Polyol composition, urethane foam composition, urethane foam, and molded article

Abstract

The polyol composition contains 12 to 28 mass% of a first polyol, 12 to 28 mass% of a second polyol, and 52 to 68 mass% of a third polyol. The first polyol has an average number of functional groups of 1.5-4.5, an OH number of 20-50 mgKOH / g, and an oxyethylene group content of 10-60 mass%. The second polyol has an average number of functional groups of 1.5-4.5, an OH number of 20-70 mgKOH / g, and an oxyethylene group content of less than 10 mass%. The third polyol has an average number of functional groups of 1.5-4.5, an OH number of 120-300 mgKOH / g, and an oxyethylene group content of 10 mass% or more.

Description

Technical Field

[0001] This invention relates to polyol compositions, urethane foam compositions, polyurethane foams, and molded bodies. Background Technology

[0002] Polyurethane foam is obtained by reacting and foaming polyisocyanates and polyols in the presence of a catalyst and a foaming agent. Polyurethane foam is widely used in various industrial sectors.

[0003] For example, polyurethane foam is used as a cushioning material in furniture and bedding (hereinafter referred to as furniture and bedding). Examples of furniture and bedding include beds, mattresses, pillows, sofas, and cushions.

[0004] More specifically, flexible polyurethane foam can be cited as an example of a polyurethane foam. Among flexible polyurethane foams, polyurethane foams with excellent low resilience (low-resilience polyurethane foam) are preferred. That is, low-resilience polyurethane foam has excellent volume pressure dispersion properties, thus enabling it to effectively equalize the distribution of volume pressure. Therefore, low-resilience polyurethane foam is suitable for use as a cushioning material in furniture and bedding.

[0005] As a polyurethane foam, for example, a low-resilience urethane foam described in Patent Document 1 has been proposed. This low-resilience urethane foam is obtained by reacting a urethane foam composition. The urethane foam composition contains a polyol (a), a polyisocyanate (b), a catalyst (c), and a blowing agent (d). As the polyol (a), 40 parts by weight of polyol (a) (2) (a polyoxyalkylene polyol with an average functional group number of 3, a hydroxyl value of 34 mg KOH / g, and an oxypropylene content of 100% by weight) and 60 parts by weight of polyol (a) (9) (a polyoxyalkylene polyol with an average functional group number of 3, a hydroxyl value of 210 mg KOH / g, and an oxyethylene content of 30% by weight) are used. Furthermore, as the polyisocyanate (b), toluene diisocyanate is used (for example, see Patent Document 1 (Example 4) below).

[0006] In addition, as a polyurethane foam, a flexible polyurethane foam as described in Patent Document 2 has also been proposed. This flexible polyurethane foam is formed from the reactants of a foamed polyurethane composition. The foamed polyurethane composition contains at least a polyol component, an isocyanate component, and a blowing agent. As the polyol component, 60 parts by weight of polyether polyol (1) (average functional group number 3, hydroxyl value 167 mg KOH / g, ethylene oxide content 50% by weight), 20 parts by weight of polyether polyol (2) (average functional group number 3, hydroxyl value 50 mg KOH / g, ethylene oxide content 75% by weight), and 20 parts by weight of polyether polyol (3) (average functional group number 3, hydroxyl value 56 mg KOH / g, ethylene oxide content 0% by weight) are used. Furthermore, as the isocyanate component, diphenylmethane diisocyanate (MDI) is used (for example, see Patent Document 2 (Example 9) below).

[0007] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 11-286566 Patent Document 2: Japanese Patent Application Publication No. 2020-33553 Summary of the Invention

[0008] The problem that the invention aims to solve On the other hand, depending on the application of the polyurethane foam, sometimes an increase in resilience is required. More specifically, sometimes a further reduction in the resilience of the low-resilience urethane foam described in Patent Document 1 is required.

[0009] Furthermore, the flexible polyurethane foam described in Patent Document 2 sometimes lacks low resilience. Additionally, the following drawback exists: the hardness of the flexible polyurethane foam described in Patent Document 2 decreases significantly in lower temperature ranges (e.g., below 10°C).

[0010] Therefore, various industrial sectors require polyurethane foams that possess excellent low resilience and can suppress hardness changes in lower temperature regions.

[0011] The present invention relates to a polyol composition, a urethane foam composition obtained from the polyol composition, a polyurethane foam, and a molded body, wherein the polyol composition is capable of producing a polyurethane foam having excellent low resilience and suppressing hardness changes in a lower temperature region.

[0012] Methods for solving problems The present invention [1] includes a polyol composition comprising a first polyol, a second polyol, and a third polyol, wherein the first polyol has an average number of functional groups of 1.5 or more and 4.5 or less, the first polyol has a hydroxyl value of 20 mg KOH / g or more and 50 mg KOH / g or less, and the oxyethylidene unit at the molecular end of the first polyol comprises 10% by mass or more and 60% by mass relative to the total amount of oxyalkylene units of the first polyol; the second polyol has an average number of functional groups of 1.5 or more and 4.5 or less, the second polyol has a hydroxyl value of 20 mg KOH / g or more and 70 mg KOH / g or less, and the oxyethylidene unit at the molecular end of the first polyol comprises 10% by mass or more and 60% by mass relative to the total amount of oxyalkylene units of the second polyol; the second polyol has an average number of functional groups of 1.5 or more and 4.5 or less, the second polyol has a hydroxyl value of 20 mg KOH / g or more and 70 mg KOH / g relative to the total amount of oxyalkylene units of the second polyol; and the third polyol comprises 10% by mass or more and 60% by mass relative to the total amount of oxyalkylene units of the second polyol. The oxyethylidene unit of the alcohol is less than 10% by mass, the average number of functional groups of the aforementioned third polyol is 1.5 to 4.5, the hydroxyl value of the aforementioned third polyol is 120 mg KOH / g to 300 mg KOH / g, the oxyethylidene unit content of the aforementioned third polyol is 10% by mass or more relative to the total amount of the aforementioned alkylene units, the content of the aforementioned first polyol is 12% by mass or more to 28% by mass relative to the total amount of the aforementioned first polyol, the aforementioned second polyol and the aforementioned third polyol, the content of the aforementioned first polyol is 12% by mass or more to 28% by mass relative to the total amount of the aforementioned first polyol, the aforementioned second polyol is 12% by mass or more to 28% by mass, and the content of the aforementioned third polyol is 52% by mass or more to 68% by mass.

[0013] The present invention [2] includes a polyol composition containing a first polyol, a second polyol, and a third polyol, wherein the first polyol has an average number of functional groups of 1.5 to 4.5, a hydroxyl value of 20 mg KOH / g to 60 mg KOH / g, and, relative to the total amount of alkylene units of the first polyol, the content of ethylene units of the first polyol is 10% to 80% by mass; the second polyol has an average number of functional groups of 1.5 to 4.5, a hydroxyl value of 20 mg KOH / g to 70 mg KOH / g, and, relative to the total amount of alkylene units of the second polyol, the content of ethylene units of the second polyol is less than 10% by mass; and the third polyol has an average number of functional groups of 1.5 to 4.5. The hydroxyl value of the aforementioned third polyol is 120 mg KOH / g or more and 300 mg KOH / g or less. The content of the oxyethylidene unit of the aforementioned third polyol is 10% by mass or more relative to the total amount of the alkylene units of the aforementioned third polyol. The content of the aforementioned first polyol is 12% by mass or more and 28% by mass or less relative to the total amount of the aforementioned first, second, and third polyols. The content of the aforementioned second polyol is 12% by mass or more and 28% by mass or less. The content of the aforementioned third polyol is 52% by mass or more and 68% by mass or less. The hydroxyl value of the aforementioned first polyol is set as OHv1 (mg KOH / g). The content of the oxyethylidene unit at the molecule end of the aforementioned first polyol relative to the total amount of the alkylene units of the aforementioned first polyol is set as R. EO1 (mass%), the hydroxyl value of the aforementioned second polyol is set as OHv2 (mgKOH / g), and the content ratio of the aforementioned second polyol's oxyethylidene units relative to the total amount of oxyalkylene units of the aforementioned second polyol is set as R. EO2 (mass%), the hydroxyl value of the aforementioned third polyol is set as OHv3 (mgKOH / g), and the content ratio of the aforementioned third polyol's oxyethylidene units relative to the total amount of oxyalkylene units of the aforementioned third polyol is set as R. EO3 When (mass%), the distance X (mgKOH / g + mass%) expressed by the following formula (2) is less than 80.

[0014] Distance X = ({OHv2 - [(OHv1 + OHv3) / 2]} 2 +{R EO2 -[(R) EO1 +R EO3 ) / 2]} 2 ) 1 / 2 ···(2) The present invention [3] includes the polyol composition described in [1] or [2] above, wherein the content of the oxyethylidene unit at the molecular end of the first polyol is 12% by mass or more and 30% by mass or less, relative to the total amount of the oxyalkylene units of the first polyol.

[0015] The present invention [4] includes any one of the above [1] to [3] polyol compositions, wherein the first polyol is a block copolymer of propylene oxide and ethylene oxide.

[0016] The present invention [5] includes any one of the above [1] to [4] polyol compositions, wherein the number average molecular weight of the first polyol is 4100 or more.

[0017] The present invention [6] includes the polyol composition described in any one of [1] to [5] above, wherein, relative to the total amount of the first polyol, the second polyol and the third polyol, the content of the first polyol is 16% by mass or more and 24% by mass or less, the content of the second polyol is 16% by mass or more and 24% by mass or less, and the content of the third polyol is 55% by mass or more and 65% by mass or less.

[0018] The present invention [7] includes any of the polyol compositions described in any one of [1] to [6] above, which are used in the manufacture of polyurethane foams.

[0019] The present invention [8] includes a polyol composition having an average number of functional groups of 1.5 or more and 4.5 or less, a hydroxyl value of 80 mg KOH / g or more and 120 mg KOH / g or less, and an oxyethylidene unit content of 15.0% by mass or more and 17.3% by mass relative to the total amount of oxyalkylene units in the aforementioned polyol composition.

[0020] The present invention [9] includes a urethane foam composition, which is a urethane foam composition containing a polyol component and a polyisocyanate component, wherein the aforementioned polyol component contains any one of the polyol compositions described in [1] to [8].

[0021] The present invention

[10] includes a polyurethane foam, which is a polyurethane foam obtained by reacting the urethane foam composition described above [9], wherein the urethane foam composition contains a polyol component and a polyisocyanate component, wherein the polyol component contains the polyol composition described above [9], wherein the polyurethane foam has at least one glass transition temperature in a temperature range of -70°C to -30°C and a temperature range of 0°C to 60°C, wherein when the glass transition temperature is expressed as the peak value of tanδ measured by dynamic viscoelasticity determination at a vibration frequency of 10 Hz, the peak value of tanδ in the range of -70°C to -30°C is 0.10 or less, the peak value of tanδ in the range of 0°C to 60°C is 0.30 or more, and the value of tanδ at -25°C is 0.095 or more.

[0022] The present invention

[11] includes the polyurethane foam described in

[10] above, wherein the peak value of tanδ at -70℃ to -30℃ is below 0.07, and the value of tanδ at -25℃ is above 0.10.

[0023] The present invention

[12] includes the polyurethane foam described in any one of

[10] or

[11] above, wherein the aforementioned polyisocyanate component contains at least one polyisocyanate compound selected from the group consisting of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate.

[0024] The present invention

[13] includes any one of the polyurethane foams described in

[10] to

[12] above, wherein the isocyanate index ([isocyanate group in the urethane foam composition / active hydrogen group in the urethane foam composition] × 100) of the aforementioned urethane foam composition is 50 or more and 200 or less.

[0025] The present invention

[14] includes a molded body comprising any one of the polyurethane foams described in any one of

[10] to

[13] above.

[0026] The present invention

[15] includes the molded body described above

[14] , which is a cushion or mattress.

[0027] Invention Effects According to the polyol composition and urethane foam composition of the present invention, it is possible to manufacture polyurethane foam with excellent low resilience and the ability to suppress hardness changes in lower temperature regions.

[0028] The polyurethane foam and molded body of the present invention are obtained using the above-mentioned polyol composition, and therefore have excellent low resilience and can suppress hardness changes in lower temperature regions. Attached Figure Description

[0029] [ Figure 1 ] Figure 1 The temperature curves with tanδ obtained by dynamic viscoelasticity test of the polyurethane foams of Example 2, Comparative Example 10 and Comparative Example 11 are shown.

[0030] [ Figure 2 ] Figure 2 Temperature curves showing the energy storage modulus (E') of the polyurethane foams of Examples 2, 10, and 11, measured by dynamic viscoelasticity tests. Detailed Implementation

[0031] Hereinafter, an example of a preferred embodiment of the present invention is disclosed and described in detail. The following description and examples are illustrative of the embodiment and do not limit the scope of the embodiment. In the present invention, a combination of two or more preferred embodiments is a more preferred embodiment. In the present invention, the numerical range indicated by "~" refers to the range including the values ​​recorded before and after "~" as both the lower and upper limits. In the numerical ranges recorded in stages in the present invention, the upper or lower limit recorded in a certain numerical range can be replaced by the upper or lower limit of other numerical ranges recorded in stages. Furthermore, in the numerical ranges recorded in the present invention, the upper or lower limit recorded in a certain numerical range can also be replaced by the values ​​shown in the examples. In the present invention, regarding the amount of each component in the composition, when multiple substances belonging to each component are present in the composition, unless otherwise specified, it refers to the total amount of the multiple substances present in the composition. In the present invention, "mass%" and "weight%" are synonymous, and "parts by mass" and "parts by weight" are synonymous. In the present invention, unless otherwise specified, the "%" indicating the amount of a component is based on mass. In the description of groups (atomic groups) in this specification, the terms "unsubstituted" and "unsubstituted" include not only cases without substituents but also cases with substituents. In this invention, the term "layer" includes not only cases formed entirely within the region where the layer is observed, but also cases formed only in a portion of the region. In this invention, the term "process" includes not only independent processes but also processes that, when not clearly distinguishable from others, are included as long as the purpose of the process is achieved.

[0032] 1. Polyol composition 1) First Implementation Method The first embodiment of the present invention will now be described in detail.

[0033] In the first embodiment, the polyol composition contains a first polyol, a second polyol, and a third polyol. Preferably, the polyol composition consists of a first polyol, a second polyol, and a third polyol.

[0034] (1) First polyol The first polyol is a polyol having the average number of functional groups described later, the number of hydroxyl groups described later, and the oxyethylidene content described later.

[0035] [Structure of the first polyol] Examples of high molecular weight polyols can be cited as the first polyol. High molecular weight polyols are organic compounds having two or more hydroxyl groups in their molecule and a high molecular weight. The number-average molecular weight of high molecular weight polyols is, for example, 400 or more, preferably 500 or more. Alternatively, the number-average molecular weight of high molecular weight polyols is, for example, 5000 or less. It should be noted that the number-average molecular weight can be determined using known gel permeation chromatography in the form of molecular weight converted to polyethylene glycol (hereinafter the same).

[0036] More specifically, examples of high molecular weight polyols include those having polyoxyalkylene units. Examples of high molecular weight polyols having polyoxyalkylene units include polyoxyalkylene polyols, polyoxyalkylene polyester polyols, and polyoxyalkylene polyols containing vinyl polymers.

[0037] Examples of polyoxyalkylene polyols include addition polymers of epoxides. Examples of initiators in addition polymerization include low molecular weight polyols and low molecular weight polyamines.

[0038] Low molecular weight polyols are compounds having two or more hydroxyl groups and a molecular weight of less than 400. Examples of low molecular weight polyols include diols, triols, tetraols, pentols, hexaols, heptols, and octols. Examples of diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentanediol, 3-methyl-1,5-pentanediol, 2,2,2-trimethylpentanediol, 3,3-dihydroxymethylheptane, alkane (C7~20) diols, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, hydrogenated bisphenol A, 1,4-dihydroxy-2-butene, 2,6-dimethyl-1-octene-3,8-diol, bisphenol A, diethylene glycol, triethylene glycol, and dipropylene glycol. Examples of triols include glycerol, trimethylolpropane, and triisopropanolamine. Examples of tetrahydric alcohols include tetramethylol(hydroxymethyl)methane (pentaerythritol) and diglycerides. Examples of pentahydric alcohols include xylitol. Examples of hexahydric alcohols include sorbitol, mannitol, allitol, idotitol, eurythritol, atroitol, inositol, and dipentaerythritol. Examples of heptanoyl alcohols include avocadool. Examples of octanoyl alcohols include sucrose. They can be used alone or in combination of two or more.

[0039] Low molecular weight polyamines are compounds having two or more amino groups and a molecular weight less than 400. Examples of low molecular weight polyamines include low molecular weight diamines, low molecular weight triamines, and low molecular weight polyamines having four or more amino groups. Examples of low molecular weight diamines include ethylenediamine, 1,3-propanediamine, 1,3-butanediamine, 1,4-butanediamine, 1,6-hexanediamine, 1,4-cyclohexanediamine, 3-aminomethyl-3,5,5-trimethylcyclohexylamine (isophorone diamine), 4,4'-dicyclohexylmethanediamine, 2,5-bis(aminomethyl)bicyclo[2.2.1]heptane, 2,6-bis(aminomethyl)bicyclo[2.2.1]heptane, 1,3-bis(aminomethyl)cyclohexane, hydrazine, and toluenediamine. Examples of low molecular weight triamines include diethylenetriamine. Examples of low molecular weight polyamines containing four or more amino groups include triethylenetetramine and tetraethylenepentamine. They can be used alone or in combination of two or more.

[0040] Examples of epoxides include those with 2 to 12 carbon atoms. More specifically, examples of epoxides include ethylene oxide, propylene oxide, 1,2-epoxybutane, 1,3-epoxybutane, 1,4-epoxybutane, 2,3-epoxybutane, styrene oxide, epicyclohexane oxide, epichlorohydrin, epibromopropane, methyl glycidyl ether, allyl glycidyl ether, and phenyl glycidyl ether. These can be used alone or in combination of two or more. Preferably, epoxides with 2 to 8 carbon atoms are included; more preferably, epoxides with 2 to 4 carbon atoms are included; and even more preferably, epoxides with 2 to 3 carbon atoms are included. More specifically, ethylene oxide, propylene oxide, 1,2-epoxybutane, and styrene oxide are preferred examples of epoxides; more preferably, ethylene oxide, propylene oxide, and 1,2-epoxybutane are preferred examples; and even more preferably, ethylene oxide and propylene oxide are preferred examples. Particularly preferred are the combined use of ethylene oxide and propylene oxide.

[0041] It should be noted that there are no particular restrictions on the method for adding alkyl epoxides to initiators (low molecular weight polyols and / or low molecular weight polyamines), and known methods can be used.

[0042] The addition polymer of epoxides is a polyol having an oxoalkylene unit as a repeating unit. The oxoalkylene unit can be determined according to the type of epoxide, as described above. Preferably, oxoethylene, oxopropylene, 1,2-oxobutylene, and phenyloxoethylene units are oxoethylene, oxopropylene, and 1,2-oxobutylene units are oxoethylene, oxopropylene, and 1,2-oxobutylene units are oxoethylene, and even more preferably, oxoethylene and oxopropylene units are oxopropylene. Particularly preferred is the combination of oxoethylene and oxopropylene units.

[0043] Examples of addition polymers of epoxides include homopolymers of one epoxide and copolymers of two or more epoxides, with copolymers of two or more epoxides being more preferred. Examples of copolymers include random copolymers and block copolymers, with block copolymers being more preferred.

[0044] The polyoxyalkylene polyol is preferably a copolymer containing two or more epoxides, more preferably a copolymer of two or more epoxides, and even more preferably a copolymer of two epoxides.

[0045] Examples of polyoxyalkylene polyols include, more specifically, polyethylene glycol, polypropylene glycol, and copolymers of propylene oxide and ethylene oxide. Examples of propylene oxide-ethylene oxide copolymers include, for example, random copolymers of propylene oxide and ethylene oxide, and block copolymers of propylene oxide and ethylene oxide. These can be used alone or in combination of two or more. Copolymers of propylene oxide and ethylene oxide are preferred as polyoxyalkylene polyols, and block copolymers of propylene oxide and ethylene oxide are more preferred.

[0046] The propylene oxide-ethylene oxide block copolymer comprises at least one polyoxyethylene portion (EO portion) and at least one polyoxypropylene portion (PO portion). The polyoxyethylene portion (EO portion) is a portion having multiple oxyethylene units as repeating units. Similarly, the polyoxypropylene portion (PO portion) is a portion having multiple oxypropylene units as repeating units.

[0047] Examples of propylene oxide-ethylene oxide block copolymers include propylene oxide-ethylene oxide block copolymers with terminal oxyethylidene groups and propylene oxide-ethylene oxide block copolymers with terminal oxypropylene groups. Examples of propylene oxide-ethylene oxide block copolymers with terminal oxyethylidene groups include polypropylene polyols (-PO-EO groups) having polyoxyethylidene groups at the molecular ends; additionally, examples of block copolymers (-PO-EO-PO-EO groups) having alternating polyoxyethylidene groups and polyoxypropylene groups, and having oxyethylidene groups at the molecular ends. Examples of propylene oxide-ethylene oxide block copolymers with terminal oxypropylene groups include polyethylene polyols (terminated oxypropylene type, -EO-PO group) having polyoxypropylene groups at the molecular ends, and block copolymers having alternating polyoxyethylene and polyoxypropylene groups, with polyoxypropylene groups at the molecular ends (-PO-EO-PO group). These can be used alone or in combination of two or more. Propylene oxide-ethylene oxide block copolymers with terminal oxypropylene groups are preferred.

[0048] Examples of polyoxyalkylene polyester polyols include, for example, the polyether polyester polyols described in Japanese Patent Publication No. 48-10078, and more specifically, polyoxyalkylene polyester block copolymers.

[0049] Polyoxyalkylene polyester block copolymers can be obtained, for example, by block copolymerization of polyester chains with the aforementioned polyoxyalkylene polyols. More specifically, polyoxyalkylene polyester block copolymers can be obtained, for example, by reacting known polycarboxylic anhydrides and epoxides (cyclic ether compounds) with the aforementioned polyoxyalkylene polyols. Polyoxyalkylene polyester block copolymers have structural units, for example, those shown in general formula (1).

[0050] [Chemical Formula 1] (In the formula, R1 and R2 are each divalent hydrocarbon groups, and n represents the number greater than the average value of 1.) In general formula (1), the divalent hydrocarbon residue represented by R1 can be, for example, a residue of a polycarboxylic acid. In general formula (1), the divalent hydrocarbon residue represented by R2 can be, for example, a residue of a cyclic ether compound. In general formula (1), n ​​represents a number greater than the average value of 1, preferably greater than the average value of 1 and less than 20.

[0051] Polyoxyalkylene polyols containing vinyl polymers can be obtained, for example, by dispersive polymerization of vinyl monomers in the polyoxyalkylene polyols described above.

[0052] Examples of vinyl monomers include alkyl (meth)acrylates, styrene, (meth)acrylamide, vinyl cyanide, and vinylidene cyanide. They can be used alone or in combination of two or more. Styrene and vinyl cyanide are preferred vinyl monomers. A combination of styrene and vinyl cyanide is more preferred.

[0053] There are no particular limitations on the polymerization method of vinyl monomers. For example, vinyl monomers and known free radical polymerization initiators can be incorporated into the aforementioned polyoxyalkylene polyol. Then, the vinyl monomers are subjected to free radical polymerization in the polyoxyalkylene polyol. Examples of free radical polymerization initiators include persulfates, organic peroxides, and azo compounds. Furthermore, additives can be added as needed during the above polymerization. Examples of additives include dispersing stabilizers and chain transfer agents.

[0054] The polymerization process described above yields a polymer of vinyl monomers (hereinafter referred to as the vinyl polymer). The vinyl polymer is dispersed in a polyoxyalkylene polyol in the form of polymer microparticles. That is, the polymerization process described above yields a polyoxyalkylene polyol containing the vinyl polymer. It should be noted that at least a portion of the vinyl monomers in the polymer microparticles can be grafted with the polyoxyalkylene polyol.

[0055] The proportion of vinyl polymer in the polyoxyalkylene polyol containing vinyl polymer is, for example, 2% by mass or more, preferably 5% by mass or more. Furthermore, the proportion of vinyl polymer in the polyoxyalkylene polyol containing vinyl polymer is, for example, 50% by mass or less, preferably 45% by mass or less.

[0056] From the viewpoint of low resilience and suppression of hardness changes, polyoxyalkylene polyols are preferred as high molecular weight polyols, copolymers of propylene oxide and ethylene oxide are more preferred, block copolymers of propylene oxide and ethylene oxide are even more preferred, and block copolymers of propylene oxide and ethylene oxide with terminal oxyethylidene form are particularly preferred.

[0057] That is, the first polyol is preferably a polyoxyalkylene polyol, more preferably a copolymer of propylene oxide and ethylene oxide, even more preferably a block copolymer of propylene oxide and ethylene oxide, and especially preferably a block copolymer of propylene oxide and ethylene oxide with terminal oxyethylidene.

[0058] [Physical properties of the first polyol] The first polyol has a specified average number of functional groups, a specified hydroxyl value, and a specified oxyethylidene content.

[0059] The average number of functional groups (average number of hydroxyl groups) of the first polyol is 1.5 or more, preferably 1.8 or more, more preferably 2.0 or more, and even more preferably 2.5 or more. Furthermore, the average number of functional groups (average number of hydroxyl groups) of the first polyol is 4.5 or less, preferably 4.0 or less, and even more preferably 3.5 or less. That is, the average number of functional groups (average number of hydroxyl groups) of the first polyol is 1.5 or more and 4.5 or less, preferably 1.8 or more and 4.0 or less, more preferably 2.0 or more and 3.5 or less, and even more preferably 2.5 or more and 3.5 or less. If the average number of functional groups (average number of hydroxyl groups) of the first polyol is within the above range, a polyurethane foam (described later) with excellent low resilience and the ability to suppress hardness changes in a lower temperature region can be obtained. In particular, if the average number of functional groups (average number of hydroxyl groups) of the first polyol is the lower limit or above, excellent compression set can be obtained. Furthermore, if the average number of functional groups (average number of hydroxyl groups) of the first polyol is below the aforementioned upper limit, excellent elongation and excellent hardness can be achieved simultaneously, resulting in excellent tensile properties. It should be noted that the average number of functional groups (average number of hydroxyl groups) can be calculated from the type of raw material and the charge formulation of the polyol (the same applies below).

[0060] The hydroxyl value of the first polyol is 20 mg KOH / g or more, preferably 23 mg KOH / g or more, more preferably 25 mg KOH / g or more, and even more preferably 30 mg KOH / g or more. Furthermore, the hydroxyl value of the first polyol is 50 mg KOH / g or less, preferably 45 mg KOH / g or less, and even more preferably 40 mg KOH / g or less. That is, the hydroxyl value of the first polyol is 20 mg KOH / g or more and 50 mg KOH / g or less, preferably 23 mg KOH / g or more and 45 mg KOH / g or less, more preferably 25 mg KOH / g or more and 45 mg KOH / g or less, and even more preferably 30 mg KOH / g or more and 40 mg KOH / g or less. If the hydroxyl value of the first polyol is within the above range, a polyurethane foam with excellent low resilience and the ability to suppress hardness changes in a lower temperature region can be obtained (described later). It should be noted that the hydroxyl value can be determined according to the acetyl value method described in JISK-1557-1 (2007) (the same applies below).

[0061] The content of oxyethylidene units relative to the total amount of oxyalkylene units in the first polyol (oxyethylidene content) is, for example, 10% by mass or more, preferably 11% by mass or more, more preferably 12% by mass or more, and even more preferably 13% by mass or more. Furthermore, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the first polyol (oxyethylidene content) is, for example, 60% by mass or less, preferably 50% by mass or less, more preferably 30% by mass or less, and even more preferably 25% by mass or less. That is, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the first polyol (oxyethylidene content) is preferably 10% by mass or more and 60% by mass or less, preferably 11% by mass or more and 50% by mass or less, more preferably 12% by mass or more and 30% by mass or less, and even more preferably 13% by mass or more and 25% by mass or less.

[0062] Especially when the first polyol is a propylene oxide-ethylene oxide block copolymer with terminal oxyethylidene, the content of terminal oxyethylidene units (oxyethylidene content) of the first polyol is 10% by mass or more, preferably 11% by mass or more, more preferably 12% by mass or more, and even more preferably 13% by mass or more, relative to the total amount of oxyalkylene units in the first polyol. Furthermore, the content of terminal oxyethylidene units (oxyethylidene content) of the first polyol is 60% by mass or less, preferably 50% by mass or less, more preferably 30% by mass or less, and even more preferably 25% by mass or less, relative to the total amount of oxyalkylene units in the first polyol. That is, the content of terminal oxyethylidene units (oxyethylidene content) of the first polyol is 10% by mass or more and 60% by mass or less, preferably 11% by mass or more and 50% by mass or less, more preferably 12% by mass or more and 30% by mass or less, and even more preferably 13% by mass or more and 25% by mass or less. If the proportion of oxyethylidene units at the molecular ends of the first polyol is within the above range, a polyurethane foam with excellent low resilience and the ability to suppress hardness changes in a lower temperature range can be obtained (described later). It should be noted that the oxyethylidene content can be calculated from the type of raw material of the polyol and the filling formulation. Furthermore, the oxyethylidene content can be determined by… 1 It is determined by H-NMR measurement (the same applies below).

[0063] The number average molecular weight (converted to polyethylene glycol) of the first polyol is, for example, 400 or more, preferably 1000 or more, more preferably 2000 or more, even more preferably 3000 or more, even more preferably greater than 4000, even more preferably 4100 or more, and particularly preferably 4500 or more. Furthermore, the number average molecular weight (converted to polyethylene glycol) of the first polyol is, for example, 15000 or less, preferably 10000 or less, more preferably 9000 or less, even more preferably 7000 or less, even more preferably 6000 or less, even more preferably 5800 or less, and particularly preferably 5500 or less. Therefore, the number-average molecular weight of the first polyol is, for example, 400 to 15,000, preferably 1,000 to 15,000, more preferably 2,000 to 9,000, even more preferably 3,000 to 7,000, even more preferably greater than 4,000 and less than 6,000, even more preferably 4,100 to 5,800, and particularly preferably 4,500 to 5,500. It should be noted that the number-average molecular weight can be determined by gel permeation chromatography (GPC) analysis (the same applies below).

[0064] [Percentage of first polyol] The content of the first polyol is 12% by mass or more, preferably 14% by mass or more, more preferably 16% by mass or more, and even more preferably 18% by mass or more, relative to the total amount of the first, second, and third polyols. Furthermore, the content of the first polyol is 28% by mass or less, preferably 26% by mass or less, more preferably 24% by mass or less, and even more preferably 22% by mass or less, relative to the total amount of the first, second, and third polyols. That is, the content of the first polyol is 12% by mass or more and 28% by mass or less, preferably 14% by mass or more and 26% by mass or less, more preferably 16% by mass or more and 24% by mass or less, and even more preferably 18% by mass or more and 22% by mass or less, relative to the total amount of the first, second, and third polyols. If the content of the first polyol is within the above range, the variation in tanδ can be smaller in the temperature region (described later) where the negative peak (valley) of tanδ of the polyurethane foam (described later). More specifically, if the content ratio of the first polyol is within the above-mentioned range, the peak value of tanδ in the polyurethane foam (described later) at -70 to -30°C can be adjusted to 0.1 or less, and the tanδ value at -25°C can be adjusted to 0.095 or more. Therefore, a polyurethane foam (described later) with excellent low resilience and the ability to suppress hardness changes in lower temperature regions can be obtained. In particular, if the content ratio of the first polyol is within the above-mentioned range, a polyurethane foam with excellent compression set can be obtained.

[0065] (2) Second polyol The second polyol is a polyol having the average number of functional groups described later, the number of hydroxyl groups described later, and the oxyethylidene content described later.

[0066] [Structure of the second polyol] Examples of second polyols include, for example, the high molecular weight polyols described above. More specifically, examples of second polyols include, for example, the polyoxyalkylene polyols described above, the polyoxyalkylene polyester polyols described above, and the polyoxyalkylene polyols containing vinyl polymers described above.

[0067] From the viewpoint of low resilience and suppression of hardness changes, polyoxyalkylene polyols are preferred as high molecular weight polyols, polyoxypropylene polyols and copolymers of propylene oxide and ethylene oxide are more preferred, and polyoxypropylene polyols (containing 0% by mass) are even more preferred, as described below.

[0068] That is, the second polyol is preferably a polyoxyalkylene polyol, more preferably a polyoxypropylene polyol, and / or a copolymer of propylene oxide and ethylene oxide, and even more preferably a polyoxypropylene polyol (with an oxyethylene content of 0% by mass) as described later.

[0069] [Physical properties of the second polyol] The second polyol has a specified average number of functional groups, a specified hydroxyl value, and a specified oxyethylidene content.

[0070] The average number of functional groups (average number of hydroxyl groups) of the second polyol is 1.5 or more, preferably 1.8 or more, more preferably 2.0 or more, and even more preferably 2.5 or more. Furthermore, the average number of functional groups (average number of hydroxyl groups) of the second polyol is 4.5 or less, preferably 4.0 or less, and even more preferably 3.5 or less. That is, the average number of functional groups (average number of hydroxyl groups) of the second polyol is 1.5 or more and 4.5 or less, preferably 1.8 or more and 4.0 or less, more preferably 2.0 or more and 3.5 or less, and even more preferably 2.5 or more and 3.5 or less. If the average number of functional groups (average number of hydroxyl groups) of the second polyol is within the above range, a polyurethane foam (described later) exhibiting excellent low resilience and the ability to suppress hardness changes in lower temperature regions can be obtained. In particular, if the average number of functional groups (average number of hydroxyl groups) of the second polyol is at or above the above lower limit, excellent compression set can be obtained. In addition, if the average number of functional groups (average number of hydroxyl groups) of the second polyol is below the above upper limit, excellent elongation and excellent hardness can be achieved at the same time, resulting in excellent tensile properties.

[0071] The hydroxyl value of the second polyol is 20 mg KOH / g or more, preferably 23 mg KOH / g or more, more preferably 25 mg KOH / g or more, and even more preferably 30 mg KOH / g or more. Furthermore, the hydroxyl value of the second polyol is 70 mg KOH / g or less, preferably 60 mg KOH / g or less, and even more preferably 50 mg KOH / g or less. That is, the hydroxyl value of the second polyol is 20 mg KOH / g or more and 70 mg KOH / g or less, preferably 23 mg KOH / g or more and 60 mg KOH / g or less, more preferably 25 mg KOH / g or more and 50 mg KOH / g or less, and even more preferably 30 mg KOH / g or more and 50 mg KOH / g or less. If the hydroxyl value of the second polyol is within the above range, a polyurethane foam with excellent low resilience and the ability to suppress hardness changes in a lower temperature region can be obtained (described later).

[0072] The content of oxyethylidene units relative to the total amount of oxyalkylene units in the second polyol (oxyethylidene content) is less than 10% by mass, preferably less than 5% by mass, and more preferably less than 2% by mass. It should be noted that the content of oxyethylidene units relative to the total amount of oxyalkylene units in the second polyol (oxyethylidene content) is, for example, 0% by mass or more. That is, the second polyol may also not contain oxyethylidene units. Specifically, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the second polyol (oxyethylidene content) is 0% by mass or more and less than 10% by mass, preferably 0% by mass or more and less than 5% by mass, and more preferably 0% by mass or more and less than 2% by mass.

[0073] The second polyol is particularly preferred to be a polyoxypropylene polyol. It should be noted that the content ratio (oxyethylene content) of the oxyethylidene units relative to the total amount of oxyalkylene units in the polyoxypropylene polyol is 0 by mass.

[0074] The number average molecular weight (converted to polyethylene glycol) of the second polyol is, for example, 400 or more, preferably 1000 or more, more preferably 2000 or more, and even more preferably 3000 or more. Furthermore, the number average molecular weight (converted to polyethylene glycol) of the second polyol is, for example, 15000 or less, preferably 10000 or less, more preferably 9000 or less, and even more preferably 7000 or less.

[0075] The average number of functional groups, hydroxyl value, and number-average molecular weight of the second polyol can be similar to those of the first polyol.

[0076] For example, the difference between the average number of functional groups of the second polyol and the first polyol can be within ±0.5. Additionally, the difference between the hydroxyl value of the second polyol and the first polyol can be within ±5 mg KOH / g. Furthermore, the difference between the number-average molecular weight of the second polyol and the first polyol can be within ±1000.

[0077] When the average number of functional groups, hydroxyl value, and number-average molecular weight of the second polyol are similar to those of the first polyol, the second polyol and the first polyol can be distinguished by, for example, the content of oxyethylidene.

[0078] The difference between the oxyethylidene content of the second polyol and the oxyethylidene content of the first polyol is, for example, 1% by mass or more, preferably 3% by mass or more, more preferably 5% by mass or more, further preferably 10% by mass or more, and especially preferably 15% by mass or more. Furthermore, the difference between the oxyethylidene content of the second polyol and the oxyethylidene content of the first polyol is, for example, 60% by mass or less, preferably 50% by mass or less, more preferably 40% by mass or less, further preferably 30% by mass or less, and especially preferably 20% by mass or less. That is, the difference between the oxyethylidene content of the second polyol and the oxyethylidene content of the first polyol is, for example, 1% by mass or more and 60% by mass or less, preferably 3% by mass or more and 50% by mass or less, more preferably 5% by mass or more and 40% by mass or less, further preferably 10% by mass or more and 30% by mass or less, and especially preferably 15% by mass or more and 20% by mass or less.

[0079] [Percentage of second polyol] The content of the second polyol is 12% by mass or more, preferably 14% by mass or more, more preferably 16% by mass or more, and even more preferably 18% by mass or more, relative to the total amount of the first, second, and third polyols. Furthermore, the content of the second polyol is 28% by mass or less, preferably 26% by mass or less, more preferably 24% by mass or less, and even more preferably 22% by mass or less, relative to the total amount of the first, second, and third polyols. That is, the content of the second polyol is 12% by mass or more and 28% by mass or less, preferably 14% by mass or more and 26% by mass or less, more preferably 16% by mass or more and 24% by mass or less, and even more preferably 18% by mass or more and 22% by mass or less, relative to the total amount of the first, second, and third polyols. If the content of the second polyol is within the above range, the variation of tanδ in the temperature region (described later) where the negative peak (valley) of tanδ of the polyurethane foam (described later) is generated can be made smaller. More specifically, if the content ratio of the first polyol is within the above-mentioned range, the peak value of tanδ in the polyurethane foam (described later) at -70 to -30°C can be adjusted to 0.1 or less, and the tanδ value at -25°C can be adjusted to 0.095 or more. Therefore, a polyurethane foam (described later) with excellent low resilience and the ability to suppress hardness changes in lower temperature regions can be obtained. In particular, if the content ratio of the second polyol is within the above-mentioned range, a polyurethane foam with excellent compression set can be obtained.

[0080] Furthermore, relative to 100 parts by mass of the first polyol, the content of the second polyol is, for example, 10 parts by mass or more, preferably 30 parts by mass or more, more preferably 50 parts by mass or more, further preferably 70 parts by mass or more, and especially preferably 90 parts by mass or more. Additionally, relative to 100 parts by mass of the first polyol, the content of the second polyol is, for example, 500 parts by mass or less, preferably 400 parts by mass or less, more preferably 300 parts by mass or less, further preferably 200 parts by mass or less, and especially preferably 150 parts by mass or less. That is, relative to 100 parts by mass of the first polyol, the content of the second polyol is, for example, 10 parts by mass or more and 500 parts by mass or less, preferably 30 parts by mass or more and 400 parts by mass or less, more preferably 50 parts by mass or more and 300 parts by mass or less, further preferably 70 parts by mass or more and 200 parts by mass or less, and especially preferably 90 parts by mass or more and 150 parts by mass or less.

[0081] (2) Third polyol The third polyol is a polyol having the average number of functional groups described later, the number of hydroxyl groups described later, and the oxyethylidene content described later.

[0082] [Structure of the third polyol] Examples of third polyols include the high molecular weight polyols described above. More specifically, examples of third polyols include the polyoxyalkylene polyols described above, the polyoxyalkylene polyester polyols described above, and the polyoxyalkylene polyols containing vinyl polymers described above.

[0083] From the viewpoint of low resilience and suppression of hardness changes, polyoxyalkylene polyols are preferred as high molecular weight polyols, copolymers of propylene oxide and ethylene oxide are more preferred, block copolymers of propylene oxide and ethylene oxide are even more preferred, and block copolymers of propylene oxide and ethylene oxide with terminal oxyethylidene form are particularly preferred.

[0084] That is, the third polyol is preferably a polyoxyalkylene polyol, preferably a copolymer of propylene oxide and ethylene oxide, more preferably a block copolymer of propylene oxide and ethylene oxide, and especially preferably a block copolymer of propylene oxide and ethylene oxide with terminal oxyethylidene.

[0085] [Physical properties of the third polyol] The third polyol has a specified average number of functional groups, a specified hydroxyl value, and a specified oxyethylidene content.

[0086] The average number of functional groups (average number of hydroxyl groups) of the third polyol is 1.5 or more, preferably 1.8 or more, more preferably 2.0 or more, and even more preferably 2.5 or more. Furthermore, the average number of functional groups (average number of hydroxyl groups) of the third polyol is 4.5 or less, preferably 4.0 or less, and even more preferably 3.5 or less. That is, the average number of functional groups (average number of hydroxyl groups) of the third polyol is 1.5 or more and 4.5 or less, preferably 1.8 or more and 4.0 or less, more preferably 2.0 or more and 3.5 or less, and even more preferably 2.5 or more and 3.5 or less. If the average number of functional groups (average number of hydroxyl groups) of the third polyol is within the above range, a polyurethane foam (described later) with excellent low resilience and the ability to suppress hardness changes in a lower temperature region can be obtained. In particular, if the average number of functional groups (average number of hydroxyl groups) of the third polyol is the lower limit or above, excellent compression set can be obtained. In addition, if the average number of functional groups (average number of hydroxyl groups) of the third polyol is below the above upper limit, excellent elongation and excellent hardness can be achieved at the same time, resulting in excellent tensile properties.

[0087] The hydroxyl value of the third polyol is 120 mg KOH / g or more, preferably 125 mg KOH / g or more, and more preferably 130 mg KOH / g or more. Furthermore, the hydroxyl value of the third polyol is 300 mg KOH / g or less, preferably 250 mg KOH / g or less, more preferably 200 mg KOH / g or less, and even more preferably 160 mg KOH / g or less. That is, the hydroxyl value of the third polyol is 120 mg KOH / g or more and 300 mg KOH / g or less, preferably 125 mg KOH / g or more and 250 mg KOH / g or less, more preferably 130 mg KOH / g or more and 200 mg KOH / g or less, and even more preferably 130 mg KOH / g or more and 160 mg KOH / g or less. If the hydroxyl value of the third polyol is within the above range, a polyurethane foam with excellent low resilience and the ability to suppress hardness changes in a lower temperature region can be obtained (described later).

[0088] The content of oxyethylidene units relative to the total amount of oxyalkylene units in the third polyol (oxyethylidene content) is 10% by mass or more, preferably 15% by mass or more, more preferably 18% by mass or more, and even more preferably 20% by mass or more. Furthermore, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the third polyol (oxyethylidene content) is, for example, 40% by mass or less. That is, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the third polyol (oxyethylidene content) is 10% by mass or more and 40% by mass or less, preferably 15% by mass or more and 40% by mass or less, more preferably 18% by mass or more and 40% by mass or less, and even more preferably 20% by mass or more and 40% by mass or less.

[0089] Especially when the third polyol is a propylene oxide-ethylene oxide block copolymer with terminal oxyethylidene units, the content of terminal oxyethylidene units (oxyethylidene content) of the third polyol is, for example, 1% by mass or more, preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, relative to the total amount of oxyalkylene units in the third polyol. Furthermore, the content of terminal oxyethylidene units (oxyethylidene content) of the third polyol is, for example, 40% by mass or less, relative to the total amount of oxyalkylene units in the third polyol. That is, the content of terminal oxyethylidene units (oxyethylidene content) of the third polyol is, for example, 1% by mass or more and 40% by mass or less, preferably 5% by mass or more and 40% by mass or less, more preferably 10% by mass or more and 40% by mass or less, and even more preferably 15% by mass or more and 40% by mass or less, relative to the total amount of oxyalkylene units in the third polyol. If the content of the oxyethylidene unit at the molecular end of the third polyol is within the above range, a polyurethane foam with excellent low resilience and the ability to suppress hardness changes in a lower temperature region can be obtained (described later).

[0090] The number average molecular weight (converted to polyethylene glycol) of the third polyol is, for example, 400 or more, preferably 600 or more, more preferably 800 or more, and even more preferably 1000 or more. Furthermore, the number average molecular weight (converted to polyethylene glycol) of the third polyol is, for example, 5000 or less, preferably 3000 or less, more preferably 2000 or less, and even more preferably 1500 or less.

[0091] The average number of functional groups and the content of oxyethylidene in the third polyol can be the same as those in the first polyol.

[0092] For example, the difference between the average number of functional groups of the third polyol and the first polyol can be within ±0.5. Additionally, for example, the difference between the oxyethylidene content of the third polyol and the oxyethylidene content of the first polyol can be within ±10% by mass.

[0093] When the average number of functional groups and the content of oxyethylidene in the third polyol are to the same extent as those in the first polyol, the third polyol and the first polyol can be distinguished by, for example, hydroxyl value and number-average molecular weight.

[0094] The difference between the hydroxyl value of the third polyol and the hydroxyl value of the first polyol is, for example, 70 mg KOH / g or more, preferably 90 mg KOH / g or more, more preferably 100 mg KOH / g or more, and even more preferably 110 mg KOH / g or more. Furthermore, the difference between the hydroxyl value of the third polyol and the hydroxyl value of the first polyol is, for example, 280 mg KOH / g or less, preferably 200 mg KOH / g or less, more preferably 180 mg KOH / g or less, and even more preferably 150 mg KOH / g or less. That is, the difference between the hydroxyl value of the third polyol and the hydroxyl value of the first polyol is, for example, 70 mg KOH / g or more and 280 mg KOH / g or less, preferably 90 mg KOH / g or more and 200 mg KOH / g or less, more preferably 100 mg KOH / g or more and 180 mg KOH / g or less, and even more preferably 110 mg KOH / g or more and 150 mg KOH / g or less.

[0095] The difference between the number-average molecular weight of the third polyol and that of the first polyol is, for example, 500 or more, preferably 1000 or more, more preferably 2000 or more, and even more preferably 3000 or more. Furthermore, the difference between the number-average molecular weight of the third polyol and that of the first polyol is, for example, 14000 or less, preferably 10000 or less, more preferably 8000 or less, and even more preferably 5000 or less.

[0096] [Proportion of the third polyol] The content of the third polyol relative to the total amount of the first, second, and third polyols is 52% by mass or more, preferably 54% by mass or more, more preferably 55% by mass or more, even more preferably 56% by mass or more, and particularly preferably 58% by mass or more. Furthermore, the content of the third polyol relative to the total amount of the first, second, and third polyols is 68% by mass or less, preferably 65% ​​by mass or less, more preferably 63% by mass or less, and even more preferably 61% by mass or less. That is, the content of the third polyol relative to the total amount of the first, second, and third polyols is 52% by mass or more and 68% by mass or less, preferably 54% by mass or more and 65% by mass or less, more preferably 55% by mass or more and 63% by mass or less, even more preferably 56% by mass or more and 63% by mass or less, and particularly preferably 58% by mass or more and 61% by mass or less. If the content of the third polyol is within the above-mentioned range, the variation of tanδ can be minimized in the temperature region (described later) where the negative peak (valley) of tanδ of the polyurethane foam (described later) is generated. More specifically, if the content of the first polyol is within the above-mentioned range, the peak value of tanδ of the polyurethane foam (described later) in the range of -70 to -30°C can be adjusted to 0.1 or less, and the tanδ value at -25°C can be adjusted to 0.095 or more. Therefore, a polyurethane foam (described later) with excellent low resilience and the ability to suppress hardness changes in lower temperature regions can be obtained.

[0097] Furthermore, relative to 100 parts by mass of the first polyol, the content of the third polyol is, for example, 50 parts by mass or more, preferably 100 parts by mass or more, more preferably 200 parts by mass or more, even more preferably 250 parts by mass or more, and particularly preferably 280 parts by mass or more. Additionally, relative to 100 parts by mass of the first polyol, the content of the third polyol is, for example, 1000 parts by mass or less, preferably 800 parts by mass or less, more preferably 600 parts by mass or less, even more preferably 500 parts by mass or less, and particularly preferably 350 parts by mass or less. That is, relative to 100 parts by mass of the first polyol, the content of the third polyol is, for example, 50 parts by mass or more but less than 1000 parts by mass, preferably 100 parts by mass or more but less than 800 parts by mass, more preferably 200 parts by mass or more but less than 600 parts by mass, even more preferably 250 parts by mass or more but less than 500 parts by mass, and particularly preferably 280 parts by mass or more but less than 350 parts by mass.

[0098] (4) Other polyols The polyol composition may include other polyols as needed. Other polyols are polyols other than the first, second, and third polyols. Examples of other polyols include, for example, low molecular weight polyols and high molecular weight polyols (other than the first, second, and third polyols).

[0099] Examples of low molecular weight polyols include the aforementioned low molecular weight polyols, and more specifically, the aforementioned diols, triols, tetraols, pentols, hexaols, heptaols, and octaols. They can be used alone or in combination of two or more.

[0100] Examples of high molecular weight polyols (excluding the first, second, and third polyols) include those that do not have polyoxyalkylene units. Examples of high molecular weight polyols that do not have polyoxyalkylene units include polyester polyols, polycarbonate polyols, polyurethane polyols, epoxy polyols, vegetable oil polyols, polyolefin polyols, and acrylic polyols. There are no particular limitations on high molecular weight polyols; they can be manufactured using known methods. They can be used alone or in combination of two or more.

[0101] Other polyols may be used alone or in combination of two or more. It should be noted that, from the viewpoint of obtaining a polyurethane foam (described later) with excellent low resilience and the ability to suppress hardness changes in lower temperature regions, other polyols preferably do not contain high molecular weight polyols with polyoxyalkylene units (other than the first polyol, the second polyol and the third polyol).

[0102] Other polyols may be pre-mixed with the first polyol, the second polyol, or the third polyol. Alternatively, other polyols may be incorporated into the mixture of the first, second, and third polyols. Furthermore, other polyols may be added separately to the mixture of the first, second, and third polyols.

[0103] The proportion of other polyols can be suitably set within a range that does not impede the excellent effects of the present invention. For example, the proportion of other polyols relative to the total amount of the polyol composition is, for example, 30% by mass or less, preferably 20% by mass or less, more preferably 10% by mass or less, and particularly preferably 0% by mass. That is, the polyol composition preferably does not contain other polyols.

[0104] (5) Preparation of polyol compositions There are no particular limitations on the method for manufacturing the polyol composition. For example, firstly, the first polyol, the second polyol, and the third polyol described above are prepared in the aforementioned proportions. Additionally, other polyols may be prepared as needed. Then, the first polyol, the second polyol, the third polyol, and any other polyols prepared as needed are mixed using a known method. Thus, the polyol composition is obtained.

[0105] The average number of functional groups (average number of hydroxyl groups) of the polyol composition is, for example, 1.5 or more, preferably 1.8 or more, more preferably 2.0 or more, further preferably 2.3 or more, and especially preferably 2.8 or more. Furthermore, the average number of functional groups (average number of hydroxyl groups) of the polyol composition is, for example, 4.5 or less, preferably 4.2 or less, more preferably 4.0 or less, further preferably 3.7 or less, and especially preferably 3.3 or less. That is, the average number of functional groups (average number of hydroxyl groups) of the polyol composition is, for example, 1.5 or more and 4.5 or less, preferably 1.8 or more and 4.2 or less, more preferably 2.0 or more and 4.0 or less, further preferably 2.3 or more and 3.7 or less, and especially preferably 2.8 or more and 3.3 or less. If the average number of functional groups (average number of hydroxyl groups) of the polyol composition is within the above range, a polyurethane foam (described later) with excellent low resilience and the ability to suppress hardness changes in lower temperature regions can be obtained. It should be noted that the average number of functional groups in a polyol composition is a mol-based weighted average of the average number of functional groups of each polyol contained in the composition. The mol-based weighted average of the average number of functional groups can be calculated using known methods based on the molar percentage (mol%) of each polyol.

[0106] The hydroxyl value of the polyol composition is, for example, 80 mg KOH / g or more, preferably 85 mg KOH / g or more, more preferably 90 mg KOH / g or more, even more preferably 95 mg KOH / g or more, and particularly preferably 98 mg KOH / g or more. Furthermore, the hydroxyl value of the polyol composition is, for example, 120 mg KOH / g or less, preferably 115 mg KOH / g or less, more preferably 110 mg KOH / g or less, even more preferably 105 mg KOH / g or less, and particularly preferably 102 mg KOH / g or less. That is, the hydroxyl value of the polyol composition is, for example, 80 mg KOH / g or more and 120 mg KOH / g or less, preferably 85 mg KOH / g or more and 115 mg KOH / g or less, more preferably 90 mg KOH / g or more and 110 mg KOH / g or less, even more preferably 95 mg KOH / g or more and 105 mg KOH / g or less, and particularly preferably 98 mg KOH / g or more and 102 mg KOH / g or less. If the hydroxyl value of the polyol composition is within the above-mentioned range, a polyurethane foam with excellent low resilience and the ability to suppress hardness changes in a lower temperature range can be obtained (described later). It should be noted that the hydroxyl value of the polyol composition is a weighted average of the hydroxyl values ​​of the individual polyols contained in the composition, based on a mass basis. The weighted average of the hydroxyl values ​​based on a mass basis can be calculated using known methods based on the mass ratio (mass%) of each polyol.

[0107] The content of oxyethylidene units relative to the total amount of oxyalkylene units in the polyol composition (oxyethylidene content) is, for example, 15.0% by mass or more, preferably 15.1% by mass or more, and more preferably 15.2% by mass or more. Furthermore, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the polyol composition (oxyethylidene content) is, for example, 17.3% by mass or less, preferably 17.2% by mass or less, and more preferably 17.1% by mass or less. That is, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the polyol composition (oxyethylidene content) is, for example, 15.0% by mass or more and 17.3% by mass or less, preferably 15.1% by mass or more and 17.2% by mass or less, and more preferably 15.2% by mass or more and 17.1% by mass or less. It should be noted that the oxyethylidene content of the polyol composition is a weighted average of the oxyethylidene content of each polyol contained in the polyol composition, based on a mass basis. The weighted average of the mass basis of oxyethylidene content can be calculated using known methods based on the mass ratio (mass%) of each polyol.

[0108] (6) Effects Based on the above-described polyol composition, it is possible to manufacture polyurethane foams that have excellent low resilience and can suppress hardness changes in lower temperature regions (described later).

[0109] More specifically, the above-described polyol composition contains a second polyol and a third polyol in a specified ratio. The second and third polyols each have the above-described average number of functional groups, the above-described hydroxyl value, and the above-described oxyethylidene content.

[0110] Therefore, the polyurethane foam obtained using the above-described polyol composition (described later) preferably has at least two glass transition temperatures within a specified temperature range. As described later, the glass transition temperature is expressed as the peak value (positive peak) of tanδ measured by dynamic viscoelasticity determination in compression mode at a vibration frequency of 10 Hz. In other words, the polyurethane foam obtained using the above-described polyol composition (described later) preferably has at least two tanδ peak values ​​within a specified temperature range.

[0111] Such polyurethane foams (described later) exhibit excellent low resilience and excellent hardness due to the second and third polyols.

[0112] On the other hand, when only the second and third polyols are used without the first polyol, the value of tanδ sometimes decreases between at least two tanδ peaks (positive peaks), resulting in a negative tanδ peak (valley).

[0113] That is, in the lower temperature range (between the peaks (positive peaks) of tanδ), the variation of tanδ sometimes becomes larger. Under such circumstances, the variation of the hardness of the polyurethane foam also becomes correspondingly larger with the variation of tanδ.

[0114] That is, when using the second and third polyols without using the first polyol, sometimes the hardness change in the lower temperature range (between the peaks (positive peaks) of tanδ) cannot be suppressed, and sometimes the polyurethane foam becomes hard.

[0115] In contrast, the above-mentioned polyol composition contains, in addition to the second and third polyols, a first polyol in a specified proportion. The first polyol has the above-mentioned average number of functional groups, the above-mentioned hydroxyl value, and the above-mentioned oxyethylidene content.

[0116] The first polyol can suppress the phase transition of polyurethane foam corresponding to temperature changes, and therefore can suppress the decrease in the value of tanδ between the above-mentioned tanδ peaks (positive peaks).

[0117] That is, the first polyol can suppress the variation of tanδ in the lower temperature range (between the peaks (positive peaks) of tanδ). Therefore, the polyurethane foam (described later) obtained using the above-described polyol composition can suppress the variation of hardness in the lower temperature range.

[0118] That is, based on the above-mentioned polyol composition, it is possible to manufacture polyurethane foam with excellent low resilience and the ability to suppress hardness changes in lower temperature regions (described later).

[0119] Furthermore, if the first, second, and third polyols are used in combination in the aforementioned proportions, the polyurethane foam (described later) exhibits excellent healthy bubble properties. That is, during the manufacture of the polyurethane foam (described later), the gas generated inside the foam breaks down the cell membrane and is discharged from the polyurethane foam (described later). Therefore, the polyurethane foam (described later) possesses excellent air permeability even when not supplied to the interconnection process.

[0120] Therefore, the above-mentioned polyol composition is preferably used in the manufacture of polyurethane foam, and more preferably in the manufacture of low-resilience polyurethane foam.

[0121] In other words, the above-mentioned polyol composition is preferably a polyol composition for polyurethane foam, and more preferably a polyol composition for low-resilience polyurethane foam.

[0122] 2) Second Implementation Method The second embodiment of the present invention will now be described in detail. It should be noted that elements not described in detail below are the same as those in the first embodiment described above.

[0123] In the second embodiment, the polyol composition contains a first polyol, a second polyol, and a third polyol. Preferably, the polyol composition consists of a first polyol, a second polyol, and a third polyol.

[0124] (1) First polyol In the second embodiment, the first polyol can be exemplified by, for example, the high molecular weight polyol described above as part of the first embodiment. The first polyol is a polyol having the average number of functional groups described later, the number of hydroxyl groups described later, and the oxyethylidene content described later.

[0125] The average number of functional groups (average number of hydroxyl groups) of the first polyol is 1.5 or more, preferably 1.8 or more, more preferably 2.0 or more, and even more preferably 2.5 or more. Furthermore, the average number of functional groups (average number of hydroxyl groups) of the first polyol is 4.5 or less, preferably 4.0 or less, and even more preferably 3.5 or less. That is, the average number of functional groups (average number of hydroxyl groups) of the first polyol is 1.5 or more and 4.5 or less, preferably 1.8 or more and 4.0 or less, more preferably 2.0 or more and 3.5 or less, and even more preferably 2.5 or more and 3.5 or less.

[0126] The hydroxyl value of the first polyol is 20 mg KOH / g or more, preferably 23 mg KOH / g or more, more preferably 25 mg KOH / g or more, and even more preferably 30 mg KOH / g or more. Furthermore, the hydroxyl value of the first polyol is 60 mg KOH / g or less, preferably 58 mg KOH / g or less, and even more preferably 55 mg KOH / g or less. That is, the hydroxyl value of the first polyol is 20 mg KOH / g or more and 60 mg KOH / g or less, preferably 23 mg KOH / g or more and 58 mg KOH / g or less, more preferably 25 mg KOH / g or more and 55 mg KOH / g or less, and even more preferably 30 mg KOH / g or more and 55 mg KOH / g or less.

[0127] The content of oxyethylidene units relative to the total amount of oxyalkylene units in the first polyol (oxyethylidene content) is, for example, 10% by mass or more, preferably 11% by mass or more, more preferably 12% by mass or more, and even more preferably 13% by mass or more. Furthermore, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the first polyol (oxyethylidene content) is, for example, 80% by mass or less, preferably 78% by mass or less, and even more preferably 75% by mass or less. That is, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the first polyol (oxyethylidene content) is preferably 10% by mass or more and 80% by mass or less, preferably 11% by mass or more and 78% by mass or less, more preferably 12% by mass or more and 75% by mass or less, and even more preferably 13% by mass or more and 75% by mass or less.

[0128] The number average molecular weight (converted to polyethylene glycol) of the first polyol is, for example, 400 or more, preferably 1000 or more, more preferably 2000 or more, even more preferably 3000 or more, even more preferably greater than 4000, even more preferably 4100 or more, and particularly preferably 4500 or more. Furthermore, the number average molecular weight (converted to polyethylene glycol) of the first polyol is, for example, 15000 or less, preferably 10000 or less, more preferably 9000 or less, even more preferably 7000 or less, even more preferably 6000 or less, even more preferably 5800 or less, and particularly preferably 5500 or less. Therefore, the number average molecular weight of the first polyol is, for example, 400 or more and 15,000 or less, preferably 1,000 or more and 15,000 or less, more preferably 2,000 or more and 9,000 or less, even more preferably 3,000 or more and 7,000 or less, even more preferably greater than 4,000 and less than 6,000, even more preferably 4,100 or more and 5,800 or less, and especially preferably 4,500 or more and 5,500 or less.

[0129] In the second embodiment, the content ratio of the first polyol is the same as that in the first embodiment described above. More specifically, relative to the total amount of the first, second, and third polyols, the content ratio of the first polyol is 12% by mass or more, preferably 14% by mass or more, more preferably 16% by mass or more, and even more preferably 18% by mass or more. Furthermore, relative to the total amount of the first, second, and third polyols, the content ratio of the first polyol is 28% by mass or less, preferably 26% by mass or less, more preferably 24% by mass or less, and even more preferably 22% by mass or less.

[0130] (2) Second polyol In the second embodiment, the second polyol is, for example, the same as the second polyol described above in the first embodiment. That is, the second polyol has the above-described average number of functional groups, the above-described number of hydroxyl groups, and the above-described oxyethylidene content. Furthermore, the second polyol has, for example, the above-described number-average molecular weight. In the second embodiment, the content ratio of the second polyol is the same as the content ratio of the second polyol in the first embodiment described above.

[0131] (3) Third polyol In the second embodiment, the third polyol is, for example, the same as the third polyol described above in the first embodiment. That is, the third polyol has the above-described average number of functional groups, the above-described number of hydroxyl groups, and the above-described oxyethylidene content. Furthermore, the third polyol has, for example, the above-described number-average molecular weight. In the second embodiment, the content ratio of the third polyol is the same as the content ratio of the third polyol in the first embodiment described above.

[0132] (4) Other polyols The polyol composition may include other polyols as needed. The types and proportions of other polyols are the same as those in the first embodiment described above.

[0133] (5) Distance X In the second embodiment, the hydroxyl value and oxyethylidene content of the first polyol, the hydroxyl value and oxyethylidene content of the second polyol, and the hydroxyl value and oxyethylidene content of the third polyol satisfy a specified relationship.

[0134] More specifically, in the second embodiment, the parameter represented by the following formula (2) is a specified value or less. It should be noted that, hereinafter, the parameter represented by the following formula (2) will be referred to as "distance X (mgKOH / g + mass%)". The unit "mgKOH / g + mass%" of distance X will be omitted below.

[0135] Distance X = ({OHv2 - [(OHv1 + OHv3) / 2]} 2 +{R EO2 -[(R) EO1 +R EO3 ) / 2]} 2 ) 1 / 2 ···(2) It should be noted that in the above formula (2), the hydroxyl value of the first polyol is set as OHv1 (mgKOH / g), and the content ratio of the oxyethylidene unit at the molecule end of the first polyol relative to the total amount of oxyalkylene units of the first polyol is set as R. EO1 (mass %), the hydroxyl value of the second polyol is set as OHv2 (mgKOH / g), and the content ratio of the oxyethylidene unit of the second polyol relative to the total amount of oxyalkylene units of the second polyol is set as R. EO2 (mass %), the hydroxyl value of the third polyol is set as OHv3 (mgKOH / g), and the content ratio of the oxyethylidene unit of the third polyol relative to the total amount of oxyalkylene units of the third polyol is set as R. EO3 (quality%).

[0136] That is, in the above formula (2), OHv1 represents the hydroxyl value of the first polyol, OHv2 represents the hydroxyl value of the second polyol, and OHv3 represents the hydroxyl value of the third polyol. Additionally, in the above formula (2), R... EO1 R represents the oxyethylidene content of the first polyol. EO2 R represents the oxyethylidene content of the second polyol. EO3 This indicates the oxyethylidene content of the third polyol.

[0137] The distance X represented by the above formula (2) is an index representing the degree of hydrophilicity and hydrophobicity of the first polyol, the degree of hydrophilicity and hydrophobicity of the second polyol, and the degree of closeness to the degree of hydrophilicity and hydrophobicity of the third polyol.

[0138] More specifically, in the xy plane obtained by setting the x-axis to the polyoxyethylene content and the y-axis to the hydroxyl value, when the first polyol, the second polyol and the third polyol are plotted respectively, the midpoint between the first polyol and the third polyol and the distance X between the first polyol and the second polyol can be calculated using the above formula (2).

[0139] Furthermore, the specific value of the aforementioned distance X is below a predetermined value. More specifically, the distance X is 80 or less, preferably 75 or less, more preferably 70 or less, and even more preferably 65 or less. Additionally, there is no particular limitation on the lower limit of the distance X. For example, the distance X can be 5 or more, 10 or more, or 15 or more. That is, the distance X is, for example, 5 or more and 80 or less, preferably 10 or more and 80 or less, more preferably 15 or more and 80 or less, even more preferably 10 or more and 75 or less, even more preferably 15 or more and 70 or less, and particularly preferably 15 or more and 65 or less.

[0140] The distance X can be calculated using the above formula (2) from the hydroxyl value and oxyethylidene content of the first polyol, the hydroxyl value and oxyethylidene content of the second polyol, and the hydroxyl value and oxyethylidene content of the third polyol.

[0141] It should be noted that when the polyol composition contains multiple first polyols, multiple second polyols, and / or multiple third polyols, in the above formula (2), the weighted average of the mass basis of the hydroxyl group is used as the hydroxyl group, and the weighted average of the mass basis of the oxyethylidene content is used as the oxyethylidene content.

[0142] More specifically, when multiple first polyols are used together, in the above formula (2), OHv1 represents the weighted average of the mass basis of the hydroxyl values ​​of each first polyol, and R EO1 This represents the weighted average of the mass basis of the oxyethylidene content of each of the first polyols. Furthermore, when multiple second polyols are used together, in the above formula (2), OHv2 represents the weighted average of the mass basis of the hydroxyl values ​​of each second polyol, and R... EO2 This represents the weighted average of the mass basis of the oxyethylidene content of each of the second polyols. Furthermore, when multiple third polyols are used together, in the above formula (2), OHv3 represents the weighted average of the mass basis of the hydroxyl values ​​of each third polyol, and R... EO3 The weighted average of the mass benchmarks representing the oxyethylidene content of each first polyol.

[0143] (5) Preparation of polyol compositions There are no particular limitations on the method for manufacturing the polyol composition. For example, the first polyol, the second polyol, and the third polyol are selected such that the distance X represented by the above formula (2) is greater than or equal to the specified value. Then, the first polyol, the second polyol, and the third polyol are prepared in the above proportions respectively. In addition, other polyols are prepared as needed. Then, the first polyol, the second polyol, the third polyol, and other polyols prepared as needed are mixed using a known method. Thus, a polyol composition can be obtained.

[0144] (6) Effects Based on the above-described polyol composition, it is possible to manufacture polyurethane foams that have excellent low resilience and can suppress hardness changes in lower temperature regions (described later).

[0145] More specifically, in the polyol composition described above, the distance X represented by the above formula (2) is below the specified value. If the distance X is below the specified value, it is possible to manufacture a polyurethane foam with excellent low resilience and the ability to suppress hardness changes in a lower temperature region.

[0146] That is, when the distance X represented by the above formula (2) is large, the distance X indicates a large difference in the degree of hydrophilicity and hydrophobicity among the first, second, and third polyols. In such a case, the degree of phase separation among the first, second, and third polyols in the polyol composition is greater. Therefore, the phase separation rate during the manufacture of the polyurethane foam described later is greater. As a result, it is speculated that a polyurethane foam with a larger cell diameter and higher resilience can be obtained.

[0147] In contrast, when the distance X represented by the above formula (2) is small, the distance X indicates that the degree of hydrophilicity and hydrophobicity of the first, second, and third polyols are relatively similar. In such a case, the degree of phase separation of the first, second, and third polyols in the polyol composition is small. Therefore, the rate of phase separation during the manufacture of the polyurethane foam described later is small. As a result, it is speculated that a polyurethane foam with a smaller cell diameter and lower resilience can be obtained.

[0148] 3) Third implementation method The third embodiment of the present invention will now be described in detail. It should be noted that elements not described in detail below are the same as those in the first embodiment described above.

[0149] (1) Physical properties of the polyol composition In the third embodiment, the polyol composition has a specified average number of functional groups, a specified number of hydroxyl groups, and a specified oxyethylidene content.

[0150] More specifically, the average number of functional groups (average number of hydroxyl groups) of the polyol composition is, for example, 1.5 or more, preferably 1.8 or more, more preferably 2.0 or more, further preferably 2.3 or more, and especially preferably 2.8 or more. Additionally, the average number of functional groups (average number of hydroxyl groups) of the polyol composition is, for example, 4.5 or less, preferably 4.2 or less, more preferably 4.0 or less, further preferably 3.7 or less, and especially preferably 3.3 or less. That is, the average number of functional groups (average number of hydroxyl groups) of the polyol composition is, for example, 1.5 or more and 4.5 or less, preferably 1.8 or more and 4.2 or less, more preferably 2.0 or more and 4.0 or less, further preferably 2.3 or more and 3.7 or less, and especially preferably 2.8 or more and 3.3 or less. If the average number of functional groups (average number of hydroxyl groups) of the polyol composition is within the above range, a polyurethane foam (described later) with excellent low resilience and the ability to suppress hardness changes in lower temperature regions can be obtained. It should be noted that the average number of functional groups in a polyol composition is a weighted average of the average number of functional groups of each polyol contained in the composition. The weighted average number of functional groups can be calculated using known methods based on the molar ratio (mol%) of each polyol.

[0151] The hydroxyl value of the polyol composition is, for example, 80 mg KOH / g or more, preferably 85 mg KOH / g or more, more preferably 90 mg KOH / g or more, even more preferably 95 mg KOH / g or more, and particularly preferably 98 mg KOH / g or more. Furthermore, the hydroxyl value of the polyol composition is, for example, 120 mg KOH / g or less, preferably 115 mg KOH / g or less, more preferably 110 mg KOH / g or less, even more preferably 105 mg KOH / g or less, and particularly preferably 102 mg KOH / g or less. That is, the hydroxyl value of the polyol composition is, for example, 80 mg KOH / g or more and 120 mg KOH / g or less, preferably 85 mg KOH / g or more and 115 mg KOH / g or less, more preferably 90 mg KOH / g or more and 110 mg KOH / g or less, even more preferably 95 mg KOH / g or more and 105 mg KOH / g or less, and particularly preferably 98 mg KOH / g or more and 102 mg KOH / g or less. If the hydroxyl value of the polyol composition is within the above-mentioned range, a polyurethane foam with excellent low resilience and the ability to suppress hardness changes in a lower temperature range can be obtained (described later). It should be noted that the hydroxyl value of the polyol composition is a weighted average of the hydroxyl values ​​of the individual polyols contained in the composition. The weighted average of the hydroxyl values ​​can be calculated using known methods based on the mass ratio (mass%) of each polyol.

[0152] The content of oxyethylidene units relative to the total amount of oxyalkylene units in the polyol composition (oxyethylidene content) is, for example, 15.0% by mass or more, preferably 15.1% by mass or more, and more preferably 15.2% by mass or more. Furthermore, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the polyol composition (oxyethylidene content) is, for example, 17.3% by mass or less, preferably 17.2% by mass or less, and more preferably 17.1% by mass or less. That is, the content of oxyethylidene units relative to the total amount of oxyalkylene units in the polyol composition (oxyethylidene content) is, for example, 15.0% by mass or more and 17.3% by mass or less, preferably 15.1% by mass or more and 17.2% by mass or less, and more preferably 15.2% by mass or more and 17.1% by mass or less. It should be noted that the oxyethylidene content of the polyol composition is a weighted average of the oxyethylidene content of each polyol contained in the polyol composition. The weighted average of the oxyethylidene content can be calculated using known methods based on the mass ratio (mass%) of each polyol.

[0153] (2) Method for manufacturing polyol compositions The polyol composition may contain, for example, a polyol having the above-mentioned polyoxyalkylene unit, preferably a polyoxyalkylene polyol, and more preferably only a polyoxyalkylene polyol.

[0154] In addition, the polyol composition preferably contains a polyol having two or more of the above-mentioned polyoxyalkylene units, and more preferably contains a polyol having three or more of the above-mentioned polyoxyalkylene units.

[0155] Particularly preferred is that the polyol composition contains the first polyol, the second polyol, and the third polyol of the first embodiment in the same proportions as described in the first embodiment. Additionally, the polyol composition may contain other polyols as needed. The types and proportions of these other polyols are the same as those in the first embodiment described above.

[0156] There are no particular limitations on the method for manufacturing the polyol composition. For example, firstly, the first polyol, the second polyol, and the third polyol described above are prepared in the aforementioned proportions. Additionally, other polyols may be prepared as needed. Then, the first polyol, the second polyol, the third polyol, and any other polyols prepared as needed are mixed using a known method. Thus, the polyol composition is obtained.

[0157] (3) Effects Based on the above-described polyol composition, it is possible to manufacture polyurethane foams that have excellent low resilience and can suppress hardness changes in lower temperature regions (described later).

[0158] 2. Urethane foam composition (1) Formulation of urethane foam composition The urethane foam composition is a raw material composition used to manufacture polyurethane foam (described below). The urethane foam composition contains the above-described polyol composition (i.e., at least any one of the polyol compositions of embodiments 1 to 3 (hereinafter the same)).

[0159] More specifically, the urethane foam composition contains, for example, a polyisocyanate component and a polyol component. The urethane foam composition preferably consists of a polyisocyanate component and a polyol component.

[0160] [Polyisocyanate ingredient] Polyisocyanate components include, for example, industrially common polyisocyanate compounds. Examples of polyisocyanate compounds include, for example, chain-like aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates, and aromatic aliphatic polyisocyanates. Examples of chain-like aliphatic polyisocyanates include, for example, pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), and their derivatives. Examples of alicyclic polyisocyanates include, for example, isophorone diisocyanate (IPDI), norbornene diisocyanate (NBDI), and hydrogenated diphenylmethane diisocyanate (HDI). 12 MDI), hydrogenated diphenyl phthalene diisocyanate (H6XDI), and their derivatives are examples of aromatic polyisocyanates. Examples of aromatic aliphatic polyisocyanates include toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), phenyl diisocyanate (PDI), naphthalene diisocyanate (NDI), and their derivatives. Examples of aromatic aliphatic polyisocyanates include diphenyl phthalene diisocyanate (XDI), tetramethylphenyl diisocyanate (TMXDI), and their derivatives. Examples of derivatives include polymers, isocyanurate-modified products, urethane-modified products, polyol-modified products, biuret-modified products, urea-modified products, oxadiazine trione-modified products, and carbodiimide-modified products. Additionally, polymethylene polyphenyl polyisocyanate (crude MDI, polymeric MDI) is an example of a derivative. These can be used alone or in combination of two or more.

[0161] As polyisocyanate compounds, aromatic polyisocyanates are preferred, and diphenylmethane diisocyanate (MDI) and polymethylene polyphenyl polyisocyanate are more preferred. In other words, the polyisocyanate component preferably contains an aromatic polyisocyanate, and more preferably contains at least one polyisocyanate compound selected from the group consisting of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate. Using these compounds yields polyurethane foams with particularly excellent low resilience, particularly strong ability to suppress hardness changes in lower temperature ranges, and thus excellent compression set and colorfastness. Furthermore, using these compounds provides excellent moldability, enabling the manufacture of polyurethane foams by molding as described later. Polymethylene polyphenyl polyisocyanate is particularly preferred as a polyisocyanate compound.

[0162] The isocyanate group content of the polyisocyanate component, relative to the total amount of the polyisocyanate component, is, for example, 15% by mass or more, preferably 30% by mass or more. Furthermore, the isocyanate group content of the polyisocyanate component, relative to the total amount of the polyisocyanate component, is, for example, 60% by mass or less, preferably 50% by mass or less. That is, the isocyanate group content of the polyisocyanate component, relative to the total amount of the polyisocyanate component, is, for example, 15% by mass or more and 60% by mass or less, preferably 30% by mass or more and 50% by mass or less.

[0163] [Polyol Components] The polyol component contains the above-described polyol composition. For example, the polyol component contains the above-described first polyol, the above-described second polyol, and the above-described third polyol in the above-described proportions.

[0164] The polyol component may include the other components mentioned above, as needed. That is, the polyol component may also be a mixture (premix) of the first polyol, the second polyol, and the third polyol, and the other components mentioned above. Premixed polyols are preferred.

[0165] Other components include, for example, foaming agents, catalysts, and additives.

[0166] [Foaming Agent] Water can be cited as a foaming agent. Additionally, physical foaming agents can also be cited. Examples of physical foaming agents include hydrocarbons, halogenated hydrocarbons, carbon dioxide, and liquid carbon dioxide. They can be used alone or in combination of two or more.

[0167] The proportion of the foaming agent can be appropriately set according to the purpose and application. For example, when the foaming agent is water, the content of the foaming agent (water) relative to the total amount of the polyol composition is, for example, 0.1% by mass or more, preferably 0.5% by mass or more, and more preferably 0.7% by mass or more. Furthermore, the content of the foaming agent (water) relative to the total amount of the polyol composition is, for example, 5% by mass or less, preferably 3% by mass or less, and more preferably 1% by mass or less. That is, relative to the total amount of the polyol composition, the content of the foaming agent (water) is, for example, 0.1% by mass or more and 5% by mass or less, preferably 0.5% by mass or more and 3% by mass or less, and more preferably 0.7% by mass or more and 1% by mass or less.

[0168] [catalyst] Examples of catalysts include esterification catalysts. Examples of esterification catalysts include amine catalysts and metal catalysts. Examples of amine catalysts include tertiary amine catalysts, quaternary ammonium salts, and imidazoles. Examples of tertiary amine catalysts include triethylamine, triethylenediamine, bis(2-dimethylaminoethyl) ether, and N-methylmorpholine. Examples of quaternary ammonium salts include tetraethylammonium hydroxide. Examples of imidazoles include imidazoles and 2-ethyl-4-methylimidazolium. Examples of metal catalysts include organotin compounds, organolead compounds, organonitrile compounds, organocobalt compounds, organocopper compounds, and organobismuth compounds. Examples of organotin compounds include tin acetate, tin octanoate, tin oleate, tin laurate, dibutyltin diacetate, dimethyltin dilaurate, dibutyltin dilaurate, dibutyltin dithiol, dibutyltin maleate, dibutyltin dineodecanate, dioctyltin dithiol, dioctyltin dilaurate, and dibutyltin dichloride. Examples of organolead compounds include lead octanoate and lead naphthenate. Examples of organonitrile compounds include nickel naphthenate. Examples of organocobalt compounds include cobalt naphthenate. Examples of organocopper compounds include copper ocenoate. Examples of organobismuth compounds include bismuth octanoate and bismuth neodecanoate. These compounds can be used alone or in combination of two or more.

[0169] Amine catalysts are preferred as catalysts. Amine catalysts are miscible with foaming agents (water), thus exhibiting excellent operability. Therefore, amine catalysts are suitable for the preparation of premixes.

[0170] Furthermore, it is particularly preferred that diphenylmethane diisocyanate and / or polymethylene polyphenyl polyisocyanate are used as the polyisocyanate component, and that the catalyst comprises an amine catalyst but not a metal catalyst. In this case, a metal-free polyurethane foam can be obtained, and excellent workability and excellent moldability can be achieved simultaneously.

[0171] The proportion of catalyst can be appropriately set according to the purpose and application. For example, the proportion of catalyst relative to the total amount of the polyol composition is, for example, 0.1% by mass or more, preferably 0.2% by mass or more, and more preferably 0.3% by mass or more. Furthermore, the proportion of catalyst relative to the total amount of the polyol composition is, for example, 5% by mass or less, preferably 3% by mass or less, and more preferably 1% by mass or less. That is, the proportion of catalyst relative to the total amount of the polyol composition is, for example, 0.1% by mass or more and 5% by mass or less, preferably 0.2% by mass or more and 3% by mass or less, and more preferably 0.3% by mass or more and 1% by mass or less.

[0172] [additive] Examples of additives include crosslinking agents, foam stabilizers, plasticizers, fillers, antioxidants, compatibilizers, colorants, stabilizers, and UV absorbers. These can be used alone or in combination of two or more. Foam stabilizers are preferred as additives. Examples of foam stabilizers include silicone-based foam stabilizers, and more specifically, siloxane-polyether block copolymers.

[0173] The proportion of additives can be appropriately set according to the purpose and application. For example, the proportion of foam stabilizer relative to the total amount of the polyol composition is, for example, 0.01 parts by weight to 2.0 parts by weight.

[0174] [Premix manufacturing method] There are no particular limitations on the manufacturing method of the premix. For example, a premix can be obtained by mixing a polyol composition with other components (preferably a foaming agent, a catalyst, and a foam stabilizer) using known methods.

[0175] (2) Effects Based on the above-described urethane foam composition, it is possible to manufacture a polyurethane foam with excellent low resilience and the ability to suppress hardness changes in lower temperature regions (described later).

[0176] 3. Polyurethane foam (1) Manufacturing method of polyurethane foam Polyurethane foam can be obtained by reacting the above-mentioned urethane foam composition. More specifically, polyurethane foam is a foamed polyurethane resin obtained by reacting and foaming the urethane foam composition.

[0177] There are no particular limitations on the method of manufacturing polyurethane foam. For example, firstly, as a urethane foam composition, the above-mentioned polyisocyanate component and the above-mentioned polyol component (preferably a premix) are prepared.

[0178] Next, the aforementioned polyisocyanate component and the aforementioned polyol component (preferably a premix) are mixed using a known method and reacted. That is, the aforementioned polyisocyanate compound and the aforementioned polyol composition are reacted and foamed in the presence of a catalyst and a foaming agent. Known methods can be used as the reaction method and the foaming method. Examples include slab processing, mold processing, and spray processing; slab processing and mold processing are preferred, and mold processing is more preferred. It should be noted that the reaction conditions can be appropriately set according to its purpose and application.

[0179] The ratio of polyisocyanate components to polyol components can be adjusted based on, for example, the isocyanate index of the urethane foam composition. The isocyanate index is the stoichiometric ratio of isocyanate groups and active hydrogen groups, expressed, for example, by the following formula.

[0180] Isocyanate index = [Isocyanate groups in the urethane foam composition / Active hydrogen groups in the urethane foam composition] × 100 The isocyanate index of the urethane foam composition is, for example, 50 or more, preferably 60 or more, and more preferably 70 or more. The isocyanate index of the urethane foam composition is, for example, 200 or less, preferably 140 or less, and more preferably 120 or less. That is, the isocyanate index of the urethane foam composition is, for example, 50 or more and 200 or less, preferably 60 or more and 140 or less, and more preferably 70 or more and 120 or less.

[0181] Then, if the above-mentioned polyisocyanate component and the above-mentioned polyol component (preferably a premix) are mixed, the above-mentioned polyisocyanate compound and the above-mentioned polyol composition react in the presence of a catalyst to obtain a polyurethane resin. Furthermore, due to the action of a foaming agent, the polyurethane resin becomes foamed. Thus, a polyurethane foam (foamed polyurethane resin) is obtained.

[0182] (2) Physical properties of polyurethane foam [tanδ and glass transition temperature] The polyurethane foam described above has a glass transition temperature in a specified first temperature range and a specified second temperature range, respectively.

[0183] The first temperature range is -70°C or higher, preferably -65°C or higher, more preferably -60°C or higher, and even more preferably -58°C or higher. Furthermore, the first temperature range is -30°C or lower, preferably -35°C or lower, more preferably -40°C or lower, and even more preferably -50°C or lower. That is, the first temperature range is -70°C or higher and -30°C or lower, preferably -65°C or higher and -35°C or lower, more preferably -60°C or higher and -40°C or lower, and even more preferably -58°C or higher and -50°C or lower.

[0184] The second temperature range is 0°C or higher, preferably 15°C or higher, more preferably 20°C or higher, and even more preferably 25°C or higher. Furthermore, the second temperature range is 60°C or lower, preferably 50°C or lower, more preferably 40°C or lower, and even more preferably 30°C or lower. That is, the second temperature range is 0°C or higher and 60°C or lower, preferably 15°C or higher and 50°C or lower, more preferably 20°C or higher and 40°C or lower, and even more preferably 25°C or higher and 30°C or lower.

[0185] The glass transition temperature is the temperature at which a state change occurs from glass to rubber. It is expressed as the peak value (positive peak) of tanδ, measured by dynamic viscoelasticity determination in a compression mode with a vibrational frequency of 10 Hz.

[0186] That is, at least one peak value of tanδ in the polyurethane foam can be identified within the first temperature range (-70℃ to -30℃), preferably one. In addition, at least one peak value of tanδ in the polyurethane foam can be identified within the second temperature range (0℃ to 60℃), preferably one.

[0187] The peak value of tanδ within the first temperature range (-70℃ to -30℃) is, for example, 0.01 or more, preferably 0.02 or more, more preferably 0.03 or more, and even more preferably 0.05 or more. Furthermore, the peak value of tanδ within the first temperature range (-70℃ to -30℃) is 0.10 or less, preferably 0.09 or less, more preferably 0.08 or less, and even more preferably 0.07 or less. That is, the peak value of tanδ within the first temperature range (-70℃ to -30℃) is, for example, 0.01 or more and 0.10 or less, preferably 0.02 or more and 0.09 or less, more preferably 0.03 or more and 0.08 or less, and even more preferably 0.05 or more and 0.07 or less.

[0188] The peak temperature of tanδ (first glass transition temperature) within the first temperature range is, for example, -70°C or higher, preferably -65°C or higher, more preferably -60°C or higher, and even more preferably -58°C or higher. Furthermore, the peak temperature of tanδ (first glass transition temperature) within the first temperature range is, for example, -30°C or lower, preferably -35°C or lower, more preferably -40°C or lower, and even more preferably -50°C or lower. That is, the peak temperature of tanδ (first glass transition temperature) within the first temperature range is, for example, -70°C or higher and -30°C or lower, preferably -65°C or higher and -35°C or lower, more preferably -60°C or higher and -40°C or lower, and even more preferably -58°C or higher and -50°C or lower.

[0189] The peak value of tanδ within the second temperature range (0℃~60℃) is 0.30 or higher, preferably 0.35 or higher, more preferably 0.45 or higher, and even more preferably 0.48 or higher. Furthermore, the peak value of tanδ within the second temperature range (0℃~60℃) is, for example, 1.00 or lower, preferably 0.90 or lower, more preferably 0.80 or lower, and even more preferably 0.70 or lower. That is, the peak value of tanδ within the second temperature range (0℃~60℃) is 0.30 or higher and 1.00 or lower, preferably 0.35 or higher and 0.90 or lower, more preferably 0.45 or higher and 0.80 or lower, and even more preferably 0.48 or higher and 0.70 or lower.

[0190] The peak temperature of tanδ (second glass transition temperature) within the second temperature range is, for example, 0°C or higher, preferably 15°C or higher, more preferably 20°C or higher, and even more preferably 25°C or higher. Furthermore, the peak temperature of tanδ (second glass transition temperature) within the second temperature range is, for example, 60°C or lower, preferably 50°C or lower, more preferably 40°C or lower, and even more preferably 30°C or lower. That is, the peak temperature of tanδ (second glass transition temperature) within the second temperature range is, for example, 0°C or higher and 60°C or lower, preferably 15°C or higher and 50°C or lower, more preferably 20°C or higher and 40°C or lower, and even more preferably 25°C or higher and 30°C or lower.

[0191] Moreover, the polyurethane foam described above has a high tanδ value at -25°C.

[0192] That is, when the polyol composition contains a second polyol and a third polyol, the peak value of tanδ of the polyurethane foam can be identified in the first temperature range and the second temperature range. Moreover, between the peak value of tanδ in the first temperature range (positive peak) and the peak value of tanδ in the second temperature range (positive peak), tanδ decreases, producing a negative peak (valley).

[0193] At this point, when the polyol composition does not contain the first polyol, the negative peak (peak trough) becomes larger. Therefore, the tanδ value at -25°C is lower than the tanδ value at -25°C when the polyol composition contains the first polyol.

[0194] In contrast, when the polyol composition contains the first polyol, the negative peak (peak valley) becomes smaller. Therefore, the tanδ value at -25°C is higher when the polyol composition contains the first polyol than when the polyol composition does not contain the first polyol.

[0195] More specifically, the tanδ value at -25°C is 0.095 or higher, preferably 0.098 or higher, more preferably 0.10 or higher, and even more preferably 0.11 or higher. Additionally, the tanδ value at -25°C is, for example, 0.90 or lower, preferably 0.70 or lower, more preferably 0.50 or lower, and even more preferably 0.30 or lower. That is, the tanδ value at -25°C is 0.095 or higher and 0.90 or lower, preferably 0.098 or higher and 0.70 or lower, more preferably 0.10 or higher and 0.50 or lower, and even more preferably 0.11 or higher and 0.30 or lower.

[0196] If the tanδ of the polyurethane foam meets the above conditions, a polyurethane foam with excellent low resilience and the ability to suppress hardness changes in a lower temperature range can be manufactured.

[0197] The tanδ and glass transition temperature can be adjusted, for example, by the average number of functional groups, hydroxyl value, and oxyethylidene content of the polyol components. For example, by using the first, second, and third polyols in the proportions described above, the tanδ and glass transition temperature can be easily adjusted to the ranges mentioned above.

[0198] Furthermore, the tanδ and glass transition temperature can be adjusted by the type and amount of polyisocyanate components. Additionally, the tanδ and glass transition temperature can be adjusted by the type and amount of blowing agent. Furthermore, the tanδ and glass transition temperature can be adjusted by the type and amount of catalyst.

[0199] [Viscoelasticity] The storage modulus (E') of the polyurethane foam was, for example, measured simultaneously with the aforementioned tanδ determination by dynamic viscoelasticity measurement in compression mode at a vibration frequency of 10 Hz. It should be noted that details of the dynamic viscoelasticity measurement are described below as examples.

[0200] From the viewpoint of low resilience of polyurethane foam, a lower storage modulus of elasticity (E') is preferable. More specifically, for example, over the entire temperature range above 0°C, the storage modulus of elasticity (E') of the polyurethane foam is, for example, 5 MPa or less, preferably 3 MPa or less. Furthermore, the storage modulus of elasticity (E') of the polyurethane foam is, for example, 0.001 MPa or more. When the storage modulus of elasticity (E') of the polyurethane foam is below the aforementioned upper limit over the entire temperature range above 0°C, excellent low resilience can be obtained at lower temperatures. Therefore, polyurethane foam can be appropriately used in cold regions.

[0201] [hardness] The hardness of polyurethane foam can be measured, for example, by push-pull hardness. Push-pull hardness is measured using a push-pull hardness tester (product number RZ-10, manufactured by Aikoh Engineering). Push-pull hardness represents the maximum value required to indent the polyurethane foam to 40% strain using a cylindrical contact clamp with a diameter of 20 mm. Push-pull hardness quantifies the tactile sensation of pressing the polyurethane foam with a finger.

[0202] For example, at 25°C, the push-pull hardness of the polyurethane foam is, for example, 8.6 or less, preferably 8.5 or less, more preferably 8.4 or less, and even more preferably 8.3 or less. Additionally, at 25°C, the push-pull hardness of the polyurethane foam is, for example, 6.0 or more, preferably 7.0 or more. That is, at 25°C, the push-pull hardness of the polyurethane foam is, for example, 6.0 or more and 8.6 or less, preferably 6.0 or more and 8.5 or less, more preferably 7.0 or more and 8.4 or less, and even more preferably 7.0 or more and 8.3 or less.

[0203] Furthermore, at 2°C, the push-pull hardness of the polyurethane foam is, for example, 60.0 or less, preferably 50.0 or less, more preferably 45.0 or less, and even more preferably 40.0 or less. Additionally, at 2°C, the push-pull hardness of the polyurethane foam is, for example, 10.0 or more, preferably 20.0 or more. That is, at 2°C, the push-pull hardness of the polyurethane foam is, for example, 10.0 or more and 60.0 or less, preferably 10.0 or more and 50.0 or less, more preferably 20.0 or more and 45.0 or less, and even more preferably 20.0 or more and 40.0 or less.

[0204] Furthermore, the ratio of the push-pull hardness at 2°C to the push-pull hardness at 25°C (push-pull hardness at 2°C / push-pull hardness at 25°C) is, for example, 7.0 or less, preferably 6.0 or less, and more preferably 5.0 or less. It should be noted that the ratio of the push-pull hardness at 2°C to the push-pull hardness at 25°C (push-pull hardness at 2°C / push-pull hardness at 25°C) is, for example, 1.0 or more. That is, the ratio of the push-pull hardness at 2°C to the push-pull hardness at 25°C (push-pull hardness at 2°C / push-pull hardness at 25°C) is, for example, 1.0 or more and 7.0 or less, preferably 1.0 or more and 6.0 or less, and more preferably 1.0 or more and 5.0 or less.

[0205] [Resilience] The resilience of the polyurethane foam obtained according to the method described in JIS K-6400 (1997) is, for example, 10% or less, preferably 8% or less, and more preferably 6% or less. Furthermore, the resilience of the polyurethane foam obtained according to the method described in JIS K-6400 (1997) is, for example, 1% or more. That is, the resilience of the polyurethane foam obtained according to the method described in JIS K-6400 (1997) is, for example, 1% or more and 10% or less, preferably 1% or more and 8% or less, and more preferably 1% or more and 6% or less.

[0206] In particular, from the viewpoint of obtaining a polyurethane foam with low resilience (low-resilience polyurethane foam), it is preferable that the ratio of push-pull hardness at 2°C to push-pull hardness at 25°C (push-pull hardness at 2°C / push-pull hardness at 25°C) is a specified value or higher, and the resilience is a specified value or lower.

[0207] More specifically, in the aforementioned polyurethane foam, it is preferable that the ratio of push-pull hardness at 2°C to push-pull hardness at 25°C is 7.0 or less, and the resilience is 8% or less. More preferably, the ratio of push-pull hardness at 2°C to push-pull hardness at 25°C is 6.0 or less, and the resilience is 7% or less. Even more preferably, the ratio of push-pull hardness at 2°C to push-pull hardness at 25°C is 5.0 or less, and the resilience is 7% or less.

[0208] [density] From the perspective of degradation (inhibiting elasticity reduction), the density of polyurethane foam is, for example, 10 kg / m³. 3 That's all. Additionally, from a lightweight perspective, the density of polyurethane foam is, for example, 80 kg / m³. 3 the following.

[0209] [Compression permanent strain] The compressive set strain of polyurethane foam can be determined according to the method described in JIS K-6400 (1997). It should be noted that the following conditions can be used as the conditions for determining the compressive set strain: “50%-DrySet”, “75%-DrySet”, and “50%-WetSet”.

[0210] 50%-DrySet: Compress the test object (polyurethane foam) to 50% of its thickness and set the placement conditions to 70°C, 50% relative humidity, and 22 hours.

[0211] 50%-WetSet: Compress the test object (polyurethane foam) to 50% of its thickness and set the placement conditions to 50°C, 95% relative humidity, and 22 hours.

[0212] 75%-DrySet: Compress the test object (polyurethane foam) to 75% of its thickness and set the placement conditions to 70°C, 50% relative humidity, and 22 hours.

[0213] Furthermore, the compressive permanent strain of the polyurethane foam under 50%-DrySet conditions is, for example, 3.0% or less, preferably 2.5% or less, more preferably 2.1% or less, and even more preferably 1.8% or less. It should be noted that the compressive permanent strain of the polyurethane foam under 50%-DrySet conditions is, for example, 1.0% or more.

[0214] Furthermore, the compressive stress of the polyurethane foam under 75%-DrySet conditions is, for example, 8.0% or less, preferably 6.5% or less, more preferably 5.0% or less, and even more preferably 4.7% or less. It should be noted that the compressive stress of the polyurethane foam under 75%-DrySet conditions is, for example, 1.0% or more.

[0215] Furthermore, the compressive permanent strain of the polyurethane foam under 50%-WetSet conditions is, for example, 3.0% or less, preferably 2.5% or less, and more preferably 2.0% or less. It should be noted that the compressive permanent strain of the polyurethane foam under 50%-WetSet conditions is, for example, 1.0% or more.

[0216] (3) Effects The polyurethane foam described above is obtained using the aforementioned polyol composition, and therefore exhibits excellent low resilience and can suppress hardness changes in lower temperature regions.

[0217] Furthermore, the aforementioned polyurethane foam exhibits excellent healthy bubble properties. That is, during the manufacturing process of the polyurethane foam, gas generated inside the foam breaks down the cell membrane and escapes from the foam. Therefore, the polyurethane foam possesses excellent air permeability even when not supplied to the interconnection process.

[0218] (4) Applications of polyurethane foam Regarding the polyurethane foam described above, it exhibits excellent low resilience and excellent hardness not only in the room temperature range but also in lower temperature ranges. That is, the polyurethane foam described above is preferably a low resilience polyurethane foam.

[0219] Therefore, the aforementioned polyurethane foam can be widely used in molded bodies requiring low resilience. As a molded body, it is suitable for use as, for example, pressure-resistant dispersion materials, shape-retaining materials, sound-absorbing materials, impact-absorbing materials, vibration-absorbing materials, optical materials, and cushioning materials. As a cushioning material, examples include cushioning materials for furniture and bedding. Examples of furniture and bedding include cushions, mattresses, pillows, sofas, seat cushions, and chairs.

[0220] In addition, the aforementioned polyurethane foam is suitable for use in various industrial sectors. These sectors include, for example, consumer goods, automotive, electronic materials, medical, clothing, and hygiene materials. Applications include, for example, washing sponges, filters, pads, sporting goods, protective gear, hydroponic mats, food cushioning pads, seats, headrests, nursing cushioning materials, relaxation mats, wig retainers, covers, flooring materials, makeup puffs, rollers, electronic components, abrasive pads, sanitary products, diapers, and robot exterior components.

[0221] In particular, the aforementioned polyurethane foam is suitable for use as cushions and mattresses. That is, cushions and mattresses are preferred as molded bodies. Cushions and mattresses containing the aforementioned polyurethane foam have excellent low resilience and excellent firmness, and are therefore suitable for use in various industrial fields, especially furniture and bedding.

[0222] Example The present invention will now be described in more detail with reference to embodiments, but the invention is not limited to these embodiments. The materials, amounts, proportions, and processing steps shown in the following embodiments may be suitably varied without departing from the spirit of the invention.

[0223] [1] Measurement methods and evaluation methods The following methods are used to measure and evaluate various physical properties.

[0224] [1.1] Cream Time This refers to the time during which the raw material composition of polyurethane foam remains in a liquid (creamy) state. The time from mixing the raw material composition of polyurethane foam to the start of the resinification reaction (curing reaction) and foaming was measured.

[0225] [1.2] Foaming time This refers to the stand-up time of the polyurethane foam raw material composition. It measures the time from when the polyurethane foam raw material composition is mixed and injected into a mold until the foam reaches its maximum height after maximal foaming.

[0226] [1.3] Healthy Bubbles During the manufacturing process of polyurethane foam, the foaming state of the polyurethane foam surface inside the box-shaped container (rectangular, 25cm x 25cm at the bottom and top) is visually confirmed and evaluated according to the following criteria.

[0227] ×: When viewed from above, the air bubbles are not visible at all.

[0228] 〇: When looking down at the box-shaped container, 1 to 4 air bubbles can be identified.

[0229] ◎: When viewed from above, more than 5 air bubbles can be observed on the surface of the foam.

[0230] [1.4] Shrinkage of polyurethane foam The shrinkage status of the polyurethane foam is visually confirmed and evaluated according to the following criteria.

[0231] ×: Wrinkles can be identified on the entire surface of the foam due to shrinkage, and the original shape is not preserved.

[0232] 〇: Due to shrinkage, wrinkles can only be observed on the side of the foam.

[0233] ◎: Contraction could not be confirmed.

[0234] [1.5] Density of polyurethane foam The density of polyurethane foam was determined according to JISK-7222 (2005).

[0235] [1.6] Resilience of polyurethane foam The resilience of polyurethane foam was measured according to the method described in JISK-6400 (1997).

[0236] [1.7] Recovery Time The polyurethane foam was cut into 100×100×50 mm (thickness) pieces to obtain samples. A finger was used to press an indentation into the sample from the surface up to a thickness of 5 mm for 20 seconds. Then, the time from when the finger was removed from the sample until the sample returned to its original shape was measured.

[0237] [1.8] Compression permanent strain of polyurethane foam The compression set was measured according to the method described in JISK-6400 (1997). More specifically, the core of a polyurethane foam was cut into 50mm × 50mm × 25mm (thickness) pieces to obtain samples. The samples were compressed until the thickness reached the following proportions and then clamped in a parallel flat plate.

[0238] The sample was placed in a compressed state under the following conditions (compression test). Then, the sample was removed and left at room temperature for 30 minutes. The thickness of the sample was then measured. The thickness before and after the compression test was then compared to calculate the strain rate (%).

[0239] It should be noted that the sample was compressed to 50% thickness, and the storage conditions were set to 70°C, 50% relative humidity, and 22 hours. This sample was used as the sample for the 50%-DrySet.

[0240] Additionally, the sample was compressed to 50% thickness, and the storage conditions were set to 50°C, 95% relative humidity, and 22 hours. This sample was then used as the 50%-WetSet sample.

[0241] Additionally, the sample was compressed to 75% thickness, and the storage conditions were set at 70°C, 50% relative humidity, and 22 hours. This sample was then used as the 75%-DrySet sample.

[0242] [1.9] Dynamic viscoelasticity test Polyurethane foam was cut into cuboid samples with a length of 2.0 cm × a cross-section of 2.0 cm × 1.0 cm. The dynamic viscoelasticity of the cuboid samples was measured using a VES-F-IIIVISCO-ELASTICSPECTROMETER (manufactured by Iwamoto Manufacturing Co., Ltd.). It should be noted that the measurement conditions are as described below. The glass transition temperature, tanδ value, peak tanδ value, and storage modulus (E') were calculated from the obtained data.

[0243] Measurement temperature: -150~250℃ Heating rate: 5℃ / minute Vibration frequency: 10 Hz Compressive strain: 0.08% Compression mode [1.10] Push-pull hardness The push-pull hardness of polyurethane foam was measured using a push-pull hardness tester (product number RZ-10, manufactured by Aikoh Engineering). More specifically, the polyurethane foam was indented to a strain of 40% using a cylindrical contact clamp with a diameter of 20 mm, and the maximum value was read.

[0244] [1.11] Distance X The distance X of the polyol composition is calculated based on the following formula (2).

[0245] Distance X = ({OHv2 - [(OHv1 + OHv3) / 2]} 2 +{R EO2 -[(R) EO1 +R EO3 ) / 2]} 2 ) 1 / 2 ···(2) In formula (2) above, OHv1 represents the hydroxyl value of the first polyol, OHv2 represents the hydroxyl value of the second polyol, and OHv3 represents the hydroxyl value of the third polyol. Additionally, in formula (2) above, R... EO1 R represents the oxyethylidene content of the first polyol. EO2 R represents the oxyethylidene content of the second polyol. EO3 This indicates the oxyethylidene content of the third polyol.

[0246] [2] Use of raw materials The following raw materials are used in the manufacture of polyurethane foam.

[0247] [2.1] Polyol composition (a) (1) First polyol A The polyoxyalkylene polyol (a block copolymer of propylene oxide and ethylene oxide, terminal oxyethylene type) has a terminal oxyethylene unit ratio (oxyethylene content) of 15% by mass relative to the total amount of alkylene units, an average number of functional groups of 3, a number average molecular weight of 5000, and a hydroxyl value of 34 mgKOH / g. (2) Second polyol B The polyoxyalkylene polyol has an oxyethylene unit ratio (oxyethylene content) of 0% by mass relative to the total amount of oxyalkylene units, an oxypropylene unit ratio of 100% by mass, an average functional group number of 2.9, and a hydroxyl value of 32 mg KOH / g. (3) Third polyol C The polyoxyalkylene polyol has an oxyethylene unit ratio (oxyethylene content) of 21.8% by mass relative to the total oxyalkylene units, an oxypropylene unit ratio of 78.2% by mass, an average functional group number of 3, and a hydroxyl value of 145 mg KOH / g. (4) Other polyols (the first polyol in the second embodiment) D The polyoxyalkylene polyol (a random copolymer of propylene oxide and ethylene oxide) has an oxyethylene unit ratio (oxyethylene content) of 70% by mass relative to the total amount of alkylene units, an average number of functional groups of 3, a number average molecular weight of 3360, and a hydroxyl value of 52 mgKOH / g. (5) Second polyol E A mixture of phthalic acid-modified polyether polyol and unmodified polyether polyol (phthalic acid-modified polyether polyol: unmodified polyether polyol = 75:25 (mass ratio)) has an oxyethylidene unit ratio (oxyethylidene content) of 0% by mass relative to the total amount of oxyalkylene units, an average number of functional groups of 3, and a hydroxyl value of 56 mg KOH / g. (6) First polyol F The polyoxyalkylene polyol (oxyethylene-oxypropylene copolymer) has an oxyethylene content of 20% by mass relative to the total amount of alkylene units and an oxypropylene content of 80% by mass, with an average of 2 functional groups and a hydroxyl value of 28 mg KOH / g. (7) Other polyols G Dipropylene glycol (DPG), manufactured by Tokyo Chemical Industry Co., Ltd. [2.2] Polyisocyanates (1) TDI Toluene diisocyanate, a mixture of the 2,4-isomer and the 2,6-isomer (2,4-isomer: 2,6-isomer = 80:20 (mass ratio)), trade name TAKENATE T-80 (manufactured by Mitsui Chemicals). (2) p-MDI Polymethylene polyphenyl polyisocyanate, with an NCO content of 32.8-33.4% by mass as measured according to ASTM D1638, trade name COSMONATE SI-100 (manufactured by Kumho Mitsui Chemicals Co., Ltd.) [2.3] Additives (1) Foam stabilizer 1 Trade name VORASURF SRX-294 (manufactured by Dow-Toray), Si-C type organosilicon polyether copolymer (2) Foam stabilizer 2 Product name: TEGOSTAB BF-2470 (manufactured by EVONIK), silicone surfactant. [3] Examples and Comparative Examples Examples 1-3 and Comparative Examples 1-11 According to the formulation shown in Table 1, a polyol composition was prepared. In addition, the polyol composition and additives were mixed to obtain a polyol component (premix).

[0248] In addition, water (a blowing agent) was incorporated as an additive into the polyol component (premix). In Examples 1-3, Comparative Examples 1-8, and Comparative Example 10, the proportion of water (a blowing agent) was 2.5 parts by weight relative to 100 parts by weight of the polyol composition. In Comparative Examples 9 and 11, the proportion of water (a blowing agent) was 2.3 parts by weight relative to 100 parts by weight of the polyol composition.

[0249] In addition, a catalyst was incorporated as an additive into the polyol component (premix). In Examples 1-3, Comparative Examples 1-8, and Comparative Example 10, the catalyst used was DABCO 33-LV (manufactured by EVONIK, a 33% by mass diethylene glycol solution of triethylenediamine). The proportion of DABCO 33-LV was 0.5 parts by mass (solid component) relative to 100 parts by mass of the polyol composition. In Comparative Examples 9 and 11, the catalysts used were DABCO 33-LV (manufactured by EVONIK, a 33% by mass diethylene glycol solution of triethylenediamine) and DABCOT-9 (manufactured by Air Products and Chemicals, Inc., tin octoate). The proportion of DABCO 33-LV was 0.3 parts by mass (solid component) relative to 100 parts by mass of the polyol composition. In addition, the proportion of the product under the trade name DABCO T-9 is 0.1 parts by weight (solid component) relative to 100 parts by weight of the polyol composition.

[0250] Next, the polyisocyanate component was prepared according to the formulation shown in Table 1. This yielded the urethane foam composition.

[0251] Then, according to the isocyanate index shown in Table 1, the polyol component (premix) and the polyisocyanate component are combined. It should be noted that the isocyanate index is calculated using the following formula.

[0252] Isocyanate index = [Isocyanate groups in the urethane foam composition / Active hydrogen groups in the urethane foam composition] × 100 Next, the mixture of polyol (premix) and polyisocyanate was placed into a rectangular container (25cm x 25cm at the bottom and top) for foaming and curing. This yielded polyurethane foam. The polyurethane foam was then allowed to stand at room temperature for one day. The physical properties of the polyurethane foam were then measured using the method described above. The results are shown in Table 1.

[0253] In addition, the temperature curves of tanδ obtained by dynamic viscoelasticity test of the polyurethane foams of Example 2, Comparative Example 10, and Comparative Example 11 are shown below. Figure 1 Furthermore, the temperature curves of the storage modulus (E') of the polyurethane foams of Example 2, Comparative Example 10, and Comparative Example 11, measured by dynamic viscoelasticity testing, are shown below. Figure 2 .

[0254] [Table 1] It should be noted that the above-described invention is provided as an illustrative embodiment of the present invention, but it is merely illustrative and not intended to be limiting. Modifications of the present invention that will be apparent to those skilled in the art are included in the appended claims.

[0255] Industrial availability The polyol compositions, urethane foam compositions, polyurethane foams and molded bodies of the present invention are suitable for use in the fields of daily necessities, automobiles, electronic materials, medical, clothing and hygiene materials.

Claims

1. A polyol composition comprising a first polyol, a second polyol, and a third polyol, the average functionality of the first polyol is 1.5 or more and 4.5 or less, the hydroxyl value of the first polyol is 20 mgKOH / g or more and 50 mgKOH / g or less, the content ratio of oxyethylene units at the molecular terminals of the first polyol is 10 mass% or more and 60 mass% or less relative to the total amount of oxyalkylene units of the first polyol, the average functionality of the second polyol is 1.5 or more and 4.5 or less, the hydroxyl value of the second polyol is 20 mgKOH / g or more and 70 mgKOH / g or less, the content ratio of oxyethylene units of the second polyol is less than 10 mass% relative to the total amount of oxyalkylene units of the second polyol, the average functionality of the third polyol is 1.5 or more and 4.5 or less, the hydroxyl value of the third polyol is 120 mgKOH / g or more and 300 mgKOH / g or less, the content ratio of oxyethylene units of the third polyol is 10 mass% or more relative to the total amount of oxyalkylene units of the third polyol, the total amount of the first polyol, the second polyol, and the third polyol is the content ratio of the first polyol is 12 mass% or more and 28 mass% or less, the content ratio of the second polyol is 12 mass% or more and 28 mass% or less, the content ratio of the third polyol is 52 mass% or more and 68 mass% or less.

2. A polyol composition comprising a first polyol, a second polyol, and a third polyol, the average functionality of the first polyol is 1.5 or more and 4.5 or less, the hydroxyl value of the first polyol is 20 mgKOH / g or more and 60 mgKOH / g or less, the content ratio of oxyethylene units at the molecular terminals of the first polyol is 10 mass% or more and 80 mass% or less relative to the total amount of oxyalkylene units of the first polyol, the average functionality of the second polyol is 1.5 or more and 4.5 or less, the hydroxyl value of the second polyol is 20 mgKOH / g or more and 70 mgKOH / g or less, the content ratio of oxyethylene units of the second polyol is less than 10 mass% relative to the total amount of oxyalkylene units of the second polyol, the average functionality of the third polyol is 1.5 or more and 4.5 or less, the hydroxyl value of the third polyol is 120 mgKOH / g or more and 300 mgKOH / g or less, the content ratio of oxyethylene units of the third polyol is 10 mass% or more relative to the total amount of oxyalkylene units of the third polyol, the total amount of the first polyol, the second polyol, and the third polyol is the content ratio of the first polyol is 12 mass% or more and 28 mass% or less, the content ratio of the second polyol is 12 mass% or more and 28 mass% or less, the content ratio of the third polyol is 52 mass% or more and 68 mass% or less, the hydroxyl value of the first polyol is set to OHvl (mgKOH / g), and the content ratio of the molecular terminal ethylene oxide unit of the first polyol relative to the total amount of the oxyalkylene unit of the first polyol is set to R EO1 (mass %), the hydroxyl value of the second polyol is set to OHv2 (mgKOH / g), and the content ratio of the oxyethylene unit of the second polyol relative to the total amount of the oxyalkylene unit of the second polyol is set to R EO2 (mass %), the hydroxyl value of the third polyol is set to OHv3 (mgKOH / g), and the content ratio of the oxyethylene unit of the third polyol relative to the total amount of the oxyalkylene unit of the third polyol is set to R EO3 (mass %), the distance X (mgKOH / g + mass %) represented by the following formula (1) is 80 or less, Distance X = {OHv2- [ (OHv1+ OHv3) / 2]} 2 + {R EO2 - [ (R EO1 + R EO3 ) / 2]} 2 ) 1 / 2 ……(2).

3. The polyol composition of claim 1 or claim 2, wherein, The first polyol has a content ratio of ethylene oxide units of 12% by mass or more and 30% by mass or less relative to the total amount of oxyalkylene units of the first polyol.

4. The polyol composition of claim 1 or claim 2, wherein, The first polyol is a propylene oxide-ethylene oxide block copolymer.

5. The polyol composition of claim 1 or claim 2, wherein, The number average molecular weight of the first polyol is 4100 or more.

6. The polyol composition of claim 1 or claim 2, wherein, The content ratio of the first polyol is 16% by mass or more and 24% by mass or less relative to the total amount of the first polyol, the second polyol, and the third polyol. The content ratio of the first polyol is 16% by mass or more and 24% by mass or less, The content ratio of the second polyol is 16% by mass or more and 24% by mass or less, The content ratio of the third polyol is 55% by mass or more and 65% by mass or less.

7. The polyol composition according to claim 1 or claim 2, which is used for the production of a polyurethane foam.

8. A polyol composition having an average number of functional groups of 1.5 or more and 4.5 or less, The polyol composition has a hydroxyl value of 80 mgKOH / g or more and 120 mgKOH / g or less, The polyol composition has a content ratio of oxyalkylene units of 15.0% by mass or more and 17.3% by mass or less relative to the total amount of oxyalkylene units of the polyol composition.

9. An urethane foam composition which is an urethane foam composition containing a polyol component and a polyisocyanate component, The polyol component contains the polyol composition according to claim 1.

10. A polyurethane foam which is obtained by reacting the urethane foam composition according to claim 9, The urethane foam composition contains a polyol component and a polyisocyanate component, The polyol component contains the polyol composition according to claim 9, The polyurethane foam has at least one glass transition temperature in each of a temperature range of -70°C to -30°C and a temperature range of 0°C to 60°C, When the glass transition temperature is expressed in the form of a peak value of tan δ measured by dynamic viscoelasticity measurement at a vibration frequency of 10 Hz, The peak value of tan δ in -70°C to -30°C is 0.10 or less, The peak value of tan δ in 0°C to 60°C is 0.30 or more, The value of tan δ at -25°C is 0.095 or more. The peak value of tan δ in -70°C to -30°C is 0.07 or less, 11. The polyurethane foam of claim 10, wherein, The value of tan δ at -25°C is 0.10 or more. The polyisocyanate component contains at least one polyisocyanate compound selected from the group consisting of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate.

12. The polyurethane foam of claim 10 or claim 11, wherein, The urethane foam composition has an isocyanate index ([isocyanate group in the urethane foam composition / active hydrogen group in the urethane foam composition] x 100) of 50 or more and 200 or less.

13. The polyurethane foam of claim 10 or claim 11, wherein, 14. A molded article comprising the polyurethane foam according to claim 10 or claim 11.

15. The molded article according to claim 14, which is a cushion or a mattress. ​

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