JPH0768215A - Coating finishing method - Google Patents

Abstract

PURPOSE:To make fine texture, a pearl-like appearance and a feeling of flip-flop compatible with each other and thereby obtain a coating with a novel design by applying a base coating containing respective required contents of vehicle, specific glossing pigment and a coloring pigment as essential components, and then applying a clear coating. CONSTITUTION:A base coating contains a vehicle component, 1 to 80 pts.wt. of a glossing pigment with an average particle size of 5 to 25mum in a plate-like direction, which is composed of bismuth oxychloride crystalline particles, and 0.5 to 80 pts.wt. of a coloring pigment as essential components based on 100 pts.wt. of the vehicle component. This coating is applied to an object to be coated, and then, a clear coating is applied. The crystalline particles of bismuth oxychloride used have a monocrystal structure and are normally obtained by crystallizing bismuth trichloride in a hydrochloric acid solution. Therefore, compared to a mica pigment obtained by coating various metallic oxides onto mica powder which is obtained by crushing and classifying natural mica, this new coating shows a sharp viscosity distribution, satisfactory surface uniformity and high index of refraction, and further, easily presents a fine texture, a pearl- like appearance and a feeling of flip-flop.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel coating finishing method, and more particularly to a coating finishing method capable of efficiently imparting a pearly luster.

[0002]

2. Description of the Related Art Conventionally, as a paint finishing method for imparting a pearly luster to automobiles and metal parts, for example, (1) coating with at least one selected from oxides of titanium, iron, silicon and aluminum. "Pearl mica paint finishing method" (Japanese Patent Laid-Open No. 59-501954), which imparts pearl luster by using a base coat paint containing the above-mentioned mica, is further widely known. Further, (2) the hue changes depending on the viewing angle. Coating method for forming a pearl mica coating film on a color intermediate coating film in order to obtain a coating film having a flip-flop property (JP-A-63-215178) (3) Pearl mica coating on a color base coating film Coating finishing method for forming a film (JP-A 1-215380), (4) Coating finishing method for forming a pearl mica coating film on a metallic base coating film (JP JP) such 63-116784 is disclosed. However, each of these coating finishing methods for imparting a pearly luster has problems. That is, in the methods (1) to (4), the mica coated with at least one selected from oxides of titanium, iron, silicon and aluminum is
Due to the difference between the high refractive index of the oxide coating the surface and the refractive index of mica, it shows a unique pearl luster, but has the drawback of being inferior in hidden pay. To improve the hidden pay. When the proportion of mica pigment in the coating film is increased, the amount of the mica pigment from the coating film is increased and the finished appearance and the durability of the coating film are deteriorated. When a coloring pigment is used in combination, the pearlescent luster of the mica pigment is lowered and the color tone of the coating film is darkened, which inevitably results in a limited color gamut of low lightness and saturation. As described above, in the method of forming a coating film having a pearly luster by using mica coated with various oxides, the flaky shape obtained by crushing and classifying the natural raw material mica as the main raw material is used. At present, it is extremely difficult to make the particle size of mica uniform. Therefore, the pearl-like coating using scaly mica with an average particle size of 20 μm or more can strongly emphasize the flip-flop property, but on the other hand, it has the drawback of being inferior in the fineness of texture and appearance. The pearly coating using scaly mica having a diameter of 10 μm or less has a fine texture but has a drawback that it is difficult to obtain a desirable pearly feeling and flip-flop property.

[0003]

Under the circumstances described above, the present invention provides both the fineness of a pearly paint film using various oxide-coated mica and the pearly feeling and the flip-flop feeling, and The purpose of the present invention is to provide a coating finishing method that efficiently gives a coating film having a novel design property.

[0004]

As a result of intensive studies to achieve the above object, the present inventors have found that a vehicle component, a specific luster pigment and a coloring pigment are contained as essential components in predetermined proportions. It was found that the object can be achieved by applying the base coat paint to the object to be coated and then applying the clear paint, and based on this finding, the present invention has been completed. That is, the present invention relates to (A) a vehicle component and 100 parts by weight thereof,
A base coat paint containing (B) 1 to 80 parts by weight of a glossy pigment composed of bismuth oxychloride crystal particles in a plate-like average particle size of 5 to 25 μm and (C) 0.5 to 80 parts by weight of a pigment. It is intended to provide a coating finishing method which comprises coating an object to be coated and then applying a clear coating.

The present invention will be described in detail below. The vehicle component used as the component (A) in the base coat paint used in the method of the present invention is one for dispersing a gloss pigment of the component (B) and a color pigment of the component (C) to form a coating film. The kind is not particularly limited, and a known coating resin can be used. As the resin,
For example, a thermosetting resin formed by mixing a basic resin such as an acrylic resin, a polyester resin, a silicone resin, or a fluororesin with a cross-linking agent such as an amino resin or a blocked isocyanate compound can be preferably mentioned. Other than these, it is also possible to use a two-component polyurethane resin that is dried or cured at room temperature, a two-component silicone resin, or the like. The form of these paints is generally an organic solvent type, but may be a non-aqueous dispersion type, an aqueous solution type, an aqueous dispersion type, a solventless type, or a powder type. These vehicle components may be used alone or in combination of two or more. In the base coat paint, a luster pigment composed of bismuth oxychloride crystal particles is used as the component (B). The bismuth oxychloride crystal particles are single crystals which are usually obtained by crystallization by slowly adding water to an acidic bismuth trichloride-hydrochloric acid solution with stirring. Therefore, after crushing and classifying the natural mica,
Compared to mica pigments coated with various metal oxides, it has a sharp particle size distribution, and has surface uniformity and a high refractive index, so it has the advantage of giving a fine pearly feel and flip-flop feel. Have The bismuth oxychloride crystal particles are required to have a plate-like direction average particle size in the range of 5 to 25 μm.
The object of the present invention cannot be fully achieved.

In the present invention, the luster pigment of the component (B) may be used alone or in combination of two or more, and the blending amount thereof is the vehicle component of the component (A). It is selected in the range of 1 to 80 parts by weight, preferably 10 to 40 parts by weight, per 100 parts by weight. If this amount is less than 1 part by weight, it is difficult to obtain a flip-flop feeling, and if it exceeds 80 parts by weight, no improvement in pearly luster is observed for that amount. Further, in the base coat paint, a color pigment is used as the component (C). The color pigment is not particularly limited, and a color pigment conventionally used in conventional paints can be used. In the present invention, the color pigment as the component (C) may be used alone or in combination of two or more. In addition, the blending amount is 0.5 per 100 parts by weight of the component (A).
-80 parts by weight, preferably 5-40 parts by weight. If this amount is less than 0.5 parts by weight, the effect of adding the coloring pigment is not sufficiently exerted, and if it exceeds 80 parts by weight, the coating properties such as chipping property and moisture resistance tend to be deteriorated. In the base coat paint used in the method of the present invention, together with the above-mentioned luster pigment which is the component (B) and color pigment which is the component (C), an ordinary metal pigment, if necessary,
Mica pigments, extender pigments, and various types of additive components for paints can be added within the range that does not impair the object of the present invention.

The paint is used as an overcoat paint and can be directly applied to the surface of an object to be coated, but a conventionally known primer such as electrodeposition paint and a thermosetting paint are applied,
It is desirable to apply these coatings after curing.
It is preferable to use an atomization type coating machine as the coating machine,
It can be applied by a conventional method such as electrostatic coating or spray coating. The coating viscosity at the time of coating is adjusted in the range of 10 to 30 seconds, preferably 11 to 18 seconds (20 ° C.) with Ford cup # 4, and the coating film thickness is generally 5 to 30 μm based on the cured film thickness, preferably A range of 8 to 25 μm is suitable. It is possible to obtain a coating film having a glossy and excellent pearly luster by applying the clear coating material after the coating film is uncured or undried, or after being cured or dried. The clear paint used in the method of the present invention is a paint for forming a transparent coating film on the coating film surface of the base coat paint, and contains a vehicle component as a main component. As the vehicle component, those exemplified in the description of the base coat paint can be used. Further, a color pigment, a luster pigment, a metal pigment, a mica pigment, various additive components for paints, etc. may be added in a small amount to the clear paint, if necessary. The coating film thickness of the clear paint is generally 20 to 100 based on the cured film thickness.
Suitable is in the range of 30 μm, preferably 30-60 μm. In these steps, curing means three-dimensionally crosslinking and curing at room temperature or heating, and drying means simply evaporating a solvent to form a coating film.

[0008]

EXAMPLES The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto. The coating film performance was evaluated as follows. (1) Pearliness ◯: Remarkably pearlescent. Δ: There is a pearly luster. X: Little pearlescent feeling. (2) Transparency ◯: Clear color with transparency. Δ: Poor transparency. X: A cloudy color. (3) Flip-flop property (F / F property) O: Strong. Δ: Slightly present X: Poor (4) Finished appearance O: Smooth and no abnormality. Δ: There are fine protrusions on the surface. X: There are innumerable protrusions on the surface. Further, as a clear paint, an acrylic resin “Acridic 44-179” [manufactured by Dainippon Ink and Chemicals, Inc.,
Product name] 140 parts by weight and butylated melamine resin “Super Beckamine L-117-60” [Dainippon Ink and Chemicals, Inc., product name] 50 parts by weight of an organic solvent type containing a vehicle component as a main component A thermosetting paint was used.

Production Example 1 Production of base coat paints A-1 to A-9 containing luster pigments The components of the types and amounts shown in Table 1 were mixed and dispersed, and then 45 parts by weight of toluene, 30 parts by weight of xylene and butyl acetate. Base coat paints A-1 to A-9 were prepared by adjusting the viscosity to 14 seconds (Ford cup # 4/20 ° C) with a mixed organic solvent consisting of 15 parts by weight and 10 parts by weight of butanol.

[0010]

[Table 1]

[0011]

[Table 2]

[Note] 1) Radiant Pearl STL: manufactured by Marl, trade name, bismuth oxychloride having an average particle size of 13 μm 2) Heliogen Blue L-6900: manufactured by BASF, trade name, phthalocyanine system 3) Hoster Palm Violet RL-SP: Hoechst, trade name, dioxazine type 4) Chromophthal red A2B: Ciba Geigy, trade name, anthraquinone type 5) Perind Maroon R6436: Bayer, trade name, perylene type 6) Carbon black FW200B: Degussa, trade name, carbon type 7) Acridic 44-179: Dainippon Ink and Chemicals Co., Ltd., trade name, heating residue 50 wt% 8) Super Beckamine L-117-60: Dainippon Ink Kagaku Kogyo Co., Ltd., trade name, heating residue 60 wt%

Production Example 2 Production of base coat paints A-10 to A-14 containing luster pigment The bismuth oxychloride of the luster pigment base coat paint A-5 in Production Example 1 was replaced with A-10: titanium dioxide coated mica iridin 111WII.
(Merck, trade name, average particle size 6 μm), A-11: Titanium dioxide-coated mica iridin 121WII
(Merck, trade name, average particle size 10 μm), A-12: Titanium dioxide coated mica Iriodin 103WII
(Merck, trade name, average particle size 19 μm), A-13: Titanium dioxide coated mica Iriodin 215WS
Base coat paints A-10 to A in the same manner as A-5 except that the product name was changed to (Merck, trade name, average particle size 30 μm).
-13 was produced.

Examples 1 to 10 and Comparative Examples 1 to 4 A cationic electrodeposition coating [Aqua No. 4200: a registered trademark of NOF CORPORATION] on a zinc phosphate-treated steel sheet has a dry film thickness of about 20 μm. After electrodeposition coating and baking at 170 ° C for 20 minutes, an intermediate coating for automobiles [High Epico No.
100 sealer: registered trademark of NOF CORPORATION, spray-coated to a dry film thickness of about 40 μm, and 3 at 140 ° C.
A baking test plate was prepared for 0 minutes. Next, on this test plate,
The gloss pigment-containing paints and clear paints shown in Table 2
Coating was performed under the conditions shown in the table, and the performance of the resulting coating film was evaluated. The results are shown in Table 2. Under the baking conditions in Table 2, a indicates that the baking was performed at 140 ° C. for 30 minutes, and b indicates that the setting was performed at room temperature for 5 to 10 minutes without baking and then the process was moved to the next step.

[0015]

[Table 3]

As is clear from Table 2, Examples 1 to 1
At 0, there was also a transparent feeling, and the pearly luster was excellent in the flip-flop property and the finished appearance. On the other hand, in Comparative Example 1, the transparency and the finished appearance were excellent, but the pearliness and the flip-flop property were remarkably inferior. In Comparative Example 2, although the flip-flop property was excellent, the pearly feeling, the transparent feeling, and the finished appearance were slightly inferior. In Comparative Examples 3 and 4, the pearly feeling and the flip-flop property were excellent, but the transparency and the finished appearance were remarkably inferior.

[0017]

EFFECTS OF THE INVENTION According to the present invention, a glossy pigment composed of single crystal particles of bismuth oxychloride is contained in a base coat paint, whereby a coating having excellent performance that cannot be realized by various conventional metal oxide-coated mica. It is possible to obtain a film, that is, a coating film having a novel design which is excellent in fineness of texture and pearly feeling, flip-flop property, transparency and finished appearance.

Claims (1)

[Claims] 1. A vehicle component, and 1 to 80 parts by weight of a luster pigment having an average particle size in the plate-like direction of 5 to 25 .mu.m composed of (B) bismuth oxychloride crystal particles per 100 parts by weight and (C) coloring per 100 parts by weight of the vehicle component. A coating finishing method characterized by applying a base coat paint containing 0.5 to 80 parts by weight of a pigment as an essential component to an object to be coated, and then applying a clear paint.