JPH06206311A - Bubble jet printing head - Google Patents

Abstract

PURPOSE:To embody a bubble jet printing head capable of properly carrying out clear printing by rapidly stabilizing print recorded on a recording medium when printing is made on an easily bleeding recording medium, such as plain paper, or a recording medium made of a low-ink staining material, such as an OHP film. CONSTITUTION:An ink-preheating heating resistor 6 for heating ink just before delivery is formed in addition to an ink-delivering heating resistor 3 facing an ink cavity. By applying an electric power to the heating resistor 6, ink to be delivered is sufficiently heated to a required temperature. Thus, the ink is rapidly dried after reaching a recording medium and adhering thereto. In this manner, a bubble jet printing head capable of properly embodying clear recording on various kinds of recording mediums can be produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bubble jet print head used in an ink jet printer.

[0002]

2. Description of the Related Art FIG. 6 is a sectional view showing the structure of a conventional bubble jet print head, and FIG. 7 is a plan view showing the structure of a conventional bubble jet print head. FIG. 8 is an example of a timing chart when driving this conventional bubble jet print head.

In these figures, 1 is a substrate such as a silicon wafer, 2 is a glass glaze layer, 3 is a discharging heat generating resistor, 4 is a power feeding body for supplying power to the discharging heat generating resistor 3,
Reference numeral 5 is a nozzle portion that forms an ink cavity composed of a nozzle wall and a nozzle top plate. Conventionally, generally, a bubble jet print head has a structure as shown in FIG. 6 and FIG. 7, in which ink is filled in the ink cavity, and on top of that, a sufficient amount of electric power is supplied from the power supply body 4 to the heating resistor 3. Is supplied to cause the discharge heating resistor 3 to generate heat. The heat energy is used to generate bubbles used in the ink ejection in the ink.

The time-sequential appearance of the generation of bubbles used for ink ejection is described in the timing chart example of FIG. In the example of the timing chart of FIG. 8, the pulse waveform A is the electric power supplied to the heat generating resistor 3 for ejection, which is about 1 in the past.
It has a pulse width of 0 μsec. It shows the appearance period of a bubble used for ejecting ink, in which B is generated, grows, reaches a maximum, and then shrinks and disappears. The ink is ejected at the timing indicated by C, and the ink ejection is started. At this time, the time from the start of the application of the electric power supplied to the ejection heating resistor 3 to the start of the ink ejection is about 15 to 20 μsec, and the end of the ink ejection is about 100 μsec from the start of the ink ejection. When ink is further continuously ejected, the frequency at which the pulse waveform A is repeated is about 4 KHz (cycle is about 250 μsec). In the bubble jet print head, the bubbles generated in this way create pressure waves that propagate through the ink when they grow and then use the energy of these pressure waves to eject the ink and deposit it on the recording medium. Printing is realized and recording is performed.

[0005]

In the conventional bubble jet print head having such components, in the case of a part of oil-based ink, it is generally unsuitable for the bubble jet print head because of its viscosity and composition. Most oil-based inks and water-based inks are used. In the case of most oil-based inks and water-based inks, recording is performed on plain paper, for example, after the ink droplets adhere to the recording medium and before the adhered ink dries and the print recording is stabilized. In this case, there is a drawback that bleeding occurs mainly due to the roughness of the fibers of plain paper, and only unclear printing is possible. Further, when color printing is performed on plain paper, this bleeding is mainly caused and various inks are mixed unnecessarily, resulting in disturbed color tone and the like, and clear and proper color printing cannot be performed.

Further, when most of the oil-based inks or water-based inks are conventionally used for printing on a recording medium using a material such as an OHP film having a poor hygroscopic property,
It takes a very long time until the ink adhering to the recording medium dries and the print recording is stabilized, and there is a drawback that clear printing is impossible. Moreover, it is not caused by a specific recording medium, and if it comes into contact with the print recording area unnecessarily immediately after printing,
The ink adhered to the recording medium is not completely dried, so that there is a drawback in that print recording is disturbed.

An object of the present invention is to solve such problems in the conventional bubble jet print head, and to use a recording medium such as plain paper in which ink easily bleeds and an ink such as an OHP film having poor hygroscopicity. It is an object of the present invention to provide a bubble jet print head capable of promptly stabilizing a print record realized on a recording medium and realizing an appropriate and clear record when printing on a recording medium.

[0008]

In order to solve the above-mentioned problems, in a bubble jet print head of the present invention, an ink preheat for appropriately warming each ink droplet provided for each print record in an ink cavity. It is configured to have a heating resistor for use.

[0009]

In the bubble jet print head constructed as described above, each print recording is performed in a period from a state immediately before ejection in the ink cavity to a time immediately after the ejection and arrival at the recording medium and immediately before adhering. Bubble jet printing that realizes proper and vivid recording by promptly drying the printed record realized on the recording medium by appropriately warming each ink drop and stabilizing the printed record promptly. The head is realized.

[0010]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of essential parts showing the structure of a bubble jet print head of the present invention. Further, FIG. 2 is a plan view of a main part of the head.

In FIGS. 1 and 2, 1 is a substrate such as a silicon wafer, 2 is a glass glaze layer, 3 is a heating resistor for discharge, 4 is a power feeder for supplying power to each heating resistor, and 5 is a nozzle portion. , 6 are heating resistors for ink preheating. In the present embodiment, it is formed so as to face the ink cavity, and is disposed in a portion between the ejection heating resistor 4 and the periphery of the opening where the ink is ejected on the ejection side.
An ink preheating heating resistor 6 is provided for warming the ink just before ejection.

The ink preheating heating resistor 6 of this embodiment can be easily formed mainly by the same process as the ejection heating resistor 3. The resistance value, which is a basic characteristic of the resistance value, may be set to an appropriate pattern shape in order to set the resistance value appropriately. Then, according to the timing chart example as shown in FIG. 3, by applying appropriate power to the ink preheating heating resistor 6 and the ejection heating resistor 3, it is possible to adequately warm the ink just before ejection. it can. Control of appropriate power application to the ink preheating heating resistor 6 and the ejection heating resistor 3 will be briefly described with reference to the timing chart example of FIG.

In the example of the timing chart of FIG. 3, the pulse waveform D is applied to the heat generating resistor 3 for discharge with the electric power used for discharging the ink. As a result, bubbles for ink ejection are generated in the ejection heat-generating resistor 3, the appearance period of the bubbles is the portion indicated by F, and the ink ejection is the period indicated by G. Then, the pulse waveform E is applied to the ink preheating heating resistor 6 with electric power provided to warm the ejected ink.

In the conventional cycle of 250 μsec, about 10
The time of μsec is consumed to apply the electric power used for ejecting the ink of the pulse waveform D to the ejection heating resistor 3, and from the start of the application of the electric power supplied to the ejection heating resistor 3. The time until the start of ink ejection is approximately 15-
It is about 20 μsec, and the ink ejection is completed at about 100 μsec from the start of the ink ejection. Then, the ink is refilled in the remaining 120 μsec.

In this embodiment, the refilling of the ink is progressing in the time of 120 μsec used for refilling the ink and about 50 μsec in the latter half even while the ink is flying. 180μ
The electric power as shown by the pulse waveform E is applied to the ink preheating heating resistor 6 within sec, and the ejected ink is sufficiently warmed as necessary. Then, the sufficiently warmed ink is ejected at the time point F, reaches the recording medium, and adheres thereto. Due to the kinetic energy of the adhered ink, it spreads to some extent on the recording medium, and the contact surface area with the ambient atmosphere expands.
At the same time, as described above, the ink that has arrived at the recording medium and has adhered thereto has been sufficiently warmed, so that drying on the recording medium is quickly realized.

As described above, in the present embodiment, even when printing is performed on a recording medium such as plain paper on which ink easily bleeds or a material such as an OHP film having poor ink hygroscopicity, printing is performed on the recording medium. A bubble jet print head has been realized that can realize an appropriate and clear record by quickly stabilizing the realized print record.

(Embodiment 2) FIG. 4 is a plan view of the essential portions of a bubble jet print head according to the present invention. In FIG.
Reference numeral 2 is a glass glaze layer, 3 is a discharge heating resistor, 4 is a power feeder for supplying electric power to each heating resistor, 5 is a nozzle portion, 6
Is a heating resistor for ink preheating.

In this embodiment, an ink preheating heating resistor is formed which faces the ink cavity, is arranged on the ink supplying side with respect to the discharging heating resistor 4, and warms the supplied ink immediately before discharging. 6 is equipped. Also in this embodiment, since the ink that has arrived at the recording medium and has adhered thereto has been warmed sufficiently, drying on the recording medium is quickly realized. As a result, also in the present embodiment, even when printing is performed on a recording medium such as plain paper in which the ink easily bleeds and a recording medium using a material having a poor ink hygroscopicity such as an OHP film, the print recording realized on the recording medium. A bubble jet print head has been realized that is capable of quickly stabilizing and achieving appropriate and clear recording.

(Embodiment 3) FIG. 5 is a plan view of a principal portion of a bubble jet print head according to the present invention. In FIG.
Reference numeral 2 is a glass glaze layer, 3 is a discharge heating resistor, 4 is a power feeder for supplying electric power to each heating resistor, 5 is a nozzle portion, 6
Is a heating resistor for ink preheating.

In the present embodiment, the ink is formed facing the ink cavity, and the portion between the ejection heating resistor 4 and the periphery of the opening through which the ink is ejected, and the ink. An ink preheating heating resistor 6 is provided on the side of the ejection heating resistor 4 that supplies ink to the cavity. Even when the heating element 6 for ink preheating is composed of two or more elements in such an arrangement, it is useful for sufficiently warming the ink. Also in this embodiment, since the ink that has arrived at the recording medium and has adhered thereto has been warmed sufficiently, drying on the recording medium is quickly realized.

As a result, even in the present embodiment, even when printing is performed on a recording medium such as plain paper on which ink easily bleeds or a material such as an OHP film, which has poor ink hygroscopicity, it is realized on the recording medium. A bubble jet print head has been realized which can quickly and stably stabilize the printed record and realize an appropriate and clear record.

[0022]

As described above, in the bubble jet print head of the present invention, each print recording is performed in the period from the state immediately before the ejection in the ink cavity to the time immediately after the ejection and arrival at the recording medium and immediately before the adhesion. Even when printing on a recording medium such as plain paper on which ink easily bleeds or a recording medium using a material with poor ink hygroscopicity such as OHP film, by appropriately warming each ink droplet to be recorded There is an effect of realizing a bubble jet print head in which the print record realized above is quickly dried and stabilized quickly, and an appropriate and clear record can be realized.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts showing a structure of a bubble jet print head of the present invention.

FIG. 2 is a plan view of a principal part showing the structure of a bubble jet print head of the present invention.

FIG. 3 is an example of a timing cheat when driving the bubble jet print head of the present invention.

FIG. 4 is a main part plan view showing the structure of a bubble jet print head of the present invention.

FIG. 5 is a plan view of a principal portion showing the structure of the bubble jet print head of the present invention.

FIG. 6 is a cross-sectional view of essential parts showing the structure of a conventional bubble jet print head.

FIG. 7 is a cross-sectional view of essential parts showing the structure of a conventional bubble jet print head.

FIG. 8 is an example of a timing chart when driving a conventional bubble jet print head.

[Explanation of symbols]

 1 Substrate such as Silicon Wafer 2 Glass Glaze Layer 3 Ejection Heating Resistor 4 Power Feeder 5 Nozzle Part 6 Ink Preheating Heating Resistor

Claims (1)

[Claims] 1. A glass grain on a substrate such as a silicon wafer.
Base on which the discharge layer is formed, a plurality of discharge heating resistors,
A power supply for supplying electric power to the heat generating resistor for discharge, and an ink cavity through which ink flows and which supplies / fills the ink and propagates a pressure wave for flying the ink in the filled ink. In a bubble jet print head having a nozzle portion that forms a nozzle wall and a nozzle top plate, for ink preheating for appropriately warming each ink droplet provided for each print recording in the ink cavity. A bubble jet print head having a heating resistor.