JPH02208061A - Thick film type thermal head - Google Patents

Abstract

PURPOSE:To increase an interval between adjacent ones of a plurality of resistor forming openings in a resist layer formed on the surface of an insulating board and to form a plurality of heat generating resistors at a high density by thick film technique by disposing adjacent ones of a plurality of heat generating resistors separately in a sub scanning direction. CONSTITUTION:An insulating board 2 formed with both electrodes 3, 4 is coated with photoresist, covered with a mask, not shown, exposed and developed. Thus, the end 3b1 of a common electrode connecting part 3b and individual electrode ends 4a are disposed therein, and a resist layer L having a plurality of resistor forming openings 15 arranged in a zigzag manner along a main scanning direction X is formed. Since the width of the adjacent openings 15 along a sub scanning direction Y is set to the length 2l of two scanning lines, the interval between the openings 15 is increased. Accordingly, the part is scarcely peeled, and a limit in high density of printing dots is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION A0 Object of the Invention (1) Industrial Application Field The present invention relates to a thick-film thermal head used in a thermal recording device such as a thermal recording facsimile machine or a thermal printer. .

(2) Conventional Technology Thin-film or thick-film thermal heads have been widely used in thermal recording devices such as facsimile machines and thermal printers using thermal recording methods.

The thin-film thermal head uses thin-film technology such as vapor deposition or sputtering to form a plurality of individual heating resistors on an insulating substrate along the main scanning direction, and prints uniform, high-density printed dots. However, the disadvantage is that the manufacturing equipment becomes large-sized and the cost becomes high. In addition, the thick-film thermal head usually uses thick-film technology such as screen printing to form a band-shaped heating resistor along the main scanning direction on an insulating substrate, and is low in cost. ,
Since it is necessary to form the electrodes at twice the density of the printed dots, there is a drawback that it is difficult to increase the density of the printed dots.

(3) Problems to be Solved by the Invention In view of the above-mentioned circumstances, it is an object of the present invention to provide a thermal head that can be manufactured using thick film technology with inexpensive manufacturing equipment and that can provide high-density printed dots. .

B0 Structure of the Invention (1) Means for Solving the Problems In order to solve the above problems, the present invention includes a common electrode main body part in the form of a band extending along the main scanning direction and a comb-like shape extending from the main body part. a common electrode that extends in the sub-scanning direction and has a plurality of common electrode connection parts whose tips are arranged along the main scanning direction; and an individual electrode that is arranged opposite to each tip of the plurality of common electrode connection parts. A plurality of individual electrodes each having an electrode tip, a plurality of predetermined shapes such that the tip of each common electrode connection portion and the individual electrode tip disposed opposite thereto are arranged in each resistor forming opening. The resist layer is formed from an insulating substrate having a resist layer formed with the resistor formation openings and unsintered resistors formed in each of the plurality of resistor formation openings. is removed and the unsintered resistor is fired to form a plurality of heat generating resistors on the insulating substrate, the thick film type thermal head comprising a plurality of heat generating resistors arranged adjacently among the plurality of heat generating resistors. The heat-generating resistors are placed apart in the sub-scanning direction, and the heat-generating resistors selected every N along the main-scanning direction
By configuring a group, the plurality of heating resistors are N+1.
When divided into groups, the heating resistors belonging to the same group are arranged in a straight line along the main scanning direction.

(2) Function The thick-film thermal head of the present invention arranges adjacent heat generating resistors among the plurality of heat generating resistors to be spaced apart in the sub-scanning direction, so that the heat generating resistors are spaced apart from each other in the sub-scanning direction. When a predetermined number of heating resistors are arranged in a row, the distance between adjacent heating resistors along the main scanning direction can be increased compared to when the heating resistors are arranged in a line along the main scanning direction. .

Therefore, when forming the plurality of heating resistors, it is possible to increase the distance between the plurality of resistor forming openings in the resist layer formed on the surface of the insulating substrate.

When the distance between adjacent heating resistor forming openings is widened in this way, there is no possibility that the openings will peel off from the surface of the insulating substrate.

(3) Example Hereinafter, an example of a thermal head manufactured using the thick film technology of the present invention will be described with reference to FIGS. 1 to 10.

FIG. 1 is an overall explanatory diagram of an embodiment of the thermal head of the present invention, FIG. 2 is a perspective view of the main parts of the same embodiment, FIG. 3 is an enlarged view of the part shown by the arrow ■ in FIG. The figure is a view from the ■ arrow in Figure 3.
Figure 4B is a sectional view taken along line IVBIVB of Figure 4A, and Figure 5A~
FIG. 9B is an explanatory diagram of a method of manufacturing the main parts of the same embodiment, and FIG. 1O is a diagram showing an electric circuit for driving the same embodiment.

As shown in FIG. 1, a thick film type thermal head H for performing thermal recording on a thermal recording paper P conveyed along the outer periphery of a platen roll R is provided with a support plate 1. On the surface of this support plate l, an insulating substrate 2 consisting of an aluminum substrate main body 2a and a glaze heat storage layer 2b formed on the surface thereof is pasted with adhesive on the right side in FIG. ing.

On the surface of the heat storage layer 2b, as shown in FIGS. 3 and 4A, a strip-shaped common electrode main body portion 3 extending along the main scanning direction
a and a plurality of common electrode connecting portions 3b extending from the main body portion 3a in a comb-like shape in the sub-scanning direction Y, and having a tip portion 3b+ disposed along the main-scanning direction X. The common electrode connecting portions 3b are composed of two types, long ones and short ones, and they are arranged alternately along the main scanning direction X.

Further, on the surface of the heat storage layer 2b, an individual electrode 4 having an individual electrode tip portion 4a disposed facing each tip portion 3b of the plurality of common electrode connecting portions 3b at a predetermined interval is provided. A plurality of individual electrodes 4 are arranged along the direction
It is formed as.

The tip portion 3b of the plurality of common electrode connecting portions 3b.

Each of the individual electrode tip portions 4a includes a plurality of individual heating resistors 5+ arranged in a staggered manner along the main scanning direction X.
, 5z, . . . , 51. 4th A,
As shown in Figure 4B, the plurality of heating resistors 5. ,L,
The heating resistors 51, 51, and 51, which are adjacent to each other in...
... are shifted in the sub-scanning direction Y by a width 21 corresponding to two scanning lines.

Among the plurality of heat generating resistors 5+, 5g, . . . , the heat generating resistor 5. Odd-numbered heating resistors 53, 5s+..., 50... (k=1.2...) are selected from this resistor 51 every other time along the main scanning direction
) are arranged in a straight line along the main scanning direction X, and constitute a first group A of heating resistors. Also, in FIG. 4A, the heating resistor 5□ located second from the bottom and this resistor 5! from main scanning direction
Even-numbered heating resistors 5 are selected every other along
4.5&,...+52. +...(k=1.2.・
) are arranged in a straight line along the main scanning direction X, thereby forming the second group A! of heating resistors. is configured. Therefore, the heat generating resistors 5. belonging to the respective groups A, . ．． 5. ,...5zt1.
...;5! The columns +54+..., 5im+... are parallel to each other along the main scanning direction X and correspond to two scanning lines in the sub-scanning direction Y. They are placed far apart. Further, both the electrodes 3.4 and the heating resistor 5+
, 5i, . . . are covered with a wear-resistant layer 6 made of glaze.
illustration is omitted. ).

A printed wiring board 7 is attached to the surface of the support plate 1 on the left side in FIG. 1 with an adhesive, and external connection wiring 8 is formed on the surface of the printed wiring board 7. This external connection wiring 8 is connected to its input end side (the first
It is connected to a socket IO serving as a drive signal input terminal via a lead wire 9 passing through the printed wiring board 7 on the left side in the figure. A driving IC is disposed in a portion of the printed wiring board 7 near the insulating substrate 2, and this driving IC connects the bonding wires 11 and 12.
It is connected to the IC connection terminal 4b of the individual electrode 4 and the external connection wiring 8 by.

The 1G and bonding wires 11 and 12 are covered with a protective resin 13, and the protective resin 1
3 is protected by an aluminum cover 14.

The thick film type thermal head H is designated by the reference numeral 1 to
It is composed of a member indicated by 14 and the driving IC.

Next, a method of manufacturing the common electrode 3, individual electrodes 4, heating resistor 5, etc., which are the main parts of the thick film type thermal head H, will be explained with reference to FIGS. 5A to 9B.

First, as shown in FIGS. 5A and 5B, an electrode formation film is formed on the surface of the insulating substrate 2 by vector printing, and then long and short electrodes are alternately arranged along the main scanning direction X by photolithography. a common electrode 3 having a common electrode connection portion 3b; and an individual electrode tip portion 4a disposed facing the tip portion 3b+ of the common electrode connection portion 3b at a predetermined interval.
As shown in FIGS. 6A to 6C, a photoresist is applied to the surface of the insulating substrate 2 on which both the electrodes 3.4 are formed, and a mask (not shown) is covered. By exposing and developing this, each tip portion 3b of the common electrode connection portion 3b and each individual electrode tip portion 4a are arranged inside, and a plurality of pieces are arranged in a staggered manner along the main scanning direction X. Opening 1 for resistor formation
Form a resist layer having 5. In this embodiment, the deviation width of the adjacent resistor forming openings 15 along the sub-scanning direction Y is set to a length of two scanning lines, 2 mm. Therefore, the distance between adjacent resistor formation openings 15 becomes sufficiently large, making it difficult for that portion to peel off. Therefore, there is no restriction on increasing the density of printed dots due to the risk of peeling off.

Next, as shown in FIGS. 7A and 7B, the paste M for forming a resistor is printed in a band shape by screen printing, and the opening 15 for forming a resistor is filled with this base M.
As shown in Figures A and 8B, the resistor forming paste) M
After drying, the dried paste in the portion higher than the surface of the resist layer is removed by lapping, and the unsintered resistors 5a+, 5az, . . . are placed in the resistor forming opening 15.
Next, as shown in FIGS. 9A and 9B, the unsintered resistors 5a++5az+... are fired and the resist layer is removed by burning, thereby connecting the common electrode to the surface of the insulating substrate 2. The tip portion 3b of the portion 3b and the tip portion 4a of the individual electrodes are connected to each other, and the plurality of heating resistors 51, 5□, . . . arranged in a staggered manner along the main scanning direction X are formed. Next, the picture electrode 3-
14 and heating resistor 51,5! , . . . are coated with a wear-resistant layer 6 made of glaze to complete the main part of the thick film type thermal head H shown in FIGS. 4A and 4B.

Next, the operation of this embodiment having the above configuration will be explained with reference to FIG. 10 as well.

FIG. 10 is a diagram showing an electric circuit for driving this embodiment, in which a plurality of heating resistors 51, 5! . . , 57, the image data al+82+ . . . a is input to the -dan register 16. Next, in FIGS. 4A and 4B, the second group of heating resistors AH1, that is, the even-numbered heating resistors 5!, comes into contact first with the thermal recording paper P that is fed from left to right along the sub-scanning direction Y! ,5-,...,5□0
．． The column . . . shows the registers 16 . An image data signal from the printer is inputted via the print pulse gate 17. In addition, a first group AI of heating resistors that will come into contact with the thermal recording paper P later, that is, odd-numbered heating resistors 51, 53
．． ...+5111-1+..., the image data signal from the register 16 is input to the shift register 1.
8 and a print pulse gate 17.

This shift register 18 has a width of 2 for the thermal recording paper P of 2 scanning lines! The image data signal is delayed by the time it takes to travel. Therefore, one scanning line portion to be printed on the thermal recording paper P corresponds to the even-numbered heating resistors 51, 54 . When it comes into contact with the row of . ,53 ,...+52
When the -++, . . . column is reached, printing is performed on the remaining half of the column.

Although one embodiment of the thermal head using the thick film technology according to the present invention has been described in detail above, the present invention is not limited to the above-mentioned embodiment, and may deviate from the present invention as set forth in the claims. It is possible to make various small design changes without moving.

For example, in this embodiment, a plurality of heating resistors 5. .

5□,...,5. In the above example, the heating resistors 5+, By configuring one group of heat generating resistors 5z, ..., 5n selected every second along the main scanning direction X, the plurality of heat generating resistors are aligned in the main scanning direction
It is also possible to divide it into three groups arranged in a straight line along, and it is also possible to further divide it into four or more groups.

Further, in this embodiment, an example is shown in which adjacent heating resistors are shifted by a distance 21 corresponding to two scanning lines in the sub-scanning direction Y, but the value of the shifting width can also be set arbitrarily. In that case, the delay time of the signal output from the shift register 18 may be changed as appropriate.

C8 Effects of the Invention According to the above-described thick film thermal head of the present invention, the heat generating resistors arranged adjacently among the plurality of heat generating resistors are arranged apart from each other in the sub-scanning direction. Among the plurality of resistor forming openings in the resist layer formed on the surface of the insulating substrate when forming the resistor, the distance between adjacent openings can be increased. Therefore, the resist layer located between the adjacent openings does not peel off from the surface of the insulating substrate. Therefore, the plurality of heat generating resistors can be formed in high density using the inexpensive thick film technology of manufacturing equipment. Therefore, a thermal head with high printing dot density can be obtained.

[Brief explanation of the drawing]

1 to 1O are drawings showing an embodiment of the thick film type thermal head of the present invention, FIG. 1 is an overall explanatory view of the same thick film type thermal head, and FIG. 2 is a perspective view of the main parts thereof. , Fig. 3 is an enlarged view of the part shown by the arrow ■ in Fig. 2, and Fig. 4A is an enlarged view of the part I in Fig. 3.
FIG. 4B is a sectional view taken along the line rVB-rVB of FIG. 4A, and FIGS. 5A to 9B are explanatory diagrams of a method for manufacturing the main parts of the same thick-film thermal head, and FIGS. 5A, 6A, 7A, 8
Figures A and 9A are partial plan views of the main parts of the thermal head corresponding to each manufacturing process, and Figures 5B, 6B, 7B, and 8
Figures B and 9B are the VB-VB line in Figure 5A, the VIB-VIB line in Figure 6A, and ■B-■B in Figure 7A, respectively.
line, ■B-■B line in Figure 8A, and IXB- in Figure 9A.
A sectional view taken along line IXB, FIG. 6C is VIC- in FIG. 6A.
FIG. 10, a sectional view taken along the VIC line, is a diagram showing an electric circuit for driving the same thick film type thermal head. 3... Common electrode, 3a... Common electrode main body, 3b.
...Common electrode connection part, 3b, ... Tip part of common electrode connection part, 4... Individual electrode, 4a... Tip part of individual electrode,
51-5. ...heating resistor, (5+, 5i, ...,
5□. +), (S□, 54...., 5im)...N
(N=2) Heating resistors selected every other time, 5a, ~5a
I... Unsintered resistor, 15... Opening for resistor formation, A. , AH... 1 group of heating resistors, H... thick film thermal head, L... resist layer, X... main scanning direction,
Y...Sub-scanning direction, Fig. 2, 5, 8th prisoner, 5B @ Fig. 7A, Fig. 7B, Fig. 6A, W'' Fig. 6B, Fig. 6C, Fig. 8A, Fig. 8B, Fig. 9A, Fig. 9B, a5...・・・・・・an-r n

Claims (1)

[Claims] A strip-shaped common electrode main body (3a) extending along the main scanning direction (X) and a comb-like shape extending from the main body (3a) in the sub-scanning direction (Y), and a tip end thereof. A common electrode (3) in which the portion (3b_1) has a plurality of common electrode connection portions (3b) arranged along the main scanning direction (X), and a tip portion of each of the plurality of common electrode connection portions (3b). (3b_1) and a plurality of individual electrodes (4) each having an individual electrode tip (4a) disposed opposite to the tip (3b_1) of each of the common electrode connecting portions (3b) and the tip (3b_1) disposed opposite thereto. The tips of the individual electrodes (4a) are the openings (15) for forming each resistor.
a resist layer (L) in which a plurality of resistor formation openings (15) of a predetermined shape are formed so that the resistor formation openings (15) are formed in the resistor formation openings (15); unsintered resistors (5a_1, 5a_2,..., 5
an insulating substrate (2) with a_n) disposed on the surface (2a);
Then, the resist layer (L) is removed and the unsintered resistors (5a_1, 5a_2, ..., 5a_n) are fired to form a plurality of heat generating resistors (5) on the insulating substrate (2).
_1, 5_2, ..., 5_n) are formed on the thick film type thermal head, wherein the plurality of heating resistors (5_1, 5_2, ..., 5_n) are formed.
The heating resistors arranged next to each other in n) are spaced apart in the sub-scanning direction (Y), and
The plurality of heating resistors (5_1, 5
_2, ..., 5_n) are divided into N+1 groups, and heating resistors belonging to the same group are arranged in a straight line along the main scanning direction (X).