JP3464962B2 - Printed metal sheet with excellent scratch resistance - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to a full-color advertising billboard,
Used for decorative interior materials, elevator door materials, decorative flooring materials, outer panels for home appliances, outer panels for furniture, etc., various printed patterns are applied, and printed metal plates with excellent scratch resistance and abrasion resistance. Regarding

[0002]

2. Description of the Related Art When a printed coated metal plate is produced by using a sublimable dye, the sublimable dye is printed on the top clear layer of the coated metal plate by a printing method such as offset, silk, gravure or transfer, and then sublimated. Heat treatment is applied to penetrate the clear coating into the coating film. For pattern printing using sublimable dyes,
A method in which a transfer sheet is brought into contact with a coating film of a curable synthetic resin and heated (Japanese Patent Application Laid-Open No. 51-24313), a printing layer is formed on a coated metal plate by transfer printing using a sublimable dye, and then the surface is formed. To form a top coating film, and then subjecting the top coating film to a sublimation dye from the inside to perform a heat treatment (JP-A-54-104907), to form a primer coating film and a colored top coating film. Method of permeating a sublimable ink into the coating film of a prepainted metal plate (JP-A-7-319)
31), a method of infiltrating a sublimation type colorant into the opaque resin layer provided on the surface of a metal plate (JP-A-7-
No. 102733) is known.

However, although a normal clear coating film is smooth and excellent in glossiness and image clarity, it is likely to have flaws and has insufficient flaw resistance and abrasion resistance. For this reason, it is difficult to apply it to a site having a significant flaw such as a flooring material or a table top plate, and it is also a drawback that it requires careful handling. The scratch resistance and abrasion resistance of the coating film are
It is improved by the addition of inorganic aggregate. As this type of coating material, powder coating material having 5 to 70% by mass of fibrous glass added to improve abrasion resistance and scratch resistance (JP-A-48-
No. 66640), a glass flake having a thickness of 3 μm or less that passes through a 150-mesh screen is blended in an amount of 0.3 to 50% to improve the wear resistance and scratch resistance of the precoated steel sheet (JP-A-51-8128). Gazette), an average particle size of 3 to 30 relative to 100 parts by weight of the solid content of the color-developing agent in the coating film.
Acrylic resin-based paints (Japanese Patent Laid-Open No. 8-183926) in which 5 to 60 parts by weight of an inorganic aggregate of μm are mixed are known. However, since all of the coating films have poor transparency, the design properties of the underlying metal or the undercoating film cannot be fully utilized.

The scratch resistance and abrasion resistance are also improved by irradiation with an electron beam as seen in an electron beam curing type acrylic resin coating (Japanese Patent Publication No. 55-5422 and Japanese Patent Publication No. 56-8070). Gazette, JP-A 1-229622, JP-A-2-242863). The electron beam-irradiated coating film has a pencil hardness of 9H or more, and thus is modified into a coating film having excellent abrasion resistance, scratch resistance, and stain resistance. However, the processability of the coating film is low, an expensive coating material is required, and electron beam irradiation equipment is required for curing the coating film, resulting in high manufacturing cost. Another drawback is that the coating film cured by electron beam irradiation is inferior in weather resistance to the thermosetting coating film.

A full-color printed metal plate is manufactured by a simple small-lot post-processing by applying a film, in addition to the use of a sublimable dye. However, the obtained full-color printed metal plate has a problem in long-term use because the end surface of the film is easily peeled off. If the hardness of the film is increased, the scratch resistance is improved, but the work of attaching the film to the metal plate becomes difficult.
Further, the full-color printed metal plate has a surface appearance depending on the texture of the film, and it is difficult to develop a metallic feeling.

[0006]

The print pattern developed by using the sublimable dye has a limited coloring density because the sublimation dye has a low hiding property. Further, there is a phenomenon that the sublimation dye excessively moves due to heat at the time of transfer and penetrates into the undercoat coating film, or part of the sublimation dye returns to the transfer sheet side.
As a result, especially when characters or the like are printed, a printed pattern with an impression lacking in sharpness is likely to be provided.

[0007]

The present invention has been devised in order to solve such problems, and by forming a clear topcoat film containing silica, a base metal or an undercoat film can be formed. It is an object of the present invention to provide a printing-coated metal plate that makes full use of design properties, has a high coloring concentration of a sublimable dye, is capable of full-color printing, and has improved scratch resistance and abrasion resistance.

In order to achieve the object, the printed metal plate of the present invention has a film thickness of 5 to 40 in which silica having an average particle size of 0.5 to 8 μm is dispersed in an amount of 1 to 10% by mass based on the non-volatile component of the paint.
It is characterized in that a clear topcoat film having a μm, 60 ° gloss value of 10 to 75 is provided on the surface layer, and a sublimable dye permeates into the topcoat film to give a print pattern. It is preferable to blend a triazine-based UV absorber and / or a benzotriazole-based UV absorber into the clear top coating film.

[0009]

The present inventors conducted various investigations and studies on the excessive migration of the sublimable dye, which tends to occur when a printed pattern is applied with the sublimable dye. When a transfer sheet printed with a sublimable dye is superposed on a coated metal plate and heat-treated, the sublimated dye excessively moves to the undercoat coating film, or a part of the dye returns to the transfer sheet side. From the results of studies conducted by the present inventors, it has been found that excessive migration of the sublimable dye is suppressed by dispersing silica in the coating film. Silica in the coating film not only suppresses excessive migration of the sublimable dye, but also forms fine voids inside and on the surface of the coating film. Due to the formation of the voids, the sublimable dye is more likely to permeate in the film thickness direction than in the coating film surface direction, and the coloring density is increased. As a result, a printed pattern having a high sharpness and a strong impression is developed.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION A printed metal plate according to the present invention is provided with a base coat layer 2 and a primer layer 3 on the surface of a base metal plate 1 as shown in FIG. 4 is forming. As long as the surface layer has the clear top coat film 4, the clear top coat film 4 is provided via the base metal layer (a), the base coat layer 2 and the primer layer 3 on which the clear top coat film 4 is provided. It may be either the coated metal plate (b) or the coated metal plate (c) in which the clear top coating film 4 is directly formed on the base metal plate 1. The base coat layer 2 is not limited to a white color, and those having other color tones including a clear coating film can also be used. The color tone of the clear top coating film 4 is preferably as transparent as possible so that the metallic luster of the base metal plate 1 or the design properties of the base coat layer 2 and the primer layer 3 are sufficiently exhibited.

The base metal plate 1 is not particularly limited in material, and various metal plates such as cold rolled steel plates, various plated steel plates, stainless steel plates, copper plates and aluminum plates are used. A metal plate having a metallic luster, such as a stainless steel plate, an aluminum plate, and a copper plate, is preferable in order to develop the original design feeling of the metal. The base metal plate 1 is subjected to chemical conversion treatment such as mechanical polishing, pickling, phosphate treatment, chromate treatment, etc. according to the type and surface condition of the metal plate prior to the application of the undercoat paint or the topcoat paint, and the coating film Adhesion can be improved. The base coat layer 2 and the primer layer 3 are formed on the pretreated base metal plate 1 by a conventional method.

A clear top coat film 4 having a film thickness of 5 to 40 μm is formed on the base metal plate 1, the base coat layer 2 or the primer layer 3. If the thickness of the clear top coating film 4 is less than 5 μm, sufficient abrasion resistance cannot be obtained. On the other hand, in the case of a thick film having a thickness of more than 40 μm, the solvent remaining in the coating film is rapidly vaporized during baking, which may cause a pinhole-shaped coating film defect called “armpit”. If the clear top coat film 4 becomes too thick, the transparency is impaired, and the metallic luster of the base metal plate 1 or the designability of the base coat layer 2, the primer layer 3 and other undercoat films cannot be sufficiently exhibited.

The thickness of the clear top coating film 4 is preferably set in the range of 10 to 25 μm from the balance of designability and wear resistance. In applications such as flooring materials where a large amount of wear is expected due to use, it is possible to further form a clear coating film as an undercoat coating film in consideration of the wear. When a hardening agent such as melamine, urea, or isocyanate is added to the clear top coating film 4, the coating film hardness increases.

The clear top coat 4 has an average particle size of 0.5.
~ 8 μm silica is dispersed. By adding silica having an average particle size of 0.5 μm or more, a clear top coating film 4
Has a pencil hardness of F or more, and sufficient scratch resistance and abrasion resistance are secured, and the coloring density of the sublimable dye is improved. However, when silica having an average particle size of more than 8 μm is dispersed in the clear topcoat coating film 4, the coating film is easily cracked during bending of the coated metal plate, and the coating film is likely to drop due to abrasion. Silica with a large particle size has a clear top coat 4
It tends to impede the permeation of the sublimable dye with respect to, and to reduce the color density.

Silica is blended in the clear top coating film 4 in a proportion of 1 to 10% by mass. Silica content is 1% by mass
If it is less than 1, sufficient scratch resistance cannot be obtained and the gloss value is 75.
The surface condition is such that scratches are more noticeable. On the contrary, when the amount of silica is more than 10% by mass, the gloss value is less than 10 and the transparency of the coating film is impaired. As a result, the base metal plate 1
The metallic luster or the undercoating coating film of the base coat layer 2, the primer layer 3 and the like cannot be sufficiently exhibited. Also,
If an excessive amount of silica is blended, the coating film will be easily cracked when the coated metal plate is bent. The gloss value of the clear top coating film 4 is 40 when the metal gloss of the base metal plate 1 is used.
When the undercoating film of the base coat layer 2 and the primer layer 3 is formed in the range of 60 to 60, the flaw is less noticeable 10 to 3
It is preferable to adjust the range to 0. The influence of silica on the improvement of the coloring concentration of the sublimable dye becomes remarkable at a blending amount of 1% by mass or more, and at 10% by mass or more, the concentration becomes almost constant regardless of the blending amount of silica.

The paint used for forming the clear top coat film 4 is not particularly limited as long as it is a resin that is dyed well by receiving the sublimable dye transferred from the transfer sheet. Also, the heating temperature for transferring the print pattern is 1
It is preferable to use a thermosetting resin that does not soften significantly at 50 to 200 ° C. The resin having good heat resistance effectively suppresses the reduction of the surface gloss of the printed and coated metal plate after the printed pattern is formed by thermal transfer.

Specifically, polyvinyl alcohol, polyvinyl butyral, polyvinyl acetal, polyvinyl acetate, polyvinyl chloride, polyvinyl pyrrolidone, vinyl resins such as polystyrene, polymethyl (meth) acrylate, polybutyl (meth) acrylate, polyacrylamide, Acrylate resins such as polyacrylonitrile, polyester resins, polycarbonate resins, polyurethane resins, polyamide resins, urea resins, polycaprolactone resins, polyarylate resins, polysulfone resins, silicone polyester resins, epoxy resins, etc., and copolymers of these resins or The mixture is used as a dyeable resin coating for clear topcoat 4. Among them, the polyester resin is excellent in dyeability to a sublimable dye, and the storage stability of the obtained printing design is also good. Therefore, it is preferable to include the polyester resin as one component of the dyeable resin coating material.

When an ultraviolet absorber is added to the clear top coating film 4, a decrease in adhesion and discoloration due to the transmission of sunlight, ultraviolet rays, etc. are suppressed. The ultraviolet absorber contained in the top coating film 4 is required to have excellent heat resistance, sublimation resistance and solubility. Above all, it is preferable to exhibit heat resistance such that the weight loss at 300 ° C. is 10% by mass or less under heating conditions in an air atmosphere at a heating rate of 5 ° C./min. Ultraviolet absorbers that satisfy the required characteristics include benzotriazole type and triazine type. Preferably, a triazine type alone or a mixture of a triazine type and a benzotriazole type is added to the clear top coat film 4 coating material. Further, a hindered amine light stabilizer can be blended in a proportion of 0 to 3.0% by mass.

The benzotriazole-based UV absorber includes octyl-3- [3-t-butyl-5- (2H-benzotriazol-2-yl) -4-hydroxyphenyl] propinate (TINUVIN 384 manufactured by Ciba Geigy). , 2- [2-hydroxy-3,5-bis (α, α'dimethylbenzyl) phenyl]
-2H-benzotriazole (TINUVI manufactured by Ciba Geigy)
N 900), a condensation product of methyl-3- [3-t-butyl-5- (2H-benzotriazol-2-yl) -4-hydroxyphenyl] propinate and polyethylene glycol (molecular weight approx. 300) (Ciba Geigy) TINUVIN 1130), 2- [2 '
-Hydroxy-3 '-(3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl] -benzotriazole (Viosorb 590 manufactured by Kyodo Chemical Co., Ltd.) and the like can be mentioned.

Examples of the triazine-based ultraviolet absorber include
2- [4-[(2-hydroxy-3-didecyloxypropyl)
-Oxy] -2-hydroxyphenyl] -4,6-bis (2,4-
Dimethylphenyl) -1,3,5-triazine and 2- [4-[(2-
Hydroxy-3-tridecyloxypropyl) -oxy]
2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl-1,3,5-triazine mixture (TINUVIN 400 manufactured by Ciba-Geigy), etc. These UV absorbers may be used alone. It can also be used as a mixture of two or more kinds.
The amount of UV absorber blended is 1 with respect to the non-volatile components of the paint.
It is preferably adjusted to -18% by mass. When the amount is more than 18% by mass, the stain resistance, workability, and appearance of the coating film tend to deteriorate. In addition, coloring of the coating film due to the ultraviolet absorber is also observed.

In order to further improve the light resistance of the clear top coating film 4, it is preferable to add a hindered amine light stabilizer in an amount of 3.0% by mass or less based on the non-volatile components of the paint, if necessary. Examples of the hindered amine light stabilizer include the following substances. Bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate (Sankyo Co., Ltd.
SANOL LS770), bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate (SANOL LS76 manufactured by Sankyo Co., Ltd.)
5), 1- [2- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-
Di-t-butyl-4-hydroxyphenyl) probionyloxy] -2,2,6,6-tetramethylpiperidine (SANOL LS2626 manufactured by Sankyo Co., Ltd.), 4-benzoyloxy-2,2,
6,6-Tetramethylpiperidine (SANOL manufactured by Sankyo Co., Ltd.
LS744), 8-Acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro [4,5] decane-2,4-
Dione (SANOL LS440 manufactured by Sankyo Co., Ltd.), 2- (3,5-di-t-hydroxybenzyl) -2-n-butylmalonate bis
(1,2,2,6,6-pentamethyl-4-piperidyl) (TINUVIN 144 manufactured by Ciba Geigy), bis (2,2,6,6-
Tetramethyl-4-piperidyl) ester (TINUVIN 780FF from Ciba Geigy), a polycondensate of dimethyl succinate and 1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine (Ciba Geigy) Company TINUVI
N 622LD), poly [[6- (1,1,3,3-tetramethylbutyl))
Amino-1,3,5-triazine-2,4-diyl] [(2,2,6,6-
Tetramethyl-4-piperidyl) imino] hexamethylene
[(2,2,6,6-Tetramethyl-4-piperidyl) imino]]
(CHIMASSORB 944LD manufactured by Ciba Geigy), N, N'-bis
(3-Aminopropyl) ethylenediamine and 2,4-bis [N-
Butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine polycondensate (Ciba Geigy CHIMASSORB 119FL), bis (1 , 2,
2,6,6-Pentamethyl-4-piperidyl) sebacate (TINUVIN 292 manufactured by Ciba Geigy), bis (1-octaoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate (TINUVIN 123 manufactured by Ciba Geigy) , HA-70G (manufactured by Sankyo Co., Ltd.), ADEKA STAB LA-52, ADEKA STAB LA-
57, ADEKA STAB LA-62, ADEKA STAB LA-63, ADEKA STAB LA-67, ADEKA STAB LA-68, ADEKA STAB
LA-82, ADEKA STAB LA-87 (manufactured by Asahi Denka Kogyo Co., Ltd.)

These light stabilizers may be used alone or in combination with 2.
It is also possible to use a mixture of two or more species. Even if the light stabilizer is blended in an amount of more than 3.0% by mass, the effect of improving the light resistance is saturated and the improvement commensurate with the increase in the amount is not seen, but rather the coating appearance tends to deteriorate. The light stabilizer is preferably 0.
It is mixed in the range of 5 to 1.5% by mass. The transparent or semi-transparent top coat film 4 is formed through the base coat layer 2 (see FIG.
a), via the base coat layer 2 and the primer layer 3 (FIG. 1b), or directly on the base metal plate 1 (FIG. 1c). In any case, the color tone of the base metal plate 1 and the base coat layer 2 becomes a ground pattern, and a printed and coated metal plate having a unique depth feeling utilizing the texture of the base material can be obtained.

After forming the clear topcoat coating film 4, heat treatment is carried out with the transfer sheet being in contact with the clear topcoat coating film 4 on the surface layer. The sublimation dye contained in the transfer sheet is sublimated by the heat treatment, and the sublimation dye permeates in the thickness direction of the clear top coat film 4 as shown in FIG. as a result,
The sublimable dye dyeing layer 5 dyed substantially uniformly in the thickness direction is formed on the clear topcoat coating film 4, and a printed pattern rich in three-dimensional effect is obtained. The transfer sheet can be produced by gravure printing, offset printing, or screen printing. For small-lot printing, an electrophotographic method using computer graphics that does not require a plate making process, an electrostatic recording method, an inkjet method, a thermal transfer method, or the like can be used.

The sublimable dye is a dye which can be transferred by a phenomenon such as sublimation or volatilization when heated. In the present specification, “sublimation” is used in the sense that it also includes volatilization from the liquid layer. As the sublimable dye, disperse dyes such as quinophthalone derivatives, anthraquinone derivatives, and azo dyes are preferably used. Further, sublimation dyes conventionally used in sublimation heat transfer, sublimation transfer printing and the like are used for printing the clear top coat film 4 without any particular limitation.

Among sublimable dyes that can be used, yellow dyes include Kayacet Yellow AG and Kayaset Yellow TD.
N (above, Nippon Kayaku Co., Ltd.), RTY 52, Dianix Yel
low5R−E, Dianix Yellow F3G−E, Dianix Brilliant Y
ellow 5G-E (above, Mitsubishi Chemical Corporation), blast
Yellow 8040, DY108 (above, Arimoto Chemical Co., Ltd.), Su
mikaron Yellow EFG, Sumikaron Yellow E-4GL (above, Sumitomo Chemical Co., Ltd.), FORON Brilliant Yellow S
GGLPI (manufactured by Sand), PS Yellow GG (above, manufactured by Mitsui Toatsu Dye Co., Ltd.), etc.

For magenta sublimation dyes, Kayaset Re
d 026, Kayaset Red 130, Kayaset Red B (above, manufactured by Nippon Kayaku Co., Ltd.), Oil Red DR-99, Oil Red DK-99 (above, manufactured by Arimoto Chemical Co., Ltd.), Diacelliton Pink B (above, Mitsubishi Chemical) Ltd.), Sumikaron Red E-FBL (above, Sumitomo Chemical Co., Ltd.), Latyl Red B (above, DuPon
t company), Sudan Red 7B (above, BASF company), Resolin
Red FB, Ceres Red 7B (above, manufactured by Bayer) and the like.

For the cyan sublimation dye, Kayalon Fast
Blue FG, Kayalon Blue FR, Kayacet Blue 136, Kayac
et Blue 906 (Nippon Kayaku Co., Ltd.), Oil Blue
63 or above, Arimoto Chemical Co., Ltd., HSB9, RTB 31 (or above, Mitsubishi Chemical Co., Ltd.), Disperse Blue # 1 (or above, Sumitomo Chemical Co., Ltd.), MS Blue 50 (or above, Mitsui Toatsu Dyestuff Co., Ltd.) Company), Ceres Blue GN (above, Bayer), Duranol Brilliant Blue 2G (above, ICI).

The sublimable dyes for each color may be used alone or in admixture of two or more. The black color tone is obtained by appropriately mixing sublimation dyes for yellow, magenta and cyan. As the sublimable dye having a color tone other than yellow, magenta and cyan, a dye having a sublimation temperature of 60 ° C. or higher is used. When the sublimation dye is selected, the higher the sublimation temperature, the higher the molecular weight, and therefore the excellent light resistance and heat resistance are imparted to the clear top coat film 4.

According to this method, a desired printed pattern can be easily provided when needed, so that it is possible to produce a small lot of design steel sheets provided with various patterns corresponding to various needs. Moreover, since it is not necessary to stock the designed steel plates with a predetermined print pattern in stock, the inventory burden is reduced. Further, since the sublimable dye 5 does not exist alone between the clear top coating film 4 and the base metal plate 1, delamination unlike the conventional laminated steel plate does not occur.

[0030]

Example 1 A clear top coat film 4 was directly applied to the base metal plate 1.
Manufacture of formed and printed metal plates (Invention Examples 1 to 6, Comparative Examples 1 to 4, 7 to 12: Fig. 1c)
A SUS304HL stainless steel plate having a plate thickness of 0.5 mm was degreased, subjected to a surface conditioning treatment, and subjected to a coating type chromate treatment, and then a clear topcoat paint was applied at an application amount such that a dry film thickness was 12 μm. As a clear top coating, 0.5% silica having an average particle size of 0.3 to 12 μm based on the nonvolatile components of the coating is used.
A polyester coating containing -15% by mass and 3% by mass of a triazine-based ultraviolet absorber (TINUVIN400 manufactured by Ciba-Geigy Co., Ltd.) was used. Plate temperature 230
A semi-transparent clear top coat film 4 was formed by baking at 0 ° C. for 1 minute.

Clear topcoat over basecoat layer 2
Production of Printed Metal Plates Forming Film 4 (Invention Examples 7 to 12 and Comparative Examples 5 to 8: FIG. 1a) A hot-dip Zn-plated steel sheet having a thickness of 0.5 mm was degreased, surface-conditioned, and coated chromate-treated. After that, a white polyester-based resin coating material was applied in an application amount such that the dry film thickness was 15 μm, and baked at a plate temperature of 220 ° C. for 1 minute to form a white base coat layer 2. Next, 0.5% silica having an average particle size of 0.3 to 12 μm based on the nonvolatile component of the coating material is used.
-15% by mass and 3% by mass of a triazine-based UV absorber (TINUVIN400 manufactured by Ciba-Geigy Co., Ltd.) in a semi-transparent polyester-based top coating composition is applied on the base coat layer 2 at a coating amount such that the dry film thickness is 12 μm. 230 ° C
A clear top coat film 4 was formed by baking for 1 minute. Table 1 shows the type of the base metal sheet 1 of each of the obtained coated steel sheets and a silica compounding example of the clear top coating film 4 formed as the surface layer.

[0032]

[0033]Copy print As a transfer sheet, a sublimable dye (made by Nippon Steel Chemical Co., Ltd.
  Electrostatic plotter type image using sublimation printing toner)
Electrostatic by image printing system (Exis Co. Juana)
It was produced by outputting a pattern on recording paper. Each paint
Overlay the transfer sheet on the clear top coat 4 of the steel plate
Temperature 160 ° C, pressure 0.5 kg / cm ²Transcribe with
Was applied to the clear top coating film 4 by thermocompression bonding for 240 seconds. Pressure
After the deposition was completed, the transfer sheet was peeled off from the base metal plate 1.

Performance Test of Printed Metal Plates Each of the obtained printed metal plates was examined for coating adhesion, coating hardness, workability, abrasion resistance, reflection density, glossiness and transparency of the coating. In the coating film adhesion test, according to JIS G3320, a cross-cutting Erichsen test was conducted in which a cross-cut was put on the coating film surface and pushed out by 6 mm, and the state of peeling of the coating film was investigated by applying / peeling an adhesive tape. If peeling does not occur after peeling the adhesive tape, the rating is 5, the slight peeling is the rating 4, the significant peeling is the rating 3, the peeling close to the entire peeling is the rating 2, the coating film What was peeled off all over was made into the grade 1 and evaluated in five steps. In the film hardness test, JI
The coating film was scratched using Mitsubishi Uni (manufactured by Mitsubishi Pencil Co., Ltd.) according to SK 5400-6-8.4, and the coating film hardness was evaluated by the pencil hardness which is the limit so as not to scratch.

In the workability test, 0 to 6t in a room at 20 degrees
(1t if one plate with the same thickness as the test piece is sandwiched) 1
After applying a bending process of 80 degrees, the coating film surface was observed. 0
⊙ When no crack was detected in the coating film at ~ 2t,
The workability was evaluated by ◯ when the coating film had cracks at 3 to 4 t, Δ when the coating film had cracks at 5 t, and x when the coating film had cracks at 6 t. Generally, if the evaluation score is ◯ or more, it can be put to practical use for a precoated steel sheet. In the abrasion test, a hole having a diameter of 6 mm was made in the center of a test piece having a diameter of 120 mm, the weight of the test piece was measured, and then the test piece was attached to a Taber tester. After rotating the test piece 200 times, the weight was measured. The wear loss was calculated from the weight difference before and after the test, and the Taber index was calculated according to the following formula. Taber index = wear loss (mg) x 1000 / rotation speed (200)

The reflection density is measured by a reflection densitometer (Macbeth Co.
lorChecker SERIES1200) was used to measure the reflection density of cyan. As the glossiness, a specular reflectance measuring device was used to measure the reflectance when the incident angle of light from the light source was set to 60 degrees and the reflection angle was set to 60 degrees. The transparency of the coating film was evaluated by measuring the whiteness (L value) of the cyan printed portion in order to check the degree of white turbidity due to the silica compounding, and using the lightness difference ΔL calculated by the following formula. ΔL = L ₁ −L ₀ L ₁ : L value of each printing-coated metal plate L ₂ : L value of silica-free clear topcoat coating film 4

As can be seen from the results of the survey in Table 2, the printed coated metal sheets of the present invention were all coated with a coating film having an adhesiveness, pencil hardness,
It exhibited satisfactory properties in terms of workability, wear resistance, reflection density, gloss and transparency. Further, as the amount of silica compounded increased, the coating film hardness increased, but on the other hand, abrasion resistance and transparency tended to decrease. On the other hand, the printed coated metal plate of Comparative Example was inferior in any one or more of coating film adhesion, pencil hardness, workability, abrasion resistance, reflection density, glossiness and transparency. That is, in Test Nos. 1 and 5 in which the amount of silica blended was small, the glossiness was too high and flaws were easily noticeable, and the reflection density was insufficient. On the contrary, in Test Nos. 2 and 6 in which the amount of silica blended was large, the transparency was poor and the workability was not sufficient. Further, Test Nos. 3 and 7 in which silica having a small particle size was blended had insufficient coating film hardness, and Test Nos. 4 and 8 in which silica having a large particle size were blended had an opaque coating film and poor wear resistance.

[0038]

[0039]

[Example 2] Clear top coating film through the base coat layer 2
Production of Printed Painted Metal Sheet Forming No. 4 (Invention Examples 13 to 21, Comparative Examples 9 to 12: FIG. 1a) A hot-dip Zn-plated steel sheet having a thickness of 0.5 mm is degreased and surface-conditioned, and a coating-type chromate treatment is performed. After application, the dry film thickness is 15
A white polyester-based resin coating material was applied at a coating amount of μm and baked at a plate temperature of 220 ° C. for 1 minute to form a white base coat layer 2. Then, the dry film thickness is 12
A polyester topcoat paint was applied at a coating amount of μm and baked at a plate temperature of 230 ° C. for 1 minute to form a semitransparent clear topcoat film 4.

In Examples 13 to 21 of the present invention and Comparative Example 9, silica having an average particle size of 2.5 μm was used as a reference for the non-volatile components of the paint.
0% by mass, 0 to 6% by mass of triazine-based ultraviolet absorber (TINUVIN400 manufactured by Ciba-Geigy) and / or benzotriazole-based ultraviolet absorber (TINUVIN384 manufactured by Ciba-Geigy), hindered amine-based light stabilizer (manufactured by Ciba-Geigy)
TINUVIN123) was added as a top-coat paint in a semi-transparent polyester paint containing 1.5% by mass. Comparative Examples 10 to 10
In No. 12, the same polyester type except that the benzophenone type ultraviolet absorber (Viosorb130 manufactured by Kyodo Chemical Co., Ltd.) is used instead of the triazine type ultraviolet absorber and the benzotriazole type ultraviolet absorber in an amount of 1 to 6% by mass based on the nonvolatile component of the paint. A clear top coat film 4 was formed using a paint.

Each UV absorber used was placed in an air atmosphere,
Heat at a heating rate of 5 ° C / min to analyze thermogravimetric analysis, 300 ° C
The weight loss rate was calculated. The weight reduction rate is 3.5% by mass for the triazine-based UV absorber, 5% by mass for the benzotriazole-based UV absorber, and 33% by mass for the benzophenone-based UV absorber. The triazine-based UV absorber and the benzotriazole-based UV absorber The excellent light resistance and heat resistance of the absorbent were confirmed.

Transfer printing The same transfer sheet as in Example 1 was overlaid on the clear topcoat coating film 4 formed on the base metal plate 1, and the temperature was set to 160 ° C.
It was thermocompression bonded under a pressure of 0.5 / cm ² for 240 seconds. After completion of the pressure bonding, the transfer sheet was peeled off from the base metal plate 1.

Performance Test of Printed Metal Plates Test pieces were cut out from each of the manufactured printed metal plates and subjected to a light resistance test. In the light resistance test, in a sunshine carbon arc weather meter set at 63 ° C, 60
The test piece under the condition of spraying with fresh water for 12 minutes during minute irradiation.
It was left for 0 hours. The cyan color tone of the test piece after the test was measured, and the color difference ΔE from the unirradiated test piece was obtained. Also,
In the same manner as in Example 1, the test piece after the test was examined for coating film adhesion and workability. The investigation results are shown in comparison with Table 3 (inventive example) and Table 4 (comparative example).

The print-coated metal sheet according to the present invention exhibited sufficiently satisfactory properties in light resistance, coating adhesion and workability. Among them, in Test Nos. 19 to 21 in which the triazine-based UV absorber and the benzotriazole-based UV absorber were mixed and added at a ratio of 1: 1, the light resistance was higher than that in Test Nos. 13 to 18 in which each was blended alone. It was improving. On the other hand, Test No. 9 in which no ultraviolet absorber was added was inferior in all of light resistance, coating adhesion and workability. Further, in Test Nos. 10 to 12 in which the benzophenone-based ultraviolet absorber was added, sufficient light resistance could not be obtained.

[0045]

[0046]

[0047]

As described above, the printed coated metal plate of the present invention has the silica particles controlling the excessive permeation of the sublimable dye dispersed in the transparent or semi-transparent top coating film to form the base metal or The design property of the undercoat film can be fully utilized, a clear printed pattern is imparted, and the scratch resistance and abrasion resistance are improved. Moreover, since transfer printing using sublimable dyes is adopted, it is possible to produce a large number of small lots in small lots, which enables printing coated metal plates with various patterns to meet various needs. Manufactured. The printed coated metal plate thus obtained is used in a wide range of applications such as full-color advertising billboards, exterior materials, interior materials, exterior materials, outer panels for home appliances, materials for kitchen equipment, etc. To be done.

[Brief description of drawings]

FIG. 1 is a printed coating metal plate (a) having a clear top coating film formed via a base coat layer, a printed coating metal plate (b) having a clear top coating film formed via a base coat layer and a primer layer, and a clear top coating film. The base metal plate (c)
Cross-section of printed metal plate directly formed on the surface

[Explanation of symbols]

1: Base metal plate 2: Base coat layer 3: Primer layer 4: Clear top coat 5: Sublimation dye dyeing layer

Continuation of front page (51) Int.Cl. ⁷ identification code FI C09D 201/00 C09D 201/00 (56) References JP-A-7-31931 (JP, A) JP-A-9-150115 (JP, A) JP-A-8-52420 (JP, A) JP-A-5-255587 (JP, A) JP-A-9-206678 (JP, A) Actually developed 55-23770 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B05D 1/00-7/24 B32B 1/00-35/00 C09D 1/00-10/00 C09D 101/00-201/10

Claims (2)

(57) [Claims] 1. A film thickness of 5 to 4 in which silica having an average particle diameter of 0.5 to 8 μm is dispersed in an amount of 1 to 10% by mass on the basis of non-volatile components of a coating material.
A printed metal plate excellent in scratch resistance, in which a clear topcoat having a thickness of 0 μm and a gloss value of 60 degrees of 10 to 75 is provided on the surface layer, and a sublimation dye penetrates into the topcoat to give a print pattern. . 2. The print-coated metal sheet according to claim 1, wherein the clear topcoat contains a triazine-based UV absorber and / or a benzotriazole-based UV absorber.