JP2002331666A - Ink jet recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording head which enables a time for cooling while pressuring a flexible film wiring board to be shortened, and the like by improving the mounting margin of the flexible film wiring board and a recording element substrate, almost prevents an electrical failure by an interfacial separation between the flexible film wiring board and a thermosetting adhesive, and can reduce costs by a tact increase. SOLUTION: In the vicinity of an electric connecting part T of the flexible film wiring board 103 to be electrically connected to the recording element substrate 101, a hole or a notched open part 1034 is set to a cover film for protecting a conductor 1031 of the flexible film wiring board 103. The thermosetting adhesive 109 or a sealant 110 is filled into the open part 1034.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to ink jet recording and an ink jet recording head used in an ink jet recording apparatus.

[0002]

2. Description of the Related Art An ink jet printing apparatus is a so-called non-impact printing type printing apparatus. High-speed recording and recording on various recording media are possible, and there is a feature that almost no noise is generated at the time of recording. For this reason, it has been widely adopted as a device that carries a recording mechanism such as a printer, a word processor, a facsimile, and a copying machine.

[0003] The ink-jet recording is a typical method using an electrothermal transducer, in which minute droplets are ejected from minute ejection ports, and recording is performed on recording paper.

In general, an ink jet recording apparatus includes an ink jet recording head for forming droplets and a supply system for supplying ink to the ink jet recording head.

In an ink jet recording head using an electrothermal transducer, an electrothermal transducer is provided in a pressurized chamber, and thermal energy is given to a recording liquid by applying an electric pulse serving as a recording signal to the recording medium. The bubble pressure at the time of bubbling (at the time of boiling) of the recording liquid caused by the phase change of the liquid is used for discharging the recording liquid droplets.

Further, in the case of an ink jet recording head using an electrothermal transducer, a method (edge shooter) of discharging recording liquid in parallel to a substrate on which the electrothermal transducer is arranged and an electrothermal transducer are arranged. There is a method (side shooter) for ejecting a recording liquid perpendicularly to a substrate.

A substrate on which the above-described electrothermal transducers are arranged and has a function of discharging a recording liquid is hereinafter referred to as a recording element substrate.

In recent years, ink jet recording heads have been reduced in size and multi-colored. For example, a single ink jet recording head that discharges recording liquids of four colors of yellow, magenta, cyan, and black has been commercialized. ing.

FIGS. 4 and 5 show an example of a mounting form of an ink jet recording head for discharging recording liquids of different colors from a plurality of recording element substrates.

FIG. 4 is a plan view showing a configuration example of a conventional ink jet recording head.

FIG. 5A is an enlarged view of FIG.
FIG. 5B is a sectional view taken along line AA of FIG.

FIG. 5A shows the thermosetting adhesive 109 shown in FIG. 5B for simplicity.
And the sealant 110 are omitted.

Reference numeral 101 denotes a printing element substrate (Si substrate), 10
2 is a supporting member for supporting the recording element substrate 101; 103 is a flexible film wiring substrate (hereinafter abbreviated as flexible); 104 is an ejection port for ejecting ink droplets;
Reference numeral 5 denotes a common liquid chamber formed on the recording element substrate 101 by anisotropic etching or blast processing.

Reference numeral 106 denotes a nozzle connected to the discharge port 105;
07 is an electrode provided on the recording element substrate 101, 109 is a thermosetting adhesive, 110 is a sealant, 1000 is a heat tool, 1021 is provided on the support member 102, and supplies ink to the common liquid chamber 105. An ink flow path, 1031 is a conductor provided on the flexible member 103, 1032 is an upper cover film, 1033 is a lower cover film, 1035 is an external input pad, and T is an electric connection portion.

The printing element substrate 101 is bonded and fixed to a support member 102.

The electrodes 107 of the recording element substrate 101 are mounted and electrically connected to a conductor 1031 serving as a connection terminal of the flexible member 103 by thermocompression bonding using a thermosetting adhesive 109 with a heat tool 1000. An electric signal for ejecting ink from 104 is supplied from the conductor 1031 of the flexible 103 through the electric connection portion T.

The conductor 1031 of the flexible cable 103 is covered with an upper cover film 1032 and a lower cover film 1033.
032 covers only the upper part.

Usually, since there is a step of passing through a reflow furnace in the mounting step, a polyimide film having high heat resistance is used as the cover film.

The flexible 103 has an external input pad 1035 for supplying an electric signal such as recording information from the recording apparatus main body to the ink jet recording head.

[0020]

However, the above-described ink jet recording head has the following problems.

In an ink jet recording head using an electrothermal transducer, the head temperature is raised to about 60 ° C. during high-duty or long-time continuous printing, and then cooled.

It is a feature of the ink jet recording head using the electrothermal transducer that the repetition of the temperature increase and the cooling occurs frequently.

At this time, the recording element substrate 101 and the flexible 10
In No. 3, the end portion X of the electrical connection portion T between the recording element substrate 101 and the flexible member 103 has a large stress because the thermal expansion coefficient is different, and depending on the bonding state between the flexible member 103 and the thermosetting adhesive 109, the flexible member 103 and the flexible member 103 may have different stresses. Separation from the thermosetting adhesive 109 occurs and floats on the conductor 1031 and the electrode 107, so that an electrical open failure may occur.

In addition, in order to minimize the occurrence of the above-mentioned inconveniences, it is necessary to delicately set the heating and pressurizing conditions of the heat tool 1000 when the recording element substrate 101 and the flexible member 103 are joined. Since it is necessary to take a long time for cooling while the pressure is kept high, the cost is increased due to the tact reduction.

The present invention has been made in view of the above points, and a purpose thereof is to protect a flexible conductor in the vicinity of a flexible electrical connection portion electrically connected to a printing element substrate. By providing a hole or a cut-out opening in the cover film to be filled and filling the opening with a thermosetting adhesive or a sealing agent, almost no electrical failure occurs due to peeling of the interface between the flexible and the thermosetting adhesive. In addition, by improving the margin of mounting of the flexible element and the recording element substrate, it is possible to shorten the time for cooling while maintaining the pressure of the flexible element, and to provide an ink jet recording head capable of reducing the cost by increasing the tact time. It is in.

[0026]

Therefore, in the present invention, an object of the present invention is to provide an ink jet recording head described in any one of the following items (1) to (7) to achieve the above object. It is.

(1) A recording element substrate having an ejection port array from which a recording liquid is ejected by a pressure based on the generation of bubbles generated by thermal energy, and a flexible film electrically connected to the recording element substrate by a thermosetting adhesive A flexible film wiring electrically connected to a recording element substrate in an ink jet recording head having a wiring substrate (flexible) and a sealant for sealing an electric connection portion between the recording element substrate and the flexible film wiring substrate (flexible). In the vicinity of the electrical connection portion of the substrate (flexible), a cover film for protecting the conductor of the flexible film wiring substrate (flexible) is provided with a hole or a notched open portion, and the thermosetting adhesive or the sealing is provided in the open portion. An ink jet recording head characterized by being filled with a stopper.

(2) The ink jet recording apparatus according to (1), wherein the open portion provided in the flexible film wiring board (flexible) is a hole in a cover film of the flexible film wiring board (flexible). head.

(3) The open portion provided in the flexible film wiring board (flexible) is a notch of the cover film, and the conductor of the flexible film wiring board (flexible) is exposed by the open portion. The inkjet recording head according to the above (1), wherein

(4) An island-shaped projection formed of a nozzle forming material on the recording element substrate is located at an open portion provided on the flexible film wiring substrate (flexible). The inkjet recording head according to the above item.

(5) The thermosetting adhesive and the sealant are mainly made of the same material.
Item 7. The ink jet recording head according to Item 1.

(6) The ink jet recording head according to the above (1), wherein the thermosetting adhesive and the sealant are mainly made of an epoxy resin.

(7) The ink jet recording head according to the above (1), wherein the thermosetting adhesive is an anisotropic conductive adhesive containing conductive particles.

[0034]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIGS. 1A and 1B show Embodiment 1 of an ink jet recording head according to the present invention.

The basic components of the first embodiment of the ink jet recording head according to the present invention are substantially the same as those in the prior art except for the structure of the opening 1034. Are denoted by the same reference numerals, and detailed description thereof will be omitted.

Reference numeral 1034 denotes an opening provided on the upper cover film 1032.

FIG. 1A is a plan view seen from the ink droplet ejection direction, and shows the vicinity of the end of the electrical connection portion T between the flexible 103 and the recording element substrate 101.

FIG. 1A omits the thermosetting adhesive 109 and the sealant 110 shown in FIG. 1B for easy understanding of the present invention.

FIG. 1B is a sectional view taken along the line BB of FIG. 1A.

The ink jet recording head of the present invention comprises, for example, a recording element substrate 101 for black and yellow,
For example, a recording element substrate 101 for magenta and cyan,
It is composed of support members 102 and 103.

Reference numeral 104 denotes a discharge port for discharging ink droplets, and reference numeral 105 denotes a common liquid chamber for supplying ink to a nozzle 106 connected to the discharge port.

The common liquid chamber 105 includes the recording element substrate 101
(Si substrate) is formed by anisotropic etching or blasting.

The support member 102 supports the recording element substrate 101 and has an ink flow path 1021 formed therein, and supplies ink to the common liquid chamber 105.

Further, the electrode 107 of the recording element substrate 101
Are provided in a direction perpendicular to the rows of the ejection ports 104.

Although only a few electrodes 107 are shown, tens to hundreds of electrodes 107 are provided in an actual product.

The electrodes 107 are gold bumps formed by stud bumps or plated bumps.

The recording element substrate 101 has its back side bonded to the support member 102 with high accuracy of several to several tens of μm.

After the recording element substrate 101 is bonded to the support member 102, the electrode 10
7, electrically connected at an electrical connection portion T,
Further, the flexible 103 is provided with an external input pad 106 for supplying an electric signal such as recording information to the ink jet recording head from a recording apparatus main body side (not shown).

In the vicinity of the electrical connection portion T of the flexible 103 with the recording element substrate 101, an open portion 1034 opened in the cover film is provided.

The thermosetting adhesive 109 for securing the electrical connection between the flexible 103 and the recording element substrate 101 melts when heated with a heat tool, and emerges from the opening 1034 to the surface to be cured.

With this configuration, even under severe conditions of the temperature rise and fall of the ink jet recording head, stress of thermal expansion and contraction of the flexible 103 is received by the columns of the thermosetting adhesive 109 entering the respective open portions 1034. Therefore, peeling of the flexible 103 and the thermosetting adhesive 109 hardly occurs.

The thermosetting adhesive 109 can be similarly used when an anisotropic conductive adhesive containing conductive particles is used.

For example, when the single particle diameter of nickel is 2 to 6 μm
A recording element substrate 101 is formed using an anisotropic conductive adhesive film composed of an adhesive mainly composed of conductive particles and an epoxy resin.
The electrodes 107 (gold bumps) and the gold-plated conductors 1031 of the flexible 103 can be heated and pressed at a temperature of 170 to 250 ° C. to be electrically connected and fixed.

Further, by using the same material as the thermosetting adhesive 109 for the sealing agent 110, the adhesion with the thermosetting adhesive 109 becomes stronger.

As a material, since it comes into contact with ink,
Use an epoxy type that is resistant to ink of about PH10.

By using the same material, even if the thermosetting adhesive 109 is cured in the middle of the opening 1034, the sealing agent 110 enters the opening 1034,
The same effect as described above can be obtained by firmly bonding to the thermosetting adhesive 109.

(Embodiment 2) FIGS. 2A and 2B show Embodiment 2 of the ink jet recording head of the present invention.

The basic components of the second embodiment of the ink jet recording head according to the present invention are substantially the same as those of the first embodiment except for the structure of the opening 1034. Are denoted by the same reference numerals, and detailed description thereof will be omitted.

The opening 1034 is notched.

FIG. 2A is a plan view as seen from the ink droplet ejection direction, and shows the end of the electrical connection portion T between the flexible 103 and the recording element substrate 101.

FIG. 10A is a diagram showing a thermosetting adhesive 10 shown in FIG. 10B for easy understanding of the present invention.
9 and the sealant 110 are omitted.

FIG. 2B is a sectional view taken along line CC of FIG. 2A.

The open portion 1034 is located near the electrical connection portion T,
The cutout is provided in the upper cover film 1032, and the conductor 1031 is exposed by this cutout.

The thermosetting adhesive 109 for securing the electrical connection between the flexible 103 and the recording element substrate 101 melts when heated by a heat tool, and covers and hardens the surface of the conductor 1031.

With this configuration, even when the temperature of the recording head rises and falls strictly, each conductor 1
Since the stress of the thermal expansion and contraction of the flexible 103 is received by the wall of the thermosetting adhesive 109 interposed between 031 and the flexible 103, the peeling of the thermosetting adhesive 109 hardly occurs.

(Embodiment 3) FIGS. 3A and 3B are diagrams showing Embodiment 3 of the ink jet recording head of the present invention.

The basic components of the third embodiment of the ink jet recording head according to the present invention are substantially the same as those in the first embodiment except for the structures of the island-like projections 200 and the open portions 1034. The same components are denoted by the same reference numerals, and the detailed description thereof will be omitted.

Reference numeral 200 denotes an island-shaped projection provided on the recording element substrate 101.

FIG. 3A is a plan view seen from the ink droplet ejection direction, and shows the end of the electrical connection portion T between the flexible 103 and the recording element substrate 101. FIG.

FIG. 10A is a view showing the thermosetting adhesive 10 shown in FIG. 10B for easy understanding of the present invention.
9 and the sealant 110 are omitted.

FIG. 3B is a sectional view taken along line DD of FIG.

In the vicinity of the electrical connection portion T of the flexible 103 with the recording element substrate 101, an open portion 1034 opened in the cover film is provided.

In this open portion 1034, an island-shaped projection 200 formed on the recording element substrate 101 at the same time when the nozzle is formed is located.

The island-shaped projection 200 is the same as the nozzle forming material, and is made of epoxy resin.

In this embodiment, the thermosetting adhesive 109 more reliably enters the opening 1034 and the conductor 1031
Cures over the surface of

With this configuration, even if the temperature of the recording head rises and falls strictly, each conductor 1
Since the stress of the thermal expansion and contraction of the flexible 103 is received by the wall of the thermosetting adhesive 109 interposed between 031 and the flexible 103, the peeling of the thermosetting adhesive 109 hardly occurs.

[0078]

As described above, according to the present invention,
Repetitive stress of heating and cooling when driving an inkjet recording head using an electrothermal transducer (the head temperature rises to about 60 ° C during high-duty or long-time continuous printing, and then cools) Since the thermosetting adhesive or the sealant filled in the open portion of the flexible member is received, electric failure due to interface peeling between the flexible member and the thermosetting adhesive caused by the conventional configuration hardly occurs.

In addition, since the margin for mounting the flex and the recording element substrate is improved, it is possible to shorten the time for cooling the flex while pressurizing the flex, and to provide an ink jet recording head capable of reducing the cost by increasing the tact time. .

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of an ink jet recording head according to the present invention.

FIG. 2 is a diagram showing an ink jet recording head according to a second embodiment of the present invention.

FIG. 3 is a diagram showing a third embodiment of the ink jet recording head of the present invention.

FIG. 4 is a plan view illustrating a configuration example of a conventional inkjet recording head.

FIG. 5 is a diagram illustrating a configuration example of a conventional inkjet recording head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Recording element board 102 Support member 103 Flexible film wiring board (flexible) 104 Discharge port 105 Common liquid chamber 106 Nozzle 107 Electrode 109 Thermosetting adhesive 110 Sealant 200 Island-shaped protrusion 1000 Heat tool 1031 Conductor 1032 Upper cover film 1033 Lower cover film 1034 Open part 1035 External input pad T Electrical connection part

Claims (7)

[Claims] 1. A printing element substrate having an ejection port array from which a recording liquid is ejected by pressure based on the generation of bubbles generated by thermal energy, and a flexible film wiring electrically connected to the printing element substrate by a thermosetting adhesive. A flexible film wiring substrate electrically connected to a recording element substrate in an ink jet recording head including a substrate (flexible) and a sealant for sealing an electrical connection portion between the recording element substrate and the flexible film wiring substrate (flexible). In the vicinity of the (flexible) electrical connection portion, a cover film for protecting the conductor of the flexible film wiring board (flexible) is provided with an opening or cutout in the cover film, and the thermosetting adhesive or the sealing is provided in the opening. An ink jet recording head characterized by being filled with an agent. 2. The ink jet recording head according to claim 1, wherein the opening provided in the flexible film wiring board (flexible) is a hole in a cover film of the flexible film wiring board (flexible). 3. An open portion provided in the flexible film wiring board (flexible) is a cutout of the cover film, and the conductor of the flexible film wiring board (flexible) is exposed by the open portion. The ink jet recording head according to claim 1, wherein: 4. An island-shaped projection formed of a nozzle forming material on said recording element substrate is located at an open portion provided on said flexible film wiring substrate (flexible). Inkjet recording head. 5. The ink jet recording head according to claim 1, wherein the thermosetting adhesive and the sealant are made of the same main material. 6. The ink jet recording head according to claim 1, wherein a main material of the thermosetting adhesive and the sealing agent is an epoxy resin. 7. The ink jet recording head according to claim 1, wherein the thermosetting adhesive is an anisotropic conductive adhesive containing conductive particles.