JPS6235764A - Recording method - Google Patents

Abstract

PURPOSE:To improve picture quality and to increase speed by setting the extent of subscanning-directional movement to the integer multiple of the extent of movement a half as large as the intervals of nozzle holes perpendicular to a main scanning direction. CONSTITUTION:Plural (N) nozzle holes (ink jet hole) 2 are arranged at intervals P on the jet surface 1A of a multihead nozzle 1 so as to obtain dot intervals of the multihead nozzle 1 for obtaining the dot interval of 16dots/mm. The intervals P of the nozzle holes 2 are set to a value a half as large as desired dot density, i.e. 8nozzles/mm. The nozzle head 1 is driven while making a main scan as shown by an arrow 3 and then the head 1 makes a fine subscan by a half as large as the nozzle hole pitch P as shown by an arrow 5.

Description

Detailed Description of the Invention [Prior Art] In order to increase the speed of an inkjet recording device that forms images by ejecting ink droplets from nozzle holes with a minute diameter, a plurality of nozzle holes are arranged. using a multi-nozzle head.

Devices that record multiple scanning lines simultaneously are well known.On the other hand, there is a growing desire to reproduce high-definition images by increasing dot density in order to improve image quality. .

Conventionally, in the case of a multi-nozzle head, the density of dots is equal to the arrangement density of nozzle holes, so in order to obtain a high-definition image, it was necessary to increase the nozzle density. So, for example, if you want to obtain a high-definition image of 16 dots per meal,
A head with a high density arrangement of 16 nozzle holes per track layer is required, and the nozzle hole edge is 62-5 #L■. However, manufacturing a head with a large number of multi-shell nozzle holes arranged at such a pitch requires advanced technology and cost, and the yield is extremely low. It has been difficult with today's technology to simultaneously achieve high speed and high definition.

[Problems to be Solved by the Invention] The present invention focuses on and attempts to solve the above-mentioned conventional problems, and achieves high-density recording using a multi-nozzle head whose density is not very high. This makes it possible to record at high speed.

[Means for Solving the Problems] In order to solve these problems, the present invention provides a method for relatively scanning and moving a recording head having a plurality of nozzle holes for ejecting liquid and a recording member. In the recording method, the scanning consists of a main scanning and a sub-scanning in a direction perpendicular to the main scanning direction, and the amount of movement in the sub-scanning direction is equal to the amount of movement of the nozzle hole in the direction perpendicular to the main scanning direction. It is set as an integral multiple of the movement amount of 1/2 of the interval P.

[Operation] In the recording apparatus configured as described above, dots are formed by main scanning from right to left using a multi-nozzle head in which N nozzle holes are arranged at intervals of P, and then dots are formed by main scanning from right to left. After moving the head in the sub-scanning direction perpendicular to the main-scanning direction, the main scan returns from left to right in the opposite direction to the previous main-scanning direction to create a dot between the rows of dots formed earlier. By forming the dots, the dot formation interval is reduced to 172P.
This makes it possible to make images with high definition and to form such images at high speed.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail and specifically with reference to the drawings.

FIG. 1 shows a preferred example of a multi-nozzle head used in the final step 151. In this example, the multi-head nozzle 1 is used to obtain a dot spacing of 16 dots/111. On the ejection surface IA, multiple a (N) nozzle holes (ink ejection holes) 2 were arranged at intervals P to be described later. Furthermore, the diameter d of the nozzle hole 2 is a value suitable for a dot density corresponding to the diameter of the ink dots on the recording paper 2 of 16 dots per serving (density at which 16 dots are formed between each dot in both the vertical and horizontal directions). I set it like this.

Note that the value of the diameter d of the nozzle hole 2 varies depending on the characteristics of the ink, the bleeding rate of the recording paper, etc., but in the case of this example, by setting d to 20 liters, the diameter of the recording paper (not shown) is approximately You will get 80 closing dots.

Historically, the spacing P between the nozzle holes 2 is -1/2 of the above-mentioned desired dot density. That is, it was set to a value corresponding to 8 nozzles/m-. Therefore, the interval P between the nozzle holes 2 is! 25
u, become Peng. In this example, the number N of nozzle holes 2 is 128.

Next, the recording operation according to the present invention using such a multi-nozzle rad l will be explained with reference to FIG.

Here, the nozzle rad l is driven while being main-scanned in the direction of arrow 3 to form dots 4 on recording paper (not shown), but the driving frequency at this time is ! 6
It corresponds to the recording density of dot/I, and the operation speed is
The driving frequency when QQma /sec is 1,6
It becomes KHz. However, due to the main scanning of the lever from right to left (hereinafter referred to as forward scanning), the dot rows 4-1, 4-2
．． . . , 4-128 are recorded on the recording paper 10.

When this forward scanning in the three directions of the arrow is completed, the primary head l
is 1/2 of the nozzle hole pitch P described above in the direction of arrow 5.
In this embodiment, the sub-scanning distance is 82.5 gm, in which minute sub-scanning is performed by a scanning means (not shown).

Thereafter, the head 1 continues to perform main scanning (hereinafter referred to as backward scanning) in the direction of the arrow 6, contrary to the forward scanning, and is driven at the same driving frequency to form a dot row? −
1,7-2,...? -128 is recorded.

Thus, when the reciprocating main scan is completed, the head l
is sub-scanned by (NXP-P/2) in the direction of arrow 8, and the recording operation -1- is repeated.

In the case of this embodiment, since there are N-128 and P=125u, the sub-scanning amount for that - time is 15.9375μ.

Thus, the number of dot rows recorded along the direction of the head 1 when the head 1 completes one reciprocation is 128 x 2
= 258, and by performing the reciprocal recording, twice the number of nozzles N dot rows are recorded, and the recording speed is reduced by the reciprocating recording. Moreover, 8 nozzles/
With layer ■ head! High-density recording of 6 dots/l1m1 was possible.

In the following explanation, a recording apparatus was described in which the recording paper is fixed (not shown) and sub-scanning the recording paper with the recording paper 1, but the recording paper 1 only performs main scanning in the reciprocating direction, and does not perform sub-scanning. It goes without saying that the present invention can be similarly applied to a recording apparatus in which the recording paper is fed in a direction perpendicular to the main scanning direction, and in that case, the recording paper 10 in FIG. What is necessary is to perform sub-scanning in the direction of arrow 12.

Furthermore, the application of the present invention is not limited to the ink ejection means, but may include a heater provided in the nozzle,
Equipped with a multi-nozzle head that ejects ink droplets using an inkjet for recording, such as one that ejects ink using air bubbles generated by heating, or one that ejects ink by distorting the nozzle using a piezoelectric element. Needless to say, the present invention can be similarly applied to any discharge means.

[Effects of the Invention] As explained below, according to the present invention, a multi-nozzle head in which a plurality of nozzle holes are arranged at intervals of P is used, and the head is arranged perpendicularly to the direction in which the nozzle holes are arranged. Since the reciprocating main scanning rotation is performed in the direction, the toe and toe positions are recorded with a difference of 1/2 of the nozzle hole spacing JP in the direction of the dot row between forward and backward sowing. Using a multi-nozzle head with relatively wide spacing between nozzle holes, it is possible to print twice as many dot rows as the number of nozzle holes by scanning back and forth, achieving both high image quality and high speed. That became a major concern.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of the configuration of a multi-nozzle head used in the present invention when viewed from the ejection surface side, and FIG. It is an explanatory diagram of operation. 1... Head, 2... Nozzle hole, 4-1 to 4-128... Dot row formed during forward scanning,
? -1 to 7-128... Dot row formed during backward scanning,
10... Recording paper.

Claims (1)

[Claims] In a recording method in which recording is performed by relatively scanningly moving a recording head having a plurality of nozzle holes for ejecting liquid and a recording member, the scanning includes a main scan and a sub-scan in a direction perpendicular to the main scan direction. scanning, and the amount of movement in the sub-scanning direction is an integral multiple of the amount of movement of 1/2 of the distance P between the nozzle holes in the direction perpendicular to the main scanning direction.