2'-ethylenebis(4-methyl-2-oxazoline), and 2,2 '-Diphenylene bis(2-oxazoline) and the like.

Examples of epoxy-based hydrolyzing agents include diglycidyl ethers of aliphatic glycols such as 1,6-hexanediol, neopentyl glycol, and polyalkylene glycol; sorbitol, sorbitol anhydride, and polypropylene glycol. Polyglycidyl ether of aliphatic polyhydric alcohols such as alcohol, pentaerythritol, diglycerol, glycerol, and trimethylolpropane; polyglycidyl ether of alicyclic polyhydric alcohols such as cyclohexanedimethanol; terephthalic acid Diglycidyl or polyglycidyl esters of aliphatic or aromatic polycarboxylic acids such as formic acid, isophthalic acid, naphthalenedicarboxylic acid, trimellitic acid, adipic acid, and sebacic acid; resorcinol , Bis-(p-hydroxyphenyl)methane, 2,2-bis-(p-hydroxyphenyl)propane, tris-(p-hydroxyphenyl)methane, and 1,1,2,2-tetra(p-hydroxyphenyl) ) Diglycidyl ether or polyglycidyl ether of polyphenols such as ethane; N,N-diglycidylaniline, N,N-diglycidyltoluidine, and N,N,N',N'-tetra N-glycidyl derivatives of amines such as glycidyl-bis-(p-aminophenyl)methane; triglycidyl derivatives of aminophenol; triglycidyl tris(2-hydroxyethyl) isotris Polycyanate, triglycidyl isocyanurate; o-cresol type epoxy resin and phenol novolac type epoxy resin, etc.

The addition amount of the hydrolysis resistant agent is not particularly limited. It is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 4.5 parts by mass relative to 100 parts by mass of the hydroxyl terminal urethane prepolymer (UPH) Parts, particularly preferably 0.5 parts by mass to 3 parts by mass.

＜Antioxidant＞ Examples of antioxidants include radical scavengers and peroxide decomposers. As a radical scavenger, a phenolic compound, an amine compound, etc. are mentioned. Examples of peroxide decomposers include sulfur-based compounds and phosphorus-based compounds.

Examples of phenolic compounds include: 2,6-di-tert-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-tert-butyl-4-ethylphenol, β -(3,5-Di-tert-butyl-4-hydroxyphenyl) stearyl propionate, 2,2'-methylene bis(4-methyl-6-tert-butylphenol), 2 ,2'-methylenebis(4-ethyl-6-tertiary butylphenol), 4,4'-thiobis(3-methyl-6-tertiary butylphenol), 4,4' -Butylene bis (3-methyl-6-tert-butylphenol), 3,9-bis[1,1-dimethyl-2-[β-(3-tert-butyl-4-hydroxy- 5-methylphenyl)propionyloxy]ethyl]2,4,8,10-tetraoxaspiro[5,5]undecane, phenylpropionic acid, 3,5-bis(1,1- Dimethylethyl)-4-hydroxy-, C7-C9 side chain alkyl ester, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 1,3,5-Trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, tetra-(methylene-3-(3', 5'-Di-tertiary butyl-4'-hydroxyphenyl)propionate]methane, bis[3,3'-bis-(4'-hydroxy-3'-tertiary butylphenyl)butyric acid ] Glycol ester, 1,3,5-tris(3',5'-di-tert-butyl-4'-hydroxybenzyl)-S-triazine-2,4,6-(1H,3H , 5H) Triketone, and tocopherol, etc.

Examples of sulfur-based antioxidants include 3,3'-thiodipropionate dilauryl ester, 3,3'-thiodipropionate dimyristyl ester, and 3,3'-thiodipropionate Distearyl acid ester and so on.

As the phosphorus compound, for example, triphenyl phosphite, diphenyl isodecyl phosphite, 4,4'-butylene-bis(3-methyl-6-tert-butylphenyl di-deca Trialkyl) phosphite, cyclic neopentyl tetrayl bis(octadecyl phosphite), tris(nonylphenyl) phosphite, tris(monononylphenyl) phosphite, three (Dinonylphenyl) phosphite, diisodecyl pentaerythritol diphosphite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-(3,5 -Di-tert-butyl-4-hydroxybenzyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-decyloxy-9,10-dihydro -9-oxa-10-phosphaphenanthrene, tris(2,4-di-tert-butylphenyl) phosphite, cyclic neopentanetetrayl bis(2,4-di-tert-butyl) Phenyl) phosphite, cyclic neopentyl tetrayl bis(2,6-di-tert-butyl-4-methylphenyl) phosphite, and 2,2-methylene bis(4, 6-Di-tert-butylphenyl) octyl phosphite and the like.

The use of antioxidants prevents thermal degradation of the hydroxyl-terminated urethane prepolymer (UPH). In addition, it can effectively suppress the bleeding of the plasticizer (P) from the adhesive layer when the plasticizer (P) is used. The amount of antioxidant added is not particularly limited. It is preferably 0.01 parts by mass to 5 parts by mass, more preferably 0.1 parts by mass to 3 parts by mass relative to 100 parts by mass of the hydroxyl-terminated urethane prepolymer (UPH) , Particularly preferably 0.2 parts by mass to 2 parts by mass.

As the antioxidant, from the viewpoint of stability and antioxidant effect, it is preferable to use one or more phenolic compounds as a radical scavenger, and it is more preferable to use one or more phenolic compounds as a radical scavenger in combination with One or more kinds of phosphorus-based compounds as peroxide decomposers. In addition, as the antioxidant, it is particularly preferable to use a phenol-based compound as a radical scavenger and a phosphorus-based compound as a peroxide decomposer in combination, and to use these antioxidants in combination with the hydrolysis-resistant agent.

＜Ultraviolet absorber＞ Examples of ultraviolet absorbers include benzophenone-based compounds, benzotriazole-based compounds, salicylic acid-based compounds, oxaniline-based compounds, cyanoacrylate-based compounds, and triazine-based compounds. The addition amount of the ultraviolet absorber is not particularly limited, and it is preferably 0.01 to 3 parts by mass, more preferably 0.1 to 2.5 parts by mass relative to 100 parts by mass of the hydroxyl-terminated urethane prepolymer (UPH) Parts, particularly preferably 0.2 parts by mass to 2 parts by mass.

＜Light stabilizer＞ Examples of the light stabilizer include hindered amine-based compounds and hindered piperidine-based compounds. The addition amount of the light stabilizer is not particularly limited. It is preferably 0.01 to 2 parts by mass, more preferably 0.1 to 1.5 parts by mass relative to 100 parts by mass of the hydroxyl-terminated urethane prepolymer (UPH) Parts, particularly preferably 0.2 part by mass to 1 part by mass.

(Antistatic agent (AS agent)) The adhesive of the present invention may contain more than one antistatic agent (AS agent) as necessary. Examples of the antistatic agent include inorganic salts, polyol compounds, ionic liquids, ionic solids, and surfactants. Among them, ionic liquids and/or ionic solids are preferred. In addition, "ionic liquid" is also called normal temperature molten salt, and is a salt having fluidity at 25°C.

Examples of inorganic salts include sodium chloride, potassium chloride, lithium chloride, lithium perchlorate, ammonium chloride, potassium chlorate, aluminum chloride, copper chloride, ferrous chloride, ferric chloride, and ammonium sulfate , Potassium nitrate, sodium nitrate, sodium carbonate, and sodium thiocyanate.

Examples of the polyol compound include propylene glycol, butylene glycol, hexylene glycol, polyethylene glycol, trimethylolpropane, and pentaerythritol.

As the ionic liquid containing imidazolium ions, for example, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imidine, 1,3-dimethylimidazolium bis(trifluoromethane) Fluoromethylsulfonyl)imide, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, and the like.

Examples of ionic liquids containing pyridinium ions include: 1-methylpyridinium bis(trifluoromethylsulfonyl)imide, 1-butylpyridinium bis(trifluoromethylsulfonyl)imide Imine, 1-hexylpyridinium bis(trifluoromethylsulfonyl)imine, 1-octylpyridinium bis(trifluoromethylsulfonyl)imine, 1-hexyl-4-methyl Pyridium bis(trifluoromethylsulfonyl)imide, 1-hexyl-4-methylpyridinium hexafluorophosphate, 1-octyl-4-methylpyridinium bis(trifluoromethylsulfonyl) Base) imidimide, 1-octyl-4-methylpyridinium bis(fluorosulfonyl)imid, 1-methylpyridinium bis(perfluoroethylsulfonyl)imid, and 1 -Methylpyridinium bis(perfluorobutylsulfonyl)imidine and the like.

As the ionic liquid containing ammonium ions, for example, trimethylheptylammonium bis(trifluoromethanesulfonyl)imidine, 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)imide, and tri-n-butylmethylammonium bis(trifluoromethanesulfonyl)imide, etc.

In addition, commercially available ionic liquids such as pyrrolidinium salt, phosphonium salt, and sulfonium salt can be suitably used.

The ionic solid is a salt of a cation and an anion similarly to an ionic liquid, but it is a substance showing a solid state at 25°C under normal pressure. As the cation, for example, an alkali metal ion, a phosphonium ion, a pyridinium ion, and an ammonium ion are preferable.

Examples of ionic solids containing alkali metal ions include lithium bisfluorosulfonylimide, lithium bistrifluoromethyl sulfonylimide, lithium bispentafluoroethyl sulfonylimide, and lithium Diheptafluoropropyl sulfonylimide, lithium bisnonane fluorobutane sulfonylimide, sodium bisfluorosulfonylimide, sodium bistrifluoromethyl sulfonylimide, sodium Dipentafluoroethyl sulfonylimide, sodium bisheptafluoropropyl sulfonylimide, sodium bis-nonane fluorobutyl sulfonylimide, potassium bisfluorosulfonylimide, potassium Bistrifluoromethanesulfonylimide, potassium bispentafluoroethylsulfonylimide, potassium bisheptafluoropropyl sulfonylimide, and potassium bisnonanefluorobutanesulfonylimide Imines and so on.

Examples of ionic solids containing phosphonium ions include: tetrabutylphosphonium bisfluorosulfonylimide, tetrabutylphosphonium bistrifluoromethyl sulfonylimide, tetrabutylphosphonium bispentafluoroethane Sulfonamide, tetrabutylphosphonium bisheptafluoropropyl sulfonamide, tetrabutylphosphonium bisnonane fluorobutyl sulfonamide, tributyl hexadecyl phosphonium bis Fluorosulfonylimide, tributylhexadecylphosphonium bistrifluoromethyl sulfonylimide, tributylhexadecylphosphonium bispentafluoroethyl sulfonylimide, tributyl Hexadecyl phosphonium bisheptafluoropropyl sulfonylimide, tributyl hexadecyl phosphonium bisnonane fluorobutyl sulfonylimide, tetraoctyl phosphonium bisfluoro sulfonylimide Amine, tetraoctylphosphonium bis(trifluoromethyl)sulfonylimide, tetraoctylphosphonium bispentafluoroethyl sulfonylimide, tetraoctylphosphonium bisheptafluoropropyl sulfonamide, And tetraoctyl phosphonium dinonane fluorobutyl sulfonyl imide and so on.

As the ionic solid containing pyridinium ion, for example, 1-hexadecyl-4-methylpyridinium bisfluorosulfonylimide, 1-hexadecyl-4-methylpyridinium bis Trifluoromethylsulfonylimide, 1-hexadecyl-4-methylpyridinium bispentafluoroethylsulfonylimide, 1-hexadecyl-4-methylpyridinium bis Heptafluoropropyl sulfonylimide, 1-hexadecyl-4-methylpyridinium bisnonane fluorobutyl sulfonylimide and the like.

Examples of ionic solids containing ammonium ions include: lauryl trimethyl ammonium chloride, tributyl methyl bis trifluoromethyl sulfonylimide, and tributyl methyl bis pentafluoroethyl sulfonylimide. Amine, tributylmethylbisheptafluoropropyl sulfonylimide, tributylmethyl bisnonane fluorobutyl sulfonylimide, octyltributyl bistrifluoromethyl sulfonylimide, Octyl tributyl bis pentafluoroethyl sulfonylimide, octyl tributyl bis heptafluoropropyl sulfonylimide, octyl tributyl bisnonane fluorobutyl sulfonylimide Amine, tetrabutylbisfluorosulfonylimide, tetrabutylbistrifluoromethyl sulfonylimide, tetrabutylbispentafluoroethyl sulfonylimide, tetrabutylbisheptafluoro Propyl sulfonylimide, and tetrabutyl bisnonane fluorobutyl sulfonylimide, etc.

In addition, well-known ionic solids in which the cation is a pyrrolidinium ion, an imidazolium ion, a sulfonium ion, etc. can be suitably used.

Surfactants are classified into low-molecular-weight surfactants and high-molecular-weight surfactants. Each type has nonionic, anionic, cationic, and amphoteric types.

Examples of nonionic low-molecular-weight surfactants include: glycerin fatty acid esters, polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene alkylamines, polyoxyethylene Ethylene alkyl amine fatty acid ester, and fatty acid diethanol amide, etc. Examples of anionic low-molecular-weight surfactants include alkylsulfonates, alkylbenzenesulfonates, and alkyl phosphates. Examples of cationic low-molecular-weight surfactants include tetraalkylammonium salts and trialkylbenzylammonium salts. Examples of the amphoteric low-molecular-weight surfactant include alkyl betaine and alkyl imidazolium betaine.

Examples of nonionic polymer surfactants include polyether ester amide type, ethylene oxide-epichlorohydrin type, and polyether ester type. Examples of anionic polymer surfactants include polystyrene sulfonic acid type and the like. Examples of cationic polymer surfactants include quaternary ammonium salt group-containing acrylate polymer types. Examples of amphoteric polymer surfactants include amino acid type amphoteric surfactants such as higher alkylaminopropionates, higher alkyl dimethyl betaine, and higher alkyl dihydroxyethyl betaine. Betaine type amphoteric surfactants, etc.

The addition amount of the antistatic agent is preferably 0.01 parts by mass to 10 parts by mass, and more preferably 0.03 parts by mass to 5 parts by mass relative to 100 parts by mass of the hydroxyl-terminated urethane prepolymer (UPH).

(Leveling agent) The adhesive of the present invention may contain a leveling agent as necessary. By adding a leveling agent, the leveling of the adhesive layer can be improved. Examples of the leveling agent include acrylic leveling agents, fluorine leveling agents, and silicone leveling agents. From the viewpoint of suppressing the adhesion of the adhesive sheet after re-peeling, acrylic acid is preferred. Department leveling agent, etc.

The weight average molecular weight (Mw) of the leveling agent is not particularly limited, but is preferably 500 to 20,000, more preferably 1,000 to 15,000, and particularly preferably 2,000 to 10,000. If Mw is 500 or more, the amount of vaporization from the coating layer during heating and drying of the coating layer can suppress the surrounding contamination to a sufficiently small amount. If Mw is 20,000 or less, the effect of improving the leveling properties of the adhesive layer is effectively expressed.

The amount of the leveling agent added is not particularly limited. From the viewpoint of suppressing the contamination of the adherend after peeling off the adhesive sheet and improving the leveling of the adhesive layer, compared to the hydroxyl-terminated urethane prepolymer (UPH ) 100 parts by mass, preferably 0.001 parts by mass to 2 parts by mass, more preferably 0.01 parts by mass to 1.5 parts by mass, particularly preferably 0.1 parts by mass to 1 part by mass.

(Other optional ingredients) The adhesive of the present invention may contain other optional components as needed within a range that does not impair the effects of the present invention. Examples of other optional components include: catalysts, resins other than urethane resins, fillers (talc, calcium carbonate, and titanium oxide, etc.), metal powders, colorants (pigments, etc.), foils , Softener, conductive agent, silane coupling agent, lubricant, anticorrosive agent, heat stabilizer, weather stabilizer, polymerization inhibitor, and defoamer, etc.

(Allocation ratio) The adhesive of the present invention contains one or more hydroxyl-terminated urethane prepolymers (UPH) and one or more polyfunctional isocyanate compounds (I) as essential components, and further contains one or more optional components as necessary. The blending ratios are not particularly limited, and preferable blending ratios are as follows. The amount of one or more polyfunctional isocyanate compounds (I) relative to 100 parts by mass of one or more hydroxyl terminal urethane prepolymers (UPH) is preferably 1 part by mass to 30 parts by mass, more preferably 3 parts by mass ～20 parts by mass. If the amount of one or more polyfunctional isocyanate compounds (I) is 3 parts by mass or more, the cohesive force of the adhesive layer becomes good, and if it is 20 parts by mass or less, the pot life becomes good.

(Method of manufacturing adhesive) The manufacturing method of the adhesive of this invention is not specifically limited. To the solution of the hydroxyl-containing terminal urethane prepolymer synthesized by one-stage or multi-stage copolymerization, one or more polyfunctional isocyanate compounds (I) and optionally one or more optional components are added and mixed Thus, the adhesive of the present invention can be manufactured.

[Adhesive sheet] The adhesive sheet of the present invention includes a base sheet and an adhesive layer containing a cured product of the adhesive of the present invention. The adhesive layer can be formed on one side or both sides of the substrate sheet. If necessary, a release sheet can be used to cover the exposed surface of the adhesive layer. Furthermore, when the adhesive sheet is attached to the adherend, the release sheet can be peeled off.

Fig. 1 shows a schematic cross-sectional view of the adhesive sheet according to the first embodiment of the present invention. In FIG. 1, the symbol 10 is an adhesive sheet, the symbol 11 is a base sheet, the symbol 12 is an adhesive layer, and the symbol 13 is a release sheet. The adhesive sheet 10 is a single-sided adhesive sheet having an adhesive layer formed on one side of a base sheet. Fig. 2 shows a schematic cross-sectional view of an adhesive sheet according to a second embodiment of the present invention. In FIG. 2, the symbol 20 is an adhesive sheet, the symbol 21 is a base sheet, the symbols 22A and 22B are adhesive layers, and the symbols 23A and 23B are release sheets.

The substrate sheet is not particularly limited, and examples thereof include resin sheets, paper, and metal foils. The base material sheet may be a laminated sheet formed by layering any one or more layers on at least one area of these base material sheets. The surface of the substrate sheet on the side where the adhesive layer is formed may be subjected to easy bonding treatments, such as corona discharge treatment and anchor coating agent coating, if necessary.

The constituent resin of the resin sheet is not particularly limited, and examples include: ester resins such as polyethylene terephthalate (PET); polyethylene (PE) and polypropylene (PP), etc. Olefin resins; vinyl resins such as polyvinyl chloride; amide resins such as nylon 66; urethane resins (including foams); combinations of these, etc. The thickness of the resin sheet other than the polyurethane sheet is not particularly limited, but is preferably 15 μm to 300 μm. The thickness of the polyurethane sheet (including the foam) is not particularly limited, but is preferably 20 μm to 50,000 μm.

The paper is not particularly limited, and examples thereof include plain paper, coated paper, and coated paper. The constituent metal of the metal foil is not particularly limited, and examples thereof include aluminum, copper, and combinations of these.

There is no restriction|limiting in particular as a peeling sheet, The well-known peeling sheet which performed the well-known peeling process, such as a peeling agent coating, on the surface of a base material sheet, such as a resin sheet or paper, can be used.

The adhesive sheet can be manufactured by a known method. First, the adhesive of the present invention is applied to the surface of a substrate sheet to form a coating layer containing the adhesive of the present invention. A known method can be applied to the coating method, and examples thereof include a roll coater method, a chipped wheel coater method, a die coater method, a reverse coater method, a screen printing method, and a gravure coater method. Next, the coating layer is dried and cured to form an adhesive layer of a cured product containing the adhesive of the present invention. The heating and drying temperature is not particularly limited, but is preferably about 60°C to 150°C. The thickness of the adhesive layer (thickness after drying) varies depending on the application, but is preferably 0.1 μm to 200 μm. Secondly, if necessary, the release sheet is attached to the exposed surface of the adhesive layer by a known method. In this way, a single-sided adhesive sheet can be manufactured. By performing the above operations on both sides, a double-sided adhesive sheet can be manufactured.

Contrary to the method described above, the adhesive of the present invention is applied to the surface of the release sheet to form a coating layer containing the adhesive of the present invention, and then the coating layer is dried and hardened to form a coating layer containing the adhesive of the present invention. The adhesive layer of the hardened material of the adhesive is laminated on the exposed surface of the adhesive layer.

The manufacturing method of the adhesive sheet preferably includes: a coating step of applying an adhesive on the substrate sheet; a heating step of heating and drying the formed coating layer to form an adhesive layer containing a hardened substance of the adhesive; In the winding step, the obtained adhesive sheet is wound around the core to form the form of the adhesive sheet roll; and the curing step is to cure the adhesive sheet roll.

As explained above, according to the present invention, it is possible to provide a solution of a hydroxyl terminal urethane prepolymer for an adhesive with a reduced usage amount of an organic solvent, a relatively high solid content concentration, and a relatively low viscosity. According to the present invention, it is possible to provide a solution of a hydroxyl-terminated terminal urethane prepolymer for an adhesive, that is, the solid content concentration is 80% by mass or more, preferably 85% by mass or more, and particularly preferably 90% by mass Above, 95% by mass or more is best, and the viscosity at 25°C after being left at 25°C for 1 hour shortly after preparation is 8000 mPa·s or less, preferably 7000 mPa·s or less, and more preferably 6000 mPa·s or less, particularly preferably 5000 mPa·s or less.

In addition, according to the present invention, it is possible to provide an adhesive with a reduced usage of organic solvents, a relatively high solid content concentration, and a relatively low viscosity at the time of application to have good application adaptability. According to the present invention, an adhesive can be provided in which the solid content concentration is preferably 70% by mass or more, more preferably 80% by mass or more, particularly preferably 90% by mass or more, and is allowed to stand at 25°C shortly after preparation The viscosity at 25°C after 3 hours is preferably 8000 mPa·s or less, more preferably 7000 mPa·s or less, and particularly preferably 5000 mPa·s or less. Since the viscosity at 25°C after being allowed to stand at 25°C for 3 hours shortly after preparation is within the above range, good coating adaptability can be obtained.

In order to achieve high solid content concentration and low viscosity of the adhesive, the hydroxyl-terminated urethane prepolymer (UPH) used in the present invention is preferably higher than the previous general hydroxyl-terminated urethane prepolymer. Said as low molecular weight. In order to achieve high solid content concentration and low viscosity of the adhesive, and at the same time to make the initial hardenability of the adhesive good, the hydroxyl-terminated urethane prepolymer (UPH) is preferably used as a variety of active hydrogen group-containing compounds ( HX), the hydroxyl-terminated urethane prepolymer (UPH-S) of the reaction product with more than one polyisocyanate (N), the multiple active hydrogen group-containing compounds (HX) containing Mn of 1000 or more, It is preferably one or more polyols (HA) of 1000 to 7000, and one or more active hydrogen group-containing compounds (HB) of which Mn is less than 1000, preferably 50 to 900.

By adjusting the mass ratio of more than one polyol (HA) as a higher molecular weight component to more than one polyisocyanate (N), the number average molecular weight (UPH) of the hydroxyl-terminated urethane prepolymer (UPH) can be adjusted. Mn) is relatively small, achieving high solid content concentration and low viscosity of the adhesive. Generally speaking, since the lower molecular weight hydroxy-terminal urethane prepolymer (UPH) has a tendency of poor initial hardening, the use of a lower molecular weight active hydrogen-containing compound (HB) as the hydroxy terminal One of the raw materials of urethane prepolymer (UPH), which can improve the initial hardenability. Furthermore, it is preferable to use an active hydrogen group-containing compound (HB) containing a primary hydroxyl group having moderate reactivity, so that the pot life and initial hardenability can be improved. If the pot life of the adhesive is good, the viscosity of the adhesive will not become too high until the adhesive is applied to the substrate sheet, and uniform application of the adhesive can be achieved. If the initial curability of the adhesive is good, the coating layer or the adhesive layer will not be easily affected by the hot air during the heating and drying of the coating layer, or the mechanical stress received during the winding and curing of the adhesive sheet obtained after the heating and drying. It can inhibit the appearance of defects such as core step marks, orange peel defects, and curling in the adhesive layer.

In addition to the aforementioned effects, by using a higher molecular weight polyol (HA) as one of the raw materials of the hydroxyl terminal urethane prepolymer (UPH), the wettability improvement effect of the adhesive layer can be obtained. In addition, by using a lower molecular weight active hydrogen group-containing compound (HB) as one of the raw materials of the hydroxyl terminal urethane prepolymer (UPH), the effect of improving the repeelability of the adhesive layer can be obtained. If the wettability of the adhesive layer is good, it is possible to prevent bubbles from being drawn into the attachment interface when the adhesive sheet is attached to an adherend such as glass. If the repeelability of the adhesive layer is good, it is possible to effectively suppress contamination of the adherend in which the adhesive component remains on the surface of the adherend after the repeeling of the adhesive sheet.

[use] The adhesive sheet of the present invention can be used in the form of tape, label, sheet, double-sided tape, and the like. The adhesive sheet of the present invention can be preferably used as a surface protection sheet, a cosmetic sheet, an anti-slip sheet, and the like. Flat panel displays such as liquid crystal displays (LCD) and organic electroluminescence displays (OELD), and touch panel displays combining the flat panel displays and touch panels are widely used in televisions (TV), personal computers (PC), In electronic equipment such as mobile phones and portable information terminals. The adhesive sheet of the present invention can be preferably used as flat panel displays and touch panel displays (these are collectively referred to as "displays"), and substrates (glass substrates, and glass substrates) that are manufactured or used in these manufacturing steps. A surface protection sheet for ITO (glass substrate, etc.) with an indium tin oxide (ITO) film formed on a glass substrate and optical components. [Example]

Hereinafter, manufacturing examples, examples of the present invention, and comparative examples will be described. In addition, in the following description, unless otherwise specified, "parts" means parts by mass, "%" means mass%, and "RH" means relative humidity.

[Evaluation Items and Evaluation Methods] The evaluation items and evaluation methods are as follows. (Mn, Mw) The number average molecular weight (Mn) and weight average molecular weight (Mw) of the urethane prepolymer are determined by the gel permeation chromatography (GPC) method. The measurement conditions are as follows. In addition, Mn and Mw are all polystyrene conversion values. <Measurement conditions> Device: SHIMADZU Prominence (manufactured by Shimadzu Manufacturing Co., Ltd.), Column: Connect two TSKgel GMH manufactured by TOSOH in series, Detector: Differential refractive index detector (RID-10A), Solvent: Tetrahydrofuran (THF), Flow rate: 1 mL/min, Solvent temperature: 40℃, Sample concentration: 0.1%, Sample injection volume: 100 μL.

(Viscosity at 25°C) The viscosity of the urethane prepolymer-containing solution, the polyol-containing solution, and the adhesive at 25°C is measured by placing the sample in a glass bottle with a lid and immersing the glass bottle at a constant temperature of 25°C Take it out of the water tank after a predetermined period of time, and use a type B viscometer ("TVB10 type viscometer" manufactured by Toki Sangyo Co., Ltd.) for implementation. For the urethane prepolymer-containing solution and the polyol-containing solution, immediately after preparation, put it into a glass bottle with a lid and immerse it in a constant temperature water tank at 25°C, and then perform the viscosity measurement after 1 hour . For the adhesive, put it into a glass bottle with a lid immediately after preparation, and immerse it in a constant temperature water tank at 25°C, and perform the measurement after 3 hours. The viscosity after 3 hours shortly after preparation is assumed to be the "viscosity at the time of application". Furthermore, in the actual manufacturing method of the adhesive sheet, the time from shortly after the preparation of the adhesive to the application is not particularly limited. From the viewpoint of optimizing the viscosity at the time of application of the adhesive, it is preferable Within 6 hours, more preferably within 3 hours.

(Solid content concentration) The solid content of the urethane prepolymer-containing solution, the polyol-containing solution, and the adhesive is determined by heating and drying about 1 g of the sample at 120°C for 20 minutes. The quality changes to find out.

(VOC reduction effect of adhesive) The solid content concentration of the adhesive was measured by the method, and the VOC reduction effect of the adhesive was evaluated. The higher the solid content concentration, the lower the amount of organic solvent used, and the higher the reduction effect of volatile organic compounds (VOC). The evaluation criteria are as follows. ◎: The solid content concentration is 90% by mass or more, which is excellent. ○: The solid content concentration is 80% by mass or more and less than 90% by mass, which is good. △: The solid content concentration is 70% by mass or more and less than 80% by mass, which is practical. ×: The solid content concentration is less than 70% by mass, which is not practical.

(Applicable period) The adhesive shortly after preparation was put into a glass bottle with a lid, the glass bottle was immersed in a constant temperature water bath at 25° C., and the viscosity was measured after 1 hour and 6 hours after the start of dipping. The viscosity increase rate (viscosity after 6 hours/1 hour [times]) after 6 hours was calculated relative to that after 1 hour. The evaluation criteria are as follows. ◎: The viscosity increase rate is less than 200%, which is excellent. ○: The viscosity increase rate is 200% or more and less than 300%, which is good. △: The viscosity increase rate is 300% or more and less than 400%, which is practical. ×: The viscosity increase rate is 400% or more, which is not practical.

(Initial hardening) In each example of Example 1 to Example 54, Comparative Example 1 to Comparative Example 4, the adhesive sheet obtained by coating the adhesive on the base sheet and drying it was prepared to be cured in an environment of 23°C-50%RH Samples for 3 hours (curing adhesive sheets for 3 hours) and samples cured for 120 hours at 23°C-50%RH (adhesive sheets curing for 120 hours). For each sample, the gel fraction (mass %) was calculated as follows. From the adhesive sheet after curing for a predetermined time, a test piece with a width of 30 mm and a length of 100 mm was cut out and attached to a SUS net (aperture: 0.077 mm, wire diameter: 0.05 mm). After immersing in ethyl acetate and extracting at 50°C for 24 hours, it was dried at 100°C for 30 minutes, and the gel fraction (mass %) was calculated based on the following formula (1). Gel fraction (mass%)=(G2/G1)×100 ... (1) In the above formula, each symbol represents the following parameters. G1: The quality of the adhesive layer before extraction with ethyl acetate, G2: The quality of the adhesive layer after extraction with ethyl acetate and drying. Furthermore, the gel fraction change rate between curing for 3 hours and curing for 120 hours was calculated based on the following formula (2). Change rate of gel fraction (%)=(H1/H2)×100...(2) In the above formula, each symbol represents the following parameters. H1: The gel fraction of the adhesive layer of the adhesive sheet cured for 3 hours, H2: The gel fraction of the adhesive layer of the adhesive sheet cured for 120 hours. The evaluation criteria are as follows. ○: The gel fraction change rate is 70% or more, which is good. △: The gel fraction change rate is 30% or more and less than 70%, which is practical. ×: The gel fraction change rate is less than 30%, which is not practical.

(Wettability) In each example of Example 1 to Example 54, Comparative Example 1 to Comparative Example 4, the adhesive sheet obtained by coating the adhesive on the base sheet and drying it was cured at a temperature of 23℃-50%RH for 120 After hours, a test piece with a width of 50 mm and a length of 100 mm was cut out from the adhesive sheet, and after being left in an environment of 23° C.-50% RH for 30 minutes, the peeling sheet was peeled from the test piece. One end in the longitudinal direction of the test piece from which the release sheet was peeled was fixed to the end of the glass plate, and the other end, which was not fixed, was lifted from the surface of the glass plate to a height of 5 cm by hand. Release your hand in this state, and measure the time until the entire adhesive layer (100 mm in length) adheres to the surface of the glass plate. The evaluation criteria are as follows. ○: The time until the entire adhesive layer is in close contact is less than 3 seconds, which is good. △: The time until the entire adhesive layer is brought into close contact is 3 seconds or more and less than 6 seconds, which is practical. ×: The time until the entire adhesive layer is brought into close contact is 6 seconds or more, which is not practical.

(Re-peelability) In each example of Example 1 to Example 54, Comparative Example 1 to Comparative Example 4, the adhesive sheet obtained by coating the adhesive on the base sheet and drying it was cured at a temperature of 23℃-50%RH for 120 After hours, two test pieces with a width of 70 mm and a length of 100 mm were cut out from the adhesive sheet. Regarding the two test pieces, the release sheet was peeled off under an environment of 23°C-50%RH, and a sodium hydroxide glass plate was attached to the surface of the exposed adhesive layer, and pressure-bonded with a laminator. The two laminates obtained were placed in an oven set at 60° C.-90% RH for 72 hours (condition 1) and 120 hours (condition 2), respectively. After heating in an oven for a predetermined period of time, the two laminates were taken out separately, and after air cooling for 3 hours in an environment of 23°C-50%RH, the adhesive sheet was peeled from the glass plate, and the repeelability was evaluated by visual observation. The evaluation criteria are as follows. ○: Under all conditions, no adhesive layer component adheres to the glass surface at all, which is excellent. △: Under condition 1, no adhesive layer component adheres to the glass surface at all, but under condition 2, the adhesive layer component adheres to the glass surface, which is practical. ×: Under all conditions, the adhesive layer component is attached to the glass surface, which is not practical.

[material] The materials used are as follows. <Polyol (HA) with a number average molecular weight (Mn) of 1000 or more> (HA-1): Kuraray polyol P-1010 (abbreviation in the table: P-1010), manufactured by Kuraray (KURARAY) company, bifunctional polyester polyol, Mn is 1000, hydroxyl number is 2, hydroxyl value Is 112, (HA-2): Kuraray polyol F-3010 (abbreviation in the table: F-3010), manufactured by Kuraray (KURARAY) company, trifunctional polyester polyol, Mn is 3000, hydroxyl number is 3, hydroxyl value Is 56, (HA-3): PEG-1000, manufactured by Sanyo Chemical Co., Ltd., bifunctional polyether polyol (polyethylene glycol), Mn is 1000, hydroxyl number is 2, hydroxyl valence is 112, (HA-4): Poly bd, manufactured by Idemitsu Kosan Co., Ltd., bifunctional polyolefin polyol, Mn is 2800, hydroxyl number is 2, hydroxyl valence is 40, (HA-5): PP-2000, manufactured by Sanyo Chemical Co., Ltd., bifunctional polyether polyol, Mn is 2000, hydroxyl number is 2, hydroxyl value is 56, (HA-6): Excenol 5030 (abbreviation in the table: EXCE5030), manufactured by Asahi Glass Company, trifunctional polyether polyol, Mn is 5100, hydroxyl number is 3, hydroxyl value is 33, (HA-7): Excenol 851 (abbreviation in the table: EXCE851), manufactured by Asahi Glass Company, trifunctional polyether polyol, Mn of 6700, hydroxyl number of 3, and hydroxyl value of 25.

(HA-8): Preminol S4013F (abbreviation in the table: PREM S4013F), manufactured by Asahi Glass Company, bifunctional polyether polyol, Mn is 12000, hydroxyl number is 2, and hydroxyl value is 9, (HA-9): Preminol S3011 (abbreviation in the table: PREM S3011), manufactured by Asahi Glass Company, trifunctional polyether polyol, Mn is 10000, hydroxyl number is 3, and hydroxyl value is 17.

<Active hydrogen group-containing compounds (HB) with number average molecular weight (Mn) less than 1,000> (HB-1): Ethylene glycol (EG), only contains first-grade hydroxyl, (HB-2): 1,5-pentanediol, only contains primary hydroxyl, (HB-3): 2-Ethyl-1,3-hexanediol (also known as 1,3-octanediol), including primary and secondary hydroxyl groups, (HB-4): PPG200 (the number indicates Mn, and the same for PEG), polypropylene glycol, manufactured by Sanyo Chemical Co., Ltd., contains only secondary hydroxyl groups, (HB-5): PEG300, polyethylene glycol, manufactured by Sanyo Chemical Co., Ltd., containing only first-grade hydroxyl, (HB-6): PEG600, polyethylene glycol, manufactured by Sanyo Chemical Co., Ltd., containing only primary hydroxyl, (HB-7): Glycerin, including primary and secondary hydroxyl groups, (HB-8): Trimethylolpropane (TMP), only contains first-grade hydroxyl, (HB-9): 1-Methylamino-2,3-propanediol (MAPD), manufactured by Tokyo Chemical Industry Co., Ltd., polyol containing trifunctional amine group, Mn of 105, containing primary hydroxyl, secondary hydroxyl, and Amine group.

＜Polyisocyanate (N)＞ (N-1): Isophorone diisocyanate (IPDI), manufactured by Tokyo Chemical Industry Co., Ltd., (N-2): Hexamethylene diisocyanate (HDI), manufactured by Tokyo Chemical Industry Co., Ltd., (N-3): Toluene diisocyanate (a mixture of 2,4-toluene diisocyanate (80% by mass) and 2,6-toluene diisocyanate (20% by mass)) (TDI), manufactured by Tosoh Corporation.

＜Organic solvent (B)＞ (B-1): Ethyl acetate, manufactured by Daicel.

＜Plasticizer (P)＞ (P-1): Maleate plasticizer, dioctyl maleate (DOM), manufactured by Dahachi Chemical Company, (P-2): Orthophosphate plasticizer, tris(2-ethylhexyl) phosphate (TOP), manufactured by Dahachi Chemical Company, (P-3): Polyether ester plasticizer, RS-700, manufactured by ADEKA.

＜Antioxidant (D)＞ (D-1): IRGANOX 1135, manufactured by BASF.

＜β-Diketone compound (X) (hardening retarder)＞ (X-1): Acetone, manufactured by Tokyo Chemical Industry Co., Ltd.

＜Antistatic agent (AS agent) (F)＞ (F-1): Elexcel AS-804, manufactured by First Industrial Pharmaceutical Company.

＜Multifunctional isocyanate compound (I)＞ (I-1): Sumidur N-3300, manufactured by Sumika Bayer Urethane, hexamethylene diisocyanate (HDI)/isocyanurate, solid Ingredients 100% by mass, (I-2): Coronate HL, manufactured by Tosoh Corporation, hexamethylene diisocyanate (HDI)/trimethylolpropane (TMP) adduct, solid content 75% by mass, (I-3): Desmodur Z4470BA, manufactured by Sumika Bayer Urethane, isophorone diisocyanate (IPDI)/isocyanurate, solid content 70% by mass.

[Production of solution containing urethane prepolymer or solution containing polyol] (Manufacturing Example 1) (Two-stage polymerization method) A four-necked flask equipped with a stirrer, a reflux cooling tube, a nitrogen introduction tube, a thermometer, and a dropping funnel was charged with 100 parts by mass of polyol (HA-1) and 40 parts by mass of polyisocyanate (N-1) as a diluent 10 parts by mass of organic solvent (B-1), 100 parts by mass of plasticizer (P-1), and 0.01 parts by mass of dioctyltin dilaurate as a catalyst, and mixed. The content liquid was gradually heated to 80°C and reacted for 2 hours to obtain an isocyanate group-terminated urethane prepolymer (first-stage reaction). Then, the content liquid is cooled to 60 degreeC, 20 mass parts of active hydrogen group-containing compounds (HB-2) are added, and it mixes and makes it react (reaction in the second stage). In the entire reaction of the first stage and the second stage, the molar number of isocyanate groups (NCO) of the polyisocyanate (N) used in the reaction is relative to all the active hydrogen group-containing compounds used in the reaction ( HX) ((HA-1) and (HB-2) in this example) the ratio (NCO/H) of the total moles of active hydrogen groups (H) possessed is 0.62. After confirming the disappearance of the remaining isocyanate groups by infrared spectroscopy analysis (infrared radiation (IR) analysis), the content liquid is cooled to complete the reaction, and 1 part by mass of antioxidant (D-1) and β-diketone are added 3 parts by mass of compound (X-1) were mixed. As described above, a colorless and transparent solution of the hydroxyl terminal urethane prepolymer (UPH-1) was obtained. The main manufacturing conditions and evaluation results are shown in Table 1-1 and Table 2-1. Table 1-1 to Table 1-7 show the raw material composition of the urethane prepolymer alone or the polyol mixture alone, NCO/H, and the Mn and Mw of the urethane prepolymer. Table 2-1 to Table 2-2 show the composition of the urethane prepolymer-containing solution or the polyol-containing solution, the solid content concentration, and the 25°C after being allowed to stand at 25°C for 1 hour shortly after preparation Under the viscosity. The unit of the blending amount in the table is "parts by mass" (the same in other tables).

(Manufacturing example 2 to manufacturing example 40, manufacturing example 42 to manufacturing example 45) (two-stage polymerization method) Except for changing the types and blending ratios of the raw materials used, in the same manner as in Production Example 1, the hydroxyl-containing terminal urethane prepolymers (UPH-2) to (UPH-45) were obtained by the two-stage polymerization method. Solution. A four-necked flask equipped with a stirrer, a reflux cooling tube, a nitrogen introduction tube, a thermometer, and a dropping funnel is charged with 100 parts by mass of one or more polyols (HA) or one or more polyols (HL), and one or more polyols. The isocyanate (N), the organic solvent (B) and/or the plasticizer (P) as a diluent, and 0.01 parts by mass of dioctyltin dilaurate as a catalyst are mixed. The content liquid was gradually heated to 80°C and reacted for 2 hours to obtain an isocyanate group-terminated urethane prepolymer (first-stage reaction). Then, the content liquid is cooled to 60° C., and one or more active hydrogen group-containing compounds (HB) are added, mixed and reacted (second-stage reaction). After confirming the disappearance of the remaining isocyanate groups by infrared spectroscopy analysis (IR analysis), the content liquid is cooled to complete the reaction, and then antioxidant (D-1) and β-diketone compound (X-1) are added, and then optionally Add AS agent (F-1) and mix. As described above, a colorless and transparent hydroxyl-containing terminal urethane prepolymer (UPH-2) to (UPH-32), (UPH-34), (UPH-37) solutions were obtained. The main manufacturing conditions and evaluation results are shown in Table 1-1 to Table 1-6, and Table 2-1 to Table 2-2.

(Manufacturing Example 41) (Two-stage polymerization method) Except for changing the type and blending ratio of the raw materials used, in the same manner as in Production Example 1, a solution of a hydroxyl group-containing terminal urethane prepolymer (UPH-33) was obtained by a two-stage polymerization method. A four-necked flask equipped with a stirrer, a reflux cooling tube, a nitrogen introduction tube, a thermometer, and a dropping funnel was charged with 100 parts by mass of polyol (HB-6) and 80 parts by mass of polyisocyanate (N-1) as a diluent 10 parts by mass of organic solvent (B-1), 100 parts by mass of plasticizer (P-1), and 0.01 parts by mass of dioctyltin dilaurate as a catalyst, and mixed. The content liquid was gradually heated to 80°C and reacted for 2 hours to obtain an isocyanate group-terminated urethane prepolymer (first-stage reaction). Then, the content liquid was cooled to 60° C., and the active hydrogen group-containing compound (HB-2) was added, mixed and reacted (second-stage reaction). After confirming the disappearance of the remaining isocyanate groups by infrared spectroscopy analysis (IR analysis), the content liquid is cooled to complete the reaction, and then antioxidant (D-1) and β-diketone compound (X-1) are added and mixed . As described above, a colorless and transparent solution of hydroxyl terminal urethane prepolymer (UPH-41) was obtained. The main manufacturing conditions and evaluation results are shown in Table 1-6 and Table 2-2.

(Manufacturing Example 46) (One-stage polymerization method) A four-necked flask equipped with a stirrer, a reflux cooling tube, a nitrogen introduction tube, a thermometer, and a dropping funnel is charged with 100 parts by mass of polyol (HA-6) and 8 parts by mass of active hydrogen group-containing compound (HB-2) , 10 parts by mass of organic solvent (B-1) as a diluent, 100 parts by mass of plasticizer (P-1), and 0.01 parts by mass of dioctyltin dilaurate as a catalyst, and mixed, The temperature of the liquid was slowly raised to 80°C. Then, 13 parts by mass of polyisocyanate (N-1) were added and the reaction was performed for 2 hours. After confirming the disappearance of the remaining isocyanate groups by infrared spectroscopy analysis (IR analysis), the content liquid is cooled to complete the reaction, and 1 part by mass of antioxidant (D-1) and β-diketone compound (X-1) 3 are added Parts by mass, and mix. As described above, a colorless and transparent solution of hydroxyl terminal urethane prepolymer (UPH-38) was obtained. The main manufacturing conditions and evaluation results are shown in Table 1-6 and Table 2-2.

(Manufacturing Example 47, Manufacturing Example 48) (One-stage polymerization method) A four-necked flask equipped with a stirrer, a reflux cooling tube, a nitrogen introduction tube, a thermometer, and a dropping funnel was charged with 30 parts by mass of polyol (HA-1), 70 parts by mass of polyol (HA-7), and polyisocyanate ( N-2) 5 parts by mass, 90 parts by mass or 30 parts by mass of organic solvent (B-1) as a diluent, 40 parts by mass of plasticizer (P-1), and dioctyl dilaurate as a catalyst 0.01 parts by mass of tin, and mixed. The content liquid was gradually raised to 80°C and reacted for 2 hours. After confirming the disappearance of the remaining isocyanate groups by infrared spectroscopy analysis (IR analysis), the content liquid is cooled to complete the reaction, and 1 part by mass of antioxidant (D-1) and β-diketone compound (X-1) 3 are added Parts by mass, and mix. As described above, a colorless and transparent solution of the hydroxyl-containing terminal urethane prepolymer (UPH-39) for comparison was obtained. The main manufacturing conditions and evaluation results are shown in Table 1-7 and Table 2-2.

(Manufacturing Example 49) (One-stage polymerization method) A four-necked flask equipped with a stirrer, a reflux cooling tube, a nitrogen introduction tube, a thermometer, and a dropping funnel was charged with 100 parts by mass of polyol (HA-6) and 5 parts by mass of active hydrogen group-containing compound (HB-2) , 40 parts by mass of polyisocyanate (N-1), 10 parts by mass of organic solvent (B-1) as a diluent, 100 parts by mass of plasticizer (P-1), and dioctyl dilaurate as a catalyst 0.01 parts by mass of tin, and mixed. The content liquid was gradually raised to 80°C and reacted for 2 hours. After cooling the content liquid to complete the reaction, 1 part by mass of antioxidant (D-1) and 3 parts by mass of β-diketone compound (X-1) are added and mixed. As described above, a colorless and transparent solution of the isocyanate group-containing terminal urethane prepolymer (UPN-1) for comparison was obtained. The main manufacturing conditions and evaluation results are shown in Table 1-7 and Table 2-2.

(Manufacturing Example 50) By mixing 100 parts by mass of polyol (HA-6), 5 parts by mass of active hydrogen group-containing compound (HB-2), 10 parts by mass of organic solvent (B-1) as a diluent, and plasticizer (P- 1) 100 parts by mass, 0.01 parts by mass of dioctyltin dilaurate as a catalyst, 1 part by mass of antioxidant (D-1), and 3 parts by mass of β-diketone compound (X-1) to obtain colorless and transparent A solution containing polyol (PO-1) for comparison. The main manufacturing conditions and evaluation results are shown in Table 1-7 and Table 2-2.

[Manufacturing of Urethane Adhesives and Adhesive Sheets] (Example 1 to Example 54, Comparative Example 1 to Comparative Example 4) Prepare the urethane prepolymer-containing solution or the polyol-containing solution, the polyfunctional isocyanate compound (I), and any organic solvent (B) obtained in any of the above production examples, and use a dispersing machine Stirring is performed to obtain a urethane-based adhesive. With respect to the obtained adhesive, evaluations of the solid content concentration, the viscosity after being allowed to stand at 25°C for 3 hours shortly after preparation, and the pot life were performed. A 50 μm thick polyethylene terephthalate (PET) film (Lumirror T-60, manufactured by Toray) was prepared as a substrate sheet. Using a chipped wheel coater (registered trademark), the urethane-based adhesive, which was allowed to stand at 25°C for 3 hours shortly after preparation, was applied to the substrate sheet so that the thickness after drying became 12 μm Of one side. Then, the formed coating layer was dried at 100°C for two minutes to form an adhesive layer. A release sheet (Super Stik SP-PET38, manufactured by Lintec) with a thickness of 38 μm was attached to the adhesive layer to obtain an adhesive sheet. After curing for a predetermined period of time under the conditions of 23°C-50%RH, evaluation of initial hardenability, wettability, and re-peelability was performed. In addition, Comparative Example 4 is an example in which the adhesive is produced by a single pass method. The formulation composition of the adhesive and the evaluation results of the adhesive and the adhesive sheet are shown in Table 3-1 to Table 3-2, Table 4-1 to Table 4-2.

[Evaluation results] In Production Example 1 to Production Example 46, a solution containing a hydroxyl terminal urethane prepolymer can be prepared, and the solution of the hydroxyl terminal urethane prepolymer contains as one or more active hydrogen group-containing The hydroxyl-terminated urethane prepolymer (UPH) of the reaction product of the compound (HX) and one or more polyisocyanates (N), and the solid content concentration is 80% by mass or more, and it is allowed to stand at 25°C shortly after preparation. The viscosity at 25°C after 1 hour is 8000 mPa·s or less. In these production examples, it is possible to synthesize a solution of a hydroxyl terminal urethane prepolymer with a reduced usage amount of an organic solvent, a relatively high solid content concentration, and a relatively low viscosity.

In Example 1 to Example 54, an adhesive can be prepared. The adhesive includes the hydroxyl-terminated terminal urethane prepolymer solution obtained in any of the manufacturing examples of Manufacturing Example 1 to Manufacturing Example 46 and the Functional isocyanate compound (I) with a solid content concentration of 70% by mass or more or 80% by mass or more, and the viscosity at 25°C after being left at 25°C for 3 hours shortly after preparation is 9000 mPa·s or less or 5000 mPa· s or less. In these Examples, an adhesive that was allowed to stand at 25° C. for 3 hours shortly after preparation was used to produce an adhesive sheet. In any of the examples, the coating properties of the adhesive were good. In Example 1 to Example 54, an adhesive with a reduced usage of organic solvents, a relatively high solid content concentration, and a relatively low viscosity at the time of application can be produced to have good application adaptability. In these embodiments, an adhesive with a good pot life can be produced, and an adhesive sheet with good initial hardening, wettability, and re-peelability can be produced.

The solution of the hydroxyl terminal urethane prepolymer obtained in Production Example 47 had a low solid content concentration, and the adhesive of Comparative Example 1 using it had a low solid content concentration, and the VOC reduction effect was poor. The solution of the hydroxyl-terminated urethane prepolymer obtained in Production Example 48 had a high viscosity, and the adhesive of Comparative Example 2 using it had high viscosity, poor pot life, and poor applicability. The pot life of the adhesive of Comparative Example 3 using the solution of the isocyanate group-containing terminal urethane prepolymer obtained in Production Example 49 was poor, and the initial hardenability of the adhesive sheet using the same was poor. As with the polyhydric alcohol-containing solution obtained in Production Example 50, the polyhydric alcohol-containing solution was used in Comparative Example 4 to produce an adhesive by a single-shot method. The initial hardenability of the adhesive sheet using the adhesive is poor.

[Table 1-1] Manufacturing example 1 Manufacturing example 2 Manufacturing example 3 Manufacturing example 4 Manufacturing example 5 Manufacturing example 6-manufacturing example 14 Manufacturing example 15 Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization species Number of functional groups Mn UPH-1 UPH-2 UPH-3 UPH-4 UPH-5 UPH-6 UPH-7 HA-1 Polyester polyol P-1010 2 1000 100.0 HA-2 F-3010 3 3000 100.0 HA-3 Polyethylene glycol PEG1000 2 1000 100.0 HA-4 Polyolefin polyol poly bd 2 2400 100.0 HA-5 Polypropylene glycol PP2000 2 2000 100.0 HA-6 EXCE5030 3 5100 100.0 HA-7 EXCE851 3 6700 100.0 HA-8 Polypropylene glycol PREM S4013F 2 12000 HA-9 PREM S3011 3 10000 HB-1 Ethylene glycol 2 62.1 HB-2 1,5-pentanediol 2 104.2 20.0 12.0 15.0 10.0 8.0 8.0 5.0 HB-3 2-ethyl-1,3-hexanediol 2 146.2 HB-4 PPG200 2 200 HB-5 PEG300 2 300 HB-6 PEG600 2 600 HB-7 glycerin 3 92 HB-8 Trimethylolpropane TMP 3 134 HB-9 1-methylamino-2,3-propanediol MAPD 3 105 N-1 Isophorone diisocyanate IPDI 2 222.2 40.0 22.0 40.0 20.0 22.0 13.0 10.0 N-2 Hexamethylene diisocyanate HDI 2 168.2 N-3 Toluene diisocyanate TDI 2 174.2 NCO/H 0.62 0.60 0.74 0.65 0.78 0.55 0.64 Mn 19000 23800 22800 16200 14,300 19500 23300 Mw 32000 40000 38400 27200 24000 32800 39200

[Table 1-2] Manufacturing example 16 Manufacturing example 17 Manufacturing example 18 Manufacturing example 19 Manufacturing example 20 Manufacturing example 21 Manufacturing example 22 Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization species Number of functional groups Mn UPH-8 UPH-9 UPH-10 UPH-11 UPH-12 UPH-13 UPH-14 HA-1 Polyester polyol P-1010 2 1000 HA-2 F-3010 3 3000 HA-3 Polyethylene glycol PEG1000 2 1000 HA-4 Polyolefin polyol poly bd 2 2400 HA-5 Polypropylene glycol PP2000 2 2000 100.0 100.0 100.0 100.0 HA-6 EXCE5030 3 5100 100.0 100.0 100.0 HA-7 EXCE851 3 6700 HA-8 Polypropylene glycol PREM S4013F 2 12000 HA-9 PREM S3011 3 10000 HB-1 Ethylene glycol 2 62.1 5.0 5.0 HB-2 1,5-pentanediol 2 104.2 7.0 7.0 HB-3 2-ethyl-1,3-hexanediol 2 146.2 HB-4 PPG200 2 200 3.0 3.0 HB-5 PEG300 2 300 22.0 22.0 HB-6 PEG600 2 600 HB-7 glycerin 3 92 HB-8 Trimethylolpropane TMP 3 134 14.0 HB-9 1-methylamino-2,3-propanediol MAPD 3 105 N-1 Isophorone diisocyanate IPDI 2 222.2 22.0 22.0 22.0 22.0 13.0 13.0 13.0 N-2 Hexamethylene diisocyanate HDI 2 168.2 N-3 Toluene diisocyanate TDI 2 174.2 NCO/H 0.76 0.75 0.80 0.48 0.53 0.52 0.57 Mn 11400 12000 16,500 19600 19000 17100 22800 Mw 19200 20300 27700 33100 32000 28800 38400

[Table 1-3] Manufacturing example 23 Manufacturing example 24 Manufacturing example 25 Manufacturing example 26 Manufacturing example 27 Manufacturing example 28 Manufacturing example 29 Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization species Number of functional groups Mn UPH-15 UPH-16 UPH-17 UPH-18 UPH-19 UPH-20 UPH-21 HA-1 Polyester polyol P-1010 2 1000 50.0 HA-2 F-3010 3 3000 50.0 HA-3 Polyethylene glycol PEG1000 2 1000 HA-4 Polyolefin polyol poly bd 2 2400 50.0 HA-5 Polypropylene glycol PP2000 2 2000 50.0 HA-6 EXCE5030 3 5100 100.0 50.0 100.0 100.0 100.0 HA-7 EXCE851 3 6700 50.0 HA-8 Polypropylene glycol PREM S4013F 2 12000 HA-9 PREM S3011 3 10000 HB-1 Ethylene glycol 2 62.1 3.0 3.0 3.0 HB-2 1,5-pentanediol 2 104.2 15.0 7.0 6.0 HB-3 2-ethyl-1,3-hexanediol 2 146.2 2.0 HB-4 PPG200 2 200 HB-5 PEG300 2 300 5.0 HB-6 PEG600 2 600 HB-7 glycerin 3 92 HB-8 Trimethylolpropane TMP 3 134 15.0 3.0 HB-9 1-methylamino-2,3-propanediol MAPD 3 105 N-1 Isophorone diisocyanate IPDI 2 222.2 13.0 35.0 18.0 15.0 13.0 13.0 13.0 N-2 Hexamethylene diisocyanate HDI 2 168.2 N-3 Toluene diisocyanate TDI 2 174.2 NCO/H 0.30 0.72 0.76 0.75 0.62 0.64 0.53 Mn 33300 11100 19000 17,600 17,600 15200 22300 Mw 56000 18700 32000 29600 29600 25600 37600

[Table 1-4] Manufacturing example 30 Manufacturing example 31 Manufacturing example 32 Manufacturing example 33 Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization species Number of functional groups Mn UPH-22 UPH-23 UPH-24 UPH-25 HA-1 Polyester polyol P-1010 2 1000 HA-2 F-3010 3 3000 HA-3 Polyethylene glycol PEG1000 2 1000 HA-4 Polyolefin polyol poly bd 2 2400 HA-5 Polypropylene glycol PP2000 2 2000 HA-6 EXCE5030 3 5100 100.0 100.0 100.0 100.0 HA-7 EXCE851 3 6700 HA-8 Polypropylene glycol PREM S4013F 2 12000 HA-9 PREM S3011 3 10000 HB-1 Ethylene glycol 2 62.1 HB-2 1,5-pentanediol 2 104.2 25.0 5.4 8.0 8.0 HB-3 2-ethyl-1,3-hexanediol 2 146.2 HB-4 PPG200 2 200 HB-5 PEG300 2 300 HB-6 PEG600 2 600 HB-7 glycerin 3 92 HB-8 Trimethylolpropane TMP 3 134 HB-9 1-methylamino-2,3-propanediol MAPD 3 105 N-1 Isophorone diisocyanate IPDI 2 222.2 15.0 15.0 8.0 8.0 N-2 Hexamethylene diisocyanate HDI 2 168.2 4.0 N-3 Toluene diisocyanate TDI 2 174.2 4.0 NCO/H 0.25 0.83 0.56 0.56 Mn 8800 55,000 15,700 15200 Mw 13,500 75000 26400 25600

[Table 1-5] Manufacturing example 34 Manufacturing example 35 Manufacturing example 36 Manufacturing example 37 Manufacturing example 38 Manufacturing example 39 Manufacturing example 40 Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization species Number of functional groups Mn UPH-26 UPH-27 UPH-28 UPH-29 UPH-30 UPH-31 UPH-32 HA-1 Polyester polyol P-1010 2 1000 HA-2 F-3010 3 3000 HA-3 Polyethylene glycol PEG1000 2 1000 HA-4 Polyolefin polyol poly bd 2 2400 HA-5 Polypropylene glycol PPG2000 2 2000 HA-6 EXCE5030 3 5100 100.0 100.0 100.0 100.0 100.0 HA-7 EXCE851 3 6700 HA-8 Polypropylene glycol PREM S4013F 2 12000 100.0 HA-9 PREM S3011 3 10000 100.0 HB-1 Ethylene glycol 2 62.1 HB-2 1,5-pentanediol 2 104.2 2.0 4.0 HB-3 2-ethyl-1,3-hexanediol 2 146.2 10.0 HB-4 PPG200 2 200 15.0 HB-5 PEG300 2 300 HB-6 PEG600 2 600 30.0 HB-7 glycerin 3 92 10.0 HB-8 Trimethylolpropane TMP 3 134 HB-9 1-methylamino-2,3-propanediol MAPD 3 105 5.0 N-1 Isophorone diisocyanate IPDI 2 222.2 13.0 13.0 13.0 13.0 4.0 7.0 13.0 N-2 Hexamethylene diisocyanate HDI 2 168.2 N-3 Toluene diisocyanate TDI 2 174.2 NCO/H 0.60 0.56 0.30 0.58 0.65 0.59 0.74 Mn 14,700 18500 28500 20900 47000 29900 35600 Mw 24800 31200 48000 35200 65,000 50400 60000

[Table 1-6] Manufacturing example 41 Manufacturing example 42 Manufacturing example 43 Manufacturing example 44 Manufacturing example 45 Manufacturing example 46 Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization Two-stage polymerization One-stage polymerization species Number of functional groups Mn UPH-33 UPH-34 UPH-35 UPH-36 UPH-37 UPH-38 HA-1 Polyester polyol P-1010 2 1000 HA-2 F-3010 3 3000 HA-3 Polyethylene glycol PEG1000 2 1000 HA-4 Polyolefin polyol poly bd 2 2400 HA-5 Polypropylene glycol PPG2000 2 2000 100.0 HA-6 EXCE5030 3 5100 100.0 100.0 100.0 100.0 HA-7 EXCE851 3 6700 HA-8 Polypropylene glycol PREM S4013F 2 12000 HA-9 PREM S3011 3 10000 HB-1 Ethylene glycol 2 62.1 HB-2 1,5-pentanediol 2 104.2 35.0 7.0 7.0 30.0 5.5 8.0 HB-3 2-ethyl-1,3-hexanediol 2 146.2 HB-4 PPG200 2 200 HB-5 PEG300 2 300 HB-6 PEG600 2 600 100.0 HB-7 glycerin 3 92 HB-8 Trimethylolpropane TMP 3 134 HB-9 1-methylamino-2,3-propanediol MAPD 3 105 N-1 Isophorone diisocyanate IPDI 2 222.2 80.0 13.0 20.0 13.0 N-2 Hexamethylene diisocyanate HDI 2 168.2 10.0 N-3 Toluene diisocyanate TDI 2 174.2 10.0 NCO/H 0.72 0.62 0.59 0.18 0.88 0.55 Mn 9800 34700 33700 7800 75000 14,700 Mw 16,500 58400 56800 9300 95000 24800

[Table 1-7] Manufacturing Example 47-Manufacturing Example 48 Manufacturing example 49 Manufacturing example 50 One-stage polymerization One-stage polymerization mixing species Number of functional groups Mn UPH-39 UPN-1 PO-1 HA-1 Polyester polyol P-1010 2 1000 30.0 HA-2 F-3010 3 3000 HA-3 Polyethylene glycol PEG1000 2 1000 HA-4 Polyolefin polyol poly bd 2 2400 HA-5 Polypropylene glycol PP2000 2 2000 HA-6 EXCE5030 3 5100 100.0 100.0 HA-7 EXCE851 3 6700 70.0 HA-8 Polypropylene glycol PREM S4013F 2 12000 HA-9 PREM S3011 3 10000 HB-1 Ethylene glycol 2 62.1 HB-2 1,5-pentanediol 2 104.2 5.0 5.0 HB-3 2-ethyl-1,3-hexanediol 2 146.2 HB-4 PPG200 2 200 HB-5 PEG300 2 300 HB-6 PEG600 2 600 HB-7 glycerin 3 92 HB-8 Trimethylolpropane TMP 3 134 HB-9 1-methylamino-2,3-propanediol MAPD 3 105 N-1 Isophorone diisocyanate IPDI 2 222.2 40.0 N-2 Hexamethylene diisocyanate HDI 2 168.2 5.0 N-3 Toluene diisocyanate TDI 2 174.2 NCO/H 0.65 2.33 - Mn - Mw 150000 9500 -

[table 2-1] Solution containing urethane prepolymer or solution containing polyol Urethane prepolymer Polyol mixture Thinner Antioxidant (D) β-diketone compound (X) AS agent (F) Measurement item Organic solvent (B) Plasticizer (P) Viscosity at 25°C (after 1 hour shortly after preparation) Solid content concentration species Share species Share B-1 P-1 P-2 P-3 D-1 X-1 F-1 mPa·s Manufacturing example 1 UPH-1 100 10 100 1 3 6000 93% Manufacturing example 2 UPH-2 100 10 100 1 3 5000 93% Manufacturing example 3 UPH-3 100 10 100 1 3 7200 93% Manufacturing example 4 UPH-4 100 10 100 1 3 6800 93% Manufacturing example 5 UPH-5 100 10 100 1 3 6000 93% Manufacturing example 6 UPH-6 100 20 1 3 4100 81% Manufacturing example 7 100 10 20 1 3 6200 90% Manufacturing example 8 100 50 1 3 5500 98% Manufacturing example 9 100 100 1 3 3300 98% Manufacturing example 10 100 150 1 3 1500 98% Manufacturing example 11 100 200 1 3 800 99% Manufacturing example 12 100 10 100 1 3 1800 93% Manufacturing example 13 100 10 100 1 3 1700 93% Manufacturing example 14 100 10 100 1 3 1 1700 93% Manufacturing example 15 UPH-7 100 10 100 1 3 4900 93% Manufacturing example 16 UPH-8 100 10 100 1 3 3600 93% Manufacturing example 17 UPH-9 100 10 100 1 3 3800 93% Manufacturing example 18 UPH-10 100 10 100 1 3 5200 93% Manufacturing example 19 UPH-11 100 10 100 1 3 6200 93% Manufacturing example 20 UPH-12 100 10 100 1 3 4000 93% Manufacturing example 21 UPH-13 100 10 100 1 3 3600 93% Manufacturing example 22 UPH-14 100 10 100 1 3 4800 93% Manufacturing example 23 UPH-15 100 10 100 1 3 7000 93% Manufacturing example 24 UPH-16 100 10 100 1 3 3500 93% Manufacturing example 25 UPH-17 100 10 100 1 3 4000 93% Manufacturing example 26 UPH-18 100 10 100 1 3 3700 93% Manufacturing example 27 UPH-19 100 10 100 1 3 3700 93% Manufacturing example 28 UPH-20 100 10 100 1 3 3200 93% Manufacturing example 29 UPH-21 100 10 100 1 3 4700 93% Manufacturing example 30 UPH-22 100 10 100 1 3 900 93%

[Table 2-2] Solution containing urethane prepolymer or solution containing polyol Urethane prepolymer Polyol mixture Thinner Antioxidant (D) β-diketone compound (X) AS agent (F) Measurement item Organic solvent (B) Plasticizer (P) Viscosity at 25°C (after 1 hour shortly after preparation) Solid content concentration species Share species Share B-1 P-1 P-2 P-3 D-1 X-1 F-1 mPa·s Manufacturing example 31 UPH-23 100 10 100 1 3 7500 93% Manufacturing example 32 UPH-24 100 10 100 1 3 3300 93% Manufacturing example 33 UPH-25 100 10 100 1 3 3200 93% Manufacturing example 34 UPH-26 100 10 100 1 3 3100 93% Manufacturing example 35 UPH-27 100 10 100 1 3 3900 93% Manufacturing example 36 UPH-28 100 10 100 1 3 6000 93% Manufacturing example 37 UPH-29 100 10 100 1 3 4400 93% Manufacturing example 38 UPH-30 100 10 100 1 3 6800 93% Manufacturing example 39 UPH-31 100 10 100 1 3 6300 93% Manufacturing example 40 UPH-32 100 10 100 1 3 7500 93% Manufacturing example 41 UPH-33 100 10 100 1 3 3100 93% Manufacturing example 42 UPH-34 100 10 100 1 3 7300 93% Manufacturing example 43 UPH-35 100 10 100 1 3 7100 93% Manufacturing example 44 UPH-36 100 10 100 1 3 400 93% Manufacturing example 45 UPH-37 100 10 100 1 3 7600 93% Manufacturing example 46 UPH-38 100 10 100 1 3 3100 93% Manufacturing example 47 UPH-39 100 90 40 1 3 2800 60% Manufacturing example 48 100 30 40 1 3 12000 81% Manufacturing example 49 UPN-1 100 10 100 1 3 4200 93% Manufacturing example 50 PO-1 100 10 100 1 3 1200 93%

[Table 3-1] Adhesive Solution containing urethane prepolymer Solution containing polyol Multifunctional isocyanate compound (I) Organic solvent (B) Measurement item Viscosity at 25°C (after 3 hours shortly after preparation) Solid content concentration Manufacturing example Share Manufacturing example Share I-1 I-2 I-3 B-1 mPa·s Example 1 1 100 10 6300 94% Example 2 2 100 10 4900 94% Example 3 3 100 10 7600 94% Example 4 4 100 10 7100 94% Example 5 5 100 10 6400 94% Example 6 6 100 10 5200 83% Example 7 7 100 10 7200 91% Example 8 8 100 10 5800 98% Example 9 9 100 1 3200 98% Example 10 100 5 3100 98% Example 11 100 10 3000 98% Example 12 100 10 40 400 72% Example 13 100 20 3100 98% Example 14 100 30 2900 98% Example 15 100 10 3100 91% Example 16 100 10 3100 91% Example 17 100 10 20 1400 83% Example 18 10 100 10 1300 98% Example 19 11 100 10 800 99% Example 20 12 100 10 1700 94% Example 21 13 100 10 1600 94% Example 22 14 100 10 1600 94% Example 23 15 100 10 4700 94% Example 24 16 100 10 3500 94% Example 25 17 100 10 3700 94% Example 26 18 100 10 5000 94% Example 27 19 100 10 7200 94% Example 28 20 100 10 3900 94% Example 29 twenty one 100 10 3500 94% Example 30 twenty two 100 10 4600 94%

[Table 3-2] Adhesive Solution containing urethane prepolymer Solution containing polyol Multifunctional isocyanate compound (I) Organic solvent (B) Measurement item Viscosity at 25°C (after 3 hours shortly after preparation) Solid content concentration Manufacturing example Share Manufacturing example Share I-1 I-2 I-3 B-1 mPa·s Example 31 twenty three 100 10 7900 94% Example 32 twenty four 100 10 3400 94% Example 33 25 100 10 3900 94% Example 34 26 100 10 3600 94% Example 35 27 100 10 3600 94% Example 36 28 100 10 3100 94% Example 37 29 100 10 4600 94% Example 38 30 100 10 900 94% Example 39 31 100 10 7900 94% Example 40 32 100 10 3200 94% Example 41 33 100 10 3100 94% Example 42 34 100 10 3000 94% Example 43 35 100 10 3800 94% Example 44 36 100 10 6400 94% Example 45 37 100 10 5400 94% Example 46 38 100 10 7800 94% Example 47 39 100 10 7500 94% Example 48 40 100 10 7700 94% Example 49 41 100 10 3000 94% Example 50 42 100 10 7900 94% Example 51 43 100 10 7800 94% Example 52 44 100 10 400 94% Example 53 45 100 10 8500 94% Example 54 46 100 10 3000 94% Comparative example 1 47 100 10 2700 63% Comparative example 2 48 100 10 15000 82% Comparative example 3 49 100 10 7000 94% Comparative example 4 50 100 10 1200 94%

[Table 4-1] Adhesive Adhesive sheet VOC reduction effect Applicable period Initial hardening Wettability Peelability Example 1 ◎ ○ ○ △ △ Example 2 ◎ ◎ ○ △ ○ Example 3 ◎ ○ ○ △ △ Example 4 ◎ ○ ○ △ △ Example 5 ◎ ○ ○ ○ △ Example 6 ○ △ ○ ○ ○ Example 7 ◎ △ ○ ○ ○ Example 8 ◎ ○ ○ ○ ○ Example 9 ◎ ◎ △ ○ △ Example 10 ◎ ◎ ○ ○ ○ Example 11 ◎ ◎ ○ ○ ○ Example 12 △ ◎ ○ ○ ○ Example 13 ◎ ◎ ○ ○ ○ Example 14 ◎ ○ ○ ○ ○ Example 15 ◎ ◎ ○ ○ ○ Example 16 ◎ ◎ ○ ○ ○ Example 17 ○ ◎ ○ ○ ○ Example 18 ◎ ◎ ○ ○ ○ Example 19 ◎ ◎ △ ○ ○ Example 20 ◎ ◎ ○ ○ ○ Example 21 ◎ ◎ ○ ○ ○ Example 22 ◎ ◎ ○ ○ ○ Example 23 ◎ ◎ ○ ○ ○ Example 24 ◎ ◎ ○ ○ △ Example 25 ◎ ◎ ○ ○ △ Example 26 ◎ ◎ ○ ○ △ Example 27 ◎ △ ○ ○ △ Example 28 ◎ ◎ ○ ○ ○ Example 29 ◎ ◎ ○ ○ ○ Example 30 ◎ ◎ ○ ○ ○

[Table 4-2] Adhesive Adhesive sheet VOC reduction effect Applicable period Initial hardening Wettability Peelability Example 31 ◎ △ ○ ○ ○ Example 32 ◎ ◎ ○ ○ △ Example 33 ◎ ◎ ○ ○ ○ Example 34 ◎ ◎ ○ ○ ○ Example 35 ◎ ◎ ○ ○ ○ Example 36 ◎ ◎ ○ ○ ○ Example 37 ◎ ◎ ○ ○ ○ Example 38 ◎ ◎ ○ ○ ○ Example 39 ◎ ○ ○ ○ ○ Example 40 ◎ ◎ ○ ○ ○ Example 41 ◎ ◎ ○ ○ ○ Example 42 ◎ ◎ △ ○ ○ Example 43 ◎ ◎ △ ○ ○ Example 44 ◎ ○ △ ○ ○ Example 45 ◎ △ ○ ○ ○ Example 46 ◎ △ ○ ○ △ Example 47 ◎ △ ○ ○ ○ Example 48 ◎ ○ △ ○ ○ Example 49 ◎ ◎ △ ○ △ Example 50 ◎ △ ○ ○ ○ Example 51 ◎ △ ○ ○ ○ Example 52 ◎ ◎ △ ○ ○ Example 53 ◎ △ ○ ○ ○ Example 54 ◎ ◎ △ ○ ○ Comparative example 1 X ◎ △ ○ ○ Comparative example 2 ○ X △ ○ ○ Comparative example 3 ◎ X X ○ X Comparative example 4 ◎ ◎ X ○ ○

The present invention is not limited to the above-mentioned embodiments and examples, and design changes can be appropriately made without departing from the gist of the present invention.

This application claims priority based on the Japanese patent application Japanese Patent Application No. 2019-091953 filed on May 15, 2019, and incorporates all the contents disclosed in this specification.

10, 20: Adhesive sheet 11, 21: substrate sheet 12, 22A, 22B: Adhesive layer 13, 23A, 23B: release sheet

Fig. 1 is a schematic cross-sectional view of an adhesive sheet according to a first embodiment of the present invention. Fig. 2 is a schematic cross-sectional view of an adhesive sheet according to a second embodiment of the present invention.

10: Adhesive sheet

11: Substrate sheet

12: Adhesive layer

13: Peel off sheet

Claims (16)

A solution containing a hydroxyl terminal urethane prepolymer, which is used in an adhesive, the solution containing a hydroxyl terminal urethane prepolymer comprises a hydroxyl terminal urethane prepolymer (UPH) The hydroxyl-terminated urethane prepolymer (UPH) is a combination of more than one active hydrogen group-containing compound (HX) with multiple active hydrogen groups in one molecule, and more than one polyisocyanate (N) Reaction product, and The solid content concentration is 80% by mass or more, and the viscosity at 25° C. after being allowed to stand at 25° C. for 1 hour shortly after preparation is 8000 mPa·s or less. The solution of the hydroxyl terminal urethane prepolymer according to claim 1, wherein the one or more active hydrogen group-containing compounds (HX) comprise one or more polyols having a number average molecular weight of 1000 or more ( HA) and one or more active hydrogen group-containing compounds (HB) having multiple active hydrogen groups in a molecule with a number average molecular weight of less than 1,000. The solution of the hydroxyl terminal urethane prepolymer according to claim 1 or claim 2, wherein the one or more polyols (HA) comprise polyether polyols with more than trifunctionality. The solution of the hydroxyl-terminated terminal urethane prepolymer according to claim 1 or claim 2, wherein the number of moles of isocyanate groups (NCO) possessed by the one or more polyisocyanates (N) is relative to The ratio (NCO/H) of the total number of moles of the active hydrogen groups (H) possessed by the one or more active hydrogen group-containing compounds (HX) is 0.20 to 0.84. The solution of the hydroxyl-terminated urethane prepolymer according to claim 1 or claim 2, wherein the hydroxyl-terminated urethane prepolymer (UPH) is an isocyanate group-terminated urethane The reaction product of a prepolymer (UPN) and an active hydrogen group-containing compound (HB), the isocyanate group terminal urethane prepolymer (UPN) is a reaction of a polyol (HA) and a polyisocyanate (N) product. The solution of the hydroxyl terminal urethane prepolymer according to claim 1 or claim 2, wherein the one or more polyisocyanates (N) comprise isophorone diisocyanate. The solution of the hydroxyl-containing terminal urethane prepolymer according to claim 1 or 2, wherein the active hydrogen group-containing compound (HB) contains a primary hydroxyl group. An adhesive comprising the hydroxyl-containing terminal urethane prepolymer solution according to any one of claims 1 to 7 and a polyfunctional isocyanate compound (I). The adhesive according to claim 8, wherein the solid content concentration is 80% by mass or more, and the viscosity at 25°C after being allowed to stand at 25°C for 3 hours shortly after preparation is 5000 mPa·s or less. The adhesive described in claim 8 or claim 9 further contains a plasticizer. The adhesive according to claim 8 or claim 9, further comprising a β-diketone compound. The adhesive described in claim 8 or claim 9 further contains an antistatic agent. The adhesive according to claim 8 or claim 9 further includes one or more anti-deteriorating agents selected from the group consisting of antioxidants, hydrolysis resistant agents, ultraviolet absorbers, and light stabilizers. An adhesive sheet comprising a substrate sheet and an adhesive layer containing a hardened material of the adhesive according to any one of claims 8 to 13. A method for producing a solution of a hydroxyl-terminated urethane prepolymer, which manufactures the solution of a hydroxyl-terminated urethane prepolymer according to claim 2, wherein the hydroxyl-containing terminal urethane prepolymer is prepared The manufacturing method of the solution of the ester prepolymer has: The step of reacting one or more polyols (HA) with a number average molecular weight of 1000 or more and one or more polyisocyanates (N) in excess of isocyanate groups to form isocyanate group-terminated urethane prepolymers (UPN) ;as well as The obtained isocyanate group-terminated urethane prepolymer (UPN) is combined with one or more active hydrogen group-containing compounds (HB) having a number average molecular weight of less than 1000 and having multiple active hydrogen groups in one molecule. ) The steps of the reaction. A manufacturing method of an adhesive sheet, which manufactures the adhesive sheet according to claim 14, wherein the manufacturing method of the adhesive sheet includes: The step of mixing at least the solution of the hydroxyl-containing terminal urethane prepolymer with the polyfunctional isocyanate compound (I) to prepare an adhesive having a solid content concentration of 80% by mass or more; The step of applying the adhesive on the substrate sheet to form a coating layer; and The step of drying the coating layer, The viscosity of the adhesive at 25° C. at the time of application is 5000 mPa·s or less.

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