JP2023102105A - Two-liquid curing type polyurethane resin composition - Google Patents

Abstract

To improve tensile characteristics.SOLUTION: A two-liquid curing type polyurethane resin composition according to an embodiment of the present invention comprises: a first component including a polyol and a terpene resin; and a second component including a polyisocyanate. The polyol contains 40 mass% or more of a polybutadiene polyol and/or a hydrogenated polybutadiene polyol and, further, 4-15 mass% of a C7-9 alkylene polyol. A content of the terpene resin is 5-60 pts.mass relative to 100 pts.mass of the polyol.SELECTED DRAWING: None

Description

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

Conventionally, electronic circuit boards and electronic components have been sealed using polyurethane resin compositions in order to protect them from external factors, and it is known to use polybutadiene polyol as the polyol of the polyurethane resin composition.

For example, Patent Document 1 discloses an electrical insulating material comprising a hydroxyl group-containing liquid diene polymer, a polyisocyanate compound, a polycyclic aromatic hydrocarbon and a petroleum resin. Patent Document 2 discloses a heat-resistant moisture-proof insulating paint containing a polymer obtained by reacting hydroxyl-containing polybutadiene, hydroxyl-containing hydrogenated polybutadiene and polyisocyanate, a tackifier, and a solvent.

Patent Document 3 describes a two-component curable polyurethane resin composition containing a first component containing a polyol containing polybutadiene polyol and a terpene resin, and a second component containing a polyisocyanate. It also describes that by using a terpene resin together with polybutadiene polyol, the compatibility is improved, the adhesion to substrates and the like is improved, and a polyurethane resin having a low dielectric constant can be obtained.

JP-A-61-197620 JP-A-8-165454 Japanese Patent No. 6916404

As described above, according to the invention described in Patent Document 3, a two-part curable polyurethane resin composition having excellent compatibility, adhesion, and low dielectric properties is provided, but it was found that the tensile properties were not sufficient.

In view of the above points, an object of the embodiments of the present invention is to provide a two-part curable polyurethane resin composition capable of improving tensile properties.

The present invention includes embodiments shown below.
[1] Including the first component containing polyol and terpen resin and the second component containing polyisocyanate, the polyol contains 40 % by mass or or more polyrovadiol and / or water -contained polybodadiemporiors, and the polyol has a number of carbon and less than 9 or less. A two -liquid -cured polyurethane resin composition, which contains 4 to 15 % by mass of the alkillen polyol and has 5 to 60 parts of the polyol 100 parts by mass of the terpen resin.
[2] The two-component curable polyurethane resin composition according to [1], wherein the alkylene polyol is a diol having a hydroxy group bonded to a primary carbon atom and a hydroxy group bonded to a secondary carbon atom.
[3] The two-part curable polyurethane resin composition according to [1] or [2], wherein the polyisocyanate contains an aromatic polyisocyanate.
[4] The two-component curable polyurethane resin composition according to any one of [1] to [3], wherein the polyol further contains a castor oil-based polyol.
[5] The two-component curable polyurethane resin composition according to any one of [1] to [4], which is used for encapsulating electrical and electronic parts.
[6] An electric/electronic component resin-sealed using the two-component curing type polyurethane resin composition according to any one of [1] to [5].
[7] A polyol composition used as a polyol component of a two-part curable polyurethane resin composition, comprising a polyol and a terpene resin, wherein the polyol contains polybutadiene polyol and/or hydrogenated polybutadiene polyol in an amount of 40% by mass or more, the polyol further contains 4 to 15% by mass of an alkylene polyol having 7 to 9 carbon atoms, and the content of the terpene resin is 5 to 60 parts by mass relative to 100 parts by mass of the polyol.

According to an embodiment of the present invention, it is possible to provide a two-pack curable polyurethane resin composition capable of improving tensile properties.

The two-component curable polyurethane resin composition according to the present embodiment is a polyurethane resin composition containing a first component containing a polyol (A) and a terpene resin (B) and a second component containing a polyisocyanate (C), wherein the polyol (A) contains a polybutadiene polyol (A1-1) and/or a hydrogenated polybutadiene polyol (A1-2), and an alkylene polyol (A2) having 7 to 9 carbon atoms.

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

The polybutadiene polyol (A1-1) preferably has a 1,4-bonded, 1,2-bonded, or mixed polybutadiene structure in the molecule and at least two hydroxy groups, and more preferably has hydroxy groups at both ends of the polybutadiene structure.

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

The hydrogenated polybutadiene polyol (A1-2) has a hydrogenated structure with respect to the polybutadiene polyol (A1-1), and some or all of the unsaturated double bonds contained in the polybutadiene polyol are hydrogenated. The degree of hydrogenation of the hydrogenated polybutadiene polyol (A1-2) is not particularly limited. For example, the iodine value may be 50 g/100 g or less, or 30 g/100 g or less. As used herein, 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.

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

[Alkylene polyol (A2)]
For the polyol (A) contained in the first component, an alkylene polyol (A2) having 7 to 9 carbon atoms is used together with the PB polyol (A1). Addition of the alkylene polyol (A2) can improve tensile properties, particularly elongation.

The alkylene polyol (A2) having 7 to 9 carbon atoms may be a diol having two hydroxy groups in one molecule, or may have three or more hydroxy groups, but is preferably a diol. Specific examples of the alkylene polyol having 7 to 9 carbon atoms (A2) 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, and 2-ethyl-1. 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 - octanediol such as 1,3-hexanediol, 2-ethyl-1,5-hexanediol, 2-ethyl-1,6-hexanediol, 2,5-dimethyl-2,5-hexanediol, 3,4-dimethyl-3,4-hexanediol, 2,5-dimethyl-3,4-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-propyl-1,2-pentanediol; nonanediol such as 1,2-nonanediol, 2-methyl-1,8-octanediol, 2-ethyl-1,4-heptanediol, 2,6-dimethyl-3,5-heptanediol, 2,6-dimethyl-2,6-heptanediol, and 2-butyl-2-ethyl-1,3-propanediol. Any one of these may be used, or two or more thereof may be used in combination.

As the alkylene polyol (A2), it is preferable to use a diol having a hydroxy group bonded to a primary carbon atom and a hydroxy group bonded to a secondary carbon atom. Such diols include, for example, 1,2-heptanediol, 2-ethyl-1,3-pentanediol, 1,2-octanediol, 1,3-octanediol, 1,4-octanediol, 2-methyl-1,3-heptanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-1,5-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,2- nonanediol, 2-ethyl-1,4-heptanediol. Any one of these may be used, or two or more thereof may be used in combination.

Among these, branched alkylene diols are preferred. Branched alkylenediols are alkylenediols having tertiary and/or quaternary carbon atoms in the molecule. Specific examples include 2-ethyl-1,3-pentanediol, 2-methyl-1,3-heptanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-1,5-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, and 2-ethyl-1,4-heptanediol. More preferably, diols having tertiary carbon atoms in the molecule and having hydroxy groups bonded to primary carbon atoms and hydroxy groups bonded to secondary carbon atoms are used.

[Castor oil-based polyol (A3)]
The polyol (A) may further contain a castor oil-based polyol (A3). By adding the castor oil polyol (A3), the effect of improving the tensile properties can be enhanced. As the castor oil-based polyol (A3), castor oil, castor oil fatty acid, hydrogenated castor oil obtained by hydrogenating these, and polyol produced using hydrogenated castor oil fatty acid can be used. More specifically, the castor oil-based polyol (A3) includes, for example, castor oil, transesterified products of castor oil and other natural oils and fats, reaction products of castor oil and polyhydric alcohols, esterification reaction products of castor oil fatty acids and polyhydric alcohols, and polyols obtained by addition polymerization of alkylene oxides to these.

The hydroxyl value of the castor oil-based polyol (A2) is not particularly limited, and may be, for example, 50 to 250 mgKOH/g or 100 to 180 mgKOH/g.

[Polyol (A)]
The polyol (A) may be composed of the PB polyol (A1) and the alkylene polyol (A2) alone, or may be composed of the PB polyol (A1), the alkylene polyol (A2) and the castor oil-based polyol (A3) alone, or may further contain other polyols (A4) in addition to these. The polyol (A) may be composed only of bifunctional ones or may contain trifunctional or higher functional ones, but when the polyisocyanate (C) is composed only of difunctional ones, it preferably contains a trifunctional or higher polyol in order to make the polyurethane resin composition thermosetting.

Other polyols (A4) are compounds having multiple hydroxy groups in the molecule, and include various polyols other than PB polyols (A1), alkylene polyols (A2) and castor oil-based polyols (A3). Specific examples include polyether polyol, polyester polyol, polycarbonate polyol, dimer acid polyol, polycaprolactone polyol, acrylic polyol, polyisoprene polyol, and hydrogenated polyisoprene polyol. In addition, aromatic alcohols such as low-molecular-weight polyols that are generally used as cross-linking agents, such as N,N-bis(2-hydroxypropyl)aniline, hydroquinone-bis(β-hydroxyethyl)ether, and resorcinol-bis(β-hydroxyethyl)ether, can also be mentioned.

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, and still more preferably 60% by mass or more. When the content of the PB polyol (A1) is 40% by mass or more, it is possible to improve the adhesion to an electronic circuit board and the like, and to lower the dielectric constant. The content of the PB polyol (A1) is 96% by mass or less, preferably 92% by mass or less, may be 90% by mass or less, may be 85% by mass or less, or may be 80% by mass or less.

The content of the alkylene polyol (A2) in 100% by mass of the polyol (A) is 4 to 15% by mass. When the content of the alkylene polyol (A2) is 4% by mass or more, tensile properties can be improved, and when it is 15% by mass or less, deterioration of compatibility can be suppressed. The content of the alkylene polyol (A2) is preferably 5% by mass or more, preferably 12% by mass or less, and more preferably 10% by mass or less.

When the polyol (A) contains the castor oil-based polyol (A3), the content of the castor oil-based polyol (A3) in 100% by mass of the polyol (A) is, for example, 4 to 56% by mass, 10 to 40% by mass, or 15 to 30% by mass.

[Terpene resin (B)]
The first component contains a terpene resin (B) together with a PB polyol (A1) and an alkylene polyol (A2). Since the terpene resin (B) has excellent compatibility with the PB polyol (A1), separation and turbidity of the first component can be suppressed. In addition, by blending the terpene resin (B) together with the PB polyol (A1) and the alkylene polyol (A2), it is possible to improve the adhesion to electronic circuit boards and the like, and also to improve low dielectric properties and tensile properties (especially elongation).

The 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-terpinene, γ-terpinene, and monoterpenes such as sabinene, which can be used singly or in combination of two or more. Among these, monocyclic monoterpenes such as α-pinene, β-pinene, limonene, α-phellandrene, β-phellandrene, α-terpinene, and γ-terpinene are preferred, and at least one selected from the group consisting of α-pinene, β-pinene, and limonene is more preferred.

Examples of the terpene resin (B) include polyterpene resins (B1) which are homopolymers or copolymers composed of only terpene monomers, aromatic modified terpene resins (B2) which are copolymers of terpene monomers and aromatic monomers, and terpene phenol resins (B3) which are copolymers of terpene monomers and phenolic monomers. Any one of these may be used, or two or more thereof may be used in combination.

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

Examples of phenol-based monomers constituting the terpene phenol resin (B3) include phenol, cresol, and xylenol.

Preferred 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, aromatic modified terpene resin (B2) which is a copolymer of at least one terpene monomer and styrene selected from the group consisting of α-pinene, β-pinene and limonene, α-pinene, β-pinene and limonene. and a terpene phenol resin (B3) which is a copolymer of at least one terpene monomer selected from the group consisting of phenol and phenol.

The content of the terpene resin (B) is 5 to 60 parts by mass with respect to 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 10 parts by mass or more, more preferably 15 parts by mass or more, and still more preferably 20 parts by mass or more. The content of the terpene resin (B) is preferably 50 parts by mass or less, and may be 45 parts by mass or less.

[Other ingredients]
In the first component, in addition to each component described above, various additives such as catalysts, antioxidants, foam stabilizers, diluents, flame retardants, ultraviolet absorbers, colorants, fillers, and plasticizers can be added as long as the purpose of the present embodiment is not impaired.

Examples of catalysts that can be used include metal catalysts such as organotin catalysts, organolead catalysts and organobismuth catalysts, and various urethane polymerization catalysts such as amine catalysts.

<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), and any one of these may be used or two or more 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, Nylene diisocyanate, and modified and polynuclear compounds thereof.

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

Alicyclic polyisocyanates (C3) include, for example, 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 compounds thereof.

Examples of the above modified compounds include isocyanurate modified products, allophanate modified products, burette modified products, adduct modified products, carbodiimide modified products and the like.

In one embodiment, polyisocyanate (C) preferably comprises aromatic polyisocyanate (C1). By using the aromatic polyisocyanate (C1), the effect of improving the tensile properties can be enhanced. More preferably, the polyisocyanate (C) is at least one selected from the group consisting of diphenylmethane diisocyanate, its modified form and polynuclear form.

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

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

The ratio of the polyisocyanate (C) to the polyol (A) is not particularly limited, and for example, the NCO/OH (index) may be 0.6 to 1.5, 0.7 to 1.4, 0.8 to 1.3, or 0.9 to 1.2. Here, NCO/OH is the molar ratio of isocyanate groups contained in polyisocyanate (C) to hydroxy groups contained in 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 in accordance with JIS K1603-1:2007 A method.

[Other ingredients]
The second component may be composed of polyisocyanate (C) alone, and in addition to polyisocyanate (C), various additives such as catalysts, antioxidants, foam stabilizers, diluents, flame retardants, ultraviolet absorbers, colorants, fillers, and plasticizers may be added as long as the purpose of the present embodiment is not impaired.

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

The two-component curable polyurethane resin composition can be produced 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. The first component and the second component filled in separate containers may be mixed at the time of use to form a polyurethane resin by reacting the polyol (A) and the polyisocyanate (C), 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 liquid before curing, or may be cured.

<Polyol composition>
A 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 polyol (A) and terpen resin (b), and polyol (A) contains polyvodadiem polyol and / or water -contained polybidadiolior (A1), and the polyol (A) has a further 7 to 9 carbon (A). The alkillen polyol (A2) contains 4 to 15 % by mass, and the content of the terpen resin (b) is 5 to 60 parts for 100 parts by mass of polyol (A). The details of the polyol (A), the terpene resin (B) and other components are as described above, and their description is omitted.

<Application of two-component curing type 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 parts. Examples of electrical and electronic components include transformers such as transformer coils, choke coils and reactor coils, equipment control boards, sensors, and wireless communication components. The two-part curable polyurethane resin composition has excellent low dielectric properties (that is, it has a low dielectric constant) and is less susceptible to radio waves. Therefore, the two-component curable polyurethane resin composition is preferably used as a sealing material for resin-sealing, that is, covering wireless communication parts for wireless communication in order to protect the wireless communication parts from the external environment. For example, it may be used as a sealing material for a sensor that transmits detected information by wireless communication.

Electrical and electronic components resin-sealed using the two-part curable polyurethane resin composition according to the present embodiment can be used, for example, in electric washing machines, toilet seats, water heaters, water purifiers, baths, dishwashers, solar panels, power tools, automobiles, motorcycles, and the like.

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

Raw materials used in Examples and Comparative Examples are shown below.

[Polyol (A)]
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, manufactured by Idemitsu Kosan Co., Ltd. Hydrogenated polybutadiene polyol: hydroxyl value 49 mgKOH/g, product name: KRASOL H-LBH-2000, manufactured by Clay Valley Co. Octanediol: 2-ethyl-1,3-hexanediol, Product name: Octanediol, manufactured by KH Neochem Co., Ltd. Trimethylolpropane: manufactured by Tokyo Chemical Industry Co., Ltd., product code T0480
・ 1,10-Decanediol: manufactured by Tokyo Chemical Industry Co., Ltd., product code D0014
・ Ethylene glycol: manufactured by Nacalai Tesque Co., Ltd., product code 15208-95
· 1,4-butanediol: manufactured by Nacalai Tesque Co., Ltd., product code 05922-35
・ Castor oil-based polyol: hydroxyl value 160 mgKOH / g, product name: castor oil, manufactured by Ito Oil 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: Daimaron, manufactured by Yasuhara Chemical Co., Ltd. ・Terpene resin 3: phenol-α-pinene copolymer, active ingredient 100% by mass, product name: YS POLYSTER T80, Yasu Made by Hara Chemical Co., Ltd.

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

[Examples 1 to 12 and Comparative Examples 1 to 7]
Two-component curable polyurethane resin compositions of each example and each comparative example were prepared according to the formulations (parts by mass) shown in Tables 1 and 2 below. For the preparation, a predetermined amount of the first component shown in Tables 1 and 2 was weighed, and stirred and mixed while being melted by heating appropriately. After mixing, the temperature was adjusted to 25°C. Subsequently, the second component (polyisocyanate (C)) adjusted to 25° C. was added to the mixture as shown in Tables 1 and 2, and the mixture was stirred and mixed to degas.

Compatibility, adhesion, dielectric constant, tensile strength, and elongation were measured and evaluated for each two-part curable polyurethane resin composition. The measurement and evaluation methods are as follows.

[Compatibility]
Using the liquid after mixing the first component, two 3 cm diameter screw vials (No. 7 manufactured by Maruem Co., Ltd.) were poured so that one had a height of 10 cm and the other had a height of 1 cm. Each screw tube bottle was placed on a sheet of paper printed with the letter "S" (MS Gothic, 12 points), and compatibility was evaluated in the following three grades from A to C by viewing the letters from above. For those in which separation occurred in the first component after preparation, the compatibility between the polyol and the resin was poor, and subsequent measurement and evaluation as a two-component curable polyurethane resin composition could not be performed. Therefore, the evaluation result was described as D in the table, and the subsequent evaluation was not performed. Incidentally, if the evaluation is C or higher, it can be said to have practical compatibility.
A: Transparent (The characters written below can be read in both 10 cm and 1 cm screw-type bottles.)
B: Slightly turbid (I can not read the letters written under the screw bottle with a height of 10 cm, but I can read the letters written under the screw bottle with a height of 1 cm)
C: Cloudy (I can't read the letters written on the bottom of both 10 cm and 1 cm screw-type vials)

[Adhesion]
On a commercially available FR-4 epoxy substrate, the degassed two-pack curable polyurethane resin composition was dropped about 1 cm in diameter, cured at 80° C. for 16 hours (overnight) and cured. 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. Cohesive failure was defined as the state in which the polyurethane resin part remained on the substrate, and interfacial peeling was defined as the state in which the polyurethane resin was peeled off from the substrate. In addition, if the evaluation is D or higher, it can be said to have practical adhesion.
A: 100% cohesive failure
B: Cohesive failure is 75% or more and less than 100%, interfacial delamination is 0% or more and 25% or less C: Cohesive failure is 50% or more and less than 75%, interfacial delamination is 25% or more and 50% or less D: Cohesive failure is 25% or more and less than 50%, interfacial delamination is 50% or more and 75% or less E: Cohesive failure is less than 25%, interfacial delamination is 75% or more

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

[Tensile strength, elongation]
The defoamed two-pack curable polyurethane resin composition was poured into a mold having a thickness of 3 mm and cured at 80° C. for 16 hours (overnight) to prepare a resin sheet having a thickness of 3 mm. The resin sheet was punched into a dumbbell-shaped No. 3 mold to obtain a sample for measurement. The measurement was performed three times with a tensile speed of 500 mm/min and a distance between chucks of 40 mm using an apparatus manufactured by Shimadzu Corporation (body model: AG-X Plus, name: Shimadzu Precision Universal Testing Machine Autograph), and the average value of tensile strength (breaking stress) and elongation (breaking elongation) was calculated and evaluated according to the following criteria.
(Evaluation criteria for tensile strength)
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 E: Tensile strength is less than 1.5 MPa (elongation rate evaluation criteria)
A: Elongation is 130% or more B: Elongation is 110% or more and less than 130% C: Elongation is 90% or more and less than 110% D: Elongation is 70% or more and less than 90% E: Elongation is less than 70%

The results are shown in Tables 1 and 2. In Comparative Example 1, the combined use of the PB polyol (A1) and the terpene resin (B) resulted in excellent compatibility, low dielectric properties and excellent adhesion to the substrate, but the alkylene polyol (A2) was not blended, so the tensile strength and elongation were low and the tensile properties were poor.

In contrast, in Examples 1 to 12 in which the alkylene polyol (A2) was added, compatibility, adhesion and low dielectric properties were obtained, and the tensile properties could be further improved. In particular, Examples 1, 4 to 12 are excellent in compatibility, adhesion and low dielectric properties, and are excellent in the effect of improving tensile properties, and Examples 1, 5, 7 to 11 are even more excellent. In Example 3, the tensile strength was evaluated as D, but the elongation rate was evaluated as A, which was excellent, and the effect of improving the tensile properties as a whole was recognized.

In Comparative Examples 2 to 5, trimethylolpropane, decanediol, ethylene glycol or butanediol, which is another alkylene polyol, was added instead of the alkylene polyol (A2) having 7 to 9 carbon atoms. In these comparative examples, the compatibility was impaired, or the effect of improving the tensile properties was not obtained even in Comparative Example 3, which had good compatibility.

It should be noted that the various numerical ranges described in the specification can be arbitrarily combined with their upper and lower limits, and all combinations thereof are described in this specification as preferred numerical ranges. Further, the description of the numerical range "X to Y" means X or more and Y or less.

Although several embodiments of the invention have been described above, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments, their omissions, replacements, modifications, etc., are included in the invention described in the scope of claims and equivalents thereof, as well as being included in the scope and gist of the invention.

Claims (7)

a first component comprising a polyol and a terpene resin;
a second component comprising a polyisocyanate;
The polyol contains 40% by mass or more of polybutadiene polyol and/or hydrogenated polybutadiene polyol,
The polyol further contains 4 to 15% by mass of an alkylene polyol having 7 to 9 carbon atoms,
A two-pack curable polyurethane resin composition, wherein the content of the terpene resin is 5 to 60 parts by mass with respect to 100 parts by mass of the polyol. 2. The two-part curable polyurethane resin composition according to claim 1, wherein said alkylene polyol is a diol having a hydroxy group bonded to a primary carbon atom and a hydroxy group bonded to a secondary carbon atom. The two-part curable polyurethane resin composition according to claim 1 or 2, wherein the polyisocyanate contains an aromatic polyisocyanate. The two-component curable polyurethane resin composition according to any one of claims 1 to 3, wherein the polyol further contains a castor oil-based polyol. The two-component curable polyurethane resin composition according to any one of claims 1 to 4, which is for sealing electric and electronic parts. An electric/electronic component resin-sealed using the two-component curable polyurethane resin composition according to any one of claims 1 to 5. A polyol composition used as a polyol component of a two-component curable polyurethane resin composition,
including polyols and terpene resins,
The polyol contains 40% by mass or more of polybutadiene polyol and/or hydrogenated polybutadiene polyol,
The polyol further contains 4 to 15% by mass of an alkylene polyol having 7 to 9 carbon atoms,
The polyol composition, wherein the content of the terpene resin is 5 to 60 parts by mass with respect to 100 parts by mass of the polyol.