JP2019183151A - Coating material - Google Patents

Abstract

To provide a coating material that has excellent foamability and can maintain heat-resistance protective performance of a base material.SOLUTION: The present invention provides a coating material, a coat of which forms a carbonized heat insulation layer upon a temperature rise. The coating material contains, as a coat forming component (A), a polyol component (a1) and a polyisocyanate component (a2). A cured coat of the coat forming component (A) has a 10% thermal weight loss temperature by thermogravimetry of less than 300°C.SELECTED DRAWING: None

Description

  The present invention relates to a novel coating material.

  For the purpose of protecting base materials such as steel, concrete, wood, and synthetic resin from fire, various foamable coating materials that foam by a temperature rise during a fire to form a carbonized heat insulating layer have been proposed. As such a foamable coating material, a synthetic resin blended with a foaming agent, a carbonizing agent, a flame retardant and the like is known. Such a coating material often has a heat-resistant protective performance that is determined by the coating thickness, and in order to obtain the desired heat-resistant protective performance, it should be applied uniformly at a predetermined coating thickness. In particular, the selection of a synthetic resin is important.

For example, as a foamable coating material for thick coating, a foamable coating material in which a flame retardant, a foaming agent, and a carbonizing agent are blended with a composition composed of a polyol component and a polyisocyanate component has been developed (for example, Patent Document 1). .

JP-A-5-70540

  However, in the case of the above-mentioned Patent Document 1, there is still room for improvement in order to obtain a desired heat-resistant protection performance because the expansion ratio is low compared to a covering material using an acrylic resin or an epoxy resin as a synthetic resin.

  In order to solve such problems, the present inventors have found that a coating material containing a specific film-forming component has excellent foamability and can maintain the heat-resistant protection performance of the substrate. The invention has been completed.

That is, the present invention has the following characteristics.
1. The coating is a coating material that forms a carbonized thermal insulation layer by increasing the temperature,
The coating material includes a polyol component (a1) and a polyisocyanate component (a2) as a film-forming component (A),
The cured coating of the film-forming component (A) has a 10% thermogravimetric decrease temperature in a thermogravimetric method of less than 300 ° C.
2. The film-forming component (A) has an isocyanurate ring. The coating | covering material as described in.

The present invention is a coating material in which the coating forms a carbonized thermal insulation layer by increasing the temperature, and includes a coating forming component whose 10% thermogravimetric decrease temperature in a thermogravimetric method is in a specific temperature range. When the temperature rises due to the above, it has excellent foamability, exhibits heat-resistant protection performance, and can enhance the heat-resistant protection of the substrate.

  Hereinafter, the present invention will be described in detail based on the embodiments.

  The present invention is a coating material in which the coating forms a carbonized heat insulation layer by a temperature rise (heating) such as a fire, and the coating material includes a polyol component (a1) and a polyisocyanate component (A) as a coating forming component (A). a2) is contained as an essential component. The polyol component (a1) and the polyisocyanate component (a2) are components that react to form a film.

The cured film of the film-forming component (A) shows a decrease in weight in the thermogravimetric method (TG method). Here, the weight reduction means that the weight decreases when the temperature is raised from 150 ° C. to 800 ° C. (the weight at 800 ° C. is smaller than the weight at 150 ° C.). The cured film of the film-forming component (A) of the present invention has a 10% thermogravimetric decrease temperature (temperature at the time of 10 wt% weight decrease) in the thermogravimetric method of less than 300 ° C (preferably 200 to 295 ° C, more preferably 205 to 290 ° C.). In such a case, when the temperature rises due to a fire or the like, the foamability is improved, an excellent carbonized heat insulating layer can be formed, and the heat resistance protection performance of the substrate can be enhanced. In the present invention, “α to β” has the same meaning as “α to β”.

Although the action mechanism is not limited, for example, the cured film of the film-forming component (A) starts to soften from around the thermogravimetric decrease starting temperature, and then undergoes a decomposition reaction such as a urethane bond as the temperature rises. It is a progression. When the 10% thermogravimetric decrease temperature in the thermogravimetric measurement method of the cured film of the film forming component (A) is within the above temperature range, the foaming is efficiently performed in a state in which the film is moderately softened without much decomposition. Since the carbonization reaction can proceed, it is considered that the foamability is improved, and further, the carbonized heat insulation layer can be stably formed.

The cured film of the film-forming component (A) of the present invention has a 25% thermal weight loss temperature (temperature at 25% weight reduction), preferably 230 to 350 ° C (more preferably 235 to 345 ° C), The 50% thermal weight loss temperature (temperature at the time of 50% weight loss) is preferably 250 to 400 ° C. (more preferably 255 to 380 ° C.), and further, the 25% thermal weight loss temperature and 50% heat The difference from the weight loss temperature is preferably 10 ° C. or higher (more preferably 15 ° C. or higher, more preferably 20 ° C. or higher). As a result, when the temperature rises due to a fire or the like, the foaming property is improved, it is possible to stably form an excellent carbonized heat insulating layer, and further to prevent the formed carbonized heat insulating layer from falling off. The heat protection performance can be further enhanced. In addition, the 25% thermal weight reduction temperature and the 50% thermal weight reduction temperature are each equal to or higher than the above lower limit value, thereby exhibiting sufficient flame retardancy and excellent foaming properties, and providing a stable carbonized layer. Can be formed. Further, when the 25% thermal weight reduction temperature and the 50% thermal weight reduction temperature are each not more than the above upper limit values, sufficient foamability can be ensured.

The action mechanism is not limited. For example, the 25% thermal weight reduction temperature or the 50% thermal weight reduction temperature refers to a decomposition reaction such as a urethane bond derived from the film-forming component (A). When the temperature is about 25% or about 50% (half), and this temperature is within the above range, foaming and carbonization can be efficiently performed. For this reason, it is considered that excellent foamability is exhibited, and furthermore, the carbonized heat insulating layer can be stably formed.

  Furthermore, the cured film of the film forming component (A) of the present invention has an exothermic peak in the differential thermal analysis method (DTA method). Specifically, the film forming component (A) of the present invention preferably has an exothermic peak in a temperature range of 150 to 800 ° C. (more preferably 180 to 600 ° C.). The maximum value of the exothermic peak is preferably in the temperature range of 200 to 400 ° C. (more preferably 250 to 380 ° C.).

In the present invention, the thermogravimetric measurement method and differential thermal analysis method of the cured film of the film forming component (A) were measured using the cured film containing the polyol component (a1) and the polyisocyanate component (a2) as a sample. Is. The thermogravimetry method and the differential thermal analysis method may be performed by using a differential thermal analyzer (for example, “Differential Thermobalance Thermo”).
plus EVO2 TG-DTA series ”manufactured by Rigaku Corporation, etc.), 3 ± 1 mg of a sample is taken in a platinum sample pan, α-alumina is used as a standard substance, and the heating rate is 20 ° C. / Measured by changing from 100 to 900 ° C. in minutes.

In the present invention, the film forming component (A) preferably has an isocyanurate ring. Thereby, it is possible to form a stable carbonized heat insulation layer when the temperature rises due to a fire or the like, and it is particularly excellent in adhesion to the base material at a high temperature, and the carbonized heat insulation layer can be prevented from falling off.

Although the action mechanism is not limited, it has the effect | action which shifts the 50% weight reduction | decrease temperature of a cured film to the high temperature side because a film formation component (A) has an isocyanurate ring. That is, the flame retardancy of the cured film of the film forming component (A) can be increased and decomposition can be suppressed. Furthermore, even if it has an isocyanurate ring, since the softening of the cured coating is difficult to be inhibited, the coating can be efficiently foamed to form a stable carbonized thermal insulation layer. It is thought that the omission of the can be suppressed.

In the present invention, in order for the film forming component (A) to have an isocyanurate ring, at least one of the polyol component (a1) and the polyisocyanate component (a2) contains a compound having an isocyanurate ring, or a film is formed. Examples of the component (A) include a compound (a3) having an isocyanurate ring (excluding the polyol component (a1) and the polyisocyanate component (a2)). In this invention, the aspect containing the compound which has an isocyanurate ring especially as a polyol component (a1) is preferable. Thereby, the effect of this invention can fully be acquired.

Hereafter, the structure of the film formation component (A) of this invention is demonstrated concretely.
The film forming component (A) includes a polyol component (a1) and a polyisocyanate component (a2).

The polyol component (a1) of the present invention is not particularly limited. For example, polyether polyol, polyester polyol, acrylic polyol, epoxy-containing polyol, silicone-containing polyol, fluorine-containing polyol, castor oil, castor oil-modified polyol, polycarbonate polyol, Lactone polyols, polybutadiene polyols, polypentadiene polyols and the like can be mentioned, and one or more selected from these can be used.

In the present invention, it is preferable that a polyether polyol is included as the polyol component (a1). The molecular weight of the polyether polyol is preferably 1000 or more (more preferably 3000 to 20000, even more preferably 5000 to 18000, particularly preferably 6000 to 15000, most preferably 6500 to 12000). By including such a polyol component, the 10% thermogravimetric decrease temperature in the thermogravimetric method can sufficiently satisfy the above range, and has an excellent foaming property and can form a stable carbonized heat insulating layer. It is possible, and the heat-resistant protection performance of the substrate can be further enhanced. In the present invention, the molecular weight of the polyol component (a1) is a number average molecular weight (Mn), and is a so-called polystyrene equivalent molecular weight obtained by gel permeation chromatography using a polystyrene polymer as a reference.

The polyether polyol can be obtained, for example, by addition polymerization of polyhydric alcohols such as trimethylolpropane, glycerin, hexanetriol, pentaerythritol derivatives, sorbitol, and neopentyl glycol, and alkylene oxides such as ethylene oxide and propylene oxide. Is. In the present invention, a polymer obtained by addition polymerization of the above polyhydric alcohols with ethylene oxide and / or propylene oxide is preferable, and one having ethylene oxide and / or propylene oxide added to the terminal is more preferable. is there. Further, the polyether polyol preferably includes a polyether polyol having three or more functional groups having active hydrogen atoms (functional group number of 3 or more). In this case, since it is excellent in curability and can form a film stably, the effect of this invention is easy to be acquired. A hydroxyl group is suitable as the functional group having an active hydrogen atom.

Such a polyether polyol preferably has a hydroxyl value of 3 to 150 mgKOH / g (more preferably 5 to 100 mgKOH / g, still more preferably 7 to 40 mgKOH / g, and most preferably 10 to 30 mgKOH / g). By using such a polyol component, it is possible to exhibit excellent foaming properties and to improve the heat resistance protection performance of the substrate.

Moreover, it is preferable that content of the said polyether polyol is 50 weight% or more (more preferably 60 weight% or more, more preferably 70 weight% or more) with respect to the polyol component (a1) whole quantity.

Moreover, in this invention, it is preferable that a fluorine-containing polyol is included as a polyol component (a1). As a result, when the temperature rises due to a fire or the like, it is possible to exhibit excellent foamability and to stably form the carbonized heat insulation layer, and to prevent the carbonization heat insulation layer from dropping off.

Such a fluorine-containing polyol is not particularly limited. For example, a fluorine-containing monomer such as a fluoroolefin monomer or a fluoroalkyl group-containing acrylic monomer, a hydroxyl group-containing vinyl monomer, and other polymerizable monomers as necessary. Can be obtained by copolymerization. Examples of the fluoroolefin monomer include perfluoroolefins such as tetrafluoroethylene, chlorotrifluoroethylene, and hexafluoropropylene, vinyl fluoride, and vinylidene fluoride. Examples of the fluoroalkyl group-containing acrylic monomer include perfluoromethyl methacrylate, perfluoroisononylmethyl methacrylate, 2-perfluorooctylethyl acrylate, 2-perfluorooctylethyl methacrylate, and trifluoroethyl acrylate. These can be used alone or in combination of two or more. In the present invention, it is preferable to use at least one selected from tetrafluoroethylene and chlorotrifluoroethylene, more preferably chlorotrifluoroethylene.

Examples of the hydroxyl group-containing vinyl monomer include hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, hydroxypropyl vinyl ether, hydroxybutyl vinyl ether, and hydroxypentyl vinyl ether; ethylene glycol monoallyl ether, diethylene glycol monoallyl ether, triethylene glycol monoallyl ether Hydroxyallyl ethers such as 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, 4-hydroxyethyl (meth) acrylate, hydroxyl-containing (meth) acrylate such as 4-hydroxybutyl (meth) acrylate, etc. One or more of these can be used.

Examples of other polymerizable monomers include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, n-amyl (meth) acrylate, Isoamyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate, cyclohexyl (meth) (Meth) acrylic acid alkyl esters such as acrylate; dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, dimethylamino (meth) acrylate, aminoethyl (meth) ) Amino group-containing monomers such as acrylate and diethylaminoethyl (meth) acrylate; acrylic acid, methacrylic acid, crotonic acid, maleic acid or its monoalkyl ester, itaconic acid or its monoalkyl ester, fumaric acid or its monoalkyl ester, etc. Carboxyl group-containing monomers; Amide-containing monomers such as (meth) acrylamide and ethyl (meth) acrylamide; Nitrile group-containing monomers such as (meth) acrylonitrile; Epoxy group-containing monomers such as glycidyl (meth) acrylate; Styrene, methylstyrene, chloro Aromatic vinyl monomers such as styrene and vinyltoluene; Vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate and vinyl pivalate; Olefin monomers such as ethylene and propylene Etc., and one or two or more of these can be used if necessary.

  Such a fluorine-containing polyol preferably has a fluorine content of 15 to 50% by weight (more preferably 20 to 40% by weight). Moreover, it is preferable that a hydroxyl value is 5-100 mgKOH / g (more preferably 10-80 mgKOH / g). Furthermore, it is preferable that molecular weight [number average molecular weight (Mn)] is 5000-100000 (more preferably 8000-60000). By including such a fluorine-containing polyol, when the temperature rises due to a fire or the like, the film exhibits excellent foaming properties to form a carbonized heat insulating layer, and can suppress ashing and shrinkage even in a high-temperature atmosphere. It is possible to improve the heat-resistant protection performance of the substrate.

The content of the fluorine-containing polyol may be in a range that satisfies the range of the 10% thermogravimetric decrease temperature in the thermogravimetric method in the cured film of the film forming component (A), and is based on the total amount of the polyol component (a1). The solid content is preferably 0.1 to 30% by weight (more preferably 1 to 10% by weight). By satisfying this range, the effects of the present invention can be sufficiently exerted.

（式１）
例えば、イソシアヌル酸トリス（ヒドロキシアルキル）エステル等が使用できる。イソシアヌル酸トリス（ヒドロキシアルキル）エステルとしては、例えば、イソシアヌル酸トリス（２ヒドロキシエチル）、イソシアヌル酸トリス（２ヒドロキシプロピル）、イソシアヌル酸トリス（２ヒドロキシブチル）、イソシアヌル酸トリス（２,３ジヒドロキシプロピル）等のイソシアヌレート環と水酸基を有するアルキルエステルが挙げられる。 Furthermore, in this invention, it is preferable that the polyol compound (a1 ') which has an isocyanurate ring is included as a polyol component (a1). Examples of the polyol compound (a1 ′) having an isocyanurate ring include compounds having an isocyanurate ring (formula 1) and two or more hydroxyl groups,

(Formula 1)
For example, isocyanuric acid tris (hydroxyalkyl) ester can be used. Examples of the isocyanuric acid tris (hydroxyalkyl) ester include isocyanuric acid tris (2 hydroxyethyl), isocyanuric acid tris (2 hydroxypropyl), isocyanuric acid tris (2 hydroxybutyl), isocyanuric acid tris (2,3 dihydroxypropyl). And alkyl esters having an isocyanurate ring and a hydroxyl group.

  Moreover, as a polyol compound (a1 ') which has an isocyanurate ring, the acrylic polyol etc. which have an isocyanurate ring can also be used, for example. As such a compound, for example, when an acrylic polyol is produced, an isocyanuric acid derivative having a reactive functional group selected from a vinyl group, an acryloyl group, a thiol group, an alkoxysilyl group, a carboxyl group, a glycidyl group, and the like is reacted. Can be obtained. For example, a combination of a polymerizable unsaturated double bond and a vinyl group, an acryloyl group, or a thiol group or an alkoxysilyl group, a glycidyl group and a carboxyl group, an amino group and a glycidyl group, or the like may be used for the reaction here.

The polyol compound (a1 ′) having an isocyanurate ring is preferably 0.01 to 20% by weight (more preferably 0.05 to 15% by weight, still more preferably 0.1 to 10%) in the polyol component (a1). % By weight). Thereby, it is possible to form a stable carbonized heat insulation layer when the temperature rises due to a fire or the like, and it is particularly excellent in adhesion to the base material at a high temperature, and the carbonized heat insulation layer can be prevented from falling off.

Examples of the polyisocyanate component (a2) of the present invention include toluene diisocyanate (TDI), 4,4-diphenylmethane diisocyanate (pure-MDI), polymeric MDI, xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), and isophorone. Diisocyanate (IPDI), hydrogenated XDI, hydrogenated MDI, etc., or allophanated, biuretized, dimerized (uretidione), trimerized (isocyanurate), adducted, carbodiimidated derivatives; and Examples include blocked isocyanates blocked with alcohols, phenols, ε-caprolactam, oximes, active methylene compounds, etc., and one or more selected from these can be used. .

In the present invention, it is preferable that hexamethylene diisocyanate (HMDI) and / or a derivative thereof (hereinafter also referred to as “HMDIs”) is included as the polyisocyanate component (a2). The content of the HMDIs is preferably 90% by weight or more (more preferably 95% by weight or more) with respect to the total amount of the polyisocyanate component (a2). Moreover, the aspect in which a polyisocyanate component (a2) consists only of HMDIs is also suitable.

In the present invention, as a preferred derivative of the polyisocyanate component (a2), a compound having a biuret structure (hereinafter also simply referred to as “biuret body”) and / or a polyisocyanate compound having an isocyanurate ring (hereinafter simply referred to as “isocyanate”). Also referred to as “nurate”. When a biuret body is included, the curability of the formed film is excellent, and when the temperature rises due to a fire or the like, the foaming property is more excellent, and the heat resistance protection of the substrate can be enhanced. In addition, when an isocyanurate body is included, it is possible to form a stable carbonized heat insulation layer when the temperature rises due to a fire or the like, and particularly has excellent adhesion to the substrate, and suppresses falling off of the carbonized heat insulation layer, etc. Can do. These can also be used in combination.

The mixing of the polyol component (a1) and the polyisocyanate component (a2) is preferably 0.6 to 3.5 (more preferably 1.) in terms of the NCO / OH equivalent ratio of the polyol component (a1) and the polyisocyanate component (a2). 0 to 2.5, more preferably 1.1 to 1.9). In such a case, it is excellent in sclerosis | hardenability, a uniform film can be formed with desired thickness, foamability can be improved further, and the heat-resistant protection performance of a base material can be improved.

In the present invention, as the film forming component (A), in addition to the polyol component (a1) and the polyisocyanate component (a2), a compound (a3) having an isocyanurate ring can also be included. The compound (a3) having an isocyanurate ring preferably reacts with the polyol component (a1) and / or the polyisocyanate component (a2) to form a film. For example, an alkoxysilyl group, a carboxyl group, a glycidyl group And isocyanuric acid derivatives having at least one reactive functional group such as In this case, what has an alkoxy silyl group, a glycidyl group, a carboxyl group, an amino group etc. should just be used as the said polyol component (a1) and / or the said polyisocyanate component (a2).

  The compounding amount of the compound (a3) having an isocyanurate ring is preferably 0.1 to 30 parts by weight (more than 100 parts by weight of the solid content of the polyol component (a1) and the polyisocyanate component (a2)). Preferably it is 0.5-20 weight part, More preferably, it is 1-15 weight part. In such a case, the effects of the present invention can be sufficiently exerted.

  In this invention, the curing catalyst which accelerates | stimulates reaction of a polyol component (a1) and a polyisocyanate component (a2) can be used together. A curing catalyst is a substance having an action of promoting the curing by reaction of isocyanate groups. Examples of the curing catalyst include various amine-based catalysts, organometallic catalysts, inorganic catalysts, and the like. Examples of the amine catalyst include ethylenediamine, triethylenediamine, triethylamine, ethanolamine, diethanolamine, and hexamethylenediamine, a derivative thereof, or a mixture with a solvent. Examples of the organometallic catalyst include organometallic compounds such as dibutyltin dilaurate and dibutyltin diacetate; organometallic salts such as potassium acetate, zinc stearate, calcium stearate, lead stearate, aluminum stearate and tin octylate. Examples of the inorganic catalyst include tin chloride. These can be used by 1 type (s) or 2 or more types, and can also be mixed and used for a solvent. In the present invention, it is particularly preferable to include an organometallic catalyst. In this case, curing can be promoted and the curability of the film-forming component (A) can be enhanced, so that the effect of the present invention can be enhanced.

  Furthermore, the coating material of the present invention can contain, for example, a foaming agent (B), a carbonizing agent (C), a flame retardant (D), a filler (E), and the like.

Examples of the foaming agent (B) include melamine and derivatives thereof, dicyandiamide and derivatives thereof, azobistetrasome and derivatives thereof, azodicarbonamide, urea and thiourea. These can be used alone or in combination of two or more. The content of the foaming agent (B) is preferably 10 to 200 parts by weight (more preferably 20 to 150 parts by weight) with respect to 100 parts by weight of the solid content of the film forming component (A). In addition, the foaming agent (B) of the present invention imparts a foaming action to the coating by a temperature rise during a fire or the like, and specifically, when the temperature of the coating surface is preferably 200 ° C. or higher. It gives a foaming action.

Examples of the carbonizing agent (C) include pentaerythritol, dipentaerythritol, trimethylolpropane, starch, and casein. These can be used alone or in combination of two or more. In the present invention, pentaerythritol and dipentaerythritol are particularly preferable in that they are excellent in dehydration cooling effect and carbonized heat insulation layer forming action. The content of the carbonizing agent (C) is preferably 10 to 200 parts by weight (more preferably 20 to 120 parts by weight) with respect to 100 parts by weight of the solid content of the film forming component (A). In addition, the carbonizing agent (C) of this invention provides the effect | action which forms a carbonization heat insulation layer by carrying out dehydration carbonization with carbonization of the said film formation component (A) by the temperature rise at the time of a fire etc.

Examples of the flame retardant (D) include organic phosphorus compounds such as tricresyl phosphate and diphenyl cresyl phosphate; chlorinated polyphenyl, chlorinated polyethylene, diphenyl chloride, triphenyl chloride, chlorinated paraffin, and pentachloride fatty acid. Chlorine compounds such as esters, perchloropentacyclodecane, chlorinated naphthalene and tetrachlorophthalic anhydride; antimony compounds such as antimony trioxide and antimony pentachloride; phosphorus trichloride, phosphorus pentachloride, ammonium phosphate, ammonium polyphosphate, phosphorus Phosphorus compounds such as melamine acid, melamine polyphosphate, melam polyphosphate, melem polyphosphate, boron phosphate, boron polyphosphate, aluminum phosphate, aluminum aluminum phosphate; and other inorganic compounds such as zinc borate and sodium borate It is done. These can be used alone or in combination of two or more. In this invention, it is preferable that a phosphorus compound is included as a flame retardant (D). The content of the flame retardant (D) is preferably 100 to 1000 parts by weight (more preferably 200 to 800 parts by weight) with respect to 100 parts by weight of the solid content of the film forming component (A).

Examples of the filler (E) include talc, calcium carbonate, sodium carbonate, aluminum oxide (alumina), titanium oxide, zinc oxide, silica, clay, clay, shirasu, mica, quartz sand, quartzite powder, quartz powder, and barium sulfate. Etc. These can be used alone or in combination of two or more. The content of the filler (E) is preferably 3 to 200 parts by weight (more preferably 5 to 150 parts by weight) with respect to 100 parts by weight of the solid content of the film forming component (A).

Furthermore, in this invention, in addition to the said component, a metal hydrate (F) and a fiber (G) can also be included. The metal hydrate (F) exhibits endothermic properties due to a dehydration reaction or the like when the temperature rises, and is different from the filler (E). Examples of such metal hydrate (F) include aluminum hydroxide and magnesium hydroxide. These can be used alone or in combination of two or more. The average particle size of the metal hydrate (F) is preferably 0.1 to 20 μm (more preferably 0.2 to 15 μm, still more preferably 0.3 to 8 μm, most preferably 0.4 to 3 μm). It is. The content of the metal hydrate (F) is preferably 1 to 200 parts by weight (more preferably 5 to 100 parts by weight, further preferably 8 parts by weight) with respect to 100 parts by weight of the solid content of the film forming component (A). ~ 80 parts by weight).

In the present invention, it is preferable to use the filler (E) and the metal hydrate (F) in combination. In this case, the filler (E) and the metal hydrate (F) have a weight ratio of 1: 9 to 9: 1. (More preferably, 2: 8 to 8: 2). In this case, since the foaming property, in particular, the shrinkage of the carbonized heat insulation layer under high temperature can be suppressed and a stable carbonized heat insulation layer can be formed, the effect of the present invention can be enhanced. The average particle diameter is measured by a laser diffraction particle size distribution measuring device.

A fiber (G) can improve thick coating property and can suppress the crack of a film. In addition, the fiber (G) can make it difficult to cause sagging of the film when the temperature rises due to a fire or the like, and can increase the thermal conductivity inside the film. As a result, excellent foamability is exhibited, a uniform carbonized heat insulating layer can be formed, and the heat resistance protection performance of the substrate can be enhanced. Examples of such fibers (G) include acrylic fibers, acetate fibers, aramid fibers, copper ammonia fibers (cupra), nylon fibers, novoloid fibers, pulp fibers, viscose rayon, vinylidene fibers, polyester fibers, polyethylene fibers, Organic fiber such as polyvinyl chloride fiber, polyclar fiber, vorinic fiber, polypropylene fiber, cellulose fiber, carbon fiber, rock wool fiber, glass fiber, silica fiber, alumina fiber, silica-alumina fiber, slag wool fiber, ceramic fiber, carbon Examples thereof include inorganic fibers such as fibers and silicon carbide fibers. These can be used alone or in combination of two or more.

In the present invention, the fibers (G) preferably include inorganic fibers, and among them, artificial mineral fibers such as rock wool fibers, slag wool fibers, and glass fiber ceramic fibers are preferable. As a result, cracking of the film can be further suppressed, and when the temperature rises due to a fire or the like, it can be made difficult to cause sagging of the film, and the thermal conductivity inside the film can be further increased. it can. As a result, it is possible to exhibit excellent foaming properties uniformly to the inside (core part) of the coating, to form a more uniform carbonized heat insulating layer, and to further enhance the heat-resistant protection performance of the substrate.

The size of the fiber (G) (fiber length and fiber diameter) may be set according to the performance of the coating material, the application base material, the application tool, etc., and the average fiber length is preferably 10 to 10%. The average fiber diameter is preferably in the range of 1000 μm (more preferably 15 to 800 μm, more preferably 20 to 600 μm), and preferably 0.5 to 10 μm (more preferably 1 to 8 μm). The aspect ratio (fiber length / fiber diameter) is preferably 3 to 300 (more preferably 5 to 200). When the above range is satisfied, the thick coatability is increased, and it is difficult to cause cracking of the formed film, and when the temperature rises due to a fire or the like, it is difficult to cause sagging of the film. Can be formed. The content of the fiber (G) is preferably 0.5 to 30 parts by weight (more preferably 1 to 25 parts by weight, further preferably 2 to 2 parts by weight) with respect to 100 parts by weight of the solid content of the film forming component (A). 20 parts by weight).

It is preferable that the coating material of the present invention further contains a high boiling point compound (H). The high boiling point compound (H) is a liquid at 20 ° C. and a high boiling point liquid compound having a boiling point of 100 ° C. or higher (more preferably 150 ° C. or higher, more preferably 200 ° C. or higher). By including such a high boiling point compound (H), the dispersion stability and the like of powder components such as the component (B) to the component (G) can be enhanced. Further, by mixing and reacting with the polyisocyanate component, it is possible to form a good film having excellent adhesion, particularly the elasticity of the film is improved, and the crack of the film can be prevented. In addition, when the coating is exposed to high temperatures due to a fire or the like, it contributes to appropriate softening of the coating and further enhances foaming properties, suppresses the falling (peeling) of the formed carbonized thermal insulation layer, and the like. Heat protection performance can be improved.

The high boiling point compound (H) is not particularly limited as long as it satisfies the above conditions. For example, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diheptyl phthalate, dihexyl phthalate, di-2-ethylhexyl phthalate Phthalate compounds such as diisononyl phthalate, diisodecyl phthalate, diundecyl phthalate, butyl benzyl phthalate; diethyl adipate, dibutyl adipate, diisobutyl adipate, dihexyl adipate, di-2-ethylhexyl adipate, adipic acid Aliphatic dibasic acid esters such as dioctyl, diisononyl adipate, diisodecyl adipate, bis (butyldiglycol) adipate, diethyl sebacate, dibutyl sebacate, dihexyl sebacate, di-2-ethylhexyl sebacate Compound: Adipic acid polyester such as adipic acid-1,3 butylene glycol polyester, adipic acid-1,2 propylene glycol polyester; dimethyl maleate, diethyl maleate, dibutyl maleate, dihexyl maleate, di maleate Maleic ester compounds such as 2-ethylhexyl, diisononyl maleate, diisodecyl maleate; triethyl phosphate, tributyl phosphate, tri-2-ethylhexyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, phosphorus Phosphoric acid ester compounds such as acid-2-ethylhexyldiphenyl;

Trimetic acid ester compounds such as tris-2-ethylhexyl trimellitate; ricinoleic acid ester compounds such as methylacetyl lysinolate; di-2-ethylhexyl epoxyhexahydrophthalate, diepoxystearyl epoxyhexahydrophthalate, butyl epoxidized fatty acid, Epoxy ester compounds such as epoxidized fatty acid 2-ethylhexyl, epoxidized soybean oil, and epoxidized linseed oil; benzoic acid ester compounds such as benzoic glycol ester; 1-phenyl-1-xylylethane, 1-phenyl-1-ethyl Examples thereof include aromatic hydrocarbon compounds such as phenylethane, lactones such as γ-butyrolactone, mixtures of petroleum resins (aromatic hydrocarbon fraction polymer having 8 to 10 carbon atoms) and styrylxylene, and the like. These can be used alone or in combination of two or more.

In the present invention, the high-boiling compound (H) preferably contains at least one selected from a phthalate ester compound, an aliphatic dibasic acid ester compound, and a phosphate ester compound. It is preferable to contain 1 or more types chosen from 4-11 (more preferably 5-10, still more preferably 6-9) phthalic acid ester compounds and aliphatic dibasic acid ester compounds. Specific examples thereof include, for example, diisononyl phthalate, diisononyl adipate, and the like.

The content of the high boiling point compound (H) is preferably 5 to 150 parts by weight (more preferably 10 to 100 parts by weight, still more preferably 15 to 100 parts by weight with respect to 100 parts by weight of the solid content of the film forming component (A). 80 parts by weight). When the above range is satisfied, the dispersibility of the powder component is enhanced, the coating property is excellent, and the temperature rises due to a fire or the like, the foam has excellent foaming properties and maintains the heat resistance protection performance of the substrate. Can be fully demonstrated.

  Other additives may be used as long as they do not significantly inhibit the effects of the present invention. For example, pigments, wetting agents, plasticizers, lubricants, preservatives, antifungal agents, antialgae agents, antibacterial agents, and thickeners. , Leveling agents, dispersants, antifoaming agents, crosslinking agents, silane coupling agents, ultraviolet absorbers, antioxidants, halogen scavengers, diluent solvents and the like.

Among these, examples of the antioxidant include phosphorus-based, sulfur-based or hindered phenol-based antioxidants. These can be used alone or in combination of two or more. By including such an antioxidant, it is possible to suppress deterioration of the coating not only during normal times but also during a temperature rise due to a fire or the like, and it is possible to improve the properties of the carbonized heat insulating layer formed by the temperature rise. .

  The coating material of the present invention is preferably a two-pack type coating material having a main agent containing the polyol component (a1) and a curing agent containing the polyisocyanate component (a2). That is, the main agent and the curing agent may be stored in separate packages at the time of distribution, and these may be mixed at the time of use (at the time of application). In this case, the compound (a3) having the isocyanurate ring, the foaming agent (B), the carbonizing agent (C), the flame retardant (D), and the filler (E) (further, the metal hydration The product (F), fiber (G), plasticizer (H), curing catalyst) may be mixed with at least one of the main agent and the curing agent, but in the present invention, it is preferably mixed with the main agent. Moreover, each component can also be added at the time of mixing of a main ingredient and a hardening | curing agent.

  The coating material of the present invention is suitable as a foamable fireproof coating material applied to the surface coating of structures such as buildings and civil engineering structures. Specifically, it can be applied to various base materials such as walls, columns, floors, beams, roofs, stairs, ceilings, doors and the like. Examples of the applicable substrate include concrete, mortar, siding board, extrusion board, gypsum board, perlite board, brick, plastic, wood, metal, steel frame (steel material), glass, porcelain tile and the like. These base materials may be those with a coating already formed on the surface, those with some base treatment (rust prevention treatment, flame retardant treatment, etc.), those with wallpaper attached, and the like.

  When the coating material of the present invention is applied to a substrate, for example, it may be applied in one or several steps using a coating tool such as a spray, a roller, a brush, or a trowel. It is applied so that the dry film thickness per step is preferably 400 μm or more (more preferably 500 to 5000 μm). Thereby, a thick film can be formed with few coating processes. The film thickness finally formed may be appropriately set depending on desired functionality, application site, and the like, but is preferably about 0.4 to 5 mm.

  In this invention, in order to protect the film formed with the said coating | covering material, a top coat material can also be further applied as needed. Such a top coating material can be formed by applying a known coating material. As the top coating material, for example, a coating material such as an acrylic resin type, a urethane resin type, an acrylic silicon resin type, a fluorine resin type, an epoxy resin type, or a vinyl acetate resin type can be used. These can be used alone or in combination of two or more, and two or more coating materials can be laminated and applied. The top coating material may be applied by a known coating method, and for example, a coating instrument such as a spray, a roller, or a brush can be used.

  Examples are given below to clarify the features of the present invention. However, the present invention is not limited to this range.

<Film forming components (A1 to A9)>
About (a1) component and (a2) component, what mixed the polyol component shown in Table 1 and the polyisocyanate component by NCO / OH equivalent ratio was made into film formation component (A1)-(A9).
Table 1 shows the results of measurement (150 to 800 ° C.) of the cured film of the film forming components (A1) to (A9) by thermogravimetry and differential thermal analysis. In addition, the following were used as a raw material.

・ Polyol component (a1)
(A1-1): Polyether polyol (ethylene oxide and propylene oxide polymer using glycerin as an initiator, number average molecular weight 10,000, number of functional groups 3, hydroxyl value 17 mgKOH / g, terminal ethylene oxide addition)
(A1-2): Polyether polyol (polymer of ethylene oxide and propylene oxide using glycerol as an initiator, number average molecular weight 7000, functional group number 3, hydroxyl value 24 mgKOH / g, terminal ethylene oxide addition)
(A1-3): Polyether polyol (ethylene oxide and propylene oxide polymer using propylene glycol as an initiator, number average molecular weight 5,100, functional group number 3, hydroxyl value 33 mgKOH / g, terminal ethylene oxide addition)
(A1-4): Polyether polyol (ethylene oxide and propylene oxide polymer using propylene glycol as an initiator, number average molecular weight 3000, functional group number 3, hydroxyl value 56 mgKOH / g, terminal ethylene oxide addition)
(A1-5): Polyether polyol (polymer with propylene oxide starting from glycerin, number average molecular weight 700, number of functional groups 3, hydroxyl value 225 mgKOH / g, terminal propylene oxide addition)
(A1-6): Ethylene trifluoride copolymer (chlorotrifluoroethylene-vinylether-hydroxyalkylvinyltethel copolymer, hydroxyl value 52 mgKOH / g, solid content 60% by weight, containing aromatic hydrocarbon solvent)
Polyol compound having an isocyanurate ring (a1 ′)
(A1′-1) Isocyanuric acid tris (2hydroxyethyl) (hydroxyl value 645 mgKOH / g)

-Polyisocyanate component (a2)
(A2-1) Biuret type hexamethylene diisocyanate (NCO content 23.5%)
(A2-2) Isocyanurate-type hexamethylene diisocyanate (NCO content 23.1%)

-Foaming agent (B): Melamine-Carbonizing agent (C): Pentaerythritol-Flame retardant (D): Ammonium polyphosphate-Filler (E): Titanium oxide-Metal hydrate (F): Aluminum hydroxide (average Particle size 1μm)
Fiber (G): Rock wool fiber (average fiber length 125 μm, average fiber diameter 4.5 μm)
・ High boiling point compound (H): diisononyl phthalate (boiling point 420 ° C.)
・ Curing catalyst (I): Organometallic catalyst ・ Additive 1: Dispersant, antifoaming agent, etc. ・ Additive 2: Plasticizer, diluent solvent, etc.

(Manufacturing method of coating material)
Coating materials 1 to 9 were prepared according to the film forming components shown in Table 1 and the formulation shown in Table 2. At this time, (a1) component, (B) component to (E) component, (I) component and additives are mixed by a conventional method to prepare a main agent, and then (a2) component (curing agent) is mixed. Then, coating materials 1 to 9 were obtained.

(Examples 1-8, Comparative Example 1)
A coating material was sprayed on the entire surface of a steel plate (150 mm long x 70 mm wide x 1.6 mm thick) that had been pre-rusted and coated (dry film thickness 1.5 mm) and allowed to cure at room temperature (25 ° C.) for 7 days. The test piece [I] was used, and the following evaluation was performed.
<Curability evaluation>
The curability (presence or absence of tack) of the formed film was evaluated by a finger touch test. The evaluation criteria are as follows.
A: No tack and good curability B: Some tack remains C: Some tack remains D: Hardening

<Heat-resistant protection evaluation 1>
Based on the ISO 5660-1 cone calorimeter method, using an electric heater (CONEIII, manufactured by Toyo Seiki Co., Ltd.), the foaming magnification when the radiant heat of 50 kW / m ² was radiated to the surface of the test body for 15 minutes, and the steel plate back surface temperature Was measured. Each evaluation standard is as follows. The results are shown in Table 1.
(Foaming ratio)
A: Foaming ratio over 35 times A: Foaming ratio over 25 times over 35 times or less B: Foaming ratio over 20 times over 25 times C: Foaming ratio over 15 times over 20 times D: Foaming ratio over 15 times (back surface temperature)
AA: Less than 430 ° C. A: 430 ° C. or more and less than 470 ° C. B: 470 ° C. or more and less than 500 ° C. C: 500 ° C. or more and less than 550 ° C. D: 550 ° C. or more (dense)
The test body for which the expansion ratio was measured was cut, and the denseness of the carbonized heat insulating layer in the cross section was visually confirmed. The evaluation criteria were a four-step evaluation (excellent: A>B>C> D: inferior) where “A” indicates a high density and “D” indicates a low density.

<Heat resistance protection evaluation 2>
(Evaluation of dropout prevention)
The test specimen [I] is placed horizontally so that the coating material is on the lower side, a heater (heater temperature 680 ° C.) is installed at a position 25 mm above the test specimen, and the test specimen is heated by the heater. The steel plate temperature was measured when the coating material dropped out. Evaluation was performed in the following four stages. The results are shown in Table 3.
A: Drop-off temperature 250 ° C. or higher B: Drop-off temperature 220 ° C. or higher and lower than 250 ° C. C: Drop-off temperature 200 ° C. or higher and lower than 220 ° C. D: Drop-off temperature 200 ° C. or lower

  Examples 1 to 7 are excellent in foaming properties and can sufficiently suppress an increase in the back surface temperature. In particular, in Examples 4 to 6, the formed carbonized heat insulating layer is good in denseness, and has sufficient heat resistance protection performance. It was something that could be demonstrated. In Example 8, although it was inferior to Examples 1-7, it showed foamability and had heat-resistant protective performance. On the other hand, Comparative Example 1 was insufficient in foamability and could not obtain heat-resistant protection performance.

(Coating materials 10-15)
Coating materials 10 to 15 were prepared according to the film forming components shown in Table 1 and the formulation shown in Table 3. At this time, the component (a1), the component (B) to the component (I), and additives are mixed by a conventional method to prepare a main agent, and then the component (a2) (curing agent) is mixed and the covering material 10 is mixed. ~ 15 was obtained.

(Examples 9 to 17)
Furthermore, the following evaluation was implemented about the coating materials 4-6 and the coating materials 10-17.

<Heat resistance evaluation 3>
Based on the ISO 5660-1 corn calorimeter method, using an electric heater (CONEIII, manufactured by Toyo Seiki Co., Ltd.), the foaming magnification when radiating heat of 50 kW / m ^{2 to} the surface of the specimen [I] for 30 minutes, and The steel plate back surface temperature was measured. Each evaluation standard is the same as the heat resistance evaluation 1 described above. The results are shown in Table 3.

<Thickening evaluation 1>
A coating material is applied on the entire surface of a steel plate (150 mm long × 70 mm wide × 1.6 mm thick) coated in advance with a rust preventive film with a wet film thickness of 3 mm using a film applicator, 24 hours at room temperature (25 ° C.), and then 50 ° C. For 24 hours, the dry film thickness was measured, and the change in the film thickness was confirmed. The evaluation criteria are as follows. The results are shown in Table 3.
A: Film thickness reduction rate is less than 15% B: Film thickness reduction rate is 15% or more and less than 30% C: Film thickness reduction rate is 30% or more and less than 45% D: Film thickness reduction rate is 45% or more

<Thickening evaluation 2>
In the thickening evaluation 1, the state of the formed film was visually confirmed. The evaluation criteria were a four-step evaluation (excellent: A>B>C> D: inferior), in which “A” was formed with a uniform film and “D” was cracked in the film. The results are shown in Table 3.

Claims (2)

The coating is a coating material that forms a carbonized thermal insulation layer by increasing the temperature,
The coating material includes a polyol component (a1) and a polyisocyanate component (a2) as a film-forming component (A),
The cured coating of the film-forming component (A) has a 10% thermogravimetric decrease temperature in a thermogravimetric method of less than 300 ° C. The coating material according to claim 1, wherein the film-forming component (A) has an isocyanurate ring.