JP4856587B2 - Ion generation control method, heat discharge type print head, and image forming apparatus including the same - Google Patents

Description

  The present invention relates to an ion generation control method for forming an electrostatic latent image and a visible image on an electrostatic latent image carrier and various recording media, a heat-discharge type print head, and an image forming apparatus including the same.

In recent years, as shown in (Patent Document 1) to (Patent Document 3), an ion irradiation method, which is an electrostatic latent image forming method different from the electrophotographic method, has been developed.
The electrophotographic method is a two-step process of uniform charging + exposure, and the electrostatic charge image is formed on the photoreceptor as an electrostatic latent image carrier by releasing the charge of the exposed part on the uniformly charged photoreceptor. On the other hand, in the ion irradiation method, in an atmosphere where ions can be generated (such as in the air), only selective charging (electrostatic latent image formation charging) by irradiation of ions generated by emission of electrons from the discharge electrode is performed. Since the formation of the electrostatic latent image can be completed on the electrostatic latent image bearing member (which is not necessarily a photosensitive member as long as it is an insulator), the electrostatic latent image forming method is simplified. .

  The ion irradiation methods of (Patent Document 1) to (Patent Document 3) are applied with a voltage (discharge control voltage) that generates a discharge by heating without generating a discharge only by being applied to the discharge electrode. It is a heating discharge method that controls the presence or absence of discharge to control the generation of ions by controlling the presence or absence of heating to the discharge electrode, and the voltage can be applied to the entire discharge electrode simultaneously, based on image information There is no need to individually control on / off of the voltage applied to the discharge electrode. As a result, it is possible to control the occurrence of discharge with a driver IC that supports low withstand voltage such as 5V drive used for controlling heating by a heating resistor or the like, and is the most excellent control method from the viewpoint of discharge control. It can be said that there is.

According to this ion irradiation type (heat discharge type) print head, an electrostatic development type recording medium that displays an image by the action of an electric charge (electrostatic latent image) applied to the surface, as represented by digital paper. On the other hand, since an electrostatic latent image can be directly formed by ion irradiation, it is an optimum image forming apparatus that can be considered at present for writing in a non-contact manner on an electrostatic development type recording medium.
In addition, as an application of an electrostatic latent image forming method using an ion irradiation method (Patent Document 3), it is formed on the surface of an electrostatic latent image carrier on which an electrostatic latent image is formed on the surface by ion irradiation. Based on the electrostatic latent image thus formed, a visible image is formed on the surface of the electrostatic latent image carrier by a visualization means using toner or ink, and the visible image is transferred to plain paper or OHP by a transfer means. An image forming apparatus for transferring to a print medium such as a sheet has also been proposed.
Japanese Patent No. 3725092 WO2005-056297 Japanese Patent No. 3936726

In each of (Patent Document 1) to (Patent Document 3), a voltage is directly applied to the discharge electrode, so that the discharge generation efficiency is excellent. However, since a high voltage is constantly applied to the discharge electrode, the damage to the discharge electrode is great, the amount of discharge is likely to change over time, and it has been desired to improve the durability and long life of the discharge electrode.
In addition, since the discharge electrode to which voltage is applied is selectively heated by a heating means to control the occurrence of discharge, when heating is performed using a heating resistor, the gap between the discharge electrode and the heating resistor must be ensured. It is necessary to insulate, and the insulating film is required to have high insulating properties, which takes a lot of manufacturing steps, and improvement in mass productivity and yield has been desired.

  The present invention meets the above-mentioned conventional demands, and it is not necessary to directly apply a voltage to the discharge electrode, and it is easy to control, and an ion generation control method that can improve the durability and long life of the discharge electrode. Even when heating the discharge electrode using a heating means such as a heating resistor, there is no need for high insulation between the heating means and the discharge electrode, and the process of forming the insulating film is simplified to improve the yield. It is possible to provide a heat discharge type print head that can be mass-produced and have a long service life. It is difficult for the discharge amount from the heat discharge type print head to change over time, and the image forming apparatus has excellent image quality reliability and stability. For the purpose of provision.

In order to solve the above-described problems, an ion generation control method, a heat-discharge type print head, and an image forming apparatus including the same according to the present invention have the following configurations.
The ion generation control method according to claim 1 of the present invention is an ion generation control method for controlling the generation of ions by controlling the temperature of the discharge electrode, and without applying a voltage directly to the discharge electrode. An electric field that generates a potential difference corresponding to a discharge control voltage between a counter electrode formed on, or in contact with, or close to a surface opposite to the recording surface of a recording medium disposed opposite to the discharge electrode by controlling the presence or absence of discharge and has a configuration for generating control of the ion by the presence or absence of heating to arranged the discharge electrode during.
This configuration has the following effects.
(1) A potential difference corresponding to a discharge control voltage between a discharge electrode and a counter electrode formed on, or in contact with, or close to a surface opposite to the recording surface of a recording medium disposed opposite to the discharge electrode Since the generation of ions is controlled by controlling the presence / absence of discharge depending on the presence / absence of heating of the discharge electrode disposed in the electric field that generates the voltage, it is not necessary to apply a voltage directly to the discharge electrode, By only selectively heating, a discharge can be generated from the discharge electrode, and a desired image can be formed by irradiating ions at an arbitrary position on the recording surface of the recording medium based on the image information.
(2) Since it is not necessary to apply a voltage directly to the discharge electrode, the durability and long life of the discharge electrode can be improved.

  Here, the discharge control voltage refers to a voltage range in which discharge from the discharge electrode does not occur only by the potential difference, but discharge occurs by heating the discharge electrode. The discharge electrode material, the type of recording medium, the surroundings It varies depending on the environment. When the discharge space formed by separating the discharge electrode and the recording medium is an atmosphere capable of generating ions such as air, the emitted electrons ionize oxygen and nitrogen, and these are ionized on the recording surface of the recording medium. Therefore, charges can be efficiently injected with a large amount of ions.

According to a second aspect of the present invention, there is provided a heating / discharging type print head comprising: an electric field forming portion; a discharge electrode disposed in an electric field formed by the electric field forming portion; and heating means for selectively heating the discharge electrode. And the electric field forming portion sets a potential difference corresponding to the electric field forming voltage between the electric field forming electrode arranged apart from the discharge electrode and the counter electrode and the electric field forming electrode. to has a potential difference setting unit, wherein the a discharge electrode disposed opposite the recording surface opposite the surface on formation or contact or close to the counter electrode disposed in the recording medium is, the the discharge electrodes, the A potential difference corresponding to a discharge control voltage is generated between them, and the generation of ions is controlled by controlling the presence or absence of discharge according to the presence or absence of heating of the discharge electrode by the heating means.
This configuration has the following effects.
(1) a counter electrode formed on, or in contact with, or close to a surface opposite to a recording surface of a recording medium disposed opposite to the discharge electrode by an electric field formed by the electric field forming unit; Since a potential difference corresponding to the discharge control voltage can be generated during this period, there is no need to apply a voltage directly to the discharge electrode. Generation control can be performed, and a desired image can be formed by irradiating ions to an arbitrary position on the recording surface of the recording medium based on the image information.
(2) There is no need to apply a voltage directly to the discharge electrode, and the discharge electrode is excellent in durability and long life.
(3) Since no voltage is directly applied to the discharge electrode, even when the discharge electrode is heated by heating means using a heating resistor, there is no need for high insulation between the heating resistor and the discharge electrode. The formation process can be simplified to improve the yield, and the mass productivity is excellent.
(4) The electric field forming unit includes an electric field forming electrode disposed apart from the discharge electrode, and a potential difference setting unit that sets a potential difference corresponding to the electric field forming voltage between the counter electrode and the electric field forming electrode. Thus, a potential difference corresponding to the discharge control voltage can be generated easily and reliably between the discharge electrode and the counter electrode without applying a voltage directly to the discharge electrode, and can be prepared for discharge. Only by selectively heating the electrode, the generation of discharge from the discharge electrode can be controlled, and the handleability is excellent.

Here, the electric field forming unit may be any one that can form an electric field that generates a potential difference corresponding to the discharge control voltage between the counter electrode and the discharge electrode. For example, an electrode or a coil that is disposed away from the discharge electrode to form an electric field is preferably used.
The discharge electrodes can be formed in a substantially strip shape or the like, and can be arranged in stripes according to the resolution of the recording medium. Note that the pitch of the discharge electrodes does not have to be the same as the resolution of the recording medium, and can be formed coarser than the resolution of the recording medium, and an image can be formed while gradually shifting the position according to the resolution of the recording medium. .
Any heating means for heating the discharge electrode may be used as long as it can selectively heat an arbitrary position (discharge generation portion) of the discharge electrode. The discharge electrode may be heated in close contact with the discharge electrode or separated from the discharge electrode. And may be heated.
As the heating means for heating by being in close contact with the discharge electrode, the same configuration as that of the thermal print head used in the conventional thermal facsimile can be suitably used. Specifically, the heat generation of the heating resistor is controlled by a driver IC electrically connected to the heating resistor. As this heating resistor, TaSiO ₂ , RuO ₂ or the like is preferably used.

  As a heating means for heating away from the discharge electrode, one having a light irradiation part such as a method of irradiating laser light or a method of irradiating infrared rays can be suitably used. As a light irradiating part for irradiating laser light, a laser irradiating part is combined with an optical scanning part such as a polygon mirror or a galvanometer mirror to scan only the laser light with respect to the discharge electrode. For example, a device that serially scans the laser irradiation unit itself is preferably used. Further, laser light or infrared light may be condensed by an optical fiber or a condensing lens and irradiated to the discharge electrode. In particular, when an optical fiber array in which a large number of optical fibers are arranged with high density and high accuracy is used, laser light and infrared rays can be selectively irradiated to the discharge generating portions of a plurality of discharge electrodes at the same time, enabling high-speed recording. Is possible. At this time, each optical fiber and the discharge electrode (discharge generation part) may be made to correspond one to one, and the exit tip of the optical fiber may be fixed to the discharge electrode. Alternatively, the discharge electrode can be formed by directly depositing chromium on the light exit surface of the light collecting portion such as the exit end of the optical fiber and gold plating.

The recording medium is not particularly limited as long as an electrostatic latent image is formed by the action of electric charge, and an electrostatic development recording medium such as digital paper or an electrostatic latent image carrier can be used.
When using an electrostatic development type recording medium, the display layer of the medium main body can selectively display liquid crystal type using a liquid crystal material having a shutter function such as transmissive nematic liquid crystal or smectic liquid crystal, or white or black. A material in which an image display material such as a twist ball method, an electrophoresis method, or a powder transfer method is enclosed is preferably used. In these recording media, the electrodes formed in a predetermined pattern on the upper and lower surfaces of the medium main body are irradiated with electrons and ions, and electric charges are injected so that the potential difference between the upper and lower electrodes is visible. A charge injection type recording medium for forming an image is also included.
These display layers combined with a color filter having the three primary colors (R, G, B) in the additive color mixing method and a reflective layer having the three primary colors (Y, M, C) in the subtractive color mixing method can perform color display. it can. Also, instead of combining color filters, color display is performed even when image display materials such as twist balls and fine particles colored in the three primary colors (Y, M, C) in the subtractive color mixing method are arranged for each display primary color. You can also. In addition, it is possible to use one that divides one medium body into a plurality of areas and displays different colors for each area.

The surface resistance of the recording surface of the recording medium is preferably one having a resistance value of 10 ⁹ Ω · cm to 10 ¹³ Ω · cm so that charges imparted by electrons and ions at the time of image formation disappear quickly. It is done. As the resistance value of the recording surface becomes smaller than 10 ⁹ Ω · cm, the electric charge placed on the recording surface of the recording medium tends to move on the surface, and the image tends to blur, and becomes larger than 10 ¹³ Ω · cm. Accordingly, the recording surface is easily charged, and the image tends to change due to the influence of static electricity or the like.

The counter electrode may be formed integrally with the medium main body on the surface (back surface) opposite to the recording surface of the recording medium, or may be a surface of a flat recording medium mounting portion or a conveyance roller provided in the image forming apparatus. And may be in contact with or close to the back surface of the medium body so as to face the discharge electrode.
The counter electrode is formed in a strip shape corresponding to each row or column of the display pixels of the medium body, or in a matrix corresponding to each pixel, in addition to being formed in a common solid shape over the entire surface of the medium body. By forming in a shape, selective grounding or voltage application can be performed. Particularly, those that can be selected in units of rows or columns are preferably used because selection control is easy.
When this counter electrode is divided and formed corresponding to the arrangement of display colors of the color filter or colored twist balls or fine particles, the counter electrode is selected in units of color of the display colors of the color display of the medium body. Therefore, the image information can be divided into color units to form an image, and color misregistration can be reliably prevented and a high-quality color image can be obtained.

As the electrostatic latent image carrier, various shapes such as a drum type, a belt type, and a flat plate type (sheet type) can be used. The material for the electrostatic latent image bearing member may be any material as long as the surface is charged by irradiation with electrons or ions, so it does not have to be a photosensitive member, but an insulator such as anodized or a film such as polyethylene terephthalate (PET). A synthetic resin, glass or the like can also be used. If the electrostatic latent image carrier is a photosensitive member, it can be neutralized by irradiating light, and if it is an insulator, it can be neutralized by an AC voltage. In addition, when the electrostatic latent image carrier is an insulator, the deterioration is less likely to occur compared to the photoreceptor, and the long life is excellent.
Based on the electrostatic latent image formed on the surface of the electrostatic latent image carrier, a visible image is formed on the electrostatic latent image carrier by the visualizing means, and the electrostatic latent image carrier itself is directly used as a recording medium. It can also be used as an image, or a visible image formed on an electrostatic latent image carrier can be transferred by a transfer means to form an image (visible image) on a printing medium such as plain paper or an OHP sheet. .

Here, the conventional heat discharge type print head (for example, Japanese Patent No. 3725092 and WO 2005/056297) applies a discharge control voltage directly to the discharge electrode and selectively heats the discharge electrode by a heating means. Controlling the occurrence of discharge. The discharge electrode of this conventional heat-discharge type print head is, for example, a comb shape in which one end portions of a plurality of discharge generating portions (individual discharge electrodes) are connected by a common electrode, and both end portions of the plurality of discharge generating portions are common electrodes or auxiliary common It was formed in a ladder shape connected by electrodes, a flat plate shape such as a rectangular shape or a square shape.
Heating discharge type print head according to claim 2 corresponds to that separating the common electrode and the discharge generating portion of the conventional discharge electrodes, the electric field forming electrode and the discharge electrode of claim 2, each conventional common electrode and discharge It can be regarded as a generation part.

The electric field forming voltage can be appropriately selected according to the distance between the discharge electrode and the electric field forming electrode so that a potential difference corresponding to the discharge control voltage is generated between the discharge electrode and the counter electrode.
Various waveforms can be selected as the waveform of the electric field forming voltage. Triangular waves, rectangular waves, trapezoidal waves, sine waves, etc. can be used alone or in combination, and a DC voltage or an AC voltage can be superimposed on them. it can. For example, when only an AC voltage is applied to the electric field forming electrode, positive and negative ions are generated along with the discharge from the discharge electrode. Therefore, to select only negative ions, a negative DC voltage is superimposed on the AC voltage, and to select only positive ions, an AC voltage superimposed with a positive DC voltage is applied to the electric field forming electrode. .

  The electric field forming electrode does not need to be opposed to the entire surface of the discharge electrode of the heat-discharge type print head, but may be at least partially opposed. Further, the electric field forming electrode may be fixed at one place, or the region where the electric field is formed may be moved while scanning the discharge electrode. When a method of irradiating light such as laser light or infrared light is used as the heating means, it is preferable to irradiate light from the surface side of the discharge electrode, but the discharge electrode forming substrate on which the discharge electrode is formed has translucency. In the case of being formed of glass or synthetic resin, the back surface of the discharge electrode can be irradiated with light from the discharge electrode forming substrate side and heated.

A third aspect of the present invention is the heating discharge type print head according to the second aspect, wherein the electric field formation is performed so that a potential difference corresponding to a discharge control voltage is generated between the discharge electrode and the counter electrode. An electric field forming voltage is distributed and applied to the electrode and the counter electrode.
With this configuration, in addition to the operation of the second aspect, the following operation is provided.
(1) The voltage applied to the electric field forming electrode and the counter electrode can be appropriately selected according to the type and characteristics of the recording medium.
Here, when a dedicated recording medium in which a counter electrode is integrally formed on the surface opposite to the recording surface or an electrostatic latent image carrier is used as the recording medium, a high-quality image can be obtained. That is, a counter electrode for forming an electric field is arranged on the surface (back surface) opposite to the recording surface of the recording medium between the electric field forming electrode and between the discharge electrode and the counter electrode of the heat discharge type print head. By applying grounding or voltage application to the counter electrode so that a potential difference corresponding to the discharge control voltage is generated, electrons and ions generated by the heat discharge type print head can surely reach the recording surfaces of various media. .
Even when the recording medium does not include a counter electrode, the counter electrode can be brought into contact with or close to the surface opposite to the recording surface of the recording medium by providing the counter electrode on the apparatus side. A high-quality image can be formed even on a recording medium that does not include the recording medium, the range of selection of the recording medium is wide, and the versatility is excellent.
The potential difference setting unit may apply all the voltage corresponding to the electric field forming voltage to the electric field forming electrode and ground the counter electrode, or correspond to the discharge control voltage between the discharge electrode and the counter electrode. A voltage corresponding to the electric field forming voltage may be appropriately distributed and applied to the electric field forming electrode and the counter electrode so that a potential difference is generated. The grounding and voltage application to the counter electrode may be performed constantly or selectively depending on the place or time.

According to a fourth aspect of the present invention, there is provided the heat discharge type print head according to the third aspect, wherein the potential difference setting unit is opposite to an electric field forming voltage applying unit that applies a voltage to the electric field forming electrode. A medium-side voltage selection unit that performs grounding or voltage application to the electrode.
With this configuration, in addition to the operation of the third aspect, the following operation is provided.
(1) The potential difference setting unit includes an electric field forming voltage applying unit that applies a voltage to the electric field forming electrode, and a medium side voltage selecting unit that performs grounding or voltage application to the counter electrode. Depending on the characteristics, the electric field forming voltage can be distributed and applied to the electric field forming electrode and the counter electrode, which is excellent in versatility and reliably corresponds to the discharge control voltage between the discharge electrode and the counter electrode. A potential difference can be generated, and a visible image or an electrostatic latent image can be formed by accurately irradiating a desired position on a recording surface with ions generated by a discharge, and the image has high quality. .

A fifth aspect of the present invention is the heat discharge type print head according to the third or fourth aspect, wherein the discharge electrode includes a power receiving unit formed at an end of the electric field forming electrode, and the electric field. A discharge generating portion formed at the end opposite to the forming electrode side, and the discharge electrode is covered with a coating film except for the power receiving portion and the discharge generating portion. is doing.
With this configuration, in addition to the operation of the third or fourth aspect, the following operation is provided.
(1) Since the discharge electrode has a power receiving portion formed at the end portion on the electric field forming electrode side, the electric field forming electrode and the power receiving portion can be opposed to each other, and the discharge electrode and the counter electrode can be opposed to each other. Therefore, a potential difference corresponding to the discharge control voltage can be generated efficiently, and the discharge generation reliability is excellent.
(2) Since the discharge electrode is covered with the coating film except for the power receiving section and the discharge generation section, it is possible to prevent the discharge from being generated from places other than the discharge generation section of the discharge electrode, and the discharge generation section is wasted. Therefore, the discharge can be generated intensively, the discharge generation efficiency is excellent, the discharge electrode can be protected, and the discharge electrode has excellent durability.

Here, the coating film is formed of an insulator, and a material such as glass, a synthetic resin such as aramid or polyimide, a ceramic such as SiO _2, or mica is preferably used. The coating film can be formed by screen printing, vapor deposition, sputtering, or the like.

A sixth aspect of the present invention is the heat discharge type print head according to any one of the second to fifth aspects, wherein the heating means includes a heating resistor that is insulated from the discharge electrode. It has a configuration.
With this configuration, in addition to the operation of any one of claims 2 to 5, the following operation is provided.
(1) Since the heating means includes a heating resistor that is insulated from the discharge electrode, a driver IC corresponding to a low withstand voltage such as 5 V drive can be used for the heating control, and the control of the discharge is possible. Easy and easy to handle.
(2) By insulating and closely contacting the discharge electrode and the heating resistor, the heat generated by the heating resistor can be efficiently transferred to the discharge electrode, and the discharge electrode corresponding to the generated heating resistor (discharge generation) Discharge) can be generated.

Here, as a material of the insulating film that insulates the discharge electrode from the heating resistor, it has insulation and heat resistance that can withstand the heating by the heating means, and also has heat transferability that can transfer the heat generated by the heating means to the discharge electrode. Those are preferably used. Specifically, synthetic resins such as glass, polyimide, aromatic polyamide, polyphenylene oxide, polybenzimidazole, polyphenylquinoxaline, polyarylate, polyetherimide, polyethersulfone, polyphenylene sulfide, polyetheretherketone, aramid, etc. Preferably used.
Since the heating resistor is as described in claim 2, the description is omitted.

A seventh aspect of the present invention is the heat discharge type print head according to any one of the second to fifth aspects, wherein the heating unit is disposed apart from the discharge electrode. It has the composition which is.
With this configuration, in addition to the operation of any one of claims 2 to 5, the following operation is provided.
(1) Since the heating means is a light irradiating part arranged away from the discharge electrode, an insulating film or the like for insulating the discharge electrode and the heating means is not provided between the discharge electrode and the heating means. Can be reliably insulated, the number of manufacturing steps can be reduced, and the mass productivity and the reliability of heating control can be improved.
(2) Since the discharge electrode and the heating means are arranged apart from each other, the separately manufactured products can be used in a simple combination, and when either the discharge electrode or the heating means is defective. In addition, it is possible to repair and replace only those that have malfunctioned, and it is excellent in maintainability and resource saving.
(3) Since the discharge electrode and the heating means are arranged apart from each other, the discharge electrode and the heating means do not come into contact with each other, so that the cooling time of the discharge electrode in the heating stopped state can be greatly shortened. In addition, it is possible to improve the responsiveness of the discharge stop with respect to the heating stop and switch the presence or absence of the discharge in a short time, thereby improving the image quality and the recording speed.

  Here, since the light irradiation part is as having demonstrated in Claim 2, description is abbreviate | omitted.

According to an eighth aspect of the present invention, there is provided an image forming apparatus comprising the heat discharge type print head according to any one of the second to seventh aspects.
This configuration has the following effects.
(1) By having a heat-discharge type print head, it is possible to impart electric charges to various media, and a visible image or an electrostatic latent image can be formed according to the type of the media.

Here, by providing a charging roller, a charging brush, or the like as a restoring device (initializing means), the surface of various media such as an electrostatic development type recording medium or an electrostatic latent image carrier inside the image forming apparatus can be obtained. It can be uniformly charged and initialized, and rewriting to various media can be repeated.
Instead of providing a restorer, unnecessary images can be erased by irradiating various media on which an image has been formed from a heat-discharge type print head with ions having a polarity opposite to that at the time of image formation.
In the case where the counter electrode is formed on the surface opposite to the recording surface of various media, the image forming apparatus may include a medium side voltage selection unit that performs grounding or voltage application to the counter electrode.
In addition, when the counter electrode is not formed on the surface opposite to the recording surface of the various media, the counter electrode is provided on the apparatus side with the counter electrode in contact with or close to the surface opposite to the recording surface of the various media. Grounding and voltage application can be performed by the voltage selection unit.

The image forming apparatus can form an image by fixing or relatively moving a heat discharge type print head and various media. Various media may be placed on a flat plate-like medium placement section, and the heat discharge type print head or the medium placement section may be moved horizontally, or various media may be transported by transport rollers. In particular, when the counter electrode is provided on the apparatus side, various media and the counter electrode can be brought into surface contact with each other by forming the counter electrode on the surface of the medium mounting portion, and the voltage applied to the counter electrode can be applied to the various media. By acting, the charge of electrons and ions can be reliably applied to the recording surface.
This image forming apparatus advertises a recording medium that is fixed or detachable as a display medium in addition to forming an image on an electrostatic development type recording medium that is carried and used as a medium instead of paper. It can also be used as an image display device such as a signboard for displaying images such as.

According to a ninth aspect of the present invention, in the image forming apparatus according to the eighth aspect of the invention, recording is performed on a recording medium in which a visible image appears due to the action of electric charges generated by the discharge from the heat-discharge type print head. It has the structure which performs.
With this configuration, in addition to the operation of the eighth aspect, the following operation is provided.
(1) Since a visible image can be formed in the recording medium in a non-contact manner by the discharge from the heat discharge type print head, the number of parts is small, and damage to the recording medium can be suppressed to the minimum necessary. Can be practical.

A tenth aspect of the present invention is the image forming apparatus according to the eighth aspect, wherein an electrostatic latent image is formed on the surface of the recording medium by the action of electric charges generated by the discharge from the heat-discharge type print head. An electrostatic latent image carrier, and a visualization means for forming a visible image on the recording medium based on the electrostatic latent image formed on the surface of the electrostatic latent image carrier. is doing.
With this configuration, in addition to the operation of the eighth aspect, the following operation is provided.
(1) Since the recording medium includes an electrostatic latent image carrier, an electrostatic latent image can be formed on the surface of the electrostatic latent image carrier by ion irradiation from a heat-discharge type print head. Based on the electrostatic latent image, a visible image can be formed on the surface of the recording medium by the visualization means.
(2) An electrostatic latent image can be formed on the surface of the electrostatic latent image carrier by irradiating ions from the heat-discharge type print head, so that an exposure optical system such as a polygon mirror is not required, and the number of parts is reduced. Less structure can be simplified.

Here, as the electrostatic latent image carrier, those similar to those described in claim 2 are preferably used. According to this image forming apparatus, a film-like synthetic resin such as polyethylene terephthalate (PET) is used. A high-quality image can be formed on an electrostatic latent image carrier formed of glass or glass.
As the developing means, a developing device for performing toner development is preferably used, but development may be performed by ink or other methods.

The invention according to an eleventh aspect is the image forming apparatus according to the eighth aspect, wherein the image forming apparatus is disposed so as to face the heat-discharge type print head, and is applied to the surface by the action of electric charges generated by the discharge from the heat-discharge type print head. An electrostatic latent image carrier on which an electrostatic latent image is formed is provided.
With this configuration, in addition to the operation of the eighth aspect, the following operation is provided.
(1) By having an electrostatic latent image carrier facing the heat discharge type print head, an electrostatic latent image can be formed on the surface of the electrostatic latent image carrier by ion irradiation from the heat discharge type print head. Because the electrostatic latent image can be used to electrostatically develop the recording medium to form a visible image, the heat-discharge type print head and the recording medium do not directly face each other, thereby preventing the heat-discharge type print head from being soiled. it can.

  Here, the electrostatic latent image carrier is the same as described in the first aspect, and thus the description thereof is omitted.

A twelfth aspect of the present invention is the image forming apparatus according to the eleventh aspect, wherein the electrostatic latent image carrier is formed on the basis of an electrostatic latent image formed on a surface of the electrostatic latent image carrier. The image forming apparatus has a configuration including a visualization unit that forms a visible image on the surface and a transfer unit that transfers the visible image to a recording medium.
With this configuration, in addition to the operation of the eleventh aspect, the following operation is provided.
(1) A visible image can be formed on the surface of the electrostatic latent image carrier based on the electrostatic latent image by the visualizing means, and the visible image is transferred to a recording medium by the transfer means for recording. Therefore, various printing media such as plain paper, OHP sheets, glossy paper, and the like can be used as recording media, and the versatility is excellent.

Here, as the electrostatic latent image carrier, the same ones as described above can be used. As the developing means, a developing device that performs toner development is preferably used in the same manner as described above, but development may be performed by ink or other methods. As a transfer means for transferring a visible image to a recording medium, a transfer fixing roller in which the surface of a metal roller such as aluminum is covered with a synthetic rubber such as silicone rubber is preferably used. When a pressure fixing type toner is used during toner development, a visible image can be transferred to a recording medium and fixed by being pressed by a transfer unit.
The image forming apparatus includes a cleaner that physically scrapes and cleans the toner remaining on the surface of the latent electrostatic image bearing member after transfer, and electrostatic writing before writing (ion irradiation) by the heat-discharge type print head. It is preferable to provide a static eliminator for neutralizing the surface of the latent image carrier. Thereby, the electrostatic latent image can be formed on the surface of the electrostatic latent image carrier in a stable state at all times, and the reliability is excellent. Further, when an insulator such as alumite is used as the electrostatic latent image carrier, scratching damage by the cleaner hardly occurs, and the long life is particularly excellent.

As described above, according to the ion generation control method, the heat discharge type print head, and the image forming apparatus of the present invention, the following advantageous effects can be obtained.
According to invention of Claim 1, it has the following effects.
(1) A potential difference corresponding to a discharge control voltage between a discharge electrode and a counter electrode formed on, or in contact with, or close to a surface opposite to the recording surface of a recording medium disposed opposite to the discharge electrode Since the generation of ions is controlled by controlling the presence / absence of discharge depending on the presence / absence of heating of the discharge electrode disposed in the electric field that generates the voltage, it is not necessary to apply a voltage directly to the discharge electrode, Discharge that can generate discharge from the discharge electrode by only selectively heating, and can form a desired image by irradiating ions on any position on the recording surface of the recording medium based on image information. It is possible to provide an ion generation control method having excellent controllability.

According to invention of Claim 2, it has the following effects.
(1) A potential difference corresponding to the discharge control voltage can be generated between the discharge electrode and the counter electrode by the electric field formed in the electric field forming unit without directly applying a voltage to the discharge electrode, and heating means The generation of ions can be controlled by controlling the presence / absence of discharge by the presence / absence of heating of the discharge electrode, and the desired image can be obtained by irradiating ions at any position on the recording surface of the recording medium based on the image information. It is possible to provide a heat discharge type print head excellent in durability and long life of the discharge electrode.
(2) The electric field forming voltage is applied between the electric field forming electrode and the counter electrode arranged apart from the discharge electrode, so that the discharge electrode and the counter electrode are not directly applied to the discharge electrode. The potential difference corresponding to the discharge control voltage can be easily and surely generated between the discharge electrode and the discharge electrode from the discharge electrode can be controlled simply by selectively heating the discharge electrode with the heating means. It is possible to provide a heat-discharge type print head excellent in handleability.

According to invention of Claim 3, in addition to the effect of Claim 2, it has the following effects.
(1) The voltage applied to the electric field forming electrode and the counter electrode can be appropriately selected according to the type and characteristics of the recording medium.

According to invention of Claim 4, in addition to the effect of Claim 3, it has the following effects.
(1) An electric field forming voltage applying unit that applies a voltage to the electric field forming electrode and a medium side voltage selecting unit that performs grounding or voltage application to the counter electrode, depending on the type and characteristics of the recording medium. The electric field forming voltage can be distributed and applied to the electrode and the counter electrode, which is excellent in versatility, and can generate a potential difference corresponding to the discharge control voltage between the discharge electrode and the counter electrode. To provide a heat discharge type print head excellent in image quality capable of forming a visible image or an electrostatic latent image by accurately irradiating a generated position to a desired position on a recording surface. Can do.

According to invention of Claim 5, in addition to the effect of Claim 3 or 4, it has the following effects.
(1) By covering the discharge electrode with a coating film except for the power receiving section and the discharge generation section, the discharge electrode can be protected, and discharge is generated from a location other than the discharge generation section of the discharge electrode. Therefore, it is possible to provide a heat discharge type print head excellent in durability of the discharge electrode capable of generating discharge intensively from the discharge generation portion without waste and efficiency in generating discharge.

According to invention of Claim 6, in addition to the effect of any one of Claims 2 thru | or 5, it has the following effects.
(1) By using a heating resistor insulated from the discharge electrode as a heating means, a driver IC corresponding to a low withstand voltage such as 5V drive can be used for heating control, and discharge control is easy. It is possible to provide a heat-discharge type print head excellent in handleability.

According to invention of Claim 7, in addition to the effect of any one of Claims 2 thru | or 5, it has the following effects.
(1) By using a light irradiating part arranged separately from the discharge electrode as a heating means, an insulating film or the like for insulating the discharge electrode and the heating means is not provided, so that there is no gap between the discharge electrode and the heating means. It is possible to provide a heat discharge type print head that can be reliably insulated, can be easily maintained, can reduce the number of manufacturing steps, and has excellent mass productivity and reliability of heating control.
(2) Since the discharge electrode and the heating means are spaced apart from each other, the discharge electrode and the heating means are not in contact with each other, and the cooling time of the discharge electrode in the heating stopped state can be greatly shortened. The present invention provides a heat discharge type print head that can improve the responsiveness of the discharge stop to the heat stop, can switch the presence or absence of discharge in a short time, enables high-speed recording, and has excellent discharge control and image quality reliability. be able to.

According to invention of Claim 8, in addition to the effect of any one of Claims 2 thru | or 7, it has the following effects.
(1) Use of a heat-discharge type print head that is easy to control discharge, can apply charges to various media, and can form a visible image or an electrostatic latent image depending on the type of the media. An image forming apparatus excellent in handleability can be provided.

According to invention of Claim 9, in addition to the effect of Claim 8, it has the following effects.
(1) By the discharge from the heat discharge type print head, a visible image can be formed in a non-contact manner inside the recording medium, the number of parts is small, and damage to the recording medium can be suppressed to the minimum necessary. An image forming apparatus that is practical and excellent in mass productivity and handling can be provided.

According to the invention described in claim 10, in addition to the effect of claim 8, the following effect is obtained.
(1) An electrostatic latent image can be formed on the surface of the electrostatic latent image carrier by irradiating ions from the heat-discharge-type print head, and on the basis of the electrostatic latent image, the visualization means A visible image can be formed on the surface, and the electrostatic latent image carrier can be used as a recording medium capable of forming a high-quality image.

According to the eleventh aspect of the invention, in addition to the effect of the eighth aspect, the following effect is obtained.
(1) An electrostatic latent image is formed on the surface of the electrostatic latent image carrier by ion irradiation from a heat-discharge type print head, and various recording media are electrostatically developed based on the electrostatic latent image to be visible. An image forming apparatus capable of forming an image, having a heat discharge type print head and a recording medium that are not directly opposed to each other, and capable of preventing the heat discharge type print head from being soiled and having excellent handleability and maintainability. Can be provided.

According to invention of Claim 12, in addition to the effect of Claim 11, it has the following effects.
(1) The visible image formed on the surface of the electrostatic latent image carrier based on the electrostatic latent image by the visualizing means can be transferred to the recording medium by the transfer means and recorded. In addition, it is possible to provide a versatile image forming apparatus that can use various printing media such as an OHP sheet and glossy paper as a recording medium.

An ion generation control method, a heat-discharge type print head and an image forming apparatus including the same according to the present invention will be described below with reference to the drawings.
(Embodiment 1)
FIG. 1A is a schematic cross-sectional view of an essential part of an image forming apparatus provided with the heat-discharge type print head according to the first embodiment, and FIG. 1B is a cross-sectional view taken along line AA in FIG. It is a schematic diagram.
In FIG. 1, reference numeral 1 denotes an image forming apparatus provided with the heating / discharging print head 10 of Embodiment 1 of the present invention, and 11 denotes an electric field forming voltage between a counter electrode 32 and an electric field forming electrode 13 described later. An electric field forming portion of the heating and discharging type print head 10 having a potential difference setting portion 14 for setting a potential difference to be formed; 13 is an electric field forming electrode of the electric field forming portion 11 formed on the substrate 12 and arranged separately from the discharge electrode 20; 15a is an electric field forming voltage application unit of the potential difference setting unit 14 for applying a voltage to the electric field forming electrode 13, 15b is a medium side voltage selection unit of the potential difference setting unit 14 for grounding to the counter electrode, and 16 is a heating means described later. A discharge electrode forming substrate of the heating / discharge type print head 10 on which the heating resistor 18a and the discharge electrode 20 are formed, and 18a is a heating formed in a strip shape at a position facing the electric field forming electrode 13 of the discharge electrode forming substrate 16. A stage heating resistor, 19 is a glass, polyimide, aromatic polyamide, polyphenylene oxide, polybenzimidazole, polyphenylquinoxaline, polyarylate, polyetherimide, polyethersulfone, polyphenylene sulfide, polyetheretherketone, aramid, etc. An insulating film 20 formed of a resin and covered with a heating resistor 18a on the discharge electrode forming substrate 16 is substantially strip-shaped by vapor deposition, sputtering, printing, plating, or the like of a metal such as gold, silver, copper, or aluminum. The discharge electrode 20a of the heating / discharge type print head 10 formed on the discharge electrode forming substrate 16 and insulated from the heating resistor 18a by the insulating film 19 on the discharge electrode forming substrate 16 is formed at the end of the discharge electrode 20 on the electric field forming electrode 13 side. A power receiving portion that is selectively heated by the heating resistor 18a, and 20b is a discharge. Discharge generating portion formed at the end opposite to the receiving portion 20a side of the pole 20, 21 is formed of glass, synthetic resin such as aramid or polyimide, ceramics such as SiO _2, an insulating material such as mica receiving A coating film covering the discharge electrode 20 except for the portion 20a and the discharge generating portion 20b, 30 is an electrostatic development type recording medium used in the image forming apparatus 1, 31 is a film-like synthetic resin such as PET, A medium substrate 32 of the recording medium 30 formed of glass or the like is formed in a strip shape of ITO or the like so as to correspond to each row of display pixels of the medium body 33 to be described later, and is opposed to the discharge generating portion 20b of the discharge electrode 20. The transparent counter electrode 33 of the recording medium 30 arranged in this way, 33 is the medium body of the recording medium 30 on which an electrostatic latent image is formed by the action of an electric charge and a visible image is formed inside, and 34 is the three primary colors in the additive color mixing method (R, G, B Is a color filter of the medium main body 33 arranged in a striped pattern, 35 is a liquid crystal method using a liquid crystal material having a shutter function such as a nematic liquid crystal or a smectic liquid crystal, or a twist ball method capable of selectively displaying white or black, The display layer of the medium body 33 in which an image display material such as an electrophoresis system or a powder movement system is enclosed, and s is a recording surface of the recording medium 30.

Next, details of the heating means of the heat-discharge type print head will be described.
FIG. 2 is a schematic plan view of the main part of the heating means of the heating and discharging type print head in the image forming apparatus of the first embodiment.
In FIG. 2, 18b is a driver IC of the heating means 17 that is electrically connected to the heating resistor 18a and controls the heat generation of the heating resistor 18a, 22a is a heating common electrode for energizing the heating resistor 18a, and 22b is It is a heating individual electrode for energizing the heating resistor 18a.

Next, details of the recording medium used in the image forming apparatus provided with the heat-discharge type print head in the first embodiment will be described.
FIG. 3 is a schematic plan view showing a color filter of a recording medium used in the image forming apparatus provided with the heat discharge type print head in the first embodiment, and FIG. 4 is provided with the heat discharge type print head in the first embodiment. FIG. 3 is a schematic plan view showing a counter electrode of a recording medium used in the image forming apparatus.
As shown in FIG. 3, the three primary colors (R, G, B) in the additive color mixing method are repeatedly arranged in a striped pattern on the color filter 34 as the display primary colors of the medium body 33.

  In FIG. 4, 32a is a color division electrode of the counter electrode 32 arranged corresponding to the three display primary colors (R, G, B) repeatedly arranged in a striped pattern on the color filter 34, and 32b is a color division electrode. An insulating film formed by coating 32a with a synthetic resin such as aramid or polyimide, and 32c is a connection opening formed in the insulating film 32b to connect the color separation electrodes 32a of the same color with a color selection electrode 32d described later. , 32d are color selection electrodes of the counter electrode 32 for connecting the color separation electrodes 32a of the same color and selecting the color separation electrode 32a in units of colors.

The medium main body 33 performs color display using transmitted light by combining the color filter 34 and the display layer 35. In the present embodiment, the color filter 34 includes the three primary colors (R, G, B) in the additive color mixing method, so that full color display can be performed. However, the display primary colors for color display may be two or more colors. A combination of colors can also be selected as appropriate. By dividing one pixel into a plurality of sub-pixels according to the number of display primary colors and arranging the display primary colors in a striped pattern in each sub-pixel, it is possible to cope with colorization.
The color filter 34 is not limited to the back surface of the display layer 35 and may be disposed on the upper surface (recording surface s) side of the display layer 35 as long as it can transmit light and perform color display. Moreover, you may arrange | position on the lower surface of transparent counter electrodes 32, such as ITO.

As the surface resistance of the recording surface s of the recording medium 30, a surface resistance of 10 ⁹ Ω · cm to 10 ¹³ Ω · cm is used so that charges imparted by electrons and ions at the time of image formation quickly disappear. did. As the resistance value of the surface of the recording surface s is less than 10 ⁹ Ω · cm, the charge placed on the recording surface s of the recording medium 30 is easily moved on the surface, they tend to image blurring, 10 ¹³ Omega · This is because it has been found that the recording surface s tends to be charged as it becomes larger than cm, and the image tends to change due to the influence of static electricity or the like.

The ion generation control method and the image forming method will be described based on the operation of the image forming apparatus including the heat discharge type print head configured as described above.
As shown in FIG. 1, first, in the electric field forming voltage application step of the electric field forming step in the electric potential difference setting step, the electric field forming voltage is applied to the electric field forming electrode 13 by the electric field forming voltage applying portion 15a of the potential difference setting portion 14. To do.
Subsequently, in the medium side voltage selection step of the electric field forming step in the potential difference setting step, the medium side voltage selection unit 15b of the potential difference setting unit 14 performs the color display unit colors (R, G, B) for the color display of the medium body 33. The counter electrode 32 is selected and grounded (here, the leftmost is selected).
Subsequently, in the discharge electrode heating step, the power receiving portion 20a (leftmost) of the discharge electrode 20 at the position corresponding to the pixel to display the selected color is selectively heated by the heating resistor 18a of the heating means 17. To do. At this time, since only the counter electrode 32 (leftmost) corresponding to the selected color in one pixel is grounded, the power receiving unit 20a (leftmost) of the discharge electrode 20 heated by the heating resistor 18a. ) Is injected from the electric field forming electrode 13. The injected charge is discharged from the discharge generating unit 20b (leftmost) connected to the power receiving unit 20a (leftmost) into which the charge has been injected, and is grounded on the counter electrode 32 (grounded on the recording surface s of the recording medium 30). Move towards the position corresponding to the (leftmost). Oxygen and nitrogen are ionized by the charge, and the recording surface s of the recording medium 30 is irradiated with ions, and the charge is injected to form an image.
Since no discharge occurs between the counter electrode 32 corresponding to another color that is not grounded and the discharge electrode 20, electrons generated by the discharge are present at the position of the sub-pixel on the leftmost counter electrode 32. The electrostatic latent image is formed and the image is displayed by the action of the charges of ions and ions, but the electrostatic latent image is not formed on the other counter electrode 32 and the image is not displayed. Further, no discharge is generated between the discharge generating portion 20b of the discharge electrode 20 that is not heated by the heating resistor 18a of the heating means 17 and the counter electrode 32 facing the discharge generating portion 20b.
The above operation is repeated for each display primary color to form a color image. When viewed from the surface opposite to the recording surface s of the recording medium 30, a color image formed based on the image information is displayed.

In the present embodiment, the discharge electrode heating step is performed as a subsequent step of the medium side voltage selection step. However, the medium side voltage selection step and the discharge electrode heating step may be performed simultaneously.
In the electric field forming voltage application step, the electric field forming voltage applying unit 15a applies all the voltage corresponding to the electric field forming voltage only to the electric field forming electrode 13, and in the medium side voltage selecting step, the medium side voltage selecting unit Instead of selectively grounding the counter electrode 32 at 15b, a potential difference corresponding to the discharge control voltage is generated between the discharge electrode 20 and the counter electrode 32 in the electric field forming voltage applying step and the medium side voltage selecting step. The electric field forming voltage may be distributed and applied to the electric field forming electrode 13 and the counter electrode 32. At this time, by selectively applying a voltage to the counter electrode 32 in the medium-side voltage selection step, it is not necessary to apply a useless voltage, and energy saving is excellent. Further, even if heating by the heating means 17 is mistakenly performed, no discharge is generated from the counter electrode 32 to which no voltage is applied, so that the reliability of discharge generation control is excellent.

The electric field forming voltage is appropriately determined according to the distance between the discharge electrode 20 and the electric field forming electrode 13 so that a potential difference corresponding to the discharge control voltage is generated between the discharge electrode 20 and the counter electrode 32. You can choose. The voltage applied to the electric field forming electrode 13 and the counter electrode 32 can be appropriately selected according to the type and characteristics of the recording medium 30.
When only an AC voltage is applied to the electric field forming electrode 13, positive and negative ions are generated. However, by superimposing a negative DC voltage, only negative ions can be selected, and discharge can be stabilized. In order to select only positive ions, a positive DC voltage may be superimposed on an AC voltage.

Note that the configuration of the electric field forming unit 11 is not limited to the present embodiment, and is capable of forming an electric field that generates a potential difference corresponding to the discharge control voltage between the discharge electrode 20 and the counter electrode 32. That's fine. For example, a coil or the like may be used instead of the electric field forming electrode 13.
In the present embodiment, the discharge electrode 20 is formed in a substantially strip shape and arranged in a striped pattern in accordance with the resolution of the recording medium 30 (pitch of the counter electrode 32), but the arrangement of the discharge electrode 20 is limited to this. It is not a thing. For example, if the discharge electrodes 20 are formed at a pitch that is coarser than the resolution of the recording medium 30 and an image is formed while gradually shifting the position according to the resolution of the recording medium 30, the pitch that is coarser than the resolution of the recording medium 30. A high-resolution image can be formed by the discharge electrode 20 formed in (1).

  Further, in this embodiment, the discharge electrode 20 is formed so that the pitch of the discharge electrode 20 on the power receiving unit 20a side and the pitch on the discharge generating unit 20b side are the same, but the pitch of the discharge electrode 20 on the power receiving unit 20a side is May be formed at a pitch that is coarser than the resolution of the recording medium 30, and the pitch on the discharge generating unit 20 b side may be the same as the resolution of the recording medium 30. As a result, the wiring pitch of the driver IC 18b for controlling the heat generation of the heat generating resistor 18a, the heat generating common electrode 22a for energizing the heat generating resistor 18a, and the heat generating individual electrode 22b can be expanded, and a short circuit or the like occurs. Difficult, mass production, and excellent operation reliability.

The electric field forming electrode 13 does not need to be opposed to all the power receiving portions 20a of the discharge electrode 20 at the same time, and may be opposed to a part thereof. In this case, if the electric field forming electrode 13 is scanned in the arrangement direction of the power receiving unit 20a, an electric field is formed at a desired position by the electric field forming electrode 13, and selective heating is performed by the heating means 17 to discharge the electrode. Electric charges can be injected into any of the 20 power receiving units 20a, and a discharge can be generated from the discharge generating unit 20b.
Further, in the present embodiment, the power receiving portion 20a facing the electric field forming electrode 13 is heated by the heating resistor 18a, but the heating position by the heating resistor 18a heats an arbitrary position in the longitudinal direction of the discharge electrode 20. can do. Therefore, the position of the discharge generation part 20b of the discharge electrode 20 may be heated.

  In the image forming apparatus 1 according to the present embodiment, the recording medium 30 is formed using the medium main body 33 that performs color display by combining the color filter 34 with the display layer 35 that can selectively display white or black. The medium is not limited to this. For example, without using the color filter 34, a medium body in which image display materials such as twist balls and fine particles colored in the three primary colors (Y, M, C) in the subtractive color mixing method are arranged for each display primary color may be used. A recording medium capable of color display can be formed. In addition to a full-color display, a recording medium that performs an arbitrary mono-color display can also be used.

In the present embodiment, the dedicated recording medium 30 in which the counter electrode 32 is integrally formed on the surface opposite to the recording surface s is used. However, even when the recording medium does not include the counter electrode 32, the image forming apparatus. By providing the counter electrode 32 on one side, the counter electrode 32 can be brought into contact with or close to the surface opposite to the recording surface s of the recording medium, and the recording medium without the counter electrode 32 has high quality. An image can be formed, the range of selection of the recording medium can be expanded, and versatility can be improved.
Further, the image forming apparatus 1 is provided with a charging roller, a charging brush, or the like as a restoring device (initializing unit), so that the electrostatic developing type recording medium 30 is uniformly charged inside the image forming apparatus 1. Initialization can be performed, and rewriting to the recording medium 30 can be repeated.
Instead of providing a restoring device, an unnecessary image can be erased by irradiating the recording medium 30 on which an image has been formed from the heat-discharge type print head 10 with ions having a polarity opposite to that at the time of image formation.

The image forming apparatus 1 can form an image by fixing or relatively moving the heat discharge type print head 10 and the recording medium 30. The recording medium 30 may be placed on a flat plate-like medium placing portion (not shown) so that the heat-discharge type print head 10 or the medium placing portion is moved horizontally. It may be conveyed. In particular, when the counter electrode 32 is provided on the image forming apparatus 1 side, the recording electrode 30 can be brought into surface contact with the discharge electrode 20 by forming the counter electrode 32 on the surface of the medium mounting portion. Thus, a potential difference corresponding to the discharge control voltage can be reliably generated between the counter electrode 32 and the charge of electrons or ions can be reliably applied to the recording surface s of the recording medium 30.
The recording medium 30 on which an image is formed can be carried and used as a medium instead of paper. However, if an image is displayed using the recording medium 30 fixed to the image forming apparatus 1 as a display medium, the image is displayed. The forming device 1 can be used as a rewritable image display device instead of an advertising billboard or the like.

The ion generation control method of Embodiment 1 has the following effects.
(1) Discharge control between the discharge electrode 20 and the counter electrode 32 formed on, or in contact with, or close to the surface opposite to the recording surface s of the recording medium 30 disposed opposite to the discharge electrode 20 Since the generation of ions is controlled by controlling the presence or absence of discharge by the presence or absence of heating to the discharge electrode 20 disposed in the electric field that generates a potential difference corresponding to the voltage, it is not necessary to apply a voltage directly to the discharge electrode 20. By simply heating the discharge electrode 20 selectively with the heating means 17, a discharge can be generated from the discharge electrode 20, and ions are irradiated to an arbitrary position on the recording surface s of the recording medium 30 based on the image information. Thus, a desired image can be formed.
(2) Since it is not necessary to apply a voltage directly to the discharge electrode 20, the durability and long life of the discharge electrode 20 can be improved.

The heating and discharging type print head according to the first embodiment has the following effects.
(1) A counter electrode 32 formed on, or in contact with, or close to, a surface opposite to the recording surface s of the recording medium 30 disposed opposite to the discharge electrode 20 by an electric field formed by the electric field forming unit 11. Since a potential difference corresponding to a discharge control voltage can be generated between the discharge electrode 20 and the discharge electrode 20, it is not necessary to apply a voltage directly to the discharge electrode 20, depending on whether the heating means 17 has heated the discharge electrode 20. The generation of ions can be controlled by controlling the presence or absence of discharge, and a desired image can be formed by irradiating ions at an arbitrary position on the recording surface s of the recording medium 30 based on the image information.
(2) It is not necessary to apply a voltage directly to the discharge electrode 20, and the durability and long life of the discharge electrode 20 are excellent.
(3) Since no voltage is directly applied to the discharge electrode 20, even when the discharge electrode 20 is heated by the heating means 17 using the heating resistor 18a, high insulation is provided between the heating resistor 18a and the discharge electrode 20. The process for forming the insulating film 19 can be simplified and the yield can be improved, and the mass productivity is excellent.
(4) The electric field forming unit 11 sets a potential difference corresponding to the electric field forming voltage between the electric field forming electrode 13 spaced apart from the discharge electrode 20 and the counter electrode 32 and the electric field forming electrode 13. By having the potential difference setting unit 14, a potential difference corresponding to the discharge control voltage can be generated easily and reliably between the discharge electrode 20 and the counter electrode 32 without applying a voltage directly to the discharge electrode 20. It is possible to control the generation of the discharge from the discharge electrode 20 only by selectively heating the discharge electrode 20 with the heating means 17, and the handleability is excellent.
(5) The potential difference setting unit 14 includes the electric field forming voltage applying unit 15 a that applies a voltage to the electric field forming electrode 13 and the medium side voltage selecting unit 15 b that performs grounding to the counter electrode 32. And the counter electrode 32 can reliably generate a potential difference corresponding to the discharge control voltage, and accurately irradiate a desired position on the recording surface with ions generated along with the discharge so that a visible image or electrostatic image can be generated. A latent image can be formed, and the image quality is excellent.
(6) Since the discharge electrode 20 has the power receiving unit 20a formed at the end portion on the electric field forming electrode 13 side, the electric field forming electrode 13 and the power receiving unit 20a can be made to face each other close to each other. And the counter electrode 32 can efficiently generate a potential difference corresponding to the discharge control voltage, and the discharge reliability is excellent.
(7) Since the coating film 21 is provided on the discharge electrode 20 except for the power receiving unit 20a and the discharge generation unit 20b, it is possible to prevent discharge from being generated from a location other than the discharge generation unit 20b of the discharge electrode 20. In addition, discharge can be intensively generated from the discharge generating portion 20b, and the discharge generation efficiency can be excellent, the discharge electrode 20 can be protected, and the durability of the discharge electrode 20 is excellent.
(8) Since the heating means 17 is a heating resistor that is insulated from the discharge electrode 20, a driver IC corresponding to a low withstand voltage such as 5V drive can be used for the heating control, and the discharge control can be performed. Easy and easy to handle.
(9) By insulating and closely adhering the discharge electrode 20 and the heating resistor 18a, the heat generated by the heating resistor 18a can be efficiently transferred to the discharge electrode 20, corresponding to the heat generating resistor 18a that has generated heat. Discharge can be generated from the discharge electrode 20 (discharge generation part 20b).

The image forming apparatus according to Embodiment 1 has the following effects.
(1) By having the heat-discharge type print head 10, it is possible to apply a charge to the recording medium 30 and form a visible image.
(2) Since a visible image can be formed in the recording medium 30 in a non-contact manner by the discharge from the heat-discharge type print head 10, the number of parts is small and the damage to the recording medium 30 is minimized. It can be pressed and is highly practical.

(Embodiment 2)
FIG. 5A is a schematic cross-sectional view of an essential part of the image forming apparatus provided with the heat-discharge type print head according to the second embodiment, and FIG. 5B is a cross-sectional view taken along line BB in FIG. It is a schematic diagram. In addition, the same code | symbol is attached | subjected to the thing similar to Embodiment 1, and description is abbreviate | omitted.
In FIG. 5, the image forming apparatus 1a according to the second embodiment is different from the first embodiment in that recording is performed based on the electrostatic latent image formed on the surface of the recording medium 30a provided with the electrostatic latent image carrier 33a. The point is that a visualization means 25 for forming a visible image on the medium 30a is provided.
As the developing means 25, a developing device that performs toner development is preferably used, but development may be performed by ink or other methods.

The heating discharge type print head 10a used in the image forming apparatus 1a of the second embodiment is different from that of the first embodiment in that the electric field forming electrode 13 of the electric field forming portion 11a is not opposed to the power receiving portion 20a of the discharge electrode 20. The discharge electrode 20 is arranged in the series direction, the electric field forming electrode 13 is applied with a voltage by the electric field forming voltage applying unit 15a, and one end of the voltage applying common electrode portion is a voltage applying common electrode portion. 13a, the other end is formed in a comb shape having a divided electrode portion 13b divided corresponding to the power receiving portion 20a of the discharge electrode 20, and in the medium side voltage selecting portion 15c of the potential difference setting portion 14, A heating unit having a light irradiation part disposed away from the discharge electrode 13 instead of the heating unit 17 using the heating resistor 18a and a point where a voltage is applied to the counter electrode 32 of the recording medium 30a. It is that it includes a 7a.
As the heating unit 17a, a combination of a light irradiation unit and a polygon mirror or a galvanometer mirror, or a unit that serially scans the light irradiation unit is preferably used.

Further, the recording medium 30a used in the image forming apparatus 1a of the second embodiment is different from that of the first embodiment in that an electrostatic latent image carrier 33a is provided instead of the electrostatic developing medium body 33. And the counter electrode 32 is formed in a common solid shape over the entire surface of the electrostatic latent image carrier 33a.
The material of the electrostatic latent image carrier 33a may be any material as long as the surface is charged by irradiation with electrons or ions. Therefore, it is not necessary to be a photoconductor, and an insulator such as anodized or polyethylene terephthalate (PET). A film-like synthetic resin or glass can also be used.

The ion generation control method and the image forming method will be described based on the operation of the image forming apparatus including the heat discharge type print head configured as described above.
As shown in FIG. 5, first, in the electric field forming step in the potential difference setting step, an electric field is applied to the electric field forming electrode 13 and the counter electrode 32 by the electric field forming voltage applying unit 15a and the medium side voltage selecting unit 15c of the potential difference setting unit. A forming voltage is distributed and applied.
Subsequently, in the discharge electrode heating step, the power receiving unit 20a (leftmost) of the discharge electrode 20 at the position corresponding to the pixel on which an image is to be displayed is selectively heated by the heating unit 17a. At this time, a voltage is applied to the common electrode 32 common to the entire surface of the recording medium 30a. However, since the power receiving portion 20a (leftmost) of the discharge electrode 20 is selectively heated by the heating means 17a, the heating is performed. Electric charges are injected from the electric field forming electrode 13 only into the power receiving portion 20a (leftmost) of the discharge electrode 20 heated by the means 17a. The injected charge is discharged from the discharge generating unit 20b (leftmost) connected to the power receiving unit 20a (leftmost) into which the charge has been injected, and the discharge generated by discharging the charge on the recording surface s of the recording medium 30a. The shortest distance is moved toward the position facing the portion 20b. Oxygen and nitrogen are ionized by the charges, and the recording surface s of the recording medium 30a is irradiated with ions, and the charges are injected to form an electrostatic latent image.
No discharge is generated between the discharge generating portion 20b of the discharge electrode 20 that is not heated by the heating means 17a and the counter electrode 32 facing the discharge generating portion 20b.
The above operation is repeated for each pixel of the recording medium 30a to form an electrostatic latent image on the entire recording surface s of the recording medium 30a.
When the electrostatic latent image forming step is completed, the voltage application by the medium side voltage selection unit 15c of the potential difference setting unit 14 is stopped, and the electrostatic image formed on the surface of the electrostatic latent image carrier 33a by the visualization unit 25 is stopped. A developing process for forming a visible image on the recording medium 30a based on the latent image is performed.

In the present embodiment, in the electric field forming step, the electric field forming voltage applying unit 15a of the potential difference setting unit 14 applies a voltage to the electric field forming electrode 13, and the medium side voltage selecting unit 15c is opposed to the electric field forming voltage. The medium side voltage selection step for applying a voltage to the electrode 32 is performed simultaneously, and the discharge electrode heating step is performed as the subsequent step. However, only the electric field forming voltage application step of the electric field forming step is performed first, and the medium side voltage is thereafter processed. You may perform a selection process and a discharge electrode heating process simultaneously.
Further, instead of distributing and applying the electric field forming voltage to the electric field forming electrode 13 and the counter electrode 32, in the electric field forming voltage applying step, the electric field forming voltage applying unit 15a applies an electric field in the electric field forming voltage application step, as in the first embodiment. All the voltages corresponding to the forming voltage may be applied only to the electric field forming electrode 13, and the counter electrode 32 may be grounded by the medium side voltage selecting unit 15b in the medium side voltage selecting step.

  In the present embodiment, light is irradiated from the surface side of the discharge electrode 20 by the heating means 17a. However, the discharge electrode forming substrate 16 is formed of translucent glass, synthetic resin, or the like, and from the discharge electrode forming substrate 16 side. It is also possible to heat the back surface of the discharge electrode 20 by irradiating light. In addition, when heating the back surface of the discharge electrode 20 from the discharge electrode formation board | substrate 16 side by the heating means 17a, a heating position is not limited to the position of the power receiving part 20a, The arbitrary positions of the discharge electrode 20 can be heated. .

  In the present embodiment, on the basis of the electrostatic latent image formed on the surface of the electrostatic latent image carrier 33a, the visualizing means 25 forms a visible image on the recording surface s of the recording medium 30a and records it as it is. Although the case where the image forming apparatus includes the electrostatic latent image carrier 33a has been described, the visible image formed on the electrostatic latent image carrier 33a is further provided by providing a transfer unit. An image (visible image) can also be formed on a printing medium such as plain paper or an OHP sheet by transferring with a transfer means. As the transfer means, a transfer fixing roller in which the surface of a metal roller such as aluminum is covered with a synthetic rubber such as silicone rubber is preferably used. When a pressure fixing type toner is used during toner development, a visible image can be transferred to a recording medium and fixed by being pressed by a transfer unit.

The ion generation control method of Embodiment 2 has the following effects.
(1) Discharge control between the discharge electrode 20 and the counter electrode 32 formed on, or in contact with, or close to the surface opposite to the recording surface s of the recording medium 30a disposed to face the discharge electrode 20 Since the generation of ions is controlled by controlling the presence or absence of discharge by the presence or absence of heating to the discharge electrode 20 disposed in the electric field that generates a potential difference corresponding to the voltage, it is not necessary to apply a voltage directly to the discharge electrode 20. By simply heating the discharge electrode 20 selectively with the heating means 17a, a discharge can be generated from the discharge electrode 20, and ions are irradiated to an arbitrary position on the recording surface s of the recording medium 30a based on image information. Thus, a desired image can be formed.
(2) Since it is not necessary to apply a voltage directly to the discharge electrode 20, the durability and long life of the discharge electrode 20 can be improved.

The heating and discharging type print head according to the second embodiment has the following effects.
(1) A counter electrode 32 formed on, in contact with, or in close proximity to the surface opposite to the recording surface s of the recording medium 30a disposed opposite to the discharge electrode 20 by an electric field formed by the electric field forming portion 11a. Since a potential difference corresponding to the discharge control voltage can be generated between the discharge electrode 20 and the discharge electrode 20, it is not necessary to apply a voltage directly to the discharge electrode 20, and the presence or absence of heating of the discharge electrode 20 by the heating means 17a. The generation of ions can be controlled by controlling the presence or absence of discharge, and a desired image can be formed by irradiating ions at an arbitrary position on the recording surface s of the recording medium 30a based on the image information.
(2) It is not necessary to apply a voltage directly to the discharge electrode 20, and the durability and long life of the discharge electrode 20 are excellent.
(3) The electric field forming unit 11 a sets a potential difference corresponding to the electric field forming voltage between the electric field forming electrode 13 that is disposed apart from the discharge electrode 20, and the counter electrode 32 and the electric field forming electrode 13. By having the potential difference setting unit 14, a potential difference corresponding to the discharge control voltage can be generated easily and reliably between the discharge electrode 20 and the counter electrode 32 without applying a voltage directly to the discharge electrode 20. It is possible to control the generation of discharge from the discharge electrode 20 only by selectively heating the discharge electrode 20 with the heating means 17a, and the handleability is excellent.
(4) Since the potential difference setting unit 14 includes an electric field forming voltage applying unit 15a that applies a voltage to the electric field forming electrode 13 and a medium side voltage selecting unit 15c that applies a voltage to the counter electrode 32, a recording medium Depending on the type and characteristics of 30a, the electric field forming voltage can be distributed and applied to the electric field forming electrode 13 and the counter electrode 32, which is excellent in versatility and between the discharge electrode 20 and the counter electrode 32. A potential difference equivalent to the discharge control voltage can be generated reliably, and a visible image or an electrostatic latent image can be formed by accurately irradiating a desired position on the recording surface with ions generated by the discharge. Excellent image quality.
(5) Since the discharge electrode 20 has the power receiving portion 20a formed at the end portion on the electric field forming electrode 13 side, the electric field forming electrode 13 and the power receiving portion 20a can be made to face each other close to each other. And the counter electrode 32 can efficiently generate a potential difference corresponding to the discharge control voltage, and the discharge reliability is excellent.
(6) Since the coating film 21 is covered on the discharge electrode 20 except for the power receiving unit 20a and the discharge generation unit 20b, it is possible to prevent discharge from being generated from a location other than the discharge generation unit 20b of the discharge electrode 20. In addition, discharge can be intensively generated from the discharge generating portion 20b, and the discharge generation efficiency can be excellent, the discharge electrode 20 can be protected, and the durability of the discharge electrode 20 is excellent.
(7) Since the heating means 17a is a light irradiation part arranged separately from the discharge electrode 20, the insulating film for insulating the discharge electrode 20 and the heating means 17a is not provided, and the discharge electrode 20 It is possible to reliably insulate from the heating means 17a, reduce the number of manufacturing steps, and improve the mass productivity and the reliability of the heating control.
(8) Since the discharge electrode 20 and the heating means 17a are spaced apart from each other, they can be used in a simple combination, and there is a problem with either the discharge electrode 20 or the heating means 17a. When a problem occurs, only the defective part can be repaired or replaced, and the maintenance and resource saving are excellent.
(9) Since the discharge electrode 20 and the heating means 17a are arranged apart from each other, the discharge electrode 20 and the heating means 17a do not come into contact with each other, so that the cooling time of the discharge electrode 20 in the heating stopped state is greatly increased. Therefore, it is possible to improve the responsiveness of the discharge stop with respect to the heating stop and switch the presence or absence of the discharge in a short time, thereby improving the image quality and the recording speed.

The image forming apparatus according to Embodiment 2 has the following effects.
(1) By having the heat-discharge type print head 10a, an electric charge can be applied to the recording medium 30a and an electrostatic latent image can be formed.
(2) Since the recording medium 30a includes the electrostatic latent image carrier 33a, an electrostatic latent image can be formed on the surface of the electrostatic latent image carrier 33a by ion irradiation from the heat-discharge type print head 10a. On the basis of the electrostatic latent image, the visualizing means 25 can form a visible image on the surface of the recording medium 30a.
(3) Since an electrostatic latent image can be formed on the surface of the electrostatic latent image carrier 33a by irradiation of ions from the heat-discharge type print head 10a, an exposure optical system such as a polygon mirror is not required, and the component The number of points is small and the structure can be simplified.

  The present invention provides an ion generation control method that does not require voltage to be directly applied to the discharge electrode, is easy to control, can improve the durability and long life of the discharge electrode, and heats a heating resistor. Even when the discharge electrode is heated using a means, there is no need for high insulation between the heating means and the discharge electrode, the process of forming an insulating film can be simplified and the yield can be improved, and mass productivity and long life can be achieved. Provide a heat-discharge-type print head with excellent properties, and provide an image-forming device that is less likely to change with time in the amount of discharge from the heat-discharge-type print head and has excellent image quality reliability. Therefore, a high quality image can be formed.

(A) Schematic cross-sectional view of the main part of the image forming apparatus provided with the heat-discharge type print head of Embodiment 1 (b) Schematic cross-sectional view taken along line AA in FIG. Schematic plan view of the main part of the heating means of the heat-discharge type print head in the image forming apparatus according to the first embodiment. Schematic plan view showing a color filter of a recording medium used in an image forming apparatus provided with a heat-discharge type print head in the first embodiment Schematic plan view showing a counter electrode of a recording medium used in an image forming apparatus provided with a heat-discharge type print head in Embodiment 1. (A) Schematic cross-sectional view of relevant parts of an image forming apparatus provided with the heat-discharge type print head according to the second embodiment (b) Schematic cross-sectional view taken along line BB in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a Image forming apparatus 10, 10a Heating discharge type print head 11, 11a Electric field formation part 12 Substrate 13 Electric field formation electrode 14 Potential difference setting part 15a Electric field formation voltage application part 15b, 15c Medium side voltage selection part 16 Discharge electrode formation Substrate 17, 17a Heating means 18a Heating resistor 18b Driver IC
DESCRIPTION OF SYMBOLS 19 Insulating film 20 Discharge electrode 20a Power receiving part 20b Discharge generating part 21 Cover film 22a Common electrode for heat generation 22b Individual electrode for heat generation 25 Visualization means 30, 30a Recording medium 31 Medium substrate 32 Counter electrode 32a Color division electrode 32b Insulating film 32c Connection opening 32d Color selection electrode 33 Medium body 33a Electrostatic latent image carrier 34 Color filter 35 Display layer s Recording surface

Claims (12)

An ion generation control method for controlling the generation of ions by controlling the temperature of a discharge electrode, wherein a surface opposite to a recording surface of a recording medium disposed opposite to the discharge electrode without directly applying a voltage to the discharge electrode discharge and a counter electrode formation or contact or close to being disposed, by the presence or absence of heating to the discharge electrodes and the discharge electrodes and the potential difference corresponding to the discharge control voltage is placed in an electric field to be generated between the Control of ion generation by controlling the presence or absence of ions, an ion generation control method. An electric field forming part; a discharge electrode disposed in an electric field formed by the electric field forming part; and a heating means for selectively heating the discharge electrode, wherein the electric field forming part is separated from the discharge electrode. And a potential difference setting unit that sets a potential difference corresponding to a voltage for forming an electric field between the counter electrode and the electrode for forming an electric field, and arranged to face the discharge electrode. Generating a potential difference corresponding to a discharge control voltage between a counter electrode formed on, or in contact with, or close to a recording surface of a recording medium to be recorded, and the discharge electrode; A heating and discharging type print head, wherein the generation of ions is controlled by controlling the presence or absence of discharge according to the presence or absence of heating of the discharge electrode. 3. The electric field forming voltage is distributed and applied to the electric field forming electrode and the counter electrode so that a potential difference corresponding to a discharge control voltage is generated between the discharge electrode and the counter electrode. The heat-discharge type print head described in 1. The potential difference setting unit includes an electric field forming voltage applying unit that applies a voltage to the electric field forming electrode, and a medium side voltage selecting unit that performs grounding or voltage application to the counter electrode. The heat discharge type print head according to claim 3. The discharge electrode has a power receiving portion formed at an end portion on the electric field forming electrode side, and a discharge generating portion formed at an end portion opposite to the electric field forming electrode side, and the power receiving portion 5. The heating discharge type print head according to claim 3, wherein a coating film is provided on the discharge electrode except for the discharge generating portion. 6. The heat discharge type print head according to claim 2, wherein the heating means includes a heating resistor insulated from the discharge electrode. The heating / discharging type print head according to any one of claims 2 to 5, wherein the heating means is a light irradiating portion disposed apart from the discharge electrode. An image forming apparatus comprising the heat-discharge type print head according to any one of claims 2 to 7.   9. The image forming apparatus according to claim 8, wherein recording is performed on a recording medium in which a visible image appears due to an effect of electric charges generated by discharge from the heating and discharging type print head. The recording medium includes an electrostatic latent image carrier on which an electrostatic latent image is formed on the surface by the action of electric charges generated by discharge from the heating / discharge type print head, and is formed on the surface of the electrostatic latent image carrier. The image forming apparatus according to claim 8, further comprising: a visualization unit that forms a visible image on the recording medium based on the electrostatic latent image. An electrostatic latent image carrier that is disposed to face the heating / discharge type print head and forms an electrostatic latent image on the surface by the action of electric charges generated by the discharge from the heating / discharge type print head is provided. The image forming apparatus according to claim 8. Visualizing means for forming a visible image on the surface of the electrostatic latent image carrier based on the electrostatic latent image formed on the surface of the electrostatic latent image carrier, and using the visible image as a recording medium The image forming apparatus according to claim 11, further comprising a transfer unit that transfers the image.

Images