JP6341206B2 - Inkjet dyeing method - Google Patents

Description

  The present invention relates to an inkjet dyeing method.

  Ink jet heads that generate pressure in the pressure chamber by the operation of the pressure applying means and eject ink from the pressure chamber from the nozzles are required to record at higher speed and with higher precision, and the number of nozzles and nozzle rows is increasing. It tends to increase. Along with this, there is a problem of an increase in crosstalk that makes a droplet velocity (amount of droplets) unstable because a pressure wave generated in a pressure chamber during ejection propagates to another pressure chamber.

  The instability of the droplet velocity due to crosstalk is caused by the pressure wave generated in the pressure chamber during ejection propagating from the inlet side of the pressure chamber to the common ink chamber and affecting other pressure chambers via the common ink chamber. It is generated by exerting. In particular, in the case of an inkjet head having two or more rows of pressure chambers, and the pressure chambers of each pressure chamber row communicate with each other through a common ink chamber, the pressure wave is transmitted to the other pressure chambers via the common ink chamber. Since it also propagates to each pressure chamber in the row, it is important to suppress crosstalk between the rows of pressure chambers.

  With regard to the problem of crosstalk, Patent Document 1 discloses that a common ink chamber is divided into two along a row of pressure chambers by a separation wall, and a pressure wave propagates from one pressure chamber row to the other pressure chamber row. It is described to prevent. Further, in Patent Document 2, the wall surface of the common ink chamber facing the inlet of the pressure chamber is defined to have a predetermined volume modulus or less, thereby attenuating the pressure wave propagated into the common ink chamber and causing crosstalk. It is described to reduce.

JP 2003-11368 A JP 2007-168185 A

  Furthermore, when crosstalk occurs in the inkjet head, there is a problem that satellites are easily generated in the ink droplets ejected from the inkjet head. When a satellite is generated when an image having a high ejection frequency (such as a solid image) is printed, the probability that the generated satellite adheres to the nozzle surface of the inkjet head increases. When satellites adhere to the vicinity of the nozzle on the nozzle surface, the amount of liquid droplets ejected from the nozzles is different from the set amount, the liquid droplet ejection direction is different from the set direction, and no liquid droplets are ejected from the nozzles. Or As a result, the printed image is defective.

  Furthermore, if the ink applied by the ink jet head is an ink containing a disperse dye with many coarse particles or an ink having a high thixotropic index, there is a problem that satellites are likely to be generated. The generation mechanism of the satellite is not particularly limited, but the coarse particles inhibit the formation of a predetermined droplet, and if the thixotropic index is high, the satellite may be separated from an appropriate applied voltage during high-speed continuous driving and low-speed intermittent driving. This is likely to occur.

  The present invention provides a means for improving the ejection stability from an ink jet head in a method of ink jet dyeing with an ink containing a disperse dye. More specifically, the frequency of nozzle missing is reduced in inkjet dyeing with high ejection frequency.

The present invention relates to the following inkjet dyeing method.
[1] An inkjet dyeing method in which an ink containing at least a disperse dye, a dispersant, water, and a water-soluble organic solvent is ejected from an inkjet head and recorded on a fiber,
The number ratio of disperse dye particles having a particle diameter of 5 μm or more to the total number of disperse dye particles contained in the ink is 5% or less,
The inkjet head has two or more rows in which pressure chambers for generating pressure for ejecting ink from the nozzles by pressure applying means that operates by applying a driving signal are arranged, and the pressure chambers are common to each other Communicated by the ink chamber,
The row in which the pressure chambers are arranged is divided into N drive groups (N is an integer of 2 or more), and for each drive group, the drive signal to be applied to the pressure applying unit of the pressure chamber is expressed as nAL + t ( However, n is an integer of 1 or more, AL is 1/2 of the acoustic resonance period of the pressure wave in the pressure chamber, and t is obtained by “distance between nozzles between drive groups” / “speed at which sound is transmitted through the ink”. An ink jet dyeing method that gives a phase difference in the pressure wave transmission time.
[2] The inkjet dyeing method according to [1], wherein adjacent rows of the pressure chambers are set to drive groups different from each other.
[3] The inkjet dyeing method according to [1] or [2], wherein the thixotropic index of the ink is 1.2 or less.

  According to the inkjet dyeing method of the present invention, the occurrence of satellites and the occurrence of missing nozzles (a phenomenon in which droplets are not ejected from the nozzles) are suppressed, and injection stability is improved. Therefore, it is possible to improve the quality of an image with a high injection frequency (such as a solid image).

The figure which shows schematic structure of an inkjet recording device Exploded perspective view showing schematic configuration of inkjet head Partial rear view of the head chip shown in FIG. Partial sectional view of the head chip The figure which shows an example of the drive signal used for this invention The figure explaining the deformation | transformation operation | movement of the partition by the drive signal shown in FIG. Front view of head chip showing a division mode of drive groups of two channel rows Timing chart of drive signal applied to each drive group shown in FIG. Graph explaining the relationship between fluctuation of droplet velocity and Delay [AL] The figure explaining the drive timing between several channel rows Front view of a head chip showing a division mode of drive groups of four channel rows Timing chart of drive signals applied to each drive group shown in FIG. Front view of head chip showing division mode of drive group of six channel rows Timing chart of drive signals applied to each drive group shown in FIG. The figure explaining the aspect by which a some channel row | line is driven by a some drive circuit

  In the inkjet dyeing method of the present invention, an inkjet ink containing at least a disperse dye, a dispersant, water, and a water-soluble organic solvent is ejected from an inkjet head to dye fibers.

1. Inkjet ink The ink used in the inkjet dyeing method of the present invention contains at least a disperse dye, a dispersant, water, and a water-soluble organic solvent.

1-1. Disperse dye The ink used in the inkjet dyeing method of the present invention contains a disperse dye as a coloring material. The disperse dye is a nonionic dye having no ionic water-soluble group such as sulfonic acid or carboxy group, and has low solubility in water. Therefore, it is finely powdered, and is usually dispersed in water by a dispersant and blended in the ink. Unlike pigments, disperse dyes are soluble in organic solvents such as acetone and dimethylformamide. Moreover, it is possible to diffuse and color in a synthetic fiber in a molecular form. Inks containing disperse dyes are used for dyeing synthetic fibers, for example.

  Specific compounds of preferred disperse dyes are shown below. However, it is not limited to the compound illustrated to these.

  [C. I. Disperse Yellow] 3, 4, 5, 7, 9, 13, 23, 24, 30, 33, 34, 42, 44, 49, 50, 51, 54, 56, 58, 60, 63, 64, 66, 68 71, 74, 76, 79, 82, 83, 85, 86, 88, 90, 91, 93, 98, 99, 100, 104, 108, 114, 116, 118, 119, 122, 124, 126, 135 140, 141, 149, 160, 162, 163, 164, 165, 179, 180, 182, 183, 184, 186, 192, 198, 199, 202, 204, 210, 211, 215, 216, 218, 224 , 227, 231, 232

  [C. I. Disperse Orange] 1, 3, 5, 7, 11, 13, 17, 20, 21, 25, 29, 30, 31, 32, 33, 37, 38, 42, 43, 44, 45, 46, 47, 48 49, 50, 53, 54, 55, 56, 57, 58, 59, 61, 66, 71, 73, 76, 78, 80, 89, 90, 91, 93, 96, 97, 119, 127, 130 , 139, 142

  [C. I. Disperse Red] 1, 4, 5, 7, 11, 12, 13, 15, 17, 27, 43, 44, 50, 52, 53, 54, 55, 56, 58, 59, 60, 65, 72, 73 74, 75, 76, 78, 81, 82, 86, 88, 90, 91, 92, 93, 96, 103, 105, 106, 107, 108, 110, 111, 113, 117, 118, 121, 122 , 126, 127, 128, 131, 132, 134, 135, 137, 143, 145, 146, 151, 152, 153, 154, 157, 159, 164, 167, 169, 177, 179, 181, 183, 184 , 185, 188, 189, 190, 191, 192, 200, 201, 202, 203, 205, 206, 207, 210, 221, 224, 22 5,227,229,239,240,257,258,277,278,279,281,288,298,302,303,310,311,312,320,324,328

  [C. I. Disperse Violet] 1, 4, 8, 23, 26, 27, 28, 31, 33, 35, 36, 38, 40, 43, 46, 48, 50, 51, 52, 56, 57, 59, 61, 63 , 69, 77

  [C. I. Disperse Green] 9

  [C. I. Disperse Brown] 1, 2, 4, 9, 13, 19

  [C. I. Disperse Blue] 3, 7, 9, 14, 16, 19, 20, 26, 27, 35, 43, 44, 54, 55, 56, 58, 60, 62, 64, 71, 72, 73, 75, 79 81, 82, 83, 87, 91, 93, 94, 95, 96, 102, 106, 108, 112, 113, 115, 118, 120, 122, 125, 128, 130, 139, 141, 142, 143 , 146, 148, 149, 153, 154, 158, 165, 167, 171, 173, 174, 176, 181, 183, 185, 186, 187, 189, 197, 198, 200, 201, 205, 207, 211 , 214, 224, 225, 257, 259, 267, 268, 270, 284, 285, 287, 288, 291, 293, 295, 297, 301, 315, 330, 333, 373

[C. I. Disperse Black] 1, 3, 10, 24

  In the dyeing process, when the dye is colored by high-temperature treatment, it is preferable to select a disperse dye having good sublimation fastness because the dye does not cause contamination due to the dye sublimating on the white background of the machine or fabric.

  0.1-20 mass% is preferable and, as for content of the disperse dye in an ink, 0.2-13 mass% is more preferable. The disperse dye may be used as a commercial product, but it is preferable to carry out a purification treatment. As a purification method, a known recrystallization method, washing or the like can be used. The organic solvent used in the purification method and purification treatment is preferably selected as appropriate according to the type of dye.

  The particle diameter of the disperse dye is preferably 300 nm or less as the volume average particle diameter and 900 nm or less as the maximum particle diameter. When the volume average particle size and the maximum particle size exceed the above ranges, clogging is likely to occur in the ink jet printing method in which light is emitted from a fine nozzle, and stable emission is not possible. The volume average particle size can be determined by a commercially available particle size measuring device using a light scattering method, an electrophoresis method, a laser Doppler method, or the like. Examples include sizer 1000.

  The ratio of the number of disperse dye particles having a particle diameter of 5 μm or more to the total number of disperse dye particles contained in the ink is preferably 5% or less, and more preferably 1% or less. Furthermore, the ratio of the number of disperse dye particles having a particle diameter of 2 μm or more to the total number of disperse dye particles contained in the ink is preferably 5% or less, and more preferably 1% or less.

  The number ratio of disperse dye particles with a particle size of 5 μm or more is measured by measuring the total number of disperse dye particles and the number of disperse dye particles with a particle size of 5 μm or more using an in-liquid particle counter (for example, HIAC-8000A manufactured by Hach Company). Then, it can be obtained from the ratio.

1-2. Dispersant The dispersant contained in the ink used in the ink jet dyeing method of the present invention is preferably a polymer dispersant, a low molecular surfactant or the like. Examples of polymer dispersants include natural rubbers such as gum arabic and tragacanth, glucosides such as saponin, cellulose derivatives such as methylcellulose, carboxycellulose and hydroxymethylcellulose, natural polymers such as lignin sulfonate and shellac, poly Acrylate, salt of styrene-acrylic acid copolymer, salt of vinylnaphthalene-maleic acid copolymer, sodium salt of β-naphthalenesulfonic acid formalin condensate, anionic polymer such as phosphate and polyvinyl alcohol And nonionic polymers such as polyvinylpyrrolidone and polyethylene glycol.

  The dispersant is preferably a dispersant having a carboxyl group, and these dispersants are available as commercial products, such as lignin sulfonate (for example, Vanillex RN, manufactured by Nippon Paper Industries Co., Ltd.), α- Polymeric dispersants such as copolymers of olefin and maleic anhydride (for example, Florene G-700, manufactured by Kyoeisha Chemical Co., Ltd.), Sankies (manufactured by Nippon Paper Industries Co., Ltd.), and the like.

  The content of the dispersant including the polymer dispersant is preferably 20 to 200% by mass with respect to the disperse dye. If the amount of the dispersing agent is small, the ability to make the dispersed dyes into fine particles and the dispersion stability become insufficient. Conversely, if the content of the dispersing agent is large, the formation of fine particles and the dispersion stability are inferior, and the ink viscosity is undesirably increased. These dispersants may be used alone or in combination.

  The dispersant is preferably a dispersant in which the ratio of the number of moles of carboxyl groups is 50 mol% or more with respect to the total number of acidic dissociable groups in the dispersant, and more preferably the ratio of moles of carboxyl groups is 80 mol% or more. More preferably, the ratio of the number of moles of carboxyl groups is 80 mol% or more and 100 mol% or less. By using a dispersant having a carboxyl group molar ratio as defined above, the effects of the present invention including ejection stability and the like are more effectively exhibited.

  The acidic dissociable group possessed by the dispersant in the present invention is also called a proton dissociable group, and examples thereof include a carboxyl group, a sulfo group, a sulfato group, a phosphono group, an alkylsulfonylcarbamoyl group, an acylcarbamoyl group, and an acylsulfamoyl group. Groups, alkylsulfonylsulfamoyl groups, and the like.

  Low molecular surfactants as dispersants include, for example, anionic surfactants such as fatty acid salts, higher alcohol sulfates, liquid fatty acid sulfates, alkylallyl sulfonates, polyoxyethylene alkyl ethers, sorbitan alkyls. Nonionic surfactants such as esters and polyoxyethylene sorbitan alkyl esters are exemplified. Each of these compounds can be used by selecting one or two or more appropriately. The content of the low molecular surfactant as a dispersant is preferably in the range of 1 to 20% by mass with respect to the total mass of the ink.

1-3. Water-soluble organic solvent Examples of the water-soluble organic solvent contained in the ink used in the inkjet dyeing method of the present invention include polyhydric alcohols (for example, ethylene glycol, glycerin, 2-ethyl-2- (hydroxymethyl) -1 , 3-propanediol, tetraethylene glycol, triethylene glycol, tripropylene glycol, 1,2,4-butanetriol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, 1,6-hexanediol, 1,2- Hexanediol, 1,5-pentanediol, 1,2-pentanediol, 2,2-dimethyl-1,3-propanediol, 2-methyl-2,4-pentanediol, 3-methyl-1,5-pentane Diol, 3-methyl-1,3-butanediol, 2-methyl-1,3-propanediol, etc.), (Eg, ethanolamine, 2- (dimethylamino) ethanol, etc.), monohydric alcohols (eg, methanol, ethanol, butanol, etc.), polyhydric alcohol alkyl ethers (eg, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether) , Triethylene glycol monomethyl ether, triethylene glycol monobutyl ether, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, etc.), 2,2'-thiodiethanol, amide (For example, N, N-dimethylformamide, etc.), heterocyclic rings (2-pyrrolidone, etc.), acetonitrile, etc. It is included. The amount of the water-soluble organic solvent relative to the total ink mass is preferably 10 to 60% by mass.

1-4. Water The water contained in the ink used in the inkjet dyeing method of the present invention may be ion exchange water. The amount of water relative to the total ink mass is usually 20% by mass or more and less than 60% by mass, but is not particularly limited.

1-5. Other Components The ink used in the inkjet dyeing method of the present invention may contain other optional components such as surfactants, inorganic salts, preservatives, antifungal agents, and dyeing aids.

  As the surfactant, any of cationic, anionic, amphoteric and nonionic can be used. Examples of the cationic surfactant include aliphatic amine salts, aliphatic quaternary ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, and the like. Anionic surfactants include fatty acid soap, N-acyl-N-methylglycine salt, N-acyl-N-methyl-β-alanine salt, N-acyl glutamate, alkyl ether carboxylate, acylated peptide , Alkyl sulfonate, alkyl benzene sulfonate, alkyl naphthalene sulfonate, dialkyl sulfosuccinate, alkyl sulfoacetate, α-olefin sulfonate, N-acylmethyl taurine, sulfated oil, higher alcohol sulfate Salts, secondary higher alcohol sulfates, alkyl ether sulfates, secondary higher alcohol ethoxy sulfates, polyoxyethylene alkylphenyl ether sulfates, monoglyculates, fatty acid alkylolamide sulfates, alkyl ether phosphates Salt, alkyl Acid ester salts. Examples of amphoteric surfactants include carboxybetaine type, sulfobetaine type, aminocarboxylate, imidazolinium betaine and the like. Nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene secondary alcohol ether, polyoxyethylene alkylphenyl ether (eg, Emulgen 911), polyoxyethylene sterol ether, polyoxyethylene lanolin derivative, polyoxy Ethylene polyoxypropylene alkyl ether (for example, Newpol PE-62), polyoxyethylene glycerin fatty acid ester, polyoxyethylene castor oil, hydrogenated castor oil, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, polyethylene glycol fatty acid Esters, fatty acid monoglycerides, polyglycerol fatty acid esters, sorbitan fatty acid esters, propylene glycol fatty acid esters , Sucrose fatty acid esters, fatty acid alkanolamides, polyoxyethylene fatty acid amides, polyoxyethylene alkyl amines, alkyl amine oxides, acetylene glycol, acetylene alcohol, and the like. The present invention is not limited to these.

  When these surfactants are used, they can be used alone or in combination of two or more, and are added in the range of 0.001 to 3.0% by mass with respect to the total amount of the ink.

  In the present invention, nonionic surfactants or anionic surfactants are preferred, and particularly preferred is sodium dodecylbenzenesulfonate, sodium 2-ethylhexylsulfosuccinate, sodium alkylnaphthalenesulfonate, and ethylene oxide addition of phenol. The product is an ethylene oxide adduct of acetylenediol.

  An inorganic salt may be added to the ink in order to keep the viscosity and dye of the ink stable or to improve color development. Examples of inorganic salts include sodium chloride, sodium sulfate, magnesium chloride, magnesium sulfide and the like. When implementing this invention, it is not limited to these.

  In order to maintain the long-term storage stability of the ink, an antiseptic and an antifungal agent may be added to the ink. Examples of the antiseptic and antifungal agent include aromatic halogen compounds (for example, Preventol CMK), methylene dithiocyanate, halogen-containing nitrogen sulfur compounds, 1,2-benzisothiazolin-3-one (for example, PROXEL GXL) and the like. . The present invention is not limited to these.

1-6. Ink thixotropic index The thixotropic index of the ink used in the inkjet dyeing method of the present invention is preferably 1.2 or less, and more preferably 1.1 or less. The thixotropic index means a ratio “viscosity value A / viscosity value B” between the viscosity value A at a shear rate of 100 / sec and the viscosity value B at a shear rate of 1000 / sec. Viscosity value A and viscosity value B can each be measured using a rotational rheometer (for example, MCR-300 manufactured by Anton Paar) at a measurement temperature of 25 ° C.

2. Inkjet Head and Inkjet Device The inkjet dyeing method of the present invention is usually performed using an inkjet recording apparatus equipped with an inkjet head. FIG. 1 is a schematic configuration diagram illustrating an example of an inkjet recording apparatus including an inkjet head.

  The ink jet recording apparatus 100 includes a transport roller pair 201 of the transport mechanism 200 that sandwiches the recording medium P. Further, the ink jet recording apparatus 100 includes a transport roller 203 that is rotationally driven by a transport motor 202. The recording medium P is transported in the Y direction (sub-scanning direction) by a pair of transport rollers 201 and a transport roller 203.

  The ink jet recording apparatus 100 includes an ink jet head H disposed between the transport roller 203 and the transport roller pair 201 so as to face the recording surface PS of the recording medium P. The inkjet head H is mounted and mounted on the carriage 400 so that the nozzle surface side faces the recording surface PS of the recording medium P. The carriage 400 is illustrated along the guide rail 300 spanned across the width direction of the recording medium P by driving means (not illustrated) that is substantially orthogonal to the conveyance direction (sub-scanning direction) of the recording medium P. It is provided so that it can reciprocate in the 'direction (main scanning direction). As will be described later in detail, the inkjet head H is electrically connected to the drive device 500 via an FPC (flexible printed circuit board) 4.

  The ink jet head H scans and moves the recording surface PS of the recording medium P in the X-X ′ direction in the drawing as the carriage 400 moves in the main scanning direction. A desired image is recorded by ejecting droplets from the nozzles during the scanning movement.

  2 to 4 show examples of the inkjet head H that is preferably used. 2 is an exploded perspective view of the inkjet head, FIG. 3 is a partial rear view of the head chip, and FIG. 4 is a partial cross-sectional view of the head chip.

  The inkjet head H shown in FIGS. 2 to 4 includes a so-called harmonica type head chip 1, a nozzle plate 2, a wiring board 3, an FPC 4, and an ink manifold 5.

  The head chip 1 has a hexahedral shape, and has two channel rows (A row and B row) in which a plurality of channels are arranged. In the channel row of the head chip 1, drive channels 11 that discharge ink as pressure chambers and dummy channels 12 that do not discharge ink are alternately arranged. The head chip 1 is an independent drive type head chip that performs recording by ejecting ink only from the drive channel 11.

  Of the two channel columns, the drive channel arranged in the A column is 11A, and the dummy channel arranged in the A column is 12A. Further, the drive channel arranged in the B column of the two channel columns is referred to as 11B, and the dummy channel arranged in the B column is referred to as 12B.

  In each channel row (A row or B row), drive channels (11A, 11B) and dummy channels (12A, 12B) are alternately arranged. The partition wall 13 between the drive channel (11A, 11B) and the dummy channel (12A, 12B) adjacent to each other serves as a pressure applying unit made of a piezoelectric element such as PZT. Hereinafter, the A-row partition walls may be referred to as 13A, and the B-row partition walls may be referred to as 13B.

  Each drive channel (11A, 11B) and each dummy channel (12A, 12B) are opened to the front end face 1a and the rear end face 1b of the head chip 1, respectively. In the inkjet head H shown in FIG. 2, the end surface of the head chip 1 on the ink ejection side is referred to as “front end surface 1 a”, and the opposite end surface is referred to as “rear end surface 1 b”.

  A drive electrode 14 is formed in close contact with the inner surface of each channel (11A, 11B, 12A, 12B). The outlet of each channel is provided on the front end face 1 a of the head chip 1, and the inlet is provided on the rear end face 1 b of the head chip 1. Each channel is formed in a straight shape from the inlet to the outlet.

  On the rear end surface 1b of the head chip 1, connection electrodes (15A, 15B) are formed. One end of the connection electrode (15A, 15B) is electrically connected to the drive electrode in the corresponding drive channel 11A, 11B or dummy channel 12A, 12B. Further, the connection electrode 15A extends from the inside of each channel 11A, 12A to one end edge 1c of the head chip 1. The connection electrode 15B extends from the inside of each channel 11B, 12B toward the A column side, and extends to the front of the channel column of the A column. Thus, both of the connection electrodes 15A and 15B extend in the same direction from the respective channels (11A, 11B, 12A, and 12B).

  The nozzle plate 2 is bonded to the front end surface 1a of the head chip 1 with an adhesive. In the nozzle plate 2, nozzles 21 are opened only at positions corresponding to the respective drive channels 11A and 11B.

  The wiring substrate 3 is a flat substrate larger than the rear end surface 1 b of the head chip 1. Through holes 32 </ b> A and 32 </ b> B are individually provided in a bonding region (region indicated by a one-dot chain line in FIG. 2) 31 of the wiring substrate 3 that is bonded to the rear end surface 1 b of the head chip 1. The positions of the through holes 32A and 32B correspond to the drive channels 11A and 11B opened on the rear end surface 1b of the head chip 1. Ink is supplied into the drive channels (11A, 11B) from the common ink chamber 51 of the ink manifold 5 through the through holes 32A, 32B.

  The common ink chamber 51 is configured by an internal space of a box-type ink manifold 5 that is bonded to the back side of the wiring board 3 (the side opposite to the head chip 1). The ink in the common ink chamber 51 is supplied to the drive channels 11A and 11B through the through holes 32A and 32B. Accordingly, the drive channels 11A and 11B communicate with each other via the common ink chamber 51. Further, the dummy channels 12 </ b> A and 12 </ b> B are blocked by the wiring substrate 3 and do not communicate with the common ink chamber 51.

  Further, on the surface of the wiring substrate 3, wiring electrodes 33A and 33B are formed which are electrically connected to the connection electrodes 15A and 15B arranged on the rear end surface 1b of the head chip 1. The wiring electrodes 33 </ b> A and 33 </ b> B extend in a direction orthogonal to the channel columns (A column and B column) of the head chip 1 on the surface of the wiring substrate 3. The wiring electrodes 33A and 33B are arranged alternately. The wiring electrodes 33A and 33B are formed by vapor deposition or sputtering.

  One end of the wiring electrode 33A corresponding to the connection electrode 15A drawn from the channels 11A and 12A arranged in the A row is located in the vicinity corresponding to each channel 11A, 12A in the A row in the bonding region 31. The wiring electrode 33 </ b> A extends from the bonding region 31 in a direction orthogonal to the channel row of the head chip 1 and extends to the end 3 a of the wiring substrate 3.

  On the other hand, one end of the wiring electrode 33B corresponding to the connection electrode 15B drawn from the channels 11B and 12B arranged in the B row is located in the vicinity corresponding to each of the channels 11B and 12B in the B row in the junction region 31. Further, the wiring electrode 33B extends in the same direction as the wiring electrode 33A, and extends to the end portion 3a of the wiring substrate 3 through between the adjacent through holes 32A in the A row.

  The wiring board 3 is bonded to the rear end surface 1b of the head chip 1, and the connection electrodes (15A, 15B) of the head chip 1 and the wiring electrodes (33A, 33B) of the wiring board 3 are electrically connected correspondingly. . The wiring board 3 and the head chip 1 are bonded with a predetermined pressing force (for example, 1 MPa or more) by an adhesive. The adhesive used may be an anisotropic conductive adhesive containing conductive particles, but is preferably an adhesive containing no conductive particles in order to increase the reliability of prevention of short circuit.

  The ink jet head H is mounted on the carriage 400 of the ink jet recording apparatus 100 so that the column direction of the channel rows (A row and B row) is along the Y direction in FIG. The inkjet head H is electrically connected to the driving device 500 via the FPC 4 (see FIG. 1). When a drive signal corresponding to the image data transmitted from the drive circuit in the drive device 500 is applied to the drive electrode 14 of each drive channel 11 via the FPC 4, the partition wall 13 is sheared and deformed. The volume is changed, and pressure for ejection is applied to the ink in the drive channel 11.

3. FIG. 5 shows an example of a drive signal given to the inkjet head H in order to eject ink from the nozzles 21 of the inkjet head H. This drive signal is a rectangular wave composed of a positive voltage (+ V) having a pulse width PW, and generates a negative pressure in the channel.

  The ink discharge operation of the inkjet head H by this drive signal will be described with reference to FIG. FIG. 6 shows one drive channel 11, two dummy channels 12 arranged on both sides thereof, and two partition walls 13 between them in one channel row of the inkjet head H.

  As shown in FIG. 6A, when the partition wall 13 between the drive channel 11 and the dummy channel 12 is in a neutral state, the drive signal shown in FIG. 5 is applied to the drive electrode 14 of the drive channel 11. Then, as shown in FIG. 6B, an electric field in a direction perpendicular to the polarization direction (indicated by an arrow in the figure) of the piezoelectric element forming the partition wall 13 is generated. As a result, both the partition walls 13 are sheared and deformed in a “<” shape toward each other, and the volume of the drive channel 11 is increased. Due to the deformation of the partition wall 13, the ink flows into the drive channel 11. After this deformed state is maintained for a predetermined pulse width PW, the drive signal returns to 0 potential. Then, pressure is applied to the ink in the drive channel 11 and droplets are ejected from the nozzle 21.

  The change in the ink pressure in the drive channel 11 caused by the deformation of the partition wall 13 is repeatedly reversed every 1 AL (Acoustic Length) such as “from negative to positive” and “from positive to negative”. For this reason, in order to eject droplets efficiently, the pulse width PW, which is the duration of the positive voltage of the drive signal, is set to the timing at which the pressure in the drive channel 11 changes from “negative to positive” and “from positive to negative. It is preferable to approximate the time difference (1AL) from the turning timing, and specifically, it is preferable to be in the range of 0.8 AL to 1.2 AL.

  AL indicating the duration of the drive signal refers to ½ of the acoustic resonance period of the pressure wave in the dummy channel 12. AL measures the velocity of a droplet discharged when a rectangular wave driving signal is applied to the driving electrode 14 and changes the rectangular wave pulse width PW while keeping the rectangular wave voltage value constant. It is determined as the pulse width that maximizes the droplet flight speed.

  A pulse is a rectangular wave having a constant voltage peak value. The pulse width PW is the time difference between the timing when the voltage rises from 0V to 10% and the timing when the voltage rises from the peak value voltage to 10% when 0V is 0% and the peak value voltage is 100%. Define.

  In the rectangular wave, both the time until the voltage rises from 10% to 90% and the time until the voltage falls from 90% to 10% are within 1/2 of AL, preferably 1/4. A waveform that is within.

  Next, a method in which the driving device 500 applies a driving signal to the inkjet head H will be described.

  The drive device 500 divides all the channel rows of the inkjet head H into N (N is an integer of 2 or more) drive groups and drives each independently.

  A drive signal from the drive device 500 is applied to the drive channels of the channel row belonging to one drive group at the same timing within the drive cycle T of the inkjet head H. Multiple drive trains may belong to one drive group. Each drive channel 11 and each dummy channel 12 included in one channel row are necessarily included in the same drive group.

  For example, the inkjet head H shown in FIG. 2 has two channel rows. Here, N = 2, and as shown in FIG. 7, the channel column of the A column is the drive group A, and the channel column of the B column is the drive group B. That is, all the channel rows of the inkjet head H are divided into two drive groups.

  In the inkjet head H, all the drive channels 11 belonging to the same drive group are simultaneously applied with drive signals.

  Between the drive signal applied to the drive electrode 14 of each drive channel 11 constituting the drive group A from the drive device 500 and the drive signal applied to the drive electrode 14 of each drive channel 11 constituting the drive group B As shown in the timing chart of FIG. 8, a phase difference “nAL + t” is given. Here, a drive signal is applied in the drive cycle T of the drive group A, and the drive group A is driven before the drive group B. n is an integer of 1 or more, and AL is ½ of the acoustic resonance period of the pressure wave in the drive channel 11 as described above. FIG. 8 illustrates the case where n = 1.

  Further, t is a pressure wave transmission time obtained by “a distance between nozzles between drive groups” / “a speed at which sound is transmitted through ink”.

  The “inter-nozzle distance between drive groups” between drive groups is between two drive groups to be driven with a phase difference. In the case of having two channel rows as shown in FIG. 7, the “distance between nozzles between drive groups” is the distance indicated by D in FIG.

  The speed C at which sound is transmitted through the ink can be calculated by the following equation. This speed C is a value unique to ink.

Ｋはインクの体積弾性率、ρはインクの密度である。

K is the volume modulus of the ink, and ρ is the density of the ink.

  The drive channel 11 A of the drive group A and the drive channel 11 B of the drive group B communicate with each other via the common ink chamber 51. Therefore, when a drive signal is applied to the drive electrode 14 of the drive channel 11A of the drive group A and the drive electrode 14 of the drive channel 11B of the drive group B to discharge the droplets, the droplets are affected by the influence of crosstalk. The speed may vary greatly. However, according to an experiment by the present inventor, for example, an inkjet head is configured such that droplets are ejected from the drive channel 11A of the drive group A and then ejected from the drive channel 11B of the drive group B after a predetermined delay time has elapsed. When H is driven, the droplet velocity ejected from the drive channel 11B of the drive group B periodically fluctuates according to the delay time with respect to the droplet velocity ejected from the drive channel 11A of the drive group A. Was found.

  As shown in FIG. 9, the droplet velocity ejected from the drive channel 11B repeatedly reverses positively or negatively every 1 AL after the “time lag” from the droplet ejection time of the drive group A. At the time of this inversion, the droplet velocity from the drive channel 11B of the drive group B becomes substantially the same as the droplet velocity from the drive channel 11A of the drive group A. Further, it has been found that the “time lag” from the time of droplet discharge of the drive group A corresponds to the above “time t”.

  That is, the droplet velocity from the drive channel 11B of the drive group B after the lapse of nAL + t from the time of droplet discharge from the drive channel 11A of the drive group A is substantially equal to the droplet velocity from the drive channel 11A of the drive group A. It turns out that it becomes the same speed.

  For this reason, the phase difference nAL + t is given between the drive signal applied to the drive group A and the drive signal applied to the drive group B, so that the head structure of the inkjet head H is not changed at all. The influence of crosstalk between the drive group A and the drive group B sharing the ink chamber 51 can be substantially ignored. That is, it is possible to suppress fluctuations in the droplet velocity between the channel rows. In addition, since a phase difference is given between the drive signal of the drive group A and the drive signal of the drive group B, the drive load is also suppressed.

  As shown in FIG. 9, the droplet velocity from the drive channel 11 of the drive group B is reversed to plus or minus every 1 AL after the elapse of time t. Therefore, n may be an integer of 1 or more. However, it is necessary to prevent a drive signal for ejection from a drive group to be driven later from overlapping the next drive cycle T. Also, if the value of n becomes too large, the difference in drive timing between different drive groups increases, which may cause a decrease in print speed. Therefore, from the viewpoint of speeding up printing, n is preferably as small as possible, and most preferably n = 1.

  In general, an inkjet head having a plurality of channel rows discharges droplets from the nozzles in advance at different timings in order to adjust the displacement of the landing position due to the difference in physical nozzle positions between adjacent channel rows. For example, in the inkjet head H having two channel rows, as shown in FIG. 10, the first row (for example, the drive group A) starts ejection at a certain physical position; Relative movement; nozzles 21 in the second row (drive group B) reach the physical position. Then, from the moment when the nozzles 21 in the second row (drive group B) arrive, the second row starts to discharge. Even in this case, each drive channel 11 normally discharges at the same drive timing, and only the start time and end time differ for each channel row.

  As described above, the phase difference nAL + t between the drive groups in the present invention is the difference between the start time and the end time (the landing position adjustment period between the drive groups) due to the landing position adjustment due to the difference in physical nozzle position between the drive groups. Delay time not included. That is, as shown in FIG. 10, the delay time provided in the period in which the two drive groups to which the phase difference is applied is driven together is shown. That is, the phase difference nAL + t is given to the application timing of the drive signal between the different drive groups A and B during the period in which the two drive groups are driven together. Thereby, the timing itself at which the droplets are ejected is different.

  Strictly speaking, since the phase difference nAL + t is given between the drive group A and the drive group B, there is a problem that it is necessary to adjust the landing position between the drive group A and the drive group B. Can be solved by adjusting the relative moving speed of the recording medium P and the inkjet head H.

  The above is a case where the ink jet head has two channel rows. In the present invention, the channel row of the inkjet head may be a plurality of rows. The plurality of channel rows can be divided into N drive groups (N is an integer of 2 or more) and driven in the same manner as described above.

  FIG. 11 shows the case where the inkjet head has four channel rows; the four channel rows are divided into two drive groups (drive group B with drive group A). Drive groups A and drive groups B are alternately arranged so that adjacent channel columns belong to different drive groups.

  In the embodiment shown in FIG. 11, D 'is preferably equal to D or large enough to attenuate the pressure wave sufficiently. Among these, “inter-nozzle distance between drive groups” is defined as D.

  The drive signal application timing at this time is given a phase difference of 1AL + t (when n = 1) between the drive group A and the drive group B, as shown in FIG. Thereby, it is possible to suppress the fluctuation of the droplet velocity between the drive groups A and B and reduce the drive load.

  FIG. 13 shows the case where the inkjet head has six channel rows; all six channel rows are divided into three drive groups (drive group A, drive group B, and drive group C). Yes. Adjacent channel columns are arranged in the order of drive groups A, B, C, A, B, and C so as to belong to different drive groups.

  In the embodiment shown in FIG. 13, D 'is preferably equal to D or large enough to attenuate the pressure wave sufficiently. Among these, “inter-nozzle distance between drive groups” is defined as D.

  As shown in FIG. 14, the drive signal application timing at this time is 1AL + t (n between the drive group A and the drive group B adjacent to each other and between the drive group B and the drive group C adjacent to each other. = 1) is provided. Thereby, it is possible to suppress the fluctuation of the droplet velocity between the driving groups A, B, and C and reduce the driving load.

  As described above, when the channel row is divided into three or more drive groups, it is preferable from the viewpoint of avoiding a decrease in print speed that all of the n in the phase difference nAL + t between the drive groups have the same value.

  When there are three or more channel columns, it is preferable that the drive groups of adjacent channel columns are different from each other. If at least one channel row belonging to a different drive group is arranged between channel rows belonging to the same drive group, the separation distance of the same drive group becomes large, so that the influence of crosstalk between the same drive groups is increased. To reduce.

  All the channel rows of the inkjet head H may not be driven by a common drive circuit in the drive device 500. The driving device 500 may include two or more driving circuits, and the channel strings of the respective driving groups may be driven by the two or more driving circuits. In this case, it is preferable that the channel columns driven by one drive circuit belong to different drive groups.

  FIG. 15 shows an example in which four channel rows of the inkjet head H are driven by two drive circuits (a drive circuit 501 and a drive circuit 502) in the drive device 500, two by two. In this case, the two channel columns driven by the drive circuit 501 belong to different drive groups (A and B). Similarly, the two channel columns driven by the drive circuit 502 belong to different drive groups (A and B). By doing so, it is possible to reduce the drop in the droplet velocity. This is because the load on the drive circuit is reduced by reducing the number of drive channels simultaneously driven by one drive circuit, and the waveform dullness of the drive signal can be reduced.

  In the above description, in order to generate a negative pressure in the dummy channel 12, the drive signal is a rectangular wave composed of a positive voltage (+ V) having a pulse width PW. However, the drive signal is not limited to this. Any drive signal may be used as long as it is a drive signal for discharging droplets.

  In the above description, the head chip 1 of the inkjet head H is a so-called “harmonic type head chip” having a hexagonal shape in which the inlet and outlet of the channel are arranged on opposite end faces. In the harmonica type head chip 1, the entrances of the drive channels 11 of all the channel rows are arranged on the rear end face 1 b, and the common ink chamber 51 is arranged on the entrance side of the drive channels 11. For this reason, the influence of crosstalk is relatively large, and fluctuations in droplet velocity are likely to occur. For this reason, the configuration of the present invention is a preferable aspect because a remarkable effect can be easily obtained. However, the head chip structure in the present invention is not necessarily limited to such a structure, and any pressure chamber may be used as long as the pressure chambers between the plurality of pressure chambers communicate with each other through a common ink chamber.

  In addition, the ink jet recording apparatus according to the present invention is not limited to one that performs recording by discharging droplets in the process of scanning and moving the ink jet head H in the width direction (main scanning direction) of the recording medium P (see FIG. 1). Instead, the inkjet head H is constituted by a line-shaped inkjet head fixed across the width direction of the recording medium P, and in the process of moving the recording medium P along the Y direction in FIG. The recording may be performed by discharging. In this case, the channel row of the inkjet head H is arranged along the X-X ′ direction in FIG. 1.

4). Regarding Dyeing Method The fiber dyed by the dyeing method of the present invention is not particularly limited as long as it is a fiber that can be dyed with a disperse dye, but among these, fibers such as polyester, acetate, and triacetate are preferable. Among these, polyester fiber is particularly preferable.

  The fiber to be dyed may be a fabric. The fabric may have any form such as a woven fabric, a knitted fabric, or a non-woven fabric. In addition, it is preferable that the fabric has 100% of fibers that can be dyed with disperse dyes. However, blended woven fabrics or blended nonwoven fabrics of rayon, cotton, polyurethane, acrylic, nylon, wool, silk, etc. are also used for printing. It can be used as a fabric. Further, the thickness of the yarn constituting the fabric as described above is preferably in the range of 10 to 100d.

  It is preferable that the dyeing | staining aid is contained in the fabric dye | stained by a high temperature steaming method. The dyeing aid forms an eutectic mixture with the water condensed in the form of cloth when the printing cloth is steamed, and has the effect of reducing the amount of moisture that re-evaporates and shortening the heating time. Further, this eutectic mixture has the effect of dissolving the dye on the fiber and promoting the diffusion rate of the dye into the fiber. An example of the dyeing aid is urea.

  The inkjet dyeing method of the present invention may be printing (inkjet printing).

  In the case of the inkjet dyeing method of the present invention, natural impurities (oil, fat, wax, pectin, natural pigment, etc.) attached to the fiber before pre-treating the fiber with water-soluble polymers to obtain a uniform dyed product, It is desirable to wash away residues of chemicals (such as glue) and dirt used in the fabric manufacturing process. As cleaning agents used for cleaning, alkalis such as sodium hydroxide and sodium carbonate, surfactants such as anionic surfactants and nonionic surfactants, enzymes and the like are used.

  In the inkjet dyeing method of the present invention, it is preferable to apply a pretreatment agent by a pad method, a coating method, a spray method or the like for the effect of preventing bleeding (pretreatment step). Thereafter, an image is formed on the fiber that can be dyed with a disperse dye by the ink jet recording method using the ink described above (ink application process), and then the fabric to which the ink is applied is heat-treated (coloring process). ) Further, by washing the heat-treated fabric (washing step), the printing on the fabric is completed, and a dyed product (printed product) is obtained.

  The pretreatment is not particularly limited as long as a method suitable for the fiber material or ink is appropriately selected from known methods such as treating the water-soluble polymer with fibers. For example, if it is used for a fiber provided with 0.2 to 50% by mass of at least one substance selected from the group consisting of a water-soluble metal salt, a polycation compound, a water-soluble polymer, a surfactant and a water repellent, A high degree of blur prevention is possible, and a high-definition image can be printed on a fabric, which is preferable.

  Examples of specific water-soluble polymers used for pretreatment include starches such as corn and wheat, cellulose derivatives such as carboxymethylcellulose, methylcellulose, and hydroxyethylcellulose, sodium alginate, guar gum, tamarind gum, locust bean gum And polysaccharides such as gum arabic, protein substances such as gelatin, casein and keratin, polyvinyl alcohol, polyvinyl pyrrolidone as synthetic water-soluble polymers, and acrylic acid polymers. Examples of the surfactant used for the pretreatment include anionic, cationic, amphoteric and nonionic ones. Typically, higher alcohol sulfates as anionic surfactants, sulfonates of naphthalene derivatives, etc .; quaternary ammonium salts as cationic surfactants, etc .; imidazoline derivatives as amphoteric surfactants And the like; and polyoxyethylene alkyl ethers, polyoxyethylene propylene block polymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, ethylene oxide adducts of acetylene alcohol, and the like as nonionic surfactants.

  Examples of the water repellent include silicon, fluorine-based and wax-based ones. These water-soluble polymers and surfactants previously imparted to the fabric do not cause dirt due to tarring when ink-jet printing and color development at high temperatures, and are therefore stable to high-temperature environments. preferable. Further, these water-soluble polymers and surfactants that are previously imparted to the fabric are preferably those that can be easily removed from the fabric by a washing treatment after ink-jet printing and color development at a high temperature.

  In the ink jet textile printing method for printing on a fabric, it is desirable to wind up the fabric printed after ink ejection, to develop color by heating, and to wash and dry the fabric. In ink-jet textile printing, ink is not satisfactorily dyed simply by leaving the ink printed on the fabric. In addition, when printing on a long fabric for a long time, the fabric comes out endlessly, so that the fabric printed on the floor is not only unoccupied but also unsafe, and unexpectedly dirty. May end up. Therefore, it is necessary to perform a winding operation after printing. During this operation, a medium not related to printing, such as paper, cloth, or vinyl, may be sandwiched between the cloth and the cloth. However, it is not always necessary to wind up when cutting in the middle or for a short fabric.

  The color development step is a step of developing the original hue of ink by adhering to and fixing the dye in the ink that has only adhered to the fabric surface after printing and is not sufficiently adsorbed and fixed to the fabric. As the coloring method, steaming by steam, baking by dry heat, thermosol, HT steamer by superheated steam, HP steamer by pressurized steam, etc. are used. They are appropriately selected depending on the material to be printed, ink, and the like. Further, the printed fabric may be immediately heat-treated or may be heat-treated after a while and may be dried and colored according to the intended use, and any method may be used in the present invention.

  In dyeing with a disperse dye, not only a method of developing a color at a high temperature but also a carrier may be used. The compound used as a carrier is preferably a compound having characteristics such as large dyeing acceleration, simple use, stable, low burden on human body and environment, easy removal from the fiber, and no influence on dye fastness. Examples of the carrier include o-phenylphenol, p-phenylphenol, methylnaphthalene, alkyl benzoate, alkyl salicylate, chlorobenzene, diphenyl such as diphenyl, ethers, organic acids, hydrocarbons and the like. These promote the swelling and plasticization of difficult-to-dye fibers that are difficult to dye at temperatures around 100 ° C. like polyester, and make it easier for disperse dyes to enter the fibers. The carrier may be preliminarily adsorbed on the fibers of the fabric used for inkjet printing, or may be included in the inkjet printing ink.

  A cleaning step is necessary after the heat treatment. This is because a dye that has not participated in dyeing remains, resulting in poor color stability and low fastness. It is also necessary to remove the pretreatment product applied to the fabric. If left as it is, not only the fastness is lowered, but also the fabric is discolored. Therefore, cleaning according to the object to be removed and the purpose is essential. The method is selected depending on the material and ink to be printed. For example, in the case of polyester, the treatment is generally performed with a mixed solution of caustic soda, a surfactant, and hydrosulfite. The method is usually carried out in a continuous type such as an open soaper or a batch type using a liquid dyeing machine, and any method may be used in the present invention.

  And after washing | cleaning, drying is required. After the washed fabric is squeezed or dehydrated, it is dried or dried using a dryer, heat roll, iron or the like.

  In the following, the invention will be described in more detail with reference to examples. The scope of the invention is not construed as being limited by the description of the examples.

[Example 1]
<Preparation of ink>
(Preparation of dye dispersions A1-A4, B1-B4, C1, D1, E1-E4, F1, G1)
A mixed liquid obtained by sequentially mixing the following additives was dispersed using a sand grinder to prepare a dye dispersion. At this time, during the dispersion treatment, the amount of coarse particles in a liquid particle counter (HIAC-8000A manufactured by Hach Company) was measured, and the dispersion treatment was terminated when a predetermined ratio was reached.

Dye (types listed in Table 1) 25 parts
30 parts glycerin dispersant (types and amounts listed in Table 1)
Amount required to make the total amount of ion-exchanged water 100 parts

(Preparation of inks A1-A4, B1-B4, C1, D1, E1-E4, F1, G1)
Inks A1-A4, B1-B4, C1, D1, E1-E4, F1, G1 were prepared using the dye dispersions prepared above according to the following prescription.

Dye dispersion 40 parts Ethylene glycol 15 parts Glycerine appropriate amount Sodium diethylhexyl sulfosuccinate Appropriate amount Proxel GXL (manufactured by AVECIA) 0.1 part Ion-exchanged water Amount required to finish the total amount to 100 parts

  The amount of glycerin was adjusted so that the viscosity of the ink was 5.7 mPa · s. An appropriate amount of sodium diethylhexylsulfosuccinate was added to adjust the surface tension of the ink to 41 mN / m. Thereafter, each ink prepared in a gas permeable hollow fiber membrane (Mitsubishi Rayon Co., Ltd.) is passed through, and the outer surface of the hollow fiber membrane is decompressed with a water aspirator to remove dissolved gases in the ink. did. In addition, after degassing, the vacuum pack was filled to prevent air from entering.

《Continuous injection test》
Using the prepared inks A1-A4, B1-B4, C1, D1, E1-E4, F1, and G1, a continuous ejection test was conducted with an inkjet apparatus.

  As shown in FIG. 11, an ink jet head having four ink jet head nozzle rows was prepared. All channel rows were divided into two drive groups A and B so that the drive groups differ between adjacent channel rows. Each channel row had 256 nozzles, and the inter-nozzle distance D between the channel rows in different drive groups was 0.846 mm and AL = 5.0 μs.

  The four channel rows of the inkjet head are driven by two drive circuits as shown in FIG.

As described above, the inks A1-A4, B1-B4, C1, D1, E1-E4, F1, and G1 have a viscosity of 5.7 mPa · s, a surface tension of 41 mN / m, and are transmitted through the ink. The speed of sound was 1600 m / s. From the above conditions, the pressure wave transmission time t obtained by “distance between nozzles between adjacent pressure chambers” / “speed at which sound is transmitted through ink” is 846 (μm) / 1600 × 10 ⁶ (μm / s) = 0.53 × 10 ⁻⁶ (s) = 0.53 (μs). From this calculated value, t = 0.5 (μs) was approximated.

  The drive signal applied to each drive channel from the drive device was a rectangular wave consisting only of the positive voltage (+ V) shown in FIG. The pulse width PW was 1 AL = 5.0 μs, and the driving period T was 100 μs. It is assumed that the drive signal is applied from a common drive device to all channel rows.

  The ink jet head was mounted on the carriage of the ink jet recording apparatus shown in FIG. The phase difference (nAL + t) between drive groups A and B is set to n = 1, and 1 × 5.0 + 0.9 = 5.9 μs, and the inkjet head is driven so that a drive signal is applied to drive group A first. Inkjet printing was performed.

<Stable injection property>
Continuous ejection test is performed by continually ejecting ink from all nozzles of the head used for 30 minutes or 60 minutes at full duty, and observing the occurrence of missing nozzles and the number of droplets adhering to the nozzle surface. Evaluation was performed. The results are shown in Table 2.
◎: No nozzle missing, no droplets attached ○: No nozzle missing, no more than 5 droplets attached △: No nozzle missing, no more than 20 droplets attached ×: Nozzle missing

<Crosstalk>
The droplets ejected from each nozzle of each drive group A and B were imaged using a camera. The droplet velocity was calculated by image processing the resulting droplet image. From the result, the average speed of each nozzle for each channel row was obtained. From the obtained average speed, | the average speed of drive group A−the average speed of drive group B | is calculated, and the fluctuation ratio to the average speed of drive group A is calculated from the calculated value (= calculated value / average speed of drive group A). × 100: unit%). The influence of crosstalk was evaluated according to the following criteria. The results are shown in Table 2.
◎: Less than 5% ○: 5% or more and less than 10% △: 10% or more and less than 15% ×: 15% or more

<Drive load>
Regarding the driving load for driving the ink jet head, nAL + t = 0, and the current value when driving all the driving channels without providing a phase difference in all the channel rows was set to 100, and the ratio (%) to the current value was obtained. The smaller the drive load value, the better. The results are shown in Table 2.

  As shown in Table 2, it was found that nozzles were missing in inks A1 and B1 in which the ratio of coarse particles of 5 μm or more was 6%, and ejection was not stable. On the other hand, in the inks in which the ratio of coarse particles of 5 μm or more is 3% or less, no nozzle missing occurred. However, inks A2 and B2 in which the ratio of coarse particles of 5 μm or more is 3% and ink C1 or C2 in which the ratio of coarse particles of 2 μm or more is 6% or 3% do not cause nozzle missing, but are not formed on the nozzle surface. A droplet adhered.

[Example 2]
(Preparation of dye dispersions H1 to H2)
After sequentially mixing the following additives, this mixed solution was dispersed using a sand grinder to prepare a disperse dye dispersion. At this time, during the dispersion process, the amount of coarse particles was measured using a submerged particle counter in the same manner as in Example 1, and the dispersion process was terminated when a predetermined ratio was reached.

Disperse dye (types listed in Table 3) 25 parts
30 parts glycerin dispersant (types and amounts listed in Table 1)
Amount required to make the total amount of ion-exchanged water 100 parts

(Preparation of ink H1-H2)
Ink H1-H2 was prepared according to the following formulation using the dye dispersion H1-H2 prepared above.

Disperse dye dispersion 40 parts Ethylene glycol 20 parts Glycerin appropriate amount Sodium diethylhexyl sulfosuccinate Appropriate amount Proxel GXL (manufactured by AVECIA) 0.1 part
Amount required to make the total amount of ion-exchanged water 100 parts

  The amount of glycerin was adjusted so that the viscosity of the ink was 10.0 mPa · s. An appropriate amount of sodium diethylhexylsulfosuccinate was added so that the surface tension of the ink was 32 mN / m. Thereafter, each ink prepared in a gas permeable hollow fiber membrane (Mitsubishi Rayon Co., Ltd.) is passed through, and the outer surface of the hollow fiber membrane is decompressed with a water aspirator to remove dissolved gases in the ink. did. In addition, after degassing, the vacuum pack was filled to prevent air from entering.

《Continuous injection test》
Using the prepared inks H1-H2, a continuous ejection test was performed with an ink jet apparatus.

  An ink jet head having two channel rows having the same structure as the ink jet head shown in FIG. 2 was prepared. One channel row was designated as drive group A, and the other channel row was designated as drive group B. Each channel row had 256 nozzles, and the inter-nozzle distance D between the channel rows was 1.128 mm and AL = 5.0 μs. The two channel rows of this inkjet head are driven by the same drive circuit.

As described above, the viscosity of the ink H1-H2 was 10 mPa · s, the surface tension was 32 mN / m, and the speed of sound transmitted through the ink was 1300 m / s. From the above conditions, the pressure wave transmission time t obtained by “distance between nozzles between drive groups” / “speed at which sound is transmitted through ink” is 1128 (μm) / 1300 × 10 ⁶ (μm / s) = 0. It is calculated as .87 × 10 ⁻⁶ (s) = 0.87 (μs). From this calculated value, t = 0.9 (μs) was approximated.

  As a drive signal applied to each drive channel from the drive device, a rectangular wave composed only of the positive voltage (+ V) shown in FIG. 5 was used. The pulse width PW was 1 AL = 5.0 μs, and the driving period T was 100 μs. It is assumed that the drive signal is applied from a common drive device to all channel rows.

<Drive condition 1>
This ink jet head is mounted on the carriage of the ink jet recording apparatus shown in FIG. 1, and the phase difference (nAL + t) between the drive groups A and B is n = 1, and 1 × 5.0 + 0.9 = 5.9 μs. The inkjet head was driven so that the drive signal was first applied to the drive group A.

<Drive condition 2>
In the same ink jet head as that in the driving condition 1, the phase difference between the driving groups A and B was not provided at all, and nAL + t = 0 was similarly evaluated for stable emission, crosstalk, and driving load. The results are shown in Table 4.

<Drive condition 3>
In the same ink jet head as that in driving condition 1, the same as in Example 1 except that the phase difference (nAL + t) is n = 0.5, t = 0, and 0.5 × 5.0 = 2.5 μs. Stable injection, crosstalk, and driving load were evaluated. The results are shown in Table 4.

  Evaluation of stable injection (continuous injection time was 120 minutes), crosstalk, and driving load was performed in the same manner as in Example 1.

  As shown in Table 4, under the driving condition 1, the injection was stable, no crosstalk was generated, and the driving load was suppressed. On the other hand, in the driving condition 2, since no phase difference was provided between the driving groups A and B, crosstalk occurred. In drive condition 3, crosstalk occurred because the phase difference between drive groups A and B was inappropriate.

  The ink jet dyeing method of the present invention can improve the ink ejection stability from the ink jet head. Therefore, a high quality inkjet dyeing thing is obtained.

H: Inkjet head 1: Head chip 1a: Front end surface 1b: Rear end surface 1c: Edge 11, 11, A, 11B: Drive channel (pressure chamber)
12, 12A, 12B: Dummy channel 13, 13A, 13B: Partition wall (pressure applying means)
14: Drive electrode 15A, 15B: Connection electrode 2: Nozzle plate 21: Nozzle 3: Wiring substrate 3a: End 31: Joining region 32A, 32B: Through hole 33A, 33B: Wiring electrode 4: FPC
5: Ink manifold 51: Common ink chamber 100: Inkjet recording apparatus 200: Conveying mechanism 201: Conveying roller pair 202: Conveying motor 203: Conveying roller 300: Guide rail 400: Carriage 500: Driving device 501, 502: Driving circuit

Claims (3)

An ink-jet dyeing method for recording an ink containing at least a disperse dye, a dispersant, water and a water-soluble organic solvent, ejected from an ink-jet head and recorded on a fiber,
The number ratio of disperse dye particles having a particle diameter of 5 μm or more to the total number of disperse dye particles contained in the ink is 5% or less,
The inkjet head has two or more rows in which pressure chambers for generating pressure for ejecting ink from the nozzles by pressure applying means that operates by applying a driving signal are arranged, and the pressure chambers are common to each other Communicated by the ink chamber,
The row in which the pressure chambers are arranged is divided into N drive groups (N is an integer of 2 or more), and for each drive group, the drive signal to be applied to the pressure applying unit of the pressure chamber is expressed as nAL + t ( However, n is an integer of 1 or more, AL is 1/2 of the acoustic resonance period of the pressure wave in the pressure chamber, and t is obtained by “distance between nozzles between drive groups” / “speed at which sound is transmitted through the ink”. An ink jet dyeing method that gives a phase difference in the pressure wave transmission time.   The inkjet dyeing method according to claim 1, wherein the adjacent rows of the pressure chambers are different drive groups.   The inkjet dyeing method according to claim 1 or 2, wherein the thixotropic index of the ink is 1.2 or less.

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