JP2013212616A - Decoloring inkjet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inkjet recording device provided with a means for studying concrete requirements for extracting features of decoloring ink and giving the meaning of using it with a background that inkjet recording devices using decoloring inks are proposed, but the simple use of such an ink never provides a workable product.SOLUTION: An inkjet recording device has a decoloring step prior to a printing step by decoloring ink. The inkjet recording device is installed with both general ink and decoloring ink to be separately used, and similarly has the decoloring step prior to the printing step. When printing with the decoloring ink, "a mark expressing printing with decoloring ink" is additionally printed on printed matter.

Description

  The present invention relates to an ink jet recording apparatus using a decolorizable ink.

  An ink jet recording apparatus using a decolorizable ink has been proposed. Patent Documents 1, 2, 3 and the like. These proposals, however, describe in detail the inks used, but only describe the use of a decolorizable ink in an ink jet recording apparatus. Such a basic recording apparatus is hard to say that it can be actually used, and has not been put into practical use. It is necessary to study specific requirements for making the device usable in practice by taking advantage of the characteristics of the color erasable ink, and to develop a new technical device for realizing them.

JP-A-4-198282 JP 2001-172535 A JP 2009-227956

  Among the proposals of the ink jet recording apparatus using the decolorizable ink, the ink performance described in Patent Document 3: Japanese Patent Application Laid-Open No. 2009-227956 is particularly excellent. Similar ink has been put to practical use in ballpoint pens and the like. The erasing temperature is designed to be, for example, 60 ° C., and the recorded matter by this ink can be completely erased by the frictional heat generated when it is rubbed with a shaved solid at the other end of the ballpoint pen made of elastomer or the like. . Many people find it useful. The use of this ink in an ink jet recording apparatus is a proposal of Patent Document 3.

  Now, consider what it means to “use decoloring ink for?”. Ink-jet recording apparatuses that are widely used at present print using durable, non-erasable ink (referred to as permanent ink in contrast to decolorizable ink). Sometimes “temporary use” such as disposable memos and test prints, printing information for private use only, or printing for work when it is difficult to read on the display, is one of the printing purposes. . In these cases, printing is performed on the back side of paper that has been used for printing purposes, and paper is saved. However, printed paper that has been used up to the back side can no longer be used. It will be discarded. There is no choice but to use new paper. When paper stock is low, you may want to use used paper that can only be discarded. Here, there is a meaning of printing with decoloring ink. Print for “temporary use”. When you are finished using it, turn it off. And again use it as printing paper. This is the way in which decolorizable ink is used. It is printed on the premise of erasing. There is no purpose of printing with decolorizable ink other than the purpose of “erasing and reusing”.

  In lines 44 to 48 of Paragraph No. 0033 of Patent Document 3, “The printed matter has a black temperature-sensitive color-change image visually recognized at room temperature (25 ° C.), and is heated to 57 ° C. or higher to produce a temperature-sensitive color-change image. Was erased and returned to the state before use (recording paper on which nothing was printed) at room temperature (25 ° C.). Again, by setting the recording paper in the ink jet recording apparatus and performing printing, a temperature-sensitive discolored image can be formed to obtain a printed matter, and the recording paper can be used repeatedly. This suggests that printing information is erased and recording paper is used repeatedly. The same description can be seen in other places, but no specific device is suggested. Of course, it has been explained that the color is erased when the temperature is raised from the characteristics of the ink. As the color erasing means, a method of rubbing with a friction tool of a writing instrument and a method of heating with a dryer are introduced. However, one or two words can be erased by rubbing with a writing tool friction tool. For example, printing over a large area printed on A4 paper can be erased by rubbing with such a writing tool friction tool. Is not easy. However, it is not realistic to bring a dryer or other heating equipment such as an iron each time. You can put it on a stove and put it on fire like a laver, but it is dangerous.

  In line 12 to line 18 of paragraph No. 0020 of Patent Document 3, “When obtaining the ink cartridge set or the ink jet recording apparatus set, the writing instrument's complete discoloration temperature t4 of the microcapsule pigment contained in the ink for ink jet is described. By reducing the complete decolorization temperature t4 of the microcapsule pigment contained in the ink, only the handwriting formed by the writing tool can be erased by frictional heat. In this case, the temperature difference between the complete decoloration temperature t4 of the microcapsule pigment contained in the ink-jet ink and the complete decoloration temperature t4 of the microcapsule pigment contained in the ink of the writing instrument is 10 ° C or higher, preferably 15 ° C or higher. More preferably, it is 20 ° C. or higher ”. Here, a patent proposal has been made for a set of a writing instrument containing an erasable ink and an ink jet recording apparatus. Even if an additional entry is made on an ink jet recording paper printed with an erasable ink with a writing instrument, only that part is a writing instrument. It can be erased by rubbing with a friction tool. It does not seem to mean that the recorded contents printed by the ink jet are erased by the friction tool of the writing instrument.

Problem 1 It can be said that it is “practical” only when the printed matter printed with the erasable ink can be used and the printed content can be erased and used again as a blank paper. It is essential for an ink jet recording apparatus using a decolorable ink to have a certain erasing function (or decoloring function) for erasing the “entire surface” and a printing function. Of course, there may be a plan to have a full-color automatic decoloring device separate from the recording device. However, apart from that, it is cumbersome to actually use, and it takes up a lot of space and costs to get the device. It should be a device that has both functions by itself and can be used easily and flexibly. Its creation is the first issue.

Problem 2 Even if the above problem is solved, a device that only has a printing / erasing function using decoloring ink has a certain purpose, but it is still too special and has the motive to be bothered to purchase. I can't say that. However, such a device has not yet been put into practical use. The value of the decolorizable ink is born only when there is a function of mainly using printing using permanent ink and performing printing with the decolorable ink as necessary for the above-mentioned purpose. Of course, it is not necessary to say that the present invention also has means for solving the first problem (a device for realizing an automatic full erasure function).

Problem 3 It is inconvenient to accidentally use a document printed with decoloring ink as an official document, and it must be avoided. A device to prevent this misuse is necessary for an ink jet recording apparatus using a decolorizable ink.

Problem 4 It is necessary to avoid applying heat to the ink somewhere in the printing process. The selection of the component for that is important.

  A first problem solving means for achieving the above object of the present invention includes a step of printing using at least a decolorizable ink in an ink jet recording apparatus, and printing using a decolorable ink before the printing step. And an erasing step for erasing all the printed contents of the printed matter.

  The second problem solving means has at least a normal permanent type ink and a color erasable ink, and has a color erasing process for erasing all the printed contents of the printed matter printed using the color erasable ink. An ink jet recording apparatus having a function of selectively using both inks as necessary.

  A third problem solving means is an ink jet recording apparatus characterized in that, in the first and second problem solving means, a heating device is used in the decoloring step.

  The fourth problem-solving means is the ink jet type recording apparatus according to the first, second, and third problem-solving means. An ink jet recording apparatus that performs additional printing.

  According to a fifth problem-solving means, in the first and second problem-solving means, at least the print head that prints with a decolorizable ink is a non-heating print head such as a piezo element. It is a recording device.

  (Effect 1) In this proposal, a decoloring process is arranged before the printing process, and the “erasable” printed matter that has been “automatically” used by “one device” can be completely returned to a blank sheet “over the entire surface”. it can. The refreshed white paper can be continuously printed, and can be stored as printing paper at the next printing opportunity. You can save energy for erasing by badge processing a lot of printed material you want to erase. Only with this automatic color erasing function, the color erasable ink jet recording apparatus became practical.

  Prints printed with decolorizable ink cannot be used as official documents. Because it disappears so perfectly. A printer equipped only with decolorizable ink is valuable as a printing machine for “temporary use” if it has the automatic decoloring function described above, but there are few opportunities for use by itself. The second aspect of the present invention also has a normal ink jet printing function using permanent type ink, which is a dual mode printer or a hybrid printer. And these can be easily used properly. This made the decolorizable ink printing more practical. (Effect 2)

  (Effect 3) Performing the color erasing process with a “heating device” is a method that matches the color erasing characteristics of the color erasing ink.

  The fourth problem-solving means is the ink jet recording apparatus according to the first, second, and third problem-solving means. It is characterized by additional printing, and this effect is “error prevention”. Again, the performance of this decolorizable ink is great. The print quality of printed matter is no different from permanent ink. That's why it's a problem. You can tell if the print is faint, the density is low, or it disappears in 1-2 minutes. But it is not. The print quality is so high that it cannot be distinguished. It must be avoided to misuse the printed matter of decolorizable ink as an official document. This can be achieved by additionally printing on the printed material a “mark that clearly indicates that printing was performed with the color-erasable ink”. The addition of this function is an essential requirement for a recording apparatus equipped with a decolorizable ink. “Prevention of misuse” or “prevention of mistake” is (effect 4).

  The decolorizable ink is decolored by raising the temperature. One of the ink jet recording methods is a method in which minute elements are heated instantaneously, ink is boiled, bubbles are formed, and ink droplets are ejected from minute holes using the force of rapid expansion and contraction. There is. When a decolorizable ink is applied to this recording method, the ink loses its color due to the heating process, and the color density as a whole changes. It is difficult to use as ink for printing. Therefore, in this erasable ink jet recording system, at least the print head is preferably a non-heating print head such as a piezo element. By not applying heat to the color-erasable ink in the recording process (printing process), stable color-erasable ink recording can be performed. (Effect 5).

It is a cross-sectional view of a decoloring ink jet recording apparatus having a decoloring step. FIG. 2 is a plan view of a hybrid ink jet recording apparatus that includes a color erasing process and can perform printing with a color erasable ink and a permanent ink. FIG. 2 is a cross-sectional view of a hybrid ink jet recording apparatus that includes a decoloring process and can perform decoloring ink printing and permanent ink printing independently. FIG. 4 is a plan view of the ink jet recording apparatus of FIG. 3. It is a cross-sectional view of a “heating device” that embodies the decoloring process. It is an example of the printed matter which printed "the mark which specifies that it printed with the decoloring ink."

  FIG. 1 shows a cross-sectional view of a decolorizable ink jet recording apparatus 1 having a decoloring process. In response to the printing instruction, printing paper (for example) is fed out from the paper cassette 2 in which it is stored, and advances along a paper path 4 indicated by a dotted line as indicated by an arrow. After passing through the erasing process 6 and reaching the printing process 5, the erasable ink is ejected from the print head, information is printed on the printing paper, and discharged to the paper discharge tray 3. Except for using a decolorizable ink and having a decoloring process, it is a mechanism of an ordinary inkjet printer.

  After using the printing paper, the used printing paper is loaded into the paper cassette 2 or loaded into a manual feed mechanism (not shown). In response to the next printing instruction, the printing paper is sent out and the erasing process 6 is reached. A pair of feed rollers 8 is provided before the color erasing step 6 and a pair of feed rollers 9 is provided after the color erasing step 6 to ensure stable paper conveyance. When the printing paper passes through the decoloring step 6, the previous printed content is erased. Then, in the next printing step 5, new information is printed.

  A second exemplary embodiment is shown in the plan view of FIG. In the printing process 5, an ink cartridge 5-1 containing normal inkjet ink (permanent ink) and a cartridge 5-2 containing decolorizable ink are mounted on the carriages 5-11 and 5-21, respectively. Has been. Printing is performed by scanning these carriages so as to be orthogonal to the paper path 4 as indicated by arrows 7. When performing printing with permanent ink, the two carriages are separated, and only the carriage 5-11 on which the permanent ink cartridge 5-1 is mounted is scanned and printed. This is a separation / contact scanning method for preventing a decoloring ink cartridge that is not frequently used from moving unnecessarily. At the time of printing with the erasing ink used occasionally, the erasing ink cartridge is scanned by combining both carriages for printing. However, one of the design options is to integrate the two, always scan together, and use either ink according to the user's instructions.

  In the printer driver, a check box for “erasable ink printing” is provided in the “printing basic setting screen” that appears first when a printing instruction is issued. The mark is removed by default. If this box is checked by the user's intention, the “erasable ink printing mode” is set. Basically, a “decolorable ink printing mark”, which will be described later, is printed out of the margin of the print area, for example, the header portion. The additional printing of the “decolorable ink printing mark” can also be removed on the “printing option screen”.

  Another embodiment is shown in a cross-sectional view in FIG. 3 and a plan view in FIG. A hybrid type (or dual mode type) ink jet recording apparatus having a printing process capable of performing decoloring ink printing and permanent ink printing independently and a decoloring process. The printing process is composed of a carriage having a permanent ink cartridge 5-1 and a carriage having a decoloring ink cartridge 5-2, and each is independent as indicated by an arrow 7 in FIG. Scanned. An arrow 7-1 indicates scanning of the permanent ink cartridge 5-1, and an arrow 7-2 indicates scanning of the decoloring ink cartridge 5-2. Although only one color is shown in FIG. 4 for the erasable ink cartridge, it may be multicolored.

  As one specific embodiment of the decoloring process, it was determined that the heating method using the sheet-like heating element 6-1 was the most reliable method. FIG. 5 is a sectional view. In the sheet-like heating element 6-1, a heating element made of a nickel alloy foil having a power density of 2 W / cm 2 is arranged in a dense pattern on a 1 mm thick silicone rubber substrate lined with a heat insulating material. The side opposite to the silicone rubber substrate (the side on which the object is heated) is insulated by a heat-resistant film (for example, polyimide film) having a thickness of 50 μm, and the surface is in contact with a foil stainless sheet having a thickness of 100 μm. . The sheet-like heating element 6-1 has a width of 1 cm in the paper path direction (the width of the heater and the width of the stainless steel sheet is 0.6 mm) and a length of 22 cm in the direction perpendicular to the paper path. 27W. The stainless steel sheet temperature is controlled at 70 ° C.

A light pressure contact roller 6-2 is disposed facing the sheet heating element 6-1, and conveys paper while lightly pressing the sheet heating element 6-1. It is made of silicone rubber having a rubber hardness of 30 degrees, and is lightly pressed against the sheet-like heating element 6-1 and rotated so that the nip width is about 3 mm.

  The decolorized ink printing paper that has been used reaches the nip portion between the sheet heating element 6-1 and the feed roller 6-2 while being guided by the feed lower guide plate 10-1 by the feed roller pair 8, and is fed. It is sent out while being pressed lightly. The ink is designed to decolor at 60 ° C. Characters and drawings printed with this ink are lightly pressed against the sheet-like heating element 6-1 in this step, and are immediately decolored by receiving heat. The printing paper is further guided by the lower delivery guide 10-2 and the upper guide 10-3, reaches the delivery roller pair 9 and is sent to the printing process 5.

  Here, the roller 9-1 in contact with the printing surface of the delivery roller was a metal roller. In particular, the diameter was increased, for example, a thick aluminum roller having a diameter of 3 cm. These considerations are for lowering the temperature of the printing paper that has received heat in the decoloring step 6. Basically, the amount of heat given is very small, so it is not necessary, but it is to bring it to the safer side. The configuration including the specific design values described above is a typical example of a heating method using a sheet-like heating element, and is applied to a recording apparatus with a printing speed of 20 to 30 sheets of A4 size paper per minute. The material, thickness, pressure, and dimensions are merely typical examples, and it is obvious that various other combinations are possible. The design value changes depending on the specifications of the recording apparatus.

Another decoloring method is a friction method. A slip roller is provided instead of the sheet heating element 6-1. Although not shown, a roller made of an abrasion-resistant elastomer is rotated at a peripheral speed 1.5 to 3 times the paper feed speed, and the print surface is slip rubbed. Discoloration occurs due to the generated frictional heat. When the trailing edge of the paper leaves the feeding roller pair 8, the slip roller rotation is reduced to the paper feeding speed in synchronization.

When the “Decolorable ink printing” check box on the “Basic setting screen” of the computer is checked and “Decolorable ink printing mode” is selected, the “Decolorable ink printing mark” is set for the print part such as the header part. Print out of the margin of the area. As described above, the purpose is to prevent misuse. FIG. 6 is an example of a screen printed with decolorizable ink. In this example, an [Erasable] mark 11 is printed outside the upper right column. The design of this mark is one of the design items.

  The printing of “decolorable ink printing mark” is preferably using permanent ink. This is because it is desired to avoid printing with erasable ink, erasing, then printing with permanent ink, and using this as an official print, not for temporary use. Normally, this is not a special problem, but if this printed matter is left for a long time at, for example, zero degrees or less, the previously erased ink print contents that had disappeared may appear slightly. Once you have printed with decolorizable ink, it is better to keep the “mark” with ink that will not disappear, in order to prevent such mistakes caused by memory alone.

There are other methods of using this “mark for decoloring ink printing”. First, the apparatus is provided with a “mark” detection device in the paper conveyance path. The following functions are incorporated in the printer driver. Basically, when the “decolorable ink printing” check box is checked, the “decolorable ink printing mode” is set. In addition, when reusing erasable ink-printed paper, even if the check box is not checked, this function is automatically incorporated when the detection device detects “mark” and enters the decoloring reprint mode. I will leave it. Even if the erasing device detects the “mark” and enters the operation mode and starts feeding paper, the paper conveyance is temporarily stopped until the sheet heating element reaches the predetermined temperature, and the conveyance is resumed when the predetermined temperature is reached. To do. Then, the color is erased and the color erase printing is performed again.

  Although the present invention has been mainly described with respect to an inkjet recording apparatus as a consumer product, it can also be applied to a business use printer, a portable printer, a large format printer, or an industrial printer. It can be applied to all ink jet products that require trial printing or temporary private printing.

1 Erasable inkjet recording device
2 Paper cassette 4 Paper path 5 Printing process 5-1 Permanent ink cartridge 5-2 Erasing ink cartridge 5-11 Permanent ink cartridge mounting carriage 5-21 Erasing ink cartridge mounting carriage 6 Erasing process 6-1 Sheet-like Heating element 6-2 Light pressure contact roller 9-1 Feed roller 11 Prevention of misuse

Claims (5)

In an inkjet recording apparatus, at least a step of printing using a color erasing ink and a color erasing step of erasing all printed contents of a printed matter printed using the color erasing ink before the printing step. An ink jet recording apparatus characterized by the above. In an ink jet recording apparatus, at least both normal ink jet ink and color erasable ink are mounted, and color erasing that erases all printed content printed using color erasable ink before the printing process. An ink jet recording apparatus having a step and a function of selectively using both inks as necessary. 3. An ink jet recording apparatus according to claim 1, wherein a heating device is used for the decoloring step. 4. An ink jet recording apparatus according to claim 1, wherein when printing with the color erasable ink, a mark clearly indicating that the color erasable ink has been printed is additionally printed on the printed matter. 3. The ink jet recording apparatus according to claim 1, wherein at least the print head for printing with the decolorizable ink is a non-heated print head such as a piezo element.