WO2022107689A1

WO2022107689A1 - Polyisocyanate compositions, cured film, coating film, pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and resin composition

Info

Publication number: WO2022107689A1
Application number: PCT/JP2021/041684
Authority: WO
Inventors: 昌嗣東; 麗武井
Original assignee: 旭化成株式会社
Priority date: 2020-11-19
Filing date: 2021-11-12
Publication date: 2022-05-27
Also published as: TW202225242A; TW202313749A; CN116368006A; KR20230059817A; TWI836292B

Abstract

The present invention provides a polyisocyanate composition derived from at least one diisocyanate selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, a bifunctional polyol (A1) having a number-average molecular weight of 1,500 or higher, and a tri- or higher-functional polyol (B1) having a number-average molecular weight of 500 or higher, the molar ratio of the isocyanate groups of the diisocyanate to the hydroxyl groups of the polyol (A1) and polyol (B1) being 2-30, the polyisocyanate composition having a weight-average molecular weight of 1,400 or higher. Also provided is a polyisocyanate composition derived from at least one diisocyanate selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, a polycaprolactone polyol (A2), and a polyether polyol (B2), the polyisocyanate composition containing poly(propylene glycol) in an amount of 20 parts by mass or more per 100 parts by mass of the polyether polyol (B2).

Description

Polyisocyanate composition, cured film, coating film, pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet and resin composition

The present invention relates to a polyisocyanate composition, a cured film, a coating film, an adhesive composition and an adhesive sheet. The present invention also relates to polyisocyanate compositions and resin compositions.

In recent years, plastic films, adhesives, and adhesives have been used in various fields because they have a wide range of functions. Under such circumstances, the application is increasing not only to flat plate-shaped parts but also to parts that have not been used frequently, such as curved surfaces and parts with bending movements. For example, flexible displays and foldable displays are mentioned, and the demand for them has been increasing rapidly in recent years. Along with this, there is a demand for highly flexible films, adhesives, and adhesives that have good followability to curved surfaces and bending and have excellent bending resistance.

In addition, regarding curable polyurethane, in order to achieve coating film physical properties that cannot be solved by conventional curing agents, higher quality and higher performance of curing agents are increasing as market needs. In particular, in coating films, pressure-sensitive adhesives, adhesives, sealings, etc. that develop final physical properties by curing, further development is required because the performance derived from the curing agent greatly contributes. In particular, as a market trend, there is a tendency that high flexibility of the cured composition is required.

Patent Documents 1 and 2 disclose a polyisocyanate composition modified with a polyester polyol or a polyether polyol. It is disclosed that the coating film formed by blending the composition is excellent in extensibility and bending resistance.

Japanese Unexamined Patent Publication No. 61-28518 Japanese Unexamined Patent Publication No. 2-1718

There is a demand for a polyisocyanate composition having higher flexibility than the polyisocyanate compositions described in Patent Documents 1 and 2. Further, in Patent Documents 1 and 2, no specific study has been made on the use of adhesives and adhesives.

The present invention has been made in view of the above circumstances, and has good flexibility of a cured film obtained by curing a polyisocyanate composition alone, and has good adhesiveness, cohesive force, curability and transparency. Provided is a polyisocyanate composition which can obtain an excellent pressure-sensitive adhesive sheet. Further, the present invention provides a cured film, a coating film, a pressure-sensitive adhesive composition and a pressure-sensitive adhesive sheet using the polyisocyanate composition.

Further, there is a need for a polyisocyanate composition that can obtain a coating film that is more flexible than the polyisocyanate compositions described in Patent Documents 1 and 2 in a harsh environment, specifically at a low temperature of about −10 ° C. Has been done.

The present invention has been made in view of the above circumstances, has good compatibility with the main agent in a low temperature environment of about -10 ° C, and has a low temperature of about -10 ° C and 23 when used as a coating film. Provided is a polyisocyanate composition having excellent flexibility at room temperature of about ° C. Further, a resin composition using the polyisocyanate composition is provided.

That is, the present invention includes the following aspects.
(1) At least one diisocyanate selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, a bifunctional polyol (A1) having a number average molecular weight of 1500 or more, and a number average molecular weight of 500 or more 3 A polyisocyanate composition derived from a functional or higher polyol (B1).
The molar ratio of the isocyanate group of the diisocyanate to the hydroxyl groups of the polyol (A1) and the polyol (B1) is 2 or more and 30 or less.
A polyisocyanate composition having a weight average molecular weight of 1400 or more.
(2) The mass ratio of the polyol (B1) to the polyol (A1) is 0.1 / 99.9 or more and 99.9 / 0.1 or less, and
With respect to 100 parts by mass of the diisocyanate
The content of the polyol (A1) is 0.1 parts by mass or more and 250 parts by mass or less.
The polyisocyanate composition according to (1), wherein the content of the polyol (B1) is 1 part by mass or more and 190 parts by mass or less.
(3) The polyisocyanate composition according to (1) or (2), wherein the polyisocyanate composition has an average number of isocyanate functional groups of 2 or more and 6 or less.
(4) The polyisocyanate composition according to any one of (1) to (3), wherein the polyisocyanate composition has an isocyanate group content of 1% by mass or more and 10% by mass or less.
(5) The polyol (A1) and the polyol (B1) are at least one polyol selected from the group consisting of polyester polyols, polyether polyols, epoxy polyols, polyolefin polyols, and polycarbonate polyols, (1) to (1). The polyisocyanate composition according to any one of 4).
(6) The polyisocyanate composition according to any one of (1) to (5), wherein the polyol (A1) and the polyol (B1) are polyester polyols.
(7) The polyisocyanate composition according to (6), wherein the polyol (A1) and the polyol (B1) are polycaprolactone polyols.
(8) The polyisocyanate composition according to any one of (1) to (7) is applied onto glass, stored at 23 ° C. in a 65% humidity environment for 168 hours, and then stored at 50 ° C. for 24 hours. A cured film having a film thickness of 40 μm formed after heating for a long time.
A cured film having a König hardness of 60 times or less in an environment of 23 ° C.
(9) The polyisocyanate composition according to any one of (1) to (7), the glass transition temperature is 29.1 ° C., the hydroxyl value is 139 mgKOH / g, and the weight average molecular weight is 2. A coating composition containing an acrylic polyol having a thickness of .56 × 10 ⁴ was cured at 90 ° C. for 30 minutes and stored at 23 ° C. in a 65% humidity environment for 168 hours to obtain a coating film having a thickness of 40 μm.
The test piece having a width of 10 mm and a length of 100 mm of the coating film was set in a tensile tester so that the gripping tool distance was 20 mm, and the elongation rate in the tensile test measured at a speed of 20 mm / min was 50% or more. Moreover, the coating film has a stress of 28 MPa or less when the elongation rate is 140%.
(10) A pressure-sensitive adhesive composition comprising the polyisocyanate composition according to any one of (1) to (7) and a crosslinkable functional group-containing polymer having a glass transition temperature of 0 ° C. or lower.
(11) The pressure-sensitive adhesive composition according to (10), wherein the crosslinkable functional group-containing polymer is an acrylic polymer.
(12) Substrate and
A pressure-sensitive adhesive layer is provided on the substrate.
A pressure-sensitive adhesive sheet in which the pressure-sensitive adhesive layer is made of a cured product of the pressure-sensitive adhesive composition according to (10) or (11).
(13) The pressure-sensitive adhesive sheet according to (12), wherein the pressure-sensitive adhesive layer has a thickness of 1 μm or more and 1000 μm or less.
(14) A pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer having a thickness of 50 μm, which is obtained by applying the pressure-sensitive adhesive composition on a peel-treated polyethylene terephthalate film having a thickness of 38 μm, drying at 130 ° C. for 3 minutes, and curing the pressure-sensitive adhesive composition, 23. Gel fraction calculated by wrapping in a mesh sheet after storage in a 50% RH environment for 7 days, immersing in ethyl acetate at 23 ° C for 1 week, taking out, and drying at 120 ° C for 2 hours. The pressure-sensitive adhesive sheet according to (12) or (13), wherein is 20% by mass or more and 99% by mass or less.
(15) Adhesive having a width of 20 mm and a length of 100 mm, comprising a pressure-sensitive adhesive layer having a thickness of 50 μm, which is obtained by applying the pressure-sensitive adhesive composition on a polyethylene terephthalate film having a thickness of 25 μm, drying at 130 ° C. for 3 minutes, and curing the pressure-sensitive adhesive composition. The sheet was stored in a 23 ° C., 50% RH environment for 7 days, then crimped once with a 2 kg roller using a SUS304BA steel plate as an adherend, cured at 23 ° C. for 30 minutes, and then 23 ° C., 300 mm / min. The pressure-sensitive adhesive sheet according to any one of (12) to (14), wherein the 180-degree peel adhesive strength measured at a speed is 0.05 N / 20 mm or more and 55 N / 20 mm or less.
(16) The pressure-sensitive adhesive layer having a thickness of 50 μm, which was obtained by applying the pressure-sensitive adhesive composition on a polyethylene terephthalate film having a thickness of 38 μm and drying and curing at 130 ° C. for 3 minutes, was peeled off. After peeling from the polyethylene terephthalate film, the haze value measured by the haze meter of the adhesive sheet bonded on the glass having the haze value of 0.1% is 2% or less, (12) to (15). Adhesive sheet described in any one.
(17) The polyisocyanate composition according to any one of (1) to (7), a glass transition temperature of 0 ° C. or higher and 100 ° C. or lower, a hydroxyl value of 10 mgKOH / g or higher and 400 mgKOH / g or lower, and A resin composition containing an acrylic polyol having a weight average molecular weight of 5.00 × 10 ³ or more and 1.0 × ¹⁰⁵ or less is cured at 90 ° C. for 30 minutes and stored at 23 ° C. for 168 hours in a 65% humidity environment. After that, it is a resin film with a thickness of 40 μm.
A test piece having a width of 10 mm and a length of 100 mm of the resin film is set in a tensile tester so that the grip distance is 20 mm, and the breaking point stress in the tensile test measured at a speed of 20 mm / min is 2.0 MPa or more. There are coatings, films and adhesive compositions.
(18) The polyisocyanate composition according to any one of (1) to (7), a glass transition temperature of 0 ° C. or higher and 100 ° C. or lower, a hydroxyl value of 10 mgKOH / g or higher and 400 mgKOH / g or lower, and A resin composition containing an acrylic polyol having a weight average molecular weight of 5.00 × 10 ³ or more and 1.0 × ¹⁰⁵ or less is cured at 90 ° C. for 30 minutes and stored at 23 ° C. for 168 hours in a 65% humidity environment. After that, it is a resin film with a thickness of 40 μm.
A test piece having a width of 10 mm and a length of 100 mm of the resin film was set in a tensile tester so as to have a gripping tool distance of 20 mm, and fracture to 140% elongation stress in a tensile test measured at a speed of 20 mm / min. A coating film, a film and an adhesive composition having a point stress of 1.1 or more.
(19) Derived from at least one diisocyanate selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, and polycaprolactone polyols (A2) and polyether polyols (B2).
A polyisocyanate composition containing 20 parts by mass or more of polypropylene glycol with respect to 100 parts by mass of the polyether polyol (B2).
(20) The number average molecular weight of the polycaprolactone polyol (A2) is 500 or more and 1500 or less, and
The polyisocyanate composition according to (19), wherein the polyether polyol (B2) has a number average molecular weight of 1000 or more and 7000 or less.
(21) The polyisocyanate composition according to (20), wherein the weight ratio of the polytetramethylene ether glycol to the polypropylene glycol in the polyether polyol (B2) is 0/100 or more and 60/40 or less.
(22) One of (19) to (21), wherein the molar ratio of the isocyanate group of the diisocyanate to the hydroxyl groups of the polycaprolactone polyol (A2) and the polyether polyol (B2) is 2 or more and 10 or less. The polyisocyanate composition described.
(23) The polyisocyanate according to any one of (19) to (22), wherein the mass ratio of the polycaprolactone polyol (A2) to the polyether polyol (B2) is 10/90 or more and 90/10 or less. Composition.
(24) A resin composition containing the polyisocyanate composition according to any one of (19) to (23) and a polyol.
(25) The resin composition according to (24), which is a pressure-sensitive adhesive composition.

According to the polyisocyanate composition of the above aspect, a pressure-sensitive adhesive sheet obtained by curing the polyisocyanate composition alone and having good flexibility and excellent adhesiveness, cohesiveness, curability and transparency can be obtained. The polyisocyanate composition to be obtained can be provided.

Further, according to the polyisocyanate composition of the above aspect, the compatibility with the main agent in a low temperature environment of about −10 ° C. is good, and the low temperature of about −10 ° C. and about 23 ° C. when the coating film is formed. It is possible to provide a polyisocyanate composition having excellent flexibility at room temperature. The resin composition of the above aspect contains the polyisocyanate composition and is excellent in flexibility at a low temperature of about −10 ° C. and a normal temperature of about 23 ° C. when formed into a coating film.

Hereinafter, a mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be modified in various ways without departing from the gist thereof.

In addition, in this specification, a "polyol" means a compound which has two or more hydroxy groups (-OH) in one molecule.
Further, in the present specification, "polyisocyanate" means a reaction product in which a plurality of monomer compounds having two or more isocyanate groups (-NCO) are bonded.
Further, in the present specification, unless otherwise specified, "(meth) acrylic" includes methacrylic and acrylic, and "(meth) acrylate" includes methacrylate and acrylate.

<< Polyisocyanate composition 1 >>
The polyisocyanate composition 1 of the present embodiment contains a diisocyanate, a bifunctional polyol (A1) having a number average molecular weight of 1500 or more (hereinafter, simply referred to as “polyester (A1)”), and a number average molecular weight of 500 or more. It is derived from a certain trifunctional or higher functional polyol (B1) (hereinafter, simply referred to as "polyol (B1)"). That is, the polyisocyanate composition 1 of the present embodiment is a reaction product of diisocyanate and the above two types of polyols, and contains polyisocyanate modified with the above two types of polyols. The diisocyanate is at least one selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates.

In the polyisocyanate composition 1 of the present embodiment, the molar ratio of the isocyanate group of the diisocyanate to the hydroxyl group of the polyol (A1) and the polyol (B1) (isocyanate group / molar ratio of hydroxyl group) is 2 or more and 30 or less, and 2.6. 30 or more and 25 or less are preferable, 3.5 or more and 24 or less are further preferable, 5 or more and 23 or less are particularly preferable, and 5 or more and 20 or less are most preferable.
The molar ratio of isocyanate groups / hydroxyl groups is calculated by using, for example, the molar amount of the hydroxyl groups of the polyol (A1) and the polyol (B1) used in the production of the polyisocyanate composition 1 and the molar amount of the isocyanate groups of the diisocyanate. Can be done.

The weight average molecular weight of the polyisocyanate composition 1 of the present embodiment is 1400 or more, preferably 1500 or more.
The upper limit of the weight average molecular weight of the polyisocyanate composition 1 of the present embodiment is not particularly limited, but may be 100,000.
The weight average molecular weight of the polyisocyanate composition 1 of the present embodiment can be measured by, for example, gel permeation chromatography (hereinafter, may be abbreviated as "GPC").

By having the above-mentioned structure, the polyisocyanate composition 1 of the present embodiment exhibits higher flexibility than the conventional one, and the flexibility of the cured film obtained by curing the polyisocyanate composition 1 alone becomes good. Further, by using the polyisocyanate composition 1 of the present embodiment, a pressure-sensitive adhesive sheet having excellent adhesiveness, cohesive force, curability and transparency can be obtained.

Next, the details of each component of the polyisocyanate composition 1 of the present embodiment will be described below.

<Polyisocyanate>
The polyisocyanate composition 1 of the present embodiment may be a polyisocyanate having all the structural units derived from the diisocyanate, the polyol (A1) and the polyol (B1) in one molecule, and the diisocyanate, the polyol (polyol) in one molecule. It may be a mixture of polyisocyanates having a structural unit derived from at least one selected from the group consisting of A1) and a polyol (B1).

The polyisocyanate can have at least one structure selected from the group consisting of an allophanate structure, a uretdione structure, an iminooxadiazinedione structure, an isocyanurate structure, a urea structure, a urethane structure, and a biuret structure. Among them, it is preferable to have at least one structure selected from the group consisting of a urethane structure, an allophanate structure, a biuret structure, a urea structure, and an isocyanurate group, and it is more preferable to include a urethane structure.

[Diisocyanate]
The diisocyanate is at least one selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates.

The aliphatic diisocyanate is not limited to the following, and is, for example, 1,4-diisocyanatobutane, 1,5-diisocyanatopentane, ethyl (2,6-diisocyanato) hexanoate, 1,6-diisocyanate. Natohexane (hereinafter sometimes abbreviated as "HDI"), 1,9-diisocyanatononan, 1,12-diisocyanatododecane, 2,2,4- or 2,4,4-trimethyl-1 , 6-Diisocyanatohexane and the like. These aliphatic diisocyanates may be used alone or in combination of two or more.

The alicyclic diisocyanate is not limited to the following, but for example, 1,3- or 1,4-bis (isocyanatomethyl) cyclohexane (hereinafter, may be abbreviated as "hydrogenated XDI"), 1 , 3- or 1,4-diisocyanatocyclohexane, 3,5,5-trimethyl1-isocyanato-3- (isocyanatomethyl) cyclohexane (hereinafter, may be abbreviated as "IPDI"), 4-4' -Diisocyanato-dicyclohexylmethane (hereinafter, may be abbreviated as "hydrogenated MDI"), 2,5- or 2,6-diisocyanatomethylnorbornane and the like can be mentioned. These alicyclic diisocyanates may be used alone or in combination of two or more.

Any of these aliphatic diisocyanates and alicyclic diisocyanates may be used alone, or two or more kinds of aliphatic diisocyanates and alicyclic diisocyanates may be used in combination.
Further, from the viewpoint of flexibility, the mass ratio of the alicyclic polyisocyanate to the aliphatic diisocyanate is preferably 0/100 or more and 30/70 or less.

Among them, as the diisocyanate, HDI, IPDI, hydrogenated XDI, or hydrogenated MDI is preferable, HDI or IPDI is more preferable, and HDI is further preferable.

In addition to the above-mentioned diisocyanate, an isocyanate monomer as shown below may be further used for producing the polyisocyanate.
(1) Aromatic diisocyanates such as diphenylmethane-4,4'-diisocyanate (MDI), 1,5-naphthalenediocyanate, tolylene diisocyanate (TDI), xylylene diisocyanate, m-tetramethylxylylene diisocyanate (TMXDI).
(2) 4-Isocyanate Methyl-1,8-octamethylene diisocyanate (hereinafter, may be referred to as "NTI"), 1,3,6-hexamethylene triisocyanate (hereinafter, may be referred to as "HTI"). , Bis (2-isocyanatoethyl) 2-isocyanatoglutarate (hereinafter, may be referred to as "GTI"), lysine triisocyanate (hereinafter, may be referred to as "LTI") and the like.

[Polyol (A1) and Polyol (B1)]
The polyol (A1) is a bifunctional polyol (diol) having a number average molecular weight of 1500 or more.
The polyol (B1) is a polyol having a number average molecular weight of 500 or more and trifunctional or higher.

The number average molecular weight of the polyol (A1) is 1500 or more, preferably 1800 or more. When the number average molecular weight of the polyol (A1) is at least the above lower limit value, the hardness of the cured film obtained by curing the polyisocyanate composition alone is low, and the flexibility is good.
On the other hand, the upper limit of the number average molecular weight of the polyol (A1) is not particularly limited, but can be, for example, 7000, preferably 6000, more preferably 5000, and 4200. More preferred.
The number average molecular weight Mn of the polyol (A1) is, for example, a polystyrene-based number average molecular weight measured by GPC. When two or more kinds of polyols (A1) are mixed and used, the number average molecular weight of the mixture is calculated.

The number average molecular weight of the polyol (B1) is 500 or more, preferably 800 or more. When the number average molecular weight of the polyol (B1) is at least the above lower limit value, the hardness of the cured film obtained by curing the polyisocyanate composition alone is low, and the flexibility is good.
On the other hand, the upper limit of the number average molecular weight of the polyol (B1) is not particularly limited, but can be, for example, 3000, preferably 2200, more preferably 1500, and 1300. More preferred.
The number average molecular weight Mn of the polyol (B1) is, for example, a polystyrene-based number average molecular weight measured by GPC. When two or more kinds of polyols (B1) are mixed and used, the number average molecular weight of the mixture is calculated.

The polyol (A1) is preferably at least one bifunctional polyol (diol) selected from the group consisting of polyester polyols, polyether polyols, epoxy polyols, polyolefin polyols, and polycarbonate polyols, and is preferably bifunctional polyesters. It is more preferably a polyol.

Examples of the bifunctional polyester polyol include the polyester polyol according to any one of (1) and (2) below. (1) A polyester polyol obtained by a condensation reaction between a dibasic acid alone or a mixture of two or more kinds and a dihydric alcohol alone or a mixture of two or more kinds. (2) A polycaprolactone polyol obtained by ring-opening polymerization of ε-caprolactone with a divalent alcohol.
Examples of the dibasic acid include succinic acid, adipic acid, dimer acid, maleic anhydride, phthalic acid anhydride, isophthalic acid, terephthalic acid, and carboxylic acids such as 1,4-cyclohexanedicarboxylic acid.
Examples of the divalent alcohol include ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, trimethylpentanediol, and cyclohexanediol.

Among them, as the bifunctional polyester polyol, a bifunctional polycaprolactone polyol is preferable.

Examples of commercially available bifunctional polycaprolactone polyols include the trade name "Plaxel 210" (number average molecular weight 1000, hydroxyl value 112.8 mgKOH / g, acid value 0.09 mgKOH / g) manufactured by Daicel. 210CP ”(number average molecular weight 1000, hydroxyl value 112.8 mgKOH / g, acid value 0.16 mgKOH / g), trade name“ Praxel 212 ”(number average molecular weight 1250, hydroxyl value 90.8 mgKOH / g, acid value 0.09 mgKOH” / G), trade name "Plaxel 212CP" (number average molecular weight 1250, hydroxyl value 90.2 mgKOH / g, acid value 0.14 mgKOH / g), "Pluxel 220" (number average molecular weight 2000, hydroxyl value 56.7 mgKOH / g) , Acid value 0.06 mgKOH / g), "Pluxel 220 CPB" (number average molecular weight 2000, hydroxyl value 57.2 mgKOH / g, acid value 0.16 mgKOH / g), "Pluxel 220 CPT" (number average molecular weight 2000, hydroxyl value 56) .6 mgKOH / g, acid value 0.02 mgKOH / g), "Pluxel 230" (number average molecular weight 3000, hydroxyl value 37.6 mgKOH / g, acid value 0.07 mgKOH / g), "Pluxel 240 (number average molecular weight 4000, A hydroxyl value of 28.5 mgKOH / g, an acid value of 0.07 mgKOH / g) and the like can be mentioned.
As the bifunctional polycaprolactone polyol, it is preferable to use one having a lower acid value from the viewpoint of hydrolysis resistance and reaction stability during polyisocyanate synthesis.

The polyol (B1) may be a trifunctional or higher functional polyol, preferably a trifunctional or higher and 10-functional or lower polyol, more preferably a trifunctional or higher and 7-functional or lower polyol, and further preferably a trifunctional or higher and 5-functional or lower polyol. Preferably, a trifunctional or higher and tetrafunctional or lower polyol is particularly preferable, and a trifunctional polyol (triol) is most preferable.
The trifunctional polyol (triol) is preferably at least one trifunctional polyol (triol) selected from the group consisting of polyester polyols, polyether polyols, epoxy polyols, polyolefin polyols, and polycarbonate polyols. More preferably, it is a functional polyester polyol.

Examples of the trifunctional polyester polyol include the polyester polyol according to any one of (1) and (2) below. (1) A polyester polyol obtained by a condensation reaction between a dibasic acid alone or a mixture of two or more kinds and a trihydric alcohol alone or a mixture of two or more kinds. (2) A polycaprolactone polyol obtained by ring-opening polymerization of ε-caprolactone with a trihydric alcohol.
Examples of the dibasic acid include succinic acid, adipic acid, dimer acid, maleic anhydride, phthalic acid anhydride, isophthalic acid, terephthalic acid, and carboxylic acids such as 1,4-cyclohexanedicarboxylic acid.
Examples of the trihydric alcohol include trimethylolpropane, glycerin, pentaerythritol, 2-methylolpropanediol, and ethoxylated trimethylolpropane.

Among them, the trifunctional polyester polyol is preferably a trifunctional polycaprolactone polyol.

Examples of commercially available trifunctional polycaprolactone polyols include "Plaxel 305" (number average molecular weight 550, hydroxyl value 305.6 mgKOH / g, acid value 0.50 mgKOH / g) manufactured by Daicel. 308 ”(number average molecular weight 850, hydroxyl value 195.3 mgKOH / g, acid value 0.38 mgKOH / g),“ Praxel 309 ”(number average molecular weight 900, hydroxyl value 187.3 mgKOH / g, acid value 0.20 mgKOH / g) ), "Pluxel 312" (number average molecular weight 1250, hydroxyl value 136.1 mgKOH / g, acid value 0.38 mgKOH / g), "Pluxel 320" (number average molecular weight 2000, hydroxyl value 85.4 mgKOH / g, acid value 0) .29 mgKOH / g) and the like.

In the polyisocyanate composition 1 of the present embodiment, the mass ratio of the polyol (A1) to the polyol (B1) (mass ratio of (A1) / (B1)) is 0.1 / 99.9 or more and 99.9 / 0. 1 is preferable, 1/99 or more and 99/1 or less are more preferable, 3/97 or more and 90/10 or less are further preferable, 5/95 or more and 80/20 or less are particularly preferable, and 7/93 or more and 70/30 or less are the most preferable. preferable.
When the mass ratio of (A1) / (B1) is at least the above lower limit value, the hardness of the cured film obtained by curing the polyisocyanate composition alone is low, and the flexibility becomes better. Further, an adhesive sheet having excellent adhesiveness and flexibility can be obtained. On the other hand, when the mass ratio of (A1) / (B1) is not more than the above upper limit value, the pressure-sensitive adhesive sheet having excellent adhesiveness, flexibility and cohesive force becomes better.
The mass ratio of (A1) / (B1) can be calculated, for example, from the blending amount of each polyol at the time of producing the polyisocyanate composition 1.

In the polyisocyanate composition 1 of the present embodiment, the content (charged amount) of the polyol (A1) is 0.1 part by mass or more and 250 parts by mass or less with respect to 100 parts by mass of diisocyanate, and 0.1 part by mass. It is preferably 210 parts by mass or more, more preferably 0.1 part by mass or more and 170 parts by mass or less, still more preferably 0.5 parts by mass or more and 100 parts by mass or less, and 1 part by mass or more. It is more preferably 50 parts by mass or less, further preferably 1.5 parts by mass or more and 40 parts by mass or less, and particularly preferably 1.7 parts by mass or more and 38 parts by mass or less.
When the content of the polyol (A1) is at least the above lower limit value, the hardness of the cured film obtained by curing the polyisocyanate composition alone is low, and the flexibility becomes better. Further, an adhesive sheet having better adhesiveness and curability can be obtained. On the other hand, when the content of the polyol (A1) is not more than the above upper limit value, the polyisocyanate composition 1 can be maintained in a liquid state without gelling during production, and has flexibility when formed into a resin film. It will be better.
The content of the polyol (A1) can be calculated, for example, from the blending amount of the diisocyanate and the polyol (A1) at the time of producing the polyisocyanate composition 1.

In the polyisocyanate composition 1 of the present embodiment, the content (charged amount) of the polyol (B1) is 1 part by mass or more and 190 parts by mass or less, and 1 part by mass or more and 140 parts by mass with respect to 100 parts by mass of diisocyanate. It is preferably 1 part by mass or more and 90 parts by mass or less, more preferably 2 parts by mass or more and 80 parts by mass or less, and 5 parts by mass or more and 70 parts by mass or less. It is even more preferably 10 parts by mass or more and 60 parts by mass or less, and particularly preferably 12 parts by mass or more and 50 parts by mass or less.
When the content of the polyol (B1) is not more than the above upper limit, the polyisocyanate composition 1 can be maintained in a liquid state without gelling during production, and the curability and flexibility of the resin film can be improved. It will be better. On the other hand, when the content of the polyol (B1) is at least the above lower limit value, the hardness of the cured film obtained by curing the polyisocyanate composition alone is low, and the flexibility becomes better. Further, an adhesive sheet having better adhesiveness and curability can be obtained.
The content of the polyol (B1) can be calculated, for example, from the blending amount of the diisocyanate and the polyol (B1) at the time of producing the polyisocyanate composition 1.

<Manufacturing method of polyisocyanate composition 1>
The polyisocyanate is obtained by reacting the above diisocyanate with a polyol (A1) and a polyol (B1). Hereinafter, the polyol (A1) and the polyol (B1) may be collectively referred to as a polyol.

The polyol (A1) and the polyol (B1) can be used alone or as a mixture, respectively. When used as a mixture, it may be mixed before reacting with diisocyanate, or each polyol may be independently reacted with diisocyanate to form polyisocyanate and then mixed.
That is, as a method for producing the polyisocyanate composition 1, for example, a method of simultaneously reacting a diisocyanate with a polyol (A1) and a polyol (B1) to obtain a polyisocyanate composition 1; a diisocyanate and a polyol (A1). A method for obtaining a polyisocyanate composition 1 by mixing a reaction of diisocyanate with a polyol (B1); a reaction of the diisocyanate with a polyol (A1) or a polyol (B1). After that, a method of further reacting the remaining polyol to obtain the polyisocyanate composition 1 and the like can be mentioned. Further, using these methods, a polyisocyanate composition obtained by first adding a part of the polyol (A1) to obtain the polyisocyanate composition 1 and then adding the remaining polyol (A1). A method of reacting with 1 to obtain the polyisocyanate composition 1 may also be used.

The amount of the polyol (A1) and the polyol (B1) is preferably blended so that the mass ratio of the polyol (A1) to the polyol (B1) is within the above range.

At the time of the reaction, the molar ratio of the isocyanate group of the diisocyanate to the hydroxyl group of the polyol (A1) and the polyol (B1) (isocyanate group / molar ratio of hydroxyl group) is 2 or more and 30 or less, preferably 2.6 or more and 30 or less, and 3 or more. 25 or less is more preferable, 3.5 or more and 24 or less is further preferable, 5 or more and 23 or less is particularly preferable, and 5 or more and 20 or less is most preferable.

The reaction between the polyol and diisocyanate is performed as follows. The reaction temperature is usually room temperature (about 23 ° C.) or higher and 200 ° C. or lower, preferably 60 ° C. or higher and 120 ° C. or lower. If the reaction temperature is at least the above lower limit, the reaction time will be shorter, while if it is at least the above upper limit, the increase in viscosity of the polyisocyanate due to an undesired side reaction can be further avoided, and the resulting polyisocyanate will be colored. It can be avoided more.

The reaction may be carried out without a solvent, or may be carried out with any solvent inert to the isocyanate group. If necessary, a known catalyst may be used in order to promote the reaction between the isocyanate group and the hydroxyl group.

<Physical characteristics of polyisocyanate composition 1>
The isocyanate group content (NCO group content) of the polyisocyanate composition 1 of the present embodiment is 1% by mass or more with respect to the total mass of the polyisocyanate composition 1 in a state where it does not substantially contain a solvent or diisocyanate. It is preferably 10% by mass or less, more preferably 1.5% by mass or more and 9.8% by mass or less, further preferably 2.0% by mass or more and 9.6% by mass or less. It is even more preferably 5% by mass or more and 9.5% by mass or less, further preferably 2.75% by mass or more and 9.5% by mass or less, and 3.0% by mass or more and 9.5% by mass or less. It is particularly preferable, and it is most preferable that it is 3.15% by mass or more and 9.5% by mass or less.
The NCO group content can be determined, for example, by reacting the isocyanate group of the polyisocyanate composition 1 with an excess amine (dibutylamine or the like) and back-titrating the remaining amine with an acid such as hydrochloric acid.

The average number of isocyanate functional groups of the polyisocyanate composition 1 of the present embodiment is preferably 2 or more and 6 or less, preferably 2 or more and 5.8 or less, and 2.5 or less, in terms of enhancing the curability and cohesive force of the pressure-sensitive adhesive composition. More than 5.5 or less is more preferable.
The average number of isocyanate functional groups of the polyisocyanate composition 1 of this embodiment can be measured by using the method described in Examples described later.

≪Hardened film≫
The cured film of the present embodiment is formed by curing the above-mentioned polyisocyanate composition 1.

The cured film of this embodiment has low hardness and good flexibility.

For the cured film of the present embodiment, for example, the above-mentioned polyisocyanate composition 1 is diluted or dissolved with a solvent as necessary, coated on the adherend using a coater or the like, and if necessary. It can be manufactured by drying and curing with heat.

In the cured film of the present embodiment, only the above-mentioned polyisocyanate composition 1 is coated on glass, stored at 23 ° C. in a 65% humidity environment for 168 hours, and further heated at 50 ° C. for 24 hours, and then air. In the case of a cured film having a film thickness of 40 μm formed by the reaction between the moisture in the mixture and the polyisocyanate composition 1, the König hardness of the cured film in an environment of 23 ° C. is 60 times or less and 57 times or less. It is preferably 55 times or less, more preferably 54 times or less. When the König hardness is not more than the above upper limit, the hardness is low and the flexibility is superior.

≪Coating film≫
The above-mentioned polyisocyanate composition 1 can also be used as a curing agent component of a coating composition. That is, the coating film of the present embodiment is formed by curing a coating composition containing the above-mentioned polyisocyanate composition 1 and a polyol.

The coating film of the present embodiment has the above-mentioned polyisocyanate composition 1, a glass transition temperature of 29.1 ° C., a hydroxyl value of 139 mgKOH / g with respect to a resin solid content, and a weight average molecular weight of 2.56. When the coating composition containing the acrylic polyol of × 10 ⁴ is cured at 90 ° C. for 30 minutes and stored at 23 ° C. in a 65% humidity environment for 168 hours, the coating film has a thickness of 40 μm. A test piece having a film width of 10 mm and a length of 100 mm was set in a tensile tester so that the gripping tool distance was 20 mm, and the elongation rate in the tensile test measured at a speed of 20 mm / min was 50% or more, and The stress at an elongation rate of 140% is 28 MPa or less. The elongation rate is preferably 100% or more, more preferably 130% or more, further preferably 140% or more, and particularly preferably 150% or more. On the other hand, the upper limit of the elongation rate can be, for example, 300%.
The stress at an elongation rate of 140% is preferably 27 MPa or less, more preferably 25 MPa or less, and even more preferably 20 MPa or less. On the other hand, the lower limit of the stress when the elongation rate is 140% can be, for example, 1 MPa.
When the elongation is not less than the lower limit and the stress at the elongation of 140% is not more than the upper limit, the flexibility of the coating film is more excellent.

≪Adhesive composition≫
The pressure-sensitive adhesive composition of the present embodiment contains the above-mentioned polyisocyanate composition 1 and a crosslinkable functional group-containing polymer having a glass transition temperature of 0 ° C. or lower.

By containing the above-mentioned polyisocyanate composition 1 in the pressure-sensitive adhesive composition of the present embodiment, a pressure-sensitive adhesive layer having higher flexibility than before can be formed, and the pressure-sensitive adhesiveness, cohesive force, curability and transparency can be formed. An adhesive sheet with excellent properties can be obtained.

Next, the details of each component contained in the pressure-sensitive adhesive composition of the present embodiment will be described below.

<Crosslinkable functional group-containing polymer>
The glass transition temperature of the crosslinkable functional group-containing polymer is 0 ° C. or lower, preferably −70 ° C. or higher and 0 ° C. or lower, more preferably −70 ° C. or higher and −5 ° C. or lower, and further preferably −70 ° C. or higher and −10 ° C. or lower. , −70 ° C. or higher and −15 ° C. or lower is particularly preferable. When the glass transition temperature Tg of the crosslinkable functional group-containing polymer is within the above range, the adhesive strength and cohesive strength of the cured product of the pressure-sensitive adhesive composition tend to be more excellent. The glass transition temperature of the crosslinkable functional group-containing polymer is, for example, the differential scanning calorimetry obtained by removing the organic solvent and water in the solution in which the crosslinkable functional group-containing polymer is dissolved or dispersed under reduced pressure and then vacuum-drying. A value measured under the condition of a heating rate of 5 ° C./min using a DSC) measuring device can be used as the glass transition temperature.

The weight average molecular weight Mw of the crosslinkable functional group-containing polymer is preferably 3.0 × 10 ⁵ or more and 2.5 × ¹⁰⁶ or less, and preferably 4.0 × 10 ⁵ or more and 2.3 × ¹⁰⁶ or less. Is more preferable, 4.5 × 10 ⁵ or more and 2.0 × ¹⁰⁶ is more preferable, and 4.5 × 10 ⁵ or more and 1.8 × ¹⁰⁶ or less is particularly preferable. When the weight average molecular weight of the crosslinkable functional group-containing polymer is within the above range, the adhesive strength, cohesive strength, and durability of the cured product of the pressure-sensitive adhesive composition tend to be more excellent. The weight average molecular weight Mw of the polyol can be measured, for example, by using the method described in Examples described later.

The crosslinkable functional group-containing polymer may be any polymer containing a crosslinkable functional group that can react with the isocyanate group of the polyisocyanate composition 1. Examples of the crosslinkable functional group include a hydroxyl group, a thiol group, an amino group, a carboxy group, an epoxy group and the like, and among them, a hydroxyl group is preferable. That is, as the crosslinkable functional group-containing polymer, a polyol is preferable.
Specific examples of the crosslinkable functional group-containing polymer include an aliphatic hydrocarbon polyol, a polyether polyol, a polyester polyol, an epoxy resin, a fluorine-containing polyol, an acrylic polymer, and a urethane polymer.
Among them, the crosslinkable functional group-containing polymer is preferably an acrylic polymer.

[Aliphatic hydrocarbon polyol]
Examples of the aliphatic hydrocarbon polyol include hydroxyl-terminated polybutadiene and its hydrogenated additive.

[Polyether polyol]
Examples of the polyether polyol include those obtained by using any of the following methods (1) to (3). (1) A polyether polyol or a polytetramethylene ether glycol obtained by adding a alkylene oxide alone or a mixture to a polyhydric alcohol alone or a mixture. (2) A polyether polyol obtained by reacting an alkylene oxide with a polyfunctional compound. (3) A so-called polymer polyol obtained by polymerizing acrylamide or the like using the polyether polyol obtained in (1) or (2) as a medium.
Examples of the polyhydric alcohol include glycerin and propylene glycol.
Examples of the alkylene oxide include ethylene oxide and propylene oxide.
Examples of the polyfunctional compound include ethylenediamine and ethanolamine.

[Polyester polyol]
Examples of the polyester polyol include any of the following polyester polyols (1) and (2). (1) A polyester polyol resin obtained by a condensation reaction between a dibasic acid alone or a mixture of two or more kinds and a polyhydric alcohol alone or a mixture of two or more kinds. (2) A polycaprolactone polyol obtained by ring-opening polymerization of ε-caprolactone with a polyhydric alcohol.
Examples of the dibasic acid include succinic acid, adipic acid, dimer acid, maleic anhydride, phthalic acid anhydride, isophthalic acid, terephthalic acid, and carboxylic acids such as 1,4-cyclohexanedicarboxylic acid.
Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, trimethylpentanediol, cyclohexanediol, trimethylolpropane, glycerin, and pentaerythritol. , 2-Methylolpropanediol, ethoxylated trimethylolpropane and the like.

[Epoxy resin]
Examples of the epoxy resin include novolak type epoxy resin, β-methylepicro type epoxy resin, cyclic oxylan type epoxy resin, glycidyl ether type epoxy resin, glycol ether type epoxy resin, epoxy type aliphatic unsaturated compound, and epoxidized fatty acid ester. , Epoxy resins such as ester-type polyvalent carboxylic acids, aminoglycidyl-type epoxy resins, halogenated epoxy resins, resorcin-type epoxy resins, and resins obtained by modifying these epoxy resins with amino compounds, polyamide compounds, and the like.

[Fluorine-containing polyol]
Examples of the fluorine-containing polyol include fluoroolefins, cyclohexyl vinyl ethers, and hydroxyalkyls disclosed in Reference 1 (Japanese Patent Laid-Open No. 57-34107) and Reference 2 (Japanese Patent Laid-Open No. 61-275311). Examples thereof include copolymers such as vinyl ether and monocarboxylic acid vinyl ester.

[Acrylic polymer]
The acrylic polymer contains one or more polymerizable (meth) acrylic monomer units having a crosslinkable functional group. The crosslinkable functional group preferably contains a hydroxyl group, a carboxy group, or an epoxy group, and more preferably contains a hydroxyl group.
The acrylic polymer may contain one type of crosslinkable functional group alone, or may contain two or more types of different types of crosslinkable functional groups in combination. That is, the acrylic polymer may be obtained by polymerizing one kind of polymerizable (meth) acrylic monomer having a crosslinkable functional group alone, or may be a polymer having different kinds of crosslinkable functional groups (meth). It may be obtained by combining two or more kinds of acrylic monomers and copolymerizing them.
The acrylic polymer may contain one or more polymerizable acrylic monomer units having no crosslinkable functional group in addition to the polymerizable (meth) acrylic monomer unit having a crosslinkable functional group.
That is, the acrylic polymer is one kind with a polymerizable (meth) acrylic monomer having one or more kinds of crosslinkable functional groups, or a polymerizable (meth) acrylic monomer having one or more kinds of crosslinkable functional groups. It can be obtained by copolymerizing with the above-mentioned polymerizable (meth) acrylic monomer having no crosslinkable functional group.

Examples of the polymerizable (meth) acrylic monomer having a crosslinkable functional group include those shown in the following (i) to (v). These may be used alone or in combination of two or more. (I) Acrylic acid ester having a hydroxyl group such as -2-hydroxyethyl acrylate, -2-hydroxypropyl acrylate, -2-hydroxybutyl acrylate, -4-hydroxybutyl acrylate, -6-hydroxyhexyl acrylate, etc. Kind. (Ii) Methacrylic acid ester having a hydroxyl group such as -2-hydroxyethyl methacrylate, -2-hydroxypropyl methacrylate, -2-hydroxybutyl methacrylate, -4-hydroxybutyl methacrylate, -6-hydroxyhexyl methacrylate and the like. Kind. (Iii) (meth) acrylic acid esters having a polyvalent hydroxy group such as acrylic acid monoester or methacrylic acid monoester of glycerin, acrylic acid monoester or methacrylic acid monoester of trimethylolpropane. (Iv) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid. (V) A polymerizable monomer having an epoxy group such as glycidyl methacrylate, 1,2-epoxy-4-vinylcyclohexane, allyl glycidyl ether, and 4-hydroxybutyl acrylate glycidyl ether.

Examples of the polymerizable (meth) acrylic monomer having no crosslinkable functional group include those shown in the following (i) to (iii). These may be used alone or in combination of two or more. (I) Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, -n-butyl (meth) acrylate, isobutyl (meth) acrylate, (meth) ) Acrylic acid-sec-butyl, (meth) acrylate-tert-butyl, (meth) acrylate pentyl, (meth) acrylate isopentyl, (meth) acrylate hexyl, (meth) acrylate -2-ethylhexyl, (Meta) heptyl acrylate, (meth) octyl acrylate, (meth) isooctyl acrylate, (meth) nonyl acrylate, (meth) isononyl acrylate, (meth) decyl acrylate, (meth) isodecyl acrylate, ( Undecyl acrylate, (meth) dodecyl acrylate ((meth) lauryl acrylate), (meth) tridecyl acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, (meth) Heptadecyl acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, nonadecil (meth) acrylate, eicocil (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, etc. (Meta) Acrylic acid esters. (Ii) Unsaturated amides such as (meth) acrylamide, N-methylol acrylamide, diacetone acrylamide, and dimethylaminopropyl acrylamide. (Iii) Styrene, vinyltoluene, vinyl acetate, (meth) acrylonitrile, N-vinylpyrrolidone, N-vinylcaprolactam, acryloylmorpholine, (meth) dimethylaminoethyl acrylate, (meth) diethylaminoethyl acrylate.

Further, as other monomers copolymerizable with the polymerizable (meth) acrylic monomer having a crosslinkable functional group, JP-A No. 1-261409 (Reference 3) and JP-A-3-006273 (Reference). The polymerizable ultraviolet stable monomer disclosed in Document 4) and the like may be used.

Specifically, as the polymerizable ultraviolet stable monomer, for example, 4- (meth) acryloyloxy-2, 2,6,6-tetramethylpiperidine, 4- (meth) acryloylamino-2, 2,6 , 6-Tetramethylpiperidine, 1-crotonoyl-4-crotonoyloxy-2, 2,6,6-tetramethylpiperidine, 2-hydroxy-4- (3-methacrylicoxy-2-hydroxypropoxy) benzophenone and the like. Be done.

Above all, it is preferable that the acrylic polymer contains at least one acrylic acid ester unit having an alkyl group having 1 or more and 20 or less carbon atoms at the end of the ester group.
The acrylic acid ester unit having an alkyl group having 1 or more and 20 or less carbon atoms at the terminal of the ester group may or may not contain a crosslinkable functional group.

The alkyl group of the acrylic acid ester unit containing a crosslinkable functional group has 1 or more and 20 or less carbon atoms, preferably 1 or more and 18 or less, and more preferably 2 or more and 18 or less.
On the other hand, the number of carbon atoms of the alkyl group of the acrylic acid ester unit containing no crosslinkable functional group is 1 or more and 20 or less, preferably 1 or more and 18 or less, more preferably 2 or more and 18 or less, and 4 or more and 18 or less. More preferred.

For example, an acrylic polymer can be obtained by solution-polymerizing the above-mentioned monomer component in the presence of a known radical polymerization initiator such as a peroxide or an azo compound and diluting it with an organic solvent or the like as necessary. can.

When an aqueous-based acrylic polymer is obtained, it can be produced by a known method such as solution polymerization of an olefinically unsaturated compound to convert it into an aqueous layer or emulsion polymerization. In that case, water solubility or water dispersibility can be imparted by neutralizing an acidic portion such as a carboxylic acid-containing monomer such as acrylic acid or methacrylic acid or a sulfonic acid-containing monomer with an amine or ammonia.

[Isocyanate group / hydroxyl group]
The molar ratio of the isocyanate group of the polyisocyanate composition 1 to the hydroxyl group of the polyol contained in the resin composition of the present embodiment (isocyanate group / molar ratio of hydroxyl group) is determined by the physical properties of the required resin film, but is usually used. , 0.01 or more and 22.5 or less.

<Other ingredients>
The resin composition of the present embodiment may further contain other additives.
Examples of other additives include curing agents other than the polyisocyanate composition 1 capable of reacting with polyols, curing catalysts, solvents, pigments (extension pigments, coloring pigments, metallic pigments, etc.), tackifier resins, and photopolymerization initiators. , UV absorber, light stabilizer, radical stabilizer, anti-yellowing agent that suppresses coloring during baking process, coating surface conditioner, flow conditioner, pigment dispersant, defoaming agent, thickener, film-forming aid And so on.

Examples of the curing agent include melamine resin, urea resin, epoxy group-containing compound or resin, carboxy group-containing compound or resin, acid anhydride, alkoxysilane group-containing compound or resin, hydrazide compound and the like.

The curing catalyst may be a basic compound or a Lewis acidic compound.
Examples of the basic compound include metal hydroxides, metal alkoxides, metal carboxylates, metal acetyl acetylates, hydroxides of onium salts, onium carboxylates, halides of onium salts, and metal salts of active methylene compounds. Examples thereof include onium salts of active methylene compounds, aminosilanes, amines, phosphins and the like. As the onium salt, an ammonium salt, a phosphonium salt or a sulfonium salt is suitable.
Examples of the Lewis acidic compound include an organic tin compound, an organic zinc compound, an organic titanium compound, and an organic zirconium compound.

Examples of the solvent include 1-methylpyrrolidone, ethylene glycol monoethyl ether, diethylene glycol monoethyl ether, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether, 3-methoxy-3-methyl. -1-butanol, ethylene glycol diethyl ether, diethylene glycol diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether (DPDM), propylene glycol dimethyl ether, methyl ethyl ketone, acetone, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, ethanol, methanol , Iso-propanol, 1-propanol, iso-butanol, 1-butanol, tert-butanol, 2-ethylhexanol, cyclohexanol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,4-butane Examples thereof include diol, 1,3-butanediol, ethyl acetate, isopropyl acetate, butyl acetate, toluene, xylene, pentane, iso-pentane, hexane, iso-hexane, cyclohexane, solvent naphtha, and mineral spirit. These solvents may be used alone or in combination of two or more.

In addition, pigments (constitution pigments, coloring pigments, metallic pigments, etc.), ultraviolet absorbers, light stabilizers, radical stabilizers, anti-yellowing agents that suppress coloring during the baking process, coating surface adjusting agents, flow adjusting agents, pigments As the dispersant, defoaming agent, thickening agent and film-forming auxiliary, known ones can be appropriately selected and used.

<Manufacturing method of adhesive composition>
The pressure-sensitive adhesive composition can be produced by a conventionally known method. For example, a melt-kneading method using a general miscible machine such as a Banbury mixer, a single-screw extruder, a twin-screw extruder, a conider, or a multi-screw screw extruder. A method of heating and removing the solvent after coating on the Kizai film is used.

The pressure-sensitive adhesive composition of the present embodiment may be foamed in order to reduce the weight, make it softer, and improve the adhesion. Examples of the foaming method include a chemical method, a physical method, and the use of a heat-expandable microballoon. Bubbles can be distributed inside the material by adding a chemical foaming agent such as an inorganic foaming agent or an organic foaming agent, a physical foaming agent, or the like, or by adding a heat-expandable microballoon.

Further, by adding a hollow filler (already inflated balloon), weight reduction, flexibility, and improvement of adhesion may be achieved.

In the pressure-sensitive adhesive composition of the present embodiment, a pressure-sensitive adhesive resin may be added for adjusting the pressure-sensitive adhesive force and the cohesive force. Examples of the tackifying resin include a rosin-based tackifier resin, a terpene-based tackifier resin, a petroleum-based tackifier resin, and a styrene-based tackifier resin. These tackifier resins may be used alone or in combination of two or more. Further, the softening point of the tackifier resin is preferably 90 ° C. or higher and 160 ° C. or lower.

≪Adhesive sheet≫
The pressure-sensitive adhesive sheet of the present embodiment includes a base material and a pressure-sensitive adhesive layer on the base material.
The pressure-sensitive adhesive layer is made of a cured product of the pressure-sensitive adhesive composition described above.
In the pressure-sensitive adhesive sheet of the present embodiment, the pressure-sensitive adhesive layer is excellent in adhesiveness, curability and transparency.

The base material is not particularly limited, but for example, paper such as high-quality paper, coated paper, cast-coated paper, heat-sensitive paper, and inkjet paper; cloth such as woven cloth and non-woven cloth; polyvinyl chloride, synthetic paper, and polyethylene terephthalate (PET). ), Polyethylene, polyethylene, cellulose triacetate, cellulose diacetate, polystyrene, polycarbonate, nylon, polyvinyl alcohol, ethylene-vinyl acetate copolymer, resin film such as polyimide; porous resin film such as porous polypropylene film; PET, polyolefin A vapor-deposited film obtained by metal-depositing aluminum or the like on the like; a metal foil or the like is exemplified. The base material may be one whose surface has been peeled off.

In the pressure-sensitive adhesive sheet of the present embodiment, the thickness of the pressure-sensitive adhesive layer can be appropriately determined depending on the intended use, but is preferably 1 μm or more and 1000 μm or less, and more preferably 5 μm or more and 900 μm or less. It is more preferably 7 μm or more and 800 μm or less, and particularly preferably 9 μm or more and 700 μm or less.

The pressure-sensitive adhesive sheet of the present embodiment can be produced, for example, by applying a pressure-sensitive adhesive composition onto a substrate, drying it if necessary, and then curing it.
Examples of the method of applying the pressure-sensitive adhesive composition onto the substrate include a method of applying the pressure-sensitive adhesive composition using an applicator, a roll coater, a knife coater, a gravure coater, or the like. When drying is performed after the coating, for example, a heat-drying method in which the obtained laminate is placed in a dryer or the like and dried at a temperature of 50 ° C. or higher and 150 ° C. or lower for 1 minute or longer and 30 minutes or lower can be mentioned. .. Alternatively, other drying methods include, for example, natural drying, hot air drying, infrared drying and the like.

The heating temperature at the time of curing can be 70 ° C. or higher and 150 ° C. or lower, 75 ° C. or higher and 145 ° C. or lower, and 80 ° C. or higher and 140 ° C. or lower.

The pressure-sensitive adhesive sheet of the present embodiment includes a pressure-sensitive adhesive layer having a thickness of 50 μm, which is obtained by applying the pressure-sensitive adhesive composition onto a peel-treated polyethylene terephthalate film having a thickness of 38 μm, drying at 130 ° C. for 3 minutes, and curing the pressure-sensitive adhesive composition. The gel content calculated by wrapping the adhesive sheet in a mesh-like sheet after storing it in a 23 ° C. and 50% RH environment for 7 days, immersing it in ethyl acetate at 23 ° C. for 1 week, and drying it at 120 ° C. for 2 hours. The ratio is preferably 20% by mass or more and 99% by mass or less, more preferably 25% by mass or more and 99% by mass or less, further preferably 30% by mass or more and 99% by mass or less, and 35% by mass or more. It is particularly preferably 99% by mass or less, and most preferably 40% by mass or more and 99% by mass or less. When the gel fraction is at least the above lower limit, the curability is more excellent.
The gel fraction referred to here is a percentage of the mass of the pressure-sensitive adhesive sheet dried after being immersed in ethyl acetate with respect to the mass of the pressure-sensitive adhesive sheet before being immersed in ethyl acetate.

The pressure-sensitive adhesive sheet of the present embodiment has a width of 20 mm and includes a pressure-sensitive adhesive layer having a thickness of 50 μm, which is obtained by coating the pressure-sensitive adhesive composition on a polyethylene terephthalate film having a thickness of 25 μm, drying at 130 ° C. for 3 minutes, and curing the pressure-sensitive adhesive composition. An adhesive sheet having a length of 100 mm is stored at 23 ° C. in a 50% RH environment for 7 days, then crimped once with a 2 kg roller using a SUS304BA steel plate as an adherend, cured at 23 ° C. for 30 minutes, and then 23 ° C. The 180 degree peel adhesive force measured at a speed of 300 mm / min is preferably 0.05 N / 20 mm or more and 55 N / 20 mm or less, more preferably 0.07 N / 20 mm or more and 45 N / 20 mm or less, and 0. It is more preferably 1N / 20mm or more and 38N / 20mm or less, particularly preferably 0.12N / 20mm or more and 36N / 20mm or less, and most preferably 0.15N / 20mm or more and 33N / 20mm or less. When the 180-degree peel adhesive strength is at least the above lower limit value, the adhesiveness is more excellent.

In the pressure-sensitive adhesive sheet of the present embodiment, the pressure-sensitive adhesive composition is coated on a peel-treated polyethylene terephthalate film having a thickness of 38 μm, dried at 130 ° C. for 3 minutes, and cured to form a pressure-sensitive adhesive layer having a thickness of 50 μm. After peeling from the peeled polyethylene terephthalate film, the haze value measured by the haze meter of the adhesive sheet bonded on the glass having a haze value of 0.1% is 0.01% or more and 2% or less. It is preferably 0.01% or more and 1.8% or less, more preferably 0.01% or more and 1.5% or less, and 0.01% or more and 1.0% or less. It is particularly preferable that there is, and most preferably 0.01% or more and 0.8% or less. When the haze value is not more than the above upper limit value, the transparency is more excellent.

<< Polyisocyanate composition 2 >>
The polyisocyanate composition 2 of the present embodiment is derived from a diisocyanate and a polycaprolactone polyol (A2) and a polyether polyol (B2). That is, the polyisocyanate composition 2 of the present embodiment is a reaction product of diisocyanate with a polycaprolactone polyol (A2) and a polyether polyol (B2), and is a polycaprolactone polyol (A2) and a polyether polyol (B2). It contains modified polyisocyanates. The diisocyanate is at least one selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates.
The polyisocyanate composition 2 of the present embodiment contains 20 parts by mass or more of polypropylene glycol with respect to 100 parts by mass of the polyether polyol (B2).

As described above, the polyisocyanate composition 2 of the present embodiment exhibits higher flexibility than the conventional one by using two different types of polyols and containing polypropylene glycol as the polyether polyol (B2). A coating film having good compatibility with the main agent in a low temperature environment of about −10 ° C. and excellent flexibility at a low temperature of about −10 ° C. and a normal temperature of about 23 ° C. can be obtained.

Next, the details of each component of the polyisocyanate composition 2 of the present embodiment will be described below.

<Polyisocyanate>
The polyisocyanate composition 2 of the present embodiment may be a polyisocyanate having all the structural units derived from diisocyanate, polycaprolactone polyol (A2) and polyether polyol (B2) in one molecule, and may be in one molecule. It may be a mixture of polyisocyanates having a structural unit derived from at least one selected from the group consisting of diisocyanate, polycaprolactone polyol (A2) and polyether polyol (B2).

The polyisocyanate can have at least one structure selected from the group consisting of an allophanate structure, a uretdione structure, an iminooxadiazinedione structure, an isocyanurate structure, a urea structure, a urethane structure, and a biuret structure. Above all, it is preferable to have at least one structure selected from the group consisting of a urethane structure, an allophanate structure, a biuret structure, a urea structure, and an isocyanurate group.

Any of these aliphatic diisocyanates and alicyclic diisocyanates may be used alone, or two or more kinds of aliphatic diisocyanates and alicyclic diisocyanates may be used in combination.

<Polycaprolactone polyol (A2)>
The polycaprolactone polyol is not particularly limited, but specifically, it can be obtained by ring-opening polymerization in the presence of a catalyst using ε-caprolactone as a divalent or higher valent, preferably a trivalent alcohol as an initiator. Such an initiator is not particularly limited, but specifically, a dihydric alcohol such as ethylene glycol, propylene glycol, 1,3-butylene glycol, neopentylbricol; or a trihydric alcohol such as trimethylolpropane or glycerin. Alcohol or the like is used. In terms of obtaining a low-viscosity polyisocyanate, a polycaprolactone polyol having a branch is preferable. Such polycaprolactone polyols can be obtained by using a trihydric or higher alcohol as an initiator.

The catalyst is not particularly limited, but specifically, organic titanium compounds such as tetrabutyl titanate, tetrapropyl titanate, and tetraethyl titanate; tin octylate, dibutyltin oxide, dibutyltin laurate, stannous chloride, and bromide. A tin compound such as arsenic is used.

The ring-opening polymerization of ε-caprolactone is not particularly limited, but specifically, the molar ratio of ε-caprolactone to the above-mentioned initiator is set so as to have a desired molecular weight under a nitrogen gas atmosphere, and further, ε- It can be carried out by adding a catalyst of 0.1% by mass or more and 100% by mass or less to caprolactone and reacting at a temperature of 150 ° C. or more and 200 ° C. or less for 4 hours or more and 10 hours or less.

In polyisocyanate, a urethane group is formed by the reaction between the hydroxyl group of polycaprolactone polyol (A2) and the isocyanate group of diisocyanate.

The average number of hydroxyl group functional groups of the polycaprolactone polyol (A2) is preferably 2.0 or more and 8.0 or less, more preferably 2 or more and 6 or less, further preferably 2 or more and 5 or less, and particularly preferably 3. The average number of hydroxyl group functional groups of the polycaprolactone polyol (A2) referred to here is the number of hydroxyl groups present in one molecule of the polycaprolactone polyol (A2).

The number average molecular weight of the polycaprolactone polyol (A2) is preferably 500 or more and 1500 or less, more preferably 600 or more and 1400 or less, further preferably 700 or more and 1300 or less, and particularly preferably 850 or more and 1250 or less.
When the number average molecular weight of the polycaprolactone polyol (A2) is within the above range, the obtained coating film is more excellent in flexibility at low temperature and normal temperature. The number average molecular weight Mn of the polycaprolactone polyol (A2) is, for example, a polystyrene-based number average molecular weight measured by gel permeation chromatography (GPC).

Examples of commercially available polycaprolactone polyols include the trade names "Plaxel 305" (number average molecular weight 550), "Plaxel 308" (number average molecular weight 850), and "Pluxel 309" (number average molecular weight 900) manufactured by Daicel. , "Plaxel 312" (number average molecular weight 1250), "Plaxel 205" (number average molecular weight 530), "Plaxel 210" (number average molecular weight 1000); trade name "Polylite OD-X-2735" manufactured by DIC Co., Ltd. (Number average molecular weight 500), "Polylite OD-X-2586" (number average molecular weight 850), "Polylite OD-X-2588" (number average molecular weight 1250) and the like can be mentioned.

<Polyether polyol (B2)>
The polyether polyol (B2) contains polypropylene glycol (PPG, also referred to as polyoxypropylene polyol).
The content of PPG with respect to 100 parts by mass of the polyether polyol (B2) in the polyisocyanate composition 2 of the present embodiment is 20 parts by mass or more, preferably 40 parts by mass or more, more preferably 50 parts by mass or more, 55. More than parts by mass is more preferable, 60 parts by mass is particularly preferable, and 100 parts by mass is most preferable. When the content of PPG is at least the above lower limit value, the compatibility with the main agent in a low temperature environment can be improved.

The polypropylene glycol is not particularly limited, but specifically, polyoxypropylene diol or triol; a so-called pluronic (registered trademark) type polyoxypropylene diol obtained by addition-polymerizing ethylene oxide at the end of polyoxypropylene diol or triol. Alternatively, triol; polyoxypropylene polyoxyethylene polymer diol, triol, or the like can be mentioned. Among these, the Pluronic (registered trademark) type polyoxypropylene diol or triol is preferable because it has excellent reactivity with diisocyanate.

Examples of the method for producing polypropylene glycol include a method in which propylene oxide, if necessary, ethylene oxide or the like is added alone or as a mixture to an initiator and a catalyst. The initiator is not particularly limited, and specific examples thereof include polyhydric alcohols, polyhydric phenols, polyamines, alkanolamines, and mixtures thereof, and more specifically, ethylene glycol, diethylene glycol, and propylene glycol. Dihydric alcohols such as dipropylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, bisphenol A; trihydric alcohols such as glycerin and trimethylolpropane; diamines such as ethylenediamine; and mixtures thereof. Can be mentioned. The catalyst is not particularly limited, but specifically, hydroxides such as lithium, sodium and potassium; strongly basic catalysts such as alcoholate and alkylamine; metal porphyrin, complex metal cyan compound complex, metal and 3 Examples thereof include a complex with a chelating agent having a coordinator or higher, and a complex metal complex such as a zinc hexacyanocobalate complex. In addition, a method of dehydrating and condensing a polyhydric alcohol to obtain polypropylene glycol and the like can be mentioned.

As commercially available polypropylene glycols, the trade name "Exenol 510" (terminal EO addition type polyoxypropylene diol, number average molecular weight 4000) and "Exenol 840" (terminal EO addition type polyoxypropylene) manufactured by Asahi Glass Co., Ltd. are available. Triol, number average molecular weight 6500), "Exenol 1020" (terminal EO addition type polyoxypropylene diol, number average molecular weight 1000), "Exenol 2020" (terminal EO addition type polyoxypropylene diol, number average molecular weight 2000), etc. Can be mentioned.

The polyether polyol (B2) can contain other polyether polyols in addition to polypropylene glycol.
The other polyether polyol is not particularly limited, but for example, an alkali metal hydroxide or a strongly basic catalyst is used to add the alkylene oxide alone or the mixture to the polyhydric alcohol alone or the mixture. Examples thereof include a polyether polyol obtained by reacting a polyamine compound with an alkylene oxide, and a so-called polymer polyol obtained by polymerizing acrylamide or the like using the above-mentioned polyether as a medium.
Examples of the alkali metal include lithium, sodium, potassium and the like. Examples of the strongly basic catalyst include alcoholates, alkylamines and the like.
The polyhydric alcohol is not particularly limited, and examples thereof include at least one polyhydric alcohol selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, neopentyl glycol, trimethylolpropane, and glycerin.
Examples of the alkylene oxide include ethylene oxide, butylene oxide, cyclohexene oxide, styrene oxide and the like.
Examples of the polyamine compound include ethylenediamines.

Among them, as the other polyether polyol, polytetramethylene ether glycol (also referred to as PTMG or polyoxytetramethylene polyol) is preferable.

Polytetramethylene ether glycol is produced by cationic polymerization of tetrahydrofuran using a catalyst. The catalyst to be used is not particularly limited, but specifically, acetic anhydride-perchloric acid, fluorosulfonic acid, fuming sulfuric acid and the like are used. For example, the production of polyoxytetremethylene glycol is not particularly limited, but specifically, a fluorosulfonic acid of about 1% by mass or more and 30% by mass or less is usually added to the raw material tetrahydrofuran to 5 ° C. or more and 65% by mass. It can be carried out under the condition that the reaction is carried out at a temperature of ° C. or lower for several minutes or more and several tens of hours or less. Further, it can be obtained by adding butylene oxide using a polyhydric alcohol or the like as an initiator and a strong basic catalyst or the like as in the above-mentioned method for producing polypropylene glycol. Further, the molecular weight of the produced polytetramethylene ether glycol is adjusted by changing the polymerization temperature, the polymerization time, the amount of the catalyst used, and the like.

Examples of commercially available polytetramethylene ether glycols include trade names "PTMG1000" (number average molecular weight 1000), "PTMG2000" (number average molecular weight 2000), and "PTMG3000" (number average molecular weight 2000) manufactured by Mitsubishi Chemical Corporation. 2900), "PTMG4000" (number average molecular weight 4000) and the like.

In the polyether polyol (B2), the mass ratio of polytetramethylene ether glycol to polypropylene glycol (mass ratio of PTMG / PPG) is preferably 0/100 or more and 80/20 or less, and more preferably 0/100 or more and 60/40 or less. , 0/100 or more and 50/50 or less is more preferable, and 0/100 or more and 45/55 or less is particularly preferable. When the mass ratio of PTMG / PPG is within the above range, the compatibility with the main agent in a low temperature environment can be improved.

The number average molecular weight of the polyether polyol (B2) is preferably 1000 or more and 7,000 or less, more preferably 2000 or more and 7,000 or less, further preferably 3000 or more and 6700 or less, and 4000 or more and 6500 or less. It is particularly preferable to have.
When the number average molecular weight of the polyether polyol (B2) is within the above range, the obtained coating film is more excellent in flexibility at low temperature and normal temperature. The number average molecular weight Mn of the polyether polyol (B2) is, for example, a polystyrene-based number average molecular weight measured by GPC. When two or more kinds of polyether polyols (B2) are mixed and used, the number average molecular weight of the mixture is calculated.

In the polyisocyanate composition 2 of the present embodiment, the mass ratio of the polycaprolactone polyol (A2) to the polyether polyol (B2) (mass ratio of (A2) / (B2)) is 10/90 or more and 90/10 or less. It is preferable, 15/85 or more and 85/15 or less is more preferable, and 18/82 or more and 83/17 or less is further preferable.
When the mass ratio of (A2) / (B2) is at least the above lower limit value, the compatibility with the main agent in a low temperature environment can be improved. On the other hand, when it is not more than the above upper limit value, a coating film having more excellent flexibility at low temperature and normal temperature can be obtained.
The mass ratio of (A2) / (B2) can be calculated from, for example, the blending amount of each polyol.

<Manufacturing method of polyisocyanate composition 2>
The polyisocyanate is obtained by reacting the above diisocyanate with a polycaprolactone polyol (A2) and a polyether polyol (B2). Hereinafter, the polycaprolactone polyol (A2) and the polyether polyol (B2) may be collectively referred to as a polyol.

The polycaprolactone polyol (A2) and the polyether polyol (B2) can be used alone or as a mixture, respectively. When used as a mixture, it may be mixed before reacting with diisocyanate, or each polyol may be independently reacted with diisocyanate to form polyisocyanate and then mixed.
That is, as a method for producing the polyisocyanate composition 2, for example, a method of simultaneously reacting a diisocyanate with a polycaprolactone polyol (A2) and a polyether polyol (B2) to obtain a polyisocyanate composition 2; A method for obtaining a polyisocyanate composition 2 by mixing a reaction with a polycaprolactone polyol (A2), a diisocyanate and a reaction with a polyether polyol (B2); a diisocyanate and a polycaprolactone polyol ( Examples thereof include a method of reacting with A2) or a polyether polyol (B2) and then further reacting with the remaining polyol to obtain a polyisocyanate composition 2.

The amount of the polycaprolactone polyol (A2) and the polyether polyol (B2) is preferably blended so that the mass ratio of the polycaprolactone polyol (A2) to the polyether polyol (B2) is within the above range.

The reaction between the polyol and diisocyanate is performed as follows. The reaction temperature is usually room temperature (about 23 ° C.) or higher and 200 ° C. or lower, preferably 80 ° C. or higher and 120 ° C. or lower. If the reaction temperature is at least the above lower limit, the reaction time will be shorter, while if it is at least the above upper limit, the increase in viscosity of the polyisocyanate due to an undesired side reaction can be further avoided, and the resulting polyisocyanate will be colored. It can be avoided more.

At the time of the reaction, the molar ratio of the isocyanate group of the diisocyanate to the hydroxyl group of the polycaprolactone polyol (A2) and the polyether polyol (B2) (the molar ratio of the hydroxyl group / isocyanate group) is preferably 2 or more and 10 or less, preferably 3 or more and 9 or less. Is more preferable, and 4 or more and 8 or less are further preferable. When the molar ratio of the hydroxyl group / isocyanate group is at least the above lower limit value, it is possible to further avoid an increase in the viscosity of the polyisocyanate due to the sequential addition reaction between the diisocyanate and the polyol. On the other hand, when it is not more than the above upper limit value, the productivity becomes better.

At the end of the reaction, the unreacted diisocyanate in the reaction mixture is recovered by a known method such as a thin film distillation apparatus or solvent extraction. If the residual amount of unreacted diisocyanate is small, the odor, toxicity, irritation and the like caused by diisocyanate during heat curing can be further avoided.

<Physical characteristics of polyisocyanate composition 2>
The isocyanate group content (NCO group content) of the polyisocyanate composition 2 of the present embodiment is 3% by mass or more with respect to the total mass of the polyisocyanate composition 2 in a state where it does not substantially contain a solvent or diisocyanate. It is preferably 8% by mass or less, more preferably 3.1% by mass or more and 7.5% by mass or less, and further preferably 3.3% by mass or more and 7.3% by mass or less.
The NCO group content can be determined, for example, by reacting the isocyanate group of the polyisocyanate composition 2 with an excess amine (dibutylamine or the like) and back-titrating the remaining amine with an acid such as hydrochloric acid.

≪Resin composition≫
The resin composition of the present embodiment contains the above-mentioned polyisocyanate composition 2 as a curing agent component and a polyol as a main agent component.

By containing the polyisocyanate composition 2 as a curing agent component in the resin composition of the present embodiment, a coating film having excellent flexibility at a low temperature of about −10 ° C. and a normal temperature of about 23 ° C. can be obtained.

The resin composition of the present embodiment is, for example, a building paint, an automobile paint, an automobile repair paint, a plastic paint, an adhesive, an adhesive, a building material, a household water-based paint, other coating agents, a sealing agent, an ink, and the like. It can be used for casting materials, elastomers, foams, plastic raw materials, fiber treatment agents, etc.
Above all, the resin composition of the present embodiment is preferably used as a pressure-sensitive adhesive composition because it has good flexibility at low temperature and normal temperature, especially when it is used as a coating film.

Next, the details of each component contained in the resin composition of the present embodiment will be described below.

<Polyol>
Specific examples of the polyol include an aliphatic hydrocarbon polyol, a polyether polyol, a polyester polyol, an epoxy resin, a fluorine-containing polyol, and an acrylic polyol.
Above all, the polyol is preferably an acrylic polyol.

[Acrylic polyol]
The acrylic polyol may, for example, polymerize a polymerizable monomer having one or more active hydrogens in one molecule, or may have a polymerizable monomer having one or more active hydrogens in one molecule, if necessary. It is obtained by copolymerizing the polymerizable monomer with another copolymerizable monomer.

Examples of the polymerizable monomer having one or more active hydrogens in one molecule include those shown in the following (i) to (iii). These may be used alone or in combination of two or more.
(I) Acrylic acid ester having active hydrogen such as -2-hydroxyethyl acrylate, -2-hydroxypropyl acrylate, and -2-hydroxybutyl acrylate.
(Ii) A methacrylic acid ester having active hydrogen such as -2-hydroxyethyl methacrylate, -2-hydroxypropyl methacrylate, and -2-hydroxybutyl methacrylate.
(Iii) A (meth) acrylic acid ester having a polyvalent active hydrogen such as acrylic acid monoester or methacrylic acid monoester of glycerin, acrylic acid monoester or methacrylic acid monoester of trimethylolpropane.

Examples of other monomers copolymerizable with the polymerizable monomer include those shown in the following (i) to (v). These may be used alone or in combination of two or more.
(I) Acrylic acid esters such as methyl acrylate, ethyl acrylate, isopropyl acrylate, -n-butyl acrylate, and -2-ethylhexyl acrylate.
(Ii) Methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, -n-butyl methacrylate, isobutyl methacrylate, -n-hexyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, and glycidyl methacrylate.
(Iii) Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid. (Iv) Unsaturated amides such as acrylamide, N-methylolacrylamide, and diacetoneacrylamide.
(V) Styrene, vinyltoluene, vinyl acetate, acrylonitrile, etc.

Further, an acrylic polyol obtained by copolymerizing a polymerizable ultraviolet stable monomer disclosed in Reference 3 (Japanese Patent Laid-Open No. 1-261409) and Reference Document 4 (Japanese Patent Laid-Open No. 3-006273). And so on.

For example, the above monomer component is solution-polymerized in the presence of a known radical polymerization initiator such as a peroxide or an azo compound, and if necessary, diluted with an organic solvent or the like to obtain an acrylic polyol. Can be done.

When an aqueous-based base acrylic polyol is obtained, it can be produced by a known method such as solution polymerization of an olefinically unsaturated compound and conversion to an aqueous layer or emulsion polymerization. In that case, water solubility or water dispersibility can be imparted by neutralizing an acidic portion such as a carboxylic acid-containing monomer such as acrylic acid or methacrylic acid or a sulfonic acid-containing monomer with an amine or ammonia.

[Isocyanate group / hydroxyl group]
The molar ratio of isocyanate groups (isocyanate group / hydroxyl group molar ratio) of the polyisocyanate composition 2 to the hydroxyl groups of the polyol contained in the resin composition of the present embodiment is determined by the required physical properties of the resin film, but is usually used. , 0.01 or more and 22.5 or less.

<Other ingredients>
The resin composition of the present embodiment may further contain other additives.
Examples of other additives include curing agents other than the polyisocyanate composition 2 capable of reacting with polyols, curing catalysts, solvents, pigments (extension pigments, coloring pigments, metallic pigments, etc.), photopolymerization initiators, and ultraviolet absorbers. , Light stabilizers, radical stabilizers, anti-yellowing agents that suppress coloration during the baking process, coating surface adjusters, flow adjusters, pigment dispersants, antifoaming agents, thickeners, film-forming aids, etc. ..

<Manufacturing method of resin composition>
The resin composition of the present embodiment can be produced by a conventionally known method.
When the resin composition of the present embodiment is a pressure-sensitive adhesive composition, for example, a general mixer such as a Banbury mixer, a single-screw screw extruder, a twin-screw screw extruder, a conider, or a multi-screw screw extruder is used. A method of melt-kneading, a method of dissolving or dispersing and mixing each component, a method of coating on a base film with a coater or the like, and then a method of removing the solvent by heating is used.

The resin composition of the present embodiment may be foamed in order to reduce the weight, make it flexible, and improve the adhesion. Examples of the foaming method include a chemical method, a physical method, and the use of a heat-expandable microballoon. Bubbles can be distributed inside the material by adding a chemical foaming agent such as an inorganic foaming agent or an organic foaming agent, a physical foaming agent, or the like, or by adding a heat-expandable microballoon.

When the resin composition of the present embodiment is an adhesive composition, a tackifier resin may be added to adjust the adhesive force and the cohesive force. Examples of the tackifying resin include a rosin-based tackifier resin, a terpene-based tackifier resin, a petroleum-based tackifier resin, and a styrene-based tackifier resin. These tackifier resins may be used alone or in combination of two or more. Further, the softening point of the tackifier resin is preferably 90 ° C. or higher and 160 ° C. or lower.

Hereinafter, the present embodiment will be described in more detail based on Examples and Comparative Examples, but the present embodiment is not limited to the following Examples.

<Test items>
The polyisocyanate compositions produced in Examples and Comparative Examples were measured and evaluated for their physical properties according to the methods shown below.

[Physical characteristics 1] (Isocyanate group content)
First, 2 g or more and 3 g or less of the measurement sample were precisely weighed in a flask (Wg). Then, 20 mL of toluene was added to dissolve the measurement sample. Then, 20 mL of a toluene solution of 2N-butylamine was added, and after mixing, the mixture was allowed to stand at room temperature for 15 minutes. Then 70 mL of isopropyl alcohol was added and mixed. This solution was then titrated into an indicator with a 1N hydrochloric acid solution (Factor F). The obtained titration value was V2 mL. Then, without the polyisocyanate sample, the obtained titration value was set to V1 ml. Next, the isocyanate group content (NCO%) (mass%) of the polyisocyanate composition was calculated from the following formula.

Isocyanate group content (% by mass) = (V1-V2) x F x 42 / (W x 1000) x 100

[Physical characteristics 2] (number average molecular weight and weight average molecular weight)
The number average molecular weight and the weight average molecular weight are the number average molecular weight and the weight average molecular weight based on polystyrene by gel permeation chromatography (GPC) measurement using the following apparatus.

(Measurement condition)
Equipment: HLC-802A manufactured by Tosoh Corporation
Column: Tosoh Corporation, G1000HXL x 1 G2000HXL x 1 G3000HXL x 1 Carrier: Tetrahydrofuran Detection method: Differential refractometer

[Physical characteristics 3] (Average number of isocyanate functional groups)
The average number of isocyanate functional groups (average number of NCOs) of the polyisocyanate composition was calculated by the following formula. In the formula, "Mn" means a number average molecular weight, and the value measured in the above "Physical characteristics 2" was used. As "NCO%", the value calculated in the above "Physical characteristics 1" was used.

Average number of isocyanate functional groups = (Mn x NCO% x 0.01) / 42

[Physical characteristics 4] (Glass transition temperature Tg)
The glass transition temperature of the acrylic polyol and the crosslinkable functional group-containing polymer is the differential scanning calorimetry of the organic solvent and water in the acrylic polyol solution or the crosslinkable functional group-containing polymer solution, which are dried under reduced pressure and then vacuum-dried. The value measured at a heating rate of 5 ° C./min using a DSC) measuring device was used as the glass transition temperature.

[Preparation of cured film of polyisocyanate composition]
Each polyisocyanate composition is coated on a release film using an applicator, stored at 23 ° C. in a 65% humidity environment for 168 hours, and further heated at 50 ° C. for 24 hours to form a cured film having a film thickness of 40 μm. Obtained.

[Evaluation 1] (Flexibility of cured film)
The König hardness (times) of the cured film was measured in a 23 ° C. environment with a König hardness tester (Pendulum hardness tester manufactured by BYK Gardener). Those having a König hardness of 60 times or less were evaluated as having low hardness and good flexibility.

[Preparation of coating film]
Each polyisocyanate composition, a polyol, and an acrylic polyol for producing a coating composition were mixed to obtain a coating composition. Each of the obtained coating compositions was applied onto a release film using an applicator, cured at 90 ° C. for 30 minutes, and stored at 23 ° C. in a 65% humidity environment for 168 hours to obtain a coating film.

[Evaluation 2] (Stress at elongation rate and elongation rate of 140%)
For the obtained coating film, a test piece having a width of 10 mm and a length of 100 mm was set in a tensile tester so that the gripping tool distance was 20 mm, and a tensile test was performed at a speed of 20 mm / min. The stress at the time was measured. Those having an elongation rate of 50% or more and a stress of 28 MPa or less at an elongation rate of 140% were evaluated as having good stress at an elongation rate and an elongation rate of 140%, respectively.

[Preparation of Adhesive Composition X]
0.5 parts by mass of each polyisocyanate composition (1.0 part by mass for the polyisocyanate compositions PA1-a5 and PA1-a11) and ethyl acetate were added to 100 parts by mass of the acrylic polymer OH1. Then, a pressure-sensitive adhesive composition X having a solid content of 25% by mass was prepared.

[Preparation of Adhesive Composition Y]
To 100 parts by mass of the acrylic polymer OH2, 3 parts by mass of each polyisocyanate composition and ethyl acetate were added to prepare a pressure-sensitive adhesive composition Y having a solid content of 25% by mass.

[Preparation of Adhesive Sheet 1] (Preparation of Adhesive Sheet for 180 Degree Peel Adhesive Strength Measurement)
The pressure-sensitive adhesive composition X or the pressure-sensitive adhesive composition Y was coated on a 25 μm-thick polyethylene terephthalate (PET) film with an applicator so that the thickness after drying was 50 μm, and dried at 130 ° C. for 3 minutes. Then, it was stored in the environment of 23 ° C. and 50% RH for 7 days to obtain a pressure-sensitive adhesive sheet for measuring 180-degree peel adhesive strength.

[Evaluation 3] (Adhesiveness and cohesiveness)
Using the adhesive sheet obtained in the above "Preparation of adhesive sheet 1", using a steel plate of SUS304BA as an adherend, a 2 kg roller is reciprocated once to press the test piece against the steel plate, and the test piece is cured at 23 ° C. for 30 minutes. After that, the peel adhesive strength of 180 degrees was measured at a speed of 300 mm / min using a tensile tester. Those having 0.05 N / 20 mm or more were evaluated as having good adhesiveness.
In addition, those in which the adhesive layer did not remain on the adherend after peeling were evaluated as having good cohesive force (in the table: ◯). In addition, on the surface of the adherend, those with a slight adhesive residue of 5% or less of the area of the pasted portion are Δ, and those with an area larger than 5% and smaller than 20 are Δ ○, 20%. Those with adhesive residue in the above area were marked with x.

[Preparation of adhesive sheet 2] (Preparation of adhesive sheet for gel fraction measurement)
The pressure-sensitive adhesive composition X or the pressure-sensitive adhesive composition Y was applied to a peel-treated PET film having a thickness of 38 μm by an applicator so that the thickness after drying was 50 μm, and dried at 130 ° C. for 3 minutes. Then, it was stored in the environment of 23 ° C. and 50% RH for 7 days to obtain an adhesive sheet for measuring the gel fraction.

[Evaluation 4] (curability)
About 0.1 g or more and 0.2 g or less of the adhesive sheet obtained in the above "Preparation of adhesive sheet 2" is collected, wrapped in a mesh-like sheet, immersed in ethyl acetate for 1 week, and then dried at 120 ° C. for 2 hours. did. Then, the gel fraction (% by mass) was calculated using the following formula. Those having a gel fraction of 20% by mass or more were evaluated as having good curability.

(Gel fraction) = (Sample mass after drying) / (Sample mass before adding ethyl acetate) x 100

[Preparation of adhesive sheet 3] (Preparation of adhesive sheet for measuring haze value)
The pressure-sensitive adhesive layer X or the pressure-sensitive adhesive composition Y is coated on a polyethylene terephthalate film having a thickness of 38 μm and dried at 130 ° C. for 3 minutes and cured to remove the pressure-sensitive adhesive layer having a thickness of 50 μm. After peeling from the treated polyethylene terephthalate film, it was bonded onto glass having a haze value of 0.1% to obtain an adhesive sheet for measuring the haze value.

[Evaluation 5] (Transparency)
The haze of the adhesive sheet obtained in the above "Preparation of adhesive sheet 3" was measured using a haze meter (HMG-2DP) manufactured by Suga Test Instruments. Those with a haze value of 2% or less were evaluated as having good transparency.

[Preparation of resin composition]
Each polyisocyanate composition and an acrylic polyol (manufactured by Allnex, trade name "Setalux 1152") are mixed so that the molar ratio of isocyanate groups to hydroxyl groups is 1.0, and the solid content becomes 50% by mass. Diluted with butyl acetate. Next, a tin catalyst (manufactured by Nitto Kasei Co., Ltd., trade name "Neostan U-100") was further mixed with the diluted solution in an amount of 300 mass ppm with respect to the solid content to obtain each resin composition.

[Evaluation 6] (Compatibility with the main agent)
Immediately after preparation, each resin composition was kept in an environment of −10 ° C. for 5 days. The state of the coating liquid was visually observed and evaluated according to the following evaluation criteria.

(Evaluation criteria)
⊚: Transparent and uniform △: Partially turbid ×: Overall turbidity

[Preparation of coating film]
Each resin composition was applied onto a polypropylene plate so as to have a film thickness of 30 μm, and dried by heating at 120 ° C. for 30 minutes. Then, each coating film was prepared by drying at 23 ° C. and 50% humidity environment for 1 day.

[Evaluation 7] (Low temperature breaking elongation)
The prepared coating film was cut into strips to prepare test pieces. Next, it was mounted on a tensile tester (Tensilon universal tester) so as to have a length of 20 mm and a width of 10 mm, and a test was carried out at a tensile speed of 20 mm / min at a test temperature of -10 ° C. .. The fractured elongation was evaluated according to the following evaluation criteria.

(Evaluation criteria)
⊚: Breaking elongation 150% or more ○: Breaking elongation 100% or more and less than 150% ×: Breaking elongation less than 100%

[Evaluation 8] (Low temperature low stress (stress at 20% elongation))
The prepared coating film was cut into strips to prepare test pieces. Next, it was mounted on a tensile tester (Tensilon universal tester) so as to have a length of 20 mm and a width of 10 mm, and the test was carried out at a test temperature of −10 ° C. and a tensile speed of 20 mm / min. The stress values at an elongation of 20% were evaluated according to the following evaluation criteria.

(Evaluation criteria)
⊚: less than 10 MPa ○: 10 MPa or more and less than 30 MPa ×: 30 MPa or more

[Evaluation 9] (Low stress at room temperature (stress at elongation 75%))
The prepared coating film was cut into strips to prepare test pieces. Next, it was mounted on a tensile tester (Tensilon universal tester) so as to have a length of 20 mm and a width of 10 mm, and the test was carried out at a test temperature of 23 ° C. and a tensile speed of 20 mm / min. The stress values at an elongation of 75% were evaluated according to the following evaluation criteria.

(Evaluation criteria)
⊚: less than 2 MPa ○: 2 MPa or more and less than 5 MPa ×: 5 MPa or more

<Manufacturing of acrylic polyol>
[Synthesis Example 1-1] (Manufacturing of Acrylic Polyol for Fabrication of Paint Composition)
29 parts by mass of propylene glycol monomethyl ether was charged in a four-necked flask equipped with a stirrer, a thermometer, a cooling tube, and a nitrogen gas inlet, and the temperature was raised to 112 ° C. under ventilation of nitrogen gas. After reaching 112 ° C., the aeration of nitrogen gas was stopped, 2-hydroxyethyl methacrylate: 22.3 parts by mass, methyl methacrylate: 8.0 parts by mass, butyl acrylate: 26.1 parts by mass, styrene: 42.3 parts by mass. A mixture consisting of parts, acrylic acid: 1.3 parts by mass, and 2,2'-azobis (isobutyronitrile): 2 parts by mass was added dropwise over 5 hours. Then, the mixture was stirred at 115 ° C. while flowing nitrogen gas for 3 hours, cooled to 60 ° C., and a butyl acetate solution was added to obtain a solution of an acrylic polyol for preparing a coating composition having a solid content of 60% by mass. The acrylic polyol for producing a coating composition had a glass transition temperature Tg of 29.1 ° C., a hydroxyl value with respect to the resin solid content of 139 mgKOH / g, and a weight ^average molecular weight Mw of 2.56 × 104.

<Synthesis of crosslinkable functional group-containing polymer>
[Synthesis Example 1-2] (Synthesis of acrylic polymer OH1)
In a four-necked flask equipped with a stirrer, a thermometer, a nitrogen gas introduction tube and a cooling tube, 97 parts by mass of 2-ethylhexyl acrylate (2EHA) and 3 parts by mass of 4-hydroxybutyl acrylate (4-HBA) were added. It was charged, and 145 parts by mass of ethyl acetate was charged as a solvent. Next, 0.15 parts by mass of 2,2'-azobisisobutyronitrile (AIBN) was added as a polymerization initiator while stirring under a nitrogen gas atmosphere, and the reaction was carried out at 63 ° C. for 8 hours. After the reaction, the mixture was cooled to obtain an acrylic polymer OH1 having a solid content concentration of 41.8% by mass. The glass transition temperature measured by removing the solvent of the acrylic polymer ^OH1 was −69 ° C., and the weight average molecular weight was 8.3 × 105.

[Synthesis Example 1-3] (Synthesis of acrylic polymer OH2)
97 parts by mass of n-butyl acrylate (BA) and 3 parts by mass of 4-hydroxybutyl acrylate (4-HBA) are put into a four-necked flask equipped with a stirrer, a thermometer, a nitrogen gas introduction tube and a cooling tube. , 145 parts by mass of ethyl acetate was added as a solvent. Then, while stirring under a nitrogen gas atmosphere, 0.15 parts by mass of 2,2'-azobisisobutyronitrile (AIBN) was added as a polymerization initiator, and the reaction was carried out at 63 ° C. for 8 hours. After the reaction, the mixture was cooled to obtain an acrylic polymer OH2 having a solid content concentration of 41.6% by mass. The glass transition temperature measured by removing the solvent of the acrylic polymer OH2 was −54 ° C., and the weight ^average molecular weight was 7.8 × 105.

<Manufacturing of Polyisocyanate Composition 1>
[Example 1-1] (Production of polyisocyanate composition PA1-a1)
A four-necked flask equipped with a thermometer, a stirring blade, and a reflux cooling tube is charged with 100 parts by mass of HDI under a nitrogen stream, and is referred to as a bifunctional polycaprolactone polyol A1 (hereinafter referred to as “polycaprolactone A1” or simply “A1”). (In some cases) (manufactured by Daicel, trade name "Plaxel 220", number average molecular weight 2000) 1.8 parts by mass, and trifunctional polycaprolactone polyol B1 (hereinafter referred to as "polyol B1" or simply "B1"). (In some cases) (manufactured by Daicel, trade name "Plaxel 308", number average molecular weight 850) 33 parts by mass (amount in which the molar ratio of the isocyanate group of HDI to the hydroxyl group of polyol A1 and polyol B1 is 10.2) is stirred. While maintaining the temperature inside the reactor at 95 ° C., the temperature was maintained for 100 minutes. The reaction was stopped when the yield reached 41% by mass. After filtering the reaction solution, unreacted HDI was removed by a thin film distillation apparatus to obtain a polyisocyanate composition PA1-a1.

[Examples 1-2 to 1-13 and Comparative Examples 1-2 to 1-3] (Production of polyisocyanate compositions PA1-a2-PA1-a13 and PA1-b2-PA1-b3)
Each polyisocyanate composition was obtained by the same method as in Example 1-1 except that the compositions were as shown in Tables 1-1 to 1-2 and 1-4.

[Example 1-14] (Production of polyisocyanate composition PA1-a14)
The polyisocyanate composition PA1-a3: 100 parts by mass, methoxypolyethylene glycol (MPG-) obtained in Example 1-3 was placed in a four-necked flask equipped with a thermometer, a stirring blade and a reflux cooling tube under a nitrogen stream. 081, polyethylene oxide repeating unit: 15 pieces, manufactured by Nippon Emulsifier Co., Ltd.): 0.6 parts by mass, and 2-ethylhexyl acid phosphate (JP-508T, manufactured by Johoku Chemical Industry Co., Ltd.): 0.08 parts by mass are mixed. , 95 ° C. for 2 hours to obtain a polyisocyanate composition PA1-a14.

[Examples 1-15 to 1-18] (Production of polyisocyanate compositions PA1-a15 to PA1-a18, PA1-a20 to PA1-a21)
Each polyisocyanate composition was obtained by the same method as in Example 1-1 except that the composition was as shown in Table 1-3. For PA1-a20 and PA1-a21, the reaction was stopped when the yields reached 44% and 48%, respectively. Others were treated in the same manner as in Example 1-1.
[Example 1-19] (Production of polyisocyanate composition PA1-a19)
A four-necked flask equipped with a thermometer, a stirring blade, and a reflux cooling tube is charged with 100 parts by mass of HDI under a nitrogen stream, and is referred to as a bifunctional polycaprolactone polyol A4 (hereinafter referred to as "polyol A4" or simply "A4"). (In some cases) (manufactured by Daicel, trade name "Plaxel 220CPT", number average molecular weight 2000) 10 parts by mass, and trifunctional polycaprolactone polyol B1 (hereinafter, may be referred to as "polyol B1" or simply "B1"). (Amount of HDI isocyanate group molar ratio to 9.8 to the hydroxyl group of polyol A1 and polyol B1) with 32 parts by mass (manufactured by Daicel, trade name "Plaxel 308", number average molecular weight 850) while stirring. The temperature inside the reactor was maintained at 95 ° C. and maintained for 100 minutes. The reaction was stopped when the yield reached 41% by mass. After filtering the reaction solution, unreacted HDI was removed by a thin film distillation apparatus to obtain a polyisocyanate composition. A bifunctional polycaprolactone polyol A4 (manufactured by Daicel Co., Ltd., trade name "Plaxel 220CPT") with respect to 100 parts by mass of polyisocyanate obtained under a nitrogen stream in a four-necked flask equipped with a thermometer, stirring blade, and reflux cooling tube. , Number average molecular weight 2000) 3 parts by mass is mixed (NCO / OH = 24.4), 0.060 parts by mass of JP-508T is added, the temperature inside the reactor is maintained at 105 ° C. and maintained for 120 minutes, and the polyisocyanate is used. The composition PA1-a19 was obtained.

[Comparative Example 1-1] (Production of Polyisocyanate Composition PA1-b1)
In a four-necked flask equipped with a thermometer, a stirring blade and a reflux condenser, 100 parts by mass of HDI and 8.9 parts by mass of trimethylol propane were charged under a nitrogen stream, and the temperature inside the reactor under stirring was 75 ° C. Was held for 5 hours to carry out a urethanization reaction. After filtering the reaction solution, unreacted HDI was removed using a thin film evaporator to obtain a polyisocyanate composition PA1-b1 containing an isocyanurate-type polyisocyanate.

The physical characteristics of the polyisocyanate composition 1 obtained in Examples and Comparative Examples and the results of evaluation by the method described above are shown in Tables 1-1 to 1-4 below. In Comparative Example 1-1, when the stress at the elongation rate of 140% was measured, the elongation did not extend to 140%, the breaking point stress was 72 MPa, and the measurement was not possible. ".
Further, in Tables 1-1 to 1-4, each abbreviation means the following compounds.

(Polyol (A1))
A1-1: 2-functional polycaprolactone polyol, manufactured by Daicel, trade name "Plaxel 220", number average molecular weight 2000
A1-2: Bifunctional polycaprolactone polyol, manufactured by Daicel, trade name "Plaxel 230", number average molecular weight 3000
A1-3: Bifunctional polycaprolactone polyol, manufactured by Daicel, trade name "Plaxel 240", number average molecular weight 4000
A1-4: Bifunctional polycaprolactone polyol, manufactured by Daicel, trade name "Plaxel 220CPT", number average molecular weight 2000
A1'-1: Polytetramethylene ether glycol, manufactured by Mitsubishi Chemical Corporation, trade name "PTMG1000", number average molecular weight 1000
A1'-2: Polyether polyol, manufactured by AGC Inc., trade name "Exenol2020", number average molecular weight 2000, OH value 55.8 mg / KOH
A1'-3: Polyether polyol, manufactured by AGC Inc., trade name "Exenol 4030", number average molecular weight 4000, OH value 42 mg / KOH
A1'-4: Polycarbonate diol, manufactured by Asahi Kasei Corporation, trade name "T5652", number average molecular weight 2000, OH value 56.0 mg / KOH

(Polyol (B1))
B1-1: 3-functional polycaprolactone polyol, manufactured by Daicel, trade name "Plaxel 308", number average molecular weight 850
B1-2: Trifunctional polycaprolactone polyol, manufactured by Daicel, trade name "Plaxel 312", number average molecular weight 1250
B1-3: Trifunctional polycaprolactone polyol, manufactured by Daicel, trade name "Plaxel 305", number average molecular weight 550
B1'-1: Trimethylolpropane (TMP)

Polyisocyanate compositions PA1-a1 to PA1-a21 (Example 1-) derived from a diisocyanate and two types of polyols having a number average molecular weight within a specific numerical range and having a weight average molecular weight of 1400 or more. In 1 to 1-21), the hardness of the cured film is low and the flexibility is good, the elongation rate of the coating film and the stress at the elongation rate of 140% are good, and the adhesive sheet. It was excellent in adhesiveness, cohesive force, curability and transparency.

On the other hand, polyisocyanate compositions PA1-b1 to PA1-b2 (Comparative Examples 1-1 to 1-2), which are derived from diisocyanate and one kind of polyol or have a weight average molecular weight of less than 1400. Alternatively, a polyisocyanate composition PA1-b3 (Comparative Example 1-3) derived from a diisocyanate and two types of polyols having a number average molecular weight outside a specific numerical range and having a weight average molecular weight of less than 1400. However, it was not possible to obtain a product having good flexibility when used as a cured film and good adhesiveness, cohesiveness, curability and transparency when used as an adhesive sheet.
<Manufacturing of Polyisocyanate Composition 2>
[Example 2-1]
(Production of Polyisocyanate Composition PA2-a1)
The inside of a 4-necked flask equipped with a stirrer, a thermometer, a reflux cooling tube, a nitrogen blowing tube, and a dropping funnel is made into a nitrogen atmosphere, and HDI 1000 g and a trifunctional polycaprolactone polyol (manufactured by DIC Co., Ltd., trade name "OD-" X2588 ”, number average molecular weight 1250) 496.0 g was charged, and the temperature inside the reactor was maintained at 100 ° C. under stirring to proceed with the urethanization reaction. After filtering the reaction solution, unreacted HDI was removed using a thin film evaporator to obtain a polyisocyanate precursor. 100.0 g of the polyisocyanate precursor is charged in a flask, 57.0 g of polyoxypropylene diol (manufactured by AGC Co., Ltd., trade name "Excell 510", number average molecular weight 4000) is charged, and the temperature inside the reactor is set to 100 ° C. under stirring. It was retained and the urethanization reaction was allowed to proceed to obtain a polyisocyanate composition PA2-a1.

[Examples 2-2 to 2-6]
(Production of Polyisocyanate Compositions PA2-a2-PA2-a6)
Each polyisocyanate composition was obtained by the same method as in Example 2-1 except that the compositions shown in Table 2-1 were used.

[Example 2-7]
(Production of Polyisocyanate Composition PA2-a7)
The inside of a four-necked flask equipped with a stirrer, a thermometer, a reflux cooling tube, a nitrogen blowing tube, and a dropping funnel is made into a nitrogen atmosphere, and HDI 1000 g, a trifunctional polycaprolactone polyol (manufactured by DIC Co., Ltd., trade name "OD-X2735") , Number average molecular weight 500) 150.0 g, Polytetramethylene ether glycol (manufactured by Mitsubishi Chemical Corporation, trade name "PTMG1000", number average molecular weight 1000) 200.0 g, and polyoxypropylene diol (manufactured by AGC Co., Ltd., The product name "Excell 510", number average molecular weight 4000) 300.0 g was charged, and the temperature inside the reactor was maintained at 100 ° C. under stirring to proceed with the urethanization reaction. After filtering the reaction solution, unreacted HDI was removed using a thin film evaporator to obtain a polyisocyanate composition PA2-a6.

[Examples 2-8 and Comparative Examples 2-1 to 2-3]
(Production of Polyisocyanate Compositions PA2-a8 and PA2-b1 to PA2-b3)
Each polyisocyanate composition was obtained by the same method as in Example 2-7 except that the compositions shown in Table 2-2 were used.

Table 2-1 and Table 2-2 show the physical characteristics of each of the obtained polyisocyanate compositions and the evaluation results using the method described above.

In Table 2-1 and Table 2-2, each abbreviation indicates the following compound.

(Polycaprolactone polyol (A2))
A2: Polycaprolactone polyol OD-X-2735: DIC Corporation, trifunctional polycaprolactone polyol, number average molecular weight 500
OD-X-2586: Trifunctional polycaprolactone polyol manufactured by DIC Corporation, number average molecular weight 850
OD-X-2588: Trifunctional polycaprolactone polyol manufactured by DIC Corporation, number average molecular weight 1250

(Polyether polyol (B2))
B2-1: Polypropylene glycol Excelnol 510: Polyoxypropylene diol manufactured by AGC Inc., number average molecular weight 4000
Excelcol 840: AGC Inc., polyoxypropylene triol, number average molecular weight 6500
Excelnol 1020: manufactured by AGC Inc., polyoxypropylene diol, number average molecular weight 1000

B2-2: Other polyether polyols PTMG1000: Made by Mitsubishi Chemical Corporation, polytetramethylene ether glycol, number average molecular weight 1000

A polyisocyanate composition derived from a diisocyanate, a polycaprolactone polyol (A2), and a polyether polyol (B2), and containing 20 parts by mass or more of polypropylene glycol with respect to 100 parts by mass of the polyether polyol (B2). PA2-a1 to PA2-a8 (Examples 2-1 to 2-8) have good compatibility with the main agent in a low temperature environment of about -10 ° C, and are about -10 ° C when used as a coating film. It was excellent in breaking elongation at low temperature and low stress property at low temperature of about -10 ° C and normal temperature of about 23 ° C.

The polyisocyanate composition PA2-b1 (Comparative Example 2-1) derived from the diisocyanate and the polycaprolactone polyol (A2) has good compatibility with the main agent in a low temperature environment of about -10 ° C. However, when the coating film was used, the elongation at break at a low temperature of about −10 ° C. and the low stress property at a low temperature of about −10 ° C. and a normal temperature of about 23 ° C. were poor.
Further, the polyisocyanate composition PA2-b2 (Comparative Example 2-2) derived from the diisocyanate, the polycaprolactone polyol (A2), and the polyether polyol (B2) containing no polypropylene glycol was used as a coating film. The elongation at break at a low temperature of about -10 ° C and the low stress resistance at a low temperature of about -10 ° C and a normal temperature of about 23 ° C were within the permissible range, but under a low temperature environment of about -10 ° C. The compatibility with the main agent was poor.
Further, polypropylene derived from diisocyanate, polycaprolactone polyol (A2), and polyether polyol (B2), and less than 20 parts by mass (10 parts by mass) with respect to 100 parts by mass of the polyether polyol (B2). In the polyisocyanate composition PA2-b3 containing glycol (Comparative Example 2-3), the elongation at break at a low temperature of about -10 ° C when used as a coating film, and the elongation at break at a low temperature of about -10 ° C and about 23 ° C. The low stress property at room temperature was within the allowable range, but the compatibility with the main agent in a low temperature environment of about -10 ° C was poor.

According to the polyisocyanate composition 1 of the present embodiment, the adhesive sheet obtained by curing the polyisocyanate composition alone has good flexibility and is excellent in adhesiveness, cohesive force, curability and transparency. The polyisocyanate composition obtained can be provided.
Further, according to the polyisocyanate composition 2 of the present embodiment, the compatibility with the main agent in a low temperature environment of about −10 ° C. is good, and the low temperature of about −10 ° C. and 23 ° C. It is possible to provide a polyisocyanate composition having excellent flexibility at a normal temperature of about the same degree.

Claims

At least one diisocyanate selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, a bifunctional polyol (A1) having a number average molecular weight of 1500 or more, and a trifunctional or higher having a number average molecular weight of 500 or more. A polyisocyanate composition derived from a polyol (B1).
The molar ratio of the isocyanate group of the diisocyanate to the hydroxyl groups of the polyol (A1) and the polyol (B1) is 2 or more and 30 or less.
A polyisocyanate composition having a weight average molecular weight of 1400 or more.
The mass ratio of the polyol (B1) to the polyol (A1) is 0.1 / 99.9 or more and 99.9 / 0.1 or less, and
With respect to 100 parts by mass of the diisocyanate
The content of the polyol (A1) is 0.1 parts by mass or more and 250 parts by mass or less.
The polyisocyanate composition according to claim 1, wherein the content of the polyol (B1) is 1 part by mass or more and 190 parts by mass or less.
The polyisocyanate composition according to claim 1 or 2, wherein the polyisocyanate composition has an average number of isocyanate functional groups of 2 or more and 6 or less.
The polyisocyanate composition according to any one of claims 1 to 3, wherein the polyisocyanate composition has an isocyanate group content of 1% by mass or more and 10% by mass or less.
Any of claims 1 to 4, wherein the polyol (A1) and the polyol (B1) are at least one polyol selected from the group consisting of polyester polyols, polyether polyols, epoxy polyols, polyolefin polyols, and polycarbonate polyols. The polyisocyanate composition according to item 1.
The polyisocyanate composition according to any one of claims 1 to 5, wherein the polyol (A1) and the polyol (B1) are polyester polyols.
The polyisocyanate composition according to claim 6, wherein the polyol (A1) and the polyol (B1) are polycaprolactone polyols.
The polyisocyanate composition according to any one of claims 1 to 7 is formed after being coated on glass, stored at 23 ° C. in a 65% humidity environment for 168 hours, and further heated at 50 ° C. for 24 hours. A cured film with a film thickness of 40 μm,
A cured film having a König hardness of 60 times or less in an environment of 23 ° C.
The polyisocyanate composition according to any one of claims 1 to 7, has a glass transition temperature of 29.1 ° C., a hydroxyl value of 139 mgKOH / g, and a weight average molecular weight of 2.56 × 10 4 . A coating composition containing the acrylic polyol is cured at 90 ° C. for 30 minutes and stored at 23 ° C. in a 65% humidity environment for 168 hours to obtain a coating film having a film thickness of 40 μm.
The test piece having a width of 10 mm and a length of 100 mm of the coating film was set in a tensile tester so that the gripping tool distance was 20 mm, and the elongation rate in the tensile test measured at a speed of 20 mm / min was 50% or more. Moreover, the coating film has a stress of 28 MPa or less when the elongation rate is 140%.
A pressure-sensitive adhesive composition comprising the polyisocyanate composition according to any one of claims 1 to 7 and a crosslinkable functional group-containing polymer having a glass transition temperature of 0 ° C. or lower.
The pressure-sensitive adhesive composition according to claim 10, wherein the crosslinkable functional group-containing polymer is an acrylic polymer.
With the base material
A pressure-sensitive adhesive layer is provided on the substrate.
A pressure-sensitive adhesive sheet in which the pressure-sensitive adhesive layer is made of a cured product of the pressure-sensitive adhesive composition according to claim 10.
The pressure-sensitive adhesive sheet according to claim 12, wherein the thickness of the pressure-sensitive adhesive layer is 1 μm or more and 1000 μm or less.
A pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer having a thickness of 50 μm, which is obtained by applying the pressure-sensitive adhesive composition on a peel-treated polyethylene terephthalate film having a thickness of 38 μm, drying at 130 ° C. for 3 minutes, and curing the pressure-sensitive adhesive composition, is formed at 23 ° C. and 50 ° C. After storage in a% RH environment for 7 days, the gel is wrapped in a mesh sheet, immersed in ethyl acetate at 23 ° C for 1 week, taken out, and then dried at 120 ° C for 2 hours to obtain a gel fraction of 20 mass. The pressure-sensitive adhesive sheet according to claim 12 or 13, which is% or more and 99% by mass or less.
A pressure-sensitive adhesive sheet having a width of 20 mm and a length of 100 mm provided with a pressure-sensitive adhesive layer having a thickness of 50 μm obtained by applying the pressure-sensitive adhesive composition onto a polyethylene terephthalate film having a thickness of 25 μm, drying at 130 ° C. for 3 minutes, and curing the pressure-sensitive adhesive composition. After storage for 7 days in a 23 ° C, 50% RH environment, a SUS304BA steel plate was used as an adherend, crimped once back and forth with a 2 kg roller, cured at 23 ° C for 30 minutes, and then measured at a speed of 23 ° C, 300 mm / min. The pressure-sensitive adhesive sheet according to any one of claims 12 to 14, wherein the 180-degree peel adhesive strength is 0.05 N / 20 mm or more and 55 N / 20 mm or less.
The pressure-sensitive adhesive layer having a thickness of 50 μm, which is obtained by applying the pressure-sensitive adhesive composition on a stripped polyethylene terephthalate film having a thickness of 38 μm and drying at 130 ° C. for 3 minutes to cure the pressure-sensitive adhesive layer, is formed on the stripped polyethylene terephthalate film. According to any one of claims 12 to 15, the haze value measured by a haze meter of the adhesive sheet bonded on the glass having a haze value of 0.1% after peeling from The described adhesive sheet.
The polyisocyanate composition according to any one of claims 1 to 7, the glass transition temperature is 0 ° C. or higher and 100 ° C. or lower, the hydroxyl value is 10 mgKOH / g or higher and 400 mgKOH / g or lower, and the weight average molecular weight is 5. A resin composition containing an acrylic polyol having a size of .00 × 10 3 or more and 1.0 × 105 or less is cured at 90 ° C. for 30 minutes and stored at 23 ° C. in a 65% humidity environment for 168 hours to have a film thickness of 40 μm. It is a resin film of
A test piece having a width of 10 mm and a length of 100 mm of the resin film is set in a tensile tester so that the grip distance is 20 mm, and the breaking point stress in the tensile test measured at a speed of 20 mm / min is 2.0 MPa or more. There are coatings, films and adhesive compositions.
The polyisocyanate composition according to any one of claims 1 to 7, the glass transition temperature is 0 ° C. or higher and 100 ° C. or lower, the hydroxyl value is 10 mgKOH / g or higher and 400 mgKOH / g or lower, and the weight average molecular weight is 5. A resin composition containing an acrylic polyol having a thickness of .00 × 10 3 or more and 1.0 × 105 or less is cured at 90 ° C. for 30 minutes and stored at 23 ° C. in a 65% humidity environment for 168 hours to have a film thickness of 40 μm. It is a resin film of
A test piece having a width of 10 mm and a length of 100 mm of the resin film was set in a tensile tester so as to have a gripping tool distance of 20 mm, and fracture to 140% elongation stress in a tensile test measured at a speed of 20 mm / min. A coating film, a film and an adhesive composition having a point stress of 1.1 or more.
Derived from at least one diisocyanate selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, and polycaprolactone polyols (A2) and polyether polyols (B2).
A polyisocyanate composition containing 20 parts by mass or more of polypropylene glycol with respect to 100 parts by mass of the polyether polyol (B2).
The number average molecular weight of the polycaprolactone polyol (A2) is 500 or more and 1500 or less, and
The polyisocyanate composition according to claim 19, wherein the polyether polyol (B2) has a number average molecular weight of 1000 or more and 7000 or less.
The polyisocyanate composition according to claim 20, wherein in the polyether polyol (B2), the mass ratio of the polytetramethylene ether glycol to the polypropylene glycol is 0/100 or more and 60/40 or less.
The polyisocyanate composition according to any one of claims 19 to 21, wherein the molar ratio of the isocyanate group of the diisocyanate to the hydroxyl groups of the polycaprolactone polyol (A2) and the polyether polyol (B2) is 2 or more and 10 or less. thing.
The polyisocyanate composition according to any one of claims 19 to 22, wherein the mass ratio of the polycaprolactone polyol (A2) to the polyether polyol (B2) is 10/90 or more and 90/10 or less.
A resin composition comprising the polyisocyanate composition according to any one of claims 19 to 23 and a polyol.
The resin composition according to claim 24, which is a pressure-sensitive adhesive composition.