JP2003211678A - Recording element unit of inkjet head - Google Patents

Abstract

[PROBLEMS] To prevent an adhesive from flowing out to a lead of an electric wiring tape when an electric wiring tape is adhered to an element substrate in a recording element unit of an ink jet head. SOLUTION: The outer periphery of the recording element mounting surface is chamfered with the electric wiring tape bonding surface of the element substrate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording element unit that constitutes an inkjet head.

[0002]

2. Description of the Related Art FIGS.
It is a bubble-jet (registered trademark) type recording head of a side shooter type that discharges liquid droplets in a direction substantially perpendicular to a heater substrate.

The recording head H1001 comprises a recording element unit H1002, an ink supply unit H1003 and a tank holder H2000. As shown in the exploded perspective view of FIG. 1, the recording element unit H1002 has a first recording element H1100 and a second recording element H1100. The recording element H1101, the first plate H1200, the electric wiring tape H1300, the electric contact substrate H2200, and the second plate H1400 are included, and the ink supply unit H1003 includes:
An ink supply member H1500, a flow path forming member H1600,
It is composed of a joint rubber H2300, a filter H1700, and a seal rubber H1800.

Next, the recording element unit will be described.

In the recording element unit, a plate assembly is formed by joining a first plate and a second plate, a recording element substrate is mounted on the plate assembly, an electric wiring tape is laminated and the recording element substrate is electrically joined. Mounting is performed in the order of sealing electrical connection parts and the like.

The first plate H1200, which is required to have a plane accuracy because it affects the ejection direction of the droplets, has a thickness of 0.5 to 1.
It is formed of a 0 mm alumina (Al ₂ O ₃ ) material. The first plate H1200 has an ink supply port H1201 for supplying black ink to the first recording element substrate H1100 and ink for supplying cyan, magenta, and yellow ink to the second recording element substrate H1101. A supply port 1201 is formed.

The second plate H1400 has a thickness of 0.5.
A first recording element H1100 and a second recording element, which are a single plate member of 1 mm to 1 mm, are formed of, for example, a metal such as alumina or aluminum, or a resin such as polysulfone, and are adhesively fixed to the first plate H1200. It has a slot-shaped opening H1401 larger than the outer dimension of the element H1101. The second plate H1400 is the first plate H12.
00 is laminated and fixed on the substrate 00 with an adhesive to form a plate assembly H1202 which is an element substrate.

The first recording element H1100 and the second recording element H1101 are adhesively fixed to the surface of the first plate H1200 of the plate assembly with high positional accuracy.

Recording element H1 having a nozzle array H1104
100 and H1101 have a known structure as a side shooter type bubble jet substrate, and an ink supply port formed of a long groove-shaped through-hole as an ink flow path and an ink supply port are sandwiched between a Si substrate having a thickness of 0.5 to 1 mm. 1 on each side
A heater row, which is a discharge means arranged in a staggered manner row by row,
It has an electrode part connected to the heater by electric wiring and having connection pads arranged on both outer sides of the substrate. Au stud bumps H1102 are formed on the connection pads (FIG. 3A).

Electric wiring tape (hereinafter wiring tape) H1
300 is a laminated body of tape base material, wiring, and cover layer,
First recording element H1100 and second recording element H1101
An electric signal for ejecting ink is applied to.
A TAB tape can be considered as an example. Inner leads (hereinafter referred to as leads) H1302 in which wirings are exposed in the device holes H1314 are provided in the element connection portions corresponding to the sides of the two device holes H1314 corresponding to the recording elements. The wiring tape H1300 is adhered and fixed on the cover layer side to the surface of the second plate via an epoxy resin adhesive layer.

Wiring tape H1300 and recording element 110
0 and H1101 are electrically connected to each other through a thermosonic bonding method or an anisotropic conductive tape. In the case of a TAB tape, inner lead bonding (ILB) by a thermosonic bonding method is suitable. In the recording element unit of FIGS. 1 to 3, the lead H130 of the wiring tape H1300 is used.
2 and the stud bump on the recording element are ILB bonded (FIG. 3B).

After electrical connection between the wiring tape and the recording element,
The first sealant H1307 and the second sealant H1 are provided to protect the electrical connection part from corrosion by ink and external impact.
It is sealed by 308. The first sealant mainly seals the outer peripheral portion of the mounted recording element, and the second sealant is
The front side of the electrical connection between the recording element and the electrode wiring tape is sealed.

[0013]

FIG. 4 is a view for explaining a conventional recording element unit, and corresponds to the AA sectional view of FIG.

The electric wiring tape H1300 and the plate assembly H1202 are adhered by transferring the thermosetting epoxy adhesive H1305 onto the second plate H1400 and then thermally bonding the wiring tape H1300 (FIG. 4).
(A)).

At this time, the adhesive H1305 just before curing is extruded from between the cover layer H1304 of the wiring tape H1300 and the second plate H1400 (FIG. 4 (b)) and flows near the root of the lead H1302.

The appropriate amount of the extruded adhesive fixes the roots of the leads to reduce variations in the height of the leads with respect to the device, and contributes to highly reliable ILB.

However, during production, the transfer amount of the adhesive fluctuates to some extent, and when the transfer amount becomes excessive, the adhesive flows from the root of the lead to the tip direction and wets the lead surface. Figure 5
It is the figure which looked at the state where adhesive H1305 flowed on the surface of lead H1302 from the joint side. The adhesive that covers and solidifies the lead surface limits the bending elasticity of the lead and reduces the bonding strength between the lead H1302 and the stud bump H1102 during ILB. Alternatively, due to the rigidity of the leads, the stud bump H1102 may not be connected to the element H after the ILB.
1100 causes a defect of being peeled off.

Further, the adhesive H1305 is the lead H130.
If the surface of 2 is covered thickly, the bonding of the lead and the stud bump itself becomes impossible due to the interference of the adhesive resin layer.

A very simple method of avoiding this is to reduce the amount of application or transfer of the adhesive H1305. However, in this case, the adhesion of the roots of the inner leads becomes uncertain, the heights of the leads and the stud bumps vary, and the ILB becomes defective. Further, if the height of the lead itself becomes large, the height of the encapsulant covering the inner lead after the ILB from the surface of the recording element also becomes large. In the inkjet head, the recording element faces the recording paper, and the distance between them is controlled to maintain the printing quality. However, when the height of the sealant becomes large, the recording paper and the sealant come into contact with each other, and the inkjet head Damage to. If the distance from the recording paper is increased in order to avoid contact, the print quality will deteriorate.

Further, the TAB may not be flatly adhered to the plate assembly, and may cause partial floating. TAB
The surface of the tape H1300 has recording elements H1100, H1.
A cap member for preventing the nozzle of 101 from being dried is brought into contact, but partial floating of the TAB tape causes a leak between the cap and the TAB tape, which deteriorates the capping performance.

Therefore, it is necessary to apply or transfer an amount of adhesive required for securely and flatly adhering the TAB tape to the plate assembly and to prevent a part of the adhesive from flowing out to the inner leads.

[0022]

The invention according to the present application is
This is done in view of the above problems.

According to the present invention, there is provided a recording element unit in which an electric wiring tape is laminated and adhered on an element substrate on which a recording element having a discharge means is mounted, and the electric wiring tape and the recording element are electrically connected. A recording element unit having a chamfer on a ridgeline of a device hole on a wiring tape adhering surface.

(Operation) According to the invention of the present application, the adhesive extruded from between the plate assembly and the cover layer of the wiring tape to the vicinity of the element connection portion of the wiring tape when the electric wiring tape is pressure bonded is Since it flows down along the chamfer of the substrate, it does not flow out to the surface of the inner lead protruding from the element connecting portion and exposed. For this reason, an undesired increase in bending rigidity of the lead is prevented.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to FIG. 6 is viewed from the same direction as FIG. 4, and FIGS.
It is a figure explaining the characteristic composition of this embodiment applicable to the recording element unit of.

Alumina first plate H1200 and 0.
The recording element H1100 made of a 0.65 mm silicon substrate is mounted on the plate assembly H1202 to which the second plate H1400 of 6 mm thick alumina is bonded. After mounting the recording element, the thermosetting epoxy adhesive is transferred to the second plate H1400 by a stamping method so that the thermosetting epoxy adhesive has a thickness (average thickness) of about 10 μm.

TAB tape H13 which is an electric wiring tape
00 is a 20 um-thick printed on the copper foil wiring by adhering a 35 um copper foil forming a wiring on a base film (tape base material) made of 50 um polyimide via a copper foil adhesive (wiring adhesive) H1313. Has a structure covered with a cover layer made of a solder resist layer. Inner leads H13 protruding 0.6 mm from the element connecting portion H1311 of the device hole H1314 of the TAB tape and exposed.
In No. 02, the surface of the copper foil is plated with gold, and are arranged with a width of 85 μm, a thickness of 30 to 35 μm, and an adjacent pitch of 165 μm.

The TAB tape H1300 has a lead H13.
02 is aligned so as to overlap the bumps H1102 on the recording element, and the second plate surface and the cover layer H1 are aligned.
It is adhesively fixed with a thermosetting epoxy adhesive with 304.

FIG. 6B shows a plate assembly H1202.
It is the figure which stuck the TAB tape H1300 to. Since the C surface is provided on the recording element H1100 side of the second plate H1400, the extruded adhesive H1305 is C
It flows downward along the surface H1405.

In this embodiment, the plate assembly is described as having two parts, but it may be provided as one part. Further, the chamfer is described as the C chamfer, but it may be a step.

[0031]

As is apparent from the above description, according to the invention of the present application, it is necessary to securely and flatly adhere the wiring tape to the plate assembly in order to maintain the printing quality and reliability of the inkjet head. When a certain amount of adhesive is used, the adhesive extruded from between the plate assembly and the cover layer of the wiring tape to the vicinity of the element connection portion of the wiring tape by the pressure bonding of the wiring tape is prevented from flowing out to the lead surface. Therefore, the bending rigidity of the lead does not change before and after the adhesive is solidified, and the bonding surface of the lead is not covered with the resin, so that reliable and good bonding can be performed thereafter.

The invention of the application is not limited to the specific materials, shapes, and other structures in the embodiments.
For example, the electric wiring tape is not limited to the TAB tape and may be a flexible substrate or the like.

[Brief description of drawings]

FIG. 1 is a diagram illustrating an inkjet head to which the present invention can be applied.

FIG. 2 is a diagram illustrating an inkjet head to which the present invention can be applied.

FIG. 3 is a diagram illustrating an inkjet head to which the present invention can be applied.

FIG. 4 is a diagram illustrating a conventional manufacturing process of a recording element.

FIG. 5 is a diagram illustrating a conventional manufacturing process of a recording element.

FIG. 6 is a first embodiment of the present invention.

[Explanation of symbols]

H1002 Recording element unit H1003 Ink supply unit H2000 tank holder H1100 First recording element H1102 Stud bump H1200 first plate H1202 plate assembly H1300 electric wiring tape H1302 Inner lead H1304 cover layer H1305 adhesive H1306 thinning pattern H1311 Element connection part (of electric wiring tape) H1312 cover film H1313 Copper foil adhesive H1314 device hole H1400 Second plate H1405 C surface of the second plate

Continued front page    (72) Inventor Toshio Kashino             Kyano, 3-30-2 Shimomaruko, Ota-ku, Tokyo             Within the corporation F-term (reference) 2C057 AF93 AG84 AK07 AP25 BA13

Claims (4)

[Claims] 1. A recording element unit in which an electric wiring tape is laminated and adhered onto an element substrate on which a recording element having a discharge means is mounted, and the electric wiring tape and the recording element are electrically connected to each other. Is a recording element unit having a step between a surface on which the recording element is mounted and a surface on which the electric wiring tape is adhered, the recording element unit having an adhesive flow-in prevention mechanism for adhering the wiring tape. 2. The recording element unit according to claim 1, wherein the flow-in prevention mechanism is a chamfer formed on a ridge line of a device hole on a wiring tape adhering surface. 3. The recording element unit according to claim 2, wherein the chamfer is a C chamfer. 4. The recording element unit according to claim 2, wherein the chamfer is a step.