Polyurethane foam

Abstract

To provide a technology capable of ensuring flame retardancy either through reduced use or complete elimination of halogen-based and antimony-based flame retardants.SOLUTION: Provided is a polyurethane foam derived from a composition comprising a polyol, an isocyanate, and a compound represented by the following formula (1). (In the formula, R1 and R2 are each independently a hydrocarbon group which may have a substituent other than halogen; n is each independently an integer from 0 to 4; and R3 is a hydrocarbon group which may have a substituent other than halogen and which does not have a hydroxyl group).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present disclosure relates to polyurethane foams. [Background technology]

[0002] Patent Document 1 discloses a flame-retardant polyurethane composition containing chlorinated polyvinyl chloride and antimony oxide. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 03-007716 Summary of the Invention [Problem to be solved by the invention]

[0004] The use of halogenated and antimony-based flame retardants places a heavy burden on the environment and the human body. Therefore, as halogenated and antimony-based flame retardants are either subject to regulation or are likely to be subject to regulation in the future, alternative substances are being sought.

[0005] The present disclosure aims to provide a technology that can reduce the amount of halogen-based flame retardants and antimony-based flame retardants used, or ensure the flame retardancy of polyurethane foam without using any halogen-based flame retardants or antimony-based flame retardants. [Means for solving the problem]

[0006] [1] A polyurethane foam obtained from a composition containing a polyol, an isocyanate, and a compound represented by the following chemical formula (1): [ka] (In the formula, R 1 and R 2each independently represents a hydrocarbon group which may have a substituent other than halogen; each n independently represents an integer of 0 to 4; R 3 is a hydrocarbon group which may have a substituent other than a halogen and does not have a hydroxyl group. Effect of the Invention

[0007] According to the present disclosure, it is possible to provide a technique that can reduce the amount of halogen-based flame retardants and antimony-based flame retardants used, or ensure flame retardancy without using any halogen-based flame retardants or antimony-based flame retardants. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a diagram for explaining the mechanism when a cyclic phosphorus compound and cellulose acetate are used in combination. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Here, a preferred example of the present disclosure is given. [2] The polyurethane foam described in [1], wherein the composition further contains cellulose acetate.

[0010] [3] The polyurethane foam according to [1] or [2], wherein the composition further contains phenoxyphosphazene.

[0011] [4] A polyurethane foam according to any one of [1] to [3], having a compressive residual strain of less than 20% as measured in accordance with JIS K6400-4:2004 A method.

[0012] The present disclosure will be described in detail below. In this specification, when a numerical range is described using "-", the lower limit and the upper limit are included unless otherwise specified. For example, the description "10-20" includes both the lower limit "10" and the upper limit "20". In other words, "10-20" has the same meaning as "10 or more and 20 or less". In this specification, the upper limit and the lower limit of each numerical range can be arbitrarily combined.

[0013] 1.Polyurethane foam The polyurethane foam is obtained from a composition containing a polyol, an isocyanate, and a compound represented by the following chemical formula (1) (hereinafter also simply referred to as a cyclic phosphorus compound). [ka] (In the formula, R 1 and R 2 each independently represents a hydrocarbon group which may have a substituent other than halogen, and each n independently represents an integer of 0 to 4, R 3 is a hydrocarbon group which may have a substituent other than a halogen and does not have a hydroxyl group.

[0014] (1) Polyol The polyol is not particularly limited, and various polyols may be used alone or in combination of two or more kinds. Examples of the polyol include polyether polyol, polyester polyol, polyether ester polyol, polycarbonate diol, and polyol having a carbon-carbon bond main chain. Examples of polyether polyols include polyoxypropylene-polyoxyethylene polyols, polymer polyols, and polyoxytetramethylene glycol. Examples of the polyester polyol include aliphatic or aromatic polycondensation polyester polyols and polycaprolactone polyols. Examples of polyols having a carbon-carbon bond-based main chain include polyolefin polyols such as polybutadiene polyol and isoprene polyol, and acrylic polyol.

[0015] (1.1) Polyether polyols Examples of polyether polyols include polyether polyols obtained by adding one or more of ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, epichlorohydrin, styrene oxide, etc. to one or more of the following initiators (compounds), or polytetramethylene ether glycol.

[0016] (1.1.1) Initiator (1.1.1.1) Polyhydric alcohols and alkylene oxide adducts of polyhydric alcohols Examples of polyhydric alcohols: [Difunctional alcohol] Ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, trimethylene glycol [Trifunctional alcohol] Glycerin, trimethylolpropane [Tetrafunctional alcohol] Pentaerythritol [Hexafunctional alcohol] Sorbitol [Octanoic alcohol] Sucrose (1.1.1.2) Alkylene oxide adducts of polyhydric phenols Examples of alkylene oxide adducts of polyhydric phenols: alkylene oxide adducts of bisphenol A (1.1.1.3) Polyhydroxy compounds Examples of polyhydroxy compounds are phosphoric acid, benzene phosphoric acid, polyphosphoric acid (e.g. tripolyphosphoric acid and tetrapolyphosphoric acid), etc. (1.1.1.4) Phenol-aniline-formaldehyde ternary condensation products (1.1.1.5) Aniline-formaldehyde condensation products (1.1.1.6) Polyamines Examples of polyamines: ethylenediamine, diethylenetriamine, triethylenetetramine, methylenebisorthochloroaniline, 4,4- and 2,4'-diphenylmethanediamine, 2,4-tolylenediamine, 2,6-tolylenediamine, etc. (1.1.1.7) Alkanolamines Examples of alkanolamines: triethanolamine, diethanolamine, etc.

[0017] (1.1.2) Polymer polyol The polymer polyol is a polyol obtained by graft-polymerizing the above-mentioned polyether polyol with an ethylenically unsaturated compound such as acrylonitrile, styrene, or alkyl methacrylate.

[0018] (1.1.3) Ethylene oxide unit content The content of the ethylene oxide unit in the polyether polyol is not particularly limited. The content of the ethylene oxide unit is preferably more than 0 mol% and not more than 50 mol%, more preferably more than 3 mol% and not more than 20 mol%, and even more preferably more than 5 mol% and not more than 10 mol%, when the total amount of the alkylene oxide unit is 100 mass%.

[0019] (1.2) Polyester polyol The polyester polyols are polyester polyols obtained by condensation of one or more compounds having at least two hydroxyl groups with one or more compounds having at least two carboxyl groups, or ring-opening polymers of cyclic esters such as caprolactone and methylvalerolactone.

[0020] (1.2.1) Examples of compounds having at least two hydroxy groups Ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, tetramethylene glycol, neopentyl glycol, methylpentanediol, butylethylpropanediol, hexamethylene glycol, decamethylene glycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol

[0021] (1.2.2) Examples of compounds having at least two carboxyl groups Oxalic acid, malonic acid, maleic acid, succinic acid, tartaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, hemimellitic acid

[0022] (1.3) Polycarbonate polyol Examples of polycarbonate polyols include those obtained by transesterification of a low molecular weight polyol such as butanediol or hexanediol with a low molecular weight carbonate such as propylene carbonate or diethyl carbonate.

[0023] (1.4) Polyolefin polyols Examples of polyolefin polyols include polybutadiene polyols, polyisoprene polyols, hydrogenated polybutadiene polyols, and hydrogenated polyisoprene polyols.

[0024] (1.5) Plant-derived polyols The polyol may include a plant-derived polyol in addition to the above polyol. Examples of the plant-derived polyol include castor oil-based polyol, soybean oil-based polyol, palm oil-based polyol, palm kernel oil-based polyol, coconut oil-based polyol, cashew oil-based polyol, olive oil-based polyol, cottonseed oil-based polyol, safflower oil-based polyol, sesame oil-based polyol, sunflower oil-based polyol, and linseed oil-based polyol. The plant-derived polyols usually have 2-3 functional hydroxyl groups in one molecule. Examples of castor oil-based polyols include castor oil, a reaction product of castor oil with a polyol, an esterification reaction product of castor oil fatty acid with a polyol, etc. Examples of polyols to be reacted with castor oil or castor oil fatty acid include divalent polyols such as ethylene glycol, diethylene glycol, and propylene glycol, and trivalent or higher polyols such as glycerin, trimethylolpropane, hexanetriol, and sorbitol. The soybean oil-based polyol may be a polyol derived from soybean oil, such as a reaction product of soybean oil and a polyol, or an esterification reaction product of soybean oil fatty acid and a polyol. The polyol to be reacted with soybean oil or soybean oil fatty acid may be the same as that of castor oil. The same applies to palm oil-based polyol, cashew oil-based polyol, and the like. The various polyols exemplified as plant-derived polyols may be used alone or in combination of two or more kinds.

[0025] (1.6) Weight average molecular weight, hydroxyl value, and functionality The weight average molecular weight, hydroxyl value, and number of functional groups of the polyol are not particularly limited. The weight average molecular weight of the polyol is preferably from 500 to 10000, more preferably from 1000 to 6000, and further preferably from 1500 to 4000. The weight average molecular weight of the polyol can be measured by gel permeation chromatography (GPC). The hydroxyl value of the polyol is preferably from 40 mgKOH / g to 300 mgKOH / g, more preferably from 45 mgKOH / g to 150 mgKOH / g, and further preferably from 50 mgKOH / g to 80 mgKOH / g. The functionality of the polyol is preferably at least 2.0, more preferably at least 2.1, and even more preferably at least 2.2. The functionality of the polyol is, for example, at most 4.0.

[0026] (2) Cyclic phosphorus compounds The composition (hereinafter also referred to as a composition for polyurethane foam) contains a compound represented by the following chemical formula (1) from the viewpoint of improving flame retardancy while ensuring various physical properties of polyurethane foam. [ka] In the formula, R 1 and R 2 R is a hydrocarbon group which may have a substituent other than halogen. 1 The number of carbon atoms in R is, for example, 1 to 3. 2 The number of carbon atoms is, for example, 1 to 3. Each n is independently an integer of 0 to 4, preferably 0 to 2, more preferably 0 to 1, and even more preferably 0. R 3 R is a hydrocarbon group which may have a substituent other than halogen and does not have a hydroxyl group. 3 The number of carbon atoms in R is, for example, 1 to 8. 3 is preferably a phenyl group, a tolyl group, or a xylyl group, and more preferably a phenyl group.

[0027] The present inventors have conducted extensive research into flame retardants that can improve the flame retardancy of polyurethane foam while maintaining various physical properties. In general, flame retardants that have a low melting point (e.g., less than 200°C) and active hydrogen are thought to inhibit reactions such as urethanization reactions, thereby deteriorating the physical properties of polyurethane foam. The present inventors have newly discovered that cyclic phosphorus compounds that have a hydroxyl group and are water-soluble, even if they have a melting point of 200°C or higher, tend to degrade the physical properties of polyurethane foam. Based on these discoveries, the present disclosure has been developed using the compound of the above chemical formula (1).

[0028] The cyclic phosphorus compound is preferably a compound represented by the following chemical formula (2). The compound represented by the following chemical formula (2) is also called 9,10-dihydro-10-benzyl-9-oxa-10-phosphaphenanthrene-10-oxide (CAS No. 113504-81-7). An example of a commercially available product is BCA manufactured by Sanko Co., Ltd. [ka]

[0029] The properties of the cyclic phosphorus compound are not particularly limited. The cyclic phosphorus compound is preferably a powder. The melting point of the cyclic phosphorus compound is preferably higher than 100°C. The decomposition temperature of the cyclic phosphorus compound is preferably 250°C or higher, more preferably 300°C or higher. The decomposition temperature of the cyclic phosphorus compound is, for example, 500°C or lower. From the viewpoint of improving flame retardancy, the phosphorus content of the cyclic phosphorus compound may be, for example, 9% by mass or more and 11% by mass. The phosphorus content (mass%) can be calculated as the mass of phosphorus atoms contained relative to the mass of one molecule of the cyclic phosphorus compound, that is, (mass of phosphorus atoms / mass of one molecule of the cyclic phosphorus compound)×100.

[0030] The amount of the cyclic phosphorus compound is not particularly limited. The amount of the cyclic phosphorus compound is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, even more preferably 8 parts by mass or more, and particularly preferably 12 parts by mass or more, relative to 100 parts by mass of polyol, from the viewpoint of ensuring sufficient flame retardancy. On the other hand, the amount of the cyclic phosphorus compound is preferably 30 parts by mass or less, more preferably 28 parts by mass or less, even more preferably 25 parts by mass or less, and particularly preferably 22 parts by mass or less, from the viewpoint of maintaining various physical properties of polyurethane foam and from the viewpoint of production cost. From these viewpoints, the amount of the cyclic phosphorus compound is preferably 3 parts by mass or more and 30 parts by mass or less, more preferably 5 parts by mass or more and 28 parts by mass or less, even more preferably 8 parts by mass or more and 25 parts by mass or less, and particularly preferably 12 parts by mass or more and 22 parts by mass or less, relative to 100 parts by mass of polyol.

[0031] (3) Cellulose acetate The polyurethane foam composition preferably further contains cellulose acetate. Cellulose acetate can be obtained by esterifying cellulose, which is a natural polymer. Cellulose is a polymer with anhydroglucose as a repeating unit, and has three hydroxyl groups per repeating unit. Depending on the degree of esterification (substitution degree), cellulose acetate resins with different properties can be obtained. The substitution degree is expressed as an index called the acetylation degree. The acetylation degree of cellulose in which all three hydroxyl groups are acetylated, i.e., triacetyl cellulose, is 62.5%. The acetylation degree of the cellulose acetate used in this embodiment is preferably 40%-62%, more preferably 43%-60%. The average polymerization degree is not particularly limited, and is preferably about 100-400, for example.

[0032] The cellulose acetate is preferably in the form of a powder, and examples of the shape of the powder include a spherical shape, an ellipsoid shape, a polygonal shape (such as a polygonal pyramid shape, a cuboid shape, a rectangular parallelepiped shape, etc.), a plate shape or a flake shape (a scale shape), a rod shape, and an amorphous shape. From the viewpoint of ensuring various physical properties of the polyurethane foam, the cellulose acetate is preferably spherical and has an average particle size of 2 μm to 40 μm. The average particle size of the spherical microparticles can be measured, for example, by a Coulter Counter manufactured by Coulter Electronics. The particle size of the cellulose acetate is not particularly limited, and may be, for example, a particle size of more than 500 μm. "Particle size of more than 500 μm" refers to, for example, the particle size of cellulose acetate classified using a metal mesh sieve with a mesh size of 500 μm as specified in JIS Z8801-1 (2006). The upper limit of the particle size of the cellulose acetate is not particularly limited, and may be, for example, a particle size of 1500 μm or less.

[0033] The amount of cellulose acetate is not particularly limited. The amount of cellulose acetate is preferably 0.5 parts by mass or more, more preferably 0.8 parts by mass or more, even more preferably 1.2 parts by mass or more, and particularly preferably 1.5 parts by mass or more, relative to 100 parts by mass of polyol, from the viewpoint of ensuring sufficient flame retardancy. On the other hand, the amount of cellulose acetate is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, even more preferably 6 parts by mass or less, and particularly preferably 4 parts by mass or less, from the viewpoint of maintaining various physical properties of polyurethane foam and from the viewpoint of production cost. From these viewpoints, the amount of cellulose acetate is preferably 0.5 parts by mass or more and 10 parts by mass or less, more preferably 0.8 parts by mass or more and 8 parts by mass or less, even more preferably 1.2 parts by mass or more and 6 parts by mass or less, and particularly preferably 1.5 parts by mass or more and 4 parts by mass or less, relative to 100 parts by mass of polyol.

[0034] Although the details of the mechanism by which the flame retardancy can be improved when a cyclic phosphorus compound is used in combination with cellulose acetate compared to when a cyclic phosphorus compound is used alone are not clear, it is presumed as follows. However, the present disclosure is not limited in any way by this presumed mechanism. The presumed mechanism will be described with reference to FIG. 1. FIG. 1 is a schematic diagram of a polyurethane foam 10 containing a cyclic phosphorus compound and cellulose acetate. 10 O5) nis a conceptual representation of only the cellulose component of cellulose acetate. When cyclic phosphorus compounds are thermally decomposed, phosphoric acid or polyphosphoric acid (polymers of phosphorus) is formed, which undergoes repeated dehydration and condensation, forming a highly viscous liquid. 10 O5) n can be dehydrated and carbonized as follows: (C6H 10 O5) n → 6nC + 5nH2O It is presumed that this causes a molten glassy phosphate layer 11 and a dense carbonized layer 12 to form on the surface of the polyurethane foam 10, blocking oxygen and heat.

[0035] (4) Phenoxyphosphazene The polyurethane foam composition preferably further contains phenoxyphosphazene. Phenoxyphosphazene is a type of phosphazene compound to which CAS No. 28212-48-8 is assigned. Phenoxyphosphazene is also called Poly(bis(phenoxy)phosphazene) or Hexaphenoxycyclotriphosphazene Oligomer. Phenoxyphosphazene is a halogen-free flame retardant. Phenoxyphosphazene does not contain an active hydrogen group, and is therefore considered to be less likely to cause reaction inhibition such as urethanization reaction.

[0036] The properties of phenoxyphosphazene are not particularly limited. Phenoxyphosphazene is preferably a powder. The melting point of phenoxyphosphazene is usually higher than 100°C. The decomposition temperature of phenoxyphosphazene is usually 300°C or higher and 500°C or lower. From the viewpoint of ensuring sufficient flame retardancy, the phosphorus content in phenoxyphosphazene is preferably higher than the phosphorus content of the above cyclic phosphorus compound.

[0037] The amount of phenoxyphosphazene is not particularly limited. The amount of phenoxyphosphazene is preferably 1 part by mass or more, more preferably 4 parts by mass or more, even more preferably 6 parts by mass or more, and particularly preferably 8 parts by mass or more, relative to 100 parts by mass of polyol, from the viewpoint of ensuring sufficient flame retardancy. On the other hand, the amount of phenoxyphosphazene is preferably 20 parts by mass or less, more preferably 18 parts by mass or less, even more preferably 16 parts by mass or less, and particularly preferably 14 parts by mass or less, from the viewpoint of maintaining various physical properties of polyurethane foam and from the viewpoint of production cost. From these viewpoints, the amount of phenoxyphosphazene is preferably 1 part by mass or more and 20 parts by mass or less, more preferably 4 parts by mass or more and 18 parts by mass or less, even more preferably 6 parts by mass or more and 16 parts by mass or less, and particularly preferably 8 parts by mass or more and 14 parts by mass or less, relative to 100 parts by mass of polyol.

[0038] (5) Catalyst The polyurethane foam composition may contain a catalyst. The catalyst is not particularly limited. Various catalysts may be used alone or in combination of two or more kinds. As the catalyst, an amine catalyst or a quaternary ammonium salt catalyst can be used. Specific examples of these catalysts are shown below. Tertiary amine catalysts such as N,N-dimethylaminohexanol, N,N,N'-trimethyl-N'-aminopropyl-bis(aminoethyl)ether, triethylenediamine, triethylamine, tripropylamine, triisopropanolamine, tributylamine, trioctylamine, hexadecyldimethylamine, N-methylmorpholine, N-ethylmorpholine, N-octadecylmorpholine, monoethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N,N-dimethylethanolamine, N,N-dimethylaminoethoxyethoxyethanol, and N,N-dimethylaminoethoxyethanol; formate and other salts of triethylenediamine; oxyalkylene adducts of amino groups of primary and secondary amines; azacyclic compounds such as N,N'-dialkylpiperazines; and amine catalysts having an amino group as a functional group such as N,N,N",N"-tetramethyldiethylenetriamine. In addition, quaternary ammonium salt catalysts such as tetraalkylammonium halides such as tetramethylammonium chloride, tetraalkylammonium hydroxides such as tetramethylammonium hydroxide salts, and tetraalkylammonium organic acid salts such as tetramethylammonium 2-ethylhexanoate, 2-hydroxypropyltrimethylammonium formate, and 2-hydroxypropyltrimethylammonium 2-ethylhexanoate can also be used. The amount of one or more catalysts selected from the group consisting of amine catalysts and quaternary ammonium salt catalysts in the polyurethane foam composition is not particularly limited. The amount of these catalysts is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and even more preferably 0.07 parts by mass or more, relative to 100 parts by mass of polyol, from the viewpoint of sufficiently promoting the polyurethane production reaction. On the other hand, from the viewpoint of maintaining various physical properties of polyurethane foam and from the viewpoint of production cost, it is preferably 1 part by mass or less, more preferably 0.8 parts by mass or less, and even more preferably 0.5 parts by mass or less. From these viewpoints, the amount of one or more catalysts selected from the group consisting of amine catalysts and quaternary ammonium salt catalysts is preferably 0.01 parts by mass or more and 1 part by mass or less, more preferably 0.05 parts by mass or more and 0.8 parts by mass or less, and even more preferably 0.07 parts by mass or more and 0.5 parts by mass or less, relative to 100 parts by mass of polyol.

[0039] As the catalyst, a metal catalyst (organometallic catalyst) can be used. As the metal catalyst, any conventionally known metal catalyst can be used without any particular limitation. Examples of the metal catalyst that can be used include metal salts of Sn (tin), Pb (lead), Bi (bismuth), Ni (nickel), Co (cobalt), Fe (iron), Zr (zirconium), Cu (copper), Zn (zinc), etc., and organic acid metal salts. More specifically, the following metal catalysts can be used. Sn catalyst: stannous octoate (stannous 2-ethylhexanoate, stannous dioctoate), stannous acetate, stannous octanoate, stannous dioleate, stannous neodecanoate, stannous dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dichloride, dioctyltin dilaurate, dibutyltin dimaleate, dioctyltin diacetate, etc. Pb catalyst: lead octoate, lead naphthenate, etc. Bi catalyst: bismuth octoate, bismuth naphthenate, bismuth neodecanoate, bismuth rosinate, etc. Fe catalyst: iron acetylacetonate, etc. Zr catalyst: zirconium acetylacetonate, etc. Ni catalyst: Nickel acetylacetonate, nickel octylate, nickel naphthenate, etc. Co catalyst: cobalt acetylacetonate, cobalt octylate, cobalt naphthenate, etc.

[0040] The amount of the metal catalyst in the polyurethane foam composition is not particularly limited. The amount of the metal catalyst is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and even more preferably 0.1 parts by mass or more, relative to 100 parts by mass of polyol, from the viewpoint of sufficiently promoting the polyurethane production reaction. On the other hand, from the viewpoint of suppressing volatile organic compounds (such as 2-ethylhexanoic acid) derived from the metal catalyst, it is preferably 1.0 parts by mass or less, more preferably 0.6 parts by mass or less, and even more preferably 0.4 parts by mass or less. From these viewpoints, the amount of the metal catalyst is preferably 0.01 parts by mass or more and 1.0 parts by mass or less, more preferably 0.05 parts by mass or more and 0.6 parts by mass or less, and even more preferably 0.1 parts by mass or more and 0.4 parts by mass or less, relative to 100 parts by mass of polyol.

[0041] (6) Foam stabilizer The polyurethane foam composition may contain a foam stabilizer. The foam stabilizer is not particularly limited. Specific examples of the foam stabilizer include silicone compounds such as organopolysiloxane, organopolysiloxane-polyoxyalkylene copolymer, polyalkenylsiloxane having a polyoxyalkylene side chain, silicone-grease copolymer, etc., anionic surfactants such as sodium dodecylbenzenesulfonate and sodium lauryl sulfate, polyether siloxane, phenolic compounds, etc. These foam stabilizers may be used alone or in combination of two or more kinds. The amount of the foam stabilizer is not particularly limited, but is preferably 0.03 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the polyol.

[0042] (7) Foaming agent The polyurethane foam composition may contain a blowing agent. The blowing agent is not particularly limited. As the blowing agent, water, pentane, cyclopentane, hexane, cyclohexane, dichloromethane, carbon dioxide gas, etc. are preferably used. When the blowing agent is water, the amount of water added is determined within a range that allows the polyurethane foam to have a desired density and a good foaming state, and is usually preferably 1 part by mass or more and 10 parts by mass or less per 100 parts by mass of polyol.

[0043] (8) Isocyanate The isocyanate is not particularly limited. At least one selected from the group consisting of aromatic isocyanates, alicyclic isocyanates, and aliphatic isocyanates is preferably used as the isocyanate. At least one aliphatic isocyanate and at least one aromatic isocyanate may be used in combination. The isocyanate may be either a bifunctional isocyanate having two isocyanate groups in one molecule, or a trifunctional or higher isocyanate having three or more isocyanate groups in one molecule, and may be used alone or in combination. For example, bifunctional isocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, xylylene diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate, and 3,3'-dimethoxy-4,4'-biphenylene diisocyanate. Examples of the isocyanate include aromatic isocyanates such as ylene diisocyanate, alicyclic isocyanates such as cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, and methylcyclohexane diisocyanate, and aliphatic isocyanates such as butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, and lysine isocyanate. Examples of tri- or higher functional isocyanates include 1-methylbenzene-2,4,6-triisocyanate, 1,3,5-trimethylbenzene-2,4,6-triisocyanate, biphenyl-2,4,4'-triisocyanate, diphenylmethane-2,4,4'-triisocyanate, methyldiphenylmethane-4,6,4'-triisocyanate, 4,4'-dimethyldiphenylmethane-2,2',5,5'tetraisocyanate, triphenylmethane-4,4',4"-triisocyanate, and polymeric MDI. In addition, urethane prepolymers, carbodiimide-modified isocyanates, isocyanurate-modified isocyanates, and biuret-modified isocyanates can also be used.

[0044] The mixing ratio of isocyanate and polyol is not particularly limited. The isocyanate index is preferably 80 or more and 120 or less. The isocyanate index (INDEX) is a value obtained by multiplying the number of moles of isocyanate groups per mole of active hydrogen groups contained in the composition by 100, and is calculated by [(isocyanate equivalent in the composition / active hydrogen equivalent in the composition)×100].

[0045] (9) Other additives The polyurethane foam composition may contain other additives, such as crosslinking agents, plasticizers, fillers, antioxidants, UV absorbers, defoamers, compatibilizers, colorants, stabilizers, antibacterial agents, antifungal agents, deodorants, deodorants, fragrances, and flavorings. Examples of crosslinking agents include short-chain diol crosslinking agents such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, glycerin, and trimethylolpropane. Examples of coloring agents include pigments, dyes, and coloring agents.

[0046] (10) Physical properties of polyurethane foam The physical properties of the polyurethane foam can be appropriately set depending on the application, etc. The polyurethane foam is preferably a flexible polyurethane foam. The polyurethane foam preferably has the following physical properties: (10.1) Apparent density Apparent density (JISK7222:2005) is 8kg / m 3 -120kg / m 3 is preferred, and 10 kg / m 3 -80kg / m 3 More preferably, 15 kg / m 3 -45kg / m 3 is more preferred. (10.2) Hardness The hardness (JIS K6400-2 D method: 2012) is preferably 10N to 600N, more preferably 50N to 300N, and further preferably 80N to 150N. If it is in this range, it is highly flexible and is preferable as a flexible polyurethane foam. (10.3) Resilience The rebound resilience (JIS K6400-3:2011) is preferably 1% to 80%, more preferably 5% to 70%, and even more preferably 15% to 60%. (10.4) Compressive Residual Set The compressive set (JIS K6400-4 4.5.2A method: 2004) is preferably less than 20%, more preferably less than 10%, and even more preferably less than 5%. The lower limit of the compressive set is not particularly limited, and is, for example, 0% or more. (10.5) Airflow The ventilation rate (JIS K6400-7 Method A: 2012) is preferably 25 L / min or more, more preferably 40 L / min or more, and even more preferably 60 L / min or more. The ventilation rate is usually 300 L / min or less.

[0047] 2. Polyurethane foam manufacturing Polyurethane foam can be produced by a known foaming method in which a polyurethane foam composition is stirred and mixed to react a polyol with an isocyanate. The foaming method includes slab foaming and mold foaming, and either molding method may be used. Slab foaming is a method in which a mixed polyurethane foam composition is discharged onto a belt conveyer and foamed at atmospheric pressure and room temperature. On the other hand, mold foaming is a method in which a mixed polyurethane foam composition is filled into a mold (forming die) and foamed in the mold.

[0048] 3. Uses of polyurethane foam The polyurethane foam of the present embodiment is used, for example, as a flame-retardant polyurethane foam. The use of the polyurethane foam is not particularly limited. The polyurethane foam of the present embodiment can reduce the amount of halogen-based flame retardants and antimony-based flame retardants used, or can ensure flame retardancy without using halogen-based flame retardants and antimony-based flame retardants, by using a cyclic phosphorus compound. The polyurethane foam of the present embodiment is useful for various applications as a polyurethane foam having flame retardancy with little load on the environment and human body. In addition, the polyurethane foam of the present embodiment uses a cyclic phosphorus compound, It is possible to ensure various physical properties such as compressive residual strain, making it suitable for a variety of applications.

[0049] The polyurethane foam of the present embodiment is suitable for use as a vehicle interior member since it has flame retardancy. The vehicle interior member is not particularly limited. Examples of the vehicle interior member include members used for vehicle seats and members used for vehicle interior materials. EXAMPLES

[0050] 1. Polyurethane foam production The polyurethane foams of the Reference Example, the Examples, and the Comparative Examples were produced by slab foaming, using compositions prepared according to the ratios shown in Tables 1-4. The Reference Example is a comparative example in which the composition does not contain the compound of the above chemical formula (1) (flame retardant 1). The details of each raw material are as follows: Polyol: Polyether polyol, functionality 3, weight average molecular weight 3000, hydroxyl value 56.1 mgKOH / g, ethylene oxide content 8% by mass Foaming agent: Water Amine catalyst 1: N,N-dimethylaminohexanol Amine catalyst 2: Aliphatic amine catalyst, manufactured by EVONIC, product name NE-300 Foam stabilizer: Silicone foam stabilizer, Product name: SZ-1136, manufactured by Dow Corning Toray Isocyanate: Tolylene diisocyanate (mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate) Tin catalyst: Tin(II) octoate Flame retardant 1: 9,10-dihydro-10-benzyl-9-oxa-10-phosphaphenanthrene-10-oxide (CAS No. 113504-81-7), Sanko Co., Ltd., product name BCA, corresponds to the compound of the above chemical formula (2). Flame retardant 2: 6H-dibenzo[c,e][1,2]oxaphosphorine 6-oxide (CAS No. 35948-25-5), Pharmicell, product name DPP Flame retardant 3: 3-[hydroxy(phenyl)phosphoryl]propanoic acid (CAS No. 14657-64-8), Pharmicell, product name Phoretar 101 Flame retardant 4: Poly(bis(phenoxy)phosphazene) (CAS No. 28212-48-8), Pharmicell, product name Phoretar 201 Flame retardant 5: 10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (CAS No. 99208-50-1), Sanko Co., Ltd., product name HCA-HQ Flame retardant 6: Halogen-containing condensed phosphate ester, Daihachi Chemical Industry Co., Ltd., product name CR-504L Cellulose acetate 1: flake, particle size over 500μm, reagent Cellulose acetate 2: spherical particles, average particle size 7μm, manufactured by Daicel Corporation, product name BELLOCEA

[0051] Specifically, the polyurethane foam was produced according to the following procedure. The raw materials other than the isocyanate were weighed and mixed in a cup container to prepare a mixed solution. An isocyanate was added to the mixed solution, and the mixture was stirred to prepare a composition.

[0052] [Table 1]

[0053] [Table 2]

[0054] [Table 3]

[0055] [Table 4]

[0056] The properties of flame retardant 1-8 and cellulose acetate 1,2 are summarized in Table 5. In addition, for flame retardant 1-8 and cellulose acetate 1,2, the results of the following experimental examples regarding "reactivity," "physical properties," and "flame retardancy" are also summarized in Table 5. Flame Retardant 1: Example 1 Flame retardant 2: Comparative example 2 Flame retardant 3: Comparative example 3 Flame retardant 4: Comparative example 5 Flame retardant 5: Comparative example 8 Flame retardants 6: Reference examples Cellulose acetate 1: Comparative Example 11 Cellulose acetate 2: Comparative Example 14 [Table 5]

[0057] 2. Evaluation method (1) Apparent density (density) The apparent density was measured according to JIS K7222:2005. (2) Hardness (25% ILD hardness) The hardness was measured according to JIS K6400-2 Method D:2012. In addition, for Comparative Examples 10, 11, and 13 to 15, the 25% CLD hardness was measured according to ASTM D 3574-11. The 25% CLD hardness is shown with "( )" next to the numerical value. (3) Resilience The impact resilience was measured according to JIS K6400-3:2011. (4) Compressive residual strain The compression set was measured according to JIS K6400-4 4.5.2A method:2004, 50% compression, 70°C, and 22 hours. (5) Airflow rate The air permeability was measured according to JIS K6400-7 Method A.

[0058] (6) Combustion test Combustion test specimens (N=5) were cut out from the polyurethane foams of the Reference Examples, Comparative Examples, and Examples. A combustion test was performed on each combustion test specimen in accordance with the flame retardancy standard UL94HF-1 of the Underwriters Laboratory in the United States. In the UL94HF-1 test, the combustion test specimen was placed on a wire mesh and exposed to a gas burner so that the flame reached the entire edge (2 inches wide) of the specimen.

[0059] The items in Table 1-4 are as follows: Burning distance: The burning distance (mm) from the end of the test piece was measured, and the average value of five burning test pieces was calculated. Afterflame time: The burning time (seconds) from 60 seconds after flame application until the flame went out was measured, and the average value of five burning test pieces was calculated. Number of drops: The drops were counted and the average value of five combustion test pieces was calculated. Ignition: The number of ignited test pieces was counted. In Table 1-4, it is expressed as the number of ignited test pieces / total number of test pieces.

[0060] (7) Reactivity The reactivity of the polyurethane foam was evaluated. If the reactivity was good, it was marked as "good", and if it was poor, it was marked as "poor" and the possible reasons for the poor reactivity were noted. (8) Form appearance The appearance of the polyurethane foam was evaluated. When the appearance of the polyurethane foam was good, it was rated as "good", and when it was poor, it was rated as "poor" and the details were recorded. (9) Physical properties The compressive residual strain, which is an index of physical properties, was evaluated according to the following criteria. A: Less than 5% B: Less than 10% C: Less than 20% D: 20% or more (10) Flammability The average burning distance (N=5) was evaluated according to the following criteria. The "-" in the flammability evaluation means that the evaluation was not performed. A: Less than 60mm B: Less than 80mm C: Less than 100mm D:100mm or more

[0061] 3.Results The evaluation results are shown in Table 1-4. The composition of Example 1-12 contains a polyol, an isocyanate, and the compound of the above chemical formula (1). The polyurethane foam of Example 1-12 was evaluated for physical properties as "A", "B", or "C". The polyurethane foam of Example 1-12 was evaluated for flammability as "A", "B", or "C". It was found that Example 1-12 has both physical properties and flame retardancy and is suitable for practical use.

[0062] In contrast, the composition of Comparative Example 1-15 does not contain the compound of the above chemical formula (1). The polyurethane foam of Comparative Example 1-15 was rated "D" in at least one of the physical properties and flammability. It was found that Comparative Example 1-15 is not suitable for practical use.

[0063] This will be examined in more detail below. Comparative Example 1 is an example (blank) that does not contain a flame retardant. The burning distance of Comparative Example 1 was 125 mm, and the flame retardancy was evaluated as "D."

[0064] The reference example is an example in which 20 parts by mass of a halogen-based flame retardant was added. The burning distance of the reference example was 45 mm. The reference example was rated "A" for both physical properties and flammability. However, the use of a halogen-based flame retardant in the reference example raises concerns about the burden on the environment and human body.

[0065] Comparative Examples 2 and 3 are examples in which 5 parts by mass of flame retardant 2 (DPP) and flame retardant 3 (Phoretar 101) were added. Foaming inhibition occurred in Comparative Examples 2 and 3. It is considered possible that the active hydrogen contained in flame retardant 2 (DPP) and flame retardant 3 (Phoretar 101) inhibited the reaction.

[0066] In Example 1-3, 10 parts by mass, 20 parts by mass, and 25 parts by mass of flame retardant 1 (BCA) were added. The burning distances of Examples 1-3 were 75 mm, 55 mm, and 45 mm, respectively. It was suggested that the flame retardancy could be improved by adding flame retardant 1 (BCA).

[0067] Comparative Example 4-6 is an example in which 5 parts by mass, 10 parts by mass, and 20 parts by mass of flame retardant 5 (Phoretar 201) were added alone. The burning distances of Comparative Example 4-6 were 125 mm, 125 mm, and 115 mm, respectively. Flame retardant 5 (Phoretar 201) alone could not sufficiently improve the flame retardancy.

[0068] In Example 4-6, 3 parts by mass, 5 parts by mass, and 10 parts by mass of flame retardant 5 (Phoretar 201) were added in addition to 10 parts by mass of flame retardant 1 (BCA). The burning distances of Examples 4-6 were 75 mm, 72 mm, and 59 mm, respectively. It was suggested that the combined use of flame retardant 1 (BCA) and flame retardant 5 (Phoretar 201) could improve the flame retardancy more than that of flame retardant 1 (BCA) alone.

[0069] Comparative Example 7-9 is an example in which 5 parts by mass, 10 parts by mass, and 20 parts by mass of flame retardant 5 (HCA-HQ) were added. The burning distances of Comparative Example 7-9 were 123 mm, 56 mm, and 40 mm, respectively. It was suggested that flame retardancy could be improved by adding flame retardant 5 (HCA-HQ). However, the physical properties of Comparative Example 7-9 were all evaluated as "D." Flame retardant 5 (HCA-HQ) has a hydroxyl group (active hydrogen) and is water-soluble, which may have deteriorated the physical properties.

[0070] Comparative Examples 10-12 are examples in which cellulose acetate (particle size over 500 μm) was added in amounts of 5 parts by mass, 10 parts by mass, and 20 parts by mass, respectively. Comparative Examples 13-15 are examples in which cellulose acetate (average particle size 7 μm) was added in amounts of 5 parts by mass, 10 parts by mass, and 20 parts by mass, respectively. The burning distances of Comparative Examples 10-15 were all 125 mm, suggesting that there was no flame retardant effect.

[0071] In Examples 7-9, 10 parts by mass of flame retardant 1 (BCA) was added in combination with 1 part by mass, 3 parts by mass, and 5 parts by mass of cellulose acetate (particle size over 500 μm). The burning distances of Examples 7-9 were 56 mm, 64 mm, and 51 mm. Examples 10-12 are examples in which cellulose acetate (average particle size 7 μm) was added in amounts of 1 part by mass, 3 parts by mass, and 5 parts by mass in addition to 10 parts by mass of flame retardant 1 (BCA). The burning distances of Examples 10-12 were 71 mm, 57 mm, and 24 mm. It was suggested that the combined use of flame retardant 1 (BCA) and cellulose acetate could improve the flame retardancy more than that of flame retardant 1 (BCA) alone.

[0072] According to the above examples, it was possible to ensure flame retardancy without using halogen-based flame retardants and antimony-based flame retardants. It was also confirmed that the compound of the above chemical formula (1) can be used as a substitute for halogen-based flame retardants.

[0073] The present disclosure is not limited to the embodiments described above in detail, and various modifications and variations are possible within the scope of the present disclosure.

Claims

1. A polyurethane foam obtained from a composition containing a polyol, an isocyanate, and a compound represented by the following chemical formula (1): 【Chemistry 1】 (In the formula, R １ and R ２ each independently represents a hydrocarbon group which may have a substituent other than halogen; each n independently represents an integer of 0 to 4; R ３ is a hydrocarbon group which may have a substituent other than halogen and does not have a hydroxyl group.

2. The polyurethane foam of claim 1 , wherein the composition further comprises cellulose acetate.

3. The polyurethane foam of claim 1 or claim 2, wherein the composition further comprises a phenoxyphosphazene.

4. The polyurethane foam according to claim 1 or 2, having a compression set measured in accordance with JIS K6400-4:2004 Method A of less than 20%.

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