JP2015221527A - Pre-treatment equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide pre-treatment equipment which can be used again by correcting curvature habits of a recording medium to cutting an unprintable region.SOLUTION: Pre-treatment equipment comprises a plurality of heating means 9a-9f that heat a recording medium 4, first transportation means 5 that transports the recording medium 4 in a reverse direction, second transportation means 6 that transports the recording medium 4 in a forward direction, first buffer means 2 disposed upstream of the first transportation means 5 in a direction of recording medium transportation, second buffer means 3 disposed downstream of the second transportation means 6 in a direction of recording medium transportation, and control means 11 that controls temperatures of heating means 9a-9f, transportation and stop of the recording medium 4, and the transportation direction of the recording medium 4. When a non-operation time turns longer than predetermined time, the control means 11 transports the recording medium 4 with the first transportation means 5 in a reverse direction while heating the heating means 9f positioned most downstream in the direction of recording medium transportation to the heating means 9a positioned most upstream in the same and then transports the recording medium 4 with the second transportation means 6 while heating to an original position.

Description

  The present invention relates to a pretreatment apparatus that is connected to a printing apparatus such as a rotary press or an ink jet continuous book machine and performs a pretreatment on a recording medium.

  In printing devices such as rotary presses and ink-jet printers, ink may bleed along the fibers of the paper during printing (feathering), bleeding at color boundaries (bleeding), or ink may penetrate to the back In some cases, a phenomenon such as show-through may occur and image quality may deteriorate. In order to prevent the occurrence of such a phenomenon, a pretreatment apparatus that applies a treatment liquid (a pre-coating liquid) having an effect of aggregating ink before printing onto a recording medium is used. This pre-processing apparatus has a heat roller for drying ink, processing liquid, etc. on the recording medium. When the printing is stopped, the recording medium stopped on the heat roller causes moisture to evaporate, causing fiber shrinkage, and deforms following the shape of the heat roller. When this deformation occurs, the color superimposition accuracy deteriorates and color misregistration occurs, or the ink on the deformation portion comes into contact with the apparatus or the like, causing ink rubbing, and the print quality deteriorates. Further, when the deformable portion comes into contact with the apparatus, the contacted part of the apparatus may be damaged, or the recording medium may be clogged.

  In order to suppress such an adverse effect resulting from the deformation of the recording medium, a method is employed in which printing is not performed on the deformed portion, and a portion that may be damaged is retracted. As a method for suppressing deformation of the recording medium, a method is known in which the recording medium is reciprocated to disperse the pressed portions in order to prevent the recording medium from being deformed by the pressing roller, although it is not a heat roller portion. This is because the recording medium is deformed by the pressing roller, and the recording medium is intermittently moved in the conveyance direction and the opposite direction during printing in order to provide a device that suppresses deterioration in quality such as whiteout. It is configured such that it is buffered during intermittent movement and reverses the transport direction when the buffer amount reaches a predetermined amount (see, for example, “Patent Document 1”).

However, the above-described method for retracting the contact portion without printing on the deformed portion is merely a countermeasure that does not suppress the deformation of the recording medium itself but does not use the deformed portion. However, there is a problem that the recording medium needs to be discarded and the recording medium becomes useless. In addition, the deformation suppression method using the pressing roller aims to disperse the deformation amount of the recording medium due to pressurization, and the roller shape is caused by the moisture of the recording medium stopped on the heat roller evaporating and causing fiber contraction. There is a problem that the curved wrinkles that are copied cannot be corrected, and the deformed recording medium is wasted.
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide a pre-processing apparatus that can be used again after correcting the curled wrinkles of the recording medium to reduce the unprintable area.

  The present invention includes a plurality of heating means for heating a recording medium, a first conveying means for conveying the recording medium in the reverse direction, a second conveying means for conveying the recording medium in the forward direction, and a first conveying means. The first buffer means disposed upstream of the recording medium conveyance direction, the second buffer means disposed downstream of the second conveyance means in the recording medium conveyance direction, the temperature of the heating means, and the recording Control means for controlling conveyance and stop of the medium and the conveyance direction of the recording medium. When the non-operation time becomes longer than a predetermined time, the control means conveys the recording medium by the first conveyance means. The recording medium is conveyed in the reverse direction while being heated from the heating means located on the most downstream side to the heating means located on the most upstream side, and then the recording medium is heated in the forward direction while being heated to the original position by the second conveying means. It is transported.

  According to the present invention, it is possible to reduce the non-printable area of the paper by heating and reciprocating conveyance of the paper inside the drying apparatus without adding a new configuration, thereby reducing the cost without wasting paper. You can plan.

It is the schematic of the pre-processing apparatus which can apply one Embodiment of this invention. It is the schematic explaining the problem of the pre-processing apparatus used for one Embodiment of this invention. It is the schematic of the printing apparatus and pre-processing apparatus which are used for one Embodiment of this invention. It is the schematic explaining the heater temperature and paper conveyance speed in one Embodiment of this invention. It is a flowchart explaining the operation | movement in one Embodiment of this invention. It is a table | surface explaining the relationship between the paper type information and predetermined time in one Embodiment of this invention.

  FIG. 1 shows a pretreatment apparatus to which an embodiment of the present invention can be applied. A pre-processing apparatus 1 connected to a printing apparatus (not shown) in the figure has a first buffer means 2 at the most upstream position in the sheet conveying direction and a second buffer means 3 at the most downstream position in the sheet conveying direction. . Each of the buffer means 2 and 3 having a fixed roller and a movable roller that can move up and down is configured to store the paper 4 as a recording medium for a predetermined length, and applies tension to the paper 4 by its own weight. ing. The second buffer means 3 stores a sheet 4 having a length that can be safely stopped when a printing apparatus (not shown) connected to the downstream side of the preprocessing apparatus 1 is brought to an emergency stop.

  On the downstream side of the first buffer unit 2 in the sheet conveyance direction, a first conveyance roller pair 5 as a first conveyance unit is disposed. The first conveying roller pair 5 capable of forward / reverse conveyance conveys the paper 4 from a roll paper (not shown) during forward rotation in the forward direction, and during reverse rotation, it conveys in the reverse direction opposite to the forward direction. . A second transport roller pair 6 serving as a second transport unit is disposed upstream of the second buffer unit 3 in the paper transport direction. The second transport roller pair 6 is configured to be capable of forward rotation only, and transports the paper 4 in the forward direction during normal rotation and feeds it to a printing apparatus (not shown). The second transport roller pair 6 is configured to be driven and rotated when the paper 4 is transported in the reverse direction.

  On the downstream side of the first conveyance roller pair 5 in the sheet conveyance direction, there are a first application unit 7 and a second application unit 8 that apply a treatment liquid (a pre-coating liquid) effective to agglomerate ink on the sheet 4. It is arranged. Each of the application means 7 and 8 applies a treatment liquid to both sides of the paper 4. Heat rollers 9 a, 9 b, 9 c, 9 d, 9 e, 9 f, which are a plurality of heating means, are located downstream of the second coating unit 8 in the paper transport direction and upstream of the second transport roller pair 6 in the paper transport direction. Is provided. The paper 4 coated with the treatment liquid on both sides thereof by the application means 7 and 8 is dried in the treatment liquid applied when passing through the heat rollers 9a to 9f of the drying device 9, and is in a print standby state. It is stored in the second buffer means 3.

  Below the apparatus main body of the pre-processing apparatus 1, a control means 11 comprising a well-known microcomputer having a CPU, a ROM, a RAM and the like is disposed. The control means 11 determines whether or not to perform the paper deformation correction process according to various conditions (heat roller temperature, printing standby time, paper type) described later. The control unit 11 performs operation control including the rotation direction and rotation time of the first conveyance roller pair 5 and the second conveyance roller pair 6 and temperature control of the heat rollers 9a to 9f.

  In the pre-processing device 1 described above, when the connected printing device is changed from the printing state to the standby state, the temperature of each of the heat rollers 9a to 9f does not decrease immediately, but from a state where the temperature is maintained higher than the surroundings. The temperature gradually decreases. Therefore, a temperature gradient or a moisture difference between the front and back surfaces is generated between the portion of the paper 4 that is in contact with each of the heat rollers 9a to 9f and the portion that is not in contact, and deformation occurs. The deformation of the paper 4 appears in a shape that follows the outer shape of each of the heat rollers 9a to 9f as shown in FIG.

  As shown in FIG. 3, the pretreatment device 1 is connected to a printing device 10 having an ink jet head for discharging ink in its printing unit, and the paper 4 fed into the printing device 10 passes through a conveyance roller, a guide roller, and the like. Supplied to the printing section. Here, since the gap between the ink jet head and the paper 4 is about 1 to 2 mm, the paper 4 may come into contact with the ink jet head if the deformation amount of the paper 4 is 1 mm or more. The ink jet head has a plurality of fine ink ejection holes. When the paper 4 comes into contact with the ink jet head, the ink ejection holes are blocked, and the image is deteriorated in a state called nozzle omission. Further, since the paper 4 is transported at a high speed, there is a possibility that the head position may be damaged due to contact with the ink jet head. Therefore, the present invention proposes a deformation correction method for the paper 4 that prevents the occurrence of such problems.

  As shown in FIG. 4, at the same time when printing by the printing apparatus 10 is stopped, the heater power of each of the heat rollers 9a to 9f is turned off, the temperature starts to decrease, the paper transport speed becomes 0, and the printing standby is the non-operation time. It becomes a state. Since each of the heat rollers 9a to 9f is naturally cooled in the print standby state, it takes time until the temperature decreases (sheet deformation factor 1: heat roller temperature during print standby). When the printing standby state continues for a long time, the paper deformation progresses (paper deformation factor 2: printing standby time), and the time when the paper deformation exceeds the allowable value varies depending on the paper type (thickness, coated paper or plain paper) (paper) Deformation factor 3: paper type). Therefore, it is necessary to input paper type information used for printing. This paper type information may be input to either the printing apparatus 10 or the preprocessing apparatus 1.

  Subsequently, if the paper deformation can be corrected beyond the time when the paper deformation occurs, the process proceeds to the paper deformation correction process when the print signal is received. When the waiting time is short and the sheet does not deform, the sheet deformation correction process is not performed and the printing operation is started immediately. If the waiting time is too long and correction cannot be completed by the paper deformation correction process, printing is performed after discarding the deformed portion of the paper as it is.

  In the paper deformation correction process, when a print signal is received, the heater is first turned on and the temperature of each of the heat rollers 9a to 9f rises. When the temperature of each of the heat rollers 9a to 9f reaches a predetermined temperature, the first conveying roller pair 5 is reversed to convey the paper 4 in the reverse direction. At this time, the first paper deformation correction process (operation for correcting curling of the paper 4 by the heat rollers 9a to 9f) is performed on the paper 4. The transport distance of the paper 4 is a distance sufficient for the paper 4 staying on the drying device 9 to be discharged from the drying device 9, that is, the distance at which the paper 4 on the heat roller 9f is transported to at least the heat roller 9a. And At the time of conveyance in the reverse direction, the sheet 4 is supplied from the second buffer means 3 and therefore has no influence on the printing apparatus 10. The paper 4 discharged and conveyed from the drying device 9 is stored in the first buffer means 2.

  When the conveyance of the paper 4 in the reverse direction is completed, the second conveyance roller pair 6 is rotated forward so that the paper 4 is conveyed in the normal direction. At this time, the paper deformation correction process for the second paper 4 is performed, and the paper 4 is conveyed to the original position. The deformation of the paper 4 is corrected by the two paper deformation correction processes, and when the paper 4 returns to the original position, the print standby state is resumed.

  FIG. 5 is a flowchart showing the operation of the paper deformation correction process. First, after the paper is set (ST01), information on the paper type is input (ST02). As described above, this information may be input on either the printing apparatus 10 side or the preprocessing apparatus 1 side. Subsequently, a printing operation is started (ST03), and a standby state is entered when the first printing operation is completed (ST04). Thereafter, when the second and subsequent print signals are received (ST05), it is determined whether or not the standby time is within a predetermined time that is the deformation allowable time (ST06). If it is within the predetermined time, the printing operation is started (ST08), and if the predetermined time is exceeded, the paper deformation correction process is performed.

  According to the above-described configuration, it is possible to reduce the non-printable area of the paper by heating and reciprocating the paper inside the drying apparatus without adding a new configuration, thereby reducing the cost without wasting paper. Can be achieved. Further, by adopting a configuration in which the control unit 11 controls the temperature of each of the heat rollers 9a to 9f based on the paper type information, it is possible to prevent the paper from being insufficiently corrected and from giving an excessive amount of heat. In addition, by adopting a configuration in which the control unit 11 determines the deformation amount of the paper from the paper type information and a predetermined time, the time until the printing is completed after determining the necessity of the paper deformation correction process by grasping the paper deformation amount. Can be minimized.

  Furthermore, by adopting a configuration in which the control unit 11 determines a predetermined time that is a deformation allowable time based on the paper type information, the paper deformation correction process can be performed for any paper. A specific example of a configuration in which the control unit 11 determines the predetermined time based on the paper type information will be described below. As shown in FIG. 6, the minimum necessary items as the paper type information to be input to the apparatus are paper type information and basis weight information. By inputting each information, a standby time as a predetermined time during which deformation can be corrected at a predetermined drying temperature is determined. In this example, as long as the standby time is shorter than the numerical value shown in FIG. 6, it is possible to correct the deformation of the paper by performing the paper deformation correction process.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the specific embodiments described above, and is described in the claims unless specifically limited by the above description. Various modifications and changes can be made within the scope of the present invention.
The effects described in the embodiments of the present invention are only the most preferable effects resulting from the present invention, and the effects of the present invention are not limited to those described in the embodiments of the present invention. .

DESCRIPTION OF SYMBOLS 1 Pre-processing apparatus 2 1st buffer means 3 2nd buffer means 4 Recording medium (paper)
5 1st conveyance means (1st conveyance roller pair)
6 Second transport means (second transport roller pair)
9a-9f Heating means (heat roller)
11 Control means

JP 2012-136313 A

Claims (4)

A plurality of heating means for heating the recording medium;
First conveying means for conveying the recording medium in the reverse direction;
A second conveying means for conveying the recording medium in the forward direction;
First buffer means disposed upstream of the first transport means in the recording medium transport direction;
Second buffer means disposed downstream of the second transport means in the recording medium transport direction;
Control means for controlling the temperature of the heating means, conveyance and stop of the recording medium, and the conveyance direction of the recording medium,
When the non-operation time becomes longer than a predetermined time, the control means causes the first conveying means to move the recording medium from the heating means located on the most downstream side in the recording medium conveying direction to the heating means located on the most upstream side. A pre-processing apparatus that transports the recording medium in the forward direction while heating it to the original position by a second transport unit after transporting in the reverse direction while heating. The pretreatment device according to claim 1,
A preprocessing apparatus, wherein the control means determines the predetermined time based on information from a means for inputting information on a recording medium or a means for acquiring information on a recording medium. The pretreatment device according to claim 2,
The pre-processing apparatus, wherein the control means controls the temperature of the heating means based on the information. The pretreatment device according to claim 2 or 3,
The preprocessing apparatus, wherein the control means determines a deformation amount of the recording medium based on the information and the non-operation time.

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