JPH0971743A - Ink composition for ink jet and recording method therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a hot-melt ink compsn. for ink jet which gives a high-quality image excellent in adhesion to a recording medium. SOLUTION: This compsn., capable of forming recording dots when thermally liquefied and jetted onto a recording medium, at least contains 30-70wt.% fatty acid ester having an 18-36C alkyl group, 10-50wt.% dimer acid polyamide, and 0.5-5wt.% colorant. Recording dots formed from the compsn. on a recording medium are heated at 30-60 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet hot melt type ink composition and a recording method thereof.

[0002]

2. Description of the Related Art Conventionally, a water-soluble liquid ink composition has been widely used as an ink composition for ink jet recording. However, printing on paper where ink tends to soak causes "bleeding", and the recording medium is limited to processed paper. Overhead projector (OHP)
Even when recording on a sheet, a special treatment is required on the surface of the sheet because the drying property of the ink is poor. Therefore, as an ink composition that provides good print quality regardless of paper quality, a hot-melt type ink composition made of a solid wax at room temperature is used, liquefied by heating or the like, and added with some energy. A hot-melt type ink jet recording method has been proposed in which the ink is ejected and cooled and solidified while adhering onto a recording medium to form recording dots.

As a major advantage of the above-mentioned ink jet system, the ink is solid at room temperature so that it does not become dirty during handling, and the evaporation amount of the ink at the time of melting can be minimized so that the nozzle is not clogged. Further, since it solidifies immediately after being attached, there is no "bleeding", and various recording media such as Japanese paper, drawing paper, and postcards can be used without pretreatment.

[0004]

However, since the hot melt type ink contains wax as a main component, the penetration into the paper is restricted by the speed of solidification after adhesion, and the adhesion to the recording medium is poor and the image is bent. However, there was a problem that the ink peeled off from the recording medium when the recording medium was released, and sufficient recording and storage performance could not be obtained.

In the thermal transfer system, Japanese Unexamined Patent Publication No. 2-108592.
No. 6-74393, a polyamide resin is added to an ester wax having a penetration of 3 or less and high hardness, or a recording material using a polyamide composition having an increased adhesive force is disclosed. There is a method of applying. However, in the hot melt inkjet method, since the ink droplets are ejected from fine nozzles, the viscosity is 9
It is necessary to adjust the pressure to be lower than 50 mPa · s at 0 to 130 ° C., and it is necessary to select a wax having a low viscosity and excellent flow stability during melting.

In addition, since the nozzle base material and the ink are in contact with each other at a high temperature for a long time, it is absolutely necessary that the ink composition does not corrode. In addition, the ink can be ejected to an accurate position at all times. On the other hand, the fact that the composition is hard to wet, and that the ink has sufficient surface tension and cohesive force to prevent ink droplets from scattering while the ink arrives at the recording medium is only applicable to hot melt inkjet printers. It is a specific condition to be met.

On the other hand, in the hot-melt ink jet system, in order to improve the poor adhesion, a semicircular ink adhered to the surface of the recording medium is pressed by a roller from above and below to fix the ink on the recording medium. However, a wax having a penetration of 3 or less is not preferable because the hardness is too high and considerable pressure is required.

Further, in the production of a transparent film for OHP, etc., it is essential to flatten the ink dots in order to effectively obtain linearly transmitted light. One of the well-known means,
There is a pressure treatment method using a roller. At that time, since the secondary dots such as red, green, and blue overlap with the ink dots, the height of the ink dots is about twice that of the primary colors such as black, yellow, magenta, and cyan. Therefore, the pressure of the roller is not sufficiently applied to the primary color portion sandwiched between the secondary color regions, it is difficult to perform uniform processing, and a clear color OHP image cannot be obtained. Further, in order to increase the pressure applied to the ink dots, there is also a method of reducing the amount of ink per dot or thinning out the dots, but the saturation is lowered and it is difficult to obtain a vivid image.

Japanese Patent Application Laid-Open No. 2-69282 provides a phase change ink having a linear light transmission property by using a composition containing a monoamide and a tetraamide. These ink components have no resistance to a minute load and rubbing generated when carrying a double-sided printed catalog such as thick paper. Further, the melting point lowering phenomenon due to the reaction of the amide makes it difficult to obtain a desired melting point. Therefore, the material has a high melting point and a high melt viscosity, and
As a result, the load on the entire apparatus increases.

Further, in a recording medium in which ink does not easily penetrate, if the semicircular ink dots are left as they are, the sheets contact each other at the minimum area of the apexes of the dots when stacked.
Even wax having good abrasion resistance has a problem in that it is transferred (offset) to a non-recording portion or the like to be contaminated by rubbing with a minute force.

As described above, the hot-melt type ink jet recording system has many advantages as compared with the water-based type ink jet recording system, and thus is expected to be applied to OA equipment, general household printers, facsimiles and the like. But,
There are many problems as described above, and this has been a bottleneck for commercialization.

An object of the present invention is to provide an ink jet hot melt type ink capable of performing uniform and easy pressure fixing treatment with a roller or the like, excellent adhesion to a recording medium and good recording and storage performance, and a recording method thereof. To provide.

[0013]

SUMMARY OF THE INVENTION The gist of the present invention for solving the above problems is to form an ink jet hot melt capable of forming recording dots by heating and liquefying a solid ink and jetting it toward a recording recording medium. Type ink having at least (a) an alkyl group having 18 to 3 carbon atoms
30-70 weight percent of fatty acid ester of 6 (b)
A hot-melt ink composition for ink jet, which comprises 10 to 50 weight percent of a dimer acid-based polyamide (c) and 0.5 to 5 weight percent of a colorant, and a recording medium using the ink composition. The recording method of (3) heats the recording dots at 30 to 60 ° C.

The fatty acid ester is preferably a monohydric or polyhydric alcohol fatty acid ester. For example, sorbitan monopalmitate, sorbitan monostearate, sorbitan monobehenate, polyethylene glycol monostearate, polyethylene glycol distearate, propylene glycol monostearate, ethylene glycol distearate and the like are selected. In particular,
Reodol SP-S10, Reodol SP-S30, Reodol SA10, Emazole P-10, Emazole S
-10, Emazole S-20, Emazol B, Rheodol Super SP-S10, Emanone 3199, Emanone 3299, Exepearl PE-MS (Kao) and the like can be used. Even most preferred are fatty acid esters of glycerin. For example, stearic acid monoglyceride, palmitin monoglyceride, oleic acid monoglyceride, behenic acid monoglyceride and the like are selected. Specifically, Reodol MS-50, Reodol M
S-60, Reodol MS-165, Reodol MO-
60, Exepearl G-MB (Kao), deodorized purified carnauba wax No. 1. Purified candelilla wax No.
1 (Noda wax), Synchro wax ERL-C,
Synchro wax HR-C (Kuroda) and KF2 (Kawaken Fine Chemical) can be used. Exepearl DS-C2 (Kao) as a special ester wax,
Kawaslipu L and Kawaslipu R (Kawaken Fine Chemical) are also selected. Myrisyl serotinate, Seryl serotinate, Seryl montanate, Myricyl palmitate,
Higher alcohol esters of higher fatty acids such as myricyl stearate, cetyl palmitate and cetyl stearate are also selected. The alkyl groups here are present in both fatty acids and alcohols. At least one kind selected from these fatty acid esters, or a mixture of two or more kinds can be used.

This fatty acid ester has a low melt viscosity,
In addition to having stable fluidity when the ink is melted, it has high flexibility and strong surface protection as compared with carbon-carbon bonds, and therefore can withstand bending of printed images. Preferred fatty acid esters have a penetration of more than 1 and are easily pressurized. Further, those having a viscosity of less than 20 mPa · s during injection are suitable. The addition amount is preferably 30 to 70% by weight, and most preferably 40 to 60% by weight. When it is more than 70% by weight, the ink hardness is remarkably lowered, and the abrasion resistance of the recorded matter is lowered. On the other hand, if it is less than 30% by weight, the desired effect of the present invention cannot be obtained.

Polyamides are generally classified into aromatic polyamides and dimer acid polyamides. In the present invention, polyamides based on dimer (dimer) acid are particularly desirable. Optimally, the base acid is oleic, linoleic, linoleic or eleostearic acid. Specifically, Macromelt 6
030, Macromelt 6065, Macrom
elt 6071, Macromelt 6212, M
acromelt 6217, Macromelt 6
224, Macromelt 6228, Macrom
elt 238, Macromelt 6239, Ma
cromelt 6240, Macromelt 63
01, Macromelt 6900, DPX 80
2, DPX 830, DPX 850, DPX 925,
DPX 927, DPX 1160, DPX 116
3, DPX 1175, DPX 1196, DPX 1
358 (Henkel White Water), SYLVAMID E-5
(Arizona Chemical), UNIREZ 2224, UN
IREZ 2970 (Union Camp) and others are selected. These can be used at least one kind or as a mixture of two or more kinds.

All of these have good wettability to the recording medium and exhibit high adhesion performance. Further, it has excellent adhesion to a wide variety of adherend substances. It also has the function of further improving the excellent durability of the fatty acid ester. A preferred polyamide has a softening point of 90 ° C. or higher,
However, at a temperature higher than that, the composition must be such that a stable jet can be obtained. Addition amount is 10-50
Weight percent is preferred, most preferred is 10-3
0 weight percent. If it is more than 50 weight percent, the viscosity of the ink increases and ejection becomes difficult. If it is less than 10% by weight, the adhesiveness to the recording medium becomes insufficient and the storage performance deteriorates.

As the colorant, pigments and dyes which are soluble in the above-mentioned vehicle and have excellent thermal stability can be used without particular limitation, but soluble dyes (Solvent Dye) are particularly preferable. Any colorant can be used, so long as it is compatible with the other ink ingredients.

Specifically, there are the following.

<Cyan> MS Cyan HM-123
8, MS Cyan HSo-16, Cyan HSo
-144, MS Cyan VPG (Mitsui Toatsu), AI
ZEN SOT Blue-4 (Hodogaya Chemical), RES
OLIN BR. BlueBGLN 200%, MAC
ROLEX Blue RR, CERES BlueG
N, SIRIUS SUPRATURQ. Blue Z
-BGL, SIRIUS SUPRA TURQ. Bl
ue FB-LL 330% (Bayer Japan), KA
YASET Blue FR, KAYASET Blue
e N, KAYASET Blue 814, Tur
q. Blue GL-5 200, LightBlue
BGL-5 200 (Nippon Kayaku), DAIWA Bl
ue 7000, Oleosol Fast Blue
GL (Daiwa Kasei), DIARESIN Blue P
(Mitsubishi Kasei), SUDAN Blue 670, NEO
PEN Blue 808, ZAPON Blue 8
06 (BASF Japan).

<Yellow> MS Yellow HSm-
41, Yellow KX-7, Yellow EX-
27 (Mitsui Toatsu), AIZEN SOT Yellow
-1, AIZEN SOT Yellow W-3, AIZ
EN SOT Yellow-6 (Hodogaya Chemical), MA
CROLLEX Yellow 6G, MACROLEX
FLUOR. Yellow 10GN (Bayer Japan), KAYASET Yellow SF-G, K
AYASET Yellow2G, KAYASET Y
yellow AG, KAYASET Yellow
EG (Nippon Kayaku), DAIWA Yellow 33
0HB (Daiwa Kasei), HSY-68 (Mitsubishi Kasei), S
UDAN Yellow 146, NEOPEN Ye
low075 (BASF Japan), Oil Yel
low 129 (Central Synthetic Chemistry).

<Magenta> MS Magenta V
P, MS Magenta HM-1450, MS M
agenta HSo-147 (Mitsui Toatsu), AIZE
N SOT Red-1, AIZEN SOT Red
-2, AIZEN SOT Red-3, AIZEN
SOT Pink-1, SPIRON Red GEH
SPECIAL (Hodogaya Chemical), RESOLIN Re
d FB 200%, MACROLEX Red Vi
olet R, MACROLEX ROT 5B (Bayer Japan), KAYASET Red B, KAY
ASET Red130, KAYASET Red 8
02 (Nippon Kayaku), PHLOXIN, ROSE BEN
GAL, ACID Red (Daiwa Kasei), HSR-3
1, DIARESIN Red K (Mitsubishi Kasei), Oi
l Red (BASF Japan), Oil Pink3
30 (Central Synthetic Chemistry).

<Black> MS Black VPC
(Mitsui Toatsu), AIZEN SOTBlack-1, A
IZEN SOT Black-5 (Hodogaya Chemical), R
ESORIN Black GSN 200%, RES
OLIN Black BS (Bayer Japan), K
AYASET Black A-N (Nippon Kayaku), DA
IWA Black MSC (Daiwa Kasei), HSB-
202 (Mitsubishi Kasei), NEPTUNE Black X
60, NEOPEN Black X58 (BASF Japan), Oleosol Fast Black R
L (Taoka Chemical Industry) and the like. An appropriate amount of the colorant added is 0.5 to 5 weight percent of the ink. When it exceeds 5 weight percent, the offset becomes noticeable, and 0.
If it is less than 5% by weight, the image quality will deteriorate. Further, two or more kinds of colorants can be appropriately mixed and used for color adjustment and the like.

The hot melt ink for ink jet of the present invention contains the above-mentioned fatty acid ester, polyamide and colorant as essential components, and various resin components, surface treatment agents, and surfactants are added in order to further enhance the functionality of the composition. , A viscosity reducing agent, an antioxidant, a preservative, an ultraviolet absorber, a plasticizer and the like can be mixed.

The ink of the present invention meets several well-known requirements for application in hot melt ink jet printers. That is, the ink has sufficient hardness and stability at room temperature, and has high reliability in storage before printing and image quality after printing. After attaching to a recording medium, it has sufficient transparency and saturation, and forms a uniform thin film to give a printed matter of good image quality. These requirements are complicated and cannot be quantified clearly for the ink of the present invention, but for example, the melt viscosity at the time of printing is 50 mPa · s or less, especially 5
A range of up to 15 mPa · s is desirable for the device. Excessive viscosities require more energy at the time of injection, and materials with too low viscosities cause problems in storage stability at room temperature. The viscosity at room temperature (25 ° C.) is 10,000 mPa · s or more. The bending property of printed matter is 5 mm in the mandrel test using the transparency film.
It is desirable to pass the test of φ or less, especially 3 mmφ or less. In addition, it is necessary that offset does not occur even when printed matter is piled up even when stored at 40 ° C. The temperature at which the ink is melted during printing is optimally in the range of 100 to 150 ° C. in order to make the apparatus simple and inexpensive.
Therefore, it is desirable that the melting start temperature of the ink be 85 ° C. or lower and the glass transition temperature be 50 ° C. or lower. The surface tension during melting is desirably 30 mN / m. It is desirable that the volume change upon transition from the molten state to the solid be 10% or less.

There are no particular restrictions on the method of forming the inks of the respective colors, but it is desirable that the color tones of the dyes of the respective color inks have a complementary color relationship in subtractive color mixing. For example, when measured with an OHP sheet (transmitted light) with an ink thickness of 20 μm,
Saturation (C * ab) is 50 or more in yellow, preferably 10
0 or more, 50 or more for magenta, preferably 70 or more, and 30 or more for cyan, preferably 50 or more. The lightness (L *) of black is desirably 35 or less.

A heating roll treatment is suitable for the ink of the present invention, and this treatment is performed at the same time when the ink is transferred to a target recording medium after printing or after primary recording on another medium. In this case, the recording medium (paper, OHP sheet, etc.) that has been printed or has not yet been printed may be heated (preheated) before passing through the roll. This temperature is suitably 80 ° C. or less.

No excessive temperature is required as the roll heating temperature. For example, it is 30 to 60 ° C., and particularly 40 ° C. or lower. The roll pressure is 5 to 500 kgf / cm2
A wide range of is selected according to the purpose, but especially 10 to 5
0 kgf / cm2 is desirable. The material of the roll is polished stainless steel, metal such as nickel, polyethylene,
Many materials such as ultra-high-molecular-weight polyethylene, polyamides such as nylon, polyacetals such as Duracon, fluoropolymers such as Teflon, polymers having rubber properties such as polyurethane and chloroprene can be used. Rolls coated with molecules are preferred. If necessary, oil such as silicone oil can be applied to the roll to improve the characteristics.

Further, the composition provides a conventionally known ink jet printer that ejects ink droplets only when printing is required, such as the printer used in industrial marking, and all with this typical operation. It can be used for all types of printers. Examples of the recording medium include paper, plastic film, capsules, gels, metal sheets, and the like, but the recording medium is not limited thereto as long as non-contact printing is possible.

[0030]

In the present invention, since the hot-melt type ink has the composition containing the above-mentioned components, uniform and easy pressure-fixing treatment with a roller or the like is possible, a clear color is obtained, and the adhesion to the recording medium is improved. An object of the present invention is to provide an ink jet hot melt type ink having excellent recording storage performance and a recording method thereof.

[0031]

EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited to the described examples.

Table 1 shows the ink composition and color difference (ΔE * a
b), chroma (C * ab), adhesiveness, offset test results, melt viscosity, and Table 2 shows the composition material of the ink used and the manufacturer name, trade name, etc. In Table 2, M is magenta dye, C is cyan dye, Y is yellow dye, and Bk is black dye.

[0033]

[Table 1]

[0034]

[Table 2]

Example 1 As shown in Tables 1 and 2, fatty acid ester (Kawaken Fine Chemicals, trade name: Kawaslip-L) 56% by weight, polyamide (Henkel, trade name: Macromelt 6228) 30
Weight percent, petroleum resin (Arakawa Chemical, trade name: Alcon P-100) 10 weight percent, antioxidant (Yoshitomi Pharmaceutical, trade name: Yoshinox 2246G) 2 weight percent and cyan dye (BASF, trade name: N
A cyan hot melt ink was prepared by mixing 2 weight percent of EOPEN Blue 808). This mixture is heated and melted at 120 ± 10 ° C. for about 2 hours until a homogeneous molten mixture is obtained, followed by heat and pressure filtration to remove impurities and the like, and then allowed to cool at room temperature to obtain a homogeneous cyan hot melt ink. Got Similarly, instead of the cyan dye, a yellow dye (manufactured by Orient Chemical Co., Ltd., trade name: O
il Yellow 129), magenta dye (Chuo Synthetic Chemicals, trade name: Oil Pink 330), black dye (Taoka Chemical Industry, trade name: Oleosol F
As a result, four color hot melt inks were obtained.

An ink jet printer (manufactured by Hitachi Koki, model name: JOLT) is manufactured by using these four colors of hot melt ink.
Evaluation patterns were printed on various recording media by PSJ2).
After that, pressure fixing was performed with a fixing machine (manufactured by Hitachi Koki, model name: Transparency Enhancer).

First, in order to confirm whether or not uniform fixing is possible, an OHP transparent sheet (transparency film for JOLT) is provided with an evaluation pattern having different ink dot heights, that is, only primary colors (cyan / yellow / A pattern in which cyan) is adjacent to each other and a pattern in which a primary color (green / yellow / green) exists between secondary colors are printed. After processing with the above fixing device, the color difference between the yellow sandwiched between cyan and the yellow sandwiched between green (ΔE * a
The saturation (C * ab) of the yellow sandwiched between b) and cyan was measured. For measurement, Nippon Denshoku color difference meter (Sigma 90)
It was used. The color difference ΔE * ab between two object colors according to the L * a * b * color system is calculated by the following formula.

[0038]

[Equation 1]

Here, L * is a lightness index and a * b * is a chroma-takeness index.

Similarly, the saturation is

[0041]

[Equation 2]

It can be represented by

The criteria for judgment are shown as acceptable (◯) when ΔE * ab is 2.0 or less because the difference cannot be discerned by ordinary people, and as unacceptable (×) when the difference is more than that. C * a
Since b gives a vivid color image at 80 or more, it is shown as acceptable (◯) when it is 80 or more and not (x) when it is less than 80.

In order to check the recording and storage performance, first, in order to confirm the adhesiveness, a transparent sheet for OHP (JOLT) is used.
Transparency film) for printing. After fixing, the test piece was wound around a 1/8 inch mandrel and squeezed twice at room temperature to observe the degree of peeling of the ink film. ○ No peeling at all, × was observed even a little
It was expressed by.

Further, a test for confirming the presence or absence of offset was conducted. This is 55k, which is a standard copy sheet.
Two types of paper were used: g paper and thick 135 kg paper. After fixing, a standard copy paper is overlaid on the printed matter, 10 sets of each are prepared, one of them is bundled and the printed matter is shaken slightly, and then the ink bleeds on the printed matter and the ink is transferred on the overlaid copy paper surface. The inks were classified and evaluated by ink bleeding and ink without transfer (OK), and ink with ink bleeding and transfer (X).

The melt viscosity was measured with an E-type viscometer manufactured by Toki Sangyo. The average value measured five times at 130 ° C. and 100 rpm was defined as the melt viscosity.

The results are shown in Table 1 as in Example 1.
The one with ΔE * ab is 1.2 and the one with C * ab is 82.3.
Since a uniform fixing process could be performed, a clear image was obtained. As a result of the adhesion test, there was no peeling at all, and the offset test was acceptable (◯) for both 55 kg paper and 135 kg paper. Since the melt viscosity at 130 ° C. was as low as 13.0 mPa · s, stable injection could be performed.

Example 2 30% by weight of Kawaslip-L, 21% by weight of Macromelt 6228, 25% by weight of Alcon P-100,
Bisamide (Nippon Kasei, trade name: Thripax O) 2
0 weight percent, 2 weight percent Yoshinox 2246G, and NEOPEN Blue 8 respectively
08, Oil Yellow 129, Oil Pin
k330, Oleosol Fast Black R
L was added in an amount of 2% by weight, and four color hot melt inks were prepared in the same manner as in Example 1 (see Tables 1 and 2).

The results are shown in Table 1 as in Example 2.
The one with ΔE * ab is 1.0 and C * ab is 80.2,
Since a uniform fixing process could be performed, a clear image was obtained. As a result of the adhesion test, there was no peeling at all, and the offset test was acceptable (◯) for both 55 kg paper and 135 kg paper. Since the melt viscosity at 130 ° C. was as low as 10.0 mPa · s, stable injection could be performed.

Example 3 45% by weight of Kawaslip-L, 16% by weight of Macromelt 6228, 25% by weight of rosin ester (manufactured by Arakawa Chemical Co., Ltd., trade name: Pine Crystal K-100), plasticizer (manufactured by Kawaken Fine Chemicals, Product Name: PM-7200
T) 10 weight percent, 2 Yoshinox 2246G
Weight percent, plus NEOPEN Blu, respectively
e 808, Oil Yellow 129, Oil P
ink330, Oleosol Fast Black
2 weight percent of RL was added to prepare four color hot melt inks in the same manner as in Example 1 (Tables 1 and 2).
reference).

The results are shown in Table 1 as in Example 3.
The one with ΔE * ab is 0.8 and the one with C * ab is 81.5.
Since a uniform fixing process could be performed, a clear image was obtained. As a result of the adhesion test, there was no peeling at all, and the offset test was acceptable (◯) for both 55 kg paper and 135 kg paper. Since the melt viscosity at 130 ° C. was as low as 12.0 mPa · s, stable injection was possible.

Example 4 Fatty acid ester (made by Kuroda,
Product name: Syncrowax HR-C 70% by weight, polyamide (made by Henkel, product name: DPX-13
58) 10 weight percent, Alcon P-100 16
Weight percent, 2 weight percent Yoshinox 2246G, plus NEOPEN Blue 80
8, OilYellow 129, Oil Pink3
30, 2 Oleosol FastBlack RL
Weight percent was added to prepare four color hot melt inks in the same manner as in Example 1 (see Tables 1 and 2).

The results are shown in Table 1 as in Example 4.
The one with ΔE * ab is 0.9 and the one with C * ab is 82.5.
Since a uniform fixing process could be performed, a clear image was obtained. As a result of the adhesion test, there was no peeling at all, and the offset test was acceptable (◯) for both 55 kg paper and 135 kg paper. Since the melt viscosity at 130 ° C. was as low as 10.5 mPa · s, stable injection could be performed.

[Example 5] Syncrowax HR-C
30% by weight, DPX-1358 50% by weight, carnauba wax (Noda Wax, trade name: deodorized refined carnauba wax No. 1) 17.5% by weight, Yoshinox 2246G 2% by weight, and NEOPEN Blue 808, respectively.
Oil Yellow 129, Oil Pink 33
0, 0.5 weight percent of Oleosol Fast Black RL was added, and four color hot melt inks were prepared in the same manner as in Example 1 (see Tables 1 and 2).

The results are shown in Table 1 as in Example 5.
The one with ΔE * ab of 1.7 and C * ab of 80.1.
Since a uniform fixing process could be performed, a clear image was obtained. As a result of the adhesion test, there was no peeling at all, and the offset test was acceptable (◯) for both 55 kg paper and 135 kg paper. Since the melt viscosity at 130 ° C. was as low as 11.5 mPa · s, stable injection was possible.

Example 6 Syncrowax HR-C
62 weight percent, DPX-1358 33 weight percent, and NEOPEN Blue 8 respectively.
08, Oil Yellow 129, Oil Pin
k330, Oleosol Fast Black R
L was added in an amount of 5% by weight, and four color hot melt inks were prepared in the same manner as in Example 1 (see Tables 1 and 2).

The results are shown in Table 1 as in Example 6.
The one with ΔE * ab is 1.2 and the one with C * ab is 81.3.
Since a uniform fixing process could be performed, a clear image was obtained. As a result of the adhesion test, there was no peeling at all, and the offset test was acceptable (◯) for both 55 kg paper and 135 kg paper. Since the melt viscosity at 130 ° C. was as low as 10.2 mPa · s, stable injection could be performed.

Comparative Example 1 Deodorized refined carnauba wax N
o. 1 is 50 weight percent, fatty acid (Kawaken Fine Chemicals, trade name: F-3) is 48 weight percent, and NEOPEN Blue 808 and Oil respectively.
Yellow 129, Oil Pink 330, O
Two weight percent of leosol Fast Black RL was added, and four color hot melt inks were prepared in the same manner as in Example 1 (see Tables 1 and 2).

As is clear from Table 1, the characteristic evaluation results carried out in the same manner as in Example 1 show that ΔE * ab is 4.2 and C * ab is
Of 40.3, a uniform fixing process could not be performed, and thus the color was unclear. Also, the adhesion was poor and the image peeled off.

Comparative Example 2 51% by weight of F-3, 8% by weight of DPX-1358, Alcon P
-100 to 39 weight percent, plus NEO
PEN Blue 808, Oil Yellow 12
9, Oil Pink 330, Oleosol Fas
Add 2 weight percent of t Black RL, 4
Colored hot melt inks were prepared in the same manner as in Example 1 (see Tables 1 and 2).

As is clear from Table 1, the characteristic evaluation results carried out in the same manner as in Example 1 show that ΔE * ab is 6.5 and C * ab is
However, the color was unclear because the uniform fixing treatment could not be carried out. Also, the adhesion was poor and the image peeled off.

Comparative Example 3 60 weight percent Kawaslip-L, 18 weight percent Pine Crystal K-100, 20 weight percent PM-7200T, and NEOPEN Blue 808 and Oil respectively.
Yellow 129, Oil Pink 330, Ol
Example 2 of 4 hot melt inks with the addition of 2 weight percent of eosol Fast Black RL.
It adjusted by the operation similar to (refer Table 1-2).

As is clear from Table 1, the characteristic evaluation results carried out in the same manner as in Example 1 caused an offset.

[Comparative Example 4] Syncrowax HR-C
28 weight percent, DPX-1358 70 weight percent, and NEOPEN Blue 8 respectively.
08, Oil Yellow 129, Oil Pin
k330, Oleosol Fast Black R
L was added in an amount of 2% by weight, and four color hot melt inks were prepared in the same manner as in Example 1 (see Tables 1 and 2).

Since the melt viscosity was as high as 50.0 mPa · s, stable injection could not be performed.

[0066]

EFFECTS OF THE INVENTION The hot-melt ink for ink-jet of this embodiment can easily fix an image which has been a problem in the past, and therefore not only can obtain a clear color,
Furthermore, since the adhesion and offset can be greatly improved and improved, a high quality image can be obtained and the storage performance is improved.

Claims (3)

[Claims] 1. An ink composition for forming recording dots by liquefying an ink which is solid at room temperature by heating and ejecting the ink onto a recording medium, wherein at least (a) a fatty acid ester having 18 to 36 carbon atoms of an alkyl group is used. 30-70 weight percent (b) 10-% dimer acid based polyamide
A hot-melt ink composition for inkjet, comprising 50 to 50% by weight (c) of a colorant in an amount of 0.5 to 5% by weight. 2. In an ink jet printer for forming recording dots by liquefying a solid ink at room temperature by heating and ejecting it on a recording medium, at least (a) 30 fatty acid ester having 18 to 36 carbon atoms of an alkyl group is used. ~
70% by weight (b) 10 to 50% by weight of dimer acid based polyamide (c) 0.5 to 0.5% of colorant.
A recording method using an ink composition containing 5% by weight. 3. With respect to the recording dots on the recording medium, 30 to
The recording method according to the above-mentioned item 2, wherein heat treatment at 60 ° C. is performed.