JP2009090500A - Thermal transfer printer and control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To optimally set the energy amount to be applied to a thermal head for each of acceptable sheets to be used, and to perform printing on the sheet. <P>SOLUTION: In the thermal transfer printer 100 including the thermal head 27 that transfers ink from a thermal transfer ink ribbon 24 to the acceptable sheet 21, and configured to control the energy amount to be applied to the thermal head 27 according to the type of the thermal transfer ink ribbon 24 and an environment temperature, the thermal transfer printer 100 includes: a heat diffusivity group table 13 specifying which one of heat diffusivity group the acceptable sheet 21 to be used belongs to among a plurality of heat diffusivity groups classified according to the level of the heat diffusivity; and a group information table 14; a modification table 15 where the correction coefficient of the energy amount to be applied by the thermal head control means is stored according to the specified heat diffusivity group of the acceptable sheet 21; and an application energy calculation part 12 for deciding the energy amount to be applied according to the obtained correction coefficient. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a thermal transfer printer and a control method for the thermal transfer printer, and more particularly, to a thermal head that transfers a transfer ink of a thermal transfer ink ribbon onto a receiving paper, and the energization amount to the thermal head is determined according to the type and environmental temperature of the thermal transfer ink ribbon. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer printer that is controlled based on the control method and a thermal transfer printer control method.

  The above-described thermal transfer printer is used for a POS terminal, an electronic cash register, a barcode printer, a measuring instrument, and the like. In such a thermal transfer printer, predetermined thermal energy is applied to the thermal transfer ink ribbon by a thermal head, and the ink of the thermal transfer ink ribbon is thermally transferred to the receiving paper for printing.

  In a thermal transfer printer, the print quality varies depending on the environmental temperature. Therefore, when the environmental temperature is low, it is necessary to increase the amount of energy applied to the thermal head. If the amount of voltage applied to the thermal head is constant, it is necessary to set the application time longer.

  In such a thermal transfer printer, there are many types of receiving paper and thermal transfer ink ribbon used.

  That is, there are paper-type, PP-type and PET-type as receiving paper, and wax-type, semi-resin-type and resin-type inks as thermal transfer ink ribbon ink. The receiving paper and the thermal transfer ink ribbon are used in appropriate combination. Generally, a wax-based ink is used for the paper-based receiving paper, and a semi-resin-based for the PP-based PET receiving paper. Resin-based ink is used.

  Here, the amount of energy applied to the thermal head necessary for obtaining good print quality differs depending on the combination of the receiving paper and the thermal transfer ink ribbon, and these optimum values cannot be uniquely determined.

  For this reason, conventionally, in such a thermal transfer printer, in order to obtain good print quality, an optimum value of the amount of energy applied to the thermal head is designated and set for the combination of the receiving paper and the thermal transfer ink ribbon. As the optimum value of the applied energy, a good print sample is selected from the print samples obtained by actually changing the applied energy amount to the thermal head for various combinations of receiving paper and thermal transfer ink ribbon. The value when the sample is obtained is specified.

  In the thermal transfer printer, the value of the applied energy amount thus obtained is tabulated, and the applied energy amount is determined by referring to this table from the receiving paper and the thermal transfer ribbon to be used for control.

  The following is what changes the amount of energy applied to the thermal head based on the environmental temperature. Patent Document 1 discloses a thermal head that performs recording by applying heat to recording paper in order to control the recording density by a simple method without complicating the structure and control and to keep the recording time constant. By changing the duty of the strobe signal to be applied according to the parameters that affect the heat generation capacity, that is, the temperature or environmental temperature of the thermal head, the resistance value, and the supply voltage, the heat generation capacity of the thermal head is controlled and uniform printing is performed. What gets the concentration is described.

JP-A-7-299925

  However, in the above-described thermal transfer printer, when the consumer uses a new type of receiving paper, the amount of energy applied by the thermal head is not specified in the table. It is necessary to carry out test printing with an appropriate amount of applied energy to determine the optimum amount of applied energy. In addition, since there is no confirmation that the amount of applied energy determined in this way is optimal, there is a demand for the user to be able to determine the amount of applied energy suitable for the receiving paper used easily.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a thermal transfer printer that can perform printing by setting an optimum amount of energy applied to a thermal head for each receiving paper to be used.

  In order to solve the above-described problems, a thermal transfer printer according to the present invention is a thermal head that transfers ink from a thermal transfer ink ribbon to a receiving paper, and the amount of energy applied to the thermal head based on the type and environmental temperature of the thermal transfer ink ribbon. A thermal transfer printer comprising: an energy correction device that corrects the amount of energy applied to the thermal head control means based on the thermal diffusivity of the receiving paper used. is there.

  According to the present invention, the energy applied to the thermal head is determined by the environmental temperature and the type of thermal transfer ink ribbon used, and is corrected based on the thermal diffusivity of the receiving paper used. The thermal head can be heated with an applied energy amount adapted to the above, and optimal printing can be performed.

  Embodiments of a thermal transfer printer according to the present invention will be described below with reference to FIGS.

  First, the basic concept of the present invention will be described. The inventor conducted printing experiments by combining various receiving papers and thermal transfer ink ribbons. As a result of considering this result and the relationship between the thermal diffusivities of each receiving paper, the receiving paper is divided into groups according to the thermal diffusivity, and the amount of energy applied to the thermal head is changed corresponding to this group. And found that the optimum printing results can be obtained. An example of a printing experiment will be described below.

  FIG. 10 is a diagram showing a result of a printing experiment in the thermal transfer printer. In this experiment, six types of receiving papers A, B, C, D, E, and F (denoted as a substrate in the figure), five types of thermal transfer ink ribbons a, b, c, d, and e Was printed in combination. During printing, the tone value of the thermal transfer printer was changed at a constant rate (tone values 1 to 4: the larger the tone value, the greater the amount of energy applied to the thermal head).

  Here, receiving papers A, B, and C are paper-based, receiving paper D is PP-based, and receiving papers E and F are PET-based. The thermal transfer ink ribbon a is a wax system, the thermal transfer ink ribbon b is a semi-resin system, and the thermal transfer ink ribbons c, d, and e are a resin system. Generally, wax-based inks are used for paper-based receiving papers, and semi-resin-based and resin-based inks are used for PP-based PET receiving papers.

  The combination of thermal transfer ink ribbon a and receiving paper A, B, C is in row I (columns i to iii), and the combination of thermal transfer ink ribbon b and receiving paper A, B, C is row II (columns i to iii). In addition, the combination of the thermal transfer ink ribbon c and the receiving papers D, E, and F is row III (i column to iii column), and the combination of the thermal transfer ink ribbon d and the receiving papers D, E, and F is row IV (i column to iii). In column), combinations of the thermal transfer ink ribbon e and the receiving papers D, E, and F are described in row V (columns i to iii). In the print result of each row and column in the figure, the numbers (1 to 4) described at the top of the print result indicate tone values, and the amount of applied energy increases toward the right side. In addition, the best printing result is surrounded by a wavy line.

  When the thermal diffusivity of each receiving paper A, B, C, D, E, F was measured, it was as shown in FIG. The thermal diffusivity of each receiving paper was measured with a laser flash method thermal constant measuring device manufactured by ULVAC-RIKO.

  The following can be understood from the above results. First, when the same thermal transfer ink ribbon is used, in order to obtain the same level of printing results, it is necessary to apply a larger applied energy as the thermal diffusivity of the receiving paper is larger.

  For example, regarding receiving sheet A (i column) and receiving sheet B (line ii) using the same thermal transfer ink ribbon a in line I, tone value 3 is optimal for receiving sheet A, and tone value for receiving sheet B. 2 is optimal, and in line III, the receiving paper D (line i) and receiving paper E (line ii) using the same thermal transfer ink ribbon c are considered to have a tone value of 1 for the receiving paper D and a tone of the receiving paper E. A value of 3 is optimal. A similar tendency is found for the receiving sheets D and E in the IV and V rows.

  In addition, the thermal diffusivity of the receiving paper is grouped into a plurality of stages (in this example, four stages), and the same applied energy is applied to the receiving paper in the same group to obtain the same printing result. For example, regarding the receiving paper B (column ii) and the receiving paper C (column iii) using the same thermal transfer ink ribbon a in the I row, the tone value 2 is optimal for both receiving papers, and the same in the III row. When the receiving paper E (ii row) and the receiving paper F (iii row) using the thermal transfer ink ribbon c are considered, the tone value 3 is optimal for both receiving papers. A similar tendency is found for the receiving sheets E and F in the IV and V rows.

  The thermal transfer printer according to the present invention was created based on the above knowledge, and the thermal transfer printer according to the embodiment has the following configuration.

  FIG. 1 is a block diagram showing a schematic configuration of a thermal transfer printer, and FIG. 2 is a block diagram showing an electrical configuration of the thermal transfer printer.

  The thermal transfer printer 100 includes a control unit 10 that controls the apparatus and a mechanism unit 20 that executes printing. The mechanism unit 20 applies the applied energy from the thermal head 27 to the thermal transfer ink ribbon 24 while moving the thermal transfer ink ribbon 24 in contact with the receiving paper 21 to transfer the ink of the thermal transfer ink ribbon 24 to the receiving paper 21. To do. The receiving paper 21 to which the ink has been thermally transferred is cut into a predetermined length by a cutting mechanism (not shown) and discharged as a printed matter 23. Depending on the type of thermal transfer printer, the paper may be discharged as continuous paper without the cutting mechanism.

  In the mechanism unit 20, the receiving paper 21 is supplied from a receiving paper roll 22 formed by winding the receiving paper. The thermal transfer ink ribbon 24 is supplied from an ink ribbon roll 25 formed by winding up the ink ribbon, and the ink ribbon that has been subjected to the thermal transfer is wound up and collected by the ink ribbon winding roller 26.

  The receiving paper 21 is moved by a receiving paper supply roller 32, a pinch roller 33, and a platen roller 34. The receiving paper supply roller 32 and the platen roller 34 are rotationally driven by a pulse motor 45 (see FIG. 2) of the control unit 10. The thermal transfer ink ribbon 24 is guided by an ink ribbon guide roller 28 that is rotationally driven by a DC motor 46 (see FIG. 2), moves on the platen roller 34 at the same speed as the receiving paper 21, and is thermally transferred. 26 is wound up. Further, the mechanism unit 20 is provided with a thermistor 29 that is a temperature detecting means for measuring the temperature in the vicinity of the thermal head 27.

  The control unit 10 also includes a keyboard 11, an applied energy calculation unit 12, a thermal diffusivity group table 13 that identifies a thermal diffusivity group that belongs based on the thermal diffusivity value of the receiving paper, and the name of the receiving paper. It includes a group information table 14 that identifies a thermal diffusivity group to which it belongs, a correction table 15 that identifies a correction coefficient from the thermal diffusivity group, and a head drive unit 16 that actually applies applied energy to the thermal head 27.

  In the present example, the applied energy calculation unit 12 includes a density setting value correction unit 17 as a unit for correcting the amount of energy finally applied from the head driving unit 16 to the thermal head 27. The density setting value correcting unit 17 corrects the actual applied energy based on the input from the keyboard 11 and corrects the applied energy amount so that the desired density is obtained. The density setting value correcting unit 17 calculates a density setting value (tone value) according to the difference between the correction coefficient corrected by the correction table 15 and the reference applied energy and the ratio of the reference applied energy. A density setting value calculation unit 18 to be connected to a density display unit 19 that displays the calculated density setting value and the finally corrected density setting value.

  In such a thermal transfer printer 100, the keyboard 11 inputs the type of thermal transfer ink ribbon to be used and the type of receiving paper to be used. As the type of the thermal transfer ink ribbon, the manufacturer and name of the thermal transfer ink ribbon are input. As the type of receiving paper, the thermal diffusivity of the receiving paper or the manufacturer and name of the receiving paper are input.

  If the receiving sheet is registered in the group information table 14, the name of the receiving sheet may be input. If the receiving sheet is not registered, the value of the thermal diffusivity is input. For this thermal diffusivity value, reference is made to that provided by the receiving paper manufacturer or the thermal transfer printer manufacturer. A touch panel input device can be used instead of the keyboard 11.

  In the control unit 10, the applied energy calculation unit 12 first calculates a reference applied energy amount from the maximum applied energy amount that can be applied to the thermal head 27 in consideration of the environmental temperature and the type of thermal transfer ink ribbon to be used.

  Next, the control unit 10 refers to the thermal diffusivity group table 13 or the group information table 14 to identify which thermal diffusivity group the receiving paper to use belongs to, and refers to the correction table 15 to the thermal head. The amount of applied energy is corrected. Further, the applied energy amount is corrected based on the correction of the density setting value correction unit 17 set by the input from the keyboard 11. At this time, the tone value based on the corrected energy amount and the tone value based on the corrected energy amount are displayed on the density display unit 19, and the operator can execute printing with a desired tone value. .

  That is, the applied energy calculation unit 12 finally determines the correction applied energy amount based on the type of thermal transfer ink ribbon to be used, the environmental temperature, and the thermal diffusivity group of the receiving paper, and further, the density setting value correction unit 17 The head drive unit 16 is driven with the corrected applied energy amount.

  Here, when the input information about the receiving paper is the thermal diffusivity, the thermal diffusivity group table 13 is referred to, and when the information is the name (brand) of the receiving paper, the group information table 14 is referred to, Identify which group of thermal diffusivity groups it belongs to.

  The control unit 10 has the following electrical configuration. As shown in FIG. 2, the control unit 10 realizes its function with a microcomputer 40. The microcomputer 40 fixes a CPU (Central Processing Unit) 41 that arithmetically processes various input and stored data and controls the operation of each unit, a control program, a thermal diffusivity group table 13, a group information table 14, a correction table 15, and the like. A ROM (Read Only Memory) 42, which is a storage medium for storing target data in advance, and a RAM (Random Access Memory) 43 for storing various data in a rewritable manner are connected via a bus line 44.

  Further, the CPU 41 includes a pulse motor 45 that rotationally drives the receiving paper supply roller 32 and the platen roller 34, a DC (Direct Current) motor 46 that rotationally drives the ink ribbon take-up roller 26, and a head drive unit that drives the thermal head 27. 16, a density display unit 19 and a communication I / F 47 for receiving various data such as print data from a host computer (not shown) are connected via a bus line 44 and various control circuits (not shown).

  The control unit 10 implements the functions of an applied energy calculation unit 12, a density setting value correction unit 17, and a density setting value calculation unit 18 that calculate the amount of energy applied to the thermal head 27 by executing a control program using the microcomputer 40. . As described above, the tone value set by the density setting value correcting unit 17 includes an amount obtained by subtracting the applied energy amount corrected by the correction table 15 from the applied energy amount serving as a reference, and the applied energy amount serving as the reference. The ratio is calculated by the CPU 41. The tone value and the corrected tone value corrected by the density setting value correcting unit 17 are displayed on the density display unit 19.

  The ROM 42 stores the thermal diffusivity group table 13, the group information table 14, and the correction table 15.

  With this configuration, the control unit 10 controls the energy applied to the thermal head 27 in addition to driving the receiving paper 21 and the thermal transfer ink ribbon 24 arranged in the mechanism unit 20.

  Next, the thermal diffusivity group table 13 will be described. The thermal diffusivity group table 13 specifies which thermal diffusivity group the receiving paper belongs to based on the input thermal diffusivity value.

FIG. 3 is a schematic diagram showing the data contents of the thermal diffusivity group table of the thermal transfer printer. In this example, the receiving paper is grouped as follows according to the input thermal diffusivity value.
Group 1: 5.0 × 10 ⁻³ cm ² / s or more Group 2: 4.0 × 10 ⁻³ cm ² / s or more and less than 5.0 × 10 ⁻³ cm ² / s Group 3: 3.0 × 10 ⁻³ cm ² / s or more and less than 4.0 × 10 ⁻³ cm ² / s Group 4: less than 3.0 × 10 ⁻³ cm ² / s Next, the group information table 14 will be described. The group information table 14 specifies which thermal diffusivity group the receiving paper belongs to based on the input name of the receiving paper.

FIG. 4 is a schematic diagram showing data contents of the group information table of the thermal transfer printer. As shown in FIG. 4, the group information table 14 includes thermal diffusivity groups (group 1, group 2, group 3, and the like) to which the receiving paper types (product names) (A, B, C,..., X, Y) belong. Group 4) is designated. Accordingly, the group to which the receiving paper belongs is specified corresponding to the receiving paper. In this example, the thermal diffusivity group is determined as follows.
Group 1: 5.0 × 10 ⁻³ cm ² / s or more Group 2: 4.0 × 10 ⁻³ cm ² / s or more and less than 5.0 × 10 ⁻³ cm ² / s Group 3: 3.0 × 10 ⁻³ cm ² / s or more and less than 4.0 × 10 ⁻³ cm ² / s Group 4: less than 3.0 × 10 ⁻³ cm ² / s These reference values are criteria for grouping in the thermal diffusivity group table 13 Is the same.

  FIG. 5 is a graph showing a group example of thermal diffusivity. Actually, the thermal diffusivities of the receiving papers A, B, C, D, E, and F were measured and grouped according to the above criteria. As a result, A: group 1, B: group 2, C: group 2, D: group 4, E: group 3, and F: group 3.

  Next, the correction table 15 will be described. FIG. 6 is a schematic diagram showing the data contents of the correction table of the thermal transfer printer.

  In this example, the correction table 15 defines a correction coefficient r based on a group depending on the thermal diffusivity of the receiving paper and the product name of the thermal transfer ink ribbon to be used. For example, when the ink a is used and the receiving sheet of the thermal diffusivity group 1 is used, the correction coefficient “0” is used. When the ink a is used and the receiving sheet of the thermal diffusivity group 2 is used, the correction coefficient r is set to “−0. 06 ”, the correction coefficient r is“ −0.15 ”when the ink a is used and the receiving sheet of the thermal diffusivity group 3 is used, and the correction coefficient r is set when the ink a is used and the receiving paper of the thermal diffusivity group 4 is used. r is set to “−0.24”. Here, the correction coefficient r is determined as follows. Each correction coefficient is determined by performing test printing using each thermal transfer ink ribbon for each diffusivity group.

  When obtaining the correction energy amount, the correction energy amount is calculated based on the correction formula: Er = (1 + r) Es, where Es is the reference applied energy amount, Er is the correction energy amount, and r is the correction coefficient.

  Next, the operation of the thermal transfer printer according to the embodiment will be described.

  FIG. 7 is a flowchart showing the operation of the thermal transfer printer. First, when the thermal transfer printer is used, a reference applied energy amount is calculated (step ST1). The applied energy calculation unit 12 acquires the environmental temperature and the input thermal transfer ink ribbon type (steps ST2 and ST3), and calculates the reference applied energy amount based on the maximum applied energy amount that can be applied to the thermal head 27. Calculate (step ST4).

  When the thermal diffusivity or name of the receiving paper is input (step ST5), when the thermal diffusivity is designated, the thermal diffusivity group table 13 is referred to and the name of the receiving paper is input. Then, the thermal diffusivity group to which the receiving paper belongs is obtained with reference to the group information table 14 (step ST6).

  Then, the correction coefficient is acquired by referring to the type of ink ribbon acquired from the correction table 15 and the thermal diffusivity group of the receiving paper (step ST7). Next, a corrected applied energy amount that is an optimum applied energy amount is calculated from the reference applied energy amount and the correction coefficient (step ST8).

  In this way, the applied energy calculation unit 12 determines the amount of energy applied to the thermal head 27.

  Next, a specific example of determining the correction application energy amount in the thermal transfer printer 100 will be described. In this example, the applied energy calculation unit 12 corrects the amount of energy applied to the thermal head by changing the voltage application time to the thermal head 27. FIG. 8 is a schematic diagram showing the contents of the correction of the energization time by the receiving paper group.

  In this example, the thermal transfer printer 100 uses the thermal transfer ink ribbon a to perform printing at a printing speed of 4 ips, a thermal head resistance of 1000Ω, and an applied voltage of 24V. In this case, if the current per element is 24 mA, the printing width is 4 inches and the resolution is 8 dots / mm, the total number of dots is 832 dots, and the total current is about 20 A.

  Under these conditions, when the thermal transfer ambient temperature is 20 ° C., the maximum applied energy amount to the thermal head is taken into consideration, as shown in FIG. 8A, the applied power is 0.576 (W), and the energization time is The reference energy amount to be applied to the thermal head is 0.609 (μs), and 0.351 (mJ).

  Then, the correction application energy amount is calculated using the correction coefficient r described above. According to the group information table 14, the receiving paper A is the thermal diffusivity group 1. Further, r = 0 for the combination of thermal diffusivity group 1 and thermal transfer ink ribbon a according to the correction table 15, and Er = Es according to the correction equation.

  As a result, as shown in FIG. 8B, the energization time to the thermal head 27 becomes 0.609 (μs) as in the case of applying the reference applied energy amount. As a result, the amount of energy applied to the thermal head 27 becomes 0.351 (mJ).

  Similarly, in the case of receiving papers B and C, since it is thermal diffusivity group 2 and r = −0.06, the correction formula is Er = (1−0.06) Es, and FIG. As shown, the energization time is 0.572 (μs), and the amount of energy applied to the thermal head 27 is 0.33 (mJ).

  Similarly, in the case of the receiving paper D, since it is the thermal diffusivity group 4 and r = −0.24, the correction formula is Er = (1−0.24) Es, and FIG. As shown, the energization time is 0.524 (μs), and the amount of energy applied to the thermal head 27 is 0.267 (mJ).

  Further, in this example, the applied energy calculation unit 12 can control the applied energy amount applied to the thermal head by changing the applied voltage to the corrected applied energy amount. In this case, the application time is fixed (0.609 (μs)).

  FIG. 9 is a schematic diagram showing the contents of correction of the applied voltage by the receiving paper group. In this case, the applied voltage is calculated using the above-described correction formula: Er = (1 + r) Es.

  Under the same conditions as in the example shown in FIG. 8, the applied voltage necessary for applying the reference applied energy amount is 24 volts as shown in FIG. 9A.

  Then, the correction application energy amount is calculated using the correction coefficient r described above. As a result, the receiving paper A is the thermal diffusivity group 1, and as shown in FIG. 9B, the applied voltage to the thermal head 27 is 24 (V as in the case of applying the reference applied energy amount. ) As a result, the amount of energy applied to the thermal head 27 becomes 0.351 (mJ).

  Similarly, in the case of the receiving papers B and C, since it is the thermal diffusivity group 2 and r = −0.06, the correction formula is Er = (1−0.06) Es, and FIG. As shown, the applied voltage is 22.56 (V), and the amount of energy applied to the thermal head 27 is 0.33 (mJ).

  Similarly, in the case of the receiving paper D, since it is the thermal diffusivity group 4 and r = −0.24, the correction formula is Er = (1−0.24) Es, and FIG. As shown, the applied voltage is 0.267 (V), and the amount of energy applied to the thermal head 27 is 0.267 (mJ).

  As described above, according to this example, since an appropriate amount of energy applied to the thermal head is determined by a group of thermal diffusivity determined by the type of receiving paper to be used, appropriate printing can be executed. it can.

  As described above, according to the thermal transfer printer of this example, the energy applied to the thermal head is determined by the environmental temperature and the type of thermal transfer ink ribbon to be used, and the value of the thermal diffusivity of the receiving paper to be used. Therefore, the thermal head can be heated with an applied energy amount suitable for the receiving paper to be used, and optimal printing can be performed. In this case, when using the receiving paper registered in the group information table of the thermal transfer printer, it is only necessary to input the name of the receiving paper, and when using a new receiving paper not registered in the group information table, The thermal head can be heated with an applied energy amount suitable for the receiving paper to be used simply by inputting the value of the thermal diffusivity of the receiving paper, and optimum printing can be performed.

  In the first example, the case where the name of the receiving paper is input to obtain the correction coefficient r has been described. However, the thermal diffusivity of the receiving paper is input and the thermal diffusion rate is referred to the thermal diffusivity group table 13. A rate group is acquired, a correction coefficient r is obtained by referring to the correction table 15 from the thermal transfer ink ribbon to be used and the acquired thermal diffusivity group, and the correction applied energy amount can be calculated.

  Further, in the present invention, the correction coefficient r can be determined from the input thermal diffusion coefficient of the receiving paper by a direct calculation formula. That is, the correction coefficient r determined by referring to the thermal diffusivity group table, the group information table and the correction table in the above example is directly calculated by the CPU. Therefore, in the thermal transfer printer according to this example, the thermal diffusivity group table, the group information table, and the correction table are not necessary, and the control unit calculates the correction coefficient r based on the following correction coefficient formula and energy formula.

  Hereinafter, an example in which the correction coefficient is determined based on the input thermal diffusivity value and the applied energy is corrected will be described.

In this example, the correction factor r, for example when the thermal diffusivity is not less than 5.3 × 10 ^-3 cm ² / S correction coefficient 0, in the case of less, calculated based on the correction coefficient formula.

Correction coefficient formula r = 0.084 × thermal diffusivity × 1000−0.45
Therefore, the energy to be applied is given by the following energy equation.

Energy formula Er = (1 + r) × Es
However, Es is the reference applied energy amount and the corrected energy amount is Er as described above.

  For example, taking the case described above as an example, the reference applied energy amount is 0.351 (mJ).

Therefore, when the thermal diffusivity of the receiving paper is 5 × 10 ⁻³ cm ² / S, the correction coefficient r is −0.03, and the correction energy amount to be applied is Er = (1−0.03) × 0. 351 = 0.34 (mJ).

When the thermal diffusivity is 4 × 10 ⁻³ cm ² / S, the correction coefficient r is −0.114, and the correction energy amount to be applied is Er = (1−0.114) × 0.351 = 0. 311 (mJ).

  The above-mentioned calculation conditions and formulas can be determined in advance by experiments, and values and formulas suitable for each condition can be adopted depending on the environmental conditions, various conditions of the thermal transfer printer, and the type of thermal transfer ink ribbon. it can.

  Thus, according to this example, the optimum applied energy amount can be calculated by directly inputting the thermal diffusion coefficient of the receiving paper, and the thermal head can be heated with the applied energy amount suitable for the receiving paper to be used. , Optimal printing can be performed.

  In this example, the thermal diffusivity measured by a laser flash method thermal constant measuring device manufactured by ULVAC-RIKO is used. However, the applied energy depends on the numerical value that changes the state of thermal energy from the thermal head depending on the receiving paper. It goes without saying that a similar result can be obtained even if the correction is made. For example, thermal conductivity and thermal resistance. Further, it may be a means for correcting based on the actual measurement value by actually measuring the thermal temperature of the label immediately after passing through the heat roller experimentally.

  As described above, according to the thermal transfer printer of the present invention, the energy applied to the thermal head is determined by the environmental temperature and the type of thermal transfer ink ribbon to be used, and the value of the thermal diffusivity of the receiving paper to be used. Therefore, the thermal head can be heated with an applied energy amount suitable for the receiving paper to be used, and optimal printing can be performed.

FIG. 2 is a block diagram illustrating a schematic configuration of a thermal transfer printer. It is a block diagram which shows the electric constitution of a thermal transfer printer. It is a schematic diagram which shows the data content of the thermal diffusivity group table of a thermal transfer printer. It is a schematic diagram which shows the data content of the group information table of a thermal transfer printer. It is a graph which shows the group of thermal diffusivity. It is a schematic diagram which shows the data content of the correction table of a thermal transfer printer. It is a flowchart which shows the action | operation of a thermal transfer printer. It is the schematic which shows the content of the correction | amendment of the electricity supply time by the group of receiving paper. It is the schematic which shows the content of the correction of the applied voltage by the group of receiving paper. It is a figure which shows the state of the test print of a thermal transfer printer. It is a figure which shows the thermal diffusivity of the receiving paper A, B, C, D, E, and F.

Explanation of symbols

DESCRIPTION OF SYMBOLS 12 ... Applied energy calculation part, 13 ... Thermal diffusivity group table, 14 ... Group information table, 15 ... Correction table, 16 ... Head drive part, 17 ... Density setting value correction part, 18 ... Density setting value calculation part, 19 ... Density display section, 21 ... receiving paper, 24 ... thermal transfer ink ribbon, 27 ... thermal head

Claims (13)

A thermal head that transfers ink from the thermal transfer ink ribbon to the receiving paper; and
In a thermal transfer printer comprising a thermal head control device that controls the amount of energy applied to the thermal head based on the type of the thermal transfer ink ribbon and the environmental temperature,
A thermal transfer printer comprising an energy correcting device for correcting the amount of energy applied to the thermal head control means based on the thermal diffusivity of the receiving paper used. The energy correction device includes:
Means for entering the value of the thermal diffusivity of the receiving paper used;
Means for correcting the amount of energy applied to the thermal head control device based on a correction coefficient obtained by inputting the value of the thermal diffusivity of the input receiving paper into a predetermined correction equation;
The thermal transfer printer according to claim 1, further comprising: The energy correction device includes:
Means for specifying which thermal diffusivity group of a plurality of thermal diffusivity groups the receiving paper used belongs to according to the magnitude of thermal diffusivity;
Means for correcting the amount of energy applied by the thermal head control device based on the thermal diffusivity group of the identified receiving paper;
The thermal transfer printer according to claim 1, further comprising: The energy correction device includes:
Means for entering information identifying the type of receiving paper to be used;
Means for specifying which thermal diffusivity group of the plurality of thermal diffusivity groups the input receiving paper belongs to from the type of the input receiving paper;
The thermal transfer printer according to claim 1, further comprising:   5. The thermal transfer printer according to claim 1, further comprising means for further correcting the applied energy amount corrected by the energy correcting device.   5. The thermal transfer printer according to claim 4, wherein the information specifying the type of receiving paper is a value of thermal diffusivity of the receiving paper.   5. The thermal transfer printer according to claim 4, wherein the information specifying the type of the receiving paper is a name of the receiving paper.   The thermal transfer printer according to claim 1, wherein the energy correction device corrects the energization time to the thermal head.   The thermal transfer printer according to claim 1, wherein the energy correction device corrects a voltage applied to a thermal head. The thermal diffusivity group of the receiving paper is
A first group of 5.0 × 10 ⁻³ cm ² / s or more,
A second group of 4.0 × 10 ⁻³ cm ² / s or more and less than 5.0 × 10 ⁻³ cm ² / s,
3.0 × ¹⁰ -3 ^cm 2 / s or more 4.0 × ¹⁰ -3 ^cm 2 / s less than a is a third group,
3.0 × ¹⁰ -3 ^cm 2 / thermal transfer printer according to any one of claims 3 to 9, characterized in that the fourth group is less than s. In a control method of a thermal transfer printer that transfers ink from a thermal transfer ink ribbon to a receiving paper with a thermal head,
While controlling the amount of energy applied to the thermal head based on the type and environmental temperature of the thermal transfer ink ribbon,
A control method for a thermal transfer printer, wherein the amount of energy applied to the thermal head is corrected based on the thermal diffusivity of the receiving paper used. The correction of the applied energy amount is as follows:
Identify the thermal diffusivity value of the receiving paper used,
12. The method for controlling a thermal transfer printer according to claim 11, wherein the input thermal diffusivity value of the receiving paper is performed based on a correction coefficient obtained based on a predetermined correction equation. The correction of the applied energy amount is as follows:
Identify which thermal diffusivity group of multiple thermal diffusivity groups grouped by the size of thermal diffusivity belongs to the receiving paper used,
13. The thermal transfer printer control method according to claim 12, wherein the control is performed based on a correction coefficient obtained based on the specified thermal diffusivity group of the receiving paper.

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