JP3936581B2 - Inkjet printing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hot melt ink and an ink jet recording method using the hot melt ink, and more particularly, to a hot melt ink for ink jet printing for printing on a cloth or film as a recording medium, and an ink jet printing method using the same. About.
[0002]
[Prior art]
Conventionally, a recording method using ink jet printing has been widespread.
In this recording system, there is a method of recording an image by ejecting ink droplets onto a recording medium such as a cloth using a liquid ink obtained by dissolving a dye in a solvent such as water or an organic solvent.
However, this method has a problem that when these inks are printed on a recording medium, a bleeding phenomenon appears and a clear image cannot be obtained.
[0003]
In order to solve this point, for example, as disclosed in JP-A-61-138784, an ink jet printing method in which a receiving layer for receiving an ink liquid containing a disperse dye is previously formed on a recording medium. Is disclosed.
On the other hand, there is also a recording method in which an ink droplet is ejected onto a recording medium using a solid ink (hot melt ink) in which a pigment is contained in a solid substance at room temperature to print an image.
For example, as disclosed in Japanese Patent Application Laid-Open No. 07-278477, there is a method of performing inkjet printing using an ink containing a vehicle that melts and becomes liquid when heated to a melting point or higher at room temperature, for example, wax and a coloring material. In this way, a recording medium with relatively good fixability can be obtained without any penetration or spreading (bleeding) of the vehicle.
[0004]
[Problems to be solved by the invention]
However, in the case of ink jet printing using the former liquid type, although the texture and fastness are excellent, it is necessary to form an ink receiving layer on the recording medium in advance, and the load on the process is large.
Further, the latter solid-type ink jet printing is excellent in that it is not necessary to previously form an ink receiving layer on the recording medium, but since it contains a pigment or oil-based dye, the texture of the recording medium is inevitably increased. There was a drawback that it became hard and the friction fastness was low.
In particular, in the case of fiber fabrics and resin films, the texture and the fastness to friction are serious defects in quality, and an immediate solution has been desired.
[0005]
The present invention has been made against the background of the above technical problems.
That is, an object of the present invention is to provide a solid-type ink jet hot melt ink that eliminates the need for a pretreatment process for a recording medium, which is indispensable in conventional ink jet printing using liquid ink, and an ink jet printing method using the same. Is to provide.
It is another object of the present invention to provide a solid-type inkjet hot melt ink that has excellent friction resistance without impairing the texture of the recording medium, and has little deterioration in physical properties of the ink over time, and an inkjet printing method using the same. .
[0006]
[Means for Solving the Problems]
As a result of intensive studies, the present inventors have found that the above problems can be solved by using a hot-melt ink containing a water-soluble substance that is solid at room temperature, and have completed the present invention based on this finding.
[0007]
That is, the present invention is (1) an inkjet printing method using a hot melt ink, the hot melt ink comprising a dye and a water-soluble substance that is solid at room temperature and holds the dye in the ink. The present invention is an ink jet printing method in which an ink is applied to a recording medium by an ink jet method , and then a heat treatment and a cleaning process are performed on the recording medium .
[0008]
And (2) exists in the ink jet printing method of the said (1) description whose said water-soluble substance is a compound which has a polyethylene oxide group.
[0009]
In addition, (3) the ink jet printing method according to the above (1) or (2) , wherein the dye is a disperse dye.
[0010]
(4) Any of (1) to (3) above , wherein the melt viscosity of the hot melt ink is 1-1000 cps, the surface tension at the time of melting is 10-50 dyne / cm, and the melting point is 50-200 ° C. 1. The ink jet printing method according to item 1 .
[0012]
And ( 5 ) exists in the inkjet printing method of the said (1) description whose said recording medium is a fabric.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Since the present invention is a recording method using a hot melt ink containing a water-soluble substance that is solid at room temperature, the ink is easily solidified immediately after being applied to the recording medium, and the so-called “ No “bleeding” reduction occurs, and no pretreatment process is required.
Moreover, since the hot-melt ink uses a water-soluble substance, it usually does not remain on the recording medium when washed, and the texture of the recording medium is not impaired.
[0014]
In addition, since the ink jet printing method of the present invention dyes a dye onto a recording medium by a heat treatment after ink application, the recording medium after printing has excellent friction resistance.
In addition, since the hot melt ink of the present invention can dissolve or disperse a dye in a solid substance at room temperature, stable ink jet printing is possible with little deterioration in physical properties of the ink such as aggregation and sedimentation.
[0015]
As the dye used in the hot melt ink of the present invention, dyes used for normal dyeing such as direct dyes, acid dyes, reactive dyes, disperse dyes, vat dyes, sulfur dyes, naphthol dyes, basic dyes can be used. is there.
The above dye is appropriately selected depending on the type of fiber cloth or film as a recording medium.
When the recording medium is composed of two or more materials, it is preferable to use a combination of the dyes.
In the hot melt ink of the present invention, among these dyes, disperse dyes that are difficult to decompose even under high temperature conditions are preferable.
[0016]
The water-soluble substance of the hot melt ink of the present invention is a water-soluble substance that retains the dye in the ink, and is a solid and hot-melt substance that is solid at ordinary temperature (usually 10 ° C. to 45 ° C.).
Here, the melting point of the water-soluble substance is preferably 50 to 200 ° C., more preferably 50 to 100 ° C.
When the melting point of the ink is lower than 50 ° C., the recording medium is smeared, and there is a problem in handling such as stickiness.
When the ink melting point exceeds 200 ° C., the hot melt ink jet head also has a heat melting temperature setting exceeding 200 ° C., and the load on the ink jet printing apparatus increases.
[0017]
Specific examples of water-soluble substances include fatty acid glycerins, fatty acid sorbitans, fatty acid sucrose esters, polyalkylene oxides, polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene polyoxypropylene glycol Fatty acid polyethylene glycols, fatty acid polyoxyethylene sorbitans, fatty acid monocarboxylates, N-acyl sarcosine salts, N-acyl glutamates, dialkyl sulfosuccinates, alkane sulfonates, alpha olefin sulfonates, direct Chain alkylbenzene sulfonates, branched alkylbenzene sulfonates, alkylnaphthalene sulfonates, naphthalene sulfonic acid-formaldehyde condensates, alkyl sulfuric acid , Polyoxyethylene alkyl ether sulfates, oil and fat sulfate esters, alkyl phosphates, polyoxyethylene alkyl ether phosphates, polyoxyethylene alkylphenyl ether phosphates, polyethyleneimines, polyvinyl pyrrolidones, polyvinyl methyl ether , Carboxyvinyl polymers, sodium polyacrylates, polyvinyl alcohols or derivatives thereof.
[0018]
Of the above water-soluble substances, water-soluble substances having a polyethylene oxide group capable of dissolving dyes are more preferred.
Specifically, the dye dissolving power of the water-soluble substance is preferably such that 1 g or more of the dye can be dissolved in 100 g of the water-soluble substance.
That is, a preferable water-soluble substance is selected depending on the dye used.
As the ionicity of the water-soluble substance, either a nonion or an anion can be used.
As a method for producing the hot melt ink of the present invention, for example, the above water-soluble substance is heated to dissolve, mixed with pulverized dye as necessary to prepare a solution or dispersion, and then heated. There is a method of performing filtration using a filtration device or the like, pouring into a mold for molding, cooling to room temperature, and solidifying.
[0019]
Of course, additives such as surfactants, heat stabilizers, antioxidants, preservatives, pH adjusters, antifoaming agents, penetrants, and light resistance improvers can be added to the hot melt ink as necessary. is there.
Normally, the content of this additive is 0.1 weight from the viewpoint of compatibility at the time of ink preparation (because some water-insoluble materials make it difficult to dissolve or disperse in water-soluble solids). Preferably, about 10% to 10% by weight is employed.
[0020]
As the characteristics of the hot melt ink of the present invention, those having a melt viscosity of 1 to 1000 cps, a surface tension at the time of melting of 10 to 50 dyne / cm, and an ink melting point of 50 to 200 ° C., preferably 50 to 100 ° C. are preferable.
When the melt viscosity is in the above range, it is possible to stably eject fine ink droplets. When the surface tension at the time of melting is within the above range, it is possible to eject true spherical ink droplets without dot cracking. Is possible.
Further, when the melting point of the ink is in the above range, the load on the ink jet printing apparatus is reduced.
[0021]
The ink jet printing apparatus for melting the hot melt ink of the present invention and ejecting ink droplets is not particularly limited, but a head provided in a normal ink jet printer with a heating device added thereto, or a commercially available hot melt type Any inkjet recording apparatus may be used.
[0022]
Since the hot melt ink is solid at room temperature, it needs to be heated and liquefied in order to be ejected from the nozzle, and the heating use temperature is preferably about 50 to 200 ° C.
The recording medium to which ink is applied by ink jet ejection is colored by heat treatment.
As conditions for color development, for example, a heat treatment temperature of 100 to 200 ° C. and a time of about 0.5 to 30 minutes are employed.
As the heat treatment, for example, a dry heat treatment, a wet heat treatment, or the like is adopted, and naturally, an appropriate heating method is set depending on the target fiber.
The recording medium colored by the heat treatment is subjected to a washing treatment.
In the washing process, washing in a normal dyeing process is performed in accordance with the recording medium (resin film, fiber fabric, etc.).
[0023]
The resin film or fiber fabric that is a recording medium used in the present invention is not particularly limited as long as it can adsorb dye and develop color.
Examples thereof include polyester, acetate, nylon, acrylic, vinylon, polyvinyl chloride, polycarbonate, polypropylene, cellophane, celluloid, cotton, rayon, wool, silk and the like.
Among them, fiber fabrics such as knitted fabrics, woven fabrics and non-woven fabrics that have a fiber structure (three-dimensional structure) with a large surface area from the viewpoint of a large number of dyeing seats and a large ink holding power are more than smooth structures such as resin films. Among them, fiber fabrics that can be dyed with disperse dyes are particularly preferable.
Examples of the material of the fiber fabric that can be dyed with a disperse dye include polyester, acetate, nylon, acrylic, vinylon, and polyvinyl chloride.
[0024]
In the ink jet printing method of the present invention, a phenomenon such as bleeding does not occur even if pretreatment is not performed, but it is naturally possible to appropriately perform pretreatment as necessary.
Hereinafter, the present invention will be described with reference to examples.
In addition, this invention is not necessarily limited to the Example.
[0025]
【Example】
[Example 1]
97 parts by weight of polyethylene glycol # 1000 (polyalkylene oxides) as a water-soluble substance and 3 parts by weight of a disperse dye (CI DISPERSE RED 86) as a dye were prepared.
Then, they were heated and kneaded at a temperature of 150 ° C. until a homogeneous molten mixture was obtained, followed by heating and filtration to remove impurities, and left to cool at room temperature to obtain a homogeneous red hot melt ink.
[0026]
This ink was filled in an ink jet printer compatible with hot melt ink, and ink jet printing was performed on a polyester raised fabric prepared in advance under the following conditions.
Next, the above-mentioned napped fabric was subjected to heat treatment (wet heat 175 ° C. × 15 minutes) to develop a fixed color, and then washed.
In the ink jet printing, the ink temperature was 130 ° C., and the printing conditions were as follows.
[0027]
〔recoding media〕
Polyester napped fabric A piled yarn made of 180d polyester spun yarn and a double raschel fabric made of 100d polyester filament yarn were brushed, sheared and heat-set by ordinary processes to obtain a napped fabric.
[Printing conditions]
B) Nozzle diameter: 70 (μm)
B) Applied voltage: 50 (V)
C) Pulse width: 20 (μs)
D) Drive frequency: 1 (kHz)
E) Resolution: 360 (dpi)
[0028]
The image obtained by the above method was good with no blur immediately after printing and after color washing.
Further, the friction resistance was measured by using a friction tester type II (Gakushin type) according to the test method of JIS-L0849.
Furthermore, the texture after washing and drying was also good.
[0029]
[Example 2]
95 parts by weight of sorbitan stearate (fatty acid sorbitans) as a water-soluble substance, 3 parts by weight of a disperse dye (CI DISPERSE RED 86) as a dye, and polyoxyethylene (EO 15 mol) nonylphenyl ether (as a surfactant) 2 parts by weight of polyoxyethylene alkylphenyl ethers) was prepared.
Then, they are melt-mixed at a temperature of 150 ° C., and then the molten mixture is dispersed by passing three times under a heating type three roll mill at 80 ° C. under heating conditions, followed by heat filtration to remove impurities, The mixture was allowed to cool at room temperature to obtain a homogeneous red hot melt ink.
[0030]
In the same manner as in Example 1, this ink was printed on a polyester raised fabric, fixed color was developed by heat treatment, and finally washed.
The image obtained by the above-described method was good without blurring immediately after printing and after color washing.
In addition, the friction resistance was measured by using a friction tester type II (Gakushin type) according to the test method of JIS-L0849.
Furthermore, the texture after washing and drying was also good.
[0031]
[Example 3]
Printing was carried out under the same conditions as in Example 1 except that a normal 100% polyester flat woven fabric (150d for both warp and weft) was used instead of the raised fabric.
The image obtained by the above-described method was good without blurring immediately after printing and after color washing.
Moreover, as a result of measuring the friction resistance using a friction tester type II (Gakushin type) by the test method of JIS-L0849, it was as good as 3-4 grade.
Furthermore, the texture after washing and drying was also good.
[0032]
[Example 4]
97 parts by weight of polyoxyethylene (EO 20 mol) cetyl ether (polyoxyethylene alkyl ethers) as a water-soluble substance and 3 parts by weight of a disperse dye (CI DISPERSE BLUE 77) as a dye were prepared. A homogeneous blue hot melt ink was obtained in the same procedure.
Using this ink, an ink jet printer compatible with hot melt ink similar to that in Example 1 was filled, and the above ink was printed on a polyester napped fabric under the condition of an ink temperature of 130 ° C.
The image obtained by the above-described method was good without blurring immediately after printing and after color washing.
In addition, the friction resistance was measured by using a friction tester type II (Gakushin type) according to the test method of JIS-L0849.
Furthermore, the texture after washing and drying was also good.
[0033]
[Example 5]
97 parts by weight of polyethylene glycol # 1000 (polyalkylene oxides) as a water-soluble substance and 3 parts by weight of an acid dye (CI ACID RED 249) as a dye were prepared.
Then, they were heated and kneaded at a temperature of 150 ° C. until a homogeneous molten mixture was obtained, followed by heating and filtration to remove impurities, and left to cool at room temperature to obtain a homogeneous red hot melt ink.
[0034]
Using the same printer as in Example 1, the ink was printed on a normal 100% nylon 100% plain woven fabric (150d for both warp and weft).
The ink temperature was 130 ° C., and the printing conditions were as in Example 1.
Next, the above flat woven fabric was fixed and colored by heat treatment (wet heat 105 ° C. × 15 minutes), and finally washed.
The image obtained by the above-described method was good with no blur immediately after printing and after color development washing.
Further, the friction resistance was measured by using a friction tester type II (Gakushin type) according to the test method of JIS-L0849.
Furthermore, the texture after washing and drying was also good.
[0035]
[Example 6]
Printing was performed under the same conditions using the same ink as in Example 1 except that a polyester film having a thickness of 50 μm was used.
Next, fixation color development was performed by heat treatment (dry heat 200 ° C. × 1 minute), and finally washing was performed.
The image obtained by the above-described method was good with no blur immediately after printing and after color development washing.
Further, the friction resistance was measured by using a friction tester type II (Gakushin type) according to the test method of JIS-L0849.
Furthermore, the touch after washing and drying was also good.
[0036]
[Comparative Example 1]
(Equivalent to ink-jet printing by liquid type that forms an ink receiving layer)
A pretreatment liquid prepared according to the following formulation was applied to a fabric similar to the fabric used in Example 1 by the mangle pad method and dried with hot air at 100 ° C. to form an ink receiving layer.
[0037]
Pretreatment prescription fine gum SP-1 [Daiichi Kogyo Seiyaku Co., Ltd.] 2 parts by weight (carboxymethylcellulose)
Reactant MS [Reduction inhibitor] 1 part by weight Water 97 parts by weight Next, an aqueous disperse dye ink was prepared as follows, and the pretreated polyester napped fabric was subjected to the following on-demand type serial scanning ink jet printing apparatus. The printing was performed under the following printing conditions.
Next, the above-mentioned raised fabric was subjected to heat treatment (wet heat at 175 ° C. for 15 minutes) in the same manner as in Example 1 to develop a fixed color, and then washed.
[0038]
Ink formulation disperse dye (CI DISPERSE RED 86) 3 parts by weight lignin sulfonate (anionic surfactant) 4 parts by weight Shin-Etsu Silicone KM-70 (antifoaming agent) 0.05 parts by weight ethylene glycol 10 parts by weight Kei Acid 0.1 parts by weight Deionized water 80 parts by weight [0039]
Printing conditions Nozzle diameter: 50 μm
Drive voltage: 100V
Frequency: 5000Hz
Resolution: 360 dpi
The obtained image was a good image with no blur and the friction resistance was as good as 4th grade.
The texture after washing and drying was also good.
However, since a pre-treatment process (ink-receiving layer formation) of the fabric is required, an extra processing man-hour is added, the processing time is long, and the cost is higher than that of the present invention.
[0040]
[Comparative Example 2]
(Equivalent to inkjet printing with solid ink that contains pigment in solid water-insoluble substance at room temperature)
100 parts by weight of Hi-Mic-1070 (wax, Nippon Seiwa Co., Ltd.) was collected as a water-insoluble substance, melted at 130 ° C., and 1 part by weight of HOSTAPERM PIN E-02 (Clariant Co.) as a pigment. , And 0.3 parts by weight of LANOX FP-1410N (dispersing agent, Nippon Seika Co., Ltd.), dispersed using a heat-compatible disperser, then filtered by heating to remove impurities, and allowed to cool at room temperature A homogeneous magenta hot melt ink was then prepared.
The hot melt ink composed of the wax and the pigment is filled in the same inkjet printer compatible with the hot melt ink as in Example 1, and the ink is printed on the same polyester raised fabric as in Example 1 under the condition of an ink temperature of 130 ° C. I did a copy.
[0041]
The obtained image was a good image with no blurring, but showed a first grade in friction resistance, and the ink peeling phenomenon was clearly confirmed in the image after the friction resistance test.
Moreover, the texture was hard and the flexibility of the fabric was impaired.
In addition to the above, a physical property deterioration experiment was conducted in order to see the physical property deterioration of the ink over time.
In the physical property deterioration experiment, a test tube containing 10 ml of ink was allowed to stand at room temperature for a certain period (10 days, 20 days, 30 days), and a precipitate was observed.
The results of Examples 1, 2, 4, 5 and Comparative Examples 1 and 2 are shown in Table 1.
[0042]
【The invention's effect】
Since the hot melt ink of the present invention and the ink jet printing method using the same use a dye and a water-soluble substance that is solid at room temperature, the dye can be fixed to a recording medium by heat treatment, and it is water-soluble. The material can be easily removed by washing.
Therefore, it is possible to obtain a recording medium having a good texture and high friction fastness while maintaining the advantage of the hot melt ink that pretreatment is not necessary.
The present invention can be applied not only to fiber fabrics but also to resin films and the like, and is particularly effective for fabrics for industrial materials such as clothing and car seats where friction resistance is important. Ink and inkjet printing methods.
[0043]
[Table 1]

Claims (5)

  An ink jet printing method using a hot melt ink, wherein the hot melt ink is composed of a dye and a water-soluble substance that is solid at room temperature to hold the dye in the ink, and the hot melt ink is applied to a recording medium by an ink jet method. Thereafter, a heat treatment and a cleaning treatment are performed on the recording medium. 2. The ink jet printing method according to claim 1, wherein the water-soluble substance is a compound having a polyethylene oxide group. The inkjet printing method according to claim 1, wherein the dye is a disperse dye. The melt viscosity of the hot melt ink is 1 to 1000 cps, the surface tension at the time of melting is 10 to 50 dyne / cm, and the melting point is 50 to 200 ° C. Inkjet printing method . Inkjet Shirushiutsushi method of claim 1, wherein said recording medium is a fabric.