JP3175144B2 - Resin composition for primer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a primer resin used for protection or cosmetic purposes such as polyolefin resins, for example, polypropylene, polyethylene, ethylene propylene copolymer, ethylene propylene diene copolymer and the like. The present invention relates to a resin composition for a primer for coating a sheet, a film, and a molded article with a paint, or for bonding a film, a cloth, or the like.

[0002]

2. Description of the Related Art In recent years, plastics have many advantages such as high productivity, wide design freedom, light weight, rust prevention and impact resistance. It is often used as a material for such applications.
In particular, polyolefin resin is inexpensive and moldable,
It has many excellent properties such as chemical resistance, heat resistance, water resistance, and good electrical properties, and is widely used as an industrial material. It is one of the materials whose demand is expected to grow in the future. is there. However, polyolefin resins are different from polar synthetic resins, such as polyurethane resins, polyamide resins, acrylic resins, and polyester resins, in that they are non-polar and crystalline, and are difficult to paint and adhere. Having.

[0003] For coating and bonding of such a hardly adherent polyolefin resin, a low chlorinated polyolefin having a strong adhesive force to the polyolefin resin has been conventionally used as a binder resin. For example, JP
-36128, JP-B-63-50381, JP-A-59-16653
No. 4, JP-B-63-36624 and the like, the content of chlorine containing carboxylic acid or carboxylic anhydride is 5 to 50%.
Low chlorinated polypropylene or low chlorinated propylene
An α-olefin copolymer has been proposed as a primer for coating a polyolefin-based molded product or a binder resin for coating. In order to attach such a composition to a polyolefin-based resin, it was necessary to previously clean the base material surface with a vapor of a chlorine-based solvent such as 1,1,1-trichloroethane or tricrene. However, since the chlorine-based solvent causes air pollution and destruction of the ozone layer, recently, the base material is often washed with water or not washed at all.

As styrene-conjugated diene block copolymers that can be used without washing with a chlorine-based solvent,
Compositions comprising a modified copolymer obtained by graft copolymerization of an α, β-unsaturated vinyl monomer having a hydroxyl group or a composition obtained by further chlorinating the modified copolymer (JP-A-4-248845, JP-A-5-28845) No. -25405), a composition containing a chlorinated styrene-isoprene-block copolymer as an essential component (JP-A-5-25404), and a propylene / ethylene / α-olefin random copolymer. There are compositions (JP-A-5-112750 and JP-A-5-112751) containing a chlorinated product of a graft modified product as an essential component, and these compositions are used as coating primers for polyolefin-based resins or coating resins. In the case of using it, sufficient adhesion cannot be obtained unless the baking temperature after coating is increased.

Further, a composition comprising a chlorinated modified polyolefin obtained by reacting an acid-modified polyolefin with a low molecular weight diol or a low molecular weight compound having a hydroxyl group and an amino group (JP-A-7-247381, JP-A-7-247382
Has disadvantages such as deterioration of quality after long-term storage.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a method for treating a polyolefin resin substrate surface with a chlorine-based solvent vapor such as 1,1,1-trichloroethane or trichlene without using a low baking temperature. Another object of the present invention is to provide a primer resin composition having excellent adhesion.

[0007]

The resin composition for a primer according to the present invention, which solves the above-mentioned problems, comprises (a) a carboxylic acid or a carboxylic anhydride having a content of 1 to 10% by weight and a chlorine content of 5 to 5%. 50% by weight of a carboxyl group-containing chlorinated polyolefin, 100 parts by weight and (b) an ethylene content of 20 to
A resin for a primer comprising 60 mol%, an ethylene-propylene copolymer having a weight average molecular weight of 500 to 5,000 and a viscosity at 0 ° C. of 500 mPa · s to 30,000 mPa · s, 5 to 30 parts by weight, and (c) an organic solvent. A composition.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The carboxyl group-containing chlorinated polyolefin of the component (a) used in the present invention has a property of adhering to both a polyolefin resin and a top coat, and is used in forming a skeleton of the present composition. The component (a), which is an essential binder resin, can be easily produced by using a known method.

For example, the raw material polyolefin is melted by heat,
If necessary, the viscosity is reduced by thermal decomposition, and 1 to 10% by weight of an unsaturated carboxylic acid monomer of carboxylic acid or carboxylic anhydride is graft-polymerized in the batch or continuous manner in the presence of a radical generator, and then water or Dispersed or dissolved in a medium such as carbon tetrachloride or chloroform, and under pressure or normal pressure under a radical generating catalyst or ultraviolet irradiation, 50 to 1
It can be obtained by blowing chlorine gas in a temperature range of 20 ° C. to cause a reaction.

Further, it can also be obtained by preliminarily chlorinating the raw material polyolefin by the above-mentioned method and then graft-copolymerizing a carboxylic acid or a carboxylic anhydride in the presence of a radical generator.

As raw material polyolefin, crystalline polypropylene, amorphous polypropylene, propylene-α-
Olefin copolymers and the like can be used alone or as a mixture of two or more types.However, from the viewpoint of workability and adhesiveness of the primer composition, the weight-average molecular weight is 10,000 to 150,000, and the weight average molecular weight is 10,000 to 150,000. A propylene-α-olefin copolymer containing 50 to 97 mol% of a propylene component is preferable.

Particularly, the crystalline polypropylene preferably has a weight average molecular weight of 10,000 to 150,000. If the weight average molecular weight is lower than 10,000, the adhesion to the polyolefin resin becomes worse, and the weight average molecular weight is 150,00
If it exceeds 0, it is not preferable because the primer does not become fine when coated by air spray or the like, and the aesthetic appearance of the coated surface is impaired.

In the propylene-α-olefin copolymer containing 50 to 97 mol% of a propylene component, the α-olefin unit is, for example, ethylene, 1-butene, 1-pentene,
At least one α-olefin having 2 or 4 to 6 carbon atoms selected from 4-methyl-1-pentene, 3-methyl-1-pentene and 1-hexene is preferred. If the weight average molecular weight is less than 10,000 or the propylene component is less than 50 mol%, the adhesion to the polyolefin resin will be poor, and if the weight average molecular weight exceeds 150,000, the primer will be atomized when applied by air spray etc. Otherwise, the aesthetic appearance of the coated surface is impaired, which is not preferable. If the propylene component exceeds 97 mol%, the crystallinity of the propylene-α-olefin becomes high, and as a result, the solvent solubility of the chlorinated product becomes poor. On the other hand, if the carbon number of the α-olefin of the propylene-α-olefin copolymer exceeds 6, the adhesion to the polypropylene resin becomes poor.

In the present invention, crystalline polypropylene and a propylene-α-olefin copolymer containing 50 to 97 mol% of a propylene component may be used in combination. As the combination at that time, an arbitrary combination may be appropriately selected depending on the type of the target polyolefin-based resin material and the like. For example, it is possible to reduce the amount of crystalline polypropylene for a hard material and to increase the amount of crystalline polypropylene for a soft material.

The chlorine content of the component (a) is 5 to 50% by weight.
If it is less than 5% by weight, the solubility in a solvent will be poor, and if it exceeds 50% by weight, the adhesion to a polyolefin resin will be poor.

Examples of the unsaturated carboxylic acid monomer for introducing a carboxyl group include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, aconitic acid and aconitic anhydride. The graft copolymerization amount is preferably 1 to 10% by weight based on the polyolefin. If it is less than 1%, the adhesion to the top coat is poor, and if it exceeds 10%, the adhesion to the polyolefin resin is poor.

In the present invention, a carboxylic acid and a carboxylic anhydride may be used in combination as the unsaturated carboxylic acid monomer. As the combination, the carboxylic acid and the carboxylic anhydride described above may be arbitrarily combined,
Particularly, a combination of acrylic acid, methacrylic acid, and maleic anhydride is preferable.

Examples of the radical generator used in the graft copolymerization reaction include di-tert-butyl peroxide, tert-butyl hydroperoxide, dicumyl peroxide, benzoyl peroxide, tert-butyl peroxide benzoate, and methyl ethyl ketone peroxide. There are peroxides such as oxide, di-tert-butyl diperphthalate and azonitrile such as azobisisobutyronitrile.

The carboxyl group-containing chlorinated polyolefin of the component (a) used in the present invention is usually used by adding an epoxy compound as a stabilizer. The amount of the stabilizer is preferably 1 to 10% by weight based on the component (a). Examples of epoxy compounds that can be used include bisphenol A and epichlorohydrin condensates of polyhydric alcohols, such as bisphenol glycidyl ether, propylene glycol glycidyl ether, glycerol polyglycidyl ether, and sorbitol polyglycidyl ether.

The ethylene-propylene copolymer (b) used in the present invention has an ethylene content of 20 to 60% by mole, a weight average molecular weight of 500 to 5,000 and a viscosity at 0 ° C. of 50%.
0 mPas or more and 30,000 mPas or less (rotated based on JIS K 7117-2
(Measured with a viscometer) is preferred. 20 ethylene content
If the amount is out of the range of 60 to 60 mol%, the fluidity becomes poor and the effect of the present invention cannot be obtained, which is not preferable. On the other hand, if the weight average molecular weight is less than 500, the cohesiveness of the composition is reduced, and if it exceeds 5,000, the fluidity is deteriorated, which is not preferable. On the other hand, those having a viscosity at 0 ° C. of more than 30,000 mPa · s are inferior in flowability, so that the effects of the present invention cannot be obtained. The ethylene-propylene copolymer has a narrow molecular weight, specifically Mw / Mn (weight-average molecular weight / number) by using a specific polymerization catalyst such as vanadium-based or titanium-based and further adjusting the reaction temperature and the like as appropriate. A copolymer having an average molecular weight of 2 or less can be obtained.

The mixing ratio of the components (a) and (b) of the present invention is such that the amount of the component (b) is 5 per 100 parts by weight of the component (a).
-30 parts by weight are preferred. If the amount of the component (b) is less than 5 parts by weight, the wettability to the polypropylene-based resin is deteriorated, and
If the amount exceeds 0 parts by weight, the cohesiveness of the primer composition is reduced, and the adhesion to the polypropylene resin becomes insufficient.

The composition of the present invention is usually used by dissolving it in an organic solvent (c). The solvent concentration may be appropriately selected depending on the application. However, if the solvent concentration is too high or too low, the coating workability is impaired.
The organic solvent is 50 to 10,000 parts by weight based on 00 parts by weight. As the organic solvent to be used, aromatic solvents such as toluene and xylene are preferable, and ester solvents such as ethyl acetate and butyl acetate; ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone; ethanol, isopropanol and n-butanol. , An aliphatic solvent such as n-hexane and heptane, and a cycloaliphatic solvent such as cyclohexane, methylcyclohexane, and ethylcyclohexane.

The resin composition for a primer of the present invention can be colored and kneaded by adding a pigment and kneading the primer composition. Also, by kneading the conductive pigment, it is possible to perform electrostatic coating of the top coat. As pigments, inorganic pigments such as titanium dioxide, talc, calcium carbonate, barium sulfate, zinc white (zinc oxide), red iron oxide (ferric oxide), and aluminum paste, and organic pigments such as azo and phthalocyanine are used. it can.
The conductive pigments include carbon black, gold, silver,
Powders such as copper, nickel and graphite, and mixtures of these powders with metal oxides such as titanium dioxide can be used.

The primer resin composition of the present invention exhibits well-balanced primer properties by itself. However, if necessary, alkyd resins, acrylic resins, polyacryl polyols, polyester resins, polyester polyols, polyether resins, polyether resins, Ether polyol, polyurethane resin, epoxy resin and the like may be further added and used. Further, other additives such as an ultraviolet absorber, an antioxidant, a pigment settling inhibitor, a thixotropic agent and the like may be added.

[0025]

The present invention is characterized in that a carboxyl group-containing chlorinated polyolefin as the component (a) and an ethylene-propylene copolymer having a viscosity at 0 ° C. of from 500 mPa · s to 30,000 mPa · s of the component (b). By using in combination with, without treating the base surface of the polyolefin resin with the vapor of a chlorine-based solvent such as 1,1,1-trichloroethane or tricrene,
Moreover, it is an object of the present invention to obtain a resin composition for a primer having excellent adhesion even at a low baking temperature.

That is, the carboxyl group-containing chlorinated polyolefin of the component (a) has the property that the higher the baking temperature, the better the wettability with the polyolefin resin and the better the adhesion. Ethylene which has good wettability to polyolefin resins even at low temperatures such as
It is considered that the addition of the propylene copolymer improves the wettability at a low temperature as a whole and improves the adhesion.

[0027]

The present invention will be described below in more detail with reference to examples.

(Production Example 1) 5 kg of crystalline polypropylene having a weight-average molecular weight of 20,000 was placed in a four-necked flask equipped with a stirrer, a dropping port and a condenser for refluxing the monomer, and kept at 160 ° C. It melted completely in the kept hot water bath. The atmosphere in the flask was replaced with nitrogen, and while stirring, 400 g of methacrylic acid and 40 g of di-t-butyl peroxide dissolved in 100 ml of heptane were added from separate dropping ports over 30 minutes. At this time, the inside of the system is 16
After maintaining the temperature at 0 ° C. and continuing the reaction for another 30 minutes, unreacted substances were removed over about 30 minutes while reducing the pressure in the flask with an aspirator. Next, the product was put into a glass-lined reaction vessel, 80 liters of chloroform was added, and the mixture was sufficiently dissolved at 100 ° C. under a pressure of ² kg / cm ^2. The chlorination reaction was performed until the chlorine content reached 20% by weight, and chloroform as the solvent was distilled off with an evaporator.
Toluene substitution was performed to obtain a toluene solution of chlorinated polypropylene containing a carboxyl group having a solid content of 30% by weight.

(Production Example 2) 5 kg of crystalline polypropylene having a weight-average molecular weight of 60,000 was placed in a flask similar to that of Production Example 1, and completely melted in a hot water bath kept at 180 ° C. The atmosphere in the flask was replaced with nitrogen, and while stirring, 200 g of maleic anhydride was added over about 5 minutes. Then, 20 g of dicumyl peroxide was dissolved in 50 ml of heptane and added from the dropping port over about 30 minutes. At this time, the inside of the system was kept at 180 ° C., and after continuing the reaction for further 15 minutes, unreacted substances were removed over about 30 minutes while reducing the pressure inside the flask with an aspirator. Next, this product was chlorinated in the same manner as in Production Example 1 to obtain a toluene solution of a carboxyl group-containing chlorinated polypropylene having a chlorine content of 24% by weight and a solid content of 30% by weight.

Production Example 3 5 kg of a propylene-ethylene copolymer (propylene-α-olefin copolymer) having a weight average molecular weight of 40,000 and a propylene component of 80 mol%
Was placed in a flask similar to that of Production Example 1, and completely melted in a water bath kept constant at 140 ° C. The atmosphere in the flask was replaced with nitrogen, and while stirring, 500 g of acrylic acid and 50 g of di-t-butyl peroxide dissolved in 100 ml of heptane were added from separate dropping ports over 30 minutes. At this time, the inside of the system was kept at 140 ° C., and the reaction was further continued for 1 hour. Then, unreacted substances were removed over about 30 minutes while reducing the pressure in the flask with an aspirator. Next, this product was chlorinated in the same manner as in Production Example 1 to obtain a toluene solution of a carboxyl group-containing chlorinated polyolefin having a chlorine content of 12% by weight and a solid content of 30% by weight.

(Production Example-4) Weight average molecular weight is 100,000
With a propylene component of 68 mol% propylene-butene-
5 kg of ethylene copolymer (propylene-α-olefin copolymer, butene: 25 mol%, ethylene: 7 mol%)
Was placed in a flask similar to that of Production Example 1 and completely melted in a hot water bath maintained at 180 ° C. The inside of the flask was replaced with nitrogen, and 100 g of maleic anhydride was added while stirring.
Over about 5 minutes, then dicumyl peroxide 10
g was dissolved in 50 ml of heptane and added from the dropping port over about 30 minutes. At this time, the inside of the system was kept at 180 ° C.
After the reaction was further continued for 15 minutes, unreacted substances were removed over about 30 minutes while reducing the pressure in the flask with an aspirator. Next, this product was chlorinated in the same manner as in Production Example 1 to obtain a toluene solution of a carboxyl group-containing chlorinated polyolefin having a chlorine content of 18% by weight and a solid content of 30% by weight.

(Production Example-5) Weight average molecular weight is 120,000
5 kg of crystalline polypropylene is charged into a glass-lined reaction vessel, 80 liters of chloroform is added, and the mixture is sufficiently dissolved at 100 ° C. under a pressure of ² kg / cm ^2. Blowing from the bottom, the chlorination reaction was performed until the chlorine content was 32% by weight, and the solvent chloroform was distilled off with an evaporator.
Substitution with toluene was performed to obtain a toluene solution of chlorinated polypropylene having a solid content of 30% by weight. Next, 1 kg of this chlorinated polypropylene was placed in a three-necked flask equipped with a stirrer, a dropping port, and a condenser for refluxing the monomer, the inside of the flask was replaced with nitrogen, and benzoyl peroxide was added while stirring at 90 ° C. 3 g was added and the mixture was stirred for about 30 minutes. Next, 12 g of methacrylic acid was added from the dropping port over about 30 minutes, and after further reacting for 3 hours, the concentration was adjusted. A toluene solution was obtained.

(Production Example-6) 5 kg of a crystalline polypropylene having a weight average molecular weight of 80,000 was subjected to a chlorination reaction in the same manner as in Production Example-5 to obtain a chlorine content of 27% by weight and a solid content of 30% by weight. A toluene solution of chlorinated polypropylene was obtained. Next, 1 kg of this chlorinated polypropylene was placed in a flask similar to that of Production Example-5, the atmosphere in the flask was replaced with nitrogen, and 3 g of benzoyl peroxide was added while stirring at 90 ° C, followed by stirring for about 30 minutes. Next, 24 g of molten maleic anhydride was added from the dropping port over about 30 minutes, and after further reacting for 3 hours, the concentration was adjusted. Carboxyl group-containing chlorinated polypropylene (chlorine content: 24.7% by weight, solid content: 30% by weight) %) In toluene.

(Production Example-7) A weight average molecular weight of 100,000
5 kg of propylene-butene copolymer (propylene-α-olefin copolymer) containing 65 mol% of propylene component
Was subjected to a chlorination reaction in the same manner as in Production Example-5 to obtain a chlorinated polyolefin toluene solution having a chlorine content of 25% by weight and a solid content of 30% by weight. Next, 1 kg of this chlorinated polyolefin was placed in the same flask as in Production Example-5,
The atmosphere in the flask was replaced with nitrogen, and 3 g of benzoyl peroxide was added while stirring at 90 ° C., followed by stirring for about 30 minutes. Next, 18 g of acrylic acid was added from the dropping port over about 30 minutes, and after further reacting for 3 hours, the concentration was adjusted, and the carboxyl group-containing chlorinated polyolefin (chlorine content: 2
(3.3% by weight, solid content: 30% by weight).

(Production Example-8) 5 kg of a propylene-ethylene copolymer (propylene-α-olefin copolymer) having a weight average molecular weight of 80,000 and a propylene component of 95 mol%
Was subjected to a chlorination reaction in the same manner as in Production Example-5 to obtain a chlorinated polyolefin toluene solution having a chlorine content of 35% by weight and a solid content of 30% by weight. Next, 1 kg of this chlorinated polyolefin was placed in the same flask as in Production Example-5,
The atmosphere in the flask was replaced with nitrogen, and 3 g of benzoyl peroxide was added while stirring at 90 ° C., followed by stirring for about 30 minutes. Next, 12 g of molten maleic anhydride was added from the dropping port over about 30 minutes, and after further reacting for 3 hours, the concentration was adjusted, and the carboxyl group-containing chlorinated polyolefin (chlorine content: 33.3% by weight, solid content 30% by weight) %) In toluene.

(Production Example-9) 40 g of acrylic acid and di-
Production example except that 4 g of t-butyl peroxide is added
In exactly the same manner as in Example 3, a toluene solution of a carboxyl group-containing chlorinated polyolefin having a chlorine content of 12% by weight and a solid content of 30% by weight was obtained.

(Production Example-10) Carboxyl group-containing chlorinated polypropylene (chlorine content: 23.2) was prepared in exactly the same manner as in Production Example-6 except that 45 g of maleic anhydride was added.
% By weight, solid content 30% by weight).

(Production Example-11) A solid content of 30 was obtained in the same manner as in Production Example-2 except that the chlorine content was changed to 4% by weight.
A toluene solution of chlorinated polypropylene containing carboxyl groups by weight was prepared. However, the chlorine content was too low to precipitate chlorinated products, and a uniform toluene solution was not obtained, making it impossible to prepare a primer.

(Production Example-12) A carboxyl group-containing chlorinated polyolefin having a chlorine content of 55% by weight and a solid content of 30% by weight was obtained in the same manner as in Production Example-7 except that a toluene solution of the chlorinated polyolefin was obtained. (Chlorine content: 51.4% by weight, solid content: 30% by weight) was obtained.

Table 1 summarizes the contents of the production examples.

[0041]

[Table 1] [Example-1] 100 g of the carboxyl group-containing chlorinated polypropylene obtained in Production Example-1 (chlorine content: 20%, solid content 30% toluene solution, methacrylic acid 5.9%), 50 g of cyclohexane, and Epicoat 828 (as a stabilizer) Epoxy resin, epoxy equivalent: 184 to 194, Shell Chemical Co.)
1.5 g, 3 g of an ethylene-α-olefin copolymer (ethylene content: 50 mol%, propylene content: 50 mol%, weight average molecular weight: 2,000), 15 g of titanium dioxide, and 0.3 g of carbon black were mixed, After dispersing the pigment in a sand mill for 1 hour, use a Ford cup # 4 for 13-1.
The viscosity was adjusted with toluene at 4 seconds / 20 ° C., and spray-coated on a polypropylene plate (TX-933A, manufactured by Mitsubishi Chemical Corporation) washed with water to a film thickness of 10 μm. After several minutes, a top coat (two-component curable urethane paint) is spray-coated so that the film thickness becomes 30 to 40 μm,
After drying at room temperature for 5 minutes, forcible drying was performed at 80 ° C. for 30 minutes, and the film was further allowed to stand at room temperature for 1 day. The composition of the primer is shown in Table-2, and the test results of the coating film are shown in Table-5.

[Examples 2 to 8] Based on the composition table shown in Table 2, primers were prepared in the same manner as in Example 1, and the coating films were tested. Table 5 shows the test results of the coating films.

[Comparative Examples 1 to 8] Based on the formulation shown in Table 3, primers were prepared in the same manner as in Examples,
The coatings were tested. Table 6 shows the test results of the coating films.

[Comparative Examples -9 to 17] Based on the formulation shown in Table 4, primers were prepared in the same manner as in Example 1, and the coating films were tested. Table 7 shows the test results of the coating films.

Coating film test method ○ Adhesion 100 cross-cuts were formed on the coated surface to reach the substrate at 1 mm intervals, and a cellophane adhesive tape was stuck thereon and peeled off in a 180 ° direction to leave the coating. The degree was judged. ○ Gasoline resistance A scratch (marked with a mark) reaching the substrate was put on the coated surface, immersed in gasoline, and determined by the time until the coating film was peeled off. ○ Warm water resistance The coated plate was immersed in warm water of 40 ° C for 240 hours to examine the state of the coating film. Further, a scratch (marked by x) reaching the substrate was put on the coated surface, and a cellophane adhesive tape was adhered thereon, and the film was peeled off in a 180 ° direction to examine the adhesion of the coating film. ○ Humidity Resistance The coating film was left in an atmosphere of 50 ° C. and a relative humidity of 98% for 240 hours, and the state and adhesion of the coating film were examined in the same manner as in the case of warm water resistance.

[0046]

[Table 2]

[0047]

[Table 3]

[0048]

[Table 4]

[0049]

[Table 5]

[0050]

[Table 6]

[0051]

[Table 7]

[0052]

According to the results of Table 5 and Table 6, Example 1 was obtained.
As in Comparative Examples 1 to 8, a resin composition for a primer in which a carboxyl group-containing chlorinated polyolefin and an ethylene-propylene copolymer are combined is a primer composition containing no ethylene-propylene copolymer as in Comparative Examples 1 to 8. As compared with, the primer composition of the present invention has excellent adhesion, gasoline resistance, hot water resistance, and moisture resistance, and exhibits good physical properties even when baked at a relatively low temperature of about 80 ° C. with respect to a polyolefin resin. You can see that. Further, as shown in Comparative Examples 9 to 15 shown in Table-7, those out of the scope of the claims of the present application are inferior in the above physical properties, and it can be seen that the present invention is useful.

Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI C09J 123/28 C09J 123/28 // (C08L 23/28 23:16) (56) References JP-A-6-306227 (JP, A) JP-A-5-117458 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 23/16-23/28 C09D 123/16-123/28 C09J 123/16-123 / 28 C09J 5/02

Claims (4)

(57) [Claims] (1) 100 parts by weight of a carboxyl group-containing chlorinated polyolefin having a carboxylic acid or carboxylic anhydride content of 1 to 10% by weight and a chlorine content of 5 to 50% by weight: (b) ethylene content The amount is 20 to 60 mol%, the weight average molecular weight is 500 to 5,000, and the viscosity at 0 ° C is 500 mPa · s or more.
mPa · s or less ethylene-propylene copolymer, 5 to 30
Parts by weight: and (c) a resin composition for a primer comprising an organic solvent. 2. The weight average molecular weight of the raw material polyolefin is
10,000 to 150,000 crystalline polypropylene, or a weight average molecular weight of 10,000 to 150,000 and a propylene component of 50
The resin composition for a primer according to claim 1, which is a propylene-α-olefin copolymer containing up to 97 mol%, wherein the α-olefin has 2 or 4 to 6 carbon atoms. 3. The carboxyl group-containing chlorinated polyolefin is a carboxyl group-containing chlorinated polyolefin obtained by graft-copolymerizing an unsaturated carboxylic acid or an unsaturated carboxylic anhydride onto a polyolefin and then chlorinating the polyolefin. 3. The resin composition for a primer according to 1 or 2. 4. The carboxyl group-containing chlorinated polyolefin is obtained by chlorinating the polyolefin and then graft copolymerizing an unsaturated carboxylic acid or an unsaturated carboxylic anhydride. 3. The resin composition for a primer according to 1 or 2.