JP6980554B2 - Polyurethane resin composition, molded article using it, and electrical and electronic parts - Google Patents

Description

The present invention relates to a polyurethane resin composition using at least castor oil-based polyol as a hydroxyl group-containing compound, a molded body made of this polyurethane resin composition, and an electric / electronic component provided with the molded body.

Conventionally, polyurethane resin has been preferably used as a coating material or a sealing material in electrical and electronic parts such as transformers, capacitors, discharge stabilizers, in-vehicle electrical components, in-vehicle sensors, and electronic substrates. By covering or sealing the electrical and electronic components with polyurethane resin, the electrical and electronic components can be electrically insulated, protected from physical influences (for example, vibration or shock, etc.) on the electrical and electronic components, or the electrical and electronic components can be protected. It is possible to realize protection of material influences (for example, moisture or dust, etc.) from the surrounding environment.

The polyurethane resin can be produced with a wide variety of properties depending on the type and combination of the hydroxyl group-containing compound (polyol compound) and the isocyanate compound as raw materials, the combined use of other functional groups, and the like. Among these various polyurethane resins, those using a castor oil-derived compound as a raw material are known to be useful as a coating material or a sealing material for electrical and electronic parts. This is because the polyurethane resin using the castor oil-derived compound not only has good insulating properties, but is also relatively inexpensive, and since it is a plant-derived raw material, it improves the biomass level and reduces the environmental load. Because it can also be done.

By the way, with respect to polyurethane resins for electric and electronic parts, the density of the electric and electronic parts or the electric and electronic products using the electric and electronic parts is being reduced for the purpose of weight reduction or cost reduction. Therefore, a foam (foam) is preferably used as the polyurethane molded body included in the electric / electronic component. The applicant of the present application has prepared an isocyanate group-terminated prepolymer obtained by reacting MDI (diphenylmethane diisocyanate) with castor oil as an isocyanate compound as disclosed in Patent Document 1 as a polyurethane resin composition for electrical and electronic parts. We are proposing the foam type polyurethane resin composition used.

According to the study of the applicant of the present application, when water is used as the foaming agent, the polyurethane foam shrinks over time if the closed cell ratio remains high, and the water permeability of the polyurethane foam increases if the closed cell ratio is lowered. It became clear that it became high and sufficient electrical insulation could not be obtained. The polyurethane resin composition disclosed in Patent Document 1 can achieve both low closed cell ratio and low water permeability (and sufficient electrical insulation) when molded as a polyurethane foam, and thus is used for electrical and electronic parts. It can be suitably used as a material.

Japanese Patent No. 5761879

In recent years, there has been a tendency for further improvement in physical properties of polyurethane resin compositions for electrical and electronic components. For example, in a molded product that is a coating material or a sealing material, it is preferable that not only the water permeability is low but also that the molded product does not easily shrink after molding (has non-shrinkability). For example, as the integration of electrical and electronic components progresses, the structure will also become finer, but the degree of shrinkage of the molded product, which has not been a problem in the past, will be reduced to the fine structure of the highly integrated electrical and electronic components. May affect. Therefore, especially in polyurethane resin compositions for electrical and electronic components, it is required to have not only low water permeability but also good non-shrinkability.

The present invention has been made to solve such a problem, and is a polyurethane resin composition that can be suitably used for electrical and electronic component applications and can realize good non-shrinkage as well as low water permeability. The purpose is to provide things.

The polyurethane resin composition according to the present invention is a polyurethane resin composition obtained by reacting at least (A) a hydroxyl group-containing compound, (B) an isocyanate compound, and (C) water in order to solve the above-mentioned problems. As the (A) hydroxyl group-containing compound, (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol are used, and the (A-2) polybutadiene is used. The mixing ratio ((A-1) / (A-2)) of the (A-1) castor oil-based polyol to the polyol is 50 or less in terms of mass ratio.

According to the above configuration, (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol are used as (A) hydroxyl group-containing compound, and (A-2). By reducing the mixing ratio of the (A-1) castor oil-based polyol to the polybutadiene polyol to half or less in terms of mass ratio, not only can the water permeability of the obtained polyurethane molded product be relatively low, but also the water permeability of the molded product can be made relatively low. It is possible to effectively suppress shrinkage and achieve good non-shrinkage. As a result, not only good electrical insulation can be realized, but also the degree of shrinkage of the molded body is small, so even if the electric / electronic component contains a fine structure, the influence on the structure etc. is effectively effective. It can be suppressed. As a result, it is possible to obtain a polyurethane resin composition that can be particularly suitably used for electrical and electronic component applications.

In the polyurethane resin composition according to the present disclosure, the mixing ratio ((A-1) / (A-2)) of the (A-1) castor oil-based polyol to the (A-2) polybutadiene polyol is the mass ratio. It may be configured to be 1 or more.

Further, in the polyurethane resin composition according to the present disclosure, the mixing ratio of the total amount of the (A-1) castor oil-based polyol and the (A-2) polybutadiene polyol to the (A-3) amine polyol (((A-2) polybutadiene polyol). A-1) + (A-2)) / (A-3)) may be configured to have a mass ratio of 1 or more.

Further, in the polyurethane resin composition according to the present disclosure, the mixing ratio of the total amount of the (A-1) castor oil-based polyol and the (A-2) polybutadiene polyol to the (A-3) amine polyol (((A-2) polybutadiene polyol). A-1) + (A-2)) / (A-3)) may be configured to have a mass ratio of 55 or less.

Further, in the polyurethane resin composition according to the present disclosure, the mixed amount of the (C) water is 100 mass by mass of the (A) hydroxyl group-containing compound, the (B) isocyanate compound, and the (C) water. The composition may be in the range of 0.1 to 1.2% by mass when it is defined as%.

Further, the polyurethane resin composition according to the present disclosure may have a configuration for electrical and electronic parts.

The molded product according to the present disclosure may be any product made of the polyurethane resin composition having the above-mentioned constitution. Further, the electrical and electronic parts according to the present disclosure may be any as long as they include a molded body made of the polyurethane resin composition having the above-mentioned constitution.

The present invention has the effect that it is possible to provide a polyurethane resin composition that can be suitably used for electrical and electronic component applications and can realize good non-shrinkability as well as low water permeability by the above configuration. Play.

The polyurethane resin composition according to the present disclosure is obtained by reacting (A) a hydroxyl group-containing compound, (B) an isocyanate compound, and (C) water. As the (A) hydroxyl group-containing compound, (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol are used, and these 3 are used in the reaction of each of these components. The mixing ratio (blending ratio) of the type (A) hydroxyl group-containing compound is optimized.

Specifically, in the polyurethane resin composition according to the present disclosure, the mixing ratio of (A-1) castor oil-based polyol to (A-2) polybutadiene polyol ((A-1) / (A-2)) is , The mass ratio may be 50 or less, but the mixing ratio ((A-1) / (A-2)) is preferably 1 or more by mass ratio, and further, (A-3) amine polyol. (A-1) + (A-2)) / (A-3)) of the total amount of (A-1) castor oil-based polyol and (A-2) polybutadiene polyol is preferred. Is more preferable. Hereinafter, typical embodiments of the present invention will be described.

[(A) Hydroxyl group-containing compound]
In the polyurethane resin composition according to the present disclosure, the raw material (A) hydroxyl group-containing compound includes (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) as described above. ) Three types of amine polyols are used as essential components.

(A-1) The castor oil-based polyol may be a polyol having a castor oil fatty acid ester structure in the molecule. (A-1) The specific type of the castor oil-based polyol is not particularly limited, and typical examples thereof include castor oil or castor oil derivative polyols synthesized using castor oil fatty acid. Specific examples of the persimmon oil derivative polyol include, for example, a transesterification reaction product of castor oil and a polyol, a transesterification reaction product to which an alkylene oxide is added, and esterification of a castor oil fatty acid and a polyol. Examples thereof include a reaction product and a product obtained by adding an alkylene oxide to this transesterification reaction product, but the present invention is not particularly limited.

As the (A-1) castor oil-based polyol used as a raw material in the polyurethane resin composition according to the present disclosure, only one type is selected and used from the above-mentioned compounds (or other castor oil-based polyols not exemplified). Alternatively, two or more kinds of compounds may be appropriately selected and used in combination.

(A-2) The polybutadiene polyol may be a polyol having a polybutadiene structure in the molecule. Specifically, for example, a polyol having a polybutadiene structure in which 1,3-butadiene is trans-bonded 1,4, a polyol having a polybutadiene structure in which 1,3-butadiene is cis 1,4 bonded, and 1,3-butadiene are 1 , A polyol having a polybutadiene structure having two bonds, a polyol having a polybutadiene structure in which these bonds are mixed, and the like can be mentioned, but the present invention is not particularly limited. Further, these polyols may have hydroxyl groups at both ends of the polybutadiene structure in the molecule, or the polybutanediene structure may be chain-like.

As the (A-2) polybutadiene polyol used as a raw material in the polyurethane resin composition according to the present disclosure, only one kind may be selected and used from the above-mentioned compounds (or other polybutadiene polyols not exemplified). Two or more kinds of compounds may be appropriately selected and used in combination.

(A-3) The amine polyol may be a tertiary amine having a plurality of hydroxyl groups in the molecule. Representatively, an aromatic amine polyol or an aliphatic amine polyol can be mentioned. (A-3) By using an aromatic amine polyol and / or an aliphatic amine polyol as the amine polyol, it is possible to improve the long-term stability of the polyol mixture described later.

Examples of the aromatic amine polyol include aromatic amines such as aniline, toluenediamine, diethyltoluenediamine, 4,4'-diamino-3, 3'-diethyldiphenylmethane, to which alkylene oxide is added, and Mannig-based polyols. It can be, but it is not particularly limited. Examples of the aliphatic amine polyol include those obtained by adding an alkylene oxide to an aliphatic amine such as ethylenediamine, hexamethylenediamine, and diethylenetriamine, but the present invention is not particularly limited. Of these, the Mannich-based polyol is particularly preferable as the aromatic amine polyol, and the aliphatic amine polyol in which alkylene oxide is added to ethylenediamine is particularly preferable.

As the (A-3) amine polyol used as a raw material in the polyurethane resin composition according to the present disclosure, only one of the above-mentioned compounds (or other amine polyols not exemplified) may be selected and used. Two or more kinds of compounds may be appropriately selected and used in combination.

In the present disclosure, as the (A) hydroxyl group-containing compound, the above-mentioned (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol may be used. As illustrated in Examples or Reference Examples described later, the hydroxyl group-containing compound is 3 of (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol. It may be composed of only types. Further, in the present disclosure, the (A) hydroxyl group-containing compound may contain a compound other than these three types. Further, in the present disclosure, even if the compound is classified as (A) a hydroxyl group-containing compound, it is a specific compound in the polyol mixture or all the components used in the reaction, depending on various conditions such as the physical properties of the obtained molded product. It is possible to eliminate the compounding of.

[(B) Isocyanate compound]
In the polyurethane resin composition according to the present disclosure, the isocyanate compound (B) as a raw material may be a compound having a plurality of isocyanate groups in the molecule. Specifically, the compound is not particularly limited as long as it is a compound capable of reacting with the above-mentioned (A) hydroxyl group-containing compound to form a polyurethane, but representatively, an aliphatic polyisocyanate, an alicyclic polyisocyanate, and the like. Examples thereof include aromatic polyisocyanates and aromatic aliphatic polyisocyanates.

Examples of the aliphatic polyisocyanate include tetramethylene diisocyanate, dodecamethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, and 2-methylpentane. Examples thereof include -1,5-diisocyanate and 3-methylpentane-1,5-diisocyanate, but the present invention is not particularly limited.

Examples of the alicyclic polyisocyanate include isophorone diisocyanate, hydrogenated xylylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4-cyclohexanediisocyanate, methylcyclohexylene diisocyanate, and 1,3-bis (isocyanatemethyl) cyclohexane. It can be mentioned, but it is not particularly limited.

Examples of the aromatic polyisocyanate include tolylene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate, 4,4'-. Examples thereof include dibenzyl diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate, 1,3-phenylenedi isocyanate, and 1,4-phenylenedi isocyanate, but the present invention is not particularly limited.

Examples of the aromatic aliphatic polyisocyanate include dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, α, α, α, α-tetramethylxylylene diisocyanate and the like, but are not particularly limited.

Further, as the (B) isocyanate compound, a modified carbodiimide, alohanate, burette, isocyanurate, adduct, etc. of the above-mentioned organic polyisocyanate (or other isocyanate compound not exemplified) may be used. can.

Further, the isocyanate compound (B) used as a raw material in the polyurethane resin composition according to the present disclosure may be a prepolymer or may not be a prepolymer. That is, the (B) isocyanate compound may be the above-mentioned organic polyisocyanate (or other isocyanate compound not exemplified), or the above-mentioned organic polyisocyanate or the like and an arbitrary (A) hydroxyl group-containing compound are excessive in isocyanate groups. It may be one that has been reacted under conditions (prepolymer).

As the (B) isocyanate compound used as a raw material in the polyurethane resin composition according to the present disclosure, only one of the above-mentioned compounds (or other isocyanate compounds not exemplified) may be selected and used. More than one kind of compounds may be appropriately selected and used in combination. Further, in the present disclosure, even if the compound is classified as (B) isocyanate compound, the compounding of a specific compound is excluded from all the components used in the reaction depending on various conditions such as the physical properties of the obtained molded product. can do.

[(C) Water and other ingredients]
The polyurethane resin composition according to the present disclosure may be at least obtained by reacting (C) water in addition to the above-mentioned (A) hydroxyl group-containing compound and the above-mentioned (B) isocyanate compound. (C) Water functions as a foaming agent for foaming the obtained polyurethane resin composition in the reaction of the (A) hydroxyl group-containing compound and the (B) isocyanate compound.

Further, in the production of the polyurethane resin composition according to the present disclosure, other components may be used in addition to (A) a hydroxyl group-containing compound, (B) an isocyanate compound, and (C) water. Specific examples of other components include catalysts, defoamers, fillers, surfactants, antioxidants, flame retardants, antifungal agents, deodorants, dispersants, discoloration inhibitors, and plasticizers. , Known additives such as fragrances, but are not particularly limited. Among these, it is preferable to use (D) a catalyst from the viewpoint of accelerating the reaction of (A) a hydroxyl group-containing compound and (B) an isocyanate compound.

The specific type of the catalyst (D) used in the production of the polyurethane resin composition according to the present disclosure is not particularly limited, and various catalysts known in the field of polyurethane resin production (polyurethane synthesis) can be used. .. Specific catalysts include, for example, triethylenediamine, triethylamine, tri-n-butylamine, N-methylmorpholin, dimethylethanolamine, bis (2-dimethylaminoethyl) ether, N, N, N', N'-tetra. Tertiary amines such as methylhexamethylenediamine, N, N, N', N'', N''-pentamethyldiethylenetriamine, 1,2-dimethylimidazole; organic salts of metals and organic acids, organic chelate compounds, etc. Metal compounds; etc.

Examples of the metal constituting the metal and the metal salt of the organic acid include zinc, tin, lead, zirconium, bismuth, cobalt, manganese, iron and the like, but are not particularly limited. Further, examples of the organic acid constituting the metal salt of the metal and the organic acid include octene acid and naphthenic acid, but are not particularly limited.

Examples of the metal chelate compound include dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin diacetylacetonate, zirconium tetraacetylacetonate, titanium acetylacetonate, acetylacetone aluminum, acetylacetone cobalt, acetylacetone iron, acetylacetone copper, and acetylacetone zinc. It can be, but it is not particularly limited.

As the catalyst (D) used in the production of the polyurethane resin composition according to the present disclosure, only one kind may be selected and used from the above-mentioned compounds (or compounds or substances having other catalytic functions not exemplified). Alternatively, two or more kinds of compounds and the like may be appropriately selected and used in combination. Further, in the present disclosure, although substances classified into other components including (D) catalyst may be used, in all the components used in the reaction depending on various conditions such as the physical characteristics of the obtained molded product. It is possible to eliminate the formulation of specific substances.

[Polyurethane resin composition]
The polyurethane resin composition according to the present disclosure may be obtained by reacting at least each of the above-mentioned components (A) to (C) as a raw material, and the component (A) is (A-). 1) Castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol may be used as essential components. Therefore, in the present disclosure, the specific blending amounts of the components (A) to (C) and the other components (including the catalyst (D)) in the reaction are not particularly limited.

In the polyurethane resin composition according to the present disclosure, the typical compounding amounts of the components (A) to (C) during the reaction are the essential components (A) hydroxyl group-containing compound, (B) isocyanate compound, and ( C) The total mass of water will be described as "total mass of raw materials". First, the preferable blending amount of the (A) hydroxyl group-containing compound may be in the range of 15 to 80 parts by mass with respect to 100 parts by mass of the total raw material, and may be in the range of 20 to 70 parts by mass. More preferred. Further, the preferable blending amount of the (B) isocyanate compound may be in the range of 20 to 85 parts by mass with respect to 100 parts by mass of the total raw material, and more preferably in the range of 25 to 80 parts by mass. preferable. When the blending amount of the (A) hydroxyl group-containing compound or (B) isocyanate compound in the total mass of the raw material is within the above range, the moldability of the polyurethane resin composition can be further improved.

The preferable blending amount of (C) water may be in the range of 0.1 to 1.2 parts by mass with respect to 100 parts by mass of the total weight of the raw material, and is 0.2 to 1.1 parts by mass. It is more preferably within the range, and more preferably within the range of 0.3 to 1.0 parts by mass. (C) When the blending amount of water is within this range, the water permeability, electrical insulation, and shock absorption of the obtained molded product and the moldability of the polyurethane resin composition can be further improved. can.

When the catalyst (D) may be blended as other components in addition to the essential components (A) to (C), the preferable blending amount of the catalyst (D) is the total weight of the raw materials. It can be mentioned in the range of 0.01 to 5.0 parts by mass with respect to 100 parts by mass, and more preferably in the range of 0.1 to 3.0 parts by mass. When the blending amount of the catalyst (D) is within this range, the reactivity of the hydroxyl group-containing compound (A) and the isocyanate compound (B) can be made better, and the moldability of the polyurethane resin composition is suitable. Can be.

In other words, in the polyurethane resin according to the present disclosure, the preferable blending ratio of each component can be described as a percentage, with the total mass of the components (A) to (C) as essential components being 100% by mass. First, the compounding ratio of the (A) hydroxyl group-containing compound is preferably in the range of 15 to 80% by mass, more preferably in the range of 20 to 70% by mass. The compounding ratio of the (B) isocyanate compound is preferably in the range of 20 to 85% by mass, more preferably in the range of 25 to 80% by mass. The mixing ratio of (C) water is preferably in the range of 0.1 to 1.2% by mass, preferably in the range of 0.2 to 1.1% by mass, and preferably in the range of 0.3 to 1.0% by mass. The range of is more preferable.

Here, the compounding ratio of the above-mentioned components (A) to (C) is a ratio within 100% by mass of the total mass of these essential components, but a preferable compounding ratio of other components such as (D) a catalyst is essential. It can be positioned as the ratio of "external addition" to 100% by mass of the total mass of the components (A) to (C).

The preferable compounding ratio of the catalyst (D) is preferably 0.1 to 3.0 when the total weight of the raw material is 100% by mass, preferably in the range of 0.01 to 5.0% by mass. It is more preferable to add it externally within the range of mass%. For example, when 0.01% by mass of the catalyst (D) is externally added to 100% by mass of the total mass of the raw material, the percentage of all the components (components (A) to (D)) in the reaction is 100.01% by mass. Become.

Here, in the present disclosure, since the above-mentioned three types of polyols are used as the (A) hydroxyl group-containing compound, it is particularly necessary to mix these polyols so as to satisfy a predetermined mixing ratio condition (mixing condition). preferable. Specific mixing conditions include mixing condition 1 which is a mixing ratio of (A-1) castor oil-based polyol to (A-2) polybutadiene polyol ((A-1) / (A-2)) and (A). -3) Mixing ratio of the total amount of the (A-1) castor oil-based polyol and the (A-2) polybutadiene polyol to the amine polyol ((A-1) + (A-2)) / (A-3) )) The mixing condition 2 can be mentioned. All of these mixing conditions are mass ratios.

In the present disclosure, at least the upper limit under the mixing condition 1 is defined when reacting each component (A) to (C) (or in the composition of the polyol mixture). That is, in the production of the polyurethane resin composition according to the present disclosure (reaction of the components (A) to (C)) (or in the polyol mixture described later), the mass ratio (A-1) / (A-2) is determined. The (A-1) castor oil-based polyol and the (A-2) polybutadiene polyol may be mixed so as to be 50 or less ((A-1) / (A-2) ≦ 50). As a result, in the obtained molded product, the water permeability (water absorption rate) can be lowered and the non-shrinkability can be improved (the obtained molded product can be made difficult to shrink) (described later). See Comparative Example 4).

Further, although the lower limit of the mixing condition 1 is not particularly limited, ((A-1) / (A-2) ≧ 1) so that the mass ratio (A-1) / (A-2) is 1 or more ((A-1) / (A-2) ≧ 1). A-1) Castor oil-based polyol and (A-2) Polybutadiene polyol may be mixed. As a result, in the obtained molded product, not only the low water permeability and non-shrinkability can be improved, but also the closed cell ratio thereof can be improved, and the appearance of the molded product can be improved. Yes (see Reference Example 1 below).

In Patent Document 1, in the obtained molded product, both lowering the closed cell ratio and lowering the water permeability are achieved at the same time. However, as a result of further diligent studies by the inventors of the present application, it has become clear that it is better to increase the closed cell ratio from the viewpoint of further lowering the water permeability in response to recent demands. Therefore, in the present invention, the closed cell ratio is improved as compared with Patent Document 1.

Here, in the present disclosure, the appearance of the obtained molded product is visually observed as evaluated in Examples and the like described later, but in this observation, the presence or absence of shrinkage disclosed in Patent Document 1 (presence or absence of shrinkage) Not only the non-shrinkability evaluation), but also whether the cells on the surface of the molded body are rough and whether the surface of the molded body is rough are evaluated. In other words, the roughness of the cells on the surface of the molded product and the state of the surface roughness can be said to be whether or not the homogeneity of the surface of the molded product is good.

The non-shrinkability of the molded body may affect the structure of the electric / electronic component when the molded body constitutes a part of the structure of the electric / electronic component (for example, a coating layer or a sealing portion). .. For example, if the molded body to be the coating layer or the sealing portion shrinks too much, the fine structure of the electric / electronic component may be impaired. Further, if the homogeneity of the surface of the molded product is not good, there is a concern that the adhesion or the electric insulation property may be affected at the coated portion or the sealing portion of the electric / electronic component. Therefore, it is preferable that the surface of the molded product has good homogeneity. When the mixing condition 1 is satisfied in the production of the polyurethane resin composition (or in the composition of the polyol mixture), the surface of the polyurethane molded product according to the present disclosure can realize good homogeneity.

Further, in the present disclosure, it is preferable to satisfy the mixing condition 2 in addition to the mixing condition 1 when producing the polyurethane resin composition (or in the composition of the polyol mixture). The mass ratio (A-1) + (A-2)) / (A-3), which is the mixing condition 2, may be 1 or more and 55 or less. Even if the lower limit of the mixing condition 2 is less than 1, the non-shrinkability, closed cell ratio, surface homogeneity, etc. of the molded product can be improved, but the hardness of the molded product is high depending on various conditions. It tends to be too much. If the hardness of the molded product becomes too high, the structure may be damaged or peeled off, solder cracks, etc. may occur when the electrical and electronic parts are coated or sealed (Reference Example 2 to be described later). reference). Further, even if the upper limit of the mixing condition 2 exceeds 55, the non-shrinkability, closed cell ratio, surface homogeneity, hardness, etc. of the molded product can be improved, but the long-term stability of the polyol mixture described later can be improved. It becomes impossible to realize the sex (see Reference Example 3 described later).

[Manufacturing method of polyurethane resin composition]
The method for producing the polyurethane resin composition according to the present disclosure is not particularly limited, and each component (A) to (C) described above is mixed by a known mixing device (mixer or the like), and various conditions are met as necessary. It may be set and each component of (A) to (C) may be reacted. For the production of the polyurethane resin composition, a mixture of each component (or a part thereof) of (A) to (C) is referred to as a "raw material mixture" for convenience of explanation.

In the production of the polyurethane resin composition according to the present disclosure, a raw material mixture in which each component (A) to (C) (if necessary, other components such as a catalyst (D)) is mixed and mixed, that is, "1". A "liquid type" raw material mixture may be prepared (manufactured). Alternatively, a raw material mixture in which (A) a hydroxyl group-containing compound and (B) an isocyanate compound are prepared separately and mixed immediately before the production (molding) of the molded product (straight line used), that is, a “two-component” raw material. The mixture may be prepared (manufactured).

In the present disclosure, as described above, three types of (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol are used in combination as the component (A). Therefore, in the present disclosure, if the polyurethane resin composition is a "two-component type", the (A) hydroxyl group-containing compound is a polyol mixture (or a polyol composition or a hydroxyl group) in which at least these three types of polyols are mixed in advance. The contained compound composition) may be prepared.

Further, in Examples and Reference Examples described later, in addition to (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol, (C) water as a foaming agent is used. (D) A polyol mixture is prepared by mixing with a catalyst. When the (B) isocyanate compound is mixed with other components, it may be referred to as "isocyanate mixture (or isocyanate composition)" for convenience, as in the case of the polyol mixture. Further, when other components may be blended in addition to the catalyst (D), the other components may be blended in the polyol mixture or the isocyanate mixture depending on the type thereof.

As shown in Comparative Examples 1 to 3 described later, when only (A-1) castor oil-based polyol is used as the raw material (A) component in the production of the polyurethane resin composition, the molded product tends to shrink. (See Comparative Example 2). Further, when only the (A-2) polybutadiene polyol is used as the component (A), the water permeability (water absorption rate) of the molded product becomes high (see Comparative Example 1).

On the other hand, it is clear that when (A-1) castor oil-based polyol and (A-2) polybutadiene polyol are used in combination, shrinkage of the molded product can be effectively suppressed and water permeability (water absorption rate) can also be effectively suppressed. became. However, when only (A-1) castor oil-based polyol and (A-2) polybutadiene polyol are used as essential components as the component (A), the raw material mixture for producing the polyurethane resin composition is "two-component type". It was also clarified that the long-term stability (storage stability) of the polyol mixture was lowered in the case of "" (see Comparative Example 3). Therefore, as a result of further diligent studies, the long-term stability of the polyol mixture can be improved by using (A-3) amine polyol in combination with (A-1) castor oil-based polyol and (A-2) polybutadiene polyol. Was clarified (see Examples 1 to 13).

Further, when the (A-3) amine polyol is used in combination as the (A) hydroxyl group-containing compound, the hardness thereof in the obtained molded product, although it depends on the specific types of the (A) component and the (B) component. It was also clarified that can be adjusted well. (A-3) By increasing the blending amount of the amine polyol (that is, reducing the mixing condition 2), the hardness of the obtained molded product can be increased (see Reference Example 2). Therefore, by adjusting the blending amount of the (A-3) amine polyol according to the use of the polyurethane resin composition, it becomes possible to realize a suitable hardness in the obtained molded product.

Therefore, the present disclosure is a "one-component type" in which (A) a hydroxyl group-containing compound, (B) an isocyanate compound, and (C) water (if necessary, other components such as a catalyst) are blended and used. It contains not only the polyurethane resin composition obtained from the raw material mixture of the above, but also (A) a hydroxyl group-containing compound (A-1) a castor oil-based polyol, (A-2) a polybutadiene polyol, and (A-3) an amine polyol. Also included is a polyurethane resin composition obtained from a "two-component" raw material mixture that is a combination (set) of the composition (polyol mixture) and (B) isocyanate compound (or isocyanate mixture).

Further, in the polyurethane resin composition according to the present disclosure, the specific type of the (B) isocyanate compound is not particularly limited as described above. Therefore, in the present disclosure, for the purpose of obtaining a polyurethane resin composition or a polyurethane molded product, a polyol containing (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol. A mixture (polyol composition or hydroxyl group-containing compound composition) may be contained. As described above, the foaming agent (C) water and other components such as the catalyst (D) to be blended as needed may be premixed with, for example, a polyol mixture.

In the present disclosure, the evaluation of the long-term stability of the polyol mixture is not particularly limited, and the evaluation may be performed by the method described in Examples described later, or may be evaluated by other known methods. Further, in the present disclosure, the viscosity of the polyol mixture is not particularly limited, but is preferably 6000 mPa · s or less, and more preferably 5000 mPa · s or less. When the viscosity of the polyol mixture is not more than this upper limit, the handleability of the polyol mixture and the raw material mixture becomes better, and the moldability of the polyurethane resin composition can be improved. The viscosity of the polyol mixture may be measured by the measuring method described in Examples described later.

[Molded parts and electrical and electronic parts]
The polyurethane resin composition according to the present disclosure can be used for various purposes, and can be particularly preferably used for electrical and electronic component applications. A molded product made of the polyurethane resin composition according to the present disclosure, that is, a molded product (cured product or cured product) formed (cured or manufactured) by reacting the above-mentioned raw material mixture, has good electrical insulation and protective performance. As described above, good low water permeability, non-shrinkage, closed cell ratio can be realized, and further low density and good elastic modulus can be realized. Therefore, the present disclosure also includes a molded product made of the polyurethane resin composition having the above constitution. The molded product according to the present disclosure can be suitably used as a coating material or a sealing material in electrical and electronic parts.

Although specific configuration of the molded body according to the present disclosure is not particularly limited, the density is more that is preferably in a range of 100~400kg / m ^3, in the range of 120~380kg / m ³ preferable. When the density is within this range, when it is used as a covering material or a sealing material for an electric / electronic component, it is possible to suppress an increase in the weight of the electric / electronic component and contribute to weight reduction. The density of the molded product may be measured (calculated) by the method described in Examples described later.

Further, the hardness (shore A) of the molded product according to the present disclosure is preferably in the range of 1 to 80, and more preferably in the range of 10 to 70. When the hardness is within this range, when it is used as a coating material or a sealing material for an electric / electronic component, it is possible to avoid or suppress the possibility of affecting the structure or the like provided in the electric / electronic component. For example, when an electric / electronic component is an electronic substrate, if the hardness is too high, damage such as solder cracks may occur, or the structure may be peeled off. On the other hand, if the hardness of the molded product is within the above range, it is possible to realize "moderate" (good) hardness that is neither too soft nor too hard as a coating material or a sealing material. The hardness (shore A) of the molded product may be measured by the method described in Examples described later.

Further, the closed cell ratio of the molded product according to the present disclosure is preferably 50% or more, and preferably 70% or more. When the closed cell ratio is at least this lower limit, it is possible to effectively suppress the increase in water permeability when used as a coating material or a sealing material for electrical and electronic parts. Generally, when the closed cell ratio is low, the water permeability (water absorption rate) tends to be high, and when the molded body (coating material or sealing material) absorbs water, the electrical insulation property may decrease, but the molded body is good. By having the closed cell ratio, it is possible to lower the water permeability and suppress or prevent the deterioration of the electrical insulating property. Further, when the closed cell ratio is within this range, it becomes easy to set the hardness of the molded product in the “moderate” range. The closed cell ratio of the molded product may be measured (calculated) by the method described in Examples described later.

The elastic modulus of the molded product according to the present disclosure is preferably in the range of 1 to 50%, and preferably in the range of 3 to 40%. When the impact modulus is within this range, good impact absorption can be realized when used as a coating material or a sealing material for an electric / electronic component, and therefore, a coated or sealed electric / electronic component can be used. The structure can be well protected. The elastic modulus of the molded product may be measured by the method described in Examples described later.

Further, the water absorption rate of the molded product according to the present disclosure is preferably 30% or less, and preferably 20% or less. If the water absorption rate is equal to or less than this upper limit, it can be said that the water permeability of the molded body is sufficiently low. Can be satisfactorily suppressed or prevented. The water absorption rate of the molded product may be measured (calculated) by the method described in Examples described later.

Further, the method for evaluating the non-shrinkability of the molded product according to the present disclosure is not particularly limited, and as described in Examples described later, it may be visually evaluated the day after the formation (curing or manufacturing), or it is known. It may be evaluated by other methods. Generally, the polyurethane resin shrinks after the (A) hydroxyl group-containing compound reacts with the (B) isocyanate compound and is cured. Therefore, if the degree of shrinkage is large, the polyurethane resin is used as a coating material or a sealing material for electrical and electronic parts. In some cases, the structure may be damaged or peeled off. In the present disclosure, if deformation due to shrinkage cannot be visually confirmed, it can be determined that there is almost no effect on the structure of the electrical and electronic component, and it can be evaluated that the component has sufficient non-shrinkability.

The polyurethane resin composition according to the present disclosure can be suitably used for electrical and electronic component applications as described above, and the molded product according to the present disclosure is a coating material or sealing material (or other) for electrical and electronic components as described above. It can be suitably used as a structure). Therefore, the present disclosure also includes electrical and electronic components including a molded body made of the polyurethane resin composition having the above constitution. The electrical and electronic parts according to the present disclosure may be any as long as the molded body (polyurethane molded body) according to the present disclosure is provided as a covering member, a sealing member, or another member.

The specific configuration of the electric / electronic component according to the present disclosure is not particularly limited, and a known electric component or a known electronic component can be mentioned. Specific examples of electrical and electronic components include transformers, capacitors, discharge ballasts, in-vehicle electrical components, in-vehicle sensors, electronic boards, and the like. The products in which the electric and electronic parts according to the present disclosure are used are not particularly limited, but for example, electric washing machines, toilet seats, water heaters, water purifiers, baths, dishwashers, solar panels, electric tools, and various types of transportation. Equipment (mobile devices, specifically trains, automobiles, motorcycles, electric bicycles, etc.) can be mentioned. Therefore, the electrical and electronic parts according to the present disclosure may be any parts used in these products.

The method for manufacturing the electric / electronic parts according to the present disclosure is not particularly limited, and various known methods can be adopted depending on the type of the electric / electronic parts. For example, when the molded product according to the present disclosure is used as a coating material, an electric / electronic component before coating treatment is placed inside the molding die, a raw material mixture is prepared as described above, and this raw material composition is injected. By integrally molding the parts, the electric and electronic parts according to the present disclosure can be manufactured. The curing reaction temperature of the raw material composition is not particularly limited, but is preferably in the range of 15 to 120 ° C. Alternatively, a manufacturing method may be used in which a known adhesive layer is formed on a portion to be coated of the electric / electronic component before the coating treatment, and a preformed molded body is adhered.

As described above, in the polyurethane resin composition according to the present disclosure, as the raw material (A) hydroxyl group-containing compound, (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3). By using an amine polyol and reducing the mixing ratio of the (A-1) castor oil-based polyol to the (A-2) polybutadiene polyol to half or less by mass, the water permeability of the obtained polyurethane molded product is relatively low. Not only can this be done, but the shrinkage of the molded product can be effectively suppressed to achieve good non-shrinkage. As a result, not only good electrical insulation can be realized, but also the degree of shrinkage of the molded body is small, so even if the electric / electronic component contains a fine structure, the influence on the structure etc. is effectively effective. It can be suppressed. As a result, it is possible to obtain a polyurethane resin composition that can be particularly suitably used for electrical and electronic component applications.

The present invention will be described in more detail with reference to Examples, Comparative Examples and Reference Examples, but the present invention is not limited thereto. One of ordinary skill in the art can make various changes, modifications, and modifications without departing from the scope of the present invention. The physical properties of the polyol mixture and the polyurethane molded product in the following examples were measured or evaluated as shown below.

(Storage stability of polyol mixture)
The polyol mixture (mixture of (A) component, (C) component and (D) component) obtained in each Example, each Comparative Example, or each Reference Example was sealed in a storage container and kept at 25 ° C. for 90 days. It was left still. Then, it was visually observed whether or not the polyol mixture had separated. The case where separation did not occur in the polyol mixture after standing was evaluated as "◯", and the case where separation occurred was evaluated as "x".

(Viscosity of polyol mixture)
The viscosity of the polyol mixture obtained in each example, each comparative example, or each reference example is measured by a rotary viscometer (manufactured by Toki Sangyo Co., Ltd. or Tokyo Keiki Co., Ltd., trade name: B) in accordance with JIS Z-8803. It was measured using a type viscometer BM).

(Appearance of polyurethane molded product)
The appearance of the polyurethane molded product obtained in each Example, each Comparative Example, or each Reference Example was visually observed on the next day of production. When the cells on the surface of the polyurethane molded product are not rough and the surface is not rough (when the surface homogeneity is excellent), "○", when the cells on the surface are not rough but the surface is slightly rough (on the surface) The case where the homogeneity is good) is evaluated as “Δ”, and the case where the surface cells are rough and / or the surface is rough (when the surface homogeneity is low) is evaluated as “x”.

(Preparation of sample for evaluation of polyurethane molded product)
The polyurethane molded articles obtained in each Example, each Comparative Example, or each Reference Example were allowed to stand for 24 hours in an environment with a temperature of 23 ° C. ± 2 ° C. and a humidity of 50% ± 5% after production. Then, from the center (core part) of the polyurethane molded body, 4 cm × 4 cm × 4 cm (density, hardness, and elastic modulus) or 2 cm × 3 cm × 4 cm (closed cell ratio) or 4 cm × 4 cm × 1.5 cm (water absorption). It was cut out to the size of rate) and used as an evaluation sample.

(Density of polyurethane molded product)
The density of the evaluation sample of the polyurethane molded product obtained in each Example, each Comparative Example, or each Reference Example was measured according to JIS K-7222. The unit was kg / m ³ .

(Hardness of polyurethane molded product)
The hardness (shore A) of the evaluation sample of the polyurethane molded product obtained in each example, each comparative example, or each reference example is measured by a rubber hardness tester (Polymer Meter Co., Ltd.) in accordance with JIS K-7312. Manufactured by, trade name: Ascar A type hardness tester).

(Closed cell ratio of polyurethane molded product)
For the evaluation sample of the polyurethane molded product obtained in each example, each comparative example, or each reference example, the closed cell ratio was measured by an air comparative hydrometer (manufactured by Toshiba Beckman Co., Ltd.) in accordance with ASTM D2856-70. , Product name: Model 930).

(Repulsive modulus of polyurethane molded product)
The elastic modulus of the evaluation of the polyurethane molded product obtained in each example, each comparative example, or each reference example was measured according to JIS K-6400.

(Water absorption of polyurethane molded product)
The evaluation sample of the polyurethane molded product obtained in each Example, each Comparative Example, or each Reference Example was dried at 50 ° C. for 24 hours, allowed to cool in a container containing a desiccant, and used for evaluation after drying. The weight of the sample was measured with a precision balance. Next, after the evaluation sample was completely immersed in distilled water for 24 hours at 20 ° C., the evaluation sample was taken out, the water on the surface thereof was wiped off, and the weight was measured by a precision balance. When the weight of the evaluation sample before immersion in distilled water was W0 and the weight after immersion in distilled water was W1, the water absorption rate was calculated based on the following formula.

Water absorption rate [%] = {(W1-W0) / W0} x 100
(Non-shrinkage of polyurethane molded product)
Deformation occurs when the polyurethane molded product shrinks. Therefore, with respect to the polyurethane molded products obtained in each Example, each Comparative Example, or each Reference Example, the presence or absence of deformation on the next day of their production was visually observed. The case where no deformation occurred was evaluated as "○", and the case where the deformation occurred was evaluated as "x".

(Raw material for polyurethane resin composition)
In each example, each comparative example, or each reference example, the polyurethane resin composition in each reference example has two types of (A-1) castor oil-based polyols shown in Table 1 as the (A) hydroxyl group-containing compound as a raw material. (A-2) polybutadiene polyol and three kinds of (A-3) amine polyols were appropriately selected and used in combination.

Further, in the polyurethane resin composition in each Example, each Comparative Example, or each Reference Example, one of the two types of compounds shown in Table 2 was used as the (B) isocyanate compound as a raw material. Further, as the catalyst (D) used for the reaction between the (A) hydroxyl group-containing compound and the (B) isocyanate compound, two types of catalysts shown in Table 2 were used in combination.

In each Example, Comparative Example, or Reference Example described later, the compositions of the respective components in the production of the polyurethane resin composition are summarized in Tables 3 to 5, but in these tables, (A). ) Specific types of hydroxyl group-containing compounds, (B) isocyanate compounds, and (D) catalysts are described by the abbreviations shown in Table 1 or Table 2.

(Example 1)
Examples include (A) hydroxyl group-containing compounds, (C) water, and (D) catalysts of the types (abbreviations) shown in Table 3, which are blended and mixed in the blending amounts shown in Table 3. A polyol mixture according to No. 1 was prepared. As shown in Table 3, this polyol mixture satisfies both mixing conditions 1 and 2. As described above, the storage stability of the prepared polyol mixture was evaluated and the viscosity was measured. The results are shown in Table 3.

Next, the (B) isocyanate compound of the type (abbreviation) shown in Table 3 is blended with the polyol mixture according to Example 1 in the blending amount shown in Table 3, and mixed for 7 seconds using a high-speed mixer having a rotation speed of 3000 rpm. did. As a result, a raw material mixture for producing the polyurethane resin composition according to Example 1 was prepared. The isocyanate index of this raw material mixture is 100 as shown in Table 3.

The prepared raw material mixture was poured into a 1 L open mold (molding mold), cured for a predetermined time, cured, and then demolded. As a result, a polyurethane molded product (polyurethane resin composition or polyurethane foam) according to Example 1 was obtained. As described above, various physical properties of the obtained polyurethane molded product were evaluated or measured. The results are shown in Table 3.

(Examples 2 to 7)
Polyols according to Examples 2 to 7 in the same manner as in Example 1 except that the types or amounts of (A) hydroxyl group-containing compound, (C) water, and (D) catalyst were changed as shown in Table 3. A mixture was prepared. As shown in Table 3, all of these polyol mixtures satisfy both the mixing conditions 1 and 2. As described above, the storage stability of these polyol mixtures was evaluated and the viscosity was measured. The results are shown in Table 3.

Further, the polyurethane resin compositions according to Examples 2 to 7 were prepared in the same manner as in Example 1 except that the type or blending amount of the (B) isocyanate compound was changed with respect to these polyol mixtures as shown in Table 3. A raw material mixture for production was prepared, and a polyurethane molded product according to Examples 2 to 7 was obtained. The isocyanate index of each of the prepared raw material mixtures is 100 as shown in Table 3. As described above, various physical properties of these polyurethane molded products were evaluated or measured. The results are shown in Table 3.

(Examples 8 to 13)
Polyols according to Examples 8 to 13 are the same as in Example 1 except that the types or amounts of (A) hydroxyl group-containing compound, (C) water, and (D) catalyst are changed as shown in Table 4. A mixture was prepared. As shown in Table 4, all of these polyol mixtures satisfy both the mixing conditions 1 and 2. As described above, the storage stability of these polyol mixtures was evaluated and the viscosity was measured. The results are shown in Table 4.

Further, the polyurethane resin compositions according to Examples 8 to 13 were prepared in the same manner as in Example 1 except that the type or amount of the (B) isocyanate compound was changed with respect to these polyol mixtures as shown in Table 4. While preparing, the polyurethane molded product according to Examples 8 to 13 was obtained. The isocyanate index of each of the prepared polyurethane resin compositions is 100 as shown in Table 4. As described above, various physical properties of these polyurethane molded products were evaluated or measured. The results are shown in Table 4.

(Comparative Examples 1 to 3)
As the (A) hydroxyl group-containing compound, one of (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol is not blended, and the type or amount of each component is blended. The polyol mixture according to Comparative Examples 1 to 3 was prepared in the same manner as in Example 1 except that the changes were made as shown in Table 5. As described above, the storage stability of these polyol mixtures was evaluated and the viscosity was measured. The results are shown in Table 5.

Further, the polyurethane resin composition according to Comparative Examples 1 to 3 was prepared in the same manner as in Example 1 except that the type or blending amount of the (B) isocyanate compound was changed with respect to these polyol mixtures as shown in Table 5. A raw material mixture for production was prepared, and a polyurethane molded product according to Comparative Examples 1 to 3 was obtained. The isocyanate index of each of the prepared raw material mixtures is 100 as shown in Table 5. As described above, various physical properties of these polyurethane molded products were evaluated or measured. The results are shown in Table 5.

(Reference Example 1, Comparative Example 4, and Reference Example 2 and 3)
A composition that does not meet the lower limit of the mixing condition 1 (Reference Example 1), a composition that exceeds the upper limit of the mixing condition 1 (Comparative Example 4), a composition that does not meet the lower limit of the mixing condition 2 (Reference Example 2), or an upper limit of the mixing condition 2. In Comparative Example 4 or Reference Examples 1 to 3 in the same manner as in Example 1 except that the type or blending amount of each component was changed as shown in Table 5 so as to have a composition exceeding (Reference Example 3). Such a polyol mixture was prepared. As described above, the storage stability of these polyol mixtures was evaluated and the viscosity was measured. The results are shown in Table 5.

Further, the polyurethane according to Comparative Example 4 or Reference Examples 1 to 3 is the same as in Example 1 except that the type or amount of the (B) isocyanate compound is changed with respect to these polyol mixtures as shown in Table 5. A raw material mixture for producing a resin composition was prepared, and a polyurethane molded product according to Comparative Example 4 or Reference Examples 1 to 3 was obtained. The isocyanate index of each of the prepared raw material mixtures is 100 as shown in Table 5. As described above, various physical properties of these polyurethane molded products were evaluated or measured. The results are shown in Table 5.

(Comparison of Examples, Comparative Examples and Reference Examples)
As shown in Examples 1 to 13, in the polyurethane resin composition according to the present disclosure, the previously prepared polyol mixture exhibits good storage stability (long-term stability), and its viscosity is within a range that is easy to handle. It has become. Further, in any of the polyurethane molded bodies according to the present disclosure (that is, the polyurethane resin composition according to the present disclosure), the water absorption rate is reduced to 20% or less, and good non-shrinkage can be realized. ..

Further, the polyurethane molded product according to the present disclosure not only has a good appearance, but also has a hardness (shore A) in the range of 15 to 60, and further, the use of water (C) which is a foaming agent. The density is relatively low compared to the amount. Further, in the polyurethane molded product according to the present disclosure, not only a good impact elastic modulus can be realized, but also the closed cell ratio is relatively high.

On the other hand, in Comparative Examples 1 to 3, the non-shrinkability of the obtained molded product is obtained unless the three essential compounds (A-1) to (A-3) are used as the (A) hydroxyl group-containing compound. , The water absorption rate is high, the appearance is bad, and the storage stability of the polyol mixture is insufficient. Further, if the upper limit of the mixing condition 1 is exceeded as in Comparative Example 4, the non-shrinkability of the obtained molded product is deteriorated and the appearance is also deteriorated.

Here, in Reference Example 1, the polyurethane resin composition deviates from the lower limit of the mixing condition 1, the closed cell ratio of the molded product is relatively low, and its appearance is deteriorated, but the water absorption rate is about the same as the conventional one. Can be realized and good non-shrinkability can be realized. In addition, good storage stability and viscosity can be achieved even in a polyol mixture. Further, in Reference Example 2 or 3, none of the mixing conditions 2 is satisfied, and the hardness of the molded product becomes too high or the storage stability of the polyol mixture is insufficient, but the water absorption rate of the molded product is high. It is as low as the examples, good non-shrinkage can be realized, and the closed cell ratio and appearance are also good.

Therefore, in the polyurethane resin composition according to the present disclosure, the three types (A-1) to (A-3) are used in combination as the (A) hydroxyl group-containing compound, and the mixing condition 1 is set to be equal to or lower than the upper limit. It can be seen that good low water permeability and non-shrinkage can be realized in the obtained molded product by blending (A-1) castor oil-based polyol and (A-2) polybutadiene polyol. Further, if the mixing condition 1 is satisfied, the closed cell ratio of the molded product is improved and a good appearance can be realized, and if the mixing condition 2 is further satisfied, the hardness of the molded product can be kept within a good range. It can be seen that the long-term stability of the polyol mixture can be improved.

It should be noted that the present invention is not limited to the description of the above-described embodiment, and various modifications can be made within the scope of the claims, and the present invention is disclosed in different embodiments and a plurality of modifications. Embodiments obtained by appropriately combining the above technical means are also included in the technical scope of the present invention.

INDUSTRIAL APPLICABILITY The present invention can be suitably used in the field of forming polyurethane foams that require low water permeability and good non-shrinkability, and in particular, for electrical and electronic components such as coating materials or sealing materials for electrical and electronic components. It can be widely and suitably used in the field.

Claims (7)

A polyurethane resin composition for electrical and electronic components obtained by reacting at least (A) a hydroxyl group-containing compound, (B) an isocyanate compound, and (C) water.
As the (A) hydroxyl group-containing compound, (A-1) castor oil-based polyol, (A-2) polybutadiene polyol, and (A-3) amine polyol are used, and
The mixing ratio ((A-1) / (A-2)) of the (A-1) castor oil-based polyol to the (A-2) polybutadiene polyol is 50 or less in terms of mass ratio.
Polyurethane resin composition. The mixing ratio ((A-1) / (A-2)) of the (A-1) castor oil-based polyol to the (A-2) polybutadiene polyol is 1 or more by mass ratio.
The polyurethane resin composition according to claim 1. Mixing ratio of the total amount of the (A-1) castor oil-based polyol and the (A-2) polybutadiene polyol to the (A-3) amine polyol ((A-1) + (A-2)) / ( A-3)) is characterized by having a mass ratio of 1 or more.
The polyurethane resin composition according to claim 1 or 2. Mixing ratio of the total amount of the (A-1) castor oil-based polyol and the (A-2) polybutadiene polyol to the (A-3) amine polyol ((A-1) + (A-2)) / ( A-3)) is characterized by having a mass ratio of 55 or less.
The polyurethane resin composition according to claim 3. The blending amount of the (C) water is 0.1 to 1.2% by mass when the total amount of the (A) hydroxyl group-containing compound, the (B) isocyanate compound, and the (C) water is 100% by mass. Characterized by being within the range of,
The polyurethane resin composition according to any one of claims 1 to 4. A molded product comprising the polyurethane resin composition according to any one of claims 1 to 5. An electrical and electronic component comprising a molded body made of the polyurethane resin composition according to any one of claims 1 to 5.