JP2001038946A - Thermal printer for high image quality printing and thermal head for high image quality printing used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal head for high image quality printing, capable of preventing generation of printing irregularity caused by the head structure, without measuring printing density irregularity of each dot. SOLUTION: A heat generator 2 is mounted on a glass substrate 1, and a head driving IC 6 is mounted on a glass epoxy substrate 3. The two substrates are mounted side by side on a head supporting plate by an adhesive. The heat generator 2 and the head driving IC 6 are connected electrically by a pattern on the glass substrate 1 and a bonding wire. The bonding wire and the head driving IC 6 are covered with an protected by a silicone rubber 7. A heat discharging opening 9 is provided in the head supporting plate 5 corresponding to the rear surface of the heat generator 2. Since the adhesive is not applied on the part of the head discharging opening 9, nothing is in contact with the glass substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal printer for high-quality printing and a thermal head for high-quality printing used therewith, and more particularly to a thermal head used for performing high-quality printing requiring gradation expression in the thermal printer. .

[0002]

2. Description of the Related Art Conventionally, in a thermal printer, when performing high-quality printing requiring gradation expression, a substrate on which a heating element of a head is mounted and a support plate of the substrate are bonded with an adhesive. The formed thermal head is used.

[0003] In this case, since the heat radiation characteristics differ inside the head due to the unevenness of the amount of adhesive applied and the shape of the head substrate support plate, if the same energy is applied to each heating element, printing is not performed at a uniform density. Print unevenness occurs.

In order to solve this problem, data printed with uniform energy is read by an image scanner, the variation in print density of each dot is measured, and the result is fed back to print data to perform uniform printing. ing.

[0005]

In the above-mentioned conventional thermal printer, printing unevenness occurs due to a structural factor of the head. To solve this problem, data printed with uniform energy is used. It must be read by an image scanner and the variation in print density of each dot must be measured.

Accordingly, an object of the present invention is to solve the above-mentioned problems and to prevent the occurrence of printing unevenness due to the structural cause of the head without measuring the variation in the printing density of each dot. An object of the present invention is to provide a thermal printer for high quality printing and a thermal head for high quality printing used therefor.

[0007]

According to the present invention, there is provided a thermal printer for high-quality printing using a thermal head formed by bonding a substrate on which a heating element is mounted and a support plate of the substrate with an adhesive. A high-quality printing thermal printer for performing high-quality printing requiring expression, wherein the thermal head has a radiating port for radiating heat generated from the heating element to the outside only through the substrate. .

The thermal head for high-quality printing according to the present invention is a thermal head for high-quality printing formed by bonding a substrate on which a heating element is mounted and a support plate of the substrate with an adhesive. A heat radiation port for radiating heat generated from the outside to the outside only through the substrate.

That is, the thermal head for high-quality printing of the present invention has a space in a portion corresponding to the back surface of the heating element in the head support plate bonded to the back surface of the glass substrate on which the heating element is mounted with an adhesive. It is arranged.

Thus, the heat generated from the heating element is radiated only to the glass substrate having a uniform thickness, so that the heat in each dot can be radiated evenly, and printing without unevenness can be obtained. Therefore, it is possible to remove printing unevenness caused by a structural cause of the head.

[0011]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a thermal head for high quality printing according to one embodiment of the present invention, and FIG. 2 is a side view of the thermal head for high quality printing according to one embodiment of the present invention.

In FIG. 1 and FIG. 2, a thermal head for high quality printing (hereinafter referred to as a thermal head) 10
Denotes a glass substrate 1, a heating element 2, a glass epoxy substrate 3, an adhesive 4, a head support plate 5, a head driving IC
(Integrated circuit) 6, silicon rubber 7, and bonding wire 8.

The heating element 2 is mounted on the glass substrate 1, and the head drive IC 6 is mounted on the glass epoxy substrate 3. These two substrates are mounted side by side on a head support plate 5 by an adhesive 4, and the heating element 2 and the head drive IC 6 are electrically connected by a pattern on the glass substrate 1 and bonding wires 8. The head drive IC 6 and the head drive IC 6 are covered and protected by silicon rubber 7.

In this case, a heat radiation port 9 is opened in a portion corresponding to the back surface of the heating element 2 of the head support plate 5 to form a cavity (space), and the adhesive 4 is also applied to the heat radiation port 9 portion. Since nothing is done, nothing comes into contact with the glass substrate 1, so that it comes into direct contact with the outside air.

FIG. 3 is a diagram showing a printing structure using the thermal head 10 according to one embodiment of the present invention. These figures 1
The printing operation of the thermal head 10 will be described with reference to FIGS.

When the thermal paper 11 is wound around the platen 12 and enters the thermal head 10, the thermal head 10 is pressed against the thermal paper 11 and the thermal head 10 starts a printing operation.

When the printing operation is started, a signal is sent to the head drive IC 6 on the thermal head 10 by a higher-level head controller (not shown), and a current starts flowing through the heating element 2. Since the heating element 2 is a resistor, it generates heat when an electric current flows, and this heat is transmitted to the thermal paper 11 and the thermal paper 1
1 will develop color.

At the same time, the heat generated from the heating element 2 heats the glass substrate 1, and this heat remains in the glass substrate 1, causing a phenomenon such as heat storage of the thermal head 10. In the prior art, since the head support plate 5 is bonded to the glass substrate 1 via the adhesive 4, a heat storage phenomenon also occurs in the adhesive 4 and the head support plate 5,
At this time, since the heat storage state of each part of the thermal head 10 differs depending on the unevenness of the application of the adhesive 4 and the shape of the head support plate 5, unevenness is easily generated in printing.

On the other hand, in the present embodiment, the provision of the heat radiating holes 9 in the head support plate 5 on the back surface of the heating element 2 causes uneven application of the adhesive 4 and a difference in the heat storage state due to the shape of the head support plate 5. Therefore, the heat accumulation of the thermal head 10 is the same for each dot, and printing unevenness can be prevented.

By providing the heat radiating holes 9 (cavities) in the head support plate 5 on the back surface of the glass substrate 1 on which the heating elements 2 are mounted, heat of the heating elements 2 is applied only to the glass substrate 1 having a uniform thickness. Since the heat is radiated, the thermal head 10
When the heat generated by the current flowing through the heat generating element 2 is radiated, the heat is uniformly radiated at all places of the heat generating element 2, so that the occurrence of printing unevenness due to the heat storage of the thermal head 10 can be prevented.

The prevention of the printing unevenness can be realized without measuring the variation in the printing density of each dot. Therefore, it is possible to prevent the occurrence of print unevenness due to the structural cause of the thermal head 10 without measuring the print density variation of each dot.

[0022]

As described above, according to the present invention, in a thermal head for high-quality printing formed by bonding a substrate on which a heating element is mounted and a support plate of the substrate with an adhesive, the heating element By providing a radiator for radiating the generated heat to the outside only through the board,
There is an effect that it is possible to prevent the occurrence of print unevenness due to a structural cause of the head without measuring the variation in the print density of each dot.

[Brief description of the drawings]

FIG. 1 is a plan view of a thermal head for high quality printing according to an embodiment of the present invention.

FIG. 2 is a side view of a thermal head for high quality printing according to an embodiment of the present invention.

FIG. 3 is a diagram showing a printing structure using a high-quality printing thermal head according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Heating element 3 Glass epoxy board 4 Adhesive 5 Head support plate 6 Head drive IC 7 Silicon rubber 8 Bonding wire 9 Heat radiating port 10 Thermal head for high quality printing 11 Thermal paper 12 Platen

Claims (10)

[Claims] 1. A thermal head for high quality printing which performs high quality printing requiring gradation expression using a thermal head formed by bonding a substrate on which a heating element is mounted and a support plate of the substrate with an adhesive. A thermal printer for high image quality printing, wherein a thermal radiation port for radiating heat generated from the heating element to the outside only through the substrate is provided in the thermal head. 2. The thermal printer according to claim 1, wherein the substrate is made of a material that uniformly radiates heat generated from the heating element. 3. The thermal printer according to claim 2, wherein the substrate is a glass substrate having a uniform thickness. 4. The thermal printer for high-quality printing according to claim 1, wherein the heat radiating port comprises a cavity for directly contacting the back surface of the substrate with the outside air. 5. The thermal printer for high-quality printing according to claim 4, wherein said heat radiation port is formed by forming said cavity in an adhesive layer and a support plate immediately below a back surface of said substrate. 6. A high-quality printing thermal head formed by bonding a substrate on which a heating element is mounted and a support plate of the substrate with an adhesive, wherein heat generated from the heating element is applied only to the substrate. A thermal head for high-quality printing, characterized by having a heat radiating port for radiating heat to the outside through the medium. 7. The thermal head for high-quality printing according to claim 6, wherein the substrate is made of a material that uniformly radiates heat generated from the heating element. 8. The thermal head for high quality printing according to claim 7, wherein said substrate is made of a glass substrate having a uniform thickness. 9. The thermal head for high-quality printing according to claim 6, wherein the heat radiating port comprises a cavity for directly contacting the back surface of the substrate with the outside air. 10. The thermal head for high quality printing according to claim 9, wherein said heat radiating port is formed by forming said cavity in an adhesive layer and a support plate immediately below a back surface of said substrate.