JPH10310728A - Ink composition for ink-jet and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition excellent in adhesivity and weatherability, by including a polyamide from which a component meltable in an alkyl alcohol is removed. SOLUTION: This composition is obtained by adding a polyamide (e.g. dimer acid polyamide) from which a component (e.g. an analog compound having a molecular weight smaller than that of the main body of the polyamide) meltable in an alkyl alcohol [e.g. isopropanol (IPA)] to an amide group-containing vehicle [e.g. fatty acid amide (e.g. oleic acid amide) or a fatty acid ester (e.g. stearic acid monoglyceride)]. For example, the removal of a low molecular- weight component liable to cause a reaction to light and heat is recognized after washing by the result of GPC using a low molecular column before and after washing with IPA of DPX335-10. The amount of the polyamide added is preferably 10-40 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot-melt ink composition used in, for example, an ink jet recording apparatus and a method for producing the same.

[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. Also, an overhead projector (hereinafter OH)
Even when recording on a sheet (hereinafter referred to as P), a special treatment is required for the sheet surface because the drying property of the ink is poor. For this reason,
As an ink composition that provides good printing quality irrespective of paper quality, using a hot melt type ink composition made of a solid wax or the like at room temperature, liquefied by heating or the like, added with some energy, and ejected, There has been proposed a hot-melt ink-jet recording method in which a recording dot is formed by cooling and solidifying while adhering on a recording medium.

A major advantage of the above-mentioned ink jet system is that the ink is solid at room temperature and does not stain during handling, and the amount of evaporation of the ink during melting can be minimized, so that nozzle clogging does not occur. Can be Another advantage is that various types of recording media such as Japanese paper, drawing paper, and postcards can be used without pretreatment, because they solidify immediately after adhesion.

[0004] US Patent Nos. 4,390,369 and 4,484,948 describe ink compositions that provide good print quality regardless of paper quality.

[0005]

However, since the hot-melt ink contains wax as a main component, its penetration into paper is limited by the speed of solidification after adhesion, and the image is bent due to poor adhesion to the recording medium. However, there were problems such as the ink being peeled off from the recording medium at the time of recording and the heat and light stability being poor due to the large polarity, and sufficient recording storage performance and weather resistance could not be obtained.

The thermal transfer method is disclosed in Japanese Patent Application Laid-Open No. 2-108592.
JP-A-6-74393 discloses that a polyamide resin is added to an ester wax having a penetration of 3 or less and having high hardness. It is disclosed that the adhesiveness is improved by a method of applying an adhesive.

However, in the ink jet system using hot melt type ink, since the ink droplets are ejected from fine nozzles, the viscosity of the ink is 90 to 130 ° C. and the viscosity is 50 ° C.
It is necessary to adjust the viscosity to be lower than mPa · s, and an ink composition having a low viscosity and excellent flow stability at the time of melting is required. In addition, since the nozzle base material and the ink come into contact with each other at high temperature for a long period of time, the absolute condition is that the ink composition is resistant to heat.In addition, the ink must always be ejected to the correct position on the nozzle surface. The composition is hard to wet,
In addition, the ink composition applied to a hot-melt inkjet printer requires specific conditions, such as an ink with sufficient surface tension and cohesion to prevent ink droplets from scattering while the ink arrives on the recording medium. And

Japanese Patent Application Laid-Open No. 2-206661 discloses that an antioxidant is added in order to improve the heat resistance of a hot melt ink. However, it was necessary to study the compatibility of the additive with the main component, that is, the material and the amount that can be added without changing the characteristics of the ink.

In Japanese Patent No. 2525710, the specific dye is treated with an amine to stabilize the saturation and lightness of the ink.

As described above, the ink jet recording method using the hot melt type ink has many advantages as compared with the aqueous type ink jet recording method, so that it is expected to be applied to OA equipment, general home printers, facsimile machines and the like. . However, there are many problems as described above, and this has been a bottleneck for commercialization.

The present invention has been made to solve the above-mentioned problems, and has as its object to provide excellent adhesion to a recording medium, good recording storage performance, and weather resistance (a property capable of withstanding the influence of heat and light). An object of the present invention is to provide an excellent hot-melt ink for ink jet, which does not require an additive to the ink.

[0012]

An object of the present invention is to provide an ink jet printing type ink composition which forms a recording dot by liquefying a solid ink at a room temperature by heating and jetting it onto a recording medium to form a vehicle having an amide group. Can be achieved by providing an ink composition containing a polyamide from which components that melt in the alkyl alcohol have been removed.

Preferably, the molten component is a similar compound having a lower molecular weight than the polyamide itself, and the polyamide from which the molten component has been removed has a melting point of 90 ° C. or more and 130 ° C. or less.

More preferably, the vehicle contains a polyamide having an amine value of at least 1 and not more than 8 but not less than 10% by weight and not more than 40% by weight, and 0.5 to 5% by weight of a coloring agent having good stability with the vehicle. It is preferable that the ink composition contains not more than a percentage.

The above ink composition comprises a step of dipping the polyamide in an alkyl alcohol, removing a molten component by filtration, drying the polyamide on the filter paper, and a step of drying the polyamide obtained in the step and other polyamide. It is produced by a process of mixing vehicle components.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described specifically, but is not limited to the described examples.

First, as the vehicle material, specifically, petroleum wax such as paraffin wax and microcrystalline wax, candelilla wax, vegetable wax represented by carnauba wax, polyethylene wax, hardened castor oil, stearic acid, behen Higher fatty acids such as acids and ketones such as higher alcohols, stearones and laurons, particularly fatty acid ester amides, saturated or unsaturated fatty acid amides and fatty acid esters are desirable.

The fatty acid ester amide is CPH-380.
N is chosen.

Fatty amides have a low melt viscosity at around 100 ° C., and have remarkable effects of lowering the melting point of the ink and lowering the viscosity during melting. In addition to being stable in fluidity when the ink is melted, it is a component that is useful for hot-melt inks because it has strength enough to withstand rubbing or bending of printed images.

Examples of the fatty acid amide include N-substituted fatty acids such as lauric amide, stearic amide, oleic amide, erucamide, ricinoleamide, stearic ester amide, palmitic amide, behenic amide, and brassic amide. As an amide, N,
N'-2-hydroxystearic acid amide, N, N'-ethylenebisoleic acid amide, N, N'-xylenebisstearic acid amide, stearic acid monomethylolamide, N-oleylstearic acid amide, N-stearylstearic acid Amide, N-oleyl palmitic acid amide, N-stearyl erucic acid amide, N, N'-dioleyl adipamide, N, N'-dioleyl sebacic amide, N, N'-distearyl isophthalic amide, 2 -Stearamide ethyl stearate and the like are selected.

Fatty acid esters have low melt viscosity and stable fluidity at the time of ink melting, and also have high flexibility and high surface protection compared to carbon-carbon bonding, so that printed images are bent. There is also a property that can withstand. Preferred fatty acid esters have a penetration of more than 1 and are easily pressurized. Further, those having a viscosity at the time of ink ejection of less than 20 mPa · s are suitable.

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 more preferred are fatty acid esters of glycerin. For example, stearic acid monoglyceride, palmitic 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 added amount of these vehicle materials is 3
0 to 90 weight percent is preferred, most preferably 40 to 60 weight percent. If the content is more than 90% by weight, the durability of the recorded matter is reduced. On the other hand, if the amount is less than 30% by weight, the fluidity at the time of melting the ink becomes unstable, and the print quality deteriorates.
In such a case, for example, a high molecular weight resin such as a rosin resin, an acrylic resin, a hydrocarbon resin, or a polyamide resin can be added. As the vehicle, at least one kind selected from these, or a mixture of two or more kinds can be used.

Polyamides are generally classified into aromatic polyamides and dimer acid polyamides. In the present invention, polyamides based on dimer (dimer) acids are particularly desirable. Optimally, the base acid is oleic, linoleic, linoleic or eleostearic acid. Specifically, Macromelt 6030, Macrom
elt 6065, Macromelt 6071, Macromelt 6212, Macromel
t 6217, Macromelt 6224, Macromelt 6228, Macromelt
238, Macromelt 6239, Macromelt 6240, Macromelt 630
1, Macromelt 6900, DPX 335-10, DPX H-415, DPX 33
5-11, DPX 830, DPX 850, DPX 925, DPX 927, DPX 116
0, DPX 1163, DPX 1175, DPX 1196, DPX 1358 (Henkel Hakusui), SYLVAMID E-5 (Arizona Chemical), UNIRE
Z 2224, UNIREZ 2970 (union camp), etc. are selected.

The amount of polyamide added to the vehicle is 10
~ 40 weight percent is preferred. If it is less than 10% by weight, not only will the color change be insignificant, but also
The adhesion to the recording medium is insufficient and the storage performance is poor.
If the content is more than 40% by weight, the viscosity of the ink increases, and the ejection becomes difficult.

The above polyamides can be used in combination of at least one kind selected from these or two or more kinds. All of these have good wettability to a recording medium and exhibit high adhesive performance. Furthermore, it has excellent adhesion to a wide variety of adherend substances.

It is desirable that the polyamide be sufficiently melted in the alkyl alcohol, filtered and dried before use. As the alkyl alcohol to be used, 1-alkanol and 2-alkanol are preferable.
Examples thereof include -hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, and 2-octanol, with 2-propanol (isopropanol; hereinafter, referred to as IPA) being particularly preferred.

FIG. 1 shows a gel permeation chromatogram (GPC) of DPX335-10 using a low-molecular-weight column before and after IPA washing. This figure is normalized by the peak of the arrow.

There is no significant change in the peak corresponding to a relatively high molecular weight in which the retention time in the column is short, but the latter peak, that is, the peak indicating a low molecular weight and a long retention time in the column, shows an intensity of DPX335-10 after washing. Is getting weaker. As described above, the effects of the present invention can be obtained by removing components which easily react to low molecular weight light and heat without losing the advantage of the ink composition as a high molecular weight component.

Further, the softening point of the polyamide is 90 ° C. or higher.
It is desirable that the melt viscosity at the temperature is 10 or more and 380 mPa.s or less. Therefore, FIG.
Temperature characteristics are shown. If it is less than 10 mPa · s, the crystallinity is so high that flexibility cannot be imparted to the ink. Above 380 mPa · s, the viscosity of the ink increases. As described above, polyamide has a characteristic that a required viscosity can be obtained with respect to the temperature at the time of ink ejection.

FIG. 3 shows the relationship between the amount of polyamide added and the color change from the initial color (ΔE * ab light). An ink composition prepared by adding a polyamide (manufactured by Henkel, trade name: DPX335-11) to a fatty acid amide (manufactured by Kao, trade name: fatty acid amide ON) was used. Goal is △ E * ab 5
In the following, this value is determined because the difference cannot be recognized by ordinary people when ΔE * ab is 5 or less. Details will be described later. In particular, DPX 335-10 and DPX 335-11 had excellent properties.

As the coloring agent, pigments and dyes which are dissolved in the above-mentioned vehicle and have excellent heat stability can be used without any particular limitation, and oil-soluble dyes are particularly desirable. In particular, the effect of the present invention is remarkable in a magenta dye classified as Solvent Red 49 in a color index such as Oil Pink 330 (Chuo Gosei Kagaku). Any colorant can be used as long as it is compatible with other ink components.

Specific examples of the coloring agent include the following. <Cyan> MS Cyan HM-1238, MS Cyan HSo-16, Cyan
HSo-144, MS Cyan VPG (Mitsui Toatsu), AIZEN SOT Blue
-4 (Hodogaya Chemical), RESOLIN BR.Blue BGLN 200%, MACR
OLEX Blue RR, CERES BlueGN, SIRIUS SUPRATURQ.Blue
Z-BGL, SIRIUSSUPRA TURQ.Blue FB-LL330% (Bayer Japan), KAYASET Blue FR, KAYASETBlue N, KAYASE
T Blue 814, Turq.Blue GL-5 200, LightBlue BGL-5
200 (Nippon Kayaku), DAIWA Blue 7000, Oleosol Fast Blu
e GL (Daiwa Kasei), DIARESINBlue P (Mitsubishi Kasei), SU
DAN Blue 670, NEOPEN Blue 808, ZAPON Blue 806 (B
ASF Japan), COLORTEX Blue A818, COLORTEX Blu
e # 516 (Sanyo dye). <Yellow> MS Yellow HSm-41, Yellow KX-7, Yello
w EX-27 (Mitsui Toatsu), AIZEN SOT Yellow-1, AIZEN S
OT YelloW-3, AIZEN SOT Yellow-6 (Hodogaya Chemical), M
ACROLEX Yellow 6G, MACROLEX FLUOR.Yellow 10GN (Bayer Japan), KAYASET Yellow SF-G, KAYASET Ye
llow2G, KAYASET Yellow A-G, KAYASETYellow E-G
(Nippon Kayaku), DAIWA Yellow 330HB (Daiwa Kasei), HS
Y-68 (Mitsubishi Kasei), SUDAN Yellow 146, NEOPEN Yellow
075 (BASF Japan), Oil Yellow 129 (Orient Chemical), COLORTEX Yellow # 301, COLORTEX Yellow
# 316 (Sanyo dye). <Magenta> MS Magenta VP, MS Magenta HM-1450, MS
Magenta HSo-147 (Mitsui Toatsu), AIZEN SOT Red-1, A
IZEN SOT Red-2, AIZEN SOT Red-3, AIZENSOT Pink-
1. SPIRON Red GEHSPECIAL (Hodogaya Chemical), RESOLIN Re
d FB 200%, MACROLEX Red Violet R, MACROLEX ROT 5B
(Bayer Japan), KAYASET Red B, KAYASET Red 1
30, KAYASET Red 802 (Nippon Kayaku), PHLOXIN, ROSE BEN
GAL, ACID Red (Daiwa Chemical), HSR-31, DIARESIN Red
K (Mitsubishi Kasei), Oil Red (BASF Japan), COLOR
TEX Red # 105, COLORTEX Red # 102 (Sanyo dye). <Black> Nigrosine Base EX (Orient Chemical), M
S Black VPC (Mitsui Toatsu), AIZEN SOT Black-1, AIZEN
SOT Black-5 (Hodogaya Chemical), RESORIN Black GSN 200
%, RESOLIN Black BS (Bayer Japan), KAYASET
Black A-N (Nippon Kayaku), DAIWA Black MSC (Daiwa Kasei), HSB-202 (Mitsubishi Kasei), NEPTUNEBlack X60, NEOP
EN Black X58 (BASF Japan), Oleosol Fast Bla
ck RL (Taoka Chemical Industry), Chuo Black 80 (Chuo Gosei Kagaku), COLORTEX Black # 702 (Sanyo Dye).

An appropriate amount of the coloring agent is 0.5 to 5% by weight of the ink. If it exceeds 5% by weight, the offset becomes conspicuous, and if it is less than 0.5% by weight, the image quality deteriorates. In addition, two or more kinds of colorants can be appropriately mixed and used for color adjustment or the like.

In addition to the above, the ink-jet ink composition of the present invention exhibits further functionality to the composition.
Various resin components, surface treatment agents, surfactants, viscosity reducing agents, preservatives, plasticizers, and the like can be mixed.

The preparation of high quality inkjet inks requires a balance of many important factors. The ink of the present invention satisfies several well-known requirements for application to hot melt inkjet 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. While these requirements are complex and cannot always be clearly quantified for the inks of the present invention, for example, hot melt inks with relatively low melting points are typically susceptible to bleed and offset. Even when stored at 40 ° C., it is necessary that offset does not occur in a state where printed matters are stacked. However, the higher the melting point of the ink, the higher the viscosity,
The melt viscosity at the time of printing is 50 mPa · s or less, especially 5 to 1
A range of 5 mPa · s is desirable on the apparatus. Excessive viscosity requires more energy at the time of injection, and a material having too low viscosity causes a problem in storage stability at room temperature. The viscosity at room temperature (25 ° C.) is 10,000 mPa · s or more.

For many inks, the viscosity can be reduced to a range suitable for ejection by increasing the ejection temperature.
Increasing the ejection temperature causes thermal stability problems, and heating for a long time in an ink reservoir (ink chamber) or print head may decompose the ink or corrode a metal material in contact with the ink.

The bending property of the printed matter was 5 in a mandrel test using a transparency film.
It is desirable to pass the test of not more than mmφ, especially not more than 3 mmφ. 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, the melting start temperature of the ink is 80
C. or lower, and the glass transition temperature is preferably 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.

Although there is no particular limitation on the method of forming each color ink, it is preferable that the color tones of the colorants of each color ink have a complementary color relationship by subtractive color mixing. For example, when measured with an OHP sheet (transmitted light) having an ink thickness of 20 μm, the chroma (C * ab) is 50 or more for yellow, preferably 100 or more, 50 or more for magenta, preferably 70 or more, and 30 or more for cyan. Desirably, it is 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 as when the ink is transferred to a target recording medium after printing or after primary recording on another medium. In this case, the printed or unprinted recording medium (paper, OHP sheet, etc.) may be heated (preheated) before passing through the roll. This temperature is suitably 80 ° C. or less. No excessive temperature is required for the roll heating temperature. For example, it is 30 to 60 ° C., particularly 40 ° C. or less. As the pressure of the roll, a wide range of 5 to 500 kgf / cm ² is selected according to the purpose.
kgf / cm ² is desirable. Rolls are made of polished metals such as stainless steel and nickel, polyethylene, ultra-high molecular weight polyethylene, polyamides such as nylon, polyacetals such as Duracon, fluoropolymers such as PTFE, and polymers having rubber properties such as polyurethane and chloroprene. Many materials can be used, such as a roll coated with a polymer exhibiting rubber elasticity. If necessary, oil such as silicone oil can be applied to the roll to improve the characteristics.

In addition, the composition can be used in ink jet printers known in the art to eject ink droplets only when printing is required, such as printers used for industrial marking, and all types of printers having this typical operation. Can be used for printers.

Examples of the recording medium include paper, plastic films, capsules, gels, metal sheets, and the like, but are not limited thereto as long as non-contact printing is possible.

Next, the present invention will be described with reference to specific examples.

Table 1 shows the results of the ink composition, adhesion, offset test, melt viscosity, heat resistance, and light resistance.
Table 2 shows the ink composition materials used and the manufacturer names,
Table 3 shows the amine value of the polyamide used,
Shows melt viscosity and softening point or melting point. In Table 2, M is a magenta colorant, C is a cyan colorant, Y is a yellow colorant, and Bk is a black colorant.

[0046]

[Table 1]

[0047]

[Table 2]

[0048]

[Table 3]

Example 1 First, 200 parts by weight of IPA was added to 20 parts by weight of a polyamide (manufactured by Henkel, trade name: DPX335-11). Then, after a while, in order to remove the molten component, the mixture is filtered with a 10-micrometer PTFE membrane filter (manufactured by Advantech Toyo). Next, the polyamide on the filter paper was taken in a petri dish and dried in an oven at 40 ° C.

10% by weight of the obtained DPX335-11 and 48% by weight of fatty acid amide (manufactured by Kao, trade name: fatty acid amide ON) and carnauba wax (manufactured by Noda Wax, as shown in Tables 1 and 2) Name: 40% by weight of deodorized purified carnauba wax No. 1) and cyan dye (manufactured by BASF, trade name: NEOPEN Blu)
e808) A cyan hot melt ink composition was prepared by mixing 2 weight percent.

This mixture is heated and melted at 120 ± 10 ° C. for about 2 hours until a homogeneous molten mixture is obtained, followed by filtration under heating and pressure to remove impurities and the like, and then cooled at room temperature to obtain a homogeneous cyanide. A hot melt ink was obtained.

Similarly, instead of the cyan dye, a yellow dye (manufactured by Orient Chemical Co., trade name: OilYellow 129) and a magenta dye (manufactured by Chuo Gosei Chemical Co., trade name: Oil Pink33)
0), black dye (manufactured by Taoka Chemical Industry, trade name: Oleosol)
By using Fast Black RL), hot melt inks of four colors were obtained.

An ink jet printer (manufactured by Hitachi Koki, model name: JOLT PSJ) using these four-color hot melt inks
In 2), the evaluation patterns were printed on various recording media. Also,
The record keeping performance was examined by the following method.

Printing was performed on a transparent sheet for OHP (transparency film for JOLT) to confirm the adhesion. After fixing, the test piece was wound around a mandrel (cylindrical bar) having a diameter of 10, 8, 6, 4, or 2 inches, and squeezed twice at room temperature to indicate the diameter at which the ink film peeled off. 10 indicates that the adhesion is the worst. In addition, those with no peeling were regarded as nothing.

Further, a test for confirming the presence or absence of an offset was performed. This includes 55kg, a common copy paper
Two types of paper, paper and thick 135 kg paper, were used. After fixing, a general copy paper is overlaid on the printed matter, ten sets of each are prepared, and one of them is bundled, and the printed matter is slightly shaken. Then, the ink bleeds on the printed matter, and the ink is transferred on the overlapped copy paper surface. Was evaluated, and the ink was smeared, and the presence or absence of transfer was evaluated.

The melt viscosity was measured using 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 heat resistance is as follows.
After storage for days, the color change from the initial color (ΔE * ab (heat)) was evaluated.

The light resistance was measured by printing the print sample for 6 hours with Xe.
Exposure to a lamp, color change from initial color as well as heat resistance (△
E * ab (light)). The target is ΔE * ab ≦ 5 for both heat resistance and light resistance.

The measurement was performed using a color difference meter (Sigma 9) manufactured by Nippon Denshoku.
0) was used. The color difference ΔE * ab between two object colors in the L * a * b * color system is obtained by the following equation.

[0060]

(Equation 1)

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

The softening point or melting point of the polyamide shown in Table 3 was measured using a trace melting point measuring device manufactured by Shibayama Seisakusho.

The results are shown in Table 1.
The test piece (see Table 1) showed no peeling even on a 2-inch mandrel as a result of the adhesion test. In the offset test, both the 55 kg paper and the 135 kg paper bleed the ink, there was no transfer at all, and the evaluation was 3. 130 ° C
And the melt viscosity at 10.0 mPa · s was stable. In addition, heat resistance ΔE * ab (heat) and light resistance ΔE * ab
(Light) achieved the target of 5 or less for all four colors.

Example 2 Fatty acid ester amide (T
he CP Hall Co., trade name: CPH-380N) was obtained in the same manner as in Example 1 by using DPX335-48% by weight.
11, 40% by weight, 10% by weight of a hydrocarbon resin (manufactured by Arakawa Chemical Co., trade name: Alcon P-100),
NEOPEN Blue 808, Oil Yellow 129, Oil P
Ink 330 and Oleosol Fast Black RL were added at 2% by weight, and hot-melt ink compositions of four colors were prepared in the same manner as in Example 1 (see Tables 1 and 2).

As is clear from Table 1, the results are shown in Example 2.
The test piece (see Table 1) showed no peeling even on a 2-inch mandrel as a result of the adhesion test. In the offset test, both the 55 kg paper and the 135 kg paper bleed the ink, there was no transfer at all, and the evaluation was 3. 130 ° C
, The melt viscosity was 12.0 mPa · s, and stable injection was performed.

Further, heat resistance ΔE * ab (heat) and light resistance
ΔE * ab (light) achieved the target of 5 or less for all four colors.

Example 3 Polyamide (Henkel, manufactured by Henkel, 32% by weight of CPH-380N and 20% by weight of hardened castor oil (manufactured by Kawaken Fine Chemicals, trade name: K3 wax) in the same manner as in Example 1) Product Name: DPX
-335-10), 20% by weight of bisamide (manufactured by Nippon Kasei, trade name: Slipax O), and a plasticizer (manufactured by Kawaken Fine Chemical, trade name: PM-72)
00T) Cyan hot melt ink composition was prepared in the same manner as in Example 1 by adding 6% by weight and further 2% by weight of NEOPEN Blue 808 (see Tables 1 and 2).

The results are shown in Table 1.
The test piece (see Table 1) showed no peeling even on a 2-inch mandrel as a result of the adhesion test. In the offset test, both the 55 kg paper and the 135 kg paper bleed the ink, there was no transfer at all, and the evaluation was 3. 130 ° C
And the melt viscosity was 11.0 mPa · s.

The heat resistance ΔE * ab (heat) and the light resistance ΔE
* Ab (light) achieved the target of 5 or less.

Example 4 Fatty acid esters (manufactured by Kuroda,
Trade name: synchro wax HR-C) 36% by weight, carnauba wax (manufactured by Noda Wax, trade name: deodorized purified carnauba wax No. 1) 32% by weight,
DPX-335-10 obtained by the same method as in Example 1 was added in an amount of 30% by weight, and Oil Pink 330 was added in an amount of 2% by weight, and a hot-melt ink of magenta was prepared in the same manner as in Example 1 (Table 1). To Table 2).

The results are shown in Table 1.
The test piece (see Table 1) showed no peeling even on a 2-inch mandrel as a result of the adhesion test. In the offset test, both the 55 kg paper and the 135 kg paper bleed the ink, there was no transfer at all, and the evaluation was 3. 130 ° C
, The melt viscosity was 12.0 mPa · s, and stable injection was performed.

The heat resistance ΔE * ab (heat) and the light resistance ΔE *
Ab (light) achieved the target of 5 or less.

Comparative Example 1 Instead of the polyamide of Example 1, 10% by weight of DPX335-11 not subjected to IPA treatment was added. Otherwise, a cyan hot melt ink composition was prepared in the same manner as in Example 1. (Table 1
To Table 2).

As is clear from Table 1, the results of the property evaluation performed in the same manner as in Example 1 show that the one in Comparative Example 1 (see Table 1) was peeled off even on a 2-inch mandrel as a result of the adhesion test. There was no at all. 55k offset test
Both the g paper and the 135 kg paper had no ink bleeding and no transfer, and the evaluation was 3. Melt viscosity at 130 ° C. is 9.
Stable injection was performed at 0 mPa · s, but heat resistance was ΔE *
The ab (heat) was 20 and the light fastness was ΔE * ab (light) of 16, indicating that the target could not be achieved.

[Comparative Example 2] 82% by weight of CPH-380N, 9% by weight of DPX335-11 not subjected to IPA treatment, 5% by weight of Alcon P-100, an antioxidant (trade name: Yoshinox, manufactured by Yoshitomi Pharmaceutical Co., Ltd.) 2246G) and 2% by weight of Oil Pink 330 were added, and a magenta hot melt ink was prepared in the same manner as in Example 1 (see Tables 1 and 2).

As is clear from Table 1, the results of the characteristic evaluation performed in the same manner as in Example 1 show that, in the case of Comparative Example 2 (see Table 1), peeling was observed on an 8-inch mandrel as a result of the adhesion test. occured. Offset test is 55kg paper, 1
The evaluation was 3 with 35 kg paper having no ink bleeding and no transfer. Melt viscosity at 130 ° C is 11.0mP
Stable injection could be performed at a · s, but heat resistance was ΔE * ab
(Heat) was 6, and light resistance was ΔE * ab (light) of 10. Thus, the target could not be achieved.

[Comparative Example 3] 35% by weight of CPH-380N, 41% by weight of DPX335-11 not subjected to IPA treatment, 20% by weight of Alcon P-100, an antioxidant (Yoshinox, manufactured by Yoshitomi Pharmaceutical Co., Ltd.) 2246G) to 2
The weight percent and 2% by weight of Oil Pink 330 were added, and the magenta hot melt ink composition was prepared in the same manner as in Example 1 (see Tables 1 and 2).

Comparative Example 3 (see Table 1)
Was as high as 20.0 mPa · s, and injection could not be performed.

[0079]

The hot-melt ink composition for ink-jet recording of the present invention improves the adhesion and weather resistance, which have conventionally been problems, and provides a high-quality clear image. In addition, it is possible to provide an ink-jet hot-melt ink which is excellent not only in the adhesiveness to a recording medium and in the recording storage performance such as prevention of offset but also in the weather resistance without further addition of an additive.

[Brief description of the drawings]

FIG. 1 is a graph showing the results of GPC analysis.

FIG. 2 is a graph showing the correlation between viscosity and temperature characteristics of polyamide.

FIG. 3 is a graph showing a relationship between a polyamide addition amount and a color change.

Claims (6)

[Claims] 1. An ink composition for use in an ink jet printing method for forming a recording dot by liquefying a solid ink at room temperature by heating and jetting it onto a recording medium, wherein a vehicle having an amide group is dissolved in an alkyl alcohol. An inkjet ink composition comprising a polyamide from which components have been removed. 2. The composition according to claim 1, wherein the molten component is a similar compound having a smaller molecular weight than the polyamide body.
The ink composition for inkjet according to the above. 3. The ink-jet ink composition according to claim 1, wherein the melting point of the polyamide from which the molten component has been removed is 90 ° C. or more and 130 ° C. or less. 4. The vehicle according to claim 1, wherein the vehicle has an amine value of at least 1.
10 to 40% by weight of polyamide
The ink composition according to any one of claims 1 to 3, wherein the ink composition contains 0.5% by weight or less and 5% by weight or less of a coloring agent having good stability with the vehicle. 5. The ink composition according to claim 1, wherein the coloring agent is Solvent Red 49. 6. A method for producing an ink composition for use in an ink jet printing method for forming a recording dot by liquefying a solid ink at room temperature by heating and jetting it onto a recording medium, wherein the polyamide is immersed in an alkyl alcohol. Thereafter, a method for producing an ink-jet ink composition comprising a step of filtering a molten component, a step of drying a polyamide on a filter paper, and a step of mixing the polyamide obtained in the above step with other vehicle components.