JPS60189468A - Copy printing device - Google Patents

Abstract

PURPOSE:To make the reproduction of color CRT picture possible, by a method wherein the L switch turning on and off a low potential and the H switch turning on and off a high potential are alternately connected to recording pointers, both adjacent switches being simultaneously turned ON and transfer is carried out. CONSTITUTION:For the recording head, a switch 50 on positive side and a switch 51 on negative side to a power source 8 are alternately used and connected to each electrode of H1-Hm and L1-Lm. By simultaneously turning ON the L switch of low potential and the H switch of high potential, the resistant layer is applied with current, heated and transfer is carried out on the paper to be transferred to form a picture element. These picture elements are divided into N groups represented by NXJ+1,NXJ+2,...NXJ+N (where J=0, 2, 3..., N is an odd number of 3 and more as the order starts from the first place) and they are formed by each group. Thus, high speed, medium tone recording and further full color recording can be obtained with high reliability.

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to a recording method for a printing device.

[Prior art]

Currently, there is an electrically conductive thermal transfer recording method as a method that allows multilevel recording and color printing. This method will be explained using FIGS. 1 and 2. FIG. 1 shows several examples of structures of ink films for electrically conductive thermal transfer recording. 1
is a melting lake layer, which is a layer in which pigment or pigment and dye are dispersed in wax, and has the property of melting at about 60°C.

2 is a resin film or capacitor paper using PBT or the like, and in the case of (a), this layer serves as the support for this film. 3 is a layer in which fine carbon powder is dispersed in resin, and is electrically conductive (hereinafter, 3 is referred to as a resistance layer). 4 is a conductive layer like 3, but in the case of (1)) and (e), this layer becomes the film support layer.

5 is a heat-resistant resin layer which is a color prevention layer. Printing is performed by passing an electric current through the resistance layer of these films and generating Joule heat, which melts the ink layer and transfers it to the paper to be transferred.

Each film structure shown in FIG. 1 has its own characteristics, but these will not be mentioned in this specification. Figure 2 shows the principle of multilevel recording. (a) shows a cross section. Figure 2 (
An example of the ink film 19 having the structure a) is shown. 10 is a transfer paper. Using the recording needle 6 and the cooperative electrode 7, the power source 8
When the switch 9 is wired and the switch 9 is closed, the current becomes 11.
flows into the resistance layer 3. The diagram showing (a) from above is ('
b). The current 110 distribution is shown. Since Joule heat is proportional to the square of the current density, the temperature distribution is (a)
It will be as shown in. Depending on the time the switch 9 is closed, a difference in temperature distribution occurs as shown in 12.13. 12 is an example in which the closed time is short and the amount of heat generated is small. T
m14 is the melting temperature of the ink, and in a temperature range higher than Tm, the ink melts and is transferred to the transfer paper 10. 15.1 respectively corresponding to the temperature distribution of 12.13
As shown in 6, the area of the transferred ink changes. Multivalue recording becomes possible by changing the time during which the current flows in this manner. The next important thing is high speed recording. To do this, it is essential to be able to record simultaneously with a large number of needles. FIG. 6 shows an example in which a plurality of recording needles are used.

19 is an ink film, and 7.6 is a common electrode and a recording needle as in FIG. 2(b). A simplified equivalent circuit of FIG. 3 is shown in FIG. 7.6 correspond to the common electrode and the recording needle, respectively. Each recording needle is connected to a power source 8 through a switch 9. 17, r'% is the equivalent resistance between the recording needle and the common electrode, and r2 is the equivalent resistance between adjacent recording needles. As is clear from FIG. 4, rl<<! Except for case 1, the value and direction of the current flowing through each recording needle changes depending on the open/closed state of each main switch, and the current cannot be controlled by that recording needle simply by opening/closing the switch corresponding to each recording needle. It's impossible. Furthermore, even if rt<<r2 is realized, it is very difficult to uniformly bring the common electrode and a large number of recording needles into electrical contact with the resistance layer as shown in FIG. To summarize the problems here, when putting into practical use a recording method using a large number of recording needles using the ink film with the resistive layer mentioned above, the most important thing that must be solved is electrical contact. To achieve even more uniform recording without mistakes, as shown in FIG. 2, recording is performed simultaneously using a plurality of recording needles.

〔the purpose〕

The invention is intended to solve the above-mentioned problems, and its purpose is to provide a highly reliable and low-cost printing device that is capable of high-speed halftone recording and full-color recording.

〔overview〕

The printing device of the present invention has a recording head composed of recording needles arranged in a row, and an L switch that opens and closes a low potential and an H switch that opens and closes a high potential are connected to the recording needle. By simultaneously closing the adjacent L switch and H switch, the resistive layer is energized to generate heat, melting the melting ink layer and transferring it to the transfer paper to form an image. In the photocopying device, the pixels are arranged in order starting from the end: NXJ-1-1, NXJ+2.・・・・・・N×
J ten N (, r is 0, 2.3...) (N,
It is characterized in that it is divided into N groups (an odd number of 3 or more), and pixels are formed for each group.

〔Example〕

Hereinafter, the present invention will be described in detail based on examples.

FIG. 5 shows a recording head 22 used in the present invention. The material of the electrode substrate 20 is preferably ceramic from the viewpoint of reliability such as heat resistance and durability, but inexpensive materials such as glass epoxy can also be used depending on the purpose. 2
1 is a recording needle, and there are multiple recording needles.The number of recording needles is:
It varies depending on the signal to be recorded, but the recording of the TV screen is shown in Figure 1.
2 requires about 500 changes. FIG. 6 shows a method of contacting the recording head 22 and the ink film 19 according to the present invention.

The main roller 30 is made of an elastic material such as rubber, and the transfer paper 10 is wound around the main roller 30 and fixed with a fixing jig 62. The ink film 226- is stored in a roll at 63 and wound onto the take-up roll 34 along the direction of the arrow. 35 and 66 are ink film transport rollers. The end portion 23 of the recording head 22 is pressed onto the main collar with a spring 37 using a fulcrum 58. By pressing the recording head having the structure shown in FIG. 5 against the ink film in the manner shown in FIG. 6, the recording needle and the resistive layer are completely electrically connected. As is clear from FIGS. 5 and 6, the only recording electrode is the recording needle, which makes it possible to bring the recording needle into contact with the resistance layer in an ideal manner. Furthermore, since the recording needle and electrode substrate are integrated, problems such as breakage of the recording needle do not occur, and reliability is significantly improved. Next, a method for recording and a method for performing gradation recording using a recording head having such ideal contact properties will be described.

FIG. 7(a) shows how to flow the K current, 40.41 is the part where the recording needle is in contact with the resistance layer, and 42 is the current. The voltages were applied such that 40 was negative and 41 was positive. By changing the energization time in the same manner as in FIG. 9, the temperature distribution changes as shown in 43.44. 4
6 is a case where the energization time is short, and 44 is a case where it is long.

As a result, the ink transferred becomes 45.46, respectively, and area gradation can be added. FIG. 8 shows a method for recording all adjacent periods. Use the plus side switch 50 and the minus side switch 51 alternately as shown in the figure for the electric conductor 8, and set H1 to Hm.
and L1~'LmO are connected to the needle electrodes. The number of needle electrodes is...2m (m is a positive integer), and the recording pixels are:
It becomes 2m-1 ke.

After that, turn the negative switch (low potential switch) to L.
Switch, the positive side switch (high potential switch) is the H switch, the needle electrode connected to the negative terminal is the Lt pole,
The positive side is called the H electrode. When focusing on H1, a pixel is formed between H1 and L1 by passing a current between H1 and 10, and a pixel is formed between H1 and 1.2. In this way, pixels can be formed between all the L electrodes and H electrodes.

FIG. 9 shows an equivalent circuit when focusing on the k-th L electrode. A resistor 52 is inserted between all the H electrodes,
Depending on how the H switch is turned on, the way the electric current flows will change. This is similar to the conventional example shown in FIG. 4 and cannot be used. As a way to solve this problem, a patent application filed in 1864
I applied for 95th grade. The present invention further improves the above-mentioned patent application to eliminate the above-mentioned drawbacks, and is made into a film. First, the above patent application will be described, and then the improvements of the present invention will be described.

The basic principle of patent application No. 58-186495 is shown in FIG. (a) shows how current flows in the resistance layer, and t,'b) is its equivalent circuit. [(The potential of the pole 41 and the L electrode 40 is determined depending on the open/closed state of the switch as shown in FIG. In the open/closed state, current flows as 54 and 55. At this time, 5
Currents such as 6 and 57 cannot exist in principle. Therefore, the equivalent resistance of this circuit is 5 as shown in figure (b).
5, and 9- The current that flows is always determined only by the resistance between adjacent electrodes. The equivalent circuit of (b) is 54 and 55
This holds true only when the direction of the current (arrow) is opposite. To further explain this, in order to realize the equivalent circuit shown in Figure 9(b), the time during which the H switch and L switch are closed is must be the same. For example, if the kth H switch is closed, the -1-1st H switch is closed, and the k-1-2nd L switch is open, a current of 57 is generated, which does not hold true. In other words, 6 in Figure 11(a)
It is necessary to use a double-opening switch like 62 instead of a single-opening switch like 0 and 61, and to open and close the adjacent H switch and L switch with the same signal as shown in FIG. 11(b). In FIG. 11(b), 63 is Ll and H1, 64 is Hl and L2, and 65 is an opening/closing signal for the switch of -2 and H2. 63, 64° and 65 must have different closed signal sections.

When the recording method shown in FIG. 9 is used, one-fifth of all the pixels in one column can be formed at the same time. To form one row of pixels, 3
Record the times at different times. This is shown in -10- Figure 12. By opening and closing each of the switches (a), (1)), and (C), a current 70 sequentially flows through the equivalent resistance 53 between adjacent electrode needles, forming one column of all pixels. Next, we will discuss the drawbacks of this method. Figure 13 (a
) shows a diagram in which only the closed switch in FIG. 12(a) is extracted. FIG. 15(a) shows an energized state in which all five pixels shown here are formed. FIG. 15(b) shows the middle one of the three cases where no formation is made. 2
The switch marked 00 is in the open state. At this time, current flows through two circuits 201 and 202. 201 is 7
202 is slightly smaller than 0, and 202 is about 8 to 10 inches smaller than 201. This crosstalk can be ignored for the most part when binary printing is performed, but when halftone printing is performed, it becomes a serious problem depending on the number of halftones. The less this crosstalk, the better. The present invention reduces this problem, and the present invention is generalized including the above patent application.

In the present invention, pixels are formed in one group for every three pixels in the above-mentioned patent application, whereas pixels are formed in one group for every N pixels, that is, the pixels are formed in order from the end to N is 0
, 1゜2.3.4..., divided into N groups (N is an odd number of 3 or more), forming pixels for each group, and repeating this N times. .

By setting N to an odd number of 3 or more, it has the feature that multiple pixels can be formed at the same time, which is the greatest advantage of the above applied patent.
Furthermore, by increasing N, the above-mentioned drawback of crosstalk can be reduced. However, when N increases, the number of pixels that can be formed simultaneously decreases. Actually N
When determining , the optimum value can be selected based on the above two points.

FIG. 14(a) shows the opening and closing of the switch when N=5, and FIG. 14(b) shows the opening and closing of the switch when N=7. This corresponds to FIG. 12(a). Of these, FIG. 15(a) shows the switches in the closed state. 15th
Figure (b) shows the case where the middle switch is in the open state. The current flow at this time is the same as in FIG. 15 (tl), but the crosstalk current 204 is 2 to 4 with N=5.
%, N=7, it becomes about 1 to 2 inches, which decreases significantly. The larger N is, the more the crossstreak is reduced, and the gradation ys ability for printing intermediate tones is improved.

Next, a specific example will be described.

[Example 1] This is the case when N=5.

A recording head shown in FIG. 16 was used. This shows the tip of the recording head. 'Ni-' on the ceramic substrate 101
0r102 and 0r103 are deposited, an electrode is formed by photoetching, and N1-W- is selectively deposited on this electrode.
``P's unmarked, deplated.The number of recording needles is 1st.
As shown in Figure 4, there are 320 L electrodes and 320 H electric persimmons each (L1~L+20.T!11~ in the arrangement shown in Figure 17) (3
20), and the number of pixels formed by these recording needles is 659.

(P1 to P639 in Figure 17) Recording needle pitch (P) 1
05 is 200 μm. Using this recording head, a conveyance system for transfer paper and ink film was constructed as shown in FIG. The ink film is wound into a roll, and the inks are colored separately as shown in FIG. 111 is yellow, 112 is magenta, and 113 is cyan. 110 is a resistance layer. FIG. 19 shows a block diagram of the circuit of the printing apparatus of the present invention. One column of image signals is input to 600, passes through a switch (5014 or 502), and is sent to line memory A3.
05 or stored in the line memory B 504 at the address from the write address generator 505. This image signal is read from the address of the read address generator 506, inputted to the digital comparator 607,
It is compared with the reference signal 621 from the gradation reference signal generator 520, and the result is input to the shift register 608 and transferred at the shift clock 405. , is sent to a temporary memory 509 by a latch clock 406, and distributed by a distributor 510 to an H switch or an L switch according to a recording order selection signal 407. This output signal is connected to each recording needle. Although the overall signal flow has been described above, it will be explained in more detail below.

FIG. 25 shows the flow of people in the image signal.

-14- 404 is a signal that controls the switch 501 and the switch 502, and is inverted at the cycle of the line cycle TL410. The input image 1 signal 400 is composed of a 640-pixel signal and is sent at TW4120 times. The input image signal 40011-t is stored in either line memory A or line memory B according to the address of the write address generator depending on the open/closed state of switch 601 or 602. At this time, the output image signal 401 is read out from the other line memory according to the address of the read address generator. Signals on the data lines of line memories A and B are shown at 402 and 405. 400 to 406 are one of the parallel signals. Here, the write address and read address will be explained.

Table 1 shows 640 addresses using a1 to a128 and b to bs'l. Table 2 is the write address order. The input image signal is a signal sequentially connected from the end, and is stored in line memory A or line memory B in the order shown in Table 2. In other words, if you number the input image signal from 1 to 640, number 1 is address 0. number 2 is address 12B, and number 5 is address 25.
Numbers 6...659 are stored at address 511, and the last number 640 is stored at address 659. The read address changes in order from al to a127 for each block column from 61 to 65, and furthermore, in this embodiment, the image signal is
16 for each block due to 4 focus and 16 gradation signals
Read times. The division into five blocks b1 to b5 as described above corresponds to the most important elements of the present invention on the circuit. When recording and forming pixels, the pixels are recorded in order from the end to 5J+1.5. T+2...5. T-4-5
(, r is 0, 1.2, . . . , 128), so that the image signals are recorded in five groups, so the writing and reading addresses are used to convert the arrangement of the image signals. In this embodiment, the data is divided into five blocks using the inset addresses, but it is also possible to perform reading while dividing the data into blocks.

Light 1 Table 2 -17- The read image signal 401 is sent to the digital comparator 30
7 and is compared with the reference signal 321 from the gradation reference signal generator 520, and converted into a comparison binary signal 321 of 0/1 depending on the magnitude. The image signal is a1 with 1 block.
~a128 is read 16 times, but the reference signal is 1
It changes from 0 to 15 once per round. In other words, the number of comparisons is 128×16 times. This time is the period of TRA 415 of the output image signal 401 in FIG. 25. TRA is one-fifth of the line period TL. The compared binary multiple number 521 is sent to the shift register 508. 20th
The figure shows the circuit after the shift register. Figure 20 shows
(2) The basic system is to operate the switches and L switches five times each. In this embodiment, 64 blocks are connected in cascade or in parallel. 500 and 501 are D
500 is used for a shift register, and 501 is used for temporary storage. 80K each
A signal is read at the rising edge of (shift clock) 405 and LOK (latch clock) 406.

-18- SOK is the period of minimum change in read address TRA/
(128X16) and 1. OK, TRA/1
This is a 60-cycle clock. The above will be explained using FIG. 24. The reference signal 521 is a 4-bit signal ROKO to ROK3. ROKO is the least significant bit and ROK5 is the most significant bit.

During the TRA period, it changes from 0 to 15 at the cycle of TRA414, and this is repeated. During the period of TRa, the image signal is 1
Blocks al to a128 are output and compared. Period r1 of latch clock LOK4Q6. T Ra
Yes, the 4050 cycles of the shift clock 80 match the output cycle of the image signal. Returning to the explanation of FIG. 20. Comparison binary signal 321iI, 1st stage DA5
30 terminal, and is sequentially shifted to the next stage using the shift clock 80 at 405. This signal is the latch clock L
At OK40tS, all the data are transferred to the subsequent one-time memory flipflop 501 and held for only the period of TRA414.

The image fg@ that has passed through the digital comparator 607 has been subjected to pulse width conversion at this point. This signal is called a pulse width image signal 540. This signal is selected by the recording order selection signal 407 and opens and closes the L switch 504 and the ■ switch 505. 502 is an AND circuit, and 505 is an OR circuit. Here, the PD531 and the ND532 are connected between the front and rear stages. VH556 is a high potential, V
Llli is a low potential voltage. The L switch and the ■ switch will be explained using FIGS. 21 and 22.

The L switch and the H switch 9 have the configuration shown in FIG. 21, open and close the switch 522 according to the opening/closing control signal 510, and output the potential of the power supply line 520 to the output terminal 521. FIG. 22(a) shows an L switch. 506 is NFN Run Sister. The low potential 511 is measured by the opening/closing side @signal 510, and the low potential is output to 512. FIG. 22(b) shows an H switch. 507 is PN
P) Run sister 508 is an inverting circuit. High potential 5
14 to 515.

FIG. 25 shows recording selection signals 407801 to B06.

801 lags behind signal 404 for switching between line memory A and line memory B by approximately TRA415. This is because the opening/closing control signal 510 passes through the shift register 405 and is delayed by TRA relative to the output image signal read out from line memory A or line memory B. Each of the recording order selection signals 801 to 806 sequentially opens and closes the L switch and the ■ switch by a pulse width corresponding to the pulse width image signal 540 according to the write address order shown in Table 2.

A television screen was printed using the recording head, ink film transport system, and drive circuit described above.

The television image signal was converted into an analog-to-digital signal, stored in a 640 x 480 x 3-color frame memory, and then inputted into a 500 in FIG. 19.

- a3 m seconds to form a column of pixels, i.e. TTI, = a3 m
seconds, TRA = 1.66 msec, full screen 480 columns'
ii. Printing was performed in 4 seconds each in five colors: yellow, cyan, and agenta. The printed image 11), the CRT screen and 21- had almost the same image quality. FIG. 26 shows a part of the printed image. Arrow 600 is the center of the recording needle. pixel 60
1 is formed between the recording needles.

Furthermore, since the ink effluent and the transfer paper were continuously moved during printing, pixels were formed on the diagonal line 601. This resulted in an image without the scanning lines seen on a CRT.

[Example 2] This is the case when N=7.

The overall configuration is almost the same as that of the first embodiment. However, N=
7, the number of recording needles, the number of image signals, etc. are different. Only the most important points regarding the structure are listed below.

The number of recording needles is 630 in total, 315 each for L electrodes and H electrodes.
The number of pixels is 629. The write address order is
It is shown in Tables 3 and 4.

22-Table 5 Table 4 Table 3 represents 650 addresses using a1 to a90 and b1 to b7. Table 4 shows the order of write address generation. Divide into 7 groups. Correspondingly, the recording order selection signals also become 801 to 80B.

It is shown in FIG.

With the above configuration, printing of a television screen was performed.

The TV image signal is 640 x 480 x 3 as in Example 1.
Once stored in the color frame memory.

Line memory A or line memory Bl'lL,
Only 650 fractions out of 640 in one column are stored.

Ta. - The pixel formation time of the column is a3m seconds, TL=11L3
Imprinting was performed at a speed of 1.19 msec, TRA=1.19 msec.

The printed image has a high quality with excellent reproducibility.

〔effect〕

As described above, the present invention makes it possible to copy a color CRT screen, enables high-speed recording, has a simple recording head structure, and uses a pair of L! Gradation recording using polar and H electrodes,
Furthermore, since the load on the power supply and drive circuit is reduced due to low recording energy, a complete color image printing apparatus can be realized at extremely low cost.

[Brief explanation of drawings]

FIGS. 1(a) to 1(c) are diagrams showing cross sections of the ink film used in the present invention. FIGS. 2A to 2C are diagrams showing a method of performing area gradation recording using an ink film and a conventional recording head. 3 and 4 are diagrams showing a conventional recording method and its equivalent circuit. FIGS. 5(a) to 5(c) are diagrams showing the tip portion of the recording head used in the present invention. FIG. 6 is a diagram showing the configuration of a conveyance system for the ink film and transfer paper used in the present invention. FIGS. 7(a) to 7(c) are diagrams showing a method of performing area gradation recording using the recording head used in the present invention. FIG. 8 is a diagram showing the basic switch connections to each recording needle of the present invention. -25- FIG. 9 is a Fuhi diagram showing an equivalent resistance circuit between each recording needle. FIGS. 10(a) and 10(b) are diagrams showing opening/closing and equivalent circuits of a conventional switch. FIGS. 11(a) and 11(b) are diagrams showing one method of controlling the opening and closing of the switch. FIGS. 12(a) to 12(c) are diagrams showing the opening/closing sequence of a conventional switch. FIGS. 13(a)*(b) are diagrams showing the drawbacks in opening and closing the conventional switch. FIGS. 14(a) and 14(b) are diagrams showing the basic switch of the present invention when it is opened and closed. Figures 1s (a) and 1s (b) are diagrams showing the crosstalk current of the present invention. FIGS. 16 and 17 are diagrams showing the tip of the recording head used in the present invention. FIG. 18 is a diagram of an ink film used in the present invention. FIG. 19 is a block diagram of the circuit of the printing apparatus of the present invention. -26- Figure 20 fi, 1 (shows the basic units of switch and L switch operation. Figures 21 and 22 (a) and (b) show the configuration of the H switch and L switch. FIG. 25, FIG. 24, FIG. 25, and FIG. 27 are diagrams showing operation signals of the present invention. FIG. 26 is a diagram showing an arrangement of forming pixels of the present invention. 3...Resistance 1...Melting ink layer 19...Ink film 22...Recording head 21...Recording needles 51 and 50
4...L switch 5o and 505...H switch and above Applicant Suwa Seikodai Co., Ltd. Agent Patent Attorney Tsutomu Mogami -27- Figure 1 Figure 5 J4 Figure 6 Figure 7 57 Figure 10 Figure 72 (α) Figure 15 1 Figure 1b Figure 17 Figure 20 515 Figure 22 Procedural amendments) llIllIN6Q Mokame 1, Indication of the case Patent application No. 44572 of 1982 2, Name stamp of the invention Copying device 3, person making the amendment 5, Procedural amendment to increase the number of inventions due to the amendment (voluntary) 1. Amend the phrase "rake layer" in the ninth line from the bottom of page 2 of the specification to "ink layer." 2. On the 7th line from the bottom of page 3 of the specification, amend "(a)" to "(C)". (v) On page 5, line 6 of the specification, the phrase ``In Figure 2,'' is amended to read ``Secondly,''. 4. On page 6 of the specification, line 6 from the bottom, the phrase ``Recording line 12 is'' should be amended to ``For recording purposes.'' 5. The negative bottom line of specification 7, where it says "Figure 9," is amended to "Figure 2."& ``Toshi 1'' on the 5th line from the bottom of the specification 8 is corrected to ``and I, IJ.'' 2-2 The ``L'' on the 2nd line of page 9 of the specification is corrected to [LkJ. a. On page 10 of the specification, line 7, it says ``stop switch.'' Correct it to ``and L switch.'' 9. On the third line from the bottom of page 10 of the specification, "Figure 9" is amended to "Figure 10." 10. Amend "Fig. 14" in line 11 of the specification 13 to "Fig. 17." 11, Specification page 16, line 6, ``61-6 s@J is corrected to rb1-b5JK. [a127J is corrected to 1' a 12 a J. 12, Specification 18, negative 4 lines 1 & Specification 18 Negative 5th line 3- 1 with a1~a128'!
+28). 14. Specification 18 Negative line 11 Specification page 19 Line 14 Delete "321J." 15. Figure 2, Figure 8, Figure 9, Figure 10, Figure 11,
Figures 12, 13, 14, and 15 are corrected and attached as separate sheets. 4- Figure 8 Figure 9 435 (α) Figure 14-

Claims (2)

[Claims] (1) An ink film consisting of at least a resistive layer and a molten ink layer is used, a recording head is composed of a plurality of recording needles arranged in a line, and a switch for opening and closing a low potential, an L switch for opening and closing a high potential, and a high potential H to open and close
Switches are alternately connected to the recording needles, and by simultaneously closing adjacent L switches and H switches, the resistive layer is energized to generate heat, melting the molten ink layer and applying it to the transfer paper. In a printing device that transfers pixels to form pixels, NXJ-1-
1, NXJ+2.・-・・・-NX, r-1-N(,
T is 0.1, 2.3...) IJ is an odd number of 3 or more), and pixels are formed for each group. . (2) The printing apparatus according to claim 1, wherein the area of the pixel is changed by changing the time during which the resistive layer is energized.