Polyurethane foam composition, battery, polyurethane foam joint material

Abstract

The present invention provides a urethane foam composition that exhibits excellent deformability, thermal expansion properties, shape retention after thermal expansion, and adhesion to the substrate after thermal expansion. [Solution] According to the present invention, a urethane foam composition is provided which contains more than 100 parts by mass and up to 2000 parts by mass of a phosphoric acid-based inorganic compound per 100 parts by mass of a urethane compound, and the content of a thermally expandable layered inorganic compound is less than 10 parts by mass.

Description

Technical Field

[0001] The present invention relates to a urethane foam composition, a battery, and a urethane foam joint material. The urethane foam composition relates to, for example, one used for a urethane foam joint material. The urethane foam joint material is used, for example, for part or all of the gaps of through-holes provided in a fire compartment, or between a seismic isolation device and a fire-resistant panel of a building or at the end of the fire-resistant panel. Further, the urethane foam composition relates to one used for a battery.

Background Art

[0002] Fireproof expansion materials have been used as joint materials between cables such as power cables and communication cables passing through a fire compartment and pipes such as air-conditioning equipment and a fireproof wall. The fireproof expansion material expands by heating during a fire to form an expansion layer, thereby closing the gap of the through-hole in the fire compartment to prevent the spread of fire. Therefore, in the fireproof joint material made of a fireproof expansion material, particularly after the formation of the expansion layer, it is required that the expansion layer does not easily collapse due to heat and can maintain a predetermined shape for as long as possible.

[0003] As a composition having fire resistance, a curing composition for a sealing material using a urethane prepolymer has been disclosed (Patent Document 1). This has excellent rubber elasticity even when heated up to about 400°C and is characterized by smoothly following the dimensional changes of the sealing part occurring during a fire, but it burns at higher temperatures and a gap is formed due to a decrease in volume.

[0004] As a fireproof expansion material excellent in elasticity and flexibility, a method for producing a polyurethane imparted with fire resistance has been disclosed (Patent Document 2). This is characterized by blending expandable graphite as a flame retardant with a polyol and a polyisocyanate and using powdered casein as a shape stabilizer.

[0005] Furthermore, a fire-resistant joint material consisting of flexible polyurethane foam, epoxy resin, and thermally expandable graphite has been disclosed (Patent Document 3).

[0006] In recent years, thermally expandable fire-resistant materials have also come to be used in battery components. Various battery cells, such as lithium-ion batteries, can ignite and produce smoke at high temperatures. In order to minimize damage in the event of a fire originating from a battery cell, thermally expandable fire-resistant materials are sometimes used around the battery cell. For example, Patent Document 4 provides an example of a thermally expandable fire-resistant sheet containing a matrix resin and thermally expandable graphite, with at least 5% by mass of the thermally expandable graphite, and specifying the relationship between the thickness of the thermally expandable fire-resistant sheet and the average aspect ratio of the thermally expandable graphite. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2023-001074 [Patent Document 2] Special table flat 03-504738 [Patent Document 3] Japanese Patent Publication No. 2006-070155 [Patent Document 4] Japanese Patent Publication No. 2018-115319 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The thermally expandable graphite described in Patent Document 2 is obtained by treating powders of natural graphite, pyrolysis graphite, etc., with inorganic acids such as sulfuric acid and nitric acid, and strong oxidizing agents such as concentrated nitric acid and permanganate, and is a flattened crystalline compound that maintains a graphite layered structure. When exposed to temperatures of about 200°C or higher, it expands thermally in an accordion shape, for example, by more than 100 times. There is a trade-off relationship between this thermal expandability and the ability to maintain its shape, and it has not been possible to achieve both properties simultaneously.

[0009] Similarly, the heat-expandable fire-resistant sheets described in Patent Documents 3 and 4 also failed to achieve both heat expansion and shape retention. Furthermore, the residue after thermal expansion had poor adhesion to metal or resin substrates such as firewalls and batteries, and those installed vertically or upside down were prone to falling off due to the heat, wind, or deformation of the adherend during a fire, which was a problem.

[0010] Therefore, the present invention provides a urethane foam composition that exhibits excellent deformability, thermal expandability, shape retention after thermal expansion, and adhesion to a substrate after thermal expansion. [Means for solving the problem]

[0011] As a result of diligent research to solve the above problems, the inventors of the present invention have found that the above problems can be solved by using a specific compound composition, and have completed the present invention.

[0012] In other words, the present invention provides the following invention. [1] A urethane foam composition comprising more than 100 parts by mass and up to 2000 parts by mass of a phosphoric acid-based inorganic compound per 100 parts by mass of a urethane compound, wherein the content of a thermally expandable layered inorganic compound is less than 10 parts by mass. [2] The urethane foam composition according to [1], wherein the urethane compound includes a urethane prepolymer or a structure derived from a urethane prepolymer. [3] The urethane foam composition according to [1], wherein the phosphate-based inorganic compound comprises at least one selected from aluminum hydrogen phosphite and aluminum disphosphate. [4] The urethane foam composition according to [1], wherein the content of the phosphoric acid-based inorganic compound is 150 to 1600 parts by mass. [5] The urethane foam composition according to [1], wherein the content of the phosphoric acid-based inorganic compound is 200 to 1200 parts by mass. [6] The urethane foam composition according to [1], wherein the content of the thermally expandable layered inorganic compound is less than 3 parts by mass. [7] The urethane foam composition according to [1], wherein the content of the thermally expandable layered inorganic compound is 0 parts by mass. [8] The urethane foam composition according to any one of [1] to [7], which is used for a battery. [9] A battery comprising the urethane foam composition according to [8].

[10] A fireproof joint material using the urethane foam composition according to any one of [1] to [7]. [Advantages of the Invention]

[0013] According to the present invention, it is possible to provide a urethane foam composition excellent in deformability, thermal expandability, shape retention after thermal expansion, and adhesion to a base material after thermal expansion. Such a urethane foam composition can be used as a fireproof joint material or a refractory material for a battery. [Brief Description of the Drawings]

[0014] [Figure 1] FIG. 1A is a schematic view showing a state of attaching a paste-like composition to the surface of a cylindrical battery cell. FIG. 1B is a schematic view showing a state where the paste-like composition is attached to the surface of the cylindrical battery cell. [Figure 2] FIG. 2 is a diagram for explaining a method of cutting out a sample piece from the urethane foam composition in an example. [Figure 3] FIG. 3 is a diagram for explaining a test method for adhesion after thermal expansion. [Embodiments for Carrying Out the Invention]

[0015] Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as "the present embodiment") will be described in detail, but the present invention is not limited thereto, and various modifications are possible without departing from the gist thereof.

[0016] The present invention relates to a urethane foam composition which contains more than 100 parts by mass and 2000 parts by mass or less of a phosphoric acid-based inorganic compound with respect to 100 parts by mass of a urethane compound, and the content of the thermally expandable layered inorganic compound is less than 10 parts by mass. Hereinafter, each component will be described.

[0017] 1. Urethane foam composition The urethane foam composition according to an embodiment of the present invention is a foam composed of a composition containing more than 100 parts by mass and 2000 parts by mass or less of a phosphoric acid-based inorganic compound with respect to 100 parts by mass of a urethane compound. Such a urethane foam composition is excellent in deformability, thermal expansibility, shape retention after thermal expansion, and adhesion to a base material after thermal expansion, and can be used as a fireproof joint material or a refractory material for batteries.

[0018] <Urethane compound> The urethane compound is a compound having a urethane bond, preferably polyurethane. The urethane compound preferably forms a urethane foam (foam) together with additives such as a phosphoric acid-based inorganic compound. The urethane foam can be obtained, for example, by reacting a urethane raw material with a foaming agent. For example, carbon dioxide is generated by the reaction of the isocyanate group of the urethane raw material with water, and as a result of foaming by this, a urethane foam is obtained. The urethane foam composition preferably has a foaming ratio of 2 to 20 times and a density of 120 to 500 kg / m 3 is.

[0019] The urethane raw material contains an isocyanate compound. The urethane compound preferably contains a urethane prepolymer or a structure derived from a urethane prepolymer. The structure derived from a urethane prepolymer may be, for example, a structure in which a urethane prepolymer reacts with other components (polyol, foaming agent, etc.) to form at least a part of polyurethane when forming a urethane foam.

[0020] The urethane foam composition may contain 4 to 50% by mass of a urethane compound per 100% by mass of the urethane foam composition, preferably 6 to 40% by mass, and more preferably 10 to 33% by mass. When this range is met, the urethane foam composition can have appropriate hardness and thermal expansion properties. Specifically, the content of the urethane compound may be, for example, 4, 5, 6, 10, 15, 20, 25, 30, 33, 35, 40, 45, or 50% by mass, and may be within the range of any two of the values ​​exemplified here.

[0021] <Isocyanate compounds> An isocyanate compound is, for example, a compound having two or more isocyanate groups. The isocyanate compound includes one or more selected from the group consisting of polyisocyanates having two or more isocyanate groups, and polymers obtained by reacting a polyol with an excess of polyisocyanate, which have isocyanate groups at their molecular ends (urethane prepolymers).

[0022] The urethane raw material may contain a polyol in addition to the isocyanate compound. For example, the urethane raw material may contain polyisocyanate and a polyol. If the urethane raw material contains multiple components, they may be mixed beforehand, or some or all of the components may be mixed in the reaction system.

[0023] When polyisocyanate and polyol are added as urethane raw materials, for example, 10 to 200 parts by mass of polyol can be added per 100 parts by mass of polyisocyanate, and it is preferable to add 50 to 150 parts by mass of polyol. Specifically, the amount of polyol to be added is, for example, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, or 200 parts by mass per 100 parts by mass of polyisocyanate, and may be within the range of any two of the values ​​exemplified here.

[0024] <Urethane prepolymer> Urethane prepolymers are polymers obtained by reacting polyols with excess polyisocyanates, and are compounds that have isocyanate groups at the molecular ends.

[0025] Examples of polyisocyanates include aromatic isocyanates, alicyclic isocyanates, and aliphatic isocyanates.

[0026] Examples of aromatic isocyanates include phenylenediisocyanate, tolylenediisocyanate, xylylenediisocyanate, diphenylmethanediisocyanate, dimethyldiphenylmethanediisocyanate, triphenylmethanetriisocyanate, naphthalenediisocyanate, and polymethylenepolyphenylpolyisocyanate.

[0027] Examples of alicyclic isocyanates include cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and dimethyldicyclohexylmethane diisocyanate.

[0028] Examples of aliphatic isocyanates include methylene diisocyanate, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, and hexamethylene diisocyanate.

[0029] One or more types of polyisocyanates may be used.

[0030] Examples of polyols include polylactone polyols, polycarbonate polyols, aromatic polyols, alicyclic polyols, aliphatic polyols, polyester polyols, polymer polyols, and polyether polyols.

[0031] Examples of polylactone polyols include polypropiolactone glycol, polycaprolactone glycol, and polyvalerolactone glycol.

[0032] Examples of polycarbonate polyols include polyols obtained by the de-alcoholization reaction of hydroxyl group-containing compounds such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, octanediol, and nonanediol with diethylene carbonate, dipropylene carbonate, etc.

[0033] Examples of aromatic polyols include bisphenol A, bisphenol F, phenol novolac, and cresol novolac.

[0034] Examples of alicyclic polyols include cyclohexanediol, methylcyclohexanediol, isophoronediol, dicyclohexylmethanediol, and dimethyldicyclohexylmethanediol.

[0035] Examples of aliphatic polyols include ethylene glycol, propylene glycol, butanediol, pentanediol, and hexanediol.

[0036] Examples of polyester polyols include polymers obtained by dehydration condensation of a polybasic acid and a polyhydric alcohol, polymers obtained by ring-opening polymerization of lactones such as ε-caprolactone and α-methyl-ε-caprolactone, and condensates of hydroxycarboxylic acids and the above-mentioned polyhydric alcohols.

[0037] Examples of polymer polyols include polymers obtained by graft polymerization of ethylenically unsaturated compounds such as acrylonitrile, styrene, methyl acrylate, and methacrylate onto aromatic polyols, alicyclic polyols, aliphatic polyols, polyester polyols, etc., polybutadiene polyols, modified polyols of polyhydric alcohols, or hydrogenated versions thereof.

[0038] Examples of polyether polyols include polymers obtained by ring-opening polymerization of at least one alkylene oxide such as ethylene oxide, propylene oxide, or tetrahydrofuran in the presence of at least one low molecular weight active hydrogen compound having two or more active hydrogen atoms.

[0039] One or more types of polyols can be used.

[0040] <Foaming agent> A foaming agent promotes foaming. Examples of foaming agents include hydrofluoroolefins with 3 or 4 carbon atoms, such as trans-1-chloro-3,3,3-trifluoropropene, and water. Of these, water is preferred as it readily dissolves phosphorylated inorganic compounds.

[0041] <Phosphate-based inorganic compounds> Phosphate-based inorganic compounds are used to impart shape retention properties to urethane foam compositions that undergo significant thermal expansion when exposed to high temperatures such as 600°C, and that maintain their expanded form. Phosphate-based inorganic compounds include at least one of the following: phosphate compounds, phosphite compounds, hypophosphite compounds, metaphosphate compounds, pyrophosphate compounds, and polyphosphate compounds.

[0042] Examples of phosphate compounds include monoaluminum phosphate, monosodium phosphate, monopotassium phosphate, monocalcium phosphate, monozinc phosphate, dialuminum phosphate, disodium phosphate, dipotassium phosphate, dicalcium phosphate, dizinc phosphate, trialuminum phosphate, trisodium phosphate, tripotassium phosphate, tricalcium phosphate, trizinc phosphate, trimagnesium phosphate, monoammonium phosphate, diammonium phosphate, tricalcium phosphate, and aluminum phosphate.

[0043] Examples of phosphite compounds include aluminum phosphite, aluminum hydrogen phosphite, sodium phosphite, potassium phosphite, calcium phosphite, and zinc phosphite.

[0044] Examples of hypophosphite compounds include aluminum hypophosphite, sodium hypophosphite, potassium hypophosphite, calcium hypophosphite, and zinc hypophosphite.

[0045] Examples of metaphosphate compounds include aluminum metaphosphate, sodium metaphosphate, potassium metaphosphate, calcium metaphosphate, zinc metaphosphate, and sodium hexametaphosphate.

[0046] Examples of pyrophosphate compounds include sodium pyrophosphate.

[0047] Examples of polyphosphate compounds include ammonium polyphosphate, melamine-modified ammonium polyphosphate, sodium tripolyphosphate, sodium pentapolyphosphate, sodium tetrapolyphosphate, and potassium tripolyphosphate.

[0048] The content of the phosphoric acid-based inorganic compound is more than 100 parts by mass and 2000 parts by mass or less per 100 parts by mass of the urethane compound, preferably 150 to 1600 parts by mass, and more preferably 200 to 1200 parts by mass. If the content of the phosphoric acid-based inorganic compound is 100 parts by mass or less, the thermal expansion properties will be poor. If the content of the phosphoric acid-based inorganic compound exceeds 2000 parts by mass, the hardness will become too high, and the deformability due to the flexibility of the urethane foam will be impaired. The content of the phosphoric acid-based inorganic compound is, specifically, 101, 102, 150, 175, 200, 250, 300, 400, 500, 600, 700, 800, 850, 900, 950, 1000, 1100, 1200, 1300, 1400, 1450, 1500, 1600, 1700, 1800, 1900, and 2000 parts by mass per 100 parts by mass of the urethane compound, and may be within the range of any two of the values ​​exemplified here.

[0049] The phosphate-based inorganic compound preferably contains a phosphite compound and a phosphate compound, and more preferably contains aluminum hydrogen phosphite or disaluminum phosphate. The inclusion of aluminum hydrogen phosphite or disaluminum phosphate tends to improve shape retention after thermal expansion.

[0050] These phosphate-based inorganic compounds can be used individually or in combination of two or more.

[0051] <Thermally expandable compound> In addition to phosphate-based inorganic compounds, other thermally expandable compounds may be used to assist the thermal expansion of phosphate-based inorganic compounds. There are no particular limitations on thermally expandable compounds other than phosphate-based inorganic compounds, as long as they expand when heated; for example, thermally expandable layered compounds and thermally expandable non-layered compounds can be used. One or more of these thermally expandable compounds can be used. When using thermally expandable compounds other than phosphate-based inorganic compounds, thermally expandable non-layered compounds are preferred from the viewpoint of shape retention after thermal expansion or adhesion to the substrate after thermal expansion. Examples of thermally expandable non-layered compounds other than phosphate-based inorganic compounds include thermally expandable non-layered organic compounds such as microspheres and nitrogen-containing blowing agents (components that foam when exposed to high temperatures, such as in a fire, unlike blowing agents used in the formation of urethane foam compositions), and thermally expandable non-layered inorganic compounds such as bicarbonates.

[0052] As thermally expandable layered compounds, particularly thermally expandable layered inorganic compounds, any known inorganic compound having a layered structure that expands when heated can be used, such as vermiculite, kaolin, mica, and thermally expandable graphite. Thermally expandable graphite is a crystalline compound that maintains a graphite layered structure, obtained by treating powders of natural graphite, pyrolysis graphite, etc., with inorganic acids such as sulfuric acid and nitric acid, and strong oxidizing agents such as concentrated nitric acid and permanganate. When exposed to temperatures of around 200°C or higher, these expand by more than 100 times, for example. These powders of natural graphite, pyrolysis graphite, etc., are available in various types, including those that have undergone deacidification treatment and further neutralization treatment, and all of them can be used.

[0053] The thermally expandable graphite used in this invention preferably has an average aspect ratio of 20 or more. An average aspect ratio of 20 or more allows for sufficient filling of the frame structure constituting the opening frame of building components such as fire-resistant resin sashes, and it can also be suitably used for steel frame covering.

[0054] The average aspect ratio is the ratio of the average horizontal diameter to the vertical thickness. Since the thermally expandable graphite used in this invention is generally flat, the vertical direction can be considered to coincide with the thickness direction and the horizontal direction with the diameter direction. Therefore, the aspect ratio is defined as the maximum horizontal dimension divided by the vertical thickness. Then, the aspect ratio is measured for a sufficiently large number of graphite pieces, i.e., 10 or more, and the average value is taken as the average aspect ratio. The average particle size of thermally expandable graphite can also be determined as the average value of the maximum horizontal dimensions. The maximum horizontal dimensions and thickness of thermally expandable graphite can be measured, for example, using a field emission scanning electron microscope (FE-SEM).

[0055] Examples of nitrogen-containing foaming agents include melamine, azo compounds, nitroso compounds, and hydrazine derivatives.

[0056] Examples of bicarbonates include sodium bicarbonate.

[0057] The content of thermally expandable compounds other than phosphoric acid-based inorganic compounds is preferably less than 10 parts by mass, more preferably less than 5 parts by mass, even more preferably less than 3 parts by mass, and particularly preferably 0 parts by mass, per 100 parts by mass of urethane compound. When the content of thermally expandable compounds other than phosphoric acid-based inorganic compounds is 10 parts by mass or more, the shape retention after thermal expansion tends to deteriorate. Specifically, the content of thermally expandable compounds other than phosphoric acid-based inorganic compounds is, for example, 0, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 1, 1.5, 1.8, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 19, or 20 parts by mass per 100 parts by mass of urethane compound, and may be within the range between any two of the values ​​exemplified here, or within the range less than either of them.

[0058] The content of the thermally expandable layered inorganic compound is less than 10 parts by mass, preferably less than 5 parts by mass, more preferably less than 3 parts by mass, and even more preferably 0 parts by mass, per 100 parts by mass of the urethane compound. If the content of the thermally expandable layered inorganic compound is 10 parts by mass or more, the shape retention after thermal expansion deteriorates. Specifically, the content of the thermally expandable layered inorganic compound is, for example, 0, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, or 9 parts by mass per 100 parts by mass of the urethane compound, and may be within the range between any two of the values ​​exemplified here, or within the range less than either of them.

[0059] Furthermore, the content of thermally expandable non-layered compounds other than phosphate-based inorganic compounds is preferably less than 10 parts by mass, more preferably less than 5 parts by mass, even more preferably less than 3 parts by mass, and even more preferably 0 parts by mass, per 100 parts by mass of urethane compound. Having the content of thermally expandable non-layered compounds other than phosphate-based inorganic compounds within this range provides a good balance between thermal expandability and shape retention after thermal expansion. Specifically, the content of thermally expandable non-layered compounds other than phosphate-based inorganic compounds is, for example, 0, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 19, and 20 parts by mass per 100 parts by mass of urethane compound, and may be within the range between any two of the values ​​exemplified here, or less than either of them.

[0060] Furthermore, the nitrogen-containing blowing agent content is preferably less than 10 parts by mass, more preferably less than 5 parts by mass, even more preferably less than 3 parts by mass, and most preferably 0 parts by mass, per 100 parts by mass of the urethane compound. If the nitrogen-containing blowing agent content is 10 parts by mass or more, the shape retention will deteriorate. Specifically, the nitrogen-containing blowing agent content is, for example, 0, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 19, or 20 parts by mass per 100 parts by mass of the urethane compound, and may be within the range between any two of the values ​​exemplified here, or less than either of them.

[0061] <Other ingredients> In this embodiment, plasticizers (softeners), antioxidants, processing aids, lubricants, tackifiers, fibrous organic compounds, other inorganic compounds excluding the phosphorus-based inorganic compounds and other thermally expandable compounds other than phosphorus-based inorganic compounds mentioned above, softeners, vulcanizing agents, crosslinking agents, carbonizing agents, flame retardants, etc., used in ordinary rubber compounding, may be used in combination, to the extent that they do not impair the effect.

[0062] <Other Inorganic Compounds> Other inorganic compounds can take the following shapes: spherical, ellipsoidal, cuboidal, rectangular, random, or fibrous, and may be hollow or solid. The average particle size of particulate inorganic compounds is, for example, 10 to 1000 μm, preferably 20 to 800 μm, more preferably 30 to 500 μm, and even more preferably 40 to 200 μm. "Average particle size" refers to the particle size at 50% of the cumulative value of the particle size distribution determined by laser diffraction / scattering. These may be used individually or in combination of two or more.

[0063] Other inorganic compounds include, for example, metal oxides such as alumina, silica, aluminosilicate, zinc oxide, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, and ferrites; hydrated inorganic substances such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide, and hydrotalcite; metal carbonates such as basic magnesium carbonate, calcium carbonate, magnesium carbonate, zinc carbonate, strontium carbonate, and barium carbonate; calcium salts such as calcium sulfate and calcium silicate; glass beads, silica-based balloons, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon balloons, charcoal powder, various metal powders, potassium titanate, magnesium sulfate, lead zirconate titanate, aluminum borate, molybdenum sulfide, silicon carbide, zinc borate, various magnetic powders, fly ash, inorganic hollow fillers, perlite, obsidian, perlite, pitchstone, diatomaceous earth, dewatered sludge, boron, sodium tetraborate hydrate (borax), and the like. These may be used individually or in combination of two or more. From the viewpoint of flame retardancy, the inorganic compound preferably contains aluminum hydroxide.

[0064] The content of other inorganic compounds is 10 to 500 parts by mass per 100 parts by mass of urethane compound, preferably 70 to 440 parts by mass, and more preferably 130 to 270 parts by mass. Having the content of other inorganic compounds within this range allows for a balance between hardness and flame retardancy.

[0065] The carbonizing agent generally has the effect of forming a thick foamed layer with superior heat insulation properties by dehydrating and carbonizing itself along with the carbonization of the binder due to fire. The carbonizing agent is not particularly limited as long as it has this effect, and the same carbonizing agents as those used in known foamed refractory materials can be used. Examples include polyhydric alcohols such as pentaerythritol, dipentaerythritol, and trimethylolpropane, as well as starch and casein. These can be used one or more at a time. Among these, dipentaerythritol is particularly preferred because it has excellent dehydration cooling effect and foamed layer formation effect.

[0066] Examples of flame retardants include organophosphorus compounds such as tricresyl phosphate and diphenylcresyl phosphate; chlorine compounds such as chlorinated polyphenyls, chlorinated polyethylenes, diphenyl chloride, triphenyl chloride, pentachloride fatty acid esters, perchloropentacyclodecane, chlorinated naphthalene, and tetrachlorophthalic anhydride; antimony compounds such as antimony trioxide and antimony pentachloride; phosphorus compounds such as phosphorus trichloride and phosphorus pentachloride; and other inorganic compounds such as zinc borate and sodium borate.

[0067] When both a carbonizing agent and a flame retardant are included, the weight ratio is preferably 2:8 to 8:2, and more preferably 3:7 to 7:3. Furthermore, the total amount of the carbonizing agent and flame retardant is preferably 10 to 500 parts by mass per 100 parts by mass of the urethane compound.

[0068] The urethane foam composition of the present invention may be used on its own, or it may be used with other components attached as appropriate. For example, the urethane foam composition may have components other than the urethane foam composition laminated on it, and a base material may be provided on at least one surface of the layer composed of the urethane foam composition. The base material may be a combustible material layer, a semi-noncombustible material layer, or a noncombustible material layer. The thickness of the base material is not particularly limited, but is for example 5 μm to 1 mm. Examples of materials used for the combustible material layer include one or more types such as cloth, paper, wood, and resin film. When the base material is a semi-noncombustible material layer or a noncombustible material layer, examples of materials used include metals and inorganic materials, and more specifically, woven or nonwoven fabrics made of glass fibers, ceramic fibers, carbon fibers, and graphite fibers. Alternatively, composite materials of these fibers and metals may be used, for example, aluminum glass cloth is preferred. Furthermore, an adhesive layer may be laminated on the layer composed of the urethane foam composition. The use of an adhesive layer makes it possible to easily adhere the urethane foam composition to other components. The adhesive layer may be provided on the above-mentioned substrate, or it may be formed directly on the surface of the fire-resistant material (urethane foam composition). Alternatively, a double-sided adhesive tape with adhesive layers on both sides of the substrate may be used. In this case, one adhesive layer may be attached to the urethane foam composition, and the other adhesive layer may be used to bond to other components.

[0069] <Manufacturing method> The method for producing the urethane foam composition of the present invention comprises a compounding step of blending a urethane raw material containing an isocyanate compound with a mixture (e.g., a mixed liquid such as an aqueous solution) containing a phosphate-based inorganic compound and a blowing agent. More specifically, the method comprises a compounding step of blending an isocyanate compound with an aqueous solution in which a phosphate-based inorganic compound is dispersed. In this compounding step, foam molding is performed by compounding accompanied by addition and stirring. The content of the blowing agent (e.g., water) in the mixture is preferably 10 parts by mass or more, more preferably 50 to 500 parts by mass, and even more preferably 80 to 200 parts by mass, per 100 parts by mass of the isocyanate compound. The mixture containing the phosphate-based inorganic compound and the blowing agent may also contain other additives such as inorganic compounds other than the phosphate-based inorganic compound, or other additives may be mixed with the urethane raw material and then blended with the mixture containing the phosphate-based inorganic compound and the blowing agent.

[0070] Furthermore, the method for manufacturing the urethane foam composition may include a drying step for drying the urethane foam composition (foam) after foam molding. The drying step may be carried out at, for example, 70 to 100°C (80°C in one example).

[0071] 2. Urethane foam joint filler The urethane foam joint material according to one embodiment of the present invention is a fire-resistant joint material using the above-described urethane foam composition. The urethane foam joint material may be composed of the above-described urethane foam composition. The urethane foam joint material can be used in various fields where properties such as elasticity, flexibility, thermal expansion, heat insulation, fire resistance, vibration damping, and sound insulation are required, but it can also be applied to known construction methods using fire-resistant expandable materials, and should be used according to the usage method of each construction method. There are no particular restrictions on the area of ​​use, and it can be widely used in places where fire resistance is required.

[0072] The urethane foam joint material is used to seal some or all of the gaps in penetrations provided in fire-resistant compartments. It is also suitably used in the fire-resistant parts of seismic isolation devices in buildings. Specifically, the gaps between power cables, communication cables, pipes, etc., passing through penetrations in fire-resistant compartments such as firewalls and floor slabs and firewalls can be covered with the fire-resistant joint material of the present invention, or a gasket molded to a shape suitable for the construction area can be attached. Furthermore, this fire-resistant joint material is used between the seismic isolation device body and the fire-resistant panel covering it, or at the edges of the fire-resistant panel, and is used by attaching it with adhesive or glue, or by fixing it with bolts or nails.

[0073] 3. Battery Furthermore, a battery according to another embodiment of the present invention comprises a member made of the above-mentioned urethane foam composition. The battery typically has at least one battery cell 3, and the above-mentioned urethane foam composition is attached to the battery as a member 1 such as a protective material or fire-resistant material (Figure 1). The urethane foam composition is typically attached to the surface of the battery cell. The battery may have one battery cell or two or more.

[0074] Battery cells include, but are not limited to, lithium-ion batteries, lithium-ion polymer batteries, nickel-metal hydride batteries, lithium-sulfur batteries, nickel-cadmium batteries, nickel-iron batteries, nickel-zinc batteries, sodium-sulfur batteries, lead-acid batteries, and air batteries.

[0075] Batteries are used in, but are not limited to, small electronic devices such as mobile phones and smartphones, laptop computers, automobiles, and power tools. [Examples]

[0076] The present invention will be described in detail below with reference to examples and comparative examples, but these examples are not intended to limit the present invention. In the following description, parts and percentages are based on mass.

[0077] A mixture of a phosphate-based inorganic compound and a thermally expandable layered inorganic compound was prepared by adding water (a foaming agent) to the proportions shown in the table. A urethane raw material (urethane prepolymer) was added to this aqueous solution and stirred. The mixture was then injected into a cylindrical mold with a diameter of 10 cm and a height of 15 cm and foamed. The mixture was left to stand in an oven at 80°C for 3 days with the mold to evaporate the water and obtain a sample of the urethane foam composition. The amount of water used was 200 parts by mass per 100 parts by mass of urethane prepolymer. Subsequently, as shown in Figure 2, each sample material was cut in half horizontally at a position 75 mm from the top surface, and a sample piece with dimensions of 30 mm width × 30 mm length × 10 mm height was taken from the center of the circle on the cut surface.

[0078] The materials used in the examples and comparative examples are as follows:

[0079] <Urethane prepolymer> • Polyether-based: "Hyprene EGH-401" manufactured by Mitsui Chemicals, Inc. • Polyether-based: "Hyprene L-80" manufactured by Mitsui Chemicals, Inc. • Polyester-based: "Takenate L-1270" manufactured by Mitsui Chemicals, Inc. <Phosphate-based inorganic compounds> • Aluminum hydrogen phosphite (Hydrogen Hydrogen Phosphite AL): Manufactured by Taihei Chemical Industry Co., Ltd. "NSF" • Dicatrix aluminum phosphate (Dicatrix AL): Manufactured by Taihei Chemical Industry Co., Ltd. Sodium phosphite (Na Phosphite): Manufactured by Taihei Chemical Industry Co., Ltd. • Ammonium polyphosphate (NH4 polyphosphate): "HP-APP II" manufactured by SCM Industrial Chemical Co., Ltd. <Thermally expandable layered inorganic compound> • Thermally expandable graphite: ADT501 (aspect ratio 25.2): ADT Corporation's "ADT501" with an aspect ratio of 25.2 <Foaming agent> ·water

[0080] The following characteristics were evaluated in the examples and comparative examples and summarized in the table. The measurement methods for each characteristic are shown below.

[0081] <Hardness (Deformability)> The sample pieces for the examples and comparative examples were prepared as test pieces measuring 30 mm in length, 30 mm in width, and 10 mm in thickness. The Shore E hardness was measured under a load of 1 kg in an environment of 21°C according to JIS K6253. Based on the measured values, the hardness was determined according to the following evaluation criteria. [Evaluation Criteria] ◎: Shore E hardness is less than 15. ○: Shore E hardness is 15 or higher and less than 20. △: Shore E hardness is 20 or higher, but less than 25. ×: The Shore E hardness is 25 or higher.

[0082] <Thermal expansion properties> The sample pieces for the examples and comparative examples were prepared as test pieces measuring 30 mm in length, 30 mm in width, and 10 mm in thickness. After leaving these in an atmosphere maintained at 600°C for 0.5 hours, their volume was measured, and the expansion ratio was calculated from this volume. Based on the volume expansion ratio, the thermal expansion properties were evaluated according to the following criteria. [Evaluation Criteria] ◎: The volume expansion ratio is 6 times or more. ○: The volume expansion ratio is 4 times or more and less than 6 times. △: The volume expansion ratio is 2 times or more, but less than 4 times. ×: The volume expansion ratio is less than 2 times.

[0083] <Shape retention after thermal expansion> For the examples and comparative examples, test specimens measuring 30 mm (length) x 30 mm (width) x 10 mm (thickness) were prepared. These specimens were left in an atmosphere maintained at 600°C for 0.5 hours. Then, using a three-point bending test fixture (upper pressing tip R1 mm and width 80 mm, lower two-point support R1 mm and width 80 mm, support distance 20 mm), the strength (three-point bending fracture strength) was measured when the test specimen was fractured at a compression speed of 50 mm / min. Here, a higher three-point bending fracture strength indicates better shape retention after thermal expansion. Based on the three-point bending fracture strength, the shape retention after thermal expansion was judged according to the following evaluation criteria. [Evaluation Criteria] ◎: The three-point bending fracture strength is 5.0 [N] or higher. ○: The three-point bending fracture strength is 3.0 [N] or greater and less than 5.0 [N]. △: The three-point bending fracture strength is 1.0 [N] or greater, and less than 3.0 [N]. ×: The three-point bending fracture strength is less than 1.0 [N].

[0084] <Adhesion after thermal expansion> Using the specimens from the examples and comparative examples, a specimen measuring 30 mm (length) x 30 mm (width) x 10 mm (thickness) was prepared, placed on a calcium silicate board, and left in an atmosphere maintained at 600°C for 0.5 hours to allow thermal expansion. The thermally expanded specimen was then pressed against the boundary between the calcium silicate board and the expanded specimen using the upper pressing jig (tip radius R1 mm and width 80 mm) of a three-point bending test jig at a speed of 50 mm / min (Figure 3), and the adhesion strength when the thermally expanded specimen was peeled off was measured. Based on the adhesion strength, the adhesion after thermal expansion was judged according to the following criteria. If the thermally expanded specimen fell before the upper pressing jig was pressed against it, the adhesion strength was set to 0.0 [N]. ◎:1.5[N] or more ○: 1.0[N] or greater, less than 1.5[N] △: 0.5[N] or greater, less than 1.0[N] ×: Less than 0.5 [N]

[0085] [Table 1]

[0086] Table 2

Claims

1. The urethane compound contains more than 100 parts by mass and up to 2000 parts by mass of a phosphoric acid-based inorganic compound per 100 parts by mass of the urethane compound. A urethane foam composition containing less than 10 parts by mass of a thermally expandable layered inorganic compound.

2. The urethane foam composition according to claim 1, wherein the urethane compound includes a urethane prepolymer or a structure derived from a urethane prepolymer.

3. The urethane foam composition according to claim 1, wherein the phosphate-based inorganic compound comprises at least one selected from aluminum hydrogen phosphite and aluminum disphosphate.

4. The urethane foam composition according to claim 1, wherein the content of the phosphate-based inorganic compound is 150 to 1600 parts by mass.

5. The urethane foam composition according to claim 1, wherein the content of the phosphate-based inorganic compound is 200 to 1200 parts by mass.

6. The urethane foam composition according to claim 1, wherein the content of the thermally expandable layered inorganic compound is less than 3 parts by mass.

7. The urethane foam composition according to claim 1, wherein the content of the thermally expandable layered inorganic compound is 0 parts by mass.

8. A urethane foam composition according to any one of claims 1 to 7, for use in a battery.

9. A battery comprising the urethane foam composition described in claim 8.

10. A fire-resistant joint material using the urethane foam composition described in any one of claims 1 to 7.

Images