JP2909874B2 - Paint composition and decorative metal plate coated with the paint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paint composition for producing a new decorative metal sheet having a concavo-convex pattern by baking and coating on a base metal sheet which has been subjected to a base treatment in advance, and the paint composition. The present invention relates to a decorative metal plate coated with. Further, the present invention relates to a decorative metal plate having an improved design by providing a base paint layer and a printed layer between a raw metal plate and the coating film.

[0002]

2. Description of the Related Art A conventional decorative metal plate has been prepared by applying a base paint to a base metal plate which has been subjected to a base treatment in advance, printing the surface of the base metal plate, and then printing a clear paint to protect the surface. However, since the surface of the coating film was smooth, there was a defect that the three-dimensional appearance was poor and the coldness unique to a metal plate was present.
For this reason, a device has been devised to give a three-dimensional feeling and a thick feeling by embossing the decorative metal plate as a post-processing. Also, silicone-based auxiliaries have been used for forming a three-dimensional pattern in a painting process. However, embossing increases the number of manufacturing steps. Silicone auxiliaries fulfill the original purpose of forming uneven patterns, but manufacture of paints,
Sufficient cleaning in the painting and other processes is difficult and likely to be an impurity, often causing defects such as repelling in the subsequent production and painting of the paint. For this reason, there is a concern about the high cost of a series of steps of manufacturing, coating, and cleaning of the apparatus, and a paint that does not use a silicone-based auxiliary agent has been demanded.

[0003]

DISCLOSURE OF THE INVENTION The present invention relates to a paint composition for a decorative metal sheet which forms an uneven pattern without using a post-processing step and a silicone-based auxiliary as described above, and a baking coating of the paint composition. The object of the present invention is to provide a decorative metal plate subjected to the following.

[0004]

Means for Solving the Problems To solve the above problems, the present invention relates to a method of manufacturing a metal plate which has been subjected to a base treatment in advance.
A resin obtained by modifying a polyester resin with a silicone resin and having a weight average molecular weight of about 2,000 to 10,000 as a binder, an amide aggregate having a melting point of 110 to 170 ° C. and an average particle size of 15 to 200 microns is used. An uneven pattern is formed by baking and coating a coating composition characterized by containing 0.1 to 5% in the coating composition. Also, after baking a base paint on the material metal plate, printing on it by gravure offset or other method, and then baking and coating the above paint composition, forming an uneven pattern with further design properties Obtained decorative metal plate.

[0005] As the material metal plate, various types of metal plates conventionally used for pre-coated steel plates, such as a zinc iron plate, a zinc-aluminum alloy-plated steel plate, a stainless steel plate, and an aluminum plate, can be used. Also, for the base treatment, various conventional treatment agents suitable for various materials can be applied.

In the coating composition of the present invention, a resin obtained by modifying a polyester resin, which has good workability and is suitable for a precoated metal plate, with a silicone resin is used as a binder. Taking the case of a polyester resin as an example, a resin composed of a polyhydric alcohol such as neopentyl glycol and ethylene glycol and a polybasic acid represented by isophthalic acid, tertiary phthalic acid, adipic acid and the like is used. As the silicone resin-modified polyester resin, an "oil-free alkyd resin" such as "Beccolite" manufactured by Dainippon Ink and Chemicals, Inc. is suitably used. As the curing agent, methylated melamine, block urethane and the like can be used. The weight average molecular weight of these binders is about 2000 to 1000
A range of 0 is preferred. If the molecular weight is less than 2,000, the strength as a coating film is insufficient, and if it is more than 10,000, curing at the time of baking is slow, and the uneven pattern becomes unclear.

[0007] Examples of aggregates of amides to be included in the coating composition together with the resin in order to obtain an uneven pattern include saturated fatty acid monoamides, unsaturated fatty acid monoamides, saturated fatty acid bisamides, unsaturated fatty acid bisamides, aromatic bisamides and the like. Preferably, methylene bisamide or ethylene bisamide has a melting point of about 140 ° C. and is particularly preferably used. The melting point of amides is 1
10-170 degreeC is preferable, and the range of 120-150 degreeC is more preferable. When the melting point is lower than about 110 ° C. or higher than about 170 ° C., the balance between the evaporation of the solvent and the melting of the amide during baking cannot be balanced, so that the uneven pattern becomes unclear and the commercial value decreases. Further, it is preferable to use amides having an average particle size of 15 to 200 μm, more preferably 60 to 200 μm.
A range of 120 microns is good. When the particle size is about 10 microns, the irregular pattern becomes small. When the particle size exceeds 200 microns, the irregular pattern becomes unclear, and the commercial value decreases in any case.

The amides described above are added to the coating composition in a weight ratio of about 0.1 to 5%, more preferably about 0.5 to 2%, and sufficiently dispersed. If it is less than 0.1%, irregularities are scattered, and if it exceeds 5%, the irregularities interfere with each other and the pattern becomes unclear. Isobutanol as a dispersion medium,
Alcohol such as normal butanol, boiling point of 120 to 2
Aromatic solvents, esters and ketones at about 20 ° C. can be used.

When the coating composition is baked on the above-mentioned material metal plate at a reaching plate temperature of 200 to 230 ° C. so as to have a film thickness of about 5 to 20 μm, a coating film having an uneven pattern can be obtained. it can.

[0010] The mechanism for forming the concavo-convex pattern is formed by the difference between the surface tension of the amides after dissolution and the surface tension of the resin binder. Therefore, as the difference between the two is greater, the concavities and convexities are clearly seen. Therefore, the weight average molecular weight of the resin binder is preferably about 2,000 to 10,000.
The curing agent is preferably a quick-drying agent such as methylated melamine or block urethane. This is useful for fixing the shape quickly when the wet coating film becomes uneven due to the difference in surface tension.

In addition to coating directly on the material metal plate, a base paint is baked on the material metal plate which has been subjected to a pre-treatment such as a chemical conversion treatment, and gravure offset or another method is applied thereon. After printing, by baking and coating the coating composition, or by baking and coating a base coating on a material metal plate, and baking and coating the coating composition thereon, by further providing a printing layer In addition, it is possible to form a concavo-convex pattern provided with a design property.

As the base coating, a coating containing a rust preventive pigment may be used. Alternatively, a base paint containing no rust preventive may be used after a primer containing a rust preventive has been applied. Further, in the case of a stainless steel material or the like, a base paint containing no rust inhibitor can be used. As a resin composition of the base coating material, a polyester resin is mainly used as a main resin, and a methylated melamine or a block urethane resin is mainly used as a curing agent. It is necessary to consider interlayer adhesion between the ink and the coating layer. For example, in baking, it is necessary to avoid complete curing and to maintain only the primary curing in order to ensure adhesion to the upper layer coating film. The specific baking temperature is preferably about 180 to 210 ° C. in the reached plate temperature.

As a printing method, printing using a gravure roll or flexographic printing can be applied, and it can be used both online and offline. As the pattern, there are various patterns such as an abstract pattern and a stone pattern in addition to the woodgrain. As the ink, an oil-free alkyd resin or an ink to which various colored pigments and extenders are added using an acrylic resin as a binder is used. Solvents and auxiliaries are added to the ink to give printability.

[0014] By adding a matting agent to the coating composition, a low gloss coating film can be realized. As a matting agent,
Synthetic silica having a particle size of about 0.2 to 20 microns is suitable, and 0.1 to 5% is desirably added to the coating composition. Particle size 10
In the case of a synthetic silica of about 20 μm, the unevenness of the coating film can be further enhanced. In addition, a color paint obtained by adding 0.1 to 5% of a color pigment to the paint composition can be applied on the printing of the stone pattern and the lysine-like abstract pattern. The quail egg pattern and the granite pattern can be reproduced by the color scheme of the coloring paint. Since the colored paint has a repellent pattern and a non-uniform film thickness, the degree of concealing the color tone of the base slightly varies depending on the location, and it is possible to give a design that gives the impression of multicolor printing.

[0015]

The present invention will be described below in detail with reference to examples. All parts and percentages in the examples are on a weight basis.

The coating composition of the present invention was prepared by a conventional method using the compositions shown in Tables 1 and 2. The coating materials shown in Tables 1 and 2 are applied to a 0.4 mm thick aluminum-zinc alloy-plated steel plate with a bar coater so as to have a thickness of 10 μm. Plate temperature)
Baked in. The concavo-convex pattern of the completed coating film was visually determined according to the following criteria. The results are shown in the same table. ◎: A large size uneven pattern is clearly formed. : The uneven pattern is clearly formed. Δ: The size of the uneven pattern is small and not suitable for practical use. ×: Uneven pattern is unclear.

As a material metal plate, a 0.4 mm thick aluminum-zinc alloy-plated steel plate subjected to a coating type chromate treatment,
The base paint having the composition shown in Table 3 was coated with a bar coater to a film thickness of 15
It was applied to a micron size and baked at 200 ° C. (maximum reached plate temperature). Next, using an ink having a composition shown in Table 4, a wood grain pattern was printed by gravure offset and lightly dried.

Various aggregate-containing paints having the compositions shown in Tables 1 and 2 were applied to the printed test metal pieces obtained above using a bar coater so as to have a film thickness of 10 μm. Baked.

[0019]

[Table 1]

[0020]

[Table 2]

* 1 to * 6 in Tables 1 and 2 indicate the following chemicals. * 1: Becolite 47-335 oil-free alkyd resin (molecular weight 2000), non-volatile content 60% * 2: Beckolite M-6401 oil-free alkyd resin (molecular weight 5000), non-volatile content 50% * 3: Beccolite 57-206 oil-free Alkyd resin (molecular weight 10,000) nonvolatile content 40% * 4: Beccolite M-6801 oil-free alkyd resin (molecular weight 15000) nonvolatile content 40% or more, manufactured by Dainippon Ink and Chemicals, Inc. * 5: Methylated melamine as a curing agent 15 parts (nonvolatile content 60%), I-butanol # 1, sorbeso # 10
20 parts of a mixed solvent of 0 ‥ 2 and cyclohexanone ＊ 1 * 6: Monostearic acid amide having a melting point of 100 ° C .: bisstearic acid amide having a melting point of 140 ° C.

[0022]

[Table 3]

[0023]

[Table 4]

As shown in Examples 1 to 3 in Table 1, the resin has a weight average molecular weight of about 2,000 to 10,000, a melting point of amide of about 140 ° C., and an average particle size of about 60 to 120 μm. And Table 2
As shown in Example 4, it can be seen that an uneven pattern can be clearly formed even with an average particle size of about 30 μm. The formation of the concavo-convex pattern itself does not depend on the presence of the base coat and the print layer on the material metal plate, but the base coat or the case where the base coat and the print layer are provided can further enhance the design. Needless to say.

As shown in Comparative Example 1 in Table 1, when the weight average molecular weight of the resin binder exceeds about 10,000, the curing reaction at the time of baking is slow, and the uneven pattern becomes unclear. Table 2
As shown in Comparative Example 2, when the average particle size of the amide is about 10 μm, the irregularity pattern is small and the commercial value is significantly reduced. Further, when the melting point of the amides is about 100 ° C., as shown in Comparative Example 3, the uneven pattern becomes unclear and the commercial value is also lowered.

[0026]

According to the present invention, a polyester and / or acrylic resin or any of them is modified with a silicone resin on a metal plate having a weight average molecular weight of 2,000 to 2,000.
A resin in the range of 10,000 is used as a binder and the melting point is 11
An amide aggregate having a temperature of 0 to 170 ° C. and an average particle size of 15 to 200 μm is contained in the coating composition in an amount of 0.1 to 5 μm.
By baking and coating a paint characterized by containing%, an uneven pattern can be obtained only by coating without performing a post-process such as embossing. Further, by using amides without using a silicone-based auxiliary agent, the production process of the coating material and the washing process in the coating process can be significantly simplified. Further, by interposing a base coating film and a printing layer, a decorative metal plate having a three-dimensional pattern with further improved design can be obtained.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI C09D 133/00 C09D 133/00 167/00 167/00 (72) Inventor Jun Furukawa 3-30-16 Sakashita, Itabashi-ku, Tokyo ( 72) Inventor Akio Tashiro 4-1-1, Minamihonmachi, Chuo-ku, Osaka-shi, Osaka Inside Yodogawa Steel Works, Ltd. (58) Field surveyed (Int.Cl. ⁶ , DB name) C09D 5/28 C09D 7/12 C09D 133/00-133/16 C09D 167/00-167/08

Claims (5)

(57) [Claims] 1. Amides having a melting point of 110 to 170 ° C. and an average particle size of 15 to 200 μm, wherein a resin obtained by modifying a polyester resin with a silicone resin and having a weight average molecular weight in the range of 2,000 to 10,000 is used as a binder. A coating composition comprising 0.1 to 5 % by weight of the above-mentioned aggregate in the coating composition. 2. The coating composition according to claim 1, wherein the amide is methylene bisamide or ethylene bis amide. 3. The method according to claim 1, wherein the base metal plate is preliminarily subjected to a base treatment.
A decorative metal plate obtained by baking and coating the coating composition according to claim 1. 4. The decorative metal plate according to claim 3, wherein the paint composition is baked and applied after providing a base paint layer or a base paint layer and a print layer on the material metal plate. 5. The decorative metal plate according to claim 3, wherein a base paint is baked on the material metal plate, and the paint composition is baked and coated thereon, and further provided with a printed layer.