JP2001311264A - Laminated waterproof structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To overcome a problem of easy deposition of dust in the air on an extensible surface layer of a conventional waterproof layer for a building, though the surface layer which is formed of an extensible material improves the weatherability of the entire waterproof layer and imparts a hue to the appearance of the building, thereby suppressing degraded appearance due to contamination, and to provide a laminated structure which is prevented from degradation of outward design value due to contaminant, has lamination of a surface layer capable of following the extensibility of a waterproof material, and can maintain the waterproofing performance over a long period of time in spite of the contaminant on the surface layer which functions as a heat storage area of near infrared rays, extremely raises the temperature of the waterproof material, and accelerates degradation of the waterproof layer, thereby forming factors inducing expansion and cracks. SOLUTION: A coat with a contact angle of 70 deg. or less with respect to water on the surface and an expansion ratio of 50 to 250% is laminated on the surface of the waterproof material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a waterproof function for preventing rainwater from entering the inside of a building on a roof or a roof of a building for a long period of time, and also has an effect of maintaining its aesthetic appearance. It relates to a laminated waterproof structure.

[0002]

2. Description of the Related Art Conventionally, in a building, a waterproof layer is provided on a roof or a roof in order to prevent moisture from entering into the inside of the building due to rainfall. Since such a waterproof layer needs to be able to follow the displacement accompanying the expansion and contraction of the frame, the shaking of the building, and the like, a layer having a relatively large elongation is used. Usually, such a waterproof layer has a surface layer, and this surface layer plays a role of improving the weather resistance of the entire waterproof layer and giving a hue of appearance. Such a top coat naturally follows a stretch of the waterproof layer, and therefore, a relatively stretchable material is used. However, such a surface layer having a large elongation is apt to be adhered to dust in the air, and often causes poor appearance due to contamination.

[0003]

However, when a material having low elongation is used as the surface layer in order to make the surface of the waterproof layer less likely to adhere to the surface, the problem of contamination can be improved. In some cases, it is impossible to follow the expansion and contraction of the waterproof material, and cracks may occur in the surface layer. On the other hand, the waterproof layer is constantly exposed to changes in temperature due to rainfall, sunshine, and seasons, and must always maintain waterproof performance under extremely severe environmental changes. However, it has been found that the presence of contaminants in the surface layer as described above promotes deterioration of the waterproof layer and causes swelling and cracks. That is, such a contaminant has a very high ability to absorb infrared rays in sunlight, and as a result, the contaminant acts as a heat storage field, resulting in a significant increase in the temperature of the waterproof material.

[0004] Accordingly, the problem to be solved by the present invention is to laminate a surface material that can follow the expansion and contraction of the waterproof material without causing a reduction in the design of the appearance due to such contaminants.
The purpose is to obtain a laminated structure that can sustain the waterproof performance over a long period of time.

[0005]

[Means for Solving the Problems]

Therefore, the inventors of the present invention have proposed a method of laminating a surface layer which has a property that such contaminants hardly adhere to the existing waterproof material and which can follow expansion and contraction of the waterproof material. As a result, the present invention has been completed.

That is, the present invention provides: A laminated waterproof structure, wherein a coating film having a surface contact angle with water of 70 ° or less and an elongation percentage of 50 to 250% is laminated on the surface of the waterproof material.

[0008] 2. A coating film having a surface contact angle of 70 ° or less with water and an elongation percentage of 50 to 250% is formed of Si (OR ₁ ) (OR ₂ ) (OR ₃ ) (OR ₄ ) (R ₁ , R ₂ , R ₃ and R ₄ are formed from a coating composition containing a tetraalkoxysilane represented by the same or different alkyl group having 1 to 12 carbon atoms and / or a condensate thereof. Do 1. 2. The laminated waterproof structure according to 1.

3. A coating film having a surface contact angle of 70 ° or less with water and an elongation percentage of 50 to 250% is a condensate of tetraalkoxysilane having an average degree of condensation of 4 to 20, and an alkyl group in the condensate is Carbon number 1-2 and carbon number 3
And 10 to 10 are mixed, and the mixing ratio is formed from a coating composition containing a compound in which an alkyl group having 3 to 10 carbon atoms is 5 to 50% of all alkyl groups in the condensate. It is characterized in that: 2. The laminated waterproof structure according to 1.

[0010] 4. A coating film having a contact angle of water of 70 ° or less on the surface and an elongation percentage of 50 to 250% was prepared by the method (A).
The weight average molecular weight is 5000 to 80000, and the hydroxyl value is 2
A coating composition containing 0 to 150 KOH mg / g of a polyol, (B) a polyisocyanate compound, and (C) a tetraalkoxysilane condensate. ) A polyisocyanate compound in an NCO / OH ratio of 0.6 to 1.4, and (C) a condensate of tetraalkoxysilane having an average degree of condensation of 4 to 20, wherein the alkyl in the condensate is Groups having 1 to 2 carbon atoms and 3 to 10 carbon atoms are mixed, and the mixing ratio is such that alkyl groups having 3 to 10 carbon atoms are 5 to 50% of all alkyl groups in the condensate. It is formed from a coating composition characterized by containing 1.0 to 40.0 parts by weight of a certain compound in terms of SiO ₂ . Or 3. 2. The laminated waterproof structure according to 1.

5. A coating film having a surface contact angle of 70 ° or less with water and an elongation percentage of 50 to 250%,
(A ′) a solubility parameter (hereinafter referred to as “SP value”) of 6.5 to 9.5 and a weight average molecular weight of 5000 to 1
50,000, a hydroxyl value of 15 to 100 KOH mg / g, and a resin solid content of 100 parts by weight of a polyol dissolved and / or dispersed in a non-aqueous solvent,
(B ′) containing a polyisocyanate compound in an NCO / OH ratio of 0.7 to 2.0, and (C ′)
It is a condensate of tetraalkoxysilane having an average degree of condensation of 4 to 20, wherein the alkyl group in the condensate is a mixture of those having 1 to 3 carbon atoms and 4 to 12 carbon atoms, and the mixture ratio is carbon. A coating composition comprising 1.0 to 50.0 parts by weight, in terms of SiO ₂ , of a compound in which the alkyl groups of Formulas 4 to 12 are 5 to 50% of the total alkyl groups in the condensate. It is characterized by being formed.
3. The laminated structure according to item 1. Is included.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail. The present invention is a laminated structure including at least two layers formed of a waterproof material and a surface coating layer.

First, it is possible to use a coating film waterproofing material as the waterproofing material. Here, the coating film waterproof material is a liquid waterproof rubber or resin material that is applied on site with a brush, a spatula, a roller, or applied by a spraying machine to form a film and harden to form a seamless waterproof layer. It is a material used for the construction method. Specifically, in JISA 6021, urethane rubber type, chloroprene rubber type, rubber asphalt type, and acrylic rubber type are classified according to the main raw materials, but in addition, acrylic resin type, polyester type, epoxy type, Ethylene-vinyl acetate and the like are also included. In addition, a waterproofing material composed of two components, a polymer emulsion and a cement-based powder, which is generally called a hydrated solidification type coating film waterproofing material, hydrates the water in the emulsion with the polymer and cement by mixing both. Those which form a hardening and waterproofing layer by a reaction are also included. In particular, urethane rubbers are preferably used in consideration of coating film strength and waterproof performance. These materials can be applied in a dry film thickness of 1 to 4 mm, preferably 1.5 to 3 mm, and open roof corridors of buildings,
It is installed as a waterproof material on a veranda or the like. 1m dry film thickness
If it is less than m, the waterproof performance is not sufficiently exhibited, and if it is more than 4 mm, performance commensurate with cost cannot be expected. Further, the elongation percentage of the waterproof material is not particularly limited, but is preferably 450 to 1300% in a standard state according to JISA 6021, more preferably 500%.
It is desirable that the amount be within 1000%.

According to the laminated structure of the present invention, appropriate treatments such as a base adjustment material and a primer are performed according to the type of the base to be applied, a waterproof material is applied, and a surface coating layer is laminated. In addition, a known reinforcing material and underlay cushioning material can be used.

Further, the laminated structure of the present invention includes a case in which a coating film having the specific performance of the present invention is formed on an existing waterproof layer as a renovation work after a certain period has already been applied as a waterproof layer. It is. In this case, the surface coating layer can be laminated on the existing waterproof layer, or the surface coating layer can be laminated after newly applying the waterproof layer. In addition, if necessary, appropriate treatments such as a base adjustment material and a primer can be performed.

Next, the surface coating layer which is another component of the present invention will be described. In the present invention, the contact angle of the surface with water of 70 ° or less means that the coated paint is dried and hardened, and immediately after forming the coating film, the contact angle of the surface with water becomes 70 ° or less, After the coated paint has dried and cured and formed the coating film, the components of the coating film surface react in a relatively short period of time (generally within 2 weeks to 1 month) due to atmospheric moisture, dew condensation water, rain water, etc. And those having a surface contact angle with water of 70 ° or less.

In the present invention, the contact angle of the surface with water is set to 70 ° or less (preferably 45 ° or less, more preferably 40 ° or less) because the coating film having such surface characteristics is used in the atmosphere. This is because, even when contaminants such as dust adhere, mainly lipophilic contaminants are washed away by rainwater from rainfall. Such a low-contamination type coating film functions such an effect basically by making the coating film surface hydrophilic. Accordingly, the coating composition for forming the low-contamination type coating film is not particularly limited as long as it makes the coating film surface hydrophilic. For example, a polymer having a hydrophilic group or a hydrophilic segment may be used in an aqueous system. Used as a solvent-based film-forming binder. A component that imparts hydrophilicity after the formation of a coating film is mixed with a general aqueous or solvent-based binder. And the like.

Examples of the hydrophilic group include a hydroxyl group, a carboxyl group, an amino group and an amide group, and examples of the hydrophilic segment include segment structures of polyalkylene oxide, polyoxazoline and polyamide. As the hydrophilicity imparting component, Si (OR ₁ ) (OR ₂ ) (OR ₃ ) (OR ₄ ) (R ₁ , R ₂ , R ₃ , R ₄ is the same or different alkyl having 1 to 12 carbon atoms. Group) and / or a condensate thereof.

Generally, tetraalkoxysilane is mixed in a binder for forming a coating film, and is localized on the surface of the coating film during the formation of the coating film. At this time, as in Chemical Formula 1,
Immediately after the formation of the coating film, it undergoes a hydrolysis reaction with moisture in the air to generate silanol groups, renders the surface of the coating film hydrophilic, and reduces the contact angle with water to 70 ° or less. In addition, even after the formation of the coating film, this reaction proceeds due to moisture and rain in the air over time, and the contact angle of the coating film surface with water becomes a lower value. At this time, it is particularly preferable that the functional group of the tetraalkoxysilane condensate has a partially different number of carbon atoms because of the ease of localization on the coating film surface and the early development of surface hydrophilicity. For example, it is a condensate of tetraalkoxysilane having an average degree of condensation of 4 to 20, wherein the alkyl group in the condensate is a mixture of one having 1 to 2 carbon atoms and 3 to 10 carbon atoms. Is preferably used, wherein the alkyl group having 3 to 10 carbon atoms is 5 to 50% of the total alkyl group in the condensate.

[0020]

Embedded image

As the coating composition containing such a tetraalkoxysilane, an existing one such as an acrylic resin, an acrylic silicon resin, a urethane resin, or a fluororesin can be used as a binder for forming a coating film. These may be water-based or solvent-based, and in the solvent-based system,
Weak solvent-based solvents mainly containing aliphatic hydrocarbon solvents can also be used.

Particularly preferred embodiments include: (1) (A) a weight average molecular weight of 5,000 to 80,000;
A polyol having a hydroxyl value of 20 to 150 KOH mg / g,
A coating composition comprising (B) a polyisocyanate compound and (C) a tetraalkoxysilane condensate,
(A) For 100 parts by weight of the resin solid content of the polyol,
(B) a polyisocyanate compound in an NCO / OH ratio of 0.6 to 1.4, and (C) a condensate of tetraalkoxysilane having an average degree of condensation of 4 to 20. Is an alkyl group having 1 to 2 carbon atoms and 3 carbon atoms
And a mixture in which the alkyl group having 3 to 10 carbon atoms is 5 to 50% of the total alkyl groups in the condensate is 1.0% in terms of SiO _2.
To 40.0 parts by weight, or

(2) (A ') SP value is 6.5 to 9.5,
(B ′) polyisocyanate having a weight average molecular weight of 5,000 to 150,000, a hydroxyl value of 15 to 100 KOH mg / g, and a resin solid content of 100 parts by weight of a polyol dissolved and / or dispersed in a non-aqueous solvent; A compound having an NCO / OH ratio of 0.7 to 2.0, and a condensate of (C ′) tetraalkoxysilane having an average degree of condensation of 4 to 20, wherein the alkyl group in the condensate is Compounds in which those having 1 to 3 carbon atoms and 4 to 12 carbon atoms are mixed, and the mixing ratio of the alkyl groups having 4 to 12 carbon atoms is 5 to 50% of the total alkyl groups in the condensate Is contained in an amount of 1.0 to 50.0 parts by weight in terms of SiO ₂ .

(A) Polyol means a polyol generally used in the technical field of polyurethane, particularly in the technical field of polyurethane resin paint, and forms a coating film by mixing and reacting with a polyisocyanate compound as a curing agent. It is the main element.

Examples of such polyols include polyether polyols, polyester polyols, and acrylic polyols. Hereinafter, each polyol will be exemplified.

Examples of the polyether polyol include one or more polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, trimethylolpropane, pentaerythritol, glucose, sorbitol, and sucrose. Polyols obtained by adding one or more of oxide, ethylene oxide, butylene oxide, styrene oxide and the like, and polyoxytetramethylene polyol obtained by adding tetrahydrofuran to the polyhydric alcohol by ring-opening polymerization Can be exemplified.

Examples of the polyester polyol include one or more of ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, cyclohexanedimethanol, glycerin, trimethylolpropane, pentaerythritol and other low molecular weight polyhydric alcohols. Polycondensation with glutaric acid, adipic acid, pimelic acid, speric acid, sebacic acid, terephthalic acid, isophthalic acid, dimer acid, hydrogenated dimer acid or other low-molecular dicarboxylic acid or oligomeric acid; Examples thereof include polyols such as a ring-opening polymer of a ring-opening ester such as coalesce, propiolactone, caprolactone, and valerolactone.

In the acrylic copolymer, β-hydroxyethyl acrylate, β-hydroxypropyl acrylate, 3-hydroxypropyl acrylate, β-hydroxybutyl acrylate, 4-hydroxybutyl acrylate, β-hydroxybutyl acrylate Hydroxyalkyl esters of acrylic acid such as hydroxypentyl or similar hydroxyalkyl esters of methacrylic acid; furthermore, glycerin, acrylate monoesters of polyhydric alcohols such as trimethylolpropane or methacrylic monoesters similar thereto, N-methylol acrylamide Alternatively, an acrylic polyol having two or more hydroxyl groups in one molecule such as a copolymerized monomer of a monoethylenically unsaturated monomer having a hydroxyl group such as N-methylol methacrylamide can be used.

Other examples include phenolic resin polyols, epoxy polyols, polybutadiene polyols, polyisoprene polyols, polyester-polyether polyols, polymer polyols obtained by adding or dispersing polymers such as acrylonitrile and styrene, urea-dispersed polyols and carbonate polyols. It can be used as the polyol of the present invention. In particular, in consideration of the weather resistance of a coating film formed from the composition of the present invention, it is desirable to use an acrylic polyol.

The (A ′) polyol component is dissolved or dispersed in a non-aqueous solvent.
Dissolved polyols can be classified into two types, dissolved polyols, and dispersed polyols are non-aqueous dispersion type (hereinafter, referred to as "NAD type") polyols.

The soluble polyol is soluble in a non-aqueous solvent, and is specifically a polyol having two or more hydroxyl groups in one molecule, for example, alkyd polyol, acrylic polyol, acrylated polyol. Examples include alkyd polyols, polyester polyols, and polybutadiene oligomers. Suitable for dissolving in a non-aqueous solvent, the form of the polyol having an SP value of 6.5 to 9.5 is selected from alkyd polyols having an oil length of 40% or more, or solvents such as pt-butyl benzoic acid. Alkyd polyols containing raw materials with high affinity,
An acrylic polyol containing a raw material having a high affinity for a solvent having a low solubility such as isobutyl methacrylate and 2-ethylhexyl methacrylate can be given.

The NAD-type polyol is dispersed as resin particles in a non-aqueous solvent, and has both a resin portion soluble in a non-aqueous solvent and a resin portion not soluble in a non-aqueous solvent. The resin portion soluble in a non-aqueous solvent is one having a solubility in a non-aqueous solvent of 99.0% by weight or more. This depends on the type of the non-aqueous solvent, and may be any as long as it can be dissolved in the non-aqueous solvent to be finally dispersed. Conversely, the resin portion that does not dissolve in the non-aqueous solvent is one that does not dissolve in the non-aqueous solvent at all or has a very small amount (for example, the solubility is less than 1.0% by weight). Since this also depends on the type of the non-aqueous solvent, one that hardly dissolves in the non-aqueous solvent to be finally dispersed is used. As a specific example,
NA using acrylic resin as soluble resin part
And D-type polyols.

In the present invention, a soluble polyol or an NAD polyol can be used alone or in combination as the component (A ').

The SP value of the component (A ') is 6.5 to 9.5.
However, by using such an SP value, it becomes possible to dissolve and / or disperse even in a solvent having a weak dissolving power called a weak solvent, so that a weak solvent type paint can be obtained. it can. Of course, it is also possible to use it after dissolving it in a strong solvent having a strong dissolving power.

The non-aqueous solvent includes all solvents other than water that can be used for polyols, and common solvents include organic solvents. Examples of the organic solvents include aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, esters, ketones, and the like. As the aliphatic hydrocarbon solvent, for example, n-hexane, n-pentane, n
-Octane, n-nonane, n-decane, n-undecane, n-dodecane, terpine oil, mineral spirit and the like can be exemplified. Examples of the aromatic hydrocarbon solvent include toluene, xylene, and solvent naphtha. Examples of other solvents include ethyl acetate, butyl acetate, methyl ethyl ketone, and methyl isobutyl ketone. Among such non-aqueous solvents, one or two
Any combination of more than one species may be used.

In any of (A) and (A '), the above-mentioned polyol can be used as a fluorine-containing polyol obtained by copolymerizing a fluorine-containing monomer as a constituent component.

As a component of the coating material of the present invention, it is also preferable to add an amine compound to the polyol (A) or (A '). By using such an amine compound,
In addition to the above-mentioned contamination prevention effect, the recoating property is further improved, and even when multi-layer coating is performed, blisters and cracks due to aging change are generated, and the occurrence of lifting when coating the second layer or more is effectively performed. In addition to the above, a strong coating film can be formed, and a non-staining coating film having excellent durability can be obtained. Further, a compound having a tertiary amino group in the polyol component may be used instead of the amine compound. By using such a polyol, the same effect as when an amine compound is added can be obtained.

In the present invention, an alkoxysilyl group-containing acrylic copolymer (A ″) can be used as the component (A). The alkoxysilyl group-containing acrylic copolymer has the general formula

[0039]

Embedded image

A polymer having at least one, and preferably two or more, alkoxysilyl groups represented by the following formula: This alkoxysilyl group may be contained in the terminal or the side chain of the main chain of the component (A ''), or may be contained in both.

In the formula, R ₅ is a group having 1 to 1 carbon atoms.
0, preferably 1-4 alkyl groups

[0042] Specific examples of the alkyl group represented by R ₅ include methyl group, ethyl group, n- propyl group, an isopropyl group, n- butyl group, isobutyl group and the like. In the above formula, R ₆ is a hydrogen atom or a carbon number 1 to
10, preferably a monovalent hydrocarbon group selected from the group consisting of 1 to 4 alkyl groups, aryl groups, and aralkyl groups.

In the hydrocarbon group represented by R ₆ , specific examples of the alkyl group include the same groups as R ₅ .
Specific examples of the aryl group include, for example, a phenyl group, and specific examples of the aralkyl group include, for example, a benzyl group. Specific examples of the alkoxysilyl group represented by Chemical Formula 2 include, for example, a group contained in an alkoxysilyl group-containing monomer described below.

The component (A ″) is excellent in weather resistance, chemical resistance, water resistance and the like of the cured product because the main chain is substantially composed of an acrylic copolymer chain. further,
In the component (A ″), if the alkoxysilyl group is bonded to a carbon atom, the cured product obtained will have even more excellent water resistance, as well as excellent alkali resistance and acid resistance. Further, the number average molecular weight of the component (A ″) is preferably from 1,000 to 50,000 from the viewpoint of physical properties such as durability of a cured product obtained from the composition of the present invention, and is preferably 30 to 50,000.
00-25000 is more preferable.

The component (A ″) can be obtained by copolymerizing an acrylic monomer such as acrylic acid, methacrylic acid, or a derivative thereof with an alkoxysilyl group-containing monomer.

The acrylic monomer is not particularly limited, and specific examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,
Stearyl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, trifluoroethyl (meth) acrylate, pentafluoropropyl (meth) acrylate, perfluorocyclohexyl (meth) acrylate, (meth) acrylonitrile, glycidyl (meth) ) Acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, methacrylamide, α-ethylmethacrylamide, N-butoxymethylmethacrylamide, N, N-dimethylacrylamide, acryloylmorpholine, 2-hydroxyethyl (meth) A) acrylate, 2-hydroxypropyl (meth) acrylate, N
A vinyl ester containing a phosphate ester group which is a condensation product of a hydroxyalkyl ester of an α, β-ethylenically unsaturated carboxylic acid such as a methylalkyl methacrylamide or a hydroxyalkyl ester of acrylic acid with a phosphoric acid or a phosphoric acid ester; And a (meth) acrylate containing a urethane bond or a siloxane bond.

The alkoxysilyl group-containing monomer is not particularly limited except that it has a polymerizable double bond. Specific examples thereof include, for example,

[0048]

Embedded image

[0049]

Embedded image

And acrylate or methacrylate having an alkoxysilyl group at the terminal via a urethane bond or a siloxane bond.

In the present invention, the polyisocyanate (B) is toluene diisocyanate (TDI), 4,4-
Diphenylmethane diisocyanate (pure-MD
I), polymeric MDI, xylylene diisocyanate (XDI), hexamethylene diisocyanate (HM)
DI), isophorone diisocyanate (IPDI), hydrogenated XDI, hydrogenated MDI, and other isocyanate monomers by allophanate, biuret, dimerization (uretidione), trimerization (isocyanurate), adduct, carbodiimidization, etc. , Derivatized forms, and mixtures thereof can be used. In particular, in consideration of yellowing of a formed coating film, it is preferable to use an aliphatic or alicyclic polyisocyanate or a mixture thereof. Further, these polyisocyanates can also be used in the form of blocked isocyanates using blocking agents such as alcohols, phenols, ε-caprolactam, oximes, and active methylene compounds.

The polyisocyanate (B ') of the present invention may be any of the following: Bernock DN-990, DN-999, DN-9
-992 (both manufactured by Dainippon Ink and Chemicals, Inc.), Duranate TSA (manufactured by Asahi Kasei Corporation), Takenate D-177N (manufactured by Takeda Pharmaceutical Co., Ltd.), Desmodur Z-4270 (manufactured by Sumitomo Bayer Urethane Co., Ltd.) And the like. These curing agents can be suitably used because they dissolve in a solvent having a low dissolving power. Others
Toluene diisocyanate (TDI), 4,4-diphenylmethane dissocyanate (pure-MDI), polymeric MDI, xylylene diisocyanate (XD
I), hexamethylene diisocyanate (HMDI),
Isophorone diisocyanate (IPDI), hydrogenated XD
I. Derivatized isocyanate monomer such as hydrogenated MDI or the like by allohanate, biuret, dimerization (uretidion), trimerization (isocyanurate), adduct, carbodiimide reaction, etc., or a mixture thereof has strong dissolving power. It is also possible to use it after dissolving it in a solvent. As for the solvent for dissolving the component (B ′),
The same solvents as those exemplified for the non-aqueous solvent of the component (A ') can be used. Further, these components (B ′) can be used in the form of a blocked isocyanate using a blocking agent such as alcohols, phenols, ε-caprolactam, oximes, and active methylene compounds. These are also preferably used as a solution with a solvent.

In the present invention, when the aforementioned (A ″) is used, a catalyst (B ″) for hydrolysis and condensation of an alkoxysilyl group is used. Specific examples of this (B ″) include dibutyltin dilaurate, dibutyltin dimaleate,
Dioctyltin dilaurate, dioctyltin dimalate,
Organic tin compounds such as tin octylate, phosphoric acid such as phosphoric acid, monomethyl phosphate, monoethyl phosphate, monobutyl phosphate, monooctyl phosphate, monodecyl phosphate, dimethyl phosphate, diethyl phosphate, dibutyl phosphate, dioctyl phosphate, and didecyl phosphate Esters, propylene oxide, butylene oxide, cyclohexene oxide, glycidyl methacrylate, glycidol, acrylic glycidyl ether, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, Epoxy compound and phosphoric acid and / or
Or an addition reaction product with a monoacid phosphate, maleic acid, adipic acid, azelaic acid, sebacic acid, itaconic acid, citric acid, succinic acid, phthalic acid, trimetic acid,
Acidic compounds such as pyrometic acid, acid anhydrides thereof, p-toluenesulfonic acid and the like can be mentioned.

Further, a mixture or a reaction product of the acidic catalyst and the amine is also included. For example, hexylamine,
N. Amines such as N-dimethyldodecylamine and dodecylamine are exemplified, and an organic tin compound is preferable, and a malate-based organic tin compound is more preferably used because it is particularly excellent in hydrophilicity of a coating film surface in an early stage of coating film formation. .

The (C) tetraalkoxysilane condensate of the present invention comprises Si (OR ₁ ) (OR ₂ ) (OR ₃ ) (OR ₄ ) (R ₁ , R ₂ , R ₃ , and R ₄ have 1 to 1 carbon atoms) It can be produced by one or more kinds of tetraalkoxysilanes represented by the same or different alkyl groups (the same 10 different alkyl groups) by the method described below, but is not limited thereto. As a result, of the total alkyl groups, about 5 to 5
It is sufficient that 0 equivalent% is an alkyl group having 3 to 10 carbon atoms and a condensate having a weight average molecular weight of 250 to 3500.

As the raw material tetraalkoxysilane, a tetraalkoxysilane having at least one alkyl group having 1 or 2 carbon atoms and one alkyl group having 3 to 10 carbon atoms are used.
A tetraalkoxysilane having at least one kind or a tetraalkoxysilane having at least one kind of an alkyl group having 1 or 2 carbon atoms and at least one kind of an alkyl group having 3 to 10 carbon atoms is used. Any of the methods of condensing according to the method described above.

Specific examples of the alkoxysilane compound having an alkyl group having 3 to 10 carbon atoms used as a raw material for producing the tetraalkoxysilane condensate used in the present invention include monobutoxytrimethoxysilane and monopropoxytrimethoxysilane. And condensates such as monopentoxytrimethoxysilane, monohexoxytrimethoxysilane and dibutoxydiethoxysilane, but are not limited thereto. Examples of the tetraalkoxysilane having 1 or 2 carbon atoms include tetramethoxysilane and tetraethoxysilane.

On the other hand, one or more kinds of tetraalkoxysilanes comprising an alkyl group having 1 to 2 carbon atoms are condensed by a known method so as to have a degree of condensation of 4 to 20, and then a mixture having 3 carbon atoms is obtained.
It is also possible to employ a method of transesterifying about 5 to 50% of the alkyl group portion of the condensate using a method of transesterification with an alcohol having an alkyl group of 10 to 10.

As for the (C ′) tetraalkoxysilane condensate of the present invention, Si (OR ₁ ) (OR ₂ ) (OR ₃ ) (OR ₄ ) (R ₁ , R ₂ , R ₃ and R ₄ can be produced by using at least one kind of tetraalkoxysilane represented by the same or different alkyl group having 1 to 12 carbon atoms as a raw material by the method described below. There is, but is not limited to this. As a result, of the total alkyl groups, about 5 to 5
It is sufficient that 0 equivalent% is an alkyl group having 4 to 12 carbon atoms and a condensate having a weight average molecular weight of 250 to 3500.

As the raw material tetraalkoxysilane, tetraalkoxysilane having at least one alkyl group having 1 to 3 carbon atoms and tetraalkoxysilane having at least one alkyl group having 4 to 12 carbon atoms are used, or
One or more alkyl groups having 1 to 3 carbon atoms and 4 to 1 carbon atoms
Any method may be used in which a tetraalkoxysilane having at least one of the two alkyl groups is used and condensed by a known method.

Specific examples of the alkoxysilane compound having an alkyl group having 4 to 12 carbon atoms used as a raw material for producing the tetraalkoxysilane condensate used in the present invention include monobutoxytrimethoxysilane and monopropoxytrimethoxysilane. And condensates such as monopentoxytrimethoxysilane, monohexoxytrimethoxysilane and dibutoxydiethoxysilane, but are not limited thereto. Examples of the tetraalkoxysilane having 1 or 2 carbon atoms include tetramethoxysilane and tetraethoxysilane.

On the other hand, at least one kind of tetraalkoxysilane comprising an alkyl group having 1 to 3 carbon atoms is condensed by a known method so as to have a degree of condensation of 4 to 20, and then the compound having 4 carbon atoms is obtained.
A method in which about 5 to 50% of the alkyl group portion of the condensate is transesterified using a method of transesterification with an alcohol having an alkyl group of from 12 to 12 may be employed.

[0063] (A), (B), (C), or (A '), (B' ), the mixing ratio of (C ') component is as defined above, wherein in terms of SiO ₂ value Is
All Si contained in the above-mentioned alkoxysilanes is SiO
It is a weight when it is assumed to be ₂ , and the actual calculation is that after completely hydrolyzing these compounds having Si-O bonds such as alkoxysilanes and silicates, 9
The residual silica ratio (% by weight) remaining as silica (SiO ₂ ) when calcined at 00 ° C. was measured, and the measurement was performed based on the following equation. [SiO ₂ equivalent value] = [X] × [silica remaining ratio] [X]: addition amount of alkoxysilane condensate

The elongation percentage of the coating film laminated on the waterproof material is
50-250%, preferably 70-150%,
JISK 6301 “Vulcanized rubber physical test method” 3. Measured by the method specified in “Tensile test”. If the elongation is less than 50%, the coating film cannot follow the expansion and contraction of the waterproof material, and cracks occur. On the other hand, when the elongation is more than 250%, the surface of the coating film is contaminated with time and the degree of heat storage of sunlight increases, so that the deterioration of the waterproof material is accelerated.

In a waterproofing material containing a plasticizer in the composition, a plasticizer having a low molecular weight may migrate to the surface of the waterproofing layer with the passage of time, plasticizing the surface layer, and easily adhering dirt. In the present invention, when a coating composition containing a tetraalkoxysilane condensate is used, it is possible to prevent the transfer of the plasticizer due to the combined effect of the resin component that is the main component of the coating film and the tetraalkoxysilane condensate. It becomes possible. Further, a coating film formed from these compositions has a performance of excellent resistance to permeation of contaminants, and exhibits an effect of being easily washed away even when dirt is attached, in combination with surface hydrophilicity. The surface coating layer can be applied using a known spray, roller, brush, or the like, and is applied so that the dry film thickness is approximately 20 μm to 100 μm.

[0066]

The effects of the present invention will be clarified with reference to the following examples and comparative examples. (Test Method) Using the raw materials shown in Table 1, coating compositions having the respective formulations shown in Table 2 were produced. By applying this coating film composition to a 300 × 150 × 1 mm aluminum plate surface on which a 50 mm thick foamed polystyrene was laminated on the back surface in accordance with the combination shown in Table 3, the test sample back surface temperature in the initial state was measured. did. Next, an infrared lamp (1R11
0 V, 250 W) from a distance of 20 cm, and the back surface temperature of the test specimen when the temperature rise reached equilibrium was measured. In addition, as a coating method, a lower layer uses a trowel, and a coating amount is 2.5 kg.
/ M ² (1.8 mm dry film thickness), using a roller for the upper layer, and applying an amount of 0.30 kg / m ² (50 μm dry film thickness).
m). In addition, a primer was applied before forming the lower layer. As this primer, a moisture-curable urethane resin-based primer “Archiprimer N” manufactured by SK Kaken Co., Ltd. was applied at a coating amount of 0.20 kg / m ² .

Next, after the measurement of the backside temperature during infrared irradiation immediately after the preparation of the test piece, the test piece was subjected to outdoor exposure for 4 months at a 45 ° southward inclination in Ibaraki City, Osaka Prefecture. Was irradiated with infrared rays in the same manner as described above to measure the back surface temperature. Table 4 shows the results of the back surface temperature change immediately after the preparation of the test piece and after the exposure.

Each coating composition produced in the same manner was
On an aluminum plate of 50mm x 75mm x 0.8mm,
Sprayed so that the dry film thickness becomes 40 μm,
After drying and curing for 7 days under standard conditions, 3
After soaking for 18 hours and drying for 18 hours, the contact angle was measured with a CA-A type contact angle measuring device manufactured by Kyowa Interface Science Co., Ltd. Table 3 shows the contact angle values.

[0069]

[Table 1]

[0070]

[Table 2]

[0071]

[Table 3]

[0072]

[Table 4]

(Example 1) JIS A 6021 "waterproofing material for roof" The elongation of the coating film of formulation example 2 was 105 compared to the coating film of formulation example 1 corresponding to the urethane rubber-based coating film waterproofing material. % Elastic urethane-based coating film, and the coating film after 4 months exposure had no cracks and the surface contact angle was 30 ° because the elongation of the coating film was within the specified range. Within the specified range, there was little contamination due to hydrophilicity, and the thermal storage level showed an equilibrium temperature of 51 ° C at the initial stage of coating film formation, but showed almost the same performance as 53 ° C after 4 months exposure. It was found that the laminated coating film was less likely to cause deterioration of the waterproofing material due to heat as a result.

(Example 2) An acrylic silicon-based coating film of Formulation Example 3 having an elongation of 82% was laminated on the same waterproofing material coating film as in Example 1, and the elongation of the coating film was Due to the specified range, the coating film after 4 months exposure has not cracked, and the surface contact angle is 34 °, within the specified range. The initial equilibrium temperature was 56 ° C.
The performance was almost the same as that of ° C, the change was small, and as a result, it was found that the laminated coating film hardly caused deterioration of the waterproofing material due to heat.

(Example 3) A coating film formed by coating twice with a hydrated solidification type coating film waterproofing material “Aqueous Archroof” manufactured by SK Chemicals Co., Ltd. at a total application amount of 1.6 kg / m ² , This is a laminate of a weak solvent NAD type urethane resin-based coating film of Formulation Example 4 with a coating film elongation of 200% and the coating film elongation within a specified range. Has not occurred,
The contact angle of the surface was within the prescribed range of 40 °, which was less hydrophilic due to hydrophilicity, and the heat storage level was 50 ° C at the equilibrium temperature at the initial stage of coating film formation.
The performance was almost the same as that at 4 ° C., the change was small, and as a result, it was found that the laminated coating film hardly caused deterioration of the waterproofing material due to heat.

(Example 4) The same waterproof material coating film as in Example 1 was laminated with a fluorine resin-based coating film of Formulation Example 5 having a coating film elongation of 142%. Due to the specified range, the coating film after 4 months exposure has not cracked, and the surface contact angle is 32 ° within the specified range. The initial equilibrium temperature was 51 ° C.
The performance was almost the same as that of ° C, the change was small, and as a result, it was found that the laminated coating film hardly caused deterioration of the waterproofing material due to heat.

(Comparative Example 1) A urethane resin-based coating film of Formulation Example 6 with an elongation of 132% was laminated on the same waterproofing material coating film as in Example 1, and the elongation of the coating film was Due to the specified range, the coating film after exposure for 4 months did not have cracks.
However, since the contact angle of the coating film surface was out of the specified range of 74 °, a large amount of contaminants were attached, and the heat storage level was 56 ° C at the equilibrium temperature at the initial stage of film formation, but after 4 months exposure At 67 ° C., and as a result, it was found that the coating was a laminated coating film in which deterioration of the waterproof material was easily accelerated by heat.

(Comparative Example 2) The same waterproof material coating film as in Example 1 was laminated with a fluororesin-based coating film of Formulation Example 7 having an elongation of the coating film of 147%. Due to the specified range, the coating film after exposure for 4 months did not have cracks.
However, since the contact angle of the coating film surface was out of the specified range of 76 °, a large amount of contaminants were attached, and the heat storage level was 54 ° C at the equilibrium temperature at the initial stage of coating film formation, but after 4 months exposure At 67 ° C., and as a result, it was found that the coating was a laminated coating film in which deterioration of the waterproof material was easily accelerated by heat.

(Comparative Example 3) A urethane resin-based coating film of Formulation Example 8 having an elongation of 5% was laminated on the same waterproofing material coating film as in Example 1, and the elongation of the coating film was Since it was outside the specified range, the coating film after exposure for 4 months had cracked. Since the contact angle of the coating film surface was within the specified range of 30 °, adhesion of contaminants was small, but the coating film was broken, and the waterproof material was partially exposed, resulting in deterioration of the waterproof material. It was found that the film was a laminated coating film that easily caused cracks.

(Comparative Example 4) A urethane resin-based coating film of Formulation Example 9 having an elongation of 360% was laminated on the same waterproofing material coating film as in Example 1, and the elongation of the coating film was Since it was larger than the specified range, the coating film after 4 months of exposure did not crack. On the other hand, since the contact angle of the coating film surface is within the specified range of 50 °, the adhesion of contaminants was considered to be relatively small due to the hydrophilicity of the coating film surface, but due to the softness of the coating film, A lot of contaminants are attached, and the heat storage level is 65 ° C after exposure for 4 months, when the temperature at equilibrium in the initial stage of film formation is 51 ° C. As a result, the deterioration of the waterproofing material tends to accelerate due to heat. It turned out to be a coating film.

(Example 5) A 300 mm x 150 mm x 1 mm aluminum plate having a 50 mm-thick foamed polystyrene layered on the back surface was applied to the surface of a 300 mm x 150 mm aluminum plate. As a primer, a moisture-curable urethane resin-based primer made by SK Chemical Co., Ltd. painted the "archetype primer N" in the paint with the amount of 0.20kg / ^{m 2,}
Next, a hydrated solidification type coating film waterproofing material “aqueous arch roof” manufactured by SK Kaken Co., Ltd. was applied at a total application amount of 1.6 kg / m ² .
A coating film formed by re-coating and exposed for one year was used as a test sample, a waterproofing material coating film similar to that of Example 1 was laminated, and then the coating film of Formulation Example 2 had a 105% elongation of a fluororesin. Example 5 was obtained by laminating a system coating film. As a result, since the elongation of the coating film was within the specified range, the coating film after 4 months of exposure did not crack, and the surface contact angle was 30 °, which was within the specified range, and contamination due to hydrophilicity was observed. Although the heat storage level was 51 ° C. at the equilibrium temperature at the initial stage of coating film formation, the performance was almost the same as 53 ° C. even after exposure for 4 months, and there was little change. As a result, the waterproof material deteriorated due to heat. It was found that the coating film was not easily accelerated.

[0082]

According to the present invention, the surface of the elastic waterproof material, which is liable to lower the design of the external appearance due to contaminants, is beautifully maintained over a long period of time, and the waterproof performance of the waterproof material such as swelling or peeling due to heat is prevented as much as possible. However, it is possible to obtain a laminated waterproof coating film that does not crack on the surface layer by following the expansion and contraction of the waterproof material.

Claims (5)

[Claims] 1. A laminated waterproof structure wherein a coating film having a surface contact angle of 70 ° or less with water and an elongation percentage of 50 to 250% is laminated on the surface of a waterproof material. 2. A coating film having a surface contact angle of 70 ° or less with water and an elongation percentage of 50 to 250% comprises Si (OR ₁ ) (OR ₂ ) (OR ₃ ) (OR ₄ ) (R ₄ ) ₁ , R ₂ , R ₃ and R ₄ are formed from a coating composition containing a tetraalkoxysilane represented by the same or different alkyl group having 1 to 12 carbon atoms and / or a condensate thereof. The laminated waterproof structure according to claim 1, wherein: 3. A coating film having a surface contact angle of 70 ° or less with water and an elongation of 50 to 250% is a condensate of tetraalkoxysilane having an average degree of condensation of 4 to 20, and said condensate. The alkyl group in which the one having 1 to 2 carbon atoms and the one having 3 to 10 carbon atoms are mixed, and the mixing ratio is such that the alkyl group having 3 to 10 carbon atoms is 5 to 5 of all the alkyl groups in the condensate. The laminated waterproof structure according to claim 1, wherein the laminated waterproof structure is formed from a coating composition containing 50% of a compound. 4. A coating film having a surface contact angle with water of 70 ° or less and an elongation percentage of 50 to 250%, comprising (A) a weight average molecular weight of 5,000 to 80,000 and a hydroxyl value of 20 to 80%.
A coating composition comprising 150 KOH mg / g of a polyol, (B) a polyisocyanate compound, and (C) a tetraalkoxysilane condensate. An isocyanate compound is contained in an NCO / OH ratio of 0.6 to 1.4, and (C) a condensate of tetraalkoxysilane having an average degree of condensation of 4 to 20, wherein the alkyl group in the condensate is Compounds in which C1 to C2 and C3 to C10 are mixed, and the mixing ratio of the C3 to C10 alkyl groups is 5 to 50% of the total alkyl groups in the condensate Is formed from a coating composition characterized by containing 1.0 to 40.0 parts by weight in terms of SiO _2. 4. The laminated waterproof structure according to claim 1 or 3, wherein . 5. A coating film having a surface contact angle with water of 70 ° or less and an elongation percentage of 50 to 250%, comprising (A ′) having a solubility parameter of 6.5 to 9.5 and a weight average molecular weight. Is 5000 to 150,000, and the hydroxyl value is 15 to 100 KO.
Hmg / g, and the polyisocyanate compound (B ′) is NCO / O based on 100 parts by weight of the resin solid content of the polyol dissolved and / or dispersed in the non-aqueous solvent.
H ratio is 0.7 to 2.0, and the average degree of condensation of (C ′) tetraalkoxysilane is 4 to 20.
Wherein the alkyl group in the condensate has 1 to 1 carbon atoms.
3 and a compound having 4 to 12 carbon atoms are mixed, and the compound in which the mixing ratio of the alkyl group having 4 to 12 carbon atoms is 5 to 50% of the total alkyl groups in the condensate is SiO ₂
The laminated waterproof structure according to claim 1, which is formed from a coating composition characterized by containing 1.0 to 50.0 parts by weight in conversion.