JPH06104801B2 - Coating composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is intended for the purpose of protecting a polyolefin resin, for example, a polypropylene homopolymer, an ethylene-propylene copolymer, an ethylene-propylene-diene copolymer, or the like, or for cosmetics. With respect to the coating composition used, more specifically, an isocyanate compound is blended with a copolymer of a specific (meth) acrylic monomer, chlorinated polybutadiene and chlorinated polyolefin, and a polyolefin resin sheet or film is obtained. The present invention also relates to a coating composition which is applied to a molded product with a one-coat finish to give a coating film excellent in appearance, adhesion, weather resistance, moisture resistance, solvent resistance and the like.

[Conventional technology]

Polyolefin resins have excellent properties such as chemical resistance, ozone resistance, heat resistance, water resistance, and good electrical characteristics, and because they are lightweight and inexpensive, they can be used in household appliances, automobile parts, and other industrial materials. Is widely used as a material, and it is one of the materials most expected to grow in the future. However, despite having such characteristics, in the case of automobile parts, for example, in light of energy saving, various plastics have been used to reduce the weight, and even though the amount of use is increasing year by year, the polyolefin resin Use is limited. One of the causes of the impediment to its versatility is that the polyolefin resin is non-polar and crystalline, which makes it extremely difficult to paint and bond it. Conventionally, the surface of polyolefin-based resin moldings has been improved in adhesion by plasma treatment or gas flame treatment to activate them, but these methods require complicated equipment and require a large amount of equipment and time loss. There is a drawback in that the surface treatment effect varies due to the fact that it is accompanied, the complexity of the shape of the molded product, and the influence of the pigments and additives in the resin. Therefore, various primer compositions such as those found in the polypropylene bumper coating of automobiles have been proposed recently as a method for coating without these pretreatments, but this involves the complexity of a two-coat finish. As the coating composition for one-coat finishing, there are chlorinated polyolefins and cyclized rubbers that have strong adhesion to polyolefin resins,
The weather resistance, moisture resistance, solvent resistance, etc. are inferior and do not show sufficient coating performance. In order to compensate for these drawbacks, attempts have been made to use a mixture of chlorinated polyolefin with an acrylic resin or alkyd resin, etc., which has good paint properties.However, acrylic resin and alkyd resin are not compatible with chlorinated polyolefin. Since the solubility is poor, the gloss of the coating film is lowered, and the appearance is significantly impaired. To improve these drawbacks, a coating composition obtained by copolymerizing an acrylic monomer and a chlorinated polyolefin as seen in JP-A-58-71966, and found in JP-A-59-27968 As described above, a chlorinated polyolefin-modified acrylic graft copolymer obtained by copolymerizing a hydroxyl group-containing acrylic monomer or the like with a chlorinated polyolefin, and a resin composition for coating comprising an isocyanate compound as an essential component, Akira
As shown in 62-95372, in the presence of a chlorinated polyolefin and a liquid rubber, a hydroxyl group-containing acrylic modified chlorinated polyolefin and an isocyanate compound as a main component, which are copolymerized with an acrylic monomer having a hydroxyl group. An adhesive resin composition and the like have been proposed. However, in these compositions, chlorinated polyolefin, liquid rubber, and acrylic resin are essentially incompatible with each other as described above. Therefore, a clear solution cannot be obtained. When the paint resin becomes cloudy or has two layers separated, when it is made into a paint, sufficient pigment dispersion cannot be obtained, the gloss of the coating film is poor, and the storage stability of the paint is poor. Further, when used as an adhesive, sufficient adhesive performance cannot be obtained.

[Problems to be Solved by the Invention]

In order to solve the above problems, the present inventors have developed a uniform and transparent liquid copolymer obtained by copolymerizing an acrylic monomer having a hydroxyl group with a chlorinated polydiene and a chlorinated polyolefin. It has been found that a coating composition in which an isocyanate compound is further added to this copolymer exhibits excellent adhesion to a polyolefin resin and gives a tough and glossy coating film. -184
Proposed already at 34.

However, this method shows sufficient effects for polyolefin resin materials used in home appliances, etc., but is necessary for painted objects used outdoors such as automobiles and motorcycles,
The gasoline resistance under severe conditions was somewhat insufficient.

[Means for Solving the Problems]

Therefore, as a result of further studies, the inventors of the present invention obtained by copolymerizing a specific (meth) acrylic monomer, a specific chlorinated polydiene and a specific chlorinated polyolefin in a limited weight ratio range, It was found that a coating composition obtained by blending an isocyanate compound in the obtained copolymer and curing the composition has further improved gasoline resistance as compared with the previous invention (JP-A-62-18434), and completed the present invention. .

That is, the present invention uses cyclohexyl (meth) acrylate
(Meth) acrylic monomer (I) containing 30 to 95 wt% and hydroxyl group-containing (meth) acrylic monomer in the range of 5 to 40 wt% and chlorinated to a chlorine content in the range of 5 to 50 wt% Chlorinated polybutadiene (II) and chlorine content of 5-50
Chlorinated polyolefin chlorinated in the wt% range (II
I), (I) / (II) / (III) = 30-85 / 5-50 / 5-50
The coating composition is characterized in that a copolymer obtained by copolymerization in a weight ratio of 1 is used as a main binder, and an isocyanate compound is added as a curing agent to the binder.

Cyclohexyl (meth) acrylate used in the present invention is a component for smoothly carrying out the copolymerization reaction and for improving properties such as solvent resistance, weather resistance and hardness of the coating film. It is necessary to contain 30 to 95 wt% in the system monomer (I). When it is 30 wt% or less, when a methacrylate having a short chain alkyl group such as methyl methacrylate is used together, gelation occurs during the copolymerization reaction,
A smooth reaction cannot be performed. Further, when a methacrylate having a long-chain alkyl group such as lauryl methacrylate is used in combination, the copolymerization reaction proceeds smoothly, but the gasoline resistance of the coating film deteriorates. When the content is 95 wt% or more, the amount of the hydrociloyl group-containing (meth) acrylate-based monomer is limited, so that the cross-linking density of the cured coating film due to the crosslinking with the isocyanate compound becomes low and the physical properties of the coating film deteriorate.

That is, the amount of cyclohexyl methacrylate is 30 to 95 wt% in the (meth) acrylic monomer (I) in order to obtain good coating properties in carrying out the copolymerization reaction.
% Must be included.

The (meth) acrylic monomer having a hydroxyl group used in the present invention is a component for chemically urethanizing a isocyanate compound as a curing agent to form a cured coating film. 5 to 5 in the monomer (I)
It is necessary to contain 40% by weight, and it is preferable to mix it so that the hydroxyl group content in the copolymer is in the range of 0.6 to 4.0% by weight (based on solid content). If the hydroxyl group content in the copolymer is 0.6 wt% or less, the physical properties of the coating film such as solvent resistance, weather resistance and hardness will be poor. 4.0w
When it exceeds t%, the solution of the copolymer becomes opaque or the two layers are separated, so that the gloss of the coating film decreases. In addition, the adhesion to the polyolefin resin becomes poor. Examples of the (meth) acrylic monomer having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxyisopropyl (meth) acrylate, and 2-hydroxybutyl (meth). ) Acrylate and (poly) caprolactone-modified (meth) acrylate obtained by esterifying 2-hydroxyethyl (meth) acrylate with caprolactone. Further, a mixture of cyclohexyl (meth) acrylate and a (meth) acrylic monomer other than a hydroxyl group-containing (meth) acrylate monomer may be used. Examples of the (meth) acrylic monomer used at this time include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, and 2 ethylhexyl (meth).
There are acrylate, lauryl (meth) acrylate, glycidyl (meth) acrylate and the like.

The chlorinated polybutadiene (III) used in the present invention is
To give flexibility to the coating film and to obtain a uniform and transparent reaction liquid when the (meth) acrylic monomer (I) is copolymerized with the chlorinated polybutadiene (II) and the chlorinated polyolefin (III). It is an indispensable ingredient. That is,
As seen in 58-71966 and JP-A-59-27968, a copolymer of an acrylic monomer and a chlorinated polyolefin does not form a uniform and transparent solution, but separates and becomes cloudy. By adding and copolymerizing chlorinated polybutadiene (II) as in the present invention, a uniform and transparent solution can be obtained.
It gives a strong and glossy coating. The effect of the presence of the chlorinated polybutadiene is that the chlorinated polybutadiene has an appropriate degree of chlorination, and the chlorinated polyolefin (meth)
It is considered to be derived from the fact that the substance is compatible with any of the acrylic polymers.

The raw material of the chlorinated polybutadiene of the present invention is obtained by using butadiene with a specific catalyst such as anionic polymerization method using metallic sodium or organic sodium catalyst, Ziegler type coordination anionic polymerization method, cationic polymerization method using Friedel-Crafts catalyst, and radical polymerization method. Liquid polybutadiene obtained by solution polymerization by a polymerization method, and includes those having a hydroxyl group or a carboxyl group at the terminal. The number average molecular weight of the liquid polybutadiene is preferably 500 to 10,000, and when the number average molecular weight is copolymerized using chlorinated polybutadiene obtained by chlorinating the liquid polybutadiene having a number less than 500, solvent resistance, moisture resistance, weather resistance, etc. The physical properties of the coating film deteriorate. The number average molecular weight is
When 10,000 or more liquid polybutadiene is used, the viscosity of the copolymer becomes too high or the liquid becomes opaque, so that good coating workability and coating film appearance cannot be obtained.

The chlorine content of the chlorinated polybutadiene is preferably in the range of 5 to 50 wt%. If the chlorine content is too low, the appearance of the coating film may deteriorate and gelation may occur during the copolymerization reaction. If the chlorine content is too high, the compatibility with the chlorinated polyolefin (III) deteriorates, so that a good coating film appearance cannot be obtained and the reactivity with the (meth) acrylic monomer (I) also decreases. .

Chlorination of polybutadiene can be easily carried out by a usual reaction method. For example, liquid polybutadiene is dissolved in a chlorinated solvent such as carbon tetrachloride, and chlorine gas is blown at room temperature to 120 ° C under pressure or atmospheric pressure in the presence of a catalyst or a catalyst or under irradiation of ultraviolet rays. It is done by putting in.

The chlorinated polyolefin (III) used in the present invention is
It is a component for imparting adhesiveness to a polyolefin resin, and it is preferable to use it in a chlorine content range of 5 to 50 wt%. If the chlorine content is too low, the solution state at low temperatures and the appearance of the coating film will deteriorate. If the chlorine content is too high, the adhesion to the polyolefin resin will decrease.

As a raw material of chlorinated polyolefin, crystalline polypropylene, amorphous polypropylene, polybutene-1, polypentene-1, 4-methylpentene-1, low density or high density polyethylene, ethylene-propylene copolymer, ethylene-propylene- There are diene copolymers and the like. In addition, (meth) acrylic acid, maleic acid,
Α, β-unsaturated carboxylic acid such as maleic anhydride, citraconic acid, citraconic acid anhydride, fumaric acid, mesaconic acid, itaconic acid, itaconic acid anhydride, aconitic acid, aconitic acid anhydride and its acid anhydride were introduced, Modified polyolefins can also be used. Examples of the polymerization initiator used in the modification reaction include peroxides such as di-tert-butyl peroxide, dicumyl peroxide and benzoyl peroxide, and azonitriles such as azobisisobutyronitrile.

The polyolefin is an α, β-unsaturated carboxylic acid, or
By modifying with the acid anhydride, the pigment dispersibility of the copolymer is further improved. That is, a modified polyolefin in which the saponification value of the modified polyolefin is modified in the range of 6 to 60 is preferable, and when the saponification value is less than 6, the contribution to the pigment dispersibility becomes poor and the saponification value is 60 or more. After the pigment is dispersed, the paint gels or the adhesion to the polyolefin resin decreases.

The chlorination of polyolefin can be carried out in the same manner as the chlorination of polybutadiene described above, but the chlorination reaction temperature is 50-
The range of 120 ° C is preferable, and it is necessary to chlorinate in the presence of a catalyst or irradiation of ultraviolet rays. Further, the method of oxidizing at least one or two or more selected from air, oxygen and ozone at the same time during chlorine blowing of the polyolefin to oxidize the chlorinated polyolefin is a more uniform and transparent solution of the copolymer. Is an effective means to

The (meth) acrylic monomer (I), chlorinated polybutadiene (II) and chlorinated polyolefin (II) according to the present invention
The copolymerization of I) is carried out by solution polymerization. The solvent to be used is preferably an aromatic hydrocarbon solvent such as toluene or xylene, as well as an ester solvent, a ketone solvent, an alcohol solvent, a chlorine solvent, an aliphatic hydrocarbon solvent,
It is acceptable to use a cycloaliphatic hydrocarbon solvent together.

As the polymerization initiator, benzoyl peroxide, di-te
Peroxides such as rt-butyl peroxide and azonitriles such as azobisisobutyronitrile can be used. Quinones such as hydroquinone may be used as the polymerization terminator.

The copolymerization method is as follows: chlorinated polybutadiene (II) and chlorinated polyolefin (III) are appropriately diluted with a solvent and mixed, a polymerization initiator is added and then heated, and then a (meth) acrylic monomer ( The basic process is to gradually add (I) to the reaction, but (I) and (II) and (III) are mixed in advance, a polymerization initiator is added, and the mixture is heated and reacted. Absent.

The (meth) acrylic monomer (I), chlorinated polybutadiene (II) and chlorinated polyolefin (II) according to the present invention
The blending ratio for copolymerizing I) may be appropriately determined according to the desired surface hardness, abrasion resistance, surface gloss, etc. of the coating film, but if it is too large or too small, it is well balanced. No coating film is obtained. That is, (I) / (II) / (III) = 3
Copolymerization in a weight ratio range of 0 to 85/5 to 50/5 to 50 is preferable.

The amount of isocyanate compound added is (I) and (II)
1 to 2 mol of isocyanate group is suitable for 1 mol of hydroxyl group in the copolymer obtained by copolymerizing (III) and (III).

Examples of the isocyanate compound of the curing agent used in the present invention include diisocyanates such as hexamethylene diisocyanate, tolylene diisocyanate, and isophorone diisocyanate. These diisocyanates are used as buret bodies, isocyanurate bodies, and trimethylolpropane. A method in which an isocyanate derivative such as an adduct is used after being modified is more preferable. In addition, as the curing accelerator, there are organometallic compounds such as zinc octenoate and dibutyltin dilaurate, and zinc naphthenate and cobalt naphthenate which are internal curing agents for the oxidative polymerization type resin. The reaction can be accelerated.

[Work]

The coating composition according to the present invention may be used by coating as it is, or may be used as a paint by adding a solvent, a pigment and other additives. Further, the composition shows a well-balanced coating property by itself, but if necessary, alkyd resin, acrylic resin, acrylic polyol, polyester resin, polyester polyol, polyether resin, polyether polyol, polyurethane resin, It does not matter if a chlorinated polyolefin resin or the like is further added and used.

The coating composition according to the present invention is applied to a polyolefin resin sheet or molded article and dried at room temperature to 150 ° C. to obtain a one-coat cured coating film.
The obtained coating film has excellent adhesion and gives a coating film which is much tougher and glossier than other one-coat finish paints used for the same purpose. Is superior in weather resistance, moisture resistance, water resistance and gasoline resistance to the coating composition already proposed in JP-A-62-18434.

The composition of the present invention is not only a polyolefin resin,
It can be applied to other plastics and substrates such as wood, concrete and metal, and can be used as an undercoat. As the top coating used at this time,
Existing paints such as urethane resin paints, melamine resin paints and alkyd resin paints are suitable.

[Effects of Examples and Invention]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

Prototype Example-1 500 g of Nisso Polybutadiene B-3000 (liquid polybutadiene manufactured by Nippon Soda Co., Ltd., number average molecular weight 3000) was placed in a class-lined reaction kettle, and carbon tetrachloride (8) was added and uniformly dissolved. The air was completely purged with nitrogen gas, and while keeping the temperature at 50 ° C and irradiating with ultraviolet rays, chlorine gas was introduced from the bottom of the reaction vessel. Chlorine content of 30wt%, 35wt% 2
A sample was taken out, carbon tetrachloride was distilled off, and it was replaced with toluene to obtain two types of toluene solutions of chlorinated polybutadiene having a nonvolatile content of 50 wt%.

Prototype Example-2 500 g of isotactic polypropylene having a number average molecular weight of 5,000 was charged into a glass-lined reaction kettle, and 8
Carbon tetrachloride was added and dissolved sufficiently at a temperature of 110 ° C. and a pressure of 2 kg / cm ² , and then chlorine gas was introduced from the bottom of the reaction vessel while irradiating with ultraviolet rays. Two samples having chlorine contents of 27 wt% and 30 wt% were taken out, carbon tetrachloride was distilled off and replaced with toluene to obtain two toluene solutions of chlorinated polypropylene having a nonvolatile content of 30 wt%.

Prototype Example-3 500 g of isotactic polypropylene having a number average molecular weight of 15,000 was charged into a glass-lined reaction kettle, and 8
Carbon tetrachloride was added and dissolved sufficiently at a temperature of 110 ° C. and a pressure of 2 kg / cm ² , and then chlorine gas and air were introduced from the bottom of the reaction vessel while irradiating with ultraviolet rays. A sample having a chlorine content of 30 wt% was taken out, carbon tetrachloride was distilled off and replaced with toluene to obtain a toluene solution of chlorinated polypropylene having a nonvolatile content of 30 wt%.

Prototype Example-4 500 g of maleic anhydride-modified polypropylene having a number average molecular weight of 15,000 and a saponification value of 26 was chlorinated in the same manner as in Prototype Example-2, and a maleic anhydride having a chlorine content of 25 wt% and a nonvolatile content of 30 wt% was used. A toluene solution of acid-modified chlorinated polypropylene was obtained.

Example-1 In a flask equipped with a stirrer, a thermometer and a reflux condenser for refluxing a monomer, the chlorinated polybutadiene (chlorine content 30 wt%, non-volatile content 50 wt%) 100 obtained in Prototype Example-1 was used.
g, Chlorinated polypropylene obtained in Prototype Example-2 (chlorine content
27 wt%, non-volatile content 30 wt%) 500 g, toluene 100 g, and benzoyl peroxide 2.5 g were added, and the mixture was stirred at 85 ° C. for 30 minutes.
Next, cyclohexylmethacrylate 119g, methylmethacrylate 81g, laurylmethacrylate 40g, methacrylic acid
A mixture of 57 g of 3 g, 2-hydroxyethyl acrylate was added in about 3 hours, and a copolymerization reaction was performed for about 8 hours.
250 g of toluene was added to stop the copolymerization reaction. The obtained copolymer was a uniform, transparent and viscous liquid, and the nonvolatile content was 40.1 wt%. Next, 100 g of this copolymer and 26 g of titanium dioxide were pigment-dispersed in a sand mill for 3 hours,
Isocyanate curing agent Desmodur N3390 (made by Bayer, hexamethylene diisocyanate type, isocyanurate body) 8.7g was added, and No.4 Ford cup 13-15
The viscosity was adjusted with toluene so that the temperature was 20 ° C / sec, and the polypropylene plate TX-933A (manufactured by Mitsubishi Petrochemical Co., Ltd.) was spray-painted. After drying at room temperature for about 15 minutes, forced drying at 80 ° C. for 30 minutes and leaving it in the room for 1 week, the coating film was tested. The results are shown in Table-1.

Example-2 Chlorinated polybutadiene (chlorine content of 35
wt%, non-volatile content 50 wt%) 100 g, chlorinated polypropylene obtained in prototype example-2 (chlorine content 30 wt%, non-volatile content 30 wt%)
A copolymerization reaction was carried out according to the reaction method of Example-1, with the compounding ratios of 500 g, toluene 350 g, benzoyl peroxide 2.5 g, cyclohexyl methacrylate 243 g, and 2-hydroxyethyl acrylate 57 g. The obtained copolymer was a uniform, transparent and viscous liquid, and the nonvolatile content was 40.2 wt%. Next, this copolymer 100 g, titanium dioxide 26 g, isocyanate curing agent Desmodur N3390, at a mixing ratio of 8.7 g,
A paint preparation and a coating film test were conducted in the same manner as in Example-1. The results are shown in Table-1.

Example-3 Chlorinated polybutadiene (chlorine content of 35
wt%, non-volatile content 50 wt%) 200 g, chlorinated polypropylene obtained in prototype example-3 (chlorine content 30 wt%, non-volatile content 30 wt%)
500g, Toluene 300g, Benzoyl peroxide 2.5g, Cyclohexyl methacrylate 160g, Ethyl acrylate 25
With a blending ratio of 65 g of g, 2-hydroxyethyl methacrylate,
A copolymerization reaction was carried out according to the reaction method of Example-1. The obtained copolymer was a uniform, transparent and viscous liquid, and the nonvolatile content was 40.3 wt%. Next, 100 g of this copolymer, 26 g of titanium dioxide, isocyanate curing agent desmodul N3
A paint preparation and a coating film test were carried out in the same manner as in Example 1 with a compounding ratio of 390,8.7 g. The results are shown in Table-1.

Example-4 Chlorinated polybutadiene obtained in Prototype Example-1 (chlorine content of 30
wt%, non-volatile content 50 wt%) 300 g, maleic anhydride modified chlorinated polypropylene obtained in prototype example-4 (chlorine content 25 wt
%, Non-volatile content 30 wt%) 500 g, toluene 250 g, benzoyl peroxide 2.5 g, cyclohexyl methacrylate 90 g, methyl methacrylate 45 g, 2-hydroxyethyl methacrylate 65 g, and the copolymerization reaction according to the reaction method of Example-1. went. The obtained copolymer was a uniform, transparent and viscous liquid, and the nonvolatile content was 40.2 wt%.
Next, 100 g of this copolymer, 26 g of titanium dioxide, isocyanate curing agent desmodul Z4370 (manufactured by Bayer, isophorone diisocyanate type, isocyanurate) 14.6 g,
A coating composition was prepared and a coating film was tested in the same manner as in Example 1 with a compounding ratio of 0.08 g of di-n-butyltin dilaurate as a curing accelerator. The results are shown in Table-1.

Comparative Example-1 Chlorinated polypropylene obtained in Prototype Example-2 (chlorine content 27
wt%, non-volatile content 30 wt%) 40 g, acrylic polyol Desmophen A-160 (manufactured by Bayer, hydroxyl content 1.6%, non-volatile content 60 wt%) 47 g were mixed. The mixed varnish was opaque and non-uniform and separated on standing to give two layers. Next, a paint preparation and a coating film test were carried out in the same manner as in Example 1 with a mixing ratio of 26 g of titanium dioxide and 9.6 g of Desmodur N3390, an isocyanate curing agent. The results are shown in Table-1.

Comparative Example-2 Chlorinated polypropylene obtained in Prototype Example-2 (chlorine content 27
wt%, non-volatile content 30 wt%) 500 g, toluene 400 g, benzoyl peroxide 2.5 g, cyclohexyl methacrylate 144 g,
Methyl methacrylate 98g, lauryl methacrylate 48g,
Methacrylic acid 3g, 2-hydroxyethyl acrylate 57g
The copolymerization reaction was carried out according to the reaction method of Example-1 at the compounding ratio of. The obtained copolymer was a non-uniform and opaque viscous liquid, and the non-volatile content was 40.3 wt%. Next, coating materials were prepared and coating films were tested in the same manner as in Example 1 with the compounding proportions of 100 g of this copolymer, 26 g of titanium dioxide, and 8.7 g of isocyanate curing agent Desmodur N3390, 8.7 g. The results are shown in Table-1.

Comparative Example-3 Chlorinated polybutadiene obtained in Prototype Example-1 (chlorine content of 30
wt%, non-volatile content 50 wt%) 100 g, chlorinated polypropylene obtained in prototype example-2 (chlorine content 27 wt%, non-volatile content 30 wt%)
500g, toluene 350g, benzoyl peroxide 2.5g, methyl methacrylate 98g, lauryl methacrylate 145g, 2-
A copolymerization reaction was carried out according to the reaction method of Example-1 with a mixing ratio of 57 g of hydroxyethyl acrylate. The obtained copolymer was a uniform and opaque viscous liquid, and the nonvolatile content was 40.2 wt%. Next, 100 g of this copolymer, 26 g of titanium dioxide, isocyanate curing agent desmodul N3390,8.
A coating composition was prepared and a coating film was tested in the same manner as in Example 1 with a compounding ratio of 7 g. The results are shown in Table-1.

Judgment criteria in the table ◎: Good △: Slightly bad XX: Very bad ○: Almost good ×: Poor Test method ・ Adhesiveness Make 100 crevices that reach the base at 1 mm intervals on the coated surface and then A cellophane adhesive tape was adhered and peeled off in the 180 ° direction, and the degree of remaining coating film was evaluated.

-Accelerated weather resistance A carbon arc type sunshine weather meter was used. The glossiness was measured by 60 ° specular reflection and the whiteness was measured by a hunter.

-Hot water resistance The coated plate was immersed in warm water (pure water) at 40 ° C for 120 hours and 240 hours, and the state of the coating film was examined.

・ Gasoline resistance (rubbing 100 times) Soak cotton in impregnated Nichiseki regular gasoline to coat surface 10
The state of the coating film was examined by rubbing 0 times.

(Dip for 2 hours) A scratch (x mark) reaching the substrate was put on the coated surface, and immersed in Nisseki Regular Gasoline for 2 hours to examine the state of the coating film.

From the results in Table-1, the resin components of Examples-1,2,3,4 and Comparative Example 3 were obtained by copolymerizing a (meth) acrylic monomer with chlorinated polybutadiene and chlorinated polypropylene. Is.
Comparative Example-4 is simply a mixture of acrylic resin and chlorinated polypropylene. Comparative Example-2 is obtained by copolymerizing a (meth) acrylic monomer and chlorinated polypropylene. The results in Table-1 show that the compositions of Examples-1,2,3,4 and Comparative Example-3 are superior in gloss of the coating film and the solution state of the varnish as compared with Comparative Examples-1 and 2. ing. That is, it is understood that chlorinated polybutadiene is a very useful component for obtaining a uniform and transparent copolymer. or,
Examples 1, 2, 3, and 4 contain cyclohexyl (meth) acryl in the (meth) acryl-based monomer component, while Comparative Example 3 does not contain these acrylates. The results in Table-1 show that Examples-1,2,3,4 are superior in gasoline resistance to Comparative Example-3. That is, the present invention is a drawback of the composition already proposed by the present inventors in JP-A-62-18434 by incorporating cyclohexyl (meth) acrylate in a (meth) acrylic monomer component and copolymerizing the same. It can be seen that the gasoline resistance was improved.

Claims (9)

[Claims] 1. A (meth) acrylic monomer (I) containing at least 30 to 95% by weight of cyclohexyl (meth) acrylate and 5 to 40% by weight of a hydroxyl group-containing (meth) acrylic monomer, and containing chlorine. A copolymer obtained by copolymerizing chlorinated polybutadiene (II) chlorinated in the range of 5 to 50 wt% with chlorinated polyolefin (III) chlorinated in the range of chlorine content of 5 to 50 wt%. A coating composition comprising a polymer as a main binder and an isocyanate compound as a curing agent. 2. A (meth) acrylic monomer (I), a chlorinated polybutadiene (II) and a chlorinated polyolefin (III).
The coating composition according to claim 1, wherein (I) / (II) / (III) = 30 to 85/5 to 50/5 to 50 (weight ratio) is copolymerized. 3. The hydroxyl group content of the copolymer obtained by copolymerizing (I), (II) and (III) is 0.6 to 4.0 wt%.
The coating composition according to claim 1 or 2, which is (relative to solid content). 4. A chlorinated polybutadiene having a number average molecular weight of 50.
The coating composition according to any one of claims 1 to 3, which is obtained by chlorinating 0 to 10,000 liquid polybutadiene. 5. A chlorinated polybutadiene having a number average molecular weight of 50.
The coating composition according to any one of claims 1 to 4, which is obtained by chlorinating a liquid polybutadiene having a hydroxyl group and / or a carboxyl group of 0 to 10,000. 6. The coating composition according to any one of claims 1 to 3, wherein the chlorinated polybutadiene is a combination of the chlorinated compound according to claim 4 or claim 5. 7. The chlorinated polyolefin is one or more selected from α, β-unsaturated carboxylic acids or their acid anhydrides, and has a saponification value of 6 to 6.
The coating composition according to any one of claims 1 to 6, which is obtained by modifying it to 60 and then chlorinating it. 8. The coating composition according to claim 1, wherein the chlorinated polyolefin is obtained by oxidizing the polyolefin with air and / or oxygen and / or ozone during the chlorination reaction. object. 9. A (meth) acrylic monomer (I) containing cyclohexyl (meth) acrylate and a hydroxyl group-containing (meth) acrylic monomer, chlorinated polybutadiene (II), and chlorinated polyolefin ( A copolymer obtained by copolymerizing III) as a main binder, and an isocyanate compound as a curing agent added thereto, which is a coating composition having good adhesion to a polyolefin molded article or film. Manufacturing method.