JP2001040290A - Foaming type fireproof coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a foaming type fireproof coating material having a high foaming ratio free from falling off of fireproof coating material layer after foaming. SOLUTION: This coating material comprises (1) a polyhydric alcohol which is arbitrarily selected from pentaerythritol, dipentaerythritol, tripentaerythritol and polypentaerythritol, (2) a nitrogen-containing blowing agent, (3) a synthetic resin, (4) a flame-retardant blowing agent which is ammonium phosphate and/or ammonium polyphosphate in the ratio of the components (1):(2):(3):(4):(5) of 100:80-150:200-500:280-450:100-300 and consequently has excellent fireproof performances free from crack and falling off of fireproof coating material layer after foaming.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a fireproof covering material used for protecting steel materials used for steel columns and beams from fire. The present invention relates to a fire-resistant paint for forming a heat insulating layer. Therefore, the application field is the construction field.

[0002]

2. Description of the Related Art Conventional fire-resistant paints have difficulty in controlling foaming, causing the foamed layer to fall off due to excessive foaming, cracking of the foamed layer due to uneven foaming, and weakness of adhesion of the foamed layer to a steel base. However, due to insufficient strength of the foam layer itself, sufficient fire resistance cannot be exhibited.

[0003]

SUMMARY OF THE INVENTION The present invention realizes the formation of a foam layer which does not easily fall off by controlling foaming in a well-balanced manner, and provides excellent fire resistance performance (for example, JIS A) in a thin film.
In the heating test of 1304 (fire resistance test method for building structural parts), the time required for the back surface temperature of the specimen coated with the refractory paint to a thickness of 2 mm to reach 500 ° C. is 45 minutes or more. ).

[0004]

According to the present invention, there is provided a foamed refractory paint containing a polyhydric alcohol, a nitrogen-containing blowing agent, a synthetic resin, a flame-retardant blowing agent, and titanium oxide as main components. It is arbitrarily selected from pentaerythritol, dipentaerythritol, tripentaerythritol and polypentaerythritol, and the flame-retardant blowing agent is ammonium phosphate and / or ammonium polyphosphate, and in a weight ratio of ::::
Is 100: 80-150: 200-500: 280
450: 100-300.

The individual elements of the present invention will be described below. The one component polyhydric alcohol is dehydrated and condensed with a flame-retardant foaming agent described later, and forms a foamed layer with a decomposition gas of the flame-retardant foaming agent and the nitrogen-containing foaming agent. For example, one or more arbitrarily selected from pentaerythritol, dipentaerythritol, tripentaerythritol, and polypentaerythritol must be used. These four types of substances have a decomposition temperature of 260 ° C., and the same effect can be expected by using any of them.

The two-component nitrogen-containing blowing agent can be arbitrarily used from, for example, dicyandiamide, azodicarbonamide, melamine and derivatives thereof, urea, guanidine, trimethylolmelamine, hexamethylolmelamine and the like. Among these, from the control of two-stage foaming to increase the foaming ratio again at a temperature different from the decomposition temperature of the flame-retardant foaming agent,
Most preferably, melamine and its derivatives having a decomposition temperature of 370 ° C. are used. When the blending amount of the polyhydric alcohol is 100 parts by weight, the blending amount of the nitrogen-containing blowing agent is 80.
Must be ~ 150 parts by weight. When the proportion of the nitrogen-containing blowing agent based on the polyhydric alcohol is less than 80 parts by weight, a sufficient foamed layer cannot be obtained. Conversely, if it exceeds 150 parts by weight, the foamed layer may fall off due to excessive foaming, resulting in poor fire resistance.

[0007] The three-component synthetic resin plays a role of imparting adhesion and weather resistance of the coating film at room temperature. Examples of the synthetic resin include a melamine resin, an acrylic resin, an alkyd resin, a vinyl chloride resin, a vinyl acetate resin, a urethane resin, an epoxy resin, a silicone resin, and a polyester resin. These resins may be used alone or may be copolymerized, and may be used as a mixture. Further, as the form of these resins, both those dissolved in an organic solvent and those dispersed in water as an emulsion can be used.

When the amount of the polyhydric alcohol is 100 parts by weight, the amount of the synthetic resin is 200 to 5 in terms of solid content.
00 parts by weight, preferably 251 to 400 parts by weight. It exhibits the best fire resistance performance in this range. This is because when the synthetic resin layer is softened by heating,
It serves to prevent the generated gas from leaking out. Deviating from this range has little effect on the foaming height of the foamed layer itself, but has a significant effect on the fire resistance performance according to JIS A1304. If the amount is less than 200 parts by weight, the gas for foaming cannot be captured, and the fire resistance is poor. On the other hand, if it exceeds 500 parts by weight, the foaming itself is hindered, and sufficient fire resistance cannot be obtained.

The four-component flame-retardant blowing agent must use ammonium phosphate and / or ammonium polyphosphate.
It is to be noted that a material whose surface is coated with microcapsules with melamine or the like can be used similarly.

The flame-retardant blowing agent is composed of ammonium phosphate and / or ammonium polyphosphate, and when heated, both decompose at 275 ° C. to generate ammonia gas and at the same time lower the material temperature by an endothermic reaction. Further, a flame retardant effect is brought about by bonding with a polyhydric alcohol or a synthetic resin, and a foamed layer having a stitch structure is formed. When the blending amount of the polyhydric alcohol is 100 parts by weight, the blending amount of the flame-retardant blowing agent must be 280 to 450 parts by weight. If the amount is less than 280 parts by weight, sufficient foaming and heat absorption are not performed, and the fire resistance is poor. If the amount exceeds 450 parts by weight, the foamed layer may fall off or crack due to excessive foaming, resulting in poor fire resistance.

The five-component titanium dioxide promotes the bonding of the above-mentioned components when heated by its catalytic action, thereby forming a foam layer having a higher shape retention at a lower temperature. When the amount of the polyhydric alcohol is 100 parts by weight, the amount of the titanium dioxide must be 100 to 300 parts by weight. 10
If the amount is less than 0 parts by weight, the catalytic effect is not sufficient, and it is not different from the usual use for hiding. In addition, since the decomposition temperature of titanium dioxide exceeds 3000 ° C., if it exceeds 300 parts by weight, the residual amount in the foamed layer is too large, resulting in a brittle foamed layer. For this reason, the foamed layer blows off due to the gas pressure at the time of heating, and fire resistance cannot be obtained. JP-A-7-
331124 has an example in which titanium dioxide to a polyhydric alcohol is used in this range, but in this case, melamine is not used. As the titanium dioxide, both rutile type and anatase type can be used. Anatase type is more effective. The first to fifth conditions must be satisfied at the same time.

Part 6 In addition to the above-mentioned main components, the following components conventionally added to the fire-resistant paint are added to the foamed fire-resistant paint of the present invention within a range not to impair the effects of the present invention. As its components, fillers such as calcium carbonate, aluminum hydroxide, alumina, silica, inorganic fibers, rock wool,
Halogen, phosphorus, antimony trioxide and other flame retardants, and defoamers, dispersants, surfactants such as wetting agents,
Components used in ordinary paints, such as film-forming aids, solvents such as antifreezing agents, coloring pigments, extender pigments, metal soaps, stabilizers, thickeners for adjusting viscosity and viscosity, preservatives, and antifungal agents There is.

The foam type refractory paint of the present invention can be applied by a usual paint application method such as brushing or spraying, and can also be applied with a trowel, a roller, or the like.

The foam type refractory paint of the present invention is suitably used not only for steel frames but also for aluminum, zinc-iron plates, asbestos cement plates and the like. It is also useful for making flammable substances such as wood, plywood, paper, fiber, etc. semi-flammable or flame-retardant. Other than that, it is also effective for covering electric cables.

In using the fire-resistant paint of the present invention, it is possible to apply an undercoat by a primer treatment (eg, in the case of steel frame, a rust-proof paint, etc.) and then apply a foamed fire-resistant paint. After applying the foam type refractory paint of the present invention, it is also possible to apply a middle coat and a top coat for the purpose of improving the appearance and durability.

[0016]

With the refractory paint of the present invention, when exposed to a high-temperature flame, the synthetic resin melts and starts to decompose. at the same time,
The polyhydric alcohol is dehydrated and condensed with the flame-retardant blowing agent to form a foamed heat insulating layer having a carbon skeleton under the influence of the decomposition gas of the flame-retardant blowing agent or the nitrogen-containing blowing agent.
Titanium dioxide does not decompose below 1000 ° C.
The polyhydric alcohol, the nitrogen-containing blowing agent, the synthetic resin, and the flame-retardant blowing agent at a temperature of from 300C to 300C act as a catalyst for the decomposition or condensation reaction.

Hereinafter, the formulations of Examples and Comparative Examples are shown, and the fire-resistant paint of the present invention will be described.

[Table 1]

[0018]

[Table 2]

[0019]

[Table 3]

[0020]

[Test method] STKR400 square steel pipe for general structure blasted as specified in JIS G 3466 (3
00 mm x 300 mm x thickness 9 mm) length 1000 mm
Was spray-coated with a foam type refractory paint to a thickness of 2 mm on the square steel pipe, and cured for 21 days to prepare a test body. In applying the refractory paint, each paint was adjusted to have a viscosity of 30 to 35 dPa · s by dilution with water. The test body was subjected to a heating test according to the standard heating curve of JIS A 1304, and the back surface temperature of the steel material was measured with a K thermocouple. The evaluation was performed by observing the time (minute) when the back surface temperature of the steel material reached 500 ° C. and the appearance of the specimen after the completion of heating.

With respect to the appearance of the test piece, the presence or absence of cracks in the foam layer and the falling off of the foam layer were visually confirmed. The cracks in the foam layer are those without any cracks at all: ○, those that have cracks and have a crack width of less than 1 mm ... Δ, those that have a crack width of 1 mm or more… × Means that there is no dropout at all ... ○, less than 20% of the total is dropped ... △, more than 20% of the total is dropped ・
.. × Represent as above.

[0022]

【result】

[Table 4]

[0023]

[Table 5]

[0024]

[Table 6]

[0025]

According to the present invention, it is possible to obtain a foamed refractory paint having excellent refractory performance capable of withstanding a refractory test for 45 minutes or more by coating with a thickness of 2 mm.

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[Procedure amendment]

[Submission date] October 26, 2000 (2000.10.
26)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction contents]

Hereinafter, the formulations of Examples and Comparative Examples are shown, and the fire-resistant paint of the present invention will be described.

[Table 1]

Claims (1)

[Claims] 1. A polyhydric alcohol, a nitrogen-containing blowing agent,
A synthetic resin, a flame-retardant blowing agent, a paint containing titanium dioxide as a main component, wherein the polyhydric alcohol is arbitrarily selected from pentaerythritol, dipentaerythritol, tripentaerythritol, and polypentaerythritol; Ammonium phosphate and / or
Or ammonium polyphosphate, and the weight ratio of :::: is 100: 80 to 150: 20.
0 to 500: 280 to 450: 100 to 300.