JPS63101844A - Optical recording method - Google Patents

Abstract

PURPOSE:To form image information only by irradiation with light or heating by patternwise exposing ink contg. a substance whose surface stickiness is changed by light or heat and by carrying out transfer. CONSTITUTION:When azobenzene, spiropyrane and triphenylmethane are irradiated with ultraviolet or visible light or heated, a reversible structural change is caused and the surface wettability is reversibly changed. Such a substance is mixed with a solvent and thermoplastic resin to prepare ink 1 and a change in the surface wettability is utilized as a change in the surface stickiness. The ink 1 is applied to an inking roller 2 and irradiated with ultraviolet rays from an ultra-high pressure mercury lamp 3. The resulting ink image is transferred to plain paper 6 through a silicone rubber roller 4. By this method, transferable image information is formed only by irradiation with light or heating and a stable clear hard copy is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an optical recording method that utilizes a change in surface adhesion of a substance whose chemical structure is changed by light or heat.

(Prior Art) Conventionally, methods for recording visible images on plain paper include electrophotography, impact printers, inkjet methods, and thermal transfer recording methods.

Electrophotography has excellent resolution and gradation, but because the process is complicated, the equipment is large and expensive, and reliability is poor.

Furthermore, inkjet methods and impact printers can record directly onto a recording medium and have a simple process, but they have had many problems such as nozzle clogging, poor gradation, and noise.

Regarding the thermal transfer recording method, although attempts have been made to improve resolution and gradation by devising heads and recording members, it has not yet been possible to obtain images as excellent as those obtained using electrophotography.

In contrast to these recording methods, there is a so-called photothermal recording method in which Joule heat generated by applying a current to a photoconductive layer and making an optical signal based on image information incident thereon is visualized using a thermosensitive recording member.

With this method, images with higher resolution and gradation can be obtained than with conventional recording methods, and the apparatus can be simplified, lowered in cost, and made smaller.

However, in this method, the photoconductive layer directly generates heat, so
When used for a long period of time, defects such as partial loss of photoconductivity or conductivity appear, causing problems in image quality. Furthermore, there have been problems in the past in that devices have often failed due to minute defects during the formation of the photoconductive layer, and the cost of the device has increased.

Furthermore, it is known that surface wetting characteristics change reversibly due to light or heat due to chemical changes caused by light irradiation.
19136, and attempts have been made to use it as an image-forming substrate, but it has the drawback that the reversible change can be stably repeated only about a few dozen times, making it difficult to put it into practical use.

(Objective of the Invention) The present invention has been made in view of the above-mentioned problems, and its purpose is to achieve high productivity and reliability (capable of recording with higher resolution and superior gradation than various conventional recording devices). The object of the present invention is to provide a low-cost, maintenance-free optical recording method.

(Summary of the Invention) The above object of the present invention is to irradiate a developer whose surface adhesion changes due to chemical change due to light or heat with light corresponding to image information, and transfer the portion with strong surface adhesion to a recording medium. This is achieved by recording by doing.

Examples of developer materials whose surface adhesion changes due to chemical structure changes caused by light or heat used in the present invention include azobenzene compounds that undergo reversible trans-cis isomerization when exposed to light or heat, and spiropyran compounds that cause ionic cleavage. , triphenylmethane, etc.

Azobenzene, spiropyran, and triphenylmethane are treated as follows (Table 1) by irradiation with ultraviolet light, visible light, or heating.
(see ). This shows the property that the wettability of the surface changes reversibly.

When azobenzene, spiropyran, and triphenylmethane are irradiated with ultraviolet light, they change to the structure shown on the right side of Table 1, and their wettability increases. That is, azobenzene has a cis type, spiropyran has a zwitterion structure, and triphenylmethane has a cation structure, and the wettability is high.

In order to use the above-mentioned wettability change as a developer that changes surface adhesion, it is necessary to mix it with a solvent or a thermoplastic resin, or use a thermoplastic resin containing an azobenzene group, a spiropyran group, or a triphenylmethane group in its molecule. By using the compound in a liquid or molten state, a change in surface wettability can be used as a change in surface adhesion.

The above liquid or molten developer is coated on the developing ink coating surface, and the surface structure of the developer is changed using light such as ultraviolet light, visible light, infrared light, or a heating head, resulting in changes in wettability. An image is recorded by changing the adhesion to the body and transferring only the recording portion to the recording medium.

In addition, the ink is transferred to the recording medium through an intermediate transfer body whose surface is made of a low surface energy material such as silicone resin or fluororesin, which has a marked difference in adhesion due to changes in the wettability of the ink, and then to a transfer paper. In order to obtain high image quality, it is preferable to transfer the image to

(Example) The present invention will be described in detail with reference to Examples below, but the present invention is not limited to the following Examples (Example 1)...
...See Figure 1 1) Preparation of developing ink 6'-Nitro 1-octadecyl-3,3-dimethylspiro [indoline-2,2'-benzopyran] (Spiropyran) 1.0 parts by weight Polystyrene 2 .5 parts by weight Toluella 3.0 parts by weight Ink 1 was prepared by mixing the above three types at room temperature.

2) Creation of image pattern After applying the above ink 1 to inking roller 2 vv-D3
5 UV rays from 500W ultra-high pressure mercury lamp 3 with filter 3c
When irradiated for 10 seconds from a distance of m, a clear image was obtained in which the irradiated area was colored deep blue.

Note that the inking roller 2 rotates in six directions indicated by arrows.

3) Transfer to intermediate transfer member The above ink image was transferred in contact with a roller 4 having a dimethyl silicone rubber layer on its surface. Note that the intermediate transfer body rotates in the direction of arrow B.

4) Transferring the ink image on the dimethyl silicone rubber and plain paper 6 to the transfer target member
was brought into contact with the press roller 5 to transfer the ink image onto plain paper 6 to obtain a clear image.

Note that the presser roller 5 rotates in the direction of arrow C.

<Example 2> Using almost the same apparatus as in Example 1 1) Developing ink Same as in Example 1 2) Creation of image pattern After applying the above ink 1 to the second inking roller, v■-
D35 filter (made by Toshiba Corporation)
When irradiated for 8 seconds from a distance of m, the entire surface of the recording medium was colored (colored dark blue).

Next, the visible light of the IKW printer lamp 7 is applied to the colored recording medium using the inking roller surface force 1 to 6c.
When exposed for 13 seconds from a distance of m, the exposed area turned colorless.

3) Transfer to the intermediate transfer body 4 Same as Example 1 4) Transfer to the transferred member Same as Example 1 (only the dark blue part is clearly transferred) <Example 3> Another example is shown in Fig. 2 show. 101 Ma developing ink 11
It is a transparent cylinder made of single crystal sapphire, quartz, etc., and has transparency in the ultraviolet region, and the developing ink 11 stored in the developing ink reservoir 12 is applied to the surface of the transparent cylinder 10 by a blade 13 into a conductive layer. applied. Here, the same recording medium ink as in Example 1 is used for development.

The transparent cylinder 10 rotates in the direction of the arrow, and the developing ink is irradiated with ultraviolet light by an ultraviolet light source 14 such as an ultra-high pressure water armor lamp and a condensing mirror 15 provided inside the cylinder. The recording medium ink for development becomes dark blue by irradiation with ultraviolet rays.

After that, this colored recording ink is irradiated by a tungsten lamp 16 and a mirror 17, and an image of a transmission image 18 such as a film is exposed through a lens 19 (in the figure, a condenser lens for condensing illumination light is (omitted). At this time, the ink that has changed to a deep blue color reversibly returns to its original structure and the exposed area changes to colorless, forming a pattern corresponding to the image. The pattern in the dark blue portion is transferred in contact with the surface of the intermediate transfer roller 20, which is made of an ink-adhering surface such as dimethyl silicone rubber.

The recording paper 21 is held between the intermediate transfer roller 20 and the presser roller 22, and is moved in the direction of arrow E, while the dark blue pattern on the surface of the intermediate transfer roller is recorded.

(Effects of the Invention) As described above, by using the present invention, transferable image information can be formed by only light irradiation or heating, and a hard copy of this image can be stably and clearly obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing an example of an apparatus capable of carrying out the method of the present invention, and FIG. 2 is a schematic cross-sectional view showing another example of an apparatus capable of carrying out the method of the present invention. l...Developer 2...Inking roller 3...Light irradiation section 4...Intermediate transfer body 5...
Presser roller 6... Plain paper 10... Transparent cylinder 11... Developing ink 12... Ink reservoir for development 13... Blade 14... Ultraviolet light generation source 15
...Concentrating mirror 16...Tungsten lamp

Claims (1)

[Claims] 1) Changing the surface adhesion by exposing image information to a substance whose surface adhesion changes due to a chemical structure change due to light or heat in a pattern, and transferring only the exposed areas or only the non-exposed areas to the recording medium. An optical recording method characterized by: