JP2003001804A - Ink jet printer, nozzle number calculation method, ink jet printing method, and print medium - Google Patents

Abstract

(57) [Problem] To print an image of a plurality of continuous lines, such as a barcode, with a desired line width in consideration of ink bleeding when printing on a print medium by an inkjet method. SOLUTION: An ink jet head ejects ink from X consecutive nozzles using a print width A and a dot pitch P when printing is performed by one nozzle of an ink jet head using a predetermined print medium and ink. The print line width B when printing a black bar of a bar code is represented by “B = A
+ P * (X-1) "(steps S4 and S
6, S8). Then, assuming that the specified line width of the black bar is C, the number of nozzles X at which “| CB−” becomes minimum is calculated. The number Y of nozzles when printing the space between black bars without discharging ink from Y nozzles that are continuous by the inkjet head is also determined.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet printer, a nozzle number calculation method, an inkjet printing method, and a print medium.

[0002]

Bar codes are used in many applications as information sources. For example, it is used for pricing and inventory management in the retail industry, and for factory management processes and inventory management systems in the manufacturing industry. As described above, since the barcode has information in itself, it is necessary to print a black bar defined by the JIS standard with a width according to the standard because the barcode itself has information. Therefore, for printing the barcode, a thermal recording method using a heat-sensitive recording paper capable of printing with high printing dimensional accuracy, a printing method using a plate by a printing plate, and the like are used.

However, in the printing of barcodes of a wide variety of products in small lots, the printing method using a printing plate has a problem that the printing plate must be frequently replaced, and the thermal printing method directly contacts the printing medium. Since this printing method is applied, there is a problem that it cannot be applied when the surface is soft and is deformed by an applied force.

Therefore, recently, it has been expected to apply an ink jet recording system suitable for a large variety of small lots.

However, in the ink jet recording system, the dot shape in which ink droplets are formed on the print medium is
Instability due to ink bleeding makes it difficult to print with a predetermined dimensional accuracy.

A technique for covering the deterioration of the dimensional accuracy of printing due to such ink bleeding and ensuring a predetermined printing accuracy is disclosed in, for example, Japanese Patent No. 2742156. The publication discloses a technique in which the width of the black bar satisfies the standard by correcting the number of pixel columns forming the black bar.

[0007]

However, the ink bleeding amount varies depending on the printing medium and the type of ink. On the other hand, in the technology disclosed in Japanese Patent No. 2742156 or the like, there is no means for responding to fluctuations in the amount of bleeding due to the actual ink that occurs depending on the type of print medium and ink, and the There is a problem in that the printing accuracy of the barcode cannot be maintained in response to variations in types.

When the printing conditions such as the printing medium, the ink and the resolution are different, the printing is performed each time, and if the required line width is not measured, the printing accuracy is secured by the ink bleeding. It is not possible to do so, and there is a problem that it is complicated and time-consuming.

Further, there is a problem that the required printing accuracy cannot be satisfied not only for the width of the black bar but also for the width of the space (white bar).

An object of the present invention is to make it possible to print an image of a plurality of continuously arranged lines such as a bar code with a desired line width in consideration of ink bleeding when printing on a print medium by an ink jet system. In addition, even if the print medium and ink are different, it is possible to set the number of nozzles that eject or not eject the ink of the inkjet head necessary for forming the line and the space between the lines, so that an image of a plurality of lines can be obtained with desired accuracy. It is possible to print.

An object of the present invention is to set the number of nozzles for ejecting ink of an ink jet head necessary for forming a line and print an image of a plurality of lines with desired accuracy.

An object of the present invention is to set the number of nozzles which do not eject ink of an ink jet head necessary for forming a space between lines and print an image of a plurality of lines with desired accuracy.

The object of the present invention is to provide a different resolution,
This is to set the number of nozzles that eject or not eject ink of the inkjet head necessary for forming a line and a space between lines to print an image of a plurality of lines with desired accuracy.

An object of the present invention is to enable printing with a pitch narrower than the nozzle pitch of an ink jet head, and to print an image with higher resolution.

[0015]

According to a first aspect of the present invention, there is provided an ink jet printer for printing on a print medium by an ink jet head having a plurality of nozzles for ejecting ink arranged in a line at a predetermined pitch. The print width data receiving means for receiving the data of the print width A when printing is performed by one of the nozzles of the inkjet head using the print medium and the ink, and the dot pitch when printed by the inkjet head is P. At this time, when the dot pitch P and the print width A are used (where A> P), ink is ejected from the X continuous nozzles by the inkjet head to print a plurality of lines that are continuously arranged. A print line width calculation means for calculating the print line width B by calculating the formula (1) B = A + P * (X-1) (1). And assuming that the prescribed line width of the line is C, "| C-B
The first nozzle number calculation means for calculating the number X of nozzles when || becomes the minimum, and the width of the space between the lines formed by not ejecting ink from the continuous Y nozzles is F. When F = P * (Y + 1) -A (2), the space width calculation means for calculating the space width F by performing the calculation of the formula (2), and the specified width of the space is C ′. Second nozzle number calculation means for calculating the nozzle number Y when "| C'-F |" is minimized, and the nozzle number X and Y obtained by the first and second nozzle number calculation means.
An ink jet printer comprising: print control data for printing the plurality of lines using the print control data, and a printing unit that drives the ink jet head according to the print control data to print.

Therefore, in consideration of ink bleeding when printing on a print medium by the ink jet method, it is possible to print an image of a plurality of continuously arranged lines such as a bar code with a desired line width, and the print medium. Even if the inks are different, it is possible to set the number of nozzles that eject or not eject the ink of the inkjet head necessary for forming the lines and the spaces between the lines, and it is possible to print an image of a plurality of lines with desired accuracy. .

According to a second aspect of the present invention, in the ink jet printer according to the first aspect, when the first nozzle number calculation means is N, which is a continuous arbitrary integer,
Substituting N-1, N, and N + 1 into the number of nozzles X in the equation (1), N when "B (N-1)> B (N) <B (N + 1)" is "| C- It is characterized in that it is calculated as the number of nozzles X when B | ”becomes the minimum.

Therefore, it is possible to set the number of nozzles for ejecting the ink of the ink jet head necessary for forming the line and print an image of a plurality of lines with desired accuracy.

According to a third aspect of the present invention, in the ink jet printer according to the first or second aspect, the second aspect of the invention is provided.
The number-of-nozzles calculating means substitutes N-1, N, N + 1 into the number of nozzles Y in the equation (2), where N is a continuous arbitrary integer, and then "F (N-1)>F". (N) <F (N +
1) ”is calculated as N, which is the number of nozzles Y when“ | C′−F | ”is minimum.

Therefore, it is possible to print the image of a plurality of lines with a desired accuracy by setting the number of nozzles that do not eject the ink of the ink jet head necessary for forming the space between the lines.

According to a fourth aspect of the present invention, in the ink jet printer according to any one of the first to third aspects, resolution data receiving means for receiving data of resolution used for printing, and the dot based on this resolution. And a dot pitch calculating means for obtaining the pitch P.

Therefore, even if the resolutions are different, it is possible to set the number of nozzles that eject or do not eject the ink of the ink jet head necessary for forming the lines and the spaces between the lines, and print an image of a plurality of lines with desired accuracy. can do.

According to a fifth aspect of the present invention, in the ink jet printer according to the fourth aspect, a head drive mechanism that drives the ink jet head to change the arrangement direction of the nozzles with respect to the print medium, and the dot pitch calculation. Comparing means for comparing the dot pitch P obtained by the means with the nozzle pitch T of the inkjet head; and controlling means for controlling the head drive mechanism according to the result of the comparison to perform the predetermined amount of the change. It is characterized by having.

Therefore, it is possible to print at a pitch narrower than the nozzle pitch of the ink jet head, and it is possible to print a high resolution image.

According to a sixth aspect of the present invention, a plurality of lines are continuously arranged in an ink jet system for printing on a print medium by an ink jet head in which a plurality of nozzles for ejecting ink are arranged in a line at a predetermined pitch. When printing, the number of nozzles that determines the number of consecutive nozzles that eject ink from the inkjet head to print the line and the number of consecutive nozzles that form a space between the lines by not ejecting ink from the nozzles In the calculation method, when the print width when printing with one or a plurality of the nozzles of the inkjet head using a predetermined print medium and ink is A and the dot pitch when printing with the inkjet head is P, ,
Using this dot pitch P and print width A (where A>
P) Print line width B when printing the line when the number of nozzles that eject ink when printing the line is X
B = A + P * (X-1) (1) The print line width calculation step is performed by calculating the formula (1), and when the prescribed line width of the line is C, "| C- B
The first nozzle number calculation step of calculating the number X of nozzles when | ”is the minimum, and the width of the space is F when the number of nozzles that do not eject ink forming the space is Y.
Then, the space width calculation step of calculating the space width F by performing the calculation of the formula (2) F = P * (Y + 1) -A (2), and the specified width of the space is defined as C ′. And a second nozzle number calculating step for calculating the nozzle number Y when "| C'-F |" becomes the minimum, the nozzle number calculating method.

Therefore, in consideration of ink bleeding when printing on a print medium by the ink jet method, it is possible to print a plurality of continuously arranged images such as a bar code with a desired line width, and the print medium. Even if the inks are different, it is possible to set the number of nozzles that eject or not eject the ink of the inkjet head necessary for forming the lines and the spaces between the lines, and it is possible to print an image of a plurality of lines with desired accuracy. .

According to a seventh aspect of the present invention, in the nozzle number calculating method according to the sixth aspect, the first nozzle number calculating step is N-, where N is a continuous arbitrary integer.
Substituting 1, N, N + 1 into the number of nozzles X in the equation (1), N when "B (N-1)> B (N) <B (N + 1)" is "| C-B |" It is characterized in that it is calculated as the number X of nozzles when "" is the minimum.

Therefore, it is possible to set the number of nozzles for ejecting the ink of the ink jet head necessary for forming a line and print an image of a plurality of lines with desired accuracy.

According to an eighth aspect of the present invention, in the method of calculating the number of nozzles according to the sixth or seventh aspect, the second nozzle number calculating step is N-, where N is an arbitrary continuous integer. Substituting 1, N, N + 1 into the number of nozzles Y in the equation (2), "F (N-1)> F (N) <F (N + 1)"
Is calculated as the number of nozzles Y when "| C'-F |" is minimum.

Therefore, it is possible to print the image of a plurality of lines with a desired accuracy by setting the number of nozzles which do not eject the ink of the ink jet head necessary for forming the space between the lines.

According to a ninth aspect of the present invention, there is provided an ink jet printing method for performing printing on a print medium by an ink jet head in which a plurality of nozzles for ejecting ink are arranged in a line at a predetermined pitch. Printing control data for printing the plurality of lines is created using the nozzle numbers X and Y obtained by the nozzle number calculation method described in any one of the above, and the inkjet head is driven by this printing control data to perform printing. An inkjet printing method comprising a printing step.

Therefore, in consideration of ink bleeding when printing on a print medium by the ink jet method, it is possible to print a plurality of continuously arranged images such as a bar code with a desired line width, and the print medium. Even if the inks are different, it is possible to set the number of nozzles that eject or not eject the ink of the inkjet head necessary for forming the lines and the spaces between the lines, and it is possible to print an image of a plurality of lines with desired accuracy. .

According to a tenth aspect of the present invention, in the ink jet printing method according to the ninth aspect, the printing step prints a bar code as the plurality of lines.

Therefore, in consideration of ink bleeding when printing on a print medium by the ink jet system, a bar code image can be printed with a desired line width, and even if the print medium and ink are different, the bar code can be printed. It is possible to set the number of nozzles that eject or do not eject the ink of the inkjet head necessary for forming the black bar of the code and the space between the black bars, and it is possible to print the image of the bar code with desired accuracy.

According to an eleventh aspect of the present invention, in a print medium in which a bar code composed of a plurality of black bars continuously arranged is printed by an ink jet system, the dot pitch for printing the bar code is P, and the bar is When the printing width when printing with one or a plurality of the nozzles of the inkjet head used for printing the code is A, the number of consecutive nozzles of the inkjet head that ejects ink when the black bar is printed is calculated. When it is assumed that there are X, the print width A and the dot pitch P are used (where A>
P) When the print line width B of the black bar is expressed by the equation (1), B = A + P * (X-1) (1), the number of dots of the black bar is the specified line width of the black bar. Where C is "| CB
Is equal to the number of nozzles X when | ”is the minimum,
Assuming that the number of continuous nozzles of the inkjet head that does not eject ink when forming this space is Y, the width F of the space between the black bars is F = P * (Y + 1) -A. When expressed by the equation (2), the number of dots forming the space is the number of nozzles when “| C′−F |” is the minimum when the prescribed width of the space is C ′. Y
It is a print medium characterized by being equal to.

Therefore, in consideration of ink bleeding when printing on a print medium by the ink jet method, it is possible to provide a bar code printed with a desired line width, and even if the print medium and ink are different, the bar code can be provided. It is possible to provide a bar code printed with desired accuracy by setting the number of nozzles that eject or do not eject ink of an inkjet head necessary for forming a black bar of a code and a space between the black bars.

According to a twelfth aspect of the present invention, in the print medium according to the eleventh aspect, the number X of nozzles when "| C-B |" is the minimum is N, which is an arbitrary continuous integer. At this time, N-1, N, N + 1 are substituted for the number of nozzles X in the equation (1), and "B (N-1)> B (N) <B (N +
1) ”, which is the same as N.

Therefore, it is possible to provide the bar code printed with desired accuracy by setting the number of nozzles for ejecting the ink of the ink jet head necessary for forming the black bar.

According to a thirteenth aspect of the present invention, in the print medium according to the eleventh or twelfth aspect, "| C'-F |"
The number of nozzles Y at which is minimized is expressed by “F (N) by substituting N−1, N, N + 1 into the number of nozzles Y in the equation (2), where N is a continuous arbitrary integer. -1)> F
It is characterized in that N when (N) <F (N + 1) ”is calculated as.

Therefore, it is possible to provide a bar code printed with desired accuracy by setting the number of nozzles that do not eject ink of the ink jet head necessary for forming a space between black bars.

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a schematic structure of an ink jet printer 1 according to this embodiment. As shown in FIG. 1, the inkjet printer 1 includes a printer controller 2 that is a control device including a microcomputer that performs various calculations and centrally controls the entire inkjet printer 1.

The printer controller 2 is connected to the ink jet printer 1 through a predetermined interface.
A host computer 3 such as a PC for driving the printer is connected to a bar code print parameter input unit 4 that receives the input of parameter data.

The printer controller 2 includes a mechanism control circuit 8 for controlling various actuators (not shown) of the ink jet printer 1, and an ink jet head 5.
A head drive circuit 7 for driving the print head and a print dot pattern generation circuit 6 for generating a print dot pattern for printing with the inkjet head 5 are connected.

The bar code print parameter input unit 4 is an input device for accepting input of parameter data such as bar code type (ITF, JAN, etc.), its magnification, resolution and the like from the user. This bar code print parameter input section 4
May be composed of, for example, a keyboard for the user to input the parameter data, or a dip for selecting a desired one from the parameter data registered in advance in the ROM or the like of the printer controller 3 (described later). You may comprise with a switch.

When the bar code print parameter input unit 4 inputs a predetermined parameter, the printer controller 3
The number of nozzles of the black bar and the white bar to be printed at the time of printing the bar code is determined by performing calculation according to a predetermined program stored in 1. Next, when a barcode code to be printed is input from the host computer 3, the print dot pattern generation circuit 6 generates a dot pattern to be printed. The data generated by the print dot pattern generation circuit 6 is used for the head drive circuit 5
To the ink jet head 5 by a predetermined control.
The print control corresponding to the input barcode data is printed and recorded on the print medium by the mechanism control circuit 8 for controlling the conveyance of the print medium such as paper by a mechanism (not shown).

FIG. 2 is a perspective view of the ink jet head 5 portion. As shown in FIG. 2, a print medium a such as paper
Are conveyed in the direction of arrow 11 by a mechanism (not shown) controlled by the mechanism control circuit 8. Inkjet head 5
Ejects ink droplets onto the conveyed print medium a.
A drive circuit board 12 including a head drive circuit 7 for driving the ink jet head 5 and the like is attached to a board 13.

FIG. 3 is an enlarged plan view (a) of an orifice surface 22 in which a plurality of nozzles 21 for ejecting the ink of the ink jet head 5 are formed in parallel in a line at a predetermined pitch, and this orifice surface 22. It is an enlarged plan view (b) of the dots 23 ejected from and printed. T is the nozzle pitch and P is the dot pitch (T = P).

FIG. 4 is a schematic view illustrating a case where a specific bar code is printed on the print medium a. (A) is an enlarged plan view of the orifice surface 22, and (b) is an enlarged plan view of a barcode formed by ejecting ink from the orifice surface 22. This bar code is shown corresponding to each nozzle 21 on the orifice surface 22. In FIG. 4, reference numeral 31 indicates a black bar of the barcode, and reference numeral 32 indicates a white bar of the barcode.

FIG. 5 is an enlarged plan view of the bar code.
In FIG. 5, the black bar 31a has “X1 = 3” for the ink discharge nozzles 21 and the black bar 31b has “X2 = 9” for
The case where each is printed is shown. Shaded parts 33a, 33b
Indicates a situation in which the ink has spread to the print medium a and the print width has spread.

A white bar (space) 32 indicates a print area in which the nozzles that do not eject ink are formed by "Y1 = 6". As shown in FIG. 5, contrary to the case where the black bar 31 is formed, the printing width for printing with a predetermined number of nozzles due to ink bleeding becomes narrow due to this ink bleeding.

In this way, due to the ink bleeding, the black bar 3
The print width of 1 is wider than the width corresponding to the number of the ink discharge nozzles 21 used for discharging ink, or the space 3
Ink ejection nozzle 2 whose width of 2 is not used for ejecting ink
Since the width becomes smaller than the width corresponding to the number of 1 in order to realize a desired print width in the printing of the bar code, printing is performed when the inkjet printer 1 actually prints on the print medium a as follows. The width was measured and the variation of the print width was verified. The result is shown in FIG.

The ink jet head 5 used here is
Nozzle pitch density is 150dpi, 180dpi, 30
The ones of 0 dpi and 360 dpi were used. Also,
A commercially available PPC recording paper is used as the print medium a, and the ink is an oil-based pigment ink in which a pigment is dispersed in a petroleum solvent. When the ink temperature is 25 ° C., the viscosity is about 10 m.
A material having a Pas and a surface tension of about 30 mN / m was used.

FIG. 6 shows the numerical values of the printing results when these are used. The results of FIG. 6 are 150 dpi and 180 d.
In each case of pi, 300 dpi and 360 dpi (showing the nozzle pitch T in that case), the number of nozzles ejecting ink is changed, and the print line width at each nozzle number is measured using an optical microscope. is there.

Then, when the increase in the print line width due to the increase in the number of nozzles for ejecting ink is obtained, the average value for each resolution in the ink jet head 5 is almost the same as the dot pitch P, and at each nozzle number. It was found that the printed line width is represented by the following formula based on the measurement result of FIG.

B = A + P * (X-1) (1) In the formula (1), X is the number of nozzles, B is the print line width when printing with the number of nozzles X, and A is when printing with one nozzle. Is a print line width, P is a dot pitch P (nozzle pitch T).

In this way, by measuring the line width when printing with one nozzle for each type of ink and print medium a used for printing a predetermined bar code, the ink and print medium a are used. When the number of nozzles is X, the print line width can be obtained.

Next, a means for setting the width of the space 32 between the black bars 31 will be described. Here, from the equation (1), since the print line width A and the dot pitch P are constants, it is the number of nozzles X that affects the increase of the print line width B.
And the amount of bleeding of the ink ejected from the nozzles 21 located at both ends of the black bar 31. That is, even if the print line width B is increased by increasing the number of nozzles X, ink bleeding is caused by the nozzles 2 located at both ends of the X nozzles 21.
It only depends on the variation of the print width by 1.

Of course, the fluctuation of the bleeding amount also changes depending on the print medium a and the type of ink, and is also affected by the fluctuation of the nozzles 21 of the ink jet head 5, but the ink jet currently in general use is used. If a printing medium or ink for a printer is used, it is possible to sufficiently suppress this fluctuation.

When the widths D of the bleeds 33a and 33b of the black bars 31a and 31b in FIG. 5 are D1 and D2, respectively, the widths D1 and D2 are calculated by the following equations: D1 = B1-X1 * P = A + P * (X1-1) -X1 * P = A-P D2 = B2-X2 * P = A + P * (X2-1) -X2 * P = A-P, which results in " If D1 = D2 ", the bleeding is about the same even if the print line widths of the black bars 31a and 31b are different. Therefore, irrespective of the number of nozzles, as shown in FIG. 7, it can be obtained by measuring the print line width A when printing with one nozzle.

Therefore, when the width of the space 32 is F,
The space 32 is the width "Y" of the number of nozzles that do not eject ink.
Since it is the width obtained by subtracting the width D of the bleed 33 from * P ", the following equation holds.

F = Y * P−D = Y * P− (A−P) = P * (Y + 1) −A (2) In the equation (2), Y is the number of nozzles that do not eject ink. As described above, the line width B of the black bar 31 and the line width F of the space 32 corresponding to the number X of nozzles to be printed can be obtained.

Next, when actually printing a bar code,
A means for determining the number X of nozzles for printing the predetermined line width of the black bar 31 defined by the type and magnification of the barcode will be described.

First, assuming that the prescribed line width of the black bar 31 to be printed is C, when "| CB-" is the smallest,
That is, X when “C = B” or “C≈B”
Is the number of printing nozzles of the black bar 31.

Since the line width of the space 32 also differs depending on the type and magnification of the bar code, the required space 3
The number of nozzles must be determined for every two. From this, when the prescribed line width of the space 32 to be printed is C ′,
When "| C'-F |" is the smallest, that is, "C '
The bar code can be printed by setting Y when “= F” or “C′≈F” to the number of nozzles in the space 32 that are not ejected continuously.

FIG. 8 shows the bar code at each magnification of the ITF standard of 300 based on the result obtained from the result of FIG.
6 shows an example of a result of obtaining print control data when printing is performed using the ink jet head 5 having a nozzle resolution of dpi.

Also, this is obtained for a bar code of a specific code system, that is, an ITF code.
The same setting can be made regardless of the type and resolution of other barcodes.

Next, referring to the flowchart of FIG. 9, the process of controlling the printing of the ink jet head 5 for printing a predetermined bar code when the bar code print data is actually input to the ink jet printer 1 will be described. Explain.

First, the bar code print parameter input section 4
By this, the value of the line width A when printing with one nozzle shown in FIG. 7, the data of the resolution of printing to be printed with the ink jet head 5, the magnification of the bar code to be used, and the type of bar code are respectively input (step. S1). Step S1
This implements a print width data acceptance means and a resolution data acceptance means. Of the input data, the bar code magnification and bar code type data are used to determine the black bar required for bar code printing from the specified bar code values stored in the ROM of the printer controller 2 or the like. The line widths of 31 and space 32 are derived (step S
2).

Further, the dot pitch P is obtained from the resolution by the following equation (3) (step S3) (this realizes the dot pitch calculating means), P = 25.4 / resolution (3) And the value of the line width A are substituted into the equations (1) and (2), and the number of nozzles X in the equation (1) is arbitrary numerical value k, and the number of nozzles Y in the equation (2) is arbitrary numerical value m. (Step S
4), "| C-B | = [alpha] 2", "| C'-F | = [beta] 2"
Is derived (step S5). Similarly, by substituting arbitrary numerical values k-1 and k + 1 for the number X of nozzles of the equation (1) and arbitrary numerical values m-1 and m + 1 for the number of nozzles Y of the equation (2) (steps S6 and S8), Α1, α3, respectively
β1 and β3 are derived (steps S7 and S9).

At this time, if "α1> α2 <α3" and "β1> β2 <β3" are not satisfied (N in step S10), the process returns to steps S4, S6, S8 again, and the values of k and m are returned. Is changed to another value, and the processing from step S4 onward is repeated. “Α1> α2 <α3” and “β
When 1> β2 <β3 ”holds (Y in step S10), the numerical values of k and m become the number X of printing nozzles of the black bar 31 and the number Y of nozzles of the space 32, respectively (step S11). , S6, S8 realize the print line width calculating means, space width calculating means, print line width calculating step, space width calculating step, and steps S5, S7, S
9, the first and second nozzle number calculation means by S10,
The first and second nozzle number calculation steps are realized.

Here, the barcode code is input from the printer controller 2 to the print dot pattern generation circuit 6 (step S15), and a dot pattern is created (step S16). Then, in the printer controller 2, the ejection volume of ink required for printing and the transport speed of the print medium a are calculated from the resolution input in step S1, and print control data is output to the head drive circuit 7 based on these. A control signal is output to the mechanism control circuit 8 to print a barcode on the print medium a (step S17). The printing means and printing process are realized by step S17.

FIG. 10 is an enlarged plan view (a) of the orifice surface 22 when the ink jet head 5 is tilted by a predetermined angle θ with respect to the conveyance direction of the print medium a, and an enlarged plan view of the printing result at this time. It is (b). The printer controller 2 derives the dot pitch P from the input resolution by using the formula (3) (step S1).
2) From this, when the determined nozzle pitch T of the inkjet head 5 is equal to the dot pitch P (N in step S13), the angle of the inkjet head 5 is left unchanged at the angle θ = 0, but T When> P (Y in step S13), the inkjet head 5 is tilted by the angle θ represented by the following equation (4) with respect to the relative conveyance direction with respect to the print medium a (step S14).
The comparison means is realized by step S13, and step S1
4 realizes the control means.

[0074]

[Equation 1]

That is, as shown in FIG.
The rotary shaft 14 is attached to the rotary shaft 14
Is rotated by an angle θ by an actuator (not shown) by the mechanism control circuit 8. That is, it moves from the state of FIG. 11 (a) to the state of FIG. 11 (b). This realizes a head drive mechanism.

As described above, by inclining the inkjet head 5 by the angle θ, it is possible to print at a pitch narrower than the nozzle pitch T of the inkjet head 5. That is, a higher resolution barcode can be printed. In addition, since the resolution is changed by inclining the ink jet head 5 in this manner, the ejection volume required for printing and the transport speed of the print medium a also correspond to the conditions when the inkjet head 5 is inclined by the angle θ. Change to printing conditions.

In the above description, the case where the number of nozzles X is 1 is described as the minimum printing unit. However, in addition to this, for example, when printing a relatively large-sized bar code, the minimum printing unit is Alternatively, the number of nozzles X may be set to be such that two adjacent nozzles 21 are used as one unit for printing. In this case, for example, when the number of nozzles is 10, the number of nozzles X is counted as 5.

As is clear from the above description, according to the ink jet printer 1, when a bar code is printed using the ink jet head 5, even if the print is smeared on the print medium a, the print is recorded with high accuracy. You can

[0079]

According to the first aspect of the present invention, in consideration of ink bleeding when printing on a print medium by an ink jet system, images of a plurality of consecutive lines such as a bar code are printed with a desired line width. It is possible to set the number of nozzles that eject or do not eject the ink of the inkjet head necessary for forming the line and the space between the lines even if the printing medium and the ink are different, and a plurality of nozzles can be set with desired accuracy. Line images can be printed.

According to a second aspect of the present invention, in the ink jet printer according to the first aspect, the number of nozzles for ejecting ink of the ink jet head necessary for forming a line is set, and an image of a plurality of lines is formed with desired accuracy. Can be printed.

According to a third aspect of the present invention, in the ink jet printer according to the first or second aspect, the number of nozzles that do not eject the ink of the ink jet head necessary for forming a space between the lines is set to obtain a desired accuracy. Images of multiple lines can be printed.

According to a fourth aspect of the present invention, in the ink jet printer according to any one of the first to third aspects, the ink of the ink jet head necessary for forming the line and the space between the lines even if the resolution is different. It is possible to set the number of nozzles that eject or not eject, and it is possible to print an image of a plurality of lines with desired accuracy.

According to a fifth aspect of the invention, in the ink jet printer according to the fourth aspect, it is possible to print at a pitch narrower than the nozzle pitch of the ink jet head, and it is possible to print a high resolution image.

According to a sixth aspect of the invention, in consideration of ink bleeding when printing on a print medium by an ink jet system,
Images such as barcodes that are lined up in a row can be printed with a desired line width, and even if the print media and ink are different, the ink of the inkjet head that is necessary to form the line and the space between the lines It is possible to set the number of nozzles that eject or not eject, and it is possible to print an image of a plurality of lines with desired accuracy.

According to a seventh aspect of the present invention, in the nozzle number calculating method according to the sixth aspect, the number of nozzles for ejecting ink of the ink jet head necessary for forming the line is set, and the number of nozzles of a plurality of lines is set with desired accuracy. Images can be printed.

According to an eighth aspect of the present invention, in the nozzle number calculation method according to the sixth or seventh aspect, the number of nozzles that do not eject ink of the ink jet head required for forming a space between lines is set to a desired value. Images of multiple lines can be printed with high accuracy.

According to the invention of claim 9, in consideration of ink bleeding when printing on a print medium by an ink jet system,
Images such as barcodes that are lined up in a row can be printed with a desired line width, and even if the print media and ink are different, the ink of the inkjet head that is necessary to form the line and the space between the lines It is possible to set the number of nozzles that eject or not eject, and it is possible to print an image of a plurality of lines with desired accuracy.

According to a tenth aspect of the present invention, in the ink jet printing method according to the ninth aspect, ink bleeding when printing on a print medium by an ink jet method is taken into consideration,
Bar code image can be printed with desired line width,
Even if the print medium and ink are different, it is possible to set the number of nozzles that eject or do not eject the ink of the inkjet head required to form the black bar of the barcode and the space between the black bars, and the bar can be set with the desired accuracy. The image of the code can be printed.

In the eleventh aspect of the present invention, it is possible to provide a bar code printed with a desired line width in consideration of ink bleeding when printing on a print medium by an ink jet system, and to provide a print medium, To provide a bar code printed with desired accuracy by setting the number of nozzles that eject or do not eject the ink of the inkjet head required to form the black bar and the space between the black bars even if the ink is different. You can

According to a twelfth aspect of the invention, in the print medium according to the eleventh aspect, the number of nozzles that do not eject ink of the ink jet head necessary for forming the space between the black bars is set, and printing is performed with desired accuracy. We can provide the barcode.

According to a thirteenth aspect of the present invention, in the print medium according to the eleventh or the twelfth aspect, the number of nozzles that do not eject the ink of the ink jet head necessary for forming the space between the black bars is set to obtain a desired accuracy. We can provide barcodes printed in.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an inkjet printer according to an embodiment of the present invention.

FIG. 2 is a perspective view of an ink jet head portion of the inkjet printer.

FIG. 3 is an enlarged plan view (a) of an orifice surface of the ink jet head, and an enlarged plan view (b) of dots ejected from the orifice surface and printed.

FIG. 4 is an enlarged plan view (a) of an orifice surface of the inkjet head, and an enlarged plan view (b) of a barcode formed by ejecting ink from the orifice surface.

FIG. 5 is an enlarged plan view of a barcode printed by the inkjet method.

FIG. 6 is an explanatory diagram of a result of measuring a print width when actually printing on a print medium with an inkjet printer and verifying a variation of the print width.

FIG. 7 is an enlarged plan view illustrating measurement of a print line width when printing with one nozzle by an inkjet printer.

8 is an ITF based on the results obtained from the results of FIG.
FIG. 6 is an explanatory diagram showing an example of a result of obtaining print control data when a barcode at each standard magnification is printed using an inkjet head having a nozzle resolution of 300 dpi.

FIG. 9 is a flowchart illustrating a process performed by the inkjet printer.

FIG. 10 is an enlarged plan view (a) of an orifice surface when the inkjet head is tilted by a predetermined angle θ with respect to a print medium conveyance direction, and an enlarged plan view (b) of a printing result at this time. .

FIG. 11 is a perspective view illustrating a mechanism for rotating the inkjet head.

[Explanation of symbols]

1 inkjet printer 5 inkjet head 14 Head drive mechanism 21 nozzles 23 dots 31 black bar 32 spaces 33 Bleeding P dot pitch T nozzle pitch a print media

Claims (13)

[Claims] 1. An inkjet printer for performing printing on a print medium by an inkjet head in which a plurality of nozzles for ejecting ink are arranged in a line at a predetermined pitch, wherein 1 of the inkjet head is used by using a predetermined print medium and ink. Printing width A when printing with one of the above nozzles
Print width data receiving means for receiving the above data, and using the dot pitch P and the print width A when the dot pitch when printed by the inkjet head is P (where A> P), the inkjet head The print line width B when ink is ejected from X continuous nozzles to print a plurality of lines that are continuously arranged is as follows: B = A + P * (X-1) (1) The printing line width calculating means which is obtained by performing the above calculation, and "| C-B" where C is the specified line width of the line.
The first nozzle number calculation means for calculating the number X of nozzles when || becomes the minimum, and the width of the space between the lines formed by not ejecting ink from the continuous Y nozzles is F. When F = P * (Y + 1) -A (2), the space width calculation means for calculating the space width F is calculated, and the specified width of the space is C ′. To "| C'-F
Second nozzle number calculation means for calculating the number Y of nozzles when || becomes the minimum, and the plurality of lines are printed using the number of nozzles X and Y obtained by the first and second nozzle number calculation means. And a printing unit that drives the inkjet head to perform printing according to the print control data. 2. The first nozzle number calculating means substitutes N-1, N, N + 1 into the nozzle number X in the equation (1), where N is a continuous arbitrary integer, and " B (N-1)
> B (N) <B (N + 1) ”, N is“ | C−
The inkjet printer according to claim 1, wherein the number of nozzles X is calculated when B | "is minimum. 3. The second nozzle number calculating means substitutes N-1, N, N + 1 into the nozzle number Y in the equation (2), where N is a continuous arbitrary integer, and " F (N-1)
> | F (N) <F (N + 1) ”
3. The ink jet printer according to claim 1, wherein the number is calculated as the number of nozzles Y when -F | "is minimum. 4. A resolution data receiving means for receiving data of a resolution used for printing, and a dot pitch calculating means for obtaining the dot pitch P based on this resolution. The inkjet printer according to any one of 1. 5. A head drive mechanism that drives the inkjet head to change the arrangement direction of the nozzles with respect to the print medium, a dot pitch P obtained by the dot pitch calculation means, and a nozzle pitch T of the inkjet head. The inkjet printer according to claim 4, further comprising: comparison means for comparing and control means for controlling the head driving mechanism according to a result of the comparison to perform a predetermined amount of the change. 6. The inkjet method for printing a plurality of continuously arranged lines by an inkjet method of printing on a print medium by an inkjet head in which a plurality of nozzles for ejecting ink are arranged in a line at a predetermined pitch. In the nozzle number calculation method for obtaining the number of consecutive nozzles that eject ink from the head to print the line and the number of consecutive nozzles that form the space between the lines by not ejecting ink from the nozzles, When the printing width when printing with one or a plurality of the nozzles of the inkjet head using a medium and ink is A and the dot pitch when printing with the inkjet head is P, the dot pitch P and the printing are performed. Ink is ejected when printing the line using the width A and (where A> P) When the number of nozzles to be printed is X, the print line width B when printing the line is obtained by performing the calculation of the equation (1) B = A + P * (X-1) (1). When the calculation process and the prescribed line width of the line are C, "| CB
A first nozzle number calculation step of calculating the number of nozzles X when | ”becomes the minimum, and when the number of nozzles that do not eject ink forming the space is Y, and the width of the space is set to F , F = P * (Y + 1) -A (2) The space width calculation step of calculating the space width F by performing the calculation of the formula (2), and "|| C'-F
And a second nozzle number calculating step of calculating the nozzle number Y when | ”becomes the minimum. 7. The first nozzle number calculating step substitutes N−1, N, N + 1 into the nozzle number X of the equation (1), where N is a continuous arbitrary integer, and then, B (N-1)
> B (N) <B (N + 1) ”, N is“ | C−
7. The nozzle number calculation method according to claim 6, wherein the number of nozzles is calculated as the number of nozzles X when B | ”becomes the minimum. 8. The second nozzle number calculating step substitutes N−1, N, N + 1 into the nozzle number Y of the equation (2), where N is a continuous arbitrary integer, and then, F (N-1)
> | F (N) <F (N + 1) ”
The nozzle number calculation method according to claim 6 or 7, wherein the number of nozzles is calculated as Y when the number of -F | "is minimized. 9. An ink jet printing method for printing on a print medium by an ink jet head in which a plurality of nozzles for ejecting ink are arranged in a line at a predetermined pitch, according to any one of claims 6 to 8. A printing step of creating print control data for printing the plurality of lines by using the nozzle numbers X and Y obtained by the nozzle number calculation method, and driving the inkjet head by the print control data to perform printing. And an inkjet printing method. 10. The inkjet printing method according to claim 9, wherein in the printing step, a bar code is printed as the plurality of lines. 11. A printing medium in which a bar code composed of a plurality of black bars continuously arranged is printed by an inkjet method, and a dot pitch of the printing of the bar code is P, and the inkjet used for printing the bar code. Assuming that the print width when printing with one or more of the nozzles of the head is A and assuming that the number of continuous nozzles of the inkjet head that ejected ink when printing the black bar is X , Using the print width A and the dot pitch P (where A> P), the print line width B of the black bar is expressed by the following equation (1): B = A + P * (X-1) (1) In other words, the number of dots of the black bar is “| C−B, where C is the specified line width of the black bar.
| ”Is equal to the number of nozzles X when the space is minimum, and assuming that the number of consecutive nozzles of the inkjet head that does not eject ink when forming this space is Y, the space between the black bars When the width F of the space is expressed by the equation (2) F = P * (Y + 1) -A (2), the number of dots forming the space is "when the defined width of the space is C '. The number of nozzles Y when | C'-F | "is minimum
A print medium characterized by being equal to. 12. The number X of nozzles when “| CB−” is the minimum is N−1, N, N + 1 in the formula (1), where N is an arbitrary continuous integer. Substituting for the number of nozzles X, "B (N-1)> B (N) <B (N + 1)"
The print medium according to claim 11, wherein the print medium is equal to N when 13. The number Y of nozzles when "| C'-F |" is a minimum is expressed by the formula (2), where N-1, N, N + 1 are defined as N, where N is a continuous arbitrary integer. Substituting into the number Y of nozzles of “F (N−1)> F (N) <F (N + 1)”
The print medium according to claim 11 or 12, wherein N at which