KR102064896B1 - Painting method for vehicle parts and vehicle parts using the same - Google Patents

Abstract

The present invention 1) by mixing a white primer and a curing agent, to prepare a white primer mixture, and diluted with a thinner to the white primer mixture, the coating viscosity is measured in 12 to 16 seconds when measuring the pod cup 4 at 25 ℃ Adjusting to prepare a coating composition for the white primer;
2) A black base mixture was prepared by mixing the black base and the curing agent, and diluted with a thinner to the black base mixture, and the coating viscosity was adjusted to 12 to 16 seconds when measured with a pod cup 4 at 25 ° C. Preparing a coating composition for the base;
3) forming a white primer layer by coating the coating composition for white primer of step 1) on the vehicle interior parts;
4) coating the coating composition for the black base of step 2) on the vehicle interior part in which the white primer layer of step 3) is formed, thereby forming a black base layer on the upper surface of the white primer layer; And
5) The present invention relates to a coating method of a vehicle interior part comprising the step of coating an ultraviolet curable cree on the upper surface of the black base layer of step 4) to form an ultraviolet cree coating layer.
It is possible to form a coating layer having excellent adhesion with a vehicle interior component made of plastic, and the vehicle interior component in which the ultraviolet curable coating layer is formed by the coating method of the present invention has excellent appearance, and is excellent in impact resistance, scratch resistance, light resistance, It can provide excellent physical properties such as light leakage, moisture resistance, sunscreen resistance, and, in addition, to provide a coating method for vehicle interior parts and vehicle interior parts that can form letters by laser cutting when letter marking is required. Can be.

Description

PAINTING METHOD FOR VEHICLE PARTS AND VEHICLE PARTS USING THE SAME}

The present invention relates to a coating method for a vehicle interior part and a vehicle interior part. More particularly, the present invention relates to a coating method for forming a coating layer having a multilayer structure on a vehicle interior part and a vehicle interior component having a coating layer having a multilayer structure. It is about.

Recently, vehicle parts have been reduced in weight for the purpose of increasing fuel efficiency. The most common method is replacing metal to plastic.

When plastics are applied to vehicle parts, plastics have a number of advantages, such as being light and colored, without corrosion, compared to metals, but paintability and other functionality need to be imparted for application to vehicle parts.

In addition, plastics are vulnerable to deformation due to chemicals, erosion, ultraviolet rays, heat, and the like. In addition, plastics have surface area defects due to marks, surface defects and color limitations during injection. In order to solve these problems, conventionally, oily acrylic lacquer is coated to compensate for defects of plastic materials.

However, the conventional oil-based acrylic lacquer paint has good physical properties such as heat resistance, moisture resistance, and adhesiveness, but has a poor scratch resistance, and thus does not give a luxurious feeling because the texture is cold and soft when contacted with the coating film and human skin. there was.

As the Republic of Korea Patent No. 10-0643335, by coating the resin composition on the surface of the vehicle parts to form a coating film to prevent component damage due to mechanical, physical and chemical effects from the outside, to maintain long-term durability and reliability Was intended.

However, such a paint composition will be said to be unsuitable for application to vehicle parts composed of plastic in the trend of replacing metal with plastic for light weight. In other words, the plastics used in the interior of the vehicle are largely divided into instrument panels, door trims, center facia panels, center consoles, audio panels, and grip handles. A variety of applications, such as), may mean that they can be exposed to various environments. Plastic parts exposed to such various environments are vulnerable to chemicals, erosion, ultraviolet rays, heat deformation, etc., and may have surface defects resulting from marks, surface defects, and color limitations in injection. In addition, scratches are easily generated by external forces, and quality problems frequently occur because of the inability to restore them.

Accordingly, there is a demand for a coating method capable of realizing excellent properties such as adhesion and scratch resistance when applied to a vehicle interior plastic part.

In solving the above-described problems, an object of the present invention is to paint a vehicle interior parts to form a white primer layer exhibiting excellent adhesion with a polycarbonate mainly used as a vehicle interior plastic and a vehicle interior parts formed with a white primer layer In providing.

In addition, it is an object of the present invention to provide a coating method for a vehicle interior part which exhibits the color of the entire part and forms a black base layer having good laser cutting property, and a vehicle interior part having a black base layer formed thereon.

In addition, it is an object of the present invention to provide a coating method for a vehicle interior parts to form an ultraviolet curable cree layer showing excellent coating properties, such as scratch resistance, light resistance, and a vehicle interior parts formed with an ultraviolet curable cree layer.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" may include the plural forms as well, unless the context clearly indicates otherwise. Also, as used herein, "comprise" and / or "comprising" specifies the presence of the mentioned shapes, numbers, steps, actions, members, elements and / or groups of these. It is not intended to exclude the presence or the addition of one or more other shapes, numbers, acts, members, elements and / or groups.

In one embodiment of the present invention, the present invention 1) by mixing a white primer and a curing agent, to prepare a white primer mixture, by mixing the thinner in the white primer mixture, the coating viscosity is measured by Pod Cup No. 4 at 25 ℃ Time, adjusting to 12 to 16 seconds to prepare a coating composition for the white primer; 2) Mixing the black base and the curing agent to prepare a black base mixture, and mix the thinner to the black base mixture, the coating viscosity is adjusted to 12 to 16 seconds when measured by the Pod Cup No. 4 at 25 ℃ for black base Preparing a coating composition; 3) forming a white primer layer by coating the coating composition for white primer of step 1) on the vehicle interior parts; 4) coating the coating composition for the black base of step 2) on the vehicle interior part in which the white primer layer of step 3) is formed, thereby forming a black base layer on the upper surface of the white primer layer; And 5) coating an ultraviolet curable cree on the upper surface of the black base layer of step 4) to form an ultraviolet cree coating layer.

In one embodiment of the present invention, the white primer mixture of step 1) of the present invention may include a white primer and a curing agent in a weight ratio of 8: 1 to 12: 1.

In one embodiment of the present invention, the black base mixture of step 2) of the present invention may include a black base and a curing agent in a weight ratio of 8: 1 to 12: 1.

In one embodiment of the present invention, step 3) of the present invention may form a white primer layer having a thickness of 15 to 20㎛.

In one embodiment of the present invention, step 4) of the present invention may form a black base layer having a thickness of 20 to 25㎛.

In one embodiment of the present invention, the white primer of the present invention is caprolactone modified acrylic resin; Acrylic resin having a glass transition temperature of 60 to 80 ° C; Acrylic resin which is excellent in adhesiveness with polycarbonate (PC); White pigments; It may include a pigment dispersant and an organic solvent.

In one embodiment of the present invention, the caprolactone modified acrylic resin of the present invention is an acrylic resin polymerized in methyl isobutyl ketone (MIBK) and propylene glycol monomethyl ether acetate, non-volatile content (Non-Volatile) 65 to 70%, Acid values 5-6, hydroxyl values (OHV) 55-60, and glass transition temperatures -5-10C.

In one embodiment of the invention, the acrylic resin having a glass transition temperature of 60 to 80 ℃ of the present invention is an acrylic resin polymerized in butyl acetate (BuAc), non-volatile content (Non-Volatile) 45 to 55%, acid value 2.5 to 3.5 and hydroxyl values (OHV) 19-20.

In one embodiment of the present invention, the acrylic resin excellent in adhesion with the polycarbonate of the present invention is an acrylic resin polymerized in butyl acetate (BuAc) and methyl ethyl ketone (MEK), 40 to non-volatile (Non-Volatile) 60%, acid value 2-3, hydroxyl value (OHV) 14-15, and glass transition temperature 80-90 degreeC.

In one embodiment of the present invention, the black base of the present invention is a high hardness acrylic resin; Caprolactone modified acrylic resins; Acrylic resin having a weight average molecular weight (Mw) of 20,000 to 40,000; Black pigment; Pigment dispersants; Reaction catalyst; It may include a leveling agent and an organic solvent.

In one embodiment of the present invention, the high hardness acrylic resin of the present invention is an acrylic resin polymerized in butyl acetate (BuAc), non-volatile content (Non-Volatile) 50 to 60%, acid value 4.5 to 5.5, hydroxyl value (OHV ) 40 to 50 and a glass transition temperature of 60 to 65 ℃.

In one embodiment of the present invention, the caprolactone modified acrylic resin of the present invention is an acrylic resin polymerized in methyl isobutyl ketone (MIBK) and propylene glycol monomethyl ether acetate, non-volatile content (Non-Volatile) 65 to 70%, Acid values 5-6, hydroxyl values (OHV) 55-60, and glass transition temperatures -5-10C.

In one embodiment of the present invention, the acrylic resin having a weight average molecular weight (Mw) of 20,000 to 40,000 of the present invention is an acrylic resin polymerized in butyl acetate (BuAc) and methyl ethyl ketone (MEK), and non-volatile components (Non-Volatile). ) 40 to 60%, acid number 2 to 3, hydroxyl value (OHV) 14 to 15 and glass transition temperature of 80 to 90 ℃.

In one embodiment of the present invention, the ultraviolet curable cree of the present invention is a polyfunctional urethane acrylate oligomer; Polyfunctional acrylate monomers; Photoinitiators; Ultraviolet stabilizers; It may include a leveling agent and an organic solvent.

In one embodiment of the present invention, the multifunctional urethane acrylate oligomer of the present invention may include a 5 to 6 functional urethane acrylate oligomer and a bifunctional urethane acrylate oligomer.

In one embodiment of the present invention, the multifunctional acrylate monomer of the present invention may include an acrylate monomer including 3 to 6 unsaturated groups and an acrylate monomer including two unsaturated groups.

In one embodiment of the invention, the invention is a substrate; And an ultraviolet curable coating layer formed on the base material, wherein the ultraviolet curable coating layer relates to a vehicle interior component formed by the coating method of the vehicle interior component.

In one embodiment of the present invention, the ultraviolet curable coating layer of the present invention is a white primer layer formed in contact with the substrate layer; A black base layer formed on an upper surface of the white primer layer; And an ultraviolet curable cree layer formed on an upper surface of the black base layer.

As described above, the vehicle interior component made of plastic and the coating layer excellent in adhesion can be formed, and the vehicle interior component in which the UV curable coating layer is formed by the coating method of the present invention exhibits excellent appearance, impact resistance and It can exhibit excellent physical properties such as scratch resistance, light resistance, light leakage, moisture resistance, sun cream resistance, and the like, and, in addition, when a letter is required, the method of painting the interior parts of a vehicle, which can be formed by laser cutting, and the vehicle Internal components can be provided.

1 is a flowchart illustrating a painting method of a vehicle interior part according to an embodiment of the present invention.

1 is a flow chart for a method for painting interior parts of a vehicle according to an embodiment of the present invention, specifically 1) preparing a coating composition for a white primer (S100); 2) preparing a coating composition for a black base (S200); 3) forming a white primer layer on the vehicle interior part (S300); 4) forming a black base layer on the upper surface of the white primer layer (S400); And 5) forming an ultraviolet CREE coating layer on the upper surface of the black base layer (S500).

Step 1) (S100) is to prepare a coating composition for the white primer, caprolactone-modified acrylic resin; Acrylic resin having a glass transition temperature of 60 to 80 ° C; Acrylic resin which is excellent in adhesiveness with polycarbonate (PC); White pigments; A white primer containing a pigment dispersant and an organic solvent and a curing agent are mixed in a weight ratio of 12: 1, preferably in a weight ratio of 10: 1 to prepare a white primer mixture, and the white primer mixture is diluted with thinner. When measured by the Pod Cup No. 4 at 25 ° C, it is adjusted to 12 to 16 seconds, preferably the coating viscosity is adjusted to 14 seconds to prepare a coating composition for white primer.

The white primer is 17 to 27 wt% caprolactone modified acrylic resin; 15 to 25% by weight of an acrylic resin having a glass transition temperature of 60 to 80 ° C; 7 to 15 wt% of acrylic resin having excellent adhesion to polycarbonate (PC); 20-25 wt% of a white pigment; 0.5 to 1.0 wt% of the pigment dispersant and 15 to 25 wt% of the organic solvent.

The caprolactone-modified acrylic resin is an acrylic resin polymerized from methyl isobutyl ketone (MIBK) and propylene glycol monomethyl ether acetate, non-volatile content (Non-Volatile) 65 to 70%, acid value 5 to 6, hydroxyl value (OHV ) 55 to 60 and a glass transition temperature of -5 to -10 ° C, preferably 66% non-volatile content, an acid value of 5.5, a hydroxyl value (OHV) 56 and a glass transition temperature of -7 ° C.

When the caprolactone-modified acrylic resin is included in less than 17% by weight, there is a problem that the adhesion to the plastic substrate is poor, if the content exceeds 27% by weight, the drying is late, the drying is late It is difficult to separate from the black base layer, resulting in poor laser cutting property.

The acrylic resin having a glass transition temperature of 60 to 80 ° C. is an acrylic resin polymerized in butyl acetate (BuAc), and has a nonvolatile content of 45 to 55%, an acid value of 2.5 to 3.5, and a hydroxyl value (OHV) of 19 to 50. 20, preferably 50% non-volatile content, acid value 3.0, and hydroxyl value (OHV) 19.7.

When the acrylic resin having a glass transition temperature of 60 to 80 ° C. is included in less than 15% by weight, a problem occurs that the coating film hardness is lowered. When the glass transition temperature is more than 25% by weight, the adhesion to the plastic substrate is deteriorated. Occurs.

The acrylic resin excellent in adhesion to the polycarbonate (PC) is an acrylic resin polymerized in butyl acetate (BuAc) and methyl ethyl ketone (MEK), 40 to 60% of non-volatile content, acid value of 2-3, The hydroxyl value (OHV) is 14 to 15 and the glass transition temperature is 80 to 90 ° C., and preferably the non-volatile content is 50%, the acid value 2.6, the hydroxyl value (OHV) 14.5 and the glass transition temperature 87 ° C.

When the acrylic resin having excellent adhesion with the polycarbonate is included in less than 7% by weight, the adhesion with the plastic substrate is lowered, and as the drying is slowed, miscibility with the black base layer may occur. When the weight percentage is exceeded, problems such as orange peel may occur due to poor paintability. Orange peel in the present invention means that a large number of irregularities such as orange peel occurs when the leveling of the coating appearance is bad.

The white pigment is titanium dioxide, for example, DuPont R-902 may be used.

When the white pigment is included in less than 20% by weight, the concealability is lowered, the light leakage is worse, when it exceeds 25% by weight, due to the excessive amount of pigment, there is a problem that the adhesion to the plastic substrate is inferior.

The pigment dispersant may be used to select a dispersant capable of preventing re-agglomeration for dispersion stability, and for example, may use BYPER's DISPERBYK-2050.

When the pigment dispersant is included in less than 0.5% by weight, the pigment particles may not be sufficiently dispersed, may cause problems of reaggregation. When the pigment dispersant is included in an amount of more than 1.0% by weight, the low molecular weight material may be excessively used, resulting in deterioration of physical properties. May occur.

The organic solvent uses an organic solvent that does not contain Benzene-Toluene-Xylene (BTX), and does not cause erosion on the plastic substrate or a volatilization rate of 100 or more so that the solvent does not affect the substrate by being rapidly volatilized during spray coating. All can be used without limitation. For example, acetate-based, ester-based, hydrocarbon-based, etc. can be used, and any organic solvent that can be easily used by those skilled in the art can be used in addition to the organic solvents of the above examples.

When the organic solvent is included in less than 15% by weight, the viscosity is high, difficult to disperse the pigment, and when it contains more than 25% by weight, the viscosity of the paint is lowered, the pigment is easy to settle, so paint storage properties The problem of becoming poor arises.

Step 2) (S200) is a step of preparing a coating composition for the black base (S200), high hardness acrylic resin; Caprolactone modified acrylic resins; Acrylic resin having a weight average molecular weight (Mw) of 20,000 to 40,000; Black pigment; Pigment dispersants; Reaction catalyst; A black base including a leveling agent and an organic solvent and a curing agent are mixed in a weight ratio of 12: 1, preferably in a weight ratio of 10: 1 to prepare a black base mixture, and using a thinner to the black base mixture. When diluted, the coating viscosity is measured at 12 to 16 seconds when measured by the Pod Cup No. 4 at 25 ° C, and preferably, the coating viscosity is adjusted to 14 seconds to prepare a coating composition for a black base.

The black base is 40 to 50% by weight of a high hardness acrylic resin; 3-7% by weight of caprolactone-modified acrylic resin; 3 to 7 wt% of an acrylic resin having a weight average molecular weight (Mw) of 20,000 to 40,000; 3 to 5 weight percent black pigment; 0.5 to 1.0 wt% pigment dispersant; 0.01 to 0.03% by weight of reaction catalyst; It may include 0.1 to 0.3% by weight leveling agent and 15 to 20% by weight of the organic solvent.

The high hardness acrylic resin includes a high hardness acrylic resin to form an excellent appearance when forming a black base layer using a black base, the high hardness acrylic resin is polymerized in butyl acetate (BuAc) One acrylic resin, non-volatile content (Non-Volatile) 50 to 60%, acid value 4.5 to 5.5, hydroxyl value (OHV) 40 to 50 and glass transition temperature 60 to 65 ℃, preferably non-volatile (Non-Volatile) ) 55%, acid value 5, hydroxyl value (OHV) 45 and glass transition temperature 63 ° C.

When the high hardness acrylic resin is included less than 40% by weight, a problem may occur that the adhesion with the white primer layer is worse, when it exceeds 50% by weight, there is a problem of low economic efficiency.

The caprolactone-modified acrylic resin is an acrylic resin polymerized from methyl isobutyl ketone (MIBK) and propylene glycol monomethyl ether acetate, non-volatile content (Non-Volatile) 65 to 70%, acid value 5 to 6, hydroxyl value (OHV ) 55 to 60 and a glass transition temperature of -5 to -10 ° C, preferably 66% non-volatile content, an acid value of 5.5, a hydroxyl value (OHV) 56 and a glass transition temperature of -7 ° C.

When the caprolactone-modified acrylic resin is included in an amount less than 3% by weight, the adhesion with the white primer layer is deteriorated. When the caprolactone-modified acrylic resin is contained in an amount of more than 7% by weight, the coating film hardness decreases, resulting in a problem of deterioration of the laser cutting property. .

The acrylic resin having a weight average molecular weight (Mw) of 20,000 to 40,000 and preferably 28,000 is an acrylic resin polymerized in butyl acetate (BuAc) and methyl ethyl ketone (MEK), and 40 to 60% of a non-volatile component (Non-Volatile). , Acid value 2 to 3, hydroxyl value (OHV) 14 to 15 and glass transition temperature of 80 to 90 ℃, preferably 50% non-volatile (Non-Volatile), acid value 2.6, hydroxyl value (OHV) 14.5 and glass Transition temperature is 87 ° C.

When the weight average molecular weight (Mw) is less than 3% by weight of the acrylic resin of 20,000 to 40,000, the coating film hardness is lowered, the problem that the laser cutting property worsens, when exceeding 7% by weight, workability The problem arises that the leveling is deteriorated due to degradation.

The black pigment may be carbon black, for example, FW-200 of Degussa, but the black pigment may be used as the carbon black at the level of those skilled in the art without being limited to the above examples.

When the black pigment is included in less than 3% by weight, there is a problem in that the concealability is lowered and the light leakage worsens. When the black pigment is included in an amount of more than 5% by weight, the pigment content is excessive, resulting in poor adhesion. .

The pigment dispersant may be used to select a dispersant capable of preventing re-agglomeration for dispersion stability, and for example, may use BYPER's DISPERBYK-2050.

When the pigment dispersant is included in less than 0.5% by weight, the pigment particles may not be sufficiently dispersed, may cause problems of reaggregation. When the pigment dispersant is included in an amount of more than 1.0% by weight, the low molecular weight material may be excessively used, resulting in deterioration of physical properties. May occur.

The reaction accelerator is a urethane reaction accelerator, is included to improve the reaction rate of the hydroxyl group and the curing agent of the acrylic resin, when included less than 0.01% by weight, the effect of improving the reaction rate of the hydroxyl group and the curing agent of the acrylic resin is insufficient, When it contains more than 0.03% by weight, the pot life is shortened to cause workability problems.

The leveling agent may improve surface leveling, and may prevent orange peel, filling and the like. The leveling agent can be used all that can be easily selected by those skilled in the art, such as acrylic, silicone, and the like, but is not limited to the above examples.

When the leveling agent is included in less than 0.1% by weight, there is a problem that the surface leveling enhancement effect is inadequate, when contained in more than 0.3% by weight, the surface energy is small, poor appearance, such as poor wetting during cree coating Can be.

The organic solvent can be used without limiting the organic solvent that does not contain BTX (Benzene-Toluene-Xylene). For example, acetate-based, ester-based, hydrocarbon-based, etc. can be used, and any organic solvent that can be easily used by those skilled in the art can be used in addition to the organic solvents of the above examples.

When the organic solvent is included in less than 15% by weight, a problem of difficulty in mixing raw materials due to high viscosity occurs. When the organic solvent is included in an amount of more than 20% by weight, the viscosity of the paint is lowered, so that the pigment is easily precipitated. There is a problem of poor storage.

Thereafter, step 3) is a step of forming a white primer layer on the vehicle interior component. Step 3) (S300) is to coat the coating composition for the white primer of step 1) on the plastic material parts, prior to coating the coating composition for the white primer, pretreatment of the plastic substrate with alcohol of C ₁ to C ₁₀ do. Preferably isopropanol can be used to proceed the pretreatment process. The pretreatment process is to remove impurities present on the surface of the plastic substrate in order to coat the coating composition for the white primer and to improve adhesion between the white primer layer formed and the plastic substrate. After the pretreatment process, the coating composition for the white primer is coated to form a white primer layer having a thickness of 15 to 20 μm.

When the white primer layer is formed in step 3) (S300), the black base layer is formed in step 4) (S400). More specifically, 3) the step (S300) on the plastic substrate, to form a white primer layer, and to coat the coating composition for the black base on the upper surface of the white primer layer, a black base layer of 20 to 25㎛ thickness To form. At this time, after the 3) step (S300) process, 4) before proceeding to the step (S400), the white primer layer is left to dry for 5 to 10 minutes at room temperature (25 ℃). Preferably left for 8 minutes at room temperature, so that the surface of the white primer layer is completely dried. A black base layer having a thickness of 20 to 25 μm is formed and dried at 80 ° C. for 30 minutes.

Step 5), the step (S500) is to form an ultraviolet cree coating layer on the upper surface of the black base layer, more specifically, the ultraviolet curable cree is coated on the upper surface of the black base layer, and dried at 60 ℃ for 5 minutes , 110mW / cm ² , and 1500mJ / cm ² irradiated with ultraviolet light to form an ultraviolet curable type cree layer.

The ultraviolet curing type cree is a polyfunctional urethane acrylate oligomer; Polyfunctional acrylate monomers; Photoinitiators; Ultraviolet stabilizers; A acrylate monomer comprising a leveling agent and an organic solvent, more specifically, 25 to 30% by weight of 5 to 6 functional urethane acrylate oligomer, 5 to 10% by weight of bifunctional urethane acrylate oligomer, and 3 to 6 unsaturated groups 3 to 7% by weight, 3 to 7% by weight of acrylate monomer containing two unsaturated groups, 2 to 4% by weight of photoinitiator; 1-3% by weight of UV stabilizer; 0.1 to 0.5% by weight of leveling agent and 45 to 55% by weight of organic solvent.

The multifunctional urethane acrylate oligomer may include a 5 to 6 functional urethane acrylate oligomer and a bifunctional urethane acrylate oligomer. The 5- to 6-functional urethane acrylate oligomer is a urethane acrylate having 5 to 6 unsaturated groups to impart hardness to the coating film can exhibit excellent scratch resistance. The unsaturated group is a vinyl group. When the content of 5 to 6 functional urethane acrylate oligomer is less than 25% by weight, the problem of scratch resistance is lowered. When the content is more than 30% by weight, the flexibility of the coating film is lowered and the adhesion is lowered. A problem arises.

The 5- to 6-functional urethane acrylate oligomer, for example, ENTIS's EB1290, UP118, EB5129, Mitsui's RA6800, US yarn's PU610, ETERNAL's Etercure 6145-100 and the like can be used, but is not limited to the above examples.

The bifunctional urethane acrylate oligomer is a urethane acrylate having two vinyl groups, which are unsaturated groups, to impart flexibility to the coating film, to prevent cracks in thick films, and to enable polishing when foreign substances are generated. When the bifunctional urethane acrylate oligomer is included in less than 5% by weight, the coating film flexibility is lowered, the impact resistance is lowered, or cracks occur due to the difference in curing shrinkage with the base layer, when it exceeds 10% by weight And the hardness of a coating film falls and the problem of inferior scratch resistance arises.

The bifunctional urethane acrylate oligomer can be used, such as PU2100, PU2200, Sartomer's CN8003, etc. of the yarn, but is not limited to the above examples.

The acrylate monomer including 3 to 6 vinyl groups as the unsaturated group is preferably an acrylate monomer including 3 or 4 unsaturated groups, and serves to improve surface hardness and curing density.

When the acrylate monomer containing 3 to 6 unsaturated groups is included in an amount of less than 3% by weight, a problem occurs that the scratch resistance is lowered due to a decrease in the curing density, and when the amount exceeds 7% by weight, the curing density is excessive. There arises a problem that the adhesion decreases.

Examples of the acrylate monomer containing 3 to 6 unsaturated groups include trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol. It includes any one or more selected from the group consisting of hexaacrylate, and is not limited to the above examples.

The acrylate monomer including two vinyl groups which are the unsaturated groups serves to prevent the curing shrinkage of the coating film to improve adhesion.

Including less than 3% by weight of the acrylate monomer containing two unsaturated groups, a problem that the adhesion is weakened, when containing more than 7% by weight, a problem that the scratch resistance is lowered.

The acrylate monomer including two unsaturated groups includes any one or more selected from the group consisting of hexanediol diacrylate, tripropylene glycol diacrylate, and dimethylol tricyclodecane diacrylate, and is not limited to the above examples. .

The photoinitiator is a substance which forms a radical to cause polymerization of the polyfunctional urethane acrylate oligomer and the polyfunctional acrylate monomer, and includes a short wavelength initiator that absorbs ultraviolet rays of 220 to 280 nm and a long wavelength initiator that absorbs ultraviolet rays of 280 to 420 nm, respectively. It is preferable to mix and use 1 or more types. The short wavelength initiator and the long wavelength initiator may be used in a ratio of 3: 1, but are not limited to the examples. When the photoinitiator is included in less than 2% by weight, the curing efficiency is lowered, the adhesion and the scratch resistance is lowered, it is included in excess of 4% by weight, causing a cost increase.

2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-1- {4- [4- (2 as the short wavelength initiator -Hydroxy-2-methyl-propionyl) -benzyl] -phenyl} -2-methyl-propane-l-one and methylbenzoylformate may be used, but is not limited to examples. . 2,4,6-trimethylbenzoyldiphenylphosphine oxide or bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide may be used as the long wavelength initiator, but is not limited thereto.

The UV stabilizer is preferably used in combination with a UV absorber for preventing adhesion degradation and yellowing after the weathering test and a hindered amine light stabilizer for preventing gloss reduction, cracking, choking, etc. after the weathering test. The ultraviolet absorber and the hindered amine light stabilizer are preferably used in a ratio of 2: 1, but are not limited to the above examples. When the mixture of the ultraviolet absorber and the hindered amine light stabilizer is included in less than 1% by weight, resistance to ultraviolet rays, etc., is poor, resulting in deterioration in appearance quality such as yellowing, cracking, and peeling, and more than 3% by weight. In this case, the formation of radicals of the photoinitiator is hindered, resulting in the deterioration of physical properties due to the lowering of curing efficiency.

The UV absorber may be used in the benzotriazole-based or triazine-based, more specifically 2- (2H-benzotriazol-2-yl) -4,6- dietpentylphenol, 2- (2H-benzo Triazol-2-yl) -6- (1-methyl-1-phenylethyl) -4- (1,1,3,3-tetramethylbutyl) phenol, 2- [4-[(2-hydroxy- 3-dodecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine and 2- [4-[(2-hydroxy Oxy-3-tridecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) 1,3,5-triazine used at least one selected from the group consisting of Possible but not limited to examples.

 The hindered amine light stabilizer is bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate or 2,4-bis [N-butyl-N- (1-cyclohexilox) C-2,2,6,6-tetramethylpiperidin-4-yl) amino] -6- (2-hydroxyethylamine) -1,3,5-triazine can be used, but in the above example It is not limited.

The leveling agent may be used both silicone-based or acrylic-based leveling agent, but is not limited to the example, for example, BYK355, BYK358, BYK306, BYK310, BYK333, etc., but is not limited to the example.

When the leveling agent is included in less than 0.1% by weight, the effect of the leveling agent may be insignificant, resulting in appearance defects such as orange peel, and when included in an amount exceeding 0.5% by weight, excessive foaming occurs in the paint to improve workability. Is lowered.

The organic solvent may be used in general, all widely used solvents, for example, alcohol, hydrocarbon, ketone, ester, ether can be used for all, but for use in vehicle interior parts, BTX is included It is preferable not to use a hydrocarbon organic solvent.

The organic solvent is to improve the workability by adjusting the viscosity of the paint, when included in less than 45% by weight, when the viscosity of the paint is increased, the paint workability worsens, when containing more than 55% by weight, As the viscosity is lowered, a chilling flow occurs during painting.

Production Example  One

White For primer  Coating composition, coating composition for black base and ultraviolet curing type Cree  Produce

The composition as shown in Tables 1 to 3 below was prepared by mixing the coating composition for the white primer, the coating composition for the black base, and the ultraviolet curing type cree.

Composition of Coating Composition for White Primer Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Suzy N3-0252 25 30 20 25 N3-0520 20 15 27 15 AKLATE AA-5504 9 9 7 10 Pigment R-902 23 23 23 27 Dispersant DISPERBYK-2050 0.5 0.5 0.5 0.5 Organic solvent Butyl acetate 12.5 12.5 12.5 12.5 Isobutyl Acetate 10 10 10 10 Sum 100 100 100 100

N3-0252: caprolactone modified acrylic resin

N3-0520: Acrylic resin with glass transition temperature of 60 to 80 ° C

AKLATE AA-5504: Acrylic resin with excellent PC material adhesion

Composition of paint composition for black base Example 2 Comparative Example 4 Comparative Example 5 Comparative Example 6 Suzy N3-2090 48 43 38 45 N3-0252 5 10 7 5 AKLATE AA-5504 6 6 14 6 Pigment FW-200 5 5 5 2 Dispersant DISPERBYK-2050 0.5 0.5 0.5 0.5 Curing catalyst Dibutyl tin dilaurate 0.01 0.01 0.01 0.01 Leveling agent BYK-333 0.2 0.2 0.2 0.2 Organic solvent Butyl acetate 15.29 15.29 15.29 15.29 Isobutyl Acetate 20 20 20 20 Sum 100 100 100 100

N3-2090: high hardness acrylic resin

N3-0252: caprolactone modified acrylic resin

AKLATE AA-5504: Acrylic resin with weight average molecular weight (Mw) of 20,000 to 40,000

Composition of UV Curable Cree Example 3 Comparative Example 7 Comparative Example 8 Comparative Example 9 5-6 functional urethane acrylate oligomer A 27 30 22 27.9 Bifunctional urethane acrylate oligomer B 6 3 8 6 Acrylate monomer containing 3 to 6 unsaturated groups C 5 5 7 5 Acrylate monomer containing two unsaturated groups D 6 6 7 6 Photoinitiator E-1 3 3 3 3 E-2 One One One One UV stabilizer F-1 1.2 1.2 1.2 0.6 F-2 0.6 0.6 0.6 0.3 Leveling agent G 0.2 0.2 0.2 0.2 Organic solvent H-1 25 25 25 25 H-2 25 25 25 25 Sum 100 100 100 100

A: RA-6800 from Mitsui Corporation

B: PU-2100 of US yarn

C: pentaerythritol triacrylate

D: hexanediol diacrylate

E-1: Irgacure1173 from BASF

E-2: Irgacure819 from BASF

F-1: Tinuvin 479 from BASF

F-2: Tinuvin 292 from BASF

G: BYK's BYK-333

H-1: ethyl acetate

H-2: normal butanol

Preparation Example 2

Manufacture of vehicle interior parts

The curing agent added for curing the white primer and the black base paint was a hexamethylene diisocyanate trimer system having excellent yellowing resistance and weather resistance, which was diluted with 55% solids in propylene glycol monomethyl ether acetate.

The white primer and the curing agent were mixed at 10: 1, diluted with a thinner, and adjusted to a coating viscosity of 14 seconds (4 times at Pod Cup, 25 ° C). The black base and the curing agent were mixed at 10: 1, diluted with a thinner, and adjusted to a coating viscosity of 14 seconds (4 times at Pod Cup, 25 ° C). The polycarbonate material was pretreated with isopropanol and then coated with a coating composition for white primer at 15 to 20 μm. After standing at 25 ° C. for about 8 minutes, the black base was coated with 20 to 25 μm and dried at 80 ° C. for 30 minutes. After laser cutting, UV curable crees were coated and dried at 60 ° C. for 5 minutes, and then irradiated with UV under conditions of 110 mW / cm 2 and 1500 mJ / cm 2 to manufacture a vehicle interior part having a multilayer structure.

Example

Appearance and physical property evaluations were performed with different coating layers of the vehicle interior parts. The composition of the coating layer is shown in Table 4 below.

Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 primer Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Example 1 Example 1 Example 1 Example 1 Example 1 Base Example 2 Example 2 Example 2 Example 2 Comparative Example 4 Comparative Example 5 Comparative Example 6 Example 2 Example 2 Example 2 Cree Example 3 Example 3 Example 3 Example 3 Example 3 Example 3 Example 3 Comparative Example 7 Comparative Example 8 Comparative Example 9

The physical property evaluation method is as follows more specifically.

(1) Adhesion: After cutting 11 lines horizontally and vertically at intervals of 2 mm using a cutter knife to make 100 pieces of monarch, the tape was taped to observe peeling.

(2) Sun Cream Resistance: Lay two sheets of white cotton cloth of the same size on acrylic plate (50 × 50mm), apply sunscreen 0.25g on the front surface, put it on the painted surface, leave it at 80 ℃ × 1 hour, wash it with neutral detergent The external appearance and adhesiveness of the coating film were evaluated.

(3) Moisture resistance: After leaving for 168 hours at 50 ° C. and 95% RH conditions, the resultant was taken out to remove water and evaluated for appearance and adhesion after one hour.

(4) Scratch resistance: After scratching a length of 100mm with a load of 0.5kgf and a frictional speed of 100mm / sec using a sapphire scratcher once, the surface damage is not recognized or weakly recognized by examining the degree of surface damage. The case was judged to be good.

(5) Impact resistance: It was judged to be satisfactory if peeling of a core having a diameter of 0.5 inch on the coated surface was dropped from a height of 20 cm to a weight of 0.5 kg, and no peeling occurred on the coated film surface.

(6) Light resistance: The coated specimen was irradiated with 126MJ / m2 (black panel temperature 89 ° C, humidity 50% RH, irradiation intensity 65 ~ 100W / m2) with xenon arc light source to evaluate the discoloration and adhesion of the coated film appearance.

The evaluation result is as follows.

Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 Exterior Good Bad Good Good Bad Bad Good Bad Good Good Adhesion Good Bad Bad Bad Good Good Good Bad Good Good Sun Cream Resistance Good - - - Good Good Good - Good Good Moisture resistance Good - - - Good Good Good - Good Good Scratch resistance Good - - - Good Good Good - Bad Good Impact resistance Good - - - Good Good Good - Good Good Light resistance Good - - - Good Good Good - Good Bad Light leak Good Bad Good Good Good Good Bad Good Good Good laser
Cutting property Good Bad Good Good Bad Good Good Good Good Good

In Comparative Example 1, the glass transition temperature was -7 ° C. in the white primer, and an excessive amount of N3-0252 resin, which was difficult to dry at room temperature, was added to the white layer during laser cutting by mixing with the black base. Defects and poor adhesion occurred. In Comparative Example 2, the glass transition temperature was 70 ° C. in the white primer, and an excessive amount of hard N3-0520 resin was added, resulting in poor adhesion to the material. In Comparative Example 3, when the white pigment was added in the white primer, adhesion with the material was poor. In Comparative Example 4, the glass transition temperature was -7 ° C in the black base, and an excessive amount of soft N3-0252 was added. The laser cutting property was deteriorated, resulting in damage to the material. In Comparative Example 5, a small amount of N3-2090 and an excessive amount of AKLATE AA-5504 were added to the black base, resulting in poor workability and poor coating film leveling. Comparative Example 6 is a case where a small amount of black pigment is added in the black base, the hiding is not good, poor light leakage. In Comparative Example 7, cracks due to hardening shrinkage occurred when a small amount of bifunctional urethane acrylate was added in the ultraviolet curable creeper, and the adhesion with the base layer was also poor. In Comparative Example 8, when a small amount of 5 to 6 functional urethane acrylate was added in the ultraviolet curing type cree, the coating film hardness was lowered and the scratch resistance was poor. In Comparative Example 9, the content of the UV stabilizer in the UV-curable cree was less than 1, and the adhesion was poor after the light resistance.

On the contrary, in Example 1, the appearance, adhesiveness, sunscreen resistance, moisture resistance, scratch resistance, impact resistance, light resistance, light leakage, and laser cutting resistance were all good.

Claims (18)

1) 17 to 27% by weight of caprolactone modified acrylic resin; 15 to 25% by weight of an acrylic resin having a glass transition temperature of 60 to 80 ° C; 7 to 15% by weight of an acrylic resin polymerized in butyl acetate (BuAc) and methyl ethyl ketone (MEK) to have excellent adhesion to polycarbonate (PC); 20-25 wt% of a white pigment; A white primer mixture was prepared by mixing a white primer and a curing agent containing 0.5 to 1.0% by weight of a pigment dispersant and 15 to 25% by weight of an organic solvent. The white primer mixture was diluted with thinner, and the coating viscosity was 25 ° C. Measuring the number of pod cups at 4 to 12 to 16 seconds to prepare a coating composition for white primer;
2) 40-50% by weight of high hardness acrylic resin; 3-7% by weight of caprolactone-modified acrylic resin; 3 to 7 wt% of an acrylic resin having a weight average molecular weight (Mw) of 20,000 to 40,000; 3 to 5 weight percent black pigment; 0.5 to 1.0 wt% pigment dispersant; 0.01 to 0.03% by weight of reaction catalyst; A black base mixture was prepared by mixing a black base and a curing agent containing 0.1 to 0.3% by weight leveling agent and 15 to 20% by weight of an organic solvent, diluting the black base mixture with thinner, and coating viscosity of 25 ° C. Preparing a coating composition for a black base by measuring from 12 to 16 seconds as measured by the Pod Cup No. 4;
3) forming a white primer layer by coating the coating composition for white primer of step 1) on the vehicle interior parts;
4) coating the coating composition for the black base of step 2) on the vehicle interior part in which the white primer layer of step 3) is formed, thereby forming a black base layer on the upper surface of the white primer layer; And
5) acryl comprising 25 to 30 wt% of 5 to 6 functional urethane acrylate oligomer, 5 to 10 wt% of bifunctional urethane acrylate oligomer, and 3 to 6 unsaturated groups on the upper surface of the black base layer of step 4) 3 to 7% by weight of the monomer, 3 to 7% by weight of the acrylate monomer containing two unsaturated groups, 2 to 4% by weight of the photoinitiator; 1-3% by weight of the UV stabilizer comprising; Coating the ultraviolet curable cree comprising a leveling agent 0.1 to 0.5% by weight and an organic solvent 45 to 55% by weight to form an ultraviolet cree coating layer, the coating method of the vehicle interior parts. The method of claim 1,
The white primer mixture of step 1) comprises a white primer and a curing agent in a weight ratio of 8: 1 to 12: 1. The method of claim 1,
The black base mixture of step 2) comprises a black base and a curing agent in a weight ratio of 8: 1 to 12: 1. The method of claim 1,
Step 3) is to form a white primer layer of 15 to 20㎛ thickness coating method of the vehicle interior parts. The method of claim 1,
Step 4) is to form a black base layer of 20 to 25㎛ thickness coating method of the vehicle interior parts. delete The method of claim 1,
The caprolactone-modified acrylic resin is an acrylic resin polymerized in methyl isobutyl ketone (MIBK) and propylene glycol monomethyl ether acetate, non-volatile content (Non-Volatile) 65 to 70%, acid value 5 to 6, hydroxyl value (OHV ) 55 to 60 and the glass transition temperature -5 to -10 ℃ coating method of the vehicle interior parts. The method of claim 1,
The acrylic resin having a glass transition temperature of 60 to 80 ° C. is an acrylic resin polymerized in butyl acetate (BuAc), and has a nonvolatile content of 45 to 55%, an acid value of 2.5 to 3.5, and a hydroxyl value (OHV) of 19 to 50. How to paint 20-car interior parts. The method of claim 1,
Acrylic resin polymerized in butyl acetate (BuAc) and methyl ethyl ketone (MEK) to have excellent adhesion to the polycarbonate is 40 to 60% of non-volatile content (Non-Volatile), acid value 2 to 3, hydroxyl value (OHV ) 14 to 15 and the coating method of the vehicle interior parts having a glass transition temperature of 80 to 90 ℃. delete The method of claim 1,
The high hardness acrylic resin is an acrylic resin polymerized in butyl acetate (BuAc), non-volatile content (Non-Volatile) 50 to 60%, acid value 4.5 to 5.5, hydroxyl value (OHV) 40 to 50 and glass transition temperature 60 to Coating method of vehicle interior parts which is 65 degreeC. The method of claim 1,
The caprolactone-modified acrylic resin is an acrylic resin polymerized in methyl isobutyl ketone (MIBK) and propylene glycol monomethyl ether acetate, non-volatile content (Non-Volatile) 65 to 70%, acid value 5 to 6, hydroxyl value (OHV ) 55 to 60 and the glass transition temperature -5 to -10 ℃ coating method of the vehicle interior parts. The method of claim 1,
The acrylic resin having a weight average molecular weight (Mw) of 20,000 to 40,000 is an acrylic resin polymerized from butyl acetate (BuAc) and methyl ethyl ketone (MEK), 40 to 60% of a non-volatile component (Non-Volatile), and an acid value of 2-3. And a hydroxyl value (OHV) of 14 to 15 and a glass transition temperature of 80 to 90 ° C. delete delete delete materials; And
An ultraviolet curable coating layer formed on the substrate,
The ultraviolet curable coating layer is a vehicle interior parts formed by the coating method of the vehicle interior parts according to claim 1. The method of claim 17,
The ultraviolet curable coating layer is a white primer layer formed in contact with the base layer;
A black base layer formed on an upper surface of the white primer layer; And
Vehicle interior parts comprising an ultraviolet curable cree layer formed on the upper surface of the black base layer.

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