WO2021260812A1 - Droplet discharging module, droplet discharging unit, and method for manufacturing droplet discharging module - Google Patents

Abstract

Provided are a droplet discharging module capable of more stably discharging droplets at a high resolution, a droplet discharging unit, and a method for manufacturing the droplet discharging module. A droplet discharging module (11) is provided with a plurality of droplet discharging heads (111a, 111b) having a plurality of nozzles (N) that discharge droplets. The nozzles (N) of the plurality of droplet discharging heads (111a, 111b) are aligned at prescribed intervals (d) in a prescribed width direction (Y), and nozzles (N) adjacent in the width direction (Y) have mutually different droplet discharging heads (111a, 111b). The plurality of droplet discharging heads (111a, 111b) satisfy a prescribed standard pertaining to a relative angle with respect to the width direction (Y) of the droplet discharging direction between the plurality of nozzles (N) and each nozzle (N) adjacent to the plurality of nozzles (N).

Description

Manufacturing method of droplet ejection module, droplet ejection unit and droplet ejection module

The present invention relates to a method for manufacturing a droplet ejection module, a droplet ejection unit, and a droplet ejection module.

There is a droplet ejection device equipped with a droplet ejection head in which a plurality of nozzles for ejecting droplets of ink or the like are arranged. In response to the demand for higher accuracy related to the output content of the droplet ejection device, the arrangement interval of the nozzles in the droplet ejection head is gradually becoming narrower.

On the other hand, there is a technique of using a droplet ejection module in which the nozzle spacing is reduced as a whole by combining a plurality of droplet ejection heads and fixing the nozzles so as to be staggered in a predetermined width direction. Patent Document 1). This enables high-resolution droplet ejection without reducing the yield of the individual droplet ejection heads.

Japanese Unexamined Patent Publication No. 11-34360

However, there is a problem that the variation of a plurality of droplet ejection heads combined in the droplet ejection module may affect the image quality.

An object of the present invention is to provide a method for manufacturing a droplet ejection module, a droplet ejection unit, and a droplet ejection module capable of more stable and high-resolution droplet ejection.

In order to achieve the above object, the invention according to claim 1 is
A plurality of droplet ejection heads having a plurality of nozzles for ejecting droplets are provided.
The nozzles of the plurality of droplet ejection heads are arranged at predetermined intervals in a predetermined width direction.
The nozzles adjacent to each other in the width direction are the nozzles of the droplet ejection heads different from each other.
The plurality of droplet ejection heads satisfy a predetermined criterion relating to the relative angle of the droplet ejection direction between the plurality of nozzles and the nozzles adjacent to the plurality of nozzles in the width direction. It is a droplet ejection module.

The invention according to claim 2 is the droplet ejection module according to claim 1.
The predetermined reference is that the number of sets of the nozzles whose relative angle is equal to or larger than the reference angle is less than the predetermined upper limit.

The invention according to claim 3 is the droplet ejection module according to claim 2.
At least one of the nozzles of the group whose relative angle is equal to or larger than the reference angle is defined as a ejection prohibition nozzle.

The invention according to claim 4 is the droplet ejection module according to claim 2 or 3.
The reference angle is such that the distance in the width direction between the landing positions of the droplets ejected from each nozzle of the set and landed at a position of a predetermined reference distance from the opening surface of the nozzle is from the predetermined distance. It is an angle that is off by half.

The invention according to claim 5 is the droplet ejection module according to any one of claims 1 to 4.
The deviation of the distance between the landing positions of the droplets ejected by the nozzles at both ends in the width direction of the droplet ejection head is not more than half of the predetermined interval.

Further, the invention according to claim 6 is based on the invention.
A droplet ejection unit having a plurality of droplet ejection modules according to any one of claims 1 to 5.

Further, the invention according to claim 7 is based on the invention.
A droplet having a predetermined number of two or more droplet ejection heads having a plurality of droplet ejection heads, and the nozzles of different droplet ejection heads are adjacent to each other in a predetermined width direction and arranged at a predetermined interval as a whole. It is a manufacturing method of the discharge module.
A direction acquisition step of acquiring the droplet ejection directions of the plurality of nozzles in the plurality of droplet ejection heads,
For any combination of the predetermined number of the plurality of droplet ejection heads for which the droplet ejection direction has been acquired, the relative of the nozzles adjacent to each other in the width direction by the combination between the droplet ejection directions. Calculation step to calculate each angle,
A selection step of selecting the predetermined number of droplet ejection heads whose relative angles meet a predetermined criterion.
including.

The invention according to claim 8 is the method for manufacturing a droplet ejection module according to claim 7.
In the combination of the selected predetermined number of droplet ejection heads, the prohibition setting step of setting at least one of the adjacent nozzles whose relative angle is equal to or larger than the reference angle to the ejection prohibition is included.

According to the present invention, there is an effect that more stable and high-resolution droplet ejection is possible.

It is a perspective view of the droplet ejection unit. It is a bottom view of the droplet ejection unit. It is a figure explaining the arrangement of nozzles. It is a figure explaining the relative deviation of a discharge direction. It is a flowchart which shows the procedure of the combination setting process of a droplet ejection head. It is a flowchart which shows the other example of the combination setting process.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view of the droplet ejection unit 1 of the present embodiment. FIG. 2 is a bottom view of the droplet ejection unit 1.

The droplet ejection unit 1 includes a plurality of (here, eight) droplet ejection modules 11 and a fixing member 12 for fixing the droplet ejection modules 11 in a predetermined positional relationship.

The fixing member 12 has holes corresponding to the number of droplet ejection modules 11, and the droplet ejection modules 11 are fixed at positions where the bottom surface thereof is exposed from the holes. The fixing member 12 is fixed to a carriage or the like in a droplet ejection device such as an inkjet recording device, and the bottom surface of the droplet ejection module 11 and the landing target of the droplet ejected from the droplet ejection module 11 face each other. The eight droplet ejection modules 11 are arranged in a houndstooth pattern at positions different from each other in the Y direction, which is the longitudinal direction of the droplet ejection unit 1.

As shown in FIG. 2, each of the droplet ejection modules 11 includes two (plural) droplet ejection heads 111 arranged in the X direction perpendicular to the Y direction in the bottom surface. The droplet ejection head 111 has a large number (s) of nozzles N, and each nozzle N is open to the bottom surface.

FIG. 3 is a diagram illustrating an arrangement of nozzles.
In the droplet ejection module 11, in each nozzle row of the first droplet ejection head 111a and the second droplet ejection head 111b, a plurality of nozzles N are arranged in the Y direction at intervals of 4d. The nozzles N11 and N12 belonging to different nozzle rows of the first droplet ejection head 111a are located at intervals of 2d in the Y direction. The nozzles N21 and N22 belonging to different nozzle rows of the second droplet ejection head 111b are located at intervals of 2d in the Y direction. The first droplet ejection head 111a and the second droplet ejection head 111b are located at a distance d in the Y direction. As a result, the opening positions of the nozzles N of the two droplet ejection heads 111 are arranged alternately in the Y direction, and have an interval d (predetermined interval) in the width direction as a whole.

In the droplet ejection device, the droplet ejection unit 1 is, for example, a relative movement direction between the recording medium and the droplet ejection unit 1 at the time of droplet ejection (the transport direction of the recording medium and / or the scanning direction of the droplet ejection unit). Is installed so that is in the X direction. Liquid periodically from each nozzle arranged in the Y direction (that is, the direction perpendicular to the transport direction in the transport surface of the recording medium; the width direction of the recording medium) while moving the recording medium with respect to the droplet ejection unit 1. By enabling the droplets to be ejected, the droplet ejection unit 1 operates as a line head.

Due to such an arrangement of nozzles, each nozzle of each droplet ejection module 11 (other than the nozzles at both ends in the Y direction) has two nozzles adjacent to each other in the Y direction, and a set of two adjacent nozzles is formed. The nozzles belong to different droplet ejection heads 111. Here, for example, the nozzle N12 belonging to the first droplet ejection head 111a constitutes a set of nozzles p2 and p3 adjacent to the nozzles N21 and N22 belonging to the second droplet ejection head 111b, respectively. Similarly, the nozzle N21 belonging to the second droplet ejection head 111b constitutes a set of nozzles p1 and p2 adjacent to the nozzles N11 and N12 belonging to the first droplet ejection head 111a, respectively.

Ideally, the droplets ejected from each nozzle fly and land in the direction perpendicular to the bottom surface of the droplet ejection module 11 (droplet ejection head 111), but in reality, there are some deviations and variations. .. When the resolution of the droplet ejection module 11 is 1200 dpi, the interval d is about 21.2 μm, and when the distance from the bottom surface of the droplet ejection head 111 to the landing surface of the recording medium is 2 mm, the flight direction is the bottom surface. By deviating by 0.6 degrees from the direction perpendicular to the nozzle N, the landing position deviates by a distance d from just below the opening of the nozzle N. It is known that this deviation may be structurally biased in units of the droplet ejection head 111 due to manufacturing characteristics in addition to the variation of individual nozzles.

That is, even if the amount of displacement is within the permissible range for each droplet ejection head 111 as a single unit and the droplet ejection head 111 is accurately attached to the droplet ejection module 11, the first droplet ejection head 111a and the first droplet ejection head 111a and the first droplet ejection head 111a are attached. Depending on the combination of the deviation bias with the two-droplet ejection head 111b, the deviation relative to the Y-direction component in the flight direction of the droplet becomes so large that it cannot be ignored (that is, it may adversely affect the image quality). In some cases.

FIG. 4 is a diagram illustrating a relative deviation in the discharge direction. Here, the flight direction of the droplets ejected from the front surface (X direction) to the lower part of the figure (−Z direction) is shown. The ejection direction of the droplet from the first droplet ejection head 111a is indicated by a thin line, and the ejection direction of the droplet from the second droplet ejection head 111b is indicated by a thick line.

In this figure, for example, the ejection direction from the first droplet ejection head 111a is slightly biased to the right (−Y direction) in the plane of the figure, and the ejection direction from the second droplet ejection head 111b is the surface of the figure. It is slightly biased to the left (+ Y direction) inside.

The ejection direction e1 from one nozzle N of the first droplet ejection head 111a and the ejection directions e21 and e22 from the nozzle N adjacent to the nozzle of the second droplet ejection head 111b are mutually in the Y direction. There is a shift in the opposite direction. The angles formed between these droplet ejection directions (relative angles r11 and r12 in the width direction) are the sum of the angles of deviation in the ejection direction from each nozzle and greatly deviate from 0 degrees.

In the droplet ejection module 11 in which the first droplet ejection head 111a and the second droplet ejection head 111b are combined, a large variation occurs at the landing position as compared with the variation in the individual droplet ejection heads 111. This adversely affects the image quality. In the droplet ejection module 11 of the present embodiment, the first droplet ejection head 111a and the second droplet ejection head 111b are arranged so that the variation (relative angle) in the ejection direction is within a predetermined reference angle range (predetermined). Selected and combined (to meet the criteria of).

The reference angle may be appropriately determined according to the required image quality of the droplet ejection module 11, and for example, even if the relative displacement amount of the landing position is determined so as to be able to be compared with the nozzle spacing d as described above. good. The amount of misalignment at the time of landing depends on the distance between the nozzle opening surface and the droplet landing surface of the recording medium, but in the droplet ejection device, the thickness of the recording medium often changes significantly. Therefore, the amount of misalignment is calculated based on the reference distance (reference distance). For example, the amount of misalignment may be calculated with the maximum settable distance as the reference distance, or the distance corresponding to the thickness of the standard recording medium may be the reference distance. Assuming that the distance G [mm], the resolution of the droplet ejection module 11 is D [dpi], the reference angle is R [deg], and half of the nozzle spacing d is the maximum misalignment amount, G × tan in the range where R is minute. (R) = 0.5 × 25.4 / D, which is estimated to be R = 727 / (DG). In a normal ink droplet, the density unevenness at this degree of deviation is negligible in many cases, but the degree of unevenness or the like depends on the relationship between the landing range of the landed droplet and the distance d. Therefore, for example, when the landing range of the droplet is narrow, the reference angle may be set smaller.

Here, it is not necessary for all the nozzle N sets to be within the range of the reference angle. In this case, for example, when the number of sets whose relative angle is equal to or larger than the reference angle is less than the predetermined upper limit number, the reference number is concerned. For each set of, one of the nozzles may be set as an initial defective nozzle and discharge prohibition may be set. The list of nozzles (discharge prohibition nozzles) set to discharge prohibition may be stored in a storage means such as a ROM included in the droplet discharge module 11 or the droplet discharge unit 1. In the droplet ejection device, based on this list of ejection prohibited nozzles, the droplet ejection from the ejection prohibited nozzle is prohibited, and the drive control is performed so that complementary ejection is performed by the nozzles N on both sides instead.

FIG. 5 is a flowchart showing the procedure of the combination setting process of the droplet ejection head 111 of the present embodiment. This combination setting process is executed, for example, by the CPU of a computer for manufacturing control as a part of the manufacturing process of the droplet ejection module 11 (the manufacturing method of the droplet ejection module 11).

This CPU acquires information (measurement data) of the droplet ejection direction by each nozzle of the plurality of droplet ejection heads 111 that can be used for the droplet ejection head (step S101; direction acquisition step). If the measurement data is acquired directly from the manufactured inspection device of the droplet ejection head 111 or the like in association with the identification information (serial number, etc.) of each droplet ejection head 111, or via a data storage device. good.

The CPU selects two droplet ejection heads 111 in a combination that has not yet been selected (step S102). The CPU specifies all pairs of adjacent nozzles according to the arrangement order of the nozzles in the Y direction (width direction) when the two selected droplet ejection heads 111 are attached to the droplet ejection module. The CPU calculates the relative angle according to the difference in the discharge direction of each specified set (step S103; calculation step).

The CPU counts the number of non-standard pairs, with the pairs whose calculated relative angle (absolute value) is equal to or greater than the reference angle as non-standard pairs (step S104). If a nozzle with an abnormality in the droplet ejection itself is included due to an initial failure of the nozzle, etc., the set including this nozzle is regarded as a nonstandard set regardless of the droplet ejection direction by the nozzle. May be good. The CPU determines whether or not all the sets of the plurality of target droplet ejection heads have been selected (step S105). If it is determined that there is a set that has not been selected (“NO” in step S105), the CPU processing returns to step S102.

When it is determined that all the sets are selected (“YES” in step S105), the CPU extracts the sets of the droplet ejection heads whose non-standard number of sets is less than the reference number (upper limit number) (step). S106). The reference number may be arbitrarily determined according to the required level of the product, and may be, for example, 10%, more preferably 1% of the total number of nozzles. In addition to the number of non-standard pairs, conditions such as adjacent pairs that are not non-standard in succession may be added. The CPU determines a combination in which the maximum number of droplet ejection heads can be combined (step S107; selection step). The CPU sets the nozzles of the nonstandard set as the initial defective nozzles in each combination of the determined droplet ejection heads (step S108; prohibition setting step). The initial defective nozzle setting may be one of a non-standard set of nozzles. If it is clear that the cause is one of them, the one may be selected, and if it is not a clear abnormality, the deviation from the droplet ejection direction of all the nozzles is large. It may be one or the like. Then, the CPU ends the combination setting process.

Even if the combination is defined as a set that meets the standard at the setting stage of the combination, it may be distorted due to heat or the like when it is actually fixed to the droplet ejection module 11. In this case, the length of the droplet ejection module 11 in the width direction, for example, the reference of the droplet ejected from the nozzles at both ends in the width direction of the droplet ejection module 11 without re-measuring the ejection direction of each nozzle. The effect of distortion can be determined by the distance between the landing positions (distance between both ends) and the like. Here, when the measured distance between both ends deviates from the original distance (distance d × (number of nozzles-1)) by half or more of the distance d, it may be excluded as being distorted.

FIG. 6 is a flowchart showing another example of the combination setting process.
In the combination setting process of this example, step S107 of the above combination setting process is changed to steps S117 and S118, and the other processes are the same. The same processing contents are designated by the same reference numerals and detailed description thereof will be omitted.

After the process of step S106, the CPU quantitatively evaluates the variation in the ejection direction for each of the droplet ejection heads of the extracted combinations (step S117). The CPU may calculate various statistical parameters such as, for example, the average value of the absolute values of the relative angles. The CPU determines the combination of the droplet ejection heads in ascending order of the degree of variation obtained in the quantitative evaluation (step S118). When the CPU determines the combination having the minimum degree of variation, the CPU erases the other combinations including the droplet ejection head of the combination. Then, the determination of the combination having the smallest degree of variation among the remaining combinations is repeated until there are no remaining combinations. Then, the processing of the CPU shifts to step S108.

As described above, the droplet ejection module 11 of the present embodiment includes a plurality of droplet ejection heads 111 having a plurality of nozzles N for ejecting droplets. The nozzles N of the plurality of droplet ejection heads 111 are arranged at a predetermined interval d in a predetermined width direction (Y direction), and the nozzles N adjacent to each other in the width direction are nozzles N having different droplet ejection heads 111. Is. The plurality of droplet ejection heads 111 satisfy a predetermined criterion relating to a relative angle in the width direction of the droplet ejection direction between the plurality of nozzles N and the nozzles N adjacent to each of the plurality of nozzles N. ..
As described above, each droplet ejection head is determined by determining the droplet ejection head 111 in which the droplet ejection module 11 is combined in consideration of the relative difference in the droplet ejection direction of each droplet ejection head 111. In 111, it is possible to obtain a droplet ejection module 11 capable of stably ejecting a droplet with high resolution by suppressing a large variation in the ejection direction and the landing position due to a relative deviation even within the range of the standard. can.

In addition, the predetermined reference is that the number of sets of nozzles N whose relative angle is equal to or greater than the reference angle is less than the predetermined upper limit. It is difficult in manufacturing that the set of all nozzles N does not completely disperse, and the yield decreases. It can be done stably.

Further, at least one of the nozzles N of the set whose relative angle is equal to or larger than the reference angle is defined as a discharge prohibition nozzle. As described above, when the relative angle becomes large due to the set of nozzles N, one nozzle N is not discharged as a discharge prohibited nozzle, but is complemented by nozzles on both sides in the same manner as a normal discharge prohibited nozzle. , It may be possible to avoid the influence of the deviation in the discharge direction. By making such a setting, more stable and highly accurate droplet ejection can be performed from the droplet ejection module 11.

Further, the reference angle is the droplets ejected from each nozzle N of each set and landed at a predetermined reference distance from the opening surface of the nozzle N, for example, the maximum distance determined according to the type of recording medium. The distance in the width direction between the landing positions is an angle that deviates from the nozzle N spacing d by half (d / 2). If the deviation is about half of each pixel, in many cases, leakage from the landing range or unevenness of the landing density will not be negligible depending on the landing size of the droplet, so this is an example. Can be set based on such a value.

Further, the deviation of the distance between the landing positions of the droplets ejected by the nozzles N at both ends in the width direction of the droplet ejection head 111 is less than half of the interval d. Even if the combination of the droplet ejection heads 111 is made more appropriate, it cannot be said that distortion may occur at the time of combination. In this case, by measuring the distance between the droplet landing positions by the nozzle N, which is the farthest distance in the width direction, the cumulative value of the entire strain can be obtained, so this distance is within the reference range (half of the interval d). By shipping the droplet ejection module 11 of the above, it is possible to supply the droplet ejection module 11 capable of more stable and highly accurate droplet ejection.

Further, the droplet ejection unit 1 of the present embodiment has a plurality of the above-mentioned droplet ejection modules 11. In the droplet ejection unit 1 having a plurality of droplet ejection modules 11 such as a line head, the droplets can be landed on the medium more accurately by stably aligning the ejection directions in this way. In particular, in the droplet ejection unit 1 that does not change the position in the width direction like the line head, the deviation of the landing position in the width direction directly affects the quality of the output content. , Stable output accuracy can be obtained.

Further, the method for manufacturing the droplet ejection module 11 of the present embodiment includes a direction acquisition step for acquiring the droplet ejection directions of the plurality of nozzles N in the plurality of droplet ejection heads 111, and a plurality of acquisition of the droplet ejection directions. For any (basically all) combinations that select a predetermined number (here, two) from the droplet ejection head 111, the droplet ejection direction of the nozzle N that is adjacent in the width direction (Y direction) depending on the combination. It includes a calculation step of calculating each relative angle between the two, and a selection step of selecting a predetermined number of droplet ejection heads whose relative angle meets a predetermined criterion.
In this way, the relative angles are calculated for all available nozzles N of any (especially all) droplet ejection heads 111 that can be combined, and the degree of compatibility of the combinations is compared, so that the liquid is liquid with high accuracy on average. It is possible to obtain a droplet ejection module 11 having the same droplet ejection directions. In addition, since the degree of conformity is checked in many combinations, even if the droplet ejection head 111 has a slight habit in the droplet ejection direction, it is easy to find any other droplet ejection head 111 that can be combined, and the yield can be improved. Hard to lower.

Further, in this manufacturing method, in the combination of the selected predetermined number (two) of the droplet ejection heads 111, at least one of the adjacent nozzles N having a relative angle equal to or larger than the reference angle is prohibited from being ejected. It may include a setting step. It is difficult in manufacturing that the set of all nozzles N does not completely disperse, and the yield will decrease. By setting the ejection prohibition, the ejection complementation by the nozzles N on both sides conventionally used can be applied, and the influence on the output quality can be minimized.

The present invention is not limited to the above embodiment, and various modifications can be made.
For example, in determining the combination of the droplet ejection heads, it has been described that a plurality of droplet ejection heads are evaluated evenly, but the present invention is not limited to this. Priority may be given according to the number of initial defective nozzles and the like. Further, when the droplet ejection head for which the combination setting has not been made is included again in the next combination setting, the droplet ejection head may be preferentially set in combination, or conversely, the combination may be performed by lowering the priority. You may set it.

Further, in the above embodiment, the case where two droplet ejection heads are combined to form a droplet ejection module has been described, but three or more droplet ejection heads may be combined. For example, when three are combined, two nozzles adjacent to a nozzle belonging to any first droplet ejection head belong to one of the other second droplet ejection heads. The nozzles may be arranged so that the other belongs to a further different third droplet ejection head. Also in this case, the combination of the three droplet ejection heads is determined so that the reference of the relative angle is satisfied for all the combinations of adjacent nozzles.

Further, in the above embodiment, the relative angle between some nozzles may be equal to or larger than the reference angle. In this case, one of the nozzles having the reference angle or more is the ejection prohibited nozzle, except for the initial defective nozzle. , The reference angle and the combination reference may be set so that the relative angle between all the nozzles is less than the reference angle.

Further, in the above embodiment, any one of the nozzles N in the set whose relative angle is equal to or larger than the reference angle is set as ejection prohibition, but if the relative angle is about half of the interval d, ejection prohibition is set and both sides are adjacent. Since there is a case where the accuracy is not lowered by discharging from both nozzles N as it is rather than performing complementary discharge from the nozzle N of Nozzle N, it is not necessary to uniformly set the discharge prohibition. Discharge prohibition may be set only when the predetermined upper limit angle or more, which is larger than the reference angle, is set. May be.

Further, in the above embodiment, the nozzles N are arranged in a houndstooth pattern on each droplet ejection head 111, but the arrangement pattern of the nozzles is not limited to this. It suffices to line up at predetermined intervals in the width direction.

Further, in the above embodiment, the droplet ejection head for ejecting ink by the inkjet recording device has been described, but the present invention is not limited to this. A liquid other than ink may be ejected. For example, droplets of various materials for forming a thin film, a three-dimensional structure, a wiring circuit, or the like may be ejected.
In addition, the specific configuration, the content and procedure of the processing operation shown in the above embodiment can be appropriately changed without departing from the spirit of the present invention. The scope of the present invention includes the scope of the invention described in the claims and the equivalent scope thereof.

The present invention can be used in a method for manufacturing a droplet ejection module, a droplet ejection unit, and a droplet ejection module.

1 Droplet ejection unit 11 Droplet ejection module 12 Fixing member 111 Droplet ejection head N, N11, N12, N21, N22 Nozzle

Claims (8)

1. A plurality of droplet ejection heads having a plurality of nozzles for ejecting droplets are provided.
   The nozzles of the plurality of droplet ejection heads are arranged at predetermined intervals in a predetermined width direction.
   The nozzles adjacent to each other in the width direction are the nozzles of the droplet ejection heads different from each other.
   The plurality of droplet ejection heads satisfy a predetermined criterion relating to the relative angle of the droplet ejection direction between the plurality of nozzles and the nozzles adjacent to the plurality of nozzles in the width direction. Droplet ejection module.
2. The droplet ejection module according to claim 1, wherein the predetermined reference is a set of nozzles whose relative angle is equal to or larger than the reference angle and is less than a predetermined upper limit number.
3. The droplet ejection module according to claim 2, wherein at least one of the nozzles of the group whose relative angle is equal to or larger than the reference angle is defined as a ejection prohibited nozzle.
4. The reference angle is such that the distance in the width direction between the landing positions of the droplets ejected from each nozzle of the set and landed at a position of a predetermined reference distance from the opening surface of the nozzle is from the predetermined distance. The droplet ejection module according to claim 2 or 3, which has a half-shifted angle.
5. One of claims 1 to 4, wherein the deviation of the distance between the landing positions of the droplets ejected by the nozzles at both ends in the width direction of the droplet ejection head is not more than half of the predetermined interval. Droplet ejection module according to the section.
6. A droplet ejection unit having a plurality of droplet ejection modules according to any one of claims 1 to 5.
7. A droplet having a predetermined number of two or more droplet ejection heads having a plurality of droplet ejection heads, and the nozzles of different droplet ejection heads are adjacent to each other in a predetermined width direction and arranged at a predetermined interval as a whole. It is a manufacturing method of the discharge module.
   A direction acquisition step of acquiring the droplet ejection directions of the plurality of nozzles in the plurality of droplet ejection heads,
   For any combination of the predetermined number of the plurality of droplet ejection heads for which the droplet ejection direction has been acquired, the relative of the nozzles adjacent to each other in the width direction by the combination between the droplet ejection directions. Calculation step to calculate each angle,
   A selection step of selecting the predetermined number of droplet ejection heads whose relative angles meet a predetermined criterion.
   A method of manufacturing a droplet ejection module, including.
8. In the combination of the selected predetermined number of droplet ejection heads, the prohibition setting step of setting at least one of the adjacent nozzles whose relative angle is equal to or larger than the reference angle to the ejection prohibition is included.
   The method for manufacturing a droplet ejection module according to claim 7.

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