JP2023160575A - Two-pack curable polyurethane resin composition - Google Patents

Abstract

To achieve both moist heat resistance and tensile elongation.SOLUTION: A two-pack curable polyurethane resin composition according to an embodiment contains: a first component containing polyols and a terpene resin; and a second component containing a polyisocyanate. The polyols include 40 mass% or more of a polybutadiene polyol and/or a hydrogenated polybutadiene polyol and further include 5-40 mass% of a (meth)acrylic polyol. The content of the terpene resin is 3-60 pts.mass based on 100 pts.mass of the polyols.SELECTED DRAWING: None

Description

The present invention relates to a two-part curable polyurethane resin composition, electrical and electronic components using the same, and a polyol composition for the two-part curable polyurethane resin composition.

Conventionally, for example, electronic circuit boards and electronic components have been sealed using polyurethane resin compositions to protect them from external factors, and it is known that polybutadiene polyols are used as the polyol in polyurethane resin compositions. It is being

For example, in Patent Document 1, in a two-part curable polyurethane resin composition including a first component containing a polyol and a second component containing a polyisocyanate, a polybutadiene polyol is used as the polyol, and a castor oil-based polyol is further added. Good things are also mentioned. Patent Document 1 also discloses that a terpene resin is used together with polybutadiene polyol in the first component, which improves the compatibility of the first component, and also provides a polyurethane resin with high adhesion to the substrate and low dielectric constant. It is stated that a resin can be obtained.

Patent No. 6916404

When the two-component curable polyurethane resin composition described in Patent Document 1 was further investigated, it was found that it was not sufficient in terms of heat and humidity resistance. In order to improve the heat-and-moisture resistance, we investigated changing the polyol used in combination with the polybutadiene polyol, and found that depending on the formulation, the tensile elongation of the cured product could be significantly reduced.

In view of the above points, the embodiments of the present invention aim to provide a two-component curable polyurethane resin composition that can achieve both heat and humidity resistance and tensile elongation.

The present invention includes the embodiments shown below.
[1] A first component containing a polyol and a terpene resin, and a second component containing a polyisocyanate, the polyol containing 40% by mass or more of a polybutadiene polyol and/or a hydrogenated polybutadiene polyol, and the polyol containing: A two-component curable polyurethane resin composition further comprising 5 to 40% by mass of (meth)acrylic polyol, and the content of the terpene resin is 3 to 60 parts by mass based on 100 parts by mass of the polyol.
[2] The two-part curable polyurethane resin composition according to [1], wherein the polyol further contains 4 to 15% by mass of an alkylene polyol having 7 or more and 9 or less carbon atoms.
[3] The two-component curable polyurethane resin composition according to [1] or [2], which is used for encapsulating electrical and electronic components.
[4] An electrical and electronic component resin-sealed using the two-part curable polyurethane resin composition according to [1] or [2].
[5] A polyol composition used as a polyol component of a two-component curable polyurethane resin composition, which contains a polyol and a terpene resin, and the polyol contains 40% by mass or more of a polybutadiene polyol and/or a hydrogenated polybutadiene polyol. A polyol composition, wherein the polyol further contains 5 to 40% by mass of (meth)acrylic polyol, and the content of the terpene resin is 3 to 60 parts by mass based on 100 parts by mass of the polyol.

According to the embodiments of the present invention, it is possible to provide a two-component curable polyurethane resin composition that can achieve both heat and humidity resistance and tensile elongation.

The two-part curable polyurethane resin composition according to the present embodiment includes a first component containing a polyol (A) and a terpene resin (B), and a second component containing a polyisocyanate (C). Polyol (A) contains polybutadiene polyol (A1-1) and/or hydrogenated polybutadiene polyol (A1-2), and (meth)acrylic polyol (A2).

<First component>
[Polybutadiene polyol (A1-1) and/or hydrogenated polybutadiene polyol (A1-2)]
The polyol (A) contained in the first component is polybutadiene polyol (A1-1) and/or hydrogenated polybutadiene polyol (A1-2) (hereinafter, both may be collectively referred to as "PB polyol (A1)". )including.

The polybutadiene polyol (A1-1) preferably has a 1,4-bond type, 1,2-bond type, or a mixture of these polybutadiene structures and at least two hydroxy groups in the molecule, and both terminals of the polybutadiene structure More preferably, each has a hydroxy group.

The hydroxyl value of the polybutadiene polyol (A1-1) may be, for example, 10 to 200 mgKOH/g, 15 to 150 mgKOH/g, or 20 to 120 mgKOH/g. From the viewpoint of adhesion and compatibility, the hydroxyl value of the polybutadiene polyol (A1-1) is preferably 25 to 100 mgKOH/g, more preferably 40 to 90 mgKOH/g. In this specification, the hydroxyl value is measured according to method A of JIS K1557-1:2007.

Hydrogenated polybutadiene polyol (A1-2) has a hydrogenated structure compared to polybutadiene polyol (A1-1), and some or all of the unsaturated double bonds contained in the polybutadiene polyol are hydrogenated. It is attached. The degree of hydrogenation of the hydrogenated polybutadiene polyol (A1-2) is not particularly limited, and for example, the iodine value may be 50 g/100 g or less, or 30 g/100 g or less. In this specification, the iodine value is measured according to JIS K0070:1992.

The hydroxyl value of the hydrogenated polybutadiene polyol (A1-2) may be, for example, 10 to 200 mgKOH/g, 15 to 150 mgKOH/g, 20 to 120 mgKOH/g, 25 to 100 mgKOH/g, or 40 to 90 mgKOH /g may be sufficient.

As the PB polyol (A1), it is more preferable to use polybutadiene polyol (A1-1) from the viewpoint of tensile strength.

[(meth)acrylic polyol (A2)]
The polyol (A) contained in the first component contains a (meth)acrylic polyol (A2) as well as a PB polyol (A1). By adding (meth)acrylic polyol (A2), moist heat resistance can be improved while maintaining good tensile elongation.

(Meth)acrylic polyol (A2) is an acrylic polymer having multiple hydroxy groups. The (meth)acrylic polyol (A2) is a homopolymer or copolymer of a (meth)acrylic monomer having a hydroxy group, or another monomer having a polymerizable unsaturated bond in a (meth)acrylic monomer having a hydroxy group. An example is a copolymerized product.

As used herein, "(meth)acrylic polyol" means acrylic polyol and/or methacrylic polyol. "(Meth)acrylic monomer" means an acrylic monomer and/or a methacrylic monomer. "(Meth)acrylic acid" means acrylic acid and/or methacrylic acid. "(Meth)acrylamide" means acrylamide and/or methacrylamide.

Examples of (meth)acrylic monomers having a hydroxy group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 3-hydroxy(meth)acrylate. -Hydroxyalkyl (meth)acrylic acid esters such as hydroxypropyl and 4-hydroxybutyl (meth)acrylate, (meth)acrylic acid monoester of glycerin, and triols such as (meth)acrylic acid monoester of trimethylolpropane ( Examples include meth)acrylic acid monoester. Any one type of these may be used, or two or more types may be used in combination.

Examples of other monomers having polymerizable unsaturated bonds include methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, and (meth)acrylate. Isobutyl, n-hexyl (meth)acrylate, alkyl (meth)acrylates such as 2-ethylhexyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, (meth)acrylate, etc. ) Alkoxyalkyl (meth)acrylates such as 3-methoxybutyl acrylate, unsaturated carboxylic acids such as (meth)acrylic acid, maleic acid, itaconic acid, unsaturated carboxylic acids such as (meth)acrylamide, N-methylol (meth)acrylamide, etc. Examples include saturated amide, styrene, vinyltoluene, vinyl acetate, acrylonitrile, and the like. These may be used alone or in combination of two or more. Among these, (meth)acrylic acid esters such as alkyl (meth)acrylate and/or alkoxyalkyl (meth)acrylate are preferably used.

The hydroxyl value of the (meth)acrylic polyol (A2) may be, for example, 10 to 200 mgKOH/g, 20 to 180 mgKOH/g, 50 to 150 mgKOH/g, or 80 to 130 mgKOH/g.

The weight average molecular weight (Mw) of the (meth)acrylic polyol (A2) may be, for example, 1,000 to 30,000, 1,200 to 10,000, 1,500 to 5,000, or 1,800 to 3,000. In this specification, the weight average molecular weight is determined by a GPC device using tetrahydrofuran (THF) as a solvent, and is calculated as a polystyrene equivalent value. The specific measurement conditions are as follows.
・Column: Polystyrene gel column manufactured by Showa Denko (SHODEX GPC KF-601 + SHODEX GPC KF-602 + SHODEX GPC KF-603 + SHODEX GPC KF-604 connected in series in this order)
・Column temperature: 40℃
・Detector: Differential refractive index detector (RI-504 manufactured by Showa Denko)
・Flow rate: 0.6 mL/min.
・Sample injection amount: 10μL
・Sample concentration: 0.2% by mass THF solution

The (meth)acrylic polyol (A2) may be synthesized by a known polymerization method, or a commercially available product may be used. Commercially available products include, for example, "ARUFON UH-2000, UH-2032, UH-2041, UH-2190" manufactured by Toagosei Co., Ltd.

[Alkylene polyol (A3)]
The polyol (A) contained in the first component may further contain an alkylene polyol (A3) having 7 to 9 carbon atoms, along with the PB polyol (A1) and the (meth)acrylic polyol (A2). By adding alkylene polyol (A3), tensile strength can be improved.

The alkylene polyol (A3) having 7 to 9 carbon atoms may be a diol having two hydroxy groups or three or more hydroxy groups in one molecule, but is preferably a diol. Specific examples of the alkylene polyol (A3) having 7 to 9 carbon atoms include 1,7-heptanediol, 1,2-heptanediol, 2,3-heptanediol, 5-methyl-2,4-hexanediol, 2 -Methyl-2,5-hexanediol, 2,4-dimethyl-2,4-pentanediol, 2,4-dimethyl-1,5-pentanediol, 2-ethyl-1,5-pentanediol, 2-ethyl Heptanediol such as -1,3-pentanediol; 1,8-octanediol, 1,2-octanediol, 1,3-octanediol, 1,4-octanediol, 2,4-octanediol, 2-methyl -1,2-heptanediol, 2-methyl-1,3-heptanediol, 2-methyl-2,3-heptanediol, 2-ethyl-1,2-hexanediol, 2-ethyl-1,3-hexane Diol, 2-ethyl-1,5-hexanediol, 2-ethyl-1,6-hexanediol, 2,5-dimethyl-2,5-hexanediol, 3,4-dimethyl-3,4-hexanediol, Octanediol such as 2,5-dimethyl-3,4-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-propyl-1,2-pentanediol; 1,9-nonanediol, 1,2-nonanediol, 2-methyl-1,8-octanediol, 2-ethyl-1,4-heptanediol, 2,6-dimethyl-3,5-heptanediol, 2,6-dimethyl-2, Examples include nonanediol such as 6-heptanediol, 2,4-diethyl-1,5-pentanediol, and 2-butyl-2-ethyl-1,3-propanediol. Any one type of these may be used, or two or more types may be used in combination.

As the alkylene polyol (A3), branched alkylene diol is preferred. A branched alkylene diol is an alkylene diol having a tertiary carbon atom and/or a quaternary carbon atom in the molecule. More preferably, a diol having a tertiary carbon atom in the molecule, a hydroxy group bonded to a primary carbon atom, and a hydroxy group bonded to a primary carbon atom or a secondary carbon atom is used. It is. Such diols include, for example, 2,4-dimethyl-1,5-pentanediol, 2-ethyl-1,5-pentanediol, 2-ethyl-1,3-pentanediol, 2-methyl-1,3 -heptanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-1,5-hexanediol, 2-ethyl-1,6-hexanediol, 2,2,4-trimethyl-1,3-pentane diol, 2-methyl-1,8-octanediol, 2-ethyl-1,4-heptanediol, 2,4-diethyl-1,5-pentanediol and the like. Any one type of these may be used, or two or more types may be used in combination.

[Polyol (A)]
Polyol (A) may be composed only of PB polyol (A1) and (meth)acrylic polyol (A2), or may be composed only of PB polyol (A1), (meth)acrylic polyol (A2) and alkylene polyol (A3). In addition to these, other polyols (A4) may also be contained. The polyol (A) may be composed of only bifunctional ones or may contain trifunctional or more functional ones, but when the polyisocyanate (C) is composed of only bifunctional ones, the polyurethane resin composition It is preferable to contain a trifunctional or higher functional polyol in order to make it thermosetting.

Other polyols (A4) are compounds having a plurality of hydroxy groups in the molecule, and include various polyols other than PB polyol (A1), (meth)acrylic polyol (A2), and alkylene polyol (A2). Specific examples include polyether polyol, polyester polyol, polycarbonate polyol, dimer acid polyol, polycaprolactone polyol, castor oil polyol, polyisoprene polyol, hydrogenated polyisoprene polyol, and the like. In addition, low molecular weight polyols commonly used as crosslinking agents, such as N,N-bis(2-hydroxypropyl)aniline, hydroquinone-bis(β-hydroxyethyl) ether, resorcinol-bis(β-hydroxyethyl) ether Aromatic alcohols such as

The content of PB polyol (A1) in 100% by mass of polyol (A) is 40% by mass or more, more preferably 50% by mass or more, still more preferably 60% by mass or more, even more preferably 70% by mass or more. % by mass or more. When the content of the PB polyol (A1) is 40% by mass or more, adhesion to electronic circuit boards and the like can be improved, and the dielectric constant can be lowered. The content of the PB polyol (A1) is 95% by mass or less, preferably 90% by mass or less, more preferably 85% by mass or less, and may be 80% by mass or less.

The content of (meth)acrylic polyol (A2) in 100% by mass of polyol (A) is 5 to 40% by mass. When the content of the (meth)acrylic polyol (A2) is 5% by mass or more, moist heat resistance and tensile elongation can be improved, and when the content is 40% by mass or less, the compatibility of the first component can be improved. The decline can be suppressed. The content of the (meth)acrylic polyol (A2) is preferably 10% by mass or more, more preferably 12% by mass or more. The content of the (meth)acrylic polyol (A2) is preferably 35% by mass or less, more preferably 30% by mass or less, and may be 25% by mass or less.

When the alkylene polyol (A3) is contained in the polyol (A), the content of the alkylene polyol (A3) in 100% by mass of the polyol (A) is preferably 4 to 15% by mass. When the content of the alkylene polyol (A3) is 4% by mass or more, the tensile strength can be improved, and when the content is 15% by mass or less, a decrease in the compatibility of the first component can be suppressed. The content of alkylene polyol (A3) may be 5% by mass or more, preferably 12% by mass or less, and more preferably 10% by mass or less.

[Terpene resin (B)]
The first component contains a terpene resin (B) together with a PB polyol (A1) and a (meth)acrylic polyol (A2). Since the terpene resin (B) has excellent compatibility with the PB polyol (A1), separation of the first component and turbidity can be suppressed. Furthermore, by blending the terpene resin (B) with the PB polyol (A1) and (meth)acrylic polyol (A2), it is possible to achieve both moist heat resistance and tensile elongation. In addition, it is possible to improve the adhesion with electronic circuit boards and the like, leading to maintenance or improvement of low dielectric properties.

Terpene resin (B) is a polymer containing terpene as a constituent monomer. Terpenes (also referred to as terpene monomers) include, for example, α-pinene, β-pinene, limonene (including racemic dipentene), myrcene, alloocimene, ocimene, α-phellandrene, β-phellandrene, α- Examples include monoterpenes such as terpinene, γ-terpinene, and sabinene, and any one type or two or more types of these can be used in combination. Among these, monocyclic monoterpenes such as α-pinene, β-pinene, limonene, α-phellandrene, β-phellandrene, α-terpinene, and γ-terpinene are preferred, and more preferably α-pinene, At least one member selected from the group consisting of β-pinene and limonene.

Examples of the terpene resin (B) include the following (B1) to (B3).
・Polyterpene resin (B1) whose constituent monomer is a homopolymer or copolymer consisting only of terpene monomers
・Aromatic modified terpene resin (B2) which is a copolymer of terpene monomer and aromatic monomer
・Terpene phenol resin (B3), which is a copolymer of terpene monomer and phenolic monomer
Any one of these (B1) to (B3) may be used alone, or two or more may be used in combination.

Examples of the aromatic monomer constituting the aromatic modified terpene resin (B2) include styrene, α-methylstyrene, 4-methylstyrene, 2,4-dimethylstyrene, and the like.

Examples of the phenolic monomer constituting the terpene phenol resin (B3) include phenol, cresol, xylenol, and the like.

Suitable examples of the terpene resin (B) include polyterpene resin (B1) which is at least one homopolymer or copolymer selected from the group consisting of α-pinene, β-pinene, and limonene; , an aromatic modified terpene resin (B2) which is a copolymer of styrene and at least one terpene monomer selected from the group consisting of β-pinene and limonene, from the group consisting of α-pinene, β-pinene and limonene. Examples include terpene phenol resin (B3) which is a copolymer of at least one selected terpene monomer and phenol.

The content of the terpene resin (B) is 3 to 60 parts by mass based on 100 parts by mass of the polyol (A). When the content of the terpene resin (B) is 60 parts by mass or less, bleeding of the terpene resin (B) after curing of the polyurethane resin can be suppressed. The content of the terpene resin (B) is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, still more preferably 12 parts by mass or more, and may be 15 parts by mass or more. The content of the terpene resin (B) is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and still more preferably 30 parts by mass or less.

[Other ingredients]
In addition to the above-mentioned components, the first component may include a catalyst, an antioxidant, a foam stabilizer, a diluent, a flame retardant, an ultraviolet absorber, a coloring agent, a filler, a plasticizer, etc., as necessary. Various additives can be added within the range that does not impair the purpose of this embodiment.

As the catalyst, for example, metal catalysts such as organotin catalysts, organolead catalysts, and organobismuth catalysts, and various urethane polymerization catalysts such as amine catalysts can be used.

The plasticizer is not particularly limited, and examples thereof include phthalate ester, adipate ester, phosphate ester, trimellitate ester, polyester plasticizer, acrylic plasticizer, and the like. As the plasticizer, it is preferable to use an acrylic plasticizer, which can reduce the viscosity of the first component. The content of the plasticizer is not particularly limited, and may be, for example, 30 parts by mass or less, or 5 to 20 parts by mass, based on 100 parts by mass of the polyol (A).

<Second component>
[Polyisocyanate (C)]
The polyisocyanate (C) contained in the second component is not particularly limited, and various polyisocyanate compounds having two or more isocyanate groups in one molecule can be used. Examples of the polyisocyanate (C) include aromatic polyisocyanate (C1), aliphatic polyisocyanate (C2), and alicyclic polyisocyanate (C3). More than one species may be used in combination.

Examples of the aromatic polyisocyanate (C1) include tolylene diisocyanate (TDI, such as 2,4-TDI, 2,6-TDI), diphenylmethane diisocyanate (MDI, such as 2,2'-MDI, 2,4'- MDI, 4,4'-MDI), 4,4'-dibenzyl diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate (XDI), 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, and these modified forms and polynuclear forms.

Examples of the aliphatic polyisocyanate (C2) include tetramethylene diisocyanate, dodecamethylene diisocyanate, hexamethylene diisocyanate (HDI), 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and lysine. Examples include diisocyanate, 2-methylpentane-1,5-diisocyanate, 3-methylpentane-1,5-diisocyanate, and modified products and polynuclear products thereof.

Examples of the alicyclic polyisocyanate (C3) include isophorone diisocyanate (IPDI), hydrogenated xylylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4-cyclohexane diisocyanate, methylcyclohexylene diisocyanate, 1,3- Bis(isocyanatomethyl)cyclohexane, and modified and polynuclear forms thereof.

Examples of the above-mentioned modified products include isocyanurate modified products, allophanate modified products, biuret modified products, adduct modified products, carbodiimide modified products, and the like.

In one embodiment, the polyisocyanate (C) preferably includes an aromatic polyisocyanate (C1). By using aromatic polyisocyanate (C1), the effect of improving tensile properties can be enhanced. More preferably, at least one member selected from the group consisting of diphenylmethane diisocyanate, modified products and polynuclear products thereof is used as the polyisocyanate (C).

The content of polyisocyanate (C) in the two-part curable polyurethane resin composition is not particularly limited, and may be, for example, 1 to 70 parts by mass, or 3 to 50 parts by mass, based on 100 parts by mass of polyol (A). It may be 5 to 40 parts by mass.

The polyisocyanate (C) may be composed of only bifunctional ones or may contain trifunctional or more functional ones, but when the polyisocyanate (A) is composed of only bifunctional ones, the polyurethane resin composition It is preferable to contain a trifunctional or higher functional polyisocyanate in order to make it thermosetting.

The ratio of polyisocyanate (C) to polyol (A) is not particularly limited, and for example, NCO/OH (index) may be 0.6 to 1.5, or 0.7 to 1.4, It may be 0.8 to 1.3 or 0.9 to 1.2. Here, NCO/OH is the molar ratio of the isocyanate groups contained in the polyisocyanate (C) to the hydroxy groups contained in the polyol (A). NCO/OH is calculated using the hydroxyl value of polyol (A) and the isocyanate value of polyisocyanate (C). The isocyanate value is calculated by isocyanate value = {(isocyanate content) x 56110}/(42.02 x 100) using the isocyanate content measured according to method A of JIS K1603-1:2007. Ru.

[Other ingredients]
The second component may be composed only of polyisocyanate (C), or in addition to polyisocyanate (C), if necessary, it may contain a catalyst, an antioxidant, a foam stabilizer, a diluent, a flame retardant, etc. , ultraviolet absorbers, colorants, fillers, plasticizers, and other various additives may be added to the extent that the purpose of the present embodiment is not impaired.

<Two-component curable polyurethane resin composition>
The two-part curable polyurethane resin composition according to the present embodiment is usually composed of a first part as a first component and a second part as a second component. In addition, a third component containing the above-mentioned other components as an optional component may be provided as a third liquid.

The two-component curable polyurethane resin composition can be manufactured by preparing the first component and the second component, respectively. That is, the first component and the second component may be filled in separate containers. good. The first component and the second component filled in separate containers may be mixed at the time of use, so that the polyol (A) and the polyisocyanate (C) react to form a polyurethane resin, which may be cured. At that time, it may be cured by heating. The two-component curable polyurethane resin composition according to the embodiment may be obtained by mixing the first component and the second component, may be in a liquid state before curing, or may be cured.

<Polyol composition>
The polyol composition according to one embodiment is used as a polyol component of a two-part curable polyurethane resin composition, and the first component corresponds to this. Therefore, the polyol composition contains a polyol (A) and a terpene resin (B), the polyol (A) contains 40% by mass or more of a polybutadiene polyol and/or a hydrogenated polybutadiene polyol (A1), and the polyol (A ) further contains 5 to 40% by mass of (meth)acrylic polyol (A2), and the content of terpene resin (B) is 3 to 60 parts by mass based on 100 parts by mass of polyol (A). The polyol (A) may further contain 4 to 15% by mass of an alkylene polyol (A2) having 7 to 9 carbon atoms. The details of the polyol (A), terpene resin (B), and other components are as described above, and their explanation will be omitted.

<Applications of two-part curable polyurethane resin composition>
The use of the two-part curable polyurethane resin composition according to the present embodiment is not particularly limited, but it is preferably used for sealing electrical and electronic components. Examples of electrical and electronic components include transformers such as transformer coils, choke coils, and reactor coils, device control boards, sensors, and wireless communication components. The two-component curable polyurethane resin composition has excellent low dielectric properties (that is, has a low dielectric constant) and is not easily affected by radio waves. Therefore, the two-component curable polyurethane resin composition is preferably used as a sealing material for sealing, that is, covering, a wireless communication component that performs wireless communication with a resin in order to protect the wireless communication component from the external environment. For example, it may be used as a sealing material for a sensor that transmits detected information via wireless communication.

Electrical and electronic components resin-encapsulated using the two-component curable polyurethane resin composition according to the present embodiment include, for example, electric washing machines, toilet seats, water heaters, water purifiers, baths, dishwashers, solar panels, Can be used for power tools, cars, motorcycles, etc.

Hereinafter, the two-component curable polyurethane resin composition will be described in detail based on Examples and Comparative Examples, but the present invention is not limited thereto.

The raw materials used in the Examples and Comparative Examples are shown below.

[PB polyol (A1)]
・Polybutadiene polyol 1: Hydroxyl value 47 mgKOH/g, product name: Poly bd R-45HT, manufactured by Idemitsu Kosan Co., Ltd. ・Polybutadiene polyol 2: Hydroxyl value 107 mgKOH/g, product name: Poly bd R-15HT, Idemitsu Kosan Co., Ltd. ), hydrogenated polybutadiene polyol: hydroxyl value 49 mgKOH/g, product name: KRASOL H-LBH-2000, manufactured by Clay Valley.

[(meth)acrylic polyol (A2)]
・(Meth)acrylic polyol 1: Hydroxyl value 120mgKOH/g, weight average molecular weight 2500, product name: ARUFON UH-2041, manufactured by Toagosei Co., Ltd.・(meth)acrylic polyol 2: Hydroxyl value 110mgKOH/g, weight average molecular weight 2000, Product name: ARUFON UH-2032, manufactured by Toagosei Co., Ltd.

[Alkylene polyol (A3)]
・Alkylene polyol 1: 2-ethyl-1,3-hexanediol, product name: octanediol, manufactured by KH Neochem Co., Ltd. ・Alkylene polyol 2: 2,4-diethyl-1,5-pentanediol, product name: KYOWA Diol PD-9, manufactured by KH Neochem Co., Ltd.

[Other polyols]
- Castor oil polyol: hydroxyl value 160mgKOH/g, product name: castor oil, manufactured by Ito Oil Co., Ltd. - Polyester polyol: hydroxyl value 56mgKOH/g, product name: Kuraray Polyol P-2010, manufactured by Kuraray Co., Ltd.

[Terpene resin (B)]
・Terpene resin 1: Limonene-styrene copolymer, active ingredient 50% by mass, product name: YS Resin LP, manufactured by Yasuhara Chemical Co., Ltd. ・Terpene resin 2: Pinene-dipentene copolymer, active ingredient 80% by mass, product name : Dymaron, manufactured by Yasuhara Chemical Co., Ltd. Terpene resin 3: Phenol/α-pinene copolymer, active ingredient 100% by mass, product name: YS POLYSTER T80, manufactured by Yasuhara Chemical Co., Ltd.

[Polyisocyanate (C)]
・Aromatic polyisocyanate: Polymeric MDI, product name: Millionate MR-200, manufactured by Tosoh Corporation

[Other ingredients]
・Acrylic plasticizer: Acrylic polymer, weight average molecular weight 1600, product name: ARUFON UP-1021, manufactured by Toagosei Co., Ltd.

[Examples 1 to 16 and Comparative Examples 1 to 6]
Two-part curable polyurethane resin compositions of each Example and each Comparative Example were prepared according to the formulations (parts by mass) shown in Tables 1 to 3 below. During preparation, a predetermined amount of the first component shown in Tables 1 to 3 was weighed, and the mixture was stirred and mixed while melting with appropriate heat, and after mixing, the temperature was adjusted to 25°C. Subsequently, the second component (polyisocyanate (C)) adjusted to 25° C. was added to this mixture as shown in Tables 1 to 3, mixed with stirring, and defoamed.

In Tables 1 to 3, the values in parentheses for the formulations of terpene resin 1 and terpene resin 2 indicate the amounts of the active ingredients.

For each two-component curable polyurethane resin composition, tensile strength, tensile elongation, dielectric constant, adhesion, compatibility, and moist heat resistance were measured and evaluated. The measurement and evaluation methods are as follows.

[Tensile strength, tensile elongation]
The defoamed two-part curable polyurethane resin composition was poured into a 3 mm thick mold and cured at 80° C. for 16 hours (overnight) to produce a 3 mm thick resin sheet. The resin sheet was punched into a No. 3 dumbbell shape to provide a sample for measurement. The measurement was carried out using a device manufactured by Shimadzu Corporation (body model: AG-X Plus, name: Shimadzu Precision Universal Testing Machine Autograph), with the tensile speed set at 500 mm/min and the distance between the chucks set at 40 mm. The test was carried out three times, and the average values of tensile strength (stress at break) and tensile elongation (elongation rate at break) were calculated and evaluated according to the following criteria.

(Tensile strength evaluation criteria)
A: Tensile strength is 3.0 MPa or more B: Tensile strength is 2.5 MPa or more and less than 3.0 MPa C: Tensile strength is 2.0 MPa or more and less than 2.5 MPa D: Tensile strength is 1.5 MPa or more and less than 2.0 MPa Less than E: Tensile strength is less than 1.5 MPa

(Tensile elongation evaluation criteria)
A: Elongation rate is 130% or more B: Elongation rate is 110% or more and less than 130% C: Elongation rate is 90% or more and less than 110% D: Elongation rate is 70% or more and less than 90% E: Elongation rate is 70% %less than

[Permittivity]
The defoamed two-part curable polyurethane resin composition was poured into a 3 mm thick mold and cured at 80° C. for 16 hours (overnight) to produce a 3 mm thick resin sheet. The resin sheet was cut into sheets of 50 mm x 50 mm x 3 mm and used as samples for measurement. The measurement was carried out using a device manufactured by Agilent Technologies (body model: E4980A, name: Precision LCR Meter; electrode part model: 16451B, name: DIELECTRIC TEST FIXTURE), and the dielectric constant at a frequency of 1 MHz was measured. The value of dielectric constant (relative permittivity) was measured and evaluated according to the following criteria.
A: Dielectric constant is 2.8 or less B: Dielectric constant is greater than 2.8 and less than 3.0 C: Dielectric constant is greater than 3.0 and less than 3.2 D: Dielectric constant is greater than 3.2 and 3.4 Below E: Dielectric constant is greater than 3.4

[Adhesion]
The defoamed two-part curable polyurethane resin composition was dropped to a diameter of about 1 cm onto a commercially available FR-4 epoxy substrate, and cured at 80° C. for 16 hours (overnight) to cure. Aiming at the boundary between the cured polyurethane resin and the epoxy substrate, the resin was scraped off with a cutter knife, and the polyurethane resin remaining on the substrate was visually confirmed. For evaluation, cohesive failure is defined as a state in which the polyurethane resin remains on the substrate, and interfacial delamination is defined as a state in which the polyurethane resin is peeled off from the board. When both conditions are present, the following conditions are considered depending on the area ratio: Evaluation was performed based on the criteria.
A: 100% cohesive failure
B: Cohesive failure is 75% or more and less than 100%, interfacial peeling is more than 0% and less than 25% C: Cohesive failure is more than 50% and less than 75%, interfacial peeling is more than 25% and less than 50% D: Cohesive failure is more than 25% Less than 50%, interfacial peeling is more than 50% and 75% or less E: Cohesive failure is less than 25%, interfacial peeling is 75% or more

[Compatibility]
The state of the liquid after mixing the first component was checked, and the compatibility of the first component was evaluated based on the following criteria. In the case of D and E, other evaluations were not conducted because they were separated.
A: Clear B: Slightly cloudy C: Cloudy D: Separation occurs after 30 minutes or more E: Separation occurs in less than 30 minutes

[Moist heat resistance]
The defoamed two-part curable polyurethane resin composition was poured into a 3 mm thick mold and cured at 80° C. for 16 hours (overnight) to produce a 3 mm thick resin sheet. The resin sheet was cut into sheets of 30 mm x 30 mm x 3 mm and used as samples for measurement. The measurement was carried out using a device manufactured by Espec Co., Ltd. (body model: EHS-212M, name: Highly Accelerated Life Testing Device), and the weight of the sample was measured before and after the durability test at a temperature of 121°C and a humidity of 85%. was measured, and the weight loss rate was calculated using the following formula, and evaluated using the following criteria.
Weight reduction rate [%] = - (M2 - M1) ÷ M1 x 100
M1: Sample weight before the start of the durability test M2: Sample weight after 200 hours of the durability test A: Weight reduction rate is 4% or less B: Weight reduction rate is greater than 4% and 5% or less C: Weight reduction rate is more than 5% D: Weight reduction rate is greater than 6% and 7% or less E: Weight reduction rate is greater than 7% or resin melting

The results are shown in Tables 1 to 3. In Comparative Example 1, the combined use of PB polyol (A1) and terpene resin (B) resulted in excellent compatibility, low dielectric properties, and excellent adhesion to the substrate, but (meth)acrylic polyol (A2) ), the tensile strength and moist heat resistance were poor. In Comparative Example 2, since the terpene resin (B) was not blended, the tensile elongation and adhesion were poor. In Comparative Example 3, the amount of PB polyol (A1) blended was small, so the tensile elongation was poor. In Comparative Example 4, the first component had poor compatibility and was separated, so other evaluations could not be performed. In Comparative Example 5 and Comparative Example 6, castor oil polyol or polyester polyol was used instead of (meth)acrylic polyol (A2), so the heat and humidity resistance was poor.

On the other hand, in Examples 1 to 16 in which PB polyol (A1), (meth)acrylic polyol (A2), and terpene resin (B) were used in combination, the tensile elongation significantly decreased compared to Comparative Example 1. The heat-and-moisture resistance was improved while suppressing the tensile elongation. In addition, results of adhesion, low dielectric properties, tensile strength, and compatibility of the first component were also obtained that were at or above a practical level. In Examples 1 to 12 and 16 in which alkylene polyol (A3) was further added, the effect of improving tensile strength was observed compared to Examples 13 to 15 in which alkylene polyol (A3) was not blended.

Note that the upper and lower limits of the various numerical ranges described in the specification can be arbitrarily combined, and all combinations are described herein as preferred numerical ranges. Furthermore, the description of the numerical range "X to Y" means from X to Y, not more than Y.

Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments, their omissions, substitutions, changes, etc. are included within the scope and gist of the invention as well as within the scope of the invention described in the claims and its equivalents.

Claims (5)

a first component containing a polyol and a terpene resin;
a second component containing a polyisocyanate;
The polyol contains 40% by mass or more of a polybutadiene polyol and/or a hydrogenated polybutadiene polyol,
The polyol further contains 5 to 40% by mass of (meth)acrylic polyol,
A two-part curable polyurethane resin composition, wherein the content of the terpene resin is 3 to 60 parts by mass based on 100 parts by mass of the polyol. The two-component curable polyurethane resin composition according to claim 1, wherein the polyol further contains 4 to 15% by mass of an alkylene polyol having 7 or more and 9 or less carbon atoms. The two-component curable polyurethane resin composition according to claim 1 or 2, which is used for encapsulating electrical and electronic components. An electrical and electronic component resin-sealed using the two-part curable polyurethane resin composition according to claim 1 or 2. A polyol composition used as a polyol component of a two-part curable polyurethane resin composition,
Contains polyols and terpene resins,
The polyol contains 40% by mass or more of a polybutadiene polyol and/or a hydrogenated polybutadiene polyol,
The polyol further contains 5 to 40% by mass of (meth)acrylic polyol,
A polyol composition, wherein the content of the terpene resin is 3 to 60 parts by mass based on 100 parts by mass of the polyol.