JPS5841496B2 - Metal thin film heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a low melting point metal thin film heating device for preheating the metal thin film to increase sensitivity when forming an image on the low melting point metal thin film.

In recent years, films in which a thin metal film layer of bismuth, tellurium, etc. is formed on a base layer such as polyester film have been developed as recording media for various subjects.

Such a film can be recorded only when energy is applied above a threshold value, and FIG. 1 shows a general arrangement for transfer recording from a master film.

Here, 1 is a base layer such as a polyester film, 2 is a thin metal film layer with a low melting point such as bismuth, which is formed on the base layer 1, and 3
is a protective layer formed on the thin film layer 2, and these layers constitute a film 4 as a recording medium.

Master film 5 to be transferred and recorded on this film 4
are overlapped and pressed tightly together using a film presser 6.

Reference numeral 7 denotes a light source, which has sufficient radiant energy to melt the thin film layer 2 when it is irradiated onto the thin film layer 2.

However, the light source 7 requires extremely large energy, and in this state, the thin film layer 2 is not easily melted and the sensitivity of the film 4 is also low.

Also, this light source 7 uses a flash lamp,
As shown in FIG. 2, the amount of light on the film 4 decreases as the distance from the light source 1 increases.

For this reason, there is a possibility that a lack of energy will occur in a position far from the light source 7, that is, in the peripheral area of the film 4, and the film 4 will not be uniformly irradiated with energy, which will appear uneven after transfer.

The object of the present invention is to eliminate the above-mentioned drawbacks, and to preheat the thin film layer before irradiation with a light source, and to preheat the thin film layer in such a way as to give a temperature gradient that is contrary to the light intensity distribution of the light source. To provide a metal thin film heating device which facilitates melting of the thin film layer to increase film sensitivity, and which uniformly imparts energy to the film by light irradiation from a light source and performs even image transfer. It is.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 3 is a diagram showing a temperature gradient for preheating the film before irradiation with light from a light source.

In the present invention, since the irradiation energy distribution from the light source 7 is as shown in FIG. 2, it is necessary that energy be uniformly applied to the film 4 during transfer during light irradiation.

Therefore, in order to compensate for the irradiation energy distribution of the light source 7, it is necessary to provide opposing temperature gradients.

That is, as shown in FIG. 3, the position on the film 4 farthest from the light source 7 is preheated to the highest temperature, and the position on the film 4 closest to the light source 7 is preheated to the lowest temperature.

FIG. 4 shows an embodiment of the heating device of the present invention for heating the film 4 with the temperature gradient shown in FIG.

In this N, the same reference numerals are used for the same parts as in FIG. be.

Reference numeral 9 denotes a heating heater, which is wound around the metal base 8.

Next, in order to transfer the pattern of the master film 5 onto the film 4 using this heating device, the film 4 and the master film 5 are placed one on top of the other on the metal base 8 and brought into close contact with the film presser 6.

At this time, since a heating heater 9 is wrapped around the metal base 8, the surface of the base 8 on which the film 4 is placed has the highest temperature near the periphery, and the temperature decreases as it gets closer to the center. It's getting lower.

That is, the base 8 has a temperature gradient as shown in FIG. 3, and therefore the metal thin film layer 2 of the film 4 is also heated to the same temperature gradient.

At this step, light is irradiated by the light source 7 to melt the thin film layer 2.

Here, the temperature of the base 8 must be kept within a range that does not deteriorate the base layer 1, and energy above the threshold value is applied to the thin film layer 2 only by irradiation with the light source 7.

At this time, the mounting surface of the base 8 on which the film 4 is mounted and the light source 7
The positional relationship with is set as follows.

That is, in the temperature distribution shown in FIG. 3, the light source 7 is placed directly above the portion of the mounting surface where the temperature is the minimum.

By satisfying the relationship between the two, the second
The vertical axes of light intensity and temperature in the figure and FIG. .

- As a modification of the above-described embodiment, a coil is wound around the metal base 8, a high-temperature current is passed through the coil from a high-frequency power source, and the base 8 is heated by induction heating using the alternating magnetic field of the coil. You can.

In this case, the temperature gradient of the base 8 becomes a parabola, and the base 8 itself can be quickly heated.

It should be noted that the heating device used in the present invention is not limited to the above-mentioned embodiments, and can be modified in various ways. Any material may be used as long as it can provide a high temperature gradient.

According to the present invention described above, it is possible to compensate for unevenness in illuminance on the film surface due to the positional relationship between the light source and the film after transfer, and it is possible to always make the energy on the film surface uniform when the light source is emitted.

Also, since the metal thin film layer of the film is preheated,
Even if the energy of the light source is small, the thin film layer will easily melt,
The sensitivity of the film will also be improved.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the general arrangement when recording on a metal thin film layer, Figure 2 is a diagram showing the energy distribution on the film by a light source, and Figure 3 is a diagram when preheating the film according to the present invention. FIG. 4 is a diagram showing an embodiment of the heating device according to the present invention.

Claims (1)

[Scope of Claims] 1. An apparatus for thermal development recording by heating a film having a metal thin film layer that is melted by irradiation with energy equal to or higher than a specific threshold f, comprising a mounting surface on which the film is mounted. a metal base that is shaped like a metal base; a heater that is wound around the side surface of the metal base so that an inverted mountain-shaped thermal energy distribution is formed on the mounting surface; 1. A heating device for a metal thin film, comprising a light source for irradiating the film, which is placed directly above the placement surface to reach a certain temperature. 2. An apparatus for thermal development recording by heating a film having a metal thin film layer that melts when irradiated with energy above a specific threshold, comprising: a metal base having a mounting surface on which the film is mounted; An induction heating coil is wound around the side surface of the metal base so that an inverted mountain-shaped thermal energy distribution is formed on the mounting surface; 1. A heating device for a metal thin film, comprising a light source for irradiating the film, which is placed directly above the writing surface.