JPH1087778A - Two-pack curable composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition containing a specific polyamine as curing component, causing no impairment of its surface appearance or no blistering due to foaming even at high temperatures and humidities, and capable of exhibiting its excellent low-temperature curability, thus useful in the construction material field. SOLUTION: This composition comprises (A) the main component comprising an isocyanate group-terminated polyurethane prepolymer formed by reaction between a polyol consisting mainly of a polyoxyalkylene polyol and a polyisocyanate and (B) a curing agent component comprising a polyamine alone consisting mainly of (B1 ) 2-chloro-1,4-phenylenediamine as active hydrogen compound. It is preferable that the component B1 accounts for 60-100 equivalent % of the polyamine and 50-68wt.% based on the component B of a filler such as calcium carbonate. Thus, this composition is improved in the balance between curability and coating film performance after cured and also improved in mechanical strength retention at 60-80 deg.C after cured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-pack type curable composition which cures at room temperature and is excellent in curability, appearance of the cured film, mechanical strength and heat resistance.

[0002]

2. Description of the Related Art Due to its excellent flexibility, polyurethane elastomers are used for a wide range of building materials such as waterproofing materials, flooring materials, sealing materials, and elastic pavement materials.

[0003] This polyurethane elastomer is usually
It is a two-pack type composition that cures at room temperature and comprises a main component mainly composed of an isocyanate group-terminated polyurethane prepolymer and a curing agent composed of an active hydrogen compound. For use as a waterproofing material, the main component is an isocyanate group-terminated polyurethane prepolymer obtained by the reaction of polyoxypropylene polyol with tolylene diisocyanate, and the main components are polyol and 4,4'-methylenebis (2-chloroaniline). The two-component type comprising a curing agent component is still mainstream at present.

[0004]

SUMMARY OF THE INVENTION 4,4'-Methylenebis (2-chloroaniline) used in conventional curing agents
Is a solid at ordinary temperature and is usually used by dissolving it in a polyol at a concentration of 30 to 50% by weight. However, the reactivity between the polyol and 4,4′-methylenebis (2-chloroaniline) is large with the polyol and the isocyanate group. Since they are different, a catalyst such as organometallic lead is indispensable to complete the reaction at room temperature.

However, the curability is greatly affected by the moisture concentration in the atmosphere and the environmental temperature, and the curability at 5 ° C. or less in winter is still insufficient even when the amount of the catalyst is increased, making it impossible to walk on the next day. Yes, it is not possible to repaint. In summer, the balance between pot life and curability is difficult to control only by the amount of the catalyst, the polyol hardly reacts without the catalyst, and the reaction of 4,4'-methylenebis (2-chloroaniline) with little catalyst is added. Is promoted and a sufficient pot life cannot be obtained. Furthermore, particularly in a high-temperature and high-humidity state, a reaction with moisture in the air occurs in parallel, and foams to impair the surface appearance and cause swelling.

[0006]

The present invention is the following invention which has solved the above-mentioned problems. A two-pack consisting of a main component containing an isocyanate group-terminated polyurethane prepolymer obtained by reacting a polyol containing a polyoxyalkylene polyol as a main component with a polyisocyanate, and a curing agent component containing substantially only a polyamine as an active hydrogen compound Curable composition, wherein the polyamine is 2-chloro-
A two-part curable composition comprising 1,4-phenylenediamine as a main component.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The polyoxyalkylene polyol in the present invention is usually produced by reacting a polyfunctional initiator with an alkylene oxide. The initiator referred to here is an active hydrogen compound having an average number of functional groups of 2 or more, specifically, ethylene glycol, dipropylene glycol,
Examples include polyhydric alcohols such as butanediol, glycerin, trimethylolpropane, and pentaerythritol; polyhydric phenols such as bisphenol A; polyhydric amines; and compounds obtained by adding a small amount of alkylene oxide to these.

Examples of the alkylene oxide include ethylene oxide, propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide and styrene oxide. Particularly, propylene oxide alone or a combination of propylene oxide and ethylene oxide is preferable.

A particularly preferred polyoxyalkylene polyol is obtained by mainly using propylene oxide, wherein oxypropylene groups are 80% by weight of all oxyalkylene groups.
It is a polyoxypropylene-based polyol occupying the above.

The average number of hydroxyl groups of the polyol is 2 to 4, especially 3 or less, particularly 2 to 2.5, and more preferably 2.1 to 2.2.
4, is preferred. If the average number of hydroxyl groups is less than 2, it becomes difficult to increase the molecular weight of the cured coating film, so that the cured product has insufficient mechanical strength. If it exceeds 4, the crosslink density becomes too high, and the elongation performance of the cured product deteriorates.

The polyoxyalkylene polyol is composed of a mixture of polyoxyalkylene diol and polyoxyalkylene triol and has a weight ratio of 60 to 90/40.
It is preferably from 10 to 10.

[0012] If the molecular weight of the polyoxyalkylene polyol is too small, the elongation of the cured product will be extremely poor, making it unsuitable for use as a waterproof material. However, if the molecular weight of the polyol is too high, the viscosity of the obtained polyurethane prepolymer may increase, and the mechanical strength of the cured product may be insufficient. Therefore, the molecular weight per hydroxyl group of the polyol is 20.
0-7000, especially 500-4000, especially 500
~ 2000, more preferably 700 ~ 1500.

Examples of the polyisocyanate include polyisocyanates such as aromatic, aliphatic and modified polyisocyanates having an average of two or more isocyanate groups. The viscosity, curability and cured coating film of the obtained prepolymer are considered. From the viewpoint of mechanical strength, it is preferable to select from tolylene diisocyanate, xylylene diisocyanate, and 4,4′-methylenebis (phenyl isocyanate). As the tolylene diisocyanate, tolylene diisocyanate having a 2,4-isomer content of 95% by weight or more is preferable.

The isocyanate group-terminated polyurethane prepolymer is prepared by mixing a polyisocyanate and a polyol containing a polyoxyalkylene polyol as a main component in a nitrogen atmosphere.
It is preferable that the reaction is carried out at 80 to 100 ° C. for several hours.

The polyurethane prepolymer obtained preferably has an isocyanate group content of 1 to 8% by weight. If it exceeds 8% by weight, the curing will be too fast, the resulting coating film will be hard, and sufficient elongation performance will not be exhibited. If the amount is less than 1% by weight, the mechanical strength of the coating film becomes weak, and it becomes difficult to exhibit the performance required as a waterproof material. 2.0-4.0% by weight,
In particular, 2.5 to 3.5% by weight is particularly preferred. further,
By changing the isocyanate group content within the above range, curability can be freely adjusted, and the same curing agent can cope with changes in environmental conditions in summer and winter.

At this time, the reaction is preferably carried out under the condition that the equivalent ratio of NCO group / OH group is more than 1.5 and less than 2.1. The content of the unreacted polyisocyanate in the obtained isocyanate group-terminated polyurethane prepolymer is preferably 2% by weight or less.

If the content of the unreacted polyisocyanate is more than 2% by weight, the reaction between the unreacted polyisocyanate and the diamine during the reaction between 2-chloro-1,4-phenylenediamine in the curing agent component and the polyurethane prepolymer. Precedes, and the reaction with the isocyanate groups in the polyurethane prepolymer is delayed, so that a large amount of polyurea hard segments are generated. This greatly affects the mechanical properties of the obtained coating film, and significantly impairs the elongation performance and mechanical strength required for the waterproof material.

In order to reduce the unreacted polyisocyanate content to 2% by weight or less, the reaction is carried out under the condition that the equivalent ratio of NCO group / OH group of the organic polyisocyanate and the polyoxyalkylene polyol is more than 1.5 and less than 2.1. Preferably. If it is not less than 1, the unreacted polyisocyanate content tends to exceed 2% by weight, which is not preferred. Also,
If it is less than 1.5, the resulting isocyanate group-terminated polyurethane prepolymer will have a high molecular weight, and the viscosity will be too high. More preferably, NCO group / O
The reaction is performed under the condition that the equivalent ratio of the H group is 1.8 to 1.95.

Further, first, a polyisocyanate is charged into the reactor, and then the polyol is gradually added while gradually adding a polyol.
Reaction at １００100 ° C. is conceivable. Further, an organic acid catalyst such as tin octoate, tin naphthenate, dibutyltin dilaurate, and zinc octoate may be added to promote the reaction.

The active hydrogen compound in the curing agent component consists essentially of only a polyamine, and the main component of the polyamine is 2-chloro-1,4-phenylenediamine. When the polyol is contained in the curing agent component, since a component having low reactivity is contained, the balance of the reactivity with the main component is deteriorated, and the curability tends to be significantly slowed down.
In particular, the curability at low temperatures is significantly deteriorated. Therefore, it is preferable that the curing agent component contains substantially no polyols.

Also, 2-chloro-1,4 in polyamine
-The proportion of phenylenediamine is preferably from 60 to 100 equivalent%. A coating film cured with only 2-chloro-1,4-phenylenediamine alone as an active hydrogen compound in the curing agent component has a stronger rigidity derived from the amine compound than a cured coating film using a curing agent component in combination with a polyol or the like. Since the density of urea bonds in the hard segment is high and the degree of reaction completion is high, the retention of mechanical strength at 60 to 80 ° C. for a long time can be greatly improved. This is also suitable for use in a heat insulating method in which solar heat is accumulated when a polyurethane coating is laminated on a rigid polyurethane heat insulating foam or the like.

The curing agent component preferably contains a filler. Calcium carbonate, talc, clay,
Silica, carbon and the like. Particularly, calcium carbonate is preferred. The content of the filler is 50 to 50% in the curing agent component.
Preferably it is 68% by weight. By setting the amount of the filler in the curing agent component to 50 to 68% by weight, the curability and the performance of the coated film after curing are maximized in a well-balanced manner. By adjusting the addition amount within the range, the time until the coating film can be walked can be greatly adjusted, and the hardness and mechanical strength of the coating film can be changed greatly.

By increasing the amount of the filler, the curability is increased, and the hardness and mechanical strength can be increased. However, if the content exceeds 68% by weight, the liquid component in the curing agent is small, so that kneading becomes difficult, and it becomes difficult to use it as a two-pack type waterproof material. If it is less than 50% by weight, the curability is insufficient and the strength of the coating film cannot be satisfied.

It is preferable to use a plasticizer for the curing agent component. Examples of the plasticizer include dioctyl phthalate, dibutyl phthalate, dinonyl phthalate, diisononyl phthalate, dioctyl adipate, chlorinated paraffin, and a petroleum plasticizer. The content is preferably 0 to 60% by weight, particularly preferably 10 to 50% by weight in the curing agent component.

[0025] The curing agent component may further contain additives selected from pigments, solvents, catalysts, and stabilizers.
Examples of the pigment include inorganic pigments such as chromium oxide and titanium oxide, and organic pigments such as phthalocyanine pigment. Solvents include aromatic hydrocarbons such as toluene and xylene and n
-Aliphatic hydrocarbons such as heptane and n-decane.

As a catalyst, a catalyst known in polyurethane chemistry may be added in order to accelerate curing after coating. For example, tin octanoate, tin naphthenate, dibutyltin dilaurate, higher fatty acid metal salts such as zinc octanoate and tin, cobalt, nickel,
Metal salts composed of iron, zinc, lead and the like, triethylamine, dimethylcyclohexylamine, 1,4-diazabicyclo [2.2.2] octane, 1,5-diazabicyclo [4.3.0] non-5-ene, Tertiary amines such as 1,8-diazabicyclo [5.4.0] undec-7-ene and diethylbenzylamine are exemplified. Further, since the curing agent component is a diamine alone, an organic acid such as octanoic acid, naphthenic acid and acetic acid may be used.

Further, stabilizers such as an antioxidant, an ultraviolet absorber and a dehydrating agent generally used in polyurethane resins can be blended.

The amount of the additive is not particularly limited, but is generally preferably from 40 to 80% by weight in the curing agent component.

The equivalent ratio (NCO / NH ₂ ) between the isocyanate group of the main component and the amino group of the curing agent component is 0.9 to 0.9.
It is preferably 1.8.

The two-part curable composition of the present invention has excellent curability especially in winter. Therefore, the temperature at which the two-part curable composition is cured is preferably 20 ° C. or less,
0 ° C. or lower is particularly preferred. Most preferably, it is 5 ° C. or lower.

As described above, the two-part curable composition of the present invention is hardly affected by the moisture in the hardener and the moisture concentration in the atmosphere, and foams even in a high-temperature and high-humidity state to improve the surface appearance. No damage or swelling. In particular, the curability at 5 ° C. or less in winter is remarkably improved, and it is possible to walk on the next day, so that sufficient recoating can be performed. The two-part curable composition of the present invention can also be used as a waterproof material, a floor material (coated floor material) and the like.

[0032]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples (Examples 1 to 10) and Comparative Examples (Examples 11 to 12), but the present invention is not limited thereto.

A polyurethane isocyanate-terminated prepolymer was synthesized using the following polyoxyalkylene polyol. Polyol A: Polyoxypropylene diol having a molecular weight of 2,000, Polyol B: Polyoxypropylene diol having a molecular weight of 3,000, Polyol C: Polyoxypropylene triol having a molecular weight of 3,000, Polyol D: Polyoxypropylene having a molecular weight of 4,000 Triol.

(Example 1) "Synthesis of the main component" In 800 g of polyol A and 200 g of polyol D, 165 g of tolylene diisocyanate containing 80% by weight of 2,4-isomer (equivalent ratio of NCO group / OH group = 2.0) was added and the mixture was reacted at 80 ° C. for 6 hours in a reaction vessel to obtain a polyurethane prepolymer having an isocyanate group content of 3.40% by weight and a viscosity of 6,500 cP / 20 ° C.

"Preparation of curing agent component" 52.6 g of 2-chloro-1,4-phenylenediamine and 252.4 g of dioctyl phthalate previously heated and melted were charged into a kneader, and 600 g of calcium carbonate and 5 g of titanium oxide were further added.
0 g, xylene 30 g, carbon black 10 g, and lead octanoate (lead content 24% by weight) 5 g were charged and uniformly mixed.

The above main component and curing agent component were mixed at a 1/1 weight ratio (NCO / NH ₂ equivalent ratio = 1.1) and used as a waterproof material.

(Example 2) "Synthesis of main component" 800 g of polyol B and 200 g of polyol C had a 2,4-isomer content of 100% by weight.
127.6 g of tolylene diisocyanate (NCO group /
(Equivalent ratio of OH group = 2.0) was added, and 80
The reaction was carried out at 6 ° C for 6 hours, and the isocyanate group content was 2.7.
A polyurethane prepolymer having 0% by weight and a viscosity of 7,000 cP / 20 ° C. was obtained.

"Preparation of curing agent component" 41.8 g of 2-chloro-1,4-phenylenediamine and 263.2 g of dioctyl phthalate previously heated and melted were charged into a kneader, and further, 600 g of calcium carbonate and 5 g of titanium oxide were added.
0 g, xylene 30 g, carbon black 10 g, and lead octanoate (lead content 24% by weight) 5 g were charged and uniformly mixed.

The above main component and curing agent component were mixed at a 1/1 weight ratio (NCO / NH ₂ equivalent ratio = 1.1) and used as a waterproof material.

(Example 3) "Synthesis of main component" 800 g of polyol A and 200 g of polyol C were added to 188.
0 g (equivalent ratio of NCO group / OH group = 2.0) was added, and the reaction was carried out at 80 ° C. for 9 hours in a reaction vessel. The content of free isocyanate group was 3.50% by weight, and the viscosity was 7,500 cP / 2.
A polyurethane prepolymer at 0 ° C. was obtained.

"Preparation of curing agent component" 54.1 g of 2-chloro-1,4-phenylenediamine and 240.9 g of dioctyl phthalate previously heated and melted were charged into a kneader, and 600 g of calcium carbonate and 5 g of titanium oxide were further added.
0 g, xylene 30 g, carbon black 10 g, and lead octanoate (lead content 24% by weight) 15 g were charged and uniformly mixed.

The above main component and curing agent component were mixed at a 1/1 weight ratio (NCO / NH ₂ equivalent ratio = 1.1) and used as a waterproof material.

(Example 4) "Synthesis of the main component" 162.0 g of 4,4'-methylenebis (phenylisocyanate) was added to 800 g of polyol B and 200 g of polyol D (equivalent ratio of NCO group / OH group = 1.9). And reacted at 80 ° C. for 4 hours in a reaction vessel, and dissolved by adding 129 g (10% by weight) of xylene, having an isocyanate group content of 1.95% by weight and a viscosity of 6,9.
A polyurethane prepolymer of 500 cP / 20 ° C. was obtained.

"Preparation of curing agent component" 30.1 g of 2-chloro-1,4-phenylenediamine previously melted by heating and 279.9 g of dioctyl phthalate were put into a kneader, and further 600 g of calcium carbonate and titanium oxide 5 g were added.
0 g, xylene 30 g and carbon black 10 g were charged and mixed uniformly.

The main component and the hardener were mixed at a 1/1 weight ratio (NCO / NH ₂ equivalent ratio = 1.1) and used as a waterproof material.

(Example 5) "Synthesis of main component" 800 g of polyol A and 200 g of polyol C were added to 157 g of tolylene diisocyanate having a 2,4-isomer content of 80% by weight (equivalent ratio of NCO group / OH group = 1.8) was added, and the mixture was reacted at 80 ° C. for 9 hours in a reaction vessel. The content of free polyisocyanate monomer was 0.52% by weight, the content of isocyanate group was 2.90% by weight, and the viscosity was 10,500 cP / 20 ° C. Was obtained.

"Preparation of curing agent component" 44.9 g of 2-chloro-1,4-phenylenediamine previously melted by heating and 260.1 g of dioctyl phthalate were put into a kneader, and further 600 g of calcium carbonate and 5 g of titanium oxide were added.
0 g, xylene 30 g, carbon black 10 g, and lead octanoate (lead content 24% by weight) 5 g were charged and uniformly mixed.

The above main component and curing agent component were mixed at a 1/1 weight ratio (NCO / NH ₂ equivalent ratio = 1.1) and used as a waterproof material.

(Example 6) "Synthesis of main component" 800 g of polyol A and 200 g of polyol C had a 2,4-isomer content of 100% by weight.
174 g of tolylene diisocyanate (NCO group / OH
(Equivalent ratio of group = 2.0) was added at 80 ° C. in a reaction vessel.
The reaction was carried out for a time to obtain a polyurethane prepolymer having an isocyanate group content of 3.50% by weight and a viscosity of 7,500 cP / 20 ° C.

"Preparation of curing agent component" 27.1 g of 2-chloro-1,4-phenylenediamine and 277.9 g of dioctyl phthalate previously heated and melted were charged into a kneader, and further, 600 g of calcium carbonate and 5 g of titanium oxide were added.
0 g, xylene 30 g, carbon black 10 g, and lead octanoate (lead content 24% by weight) 5 g were charged and uniformly mixed.

The main component and the hardener were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.1) and used as a waterproof material.

(Example 7) "Synthesis of main component" In 700 g of polyol A and 300 g of polyol C, the 2,4-isomer content was 100% by weight.
161 g of NCO / OH
The equivalent ratio of the groups = 1.85) was added, and the mixture was heated at 80 ° C. in a reaction vessel.
The reaction was carried out for 9 hours and the free isocyanate group content was 3.0.
A polyurethane prepolymer having a weight percentage of 9,500 cP / 20 ° C. was obtained.

"Preparation of curing agent component" 23.3 g of 2-chloro-1,4-phenylenediamine previously melted by heating and 281.7 g of dioctyl phthalate were charged into a kneader, and 600 g of calcium carbonate and 5 g of titanium oxide were added.
0 g, xylene 30 g, carbon black 10 g, and lead octanoate (lead content 24% by weight) 5 g were charged and uniformly mixed.

The main component and the curing agent component were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.1) and used as a waterproof material.

(Example 8) "Synthesis of main component" 600 g of polyol B and 400 g of polyol D had a 2,4-isomer content of 100% by weight.
121.8 g of tolylene diisocyanate (NCO group /
(Equivalent ratio of OH group = 2.0) was added, and 80
The reaction was carried out at 9 ° C for 9 hours, and the isocyanate group content was 2.6.
A polyurethane prepolymer having 0% by weight and a viscosity of 9,000 cP / 20 ° C. was obtained.

"Preparation of curing agent component" 20.1 g of 2-chloro-1,4-phenylenediamine and 284.9 g of dioctyl phthalate, which were previously heated and melted, were put into a kneader, and 600 g of calcium carbonate and 5 g of titanium oxide were further added.
0 g, xylene 30 g, carbon black 10 g, and lead octanoate (lead content 24% by weight) 5 g were charged and uniformly mixed.

The main component and the curing agent component were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.1) and used as a waterproof material.

(Example 9) "Synthesis of main component" 800 g of polyol A and 200 g of polyol C had a 2,4-isomer content of 100% by weight.
174 g of tolylene diisocyanate (NCO group / OH
(Equivalent ratio of group = 2.0) was added at 80 ° C. in a reaction vessel.
The reaction was carried out for a time to obtain a polyurethane prepolymer having an isocyanate group content of 3.50% by weight and a viscosity of 7,500 cP / 20 ° C.

"Preparation of curing agent component" 27.1 g of 2-chloro-1,4-phenylenediamine previously melted by heating and 327.9 g of dioctyl phthalate were put into a kneader, and further 550 g of calcium carbonate and titanium oxide 5
0 g, xylene 30 g, carbon black 10 g, and lead octanoate (lead content 24% by weight) 5 g were charged and uniformly mixed.

The main component and the curing agent component were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.1) and used as a waterproof material.

Example 10 Synthesis of Main Component The same prepolymer as in Example 9 was used as the main component.

"Preparation of curing agent component" 27.1 g of 2-chloro-1,4-phenylenediamine and 227.9 g of dioctyl phthalate previously heated and melted were charged into a kneader, and 650 g of calcium carbonate and titanium oxide 5 were added.
0 g, xylene 30 g, carbon black 10 g, and lead octanoate (lead content 24% by weight) 5 g were charged and uniformly mixed.

The main component and the curing agent component were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.1) and used as a waterproof material.

(Example 11) "Synthesis of main component" The same prepolymer as in Example 1 was used as the main component.

"Preparation of curing agent component" 74.9 g of 4,4'-methylenebis (2-chloroaniline) previously melted by heating and 174.7 g of polyol A were charged into a kneader, and 600 g of calcium carbonate and titanium oxide were further added. 5
0 g, dioctyl phthalate 60.4 g, xylene 30
g, 10 g of carbon black and 10 g of lead octanoate (lead content: 24% by weight) were uniformly mixed.

The main component and the hardener component were mixed at a 1/1 weight ratio (NCO / (NH ₂ + OH) equivalent ratio = 1.1) and used as a waterproof material.

(Example 12) "Synthesis of main component" The same prepolymer as in Example 1 was used as the main component.

"Preparation of curing agent component" Into a kneader were charged 48.3 g of 2-chloro-1,4-phenylenediamine, which had been heated and melted in advance, 191.6 g of dioctyl phthalate, and 60.1 g of polyol A. 600 g, titanium oxide 50 g, xylene 30 g,
10 g of carbon black and 10 g of lead octanoate (lead content: 24% by weight) were charged and uniformly mixed.

The main component and the curing agent component were mixed at a 1/1 weight ratio (NCO / (NH ₂ + OH) equivalent ratio = 1.1) and used as a waterproof material.

[Evaluation] The waterproofing agents obtained in Examples 1 to 12 were evaluated as follows. Table 1 shows the results.

[Usable time] The possible time during which the coating operation can be performed after the main component and the curing agent are mixed. Measured at 5 ° C, 20 ° C and 35 ° C. "-" In the table was not measured. After a "curable" coating, the time required for a person to walk on it. Measured at 5 ° C, 20 ° C and 35 ° C.
"-" In the table was not measured. "Basic physical properties" Mechanical properties of a coating film measured according to JIS A6021. In the table, E is the elongation at break (unit:%),
T _s is the tensile strength (unit: kg / cm ² ), and _Tr is the tear strength (unit: kg / cm). "Heat resistance" Mechanical properties after immersion in hot water at 60 ° C for 7 days.

[0072]

[Table 1]

[0073]

As described above, the two-part curable composition of the present invention is hardly affected by the moisture in the curing agent or the moisture concentration in the atmosphere, and foams even in a high-temperature and high-humidity state. Does not impair appearance or swell. Also, especially at 5 ° C in winter
The curability of the following is remarkably improved, and it is possible to walk on the next day, so that sufficient recoating can be performed.

Claims (2)

[Claims] 1. A main component containing an isocyanate group-terminated polyurethane prepolymer obtained by reacting a polyol containing a polyoxyalkylene polyol as a main component with a polyisocyanate, and a curing agent containing substantially only a polyamine as an active hydrogen compound. A two-part curable composition comprising a component, wherein the polyamine is mainly composed of 2-chloro-1,4-phenylenediamine. 2. The composition according to claim 1, which is used for waterproofing materials and flooring materials.