JPS63173668A - Energized print head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to an energized print head used in full-color printers and the like.

Conventional technology FIG. 4 is an enlarged perspective view of a conventional energized print head.
is a support layer made of an insulator, 2 is a common electrode, 3 is an insulating layer,
Reference numeral 4 denotes a printing layer, and 4a indicates printing electrodes provided in a number corresponding to the number of pixels, each having a smaller area than the common electrode 1. 4b is an insulating section, and the print electrodes 4a and the insulating sections 4b are arranged alternately. 7 is a support layer made of an insulator.

FIG. 5 is a sectional view showing a state in which printing is performed using a conventional energized print head. A heat-generating sheet 9 is placed on top of the recording paper 8 on which printing is to be performed, and a conventional energized print head is brought into contact with the heat-generating sheet 9. The heat generating sheet 9 has a structure in which a support layer 9b is sandwiched between an electrical resistance layer 9a and an ink layer 9c.

The printing electrode 4a and the common electrode 2 are in contact with the electrical resistance layer 9'a.

12 is a semiconductor switch that applies voltage between the printing electrode 4a and the common electrode 2 by opening and closing according to image data;
Reference numeral 13 denotes a power supply section that applies voltage between the printing electrode 4a and the common electrode 2.

FIG. 6 is a schematic plan view of a conventional energized print head. 1
2a is an integrated circuit in which a plurality of semiconductor switches 12 are configured.

Regarding the conventional energized print head configured as described above. and explain its operation.

When a specific semiconductor switch 12 is closed according to the image data, a voltage is applied between the print electrode 4a and the common electrode 2, and a current flows through the electrical resistance layer 9a between the print electrode 4a and the common electrode 2. Then, since the print electrode 4a has a smaller area than the common electrode 2, the Joule heat generated per unit area is large near the contact portion of the electrical resistance layer 9a with the print electrode 4a.
The temperature near the contact part is higher than other parts, and the heat is transmitted to the ink layer 9c through the support layer 9b, and the ink layer 9
The ink of c is transferred and attached to the recording paper 8, and recording is performed.

Problems to be Solved by the Invention However, in the conventional configuration, when a voltage is applied between the printing electrode 4a in contact with the heat generating sheet 9 and the common electrode 12, the electric resistance layer 9a comes into contact with the printing electrode 4a. Joule heat is generated near the ink layer 9c, but the generated Joule heat is also transmitted to the printing electrode 4a and the recording paper 8, so the ink layer 9c
It takes time to heat the ink layer 9c to a sufficient extent to transfer the ink. Therefore, in order to heat the ink layer 9c more quickly, the voltage between the printing electrode 4a and the common electrode 2 is increased (to increase the Joule heat generated near the contact portion of the electrical resistance layer 9a with the printing electrode 4a). Then, the Joule heat becomes too large and the electrical resistance layer 9 near the contact portion
The support layer 9 may be burnt or the temperature change may be too rapid.
b becomes deformed, resulting in poor print quality.

The present invention solves the above-mentioned conventional problems, and even if the voltage applied between the print electrode and the common electrode is smaller than the voltage applied between the print electrode and the common electrode of a conventional energized print head, it can be applied in a short time. It is an object of the present invention to provide an energized print head that can maintain a temperature high enough to transfer ink in an ink layer and can increase printing speed.

Means for Solving the Problems To achieve this objective, the energized printhead of the present invention comprises:
A preheating electrode was provided for preheating the portion to be heated by applying current through the print electrode, with a constant voltage applied between it and the common electrode.

Effect With the above configuration, since the heat generating sheet is preheated in advance, the temperature of the ink layer can be raised to a temperature sufficient to transfer the ink of the ink layer in a short time.

Embodiment FIG. 1 is an enlarged perspective view of an energized print head in an embodiment of the present invention, in which 1 is a support layer, 2 is a common electrode, 3 is an insulating layer,
4 is a printing layer, and 7 is a support layer, which have the same structure as the conventional energized print head shown in FIG. A preheating electrode 6 is formed on one side of the insulating layer 5 (in the opposite direction to the printing layer 4), and has a smaller area than the common electrode 2 and a larger area than the printing electrode 4a.

FIG. 2 is a sectional view showing a state in which printing is performed using an energized print head in an embodiment of the present invention.

A heat-generating sheet 9 is placed on top of the recording paper 8, and an energized print head according to an embodiment of the present invention is brought into contact with the heat-generating sheet 9. Heat generating sheet9. The recording paper 8° semiconductor switch 12 has the same configuration as the cross-sectional view shown in FIG. 5 in a state where printing is performed using a conventional energized print head. Reference numeral 11 represents a power supply unit that applies a voltage between the preheating electrode 6 and the common electrode 2, and reference numeral 10 represents a power supply unit that applies a voltage between the print electrode 4a and the common electrode 2.

FIG. 3 is a schematic plan view of an energized print head according to an embodiment of the present invention, and 12a is an integrated circuit including a plurality of semiconductor switches, which is the same as the conventional one.

The operation of the energized print head in one embodiment of the present invention constructed as described above will be described below.

A constant voltage is applied between the common electrode 2 and the preheating electrode 6 by the power supply unit 11, and a current flows through the electrical resistance layer 9a between the common electrode 2 and the preheating electrode 6. Then, since the area of the preheating electrode 6 is smaller than that of the common electrode 2, the area of the preheating electrode 6 is smaller than that of the printing electrode 4 of the electrical resistance layer 9a.
Since the Joule heat generated per unit area is large near the contact area with the contact area, the temperature near the contact area becomes higher than other areas, and the heat is transmitted to the ink layer 9C through the support layer 9b. Since the voltage applied between the common electrodes 2 is such that the ink in the ink layer is not transferred, it is not possible to print on the recording paper 8. Since the heat generating sheet 9 and the recording paper 8 are fed in the direction of arrow A, the portion of the heat generating sheet 8 heated by the preheating electrode 6 is fed below the print electrode 4a.

Next, when a specific semiconductor switch 12 is closed according to the image data, a voltage is applied between the printing electrode 4a and the common electrode 2, and a current flows through the electrical resistance layer 9a between the printing electrode 4a and the common electrode 2. Then, the Joule heat generated per unit area near the contact area of the electrical resistance layer 9a with the printing electrode 4a is larger than that near the contact area of the electrical resistance layer 9a with the common electrode 2, so the temperature near the contact area becomes higher. The ink of the ink layer 9c is transferred and attached to the recording paper 8, and is recorded. At this time, since the heat generating sheet 9 is heated in advance by the preheating electrode 6 to such an extent that the ink of the ink layer 9C is not transferred, when a voltage is applied between the printing electrode 4a and the common electrode 2, the heat generating sheet 9 prints. The ink layer 9 immediately forms near the contact area with the electrode 4a.
The temperature can be raised to a level at which the ink of c can be transferred. Therefore, the ink in the ink layer 9c is transferred to the recording paper 8 immediately after a voltage is applied between the common electrode 2 and the print electrode 4a. In this way, since the time required for ink transfer is short, printing speed can be increased.

Effects of the Invention The present invention provides a preheating electrode for preheating the area to be heated by applying current to the print electrode, and a constant voltage is applied between the print electrode and the common electrode. (However, the area near the contact area of the heating sheet with the printing electrode is preheated by the preheating electrode to the extent that the ink in the ink layer will not be transferred, so the ink in the ink layer near the contact area will be transferred in a short time.) The printing speed can be increased because it can be heated to a temperature that is high enough to It can be done cheaply.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an energized print head according to an embodiment of the present invention, FIG. 2 is a sectional view showing a state in which printing is performed using the energized print head according to an embodiment of the present invention, and FIG. 3 is a schematic diagram of the same. 4 is a perspective view of a conventional energized print head, FIG. 5 is a sectional view showing a state in which printing is performed using the conventional energized print head, and FIG. 6 is a schematic plan view thereof. 1...Supporting layer 2...Common electrode 3...
・Insulating layer 4...Printing layer 4a...Printing electrode 4b...Insulating part 5...Insulating layer
6... Preheating electrode 7... Name of support layer agent Patent attorney Toshio Nakao and 1 other person /--- Support layer 2 - Machine f electromagnetic 3 - Gun ridge eyebrow 4 - Print layer - Print electrode 4b-Insulating layer 6-Children 8Electric food 8-Paper 9-Interlacing sheet 9a-1 Electrical resistance layer L-Support layer 9cm-Ink layer 10-Recording paper Fig. 3 1-m-Support Layer 2-m-Concurrent pole 3-Last layer 4-Printing layer 4a-Printing electromagnetic 46-Zone #7-Support layer Fig. 4Vne 4b

Claims (1)

[Claims] a common electrode, a printing electrode to which a voltage according to image data is applied between the common electrode, and a preheating electrode to which a voltage is applied between the common electrode and to preheat a portion to be electrically heated by the printing electrode; An energized print head characterized by being equipped with.