JPH06100384A - Pollution-free refractory coating composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition resistant to cracking in heating and having excellent light-weight and applicability by using a skeleton obtained by compounding a hydraulic cement, a specific light-weight aggregate, an endothermic substance, a non-pollution fiber and a thickener having low thickening property at specific ratios. CONSTITUTION:The skeleton of the composition is composed of (A) 10-40wt.% of a hydraulic cement, (B) 6-40wt.% of a lightweight inorganic aggregate having particle diameter of <=2mm and consisting of >=50wt.% of closed cell aggregate such as sirasu balloon and <=50wt.% of open cell aggregate such as fired vermiculite, (C) 25-75wt.% of endothermic substance having an average particle diameter of <=10mum and exhibiting heat-absorption peak at 50-500 deg.C on a differential thermal curve determined by differential thermal analysis and heat-absorption of >=300cal/g in thermal decomposition, (D) 0.1-3wt.% of non-pollution fiber having a fiber length of 2-20mm (e.g. chopped strand of carbon fiber or Vinylon fiber) and (E) 1-10wt.% of a thickener having low thickening property to give a 2% aqueous solution having a viscosity of <=1,000cps measured by BM viscometer (30rpm) at 20 deg.C and composed of a synthetic polymer (e.g. methyl cellulose) or a natural polymer (e.g. guar gum). The composition may be further compounded with prescribed amounts of soft coagulation agent and frothing agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to fireproof coating compositions for buildings. Therefore, utilization is in the field of construction.

[0002]

2. Description of the Related Art In recent years, steel-framed buildings have been increasing in number rather than RC structures in terms of shortening construction period and lack of craftsmen in building buildings. The steel frame of this steel structure must be provided with a predetermined fireproof coating to prevent the collapse of the building by keeping the temperature rise at the time of fire within a certain limit. In Japan, asbestos was sprayed before 1975, but after 1975, rock was used due to health problems caused by handling asbestos, environmental pollution due to scattering of asbestos, and harm to the human body. Wool is being sprayed. Although the blowing of rock wool is excellent in terms of economical efficiency, it has recently been shunned due to the fact that the work environment is poor due to the scattering of rock wool fibers, the appearance is not beautiful, and the surface strength is weak.

Further, there is a fireproof coating material other than the above which uses water glass as a binder, but it has a problem in water resistance or weather resistance and is not practical.

As an improvement to these, Japanese Patent Laid-Open No. 61-61
There is a fire resistant coating material in which a hydraulic cement, a lightweight aggregate and a substance having a high degree of hydration are combined in a specific ratio as disclosed in Japanese Patent No. 776887.

Further, to improve these, hydraulic cement, lightweight aggregate, endothermic substance, water-soluble resin, and synthetic resin-based admixture as disclosed in JP-A-2-311379 are used in a specific ratio. There are combined fire resistant coatings.

[0006]

However, the refractory coating material disclosed in the above-mentioned JP-A-61-77787 is easily cracked by drying shrinkage after curing, or is weak against cracking during heating, and peels off. It was easy. In addition, asbestos, glass fiber, other components shown in the detailed description,
In the case of using rock wool fiber or the like, it is not practical because it is pierced into the skin and causes inflammation, and especially asbestos causes a disease in the lungs and the like, which is dangerous. Further, the fire-resistant coating material disclosed in Japanese Patent Application Laid-Open No. 2-311379 has a risk that the endothermic substance is not defined and its effect is insufficient, or that it is vulnerable to cracking during heating and easily peels off to impair the fire resistance performance. was there. This invention seeks to solve problems such as poor working environment, lack of durability, lack of finish aesthetics, lack of efficient fire resistance, and lack of total economy in conventional fireproof coatings in the construction field. It is a thing.

[0007]

The composition of the present invention comprises 10-40% by weight of hydraulic cement as a skeleton, 6-40% by weight of an inorganic lightweight aggregate, 25-75% by weight of an endothermic substance, and pollution-free fiber. 0.1 to 3% by weight, low thickening thickener 1 to 10
It is composed by weight percent. Further, the skeleton further contains a soft coagulant in an amount of 0.1 to 10% by weight.
In addition, the foaming agent is further added in an amount of 0.01 to 3% by weight. The composition has hydraulic properties by hydraulic cement, heat insulation and weight reduction of the covering material by the inorganic lightweight aggregate, and by specifying the endothermic substance, the stability of the fire resistance performance and the further improvement of the fire resistance performance are achieved, The fire-resistant coating material is made of pollution-free fibers and is safe and resistant to cracking, and the low-viscosity thickening agent is used as a fire-resistant coating material that improves pumpability and adhesion to the body at the same time. In addition, the soft coagulant is used to increase the spraying thickness per time, improving workability. In addition, a foaming agent is used to reduce the weight and cost, making it a more practical fireproof coating in total.

The composition of the present invention is described in detail below.
First of all, hydraulic cement is white Portland cement,
Various Portland cements specified by JIS-R-5210, Various blast furnace cements specified by JIS-R-5211,
Various silica cements specified in JIS-R-5212, J
It is either a mixed cement such as various fly ash cements specified by IS-R-5213, an alumina cement, or a combination thereof. The hydraulic cement acts as a binder for the fire resistant coating composition. The amount of such hydraulic cement used is in the range of 10 to 40% by weight. When the amount of this hydraulic cement used is less than 10% by weight, the strength of the fire-resistant coating composition becomes weak, and when it exceeds 40% by weight, the strength becomes unnecessarily large and cracks easily due to thermal strain during heating.

Next, as the inorganic lightweight aggregate, natural or industrially produced shirasu as a closed-cell inorganic lightweight aggregate, glass scrap, and shirasu balloon which is made into a hollow foam by heating obsidian, glass There are balloons, obsidian perlite, etc., and naturally-occurring pearlite as an open-celled inorganic lightweight aggregate, pearlite perlite made into a continuous foam by heat-processing mica-like minerals, and calcined hirucite . The composition of these inorganic lightweight aggregates with noncombustibility is
It is preferable that the closed-cell inorganic lightweight aggregate is 50 wt% or more, and the open-cell inorganic lightweight aggregate is 50 wt% or less. With such a structure, it is possible to maintain excellent fire resistance and also have excellent pumping and pumping properties due to the bearing effect of the closed-cell inorganic lightweight aggregate. When the content of the open-celled inorganic lightweight aggregate exceeds 50% by weight, pumpability and fire resistance are slightly deteriorated. Further, the particle size of the inorganic lightweight aggregate is preferably 2 mm or less. Particles having a particle size of more than 2 mm are not preferable for forming a dense heat insulating layer. The apparent bulk specific gravity is preferably 0.4 or less. The amount of the inorganic lightweight aggregate used is 6 to 40% by weight. The amount of inorganic lightweight aggregate used is 6
If it is less than 10% by weight, it is not suitable as a fireproof coating material because it is not lightweight, and if it exceeds 40% by weight, the cost is high and the fireproofing performance is somewhat insufficient.

The term "endothermic substance" as used in the present invention means that the endothermic peak of the differential thermal curve in differential thermal analysis is 50 ° C to 5 ° C.
It is in the range of 00 ° C., and the endothermic amount in the thermal decomposition is 300 cal / g or more in the standard state conversion. Examples of this include aluminum fluoride, aluminum hydroxide, dibasic calcium phosphate, calcium oxalate, cobalt hydroxide,
Examples include borax, magnesium hydroxide, and cobalt chloride ammonia complex. The endothermic substance is specified to have an average particle size of 10 μm or less. By using this specified endothermic substance, the particle size of 15
~ 300μ aluminum hydroxide and decomposition temperature is 850 ℃
Substantially more effective in fireproof coating performance than calcium carbonate. Here, the endothermic peak of the endothermic substance is 50
The limits of the range of ℃ ~ 500 ℃, steel columns,
In the fire resistance test of the beam, the average temperature of the steel material is required to be 350 ° C or less, and the combustion temperature in case of fire is about 1,
This is because the rate of decomposition becomes substantially larger as the temperature difference from 000 ° C. becomes larger. In the present invention, an effective endothermic substance was sought with the goal of fire resistance of 20 mm or less for 1 hour, fire resistance of 30 mm or less for 2 hours, and fire resistance of 40 mm or less for 3 hours. This will be described with reference to FIGS. FIG. 1 is a diagram showing a temperature gradient between the maximum furnace temperature in the 1-hour fireproof heating test and the steel material temperature that passes the fireproof test.
3 is a diagram showing a temperature gradient in the case of the 2-hour fire resistance test, and FIG. 3 is a diagram showing a temperature gradient in the case of the 3-hour fire resistance test. α represents a ratio of a substance that thermally decomposes and absorbs at 500 ° C. to contribute to the heat absorption in the refractory coating layer. α is calculated by the following formula 1,
In the formula, x is the thickness of the refractory coating layer, and y is the thickness from the surface of the steel material where the temperature is 500 ° C.

[0011]

[Formula 1]

In the case where the coating thickness of 20 mm in FIG. 1 has a fireproof performance for 1 hour, the endothermic substance which decomposes at 500 ° C. or lower may be decomposed with a high efficiency of decomposition efficiency α = 75% or more. . In the case where the coating thickness of 30 mm in FIG. 2 has a fireproof property for 2 hours, the endothermic substance that decomposes at 500 ° C. or lower may be decomposed with high efficiency of decomposition efficiency α = 77% or more. When the coating thickness of 40 mm shown in FIG. 3 is given a fireproof performance for 3 hours, an endothermic substance that decomposes at 500 ° C. or lower has a possibility of being decomposed with high efficiency of decomposition efficiency α = 79% or more.
It is considered that what is decomposed here contributes to heat absorption and can suppress the temperature rise of the steel material. Further, those having a thermal decomposition temperature of less than 50 ° C. are practically unstable and cannot be used. Further, if the temperature exceeds 500 ° C., the ratio capable of contributing to thermal decomposition is low, which is not preferable. Further, the efficiency of thermal decomposition can be made more complete by selecting the average particle size as small as 10 μm or less. If the average particle size exceeds 10 μ, the efficiency of thermal decomposition decreases. In addition, the endothermic amount per unit mass of the endothermic substance is 3
This is because those having a calorific value of 00 cal / g or more have a large force for suppressing the temperature rise of the steel material and the coating material and synergistically enhance the substantially fire-resistant coating performance. Further, the endothermic amount of the endothermic substance is 300 ca.
If it is less than 1 / g, the performance is insufficient. The amount of the endothermic substance used is effective when used in the range of 25 to 75% by weight. If the amount of the endothermic substance used is less than 25% by weight, the fire resistance becomes poor and the coating thickness must be increased. On the other hand, if it is more than 75% by weight, the mixing ratio of the hydraulic cement becomes relatively small and the bonding strength becomes insufficient.

The pollution-free fiber referred to in the present invention is a chopped strand processed fiber having a fiber length of 2 to 2.
The range is 20 mm and the compounding amount is 0.1 to 3% by weight. The material of the fiber is one or more selected from carbon fiber, vinylon fiber, aramid fiber and nylon fiber. The chopped strand processing and the selection of the material are harmless. Compounding amount is 0.1
If it is less than 5% by weight, it easily cracks and the fire resistance becomes insufficient, resulting in 3
When it exceeds the weight%, the spraying workability is deteriorated and it is not necessary.

The low-viscosity thickening agent means a methylcellulose whose 2% aqueous solution has a viscosity of 1,000 cps or less when measured at a solution temperature of 20 ° C. and a BM type viscometer at 30 rpm. Synthetic polymeric thickeners such as polyvinyl alcohol and hydroxyethyl cellulose, or natural polymeric thickeners such as guar gum and alginic acid derivatives, or a combination thereof.
Effective when set to 0% by weight. Here, the use of a low thickening thickener is particularly advantageous because it does not become extremely sticky and does not hinder the use even if the usage ratio is increased compared to the high thickening thickener. This is because it is possible to improve the bubble entrainment property, improve the pump pressure feeding property, and increase the adhesion strength. If the compounding amount is less than 1% by weight, the compounding effect is small, and if the compounding amount exceeds 10% by weight, the fire resistance performance is deteriorated.

The pollution-free, fire-resistant coating composition of the present invention has a general formula M ₂ O.nSiO ₂ as a soft coagulant so that the spray coating thickness per time can be increased.
(However, M is an alkali metal, n is a number of 1.5 to 7.0), or a silicate compound or colloidal silica is contained or used alone or in a mixture. The effect is obtained when the content or the amount used is 0.1 to 10% by weight. When the amount used is less than 0.1% by weight, the coagulation effect is small,
You cannot increase the thickness of each spray coating. Also,
Exceeding 10% by weight is not necessary for this purpose.

Further, the foaming agent used in the present invention means that the foaming force is 20 mm immediately after the condition of using a 0.1% aqueous solution of the foaming agent in the measurement of the foaming force under a predetermined condition.
Either or a mixture of nonionic, nonionic / anionic, anionic, and zwitterionic activators, which is 75% or more of the value immediately after the above and after 5 minutes.

As a nonionic foaming agent, HLB (Hy
drophile-lipophile balance) in the range of 9 to 20 polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene oleyl ether, polyoxyethylene Lauryl ether, polyoxyethylene oleyl ether, polyoxyethylene oleic acid ester, polyoxyethylene sorbitan monolaurate, polyoxyethylene lanolin alcohol ether, polyoxyethylene lanolin fatty acid ester, alkylalkylolamide, lauric acid diethanolamide, coconut oil Fatty acid mono (or di) ethanolamide, oleic acid diethanolamide, lauric acid isopropanolamide, stearic acid monoe Noruamido, and the like as polyoxyethylene coconut oil fatty acid amide.

Polyoxyethylene alkyl (or alkylallyl) as a nonionic / anionic foaming agent
There are ether phosphates.

As the anionic foaming agent, polyoxyethylene sodium lauryl sulfate, polyoxyethylene lauryl sulfate triethanolamine, polyoxyethylene alkyl ether sulfate triethanolamine, sodium alkyl sulfate, sodium alkyl ether sulfate,
Sodium lauryl ether sodium sulfate, alkylethanol triethanolamine, fatty acid soda (potassium) soap,
Castor Potassium Soap, Sodium Lauryl Sulfate, Triethanolamine Lauryl Sulfate, Ammonium Lauryl Sulfate, Sodium 2-Ethylhexyl Alkyl Sulfate, Sodium Acylmethyl Taurate, Sodium Lauroyl Methyl Taurate, Sodium Dialkylsulfosuccinate, Sodium Dovanol Ethoxysulfate, N coconut oil fatty acid acyl L sodium glutamate and the like.

As a foaming agent for zwitterions, 2 undecyl N carboxymethyl N hydroxyethyl imidazolinium betaine, 2 alkyl N carboxymethyl N hydroxyethyl imidazolinium betaine, lauryl carboxymethyl hydroxyethyl imidazolinium betaine, lauryl Amino propionate and the like.

These are used in an amount of 0.01 to 3% by weight. In particular, in order to obtain long-term stability of the foam, the foam stability is measured by the loss miles method, which is an index of foam stability. It is desirable to use a foaming agent whose value after 5 minutes is 75% or more of the value of the foaming force immediately after.

In addition to the above, auxiliary blast furnace slag, ceramics waste powder, gypsum, dolomite plaster, kaolin, clay,
It is also possible to use clay, diatomaceous earth, talc, bentonite, barium sulfate, alumina, etc. for the purpose of increasing the amount.
Also, titanium oxide, red iron oxide, oak, phthalocyanine blue, phthalocyanine green, carbon black,
It is also possible to enhance the design by coloring with various color pigments such as. Further, a rust preventive agent can be added if necessary. These auxiliary additives are used by replacing hydraulic cement, inorganic lightweight aggregate or specified endothermic substance within the range not impairing the purpose of the present application.

The composition of the present invention is kneaded and stirred with an appropriate amount of water to obtain a slurry having a predetermined volume or a slurry containing microbubbles having a predetermined volume, which is pumped and sprayed onto an object to be coated with a spray gun. use.

Here, when the composition according to claim 3 of the present invention is used, in order to obtain a desired foaming ratio, the kind of the foaming agent is changed or the concentration is changed. In addition, in order to obtain fine air bubbles, in the case of stirring, the peripheral speed at the time of stirring is increased, and in the case of the column method (a method in which a foaming agent solution or a slurry containing a foaming agent and air are bubbled through the column). Can be used with a small column gap.

[0025]

The pollution-free, fire-resistant coating composition of the present invention is made of a lightweight inorganic aggregate by keeping the strength of the fire-resistant coating material and reducing shrinkage cracks during heating by keeping the proportion of hydraulic cement within a certain range. Among them, by increasing the number of closed-cell inorganic lightweight aggregates with a small particle size to obtain high heat insulation and good pumpability, the endothermic peak and endothermic amount of the endothermic substance should be specified before By selecting the diameter, the temperature range in which the endothermic reaction occurs with respect to the fireproof coating performance is made efficient, the effect per unit mass is made effective, the pollution-free fiber makes it safe and resistant to cracking, low viscosity increase and thickening The agent prevents the materials from separating and improves the pumpability and adhesion to the body, and the soft coagulant enhances the thick coating workability, and the foaming agent makes it a more economical fireproof coating material that is lightweight and has excellent heat insulation properties. To have.

[0026]

EXAMPLES The present invention will be described below with reference to examples. Example 1 The formulations of Example 12 and Comparative Examples 1 to 6 are shown in Tables 1 and 2 below, and their performances are shown in Table 3. In the table, the numerical value indicating the ratio is% by weight. Ingredient A ₁ is Portland cement, A ₂ is fly ash cement, B ₁ is inorganic lightweight aggregate Shirasu balloon (bulk specific gravity is 0.2) with particle size of 10-250μ, B ₂ is obsidian pearlite (Bulk specific gravity is 0.1) and particle size is 0.1-
1.2 mm, B ₃ is pearlite pearlite (0.2 in bulk specific gravity) and has a grain size of 30-600 μ, B ₄ is calcined hirucite (0.08 in bulk specific gravity) and 0 is grain size. .2-1.5 mm
, B ₅ is calcined hirucite (0.07 in bulk specific gravity) having a particle size of 2.1 mm to 3.3 mm, and C ₁ is an endothermic aluminum hydroxide having an average particle size of 1 μm. Thing, C ₂
Is an aluminum hydroxide having an average particle size of 100 μ, D ₁ is a chopped strand-processed carbon fiber having a fiber length of 10 mm, D ₂ is a chopped strand-processed vinylon fiber having a fiber length of 12 mm, and E ₁ is a low additive. Viscosity thickener hydroxyethyl cellulose HEC-UNICEL QP-09L (viscosity of 2% aqueous solution is 10 cps, manufactured by Daicel Chemical Industries, Ltd.), and F ₁ is a general formula M ₂ O · nSi.
Special water glass represented by O ₂ (wherein M is Na and n is 1.6) is Mizukanex # 150 (manufactured by Mizusawa Chemical Industry Co., Ltd.), and G ₁ is HLB 10 as a foaming agent. Polyoxyethylene lauryl ether (95 mm immediately after measurement of foaming force under specified conditions, 75 mm after 5 minutes), G ₂
Is N coconut oil fatty acid acyl L sodium glutamate as a foaming agent (160 mm immediately after the measurement of foaming force under predetermined conditions, 140 mm after 5 minutes), G ₃ is lauryl carboxymethyl hydroxyethyl imidazo as a foaming agent Linium betaine (170 mm immediately after foaming force measurement under predetermined conditions, 145 mm after 5 minutes), G ₄ had HLB of 14
The surfactant polyoxyethylene nonyl phenyl ether (see 16
0 mm, 135 mm after 5 minutes), G ₅ represents sorbitan monolaurate (15 mm immediately after foaming force measurement under predetermined conditions, 10 mm after 5 minutes), a surfactant having an HLB of 8. H ₁ is bentonite as a filler, H ₂ is a rust preventive as an auxiliary additive, and I ₁ is a water-soluble resin HiMetroses 90SH1 as an additive for other comparative examples.
5000 (manufactured by Shin-Etsu Chemical Co., Ltd.) and I ₂ represent Movinyl Powder DM-200 (manufactured by Hoechst Synthetic Co., Ltd.), which is a synthetic resin admixture.

[0027]

[Table 1]

[0028]

[Table 2]

With respect to 100 parts by weight of the composition according to these formulations, an appropriate amount of water of about 80 parts by weight was added and stirred to obtain a slurry of the fireproof coating composition. Then, in order to be subjected to various tests, it was sprayed on a steel material, an iron plate, etc. with a thickness of 20 mm, cured at 20 ° C. in a constant temperature room of 60% for 3 months to make a constant weight, and then subjected to each test.

[0030]

[Test items and test method] Fire resistance test A JIS-A-1304 standard is a test body in which each foam slurry composition is sprayed with a thickness of 20 mm onto a steel material with a thermocouple attached to the center to be cured for a predetermined amount to a constant weight. It heats along a heating curve and it measures and evaluates the time until it becomes 350 degreeC.
In addition, the appearance after the test was evaluated as ◯ and the deterioration was large as x. Adhesion strength test Using a 7 cm square test piece that has been sprayed on an iron plate and subjected to prescribed curing, perform an adhesion strength test in the standard state specified in JIS-A-6909. Compressive strength test A compressive strength test is carried out for 28 days according to the physical test method for cement of JIS-R-5201 to obtain the compressive strength. Thick spray test A steel plate that has been made vertical under a constant condition of room temperature of 20 ° C. and humidity of 60% is sprayed with a material of each composition having the same viscosity, and the thickness is determined so as not to slip. Foaming ratio The volume when 100 parts by weight of the composition is made into a foam slurry with an appropriate amount of water is a, and the volume when completely degassed in vacuum is b, and the capacity is increased by foaming according to the following formula. Ratio c
(%) Is calculated.

[0031]

[Formula 2]

[0032]

According to the present invention, it is possible to improve a poor working environment due to the scattering of fibers, which is a drawback of blown rock wool. Further, by using a large amount of closed-cell, inorganic lightweight aggregate in the composition ratio, it is possible to enhance the workability as well as the heat insulating property and the lightweight property. With regard to the endothermic substance as well, it is possible to ensure effective fire resistance performance by using the specific substance referred to in the present invention. Further, the pollution-free fiber can reduce cracks while ensuring safety. Further, the low viscosity increasing thickener can improve the pumping workability and at the same time increase the adhesion to the steel material. In addition, the soft coagulant can increase the coating thickness per time to improve workability. Further, the micro-bubbles are easily generated and stabilized, so that the coating layer is lightened and the refractory coating layer can be economically obtained. In addition, when white Portland cement is used as the hydraulic cement, cosmetics can be obtained by adding a coloring pigment.

[Brief description of drawings]

FIG. 1 is a diagram for explaining decomposition efficiency of an endothermic substance by a temperature gradient in a refractory coating layer at the maximum temperature in a furnace in a 1-hour fire resistance test.

FIG. 2 is a diagram illustrating the decomposition efficiency of an endothermic substance by the temperature gradient in the refractory coating layer at the maximum temperature in the furnace in the 2-hour fire resistance test.

FIG. 3 is a diagram illustrating the decomposition efficiency of an endothermic substance by the temperature gradient in the refractory coating layer at the maximum temperature in the furnace in the 3-hour fire resistance test.

[Explanation of symbols]

 α: Pyrolysis efficiency x: Fireproof coating layer thickness y: Thickness from the steel surface where the temperature reaches 500 ° C

[Table 3]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C04B 16:06 A 2102-4G 16:02) A 2102-4G

Claims (3)

[Claims] 1. When the total composition is 100% by weight,
10-40% by weight of hydraulic cement as a binder, 5 independent closed-cell inorganic lightweight aggregates selected from shirasu balloon, glass balloon, obsidian pearlite, etc.
6% of inorganic lightweight aggregates with a particle size of 2 mm or less consisting of 50% by weight or less of open-celled inorganic lightweight aggregates selected from burned hirucite, pearlite pearlite, etc.
40 wt%, the endothermic peak of the differential thermal curve in differential thermal analysis is 50 ℃ ~
It is in the range of 500 ° C and the endothermic amount in thermal decomposition is 300.
25 to 75% by weight of the specified endothermic substance having a cal / g or more and an average particle size of 10 μ or less, one or more selected from chopped strand processed carbon fiber, vinylon fiber, aramid fiber, nylon fiber, etc. 0.1 to 3% by weight of non-polluting fiber having a fiber length of 2 to 20 mm, and the viscosity of a 2% aqueous solution (20 ° C) is 3 of that of a BM type viscometer.
The viscosity value at 0 rpm is 1,000 cps or less. Synthetic polymer thickeners such as methyl cellulose, polyvinyl alcohol, hydroxyethyl cellulose or guar gum,
Any one of natural polymer thickeners such as alginic acid derivatives or a low viscosity thickener combining them is used in an amount of 1-10.
A pollution-free, fire-resistant coating composition, characterized in that a weight ratio of 1 to 3 is added. 2. When the composition according to claim 1 is 100 parts by weight, M ₂ O.nSiO ₂ (wherein M is an alkali metal and n is a number of 1.5 to 7.0) is shown. A pollution-free, fire-resistant coating composition comprising 0.1 to 10% by weight of a soft coagulant containing either a silicate compound or colloidal silica or a combination thereof. 3. When the composition according to claim 1 is used as 100 parts by weight, the foaming power is further measured at 25 ° C. by the loss-miles method under the condition of using a 0.1% aqueous foaming agent solution. (Hereinafter simply referred to as measurement of foaming force under predetermined conditions), the value immediately after 20 mm or more and after 5 minutes, the value 7 immediately after
A pollution-free, fire-resistant coating composition, characterized by comprising 0.01 to 3% by weight of a foaming agent of 5% or more in the composition according to claim 1 or 2.