JPH04212863A - Screen for controlling recording for electric field attraction recording device and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide an electric field attraction type recording device which has high recording quality and reliability by a method wherein wettability of a sateen for controlling recording is selected to an optimum value, in a screen for controlling recording used for the electric field attraction type recording device. CONSTITUTION:An electric field attraction type recording device is a device which attracts and adheres conductive ink 1 to a recording medium 3 from an ink reservoir. A screen 2c for controlling recording having a number of small holes 6 is disposed between the ink 1 and the recording medium 3, and the ink l can pass through the holes 6 to the recording medium 3 by exerting an electrostatic attraction force, on the ink 1. In the electric field attraction type recording device, an inner wall 9 of the hole 6 of the screen 2c for controlling recording has repellency to ink and a surface 10 positioned facing the ink 1 of the screen 2c for controlling recording has ink affinity.

Description

Detailed Description of the Invention [0001] The present invention relates to an electric field attraction type recording device applicable to printers, facsimile machines, etc., and particularly relates to a recording control screen used in an electric field attraction type recording device. and its manufacturing method. As non-impact printers, recording methods and apparatuses thereof, such as inkjet type thermal transfer type and electrophotographic type, have been put into practical use. However, these recording methods and devices are
Although it has many advantages, it also has advantages and disadvantages when considering recording speed, reliability, running cost, ease of colorization, etc. For example, in order to increase the recording speed, it is necessary to arrange the ink transfer elements of the print head in a line arrangement. However, in the inkjet recording method and apparatus, it is difficult to arrange the ink ejection nozzles in a line. Therefore, although some devices with improved nozzle arrangement etc. have been proposed, they have not yet been put into practical use. [0005] Furthermore, the thermal transfer recording method and its apparatus have the problem of high running costs because the ink sheet is a consumable item that cannot be used repeatedly. [0006] Therefore, as a recording method to solve these problems, an electric field attraction type recording apparatus has been proposed. The electric field attraction type recording device has a simple structure;
Suitable for downsizing equipment. It also has advantages such as high reliability and low running costs. The present invention was accomplished in order to further improve the recording quality and reliability of the electric field attraction type recording device. [0009] FIG. 5 is a diagram illustrating the outline of an electric field attraction type recording device and its operation, in which (a) is a diagram explaining the outline of the configuration, and (b), (c), and (d) are diagrams explaining the outline of the configuration. FIG. 6 is an enlarged view of the portion marked with a broken circle in FIG. That is, the ink 1 is attracted by electrostatic force and passed through the recording control screen 2 to the recording medium (recording paper).
This is a recording device that attaches ink to paper. (1) General structure The structure is such that a recording control screen 2 having a large number of fine holes 6 is interposed between the ink 1 and the recording medium 3. That is, one surface of the recording control screen 2 is in contact with the ink 1, and the other surface is in contact with the recording medium 3. The recording control screen 2 is made of a mesh sheet, a porous film, or the like, and its material is a material with low wettability to the ink 1 (an ink-repellent material). [0013] Therefore, due to the interfacial tension of the ink 1 with respect to the recording control screen 2, the ink 1 does not pass through the holes 6 and come out in a natural state. On the other hand, in order to apply electrostatic force to the ink 1,
An electrode 4 is provided inside the ink 1, and a counter electrode 5 is provided with the recording control screen 2 and the recording medium 3 in between. Then, a voltage is applied between the ink electrode 4 and the counter electrode 5 by the power source E and the switch SW. That is, when the switch SW is closed, an attractive force due to electrostatic force acts between the ink 1 and the counter electrode 5.
The ink 1 passes through the holes 6 of the recording control screen 2, and is attracted and attached to the recording medium 3. Incidentally, as the ink 1, a water-based ink having conductivity is used. Therefore, a water-repellent member is used for the recording control screen 2. However, oil-based inks can also be used as long as they have conductivity. (2) Operation Figures 5(b), (c), and (d) are diagrams sequentially explaining the operation. In this figure, in order to make the explanation easier to understand, the operation of one hole 6 of the recording control screen 2 is shown, and only the recording control screen 2 is shown in a sectional view. That is, recording is performed by operating in the following order 1) to 3). 1) Natural state (steady state) (Figure (b)) Since the wettability of the ink 1 to the recording control screen 2 is low, the ink 1 cannot enter the holes 6 due to the interfacial tension of the ink 1. Therefore, the position of meniscus 7 of ink 1 is
It is held near the inner edge of the recording control screen. 2) Application of electric field (voltage) (Figure (c)) By applying a voltage between the ink electrode 4 and the counter electrode 5, an attractive force due to electrostatic force acts on the ink 1, and the ink 1 It passes through the hole 6 and adheres to the recording medium 3. 3) Release of electric field (voltage) application, that is, natural state ((d)
Figure) Ink 1 attached to recording medium 3 is ink dot 8
, the ink dot 8 penetrates into the recording medium 3,
A recording is made. [0021] The most important element in an electric field suction type recording device is the wettability of the recording control screen 2 with respect to the ink 1. That is, this is because passage/non-passage of the ink 1 is controlled via the holes 6 of the recording control screen 2. [0022] The inventors have found that stainless steel, nylon, Tetron, and even Teflon are suitable materials for obtaining low wettability (ink permeability) with Ink 1, for example, when Ink 1 is a water-based ink. , has proposed the use of this material as a material for the recording control screen 2 and has filed a patent application. However, when the above-mentioned material is used as it is, due to the water repellency (ink repellency) of the material, the ink 1 may leak from the holes 6 and unnecessary ink may adhere to the recording medium 3. Or, even though a voltage is applied, the ink 1 does not pass through the holes 6 and the ink does not adhere to the recording medium 3, making it impossible to expect improvement in recording quality and lowering reliability. There is. FIG. 6 is a diagram illustrating the relationship between the recording control screen and its water repellency. (a), (b), and (c) are diagrams illustrating cases where the water repellency is insufficient, and (d) is a diagram illustrating the case where the water repellency is insufficient. It is a figure explaining the case where it has sufficient aqueous content. Note that, like FIG. 5, only the recording control screen is shown in a cross-sectional view. (1) Insufficient Water Repellency Stainless steel, nylon, and Tetron have insufficient water repellency as materials for the recording control screen 2a, and the following problems occur. In other words, immediately after the start of use, as shown in FIG.
As shown in FIG. 2, the meniscus 7 of the ink 1 is held near the inner end of the recording control screen 2a. However, the suction of the ink 1 to the recording medium 3
By repeating the adhesion (recording), the inner wall 9 of the hole 6 becomes wet with the ink 1, and the meniscus 7 of the ink 1 enters the recording medium 3 side as shown in (b) and (c), causing a slight The ink 1 adheres to the recording medium 3 due to impact or fluctuations in applied voltage, resulting in erroneous recording. In other words, the recording margin when the ink 1 adheres to the recording medium 3 is reduced, and the reliability of the recording apparatus is also lowered. In particular, this problem is caused by the ink 1 used.
The lower the surface tension, the more pronounced this becomes. (2) When water repellency is sufficient Teflon has excellent water repellency and is the most suitable material for the recording control screen 2a. However, the following problems may occur. That is, as shown in (d), since the surface 10 of the recording control screen 2b in contact with the ink also has water repellency, the ink 1 floats up from the holes 6.
Ink 1 cannot be supplied to the printer. Therefore, even if a voltage is applied to the ink 1, the ink 1 will come out from the hole 6 and the recording medium 3.
may not adhere to the surface. In other words, recording omissions may occur. In particular, such problems become more pronounced as the surface tension of the ink 1 used increases. Furthermore, since it is difficult to make Teflon into fibers, recording control screens are manufactured by making holes in it, but it is difficult to make holes as small as several tens of micrometers in diameter. In other words, it is difficult to create a screen. The technical problem of the present invention is to solve the above-mentioned problems in the recording control screen of an electric field suction type recording device, and to provide optimal ink permeability and ink affinity for each surface of the screen. The object of the present invention is to realize an electric field attraction type recording device with high recording quality and reliability by realizing a recording control screen that selectively has the following. [Means for Solving the Problems] FIG. 1 is a diagram illustrating the basic principle of the present invention. The present invention is characterized in that the inner wall 9 of the hole 6 of the recording control screen 2c is ink-repellent, and the surface 10 in contact with ink is ink-philic. (1) Basic configuration of the recording control screen A recording control screen 2c having a large number of fine holes 6 is provided between the ink 1 and the recording medium 3. By applying an electrostatic attraction force to the ink 1, the ink 1 is drawn into the hole 6.
In an electric field suction type recording device that can reach the recording medium 3 by passing through the recording control screen 2c, the inner wall 9 of the hole 6 of the recording control screen 2c is ink-repellent, and the recording control screen 2c
This is a recording control screen for an electric field suction type recording device in which a surface 10 in contact with ink 1 is ink-philic. (2) Method for manufacturing a recording control screen The recording control screen of the above (1) is produced by applying a permeable ink treatment agent to a screen having a large number of fine holes 6, and then bringing the screen into contact with at least the ink. It can be manufactured by lapping the surface and removing the ink treatment agent. It is more effective to further apply or transfer an ink-friendly treatment agent to the surface from which the live ink treatment agent has been removed. [0038] The recording control screen can also be formed from at least two layers of an ink-repellent material and an ink-philic material. In this case, the configuration is such that the ink-philic material contacts the ink 1 and the ink-repellent material faces the recording medium 3. [Function] (1) Basic configuration of the recording control screen Since the inner wall 9 of the hole 6 of the recording control screen 2c is ink-permeable,
The inner wall 9 of the hole 6 becomes wet and the meniscus 7 of the ink 1 does not enter the recording medium 3 side. Furthermore, since the surface 10 of the recording control screen 2c in contact with the ink 1 is ink-philic, the ink 1
will no longer rise up from the hole 6. Therefore, ink 1 is mistakenly printed on recording medium 3.
This eliminates the possibility that the film will stick to the surface and stain it, or that it will not stick to the surface and cause recording omissions. (2) Method for manufacturing a screen for recording control According to this manufacturing method, even if the material does not have sufficient ink repellency, it is possible to impart ink repellency to the inner walls 9 of the holes of the screen. can. [0043] Also, the surface 10 where the screen comes into contact with the ink
can provide good ink affinity. [0044] Therefore, it is possible to eliminate the disadvantages of Teflon, which is difficult to form into fibers and form fine holes, and to manufacture a recording control screen having only the advantages of Teflon. Further, a recording control screen having a two-layer structure in which an ink-repellent material and an ink-philic material are stacked has the same effect as described in (1) above. [Example] Next, how the recording control screen of the present invention can be practically implemented will be explained using an example. In this example, water-based ink was used. (1) Water repellent treatment and hydrophilic treatment FIG. 2 is a flowchart illustrating the manufacturing procedure of the recording control screen. FIG. 3 is a diagram illustrating the state of water-repellent treatment and hydrophilic treatment of the screen, and (a) to (d) are cross-sectional views of the screen in each manufacturing process. By the way, in the same figure, water repellent treatment agent 1 is applied to screen 2A.
This is an example in which 1 and a hydrophilic treatment agent 12 are dipped or applied. [0049] The steps will be explained below in order. ■ Degrease and clean screens such as mesh sheets and porous films with fine pores to remove oil and fat components that inhibit the adhesion of water repellent and hydrophilic treatment agents. For example, ultrasonic cleaning with acetone. (2) Dry the screen so that no residue of cleaning agent remains. (See Figure 3(a)) 00
51] ■ Immerse the screen in a water repellent treatment agent. Although there are methods such as spraying or transferring a water repellent treatment agent, considering that the inner walls of the fine pores of the screen are to be treated, a method using immersion is suitable because it has excellent uniformity. (See FIG. 3(b)) ■ Dry the screen by blowing air. Note that air drying also serves to prevent the holes in the screen from being clogged with the water repellent treatment agent. (2) If it is desired to selectively perform water repellent treatment only on the inner walls of the holes in the screen, the surface is polished (lapping) except for the inner walls to remove unnecessary water repellent treatment agents. (Figure 3(c)
) Reference) [0054] ■Clean the screen and remove unnecessary water repellent treatment agent that has been scraped off by polishing and adhered to it. (2) Dry the screen so that no residue of cleaning agent remains. (2) If it is desired to perform hydrophilic treatment on the surface from which the water repellent treatment agent has been removed by polishing, the hydrophilic treatment agent is applied or transferred. (See FIG. 3(d)) ② The hydrophilic treatment agent is dried to complete the recording control screen. (2) Results of Treatment A high-performance fluororesin-based agent is suitable as the water repellent treatment agent. For example, Sumiflunone (manufactured by Sumitomo Chemical) can be used. Furthermore, if the screen is made of a material with high heat resistance such as stainless steel, a method of baking fluororesin is also possible. Incidentally, by coating the Tetoron screen with a fluororesin, the contact angle of the ink increased from 90° to 130°, and water repellency was significantly improved. On the other hand, various surfactants, polycarbonate resins, etc. can be used as the hydrophilic treatment agent. Incidentally, by coating the Tetoron screen with a fluorine-based surfactant, the contact angle of the ink was increased from 90° to 15°, and the hydrophilicity was significantly improved. Furthermore, as a result of using the recording control screen of this example in a recording apparatus, good recording (printing) results could be obtained without unnecessary ink adhesion or recording omissions. (3) Recording control screen with two-layer structure FIG. 4 is a sectional view illustrating a recording control screen formed by laminating a water-repellent sheet and a hydrophilic sheet. That is, it is used so that the hydrophilic sheet 14 is located on the ink 1 side and the water repellent sheet 13 is located on the recording medium side. In this embodiment, the ink 1 penetrates to the boundary between the hydrophilic sheet 14 and the water-repellent sheet 13, and a meniscus 7 is formed. As for the material, polyethylene resin or the like can be used for the water-repellent sheet, and polycarbonate resin or the like can be used for the hydrophilic sheet. [0068] The recording control screen of this embodiment is as follows:
Although sheets with holes 6B formed in advance may be bonded together, it is difficult to align the holes 6B, so forming the holes 6B after bonding is easier to manufacture. Incidentally, the hole 6B can be formed by punching or electrical discharge machining. [0069] As described above, according to the recording control screen of the present invention, the ink meniscus can be stably maintained, so that a wide and stable recording margin can be maintained. . As a result, an electric field attraction type recording device with high recording quality and high reliability can be realized.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the basic principle of the present invention.

FIG. 2 is a flowchart illustrating a manufacturing procedure of a recording control screen.

FIG. 3 is a diagram illustrating the state of water-repellent treatment and hydrophilic treatment of the screen, and (a) to (d) are cross-sectional views of the screen in each manufacturing process.

FIG. 4 is a sectional view illustrating a recording control screen formed by laminating a water-repellent sheet and a hydrophilic sheet.

FIG. 5 is a diagram illustrating an overview of the electric field attraction type recording device and its operation, where (a) is a diagram explaining the outline of the configuration, and (b) (
c) (d) is an enlarged view of the part marked with a dotted circle in (a), and is a diagram sequentially explaining the operation. Note that only the recording control screen is shown in cross-sectional view.

[Figure 6] Diagrams explaining the relationship between recording control screens and their water repellency; (a), (b), and (c) are diagrams illustrating cases where water repellency is insufficient, and (d) is a diagram illustrating cases where water repellency is sufficient. FIG. Note that only the recording control screen is shown in cross-sectional view.

[Explanation of symbols]

1 Ink 2, 2a, 2b
, 2c Recording control screen 2A
screen 3
Recording medium (recording paper) 4
Ink electrode 5
Counter electrode 6, 6A, 6B hole

Claims (4)

[Claims] 1. An apparatus that performs recording by attracting and adhering conductive ink (1) from an ink reservoir to a recording medium (3) using electrostatic force, the ink (1) and the recording medium (3) being attached to the recording medium (3). ) A recording control screen (2c) with a large number of fine holes (6) is provided between the ink (1) and the ink (1) by applying electrostatic attraction to the ink (1). 1) passes through the hole (6) and the recording medium (
3) In an electric field suction type recording device that reaches , the inner wall (9) of the hole (6) of the recording control screen (2c) is made ink-permeable, and the ink (1) of the recording control screen (2c) and A recording control screen for an electric field attraction type recording device, characterized in that a contacting surface (10) is ink-philic. 2. A live ink treating agent is applied to a screen having a large number of fine holes (6), and then at least the surface (10) of the screen in contact with the ink (1) is subjected to a lapping process to remove the live ink treating agent. A method for manufacturing a recording control screen, characterized by: removing. 3. After the wrapping process according to claim 2 is completed, the screen contacts the ink (1) (1).
0) A method for manufacturing a recording control screen, comprising: applying an ink-friendly treatment agent to the screen. 4. The layer of ink-philic material is an ink (1).
Claim 1 characterized in that it is formed of at least two layers of the ink-philic material and the ink-repellent material so that the ink-repellent material layer is in contact with the recording medium (3) and faces the recording medium (3).
A recording control screen for the electric field attraction type recording device described above.