JPS6335387A - Thermal transfer recording method - Google Patents

Abstract

PURPOSE:To prevent a sublimable dye from being scattered and lost and contrive a higher printing speed, by placing an image-receiving paper in close contact with a protective layer provided with minute holes, and applying heat thereto to thermally transfer image information. CONSTITUTION:A thermal transfer recording film comprises an ink layer 2 comprising a sublimable dye and a protective layer 3 comprising a thermoplastic resin and having a thickness of 0.1-3mum on a base layer 1. When the protective layer 3 is irradiated with laser light 5 according to image information, a minute hole 7 having a diameter of 0.1-100mum is formed at each irradiated part 4 of the layer 3. When an image-receiving paper 8 is laid on the recording film thus perforated, and heat is applied thereto from the side of the base layer 1 by a thermal head 10, the sublimable dye at only the parts of the ink layer 2 corresponding to the minute holes 7 is sublimed, and is transferred to the paper 8 to form dots 9, whereby recording is achieved.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a thermal transfer recording method.

[Conventional technology]

In recent years, thermal transfer recording is non-impact and noiseless.

Due to its characteristics of being maintenance-free, low-cost, compact and lightweight, and capable of color printing, it has come to be used in many fields such as printers, recorders, computer terminals, and facsimile machines. In particular, thermal transfer recording methods using sublimable dyes require density gradations, and therefore are suitable for use in video printers and the like, as they allow full color recording with intermediate gradations.

[Problem that the invention seeks to solve]

Several drawbacks appear when using sublimable dyes as colorants. This is because the colorant is sublimable and easily dissipates.

°Thermal transfer recording film is often wound into a roll as a general product, but during long-term storage, the sublimable dye spreads through the ink layer to the surface of the ink layer and sublimates. be. Since the end surface of the roll is prone to sublimation and dissipation, when thermal transfer printing is performed, the image density of the portion corresponding to the end surface of the roll is reduced.

[Means for solving problems]

The present invention provides a method for thermal transfer recording that prevents dissipation of sublimable dyes.

That is, in the recording film used in the method of the present invention, a protective layer made of a thermoplastic resin that can maintain a solid state at room temperature to 70° C. is provided on the outer surface of an ink layer containing a sublimable dye.

However, providing a thermoplastic protective layer is effective in preventing the dissipation of the sublimable dye, or because it has a protective layer, heat can be applied using a normal method (such as a thermal head) to thermally transfer the dye to the image receiving paper. It is not possible.

In order to solve this drawback, the present invention irradiates the protective layer from the protective layer side with a high-energy-density laser source corresponding to image information to make micro-holes, and thermally transfers the sublimable dye to the image-receiving paper through the micro-holes. It is to be recorded.

Based on this idea, as a result of intensive studies, we have arrived at the present invention. That is, in the present invention, an ink layer containing a sublimable dye is provided on the support layer, and a protective layer consisting of a thermoplastic resin as a main component (with a thickness of 11 to 3 μm) is provided adjacent to the core layer. , in a thermal transfer recording film consisting of at least a support layer, an ink layer, and a protective layer, a laser source having image information is irradiated from the protective layer side to the protective layer to completely melt the thermoplastic resin of the protective layer and form a diameter α1. Thermal transfer recording, characterized in that image information is thermally transferred by punching micropores of ~100 μm, then placing an image receiving paper in close contact with the protective layer, and applying heat from the support layer side with a heat application head. Method,
It is.

[Effect]

FIG. 1 shows a thermal transfer recording film lapos used in the method of the present invention. The support layer 1 is made of polyethylene terephthalate (p
x'r)e Nylon 6, nylon 66, polycarbonate, polysulfone, polyether sulfone, mediphenylene sulfide. Films such as polyetheretherketone are suitable, particularly PET biaxially stretched films.

The sublimable dye as a coloring agent contained in the ink layer 2 is
A dye that vaporizes from a solid state at a temperature of 100 to 400°C is preferable, and has a chemical structure such as an azo-based, anthraquinone-based, styryl-based, quinophthalone-based, or nitrodiphenylamine-based dye.

Specifically, for example, Kayalon First Yellow, Kayalon First Orange, Kayalon First Blue, and Kayalon First Green.

Kayalon First Blue Green, Kayalon First Red, Kayalon First Violette (manufactured by Nippon Kayaku Co., Ltd.), Dia X Fast Yellow, Diaceriton First Scarlet, Dia Seven Lidone First Orange.

Seriton First Yellow (Mitsubishi Kasei Corporation Ill)
, Miketon Discharge Yellow, and Miketon First Violet (Mitsui Toatsu Chemical Co., Ltd.).

As the binder for retaining the sublimable dye in the ink layer 2, cellulose thread resins such as nitrocellulose, methylcellulose, ethylcellulose, carboxymethylcellulose, cellulose acetate, polyester resins, or polyvinyl alcohol are suitable.

The protective layer 3 is made of a thermoplastic resin that thermally melts at 70 to 200°C and causes flow. Polyolefins such as polystyrene, polyethylene, polypropylene, butyral,
Vinyl chloride, vinyl acetate.

PVC/vinyl acetate copolymer, ethylene/vinyl acetate copolymer.

There are PIT modified products, polyamide modified products, etc.

FIG. 2 shows an embodiment in which the recording film used in the method of the present invention is irradiated with a laser source to perforate micropores in the protective layer. High-density laser focused by optical lens 5
is applied to the protective layer 3 in accordance with the image information. Heat accumulates in the portion 4 most irradiated with the laser, and the heated portion 4 of the protective layer melts. The melted part 4 becomes flowable, but the temperature of the peripheral part is lower than that of the central part.
Since there is a temperature gradient from the center to the periphery, the surface tension of the molten resin is smaller in the center than in the periphery, which also creates a surface tension gradient. Due to this gradient, the molten resin is subjected to tensile tension at the periphery, and micropores are perforated. As shown in FIG. 2(b) 6.7, the shape of the small hole a is slightly raised at the periphery 7.

Ar ions are used as a laser light source.

Kr+ ion, Ne-He, He-Cd, YAG
, GaAs, and Cog lasers. The smaller the laser output, the more desirable it is, but l:L25 to 1W is used. From the point of view of image quality, it is desirable to increase the resolution, but the size of the micropores is a diameter [lL1~1COμm1, preferably 1~25μ vortex.

In order to drill microholes of the above size with the above laser output, the thickness of the protective film should be α05~3μ, preferably 1
The groove is 5 to 1.0μ.

FIG. 6 shows an embodiment in which a sublimable dye is sublimated and transferred to the image receiving paper 8 stacked on the recording film at the perforated microporous positions using a thermal head 10 in which a heating resistor is embedded as a heat imparting head. show.

When heat is applied from the support layer 1 side using a thermal head, only the sublimable dye in the portion of the ink layer 20 corresponding to the portion of the micropores 7 of the protective layer 3 perforated in accordance with the image information is sublimated, and the image receiving paper 8 to form dots 9 and are recorded.

Further, as shown in FIG. 4, thermal transfer recording can also be performed by an energizing thermal transfer method using an energizing recording electrode head 12 instead of a thermal head as the heat applying head. In this case, support layer 1. In addition to the ink layer 2 and the protective layer 3, an electrically conductive thermal transfer recording film is used in which a resistance layer 11 is provided on a support layer. A current 14 flows from the recording electrode 12 to the return electrode 13.
Flowing through the resistance layer 11, ohmic heat is generated in the resistance layer, and this heat is used to perform electrical thermal transfer recording.

〔Example〕

Example 1 As a support layer, an ink layer having the following ink composition was solution coated on a PET Z axially stretched film (6 μm, manufactured by Toshiku Co., Ltd.) using a wire bar (thickness after drying: 4.5 μm).
).

Solution composition of ink layer; Sublimable dye; Kayalon Fast Red R112wt%
(manufactured by Nippon Kayaku Co., Ltd.) Fractional agent; Demol N, swt% (Kao Soap Co., Ltd.)
Binder: Methyl cellulose * 12 wt% water nia 1 wt% Next, a solution of a protective layer resin having the following composition was prepared, solution coating was performed using a wire bar, and after drying, a protective layer with a thickness of 1.0 μm was formed. .

Resin solution composition of protective layer: Resin: Butyral, 25 wt% (manufactured by Tanezu Kagaku Co., Ltd.) Solvent: Methyl ethyl ketone, 75 wt% or more The thermal transfer recording film of the present invention was prepared by the method.

Example Z The protective layer side of the recording film obtained in Example 1 was focused with an Ar laser beam (wavelength: 515 m) using a lens to create a beam with a diameter of about 25 μm, and was irradiated with a laser output of 500 mW. At this point, approximately circular micropores with a diameter of about 15 μm were formed.

Example 5 An image receiving paper was placed on the protective layer of the recording film having micropores obtained in Example 2. Thermal head (
Resistor 220Ω, working voltage 25V, pulse width 1.55s
Heat was applied by ec). Immediately after, the recording film and image receiving paper were peeled off, and a dot with a diameter of about 10 μm was printed.

〔Effect of the invention〕

In the method of the present invention, dissipation of the sublimable dye can be prevented by providing a protective layer on the thermal transfer recording film.

Furthermore, since image information is written using laser light, printing and printing speeds can be increased.

The present invention provides a new type of printer with laser Qyi & inscription and thermal transfer with a conventional thermal head or energized electrode head.

[Brief explanation of drawings]

FIG. 1 shows a thermal transfer recording film of the present invention, in which 1; support layer; 2; ink layer; 3;
α) is a diagram in which the protective layer is irradiated with laser light 5, Figure 2 Cb) is a diagram in which one fliH hole 7 is perforated in the protective layer by laser light, and Figure 3 is a record in which the protective layer is perforated. FIG. 4 is a diagram showing an embodiment in which ink 9 is transferred to image receiving paper 8 by heat application by a thermal head 10 having a heating resistor embedded in the support layer side of the film. A current-carrying recording electrode 1 is provided on a recording sheet having a magnetic resistance layer 11.
2 is a diagram showing an embodiment in which ink 9 is transferred onto image receiving paper 8 by means of poles 15 on the return path. /-1 Figure 1 Figure 2

Claims (1)

[Claims] An ink layer containing a sublimable dye is provided on the support layer, and adjacent to the ink layer, an ink layer containing a thermoplastic resin as a main component,
．． In a thermal transfer recording film comprising at least a support layer, an ink layer, and a protective layer provided with a protective layer having a thickness of 1 to 3 μm, the protective layer is protected by irradiating the protective layer with a laser beam having image information from the protective layer side. By melting the thermoplastic resin of the layer and perforating micropores with a diameter of 0.1 to 100 μm, then placing an image receiving paper in close contact with the protective layer and applying heat from the support layer side using a heat application head. , a thermal transfer recording method characterized by thermally transferring image information.