JP2003285001A - Thermal transfer coated metal plate excellent in light fastness and adhesion with processed part and printing coated metal plate using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal transfer coated metal plate which is excellent in light fastness hard to generate discoloration and fading even if exposed to the open air over a long period of time and prevented from the generation of ply separation between a base coating film and a topcoating film even if processed severely and excellent in the adhesion with a processed part. <P>SOLUTION: The thermal transfer coated metal plate is constituted by successively laminating a base coating film layer with an elongation of 50-120%, which is formed from a coating material based on a thermosetting polyester resin with a number average molecular weight of 1,000-10,000 and containing 10-50 pts.wt. of an isocyanate curing agent with respect to 100 pts.wt. of the resin solid component, and a clear topcoating film layer with a glass transition temperature (Gf) of 20-60°C, which is formed of a coating material based on the thermosetting polyester resin with the number average molecular weight of 1,000-10,000 and containing 20-150 pts.wt. of a melamine curing agent with respect to the 100 pts.wt. of the resin solid component, on the surface of a metal plate. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

The present invention relates to a full-color advertising billboard,
It is used as a decorative interior material, elevator door material, decorative flooring material, electrical appliances, and outer panels for furniture, etc., and has various printed patterns. The present invention relates to an excellent coated metal plate for heat transfer and a printed coated metal plate using the same.

[0002]

2. Description of the Related Art When a printed coated metal plate is produced using a sublimable dye, the sublimable dye is printed on a clear top coating film layer of the coated metal plate by a printing method such as offset, silk, gravure or transfer. Then, a sublimation dye is permeated into the clear coating film by applying heat treatment. For example, in JP-A-51-24313, a transfer sheet is heated by bringing it into contact with a coating layer of a curable synthetic resin. JP 54
In JP-A-104907, after a sublimation dye is transfer-printed on a coated metal plate to form a printing layer, a top coating film is further formed on the surface layer, and then heat treatment is performed to sublimate the coating film from the inside. The pattern is formed by infiltrating the dye. Further, in Japanese Patent Laid-Open No. 7-31931, a thermal sublimation ink is permeated into the coating film of a prepainted steel plate having a primer coating film and a colored top coating film formed on the steel plate surface. Further, in JP-A-7-102733,
A sublimation colorant is infiltrated into the opaque resin layer provided on the metal plate substrate.

[0003]

All of the conventional printing methods using sublimable dyes attempt to form a pattern by infiltrating the sublimable dye into a clear overcoat. The sublimation dye is usually a disperse dye or an oil dye having a small polarity, and is easily deteriorated by a plasticizer, an organic chemical or the like. In addition, the dye is decomposed by light such as ultraviolet rays, and discoloration or fading easily occurs. Therefore, there is a problem that it is difficult to maintain a stable color and pattern in a usage environment that is exposed outdoors for a long period of time. In addition, printed metal plates impregnated with sublimable dyes may be subjected to processing such as bending depending on the application, but if severely processed, delamination may occur between the base coating and top coating. There was also the problem that there was.

The present invention has been devised in order to solve such a problem, and is resistant to discoloration even when exposed to the outdoors for a long period of time, has excellent light resistance, and is subjected to severe processing even if it is a base. An object of the present invention is to provide a coated metal plate for thermal transfer and a printed coated metal plate which are excellent in adhesion to a processed portion without causing delamination between a coating film and a top coating film.

[0005]

In order to achieve the object, the coated metal plate for thermal transfer excellent in light resistance and adhesion of a processed portion of the present invention has a number average molecular weight of 1,000 to 1,000 on the surface of the metal plate.
The main component is 10000 thermosetting polyester resin,
Formed from a paint in which the ratio of the isocyanate curing agent to 100 parts by weight of the resin solid content is 10 to 50 parts by weight,
A base coating layer having an elongation of 50 to 120% and a thermosetting polyester resin having a number average molecular weight of 1000 to 10000 as a main component, and a proportion of a melamine-based curing agent to 100 parts by weight of a resin solid content is 20 to 150 parts by weight. And a clear top coating film layer having a glass transition temperature (Tg) of 20 to 60 ° C. are sequentially laminated.

Use of an aliphatic or alicyclic diisocyanate such as hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, trimethylhexamethylene diisocyanate, and blocked isocyanates as the isocyanate type curing agent. In addition, the clear topcoat film may contain a triazine-based UV absorber and a benzotriazole-based UV absorber alone or in combination. By printing a transfer paper containing a sublimable dye on such a coated metal plate for heat transfer and heat-treating it, a coating provided with a colored pattern due to the permeation of the sublimable dye is provided on the surface of the metal plate. A coated metal plate is obtained.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors have found that the thermosetting polyester resin coating film constituting the base coating layer has processability and adhesion, and the clear topcoat coating layer has light resistance, processability and scratch resistance. Was examined. As a result, in particular, the elongation percentage of the coating film after film formation can be adjusted by adjusting the average molecular weight of the thermosetting polyester resin constituting the base coating film layer and the blending amount of the isocyanate-based curing agent. It was found that the adhesiveness can be improved and the interlayer adhesion between the base coating film and the top coating film can be improved. Further, the glass transition temperature of the coating film after film formation can be adjusted by adjusting the average molecular weight of the thermosetting polyester resin constituting the clear topcoat coating film layer and the blending amount of the melamine-based curing agent,
It has been found that the workability and the scratch resistance can be improved. Further, they have found that the light resistance of the clear topcoat coating film can be improved by using a melamine type curing agent for the clear topcoat paint. The details will be described below.

The coated metal sheet for thermal transfer according to the present invention, as shown in FIG. 1, is a plated steel sheet, a stainless steel sheet,
A base metal plate 1 such as a cold rolled steel plate or an aluminum plate is formed, and a base coating film layer 2 is formed on the base metal plate 1. Further, a clear top coat film layer 3 is formed as the outermost layer on it. In order to hide the color tone of the base metal plate 1, the color tone of the base coating film layer 2 needs to be colored, and in that case, the base coating film layer 2 preferably has a coating thickness of 10 to 20 μm. . With the base coating film layer 2 having a film thickness of less than 10 μm, the color tone of the base metal plate 1 cannot be sufficiently covered. On the contrary, in the base coating layer 2 having a film thickness of more than 20 μm,
The solvent remaining in the coating film during baking may be rapidly vaporized, and a pinhole-shaped coating film defect called “side” may occur. Further, the thickness of the clear top coat film layer 3 is preferably 6 μm or more. If it is less than 6 μm, the amount of sublimable dye adsorbed is insufficient and a sufficient color tone cannot be obtained. Although the upper limit of the film thickness is not particularly specified, it may be a film thickness that does not cause surface defects such as "armpits" during baking of the clear topcoat paint. Aggregates such as silica may be added to obtain a matte coating appearance.

The base coating layer has a number average molecular weight of 1,000 to
The main component is 10000 thermosetting polyester resin,
It is formed from a paint in which the ratio of the isocyanate curing agent is 10 to 50 parts by weight with respect to 100 parts by weight of the resin solid content. The polyester resin used in the present invention is obtained by polycondensing a dibasic acid and a polyhydric alcohol. Here, the dibasic acid is an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid, or an acid anhydride thereof, for example, phthalic anhydride, orthophthalic acid, isophthalic acid, terephthalic acid, maleic acid, maleic anhydride, fumaric acid. Acids, adipic acid and the like, and these acids are used alone or in admixture of two or more. In order to obtain good light resistance, it is particularly preferable to include phthalic anhydride and / or orthophthalic acid which form a 1,2-benzene-dicarbonyl structure after polycondensation. Adipic acid containing no phenyl group is also used as a suitable dibasic acid.

Polyhydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol,
There are propylene glycol, pentyl glycol, neopentyl glycol, trimethylolethane and the like, which can be used alone or in combination of two or more kinds. In order to obtain good light resistance, it is preferable to use a glycol having a long aliphatic chain such as pentyl glycol.
It is further preferred to use neopentyl glycol which forms a 2,2-dimethyltrimethylene structure.

It is necessary to use a polyester resin having a number average molecular weight of 1,000 to 10,000. If the molecular weight is less than 1000, the base coating film will be insufficiently stretched, cracking of the coating film is likely to occur during processing, and the workability will be reduced. In addition, the base coating film has a too small molecular weight compared to the clear top coating film. And the interlayer adhesion between the topcoat and the top coating film is likely to decrease. On the other hand, when it exceeds 10,000, the molecular weight of the base coating film is too large for the clear top coating film, so that the interlayer adhesion between the base coating film and the top coating film is likely to decrease.

An isocyanate curing agent is used as the curing agent. For example, aromatic diisocyanates such as tolylene diisocyanate and diphenylmethane diisocyanate, and aliphatic or alicyclic diisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, and trimethylhexamethylene diisocyanate, and blocked isocyanates thereof are particularly preferable. Aliphatic or alicyclic diisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, trimethylhexamethylene diisocyanate,
And these blocked isocyanates are preferable from the viewpoint of imparting an appropriate elongation to the coating film. In addition, the compounding amount of the isocyanate curing agent is 100 parts by weight of the resin solid content,
It is preferably 10 to 50 parts by weight. If the amount is less than 10 parts by weight, cross-linking will be insufficient, resulting in poor coating film physical properties such as adhesion and processability. If the amount exceeds 50 parts by weight, the coating film will be too hard and the processability will be deteriorated, and the base coating film and top coat Interlayer adhesion between coatings tends to decrease.

The number average molecular weight of the polyester resin and the kind and amount of the curing agent are adjusted to control the elongation of the coating film to 50 to 120.
Must be set to%. If the elongation percentage is less than 50%, the elongation of the base coating film is insufficient, so that cracking of the coating film is likely to occur during processing and the workability is deteriorated, and the interlayer adhesiveness between the base coating layer and the top coating film layer is reduced. It tends to decrease. On the other hand, when the elongation percentage exceeds 120%, the base coating film is excessively elongated, so that the interlayer adhesion between the base coating film and the top coating film is likely to decrease.

The clear top coat has a number average molecular weight of 10
A thermosetting polyester resin of 00 to 10,000 is used as a main component, and the ratio of the melamine-based curing agent to the resin solid content of 100 parts by weight is 20 to 150 parts by weight. And the glass transition temperature (Tg) of the coating film is 20 to 60
℃. The clear topcoat layer is required to be a resin that dyes well by receiving the sublimable dye that migrates from the transfer sheet, but the polyester resin is well dyed by the sublimable dye, and the resulting image is preserved. The stability is also good. As the polyester resin for forming the overcoat film, a resin obtained by polycondensing a dibasic acid and a polyhydric alcohol is used as in the case of forming the base film.

The number average molecular weight is 1,000 to 10,000 when forming the top coat as well as when it was used for forming the base coat.
Use the polyester resin of. If the molecular weight is less than 1,000, the top coat film does not extend, and the workability decreases. If it exceeds 10,000, the proportion of the cross-linked portion due to melamine decreases, so that it is easily decomposed by ultraviolet rays or the like. Melamine used as a curing agent itself has high light stability, and when mixed with a polyester resin, the light resistance of the resin can be improved. If the melamine content is less than 20 parts by weight, there is no effect of improving the light resistance, and if it exceeds 150 parts by weight, the cross-linking density becomes too high and the coating film tends to crack during processing.

Furthermore, the glass transition temperature (Tg) of the clear top coating film is adjusted to 20 to 60 ° C. by adjusting the number average molecular weight of the polyester resin and the kind and amount of the melamine type curing agent.
Must be set to. Glass transition temperature (Tg) is 20
If the temperature is less than 0 ° C, the hardness of the coating becomes low and the coating becomes easily scratched. Conversely, if the glass transition temperature (Tg) exceeds 60 ° C, the hardness becomes too high and the workability is significantly deteriorated.

When exposed to the outdoors, an ultraviolet absorber is added to the clear top coating film in order to prevent fading of the sublimable dye and deterioration of the gloss of the coating film due to transmission of ultraviolet rays in sunlight. It is preferable. A benzotriazole type or a triazine type is used as the ultraviolet absorber. Preferably, the triazine type is added alone, or the triazine type and the benzotriazole type are added in combination. The ultraviolet absorber is preferably one that reduces the weight by 10% by weight or less at 300 ° C. under a heating condition of a heating rate of 5 ° C./min in the atmosphere.

As the benzotriazole type ultraviolet absorber, octyl-3- [3-t-butyl-5- (2H-benzotriazol-2-yl)]-4-hydroxyphenyl] propinate (TINUVIN 384 manufactured by Ciba-Geigy) is used. ), 2- "2-hydroxy
-3,5-bis (α, α 'dimethylbenzyl) phenyl "-2H-benzotriazole (Ciba Geigy TINUVIN 90
0), methyl-3- [3-t-butyl-5- (2H-benzotriazole
2-yl)]-4-hydroxyphenyl] propinate and polyethylene glycol (molecular weight about 300) condensate (TINUVIN 1130 manufactured by Ciba-Geigy), 2- [2'-hydroxy-3'-
(3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl] -benzotriazole (Viosorb 590 manufactured by Kyodo Chemical Co., Ltd.) and the like.

Examples of triazine-based UV absorbers 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)-
Examples include a mixture of [oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl-1,3,5-triazine (TINUVIN 400 manufactured by Ciba-Geigy).

These ultraviolet absorbers can be used alone or in admixture of two or more. The amount of the UV absorber blended is 3 with respect to 100 parts by weight of the nonvolatile components of the paint.
It is preferable to adjust to about 22 parts by weight. If the blending amount is less than 3 parts by weight, the light resistance of the sublimable dye that has penetrated into the clear top coating film layer tends to be insufficient. On the other hand, if the amount is more than 22 parts by weight, the stain resistance, workability, appearance of the coating film and the like are likely 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 layer, a hindered amine-based light stabilizer may be added to the coating nonvolatile component 100 as needed.
It is preferable to mix 3 parts by weight or less with respect to parts by weight. Examples of the hindered amine-based light stabilizer include the following.

Bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate (SANOL LS770 manufactured by Sankyo Co., Ltd.), bis
(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate (SANOL LS765 manufactured by Sankyo Co., Ltd.), 1- [2- [3- (3,5-di-t
-Butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-t-butyl-4-hydroxyphenyl)
Propionyloxy] -2,2,6,6-tetramethylpiperidine (SANOLLS2626 manufactured by Sankyo Co., Ltd.), 4-benzoyloxy-2,2,6,6-tetramethylpiperidine (manufactured by Sankyo Co., Ltd.)
SANOL 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) (Ciba Geigy TI
NUVIN 144), bis (2,2,6,6-tetramethyl-4-succinate)
Piperidyl) ester (TINUVIN 780 manufactured by Ciba Geigy)
FF), dimethyl succinate and 1- (2-hydroxyethyl) -4-
Polycondensation product of hydroxy-2,2,6,6-tetramethylpiperidine (TINUVIN 622LD manufactured by Ciba-Geigy), 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]] (Ciba Geigy Made CHIMASSORB 944L
D), N, N'-bis (3-aminopropyl) ethylenediamine
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), screws (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-6
7, ADEKA STAB LA-68, ADEKA STAB LA-82, ADEKA STAB LA-87 (manufactured by Asahi Denka Kogyo Co., Ltd.).

These light stabilizers can be used alone or in admixture of two or more. Even if the amount of the light stabilizer added is more than 3.0 parts by weight, the effect of improving the light resistance of the sublimable dye that has penetrated into the coating film is saturated, and no improvement commensurate with the increase in amount is observed. The coating appearance tends to deteriorate. The light stabilizer is preferably added in the range of 0.5 to 2.0 parts by weight.

When a transfer sheet pre-patterned with a sublimable dye is brought into contact with the base metal plate 1 and heated, the sublimated dye permeates into the clear top coat film layer 3 to form a pattern dyed in the thickness direction. It is formed. The transfer sheet is produced by gravure printing, offset printing, screen printing or the like. Further, for small lot printing, an electrophotographic method using a computer graphic which does not require a plate making process, an electrostatic recording method, an ink jet method, a thermal transfer method and the like can be adopted. The sublimable dye is a dye that can be transferred to the clear topcoat coating film layer 3 by a phenomenon such as sublimation or volatilization when heated, and for example, a disperse dye such as a quinophthalone derivative, an anthraquinone derivative or an azo dye is preferably used. . Further, dyes conventionally used for sublimation thermal transfer, sublimation transfer printing and the like can be used without particular limitation.

As this type of yellow dye, Kayase
t Yellow AG, Kayaset Yellow TDN (Nippon Kayaku Co., Ltd.), RTY 52, Dianix Yellow 5R-E, Dianix Yel
lowF3G-E, Dianix Brilliant Yellow 5G-E (above, manufactured by Mitsubishi Chemical Corporation), Blast Yellow 8040, DY108
(Above, Arimoto Chemical Co., Ltd.), Sumikaron Yellow EF
G, Sumikaron Yellow E-4GL (above, Sumitomo Chemical Co., Ltd.), FORON Brilliant Yellow SGGLPI (Sand),
PS Yellow GG (manufactured by Mitsui Toatsu Dyestuff Co., Ltd.) and others.

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 (Mitsubishi Chemical Co., Ltd.) ), Sumikaron Red E-FBL (Sumitomo Chemical Co., Ltd.), Latyl Red B (Du Pont), Sudan Red
7B (manufactured by BASF), Resolin Red FB, Ceres Red 7B (above, manufactured by Bayer).

For the cyan sublimable dye, Kayalon Fast
Blue FG, Kayalon Blue FR, Kayaset Blue 136, Kayas
et Blue 906 (above, Nippon Kayaku Co., Ltd.), Oil Blue
63 (Arimoto Chemical Co., Ltd.), HSB9, RTB31 (above, Mitsubishi Chemical Co., Ltd.), DisperseBlue # 1 (Sumitomo Chemical Co., Ltd.), MS Blue 50 (Mitsui Toatsu Dye Co., Ltd.), Cere
s Blue GN (manufactured by Bayer), Duranol Brilliant Blue 2G
(Made by ICI), etc.

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 (including a case of volatilizing from a liquid state) of 60 ° C. or higher is preferable. When selecting a sublimation dye, a dye having a high sublimation temperature is preferable because it has a relatively large molecular weight and imparts excellent light resistance and heat resistance to the coating film.

When the transfer sheet is heated in contact with the base metal plate 1, the sublimable dye contained in the transfer sheet sublimes, and the clear top coat film layer 3 is formed in the thickness direction as shown in FIG. Penetrate. Therefore, a three-dimensional printed pattern is developed in the clear top coat film layer 3 dyed almost uniformly in the thickness direction. Since the obtained print pattern does not have the sublimable dye concentrated only on the surface layer of the clear top coat film layer 3, print thinning does not occur due to rubbing and the like, and transfer printing after applying a design by thermal transfer The subsequent step of protecting the layer with a transparent resin is also omitted. Moreover, since the printed pattern is developed by the clear top coat film 3 dyed almost uniformly in the thickness direction, a printed pattern excellent in depth feeling, three-dimensional effect, glossiness and sharpness can be obtained. In this way, the required pattern can be easily applied when needed, so that the small-lot production of the designed steel sheet that requires various patterns is facilitated. Moreover, it is not necessary to stock a design steel sheet having a predetermined pattern, and it is possible to perform patterning according to needs. Further, since the dye layer does not exist alone between the clear top coat film layer 3 and the base metal plate 1, delamination unlike the conventional laminated steel plate does not occur.

[0029]

Example 1 Production of Painted Metal Plate Used as Transfer Master Plate A Zn-plated steel plate having a thickness of 0.5 mm was degreased, subjected to surface conditioning treatment and subjected to coating type chromate treatment, and then had a dry film thickness of 15
A white polyester 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 coating film layer. The resin coating for the base coat has a number average molecular weight of 500 to 15,000 (1000 to 10,000 in the present invention, 500 and 1500 in the comparative example).
0) Polyester resin as the main component and resin solid content 10
The isocyanate curing agent content is 0 to 5 parts by weight.
60 parts by weight (10 to 50 parts by weight in the example of the present invention, 5 to 60 parts by weight in the comparative example) was used, and the elongation percentage of the coating film was 30 to 150% (55 in the examples of the present invention).
˜115%, 30-150% in the comparative example). As the isocyanate-based curing agent,
Tolylene diisocyanate (TDI), hexamethylene diisocyanate (HMDI) and isophorone diisocyanate (IPDI) were used.

Then, a clear resin coating is applied to a dry film thickness of 1
It was coated on the white base coating film layer so as to have a thickness of 8 μm. As the clear resin paint, a polyester resin paint containing a polyester resin having a number average molecular weight of 3000 as a main component and a melamine content of 60 parts by weight with respect to 100 parts by weight of a resin solid content was used. In addition, the clear resin paint contains triazine-based UV absorber (TINUVIN manufactured by Ciba Geigy).
400) and a benzotriazole-based ultraviolet absorber (TINUVIN 384 manufactured by Ciba-Geigy) were mixed at a ratio of 1: 1 and 8 parts by weight based on the non-volatile components of the paint were added. Furthermore, a hindered amine light stabilizer (TINUVIN 123 manufactured by Ciba-Geigy) was added to all clear resin paints in an amount of 1.5 parts by weight based on the non-volatile components of the paint. The applied coating material was baked at a plate temperature of 230 ° C. for 1 minute to form a clear top coating film layer having a Tg of 35 ° C. Table 1 shows the composition and film thickness of the base coating film of each obtained coated steel sheet.

[0031]

Transfer printing An ink jet printer (JV2-13 manufactured by Mimaki Engineering Co., Ltd.) is used with a sublimation dye ink (manufactured by Kiwa Chemical Industry Co., Ltd.) prepared from a cyan sublimation dye.
In 0), a solid cyan pattern was output on the output paper. The obtained transfer paper is overlaid on the coated surface of the coated steel sheet, and the temperature is set to 16
It was thermocompression bonded at 0 ° C. and a pressure of 0.5 kg / cm ² for 150 seconds. After completion of the pressure bonding, the electrostatic recording paper was peeled off from the coated steel sheet.

Performance Test of Print Coated Steel Sheets Light resistance, coating film adhesion, workability, processed part adhesion and flaw resistance were investigated for each of the print coated steel plates manufactured as described above. The survey results are shown in Table 2. The properties shown in Table 2 were evaluated as follows. For the light resistance test, a sunshine carbon arc weather meter set to a temperature of 63 ° C with a black panel (spraying with fresh water for 12 minutes during irradiation for 60 minutes)
The color difference ΔE between the test piece after 240 hours and the unirradiated test piece was measured. Then, after 240 hours, ΔE of less than 6 was evaluated as ◯, 6 or more and less than 10 was evaluated as Δ, and 10 or more was evaluated as x. In addition, if it is Δ or more, it can be put to practical use.

The coating film adhesion test is conducted in a cross-cutting Erichsen (J
6m with a grid pattern specified in IS G3320
m Extrusion) test was performed, and the presence or absence of peeling of the coating film due to the peeling of the pressure-sensitive adhesive tape was observed. As for workability, we performed a 5t 180-degree bending process (1t when one plate with the same thickness as the test piece was sandwiched) in a room at 20 ° C, and investigated the occurrence of cracks in the coating film according to the degree of bending. It was evaluated by doing. 5t
When the coating film had no cracks, it was evaluated as ◯, and when the coating film had cracks at 5t, it was evaluated as x. In addition, when it is ◯, it can be put to practical use for a precoated steel sheet.

The adhesion of the processed part is 1 to 2t in a room at 20 ° C.
After applying an 80 degree bending process and pressing the adhesive tape on the bent part, observe the presence or absence of peeling of the coating film due to peeling of the adhesive tape, ○ if there is no peeling, ○ It was set to x. As for the scratch resistance test, JIS K540
According to 06-8.4, a pencil method (manufactured by Mitsubishi Uni Mitsubishi Pencil Co., Ltd.) was used to investigate the flaw method, and the pencil hardness was evaluated as the maximum pencil hardness without flaws. In addition, if it is F or more, it can be put to practical use.

As is clear from Table 2, in the examples of the present invention, the light resistance, the coating film adhesion, the workability, the processed part adhesion, and the scratch resistance were all sufficiently satisfactory. On the other hand, in the comparative example, one or more of the coating film adhesion, workability, and processed portion adhesion were inferior. That is, Comparative Example Sample No. 6, which has a low coating film elongation rate due to the small number average molecular weight of the polyester resin, is inferior in workability and processed portion adhesion, and conversely has a large number average molecular weight, resulting in a coating film elongation rate. Comparative Example Sample No. 7, which was too high, was inferior in the processed part adhesion. In addition, Comparative Example Sample Nos. 8 and 9 in which the coating film elongation rate was low due to an unsuitable compounding amount of the isocyanate curing agent were inferior in workability and work part adhesion.

[0037]

Example 2 Next, various clear top-coat paints were used as a white base in order to see the effects of the number average molecular weight of the polyester resin forming the clear top-coat paint film, the blending amount of the melamine curing agent and the Tg of the paint film. It was applied on the coating layer. As the white base coating layer, the one of Sample No. 2 in Example 1 was used. In addition, for some samples, a triazine-based UV absorber (Ciba Geigy TI
NUVIN 400) and a benzotriazole type ultraviolet absorber (TINUVIN 384 manufactured by Ciba-Geigy) were mixed at a ratio of 1: 1 and 8 parts by weight based on the non-volatile component of the coating material was added. Further, to all the clear resin paints, a hindered amine light stabilizer (TINUVIN 123 manufactured by Ciba Geigy) was added in an amount of 1.5 parts by weight based on the non-volatile components of the paint. Example 1
Similarly to the above, the applied coating material was baked at a plate temperature of 230 ° C. for 1 minute to form a clear top coating film. Composition of clear top coating film and coating film T of each obtained coated steel sheet
g is shown in Table 3.

[0039]

For each of the obtained coated steel sheets, the same performance test as in Example 1 was conducted. The results are shown in Table 4.

[0041]

As is clear from Table 4, in the examples of the present invention, the light resistance, the coating film adhesion, the workability, the processed part adhesion, and the scratch resistance were all sufficiently satisfactory. On the other hand, in the comparative example, one or more of light resistance, coating film adhesion, workability, processed part adhesion, and scratch resistance were inferior. That is, Comparative Example Sample No. 17 in which the polyester resin has a small number average molecular weight and a high Tg.
Is poor in processability, and conversely, Comparative Example Sample No. 18, which has a high number average molecular weight and a low Tg, was inferior in light resistance and scratch resistance. Further, Comparative Example Sample No. 19 containing a small amount of the melamine-based curing agent was inferior in light resistance, and conversely, Comparative Example Sample No. 20 containing a large amount of the melamine-based curing agent was inferior in workability.

[0043]

As described above, the coated metal sheet for heat transfer of the present invention is formed from a coating material containing a thermosetting polyester resin having a specified number average molecular weight as a main component and an isocyanate curing agent in an adjusted proportion. It is formed from a base coating film layer whose elongation rate is set within a predetermined range and a thermosetting polyester resin whose number average molecular weight is specified as the main component and whose proportion of melamine-based curing agent is adjusted. By sequentially laminating the clear top coating film layers in which (Tg) is set within a predetermined range, excellent light resistance and processed portion adhesion are exhibited. Therefore, the printed coated metal plate obtained by applying this coated metal plate to the thermal transfer method has excellent design and is used in a wide range of fields such as full-color advertising signs, decorative interior materials, electric appliances, and outer plates of furniture.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a cross-section of a surface layer portion of a printed and coated metal plate according to the present invention.

[Explanation of symbols]

1: Base metal plate 2: Base coating layer 3: Clear topcoat coating layer 4: Sublimable dye dyeing layer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masaki Sato             7-1 Takaya Shinmachi, Ichikawa City, Chiba Prefecture Nisshin Steel             Technical Research Institute Co., Ltd. (72) Inventor Kenji Koshiishi             7-1 Takaya Shinmachi, Ichikawa City, Chiba Prefecture Nisshin Steel             Technical Research Institute Co., Ltd. F-term (reference) 4D075 AC43 AE03 CA03 CA13 CA32                       CB06 CB11 DA03 DA06 DB01                       DB02 DB04 DB05 DB07 DC02                       DC10 DC38 EA07 EA43 EB32                       EB35 EB38 EB52 EB53 EB56                       EC07 EC17                 4F100 AB01A AB18 AH03B AH03C                       AK44A AK44C AK51B AL05B                       AL05C BA03 BA04 BA07                       BA10A BA10C BA10D CA02                       CC03B CC03C DG10D EC04D                       EH46 EH462 EH71 EH711                       EJ42 EJ422 EJ69 EJ691                       GB08 GB48 GB90 JA05C                       JA07A JA07C JK08B JL09                       JL11 JM02B JM02C JN01C                       YY00A YY00B YY00C

Claims (4)

[Claims] 1. A number average molecular weight of from 1,000 to 1000 on the surface of a metal plate.
The main component is 10000 thermosetting polyester resin,
Formed from a paint in which the ratio of the isocyanate curing agent to 100 parts by weight of the resin solid content is 10 to 50 parts by weight,
A base coating layer having an elongation of 50 to 120% and a thermosetting polyester resin having a number average molecular weight of 1000 to 10000 as a main component, and a proportion of a melamine-based curing agent to 100 parts by weight of a resin solid content is 20 to 150 parts by weight. Which has a glass transition temperature (Tg) of 20 to 60 ° C. and is sequentially laminated with a clear top coating film layer, which is excellent in light resistance and adhesion to a processed portion. Board. 2. The isocyanate-based curing agent is selected from aliphatic or alicyclic diisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate and trimethylhexamethylene diisocyanate, and blocked isocyanates thereof. A coated metal plate for thermal transfer, which is excellent in light resistance and adhesion to a processed portion according to claim 1. 3. The clear topcoat film, which contains a triazine-based UV absorber and a benzotriazole-based UV absorber alone or in combination, is excellent in light resistance and adhesion to processed parts. Painted metal plate for heat transfer. 4. A colored pattern is imparted by permeation of a sublimable dye by superimposing a transfer paper containing a sublimable dye on the coated metal plate for thermal transfer according to any one of claims 1 to 3 and performing heat treatment. A printed coated metal plate, wherein the coated film is provided on the surface of the metal plate.