Soft polyurethane foam and sheet

Abstract

To provide a soft polyurethane foam having flame retardancy.SOLUTION: A soft polyurethane foam is derived from a composition for producing a polyurethane foam that includes a polyol composition A comprising an unsaturated carboxylic acid partial ester of a polyol and an aromatic-containing polyester polyol, and an isocyanate.SELECTED DRAWING: None

Description

Technical Field

[0001] The present disclosure relates to flexible polyurethane foams and sheets.

Background Art

[0002] Patent Document 1 describes a flexible or semi-rigid flame-retardant polyurethane foam having excellent charring performance and containing a specific phosphorus compound.

[0003] Patent Document 2 describes a method for producing a flame-retardant flexible polyurethane foam. In this production method, as the polyol, a polymer-dispersed polyol (I) having a specific composition in which aldehyde condensation resin fine particles or polymer fine particles of an aldehyde condensation resin fine particle and a polymerizable unsaturated group-containing monomer are dispersed is used.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] Techniques for imparting flame retardancy to flexible polyurethane foams have been studied. However, the conventional techniques need to be improved in the following points. For example, the conventionally used halogen-containing phosphorus-based flame retardants are required to reduce the addition amount or not to use them in order to reduce the environmental load. In addition, it is also required to further improve the flame retardant performance of flexible polyurethane foams and satisfy the flame retardant standards for various applications. In addition, it is also required to ensure various physical properties while ensuring the flame retardancy of flexible polyurethane foams. The present disclosure has been made to solve at least one of the above-described problems, and an object thereof is to provide a flexible polyurethane foam having flame retardancy. The present disclosure can be realized in the following forms.

Means for Solving the Problems

[0006] A polyol composition A containing an unsaturated carboxylic acid partial ester of a polyol and an aromatic-containing polyester polyol, an isocyanate, A flexible polyurethane foam obtained from a composition for producing a polyurethane foam containing the same.

Effects of the Invention

[0007] According to the present disclosure, a flexible polyurethane foam having flame retardancy can be provided.

Modes for Carrying Out the Invention

[0008] Here, desirable examples of the present disclosure are shown. 〔1〕 A flexible polyurethane foam obtained from a composition for producing a polyurethane foam containing an unsaturated carboxylic acid partial ester of a polyol and an aromatic-containing polyester polyol, an isocyanate, and the same. 〔2〕 The flexible polyurethane foam according to 〔1〕, which is a flame-retardant polyurethane foam. 〔3〕 A sheet comprising the flexible polyurethane foam according to 〔1〕 or 〔2〕.

[0009] Hereinafter, the present disclosure will be described in detail. In this specification, for a description using "~" for a numerical range, unless otherwise specified, it is assumed to include the lower limit value and the upper limit value. For example, in the description "10~20", both the lower limit value "10" and the upper limit value "20" are included. That is, "10~20" has the same meaning as "10 or more and 20 or less". Also, in this specification, the upper limit value and the lower limit value of each numerical range can be arbitrarily combined.

[0010] 1. Flexible polyurethane foam The flexible polyurethane foam is obtained from a composition for producing a polyurethane foam, which includes a polyol composition A containing an unsaturated carboxylic acid partial ester of a polyol and an aromatic-containing polyester polyol, and an isocyanate.

[0011] "Polyol composition A" includes an unsaturated carboxylic acid partial ester of a polyol and an aromatic-containing polyester polyol. Among the polyols contained in the composition for producing a polyurethane foam, the polyol not contained in "polyol composition A" is also referred to as "polyol composition B". "Polyol composition B" includes one or more polyols. When referring to the total polyols contained in the composition for producing a polyurethane foam, it means the sum of "polyol composition A" and "polyol composition B".

[0012] (1) Polyol composition A The hydroxyl value, functionality, and weight average molecular weight of polyol composition A are not particularly limited. The hydroxyl value of polyol composition A is preferably 100 mgKOH / g or more and 400 mgKOH / g or less, more preferably 120 mgKOH / g or more and 300 mgKOH / g or less, and still more preferably 150 mgKOH / g or more and 250 mgKOH / g or less. The functionality number of the polyol composition A is preferably 4 or less, more preferably 3 or less, and still more preferably 2.5 or less. The functionality number of the polyol composition A is usually greater than 1 and 1.5 or more. Note that the functionality number of the polyol composition A can be calculated from the functionality numbers of the respective components contained in the entire polyol composition A and the molar fractions of the respective components. The weight average molecular weight of the polyol composition A is preferably 100 or more and 2000 or less, more preferably 200 or more and 1500 or less, and still more preferably 400 or more and 1000 or less. In the present disclosure, the weight average molecular weight of the polyol can be measured, for example, by the gel permeation chromatography (GPC) method.

[0013] In the polyol composition A, the mass ratio of the unsaturated carboxylic acid partial ester of the polyol to the aromatic-containing polyester polyol is not particularly limited. The mass ratio of the unsaturated carboxylic acid partial ester of the polyol:aromatic-containing polyester polyol is preferably, for example, 0.1:99.9 to 99.8:0.2, more preferably 5:95 to 90:10, and still more preferably 5:95 to 80:20.

[0014] When the total amount of the polyols contained in the composition for producing a polyurethane foam is 100 parts by mass, the content of the polyol composition A is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, and still more preferably 8 parts by mass or more from the viewpoint of flame resistance (flame retardancy). From the viewpoint of the physical properties of the flexible polyurethane foam, the content of the polyol composition A is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and still more preferably 15 parts by mass or less. From these viewpoints, the content of the polyol composition A is preferably 3 parts by mass or more and 30 parts by mass or less, more preferably 5 parts by mass or more and 20 parts by mass or less, and still more preferably 8 parts by mass or more and 15 parts by mass or less. Hereinafter, preferred examples of the components of the polyol composition A will be described.

[0015] (1.1) Unsaturated carboxylic acid partial ester of polyol The above polyol is preferably at least one selected from, for example, polyhydric alcohols, polyhydric phenols, alkylene oxide (hereinafter abbreviated as AO) adducts of polyhydric alcohols or polyhydric phenols, AO adducts of amines, and polyester polyols derived from polyhydric alcohols and polycarboxylic acids or lactones. The unsaturated carboxylic acid ester is preferably, for example, a (meth)acrylic acid ester. In this specification, “(meth)acrylic acid” means acrylic acid and / or methacrylic acid, and “(meth)acrylic acid ester” means acrylic acid ester and / or methacrylic acid ester. The partial ester means that a part of the hydroxyl groups of the polyol is esterified with an unsaturated carboxylic acid.

[0016] The polyhydric alcohol used for producing the unsaturated carboxylic acid partial ester of the polyol is preferably at least one selected from the group consisting of, for example, a polyhydric alcohol having 3 to 18 carbon atoms (hereinafter abbreviated as C), a 3- to 5-valent polyhydric alcohol, a divalent alcohol having 2 to 18 carbon atoms, and a 6- to 10-valent or higher polyhydric alcohol having 5 to 18 carbon atoms. Specific examples of the 3- to 5-valent polyhydric alcohol having 3 to 18 carbon atoms (preferably 3 to 12 carbon atoms) include alkane polyols and intramolecular or intermolecular dehydrates thereof, such as pentaerythritol, glycerin, trimethylolpropane, sorbitan, diglycerin; saccharides and derivatives thereof, such as α-methylglucoside, xylitol, glucose, fructose; and the like. Specific examples of the divalent alcohol having 2 to 18 carbon atoms (preferably 2 to 12 carbon atoms) include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4- and 1,3-butanediol, 1,6-hexanediol, and neopentyl glycol. Specific examples of the 6- to 10-valent or higher polyhydric alcohol having 5 to 18 carbon atoms (preferably 5 to 12 carbon atoms) include 6- to 10-valent alkane polyols and intramolecular or intermolecular dehydrates of polyhydric alkane polyols, such as dipentaerythritol; saccharides and derivatives thereof, such as sorbitol, mannitol, sucrose; and the like.

[0017] The unsaturated carboxylic acid partial ester of the polyol may be only one kind or two or more kinds. The unsaturated carboxylic acid partial ester of the polyol preferably contains at least a compound obtained by reacting dipentaerythritol and acrylic acid.

[0018] The unsaturated carboxylic acid partial ester of the polyol has at least one active hydrogen-containing group, preferably 1 to 8, more preferably 1 to 5, particularly preferably 1 to 3, and most preferably 1 to 2. When the number of active hydrogen-containing groups is 1 to 8, the curability during the molding of the polyurethane resin is good. In addition, when the composition of the reaction mixture etc. is not single, the number-average number is used for the number of vinyl polymerizable functional groups and the number of active hydrogen-containing groups of the unsaturated carboxylic acid partial ester of the polyol.

[0019] The active hydrogen value of the unsaturated carboxylic acid partial ester of the polyol is 10 to 1300, and from the viewpoint of mechanical properties such as compressive hardness, 20 to 1000 is preferable, more preferably 30 to 600, and particularly preferably 40 to 500. Here, the active hydrogen value means "56100 / molecular weight per active hydrogen", and when the group having an active hydrogen is a hydroxyl group, it corresponds to the hydroxyl value. The method for measuring the active hydrogen value may be a known method as long as it can measure the value defined above, and is not particularly limited, but in the case of the hydroxyl value, for example, the method described in JIS K1557-1 can be mentioned.

[0020] From the viewpoint of flame resistance (flame retardancy), the vinyl polymerizable functional group concentration (mmol / g) of the unsaturated carboxylic acid partial ester of the polyol is preferably 1.0 to 13.0, and more preferably 2.0 to 10.1.

[0021] (1.2) Aromatic-containing polyester polyol An aromatic-containing polyester polyol is preferably, for example, an active hydrogen-containing compound (a polyester compound) obtained by a condensation reaction of an active hydrogen-containing compound and a polycarboxylic acid (an aliphatic polycarboxylic acid or an aromatic polycarboxylic acid). In the condensation reaction, one kind of the active hydrogen-containing compound and the polycarboxylic acid may be used, or two or more kinds may be used in combination. In addition, since the aromatic-containing polyester polyol has an aromatic ring, it is necessary to use a compound having an aromatic ring in at least one of the polycarboxylic acid and the active hydrogen-containing compound used in the condensation reaction.

[0022] An aliphatic polycarboxylic acid means a compound satisfying the following [1] and [2]. [1] It has two or more carboxyl groups per molecule. [2] The carboxyl group is not directly bonded to the aromatic ring.

[0023] Examples of the aliphatic polycarboxylic acid include succinic acid, adipic acid, sebacic acid, maleic acid, and fumaric acid.

[0024] An aromatic polycarboxylic acid means a compound satisfying the following [1] to [3]. [1] It has one or more aromatic rings per molecule. [2] It has two or more carboxyl groups per molecule. [3] The carboxyl group is directly bonded to the aromatic ring.

[0025] The aromatic polycarboxylic acid is preferably one or more selected from aromatic polycarboxylic acids having 8 to 18 carbon atoms such as phthalic acid, isophthalic acid, terephthalic acid, 2,2'-bibenzyl dicarboxylic acid, trimellitic acid, hemimellitic acid, trimesic acid, pyromellitic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-2,3,6-tricarboxylic acid, diphenic acid, 2,3-anthracene dicarboxylic acid, 2,3,6-anthracene tricarboxylic acid, and pyrene dicarboxylic acid.

[0026] In addition, when carrying out the condensation reaction between a polycarboxylic acid and an active hydrogen-containing compound, an anhydride or a lower alkyl ester of the polycarboxylic acid can also be used.

[0027] The active hydrogen-containing compound used for the production of the polyester compound is preferably at least one selected from, for example, polyhydric alcohols and polyhydric phenols. The polyhydric alcohol is preferably at least one selected from, for example, divalent alcohols having 2 to 20 carbon atoms, trivalent alcohols having 3 to 20 carbon atoms, and tetra- to octavalent alcohols having 5 to 20 carbon atoms. Specific examples of the divalent alcohol having 2 to 20 carbon atoms are aliphatic diols (such as diethylene glycol, ethylene glycol, propylene glycol, 1,3- and 1,4-butanediol, 1,6-hexanediol, and neopentyl glycol) and alicyclic diols (such as cyclohexanediol and cyclohexanedimethanol). Specific examples of the trivalent alcohol having 3 to 20 carbon atoms are aliphatic triols (such as triethylene glycol, glycerin, and trimethylolpropane). Specific examples of the tetra- to octavalent polyhydric alcohol having 5 to 20 carbon atoms are aliphatic polyols (such as pentaerythritol, sorbitol, mannitol, sorbitan, diglycerin, and dipentaerythritol) and saccharides (such as sucrose, glucose, mannose, fructose, methyl glucoside, and derivatives thereof).

[0028] The aromatic-containing polyester polyol may be only one kind or two or more kinds. The aromatic-containing polyester polyol preferably contains at least a compound obtained by adding diethylene glycol and / or triethylene glycol to terephthalic acid and / or phthalic acid.

[0029] The aromatic ring concentration of the aromatic-containing polyester polyol is preferably 1.2 to 16.0 (mmol / g), more preferably 1.5 to 13.0 (mmol / g), and still more preferably 2.0 to 11.0 (mmol / g) from the viewpoints of various physical properties and flame resistance (flame retardancy) of the flexible polyurethane foam.

[0030] (2) Polyol Composition B The polyol contained in the polyol composition B is not particularly limited as long as it is not an unsaturated carboxylic acid partial ester of the polyol and is not an aromatic-containing polyester polyol.

[0031] From the viewpoint of the various physical properties of the flexible polyurethane foam, the polyol composition B preferably contains a polyether polyol. The polyether polyol is, for example, at least one selected from the group consisting of polyoxypropylene polyol, polyoxyethylene polyol, polyoxypropylene polyoxyethylene polyol, polymer polyol, and polyoxytetramethylene glycol. The polyether polyol may be only one kind or two or more kinds.

[0032] The hydroxyl value, functionality, and weight average molecular weight of the polyether polyol are not particularly limited. The hydroxyl value of the polyether polyol is preferably 20 mgKOH / g or more and 120 mgKOH / g or less, more preferably 25 mgKOH / g or more and 100 mgKOH / g or less, and still more preferably 30 mgKOH / g or more and 80 mgKOH / g or less. The functionality of the polyether polyol is preferably 4 or less, more preferably 3 or less. The functionality of the polyether polyol is usually 2 or more. The weight average molecular weight of the polyether polyol is preferably 800 or more and 12000 or less, more preferably 1000 or more and 10000 or less, still more preferably 2000 or more and 8000 or less, and particularly preferably 3000 or more and 7500 or less. In addition, when the polyol composition B contains two or more kinds of polyether polyols, at least one kind of polyether polyol may be within the above range.

[0033] When the total content of the polyether polyol is 100 parts by mass based on the total polyol contained in the composition for producing polyurethane foam, from the perspective of the various physical properties of the flexible polyurethane foam, it is preferably 50 parts by mass or more, more preferably 60 parts by mass or more, and still more preferably 70 parts by mass or more. From the perspective of ensuring the amount of polyol composition A and improving the flame resistance (fire retardancy), the total content of the above polyether polyol is preferably 97 parts by mass or less, more preferably 95 parts by mass or less, and still more preferably 90 parts by mass or less. From these perspectives, the total content of the above polyether polyol is preferably 50 parts by mass or more and 97 parts by mass or less, more preferably 60 parts by mass or more and 95 parts by mass or less, and still more preferably 70 parts by mass or more and 90 parts by mass or less.

[0034] From the perspective of reducing the compression set of the flexible polyurethane foam, polyol composition B preferably contains a polyether polyol having a weight average molecular weight of 6000 or more. The upper limit value of the weight average molecular weight of this polyether polyol is not particularly limited and is usually 20000 or less. When the total content of the polyether polyol having a weight average molecular weight of 6000 or more is 100 parts by mass based on the total polyol contained in the composition for producing polyurethane foam, from the perspective of reducing the compression set, it is preferably 20 parts by mass or more, more preferably 25 parts by mass or more, and still more preferably 35 parts by mass or more. From the perspective of ensuring the amount of polyol composition A and considering the productivity of the flexible polyurethane foam, the content of the above polyether polyol having a weight average molecular weight of 6000 or more is preferably 80 parts by mass or less, more preferably 70 parts by mass or less, and still more preferably 60 parts by mass or less. From these perspectives, the content of the above polyether polyol having a weight average molecular weight of 6000 or more is preferably 20 parts by mass or more and 80 parts by mass or less, more preferably 25 parts by mass or more and 70 parts by mass or less, and still more preferably 35 parts by mass or more and 60 parts by mass or less.

[0035] From the perspective of improving the air permeability of flexible polyurethane foam, the polyol composition B preferably contains a polyether polyol containing ethylene oxide units (hereinafter also referred to as an EO-containing polyether polyol) as the polyether polyol. When the total amount of alkylene oxide units is 100% by mass, the content of ethylene oxide units in the EO-containing polyether polyol is preferably 50% by mass or more, more preferably 60% by mass or more, and still more preferably 65% by mass or more. The above content of ethylene oxide units is 100% by mass or less, and from the perspective of the physical properties of flexible polyurethane foam, it may be 90% by mass or less, or 85% by mass or less.

[0036] When the total amount of polyols contained in the composition for producing polyurethane foam is 100 parts by mass, from the perspective of improving air permeability, the content of the EO-containing polyether polyol is preferably more than 0.5 part by mass, more preferably 1.0 part by mass or more, and still more preferably 2.0 parts by mass or more. From the perspective of the physical properties of flexible polyurethane foam, the content of the above EO-containing polyether polyol is preferably 6.5 parts by mass or less, more preferably 5.5 parts by mass or less, and still more preferably 4.5 parts by mass or less. From these perspectives, the content of the above EO-containing polyether polyol is preferably more than 0.5 part by mass and 6.5 parts by mass or less, more preferably 1.0 part by mass or more and 5.5 parts by mass or less, and still more preferably 2.0 parts by mass or more and 4.5 parts by mass or less.

[0037] (3) Catalyst The composition for producing polyurethane foam may contain a catalyst. The catalyst is not particularly limited. Various catalysts may be used alone or in combination of two or more. As the catalyst, for example, one or more selected from amine catalysts and quaternary ammonium salt catalysts can be used. Specific examples of these catalysts are shown. 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, N,N-dimethylaminoethoxyethanol, etc., formates and other salts of triethylenediamine, oxyalkylene adducts of amino groups of primary and secondary amines, azacyclic compounds such as N,N'-dialkylpiperazines, amine catalysts having an amino group as a functional group such as N,N,N",N"-tetramethyldiethylenetriamine, etc. can be employed. Also, quaternary ammonium salt catalysts such as tetraalkylammonium halides such as tetramethylammonium chloride, tetraalkylammonium hydroxides such as tetramethylammonium hydroxide salt, tetramethylammonium 2-ethylhexanoate, 2-hydroxypropyltrimethylammonium formate, 2-hydroxypropyltrimethylammonium 2-ethylhexanoate, etc. can be employed. The total blending amount of one or more catalysts selected from the group consisting of amine catalysts and quaternary ammonium salt catalysts is not particularly limited. From the viewpoint of sufficiently promoting the production reaction of polyurethane, the total blending amount of these catalysts is preferably 0.01 part by mass or more, more preferably 0.1 part by mass or more, and still more preferably 0.3 part by mass or more with respect to 100 parts by mass of the polyol. On the other hand, from the viewpoints of maintaining the physical properties of the flexible polyurethane foam and the manufacturing cost, it is preferably 3 parts by mass or less, more preferably 2 parts by mass or less, and still more preferably 1.5 parts by mass or less. From these viewpoints, the total blending amount of these catalysts is preferably 0.01 part by mass or more and 3 parts by mass or less, more preferably 0.1 part by mass or more and 2 parts by mass or less, and still more preferably 0.3 part by mass or more and 1.5 parts by mass or less with respect to 100 parts by mass of the polyol.

[0038] As a catalyst, a metal catalyst (organometallic catalyst) can be used. As the metal catalyst, a conventionally known metal catalyst can be adopted without particular limitation. As the metal catalyst, for example, metal salts such as Sn (tin), Pb (lead), Bi (bismuth), Ni (nickel), Co (cobalt), Fe (iron), Zr (zirconium), Cu (copper), Zn (zinc), etc., and metal organic acid salts can be used. More specifically, the following metal catalysts can be used. Sn catalyst: Tin (II) octylate (tin 2-ethylhexanoate, stannous dioctoate), tin (II) acetate, tin (II) octanoate, stannous dioleate, tin (II) neodecanoate, stannous dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dichloride, dioctyltin dilaurate, dibutyltin dimaleate, dioctyltin diacetate, etc. Pb catalyst: Lead octylate, lead naphthenate, etc. Bi catalyst: Bismuth octylate, 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.

[0039] (4) Foam stabilizer The composition for producing polyurethane foam may contain a foam stabilizer. The foam stabilizer is not particularly limited. The foam stabilizer is specifically a silicone compound such as organopolysiloxane, organopolysiloxane - polyoxyalkylene copolymer, polyalkenylsiloxane having a polyoxyalkylene side chain, silicone - grease copolymer, anionic surfactant such as sodium dodecylbenzenesulfonate, sodium lauryl sulfate, polyethersiloxane, phenolic compound, etc. These foam stabilizers may be used alone or in combination of two or more. The compounding amount of the foam stabilizer is not particularly limited. The compounding amount of the foam stabilizer 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.

[0040] (5) Flame retardant The composition for producing polyurethane foam may contain a flame retardant. The flame retardant is not particularly limited. The flame retardant is, for example, one or more selected from phosphate - based flame retardants, phosphate - containing flame retardants, organic flame retardants, and inorganic flame retardants, etc. The phosphate - based flame retardant may be a halogen - containing phosphate - based flame retardant or a non - halogen phosphate - based flame retardant. The organic flame retardant is, for example, melamine resin, urea resin, polyvinyl chloride, etc. The organic flame retardant may be compounded into the composition for producing polyurethane foam in a form contained in the polymer polyol.

[0041] The compounding amount of the flame retardant is not particularly limited. When the flame retardancy of the composition for producing polyurethane foam is sufficiently ensured by the polyol composition A, it is preferably not to contain a flame retardant other than the polyol composition A. Even when containing a flame retardant, from the viewpoints of reducing the usage amount of the flame retardant and the manufacturing cost, the compounding amount of the flame retardant is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and still more preferably 10 parts by mass or less with respect to 100 parts by mass of the polyol. From these viewpoints, the compounding amount of the flame retardant is preferably 0 parts by mass or more and 20 parts by mass or less, more preferably 15 parts by mass or less, and still more preferably 10 parts by mass or less with respect to 100 parts by mass of the polyol.

[0042] (6) Blowing agent The composition for producing polyurethane foam may contain a blowing agent. The blowing agent is not particularly limited. The blowing agent is preferably at least one selected from, for example, water, pentane, cyclopentane, hexane, cyclohexane, dichloromethane, and carbon dioxide gas. When the blowing agent is water, the addition amount is determined within a range where the desired density and good foaming state can be obtained in the polyurethane foam, and usually 1 part by mass or more and 10 parts by mass or less is preferable with respect to 100 parts by mass of the polyol.

[0043] (7) 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 employed. One or more aliphatic isocyanates and one or more aromatic isocyanates may be used in combination. Further, the isocyanate may be either a bifunctional isocyanate having two isocyanate groups in one molecule or a trifunctional or higher-functional isocyanate having three or more isocyanate groups in one molecule, and may be used alone or in combination of a plurality. For example, the bifunctional isocyanate is, for example, an aromatic isocyanate such as 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, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, an alicyclic isocyanate such as cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, methylcyclohexane diisocyanate, or an aliphatic isocyanate such as butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, lysine isocyanate, and is one or more selected therefrom. Furthermore, the polyfunctional isocyanate is, for example, at least one selected from 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, polymeric MDI, and the like. In addition, the isocyanate may be at least one selected from polyol-modified isocyanates, carbodiimide-modified isocyanates, isocyanurate-modified isocyanates, and biuret-modified isocyanates.

[0044] From the perspective of the various physical properties of the flexible polyurethane foam, the isocyanate preferably contains at least a polyol-modified isocyanate, and more preferably contains a polyol-modified isocyanate and tolylene diisocyanate. The polyol-modified isocyanate is a compound obtained by reacting an isocyanate with a polyol. The polyol-modified isocyanate is preferably a polyol-modified product of an aromatic isocyanate, and more preferably a polyol-modified product of diphenylmethane diisocyanate. The polyol-modified product of diphenylmethane diisocyanate is also called an MDI prepolymer. Commercially available products of the polyol-modified isocyanate are, for example, Coronate 1050, Coronate 1057 (both manufactured by Tosoh Corporation), and the like. When the total amount of the isocyanate is 100 parts by mass, the content of the polyol-modified isocyanate is preferably 5 parts by mass or more and 40 parts by mass or less, more preferably 10 parts by mass or more and 30 parts by mass or less, and still more preferably 15 parts by mass or more and 25 parts by mass or less.

[0045] The mixing ratio of the isocyanate and the 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 by 100 the number of moles of isocyanate groups per mole of active hydrogen groups contained in the composition, and is calculated by [(isocyanate equivalent in the composition / equivalent of active hydrogen in the composition) × 100].

[0046] (8) Other additives The composition for producing a polyurethane foam may appropriately contain other additives, such as a crosslinking agent, a plasticizer, a filler, an antioxidant, an ultraviolet absorber, a defoaming agent, a compatibilizer, a colorant, a stabilizer, an antibacterial agent, a fungicide, a deodorant, an odor eliminator, a fragrance, a perfume, etc. The crosslinking agent is preferably at least one selected from, for example, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4 - butanediol, glycerin, and trimethylolpropane. The colorant is, for example, a pigment, a dye, a coloring agent, etc.

[0047] (9) Physical properties of the flexible polyurethane foam The physical properties of the flexible polyurethane foam can be appropriately set according to the use, etc. The flexible polyurethane foam preferably has the following physical properties. The following physical properties are measured on a sample obtained from the core of the flexible polyurethane foam.

[0048] (9.1) Apparent density The apparent density (JIS K7222:2005) is 20 kg / m 3 or more and 80 kg / m 3 or less, preferably 25 kg / m 3 or more and 65 kg / m 3 or less, more preferably 30 kg / m 3 or more and 50 kg / m 3 or less, even more preferably. (9.2) Hardness Hardness (JIS K6400-2:2012 6.7 D method) is preferably 20 N or more and 200 N or less, more preferably 30 N or more and 150 N or less, and even more preferably 40 N or more and 100 N or less. Within this range, it is rich in flexibility and preferable as a soft polyurethane foam. (9.3) Resilience Resilience (JIS K6400-3:2011) is preferably 20% or more and 80% or less, more preferably 25% or more and 70% or less, and even more preferably 30% or more and 65% or less.

[0049] (9.4) Tensile strength, elongation, tear strength Tensile strength (JIS K6400-5:2012 3) is preferably 40 kPa or more, more preferably 50 kPa or more, and even more preferably 60 kPa or more. The upper limit value of the tensile strength is not particularly limited, for example, it is 120 kPa or less. Elongation (JIS K6400-5:2012 3) is preferably 50% or more and 500% or less, more preferably 80% or more and 200% or less, and even more preferably 90% or more and 150% or less. Tear strength (JIS K6400-5:2012, No. 4 type) is preferably 1 N / cm or more, more preferably 2 N / cm or more, and even more preferably 3 N / cm or more. The upper limit value of the tear strength is not particularly limited, for example, it is 10 N / cm or less.

[0050] (9.5) Air permeability The air permeability of the soft polyurethane foam (JIS K6400-7:2012 B method) is preferably 40 cm 3 / cm 2 / sec or more and 150 cm 3 / cm 2 / sec or less, more preferably 50 cm 3 / cm 2 / sec or more and 100 cm 3 / cm 2 / sec or less, and even more preferably 60 cm 3 / cm 2 / sec or more and 80 cm 3 / cm 2 / sec or less.

[0051] (9.6) Compressive residual strain The compressive residual strain (JIS K6400-4:2004 4.5.2 Method A) is preferably 20% or less, more preferably 15% or less, and still more preferably 10% or less. The lower limit value of the compressive residual strain is not particularly limited and is usually greater than 0%. The compressive residual strain was calculated as the amount of deformation (%) with respect to the thickness before compression after the sample was compressed to 50% of its thickness, left in a drying oven at 70°C for 22 hours, and then the compression was released and the thickness was measured in accordance with Method A of JIS K6400-4.

[0052] (9.7) Combustion test based on the railway vehicle A-A standard The flexible polyurethane foam preferably passes the combustion test based on the railway vehicle A-A standard. When passing the combustion test standard, the deformation (mm) after alcohol combustion is more preferably 150 mm or less, and still more preferably 100 mm or less. In the combustion test based on the railway vehicle A-A standard, the ignition / flaming / smoke / fire intensity during alcohol combustion, the afterflame / soot / carbonization (mm) / deformation (mm) after alcohol combustion, and the alcohol combustion time (s) are evaluated.

[0053] (9.8) Fire resistance test (FAR 25.853 test for aircraft interiors) The flexible polyurethane foam preferably passes the FAR 25.853 test for aircraft interiors. In the FAR 25.853 test for aircraft interiors, the fire extinguishing time (s) / combustion length (inch) / drop fire extinguishing time (s) in the vertical test are evaluated.

[0054] 2. Manufacture of flexible polyurethane foam Flexible polyurethane foam can be produced by a known foaming method in which a composition for producing polyurethane foam is stirred and mixed to react a polyol and an isocyanate. The foaming methods include slab foaming and mold foaming, and any of the molding methods may be used. Slab foaming is a method in which the mixed composition for producing polyurethane foam is discharged onto a belt conveyor and foamed at normal temperature under atmospheric pressure. On the other hand, mold foaming is a method in which the mixed composition for producing polyurethane foam is filled into a mold (molding die) and foamed within the mold.

[0055] 3. Uses, effects and functions of flexible polyurethane foam Flexible polyurethane foam is used in various applications. One of them is the seats of railway vehicles and airplanes. Severe flame retardancy standards are specified for each of them, and it is necessary to install urethane foam classified as flame retardant. However, since urethane is generally a combustible substance, various techniques for imparting flame retardancy have been studied conventionally. For example, as in the reference example described later, by using a melamine-based flame retardant, flexible polyurethane foam that meets the flame retardancy standards for railway vehicles and airplanes has been developed. Currently, a technique to replace the melamine-based flame retardant is required. When a flame retardant such as a halogen-containing phosphate ester-based flame retardant is used instead of the melamine-based flame retardant, in order to meet the severe flame retardancy standards it is necessary to add a large amount of flame retardant, and problems remain in terms of the physical properties and cost of the flexible polyurethane foam.

[0056] The polyol composition A has conventionally been used as a raw material for rigid urethane foam and has not been considered for application to flexible polyurethane foam. The inventors have conducted intensive studies and have developed a flexible polyurethane foam using the polyol composition A. The flexible polyurethane foam using the polyol composition A can have sufficient flame retardancy, for example, without using other flame retardants. Furthermore, the flexible polyurethane foam using the polyol composition A can have various physical properties required for flexible polyurethane foam.

[0057] The flexible polyurethane foam of this embodiment is suitable for various applications. The applications of the flexible polyurethane foam are not particularly limited. For example, since the flexible polyurethane foam of this embodiment has flexibility and flame retardancy, it is suitable as a member used for a seat. Further, since the flexible polyurethane foam of this embodiment has sufficient flame retardancy, it is also suitable as an interior member for a vehicle. The interior member for a vehicle is not particularly limited. The interior member for a vehicle is, for example, a member used for a vehicle seat, a member used for an interior material for a vehicle, or the like. In this embodiment, since it can have high flame retardancy that meets the flame retardancy standard of the combustion test based on the A-A standard of a railway vehicle, it is suitable as a member (seat) used for a railway vehicle. Further, in this embodiment, since it can have high flame retardancy that passes the aircraft FAR 25.853 test, it is also suitable as a member (seat) used for an aircraft. In the present disclosure, when referring to a "flame retardant polyurethane foam", it is only necessary to satisfy the flame retardancy standard according to its application or the like. The flame retardancy standard is not limited to the standard defined in the combustion test based on the A-A standard of a railway vehicle or the aircraft FAR 25.853 test, and may be, for example, the standard defined in the flame retardancy standard UL94HF-1 of Underwriters Laboratory of the United States.

[0058] Furthermore, by using the polyol composition A, the flexible polyurethane foam of this embodiment can reduce the amount of a flame retardant other than the polyol composition A or can have sufficient flame retardancy without using a flame retardant other than the polyol composition A. Therefore, the flexible polyurethane foam of this embodiment is useful as a flexible polyurethane foam with less environmental impact. Also, the flexible polyurethane foam of this embodiment can suppress the roughening of cells, an unintentional increase in air permeability, etc. caused by the addition of a flame retardant.

Examples

[0059] 1. Manufacture of flexible polyurethane foam Compositions were prepared by blending at the ratios shown in Table 1, and flexible polyurethane foams of the reference examples, examples, and comparative examples were produced by the following method. The reference examples are comparative examples in which the composition does not contain polyol composition A. Polyols 1 to 4 are polyols contained in polyol composition B. First, the raw material mixture was poured into an open-top, unsealed foaming box, and the raw material mixture was allowed to freely foam in the foaming box. Further, the foaming box containing the foam was placed in an oven set at 70°C to accelerate the curing of the foam. For all reference examples, examples, and comparative examples, a 270 mm square cardboard foaming box was used.

[0060] The details of each raw material are as follows. · Polyol 1: Polyether polyol, functionality 3, weight average molecular weight 7000, hydroxyl value 24 mg KOH / g, EP902, manufactured by Mitsui Chemicals, Inc. · Polyol 2: Polyether polyol, functionality 3, weight average molecular weight 5000, hydroxyl value 35 mg KOH / g, F3135, manufactured by Wanhua Chemical Group Co., Ltd. · Polyol 3: Polyether polyol, functionality 2, weight average molecular weight 1000, hydroxyl value 112 mg KOH / g, D1000, manufactured by Mitsui Chemicals, Inc. · Polyol 4: Polyether polyol (polyoxypropylene polyoxyethylene polyol, EO-containing polyether polyol), functionality 3, weight average molecular weight 3300, hydroxyl value 52 mg KOH / g, ethylene oxide content 70 mass%, manufactured by Mitsui Chemicals, Inc. · Polyol 5: Polymer polyol (melamine-based polymer polyol with polyether polyol as the base polyol), functionality 3, weight average molecular weight 5000, hydroxyl value 25 mg KOH / g, M950, manufactured by Asahi Glass Co., Ltd. · Polyol composition A: Non-fluoropolyol, functionality 2, weight average molecular weight 600, hydroxyl value 200 mg KOH / g, manufactured by Sanyo Chemical Industries, Ltd. Note that the non-phosphorus flame retardant includes a compound obtained by reacting dipentaerythritol with acrylic acid as an unsaturated carboxylic acid partial ester of a polyol, and the aromatic-containing polyester polyol includes a compound obtained by adding diethylene glycol and / or triethylene glycol to terephthalic acid and / or phthalic acid. · Catalyst 1: Diethanolamine · Catalyst 2: Amine catalyst, 33LSI, manufactured by Evonik · Catalyst 3: Amine catalyst, NIAX A-1, manufactured by Momentive · Foam stabilizer: Dimethyl siloxane copolymer · Flame retardant 1: Halogen-containing phosphate flame retardant, TMCPP, manufactured by Daihachi Chemical Industry Co., Ltd. · Flame retardant 2: Halogen-containing condensed phosphate flame retardant, CR504L, manufactured by Daihachi Chemical Industry Co., Ltd. · Blowing agent: Water

[0061] As the isocyanate, a mixture obtained by mixing the following Isocyanate 1 and Isocyanate 2 at a ratio of 80:20 (mass ratio) was used. The NCO% of the mixture was 40.31%. · Isocyanate 1: A mixture of 80% by mass of tolylene diisocyanate (TDI) and 20% by mass of diphenylmethane diisocyanate (MDI). The tolylene diisocyanate (TDI) is a mixture of 2,4-tolylene diisocyanate:2,6-tolylene diisocyanate = 80:20, NCO% 44.64%, Cosmonate TM20, manufactured by Mitsui Chemicals, Inc. · Isocyanate 2: Polyol-modified MDI, NCO% 23.00%, Coronate 1050, manufactured by Tosoh Corporation

[0062] The flexible polyurethane foam was specifically manufactured by the following procedure. The raw materials other than isocyanate were weighed into a cup container, stirred, and made into a mixed solution (Solution A). Isocyanate (Solution B) was added to the mixed solution (Solution A) and stirred to obtain a composition.

[0063]

Table 1

[0064] 2. Evaluation method Evaluation samples were prepared as follows. Regarding the flexible polyurethane foam manufactured above, evaluation samples with sizes conforming to the regulations of each physical property item were cut out from the core part within 5 cm from all surfaces other than the top surface. The measurement of each physical property item was carried out by the following methods.

[0065] (1) Apparent density (density) The apparent density was measured in accordance with JIS K7222:2005. (2) Hardness The hardness was measured in accordance with JIS K6400-2:2012 6.7 D method. (3) Rebound resilience The rebound resilience was measured in accordance with JIS K6400-3:2011. (4) Tensile strength, elongation, tear strength The tensile strength was measured in accordance with JIS K6400-5:2012 3. The elongation was measured in accordance with JIS K6400-5:2012 3. The tear strength was measured in accordance with JIS K6400-5:2012. The test piece was made into a No. 4-shaped notchless angle test piece using a punching jig in accordance with JIS K 6400-1. (5) Air permeability The air permeability was measured in accordance with JIS K6400-7:2012 B method. (6) Compression residual strain The compression residual strain was measured in accordance with JIS K6400-4:2004 4.5.2 A method at 50% compression, 70 °C, and for 22 hours.

[0066] (7) Combustion test based on the railway vehicle A-A standard Test pieces were cut out from the flexible polyurethane foams of the reference examples, comparative examples, and examples. For each test piece, a combustion test was conducted based on the railway vehicle A-A standard. In the combustion test based on the railway vehicle A-A standard, ignition / flaming / smoke / fire intensity during alcohol combustion, afterflame / soot / carbonization (mm) / deformation (mm) after alcohol combustion, and alcohol combustion time (s) were measured.

[0067] Based on the measurement results of the combustion test, evaluation was carried out according to the following criteria. Samples for which the combustion test was not conducted were indicated as "-". Pass: Meets the flame retardancy criteria Fail: Does not meet the flame retardancy criteria

[0068] (8) Fire resistance test (aircraft FAR 25.853 test) Test pieces were cut out from the flexible polyurethane foams of the reference example and Example 8. For each test piece, a fire resistance test specified in FAR 25.853 for aircraft interiors was conducted. In the fire resistance test, the extinguishing time (s) / burning length (inch) / drop extinguishing time (s) in the vertical test were measured.

[0069] Based on the measurement results of the fire resistance test, evaluation was carried out according to the following criteria. Samples for which the fire resistance test was not conducted were indicated as "-". Pass: Meets the passing criteria of the standard Fail: Does not meet the passing criteria of the standard

[0070] 3. Results The evaluation results are also shown in Table 1. Examples 1 to 6 satisfy the following requirement (a). Requirement (a): A flexible polyurethane foam obtained from a composition for producing a polyurethane foam, which comprises a polyol composition A containing an unsaturated carboxylic acid partial ester of a polyol and an aromatic-containing polyester polyol, and an isocyanate. Examples 1 to 6 had good physical properties as flexible polyurethane foams. Examples 1 to 6, Examples 4 and 5 were flame-retardant polyurethane foams. It was suggested that Examples 1 to 6 achieved both good physical properties and flame retardancy and were suitable for practical use.

[0071] In contrast, the composition for producing a polyurethane foam of the comparative example did not contain polyol composition A and did not satisfy the above requirement (a). The flexible polyurethane foam of Comparative Example 1 failed the flame retardancy evaluation. In addition, the composition for producing a polyurethane foam of the reference example needs to be improved in that it uses polyol 5 containing a melamine-based flame retardant.

[0072] Among Examples 1 to 6, Examples 1 and 2 in which the amount of polyol composition A is different are compared. Example 1 is an example in which 10 parts by mass of polyol composition A was used when the total amount of polyols was 100 parts by mass. In Example 1 (N = 2), as a result of the combustion test based on the A-A standard of the railway vehicle, through holes were locally opened. The dimensions of the through holes were 20 mm and 16 mm, respectively. Example 2 is an example in which 18.3 parts by mass of polyol composition A was used when the total amount of polyols was 100 parts by mass. In Example 2 (N = 2), as a result of the combustion test based on the A-A standard of the railway vehicle, through holes were locally opened. The dimensions of the through holes were 157 mm and 162 mm, respectively. From these results, it was suggested that the flame retardancy can be further improved by setting the amount of polyol composition A to, for example, 20 parts by mass or less. The reason is not clear, but since the air permeability of Example 1 is smaller than that of Example 2, it is possible that the air permeability decreased with the reduction of the amount of polyol composition A, making it difficult to burn. Note that the present disclosure is not limited to this speculative reason.

[0073] Among Examples 1 to 6, Examples 1 and 3 that differ in the presence or absence of a flame retardant are compared. Example 1 is an example that does not contain a flame retardant other than the polyol composition A. In Example 1 (N = 2), as a result of the combustion test based on the A-A standard of the railway vehicle, through-holes were locally opened. The dimensions of the through-holes were 20 mm and 16 mm, respectively. Example 3 is an example that contains Flame Retardant 2 as a flame retardant other than the polyol composition A. In Example 3 (N = 2), as a result of the combustion test based on the A-A standard of the railway vehicle, through-holes were locally opened. The dimensions of the through-holes were 149 mm and 150 mm, respectively. From these results, it was suggested that when using the polyol composition A, the flame retardancy can be further improved without using other flame retardants in combination. The fact that the flame retardancy can be improved without using a flame retardant in combination is a surprising result. Although the reason is not clear, since the air permeability of Example 1 is smaller than that of Example 3, there is a possibility that the air permeability is reduced by not using a flame retardant, making it difficult to burn. Note that the present disclosure is not limited to this speculative reason.

[0074] Among Examples 1 to 6, Examples 1 and 6 in which the amount of Polyol 1 (a polyether polyol having a weight average molecular weight of 6000 or more) is different are compared. Example 1 is an example in which 25.3 parts by mass of a polyether polyol having a weight average molecular weight of 6000 or more is used when the total amount of the polyol is 100 parts by mass. The compression residual strain of Example 1 was 17.7%. Example 6 is an example in which 50 parts by mass of a polyether polyol having a weight average molecular weight of 6000 or more is used when the total amount of the polyol is 100 parts by mass. The compression residual strain of Example 6 was 7.1%. From these results, it was suggested that the compression residual strain can be reduced by using, for example, 30 parts by mass or more of a polyether polyol having a weight average molecular weight of 6000 or more.

[0075] Among Examples 1 to 6, Examples 1, 4, and 5 in which the amount of Polyol 4 (an EO-containing polyether polyol) is different are compared. Example 1 is an example in which 1 part by mass of an EO-containing polyether polyol is used when the total amount of the polyol is 100 parts by mass. The ventilation rate of Example 1 was 71.7 cm 3 / cm 2 / s. Example 4 is an example in which no EO-containing polyether polyol is used (0 parts by mass). The ventilation rate of Example 4 was 71.8 cm 3 / cm 2 / s. Example 5 is an example in which 3 parts by mass of an EO-containing polyether polyol is used when the total amount of the polyol is 100 parts by mass. The ventilation rate of Example 5 was 73.4 cm 3 / cm 2 / s. From these results, it was suggested that the air permeability can be improved by using more than 1 part by mass of the EO-containing polyether polyol.

[0076] 4. Effects of Examples The above examples were able to provide a flame-retardant flexible polyurethane foam. Specifically, it was found that by using the polyol composition A, it is possible to contribute to the reduction or non-use of the amount of the flame retardant added. In addition, Examples 1 to 3, Example 5, and Example 6 passed the flame retardancy of the combustion test based on the A-A standard of railway vehicles. Example 8 passed the fire resistance test (aircraft FAR 25.853 test). Furthermore, the examples were able to ensure various physical properties of the flexible polyurethane foam while ensuring flame retardancy.

[0077] The present disclosure is not limited to the examples described in detail above, and various modifications or changes are possible within the scope of the present disclosure.

Claims

1. A polyol composition A containing an unsaturated carboxylic acid partial ester of a polyol and an aromatic-containing polyester polyol, an isocyanate, A flexible polyurethane foam obtained from a composition for producing a polyurethane foam containing the same.

2. The flexible polyurethane foam according to Claim 1, which is a flame-retardant polyurethane foam.

3. A sheet comprising the flexible polyurethane foam according to Claim 1 or 2.

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