JPH1095826A - Two-component curable composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a two-component curable compsn. which is excellent in mechanical strengths and heat resistance and gives a cured coating film excellent in external appearance by using a specific arom. polyamine mixture as the curative component. SOLUTION: This two-component curable compsn. is a combination of a maior component contg. an isocyanate-terminated polyurethane prepolymer obtd. by reacting a polyol mainly comprising a polyoxyalkylene polyol with a polyisocyanate with a curative component substantially contg. a polyamine mixture alone as the active hydrogen compds. The polyamine mixture comprises a 4,4'-methylenedianiline compd. with only one of the o-positions of the two amino groups alkylated, a 4,4'-methylenedianiline compd. with both o-positions of the two amino groups alkylated, and diethyltoluenediamine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-part curable composition having excellent curability, appearance of a 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. Further, particularly in a high-temperature and high-humidity state, a reaction with moisture in the air occurs in parallel, which causes foaming to impair the surface appearance and causes swelling.

[0006]

The present invention is the following invention which has solved the above-mentioned problems. 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. In the liquid type curable composition, the polyamine is (a) 4,4′-methylene-dianiline in which only one ortho position to each amino group is substituted with an alkyl group, and (b) both ortho groups to each amino group. A two-part curable composition, which is a mixture of 3,4'-methylene-dianiline substituted at an alkyl group and (c) three kinds of aromatic polyamines of diethyltoluenediamine.

[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.

As the alkylene oxide, ethylene oxide, propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, styrene oxide and the like are preferred, and propylene oxide alone or a combination of propylene oxide and ethylene oxide is particularly preferred.

Particularly preferred polyoxyalkylene polyols are polyoxypropylene-based polyols in which oxypropylene groups obtained mainly using propylene oxide account for at least 80% by weight of all oxyalkylene groups.

The average number of hydroxyl groups of the polyol is preferably 2 to 4. It is preferably 3 or less, particularly preferably 2 to 2.5, and more preferably 2.1 to 2.4. 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.
It is preferably from 0 to 7000. Preferably 500
4,000, 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). In particular, tolylene diisocyanate having a 2,4-isomer content of 95% by weight or more is particularly preferred.

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 to 4.0% by weight is preferred, and 2.5 to 3.5% by weight is particularly preferred.

The content of unreacted polyisocyanate in the obtained isocyanate group-terminated polyurethane prepolymer is preferably 2% by weight or less.

When the content of the unreacted polyisocyanate is more than 2% by weight, the reaction between the unreacted polyisocyanate and the amine compound occurs in the course of the reaction between the aromatic polyamine mixture in the curing agent component and the polyurethane polymer,
The reaction with the isocyanate groups in the polyurethane prepolymer is delayed, and 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 content of unreacted polyisocyanate to 2% by weight or less, the reaction is carried out under the condition that the equivalent ratio of NCO group / OH group of organic polyisocyanate and 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 a reactor, and then 80 to 80 while gradually adding a polyol.
The reaction is preferably performed at 100 ° C. 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 is substantially only a polyamine, and the polyamine is (a) 4,4'-methylene-form having only one ortho-position to each amino group substituted with an alkyl group. A mixture of three kinds of aromatic polyamines, dianiline, and (b) 4,4′-methylene-dianiline in which both ortho positions to each amino group are substituted with an alkyl group, and (c) diethyltoluenediamine.

(A) 4,4'-methylene-dianiline in which one of the ortho positions to each amino group is substituted with an alkyl group, formula (1), (b) Both ortho positions to each amino group are substituted with an alkyl group 4,4′-methylene-dianiline is represented by Formula 2.

[0022]

Embedded image

R ^{1 to} R ⁶ are each an alkyl group, preferably an alkyl group having 6 or less carbon atoms, and may be the same or different. Specific examples of the alkyl group having 6 or less carbon atoms in R ^{1 to} R ⁶ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a tert-butyl group.

The alkyl group, which is a substituent, tends to have a lower polyamine reactivity as the number of carbon atoms increases. Also,
In (a) and (b), the reactivity is lower when the number of substituents is larger (b). Therefore, the reactivity of the curing agent component can be arbitrarily adjusted by adjusting the number of carbon atoms of the alkyl group as a substituent of (a) and (b) and the mixing ratio of (a) and (b).
The preferred mixing ratio of (a) and (b) is (a) /
(B) = 10-90 / 90-10.

(A) and (b) are preferably diamines obtained by subjecting formaldehyde to a condensation reaction with an alkyl-substituted aniline having one or two ortho-positions to the amino group of the aniline substituted with an alkyl group.

Specific examples of (a) include 4,4'-methylenebis (2-ethylaniline) and 4,4'-methylenebis (2-butylaniline). Specific examples of (b) include 4,4′-methylenebis (2,6-dimethylaniline) and 4,4′-methylenebis (2,6-diethylaniline). (A), (b)
May be a mixture of two or more compounds.

(C) 3,5-diethyltoluenediamine
It is preferably a mixture of diethyltoluene-2,4-diamine and 3,5-diethyltoluene-2,6-diamine, particularly preferably 70 to 85% by weight of the former.

In the present invention, the pot life and curability can be arbitrarily adjusted by mixing three or more aromatic polyamines having different reactivities in different ratios. In one kind of aromatic polyamine, the pot life and the range of curability are limited by the reactivity inherent in the amine, and in two kinds of aromatic polyamines, a highly reactive aromatic polyamine reacts with an isocyanate group first, The aromatic polyamine having lower reactivity does not completely react, and it is difficult for the cured coating film to have sufficient mechanical strength. By using a mixture of three kinds of aromatic polyamines, curing proceeds in a stepwise manner, so that a sufficient pot life can be secured, crystallization does not easily occur even during curing, and the amine having the lowest reactivity easily completes the reaction.

The preferred mixing ratio of (a) + (b) and (c) is [(a) + (b)] / (c) = 10-95 by weight.
/ 90-5. The mixing ratio of each of (a), (b) and (c) is not particularly limited, but it is preferable that one amine contains at least 5 mol%, particularly preferably at least 8 mol%, of the total polyamine.

As described above, in the present invention, the curing agent component consists essentially of only a polyamine as an active hydrogen compound. When a low-reactivity component such as a polyol is mixed, the balance of the reactivity with the main component is deteriorated, and the curability tends to be significantly slowed down.

A coating film cured with an aromatic polyamine mixture as an active hydrogen compound in the curing agent component has a stronger hard segment urea derived from the amine compound than a cured coating film in which a polyol or the like is used in combination with the curing agent component. Since the bond density is high and the degree of reaction completion is high, the mechanical strength retention 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. Therefore, it is preferable that the curing agent component does not substantially contain a polyol as an active hydrogen compound.

[0032] 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 is hardened and can be walked can be largely adjusted, and the hardness and mechanical strength of the coating film can be greatly changed.

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 use becomes difficult. If it is less than 50% by weight, the curability is insufficient and the strength of the coating film cannot be satisfied.

The curing agent component preferably contains a plasticizer. As a plasticizer, dioctyl phthalate, dibutyl phthalate, dinonyl phthalate, diisononyl phthalate,
Dioctyl adipate, chlorinated paraffins, petroleum plasticizers and the like. The content is 0 in the curing agent component.
-60% by weight, particularly preferably 10-50% by weight.

The hardener 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.

Examples of the solvent include aromatic hydrocarbons such as toluene and xylene and aliphatic hydrocarbons such as n-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 substantially only a diamine, an organic acid such as octanoic acid, naphthenic acid, and acetic acid may be used.

Further, stabilizers such as antioxidants, ultraviolet absorbers and dehydrating agents 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 ) of the isocyanate group of the main component to 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. That is, the two-part curable composition can be cured at 20 ° C. or lower. Curing can be performed at a temperature of 10 ° C. or less, and even 5 ° C. or less.

As described above, the two-part curable composition of the present invention is hardly affected by the moisture in the curing agent component and the moisture concentration in the air, and foams even in a high-temperature and high-humidity state to form a surface. No damage or swelling. Also, especially in winter
The curability at ℃ or lower is remarkably improved, walking becomes possible on the next day, and sufficient recoating is possible. 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.

[0043]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples (Examples 1 to 6) and Comparative Examples (Examples 7 to 12), but the present invention is not limited thereto.

A polyurethane isocyanate-terminated prepolymer was synthesized using the following polyoxyalkylene polyol. The following compounds were used as the aromatic polyamine compounds. 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.

Polyamine a: 4,4'-methylenebis (2-ethylaniline) (manufactured by Nippon Kayaku Co., Ltd .: Kayahard A)
A), polyamine b: 4,4′-methylenebis (2,6-diethylaniline) (manufactured by Nippon Kayaku Co., Ltd .: Kayabond C-30)
0), polyamine c: diethyltoluenediamine: (manufactured by Ethyl Corporation, 3,5-diethyltoluene-2,4)
-A mixture of diamine and 3,5-diethyltoluene-2,6-diamine in a ratio of 74 to 80/18 to 24 (weight ratio)).

(Example 1) (Synthesis of main component) 800 g of polyol A and 200 g of polyol D had a 2,4-isomer content of 100% by weight.
165 g of tolylene diisocyanate (NCO group / OH
(Equivalent ratio of group = 2.0) was added, and the mixture was heated at 80 ° C.
The reaction was carried out for an hour 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) 7.8 g of polyamine b and 70.2 g of dioctyl phthalate, which were previously heated and melted, were put into a kneader, and 21.4 g of polyamine a and 10.5 g of polyamine c were added. 230.1 g of dioctyl phthalate, 600 g of calcium carbonate, 50 g of titanium oxide and 10 g of carbon black 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 = 1.2) and used as a waterproof material.

(Example 2) (Synthesis of main component) In 800 g of polyol B and 200 g of polyol C, the 2,4-isomer content was 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 a curing agent component) Into a kneader were charged 6.2 g of polyamine b, which had been heated and melted in advance, and 55.8 g of dioctyl phthalate, and 11.9 g of polyamine a and 11.9 g of polyamine c. 254.2 g of dioctyl phthalate, 600 g of calcium carbonate, 50 g of titanium oxide, and 10 g of carbon black 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 = 1.2) and used as a waterproof material.

(Example 3) (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.
174.0 g (NCO group /
(Equivalent ratio of OH group = 2.0) was added, and 80
The reaction was carried out at 6 ° C for 6 hours to obtain a polyurethane prepolymer having a free isocyanate group content of 3.50 wt% and a viscosity of 7,500 cP / 20 ° C.

(Preparation of a curing agent component) In a kneader, 16.1 g of polyamine b and 144.9 g of dioctyl phthalate previously heated and melted were charged, and 13.2 g of polyamine a and 12.4 g of polyamine c were further added. Dioctyl phthalate (153.4 g), calcium carbonate (600 g), titanium oxide (50 g) and carbon black (10 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 = 1.2) and used as a waterproof material.

(Example 4) (Synthesis of main component) 800 g of polyol B and 200 g of polyol D had a 2,4-isomer content of 100% by weight.
118.9 g (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 2.5.
A polyurethane prepolymer having 2% by weight and a viscosity of 8,500 cP / 20 ° C. was obtained.

(Preparation of curing agent component) 15.5 g of polyamine b and 139.5 g of dioctyl phthalate previously heated and melted were charged into a kneader. Further, 9.5 g of polyamine a and 6.7 g of polyamine c were added. 168.8 g of dioctyl phthalate, 600 g of calcium carbonate, 50 g of titanium oxide and 10 g of carbon black 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 = 1.2) and used as a waterproof material.

(Example 5) (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.
157 g of NCO group / OH
Equivalent ratio of groups = 1.8) was added, and the mixture was added at 80 ° C. and 6
The reaction was carried out for an hour to obtain a polyurethane prepolymer having an isocyanate group content of 2.90% by weight and a viscosity of 10,500 cP / 20 ° C.

(Preparation of a curing agent component) Into a kneader, 26.7 g of polyamine b and 240.3 g of dioctyl phthalate previously heated and melted were charged, and 5.5 g of polyamine a and 6.4 g of polyamine c were further added. 61.1 g of dioctyl phthalate, 600 g of calcium carbonate, 50 g of titanium oxide, and 10 g of carbon black 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 = 1.2) and used as a waterproof material.

(Example 6) (Synthesis of main component) In 800 g of polyol A and 200 g of polyol C, the content of 2,4-isomer was 100% by weight.
174 g of tolylene diisocyanate (NCO group / OH
(Equivalent ratio of group = 2.0) was added, and the mixture was heated at 80 ° C.
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) 40.3 g of polyamine b and 290.7 g of dioctyl phthalate, which had been heated and melted in advance, were put into a kneader, and 4.4 g of polyamine a and 4.6 g of polyamine c were further added. 600 g of calcium carbonate, 50 g of titanium oxide, and 10 g of carbon black were charged and uniformly mixed.

The main component and the curing agent were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.2) 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 content of 2,4-isomer was 100% by weight.
161 g of NCO group / 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 6 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) In a kneader, 26.5 g of polyamine c and dioctyl phthalate 313.5 were added.
g, calcium carbonate 600 g, titanium oxide 50
g, and 10 g of carbon black were charged and uniformly mixed.

The above main component and hardener were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.2) and used as a waterproof material.

(Example 8) (Synthesis of main component) In 600 g of polyol B and 400 g of polyol D, the content of 2,4-isomer was 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 6 ° C for 6 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 a curing agent component) In a kneader, 16.4 g of polyamine a, 11.5 g of polyamine c, 312.1 g of dioctyl phthalate, and calcium carbonate 60
0 g, titanium oxide 50 g, and carbon black 10
g was added and mixed uniformly.

The above main component and curing agent component were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.2) and used as a waterproof material.

(Example 9) (Synthesis of main component) In 800 g of polyol A and 200 g of polyol C, the 2,4-isomer content was 100% by weight.
174 g of tolylene diisocyanate (NCO group / OH
(Equivalent ratio of group = 2.0) was added, and the mixture was heated at 80 ° C.
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) 26.9 g of polyamine b and 242.1 g of dioctyl phthalate previously heated and melted were charged into a kneader, and 1 part of polyamine c was added.
5.4 g, 55.6 g of dioctyl phthalate, 600 g of calcium carbonate, 50 g of titanium oxide, and 10 g of carbon black were charged and uniformly mixed.

The main component and the curing agent were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.2) 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) In a kneader, 44.1 g of polyamine a, 295.9 g of dioctyl phthalate,
Further, 600 g of calcium carbonate, 50 g of titanium oxide, and 10 g of carbon black were charged and uniformly mixed.

The main component and the curing agent were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.2) 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) Into a kneader were charged 52.3 g of polyamine b which had been heated and melted in advance, and 287.7 g of dioctyl phthalate, and 600 g of calcium carbonate, 50 g of titanium oxide, and 10 g of carbon black. And evenly mixed.

The main component and the hardener were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.2) 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) 31.4 g of polyamine b and 291.5 g of dioctyl phthalate, which were previously heated and melted, were put into a kneader.
17.1 g, calcium carbonate 600 g, titanium oxide 5
0 g and 10 g of carbon black were charged and uniformly mixed.

The main component and the hardener were mixed at a 1/2 weight ratio (NCO / NH ₂ equivalent ratio = 1.2) and used as a waterproof material.

[Evaluation] The waterproofing materials obtained in Examples 1 to 12 were evaluated for the following items. Table 1 shows the results. "Usable time" The possible time during which the coating operation can be performed after mixing the main component and the curing agent. Measured at 5 ° C, 20 ° C and 35 ° C.

The time required after a "curable" coating is applied until a person can walk on it. Measured at 5 ° C, 20 ° C and 35 ° C. "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 ⁻¹ ).

[0084]

[Table 1]

[0085]

As described above, the two-pack type room temperature curable composition of the present invention is hardly affected by the moisture in the curing agent component and the moisture concentration in the atmosphere, and foams even in a high temperature and high humidity state. It does not impair the surface appearance or swell. 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. further,
Since the pot life can be sufficiently obtained, the workability is excellent.

Claims (2)

[Claims] 1. A curing agent containing only a polyamine as an active hydrogen compound and 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. A two-part curable composition comprising: a) a polyamine, wherein the polyamine comprises (a) one ortho-position to each amino group;
4,4′-methylene-in which only one is substituted with an alkyl group
A mixture of dianiline, and (b) 4,4′-methylene-dianiline in which both ortho positions to each amino group are substituted with an alkyl group, and (c) diethyltoluenediamine. Two-part curable composition. 2. The composition according to claim 1, wherein the two-part curable composition is a waterproof material or a floor material.