Two-part curable urethane resin composition, method for producing urethane cured resin, and applications thereof

Abstract

To provide a highly safe two-part curable urethane resin composition with reduced burden on the user and the environment, ensuring reduced malodor, a method for producing a urethane cured resin, and applications of the two-part curable urethane resin composition.SOLUTION: A two-part curable urethane resin composition comprises a base agent (A) containing a polyol and a curing agent (B) containing an isocyanate compound. The base agent (A) comprises at least one terpene-based hydrocarbon selected from the group consisting of d-limonene, l-limonene, α-pinene, β-pinene, γ-terpinene, β-caryophyllene, 3-carene, myrcene, elemene, and ocimene. The curing agent (B) comprises at least one acetoacetic ester represented by the general formula (where R is a C 1-4 linear / branched alkyl group, an allyl group, a 2-methoxyethyl group or a benzyl group).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a two-component curing type urethane resin composition containing a base agent and a curing agent, a method for producing a cured urethane resin product, and uses of the two-component curing type urethane resin composition. [Background technology]

[0002] Conventionally, two-component curing urethane resins have been widely used in applications such as paints, adhesives, and casting. Petroleum-based hydrocarbons are used as solvents for two-component curing urethane resins, and xylene is particularly commonly used (see, for example,

[0034] of Patent Document 1). This is because xylene has excellent solubility and is low cost.

[0003] However, xylene is designated as a non-medicinal hazardous substance under the Poisonous and Deleterious Substances Control Law and as a Class 2 organic solvent under the Ordinance for Prevention of Organic Solvent Poisoning, and must be handled with care due to its toxicity. Xylene is particularly irritating to the eyes and airways, and exposure to high concentrations is known to cause headaches, fatigue, temporary elation, coma, nausea, gastrointestinal disorders, loss of consciousness, lung disorders, liver disorders, kidney disorders, brain disorders, nerve disorders, and death. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-222773 A Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a two-component curing urethane resin composition which has an improved odor and is highly safe, which places a low burden on users and the environment, a method for producing a cured urethane resin product, and uses of the two-component curing urethane resin composition. [Means for solving the problem]

[0006] The two-component curing urethane resin composition of the present invention contains a base agent (A) containing a polyol and a curing agent (B) containing an isocyanate compound. The base agent (A) contains at least one terpene-based hydrocarbon selected from the group consisting of d-limonene, l-limonene, α-pinene, β-pinene, γ-terpinene, β-caryophyllene, 3-carene, myrcene, elemene, and ocimene. The curing agent (B) is a compound represented by the general formula: [ka] (In the formula, R represents a linear or branched alkyl group having 1 to 4 carbon atoms, an allyl group, a 2-methoxyethyl group, or a benzyl group.) The acetoacetate composition contains at least one acetoacetate represented by the formula:

[0007] The method for producing a cured urethane resin product of the present invention is a method for producing a cured urethane resin product using a two-component curing type urethane resin composition including a base agent (A) containing a polyol and a curing agent (B) containing an isocyanate compound, A step of adding at least one terpene hydrocarbon selected from the group consisting of d-limonene, l-limonene, α-pinene, β-pinene, γ-terpinene, β-caryophyllene, 3-carene, myrcene, elemene, and ocimene to the main agent (A); adding at least one acetoacetic ester represented by the above general formula to the curing agent (B); and mixing the base agent (A) to which the terpene hydrocarbons have been added and the curing agent (B) to which the acetoacetic esters have been added, and curing the mixture.

[0008] The present invention provides a coating material, an adhesive, or a casting resin composition containing the above two-component curing type urethane resin composition. Effect of the Invention

[0009] According to the present invention, by incorporating specific terpene hydrocarbons and acetoacetic esters in the base agent (A) and the curing agent (B), respectively, it is possible to obtain a urethane resin cured product that is less susceptible to bleeding and has good hardness. The above-mentioned terpene hydrocarbons and acetoacetate esters are highly safe and do not have an irritating odor like xylene, and therefore improve the working environment and reduce the burden on users and the environment. In addition, the terpene hydrocarbons and acetoacetic esters reduce the viscosity of the base agent (A) and the hardener (B), respectively, and can also suppress an increase in viscosity after the base agent (A) and the hardener (B) are mixed, so that workability such as casting is not impaired. [Brief description of the drawings]

[0010] [Figure 1A] 1 is a photograph showing the results of a bleeding confirmation test carried out on the cured products of a control and samples Nos. 1 to 5 in the examples of the present invention. [Figure 1B] 4 is a photograph showing the results of a bleeding confirmation test carried out on the cured products of Samples Nos. 6 to 10 in the examples of the present invention. [Figure 1C] 4 is a photograph showing the results of a bleeding confirmation test carried out on the cured products of Samples Nos. 11 to 13, which are comparative examples of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The two-component curing type urethane resin composition of the present invention will be described below. The two-component curing type urethane resin composition of the present invention contains a main agent (A) and a curing agent (B).

[0012] The base material (A) contains a polyol. Examples of the polyol include low molecular weight polyols having a number average molecular weight of less than 500 and high molecular weight polyols having a number average molecular weight of 500 or more. Examples of low molecular weight polyols include low molecular weight polyhydric alcohols such as ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, diethylene glycol, and diglycerin; low molecular weight sugar-based polyhydric alcohols such as sorbitol, sucrose, glucose, lactose, and sorbitan; and low molecular weight polyoxyalkylene polyols obtained by reacting at least one of these with alkylene oxide. Suitable examples of the polymer polyol include one or more selected from the group consisting of polyoxyalkylene polyols, polyester polyols and hydrocarbon polyols, and have a number average molecular weight of 500 or more, preferably 1,000 or more. These can be used alone or in combination of two or more.

[0013] Examples of polyoxyalkylene polyols include those obtained by ring-opening addition polymerization of alkylene oxides and those obtained by ring-opening addition polymerization of alkylene oxides to an initiator such as a compound containing two or more active hydrogens. Specifically, examples of polyoxyalkylene polyols include polyoxyethylene polyols, polyoxypropylene polyols, polyoxybutylene polyols, polytetramethylene ether polyols, poly(oxyethylene)-poly(oxypropylene)-random or block copolymer polyols, poly(oxypropylene)-poly(oxybutylene)-random or block copolymer polyols, and other polyether polyols, and also include those in which these various polyether polyols are reacted with organic isocyanates in excess of hydroxyl groups relative to isocyanate groups to give hydroxyl groups at the molecular ends. These can be used alone or in combination of two or more. From the viewpoint of workability, the polyoxyalkylene polyol preferably has a number average molecular weight of 500 to 100,000, more preferably 1,000 to 30,000, and particularly preferably 1,000 to 20,000. The average number of alcoholic hydroxyl groups per molecule is 2 or more, more preferably 2 to 4, and most preferably 2 to 3. In addition, polyoxyalkylene polyol means that, for example, 50% by mass or more, preferably 80% by mass or more, of the portion excluding hydroxyl groups in 1 mole of the molecule is composed of polyoxyalkylene, and the remaining portion may be modified with urethane, ester, polycarbonate, polyamide, polyacrylate, polyolefin, etc.

[0014] Examples of polyester polyols include polyester polyols, polyesteramide polyols, polyether-polyester polyols, polycarbonate polyols, and poly(meth)acrylic polyols. Examples of polyester polyols and polyesteramide polyols include compounds obtained by dehydration condensation reaction between known dicarboxylic acids such as succinic acid, adipic acid, and terephthalic acid, their acid esters, acid anhydrides, and compounds such as polyols and polyamines containing two or more active hydrogen groups. Other examples include lactone-based polyester polyols obtained by ring-opening polymerization of cyclic ester (i.e., lactone) monomers such as ε-caprolactone, drying oils, and various modified products of drying oils. Examples of drying oils and various modified products thereof include castor oil-based polyols. Examples of the polyether / polyester polyol include compounds produced from the above-mentioned polyoxyalkylene polyol and the above-mentioned dicarboxylic acid, acid anhydride, and the like. Examples of poly(meth)acrylic polyols include those obtained by copolymerizing hydroxyethyl (meth)acrylate containing a hydroxyl group with other (meth)acrylic acid alkyl ester monomers. These can be used alone or in combination of two or more.

[0015] Examples of the hydrocarbon polyol include polybutadiene polyols such as polybutadiene polyols and hydrogenated polybutadiene polyols, polyisoprene polyols, hydrogenated polyisoprene polyols, chlorinated polyethylene polyols, chlorinated polypropylene polyols, etc. These may be used alone or in combination of two or more.

[0016] The curing agent (B) contains an isocyanate compound. Examples of the isocyanate compound include polyisocyanate compounds containing two or more isocyanate groups in the molecule. Examples of the polyisocyanate compound include toluene diisocyanates such as 2,4-toluene diisocyanate and 2,6-toluene diisocyanate, diphenylmethane diisocyanates (MDI) such as 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate and 2,2'-diphenylmethane diisocyanate, 1,2-phenylene diisocyanate, 1,3-phenylene diisocyanate, 1,4- Phenylene diisocyanates such as phenylene diisocyanate, 2,4,6-trimethylphenyl-1,3-diisocyanate, 2,4,6-triisopropylphenyl-1,3-diisocyanate, 1,4-naphthalene diisocyanate, 1,5-naphthalene diisocyanate and other naphthalene diisocyanates, chlorophenylene-2,4-diisocyanate, 4,4'-diphenyl ether diisocyanate, 3,3'-dimethyldiphenyl Aromatic diisocyanates such as 3,3'-dimethoxydiphenyl-4,4'-diisocyanate, 1,6-hexamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, decamethylene diisocyanate, and lysine diisocyanate. Examples of the diisocyanate include aromatic aliphatic diisocyanates such as xylylene diisocyanates such as o-xylylene diisocyanate, m-xylylene diisocyanate, and p-xylylene diisocyanate, and alicyclic diisocyanates such as 1,4-cyclohexyl diisocyanate, isophorone diisocyanate, hydrogenated toluene diisocyanate, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Examples of the diisocyanate include polymethylene polyphenyl polyisocyanate and crude toluene diisocyanate. These can be used alone or in combination of two or more.

[0017] The ratio of the main agent (A) to the curing agent (B) can be determined by the ratio of the polyol and the isocyanate compound contained in each. Specifically, it is preferable to mix the main agent (A) and the curing agent (B) so that the equivalent ratio of the hydroxyl group of the polyol to the isocyanate group of the isocyanate compound is NCO / OH=1.0 to 1.5.

[0018] One or both of the base agent (A) and the curing agent (B) may contain additives such as conventionally used plasticizers, fillers, weather stabilizers, adhesion promoters, storage stability improvers, curing accelerators, colorants, etc. These additives can be arbitrarily blended in appropriate combinations depending on the purpose and application of the resin composition of the present invention. The curing accelerator may be, for example, an organic tin compound such as dibutyltin dilaurate, etc. The curing accelerator is preferably added to the main component (A) in advance.

[0019] The main agent (A) contains terpene hydrocarbons selected from the group consisting of d-limonene, l-limonene, α-pinene, β-pinene, γ-terpinene, β-caryophyllene, 3-carene, myrcene, elemene, and ocimene. These terpene hydrocarbons have excellent affinity, solubility, or dispersibility with respect to the polyol contained in the main agent (A), and can suppress the occurrence of turbidity and phase separation, and can also suppress the occurrence of so-called bleeding, in which terpene hydrocarbons and the like bleed out onto the surface of the cured product. In addition, the addition of terpene hydrocarbons can reduce the viscosity of the main agent (A), which can contribute to improving workability. Furthermore, the terpene hydrocarbons have no or very low irritating odors and are highly safe. The terpene hydrocarbons can be used alone or in combination of two or more. This allows the main component (A) to emit a desired scent, which is expected to improve the working environment.

[0020] The content of the terpene hydrocarbons is preferably 35% by mass or less, preferably 30% by mass or less, based on the total amount of the main agent (A) containing the terpene hydrocarbons. The content of the terpene hydrocarbons is preferably 5% by mass or more, preferably 10% by mass or more, based on the total amount of the main agent (A) containing the terpene hydrocarbons. This can improve the working environment and workability, and can provide a cured product with a desired hardness without bleeding.

[0021] The curing agent (B) has the general formula: [ka] (In the formula, R represents a linear or branched alkyl group having 1 to 4 carbon atoms, an allyl group, a 2-methoxyethyl group, or a benzyl group.) The compound contains acetoacetic esters represented by the formula:

[0022] Specifically, examples of acetoacetate esters represented by the above general formula include methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, isopropyl acetoacetate, butyl acetoacetate, isobutyl acetoacetate, tert-butyl acetoacetate, allyl acetoacetate, 2-methoxyethyl acetoacetate, and benzyl acetoacetate.

[0023] These acetoacetic esters have excellent affinity or solubility or dispersibility for the isocyanate compound contained in the curing agent (B), and can suppress the occurrence of turbidity and phase separation, and can also suppress the occurrence of so-called bleeding, in which the acetoacetic esters or the like seep out onto the surface of the cured product. In addition, the addition of acetoacetic esters can reduce the viscosity of the curing agent (B), which can contribute to improving workability. Furthermore, the acetoacetic esters have no or a significantly low irritating odor and are highly safe. Acetoacetic esters can be used alone or in combination of two or more kinds. This allows the curing agent (B) to emit a desired scent, which is expected to improve the working environment.

[0024] The content of acetoacetic esters is preferably 35% by mass or less, and more preferably 30% by mass or less, based on the total amount of the curing agent (B) containing the acetoacetic esters. The content of acetoacetic esters is preferably 5% by mass or more, and more preferably 10% by mass or more, based on the total amount of the curing agent (B) containing the acetoacetic esters. This can improve the working environment and workability, and can provide a cured product with a desired hardness without bleeding.

[0025] In the present invention, it is necessary that the main agent (A) contains terpene hydrocarbons and the curing agent (B) contains acetoacetates, and in the opposite case, that is, when the main agent (A) contains acetoacetates and the curing agent (B) contains terpene hydrocarbons, it is difficult to obtain a cured product with good hardness without bleeding. Similarly, when the main agent (A) and the curing agent (B) both contain the same terpene hydrocarbons or acetoacetates, it is also difficult to obtain a cured product with good hardness without bleeding.

[0026] To obtain a cured product by, for example, casting using the two-component curing urethane resin composition of the present invention, as described above, the main agent (A) containing terpene hydrocarbons and the curing agent (B) containing acetoacetic esters are mixed. At this time, the mixing ratio of the main agent (A) containing terpene hydrocarbons and the curing agent (B) containing acetoacetic esters is suitably set to a mass ratio (A:B) of 1:1 to 1:1.5, preferably 1:1 to 1:1.2. After mixing the base resin (A) and the curing agent (B), the mixture is poured into a mold and cured to obtain a cured product. Curing is usually carried out at room temperature. In addition, since terpene hydrocarbons and acetoacetates are widely used as fragrance ingredients, the base agent (A) to which terpene hydrocarbons have been added and the hardener (B) to which acetoacetates have been added each have their own unique fragrance. This makes it possible to improve the working environment for casting and the like. On the other hand, after curing, as is clear from the bleeding confirmation test described below, the terpene hydrocarbons and acetoacetates hardly bleed out onto the surface of the cured product, so the odor from the cured product almost disappears within 1 to 2 days after curing, or even if there is an odor, it is very slight.

[0027] Regarding the timing of mixing the terpene hydrocarbons into the base agent (A) and the acetoacetic esters into the curing agent (B), they may be mixed together with other additives during the production of the base agent (A) and the curing agent (B), or they may be mixed into the base agent (A) and the curing agent (B) when the two-component curing type urethane resin composition is used (i.e., during curing). The terpene hydrocarbons and acetoacetate esters in the present invention are considered to function as solvents because they have excellent solubility, dispersibility, or affinity for the main agent (A) and the curing agent (B), respectively, and do not cause turbidity or phase separation during storage. In particular, the acetoacetate esters have a large stabilizing effect on the curing agent (B).

[0028] The two-component curing urethane resin composition of the present invention can be widely applied to conventional uses of polyurethanes, such as paints, adhesives, casting, etc. The two-component curing urethane resin composition of the present invention imposes little burden on the user and the surrounding environment, so that, for example, when making models such as figures by casting, an individual can easily do so, and therefore, it can be widely used as a hobby that can be enjoyed by the whole family. Furthermore, when used in paints and adhesives, it does not have the irritating odor of xylene and improves the working environment, making it suitable for use in construction and renovation work at homes, hospitals, nursing homes, schools, etc., thus contributing to society by eliminating the physical and environmental burden of solvents.

[0029] The two-component curing urethane resin composition of the present invention will be described below with reference to examples, but the present invention is not limited to the following examples. EXAMPLES

[0030] In the combinations shown in Table 1, terpene hydrocarbons were mixed into the base agent (A) and acetoacetate esters were mixed into the curing agent (B). A two-component curing polyurethane resin (product name: Finecast, solvent-free type, translucent) manufactured by RC Berg was used for the base agent (A) and curing agent (B). In this product, the base agent (A) contains polyether polyol, and the curing agent (B) contains polyisocyanate (4,4'-diphenylmethane diisocyanate). In addition, as a comparative example, a solvent other than terpene hydrocarbons and acetoacetate esters that was determined to be stable in the stability test described later was used (see Samples No. 11 to 13). In the comparative examples, the same components were added to the base agent (A) and curing agent (B). As a control, samples were prepared by mixing xylene with the base agent (A) and the hardener (B). [Table 1] The mixing ratio by mass of the main agent (A) / terpene hydrocarbons was 75 / 25. The mass ratio of the hardener (B) / acetoacetic esters was also 75 / 25. Samples No. 11 to No. 13 were also mixed in the same ratio. (Stability test of base agent (A) and hardener (B)) For the above samples No. 1 to 13, 20 g of each of the base agent (A) and hardener (B) made by mixing terpene hydrocarbons and acetoacetate esters in the above-mentioned ratios was left at room temperature for one week, and the presence or absence of turbidity or phase separation was visually determined. As a result, no turbidity or phase separation was observed in samples No. 1 to 13, and it was confirmed that they were stable. (Cure test) For the above samples Nos. 1 to 13 and the control, the base agent (A) and the curing agent (B) were mixed in a mass ratio of 1:1, and after mixing, the mixture was poured into a silicone resin mold and cured at room temperature. (Bleeding confirmation test of cured product) After hardening, the specimen was removed from the mold, and after 24 hours or more had passed at room temperature, a vertical line was drawn on the surface of the hardened specimen (80 mm long, 55 mm wide, 9 mm thick) with an oil-based marker (Zebra Corp.'s Mackie (registered trademark) extra-fine tip), and after 1 minute the line was wiped off with a cotton swab. If the lines could not be wiped off, it was judged that there was no bleeding, and if they could be wiped off, it was judged that there was bleeding. The results are shown in Figures 1A, 1B, and 1C. That is, in the cured products of Samples No. 1 to 10, as shown in Figures 1A and 1B, the marked lines were not wiped off with a cotton swab and were clear, equivalent to the control (xylene-added product). From this, the cured products of Samples No. 1 to 10 were judged to have no bleeding. In contrast, in Samples No. 11 to 13 shown in Figure 1C, when wiped off with a cotton swab, the marked lines became faint or disappeared, so they were judged to have a blade. Note that in Figures 1A, 1B, and 1C, the difference in color shading appears above and below the surface of the cured products due to the difference in the degree of light reflection caused by the shadow of the camera when photographing. (Painting stability) The surfaces of the cured products of Samples No. 1 to 13 and the control were coated with a primer to confirm the paint stability. Tamiya's Fine Surfacer L (light gray) was used as the primer, which was sprayed onto half of the surface of the cured products to check for stickiness. The stickiness was judged by touching with the finger. As a result, no stickiness was observed on the surfaces of the cured products of Samples No. 1 to 10, and they were equivalent to the control (xylene-added product). On the other hand, stickiness was observed in Samples No. 11 to 13. From this, it can be determined that the cured products of Samples No. 1 to 10 have excellent coating stability. It is presumed that the stickiness of Samples No. 11 to 13 is related to the occurrence of bleeding in the bleeding confirmation test described above. (Hardness test) The hardness of the cured products (length 80 mm, width 55 mm, thickness 9 mm) of Samples No. 1 to 13 and the control (xylene-added product) that had been cured for 24 hours or more were measured using a hardness tester (based on JIS K 7215). The results are shown in Table 2. [Table 2] From Table 2, the hardness of the cured products of samples No. 1 to No. 10 was within the range of 0.9 to 1.1 times that of the cured product of the control (product with xylene added), and was almost equivalent. In contrast, the hardness of the cured products of samples No. 12 to No. 13 was about 0.3 times that of the cured product of the control (product with xylene added), and was inferior in hardness. The cured product of sample No. 11 had a hardness almost equivalent to that of the control, but was inferior to the control and the cured products of samples No. 1 to No. 10 in the bleeding test and the dimensional stability test described in the next section. (Dimensional stability test) The surface dimensions (length x width) of the cured product were measured the day after curing and 30 days after curing at room temperature, and the area reduction rate was compared with that of the control (xylene-added product). The results are shown in Table 3. [Table 3] As can be seen from Table 3, the dimensional stability of the cured products of Samples No. 1 to 10 was almost equivalent to that of the control (xylene added product). In contrast, the dimensional stability of the cured products of Samples No. 11 to 13 was inferior to that of the control (xylene added product). EXAMPLES

[0031] The workability of producing a cured product using a two-component curing urethane resin composition was examined. The same two-component curing polyurethane resin (product name: Finecast, solvent-free type, translucent) manufactured by RC Berg Co., Ltd. as in Example 1 was used as the base agent (A) and curing agent (B). (Viscosity before mixing) As shown in Table 4, the viscosity was investigated when terpene hydrocarbons were mixed with the base agent (A) and acetoacetate esters were mixed with the hardener (B). The mixing ratio was 75 / 25 by mass for base agent (A) / terpene hydrocarbons, and 75 / 25 by mass for hardener (B) / acetoacetate esters. As a control, the viscosity was also investigated when xylene was mixed with the base agent (A) and hardener (B) in the same ratio as above. For the test, 20 mL of sample was placed in a syringe barrel (nozzle diameter: 2 mm) with the nozzle facing downwards, and the drip time until the entire amount flowed out of the nozzle was measured. The results are shown in Table 4. In this table, the xylene-added products show the magnification of each sample when the drip time of the sample of main agent (A) + xylene is set to 1.0. [Table 4] As shown in Table 4, the dripping time for each sample was within 60 seconds. It is believed that a dripping time of 60 seconds or less will not cause any significant problems in the mixing of the base agent (A) and the hardener (B). (Viscosity after mixing) The viscosity was confirmed immediately after mixing the base agent and the hardener. That is, the base agent (A) to which terpene hydrocarbons were added so that the ratio was 25% by mass of the total amount, and the hardener (B) to which acetoacetate esters were added so that the ratio was 25% by mass of the total amount were mixed in a mass ratio of 1:1, and immediately 20 mL of the mixed liquid was charged into a syringe barrel (diameter of outlet: 2 mm), and the time until the entire amount flowed out was measured at room temperature. In addition, as a control, a sample in which the same amount of xylene was added to the base agent (A) and hardener (B) was also tested in the same manner. The test results are shown in Table 5. In this table, the product with xylene added indicates the magnification of each sample when the dripping time of the xylene-added sample is set to 1.0. [Table 5] The drop time of the candidate solvent additive was approximately 1.5 times shorter than that of the xylene additive. (Time to reach maximum temperature) As in the above, the base agent (A) containing 25% by mass of terpene hydrocarbons and the curing agent (B) containing 25% by mass of acetoacetic esters were mixed in a 1:1 mass ratio, and the temperature change was measured immediately after mixing. The time to reach the maximum temperature was then compared with that of a xylene-added product. The cured state can be considered to have been reached when the maximum temperature is reached. Therefore, the time to reach the maximum temperature can be considered to be the pot life. For the measurements, a waterproof wireless thermometer SK-270WP-B made by Sato Keiryoki Seisakusho Co., Ltd. was used, and the sensor was inserted into the center of the sample to measure the temperature. The test results are shown in Table 6. In Table 6, the xylene-added specimens show the magnification of each specimen when the time it took for the xylene-added specimen to reach the maximum temperature was taken as 1. [Table 6] From Table 6, it can be seen that the time required for each sample to reach the maximum temperature was within the range of 0.8 to 1.1 times that of the xylene-added sample. These test results showed that each sample was comparable to the xylene-added sample in terms of viscosity and time to reach maximum temperature, and there were no problems with workability when actually pouring the samples into silicone resin molds. In addition, in each process of mixing the base resin (A) and the hardener (B) and pouring into the mold, each sample had a pleasant fragrance and did not have an irritating odor like the control (xylene), which improved the work environment and improved workability. EXAMPLES

[0032] As shown in the following patterns 1 and 2, two or more kinds of terpene hydrocarbons were mixed and added to the main agent (A), and two or more kinds of acetoacetate esters were mixed and added to the curing agent (B). The numerical values ​​indicate the ratio (mass%) to the total amount of the main agent (A) or the curing agent (B). The main agent (A) and the curing agent (B) used were the same two-component curing polyurethane resin (product name: Finecast, solvent-free type, translucent) manufactured by RC Berg as in Example 1. Pattern 1: [Main ingredient (A)] d-limonene 10%, α-pinene 10%, γ-terpinene 5% [Hardening agent (B)] Ethyl acetoacetate 10%, benzyl acetoacetate 10%, butyl acetoacetate 5% Pattern 2: [Main ingredient (A)] L-limonene 10%, caryophyllene 10%, myrcene 5% [Hardening agent (B)] 2-methoxyethyl acetoacetate 10%, allyl acetoacetate 10%, propyl acetoacetate 5% The bleeding and hardness of the obtained cured product were examined in the same manner as in Example 1. The results are shown in Table 7. [Table 7] From Table 7, it can be seen that there is no bleeding in either pattern 1 or 2, and the hardness is higher than that of the xylene-added product. Therefore, the terpene hydrocarbons and acetoacetate esters can be used alone or in combination of two or more types.

Claims

1. The present invention relates to a two-component curing type urethane resin composition comprising a base agent (A) containing a polyol and a curing agent (B) containing an isocyanate compound, The main agent (A) contains at least one terpene hydrocarbon selected from the group consisting of d-limonene, l-limonene, α-pinene, β-pinene, γ-terpinene, β-caryophyllene, 3-carene, myrcene, elemene, and ocimene; The curing agent (B) has the general formula: 【Chemistry 3】 (In the formula, R represents a linear or branched alkyl group having 1 to 4 carbon atoms, an allyl group, a 2-methoxyethyl group, or a benzyl group.) The two-component curing type urethane resin composition contains at least one acetoacetic ester represented by the following formula:

2. A method for producing a cured urethane resin product using a two-component curing type urethane resin composition containing a base agent (A) containing a polyol and a curing agent (B) containing an isocyanate compound, comprising the steps of: Adding at least one terpene hydrocarbon selected from the group consisting of d-limonene, l-limonene, α-pinene, β-pinene, γ-terpinene, β-caryophyllene, 3-carene, myrcene, elemene, and ocimene to the main agent (A); The curing agent (B) is a compound represented by the general formula: 【Chemistry 4】 (In the formula, R represents a linear or branched alkyl group having 1 to 4 carbon atoms, an allyl group, a 2-methoxyethyl group, or a benzyl group.) adding at least one acetoacetate ester represented by mixing the base agent (A) to which the terpene-based hydrocarbons have been added and the curing agent (B) to which the acetoacetic esters have been added, and curing the mixture.

3. A paint comprising the two-component curing urethane resin composition according to claim 1.

4. An adhesive comprising the two-component curing urethane resin composition according to claim 1.

5. A casting resin composition comprising the two-component curing urethane resin composition according to claim 1.

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