CN110494527B - Adhesive, adhesive sheet, and method for producing hydroxyl-terminated urethane prepolymer - Google Patents

Adhesive, adhesive sheet, and method for producing hydroxyl-terminated urethane prepolymer Download PDF

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CN110494527B
CN110494527B CN201980001763.9A CN201980001763A CN110494527B CN 110494527 B CN110494527 B CN 110494527B CN 201980001763 A CN201980001763 A CN 201980001763A CN 110494527 B CN110494527 B CN 110494527B
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active hydrogen
adhesive
group
hydroxyl
hydrogen group
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CN110494527A (en
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斋藤秀平
户根嘉孝
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Toyochem Co Ltd
Artience Co Ltd
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Toyo Ink SC Holdings Co Ltd
Toyochem Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J175/00—Adhesives based on polyureas or polyurethanes; Adhesives based on derivatives of such polymers
    • C09J175/04—Polyurethanes
    • C09J175/08—Polyurethanes from polyethers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/08—Processes
    • C08G18/10—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
    • C08G18/12—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step using two or more compounds having active hydrogen in the first polymerisation step
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/30—Low-molecular-weight compounds
    • C08G18/32—Polyhydroxy compounds; Polyamines; Hydroxyamines
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/48—Polyethers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/65—Low-molecular-weight compounds having active hydrogen with high-molecular-weight compounds having active hydrogen
    • C08G18/66—Compounds of groups C08G18/42, C08G18/48, or C08G18/52
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
    • C08G18/72—Polyisocyanates or polyisothiocyanates
    • C08G18/74—Polyisocyanates or polyisothiocyanates cyclic
    • C08G18/75—Polyisocyanates or polyisothiocyanates cyclic cycloaliphatic
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
    • C09J11/02—Non-macromolecular additives
    • C09J11/06—Non-macromolecular additives organic
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J7/00—Adhesives in the form of films or foils
    • C09J7/30—Adhesives in the form of films or foils characterised by the adhesive composition
    • C09J7/38—Pressure-sensitive adhesives [PSA]
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00—Specific properties of additives
    • C08K2201/017—Additives being an antistatic agent

Abstract

The invention provides an adhesive which has good pot life and initial hardening, can form an adhesive layer with good wettability and substrate adhesion, and has good removability even being placed in a high-temperature and high-humidity environment. The adhesive comprises a reaction product of a hydroxyl-terminated Urethane Prepolymer (UPH) and one or more polyisocyanates (N), wherein the hydroxyl-terminated Urethane Prepolymer (UPH) is a reaction product of a plurality of active hydrogen group-containing compounds (HX) including a polyether polyol (HA) having a number average molecular weight of 1650 or more per 1 functional group and an active hydrogen group-containing compound (HB) having a number average molecular weight of 300 or less per 1 functional group and having a plurality of active hydrogen groups in one molecule. The active hydrogen group-containing compound (HB) includes an active hydrogen group-containing compound containing only a primary hydroxyl group as an active hydrogen group.

Description

Adhesive, adhesive sheet, and method for producing hydroxyl-terminated urethane prepolymer
Technical Field
The present invention relates to an adhesive, an adhesive sheet, and a method for producing a hydroxyl-terminated urethane prepolymer.
Background
Conventionally, as surface protection sheets for various members, adhesive sheets having an adhesive layer formed on a base sheet have been widely used. Examples of the adhesive include acrylic adhesives, silicone adhesives, and urethane adhesives. Acrylic adhesives have excellent adhesion, but have strong adhesion, and therefore have poor removability after being attached to an adherend. In particular, after a lapse of time under a high-temperature and high-humidity environment, the removability further decreases due to an increase in adhesive force, and the adherend tends to be easily contaminated by the adhesive remaining on the surface of the adherend after removability. Regarding the silicone adhesive, there are also the following concerns: the silicone resin having a relatively low molecular weight is likely to be adsorbed on the surface of a device such as an electronic component, causing a problem. In contrast, the urethane adhesive has good adhesion to an adherend, is excellent in removability, and is not easily volatile.
In the present specification, the "adhesive" is an adhesive having removability (removable adhesive), and the "adhesive sheet" is an adhesive sheet having removability (removable adhesive sheet).
Flat panel displays such as Liquid Crystal Displays (LCDs) and Organic electroluminescent displays (OELDs), and touch panel displays in which the flat panel displays and touch panels are combined are widely used in electronic devices such as Televisions (TVs), Personal Computers (PCs), mobile phones, and portable information terminals.
The urethane adhesive sheet can be preferably used as a surface protective sheet for flat panel displays, touch panel displays, and substrates produced or used in the production process of these (glass substrates, ITO/glass substrates having an Indium Tin Oxide (ITO) film formed on a glass substrate, and the like), optical members, and the like.
The following methods are known as a method for producing a urethane adhesive: a method of using a hydroxyl-terminated urethane prepolymer which is a reaction product of an active hydrogen group-containing compound such as a polyol and a polyisocyanate, and a polyfunctional isocyanate compound; and a method of reacting a polyol with a polyfunctional isocyanate compound in one shot (one shot method) without using a hydroxyl-terminated urethane prepolymer.
A general method for producing an adhesive sheet includes: a coating step of coating the adhesive on a substrate sheet; a heating step of forming an adhesive layer containing a cured product of an adhesive by heating and drying the formed coating layer; a winding step of winding the obtained adhesive sheet around a winding core to form an adhesive sheet roll; and a curing step of curing the adhesive sheet roller.
Documents of the prior art
Patent document
Patent document 1: japanese patent No. 5501489
Patent document 2: japanese patent laid-open No. 2016-138237
Patent document 3: japanese patent laid-open No. 2016-204468
Disclosure of Invention
Problems to be solved by the invention
The urethane adhesive is cured immediately after production, but if the initial curing property is too high, there is a concern that: the pot life (pot life) becomes short, and the viscosity of the adhesive becomes too high to be uniformly applied until the adhesive is applied to the substrate sheet. If the initial curing property of the urethane adhesive is too low, there is a concern that: the coating layer or the adhesive layer is affected by hot air during heating and drying of the coating layer or by mechanical stress applied during winding and curing of the adhesive sheet obtained after heating and drying, and thus, a difference in surface appearance such as a core step, orange peel defect, curl, and the like occurs in the adhesive layer. The urethane adhesive preferably has a good pot life and good initial curability.
The pressure-sensitive adhesive sheet preferably has good adhesion of the pressure-sensitive adhesive layer to the substrate sheet (also referred to as substrate adhesion). The pressure-sensitive adhesive sheet preferably has good adhesion to a substrate and good removability to be easily removable from an adherend when removed from the adherend. The adhesive sheet is preferably free from contamination of an adherend in which an adhesive component remains on the surface of the adherend after peeling off even when exposed to a high-temperature and high-humidity environment.
The adhesive layer preferably has good wettability to an adherend such as glass, and air bubbles are not involved in the adhesion interface when the adhesive sheet is adhered to the adherend. In the urethane adhesive, a plasticizer may be added to improve wettability. However, when the plasticizer is added in a large amount, particularly when the adhesive sheet is exposed to a high-temperature and high-humidity environment, there is a possibility that the adherend is contaminated with an adhesive component remaining on the surface of the adherend after the re-peeling of the adhesive sheet. Therefore, the amount of plasticizer added is preferably small, and more preferably no plasticizer is added. The urethane adhesive preferably has good wettability even in a formulation composition in which the amount of the plasticizer added is small/the plasticizer is preferably not added.
Patent documents 1 to 3 are cited as related documents of the present invention.
Patent document 1 discloses a urethane adhesive containing a polyurethane resin obtained by curing a composition containing a plurality of polyols (a) and a polyfunctional isocyanate compound (B), wherein the plurality of polyols (a) include a polyol (a1) having three OH groups and a polyol (a2) having a number average molecular weight (Mn) of 8000 to 20000 and three or more OH groups and a number average molecular weight (Mn) of 5000 or less (claim 1).
Patent document 2 discloses a polyol composition for adhesives, which contains the following polyol (a1) and is used to react with a polyisocyanate compound (B) to obtain an adhesive (claim 1).
Polyol (a 1): a polyoxyalkylene polyol having a number of functional groups of 3 or more, a number average molecular weight (Mn) of 500 to 2500 per 1 functional group, and a content of oxyethylene groups of 16 mol% or more based on the total amount of oxyalkylene groups.
Patent document 2 discloses a set for an adhesive, comprising a main composition contained in a1 st container and a curing agent composition contained in a2 nd container,
the main agent composition is the polyol composition for the adhesive,
the hardener composition comprises a polyisocyanate compound (B),
one or both of the main agent composition and the hardener composition contain a catalyst (C) (technical scheme 5).
Patent document 3 discloses a urethane adhesive containing a urethane prepolymer obtained by using a polyether diol a having an unsaturation degree of 0.07meq/g or less and a number average molecular weight (Mn) of 3000 to 30000 and a polyisocyanate C, wherein the ratio of NCO groups of the polyisocyanate C to the total amount of OH groups of the polyether diol a is in the range of 0.85 to 1.15 (molar ratio) (claim 9).
The symbols of the components described in patent documents 1 to 3 are those described in these documents, and are unrelated to the symbols used for the components of the present invention.
The urethane adhesives described in patent documents 1 and 2 are obtained by a single-pass method. In general, an adhesive layer using a urethane adhesive obtained by a single process is hard, and the surface smoothness of the adhesive layer tends to be easily deteriorated by curing shrinkage.
In the urethane adhesive described in patent document 3, polyether glycol a having a number average molecular weight (Mn) of 1500 to 15000 per 1 functional group is used as a raw material polyol of a urethane prepolymer. In the case of using such a relatively long-chain polyol as a raw material polyol for a urethane prepolymer, there are the following orientations: the wettability of the adhesive layer can be improved, but the initial hardenability of the adhesive is lowered and the removability of the adhesive layer is lowered.
The present invention has been made in view of the above circumstances, and an object thereof is to provide an adhesive agent which has good pot life and initial curability, and which can form an adhesive layer having good wettability and substrate adhesion and good removability even when placed in a high-temperature and high-humidity environment, and an adhesive sheet using the same.
Means for solving the problems
The adhesive of the present invention comprises:
a hydroxyl-terminated Urethane Prepolymer (UPH) which is a reaction product of a plurality of active hydrogen group-containing compounds (HX) comprising a polyether polyol (HA) having a number average molecular weight per 1 functional group of 1650 or more and an active hydrogen group-containing compound (HB) having a number average molecular weight per 1 functional group of 300 or less and having a plurality of active hydrogen groups in one molecule, and one or more polyisocyanates (N); and
a polyfunctional isocyanate compound (I), and
the active hydrogen group-containing compound (HB) includes an active hydrogen group-containing compound containing only a primary hydroxyl group as an active hydrogen group.
The adhesive sheet of the present invention comprises a substrate sheet and an adhesive layer containing a cured product of the adhesive of the present invention.
The method for producing a hydroxyl-terminated urethane prepolymer of the present invention comprises: a step in which at least one polyether polyol (HA) having a number average molecular weight (Mn) per 1 functional group of 1650 or more is reacted with at least one polyisocyanate (N) at a ratio of excess isocyanate groups to produce an isocyanate group-terminated Urethane Prepolymer (UPN); and
reacting the isocyanate group-terminated Urethane Prepolymer (UPN) with one or more active hydrogen group-containing compounds (HB) having a number average molecular weight (Mn) per 1 functional group of 300 or less and having a plurality of active hydrogen groups in one molecule.
In the present specification, "Mw" is a polystyrene-equivalent weight average molecular weight determined by Gel Permeation Chromatography (GPC) measurement. "Mn" is a number average molecular weight in terms of polystyrene determined by GPC measurement. These can be measured by the method described in [ example ].
ADVANTAGEOUS EFFECTS OF INVENTION
The present invention provides an adhesive which has good pot life and initial curability, and which can form an adhesive layer having good wettability and substrate adhesion and good removability even when placed in a high-temperature and high-humidity environment, and an adhesive sheet using the same.
Drawings
Fig. 1 is a schematic cross-sectional view of an adhesive sheet according to embodiment 1 of the present invention.
Fig. 2 is a schematic cross-sectional view of an adhesive sheet according to embodiment 2 of the present invention.
Detailed Description
The adhesive is a urethane adhesive comprising a hydroxyl-terminated Urethane Prepolymer (UPH) and a polyfunctional isocyanate compound (I), wherein the hydroxyl-terminated Urethane Prepolymer (UPH) is a reaction product of a plurality of active hydrogen group-containing compounds (HX) and one or more polyisocyanates (N).
In the present invention, the plurality of active hydrogen group-containing compounds (HX) include one or more polyether polyols (HA) having a number average molecular weight (Mn) of 1650 or more per 1 functional group and one or more active hydrogen group-containing compounds (HB) having a number average molecular weight (Mn) of 300 or less per 1 functional group and having a plurality of active hydrogen groups in one molecule.
The adhesive sheet of the present invention is a urethane adhesive sheet comprising a substrate sheet and an adhesive layer containing a cured product of the adhesive of the present invention.
[ Adhesives ]
(hydroxyl-terminated Urethane Prepolymer (UPH))
The hydroxyl-terminated Urethane Prepolymer (UPH) is a reaction product obtained by copolymerizing a plurality of active hydrogen group-containing compounds (HX) with one or more polyisocyanates (N). The copolymerization can be carried out in the presence of one or more catalysts, if desired. If necessary, one or more solvents may be used in the copolymerization reaction.
The hydroxyl-terminated Urethane Prepolymer (UPH) is preferably a reaction product of an isocyanate-terminated Urethane Prepolymer (UPN) which is a reaction product of a polyether polyol (HA) and a polyisocyanate (N), and an active hydrogen group-containing compound (HB).
In the present invention, the plurality of active hydrogen group-containing compounds (HX) contain a relatively long-chain polyether polyol (HA) and a relatively short-chain active hydrogen group-containing compound (HB).
< polyether polyol (HA) >
The polyether polyol (HA) is a relatively long-chain polyether polyol having a number average molecular weight (Mn) per 1 functional group of 1650 or more and a number average molecular weight (Mn) per 1 functional group greater than that of an active hydrogen group-containing compound generally used as a raw material of a urethane (pre) polymer.
As the polyether polyol (HA), known ones can be used. The polyether polyol (HA) includes a compound (addition polymer) obtained by addition polymerization of one or more types of oxirane compounds using an active hydrogen group-containing compound having a plurality of active hydrogen groups in one molecule as an initiator.
Examples of the initiator include hydroxyl group-containing compounds and amines. Specifically, there may be mentioned: difunctional initiators such as Ethylene Glycol (EG), Propylene Glycol (PG), 1, 4-butanediol, neopentyl Glycol, butylethylpentanediol, N-aminoethylethanolamine, isophoronediamine, and xylylenediamine; trifunctional initiators such as glycerol, trimethylolpropane and triethanolamine; tetrafunctional initiators such as pentaerythritol, ethylenediamine and aromatic diamines; pentafunctional initiators such as diethylenetriamine, and the like.
Examples of the oxirane compound include: alkylene Oxides (AO) such as Ethylene Oxide (EO), Propylene Oxide (PO) and Butylene Oxide (BO); tetrahydrofuran (THF), and the like.
As the polyether polyol (HA), an alkylene oxide adduct of an active hydrogen group-containing compound (also referred to as "polyoxyalkylene polyol") is preferable. Among them, bifunctional polyether polyols such as Polyethylene Glycol (PEG), Polypropylene Glycol (PPG), and polyalkylene glycols such as PPG (PPG-EO) and polytetramethylene Glycol having Ethylene Oxide (EO) added to the end thereof are preferable; trifunctional polyether polyols such as alkylene oxide adducts of glycerin, and the like.
The unsaturation degree of the polyether polyol (HA) is preferably low. The unsaturation degree means the total amount of unsaturated groups contained in each 1g of polyether polyol, and corresponds to the amount of impurity monool. By using a high-purity material having a low degree of unsaturation, the initial curing properties of the adhesive become good, and in particular, when the adhesive sheet is exposed to a high-temperature and high-humidity environment, contamination of an adherend in which an adhesive component remains on the surface of the adherend after re-peeling of the adhesive sheet can be suppressed. The unsaturation degree of the polyether polyol (HA) is preferably 0.07meq/g or less, more preferably 0.04meq/g or less, and particularly preferably 0.01meq/g or less.
In the present specification, unless otherwise specified, the unsaturation degree of the polyol is a value measured in accordance with Japanese Industrial Standard (JIS) K15576.7.
< Compound (HB) containing active Hydrogen group >
The active hydrogen group-containing compound (HB) is an active hydrogen group-containing compound having a number average molecular weight (Mn) per 1 functional group of 300 or less and a number average molecular weight (Mn) per 1 functional group smaller than that of a relatively short chain of an active hydrogen group-containing compound generally used as a raw material for urethane (pre) polymers.
As the active hydrogen group, there can be mentioned: hydroxyl group, mercapto group, and amino group (in the present specification, amino group includes imino group unless otherwise specified). As the active hydrogen group-containing compound (HB), there can be mentioned: polyols having a plurality of hydroxyl groups in one molecule, polyamines having a plurality of amino groups in one molecule, aminoalcohols having an amino group and a hydroxyl group in one molecule, polythiols having a plurality of mercapto groups in one molecule, and the like. These may be used singly or in combination. The active hydrogen group-containing compound (HB) may be a non-polymer or a polymer.
Among them, polyhydric alcohols are preferable. Polyamines and polythiols have high reactivity and short pot life, and therefore, when these are used, they are preferably used in combination with a polyol. In addition, in the case where the polyol contains a secondary hydroxyl group, the initial curing properties of the urethane adhesive are not improved, and therefore, the active hydrogen group-containing compound (HB) preferably contains a primary hydroxyl group having appropriate reactivity in terms of pot life and initial curing properties.
Examples of non-polymeric polyols include: ethylene Glycol (EG), Propylene Glycol (PG), diethylene glycol, triethylene glycol, 1, 3-butanediol, 1, 4-butanediol, neopentyl 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 referred to as "1, 3-octanediol"), 1, 8-octanediol, 1, 9-nonanediol, 2-methyl-1, 8-octanediol, 1, 8-decanediol, octadecanediol, glycerin, Trimethylolpropane (TMP), pentaerythritol, hexanetriol, and the like.
As the polyol which can be used as the polymer of the active hydrogen group-containing compound (HB), there can be mentioned: polyester polyols, polyether polyols, polyacrylic polyols, polycaprolactone polyols, polycarbonate polyols, castor oil polyols, and the like. Among these, polyester polyols, polyether polyols, and combinations thereof are preferable.
As the polyester polyol usable as the active hydrogen group-containing compound (HB), known ones can be used. Examples of the polyester polyol include compounds (esterified products) obtained by esterification of one or more polyol components and one or more acid components.
As the polyol component of the raw material, there can be mentioned: ethylene Glycol (EG), Propylene Glycol (PG), diethylene glycol, 1, 3-butanediol, 1, 4-butanediol, neopentyl 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, 3-octanediol), 1, 8-octanediol, 1, 9-nonanediol, 2-methyl-1, 8-octanediol, 1, 8-decanediol, octadecanediol, glycerol, trimethylolpropane, pentaerythritol, hexanetriol, and the like.
As the acid component of the raw material, there can be mentioned: succinic acid, methylsuccinic acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, 1, 12-dodecanedioic acid, 1, 14-tetradecanedioic acid, dimer acid, 2-methyl-1, 4-cyclohexanedicarboxylic acid, 2-ethyl-1, 4-cyclohexanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, 1, 4-naphthalenedicarboxylic acid, 4' -biphenyldicarboxylic acid, anhydrides thereof, and the like.
As the polyether polyol usable as the active hydrogen group-containing compound (HB), known ones can be used. The polyether polyol includes a compound (addition polymer) obtained by addition polymerization of one or more types of oxirane compounds using an active hydrogen group-containing compound having a plurality of active hydrogen groups in one molecule as an initiator. The initiator and the oxirane compound may be the same as those exemplified for the polyether polyol (HA).
As the polyether polyol which can be used as the active hydrogen group-containing compound (HB) similarly to the polyether polyol (HA), an alkylene oxide adduct (polyoxyalkylene polyol) of the active hydrogen group-containing compound is preferable. Among them, preferable are bifunctional polyether polyols such as polyethylene glycol (PEG), polypropylene glycol (PPG), and PPG (PPG-EO) having Ethylene Oxide (EO) added to the end, and polyalkylene glycols such as polytetramethylene glycol; trifunctional polyether polyols such as alkylene oxide adducts of glycerin, and the like.
As polyamines usable as the active hydrogen group-containing compound (HB), there can be mentioned: ethylenediamine, 1, 2-propylenediamine, 1, 3-propylenediamine, 1, 4-butylenediamine, 1, 5-pentylenediamine, 1, 6-hexylenediamine, 1, 7-heptylenediamine, 1, 8-octylenediamine, 1, 9-nonylenediamine, 1, 10-decylenediamine, 1, 12-dodecylenediamine, 1, 14-tetradecanediamine, 1, 16-hexadecylenediamine, hexamethylenediamine, trimethylhexamethylenediamine, iminobispropylamine, methyliminobispropylamine, 1, 5-diamino-2-methylpentane, isophoronediamine, 1, 3-bisaminomethylcyclohexane, 1-cyclohexylamino-3-aminopropane, 3-aminomethyl-3, 3, 5-trimethyl-cyclohexylamine, 1, 4-butylenediamine, 1, 5-tetramethylenediamine, 1, 6-hexamethylenediamine, 1, 7-heptamethylenediamine, 1, 16-hexamethylenediamine, 3-aminomethyl-3, 5-methyl-cyclohexylamine, 1, 2-dimethylhexamethylenediamine, and mixtures thereof, Aliphatic polyamines such as dimethylene diamine (MXDA), hexamethylene diamine carbamate, diethylene triamine, triethylene tetramine, tetraethyl pentamine, and pentaethylene hexamine with a norbornane skeleton; aromatic polyamines such as 3,3 '-dichloro-4, 4' -diaminodiphenylmethane (MOCA), 4 '-diaminodiphenylmethane, 2, 4' -diaminodiphenylmethane, 3 '-diaminodiphenylmethane, 3, 4' -diaminodiphenylmethane, 2 '-diaminobiphenyl, 3' -diaminobiphenyl, 2, 4-diaminophenol, 2, 5-diaminophenol, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2, 3-tolylenediamine, 2, 4-tolylenediamine, 2, 5-tolylenediamine, 2, 6-tolylenediamine, 3, 4-tolylenediamine, and diethyltolylenediamine.
As the amino alcohol that can be used as the active hydrogen group-containing compound (HB), there can be mentioned: monoamines having a hydroxyl group such as monoethanolamine, diethanolamine, 2-amino-2-methyl-1-propanol, tris (hydroxymethyl) aminomethane and 2-amino-2-ethyl-1, 3-propanediol; diamines having a hydroxyl group such as N- (2-hydroxypropyl) ethanolamine, and the like.
As polythiols usable as the active hydrogen group-containing compound (HB), there can be mentioned: methanedithiol, 1, 3-butanedithiol, 1, 4-butanedithiol, 2, 3-butanedithiol, 1, 2-benzenedithiol, 1, 3-benzenedithiol, 1, 4-benzenedithiol, 1, 10-decanedithiol, 1, 2-ethanedithiol, 1, 6-hexanedithiol, 1, 9-nonanedithiol, 1, 8-octanedithiol, 1, 5-pentanedithiol, 1, 2-propanedithiol, 1, 3-propanedithiol, toluene-3, 4-dithiol, 3, 6-dichloro-1, 2-benzenedithiol, 1, 5-naphthalenedithiol, 1, 2-benzenedimethanethiol, 1, 3-benzenedimethanethiol, 1, 4-benzenedimethanethiol, 1, 3-benzenedithiol, 1, 4-benzenedimethanethiol, 1, 2-benzenedithiol, 1, 2-benzenedimethanethiol, 1, 2,1, 2,1, and benzene dimethanethiol, 4, 4' -thiobisbenzenethiol, 2, 5-dimercapto-1, 3, 4-thiadiazole, 1, 8-dimercapto-3, 6-dioxaoctane, 1, 5-dimercapto-3-thiapentane, 2-di-n-butylamino-4, 6-dimercapto-s-triazine, and thiol group-terminated polymers (such as polythioether polymers).
In general, a plasticizer is sometimes added to a urethane adhesive in order to improve wettability. However, when the plasticizer is added in a large amount, particularly when the adhesive sheet is exposed to a high-temperature and high-humidity environment, there is a possibility that the adherend is contaminated with an adhesive component remaining on the surface of the adherend after the re-peeling of the adhesive sheet.
In the present invention, by using a relatively long-chain polyether polyol (HA) having a number average molecular weight (Mn) of 1650 or more per 1 functional group, preferably an Alkylene Oxide (AO) group-containing relatively long-chain polyether polyol (HA), as a raw material active hydrogen group-containing compound of a hydroxyl-terminated Urethane Prepolymer (UPH), it is possible to form an adhesive layer having good wettability to an adherend even with a small amount of plasticizer added/preferably a formulated composition without adding a plasticizer. For example, an adhesive layer can be formed that is less likely to cause air bubbles to be involved in the adhesion interface when the adhesive sheet is adhered to an adherend such as a glass substrate or an ITO/glass substrate. It is considered that the organic group bonded to an oxygen atom, preferably an alkylene group, constituting an ether bond is relatively large in number, and thus the same action and effect as those of the plasticizer are exhibited.
When a polyether polyol (HA) having a relatively long chain is used as a raw material of the hydroxyl-terminated Urethane Prepolymer (UPH), there are the following orientations: the wettability of the adhesive layer is improved, while the initial hardenability of the adhesive is reduced and the removability of the adhesive layer is reduced. The higher the number average molecular weight (Mn) per 1 functional group of the polyether polyol (HA), the greater the tendency.
From the viewpoint of improving the wettability of the adhesive layer, the number average molecular weight (Mn) per 1 functional group of the polyether polyol (HA) is preferably 2000 or more, and more preferably 3000 or more.
In the present invention, by using the relatively short-chain active hydrogen group-containing compound (HB) as a raw material of the hydroxyl-terminated Urethane Prepolymer (UPH), it is possible to improve the reduction in initial curability of the adhesive and the reduction in removability of the adhesive layer, which are caused by using the relatively long-chain polyether polyol (HA).
The polyether polyol (HA) preferably HAs a number average molecular weight (Mn) of 2000 to 10000, more preferably 3000 to 9000, per 1 functional group, from the viewpoint of balance among improvement of wettability of the adhesive layer, initial curing properties of the adhesive, and removability of the adhesive layer.
The number average molecular weight (Mn) per 1 functional group of the active hydrogen group-containing compound (HB) is preferably 30 to 300, more preferably 30 to 100, in terms of effectively improving the decrease in initial hardenability and the decrease in removability of the adhesive layer due to the use of a relatively long-chain polyether polyol (HA).
The one or more polyether polyols (HA) may comprise difunctional polyether polyols and/or trifunctional or higher polyether polyols. Likewise, the one or more active hydrogen group-containing compounds (HB) may contain a difunctional active hydrogen group-containing compound and/or a trifunctional or more active hydrogen group-containing compound.
In general, the bifunctional active hydrogen group-containing compound has two-dimensional crosslinkability and can impart appropriate flexibility to the adhesive layer. The trifunctional or higher active hydrogen group-containing compound has three-dimensional crosslinkability and can impart an appropriate hardness to the adhesive layer.
By selecting the number of functional groups (the number of active hydrogen groups) of each of the one or more polyether polyols (HA) and the one or more active hydrogen group-containing compounds (HB), the properties of the urethane adhesive, such as adhesive force, cohesive force, and removability, can be adjusted. The number of functional groups of each material can be selected according to the application, etc., so that the properties such as adhesive force, cohesive force, and removability are in a preferable range. The one or more polyether polyols (HA) preferably include a trifunctional or higher polyether polyol in terms of easy compatibility between the adhesive force and the removability. The one or more active hydrogen group-containing compounds (HB) are preferably difunctional active hydrogen group-containing compounds in terms of easily achieving both reaction stability and cohesive force.
The plurality of active hydrogen group-containing compounds (HX) that are the starting materials of the hydroxyl-terminated Urethane Prepolymer (UPH) may contain one or more known active hydrogen group-containing compounds other than the polyether polyol (HA) and the active hydrogen group-containing compound (HB).
As related documents of the present invention, there are patent documents 1 to 3 listed in the "background art". These documents describe a polyol having a relatively long chain with a number average molecular weight (Mn) of 1650 or more per 1 functional group, but do not describe or suggest the use of a compound (HB) having an active hydrogen group in a relatively short chain with a number average molecular weight (Mn) of 300 or less per 1 functional group. The urethane adhesives described in patent documents 1 and 2 are obtained by a single-pass method, and a hydroxyl-terminated urethane prepolymer is not used.
< polyisocyanate (N) >
As the polyisocyanate (N), known ones can be used, and there can be mentioned: aromatic polyisocyanate, aliphatic polyisocyanate, alicyclic polyisocyanate, and the like.
Examples of the aromatic polyisocyanate include: 1, 3-phenylene diisocyanate, 4 '-diphenyl diisocyanate, 1, 4-phenylene diisocyanate, 4' -diphenylmethane diisocyanate, 2, 4-tolylene diisocyanate, 2, 6-tolylene diisocyanate, 4 '-toluidine diisocyanate, 2, 4, 6-triisocyanate toluene, 1, 3, 5-triisocyanate benzene, dianisidine diisocyanate, 4' -diphenyl ether diisocyanate and 4, 4 '-triphenylmethane triisocyanate, omega' -diisocyanate-1, 3-dimethylbenzene, omega '-diisocyanate-1, 4-dimethylbenzene, omega' -diisocyanate-1, 4-diethylbenzene, 1, 4-tetramethylxylylene diisocyanate, and 1, 3-tetramethylxylylene diisocyanate.
Examples of the aliphatic polyisocyanate include: trimethylene Diisocyanate, tetramethylene Diisocyanate, Hexamethylene Diisocyanate (HDI), pentamethylene Diisocyanate, 1, 2-propylene Diisocyanate, 2, 3-butylene Diisocyanate, 1, 3-butylene Diisocyanate, dodecamethylene Diisocyanate, 2, 4, 4-trimethylhexamethylene Diisocyanate, and the like.
Examples of the alicyclic polyisocyanate include: isophorone Diisocyanate (IPDI), 1, 3-cyclopentane Diisocyanate, 1, 3-cyclohexane Diisocyanate, 1, 4-cyclohexane Diisocyanate, methyl-2, 6-cyclohexane Diisocyanate, 4' -methylenebis (cyclohexyl isocyanate), 1, 4-bis (isocyanatomethyl) cyclohexane, and the like.
Further, as the polyisocyanate, there can be mentioned: trimethylolpropane adduct, biuret (biuret) body, allophanate (allophanate) body, trimer (the trimer including an isocyanurate ring), and the like of the polyisocyanate.
The polyisocyanate (N) is preferably 4, 4' -diphenylmethane diisocyanate, Hexamethylene Diisocyanate (HDI), isophorone diisocyanate (IPDI), or the like. As will be described in detail later, the one or more polyisocyanates (N) preferably comprise isophorone diisocyanate (IPDI).
The preferred raw material compounding ratio of the hydroxyl-terminated Urethane Prepolymer (UPH) is as follows.
The raw material compounding ratio is preferably determined so that the ratio (NCO/H) of the number of moles of isocyanate groups (NCO) in the polyisocyanate (N) to the total number of moles of active hydrogen groups (H) in the plurality of active hydrogen group-containing compounds (HX) is 0.20 to 0.84, more preferably 0.40 to 0.80. The following tendency is exhibited: the closer the NCO/H is to 1, the more likely it is to gel during synthesis of a hydroxyl-terminated Urethane Prepolymer (UPH). When the NCO/H ratio is 0.84 or less, gelation at the time of synthesizing a hydroxyl-terminated Urethane Prepolymer (UPH) can be effectively suppressed.
From the viewpoints of the effect of improving the wettability of the adhesive layer by using the polyether polyol (HA), the effect of improving the initial curing properties of the adhesive and the releasability of the adhesive layer by using the active hydrogen group-containing compound (HB), and the stable synthesis of the desired hydroxyl-terminated Urethane Prepolymer (UPH),
preferably: the amount of the one or more active hydrogen group-containing compounds (HB) is 0.5 to 40 parts by mass and the amount of the one or more polyisocyanates (N) is 1.0 to 20 parts by mass based on 100 parts by mass of the one or more polyether polyols (HA).
More preferably: the amount of the one or more active hydrogen group-containing compounds (HB) is 1.0 to 20 parts by mass and the amount of the one or more polyisocyanates (N) is 3.0 to 10 parts by mass based on 100 parts by mass of the one or more polyether polyols (HA).
< catalyst >
If desired, more than one catalyst may be used in the polymerization of the hydroxyl-terminated Urethane Prepolymer (UPH). As the catalyst, known ones can be used, and examples thereof include tertiary amine compounds, organometallic compounds and the like.
Examples of the tertiary amine compound include: triethylamine, triethylenediamine, and 1, 8-Diazabicyclo (5, 4, 0) -undecene-7 (1, 8-Diazabicyclo (5, 4, 0) -undecene-7, DBU), and the like.
Examples of the organometallic compound include tin compounds and non-tin compounds.
Examples of the tin-based compound include: dibutyltin dichloride, Dibutyltin oxide, Dibutyltin dibromide, Dibutyltin dimaleate (dibutyl tin dimaleate), Dibutyltin Dilaurate (DBTDL), Dibutyltin diacetate, Dibutyltin sulfide, tributyltin oxide, tributyltin acetate, triethyltin acetate (triethyl acetate), tributyltin acetate (tributyl acetate), dioctyltin oxide, tributyltin chloride, tributyltin trichloroacetate, and tin 2-ethylhexanoate, and the like.
Examples of the non-tin compound include: titanium systems such as dibutyltitanium dichloride, tetrabutyl titanate and butoxytitanium trichloride; lead systems such as lead oleate, lead 2-ethylhexoate, lead benzoate, and lead naphthenate; iron series such as iron 2-ethylhexanoate and iron acetylacetonate; cobalt systems such as cobalt benzoate and cobalt 2-ethylhexanoate; zinc systems such as zinc naphthenate and zinc 2-ethylhexanoate; zirconium-based compounds such as zirconium naphthenate.
The kind and amount of the catalyst to be added can be suitably designed within a range in which the reaction proceeds well.
Depending on the reactivity of the plurality of active hydrogen group-containing compounds (HX), gelation or clouding of the reaction solution may easily occur in a single catalyst system. In such a case, by using two catalysts, it is easy to control the reaction (e.g., reaction rate, etc.), so that the problem can be solved. The combination of the two catalysts is not particularly limited, and there may be exemplified: tertiary amine/organic metal system, tin system/non-tin system, and tin system/tin system, etc. Tin-based/tin-based is preferred, and dibutyltin dilaurate and tin 2-ethylhexanoate are more preferred.
The mass ratio of tin 2-ethylhexanoate to dibutyltin dilaurate (tin 2-ethylhexanoate/dibutyltin dilaurate) is not particularly limited, but is preferably more than 0 and less than 1, and more preferably 0.2 to 0.6. If the mass ratio is less than 1, the balance of the catalyst activity is good, gelation and clouding of the reaction solution are effectively suppressed, and the polymerization stability is further improved.
< solvent >
If necessary, one or more solvents may be used for the polymerization of the hydroxyl-terminated Urethane Prepolymer (UPH). As the solvent, known ones can be used, and there can be mentioned: methyl ethyl ketone, ethyl acetate, toluene, xylene, acetone, and the like. In terms of solubility of the hydroxyl-terminated Urethane Prepolymer (UPH), boiling point of the solvent, and the like, ethyl acetate, toluene, and the like are particularly preferable.
< method for polymerizing hydroxyl-terminated Urethane Prepolymer (UPH) >
The polymerization method of the hydroxyl-terminated Urethane Prepolymer (UPH) is not particularly limited, and known polymerization methods such as bulk polymerization and solution polymerization can be used.
Examples of the polymerization order of the hydroxyl-terminated Urethane Prepolymer (UPH) include:
sequence 1) a sequence in which one or more polyether polyols (HA), one or more active hydrogen group-containing compounds (HB), one or more polyisocyanates (N), optionally one or more catalysts, and optionally one or more solvents are charged into a flask together;
sequence 2) a sequence in which one or more polyether polyols (HA), one or more active hydrogen group-containing compounds (HB), optionally one or more catalysts, and optionally one or more solvents are charged into a flask, and one or more polyisocyanates (N) are added dropwise thereto;
and 3) a step of charging one or more polyether polyols (HA), one or more polyisocyanates (N), optionally one or more catalysts, and optionally one or more solvents into a flask together, reacting the polyisocyanate (N) with the polyether polyol (HA) at an excess isocyanate group ratio to form an isocyanate group-terminated Urethane Prepolymer (UPN), and then adding one or more active hydrogen group-containing compounds (HB).
The reaction temperature when the catalyst is used is preferably less than 100 ℃, more preferably 50 to 95 ℃, and particularly preferably 60 to 85 ℃. If the reaction temperature is 100 ℃ or higher, the following concerns may arise: 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 ℃ or higher, more preferably 110 ℃ or higher.
In the sequences 1) and 2), the polyether polyol (HA) having a relatively long chain and the active hydrogen group-containing compound (HB) having a relatively short chain are mixed with the polyisocyanate (N) at the same time. In the method, the following steps are performed: the active hydrogen group-containing compound (HB) having a relatively short chain with high reactivity reacts with the polyisocyanate (N) in preference to the polyether polyol (HA) having a relatively long chain with low reactivity. In such a case, there is a fear that: polyether polyol (HA) having a relatively long chain with low reactivity remains in an unreacted state, and the reaction liquid becomes cloudy. When the condition that the number of moles of isocyanate groups is excessive relative to the total number of moles of active hydrogen groups is set to eliminate the relatively long-chain polyether polyol (HA) remaining in an unreacted state, there is a concern that: the reaction liquid is gelled by causing an undesirable reaction between the isocyanate group-terminated urethane prepolymer formed by first reacting the relatively short chain active hydrogen group-containing compound (HB) with the polyisocyanate (N) and the relatively short chain active hydrogen group-containing compound (HB) having high reactivity.
The sequence 3) is preferable in terms of ease of reaction control. The aggregation using the order includes: a step of reacting one or more polyether polyols (HA) with one or more polyisocyanates (N) at an excess isocyanate group ratio to produce an isocyanate group-terminated Urethane Prepolymer (UPN); and a step of reacting the isocyanate group-terminated Urethane Prepolymer (UPN) with one or more active hydrogen group-containing compounds (HB).
In the sequence 3), only the polyether polyol (HA) having a relatively long chain with low reactivity is reacted with the polyisocyanate (N) in a state where the active hydrogen group-containing compound (HB) having a relatively short chain does not coexist, and then the obtained isocyanate group-terminated Urethane Prepolymer (UPN) is reacted with the active hydrogen group-containing compound (HB). In the above method, the desired hydroxyl-terminated Urethane Prepolymer (UPH) can be stably synthesized while suppressing gelation and clouding of the reaction solution.
Therefore, the hydroxyl-terminated Urethane Prepolymer (UPH) is preferably a reaction product of an isocyanate-terminated Urethane Prepolymer (UPN), which is a reaction product of a polyether polyol (HA) and a polyisocyanate (N), and an active hydrogen group-containing compound (HB).
In sequence 3), the one or more polyisocyanates (N) preferably comprise isophorone diisocyanate (IPDI). In such a case, the reaction can be easily controlled and a desired hydroxyl-terminated Urethane Prepolymer (UPH) can be stably synthesized.
(polyfunctional isocyanate Compound (I))
As the polyfunctional isocyanate compound (I), known ones can be used, and compounds exemplified as polyisocyanate (N) which is a raw material of the hydroxyl-terminated Urethane Prepolymer (UPH) (specifically, aromatic polyisocyanate, aliphatic polyisocyanate, aromatic aliphatic polyisocyanate, alicyclic polyisocyanate, and trimethylolpropane adduct/biuret/allophanate/trimer thereof) can be used.
(plasticizer (P))
As described above, in the present invention, even in the formulation composition in which the plasticizer (P) is added in a small amount/preferably in which the plasticizer (P) is not added, an adhesive having good wettability can be provided. Therefore, the plasticizer (P) is not an essential component for improving wettability in the adhesive of the present invention, but the adhesive of the present invention may optionally contain one or more plasticizers (P). In the case where the plasticizer (P) is added, the amount thereof can be suppressed to a low level. The amount of the plasticizer (P) may be, for example, 50 parts by mass or less (0 to 50 parts by mass), preferably 40 parts by mass or less (0 to 40 parts by mass), more preferably 30 parts by mass or less (0 to 30 parts by mass), still more preferably 20 parts by mass or less (0 to 20 parts by mass), particularly preferably 10 parts by mass or less (0 to 10 parts by mass), and most preferably 5 parts by mass or less (0 to 5 parts by mass) relative to 100 parts by mass of the hydroxyl-terminated Urethane Prepolymer (UPH).
The plasticizer (P) is not particularly limited, and is preferably an organic acid ester having a molecular weight of 250 to 1,000 from the viewpoint of compatibility with other components.
Examples of esters of mono-or polybasic acids with alcohols include: isostearyl laurate, isopropyl myristate, isocetyl myristate, octyldodecyl myristate, isostearyl palmitate, isocetyl stearate, octyldodecyl oleate, dibutyl phthalate, dioctyl phthalate, diheptyl phthalate, dibenzyl phthalate, butyl benzyl phthalate, diisodecyl adipate, diisostearyl adipate, dibutyl sebacate, diisocetyl sebacate, tributyl acetylcitrate, tributyl trimellitate, trioctyl trimellitate, trihexyl trimellitate, triolenyl trimellitate, and triisocetyl trimellitate.
Examples of esters of other acids with alcohols include: esters of unsaturated or branched fatty acids such as myristoleic acid, oleic acid, linoleic acid, linolenic acid, isopalmitic acid, and isostearic acid with alcohols such as ethylene glycol, propylene glycol, glycerol, trimethylolpropane, pentaerythritol, and sorbitan.
Examples of esters of mono-or polybasic acids with polyalkylene glycols include: polyethylene glycol dihexanoate, polyethylene glycol di-2-ethylhexanoate, polyethylene glycol dilaurate, polyethylene glycol dioleate, and diethylene glycol monomethyl adipate.
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, from the viewpoint of improving wettability. When the molecular weight is 250 or more, the heat resistance of the adhesive layer is good, and when the molecular weight is 1,000 or less, the wettability of the adhesive is good.
(solvent)
The adhesives of the invention may optionally contain more than one solvent. As the solvent, known ones can be used, and there can be mentioned: methyl ethyl ketone, ethyl acetate, toluene, xylene, acetone, and the like. From the viewpoints of solubility of the hydroxyl-terminated Urethane Prepolymer (UPH), boiling point of the solvent, and the like, ethyl acetate, toluene, and the like are particularly preferable.
(anti-deterioration agent)
The adhesive of the present invention may optionally contain more than one anti-deterioration agent. This can suppress deterioration of various properties due to long-term use of the adhesive layer. As the deterioration preventing agent, there can be mentioned: hydrolysis resistance agents, antioxidants, ultraviolet absorbers, light stabilizers, and the like.
< hydrolysis resistance agent >
In the case where a carboxyl group is generated by hydrolysis of the adhesive layer under a high-temperature and high-humidity environment, a hydrolysis resistant agent may be used to block the carboxyl group. As hydrolysis resistance agents, there can be mentioned: carbodiimide, isocyanate, oxazoline, and epoxy. Among them, a carbodiimide type is preferable from the viewpoint of the hydrolysis suppressing effect.
The carbodiimide-based hydrolysis inhibitor is a compound having one or more carbodiimide groups in one molecule.
Examples of the monocarbodiimide compound include: dicyclohexylcarbodiimide, diisopropylcarbodiimide, dimethylcarbodiimide, diisobutylcarbodiimide, dioctylcarbodiimide, diphenylcarbodiimide, naphthylcarbodiimide and the like.
The polycarbodiimide compound may be produced by subjecting a diisocyanate to a decarbonylation condensation reaction in the presence of a carbodiimidization catalyst. Examples of the diisocyanate include: 4, 4 ' -diphenylmethane diisocyanate, 3 ' -dimethoxy-4, 4 ' -diphenylmethane diisocyanate, 3 ' -dimethyl-4, 4 ' -diphenylmethane diisocyanate, 4 ' -diphenylether diisocyanate, 3 ' -dimethyl-4, 4 ' -diphenylether diisocyanate, 2, 4-tolylene diisocyanate, 2, 6-tolylene diisocyanate, 1-methoxyphenyl-2, 4-diisocyanate, isophorone diisocyanate, 4 ' -dicyclohexylmethane diisocyanate, tetramethylxylylene diisocyanate, and the like. Examples of the carbodiimidization catalyst include: and phospholene oxides such as 1-phenyl-2-phospholene-1-oxide, 3-methyl-2-phospholene-1-oxide, 1-ethyl-2-phospholene-1-oxide, and 3-phospholene isomers thereof.
Examples of the isocyanate hydrolysis inhibitor include: 2, 4-tolylene diisocyanate, 2, 6-tolylene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, 4 '-diphenylmethane diisocyanate, 2' -diphenylmethane diisocyanate, 3 '-dimethyl-4, 4' -biphenyl diisocyanate, 3 '-dimethoxy-4, 4' -biphenyl diisocyanate, 3 '-dichloro-4, 4' -biphenyl diisocyanate, 1, 5-naphthalene diisocyanate, 1, 5-tetrahydronaphthalene diisocyanate, tetramethylene diisocyanate, 1, 6-hexamethylene diisocyanate, dodecamethylene diisocyanate, trimethylhexamethylene diisocyanate, dimethylhexamethylene diisocyanate, dimethylnaphthalene diisocyanate, and mixtures thereof, 1, 3-cyclohexylene diisocyanate, 1, 4-cyclohexylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, hydrogenated xylylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, 4 ' -dicyclohexylmethane diisocyanate, 3 ' -dimethyl-4, 4 ' -dicyclohexylmethane diisocyanate, and the like.
Examples of the oxazoline hydrolysis inhibitor include: 2, 2 '-o-phenylbis (2-oxazoline), 2' -m-phenylbis (2-oxazoline), 2 '-p-phenylbis (4-methyl-2-oxazoline), 2' -m-phenylbis (4-methyl-2-oxazoline), 2 '-p-phenylbis (4, 4' -dimethyl-2-oxazoline), 2 '-m-phenylbis (4, 4' -dimethyl-2-oxazoline), 2 '-ethylidenebis (2-oxazoline), 2' -tetramethylenebis (2-oxazoline), 2 '-hexamethylenebis (2-oxazoline), 2' -octamethylenebis (2-oxazoline), 2, 2 '-ethylenebis (4-methyl-2-oxazoline), 2' -diphenylenebis (2-oxazoline), and the like.
Examples of the epoxy hydrolysis inhibitor include: diglycidyl ethers of aliphatic diols such as 1, 6-hexanediol, neopentyl glycol, and polyalkylene glycol; polyglycidyl ethers of aliphatic polyhydric alcohols such as sorbitol, sorbitan, polyglycerol, pentaerythritol, diglycerol, glycerol, and trimethylolpropane; polyglycidyl ethers of alicyclic polyols such as cyclohexanedimethanol; diglycidyl esters or polyglycidyl esters of aliphatic or aromatic polycarboxylic acids such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, trimellitic acid, adipic acid, and sebacic acid; diglycidyl ethers or polyglycidyl ethers of polyhydric phenols such as resorcinol, bis- (p-hydroxyphenyl) methane, 2, 2-bis- (p-hydroxyphenyl) propane, tris- (p-hydroxyphenyl) methane and 1, 1, 2, 2-tetrakis (p-hydroxyphenyl) ethane; n-glycidyl derivatives of amines such as N, N-diglycidylaniline, N-diglycidyltoluidine, and N, N' -tetraglycidyl-bis- (p-aminophenyl) methane; triglycidyl derivatives of aminophenols; triglycidyl tris (2-hydroxyethyl) isocyanurate and triglycidyl isocyanurate; epoxy resins such as o-cresol type epoxy resins and phenol novolac type epoxy resins.
The amount of the hydrolysis resistant agent to be added is not particularly limited, and is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 4.5 parts by mass, and particularly preferably 0.5 to 3 parts by mass, based on 100 parts by mass of the hydroxyl-terminated Urethane Prepolymer (UPH).
< antioxidant >
Examples of the antioxidant include a radical scavenger and a peroxide decomposer. Examples of the radical scavenger include phenol compounds and amine compounds. Examples of the peroxide decomposer include sulfur compounds and phosphorus compounds.
Examples of the phenolic compound include: 2, 6-di-tert-butyl-p-cresol, butylated hydroxyanisole, 2, 6-di-tert-butyl-4-ethylphenol, stearyl β - (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, 2 '-methylenebis (4-methyl-6-tert-butylphenol), 2' -methylenebis (4-ethyl-6-tert-butylphenol), 4 '-thiobis (3-methyl-6-tert-butylphenol), 4' -butylidenebis (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, 3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane, 1, 3, 5-trimethyl-2, 4, 6-tris (3, 5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis- [ methylene-3- (3 ', 5' -di-t-butyl-4 '-hydroxyphenyl) propionate ] methane, bis [3, 3' -bis- (4 '-hydroxy-3' -t-butylphenyl) butyrate ] diol ester, 1, 3, 5-tris (3 ', 5 ' -di-tert-butyl-4 ' -hydroxybenzyl) -S-triazine-2, 4, 6- (1H, 3H, 5H) trione, tocopherol, and the like.
Examples of the sulfur-based antioxidant include: dilauryl 3,3 ' -thiodipropionate, dimyristyl 3,3 ' -thiodipropionate, distearyl 3,3 ' -thiodipropionate, and the like.
Examples of the phosphorus-based compound include: triphenyl phosphite, diphenylisodecyl phosphite, 4' -butylidene-bis (3-methyl-6-tert-butylphenyl ditridecyl) phosphite, cycloneopentanetetraylbis (octadecyl phosphite), tris (nonylphenyl) phosphite, tris (monononylphenyl) phosphite, tris (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, phosphorus, Tris (2, 4-di-tert-butylphenyl) phosphite, cyclopentanetetraylbis (2, 6-di-tert-butyl-4-methylphenyl) phosphite, and octyl 2, 2-methylenebis (4, 6-di-tert-butylphenyl) phosphite.
Thermal degradation of the hydroxyl-terminated Urethane Prepolymer (UPH) is prevented by the use of an antioxidant. In addition, the bleed-out of the plasticizer (P) from the adhesive layer when the plasticizer (P) is used can be effectively suppressed.
The amount of the antioxidant to be added is not particularly limited, but is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 3 parts by mass, and particularly preferably 0.2 to 2 parts by mass, based on 100 parts by mass of the hydroxyl-terminated Urethane Prepolymer (UPH).
As the antioxidant, from the viewpoint of stability and antioxidant effect, it is preferable to use one or more phenol compounds as the radical scavenger, and more preferably to use one or more phenol compounds as the radical scavenger in combination with one or more phosphorus compounds as the peroxide decomposer. In addition, it is particularly preferable to use a phenol compound as a radical scavenger and a phosphorus compound as a peroxide decomposer in combination as the antioxidant, and to use these antioxidants and the hydrolysis resistance agent in combination.
< ultraviolet absorber >
Examples of the ultraviolet absorber include: benzophenone-based compounds, benzotriazole-based compounds, salicylic acid-based compounds, oxalanilide-based compounds, cyanoacrylate-based compounds, triazine-based compounds, and the like.
The amount of the ultraviolet absorber added is not particularly limited, but is preferably 0.01 to 3 parts by mass, more preferably 0.1 to 2.5 parts by mass, and particularly preferably 0.2 to 2 parts by mass, based on 100 parts by mass of the hydroxyl-terminated Urethane Prepolymer (UPH).
< light stabilizer >
Examples of the light stabilizer include hindered amine compounds and hindered piperidine compounds. The amount of the light stabilizer to be added is not particularly limited, but is preferably 0.01 to 2 parts by mass, more preferably 0.1 to 1.5 parts by mass, and particularly preferably 0.2 to 1 part by mass, based on 100 parts by mass of the hydroxyl-terminated Urethane Prepolymer (UPH).
(antistatic agent)
The adhesive of the present invention may optionally contain more than one antistatic agent (AS agent). Examples of the antistatic agent include inorganic salts, polyol compounds, ionic liquids, and surfactants, and among them, ionic liquids are preferable. The "ionic liquid" is also referred to as an ambient temperature molten salt, and is a salt having fluidity at 25 ℃.
Examples of the inorganic salt include: sodium chloride, potassium chloride, lithium perchlorate, ammonium chloride, potassium chlorate, aluminum chloride, copper chloride, ferrous chloride, ferric chloride, ammonium sulfate, potassium nitrate, sodium carbonate, sodium thiocyanate and the like.
Examples of the polyol compound include: propylene glycol, butylene glycol, hexylene glycol, polyethylene glycol, trimethylolpropane, pentaerythritol, and the like.
Examples of the ionic liquid containing an imidazolium ion include: 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide, 1, 3-dimethylimidazolium bis (trifluoromethylsulfonyl) imide, and 1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide.
Examples of the ionic liquid containing a pyridinium ion include: 1-methylpyridinium bis (trifluoromethylsulfonyl) imide, 1-butylpyridinium bis (trifluoromethylsulfonyl) imide, 1-hexylpyridinium bis (trifluoromethylsulfonyl) imide, 1-octylpyridinium bis (trifluoromethylsulfonyl) imide, 1-hexyl-4-methylpyridinium bis (trifluoromethylsulfonyl) imide, 1-hexyl-4-methylpyridinium hexafluorophosphate, 1-octyl-4-methylpyridinium bis (trifluoromethylsulfonyl) imide, 1-octyl-4-methylpyridinium bis (fluorosulfonyl) imide, 1-methylpyridinium bis (perfluoroethylsulfonyl) imide, and 1-methylpyridinium bis (perfluorobutylsulfonyl) imide, and the like.
Examples of the ionic liquid containing an ammonium ion include: trimethylheptylammonium bis (trifluoromethanesulfonyl) imide, N-diethyl-N-methyl-N-propylammonium bis (trifluoromethanesulfonyl) imide, N-diethyl-N-methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N-diethyl-N-methyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, tri-N-butylmethylammonium bis (trifluoromethanesulfonyl) imide, and the like.
Further, commercially available ionic liquids such as pyrrolizium salts, phosphonium salts, sulfonium salts, and the like can be suitably used.
Surfactants are classified into low-molecular surfactants and high-molecular surfactants. Either type is nonionic, anionic, cationic, and amphoteric.
Examples of the nonionic low-molecular-weight surfactant include: glycerin fatty acid ester, polyoxyalkylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene alkylamine fatty acid ester, fatty acid diethanolamide, and the like.
Examples of the anionic low-molecular-weight surfactant include: alkyl sulfonates, alkylbenzene sulfonates, alkyl phosphates, and the like.
Examples of the cationic low-molecular-weight surfactant include: tetraalkylammonium salts, trialkylbenzylammonium salts, and the like.
Examples of the amphoteric low-molecular-weight surfactant include alkyl betaines and alkyl imidazolium betaines.
Examples of the nonionic polymer surfactant include: polyether ester amide type, ethylene oxide-epichlorohydrin type, polyether ester type, and the like.
Examples of the anionic polymeric surfactant include polystyrene sulfonic acid type surfactants.
Examples of the cationic polymer surfactant include acrylate polymer type surfactants containing quaternary ammonium salt groups.
Examples of the amphoteric polymer surfactant include: and amino acid type amphoteric surfactants such as higher alkyl aminopropionates, and betaine type amphoteric surfactants such as higher alkyl dimethyl betaines and higher alkyl dihydroxyethyl betaines.
The amount of the antistatic agent added is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 5 parts by mass, per 100 parts by mass of the hydroxyl-terminated Urethane Prepolymer (UPH).
(leveling agent)
The adhesive of the present invention may optionally contain a leveling agent. By adding the leveling agent, the leveling property of the adhesive layer can be improved. The leveling agent includes an acrylic leveling agent, a fluorine leveling agent, a silicone leveling agent, and the like, and from the viewpoint of suppressing contamination of an adherend after re-peeling of the adhesive sheet, an acrylic leveling agent and the like are preferable.
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. When Mw is 500 or more, the amount of vaporization from the coating layer during heating and drying of the coating layer can sufficiently suppress contamination of the surroundings. When Mw is 20,000 or less, the leveling property of the adhesive layer is effectively improved.
The amount of the leveling agent is not particularly limited, and is preferably 0.001 to 2 parts by mass, more preferably 0.01 to 1.5 parts by mass, and particularly preferably 0.1 to 1 part by mass, based on 100 parts by mass of the hydroxyl-terminated Urethane Prepolymer (UPH), from the viewpoints of suppressing contamination of an adherend after re-peeling of the adhesive sheet and improving the leveling property of the adhesive layer.
(other optional ingredients)
The adhesive of the present invention may optionally contain other optional components within a range not impairing the effects of the present invention. As other optional components, there may be mentioned: a catalyst, a resin other than the urethane resin, a filler (talc, calcium carbonate, titanium oxide, or the like), a metal powder, a colorant (pigment, or the like), a foil, a softening agent, a conductive agent, a silane coupling agent, a lubricant, an anti-corrosion agent, a heat-resistant stabilizer, a weather-resistant stabilizer, a polymerization inhibitor, an antifoaming agent, or the like.
(mixing 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 required. The blending ratio of these is not particularly limited, and preferred blending ratios are as follows.
The amount of the one or more polyfunctional isocyanate compounds (I) is preferably 1 to 30 parts by mass, more preferably 3 to 20 parts by mass, per 100 parts by mass of the one or more hydroxyl-terminated Urethane Prepolymers (UPH). When the amount of the one or more polyfunctional isocyanate compounds (I) is 3 parts by mass or more, the cohesive force of the adhesive layer becomes good, and when it is 20 parts by mass or less, the pot life becomes good.
(method for producing adhesive)
The method for producing the adhesive of the present invention is not particularly limited.
The adhesive of the present invention can be produced by adding and mixing one or more polyfunctional isocyanate compounds (I) and optionally one or more optional components to the hydroxyl-terminated Urethane Prepolymer (UPH) synthesized by the above-described method (preferably, sequence 3).
[ adhesive sheet ]
The adhesive sheet of the present invention comprises a substrate sheet and an adhesive layer containing a cured product of the adhesive of the present invention. The adhesive layer may be formed on one or both sides of the substrate sheet. The exposed surface of the adhesive layer may be covered with a release sheet as necessary. Further, the release sheet may be peeled off when the adhesive sheet is attached to the adherend.
Fig. 1 is a schematic cross-sectional view of an adhesive sheet according to embodiment 1 of the present invention. In fig. 1, reference numeral 10 denotes an adhesive sheet, reference numeral 11 denotes a base sheet, reference numeral 12 denotes an adhesive layer, and reference numeral 13 denotes 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 is a schematic cross-sectional view of an adhesive sheet according to embodiment 2 of the present invention. In fig. 2, reference numeral 20 denotes an adhesive sheet, reference numeral 21 denotes a base sheet, reference numerals 22A and 22B denote adhesive layers, and reference numerals 23A and 23B denote release sheets.
The substrate sheet is not particularly limited, and examples thereof include a resin sheet, paper, and a metal foil. The substrate sheet may be a laminated sheet in which any one or more layers are laminated on at least one surface of these substrate sheets. The surface of the substrate sheet on the side on which the adhesive layer is formed may be subjected to an easy adhesion treatment such as corona discharge treatment and anchor coating agent (anchor coating agent) coating, if necessary.
The resin constituting the resin sheet is not particularly limited, and includes: ester resins such as Polyethylene Terephthalate (PET); olefin resins such as Polyethylene (PE) and Polypropylene (PP); vinyl resins such as polyvinyl chloride; amide resins such as nylon 66; urethane resin (including foam); combinations of these, and the like.
The thickness of the resin sheet other than the polyurethane sheet is not particularly limited, but is preferably 15 to 300 μm. The thickness of the polyurethane sheet (including the foam) is not particularly limited, and is preferably 20 μm to 50,000 μm.
The paper is not particularly limited, and includes: plain paper, coated paper, and the like.
The constituent metal of the metal foil is not particularly limited, and examples thereof include: aluminum, copper, combinations of these, and the like.
The release sheet is not particularly limited, and a known release sheet obtained by subjecting the surface of a substrate sheet such as a resin sheet or paper to a known release treatment such as coating with a release agent 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. The coating method may be any known method, and examples thereof include: roll coater method, comma coater method, die coater method, reverse coater method, screen printing method, gravure coater method, and the like.
Next, the coating layer is dried and cured to form an adhesive layer containing a cured product of the adhesive of the present invention. The heating and drying temperature is not particularly limited, but is preferably about 60 ℃ to 150 ℃. The thickness of the adhesive layer (thickness after drying) varies depending on the application, but is preferably 0.1 to 200 μm.
Next, if necessary, a release sheet is attached to the exposed surface of the adhesive layer by a known method.
In this manner, a single-sided adhesive sheet can be produced.
By performing the above operation on both sides, a double-sided adhesive sheet can be manufactured.
In contrast to the above method, the adhesive of the present invention may be applied to the surface of a release sheet to form a coating layer containing the adhesive of the present invention, the coating layer may be dried and cured to form an adhesive layer containing a cured product of the adhesive of the present invention, and a substrate sheet may be laminated on the exposed surface of the adhesive layer.
The method for producing an adhesive sheet preferably includes: a coating step of coating the adhesive on a substrate sheet; a heating step of forming an adhesive layer containing a cured product of an adhesive by heating and drying the formed coating layer; a winding step of winding the obtained adhesive sheet around a winding core to form an adhesive sheet roll; and a curing step of curing the adhesive sheet roller.
In the adhesive of the present invention, by using a relatively long-chain polyether polyol (HA) as the active hydrogen group-containing compound as a raw material of the hydroxyl-terminated Urethane Prepolymer (UPH), an adhesive layer having good wettability can be formed even with a formulation composition in which the amount of the plasticizer added is small/preferably no plasticizer is added.
In the present invention, by using the active hydrogen group-containing compound (HB) having a relatively short chain as the active hydrogen group-containing compound as the raw material of the hydroxyl-terminated Urethane Prepolymer (UPH), it is possible to improve the decrease in initial curability of the adhesive and the decrease in removability of the adhesive layer caused by the use of the polyether polyol (HA) having a relatively long chain.
The adhesive of the present invention can have a good pot life while having good initial hardenability. Since the pot life of the adhesive of the present invention is good, the viscosity of the adhesive does not become too high until the adhesive is applied to a substrate sheet, and uniform application of the adhesive can be achieved. The adhesive of the present invention has good initial curability, and therefore the coating layer or the adhesive layer is less susceptible to hot air during heating and drying of the coating layer or mechanical stress applied during winding and curing of the adhesive sheet obtained after heating and drying, and the occurrence of surface defects such as core marks, orange peel defects, and curling in the adhesive layer can be suppressed.
In the adhesive of the present invention, the addition of a plasticizer can be reduced or no plasticizer is used, and the active hydrogen group-containing compound (HB) having a relatively short chain is used as the active hydrogen group-containing compound as a raw material of the hydroxyl-terminated Urethane Prepolymer (UPH), whereby contamination of an adherend in which an adhesive component remains on the surface of the adherend after re-peeling of the adhesive sheet can be effectively suppressed particularly when the adhesive sheet is exposed to a high-temperature and high-humidity environment.
The adhesive of the present invention also has good adhesion to a substrate.
As described above, according to the present invention, it is possible to provide an adhesive agent which has a good pot life and initial curability, and which can form an adhesive layer having good wettability and substrate adhesiveness and good removability even when placed in a high-temperature and high-humidity environment, and an adhesive sheet using the same.
[ use ]
The adhesive sheet of the present invention can be used in the form of a tape, a label, a sheet, a double-sided tape, or the like. The adhesive sheet of the present invention can be preferably used as a surface protective sheet, a cosmetic sheet, an anti-slip sheet, and the like.
Flat panel displays such as Liquid Crystal Displays (LCDs) and organic electroluminescent displays (OELDs), and touch panel displays in which the flat panel displays and the touch panel are combined are widely used in electronic devices such as Televisions (TVs), Personal Computers (PCs), mobile phones, and portable information terminals.
The adhesive sheet of the present invention can be preferably used as a surface protective sheet for flat panel displays, touch panel displays (these are also referred to as simply "displays"), substrates produced or used in the production process of these (glass substrates, ITO/glass substrates having an Indium Tin Oxide (ITO) film formed on the glass substrate, and the like), optical members, and the like.
Examples
Synthetic examples, examples of the present invention, and comparative examples are described below. In the following description, "part" means part by mass, "%" means% by mass, and "RH" means relative humidity unless otherwise specified.
[ measurement of Mn and Mw ]
The number average molecular weight (Mn) and the weight average molecular weight (Mw) were measured by a Gel Permeation Chromatography (GPC) method. The measurement conditions are as follows. Both Mn and Mw are values in terms of polystyrene.
Measurement Condition
The device comprises the following steps: shimadzu excellence (Shimadzu project) (manufactured by Shimadzu corporation),
A pipe string; two TSKgel GMHs manufactured by Tosoh (TOSOH) are connected in series,
A detector: a differential refractive index detector (RID-10A),
Solvent: tetrahydrofuran (THF),
Flow rate: 1mL/min,
Temperature of the solvent: at 40 deg.C,
Sample concentration: 0.1 percent,
Sample injection amount: 100 μ L.
[ Material ]
The materials used are as follows.
< polyether polyol (HA) having a number average molecular weight (Mn) of 1650 or more per 1 functional group >
(HA-1): preminol 5001F (abbreviation: PREM 5001F in the table), a difunctional polyether polyol manufactured by Asahi glass company, Mn4000, hydroxyl number 2, hydroxyl number 28, degree of unsaturation 0.02, and,
(HA-2): preminol S4013F (abbreviation: PREM S4013F in the table), a difunctional polyether polyol manufactured by Asahi glass company, Mn12000, hydroxyl number 2, hydroxyl number 9, degree of unsaturation 0.007, a,
(HA-3): preminol S4318F (abbreviation: PREM S4318F in the table), a difunctional polyether polyol manufactured by Asahi glass company, Mn18000, hydroxyl number 2, hydroxyl number 6, degree of unsaturation 0.007, B,
(HA-4): aceclonol 828 (abbreviated as EXCE 828 in the table), trifunctional polyether polyol manufactured by Asahi glass company, Mn5000, hydroxyl number 3, hydroxyl number 34, degree of unsaturation 0.07, and,
(HA-5): preminol S3011 (abbreviation: PREM S3011 in the table), trifunctional polyether polyol manufactured by Asahi glass company, Mn10000, hydroxyl number 3, hydroxyl number 17, unsaturation degree 0.006, and,
(HA-6): preminol 3012 (abbreviation: PREM 3012 in the table), trifunctional polyether polyol manufactured by Asahi glass company, Mn12000, hydroxyl number 3, hydroxyl number 14, degree of unsaturation 0.020,
(HA-7): excenol 838 (abbreviation: EXCE 838 in the table), manufactured by Asahi glass company, a tetrafunctional polyether polyol, Mn8000, hydroxyl number 4, hydroxyl number 28, and unsaturation degree 0.07.
The units of unsaturation are meq/g.
The number of functional groups, Mn per 1 functional group and unsaturation degree of each polyether polyol (HA) were shown in Table 1 in advance.
< general polyether polyol (HM) having number-average molecular weight (Mn) of more than 300 and less than 1650 per 1 functional group >
(HM-1): PP-2000, a difunctional polyether polyol manufactured by Sanyo chemical Co., Ltd., Mn2000, a hydroxyl number of 2, a hydroxyl number of 56,
(HM-2): g-1500, a trifunctional polyether polyol manufactured by Adeka, Inc., Mn1500, hydroxyl number 3, hydroxyl value 112, a polyol obtained by esterification of a hydroxyl group in a polyol, a polyol obtained by esterification of a diol obtained by esterification of (ADEKA),
(HM-3): G-3000B, a trifunctional polyether polyol manufactured by Adeka, Inc., Mn3000, a hydroxyl number of 3, and a hydroxyl value of 56.
The number of functional groups of the respective polyether polyols (HM), Mn and Mn per 1 functional group are shown in Table 1 in advance.
< active Hydrogen group-containing Compound (HB) having a number-average molecular weight (Mn) of 300 or less per 1 functional group >
(HB-1): ethylene Glycol (EG), a compound containing only primary hydroxyl groups,
(HB-2): 1, 5-pentanediol, a monomer containing only primary hydroxyl groups,
(HB-3): 2-ethyl-1, 3-hexanediol (1, 3-octanediol), a polymer containing a primary hydroxyl group and a secondary hydroxyl group,
(HB-4): PPG600 (the same applies to PEG as the number indicates Mn), polypropylene glycol, a polymer produced by Sanyo chemical Co., Ltd., containing only a secondary hydroxyl group,
(HB-5): PEG300, polyethylene glycol, a compound containing only a primary hydroxyl group, a compound produced by Sanyo chemical Co., Ltd,
(HB-6): PEG600, polyethylene glycol, a compound containing only a primary hydroxyl group, manufactured by Sanyo chemical Co Ltd,
(HB-7): glycerol, a compound containing a primary hydroxyl group and a secondary hydroxyl group,
(HB-8): trimethylolpropane (TMP), a polymer containing only primary hydroxyl groups,
(HB-9): SP-750, a hexafunctional polyether polyol manufactured by Sanyo chemical Co., Ltd., Mn700, a hydroxyl number of 6, a hydroxyl group containing only secondary hydroxyl groups,
(HB-10): isophorone diamine.
The number of functional groups of each active hydrogen group-containing compound (HB), Mn, and Mn per 1 functional group are shown in Table 1 in advance.
< polyisocyanate (N) >
(N-1): isophorone diisocyanate (IPDI), manufactured by Tokyo chemical industries, Inc,
(N-2): hexamethylene Diisocyanate (HDI), manufactured by Tokyo chemical industries, Ltd,
(N-3): tolylene diisocyanate (a mixture of 2, 4-tolylene diisocyanate (80 mass%) and 2, 6-tolylene diisocyanate (20 mass%) (TDI), manufactured by Tosoh corporation.
The number of functional groups of each polyisocyanate (N), Mn and Mn per 1 functional group are shown in Table 1 in advance.
< polyfunctional isocyanate Compound (I) >
(I-1) Crohn-naphthalene (Coronate) HL, a Hexamethylene Diisocyanate (HDI)/Trimethylolpropane (TMP) adduct manufactured by Tosoh Corp,
(I-2) Sumido (Sumidur) N-3300, manufactured by Sumika Bayer Urethane, Hexamethylene Diisocyanate (HDI)/isocyanurate,
(I-3) Sumidu (Sumidur) N-75, manufactured by Sumika Bayer Urethane, Hexamethylene Diisocyanate (HDI)/biuret isocyanate (Isokyan biuret),
(I-4) Desmopur model Z4470BA, available from Sumika Bayer Urethane, isophorone diisocyanate (IPDI)/isocyanurate.
< antioxidant (C) >
(C-1): xylosus (IRGANOX)1135 (manufactured by BASF corporation).
< antistatic agent (AS agent) (E) >
(E-1): elekcel (Elexcel) AS-804 (manufactured by first Industrial pharmaceutical Co., Ltd.).
< plasticizer (P) >)
(P-1): ATBC (manufactured by mitsubishi chemical corporation), acetyl tributyl citrate.
[ Synthesis example of hydroxyl-terminated Urethane Prepolymer (UPH) ]
Synthesis example 1 (two-stage polymerization method)
100 parts by mass of polyether polyol (HA-1), 10 parts by mass of polyisocyanate (N-1), 47 parts by mass of toluene, and 0.01 part by mass of dioctyltin dilaurate as a catalyst were charged into a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet, a thermometer, and a dropping funnel, and mixed. The content liquid was slowly heated to 80 ℃ and reacted for 2 hours to obtain an isocyanate group-terminated urethane prepolymer (first-stage reaction). Then, the content liquid was cooled to 60 ℃ and 28 parts by mass of ethyl acetate was added, followed by reaction with 4 parts by mass of active hydrogen group-containing compound (HB-2) (second-stage reaction). In the whole of the reactions in the first and second stages, the ratio (NCO/H) of the number of moles of the isocyanate group (NCO) in the polyisocyanate (N) used in the reaction to the total number of moles of the active hydrogen groups (H) in all the active hydrogen group-containing compounds (HX) (in the above example, (HA-1) and (HB-1)) used in the reaction was 0.71.
After the disappearance of the remaining isocyanate groups was confirmed by Infrared spectroscopy (Infrared Radiation, IR) analysis), the content liquid was cooled and the reaction was terminated to obtain a colorless and transparent solution of a hydroxyl-terminated urethane prepolymer (UPA-1) having a viscosity of 2,100cps and a nonvolatile content of 60%. The obtained hydroxyl-terminated urethane prepolymer had Mn of 16,500 and Mw of 43,000.
The formulation composition, the ratio (NCO/H) of the number of moles of isocyanate groups (NCO) in the polyisocyanate (N) used in the reaction to the total number of moles of active hydrogen groups (H) in all the active hydrogen group-containing compounds (HX) used in the reaction, and the Mn and Mw of the obtained hydroxyl-terminated urethane prepolymer are shown in table 2-1. The unit of the amount of blending is "part by mass" (the same applies to other tables).
(Synthesis examples 2 to 42) (two-stage polymerization method)
In synthesis examples 2 to 42, colorless and transparent solutions of hydroxyl-terminated urethane prepolymer (UPA-2) to hydroxyl-terminated urethane prepolymer (UPA-42) were obtained by a two-stage polymerization method in the same manner as in synthesis example 1, except that the types of polyether polyol (HA), active hydrogen group-containing compound (HB), and polyisocyanate (N) used and the blending ratios thereof were changed.
In each synthesis example, the formulation composition, the ratio (NCO/H) of the number of moles of isocyanate groups (NCO) in the polyisocyanate (N) used in the reaction to the total number of moles of active hydrogen groups (H) in all the active hydrogen group-containing compounds (HX) used in the reaction, and the Mn and Mw of the obtained hydroxyl-terminated urethane prepolymer are shown in tables 2-1 to 2-5.
Synthesis example 43 (one-stage polymerization Process)
Into a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet, a thermometer, and a dropping funnel were charged 100 parts by mass of polyether polyol (HA-6), 4 parts by mass of active hydrogen group-containing compound (HB-2), 47 parts by mass of toluene, and 0.01 part by mass of dioctyltin dilaurate as a catalyst, and the mixture was mixed and slowly heated to 80 ℃. To the content liquid were added 9 parts by mass of polyisocyanate (N-1) and 28 parts by mass of ethyl acetate, and a reaction was carried out for 2 hours. The ratio (NCO/H) of the number of moles of isocyanate groups (NCO) in the polyisocyanate (N) used in the reaction to the total number of moles of active hydrogen groups (H) in all active hydrogen group-containing compounds (HX) (in the above example, (HA-6) and (HB-2)) used in the reaction was 0.58.
After disappearance of the remaining isocyanate group was confirmed by infrared spectroscopic analysis (IR analysis), the reaction was terminated by cooling the content liquid to obtain a white opaque solution of a hydroxy-terminated urethane prepolymer (UPA-43) having a viscosity of 3,300cps and a nonvolatile content of 60%. The obtained hydroxyl-terminated urethane prepolymer had Mn of 26,500 and Mw of 73,000.
The formulation composition, the ratio (NCO/H) of the number of moles of isocyanate groups (NCO) in the polyisocyanate (N) used in the reaction to the total number of moles of active hydrogen groups (H) in all the active hydrogen group-containing compounds (HX) used in the reaction, and the Mn and Mw of the obtained hydroxyl-terminated urethane prepolymer are shown in tables 2 to 5.
Synthesis examples C-1 to C-6 (one-stage polymerization method)
A colorless and transparent solution of the hydroxyl-terminated urethane prepolymer (UPB-1) to hydroxyl-terminated urethane prepolymer (UPB-6) for comparison was obtained by a one-stage polymerization method in the same manner as in Synthesis example 43 except that the kinds of the plurality of active hydrogen group-containing compounds (HX) selected from the group consisting of the polyether polyol (HA), the polyether polyol (HM) and the active hydrogen group-containing compound (HB), the kinds of the polyisocyanate (N) and the blending ratios thereof were changed in Synthesis examples C-1 to C-6.
In each synthesis example, the formulation composition, the ratio (NCO/H) of the number of moles of isocyanate groups (NCO) in the polyisocyanate (N) used in the reaction to the total number of moles of active hydrogen groups (H) in all the active hydrogen group-containing compounds (HX) used in the reaction, and Mn and Mw of the obtained hydroxyl-terminated urethane prepolymer are shown in tables 2 to 6.
Synthesis example C-7 (two-stage polymerization method)
A colorless and transparent solution of a hydroxyl-terminated urethane prepolymer (UPB-7) for comparison was obtained by a two-stage polymerization method in the same manner as in Synthesis example 1 except that in Synthesis example C-7, a polyether polyol (HM-3) was used in place of the polyether polyol (HA-1) and the kinds and raw material compounding ratios of the active hydrogen group-containing compound (HB) and the polyisocyanate (N) were changed.
The formulation composition, the ratio (NCO/H) of the number of moles of isocyanate groups (NCO) in the polyisocyanate (N) used in the reaction to the total number of moles of active hydrogen groups (H) in all the active hydrogen group-containing compounds (HX) used in the reaction, and the Mn and Mw of the obtained hydroxyl-terminated urethane prepolymer are shown in tables 2 to 6.
Preparation example D-1
In preparation example D-1, polyether polyol (HA-6), active hydrogen group-containing compound (HB-3), 47 parts by mass of toluene, 28 parts by mass of ethyl acetate and 0.01 part by mass of dioctyltin dilaurate as a catalyst were charged and mixed to obtain a colorless transparent solution of comparative polyol (PO-1) (polyol mixed solution). The formulation compositions are shown in tables 2 to 6.
[ production of urethane adhesive and adhesive sheet ]
(example 1)
A urethane adhesive was obtained by mixing 100 parts by mass of a solution of the hydroxyl-terminated urethane prepolymer (UPA-1) obtained in Synthesis example 1, 10 parts by mass of the polyfunctional isocyanate compound (I-1), 1 part by mass of the antioxidant (C-1) and 100 parts by mass of ethyl acetate as a solvent, and stirring the mixture with a disperser. The amounts of the respective materials other than the solvent used are expressed as nonvolatile components (the same applies to the other examples and comparative examples). The formulation composition is shown in Table 3-1. The pot life of the obtained adhesive was evaluated.
A50 μm-thick polyethylene terephthalate (PET) film (Lumiler T-60, manufactured by Toray corporation) was prepared as a substrate sheet. The obtained urethane adhesive was applied to one surface of the substrate sheet using a chipped wheel coater (registered trademark) so that the thickness after drying became 12 μm. Then, the formed coating layer was dried at 100 ℃ for two minutes to form a coherent layer. A release sheet (Super Stik) SP-PET38, manufactured by Lintec, Inc. was attached to the adhesive layer to a thickness of 38 μm to obtain an adhesive sheet. For the evaluation of initial hardenability, the curing was carried out for 3 hours under the conditions of 23 to 50% RH, and then the evaluation was carried out. For other evaluations, after one week of curing under conditions of 23 ℃ to 50% RH, evaluations were carried out.
(example 2 to example 55, comparative example 1 to comparative example 8)
In each of examples 2 to 55 and comparative examples 1 to 8, production of a urethane adhesive and an adhesive sheet and evaluation thereof were carried out in the same manner as in example 1 except that the kind and formulation ratio of the materials used were changed as shown in tables 3-1 to 3-2. In comparative example 8, an adhesive was produced by a single process.
[ evaluation items and evaluation methods ]
Evaluation items and evaluation methods of the adhesive and the adhesive sheet are as follows.
(pot life)
The obtained adhesive was put into a glass bottle with a cap immediately after the production, the glass bottle was put into a constant temperature water tank at 40 ℃, and the viscosity of the adhesive was measured 1 hour after and 6 hours after the start of the putting. The rate of increase in viscosity after 6 hours from that after 1 hour (viscosity after 6 hours/viscosity after 1 hour [ times ]) was determined. The evaluation criteria are as follows.
O: the viscosity increase rate was as good as 3 times lower.
And (delta): the viscosity increase rate is 3 to 5 times, and is practical.
X: the viscosity increase rate is over 5 times, and thus it is not practical.
[ initial hardenability ]
Test pieces having a width of 30mm and a length of 100mm were cut from the adhesive sheet after curing for 3 hours in an environment of 23 to 50% RH. The test piece was attached to a stainless steel (SUS) mesh (pore diameter: 0.077mm, wire diameter: 0.05mm), and then immersed in ethyl acetate. After extraction at 50 ℃ for 24 hours, the gel fraction (% by mass) was calculated based on the following formula (1) by drying at 100 ℃ for 30 minutes.
Gel fraction (% by mass) of (G2/G1) × 100 … (1)
In the formula, each symbol represents the following parameter.
G1: the quality of the adhesive layer before extraction was carried out with ethyl acetate,
g2: the quality of the adhesive layer after extraction with ethyl acetate and drying was used.
The evaluation criteria are as follows.
Very good: the gel fraction was 80 mass% or more, and the gel fraction was excellent.
O: the gel fraction was preferably 50 mass% or more and less than 80 mass%.
And (delta): the gel fraction is 20 mass% or more and less than 50 mass%, and is practically usable.
X: gel fraction was less than 20 mass%, and it was not practical.
(wettability)
A test piece having a width of 50mm and a length of 100mm was cut from the adhesive sheet after being cured for one week in an environment of 23 to 50% RH, and the release sheet was peeled from the test piece after being left to stand in an environment of 23 to 50% RH for 30 minutes. One end of the test piece from which the release sheet was peeled in the longitudinal direction was fixed to the end of the glass plate, and the other end, which was not fixed, was lifted up by hand from the surface of the glass plate to a position of 5cm in height. In this state, the hand was released, and the time until the entire adhesive layer was in close contact with the surface of the glass plate was measured. The evaluation criteria are as follows.
O: it was good when the time was less than 4 seconds until the sealing.
And (delta): it is practical for 4 seconds or more and less than 8 seconds until the sealing.
X: it is not practical until the sealing is carried out for 8 seconds or more.
(substrate adhesion)
The adhesive layer of the adhesive sheet after curing for one week in an environment of 23 to 50% RH was half-cut 11 times at 1mm intervals in each of two linear directions perpendicular to each other, thereby forming 100 pieces of 1mm square. After rubbing the 100 pieces of the base material sheet with a finger for 1 minute, the number of pieces remaining on the base material sheet was visually counted. The evaluation criteria are as follows.
Very good: the number of remaining blocks is 81 to 100, which is excellent.
O: the number of remaining blocks was 61 to 80, which was good.
And (delta): the number of remaining blocks is 41 to 60, and this is practical.
X: the number of remaining blocks is 0 to 40, which is not practical.
(removability)
Three test pieces having a width of 70mm and a length of 100mm were cut from the adhesive sheet after being cured for one week in an environment of 23 to 50% RH. For the three test pieces, the release sheet was peeled off in an environment of 23 to 50% RH, and a sodium hydroxide glass plate was attached to the surface of the exposed adhesive layer, followed by pressure bonding using a laminator. The three laminates obtained were placed in an oven set at 85 to 85% RH for 72 hours (condition 1), 120 hours (condition 2), and 240 hours (condition 3), respectively. The three laminates were taken out from the oven, air-cooled in an environment of 23 to 50% RH for 3 hours, and then the adhesive sheets were peeled from the glass plate, and the removability was evaluated by visual observation. The evaluation criteria are as follows.
Very good: under all conditions, no adhesive layer component was attached to the glass surface, and the adhesion was excellent.
O: in condition 1 and condition 2, no adhesive layer component was adhered to the glass surface at all, but in condition 3, the adhesive layer component was adhered to the glass surface, which was good.
And (delta): in condition 1, no adhesive layer component was attached to the glass surface at all, but in condition 2 and condition 3, adhesive layer component was attached to the glass surface, and it was found to be practical.
X: under all conditions, the adhesion layer-generating components adhere to the glass surface and are not practical.
(contamination by adherend)
A test piece having a width of 70mm and a length of 100mm was cut from the adhesive sheet after being cured for one week in an environment of 23 to 50% RH, and the release sheet was peeled off in an environment of 23 to 50% RH. The sodium hydroxide glass plate was attached to the surface of the exposed adhesive layer, and pressure-bonded by a laminator. The obtained laminate was placed in an oven set at 85-85% RH for 72 hours. The laminate was taken out from the oven, air-cooled in an environment of 23 to 50% RH for 3 hours, and then the adhesive sheet was peeled off from the glass plate, and contamination by an adherend was evaluated. In a dark room, the surface of the glass plate on the side to which the adhesive sheet is attached was irradiated with a Light Emitting Diode (LED) lamp and evaluated by visual observation. The evaluation criteria are as follows.
Very good: the adhesion of the adhesive layer component was not observed at all on the glass surface, and the adhesion was excellent.
O: the adhesion of the thin adhesive layer component was observed at 1 to 2 sites on the glass surface, and was good.
And (delta): adhesion of a thin adhesive layer component was observed at 3 portions of the glass surface, and it was found to be practical.
X: adhesion of a thin adhesive layer component was observed at 4 or more sites on the glass surface and/or adhesion of a thick adhesive layer component was observed at 1 to 2 sites on the glass surface, which was not practical.
[ evaluation results ]
The evaluation results are shown in tables 4-1 to 4-2.
In examples 1 to 55, a urethane adhesive containing a hydroxyl-terminated Urethane Prepolymer (UPH) which is a reaction product of a relatively long-chain polyether polyol (HA) having a number average molecular weight (Mn) of 1650 or more per 1 functional group, a relatively short-chain active hydrogen group-containing compound (HB) having a number average molecular weight (Mn) of 300 or less per 1 functional group, and a polyisocyanate (N) and a polyfunctional isocyanate compound (I) was produced.
In all of these examples, an adhesive having good pot life and initial curability was produced, and an adhesive sheet having good wettability, good substrate adhesion, and good removability and adherend contamination suppression even when exposed to a high-temperature and high-humidity environment could be produced without adding a plasticizer or reducing the addition of a plasticizer.
In comparative example 2 using a hydroxyl-terminated urethane prepolymer obtained using only a plurality of general-purpose polyether polyols (HM) having number-average molecular weights (Mn) of more than 300 and less than 1650 per 1 functional group as the active hydrogen group-containing compound, the wettability of the obtained adhesive sheet was poor because no plasticizer was added.
In comparative examples 1, 3 to 5 using a hydroxyl-terminated urethane prepolymer obtained by using, as the active hydrogen group-containing compound (HX), a polyether polyol (HA) having a relatively long chain with a number average molecular weight (Mn) of 1650 or more per 1 functional group and a general-purpose polyether polyol (HM) having a number average molecular weight (Mn) of more than 300 and less than 1650 per 1 functional group, adhesive sheets having good wettability can be produced without adding a plasticizer. However, in these comparative examples, since the active hydrogen group-containing compound (HB) having a relatively short chain with a number average molecular weight (Mn) of 300 or less per 1 functional group is not used as a raw material of the hydroxyl-terminated urethane prepolymer, the pot life and initial curability of the adhesive are poor, and the removability and adherend contamination suppression of the adhesive sheet are poor. The adhesive sheets obtained in these comparative examples also had poor adhesion to the substrate.
In comparative examples 6 and 7 using a hydroxyl-terminated urethane prepolymer obtained by using, as the active hydrogen group-containing compound (HX), a general-purpose polyether polyol (HM) having a number average molecular weight (Mn) per 1 functional group of more than 300 and less than 1650, and a relatively short-chain active hydrogen group-containing compound (HB) having a number average molecular weight (Mn) per 1 functional group of 300 or less, a relatively long-chain polyether polyol (HA) having a number average molecular weight (Mn) per 1 functional group of 1650 or more is not used without adding a plasticizer, and thus the wettability of the adhesive sheet obtained is poor. In comparative example 6, the terminal hydroxyl groups of the urethane prepolymer obtained by the one-stage polymerization method were present in a mixture of primary and secondary, and therefore the initial curing properties of the obtained adhesive were also poor. In comparative example 7, the terminal hydroxyl group of the urethane prepolymer obtained by the two-stage polymerization method was only one stage, and thus the initial curability was improved.
In comparative example 8, a urethane adhesive was produced by a single process by mixing a relatively long-chain polyether polyol (HA) having a number average molecular weight (Mn) per 1 functional group of 1650 or more, a relatively short-chain active hydrogen group-containing compound (HB) having a number average molecular weight (Mn) per 1 functional group of 300 or less, and a polyfunctional isocyanate compound (I) without using a hydroxyl-terminated Urethane Prepolymer (UPH). The obtained adhesive has poor initial curability, and the adhesive sheet using the adhesive has poor removability and adherend contamination suppression.
[ Table 1]
Figure BDA0002210957440000231
Figure BDA0002210957440000241
Figure BDA0002210957440000251
Figure BDA0002210957440000261
Figure BDA0002210957440000271
[ tables 2 to 5]
Figure BDA0002210957440000281
Figure BDA0002210957440000291
Figure BDA0002210957440000301
Figure BDA0002210957440000311
Figure BDA0002210957440000321
Figure BDA0002210957440000331
The present invention is not limited to the above-described embodiments and examples, and design changes can be made as appropriate without departing from the spirit of the present invention.
The present application claims priority based on japanese patent application No. 2018-077040 filed on 12.4.4.2018, the disclosure of which is incorporated in its entirety into the present specification.
Description of the symbols
10. 20: adhesive sheet
11. 21: substrate sheet
12. 22A, 22B: adhesive layer
13. 23A, 23B: release sheet

Claims (10)

1. An adhesive, comprising:
a hydroxyl-terminated Urethane Prepolymer (UPH) which is a reaction product of a plurality of active hydrogen group-containing compounds (HX) including a polyether polyol (HA) having a number average molecular weight of 2000 or more per 1 functional group and an active hydrogen group-containing compound (HB) having a number average molecular weight of 30 to 100 per 1 functional group and having a plurality of active hydrogen groups in one molecule, and one or more polyisocyanates (N); and
a polyfunctional isocyanate compound (I), and
the active hydrogen group-containing compound (HB) includes an active hydrogen group-containing compound containing only a primary hydroxyl group as an active hydrogen group,
the amount of the active hydrogen group-containing compound (HB) is 1.0 to 20 parts by mass per 100 parts by mass of the polyether polyol (HA).
2. The adhesive according to claim 1, wherein a ratio (NCO/H) of the number of moles of isocyanate groups (NCO) of the polyisocyanate (N) to the total number of moles of active hydrogen groups (H) of the one or more active hydrogen group-containing compounds (HX) is 0.20 to 0.84.
3. The adhesive according to claim 1 or 2, wherein the one or more polyether polyols (HA) comprise trifunctional or higher polyether polyols.
4. The adhesive according to claim 1 or 2, wherein the plasticizer is added in an amount (P) of 0 to 10 parts by mass with respect to 100 parts by mass of the hydroxyl-terminated Urethane Prepolymer (UPH).
5. The adhesive according to claim 1 or 2, wherein the hydroxyl-terminal Urethane Prepolymer (UPH) is a reaction product of an isocyanate-terminal Urethane Prepolymer (UPN) which is a reaction product of a polyether polyol (HA) and a polyisocyanate (N), and an active hydrogen group-containing compound (HB).
6. The adhesive according to claim 1 or 2, wherein the one or more polyisocyanates (N) comprise isophorone diisocyanate.
7. The adhesive according to claim 1 or 2, further comprising one or more deterioration preventing agents selected from the group consisting of an antioxidant, a hydrolysis resistance agent, an ultraviolet absorber, and a light stabilizer.
8. The adhesive of claim 1 or 2, further comprising an antistatic agent.
9. An adhesive sheet comprising a substrate sheet and an adhesive layer comprising a cured product of the adhesive according to any one of claims 1 to 8.
10. A method for producing a hydroxyl-terminated urethane prepolymer, comprising:
a step of reacting one or more polyether polyols (HA) having an average molecular weight of 2000 or more per 1 functional group with one or more polyisocyanates (N) at an excess isocyanate group ratio to produce an isocyanate group-terminated Urethane Prepolymer (UPN); and
reacting the isocyanate group-terminated Urethane Prepolymer (UPN) with one or more active hydrogen group-containing compounds (HB) having an average molecular weight of 30 to 100 per 1 functional group and having a plurality of active hydrogen groups in one molecule, and
the active hydrogen group-containing compound (HB) includes an active hydrogen group-containing compound containing only a primary hydroxyl group as an active hydrogen group,
the amount of the active hydrogen group-containing compound (HB) is 1.0 to 20 parts by mass per 100 parts by mass of the polyether polyol (HA).
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Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7457464B2 (en) * 2019-06-27 2024-03-28 ヘンケルジャパン株式会社 adhesive for lamination
JP7469611B2 (en) 2020-02-27 2024-04-17 東ソー株式会社 Urethane prepolymer composition
JP6904455B1 (en) * 2020-03-27 2021-07-14 横浜ゴム株式会社 Two-component curable adhesive composition
JP6866957B1 (en) * 2020-10-27 2021-04-28 東洋インキＳｃホールディングス株式会社 Adhesive for skin application, cured product and adhesive tape for skin application

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006096785A (en) * 2004-09-28 2006-04-13 Aica Kogyo Co Ltd Urethane resin-based adhesive composition and bonding method
JP2006140348A (en) * 2004-11-12 2006-06-01 Lintec Corp Marking method and sheet used both for protective film formation and for dicing
JP2007238766A (en) * 2006-03-08 2007-09-20 Mitsubishi Chemicals Corp Adhesive, method for producing the same, adhesive cured product and laminate using the cured product
CN101052663A (en) * 2004-09-30 2007-10-10 旭硝子株式会社 Method for producing urethane resin and pressure sensitive adhesive
JP2007277484A (en) * 2006-04-11 2007-10-25 Nitto Denko Corp Pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and surface-protective film
TW200815491A (en) * 2006-08-04 2008-04-01 Hitachi Kasei Polymer Co Ltd Urethane (meth)acrylate oligomer and sheet using the same
CN103492511A (en) * 2011-04-22 2014-01-01 日东电工株式会社 Surface-protecting film
CN102858898B (en) * 2010-03-31 2014-10-08 琳得科株式会社 Adhesive sheet
CN104263310A (en) * 2014-09-19 2015-01-07 周建明 Single-component moisture-curing polyurethane adhesive and preparation method thereof
CN104877614A (en) * 2015-06-11 2015-09-02 北京高盟新材料股份有限公司 Bicomponent polyether type composite adhesive quickly cured at room temperature and preparation method of bicomponent polyether type composite adhesive
JP2016204468A (en) * 2015-04-17 2016-12-08 東ソー株式会社 Urethane prepolymer, and two-liquid type urethane adhesive using the same
JP2017008314A (en) * 2015-06-24 2017-01-12 東洋インキＳｃホールディングス株式会社 Adhesive and adhesive sheet
JP2017210511A (en) * 2016-05-24 2017-11-30 東洋インキＳｃホールディングス株式会社 Pressure-sensitive adhesive, adhesive film and optical laminate
JP2018002954A (en) * 2016-07-07 2018-01-11 東ソー株式会社 Urethane formative composition, and urethane adhesive using the same
WO2018020803A1 (en) * 2016-07-29 2018-02-01 東洋インキＳｃホールディングス株式会社 Adhesive agent and adhesive sheet

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105646817B (en) * 2010-04-14 2019-08-13 三菱化学株式会社 Polycarbonate glycol and preparation method thereof, and used its polyurethane and active energy ray-curable polymer composition
WO2014010524A1 (en) * 2012-07-11 2014-01-16 タツタ電線株式会社 Curable electroconductive adhesive composition, electromagnetic shielding film, electroconductive adhesive film, adhesion method, and circuit board
CN104768990B (en) * 2013-11-07 2017-08-08 Sika技术股份公司 The reactive fluid rubber being made up of the isocyanate-terminated prepolymer closed with glycol capturing agent
EP3239261B1 (en) * 2014-12-24 2023-11-29 Toyo Ink Sc Holdings Co., Ltd. Method for producing an adhesive composition and a laminate
JP2016138237A (en) 2015-01-22 2016-08-04 旭硝子株式会社 Polyol composition for pressure-sensitive adhesive, kit for pressure-sensitive adhesive, and laminate

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006096785A (en) * 2004-09-28 2006-04-13 Aica Kogyo Co Ltd Urethane resin-based adhesive composition and bonding method
CN101052663A (en) * 2004-09-30 2007-10-10 旭硝子株式会社 Method for producing urethane resin and pressure sensitive adhesive
JP2006140348A (en) * 2004-11-12 2006-06-01 Lintec Corp Marking method and sheet used both for protective film formation and for dicing
JP2007238766A (en) * 2006-03-08 2007-09-20 Mitsubishi Chemicals Corp Adhesive, method for producing the same, adhesive cured product and laminate using the cured product
JP2007277484A (en) * 2006-04-11 2007-10-25 Nitto Denko Corp Pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and surface-protective film
TW200815491A (en) * 2006-08-04 2008-04-01 Hitachi Kasei Polymer Co Ltd Urethane (meth)acrylate oligomer and sheet using the same
CN102858898B (en) * 2010-03-31 2014-10-08 琳得科株式会社 Adhesive sheet
CN103492511A (en) * 2011-04-22 2014-01-01 日东电工株式会社 Surface-protecting film
CN104263310A (en) * 2014-09-19 2015-01-07 周建明 Single-component moisture-curing polyurethane adhesive and preparation method thereof
JP2016204468A (en) * 2015-04-17 2016-12-08 東ソー株式会社 Urethane prepolymer, and two-liquid type urethane adhesive using the same
CN104877614A (en) * 2015-06-11 2015-09-02 北京高盟新材料股份有限公司 Bicomponent polyether type composite adhesive quickly cured at room temperature and preparation method of bicomponent polyether type composite adhesive
JP2017008314A (en) * 2015-06-24 2017-01-12 東洋インキＳｃホールディングス株式会社 Adhesive and adhesive sheet
JP2017210511A (en) * 2016-05-24 2017-11-30 東洋インキＳｃホールディングス株式会社 Pressure-sensitive adhesive, adhesive film and optical laminate
JP2018002954A (en) * 2016-07-07 2018-01-11 東ソー株式会社 Urethane formative composition, and urethane adhesive using the same
WO2018020803A1 (en) * 2016-07-29 2018-02-01 東洋インキＳｃホールディングス株式会社 Adhesive agent and adhesive sheet

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
HMDI型透明聚氨酯弹性体合成工艺研究;滕业方;《化工新型材料》;20151215;第43卷(第12期);第163-43页 *
聚氨酯胶粘剂固化反应对其流变性能的影响;孙晓微等;《高分子材料科学与工程》;20130315;第29卷(第03期);第31-34页 *

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