KR20160035645A - Coating composition for an vehicle parts, painting method for vehicle parts and vehicle parts using the same - Google Patents

Abstract

The present invention relates to a coating composition for vehicle parts, and a coating method for vehicle parts and vehicle parts using the same. In an embodiment, the coating composition for vehicle parts comprises: a main agent containing 50-70 parts by weight of an acryl polyol resin, 0.1-0.5 parts by weight of an adhesion enhancer, 0.01-1.0 parts by weight of a pigment, 0.1-1.5 parts by weight of a reaction catalyst, 0.5-8.0 parts by weight of additives and 20-40 parts by weight of a solvent; and 10-30 parts by weight of a curing agent containing a resin for a curing agent and a solvent for a curing agent. The acryl polyol resin is a blend of a non-reactive acryl polyol resin and a reactive acryl polyol resin at a weight ratio of 1:1.5-1.5:1, and the resin for a curing agent is used in an amount of 5-20 parts by weight based on 100 parts by weight of the main agent, and the solvent for curing agent is used in an amount of 5-15 parts by weight based on 100 parts by weight of the main agent. According to the present invention, it is possible to realize a beautiful and light color while maintaining a metallic texture of chrome plating, to control various designs, colors and gloss, to ensure the reliability required for an interior part for vehicles so that the part may have a desired function and high quality, to improve the product value of an interior part of vehicles, to provide sun cream resistance, scratch resistance and wear resistance, and to simplify the conventional secondary and tertiary coating systems into a mono-coating system, thereby reducing the cost and total processing cost.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating composition for vehicle parts,

TECHNICAL FIELD The present invention relates to a coating composition for automobile parts, a method for coating a vehicle part using the same, and a vehicle part. More specifically, the present invention relates to a paint composition for vehicle parts, which can be applied in various colors while maintaining a beautiful feel of metal feeling and is excellent in anti-sunmking property, scratch resistance and abrasion resistance, Methods and vehicle components.

In recent years, demand for components with various designs and functions has been rapidly increasing as a result of the upgrading of vehicles such as automobiles. Especially, it is increasingly applied to enhance the quality of parts such as chrome-plated interior parts of vehicle parts.

However, in order to realize various colors by painting on the chromium-plated surface having the adhesive property, special functions necessary for each part should be added with the basic property of adhesion to the plating layer.

In order to impart adhesion properties to the plating layer, a coating system using a chlorinated polyolefin as a main resin or a coating system of a multi-layer structure in which intermediate and upper coatings are coated to satisfy other required properties is applied.

On the other hand, paint such as a radiator grill is applied to exterior plating parts to decorate with only chrome, and the coating design is centered on chipping resistance and water resistance. In order to satisfy adhesion and chipping resistance, 2 ~ 3coat ( Under, middle, and upper) coating system.

1 is a sectional view of a vehicle part (bumper) 200 painted by a conventional painting method, and is an example of 2 to 3 coats. Referring to FIG. 1, a primer coating layer 12 is formed on the surface of a polyol based substrate 10 for a vehicle component, and then a base coating layer 12 is formed on the surface of the primer coating layer 12, Coating 3 is formed by forming a base coating layer 22 on the base coat layer 22 and forming a clear coat layer 30 for protecting the base coat layer 22 and providing gloss and linearity, - Baking (3C-1B) system is applied.

However, with such a 2 to 3Coat multi-layer coating system, the cost of coating is increased, and chrome plating is partially applied while hue and low transparency hiding are applied. There is a problem of being hidden.

Related technologies include KR10-2010-0042523, KR10-2006-0000708, and the like.

An object of the present invention is to provide a chrome-plated metal feeling, which is beautiful and has a hint of color, can be adjusted in various designs, colors and glosses, It is a coating composition for automobile parts which has reduced the cost and overall process cost by simplifying the existing 2nd and 3rd coating system with Mono coating system because it improves the merchantability of parts and has excellent anti-sun cream, scratch resistance and abrasion resistance. .

Another object of the present invention is to provide a method of painting a vehicle part using the above-mentioned paint composition for vehicle parts.

It is still another object of the present invention to provide a vehicle part painted by the vehicle parts painting method.

The above and other objects of the present invention can be achieved by the present invention described below.

One aspect of the present invention relates to a process for the preparation of an adhesive composition comprising 50 to 70 parts by weight of an acrylic polyol resin, 0.1 to 0.5 parts by weight of an adhesion promoter, 0.01 to 1.0 parts by weight of a pigment, 0.1 to 1.5 parts by weight of a reaction catalyst, , 20 to 40 parts by weight of a solvent; And 10 to 30 parts by weight of a curing agent comprising a curing agent and a curing agent, wherein the acrylic polyol resin is a mixture of a non-reactive acrylic polyol resin and a reactive acrylic polyol resin in a ratio of 1: 1.5 to 1.5: 1 And the curing resin is contained in an amount of 5 to 20 parts by weight based on 100 parts by weight of the resin and 5 to 15 parts by weight with respect to 100 parts by weight of the resin composition .

In an embodiment, the acrylic polyol resin is a non-reactive acrylic polyol resin having a glass transition temperature (Tg) of 50 to 60 占 폚, a solid content of 40 to 60% and a weight average molecular weight of 25,000 to 40,000 g / mol; And a reactive acrylic polyol resin having a solid content of 60 to 80%, a hydroxyl value of 3 to 5%, and a weight average molecular weight of 9,000 to 18,000 g / mol.

In an embodiment, the adhesion promoter may comprise a phosphate based adhesion promoter.

Another aspect of the present invention is a method of manufacturing a chromium-plated vehicle component, comprising the steps of: preparing a chromium-plated vehicle component substrate; Coating a chromium-plated surface of the substrate with the coating composition for a vehicle component to form a mono coating layer; And curing the mono coating layer.

In an embodiment, before coating the coating composition, pre-treating the chrome plated surface with isopropyl alcohol.

In an embodiment, the curing may be carried out at 70 to 90 占 폚 for 20 to 50 minutes.

Another aspect of the present invention is a chrome plated vehicle component; And a mono coating layer formed on a chromium-plated surface of the vehicle component, wherein the mono coating layer relates to a vehicle component formed from the coating composition for a vehicle component.

In an embodiment, the mono coating layer may have a thickness of 10 mu m to 20 mu m.

In an embodiment, the vehicle component may be a bumper, a side seal molding, a side garnish, or a side protector.

The coating composition for vehicle parts according to the present invention can provide a beautiful, delicate color while maintaining the metallic feel of chrome plating, and can control various designs, colors and glosses, and secures the reliability required for automobile interior parts, Simultaneous implementation and improvement of the merchantability of automotive interior parts, excellent anti-sun cream property, scratch resistance and abrasion resistance, and simplification of existing 2nd and 3rd coating coating system into mono coating system to realize cost reduction and reduction of total process cost .

1 is a cross-sectional view of a painted vehicle part according to one embodiment of the present invention.
2 is a cross-sectional view of a vehicle part painted by a conventional painting method.

Embodiments of the present application will now be described in more detail with reference to the accompanying drawings. However, the techniques disclosed in the present application are not limited to the embodiments described herein but may be embodied in other forms. It should be understood, however, that the embodiments disclosed herein are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the width, thickness, and the like of the components are enlarged in order to clearly illustrate the components of each device.

In addition, although only a part of the components is shown for convenience of explanation, those skilled in the art can easily grasp the rest of the components. It is to be understood that when an element is described above as being located above or below another element, it is to be understood that the element may be directly on or under another element, It means that it can be done. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. In the drawings, the same reference numerals denote substantially the same elements.

Also, the singular " include " should be understood to include plural representations, unless the context clearly dictates otherwise, and the terms & Parts or combinations thereof, and does not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

Further, in carrying out the method or the manufacturing method, the respective steps of the method may take place differently from the stated order unless clearly specified in the context. That is, each process may occur in the same order as described, may be performed substantially concurrently, or may be performed in the opposite order.

Hereinafter, the present invention will be described in more detail.

Paint composition for vehicle parts

One aspect of the present invention relates to a coating composition for vehicle parts. In one embodiment, the coating composition for vehicle parts comprises a subject comprising an acrylic polyol resin, an adhesion promoter, a pigment, a reaction catalyst, an additive, and a solvent; And a curing agent including a resin for a curing agent and a solvent for a curing agent.

Hereinafter, components constituting the present invention will be described in detail.

subject

The subject of the coating composition for vehicle parts according to the present invention is characterized in that 50 to 70 parts by weight of an acrylic polyol resin, 0.1 to 0.5 parts by weight of an adhesion promoter, 0.01 to 1.0 parts by weight of a pigment, 0.1 to 1.5 parts by weight, 0.5 to 8.0 parts by weight of an additive and 20 to 40 parts by weight of a solvent. When the coating composition of the present invention is applied to the chromium-plated surface of the substrate in the above-mentioned content range, the adhesion force is increased and the anti-sunmatic property, scratch resistance and abrasion resistance can be excellent.

Acrylic polyol resin

The acrylic polyol resin may be included for the purpose of increasing the surface tension of the coating composition for vehicle parts and the base material and increasing the adhesion with the plating layer by alleviating the urethane curing shrinkage.

In the present invention, the above-mentioned " acrylic polyol resin " may be mixed with a non-reactive acrylic polyol resin and a reactive acrylic polyol resin at a weight ratio of 1: 1.5 to 1.5: 1 based on 100% by weight of the total acrylic polyol resin. It is possible to prevent deterioration of the appearance of the coating film (coating layer) of the base material for automobile parts when mixed in the above-mentioned range and to secure the required physical properties of the plating layer.

The above-mentioned " non-reactive acrylic polyol resin " is an acrylic polyol resin having a high weight-average molecular weight and excellent adhesion to a plating layer, and has a structure represented by the following formula (1). The vinyl monomer is subjected to radical polymerization in a solution using a thermal decomposition initiator Can be manufactured:

[Chemical Formula 1]

(Wherein n is an integer of 55 to 89)

Examples of the acrylic or vinyl-based monomer used in the synthesis of the non-reactive acrylic polyol resin include non-functional monomers such as methyl acrylate, ethyl acrylate, isopropyl acrylate, N-butyl acrylate, ethylhexyl acrylate, Acrylate, methacrylic acid and the like, which are carboxyl functional monomer, and vinyl monomers such as styrene, acrylonitrile, methacrylonitrile, methacrylonitrile, methacrylonitrile, Vinyl toluene, acrylonitrile, and vinyl acetate. These may be used alone or in combination.

At this time, it is preferable that the glass transition temperature (Tg) during the synthesis is controlled within the range of 0 to 60 ° C. In the above range, it is possible to prevent the coating film from being damaged or brittle by the external impact and deteriorating the chipping resistance. In addition, a radical reaction initiator including a peroxide and an azo compound may be used in the polymerization reaction through the synthesis, and preferably 0.5 to 5 parts by weight may be used. The residual unreacted vinyl monomer can be avoided in the above range, and the increase in the price can be eliminated.

More specifically, the non-reactive acrylic polyol resin may be prepared as follows. First, a solvent such as toluene, xylene, or ketones is introduced into a four-necked flask equipped with a stirrer, a condenser and a thermometer, and the methacrylic monomer or the acrylic monomer and the initiator are heated at a temperature of 100 to 130 Lt; 0 > C for 2 to 5 hours. Then, it is held for 0.5 to 1 hour, the additional initiator is diluted with the solvent, and the solution is added dropwise for 0.5 to 1 hour. Followed by additional initiator dropping followed by 2 to 3 hours at the same temperature followed by cooling.

The non-reactive acrylic polyol resin may have a glass transition temperature (Tg) of 50 to 60 ° C, a solid content of 40 to 60%, and a weight average molecular weight of 25,000 to 40,000 g / mol. In the above range, the adhesion to the plating layer is excellent, and since the resin does not contain a hydroxyl group, it does not participate in the reaction, and the urethane hardening shrinkage is alleviated, thereby further improving the adhesion.

The non-reactive acrylic polyol resin is one of two kinds of acrylic polyol resins. The non-reactive acrylic polyol resin may be mixed with the reactive acrylic polyol resin to be described later in an amount of 1: 1.5 to 1.5: 1 by weight based on 100% have. In the above range, there is an advantage that the deterioration of the appearance of the coating film (coating layer) of the base material for vehicle parts can be prevented and the required physical properties of the coating film can be secured.

The above-mentioned " reactive acrylic polyol resin " is an acrylic polyol resin having a high hydroxyl group and excellent in reactivity and has a structure represented by the following formula (2), and improves the chemical resistance, moisture resistance and the like by improving crosslink density with a curing agent Which can be prepared by radical polymerizing a vinyl monomer in solution using a thermal decomposition initiator:

(2)

(Wherein n is an integer of 14 to 50)

Examples of the acrylic or vinyl monomer used for synthesizing the reactive acrylic polyol resin include non-functional monomers such as methyl acrylate, ethyl acrylate, isopropyl acrylate, N-butyl acrylate, ethylhexyl acrylate, methyl methacrylate , Ethyl methacrylate, butyl methacrylate, and isobutyl methacrylate. Examples of the carboxyl functional monomer include acrylic acid and methacrylic acid. Examples of the hydroxyl monomer include 2-hydroxy methacrylate, hydroxypropyl methacrylate, Acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl acrylate and the like. In addition, vinyl monomers such as styrene, vinyl toluene, acrylonitrile and vinyl acetate, Can be mixed and used.

At this time, it is preferable that the glass transition temperature (Tg) during the synthesis is controlled within the range of 0 to 60 ° C. In the above range, it is possible to prevent the coating film from being damaged or brittle by the external impact and deteriorating the chipping resistance. In addition, a radical reaction initiator including a peroxide and an azo compound may be used in the polymerization reaction through the synthesis, and preferably 0.5 to 5 parts by weight may be used. The residual unreacted vinyl monomer can be avoided in the above range, and the increase in the price can be eliminated.

More specifically, the reactive acrylic polyol resin may be prepared as follows. First, a solvent such as toluene, xylene and ketones is introduced into a four-necked flask equipped with a stirrer, a condenser and a thermometer, and the methacrylic monomer, the acrylic monomer and the initiator are heated at 120 to 150 ° C At a temperature of 3 to 6 hours. Then, it is held for 0.5 to 1 hour, the additional initiator is diluted with the solvent, and the solution is added dropwise for 0.5 to 1 hour. Followed by additional initiator dropping followed by 2 to 3 hours at the same temperature followed by cooling.

The reactive acrylic polyol resin may have a weight average molecular weight of 9,000 to 18,000, a hydroxyl content of 3 to 5% and a solid content of 60 to 80%. It has a high hydroxyl group in the above range and has an improved crosslinking density and excellent physical properties such as chemical resistance and can prevent deterioration of adhesion with a plating layer due to shrinkage of curing after crosslinking through control of hydroxyl groups.

Adhesion promoter

The adhesion promoter is used in an appropriate amount in the metallic paint to improve the adhesion of the coating composition, and through this, the adhesion enhancing effect and the silver oxidation prevention can be realized.

In one embodiment, the adhesion promoting agent may be a phosphoric acid adhesion promoting agent for improving the adhesion of the chromium-plated surface and the paint. The phosphoric acid-based adhesion promoter has a number average molecular weight of 500 to 1,000, and has an oxide and a hydroxy oxide group (Group), which can increase the adhesion between the paint and the surface of the chromium material. Preferably, a hydroxy / carboxy-functional phosphate ester can be used. The adhesion promoter is transparently diluted in an alcohol solvent. When diluted with a ketone, an acetate, a hydrocarbon, or the like, paint turbidity and seeding may occur.

The adhesion promoter may be used in an amount of 0.1 to 0.5 parts by weight, preferably 0.2 to 0.4 parts by weight based on 100 parts by weight of the whole base material of the paint composition for vehicle parts. If the adhesion promoting agent is less than 0.1 parts by weight, the effect of increasing the adhesion may be insufficient. If the adhesion promoting agent is more than 0.5 parts by weight, the water resistance may be deteriorated, which may cause blistering or haze of the coating film.

Pigment

The pigment may be included in the vehicle component coating composition of the present invention for mixing with an acrylic polyol resin to express a desired color. In particular, in the present invention, the pigment may be nano-dispersed in a size of 150 to 300 nm to enhance transparency and realize various colors while maintaining a plating feeling.

The pigment provides color, especially colored, to the vehicle component, which includes pigments such as oil / inorganic colored pigments, Al-paste, pearl, extender pigments and the like commonly used in vehicle parts These may be used alone or in combination of two or more. Specific examples thereof include, but are not limited to, red series, yellow / orange series, blue series, black series, white series, pearl and metallic series. In addition, the pigments may have an adverse effect on the physical properties of the coating layer when they are applied to vehicle parts in excessive use, and their usage should be controlled.

In one embodiment, the pigment may be included in the paint composition for vehicle parts in an amount of 0.01 to 1.0 part by weight based on 100 parts by weight of the whole of the base. Preferably 0.05 to 0.8 part by weight. More preferably 0.1 to 0.5 parts by weight. When the pigment is contained in an amount of less than 0.01 part by weight, the hue of the color may be insignificant and the appearance may be deteriorated. When the pigment is used in an amount exceeding 1.0 part by weight, the chrome plating may be concealed.

Reaction catalyst

The reaction catalyst may improve the reaction rate of the curing agent with the subject by using a urethane reaction catalyst. The reaction catalyst may be included in an amount of 0.1 to 1.5 parts by weight based on 100 parts by weight of the total of the main components of the paint composition for vehicle parts. When the amount of the reaction catalyst is less than 0.1 parts by weight, the coating composition is insufficiently cured and the effect of improving the chemical resistance is insignificant. When the amount is more than 1.5 parts by weight, the visible time may be shortened.

additive

The additive may be added to the coating composition in a predetermined amount range to realize a further effect for improving the wettability and leveling property in coating.

In one embodiment, the additive may be included in an amount of 0.5 to 8.0 parts by weight based on 100 parts by weight of the total amount of the paint composition for vehicle parts. Preferably 1 to 5 parts by weight. More preferably 2 to 4 parts by weight. If the amount of the additive is less than 0.5 parts by weight, the smoothness and light resistance of the coating composition may deteriorate. If the amount of the additive exceeds 8 parts by weight, the physical properties of the coating composition may deteriorate.

In one embodiment, additives commonly included in the coating compositions for vehicle parts can be used. For example, the additive may include at least one of wetting agent, defoamer, light stabilizer, adhesion promoter, surface modifier, anti-stain agent, softener and thickener.

The wetting additive is intended to improve the wettability and leveling property of the coating film during coating by controlling the surface tension of the coating composition for vehicle parts. In order to improve the wettability upon coating and the leveling property of the coating film, a polydimethylsiloxane- . The wetting additive may be included in an amount of 0.5 to 5 parts by weight based on 100 parts by weight of the total amount of the additive. The wettability and leveling property of the coating film may be improved in the above range.

The antifoaming agent is a mixture of a hydrophilic and a polysiloxane, and can act to enhance the appearance of the coating film by breaking bubbles generated during coating. The antifoaming agent may be included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the total amount of the additive. In the above range, bubble formation during coating can be suppressed and the appearance can be improved.

The light stabilizer has the effect of enhancing the weatherability of the coating film as an ultraviolet absorber. In the present invention, UVA and HALS were used in combination. The light stabilizer may be included in an amount of 1.0 to 5.0 parts by weight based on 100 parts by weight of the total additive. Within the above range, there may be an effect of improving the weatherability of the coating film.

The surface conditioner is intended to improve the wettability and leveling property of the coating film during coating by controlling the surface tension of the coating composition for vehicle parts. The surface modifier may be included in an amount of 0.1 to 5.0 parts by weight based on 100 parts by weight of the total additive. Within the above range, there may be an effect of improving the wettability and leveling property of the coating film.

The anti-staining agent is intended to suppress the occurrence of stains during the formation of a coating film through uniform arrangement of pigments, particularly silver particles, upon coating. The anti-staining agent may be added in an amount of 0.1 to 10 parts by weight, for example, 0.1 to 1 part by weight, or 1 to 10 parts by weight based on 100 parts by weight of the total amount of the additive. Within the above range, there may be an effect of suppressing the occurrence of stains at the time of coating film formation.

The softening agent may be included in an amount of 0.5 to 5 parts by weight based on 100 parts by weight of the total amount of the additive. Within the above range, the occurrence of cracks in the dry film is mitigated to improve the impact resistance and bending resistance.

solvent

The solvent may be included for the purpose of improving the smoothness and coating workability of the coating layer (coating layer) by adjusting the viscosity of the coating composition for vehicle parts, facilitating the coating operation, and adjusting the volatilization rate of the solvent.

Examples of the solvent include an ester system; Ketone type; Or a mixture thereof. Preferably, an ester system can be used. For example, ethyl acetate and butyl acetate can be used. These may be used singly or in combination of two or more, but are not limited thereto. When the solvent is used, the evaporation rate is low and the spreadability of the pigment can be improved, and workability and adhesion of the paint composition for vehicle parts can be improved.

In one embodiment, the solvent may be varied depending on the thickness of the coating film (coating layer) required and the method of forming the coating film, but it may be 20 to 40 parts by weight based on 100 parts by weight of the entirety of the main component of the vehicle component coating composition. Preferably 25 to 35 parts by weight. More preferably from 28 to 32 parts by weight. If the amount of the solvent is less than 20 parts by weight, the smoothness and workability of the coating composition may be deteriorated. If the amount of the solvent is more than 40 parts by weight, color unevenness and flowability of the coating composition may occur.

Hardener

The curing agent of the coating composition for vehicle parts according to the present invention may be used in an amount of 10 to 30 parts by weight based on 100 parts by weight of the subject. When the amount of the curing agent is less than 10 parts by weight, there is a problem that the anti-sunmatic property, scratch resistance and abrasion resistance are deteriorated, and when it is more than 30 parts by weight, adhesiveness and heat resistance are weakened.

Resin for hardener

As the resin for the curing agent, a non-yellowing type isocyanate trimer may be used. The resin for the curing agent can maintain the hardness and the chipping resistance of the urethane coating film in the biuret type among the isocyanate trimer. When isocyanurate type resin is used in the isocyanate type trimer, it can increase the hardness of the coating film and improve the thermal stability and chemical stability compared to the biuret type. However, since the coating film becomes stronger, the chipping resistance may be deteriorated. One or more of these can be used, and the amount of the used is suitably 5 to 20 parts by weight in order to react with 1: 0.8 to 1: 1.2 to the main resin equivalent. Preferably, a hexamethylene diisocyanate trimer system having excellent non-yellowing and weathering properties can be used. It is possible to prevent the problem that the crosslinking density is lowered in the above range and the coating film hardness is lowered and the water resistance is deteriorated due to the residual OH groups of the polyol resin and that the crosslinking density is increased to increase the hardness of the coating film, Can be prevented.

The resin for the curing agent may include 5 to 20 parts by weight based on 100 parts by weight of the whole of the main component of the coating composition for vehicle parts. When the amount of the resin for curing agent is less than 5 parts by weight, there is a problem that the anti-sunmatic property, scratch resistance and abrasion resistance are deteriorated, and when it exceeds 20 parts by weight, adhesion and heat resistance are weakened.

Solvent for hardener

The solvent for the curing agent may be selected from aliphatic, alicyclic and aromatic solvents containing 2 to 10 carbon atoms. Also, the solvent for the curing agent may include 5 to 15 parts by weight based on 100 parts by weight of the whole of the main component of the coating composition for vehicle parts. If the amount of the solvent for the curing agent is less than 5 parts by weight, the smoothness and workability of the coating composition may be deteriorated. If the amount is more than 15 parts by weight, color unevenness and flowability of the coating composition may occur.

Vehicle parts painting method

Another aspect of the present invention relates to a vehicle part paint method using a paint composition for vehicle parts. In one embodiment, the vehicle component painting method comprises the steps of: preparing a chromium-plated vehicle component substrate; Coating a chromium-plated surface of the substrate with the coating composition for a vehicle component described above to form a mono coating layer; And curing the mono coating layer.

In the vehicle component coating method, the coating composition for a vehicle component is applied to the surface of the substrate for a vehicle component without primer treatment, even when the existing primer coating step is not included, Can be achieved at the same time.

In one embodiment, the base for a vehicle component may be a polyolefin-based material. For example, it may be a plastic substrate such as ABS resin, polycarbonate, or polypropylene, or a metal substrate such as steel, but is not limited thereto.

The coating (coating) of the coating composition for vehicle parts can be carried out in a usual manner. For example, it is possible to supply the paint composition for a vehicle part to a paint gun of a paint robot and paint each time the vehicle part passes through it. As the chromium plating treatment method, a known plating treatment method may be used.

The coating was performed by mixing the subject of the coating composition according to the present invention with a curing agent in a ratio of 4.0: 1.0 to 1.0: 5.0% by weight and using a diluting solvent to make a coating viscosity of 13.0 to 15.0 (Ford Cup # 4) can do.

In one embodiment, the mono coating layer may be formed on the chromium-plated surface of the vehicle component substrate to a thickness of 10 to 20 占 퐉, preferably 12 to 18 占 퐉, more preferably 14 to 16 占 퐉 have. When formed in the above-mentioned range, it is excellent in adhesion with the surface of the substrate for a vehicle component, has excellent color representation and physical properties, and can prevent appearance defects and the like.

In one embodiment, the curing (baking) may be performed using hot air at 70 to 90 ° C for 20 to 50 minutes, preferably 75 to 85 ° C for 30 to 40 minutes. The drying can be easily carried out within the above-mentioned range, so that defective appearance can be prevented.

Further, the method may further include pretreating the chromium-plated surface with isopropyl alcohol before coating the coating composition to improve the adhesion of the coating composition for vehicle parts and to improve the appearance after painting. The pretreatment means cleaning by a whipping method using isopropyl alcohol (IPA) or the like by a conventional method.

Vehicle parts

Another aspect of the present invention relates to a vehicle component by the vehicle component painting method. In one embodiment, the vehicle component comprises a chromed vehicle component; And a mono-coating layer formed on a chromium-plated surface of the vehicle component, wherein the mono-coating layer can be formed from the coating composition for vehicle parts.

1 is a cross-sectional view of a painted vehicle part 100 according to one embodiment of the present invention. 1, a mono coating layer 20 is applied to the surface of the base 10 for vehicle parts.

The base member 10 for a vehicle part may be a polyolefin-based material. For example, it may be a polypropylene material, but is not limited thereto.

The mono coating layer 20 may be formed from the above-described coating composition for vehicle parts. In one embodiment, the mono coating layer 20 is applied to the chromium-plated surface of the vehicle component substrate 10 to a thickness of 10 to 20 탆, preferably 12 to 18 탆, more preferably 14 to 16 탆 As shown in FIG. When formed in the above-mentioned range, it is excellent in adhesion with the surface of the vehicle component substrate 10, excellent in color representation and physical properties, and can prevent appearance defects and the like.

The vehicle components include, for example, body colors including bumper, side sill molding, side garnish, side protector and other polyol based materials. But is not limited to, painted parts.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. However, the following examples are provided to aid understanding of the present invention, and the scope of the present invention is not limited to the following examples. The contents not described here are sufficiently technically inferior to those skilled in the art, and a description thereof will be omitted.

Example

The specifications of each component used in the following examples and comparative examples are as follows:

In the acrylic polyol resin, N4-1190 manufactured by Norubi Chemical was used as the non-reactive acrylic polyol resin, and G1-2133 manufactured by Norubi Chemical was used as the reactive acrylic polyol resin.

Lubrizol® 2063 from Lubrizol was used as an adhesion promoter.

As the pigment, S4 serise Colorant manufactured by NORUBIKI CHEMICAL Co., Ltd. was used.

Dibutyltin dilaurate was used as a reaction catalyst.

A light stabilizer (HALS Tinuvin 292, UV Absorber Tinuvin 1130) was used as an additive.

Butyl acetate was used as the solvent.

The resin for the curing agent was HI-100 manufactured by BASF.

Butyl acetate was used as a solvent for the curing agent.

Example 1

As shown in Table 1, 30 parts by weight of non-reactive acrylic polyol resin, 30 parts by weight of reactive acrylic polyol resin, 0.5 parts by weight of adhesion promoter, 0.5 parts by weight of pigment, 1 part by weight of reaction catalyst , 3 parts by weight of an additive and 35 parts by weight of a solvent were mixed to prepare the subject of the coating composition for vehicle parts of the present invention.

Then, 15 parts by weight of a resin for a curing agent and 10 parts by weight of a solvent for a curing agent were mixed to prepare a curing agent. Then, the thus prepared subject and a curing agent were mixed in a ratio of 4: 1 to complete the coating composition for a vehicle component of the present invention.

The coating composition was then rinsed with isopropyl alcohol and coated on the chrome plated surface of the pretreated ABS substrate for vehicle components to form a mono coating layer 14 to 16 microns thick and then cured at 80 DEG C for 30 minutes ) Was applied to complete painting of the vehicle parts base.

Comparative Example 1

A paint composition for a vehicle component was prepared in the same manner as in Example 1 except that the content of the reactive acrylic polyol resin was set to be smaller than the range of the above Example 1.

Comparative Example 2

A paint composition for a vehicle component was prepared in the same manner as in Example 1 except that the content of the non-reactive acrylic polyol resin was set to be larger than the range of the above Example 1.

Comparative Example 3

A paint composition for a vehicle component was prepared in the same manner as in Example 1 except that the content of the reactive acrylic polyol resin was set to be larger than the range of the above Example 1.

Comparative Example 4

A paint composition for a vehicle component was prepared in the same manner as in Example 1 except that the content of the non-reactive acrylic polyol resin was set to be smaller than the range of the above-mentioned Example 1.

Comparative Example 5

A coating composition for a vehicle component was prepared in the same manner as in Example 1 except that the use of an adhesion promoter was excluded, and the content was set outside the range of Example 1.

Comparative Example 6

A paint composition for a vehicle component was prepared in the same manner as in Example 1 except that the content of the adhesion promoter was set to be larger than the range of the above Example 1.

Composition (parts by weight) Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 subject Acrylic polyol
Resin (unreacted) 30 42 36 24 18 30 30 Acrylic polyol
Resin (reactive type) 30 18 24 36 42 30 30 Adhesion promoter 0.5 0.5 0.5 0.5 0.5 - One Pigment 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Reaction catalyst One One One One One One One additive 3 3 3 3 3 3 3 solvent 35 35 35 35 35 35.5 34.5 Total content
(subject) 100 100 100 100 100 100 100 Hardener Resin for hardener 15 20 17 20 18 15 5 Solvent for hardener 10 15 14 10 7 8 15 Total content
(Hardener) 25 35 31 30 25 23 20

Test Example

The physical properties such as adhesion of the specimens of the vehicle parts base material coated in Example 1 and Comparative Examples 1 to 6 were evaluated as follows and shown in Table 2 below.

(1) Appearance: Appearance of discoloration, gloss reduction, sagging property, orange peel and the like were visually evaluated for discernible defects.

(2) Adhesion: A perforated line was cut with a cutter so as to reach the substrate, and 100 squares of size 2 mm x 2 mm were made, adhered to the surface with adhesive cellophane tape, Was evaluated.

(3) Inner sun cream resistance: SPF47 sun cream was applied to a coating film of 0.25g in a size of 5x5 cm, and then allowed to stand at 100 ° C for 1 hour, and then an adhesion test was carried out.

(4) Scratch resistance: According to JISK 6718, scratches occurred over time after scratching a coating film using a sharp tip having a curvature of 0.5R at a load of 500 g according to JISK 6718 (evaluation level: 1 to 5 Level 1: scratch intensive, 5: complete restoration))

(5) Abrasion resistance: A test was performed using a reciprocating abrasion tester at a speed of 500 g at a rate of 60 times / min for 10,000 times.

(6) Heat resistance: The specimens were left in a chamber at a temperature of 90 ± 2 ° C for 110 hours and 300 hours, and then evaluated for appearance (color difference dE < 2.0) and adhesion abnormality.

(7) Moisture resistance: The test piece was left in a chamber having a test temperature of 50 ± 2 ° C. and a relative humidity of 95 ± 2% RH for 240 hours, and then evaluated for appearance (color difference dE <2.0) and initial adhesion test.

(8) Light fastness: 1050 kJ / m ² After checking the quantity of light, color difference dE < 2.0,

Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Exterior ○ × × ○ ○ ○ × Attachment 100/100 100/100 100/100 95/100 80/100 100/100 100/100 My Sun Cream Castle ○ × ○ × × × ○ Scratch resistance ○ × × ○ ○ ○ ○ Abrasion resistance ○ × × ○ ○ ○ ○ Heat resistance ○ × ○ ○ ○ ○ ○ Moisture resistance ○ × × ○ ○ ○ ○ Light resistance  ○    ×  ○  ○  ○    ×  ○

Results of physical property evaluation

Through the above Comparative Examples 1 and 2, when the content of the non-reactive acrylic polyol resin was increased and the content of the reactive acrylic polyol resin was lowered, the curing density was lowered and the resistance to abrasion (abrasion exposure) and heat resistance (Discoloration) and moisture resistance (discoloration) are lowered, and the appearance deteriorates due to deterioration of workability.

It is also seen that, when the content of the non-reactive acrylic polyol resin is lowered and the content of the reactive acrylic polyol resin is increased through Comparative Examples 3 to 4, the adhesion property and the adhesion after the anti-sunscreen property are lowered.

In addition, it was found that the adhesion after the adhesion of the sunscreen was poor in comparison with Example 1 in which the adhesion promoter was added through Comparative Example 5, and when the adhesion promoter was added by 1% or more through Comparative Example 6, the haze Is generated.

On the other hand, as in Example 1, in the case of the present invention, adhesion of the non-reactive acrylic polyol resin to the coating layer was ensured, adhesion which was insufficient in sunscreen property could be supplemented with an adhesion promoter, It can be seen that the use of an acrylic polyol resin can control the curing density to ensure the anti-sunmatic property, scratch resistance, abrasion resistance, heat resistance and moisture resistance.

Therefore, through the above-mentioned experimental results, it can be seen that the vehicle component substrate using the coating composition according to the present invention has excellent effects in virtually all physical properties such as appearance, adhesion, sunscreen property, scratch resistance, abrasion resistance, heat resistance, moisture resistance and light resistance .

10: Base material for vehicle parts 12: Primer coating layer
20: Mono coating layer 22: Base coating layer
30: clear coating layer 100: vehicle parts
200: bumper substrate

Claims (9)

50 to 70 parts by weight of an acrylic polyol resin, 0.1 to 0.5 parts by weight of an adhesion promoter, 0.01 to 1.0 parts by weight of a pigment, 0.1 to 1.5 parts by weight of a reaction catalyst, 0.5 to 8.0 parts by weight of an additive, and 20 to 40 parts by weight of a solvent 100 parts by weight of a subject containing; And
10 to 30 parts by weight of a curing agent comprising a resin for a curing agent and a solvent for a curing agent;
Lt; / RTI &gt;
The acrylic polyol resin is a mixture of a non-reactive acrylic polyol resin and a reactive acrylic polyol resin in a weight ratio of 1: 1.5 to 1.5: 1,
The curing resin is used in an amount of 5 to 20 parts by weight based on 100 parts by weight of the resin,
Wherein the curing solvent is contained in an amount of 5 to 15 parts by weight based on 100 parts by weight of the resin composition.
The method according to claim 1,
In the acrylic polyol resin,
A non-reactive acrylic polyol resin having a glass transition temperature (Tg) of 50 to 60 占 폚, a solid content of 40 to 60% and a weight average molecular weight of 25,000 to 40,000 g / mol; And
A reaction type acrylic polyol resin having a solid content of 60 to 80%, a hydroxyl value of 3 to 5% and a weight average molecular weight of 9,000 to 18,000 g / mol;
Wherein the coating composition for vehicle parts is a coating composition for vehicle parts.
The method according to claim 1,
Wherein the adhesion promoter comprises a phosphoric acid adhesion promoter.
Preparing a chromium-plated vehicle component substrate;
Coating a chromium-plated surface of the substrate with the coating composition for a vehicle component according to any one of claims 1 to 3 to form a mono coating layer; And
Curing the mono coating layer;
Of the vehicle.
5. The method of claim 4,
Pretreating the chromium-plated surface with isopropyl alcohol before painting the coating composition;
Further comprising the steps of:
5. The method of claim 4,
Wherein said curing is carried out at 70 to 90 占 폚 for 20 to 50 minutes.
Chrome plated vehicle parts; And
And a mono-coating layer formed on a chromium-plated surface of the vehicle component,
The mono coating layer is formed from the coating composition for a vehicle part according to any one of claims 1 to 3.
8. The method of claim 7,
Wherein the mono coating layer has a thickness of 10 mu m to 20 mu m.
8. The method of claim 7,
Wherein the vehicle part is a bumper, a side seal molding, a side garnish, or a side protector.

Images