JP2007111904A - Liquid delivering head and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it compatible both to prevent an adhesive from flowing into a head body (on the head body) during bonding and to ensure reliability of adhesion (ink resistance) in a liquid delivering head made by bonding an orifice plate and the head body with the adhesive. <P>SOLUTION: Before a UV-light curable or a UV-curable and heat-curable adhesive is transferred on the head body, it is irradiated partially with a very small amount of UV-light. Thereafter, the adhesive is transferred on the head body to bond the orifice plate and the adhesive is completely cured by heat curing. When the whole adhesive is irradiated with the very small amount of the UV-light before transferring, reliability of the adhesion is decreased. In addition, when transferring is performed without irradiating with the UV-light, a large amount of the adhesive flows into the head body. By irradiating partially with a very small amount of the UV-light before transferring, both ensuring the reliability of the adhesion and preventing a large amount of the adhesive from flowing into the head body, can become compatible. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ink jet recording head used in printers, video printers, and the like as output terminals of copying machines, facsimiles, word processors, host computers and the like. In particular, it has a substrate on which a heating element (electrothermal conversion element) that generates thermal energy as ink ejection energy is formed, and ink for recording is ejected from the ejection port (orifice) as flying droplets and adheres to the recording medium It is related with the liquid discharge head which records by making it.

  Note that “recording” in the present invention includes not only forming an image having a meaning such as a character or a figure on a recording medium but also forming an image such as a pattern having no meaning.

  Conventionally, the method of recording using a liquid discharge head is non-impact recording, with low noise, high density, high-speed printing possible, maintenance is relatively easy and can be maintenance-free, etc. In recent years, it has been widely used.

  An example of this type of conventional liquid discharge head will be described with reference to FIG.

  The liquid discharge head shown in FIG. 6 includes a heating element 1005 that is an energy generating element that generates energy for discharging ink, a substrate 1001 in which a plurality of grooves constituting the ink flow path 1006 are provided in parallel, and an ink supply. A top plate 1002 having a mouth, and an orifice plate 1004 formed at a position where the orifice 1012 for ejecting ink is connected to the liquid channel 1006 are bonded to the end surfaces of the substrate 1001 and the top plate 1002. Have.

  The orifice 1012 formed in the orifice plate 1004 is very fine, and the orifice 1012 is one of the important factors that influence the ejection characteristics of the liquid ejection head. That is, the orifice plate 1004 of the liquid ejection head is excellent in workability because the fine orifice 1012 is formed, and needs to have good ink resistance because it is in direct contact with ink.

  The orifice plate and the head body are joined using an adhesive.

  As the adhesive, a thermosetting type, UV curable type, heat, or UV combined type curable adhesive is used. After the adhesive is transferred to the orifice plate or the head body and bonded together, heat is applied or UV is applied. The adhesive is cured by irradiating light to complete the bonding.

For example, Patent Document 1 can be cited as a conventional example.
JP 2000-255069 A

  However, the conventional liquid discharge head has the following problems.

  When the adhesive is transferred to the orifice plate or the head main body and bonded, the transferred adhesive flows along the edge of the flow path wall of the head main body and flows into the flow path. The adhesive that has flowed in accumulates at the rear end of the flow path wall and has a shape like a match rod, and further blocks the flow path and affects the discharge.

  In addition, when there is a movable member on the heater, the gap between the heater and the movable member is filled with an adhesive, and the heater and the movable member do not function, and good discharge cannot be performed.

  There is a method to prevent the adhesive from flowing by changing the viscosity of the adhesive, but if the viscosity is increased, it is difficult to reduce the thickness of the adhesive itself. As a result, a large amount of the adhesive enters the end of the flow path, which also makes it impossible to perform good discharge.

  In the method of using UV curing type or UV and heat combined curing type adhesives, irradiating UV light to the adhesive in advance to start the curing reaction, and then transferring and pasting, the adhesion reliability As a result, the ink (ink resistance) deteriorates, and the ink oozes out to the adhesive interface between the orifice plate and the head main body and mixes colors or affects ejection.

  Accordingly, the present invention provides a liquid ejection head that ensures ejection failure and adhesion reliability due to an adhesive that flows in a large amount into a flow path when an orifice plate and a head body are bonded together and cured. With the goal.

  Each of the ink flow paths includes an energy element that generates energy used for ejecting ink, and a plurality of ink flow paths arranged in parallel to each other at a head body that opens at an end surface and a portion corresponding to each ink flow path. Adhesion of the part that is irradiated with UV light and the part that is not irradiated in the liquid discharge head that is bonded after transferring the UV curable adhesive or UV and thermosetting adhesive to the head body with the orifice plate that has the orifice communicating with the path It is characterized in that the agent is transferred and bonded.

(Function)
Create a part of the adhesive that has been exposed to a small amount of UV light (semi-lived part) and a part that has not been irradiated with UV light (raw part), and then transfer and paste them together.

  By doing so, the adhesive in the semi-finished part has a poor fluidity, and therefore blocks the flow of the adhesive in the raw part to some extent.

  Therefore, a large amount of adhesive can be prevented from flowing into the flow path.

  In addition, since the adhesive in the green part is present compared to the adhesive in which the entire transfer area is semi-finished, the adhesion reliability (ink resistance) can be improved.

  In the present invention, UV light is partially irradiated in advance to the adhesive used to join the orifice plate and the head body, and then transferred.

  The fluidity of the adhesive deteriorates in the part irradiated with UV light.

  Therefore, it was possible to prevent a large amount of adhesive from flowing into the flow path, perform good discharge, and greatly improve the yield of the liquid discharge head.

  In addition, since there are parts that are not irradiated with UV light, adhesive reliability (ink resistance) can be secured, and color mixing and ink leakage due to ink oozing out to the adhesive interface can be prevented. did it.

  In the present embodiment, as shown in FIG. 1, a photosensitive resin is patterned on a substrate (11) provided with an energy element for discharging a liquid to form a flow path wall and a liquid chamber frame.

  A head body (13) was formed by bonding an ink supply port and a top plate (12) forming a part of the flow path above the flow path wall with an adhesive.

  From the viewpoint of processability and ink resistance, the orifice plate (15) was formed with an orifice (14) by laser processing using polysulfone.

  Further, in order to prevent the adhesive from flowing into the orifice at the time of joining to the head body, a projection (16) is provided on the orifice plate joining surface.

  These protrusions were also formed by laser processing.

  As the adhesive, UV and thermosetting type cationic polymerization type epoxy adhesive was used.

  In order to completely cure the UV curable adhesive, it is necessary to irradiate a large amount of UV light through the orifice after the orifice plate and the head body are bonded together.

  Since this adversely affects the water repellent applied around the orifice, UV and thermosetting adhesives were used this time.

  FIG. 2 shows a method for forming an adhesive thin film.

  The PET film (22) is laminated on the Si wafer (21), and about 10 g of the adhesive (23) is applied on the PET film. The spin coater is rotated at 5000 rpm for 300 to 400 sec, and the thickness is about A 3 μm adhesive was formed.

  As shown in FIG. 3, the adhesive on the PET film was partially irradiated with UV light.

  A PET film with adhesive (34) was brought into close contact with a photomask (33) that partially cuts UV light, and UV light was irradiated from the PET film side.

A condenser lens (32) was attached to the tip of the UV fiber (31) so that the irradiation intensity of the irradiation area was uniform, and the UV light was irradiated under the conditions of an irradiation intensity of 20 mW / cm ² and an irradiation time of 5 to 10 Sec.

  FIG. 4 shows the photomask used this time.

  The part not irradiated with UV light was surrounded by the part irradiated with UV light, and each area irradiated with UV light was made as small as 5 × 5 μm.

  In addition, the mask pattern of a regular and larger area than the transfer area of the head body eliminates the need for transfer positioning between the adhesive after UV irradiation and the head body.

  Then, remove the PET film with adhesive (34) from the photomask, place the PET film with adhesive (34) on the orifice plate joint surface of the head body as shown in Fig. 5, and place the rubber roller (51) on the PET film. Were rotated under the conditions of a load of about 400 gf and a speed of about 10 mm / Sec.

  Then, the PET film was peeled off from the head body to complete the transfer of the adhesive.

  The thickness of the adhesive transferred to the head body is 1.5 μm, which is about half of the thickness spin-coated on PET.

  The head main body to which the adhesive is transferred is brought into contact with the orifice plate in a predetermined positional relationship, and thereafter, the pressure bonding is performed with a load of about 3 kgf.

  Finally, in order to accelerate the curing of the epoxy adhesive, it was cured by heating at 120 ° C. for 1 hour or more while maintaining the pressure-bonded state to complete the joining.

Configuration schematic diagram of ink jet head of embodiment of the present invention Schematic diagram of thin film formation of adhesive according to an embodiment of the present invention Schematic of irradiating UV light to the adhesive of the embodiment of the present invention Schematic diagram of a photomask for partially irradiating UV light to an adhesive according to an embodiment of the present invention Schematic of transferring an adhesive to a head body of an embodiment of the present invention Schematic configuration of conventional inkjet head

Explanation of symbols

11 Si substrate
12 Top plate
13 Head body
14 Orifice
15 Orifice plate
16 Orifice plate convex
21 Si wafer
22 PET film
23 Adhesive
31 UV optical fiber
32 condenser lens
33 Photomask
34 PET film with adhesive
51 Transfer roller

Claims (6)

A plurality of ink flow paths arranged in parallel to each other are provided with energy elements that generate energy used for ejecting ink, and each ink flow flows to a portion corresponding to each ink flow path. Orifice plate with orifice that communicates with the path
In the liquid discharge head that transfers UV and thermosetting adhesives and then bonds them together
Transfer the adhesive where there is a part irradiated with UV light and a part not irradiated,
A liquid discharge head characterized by bonding. Of the area of the transferred adhesive, the area of the adhesive irradiated with UV light is
The liquid discharge head according to claim 1, wherein an adhesive larger than an area of the adhesive not irradiated with UV light is transferred. Of the area of the transferred adhesive, the area of the adhesive irradiated with UV light is
The liquid discharge head according to claim 1, wherein an adhesive smaller than the area of the adhesive not irradiated with UV light is transferred. Of the adhesive area to be transferred, the adhesive area of the part irradiated with UV light
The liquid discharge head according to claim 1, wherein an adhesive having the same area of the adhesive in a portion not irradiated with UV light is transferred. 5. The liquid discharge head according to claim 1, wherein an adhesive in which a portion irradiated with UV light and a portion not irradiated in the transferred adhesive are regularly arranged are transferred.   The liquid discharge head according to claim 1, wherein the adhesive surrounded by the portion irradiated with the entire portion not irradiated with UV light is transferred.

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