JP2013067757A - Plasticizer for urethane resin, composition for urethane resin using the same, and cured material thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasticizer for a urethane resin, which has excellent compatibility with a polyol and a polyisocyanate as raw materials of the urethane resin, and with the urethane resin as a reaction product thereof, and can reduce the solution viscosity and exhibits only a low heating loss as a blend thereof; and to provide a composition for a urethane resin and a cured material thereof.SOLUTION: The plasticizer for a urethane resin contains an ester compound obtained by esterification reacting an alkylene oxide addition (A) of a polyhydric alcohol (a) having the number (h) of hydroxyl groups in one molecule of the polyhydric alcohol (a) of 2 to 6, the number (c) of carbon atoms in one molecule thereof of 3 to 18, and having a specific relationship of and the number (c) of carbon atoms, with an aliphatic monocarboxylic acid (B) having the number of carbon atoms excluding carbonyl carbon of 4 to 15 or its anhydride. The composition for a urethane resin and a cured material contains the plasticizer.

Description

  The present invention relates to a plasticizer for urethane resin, a composition for urethane resin using the same, and a cured product thereof.

  Conventionally, an electrical insulating sealant called a sealing material or a potting material has been used for electrical and electronic parts for the purpose of protecting from an atmosphere containing moisture, dust, and the like, vibration, and impact. As the material, urethane resin is widely used because it has excellent insulating properties, flexibility, and is relatively inexpensive. In recent years, electrical devices are required to have heat resistance due to the high airtightness due to the reduction in size and weight and the increase in the amount of current used. From such a background, the heat resistance more than before is calculated | required also about the raw material used for it.

  For electrical insulation sealants, phthalate esters such as dioctyl phthalate (DOP) are mainly used because they are inexpensive and have excellent compatibility with various polyols that are raw materials for urethane resins. (For example, refer to Patent Document 1). However, phthalates such as DOP are considered to be endocrine disrupting chemical substances (environmental hormones), and there is a problem that their use is limited. In addition, phthalate ester is a relatively volatile substance, and there is a problem that the phthalate ester is volatilized due to the temperature rise of electric / electronic parts and the inside of electric / electronic equipment is contaminated.

  Further, as a plasticizer having heat resistance, for example, trimellitic acid ester, pyromellitic acid ester, and the like are known. However, these plasticizers are less volatile by heating, but have poor compatibility with urethane resins. Therefore, there is a problem that the viscosity does not decrease even when blended in a urethane resin composition.

  Furthermore, in order to solve these problems, a compound obtained by reacting a polyether with an isocyanate has been proposed as a plasticizer for a sealing material with a small heating loss in which the plasticizer volatilizes during heating (for example, Patent Document 2). reference.). However, this plasticizer also cannot effectively reduce the solution viscosity, has high heat loss, and lacks heat resistance.

  Accordingly, there has been a demand for a plasticizer for urethane resin that can easily adjust the viscosity of the electrical insulating sealant, is excellent in the effect of lowering the solution viscosity, and has little heating loss.

JP-A-7-109326 JP 2001-64505 A

  The problem to be solved by the present invention is excellent in compatibility with polyol, polyisocyanate, which is a raw material of urethane resin, and urethane resin produced by reaction of these, and by adding them, the viscosity of the solution is greatly increased. Another object of the present invention is to provide a urethane resin plasticizer that can be reduced and has little heat loss, a urethane resin composition using the same, and a cured product thereof.

  As a result of diligent research to solve the above problems, by using an ester compound obtained by esterifying a polyhydric alcohol alkylene oxide adduct and a specific aliphatic monocarboxylic acid as a plasticizer for a urethane resin. The solution viscosity of a urethane resin composition composed of polyol, polyisocyanate, inorganic filler, etc. is greatly reduced, and the heat loss of the cured product is found to have led to the present invention.

That is, the present invention provides an ester of an alkylene oxide adduct (A) of a polyhydric alcohol (a) and an aliphatic monocarboxylic acid (B) having 4 to 15 carbon atoms excluding the carbonyl carbon or an anhydride thereof. A plasticizer for urethane resin containing an ester compound obtained by the chemical reaction as an essential component,
The number of hydroxyl groups (h) in one molecule of the polyhydric alcohol (a) is in the range of 2-6, and the number of carbon atoms (c) in one molecule of the polyhydric alcohol (a) is in the range of 3-18. And the relationship between the number of hydroxyl groups (h) and the number of carbon atoms (c) is
When the number of hydroxyl groups (h) is 2, the number of carbon atoms (c) is in the range of 4 to 12,
When the number of hydroxyl groups (h) is 3, the number of carbon atoms (c) is in the range of 3 to 12,
When the number of hydroxyl groups (h) is 4, the number of carbon atoms (c) is in the range of 4 to 14,
When the number of hydroxyl groups (h) is 5, the number of carbon atoms (c) is in the range of 5 to 16, and
When the number of hydroxyl groups (h) is 6, it relates to a plasticizer for urethane resin, wherein the number of carbon atoms (c) is in the range of 6-18.

  According to the present invention, the polyol, polyisocyanate, which is a raw material of the urethane resin, is excellent in compatibility with the urethane resin produced by the reaction thereof, and the viscosity of the solution can be greatly reduced by blending with these, and A plasticizer for urethane resin with little heating loss, a composition for urethane resin using the same, and a cured product thereof can be provided.

The plasticizer for urethane resin of the present invention includes an alkylene oxide adduct (A) of a polyhydric alcohol (a), an aliphatic monocarboxylic acid (B) having 4 to 15 carbon atoms excluding carbonyl carbon, or the same. A plasticizer for urethane resin containing, as an essential component, an ester compound obtained by an esterification reaction with an anhydride, wherein the number of hydroxyl groups (h) in one molecule of the polyhydric alcohol (a) is 2-6. The number of carbon atoms (c) in one molecule of the polyhydric alcohol (a) is in the range of 3 to 18, and the relationship between the number of hydroxyl groups (h) and the number of carbon atoms (c) is ,
When the number of hydroxyl groups (h) is 2, the number of carbon atoms (c) is in the range of 4 to 12,
When the number of hydroxyl groups (h) is 3, the number of carbon atoms (c) is in the range of 3 to 12,
When the number of hydroxyl groups (h) is 4, the number of carbon atoms (c) is in the range of 4 to 14,
When the number of hydroxyl groups (h) is 5, the number of carbon atoms (c) is in the range of 5 to 16, and
When the number of hydroxyl groups (h) is 6, the number of carbon atoms (c) is in the range of 6-18.

The alkylene oxide adduct (A) of the polyhydric alcohol (a) used in the present invention is a compound obtained by adding alkylene oxide to the polyhydric alcohol (a). Details will be described below.
The number of hydroxyl groups (h) in one molecule of the polyhydric alcohol (a) used in the present invention is in the range of 2-6. Moreover, the carbon atom number (c) in 1 molecule of this polyhydric alcohol (a) is the range of 3-18. The number of hydroxyl groups (h) and the number of carbon atoms (c) have the following relationship.
(1) When the number of hydroxyl groups (h) is 2, the heat loss of the plasticizer for urethane resin of the present invention can be further suppressed, and the compatibility with the polyol, which is a raw material of the urethane resin, can be improved. The number of carbon atoms (c) is in the range of 4 to 12, more preferably in the range of 4 to 10. Examples of the polyhydric alcohol (a) having 2 (h) hydroxyl groups in one molecule and 4 to 12 carbon atoms (c) in one molecule include 2-methyl-1 , 3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,5-pentanediol, 2- Methyl-1,4-butanediol, 2,3-butanediol, 1,2-hexanediol, 1,4-hexanediol, 1,6-hexanediol, 2,5-hexanediol, neopentyl glycol, 1, Examples include 10-decanediol.
(2) In the case where the number of hydroxyl groups (h) is 3, it is possible to further suppress the heat loss of the plasticizer for urethane resin of the present invention and to improve the compatibility with the polyol as a raw material of the urethane resin. The number of carbon atoms (c) is in the range of 3 to 12, more preferably in the range of 3 to 10. Examples of the polyhydric alcohol (a) having 3 (h) hydroxyl groups in one molecule and 3 to 12 carbon atoms (c) in one molecule include glycerin, 1, 2 and 1, for example. , 3-butanetriol, 1,2,4-butanetriol, trimethylolethane, 1,2,5-pentanetriol, 2,3,4-pentanetriol, trimethylolpropane, 3-methylpentane-1,3 5-triol, 1,3,5-hexanetriol, 1,2,7-heptanetriol, 2-ethyl-1,2,3-hexanetriol, 1,2,8-octanetriol, 1,2,9- Nonantriol, 1,2,10-decanetriol and the like can be mentioned.
(3) When the number of hydroxyl groups (h) is 4, the heat loss of the plasticizer for urethane resin of the present invention can be further suppressed, and the compatibility with the polyol, which is a raw material of the urethane resin, can be improved. The number of carbon atoms (c) is in the range of 4-14, more preferably in the range of 4-12. Examples of the polyhydric alcohol (a) having 4 hydroxyl groups (h) in one molecule and 4 to 14 carbon atoms (c) in one molecule are 1, 1, 5 , 5-pentanetetraol, 1,2,5,6-hexanetetraol, diglycerin, ditrimethylolpropane, erythritol, pentaerythritol, 1,2,7,8-octanetetraol, 1,2,9,10 -Decantetraol, 1,2,13,14-tetradecanetetraol and the like.
(4) In the case where the number of hydroxyl groups (h) is 5, the weight loss by heating of the plasticizer for urethane resin of the present invention can be further suppressed, and the compatibility with the polyol which is a raw material of the urethane resin can be improved, The number of carbon atoms (c) is in the range of 5 to 16, more preferably in the range of 5 to 14. Examples of the polyhydric alcohol (a) having 5 hydroxyl groups (h) in one molecule and 5 to 16 carbon atoms (c) in one molecule include D-arabinitol, L -Arabinitol, ribitol, xylitol and the like.
(5) In the case where the number of hydroxyl groups (h) is 6, it is possible to further suppress the heat loss of the plasticizer for urethane resin of the present invention, and the compatibility with the polyol, which is a raw material of the urethane resin, can be improved. The number of carbon atoms (c) is in the range of 6-18, more preferably in the range of 6-16. Examples of the polyhydric alcohol (a) having 6 hydroxyl groups (h) in one molecule and 6 to 18 carbon atoms (c) in one molecule include dipentaerythritol and dulcitol. , Mannitol, sorbitol and the like.
These polyhydric alcohols can be used alone or in combination of two or more.

  The number of moles of alkylene oxide added to the polyhydric alcohol (a) is a good balance between the ability to reduce the solution viscosity of the urethane resin resin composition and the heat resistance (volatility resistance) of the plasticizer. The average is preferably 1 to 10 moles, more preferably 1 to 8 moles. Examples of the alkylene oxide include ethylene oxide, propylene oxide, 1,2-butylene oxide, 1,4-butylene oxide, and the like. Among these, ethylene oxide is preferable from the viewpoint of compatibility with the urethane resin. In order to adjust the compatibility with the urethane resin, propylene oxide, 1,2-butylene oxide, 1,4-butylene oxide or the like may be added to the polyhydric alcohol as a part of ethylene oxide. In addition, all addition of alkylene oxide etc. to a polyhydric alcohol can be manufactured by a conventional method. An example of preparation of an adduct by reaction of the polyhydric alcohol with alkylene oxide and the like, and preparation of an ester from the adduct will be specifically described below. First, a polyhydric alcohol and a catalyst (for example, alkali hydroxide, alkali metal salt of alcohol, alkali catalyst such as alkanolamine or acid catalyst such as tin tetrachloride and boron trifluoride) are charged into a pressure reactor, and the system The inside is replaced with an inert gas such as nitrogen. If necessary, the temperature in the system is raised to 80 to 120 ° C. with stirring for the purpose of suppressing the formation of by-products, and moisture in the system is removed under reduced pressure. Next, after raising the temperature in the system to 100 to 150 ° C., a predetermined amount of alkylene oxide is gradually injected and reacted. After completion of the reaction, unreacted alkylene oxide is removed by reducing the pressure or passing an inert gas as necessary. The alkali component contained in the obtained reaction product is removed with an adsorbent or neutralized with an acid, and if necessary, the system is kept at 80 to 120 ° C. under reduced pressure to remove moisture in the system. . Further, the adsorbent and the deposited salt are removed with a filter or the like. In this way, the polyhydric alcohol alkylene oxide adduct (A) is obtained. The ends of this compound are substantially all hydroxyl groups.

  As the alkylene oxide adduct (A) of the polyhydric alcohol, a commercially available product can be used. For example, in the case of an ethylene oxide adduct, as a trimethylolpropane adduct, “Brownon TMP-3, manufactured by Aoki Oil & Fat Co., Ltd. TMP-9, TMP-20 "as glycerin adducts," UNIOX G-450, G-750 "manufactured by NOF Corporation," Brownon GL-3, GL-9, GL- "manufactured by Aoki Oil & Fat Co., Ltd. 20, GL-26 ”as a diglycerin adduct,“ SC-E450, SC-E750, SC-E1000, SC-E1500, SC-E2000 ”manufactured by Sakamoto Yakuhin Kogyo Co., Ltd., and Aoki Yushi Kogyo as a sorbitol adduct. In the case of “Brownon 240” manufactured by Co., Ltd. and propylene oxide adduct, “Uniol TG-330, TG-1000, TG-2000” manufactured by the company, as diglycerin adduct, “Unilube DGP-700, GP-700F” manufactured by NOF Corporation, “SC-P400” manufactured by Sakamoto Pharmaceutical Examples of SC-P750, SC-P1000, SC-P1200, SC-P1600 "and sorbitol adducts include NOF Corporation" Uniol HS-1600D ".

  On the other hand, the aliphatic monocarboxylic acid (B) used in the present invention is a compound having one carboxyl group at the end of the alkylene group. Among these aliphatic dicarboxylic acids, an aliphatic monocarboxylic acid having 5 to 10 carbon atoms is preferable because compatibility with the urethane resin and its raw material can be further improved. Examples of such aliphatic monocarboxylic acids (B) include butanoic acid, hexanoic acid, heptanoic acid, octanoic acid, 2-ethylhexanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid and the like. Can be mentioned. Of these, hexanoic acid, heptanoic acid, octanoic acid, 2-ethylhexanoic acid, nonanoic acid, decanoic acid, and dodecanoic acid are preferred because of a good balance between compatibility with the resin and heat resistance. Moreover, the anhydride of the illustrated aliphatic monocarboxylic acid (B) can be used similarly. These aliphatic monocarboxylic acids (B) or anhydrides thereof can be used alone or in combination of two or more.

  The ester compound, which is an essential component of the plasticizer for urethane resin of the present invention, can be produced by charging the above raw materials into a reactor and causing a normal esterification reaction. Moreover, it is preferable to use an esterification catalyst for the purpose of promoting this esterification reaction.

  A metal or an organometallic compound can be used as the esterification catalyst. Specific examples include at least one metal or organometallic compound selected from the group consisting of Group 2, Group 4, Group 12, Group 13, Group 14 of the Periodic Table. More specifically, for example, metals such as titanium, tin, zinc, aluminum, zirconium, magnesium, hafnium, germanium; titanium tetraisopropoxide, titanium tetrabutoxide, titanium oxyacetylacetonate, tin octoate, 2-ethyl Examples thereof include metal compounds such as hexanetin, acetylacetonate zinc, zirconium tetrachloride, zirconium tetrachloride tetrahydrofuran complex, hafnium tetrachloride, hafnium tetrachloride, hafnium tetrachloride complex, germanium oxide, and tetraethoxygermanium. Of these, titanium alcohols such as titanium tetraisopropoxide, titanium tetrabutoxide, and titanium oxyacetylacetonate have good reactivity, ease of handling, and storage stability of the ester compound obtained by the esterification reaction. Coxide is preferred.

  Further, the amount of the esterification catalyst used may be an amount that can control the esterification reaction and suppress the coloring of the resulting ester compound, and the total amount of the polyhydric alcohol and the monodicarboxylic acid. On the other hand, the range of 10 to 2,000 ppm is preferable, and the range of 20 to 1,000 ppm is more preferable.

  When the ester compound is produced, the esterification catalyst is added at the same time as the addition of the polyhydric alcohol alkylene oxide adduct (A) and the aliphatic monocarboxylic acid (B) to the reactor. Alternatively, it may be added during the temperature increase, or the esterification catalyst may be divided and added.

In the esterification reaction, the charge ratio of the polyhydric alcohol alkylene oxide adduct (A) to the aliphatic monocarboxylic acid (B) is 1 equivalent of the hydroxyl group of the polyhydric alcohol alkylene oxide adduct (A). As long as the carboxyl group of the aliphatic monocarboxylic acid (B) is 1 equivalent or more, it is not particularly limited. For example, the carboxyl group 1 of the alkylene oxide adduct (A) of polyhydric alcohol What is necessary is just to adjust so that the equivalent of the carboxyl group of the said aliphatic monocarboxylic acid (B) may be the range of 1.00-1.50 with respect to an equivalent, Preferably it is the range of 1.01-1.30.
Moreover, reaction temperature at the time of manufacturing the said ester compound accelerates | stimulates reaction, suppressing that each raw material evaporates and sublimates, and can suppress thermal decomposition and coloring of the ester compound produced | generated by reaction, 60-300 The range of ° C is preferred, and the range of 100 to 250 ° C is more preferred.

  The ester compound obtained by the above production method is stable and resistant to hydrolysis even under high temperature and high humidity, and is difficult to cause bleed because of its good compatibility with the urethane resin described later, and to the effect of reducing the viscosity of the urethane resin solution. In order to be excellent, those having a hydroxyl value of 30 or less and an acid value of 2 or less are preferred, those having a hydroxyl value of 20 or less and having an acid value of 1 or less are more preferred.

  The urethane resin composition of the present invention is a composition containing a polyol, a polyisocyanate, an inorganic filler, and the urethane resin plasticizer of the present invention.

  The polyol which is one component of the composition for urethane resin of the present invention is a compound having two or more hydroxyl groups in one molecule. As this polyol, polyolefin polyol, polyether polyol, polyester polyol etc. are mentioned, for example.

  As the polyolefin polyol, for example, a diene compound such as butadiene and isoprene and, if necessary, styrene, acrylonitrile and the like are polymerized in the presence of an anionic polymerization catalyst such as metal lithium, metal potassium and metal sodium, and then ethylene. Polyols obtained by addition polymerization of alkylene oxides such as oxide and propylene oxide; Polyols obtained by radical polymerization of the diene compound with a radical initiator having a hydroxyl group such as hydrogen peroxide; Hydrogenation of these polyols And the like. These polyolefin polyols can be used alone or in combination of two or more.

  Examples of the polyether polyol include compounds having 2 to 3 hydroxyl groups in the molecule, such as ethylene glycol, propylene glycol, glycerin, trimethylolpropane, etc., alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, or the like. And polytetramethylene glycol obtained by polymerizing tetrahydrofuran in the presence of an alkaline catalyst, and polytetramethylene glycol obtained by polymerizing tetrahydrofuran in the presence of a cationic catalyst. These polyether polyols can be used alone or in combination of two or more.

  Examples of the polyester polyol include polycondensation reaction of dibasic acid and polyhydric alcohol, ring-opening polymerization of caprolactone or transesterification reaction of alkylene carbonate and glycol. Specific examples include dimer acid diol and sebacic acid. And other polyol compounds such as castor oil, hydrogenated castor oil, castor oil transesterification product, and the like.

  Examples of polyols other than those described above include 1,2-propylene glycol, dipropylene glycol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,2-pentanediol, 2,3-pentanediol, 2,5-hexanediol, 2,4-hexanediol, 2-ethyl-1,3-hexanediol, cyclohexanediol, glycerin, N, N-bis-2-hydroxypropylaniline, N , N′-bishydroxyisopropyl-2-methylpiperazine, propylene oxide adduct of bisphenol A, ethylene glycol, diethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6 -Hexanediol, heptanediol, Kutanjioru, trimethylolpropane, pentaerythritol, dipentaerythritol, tetrahydrofuran / alkylene oxide copolymer polyol, epoxy resin-modified polyols, partially saponified ethylene - vinyl acetate copolymer and hydrogenated compounds of these compounds.

  Further, carbonate diol may be used as the polyol, and examples thereof include α, ω-poly (hexamethylene carbonate) diol, α, ω-poly (3-methyl-pentamethylene carbonate) diol, and the like. Examples of these commercially available products include “PLACELCD-205”, “PLACEL205PL”, “PLACEL205HL”, “PLACEL210”, “PLACEL210PL”, “PLACEL210HL”, “PLACEL220],“ PLACEL220PL ”,“ PLACEL220HL ”manufactured by Daicel Chemical Industries, Ltd. Is mentioned.

  Among the polyols such as the polyolefin polyol, polyether polyol, and polyester polyol, polyolefin polyol is preferable because of high crack resistance and long life, and polybutadiene polyol, polyisoprene diol, hydrogenated polyisoprene diol, hydrogenated polybutadiene. Diols are more preferred. Examples of commercially available products of polybutadiene polyol include “PolybdR-15HT” and “PolybdR-45HT” manufactured by Idemitsu Petrochemical Co., Ltd., and “Polyip” manufactured by Idemitsu Petrochemical Co., Ltd. as commercially available products of polyisoprene diol. As a commercially available product of hydrogenated polyisoprene diol, “Epol” manufactured by Idemitsu Petrochemical Co., Ltd. may be mentioned. These polyols can be used alone or in combination of two or more.

  The polyisocyanate which is one component of the urethane resin composition of the present invention is a compound having two or more isocyanate groups in one molecule. Examples of the polyisocyanate include tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), carbodiimide-modified diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, phenylene diisocyanate, naphthalene-1,5-diisocyanate, o-toluidine diisocyanate, and triphenyl. Aromatic polyisocyanates such as methane triisocyanate, tris (isocyanatephenyl) thiophosphate, isopropylbenzene-2,4-diisocyanate; aliphatic-aromatic poly, such as xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI) Isocyanate, hexamethylene diisocyanate, dodecane diisocyanate, lysine Aliphatic polyisocyanates such as isocyanate, lysine ester triisocyanate, 1,6,11-undecane triisocyanate, 1,8-diisocyanate-4-isocyanate methyloctane, 1,3,6-hexamethylene triisocyanate, trimethylhexamethylene diisocyanate Transtranscyclohexane-1,4-diisocyanate, bicycloheptane triisocyanate, isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (hydrogenated MDI), hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated tetramethylxylylene diisocyanate, etc. An alicyclic polyisocyanate; a cyclized trimer of said polyisocyanate compound (modified isocyanurate) , And modified burette, ethylene glycol, 1,4-butanediol, propylene glycol, dipropylene glycol, trimethylolpropane, polyether polyol, polymer polyol, polytetramethylene ether glycol, polyester polyol, acrylic polyol, polyalkadiene Examples thereof include polyols, hydrides of polyalkadiene polyols, partially saponified ethylene-vinyl acetate copolymers, addition reaction products of polyisocyanate compounds with polyol compounds such as castor oil-based polyols, and the like. These polyisocyanates can be used alone or in combination of two or more.

  In addition, the isocyanate groups of the polyisocyanates exemplified above are phenolic compounds, oxime compounds, imide compounds, mercaptan compounds, alcohols, ε-caprolactam, ethyleneimine, α-pyrrolidone, diethyl malonate, sodium hydrogensulfite, boron. A blocked isocyanate blocked with a blocking agent such as an acid can also be used. Among these isocyanates, those which are liquid at normal temperature are preferable because of their good handling properties and mixing properties.

  The polyisocyanate is preferably used in an amount of 0.8 to 1.2 equivalents per 1 equivalent of the polyol compound.

  The compounding amount in the urethane resin composition of the plasticizer for urethane resin of the present invention is various, such as sufficient viscosity reduction of the urethane resin composition, sufficient flexibility and strength of the cured product of the urethane resin composition. From the viewpoint of obtaining physical properties, the range of 1 to 30% by weight is preferable, the range of 3 to 20% by weight is more preferable, and the range of 5 to 15% by weight is more preferable.

  If the plasticizer for urethane resins of the present invention is a urethane resin that is cured by a reaction between an isocyanate group and a hydroxyl group or amino group abrasive, the performance can be effectively exhibited. This urethane resin may be a foamed urethane foam or the like obtained by a known method.

  Examples of the inorganic filler that is one component of the urethane resin composition of the present invention include fume silica, precipitated silica, crystalline silica, hydrated alumina, aluminum hydroxide, anhydrous silicic acid, hydrous silicic acid, carbon black, and calcium carbonate. , Magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium oxide, bentonite, organic bentonite, ferric oxide, chromium oxide, cobalt, ferrite, zinc oxide, activated zinc white, shirasu balloon, glass fiber, filament, etc. Can be mentioned. These inorganic fillers may be oriented with shear in order to effectively exhibit their heat dissipation properties, or may be oriented by magnetic force if they are magnetic. Among these, alumina, silica, and iron oxide are preferable because of excellent heat dissipation.

  The blending amount of the inorganic filler in the urethane resin composition is such that sufficient thermal conductivity is obtained, viscosity becomes high in handling properties, and flame retardancy, thermal conductivity, etc. can be sufficiently improved. The range of mass% is preferable, the range of 20 to 80 mass% is more preferable, and the range of 40 to 70 mass% is more preferable.

  In the urethane resin composition of the present invention, a known plasticizer other than the urethane resin plasticizer of the present invention may be used in combination as long as the effects of the present invention are not impaired. When other plasticizers are used in combination, it is preferable to use a plasticizer that does not have a hydroxyl group because elasticity can be imparted to the cured product and viscosity can be reduced during preparation of the composition. Examples of such plasticizers include trimellitate plasticizers such as triethylhexyl trimellitate and triisodecyl trimellitate; pyromellitic plasticizers such as tetraethylhexyl pyromellitate and tetraisodecyl pyromellitate; Examples thereof include phosphoric acid esters such as dysphosphate, trisylenyl phosphate, cresyl diphenyl phosphate, xylenyl phosphate, and triphenyl phosphate, and polyester. However, it is preferable that the compounding quantity of these plasticizers is half or less of the total compounding quantity of the plasticizer mix | blended in the composition for urethane resins of this invention.

  Moreover, you may mix | blend a catalyst with the composition for urethane resins of this invention for acceleration | stimulation of hardening reaction. Examples of the catalyst include dibutyltin dilaurate (DTD), alkyl titanate, organosilicon titanate, stannous octoate, lead octylate, zinc octylate, bismuth octylate, bismuth neodecanoate, and dibutyltin diortho. Metal-based catalysts such as reaction products of phenylphenoxide, tin oxide and ester compounds (dioctyl phthalate, etc.), monoamines (triethylamine, etc.), diamines (N, N, N ′, N′-tetramethylethylenediamine, etc.), Examples include amine catalysts such as triamines (N, N, N ′, N ″, N ″ -pentamethyldiethylenetriamine and the like) and cyclic amines (triethylenediamine and the like). These catalysts can be used alone or in combination of two or more.

The cured product of the urethane resin composition of the present invention, that is, the urethane resin can be obtained by adding a curing agent to the composition and heating it. As said hardening | curing agent, the thing similar to above-mentioned polyisocyanate can be used.
The curing conditions of the urethane resin composition of the present invention are not particularly limited, but the composition is defoamed with a defoaming device using reduced pressure, centrifugal force, etc., and then poured into an object, which is 50 to 100 ° C. The method of heating in the range is mentioned.

  Since the plasticizer for urethane resins of the present invention can effectively reduce the viscosity of the urethane resin solution, it not only improves handling properties but also has excellent heat resistance, so that the plasticizer has little heat loss. From this, it can be used for a urethane resin-based resin composition that requires heat resistance. Applications include sealing agents, sealing agents, potting agents, coating agents, condensers and converter insulating materials used to protect against moisture and moisture. More specifically, examples thereof include electronic washing machines, toilet seats, water heaters, water purifiers, baths, electronic washing machines, electronic parts used in electric tools, automobiles, motorcycles, and the like. Moreover, the urethane-type member for the purpose of soundproofing, vibration proofing, and heat dissipation is mentioned. More specifically, examples thereof include motors for transportation equipment such as automobiles, soundproofing, vibration proofing, and heat radiating members for engines.

  Hereinafter, the present invention will be described in more detail with reference to examples. The properties of the plasticizer, acid value, hydroxyl value and viscosity were measured under the following conditions.

[Observation of properties]
A sample was put in a transparent container, and the properties were visually observed.

[Measurement conditions of acid value]
The measurement was performed according to JIS K 0070-1992.

[Measurement conditions for hydroxyl value]
The measurement was performed according to JIS K 0070-1992.

[Measurement conditions for viscosity]
After 90 g of a sample for measuring viscosity is put into a 100 ml glass bottle, using a rotational viscometer (“TRV101F” manufactured by Toki Sangyo Co., Ltd.) whose liquid temperature is set at 25 ° C., depending on the viscosity range of the sample, Viscosity was measured under each condition.
Plasticizer; Rotor No. 1. Rotation speed 12rpm (upper limit 500mPa · s)
Polyol solution: Rotor No. 2. Rotation speed 30rpm (upper limit 1000mPa · s)
Urethane resin solution: Rotor No. 4, 6 rpm (upper limit 10 Pa · s)

  Plasticizers were produced or prepared according to Examples 1 to 9 and Comparative Examples 1 to 8 below.

Example 1
2-ethylhexanoic acid (“Octylic acid” manufactured by Kyowa Hakko Chemical Co., Ltd.); hereinafter referred to as “2-EHA” Abbreviated as “.” And 345.6 g, a polyhydric alcohol obtained by adding an average of 10 moles of ethylene oxide to neopentyl glycol (average number of moles of ethylene oxide added per hydroxyl group; hereinafter referred to as “NPG-EO10”) Abbreviated to 544 g) and 0.27 g of titanium tetraisopropoxide (hereinafter abbreviated as “TiPT”), and then nitrogen gas is maintained at a tower top temperature of 100 ° C. or lower so that the temperature is 100 to 500 ml / While blowing in the range of minutes, the temperature was raised to 240 ° C. Next, a dehydration esterification reaction was performed while removing water generated at 240 ° C. When the acid value of the reaction product became 2 or less, 0.18 g of 85% by mass aqueous phosphoric acid solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the reduced pressure was released and the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (1). The ester compound (1) had an acid value of 0.3, a hydroxyl value of 1.5, and a viscosity of 57 mPa · s.

(Example 2)
A multi-layered 4-liter flask with an internal volume of 1 L equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a fractional distillation tube, 518.4 g of 2-EHA, and an average of 3 mol of ethylene oxide added to trimethylolpropane After charging 266 g of alcohol (average number of moles of ethylene oxide added per hydroxyl group; hereinafter abbreviated as “TMP-EO3”) and 0.24 g of TiPT, nitrogen gas was added at a tower top temperature of 100. The temperature was raised to 240 ° C. while blowing in the range of 100 to 500 ml / min so as to maintain the temperature at or below. Next, a dehydration esterification reaction was performed while removing water generated at 240 ° C. When the acid value of the reaction product became 2 or less, 0.19 g of 85% by mass aqueous phosphoric acid solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the reduced pressure was released, the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (2). The ester compound (2) had an acid value of 0.1, a hydroxyl value of 6.1, and a viscosity of 52 mPa · s.

(Example 3)
Polyhydric alcohol in which 378 g of 2-EHA and an average of 9 moles of ethylene oxide were added to trimethylolpropane were added to a 1 L four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube and a trough tube. The average number of moles of ethylene oxide added per hydroxyl group is 3; hereinafter abbreviated as “TMP-EO9”), and 371 g of TiPT and 0.22 g of TiPT are added, and then the top temperature of the tower is 100 ° C. or less. The temperature was raised to 240 ° C. while blowing in the range of 100 to 500 ml / min. Next, a dehydration esterification reaction was performed while removing water generated at 230 ° C. When the acid value of the reaction product became 2 or less, 0.18 g of 85% by mass aqueous phosphoric acid solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the reduced pressure was released and the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (3). The ester compound (3) had an acid value of 0.4, a hydroxyl value of 5.3, and a viscosity of 77 mPa · s.

Example 4
Polyhydric alcohol in which 364 g of 2-EHA and an average of 20 mol of ethylene oxide are added to trimethylolpropane in a four-necked flask with an internal volume of 1 L equipped with a thermometer, a stirrer, a nitrogen introducing tube and a trough tube for fractional distillation ( The average number of moles of ethylene oxide added per hydroxyl group was 6.7; hereinafter abbreviated as “TMP-EO20”) and 186.1 g of TiPT and 0.17 g of TiPT, and then nitrogen gas was added to the top of the column. The temperature was raised to 240 ° C. while blowing in the range of 100 to 500 ml / min so as to maintain the temperature at 100 ° C. or lower. Next, a dehydration esterification reaction was performed while removing water generated at 240 ° C. When the acid value of the reaction product became 2 or less, 0.13 g of 85% by mass phosphoric acid aqueous solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the reduced pressure was released and the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (4). The ester compound (4) had an acid value of 0.1, a hydroxyl value of 5.0, and a viscosity of 154 mPa · s.

(Example 5)
To a 1 L four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube and a trough tube for fractional distillation, n-hexanoic acid (“n-hexanoic acid” manufactured by Kanto Chemical Co., Inc .; hereinafter referred to as “HA”) Is abbreviated to 250.6 g, TMP-EO9 is 318.0 g, and TiPT is 0.17 g, and then nitrogen gas is maintained at a tower top temperature of 100 ° C. or less at 100 to 500 ml / min. The temperature was raised to 240 ° C. while blowing in the range. Next, a dehydration esterification reaction was performed while removing water generated at 240 ° C. When the acid value of the reaction product became 2 or less, 0.12 g of 85% by mass phosphoric acid aqueous solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the reduced pressure was released, the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (5). The ester compound (5) had an acid value of 0.2, a hydroxyl value of 5.8, and a viscosity of 85 mPa · s.

(Example 6)
Dodecanoic acid ("NAA-122" manufactured by NOF Corporation); hereinafter abbreviated as "DA" is added to a 1 L four-necked flask equipped with a thermometer, a stirrer, a nitrogen introduction tube and a trough tube for fractional distillation. ) 396 g, TMP-EO9 318 g, and TiPT 0.21 g, and then nitrogen gas was blown in a range of 100 to 500 ml / min so as to maintain the tower top temperature at 100 ° C. or lower, and 240 ° C. The temperature was raised to. Next, a dehydration esterification reaction was performed while removing water generated at 240 ° C. When the acid value of the reaction product became 2 or less, 0.15 g of 85% by mass phosphoric acid aqueous solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the reduced pressure was released, the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (6). The ester compound (6) had an acid value of 0.2, a hydroxyl value of 4.8, and a viscosity of 95 mPa · s.

(Example 7)
Polyhydric alcohol (hydroxyl group 1) having an average of 9 mol of ethylene oxide added to 324 g and glycerin to a 1 L four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a trough tube for fractional distillation. After adding 292.8 g of average added mole number of ethylene oxide per unit; hereinafter abbreviated as “GL-EO9” and 0.19 g of TiPT, the top temperature of the tower was 100 ° C. or less. The temperature was raised to 240 ° C. while blowing in the range of 100 to 500 ml / min. Next, a dehydration esterification reaction was performed while removing water generated at 240 ° C. When the acid value of the reaction product became 2 or less, 0.15 g of 85% by mass phosphoric acid aqueous solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the pressure was reduced and the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (7). The ester compound (7) had an acid value of 0.3, a hydroxyl value of 4.8, and a viscosity of 80 mPa · s.

(Example 8)
A polyhydric alcohol in which 345.6 g of 2-EHA and an average of 8 mol of ethylene oxide are added to pentaerythritol are added to a 1 L four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube and a trough tube for fractional distillation. (The average number of moles of ethylene oxide added per hydroxyl group: 2; hereinafter abbreviated as “PE-EO8”) was charged with 244 g and TiPT of 0.18 g, and then nitrogen gas was added at a top temperature of 100 ° C. While maintaining the following, the temperature was raised to 240 ° C. while blowing in the range of 100 to 500 ml / min. Next, a dehydration esterification reaction was performed while removing water generated at 240 ° C. When the acid value of the reaction product became 2 or less, 0.14 g of 85% by mass phosphoric acid aqueous solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the reduced pressure was released, the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (8). The ester compound (8) had an acid value of 0.5, a hydroxyl value of 2.5, and a viscosity of 93 mPa · s.

Example 9
A polyhydric alcohol in which 414.2 g of 2-EHA and an average of 8 moles of ethylene oxide are added to diglycerin in a 1 L four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube and a T-shaped tube for fractional distillation (The average number of moles of ethylene oxide added per hydroxyl group: 2; hereinafter abbreviated as “DGL-EO8”) was charged with 270.2 g and TiPT with 0.20 g. The temperature was raised to 240 ° C. while blowing in the range of 100 to 500 ml / min so as to maintain at 100 ° C. or lower. Next, a dehydration esterification reaction was performed while removing water generated at 240 ° C. When the acid value of the reaction product became 2 or less, 0.17 g of 85% by mass phosphoric acid aqueous solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the reduced pressure was released and the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (9). The ester compound (9) had an acid value of 0.5, a hydroxyl value of 9.0, and a viscosity of 77 mPa · s.

(Comparative Example 1)
As an ester compound of Comparative Example 1, di-2-ethylhexyl phthalate (manufactured by DIC Corporation; hereinafter, abbreviated as “DOP”) was prepared. This ester compound was a transparent liquid and had an acid value of 0.3, a hydroxyl value of 2, and a viscosity of 57 mPa · s.

(Comparative Example 2)
As an ester compound of Comparative Example 2, tri-2-ethylhexyl trimellitate (“Monicizer W-700” manufactured by DIC Corporation; hereinafter abbreviated as “TOTM”) was prepared. This ester compound was a transparent liquid, and had an acid value of 0.4, a hydroxyl value of 2.0, and a viscosity of 206 mPa · s.

(Comparative Example 3)
As the ester compound of Comparative Example 3, tetra-2-ethylhexyl pyromellitate ("Monocizer W-7010" manufactured by DIC Corporation; hereinafter abbreviated as "TOPM") was used. This ester compound was a transparent liquid and had an acid value of 0.6, a hydroxyl value of 3.0, and a viscosity of 392 mPa · s.

(Comparative Example 4)
In a 3 L four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube and a trough for fractional distillation, 633.6 g of 2-EHA, polyethylene glycol (average number of added moles of ethylene oxide 13; Abbreviated as “PEG”), and 0.18 g of TiPT were charged, and then nitrogen gas was blown in the range of 100 to 500 ml / min so as to maintain the tower top temperature at 100 ° C. or lower, and 230 ° C. The temperature was raised to. Next, a dehydration esterification reaction was performed while removing water generated at 230 ° C. When the acid value of the reaction product became 2 or less, 0.12 g of 85 mass% phosphoric acid aqueous solution was charged, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 230 ° C., and toluene and unreacted alcohol Was removed. After the outflow of toluene and unreacted alcohol ceased, the reduced pressure was released and the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (10). The ester compound (10) had an acid value of 0.9, a hydroxyl value of 5.5, and a viscosity of 72 mPa · s.

(Comparative Example 5)
Into a 3 L four-necked flask equipped with a thermometer, a stirrer, and a nitrogen introduction tube, 726 g of polypropylene glycol monobutyl ether (average added mole number of propylene oxide: 5; hereinafter abbreviated as “PPO-MB”) and tri 165 g of diisocyanate (hereinafter abbreviated as “TDI”) was charged and reacted at 80 ° C. for 10 hours to obtain a urethane compound (1). The urethane compound (1) had an acid value of 0.1, a hydroxyl value of 10, and a viscosity of 118 mPa · s.

(Comparative Example 6)
Polyhydric alcohol in which 309.6 g of 2-EHA and 10 mol of ethylene oxide on average in propylene glycol were added to a 1 L four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube and a T-tube for fractional distillation. (The average number of moles of ethylene oxide added per hydroxyl group: 5; hereinafter abbreviated as “PG-EO10”) was charged with 190 g and 0.15 g of TiPT. While maintaining the following, the temperature was raised to 240 ° C. while blowing in the range of 100 to 500 ml / min. Next, a dehydration esterification reaction was performed while removing water generated at 240 ° C. When the acid value of the reaction product became 2 or less, 0.11 g of 85% by mass phosphoric acid aqueous solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the reduced pressure was released and the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a white solid ester compound (11). The ester compound (11) had an acid value of 0.5 and a hydroxyl value of 2.5.

(Comparative Example 7)
Into a 1 L four-necked flask equipped with a thermometer, stirrer, nitrogen inlet tube and fractional distillation tube, propanoic anhydride (“propionic anhydride” manufactured by Kanto Chemical Co., Inc .; hereinafter abbreviated as “PA”) 31) g, 371.0 g of TMP-EO9, and 6.9 g of triethylamine (manufactured by Kanto Chemical Co., Inc.) were charged, and the temperature was raised to 90 ° C. while paying attention to heat generation. Subsequently, the esterification reaction was performed by stabilizing at 90 ° C. until the exothermic reaction settled. One hour after the exotherm subsided, the pressure was reduced to 0.67 kPa or less to remove unreacted carboxylic acid. After the unreacted carboxylic acid flowed out, the reduced pressure was released and the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a transparent liquid ester compound (12). The ester compound (12) had an acid value of 0.2, a hydroxyl value of 0.6, and a viscosity of 55 mPa · s.

(Comparative Example 8)
Octadecanoic acid ("Lunac S-90V" manufactured by Kao Corporation; hereinafter abbreviated as "ODA") is added to a 1 L four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube and a trough tube for fractional distillation. 375.5 g, TMP-EO9 212.0 g, and TiPT 0.18 g, and then nitrogen gas was blown in the range of 100 to 500 ml / min so as to maintain the top temperature at 100 ° C. or lower. The temperature was raised to 240 ° C. Next, a dehydration esterification reaction was performed while removing water generated at 230 ° C. When the acid value of the reaction product became 2 or less, 0.11 g of 85% by mass phosphoric acid aqueous solution was added, pressure reduction was started, the pressure was reduced to 0.67 kPa or less at 240 ° C., and unreacted carboxylic acid Was removed. After the unreacted carboxylic acid flowed out, the reduced pressure was released and the temperature was lowered, and the reaction product was filtered out through diatomaceous earth to obtain a white solid ester compound (13). The ester compound (13) had an acid value of 1.0 and a hydroxyl value of 9.5.

  About the plasticizer manufactured or prepared in said Examples 1-9 and Comparative Examples 1-8, the raw material and the characteristic value were put together in Table 1 and 2. FIG.

In addition, the symbol in Table 2 represents the following.
2-EHOH: 2-ethylhexyl alcohol PA: phthalic anhydride TMA: trimellitic anhydride PMA: pyromellitic anhydride

(Example 10)
The following evaluation was performed using the ester compound (1) produced in Example 1 above.

[Evaluation of compatibility with polyol]
100 parts by mass of polybutadiene polyol (“R-45HT” manufactured by Idemitsu Kosan Co., Ltd .; number average molecular weight: 2,800, functional group number: 2.3, iodine value: 398, hydroxyl value: 46), castor oil-based polyol ( 70 parts by mass of “URIC Y-403” manufactured by Ito Oil Co., Ltd .; hydroxyl value: 152, acid value: 1.5, and castor oil-based polyol (“URIC H-31” manufactured by Ito Oil Co., Ltd .; hydroxyl value: 160, acid value: 1.8) 30 parts by mass and 100 parts by mass of the ester compound (1) produced in Example 1 were mixed with a meniscus stirrer for 10 minutes. The appearance of the obtained solution was visually observed, and the compatibility was confirmed by the presence / absence of component separation and transparency. The compatibility was evaluated according to the following criteria.
○: There is no separation and it is transparent.
X: There exists separation or it is cloudy.

[Evaluation of viscosity reducing ability in polyol composition]
After 90 g of the solution prepared in the evaluation of compatibility with the above polyol was put into a glass bottle having a capacity of 100 cm ³ , a rotational viscometer (“TRV101F” manufactured by Toki Sangyo Co., Ltd .; rotor No. .3, rotational speed 60 rpm). From the obtained viscosity, the viscosity reduction ability with respect to the polyol was evaluated according to the following criteria. In addition, the viscosity measurement measured only the thing which was not separated in the external appearance of the mixed solution of a polyol and a plasticizer, and was transparent. The same applies to the following measurement and evaluation.
A: The viscosity is less than 500 mPa · s.
(Triangle | delta): A viscosity is 500 mPa * s or more and less than 800 mPa * s.
X: The viscosity is 800 mPa · s or more.

[Preparation of composition for urethane resin]
300 parts by mass of a solution prepared by evaluation of compatibility with the above polyol, and 500 parts by mass of spherical alumina (“DAM10” manufactured by Denki Kagaku Kogyo Co., Ltd .; volume average particle diameter 8.6 μm) as an inorganic filler. A composition for urethane resin was obtained by dispersing with a disper (model name “TK Homodisper 2.5” manufactured by PRIMIX Corporation) to obtain a uniform dispersion.

[Evaluation of ability to reduce viscosity in composition for urethane resin]
About the composition for urethane resins obtained above, the viscosity was measured with a rotational viscometer (manufactured by Toki Sangyo Co., Ltd. “TRV101F”; rotor No. 4, rotational speed 6 rpm) set at 25 ° C. From the obtained viscosity, the viscosity reduction ability with respect to the urethane resin composition was evaluated according to the following criteria.
A: The viscosity is less than 40 Pa · s.
○: The viscosity is 40 Pa · s or more and less than 60 Pa · s.
Δ: The viscosity is 60 Pa · s or more and less than 80 Pa · s.
X: Viscosity is 80 Pa · s or more.

[Mixing of curing agent to urethane resin composition]
50 parts by mass of a curing agent (“Millionate MR-100” manufactured by Nippon Polyurethane Co., Ltd .; polyisocyanate component: Polymeric MDI) is added to 800 parts by mass of the urethane resin composition prepared above, and the mixture is mixed for 10 minutes with a stirrer equipped with a meniscus. After mixing, the pressure was reduced to 0.27 mPa and defoamed for 3 minutes to obtain a urethane resin composition containing a curing agent.

[Evaluation of heat loss resistance of cured product of urethane resin composition (urethane resin)]
5 g of the urethane resin composition containing the curing agent obtained above was poured into a metal petri dish having a diameter of 60 mm, and placed in a gear aging tester (“ACR Gear Oven” manufactured by Toyo Seiki Seisakusho Co., Ltd.). After curing at 4 ° C. for 4 hours, the resulting cured product was naturally cooled to room temperature to obtain a sample for evaluation of heat loss resistance. About this sample, mass was measured and it was set as the mass before a heating. Next, the sample whose mass before heating was measured was placed in a gear aging tester (“ACR Gear Oven” manufactured by Toyo Seiki Seisakusho Co., Ltd.), heated at 150 ° C. for 300 hours, and then naturally cooled to room temperature. The mass was measured again and used as the mass after heating. Using the obtained pre-heating mass and post-heating mass, the heating loss rate was calculated by the following formula (1).
Heating loss rate (%) = (mass before heating−mass after heating) / mass before heating × 100 (1)

From the value of the heating weight loss rate calculated above, the heat loss resistance was evaluated according to the following criteria.
○: The heating weight loss rate is less than 1%.
(Triangle | delta): A heating weight loss rate is 1% or more and less than 3%.
X: Heat loss rate is 3% or more.

[Measurement of Shore Hardness of Cured Product (Urethane Resin) of Urethane Resin Composition]
20 g of urethane resin composition containing the curing agent obtained above was poured into a metal petri dish with a diameter of 60 mm, and placed in a gear aging tester (“ACR Gear Oven” manufactured by Toyo Seiki Seisakusho Co., Ltd.). After curing at 4 ° C. for 4 hours, the resulting cured product was naturally cooled to room temperature to obtain a sample for measuring the Shore hardness. Next, according to JIS K 6253, the Shore hardness of the obtained sample was measured using an Asker A type hardness meter (manufactured by Kobunshi Keiki Co., Ltd.).

[Bleedability test of cured product (urethane resin) of urethane resin composition]
20 g of urethane resin composition containing the curing agent obtained above was poured into a metal petri dish with a diameter of 60 mm, and placed in a gear aging tester (“ACR Gear Oven” manufactured by Toyo Seiki Seisakusho Co., Ltd.). After curing at 4 ° C. for 4 hours, the resulting cured product was naturally cooled to room temperature and cut into 20 × 20 mm to obtain a bleed-out confirmation sample. Next, the obtained sample was left in a hot air dryer set at 100 ° C. for 168 hours, and the state of bleeding of the ester compound (plasticizer) on the sample surface was visually observed and evaluated according to the following criteria.
○: No bleed △: Partial bleed ×: Bleeding occurs and defective

(Examples 11-18 and Comparative Examples 9-16)
The same operations as in Example 10 were performed on the ester compounds (plasticizers) produced or prepared in Examples 2 to 9 and Comparative Examples 1 to 8, and evaluated.

  The results of the above measurement and evaluation are shown in Tables 3 and 4.

  From the evaluation results of Examples 10 to 18 shown in Table 3, the urethane resin plasticizer of the present invention has good compatibility with the polyol, and the urethane resin composition using the urethane resin plasticizer of the present invention. Since the product has a low viscosity, it was found that the product was excellent in handling properties. Moreover, it turned out that the hardened | cured material (urethane resin) of the composition for urethane resins using the plasticizer for urethane resins of this invention was excellent in heat resistance from showing the high heat loss-proof property.

  On the other hand, the following was found from the evaluation results of Comparative Examples 9 to 18 shown in Table 4.

  Comparative Examples 9 to 11 are examples using materials that have been widely used as plasticizers. In the example using DOP of Comparative Example 9, it was found that the viscosity of the urethane resin composition could be reduced to some extent, but there was a problem that the heating residual ratio was high and the heating loss was large. Further, in the example using TOTM in Comparative Example 10 and the example using TOPM in Comparative Example 11, the residual heat rate was relatively low and had good heat loss resistance, but the viscosity of the urethane resin composition It has been found that there is a problem that a low viscosity with good handling properties cannot be obtained.

  Comparative Example 12 is an example using an ester compound (10) obtained by reacting polyethylene glycol and a monocarboxylic acid, but the viscosity of the urethane resin composition can be reduced to a low viscosity with good handling properties. It has been found that there are problems that the residual heating rate is high, the heating loss is large, the bleed out occurs and the compatibility is low.

  Comparative Example 13 is an example in which a urethane compound is used as a plasticizer instead of an ester compound, but the viscosity of the urethane resin composition can be reduced to some extent, but the heating residual ratio is also high and the heating loss is large. I found out that

  In Comparative Example 14, the number of carbon atoms (c) and the number of hydroxyl groups (h) in one molecule of the polyhydric alcohol (a) (before addition of ethylene oxide), which is a raw material of the ester compound, is within the scope of the present invention (hydroxyl group). When the number (h) is 2, the ester compound (11) produced from the polyhydric alcohol deviating from the carbon atom number (c) in the range of 4 to 12 and having the carbon atom number (c) of 3 is obtained. It is an example used. Since this ester compound (11) is solid at room temperature, it was difficult to handle as a plasticizer, and the compatibility with polyol was poor, indicating that it could not be used as a plasticizer for urethane resin compositions.

  In Comparative Example 15, the aliphatic polyvalent carboxylic acid (B), which is a raw material of the ester compound, has an aliphatic polyvalent carboxylic acid (B) whose number of carbon atoms, excluding the carbonyl carbon, deviates from 4 to 15 which is the range of the present invention and is 2. This is an example using an ester compound (12) produced with carboxylic acid. Although this ester compound (12) can make the viscosity of the composition for urethane resins low viscosity with good handling properties, the residual heating rate is high, the heating loss is large, bleed out occurs, and the compatibility is low. It turns out that there is a problem.

  In Comparative Example 16, the number of carbon atoms excluding the carbonyl carbon of the aliphatic polycarboxylic acid (B) that is a raw material of the ester compound that is an essential component of the plasticizer for urethane resin of the present invention is out of the range of 4 to 15. , 17 is an example using an ester compound (13) produced with an aliphatic polyvalent carboxylic acid. Since this ester compound (13) is solid at room temperature, it was difficult to handle as a plasticizer, and the compatibility with the polyol was poor, indicating that it could not be used as a plasticizer for urethane resin compositions.

Claims (6)

Obtained by esterifying the alkylene oxide adduct (A) of the polyhydric alcohol (a) and the aliphatic monocarboxylic acid (B) having 4 to 15 carbon atoms excluding the carbonyl carbon or its anhydride. The plasticizer for urethane resin containing the obtained ester compound as an essential component, wherein the number of hydroxyl groups (h) in one molecule of the polyhydric alcohol (a) is in the range of 2 to 6, and the polyhydric alcohol ( The number of carbon atoms (c) in one molecule of a) is in the range of 3 to 18, and the relationship between the number of hydroxyl groups (h) and the number of carbon atoms (c) is
When the number of hydroxyl groups (h) is 2, the number of carbon atoms (c) is in the range of 4 to 12,
When the number of hydroxyl groups (h) is 3, the number of carbon atoms (c) is in the range of 3 to 12,
When the number of hydroxyl groups (h) is 4, the number of carbon atoms (c) is in the range of 4 to 14,
When the number of hydroxyl groups (h) is 5, the number of carbon atoms (c) is in the range of 5 to 16, and
When the number of hydroxyl groups (h) is 6, the number of carbon atoms (c) is in the range of 6-18.   The plasticizer for urethane resin according to claim 1, wherein the polyhydric alcohol (a) is at least one polyhydric alcohol selected from the group consisting of glycerin, diglycerin, neopentyl glycol and pentaerythritol.   The plasticizer for urethane resin according to claim 1, wherein the aliphatic monocarboxylic acid (B) is at least one aliphatic monocarboxylic acid selected from the group consisting of hexanoic acid, 2-ethylhexanoic acid and dodecanoic acid. .   The plasticizer for urethane resin according to claim 1, wherein the alkylene oxide is ethylene oxide.   It is a composition for urethane resins containing a polyol, polyisocyanate, an inorganic filler, and the plasticizer for urethane resins of any one of Claims 1-3, Comprising: For the said urethane resin in this urethane resin composition Content of a plasticizer is 1-30 mass%, The composition for urethane resins characterized by the above-mentioned.   A cured product obtained by adding a curing agent to the urethane resin composition according to claim 5 and curing the composition.