JP3086286B2 - Painted soft automotive parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible automobile member in which a paint is directly applied to a surface of a molded article.

[0002]

2. Description of the Related Art Conventionally, automobile parts made of propylene-based soft resin used as exterior members such as bumpers, spoilers, mudguards, side moldings, wheel caps and the like, as instrument panels, levers, knobs, linings, etc. are widely used. In some cases, the whole or a part thereof is painted and put to practical use. However, since these propylene-based soft resin automobile members do not have a polar group in the structure of the material itself, it is difficult to obtain a practical level of paint adhesion strength when directly applying a paint. Was. For this reason, in many cases, the paint adhesion performance of the automobile member is improved by applying a primer (primer coating method) to the surface of the preformed automobile member or performing a plasma treatment (plasma treatment method).

[0003]

However, such a coating method has conventionally had the following problems. That is, the primer coating method has disadvantages such as the necessity of using an expensive primer and the increase in the number of coating steps, which increases the coating cost. In addition, there is a risk that fire may occur due to the necessity of volatilizing the solvent in the primer, and thus there is a problem in safety. On the other hand, in the plasma processing method, since a high vacuum state is required, expensive equipment must be installed, and
Due to the batch method, an increase in cost could not be avoided. Furthermore, the surface after the plasma treatment is unstable, and the adhesion of the coating material is reduced when it comes into contact with foreign matter, so that the coating film performance tends to vary, and handling is extremely inconvenient. Therefore, if the primer coating and the plasma treatment steps in the coating of automotive parts made of propylene-based soft resin can be omitted, the coating step can be simplified, the working environment can be improved, and the cost can be reduced. Since it is possible, much research has been done to achieve the omission of these steps. However, in the end, this purpose has not yet been achieved, and automotive parts made of a propylene-based soft resin cannot omit such primer coating or plasma treatment, and are coated after performing these treatments. .

[0004]

[Means for Solving the Problems]

[Summary of the Invention] The present inventors have conducted intensive studies to achieve the above object, and as a result, molded using a propylene-based soft resin composition of a specific material and composition containing a small amount of filler. Despite the direct application of paint, automobile parts have mechanical strength, hot water resistance and paint adhesion performance, and hardly increase the specific gravity or rigidity, impairing the physical properties of a soft resin Based on the finding that there is no such compound, the present invention has been completed.

That is, the coated soft automobile member of the present invention comprises the following components (a) to (e) and has a resin composition having a flexural modulus (JIS-6703) of 10,000 kg / cm ² or less. The coating film is formed directly on the surface of the molded article. Component (a): contains 4 to 30% by weight of a room temperature xylene-soluble component having an ethylene content of 20 to 70% by weight, and has an MFR of 1 to 200 g / 10 minutes and an ethylene content of 3
Propylene / ethylene block copolymer of ２１21% by weight: 30-70 parts by weight (b) Component: selected from ethylene-based elastomer, hydrogenated styrene / butadiene block copolymer and hydrogenated styrene / isoprene block copolymer And at least one elastomer: 70 to 30 parts by weight, based on 100 parts by weight of the total of components (a) and (b), component (c): a diene polymer having a hydroxyl group at a terminal or a hydrogenated product thereof: 0.1 to 25 parts by weight (d) component: a copolymer of ethylene and a carboxyl group-containing unsaturated compound or a mixture of ethylene and a carboxyl group-containing unsaturated compound At least one selected from ionomers in which at least a part of the carboxyl groups in the copolymer of the above is neutralized with a transition metal cation: 0 1-25 parts by weight of component (e): a specific surface area of 37,000cm ² / g or more, is substantially 15μm or less in length, the average particle diameter of 0.8 to 3.0
talc having an average aspect ratio of 5 or more, aluminum borate whisker having an average diameter of 2 μm or less and an average aspect ratio of 5 or more, whisker of potassium titanate, and whisker of magnesium sulfate [magnesium oxysulfate whisker MgSO ₄ .5Mg (OH)
₂ · 3H ₂ O], the titanium oxide whiskers, also a kind of filler less selected from the calcium whiskers and calcium carbonate: 0.01 to 7 parts by weight

DETAILED DESCRIPTION OF THE INVENTION [I] Molded Resin Composition (1) Component (a) Component: Propylene / Ethylene Block Copolymer The propylene / ethylene block copolymer (a) used in the present invention. The polymer has an ethylene content of 20.
It contains 4 to 30% by weight, preferably 6 to 25% by weight, of a substantially amorphous room temperature xylene-soluble matter of about 70% by weight, and has an MFR (230 ° C., 2.16 kg) of the whole copolymer. 1 to 200 g / 10 min, preferably 2 to 100 g / 10 min
The ethylene content is 3 to 21% by weight, preferably 3 to 21% by weight.
18% by weight of resin can be mentioned. Here, the ethylene content is a value measured by an infrared absorption spectrum analysis method or the like.Also, the xylene-soluble component at room temperature is dissolved in 2 g of a sample in 500 g of boiling xylene for 20 minutes, and then cooled to room temperature. The MFR is a value calculated in accordance with JIS-K7210 by back-calculating from the solid phase weight obtained by filtering and drying the precipitated solid phase through a glass filter. Here, a copolymer containing a large amount of kylene-soluble components at room temperature is advantageous because the coating strength is improved. Those whose ethylene content and room temperature xylene solubles in this copolymer resin are less than the above ranges are inferior in impact resistance when used as an automobile member, while those exceeding the above ranges are The rigidity is insufficient. Further, the MFR is limited to the above range for reasons such as a decrease in mechanical strength such as moldability and impact properties. For the production of this copolymer resin,
Conventional stereoregular catalysts are used. This propylene
The ethylene block copolymer may be used in combination with other unsaturated monomers (for example, butene) without significantly impairing the effects of the present invention.
1, α-olefins such as hexene-1; vinyl esters such as vinyl acetate; unsaturated silane compounds such as vinyl trimethoxysilane; (meth) acrylic acid (ester);
It may be a ternary or higher copolymer containing an unsaturated organic acid such as maleic anhydride or a derivative thereof (which may be any of a graft type, a random type and a block type).

Component (b): Elastomer In the present invention, the elastomer of the component (b) may be an ethylene / propylene binary copolymer rubber (EPM) or an ethylene / propylene / non-conjugated diene terpolymer rubber (EPD).
M), ethylene-based elastomers such as ethylene-butene-1 copolymer rubber and ethylene-propylene-butene-1 terpolymer rubber, hydrogenated styrene / butadiene block copolymer, and hydrogenated styrene / isoprene block copolymer At least one selected from coalescence can be used. Ethylene / propylene binary copolymer rubber (E
PM) has a propylene content of 20 to 55% by weight, preferably 25 to 55% by weight, and a Mooney viscosity (ML _{1 + 4} 100
C.) of 10 to 100, particularly 15 to 90. The ethylene / propylene / non-conjugated diene terpolymer rubber (EPDM) preferably has an iodine value of 20 or less, particularly 18 or less. The ethylene / butene-1 copolymer rubber has a butene-1 content of 5 to 30% by weight, preferably 1 to 30% by weight.
Those having 0 to 25% by weight are preferred. The ethylene-propylene-butene-1 terpolymer rubber has a propylene content of 20 to 55% by weight, preferably 25 to 50% by weight, and a butene-1 content of 3 to 15% by weight, preferably 5 to 1%.
Those with 2% by weight are preferred. Here, the content of each component is a value measured by a conventional method such as an infrared absorption spectrum analysis method and an NMR method. Further, the degree of crystallinity of these rubbers is preferably 30% or less. The production method and shape are not particularly limited. The hydrogenated styrene / butadiene block copolymer and the hydrogenated styrene / isoprene block copolymer are completely or partially hydrogenated, respectively, so-called styrene / ethylene / butylene / copolymer.
It is expressed as a styrene block copolymer or a styrene / ethylene / propylene / styrene block copolymer. Usually, the degree of hydrogenation is 95% or more, but preferably 99% or more. The styrene content is preferably from 5 to 50% by weight, particularly preferably from 15 to 50% by weight. Among these elastomers, those having properties within the above range are particularly preferred in terms of coating performance and balance of properties.

Component (c): Diene polymer having a hydroxyl group at a terminal or a hydrogenated product thereof The component (c) used in the present invention includes a diene polymer having a hydroxyl group at a terminal or a hydrogenated product thereof. Examples of the diene polymer having a hydroxyl group at a terminal include polyhydroxypolybutadiene. Specifically, it has at least one hydroxyl group at a terminal and has a molecular weight of 200 to 100,000, preferably 5 to 100,000.
00 to 50,000, particularly preferably 800 to 10,000.
And room temperature liquid, semi-solid and solid polymers. The average number of hydroxyl groups per molecule is generally preferably from 1 to 10, particularly preferably from 1.5 to 5, and the hydroxyl value is generally from 15 to
250, preferably 25 to 125 (KOH mg / g). The diene polymer having a hydroxyl group at the terminal can be produced by a known method, for example, a radical polymerization method or an anion polymerization method, using 1,3-diene as a raw material. Specifically, for example, Japanese Patent Application Laid-Open No. 51-7139
No. 1 publication can be mentioned. When this is produced by radical polymerization, it can be easily obtained by polymerizing a diene monomer using hydrogen peroxide as a polymerization initiator. In the case of production by anionic polymerization, at least one of both terminals obtained by polymerizing a common diene using an anionic polymerization catalyst, for example, an alkali metal or organic alkali metal compound, according to a well-known method. For example, a monoepoxy compound, formaldehyde, acetaldehyde, acetone,
Alternatively, a halogenoalkylene oxide, a polyepoxide, or the like may be reacted. At least one kind of conjugated diene monomer is used as a raw material monomer for these polymers. Examples of the conjugated diene monomer include 1,3-butadiene, 1,3-pentadiene, isoprene, chloroprene, 2,3-dimethyl-1,3-butadiene, and 1-phenyl-1,3-butadiene. The hydrogenated diene polymer having a hydroxyl group at the terminal is obtained by hydrogenating the diene polymer having a hydroxyl group at the terminal described above by a usual method, for example, a method described in JP-A-51-71391. It is obtained. The degree of hydrogenation may be such that the double bond contained in the polymer is completely or partially hydrogenated, but the iodine value is usually 0 to 20, especially 0 to 5
(G / 100 g) is preferred. These diene polymers having a hydroxyl group at the terminal or hydrogenated products thereof can be used alone or as a mixture of a plurality of them.

Component (d): Ethylene / unsaturated carboxylic acid copolymer or ionomer The ethylene / unsaturated carboxylic acid copolymer is a copolymer of ethylene and an unsaturated carboxylic acid. As the unsaturated carboxylic acid, an unsaturated carboxylic acid having 3 to 8 carbon atoms,
Specifically, acrylic acid, methacrylic acid, itaconic acid,
Maleic anhydride, maleic acid monomethyl ester, maleic acid monoethyl ester and the like are used. Among these unsaturated carboxylic acids, acrylic acid and methacrylic acid are particularly preferably used. The ethylene / unsaturated carboxylic acid copolymer may contain a third component in addition to ethylene and the unsaturated carboxylic acid as described above. Examples of such a third component include ethyl acrylate and acrylic acid. i-butyl,
Unsaturated carboxylic esters such as n-butyl acrylate and methyl methacrylate, and vinyl esters such as vinyl acetate are used. The ethylene / unsaturated carboxylic acid copolymer has an ethylene content of 50 to 99% by weight, preferably 70 to 98% by weight, and an unsaturated carboxylic acid of 50 to 99% by weight.
Desirably it is present in an amount of 1% by weight, preferably 30-2% by weight. When the ethylene / unsaturated carboxylic acid copolymer contains a third component in addition to the ethylene component and the unsaturated carboxylic acid component, the third component is contained in an amount of 0 to 40% by weight, preferably 0 to 30% by weight. It is desirable that it exists. The ionomer is one in which at least a part of the carboxyl group in the ethylene / unsaturated carboxylic acid copolymer is neutralized with a transition metal cation. As transition metal cations for producing the present ionomer,
Monovalent or divalent cations such as Na ⁺ , K ⁺ , Mg ⁺⁺ , Ca ⁺⁺ , and Zn ⁺⁺ are preferable, and it is particularly preferable to use Zn ⁺⁺ . The degree of neutralization of this ionomer with the above transition metal cation is preferably in the range of 5 to 100%, particularly preferably in the range of 10 to 90%. Furthermore, the MFR of these ethylene / unsaturated carboxylic acid copolymers or ionomers (190 ° C., 2.
16 kg) is preferably 0.1 to 400 g / 10 min.

Component (e): Filler The filler of component (e) used in the present invention has a specific surface area of 37,000 cm ² / g or more, preferably 40,000 cm ² / g or more, and a length of substantially. 15μ
m or less, preferably 10 μm or less, and the average particle size is 0.8 to
3.0 μm, preferably 0.8 to 2.5 μm, and talc having an average aspect ratio of 5 or more, preferably 6 or more, an average diameter of 2 μm or less, preferably 1.5 μm or less, and an average aspect ratio of 5 or more; Preferably, 10 or more aluminum borate whiskers, potassium titanate whiskers, magnesium sulfate whiskers [magnesium oxysulfate whiskers MgSO ₄ .5Mg (O
H) 2 _· 3H 2 _O], is at least one filler selected from the titanium oxide whisker and the calcium carbonate whisker, calcium carbonate. Here, the “substantially” length of talc means that most talc particles are in this range. Talc is produced by, for example, crushing raw talc with an impact mill or a micron mill, further pulverizing it with a micron mill or a jet mill, and then classifying and adjusting it with a cyclone or a micron separator. Here, the gemstone is preferably made in China because of its low metal impurity content.
Furthermore, when talc having a specific surface area, a length, and an average aspect ratio outside the above range and having an average particle size exceeding the above range is used, the impact strength and coating appearance of a painted automobile member are inferior, while the average particle size is within the above range. If the diameter is smaller, it is difficult to disperse the talc, and the impact strength and the appearance of the coating deteriorate rather. Preferred examples of aluminum borate whiskers, potassium titanate whiskers, magnesium sulfate whiskers, titanium oxide whiskers, and calcium carbonate whiskers have an average diameter of 1.5 μm or less and an average aspect ratio of 10 or more. Those having an average diameter exceeding the above range are unsuitable because the appearance of the painted automobile member and the dimensional stability at high temperatures are poor. Among these fillers, talc, aluminum borate whisker, magnesium sulfate whisker [magnesium oxysulfate whisker MgSO _4.5 Mg (O
H) ₂ · 3H ₂₀ ] alone is preferred, and talc alone, talc and the above whiskers are more preferred, particularly talc alone, talc and aluminum borate whisker, talc and magnesium sulfate Use in combination with whiskers [magnesium oxysulfate whiskers MgSO ₄ .5Mg (OH) ₂ .3H ₂ O] is preferred. Here, the measurement of the average particle size is based on a liquid phase sedimentation type light transmission method. As a measuring device, there is, for example, an SA-CP type manufactured by Shimadzu Corporation, and the specific surface area is measured by an air transmission method. As an example of the measuring device, there is a model SS-100 manufactured by Shimadzu Corporation. The length and the aspect ratio are measured by a microscope or the like. These fillers may be surface-treated with a surfactant, a coupling agent or the like. The surface-treated filler is effective for further improving the strength and paintability of an automobile member.

(2) Amount ratio In the present invention, the mixing ratio of the above components (a) to (e) is particularly important. The component (a) is used in an amount of 30 to 70 parts by weight, preferably 55 to 65 parts by weight, per 100 parts by weight of the total amount of the component (b). Therefore, the component (b) is used in an amount of 70 to 30 parts by weight, preferably 45 to 35 parts by weight, per 100 parts by weight of the total amount of the component (a). If the amount of the component (a) exceeds the above range, that is, if the amount of the component (b) is less than the above range, the coating strength and the impact strength are poor,
If the amount of the component (a) is less than the above range, that is, if the amount of the component (b) exceeds the above range, the heat resistance rigidity and the surface hardness are deteriorated, which is not suitable. It is preferable that the above-mentioned compounding amount is in the preferable range because the coating performance and the mechanical strength become good. The compounding amount of the component (c) is the same as that of the component (a).
0.1 with respect to 100 parts by weight of the total amount of component and component (b)
To 25 parts by weight, preferably 0.1 to 18 parts by weight, particularly preferably 0.5 to 12 parts by weight. If it is less than the above range, the reproducibility of the paint adhesion is poor or the coating strength is low. On the other hand, exceeding the above range is not only uneconomical, but also causes bleed-out of the polymer, so that the coating strength is rather lowered. The compounding amount of the component (d) is a total amount of the component (a) and the component (b) of 10
0.1 to 25 parts by weight, preferably 0.1 to 25 parts by weight, based on 0 parts by weight.
If the amount is less than the above range, the coating strength is inferior. If the amount exceeds the above range, the heat resistance rigidity and the surface hardness are inferior. The amount of the component (e) is 0.01 to 7 parts by weight, preferably 0.1 to 6 parts by weight, particularly preferably 0 to 100 parts by weight based on the total amount of the components (a) and (b). 0.5 to 5 parts by weight. If the amount is less than the above range, the paintability of the painted automobile member is inferior. If the amount exceeds the above range, whitening due to damage of the painted automobile member occurs.

(3) Additional Components The above-mentioned resin composition molded article of the present invention usually contains a pigment for coloring, and further improves various other properties.
In addition to the above essential components (a) to (e), a softening agent for hydrocarbon rubber (average molecular weight 300 to 1,000)
0), various plasticizers, antioxidants, antistatic agents, flame retardants,
Various additives such as a dispersant can also be added. Further, each of the above (a) to (a) to the extent that the effects of the present invention are not significantly impaired.
Compounding materials such as various resins other than the component (e), various elastomers, various fillers such as glass fiber, glass balloon, and carbon fiber can be blended. In particular, the three components (f) to (h) described below are particularly preferable among the above additional components.

Component (f): Ethylene polymer The ethylene polymer used as an additional component in the resin composition molded article of the present invention includes low-density polyethylene (branched ethylene polymer), medium-density polyethylene, and high-density polyethylene. (Linear ethylene copolymer). Particularly preferred from the viewpoint of heat resistance are medium density and high density polyethylene (linear ethylene copolymer). The linear ethylene copolymer has a density of 0.915 to 0.9.
40 g / cm ³ , preferably 0.920 to 0.935 g /
a ^{cm 3, MFR (190 ℃,} 2.16kg) of 0.5
-200 g / 10 min, preferably 10-150 g / 10
Is a linear ethylene copolymer of ethylene and α-olefin. Here, as the α-olefin, butene-
1, hexene-1, 4-methylpentene-1, octene-1, and the like, and two or more of these may be used in combination. The production method of such a linear ethylene copolymer includes a pressure of 5 to 2,500 kg / cm ² and a temperature of 50 to 300.
Under the condition of ° C., using a catalyst such as a Ziegler type catalyst, a vanadium type catalyst, a Kaminsky type catalyst, ethylene and α-
A method of copolymerizing an olefin is employed. For example, a method described in JP-B-56-18132 is known. Here, the density outside the above-mentioned density range or the MF
If it is outside the R range, the coating performance of the automobile member is inferior, which is not preferable. The blending amount of the ethylene copolymer of the component (f) is such that the total amount of the component (a) and the component (b) is 100.
In general, 3 to 25 parts by weight, preferably 3 to 25 parts by weight based on parts by weight
20 parts by weight, particularly preferably 3 to 15 parts by weight.
If the compounding amount of the component (f) is less than the above range, the coating strength will be poor, and if it exceeds the above range, the balance of physical properties will be poor, which is inappropriate.

Component (g): Organotin compound The organotin compound used as an additional component in the molded article of the resin composition of the present invention is represented by the following formula. (R ¹ , R ² , R ³ , R ⁴ : a saturated hydrocarbon group having 1 to 12 carbon atoms, which may be the same or different, and preferably a saturated hydrocarbon group having 3 to 12 carbon atoms. Y ¹ , Y ² : fatty acids, maleic acid derivatives, mercaptans, mercapto acids, etc., which may be the same or different, preferably fatty acids, maleic acid derivatives X ¹ : oxygen atom, sulfur Atom, maleic acid, etc., preferably an oxidized atom, maleic acid, n: 0 or an integer of 1 to 30, preferably 0 or an integer of 1 to 25, particularly preferably 0 or 1 to 20.
Is an integer. Specific examples of these organotin compounds include monobutyl tin trimethyl malate, monobutyl tin trioctyl malate, dibutyl tin dilaurate, dibutyl tin trilaurate methyl malate, dibutyl tin dioleyl male. Rate, dibutyl tin dimethyl malate, dibutyl tin malate, dibutyl tin methoxymethyl malate, dibutyl tin dioctyl malate, dibutyl tin dioctyl thioglycolate, dibutyl tin dilauryl mercaptide And tribenzyl tin octyl malate, tribenzyl tin trimethyl malate and the like. These organotin compounds can be used alone or as a mixture of a plurality of types, and can be usually appropriately selected from commercially available ones. The amount of the organotin compound (g) is generally 0.01 to 5 parts by weight, preferably 0.05 to 5 parts by weight.
To 4 parts by weight, particularly preferably 0.1 to 3 parts by weight.
When the amount of the component (g) is less than the above range, the coating strength is inferior. When the amount exceeds the above range, bleed out occurs, so that the coating strength is rather lowered.

Component (h): Tertiary amine compound The tertiary amine compound used as an additional component in the molded article of the resin composition of the present invention is a low molecular compound having a tertiary amine structure. Refers to high molecular compounds. Low molecular weight compound having a tertiary amine structure The low molecular weight compound having a tertiary amine structure refers to a compound having a molecular weight of about 1,000 or less. Specific examples include triethylenediamine, dimethylaminopropylamine, diethylaminopropylamine, tetraguanidine, 1,8-diazabicyclo- (5,4,0) -7.
-Undecene, N, N-bis (2-hydroxyethyl)
Laurylamine and tetrakis (N-methyl-2,
2,6,6-tetramethyl-4-piperidyl) 1,2,2
3,4-butanetetracarboxylate and the like. These can be appropriately selected from commercially available ones.

Polymer Compounds Having Tertiary Amine Structure Polymer compounds having a tertiary amine structure include polymers having a molecular weight of 1,000 or more and which are liquid, semi-solid, or solid at room temperature. Examples of the polymer compound having a tertiary amine structure include a tertiary amino group-containing modified olefin polymer. The tertiary amino group-containing modified olefin polymer is, from a structural point of view, irregular or regular in a branched or linear carbon chain.
It refers to all compounds having a structure in which a tertiary amino group-containing unsaturated compound is copolymerized or a side chain having a tertiary amine structure is grafted. Specifically, the content of the tertiary amino group-containing unsaturated compound is 0.1 to 50% by weight, preferably 0.5 to 40% by weight, particularly preferably 1 to 40% by weight.
%, And the melt flow rate (MFR) measured in accordance with JIS-K6760 is 0.1 to
It is preferably 1,000 g / 10 min, particularly preferably 0.5 to 700 g / 10 min.

The tertiary amino group-containing modified olefin polymer can be produced by a known method using a tertiary amino group-containing unsaturated compound. For example, in the case of production by a high-pressure radical polymerization method, ethylene, a tertiary amino group-containing unsaturated compound and a radical polymerization initiator are mixed, for example, at a pressure of 1,000 to 3,000 atm and a temperature of 90 to 30.
In a reaction zone maintained at 0 ° C, the ratio of ethylene: unsaturated compound containing a tertiary amino group is from 1: 0.0001 to 1: 0.
The ethylene copolymer is continuously supplied so as to be 1 to obtain an ethylene copolymer at a conversion of 3 to 20%, and the copolymer is continuously removed from the reaction zone. In the case of production by the impregnation graft polymerization method, the tertiary amino group-containing unsaturated compound and the radical polymerization initiator to be reacted with the olefin polymer pellet are suspended in an aqueous solution, and the tertiary amino group-containing unsaturated compound is suspended. It is produced by impregnating an unsaturated compound and an initiator into an olefin polymer pellet, heating the pellet to the decomposition temperature of the initiator, causing a graft reaction in the pellet, and modifying the pellet.

Such a tertiary amino group-containing unsaturated compound is represented by the following formula. (R ⁵ : hydrogen or a saturated hydrocarbon group having 1 to 4 carbon atoms, preferably a hydrogen atom or a saturated hydrogen group having 1 to 2 carbon atoms. R ⁶ : saturation having 2 to 12 carbon atoms. A hydrocarbon group, preferably a saturated hydrocarbon group having 2 to 6 carbon atoms R ⁷ and R ⁸ : a saturated hydrocarbon group having 1 to 12 carbon atoms;
Preferably, it is a saturated hydrocarbon group having 1 to 6 carbon atoms, particularly preferably 1 to 3 carbon atoms. Here, R ⁷ and R ⁸ may be the same or different. X: an oxygen atom or -NR ⁹ -, a sulfur atom, preferably an oxygen atom, -NR ⁹ - a. R ^{9 is a} hydrogen atom or a saturated hydrocarbon group having 1 to 12 carbon atoms, preferably a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. Specific examples of these tertiary amine compounds include 2- (dimethylamino) ethyl acrylate, 2- (diethylamino) ethyl acrylate, 2- (dimethylamino) ethyl methacrylate, 2- (diethylamino) ethyl methacrylate, (T-butyl) amino] ethyl acrylate, 2- [di (t-butyl) amino] ethyl methacrylate, 3- (dimethylamino) -propylacrylamide, 3- (dimethylamino) -propylmethacrylamide and the like. it can.

The olefin-based monomer component when copolymerized with the tertiary amino group-containing unsaturated compound includes α-olefins such as ethylene, propylene and 1-butene. Particularly, ethylene is preferred. The olefin-based polymer component used as the backbone polymer when the tertiary amino group-containing unsaturated compound is grafted includes the olefin-based resin (component (a)) and the olefin-based elastomer described below ((e) -component). And the like. Of these, polyethylene-based resins, propylene-based resins and ethylene-based elastomers are preferred. Further, when producing a tertiary amino group-containing modified olefin polymer, monomer components that can be copolymerized with the tertiary amino group-containing unsaturated compound include methyl acrylate, ethyl acrylate, butyl acrylate, and methyl acrylate. Unsaturated carboxylic acid esters such as methacrylate; vinyl aromatic compounds such as styrene, α-methylstyrene and vinyltoluene; nitrile compounds such as acrylonitrile and methacrylonitrile; vinylpyridines such as 2-vinylpyridine and 4-vinylpyridine; Vinyl ethers such as methyl vinyl ether and 2-chloroethyl vinyl ether; halogenated vinyls such as vinyl chloride and vinyl bromide; vinyl esters such as vinyl acetate: acrylamide; and the like. Multi-component denaturation It is also possible to use as an olefin. And each of these modified polyolefins alone,
It can also be used as a mixture of plural kinds.
Among the tertiary amine compounds listed above, upon use,
A tertiary amino group-containing modified olefin polymer which is less likely to bleed out is preferred. The compounding amount of the tertiary amine compound is 0.01 to 20 parts by weight, preferably 0.0 to 20 parts by weight.
It is in the range of 5 to 18 parts by weight, particularly preferably 0.1 to 17 parts by weight. If it is less than the above range, the coating strength is inferior. These components (f) to (h) may be used alone, (f) and (g), (f) and (h), (g) and (h), or (f), (g), and (h). ) May be used to further improve the coating performance of automobile parts. As another component, a softening agent for hydrocarbon rubber plays an important role in controlling processability and flexibility. The softening agent for hydrocarbon rubber is
A mixture of an aromatic ring, a naphthene ring, and a paraffin chain, in which the number of carbon atoms in the paraffin chain accounts for 50% or more of the total carbon, is called a paraffinic system, in which the number of carbon atoms in the naphthene ring is 30 to 45%. Those are called naphthenics and those having an aromatic carbon number of more than 30% are called aromatics and are classified. Of these, paraffinic ones are preferred, and in the present invention, they are described as the component (i) in the examples.

[II] Production of Resin Composition Molded Product The above essential components (a) to (e) and, if necessary, additional components (f) to (h) are blended. The resulting resin composition is generally obtained by kneading using a conventional kneader such as a single-screw extruder, a twin-screw extruder, a Banbury mixer, a roll, a Brabender plastograph, or a kneader. It is preferable to select a kneading method for improving the dispersion of each component, and the kneading is generally performed using a twin-screw extruder. By molding using the resin composition thus obtained, a molded article as a soft automobile member can be obtained. The molding can be performed by a usual method. That is, any of molding methods such as injection molding, compression molding, and extrusion molding (sheet molding, blow molding) may be used, but among them, injection molding is preferable.

[III] Coating A coating material is directly applied to the surface of the molded article obtained as described above, and a coating film is formed directly on the surface. As a coating method, it can be carried out in a step obtained by removing the primer coating step from the conventional coating step. In addition, a plasma processing step performed to increase the adhesion of the coating film can be omitted. That is, the paint can be directly applied to the molded body that has not been subjected to the surface modification step. However, an auxiliary surface treatment such as a degreasing treatment may be performed before applying the paint. Such a degreasing treatment is a normal operation that is generally performed immediately before the application of a paint, and thereby involves inevitably attaching hand grit or a machine that adheres to the surface of the molded body in a process from molding of the molded body to before coating. Oil and the like can be removed by washing. Specifically, there is a cleaning method using an organic solvent liquid or its vapor, water, steam, an acid, an alkaline liquid, or a surfactant aqueous solution. Among these, there are cleaning methods using an organic solvent vapor, and water / hot water. Alternatively, washing using water or warm water to which an alkali solution or a neutral detergent is added, or alcohol washing is preferably used. As means for applying the paint, there are spraying by spraying, brushing, applying by a roller, etc., and any of these methods can be adopted. As the paint, generally used paint, for example, acrylic paint, epoxy paint, polyester paint, urethane paint,
Alkyd-based paints, melamine-based paints and the like can be mentioned. Among them, it is preferable to use an acrylic paint, a melamine paint, a polyester paint, or a urethane paint.

The coated soft automobile member of the present invention has a coating composition of generally 10 to 100 μm, preferably 15 to 70 μm.
m, and the coating film is firmly adhered with a peel strength of usually 500 g / cm or more, especially 700 to 2,000 g / cm, and of course, is extremely important in warm water resistance. In addition to being excellent, the weather resistance of unpainted parts exposed directly to sunlight is also high, so fenders, door panels, bumpers, spoilers, mudguards, side moldings, wheel caps, instrument panels,
It has high utility as an automotive component such as trim, console, and handle pad.

[0023]

The present invention will be described more specifically with reference to the following examples and comparative examples. The raw materials, coating method and evaluation method used here are as follows. (1) Raw materials (a) Component a-1: 14% by weight of a normal temperature xylene-soluble component having an ethylene content of 40% by weight, an ethylene content of the whole copolymer of 9% by weight and an MFR of 40 g / 10 minutes. Certain propylene / ethylene block copolymer a-2: contains 16% by weight of a normal temperature xylene-soluble component having an ethylene content of 30% by weight, and has an ethylene content of 7.5% by weight and an MFR of 10 g / 10 in the entire copolymer. Propylene / ethylene block copolymer a-3: containing 16% by weight of a room temperature xylene-soluble component having an ethylene content of 30% by weight, and having an ethylene content of 12% by weight and an MFR of 80 g / 10 min. Propylene / ethylene block copolymer a-4: having a flexural modulus of 13,000 kg / cm ² and M
Polypropylene having an FR of 25 g / 10 min a-5: an ethylene content of 13.8% by weight, JIS-K
Flexural modulus measured in accordance with 7203 is 13,000
kg / cm ² , a vinyltrimethoxysilane-graft-propylene-ethylene block copolymer (Mitsubishi Corporation) having an MFR of 11 g / 10 min and a silane compound content of 2.2% by weight as measured according to ASTM-D1238. Yuka Co., Ltd. trademark "Linklon XPM700B")

(B) Component b-1: ethylene-propylene copolymer rubber (EPM) having Mooney viscosity ML _{1 + 4} (100 ° C.) 47, propylene content 26% by weight

(C) Component c-1: A hydrogenated diene polymer having an iodine value of 1.0 (g / 100 g) and a hydroxyl value of 83.7 (KOH mg / g) (produced using butadiene as a main raw material). A product prepared by hydrogenating a diene polymer having a molecular weight of about 2,900 and a hydroxyl value of about 84.)

(D) Component d-1: Acrylic acid content is 20% by weight and MFR (1
90 ° C., 2.16 kg) is 300 g / 10 min. Ethylene-acrylic acid copolymer d-2: an ethylene-acrylic acid copolymer having an acrylic acid content of 15% by weight and an average molecular weight of 3,000

(E) Component e-1: specific surface area of 34,000 to 39,000 cm ²
/ G, talc having an average particle size of 1.5 to 2.0 μm e-2: an average diameter of 0.2 to 0.5 μm, and a fiber length of 1
0-20 μm potassium titanate whisker e-3: specific surface area of 10,000 to 11,500 cm ²
/ G, calcium carbonate having an average particle size of 0.15 to 0.30 μm

(F) Component f-1: density 0.958 g / cm ³ , MFR (190
2.16kg) 20g / 10min ethylene polymer

(G) Component g-1: dibutyl tin dilaurate

(H) Component h-1: Light stabilizer "Mark" manufactured by Adeka Argus
"LA62" is a compound having a structure represented by the following formula.

Embedded image (Wherein R ¹⁰ , R ¹¹ , R ¹² , and R ¹³ are represented by the following formulas or —C ₁₃ H
And it represents the _27, these ^{R 10, R 11, R 12} , R 13
At least one of which is N-methyl-2,2,6,6
-Tetramethyl-4-piperidyl group, the remainder being a saturated hydrocarbon group having 13 carbon atoms. ) H-2: 2- obtained by high-pressure radical polymerization method
(Dimethylamino) ethyl methacrylate content of 30
% By weight, MFR measured according to JIS-K6760
Is an ethylene-2- (dimethylamino) ethyl methacrylate copolymer of 2 g / 10 min.

H-3: A graft copolymer obtained by grafting 2- (dimethylamino) ethyl methacrylate and styrene onto polyethylene as a backbone polymer obtained by the synthesis of EDMA (2) by the following impregnation graft polymerization method: -(Dimethylamino) ethyl methacrylate content: 15% by weight, styrene content: 25% by weight, JIS-
It is a graft copolymer having an MFR measured according to K6760 and showing a physical property value of 2 g / 10 minutes. Synthesis of h-3 by impregnated graft polymerization In an autoclave with a capacity of 10 liters, JIS-K67
60 g of linear low density polyethylene pellets having an MFR of 100 g / 10 min, measured in accordance with No. 60, 270 g of 2- (dimethylamino) ethyl methacrylate, 450 g of styrene, 6.5 g of benzoyl peroxide, and calcium phosphate [Ca ₃ (PO ₄ ) ₂ ] 21
g was suspended in 4 liters of water. Next, the temperature of the suspension was maintained at 50 ° C. for 3 hours, and the 2- (dimethylamino) ethyl methacrylate, styrene, and benzoyl peroxide were impregnated into the polyethylene pellets. Thereafter, the reaction was carried out while gradually increasing the temperature to 94 ° C. over 8 hours. After completion of the reaction, the obtained pellet was washed with water, and water was removed with a centrifugal separator.
And dried under reduced pressure for 12 hours. 2 of the obtained polymer
-(Dimethylamino) ethyl methacrylate content is 15% by weight, styrene content is 25% by weight, MFR is 2%
g / 10 minutes.

(I) Component i-1: Paraffin oil having an average molecular weight of 746 and a ring analysis of 0%.

(2) Coating method (Pre-treatment, baking treatment) After the formed flat plate was subjected to the following pre-treatment, that is, degreasing treatment with trichloroethane vapor (TCE treatment) for 20 seconds and no washing (no treatment), respectively. The paint was applied using an air gun. After the completion of baking and drying, the coating was allowed to stand at room temperature for 48 hours to conduct a coating test. (Coating) The coating was performed using a commercially available polyester urethane coating. (Coating) Each coating material was prepared and spray-coated using an air spray gun so that the coating film thickness was about 30 μm and about 100 μm.

(3) Evaluation [Evaluation of Mechanical Strength] (Flexural Modulus) A molded sample was measured in accordance with JIS-K7203. The measurement temperature is 23 ° C. (Scratch test) The test sheet was rubbed with a 100-yen coin, and the trace was visually observed to confirm the whitening condition due to the scratch. [Evaluation of Paint Adhesion] (Cross-cut test) 100 cross-cuts are formed by drawing parallel lines of 11 lines each vertically and horizontally at 1 mm intervals on the surface of a test piece coated to a thickness of about 30 μm using a single-edged razor. A cellophane adhesive tape (JIS-Z1522) is sufficiently pressed on top of it,
At 0 °, the sheet was peeled off at a stretch, the state of the portion surrounded by the grids was observed, and the number of grids not peeled was recorded. (Peel strength (peel strength)) The surface of a test piece coated to a thickness of about 100 μm was cut straight with a single-edge razor with a width of 1 cm using a razor. (Temperature resistance test) After immersion in warm water of 40 ° C. for 240 hours, evaluation was made by a grid test.

[Examples 1 to 22 and Comparative Examples 1 to 9] (a) Component (powder), (b) component, (c) component, (d)
Component, component (e), component (f), component (g), component (h) and component (i) were blended in the proportions shown in Tables 1 to 6, and tris (2,4-di-t- Butylphenyl) phosphite and 3,9-bis [2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1.dimethylethyl] -2,4,8 ,
0.1 part by weight of 10-tetraoxaspiro [5.5] undecane per 100 parts by weight of components (a) to (e) in total, 3.0 parts by weight of a carbon black masterbatch, and oleic acid The amide was compounded in 0.3 parts by weight each and mixed well with a high-speed mixer. Thereafter, the mixture is kneaded and granulated at a temperature of 210 ° C. using a high-speed twin-screw extruder, and the obtained colored pellets are supplied to a screw in-line type injection molding machine, and a sheet (1) for evaluating paintability and weather resistance is obtained.
(00 mm × 100 mm × 3 mm) and a specimen for evaluating physical properties were molded at 210 ° C. Tables 1 to 6 show the evaluation results.

[0036]

[Table 1]

[0037]

[Table 2]

[0038]

[Table 3]

[0039]

[Table 4]

[0040]

[Table 5]

[0041]

[Table 6]

[0042]

According to the present invention, the painted soft automobile member is
Unlike automotive parts molded with conventional propylene-based soft resin, the paint is applied directly to the surface of the molded body without any modification treatment, simplifying the painting process, improving the working environment, and reducing costs. The obtained product has practically sufficient paint adhesion performance including mechanical strength and hot water resistance, and can be used for bumpers, spoilers, mudguards, side moldings, wheel caps, and instruments. It is an excellent material that can be used as an automobile member such as a panel.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification code FI C08L 53/00 C08L 53/00 C09D 109/00 C09D 109/00 125/10 125/10 (72) Inventor Sadao Kitagawa Mie No. 1, Toho-cho, Yokkaichi-shi, Prefecture Mitsubishi Yuka Corporation Yokkaichi Research Institute (72) Inventor Yuta Kumano 1, Toho-cho, Yokkaichi, Mie Prefecture Mitsubishi Yuka Corporation Yokkaichi Research Institute (56) References 3-277636 (JP, A) JP-A-4-198232 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B05D 7/02 B05D 7/24 302 B60R 19/03 C08K 7 / 04 C08L 23/26 C08L 53/00 C09D 109/00 C09D 125/10

Claims (2)

(57) [Claims] (1) It comprises the following components (a) to (e),
Flexural modulus (JIS-6703) of 10,000 kg / cm
A coated soft automobile member, characterized in that a coating film is directly formed on the surface of a resin composition molded article having a size of ² or less. Component (a): contains 4 to 30% by weight of a room temperature xylene-soluble component having an ethylene content of 20 to 70% by weight, and has an MFR of 1 to 200 g / 10 minutes and an ethylene content of 3
30 to 70 parts by weight of a propylene / ethylene block copolymer in an amount of from 21 to 21% by weight, and component (b): selected from an ethylene-based elastomer, a hydrogenated styrene / butadiene block copolymer and a hydrogenated styrene / isoprene block copolymer. At least one elastomer obtained: 70 to 30 parts by weight, based on 100 parts by weight of the total of components (a) and (b), component (c): a diene polymer having a hydroxyl group at a terminal or hydrogenation thereof. Product: 0.1 to 25 parts by weight, (d) Component: a copolymer of ethylene and an unsaturated compound containing a carboxyl group (including an acid anhydride group) or a copolymer containing ethylene and a carboxyl group (including an acid anhydride group) At least one selected from ionomers in which at least a part of the carboxyl groups in the copolymer with a saturated compound has been neutralized with a transition metal cation. : 0.1-25 parts by weight, (e) component: a specific surface area of 37,000cm ² / g or more, is substantially 15μm or less in length, the average particle diameter of 0.8 to 3.0
talc having an average aspect ratio of 5 or more, aluminum borate whisker having an average diameter of 2 μm or less and an average aspect ratio of 5 or more, whisker of potassium titanate, and whisker of magnesium sulfate [magnesium oxysulfate whisker MgSO ₄ .5Mg (OH)
₂ · 3H ₂ O], the titanium oxide whiskers, also a kind of filler less selected from the calcium whiskers and calcium carbonate: 0.01 to 7 parts by weight, 2. The coated soft automobile member according to claim 1, wherein the resin composition molded article further comprises at least one of the following components (f) to (h). Component (f): ethylene polymer: 3 to 25 parts by weight Component (g): organotin compound: 0.01 to 5 parts by weight Component (h): tertiary amine compound: 0.01 to 20 parts by weight