Flame-retardant urethane resin composition

Abstract

To provide a flame-retardant urethane resin composition that can form a polyurethane foam having high fireproofing performance, wherein, the composition can prevent a foam stabilizer from bleeding out on the surface of the formed polyurethane foam and also prevent the polyurethane foam from becoming easily burned.SOLUTION: A flame-retardant urethane resin composition contains a polyol composition containing a polyol compound, a liquid flame retardant, a catalyst, and a foamer, and a polyisocyanate composition containing a polyisocyanate compound. The flame-retardant urethane resin composition is free of a foam stabilizer and has a gel time of 20 seconds or shorter.SELECTED DRAWING: None

Description

Technical Field

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

Background Art

[0002] Polyurethane foams are utilized for heat insulation and dew condensation prevention of various structures such as ceilings, roofs, and wall surfaces of apartment houses, detached houses, commercial buildings, etc. by taking advantage of their excellent heat insulation properties. Polyurethane foams are formed, for example, by spraying a urethane resin composition containing a polyol composition and a polyisocyanate composition onto the surface of each structure and causing it to foam and cure.

[0003] For example, Patent Document 1 describes an invention related to a spray heat insulation material made of rigid polyurethane foam obtained by foaming a compounding liquid containing a polyisocyanate component, a polyol component, water, a catalyst, a foam stabilizer, a flame retardant, and a powder. And it has been shown that the spray heat insulation material is excellent in flame retardancy, dimensional stability, etc.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When a polyurethane foam is formed using a composition containing a foam stabilizer as in Patent Document 1 described above, bleed-out where the foam stabilizer seeps out on the surface of the foam easily occurs, and thus problems such as the object to be used being contaminated or the obtained foam being liable to burn may occur. On the other hand, from the perspective of solving problems such as bleed-out and flammability, it is conceivable to manufacture polyurethane foam without using foam stabilizers. However, it has been found that when foam stabilizers are not used, some of the cells forming the polyurethane foam become more prone to cracking, the cells become coarser, and the thermal insulation performance tends to decrease. Therefore, the present invention aims to provide a flame-retardant urethane resin composition that suppresses the coarseness of cells and yields a polyurethane foam with excellent heat insulation properties when no foam stabilizer is used. [Means for solving the problem]

[0006] As a result of diligent research, the inventors have found that the above problems can be solved by a flame-retardant urethane resin composition containing a polyol composition and a polyisocyanate composition, which does not contain a foam stabilizer and has a gel time below a certain level, and have completed the present invention. That is, the present invention provides the following [1] to [7].

[0007] [1] A flame-retardant urethane resin composition comprising a polyol composition comprising a polyol compound, a liquid flame retardant, a catalyst, and a blowing agent, and a polyisocyanate composition comprising a polyisocyanate compound, wherein the composition does not contain a foam stabilizer and has a gel time of 20 seconds or less. [2] The flame-retardant urethane resin composition described in [1] above, wherein the cream time is 8 seconds or less. [3] The flame-retardant urethane resin composition according to [1] or [2] above, wherein the catalyst contains a metal-based urethane catalyst. [4] The flame-retardant urethane resin composition according to any one of [1] to [3] above, wherein the polyol composition further contains a filler. [5] The flame-retardant urethane resin composition according to any one of [1] to [4] above, wherein the catalyst contains a trimerizing catalyst. [6] The flame-retardant urethane resin composition according to any one of [1] to [5] above, wherein the liquid flame retardant content in the polyol composition is 20 parts by mass or more per 100 parts by mass of the polyol compound. [7] A flame-retardant urethane resin composition according to any of [1] to [6] above, for spray application. [Effects of the Invention]

[0008] Since the present invention is a flame-retardant urethane resin composition that does not use a foam stabilizer, it can suppress the bleed-out of the foam stabilizer onto the surface of the formed polyurethane foam, and can also prevent the polyurethane foam from becoming easily combustible. In addition, it suppresses the coarsening of the cells, resulting in a polyurethane foam with excellent heat insulation properties. [Modes for carrying out the invention]

[0009] The present invention relates to a flame-retardant urethane resin composition comprising a polyol composition containing a polyol compound, a liquid flame retardant, a catalyst, and a blowing agent, and a polyisocyanate composition containing a polyisocyanate compound, wherein the flame-retardant urethane resin composition does not contain a foam stabilizer and has a gel time of 20 seconds or less.

[0010] (Foam stabilizer) The flame-retardant urethane resin composition of the present invention does not contain a foam stabilizer. By not containing a foam stabilizer, it is possible to suppress the bleed-out of the foam stabilizer onto the surface of the polyurethane foam formed when, for example, a silicone-based foam stabilizer is used. Furthermore, by removing the foam stabilizer component, which can be a flammable element, it is possible to prevent the polyurethane foam from becoming easily combustible. Here, "foam stabilizer" refers to a substance that has a foam-stabilizing function in polyurethane foaming, and is generally used in the manufacture of polyurethane foams. Examples of foam stabilizers include silicone-based foam stabilizers and non-silicone-based foam stabilizers. Silicone-based foam stabilizers are compounds having polysiloxane chains and polyoxyalkylene chains, and may have a block-type structure of polysiloxane chains and polyoxyalkylene chains, or a structure in which polyoxyalkylene chains are grafted as side chains onto a main chain of polysiloxane chains. Specific product names of such silicone-based foam stabilizers include, for example, SH-193, SF-2937F, and SF-2945F manufactured by Toray Dow Corning. Non-silicone foam stabilizers refer to foam stabilizers other than silicone foam stabilizers, such as acrylic surfactants. Examples of acrylic surfactants include acrylic polymers having polar groups in their side chains.

[0011] (Geltime) The flame-retardant urethane resin composition of the present invention has a gel time of 20 seconds or less. If the gel time exceeds 20 seconds, the balance between the urethane resin formation rate and the foaming force is disrupted, causing the cells in the polyurethane foam to partially crack and become rough, which tends to reduce the heat insulation properties. From the viewpoint of improving the thermal insulation properties of the formed polyurethane foam, the gel time of the flame-retardant urethane resin composition is preferably 16 seconds or less, more preferably 14 seconds or less, even more preferably 12 seconds or less, and even more preferably 10 seconds or less. The gel time can be adjusted to a desired value by controlling the type and amount of catalyst contained in the polyol composition. The gel time is measured using the cup foaming method. Specifically, it is measured as follows: The liquid temperatures of the polyol composition and polyisocyanate composition constituting the flame-retardant urethane resin composition of the present invention are each adjusted to 10°C. Then, in a room at 23°C, the polyol composition and polyisocyanate composition adjusted to 10°C are poured into a 500 mL cup in a predetermined mixing ratio to obtain a mixture of 60 g in total. Immediately thereafter, the mixture is stirred for 2 seconds at 8000 rpm using a Labodisper (PRIMIX high-speed disperser, Homodisper 2.5 type). The time at which stirring begins is taken as the measurement start time (0 seconds), and the time (in seconds) until the foam begins to string when a rod is inserted into the foam during foaming is measured, and this is defined as the gel time. In addition, if a trimerizing catalyst is included, the stringing of the foam and internal hardening of the foam may occur almost simultaneously. The predetermined mixing ratio mentioned above refers to the mixing ratio of the polyol composition and the polyisocyanate composition when preparing the flame-retardant urethane resin composition of the present invention.

[0012] (Cream time) The flame-retardant urethane resin composition of the present invention preferably has a cream time of 8 seconds or less. When the cream time is 8 seconds or less, the low thermal conductivity foaming agent (e.g., hydrofluoroolefin) contained in the resin composition can be less scattered outside the system and confined in the foam, and it becomes easier to obtain a polyurethane foam with excellent heat insulation properties. From such a viewpoint, the cream time of the flame-retardant urethane resin composition is more preferably 6 seconds or less, still more preferably 5 seconds or less, and even more preferably 4 seconds or less. The cream time can be adjusted to a desired value by adjusting the type and amount of the catalyst contained in the polyol composition. The cream time is a value measured by the cup foaming method. Specifically, it is measured as follows. Adjust the liquid temperatures of the polyol composition and the polyisocyanate composition constituting the flame-retardant urethane resin composition of the present invention to 10 °C respectively. Then, in a room at 23 °C, the polyol composition and the polyisocyanate composition adjusted to 10 °C are put into a 500 mL cup so that the total amount becomes a mixed liquid of 60 g at a predetermined mixing ratio. Thereafter, the mixed liquid is immediately stirred at 8000 rpm for 2 seconds with a Labo Disper (PRIMIX Corporation's high-speed disperser Homodisper 2.5 type). Taking the time when stirring starts as the measurement start time (0 second), measure the time (seconds) until the mixed liquid changes color and the liquid level starts to rise due to foaming, and this is defined as the cream time. Note that the above-mentioned predetermined mixing ratio means the mixing ratio of the polyol composition and the polyisocyanate composition when preparing the flame-retardant urethane resin composition of the present invention.

[0013] [Polyol composition] The polyol composition in the present invention contains a polyol compound, a liquid flame retardant, a catalyst, and a foaming agent. Hereinafter, each component contained in the polyol composition will be described.

[0014] [Polyol compound]< The polyol compound is not particularly limited, and examples thereof include polyether polyol, polyester polyol, and the like. From the viewpoint of improving the flame retardancy of the polyurethane foam, it is preferable that the polyol compound contains a polyester polyol. Also, from the viewpoint of improving the flame retardancy, the use of halogen-containing polyol, phosphorus-containing polyol, and the like is also preferable. From such a viewpoint, among 100 parts by mass of the polyol compound, it is preferable that the polyester polyol is 20 parts by mass or more, more preferably 50 parts by mass or more, still more preferably 80 parts by mass or more, and particularly preferably 100 parts by mass.

[0015] When using two or more types of polyol compounds, as the hydroxyl value of the polyol compound, the average hydroxyl value according to the blending ratio of the two or more types of polyol compounds may be used. For example, when using two types of polyols (d1) and polyol (d2) as the polyol compound, if the hydroxyl value of polyol (d1) is X1, the blending ratio is m1, the hydroxyl value of polyol (d2) is X2, and the blending ratio is m2, the average hydroxyl value is represented by the following formula. The blending ratio is based on mass. Average hydroxyl value (mgKOH / g) = X1 × (m1 / (m1 + m2)) + X2 × (m2 / (m1 + m2)) From the viewpoint of improving the flame retardancy of the polyurethane foam, the average hydroxyl value of the polyol compound used in the present invention is preferably 100 to 500 mgKOH / g, more preferably 150 to 450 mgKOH / g, and still more preferably 200 to 400 mgKOH / g. The hydroxyl value is a value measured in accordance with JIS K1557-1:2007.

[0016] (Polyester polyol) The polyester polyol may be a polyester polyol having an aromatic ring or an aliphatic polyester polyol, but when considering the flame retardancy of the resulting polyurethane foam, it is preferable to use a polyester polyol having an aromatic ring. The polyester polyol having an aromatic ring is preferably a condensate of an aromatic dicarboxylic acid such as o-phthalic acid (phthalic acid), m-phthalic acid (isophthalic acid), p-phthalic acid (terephthalic acid), or naphthalenedicarboxylic acid with a glycol. In particular, from the viewpoint of improving the flame retardancy of the polyurethane foam, the polyol compound preferably contains a phthalic acid-based polyester polyol, which is a condensate of phthalic acid and glycol, and more preferably contains a p-phthalic acid-based polyester polyol, which is a condensate of p-phthalic acid and glycol. While the glycol is not particularly limited, it is preferable to use a low molecular weight aliphatic glycol known as a component of polyester polyols, such as ethylene glycol, propylene glycol, or diethylene glycol.

[0017] The hydroxyl value of the polyester polyol is preferably 100-500 mgKOH / g, more preferably 150-450 mgKOH / g, and even more preferably 200-400 mgKOH / g.

[0018] (Polyether polyol) Polyether polyols are polyoxyalkylene polyols obtained by ring-opening addition polymerization of alkylene oxide to an initiator having two or more active hydrogen atoms. Examples of initiators include aliphatic polyhydric alcohols (e.g., glycols such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, neopentyl glycol, cyclohexylene glycol, and cyclohexanedimethanol; triols such as trimethylolpropane and glycerin; tetrafunctional alcohols such as pentaerythritol; highly functional alcohols such as sucrose and sorbitol); aliphatic amines (e.g., alkylenediamines such as ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, and neopentyldiamine; alkanolamines such as monoethanolamine and diethanolamine); and aromatic amines (e.g., aniline, tolylenediamine, xylylenediamine, diphenylmethanediamine, Mannich condensates, etc.). Of these, polyether polyols produced using an initiator having an aromatic ring are polyether polyols having an aromatic ring. For example, polyether polyols produced using an aromatic amine as an initiator are polyether polyols having an aromatic ring. Among polyether polyols having an aromatic ring, tolylenediamine-based polyether polyols and Mannich-based polyether polyols can be suitably used.

[0019] Tolylenediamine-based polyether polyols are tolylenediamine-based polyether polyols manufactured using tolylenediamine as an initiator. The above-mentioned Mannich-type polyether polyols are obtained using the Mannich reaction and are Mannich condensates having two or more hydroxyl groups in the molecule, or polyether polyols obtained by adding alkylene oxide to such Mannich condensates. More specifically, they are Mannich condensates obtained by the Mannich reaction of at least one of phenol and its alkyl-substituted derivatives, formaldehyde and alkanolamines, or polyether polyols obtained by ring-opening addition polymerization of these compounds with at least one of ethylene oxide and propylene oxide.

[0020] The hydroxyl value of the polyether polyol is preferably 200 to 2000 mg KOH / g, and more preferably 300 to 1000 mg KOH / g.

[0021] <Liquid Flame Retardant> The polyol composition in the present invention preferably contains a liquid flame retardant from the viewpoint of improving the flame retardancy of the resulting polyurethane foam. Among liquid flame retardants, phosphate ester-based flame retardants are particularly preferred. Using a phosphate ester-based flame retardant can improve the flame retardancy of the polyurethane foam, and also allows for appropriate control of the viscosity of the polyol composition even when a filler described later is used. Here, a liquid flame retardant is a flame retardant that is liquid at 23°C.

[0022] Examples of phosphate ester-based flame retardants include monophosphate esters and condensed phosphate esters. Examples of monophosphate esters, though not particularly limited, include trimethyl phosphate, triethyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, and tris(β-chloropropyl) phosphate. Examples of condensed phosphate esters are not particularly limited, but include resorcinol polyphenyl phosphate (trade name CR-733S), bisphenol A polycrezyl phosphate (trade name CR-741), and aromatic condensed phosphate esters (trade name CR747).

[0023] The liquid flame retardant content is preferably 20 parts by mass or more, more preferably 40 parts by mass or more, even more preferably 45 parts by mass or more, preferably 100 parts by mass or less, and more preferably 80 parts by mass or less, per 100 parts by mass of the polyol compound. If the liquid flame retardant content is above these lower limits, the flame retardancy of the polyurethane foam can be improved, and if it is below these upper limits, the mechanical strength of the polyurethane foam can be improved. Furthermore, by including a certain amount or more of the liquid flame retardant, the compatibility when the polyisocyanate composition and the polyol composition are mixed is improved, so it is thought that foam formation stabilization is possible even without the presence of a foam stabilizer.

[0024] <Filler> The polyol composition in the present invention may contain a filler. The filler is included as a solid component in the flame-retardant urethane resin composition and is generally present in granular or powder form. By including a filler, various physical properties such as mechanical strength and flame retardancy can be improved depending on the type of filler. The filler is a component that is solid at room temperature (23°C) and atmospheric pressure (1 atm) and does not dissolve in the flame-retardant urethane resin composition.

[0025] The filler preferably contains a solid flame retardant. Preferred solid flame retardants include boron-based flame retardants, bromine-based flame retardants, phosphate-containing flame retardants, antimony-containing flame retardants, phosphinate-based flame retardants, metal hydroxide-based flame retardants, red phosphorus, and needle-shaped fillers. Among these, red phosphorus and needle-shaped fillers are preferred from the viewpoint of improving the flame retardancy of the polyurethane foam.

[0026] (Boron-based flame retardant) Examples of boron-based flame retardants include alkali metal borates such as lithium borate, sodium borate, potassium borate, and cesium borate; alkaline earth metal borates such as magnesium borate, calcium borate, and barium borate; zirconium borate, zinc borate, aluminum borate, and ammonium borate. Among these, zinc borate is preferred.

[0027] (Bromine-based flame retardant) There are no particular limitations on bromine-based flame retardants as long as they are compounds that contain bromine in their molecular structure. Examples include aromatic brominated compounds. Specific examples of the aromatic brominated compounds include, for example, monomer-based organic bromine compounds such as hexabromobenzene, pentabromotoluene, hexabromobiphenyl, decabromobiphenyl, hexabromocyclodecane, decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, bis(pentabromphenoxy)ethane, ethylenebis(pentabromophenyl), ethylenebis(tetrabromophthalimide), and tetrabromobisphenol A, as well as polycarbonate oligomers produced using brominated bisphenol A as a raw material, and the polycarbonate oligomer and bisphenol Examples include brominated polycarbonates such as copolymers with A, diepoxy compounds produced by the reaction of brominated bisphenol A and epichlorohydrin, monoepoxy compounds obtained by the reaction of brominated phenols and epichlorohydrin, brominated epoxy compounds, poly(brominated benzyl acrylate), brominated polyphenylene ether, brominated bisphenol A, cyanur chloride and brominated phenol condensates, brominated polystyrene such as brominated (polystyrene), poly(brominated styrene), and crosslinked brominated polystyrene, and halogenated brominated compound polymers such as crosslinked or non-crosslinked brominated poly(α-methylstyrene). Among these, ethylenebis(pentabromophenyl), ethylenebis(tetrabromophthalimide), and hexabromobenzene are preferred.

[0028] (Phosphate-containing flame retardant) Examples of phosphate-containing flame retardants include phosphoric acid and metals from groups IA to IVB of the periodic table. At least one metal or compound selected from ammonia, aliphatic amines, and aromatic amines Phosphates, which are salts of substances, can be cited as examples. While there are no specific limitations on phosphates, various types of phosphates can be mentioned, such as monophosphates, pyrophosphates, and polyphosphates. It can be done. Examples of metals from groups IA to IVB of the periodic table include lithium, sodium, calcium, barium, iron(II), iron(III), and aluminum. Examples of aliphatic amines include methylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, and piperazine. Examples of aromatic amines include pyridine, triazine, and melamine. Furthermore, the above-mentioned phosphate-containing flame retardant is treated with a silane coupling agent and coated with melamine resin. Known water-resistance improving treatments, such as [mention specific treatment here], may be added.

[0029] Specific examples of phosphate-containing flame retardants include monophosphates, pyrophosphates, and polyphosphates. The monophosphates are not particularly limited, but examples include ammonium phosphate and dihydrate phosphate. Ammonium salts such as diammonium hydrogen phosphate, monosodium phosphate, Disodium phosphate, trisodium phosphate, monosodium phosphate, dinosodium phosphate Sodium salts such as sodium hypophosphate, monopotassium phosphate, dipotassium phosphate, Tripotassium phosphate, monopotassium phosphate, dipotassium phosphate, potassium hypophosphate, etc. Lithium salts, monolithium phosphate, dilithium phosphate, trilithium phosphate, monolithium phosphate Lithium salts such as dilithium phosphite and lithium hypophosphite, barium dihydrogen phosphate, Barium salts such as barium hydrogen phosphate, tribarium phosphate, and barium hypophosphate, and monophosphate. Magnesium hydrogen, magnesium hydrogen phosphate, trimagnesium phosphate, magnesium hypophosphate Magnesium salts such as calcium dihydrogen phosphate, calcium hydrogen phosphate, triphosphate Calcium, calcium salts such as calcium hypophosphate, zinc phosphate, zinc phosphate, hypo Examples include zinc salts such as zinc phosphate.

[0030] Polyphosphates are not particularly limited, but examples include ammonium polyphosphate, piperazine polyphosphate, melamine polyphosphate, ammonium polyphosphate amide, and aluminum polyphosphate. A single phosphate-containing flame retardant may be used, or two or more types may be used together.

[0031] (Antimony-containing flame retardant) Examples of antimony-containing flame retardants used in the present invention include antimony oxide, antimony salts, and pyroantimony salts. Examples of antimony oxides include antimony trioxide and antimony pentoxide. Examples of antimonate salts include sodium antimonate and potassium antimonate. Examples include pyroantimonate sodium, Examples include potassium pyroantimonate. The antimony-containing flame retardant is preferably antimony oxide. Antimony-containing flame retardants may be used individually or in combination of two or more types. Cut.

[0032] (Phosphinic acid-based flame retardant) Examples of phosphinic acid-based flame retardants include phosphinic acid, dimethylphosphinic acid, methylethylphosphinic acid, methylpropylphosphinic acid, diethylphosphinic acid, dioctylphosphinic acid, phenylphosphinic acid, diethylphenylphosphinic acid, diphenylphosphinic acid, and bis(4-methoxyphenyl)phosphinic acid.

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

[0034] (red phosphorus) The red phosphorus may consist of pure red phosphorus, or it may be red phosphorus mixed with or coated with resin, metal hydroxide, metal oxide, etc.

[0035] (Needle-shaped filler) Examples of needle-shaped fillers include potassium titanate whiskers, aluminum borate whiskers, magnesium-containing whiskers, silicon-containing whiskers, wollastonite, sepiolite, zonolite, elestadite, boehmite, rod-shaped hydroxyapatite, glass fibers, carbon fibers, graphite fibers, metal fibers, slag fibers, gypsum fibers, silica fibers, alumina fibers, silica-alumina fibers, zirconia fibers, boron nitride fibers, boron fibers, stainless steel fibers, and the like. These needle-shaped fillers can be used individually or in combination of two or more types.

[0036] Furthermore, the filler may be an inorganic filler other than the flame retardant mentioned above. Suitable inorganic fillers include alumina, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, ferrites, basic magnesium carbonate, calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, dawsonite, hydrotalcite, calcium sulfate, barium sulfate, calcium silicate, talc, clay, mica, montmorillonite, bentonite, activated clay, imogolite, sericite, glass beads, silica balloon, aluminum nitride, boron nitride, silicon nitride, graphite, carbon balloon, charcoal powder, various metal powders, magnesium sulfate, lead zirconate titanate, molybdenum sulfide, silicon carbide, various magnetic powders, fly ash, etc. The inorganic filler may be used individually or in combination of two or more types.

[0037] The filler content is preferably 10 parts by mass or more, more preferably 25 parts by mass or more, even more preferably 30 parts by mass or more, and preferably 80 parts by mass or less, and more preferably 60 parts by mass or less, per 100 parts by mass of the polyol compound. If the filler content is above these lower limits, it becomes easier for the polyurethane foam to exhibit the function corresponding to the type of filler used. For example, if a solid flame retardant is used as a filler, the flame retardancy of the polyurethane foam tends to improve. If the filler content is below these upper limits, clogging of the spraying equipment is suppressed, and the sprayability can be improved.

[0038] The flame-retardant urethane resin composition may not contain the filler described above. If it does not contain a filler, it is less likely to form precipitates during storage, has excellent handling properties, and can suppress wear on equipment used during use.

[0039] <Foaming agent> Specific examples of blowing agents include, for example, water, low-boiling-point hydrocarbons, chlorinated aliphatic hydrocarbon compounds, fluorine compounds, hydrochlorofluorocarbon compounds, hydrofluorocarbons, ether compounds, and hydrofluoroolefins. Furthermore, blowing agents include organic physical blowing agents such as mixtures of these compounds, and inorganic physical blowing agents such as nitrogen gas, oxygen gas, argon gas, and carbon dioxide gas. Examples of the low-boiling hydrocarbons mentioned above include propane, butane, pentane, hexane, heptane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, and cycloheptane. Examples of the above-mentioned chlorinated aliphatic hydrocarbon compounds include dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, and isopentyl chloride. Examples of the fluorine compounds mentioned above include CHF3, CH2F2, and CH3F. Examples of the above-mentioned hydrochlorofluorocarbon compounds include trichloromonofluoromethane, trichlorotrifluoroethane, and dichloromonofluoroethane (e.g., HCFC141b (1,1-dichloro-1-fluoroethane), HCFC22 (chlorodifluoromethane), HCFC142b (1-chloro-1,1-difluoroethane)). Examples of the above-mentioned hydrofluorocarbons include HFC-245fa (1,1,1,3,3-pentafluoropropane) and HFC-365mfc (1,1,1,3,3-pentafluorobutane). Examples of the ether compounds mentioned above include diisopropyl ether. Examples of the above-mentioned 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-hexafluorobuta-2-ene), and HFO-1224yd(Z).

[0040] Among the above, hydrofluoroolefins and water are preferred as foaming agents, and the use of hydrofluoroolefins and water in combination is more preferable. 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 even more preferably 20 to 50 parts by mass, per 100 parts by mass of the polyol compound.

[0041] The amount of hydrofluoroolefin used as a blowing agent is preferably 3 to 60 parts by mass, more preferably 8 to 57 parts by mass, and even more preferably 19 to 49 parts by mass, per 100 parts by mass of the polyol compound, from the viewpoint of setting the density of the polyurethane foam within a desired range. As the water used as a foaming agent, for example, ion-exchanged water or distilled water can be used as appropriate. The amount of water per 100 parts by mass of the polyol compound is preferably 0.05 to 10 parts by mass, more preferably 0.1 to 3 parts by mass, and even more preferably 0.2 to 2 parts by mass, from the viewpoint of adjusting the isocyanate index to a certain level and adjusting the density of the polyurethane foam to a desired range.

[0042] <Catalyst> The polyol composition contains a catalyst. Examples of catalysts include urethane catalysts and trimerization catalysts. A trimerization catalyst is a catalyst that promotes trimerization, which forms isocyanurate bonds. From the viewpoint of improving the flame retardancy of polyurethane foam and adjusting the gel time of the flame-retardant urethane resin composition to below a certain level, it is preferable that the catalyst contains a trimerization catalyst.

[0043] As trimerization catalysts, nitrogen-containing aromatic compounds such as tris(dimethylaminomethyl)phenol, 2,4-bis(dimethylaminomethyl)phenol, and 2,4,6-tris(dialkylaminoalkyl)hexahydro-S-triazine, alkali metal salts of carboxylic acids such as potassium acetate, potassium 2-ethylhexanoate, and potassium octoate, tertiary ammonium salts such as trimethylammonium salt, triethylammonium salt, and triphenylammonium salt, and quaternary ammonium salts such as tetramethylammonium salt, tetraethylammonium salt, tetraphenylammonium salt, triethylmonomethylammonium salt, and quaternary ammonium carboxylic acid salts can be used. Preferred specific examples of carboxylic acids in the above ammonium carboxylic acid salts are at least one selected from the group consisting of 2-ethylhexanoic acid, 2,2-dimethylpropanoic acid, acetic acid, and formic acid. The trimerization catalyst may be used alone or in combination of two or more, but it is preferable to use two or more in combination. As the trimerizing catalyst, at least one selected from the group consisting of alkali metal carboxylates and quaternary ammonium carboxylates is preferred, and it is preferable to use an alkali metal carboxylate and a quaternary ammonium carboxylate in combination.

[0044] The content of the trimerizing catalyst is preferably 1 to 30 parts by mass, and more preferably 2 to 15 parts by mass, per 100 parts by mass of the polyol compound.

[0045] Furthermore, in the present invention, the catalyst preferably includes a urethane catalyst, and more preferably includes both the trimerizing catalyst and the urethane catalyst described above.

[0046] Urethane catalysts are catalysts that promote the reaction between polyol compounds and polyisocyanate compounds. Specifically, examples of urethane catalysts include amino compounds and metal-based urethane catalysts. Examples of metal-based urethane catalysts include tin compounds, bismuth compounds, and acetylacetone metal salts. Among these, one or more selected from bismuth compounds and tin compounds are preferred from the viewpoint of adjusting the gel time and cream time of the flame-retardant urethane resin composition to a certain level or lower.

[0047] Examples of the aforementioned amino compounds include imidazole compounds such as 1-methylimidazole, 1,2-dimethylimidazole, 1-isobutyl-2-methylimidazole, and imidazole compounds in which the secondary amine functional group in the imidazole ring is substituted with a cyanoethyl group; pentamethyldiethylenetriamine, triethylamine, N-methylmorpholine bis(2-dimethylaminoethyl) ether, bis(2-dimethylaminoethyl) ether, N,N,N',N”,N”-pentamethyldiethylenetriamine, N,N,N'-trimethylaminoethyl-ethanolamine, bis(2-dimethylaminoethyl) ether, N-methyl-N',N'-dimethylaminoethylpiperazine, N,N-dimethylcyclohexylamine, diazabicycloundecene, triethylenediamine, tetramethylethylenediamine, tetramethylhexamethylenediamine, trimethylaminoethylpiperazine, tripropylamine, N,N,N',N'-tetramethylguanidine, and their acid block derivatives. Among amino compounds, imidazole compounds are preferred from the viewpoint of storage stability.

[0048] Examples of tin compounds include stannous octoate, dibutyltin diacetate, and dibutyltin dilaurate. Examples of bismuth compounds include bismuth neodecanoate and bismuth octoate. Examples of acetylacetone metal salts include aluminum acetylacetone, iron acetylacetone, copper acetylacetone, zinc acetylacetone, beryllium acetylacetone, chromium acetylacetone, indium acetylacetone, manganese acetylacetone, molybdenum acetylacetone, titanium acetylacetone, cobalt acetylacetone, vanadium acetylacetone, and zirconium acetylacetone. In the present invention, the catalyst preferably contains the bismuth compound described above, from the viewpoint of keeping the gel time and cream time of the flame-retardant urethane resin composition below a certain level.

[0049] The catalyst preferably contains a metal-based urethane catalyst, and the content of the metal-based urethane catalyst is preferably 0.5 to 15 parts by mass, more preferably 1 to 13 parts by mass, and even more preferably 1.5 to 10 parts by mass, per 100 parts by mass of the polyol compound.

[0050] Furthermore, from the viewpoint of keeping the gel time below a certain level, it is preferable to use a metal-based urethane catalyst and an amino compound in combination as the urethane catalyst, and among these, the combination of a bismuth compound and an imidazole compound is more preferable. When a metal-based urethane catalyst and an amino compound are used in combination, the mass ratio of the amino compound to the metal-based urethane catalyst (mass of amino compound / mass of metal-based urethane catalyst) is preferably 0.1 to 10, more preferably 0.5 to 8, and even more preferably 1 to 5.

[0051] There are no particular limitations on the content of the urethane catalyst, but it is preferably 1 to 30 parts by mass, and more preferably 5 to 25 parts by mass, per 100 parts by mass of the polyol compound.

[0052] Furthermore, the total amount of catalyst is preferably 2 to 60 parts by mass, and more preferably 7 to 40 parts by mass, per 100 parts by mass of the polyol compound.

[0053] <Polyisocyanate compounds> As the polyisocyanate compound included in the polyisocyanate composition of the present invention, various polyisocyanate compounds such as aromatic, alicyclic, and aliphatic compounds having two or more isocyanate groups can be used. Preferably, liquid diphenylmethane diisocyanate (MDI) is used due to its ease of handling, rapid reaction, excellent physical properties of the resulting polyurethane foam, and low cost. Examples of liquid MDI include crude MDI (also called polymeric MDI). Specific commercially available liquid MDIs include "44V-10" and "44V-20" (manufactured by Sumika Covestro Urethane Co., Ltd.) and "Millionate MR-200" (Nippon Polyurethane Industry Co., Ltd.). Alternatively, uretonimine-containing MDI (for example, "Millionate MTL": manufactured by Nippon Polyurethane Industry Co., Ltd. as a commercially available product) may also be used. Furthermore, a treatment in which some of the isocyanate active groups in the isopolycyanate compound are reacted with a hydroxyl group-containing compound to increase its affinity with polyols may be used. In addition to liquid MDI, other polyisocyanate compounds may be used in combination, and any polyisocyanate compound known in the field of polyurethanes can be used without limitation. Furthermore, the polyisocyanate composition may consist solely of a polyisocyanate compound.

[0054] The mixing ratio of the polyol composition and the polyisocyanate composition of the present invention is preferably adjusted so that the isocyanate index of the flame-retardant urethane resin composition is as follows. When the flame-retardant urethane resin composition is used for spraying, the volume ratio of the polyisocyanate composition to the polyol composition (polyisocyanate composition / polyol composition) is not particularly limited, but is preferably 0.8 to 1.2, and more preferably 0.9 to 1.1.

[0055] The isocyanate index of the flame-retardant urethane resin composition is preferably 150 to 600, and more preferably 200 to 500. If the isocyanate index is above these lower limits, it becomes easier to obtain a highly flame-retardant polyurethane foam, and if the isocyanate index is below these upper limits, good foaming properties can be achieved during foam formation. The isocyanate index (INDEX) is calculated by dividing the number of moles of isocyanate groups in a polyisocyanate by the total number of moles of hydroxyl groups in a polyol and the active hydrogen groups of water used as a blowing agent, and then multiplying the result by 100. The method is as follows:

[0056] INDEX = Equivalents of isocyanate ÷ (Equivalents of polyol + Equivalents of water) × 100 Here, Equivalent weight of isocyanate = Number of polyisocyanates used × NCO content (%) × 100 / Molecular weight of NCO The equivalent weight of the polyol = OHV × the amount of polyol used ÷ the molecular weight of KOH, where OHV is the hydroxyl value of the polyol (mgKOH / g). Equivalent amount of water = Number of parts of water used × Number of OH groups in water / Molecular weight of water In the above formula, the unit of the number of parts used is weight (g), the molecular weight of the NCO group is 42, the NCO content is the proportion of NCO groups in the polyisocyanate compound expressed in mass%, and for the sake of unit conversion in the above formula, the molecular weight of KOH is assumed to be 56100, the molecular weight of water is assumed to be 18, and the number of OH groups in water is assumed to be 2.

[0057] The flame-retardant urethane resin composition may also contain, to the extent that it does not impede the effects of the present invention, other additives such as antioxidants (phenol-based, amine-based, sulfur-based, etc.), heat stabilizers, light stabilizers, metal damage inhibitors, antistatic agents, crosslinking agents, lubricants, softeners, pigments, dyes, tackifying resins, etc.

[0058] The flame-retardant urethane resin composition of the present invention hardens through a reaction between a polyol compound and a polyisocyanate compound, and therefore its viscosity changes over time. For this reason, before using the composition, it is preferable to divide it into two or more parts to prevent the composition from reacting and hardening. When using the composition, it is preferable to mix the two or more parts that have been divided. When dividing a flame-retardant urethane resin composition into two or more parts, the components should be divided in such a way that curing does not begin with each component of the divided flame-retardant urethane resin composition alone, but only after the components of the flame-retardant urethane resin composition are mixed. Typically, a flame-retardant urethane resin composition is divided into a polyol composition containing a polyol compound, a flame retardant, a catalyst, and a blowing agent, and a polyisocyanate composition containing a polyisocyanate compound. The polyol composition and the polyisocyanate composition are then mixed to prepare the flame-retardant urethane resin composition.

[0059] [Polyurethane foam] The polyurethane foam of the present invention is formed from the above-described flame-retardant urethane resin composition, and more specifically, is obtained by foaming and curing the flame-retardant urethane resin composition.

[0060] (density) The density of polyurethane foam is not particularly limited, but is typically between 20 and 200 kg / m³. 3 It is preferable that the density be within this range. 3 By doing the following, the polyurethane foam becomes lighter, improving its ease of application to structures. Also, 20 kg / m 3 By doing so, the desired flame retardancy is more easily achieved. From these perspectives, the density of the polyurethane foam should be 20-100 kg / m³. 3 It is more preferable that the range be 23-80 kg / m 3 It is even more preferable that the density be within this range. The density of the polyurethane foam can be measured in accordance with JIS K7222.

[0061] The polyurethane foam of the present invention can be obtained by mixing a polyol composition and a polyisocyanate composition to prepare a flame-retardant urethane resin composition, and then foaming it. The mixing of each component and foaming can be carried out by known methods. For example, it can be obtained using known equipment such as a high-pressure foamer, a low-pressure foamer, a spray foamer, or a hand mixer.

[0062] (Application) The flame-retardant urethane resin composition of the present invention and the polyurethane foam obtained by foaming the composition are not particularly limited in their uses, but they can be used to fill cavities in structures such as buildings, furniture, automobiles, trains, and ships, or to spray onto such structures. In particular, it is preferable to use them for spraying onto structures, that is, as a flame-retardant urethane resin composition for spraying. Spraying can be carried out using a spraying device (e.g., GRACO A-25) and a spray gun (e.g., Gasmar D-gun). Spraying can be carried out by adjusting the temperature of the polyol composition and polyisocyanate composition in separate containers within the spraying device, mixing them by collision at the tip of the spray gun, and atomizing the mixture with air pressure. The volume ratio of the polyisocyanate composition to the polyol composition in the mixture (polyisocyanate composition / polyol composition) is not particularly limited, but is usually 0.8 to 1.2, and more generally 0.9 to 1.1. The spraying equipment and spray gun are well-known and commercially available products can be used. Furthermore, the stock solution temperature and pressure settings can be the same as those for general polyurethane foam spraying. [Examples]

[0063] The present invention will be described in more detail by reference to examples, but the present invention is not limited in any way by these examples.

[0064] The details of each component used in each example and comparative example are as follows. <Polyol compounds> • p-phthalate-based polyester polyol (manufactured by Kawasaki Chemical Co., Ltd., product name: RFK-505, hydroxyl value = 250 mg KOH / g)

[0065] <Catalyst> (i) Trimerization catalyst: Potassium 2-ethylhexanoate (manufactured by Evonik Japan, product name: DABCO K-15), concentration 70-80% by mass (ii) Trimerization catalyst: Quaternary ammonium carboxylic acid salt (manufactured by Evonik Japan, product name: DABCO TMR-7), concentration 45-55% by mass (iii) Urethane catalyst: 1,2-dimethylimidazole (manufactured by Kao Corporation, product name: Kaolizer No. 390), concentration 65-75% by mass (iv) Urethane catalyst: Bismuth 2-ethylhexanoate (manufactured by Nitto Chemical Co., Ltd., product name: BI28), concentration 81-90% by mass (v) Urethane catalyst: N,N,N',N'-tetramethylguanidine (manufactured by Evonik Japan, product name: POLYCAT 201), concentration 60%

[0066] <Liquid Flame Retardant> • Phosphate ester-based flame retardant: Tris(β-chloropropyl) phosphate (manufactured by Daihachi Chemical Co., Ltd., product name: TMCPP) <Filler> • Filler: Red phosphorus (Phosphorus Chemical Industry, product name: Nova Excel 140), solid flame retardant • Filler: Wollastonite (SiO2·CaO) (manufactured by Kinsei Matec Co., Ltd., product name: SH-1250), solid flame retardant

[0067] <Foaming agent> ·water • HFO-1233zd <Hydrofluoroolefin> (Honeywell, product name: Solstice LBA) • HFO-1336mzz(Z) (Manufactured by Chemours, product name: OPTEON1100)

[0068] <Polyisocyanate compounds> • MDI (manufactured by Sumika Covestro Urethane Co., Ltd., product name: 44V-20)

[0069] <Foam stabilizer> • Silicone-based foam stabilizer (manufactured by Toray Dow Corning, product name: SF-2945F)

[0070] The flame-retardant urethane resin compositions of each example and comparative example, and the polyurethane foams formed from these compositions, were evaluated as follows.

[0071] [Geltime] The liquid temperatures of the polyol composition and the polyisocyanate composition consisting of polyisocyanate compounds (MDI) listed in Table 1 were adjusted to 10°C. Then, in a room at 23°C, the polyol composition and polyisocyanate composition adjusted to 10°C were added to a 500 mL cup in the mixing ratio shown in the table, resulting in a total volume of 60 g. The mixture was then immediately stirred at 8000 rpm for 2 seconds using a Labodisper (PRIMIX high-speed disperser, Homodisper 2.5 type). The time at which stirring began was defined as the measurement start time (0 seconds), and the time (in seconds) until the foam began to string when a rod was inserted into the foam during foaming was measured and defined as the gel time.

[0072] [Cream Time] The liquid temperatures of the polyol composition and the polyisocyanate composition consisting of polyisocyanate compounds (MDI) listed in Table 1 were adjusted to 10°C. Then, in a room at 23°C, the polyol composition and polyisocyanate composition adjusted to 10°C were added to a 500 mL cup in the mixing ratio shown in the table, resulting in a total volume of 60 g. The mixture was then immediately stirred at 8000 rpm for 2 seconds using a Labodisper (PRIMIX high-speed disperser, Homodisper 2.5 type). The time at which stirring began was defined as the measurement start time (0 seconds), and the time (seconds) until the mixture changed color and the liquid level began to rise due to foaming was measured and defined as the cream time.

[0073] [Observation of the cell state of polyurethane foam] The polyurethane foams produced in each example and comparative example were visually observed and evaluated as follows: "○" indicated that the cell structure was fine and there were no noticeable bubbles, while "×" indicated that the cells were cracked or otherwise in a rough state.

[0074] [Thermal conductivity] The polyurethane foams prepared in Example 7 and Comparative Examples 1 and 4 were cut to a size of 200 mm in length, 200 mm in width, and 25 mm in thickness, and used as samples for thermal conductivity measurement. The thermal conductivity was measured in the thickness direction of the sample using the heat flow meter method with the "HC-074" manufactured by Eikoh.

[0075] [External contamination (bleed)] Lines were drawn on the surface of the polyurethane foam prepared in each example and comparative example using a marker (ZEBRA "Mackie Extra Fine" oil-based black marker). Those that did not repel the marker ink were rated "○", and those that did repel it were rated "×". Note that if the marker ink was repelled, it meant that foam stabilizers or other substances had bled out from the surface of the polyurethane foam, indicating that it was likely to contaminate the object it was intended to be used on.

[0076] [Flammable] The polyurethane foam prepared in each example and comparative example was cut into pieces measuring 10 cm in length, 10 cm in width, and 3.25 cm in thickness (including 12.5 mm of gypsum board) to prepare samples for cone calorimeter testing. These test samples were subjected to a radiant thermal intensity of 50 kW / m² in accordance with the ISO-5660 test method. 2 When heated, the burning time after ignition of the sample was measured. Samples with a burning time of 100 seconds or less were evaluated as "○", and those with a burning time exceeding 100 seconds were evaluated as "×".

[0077] [Examples 1-7, Comparative Examples 1-4] Polyol compositions were prepared according to the formulations shown in Table 1. Furthermore, a polyisocyanate composition consisting of MDI was prepared. Each composition was introduced into a spraying apparatus (GRACO: A-25). After adjusting the temperature within the apparatus, a flame-retardant urethane resin composition consisting of a mixture of the polyol composition and the polyisocyanate composition was sprayed onto a 12.5 mm thick gypsum board using a spray gun (GRACO: AP gun) to form a polyurethane foam. The polyurethane foam thus formed was evaluated for the "cell state observation of the polyurethane foam" and "thermal conductivity" as described above, and the results are shown in Table 1.

[0078] A polyol composition obtained using the formulation shown in Table 1 and a polyisocyanate composition consisting of a polyisocyanate compound were stirred for 2 seconds at a liquid temperature of 10°C and 8000 rpm to obtain a flame-retardant urethane resin composition, totaling 200 g. This flame-retardant urethane resin composition was then sprayed into a box measuring 180 mm x 180 mm and 100 mm in depth to form a polyurethane foam. The polyurethane foam thus formed was evaluated for "external contamination (bleed)" as described above. For the evaluation of "flammability," a polyurethane foam was used as the sample, formed by scattering a flame-retardant urethane resin composition inside a box with a 12.5 mm thick gypsum board set as a base at the bottom.

[0079] [Table 1]

[0080] Note that the mass parts of each catalyst represent the mass parts of the product.

[0081] In each example, the flame-retardant urethane resin composition did not contain a foam stabilizer, resulting in polyurethane foams with less surface bleeding and greater resistance to combustion. Furthermore, despite the absence of a foam stabilizer, the cellular structure was good, and the foams exhibited low thermal conductivity and excellent heat insulation properties. On the other hand, the flame-retardant urethane resin composition of Comparative Example 1 contained a foam stabilizer, resulting in a large amount of surface bleeding in the resulting polyurethane foam, which was also highly flammable. Although the flame-retardant urethane resin compositions of Comparative Examples 2 to 4 did not contain a foam stabilizer, their gel time was large, resulting in a coarse cell structure, and consequently, high thermal conductivity and poor heat insulation.

Claims

1. A flame-retardant urethane resin composition for spraying, comprising a polyol composition containing a polyol compound, a filler, a liquid flame retardant, a catalyst, and a blowing agent, and a polyisocyanate composition containing a polyisocyanate compound, The polyol compound includes a polyester polyol having an aromatic ring, The filler contains red phosphorus, The liquid flame retardant includes a phosphate ester-based flame retardant. The catalyst includes a urethane catalyst and a trimerizing catalyst. The urethane catalyst comprises one or more metal-based urethane catalysts selected from bismuth compounds and tin compounds, and an imidazole compound. The trimerizing catalyst comprises one or more selected from the group consisting of alkali metal carboxylic acid salts and quaternary ammonium carboxylic acid salts. The blowing agent comprises a hydrofluoroolefin, A flame-retardant urethane resin composition for spraying, which does not contain a foam stabilizer and has a gel time of 20 seconds or less, and is used to form thermal insulation material by spraying it onto the surface of a structure using a spraying device and spray gun.

2. A flame-retardant urethane resin composition for spraying, used to form an insulating material by spraying it onto the surface of a structure using the spraying apparatus and spray gun described in claim 1, wherein the cream time is 8 seconds or less.

3. A flame-retardant urethane resin composition for spraying, used to form a heat insulating material by spraying it onto the surface of a structure using the spraying apparatus and spray gun according to claim 1 or 2, wherein the content of the filler is 10 to 80 parts by mass per 100 parts by mass of the polyol compound.

4. A flame-retardant urethane resin composition for spraying, used to form an insulating material by spraying it onto the surface of a structure using a spraying apparatus and spray gun according to any one of claims 1 to 3, wherein the liquid flame retardant content is 20 parts by mass or more per 100 parts by mass of the polyol compound.

5. A flame-retardant urethane resin composition for spraying, used to form an insulating material by spraying it onto the surface of a structure using a spraying apparatus and spray gun according to any one of claims 1 to 4, wherein the blowing agent contains hydrofluoroolefin and water, the hydrofluoroolefin content is 3 to 60 parts by mass per 100 parts by mass of the polyol compound, and the water content is 0.05 to 10 parts by mass per 100 parts by mass of the polyol compound.

6. A flame-retardant urethane resin composition for spraying onto the surface of a structure to form an insulating material, using a spraying apparatus and spray gun according to any one of claims 1 to 5, wherein the trimerizing catalyst contains an alkali metal carboxylic acid salt and a quaternary ammonium carboxylic acid salt.

7. A flame-retardant urethane resin composition for spraying onto the surface of a structure to form an insulating material, using a spraying apparatus and spray gun according to any one of claims 1 to 6, wherein the content of the trimerizing catalyst is 1 to 30 parts by mass per 100 parts by mass of the polyol compound, and the content of the urethane catalyst is 1 to 30 parts by mass per 100 parts by mass of the polyol compound.

8. A polyurethane foam formed from a flame-retardant urethane resin composition for spraying, which is used to form an insulating material by spraying it onto the surface of a structure using a spraying apparatus and spray gun according to any one of claims 1 to 7.

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