Laminate

Abstract

To provide a laminate that includes a polyurethane foam, and a coating layer laminated on the surface of the polyurethane foam, exhibiting improved flame retardancy.SOLUTION: A laminate includes a polyurethane foam, and a coating layer laminated on the surface of the polyurethane foam. The polyurethane foam contains a solid phosphorous flame retardant. The coating layer contains limestone and metal hydroxide.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a laminate comprising a polyurethane foam and a skin layer. [Background technology]

[0002] Taking advantage of their excellent heat insulating properties, polyurethane foams are put to practical use for heat insulation and condensation prevention in various structures such as ceilings, roofs, and walls of buildings such as apartment complexes, detached houses, commercial buildings, etc. Polyurethane foams are formed, for example, by spraying a urethane resin composition containing a polyol composition and a polyisocyanate onto the surface of each structure, followed by foaming and curing.

[0003] Generally used polyurethane foams have excellent heat insulating properties, but tend to be vulnerable to heat, and there is a demand for polyurethane foams with excellent heat resistance. Patent Document 1 discloses an invention relating to a composite heat insulating layer forming method, which is characterized by forming an inorganic foam composition layer made of a foamed mortar hardened body obtained by adding aluminum powder to a slurry material mainly composed of a calcareous raw material such as cement on the surface of a synthetic resin foam such as a polyurethane foam. It also describes that such a method improves heat resistance. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Unexamined Patent Publication No. 61-72544 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, it is generally known to form a coating layer of a cement material or the like on the surface of a polyurethane foam, which has a certain degree of flame retardancy, such as preventing the surface from burning. However, from the viewpoint of preventing ignition of polyurethane foam, higher flame retardancy is required. Specifically, the challenge is to reduce the maximum heat release rate and total heat release amount, as evaluated by the cone calorimeter test, from the conventional level. Therefore, an object of the present invention is to provide a laminate comprising a polyurethane foam and a coating layer, which has a lower maximum heat generation rate and total heat generation amount and has improved flame retardancy than conventional laminates. [Means for solving the problem]

[0006] As a result of intensive research, the present inventors have found that the above-mentioned problems can be solved by a laminate comprising a polyurethane foam and a coating layer laminated on a surface of the polyurethane foam, the polyurethane foam containing a solid phosphorus-based flame retardant, and the coating layer containing limestone and a metal hydroxide, and have completed the present invention. That is, the present invention provides the following items [1] to

[10] .

[0007] [1] A laminate comprising a polyurethane foam and a coating layer laminated on a surface of the polyurethane foam, the polyurethane foam containing a solid phosphorus-based flame retardant, and the coating layer containing limestone and a metal hydroxide. [2] The laminate according to the above [1], wherein the coating layer is formed from a coating material containing limestone, metal hydroxide, and water. [3] The laminate according to the above [1] or [2], wherein the metal hydroxide is at least one selected from the group consisting of magnesium hydroxide and aluminum hydroxide. [4] The laminate according to the above [2] or [3], wherein the content of the metal hydroxide in the coating material is 3 to 80 mass % based on the total solid content. [5] The laminate according to any one of the above [1] to [4], wherein the polyurethane foam is formed from a urethane resin composition containing a polyol, a polyisocyanate, a catalyst, a foaming agent, and a solid phosphorus-based flame retardant. [6] The laminate according to [5] above, wherein the catalyst comprises a trimerization catalyst. [7] The laminate according to [6] above, wherein the trimerization catalyst contains a quaternary ammonium salt. [8] The laminate according to any one of the above [5] to [7], wherein the catalyst comprises at least one metal catalyst selected from the group consisting of bismuth and tin. [9] The laminate according to any one of the above [5] to [8], wherein the catalyst comprises an imidazole derivative.

[10] The laminate according to any one of the above [5] to [9], wherein the urethane resin composition is for spray application. Effect of the Invention

[0008] According to the present invention, it is possible to provide a laminate comprising a polyurethane foam and a coating layer, which has a lower maximum heat generation rate and total heat generation amount than conventional laminates, and has improved flame retardancy. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The present invention is a laminate comprising a polyurethane foam and a coating layer laminated on a surface of the polyurethane foam, wherein the polyurethane foam contains a solid phosphorus-based flame retardant, and the coating layer contains limestone and a metal hydroxide.

[0010] The laminate of the present invention has a coating layer laminated on the surface of a polyurethane foam. The coating layer is preferably laminated on one surface of the polyurethane foam. Generally, polyurethane foam is weak against heat, but the laminate of the present invention has a polyurethane foam containing a solid phosphorus-based flame retardant and a coating layer containing a metal hydroxide, so that the maximum heat generation rate and the total heat generation amount are low, and ignition can be easily prevented.

[0011] [Polyurethane foam] The polyurethane foam in the present invention is formed from a urethane resin composition containing a polyol, a polyisocyanate, a catalyst, a blowing agent, and a solid phosphorus-based flame retardant. The urethane resin composition is preferably for spraying. That is, the urethane resin composition is used by spraying onto any structure, and a polyurethane foam is formed on the structure. The spraying can be carried out using a spraying device or the like, as described in detail below.

[0012] <Polyol> The urethane resin composition of the present invention contains a polyol. Examples of the polyol include polylactone polyol, polycarbonate polyol, polyester polyol, polymer polyol, and polyether polyol.

[0013] Examples of the polylactone polyol include polypropiolactone glycol, polycaprolactone glycol, and polyvalerolactone glycol. Examples of polycarbonate polyols include polyols obtained by dealcoholization reaction of hydroxyl group-containing compounds such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, octanediol, and nonanediol with ethylene carbonate, propylene carbonate, and the like.

[0014] Examples of polyester polyols include polymers obtained by dehydration condensation of polybasic acids and polyhydric alcohols, and condensates of hydroxycarboxylic acids and the above-mentioned 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.

[0015] Examples of the polymer polyol include polymers obtained by graft polymerizing an ethylenically unsaturated compound such as acrylonitrile, styrene, methyl acrylate, or methacrylate with an aromatic polyol, an alicyclic polyol, an aliphatic polyol, or a polyester polyol, or polybutadiene polyol, or hydrogenated products thereof.

[0016] Examples of polyether polyols include polymers obtained by ring-opening polymerization of alkylene oxides having 2 to 6 carbon atoms, specifically at least one of ethylene oxide, propylene oxide, tetrahydrofuran, etc., in the presence of at least one low-molecular-weight active hydrogen compound having two or more active hydrogens, such as polyhydric alcohols. 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 hydrogens include diols such as bisphenol A, ethylene glycol, propylene glycol, butylene glycol, and 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 derivatives thereof; phloroglucinol, cresol, etc. polyols such as pyrogallol, catechol, hydroquinone, bisphenol A, bisphenol F, bisphenol S, 1,3,6,8-tetrahydroxynaphthalene, and 1,4,5,8-tetrahydroxyanthracene; polyfunctional (for example, having 2 to 100 functional groups) polyols such as castor oil polyol, (co)polymers of hydroxyalkyl (meth)acrylate, and polyvinyl alcohol; condensates of phenol and formaldehyde (novolaks); and amines such as ethylenediamine and butylenediamine. As the polyether polyol, a Mannich polyether polyol may be used. The Mannich polyether polyol is obtained by utilizing the Mannich reaction and is a Mannich condensation product having two or more hydroxyl groups in the molecule, or a polyether polyol obtained by adding an alkylene oxide to such a Mannich condensation product.

[0017] The polyol used in the present invention is preferably a polyester polyol or a polyether polyol. Also, a polyol having two hydroxyl groups is preferable. Among them, from the viewpoint of improving the flame retardancy of the polyurethane foam, an aromatic polyester polyol, which is a polyester polyol having an aromatic ring, is preferable. The aromatic polyester polyol is preferably a condensation product 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. Among these, from the viewpoint of enhancing the flame retardancy of the polyurethane foam, particularly the flame spread prevention performance, the aromatic polyester polyol more preferably contains a phthalic acid-based polyester polyol which is a condensation product of phthalic acid and a glycol, and further preferably contains at least one selected from p-phthalic acid-based polyester polyol which is a condensation product of p-phthalic acid and a glycol, and o-phthalic acid-based polyester polyol which is a condensation product of o-phthalic acid and a glycol.

[0018] When the polyol contains an aromatic polyester polyol, the content 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.

[0019] The weighted average hydroxyl value of the polyol is preferably 20 to 350 mgKOH / g, more preferably 50 to 300 mgKOH / g, and even more preferably 100 to 280 mgKOH / g. When the hydroxyl value of the polyol is equal to or less than the upper limit, the viscosity of the polyol composition is likely to decrease, which is preferable from the viewpoint of handleability, etc. On the other hand, when the hydroxyl value of the polyol is equal to or more than the lower limit, the crosslink density of the polyurethane foam increases, thereby increasing the strength and improving the workability when sprayed. The hydroxyl value of the polyol can be measured in accordance with JIS K 1557-1:2007.

[0020] Here, the weighted average hydroxyl value of the polyol is calculated by the sum of the products of the hydroxyl values ​​of the individual polyols constituting the polyol and the weight fractions of the individual polyols in the polyol. For example, when two types of polyols (d1) and (d2) are used as the polyol, the hydroxyl value of the polyol (d1) is X1, the blending amount is m1, the hydroxyl value of the polyol (d2) is X2, and the blending amount is m2, the weighted average hydroxyl value is expressed by the following formula. The blending amounts m1 and m2 are parts by mass in 100 parts by mass of the polyol. Weighted average hydroxyl value (mgKOH / g)=X1×(m1 / (m1+m2))+X2×(m2 / (m1+m2))

[0021] <Solid phosphorus-based flame retardant> The urethane resin composition in the present invention contains a solid phosphorus-based flame retardant. A laminate including a polyurethane foam formed from a urethane resin composition containing a solid phosphorus-based flame retardant is preferable because it has a low maximum heat release rate and a low total heat release amount. Here, "solid" means that the material is in a solid state at room temperature (25° C.) and normal pressure (1 atm).

[0022] Examples of solid phosphorus-based flame retardants include red phosphorus-based flame retardants, phosphate-containing flame retardants, and phosphinic acid-based flame retardants. Among them, the solid phosphorus-based flame retardant preferably includes a red phosphorus-based flame retardant. The solid phosphorus-based flame retardants may be used alone or in combination of two or more.

[0023] (Red phosphorus flame retardant) The red phosphorus-based flame retardant may be red phosphorus alone, red phosphorus coated with a resin, a metal hydroxide, a metal oxide, or the like, or red phosphorus mixed with a resin, a metal hydroxide, a metal oxide, or the like. The resin that coats the red phosphorus or is mixed with the red phosphorus is not particularly limited, but examples thereof include thermosetting resins such as phenol 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 hydroxide may be appropriately selected from those described in the metal hydroxide-based flame retardant described later.

[0024] (Phosphate-containing flame retardants) Examples of the phosphate-containing flame retardant include phosphates consisting of a salt of phosphoric acid and at least one metal or compound selected from metals of Groups IA to IVB of the periodic table, ammonia, aliphatic amines, and aromatic amines. The phosphoric acid is not particularly limited, and examples thereof include various phosphoric acids such as monophosphoric acid, pyrophosphoric acid, and polyphosphoric acid. Examples of the metals in Groups IA to IVB of the periodic table include lithium, sodium, calcium, barium, iron (II), iron (III), aluminum, etc. Examples of the aliphatic amines include methylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, piperazine, etc. Examples of the aromatic amines include pyridine, triazine, melamine, etc. The above-mentioned phosphate-containing flame retardants may be subjected to a known water resistance improving treatment, such as treatment with a silane coupling agent or coating with a melamine resin.

[0025] Specific examples of phosphate-containing flame retardants include monophosphates, pyrophosphates, polyphosphates, and the like. Examples of monophosphates include, but are not limited to, 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 monohydrogen magnesium 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.

[0026] The polyphosphate is not particularly limited, but examples thereof include ammonium polyphosphate, piperazine polyphosphate, melamine polyphosphate, ammonium amide polyphosphate, aluminum polyphosphate, etc. Among these, it is more preferable to use the polyphosphate. The phosphate-containing flame retardants may be used alone or in combination of two or more.

[0027] (Phosphinic acid flame retardants) Examples of phosphinic acid 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] The content of the solid phosphorus-based flame retardant in the urethane resin composition is preferably 5 to 150 parts by mass, more preferably 10 to 120 parts by mass, and even more preferably 15 to 100 parts by mass, based on 100 parts by mass of the polyol. When the content of the solid phosphorus-based flame retardant is equal to or more than the lower limit, the polyurethane foam can be provided with good flame retardancy, and the total heat generation amount and maximum heat generation rate of the laminate can be reduced. When the content of the solid phosphorus-based flame retardant is equal to or less than the upper limit, the urethane resin composition can be dispersed over a wide area by spraying, and the formed polyurethane foam has good adhesion to the target to which it is sprayed.

[0029] <Solid flame retardants other than solid phosphorus-based flame retardants> The urethane resin composition of the present invention may contain a solid flame retardant other than the above-mentioned solid phosphorus-based flame retardant. Examples of the solid flame retardant other than the solid phosphorus-based flame retardant include a boron-based flame retardant, a bromine-containing flame retardant, an antimony-containing flame retardant, and a metal hydroxide-based flame retardant. In addition, the term "solid flame retardant" may be used to refer to both "solid phosphorus-based flame retardants" and "solid flame retardants other than solid phosphorus-based flame retardants."

[0030] (Boron-based flame retardants) Specific examples of the boron-based flame retardant include alkali metal borate such as lithium borate, sodium borate, potassium borate, and cesium borate, alkaline earth metal borate such as magnesium borate, calcium borate, and barium borate, zirconium borate, zinc borate, aluminum borate, and ammonium borate, etc. Among these, zinc borate is preferred.

[0031] (Brominated flame retardants) The brominated flame retardant is not particularly limited as long as it is a compound containing bromine in its molecular structure, and examples thereof include aromatic brominated compounds. Specific examples of the aromatic brominated compound include monomeric organic bromine compounds such as hexabromobenzene, pentabromotoluene, hexabromobiphenyl, decabromobiphenyl, hexabromocyclodecane, decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, bis(pentabromophenoxy)ethane, ethylene bis(pentabromophenyl), ethylene bis(tetrabromophthalimide), and tetrabromobisphenol A; polycarbonate oligomers produced using brominated bisphenol A as a raw material; and a mixture of the polycarbonate oligomer and bisphenol A. and copolymers thereof; brominated epoxy compounds such as diepoxy compounds produced by the reaction of brominated bisphenol A with epichlorohydrin and monoepoxy compounds obtained by the reaction of brominated phenols with epichlorohydrin; halogenated bromine compound polymers such as poly(brominated benzyl acrylate), brominated polyphenylene ether, brominated bisphenol A, condensates of cyanuric chloride and brominated phenol, brominated (polystyrene), poly(brominated styrene), brominated polystyrenes such as crosslinked brominated polystyrene, and crosslinked or non-crosslinked brominated poly(α-methylstyrene). Among these, ethylene bis(pentabromophenyl), ethylene bis(tetrabromophthalimide), hexabromobenzene, and the like are preferable.

[0032] (Antimony-containing flame retardants) Examples of the antimony-containing flame retardant used in the present invention include antimony oxide, antimonates, and pyroantimonates. 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. Preferably, the antimony-containing flame retardant is antimony oxide. The antimony-containing flame retardants may be used alone or in combination of two or more.

[0033] (Metal hydroxide flame retardant) Examples of metal hydroxide flame retardants include magnesium hydroxide, calcium hydroxide, aluminum hydroxide, iron hydroxide, nickel hydroxide, zirconium hydroxide, titanium hydroxide, zinc hydroxide, copper hydroxide, vanadium hydroxide, tin hydroxide, etc. The metal hydroxide flame retardants may be used alone or in combination of two or more.

[0034] The content of solid flame retardants other than solid phosphorus-based flame retardants is, for example, 70 mass % or less, preferably 60 mass % or less, and more preferably 50 mass % or less, based on the total amount of solid flame retardants.

[0035] (Fillers other than solid flame retardants) The urethane resin composition may contain a filler other than the solid flame retardant. The filler other than the solid flame retardant is solid at room temperature (25°C) and normal pressure (1 atm), and exists as a powder in the urethane resin composition. As the filler other than the solid flame retardant, alumina, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, ferrites, basic magnesium carbonate, calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, dawsonite, hydrotalcite, calcium sulfate, barium sulfate, calcium silicate, talc, clay, mica, montmorillonite, bentonite, activated clay, imogolite, sericite, glass beads, silica balloon, aluminum nitride, boron nitride, silicon nitride, graphite, carbon balloon, charcoal powder, various metal powders, magnesium sulfate, lead zirconate titanate, molybdenum sulfide, silicon carbide, various magnetic powders, fly ash, etc. can be appropriately used. The fillers other than the solid flame retardant may be used alone or in combination of two or more kinds.

[0036] (Liquid flame retardant) The urethane resin composition of the present invention preferably contains a liquid flame retardant. The liquid flame retardant is one that is liquid at room temperature (25°C) and normal pressure (1 atm). The liquid flame retardant is not particularly limited, but a phosphate flame retardant is preferred.

[0037] As the phosphate flame retardant, monophosphate ester, condensed phosphate ester, etc. can be used. Monophosphate ester is a phosphate ester having one phosphorus atom in the molecule. Examples of monophosphate ester 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, cresyl diphenyl phosphate, and diphenyl(2-ethylhexyl)phosphate, and acidic phosphate esters such as monoisodecyl phosphate and diisodecyl phosphate.

[0038] Examples of the condensed phosphate ester include aromatic condensed phosphate esters such as trialkyl polyphosphate, resorcinol polyphenyl phosphate, bisphenol A polycresyl phosphate, and bisphenol A polyphenyl phosphate. Commercially available condensed phosphate esters include, for example, "CR-733S", "CR-741", and "CR747" manufactured by Daihachi Chemical Industry Co., Ltd., and "ADEKA STAB PFR" and "FP-600" manufactured by ADEKA Corporation.

[0039] The phosphoric acid ester-based flame retardant may be used alone or in combination of two or more of the above-mentioned. Among them, from the viewpoint of easily adjusting the viscosity of the urethane resin composition to an appropriate value and from the viewpoint of improving the flame retardancy of the polyurethane foam, monophosphate ester is preferred, and halogen-containing phosphoric acid ester such as tris(β-chloropropyl)phosphate is more preferred.

[0040] The content of the liquid flame retardant in the urethane resin composition is not particularly limited, but is preferably 15 to 100 parts by mass, more preferably 20 to 80 parts by mass, and even more preferably 25 to 70 parts by mass, relative to 100 parts by mass of the polyol. When the content of the liquid flame retardant is equal to or greater than these lower limits, flame retardancy can be easily imparted to the polyurethane foam without excessively increasing the viscosity of the urethane resin composition or the content of powder such as a solid flame retardant, etc. When the content of the liquid flame retardant is equal to or less than these upper limits, foaming is not inhibited, and the polyurethane foam can be easily produced.

[0041] <Catalyst> The urethane resin composition of the present invention contains a catalyst. The catalyst may contain, for example, one or both of a urethanization catalyst and a trimerization catalyst, and preferably contains both.

[0042] (trimerization catalyst) The trimerization catalyst is a catalyst that reacts the isocyanate groups contained in the polyisocyanate to trimerize them and promote the formation of isocyanurate rings. By including the trimerization catalyst, a polyurethane foam containing a polyisocyanurate structure is formed, and fire resistance can be improved. In addition, the reaction of the isocyanate groups is completed, making it easier to obtain a polyurethane foam with good foaming properties.

[0043] Examples of the trimerization catalyst include metal catalysts, ammonium salts, etc. Examples of the metal catalyst (trimerization metal catalyst) used as the trimerization catalyst include potassium organic acids, and preferred are potassium octylates 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, quaternary ammonium salts such as tetramethylammonium salt, tetraethylammonium salt and tetraphenylammonium salt, etc. can be used, among which quaternary ammonium salts are preferred. The ammonium salt is, for example, an ammonium salt of a carboxylic acid. As the carboxylic acid in the ammonium salt, for example, a saturated fatty acid having 1 to 10 carbon atoms, preferably 2 to 8 carbon atoms, can be mentioned. The saturated fatty acid may have a hydrocarbon group that is linear or branched, but preferably has a branched group. Specific examples of the carboxylic acid include 2-ethylhexanoic acid, 2,2-dimethylpropanoic acid, acetic acid, and formic acid, and among these, 2,2-dimethylpropanoic acid is preferred. The trimerization catalyst may be used alone or in combination of two or more kinds. From the viewpoint of improving the adhesion between the polyurethane foam and the coating layer, the trimerization catalyst preferably contains a quaternary ammonium salt and a metal catalyst (trimerization metal catalyst).

[0044] The content of the quaternary ammonium salt in the urethane resin composition is preferably 0.5 to 15 parts by mass, more preferably 1 to 12 parts by mass, and even more preferably 3 to 10 parts by mass, based on 100 parts by mass of the polyol. By making the content of the quaternary ammonium salt equal to or greater than the lower limit, the adhesion between the polyurethane foam and the coating layer formed can be improved. In addition, by making the content of the trimerization catalyst equal to or less than the upper limit, the reaction rate can be appropriately controlled. The content of the metal catalyst (trimerization metal catalyst) in the urethane resin composition is not particularly limited, but is preferably 0.2 to 10 parts by mass, more preferably 0.3 to 8 parts by mass, and even more preferably 0.6 to 5 parts by mass, per 100 parts by mass of the polyol. The content of the trimerization catalyst in the urethane resin composition is preferably from 0.7 to 25 parts by mass, more preferably from 1.5 to 20 parts by mass, and even more preferably from 4 to 15 parts by mass, relative to 100 parts by mass of the polyol.

[0045] (Urethanization catalyst) The catalyst in the present invention preferably contains a urethanization catalyst. The urethanization catalyst preferably contains a nitrogen-containing heterocyclic compound. By containing a nitrogen-containing heterocyclic compound as the urethanization catalyst, the stability against the hydrofluoroolefin described below is improved, thereby preventing the decomposition of the hydrofluoroolefin and improving the foaming property. In addition, the reaction rate can be made to be at least a certain level, and the workability when spraying the urethane resin composition can be improved. Among the nitrogen-containing heterocyclic compounds, the catalyst in the present invention more preferably contains an imidazole derivative. As described above, the imidazole derivative is less susceptible to the influence of the hydrofluoroolefin, and makes it easier to react the polyol with the polyisocyanate while increasing the stability of the polyol composition. Therefore, by containing the imidazole derivative, the urethane resin composition has increased reactivity between the polyol and the polyisocyanate, and further improved foamability. The imidazole derivative is preferably an imidazole substituted at the 1- and 2-positions with an alkyl group having 8 or less carbon atoms, and the alkyl group preferably has 6 or less carbon atoms, more preferably has 4 or less carbon atoms. A specific example of a suitable imidazole derivative is represented by the following general formula (1).

[0046] [ka] (In general formula (1), R 1 and R 2 each independently represents an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms.

[0047] R in general formula (1) 1 and R 2 each independently represents 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 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, and an octyl group. 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, and an octenyl group. R 1 and R 2 When the number of carbon atoms in the alkyl group or alkenyl group in R is equal to or greater than the lower limit, steric hindrance increases and the copolymer is less susceptible to the effects of blowing agents such as hydrofluoroolefins, which is preferable. 1 and R 2 When the number of carbon atoms in the alkyl group is equal to or less than the upper limit, the steric hindrance is not extremely large, so that the reaction between the polyol and the polyisocyanate can proceed quickly, and the foaming properties are also good. From these perspectives, R 1 and R 2 are each independently preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms, and further preferably a methyl group.

[0048] The imidazole derivative represented by general formula (1) includes 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 the activity of the catalyst in the presence of hydrofluoroolefin and from the viewpoint of rapidly progressing the reaction. In addition, 1,2-dimethylimidazole is more preferred from the viewpoint of further increasing stability.

[0049] The content of the nitrogen-containing heterocyclic compound in the urethane resin composition is preferably 0.1 to 20 parts by mass, more preferably 1 to 15 parts by mass, and even more preferably 2 to 10 parts by mass, based on 100 parts by mass of the polyol. When the content of the nitrogen-containing heterocyclic compound is equal to or more than the lower limit, the formation of urethane bonds is easily generated, the reaction proceeds quickly, and the foaming property is good. On the other hand, when the content of the nitrogen-containing heterocyclic compound is equal to or less than the upper limit, the reaction rate is easily controlled, which is preferable.

[0050] The urethanization catalyst preferably contains a metal catalyst in addition to the nitrogen-containing heterocyclic compound. This metal catalyst is generally called a urethanization metal catalyst. In the present invention, the inclusion of the urethanization metal catalyst promotes the reaction between the polyol and the polyisocyanate, and in particular increases the initial reaction rate. In addition, the inclusion of the urethanization metal catalyst makes it easier to maintain good foamability of the urethane resin composition. From the viewpoint of foamability, the catalyst preferably contains at least one metal catalyst (urethanization metal catalyst) selected from the group consisting of bismuth and tin, and more preferably contains bismuth. Bismuth has low reactivity with hydrofluoroolefins described later and increases storage stability. In addition, it is easy to improve the initial activity without decreasing the flame retardancy of the polyurethane foam.

[0051] The urethane metal catalyst is preferably a metal salt selected from bismuth and tin, more preferably a bismuth salt. The metal salt is preferably an organic acid metal salt, more preferably a metal salt of a carboxylic acid having 5 or more carbon atoms. The carboxylic acid has 5 or more carbon atoms, and thus has good stability against a blowing agent, particularly hydrofluoroolefin. In addition, the number of carbon atoms of the carboxylic acid is preferably 18 or less, more preferably 12 or less, from the viewpoint of catalytic activity. The carboxylic acid is preferably an aliphatic carboxylic acid, more preferably a saturated aliphatic carboxylic acid. The carboxylic acid may be linear or may have a branched structure, but preferably has a branched structure. Specific examples of carboxylic acids include octyl acid, lauric acid, versatic acid, pentanoic acid, and acetic acid, and among these, octyl acid is preferred. That is, the transition metal salt is preferably a metal salt of octyl acid. These carboxylic acids may be linear as described above, but may also have a branched structure. An example of an octyl acid having a branched structure is 2-ethylhexanoic acid. As the metal salt of carboxylic acid, bismuth salt of carboxylic acid and tin salt of carboxylic acid are preferable, and among them, bismuth salt of octylic acid is preferable. In addition, the metal salt of carboxylic acid may be a carboxylate of an alkyl metal. For example, the tin salt of carboxylic acid may be a dialkyltin carboxylate, and preferably is a dioctyltin carboxylate. Specific examples of metal salts of carboxylic acids include bismuth trioctate, dioctyltin versatate, dibutyltin dilaurate, dioctyltin dilaurate, tin dioctylate, etc., and are preferably bismuth trioctate or dioctyltin versatate, and more preferably bismuth trioctate.

[0052] The content of the urethanization metal catalyst in the urethane resin composition is not particularly limited, but is preferably 0.05 to 8 parts by mass, more preferably 0.1 to 5 parts by mass, and even more preferably 0.3 to 3 parts by mass, relative to 100 parts by mass of the polyol.

[0053] <Foaming agent> The urethane resin composition of the present invention contains a foaming agent. Specific examples of the foaming agent include water, low-boiling point hydrocarbons, chlorinated aliphatic hydrocarbon compounds, fluorine compounds, hydrochlorofluorocarbon compounds, hydrofluorocarbons, ether compounds, and hydrofluoroolefins. In addition, examples of the foaming agent include organic physical foaming agents such as mixtures of these compounds, and inorganic physical foaming agents such as nitrogen gas, oxygen gas, argon gas, and carbon dioxide gas. Examples of the low boiling point hydrocarbon include propane, butane, pentane, hexane, heptane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, and cycloheptane. Examples of the chlorinated aliphatic hydrocarbon compounds include dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, and isopentyl chloride. Examples of the fluorine compound include CHF3, CH2F2, and CH3F. Examples of the hydrochlorofluorocarbon compounds include trichloromonofluoromethane, trichlorotrifluoroethane, and dichloromonofluoroethane (for example, HCFC141b (1,1-dichloro-1-fluoroethane), HCFC22 (chlorodifluoromethane), and HCFC142b (1-chloro-1,1-difluoroethane)). Examples of the hydrofluorocarbon include HFC-245fa (1,1,1,3,3-pentafluoropropane) and HFC-365mfc (1,1,1,3,3-pentafluorobutane). The ether compound may, for example, be diisopropyl ether. Examples of the hydrofluoroolefin 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,-hexafluorobut-2-ene), and HFO-1224yd(Z).

[0054] Among the above, the foaming agent is preferably a hydrofluoroolefin, water, etc., and more preferably a combination of a hydrofluoroolefin and water. As the water used as the foaming agent, for example, ion-exchanged water, distilled water, etc. can be appropriately used.

[0055] The content of the foaming agent is preferably 10 to 70 parts by mass, more preferably 15 to 65 parts by mass, and even more preferably 20 to 60 parts by mass, per 100 parts by mass of polyol, from the viewpoint of adjusting the density and improving the adhesion between the polyurethane foam and the coating layer.

[0056] When a hydrofluoroolefin is used as the foaming agent, the content of the hydrofluoroolefin is preferably 5 to 65 parts by mass, more preferably 10 to 60 parts by mass, and even more preferably 15 to 55 parts by mass, per 100 parts by mass of polyol, from the viewpoints of adjusting the density and improving the adhesion between the polyurethane foam and the coating layer. When water is used as the foaming agent, the content of water 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, from the viewpoint of improving adhesion between the polyurethane foam and the coating layer.

[0057] <Foam stabilizer> The urethane resin composition of the present invention may contain a foam stabilizer. As the foam stabilizer, a compound having a polar portion and a non-polar portion in the molecule and having a surface active effect can be suitably used. The foam stabilizer is not particularly limited, but examples thereof include surfactants such as polyoxyalkylene foam stabilizers such as polyoxyalkylene alkyl ethers, silicone foam stabilizers such as organopolysiloxanes, etc. In addition, the silicone foam stabilizer may be a graft copolymer of polyoxyalkylene glycol, which is a polymer of ethylene oxide or propylene oxide, and polydimethylsiloxane. In addition, commercially available products can be used, and specifically, foam stabilizers such as SH-193 (manufactured by Dow Corning Toray Co., Ltd.), B8467 (manufactured by Evonik Co., Ltd.), F501 (Shin-Etsu Chemical Co., Ltd.), and SF-2937F (manufactured by Dow Toray Co., Ltd.) can be used. The content of the foam stabilizer 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 the polyol. When the content of the foam stabilizer is equal to or less than these upper limits, the surface condition of the polyurethane foam becomes good, and the adhesion between the polyurethane foam and the coating layer is easily improved. The content of the foam stabilizer 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, relative to 100 parts by mass of the polyol. When the content of the foam stabilizer is equal to or more than these lower limits, the foaming stability is easily improved.

[0058] <Polyisocyanate> The urethane resin composition of the present invention contains a polyisocyanate. As the polyisocyanate contained in the urethane resin composition, various polyisocyanate compounds having two or more isocyanate groups, such as aromatic, alicyclic, and aliphatic polyisocyanate compounds, can be used. It is preferable to use liquid diphenylmethane diisocyanate (MDI) because of 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 examples of commercially available liquid MDI include "44V-10" and "44V-20" (manufactured by Sumika Covestro Urethane Co., Ltd.), and "Millionate MR-200" (Nippon Polyurethane Industry Co., Ltd.). In addition, uretonimine-containing MDI (for example, a commercially available product "Millionate MTL": manufactured by Nippon Polyurethane Industry Co., Ltd.) may also be used. In addition, a polyisocyanate compound in which a part of the isocyanate active group has been reacted with a hydroxyl group-containing compound and treated in advance to enhance affinity with polyol may also be used. In addition to liquid MDI, other polyisocyanates may be used in combination, and as the polyisocyanate to be used in combination, any polyisocyanate known in the technical field of polyurethanes can be used without any limitations.

[0059] The isocyanate index of the urethane resin composition of the present invention is preferably 150 or more, more preferably 200 or more, and even more preferably 250 or more, from the viewpoints of properly forming a polyurethane foam and imparting good flame retardancy. The isocyanate index of the urethane resin composition is preferably not more than 800, more preferably not more than 600, and even more preferably not more than 500. When the isocyanate index is not more than these upper limit values, flame retardancy that is sufficiently commensurate with the production costs can be obtained. The isocyanate index (INDEX) is calculated as follows.

[0060] INDEX = equivalents of polyisocyanate ÷ (equivalents of polyol + equivalents of water) × 100 Where: Polyisocyanate equivalent number = number of parts of polyisocyanate used x NCO content (%) x 100 / NCO molecular weight Polyol equivalent number = OHV × number of parts of polyol used ÷ molecular weight of KOH, OHV is the hydroxyl value of polyol (mgKOH / g), Equivalents of water = parts of water used × number of OH groups in water / molecular weight of water In the above formula, the unit of the 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 as mass%, and for convenience of unit conversion in the above formula, the molecular weight of KOH is 56100, the molecular weight of water is 18, and the number of OH groups in water is 2.

[0061] The content of the polyisocyanate in the urethane resin composition may be appropriately adjusted so as to fall within the above-mentioned isocyanate index range, and is, for example, 100 to 600 parts by mass, and preferably 150 to 450 parts by mass, relative to 100 parts by mass of the polyol.

[0062] (Other ingredients) The urethane resin composition in the present invention may contain one or more selected from phenol-based, amine-based, sulfur-based and other antioxidants, heat stabilizers, light stabilizers, metal damage inhibitors, antistatic agents, stabilizers, crosslinking agents, lubricants, softeners, pigments, dyes, and the like, as necessary, within the scope of the object of the present invention.

[0063] The method for producing the urethane resin composition of the present invention is not particularly limited, and can be produced, for example, by mixing each component. The urethane resin composition can be produced by mixing each component as described above, but it is preferable to prepare a polyol composition containing the above-mentioned polyol, catalyst, foaming agent, and solid phosphorus-based flame retardant first, and then mix the polyol composition with polyisocyanate to prepare the urethane resin composition. The polyol composition may contain a solid flame retardant, liquid flame retardant, etc. other than the above-mentioned solid phosphorus-based flame retardant.

[0064] The polyurethane foam in the present invention is formed from the above-mentioned urethane resin composition, specifically, is obtained by foaming and curing the urethane resin composition.

[0065] (Foam density, thickness) The density of the polyurethane foam in the present invention is not particularly limited, but is preferably 30 kg / m 3 It is preferable that the density is 30 kg / m or more. 3 By setting the density to 33 kg / m or more, shrinkage of the polyurethane foam is reduced, and peeling of the coating layer from the polyurethane foam constituting the laminate is easily suppressed. From this viewpoint, the density of the polyurethane foam is preferably 33 kg / m or less. 3 More preferably, it is 35 kg / m 3 That's all. In addition, from the viewpoints of reducing the weight of polyurethane foam and workability to the target object, the density of polyurethane foam is set at 200 kg / m 3 It is preferable that the saturation temperature is 100 kg / m or less. 3 It is more preferable that the density of the polyurethane foam is not more than 100%.

[0066] The thickness of the polyurethane foam in the present invention is not particularly limited, but is, for example, 10 to 200 mm, and preferably 15 to 100 mm.

[0067] [Coating layer] The laminate of the present invention includes a coating layer laminated on the surface of the polyurethane foam. The coating layer contains limestone and metal hydroxide and can suppress ignition of the polyurethane foam at high temperatures, etc. The coating layer is formed of a coating material containing limestone, metal hydroxide, and water. The coating material for forming the coating layer will be described below.

[0068] (limestone) The coating material in the present invention contains limestone. The limestone is preferably limestone contained as one component of a cement material. Therefore, the coating material preferably contains a cement material containing limestone. This improves the mechanical strength and flame retardancy of the coating layer. Examples of the cement material include portland cement, white cement, blast furnace cement, silica cement, and fly ash cement, and among these, white cement is preferred. The amount of limestone contained in the coating material is not particularly limited, but is, for example, 10 to 100 mass %, preferably 20 to 85 mass %, and more preferably 40 to 80 mass % based on the total solid content. The amount of limestone contained in the coating material based on the total solid content is equivalent to the amount of limestone contained in the coating layer formed by the coating material.

[0069] (metal hydroxide) The coating material in the present invention contains a metal hydroxide. By containing a metal hydroxide, the flame retardancy of the coating layer formed by the coating material is improved. This is believed to be because the metal hydroxide dehydrates and absorbs heat at high temperatures, inhibiting the progress of heat. As a result, the total heat generation amount and maximum heat generation rate of the laminate of the coating layer and polyurethane foam can be reduced. The type of metal hydroxide is not particularly limited, and examples thereof include magnesium hydroxide, aluminum hydroxide, calcium hydroxide, iron hydroxide, nickel hydroxide, zirconium hydroxide, titanium hydroxide, zinc hydroxide, copper hydroxide, vanadium hydroxide, tin hydroxide, etc. Among these, from the viewpoint of improving flame retardancy, the metal hydroxide is preferably at least one selected from the group consisting of magnesium hydroxide and aluminum hydroxide, and more preferably aluminum hydroxide.

[0070] The content of the metal hydroxide in the coating material is not particularly limited, but is, for example, 3 to 80 mass %, preferably 5 to 60 mass %, and more preferably 10 to 45 mass %, based on the total solid content. The content of the metal hydroxide in the coating material based on the total solid content is equivalent to the content of the metal hydroxide in the coating layer formed by the coating material.

[0071] (water) The coating material contains water as an additional component in addition to the limestone and metal hydroxide described above. The inclusion of water increases the fluidity of the coating material, making it easier to form a coating layer on a polyurethane foam by coating or the like. The water content in the coating material is not particularly limited, but is, for example, 50 to 500 parts by mass, preferably 80 to 300 parts by mass, and more preferably 100 to 200 parts by mass, per 100 parts by mass of the total solid content in the coating material.

[0072] (Other Ingredients) The coating material may contain other components in addition to the above-mentioned limestone, metal hydroxide, and water. Other components include, for example, lightweight aggregates such as perlite, vermiculite, shirasu balloons, glass balloons, vermiculite, perlite, obsidian, fireproof stone, and natural pumice, thickeners, surfactants, pigments, rust inhibitors, and dust inhibitors.

[0073] The coating layer can be formed by applying the above-mentioned coating material to the surface of the polyurethane foam by a method such as spraying or troweling, and then drying. The thickness of the coating layer is, for example, 0.1 to 20 mm, preferably 0.5 to 15 mm, more preferably 1 to 10 mm, and even more preferably 2 to 8 mm, from the viewpoint of adequately protecting the underlying polyurethane foam from heat and from the viewpoint of reducing the weight of the laminate.

[0074] <Method of manufacturing laminate> The method for producing the laminate of the present invention preferably includes the steps of spraying a urethane resin composition containing a polyol, a polyisocyanate, a catalyst, a foaming agent, and a solid phosphorus-based flame retardant onto the surface of a structure to form a polyurethane foam, and forming a coating layer on the polyurethane foam.

[0075] In the step of forming the polyurethane foam, a urethane resin composition containing a polyol, a polyisocyanate, a catalyst, a foaming agent, and a solid phosphorus-based flame retardant is sprayed onto the surface of a structure (substrate) to foam and cure the urethane resin composition to form a polyurethane foam. The structure is not particularly limited, but may be a building, furniture, an automobile, a train, a ship, or the like. Among them, it is preferable to spray the building such as a wall, a ceiling, a roof, or a floor. Spraying can be performed using a spraying device (e.g., A-25 manufactured by GRACO) and a spray gun (e.g., D-gun manufactured by Gasmar). Spraying can be performed, for example, by adjusting the temperature of a polyol composition (preferably a polyol composition containing a polyol, a catalyst, a blowing agent, and a solid phosphorus-based flame retardant) and a polyisocyanate contained in separate containers in a spraying device, colliding and mixing the two at the tip of a spray gun, and turning the mixed liquid into mist by air pressure. The spraying device and spray gun are well known, and commercially available products can be used. In addition, the temperature setting and pressure of the raw liquid can be the same as those for spraying general polyurethane foam.

[0076] In the step of forming a coating layer on the polyurethane foam, a coating material is applied to the polyurethane foam formed on the surface of the structure. Examples of the application method include spraying with a spraying device such as a mortar pump, troweling, etc. After the coating material is applied, it is dried to form a coating layer.

[0077] In the manner described above, a laminate comprising a polyurethane foam and a coating layer laminated on the surface of the polyurethane foam can be produced. The laminate of the present invention has a lower maximum heat release rate and a lower total heat release amount than conventional laminates, and has excellent flame retardancy. EXAMPLES

[0078] The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples in any way.

[0079] Details of each component used in each example and comparative example are as follows.

[0080] [Urethane resin composition] <Polyol> p-Phthalic acid-based polyester polyol (Kawasaki Chemical Industries, Ltd., product name: Maximol RLK-087, hydroxyl value = 200 mg KOH / g)

[0081] <Catalyst> (1) Trimerization catalyst Quaternary ammonium salt: 2,2-dimethylpropanoic acid tetramethylammonium salt (manufactured by Evonik, product name: DABCO TMR7) concentration 45 to 55% by mass Metal catalyst: Potassium 2-ethylhexanoate (manufactured by Evonik, product name: DABCO K-15) concentration 70-80% by mass (2) Urethane catalyst Bismuth trioctate (manufactured by Nitto Kasei, product name: Neostan U-600) concentration 55-58% by mass 1,2-Dimethylimidazole (manufactured by Tosoh Corporation, product name: TOYOCAT (registered trademark)-DM70) concentration: 65 to 75% by mass

[0082] <Liquid flame retardant> Phosphate ester flame retardant Tris(β-chloropropyl)phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: TMCPP)

[0083] <Solid phosphorus-based flame retardant> Red phosphorus (manufactured by Rinkagaku Kogyo Co., Ltd., product name: Nova Excel 140) Polyphosphate: Ammonium polyphosphate (Clariant, product name: AP422) Phosphinic acid salt (Clariant, product name: OP1230)

[0084] <Solid flame retardants other than solid phosphorus-based flame retardants> Zinc borate (Hayakawa Shoji Firebrake ZB)

[0085] <Foaming agent> Water: Ion-exchanged water HFO-1233zd(E) <hydrofluoroolefin> (manufactured by Honeywell, product name: Solstice LBA)

[0086] <Polyisocyanate compounds> 4,4'-Diphenylmethane diisocyanate (4,4'-MDI) (manufactured by Manka Chemical Japan Co., Ltd., product name: PM200)

[0087] [Coating material] <Limestone> Limestone was incorporated into the coating material by blending it with the following Dancoat SF. - Ohashi Chemical Industry Co., Ltd. "Dancoat SF" White cement included

[0088] <Metal hydroxide> Aluminum hydroxide: Armolix "B-325" Magnesium hydroxide: Kyowa Suimag F manufactured by Kyowa Chemical Industry Co., Ltd.

[0089] [Example 1] A polyurethane foam was obtained under the following conditions using a polyol composition prepared by mixing a polyol, a flame retardant, a catalyst, and a blowing agent shown in Table 1, and a polyisocyanate shown in Table 1. The composition of the urethane resin composition obtained by mixing the polyol composition and the polyisocyanate is as shown in Table 1. <Sample preparation conditions> Spray machine: Graco H-25 spray machine Settings (Heater settings) Isocyanate heater: 38℃ Premix heater (for heating polyol composition): 38℃ Hose heater (for heating polyisocyanate and polyol compositions before mixing): 38°C · Base material: gypsum board · Substrate temperature (temperature of the surface to be sprayed): 20℃±1℃

[0090] As described above, a sample was obtained in which polyurethane foam was formed on a gypsum board. The sample was cut from the polyurethane foam side to a size of 10 cm long, 10 cm wide, 3.5 cm thick, including the gypsum board. A part of the cut sample was the gypsum board, and the thickness of the gypsum board was 1.25 cm and the thickness of the polyurethane foam was 2.25 cm in the 3.5 cm thickness. A coating material having the composition shown in Table 1 was applied to the surface of the polyurethane foam of the cut sample, and dried for one week at 25° C. In this manner, a sample for cone calorimeter test was obtained, which included a laminate in which a coating layer was laminated on the surface of a polyurethane foam.

[0091] [Total heat generation, maximum heat generation rate (CCM: cone calorimeter)] The cone calorimeter test sample obtained as described above was subjected to a radiant heat intensity of 50 kW / m in accordance with the ISO-5660 test method. 2 Total heat generated when heated for 10 minutes (MJ / m 2 The maximum heat release rate (kW / m) was also measured when the material was heated for 10 minutes under the same conditions. 2) was measured. (Total heat generation) 〇: Total heat output for 10 minutes is 8MJ / m 2 below ×: Total heat generation for 10 minutes is 8MJ / m 2 Greater than (Maximum heat generation rate) ◎: 20kW / m 2 less than 〇: 20kW / m 2 More than 50kW / m 2 less than ×:50kW / m 2 End

[0092] [Examples 2 to 11, Comparative Examples 1 to 2] A cone calorimeter test sample was prepared in the same manner as in Example 1, except that the composition was changed as shown in Table 1, and the total calorific value and the maximum heat release rate were measured.

[0093] [Table 1]

[0094] The parts by mass of each catalyst are parts by mass of the product.

[0095] It is clear that the laminates of the Examples that satisfy the requirements of the present invention have low total heat generation and maximum heat generation rate, and thus have improved flame retardancy. In contrast, the laminate of Comparative Example 1, which does not contain metal hydroxide in the coating material, has high total heat generation and maximum heat generation rate, and even Comparative Example 2, which has a thicker coating layer than Comparative Example 1, has a high total heat generation. This shows that the laminates of the Comparative Examples that do not satisfy the requirements of the present invention have inferior flame retardancy to the laminates of the Examples.

Claims

1. A laminate comprising a polyurethane foam and a coating layer laminated on a surface of the polyurethane foam, the polyurethane foam contains a red phosphorus-based flame retardant and further contains one or both of a phosphate-containing flame retardant and a boron-based flame retardant; The coating layer comprises limestone and metal hydroxide.

2. The laminate according to claim 1 , wherein the coating layer is formed from a coating material containing limestone, metal hydroxide, and water.

3. 3. The laminate according to claim 1, wherein the metal hydroxide is at least one selected from the group consisting of magnesium hydroxide and aluminum hydroxide.

4. 3. The laminate according to claim 2, wherein the content of the metal hydroxide in the coating material is 3 to 80 mass % based on the total solid content.

5. The laminate according to claim 1 , wherein the polyurethane foam is formed from a urethane resin composition containing a polyol, a polyisocyanate, a catalyst, a blowing agent, and a solid phosphorus-based flame retardant.

6. The laminate of claim 5 , wherein the catalyst comprises a trimerization catalyst.

7. The laminate of claim 6 , wherein the trimerization catalyst comprises a quaternary ammonium salt.

8. 7. The laminate according to claim 5, wherein the catalyst comprises at least one metal catalyst selected from the group consisting of bismuth and tin.

9. The laminate according to claim 5 or 6, wherein the catalyst comprises an imidazole derivative.

10. The laminate according to claim 5 or 6, wherein the urethane resin composition is for spray application.