JP3335736B2 - Ink jet recording head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus of the type in which ink droplets are caused to fly toward a recording medium, and more particularly to a recording apparatus for transferring heat energy.
The present invention relates to a recording device for recording using .

[0002]

2. Description of the Related Art An ink jet recording apparatus of a type in which a part of ink is rapidly vaporized by pulse heating and ink droplets are ejected from an orifice by its expanding force is disclosed in JP-A-48-9622 and JP-A-54-962. No. 51837 discloses this.

[0003] The most convenient method for the pulse heating is to pulsed current to the heating resistor, such inks
The jet recording device can print at high speed,
Large-scale and high-density collection of ink ejection nozzles in two dimensions
Line head formed by stacking, for example, 30 to 60 ppm
(Page / min) A4 full color printer line head
It is desired to provide such a device.

However, since this line head is manufactured from a monolithic LSI substrate using a Si wafer, the head is connected at the center of the line head. For this reason, it is necessary to keep the dot density to be printed at the connected central portion different from that of other portions, and the higher the dot density, the technically difficult this connection becomes.

An object of the present invention is to provide a method for easily connecting and assembling even if the dot density is increased, so that a long head such as a line head can be easily realized.

[0006]

An object of the present invention is to provide an ink jet recording head for ejecting ink droplets from an ejection surface in which orifices are linearly arranged using a plurality of ink ejection nozzles, wherein the ejection surface is , In the arrangement direction of the orifices
Two butt connected orifices with said orifices
The two orifices are formed by orifice plates.
Ink nozzles for each of the fiss plates
In all of the arrangement directions of the orifices,
Tilt at the same tilt angle in the direction toward the connection of the plate
This is achieved by an ink jet recording head characterized by being inclined . Here, it is preferable that the inclination angle is set so that the print dot density at the connection portion of the orifice plate is the same as the print dot density at the portion other than the connection portion. Further, it is preferable that the inclination angle is not less than 0.5 degrees and not more than 10 degrees. Here, it is preferable that the ejection of the ink droplets from the ejection surface is performed by a heating drive of the heating resistor.

[0007]

The ink jet recording head constructed as described above
(Hereinafter referred to as the head) is connected to the right half of the
The ink discharge nozzle is a little left side, the left half of ink ejection
Since the output nozzles discharge ink droplets to the right by the same inclination angle, the distance between the orifices at the connection part of the head is different from that of the other orifice on the recording paper traveling at a position away from the discharge surface (head surface) by, for example, 1 mm. Even if the distance is larger than the distance, the print dot density on the recording paper can be made uniform. This has a great advantage of facilitating the configuration near the connection portion between the left and right heads and the formation of the end faces and the assembling thereof.

[0008]

Embodiments will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an example of this embodiment. On the Si substrate 1 on which the driving LSI device 5 is formed, the heating resistor 2 that does not require a protective layer is integrally formed. On the Si substrate 1 , a common ink path 11, an individual ink path 10, The nozzle 8 and the orifice 19 are formed. The Si substrate 1 has a common ink passage 1
The passage 13 and the ink passage 15 in the frame 16 are connected by a connection hole 14 in the silicon substrate, and ink is supplied from the outside. The ink discharge nozzle 8, the heating resistor 2, and the individual ink passage 10 connected to the nozzle 8 are, for example, 360d in a direction perpendicular to the plane of FIG.
pi (dots / inch) and a line head of A4 size has 1 512 nozzles.
By connecting and assembling two / 2 size heads at the connection portion, an A4 full size line head of 3024 dots can be obtained . Such a configuration is
4-347150, Japanese Patent Application No. 5-68257
Driving LSI and protective layer for applying pulse current
Unnecessary thin film heating resistors on the same silicon substrate
Small, high-efficiency inkjet printer
Head realization. The present invention, this inn
An object of the present invention is to provide a head for facilitating connection and assembly at a connection portion of a jet print head . Hereinafter, a specific example thereof is shown in FIG.

FIG. 2 is a sectional view of the line head shown in FIG.
It is A 'sectional drawing and especially shows the vicinity of the connection part in the center. On the same frame 16, for example, two 1 / 2-size line heads having 1512 ink discharge nozzles 8 are connected and mounted in a straight line by abutting each other, and an A4 having 3024 ink discharge nozzles 8 is provided. The size of the line head. In the case of this embodiment, FIG.
As shown in FIG.
Is left to example 3 ° inclination with respect to the vertical direction of the ejection surface, the left side of the ink discharge nozzle 8, the vertical direction of the discharge surface
It is 3 ° slope on the right side of the (θ = 3 °).

In addition, as described above, all the nozzles for ink ejection
It is relatively easy to manufacture the orifice plate 9 so that the nozzle 8 is inclined by a small constant angle as follows. The first method is to subject a thick film resist (50 μm) coated on a Ni plate to oblique (θ = 3 °) exposure to 3
In this method, an orifice plate 9 is formed by forming an inclined nozzle column and Ni-plating the nozzle column to a thickness of 40 to 45 μm. In the second method, photosensitive glass, for example, glass ceramic PEG3 manufactured by HOYA Co., Ltd. is obliquely exposed to form an orifice plate 9, and the thickness in this case can be 40 to 100 μm.

The orifice plate 9 formed as described above and having the same size as, for example, a 5-inch wafer is positioned and bonded to the Si wafer 1 on which the partition walls 12 are formed.
Cut out to a 1/2 size line head and cut out the frame 16
FIG. 2 shows the connection and mounting. As shown in the drawing, when the ink discharge nozzles in the orifice plate 9 are inclined by 3 °, the tracks of the ink droplets ejected from the orifice plate 9 are also inclined by approximately 3 °. In this embodiment, since the dot density is 360 dpi, the width of the individual ink passage 10 is 50 μm, and the thickness of the partition 12 is 20 μm. Therefore, since the printing is performed at a position shifted by about 52 μm on the recording paper 18 traveling at a position 1 mm away from the orifice plate 9, the cutting position at the head end face may be a position separated by 52 μm from the original cutting position. become. That is, the thickness of the partition walls 12 forming the individual ink passages 10 at the connection portions had to be originally reduced to 20 μm / 2 = 10 μm.
A large margin can be provided up to 52 μm = 62 μm. This not only facilitates cutting of the end face of the head, but also ensures reliability against pressure fluctuations when bubbles are generated, and facilitates connection and mounting. Realistically, 62μ
It has been found that it is better to set the partition wall thickness of m to 50 to 55 μm to eliminate the influence of widening due to the intrusion of the adhesive.
The inclination angle θ is also determined by the orifice plate 9.
Θ = 0.5 because the minimum value of the partition wall thickness at the connection portion is allowed up to 20 μm depending on the distance between the recording paper 18 and the recording paper 18.
It is possible to select in the range of 10 to 10 °, preferably θ = 3 to 6 °. However, it is not preferable to make the inclination angle too large because it makes the production of the orifice plate 9 difficult.

The head shown in FIGS. 1 and 2 is a single-color head having a single nozzle row, but has a monolithic color head composed of a plurality of nozzle rows (Japanese Patent Application No. 5-901).
In the case of No. 23), it is needless to say that exactly the same technique can be applied.

Although the head shown in FIGS. 1 and 2 has a case where the heating resistor 2 is substantially perpendicular to the ink discharge direction, the same technique can be applied to a case where the heating resistor 2 is parallel. In this case, the individual ink passages are inclined by an appropriate angle of 0.5 to 10 ° as compared with the conventional type in which the direction of the individual ink passage is perpendicular to the orifice surface, and the two ink passages are opposed to each other. A / 2 size head may be assembled and mounted. In this type of head, a plurality of nozzle rows cannot be integrated, but a plurality of monochromatic line heads assembled in this manner can be combined into a color head.

[0015]

According to the present invention, even when two heads having orifice rows arranged at high density are assembled and mounted in a straight line to form one long line head, the connection at the connection portion thereof is reduced. The print dot density is not different from other parts, and the cutting, assembling and mounting of the head can be performed very easily.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of an ink jet recording head of the present invention.

FIG. 2 is a sectional view taken along line AA ′ of FIG.

[Explanation of symbols]

1 is a Si substrate, 2 is a heating resistor, 3 is a common electrode, 4 is an individual electrode, 5 is a drive LSI device, 6 and 7 are drive wiring electrodes, 8 is an ink discharge nozzle, 9 is an orifice plate, 10 Is an individual ink passage, 11 is a common ink passage, 12 is a partition, 13 is a common ink passage in the Si substrate, 1
Reference numeral 4 denotes a connection hole, 15 denotes an ink passage in a frame, 16 denotes a frame, 17 denotes a track of ejected ink, 18 denotes a recording sheet, and 19 denotes an orifice.

Claims (4)

(57) [Claims] 1. An orifice using a plurality of ink discharge nozzles.
Ink droplets are ejected from the ejection surface in which
An ink ejection recording head, wherein the ejection surface is formed by two orifice plates having the orifices connected to each other in a direction in which the orifices are arranged, and an ink ejection nozzle in each of the two orifice plates is In all of the arrangement directions of the orifices, in the direction toward the connecting portion of the orifice plate ,
An ink jet recording head which is inclined at one inclination angle . 2. The inclination angle is set such that a print dot density at a connection portion of the orifice plate is the same as a print dot density at a portion other than the connection portion.
2. The ink jet recording head according to 1. Wherein the angle of inclination, the ink jet recording head according to claim 1 or 2 or less 10 degrees 0.5 degrees. Wherein said discharging of ink droplets from the ejection face, the ink jet recording head according to any one of claims 1 to 3 for the heating operation of the heating resistor.