JP2003026758A - One component type solid urethane resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a one component type solid urethane resin composition capable of being easily handled and showing excellent humidity resistance, cooling and heating cycle resistance and the like each required for sealing an electronic part. SOLUTION: A one component type solid urethane resin composition contains (1) an isocyanate component composed of a blocked polyisocyanate and (2) a polyol component comprising a polyol which is solid at an ambient temperature and a diene-based polyol having no polyester bond, the ratio of the former to the latter being 1:1 to 4:1 by weight wherein the equivalent ratio of the hydroxy group to the isocyanate group is 0.8 to 1.2.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a one-component solid urethane resin composition.

[0002]

A urethane resin composition containing a blocked isocyanate obtained by reacting a polyisocyanate with a blocking agent as an isocyanate component can be made into a one-pack type composition and can be made water-based. It has been attracting attention in many fields because it can extend the life, reduce the heat generated during curing, and reduce the toxicity of isocyanate compounds.

However, the urethane resin composition which has been put into practical use as a urethane resin composition containing a blocked isocyanate is liable to lose surface smoothness when the thickness of the urethane resin layer is increased, and the hardness at the time of curing is high. It has a drawback that it is too much, and is mainly used only for limited applications such as a coating field.

Japanese Unexamined Patent Publication (Kokai) No. 7-25963 describes a vibration-damping molded product formed by using a one-component solid urethane resin composition containing a blocked isocyanate. Although this composition has the advantage of being easy to handle because it is a one-component type and solid, it is used as a vibration damping material, and is sufficiently used when it is used for sealing electronic electronic components and printed circuit boards. However, since it is not possible to impart sufficient moisture resistance, and it is not possible to sufficiently relieve the stress on the electronic and electrical components, the cycle resistance to cold and heat becomes poor. Furthermore, since it is necessary to cure at a high temperature of about 150 ° C., if it is used for the purpose of resin sealing of electronic electrical components and printed circuit boards, for example, the electronic components will be adversely affected, and the sealing of electronic electrical components and printed circuit boards will be great. It cannot be used as a potting agent or potting agent.

Attempts have been made to improve the thermal cycle resistance by adding a plasticizer to the urethane resin composition to impart flexibility to the cured product. However, when a plasticizer is added, a solid resin composition is obtained. However, there is a drawback that the moisture resistance of the cured product is likely to deteriorate.

[0006]

The main object of the present invention is to:
A one-component solid urethane resin composition that is easy to handle, and has a moisture resistance required for sealing electronic electronic components,
It is an object of the present invention to provide a urethane resin composition having excellent resistance to cold and heat cycles.

[0007]

Means for Solving the Problems As a result of intensive studies to achieve the above-mentioned object, the present inventor has used a blocked polyisocyanate as an isocyanate component and has a polyol and an ester bond which are solid at room temperature as a polyol component. When a diene-based polyol not containing is used together in a specific ratio, a one-pack type solid polyol which is solid at room temperature and has excellent storage stability can be obtained, and the cured product formed is moisture resistant. It has been found that it has excellent resistance to cold and heat cycles. Furthermore, when a blocked isocyanate obtained by blocking an aromatic polyisocyanate with a specific blocking agent is used as the isocyanate component, a urethane resin composition having excellent low-temperature curability is obtained, which is used for electronic components and printed circuit boards. It has been found that it is possible to prevent adverse effects on parts even when used for sealing, and the present invention has been completed here.

That is, the present invention provides the following one-component solid polyurethane composition. 1. (I) an isocyanate component composed of a blocked polyisocyanate, and (ii) a polyol component containing a solid polyol at room temperature and a diene polyol not containing an ester bond in a weight ratio of the former: the latter = 1: 1 to 4: 1. The equivalent ratio of hydroxyl group / isocyanate group is 0.8-1.
A one-pack type solid urethane resin composition, which is contained in a ratio of 2. 2. Item 1 above, wherein the blocked polyisocyanate is obtained by reacting at least one blocking agent selected from the group consisting of phenols, oximes, β-diketones and β-diesters with an aromatic polyisocyanate. The one-component solid urethane resin composition described in 1. 3. Diene-based polyol containing no ester bond
Item 3. The one-pack type according to Item 1 or 2, which is at least one component selected from terminal hydroxyl group-containing polybutadiene, terminal hydroxyl group-containing polyisoprene, terminal hydroxyl group-containing hydrogenated polybutadiene, and terminal hydroxyl group-containing hydrogenated polyisoprene. Solid urethane resin composition.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Each component to be added to the one-pack type solid polyisocyanate resin composition of the present invention will be described below. Isocyanate Component In the polyurethane resin composition of the present invention, it is necessary to use a blocked polyisocyanate as an isocyanate component. By using the blocked polyisocyanate, when a one-pack composition is prepared, a curing reaction does not occur at room temperature, and a composition having excellent storage stability can be obtained.

The blocked polyisocyanate used in the present invention is obtained by reacting a polyisocyanate compound with a blocking agent.

As the polyisocyanate compound, various known polyisocyanate compounds having two or more isocyanate groups per molecule can be used. For example, 2,4 tolylene diisocyanate, 2,6 tolylene diisocyanate, 4,4 Aromatic polyisocyanates such as diphenylmethane diisocyanate, 2,4 diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, ethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, cyclohexane 1,4-diisocyanate, 1- Methyl-cyclohexane-2,4-diisocyanate, isophorone diisocyanate, 1,4
-Xylene diisocyanate, norbornane diisocyanate, buretted isocyanate, nurated isocyanate and the like can be used.

The polyisocyanate compound preferably has an average of about 2 to 100 isocyanate groups per molecule, and more preferably an average of about 2.5 to 10 isocyanate groups. If the number of isocyanate groups is too small, the cured product does not have sufficient water resistance, and if the number of isocyanate groups is too large, the viscosity at the time of melting becomes high, and the hardness of the cured product is high. However, there is an adverse effect such that the temperature becomes higher and the resistance to thermal cycle resistance deteriorates. Further, the polyisocyanate compound preferably has a number average molecular weight of about 100 to 3000 per one isocyanate group, more preferably about 100 to 600. If the molecular weight per one isocyanate group is too large, the weight ratio of the isocyanate compound in the case of the polyurethane composition increases, and the viscosity at the time of melting increases. Further, the weight ratio of the solid polyol becomes relatively small, and it becomes difficult to obtain a solid polyurethane resin composition at room temperature, and the weight ratio of the diene-based polyol becomes small, and the hardness of the cured product becomes too high. There are also harmful effects.

As the blocking agent, phenol, cresol, xylenol, p-nonylphenol, p-cumylphenol, p-methoxyphenol, 3-methyl-
Phenols such as 6-t-butylphenol, 4-methyl-2-t-butylphenol, p-tert-octylphenol, metacresol and alkylphenol;
Malonate, diallyl malonate, methyl acetoacetate, ethyl acetoacetate, acetoacetate, 2,4-
Β-diketones such as pentanedione; diethyl malonate, diethyl methylpropanoate, γ-butyrolactam,
β-diesters such as ε-caprolactane, ethyl dicyclohexanecarboxylate, and diethylmalonate; oximes such as acetoxime, cyclohexanooxime, methylisobutylketoxime, benzophenone oxime, methylethylketone oxime, cyclohexanone oxime; methanol, ethanol, propanol, isopropanol , Butanol, 2-ethylhexanol, cyclohexanol, benzyl alcohol, diacetone alcohol, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monobutyl ether, pentaethylene glycol monobutyl ether, ethylene glycol monohexyl ether , Diethylene glycol Recall monohexyl ether,
Ethylene glycol mono-2-ethylenehexyl ether, diethylene glycol mono-2-ethylhexyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, allyl alcohol, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, hydroxyethyl methacrylic acid, etc. Alcohols and the like can be mentioned.

The blocked polyisocyanate can be obtained by a known method. For example, if necessary, an active hydrogen-free solvent such as ether, ketone, aliphatic hydrocarbon, and aromatic hydrocarbon is used, and the above polyisocyanate compound and the blocking agent are treated at, for example, 70 to 90 ° C.
The blocked polyisocyanate can be obtained by reacting at a moderate temperature. The ratio of the blocking agent to the polyisocyanate compound may be usually in the range of the former: the latter = 1: 0.8 to 1: 1.2 in an equivalent ratio.

Among the above-mentioned blocked polyisocyanates, in particular, an aromatic polyisocyanate is reacted with at least one blocking agent selected from the group consisting of phenols, oximes, β-diketones and β-diesters. The blocked polyisocyanate thus obtained has a low dissociation temperature of the blocking agent, and when this is used as an isocyanate component, the curing reaction of polyurethane occurs at a relatively low temperature. When used for stopping, it is advantageous in that the electronic parts can be prevented from being exposed to high temperatures. Polyol Component In the present invention, it is necessary to use, as the polyol component, a solid polyol at room temperature and a diene-based polyol containing no ester bond in combination. (I) Solid Polyol A polyol that is solid at room temperature is a component necessary to form a urethane resin composition that is solid at room temperature, and usually has a melting point of 4
What has a temperature of about 0 ° C. or higher may be used. The specific melting point may be appropriately selected according to the purpose of use, for example,
When used for resin encapsulation of electronic parts and printed circuit boards, it is preferable to cause a curing reaction at a relatively low temperature of about 120 ° C. or less. It is preferable to use a resin composition that allows the object to be treated to be dipped. From this point of view, the solid polyol preferably has a melting point of about 40 to 120 ° C, more preferably about 50 to 90 ° C.

The solid polyol preferably has an average of 2 to 20 hydroxyl groups per molecule, and more preferably an average of 2.5 to 6 hydroxyl groups. If the number of hydroxyl groups is too small, the cured product does not have sufficient water resistance, and if the number of hydroxyl groups is too large, the melting point becomes too high or the hardness of the cured product becomes too high. Therefore, there is an adverse effect such as poor resistance to cold and heat cycles. The solid polyol preferably has a number average molecular weight per hydroxyl group of about 50 to 2000,
It is more preferably about 100 to 1000. When the molecular weight per hydroxyl group is too large, the weight ratio of the solid polyol in the case of the urethane resin composition is increased, and the weight ratio of the diene-based polyol is relatively decreased.
As a result, the effects of improving the humidity resistance, the resistance to cold and heat cycles, etc. tend to be insufficient. On the other hand, if the molecular weight per hydroxyl group is too small, there is a problem such that the viscosity during melting tends to increase.

The solid polyol may be appropriately selected and used from known polyols which are solid at room temperature in consideration of the above-mentioned conditions, and examples thereof include alkylene polyols, polyoxyalkylene polyols, polyalkyl ester polyols and aromatic series polyols. A polyol or the like can be used.

In the present invention, for example, an ester of 12-hydroxystearic acid and glycerin obtained by hydrogenating castor oil can be preferably used. this is,
By appropriately setting the hydrogenation amount, it is possible to set the melting point in an appropriate range. (Ii) Diene-based polyol In the urethane resin composition of the present invention, by blending a diene-based polyol containing no ester bond, excellent moisture resistance can be imparted to a urethane cured product, and further, the hardness of the cured product, particularly, The low-temperature hardness becomes low, and it has excellent cold-heat cycle resistance.

As the diene-based polyol containing no ester bond, the average number of hydroxyl groups per molecule is 2 or more,
An average of about 2 to 100 pieces, and more preferably an average of about 2 to 6 pieces can be used. If the number of hydroxyl groups is too small, the cured product does not have sufficient water resistance, and if the number of hydroxyl groups is too large, the viscosity at the time of melting increases and the hardness of the cured product increases. However, there is an adverse effect such that it tends to be inferior in cold-heat cycle resistance due to too much.

The diene-based polyol preferably has a number average molecular weight of about 200 to 5,000 per hydroxyl group, more preferably about 500 to 3,000. If the molecular weight per hydroxyl group is too large, sufficient water resistance cannot be imparted to the cured product. On the other hand, if the molecular weight per hydroxyl group is too small, the weight ratio of the diene-based polyol decreases. However, there is an adverse effect that the hardness of the cured product cannot be reduced sufficiently and the resistance to cold-heat cycle becomes poor.

The type of diene-based polyol having no ester bond is not particularly limited, and examples thereof include terminal hydroxyl group-containing polybutadiene, terminal hydroxyl group-containing polyisoprene, terminal hydroxyl group-containing hydrogenated butadiene, terminal hydroxyl group-containing hydrogenated product. Polyisoprene, a mixture of two or more of these and the like can be used. Among these, hydrogenated products such as hydrogenated butadiene containing terminal hydroxyl groups and hydrogenated polyisoprene containing terminal hydroxyl groups may be those obtained by partially or entirely hydrogenating the polymer.

In the present invention, it is preferable to use a liquid diene-based polyol among the above-mentioned diene-based polyols, and it is particularly preferable to use a terminal hydroxyl group-containing polybutadiene. Urethane Resin Composition The urethane resin composition of the present invention contains an isocyanate component composed of the blocked polyisocyanate described above and a polyol component composed of a solid polyol and a diene-based polyol having no ester bond.

The mixing ratio of the isocyanate component and the polyol component is not particularly limited, but usually, the equivalent ratio of hydroxyl group / isocyanate group is about 0.8 to 1.2, preferably about 0.9 to 1.1. The range should be

The ratio of the solid polyol to the diene-based polyol in the polyol component is a weight ratio of solid polyol: diene-based polyol = 1: 1 to 4: 1. By using the solid polyol and the diene-based polyol together in such a ratio, it is possible to obtain a urethane resin composition which is solid at room temperature and which has excellent moisture resistance of the cured product and excellent heat and cold cycle resistance.

The urethane resin composition of the present invention further comprises
If necessary, it is possible to add a curing catalyst,
The curing temperature can be lowered by incorporating the curing catalyst. As the curing catalyst, known ones can be used, and examples thereof include inorganic or organic metal compounds; potassium salts such as alkylsulfuric acid and alkylsulfonic acid, sodium salts; sodium, potassium and titanium fatty acids having about 8 to 20 carbon atoms, Metal salts of nickel, cobalt, cadmium, barium, calcium, zinc, etc .; dibutyltin laurate, dioctyltin maleate, dibutyltin oxide, bis (2-ethylhexyl) tin oxide,
Organotin compounds such as 1,1,3,3-tetrabutyl-1,3-diacetoxydistannoxane, tin octylate, and dibutyltin acetate; triethylamine, tributylamine, 2-dimethylaminoethanol, triethanolamine, dodecyldimethylamine , N, N-dimethylcyclohexylamine, N-methylmorpholine or 1,4-diazabicyclo- [2,2,2] -octane,
Tertiary amines such as 1,8-diazabicyclo [5.4.0] -7-undecene and salts thereof can be used.

The amount of the curing catalyst used cannot be unconditionally specified because it depends on the types of the isocyanate component and the polyol component, the type of the catalyst, etc., but the amount of the curing catalyst used in the resin composition is usually about 5% by weight or less. It may be determined as appropriate.

The blocked polyisocyanate obtained by reacting the above-mentioned aromatic polyisocyanate with at least one blocking agent selected from the group consisting of phenols, oximes, β diketones and β diesters has a dissociation temperature. Is a relatively low isocyanate component,
By using this as an isocyanate component, and further by adding the above-mentioned catalyst as required, a urethane resin composition which is cured at a relatively low temperature of about 120 ° C. or less can be obtained. Such a low-temperature curable urethane resin composition is particularly suitable for resin encapsulation of electronic electrical components and printed circuit boards because it can prevent electronic components from being excessively heated during curing.

The urethane resin composition of the present invention further comprises
If necessary, short-chain diols; chain extenders such as trimethylolpropane; hydrated alumina, talc, clay, calcium carbonate, baryta powder, silica powder, alumina, carbon black, titanium oxide, iron oxide, and other fillers. To pigments; flame retardants such as phosphorus compounds, halogen compounds, antimony oxides; antioxidants; UV inhibitors; moisture adsorbents; defoamers; fungicides; crosslinkers; silane-based, titanium-based, amine-based, etc. Various additives such as coupling agents can be blended. The amount of these additives to be added may be appropriately selected from the range of the usual amounts added, depending on the purpose.

As a method for producing the one-pack type solid urethane resin composition of the present invention, for example, after the blocked polyisocyanate is produced by the above-mentioned method, solid polyol is added to After melting at temperature, the pressure is gradually reduced to distill off the volatile components, and then a diene polyol not containing an ester bond is added and kneaded, and then additives such as a catalyst are added to make the mixture uniform. Although a method of mixing can be mentioned, the method is not limited to this, and any method can be adopted as long as it is a method capable of mixing each component to form a uniform solid composition.

The urethane resin composition of the present invention is usually used as a liquid by heating it to a temperature above these temperatures depending on the dissociation temperature of the compounded blocked polyisocyanate compound and the melting point of the solid polyol. For example, when used for sealing electronic electronic components and printed circuit boards, the urethane resin composition is in a molten state, and after immersing the object to be treated therein, at a temperature above the dissociation temperature of the blocked isocyanate, for example, It may be cured for about 0.5 to 2 hours.

[0031]

The one-pack type solid urethane resin composition of the present invention is a composition which is easy to handle and is solid at room temperature, and the cured product is excellent in various properties such as moisture resistance and cold / heat cycle resistance. Becomes

Further, by selecting a compound that dissociates at a low temperature as the blocked polyisocyanate and a component having a relatively low melting point as the solid polyol, it becomes possible to melt and cure at a lower temperature than in the past, and to obtain an electron It is suitable for sealing electrical components and printed circuit boards.

[0033]

EXAMPLES The present invention will be described in more detail with reference to examples.

Examples 1 to 4 and Comparative Example 1 A flask equipped with a stirrer, a thermometer and a cooling tube was charged with the polyisocyanate and the blocking agent in the amounts shown in Table 1 below, and the total amount of the polyisocyanate and the blocking agent was added. 100
Methyl ethyl ketone was added at a ratio of 30 parts by weight with respect to parts by weight, the temperature was raised to 80 to 90 ° C while paying attention to heat generation, and dibutyltin dilaurate as a silver-based catalyst was added at 500 pp with respect to the total amount of polyisocyanate and blocking agent.
m was added and reacted for 30 hours to obtain a blocked polyisocyanate.

Next, the solid polyol shown in Table 1 below and the blocked polyisocyanate 10 were placed in this flask.
Methyl ethyl ketone was added in an amount of 10 parts by weight to 0 parts by weight, and the mixture was sufficiently stirred, and the volatile components were distilled off over a period of about 30 minutes at a final temperature of 90 to 95 ° C. and a pressure of 50 mmHg while reducing the pressure with a vacuum pump. .

The diene-based polyol containing no ester bond shown in Table 1 below was added thereto, and the amount of dibutyltin dilaurate was 6000 ppm based on the total amount of the blocked polyisocyanate, the solid polyol and the diene-based polyol. Was added and mixed by stirring for 5 to 20 minutes to obtain a one-component solid urethane resin composition.

Regarding each urethane resin composition obtained,
Various characteristics were determined by the following methods. The results are also shown in Table 1. [Evaluation Method] * At room temperature, 20 g of the resin composition was placed in a 10 cm diameter dish (made by tin plate), placed on a hot plate at 100 ° C. for about 5 minutes to melt, and then left at room temperature for a whole day and night, and touched. The condition was examined with a finger.

When there is no tack, the condition at room temperature is good, and it is indicated by ◯, and when it is difficult to maintain the shape because of tack, it is indicated by ×, which indicates that the condition at room temperature is poor. * 80 ° C viscosity Using a hot water circulation type viscometer, confirm that the temperature has reached 80 ° C, put about 1 g of the sample into a predetermined metal container, and confirm that it has melted. The rotation speed was selected and the viscosity was determined. * Curable: 50 g of the resin composition was placed in a 10 cm diameter kettle dish (made by tinplate) and heated for 2 hours in a blast dryer at 100 ° C., and the resulting cured product was cut into 2 cm squares and 100 ml.
It was placed in ion-exchanged water, and the number of days until the shape could not be retained was examined by applying external pressure under heating and reflux.

The case where the number of days is 7 days or more is represented by O, the case of 4 to 7 days is represented by Δ, and the case of 4 days or less is represented by X. * Hardness of cured product A JISA hardness of the cured product obtained by the same method as in the above-mentioned curability test was measured at 23 ° C and -20 ° C. When the hardness was A90 or less, it was evaluated as “good” because it was flexible.

[0040]

[Table 1] In addition, each symbol shown in Table 1 shows the following components. MR-200: Polymethylene polyphenylene polyisocyanate (Mn = 380, about 2.7 functional, Nippon Polyurethane Industry, trade name Millionate MR-200) MR-400: Polymethylene polyphenylene polyisocyanate (Mn = 400, about 2.9). Functionality, manufactured by Nippon Polyurethane Industry, trade name Millionate MR-400) PTBP: p-tert-butylphenol (manufactured by Dainippon Ink and Chemicals, trade name PTBP) PCWAX: 12 ester of hydroxystearic acid and glycerin (melting point: 80 ° C., hydroxyl group Value 150, Mn = 3
80, 2.7 functional (manufactured by braswey, Hydrogenated CASTOR) Castor wax: ester of 12 hydroxystearic acid and glycerin (melting point: 75 ° C, hydroxyl value 150, M
n = 350, 2.7 functional (made by Ito Oil Co., Ltd.) PolyBD1000: polybutadiene (Mn = 120)
0, hydroxyl value 105, number of functional groups 2.3) (manufactured by Idemitsu Petrochemical, trade name polybutadiene R15HT) PolyBD2000: polybutadiene (Mn = 280)
0, hydroxyl value 47, functional group 2.3) (made by Idemitsu Petrochemical, trade name polybutadiene R45HT) POLYCASTOR: ricinoleate type polyester polyol (Mn = 430, hydroxyl value 159, functional group 2.7, made by Ito Oil, POLYCASTOR # 10) Further, with respect to the urethane resin composition obtained in Example 1, 50 g of the urethane resin composition was sampled in a ket tray having a diameter of 10 cm (manufactured by tin plate), cured under each condition shown in Table 2, and then the JISA hardness was measured.

The cured product was cut into a piece of about 1.5 mm square, and about 1.5 g was precisely weighed, and tetrahydrofuran 1
It was put in 00 g and stirred for 1 hour using a magnetic stirrer. Then, after filtering with a filter paper which was precisely weighed in advance, the whole filter paper was dried under reduced pressure at 100 ° C. for 1 hour. After drying, the product was placed in a desiccator, allowed to stand, weighed, the weight reduction rate was calculated, and the residue was taken as the gel fraction.

The above results are shown in Table 2 below.

[0043]

[Table 2]

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshimichi Takei             3-5-1 Doucho, Takatsuki City, Osaka Prefecture             Click Co., Ltd. (72) Inventor Akihiko Bessho             3-5-1 Doucho, Takatsuki City, Osaka Prefecture             Click Co., Ltd. (72) Inventor Kiyoo Kataoka             2-6-12 Minamihonmachi, Chuo-ku, Osaka-shi, Osaka Prefecture             Marmalion Osaka Building Kyoeisha Chemical Co., Ltd.             Within (72) Inventor Naomi Takenaka             5-2-5 Nishikujo-cho, Nara City, Nara Prefecture Kyoeisha             Nara Institute of Chemistry Co., Ltd. F-term (reference) 4J034 AA04 BA03 BA07 DA01 DB03                       DB07 DC50 DF01 DF16 DF20                       DG02 DQ09 HA01 HA06 HA07                       HB08 HC03 HC12 HC17 HC22                       HC46 HC52 HC54 HC61 HC63                       HC64 HC67 HC71 HC73 HD03                       HD05 HD12 HD15 QA03 RA08                       RA11

Claims (3)

[Claims] 1. A weight ratio of (i) an isocyanate component comprising a blocked polyisocyanate, and (ii) a polyol which is solid at room temperature and a diene-based polyol containing no ester bond, the former: the latter = 1: 1 to 4: 1. The polyol component contained in 1 is used in a hydroxyl group / isocyanate group equivalent ratio of 0.8.
A one-component solid urethane resin composition, characterized in that it is contained at a ratio of 1.2. 2. A blocked polyisocyanate obtained by reacting at least one blocking agent selected from the group consisting of phenols, oximes, β-diketones and β-diesters with an aromatic polyisocyanate. The one-component solid urethane resin composition according to claim 1. 3. A diene-based polyol having no ester bond is at least one selected from terminal hydroxyl group-containing polybutadiene, terminal hydroxyl group-containing polyisoprene, terminal hydroxyl group-containing hydrogenated polybutadiene and terminal hydroxyl group-containing hydrogenated polyisoprene. The one-component solid urethane resin composition according to claim 1 or 2, which is a component of