JP6917341B2 - Covering material - Google Patents

Description

The present invention relates to a novel coating material.

For the purpose of protecting a base material such as a steel material, concrete, wood, or synthetic resin from a fire, various coating materials that foam due to a temperature rise at the time of a fire to form a carbonized heat insulating layer have been proposed. As such a coating material, a synthetic resin mixed with a foaming agent, a carbonizing agent, a flame retardant, or the like is known. The heat-resistant protection performance of such a coating material is often determined by the coating film thickness, and the heat-resistant protection performance may be significantly affected by the difference in the coating thickness. Therefore, in order to obtain the desired heat-resistant protective performance, it is important to apply the coating so as to have a predetermined coating thickness and uniform, and above all, the selection of the synthetic resin is important.

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

Japanese Unexamined Patent Publication No. 5-70540

However, in the case of Patent Document 1, the expansion ratio of the film when the temperature rises is lower than that of the coating material using an acrylic resin or an epoxy resin as the synthetic resin, and further, the carbonized heat insulating layer (foamed layer) is incinerated or shrunk. Such problems may occur, and there is still room for improvement in order to obtain the desired heat-resistant protective performance.
The present invention has been made in view of such a problem, and an object of the present invention is to provide a coating material capable of forming a stable carbonized heat insulating layer when the temperature rises and ensuring excellent heat resistance protection performance. And.

In order to solve such a problem, the present inventors include a polyol component and a polyisocyanate component as resin components in a coating material whose coating material forms a carbonized heat insulating layer due to a temperature rise in the event of a fire, and specify specific phosphorus. It has been found that the above-mentioned problems can be solved and the heat-resistant protective performance of the base material can be maintained by containing the compound, and the present invention has been completed.

That is, the present invention has the following features.
1. 1. The coating material is a coating material that forms a carbonized heat insulating layer as the temperature rises.
The coating material contains a binder (A) and at least two phosphorus compounds (B).
The binder (A) contains a polyol component (a1) and a polyisocyanate component (a2).
The binder (A) has an exothermic peak in the differential thermal analysis method.
The phosphorus compound (B) has at least one endothermic peak in a temperature region (X) lower than the temperature + 65 ° C., which indicates the maximum value of the exothermic peak of the binder (A) in the differential thermal analysis method. and look-containing phosphorus compound (b2) having at least one endothermic peak in the temperature region (X) higher than the temperature range (Y),
Further, a coating material containing a foaming agent (C) and a carbonizing agent (D).
2. The phosphorus compound (B) is characterized in that it exhibits a weight loss with an endothermic reaction. The covering material described in.
3. 3. 1. The maximum value of the exothermic peak of the binder (A) is in the temperature range of 200 to 400 ° C. Or 2. The covering material described in.
4. The coating material according to any one of claims 1 to 3, further comprising at least one selected from a flame retardant (E) and a filler (F).

The present invention is a coating material whose coating material forms a carbonized heat insulating layer by increasing the temperature, and the coating material contains a polyol component (a1) and a polyisocyanate component (a2) as a binder (A), and further. By containing a specific phosphorus compound (B), it has excellent foaming properties when the temperature rises due to a fire or the like, and suppresses ashing and shrinkage of the carbonized heat insulating layer to form a stable carbonized heat insulating layer. The heat resistance of the material can be improved. INDUSTRIAL APPLICABILITY The present invention can exhibit sufficient heat-resistant protection, particularly when exposed to a high temperature.

It is a figure which shows the exothermic peak of the binder (A) used in this invention. It is a figure which shows the endothermic peak of the phosphorus compound (B) used in this invention. It is a figure which shows the relationship between the exothermic peak of the binder (A) and the endothermic peak of a phosphorus compound (B) used in this invention. It is a figure which shows the endothermic peak of the phosphorus compound (B) used in this invention.

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

The coating material of the present invention forms a carbonized heat insulating layer due to a temperature rise (heating) due to a fire or the like, and the coating material contains a polyol component (a1) and a polyisocyanate as a binder (A). The component (a2) is included as an essential component. The polyol component (a1) and the polyisocyanate component (a2) are components that react to form a film.

The polyol component (a1) of the present invention is not particularly limited, but for example, a polyether polyol, a polyester polyol, an acrylic polyol, an epoxy-containing polyol, a silicone-containing polyol, a fluorine-containing polyol, a castor oil, a castor oil-modified polyol, a polycarbonate polyol, and a poly. Examples thereof include lactone polyols, polybutadiene polyols, polypentadiene polyols, and one or more selected from these can be used.

In the present invention, it is preferable to include a polyether polyol as the polyol component (a1). The molecular weight of the polyether polyol is preferably 1000 or more (more preferably 3000 or more and 20000 or less, further preferably 5000 or more and 18000 or less, particularly preferably 6000 or more and 15000 or less, and most preferably 6500 or more and 12000 or less). By including such a polyol component, the foamability is improved by increasing the temperature of the coating film (preferably the coating film surface temperature is 200 ° C. or higher, more preferably 250 ° C. or higher), and an excellent carbonized heat insulating layer can be formed. This is possible, and the heat-resistant protection performance of the base material can be further enhanced. In the present invention, the molecular weight of the polyol component (a1) is a number average molecular weight (Mn), which is a so-called polystyrene-equivalent molecular weight determined by gel permeation chromatography using a polystyrene polymer as a reference.

The above-mentioned polyether polyol can be obtained by addition polymerization of polyhydric alcohols such as trimethylolpropane, glycerin, hexanetriol, pentaerythritol derivative, sorbitol and neopentyl glycol and alkylene oxides such as ethylene oxide and propylene oxide. It is a thing. 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 end is more preferable. be. Further, the above-mentioned polyether polyol preferably contains a polyether polyol having 3 or more functional groups (3 or more functional groups) having an active hydrogen atom. In this case, the curability is excellent and the film can be stably formed, so that the effect of the present invention can be easily obtained. A hydroxyl group is suitable as the functional group having an active hydrogen atom.

The hydroxyl value of such a polyether polyol is preferably 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 has excellent foamability and can enhance the heat-resistant protection performance of the base material. In the present invention, "α to β" is synonymous with "α or more and β or less".

The content of the polyether polyol is preferably 90% by weight or more (more preferably 95% by weight or more) with respect to the total amount of the polyol component (a1). It is also preferable that the polyol component (a1) is composed only of the above-mentioned polyether polyol.

Examples of the polyisocyanate component (a2) of the present invention include toluene diisocyanate (TDI), 4,4-diphenylmethane diisocyanate (pure-MDI), polypeptide 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, etc.; and these. Examples thereof include blocked isocyanate obtained by blocking diisocyanate with alcohols, phenols, ε-caprolactam, oximes, active methylene compounds and the like, and one or more selected from these can be used.

In the present invention, it is preferable that the polyisocyanate component (a2) contains hexamethylene diisocyanate (HMDI) and / or a derivative thereof (hereinafter, also referred to as “HMDIs”). 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). Further, as the derivative, a biuret form and / or an isocyanurate form is suitable. In such a case, the curability of the formed film is excellent, and when the temperature rises, more excellent foamability can be exhibited, and the heat resistance of the base material can be enhanced.

The mixing of the polyol component (a1) and the polyisocyanate component (a2) is preferably 0.6 to 3.5 (more preferably 1 to 1) in terms of the NCO / OH equivalent ratio of the polyol component (a1) and the polyisocyanate component (a2). The ratio is 2.5, more preferably 1.1 to 1.9). In such a case, it is excellent in curability, a uniform film with a desired thickness can be formed, and when the temperature rises due to a fire or the like, it exhibits more excellent foamability and forms a stable carbonized heat insulating layer. The heat-resistant protection performance of the base material can be improved.

In the present invention, a curing catalyst that promotes the reaction between the polyol component (a1) and the polyisocyanate component (a2) can be used in combination. The curing catalyst is a substance having an action of accelerating the reaction of isocyanate groups to cure. Examples of the curing catalyst include various types such as an amine-based catalyst, an organometallic catalyst, and an inorganic-based catalyst. For example, examples of amine-based catalysts include ethylenediamine, triethylenediamine, triethylamine, ethanolamine, diethanolamine, hexamethylenediamine, derivatives thereof, and mixtures with solvents thereof. Examples of the organometallic catalyst include organometallic compounds such as dibutyltin dilaurate and dibutyltin diacetate; organometallic salts such as potassium acetate, zinc stearate, lead stearate, aluminum stearate, and tin octylate. Examples of the inorganic catalyst include tin chloride and the like. These can be used alone or in combination of two or more, and can also be mixed with a solvent. In the present invention, it is particularly preferable to include an organometallic catalyst. In this case, the curing property of the film-forming component (A) can be enhanced as well as the curing can be promoted, and the effect of the present invention can be enhanced.

The binder (A) of the present invention is characterized by having an exothermic peak in a differential thermal analysis method (DTA method). Specifically, the binder (A) of the present invention has an exothermic peak in a temperature range of, for example, 150 to 800 ° C. (preferably 200 to 600 ° C.). Further, the maximum value of the exothermic peak is preferably in the temperature range of 200 to 400 ° C. (more preferably 250 to 350 ° C.). Further, the binder (A) preferably shows a weight loss in the thermogravimetric analysis method (TG method). Here, the weight loss means that the weight is reduced when the temperature is raised from 150 ° C. to 800 ° C. (the weight at 800 ° C. is smaller than the weight at 150 ° C.).
In the present invention, the differential thermal analysis method and the thermogravimetric analysis method of the binder (A) are measured by using the cured film of the polyol component (a1) and the polyisocyanate component (a2) as a sample. The differential thermal analysis method and the thermogravimetric analysis method are performed by a differential thermal analyzer (for example, "differential thermal balance Thermo".
It was measured using "plus EVO2 TG-DTA series" manufactured by Rigaku, etc.), and 3 ± 1 mg of the sample was taken in a platinum sample pan, α-alumina was used as the standard substance, and the heating rate was 20 ° C./. It was measured by changing the temperature from 100 to 900 ° C. in minutes.

As the phosphorus compound (B) of the present invention, a component that generates a nonflammable gas in the event of a fire can be used. Such a phosphorus compound (B) has a role of forming a carbonized heat insulating layer while imparting flame retardancy to the carbonized film. In particular, as the phosphorus compound (B) of the present invention, the phosphorus compound (b1) having at least one endothermic peak in a temperature region (X) lower than the temperature + 65 ° C. showing the maximum value of the exothermic peak of the binder (A). , And a phosphorus compound (b2) having at least one endothermic peak in a temperature region (Y) higher than the temperature region (X). As described above, in the present invention, the phosphorus compound (b1) has an endothermic peak near the exothermic peak of the binder (A), and the phosphorus compound (b2) has an endothermic peak on the high temperature side thereof, so that stable carbonization occurs when the temperature rises. A heat insulating layer can be formed, and excellent heat resistant protection performance can be ensured.

The mechanism of action is not limited to this, but the phosphorus compound (b1) generates a nonflammable gas and expands itself during the decomposition reaction of the binder (A), and the binder (A). ) Can be suppressed while forming a carbonized heat insulating layer. On the other hand, the phosphorus compound (b2) can suppress the decomposition of the carbonized heat insulating layer of the binder (A) formed by the action of the phosphorus compound (b1), and can further form the carbonized heat insulating layer. As a result, in the present invention, it is possible to suppress ashing and shrinkage of the carbonized heat insulating layer to form a stable carbonized heat insulating layer and enhance the heat resistance of the base material, especially when exposed to a high temperature. , It is presumed that sufficient heat resistance can be exhibited.

Here, the exothermic peak of the binder (A) and the endothermic peak of the phosphorus compound (B) in the present invention will be specifically described. The exothermic peak of the binder in the present invention (A), as shown in FIG. 1, the exothermic peak starting temperature _{[T A1],} the temperature showing the maximum value _{[T A-Max],} the exothermic peak end temperature _{[T A2} a peak _{(S a)} in the temperature region up. Further, in the present invention, the endothermic peak of the phosphorus compound (B) is, as shown in FIG. 2, from the endothermic peak start temperature [ _TB1 ] to the temperature [TB _-Min ] indicating the minimum value, and the endothermic peak end temperature [ a peak _{(S B)} in the temperature range up to T _B2]. (Hereinafter, each temperature of the exothermic peak of the binder (A) is simply [ _TA1 ], [TA _-Max ], [ _TA2 ], and each temperature of the endothermic peak of the phosphorus compound (B) is simply [ _{TB1]. ], [T B-Min]} , also referred to as _{[T B2].)}

Next, FIG. 3 shows the relationship between the exothermic peak of the binder (A) and the endothermic peak of the phosphorus compound (B) in the present invention. The phosphorus compound (b1) of the present invention has at least one endothermic peak in a temperature region (X) lower than _{[TA-Max] + 65 ° C. (preferably + 60 ° C.) of the binder (A).} Moreover, phosphorus compounds (b1) preferably has at least one _{[T B-Min]} to the temperature region (X), binder (A) from _{[T A1], [T A} -Max] +65 It is more preferable to have at least one [TB _-Min ] in the temperature range ( _{AX) up to ° C.} Further, the phosphorus compound (b1) _{preferably has [TB1} ] in a low temperature region rather than _{[TA-Max] of the binder (A).} Further, _{the absolute value of the difference between [TA-Max} ] and [TB _-Min ] is preferably 65 ° C. or lower (more preferably 60 ° C. or lower, still more preferably 55 ° C. or lower. As described above, the binder. so as to overlap the temperature range of the exothermic peak (S _a) of (a), by a phosphorus compound (b1) has an endothermic peak (S _B), when the temperature rises, it is possible to form a stable carbide heat insulating layer In such a case, the above-mentioned effect can be sufficiently exhibited. As such a phosphorus compound (b1), for example, ammonium polyphosphate and the like are suitable.

On the other hand, the phosphorus compound (b2) has at least one endothermic peak in the temperature region (Y) higher than the temperature region (X) in the binder (A). Further, the phosphorus compound (b2) _{preferably has at least one [TB-Min} ] in the temperature region (Y), and further, in the temperature region on the higher temperature side than _[TA2 ] of the binder (A). It is more preferable to have at least one [TB _-Min]. Further, the phosphorus compound (b2) _{preferably has [TB1} ] in a high temperature region rather than _{[TA2] of the binder (A).} Further, _{the absolute value of the difference between [TA-Max} ] and [TB _-Min ] is preferably more than 65 ° C. and 200 ° C. or lower (more preferably 70 ° C. or higher and 150 ° C. or lower). Thus, by the phosphorus compound to the high temperature side of the exothermic peak (S _A) of the binder (A) (b2) has an endothermic peak (S _B), it can be sufficiently exhibited the effect. Specifically, the phosphorus compound (b2) includes, for example, melamine polyphosphate, melam polyphosphate, melamine polyphosphate / melam / melem double salt, or a composite compound of melamine polyphosphate / melam / melem compound salt and dimerum pyrosulfate. , Etc. are suitable. These can be used alone or in combination of two or more.

_{Further, the temperature difference between [TB-min} ] of the phosphorus compound (b2) and [TB _-min ] of the phosphorus compound (b1) {(b2) [TB _-min ]-(b1) [ TB _-min ]} is preferably 40 ° C. or higher (more preferably 50 ° C. or higher). Thereby, the heat resistance protection performance can be further improved.

In the present invention, when the endothermic peak of the phosphorus compound (B) straddles the temperature regions (X) and (Y) as shown in FIG. 4, it has [TB _-min ] in the temperature region (X). A phosphorus compound (b1) is used, and a phosphorus compound (b2) has _{[TB-min] in the temperature range (Y).} Further, in the present invention, a phosphorus compound (B) having two or more endothermic peaks can also be used, and when the temperature regions (X) and (Y) each have [TB _-min ], the phosphorus compound (B) has [TB-min]. _[TB-min ] in the temperature region (X) is defined as the main endothermic peak, and is designated as the phosphorus compound (b1).

Further, it is preferable that the phosphorus compound (B) of the present invention exhibits a weight loss together with an endothermic reaction. Specifically, it is preferable to show weight loss in the temperature range ([ _TB1 ] to [ _{TB2]) having the endothermic peak.} As a result, shrinkage and ashing of the foamed carbonized layer can be further suppressed. Here, the weight loss means that when the temperature is raised from 150 ° C. to 800 ° C., the weight is reduced at least in the temperature range of _[TB1 ] to [ _TB2 ] (the weight in _{[TB2] is [TB2]. The weight in TB1} ] is smaller than that).

The content of the phosphorus compound (B) is based on 100 parts by weight of the solid content of the binder (A).
The phosphorus compound (b1) is preferably 100 to 1000 parts by weight (more preferably 200 to 800 parts by weight, further preferably 250 to 500 parts by weight), and the phosphorus compound (b2) is preferably 5 to 300 parts by weight (more preferably). It is preferably 10 to 200 parts by weight, more preferably 15 to 150 parts by weight). In such a case, the above effect can be fully exerted.

The mixing ratio (weight ratio) of the phosphorus compound (b1) and the phosphorus compound (b2) is preferably (b1) :( b2) = 99: 1 to 50:50 (more preferably 98: 2 to 60). : 40, more preferably 95: 5 to 70:30). In such a case, it has excellent foamability and can suppress ashing and shrinkage of the carbonized heat insulating layer, and the effect of the present invention can be further enhanced.

Further, as the coating material of the present invention, for example, a foaming agent (C), a carbonizing agent (D), a flame retardant (E), a filler (F) and the like can be used.

The foaming agent (C) excludes the phosphorus compound (B), and examples thereof include melamine, dicyandiamide and its derivatives, azobistetrasome and its derivatives, azodicarbonamide, urea, and thiourea. .. These can be used alone or in combination of two or more. The content of the foaming agent (C) 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 binder (A). The foaming agent (C) of the present invention imparts a foaming action to the coating film due to a temperature rise in the event of a fire or the like. Specifically, when the temperature of the coating film surface is preferably 200 ° C. or higher. It imparts a foaming action.

Examples of the carbonizing agent (D) include pentaerythritol, dipentaerythritol, trimethylolpropane, starch, casein and the like. These can be used alone or in combination of two or more. In the present invention, pentaerythritol and dipentaerythritol are particularly preferable because they are excellent in dehydration cooling effect and carbonized heat insulating layer forming effect. The content of the carbonizing agent (D) 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 binder (A). The carbonizing agent (D) of the present invention imparts an action of forming a carbonized heat insulating layer by dehydrating and carbonizing the binder (A) together with carbonization due to a temperature rise in the event of a fire or the like.

The flame retardant (E) excludes the phosphorus compound (B). For example, chlorinated polyphenyl, chlorinated polyethylene, diphenyl chloride, triphenyl chloride, chlorinated paraffin, pentachloride fatty acid ester, and perchloropenta. Chlorinated compounds such as cyclodecane, chlorinated naphthalene and tetrachlorophthalic anhydride; antimony compounds such as antimony trioxide and antimony trichloride; and other inorganic compounds such as zinc borate and sodium borate can be mentioned. These can be used alone or in combination of two or more . The content of the flame retardant (E) is preferably 1 to 500 parts by weight (more preferably 5 to 300 parts by weight) with respect to 100 parts by weight of the solid content of the binder (A).

Examples of the filler (F) include talc, calcium carbonate, sodium carbonate, aluminum oxide (alumina), titanium oxide, zinc oxide, silica, clay, clay, silas, mica, silica sand, silica stone powder, quartz powder, and barium sulfate. And so on. These can be used alone or in combination of two or more. The content of the filler (F) 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 binder (A).

Further, in the present invention, a metal hydrate (G) can be contained in addition to the above components. The metal hydrate (G) exhibits endothermic properties due to a dehydration reaction or the like when the temperature rises, and is different from the filler (F). Examples of such a metal hydrate (G) 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 (G) is preferably 0.1 to 20 μm (more preferably 0.2 to 15 μm, further preferably 0.3 to 8 μm, and most preferably 0.4 to 3 μm). Is. The content of the metal hydrate (G) is preferably 1 to 200 parts by weight (more preferably 5 to 100 parts by weight, still more preferably 8 to 8 to 100 parts by weight) with respect to 100 parts by weight of the solid content of the binder (A). 80 parts by weight).

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

In addition, the additive may be any additive that does not significantly impair the effects of the present invention, for example, pigments, fibers, wetting agents, plasticizers, lubricants, preservatives, fungicides, algae-proofing agents, antibacterial agents, and diluents. Examples thereof include thickeners, leveling agents, dispersants, antifoaming agents, cross-linking agents, silane coupling agents, ultraviolet absorbers, antioxidants, halogen trapping agents, diluting solvents and the like.

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

The coating material of the present invention is preferably a two-component 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 phosphorus compound (B), the foaming agent (C), the carbonizing agent (D), the flame retardant (E), and the filler (F) (furthermore, the metal hydrate (G), The curing catalyst) may be mixed with at least one of the main agent and the curing agent, respectively, but in the present invention, it is preferable to mix with the main agent. In addition, each component can be added when the main agent and the curing agent are mixed.

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, and doors. Applicable base materials include, for example, concrete, mortar, siding board, extruded board, gypsum board, pearlite board, brick, plastic, wood, metal, steel frame (steel material), glass, porcelain tile and the like. These base materials may be those on which a film has already been formed, those on which some kind of base treatment (rust prevention treatment, flame retardant treatment, etc.) has been applied, those on which wallpaper is attached, and the like.

When the coating material of the present invention is applied to a base material, for example, a coating tool such as a spray, a roller, a brush, or a trowel may be used to apply the coating material in one or several steps. It is preferable to apply the coating so that the dry film thickness per step is preferably 400 μm or more (more preferably 500 to 5000 μm). As a result, a thick film can be formed with a small number of coating steps. The film thickness to be finally formed may be appropriately set according to the desired functionality, application site, etc., but is preferably about 0.4 to 5 mm.

In the present invention, in order to protect the coating film formed by the above-mentioned coating material, a topcoat material may be further applied if necessary. Such a topcoat material can be formed by applying a known coating material. As the topcoat material, for example, a coating material such as an acrylic resin-based material, a urethane resin-based material, an acrylic silicon resin-based material, or a fluororesin-based material can be used. The topcoat material may be applied by a known application method, and for example, a coating tool such as a spray, a roller, or a brush can be used.

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

<Binder (A1 to A3)>
The components (a1) and (a2) mixed with the polyol component and the polyisocyanate component (NCO / OH equivalent ratio = 1.2) shown in Table 1 were designated as binders (A1) to (A3).
The cured coatings of the binders (A1) to (A3) were measured (150 to 800 ° C.) by a differential thermal analysis method and a thermogravimetric analysis method. Table 1 shows the results of the differential thermal analysis method. Moreover, as a result of the thermogravimetric analysis method, the weight was reduced in the range of 150 ° C. to 800 ° C. The following raw materials were used.

・ Binder (A)
・ Polyol component (a1)
(A1-1): Polyether polyol (polymer of ethylene oxide and propylene oxide using glycerin as an initiator, number average molecular weight 7000, number of functional groups 3, hydroxyl value 24 mgKOH / g, addition of terminal ethylene oxide)
(A1-2): Polyether polyol (polymer of ethylene oxide and propylene oxide using glycerin as an initiator, number average molecular weight 5100, number of functional groups 3, hydroxyl value 33 mgKOH / g, addition of terminal ethylene oxide)
(A1-3): Polyether polyol (polymer with propylene oxide using glycerin as an initiator, number average molecular weight 700, number of functional groups 3, hydroxyl value 225 mgKOH / g, addition of terminal propylene oxide)
-Polyisocyanate component (a2)
(A2-1) Biuret-type hexamethylene diisocyanate

-Phosphorus compound (B)
_(B1 ): Each temperature of the first endothermic peak of ammonium polyphosphate [TB1] / [TB _-Min ] / [ _TB2 ] = 275 ° C./327 ° C./345 ° C.
Each temperature of the second endothermic peak [ _TB1 ] / [TB _-Min ] / [ _TB2 ] = 345 ° C / 370 ° C / 450 ° C
(B2): Each temperature of the first endothermic peak of the double salt of melamine polyphosphate, melamine, and melem [ _TB1 ] / [TB _-Min ] / [ _TB2 ] = 365 ° C./395 ° C./420 ° C.
All of the above phosphorus compounds show weight loss in the temperature range of _[TB1 ] to [ _TB2].

・ Foaming agent (C): Melamine ・ Carbonized agent (D): Dipentaerythritol ・ Filling agent ( F ): Titanium oxide ・ Metal hydrate ( G ): Aluminum hydroxide (average particle size: 1 μm)
・ Curing catalyst : Organic metal catalyst ・ Additive 1: Dispersant, defoamer, etc. ・ Additive 2: Plasticizer, diluting solvent

(Manufacturing method of covering material)
The dressings 1 to 11 were adjusted according to the binders shown in Table 1 and the formulations shown in Table 2. At this time, the component (a1), the components (B) to (G), and the additive are mixed by a conventional method to prepare a main agent, and then the component (a2) (curing agent) is mixed to prepare a coating material. 1 to 11 were obtained.

(Examples 1 to 8 and Comparative Examples 1 to 3)
A coating material was spray-coated (dry film thickness 1.5 mm) on the entire surface of a pre-rust-prevented steel sheet (length 150 mm x width 70 mm x thickness 1.6 mm) and cured at room temperature (25 ° C.) for 7 days. The following evaluations were carried out using the test specimens.
<Evaluation of curability>
The curability (presence or absence of tack) of the formed film was evaluated by a touch test. The evaluation criteria are as follows.
A: No tack and good curability B: Slightly residual tack C: Slightly residual tack D: Poor curing

<Heat resistance evaluation 1>
^{Based on the ISO 5660-1 cone calorimeter method, the foaming ratio when radiant heat of 50 kW / m 2} is radiated to the surface of the test piece for 15 minutes using an electric heater (CONEIII, manufactured by Toyo Seiki Co., Ltd.), and the temperature of the back surface of the steel sheet. Was measured. Each evaluation standard is as follows. The results are shown in Table 1.
(Effervescence magnification)
AA: Foaming ratio over 35 times A: Foaming ratio over 25 times over 35 times B: Foaming ratio over 20 times over 25 times C: Foaming ratio over 15 times over 20 times D: Foaming ratio 15 times or less (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: More than 550 ° C

<Heat resistance evaluation 2>
^{Based on the ISO 5660-1 cone calorimeter method, the foaming ratio when radiant heat of 50 kW / m 2} is radiated to the surface of the test piece for 30 minutes using an electric heater (CONEIII, manufactured by Toyo Seiki Co., Ltd.), and the temperature of the back surface of the steel sheet. Was measured, and the denseness and incineration property were further evaluated. The evaluation criteria for the foaming ratio and the temperature on the back surface of the steel sheet are the same as those for the heat resistance evaluation 1. The criteria for evaluating the density and incineration are as follows. The results are shown in Table 1.

(Evaluation of precision)
The test piece whose foaming 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 four-grade evaluation (excellent: A>B>C> D: inferior), with high precision being "A" and low precision being "D".
(Evaluation of incineration)
In the above heat resistance evaluation 2, the cross section of the carbonized heat insulating layer formed after radiating radiant heat for 30 minutes was confirmed, and the ratio of the ashed (white) portion was calculated. The evaluation criteria were a four-stage evaluation (excellent: A>B>C> D: inferior), with less ashing being "A" and more ashing being "D".

In Examples 1 to 8, in both the heat resistance evaluation 1 and the heat resistance evaluation 2 (under a high temperature in which the heating test is extended), the foaming property is excellent, a carbonized heat insulating layer is stably formed, and further, the carbonized heat insulating layer is formed. It was possible to suppress the shrinkage of, and it was possible to exhibit sufficient heat resistance protection performance. In particular, in Examples 1 to 3 and 6 and 7, when the heating test is extended, the shrinkage of the carbonized heat insulating layer is sufficiently suppressed (the change in the foaming ratio is small), and even more excellent heat protection performance is exhibited. It was possible. On the other hand, in Comparative Examples 1 and 2, sufficient results were not obtained when the heating test was extended.

Claims (4)

The coating material is a coating material that forms a carbonized heat insulating layer as the temperature rises.
The coating material contains a binder (A) and at least two phosphorus compounds (B).
The binder (A) contains a polyol component (a1) and a polyisocyanate component (a2).
The binder (A) has an exothermic peak in the differential thermal analysis method.
The phosphorus compound (B) has at least one endothermic peak in a temperature region (X) lower than the temperature + 65 ° C., which indicates the maximum value of the exothermic peak of the binder (A) in the differential thermal analysis method. and look-containing phosphorus compound (b2) having at least one endothermic peak in the temperature region (X) higher than the temperature range (Y),
Further, a coating material containing a foaming agent (C) and a carbonizing agent (D). The coating material according to claim 1, wherein the phosphorus compound (B) exhibits a weight loss with an endothermic reaction. The coating material according to claim 1 or 2, wherein the maximum value of the exothermic peak of the binder (A) is in the temperature range of 200 to 400 ° C. The coating material according to any one of claims 1 to 3, further comprising at least one selected from a flame retardant (E) and a filler (F).

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