JPH0249913B2 - PURASUCHITSUKUSEIKEITAIHENOGAZOKEISEIHO - Google Patents

Description

[Detailed description of the invention]

<Technical Field of the Invention> The present invention is directed to a heat transferable dye, a dihydric alcohol, a trihydric alcohol, a monohydric alcohol with a boiling point of 200°C or higher under normal pressure, or a mixture thereof, and an infrared absorber. The ink is fixed using a flash of xenon strobe, and is colored with a heat-transferable dye.
This invention relates to an image forming method that makes it possible to instantaneously form a penetrating image on the surface of certain kinds of plastics that are difficult to dye, without changing their shape. <Prior art and its problems> Conventionally, for coloring and dyeing plastic molded objects, such as films, sheets, and molded products, methods of fixing by adhering ink to the printing material, or dissolving or dispersing dyes in the plastic itself have been used. There are methods to uniformly color the material at the same time as the molding process. However, in the former case, various durability is poor due to fixing by adhesion, and a coating layer may be required for further protection after fixing. In the latter case, the dye is dissolved or dispersed in the plastic before molding, which not only makes it difficult to obtain multiple colors, but also causes a large amount of dye loss. <Summary of the Invention> The present invention was made in order to improve the above-mentioned problems.The plastic surface on which an image is to be displayed is coated with mainly a heat-transferable dye and a dihydric alcohol, a trihydric alcohol, or a material with a boiling point under normal pressure.
An ink image is formed directly or using a transfer sheet with an ink made of monohydric alcohol at 200°C or less, or a mixture thereof, and an infrared absorber, and then colored with a heat-transferable dye by irradiation with a flash of xenon strobe. This is an image forming method that makes it possible to instantly form a penetrating image on certain types of plastics that are difficult to dye, without changing their shape. <Detailed Description of the Invention> To explain the present invention in more detail, the ink used here mainly contains a heat-transferable dye and a dihydric alcohol, or a trihydric alcohol, or a monohydric alcohol with a boiling point of 200°C or less under normal pressure.
Alternatively, it is made of a mixture of these and an infrared absorber, and is non-drying or extremely slow-drying at room temperature, and by heating with flash irradiation from a xenon strobe, a penetrating image can be created inside the plastic material to be printed. It is characterized by causing it to form. The heat-transferable dye used here is preferably a disperse dye or oil-soluble dye from the viewpoint of rapid processing such as fixing, and due to the unique composition of the ink, it is more tolerant than conventional inks in terms of dispersion stability. Therefore, the dye can be used without special dispersion stabilization treatment. The dye should be selected appropriately taking into account the type of solvent, fixing ability during fixing, etc. Specifically, the product names include Sumikalon Violet 3BL, Yellow E-FG, Orange E- G.
Violet RL, Blue E-FBL (manufactured by Sumitomo Chemical Co., Ltd.), Diaceritone First, Violet B, Dianex Yellow 5R-E,
Red RE, Brilliant Red BS-E, Navy Blue ER-FS (manufactured by Mitsubishi Kasei Corporation), Oransen Red 2G, Oransen Red B, Oransen Blue B, Oransen Scarlet 2G, Oranzol Yellow 3G (and more) Ciba Corporation), Miketon First Scarlet B, Miketon Polyester Red FB (manufactured by Mitsui Toatsu Co., Ltd.), Kayaset Blue FR (manufactured by Nippon Kayaku Co., Ltd.), Mihara Oil Yellow 5G, Mihara General dispersions such as Oil Orange G, Mihara Oil Orange R, Mihara Oil Red 5B, Mihara Oil Green AX (manufactured by Mihara Kako Co., Ltd.), Oil Yellow G, Oil Black FBB (manufactured by Toyo Ink Manufacturing Co., Ltd.), etc. Various dyes and oil-soluble dyes can be used. The medium for such heat-transferable dyes is dihydric alcohol, trihydric alcohol, monohydric alcohol with a boiling point of 200°C or higher under normal pressure, or a mixture thereof, which does not dry at room temperature and dries extremely slowly, making it difficult to ink. It has been found that the solvent can be sufficiently evaporated at a heating temperature that causes the heat-transferable dye to migrate into the interior of the substrate without changing the fluidity of the dye. Among the solvents used in general stamp inks, high-boiling petroleum solvents, and other solvents, it has not been possible to find a solvent that satisfies both stability at room temperature and quick drying properties when heated. Since the dye may decompose at a temperature of about 300°C, it is necessary to be able to evaporate the solvent at a temperature lower than that and within a short time. For example, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, butylene glycol 1,4, butylene glycol 2,3, hexylene glycol, octylene glycol, polyethylene glycol, glycerin,
Such as benzyl alcohol. The above-mentioned dye and solvent are arbitrarily selected depending on the purpose of use, and the ink is made by kneading in a usual manner. However, in consideration of the special image forming object described below, an infrared absorbing agent is added to the ink. It is necessary to add a small amount of The following formulas () and () are used as infrared absorbers.
Specific examples include those having the following. In the formula, A represents a quaternary ammonium group, and in the formula (), A is a tetrabutylammonium salt, bis(1-thio-2-phenolate)nickel-
For tetrabutylammonium, the following formula ()
When A is bis(1-thio-2-naphtholate)nickel-tetrabutylammonium, which is a tetrabutylammonium salt, it is represented by the following formula (). Here, bis(1-thio-2
Nickel-tetrabutylammonium (naphthlate) has absorption maximums at wavelengths of 730 nm, 1110 nm, and 1370 nm, and has the property of absorbing near-infrared rays over a wide wavelength range of 1000 to 1600 nm. In addition to the fixing effect of the ink due to the addition of these infrared absorbers, the amount of addition is due to changes in the hue of the ink,
Considering economical efficiency, it is preferable to add the dye in an amount of 1 to 20% by weight based on the amount of dye in the ink. Other infrared absorbers include N, N, N',
N'-tetrakis(P-substituted phenyl)-P-phenylenediamines, benzidines, and their aluminum salts and diimonium salts, with the general formula () Compounds represented by the following are preferred. In the formula, R is hydrogen or a lower alkyl group, X is an anion selected from the group consisting of hexafluoroarsenate ion, hexafluoroantimonate ion, fluoroborate ion, and perchlorate ion, and m is 0
or an integer between 1 and 2, A is

[Formula] Ma Taha

[Formula] is shown, n is an integer of 1 or 2, and when m is 2, A is

[Formula] is shown. Among them, N-tetraphenyl-benzoquinone-
Diimonium salts, particularly those having the following general formula, are preferred. In this general formula, XX'YY' each represents an alkyl group containing up to 6 carbon atoms, RR' each represents a substituted or unsubstituted phenyl group, and A represents an anion, if any. Examples include chloride, nitrate, chlorate, sulfate, sulfonate, hexafluoroarsenate, hexafluoroantimonate, and the like. Fluorenol salts also absorb infrared radiation, and the general formula is given as follows. In this general formula, R ₁ R ₂ R ₃ each represents a hydrogen atom, O—C _o H _2o+1 (n is between 1 and 6), or an amino group. At least two of these are amino groups, X represents an anion if there is any, and one or more hydrogen atoms can be substituted with the following substituents. In other words, alkoxy, alkyl, chlorine, bromine,
Examples include fluorine, nitro, acyl, acylamide, and sulfonamide. Others include first iron or second iron.
Chelates of O-quinone monooximes of iron, such as ferrous 1,2-naphtho-quinone oximate, ferrous 6-bromo-1,2-naphtho-quinone oximate, and 3,5-hydroxy Alternatively, 3,5-7'-hydroxy-naphtho-quinone ferrous oximate, ferrous oximate in which 0.5 to 2 mol of dinitrosoresorcin is mixed per 1 mol of 1-nitroso-2-naphthol, etc. be. As is clear from the purpose of the present invention, infrared absorbers are not limited to those described above. Infrared absorbers such as carbon black and iron oxide can also be used. Furthermore, it is also effective to use a mixture of these infrared absorbers. On the other hand, plastic molded articles that can be used in the present invention include polycarbonate, polyphenylene sulfide, polyether sulfone, which has a high glass transition temperature, tetrafluoroethylene-hexafluoropropylene copolymer resin, which has a high crystal density, It is a plastic molded product made of fluorinated chloroethylene resin, vinylidene fluoride-hexafluorinated propylene copolymer resin, and thermosetting resins such as phenol resin and epoxy resin. Although it is not easy to color or dye these plastics with heat-transferable dyes, it is possible to create a good penetrating image on their surface by using an ink with the above composition and using the image forming method described below. It becomes possible to form. Next, as a method of printing on the above-mentioned plastic molded body which is a printing medium, there are a method of directly printing an ink image on the printing medium and a method of transferring an ink image. Direct printing methods include letterpress printing, dry offset printing, flexo printing, intaglio offset printing, gravure offset printing, and silk screen printing. In these methods, the blanket used for dry offset printing, intaglio offset printing, and gravure offset printing should have as low a hardness as possible so that ink transferability is good and clear printed images can be obtained. Regarding the transfer method, there are two methods: printing an image on a transfer sheet in advance and transferring the ink image to the printing material under pressure at a low temperature, and applying (impregnating) the ink on the entire surface of the transfer sheet to create the desired image. There is a method in which a mold having an image is transferred to a printing material under low temperature pressure. The transfer sheet used for ink image formation here includes films such as polyester, cellophane, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, polycarbonate, acetate, coated paper, etc., and laminates thereof, or Examples include metal sheets such as steel and aluminum. In addition to the above-mentioned transfer sheet, cloth, paper, etc. may be used as the transfer sheet used for the entire surface coating (impregnation). Here, the transfer conditions are room temperature to 60℃, pressure 5 to 20Kg/
cm ³ and time is 0.5 to 2 seconds. In the present invention, as a method of fixing the ink to the plastic molded article, a method of instantaneously heating the article by flash irradiation from a xenon strobe is used. <Effects of the Invention> Since the present invention has the above configuration, it has various effects shown below. That is, the present invention uses an ink whose main components are a heat-transferable dye, a dihydric alcohol, a trihydric alcohol, a monohydric alcohol with a boiling point of 200°C or more under normal pressure, or a mixture thereof, and an infrared absorber. Furthermore, since a flash of xenon light strobe is used to fix the ink image, a good penetration image is instantaneously formed on the surface of the plastic molding, which is difficult to be colored or dyed with heat-transferable dyes. Furthermore, since image formation is instantaneous, deformation of the plastic molded body due to heating during fixing can be prevented. Furthermore, the plastic molded article having a penetration image obtained by the present invention has a wide range of applications, such as various cards, sheets, decorative boards, keyboards,
Possible applications include eyeglass frames and nameplates. In addition, since the pigment is instantly permeated into the plastic, the image has excellent resistance such as abrasion resistance, dimensional stability, and chemical resistance, and can satisfy the suitability required for each application. . <Examples> Examples of the present invention will be described below. <Example 1> Oil black FBB (manufactured by Toyo Ink Manufacturing Co., Ltd.) 30
parts, 10 parts of ethylene glycol, 10 parts of triethylene glycol, 20 parts of tetraethylene glycol, and as an infrared absorber, bis(1-thio-2-naphthorate)nickel-tetrabutylammonium.
The ink obtained by mixing 1.5 parts (5% by weight based on the amount of dye) and kneading is impregnated into a nonwoven fabric, and the ink is applied onto a polycarbonate plate at room temperature and under a pressure of 5 kg/cm ² using a metal mold with an image. After transferring, use a xenon light strobe (Commet Strobe CH-2000XT)
When irradiated with a light intensity of 10W・sec/cm ² ,
A clear penetration image could be obtained instantly without deforming the printing material. <Example 2> Diamond thread R-E (Mitsubishi Chemical Industries, Ltd.)
), 15 parts of polyethylene glycol #200, and 1.5 parts of bis(1-thio-2-phenolate) nickel-tetrabutylammonium (5% by weight based on the amount of dye) as an infrared absorber were mixed and ground. Using the obtained ink, an ink image was formed on a tetrafluoroethylene-hexafluoropropylene copolymer resin plate using a silk screen printing method.
2000XT) at a light intensity of 10 W sec/cm ² , it was possible to instantly obtain a clear penetration image without deforming the printing material. <Example 3> Chemiton Polyester Red FB (Mitsui Toatsu Co., Ltd.)
60 parts of polyethylene glycol #200 and 9 parts of bis(1-thio-2-naphthorate)nickel tetrabutylammonium as an infrared absorber.
(15% by weight based on the dye amount) and knead the resulting ink. After forming an ink image on a Bakelite (phenol formaldehyde) resin plate using the dry offset printing method, a xenon light strobe ( Comet strobe CH-2000XT)
When irradiated with a light intensity of 10W・sec/cm ² ,
A clear penetration image could be obtained instantly without deforming the printing material.

Claims (1)

[Claims] 1. A heat-transferable dye and a dihydric alcohol, a trihydric alcohol, or a material having a boiling point under normal pressure.
Polycarbonate with a high glass transition temperature,
Polyphenylene sulfide, polyether sulfone, tetrafluoroethylene-hexafluoropropylene copolymer resin with high crystal density, trifluorochloride ethylene resin, fluorocarbonylidene-hexafluoropropylene copolymer resin, and heat An ink image is formed on a plastic molded body made of curable resins such as phenol resin and epoxy resin, and then the surface of the molded body is irradiated with a flash of light from a xenon strobe to instantly create a penetrating image on the surface of the molded body. 1. A method for forming an image on a plastic molded body, characterized by forming an image on a plastic molded body. 2. The method according to claim 2, wherein the infrared absorber is a compound represented by the following general formula. (In the formula, A represents a quaternary ammonium group.) 3. The method according to claim 2, wherein the infrared absorber is a compound represented by the following general formula. (In the formula, A represents a quaternary ammonium group.) 4. The method according to any one of claims 1 to 4, wherein an ink image is formed by a transfer method.