JPH1016392A - Laser image forming method and apparatus - Google Patents

Abstract

(57) [Problem] To enable high-speed image formation by transferring electrostatically adsorbed particles from a film by laser ablation. SOLUTION: A charging mechanism 3 charges a transparent film 2 continuously supplied by a film feeding mechanism 1. The charged particles 4 electrostatically adsorb the fine particles 6 in the fine particle supply tank 5, and the fine particles 6 are sent together with the film 2 to the irradiation part of the laser beam 7. The fine particles 6 irradiated with the laser beam 7 are transferred onto an object 8 placed on the opposite surface. An image is formed on the transferred material 8 by moving the transferred material 8 by the transferred material feeding mechanism 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method and apparatus for forming a laser image, and more particularly to an image forming technique using a laser ablation function. For example, the present invention is applicable to image forming methods and apparatuses such as printers and printing machines, as well as marking, repairing, and surface modification.

[0002]

2. Description of the Related Art An image forming method using a laser beam includes an electrophotographic laser process, a thermal transfer process and the like. In the electrophotographic laser process, a laser beam is scanned on a photosensitive drum, a charged image is formed on the photosensitive drum by a photoconductive action, and toner or the like is electrostatically attracted to the charged image.
The electrostatically attracted toner or the like is transferred to the transfer-receiving material. In the thermal transfer process, the material to be transferred is usually supplied in the form of a cartridge in the form of a film, and the material to be transferred is melted or vaporized by a thermal process using laser light, and is transferred to the material to be transferred. In the method using the ablation process,
An abradable material directly applied on a transparent substrate is prepared in advance, and is transferred by an ablation process.

[0003]

In a conventional laser printer or a printing process using a laser, a photoreceptor drum, a developing machine, and the like are required, and it is difficult to reduce the size of the apparatus. There was a problem that development was necessary and cost increased. In addition, since the conventional laser thermal transfer process is a thermal process, it is difficult to increase the transfer speed, and frequent cartridge replacement is required, so that the running cost is high and head scanning is required. Therefore, it has been difficult to increase the printing density. Further, in the method using the ablation process up to now, the material has to be formed on the film in advance, and the film needs to be replaced. Further, in order to ablate a material chemically formed on the film, it is necessary to increase the laser intensity, and the laser light must be in the ultraviolet region. Also, it was necessary to develop a material having a large absorption in the laser wavelength region.

[0004]

According to the first aspect of the present invention, the fine particles electrostatically adsorbed on a film transparent to a laser beam and having an insulating property on a surface, and electrostatically adsorbed on the film. Is scattered from the film by a laser ablation function and is transferred to a material to be transferred.

According to a second aspect of the present invention, there is provided a laser light source capable of scanning, a film transparent to the laser beam and having an insulating property on the surface, a charging mechanism for the film, and fine particles for image formation. The film is charged by the charging mechanism, the image forming fine particles are electrostatically adsorbed on the film, and the electrostatically adsorbed image forming fine particles are laser-ablated with the laser light, and are transferred to a transfer-receiving material. It is characterized by the following.

According to a third aspect of the present invention, in the second aspect, there is provided a continuous film supply mechanism for continuously supplying the film, and a fine particle collection mechanism for collecting the fine particles for image formation remaining on the film. It is characterized by the following.

According to a fourth aspect of the present invention, in the second or third aspect, the intensity of the laser beam is equal to or higher than an ablation threshold of the fine particles for image formation.

The invention of claim 5 is characterized in that, in the invention of claim 2 or 3, the film comprises at least two or more kinds of fine particles having different colors and a film obtained by adding them.

The invention of claim 6 is the invention of claim 2 or 3, wherein two or more kinds of fine particles are alternately formed on the film.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a charge is charged on a transparent film having an insulating surface, and a transfer material (fine particles for image formation) such as toner is electrostatically charged on a part or the whole of the surface. Adsorb. The transfer material is irradiated with laser light from the surface of the sheet on which the transfer material is not adsorbed, and the transfer material is transferred at high speed to the material to be transferred placed opposite to the surface on which the transfer material is adsorbed by the ablation of the laser light. Form an image. In some cases, a transfer material (fine particle) collection mechanism is provided for electrostatically or mechanically removing transfer material (fine particles for image formation remaining on the film) that has not been transferred into the apparatus. Is supplied continuously to supply the transfer material. Further, a pattern of two or more kinds of fine particles having different colors is formed on a film by, for example, electrically controlling the adsorption of the fine particles to form a color image.

In the present invention, since the adsorbed substance (transfer material) is separated from the film by the volume increase (ablation) due to the excitation of the material that has absorbed the laser beam, the transfer is performed at a much higher speed than the thermal process. Becomes possible. Also, since the film and the transfer material are electrostatically adsorbed,
Bonding is weaker than chemical bonding, and peeling is easier. The amount of laser light absorbed can adjust the amount of excitation and scattering speed of the transfer material.By increasing the laser intensity, the transfer material can be scattered with more excess energy and can be fixed directly to the material to be transferred. Become. Further, even when the laser intensity is low, the transfer material is peeled off from the film with a slight increase in volume. Therefore, by using a fixing device, image formation can be performed with a low laser intensity. Generally, coloring molecules such as dyes have absorption in the visible and ultraviolet regions, so that most of the fine particles that can be electrostatically adsorbed to a film can be used in the present invention.

[0012]

FIG. 1 is a flow chart of the first embodiment of the present invention. First, the surface of a film transparent to a laser wavelength is charged by a method such as corona discharge (S).
1) Fine particles (transfer material) are electrostatically adsorbed on the entire surface or selectively (S2), and a laser beam is irradiated from the back surface (the surface on which no fine particles are adsorbed) of the film (S2).
3). The fine particles that have absorbed the laser beam are excited and rapidly increase in volume due to the ablation phenomenon (S4). Part of the energy is used to peel off the fine particles adsorbed on the film from the film, and the fine particles are peeled off from the film with a large amount of excess energy (S
5). The separated fine particles collide with the transfer material placed on the opposing surface in a high energy state (S6), and form (transfer) an image on the transfer material (S7).

FIG. 2 is a view showing an embodiment of the invention according to claim 2, wherein 1 is a film feed mechanism, and the transparent film 2 is continuously supplied by the film feed mechanism 1, and FIG.
The film 2 is charged by the charging mechanism 3. The charged particles 4 charged on the film 2 are fine particles (transfer material)
The fine particles (transfer material) 6 in the supply tank 5 are electrostatically adsorbed, and the adsorbed fine particles 6 are sent together with the film 2 to an irradiation unit of the laser beam 7. The fine particles 6 irradiated with the laser beam 7 are transferred onto the transfer object 8 placed on the opposite side. An image is formed by modulating the laser beam 7 and moving the transfer object 8 by the transfer object feeding mechanism 9.

FIG. 3 is a view showing an embodiment of the present invention according to claim 3. In the present invention, a fine particle collecting mechanism 10 is provided in a part of the apparatus according to claim 2, and the film 2 is made endless. It is designed to be supplied continuously. The laser beam from the laser 11 is processed by an optical system such as a mirror 12 and is irradiated from the inside of the endless film (sheet) 2.
Of the fine particles 6 adsorbed on the film 2, the fine particles not used for transfer are neutralized, or are scraped off by a mechanical scraping rod 13 and collected in the fine particle collecting mechanism 10. Thereby, the waste of the fine particles of the above-mentioned device is omitted,
In addition, the film 2 can be reused.

[0015] By using a laser beam in the ultraviolet region as the laser beam, the selection range of the transferable material is expanded, and many polymers can be used. In addition, in general, short wavelength light is higher in absorption efficiency for many polymers, and it is possible to implement an apparatus with reduced laser intensity. Further, by setting the intensity of the laser beam to be equal to or higher than the ablation threshold value of the chemical bond of the transfer particles, it is possible to reduce the thermal effect at the time of transfer, and it is possible to reduce pattern shift, pattern distortion and damage to the transparent film due to the thermal effect. Further, by performing fixing with a fixing device instead of laser ablation energy, it is possible to form an image with low laser intensity. Further, by scanning the laser light at a high speed with a polygon mirror, transfer at a higher speed than scanning the head can be performed. Furthermore, by integrating the laser device and the film, it is possible to reduce the size of the device, to reduce the cost of the device, and to easily replace all or a part of the integrated structure. Become. In addition, it becomes possible to use a conventional electrophotographic laser printer that transfers toner on paper using a material or a part of the apparatus as a printer. As a result, material development,
It is possible to reduce the cost of device development.

FIG. 4 is a view showing an embodiment of the invention described in claim 5. In this invention, a plurality of films 2 (2 ₁ , 2 ₂₎ used in the invention described in claim 2 or 3 are provided. ,
2 ₃ ) It is prepared so that different fine particles 6 are adsorbed to each. By scanning the laser beam 7 for each film or moving the sheet 2, a plurality of fine particle images can be formed. For example, by using two or more types of fine particles having different colors, An image can be formed with two or more types of colors. Desirably, by selectively transferring a transfer material of three colors of CMY (cyan, magenta, yellow) or four colors of CMYB (cyan, magenta, yellow, black), A color image can be formed.

FIG. 5 is a diagram showing an embodiment of the invention according to claim 6, wherein a plurality of fine particle forming apparatuses 5 (5 ₁ , 5 ₂ , 5) are provided in a part of the invention according to claims ₂ and 3. ₃ ), shutters 14 are provided for each of them, and the shutters 14 are controlled by the control device 15, whereby a pattern of a plurality of fine particles is formed on the film 2. By using this, an image can be formed without requiring complicated laser operation and film scanning. As described above, by forming two or more types of fine particles alternately and continuously on the film, it is possible to form an image with a plurality of fine particles such as a color using only a pair of sheets and a sheet feeding mechanism.

[0018]

According to the first aspect of the present invention, it is possible to form an image at high speed by transferring the electrostatically adsorbed particles adsorbed on the film from the film to the object by laser ablation. Further, the film material may be a film having an insulating property on a transparent surface, and does not require a function such as photoconductivity. Therefore, development is easy, and an insulating layer is formed on the insulating film itself or on the surface by a vapor deposition method or a sputtering method. A relatively inexpensive material such as a film formed by the above method can be selected. The transparent film can be selected from those having a transmittance that does not cause damage due to the laser wavelength, and a low-cost material can be selected. Many materials that can be electrostatically attracted to a film can be used as the transfer material.

According to the second aspect of the present invention, by utilizing the principle of the first aspect, a high-speed image forming apparatus can be manufactured. Further, a device having a small number of parts can be realized, the device can be easily reduced in size, and a large cost can be reduced by omitting a large-sized drum, a developing device, and a fixing device.

According to the third aspect of the present invention, a fine particle collecting mechanism for collecting fine particles as a transfer material is provided in the apparatus, and the adsorption and collection of the fine particles are repeatedly and continuously performed, so that the film can be reused or replaced. Enables continuous use,
Waste of fine particles and running cost can be reduced. Especially,
The use of ultraviolet laser light broadens the range of materials that can be transferred, and makes it possible to use many polymers. In addition, generally, in many polymers, short wavelength light has higher absorption efficiency, and therefore, it is possible to implement an apparatus with reduced laser intensity.

According to the fourth aspect of the present invention, by setting the intensity of the laser beam to be equal to or higher than the ablation threshold value of the chemical bond of the transfer particles, the heat effect at the time of transfer can be reduced. Damage can be reduced.
By performing fixing with a fixing device instead of laser ablation energy, it is possible to form an image with low laser intensity.

According to the fifth aspect of the present invention, it is possible to form an image with two or more types of colors. Desirably, three colors of CMY (cyan, magenta, yellow) or four colors of CMYB (cyan, magenta, yellow, black) are transferred. By selectively transferring the material, a color image can be formed.

According to the invention of claim 6, by forming two or more kinds of fine particles alternately and continuously on the film,
An image can be formed by a plurality of fine particles such as a color only by a pair of sheets and a sheet feeding mechanism.

Further, according to the present invention, in particular, by using a laser beam in the ultraviolet region, the selection range of transferable materials is widened, and many polymers can be used. In addition, generally, in many polymers, short wavelength light has higher absorption efficiency, and therefore, it is possible to implement an apparatus with reduced laser intensity. By performing fixing with a fixing device instead of laser ablation energy, it is possible to form an image with low laser intensity. By scanning the laser light with the polygon mirror at high speed, transfer at a higher speed than scanning the head becomes possible. In addition, by integrating the laser device and the film, the size of the device can be reduced, and the cost of the device can be reduced. Furthermore, it becomes easy to make all or part of the integral structure replaceable. In addition, it becomes possible to use a conventional electrophotographic laser printer that transfers toner on paper using a material or a part of the apparatus as a printer. This makes it possible to reduce the cost of material development and equipment development.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating an example of a laser image forming method according to claim 1;

FIG. 2 is a view showing one embodiment of a laser image forming apparatus according to claim 2;

FIG. 3 is a diagram showing one embodiment of the invention of claim 3;

FIG. 4 is a view showing one embodiment of the fine particle forming method according to claim 5;

FIG. 5 is a diagram showing an embodiment of the invention of claim 6;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Film feed mechanism, 2 ... Transparent film, 3 ... Charging mechanism, 4 ... Charged particle, 5 ... Fine particle supply tank, 6 ... Transfer fine particle, 7 ... Laser beam, 8 ... Transferred material, 9 ... Transferred material feed mechanism , 10 ... Particle collection mechanism, 11 ... Laser, 12 ...
Mirror, 13: fine particle scraping rod, 14: shutter, 1
5. Shutter control device.

Claims (6)

[Claims] 1. A method in which fine particles are electrostatically adsorbed on a film which is transparent to laser light and has an insulating property on the surface, and the fine particles electrostatically adsorbed on the film are scattered from the film by a laser ablation action. An image forming method, wherein the image is transferred onto a material to be transferred. 2. A laser light source capable of scanning, a film transparent to laser light and having an insulating property on a surface, a charging mechanism for the film, and fine particles for image formation. A laser, the image-forming fine particles being electrostatically adsorbed on the film, and the electrostatically adsorbed image-forming fine particles being transferred to a material to be transferred by laser ablation with laser light. Image forming device. 3. The laser image according to claim 2, further comprising a film continuous supply mechanism for continuously supplying the film, and a fine particle collecting mechanism for collecting the fine particles for image formation remaining on the film. Forming equipment. 4. The laser image forming apparatus according to claim 2, wherein the intensity of the laser light is equal to or higher than an ablation threshold of the image forming fine particles. 5. The laser image forming apparatus according to claim 2, comprising at least two kinds of different fine particles and a film obtained by adding the fine particles to the film. 6. The laser image forming apparatus according to claim 2, wherein two or more types of fine particles are alternately formed on the film.