JPS5839069B2 - Inkjet head manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an on-demand inkjet head, and particularly to a method for manufacturing the same.

The so-called ink-on-demand inkjet recording device uses the deflection of a piezo element to pressurize ink in a pressure chamber and eject ink droplets from a nozzle.It has a simple mechanism, uses low power, and can print on plain paper. Recently, it has received particular attention as an impact recording device.

FIG. 1 shows an example of such a head for an inkjet recording device, in which a is a plan view and b is a cross-sectional view.A shallow groove 2 is provided in a substrate glass 1, and a diaphragm glass 3 is bonded to this groove 2. This groove 2 is connected to a series of ink supply chambers 7.
, ink pressure chamber 4, ink communication 5, and nozzle/l/6.

In this example, these are multi-heads composed of seven sets within - heads.

A piezo element 8 is bonded to the diaphragm glass 3 at a portion corresponding to the ink pressure chamber 4.

Reference numeral 9 denotes an ink supply pipe through which the ink supply chamber T, ink pressure chamber 4, ink passage 5, and nozzle/L/6 in the head are filled with ink from an ink tank (not shown).

When a voltage pulse is applied to the upper and lower electrodes of the piezo element 8 in this state, the piezo element 8 is bent by the contraction of the piezo element 8 and the action of the diaphragm glass 3, and pressurizes the ink in the ink pressure chamber 4.

The pressure of the pressurized ink is transmitted through the ink passage 5 to the nozzle 6, and an ink droplet is ejected from the nozzle.

In this way, ink droplets can be ejected by applying a voltage pulse of 8 Vc to the piezo element as needed, and a head with seven nozzles 6 concentrated in a vertical line as shown in the figure can be used as a recording device as shown in Figure 2. It can be summarized.

That is, the head 10 is arranged to face the recording paper 12 fed along the platen 11, and is applied as a serial printer that prints dots while moving in the direction of the arrow 13.

The present invention provides a manufacturing method advantageous for mass production of the above-mentioned flat plate bonded type inkjet recording head, and will be described in detail with reference to the drawings.

FIG. 3 is a plan view of a raw material substrate glass 14 according to an embodiment of the present invention, in which a section 16 surrounded by an arrow 15 is 1
This will be the substrate glass for this head.

As described above, the substrate glass 16 is formed with grooves serving as flow paths, and in this embodiment, the flow path grooves are formed by photoetching.

That is, chromium (base) and gold are deposited on the entire surface of the raw material substrate glass 14, and then a resist is applied, and exposed using a mask with desired grooves formed thereon, thereby etching the gold and chrome.

The remaining gold and chromium serve as a mask and are immersed in an etching solution containing hydrofluoric acid as a main component to form desired channel grooves.

After that, the remaining gold and chromium are peeled off, and the groove formation in the raw material substrate glass 14 is completed.

Here, one section of the raw material substrate glass 14 becomes one sheet of substrate glass 16, so in the illustrated case, there are 15 sheets of substrate glass 16.
groove formation is performed at the same time.

That is, in the exposure process, the entire surface of the raw material substrate glass 14 is simultaneously exposed, and the same is true in the etching process, resulting in a productivity 15 times higher than in the case of performing the same on each individual substrate glass 16Vc.

The details of the channel grooves formed here are shown in FIG. 4.

One section surrounded by a broken line 15 constitutes one substrate glass 16, and the diagonal line portion 210 is a groove, and this groove 210 has an ink supply chamber 20, an ink pressure chamber 17, an ink passage 18, and a nozzle. It will be 19.

Therefore, the characteristics of this channel groove 210 are that the adjacent substrate glass part and the nozzle part are formed so that the nozzle and the ink supply chamber side are also bordered by the ink supply chamber, and that the connection part of the ink supply chamber is A large number of islands 21 are left and are connected by a large number of thin grooves.

The effects produced by this feature will be described later.

Now, the raw material substrate glass 14 in which the channel grooves are formed in this way
Although not shown, they are bonded to the raw material diaphragm glass having the same flat shape, and piezo elements are bonded to the respective portions facing the ink pressure chambers 17.

After that, the broken line 15Vc of the raw material substrate glass 14 is cut using a thin (0.1 to 0.2 mm) diamond blade.
cut along and separated as individual heads.

These can be completed as a head by wiring lead terminals for applying voltage pulses to the ink supply tube 9 and each piezo element shown in FIG. 1.

FIG. 5 shows the pattern of cutting by the diamond blade 24Vc. If there is no island 21 in the cutting at the ink supply chamber 20 in FIG. Groove 21 between raw material diaphragm glass 23
This groove 21 exists in almost the entire area to be cut.

When cutting such a part, the facing surface of the groove 210 vibrates unstablely and the corner after cutting is chipped, and moreover, the small chip gets into the groove, and when this is completed as a head, it will be damaged. The chips reach the nozzle, clogging the nozzle, and becoming a major cause of yield deterioration.

However, in this embodiment, since the island 21 is particularly provided, the cut is shown in FIG. 5, and there is only a thin groove, and the cut surface is almost a rigid body, resulting in a stable cut surface with almost no chipping. Therefore, no foreign matter was seen entering the groove, and the cause of nozzle clogging in case a could be eliminated.

Furthermore, the effect of providing this island 21 is that it acts as a filter when the head is completed.

That is, even if a foreign object larger than the narrow straight path 22 attempts to enter from the ink supply pipe, it will be blocked by this portion, thereby preventing clogging of the nozzle.

Therefore, it is desirable that the cross-sectional area of the channel groove 22 in this portion be equal to or smaller than that of the nozzle 19.

Next, the cutting by the nozzle 19 is a small groove cut by the nozzle 19, and this can perform stable cutting like the cutting b mentioned just now.

FIG. 6 shows a double-sided nozzle inkjet head in which channel grooves 26 and 27 are formed around a substrate glass 25, and diaphragm glasses 28 and 29 are bonded to both sides. It is self-explanatory that it can be applied to heads.

FIG. 7 shows yet another type of head, in which the substrate glass 3
A groove 31 is formed in 0, and a diaphragm glass 32 and a piezo element 33 are bonded to the groove 31.
There are parts such as a nozzle 36.

34 is an ink supply pipe through which ink is supplied from an ink tank.

The nozzles 36 are arranged horizontally at regular intervals as shown in the figure, and this type of head is applied to a recording device as shown in FIG.

The head 31 is placed with its longitudinal direction parallel to the axis of the platen 38, and records on the recording paper 39 like a line printer while vibrating as indicated by an arrow 40.

In this type of head, a large number of grooves in the substrate glass 43 are simultaneously formed by photoetching on the raw material substrate glass 41 shown in FIG. 9 in the same manner as shown in FIG. The heads can be made into individual heads by simply dividing them, that is, they only need to be cut in parallel straight lines, and the cutting process is easier than in the previous embodiment.

FIG. 10 is a detailed view of the hatched part of the groove 31 of this raw material substrate glass 41, and as shown in the figure, the ink pressure chamber 35, nozzle 36
, the groove 31 is formed by the ink supply section 44, and the fourth
As shown in the figure, adjacent glass substrates 43 are connected to each other through nozzles and ink supply units.

Therefore, it can be divided into individual pieces simply by cutting with a thin diamond blade.

Since the nozzle 36 is a narrow groove and the ink supply section 44 is also a slightly thicker groove, cutting stability is good.

(This is the same as the cutting conditions described above in Figure 5.

) Although the embodiments of the present invention have been described above, the present invention is not limited to the head and its manufacturing method described in the embodiments. For example, the head may be made of a metal plate such as ceramic or stainless steel in addition to glass. Alternatively, the channel grooves do not necessarily need to be formed by photoetching, and may be formed by other methods.

There are no other limitations on the number of nozzles or the shape of the channel grooves.

As explained in detail above, according to the inkjet head manufacturing method of the present invention, a large number of heads are simultaneously processed by force and cut and separated into individual heads near the final process, making it an especially excellent manufacturing method for mass production. It provides:

[Brief explanation of the drawing]

Fig. 1 shows an example of an inkjet head, Fig. 2 shows a recording device using the inkjet head, Fig. 3 is a plan view of a head component according to an embodiment of the present invention, Fig. 4 is a detailed view thereof, and Fig. 5 6 is an example of another inkjet head to which the present invention can be applied; FIG. 7 is an example of still another inkjet head to which the present invention can be applied.
FIG. 8 is the recording device, FIG. 9 is a plan view of one component when the head of FIG. 7 is manufactured by a method according to an embodiment of the present invention, and FIG. 10 is a detailed view of FIG. 9. . 1...Substrate glass, 2...Groove, 3...
...Diaphragm glass, 8...Piezo element, 1
4... Raw material substrate glass, 21... Island,
24...Diamond blade.

Claims (1)

[Claims] 1 One flat plate provided with a shallow groove and the other flat plate are adhered, and the groove forms a series of ink supply chambers, ink pressure chambers,
In an on-demand inkjet head that consists of ink channels, nozzles, etc., a plurality of head channel grooves are provided on a single flat circle, and this flat plate is glued to another flat plate and then cut and separated. A method for manufacturing an inkjet head, characterized in that each head is made into individual heads.