JP5977005B2 - Light resistant paint - Google Patents

Description

  The present invention relates to a light-resistant paint, and more specifically, a water-dispersible composition comprising a polymer having an ultraviolet absorbing group and a polyurethane dispersion (hereinafter sometimes referred to as “PUD”). It relates to paint.

  When a resin product is used or stored for a long period of time, various performance deteriorations may occur due to ultraviolet exposure. Examples of the performance deterioration include a decrease in elasticity due to a decrease in molecular weight, a decrease in tensile strength, a decrease in physical properties such as generation of cracks, a deterioration in electrical properties, a decrease in gloss, coloring, fading, and discoloration. In order to improve such problems, for example, treatment with a paint or coating agent to which UV absorbers such as benzotriazole UV absorbers, benzophenone UV absorbers, salicylate UV absorbers, and triazine UV absorbers are added. Is done. In particular, high light resistance, water resistance, heat resistance, and weather resistance are required for coating materials used for building interior and exterior materials, base materials constituting solar cells, vehicle interior and exterior materials, marking films, furniture, and electrical products.

  However, since these ultraviolet absorbers are non-reactive low molecular compounds, there are problems such as bleed out from paint over time, volatilization and decomposition due to heat during drying and molding, and elution with solvents and chemicals. Therefore, it has been pointed out that the ultraviolet absorber is not sufficiently contained in the paint and the light resistance cannot be exhibited or maintained. Even if a large amount of the UV absorber is added to the coating material, the low molecular weight UV absorber is poorly compatible and therefore causes layer separation, resulting in a decrease in transparency and mechanical strength.

  In addition, paints and coating agents are being converted from conventional solvent types to water-based types with a low environmental load. However, in order to blend a large amount of the conventional ultraviolet absorber in the water-based paint, it is necessary to blend after dispersing in advance using a dispersant. For this reason, there is a problem that it takes time and effort to blend out and is easy to bleed out.

  Aqueous acrylic resins are widely used as paints because of their excellent weather resistance and toughness. However, when the acrylic resin alone is used, if the glass transition point (Tg) is increased, the film-forming property is lowered and cracks are likely to occur. Therefore, it is necessary to use a solvent in combination. On the other hand, when the glass transition point (Tg) of the acrylic resin is lowered, the tack becomes strong, so that there may be a problem that winding cannot be performed or durability is lowered. In order to improve these problems, an aqueous acrylic resin is used in combination with a PUD that is excellent in elasticity, adhesion, and wear resistance so as to have the advantages of both resins. For this reason, about the coating material containing water-based acrylic resin and PUD, it is desired that the compatibility of water-based acrylic resin and PUD is excellent. Further, when the aqueous acrylic resin and PUD are mixed, it is necessary that shock aggregation does not occur.

  From such a viewpoint, it is conceivable to polymerize a low molecular weight ultraviolet absorber having a reactive double bond (unsaturated bond) in the molecule to increase the molecular weight. However, even if such an ultraviolet absorber is polymerized alone, the compatibility of the aqueous acrylic resin and PUD cannot be improved. For this reason, benzophenone type UV absorbers with polymerizable groups and acrylic monomers are polymerized to improve non-bleed out properties, non-elution properties, and heat resistance, and to improve compatibility with added polymer materials. Attempts have been made (see Patent Document 1). However, this trial has problems that the effect of improving the compatibility with some polymer materials is insufficient and that it is difficult to apply to aqueous products.

  In addition, an aqueous emulsion type polymeric ultraviolet absorber has been reported (see Patent Document 2). However, since this polymer ultraviolet absorber needs to use an emulsifier in order to disperse in water, water resistance is insufficient, transparency may be lowered, and the emulsifier may bleed out. is there.

  There has also been a report of obtaining an ultraviolet absorption PUD using a polyester polyol obtained by adding a lactone to a benzotriazole type ultraviolet absorber (see Patent Document 3). However, since polyester polyester has a polyester structure, it may be inferior in weather resistance such as hydrolysis resistance.

Japanese Patent Application Laid-Open No. 3-28185 JP-A-6-73368 JP 2002-121253 A

  Therefore, in view of the problems of the conventional technology, the present invention has a problem that light resistance, non-bleed out property, compatibility, compared with the case where a conventional ultraviolet absorber is used. An object of the present invention is to provide a paint excellent in water resistance, transparency, and heat resistance, especially by suppressing photodegradation and improving durability by blending alone or with various resins.

  Therefore, as a result of intensive studies to solve the above problems, the present inventors have paid attention to the fact that a paint capable of solving the above problems can be provided by combining an ultraviolet absorbing polymer and a polyurethane dispersion, The present invention has been conceived based on such knowledge.

  Usually, a coating film forming element of a paint consists of a coating film forming main element such as a synthetic resin or oil, and a coating film forming subelement such as a plasticizer, a drying agent or a stabilizer, and a pigment. Although used, it has been found that a polymer composition comprising a combination of the ultraviolet-absorbing polymer (A) according to the present invention and a dispersion of polyurethane (B) can directly serve as the film-forming element. As described below, the present invention solves the conventional problems and provides more specific effects.

  Thus, according to the present invention, the following paints are provided.

  [1] A paint comprising an ultraviolet absorbing polymer (A) and a dispersion of polyurethane (B).

  [2] The ultraviolet absorbing polymer (A) comprises a compound (a) having a double bond and an ultraviolet absorbing group (hereinafter sometimes referred to as “compound (a)”), a double bond-containing component (h The coating material according to [1], which is a polymerization product obtained by polymerizing a polymerization component containing

  [3] The paint according to [1], wherein the compound (a) is represented by any one of the following general formulas (1) to (4).

(In the general formula (1), X represents a halogen, a hydrogen atom, or an alkyl group having 10 or less carbon atoms, R ₁ represents a hydrogen atom or an alkyl group having 10 or less carbon atoms, and R ₂ represents a single atom. A bond, an alkylene group having 10 or less carbon atoms, an oxyalkylene group having 10 or less carbon atoms, or a hydroxyoxyalkylene group having 10 or less carbon atoms, and R ₃ represents a hydrogen atom or a methyl group.

(In the general formula (2), X represents a halogen, a hydrogen atom, or an alkyl group having 10 or less carbon atoms, and R ₁ is a single bond, an alkylene group having 10 or less carbon atoms, or an oxyalkylene having 10 or less carbon atoms. Group or a hydroxyoxyalkylene group having 10 or less carbon atoms, and R ₂ represents a hydrogen atom or a methyl group.)

(In the general formula (3), X represents a halogen, a hydrogen atom, or an alkyl group having 10 or less carbon atoms, and R ₁ is a single bond, an alkylene group having 10 or less carbon atoms, or an oxyalkylene having 10 or less carbon atoms. Group or a hydroxyoxyalkylene group having 10 or less carbon atoms, and R ₂ represents a hydrogen atom or a methyl group.)

(In the general formula (4), R ₁ represents a single bond, an alkylene group having 20 or less carbon atoms, an oxyalkylene group having 20 or less carbon atoms, or a hydroxyalkoxyl group having 20 or less carbon atoms, and R ₂ represents hydrogen. An atom or a methyl group is shown, R < ₃ > -R < ₆ > shows a hydrogen atom, an alkyl group, or an alkoxyl group each independently.)

  [4] The [1], wherein the double bond-containing component (h) is at least one polymerization component selected from the group consisting of a styrene monomer, an acrylic acid monomer, a methacrylic acid monomer, and an acrylonitrile monomer. The paint described in 1.

  [5] The paint according to [1], wherein the proportion of the structural unit derived from the compound (a) contained in the ultraviolet absorbing polymer (A) is 1 to 80% by mass.

  [6] The ultraviolet absorbing polymer (A) has a glass transition point (Tg) of -20 to 160 ° C, preferably -10 to 150 ° C, and a weight average molecular weight (Mw) of 1,000 to 1,500,000. The paint according to the above [1], which preferably has 5,000 to 100,000 and an acid value of 2 to 200 mgKOH / g, preferably 5 to 100 mgKOH, and can be dissolved or dispersed in water.

  [7] The polyurethane (B) comprises a compound (b) having an active hydrogen-containing group and an anionic hydrophilic group (excluding a hydrogen group), a polyol (c) and / or a polyamine (d), and a polyisocyanate. The paint according to [1], which is a reaction product obtained by reacting a reaction component containing (e).

  [8] The paint according to [7], wherein the reaction component further contains a short-chain diol component (f) and / or a short-chain diamine component (g).

  [9] The polyurethane (B) is a total activity of the compound (b), the polyol (c), the polyamine (d), the short chain diol component (f), and the short chain diamine component (g). A hydrogen-containing group (excluding an anionic hydrophilic group) (1) and an isocyanate group (2) of the polyisocyanate (e) in an equivalent ratio of (1) / (2) = 0.9 to 1.5 The paint according to [7], which is a reaction product obtained by reacting.

  [10] The paint according to any one of [7] or [9], wherein the compound (b) is represented by the following general formula (5).

_{(HO-R'-) n -R- (} R "-X m) l ··· (5)
(In the general formula (5), R represents an alkylene group, a cycloalkyl ring, an aromatic ring, an amine structure, or a heterocyclic ring, R ′ represents an alkylene group, a cycloalkyl ring, or an aromatic ring; R ″ represents a single bond, an alkylene group, a cycloalkyl ring, or an aromatic ring, X represents —COOH, —SO ₃ H, or —PO ₃ H ₂ , n represents 1 or 2, m Represents 1 or 2, and l represents an integer of 1 to 3.)
[11] The paint according to any one of [7], [9] or [10], wherein the compound (b) is dimethylolalkanoic acid.

  [12] Any of [1], [7] or [9] above, wherein the polyurethane (B) has a weight average molecular weight of 1,000 to 500,000 and an average particle size of the dispersion of 1 nm to 1 μm. The paint according to crab.

  [13] The paint according to [1], wherein the content of the ultraviolet absorbing polymer (A) with respect to the total solid content is 0.1 to 50% by mass.

  [14] A paint obtained by reacting the ultraviolet absorbing polymer (A) with the polyurethane (B).

  [15] At least one crosslinking agent selected from the group consisting of an epoxy compound, a carbodiimide compound, an aziridine compound, an oxazoline compound, and an isocyanate compound is added to the ultraviolet absorbing polymer (A) and the polyurethane (B). The paint according to [14], which is obtained by performing the treatment.

  [16] The coating material according to [1], which is manufactured by a manufacturing method including a step of mixing the solution or water dispersion of the ultraviolet absorbing polymer (A) and the dispersion of the polyurethane (B).

  [17] Manufactured by a production method comprising a step of adding a solution or an aqueous dispersion of the ultraviolet absorbing polymer (A) to a urethane prepolymer obtained in an intermediate stage of the step of preparing a dispersion of the polyurethane (B). The paint according to [1].

  Moreover, according to this invention, the manufacturing method of the coating material shown below is provided.

[18] The method for producing a paint according to [1] above,
A preparation step A for preparing a solution or an aqueous dispersion of the ultraviolet absorbing polymer (A);
Preparation step B for preparing a dispersion of polyurethane (B),
A method for producing a coating material comprising a mixing step C in which a solution or an aqueous dispersion of an ultraviolet absorbing polymer (A) obtained in the preparation step A and a dispersion of a polyurethane (B) obtained in the preparation step B are mixed.

[19] The method for producing a paint according to [1],
In the preparation step B, a solution or an aqueous dispersion of the UV-absorbing polymer (A) obtained in the preparation step A is added to the urethane prepolymer obtained in the intermediate stage of preparing the dispersion of the polyurethane (B). A method for producing a coating material comprising the addition step D.

  The paint of the present invention is superior in light resistance, non-bleed out property, compatibility, water resistance, transparency, and heat resistance as compared with the case of using a conventional ultraviolet absorber, and particularly has a remarkable effect on light resistance. In addition, it is a paint that can suppress the photodegradation of resin products and is improved in durability by being alone or blended with various resins, and solves the problems of the prior art. The paint of the present invention can also be used as a primer paint.

2 is an ultraviolet absorption spectrum measured for the film obtained in Example 1. It is the infrared absorption spectrum measured about the film obtained in Example 1. FIG.

  Embodiments of the present invention will be described below. However, the present invention is not limited to the following embodiments. The coating material of the present invention has an ultraviolet absorbing function, and is preferably a stable aqueous dispersion comprising an ultraviolet absorbing polymer (A) and a dispersion of polyurethane (B). The details will be described below.

  Moreover, about coating-film formation subelements, such as a plasticizer and a stabilizer, it can mix | blend arbitrarily as needed. Furthermore, the pigment can be arbitrarily selected according to the application of the paint. The performance of the polymer composition composed of the dispersion of the ultraviolet absorbing polymer (A) and the polyurethane (B) according to the present invention is not inhibited by the coating film forming subelement and the pigment.

(Ultraviolet absorbing polymer (A))
The ultraviolet absorbing polymer (A) is a polymerization component comprising a compound (a) having a reactive double bond (unsaturated bond) and an ultraviolet absorbing group in the molecule, and a double bond (unsaturated bond) -containing component. Is obtained by polymerizing. The double bond of the compound (a) may be any reactive double bond that can be polymerized by an ordinary polymerization method such as radical polymerization, cationic polymerization, and anionic polymerization. From the viewpoints of reactivity and availability or ease of synthesis, an acrylic or methacrylic double bond is preferred. Hereinafter, “acryl” and “methacryl” are also referred to as “(meth) acryl”.

  Examples of the structure of the ultraviolet absorbing group of the compound (a) include the structure of a commonly used ultraviolet absorbent. Specific examples of such ultraviolet absorbers include benzotriazole, benzophenone, salicylate, and triazine ultraviolet absorbers. In addition, the compound (a) may contain an ultraviolet absorbing group having a structure other than the structure of these ultraviolet absorbents.

  Examples of the compound (a) when the structure of the ultraviolet absorbing group is that of a benzotriazole-based ultraviolet absorber include those having the structure represented by the general formula (1). Specific examples of the compound (a) represented by the general formula (1) include 2- [2′-hydroxy-5 ′-(methacryloyloxyethyl) phenyl] -2H-benzotriazole, 2- [2′- Hydroxy-3'-t-butyl-5 '-(methacryloyloxyethyl) phenyl] -2H-benzotriazole, 2- [2'-hydroxy-3'-t-butyl-5'-(methacryloyloxypropyl) phenyl] -2H-benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) -5- (2'-methacryloyloxyethyl) -2H-benzotriazole, 2-[(2'-hydroxy-5 '-( And methacryloyloxyethyl) phenyl) -5-chloro] -2H-benzotriazole. These compounds (a) can be used individually by 1 type or in combination of 2 or more types.

  Examples of the compound (a) in the case where the structure of the ultraviolet absorbing group is that of a benzophenone ultraviolet absorber include those having the structure represented by the general formula (2). Specific examples of the compound (a) represented by the general formula (2) include 2-benzoyl-5- (2′-hydroxy-3′-methacryloyloxypropoxy) -phenol, 2-benzoyl-5- (2 '-Methacryloyloxyethoxy) -phenol, 2-benzoyl-5- (2'-acryloyloxyethoxy) -phenol, 2-benzoyl-5- (2'-acryloyloxyethoxy) -6-tert-butyl-phenol, etc. Can be mentioned. These compounds (a) can be used individually by 1 type or in combination of 2 or more types.

  Examples of the compound (a) in the case where the structure of the ultraviolet absorbing group is that of a salicylate ultraviolet absorber include those having the structure represented by the general formula (3). Further, examples of the compound (a) in the case where the structure of the ultraviolet absorbing group is that of a triazine-based ultraviolet absorbent include those having a structure represented by the general formula (4). Specific examples of the compound (a) represented by the general formula (4) include 2,4-diphenyl-6- [2-hydroxy-4- (2-acryloyloxyethoxy)]-1,3,5- Triazine, 2,4-bis (2-methylphenyl) -6- [2-hydroxy-4- (3-acryloyloxy-2-hydroxypropoxy)]-1,3,5-triazine, 2,4-diphenyl And -6- [2-hydroxy-4- (11-acryloyloxy-undecyloxy) phenyl] -1,3,5-triazine. These compounds (a) can be used individually by 1 type or in combination of 2 or more types.

  Of these ultraviolet absorbing group structures, as will be described later, the structure of a benzotriazole-based ultraviolet absorber is preferable in order to obtain a remarkable effect in all performances.

  As the double bond-containing component (h) to be copolymerized with the compound (a), a (meth) acrylic acid monomer is suitable. Specific examples of such (meth) acrylic acid monomers include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n- Butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, amyl (meth) acrylate, isoamyl (meth) acrylate, heptyl (meth) acrylate, n-octyl ( (Meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, isodecyl (meth) acrylate, Sil (meth) acrylate, tridecyl (meth) acrylate, n-lauryl (meth) acrylate, n-stearyl (meth) acrylate, isostearyl (meth) acrylate, dicyclopentanyl (meth) acrylate, isobornyl (meth) acrylate, Phenoxyethyl (meth) acrylate etc. can be mentioned. In addition, as a double bond containing component (h), a styrene-type monomer and an acrylonitrile-type monomer can also be used. These double bond-containing components (h) can be used singly or in combination of two or more.

  The higher the proportion of the structural unit derived from the compound (a) contained in the ultraviolet absorbing polymer (A), the higher the ultraviolet absorbing effect. However, when the content ratio of the structural unit derived from the compound (a) is too high, the stability of the ultraviolet absorbing polymer (A) during synthesis and the compatibility with the polyurethane (B) tend to decrease. For this reason, it is preferable that the ratio of the structural unit derived from the compound (a) contained in an ultraviolet absorption type polymer (A) is 1-80 mass%, Most preferably, it is 30-80 mass%, 40- More preferably, it is 70 mass%.

  By using a monomer having a hydrophilic group such as a carboxyl group as a polymerization component other than the compound (a), an ultraviolet absorbing polymer (A) imparted with water dispersibility can be obtained. In addition, (meth) acrylic acid etc. can be mentioned as a monomer which has a hydrophilic group. In the ultraviolet absorbing polymer (A), the higher the acid value, the higher the water dispersibility. However, a coating film formed using a paint containing the ultraviolet absorbing polymer (A) having an acid value that is too high tends to have poor water resistance or become too hard to lower the paint performance. For this reason, it is preferable that the acid value of an ultraviolet absorption type polymer (A) is 2-200 mgKOH / g, Most preferably, it is 5-100 mgKOH / g, and it is further more preferable that it is 10-90 mgKOH / g.

  When an ester of (meth) acrylic acid and a long-chain alcohol is used as the double bond-containing component (h), the glass transition point (Tg) of the resulting ultraviolet absorbing polymer (A) tends to be lowered. When such an ultraviolet-absorbing polymer (A) having a low glass transition point (Tg) is used, it is possible to form a paint having excellent film-forming properties capable of forming a coating film with improved flexibility. On the other hand, when an ester of (meth) acrylic acid and a short-chain alcohol, (meth) acrylic acid, styrene, or acrylonitrile is used as the double bond-containing component (h), the glass of the ultraviolet absorbing polymer (A) obtained. The transition point (Tg) tends to increase. When such an ultraviolet absorbing polymer (A) having a high glass transition point (Tg) is used, a paint capable of forming a coating film with improved durability and toughness can be obtained. That is, by selecting the type and ratio of the polymerization component so that the glass transition point (Tg) of the ultraviolet absorbing polymer (A) is an appropriate numerical value, a coating film having high toughness can be formed. A paint having excellent film-forming properties can be obtained. Specifically, it is preferable to use two or more types of (meth) acrylic acid monomers as the double bond-containing component (h). Moreover, it is preferable that the glass transition point (Tg) of an ultraviolet absorption type polymer (A) is -20-160 degreeC. When the glass transition point (Tg) of the ultraviolet absorbing polymer (A) is more than 160 ° C., the film forming property and the compatibility tend to be lowered. On the other hand, when the glass transition point (Tg) of the UV-absorbing polymer (A) is less than −20 ° C., tackiness is likely to occur at the time of coating film formation, and durability such as heat resistance tends to decrease. Particularly preferable glass transition point (Tg) is −10 to 150 ° C., and two or more kinds of (meth) acrylic acid monomers, specifically, esters of (meth) acrylic acid and long-chain alcohols, or ( By using a combination of an ester of (meth) acrylic acid and a short-chain alcohol, it is possible to form a coating film having both toughness and film-forming properties and excellent light resistance.

  The polymerization component used to obtain the ultraviolet absorbing polymer (A) includes the ultraviolet absorbing function, durability, water dispersibility, and compatibility of the resulting ultraviolet absorbing polymer (A) as long as the properties are not impaired. Further, a monomer (polymerization component) having “other functions” such as light stability and an antioxidant function may be contained. Specific examples of the monomer having such “other functions” include 4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloylamino-2,2,6. , 6-Tetramethylpiperidine, 4- (meth) acryloyloxy-1,2,2,6,6-pentamethylpiperidine, 4- (meth) acryloylamino-1,2,2,6,6-pentamethylpiperidine Etc. These monomers are partial structures of hindered amine light stabilizers.

(Method for producing UV-absorbing polymer (A))
The ultraviolet absorbing polymer (A) is a conventionally known polymerization method such as emulsion polymerization, suspension polymerization, solution polymerization, or bulk polymerization of a polymerization component containing the compound (a) and the double bond-containing component (h). Can be obtained by polymerization. For example, in solution polymerization, a polymerization component may be polymerized in an appropriate solvent in the presence of a polymerization initiator. In solution polymerization, since an emulsifier is usually not used, the compatibility, transparency, and water resistance of the ultraviolet absorbing polymer (A) to be obtained are improved.

  The kind of solvent used in the solution polymerization is not particularly limited as long as it does not adversely affect the polymerization reaction. Specific examples of the solvent include water; methanol, ethanol, isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, isobutyl alcohol, tert-butyl alcohol, n-pentyl alcohol, ethyl cellosolve, butyl cellosolve, propylene glycol monomethyl ether, ethylene Alcohol solvents such as glycol, propylene glycol and diethylene glycol; aliphatic hydrocarbon solvents such as petroleum ether, hexane and heptane; aromatic hydrocarbon solvents such as benzene, toluene and xylene; diethyl ether, dibutyl ether and tetrahydrofuran (THF), ether solvents such as dioxane; methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-heptanone, 3-heptanone, 2-octa Ketone solvents such as ethyl, cyclohexanone, cyclopentanone and methyl isobutyl ketone; ester solvents such as ethyl acetate, propyl acetate and butyl acetate; N, N-dimethylformamide (DMF), N, N-dimethylacetamide, N- Examples include amide solvents such as methylpyrrolidone (NMP). Among these, alcohol-based solvents, ether-based solvents, and amide-based solvents that are miscible with water are preferable because the resulting UV-absorbing polymer (A) becomes water-dispersible. The amount of solvent used is appropriately determined depending on the conditions of the polymerization reaction. Usually, it is about 0.1 to 100 times, preferably about 0.2 to 20 times by mass ratio to the polymerization component. In addition, these solvents can be used individually by 1 type or in combination of 2 or more types.

  Conventional polymerization initiators can be used. Specific examples of the polymerization initiator include peroxides such as benzoyl peroxide, dibutyl peroxide and cumene hydroperoxide; azo polymerization such as azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile). Mention may be made of initiators. These polymerization initiators can be used singly or in combination of two or more. Although the usage-amount of a polymerization initiator is not specifically limited, Usually, it is about 0.1-10 mass% with respect to a polymerization component.

  The temperature of the polymerization reaction is appropriately set depending on the reaction conditions. Usually, the temperature may be any temperature from room temperature (25 ° C.) to the boiling point of the solvent used. Moreover, in order to adjust the polymerization degree of the resulting ultraviolet absorbing polymer (A), a chain transfer agent such as mercaptans or a polymerization inhibitor such as hydroquinone may be added to the polymerization reaction system.

  The weight-average molecular weight (Mw) of the ultraviolet absorbing polymer (A) thus obtained satisfies various performances such as non-bleed out properties, heat resistance, durability, water dispersibility, compatibility, and coating film performance. Therefore, it is preferably 1,000 to 1,500,000, and more preferably 5,000 to 100,000. In the present specification, “weight average molecular weight (Mw)” and “number average molecular weight (Mn)” mean values in terms of polystyrene measured by gel permeation chromatography (GPC) unless otherwise specified. .

  The solution of the ultraviolet absorbing polymer (A) obtained by solution polymerization can be used as, for example, an ultraviolet absorber by adding it to a polymer product in a solution state. Further, even when a solvent obtained by evaporating a solvent from a solution of the ultraviolet absorbing polymer (A) is kneaded into a polymer product, it can be used as an ultraviolet absorber.

  The function of the ultraviolet absorbing polymer (A) is more effectively exhibited by using an aqueous dispersion. To prepare an aqueous dispersion of the ultraviolet absorbing polymer (A), a neutralizing agent is added to the solution of the ultraviolet absorbing polymer (A) to form a salt of the ultraviolet absorbing polymer (A), and then water is added. Can be inserted. The neutralizing agent may be dissolved or dispersed in water.

  Specific examples of the neutralizing agent include ammonia, ethylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N-phenyldiethanolamine, monoethanolamine, dimethylethanolamine, diethylethanolamine, Organic amines such as morpholine, N-methylmorpholine and 2-amino-2-ethyl-1-propanol; alkali metals such as lithium, potassium and sodium; inorganic alkalis such as lithium hydroxide, sodium hydroxide and potassium hydroxide Can be mentioned. Usually, the addition amount of the neutralizing agent is preferably 0.8 to 1 equivalent to the carboxyl group of the ultraviolet absorbing polymer (A), but the acid value of the ultraviolet absorbing polymer (A) is high. It is also possible to reduce the amount of neutralizing agent added.

  The aqueous dispersion of the UV-absorbing polymer (A) is an aqueous dispersion containing no volatile organic compound (VOC) by removing the solvent used during polymerization by removing the solvent by a method such as distillation under reduced pressure, if necessary. It can be. By making the ultraviolet absorbing polymer (A) into an aqueous dispersion not containing VOC, the dispersion stability of PUD (B) can be improved when blended with PUD (B). Moreover, the working environment at the time of using the obtained coating material as a coating material is improved significantly.

(Dispersion of polyurethane (B))
The polyurethane (B) includes a compound (b) having an active hydrogen-containing group and an anionic hydrophilic group (excluding a hydroxyl group), a polyol (c) and / or a polyamine (d), and a polyisocyanate (e). Obtained by reacting reaction components. More preferably, the polyurethane (B) is a sum of the compound (b), the polyol (c), and the polyamine (d), and the short-chain diol component (f) and the short-chain diamine component (g) used as necessary. The active hydrogen-containing group (excluding an anionic hydrophilic group) (1) and the isocyanate group (2) of the polyisocyanate (e) are equivalent to (1) / (2) = 0.9 to 1.5 It is obtained by reacting at a ratio (molar ratio).

  In the present specification, “polyurethane” means a general term for polyurethane and polyurethane-urea. The “polyurethane” may be a product obtained by reacting an amine component as necessary. In addition, the “active hydrogen-containing group” in the present specification means a functional group having active hydrogen having reactivity with an isocyanate group. Specific examples of such “active hydrogen-containing group” include a hydroxyl group, a mercapto group, a carboxyl group, and an amino group.

  The compound (b) having an active hydrogen-containing group and an anionic hydrophilic group is a component that imparts water dispersibility to the polyurethane (B) obtained by the anionic hydrophilic group. That is, polyurethane (B) can be a stable self-emulsifying dispersion without using an emulsifier. Examples of the compound (b) include compounds represented by the general formula (5). Specifically, a sulfonic acid compound, a carboxylic acid compound, a phosphoric acid compound, and the like can be used as the compound (b). These compounds (b) can be used individually by 1 type or in combination of 2 or more types.

  Specific examples of the sulfonic acid compound include N, N-bis (2-hydroxyethyl) -2-aminoethanesulfonic acid. Specific examples of the carboxylic acid compounds include dimethylolalkanoic acids such as dimethylolpropanoic acid and dimethylolbutanoic acid; alkylene oxide low-mole adducts of dimethylolalkanoic acid (number average molecular weight less than 500 by terminal functional group determination); Ε-caprolactone low molar adduct of dimethylolalkanoic acid (number average molecular weight of less than 500 by terminal functional group determination); half ester derived from dimethylolalkanoic acid anhydride and glycerin; hydroxyl group of dimethylolalkanoic acid And a compound obtained by subjecting a monomer having an unsaturated bond and a monomer having a carboxyl group and an unsaturated bond to a free radical reaction. Of these, dimethylolpropanoic acid and dimethylolalkanoic acid such as dimethylolbutanoic acid are preferred from the viewpoints of availability, ease of adjustment of acid value, and the like. The content of the compound (b) in the reaction component is set from the viewpoint of achieving both water dispersibility and water resistance of the resulting polyurethane (B). More specifically, the content of the compound (b) in the reaction component is preferably such that the acid value of the resulting polyurethane (B) is 2 to 200 mgKOH / g, and is 5 to 100 mgKOH / g. More preferably, it is an amount.

  The polyol (c) is a component that can constitute the main skeleton of the polyurethane (B) alone or in combination with the polyamine (d). As the polyol (c), a conventionally known polyol used for urethane synthesis can be used. Specific examples of the polyol (c) include polyester polyol, polyether polyol, polycarbonate polyol, and other polyols.

  Polyester polyols include aliphatic dicarboxylic acids (eg succinic acid, adipic acid, sebacic acid, glutaric acid, azelaic acid etc.) and / or aromatic dicarboxylic acids (eg isophthalic acid, terephthalic acid etc.), low Molecular weight glycol (for example, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, 1,6-hexamethylene glycol, neopentyl glycol, 1,4-bishydroxymethylcyclohexane, etc. ) And those obtained by condensation polymerization.

  Specific examples of such polyester polyols include polyethylene adipate diol, polybutylene adipate diol, polyhexamethylene adipate diol, polyneopentyl adipate diol, polyethylene / butylene adipate diol, polyneopentyl / hexyl adipate diol, poly-3- Examples thereof include methylpentane adipate diol, polybutylene isophthalate diol, polycaprolactone diol, and poly-3-methylvalerolactone diol.

  Specific examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and random / block copolymers thereof.

  Specific examples of the polycarbonate polyol include polytetramethylene carbonate diol, polypentamethylene carbonate diol, polyneopentyl carbonate diol, polyhexamethylene carbonate diol, poly (1,4-cyclohexanedimethylene carbonate) diol, and random / Examples thereof include a block copolymer.

  Specific examples of other polyols include dimer diol, polybutadiene polyol and its hydrogenated product, polyisoprene polyol and its hydrogenated product, acrylic polyol, epoxy polyol, polyether ester polyol, siloxane-modified polyol, α, ω-polymethyl Examples thereof include methacrylate diol and α, ω-polybutyl methacrylate diol.

  The number average molecular weight (Mn, determined by terminal functional group determination) of the polyol (c) is not particularly limited, but is preferably 500 to 3,000. If the number average molecular weight (Mn) of the polyol (c) is more than 3,000, the cohesive force of the urethane bond is hardly expressed and the mechanical properties tend to be lowered. In addition, a crystalline polyol having a number average molecular weight of more than 3,000 may cause a whitening phenomenon when formed into a film. In addition, a polyol (c) can be used individually by 1 type or in combination of 2 or more types.

  The polyamine (d) is a component that can constitute the main skeleton of the polyurethane (B) alone or in combination with the polyol (c). Specific examples of the polyamine (d) include long chain alkylene diamines, polyoxyalkylene diamines, terminal amine polyamides, and siloxane-modified polyamines.

  As the polyisocyanate (e), conventionally known polyisocyanates used in the production of polyurethane can be used. Specific examples of the polyisocyanate (e) include toluene-2,4-diisocyanate, 4-methoxy-1,3-phenylene diisocyanate, 4-isopropyl-1,3-phenylene diisocyanate, 4-chloro-1,3-phenylene. Diisocyanate, 4-butoxy-1,3-phenylene diisocyanate, 2,4-diisocyanate diphenyl ether, 4,4′-methylenebis (phenylene isocyanate) (MDI), durylene diisocyanate, tolidine diisocyanate, xylylene diisocyanate (XDI), 1, Aromatic diisocyanates such as 5-naphthalene diisocyanate, benzidine diisocyanate, o-nitrobenzidine diisocyanate, 4,4′-diisocyanate dibenzyl; methylene diisocyanate 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,10-decamethylene diisocyanate and other aliphatic diisocyanates; 1,4-cyclohexylene diisocyanate, 4,4-methylenebis (cyclohexyl isocyanate), 1, Cycloaliphatic diisocyanates such as 5-tetrahydronaphthalene diisocyanate, isophorone diisocyanate, hydrogenated MDI, hydrogenated XDI; polyurethanes obtained by reacting these diisocyanates with low molecular weight polyols or polyamines so that the ends are isocyanates Examples include prepolymers. From the viewpoint of obtaining a paint excellent in weather resistance, aliphatic diisocyanate and alicyclic diisocyanate are preferable.

In addition, as a reaction component for obtaining a polyurethane (B), it is also preferable to use a short chain diol component (f) and / or a short chain diamine component (g) as needed. Specific examples of the short-chain diol component (f) include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, 1,6-hexamethylene glycol, neopentyl glycol and the like. Aliphatic glycol and its alkylene oxide low molar adduct (number average molecular weight less than 500 by terminal functional group determination); 1,4-bishydroxymethylcyclohexane, 2-methyl-1,1-cyclohexanedimethanol and other alicyclic glycols And its alkylene oxide low molar adduct (number average molecular weight less than 500, same as above); aromatic glycol such as xylylene glycol and its alkylene oxide low mole adduct (number average molecular weight less than 500, same as above); bisphenol A, thiobisphenol, Sulfonbispheno Bisphenols and alkylene oxide low molar adducts such as Le (number average molecular weight of less than 500, supra); and alkyl dialkanolamine such as alkyl diethanolamine C ₁ -C ₁₈ and the like.

  A polyhydric alcohol compound can also be used as the short-chain diol component (f). Specific examples of such polyhydric alcohol compounds include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, tris- (2-hydroxyethyl) isocyanurate, 1,1,1-trimethylolethane, 1, Examples include 1,1-trimethylolpropane. In addition, when using a polyol as a short chain diol component (f), a diol compound is preferable as such a polyol. These short chain diol components (f) can be used singly or in combination of two or more.

  Specific examples of the short chain diamine component (g) include aliphatic diamine compounds such as methylene diamine, ethylene diamine, trimethylene diamine, hexamethylene diamine and octamethylene diamine; phenylene diamine, 3,3′-dichloro-4,4 ′. -Aromatic diamine compounds such as diaminodiphenylmethane, 4,4′-methylenebis (phenylamine), 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylsulfone; cyclopentyldiamine, cyclohexyldiamine, 4,4′-diamino Examples thereof include alicyclic diamine compounds such as dicyclohexylmethane, 1,4-diaminocyclohexane and isophoronediamine. Furthermore, hydrazines such as hydrazine, carbodihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, phthalic acid dihydrazide can be used as the short-chain diamine component (g). In addition, when using the short chain diamine component (g) as a chain extender of the water-dispersed prepolymer, the short chain diamine component (g) is preferably water-soluble. In addition, when using a polyamine as a short chain diamine component (g), as such a polyamine, a diamine compound is preferable. These short chain diamine components (g) can be used singly or in combination of two or more.

(Production method of polyurethane (B))
The polyurethane (B) can be produced by a conventionally known polyurethane production method. Specifically, first, compound (b), polyol (c) and / or polyamine (d), polyisocyanate (e), in the presence or absence of an organic solvent containing no active hydrogen in the molecule, A reaction product (for example, a prepolymer (hereinafter sometimes referred to as “prepolymer”)) is obtained by reacting a reaction component comprising a short-chain diol component (f) used as a chain extender as necessary. . In general, the reaction component may be a blended composition in which a prepolymer having a terminal isocyanate group is formed. Moreover, what is necessary is just to make it react until it becomes theoretical isocyanate% by 20-150 degreeC normally by the one shot method or a multistage method, Preferably it is 60-110 degreeC. As a prepolymer to which a solution or an aqueous dispersion of an ultraviolet absorbing polymer (A) for preparing a polymer product is added, those having a weight average molecular weight of 500 to 500,000 are preferable.

  If water and a neutralizing agent are added and emulsified to the obtained reaction product (prepolymer), a dispersion (aqueous dispersion) of polyurethane (B) can be obtained. As the neutralizing agent, organic amines, alkali metals, and inorganic alkalis similar to those used when preparing the aqueous dispersion of the ultraviolet absorbing polymer (A) can be used. If necessary, the prepolymer may be reacted with the short-chain diamine component (g) to extend the chain so as to have a desired molecular weight. Further, the total active hydrogen-containing groups (excluding anionic hydrophilic groups) of the compound (b), polyol (c), polyamine (d), short-chain diol component (f), and short-chain diamine component (g) ( It is preferable to react 1) and the isocyanate group (2) of the polyisocyanate (e) at an equivalent ratio (molar ratio) of (1) / (2) = 0.9 to 1.5. Furthermore, polyurethane (B) can also be obtained by removing the solvent as necessary.

  The weight average molecular weight (Mw) of the polyurethane (B) obtained as described above is 1,000 to 500,000, and the properties such as flexibility, adhesiveness, and abrasion resistance of the polyurethane are more effective. In order to be exhibited, it is preferable.

  In the present invention, a catalyst can be used as necessary in the urethane synthesis. For example, salts of metals and organic and inorganic acids such as dibutyltin laurate, dioctyltin laurate, stannous octoate, zinc octylate, tetra-n-butyl titanate, and organic amine derivatives such as organometallic derivatives, triethylamine, diaza Bicycloundecene catalysts and the like can be mentioned.

  Polyurethane (B) may be synthesized without using a solvent or may be synthesized with an organic solvent. As the organic solvent, an organic solvent inert to the isocyanate group or an organic solvent less active than the reaction component with respect to the isocyanate group can be used. Specific examples of the organic solvent include ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; toluene, xylene, swazol (trade name, manufactured by Cosmo Oil Co., Ltd.), Solvesso (trade name, manufactured by Exxon Chemical) Aromatic hydrocarbon solvents; aliphatic hydrocarbon solvents such as n-hexane; alcohol solvents such as methanol, ethanol and isopropyl alcohol; ether solvents such as dioxane and tetrahydrofuran; ethyl acetate, butyl acetate, isobutyl acetate, etc. Ester solvents; glycol ether ester solvents such as ethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate, 3-methyl-3-methoxybutyl acetate, ethyl-3-ethoxypropionate Dimethylformamide, amide solvents such as dimethylacetamide; lactams solvents such as N- methyl-2-pyrrolidone and the like. Among these, methyl ethyl ketone, ethyl acetate, acetone, and tetrahydrofuran are preferable in view of ease of solvent recovery, solubility of the reaction components, reactivity, boiling point, and emulsification dispersibility in water.

  In the urethane synthesis, when an isocyanate group remains at the end of the polymer, it is also preferable to perform a termination reaction of the isocyanate group. The termination reaction of the isocyanate group can be performed using a compound having reactivity with the isocyanate group. As such a compound, a monofunctional compound such as monoalcohol or monoamine; a compound having two kinds of functional groups having different reactivity with respect to isocyanate can be used. Specific examples of such compounds include monoalcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, tert-butyl alcohol; monoethylamine, n-propylamine, diethylamine And monoamines such as di-n-propylamine and di-n-butylamine; alkanolamines such as monoethanolamine and diethanolamine. Of these, alkanolamine is preferable because of easy control of the reaction.

(Polymer composition and production method thereof)
The coating material of this invention can be manufactured by mixing the solution or water dispersion of an ultraviolet absorption type polymer (A), and the dispersion of a polyurethane (B). Moreover, it is also a preferable aspect to mix with the solution or aqueous dispersion of the ultraviolet absorbing polymer (A) in the course of preparing the dispersion of polyurethane (B). More specifically, (1) after completion of the prepolymer reaction of polyurethane (B), before emulsifying (dispersing) the prepolymer in water, or (2) emulsifying (dispersing) the prepolymer in water. A solution or an aqueous dispersion of the ultraviolet absorbing polymer (A) is added at a later stage and before the chain extension reaction, and then the chain extension reaction may be performed as necessary. As described above, when a solution or an aqueous dispersion of the ultraviolet absorbing polymer (A) is added and mixed in the course of preparing the dispersion of the polyurethane (B), shock aggregation hardly occurs. Further, the compatibility between the ultraviolet absorbing polymer (A) and the polyurethane (B) is further improved. And the coating material obtained by doing in this way has high transparency, and can form a highly glossy coating film.

  The proportion of the ultraviolet absorbing polymer (A) contained in the paint of the present invention is preferably 0.1 to 50% by mass, more preferably 1 to 50% by mass, based on the total solid content in the paint. preferable. In addition, the paint of the present invention includes conventionally known additives such as an antioxidant, a light stabilizer, a flame retardant, an antistatic agent, a filler, and a colorant as long as the water dispersion stability and compatibility are not impaired. Can be added to improve performance, or to impart functionality or design.

  A paint capable of forming a coating film with further improved durability is obtained by reacting the ultraviolet absorbing polymer (A) and the polyurethane (B) alone or in combination with various resins. be able to. In particular, a crosslinking agent capable of reacting with a carboxyl group present in the molecules of the ultraviolet absorbing polymer (A) and the polyurethane (B) is used to cause the ultraviolet absorbing polymer (A) and the polyurethane (B) to undergo a crosslinking reaction. Is preferred.

  As the crosslinking agent, conventionally known crosslinking agents such as an oxazoline compound, an aqueous epoxy compound, an aqueous carbodiimide compound, an aziridine compound, an aqueous isocyanate compound, and a metal complex crosslinking agent can be used. Among these crosslinking agents, epoxy compounds, carbodiimide compounds, aziridine compounds, oxazoline compounds, and isocyanate compounds are preferable. Examples of commercially available epoxy compounds that can be used as a cross-linking agent include “jER” (manufactured by Mitsubishi Chemical Corporation). Examples of commercially available carbodiimide compounds include “carbodilite” (manufactured by Nisshinbo Chemical Co., Ltd.). Examples of commercially available products of the aziridine compound include “Chemite” (manufactured by Nippon Shokubai Co., Ltd.). Examples of commercially available oxazoline compounds include “Epocross” (manufactured by Nippon Shokubai Co., Ltd.). Examples of commercially available isocyanate compounds include “Duranate” (manufactured by Asahi Kasei Chemicals Corporation).

  These crosslinking agents are effective in improving heat resistance and weather resistance if they are in appropriate amounts. However, if the amount of the crosslinking agent used is too large, the coating may become brittle. For this reason, it is preferable that the usage-amount of a crosslinking agent shall be 40 mass parts or less with respect to 100 mass parts of resin components in a coating material, and it is more preferable to set it as 0.5-10 mass parts.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples. In the examples and comparative examples, “parts” and “%” are based on mass unless otherwise specified.

(1) <Synthesis of UV-absorbing polymer (A)>
[Synthesis Example A1: Benzotriazole type polymer (solution)]
A reaction vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen blowing tube, and a manhole was prepared. After replacing the inside of the reaction vessel with nitrogen gas, 100 g of methyl ethyl ketone (MEK) and 2- [2′-hydroxy-5 ′-(methacryloyloxyethyl) phenyl] -2H-benzotriazole (trade name, manufactured by Otsuka Chemical Co., Ltd.) 50 g of “RUVA-93” (hereinafter referred to as “(a) -1”) was charged and heated to 60 ° C. in a nitrogen atmosphere. A mixture of 38 g of methyl methacrylate, 5 g of methacrylic acid, 3 g of hydroxyethyl methacrylate, 3 g of butyl acrylate, 1 g of ethyl acrylate, and 2 g of 2,2′-azobis (2,4-dimethylvaleronitrile) was prepared. Half of the mixture was added to the reaction vessel, and the other half was dropped into the reaction vessel with a dropping funnel over 1 hour. After the dropwise addition, the reaction is allowed to proceed for 6 hours, and an ultraviolet-absorbing polymer having an acid value of 32.6 mgKOH / g, a weight average molecular weight (Mw) of 37,000, and a number average molecular weight (Mn) of 15,000 A solution (solid concentration 50%) was obtained. Table 1 shows the properties of the ultraviolet absorbing polymer solution.
[Synthesis Example A2: Benzotriazole type polymer (solution)]
A UV-absorbing polymer solution (solid content concentration 50%) was obtained in the same manner as in Synthesis Example A1 except that the formulation shown in Table 1 was used.
[Synthesis Example A3: Benzotriazole type polymer (solution)]
A UV-absorbing polymer solution (solid content concentration 50%) was obtained in the same manner as in Synthesis Example A1 except that the formulation shown in Table 1 was used.
[Synthesis Example A4: Benzotriazole type polymer (solution)]
A UV-absorbing polymer solution (solid content concentration 50%) was obtained in the same manner as in Synthesis Example A1 except that the formulation shown in Table 1 was used.
[Synthesis Example A5: Benzophenone type polymer (solution)]
A UV-absorbing polymer solution (solid content concentration 50%) was obtained in the same manner as in Synthesis Example A1 except that the formulation shown in Table 1 was used.
[Synthesis Example A6: Salicylate type polymer (solution)]
A UV-absorbing polymer solution (solid content concentration 50%) was obtained in the same manner as in Synthesis Example A1 except that the formulation shown in Table 1 was used.
[Synthesis Example A7: Triazine type polymer (solution)]
A UV-absorbing polymer solution (solid content concentration 50%) was obtained in the same manner as in Synthesis Example A1 except that the formulation shown in Table 1 was used.
[Synthesis Example A8: Triazine type polymer (solution)]
A UV-absorbing polymer solution (solid content concentration 50%) was obtained in the same manner as in Synthesis Example A1 except that the formulation shown in Table 1 was used.

  The meanings of the abbreviations in Table 1 are shown below.

(A) -1: 2- [2′-hydroxy-5 ′-(methacryloxyethyl) phenyl] -2H-benzotriazole (a) -2: 2- [2′-hydroxy-5 ′-(2′- Hydroxy-3'-methacryloyloxypropoxy) phenyl] -2H-benzotriazole (a) -3: 2-benzoyl-5- (2'-methacryloyloxyethyl) -phenol (a) -4: phenyl-3- (2 -Hydroxy-3-methacryloyloxypropyl) salicylate (a) -5: 2,4-bis (2,4-dimethylphenyl) -6- [2-hydroxy-4- (2-methacryloyloxyethoxy, 2-dode) Siloxymethyl)]-1,3,5-triazine MMA: methyl methacrylate AA: acrylic acid MAA: methacrylic acid HEMA: hydroxymethacrylate Le BA: butyl acrylate EA: ethyl acrylate MPTMS: 3- methacryloxypropyl trimethoxysilane polymerization initiator: 2,2'-azobis (2,4-dimethylvaleronitrile)

[Synthesis Example A9: (aqueous dispersion)]
While stirring a TEA aqueous solution composed of 2.9 g of triethylamine (TEA) (equivalent to the carboxyl group of the UV absorbing polymer) and 113.8 g of ion-exchanged water in 100 g of the UV absorbing polymer solution obtained in Synthesis Example A1. Small portions were added. After the reaction system became uniform, MEK was removed by vacuum degassing to obtain an aqueous dispersion (solid content concentration 30%) of a transparent ultraviolet absorbing polymer.
[Synthesis Examples A10 to A16 (aqueous dispersion)]
The UV-absorbing polymer was the same as Synthesis Example A9 described above except that the UV-absorbing polymer solution obtained in Synthesis Examples A2 to A8 was used in place of the UV-absorbing polymer solution obtained in Synthesis Example A1. An aqueous dispersion (solid content concentration 30%) was obtained. All the aqueous dispersions were slightly blue to transparent.

(2) <Synthesis of polyurethane (B)>
[Synthesis Example B1: Dispersion of Polyurethane (B1)]
A reaction vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen blowing tube, and a manhole was prepared. After replacing the inside of the reaction vessel with nitrogen gas, 6.0 g of dimethylolpropionic acid (DMPA), polyhexamethylene carbonate diol (trade name “Placcel CD220”, manufactured by Daicel Chemical Industries, Ltd., number average molecular weight determined by terminal functional group determination 2000) 100 g and MEK 59.0 g were charged. Next, 31.9 g of hexamethylene diisocyanate (HDI) (NCO group is twice equivalent to OH group) is added, and the reaction is carried out at 90 ° C. until the NCO group of the resin reaches 4.0% of the theoretical value. A prepolymer solution was obtained. After the obtained urethane prepolymer solution was cooled to 40 ° C., 4.5 g of TEA was added. Furthermore, 317.3 g of ion-exchanged water was added, and the mixture was stirred and emulsified until the inside of the system became uniform, thereby obtaining a urethane prepolymer aqueous dispersion. A solution obtained by diluting 15.3 g of isophorone diamine (IPDA) with 35.7 g of ion-exchanged water was added dropwise to the obtained urethane prepolymer aqueous dispersion to react with the NCO group of the urethane prepolymer. The mixture was stirred until 2,270 cm ⁻¹ absorption due to free isocyanate groups disappeared as determined by infrared absorption spectrum analysis. Next, MEK was removed by vacuum degassing to obtain a dispersion of polyurethane (B1) having an acid value of 16.4 mgKOH / g (solid content concentration 30%).

(3) <Manufacture of polymer composition>
A polymer composition was produced according to “Production Method 1”, “Production Method 2”, or “Production Method 3” shown below. In the examples, the “polymer composition” is a main component for forming a coating film of a paint and substantially exhibits the performance of the paint.

“Production Method 1”: A solution or an aqueous dispersion of a separately synthesized ultraviolet absorbing polymer (A) and a dispersion of polyurethane (B) are mixed.
“Manufacturing method 2”: After the polyurethane (B) prepolymer was prepared, a solution of the ultraviolet absorbing polymer (A) was added and uniformly dispersed in water, and then a urethane chain elongation reaction was performed.
“Manufacturing method 3”: A polyurethane (B) prepolymer is prepared and dispersed in water, and then an aqueous dispersion of the ultraviolet absorbing polymer (A) is added, followed by urethane chain elongation reaction.

[Example 1: Polymer composition (Production method 1)]
To 100 g of the dispersion of polyurethane (B1), 4.1 g of the aqueous dispersion of the ultraviolet absorbing polymer obtained in Synthesis Example A9 was added little by little with stirring to obtain a polymer composition (Example 1). The obtained polymer composition was almost transparent, and no precipitates were generated. Moreover, the solid content concentration of the obtained polymer composition is 30%, the acid value of the solid content (resin component) is 17.0 mg KOH / g, and the proportion of the structural unit derived from the compound (a) contained in the solid content ( Compound (a) content ratio) was 2%.

[Examples 2 to 8: Polymer composition (Production method 1)]
In place of the aqueous dispersion of the ultraviolet absorbing polymer obtained in Synthesis Example A9, the aqueous dispersion of the ultraviolet absorbing polymer obtained in Synthetic Examples A10 to A16 was used in the same manner as in Example 1 described above. Polymer compositions (Examples 2 to 8) were obtained. All the polymer compositions were almost transparent, and no precipitates were generated. Table 2 shows the properties of the obtained paint.

[Example 9: Polymer composition (Production method 2)]
A reaction vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen blowing tube, and a manhole was prepared. After replacing the inside of the reaction vessel with nitrogen gas, 10.0 g of DMPA, 100 g of polyhexamethylene carbonate diol (Placcel CD220), and 70.9 g of MEK were charged. Next, 55.3 g of isophorone diisocyanate (IPDI) (2 times equivalent of NCO group to OH group) was added, and the reaction was carried out at 90 ° C. until the NCO group of the resin reached 4.4% of the theoretical value. A polymer solution was obtained. After the obtained urethane prepolymer solution was cooled to 40 ° C., 15.2 g of the ultraviolet absorbing polymer solution obtained in Synthesis Example A1 was added. Further, 8.0 g of TEA was added, and 395.4 g of ion-exchanged water was added, and the mixture was stirred and emulsified until the inside of the system became uniform to obtain a urethane prepolymer aqueous dispersion. A solution obtained by diluting 20.1 g of IPDA with 46.9 g of ion-exchanged water was added dropwise to the obtained urethane prepolymer aqueous dispersion to react with the NCO group of the urethane prepolymer. The mixture was stirred until 2,270 cm ⁻¹ absorption due to free isocyanate groups disappeared as determined by infrared absorption spectrum analysis. Subsequently, MEK was removed by vacuum degassing to obtain a polymer composition (Example 9). The polymer composition obtained had a solid content concentration of 30%, an acid value of the solid content (resin component) of 23.0 mgKOH / g, and a compound (a) content of 2%. In addition, let the polyurethane contained in the obtained polymer composition be "polyurethane (B2)."

[Examples 10 to 16: Polymer composition (Production method 2)]
A polymer composition (in the same manner as in Example 9 described above) except that the ultraviolet absorbing polymer solution obtained in Synthesis Examples A2 to A8 was used instead of the ultraviolet absorbing polymer solution obtained in Synthesis Example A1. Examples 10 to 16) were obtained. Properties of the obtained polymer composition are shown in Table 2.

[Example 17: Polymer composition (Production method 3)]
A reaction vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen blowing tube, and a manhole was prepared. After replacing the inside of the reaction vessel with nitrogen gas, 12.0 g of DMPA, 100 g of polyhexamethylene carbonate diol (Placcel CD220), and 79.4 g of MEK were charged. Next, 73.2 g of hydrogenated MDI (HMDI) (2 times equivalent of NCO group to OH group) was added, and the reaction was carried out at 90 ° C. until the NCO group of the resin reached 4.4% of the theoretical value. A prepolymer solution was obtained. After cooling the obtained urethane prepolymer solution to 40 ° C., an aqueous solution in which 9.1 g of TEA is dissolved in 423.0 g of ion-exchanged water is added, and the urethane prepolymer solution is stirred and emulsified until the inside of the system becomes uniform. A polymer aqueous dispersion was obtained. To the obtained urethane prepolymer aqueous dispersion, 28.3 g of the aqueous dispersion of the ultraviolet absorbing polymer obtained in Synthesis Example A9 was added. Further, a solution obtained by diluting 22.5 g of IPDA with 52.5 g of water was dropped to react with the NCO group of the urethane prepolymer. The mixture was stirred until 2,270 cm ⁻¹ absorption due to free isocyanate groups disappeared as determined by infrared absorption spectrum analysis. Subsequently, MEK was removed by vacuum degassing to obtain a polymer composition (Example 17). The polymer composition obtained had a solid content concentration of 30%, an acid value of the solid content (resin) of 24.5 mgKOH / g, and a compound (a) content of 2%. In addition, let the polyurethane contained in the obtained polymer composition be "polyurethane (B3)."

[Examples 18 to 24: Polymer composition (Production method 3)]
Instead of the aqueous dispersion of the ultraviolet absorbing polymer obtained in Synthesis Example A9, the aqueous dispersion of the ultraviolet absorbing polymer obtained in Synthetic Examples A10 to A16 was used in the same manner as in Example 17 described above. Polymer compositions (Examples 18 to 24) were obtained. Properties of the obtained polymer composition are shown in Table 2.

[Comparative Example 1: Blending of polymeric UV absorber]
To 100 g of the dispersion of polyurethane (B1) obtained in Synthesis Example B1, 3.1 g of a polymeric ultraviolet absorber (trade name “ULS-1700”, manufactured by Otsuka Kogyo Co., Ltd., benzotriazole-based nonionic water emulsion), In addition, 1.0 g of ion-exchanged water was added to obtain a polymer composition (Comparative Example 1) containing a polymeric ultraviolet absorber. The solid content concentration of the obtained coating material was 30%.

[Comparative Example 2: Blending of low molecular weight UV absorber]
3.1 g of 2- (2H-benzotriazol-2-yl) -4 ′, 6-di-tert-pentylphenol (trade name “Tinuvin 328”, manufactured by BASF) was added to the urethane prepolymer solution. Except for the above, a coating material (Comparative Example 2) containing a low molecular weight UV absorber was obtained in the same manner as in Synthesis Example B1. The polymer composition obtained had a solid content concentration of 30% and an acid value of the solid content (resin) of 16.4 mgKOH / g.

[Comparative Example 3: UV-absorbing polymer aqueous dispersion]
The aqueous dispersion (solid content concentration of 30%) of the UV-absorbing polymer obtained in Synthesis Example A9 is referred to as “polymer composition of Comparative Example 3”.

(4) <Test example>
[Test 1: Film properties]
Each of the polymer compositions of Examples 1 to 24 and Comparative Examples 1 to 3 was coated on a PET film and then dried by heating to obtain a coating film having a coating film having a thickness of 20 μm.

  When the polymer compositions of Examples 1 to 24 were used, transparent and good films could be obtained. In particular, when the polymer compositions of Examples 9 to 24 were used, the formed coating film had high gloss. On the other hand, the coating film formed using the polymer compositions of Comparative Examples 1 and 2 was cloudy. Moreover, the crack formed in the coating film formed using the polymer composition of the comparative example 3, and a part of coating film peeled from PET film. Since the polymer compositions of Comparative Examples 1 and 2 have poor compatibility, it is considered that the formed coating film was clouded. Moreover, since the polymer composition of Comparative Example 3 contains only an acrylic resin having a high glass transition point (Tg) as a resin component, it is considered that the film formability and adhesion are not good. Table 3 shows the evaluation results of the appearance of the obtained film.

<Evaluation criteria for film appearance>
◎: Transparent high gloss coating ○: Transparent coating ×: Cloudy coating ××: Cracks and peeling on coating

[Test 2: UV absorption function]
Each of the polymer composition of Example 1 and the polyurethane (B1) dispersion obtained in Synthesis Example B1 was coated on a release paper and then dried by heating to obtain a film having a thickness of 20 μm. The ultraviolet absorption spectrum of the obtained film was measured using an ultraviolet-visible spectrophotometer (Ubest V-550) manufactured by JASCO Corporation. The measured ultraviolet absorption spectrum is shown in FIG. As shown in FIG. 1, it is apparent that the polymer composition of Example 1 can form a film having a sufficient ultraviolet absorption function.

[Test 3: Infrared absorption function]
The polymer composition of Example 1 was coated on a release paper and then dried by heating to obtain a film having a thickness of 10 μm. The infrared absorption spectrum of the obtained film was measured using a Fourier transform infrared spectrophotometer (FT / IR-350) manufactured by JASCO Corporation. The measured infrared absorption spectrum is shown in FIG.

[Test 4: Water resistance and solvent resistance (Examples 25 to 31, Comparative Examples 1 and 2)]
With respect to the polymer compositions of Example 1 and Example 8, various crosslinking agents were blended according to the blending shown in Table 4 (Examples 25 to 31).

  The polymer compositions of Examples 25 to 31 and the polymer compositions of Comparative Examples 1 and 2 were each coated on an easy-adhesion-treated PET film and then dried at 100 ° C. for 5 minutes to form a coating film having a thickness of 20 μm. (Film) was formed. The formed coating film was aged at 50 ° C. for 3 days, then immersed in deionized water and toluene for 1 hour at room temperature, and then pulled up to observe the state of the coating film. In addition, the coating film immersed in deionized water was used for water resistance evaluation. Moreover, the coating film immersed in toluene was used for evaluation of solvent resistance. Table 5 shows the evaluation results of water resistance and solvent resistance.

  Regarding water resistance, the coating films formed using the polymer compositions of Examples 25 to 31 were not changed in appearance and remained transparent. On the other hand, both of the coating films formed using the polymer compositions of Comparative Examples 1 and 2 were further whitened.

  Regarding solvent resistance, the coating films formed using the polymer compositions of Examples 26 to 30 containing a crosslinking agent were not changed in appearance and remained transparent. On the other hand, the coating films formed using the polymer compositions of Examples 22 and 31 and the polymer compositions of Comparative Examples 1 and 2 that did not contain a crosslinking agent were both swollen.

[Test 5: Non-bleed out property]
A coating film (film) formed in the same manner as in the above “Test 4” was allowed to stand at room temperature, and the change with time was observed. Table 5 shows the evaluation results of the non-bleed-out property.

  Regarding the coating films formed using the polymer compositions of Examples 25 to 31 and Comparative Example 1, the appearance was not changed and remained transparent (however, the polymer composition of Comparative Example 1 was used). The coating film formed was cloudy at the initial stage). On the other hand, about the coating film formed using the polymer composition of the comparative example 2, the low molecular weight ultraviolet absorber bleeded out and it became the external appearance which wiped white powder.

[Test 6: Light resistance test]
A coating film (film) formed in the same manner as in the above-mentioned “Test 4” was subjected to a light resistance acceleration test using a xenon weatherometer, and the appearance change of the paint was confirmed. The test conditions were as follows: temperature 89 ± 3 ° C., humidity 50 ± 5%, illuminance 50 to 150 w / m ² , 300 to 400 nm, irradiation energy 80 MJ or 125 MJ. Table 5 shows the results of the light resistance test.

  About the coating film formed using the polymer composition of Examples 22-27 and Comparative Example 1, neither 80MJ nor 125MJ changed color (however, it was formed using the polymer composition of Comparative Example 1). The coated film was cloudy at the initial stage). On the other hand, regarding the coating film formed using the polymer composition of Comparative Example 2, both 80 MJ and 125 MJ turned yellow.

[Test 7: Adhesion to substrate]
Regarding adhesion to the substrate, Examples 22 to 27 were applied to a PET film, a polyvinyl chloride sheet, an olefinic thermoplastic (TPO) film subjected to a corona discharge treatment, an acrylic sheet, a galvalume steel plate, and a glass plate. A coating film was formed using the polymer composition, and a peeling test using a cellophane tape was conducted according to JISK5600-5-6. Table 5 shows the adhesion evaluation results.

  About the coating film formed using Examples 25-31 and the polymer composition of Comparative Examples 1 and 2, the adhesion property of the PET film, the vinyl chloride sheet, the olefin-based thermoplastic (TPO) film, and the acrylic sheet subjected to the easy adhesion treatment is It was good. The Galvalume steel plate and glass plate had good adhesion in Example 31 due to the effect of silanol.

<Evaluation criteria for water resistance, solvent resistance, and non-bleed out>
Water resistance ○: No change, △: White turbidity, X: Vigorous whitening Solvent resistance ◎ No change, ○: Swelling Non-bleed out ○ ○: No change, ×: Bleed out Light resistance ○: No discoloration, ×: Discoloration Existence Adhesiveness: 95/100 to 100/100, ○: 80/100 to 94/100
Δ: 50/100 to 79/100, x: 0/100 to 49/100
From the above, if the coating material of the example containing the self-emulsifying type polymer ultraviolet absorber (ultraviolet absorbing polymer) and the polyurethane (B) dispersion is used, a coating film excellent in water resistance and non-bleed out property is formed. Clearly it is possible. Furthermore, the coating film excellent also in solvent resistance can be formed by adding a crosslinking agent. On the other hand, in the coating material of Comparative Example 1 to which the polymeric ultraviolet absorbent dispersed in water using an emulsifier was added, the water resistance of the formed coating film was insufficient. In addition, in the polymer composition of Comparative Example 2 to which the low molecular weight UV absorber was added, bleed-out of the low molecular weight UV absorber over time was observed. Moreover, the adhesiveness with respect to the base material of a plastic sheet, a metal, and glass was favorable.

  ADVANTAGE OF THE INVENTION According to this invention, while being excellent in compatibility, water resistance, and non-bleed out property, the coating material which can form the coating film which has a high ultraviolet absorption function can be obtained. This paint is excellent in weather resistance and durability, alone or in combination with various resins, and is used for building interior and exterior materials, base materials constituting solar cells, vehicle interior and exterior materials, marking films, furniture, and electrical products. Useful as a paint. Also, it has good adhesion and is useful as a coating material for all substrates such as plastic sheet, various films, plastic molding, rubber molding, cloth, paper, wood, glass and metal. It is also useful as a primer coating because of its adhesion to the substrate.

Claims (13)

A paint comprising a polymer composition comprising an ultraviolet absorbing polymer (A) and a dispersion of polyurethane (B),
The ultraviolet-absorbing polymer (A) has a carboxyl group obtained by polymerizing a polymerization component comprising a compound (a) having a double bond and an ultraviolet absorbing group and a double bond-containing component (h). A polymerization product having
The polyurethane (B) comprises a compound (b) having an active hydrogen-containing group and an anionic hydrophilic group (excluding a hydroxyl group), a polyol (c) and / or a polyamine (d), and a polyisocyanate (e). It is a reaction product obtained by reacting the contained reaction components,
The acid value of the ultraviolet absorbing polymer (A) is 2 to 200 mgKOH / g,
Wherein contained in the ultraviolet absorptive polymer (A), Ri ratio 30 to 80% by mass of structural units derived from a compound having a double bond and ultraviolet absorbing group (a),
The ultraviolet absorptive polymer (A) is, paint characterized by neutralizing salts der Rukoto. The paint according to claim 1, wherein the compound (a) having the double bond and the ultraviolet absorbing group is represented by any one of the following general formulas (1) to (4).
(In the general formula (1), X represents a halogen, a hydrogen atom, or an alkyl group having 10 or less carbon atoms, R ₁ represents a hydrogen atom or an alkyl group having 10 or less carbon atoms, and R ₂ represents a single atom. A bond, an alkylene group having 10 or less carbon atoms, an oxyalkylene group having 10 or less carbon atoms, or a hydroxyalkanediyloxy group having 10 or less carbon atoms, and R ₃ represents a hydrogen atom or a methyl group.
(In the general formula (2), X represents a halogen, a hydrogen atom, or an alkyl group having 10 or less carbon atoms, and R ₁ is a single bond, an alkylene group having 10 or less carbon atoms, or an oxyalkylene having 10 or less carbon atoms. Group or a hydroxyalkanediyloxy group having 10 or less carbon atoms, and R ₂ represents a hydrogen atom or a methyl group.)
(In the general formula (3), X represents a halogen, a hydrogen atom, or an alkyl group having 10 or less carbon atoms, and R ₁ is a single bond, an alkylene group having 10 or less carbon atoms, or an oxyalkylene having 10 or less carbon atoms. Group or a hydroxyalkanediyloxy group having 10 or less carbon atoms, and R ₂ represents a hydrogen atom or a methyl group.)
(In the general formula (4), R ₁ represents a single bond, an alkylene group having 20 or less carbon atoms, an oxyalkylene group having 20 or less carbon atoms, or a hydroxyalkanediyloxy group having 20 or less carbon atoms, and R ₂ represents A hydrogen atom or a methyl group, and R _{3 to} R ₆ each independently represents a hydrogen atom, an alkyl group, or an alkoxyl group.)   The double bond-containing component (h) is at least one monomer selected from the group consisting of styrene monomers, acrylic monomers, methacrylic monomers, and acrylonitrile monomers, and acrylic acid or methacrylic acid. The paint according to claim 1, which is contained at least.   The ultraviolet absorbing polymer (A) has a glass transition point (Tg) of -20 to 160 ° C. and a weight average molecular weight (Mw) of 1,000 to 1,500,000, and can be dissolved or dispersed in water. The paint according to claim 1, which is a polymer.   The paint according to claim 1, wherein a content ratio of the ultraviolet absorbing polymer (A) is 0.1 to 50% by mass on the basis of the total solid content. The reaction component for preparing the polyurethane (B) further comprises an aliphatic, aromatic or alicyclic hydrocarbon diol having a number average molecular weight of less than 500 and an alkylene oxide adduct thereof, and a dialkanol having 18 or less carbon atoms. At least one short-chain diol component (f) selected from the group consisting of amines and / or aliphatic, aromatic or alicyclic hydrocarbon diamines having 13 or less carbon atoms and aliphatic or aromatic carbonizations having 10 or less carbon atoms The paint according to claim 1, comprising at least one short-chain diamine component (g) selected from the group consisting of hydrogen dihydrazide . The polyurethane (B) is
Compound (b) having active hydrogen-containing group and anionic hydrophilic group (excluding hydroxyl group), polyol (c), polyamine (d), short-chain diol component (f), and short-chain diamine Total active hydrogen-containing groups (excluding anionic hydrophilic groups) of component (g) (1);
The paint according to claim 1, which is a reaction product obtained by reacting the isocyanate group (2) of the polyisocyanate (e) with an equivalent ratio of (1) / (2) = 0.9 to 1.5. . The paint according to claim 1 or 7, wherein the compound (b) having the active hydrogen-containing group and the anionic hydrophilic group (excluding the hydroxyl group) is a compound represented by the following general formula (5).
(HO-R '-) _2- R-R "-X (5)
(In the general formula (5), R represents a trivalent aliphatic hydrocarbon group or a tertiary amine structure, R ′ represents an alkylene group, R ″ represents a single bond or an alkylene group, X shows -COOH, -SO ₃ H, or -PO ₃ H _2.)   The paint according to claim 1, 7 or 8, wherein the compound (b) having the active hydrogen-containing group and the anionic hydrophilic group (excluding the hydroxyl group) is dimethylolalkanoic acid.   The paint according to claim 1 or 7, wherein the polyurethane (B) has a weight average molecular weight of 1,000 to 500,000.   It is a coating material as described in any one of Claims 1-10, Comprising: Furthermore, at least selected from the group which consists of an epoxy compound, a carbodiimide compound, an aziridine compound, an oxazoline compound, and an isocyanate compound (a block body is included). A paint comprising one kind of cross-linking agent. It is a manufacturing method of the paint according to any one of claims 1 to 11,
The manufacturing method characterized by including the process of mixing the solution or aqueous dispersion of the said ultraviolet absorption type polymer (A), and the dispersion of the said polyurethane (B). It is a manufacturing method of the coating material which concerns on Claims 1-11, Comprising: In the intermediate | middle step of the process of preparing the dispersion of the said polyurethane (B), the solution or water of the said ultraviolet absorption type polymer (A) is used for the produced | generated urethane prepolymer. The manufacturing method of the coating material characterized by including the process of adding a dispersion.