JP2000248217A - Method for ink jet recording, and recorded product obtained by the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the subject recording which is useful for recording images having high light-resistant fastness on wall paper as a building material, or the like, in a wide color reproducible range by specifying the kinds of dyes used for color inks and sensory chromaticity indexes when dyed with the color inks into single colors, respectively. SOLUTION: This method for ink jet recording comprises using at least four color inks having yellow, magenta, cyan and black colors, respectively, and extruding the inks on a recording medium in response to image signals. Therein, the inks I, II, III and IV wherein the kinds of the dyes used for the inks, respectively, and sensory chromaticity indexes a* and b* when dyed with the color inks in the single colors, respectively, have the following ranges in a color phase range [CIE 1976 (L*, a*, b*) are used. I yellow: acidic dye, a*=-20 to 20, b*=50 to 100; II magenta: reactive dye, a*=50 to 70, b*=-30 to 30; III cyan: reactive dye, a*, b*=-50 to -20, respectively; and IV black: acidic dye, a*, b*=-15 to 15, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink-jet recording method and a recorded matter using the same, and more particularly, to a method for producing a material having a sufficient color reproduction range, a wallpaper as a building material,
The present invention relates to an ink jet recording method for recording and creating an image or the like that requires high light fastness, such as synthetic leather such as a bag expected to be used outdoors, and a recorded matter obtained by the method.

[0002]

2. Description of the Related Art Conventionally, as a method of printing on a fabric such as cotton, silk, polyester, etc., a method called ink jet printing has been known in addition to screen printing and roller printing. This ink-jet printing is performed using an ink-jet image forming apparatus that forms an image on a recording medium such as plastic or recording paper, using an ink-jet printing apparatus that is configured in a form suitable for printing and a type of fabric. ing.

[0003] The ink jet system is one of low noise, non-impact systems in which ink is ejected and the ink or the like is directly attached to a cloth or the like. A printing apparatus equipped with an ink jet system recording head is a high density and high speed printing system. Operation is possible. Therefore, printing methods using plate making such as screens and engraving rolls are not suitable for high-mix low-volume production,
Ink-jet printing is a system without plate-making, and data to be printed can be easily formed by a host system or the like, so that high-mix low-volume production can be performed in a short time.

[0004] In general, an ink-jet printing apparatus is
A carriage on which a recording unit (print head) is mounted;
It is provided with transport means for transporting the fabric and control means for controlling these. Then, the recording head for ejecting ink droplets from the plurality of ejection ports is serially scanned in a direction (main scanning direction) orthogonal to the fabric conveying direction (sub-scanning direction), while the fabric is intermittently conveyed by a predetermined amount during non-printing. Things.

In this printing method, printing is performed by discharging ink onto a cloth in accordance with a print signal, and is attracting attention as a quiet printing method with a low running cost. Further, by using a print head in which a number of nozzles for ejecting ink are arranged in a straight line in the sub-scanning direction, the print head scans once on the fabric, thereby performing printing with a width corresponding to the number of nozzles. .

Further, in the case of multicolor printing (color printing), a color image is formed by overlapping ink droplets ejected by a plurality of color print heads.
Generally, when performing color printing, yellow (Y),
Four types of print heads and ink tanks corresponding to the three primary colors of magenta (M) and cyan (C), or the four primary colors including black (B) among these three primary colors are required.

Advantages of the ink jet textile printing apparatus are that the recording head can be easily made compact, high-definition images can be recorded at a high speed, running costs are low, and noise is reduced due to the non-impact method. In addition, it has the advantage that it is easy to record a color image having gradation using multi-color inks. The recording head uses a fine laser processing technology and semiconductor manufacturing technologies such as etching, steaming, and sputtering to form electrothermal transducers, electrodes, liquid path walls, and top plates that are formed on the substrate. Since it is possible to easily form an extremely high-density liquid passage / discharge port arrangement, it is possible to further reduce the size.

[0008]

However, in recent years, as the above-mentioned ink jet printing technology has begun to spread, only a conventional recording medium such as cloth (silk, cotton, wool, nylon, polyester, rayon, acrylic, etc.) has been used. For example, there is an increasing demand for forming images by ink jet recording on, for example, wallpaper in a room as a building material, or synthetic leather as a fabric such as a handbag, a bag, and shoes.

[0009] Of course, full-color image formation is desired. For example, in the case of conventional four-color reactive inks for printing yellow, magenta, cyan and black, the light fastness of yellow and black is particularly poor. Therefore, there is a problem that the yellow or black system color deteriorates after being left for a long period of time, and the saturation thereof is reduced.

On the other hand, in the case of conventional four color dye inks for printing yellow, magenta, cyan and black,
In particular, since magenta and cyan have poor light fastness, these colors deteriorate after being left for a long period of time, and there has been a problem that their chroma is reduced.

Although the cause is not fully understood, it is considered to be a basic characteristic of the reactive dyes and acid dyes currently used. That is, it is difficult to maintain the saturation after long-term storage compared to the initial stage. Therefore,
An object of the present invention is to solve the above-mentioned problems of the prior art and provide an ink jet recording method capable of forming an image having excellent light fastness on a recording medium, and an ink jet recorded matter having excellent light fastness. It is. Note that in the present invention described below, recording on a material other than a fabric is not strictly referred to as "textile printing", so that recording on a recording medium including the above-described fabric will be described below. Recording is performed by applying ink-jet printing techniques and apparatuses, and is referred to as an “ink-jet recording method”.

[0012]

The above objects are achieved by the present invention described below. That is, the present invention provides an ink-jet recording method in which at least four color inks of yellow, magenta, cyan, and black are used on a recording medium, and the recording is performed by discharging each color ink in accordance with an image signal. The dyes used and the perceived chromaticity indices a ^* and b ^* when dyed in a single color with each color ink are in the following range in the hue range [CIE1976 (L ^* , a ^* , b ^* ) space]. Provided are an inkjet recording method using inks I, II, III and IV, and a recorded matter obtained by the method. I yellow: acid dye, a ^* =-20 to 20, b ^* = 5
0-100 II Magenta: reactive dye, a ^* = 50-70, b ^* =-3
0-30 III cyan: reactive dye, a ^* =-50 to -20, b ^*
= -50 to -20 IV black: acid dye, a ^* =-15 to 15, b ^* =
-15 to 15

The present invention uses at least four color inks of yellow, magenta, cyan and black on a recording medium, and further uses at least one of five color inks of blue, violet, red, orange and green. In one type, in an ink jet recording method of performing recording by discharging each color ink according to an image signal, the type of dye used for each color ink, and the perceived chromaticity index a ^* when dyed with a single color with each color ink and b ^* is the hue range [CIE
1976 (L ^* , a ^* , b ^* ) space], the following ranges of dye inks I, II, III, IV, V, VI, VII, VIII
And IX, and a recorded matter obtained by the method. I yellow: acid dye, a ^* =-20 to 20, b ^* =
50-100 II Magenta: reactive dye, a ^* = 50-70, b ^* =-
30 to 30 III cyan: reactive dye, a ^* = − 50 to −20, b ^*
= -50 to -20 IV black: acid dye, a ^* =-15 to 15, b ^* =
-15 to 15 V blue: reactive dye, a ^* =-10 to 30, b ^* =
-60 to -30 VI violet: acid dye, a ^* = 20 to 70, b ^*
= -50 to -20 VII Orange: acid dye, a ^* = 20 to 70, b ^* = 5
0-90 VIII red: reactive dye, a ^* = 40-70, b ^* = 2
0-60 IX green: acid dye, a ^* =-70 to -20, b ^*
= 50-90

[0014]

Next, the present invention will be described in more detail with reference to preferred embodiments. A feature of the present invention is to form a color image having excellent light fastness on various recording media by using a combination of inks of four or more colors containing various dyes. In the present invention, when a color image is formed using four color inks of yellow, magenta, cyan, and black, by using the above-described inks I to IV as those inks,
An image having excellent light fastness is formed on the recording medium.
In the present invention, when a color image is formed by using at least one of the above-described inks of V to IX in addition to the above-described four color inks, the color is further improved on the recording medium in addition to the light fastness. An image having excellent reproducibility is formed.

Preferred specific examples of the dye used in the ink used in the present invention are as follows, and the reactive dye is magenta: CI Reactive Red 21, 22, 24, 2
9, 35, 45, 174, 180, 226, 218; Cyan: CIReactive Blue 15, 19, 21, 28,
49, 71, 72, 77, 195; Blue: CIReactive Blue 15, 19, 21, 38,
49, 72, 77, 176, 203, 220, 230,
235; Red: CIReactive Red 21, 22, 24, 29,
35, 45, 174, 180, 226, 218, 26
6; and the like.

As the acid dye, yellow: CI Acid Yellow 1, 7, 11, 17, 2
3, 25, 36, 38, 49, 72, 110, 127; Black: CIAcid Black 7, 24, 26, 29, 4
8, 52, 172; Violet: CIAcid Violet 5, 34, 43, 4
7, 48, 90, 103, 126; orange: CIAcid Orange 3, 19, 24, 28:
1, 33, 43, 45, 47, 51, 67, 94, 11
6, 127, 138, 145, 156; Green: CIAcid Green 16, 17, 19, 20,
25, 28, 40, 41, 71;

In the present invention, the dyes exemplified above are preferable because many dyes are used in conventional inks for ink jet recording, and the light fastness of these dyes is as follows.
It differs from dye to dye and from color to color. Further, when a color image is formed, although light fastness alone is excellent, light fastness often changes depending on how inks overlap on a recording medium. Although the differences and changes in these light fastnesses are not fully understood at present, the present inventors examined various dyes currently used, and found that yellow and black were more reactive than reactive dyes. It has been found that acid dyes have higher light fastness, and that of magenta and cyan, reactive dyes have higher light fastness than acid dyes.

From the result, for example, the hue range [CI
^{E1976 (L *, a *,} b *) space] small a ^* in, the b ^* large yellow, a ^* and b ^* acid dye ink has a higher lightfastness is subjected are small black, a ^* is large As the color becomes magenta, the light fastness of the acid dye ink becomes inferior, the light fastness of the reactive dye tends to improve, and as the value of b ^* becomes smaller than that of black, cyan becomes magenta. It has been found that reactive dyes tend to have higher light fastness than acid dyes as described above. The present invention is excellent in light fastness by selecting a dye to be used in an ink and determining the combination as described above based on the above findings, and can form a color image excellent in color reproducibility. I can do it.

The ink used in the present invention is prepared by adding the dye to an aqueous medium. The amount (solid content) of the dye in the ink is 1 to 30% by weight based on the total amount of the ink.
Is preferable. As the aqueous medium used together with the dye, water or a mixture of water and a water-soluble organic solvent is used. Preferred organic solvents include, for example, lower alkylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol, and propylene glycol. Ethylene glycol methyl (or ethyl, propyl, butyl) ether, diethylene glycol methyl (or ethyl, propyl, butyl) ether, triethylene glycol methyl (or ethyl, propyl, butyl) ether, propylene glycol methyl (or ethyl, propyl, butyl) ) Alkylene groups such as ether, dipropylene glycol methyl (or ethyl, propyl, butyl) ether and tripropylene glycol methyl (or ethyl, propyl, butyl) ether Lower alkyl ethers of coal; polyalkylene glycols such as polyethylene glycol and polypropylene glycol, and those in which one or two of the hydroxyl groups represented by mono- and dialkyl ethers are modified; glycerin, thiodiethylene glycol, sulfolane, N -Methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like. Usually, the content of the aqueous medium with respect to the total amount of the ink is preferably 0 to 50% by weight.

In the case of a water-based ink, the content of water as a main component is preferably in the range of 30 to 95% by weight based on the total weight of the ink. Further, as a constituent of the ink, urea or its derivative, a dispersant, a surfactant, a polyvinyl alcohol or a cellulose compound or sodium alginate as a viscosity adjusting agent, a pH adjusting agent, a fluorescent brightening agent as a clogging inhibitor, if necessary. It is possible to add a fungicide or the like.

The chromaticity of the above-described ink depends on the dye concentration of the ink described later, but is measured when the recording medium is dyed with a single color of about 2 to 40 cc per unit area (1 m 2). The perceived chromaticity indices a ^* and b ^{* of the} recorded matter are
In the hue range [CIE1976 (L ^* , a ^* , b ^* ) space], it means the above.

For the upper and lower limits of the color reproduction range of each color,
As an upper limit, a dye having a wider color reproduction range is not practical, and as a lower limit, various colors are basically reproduced by mixing the three primary colors of yellow, magenta and cyan. However, with an ink having a color reproduction range smaller than this, a sufficient color reproduction range cannot be obtained as a color reproduction range obtained by mixing two or more colors.

Further, blue, violet, orange, red, and green are adopted as colors that are difficult to express in the three primary colors of yellow, magenta, and cyan. There is no point in using the special feature. Further, black is not recognized as "black" unless it is within the above-described color reproduction range.

The correlation between the color of the ink and the type of the acid / reactive dye will be described again. As for the dye whose hue range is fixed within the above range when the dye is fixed on the recording medium, various dyes are used. For example, for yellow, the color is usually a ^* =-20 to 20, b ^* = 50 to
About 100 is required for a single color, but within that range, acid dyes have higher light fastness than reactive dyes.

The same is true for black, magenta, and cyan. In the above-mentioned hue range required as a single color, black has higher light fastness for acid dyes and black for reactive dye inks for magenta and cyan. Has higher light fastness.

Here, regarding blue and violet,
Although there is not much difference, violet has a larger b ^* value than blue and is more yellow than yellow, so acid dyes have better light fastness, blue is more reactive than cyan. Dyes have better light fastness.

Similarly, there is not much difference between orange and red. However, since orange is more yellow than yellow, acid dye has better light fastness, and red is more magenta than reactive dye. Is excellent.

The ink-jet recording method and apparatus used in the present invention may be any of conventionally known ones.
For example, there is a method and an apparatus for applying thermal energy corresponding to a recording signal to ink in a chamber of a recording head and generating droplets by the thermal energy. Alternatively, a method and apparatus for ejecting liquid droplets using the vibration of a piezo element can be used.

The recording medium used in the present invention can be, of course, plain paper or coated paper, or any cloth that does not require post-processing such as coloring or removal of excess ink. On a cloth as a base material, a vinyl chloride sheet in which a vinyl chloride layer, a urethane or acrylic layer and an ink receiving layer are laminated in this order, and by recording an image on this sheet by the above-described inkjet recording method. One of the objects of the present invention is realized. The ink recorded on such a recording medium by the method of the present invention is preferably subjected to a dye drying step. Although this drying method depends on the configuration of the ink receiving layer, drying with a heater or blowing warm air from above the ink receiving layer is almost sufficient.

It is possible to provide an overcoat layer for protecting the image of the recorded matter obtained as described above, more preferably after recording a desired image on the sheet. Further, the overcoat layer is a transparent acrylic resin layer, which protects the image obtained by the ink jet recording while transmitting the image, and performs an uneven process (a so-called emboss process) on the overcoat layer as necessary. It is also possible.

Further, by adding an ultraviolet absorber to the overcoat layer, the light fastness of an image can be improved. As the ultraviolet absorbent, for example, an inorganic compound such as cerium oxide or an organic compound such as a salicylic acid-based absorbent, a benzophenone-based absorbent, a benzotriazole-based absorbent, or a cyanoacrylate-based absorbent is used. The recorded matter of the present invention can be obtained by performing post-processing of the ink jet recording and the recording medium by such a method.

Next, a schematic configuration of an example of the ink jet recording apparatus used in the present invention will be described. Of course, the device to which the present invention can be applied is not limited to the following configuration, and it is also possible for those skilled in the art to add any structural changes or components that can be easily considered.

FIG. 1 is a schematic side sectional view showing a schematic configuration of a recording apparatus. Here, reference numeral 1 in the drawing denotes the recording medium as described above, which is unwound according to the rotation of the unwind roller 11, and
The printer unit 1000 via the intermediate rollers 13 and 15
After being conveyed in a substantially horizontal direction by a conveying unit 100 provided at a portion facing the sheet, the sheet is wound on a winding roller 21 via a feed roller 17 and an intermediate roller 19.

The transport section 100 generally transports transport rollers 110 and 120 provided upstream and downstream of the printer section 1000 in the transport direction of the recording medium 1 in the form of an endless belt wound between the rollers. A belt 130 and a pair of platen rollers 140 provided to expand the transport belt 130 with a suitable tension within a predetermined range to regulate the recording surface of the recording medium to be flat when recording by the printer unit 1000 and to improve flatness. And

Here, the transport belt 130 is made of a metal as disclosed in Japanese Patent Application Laid-Open No. H5-212851 in the apparatus shown in the figure, and is partially enlarged in FIG. On the surface thereof, an adhesive layer (sheet) 133 is provided. Then, the recording medium 1 is adhered to the transport belt 130 via the adhesive layer 133 by an attaching roller,
Flatness during recording is ensured.

The recording medium 1 conveyed in such a state where the flatness is secured is applied with ink by the printer unit 1000 in the area between the platen rollers 140, and the conveyance belt 130 or the adhesive The film is peeled off from the layer 133 and is wound up by the winding roller 21, and a drying process is performed by the drying heater 600 on the way. The form of the drying heater 600 can be appropriately selected, such as a type that blows warm air to the recording medium 1, a type that radiates infrared rays, or a combination thereof.

FIG. 2 shows the printer unit 1000 and the recording medium 1.
FIG. 2 is a perspective view schematically showing the transfer system of FIG.
The configuration of the printer unit 1000 will be described with reference to FIGS. First, in FIG. 1 and FIG. 2, the printer unit 1000 moves in a direction different from the transport direction (sub-scanning direction) f of the recording medium 1,
For example, it has a carriage 1010 that scans in the width direction S of the recording medium 1 perpendicular to the transport direction f. 1020
Reference numeral denotes a support rail extending in the S direction (main scanning direction), and supports a slide rail 1022 that supports and guides a slider 1012 fixed to a carriage 1010. Reference numeral 1030 denotes a motor serving as a drive source for performing main scanning of the carriage 1010, and the driving force is transmitted to the carriage 1010 via a belt 1032 to which the carriage 1010 is fixed and other appropriate transmission mechanisms.

The carriage 1010 moves the print head 1100 having a large number of nozzles that eject a large number of inks in a predetermined direction (in this case, the transport direction f) in a direction different from the predetermined direction (in this case, the main scanning direction S). The print head set is held in two steps in the transport direction in this case.

A plurality of print heads 1100 are provided as one set corresponding to inks of different colors.
This enables color printing. The color to be used and the number of print heads in one set can be appropriately selected according to an image to be formed on the recording medium 1 or the like.
For example, the three primary colors of printing, yellow (Y), magenta (M), and cyan (C), or a combination of black (Bk) and black (Bk) can be used. Alternatively, or in addition to them, special colors (metallic colors such as gold and silver, vivid red and blue, etc.) which cannot be expressed or are difficult to express in the three primary colors can be used in addition to the set. Alternatively, light color inks having the same color but different densities may be used.

In this case, a plurality of sets of print heads 1100 arranged in the main scanning direction S are provided in two stages, one set in the transport direction f, as shown in FIG. The colors, arrangement numbers, arrangement orders, and the like of the inks used by the print heads in each stage may be the same for each stage or may be different depending on the image to be recorded. In addition, printing can be performed again by the next-stage print head for an area printed by the main scan of the first-stage print head (complementary thinning printing is performed by the print heads of each stage). Or high-speed printing may be performed by sharing the recording area. Further, the number of print head stages is not limited to two, but may be one or three or more.

In these figures, the print head 1
As 100, an ink jet head, for example, a bubble jet head proposed by Canon Inc. having a heating element that generates heat energy that causes film boiling of the ink as energy used for discharging the ink is used. . Then, with respect to the recording medium 1 conveyed in a substantially horizontal direction by the conveyance unit 100, the recording medium 1 is used in a state where an ink ejection port as an ink applying element is directed downward,
As a result, the head difference between the discharge ports is eliminated, the discharge conditions are made uniform, good image formation is enabled, and a uniform recovery process for all the discharge rollers is enabled.

A flexible cable 1110 provided so as to follow the movement of the carriage 1010 is connected to each print head 1100, and various signals such as a head drive signal and a head state signal are exchanged with a control unit (not shown). Will be Further, ink is supplied to the print head 1100 via a flexible tube 1120 from an ink supply system 1130 containing the respective color inks.

FIG. 3 is a perspective view schematically showing an ink supply system in this embodiment. Ink supply system 1130
Is composed of two systems. That is, in the first system, the first system
The first ink supply tube 1120 joined to the set of ink storage tanks 1131 is a flexible tube 1
In the second system, the second ink supply tube 112 is also connected to the second ink storage tank 1132 through the inside of the ink supply tube 110 and to the head connection portion 1150.
1 is connected to the head joint 1150 through the flexible tube 1110. Here, the ink supply tubes 1120 and 1121 form a circulation path including the ink supply tubes 1120a and 1121a on the outward path and the ink supply tubes 1120b and 1211b on the return path, respectively.

Each of the ink storage tanks 1131 and 1132 has a pressure pump (not shown). The ink in the tank is pressurized by the pressure pump, and the ink is supplied to the ink supply tube shown in FIG. 1120a, 1211a
Through the print head 1100, and returns to the ink storage tanks 1131 and 1132 through the ink supply tubes 1120b and 1121b on the return path.

Further, the ink can be refilled in the ink supply tubes 1120 and 1121 by the pressure pump, and the ink is circulated in the head so that a part of the ink at this time flows out of the nozzle. By doing so, a head recovery operation can also be performed. Here, a plurality of ink storage tanks 1131 and 1132 are provided corresponding to inks of different colors, thereby enabling color printing.

The number of ink storage tanks in each set can be appropriately selected according to the image to be formed on the recording medium 1 and the like. For example, the three primary colors of printing are yellow (Y), magenta (M), and magenta (M). It can be cyan (C) or further added black (Bk). Alternatively, or in addition to these, it is possible to use a special color (metallic color such as gold or silver, or vivid red or blue) that cannot be expressed or is difficult with the three primary colors. Alternatively, even if the colors are the same, a plurality of inks may be used according to the density. Head joint 11
Reference numeral 50 includes a first set of head joints 1151 indicated by solid lines in FIG. 3, a second set of head joints 1152 indicated by broken lines, and a joint cover 1160.

Next, a schematic configuration of a head used in the above-described apparatus will be described with reference to FIG.
FIG. 4 is a cross-sectional perspective view illustrating a schematic configuration of an inkjet head mounted on an inkjet recording apparatus used in the present invention.

In this figure, the print head is constituted by a top plate 71 and a substrate 72 overlapping each other. Top plate 71
Has a plurality of grooves 73 serving as nozzles for passing ink, a groove 74 serving as a common liquid chamber communicating with these grooves, and a supply port 75 for supplying ink to the common liquid chamber. on the other hand,
The substrate 72 has an electrothermal transducer 76 corresponding to each nozzle and an electrode 77 for supplying power to each electrothermal transducer integrally formed by a film forming technique. Such a top plate 7
A plurality of ejection openings (orifices) 78 for ejecting ink are formed by combining the substrate 1 with the substrate 72.

Here, a brief description will be given of the above-described bubble jet type ink droplet forming process performed by the print head. First, when the heating resistor (heater) reaches a predetermined temperature, a film bubble covering the heater surface is generated. The internal pressure of this bubble is very high, pushing out the ink in the nozzle. The ink moves toward the common liquid chamber outside the nozzle and in the opposite direction by the inertial force of the extrusion. As the movement of the ink proceeds, the internal pressure of the bubble becomes negative, and the velocity of the ink inside the nozzle becomes slow due to the addition of flow path resistance. The ink ejected from the nozzle opening (orifice) to the outside is faster than the inside of the nozzle, so that constriction occurs due to the balance between the inertial force, the flow path resistance, the shrinkage of the bubble, and the ink surface tension, and the ink is separated / droplets. At the same time as the bubble is contracted, ink is supplied from the common liquid chamber into the nozzle by the capillary force and waits for the next pulse.

As described above, a print head (hereinafter, also referred to as an ink jet head) using an electrothermal transducer as an energy generating means (hereinafter, also referred to as an energy generating element) has a one-to-one correspondence with a driving electric pulse signal. Bubbles can be generated in the ink in the passage, and the growth and contraction of the bubbles can be performed immediately and appropriately, so that ink droplet ejection with particularly excellent responsiveness can be achieved.
In addition, it is easy to make the print head compact, and it is possible to make full use of the advantages of IC technology and macro processing technology, which have been significantly improved in reliability and reliability in recent semiconductor technology, and high-density mounting is possible. This is advantageous because it is easy and the manufacturing cost is low.

The conditions for obtaining a particularly effective recording method using the ink of the present invention are as follows.
６００600 dpi, ejection droplets 10１０〜200 pl, ink ejection amount ²量 40 nl / mm ² , drive frequency 1.5〜1
A condition of 0 kHz or more and a head temperature of 35 to 60 ° C. is preferable.

In the above configuration, the recording head 1100
When the recording head returns to the home position at the end of recording or the like, the cap (not shown) near the head home position is attached to the recording head 1.
100 is retracted from the movement path, but an elastic blade (not shown) protrudes into the movement path. As a result, the ejection port surface of the recording head 1100 is wiped by the elastic blade. When the cap is brought into contact with the ejection surface after the recording head 1100 stops to perform capping, the cap moves so as to protrude into the moving path of the recording head.

When the recording head 1100 moves from the recording start position to the home position, the cap and the blade are at the same position as the position at the time of wiping described above. As a result, the ejection port surface of the recording head 1100 is wiped during this movement. The above-described movement of the print head to the home position is performed not only at the end of printing or at the time of ejection recovery, but also at a predetermined interval while the print head moves through the printing area for printing to the home position adjacent to the printing area. Then, the wiping is performed along with this movement.

[0054]

Next, the present invention will be described more specifically with reference to examples and comparative examples. Examples and Comparative Examples Recording is performed on a vinyl chloride sheet (hereinafter, referred to as a PVC sheet) using the ink jet recording apparatus and the ink jet head shown in the drawings. As detailed description, (1) a method of manufacturing a PVC sheet, (2) components of ink used for recording (here, six colors of yellow, magenta, cyan, black, blue, and red are used), and (3) The inkjet recording apparatus for forming an image on a PVC sheet and the formation of an evaluation image will be described in more detail with respect to (4) post-processing such as formation of an overcoat layer after forming an image on a PVC sheet. Finally, since the evaluation for confirming the effect of the present invention is performed, (5) the evaluation method will also be described. Here, as a comparative example, the light fastness is evaluated by changing the type of the ink. Therefore, the used ink will be described at the point (2) at the same time.

(1) Description of Layer Structure of PVC Sheet and Method for Producing the Same Any paper or cloth (for a normal vinyl chloride sheet, number 1
(About 0 μm), a 150 μm thick vinyl chloride resin film is coated here on the base material, and the polyvinyl chloride sheet alone is soft, so that the strength is increased and the urethane resin is coated with a 20 μm thickness to improve the appearance. And an ink receiving layer having a thickness of 10 μm was applied on the urethane resin.
The ink receiving layer is a porous layer, for example, a layer obtained by adding a polymer binder to a water absorbing resin.

(2) Description of Ink for Inkjet Recording in the Present Invention The ink was prepared as follows. The weight of each ink was 100 parts. Reactive dye ink (magenta,
The composition of cyan, blue and red) is as follows. -10 parts of reactive dye-40 parts of thiodiglycol-50 parts of water The dye used was magenta: C.I. I. Reactive Red 24, Cyan: C.I. I. Reactive Blue 220, Blue: C.I. I. Reactive Blue 15, Red: C.I.
I. Reactive Red 266.

Acid dye ink (yellow and black)
Is as follows. -Acid dye 10 parts-Diethylene glycol 40 parts-Water 50 parts The dye used was yellow: C.I. I. Acid Yellow 1
10, black: C.I. I. Acid Black 26.

As a comparative example, evaluations described later were simultaneously made for a recording material prepared using a reactive dye ink (Comparative Example 1) and a recording material prepared using an acidic dye ink (Comparative Example 2). The ink used in this comparative example is also described here. As the reactive dye ink, in addition to the above, yellow: C.I. I. Reactive Yellow 95, Black: C.I. I. It was prepared using Reactive Black 39 in the same manner as in the above reactive dye ink. As the acid dye ink, in addition to the above, magenta: C.I. I. Acid Red 266, Cyan: C.I. I. Acid Blue 9, Blue: C.I. I. Acid Blue 90, Red: C.I. I. It was prepared in the same manner as in the above acid dye ink using Acid Red 27.

(3) The description of the ink jet recording apparatus is the same as that shown in the figure, so that the description is omitted here. With this apparatus, in order to evaluate the light fastness, an image of the highest density of each color (full ejection of each pixel at the highest recording density) was formed with a uniform evaluation patch.

(4) Post-Treatment and Formation of Overcoat Layer An image was formed on the recorded matter obtained through the above-described steps by blowing warm air at about 80 ° C. at an air velocity of 1 to 5 m / sec. The recording medium was sprayed from above, and then the recording medium was further passed over a heater plate at about 70 ° C. (Therefore, the heated surface by the heater plate was the surface on the side opposite to the image formation of the recording medium). In both cases, the recording medium was heated at the image forming speed for the time required for the recording medium to pass through the air flow or for the time required for the recording medium to pass over the heater plate.

Thereafter, the ink receiving layer of the obtained recorded matter,
As a result, an overcoat layer having a role of protecting the image itself is formed as follows. The overcoat layer needs to be transparent so that the formed image can be transmitted,
Acrylic resin was used as a binder. Here, 0.5 part by weight of cerium oxide was added as an ultraviolet absorber, and it was confirmed that the transparency was not impaired. Further, depending on the required design, it is possible to apply embossing or the like on this overcoat layer to give a texture, but here, in order to evaluate the following light fastness, embossing of the surface Has not gone.

(5) Evaluation of recorded matter The recorded matter obtained as described above had the following tint before the test.

[Table 1]

Regarding the light fastness of the recorded matter, see JI
Using a xenon arc lamp type light resistance tester specified in SB7754, the sample is continuously irradiated with a xenon arc lamp for 20 hours, and the judgment is made according to JIS L08.
A light fastness test was performed in which the test was performed using a gray scale for discoloration and fading specified in No. 04. Judgment is 5
Grade = almost no change to grade 1 = almost fading, but in the image sample of the present invention, the light fastness was judged as follows:
Each of the colors was about the fourth grade, which was a level having no problem in practical use.

On the other hand, with respect to the light fastness of the recorded matter of Comparative Examples 1 and 2, in Comparative Example 1, yellow fading was particularly severe (judgment = 1st to 2nd grade), and it was not usable.
Further, in Comparative Example 2, magenta fading was particularly severe (judgment: first and second grades), which was also unsuitable for use.

[0065]

As described above, according to the present invention, the chromaticity of each color ink,
Saturation is defined so that a sufficient color reproduction range can be obtained.In each color reproduction range, an ink with higher light fastness is used as an acid dye for yellow and black, and a reactive dye for magenta and cyan. For example, inks with excellent light fastness are used together to complement each color with low fastness in reactive ink and acidic ink, so create recorded matter using such inks Thus, it is possible to provide an ink-jet image which is excellent in light fastness, can withstand color reproduction of an initial image, can withstand long-term use or use outdoors, and can maintain its saturation. In particular, in the present invention, by forming a color image on a recording medium that is often used outdoors such as a sheet of vinyl chloride, it has excellent light fastness and the color saturation of the image is maintained for a long time. The effect is obtained.

[Brief description of the drawings]

FIG. 1 is a schematic side sectional view showing a schematic configuration of an ink jet recording apparatus to which the present invention is applied.

FIG. 2 is a perspective view schematically showing a printer unit and a transport unit of FIG.

FIG. 3 is a schematic perspective view of an ink supply system in the apparatus of FIG.

FIG. 4 is a perspective view for explaining a schematic configuration of a print head mounted on the apparatus of FIG.

[Explanation of symbols]

 1: recording medium 100: transport unit 1000: printer unit 1010: carriage 1100: print head 1130: ink supply system 1140: connecting member 1150: head joining unit 1160: joining unit cover

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Katsushi Hara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Taku Yokozawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon In-house F term (reference) 2C056 EA13 FC02 HA44 4J039 AD09 AD10 BA13 BC16 BC19 BC29 BC44 BC52 BC66 BE04 BE33 EA15 EA16 EA17 EA19 EA20 EA21 EA35 FA02 FA03 GA24 GA25

Claims (7)

[Claims] 1. An ink jet recording method in which at least four color inks of yellow, magenta, cyan and black are used on a recording medium and each color ink is ejected in accordance with an image signal to perform recording. The types of dyes and the perceived chromaticity indices a ^* and b ^* when dyed in a single color with each color ink are in the hue range [CIE1976
(L ^* , a ^* , b ^* ) space], using the dye inks I, II, III and IV in the following ranges. I yellow: acid dye, a ^* =-20 to 20, b ^* =
50-100 II Magenta: reactive dye, a ^* = 50-70, b ^* =-
30 to 30 III cyan: reactive dye, a ^* = − 50 to −20, b ^*
= -50 to -20 IV black: acid dye, a ^* =-15 to 15, b ^* =
-15 to 15 2. A recording medium using at least four color inks of yellow, magenta, cyan and black, and using at least one of five color inks of blue, violet, red, orange and green. In the ink jet recording method of discharging and recording each color ink according to the image signal, the type of dye used for each color ink, and the perceived chromaticity index a ^* and b ^* when dyed with a single color with each color ink, Hue range [CIE1976
(L ^* , a ^* , b ^* ) space], using the dye inks I, II, III, IV, V, VI, VII, VIII and IX in the following ranges. I yellow: acid dye, a ^* =-20 to 20, b ^* =
50-100 II Magenta: reactive dye, a ^* = 50-70, b ^* =-
30 to 30 III cyan: reactive dye, a ^* = − 50 to −20, b ^*
= -50 to -20 IV black: acid dye, a ^* =-15 to 15, b ^* =
-15 to 15 V blue: reactive dye, a ^* =-10 to 30, b ^* =
-60 to -30 VI violet: acid dye, a ^* = 20 to 70, b ^*
= -50 to -20 VII Orange: acid dye, a ^* = 20 to 70, b ^* = 5
0-90 VIII red: reactive dye, a ^* = 40-70, b ^* = 2
0-60 IX green: acid dye, a ^* =-70 to -20, b ^*
= 50-90 3. The ink jet recording method according to claim 1, wherein the recording medium is a recording medium in which a vinyl chloride layer, a urethane or acrylic layer, and an ink receiving layer are laminated on a substrate in this order. 4. The ink jet recording method according to claim 1, wherein an overcoat layer is provided on the surface of the ink receiving layer on which the image has been formed. 5. The ink jet recording method according to claim 4, wherein a main component of the overcoat layer is a transparent acrylic resin. 6. The ink jet recording method according to claim 4, wherein an ultraviolet absorber is added to the overcoat layer. 7. A recorded matter formed by the inkjet recording method according to claim 1. Description: