JPH06206325A - Thermal color printer - Google Patents

Abstract

PURPOSE:To prevent an irregular fixing from being caused by dust and foreign particles and prevent a thermal head from being thermally affected. CONSTITUTION:Aluminum plates 28, 29 are provided on a base frame 19 so as to be opposed to fixing lamps 25, 26, respectively. On the center parts of the aluminum plates 28, 29, anodized aluminum layers are provided long and narrow. Through these layers, UV rays are emitted to a thermal color recording material 10 from the fixing lamps 25, 26.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color thermal printer using a color thermal recording material which develops color by heat energy.

[0002]

As a color thermosensitive recording material, for example, as described in JP-A-61-213169, a magenta thermosensitive coloring layer, a cyan thermosensitive coloring layer, and a yellow thermosensitive coloring layer are sequentially formed on a support. What you have done is known. In this color thermosensitive recording material, the lower thermosensitive coloring layer has lower thermal recording sensitivity, and each thermosensitive coloring layer has a characteristic of being photo-fixed with a specific ultraviolet ray.

In the case of thermally recording a multicolor image on the color thermosensitive recording material, a thermal head having a plurality of heating elements arranged in a line is used, and the color thermosensitive recording material and the thermal head are moved relatively to each other. First, the uppermost yellow thermosensitive coloring layer (first layer) is thermally recorded with a thermal head. After the thermal recording of the yellow image, light in the wavelength range in which only the uncolored diazonium salt compound in the yellow thermosensitive coloring layer is photolyzed is irradiated to photofix the yellow thermosensitive coloring layer. Next, the magenta thermosensitive coloring layer (second layer) is subjected to thermal recording by using heat energy higher than that of the yellow thermosensitive coloring layer, and then only the uncolored diazonium salt compound of the magenta thermosensitive coloring layer is recorded. The light is fixed by irradiating it with light in the wavelength range where it is photolyzed. After that, the cyan thermosensitive coloring layer (third layer) is thermally recorded using the largest thermal energy. Finally, light is fixed in the cyan thermosensitive coloring layer by irradiating light in a wavelength range in which only the uncolored diazonium salt compound remaining therein is photodecomposed. If the third layer is a non-diazonium salt cyan thermosensitive coloring layer, the final light fixing is not necessary.

In the color thermal recording method, one thermal head is used to pass the color thermal recording material three times to thermally record each layer (three-pass system), and three thermal heads are used for color recording. Pass through the thermal recording material, 1
There is a method (one-pass method) in which each layer is sequentially subjected to thermal recording by passing once. The 3-pass type color thermal printer requires only one thermal head and has a simple structure, but on the other hand, the color thermal recording material needs to be passed through three times, which requires a long recording time. In addition, the 1-pass type color thermal printer has an advantage that high-speed printing is possible because color recording can be performed in one pass.

[0005]

However, the above-mentioned 1
In the pass-type color thermal printer, since three thermal heads and two fixing lamps are incorporated in one base frame, they are close to each other, and the heat from the fixing lamps causes the head temperature of the thermal head to rise. However, there is a problem in that accurate heat recording cannot be performed by raising the temperature. In addition, a slit-shaped hole is formed in the base frame facing the fixing lamp, and ultraviolet rays are radiated toward the color thermosensitive recording material from this hole. Has a drawback that it is partially blocked by dust and dirt, resulting in uneven fixing.

The present invention is intended to solve the above problems, and prevents uneven fixing due to dust and dirt, and
An object of the present invention is to provide a 1-pass type color thermal printer in which the temperature rise of a thermal head is prevented.

[0007]

In order to achieve the above object, the color thermal printer of the present invention forms an ultraviolet ray transmissive film with alumite, and the ultraviolet ray of each fixing lamp is exposed through the ultraviolet ray transmissive film. Since the irradiation is performed on the sheet, holes that are blocked by dust or dust are unnecessary, and uneven fixing does not occur. Further, the heat emitted from the fixing lamp is dissipated by alumite, which has a high heat dissipation effect, and does not affect the head temperature of the thermal head. Further, the ultraviolet transmitting film is formed by masking an aluminum plate and then anodizing it, and dissolving the other alumite layer and the aluminum plate while leaving only one side of the alumite layer formed on both sides of the aluminum plate. From
It is possible to easily and surely form the ultraviolet ray transmitting film having the heat dissipation effect.

[0008]

EXAMPLES In FIG. 1, a color thermosensitive recording material 10 is
It is sent at a constant speed by the pair of carrying rollers 11 and 12. Three platen rollers 13, 14 and 15 are sequentially provided between the transport roller pairs 11 and 12. In addition, the recording material 10 is provided on the platen rollers 13 to 15.
From the upstream side in the conveying direction, a thermal head 16 for yellow thermosensitive coloring, a thermal head 17 for magenta thermosensitive coloring, and a thermal head 18 for cyan thermosensitive coloring are sequentially provided. Each thermal head 16, 17, 18 is attached to a base frame 19. In addition, the thermal head 16
A heating element array (not shown) is provided at each lower end of each of to 18. As is well known, the heating element array is formed long in a direction orthogonal to the transport direction of the recording material 10, and a plurality of heating elements are arranged in a line.

A yellow layer fixing lamp 25 is provided between the thermal heads 16 and 17, and a magenta layer fixing lamp 26 is provided between the thermal heads 17 and 18.
The yellow layer fixing lamp 25 has an emission peak of about 420.
The magenta layer fixing lamp 26 is an ultraviolet lamp having an emission peak of about 365 nm. A reflective film 25 is formed on 3/4 of these peripheral surfaces.
a and 26a are applied, and ultraviolet rays are radiated toward the recording material 10 from the 1/4 area facing the platen rollers 13 to 15 side. In addition, each of these lamps 25, 26
Is shielded from light by partition plates 27a and 27b provided on the base frame 19, so that the thermosensitive coloring layer of that color is not optically fixed before thermal recording.

A base frame 1 facing the fixing lamps 25 and 26
Aluminum plates 28 and 29 having a high heat radiation effect are fixed to the plate 9. As shown in FIG. 2, a transparent alumite layer 30 having a length of, for example, 1 mm and a thickness of 100 μm, which is long in the direction perpendicular to the drawing, is provided in the central portion of the aluminum plates 28, 29, and the fixing is performed through the alumite layer 30. Lamp 2
The recording material 10 is irradiated with ultraviolet rays of 5, 26.

A method for forming the alumite layer 30 is shown in FIG.
It will be described with reference to (H). (H) shows the end surface III-III of the aluminum plate 28 shown in FIG. 2, and (A) is the aluminum base plate 31 which is the basis thereof. This aluminum base plate 3
A groove 31a having substantially the same shape as that of the alumite layer 30 is formed in the central portion of No. 1 in advance. First, in order to improve the adhesion of the masking, the aluminum base plate 3
1 is put, and electricity with a current density of 0.5 A / dm ² is added to this
After flowing for 0 minutes to perform anodization, a thin alumite layer 32 is formed on the entire surface of the aluminum base plate 31, as shown in FIG.

Next, as shown in (C), the aluminum base plate 3
Masking processing is performed except for the central portion of 1. In this masking process, an acid resistant material such as rubber is brush-coated to form the acid resistant film 33. Thereafter, the masked aluminum base plate 31 is anodized at a current density of 2.0 A / dm ² , and as shown in (D), the alumite layer 34,
35 is formed.

As shown in (E), after performing a masking process for forming an acid resistant film 36 on the surface of the alumite layer 34, the alumite layers 32, 35 are dissolved from the back surface with NaOH (see (F)). In addition, the groove 31b is 50
When dissolved with% HCl, as shown in (G),
Only the alumite layers 32 and 34 and the acid resistant film 36 remain in the central portion of the aluminum base plate 31. Finally, acid resistant film 3
When 3, 36 are removed, as shown in (H), only the transparent alumite layer 30 composed of the alumite layers 32, 34 remains in the central portion of the aluminum base plate 31, from which the fixing lamps 25, 26 are removed. It becomes possible to transmit the ultraviolet rays.

FIG. 4 shows an example of the color thermosensitive recording material 10. The cyan thermosensitive coloring layer 4 is formed on the support 40.
1, magenta thermosensitive coloring layer 42, yellow thermosensitive coloring layer 4
3 and the protective layer 44 are sequentially provided in layers. These thermosensitive coloring layers 41 to 43 are layered from the surface in the order of thermal recording. For example, in the case of thermal recording in the order of magenta, yellow, and cyan, the yellow thermosensitive coloring layer and the magenta thermosensitive coloring layer. And are interchanged. These thermosensitive coloring layers 41 to 43 have higher coloring thermal energy as they are deeper, so that the three coloring thermosensitive coloring layers 41 to 43 can be selectively recorded by changing the coloring thermal energy. An intermediate layer (not shown) is preferably provided between each color forming layer.

Next, the operation of this embodiment will be described. When the recording position of the recording material 10 is positioned on the thermal head 16 by the conveying roller pair 11, the thermal head 16 is driven by a yellow thermosensitive color development signal from a well-known drive circuit to thermally record a yellow image for one line. Further, in synchronization with the feeding of the recording material 10, the thermal head 16 is driven by the thermosensitive coloring signal of the next line, so that the yellow image is recorded on the recording material 10 one line after another. When this yellow image comes under the fixing lamp 25, the emission peak from the fixing lamp 25 is about 420.
Ultraviolet rays of nm are irradiated through the alumite layer 30 and photofixed.

Since the alumite layer 30 is porous and has a high heat dissipation effect, the thermal heads 16 to 18 are used for the fixing lamp 2.
Fixing lamp 2 despite being near 5, 26
Accurate thermal recording is performed without being heated by heat from 5, 26. Further, since the aluminum plate 28 does not have an opening, it is possible to prevent the opening from being clogged with dust and the light amount being partially reduced to cause uneven fixing.

Next, when the tip of the yellow image reaches the heat generating portion of the thermal head, the thermal head 17 similarly records a magenta image line by line. During this recording, thermal recording and fixing of the yellow image and thermal recording of the magenta image are performed in parallel. This magenta image is also optically fixed by the fixing lamp 26. At the time of recording this magenta image, the yellow thermosensitive coloring layer 43 is also heated, but since the coloring ability is already lost, the yellow thermosensitive coloring layer 43 does not develop color.

Similarly, a cyan image is thermally recorded line by line by the thermal head 18. At this time, thermal recording of the yellow image, magenta image, and cyan image and fixing of the yellow image and magenta image are all performed in parallel. The cyan thermosensitive coloring layer 41 has a considerably high thermal energy required for thermosensitive coloring, and does not develop color in a normal storage state. Therefore, optical fixing is omitted for the cyan thermosensitive coloring layer 41. In this way, each thermal head 16
When the recording material 10 passes once through .about.18, the color image is thermally recorded.

In the embodiment described above, the aluminum plate 2 is used.
Although the alumite layer 30 of No. 8 was formed into a linear elongated shape as shown in FIG. 2, as shown in FIGS. 5 (A) and 5 (B),
The parallelogram-shaped alumite layer 46 and the alumite layer 47 having a long hole having a semicircular end portion may be formed, and a large number of these may be arranged. The present invention is of course not limited to the numerical values of the width and thickness of the alumite layer in the above examples.

[0020]

As described above, according to the color thermal printer of the present invention, the recording material is irradiated with the ultraviolet rays of the fixing lamp through the alumite. Therefore, unlike the conventional case, the amount of light is partially reduced by clogging the holes for passing ultraviolet rays with dust and dirt, and uneven fixing does not occur. Also, since alumite has a very high heat dissipation effect,
The heat of the fixing lamp does not affect the thermal head, and accurate image recording can be performed. In addition, the alumite is formed by dissolving the other alumite layer and the aluminum plate, leaving only one side of the alumite layer formed on both sides of the aluminum plate after masking the aluminum plate and anodizing. It is possible to easily and surely form a thin ultraviolet ray transmissive alumite film having a heat dissipation effect.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a main part of a color thermal printer of the present invention.

FIG. 2 is a schematic plan view showing the shapes of an aluminum plate and an alumite layer according to the present invention.

FIG. 3 is an end view sequentially showing a process of forming an alumite layer.

FIG. 4 is an explanatory diagram showing an example of a layer structure of a color thermosensitive recording material.

FIG. 5 is a schematic plan view showing the shape of another alumite layer.

[Explanation of symbols]

 10 Color Thermal Recording Material 16-18 Thermal Head 25, 26 Fixing Lamp 28, 29 Aluminum Plate 30, 32, 34, 35, 46, 47 Alumite Layer

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shota Namioka 3-13-45 Izumi, Asaka-shi, Saitama Fuji Photo Film Co., Ltd.

Claims (2)

[Claims] 1. A plurality of thermal heads for thermally recording on each thermosensitive coloring layer, using a color thermosensitive recording material having at least three thermosensitive coloring layers layered thereon, and a specific ultraviolet ray for each thermosensitive coloring layer after thermal recording. A plurality of fixing lamps for irradiating and fixing by light are arranged in close proximity, and these and the color thermosensitive recording material
A color thermal printer that obtains a hard copy of a color image by moving it relative to the color thermal printer by forming an ultraviolet ray transmissive film with alumite and irradiating the ultraviolet ray of each fixing lamp to the color thermal recording material through this ultraviolet ray transmissive film. And color thermal printer. 2. The ultraviolet ray transmissive film is formed by masking an aluminum plate and then anodizing the aluminum plate to dissolve only one side of the alumite layer formed on both sides of the aluminum plate and dissolve the other alumite layer and the aluminum plate. The color thermal printer according to claim 1, wherein the color thermal printer is formed by the following method.