JPH1177940A - Waterproof structure and forming method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waterproof structure excellent in weatherability. SOLUTION: This waterproof structure has a waterproof layer, which is obtained by reacting a base component including a polyurethane prepolymer having terminal isocyanate groups and a hardener component including a diethyl toluene diamine with each other, and a protective layer, which is obtained by reacting a base component including a polyurethane prepolymer having terminal aromatic polyisocyanate-based isocyanate groups and a hardener component including a fluorinecontaining copolymer having hydroxyl groups with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproofing material which cures at room temperature, and more particularly to a curability, a waterproofing property after curing, a paint film appearance,
The present invention relates to a waterproof material having excellent durability.

[0002]

2. Description of the Related Art Conventionally, polyurethane waterproof layers have been used for a wide range of building materials such as rooftops, verandas, corridors and stairs of buildings, and elastic pavement of sports facilities. Such a coating waterproof layer usually includes a waterproof layer mainly for waterproofing, and a protective layer for protecting the waterproof layer in many cases. For the purpose of improving the weather resistance of the waterproof material, a waterproof structure having a fluorine-containing polyurethane-based protective layer composed of an aliphatic polyisocyanate, a fluorine-containing copolymer having a hydroxyl group, and a polyol has also been proposed (Japanese Patent Application Laid-open No. Sho.
2-73944).

Further, as a conventional waterproofing material, an isocyanate group-terminated polyurethane prepolymer is used as a main component,
Two-component curable compositions comprising a curing agent component containing a polyol and 4,4′-methylenebis (2-chloroaniline) (hereinafter, MOCA) as main components are mainly used.
MOCA used as a curing agent component is solid at room 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 MOCA differs greatly between the polyol and MOCA at room temperature. A catalyst such as organometallic lead is indispensable in order to complete the reaction.

However, the curability is greatly affected by the moisture concentration in the atmosphere and the environmental temperature.
Even if the amount of the catalyst is increased, the curability is still insufficient, so that it is impossible to walk on the next day and the recoating is impossible. In summer, the balance between pot life and curability is difficult to control only with the amount of catalyst, the polyol hardly reacts without catalyst, and the addition of even a small amount of catalyst accelerates the MOCA reaction, making it impossible to obtain sufficient pot life. . 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.

[0005] In addition to these problems, MOCA is difficult to handle, so that diethyltoluenediamine (hereinafter referred to as D) having high reactivity as a polyamine in place of MOCA is used.
A waterproof material using ETDA has been proposed (Japanese Unexamined Patent Publication No.
143818 etc.).

[0006]

DISCLOSURE OF THE INVENTION DETDA is MOCA
If DETDA is used as the curing agent component of the waterproofing material, it can be easily cured without using a catalyst, but phthalic acid must be used to secure the pot life suitable for hand coating. A large amount of a plasticizer such as dioctyl (hereinafter, DOP) must be used. However, when an attempt is made to form a conventional fluorine-containing polyurethane-based protective layer on a waterproof layer obtained by curing such a waterproof material, tack is left on the surface of the protective layer due to the influence of the plasticizer, and the waterproof layer and the protective layer are not bonded. Adhesion between them also tended to be significantly worse.

[0007]

The present invention is the following invention which has solved the above-mentioned problems. A main component (a1) containing an isocyanate group-terminated polyurethane prepolymer obtained by reacting a polyisocyanate and a polyol, and a curing agent component (a2) containing diethyltoluenediamine as an active hydrogen compound. A main component (b) containing a polyurethane-based waterproofing layer (A) and an isocyanate group-terminated polyurethane prepolymer obtained by reacting an aromatic polyisocyanate and / or an aromatic polyisocyanate with a polyol.
1) and a fluorine-containing polyurethane-based protective layer (B) obtained by reacting a curing agent component (b2) containing a fluorine-containing copolymer having a hydroxyl group, with a waterproof structure.

A main component (a1) containing an isocyanate group-terminated polyurethane prepolymer obtained by reacting a polyisocyanate and a polyol, and a curing agent component (a2) containing diethyltoluenediamine as an active hydrogen compound. After the two-component polyurethane waterproofing material (a) is applied to the substrate to form the polyurethane waterproofing layer (A), the aromatic polyurethane is layered on the polyurethane waterproofing layer (A). A two-component type comprising a main component (b1) containing an isocyanate group-terminated polyurethane prepolymer obtained by reacting an isocyanate and a polyol, and a curing agent component (b2) containing a fluorine-containing copolymer having a hydroxyl group. Fluorine-containing polyurethane by applying a fluorine-polyurethane-based protective waterproofing material (b) And forming a protective layer (B), the method of forming the waterproof structure.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The two-component polyurethane waterproofing material (a) used for the waterproofing layer (A) in the present invention will be described. The average number of hydroxyl groups of the polyol used as a raw material of the main component (a1) 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 polyol is preferably composed of a mixture of a diol and a triol, and its weight ratio is preferably 60 to 90/40 to 10. If the molecular weight of the polyol is too small, the elongation of the cured product becomes extremely poor, making it unsuitable for use as a waterproofing material.If the molecular weight is too high, the viscosity of the obtained polyurethane prepolymer increases, and the mechanical strength of the cured product also increases. May be inadequate. The molecular weight per hydroxyl group of the polyol is preferably from 200 to 7000. Preferably it is 500-4000, especially 500-2000, More preferably, it is 700-1500.

Examples of the polyol include a polyoxyalkylene polyol described later, an acylate-based or lactone-based polyester polyol, and a polydiene-based polyol. Of these, polyoxyalkylene polyol is preferable.

The polyoxyalkylene polyol is usually produced by reacting a polyfunctional initiator with a cyclic ether. The initiator referred to herein is an active hydrogen compound having an average number of functional groups of 2 or more, specifically, ethylene glycol,
Examples include polyhydric alcohols such as dipropylene glycol, 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 cyclic ether, ethylene oxide, propylene oxide, 1,2-butylene oxide,
Preferred are alkylene oxides such as 2,3-butylene oxide and styrene oxide, oxetane and tetrahydrofuran. Alkylene oxide is preferred, and propylene oxide alone or a combination of propylene oxide and ethylene oxide is particularly preferred.

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.

Examples of the polyisocyanate as a raw material of the main component (a1) include aromatic polyisocyanates and aliphatic polyisocyanates having an average of two or more isocyanate groups, and modified polyisocyanates obtained by modifying these. Can be Aromatic polyisocyanates are preferred in view of the viscosity, curability, and mechanical strength of the cured coating film of the obtained polyurethane prepolymer. Examples of the aromatic polyisocyanate include tolylene diisocyanate, xylylene diisocyanate, and 4,4′-methylenebis (phenyl isocyanate). Tolylene diisocyanate is preferred and the 2,4-isomer content is 9
Particularly preferred is tolylene diisocyanate at 5% by weight or more.

The isocyanate group-terminated polyurethane prepolymer is preferably produced by reacting a polyisocyanate and a polyol in a nitrogen atmosphere at 80 to 100 ° C. for several hours.

The content of isocyanate groups in the obtained polyurethane prepolymer is preferably 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. 2-4% by weight is 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 polyamine compound occurs in the course of the reaction between the polyamine compound in the curing agent component (a2) and the polyurethane prepolymer, and the polyurethane The reaction with the isocyanate groups in the 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 the unreacted polyisocyanate to 2% by weight or less, it is preferable to carry out the reaction under the condition that the equivalent ratio of NCO group / OH group of the polyisocyanate and the polyol is more than 1.5 and less than 2.1. . If it is not less than 1, the unreacted polyisocyanate content tends to exceed 2% by weight, which is not preferred. On the other hand, if it is less than 1.5, the resulting isocyanate group-terminated polyurethane prepolymer has a high molecular weight, and the viscosity becomes too high, which is not preferable.
More preferably, the equivalent ratio of NCO group / OH group is from 1.8 to
1. React under 95 conditions.

To promote the reaction, tin 2-ethylhexanoate, tin naphthenate, dibutyltin dilaurate,
-A fatty acid metal salt-based catalyst such as zinc ethylhexanoate may be added. Further, the main component (a1) may contain a solvent and other additives.

The curing agent component (a2) contains DETDA as an active hydrogen compound. The content ratio is preferably 10 to 100% by weight of the active hydrogen compound. Further, a polyol or a polyamine other than DETDA may be used in combination as the active hydrogen compound.

As the polyol which can be used in combination, polycaprolactone polyol, polyester polyol, polyoxytetramethylene glycol, polyoxypropylene glycol, polyoxyethylene propylene glycol, castor oil and the like can be used. An amine polyol obtained by adding an alkylene oxide to an aliphatic amine compound can also be used. Preferred examples of the aliphatic amine compound include monoethanolamine, diethanolamine, and ethylenediamine. As the alkylene oxide, propylene oxide and ethylene oxide are preferred. As these polyols, those which are liquid at room temperature and have low viscosity are preferably used.

The polyamines which can be used in combination are
4,4′-containing 4′-methylene-dianiline or a substituent
Methylene-dianiline. 4, including substituents
Examples of 4'-methylene-dianiline include those having a halogen atom as a substituent such as MOCA, and carbon atoms such as 4,4'-methylenebis (2,6-diethylaniline) and 4,4'-methylenebis (2-ethylaniline). Some include 1 to 6 lower alkyl groups as substituents. MOCA
It is preferable not to use those containing a halogen atom as a substituent from the viewpoint of handling, and the like. 4,4′-methylene-dianiline and 4,4′-containing a lower alkyl group substituent
It is particularly preferred to use methylene-dianiline.

The curing agent component (a2) preferably contains a filler. Fillers include calcium carbonate, talc,
Clay, silica, carbon and the like can be mentioned. Calcium carbonate is particularly preferred.

Further, the curing agent component (a2) preferably contains a plasticizer. Examples of the plasticizer include ester plasticizers such as DOP, dibutyl phthalate, dinonyl phthalate, diisononyl phthalate, and dioctyl adipate, chlorinated paraffins, and petroleum plasticizers. Ester plasticizers are particularly preferred. Content is hardener component (a2)
0 to 60% by weight, particularly 10 to 50% by weight is preferred.

The curing agent component (a2) further comprises a pigment, a solvent,
It may contain an additive selected from a catalyst and a stabilizer. 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. Examples of the catalyst include fatty acid metal salts such as tin 2-ethylhexanoate, tin naphthenate, dibutyltin dilaurate, and zinc 2-ethylhexanoate; metal salts composed of tin, cobalt, nickel, iron, zinc, lead, and the like; triethylamine; Dimethylcyclohexylamine, 1,4-diazabicyclo [2.2.2] octane, 1,5-diazabicyclo [4.3.0] nona-
Tertiary amines such as 5-ene, 1,8-diazabicyclo [5.4.0] undec-7-ene and diethylbenzylamine. Also, octanoic acid, naphthenic acid,
An organic acid such as acetic acid may be used. Further, known stabilizers such as antioxidants, ultraviolet absorbers and dehydrating agents can be added. The amount of the additive is not particularly limited, but is generally preferably 40 to 80% by weight in the curing agent component (a2).

The mixing ratio of the main component (a1) and the curing agent component (a2) in the two-pack polyurethane waterproofing material (a) is determined by the isocyanate group (NCO) in the main component (a1).
Group) and the molar ratio [NCO group / (NH ₂ group + OH group)] of the total of amino group and hydroxyl group (NH ₂ group + OH group) in the curing agent component (a2) is 0.8 to 2.0. Is preferred.

Next, a two-component fluorine-containing polyurethane protective waterproofing material (b) used for the protective layer (B) in the present invention.
Will be described.

The main component (b1) contains an aromatic polyisocyanate, an isocyanate group-terminated polyurethane prepolymer obtained by reacting an aromatic polyisocyanate with a polyol, or both.

As the aromatic polyisocyanate, xylylene diisocyanate, tolylene diisocyanate,
4,4'-methylenebis (phenyl isocyanate) and the like are exemplified. Use of this aromatic polyisocyanate has the effect of improving the adhesion between the waterproof layer and the protective layer. When the two-component polyurethane waterproofing material (a) contains a plasticizer, it prevents the tackiness of the surface of the protective layer from increasing due to the plasticizer. A single compound may be used as the aromatic polyisocyanate, or two or more aromatic polyisocyanates may be used as a mixture. Xylylene diisocyanate is particularly preferred because of its excellent weather resistance.

When the main component (b1) contains an isocyanate group-terminated polyurethane prepolymer obtained by reacting an aromatic polyisocyanate and a polyol, the resulting protective layer (B) has improved elasticity and improved flexibility. Can be done.

Examples of the polyol used here include polyols such as polyoxyalkylene polyol and polyester polyol which can be used for the waterproofing material (a).

A polyoxyalkylene polyol is preferred in consideration of the adhesion to the waterproof layer. Particularly preferred are propylene oxide, polyoxyethylene propylene polyol obtained by polymerizing propylene oxide and ethylene oxide, polyoxypropylene polyol, polyoxytetramethylene glycol obtained by polymerizing tetrahydrofuran, and the like. The number of hydroxyl groups is preferably 2 to 4. The molecular weight per hydroxyl group is preferably from 40 to 2,000.

The isocyanate group-terminated polyurethane prepolymer is obtained by converting a polyol and an aromatic polyisocyanate into N
Those obtained by reacting at a molar ratio of CO group / OH group of 1.5 to 2 are preferred. If this ratio exceeds 2, a large amount of free aromatic polyisocyanate remains, which is not preferable in terms of the working environment during coating. The main component (b1) may contain a solvent and other additives.

The curing agent component (b2) contains a fluorine-containing copolymer having a hydroxyl group. Due to having this copolymer, excellent weather resistance is maintained despite that the main component (b1) contains an aromatic polyisocyanate or the like.

Such a fluorine-containing copolymer is not particularly limited as long as it is a copolymer having a hydroxyl group and at least a part of hydrogen atoms bonded to carbon atoms in the main chain are substituted by fluorine atoms. Fluoroolefin copolymers are preferred because of their excellent weather resistance.

The fluoroolefin copolymer can be produced by copolymerizing a fluoroolefin with another monomer. When a fluoroolefin and another monomer are copolymerized, the molar ratio of the fluoroolefin / other monomer in the copolymer is preferably from 40 to 60/60 to 40.

Examples of the fluoroolefin include vinyl fluoride, vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, tetrafluoroethylene, pentafluoropropylene and hexafluoropropylene. Further, compounds containing an oxygen atom such as fluorinated alkyl vinyl ethers can also be used.

Perhaloolefins are particularly preferred. Chlorotrifluoroethylene and tetrafluoroethylene are most preferred because they have good copolymerizability and give a copolymer having excellent weather resistance.

Other monomers that can be copolymerized include vinyl monomers, acrylic monomers, methacrylic monomers, isopropenyl monomers, allyl monomers,
Olefins and the like are exemplified, but vinyl monomers,
Allyl-based monomers and olefins are preferred because they have excellent copolymerizability with fluoroolefins and give copolymers with excellent weather resistance.

Examples of the vinyl monomer include alkyl vinyl ethers such as ethyl vinyl ether, butyl vinyl ether and cyclohexyl vinyl ether, and vinyl carboxylate alkyl esters such as vinyl acetate, vinyl pivalate and vinyl versatate. Examples of the allyl-based monomer include an alkyl allyl ether and a carboxylic acid allyl ester. Examples of the olefin include ethylene, propylene, and isobutylene.

The fluorinated copolymer has a hydroxyl group. The hydroxyl group may be located at any position such as the terminal of the main chain, the direct bond to the main chain, or the terminal of the side chain, but those having a hydroxyl group in the side chain are preferable from the viewpoint of curing reactivity. The hydroxyl group is
It can be introduced by copolymerizing a monomer having a hydroxyl group such as hydroxybutyl vinyl ether, ethylene glycol monoallyl ether, and cyclohexanediol monovinyl ether. Further, a method of introducing a hydroxyl group after polymerization of the monomer, such as a method of copolymerizing vinyl acetate and then saponifying, can also be adopted.

The fluorinated copolymer may have a functional group other than a hydroxyl group (for example, a carboxyl group or an amino group). As the fluorinated copolymer, those commercially available under the name of Lumiflon (Asahi Glass), Zeffle (Daikin Industries), Sefral Coat (Central Glass), Zaffron (Toagosei), Fluonate (Dainippon Ink and Chemicals) are also used. it can.

Further, when it is desired to use a flexible fluoroolefin copolymer, a fluorine-containing copolymer having a relatively long hydroxyl-containing side chain modified with ε-caprolactone, alkylene oxide or the like is used. May be.

The fluorine-containing copolymer has a hydroxyl value of 10 to 10.
0 mgKOH / g is preferred. If the hydroxyl value is too low, the curing is insufficient, the solvent resistance is reduced, and the coating film strength is unfavorably reduced. On the other hand, those having too high a hydroxyl value are not preferred because the elongation of the coating film becomes low and the film cannot follow the expansion and contraction of the waterproof layer and may be torn or peeled off. It is particularly preferred that the hydroxyl value is from 20 to 80.

The fluorinated copolymer has a glass transition temperature (T
_g ) is preferably 40 ° C or lower. If the _Tg is too high, the flexibility of the coating film is impaired, and the protective layer may be broken when the waterproof layer expands and contracts. More preferably, T _g is 3
5 ° C. or less.

Further, a solvent, a pigment, a curing accelerator, various stabilizers and the like may be added to the curing agent component (b2) as required. Also, to add other functions,
A polyol other than the fluorine-containing copolymer having a hydroxyl group may be contained. When such a polyol is contained, the amount to be added is selected in relation to the intended effect, but from the viewpoint of weather resistance, the amount should be 100 parts by weight or less per 100 parts by weight of the fluorine-containing copolymer having a hydroxyl group. Is preferred. Further, such a polyol is preferably an acrylic polyol from the viewpoint of weather resistance.

The mixing ratio of the main component (b1) to the curing agent component (b2) is determined by the isocyanate group (N) in the main component (b1).
The molar ratio (NCO group / OH group) of the hydroxyl group (OH group) in the curing agent component (b2) to the CO group) is preferably 0.8 to 2. If this ratio is too small, curing will be insufficient and the strength of the coating film will decrease, which is not preferable. On the other hand, if it is too large, the coating film is undesirably whitened or the weather resistance is reduced.

In the method for forming a waterproof structure according to the present invention, the two-component polyurethane waterproof material (a) is applied to a substrate to form a polyurethane waterproof layer (A), and then the polyurethane waterproof layer (A) is formed. A) A two-component fluorine-containing polyurethane-based protective waterproofing material (b) is applied to form a fluorine-containing polyurethane-based protective layer (B).

The two-component polyurethane waterproofing material (a) and the two-component fluorine-containing polyurethane protective waterproofing material (b) are constructed as follows.
Each material can be mixed manually or by a static mixer or the like, and can be applied using equipment such as a roller, a ricin gun, or an airless gun.

The waterproof structure of the present invention has excellent characteristics as a waterproof structure of a substrate made of an inorganic material such as concrete, mortar, or metal, particularly a substrate exposed outdoors such as a roof or an outer wall. Further, the material of the base is not limited to the inorganic material, and may be a wood material or a resin material. A resin layer may be formed on a base made of an inorganic material, and then the waterproof structure of the present invention may be formed.
INDUSTRIAL APPLICABILITY The waterproof structure of the present invention can be used for rooftops of buildings, verandas, corridors, floors of exercise facilities, and the like.

The waterproof structure of the present invention has no surface tack and is excellent in weather resistance. Further, the adhesion between the waterproof layer (A) made of the waterproof material (a) and the protective layer (B) made of the protective waterproof material (b) is excellent.

[0054]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The main agent and curing agent used for the waterproofing material and the main agent and curing agent used for the protective waterproofing material are shown below.

Water-proofing material base material 1: Unreacted tolylene diisocyanate content of 2% by weight or less obtained by adding 174 g of tolylene diisocyanate to 800 g of polyoxypropylene diol having a molecular weight of 2,000 and 200 g of polyoxypropylene triol having a molecular weight of 3,000. A polyurethane prepolymer having an isocyanate group content of 3.5% by weight was used as a main agent 1 for a waterproof material.

Curing agent for waterproofing material 1: DETDA (manufactured by Ethyl Corporation, 3,5-diethyltoluene-2,4)
-A mixture of 74 to 80/18 to 24 (weight ratio) of diamine and 3,5-diethyltoluene-2,6-diamine, the same applies hereinafter) 33.7 g, calcium carbonate 550 g, DOP3
26.3 g, xylene 30 g, titanium oxide 50 g and carbon black 10 g were uniformly mixed to obtain a curing agent 1 for a waterproof material.

Hardener 2 for waterproofing material: 7.8 g of 4,4'-methylenebis (2,6-diethylaniline) previously melted by heating in a kneader and 70.2 g of DOP were added thereto, followed by further addition of 4,4. '-Methylenebis (2-ethylaniline) 21.4 g, DETDA 10.5 g, DOP23
0.1 g, calcium carbonate 600 g, titanium oxide 50
g and 10 g of carbon black were charged and uniformly mixed to obtain a curing agent 2 for a waterproof material.

Curing agent 3 for waterproofing material: 32 g of MOCA melted in advance by heating is dissolved in 120 g of polyoxypropylene diol having a molecular weight of 2000, and 500 g of calcium carbonate, 50 g of DOP, 20 g of xylene, 50 g of titanium oxide and 10 g of carbon black are added. Then, the mixture was uniformly mixed to obtain a hardener 3 for a waterproof material.

Main agent for protective waterproofing material 1: 127 g of xylylene diisocyanate in 273 g of polyoxytetramethylene glycol having a molecular weight of 690 (NCO group / OH group = 1.
7) was added thereto, and reacted in a reactor at 70 ° C. for 4 hours. The content of unreacted xylylene diisocyanate was 2% by weight or less,
A polyurethane prepolymer having an isocyanate group content of 5.8% by weight was obtained. To this, 600 g of toluene was added and dissolved to obtain a base material 1 for a protective layer.

Main agent 2 for protective waterproofing material: 294 g of polyoxytetramethylene glycol having a molecular weight of 1000 and 106 g of xylylene diisocyanate (NCO group / OH group = 1.
9) was added, and the reaction was carried out at 70 ° C. for 4 hours in a reactor. The unreacted xylylene diisocyanate content was 2% by weight or less,
A polyurethane prepolymer having an isocyanate group content of 5.6% by weight was obtained. To this, 600 g of toluene was added and dissolved to obtain a base material 2 for protective waterproofing material.

Main agent 3 for protective waterproofing material: 270 g of polyoxytetramethylene glycol having a molecular weight of 1000 and 90 g of xylylene diisocyanate (NCO group / OH group = 1.7)
5) was added, and the reaction was carried out at 70 ° C. for 4 hours in a reactor. The unreacted xylylene diisocyanate content was 2% by weight or less,
A polyurethane prepolymer having an isocyanate group content of 4.7% by weight was obtained. To this, 50 g of a trimethylolpropane adduct of hexamethylene diisocyanate (trade name: Duranate P-301-75E: manufactured by Asahi Kasei Corporation) and 550 g of toluene were added and dissolved to obtain a main agent 3 for a protective waterproofing material.

Main agent 4 for protective waterproofing material: 273 g of polyoxytetramethylene glycol having a molecular weight of 690 and 110 g of tolylene diisocyanate (NCO group / OH group = 1.7)
Was added thereto, and the mixture was reacted at 70 ° C. for 4 hours to obtain a polyurethane prepolymer having an unreacted tolylene diisocyanate content of 2% by weight or less and an isocyanate group content of 6.1% by weight. To this, 600 g of toluene was added and dissolved to obtain a main agent 4 for a protective waterproofing material.

Main agent 5 for protective waterproofing material: 117 g of hexamethylene diisocyanate (NCO group / OH group = 283 g of polyoxytetramethylene glycol having a molecular weight of 690)
1.7) was added thereto, and the mixture was reacted at 80 ° C. for 5 hours in a reactor to obtain a polyurethane prepolymer having an isocyanate group content of 5.8% by weight. To this, 600 g of toluene was added and dissolved to obtain a base material 5 for a protective waterproofing material.

Curing agent for protective waterproofing material 1: fluorinated copolymer having a hydroxyl group copolymerized with tetrafluoroethylene / ethyl vinyl ether / hydroxybutyl vinyl ether (hydroxyl value 52 mg KOH / g, T _g 5 ° C., number average molecular weight 16,000) Xylene solution (solids concentration 50%)
To 606 g, 242.5 g of titanium oxide, 18.2 g of carbon black, 12.1 g of a 10000-fold diluted solution of dibutyltin dilaurate in xylene, and 121.2 g of xylene
g was added and uniformly mixed to obtain a hardener 1 for a protective waterproofing material.

Curing agent 2 for protective waterproofing material: fluorinated copolymer having a hydroxyl group copolymerized with chlorotrifluoroethylene / ethyl vinyl ether / hydroxybutyl vinyl ether (hydroxyl value 50 mg KOH / g, T _g 25 ° C., number average molecular weight 20,000) ) In xylene solution (solids concentration 5
0% by weight) 606 g of titanium oxide 242.5 g, carbon black 18.2 g, dibutyltin dilaurate 1
12.1 g of a 0000-fold xylene diluted solution and 121.2 g of xylene were added and uniformly mixed to obtain a hardener 2 for a protective waterproofing material.

Curing agent 3 for protective waterproofing material: Fluorinated copolymer having a hydroxyl group obtained by copolymerizing chlorotrifluoroethylene / ethyl vinyl ether / hydroxybutyl vinyl ether (hydroxyl value 50 mg KOH / g, T _g 25 ° C., number average molecular weight 20,000) ) In xylene solution (solids concentration 5
(0% by weight) 182 g of a toluene solution (solid content concentration: 50% by weight) of 424 g of an acrylic copolymer (having a hydroxyl value of 32 mg KOH / g) obtained by copolymerizing styrene / n-butyl acrylate / 2-hydroxyethyl methacrylate; 0.5 g, 18.2 g of carbon black, 12.1 g of a 10000-fold diluted solution of dibutyltin dilaurate in xylene and 121.2 g of xylene were uniformly mixed to obtain a hardener 3 for a protective waterproofing material.

Curing agent 4 for protective waterproofing material: Acrylic copolymer obtained by copolymerizing styrene / n-butyl acrylate / 2-hydroxyethyl methacrylate (having a hydroxyl value of 32 mg)
KOH / g) toluene solution (solid content concentration 50% by weight)
606 g, 242.5 g of titanium oxide, 18.2 g of carbon black, 12.1 g of a 10000-fold diluted solution of dibutyltin dilaurate in xylene, and 121.2 g of xylene
g was added and uniformly mixed to obtain a hardener 4 for a protective waterproofing material.

[Examples (Examples 1 to 8) and Comparative Examples (Example 9)
11)] As the waterproofing material, a waterproofing layer was formed by using the combination of the main agent and the curing agent shown in Table 1 in a ratio of NCO group / (OH group + NH ₂ group) (molar ratio) of 1.5. .
Further, as a protective waterproofing material, a protective layer is formed by using a combination of the main agent and the curing agent shown in Table 1 in a ratio where the NCO group / OH group (molar ratio) becomes the molar ratio shown in the table. did. Each example was evaluated according to the following method. Table 1 shows the evaluation results.

Surface tack: Applying a waterproof material to the substrate,
After leaving at 24 ° C. for 24 hours, a protective waterproofing material was applied. After leaving at 20 ° C. for 24 hours, the surface tack was observed by finger touch.な し indicates no tack, and x indicates markedly tack.

Adhesion: Apply a waterproofing material to the substrate, leave it at 20 ° C. for 24 hours, apply a protective waterproofing material,
After standing for 4 hours, evaluation was performed according to JIS-K5400 8.5.2.

Weather resistance: A waterproof material was applied to the substrate, left at 20 ° C. for 24 hours, and then a protective waterproof material was applied.
After standing for 4 hours, the gloss was measured after performing a test using a sunshine carbon arc lamp system of JIS-K5400 9.8.1 for 3000 hours. ◎: 80% or more, 以上: 60% or more, ×: Less than 60%

[0072]

[Table 1]

[0073]

According to the waterproof structure of the present invention, even when the two-component polyurethane waterproofing material (a) used for the waterproofing layer (A) contains a relatively large amount of plasticizer, there is no particular tackiness on the surface. Thus, a waterproof structure having excellent weather resistance is obtained. The adhesiveness between the waterproof layer (A) made of the waterproof material (a) and the protective layer (B) made of the protective waterproof material (b) is also excellent. Further, without using the conventionally used MOCA, physical properties equivalent to or higher than the conventional one can be exhibited.

Claims (3)

[Claims] 1. A main component (a1) containing an isocyanate group-terminated polyurethane prepolymer obtained by reacting a polyisocyanate and a polyol, and a curing agent component (a2) containing diethyltoluenediamine as an active hydrogen compound. And a main component (b1) containing an isocyanate group-terminated polyurethane prepolymer obtained by reacting an aromatic polyisocyanate and / or an aromatic polyisocyanate with a polyol; And a fluorinated polyurethane-based protective layer (B) obtained by reacting a curing agent component (b2) containing a fluorinated copolymer having a hydroxyl group. 2. A main component (a1) containing an isocyanate group-terminated polyurethane prepolymer obtained by reacting a polyisocyanate and a polyol, and a curing agent component (a2) containing diethyltoluenediamine as an active hydrogen compound. A polyurethane waterproof layer (A) is formed by applying a two-component polyurethane waterproof material (a) made of the following on a substrate, and then an aromatic polyisocyanate and / or fragrance is formed on the polyurethane waterproof layer (A). Component consisting of a main component (b1) containing an isocyanate group-terminated polyurethane prepolymer obtained by reacting an aromatic polyisocyanate and a polyol, and a curing agent component (b2) containing a fluorine-containing copolymer having a hydroxyl group. Fluorine-containing polyurethane by applying a type fluorine-containing polyurethane protective waterproofing material (b) And forming a protective layer (B), the method of forming the waterproof structure. 3. The method according to claim 2, wherein the two-part polyurethane waterproofing material (a) contains a plasticizer in the curing agent component (a2).