JPH05163458A - Coating and resin composition therefor - Google Patents

Abstract

PURPOSE:To obtain the subject composition, containing a polymer prepared by polymerizing a polymerizable monomer blend of a specific composition in the presence of a chlorinated polyolefinic resin and capable of providing films excellent in adhesion to polyolefinic materials, resistance to gasoline, fats and oils, etc. CONSTITUTION:The objective composition containing a polymer obtained by polymerizing 80-60wt.% polymerizable monomer blend prepared by blending (A) 0.5-1.5wt.% unsaturated organosilane compound expressed by the formula [X is group having copolymerizable double bond; Y is hydrolyzable group or halogen; R is inert monovalent organic group; (n) is the number of bonds in Y and 1-3; (m) is the number of bonds in R and 1 or 2, with the proviso that (m + n) is 3] with (B) a carboxyl group-containing unsaturated monomer in an amount so that the hydroxyl value of the produced polymer may be 10-25 and (C) a hydroxyl group-containing unsaturated monomer in an amount so that the hydroxyl value of the produced polymer may be 5-25 in the presence of 5-10wt.% chlorinated polyolefinic resin having 20-40wt.% chlorine content. Furthermore, e.g. vinyltrimethoxysilane is used as the component (A).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a resin composition for paints and paints. The present invention is particularly applicable to a plastic substrate such as a so-called untreated polyolefin such as a molded article, a sheet and a film that has not been subjected to various surface treatments for imparting paintability, without subjecting it to a primer treatment. The present invention also relates to a resin composition for paint and a paint capable of obtaining a paint film having excellent properties such as adhesion, gasoline resistance, alcohol resistance, oil and fat resistance, and weather resistance.

[0002]

2. Description of the Related Art In automobiles, home appliances, office automation equipment and various other industrial fields, synthetic resins such as polyolefin are widely used in place of metal for the purpose of weight reduction, rust prevention and other purposes. In this case, since the surface of the molded product is usually coated, it is required that the coatability of the surface of the molded product is good. Further, the coating film to be applied is required to have good adhesion, gasoline resistance, oil and fat resistance, weather resistance, alcohol resistance and the like. However, the coating film applied on the surface of the molded product made of plastic such as polyolefin such as polyethylene and polypropylene is
Generally, it is inferior in performance such as adhesion, gasoline resistance, weather resistance and oil and fat resistance. Therefore, in order to improve the coating film performance of a paint applied to a molded article made of a plastic such as polyolefin, many attempts have been conventionally proposed.
For example, there is a method for improving adhesion by subjecting the surface of these molded products to degreasing treatment, chromic acid treatment and the like.
Further, there is a method of applying a chlorinated polyolefin or a polyolefin modified with maleic acid or an anhydride thereof on the surface of the molded product in a solution state or a dispersed state and performing a primer treatment, and then applying a paint having excellent coating film properties. (For example, JP-A-58-83042 and JP-A-58-118)
809, JP-A-59-30830, etc.).

On the other hand, as a coating composition for improving the adhesion of a coating film to a polyolefin molded article and other properties, an epoxy resin, a curing agent for an epoxy resin and a polyolefin or ethylene copolymer having a functional group reactive with an epoxy group are used. A composition comprising a coalescence has been proposed (for example, Japanese Patent Laid-Open No. Sho 5)
6-72053, JP-A-58-101122, etc.). Further, a composition comprising an acrylic resin having a functional group capable of reacting with an isocyanate compound and a chlorinated polyolefin and a composition comprising a chlorinated polyolefin-modified acrylic resin having a functional group capable of reacting with an isocyanate compound have been proposed (for example, Kosho 57-1476
7, JP-A-58-17174, JP-A-59.
-27968 publication). Furthermore, an acrylic-modified chlorinated polyolefin resin composition comprising an acrylic resin and a chlorinated polyolefin has been proposed (for example, JP-A-58).
-183718, JP-A-58-194959, JP-A-59-30830, etc.). A resin composition obtained by polymerizing a monomer containing an unsaturated organic silane compound in the presence of a chlorinated polyolefin has also been proposed (Japanese Patent Laid-Open No. 62-275168).

[0004]

However, the above surface treatment method cannot sufficiently improve the coating performance such as adhesion. Further, in the method of applying the primer treatment, depending on the type of the chlorinated polyolefin and the modified polyolefin, there may be one in which good adhesion is obtained, but the operation of applying the primer is complicated, and many primer treatments are required. There are problems that it takes time and labor, and eventually the coating cost rises. Furthermore, it is hard to say that the above-mentioned epoxy composition and urethane composition have sufficient adhesion to a plastic molded product such as polyolefin.

Further, the above-mentioned known acrylic-modified chlorinated polyolefin composition is affected by the chlorine content and blending amount of the chlorinated polyolefin and the performance is affected by gasoline resistance and oil resistance. Performances such as oiliness and weather resistance decline. Therefore, there is a problem that it is difficult to adjust the performance balance. Further, the one using an organic silane compound has a relatively good performance balance, but has a drawback that the oil and fat resistance, gasoline resistance, etc. are insufficient.

The present invention solves the above-mentioned problems and can be applied directly to the surface of a molded article without surface treatment, and the adhesion of coating film, gasoline resistance, oil and grease resistance, weather resistance, etc. The present invention provides a resin composition for coatings, which can provide a coating film having excellent performance.

[0007]

The present invention has a chlorine content of 2
0-40% by weight of chlorinated polyolefin resin 5-10
In the presence of wt.

[Chemical 2] (In the formula, X is a group having a copolymerizable double bond,
Y is a hydrolyzable group or halogen, R is an inert monovalent organic group, n is an integer of 1 to 3 which is the number of bonds of Y, and m is 0, 1 or 2 which is the number of bonds of R, and m + n Is 0.5 to 1.5% by weight of the unsaturated organic silane compound represented by the formula (3), and the acid value of the polymer to obtain an unsaturated monomer containing a carboxyl group is in the range of 10 to 25. And 80 to 60% by weight of a polymerizable monomer compounded in such an amount that the hydroxyl value of the polymer capable of obtaining an unsaturated monomer containing a hydroxyl group is in the range of 5 to 25. The present invention relates to a resin composition for paints containing a coalescence and a paint containing the composition.

Examples of the chlorinated polyolefin resin used in the present invention include polyethylene resin having a chlorine content of 20 to 40% by weight, polypropylene resin, ethylene-propylene copolymer and the like. When the chlorine content is less than 20% by weight, the compatibility is lowered and separation and the like occur, resulting in poor storage stability, and when it exceeds 40% by weight, the adhesion is lowered. Preferably, it is 25 to 35% by weight.

In the above polymerizable monomer composition, the unsaturated organosilane compound represented by the general formula (I) is 0.5 to
1% by weight is blended. By using the unsaturated organic silane compound, coating film performance, particularly adhesion can be improved. If the unsaturated organosilane compound is less than 0.5% by weight, this improving effect is small, and if it exceeds 1.5% by weight, the hydrolyzable group is hydrolyzed during the polymerization to cause a crosslinking reaction to easily cause gelation. From these characteristics, it is preferably used in an amount of 0.6 to 1% by weight, particularly preferably 0.7 to 0.9% by weight.

X in the general formula (I) is a group having a copolymerizable double bond, and examples thereof include an alkenyl group such as a vinyl group, an allyl group and a butenyl group, a cyclohexenyl group, a cyclopentadienyl group and a cyclohexyl group. Cycloalkenyl groups such as sadienyl groups, unsaturated acyloxyalkyl groups such as γ-methacryloxypropyl group, unsaturated acyloxyalkoxy groups such as γ-methacryloxyethylpropyl ether group,
_{CH 2 = C (CH 3)} COO (CH 2) 2 OCH 2 CH (O
H) CH ₂ O (CH ₃ ) ₃ — and the like. Among these, preferred are unsaturated acyloxyalkyl groups such as γ-methacryloxypropyl group and unsaturated acyloxyalkoxy groups such as γ-methacryloxypropyl ether group. Also,
As the hydrolyzable group of Y in the general formula (I),
An alkoxy group having 1 to 6 carbon atoms, an oximo group having 1 to 14 carbon atoms, etc., preferably an alkoxy group such as a methoxy group, an ethoxy group, a butoxy group, a formyloxy group, an acetoxy group or a propyleneoxy group. such an acyloxy _{group, -ON = C (CH 3)} 2, -ON = C (CH
₃ ) A group that produces a hydroxyl group by hydrolysis such as an oximo group such as C ₂ H ₅ and -ON = C (C ₆ H ₅ ) ₂ , -NHC
H _3, and the like alkyl or arylamino group such as -NHC ₂ H ₅ and NH (C ₆ H _5). The groups Y may be the same or different when n is 2 or 3. The group R is an active monovalent organic group, preferably
A hydrocarbon group having 1 to 18 carbon atoms, for example, an alkyl group such as a methyl, ethyl, propyl, butyl, tetradecyl or octadecyl group, an aryl group such as a phenyl group, a benzyl group or a tolyl group, an aralkyl group or an alkaryl group. Etc.

Examples of the unsaturated organosilane compound represented by the general formula (I) include vinyltrimethoxysilane and
Vinyltriethoxysilane, vinyltri (2-methoxyethoxy) silane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltri (2-methoxyethoxy) silane, γ- Examples include acryloxypropyltriethoxysilane and vinyltrichlorosilane.

The group Y in the unsaturated organic silane compound represented by the general formula (I) is a group having a hydroxyl group or a hydroxyl group by reacting with the water used in the raw material and the polymerization solvent used for hydrolysis or substitution reaction. Therefore, it is considered that the functional groups such as hydroxyl groups undergo a crosslinking reaction during the polymerization reaction and / or when the coating material is dried.

In addition to the unsaturated organosilane compound represented by the general formula (I), the polymerizable monomer mixture contains an unsaturated monomer containing a carboxyl group and an unsaturated monomer containing a hydroxyl group. The unsaturated monomer containing a carboxyl group is calculated and blended so that the resulting polymer has an acid value in the range of 10 to 25. When the acid value is less than 10, the gasoline resistance is lowered, and when the acid value is more than 25, the adhesion is lowered. Preferably, it is blended so that the acid value is 15 to 25. The unsaturated monomer containing a carboxyl group,
Acrylic acid, methacrylic acid, maleic acid, itaconic acid,
Examples include fumaric acid, unsaturated dibasic acids of these acids, and acid anhydrides thereof.

The unsaturated monomer containing a hydroxyl group is calculated and blended so that the hydroxyl value of the resulting polymer is in the range of 5 to 25. When the hydroxyl value is less than 5, the oil and fat resistance is lowered, and when the hydroxyl value is more than 25, the adhesion is lowered. The hydroxyl value is preferably 10 to 20. As the unsaturated monomer containing a hydroxyl group, 2-hydroxyethyl acrylate,
From hydroxyalkyl acrylates such as 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, hydroxyalkyl methacrylates such as 2-hydroxypropyl methacrylate, and polyhydric alcohols such as ethylene glycol, propylene glycol, glycerin and pentane erythet. There are derived monovinyl ester compounds and the like.

The polymerizable monomer composition has the general formula (I)
In addition to the unsaturated organic silane compound represented by, an unsaturated monomer containing a carboxyl group and an unsaturated monomer containing a hydroxyl group, methyl acrylate, ethyl acrylate, butyl acrylate, isobutyl acrylate, 2-acrylic acid acrylate Alkyl acrylates such as ethylhexyl, lauryl acrylate, cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, cyclohexyl methacrylate and other alkyl methacrylates Esters, etc.
Examples include aminoalkyl acrylate, aminoalkyl methacrylate, styrene-based monomers such as styrene, vinyltoluene and α-methylstyrene, vinyl derivatives such as vinyl chloride, vinylidene chloride, vinyl acetate and isopropenyl acetate.

In the present invention, the chlorinated polyolefin and the polymerizable monomer blend are blended so that the weight ratio is 5/95 to 10/90 in the former / the latter. If this weight ratio is less than 5/95, the adhesiveness will decrease. Further, if the weight ratio exceeds 10/90, the gasoline resistance and the oil and fat resistance decrease.

Polymerization of the polymerizable monomer composition in the presence of the chlorinated polyolefin is carried out by a known radical polymerization method, and the method is not particularly limited. For example, solution polymerization is performed at 60 to 130 ° C. In this case, aromatic solvents such as toluene and xylene, ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, and ester solvents such as ethyl acetate and butyl acetate are used as the organic solvent. Further, upon polymerization, organic peroxides such as benzoyl peroxide, dicumyl peroxide and dibutyl peroxide, and azobis compounds such as azobisisobutyronitrile are used as polymerization initiators.

The chlorinated polyolefin-containing polymer thus obtained is dissolved in a suitable organic solvent to obtain a coating resin composition. As the organic solvent, those exemplified as the organic solvent for the above solution polymerization can be used. Furthermore, the resin composition of the present invention can be used as a coating by incorporating an inorganic pigment such as titanium white or carbon black, an organic pigment such as a phthalocyanine-based or azo-based pigment, and other additives.

The coating material according to the present invention can be applied by a method such as spray coating or roll coater coating. The paint according to the present invention can be used as a polyolefin material such as a polyolefin-based molded product, a sheet or a film, or a top coat for a polyolefin base material, an enamel paint, a primer or the like.

[0020]

EXAMPLES Examples of the present invention will be shown below. Hereinafter, parts and% mean parts by weight and% by weight. Examples 1 to 9 and Comparative Examples 1 to 8 The composition (I) shown in Table 1 was placed in a reactor equipped with a mixer and a condenser and heated to 110 ° C. to prepare the composition (II) shown in Table 1. It is allowed to drop for 2 hours and kept warm for 1 hour. Furthermore,
The formulation (III) shown in Table 1 was added dropwise over 30 minutes and kept warm for 2 hours to complete the polymerization, thereby obtaining a polymer. After cooling, toluene was added so that the heating residue was about 40%. Then
Toluene / butyl cellosolve = 95/5 in this polymer
(%) Add mixed solvent, ford cup # 4 12-1
It was adjusted to 3 seconds, spray-coated on a non-modified polypropylene molded plate (trade name; Noblen BC-3B / manufactured by Mitsubishi Petrochemical Co., Ltd.) (coating thickness: about 30 μm), and dried at 60 ° C. for 30 minutes. Further, it was left at 23 ° C. for 24 hours to obtain a coating film test plate.

Using this test plate, the adhesion, gloss, alcohol resistance, gasoline resistance, oil and fat resistance, and weather resistance were tested. The test method is as follows. Adhesion: Measured according to JIS K5400 scoring tape test method. Mitsuzawa; 60 degree specular reflectance is measured. Alcohol resistance and gasoline resistance: A rubbing test was performed with a load of 1 kg, and the evaluation results are shown by the following symbols. ◎: Number of times until the coating film disappears 300 or more ○: Number of times until the coating film disappears 150 to 299 ×; Number of times until the coating film disappears 149 or less Oil and fat resistance: Beef tallow (reagent manufactured by Wako Pure Chemical Industries, Ltd.) ) Is applied and 5
After standing at 0 ° C. for 1 hour, it is further left at room temperature for 48 hours. The pencil hardness at this time is measured. (Measurement of pencil hardness; using Mitsubishi Uni) Weather resistance; Sunshine weather meter Measure gloss retention after 600 hours irradiation. The test results are shown in Table 2.

[0022]

[Table 1]

[0023]

[Table 2]

[0024]

The resin composition for paints and paints of the present invention are
Can be directly applied to the surface of polyolefin-based materials without any surface treatment or primer treatment, and has excellent coating adhesion, gloss, alcohol resistance, gasoline resistance, oil and fat resistance, weather resistance, etc. It is a thing.

Claims (2)

[Claims] 1. In the presence of 5 to 10% by weight of a chlorinated polyolefin resin having a chlorine content of 20 to 40% by weight, the compound represented by the general formula (I): (In the formula, X is a group having a copolymerizable double bond,
Y is a hydrolyzable group or halogen, R is an inert monovalent organic group, n is an integer of 1 to 3 which is the number of bonds of Y, and m is 0, 1 or 2 which is the number of bonds of R, and m + n Is 0.5 to 1.5% by weight of the unsaturated organic silane compound represented by the formula (3), and the acid value of the polymer to obtain an unsaturated monomer containing a carboxyl group is in the range of 10 to 25. , And 80 to 60% by weight of a polymerizable monomer mixture obtained by blending an unsaturated monomer containing a hydroxyl group in an amount such that the hydroxyl value of the polymer is in the range of 5 to 25. A coating resin composition containing a polymer. 2. A paint comprising the resin composition for paint according to claim 1.