JPH07242006A - Thermal transfer recorder - Google Patents

Abstract

(57) [Summary] [Purpose] A high-quality color image is easily produced by appropriately vaporizing a transfer dye according to an image signal and performing transfer recording on photographic paper. [Structure] The dye containing portion 2 is formed into a flat housing shape, and contains a transfer dye in a molten state to form a transfer dye layer 22. A part of the upper surface of the dye containing section 2 is opened to a predetermined area to form an opening 2a, and the transfer section 3 is formed by the opening 2a and the area inside the dye containing section 2 below the opening 2a. To do.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is to transfer a transfer dye to an object to be transferred according to an image signal by an appropriate heat source.
The present invention relates to a thermal transfer recording device that forms a transfer image of continuous gradation.

[0002]

2. Description of the Related Art Conventionally, an object to be transferred such as photographic paper and a thermal transfer recording medium such as an ink sheet are superposed and heated selectively by a heating means such as a laser or a thermal head according to an image signal. However, a thermal transfer recording apparatus that records an image by transferring a transfer dye from a thermal transfer recording medium to a transfer target is widely used.

Among them, in a so-called sublimation type thermal transfer recording apparatus using a heat diffusible dye such as a sublimation dye as a transfer dye, the apparatus is small in size, easy to maintain, has immediacy, and records according to heating energy. Since gradation can be obtained in images and high-quality images comparable to silver halide color photographs can be obtained, in recent years, they have attracted attention as a technique for hard copying images in video cameras, televisions, computer graphics, etc. There is.

However, conventionally, as an ink ribbon used for such thermal transfer recording, a transfer dye is mixed with an appropriate binder resin in a weight ratio of about 1: 1 and a thickness of about 1 μm is formed on a substrate such as a polyester film. The one applied to is used. However, since this ink ribbon is usually disposable, a large amount of waste is generated, which is regarded as a problem from the viewpoint of environmental protection.

Therefore, it has been attempted to improve the utilization efficiency of the thermal transfer recording medium, and one satisfying the demand is a transfer dye of the thermal transfer recording medium such as a transfer dye layer reproducing method or a multiple transfer dye layer constitution method. Examples thereof include a method of reproducing a layer so that it can be repeatedly used, and a method of effectively using a thermal transfer recording medium like a relative velocity method.

[0006]

However, in any of the above-mentioned methods, since the dye is transferred by pressing the transfer dye layer onto the photographic paper, when the color image is obtained, the already transferred dye is transferred. The problem of irreversible transfer to the dye layer, which deteriorates the image quality and damages the image, is unavoidable.

Therefore, an apparatus has been proposed in which a gap is provided between the transfer dye layer and the printing paper to transfer the dye without bringing the transfer dye layer and the printing paper into contact with each other.
In this case, the transfer dye is supplied to the transfer section by flowing in a molten state or by being continuously coated on an appropriate substrate and moving the substrate to the transfer section. Then, based on the image signal, the transfer dye is vaporized by a heating means such as a laser and transferred onto the printing paper.

However, when the transfer recording is carried out by this apparatus, since the binder is not contained in the transfer dye, for example, when the laser irradiation is performed, the temperature generated by the difference in surface tension between the heated portion and the non-heated portion of the transfer dye. The gradient causes lateral movement of the transfer dye, causing the transfer dye to escape to the surroundings. Therefore, a problem occurs that the transfer dye is not vaporized properly.

As described above, a space is provided between the transfer dye layer and the printing paper, and the transfer dye in a molten state is vaporized by a heating means such as a laser according to an image signal, and the transfer dye is transferred and recorded on the printing paper. In the thermal transfer recording apparatus having the above-mentioned structure, reverse transfer does not occur in the transfer dye layer during transfer recording, but it is very difficult to vaporize the transfer dye as desired. .

The present invention has been made in view of the above problems, and an object of the present invention is to appropriately vaporize a transfer dye according to an image signal and perform transfer recording on photographic paper to obtain a high quality image. It is an object of the present invention to provide a thermal transfer recording device that enables easy production of color images.

[0011]

According to the present invention, an air gap is provided between a transfer dye layer and a recording medium to be transferred, the transfer dye is melted and supplied to a transfer portion, and then this is vaporized by a heating means. The present invention is intended for a thermal transfer recording device for transferring onto a recording medium. In the present invention, a spatial structure having a distance d represented by the following formula is formed in the transfer portion where the melted transfer dye is vaporized. Where α, η, h, Δx,
ΔT and Δt are the temperature coefficient of the surface tension of the transfer dye, the viscosity coefficient of the transfer dye that is not heated, the thickness of the transfer dye layer, the diameter of the heating spot, the temperature difference between the transfer dye and the surroundings caused by heating, and the heating time. Is.

D <(h / 4η) (αΔT / Δx) Δt (1) That is, the thermal transfer recording apparatus according to the present invention has the above (1).
A spatial structure having a distance d represented by the formula is formed and configured.

In this case, the spatial structure may be configured as an opening in the transfer section.

Further, the spatial structure may be constructed as a barrier.

At this time, the spacing d of the spatial structure is set to a value not less than the diameter Δx of the heating spot.

[0016]

In the thermal transfer recording apparatus according to the present invention, since the spatial structure having the interval d represented by the above formula (1) is formed, the transfer that occurs when the transfer dye melted by the heating means is vaporized. The lateral movement of the dye is suppressed.

That is, a gap is provided between the transfer dye layer and the printing paper, and the transfer dye in a molten state is heated by a heating means to vaporize it without contacting the transfer dye layer and the printing paper. When the image is transferred from the above to the photographic paper through the void, it is necessary to instantly raise the temperature of the transfer dye to vaporize it, and a difference in surface tension between the heated portion and the non-heated portion of the transfer dye causes a temperature gradient. Occurs, and the transfer dye in the heated portion moves laterally. The movement distance g of this movement that occurs during the heating time Δt is expressed by the following equation.

G = (h / 4η) (αΔT / Δx) Δt (2)

At this time, in the present invention, the distance d between the spatial structures provided in the transfer portion is smaller than the moving distance g as shown in the equation (1). The action of blocking the transfer dye in the lateral direction works promptly. Therefore, the lateral movement of the transfer dye, which is inevitably generated by instantaneously heating the transfer dye, is almost completely suppressed, and the decrease in the transfer amount onto the printing paper is prevented.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of a thermal transfer recording apparatus according to the present invention will be described below with reference to the drawings. This thermal transfer recording apparatus superimposes a transfer target such as photographic paper and a thermal transfer recording medium such as an ink sheet, and selectively heats it in accordance with an image signal by using a heating unit such as a laser or a thermal head. In accordance with an image signal, a transfer dye is transferred from a thermal transfer recording medium to a transfer target to record an image.

First, the first embodiment will be described. This first
As shown in FIG. 1, a main part of the thermal transfer recording apparatus according to the embodiment is a semiconductor laser 1 as a heating means for vaporizing a transfer dye in a molten state, and a glass dye containing part for containing the transfer dye. 2 and.

The transfer dye has a temperature coefficient of surface tension α = 0.1 dyn / cm at a temperature of 250 ° C. and a temperature of 160 ° C.
Trade name HSR203, a disperse dye manufactured by Mitsubishi Kasei Co., Ltd., which has a physical property constant of viscosity coefficient η = 0.2P at ℃
2% by weight of HM1225 (trade name, manufactured by Mitsui Toatsu Co., Ltd.) as a laser light absorber was added to 1 and heated to 160 ° C. to be in a molten state.

The semiconductor laser 1 has an emission wavelength of 780n.
m, an output of 40 mW, and a diameter Δx of a laser spot that is a heating spot is 20 μm, and a laser beam of a pulse as shown in FIG. Here, in the pulse in the figure, when the duty ratio exceeds 60%, it is regarded as continuous heating. Therefore, in this example, the heating time, that is, the irradiation time Δt is set to 1 ms. At this time, the temperature difference between the transfer dye heated by the irradiation of the semiconductor laser 1 and the non-heated portion around it was ΔT = 200 ° C.

The dye containing section 2 has a flat housing shape and contains a transfer dye in a molten state to form a transfer dye layer 22. An opening 2a is formed by opening a part of the upper surface of the dye containing section 2 in a predetermined area, and the transfer section 3 is formed by the opening 2a and the area inside the dye containing section 2 below the opening 2a. .

That is, in the first embodiment, the opening 2a has a spatial structure of the transfer portion 3, and the distance d between the openings 2a is 3d.
= 60 μm. Here, the distance d needs to be equal to or larger than the diameter Δx of the heating spot. The thickness h of the transfer dye layer 22 is the distance from the bottom surface of the dye containing portion 2 to the liquid surface of the opening 2a, and here the thickness h of the transfer dye layer 22 is 10 μm. Therefore, according to the equation (2), the lateral movement distance g of the transfer dye of the heated portion, which occurs during the heating time Δt, is g = 125 μm. That is, the distance d between the openings 2a, which is the spatial structure of the transfer section 3,
Is a half of the above-mentioned moving distance g.

Then, a spacer 12 is provided along the peripheral edge of the opening 2a to form a void portion 13, and a photographic printing paper 14 as a transfer target is placed on the spacer 12. Therefore, the transfer section 3 and the photographic printing paper 14 are not brought into contact with each other, and the transfer section 3 and the photographic printing paper 14 are arranged at a predetermined interval by the void section 13.

In the thermal transfer recording apparatus according to the first embodiment, since the opening 2a having a spatial structure having the distance d represented by the above formula (1) is formed, it is melted by the laser semiconductor 1. The lateral movement of the transfer dye that occurs when the transfer dye is vaporized is suppressed.

That is, the gap portion 13 is provided between the transfer dye layer 22 and the printing paper 14, and the transfer dye layer 22 and the printing paper 14 are provided.
When the transfer dye in a molten state is heated and vaporized by the laser semiconductor 1 without being brought into contact with and when the image is transferred from the transfer section 3 to the photographic paper 14 through the void section 13,
Since it is necessary to instantly raise the temperature of the transfer dye and vaporize it, a difference in surface tension between the heated portion and the non-heated portion of the transfer dye causes a temperature gradient, and the transfer dye in the heated portion moves laterally by a moving distance g. Just move.

At this time, in the first embodiment, the distance d between the openings 2a, which is a spatial structure provided in the transfer portion 3, is the moving distance g as shown in the above equation (1). Since it is smaller, the action of blocking the transfer dye in the lateral direction works quickly. Therefore, the lateral movement of the transfer dye, which is inevitably generated by instantaneously heating the transfer dye, is almost completely suppressed, and a decrease in the transfer amount onto the printing paper 14 is prevented.

With respect to the above-mentioned spatial structure, the preferable value of the distance d is g / 3 to g compared with the moving distance g.
It is about / 2. If this distance d is larger than the moving distance g, it is impossible to prevent the transfer dye from moving.

When the image transfer amount was measured using the thermal transfer device according to the first embodiment, it was 80 μm per 1 ms.
The result was that the transfer dye corresponding to OD 2.2 was transferred onto the photographic printing paper 14 by the Macbeth densitometer in the area of × 80 μm. The transfer amount increased in proportion to the transfer time.

Here, a comparative example for the above-mentioned measurement of the image transfer amount in the first embodiment will be shown. In this comparative example, the image transfer amount was measured under the same conditions as in the first embodiment except that the distance d between the openings 2a, which is the spatial structure of the transfer portion 3, was 180 μm. OD by Macbeth densitometer in the area of × 80μm
Only the transfer dye corresponding to 1.2 was transferred, and even if the transfer time was increased, the dot diameter on the photographic printing paper 14 was only expanded, and the OD of the dot did not change.

Therefore, according to the thermal transfer recording apparatus in the first embodiment, the distance d between the openings 2a is almost doubled as compared with the case where the distance d is out of the regulation range shown in the equation (1). The image transfer amount can be obtained, and a high-quality color image can be easily produced.

Next, the thermal transfer recording apparatus according to the second embodiment will be described. The same symbols are given to members and the like corresponding to the first embodiment. The second embodiment has substantially the same structure as the first embodiment, but is different in that the spatial structure of the transfer portion 3 is different.

That is, in the thermal transfer recording apparatus of the second embodiment, as shown in FIGS. 3 and 4, the transfer portion 3 has a space above the lower surface of the dye containing portion 2 corresponding to the opening 2a. The barrier portion 21 having a dynamic structure is formed.

The barrier portion 21 is composed of four rectangular barriers 21a to 21d, and the barriers 21a and 21b and the barriers 21c and 21d are each spaced by a distance d = 60 .mu.m, that is, approximately half the moving distance g. They are arranged opposite to each other with a certain value. Here, between the respective barriers which are orthogonal to each other, that is, the four corners of the barrier portion 21 are not blocked and are used as the inflow / outflow portions of the transfer dye. The width of the dye containing portion 2 is 120 μm, and the height of each of the barriers 21a to 21d is greater than 10 μm, that is, greater than the thickness h of the transfer dye layer.

In the thermal transfer recording apparatus according to the second embodiment, since the barrier portion 21 having a spatial structure having the distance d represented by the above formula (1) is formed, it is melted by the laser semiconductor 1. The lateral movement of the transfer dye that occurs when the transfer dye is vaporized is suppressed.

That is, the gap portion 13 is provided between the transfer dye layer 22 and the printing paper 14, and the transfer dye layer 22 and the printing paper 14 are provided.
When the transfer dye in a molten state is heated and vaporized by the laser semiconductor 1 without being brought into contact with and when the image is transferred from the transfer section 3 to the photographic paper 14 through the void section 13,
Since it is necessary to instantly raise the temperature of the transfer dye to vaporize it, a difference in surface tension between the heated portion and the non-heated portion of the transfer dye occurs to generate a temperature gradient, and the transfer dye in the heated portion moves laterally by a distance d. Just move.

At this time, in the second embodiment, the distance d between the barrier portions 21 which are the spatial structures provided in the transfer portion 3 is the moving distance g as shown in the above equation (1). Since it is smaller, the action of blocking the transfer dye in the lateral direction works quickly. Therefore, the lateral movement of the transfer dye, which is inevitably generated by instantaneously heating the transfer dye, is almost completely suppressed, and a decrease in the transfer amount onto the printing paper 14 is prevented.

When the image transfer amount was measured using the thermal transfer device according to the second embodiment, it was 80 μm per 1 ms.
The result was that the transfer dye corresponding to OD 2.2 was transferred onto the photographic printing paper 14 by the Macbeth densitometer in the area of × 80 μm. The transfer amount increased in proportion to the transfer time.

Here, a comparative example for the above-mentioned measurement of the image transfer amount in the second embodiment will be shown. In this comparative example, the distance d between the barrier portions 21, which is the spatial structure of the transfer portion 3, is set to 150 μm, which is larger than the moving distance g, and the image transfer amount is measured under the same conditions as in the second embodiment. As a result, only a transfer dye corresponding to OD1.4 was transferred by a Macbeth densitometer to an area of 80 μm × 80 μm per 1 ms, and even if the transfer time was increased, the dot diameter on the photographic printing paper 14 was expanded. The OD of the dots showed no change.

Therefore, according to the thermal transfer recording apparatus in the second embodiment, the distance d between the barrier portions 21 is about twice as small as that in the case where the distance d is out of the regulation range shown in the equation (1). The image transfer amount can be obtained, and a high-quality color image can be easily produced.

Next, a thermal transfer recording apparatus according to the third embodiment will be described. The same symbols are given to members and the like corresponding to the first embodiment. The second embodiment has substantially the same structure as the first embodiment, but is different in that the spatial structure of the transfer portion 3 is different.

That is, in the thermal transfer recording apparatus of the third embodiment, the transfer portion 3 has a circular portion 31 having a circular spatial structure at one end of the dye containing portion 2 as shown in FIG.
Are formed.

The inner diameter of the circular portion 31 is the interval d as a spatial structure, and this value is 40 μm, that is, about 1/3 of the moving distance g. The width of the dye containing portion 2 other than the position where the circular portion 31 is formed is 80 μm, and is integrally formed with one end of the circular portion 31 via the transfer dye inflow / outflow portion 32 having a width of 20 μm. That is, the circular portion 31 has a shape in which the dye containing portion 2 is formed so as to be constricted in the inflow / outflow portion 32.

In the thermal transfer recording apparatus according to the third embodiment, since the circular portion 31 having the spatial structure having the distance d represented by the above formula (1) is formed, it is melted by the laser semiconductor 1. The lateral movement of the transfer dye that occurs when the transfer dye is vaporized is suppressed.

That is, the gap 13 is provided between the transfer dye layer 22 and the printing paper 14, and the transfer dye layer 22 and the printing paper 14 are provided.
When the transfer dye in a molten state is heated and vaporized by the laser semiconductor 1 without being brought into contact with and when the image is transferred from the transfer section 3 to the photographic paper 14 through the void section 13,
Since it is necessary to instantly raise the temperature of the transfer dye and vaporize it, a difference in surface tension between the heated portion and the non-heated portion of the transfer dye causes a temperature gradient, and the transfer dye in the heated portion moves laterally by a moving distance g. Just move.

At this time, in the third embodiment, the distance d between the circular portions 31, which is the spatial structure provided in the transfer portion 3, is the moving distance g as shown in the above equation (1). Since it is smaller, the action of blocking the transfer dye in the lateral direction works quickly. Therefore, the lateral movement of the transfer dye, which is inevitably generated by instantaneously heating the transfer dye, is almost completely suppressed, and a decrease in the transfer amount onto the printing paper 14 is prevented.

The present invention is not limited to the above-mentioned first to third embodiments, and the spatial structure of the transfer portion 3 is as follows.
Not only the barrier portion 21 and the circular portion 31 but also pillars, grooves, concentric wall portions, or the like may be used to satisfy the above formula (1).

[0050]

According to the thermal transfer recording apparatus of the present invention,
In a thermal transfer recording apparatus in which a gap is provided between a transfer dye layer and a transfer recording medium, the transfer dye is melted and supplied to a transfer unit, and then this is vaporized by a heating means and transferred onto the transfer recording medium. , The temperature coefficient of the surface tension of the transfer dye is α,
The viscosity coefficient of the untransferred transfer dye is η, the thickness of the transfer dye layer is h, the diameter of the heating spot is Δx, the temperature difference between the transfer dye and the surroundings caused by heating is ΔT, and the heating time is Δ.
Since the distance d between the spatial structures provided in the transfer part satisfies d <(h / 4η) (αΔT / Δx) Δt when t, the transfer dye is appropriately vaporized according to the image signal. By performing the transfer recording on the photographic paper in this way, it becomes possible to easily produce a high-quality color image.

Further, according to the present invention, since the spatial structure is constituted as the opening portion in the transfer portion, the transfer dye is appropriately vaporized according to the image signal and transfer recording is performed on the photographic paper, whereby a high quality color image is obtained. It is possible to easily create an image.

Further, according to the present invention, since the spatial structure is used as a barrier, the transfer dye is appropriately vaporized according to the image signal and transfer recording is performed on the printing paper, so that a high quality color image can be easily obtained. It becomes possible to produce.

At this time, since the interval d of the spatial structure is set to a value not less than the diameter Δx of the heating spot, the transfer dye is appropriately vaporized according to the image signal and transfer recording is performed on the photographic paper, so that a high image quality It is possible to easily produce a color image.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a main part of a thermal transfer recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a characteristic diagram showing a temporal change in output of laser light from a semiconductor laser.

FIG. 3 is a plan view schematically showing the spatial structure of a transfer section of the thermal transfer recording apparatus according to the second embodiment.

FIG. 4 is a sectional view schematically showing a spatial structure of a transfer portion of the thermal transfer recording apparatus according to the second embodiment.

FIG. 5 is a plan view schematically showing the spatial structure of a transfer section of the thermal transfer recording apparatus according to the third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor laser 2 Dye accommodation part 2a Opening part 3 Transfer part 11 Lens 12 Spacer 13 Space part 14 Printing paper 21 Barrier part 31 Circular part

Claims (4)

[Claims] 1. A gap is provided between the transfer dye layer and the recording medium to be transferred, and after the transfer dye is melted and supplied to the transfer portion,
In a thermal transfer recording apparatus in which this is vaporized by a heating means and transferred onto a transfer recording medium, the temperature coefficient of the surface tension of the transfer dye: α, the viscosity coefficient of the transfer dye that is not heated: η, the thickness of the transfer dye layer: h, the heating Spot diameter: Δx Temperature difference from the surroundings generated in the transfer dye by heating: ΔT Heating time: Δt, the spacing d of the spatial structure provided in the transfer portion
Is given by d <(h / 4η) (αΔT / Δx) Δt. 2. The thermal transfer recording apparatus according to claim 1, wherein the spatial structure is an opening in the transfer section. 3. The thermal transfer recording apparatus according to claim 1, wherein the spatial structure is a barrier. 4. The thermal transfer recording apparatus according to claim 1, wherein the spacing d between the spatial structures is a value equal to or larger than the diameter Δx of the heating spot.