Polyol composition

Abstract

To provide a polyol composition that can yield highly flame-retardant polyurethane foam while preventing the occurrence of caking.SOLUTION: The present invention provides a polyol composition that is reacted with polyisocyanate to yield polyurethane foam, the polyol composition containing a polyol, a foamer, a catalyst, a solid flame retardant, and a filler with an aspect ratio of 3 or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a polyol composition for reacting with polyisocyanate to obtain polyurethane foam. [Background technology]

[0002] Polyurethane foam, with its excellent thermal insulation properties, is used in practical applications for insulating and preventing condensation in various structures such as ceilings, roofs, and walls of buildings including apartment complexes, detached houses, and commercial buildings. Polyurethane foam is formed, for example, by spraying a urethane resin composition containing a polyol composition and polyisocyanate onto the surface of each structure, followed by foaming and curing.

[0003] From the viewpoint of improving the flame retardancy of polyurethane foam, it is known that solid flame retardants such as red phosphorus are included in the polyol composition used as a raw material. For example, Patent Document 1 describes an invention relating to a rigid polyurethane foam having high flame retardancy, which is composed of a reaction product between a polyol composition containing a polyol, a foam stabilizer, a catalyst, a blowing agent, and a flame retardant, and an isocyanate composition, and it describes the use of a solid flame retardant such as red phosphorus as the flame retardant. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2019-214651 [Overview of the project] [Problems that the invention aims to solve]

[0005] As mentioned above, including a solid flame retardant in a polyol composition tends to improve the flame retardancy of the resulting polyurethane foam. However, solid flame retardants dispersed in a liquid polyol composition can settle over time during storage, leading to a problem called caking, where they cannot be redispersed. When caking occurs in a polyol composition, the solid flame retardant does not disperse properly within the foam when it is mixed with polyisocyanate and foamed to form polyurethane foam, thus failing to improve flame retardancy. Therefore, the present invention aims to provide a polyol composition that can suppress the occurrence of caking and produce a polyurethane foam with excellent flame retardancy. [Means for solving the problem]

[0006] As a result of diligent research, the inventors have found that the above problems can be solved by a polyol composition containing a polyol, a blowing agent, a catalyst, a solid flame retardant, and a filler with an aspect ratio of 3 or more, and have completed the present invention. That is, the present invention provides the following [1] to

[10] .

[0007] [1] A polyol composition for obtaining a polyurethane foam by reacting with a polyisocyanate, comprising a polyol, a blowing agent, a catalyst, a solid flame retardant, and a filler having an aspect ratio of 3 or more. [2] The polyol composition according to [1] above, further containing metal oxide fine particles. [3] The polyol composition according to [1] or [2] above, wherein the catalyst comprises a trimerizing catalyst. [4] The polyol composition according to [3] above, wherein the trimerizing catalyst comprises a quaternary ammonium salt. [5] The polyol composition according to any one of [1] to [4] above, wherein the catalyst comprises an imidazole derivative. [6] The polyol composition according to any one of [1] to [5] above, wherein the catalyst comprises at least one metal catalyst selected from the group consisting of bismuth and tin. [7] The polyol composition according to any one of [1] to [6] above, wherein the solid flame retardant is a red phosphorus-based flame retardant. [8] A urethane resin composition comprising the polyol composition described in any of [1] to [7] above and a polyisocyanate. [9] The urethane resin composition according to [8] above, wherein the isocyanate index is 200 or higher.

[10] The urethane resin composition described in [9] above, for spraying. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a polyol composition that can suppress the occurrence of caking and produce a polyurethane foam with excellent flame retardancy. [Modes for carrying out the invention]

[0009] The polyol composition of the present invention is a polyol composition for obtaining polyurethane foam by reacting with polyisocyanate, and contains a polyol, a blowing agent, a catalyst, a solid flame retardant, and a filler with an aspect ratio of 3 or more.

[0010] [Polyol composition] The polyol composition of the present invention contains a polyol, a blowing agent, a catalyst, a solid flame retardant, and a filler with an aspect ratio of 3 or higher. Each component will be described in detail below.

[0011] <Filler> The polyol composition of the present invention contains a filler with an aspect ratio of 3 or more. By containing a filler with an aspect ratio of 3 or more, aggregation of the solid flame retardant contained in the polyol composition is suppressed, thereby suppressing the occurrence of caking. On the other hand, if the aspect ratio of the filler is less than 3, it becomes difficult to suppress caking. From the perspective of suppressing the occurrence of caking of the polyol composition, the aspect ratio of the filler is preferably 5 or more, more preferably 10 or more, still more preferably 15 or more, and preferably 30 or less, more preferably 20 or less.

[0012] The aspect ratio of the filler is the ratio of the maximum length to the minimum length of the filler (maximum length / minimum length). The minimum length is the length in the direction perpendicular to the maximum length. For example, when the shape of the filler is needle-like, the aspect ratio is the ratio of the length to the diameter of the filler (length / diameter). When the shape of the filler is plate-like, the aspect ratio is the ratio of the maximum length to the thickness of the filler (maximum length / thickness). The aspect ratio may be determined as an average value by observing a sufficient number (for example, 250) of fillers with a scanning electron microscope.

[0013] The filler in the present invention is a compound other than the solid flame retardant described later, and its type is not particularly limited, but from the perspective of improving the flame retardancy of the polyurethane foam, it is preferably an inorganic filler. The shape of the filler is not particularly limited, and it may be a needle-like filler, a plate-like filler, or other shapes, but from the perspective of easily suppressing the occurrence of caking, it is preferably a needle-like filler. The average particle size of the filler is not particularly limited, but from the perspective of suppressing the occurrence of caking, it is preferably 0.1 to 100 μm, more preferably 1 to 50 μm, still more preferably 5 to 20 μm. The average particle size is a value measured by the laser diffraction method.

[0014] Examples of the needle-like filler include wollastonite (wollastonite), basic magnesium sulfate, aluminum borate, xonotlite, dowsonite, elesite, boehmite, rod-shaped hydroxyapatite, potassium titanate whisker, aluminum borate whisker, magnesium-based whisker, silicon-based whisker, needle-like alumina, needle-like ceramic, asbestos, needle-like calcium carbonate, gypsum fiber, glass fiber, asbestos fiber, silica fiber, alumina fiber, silica-alumina fiber, zirconia fiber, carbon fiber, graphite fiber, boron nitride fiber, boron fiber, metal fiber, and the like. Among these, wollastonite is particularly preferred.

[0015] The content of the filler in the polyol composition is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, and still more preferably 1.5 to 15 parts by mass with respect to 100 parts by mass of the polyol. When the content of the filler is not less than these lower limit values, it becomes easy to suppress the occurrence of caking during storage of the polyol composition. When the content of the filler is not more than these upper limit values, the viscosity of the polyol composition can be adjusted to a certain level or lower, and it becomes easy to appropriately form a polyurethane foam using a spraying device or the like.

[0016] The mass ratio of the filler to the solid flame retardant in the polyol composition (mass ratio of filler / mass of solid flame retardant) is preferably 0.01 to 1, more preferably 0.02 to 0.5, and still more preferably 0.05 to 0.3. When the mass ratio of the filler to the solid flame retardant is not less than these lower limit values, it becomes easy to suppress the occurrence of caking during storage of the polyol composition. When the mass ratio of the filler to the solid flame retardant is not more than these upper limit values, the viscosity of the polyol composition can be adjusted to a certain level or lower, and it becomes easy to appropriately form a polyurethane foam using a spraying device or the like.

[0017] <Metal oxide fine particles> The polyol composition of the present invention preferably contains metal oxide fine particles. The metal oxide fine particles function as a thickening agent for the polyol composition. By using the above-mentioned filler with an aspect ratio of 3 or more in combination with metal oxide fine particles, the settling of the solid flame retardant can be more easily suppressed, and caking can be effectively prevented. Metal oxide nanoparticles are those in which the metallic portion is, for example, aluminum, titanium, zirconium, or silicon. Specific examples of metal oxide nanoparticles include aluminum oxide, titanium oxide, zirconium oxide, and silicon oxide, with silicon oxide being the preferred metal oxide nanoparticle. The average primary particle size of the metal oxide nanoparticles is preferably 3 nm to 60 nm, more preferably 5 nm to 50 nm, and even more preferably 5 nm to 40 nm. The average primary particle size is best measured using a transmission electron microscope. The metal oxide nanoparticles may be surface-treated or untreated.

[0018] The amount of metal oxide fine particles blended is preferably in the range of 0.5 to 8 parts by mass, more preferably in the range of 0.8 to 6 parts by mass, and even more preferably in the range of 1 to 5 parts by mass, per 100 parts by mass of the polyol compound. By setting the amount of metal oxide fine particles above the lower limit, caking can be effectively suppressed, and by setting it below the upper limit, the viscosity of the polyol composition can be kept below a certain level, making it easier to form polyurethane foam.

[0019] <Solid flame retardant> The polyol composition of the present invention contains a solid flame retardant. The inclusion of a solid flame retardant in the polyol composition improves the flame retardancy of the resulting polyurethane foam. Here, a solid flame retardant is a flame retardant that is solid at room temperature (25°C) and normal pressure (1 atmosphere). By using a solid flame retardant, the flame retardancy of polyurethane foam is improved, and deformation when exposed to heat is more easily suppressed. Examples of solid flame retardants include red phosphorus-based flame retardants, boron-based flame retardants, bromine-containing flame retardants, phosphate-containing flame retardants, antimony-containing flame retardants, phosphinic acid-based flame retardants, and metal hydroxide-based flame retardants. Among these, red phosphorus-based flame retardants are preferred as solid flame retardants. From the viewpoint of improving flame retardancy, one type of solid flame retardant may be used alone, or two or more types may be used in combination.

[0020] (Red phosphorus-based flame retardant) Red phosphorus-based flame retardants may be red phosphorus alone, red phosphorus coated with a resin, metal hydroxide, metal oxide, etc., or a mixture of red phosphorus and a resin, metal hydroxide, metal oxide, etc. The resin used to coat or mix with red phosphorus is not particularly limited, but examples include thermosetting resins such as phenolic resins, epoxy resins, unsaturated polyester resins, melamine resins, urea resins, aniline resins, and silicone resins. From the viewpoint of flame retardancy, metal hydroxides are preferred as the compound to be coated or mixed. The metal hydroxides described later may be appropriately selected and used.

[0021] (Boron-based flame retardant) Examples of boron-based flame retardants include alkali metal borates such as lithium borate, sodium borate, potassium borate, and cesium borate; alkaline earth metal borates such as magnesium borate, calcium borate, and barium borate; zirconium borate, zinc borate, aluminum borate, and ammonium borate. Among these, zinc borate is preferred.

[0022] (Bromine-based flame retardant) Brominated flame retardants are not particularly limited as long as they are compounds that contain bromine in their molecular structure, but examples include aromatic brominated compounds. Specific examples of the aromatic brominated compounds include, for example, monomer-based organic bromine compounds such as hexabromobenzene, pentabromotoluene, hexabromobiphenyl, decabromobiphenyl, hexabromocyclodecane, decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, bis(pentabromphenoxy)ethane, ethylenebis(pentabromophenyl), ethylenebis(tetrabromophthalimide), and tetrabromobisphenol A, as well as polycarbonate oligomers produced using brominated bisphenol A as a raw material, and the polycarbonate oligomer and bisphenol A. Examples include brominated polycarbonates such as copolymers of the following, diexo compounds produced by the reaction of brominated bisphenol A and epichlorohydrin, monoepoxy compounds obtained by the reaction of brominated phenols and epichlorohydrin, halogenated brominated compound polymers such as poly(brominated benzyl acrylate), brominated polyphenylene ether, brominated bisphenol A, cyanur chloride and brominated phenol condensates, brominated polystyrene such as brominated (polystyrene), poly(brominated styrene), and crosslinked brominated polystyrene, and crosslinked or non-crosslinked brominated poly(α-methylstyrene). Among these, ethylenebis(pentabromophenyl), ethylenebis(tetrabromophthalimide), and hexabromobenzene are preferred.

[0023] (Phosphate-containing flame retardant) Examples of phosphate-containing flame retardants include phosphates comprising a salt of phosphoric acid with at least one metal or compound selected from metals of groups IA to IVB of the periodic table, ammonia, aliphatic amines, and aromatic amines. While there are no specific limitations on the type of phosphoric acid, various types of phosphoric acids can be mentioned, such as monophosphate, pyrophosphate, and polyphosphate. Examples of metals from groups IA to IVB of the periodic table include lithium, sodium, calcium, barium, iron(II), iron(III), and aluminum. Examples of aliphatic amines include methylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, and piperazine. Examples of aromatic amines include pyridine, triazine, and melamine. Furthermore, the above-mentioned phosphate-containing flame retardants may be subjected to known water-resistance-improving treatments, such as silane coupling agent treatment or coating with melamine resin.

[0024] Specific examples of phosphate-containing flame retardants include monophosphates, pyrophosphates, and polyphosphates. The monophosphates are not particularly limited, but examples include ammonium salts such as ammonium phosphate, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate; sodium salts such as monosodium phosphate, disodium phosphate, trisodium phosphate, monosodium phosphite, disodium phosphite, and sodium hypophosphite; potassium salts such as monopotassium phosphate, dipotassium phosphate, tripotassium phosphate, monopotassium phosphite, dipotassium phosphite, and potassium hypophosphite; lithium salts such as monolithium phosphate, dilithium phosphate, trilithium phosphate, monolithium phosphite, dilithium phosphite, and lithium hypophosphite; barium salts such as barium dihydrogen phosphate, barium hydrogen phosphate, tribarium phosphate, and barium hypophosphite; magnesium salts such as magnesium monohydrogen phosphate, magnesium hydrogen phosphate, trimagnesium phosphate, and magnesium hypophosphite; calcium salts such as calcium dihydrogen phosphate, calcium hydrogen phosphate, tricalcium phosphate, and calcium hypophosphite; and zinc salts such as zinc phosphate, zinc phosphite, and zinc hypophosphite.

[0025] Polyphosphates are not particularly limited, but examples include ammonium polyphosphate, piperazine polyphosphate, melamine polyphosphate, ammonium polyphosphate amide, and aluminum polyphosphate. Among these, the use of monophosphate is preferable because it improves the self-extinguishing properties of the phosphate-containing flame retardant, and the use of ammonium dihydrogen phosphate is even more preferable. A single phosphate-containing flame retardant may be used, or two or more types may be used together.

[0026] (Antimony-containing flame retardant) Examples of antimony-containing flame retardants used in the present invention include antimony oxide, antimony salts, and pyroantimony salts. Examples of antimony oxides include antimony trioxide and antimony pentoxide. Examples of antimonate salts include sodium antimonate and potassium antimonate. Examples of pyroantimonate salts include sodium pyroantimonate and potassium pyroantimonate. The antimony-containing flame retardant is preferably antimony oxide. Antimony-containing flame retardants may be used individually or in combination of two or more types.

[0027] (Phosphinic acid-based flame retardant) Examples of phosphinic acid-based flame retardants include phosphinic acid, dimethylphosphinic acid, methylethylphosphinic acid, methylpropylphosphinic acid, diethylphosphinic acid, dioctylphosphinic acid, phenylphosphinic acid, diethylphenylphosphinic acid, diphenylphosphinic acid, and bis(4-methoxyphenyl)phosphinic acid.

[0028] (Metal hydroxide-based flame retardant) Examples of metal hydroxide-based flame retardants include magnesium hydroxide, calcium hydroxide, aluminum hydroxide, iron hydroxide, nickel hydroxide, zirconium hydroxide, titanium hydroxide, zinc hydroxide, copper hydroxide, vanadium hydroxide, and tin hydroxide. Metal hydroxide-based flame retardants may be used individually or in combination of two or more types.

[0029] The amount of solid flame retardant is preferably 5 to 100 parts by mass, more preferably 10 to 80 parts by mass, and even more preferably 20 to 50 parts by mass, per 100 parts by mass of polyol, from the viewpoint of improving flame retardancy and adjusting viscosity to a low level.

[0030] <Liquid Flame Retardant> In addition to the solid flame retardant described above, a liquid flame retardant may also be used as the flame retardant contained in the polyol composition of the present invention. A liquid flame retardant is one that becomes liquid at room temperature (25°C) and normal pressure (1 atm). While there are no particular limitations on the liquid flame retardant, a phosphate ester-based flame retardant is preferred.

[0031] As phosphate ester-based flame retardants, monophosphate esters, condensed phosphate esters, etc., can be used. A monophosphate ester is a phosphate ester that has one phosphorus atom in its molecule. Examples of monophosphate esters include trialkyl phosphates such as trimethyl phosphate, triethyl phosphate, tributyl phosphate, and tri(2-ethylhexyl) phosphate; halogen-containing phosphate esters such as tris(β-chloropropyl) phosphate; trialkoxy phosphates such as tributoxyethyl phosphate; aromatic ring-containing phosphate esters such as tricresyl phosphate, trixylenyl phosphate, tris(isopropylphenyl) phosphate, cresyldiphenyl phosphate, and diphenyl(2-ethylhexyl) phosphate; and acidic phosphate esters such as monoisodecyl phosphate and diisodecyl phosphate.

[0032] Examples of condensed phosphate esters include aromatic condensed phosphate esters such as trialkyl polyphosphates, resorcinol polyphenyl phosphates, bisphenol A polycresyl phosphates, and bisphenol A polyphenyl phosphates. Examples of commercially available condensed phosphate esters include "CR-733S," "CR-741," and "CR747" from Daihachi Chemical Industry Co., Ltd., and "ADEKA Stab PFR" and "FP-600" from ADEKA Corporation.

[0033] The phosphate ester flame retardants may be used individually from the above-mentioned types, or two or more may be used in combination. Among these, monophosphate esters are preferred from the viewpoint of making it easier to adjust the viscosity of the polyol composition and improving the flame retardancy of the polyurethane foam, and halogen-containing phosphate esters such as tris(β-chloropropyl) phosphate are more preferred.

[0034] The content of the liquid flame retardant in the polyol composition is not particularly limited, but is preferably 15 to 90 parts by mass, more preferably 20 to 80 parts by mass, and even more preferably 25 to 70 parts by mass, per 100 parts by mass of polyol. When the content of the liquid flame retardant is above these lower limits, it becomes easier to impart flame retardancy to the polyurethane foam without making the viscosity of the polyol composition too high or adding too much powder such as solid flame retardant. Furthermore, when the content of the liquid flame retardant is below these upper limits, foaming is not inhibited, making it easier to manufacture the polyurethane foam.

[0035] <Polyol> The polyol composition of the present invention contains a polyol. Examples of polyols include polylactone polyols, polycarbonate polyols, polyester polyols, polymer polyols, and polyether polyols.

[0036] Examples of polylactone polyols include polypropiolactone glycol, polycaprolactone glycol, and polyvalerolactone glycol. Examples of polycarbonate polyols include polyols obtained by the de-alcoholization reaction of hydroxyl group-containing compounds such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, octanediol, and nonanediol with ethylene carbonate, propylene carbonate, etc.

[0037] Examples of polyester polyols include polymers obtained by dehydrating and condensing a polybasic acid and a polyhydric alcohol, and condensates of hydroxycarboxylic acids and the aforementioned polyhydric alcohols. Examples of polybasic acids include adipic acid, azelaic acid, sebacic acid, isophthalic acid (m-phthalic acid), terephthalic acid (p-phthalic acid), o-phthalic acid (phthalic acid), naphthalenedicarboxylic acid, and succinic acid. Examples of polyhydric alcohols include bisphenol A, ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, diethylene glycol, 1,6-hexane glycol, and neopentyl glycol. Examples of hydroxycarboxylic acids include castor oil and reaction products of castor oil and ethylene glycol.

[0038] Examples of polymer polyols include polymers obtained by graft polymerization of ethylenically unsaturated compounds such as acrylonitrile, styrene, methyl acrylate, and methacrylate onto aromatic polyols, alicyclic polyols, aliphatic polyols, and polyester polyols, as well as polybutadiene polyols, or hydrogenated versions thereof.

[0039] Examples of polyether polyols include polymers obtained by ring-opening polymerization of at least one C2-C6 alkylene oxide, specifically ethylene oxide, propylene oxide, or tetrahydrofuran, in the presence of at least one low molecular weight active hydrogen compound having two or more active hydrogen atoms, such as a polyhydric alcohol. Examples of alkylene oxides include at least one of ethylene oxide and propylene oxide. Examples of low molecular weight active hydrogen compounds having two or more active hydrogen atoms include bisphenol A, ethylene glycol, propylene glycol, butylene glycol, diols such as 1,6-hexanediol, triols such as glycerin and trimethylolpropane, tetrahydric to octahydric alcohols such as pentaerythritol, sorbitol, mannitol, sorbitan, diglycerin, dipentaerythritol, sucrose, glucose, mannose, fructose, methyl glucoside and its derivatives, phloroglucinol, and cresol. Examples include polyols such as pyrogallol, catechol, hydroquinone, bisphenol A, bisphenol F, bisphenol S, 1,3,6,8-tetrahydroxynaphthalene, and 1,4,5,8-tetrahydroxyanthracene; castor oil polyols; (co)polymers of hydroxyalkyl (meth)acrylates; polyfunctional polyols (e.g., 2 to 100 functional groups) such as polyvinyl alcohol; condensates of phenol and formaldehyde (novolac); amines such as ethylenediamine and butylenediamine. As the polyether polyol, a Mannich-type polyether polyol may be used. A Mannich-type polyether polyol is obtained using the Mannich reaction and is a Mannich condensate having two or more hydroxyl groups in the molecule, or a polyether polyol obtained by adding an alkylene oxide to such a Mannich condensate.

[0040] Polyols used in the present invention are preferably polyester polyols and polyether polyols. Polyols having two hydroxyl groups are also preferred. Among these, aromatic polyester polyols, which are polyester polyols having an aromatic ring, are preferred from the viewpoint of improving the flame retardancy of polyurethane foam. The aromatic polyester polyol is preferably a condensate of an aromatic dicarboxylic acid such as o-phthalic acid (phthalic acid), m-phthalic acid (isophthalic acid), p-phthalic acid (terephthalic acid), or naphthalenedicarboxylic acid with a glycol. From the viewpoint of improving the flame retardancy of the polyurethane foam, particularly its ability to prevent flame spread, the aromatic polyester polyol is more preferably a phthalic acid-based polyester polyol, which is a condensate of phthalic acid and glycol. In particular, the aromatic polyester polyol is even more preferably a condensate of at least one selected from p-phthalic acid-based polyester polyol, which is a condensate of p-phthalic acid and glycol, and o-phthalic acid-based polyester polyol, which is a condensate of o-phthalic acid and glycol.

[0041] When the polyol contains an aromatic polyester polyol, the amount is not particularly limited, but is preferably 50 parts by mass or more, more preferably 70 parts by mass or more, even more preferably 80 parts by mass or more, and even more preferably 100 parts by mass, per 100 parts by mass of the polyol.

[0042] The weighted average hydroxyl value of the polyol is preferably 20 to 350 mg KOH / g, more preferably 50 to 300 mg KOH / g, and even more preferably 100 to 280 mg KOH / g. When the hydroxyl value of the polyol is below the upper limit, the viscosity of the polyol composition tends to decrease, which is preferable from the viewpoint of handling and other factors. On the other hand, when the hydroxyl value of the polyol is above the lower limit, the crosslinking density of the polyurethane foam increases, resulting in higher strength and better workability during spraying. The hydroxyl value of polyols can be measured according to JIS K 1557-1:2007.

[0043] Here, the weighted average hydroxyl value of a polyol is determined by the sum of the products of the hydroxyl values ​​of the individual polyols constituting the polyol and the weight fraction of each individual polyol in the polyol. For example, when using two types of polyols, (d1) and (d2), if the hydroxyl value of polyol (d1) is X1 and the amount added is m1, and the hydroxyl value of polyol (d2) is X2 and the amount added is m2, the weighted average hydroxyl value is expressed by the following formula. Note that the amounts m1 and m2 are parts by mass in 100 parts by mass of polyol. Weighted average hydroxyl value (mgKOH / g)=X1×(m1 / (m1+m2))+X2×(m2 / (m1+m2))

[0044] <Foaming agent> The polyol composition of the present invention contains a blowing agent. Specific examples of blowing agents include, for example, water, low-boiling hydrocarbons, chlorinated aliphatic hydrocarbon compounds, fluorine compounds, hydrochlorofluorocarbon compounds, hydrofluorocarbons, ether compounds, and hydrofluoroolefins. Furthermore, examples of blowing agents include organic physical blowing agents such as mixtures of these compounds, and inorganic physical blowing agents such as nitrogen gas, oxygen gas, argon gas, and carbon dioxide gas. Examples of the low-boiling hydrocarbons mentioned above include propane, butane, pentane, hexane, heptane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, and cycloheptane. Examples of the above-mentioned chlorinated aliphatic hydrocarbon compounds include dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, and isopentyl chloride. Examples of the fluorine compounds mentioned above include CHF3, CH2F2, and CH3F. Examples of the above-mentioned hydrochlorofluorocarbon compounds include trichloromonofluoromethane, trichlorotrifluoroethane, and dichloromonofluoroethane (e.g., HCFC141b (1,1-dichloro-1-fluoroethane), HCFC22 (chlorodifluoromethane), HCFC142b (1-chloro-1,1-difluoroethane)). Examples of the above-mentioned hydrofluorocarbons include HFC-245fa (1,1,1,3,3-pentafluoropropane) and HFC-365mfc (1,1,1,3,3-pentafluorobutane). Examples of the ether compounds mentioned above include diisopropyl ether. Examples of the above-mentioned hydrofluoroolefins include HFO-1233zd(E) (trans-1-chloro-3,3,3-trifluoropropene), HFO-1234yf (2,3,3,3-tetrafluoro-1-propene), HFO-1336mzz(Z) (cis-1,1,1,4,4,4-hexafluorobuta-2-ene), and HFO-1224yd(Z).

[0045] Among the above, hydrofluoroolefins and water are preferred as foaming agents, and it is preferable to use hydrofluoroolefins and water in combination. As the water used as a foaming agent, for example, ion-exchanged water, distilled water, etc. can be used as appropriate.

[0046] The amount of foaming agent is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, and even more preferably 20 to 35 parts by mass, per 100 parts by mass of polyol, from the viewpoint of density adjustment. When using hydrofluoroolefin as a foaming agent, the hydrofluoroolefin content is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, and even more preferably 20 to 35 parts by mass, per 100 parts by mass of polyol. When water is used as a foaming agent, the water content is preferably 0.1 to 5 parts by mass, more preferably 0.1 to 2.5 parts by mass, and even more preferably 0.5 to 2 parts by mass, per 100 parts by mass of polyol.

[0047] <Catalyst> The polyol composition of the present invention contains a catalyst. The catalyst may contain a trimerizing catalyst, a resinification catalyst, or both a trimerizing catalyst and a resinification catalyst. In particular, it is preferable that the catalyst contains both a trimerizing catalyst and a resinification catalyst.

[0048] (Resin-based catalyst) The resin catalyst preferably contains a metal catalyst (resin-based metal catalyst). The presence of the metal catalyst promotes the reaction between the polyol and the polyisocyanate. From the viewpoint of foaming properties, the catalyst in the present invention preferably contains at least one metal catalyst selected from the group consisting of bismuth and tin, and more preferably contains bismuth.

[0049] The above metal catalyst is preferably a metal salt selected from bismuth salts and tin salts, and more preferably a bismuth salt. The metal salt is preferably an organic acid metal salt, and more preferably a metal salt of a carboxylic acid having 5 or more carbon atoms. Having 5 or more carbon atoms in the carboxylic acid provides good stability against blowing agents, especially hydrofluoroolefins. Furthermore, from the viewpoint of catalytic activity, the number of carbon atoms in the carboxylic acid is preferably 18 or less, and more preferably 12 or less. The carboxylic acid is preferably an aliphatic carboxylic acid, and more preferably a saturated aliphatic carboxylic acid. The carboxylic acid may be linear or have a branched structure, but it is preferable to have a branched structure. Specific examples of carboxylic acids include octyl acid, lauryl acid, versatic acid, pentanoic acid, and acetic acid, with octyl acid being preferred among these. In other words, the transition metal salt is preferably a metal salt of octyl acid. These carboxylic acids may be linear as described above, but they may also have a branched structure. An example of octyl acid having a branched structure is 2-ethylhexanoic acid. Preferred metal salts of carboxylic acids include bismuth salts and tin salts of carboxylic acids, with bismuth salts of octic acid being particularly preferred. Alternatively, the metal salt of the carboxylic acid may be an alkyl metal carboxylic acid salt. For example, the tin salt of the carboxylic acid may be a dialkyltin carboxylic acid salt, and preferably a dioctyltin carboxylic acid salt. Specific examples of metal salts of carboxylic acids include bismastrioctate, dioctyl tin versatate, dibutyl tin dilaurate, dioctyl tin dilaurate, and tin dioctylate, with bismastrioctate and dioctyl tin versatate being preferred, and bismastrioctate being more preferred.

[0050] The content of the above metal catalyst is not particularly limited, but is preferably 0.1 to 10 parts by mass, more preferably 0.3 to 5 parts by mass, and even more preferably 0.5 to 2 parts by mass per 100 parts by mass of polyol.

[0051] The catalyst used in the polyol composition of the present invention more preferably contains an imidazole derivative, which is a resinification amine catalyst, as the resinification catalyst. Imidazole derivatives are less affected by hydrofluoroolefins and facilitate the reaction between polyols and polyisocyanates. Therefore, by including imidazole derivatives in addition to the metal catalysts mentioned above, the reactivity between the polyol and polyisocyanate is enhanced, resulting in even better foaming properties. The imidazole derivative is preferably imidazole substituted at the 1-position and 2-positions independently with alkyl groups having 8 or fewer carbon atoms, and the alkyl groups preferably have 6 or fewer carbon atoms, more preferably 4 or fewer carbon atoms. Preferred specific examples of the imidazole derivative are represented by the following general formula (1).

[0052] [Chemical formula] (In general formula (1), R 1 and R 2 each independently represent an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms.)

[0053] R 1 and R 2 in general formula (1) each independently represent an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms. The alkyl group and the alkenyl group may each be linear or may have a branched structure. Specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a hexyl group, a heptyl group, an octyl group, and the like. Specific examples of the alkenyl group include a vinyl group, a 1-propenyl group, an allyl group, an isopropenyl group, a 1-butenyl group, a 2-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, and the like. R 1 and R 2 When the number of carbon atoms of the alkyl group or alkenyl group is at least the lower limit value, the steric hindrance becomes large and it is less likely to be affected by a blowing agent such as a hydrofluoroolefin, which is preferable. On the other hand, when the number of carbon atoms of the alkyl group of R 1 and R 2 is at most the upper limit value, the steric hindrance does not become extremely large, so that the reaction between the polyol and the polyisocyanate can proceed rapidly and the foaming property also becomes good. From these viewpoints, R 1 and R 2Each of these groups is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms, and even more preferably a methyl group.

[0054] Examples of imidazole derivatives represented by general formula (1) include 1,2-dimethylimidazole, 1-ethyl-2-methylimidazole, 1-methyl-2-ethylimidazole, 1,2-diethylimidazole, and 1-isobutyl-2-methylimidazole. Among these, 1,2-dimethylimidazole and 1-isobutyl-2-methylimidazole are preferred from the viewpoint of improving catalyst activity in the presence of hydrofluoroolefins and promoting rapid reaction. Furthermore, 1,2-dimethylimidazole is even more preferred from the viewpoint of further enhancing stability.

[0055] The content of the imidazole derivative in the polyol composition is preferably 0.1 to 15 parts by mass, more preferably 0.5 to 10 parts by mass, and even more preferably 1.5 to 7 parts by mass, per 100 parts by mass of polyol. When the content of the imidazole derivative is above the lower limit, urethane bonds are more likely to form, the reaction proceeds rapidly, and foaming properties are good. On the other hand, when the content of the imidazole derivative is below the upper limit, the reaction rate is easier to control, which is preferable.

[0056] The content of the resinification catalyst in the polyol composition is preferably 0.2 to 25 parts by mass, more preferably 0.8 to 15 parts by mass, and even more preferably 3 to 20 parts by mass, per 100 parts by mass of polyol.

[0057] (trimerization catalyst) The catalyst included in the polyol composition of the present invention preferably contains a trimerizing catalyst. The trimerizing catalyst is a catalyst that reacts with the isocyanate groups contained in the polyisocyanate to trimerize them and promote the formation of an isocyanurate ring. The advantage of including a trimerizing catalyst is that a good polyurethane foam can be obtained by completing the reaction of unreacted isocyanate groups. Examples of trimerizing catalysts include metal catalysts and ammonium salts. Among these, the trimerizing catalyst preferably contains an ammonium salt, and more preferably contains a quaternary ammonium salt. Examples of metal catalysts used as trimerization catalysts (trimerization metal catalysts) include potassium organic acids, preferably potassium octoates such as potassium 2-ethylhexanoate, potassium acetate, potassium propionate, potassium butanoate, potassium benzoate, and other potassium carboxylates having 2 to 8 carbon atoms. As the ammonium salt, tertiary ammonium salts such as triethylammonium salt and triphenylammonium salt, and quaternary ammonium salts such as tetramethylammonium salt, tetraethylammonium salt, and tetraphenylammonium salt can be used, but among these, quaternary ammonium salts are preferred. The ammonium salt is, for example, an ammonium salt of a carboxylic acid. Examples of carboxylic acids in the ammonium salt include saturated fatty acids having 1 to 10 carbon atoms, preferably 2 to 8 carbon atoms. The hydrocarbon group of the saturated fatty acid may be linear or branched, but branching is preferred. Specific examples of carboxylic acids include 2-ethylhexanoic acid, 2,2-dimethylpropanoic acid, acetic acid, and formic acid, but among these, 2,2-dimethylpropanoic acid is preferred. The trimerization catalyst may be used alone or two or more may be used in combination.

[0058] The content of the trimerizing catalyst in the polyol composition is preferably 0.1 to 15 parts by mass, more preferably 1 to 12 parts by mass, and even more preferably 2 to 10 parts by mass, per 100 parts by mass of the polyol compound.

[0059] <Foam stabilizer> The polyol composition of the present invention may contain a foam stabilizer. Suitable foam stabilizers include compounds having polar and non-polar portions within their molecule and exhibiting surfactant properties. The foam stabilizer is not particularly limited, but examples include surfactants such as polyoxyalkylene foam stabilizers like polyoxyalkylene alkyl ethers and silicone foam stabilizers like organopolysiloxanes. As a silicone foam stabilizer, a graft copolymer of polyoxyalkylene glycol, which is a polymer of ethylene oxide or propylene oxide, and polydimethylsiloxane may also be used. Commercially available products can also be used, specifically foam stabilizers such as SH-193 (manufactured by Toray Dow Corning), B8467 (manufactured by Evonik), F501 (manufactured by Shin-Etsu Chemical Co., Ltd.), and SF-2937F (manufactured by Dow Toray). The foam stabilizer content is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 3 parts by mass or less, per 100 parts by mass of polyol. When the foam stabilizer content is below these upper limits, the surface condition of the polyurethane foam improves, and the adhesion between the polyurethane foam and the inorganic coating is more easily improved. The foam stabilizer content is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 1 part by mass or more, per 100 parts by mass of polyol. When the foam stabilizer content is above these lower limits, the stability of foaming tends to improve.

[0060] (Other ingredients) The polyol composition in the present invention may, as necessary and without impairing the objectives of the present invention, contain one or more antioxidants such as phenolic, amine, and sulfur-based antioxidants, heat stabilizers, light stabilizers, metal damage inhibitors, antistatic agents, stabilizers, crosslinking agents, lubricants, softeners, pigments, dyes, etc. There are no particular limitations on the method for producing the polyol composition of the present invention; for example, it can be produced by mixing each component.

[0061] <Polyisocyanate> The urethane resin composition in the present invention contains the above-mentioned polyol composition and polyisocyanate. As the polyisocyanate contained in the urethane resin composition, various polyisocyanate compounds such as aromatic, alicyclic, and aliphatic compounds having two or more isocyanate groups can be used. Preferably, liquid diphenylmethane diisocyanate (MDI) is used due to its ease of handling, rapid reaction, excellent physical properties of the resulting polyurethane foam, and low cost. Examples of liquid MDI include crude MDI (also called polymeric MDI). Specific commercially available liquid MDI products include "44V-10" and "44V-20" (manufactured by Sumika Covestro Urethane Co., Ltd.) and "Millionate MR-200" (Nippon Polyurethane Industry Co., Ltd.). Alternatively, uretonimine-containing MDI (for example, "Millionate MTL": manufactured by Nippon Polyurethane Industry Co., Ltd.) may also be used. Furthermore, a polyisocyanate compound may be treated in advance to increase its affinity with polyols by reacting some of the isocyanate active groups in the polyisocyanate compound with a hydroxyl group-containing compound. In addition to liquid MDI, other polyisocyanates may be used in combination, and any polyisocyanate known in the field of polyurethanes can be used without limitation.

[0062] The isocyanate index of the urethane resin composition of the present invention is preferably 150 or higher, more preferably 200 or higher, and even more preferably 250 or higher, from the viewpoint of properly forming polyurethane foam and imparting good flame retardancy. Furthermore, the isocyanate index of the urethane resin composition is preferably 800 or less, more preferably 600 or less, and even more preferably 500 or less. When the isocyanate index is below these upper limits, flame retardancy that is sufficiently commensurate with the manufacturing cost can be obtained. The isocyanate index (INDEX) is calculated using the following method.

[0063] INDEX = Equivalents of polyisocyanate ÷ (Equivalents of polyol + Equivalents of water) × 100 Here, Equivalent weight of polyisocyanate = Number of parts of polyisocyanate used × NCO content (%) × 100 / Molecular weight of NCO The equivalent weight of the polyol = OHV × the amount of polyol used ÷ the molecular weight of KOH, where OHV is the hydroxyl value of the polyol (mgKOH / g). Equivalent amount of water = Number of parts of water used × Number of OH groups in water / Molecular weight of water In the above formula, the unit of the number of parts used is weight (g), the molecular weight of the NCO group is 42, the NCO content is the proportion of NCO groups in the polyisocyanate compound expressed in mass%, and for the sake of unit conversion in the above formula, the molecular weight of KOH is assumed to be 56100, the molecular weight of water is assumed to be 18, and the number of OH groups in water is assumed to be 2.

[0064] <Polyurethane foam> The polyurethane foam in the present invention is formed from the above-described urethane resin composition, and more specifically, is obtained by foaming and curing the urethane resin composition. As described above, the polyurethane foam of the present invention is manufactured using a polyurethane composition in which caking is suppressed as a raw material, and therefore can exhibit good flame retardancy.

[0065] [Application] The polyol composition, urethane resin composition, and polyurethane foam formed from the present invention are not particularly limited in their uses, but can be used to fill cavities in structures such as buildings, furniture, automobiles, trains, and ships, or for spraying onto such structures. In particular, they are preferably used for spraying onto surfaces such as walls, ceilings, roofs, and floors, i.e., for spraying applications. Since the polyol composition of the present invention suppresses caking, when the composition is used for spraying applications, it mixes easily with polyisocyanate, resulting in good dispersibility of the solid flame retardant in the resulting polyurethane foam. Therefore, good flame retardancy is achieved. Spraying can be carried out using a spraying device (e.g., GRACO A-25) and a spray gun (e.g., Gasmar D-gun). Spraying is performed by temperature-controlled mixing of the polyol composition and polyisocyanate in separate containers within the spraying device, then causing them to collide and mix at the tip of the spray gun, and finally atomizing the mixture using air pressure. The spraying device and spray gun are well-known and commercially available. Furthermore, the stock temperature settings and pressure can be the same as those for general polyurethane foam spraying. [Examples]

[0066] The present invention will be described in more detail by reference to examples, but the present invention is not limited in any way by these examples.

[0067] The details of each component used in each example and comparative example are as follows. <Polyol> • p-phthalate-based polyester polyol (manufactured by Kawasaki Chemical Industries, Ltd., product name: Maximol RLK-087, hydroxyl value = 200 mg KOH / g)

[0068] <Catalyst> (1) Trimerization catalyst • Quaternary ammonium salt: tetramethylammonium 2,2-dimethylpropanoate (Evonik, product name: DABCO TMR7), concentration 45-55% by mass • Potassium 2-ethylhexanoate (Evonik, product name: DABCO K-15), concentration 70-80% by mass (2) Resin-based catalyst • Imidazole derivative 1,2-dimethylimidazole (manufactured by Kao Corporation, product name: Kaolizer No. 390), concentration 65-75% by mass • Bismuth-based catalyst: Bismuth 2-ethylhexanoate (manufactured by Nitto Chemical Co., Ltd., product name: Bi28), concentration 81-90% by mass

[0069] <Foaming agent> • Water with deionized water • HFO-1233zd <Hydrofluoroolefin> (Honeywell, product name: Solstice LBA)

[0070] <Liquid Flame Retardant> • Phosphate ester-based flame retardant: Tris(β-chloropropyl) phosphate (manufactured by Daihachi Chemical Co., Ltd., product name: TMCPP)

[0071] <Solid flame retardant> • Red phosphorus-based flame retardant (manufactured by Phosphorus Chemical Industry Co., Ltd., product name: Nova Excel 140)

[0072] <Filler> • Needle-shaped filler: Wollastonite (manufactured by Kinsei Matec Co., Ltd.: SH1250), aspect ratio 16, average particle size 9.5 μm • Needle-shaped filler: Wollastonite (manufactured by Kinsei Matec Co., Ltd.: FPW#400), aspect ratio 5, average particle size 12.3 μm • Needle-shaped filler: Wollastonite (manufactured by Kinsei Matec Co., Ltd.: SH600), aspect ratio 22, average particle size 18.6 μm

[0073] <Thickening agent> • Metal oxide nanoparticles: Silicon oxide nanoparticles (manufactured by Aerosil Japan: AEROSIL R976S), average primary particle size 7nm

[0074] <Polyisocyanate compounds> • MDI (manufactured by Sumika Covestro Urethane Co., Ltd., product name: 44V-20)

[0075] [Examples 1-8, Comparative Examples 1-2] The viscosity and caking of the polyol composition, as well as the flame retardancy of the polyurethane foam, were evaluated as follows.

[0076] <Viscosity> 300 mL of polyol composition prepared according to the formulations in Table 1 was placed in a 300 mL polypropylene cup, the liquid temperature of the polyol composition was adjusted to 25°C, and the viscosity was measured using a B-type viscometer. The viscosity measurement conditions were a spindle LV-03, rotation speed of 60 rpm, and a "BROOKFIELD DV2T" was used as the measuring device. The following criteria were used for evaluation. ○ Viscosity is 2000 mPa·s or less × Viscosity exceeding 2000 mPa·s

[0077] <Caking Evaluation> A polyol composition was prepared by mixing the components listed in Table 1. 400 mL of the polyol composition was placed in a cup (inner diameter × outer diameter × height (mm): 89 × 101 × 111) and stored in an oven at 23°C for 7 days. After storage, the caking was evaluated based on the following four criteria. (1) Visual evaluation 0 points: The solid flame retardant had separated (settled). 2 points: Separation (sedimentation) of solid flame retardant was not observed. (2) Drop evaluation I judged the state of the caking when I dropped the spatula. 0 points: Even with force applied, the liquid did not reach the bottom of the cup. 1 point: When force was applied, it reached the bottom of the cup. 2 points: It reached the bottom of the cup without any force being applied. (3) Redispersibility (re-stirring) evaluation 0 points: The time required to stir and redisperse the mixture was 3 minutes or more. 1 point: The time required for stirring and redispersion was less than 3 minutes. 2 points: It redispersed immediately with just a little stirring. (4) Assessment of re-settlement After being redistributed and left to stand for 18 hours, a visual evaluation was performed. 0 points: The solid flame retardant had separated (settled). 2 points: Separation (sedimentation) of solid flame retardant was not observed.

[0078] (Overall rating of the cake) Based on the total scores from the above-mentioned (1) visual evaluation, (2) drop evaluation, (3) redispersibility evaluation, and (4) resettling evaluation, a comprehensive evaluation of caking was conducted according to the following criteria. ○: Total score of 5 points or more. Cakeing was well controlled. △: Total score between 2 and 4 points. Cake was suppressed to a certain extent. ×: Total score is 1 point or less. Cakeing was not suppressed.

[0079] <Evaluation of flame retardancy (corn calorimeter test)> (Sample preparation) Polyol compositions prepared according to the formulations in Table 1, and liquid diphenylmethane diisocyanate (MDI) were introduced into a spray machine. Using a spray gun, a urethane resin composition consisting of a mixture of the polyol composition and MDI described in Table 1 was sprayed onto a substrate to form a polyurethane foam. The isocyanate indices of the urethane resin compositions are shown in Table 1. The details of the spraying machine and substrate are as follows. Spraying machine: Graco H-25 spraying device Settings (Heater settings) Isocyanate heater: 38℃ Premix heater (heater for polyol composition): 38℃ Hose heater: 38℃ Base material: Gypsum board Base material temperature: 20℃±1℃

[0080] (Measurement of total heat generation) As described above, polyurethane foam with gypsum board as a base was cut into pieces measuring 10 cm vertically, 10 cm horizontally, and 5 cm thick to prepare samples for cone calorimeter testing. The cone calorimeter test samples were tested for a radiant thermal intensity of 50 kW / m² in accordance with the ISO-5660 test method. 2 The total heat generated from 0 to 10 minutes of heating was calculated. <Evaluation Criteria> 〇 Total heat generation up to 10 minutes is 8 J / m³ 2 below × Total heat output up to 10 minutes is 8 J / m³ 2 super

[0081] [Table 1]

[0082] Note that the mass parts of each catalyst refer to the mass parts of the product.

[0083] The polyol compositions of each example, which contained a filler with an aspect ratio of 3 or more, exhibited suppressed caking and good flame retardancy of the polyurethane foam compared to the polyol composition of Comparative Example 1, which did not contain a filler with an aspect ratio of 3 or more. Comparative Example 2 was an example in which a larger amount of thickener was added without using a filler with an aspect ratio of 3 or more. Although caking was suppressed, the viscosity was too high to form a polyurethane foam, and therefore flame retardancy could not be evaluated.

Claims

1. A urethane resin composition comprising a polyol composition and a polyisocyanate for reacting with a polyisocyanate to obtain a polyurethane foam, wherein the polyol composition contains a polyol, a blowing agent, a catalyst, a solid flame retardant, a liquid flame retardant, a filler with an aspect ratio of 22 or more, and metal oxide fine particles, the solid flame retardant being a red phosphorus-based flame retardant, and having an isocyanate index of 250 or more.

2. The urethane resin composition according to claim 1, wherein the foaming agent contains a hydrofluoroolefin, and the amount of the hydrofluoroolefin is 10 to 40 parts by mass per 100 parts by mass of the polyol.

3. The urethane resin composition according to claim 1 or 2, wherein the catalyst comprises a trimerizing catalyst.

4. The urethane resin composition according to claim 3, wherein the trimerizing catalyst contains a quaternary ammonium salt.

5. The urethane resin composition according to claim 1 or 2, wherein the catalyst comprises an imidazole derivative.

6. The urethane resin composition according to claim 1 or 2, wherein the catalyst comprises at least one metal catalyst selected from the group consisting of bismuth and tin.

7. A urethane resin composition according to claim 1 or 2, for use in spraying.

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