Flame-retardant urethane resin composition and polyurethane foam

Abstract

To provide a flame-retardant urethane resin composition that does not foam in a transverse direction and is to produce a polyurethane foam having high flame retardancy.SOLUTION: A flame-retardant urethane resin composition contains a polyol compound, a polyisocyanate compound, a catalyst, a foamer, and a liquid flame retardant, the catalyst containing an amine foaming catalyst, and the isocyanate index being 150 or more.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a flame-retardant urethane resin composition and a polyurethane foam.

Background Art

[0002] Polyurethane foam is utilized for heat insulation and dew condensation prevention of building members such as ceilings, roofs, and wall surfaces of apartment houses, detached houses, commercial buildings, etc. by virtue of its excellent heat insulation property. Polyurethane foam is formed by spraying a flame-retardant urethane resin composition containing a polyol compound and a polyisocyanate compound onto the surface of each structure and causing it to foam and cure.

[0003] Although polyurethane foam is lightweight, it is an organic substance and thus flammable. To improve this, a highly flame-retardant polyurethane foam is required. As a means for enhancing the flame retardancy of polyurethane foam, for example, there is a method of forming an isocyanurate ring in a flame-retardant urethane resin composition as in Patent Document 1.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, a polyurethane foam with a high degree of allophanation has improved flame retardancy but deteriorated foamability, and there are problems such as deteriorated workability due to so-called lateral expansion, i.e., expansion in a direction perpendicular to the thickness direction, and peeling occurring after spraying onto an object. Therefore, an object of the present invention is to provide a flame-retardant urethane resin composition for producing a polyurethane foam that suppresses lateral expansion and has good flame retardancy.

Means for Solving the Problems

[0006] As a result of intensive studies by the present inventors to solve the above problems, a flame-retardant urethane resin composition containing a polyol compound, a catalyst, a foaming agent, and a liquid flame retardant, wherein the catalyst contains an amine-based foaming catalyst and the isocyanate index is 150 or more, has been found to be able to solve the above problems, and the present invention has been completed.

[0007] The present invention has the following gists [1] to

[13] . [1] A flame-retardant urethane resin composition containing a polyol compound, a polyisocyanate compound, a catalyst, a foaming agent, and a liquid flame retardant, wherein the catalyst contains an amine-based foaming catalyst and the isocyanate index is 150 or more. [2] The flame-retardant urethane resin composition according to [1], wherein the amine-based foaming catalyst has two or more nitrogen atoms in the molecule or has one or more nitrogen atoms and one or more oxygen atoms in the molecule. [3] The flame-retardant urethane resin composition according to [1] or [2], which contains 2 parts by mass or more of the amine-based foaming catalyst per 100 parts by mass of the polyol compound. [4] The flame-retardant urethane resin composition according to any one of [1] to [3], wherein the amine-based foaming catalyst contains an aromatic amine represented by the following general formula (1). JPEG2025083559000001.jpg5062 (In the general formula (1), R 1 , R 2 , R 3 and R 4 each independently represents an alkyl group or a hydrogen atom.) [5] The flame-retardant urethane resin composition according to any one of [1] to [4], wherein the amine-based foaming catalyst contains a tertiary amine represented by the following general formula (2). JPEG2025083559000002.jpg19138 (In the general formula (2), k is an integer from 0 to 3, and R 11 to R 14represents a saturated hydrocarbon group having 1 to 2 carbon atoms. Y represents an oxygen atom or -NCH 3 -. X 1 , X 2 represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 2 carbon atoms, or an oxygen atom. In the case of an oxygen atom, it binds to each of R 12 , R 13 to form a morpholine skeleton. ) [6] The flame-retardant urethane resin composition according to any one of [1] to [5], wherein the amine-based foaming catalyst contains a guanidine derivative represented by the following general formula (3). JPEG2025083559000003.jpg4270 (In the general formula (3), R 6 , R 7 , R 8 and R 9 each independently represents an alkyl group. ) [7] The flame-retardant urethane resin composition according to any one of [1] to [6], which contains a trimerization catalyst as the catalyst. [8] The flame-retardant urethane resin composition according to any one of [1] to [7], wherein the foaming agent contains water, and the water content measured by a Karl Fischer apparatus in the polyol composition constituting the flame-retardant urethane resin composition is 0.1 to 3% by mass. [9] The flame-retardant urethane resin composition according to any one of [1] to [8], which contains 50 parts by mass or more of aromatic polyester polyol per 100 parts by mass of the polyol compound.

[10] The flame-retardant urethane resin composition according to any one of [1] to [9], which is used for spraying applications.

[11] The flame-retardant urethane resin composition according to any one of [1] to

[10] , wherein the catalyst contains a metal catalyst as a urethanization catalyst.

[12] The flame-retardant urethane resin composition according to any one of [1] to

[11] , which substantially does not contain an inorganic filler.

[13] A polyurethane foam formed from the flame-retardant urethane resin composition according to any one of [1] to

[12] .

Advantages of the Invention

[0008] According to the present invention, it is possible to provide a flame-retardant urethane resin composition for producing a polyurethane foam that suppresses lateral expansion and has good flame retardancy.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, the present invention will be described in detail. [Flame-Retardant Urethane Composition] The flame-retardant urethane resin composition of the present invention contains a polyol compound, a polyisocyanate compound, a catalyst, a foaming agent, and a liquid flame retardant.

[0010] (Polyol Compound) The flame-retardant urethane resin composition of the present invention contains a polyol compound as a raw material for the polyurethane foam. Examples of the polyol compound used in the present invention include polylactone polyol, polycarbonate polyol, aromatic polyol, alicyclic polyol, aliphatic polyol, polyester polyol, polymer polyol, and polyether polyol.

[0011] Examples of the polylactone polyol include polypropionolactone glycol, polycaprolactone glycol, and polyvalerolactone glycol. Examples of the polycarbonate polyol include polyols obtained by a dealcoholization reaction of a hydroxyl group-containing compound such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, octanediol, and nonanediol with ethylene carbonate, propylene carbonate, or the like.

[0012] Examples of the aromatic polyol include bisphenol A, bisphenol F, phenol novolak, and cresol novolak. Examples of alicyclic polyols include cyclohexanediol, methylcyclohexanediol, isophoronediol, dicyclohexylmethanediol, dimethyldicyclohexylmethanediol, and the like. Examples of aliphatic polyols include ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, and the like.

[0013] Examples of polyester polyols include polymers obtained by dehydration condensation of polybasic acids and polyhydric alcohols, and condensates of hydroxycarboxylic acids and the polyhydric alcohols, etc. Examples of polybasic acids include adipic acid, azelaic acid, sebacic acid, isophthalic acid (m-phthalic acid), terephthalic acid (p-phthalic acid), succinic acid, and the like. Examples of polyhydric alcohols include bisphenol A, ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, diethylene glycol, 1,6-hexanediol, neopentyl glycol, and the like. Examples of hydroxycarboxylic acids include castor oil, reaction products of castor oil and ethylene glycol, and the like.

[0014] Examples of polymer polyols include polymers obtained by graft polymerization of ethylenically unsaturated compounds such as acrylonitrile, styrene, methyl acrylate, and methacrylate to aromatic polyols, alicyclic polyols, aliphatic polyols, polyester polyols, etc., polybutadiene polyols, or hydrogenated products thereof, and the like.

[0015] Examples of the polyether polyol include polymers obtained by ring-opening polymerization of at least one alkylene oxide having 2 to 6 carbon atoms, specifically, at least one of ethylene oxide, propylene oxide, tetrahydrofuran, etc. in the presence of at least one low molecular weight active hydrogen compound having two or more active hydrogens such as polyhydric alcohols. Examples of the alkylene oxide include at least one of ethylene oxide and propylene oxide. Examples of the low molecular weight active hydrogen compound having two or more active hydrogens include diols such as bisphenol A, ethylene glycol, propylene glycol, butylene glycol, 1,6 - hexanediol; triols such as glycerin, trimethylolpropane; tetra - to octavalent alcohols such as pentaerythritol, sorbitol, mannitol, sorbitan, diglycerin, dipentaerythritol, sucrose, glucose, mannose, fructose, methyl glucoside and its derivatives; polyols such as phloroglucinol, cresol, pyrogallol, catechol, hydroquinone, bisphenol A, bisphenol F, bisphenol S, 1,3,6,8 - tetrahydroxynaphthalene, and 1,4,5,8 - tetrahydroxyanthracene; castor oil polyol; polyfunctional (e.g., functional group number 2 to 100) polyols such as (co)polymers of hydroxyalkyl (meth)acrylate and polyvinyl alcohol; condensates of phenol and formaldehyde (novolac); amines such as ethylenediamine and butylenediamine.

[0016] As the polyol compound used in the present invention, polyester polyol and polyether polyol are preferable. Further, a polyol compound having two hydroxyl groups is preferable. Among them, from the viewpoint of enhancing the flame retardancy of the polyurethane foam, an aromatic polyester polyol which is a polyester polyol having an aromatic ring is preferable. The aromatic polyester polyol is preferably a condensate of an aromatic dicarboxylic acid such as o-phthalic acid (phthalic acid), m-phthalic acid (isophthalic acid), p-phthalic acid (terephthalic acid), naphthalenedicarboxylic acid and glycol. Among them, from the viewpoint of enhancing the flame retardancy of the polyurethane foam, particularly the performance of not spreading combustion, the aromatic polyester polyol more preferably contains a phthalic acid-based polyester polyol which is a condensate of phthalic acid and glycol, and further preferably contains at least one selected from a p-phthalic acid-based polyester polyol which is a condensate of p-phthalic acid and glycol and an o-phthalic acid-based polyester polyol which is a condensate of o-phthalic acid and glycol.

[0017] When the polyol compound contains an aromatic polyester polyol, its content is not particularly limited, but it is preferably 50 parts by mass or more, more preferably 70 parts by mass or more, and further preferably 100 parts by mass with respect to 100 parts by mass of the polyol compound in the flame-retardant urethane resin composition.

[0018] The hydroxyl value of the polyol compound is preferably 20 to 300 mgKOH / g, more preferably 30 to 250 mgKOH / g, and further preferably 50 to 220 mgKOH / g. When the hydroxyl value of the polyol is below the above upper limit value, the viscosity of the polyol composition is likely to decrease, which is preferable from the viewpoint of handleability and the like. On the other hand, when the hydroxyl value of the polyol is above the above lower limit value, the crosslink density of the polyurethane foam increases, resulting in higher strength. The hydroxyl value of the polyol compound can be measured according to JIS K 1557-1:2007.

[0019] (Polyisocyanate compound) As the polyisocyanate compound contained in the flame-retardant urethane resin composition of the present invention, various polyisocyanate compounds such as aromatic, alicyclic, and aliphatic polyisocyanate compounds having two or more isocyanate groups can be used.

[0020] Examples of the aromatic polyisocyanate include phenylenediisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, dimethyldiphenylmethane diisocyanate, triphenylmethane triisocyanate, naphthalene diisocyanate, and polymethylene polyphenyl polyisocyanate (polymeric MDI).

[0021] Examples of the alicyclic polyisocyanate include cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and dimethyldicyclohexylmethane diisocyanate. Examples of the aliphatic polyisocyanate include methylene diisocyanate, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, and hexamethylene diisocyanate.

[0022] Among these, from the viewpoints of ease of handling, speed of reaction, physical properties of the resulting polyurethane foam, and low cost, it is preferable to use an aromatic polyisocyanate, and it is more preferable to use liquid diphenylmethane diisocyanate (MDI). As the liquid MDI, crude MDI (also referred to as polymeric MDI) may be used. Specific commercially available products of liquid MDI include "44V-10", "44V-20" (manufactured by Sumika Covestro Polyurethane Co., Ltd.), "Millionate MR-200" (Nippon Polyurethane Industry), and the like. Also, MDI containing uretonimine (for example, "Millionate MTL" as a commercially available product: manufactured by Nippon Polyurethane Industry) may be used. In addition to the liquid MDI, other polyisocyanate compounds may be used in combination, and as the polyisocyanate compound to be used in combination, polyisocyanate compounds known in the technical field of polyurethane can be used without limitation. Further, a part of the isocyanate active groups in the polyisocyanate may be reacted with a hydroxyl group-containing compound and subjected to a treatment for enhancing the affinity with the polyol in advance and then used.

[0023] (Isocyanate Index) The isocyanate index of the flame-retardant urethane resin composition of the present invention is 150 or more. When the isocyanate index of the composition is less than 150, it is difficult to improve the flame retardancy of the polyurethane foam formed from the composition, particularly the difficulty of flame spread. Further, although lateral expansion is likely to occur by increasing the index, the use of an amine-based foaming catalyst described later can appropriately prevent lateral expansion. Considering these facts, the isocyanate index is preferably 200 or more, more preferably 250 or more, and even more preferably 300 or more. Also, regarding the upper limit, the isocyanate index is not particularly limited, but is preferably 700 or less, more preferably 650 or less, and even more preferably 600 or less.

[0024] The isocyanate index (INDEX) is calculated by the following method. INDEX = number of equivalents of polyisocyanate ÷ (number of equivalents of polyol + number of equivalents of water) × 100 Here, Equivalent number of polyisocyanate = Number of parts of polyisocyanate used × NCO content rate (%) × 100 / NCO molecular weight Equivalent number of polyol = OHV × Number of parts of polyol used ÷ Molecular weight of KOH, where OHV is the hydroxyl value (mgKOH / g) of the polyol, Equivalent number of water = Number of parts of water used × Number of OH groups of water / Molecular weight of water That is. In the above formulas, the unit of the number of parts used is weight (g), the molecular weight of the NCO group is 42, the NCO content rate represents the ratio of the NCO group in the polyisocyanate compound in mass %, for the convenience of unit conversion in the above formulas, the molecular weight of KOH is taken as 56100, the molecular weight of water is 18, and the number of OH groups of water is 2.

[0025] (Catalyst) The catalyst in the flame - retardant urethane resin composition of the present invention contains an amine - based foaming catalyst. The foaming catalyst plays a role in promoting the foaming of the flame - retardant urethane resin composition. By containing an amine - based foaming catalyst as the foaming catalyst, the foamability of the composition is improved, the lateral expansion when the composition is sprayed onto an object is prevented, and when the composition is sprayed onto an object to form a polyurethane foam, peeling of the foam from the object and the like can be prevented.

[0026] <Amine - based foaming catalyst> As the amine - based foaming catalyst used in the present invention, it is preferably a compound having two or more nitrogen atoms in the molecule, or a compound having one or more nitrogen atoms and one or more oxygen atoms in the molecule. Generally, a catalyst having an amino group tends to preferentially promote resinification when there is a linear hydrocarbon with 4 or more carbon atoms between heteroatoms (N, O), or when the heteroatom of the ring - forming atoms consists only of nitrogen atoms (for example, an imidazole ring). Therefore, the amine - based foaming catalyst generally has no linear hydrocarbon group with 4 or more carbon atoms between heteroatoms (N, O), and also has no hetero - ring in which the heteroatom of the ring - forming atoms consists only of nitrogen atoms. Specific examples of the amine - based foaming catalyst include aromatic amines, tertiary amines, and guanidine derivatives.

[0027] As the aromatic amine, a compound having at least two amino groups is preferred, and an aromatic amine having a diaminophenyl skeleton in which two amino groups are bonded to one benzene ring is more preferred. Specifically, a compound represented by the following general formula (1) is preferred.

[0028]

Chemical formula

[0029] R 1 ~R 4 The alkyl group is, for example, an alkyl group having 1 to 16 carbon atoms, preferably 1 to 4 carbon atoms. The alkyl group may be linear, branched, or have a cyclic structure. Specific examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, pentyl group, neopentyl group, isopentyl group, sec-pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, etc. Among these, from the viewpoints of stability and foaming property, methyl group and ethyl group are preferred. In general formula (1), it is preferable that R 1 , R 2 , R 4 are alkyl groups and R 3 is a hydrogen atom, and it is more preferable that R 1 , R 2 , R 4 are either a methyl group or an ethyl group and R 3 is a hydrogen atom. Among them, it is most preferable that the above R 1 , R 2 , R 4Among the alkyl groups, diethyltoluenediamine in which any one of them is a methyl group and the remaining two are ethyl groups is more preferable.

[0030] As the tertiary amine, a compound having two or more tertiary amino groups is preferable, and specifically, a compound represented by the following general formula (2) is preferable.

[0031]

Chemical formula

[0032] When X 1 is an oxygen atom, it is the nitrogen atom bonded to R 11 , R 11 , and further forms a morpholine skeleton together with R 12 . In this case, R 11 , R 12 both become -CH 2 CH 2 -. When X 2 is an oxygen atom, it is the nitrogen atom bonded to R 14、 R 14 , and further forms a morpholine skeleton together with R 13 . In this case, R 13 , R 14 both become -CH 2 CH 2 -. When both X 1 , X 2 are oxygen atoms and form a morpholine skeleton, Y is preferably an oxygen atom. X 1 , X 2When forming a morpholine skeleton, a specific compound is preferably 2,2'-dimorpholinodiethyl ether.

[0033] Also, X 1 and X 2 are preferably a hydrogen atom, a hydroxyl group, or an alkoxy group having 1 to 2 carbon atoms. In that case, the tertiary amine is preferably a compound represented by the following (2-1). [Chemical formula] (In the general formula (2-1), m represents an integer of 1 to 3, and n represents an integer of 0 to 1. R 14 represents a divalent saturated hydrocarbon group having 1 to 2 carbon atoms. X 2 represents a hydrogen atom, a hydroxyl group, or an alkoxy group having 1 to 2 carbon atoms.) Examples of the compound represented by the general formula (2-1) include N,N,N',N'',N''-pentamethyldiethylenetriamine, N,N,N',N'',N''',N'''-hexamethyltriethylenetetramine, N,N,N'-trimethyl-N'-(2-hydroxyethyl)bis(2-aminoethyl)ether, bis(2-dimethylaminoethyl)ether, N,N',N'-trimethyl-N-(2-methoxyethyl)ethylenediamine, and the like. Also, in the general formula (2-1), m is more preferably 1, n is preferably 1, and X 2 is preferably a hydrogen atom or a hydroxyl group. As the tertiary amine used in the present invention, N,N,N'-trimethyl-N'-(2-hydroxyethyl)bis(2-aminoethyl)ether and bis(2-dimethylaminoethyl)ether are preferable. Among these tertiary amines, N,N,N'-trimethyl-N'-(2-hydroxyethyl)bis(2-aminoethyl)ether is particularly preferable from the viewpoint of enhancing the storage stability of the flame-retardant urethane resin composition.

[0034] The tertiary amine may be other than the compound represented by the above general formula (2), and examples thereof also include compounds having only one tertiary amino group. Examples of the compound having only one tertiary amino group include dimethylaminoethoxyethanol.

[0035] The guanidine derivative is a compound having a guanidine skeleton, and specific examples thereof include tetraalkylguanidine. Tetraalkylguanidine is N,N,N’,N’-tetraalkylguanidine in which a total of four hydrogen atoms bonded to the nitrogen atoms at the 1-position and 3-position are each independently substituted with an alkyl group. Specific examples of the tetraalkylguanidine include compounds represented by the following general formula (3).

[0036]

Chemical formula

[0037] R 6 , R 7 , R 8 and R 9 The alkyl groups of are, for example, alkyl groups having 1 to 16 carbon atoms, preferably 1 to 4 carbon atoms. The alkyl group may be linear, may have a branch, or may have a cyclic structure. Specific examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, pentyl group, neopentyl group, isopentyl group, sec-pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group and the like. Among these, from the viewpoints of stability and foaming property, the methyl group is preferable, and N,N,N',N'-tetramethylguanidine in which all of the above four alkyl groups are methyl groups is more preferable.

[0038] The above amine-based foaming catalyst may be used alone or in combination of two or more. However, from the viewpoint of foamability, it is also preferable to use two or more in combination. When used in combination, it is preferable to use a combination of the above aromatic amine and tertiary amine. The content of the above amine-based foaming catalyst is preferably 2 parts by mass or more, more preferably 4 parts by mass or more, and still more preferably 6 parts by mass or more with respect to 100 parts by mass of the polyol compound. By setting the content of the amine-based foaming catalyst to the above lower limit or more, the foamability of the composition becomes good, preventing lateral foaming and suppressing lateral expansion. Also, the upper limit of the content of the amine-based foaming catalyst is not particularly limited, but is preferably 30 parts by mass or less, more preferably 25 parts by mass or less, and still more preferably 20 parts by mass or less with respect to 100 parts by mass of the polyol compound.

[0039] <Other catalysts> The catalyst used in the present invention may contain a catalyst other than the above-mentioned amine-based foaming catalyst. In that case, it is preferable to contain a trimerization catalyst.

[0040] The trimerization catalyst is a catalyst that promotes trimerization to form isocyanurate bonds. In the flame-retardant urethane resin composition, by promoting trimerization, the flame retardancy and the difficulty of flame spread of the polyurethane foam are improved. As the trimerization catalyst, aromatic compounds such as tris(dimethylaminomethyl)phenol, 2,4-bis(dimethylaminomethyl)phenol, 2,4,6-tris(dialkylaminoalkyl)hexahydro-S-triazine, potassium acetate, sodium acetate, potassium 2-ethylhexanoate, sodium 2-ethylhexanoate, potassium formate, potassium octylate, sodium octylate and other alkali metal salts, aziridines such as 2-ethylaziridine, lead compounds such as lead naphthenate, lead octylate, alcoholate compounds such as sodium methoxide, phenolate compounds such as potassium phenoxide, tertiary ammonium salts such as trimethylammonium salt, triethylammonium salt, triphenylammonium salt, quaternary ammonium salts such as tetramethylammonium salt, tetraethylammonium salt, tetraphenylammonium salt, etc. can be used. Among these, quaternary ammonium salts are preferred. When using a quaternary ammonium salt, even if a hydrofluorolefin compound such as hydrochlorofluorolefin is used as the foaming agent, the catalytic activity is maintained well, so that the trimerization proceeds appropriately and the flame retardancy and the like are improved. The trimerization catalyst may be used alone or in combination of two or more.

[0041] The content of the trimerization catalyst is not particularly limited, but it is preferably in the range of 1 to 15 parts by mass, more preferably in the range of 1.5 to 13 parts by mass, and even more preferably in the range of 2 to 10 parts by mass with respect to 100 parts by mass of the polyol compound. By setting the content of the trimerization catalyst within the above range, isocyanurate bonds are appropriately formed and the flame retardancy is improved.

[0042] The flame-retardant urethane resin composition of the present invention may contain a urethanization catalyst in addition to the above-described trimerization catalyst. The urethanization catalyst is a catalyst that promotes the reaction between the polyol compound and the polyisocyanate compound. As the urethanization catalyst, it is preferable to contain a metal catalyst such as a tin compound or a bismuth compound.

[0043] Examples of the tin compound include stannous octylate, dibutyltin diacetate, dibutyltin dilaurate, etc. Examples of the bismuth compound include bismuth neodecanoate, bismuth octylate, etc.

[0044] From the viewpoint of initial activity, the flame-retardant urethane resin composition of the present invention preferably contains a bismuth compound as a metal catalyst. Among the urethanization catalysts, the content of the metal catalyst is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 4 parts by mass, and still more preferably 0.15 to 3 parts by mass with respect to 100 parts by mass of the polyol compound. When the content of the metal catalyst is not less than the above lower limit value, the initial activity of the flame-retardant urethane resin composition becomes good, and accordingly, the foaming property of the composition also becomes good. On the other hand, when the content of the metal catalyst is not more than the above upper limit value, it becomes possible to effectively prevent the flame-retardant urethane resin composition from foaming laterally when foaming.

[0045] As the urethanization catalyst, in addition to the above-mentioned metal catalyst, an amino compound, an acetylacetone metal salt, etc. may be contained. Examples of the amino compound include imidazole compounds such as 1-methylimidazole, 1,2-dimethylimidazole, 1-isobutyl-2-methylimidazole, and an imidazole compound in which the secondary amine functional group in the imidazole ring is substituted with a cyanoethyl group. As the imidazole compound, 1,2-dimethylimidazole is preferred.

[0046] When the urethanization catalyst contains an amino compound, the content of the amino compound is preferably 2 to 14 parts by mass, more preferably 3 to 10 parts by mass, and still more preferably 3.5 to 9 parts by mass with respect to 100 parts by mass of the polyol compound.

[0047] Examples of the acetylacetone metal salts include aluminum acetylacetonate, iron acetylacetonate, copper acetylacetonate, zinc acetylacetonate, beryllium acetylacetonate, chromium acetylacetonate, indium acetylacetonate, manganese acetylacetonate, molybdenum acetylacetonate, titanium acetylacetonate, cobalt acetylacetonate, vanadium acetylacetonate, zirconium acetylacetonate, and the like.

[0048] The urethanization catalyst contained in the flame-retardant urethane resin composition of the present invention may be used alone or in combination of two or more. When a metal catalyst is contained as the urethanization catalyst, from the viewpoint of improving the foamability when forming a polyurethane foam by spraying the flame-retardant urethane resin composition, it is preferable to contain the above-mentioned bismuth compound. Further, when a urethanization catalyst other than the metal catalyst is contained in addition to the above metal catalyst, it is preferable to use a combination of a bismuth compound and an amino compound as the urethanization catalyst, and a combination of a bismuth compound and an imidazole compound is more preferable.

[0049] The content of the urethanization catalyst in the flame-retardant urethane resin composition of the present invention is, for example, 1 part by mass or more, preferably 2 parts by mass or more, based on 100 parts by mass of the polyol compound. By setting the content to be not less than the above lower limit value, the reaction between the polyol compound and the polyisocyanate compound can be promoted at an appropriate reaction rate while improving the foamability. Further, in order to improve the reaction rate and make it suitable for spraying applications, the above content of the urethanization catalyst is more preferably 3 parts by mass or more, and even more preferably 4 parts by mass or more. Further, from the viewpoint of obtaining foamability and reactivity commensurate with the catalyst content, the above content of the urethanization catalyst is preferably 15 parts by mass or less, more preferably 12 parts by mass or less, and even more preferably 10 parts by mass or less.

[0050] (Flame retardant) The flame-retardant polyurethane resin composition of the present invention contains a liquid flame retardant. Thereby, the flame retardancy of the polyurethane foam formed from the flame-retardant polyurethane resin composition is improved. Here, the liquid flame retardant is a flame retardant that is liquid at 23°C. Examples of the liquid flame retardant include phosphate-based flame retardants such as monophosphoric acid esters and condensed phosphoric acid esters. The monophosphoric acid ester is not particularly limited, and examples thereof include trimethyl phosphate, triethyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, tris(β-chloropropyl) phosphate, and the like. The condensed phosphoric acid ester is not particularly limited, and examples thereof include resorcinol polyphenyl phosphate (trade name CR-733S), bisphenol A polycresyl phosphate (trade name CR-741), aromatic condensed phosphoric acid ester (trade name CR747), and the like. The liquid flame retardant is preferably a monophosphoric acid ester, and more preferably tris(β-chloropropyl) phosphate. The content of the liquid flame retardant is preferably 3 to 70 parts by mass, more preferably 5 to 60 parts by mass, and still more preferably 10 to 50 parts by mass with respect to 100 parts by mass of the polyol compound. When the content of the liquid flame retardant is at least the lower limit value, it becomes easier to maintain the flame retardancy of the polyurethane foam even when a foaming catalyst is used. In addition, as the liquid component increases, even if a solid component such as a solid flame retardant described later enters the flame-retardant polyurethane resin composition, it becomes possible to ensure the fluidity of the composition. When the content of the liquid flame retardant is at most the upper limit value, the polyurethane foam is easily manufactured because foaming is not inhibited.

[0051] The flame retardant used in the present invention may have a solid flame retardant in addition to the above-described liquid flame retardant. The solid flame retardant is a flame retardant that is solid at room temperature. Examples of the solid flame retardant include red phosphorus-based flame retardants, phosphate-containing flame retardants, bromine-containing flame retardants, chlorine-containing flame retardants, antimony-containing flame retardants, boron-containing flame retardants, needle-like fillers, and metal hydroxides. The solid flame retardant is, for example, in powder form.

[0052] <Red phosphorus-based flame retardant> The red phosphorus-based flame retardant may consist of elemental red phosphorus, or may be red phosphorus coated with a resin, metal hydroxide, metal oxide, etc., or a mixture of red phosphorus and a resin, metal hydroxide, metal oxide, etc. The resin for coating or mixing with red phosphorus is not particularly limited, and examples thereof include thermosetting resins such as phenol resin, epoxy resin, unsaturated polyester resin, melamine resin, urea resin, aniline resin, and silicone resin. From the viewpoint of flame retardancy, metal hydroxides are preferable as the compound for coating or mixing. As the metal hydroxide, those described later may be appropriately selected and used.

[0053] <Phosphate-containing flame retardant> Specific examples of the phosphate-containing flame retardant include phosphates composed of salts of various phosphoric acids and at least one metal or compound selected from metals in Groups IA to IVB of the periodic table, ammonia, aliphatic amines, aromatic amines, and heterocyclic compounds containing nitrogen in the ring. The phosphoric acid is not particularly limited, and examples thereof include monophosphoric acid, pyrophosphoric acid, polyphosphoric acid, etc. Examples of the metals in Groups IA to IVB of the periodic table include lithium, sodium, calcium, barium, iron(II), iron(III), aluminum, etc. Examples of the aliphatic amines include methylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, piperazine, etc. Examples of the aromatic amines include aniline, o-toluidine, 2,4,6-trimethylaniline, anisidine, 3-(trifluoromethyl)aniline, etc. Examples of the heterocyclic compounds containing nitrogen in the ring include pyridine, triazine, melamine, etc.

[0054] Specific examples of the phosphate-containing flame retardant include, for example, monophosphates, pyrophosphates, polyphosphates, etc. Here, the polyphosphate is not particularly limited, and examples thereof include ammonium polyphosphate, piperazine polyphosphate, melamine polyphosphate, ammonium amide polyphosphate, aluminum polyphosphate, etc. The phosphate-containing flame retardant may be used alone or in combination of two or more of the above-mentioned ones.

[0055] <Bromine-containing flame retardant> The bromine-containing flame retardant is not particularly limited as long as it is a compound containing bromine in its molecular structure and is solid at normal temperature and pressure. Examples thereof include aromatic compounds containing brominated aromatic rings. Examples of the aromatic compound containing a brominated aromatic ring include monomeric organic bromine compounds such as hexabromobenzene, pentabromotoluene, hexabromobiphenyl, decabromobiphenyl, decabromodiphenyl ether, bis(pentabromophenoxy)ethane, ethylene bis(pentabromophenyl), and ethylene bis(tetrabromophthalimide).

[0056] The aromatic compound containing a brominated aromatic ring may also be a bromine compound polymer. Specifically, brominated polycarbonates such as polycarbonate oligomers produced from brominated bisphenol A, copolymers of the polycarbonate oligomer and bisphenol A, diepoxy compounds produced by the reaction of brominated bisphenol A and epichlorohydrin, etc. are included. Further, brominated epoxy compounds such as monoepoxy compounds obtained by the reaction of brominated phenols and epichlorohydrin, condensates of brominated phenols of brominated polyphenylene ether, brominated bisphenol A and cyanuric chloride, brominated polystyrenes such as uncrosslinked or crosslinked brominated polystyrene, etc. are included. Compounds other than the aromatic compound containing a brominated aromatic ring such as hexabromocyclododecane may also be used. These bromine-containing flame retardants may be used alone or in combination of two or more. Among the above, aromatic compounds containing brominated aromatic rings are preferred, and among them, monomeric organic bromine compounds such as ethylene bis(pentabromophenyl) are more preferred.

[0057] <Chlorine-containing flame retardant> Chlorine-containing flame retardants include those commonly used in polyurethane foams, such as polychlorinated naphthalenes, chlorendic acid, dodecachlorododecahydrodimethanodibenzocyclooctene sold under the trade name "Dechlorane Plus", and the like. <Antimony-containing flame retardants> Examples of antimony-containing flame retardants include antimony oxide, antimonate, pyroantimonate, etc. Examples of antimony oxide include antimony trioxide, antimony pentoxide, etc. Examples of antimonate include sodium antimonate, potassium antimonate, etc. Examples of pyroantimonate include sodium pyroantimonate, potassium pyroantimonate, etc. The antimony-containing flame retardant may be used alone or in combination of two or more. The antimony-containing flame retardant used in the present invention is preferably antimony oxide.

[0058] <Boron-containing flame retardants> Examples of boron-containing flame retardants include borax, boron oxide, boric acid, borate, etc. Examples of boron oxide include diboron trioxide, boron trioxide, diboron dioxide, tetraboron trioxide, tetraboron pentoxide, etc. Examples of borate include borates of alkali metals, alkaline earth metals, elements of Group 4, Group 12, Group 13 of the periodic table, and ammonium. Specifically, alkali metal borates such as lithium borate, sodium borate, potassium borate, cesium borate, alkaline earth metal borates such as magnesium borate, calcium borate, barium borate, zirconium borate, zinc borate, aluminum borate, ammonium borate, etc. The boron-containing flame retardant may be used alone or in combination of two or more. The boron-containing flame retardant used in the present invention is preferably borate, and more preferably zinc borate.

[0059] <Needle-shaped filler> Examples of the acicular filler include potassium titanate whisker, aluminum borate whisker, silicon-containing whisker, wollastonite, sepiolite, zonolite, eleolite, boehmite, asbestos fiber, carbon fiber, graphite fiber, slag fiber, silica fiber, alumina fiber, zirconia fiber, boron nitride fiber, stainless steel fiber, etc. The aspect ratio (length / diameter) of the acicular filler preferably ranges from 5 to 50, more preferably from 10 to 40.

[0060] <Metal hydroxide> Examples of the metal hydroxide include magnesium hydroxide, calcium hydroxide, aluminum hydroxide, iron hydroxide, nickel hydroxide, zirconium hydroxide, titanium hydroxide, zinc hydroxide, copper hydroxide, vanadium hydroxide, tin hydroxide, etc. The metal hydroxide may be used alone or in combination of two or more.

[0061] When containing the solid flame retardant, the content of the solid flame retardant in the flame-retardant urethane resin composition is preferably 3 to 65 parts by mass, more preferably 5 to 60 parts by mass, and further preferably 10 to 40 parts by mass with respect to 100 parts by mass of the polyol compound. By setting the content of the solid flame retardant to be not less than these lower limit values, it becomes easier to exhibit the effect of containing the solid flame retardant and the flame retardancy is enhanced. On the other hand, by setting it to be not more than the upper limit value, foaming is not inhibited by the solid flame retardant.

[0062] (Blowing agent) Specific examples of the blowing agent include, for example, water, low-boiling hydrocarbons, chlorinated aliphatic hydrocarbon compounds, fluorine compounds, hydrochlorofluorocarbon compounds, hydrofluorocarbons, ether compounds, hydrofluoroolefins, etc. Further, examples of the blowing agent include organic physical blowing agents such as mixtures of these compounds, and inorganic physical blowing agents such as nitrogen gas, oxygen gas, argon gas, carbon dioxide gas, etc. Examples of the low-boiling hydrocarbons include propane, butane, pentane, hexane, heptane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane and the like. Examples of the chlorinated aliphatic hydrocarbon compounds include dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, isopentyl chloride and the like. Examples of the fluorine compounds include CHF 3 、CH 2 F 2 、CH 3 F and the like. Examples of the hydrochlorofluorocarbon compounds include trichloromonofluoromethane, trichlorotrifluoroethane, dichloromonofluoroethane (e.g., HCFC141b (1,1-dichloro-1-fluoroethane)), HCFC22 (chlorodifluoromethane), HCFC142b (1-chloro-1,1-difluoroethane) and the like. Examples of the hydrofluorocarbons include HFC-245fa (1,1,1,3,3-pentafluoropropane), HFC-365mfc (1,1,1,3,3-pentafluorobutane) and the like. Examples of the ether compounds include diisopropyl ether and the like. Examples of the hydrofluoroolefins include HFO-1233zd(E) (trans-1-chloro-3,3,3-trifluoropropene), HFO-1234yf (2,3,3,3-tetrafluoro-1-propene), HFO-1336mzz(Z) (cis-1,1,1,4,4,4-hexafluorobut-2-ene), HFO-1224yd(Z) and the like.

[0063] Among the above, as the blowing agent, hydrofluoroolefins, water and the like are preferable, and it is more preferable to use hydrofluoroolefins and water in combination. From the viewpoint of adjusting the density of the foam to a desired range, the content of the foaming agent is preferably 5 to 70 parts by mass, more preferably 10 to 60 parts by mass, and still more preferably 20 to 50 parts by mass with respect to 100 parts by mass of the polyol compound. From the viewpoint of making the density of the polyurethane foam fall within a desired range, the amount of the hydrofluoroolefin used as the foaming agent is preferably 5 to 70 parts by mass, more preferably 8 to 60 parts by mass, and still more preferably 18 to 50 parts by mass with respect to 100 parts by mass of the polyol compound. As the water used as the foaming agent, for example, ion-exchanged water, distilled water, etc. can be appropriately used. The amount of water with respect to 100 parts by mass of the polyol compound is preferably 0.1 to 15 parts by mass, more preferably 0.2 to 5 parts by mass, and still more preferably 0.3 to 3 parts by mass. By setting the water content within the above range, the flame retardancy and foaming properties are well balanced and excellent.

[0064] (Inorganic filler) The flame-retardant urethane resin composition of the present invention may or may not contain an inorganic filler such as the above-described solid flame retardant, etc., but it is preferable not to substantially contain an inorganic filler. By not substantially containing an inorganic filler, it is possible to provide a flame-retardant urethane resin composition in which sediment is less likely to occur during storage, the storage stability is excellent, and wear of the equipment used during use can be suppressed. Further, in the present invention, high flame retardancy can be obtained even without substantially containing an inorganic filler. Here, not substantially containing an inorganic filler means that the content of the inorganic filler is 5% by mass or less, preferably 1% by mass or less, based on the total amount of the flame-retardant urethane resin composition.

[0065] The inorganic filler is a particulate inorganic compound, and examples thereof include a solid flame retardant and an inorganic filler other than the solid flame retardant. The details of the solid flame retardant are as described above. In addition, examples of inorganic fillers other than the solid flame retardant include potassium salts such as silica, diatomaceous earth, alumina, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, basic magnesium carbonate, calcium carbonate, magnesium carbonate, barium carbonate, dawsonite, hydrotalcite, calcium sulfate, barium sulfate, calcium silicate, talc, clay, mica, montmorillonite, bentonite, activated clay, sepiolite, imogolite, sericite, glass beads, silica powder, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon powder, charcoal powder, various metal powders, potassium titanate, magnesium sulfate, lead zirconate titanate, aluminum porate, molybdenum sulfide, silicon carbide, various magnetic powders, fly ash, etc.

[0066] (Blowing agent) The flame-retardant urethane resin composition may contain a blowing agent. As the blowing agent, a compound having a polar part and a non-polar part in the molecule and having a surfactant effect can be preferably used. The blowing agent is not particularly limited. For example, surfactants such as polyoxyalkylene blowing agents such as polyoxyalkylene alkyl ethers, and silicone blowing agents such as organopolysiloxanes can be mentioned. Further, as the silicone blowing agent, a graft copolymer of polyoxyalkylene glycol, which is a polymer of ethylene oxide or propylene oxide, and polydimethylsiloxane may be used. Commercially available products can also be used. Specifically, blowing agents such as SH-193 (manufactured by Toray Dow Corning), S-824-02 (manufactured by Nippon Unicar), SZ-1704 (manufactured by Nippon Unicar), F501 (manufactured by Shin-Etsu Chemical Co., Ltd.), SF-2937F (manufactured by Dow Corning Toray Co., Ltd.) can be used. The content of the blowing agent is preferably 0.1 to 15 parts by mass, more preferably 0.5 to 12 parts by mass, and even more preferably 1 to 8 parts by mass with respect to 100 parts by mass of the polyol compound.

[0067] (Other components) The flame-retardant urethane resin composition can contain, as necessary within a range not impairing the object of the present invention, one or more selected from phenolic, amine-based, sulfur-based antioxidants, heat stabilizers, light stabilizers, metal deactivators, antistatic agents, stabilizers, crosslinking agents, lubricants, softeners, pigments, dyes, etc.

[0068] In the flame-retardant urethane resin composition of the present invention, the polyol compound and the polyisocyanate compound react and cure. Therefore, before using the flame-retardant urethane resin composition, the flame-retardant urethane resin composition should be divided into two or more parts to prevent the flame-retardant urethane resin composition from reacting and curing. And when using the flame-retardant urethane resin composition, it is preferable to combine the flame-retardant urethane resin composition divided into two or more parts into one.

[0069] When dividing the flame-retardant urethane resin composition of the present invention into two or more parts, curing does not start with each component of the composition divided into two or more parts alone, and each component may be divided so that the curing reaction starts after mixing each component of the composition. Usually, a two-component type in which the composition is divided into a polyol composition containing a polyol compound and a polyisocyanate composition containing a polyisocyanate compound is preferable.

[0070] The above-described catalyst, liquid flame retardant, foaming agent, and, if necessary, the foam stabilizer may be contained in the polyol composition, may be contained in the polyisocyanate composition, or may be provided separately from the polyol composition and the polyisocyanate composition, but it is preferable to be contained in the polyol composition.

[0071] (Moisture content) When the foaming agent used in the present invention is contained in the polyol composition and the foaming agent contains water, it is preferable that the polyol composition has a water content of 3% by mass or less as measured by a Karl Fischer moisture measuring device. When the water content is 3% by mass or less, the polyurethane foam is less likely to spread combustion, and it becomes easier to adjust the sinking distance of the steel ball in the hot steel ball evaluation to a desired range described later. The above water content is more preferably 2% by mass or less, and even more preferably 1% by mass or less. Also, from the viewpoint of foamability, it is preferable to contain a certain amount or more of water, and the water content is preferably 0.1% by mass or more, and more preferably 0.15% by mass or more.

[0072] (Hot steel ball evaluation) The polyurethane foam formed from the flame-retardant urethane resin composition of the present invention preferably has a sinking distance of the steel ball in the hot steel ball evaluation of 10 mm or less. When the sinking distance of the steel ball is 10 mm or less, the polyurethane foam is less likely to spread combustion when exposed to a fire or the like, and can effectively prevent flame spread. From the viewpoint of effectively preventing flame spread, the sinking distance of the steel ball is more preferably 5 mm or less, and even more preferably 3 mm or less. Note that the hot steel ball evaluation is preferably carried out according to the procedure described in the examples.

[0073] The sinking distance of the steel ball in the above hot steel ball evaluation can be adjusted to a desired value by adjusting the type of polyol compound contained in the flame-retardant urethane resin composition, the content of the flame retardant and water, the type and content of the catalyst, the isocyanate index, etc.

[0074] In the above hot steel ball evaluation, in the test piece, a cavity is formed from the upper surface of the test piece to the inside due to the sinking of the steel ball. The sinking distance of the steel ball means the maximum distance of the cavity in the direction perpendicular to the upper surface of the test piece. Note that portions that maintain their shape despite discoloration due to heat are not subject to the measurement of the sinking distance. In addition, with respect to the sinking distance of the steel ball in the hot steel ball evaluation of the polyurethane foam formed from the above-described flame-retardant urethane resin composition, the measured value obtained by manufacturing the polyurethane foam under the conditions described in the examples from the flame-retardant urethane resin composition and measuring the polyurethane foam is adopted.

[0075] (Manufacturing Method) The manufacturing method of the flame-retardant urethane resin composition is not particularly limited, and examples include a method of preparing a polyol composition and a polyisocyanate composition that are premixed and then mixing the two, and a method of kneading each component constituting the flame-retardant urethane resin composition. Usually, it is produced by mixing a polyol composition and a polyisocyanate composition. The mixing of each component can be performed by a known method, and for example, it can be obtained by using a known apparatus such as a high-pressure foaming machine, a low-pressure foaming machine, a spray foaming machine, and a hand mixer.

[0076] [Polyurethane Foam] The polyurethane foam of the present invention is formed from the above-described flame-retardant urethane resin composition, and specifically, it is obtained by foaming and curing the flame-retardant urethane resin composition.

[0077] (Density) The density of the polyurethane foam is not particularly limited, but it is preferably in the range of 20 to 200 kg / m 3 . By setting the density to 200 kg / m 3 or less, the polyurethane foam becomes lightweight and the workability for structures is improved. Also, by setting it to 20 kg / m 3 or more, it becomes easier to exhibit the desired flame retardancy. From these viewpoints, the density of the polyurethane foam is more preferably in the range of 20 to 100 kg / m 3 , and even more preferably in the range of 23 to 80 kg / m 3 . The density of the polyurethane foam can be measured by the method described in the examples.

[0078] (Applications) The use of the flame-retardant urethane resin composition of the present invention and the polyurethane foam formed from the composition is not particularly limited, but it can be used for filling cavities in structures such as buildings, furniture, automobiles, trains, ships, etc., or for spraying onto the structures. Among them, it is preferably used for spraying onto structures, that is, for spraying applications. Spraying can be carried out using a spraying device and a spray gun. General spraying devices and spray guns spray by evenly reacting the volume ratio of the isocyanate and polyol in the foam stock solution. Therefore, the foam stock solution can be reacted with an isocyanate volume ratio of 1.0 and a polyol in the range of 0.8 - 1.2. Spraying can be carried out by adjusting the temperature of the polyol composition and the polyisocyanate composition in separate containers in the spraying device, colliding and mixing the two at the tip of the spray gun, and atomizing the mixed solution by air pressure. Spraying devices and spray guns are known, and commercially available products can be used. For example, "A - 25" manufactured by GRACO can be used as the spraying device, and "D gun" manufactured by Gasmer can be used as the spray gun.

Examples

[0079] The present invention will be described in more detail by way of examples, but the present invention is not limited by these examples in any way.

[0080] Details of each component used in each example and comparative example are as follows. (Polyol compound) · Aromatic polyester polyol p - phthalic acid - based polyester polyol (manufactured by Kawasaki Chemical Industry Co., Ltd., product name "Maximol RFK - 505", hydroxyl value = 250 mgKOH / g) (Liquid flame retardant) · Phosphate - based flame retardant Tris(β - chloropropyl) phosphate (manufactured by Daihachi Chemical Co., Ltd., product name "TMCPP") (Foam stabilizer) · Silicone - based foam stabilizer (manufactured by Toray Dow Corning Co., Ltd., product name "SH - 193") (Catalyst) (1) Amine-based foaming catalyst (i) Aromatic amine · Diethyltoluenediamine (manufactured by Lonza Japan, product name "Lonza Cure DETDA 80") concentration 100% by mass (ii) Guanidine derivative · N,N,N',N'-Tetramethylguanidine (manufactured by Evonik Japan, product name "POLYCAT 201", mixture with water and ethylene glycol (N,N,N',N'-tetramethylguanidine 60% by mass, ethylene glycol 32% by mass, water 8% by mass)) (iii) Tertiary amine · Tertiary amine A: N,N,N'-trimethyl-N'-(2-hydroxyethyl)bis(2-aminoethyl)ether, concentration about 85% by mass · Tertiary amine B: Bis(2-dimethylaminoethyl)ether (manufactured by Momentive Performance Materials Japan, product name "NIAX Catalyst A-1") concentration about 70% by mass (2) Urethanization catalyst · Amino compound: 1,2-Dimethylimidazole (manufactured by Kao, product name "Kaoizer No. 390") concentration about 65 - 75% by mass · Metal catalyst: Bismuth 2-ethylhexanoate (manufactured by Nitto Kasei, product name "Bi28") concentration about 81 - 90% by mass (3) Trimerization catalyst · Quaternary ammonium salt: Tetramethylammonium 2,2-dimethylpropanoate (manufactured by Air Products, product name "DABCO TMR7") concentration about 45% by mass (Foaming agent) · Water · HFO-1233zd <Hydrofluoroolefin> (manufactured by Honeywell, product name "Solstice LBA") (Polyisocyanate compound) · Aromatic polyisocyanate polymeric MDI (manufactured by Sumika Covestro Urethane Co., Ltd., product name: 44V-20)

[0081] [Examples 1 - 6, Comparative Examples 1 - 2] In a 500 mL polypropylene cup (manufactured by Terao Kaisha), a polyol composition and a polyisocyanate compound were mixed at the ratios shown in Table 1 to obtain a total of 80 g of a flame-retardant urethane resin composition, and the composition was stirred for 2 seconds at a liquid temperature of 10 °C to cause foaming. The measurement methods for the physical properties and characteristics of the flame-retardant urethane resin composition and the polyurethane foam are as follows.

[0082] [Moisture content] The polyol composition was measured using a Karl Fischer moisture measuring device (manufactured by Kyoto Electronics Industry Co., Ltd., product name "MKV-710").

[0083] [Density] The flame-retardant urethane resin composition was foamed as described above, and from the portion of the formed polyurethane foam that protruded from the polypropylene cup, a 50 mm square of the polyurethane foam was cut out and measured based on the mass and volume of the cut-out foam. The foam was cut out from the portion excluding the surface layer of the portion that protruded from the cup. Note that the standard density of the polyurethane foam is 40 kg / m 3 and the density correction coefficient indicating the degree of deviation of the measured value from that standard was calculated using the following calculation formula. Density correction coefficient = Measured value of density (kg / m 3 ) ÷ 40 (kg / m 3 )

[0084] [Cream time (CT)] The cream time (CT) was measured by a conventional method. That is, by hand foaming, a polyol composition and a polyisocyanate component at a liquid temperature of 10 °C and an ambient temperature of 20 °C were mixed and stirred under the conditions of 8000 rpm × 2 seconds. Time measurement was started at the stage when stirring began, and the time until the reaction mixture became cloudy and rose in a cream-like state was taken as the cream time (CT, seconds). Based on the cream time measured as described above, the initial activity was evaluated according to the following evaluation criteria. ○ ··· Cream time is less than 5 seconds × ··· Cream time is 5 seconds or more

[0085] [Foaming behavior] (1) Maximum diameter The flame-retardant urethane resin composition was foamed as described above to form a polyurethane foam. Then, among the polyurethane foam protruding from the polypropylene cup, the length of the portion with the maximum lateral diameter was measured with calipers. (2) Foaming height The flame-retardant urethane resin composition was foamed as described above to form a polyurethane foam. Then, the height from the bottom surface of the polypropylene cup to the apex of the portion protruding from the polypropylene cup was measured with calipers. In addition, the corrected value of the foaming height (hereinafter referred to as "foaming height (after correction)") was calculated using the following calculation formula. Foaming height (after correction) = Measured value of foaming height × Density correction coefficient (3) Behavior evaluation Based on the numerical result obtained by dividing the maximum diameter by the foaming height (after correction), the foaming behavior was evaluated according to the following criteria. Note that the value obtained by dividing the maximum diameter by the foaming height (after correction) is an index indicating the lateral expansion, and the smaller the value, the smaller the lateral expansion. 〇 ··· Less than 0.50 △ ··· 0.50 or more and less than 0.55 × ··· 0.55 or more

[0086] [Flame retardancy] (1) Degree of nitration of the polyurethane foam The degree of nitration was measured for the polyurethane foams prepared in each example and comparative example. The degree of nitration was measured by measuring the infrared absorption spectrum of the polyurethane foam and setting the average intensity in the range of 1900 - 2000 cm -1 to zero, and then calculating the ratio of the maximum peak intensity Ia in the range of 1500 - 1520 cm -1 to the average intensity in the range of 1390 - 1430 cm -1 when the average intensity in the range of 1900 - 2000 cm -1It is the ratio (Ib / Ia) of the maximum peak intensity Ib. The infrared absorption spectrum was measured by the ATR method (total reflection measurement method) for the depth portion from 5 mm to 10 mm from the surface layer of the polyurethane foam. Note that the intensity in the infrared absorption spectrum means the infrared absorption intensity. Also, in the infrared absorption spectrum, the absorption at 1400 cm -1 is the absorption derived from the isocyanurate bond, and the absorption at 1510 cm -1 is the absorption derived from the urethane bond. The measurement was carried out using an infrared spectrophotometer ("Nicolet is5" manufactured by Thermo Fisher Scientific). (2) Hot steel ball evaluation For the polyurethane foams prepared in each example and comparative example, the sinking distance of the steel ball was measured according to the following procedures (i) to (iii). (i) The polyurethane foam was cut into a cube with each side dimension of 50 mm × 50 mm × 30 mm to obtain a test piece. (ii) A steel ball with a diameter of 10.0 mm and a weight of 4.15 g was placed in an electric furnace set at a temperature of 800 °C, and left for 10 minutes or more until the entire steel ball was uniformly heated and changed to red, so that the steel ball temperature was 800 °C. Note that a new steel ball was used. (iii) In an atmosphere of 23 °C, the steel ball heated in the above (ii) was immediately placed on the center of the upper part of the test piece in the above (i), and left until the sinking of the steel ball was completed. Then, the cross-section of the sufficiently cooled test piece was cut, and the sinking distance of the steel ball was measured. Note that in this hot steel ball evaluation, the time from heating the steel ball to placing it on the test piece is within 1 second. Also, as the steel ball, a steel ball made of SUS304 was used. Regarding the electric furnace, for example, a small programmable electric furnace (product name "MMF-1" manufactured by AS ONE) with an inner furnace dimension of 120 mm × 150 mm × 100 mm was used. (3) Flame retardancy evaluation Based on the sinking distance of the steel ball obtained by the above procedures, the flame retardancy of the polyurethane foam was evaluated according to the following criteria. ◎ ··· The sinking distance of the steel ball is less than 1 mm 〇···The sinking distance of the steel balls is 1 mm or more and less than 6 mm ×···In cases other than the above ◎ and 〇

[0087] [Workability] According to the formulation in Table 1, a polyol composition consisting of a polyol compound, a trimerization catalyst, a urethanization catalyst, a foam stabilizer, a flame retardant, and a blowing agent, and a polyisocyanate composition consisting of MDI were each introduced into a spraying device (manufactured by GRACO: A-25). The temperature was adjusted inside the device, and using a spray gun (manufactured by GRACO: AP gun), a flame-retardant urethane resin composition composed of a mixture of the polyol composition and the polyisocyanate composition was sprayed onto a plywood board with a length of 600 mm and a width of 300 mm at once to a thickness of 20 mm, and the degree of foaming in the lateral direction was evaluated according to the following criteria. ◎···The elongation in the lateral direction is small. 〇···The elongation in the lateral direction is large, but there is no warping or peeling from the plywood board. ×···The elongation in the lateral direction is large, and there is warping from the plywood board and partial peeling of the polyurethane foam.

[0088] Using the obtained polyurethane foam, each of the above evaluations was carried out. The evaluation results of each item are shown in Table 1.

[0089]

Table 1

[0090] Note that the parts by mass of each catalyst are parts by mass as a product.

[0091] As described above, in each example, by containing an amine-based foaming catalyst in the flame-retardant urethane resin composition and having an isocyanate index of 150 or more in the composition, the lateral elongation could be suppressed, and a polyurethane foam excellent in flame retardancy could be obtained. In addition, in each of the comparative examples, regarding the isocyanate index of the flame-retardant urethane resin composition, since it was 150 or more as in each of the examples, a polyurethane foam excellent in flame retardancy was obtained. However, since the amine-based foaming catalyst was not contained in the flame-retardant urethane resin composition, lateral expansion occurred.

Claims

1. A flame-retardant urethane resin composition comprising a polyol compound, a polyisocyanate compound, a catalyst, a foaming agent, and a liquid flame retardant, The catalyst comprises an amine-based foaming catalyst; A flame-retardant urethane resin composition having an isocyanate index of 150 or more.

2. 2. The flame-retardant urethane resin composition according to claim 1, wherein the amine-based foaming catalyst has two or more nitrogen atoms in the molecule, or has one or more nitrogen atoms and one or more oxygen atoms in the molecule.

3. 3. The flame-retardant urethane resin composition according to claim 1, comprising the amine-based foaming catalyst in an amount of 2 parts by mass or more per 100 parts by mass of the polyol compound.

4. The flame-retardant urethane resin composition according to any one of claims 1 to 3, wherein the amine-based foaming catalyst comprises an aromatic amine represented by the following general formula (1): (In general formula (1), R １ , R ２ , R ３ and R ４ each independently represents an alkyl group or a hydrogen atom.

5. The flame-retardant urethane resin composition according to any one of claims 1 to 4, wherein the amine-based foaming catalyst comprises a tertiary amine represented by the following general formula (2): (In the general formula (2), k is an integer of 0 to 3, R １１ ~R １４ represents a saturated hydrocarbon group having 1 to 2 carbon atoms. Y represents an oxygen atom or -NCH ３ - represents １ , X ２ represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 2 carbon atoms, or an oxygen atom. In the case of an oxygen atom, R １２ , R １３ It bonds to form a morpholine skeleton.)

6. The flame-retardant urethane resin composition according to any one of claims 1 to 5, wherein the amine-based foaming catalyst comprises a guanidine derivative represented by the following general formula (3): (In general formula (3), R ６ , R ７ , R ８ and R ９ each independently represents an alkyl group.

7. The flame-retardant urethane resin composition according to any one of claims 1 to 6, wherein the catalyst is a trimerization catalyst.

8. The flame-retardant urethane resin composition according to any one of claims 1 to 7, wherein the foaming agent contains water, and a polyol composition constituting the flame-retardant urethane resin composition has a moisture content of 0.1 to 3 mass% as measured with a Karl Fischer apparatus.

9. The flame-retardant urethane resin composition according to any one of claims 1 to 8, comprising 50 parts by mass or more of aromatic polyester polyol per 100 parts by mass of the polyol compound.

10. The flame-retardant urethane resin composition according to any one of claims 1 to 9, which is used for spray applications.

11. The flame-retardant urethane resin composition according to any one of claims 1 to 10, wherein the catalyst contains a metal catalyst as a urethanization catalyst.

12. The flame-retardant urethane resin composition according to any one of claims 1 to 11, which is substantially free of inorganic filler.

13. A polyurethane foam formed from the flame-retardant urethane resin composition according to any one of claims 1 to 12.

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