JPS59196294A - Image forming method - Google Patents

Abstract

PURPOSE:To enable high speed recording by reduced energy and to enhance image quality, by imparting energy to an ink film having a thin layer comprising a microcapsule having liquid ink entrapped therein in such a state that an object to be transferred is closely contacted with said film. CONSTITUTION:Microcapsules 4 each having liquid ink trapped therein are applied to a support layer 1 comprising polyester or polyimide in a thin film form by directly adhering the same or applying the same in a state dispersed in a binder to form a microcapsule thin layer 2. The membrane of each microcapsule 4 consists of a nylon membrane 5 and a synthetic two-molecule membrane 6 and, when heated to 40 deg.C or more, discharge ink 7 out of the capsule. Thus formed ink film 3 having the microcapsule thin layer 2 is brought into close contact with recording paper 8 and both of them are passed between a thermal head 9 and a pressure roll 10 and heat energy is imparted to the film 3 from the head 9 corresponding to an image signal to form an image. In this case, large heat energy is not required and a laser beam source may be used.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an image forming method that can be applied to facsimiles, computer printers, and the like.

Prior Art Conventionally, this type of image forming method includes a thermal transfer method,
Electric transfer methods and the like are known. For these methods,
Since the solid ink of the ink film is melted by the heat from the thermal head or the Joule heat caused by the current flowing from the recording electrode, the recording energy is inevitably increased. For example, in the case of the current transfer method, a current of about 31 mA per dot must be passed for about 1 to 2 m5 ec to heat the solid ink to over 100 degrees Celsius.

Therefore, the recording speed cannot be increased very much, and there is a limit to increasing the density of images. Further, even though the ink is solid, since this solid ink layer comes into contact with the entire surface of the recording paper, some scumming is unavoidable.

Purpose The present invention has been made in view of the above points, and an object of the present invention is to provide an image forming method that can perform recording with less energy, has a high recording speed, and can improve image quality with less background smudge. purpose.

Structure A first embodiment of the present invention will be described based on FIGS. 1 and 2. FIG. First, in this embodiment, as shown in FIG. 1, an ink film 3 consisting of a support layer 1 and a thin microcapsule layer 2 is used.

Here, the support layer 1 may be made of polyester, polyimide, polysulfone, etc., like the support layer of the ink film in thermal transfer. However, according to this embodiment, as will be described later, it is not necessary to raise the temperature of the ink film 3 as much as in the conventional case, so it may be made of materials with relatively low heat resistance, such as nylon or vinyl chloride. The microcapsule thin layer 2 is formed by directly adhering a large number of microcapsules 4 to a thin layer on the support layer 1 or coating the microcapsules by dispersing them in a binder. The microcapsule 4 has recently been developed, and as shown in FIG. 2, the microcapsule 4 has a liquid ink 7 enclosed in a shell made of a nylon membrane 5 and a synthetic bilayer membrane 6. This synthetic bilayer membrane 5 has micropores present in the nylon membrane 5 in the form of 51, and this synthetic bilayer membrane 6 has a two-layer structure in which dialkyl ammonium salt molecules face each other with their hydrophobic groups. , has heat sensitivity,
At room temperature, almost no ink 7 comes out, but when heated above 140° C., ink 7 is released outside the microcapsules 4, indicating a valve action.

Image formation uses such an ink film 3.
Proceed as shown in the figure. That is, the ink film 3
The side of the microcapsule thin layer 2 is placed on the recording paper 8 which is the transfer target
in close contact with (or close to) the thermal head 9.
When the ink film 3 is passed between the pressure rollers 10 and the signal generator 11 applies thermal energy (release energy) according to the image signal from the thermal head 9 to the ink film 3, the ink 7 is released from the microcapsules 4 only in the heated portion. The image is then transferred onto the recording paper 8 to form a visible image.

Therefore, according to the method of this embodiment, the ink 7 that forms a visible image is in a liquid state from the beginning, and the thermal energy by the thermal head 9 is transferred from the ink 7 from the microcapsules 4.
Conventional thermal transfer to melt the solid ink as it is used to control the release of (i.e. the valve action of the synthetic bilayer membrane 6).

It does not require much energy compared to the electrical transfer method. Therefore, the thermal energy manual means may be a laser light source or the like. As a result of not requiring a large amount of energy, the recording speed can be increased and the density of one image can be increased. Further, when thermal energy is applied to the ink film 3, the shells of the microcapsules 4 themselves are not destroyed, so that the shell material does not adhere to the recording paper 8. And microcapsule 4
Since it has sufficient mechanical strength, it will not be destroyed by pressure contact of the thermal head 9, the liquid ink 7 contained therein will not leak out, and the recording paper 8 will not be smudged.

Next, a second embodiment of the present invention will be described with reference to FIG. This embodiment is basically the same as the previous embodiment, but uses the light energy from the light source 12 as the emitted energy. Therefore, the synthetic bilayer membrane 6 in this example has a two-layer structure in which molecules of dialkyl ammonium salt or dialkyl phosphate containing an azo group face each other with their hydrophobic groups, and is photosensitive. Almost no ink 7 comes out, but when exposed to light, it reacts and the ink 7
It exhibits a valve action that releases the microcapsule 4 to the outside of the microcapsule 4. Here, as the light energy manual means, a laser light source or a combination of an ordinary light emitting lamp and a light shutter element can be used.

Therefore, if a laser light source is used as the emission energy source, it can be applied to both embodiments, but if it is used in photon mode instead of heat mode as in the second embodiment, higher speed and image quality can be achieved.

Effects Since the present invention is configured as described above, it is possible to form an image with less energy, thereby achieving high-speed recording and high-density images. This can be prevented and image quality can be improved.

[Brief explanation of drawings]

1 to 3 show a first embodiment of the present invention, in which FIG. 1 is a side view of an ink film, FIG. 2 is a sectional view of a microcapsule, FIG. 3 is a schematic side view, and FIG. The figure is a schematic side view showing a second embodiment of the present invention. 1... Support layer, 2... Microcapsule thin layer, 3
... Ink film, 4. Microcapsule, 7.
...Liquid ink, 8...Recording paper (transferred material) Applicant: Ricoh Co., Ltd. - ~Figure 1 - Figure 0

Claims (1)

[Claims] 1. An ink film is provided in which a thin layer of microcapsules made up of a large number of microcapsules containing liquid ink is provided on a support layer, and the thin microcapsule layer side of this ink film is brought close to the object to be transferred. Alternatively, an image forming method is characterized in that the ink film is brought into close contact with the microcapsules, and the ink is released from the microcapsules by applying release energy to the ink film from the support layer side in accordance with an image signal, thereby forming a visible image on the transfer target. 2. The image forming method according to claim 1, wherein the emitted energy is thermal energy. 3. The image forming method according to claim 1, wherein the emitted energy is light energy.