JPH11300976A - Liquid ejection head - Google Patents

Abstract

(57) [Problem] To provide a liquid ejection head capable of performing good recording for a long time without corroding or deforming a member in contact with ink even when highly corrosive ink is used. thing. A discharge port for discharging a liquid, a liquid flow path communicating with the discharge port, and energy generation arranged corresponding to the liquid flow path and generating energy used for discharging the liquid. And a liquid discharge head having the element.
The orifice plate used to form the discharge port is made of a Ni-Pd alloy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid discharge head which uses an alloy having excellent ink corrosion resistance in a liquid discharge head for generating bubbles by heat energy or the like and discharging a desired liquid by an electromechanical transducer.

[0002] The present invention also relates to a facsimile having a printer, a copying machine, a communication system, and a printer for recording on a recording medium such as paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics and the like. The present invention can be applied to an apparatus such as a word processor having a section, and further to an industrial recording apparatus combined with various processing apparatuses.

In the present invention, "recording" means not only giving an image having a meaning such as a character or a figure to a recording medium, but also giving an image having no meaning such as a pattern. means.

[0004]

2. Description of the Related Art As a conventional ink jet recording apparatus, recording head and recording unit integrated with an ink tank, a recording unit utilizing thermal energy or an electromechanical transducer is known.

In particular, an ink jet recording head that discharges a recording liquid by using thermal energy can perform high-resolution recording because discharge ports for discharging ink can be arranged at a high density. It has advantages such as easy downsizing as a whole, and has already been widely used.

A main body member of the ink jet recording head includes a liquid chamber for storing ink, an ink flow path, and a discharge port forming member (hereinafter, referred to as an orifice plate). An ink discharge port is provided so as to communicate with the road.

The orifice plate is usually joined to a top plate (liquid ejection head main body side) after ink ejection ports are formed.

Hitherto, Ni has been used for the orifice plate because of its good ink corrosion resistance.

Further, in a liquid discharge head, a method of providing a movable member having a valve function in the head as a method for improving the liquid discharge efficiency, discharge force, discharge speed, and landing accuracy on a recording medium. Although disclosed in Japanese Patent Application Laid-Open No. Hei 9-11471, since the movable member is also in contact with the ink,
For the same reason and simplicity in the production method, Ni was often used.

[0010]

However, in recent years,
The alkalinity of the ink for an ink jet printer has increased, and corrosion has started from a portion in contact with the ink, thus causing a problem that Ni is eluted.

Japanese Patent Publication No. 06-0063377 discloses Ni
Discloses a method of forming a noble metal coating on Ni for the purpose of improving the ink corrosion resistance of Ni.

Gold, platinum and the like are chemically stable and have excellent ink resistance. However, if the film is thin, has pinholes, or if the quality of the noble metal film is poor to some extent, the Ni layer may be an ink. You will be exposed to

[0013] Ni is not stable with respect to recent corrosive ink.

Therefore, the noble metal film must be thickened to some extent, but there is a problem that the cost is increased accordingly.

Further, when the noble metal film is partially peeled, ink enters, the underlying Ni is eroded, and the peeling further proceeds.

Japanese Patent Application Laid-Open No. 9-57958 discloses S
A method for forming an alloy based on n-Ni and added with a metal arbitrarily selected from Cu, Pd, Au, and Ag is disclosed.

However, the ink used in this publication is a hot melt ink, and the alkali ink in recent years has higher corrosiveness.

Further, this publication mainly describes an improvement in corrosion resistance of a joint.

For example, the assumed thickness of the joint is 500 μm, and the target value of the corrosion rate is 0.14 μm / day or less.

However, in recent years, as the image quality of the ink jet printer has been improved, the density of the nozzles has been increased, and the area of the ink discharge ports and the arrangement pitch have been reduced.

Therefore, the thickness of the orifice plate is also 50
It becomes thinner within 0 μm, and the corrosion rate does not satisfy the required head life.

Further, if the edge of the ink discharge port is deformed due to corrosion, the flight direction of the ink droplet is not stable, and good recording cannot be performed.

Further, the thickness of the movable member having a valve function disposed in the head is as thin as several μm to several tens μm, and the movable member itself disappears during the period of use of the printer at the above-mentioned corrosion rate.

The present invention has been made in view of the above-mentioned problems of the prior art, and even when a highly corrosive ink is used, members in contact with the ink are not corroded or deformed. It is an object of the present invention to provide a liquid discharge head capable of performing good printing for a long time.

[0025]

In order to achieve the above object, the present invention provides a discharge port for discharging a liquid, a liquid flow path communicating with the discharge port, and a liquid passage corresponding to the liquid flow path. An orifice plate used for forming the discharge port is made of a Ni-Pd alloy in a liquid discharge head having an energy generating element for generating energy used for discharging a liquid. It is characterized by.

The present invention also provides a discharge port for discharging a liquid,
A liquid flow path that communicates with the discharge port, and an energy generating element that is provided corresponding to the liquid flow path and that generates energy used for discharging the liquid, based on the generated energy. In a liquid discharge head that discharges liquid by the generation of bubbles, a movable member having a valve function provided in the liquid discharge head is made of a Ni-Pd alloy.

The present invention further provides a discharge port for discharging a liquid,
A liquid flow path communicating with the discharge port, and a liquid discharge head having an energy generating element disposed to correspond to the liquid flow path and generating energy used for discharging the liquid; The orifice plate used to form the discharge port and the movable member having a valve function provided in the liquid discharge head are made of a Ni-Pd alloy.

In the first and third aspects of the present invention,
The liquid discharge head may be a liquid discharge head that discharges liquid by generating bubbles based on energy generated by the energy generating element.

By configuring the present invention as described above, the liquid ejecting head of the present invention does not corrode or deform members in contact with the ink even when highly corrosive ink is used. , It is possible to perform good recording.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the weight percent of Pd in a Ni-Pd alloy used for an orifice plate is preferably 38 wt% or more, as shown by the test results in Examples described later. In actual use conditions of a liquid discharge recording apparatus (such as an ink jet printer) using a liquid discharge head, Ni-P in which the weight% of Pd
By using an orifice plate made of a d alloy, it is possible to satisfy the life required for a discharge head of a recording apparatus and good liquid discharge recording performance during use.

In the present invention, the weight percentage of Pd of the Ni—Pd alloy used for the movable member having a valve function provided in the liquid discharge head is 5 wt% as shown in the test results of the examples described later. It is preferable that it is above. The problem with the movable member that fulfills the valve function is not the slight deformation due to corrosion of the discharge port edge such as the orifice plate, but the problem of the disappearance of the movable member itself.
In other words, the function of the movable member has almost no effect on the life of the liquid discharge recording apparatus as long as the movable member does not disappear even if its thickness is reduced. That is, the allowable corrosion rate of the movable member can be increased as compared with the orifice plate, and a preferable weight% of Pd of the Ni-Pd alloy to be used is selected in consideration of the thickness of the movable member and the life of the head. be able to.

[0032]

The present invention will be described in more detail with reference to the following examples.

Embodiment 1 FIG. 1 is a process chart showing a method for manufacturing an orifice plate. First, using photolithography technology, the substrate 1
A resist 12 is formed at a predetermined position on the substrate 1. (Figure 1
(A) Next, a Ni-Pd alloy 13 is formed on the substrate 11 on which the resist 12 has been formed by using an electroforming method. (FIG. 1B) Thereafter, the resist 12 and the substrate 11 are sequentially peeled from the Ni—Pd alloy 13, thereby forming the discharge ports 14.
(FIG. 1 (c)) Although one embodiment of the orifice plate has been described above, the movable member can be formed by using the same method only by changing the resist pattern.

Here, the plating method of the above-mentioned Ni-Pd alloy will be described in detail. FIG. 2 is a perspective view showing an apparatus used in a plating step in the method for manufacturing the orifice plate shown in FIG.

As the plating solution, a solution containing diamine palladium dichloride, nickel hydroxide, ammonium phosphate, 4-oxo-pentanoic acid, saccharin, and ammonium hydroxide was used.

As to the method of applying electrolysis at the time of electrodeposition, an electrode in a plating solution is connected to the anode side, and the substrate 11 is connected to the cathode side.

The plating temperature is 50 ° C. and the current density is 5 A / d
It was m ^2.

Next, in order to determine the relationship between the Pd weight% of the Ni—Pd alloy and the corrosion resistance of the ink, a weight reduction test was performed using the test piece prepared by the above-described method.

The ink used for the evaluation was a yellow ink of a Canon color BJ cartridge Bc-61, and a test piece (10%) of pure Ni and a Ni-Pd alloy was added to 100 ml of the ink.
mm × 7 mm), and stored at 100 ° C. as an accelerated test.

In this test, the weight loss of the test piece before and after storage was measured and converted into a corrosion size (film thickness).

FIG. 3 shows the amount of corrosion (reduced film thickness) of the five types of test pieces with respect to the immersion time.

Generally, the reaction rate (corrosion rate) doubles every time the temperature rises by 10 ° C., so that the point A at 100 ° C. for 3 days is about one year (384 ° C.) at room temperature (30 ° C.).
Day).

The life required of the ink jet cartridge of the ink jet printer is at least one year.

From this, it is considered that if the amount of corrosion is small in the point A line at 100 ° C. for 3 days, the life of the ink jet cartridge and its performance are satisfied.

From FIG. 3, it can be seen that the weight percentage of the Ni—Pd alloy having a corrosion amount of 1 μm or less in the line at point A at 100 ° C. for 3 days is 38 wt% and 62 wt%.

That is, the weight percent of the Ni—Pd alloy is 38%.
If the content is not less than wt%, it is considered that the ink cartridge satisfies practically sufficient liquid discharge recording performance.

Next, a Ni-Pd alloy suitable for a movable member having a valve function provided in the head will be described.

The materials used for the orifice plate are:
There is a problem that the discharge amount changes due to slight corrosion of the discharge port edge. However, disappearance of the movable member becomes a problem rather than slight corrosion.

That is, with respect to the life of the BJ cartridge,
Even if the thickness of the movable member is reduced, its function is not affected if it does not disappear.

Therefore, the corrosion rate of the movable member may be higher than that of the orifice plate.

For example, if the thickness of the movable member is 10 μm, if the weight percent of Pd in the Ni—Pd alloy is 24 wt%, FIG. 3 shows that even after 3 days at 100 ° C., 4 μm does not elute and disappear. .

When the thickness of the movable member must be reduced in design, the weight percentage of Pd of the Ni—Pd alloy is
Should be increased. For example, when the thickness of the movable member is 5 μm, if the weight% of Pd of the Ni—Pd alloy is 38 wt%, only 1 μm is eluted after 100 ° C. for 3 days from FIG. I understand.

That is, in the movable member, the weight% of Pd of the Ni-Pd alloy may be selected in consideration of the thickness.

It is clear from FIG. 4 that even if Pd is contained even slightly, the corrosion rate of the Ni—Pd alloy is lower than that of pure Ni, but in the present invention, the weight percentage of Pd in the movable member is 5 wt% or more. I found that there would be no problem. This will be described in detail below.

FIG. 5 is a graph showing the correlation between the thickness of the movable member and the refill frequency which is a characteristic of the head. In general, a configuration in which a movable member is provided in a head is configured to suppress a back wave in a flow path and to enable high-frequency printing (Japanese Patent Application Laid-Open No. Hei 9-11471). Therefore, the refill frequency changes depending on the manner of movement of the movable member, and high-frequency driving may not be realized. As a result of confirming the relationship between the thickness of the movable member and the refill frequency in FIG. 5, when the thickness of the movable member exceeds 20 μm, the refill frequency starts to decrease, and when the thickness of the movable member becomes 30 μm, the refill frequency decreases to half. I knew it would.

Therefore, it was found that the performance of the head was reduced when the thickness of the movable member was set to 30 μm. On the other hand, from FIG. 4, the corrosion rate of pure Ni is 8.5 μm / day, and Ni-P
When the Pd weight% of the d alloy is 5 wt%, the corrosion rate is 7.
0 μm / day, the thickness at which the thickness of pure Ni disappears is 25.5 μm,
If the Pd alloy has a Pd weight% of 5 wt%, the thickness at which the thickness disappears is 21.0 μm.
As described above, if the movable member remains to such an extent that it does not disappear, there is no problem in the function of the head. Therefore, if the remaining thickness is at least 1 μm, the thickness of pure Ni is 26.5 μm.
If the Pd weight% of the m-Ni-Pd alloy is 5 wt%, the thickness is 22 μm. Furthermore, the tolerance of electroforming is ± 2μ.
Considering m, the thickness of pure Ni is 30.5 μm, and the thickness of Pd by weight of the Ni—Pd alloy is 5 wt% is 26 μm.

That is, it is understood that the thickness of pure Ni must be 30 μm or more, and that the thickness does not satisfy the function of the ink jet cartridge.

On the other hand, when the Pd weight% of the Ni—Pd alloy is 5 w
It can be seen that t% does not affect the function of the ink cartridge because the thickness is 30 μm or less.

Example 2 Next, Ni and Ni-P for various alkaline inks were used.
In order to compare the corrosion resistance of the d alloy, a weight loss test was performed using a test piece.

The inks used for the evaluation were black and color BJ cartridges of Canon Black BJ Cartridge Bc-60.
A test piece (10 mm × 7 mm) of Ni and a Ni—Pd alloy was immersed in 100 ml of each of the four types of inks of cyan, magenta, and yellow in a cartridge, and allowed to stand at 120 ° C. and 2 atm for 10 hours as an acceleration test.

The weight loss of the test piece before and after standing was measured,
Table 1 shows the results converted to the corrosion dimensions (film thickness).

The Ni-Pd alloy used in this example had a Pd weight percentage of 62 wt%.

The four types of inks are alkaline inks having a pH of 8.5 or more.

[0064]

[Table 1] Note: ○: No dissolution △: Dissolution, reduced film thickness α <3 μm ×: Dissolved, reduced film thickness α> 3 μm

As a result, in the three color inks, the Ni test pieces dissolved and the weight (film thickness) was reduced.

In particular, the yellow ink and the magenta ink are strongly dissolved.

This is due to subtle differences in additives, dyes and the like.

Further, it is considered that the luster of the metal surface observed before the test disappeared after the immersion, and that corrosion proceeded from the surface.

However, the weight of the Ni-Pd alloy test piece did not decrease in any of the inks.

Further, the metallic luster of the surface was maintained unchanged before and after immersion.

That is, it can be seen that the use of the Ni-Pd alloy significantly improved the corrosion resistance to various inks.

Embodiment 3 In this embodiment, Ni-Pd containing 62% by weight of Pd was used.
An orifice plate made of an alloy was prepared.

The thickness of the orifice plate is 15 μm, and a circular discharge port having a diameter of 20 μm has an arrangement pitch of 40 μm.
The number m is 300.

FIG. 6 schematically shows a process of assembling the orifice plate to a liquid discharge head.

As shown in FIG. 6, the orifice plate 6
1 is joined to the face surface of the liquid discharge head in which the liquid flow path 62, the element substrate 63 and the top plate 64 are formed, and then assembled into an ink cartridge, thereby completing the liquid discharge head as shown in FIG. Was.

If dust or ink adheres to the face of the liquid ejection head orifice plate, the ink droplets are attracted during ejection of the ink droplets and the flying direction of the droplets is disturbed, so that good recording cannot be performed.

As a countermeasure, a method of wiping dust or ink attached to the face of the orifice plate with a blade is often used.

However, if the orifice plate is made of a soft material, the orifice plate and the ink discharge ports are deformed or damaged.

When the orifice plate is coated with a coating, problems such as peeling of the coating and flawing to expose the inner layer of the coating occur.

In this embodiment, the orifice plate is made of an alloy and has sufficient strength against wiping.

Even if it is slightly damaged, corrosion does not proceed from there.

That is, handling in the mass production process is facilitated.

Further, unlike the film coating, since the whole is a corrosion-resistant layer, the corrosion resistance is maintained even if the orifice plate is made thin.

Therefore, the cost is low.

In the above-described embodiment, an example in which the orifice plate is applied to an edge shooter type head as shown in FIG. 6 has been described. However, a side shooter type head in which discharge ports are arranged on a heat generating portion is described. It can also be applied to

Embodiment 4 In this embodiment, Ni-Pd containing 62% by weight of Pd was used.
A movable member made of an alloy was manufactured.

The movable member has a thickness of 5 μm and a width of 20 μm.
300 μm slits are arranged at an arrangement pitch of 40 μm.

As shown in FIG. 8, the orifice plate 6
1 was bonded to the face surface of the liquid discharge head on which the liquid flow path 62, the element substrate 63, the top plate 64, and the movable member 81 were formed, thereby completing the liquid discharge head as shown.

As shown in FIG. 8, the movable members 81 are arranged so that the slits of the movable members correspond to the liquid flow paths 62.

FIG. 8 shows an example of a movable member provided in the flow path. The shape and position of the movable member are not limited to those described above.
This is effective when all or a part of the movable member is in contact with the ink.

In the present embodiment, since the movable member is disposed in the flow path, the movable member is always in contact with the ink. In addition, the slit shape of the movable member is reduced in size and thickness to increase the density of the nozzles.

Therefore, a Ni-Pd alloy having high ink corrosion resistance as in the present invention is very effective.

Further, it is resistant to scratches, and corrosion does not progress from the scratches.

That is, handling in the mass production process is easy.

[0095]

According to the present invention, by using an orifice plate made of a Ni-Pd alloy in a liquid discharge recording head, even when highly corrosive ink is used,
There was no deformation of the orifice plate and the discharge port, the stability of the flying direction of the ink droplets was secured, and good recording could be performed.

Further, it is resistant to abrasion due to wiping or the like, and even if it is scratched, corrosion does not proceed from the scratch.

In the liquid discharge recording head, Ni-
By using a movable member made of a Pd alloy, even when ink having strong corrosiveness was used, the movable member could continue to maintain a predetermined function without disappearing.

Therefore, the long-term reliability of the ink jet printer was significantly improved.

[Brief description of the drawings]

FIG. 1 is a process chart showing a method for manufacturing an orifice plate.

FIG. 2 is a perspective view showing an apparatus used in a plating step.

FIG. 3 is a graph showing the relationship between the immersion time and the amount of corrosion (in terms of reduced film thickness) of each test piece.

FIG. 4 is a graph showing the relationship between the weight percentage of Pd in a Ni—Pd alloy and the corrosion rate.

FIG. 5 is a graph showing a relationship between a thickness of a movable member and a refill frequency.

FIG. 6 is a schematic view schematically showing a process of assembling an orifice plate to a liquid discharge head.

FIG. 7 is a schematic view of the liquid discharge head.

FIG. 8 is a schematic view schematically showing a process of assembling an orifice plate to a liquid ejection head on which a movable member is arranged.

[Explanation of symbols]

 Reference Signs List 61 orifice plate 62 liquid flow path 63 element substrate 64 top plate 65 discharge port 73 ink cartridge 74 TAB tape 81 movable member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Junji Tatsumi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Ken Ikegame 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside the corporation

Claims (9)

[Claims] 1. A discharge port for discharging a liquid, a liquid flow path communicating with the discharge port, and energy that is disposed corresponding to the liquid flow path and generates energy used for discharging the liquid. In a liquid ejection head having a generating element,
A liquid discharge head, wherein the orifice plate used to form the discharge port is made of a Ni-Pd alloy. 2. The Ni—Pd alloy has a Pd weight percentage of 3%.
The liquid discharge head according to claim 1, wherein the content is 8 wt% or more. 3. A discharge port for discharging a liquid, a liquid flow path communicating with the discharge port, and energy that is disposed corresponding to the liquid flow path and generates energy used for discharging the liquid. A liquid discharging head for discharging a liquid by generating bubbles based on generated energy, wherein a movable member having a valve function disposed in the liquid discharging head is made of a Ni-Pd alloy. A liquid ejection head characterized by the above-mentioned. 4. The Ni—Pd alloy has a Pd weight percentage of 5%.
The liquid ejection head according to claim 3, wherein the content is not less than wt%. 5. The liquid discharge head according to claim 1, wherein the liquid discharge head is a liquid discharge head that discharges liquid by generating bubbles based on energy generated by the energy generating element. 6. A discharge port for discharging a liquid, a liquid flow path communicating with the discharge port, and energy that is arranged corresponding to the liquid flow path and generates energy used for discharging the liquid. In a liquid ejection head having a generating element,
An orifice plate used to form the discharge port, and a movable member having a valve function provided in the liquid discharge head is made of a Ni-Pd alloy. 7. The Ni-based metal used for the orifice plate.
The liquid ejection head according to claim 6, wherein the Pd alloy has a Pd weight percentage of 38 wt% or more, and the Ni-Pd alloy used for the movable member has a Pd weight percentage of 5 wt% or more. 8. The liquid discharge head according to claim 6, wherein the liquid discharge head is a liquid discharge head that discharges liquid by generating bubbles based on energy generated by the energy generating element. 9. A liquid discharge recording apparatus comprising the liquid discharge head according to claim 1. Description: