JP3161587B2 - Non-staining paint composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-staining paint composition used for surface finishing of various materials such as metal, glass, porcelain tile, concrete, siding board, extruded board, and plastic.

[0002]

2. Description of the Related Art Conventionally, paint finishes have been performed to protect buildings such as buildings, civil engineering structures, etc., to provide designability, and to improve the appearance. In particular, in recent years, with the advent of highly durable paints such as a fluorine resin paint, an acrylic silicone resin paint, or an acrylic urethane resin paint, great progress has been made in the protection of the frame. However, these high-durability paints have resulted in the problem of contamination of the coating film surface being rather highlighted due to the excellent durability. In other words, the coating film formed by the paint before these high-durability paints was degraded by the ultraviolet rays of sunlight, and even if contaminants were attached, the coating was peeled off along with the deteriorated portion of the coating film surface. However, since the durability of the coating film was improved, the mechanism of deterioration and peeling of the coating film surface could not function. In recent years, especially in urban and suburban areas, where oily contaminants are floating in the air due to exhaust gas from automobiles, etc., these oily contaminants are coated with highly durable paint. If it adheres to the surface,
Significant soot-like or streak-like contamination (rain streak) occurred, and the paint finish applied to improve the cityscape sometimes did not make sense.

[0003] On the other hand, various non-staining paints have been published which make the surface of the coating film hydrophilic and remove the attached oily contaminants by the action of the rainwater during rainfall spreading on the coating film surface. I have. For example, Japanese Patent Application Laid-Open No. 4-37017
No. 6, in the coating by adding a segmented polymer containing a hydrophilic segment such as a polyalkylene oxide segment and a hydrophobic segment such as polysiloxane to the coating film surface, simultaneously imparting hydrophobicity and hydrophilicity, Some are expected to suppress the attachment of pollutants and to provide a cleaning effect by rainfall. The hydrophilicity of the coating film surface is represented, for example, by the contact angle of the coating film surface with water as shown in FIG. Due to the hydrophilicity of the surface of the coating film, water derived from precipitation or the like permeates and flows into the interface between the coating film and the contaminant, and an effect (soil release effect) of washing out the contaminant with the water is obtained.

The mechanism of making the surface of the coating film hydrophilic is described in the magazine “Surface” Vol. 32 No. 6 (199
4) On pages 55 to 61, "the surface properties of silicone-based polymer as a coating material" is introduced by the inventor of JP-A-4-370176 described above.
It is described as follows that the conversion of hydrophilicity / hydrophobicity of the coating film surface is caused by a morphological change. A silicone macromonomer having a structure in which an acylurethane bond serving as a hydrophilic segment and a siloxane bond serving as a hydrophobic segment are adjacent to each other is synthesized, and a copolymer thereof (containing 20% by weight of silicone macromonomer) on a film surface,
As a result of examining the relationship between the orientation state of each hydrophilic / hydrophobic segment and the atmosphere of the coating film surface, the initial contact angle with water on the copolymer film surface was 90 °,
After immersion in water at room temperature for 2 weeks, the surface becomes hydrophilic at 74 °, which is lower than that of a silicone-free system, and the contact angle with water recovers when left for one week, followed by drying for one week. Showed a tendency. In the acrylic copolymer film containing no silicone macromonomer as a comparative sample,
Such a phenomenon is not shown, and it can be assumed that the phenomenon is caused by the structure of the silicone macromonomer. The E of the surface after drying (DRY) and the surface immediately after immersing in water for 2 weeks (WET)
As a result of analyzing in the depth direction by SCA, element analysis was performed by selecting N as the element indicating the concentration on the surface of the hydrophilic segment and Si as the element indicating the concentration on the surface of the hydrophobic segment, and performing elemental analysis of both. Considering the state of the surface layer of the coating film by the concentration ratio, when the environment of the coating film surface is hydrophobic, the silicone segment is concentrated on the surface, and when the environment becomes hydrophilic, the acylurethane segment is concentrated. Was speculated.

[0005] This phenomenon is attributed to the localization of the hydrophobic segment having a low surface free energy on the surface of the coating film. That is, when water is present due to rainfall or the like, the morphology changes such that the water migrates to the coating film surface and is localized. However, as described in the above literature, the morphological change from hydrophobic to hydrophilic of the coating surface is not actually performed immediately, but rainfall on the coating surface is somewhat long, When the contact time with water is long, it can gradually shift to hydrophilicity.

Further, when there is no rainfall for a long period of time, that is, when sunny weather continues, the surface of the coating film goes back to hydrophobicity. It needs to be in contact with water again for a long time. One way to prevent this is to set the glass transition temperature of the polymer for forming the coating film low in order to easily cause morphological changes.However, as a result, the surface hardness is reduced, resulting in a soil release effect. This results in physical attachment of dust that cannot be washed away, which in turn leads to permanent contamination.

On the other hand, Japanese Patent Application No. 6-506632 (International Publication No. WO94 / 06870) discloses that a coating is mixed with an organosilicate, and the reaction between the two is to impart both hydrophilicity to the coating film surface and improvement in hardness. The intended method is shown. In general, organosilicates undergo a reaction as shown in [Chemical Formula 5], and silanol groups generated by such a reaction cause hydrophilicity of the coating film surface. Therefore, in order to make the surface of the coating film hydrophilic and improve the hardness, the hydrolysis reaction due to the presence of the first-stage acid catalyst is rate-determining. For this reason, in the paint, a surface treatment with an acid or the like is required in order to promote the reaction of the organosilicate. Considering the actual painting on the building outer wall, the reaction is thought to proceed due to acid rain, etc., but as described above, a considerable amount of time is required after the coating is formed in order to obtain the hydrophilic surface necessary for fully exhibiting the soil release effect. Requires a long time.

[0008]

Embedded image

Furthermore, Japanese Patent Application Laid-Open No. 145453/1994 discloses a method of obtaining a hydrophilic coating film by mixing an organosilicate with an acrylic silicone resin. Acrylic silicone resin has the same curing mechanism because the functional group contributing to its curing is a hydrolyzable silyl group similar to organosilicate, and therefore, usually an acid or base is cured for coating film formation. It is mixed as a catalyst. Since these catalysts cause the reaction of the organosilicate to proceed at the same time, the surface of the coating film is hydrophilized relatively quickly.
However, as described in Japanese Patent Application Laid-Open No. 6-145453, the acrylic silicone resin, which originally contains a hydrolyzable silyl group in a part of its molecule and adjusts the degree of crosslinking of the coating film, has many crosslinking sites. When a large amount of the organosilicate is blended, the crosslink density of the coating film becomes too large, the coating film becomes brittle, and ionic bonds are strong, and a large number of siloxane bonds which are highly hydrolyzable by acids or bases are introduced. The chemical resistance of the film is reduced, and as a result, the weather resistance of the coating film is reduced. Accordingly, in order to improve the hydrophilicity of the coating film, a large amount of the organosilicate is required, but there is a contradiction that if a large amount is added, the physical properties of the coating film are impaired.

[0010]

Among the coating films formed by the conventional non-staining type paints, those which require a long period of time to make the surface hydrophilic are those which have a low non-staining property in the early stage after the formation of the coating film. From the low level, rain streaks and the like are generated in a very short time after the completion of the painting work. Originally, the effect of not contaminating non-contamination type paint is to make the effect, and the user who uses it and the client who requests the painting work are expecting the effect. Therefore, even in the early stage after the formation of the coating film, the occurrence of stains, even if temporarily, betrays the expectations of these users and owners, and gives anxiety to the long-term non-staining effect. It will be. Furthermore, conventional non-contamination paints have the main purpose of flowing down contaminants due to rainfall, and have poor infiltration resistance of dirt once adhered.If there is no rainfall for a long period of time, oily dirt will be present in the coating film. It has been found that the water has penetrated, leaving dirt which is difficult to flow down due to rainfall.

Further, in order to impart non-staining properties to a commonly used urethane resin coating, in the case of a coating in which an organosilicate is mixed, the prepared coating is applied once on the base, especially in the field coating. Upon application, it was also found that the uneven surface of the underlayer affected the coating, and that uneven coating due to uneven suction occurred. Also, if the paint is applied again on the first coat in order to cover the uneven coating, an apparently beautiful coat can be formed, but the interlayer adhesion is significantly reduced, This coating film surface was blistered with time or cracked in the coating film, which revealed that the high durability performance characteristic of the original urethane resin paint was lacking. Therefore, when coating is performed a plurality of times, particularly in the case of repair or the like, since partial coating is performed again after a long period of time, such a decrease in interlayer adhesion is a serious problem.

In the case of a urethane resin paint mixed with an organosilicate, it takes a certain amount of time for the urethane resin to undergo a cross-linking and curing reaction, while the organosilicate is oriented on the surface of the coating film and reacted by moisture (moisture) in the air. Therefore, it is considered that a coating film having a very high crosslinking density on the surface is formed at the time when the curing of the urethane resin is completed. It is considered that such a coating film having a high cross-linking density on the surface has extremely poor adhesion to the second-layer coating film, resulting in a decrease in interlayer adhesion as described above.

Therefore, the problem to be solved by the present invention is:
Due to the action that occurs after the formation of the coating such as rainfall, the coating does not become hydrophilic for the first time, but the surface becomes hydrophilic immediately after the coating is formed, has a soil release effect to wash away contaminants, and Due to the cross-linked structure, it is strong but not brittle, has excellent resistance to penetration of oily stains, has good weather resistance and other physical properties of the coating film, and has good interlayer adhesion when performing multiple coatings (hereinafter referred to as “recoating”). The present invention provides a non-stained coating composition which provides a non-stained coating film which is excellent in the properties and which can effectively prevent the generation of blisters, cracks or lifting over time.

[0014]

Means for Solving the Problems In order to solve such problems, the present inventors have made intensive studies and as a result, the surface becomes hydrophilic immediately after the formation of the coating film, and the resistance to the penetration of contaminants is also reduced. An excellent coating composition has been invented. That is, the present invention relates to the following non-staining paint composition.

1. (A) 5000-8 in weight average molecular weight
0000, hydroxyl value of 20 KOHmg / g to 150 KOHmg / g
g of tertiary amino group-containing acrylic polyol
(B) 2 to 40 parts by weight per 100 parts by weight
Of an alkoxysilane compound having an alkylene oxide chain and having a weight average molecular weight of 150 to 3500 is 0.1 to 20 parts by weight in terms of solid content, (C)

Embedded image (D) polyisocyanate in an OH / NCO ratio of 0.6 to 40 parts by weight based on the hydroxyl groups of the acrylic polyol (A). A non-staining paint composition, which is contained so as to be 1.5 or less. 2. (A) a weight average molecular weight of 5000 to 80000,
A main ingredient containing a tertiary amino group-containing acrylic polyol having a hydroxyl value of 20 KOHmg / g to 150 KOHmg / g;
(B) an alkoxysilane compound having a weight average molecular weight of 150 to 3500 containing an alkylene oxide chain having 2 to 40 repeating units, and (C) a general formula

Embedded image And (D) two packs of a curing agent containing a polyisocyanate, and the solid content in terms of solid content is calculated based on 100 parts by weight of the solid content at the time of use (A). B) is 0.1 to 20 parts by weight,
(C) is 1 to 40 parts by weight, and (D) is (A)
OH / NCO ratio of 0.6 to 1.5
A non-staining paint composition characterized by mixing and mixing. 3. (A) a weight average molecular weight of 5000 to 80000,
A tertiary amino group-containing acrylic polyol having a hydroxyl value of 20 KOHmg / g to 150 KOHmg / g, and (B) an alkoxysilane compound having a weight average molecular weight of 150 to 3500 containing an alkylene oxide chain having 2 to 40 repeating units. (C) general formula

Embedded image And (D) two packs of a curing agent containing a polyisocyanate, and the solid content in terms of solid content is calculated based on 100 parts by weight of the solid content at the time of use (A). B) is 0.1 to 20 parts by weight,
(C) is 1 to 40 parts by weight, and (D) is (A)
OH / NCO ratio of 0.6 to 1.5
A non-staining paint composition characterized by mixing and mixing. 4. (A) a weight average molecular weight of 5000 to 80000,
A tertiary amino group-containing acrylic polyol having a hydroxyl value of 20 KOHmg / g to 150 KOHmg / g, (B) an alkoxysilane compound having an alkylene oxide chain having 2 to 40 repeating units and a weight average molecular weight of 150 to 3500,
(C) General formula

Embedded image And (D) a two-pack of a curing agent containing a polyisocyanate, and based on 100 parts by weight of a solid content at the time of use (A), (B) 0.1 to 20 parts by weight in terms of solid content, (C)
And 1 to 40 parts by weight, and (D) is mixed with the hydroxyl group of (A) so that the ratio of OH / NCO becomes 0.6 to 1.5. Paint composition. 5. (B) A compound in which the alkylene oxide chain of the alkoxysilane compound is an ethylene oxide chain and one terminal is a hydroxyl group. From 4. A non-staining paint composition according to any one of the above. 6. As the alkyl silicate (C), at least one of tetramethyl silicate and tetraethyl silicate is used. From 4. A non-staining paint composition according to any one of the above. 7. 1. The polyisocyanate is dissolved in a solvent containing 5% by weight or more of ketone. Or 3.
A non-staining paint composition according to claim 1. 8. Further, (E) a coloring pigment is contained. A non-staining paint composition as described in the above. 9. 1. The base material further comprises (E) a color pigment. From 4. A non-staining paint composition according to any one of the above. 10. Further, (F) an extender pigment is contained. A matte, non-staining paint composition as described. 11. 1. The base material further comprises (F) extender pigment. From 4. A matte non-staining paint composition according to any one of the above.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail along with its embodiments. The polyol (A) refers to an acrylic polyol generally used in the polyurethane technical field, which contains a tertiary amino group, and is non-staining by mixing and reacting with a polyisocyanate as a curing agent. In the non-staining coating film formed from the coating composition, it is a main component of the coating film formation.

Such acrylic polyols include:
A hydroxyl group-containing acrylate or methacrylate represented by the general formula as shown in Chemical formula 10, and a polymerizable unsaturated bond-containing tertiary amine compound represented by the general formula such as Chemical formula 11, It is a copolymer with a polymerizable monomer.

Embedded image

Embedded image

Examples of such hydroxyl-containing acrylates or methacrylates include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 2-hydroxyethyl methacrylate, Hydroxyalkyl esters of acrylic acid or methacrylic acid such as 2-hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2-hydroxypentyl methacrylate, and further glycerin;
Monoethylenically unsaturated monomers having a hydroxyl group such as monoester of acrylic acid or methacrylic acid of polyhydric alcohol such as trimethylolpropane, N-methylolacrylamide or N-methylolmethacrylamide, 2-hydroxy-3-chloropropyl acrylate And chlorine-containing compounds such as 2-hydroxy-3-chloropropyl methacrylate. Particularly preferred among these are:
2-hydroxyethyl methacrylate, acrylic acid-2-
Hydroxyethyl, 2-hydroxypropyl methacrylate and the like.

On the other hand, as an example of a tertiary amine compound containing a polymerizable unsaturated bond, 2- (N, N-dimethylamino)
Ethyl methacrylate, 2- (N, N-dimethylamino) ethyl acrylate and the like can be mentioned. Particularly preferred among these is 2- (N, N-dimethylamino) ethyl methacrylate.

Next, other monomers copolymerizable with the above-mentioned hydroxy-containing acrylates and methacrylates include, for example, the following. Acrylic acid, or an acrylate such as methyl, ethyl, propyl, butyl, or 2-ethylhexyl acrylate, methacrylic acid, or methyl, ethyl, propyl, butyl, or 2-ethylhexyl methacrylate;
Methacrylic esters such as lauryl, styrene, or styrene derivatives such as α-methylstyrene and β-chlorostyrene, vinyl acetate, vinyl propionate, vinyl esters such as vinyl isopropionate, acrylonitrile,
Nitriles such as methacrylonitrile, among which particularly preferred are methyl acrylate, ethyl acrylate,
Butyl acrylate, methyl methacrylate, butyl methacrylate, lauryl methacrylate, acrylic acid, methacrylic acid, styrene, acrylamide, vinyl acetate and the like.

The molecular weight of the polyol used in the present invention is from 5,000 to 80,000, preferably from 20,000 to 60,000 in terms of weight average molecular weight. Molecular weight 5000
When it is smaller, the curability and durability of the coating film are not sufficient, and when it is more than 80000, the finish property of the coating film is not sufficient.

Further, the hydroxyl value of these polyols is 2
0 KOHmg / g to 150 KOHmg / g, preferably 30 KOH
mg / g to 100 KOHmg / g. Hydroxyl value is 20 KOH
If the amount is less than mg / g, the durability and stain resistance of the coating film are poor.
If it exceeds 50 KOHmg / g, the durability and flexibility of the coating film are not sufficient.

The glass transition point of these polyols is from -10 ° C to 150 ° C, preferably from 10 ° C to 100 ° C. When the temperature is lower than -10 ° C, the soil removal property and the soil recovery property are poor. When the temperature is higher than 150 ° C, flexibility and durability are poor.

The alkoxysilane compound (B) containing an alkylene oxide chain (hereinafter referred to as "component (B)") used in the present invention comprises a repeating unit of an alkylene oxide group and at least one alkoxysilyl group. Is a compound having In the alkylene oxide group repeating unit of the component (B), the alkylene portion has 2 to 4 carbon atoms, and the repeating number is 2 to 40, preferably 2 to 20.

The component (B) may have an alkoxysilyl group at both ends, an alkoxysilyl group at one end, and another functional group at the other end. Examples of such a functional group that can be provided at one end include a vinyl group, a hydroxyl group, an epoxy group, an amino group, an isocyanate group, and a mercapto group.
The functional group may be bonded to an alkoxysilyl group via a urethane bond, a urea bond, a siloxane bond, an amide bond, or the like. Such (B)
As the component, for example, a compound synthesized by reacting a compound containing a polyalkylene oxide chain with a compound containing an alkoxysilyl group (hereinafter, referred to as a coupling agent) can be used.

The polyalkylene oxide chain-containing compound preferably has a weight average molecular weight of 150 to 3500,
200 to 1500 are more preferred. When the weight-average molecular weight is less than 150, the cured film finally obtained is inferior in hydrophilicity, and a cleaning effect of contaminants due to rainfall cannot be obtained. When the weight-average molecular weight exceeds 3500, the water resistance of the cured product and Hardness decreases. Examples of such a polyalkylene oxide chain-containing compound include polyethylene glycol, polyethylene-propylene glycol, polyethylene-tetramethylene glycol, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polyoxyethylene diglycolic acid, polyethylene glycol vinyl ether, and polyethylene. Examples thereof include glycol divinyl ether, polyethylene glycol allyl ether, and polyethylene glycol diallyl ether. The polyalkylene oxide chain-containing compound can be selected from one kind or a combination of two or more kinds.

On the other hand, the coupling agent is, for example, a compound having at least one or more alkoxysilyl groups and other substituents in one molecule. Specific examples of the coupling agent include β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, N-β (Aminoethyl) γ-aminopropylmethyldimethoxysilane, N-
β (aminoethyl) γ-aminopropylmethyltrimethoxysilane, γ-aminopropyltrimethoxysilane,
Examples include γ-aminopropyltriethoxysilane, isocyanate-functional silane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, and γ-methacryloxypropyltriethoxysilane.

The synthesis of the component (B) is not particularly limited, but a compound containing a polyalkylene oxide chain and a coupling agent are separately prepared. For example, for each compound having a polymerizable double bond, a radical polymerization initiator is used. In addition to copolymerization using an amino group, it can be synthesized by a known method such as an addition reaction of an amino group / epoxy group, an isocyanate group / hydroxyl group or an isocyanate group / amino group. It can also be synthesized by a method in which ethylene oxide is ring-opened to an alkoxysilyl compound having an active hydrogen group such as a primary or secondary amino group.

When the copolymerization is carried out using a radical polymerization initiator, at least one or more of the polyalkylene oxide chain-containing compounds having a polymerizable double bond and at least one or more of the coupling agents may be used in a non-reactive, appropriate manner. In a suitable solvent. At this time, as a radical polymerization initiator to be used, for example, benzoyl peroxide, dichlorobenzoyl peroxide, 2,5-di (peroxybenzoate) hexyne-3,1,3-bis (t-butylperoxy) Isopropyl) benzene, t
Perester compounds such as -butyl perbenzoate,
Examples include azo compounds such as azobisisobutyronitrile and dimethylazobutyrate, and organic peroxides.

As the polyalkylene oxide chain-containing compound having a polymerizable double bond, for example, polyethylene glycol vinyl ether can be used, and γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyl can be used as a coupling agent. Methyldiethoxysilane and γ-methacryloxypropyltriethoxysilane can be used alone or in combination of two or more.

When the compound is synthesized by an addition reaction of isocyanate / polyol, for example, a compound having a hydroxyl group at a terminal such as polyethylene glycol is used as a compound containing a polyalkylene oxide chain, and an isocyanate such as an isocyanate-containing coupling agent is used as a coupling agent. Compounds having a group are mixed and synthesized. In this synthesis method, it is also possible to use a reaction catalyst such as dibutyltin laurate, dibutyltin malate or dioctyltin malate.

As the component (B) synthesized in these reactions, a compound obtained by adding a coupling agent to both ends or one end of a polyalkylene oxide chain-containing compound is obtained, and a single compound or a mixture of both compounds can be used. Is done.

Among these components (B), those having an alkylene oxide chain of an ethylene oxide chain and a hydroxyl group at one end are the most preferred because of the high non-staining effect of the present invention, that is, high stain resistance and permeation resistance. preferable.

The proportion of the component (B) is from 0.1 to 20 parts by weight, preferably from 0.2 to 10 parts by weight, based on 100 parts by weight of the resin solids of the component (A). If the amount is less than 0.1 part by weight, the obtained cured product is not sufficiently hydrophilic and 2
If the amount exceeds 0 parts by weight, the compatibility with the resin, the water resistance of the cured product, and the like will be poor.

Next, (C) a general formula used in the present invention

Embedded image The alkyl silicate represented by and / or a condensate thereof (hereinafter, referred to as a component (C)) is, for example, tetramethyl silicate, tetraethyl silicate, tetra-
One or more selected from n-propyl silicate and tetra-i-propyl silicate, as the condensate, one or more selected from those obtained by condensing the above tetraalkyl silicate under hydrolysis conditions can give. In particular, use of at least one of tetramethyl silicate and tetraethyl silicate or a condensate thereof is preferred from the viewpoint of the balance between flexibility and denseness of the formed coating film. The degree of condensation of the condensate is preferably from 2 to 20, and when the degree of condensation exceeds 20, the viscosity of the condensate increases, handling becomes inconvenient, and the compatibility with the polyol deteriorates, resulting in cloudiness in the paint. Become.

The mixing ratio of the component (C) is from 1 to 40 parts by weight based on 100 parts by weight of the resin solids of the component (A).
Suitably, parts by weight, preferably 2 to 20 parts by weight, are suitable. If the amount is less than 1 part by weight, the surface hardness of the cured coating film is not sufficient, causing physical adhesion of contaminants, causing permanent contamination. If the amount exceeds 40 parts by weight, compatibility with the resin, cured product This is because there is a problem that the appearance deteriorates and cracks occur.

[0037]

[0038]

In the present invention, (D) a polyisocyanate (hereinafter referred to as the (D) component) is blended and crosslinked and cured to form a non-contaminated coating film. Examples of such a curing agent include toluene diisocyanate (TDI), 4,4-diphenylmethane diisocyanate (pure-MDI), polymeric MDI, xylylene diisocyanate (XDI),
Isocyanate monomers such as hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), hydrogenated XDI, and hydrogenated MDI are converted into allophanate, biuret, dimerization (uretidion), trimerization (isocyanurate), adduct, carbodiimide reaction, and the like. Derivatized forms and mixtures thereof can be used. These components (D) are preferably used as a solution in a solvent containing no active hydrogen. In consideration of the problem of yellowing of the formed coating film, it is preferable to use an aliphatic or alicyclic polyisocyanate, or a polyisocyanate in which both are mixed. Further, these components (D) include alcohols, phenols, ε
-It can also be used in the form of a blocked isocyanate using a blocking agent such as caprolactam, oximes and active methylene compounds. These components (D) are also preferably used as a solution in a solvent containing no active hydrogen.

The components (D) and (A) are mixed in an OH / NCO ratio of 0.6 to 1.5, preferably 0.1 to 0.5.
It is performed at a ratio such that it becomes 8 to 1.2. At this time, OH / N
When the CO ratio is less than 0.6, the curability, stain recovery property and durability of the coating film are poor, and when it is more than 1.5, the durability, curability and stain removal properties are poor.

These components (A), (B), (C) and (D) can form a non-contaminated coating film by mixing the components at the time of use. A),
A mixture of components (B) and (C), and a mixture of component (D) 2
Stored in a pack, a mixture of components (A) and (B), and stored in two packs of components (C) and (D).
Component (C), stored in two packs of components (B) and (D), and further mixed component (B), (C) and (D) and stored in two packs of component (A) However, when used, they may be mixed in such a ratio that the optimum OH / NCO ratio is obtained. Particularly, two packs of a mixture of the components (B), (C) and (D) and the component (A) are desirable from the viewpoint of storage stability of the components (B) and (C). In this case, acetone, methyl ethyl ketone, 2-
Those using 5% by weight or more of a ketone such as pentanone, 2-hexanone, cyclohexanone, etc., alone or in a mixture, are excellent in storage stability. In particular, in order to prevent the isocyanate group from reacting and becoming inactive due to water entering the storage container,
It is desirable to add TI (manufactured by Bayer).

Further, when the above-mentioned blocked isocyanate is used, (A), (B), (C) and (D) can be made into one pack, and this one-pack type paint is used. In this case, NCO can be generated by dissociating the blocking agent by heating or the like after coating to crosslink and cure the coating film. In this case, it is preferable to add a catalyst which is usually used for promoting the reaction between the isocyanate group and the hydroxyl group.

In the composition of the present invention, (A), (B),
In addition to the transparent (clear) coating of the components (C) and (D), a coloring pigment may be blended to form a coloring (enamel) coating. Examples of such coloring pigments include titanium oxide, zinc oxide, Carbon black, ferric oxide,
Inorganic pigments such as lead chromate (molybdate orange), yellow iron oxide, ocher, ultramarine, cobalt green, etc., azo, naphthol, pyrazolone, anthraquinone, perylene, quinacridone, disazo, and isoindo Organic pigments such as linone, benzimidazole, phthalocyanine and quinophthalone can be used.

It is also possible to use extenders such as heavy calcium carbonate, clay, kaolin, talc, precipitated barium sulfate, barium carbonate, white carbon, and diatomaceous earth. In particular, when a matte coating film is formed, it is optimal to use white carbon or diatomaceous earth which least impairs the non-staining effect on the coating film surface.
When these inorganic substances are added to the paint, it is preferable to treat the powder surface with a coupling agent or to add the coupling agent to the paint.

In the composition of the present invention, it is possible to add various additives which can be usually added to a paint to such an extent that the effects of the present invention are not affected. Examples of such additives include plasticizers, preservatives, fungicides, anti-algal agents, defoamers, leveling agents, pigment dispersants, anti-settling agents, anti-sag agents, matting agents, ultraviolet absorbers and the like. can give.

In the coating composition of the present invention, each component can be mixed by a general stirring device such as a propeller type, and the obtained composition can be used for coating generally used in coating. It can be applied by a method, for example, spray coating, brush coating and the like. Further, a device that simultaneously performs mixing and coating, such as a multi-head type spray device, may be used.

EXAMPLES Examples and comparative examples are shown below to further clarify the features of the present invention.

Synthesis Example 1 Synthesis Example of Tertiary Amino Group-Containing Acrylic Polyol 1 A reactor equipped with a heating device, a stirrer, a reflux device, a dehydrator, and a thermometer was sealed with nitrogen, and then 80 parts by weight of xylene, butyl acetate. Charge 20 parts by weight and raise the temperature to 80-85 ° C.
Subsequently, 26 parts by weight of styrene and 26 parts of methyl methacrylate
Parts by weight, 12 parts by weight of n-butyl acrylate, 25 parts by weight of n-butyl methacrylate, 10 parts by weight of 2-hydroxyethyl methacrylate, and 1 part by weight of 2- (N, N-dimethylamino) ethyl methacrylate A mixture obtained by adding 1.5 parts by weight of azobisisobutyronitrile to the resulting monomer mixture was continuously dropped into the reaction vessel over 3 hours, and after completion of the dropping, the mixture was heated and stirred for 2 hours. Thereafter, 0.5 parts by weight of azobisisobutyronitrile was added a total of 4 times every 2 hours, and the mixture was heated and stirred for 3 hours to complete the polymerization reaction. The resin solution thus prepared was colorless and transparent, had a Gardner bubble viscosity (25 ° C.) of X to Y, and had a nonvolatile content of 50%. The weight average molecular weight is 30,000, the hydroxyl value is 20 KOHmg / g (value in varnish conversion, 4 in solids conversion)
0 KOHmg / g) and the glass transition temperature was about 50 ° C.

(Synthesis Example 2) Acrylic polyol containing no tertiary amino group 2 Synthesis Example After sealing with nitrogen in a reaction vessel equipped with a heating device, stirrer, reflux device, dehydrator, and thermometer, 80 parts by weight of xylene, acetic acid Charge 20 parts by weight of butyl and raise the temperature to 90 to 95 ° C.
Subsequently, styrene 27 parts by weight, methyl methacrylate 26
1.5 parts by weight of azobisisobutyronitrile in a monomer mixture consisting of 12 parts by weight of n-butyl acrylate, 25 parts by weight of n-butyl methacrylate, and 10 parts by weight of 2-hydroxyethyl methacrylate Was added dropwise to the reaction vessel over 3 hours, and after completion of the dropwise addition, the mixture was heated and stirred for 2 hours. Thereafter, 0.5 parts by weight of azobisisobutyronitrile was added a total of 4 times every 2 hours, and the mixture was heated and stirred for 3 hours to complete the polymerization reaction. The resin solution thus prepared was colorless and transparent, had a Gardner bubble viscosity (25 ° C.) of X to Y, and had a nonvolatile content of 50%. Weight average molecular weight: 30,000, hydroxyl value: 20 K
OHmg / g (Value in varnish conversion, 40 KOHmg in solid content conversion)
/ G) and the glass transition temperature was about 50 ° C.

(Synthesis Example 3) Polyalkylene oxide chain-containing coupling agent 1 Synthesis Example Polyethylene glycol 200 (average molecular weight 200; Wako Pure Chemical Industries, Ltd.) was placed in a reaction vessel equipped with a heating device, a stirrer, a reflux device, a dehydration device, and a thermometer. 20 parts by weight of Yakuhin Co., Ltd., 54.3 parts by weight of Y-9030 (manufactured by Nippon Unicar Co., Ltd.), which is an isocyanate-containing silane, and 0.05 part by weight of dibutyltin dilaurate were charged. The reaction was carried out at 8 ° C. for 8 hours to obtain a light yellow polyethylene oxide chain-containing coupling agent (1). The weight average molecular weight of this polyethylene oxide chain-containing coupling agent was 800 as measured by gel permeation chromatography (hereinafter referred to as GPC) in terms of polystyrene.

(Synthesis Example 4) Synthesis Example of Coupling Agent 2 Containing Polyalkylene Oxide Chain Epolite 40E which is polyethylene glycol glycidyl ether (average) was placed in a reaction vessel equipped with a heating device, a stirrer, a reflux device, a dehydration device, and a thermometer. Molecular weight 170: 100 parts by weight (manufactured by Kyoeisha Chemical Co., Ltd.) and A-1100 (manufactured by Nippon Unicar Co., Ltd.) which is an amino group-containing silane.
0 parts by weight and reacted at 50 ° C. for 8 hours to obtain a pale yellow polyethylene oxide chain-containing coupling agent (2). The weight average molecular weight of the polyethylene oxide chain-containing coupling agent was 980 as measured by GPC in terms of polystyrene.

Example 1 Aluminum plate 1 of 150 mm × 70 mm × 0.8 mm
On two sheets, SK # 1000 primer (epoxy resin primer, manufactured by SK Chemical Co., Ltd.) is spray-coated so that a dry film thickness is about 30 μm, and dried at a temperature of 20 ° C. and a humidity of 65% for 8 hours. Was. Next, using the raw materials shown in Table 1, based on 100 parts by weight of the solid content of the tertiary amino group-containing acrylic polyol 1 as shown in Table 3,
84 parts by weight of titanium oxide were uniformly kneaded, and 1.0 part by weight of a coupling agent 1 containing a polyethylene oxide chain and 20 parts by weight of methyl silicate 1 were blended into the mixture to prepare a main agent of a white paint. A non-staining paint composition containing 15.0 parts by weight of a hexamethylene diisocyanate trimer as a curing agent so that the OH / NCO ratio becomes 0.9 with respect to the base material was used as the SK # 1000 primer for the aluminum plate. The surface was spray-coated so that the dry film thickness was 25 μm.

<Preparation of Specimen> Seven of the aluminum plates thus coated were cured for 3 days at a temperature of 20 ° C. and a humidity of 65% for the following tests (1) to (7). ,
Further, the non-staining paint composition produced at the same compounding ratio was spray-coated again so that the dry film thickness became 25 μm. At this time, the dry film thickness of the entire non-contaminated coating film was 50 μm.
m. <Test method> (1) Evaluation of appearance after curing of coating film The test specimen was cured at a temperature of 20 ° C and a humidity of 65% for 7 days, and then subjected to JIS.
K5400 (1990) 7.1 The appearance of the coating film was evaluated according to the appearance test of the coating film.

(2) Durability evaluation The test specimens were cured at a temperature of 20 ° C. and a humidity of 65% for 7 days,
K5400 (1990) 8.20 Following boiling water test, immerse in boiling water for 1 hour, shake off water, temperature 20 ° C, humidity 65%
The coating film after drying for 2 hours was evaluated for appearance.

(3) Evaluation of acid resistance The test specimen was cured at a temperature of 20 ° C. and a humidity of 65% for 7 days,
K5400 According to the 8.22 acid resistance test, after immersion treatment in a 5% by weight sulfuric acid aqueous solution at 20 ° C for 1 week, the coating surface was washed with water and
The coating film after drying for 2 hours was evaluated for appearance.

(4) Evaluation of Alkali Resistance The test specimen was cured at a temperature of 20 ° C. and a humidity of 65% for 7 days.
K5400 5 wt% at 20 ℃ according to 8.21 alkali resistance test
After being immersed in an aqueous sodium hydroxide solution for one week, the coating film surface was washed with water and dried at 20 ° C. for 2 hours, and the appearance of the coating film was evaluated.

(5) Measurement of contact angle with water After the preparation of the test piece, the contact angle was measured at a temperature of 20 ° C. and a humidity of 65% for 24 hours.
After drying for 2 hours and 14 days, 0.2
Immediately after dropping cc of deionized water and dropping at 20 ° C, the contact angle one minute later was measured with a CA-A type contact angle measuring device manufactured by Kyowa Interface Science Co., Ltd.

(6) Stain resistance After the test specimen was cured at a temperature of 20 ° C. and a humidity of 65% for 7 days,
Outdoor exposure was conducted in Ibaraki City, Osaka Prefecture at a 45 ° southward inclination, and the lightness difference (△ L value) between the initial and six months was measured using a TC-1800 type color difference meter manufactured by Tokyo Denshoku Co., Ltd. Colored.

(7) Resistance to stain penetration The test specimen was cured at a temperature of 20 ° C. and a humidity of 65% for 7 days.
K5400 8.10 15% by weight on coating surface according to stain resistance test
Aqueous dispersion liquid of carbon black of 20m in diameter
m, and dropped at a height of 5 mm, and left in a constant temperature room at 50 ° C. for 2 hours. Thereafter, the film was washed in running water, and the degree of contamination on the coating film surface was visually evaluated. <Preparation of Interlayer Adhesion Evaluation Specimen> The remaining five aluminum plates coated as described above were subjected to a temperature of 20 ° C. and a humidity of 6
After drying at 5% for 16 hours, 1, 3, 5 or 7 days,
Using the non-staining paint composition prepared at the same compounding ratio, the composition was spray-coated again so that the dry film thickness became 25 μ, to obtain a test piece for evaluating interlayer adhesion. At this time, the dry film thickness of the entire non-contaminated coating film is 50 μm.

(8) Evaluation of interlayer adhesion The prepared specimen was cured for 7 days at a temperature of 20 ° C and a humidity of 65% for 7 days, and adhered according to JIS K5400 (1990) 8.5 Adhesion Test 8.5.1 Cross-cut method. The sex was evaluated. The evaluation was shown by the scores as shown in Table 2.

<Evaluation Results> In the evaluation of the appearance of the coating film after curing, the durability, the acid resistance and the alkali resistance evaluation, no abnormality was observed in the coating film, and the coating film was in a good state. The contact angle for water is 2
4 hours after measurement, 62 ° immediately after dropping, 56 ° after 1 minute,
72 hours after measurement, 56 ゜ immediately after dropping, 48 minutes after 1 minute
゜, 14 days after measurement, 56 immediately after dripping, 48 minutes after 1 minute
The contact angle was lower at the initial time points such as 24 hours and 72 hours than in the comparative examples. In the stain resistance evaluation, the ΔL value was −2.0, and good stain resistance was obtained. Further, no trace was observed in the stain penetration resistance test. Therefore, it was proved that the adhered stain was present only on the surface of the coating film and was an excellent non-staining paint which could completely flow down by rainfall. Furthermore, it shows that good interlayer adhesiveness is exhibited and that recoatability is excellent. In particular, after a long period of time after the formation of the first coating film, even when the second layer is applied by lamination, the adhesion between layers is excellent, so that it is proved that the non-contamination coating material has excellent recoating properties. Was.

(Examples 2 to 6) A mixture was prepared according to Example 1 with the composition shown in Table 3, and the same evaluation as in Example 1 was performed. Also, the contact angle was lower at the initial time such as 24 hours and 72 hours than in the comparative example. In addition, good results were also obtained in the evaluation of stain resistance and stain penetration, and no peeling occurred in interlayer adhesion.

Comparative Example 1 Evaluation was performed in the same manner as in Example 2 except that 5 parts by weight of polyethylene glycol 1 was used instead of the coupling agent 1 containing a polyethylene oxide chain as in the formulation shown in Table 4. As a result, the results were as shown in Table 6, and gloss was observed in the appearance of the coated film after curing, the durability of the coating film, and the acid resistance and alkali resistance tests. Furthermore, the decrease in the contact angle in the initial stage was not as large as that of the example, and good results were not obtained in the evaluation of stain resistance and stain penetration. There was no particular problem with the interlayer adhesion.

(Comparative Example 2) Evaluation was performed in the same manner as in Example 1 except that the polyethylene oxide chain-containing coupling agent 1 and the alkyl silicate were not used as in the composition shown in Table 4, and the results were as shown in Table 6. There was no problem in the appearance of the coating film after curing, the durability of the coating film, the acid resistance, and the alkali resistance test. Also, good results were not obtained in the evaluation of stain penetration. There was no particular problem with the interlayer adhesion.

(Comparative Example 3) As shown in Table 4, instead of the amino group-containing acrylic polyol 1, an amino group-free acrylic polyol 2 was used, and instead of the polyethylene oxide chain-containing coupling agent 2, Evaluation was performed in the same manner as in Example 3 except that 10 parts by weight of polyethylene glycol 2 was used. The results are as shown in Table 6, and the appearance of the cured coating film, durability of the coating film, acid resistance, and Delustering occurred in the alkaline test. Furthermore, the decrease in the contact angle in the initial stage was not as large as that of the example, and good results were not obtained in the evaluation of stain resistance and stain penetration. Also, regarding the interlayer adhesion, when recoating after one day,
Large delamination occurred.

Comparative Example 4 As shown in Table 4, instead of the amino group-containing acrylic polyol 1, an amino group-free acrylic polyol 2 was used, and the polyethylene oxide chain-containing coupling agent 2 was not used. Except for the above, evaluation was performed in the same manner as in Example 3. The results were as shown in Table 6, and no particular problem occurred in the durability, acid resistance, and alkali resistance tests of the coating film. Was not as good as the Examples, and good results were not obtained in the evaluation of stain resistance and stain penetration. Further, with respect to the interlayer adhesion, when recoating was performed after one day had passed, large delamination occurred.

[0066]

According to the non-staining paint composition of the present invention, the coating film is not made hydrophilic for the first time due to the action that occurs after the coating film formation such as rainfall, but the surface becomes hydrophilic immediately after the coating film formation. And because of high resistance to dirt penetration,
Pollutants are washed away together with rainwater by rainfall, and the urethane-based coating film having excellent weather resistance has an effect of keeping the surface of the object to be coated beautiful without being stained.

[Table 1]

[Table 2]

[Table 3]

[Table 4]

[Table 5]

[Table 6]

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a contact angle of a coating film to water.

[Description of Signs] a Water Drop b Coating Film θ Contact Angle

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hisashi Suzuki 1-25-10 Shimizu, Ibaraki-shi, Osaka SK Kaken Co., Ltd. Examiner Kenji Hara (56) References JP-A-8-60092 (JP) JP-A-6-287511 (JP, A) JP-A-63-230721 (JP, A) JP-A-9-137119 (JP, A) JP-A-7-238260 (JP, A) 7-278467 (JP, A) JP-A-9-31401 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09D 175/04 C09D 183/02 C09D 183/04

Claims (11)

(57) [Claims] (A) a weight average molecular weight of 5,000 to 800
00, hydroxyl value of 20 KOHmg / g to 150 KOHmg / g
Solid content of tertiary amino group-containing acrylic polyol 10
With respect to 0 parts by weight, (B) the repeating unit is 2 to 40,
Weight average molecular weight 1 containing alkylene oxide chain
50 to 3500 alkoxysilane compounds having a solid content of 0.1 to 20 parts by weight, (C) a compound represented by the general formula: (D) polyisocyanate in an OH / NCO ratio of 0.6 to 40 parts by weight based on the hydroxyl groups of the acrylic polyol (A). A non-staining paint composition, which is contained so as to be 1.5 or less. (A) a weight average molecular weight of 5,000 to 80
000, hydroxyl value is from 20 KOHmg / g to 150 KOHmg / g
A main agent containing a tertiary amino group-containing acrylic polyol, (B) an alkoxysilane compound having an alkylene oxide chain having 2 to 40 repeating units and a weight average molecular weight of 150 to 3500, (C) a general formula: ] And (D) two packs of a curing agent containing a polyisocyanate, and the solid content in terms of solid content is calculated based on 100 parts by weight of the solid content at the time of use (A). B) is 0.1 to 20 parts by weight,
(C) is 1 to 40 parts by weight, and (D) is (A)
OH / NCO ratio of 0.6 to 1.5
A non-staining paint composition characterized by mixing and mixing. 3. The weight average molecular weight of (A) 5,000 to 80.
000, hydroxyl value is from 20 KOHmg / g to 150 KOHmg / g
A tertiary amino group-containing acrylic polyol, (B) a main agent containing an alkoxysilane compound having a weight average molecular weight of 150 to 3500 containing an alkylene oxide chain having 2 to 40 repeating units, and (C) a general formula: ] And (D) two packs of a curing agent containing a polyisocyanate, and the solid content in terms of solid content is calculated based on 100 parts by weight of the solid content at the time of use (A). B) is 0.1 to 20 parts by weight,
(C) is 1 to 40 parts by weight, and (D) is (A)
OH / NCO ratio of 0.6 to 1.5
A non-staining paint composition characterized by mixing and mixing. (A) a weight average molecular weight of 5,000 to 80;
000, hydroxyl value is from 20 KOHmg / g to 150 KOHmg / g
A tertiary amino group-containing acrylic polyol, (B) an alkoxysilane compound having an alkylene oxide chain having 2 to 40 repeating units and a weight average molecular weight of 150 to 3500, (C) a general formula: And (D) a two-pack of a curing agent containing a polyisocyanate, and based on 100 parts by weight of a solid content at the time of use (A), (B) 0.1 to 20 parts by weight in terms of solid content, (C)
And 1 to 40 parts by weight, and (D) is mixed with the hydroxyl group of (A) so that the ratio of OH / NCO becomes 0.6 to 1.5. Paint composition. 5. The non-staining paint composition according to claim 1, wherein the alkylene oxide chain of the alkoxysilane compound (B) is a compound having an ethylene oxide chain and one end having a hydroxyl group. object. 6. The non-staining paint composition according to claim 1, wherein at least one of tetramethyl silicate and tetraethyl silicate is used as the alkyl silicate (C). 7. The non-staining paint composition according to claim 2, wherein the polyisocyanate is dissolved in a solvent containing at least 5% by weight of a ketone. 8. The non-staining paint composition according to claim 1, further comprising (E) a color pigment. 9. The non-staining paint composition according to claim 2, further comprising (E) a color pigment in the base material. 10. The matte non-staining paint composition according to claim 1, further comprising (F) an extender pigment. 11. The matte non-staining paint composition according to any one of claims 2 to 4, wherein the base material further comprises (F) an extender pigment.