KR20050112033A - Heat-sensitive and light-sensitive color recording medium and process - Google Patents

Abstract

The present invention provides a recording medium and a recording method thereof. More particularly, the present invention relates to a heat-sensitive, photosensitive multi-color recording medium using the applied thermal energy and the applied light energy as a recording or luminescent source, and a recording method thereof.

The heat-sensitive, photo-sensitive multi-color recording medium and the base layer; A first thermochromic layer, a photosensitive-sensitive composite color developing layer, and a second thermosensitive color developing layer sequentially stacked on the substrate layer are included.

Description

Heat-sensitive and light-sensitive multi-color recording medium and its recording method {Heat-sensitive and light-sensitive color recording medium and process}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium and a recording method thereof, and more particularly, to a multicolor recording medium having at least two layers of a thermochromic layer and a photo-sensitizing layer coated on one surface of a substrate layer, and a recording thereof. It is about a method.

Unlike silver-colored photographs, multi-color recording media are widely used due to the advantage that an individual can freely collect and edit images of his or her desired image. In general, the recording method of such a multicolor recording medium is recorded through a sublimation method using a sublimation thermal transfer film, a laser beam printing method using color toner, and a color inkjet method using an ink cartridge. However, the recording method of the multi-color recording medium as described above has the disadvantage that additional maintenance costs and time are required because the additional consumables such as film, toner and ink must be continuously replaced in the recording apparatus in addition to the recording medium.

Accordingly, there is a growing interest in multicolor recording media that can be used in semi-permanent recording devices that do not require consumables by including all of the color layers in the recording media itself.

U. S. Patent No. 5,667, 943 discloses a recording paper having three heat-color developing layers of yellow, magenta and cyan. In the patent, the thermochromic layer includes an infrared absorber which converts an infrared light source into heat, and thus requires an infrared laser light source having a different wavelength depending on the color, and thus requires a recording device including three infrared laser light sources. There is this.

U. S. Patent No. 6,297, 840 discloses a recording paper and a recording apparatus having a thermochromic layer of yellow, magenta, and cyan having different thermal sensitivities. The recording medium of the patent applies a method of fixing ultraviolet rays immediately after the first and second colors, respectively, in order to prevent unwanted color development of other colors when the second and third colors are expressed. There is a disadvantage in that a complicated recording device having a thermal head and two ultraviolet light sources having different maximum wavelength bands is required.

The technical problem to be solved by the present invention is to solve the above problems and does not require any consumables other than the recording medium, and provides a multi-color recording medium and a recording method capable of recording with a recording device having a simple structure having only two energy sources. I would like to.

The present invention in order to achieve the above technical problem; And a first thermochromic layer, a photosensitive-sensitive composite color layer, and a second thermosensitive color layer sequentially positioned on an upper surface of the base layer.

The first thermochromic layer and the second thermochromic layer positioned on the base layer are colored in different thermal energy regions by two operating modes of the thermal head, and the photosensitive-sensitive composite color layer is latent image by a light source. After this is formed, it is colored by thermal energy.

Preferably, the two thermochromic layers are colored in the low energy region as the lower layer, and the second thermochromic layer is colored in the high energy region as the upper layer.

Here, the thermal energy for color development of the two heat-sensitive color layers can be given different thermal energy by operating by controlling the temperature and time of the thermal head. In other words, when the first heat-sensitive color developing layer is colored, since the color is developed in a low energy region, the color may be expressed by operating the thermal head to heat at a low temperature for a longer time than the second heat-sensitive color developing layer. The coloring layer is not a high temperature that can be developed despite the operation of the thermal head for a long time so that unwanted color development does not occur. On the other hand, in the case of color development of the second heat-sensitive color developing layer, color development occurs by operating the thermal head at a higher temperature for a shorter time than the first heat-sensitive color developing layer, but the short time operation of the thermal head generates sufficient thermal energy to the first heat-sensitive color developing layer. It can't be delivered, and unwanted color development doesn't occur.

However, even if the two thermal coloring layers are colored in different thermal energy regions, when adjacent to each other, unwanted color development may occur when the first thermal coloring layer is colored in the low energy region and the second thermal coloring layer is colored in the high energy region. It is preferable to form a photosensitive-sensitive composite chromophore layer between the two thermochromic layers.

Accordingly, when the second thermochromic layer is operated at a higher temperature than the first thermochromic layer for a short time, there is a photosensitive-sensitive composite color layer between the two thermochromic layers, whereby the first thermochromic layer is present. This can prevent the transfer of high thermal energy to the system, thereby preventing unwanted color development.

After the latent image is formed by the laser light source, the photo-sensitive composite chromophore is expressed in color by thermal energy. Here, the thermal energy for color development of the photosensitive-sensitive composite color layer may be made through preheating during operation of the thermal head for color development of the first photosensitive color layer positioned below the photosensitive-sensitive composite color layer. Here, it is preferable that the photosensitive-sensitized composite chromophore is colored in a heat energy region lower than that of the first thermosensitive chromophore.

Further, by preliminary heating for the color development of the photosensitive-sensitive composite generating layer, the heating time for the generation of the heat energy required for the color development of the first thermal color development layer farthest from the thermal head is saved. You can also reduce the print speed.

Accordingly, the two thermal chromophores and the photo-sensitive composite chromophores are colored in different thermal energy regions, that is, according to the magnitude of thermal energy, such as the second thermal chromophore layer> first thermal chromophore layer ≥ photosensitive-sensitive composite chromophore layer. It is preferable.

In addition, each chromophore expresses different colors, mainly yellow, magenta, and cyan, and the order may be changed as necessary.

The multicolor recording medium may further include an undercoating layer between the base layer and the color developing layer, and further include an intermediate layer between the color developing layers, or further include a back coating layer on a lower surface of the base layer. have. In addition, by further including a protective layer on the second thermal color development layer, it can play a role of controlling the thermal stability, the protection of the color development layer and the glossiness of the surface.

Hereinafter, the thermal, photosensitive multicolor recording medium and the recording method thereof according to the present invention will be described in detail with reference to FIG.

1 is a cross-sectional view illustrating a thermally sensitive, photosensitive recording medium according to an embodiment of the present invention.

Referring to FIG. 1, the photosensitive and photosensitive recording medium forms a base layer 1, a first photosensitive color developing layer 2, a photosensitive-sensitive composite color developing layer 3, and a second photosensitive color developing layer 4.

The base layer 1 may be one selected from the group consisting of various papers, plastic films, paper and plastic film, synthetic paper and photo paper. Here, the thickness of the base layer is not limited, but it is preferable to select 15 to 350 μm so as to be easy to handle and to prevent bending when forming a plurality of coating layers on the base layer.

The photosensitive-sensitized composite chrominance layer 3 positioned between the thermochromic layers 2 and 4 and the thermochromic layer is a layer that expresses different colors in different energy regions, and is mainly a color of yellow, magenta, and cyan. The order of the colors can be changed as needed.

The material of the thermochromic layers 2 and 4 may be formed of a material in which the color of the color is directly or indirectly colored by the thermal energy of the thermal head. For example, a substance that causes color development by the change of the material itself due to thermal energy, a substance that develops due to a change in crystallinity, a substance that develops due to the departure of a living group, an acid and a color precursor generated by heat. The reaction can be formed of one material selected from the group consisting of a material for color development, a microcapsule containing a developer or coupler to develop a leuco dye.

The photosensitive-sensitive color developing layer 3 is formed between the two photosensitive color developing layers 2 and 4, and may be formed of a material in which an image is recorded by a laser light source and a color is expressed by thermal energy. For example, the diazonium compound may be decomposed by an ultraviolet or near-ultraviolet light source, and after the image is recorded, the coupler or developer and the undigested diazonium compound may be colored by thermal energy. Herein, when the ultraviolet light source is 360 nm, the color of magenta may be expressed, and when the near ultraviolet ray is 420 nm, it may be expressed in yellow color.

An undercoat layer 5 may be further included between the base layer 1 and the first thermochromic layer 2. The undercoating layer 5 may improve the coating property and adhesion between the base layer 1 and the color developing layer 2, and may prevent the color-developed material from spreading to the base layer after color development in the color developing layer. It also plays a role. Here, the thickness of the undercoat layer 5 is not limited, but it is not necessary to be thick, it is preferable to stack at 0.5 to 4㎛.

Further, an intermediate layer (6,6 ') between the first heat-sensitive color developing layer (2) and the photo-sensitive composite color developing layer (3) or between the photo-sensitive composite color developing layer (3) and the second photosensitive color developing layer (4). It may further include. The intermediate layers 6 and 6 'serve to prevent the spreading of the colored material after color development, like the undercoating layer 5, as well as to prevent unwanted color development as a continuous color separation layer or a thermal separation layer between the two color development layers. Play a role. In addition, the intermediate layers 6 and 6 'are formed when several layers are obtained through a process of applying and drying each layer, for example, when the adjacent thermochromic layer coating liquid is a similar organic solvent solution. It also serves to prevent damage to the entire layer due to the addition of solvents to the entire layer.

In addition, it is formed on the top of the second thermal color development layer 4 to protect the surface of the thermal color development layer from direct heat of the thermal head, and may further include a protective layer 7 to control the surface gloss. Here, the protective layer 7 may be made of a single layer or several layers depending on the purpose or production method. For example, a UV absorber or UV filter layer may be further included to prevent color change due to daily UV exposure during storage after image recording, and when the protective layer is manufactured through lamination or the like without a coating process. An adhesive layer may be further included.

In addition, a rear coating layer 8 may be further included in the lowermost part of the base layer 1 in order to prevent curling of the recording medium or to improve paper feedability during recording by the recording apparatus.

The method of forming the thermochromic layers 2, 4, the photo-sensitive composite color layer 3 and the protective layer 7 may be laminated by conventional methods. For example, suitable coating methods such as knife coating, vari-bar coating, pure blade coating, rod blade coating, short dwell coating, curtain coating, slot die coating, gravure coating and comma coating Applying the first thermochromic layer 2 to one side of the base layer 1 and drying, and repeatedly applying the photosensitive-sensitive composite color layer 3, the intermediate layer and the second thermochromic layer 4, etc. on the top thereof. It may be formed by a method such as drying, or by coating and drying several layers at the same time through die coating or the like. Here, the protective layer 7 and the back coating layer 8 may be formed of a lamination through lamination.

As described above, in the thermally sensitive, photosensitive multicolor recording medium, a multicolor image can be recorded by a recording device having at least one laser light source and one thermal head required for color development. Here, the laser light source is used for recording at least one photosensitive-sensitized composite chromophore layer, and the thermal head operates in two modes of high temperature-short time and low temperature-long time to produce two layers of photochromic layer and photosensitive- It can be used for color development of the thermosensitive composite chromophore.

As described above, the heat-sensitive, photosensitive recording medium according to the present invention includes at least one photosensitive-sensitive composite color developing layer and two layers of photosensitive color developing layers, thereby having one laser light source and one thermal head required for color development. The production of a multicolor recording medium that can be applied to a relatively simple recording device is also easy.

1 is a cross-sectional view illustrating a thermally sensitive, photosensitive recording medium according to an embodiment of the present invention.

<Explanation of symbols for major symbols in the drawings>

DESCRIPTION OF SYMBOLS 1 Base material layer 2,4 The thermal coloring layer

3: photosensitive-heat developing layer 5: undercoating layer

6,6 ': intermediate layer 7: protective layer

8: back coating layer

Claims (15)

Base layer; And a first thermochromic layer, a photosensitive-sensitive composite color layer, and a second thermosensitive color layer sequentially positioned on an upper surface of the base layer. The method of claim 1, The photosensitive-sensitized composite chromophore layer forms a latent image by a laser light source, and the first photosensitive chromophore layer, the second photosensitive chromophore layer, and the photosensitive-sensitive composite chromophore layer exhibit color by operation of the thermal head. Multi-color recording media. The method of claim 2, And the first heat-sensitive color developing layer and the photosensitive-heat-sensitive composite color developing layer are colored by the operation of a thermal head which is heated at a low temperature for a longer time than the second heat-sensitive color developing layer. The method of claim 1, Wherein the size of the energy region to be colored in each of the color layer (s) is a second thermal color layer> a first thermal color layer> photo-sensitive composite color layer. The method of claim 4, wherein And the first photosensitive color-sensing layer, the photosensitive-sensitive composite color layer, and the second photosensitive color layer express different colors. The method of claim 1, And the base layer is formed of one selected from the group consisting of various papers, plastic films, paper and plastic film, synthetic paper and photo paper. The method of claim 6, And the thickness of the base layer is 15 to 350 mu m. The method of claim 1, And wherein the multicolor recording medium further comprises an undercoat layer between the base layer and the first thermochromic layer. The method of claim 8, And the undercoat has a thickness of 0.5 to 4 mu m. The method of claim 1, And said multicolor recording medium further comprises an intermediate layer between said first and second heat-sensitive color-emitting layers and the photo-sensitive color-emitting layer, respectively. The method of claim 1, And said multicolor recording medium further comprises a protective layer on top of said second heat generating layer. The method of claim 1, The multi-color recording medium further comprises a back coating layer at the bottom of the base layer. The recording method of a multicolor recording medium according to claim 1, wherein the multicolor recording medium is recorded by a recording apparatus having one laser light source and one thermal head. The method of claim 13, An image is recorded on the photosensitive-sensitive composite chrominance layer of the multicolor recording medium by the laser light source, and the first thermochromic layer and the second thermal sensitivity of the multicolor recording medium by thermal energy generated by the operation of the thermal head. A recording method for a multicolor recording medium, characterized by developing a color layer and a photosensitive-sensitive composite color layer. The method of claim 13, And the first heat-sensitive color developing layer and the photosensitive-heat-sensitive composite color developing layer are colored by a thermal head operated for a longer time at a lower temperature than the second heat-sensitive color developing layer.