JPS62283134A - Primer for plastic material - Google Patents

Abstract

PURPOSE:The titled primer which has improved adhesivity to plastic materials, etc., and forms a coating film having improved impact resistance, water resistance etc., comprising a resin composition consisting of a specific ethylene propylene copolymer and a specific copolymer and a crosslinking agent as main components. CONSTITUTION:(A) A composition which comprises A1: ethylene-propylene copolymer subjected to graft polymerization with maleic acid and having 10-100 Mooney viscosity and A2: a copolymer comprising a radically polymerizable unsaturated monomer mixture containing 2-80wt%, preferably 20-60wt% functional monomer and having <=-10 deg.C glass transition point in a weight ratio of the component A1/A2 of 95/5-40/60, preferably 75/25-65/35 wherein the component A2 is at least partially grafted onto the A1 component is blended with (B) a crosslinking agent (e.g. amino resin). The content of maleic acid in the component A1 is preferably 0.5-10wt%, especially 1-5wt%.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention The present invention has excellent adhesion to plastic members and other coatings, and has excellent properties such as impact resistance, water resistance, weather resistance, and chemical resistance. This invention relates to a primer for plastic parts that forms a good coating film.

In recent years, demand for plastic as an industrial material has increased,
There are a wide variety of types and uses.

For example, in the automobile industry, there is an increasing desire to reduce the weight of car bodies, and bumpers, wheels, etc. are already mostly made of plastic. In addition, there is a lanoator grille, lower apron, spoiler, mudguard, foil cap,
Plastics are now being used in parts that used to be made of metal, such as lamp lids, and this trend can also be seen in home appliances, buildings, toys, equipment parts, etc.

With the shift to plastics, for example, the outer parts of automobiles are required to have the same aesthetic appeal and durability as steel plate parts, so it is natural that these plastic parts are coated with paint. .

However, the surface condition of plastic parts varies greatly depending on the raw material, crystallinity, manufacturing conditions, chemical structure, molding conditions, mold release agent, etc., so when painting plastic parts, it is necessary to It is also necessary to select a paint suitable for the surface condition through trial and error, or to develop a new paint.

In particular, developing new paints will improve productivity,
This is not desirable in terms of sales efficiency, and on the painting line, every time a new paint is developed, it is necessary to establish the optimal painting conditions, modify the coating VC equipment and drying equipment, and save space for storing paint. This is not desirable as it may cause problems.

Additionally, even if the same type of plastic molded product is made by different molding manufacturers, the adhesion of the brimer will vary, which often causes peeling accidents.

Therefore, in view of the further expansion of the field of use and variety of plastics, the inventors of the present invention have found that they have excellent adhesion properties even if the surface condition is different, and also adhere well to the coating film of the pond (for example, intermediate coating or top coating coating). After intensive research into developing a primer for plastics that can form a coating film with excellent impact resistance, water resistance, weather resistance, and chemical resistance, the present invention was completed.

That is, the present invention comprises [AI (,) an ethylene-propylene copolymer graft-polymerized with maleic acid, and (b) a functional monomer with two
From a mixture of monocal polymerizable unsaturated monomers containing ~80%! ! l! consisting of the remaining copolymer, and (
α)/(b) is 9515 to 40/6 based on the weight ratio
0, and relates to a plastic brimer comprising as main components a resin composition in which at least a part of the component (b) is graft-polymerized to the component (a), and [B] a crosslinking agent.

Regarding the primer coating film of the present invention, the ethylene-propylene copolymer contained in component (a) is rich in rubber elasticity,
Because it has a high elongation rate and excellent flexibility, it is recommended to pre-coat relatively hard plastic materials such as polyamide resins and nonyl resins to increase the strength of the top coat.
It is very useful for improving impact resistance, bending resistance, etc.

Furthermore, by graft polymerizing maleic acid to this copolymer, it was possible to significantly improve the adhesion with various types of plastics and various coatings such as intermediate coats and top coats. In terms of Vf, the brimer is non-polar and has a low surface energy, and has excellent adhesion to polypropylene plastics, which have poor adhesion to paint films.

Additionally, if the topcoat film is hard, impact stress will concentrate on minute scratches that occur on the topcoat surface, which will grow into cracks, which will spread from the topcoat layer to the lower layers, and eventually Plastics to be coated may be destroyed, but if this plastic is coated with the primer in advance, the rubber elasticity of component (a) itself will absorb the impact energy and protect the plastic from destruction. can.

Furthermore, (b) 1.1! By grafting , component (b), in addition to imparting the excellent weather resistance of component (b) itself, functional groups such as hydroxyl groups can be easily introduced, improving adhesion to plastic materials, It is possible to improve the interlayer adhesion with intermediate coatings and top coatings such as amino/curing acrylic paints and amino-curing polyester paints.

In addition, these functional group components can react with various crosslinking agents ([B] acid components such as Ami-Za (fat), so the primer coating can be crosslinked under appropriate heating and drying conditions. As a result, it is not possible to improve performance, particularly water resistance.

As described above, the plastic primer of the present invention can be applied to a wide range of various plastic materials, and can be applied to a multi-layer coating obtained by applying the primer coating, intermediate coating, and/or top coating. The film has significantly improved weather resistance, adhesion, chemical resistance, impact resistance, etc. compared to conventional lano.

Furthermore, since the primer coating film of the present invention has excellent smoothness, the gloss clarity of the top coated surface is omitted and is good.

Furthermore, as seen in the example of conventional lacquer-type polyolefin primers, environmental changes (heat,
The thermosetting type brimer of the present invention can avoid the cracking phenomenon caused by so-called cold/heat cycle stress caused by humidity, etc.

Hereinafter, the plastic primer of the present invention will be explained in more detail.

U-Tei±" Consists of (a) an ethylene-propylene copolymer graft-polymerized with maleic acid and (b) a copolymer of a polymerizable unsaturated vinyl monomer mixture containing 2 to 80% by weight of a functional monomer. , and (a)/(b) is 9515 to 40/60 based on the weight ratio, and at least a part of the component (b) is graft polymerized to the component (a).

Plant (broad: ethylene/propylene copolymer made by graft polymerizing maleic acid).

The ethylene-propylene copolymer produced by a conventional method can be used, and the ratio of both components in the copolymer is not particularly limited, but the molar ratio of ethylene/propylene is 20/80 to 80/20. It is preferable that it is within the range of . In addition, the static glass transition temperature (Tg point) of the copolymer is 0°C or less, preferably -20 to -60°C.
'C, especially at -40 to -60°C: i! It is desirable to maintain the following conditions in order to significantly improve the impact resistance of the coating film, and the Tg point can be adjusted arbitrarily by adjusting the composition ratio of both components, the crystallinity of the copolymer, the copolymerization catalyst, etc. . and,
The crystallinity of the copolymer was determined to be 2°0 to 20° by Xi diffraction.
It is strange that it is within the range of %.

The grafting reaction of maleic acid onto the ethylene-propylene copolymer is carried out by a known method. For example, maleic acid is added to the copolymer in an organic solvent (e.g., toluene, xylene, etc.) in the presence of a Lanocal polymerization initiator. Graft polymerization is carried out by heating to 120-160'C while adding acid. In the present invention, maleic acid also includes maleic anhydride. An ethylene-propylene copolymer obtained by graft polymerizing maleic acid (
The content of maleic acid in component n) is 0.5 to 1
A range of 0% by weight, particularly 1% to 5% by weight, is suitable.

If the maleic acid content is less than 0.5% by weight, the adhesion to plastic parts and interlayer adhesion with intermediate coatings and top coatings may deteriorate, and if it is more than 10% by weight, water resistance may decrease. There is. Further, the Tg point of the component (a) is also preferably within the above range for the ethylene-propylene copolymer. By graft polymerizing maleic acid, the adhesion of the primer coating to other coatings and plastic substrates (substrates to be coated) is significantly improved. In the above graft reaction, it is preferable that most or all of the maleic acid is graft-polymerized, but if a large amount of unreacted maleic acid remains, it is desirable to remove this.

Regarding component (a), its Mooney viscosity is ML1□
(at 100°C), it is preferably within the range of 10 to 100, especially 20 to 70. If it is less than 1o, the rupture strength of the formed coating film will be low and the viscoelasticity will be insufficient, so there is a risk that impact resistance etc. cannot be sufficiently improved. , while 100
The larger the Jti polymer, the higher the crystallinity of the Jti polymer, the storage stability of the paint, the copolymer's sedimentation, and the tendency to increase viscosity. Therefore, there is a risk that the impact resistance, especially at low temperatures (below -30°C), may deteriorate.Mooney viscosity is JIS K-630.
It was measured according to the method specified in Section 0-4.

0sJ (Sir: 2 to 80% by weight of functional vinyl mo/mer)
A copolymer of a mixture of polymerizable unsaturated vinyl monomers containing functional vinyl monomers and non-functional vinyl monomers.

The functional vinyl monomer is a polymerizable unsaturated vinyl monomer having a functional group selected from a carboxyl group, a glycite group, an amide group, a flukoxysilane group, a hydroxyl group, etc. and an associative unsaturated bond, and examples thereof include the following. .

(i) Carboxyl group-containing vinyl monomers: for example, acrylic acid, methacrylic acid, crotonic acid, itaconic acid,
Maleic full, maleic anhydride, 7-malic acid, etc.

(ii) Glycytyl group-containing vinylmore 7-2, such as glycinol acrylate, glycityl methacrylate, allyl glycidyl ether, and the like.

(To) Amide group-containing and nil monomers: For example, acrylamide, N-methylol acrylamide, N-butoxymethyl acrylamide, etc.

6→Flucoxysilane group-containing vinyl monomer 12 For example, γ-methacryloxytrimethoxysilane.

(v) Hydroxyl group-containing vinyl monomers: e.g. hydroxyethyl 7-acrylate, hydroxyethyl methacrylate
F, C2-6 hydroxyalkyl ester of acrylic acid or methacrylic acid such as hydroxypropyl acrylate and hydroxypropyl methacrylate, an adduct of the carboxyl group-containing vinyl mo/mer of (i) above and a monoepoxy compound (e.g. Cardura E-10) , above (i
Adducts of i) of the vinyl monomer containing a glycityl group and monocarboxylic acids (eg, acetic acid, propionic acid, oleic acid, lauric acid, p-lebutylbenzoic acid, etc.).

As the functional vinyl monomer, one or more fi selected from the above (i) to (V) can be used, especially G
It is preferable to use a hydroxyl group-containing vinyl monomer selected from v) to 1. .

The non-functional vinyl monomer copolymerized with these functional vinyl monomers is a polymerizable unsaturated vinyl monomer that does not have the above-mentioned functional group.

For example, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, hexyl acrylate, octyl heptaacrylate, lauryl acrylate, cyclohexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl tutaacrylate. , isopropyl methacrylate, butyl methacrylate,
C4-, 4-alkyl or dichlorofurkyl esters of acrylic acid or methacrylic acid such as hexyl methacrylate, octyl methacrylate, lauryl methacrylate, cyclohexyl methacrylate; methoxybutyl acrylate, methoxybutyl methacrylate, methoxyethyl acrylate;
Flucoxyfurkyl esters of acrylic acid or methacrylic acid such as methacrylic acid/toxyethyl, ethoxybutyl acrylate, and ethoxybutyl methacrylate; styrene;
Vinyl aromatic compounds such as α-methylstyrene, vinyltoluene and vinylpyridine;
Meth)acrylate; examples include acrylonitrile and methacrylatetrile. Two or more types of these non-functional vinyl monomers can be used as 1M, and among these, the alkyl ester or cycloalkyl ester of acrylic acid or methacrylic acid can be used in an amount of 30% by weight or more in the non-functional monomers. preferable.

In addition, the copolymer constituted by the component (b) preferably has a low quiet lath transition temperature, like the components (,), specifically -10°C or less, particularly -20 to - 4
The temperature is preferably 0°C.

In the component (b), a functional vinyl heptamine
The composition ratio of is 2 to 80% by weight, preferably 1/l+9() to ^ based on the total weight with the non-functional vinyl monomer.
If the amount of functional enzyme bv nirki/mer is less than 2% by weight, the crosslinking reactivity of the acid component [B] will decrease, resulting in a decrease in water resistance, acid-chemical resistance, adhesion, weather resistance, etc. If the amount exceeds 80% by weight, curing will progress too much and impact resistance, smoothness,
Both are unfavorable because the adhesion properties deteriorate.

[A] Acid component This is a graft combinatorial reaction of the above components (a) and (b), and this graph 1 reaction can be carried out in the same manner as in the synthesis of ordinary acrylic material 4 resin. For example, it can be carried out using a solution polymerization method, an emulsion polymerization method, a suspension polymerization method, or the like.

Preferably, v1 is carried out according to the solution a polymerization method.

According to the solution polymerization method, component (tl) is dissolved in a suitable organic solvent, and a functional vinyl monomer and a non-functional vinyl monomer as component (b) are added thereto together with a lanocal polymerization initiator. 0-180°C, preferably 40-1
Graft polymerization can be carried out by reacting at a reaction temperature of 70° C. for about 1 hour to 20:00, preferably for about 4 to 10 hours.

Examples of organic solvents include aliphatic hydrocarbons such as pentane, hexane, cyclopenkune, cyclohexane, heptane, methylcyclohexane, and isooctane; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, and noethylbenzene; and hydrogen such as tetralin and decalin. Solvents selected from added aromatic hydrocarbons and the like can be suitably used, and organic solvents such as alcohols, esters, ethers, and ketones can also be used in combination.

Further, as the radical polymerization initiator, for example, azo compounds, peroxide compounds, sulfides, sulfines, noazo compounds, nitroso compounds, redox compounds, etc. can be used.

As mentioned above, in this graft polymerization reaction, both vinyl monomers of component (b) are added to an organic solution of component (a), and the two vinyl monomers are copolymerized and graft polymerized to component (,). It is preferable that (b)
It is also possible to copolymerize both vinyl monomers in the components in advance and react them with component (a).

In these graft polymerization reactions, it is most preferable that all of component (b) is graft-polymerized with all of components (,), but it is preferable that components (,) and (b) remain unreacted in the system. , graft polymer, component (a) and (
The three components of component (b) (copolymer) may be mixed together.

The composition ratio for graft polymerization of components (,) and (b) is 95/5 to 40/60 (component (a)/component (b)) based on the total weighting ratio of the same components.
, preferably in the range of 80/20 to 60/40, particularly preferably in the range of 75/25 to 65/3S. If component (a) is less than 1% by weight of 40%, deltation is likely to occur during graft polymerization, and if the molecular weight is limited to a low value to prevent this deltation, impact resistance will decrease and component (a) will be less than 95% by weight.
If it exceeds 1% by weight, the adhesion to plastic members and other coatings and water resistance will deteriorate, which is not preferable.

is a crosslinking agent for two-dimensionally crosslinking and curing the component [A].

[B] As the acid component, a compound capable of crosslinking and curing by reacting with the functional group (b) in the component [A] that is twisted at 2'' in 71 minutes is used, and is selected as appropriate depending on the functional group in the component (b). Specific examples of crosslinking agents that can be used are as follows, based on the functional groups in (b)/&. Bis7e/-
Type A hydrogenated epoxy resin aliphatic epoxy resin triglycidyl in cyanurate, other polyepoxy compounds (ii) Glycidyl group: Aliphatic nocarboxylic acid: fatty acid ester carboxylic acid-containing acrylic in the layer for aromatic epoxy, such as decanedicarboxylic acid, Furukito, Polyester (
Fat (to) Amide group: Bisphenol A type aromatic epoxy fat
/ Return the epoxy to 1 fatty acid epoxy resin triglycidyl in cyanurate, 6) Furufukidisilane group, hydroxyl group 1 Using a graft polymer of component (b) containing a hydroxyl group-containing vinyl monomer as a component, a crosslinking agent ([B] as an acid component, amino/resin, polyincyanate compound and 1 block) The use of selected incyaneto compounds is particularly effective in improving impact resistance, physical performance, weather resistance, water resistance,
Excellent adhesion to the substrate, etc.: This is preferable because it exhibits coating film performance and the coating composition itself has excellent storage stability.

Among the above-mentioned crosslinking agents, suitable amino resins, polyisocyanate compounds and blocked isocyanate compounds include the following.

Amino/resin contains melamine, urea, benzoguanamine, acetoguanamine, steroguanamine,
Manufactured by the reaction of spiroguanamine, dicyanamide, etc. with aldehyde.

Examples of aldehydes to be reacted with amino/components include formaldehyde, paraformaldehyde, acetaldehyde,
Examples include benzaldehyde. Ami7 resin is modified with a suitable alcohol, and examples of alcohols used for modification include methyl alcohol, ethyl alcohol, +1-7" propyl alcohol, i-propyl alcohol, n-butyl alcohol, i- Butyl alcohol, 2-ethylbutanol, 2-ethylhex/-ol, bennor alcohol, lauryl alcohol, ethylene glycol monomethyl ether (methyl cellosolve), ethylene glycol monomethyl ether (ethyl cellosolve)
, ethylene glycol monobutyl ether (butyl cellosolve), noethylene glycol mo/methyl ether glycol mo/ethyl ether (ethyl calpitol), and ethylene glycol monobutyl ether (butyl calpitol). When using hexamethoxymethyl melamine or melamine U4 fat in which a portion of its methoxy group is substituted with C4 or higher alcohol as the fat, a commonly used curing catalyst such as para-toluenesulfonic acid must be added. is preferred.

In addition, polyisocyanate compounds have two or more 'I!' molecules in the molecule. A compound having an L-isolated incyanate group, specifically, tolylene diisoyanate, 4,4'-
Nophenylmethane noisocyanate, xylylene noisocyanate, ivy xylylene diisocyanate, hexamethylene diisocyanate, linone diisocyanate,
Hydrogenated 4+4'nophenylmethanoisocyanate,
Hydrogenated tolylene diisocyanate, inphoronoisocyanate, trinotylhexamethylenenoisocyanate, gimaric acid diisocyanate, adduct of tolylene diisocyanate (3 mol) and trimethylolpropane (1 mol), polymer of tolylene diisocyanate , adduct of hexamethylene diisocyanate (3 mol) and trimethylolpropane (1 mol), reaction product of hexamethylene diisocyanate and water, xylylene noisocyanate (3 mol) and trimethylolpropane (1 mol) ), adducts of tolylene diisocyanate (3 mol) and hexamethylene diisocyanate (2 mol), etc. can be used. Among these, one or more selected from adducts of tolylene diisocyanate (3 mol) and hexamethylene diisocyanate (2 mol) can be used. Reactant of hexamethylene diisocyanate and water, adduct of xylylene diisocyanate and trimethylolpropane, adduct of tolylene diisocyanate and hexamethylene diisocyanate, isophorone diisocyanate), hexamethylene diisocyanate, Non-yellowing types such as lysine isocyanate are preferred.

Since these polyisocyanate compounds easily react with active hydrogen such as hydroxyl groups in component [A] and cure at room temperature, these surrounding components are preferably of a so-called two-component type that are mixed immediately before use.

In addition, if the incyanate group of the polyisocyanate compound is blocked in advance with a blocking agent (then [
A] Acid component does not react, and even if surrounding components are mixed, it does not react during storage and can be made into a one-component type. As such a blocking agent, known ones can be used, such as methanol, ethanol, butanol,
Examples include chlorine, catechol, resorcinol, acetylacetone, malonic acid ester, caprolactam, and the like. These blocking agents dissociate when heated to a temperature higher than the oxidation temperature, free incyanate groups are regenerated, and the [A] acid component undergoes a crosslinking reaction and is cured.

The composition ratio of [A] acid component and [B] acid component can be arbitrarily selected and is not particularly limited, but when using 7mino resin as [B] acid component, the total weight of the surrounding components should be , [A] in 60-90% by weight, 7 ml (preferably in the range of 40-10% by weight.Also, when using polyisocyanate compounds (including blocked products), [A] acid component The blending ratio of active hydrogen groups and NCO groups contained is preferably in the range of NCOO.5 to 1.2 (molar ratio) to 1 active hydrogen group.

The brimer of the present invention has [A] acid component and [B] acid component as main components, and it is preferable to dissolve or disperse these components in an organic solvent and apply the same. Organic solvents include aromatic hydrocarbons such as benzene, toluene, and xylene, aliphatic hydrocarbons such as hexane, heptane, octane, and decane, and chlorine such as trichlorethylene, perchloroethylene, nochloroethylene, nochloroethane, and nochlorobenzene. Hydrocarbons and the like can be used, and organic solvents such as 7-lefur-based solvents can also be used.

The primer may also contain coloring pigments (e.g., titanium white, carbon black, etc.), extender pigments (e.g., asbestos, talc, clay, etc.), and plasticizers (e.g., nooctyl-7-thale, tritium, etc.) as necessary. Cresyl phosphate, diptyl sebacate, etc.), anti-sagging agents (eg, aluminum stearate), silica sol, etc.) can also be blended in appropriate amounts commonly used.

The primer of the present invention has the above-mentioned [A] acid component [B] acid component as its main component, but in order to obtain sufficient technical effects such as impact resistance and adhesion, it is necessary to The glass transition temperature is 0°C or less, preferably -20°C.
'(: It is desirable to adjust l!4 to ~-60"C. The static lath transition temperature of the primer coating film is [the composition of each component (, a), (b) in the A1 component, (,)/(b)
It can be freely adjusted by adjusting the ratio, [[3] component composition, [A]/[[3] ratio, etc.;
or) [It can also be adjusted using, for example, lonone, petroleum resin (coumaron), ester gum, polybutanoene, epoxy-modified polybutanoene, polyoxytetramethylene glycol, etc., which are compatible with component B1.

The amount of these ingredients is the total amount of [A] and [I3] components: 100
50% by weight! l! It is desired that the amount is 1 part or less, preferably 25 parts or less.

In the present invention, the static glass transition temperatures of the components (a), (b) and the primer coating are measured with components (,) and (b) excluded from any liquid components such as solvents. The primer coating was coated to a thickness of 25μ based on the cured coating and baked at 120°C for 30 minutes.
SC-10 model), and is defined as the temperature at which the main dispersion peak (50% or more of the total) appears.

Furthermore, the primer coating film has a breaking strength elongation rate of -20
By adjusting the tensile strength to 30% or more, especially 50% or more at a tensile rate of 20 wm/min in an atmosphere of 0.degree. C., the impact resistance of a multilayer coating film can be further improved. "Tensile breaking strength elongation rate" is 8! Universal tensile test with constant temperature oven! (Shimadzu Auto Club Model S-D) was used, and the quality of the sample was 20.
al+11, tensile speed measured at 20+6111/min r
This value is The samples used for these measurements were coated with the primer on a tin plate to a thickness of 25μ based on the dried coating film formed, baked at 120°C for 30 minutes, and then isolated using the mercury amalgam method. It is something.

Since the primer of the present invention has excellent adhesion, it can be applied to most plastics with different surface conditions, such as polyamide 8.
4 N <nylon), polyethylene terephthalate resin, polyphenylene oxide υ (fat), SMC (unsaturated polyester resin), high-rigidity polypropylene resin, high-rigidity polyurethane 84 resin, phenol! ) Plastic, soft polypropylene, soft polyurethane resin, ABS thin Jr.
'r (WI for acrylonitrile, butanoene, styrene copolymerization), polycarbonate utm, vinyl chloride F3f
Low heat deformation temperature (approximately 100℃) such as oil, acrylic resin, etc.
(below) plastics, as well as plastics reinforced with glass fiber or whiskers. Examples include polymer alloys (for example, polycarbonate-polybutylene terephthalate, polycarbonate-ABsa[t, polyamitom (fat-polyphenylene oxide, styrene-polyphenylene oxide), etc.).

Specific examples of using these plastics include the outer parts of automobiles, automobile interior instrument panels, air conditioners, seat structure parts, door mirrors, door sashes, parts of the motorcycle 1117 engine, trunk gasoline tanks, lanterns, and home appliances. Examples include plastic parts of products, general buildings, agricultural equipment, and toys.

The primer of the present invention is applied to the above-mentioned plastic directly or while the surface is treated by a conventional method. The method of coating the primer is not particularly limited, and examples include spray coating, brush coating, dipping coating, melt coating, electrostatic coating, etc. The coating Vt film thickness is 1 to 20μ based on the dry and cured coating.
, particularly preferably 3 to 7μ. The primer coating film is preferably cured by heating at room temperature to 160°C (especially 80 to 160°C). It can be appropriately selected depending on the temperature.In addition, when applying another paint to the surface of this primer coating, the primer coating can be either cured or uncured.

The plastic coated with the primer of the present invention can be coated with an intermediate coat, if necessary, and then coated with a top coat.

As the intermediate coating, any known intermediate coating that has excellent adhesion, smoothness, brightness, weather resistance, etc. can be used.

Specifically, there may be mentioned a thermosetting intermediate coating whose vehicle main components are a short oil or ultra-short oil alkyd resin having an oil length of 30% or less, or an oil-free polyester resin and a 7-7 resin. These alkyd resins and polyester resins have a hydroxyl value of 60 to 140 and an acid value of 5 to 200,
Moreover, unsaturated oil (or unsaturated fatty acid) is a denatured oil.
It is preferable to use a 7-mino resin, and suitable alkyl (preferably one having 1 to 5 carbon atoms) etherified melamine resin, urine xmm, benzoguanamine resin, and the like. The blending ratio of these two resins is based on solid content weight: 65% to 85%, especially 70% to 80%, of oil-free polyester resin, 35% to 15%, especially 30% to 20%, of amino resin, based on solid content weight. It is preferable that there be.

Furthermore, at least a portion of the above amino resin can be replaced with a polyisocyanate compound or a blocked polyincyanate compound.

The form of the intermediate coating is most preferably an organic solution type, but it may also be a non-aqueous dispersion type, high solid type, aqueous solution type, aqueous dispersion type, powder type, etc. using the above vehicle components. do not have. Furthermore, the intermediate coating paint includes an extender pigment,
Coloring pigments, paint additives, etc. can be added as necessary.

These intermediate coatings are paints that are applied to the surface of the primer coating, and can be applied in the same manner as the primer, and the coating HtA thickness is 10 to 50 μm based on the cured coating. It is preferable that the curing temperature of the coating film is within the range of
::Lf) Preferably, the heating is performed at a temperature in the range: ::Lf).

A top coat is a paint that is applied to the surface of a primer coat or intermediate coat, and is used to impart cosmetic properties to an object to be coated. Specifically, the finished appearance (sharpness, smoothness,
Uses known paints that form coatings with excellent properties such as gloss (gloss, etc.), weather resistance (gloss retention, color retention, chalking resistance, etc.), chemical resistance, water resistance, moisture resistance, hardening properties, etc. I can do it,
For example, there are paints whose vehicle main components are amino-acrylic resins, amino-alkyd resins, amino-polyester resins, etc. Furthermore, some or all of these 7-mino resins are mixed with polyisocyanate compounds or block polyesters. Paints using isocyanate compounds may also be used. The form of these paints is not particularly limited, and may include organic solution type, non-aqueous dispersion type, water-soluble (molecule 11.) wL type, powder type,
Any form of lano, such as a high solid type, can be used. Drying or curing of the coating film is carried out by drying at room temperature, heating drying, irradiation with active energy rays, etc.

The top coat used in the present invention can be either an enamel pigment, which is a paint whose main component is the vehicle described above, mixed with a metallic pigment and/or a colored pigment, or a clear paint, which does not contain any or almost no pigment. It may be something. Then, use these paints to
Examples of methods for forming the S film include the following: ■ Applying a metallic paint containing a metallic pigment and, if necessary, a colored pigment, or a solid color paint containing a colored pigment. , heat curing method (
(Metallic or solid color finish using 1 batch, 1 bake method).

■Paint with metallic paint or solid color paint,
After being heated and cured, a clear coating is applied and the material is heated and cured again (metallic or solid color finish using 2-coat, 2-beam method).

■Paint with metallic paint or solid color paint,
Subsequently, a clear paint is applied and then heated to cure both paint films at the same time (metallic or solid color finish using a two-fleet one-bake method).

These top coats include spray painting, electrostatic painting, etc.
It is preferable to paint, and the coating y and film thickness are based on the dry coating film, in the range of 25 to 40μ in the above (■), and in the range of 10 to 30μ for metallic paints and solid color paints in the above (■). The clear paint preferably has a number in the range of 25 to 50. Heat curing conditions can be arbitrarily selected depending on the material of the object to be coated, vehicle components, etc., but generally 60 to 160°C, especially 100 to 150°C, 10 to 100°C.
Preferably, it is heated for 40 minutes.

Moreover, if the primer of the present invention contains conductive powder, the primer can be used! ! 2! Preferably, the intermediate or top coat can be electrostatically applied to the coated plastic component.

Next, examples and comparative examples related to the present invention will be described.

! -10 Ton J Go J Shi Sockeye Salmon [A-1]: Equipped with a stirrer, a monomer dropping device, a catalyst dropping VC device, a 7-lux condenser, and a thermometer, and has an internal volume of about 5,000
In the cc reactor, as component (a), maleic anhydride was grafted and the content was 3.5% by weight. The viscosity is M L ''(t
oo"c,: 68) 70 parts by weight and 1,880 parts by weight of toluene are charged, and the solid components are dissolved while heating and stirring until a uniform solution is obtained.

Next, while maintaining the solution temperature at 100±5°C, as the component (mountain),
A mixture consisting of butyl acrylate 3.3〃methyl methacrylate) 0.6 #acrylic acid 0.3〃, a mixture consisting of 1.2 weight xi of polymerization catalyst benzoyl peroxide and 10 weight parts of toluene were added as monomers, respectively. The catalyst is dropped over a period of 3 hours using a dropping device and a catalyst dropping device. Thereafter, stirring of the reactant is continued until the reaction is completed, and the temperature of the reactant is adjusted to 100±5°C.

After aging for 1 hour after the completion of the monomer and catalyst dropwise addition, azobisisovaleronitrile 0 was added as an additional catalyst.
．． 1 part by weight of a mixture consisting of 5 parts by weight and 10 parts by weight of toluene.
Drop it over 30 minutes.

After aging for 1 hour, the reactant is gradually cooled, and when the temperature of the reactant becomes 40° C. or less, the reaction product is taken out.

◆ The characteristic values of this reaction product were as follows.

(a) / (1)) ratio: 70/30 [ff1l ratio 1 (a) Static Tg: -56 ['CJ mountain) component Static Tg: -25,1 ['C]OH number: 71
．． 3 [lJ gram KOH]/[gra-A lenone 1 oxidation: 32.3 [] [A-2]: <a) Ethylene to which maleic anhydride is grafted as a component and whose content is 2.0% by weight -Propylene copolymer (ethylene/propylene ratio near 0/365 parts by weight, false) I & min 2-ethyl hydroxy 7 acrylate 14 parts 10 im butyl methacrylate 10 rope 7 acrylic) 10 II methyl methacrylate 0.65 it acrylic The reaction product [A-21] was obtained in exactly the same manner as in the production of [8-11, except that 1 part by weight of 35% of the mixture consisting of acid O*357/ was used. [
A-2] had the following characteristic values.

(a) / (b) ratio: 65/35 [ff1l ratio]
(,) component Static Tg: -52BiC] (b) component
Static Tg: -31, 1['C]OH value: 66.
7 [milligram K OH] / [gram Renone 1 oxidation: 27.4 [// ] / [// ]
[A-3]: 75 parts by weight of the maleic acid grafted ethylene-propylene coelectrolyte used in the 91 production of [A-1] as the component (a), and 7.5 parts of 2-hydroxyethyl acrylate as the component (mountain). Inbutyl methacrylate) 5.2 /1n-butyl acrylate 11.4 11 Methyl methacrylate 0.7 Acrylic acid
Reaction product [A-3] was obtained in exactly the same manner as in the production of [A-13] except that a mixture consisting of [0.2] was used. Characteristic values are shown below.

(a) / (b) ratio: 75/25 [weight ratio 1 (a
) component Static'r,,,: -48BiC1(b) component Static Tg: -36,7 ["C108 valence: 42
, 8 [milligram KOHI/[gram resin] Oxidation: 32.6['/ ]/[N][A
-41 (for comparison) The amount of maleic acid grafted ethylene-propylene copolymer used in the production of [A-1] as component (a) was 30 parts by weight, and as component (b) 2-hydroxyethyl acrylate 14 Parts by weight: inbutyl methacrylate 24 n-butyl acrylate 30 methyl methacrylate 1.3' 4.2 parts by weight
A reaction product [A-41] having the following characteristic values was obtained by the same operation as in the production of [A-1].

(,) / (b) ratio: 30/70 [weight ratio] (,
) component Static Tg: -48 ['C] (b) component Static Tg: -24,6 ['C] O0 valence: +3G,
+3 [milligram KOII] / [gramlenone 1 oxidation: 19.7 ['/ ] / [〃 ] [A
-5] (for comparison) The (,) component is the maleic acid graphene-propylene copolymer used in the production of [A-13, and the mountain) component is inbutyl methacrylate 9. O parts by weight rope methyl acrylate) 19.5 /1 methyl methacrylate) 1.2 #acrylic acid
A reaction product [A-5] having the following characteristic values is obtained by performing exactly the same operation as in the production of [A-1], except for using a mixture consisting of 0.3.

(u)/middle) Ratio 0/30 [weight 1%] (a) Component Static "rg: -ss BiC1 (b) a Static Tg:
-,24,3 pC]○I-[Value: 0. O [milligram KOH] / [gram resin 1 Acid value: 28,8 [# ] / ['/ ] [A
-G] (for comparison) Except for using an ethylene-propylene copolymer (33:67 molar ratio), the same operation as in the production of [A-1] was performed to produce the reaction product [A-6] I got it.

The characteristic values of [A-6] are as follows.

(+1)/Φ) ratio: 70/30 [wt%] (a) component Static Tg: -46BiC1 mountain) component Static Tg:
-25,1 BiC101-1 value: 70.6 [milligram KOII] / [Gellum resin 1 acid value: 4.4 [// ] / [// ]■
[4] The reaction products obtained in [A-1] to [A-5] above ([A
] ingredients) were used to prepare a primer having the composition and blending amount shown in Table 1.

In Table 1, (i) Nikalac MX-485 is a trade name manufactured by Sansho Chemical Co., Ltd. and is a butoxy-methoxy modified melamine resin (non-volatile content: 85% by weight).

GO Cynor 350 is a trade name manufactured by American Anamide Company, USA, and is hexamethoxymethylmelamine.

(a) The blocked isocyanate compound is obtained by blocking the incyanate group of hexamethylene diisocyanate with 7-cetylacetone.

Gv) J R-600 is a trade name of Teikoku Kako Co., Ltd. and is a rutile-type titanium oxide pigment.

(v) Catalys) 6000 is a trade name of Mitsui Toatsu Chemical Co., Ltd. and is dodecylbenzenesulfonic acid.

(All vO blending amounts are parts by weight of solid content, and were adjusted with toluene to a viscosity suitable for spray coating.

■, Method 1] Collection (Somai) The primer for plastics obtained in the above ■ was applied to various plastics, and then a coating film performance test was conducted using a coated plate prepared by applying an intermediate coat and a top coat.Painting process and coating film performance are shown in Table 2.

In Table 2, (1) Primer m: The names are based on the description in Table F51, of which (C) is a primer for chlorinated polypropylene-modified polyurethane plastics.

(2) Plastic member 2, large! :(8X15XO
.

3CI11) (a) Polyamide resin plate, ([1) Polybutylene terephthalate Japanese resin, (c) Polyphenylene oxide resin, (d) Highly rigid polypropylene 0 (Pilgrimage, (e) Soft polyurethane resin, (f) Polycarbonate) - ABSυ (polymer alloy) (3) Intermediate paint: (A) Amirac N-2 Sealer (Kansai Paint■
manufactured by Ami/-polyester resin intermediate coating).

(4) Top coat paint: (A) Amylac White [manufactured by Kansai Paint ■, amino-alkyd resin top coat paint, white paint for 1 batch 1 bake, pencil hardness H (20°C)] (B) Solex #200 White [manufactured by Kansai Paint 0, urethane-cured polyester topcoat paint, 1-coat 1-bake 2-component white paint, pencil hardness HB (20'C)], hardener Duranate 24A (Asahi Kasei Industries @tJI) (5) Painting Based on the cured coating with the method Primer Painting Nispray 6~
It was painted to a thickness of 10μ and baked for 20 minutes at 120'.

Based on the cured film, it was coated with intermediate coat varnish spray to a thickness of 30μ and baked at 140'C for 20 minutes.

Based on the cured coating, paint with a topcoat varnish spray to a thickness of 35μ, and (A) is baked at 140℃ for 20 minutes, ([
13) was cured by heating at 80°C for 30 minutes.

(6) Add 1 piece of adhesive 1 piece of paper to the top of the cloth, insert 1 piece of paper, 1 piece of fake rice, and 04 pieces of paper to remove the film, and move 180 degrees along the notch to 2011s/
The force required to peel off the coating film at the speed of papermaking (20°C) was expressed in units of g/c+o.

(7) Water resistance: The coated surface after being immersed in water at 40° C. for 30 days is evaluated.

◎: No abnormality, O: Slightly small 7 cracks, Δ: Slight 7 cracks, ×: Hedges (8) Impact resistance: JIS K5400-1979 f3.13.3B
According to the law, the product of the weight of the dust and the falling height at which the plastic material breaks when a weight is dropped is expressed as 111 (kg-cm) in an atmosphere of -30°C.

(9) Accelerated weather resistance: Sunshine Weather-Ometer 100015@lj [Evaluate the condition of the painted surface after spraying.

◎ No abnormalities on the painted surface. Δ Slight peeling occurs × 7 creases, 8 creases occurred

Claims (1)

[Claims] [A] (a) Ethylene graft-polymerized with maleic acid.
Propylene copolymer and (b) 2 to 8 functional monomers
a copolymer produced from a radically polymerizable unsaturated monomer mixture containing 0% by weight, and (a)/(b
) is 95/5 to 40/60 based on the weight ratio,
A primer for plastic members, the main components of which are a resin composition in which at least a part of the component (b) is graft-polymerized to the component (a), and [B] a crosslinking agent.