Laminate

Abstract

The objective is to provide a laminate with high flame retardancy even without substantially containing fillers in the polyurethane foam. [Solution] A laminate comprising a polyurethane foam layer and a coating layer, wherein the polyurethane foam layer is formed from a urethane resin composition containing a polyol, polyisocyanate, hydrofluoroolefin, catalyst, and phosphate ester, the urethane resin composition is for spraying applications, the catalyst contains a quaternary ammonium salt and a bismuth salt, the isocyanate index of the urethane resin composition is 300 or higher, the urethane resin composition is substantially free of fillers, and the coating layer contains a calcium derivative.

Description

[Technical Field]

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

[0002] Polyurethane foam is used in practical applications for insulation and condensation prevention in various structures such as ceilings, roofs, and walls of buildings, including apartment buildings, detached houses, and commercial buildings, due to its excellent thermal insulation properties. 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] In order to improve the fire resistance or flame retardancy of polyurethane foam, it has also been considered to laminate a surface layer on its surface. For example, Patent Document 1 discloses an invention relating to a laminated structure comprising a urethane foam layer containing a filler and a protective layer provided on the urethane foam layer and containing a hydroxyl group component. Patent Document 2 discloses an invention relating to a composite thermal insulation material comprising a sprayed polyurethane foam containing a polyisocyanurate structure and an inorganic coating laminated on the surface of the polyurethane foam. Patent Document 3 discloses an invention relating to a laminate comprising a polyurethane foam containing a solid phosphorus-based flame retardant and a coating layer laminated on the surface of the polyurethane foam, the coating layer containing limestone and metal hydroxide. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2021-079683 [Patent Document 2] Japanese Patent Publication No. 2023-129045 [Patent Document 3] Japanese Patent Publication No. 2024-103295 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Conventionally, in addition to laminating a surface layer onto the surface of the polyurethane foam as described above, other methods have been used to improve fire resistance or flame retardancy, such as increasing the isocyanate index of the urethane resin composition or adding fillers to the polyol composition that constitutes the urethane resin composition. However, when a filler is added to a polyol composition, problems arise such as the so-called caking occurring, where the filler settles during long-term storage of the composition, making it difficult to re-stir the filler, or the workability of the urethane resin composition during spraying deteriorates.

[0006] Therefore, the object of the present invention is to provide a laminate with high flame retardancy even when the polyurethane foam is formed from a urethane resin composition that substantially does not contain fillers. [Means for solving the problem]

[0007] The inventors of the present invention have discovered that the above problems can be solved by laminating a coating material containing a calcium derivative onto a polyurethane foam having a specific structure formed by spraying, and have completed the present invention described below. In other words, the present invention provides the following [1] to

[11] .

[0008] [1] A laminate comprising a polyurethane foam layer and a coating layer laminated on the surface of the polyurethane foam layer, wherein the polyurethane foam layer is a spray foam formed from a urethane resin composition containing a polyol, a polyisocyanate, a hydrofluoroolefin, a catalyst, and a phosphate ester-based flame retardant, the catalyst contains a quaternary ammonium salt and a bismuth salt, the isocyanate index of the urethane resin composition is 300 or more, the urethane resin composition is substantially free of fillers, and the coating layer contains a calcium derivative. [2] The laminate according to [1], comprising a tetramethylammonium salt as the quaternary ammonium salt. [3] The laminate according to [1] or [2], wherein the catalyst comprises an imidazole derivative. [4] The laminate according to any one of [1] to [3], wherein the coating layer comprises at least one selected from the group consisting of aluminum hydroxide, mica, glass fiber, silica, sodium oxide, and aluminum oxide. [5] The laminate according to [4], wherein the coating layer comprises at least one of aluminum hydroxide and glass fibers. [6] The laminate according to [5], wherein the coating layer contains glass fibers. [7] The laminate according to any one of [1] to [6], comprising at least one selected from the group consisting of calcium sulfate, calcium carbonate, and tricalcium silicate as the calcium derivative. [8] The laminate according to any one of [1] to [7], wherein the content of the filler in the urethane resin composition is 3 parts by mass or less per 100 parts by mass of the polyol. [9] The laminate according to any one of [1] to [8], wherein a primer layer is provided between the polyurethane foam layer and the coating material layer, or the coating material layer contains an adhesion promoter.

[10] The laminate according to [9], wherein at least one of the primer layer and the adhesion promoter includes at least one selected from the group consisting of vinyl copolymer resin, acrylic copolymer resin, methacrylic copolymer resin, epoxy resin, rubber resin, silicone resin, and ethylene-vinyl acetate copolymer resin. A urethane resin composition for providing a laminate according to any one of items

[11] [1] to

[10] , wherein the urethane resin composition comprises a polyol, a polyisocyanate, a hydrofluoroolefin, a catalyst, and a phosphate ester-based flame retardant, the catalyst comprises a quaternary ammonium salt and a bismuth salt, the isocyanate index of the urethane resin composition is 300 or more, and the urethane resin composition is substantially filler-free. [Effects of the Invention]

[0009] According to the present invention, even when the polyurethane foam is formed from a urethane resin composition substantially free of a filler, a laminate having high flame retardancy can be provided.

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the laminate of the present invention will be described using embodiments. [Laminate] The laminate of the present invention includes a polyurethane foam layer and a coat material layer laminated on the surface of the polyurethane foam layer. Hereinafter, each component will be described in detail.

[0011] [Polyurethane foam layer] In the present invention, the polyurethane foam layer is a spray foam formed from a urethane resin composition containing a polyol, a polyisocyanate, a hydrofluoroolefin, a catalyst, and a phosphate ester flame retardant. In the present invention, the urethane resin composition substantially does not contain a filler, has an isocyanate index of 300 or more, and the catalyst contains a quaternary ammonium salt and a bismuth salt. The laminate of the present invention includes the polyurethane foam layer having the above configuration and a specific coat material layer described later, so that while improving the workability of the polyurethane foam layer which is a spray foam, the flame retardancy is improved, and even when heated during a fire, ignition is prevented and generation of flames is appropriately prevented, and spread of fire during a fire can be appropriately prevented.

[0012] [Polyol] The polyol is not particularly limited, and examples thereof include polyether polyol, polyester polyol, and the like. From the viewpoint of improving the flame retardancy of the polyurethane foam, it is preferable that the polyol contains a polyester polyol. The polyol may be used alone or in combination of two or more. From the viewpoint of flame retardancy, it is preferable that the amount of polyester polyol be 20 parts by mass or more, more preferably 50 parts by mass or more, even more preferably 80 parts by mass or more, and particularly preferably 100 parts by mass out of 100 parts by mass of polyol.

[0013] The average hydroxyl value of the polyol used in the present invention is preferably 100 to 500 mg KOH / g, more preferably 150 to 450 mg KOH / g, and even more preferably 180 to 400 mg KOH / g, from the viewpoint of improving the flame retardancy of the polyurethane foam. The average hydroxyl value is the hydroxyl value of a single polyol if only one type of polyol is used, and the average value of hydroxyl groups according to the blending ratio of the two or more polyols if two or more types of polyols are used. For example, when using two types of polyols, (d1) and (d2), if the hydroxyl value of polyol (d1) is X1, the mixing ratio is m1, the hydroxyl value of polyol (d2) is X2, and the mixing ratio is m2, then the average hydroxyl value is expressed by the following formula. Note that the mixing ratio is on a mass basis. Average hydroxyl value (mgKOH / g)=X1×(m1 / (m1+m2))+X2×(m2 / (m1+m2)) The hydroxyl value is measured in accordance with JIS K1557-1:2007.

[0014] <Polyester Polyol> The polyester polyol may be a polyester polyol having an aromatic ring or an aliphatic polyester polyol, but when considering the flame retardancy of the resulting polyurethane foam, it is preferable to use a polyester polyol having an aromatic ring. The polyester polyol having an aromatic ring 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. In particular, from the viewpoint of improving the flame retardancy of the polyurethane foam, it is preferable that the polyol includes a phthalic acid-based polyester polyol, which is a condensate of phthalic acid and glycol, and more preferably a p-phthalic acid-based polyester polyol, which is a condensate of p-phthalic acid and glycol. While the glycol is not particularly limited, it is preferable to use a low molecular weight aliphatic glycol known as a component of polyester polyols, such as ethylene glycol, propylene glycol, or diethylene glycol.

[0015] <Polyether polyol> Examples of polyether polyols include polyoxyalkylene polyols obtained by ring-opening addition polymerization of alkylene oxide to an initiator having two or more active hydrogen atoms. Examples of initiators include aliphatic polyhydric alcohols (e.g., glycols such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, neopentyl glycol, cyclohexylene glycol, and cyclohexanedimethanol; triols such as trimethylolpropane and glycerin; tetrafunctional alcohols such as pentaerythritol; highly functional alcohols such as sucrose and sorbitol); aliphatic amines (e.g., alkylenediamines such as ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, and neopentyldiamine; alkanolamines such as monoethanolamine and diethanolamine); and aromatic amines (e.g., aniline, tolylenediamine, xylylenediamine, diphenylmethanediamine, Mannich condensates, etc.). Of these, polyether polyols produced using an initiator having an aromatic ring are polyether polyols having an aromatic ring. For example, polyether polyols produced using an aromatic amine as an initiator are polyether polyols having an aromatic ring. Among polyether polyols having an aromatic ring, tolylenediamine-based polyether polyols and Mannich-based polyether polyols can be suitably used.

[0016] Tolylenediamine-based polyether polyols are tolylenediamine-based polyether polyols manufactured using tolylenediamine as an initiator. The above-mentioned Mannich-type polyether polyols are obtained using the Mannich reaction and are Mannich condensates having two or more hydroxyl groups in the molecule, or polyether polyols obtained by adding alkylene oxide to such Mannich condensates. More specifically, they are Mannich condensates obtained by the Mannich reaction of at least one of phenol and its alkyl-substituted derivatives, formaldehyde and alkanolamines, or polyether polyols obtained by ring-opening addition polymerization of these compounds with at least one of ethylene oxide and propylene oxide.

[0017] (Polyisocyanate) Examples of polyisocyanates include aromatic polyisocyanates, alicyclic polyisocyanates, and aliphatic polyisocyanates. Examples of aromatic polyisocyanates include phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, dimethyldiphenylmethane diisocyanate, triphenylmethane triisocyanate, naphthalene diisocyanate, and polymethylene polyphenyl polyisocyanate (polymeric MDI).

[0018] Examples of alicyclic polyisocyanates include cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and dimethyldicyclohexylmethane diisocyanate. Examples of aliphatic polyisocyanates include methylene diisocyanate, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, and hexamethylene diisocyanate.

[0019] Among these, aromatic polyisocyanates are preferred from the viewpoint of ease of use and availability, diphenylmethane diisocyanate, polymeric MDI, or mixtures thereof are more preferred, with diphenylmethane diisocyanate being even more preferred, and 4,4'-diphenylmethane diisocyanate being particularly preferred. Polyisocyanates may be used individually or as a mixture of two or more.

[0020] In the present invention, the isocyanate index of the urethane resin composition is 300 or higher. If the isocyanate index is less than 300, the flame retardancy of the polyurethane foam layer may not be sufficiently improved, and the flame retardancy of the entire laminate may be insufficient. From this viewpoint, the isocyanate index is preferably 350 or higher, and more preferably 450 or higher. Furthermore, the isocyanate index is not particularly limited, but is preferably 1,000 or less, more preferably 800 or less, and even more preferably 600 or less. When the isocyanate index is below the above upper limit, flame retardancy that is sufficiently commensurate with the manufacturing cost can be obtained.

[0021] The isocyanate index can be calculated using the following method. Isocyanate Index = Equivalents of polyisocyanate ÷ (Equivalents of polyol + Equivalents of water) × 100 Here, each equivalent number can be calculated as follows: • Equivalent weight of polyisocyanate = Amount of polyisocyanate used (g) × NCO content (mass%) / Molecular weight of NCO (moles) × 100 • Equivalent weight of polyol = OHV × Amount of polyol used (g) ÷ Molecular weight of KOH (millimoles) OHV is the hydroxyl value (mgKOH / g) of a polyol. • Equivalent amount of water = Amount of water used (g) / Molecular weight of water (moles) × Number of OH groups in water In the above formulas, the molecular weight of NCO is 42 moles, the molecular weight of KOH is 56,100 millimoles, the molecular weight of water is 18 moles, and the number of OH groups in water is 2.

[0022] (catalyst) In the present invention, the urethane resin composition contains at least a quaternary ammonium salt and a bismuth salt as catalysts. By including these catalysts, excellent foaming properties can be imparted to the polyurethane foam layer.

[0023] <Quaternary ammonium salts> Quaternary ammonium salts are generally trimerizing catalysts, such as tetramethylammonium salt, methyltriethylammonium salt, ethyltrimethylammonium salt, propyltrimethylammonium salt, butyltrimethylammonium salt, pentyltrimethylammonium salt, hexyltrimethylammonium salt, heptyltrimethylammonium salt, octyltrimethylammonium salt, nonyltrimethylammonium salt, decyltrimethylammonium salt, undecyltrimethylammonium salt, dodecyltrimethylammonium salt, tridecyltrimethylammonium salt, tetradecyltrimethylammonium salt, heptadecyltrimethylammonium salt, and he Examples include aliphatic ammonium salts such as xadecyltrimethylammonium salt, heptadecyltrimethylammonium salt, and octadecyltrimethylammonium salt; hydroxyammonium salts such as (2-hydroxypropyl)trimethylammonium salt, hydroxyethyltrimethylammonium salt, trimethylaminoethoxyethanol salt, and N-(2-hydroxyethyl)-N-(2-hydroxypropyl)-N,Ndimethylammonium salt; and alicyclic ammonium salts such as 1-methyl-1-azania-4-azabicyclo[2,2,2]octanium salt, 1,1-dimethyl-4-methylpiperidinium salt, 1-methylmorpholinium salt, and 1-methylpiperidinium salt. Among these, aliphatic ammonium salts and hydroxyammonium salts are preferred, and at least one of triethylmethylammonium salt, hydroxybutyltrimethylammonium salt, tetramethylammonium salt, and hydroxyammonium salt is more preferred, with tetramethylammonium salt being even more preferred.

[0024] Furthermore, examples of quaternary ammonium salts include quaternary ammonium carboxylates. The carboxylic acid in the quaternary ammonium carboxylate may have one or more carbon atoms, but it is preferable that it has two or more carbon atoms. The carboxylic acid is preferably an aliphatic carboxylic acid, and more preferably a saturated aliphatic carboxylic acid. The number of carbon atoms in the carboxylic acid is, for example, 20 or less, but is preferably 12 or less, and more preferably 8 or less. The carboxylic acid may be linear or have a branched structure, but it is preferable that it has a branched structure. If it has a branched structure, steric hindrance tends to reduce its reactivity with blowing agents such as hydrofluoroolefins.

[0025] Suitable specific examples of carboxylic acids in quaternary ammonium carboxylates include 2-ethylhexanoic acid, 2,2-dimethylpropanoic acid, acetic acid, and formic acid. Among these, at least one selected from acetic acid and 2,2-dimethylpropanoic acid is preferred, and 2,2-dimethylpropanoic acid is more preferred.

[0026] Suitable examples of quaternary ammonium carboxylates include tetramethylammonium acetate, tetramethylammonium 2,2-dimethylpropanoate, triethylmethylammonium 2-ethylhexanoate, hydroxybutyltrimethylammonium 2-ethylhexanoate, acetate of N-(2-hydroxyethyl)-N-(2-hydroxypropyl)-N,Ndimethylammonium, and 2-ethylhexanoate of N-(2-hydroxyethyl)-N-(2-hydroxypropyl)-N,Ndimethylammonium. Among these, at least one selected from tetramethylammonium acetate and tetramethylammonium 2,2-dimethylpropanoate is preferred, and tetramethylammonium 2,2-dimethylpropanoate is more preferred, from the viewpoint of facilitating the formation of isocyanurate bonds by the trimer of polyisocyanate and facilitating the imparting of excellent flame retardancy to polyurethane foam. In this invention, quaternary ammonium salts may be used alone or in combination of two or more types.

[0027] The content of quaternary ammonium salt in the urethane resin composition is preferably 1.5 to 15 parts by mass, more preferably 2 to 10 parts by mass, and even more preferably 2.5 to 8 parts by mass, per 100 parts by mass of polyol. When the quaternary ammonium salt content is within the above range, it becomes easier to impart excellent flame retardancy to the polyurethane foam layer, and the laminate becomes less likely to ignite.

[0028] <Bismuth salt> Bismuth salts are generally urethane catalysts that promote urethane reactions. Examples of bismuth salts include salts of trivalent bismuth with organic acids, specifically bismuth triacetate, bismuth tripionate, bismuth triheptanate, bismastris(2-ethylhexanoate), bismastris(neodecanate), bismuth trilaurate, bismastriolate, and bismuth tristearate. These can be used individually or in combination of two or more. Among the above, bismastris(2-ethylhexanoate) and bismastris(neodecanate) are preferred due to their high catalytic effectiveness and availability, with bismastris(2-ethylhexanoate) being more preferred. In this invention, bismuth salts may be used alone or in combination of two or more types.

[0029] The bismuth salt content in the urethane resin composition is preferably 0.1 to 5 parts by mass, more preferably 0.5 to 3 parts by mass, and even more preferably 1 to 2 parts by mass, per 100 parts by mass of polyol. When the bismuth salt content is within the above range, it becomes easier to impart excellent flame retardancy to the polyurethane foam layer, and the laminate becomes less likely to ignite.

[0030] <Imidazole derivatives> Preferably, the catalyst further contains an imidazole derivative. Imidazole derivatives are generally urethane catalysts that promote the urethane reaction. By including an imidazole derivative, the decomposition of hydrofluoroolefin is prevented, resulting in good foaming properties. Furthermore, the reaction rate can be kept above a certain level, improving the workability when spraying the flame-retardant urethane resin composition.

[0031] As described above, imidazole derivatives are less affected by hydrofluoroolefins and facilitate the reaction between polyols and polyisocyanates while increasing the stability of the urethane resin composition. Therefore, by containing imidazole derivatives, the reactivity of polyols and polyisocyanates in the urethane resin composition is enhanced, resulting in even better foaming properties. The imidazole derivative is preferably an imidazole in which the 1st and 2nd positions are independently substituted 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. A suitable specific example of an imidazole derivative is represented by the following general formula (1).

[0032] [ka] (In general formula (1), R 4 and R 5 Each of these independently represents an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms.

[0033] R in general formula (1) 4 and R 5 Each of these 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 alkenyl group may each be linear or have a branched structure. Specific examples of alkyl groups include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, pentyl group, neopentyl group, isopentyl group, sec-pentyl group, hexyl group, heptyl group, octyl group, and the like. Specific examples of the alkenyl group include a vinyl group, 1-propenyl group, allyl group, isopropenyl group, 1-butenyl group, 2-butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, and the like. R 4 and R 5 When the number of carbon atoms of the alkyl group or alkenyl group of R and R is at least the lower limit value, the steric hindrance becomes large and it is less likely to be affected by a foaming agent such as hydrofluoroolefin, which is preferable. On the other hand, when 4 the number of carbon atoms of the alkyl group of R and R 5 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 4 and R 5 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 still more preferably a methyl group.

[0034] Examples of the imidazole derivative represented by the general formula (1) include 1,2-dimethylimidazole, 1-ethyl-2-methylimidazole, 1-methyl-2-ethylimidazole, 1,2-diethylimidazole, and 1-isobutyl-2-methylimidazole. Among them, from the viewpoints of improving the activity of the catalyst in the presence of hydrofluoroolefin and allowing the reaction to proceed rapidly, 1,2-dimethylimidazole and 1-isobutyl-2-methylimidazole are preferable. Further, from the viewpoint of further enhancing the stability, 1,2-dimethylimidazole is more preferable. In the present invention, the imidazole derivative may be used alone or in combination of two or more.

[0035] The content of the imidazole derivative in the urethane resin composition is preferably 1 to 10 parts by mass, more preferably 2 to 8 parts by mass, and still more preferably 3 to 5 parts by mass with respect to 100 parts by mass of the polyol. When the imidazole derivative content is within the above range, it becomes easier to impart excellent flame retardancy to the polyurethane foam layer, and the laminate becomes less likely to ignite.

[0036] <Potassium salts> The urethane resin composition preferably further contains a potassium salt as a catalyst. Potassium salts are generally used as trimerizing catalysts. Examples of potassium salts include potassium carboxylates. The carboxylic acid in the potassium carboxylate may have 1 or more carbon atoms, but it is preferable that it has 5 or more carbon atoms. The carboxylic acid is preferably an aliphatic carboxylic acid, and more preferably a saturated aliphatic carboxylic acid. The number of carbon atoms in the carboxylic acid is, for example, 20 or less, but is preferably 12 or less, and more preferably 8 or less. The carboxylic acid may be linear or have a branched structure, but it is preferable that it has a branched structure. If it has a branched structure, steric hindrance tends to reduce its reactivity with blowing agents such as hydrofluoroolefins.

[0037] Potassium carboxylate salts are preferably those represented by the following general formula (2). Potassium carboxylate salts represented by the following general formula (2) have appropriate steric hindrance, which can suppress the reaction that decomposes the foaming agent and also prevent a decrease in catalytic activity.

[0038] [ka] (In general formula (2), R 1 and R 2 Each of these independently represents an alkyl group, and R 3 represents a hydrogen atom or an alkyl group. Also, K + (This represents potassium ions.)

[0039] R in general formula (2) 1 and R 2Each of these independently represents an alkyl group, specifically, alkyl groups having 1 to 6 carbon atoms are preferred, alkyl groups having 1 to 4 carbon atoms are more preferred, and alkyl groups having 1 to 2 carbon atoms are even more preferred. The alkyl group may be linear or have a branched structure. R 1 , R 2 If the number of carbon atoms is greater than or equal to the lower limit, steric hindrance increases, which can suppress the reaction that decomposes hydrofluoroolefins. On the other hand, R 1 , and R 2 If the number of carbon atoms is below the aforementioned upper limit, steric hindrance does not become too large, thus preventing the reaction from becoming slow. Also, R 3 R represents a hydrogen atom or an alkyl group, with a hydrogen atom being preferred. 3 If the alkyl group is an alkyl group, it is preferably one to six carbon atoms, more preferably one to four carbon atoms, and even more preferably one to two carbon atoms.

[0040] Preferred specific examples of carboxylic acids in potassium carboxylic acid salts include at least one selected from the group consisting of 2-ethylhexanoic acid, 2,2-dimethylpropanoic acid, acetic acid, and formic acid. Furthermore, carboxylic acids as shown in the above general formula (2) are preferred, and among these, 2,2-dimethylpropanoic acid and 2-ethylhexanoic acid are more preferred. In this invention, potassium carboxylate salts may be used alone or in combination of two or more types.

[0041] The potassium carboxylate content in the urethane resin composition is preferably 1 to 10 parts by mass, more preferably 2 to 8 parts by mass, and even more preferably 3 to 5 parts by mass, per 100 parts by mass of polyol.

[0042] The urethane resin composition of the present invention may contain catalysts other than the quaternary ammonium salts, bismuth salts, imidazole derivatives, and potassium salts described above, as long as it achieves the effects of the present invention.

[0043] (Foaming agent) In the present invention, the urethane resin composition contains hydrofluoroolefin (hereinafter also referred to as "HFO"). HFO may be included as a blowing agent. Among blowing agents, HFO has high stability, does not easily decrease catalytic activity, and has a low environmental impact.

[0044] Suitable HFOs as blowing agents include fluoroalkenes with approximately 3 to 6 carbon atoms. Alternatively, the HFO may be a hydrochlorofluoroolefin containing a chlorine atom, and therefore may also be a chlorofluoroalkene with approximately 3 to 6 carbon atoms. Examples of HFOs include trifluoropropene, tetrafluoropropene such as HFO-1234, pentafluoropropene such as HFO-1225, chlorodifluoropropene, chlorotrifluoropropene such as HFO-1233, and chlorotetrafluoropropene. More specifically, 3,3,3-trifluoropropene (HFO-1243zf), trans-1,3,3,3-tetrafluoropropene (HFO-1234ze(E)), cis-1,3,3,3-tetrafluoropropene (HFO-1234ze(Z)), 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,1,3,3-tetrafluoropropene, cis-1,3,3,3-tetrafluoropropene (HFO-1234ze(Z)), and trans-1,2,3,3,3-pene. Examples include tafluoropropene (HFO-1225ye(E)), cis-1,2,3,3,3-pentafluoropropene (HFO-1225ye(Z)), 1,1,3,3,3-pentafluoropropene (HFO-1225zc), 1,1,2,3,3-pentafluoropropene (HFO-1225yc), trans-1-chloro-3,3,3-trifluoropropene (HFO-1233zd(E)), and 1,1,1,4,4,4-hexafluorobuto-2-ene (HFO-1336mzz). Among these, HFO-1233zd(E) is preferred.

[0045] The HFO content is preferably 20 to 55 parts by mass, more preferably 25 to 50 parts by mass, and even more preferably 30 to 45 parts by mass, per 100 parts by mass of polyol.

[0046] The urethane resin composition may contain blowing agents other than HFO. For example, organic physical blowing agents such as water, low-boiling hydrocarbons such as propane, butane, pentane, hexane, heptane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, and cycloheptane, chlorinated aliphatic hydrocarbon compounds such as dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, and isopentyl chloride, ether compounds such as diisopropyl ether, or mixtures thereof, or inorganic physical blowing agents such as nitrogen gas, oxygen gas, argon gas, and carbon dioxide gas can be used. Furthermore, one or more of the above-mentioned foaming agents may be used. In the urethane resin composition of the present invention, it is preferable to use the above-mentioned HFO in combination with other foaming agents. For example, HFO may be used in combination with water, oxygen gas, or carbon dioxide gas, which have excellent handling properties. Water is particularly preferred from the viewpoint of adjusting the isocyanate index and from the viewpoint of ease of handling.

[0047] The water content is preferably 0.05 to 1 part by mass, more preferably 0.1 to 0.5 parts by mass, and even more preferably 0.15 to 0.3 parts by mass, per 100 parts by mass of polyol.

[0048] (Phosphate ester-based flame retardant) The urethane resin composition contains a phosphate ester-based flame retardant. The inclusion of a phosphate ester-based flame retardant makes it easier to impart excellent flame retardancy to the polyurethane foam without excessively increasing the viscosity of the urethane resin composition. Phosphate ester-based flame retardants are typically liquid flame retardants, becoming liquid at room temperature (25°C) and normal pressure (1 atm).

[0049] 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.

[0050] 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.

[0051] 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 urethane resin composition and from the viewpoint of improving the flame retardancy of the polyurethane foam, and halogen-containing phosphate esters such as tris(β-chloropropyl) phosphate are more preferred.

[0052] The content of the phosphate ester-based flame retardant in the urethane resin 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 30 to 60 parts by mass, per 100 parts by mass of polyol. If the content of phosphate ester-based flame retardants is above these lower limits, the viscosity of the urethane resin composition can be lowered, and flame retardancy can be imparted to the polyurethane foam without substantially including fillers such as solid flame retardants. Furthermore, if the content of phosphate ester-based flame retardants is below these upper limits, foaming is not inhibited, making it easier to manufacture the polyurethane foam layer.

[0053] (Foam stabilizer) The urethane resin composition 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 (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 (Toray Dow Corning), S-824-02 (Nippon Unicar), SZ-1704 (Nippon Unicar), F501 (Shin-Etsu Chemical Co., Ltd.), and SF-2937F (Dow Toray). The amount of foam stabilizer is not particularly limited, but is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 8 parts by mass, and even more preferably 1 to 5 parts by mass per 100 parts by mass of polyol.

[0054] (Other ingredients) In addition to the above, the urethane resin composition may contain, as necessary and within limits that do not impair its purpose, one or more additives selected from phenolic, amine, and sulfur-based antioxidants, heat stabilizers, metal damage inhibitors (metal deactivators), antistatic agents, stabilizers, crosslinking agents, lubricants, softeners, plasticizers, pigments, tackifying resins, polybutene, petroleum resins, and other tackifying agents.

[0055] The urethane resin composition is substantially filler-free. By being substantially filler-free, workability can be improved. In this specification, "substantially filler-free" means that the filler content in the urethane resin composition is 5 parts by mass or less per 100 parts by mass of polyol, preferably 3 parts by mass or less, more preferably 1 part by mass or less, and even more preferably 0 parts by mass. Fillers are components that remain solid in urethane resin compositions without dissolving in polyols and polyisocyanates. Examples of fillers include solid flame retardants that are solid at room temperature (25°C) and atmospheric pressure (1 atm), such as red phosphorus-based flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, and metal hydroxides, as well as inorganic fillers other than solid flame retardants. However, the catalysts mentioned above are not included in fillers. Examples of inorganic fillers include silica, diatomaceous earth, alumina, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, basic magnesium carbonate, calcium carbonate, magnesium carbonate, barium carbonate, dawsonite, hydrotalcite, calcium sulfate, barium sulfate, potassium salts such as calcium silicate, talc, clay, mica, montmorillonite, bentonite, activated clay, sepiolite, imogolite, sericite, glass beads, silica powder, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon powder, charcoal powder, various metal powders, potassium titanate, magnesium sulfate, lead zirconate titanate, aluminum porate, molybdenum sulfide, silicon carbide, various magnetic powders, and fly ash.

[0056] The urethane resin composition of the present invention hardens through a reaction between a polyol and a polyisocyanate, and therefore its viscosity changes over time. For this reason, it is preferable to divide the urethane resin composition into two or more parts before use to prevent it from reacting and hardening, and then combine the two or more parts into one when using the urethane resin composition.

[0057] When dividing a urethane resin composition into two or more parts, the curing reaction should be initiated only after mixing the components of the divided urethane resin composition, rather than each component alone. Preferably, the urethane resin composition is divided into one and two parts to form a two-part curing type. In this case, the urethane resin composition is usually divided into a polyol composition containing a polyol compound and a polyisocyanate composition containing a polyisocyanate.

[0058] The hydrofluoroolefins (HFOs), quaternary ammonium salts, bismuth salts, and phosphate ester-based flame retardants described above, as well as blowing agents other than HFOs, catalysts other than quaternary ammonium salts and bismuth salts, foam stabilizers, and other additives that may be added as needed, may be contained in the polyol composition. These may also be contained in the polyisocyanate composition, or may be provided separately from the polyol composition and the polyisocyanate composition, but it is preferable that they be contained in the polyol composition. In other words, the polyol composition is preferably a polyol premix containing a polyol, a quaternary ammonium salt, a bismuth salt, and a phosphate ester-based flame retardant, as well as a blowing agent other than HFO, a catalyst other than the quaternary ammonium salt and bismuth salt, a foam stabilizer, and other additives as needed, and the urethane resin composition of the present invention is preferably a mixture of the polyol premix and a polyisocyanate. Furthermore, it is preferable that the volume of the polyol premix (liquid 1) and the polyisocyanate (liquid 2) mixed with the polyol premix are substantially the same. Specifically, the volume ratio of polyisocyanate to polyol premix is ​​preferably 0.8 to 1.2, more preferably 0.9 to 1.1, and even more preferably 0.95 to 1.05.

[0059] The urethane resin composition begins to react when its components are mixed, such as by mixing liquid 1 and liquid 2. Over time, the viscosity increases, curing and foaming progress, and it loses its fluidity, forming a polyurethane foam layer. The urethane resin composition is usually allowed to cure and foam by being left at room temperature (for example, around 10-40°C), but heating may be used if necessary.

[0060] In the present invention, the polyurethane foam layer is a spray foam formed from the above-described urethane resin composition. Since the urethane resin composition substantially does not contain fillers, it is possible to form a polyurethane foam layer on a structure with excellent workability. In this invention, for example, a polyurethane resin composition is sprayed onto the surface of a structure, and curing and foaming are carried out on the surface of the structure to form a polyurethane foam layer on the surface of the structure. The structure is not particularly limited, but examples include buildings, furniture, automobiles, trains, ships, etc., but among these, building structures such as walls, ceilings, roofs, and floors are preferred. Spraying can be carried out using a spraying device (e.g., GRACO A-25) and a spray gun (e.g., Gasmar D-gun). Spraying can be carried out, for example, by adjusting the temperature of the polyol premix and polyisocyanate in separate containers within the spraying device, mixing them by collision at the tip of the spray gun, and atomizing the mixture with air pressure. The spraying equipment and spray gun are well-known and commercially available products can be used. Furthermore, the stock solution temperature settings, pressure, etc., can be adapted to general polyurethane foam spraying conditions.

[0061] The thickness of the polyurethane foam layer is not particularly limited, but is preferably 2 to 150 mm, more preferably 5 to 80 mm, and even more preferably 8 to 50 mm. Having a thickness above these lower limits makes it easier to improve various properties of the polyurethane foam layer, such as flame retardancy. Conversely, keeping the thickness below these upper limits prevents the polyurethane foam layer from becoming unnecessarily thick.

[0062] (Coating layer) The coating layer constituting the laminate of the present invention contains a calcium derivative as a coating material. By including the calcium derivative, the flame retardancy of the coating layer is improved, and even if the polyurethane foam layer does not substantially contain fillers, the flame retardancy of the laminate is improved, preventing the laminate from igniting in the event of a fire. The coating layer is preferably laminated over the entire surface of the polyurethane foam layer, but it may also be laminated only on a portion of the surface of the polyurethane foam layer.

[0063] Examples of calcium derivatives include calcium gluconate, calcium carbonate, calcium sulfate, tricalcium silicate, calcium hydroxide, pearl calcium, calcium lactate, milk calcium, shell calcium, calcium acetate, calcium nitrate, calcium bicarbonate, and calcium sulfite. Among these, it is preferable to include at least one selected from calcium sulfate, calcium carbonate, and tricalcium silicate, and more preferably at least one selected from calcium carbonate and tricalcium silicate. Calcium derivatives may be used individually or in combination of two or more.

[0064] The calcium derivative content in the coating layer is preferably 20-90% by mass, more preferably 30-85% by mass, and even more preferably 40-80% by mass, based on the total amount of the coating layer. When the calcium derivative content is above the lower limit, the flame retardancy of the laminate tends to improve. Furthermore, when the calcium derivative content is below the upper limit, the coatability and other properties improve, and it becomes easier to uniformly form the coating layer on the polyurethane foam layer.

[0065] The coating layer preferably further contains inorganic fillers other than calcium derivatives such as aluminum hydroxide, mica, glass fibers, silica, sodium oxide, and aluminum oxide, and more preferably contains at least one of aluminum hydroxide and glass fibers, and even more preferably contains glass fibers. These inorganic fillers may be used individually or in combination of two or more. By including the inorganic filler, particularly glass fiber, in the coating layer, cracking of the coating layer during a fire is suppressed, preventing flames and heat from penetrating through the cracks. Furthermore, the inclusion of aluminum hydroxide can lower the initial and total heat generation, making it easier to improve the flame retardancy of the laminate. The glass fiber content in the coating layer is not particularly limited, but is preferably 0.3 to 40% by mass, more preferably 0.5 to 30% by mass, and even more preferably 1 to 20% by mass, based on the total amount of the coating layer.

[0066] The coating layer preferably contains a binder. Using a binder improves the mechanical strength of the coating layer. An inorganic binder may be used. Using an inorganic binder allows the coating layer to be an inorganic coating layer. Using an inorganic binder further improves fire resistance. The inorganic binder is not particularly limited, but examples include water-hardening cement and dolomite plaster. Examples of the water-hardening cement include Portland cement, white cement, blast furnace cement, silica cement, and fly ash cement. Among these, white cement and dolomite plaster are preferred as binders, and white cement is more preferred from the viewpoint of improving design aesthetics. One type of binder may be used alone, or two or more types may be used in combination. The binder content in the coating layer is not particularly limited, but is, for example, 5 to 60% by mass, preferably 10 to 50% by mass. If the binder content is above these lower limits, the mechanical strength of the coating layer is improved. If the binder content is below these upper limits, thermal distortion during heating is less likely to occur, making it easier to prevent damage.

[0067] The coating layer may contain an adhesion promoter. By including an adhesion promoter, the adhesion strength of the coating layer to the foam layer can be increased, allowing the coating layer to be directly laminated onto the polyurethane foam layer. For example, after the laminate is applied to the surface of a building, the coating layer becomes less likely to detach, and it becomes easier to maintain good flame retardancy. Examples of adhesion promoters include vinyl copolymer resins, acrylic copolymer resins, methacrylic copolymer resins, epoxy resins, rubber resins, silicone resins, and organic adhesion promoters such as ethylene-vinyl acetate copolymer resins. The inclusion of these components in the adhesion promoter improves the adhesion of the coating layer. Among these, components obtained by polymerizing double bonds, such as vinyl copolymer resins, acrylic copolymer resins, methacrylic copolymer resins, and ethylene-vinyl acetate copolymer resins, are preferred. Adhesion-enhancing agents may be used individually or in combination of two or more types.

[0068] The content of the adhesion promoter in the coating layer is not particularly limited, but is preferably 1 to 50% by mass, more preferably 3 to 40% by mass, and even more preferably 5 to 30% by mass, based on the total amount of the coating layer. If the content of the adhesion promoter is above the lower limit, sufficient adhesion is easily imparted to the coating layer. If the content of the adhesion promoter is below the upper limit, the applicability is improved, and it becomes easier to form a uniform coating layer on the polyurethane foam layer. In addition to the components mentioned above, the coating layer may also contain other additives such as pigments, rust inhibitors, and dust inhibitors.

[0069] The thickness of the coating layer is not particularly limited, but is preferably 20 mm or less, more preferably 15 mm or less, even more preferably 10 mm or less, and even more preferably 5 mm or less. When the thickness of the coating layer is below a certain level, it becomes easier to prevent at least a portion of the coating layer from detaching from the polyurethane foam layer due to the weight of the coating layer itself after the lamination is constructed. Furthermore, from the viewpoint of flame retardancy, the thickness of the coating layer is preferably 1 mm or more, and more preferably 2 mm or more.

[0070] The coating layer can be formed by applying a composition containing a calcium derivative (hereinafter also referred to as the "coating material raw material composition"), or a mixture of the coating material raw material composition and water, to the surface of the polyurethane foam layer by methods such as spraying or troweling, and then drying it. As described above, the coating material raw material composition may optionally contain inorganic fillers, binders, adhesion promoters, and other additives in addition to the calcium derivative. If the laminate includes a primer layer as described later, it is preferable to form the coating layer on the surface of the primer layer opposite to the surface in contact with the polyurethane foam layer. The mixing ratio of the above coating material raw material composition to water is, on a mass basis, preferably 40 to 400 parts by mass, more preferably 60 to 300 parts by mass, and more preferably 70 to 250 parts by mass, per 100 parts by mass of water (hereinafter, the mixing ratio of the coating material raw material composition to 100 parts by mass of water is also referred to as "coating material raw material composition / water"). When the coating material raw material composition / water is within the above range, for example, the viscosity of the mixture of the coating material raw material composition and water becomes suitable for application, making it easier to form a uniform coating layer on the polyurethane foam layer.

[0071] Commercially available products may be used as the coating material raw material composition. Specifically, products such as "Dancoat SF," "Dancoat A," and "Dancoat 5" manufactured by Ohashi Chemical Industry Co., Ltd., "Kikusui Non-combustible Coat" manufactured by Kikusui Chemical Industry Co., Ltd., and "Dantheravon #" manufactured by SK Kaken Co., Ltd. can be used.

[0072] (Primer layer) The coating layer may be formed directly on the surface of the polyurethane foam layer, but the laminate of the present invention may also include a primer layer between the polyurethane foam layer and the coating layer. By including a primer layer, the primer layer acts as an adhesive, making it less likely for the coating layer to detach from the polyurethane foam layer. The primer components that can be used as a primer layer are the same as those used in the adhesion promoters described above, so a detailed explanation is omitted. Additionally, additives may be added to the primer components as appropriate. The thickness of the primer layer is not particularly limited, but is preferably 0.01 to 5 mm, more preferably 0.05 to 3 mm, and even more preferably 0.1 to 1 mm. The primer layer can be formed by applying the primer components described above onto the polyurethane foam layer and allowing them to dry as appropriate. The primer components can be diluted with a solvent or water as appropriate before being applied onto the polyurethane foam layer.

[0073] [Method for manufacturing laminates] The laminate of the present invention can be manufactured, for example, by a manufacturing method that includes the steps of spraying the above-described urethane resin composition onto the surface of a structure to form a polyurethane foam layer, and forming a coating material layer on the polyurethane foam layer. The manufacturing method may also include the step of forming a primer layer on the polyurethane foam layer, in which case the coating material layer should be formed on the primer layer. Details of each step are as described above, so their explanation will be omitted here.

[0074] [Urethane resin composition] The present invention can also provide a urethane resin composition for providing the above-described laminate. The urethane resin composition comprises a polyol, a polyisocyanate, a hydrofluoroolefin, a catalyst, and a phosphate ester-based flame retardant, has an isocyanate index of 300 or higher, and is substantially free of fillers. As the components and isocyanate indices of the urethane resin composition are as described above, a detailed explanation of these will be omitted. [Examples]

[0075] The present invention will be described in more detail below with reference to examples, but the present invention is not limited in any way by these examples.

[0076] [Materials used] (Polyisocyanate) • 4,4'-Diphenylmethane diisocyanate (4,4'-MDI) (manufactured by Manka Chemical Japan, product name: PM200)

[0077] (Polyol) • p-phthalate polyester polyol (manufactured by Kawasaki Chemical Industries, Ltd., product name: Maximol RLK-087, hydroxyl value = 200 mg KOH / g)

[0078] (Liquid flame retardant) • Phosphate ester: Tris(β-chloropropyl) phosphate (manufactured by Daihachi Chemical Co., Ltd., product name: TMCPP)

[0079] (catalyst) • Trimerization catalyst 1: Quaternary ammonium salt, tetramethylammonium 2,2-dimethylpropanoate (manufactured by Air Products, product name: DABCO(registered trademark) TMR7), concentration 45-55% by mass Trimerization catalyst 2: Quaternary ammonium salt, N-(2-hydroxyethyl)-N-(2-hydroxypropyl)-N,N-dimethylammonium acetate (manufactured by Kao Corporation, product name: Kaolizer No. 410), concentration 100% by mass Trimerization catalyst 3: Quaternary ammonium salt, 2-ethylhexanoate of N-(2-hydroxyethyl)-N-(2-hydroxypropyl)-N,N-dimethylammonium (manufactured by Kao Corporation, product name: Kaolizer No. 420), concentration 100% by mass • Trimerization catalyst 4: Quaternary ammonium salt, tetramethylammonium acetate (manufactured by Tosoh Corporation, product name: TOYOCAT(registered trademark)-TRX), concentration 60-70% by mass • Trimerization catalyst 5: Metal catalyst, potassium 2-ethylhexanoate (manufactured by Air Products, product name: DABCO(registered trademark) K-15), concentration 70-80% by mass • Urethane catalyst 1: Bismuth salt, bismastris (2-ethylhexanoate) (manufactured by Nitto Chemical Co., Ltd., product name: Neostan U-600), concentration 55-58% by mass • Urethane catalyst 2: Imidazole derivative, 1,2-dimethylimidazole (TOYOCAT®-DM70, manufactured by Tosoh Corporation), concentration 65-75% by mass

[0080] (Foaming agent) ·water • Hydrofluoroolefin (HFO), trans-1-chloro-3,3,3-trifluoropropene (manufactured by Honeywell Japan, product name: Soltis LBA)

[0081] (Coating material raw material composition) • Manufactured by Ohashi Chemical Industry Co., Ltd., product name "Dancoat A", an inorganic coating material raw material composition containing calcium carbonate and glass fiber. • Kikusui Chemical Industry Co., Ltd., product name "Kikusui Non-combustible Coat", inorganic coating material raw material composition containing tricalcium silicate and glass fiber. • SK Chemical Co., Ltd., product name "Dantherabon#", inorganic coating material raw material composition containing calcium carbonate, tricalcium silicate, and glass fiber.

[0082] [Measurement and evaluation methods for each physical property] (Ignitability) In the cone calorimeter test described later, ignition properties were evaluated based on whether or not the sample ignited. A "○" was used if the sample did not ignite, and a "×" if it did ignite.

[0083] (Flame retardant) The cone calorimeter test samples obtained in each example and comparative example were subjected to a radiant thermal intensity test of 50 kW / m² in accordance with the ISO-5660 test method. 2 Total heat output (MJ / m²) when heated for 10 minutes 2 The flame retardancy was evaluated based on the following criteria. The surface with the coating layer was positioned to face the heater used in the cone calorimeter test. The evaluation criteria are as follows: <Evaluation Criteria> 〇: Total heat generation over 10 minutes is 0 MJ / m³ 2 More than 5MJ / m 2 less than △: Total heat generation over 10 minutes is 5 MJ / m³ 2 More than 8MJ / m 2 less than ×: Total heat output over 10 minutes is 5 MJ / m³ 2 Larger than

[0084] (judgement) The overall evaluation was conducted based on the following evaluation criteria. <Evaluation Criteria> ○: Both ignition properties and flame retardancy were evaluated as "△" or higher. ×: At least one of the evaluation results for ignition properties and flame retardancy was "×".

[0085] [Example 1] A polyurethane foam was obtained using a urethane resin composition prepared by mixing a polyol composition containing a polyol, a liquid flame retardant, a catalyst, and a blowing agent, according to the formulations shown in Table 1, with a polyisocyanate, under the following conditions. (Sample preparation conditions) • Spraying machine: Graco H-25 spraying device • Settings (Heater settings) Isocyanate heater: 38℃ Premix heater (for heating polyol compositions): 38℃ Hose heater (for pre-mixing heating of polyisocyanate and polyol compositions): 38°C • Base material: Gypsum board • Substrate temperature (temperature of the surface to be sprayed): 20℃±1℃

[0086] As described above, a sample was obtained in which polyurethane foam was formed on a gypsum board. This sample was cut out from the polyurethane foam side to include the gypsum board, with dimensions of 10 cm in length, 10 cm in width, and 3.5 cm in thickness. A portion of the cut-out sample was gypsum board, with 1.25 cm of the gypsum board and 2.25 cm of the polyurethane foam being the total thickness of 3.5 cm. Next, the coating material raw material compositions listed in Table 1 and water were mixed at a ratio of 100 / 100 (coating material raw material composition / water) by mass. The resulting mixture was applied by trowel to the side of the polyurethane foam layer opposite to the side in contact with the gypsum board, and then dried at 25°C for two weeks to form a coating material layer. The thickness of the coating material layer after drying was as shown in Table 1. In this way, a sample for cone calorimeter testing was obtained, which included a laminate in which a coating material layer was laminated on the surface of a polyurethane foam.

[0087] [Examples 2-15] A sample for cone calorimeter testing was prepared in the same manner as in Example 1, except that the composition of the urethane resin composition, the type of coating material raw material composition, and the thickness of the coating material layer after drying were changed as shown in Table 1.

[0088] [Comparative Examples 1-2] A sample for cone calorimeter testing was prepared in the same manner as in Example 1, except that the composition of the urethane resin composition was changed as shown in Table 1, and a coating layer was not formed by not applying the coating material raw material composition.

[0089] [Table 1] *The numbers in parentheses in the flame retardancy column of Table 1 represent the measured total calorific value measured by a cone calorimeter test, and the unit is MJ / m 2 That is the case.

[0090] As is clear from the above examples, the laminate satisfying the requirements of the present invention, by comprising a coating layer containing a calcium derivative, was able to exhibit excellent flame retardancy without ignition in a cone calorimeter test, even when the polyurethane foam layer was formed from a urethane resin composition substantially free of fillers. In contrast, in the comparative example, the above-mentioned coating layer was not formed on the polyurethane foam layer, and therefore excellent flame retardancy could not be achieved.

Claims

1. A laminate comprising a polyurethane foam layer and a coating material layer laminated on the surface of the polyurethane foam layer, The polyurethane foam layer is a spray foam formed from a urethane resin composition containing a polyol, polyisocyanate, hydrofluoroolefin, catalyst, and phosphate ester-based flame retardant. The catalyst comprises a quaternary ammonium salt and a bismuth salt. The isocyanate index of the urethane resin composition is 300 or more. The aforementioned urethane resin composition is substantially free of fillers, A laminate comprising the aforementioned coating layer containing a calcium derivative.

2. The laminate according to claim 1, wherein the quaternary ammonium salt comprises tetramethylammonium salt.

3. The laminate according to claim 1 or 2, wherein the catalyst comprises an imidazole derivative.

4. The laminate according to claim 1 or 2, wherein the coating layer comprises at least one selected from the group consisting of aluminum hydroxide, mica, glass fiber, silica, sodium oxide, and aluminum oxide.

5. The laminate according to claim 4, wherein the coating layer comprises at least one of aluminum hydroxide and glass fibers.

6. The laminate according to claim 5, wherein the coating layer contains glass fibers.

7. The laminate according to claim 1 or 2, wherein the calcium derivative comprises at least one selected from the group consisting of calcium sulfate, calcium carbonate, and tricalcium silicate.

8. The laminate according to claim 1 or 2, wherein the content of the filler in the urethane resin composition is 3 parts by mass or less per 100 parts by mass of the polyol.

9. The laminate according to claim 1 or 2, wherein a primer layer is provided between the polyurethane foam layer and the coating material layer, or the coating material layer contains an adhesion promoter.

10. The laminate according to claim 9, wherein at least one of the primer layer and the adhesion promoter includes at least one selected from the group consisting of vinyl copolymer resin, acrylic copolymer resin, methacrylic copolymer resin, epoxy resin, rubber resin, silicone resin, and ethylene-vinyl acetate copolymer resin.

11. A urethane resin composition for providing the laminate according to claim 1 or 2, The urethane resin composition comprises a polyol, a polyisocyanate, a hydrofluoroolefin, a catalyst, and a phosphate ester-based flame retardant. The catalyst comprises a quaternary ammonium salt and a bismuth salt. The isocyanate index of the urethane resin composition is 300 or more. The urethane resin composition is a urethane resin composition that is substantially free of fillers.

Images