JP2018039180A - Thermal transfer printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To extend the service life of a thermal head by reducing application of a load to a specific heater element of the thermal head even when printed matters in which fixed patterns and variable information are mixed are continuously printed by using an intermediate transfer type thermal transfer printer.SOLUTION: A thermal transfer printer stores the history of the pulse amount applied to each heater element at the latest image formation with replacement every time image formation is performed regarding the pulse amount applied to each heater element of a thermal head, extracts the heater element with the high load in comparison to the pulse amount at the time of new image formation, and shifts photographic data in accordance with the extracted heater element.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an intermediate transfer printer that transfers an image to an object to be processed such as a card, a booklet, a form, a molded product, a paper product, or the like.

  A method of forming an image by thermal head printing using an ink ribbon is already a well-known technique, and is used for various purposes such as printing on a card, outputting a photographic image, and printing on a seal. However, many of these printing methods have a problem that a specific image receiving layer needs to be provided on the surface of the medium, and the combination thereof is limited.

  Therefore, an ink ribbon is used to form an image on an intermediate transfer film having a specific image-receiving layer, and then re-transferred to a transfer target, so that a multicolor image can be obtained regardless of the substrate of the final printing medium. As a technique that can be formed, an intermediate transfer method has been proposed (for example, Patent Document 1).

  Such a printer develops the print data sent from the host device through the external bus on the buffer memory, and sends a current pulse corresponding to the sent print data to each heating element of the thermal head. By supplying, the heat generating element generates heat, and an image is transferred from the ink ribbon to the intermediate transfer film.

  The intermediate transfer method has been mainly used as a means for forming a multicolor image on different substrates such as a passport and an ID (Identification) card. However, passports and ID cards are often required to be used for a relatively long period of 5 to 10 years, and high durability is required. For this reason, a technique using a hot-melt ink ribbon using a pigment, instead of using a sublimable dye as the ink ribbon, has been proposed (for example, Patent Document 2).

  On the other hand, when continuous printing is performed using a thermal transfer printer using a thermal head, the print screen may be a screen in which a fixed pattern and a variable pattern are combined.

  For example, in a card such as an employee ID card or a membership card, the logo mark of the organization that issues the card is not formed on the card substrate in advance by a printing method, but by a thermal transfer printer. There are cases.

  In such a case, in a specific area where the fixed handle exists, more pulses are sent to a specific heat generating element of the thermal head than heat generating elements in other areas.

  Thermal heads used in thermal transfer printers, etc. employ line-type thermal heads in which a large number of heating elements are arranged in a row. The life of this line-type thermal head is generally the running life (the length of the printed media in the feed direction). And the pulse life (corresponding to the number of times the current pulse is applied to the heating element).

  Therefore, when the same printing is always required at the same position as in the fixed pattern as described above, the heat generating element in the printed portion is used more frequently and the life is shortened compared to the heat generating elements in other areas. End up.

When the life of some of the heating elements is exhausted, the portion becomes a toothless print, so even if the life of some of the heating elements is exhausted, the thermal head It can no longer be used.

  In order to solve such a problem, Patent Document 3 discloses a technique for avoiding the concentration of pulses on a specific heating element.

  That is, according to Patent Document 3, when the basic print data is D, the shift timing is shifted by 1 to 3 dots (one dot corresponds to one heating element) based on the print data D. Print data D-1, D-2, and D-3, and when passing through a shift register that sends the pulses applied to the heat generating elements in parallel, D-1 to D-3 are set according to the number of prints. By changing and printing, it is avoided that heat is concentrated on the same place.

  However, in this method, there is a problem that the shift amount (1 to 3 dots) of the applied pulse appears as it is as a shift of the image on the surface of the transferred material, and the shift amount can be confirmed by visual comparison.

JP-A-6-106740 Japanese Patent Laid-Open No. 10-58728 JP-A-5-31942

  The present invention has been made in consideration of the above circumstances, and the object of the present invention is to use a heating element of a thermal head in an intermediate transfer printer even when a combined image of a fixed pattern and a variable pattern is printed. The thermal transfer printer is intended to extend the life of the thermal head and to prevent the deviation of the image on the sheet surface of the transfer target.

  According to a first aspect of the present invention for achieving the above object, there is provided a plurality of arranged plural images for forming an image by heating an ink ribbon on an intermediate transfer film in which at least a transfer layer is detachably provided on a substrate. An image to be formed on the intermediate transfer film, comprising: a thermal head having a heating element; and a retransfer means for retransferring an image formed on the intermediate transfer film to a transfer target. Calculating means for calculating a pulse amount to be applied to each heating element in accordance with print data corresponding to each pixel constituting each pixel, and each heat generation used at the time of the latest image formation every time image formation is performed The storage means for replacing and storing the history of the pulse amount applied to the element, the history of the stored pulse amount and the pulse amount to be applied are compared, and each heating element of the thermal head is compared. And a shift means for shifting the print data applied to the thermal head along the direction in which the heat generating elements are arranged in accordance with the extracted heat generating elements. And a thermal transfer printer.

  Further, the second invention further includes setting means for arbitrarily setting a frequency of comparing the stored pulse amount history and the pulse amount to be applied, for each set number of times of printing. Further, the stored pulse amount history and the pulse amount to be applied are compared, and print data applied to the thermal head is arranged according to the extracted heat generating elements. The thermal transfer printer according to claim 1, wherein the thermal transfer printer is shifted along a specified direction.

  According to a third aspect of the present invention, when the position of the heat generating element applied by the shift means is shifted, the intermediate transfer film, the ink ribbon transport unit, and the transfer target transport unit have a width relative to the thermal head. 3. The thermal transfer printer according to claim 1, further comprising moving means for moving the direction conveying position in the same direction as the image data shifting direction.

  According to the present invention, in the intermediate transfer printer, even when a combined image of a fixed pattern and a variable pattern is continuously output, the life of the thermal head can be extended, and the sheet image of the transfer object can be misaligned. It is possible to provide a thermal transfer printer that does not generate the thermal transfer printer.

It is the schematic which shows the example of a thermal transfer printer. It is a top view which shows the example of the to-be-transferred body in which the image was formed. (A) Previous output card (B) Current output card It is a flowchart which shows the example of a printing by the thermal transfer printer of this invention. It is a conceptual diagram which shows the shift of the printing data of this invention. (A) At the time of the previous printing (B) At the time of the current printing It is a flowchart which shows another example of a printing by the thermal transfer printer of this invention. It is the schematic which shows the example of a printing of this invention. (A) Previous print example (B) Current print example It is a side view showing an example of the thermal transfer printer of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that, throughout all the drawings, the same reference numerals are given to components that exhibit the same or similar functions, and redundant descriptions are omitted.

  FIG. 1 is a schematic diagram illustrating a basic configuration example of an intermediate transfer type thermal transfer printer.

  In FIG. 1, an ink ribbon 10 having an ink layer containing at least a pigment and an intermediate transfer film 20 provided with at least a transfer layer on a substrate so as to be peelable are supplied from respective unwinding portions 11, 21. The image is formed on the transfer layer of the intermediate transfer film on the basis of the print data using the thermal head 40.

  Here, in addition to the ink layer containing cyan, magenta, yellow, and black dyes, the ink ribbon 10 includes a special ink layer such as a fluorescent dye ink layer, an adhesive layer made of a thermoplastic resin, and the like in a surface sequential manner. The adhesive layer may be provided, and after forming an image on the intermediate transfer film 20 using the various ink layers, the adhesive layer may be thermally transferred onto the formed image.

  The intermediate transfer film is provided with various layers such as a release layer, a protective layer, a printing layer, an OVD (Optical Variable Device) layer, and an intermediate layer in addition to the receiving layer of the ink layer containing the dye. Also good.

As described above, the image-formed portion of the intermediate transfer film 20 is conveyed up to the heat roll 50 and is disposed so as to be opposed to the transfer target 70 conveyed by the conveyance roller pair 80. The transfer object 7 is transferred from the intermediate transfer film 20 by the heat roller 50 as means.
The image is retransferred with respect to zero.

  FIG. 2 shows an example of a case where cards are continuously issued by the thermal transfer printer 1 as an example of the transfer target 70 on which an image is formed in this way.

  That is, FIG. 2A shows an example of the card output last time, and FIG. 2B shows an example of the card output this time.

  2A and 2B, the fixed pattern printing unit 71 prints the same pattern, and the variable information printing unit 72 prints with a different pattern.

(Longer life of thermal head)
FIG. 3 is a flowchart showing an example when printing is performed by the thermal transfer printer of the present invention.

  In the thermal transfer printer of the present invention, at the start of printing, it is possible to set 201 the frequency (number of times of printing) as to how many times printing data is shifted with respect to the thermal head 40 for extending the thermal head life.

  Next, based on the print data, a pulse amount to be applied to each heating element of the thermal head is calculated 202.

  Then, it is checked whether the number of times of printing has reached 203 with respect to the value of the frequency setting 201 inputted previously. If the number of times of printing has not yet been reached, the printing is carried out as it is 210. An image is formed on the transfer object, and the number 211 of times of printing is performed.

  Eventually, the pulse amount information applied to each heating element at the time of the latest printing is replaced with past information, stored in the memory 213, and the process proceeds to the next printing.

  If the number of times of printing has reached the value of the frequency setting 201 input previously, the amount of pulses at the time of the previous printing stored in the memory is read out 204, and this time calculated in 202 A comparison 205 is made between the pulse amount to be applied and the pulse amount at the previous printing.

  Based on the comparison 205 between the pulse amount at the time of the previous printing and the scheduled application pulse amount, a heating element with a large applied pulse amount, that is, a high load, is extracted 206, and the overlapping of the pulse amount applied to each heating element is extracted. In order to minimize the print data, the shift amount and the shift direction are calculated 207 so that the print data can be shifted to the left or right along the direction in which the heating elements of the thermal head 40 are arranged.

  FIG. 4 shows a shift state of the image data 300 at the previous printing (A) and the image data 301 at the current printing (B).

  In the heating element 41 arranged on the thermal head 40, the heating element portion 411 that printed the fixed pattern at the previous printing (A) is shifted by n1 at the time of the current printing (B), and the fixed pattern is printed. It has moved to the heating element part 413.

  Here, n1 is the number of heating elements arranged on the thermal head, and indicates the number of dots corresponding to the shifted data calculated so as to minimize the overlapping of the heating elements.

When shifting print data, to prevent missing images in the final print,
By performing this shift, it is checked whether or not the entire print data is within the printable area of the thermal head, and whether or not the print data is within the print allowable area of a transfer medium such as a card.

  If it is determined that there is a deviation in at least one of the two checks, the print data shift amount and shift direction calculation 207 is performed again within the range without the deviation.

  When it is determined that it is within the printable area of the thermal head and within the print allowable area of the transfer target, printing is performed 210.

  Next, the count of the number of times of printing is initialized 212, the pulse amount data applied to each heat generating element in the current printing is replaced with the previous data, and stored in the memory 213, and the process proceeds to the next printing.

  As described above, by shifting the print data, the load on the specific heating element is reduced, and the life of the thermal head can be extended.

(Correction of printing position on the transfer medium)
Next, a description will be given of means for correcting fluctuations in the image forming position caused by the shift of the print data in the final printed matter that is continuously issued.

  FIG. 5 is a flowchart showing another example when printing is performed using the thermal transfer printer of the present invention.

  Similar to the flowchart shown in FIG. 3, after calculating 207 the shift amount and the shift direction of the print data, it is checked whether or not the entire print data is within the printable area of the thermal head.

  If it is determined that the thermal head has deviated from the printable area, the print data shift amount and shift direction calculation 207 is performed again.

  When it is determined that there is no deviation, based on the calculated shift amount n1 (dot) of the print data, the moving amount and moving direction of the transport portion of the ink ribbon 10, the intermediate transfer film 20, and the transfer medium 70 are transferred. Is calculated 214.

  Here, the amount of movement of the ink ribbon, the intermediate transfer film, and the transfer medium with respect to the transfer system is n2 (mm), and the heating element array density of the thermal head 40 used in the thermal transfer printer 1 is 600 (dot / inch). In this case, n2 can be represented by the following formula (1).

n2 = n1 * 25.4 / 600 Formula (1)
Further, the moving direction of each medium is the same as the direction in which the print data is shifted along the arrangement direction of the heating elements arranged in the thermal head.

  Based on the movement amount and movement direction of the conveyance unit of each medium calculated as described above, the respective conveyance units are moved 215.

  After shifting the transport section of each medium, printing is performed 210, the count of the number of times of printing is initialized 212, and the pulse amount data applied to each heating element at the time of printing this time is replaced with the previous data, The data is stored in the memory 213, and the process proceeds to the next print.

  FIG. 6 shows the state of the print image on the intermediate transfer foil when the above-described shift of the print data and the movement of the transport section of each medium are carried out.

  FIG. 6A shows a state in which a print image 310 is formed on the intermediate transfer film 20 based on the previous print data. FIG. 6B shows that the current print data is shifted by n1. In addition, a state is shown in which the printed image 311 is formed on the intermediate transfer film 20 by moving the transport unit of each medium by n2.

  As a result, in the heat generating elements 41 arranged in the thermal head 40, it is possible to avoid applying a high load to a specific heat generating element, to extend the life of the thermal head, and to print in the width direction of each medium. By making the position constant, it becomes possible to make the arrangement state of the image in the final printed matter constant.

  Here, in the movement of the transport section of each medium, in addition to each roller 30 in the transport path of the ink ribbon 10 and each roller 30 in the intermediate transfer film transport path shown in FIG. It is desirable to include each unwinding part 11 and 21 and each winding part 12 and 22 so that wrinkles etc. may not occur during conveyance.

  In addition, in the transfer system for the transfer target, if a guide unit for the transfer target is provided in addition to the transfer roller pair 80, it is desirable to move these also at the same time.

  In order to move the transfer unit as described above, a method may be used in which an actuator is individually provided for each transfer system component, and each is moved.

  Further, as shown in FIG. 7, a moving stage 101 is provided in the casing 100 of the thermal transfer printer 1, a medium transport unit 103 is supported on the moving stage 101, and a thermal head support that supports at least a thermal head. A structure in which the portion 104 is supported on the housing 100 side may be provided.

  Thereby, by moving the moving stage 101 by the actuator 102, the entire medium transport unit 103 can be moved simultaneously, and the structure can be simplified.

  As described above, by using the thermal transfer printer of the present invention, even when a printed matter in which a fixed pattern and variable information are mixed is output continuously, a load is applied to a specific heating element on the thermal head. Therefore, it is possible to extend the life of the thermal head, and even when the image data is shifted and printed, it is possible to provide a printed product having no variation in image position in the final printed product.

DESCRIPTION OF SYMBOLS 1 ... Thermal transfer printer 10 ... Ink ribbon 11 ... Ink ribbon winding part 12 ... Ink ribbon winding part 20 ... Intermediate transfer film 21 ... Intermediate transfer film winding part 22 ... Intermediate transfer film winding part 30 ... Roller 40 ... Thermal head DESCRIPTION OF SYMBOLS 41 ... Heat generating element 50 ... Heat roller 60 ... Platen roller 70 ... Transfer object 71 ... Fixed pattern printing part 72 ... Variable information printing part 80 ... Conveying roller pair 100 ... Housing 101 ... Moving stage 102 ... Actuator part 103 ... Medium Transport unit 104 ... Thermal head support unit 201 ... Frequency (number of times of printing) 202 ... Calculation of scheduled application pulse amount 203 ... Confirmation of application frequency 204 ... Reading of previous pulse amount 205 ... Comparison between previous pulse amount and scheduled application pulse amount 206 … Extraction of heat-generating elements with high load 207… Printing Calculation of data shift amount and direction 208 ... Confirmation of whether within thermal head printable area 209 ... Confirmation of whether within transfer allowable area of transfer target 210 ... Printing execution 211 ... Count of number of times of printing 212 ... Reset of number of times of printing 213 ... Replacement of each pulse amount data at the time of printing 214 ... Calculation of movement amount and direction of each medium conveyance unit 215 ... Movement of each medium conveyance unit 300 ... Previous printing data 301 ... Current printing data 310 ... Previous printing image 311 ... Current printing image 411, 413 ... fixed pattern printing heat generating element part 412, 414 ... variable information printing heat generating element part n1 ... print data shift amount n2 ... medium (intermediate transfer film) shift amount

Claims (3)

A thermal head having a plurality of arranged heating elements for forming an image by heating an ink ribbon on an intermediate transfer film in which at least a transfer layer is detachably provided on a substrate, and on the intermediate transfer film A thermal transfer printer comprising a re-transfer means for re-transferring the image formed on the transfer medium,
Calculating means for calculating a pulse amount to be applied to each heating element according to print data corresponding to each pixel constituting an image formed on the intermediate transfer film;
Storage means for replacing and storing the history of the pulse amount applied to each heating element used at the time of the latest image formation every time image formation is performed;
By comparing the history of the stored pulse amount and the pulse amount to be applied, in each heating element of the thermal head, an extraction means for extracting a heating element having a high load, and the extracted heating element Accordingly, the thermal transfer printer includes: shift means for shifting the print data applied to the thermal head along the direction in which the heating elements are arranged.   It further has a setting means for arbitrarily setting the frequency of comparing the history of the stored pulse amount and the pulse amount to be applied, and the stored pulse amount for each set number of times of printing. And the print data applied to the thermal head according to the extracted heating elements are shifted along the direction in which the heating elements are arranged. The thermal transfer printer according to claim 1, wherein:   When the position of the heating element applied by the shift means shifts, the conveyance position in the width direction with respect to the thermal head in the conveyance section of the intermediate transfer film and the ink ribbon, and the conveyance section of the transfer target, 3. The thermal transfer printer according to claim 1, further comprising moving means for moving in the same direction as the image data shifting direction.