JPH0848898A - Method for controlling pigment particles, pigment obtained therefrom and coloring agent composition - Google Patents

Abstract

PURPOSE:To obtain particle controlled pigment having suitability required every dispersibility, fluidity, concentration, gloss, brightness, transparency, viscosity, stability with the passage of time and other uses by bringing a substantially water-insoluble solvent into contact with a pigment in a water system and provide a method for controlling the particles and obtain a coloring agent composition using the pigment. CONSTITUTION:This particle-controlled pigment is obtained by bringing pigment into contact with an aqueous dispersant obtained by uniformly dispersing a water-insoluble solvent into water by shear force produced in liquid in introducing water and a substantially water-insoluble solvent into a fluid system contracted in the diameter and having blending part and passing the liquid through contracted flow path while accelerating or by impulse force produced when accelerated liquid collides with each other or accelerated liquid collides with wall face constituting the flow path and then carrying out crystal growth of the pigment or control of particles due to transition of crystals. Furthermore, this controlling method is provided. This coloring agent compound comprises the particle controlled pigment and a vehicle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preparing particles in which a substantially water-insoluble solvent is brought into contact with a pigment in an aqueous system, and a particle-adjusted pigment and a colorant composition obtained by the method. The present invention provides a pigment having excellent suitability for inks, plastics, printing, toning agents, color toners and other coloring materials.

[0002]

2. Description of the Related Art Pigments are widely used in colorant compositions in the field of coloring materials, but workability and quality suitable for each application are required. For example, dispersibility, flowability, density, gloss,
Examples include sharpness, transparency, viscosity, stability over time, and other required items for each application. To impart these aptitudes,
In an aqueous system, particle preparation with a pigment solvent is generally performed. For example, as a method for adjusting particles by using a crude pigment as a pigment by crystal growth or crystal transition, there is disclosed in Japanese Unexamined Patent Publication No.
45659, JP-A-2-73869, and JP-A-1-259.
068, JP-A-63-199769, JP-A-62-13
1072 describes a method for adjusting the particles of a pigment by crystal growth, JP-A-55-48254, and the 35th pigment introductory course text (Color Materials Association).

The preparation of pigment particles with these solvents is based on the fact that the pigment is mainly produced in an aqueous system, and that the treatment with an aqueous system in which fine particles exist without dry aggregation of the pigment is effective. Is being done in. Regarding the water-soluble solvent, solvents such as lower alcohols, polyhydric alcohols, and ketones have been conventionally used as pigment particle modifiers in order to impart the above-mentioned suitability. However, since a water-insoluble solvent cannot be treated in water alone by itself, various improvements have been added to the water-insoluble solvent.

A substantially water-insoluble solvent is emulsified with a surfactant and treated in an aqueous system.
The substantially water-insoluble solvent that can be emulsified is limited. In addition, surface modification with an emulsion causes a gravure ink, bleeding with paint, poor water resistance, migration with plastics, poor emulsification suitability with ink, etc. because the surfactant is contained in the pigment, and the application is There are limited drawbacks. Further, there is a drawback that the particle size of the emulsified substantially water-insoluble solvent is too large for the pigment particles and the pigment particle adjusting effect is weak.

[0005]

An object of the present invention is to provide a pigment particle preparation method and a particle preparation pigment in which a substantially water-insoluble solvent is brought into contact with a pigment in an aqueous system. A further object of the present invention is to add a substantially water-insoluble solvent to an aqueous system without using a surfactant or to add a small amount within a range such that a mixture of water and the substantially water-insoluble solvent does not completely emulsify. The present invention provides a pigment particle preparation method and a particle preparation pigment in which the pigment is brought into contact with the pigment.

[0006]

That is, according to the present invention, water and a substantially water-insoluble solvent are pressurized to a high pressure and introduced into a flow path system having a bent portion with a reduced diameter to accelerate the liquid. Due to the shearing force generated in the liquid while passing, or
An aqueous dispersion in which water and the substantially water-insoluble solvent are uniformly dispersed by the impact force when the accelerated liquids collide with each other or when the accelerated liquid collides with the wall surface forming the flow path. And a pigment are brought into contact with each other to perform crystal growth or crystal transition of the pigment. Further, the present invention relates to the pigment obtained by the above pigment preparation method. The present invention further relates to a colorant composition comprising the above pigment and a vehicle. The ultra-high pressure disperser can be used without particular limitation as long as it is an apparatus capable of obtaining a collision pressure of 200 Kg / cm ² or more, and examples thereof include a homogenizer (manufactured by Gorin Co.) and a nanomizer (manufactured by Nanomizer Co.).
Etc.

The schematic internal structure of the ultra-high pressure disperser is shown in FIGS.
It was shown to. In FIG. 1, water and a substantially liquid insoluble solvent, which are made to flow in the direction of the arrow at a high pressure, for example, at a pressure of 200 Kg / cm ² or more from the flow channels 1 and 2, are mixed beforehand or preliminarily mixed. The case where the mixed liquids are respectively put into the flow paths 3 and 4 and collided in the vicinity of the inlet of the flow path 5 and discharged from the flow path 5 is shown. FIG. 3 shows a case in which the liquid that has flowed in from the flow paths 7 and 8 at a high pressure in the direction of the arrow collides near the flow path 9 and is discharged from the flow path 10. FIG. 5 shows a case where the water that has flowed in at high pressure from the flow path 11 and the mixed liquid of the substantially water-insoluble solvent collide with the wall surface 14 and are discharged from the flow path 13.

The pigment of the present invention contains organic and inorganic substances. Specifically, it is a pigment described as CI pigment in the color index (CI). As for the form of the pigment, it is preferable to use the pigment produced in an aqueous system in the form of an aqueous slurry in order to bring the water-insoluble solvent into contact with the solvent uniformly and effectively. The dry powdery pigment is preferably used as it is in the case of a solvent having a high wettability, but in the case of a solvent having a low wettability, a sand mill, a ball mill, an attritor, a paint conditioner, a disperser such as a high speed mixer is used. It may be used in the present invention after or during dispersion in water.

Regarding pigments produced in organic solvents,
As in the above, it may be used in the present invention in the form of dry powder, or after removing the organic solvent and substituting with an aqueous slurry, or after dispersing in water, and further during dispersion.

As the substantially water-insoluble solvent of the present invention,
A liquid which is water-insoluble or hardly soluble at room temperature, has crystal growth or crystal transition ability of the pigment, and can be removed from the pigment by heating is preferable. For example, n-hexane,
Hydrocarbons such as n-heptane, n-octane, n-decane, 2,2-dimethylbutane, petroleum benzene, mineral spirits, cyclohexane, methylcyclohexane, benzene, toluene, xylene, ethylbenzene, isopropylbenzene, solvent naphtha, turpentine, etc., Chloroform, carbon tetrachloride, ethylene chloride, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, trichloroethylene, tetrachloroethylene, halogenated hydrocarbons such as chlorobenzene, 3-pentanol, n-hexanol, n -Alcohols such as heptanol and nonyl alcohol, dichloroethyl ether, n-
Ethers such as dibutyl ether, ketones such as methyl-n-propyl ketone, methyl-n-butyl ketone, ethyl-n-butyl ketone, ethyl acetate, acetic acid-n-propyl acetate, acetic acid n-butyl, isobutyl acetate, acetic acid-n- Examples thereof include esters such as amyl, carbon disulfide, and mixed solvents thereof.

The amount of the substantially water-insoluble solvent with respect to the pigment is not particularly limited depending on the use of the pigment, but normally, the amount of the substantially water-insoluble solvent is 0.5 to 100 parts by weight with respect to 100 parts by weight of the pigment.
300 parts by weight is preferable, and 1 to 200 parts by weight is more preferable. If it is less than 0.5 part by weight, the effect of the water-insoluble solvent is practically negligible, and if it is used in excess of 300 parts by weight, the effect of the amount used cannot be obtained.

The aqueous dispersion of the present invention can be obtained by using an ultra-high pressure disperser to collide water with a substantially water-insoluble solvent at high pressure in the absence of a surfactant, but it can be obtained substantially by water. Further, a surfactant may be added to the extent that the mixture of the water-insoluble solvent is not completely emulsified. The pressure for collision crushing is preferably 200 kg / cm ² or more, and the higher the pressure, the more stable the aqueous dispersion can be obtained. If the pressure is less than 200 kg / cm ² , the water-insoluble solvent is practically separated from water and it is difficult to obtain an aqueous dispersion.

The water-based dispersion of the present invention is preferably obtained by ultrahigh pressure dispersion while quantitatively supplying water and a solvent, but immediately after premixing with a mixer such as a high speed mixer or homomixer, the ultrahigh pressure is applied. It may be dispersed. The amount of the substantially water-insoluble solvent with respect to water is 1 to 80% by weight.
It may be appropriately selected within the range. The higher the concentration, the better the production efficiency, but if it exceeds 80% by weight, it is difficult to obtain an aqueous dispersion, and if it is less than 1% by weight, not only the production efficiency is poor, but also the aqueous dispersion becomes difficult to obtain. -60% by weight is more preferable.

The particle-adjusted pigment of the present invention is obtained by adding an aqueous dispersion to the pigment and stirring and mixing, or by dispersing with a disperser such as a sand mill, a ball mill, an attritor, a paint conditioner or a high speed mixer. It is preferable to add the water-based dispersion to the water-based slurry of the pigment in which the particles are present in a fine state, because the water-insoluble solvent can be substantially brought into contact with the water-based dispersion. The temperature of stirring and mixing or dispersion can be arbitrarily set from normal temperature to the boiling point of water, or from the azeotropic point of water and the solvent, but heating promotes particle adjustment by crystal growth or crystal transition of the pigment, and It is preferable to remove the solvent by volatilization.

The particle-modified pigment of the present invention is recovered by filtration and washing with water by a conventional method. Moreover, you may use together the additive for surface treatments if needed. The particle-conditioning pigment of the present invention may be used as it is in a paste form, or may be dried or pulverized and used in a powder form.

The colorant composition of the present invention is obtained by dispersing the particle-modifying pigment in at least one kind of vehicle resin and solvent, and examples thereof include offset ink, gravure ink, paint, plastic and water-based color. The vehicle used is not particularly limited, and may contain an auxiliary agent or an extender pigment. To disperse the colorant composition of the present invention, it is preferable to use a disperser such as a dissolver, a high speed mixer, a homomixer, a sand mill, an attritor, two rolls, and three rolls. The shape of the particle-adjusting pigment is generally dispersed by using a powder, but in the case of a water-based colorant composition, or for offset inks and polyethylene, a paste-like material in which the drying step is omitted is used. It is also possible to disperse the particle-modifying pigment directly.

Examples of the vehicle for offset ink of the present invention include rosin-modified phenolic resin, petroleum resin, alkyd resin, and drying oil-modified resins thereof such as 20 to 5
0% by weight and 0 to 3 dry oils such as linseed oil, tung oil and soybean oil
Examples of the solvent include 0% by weight, and 10 to 60% by weight of a solvent such as n-paraffin, isoparaffin, aromatech, naphthene and α-olefin.

Examples of vehicles for gravure ink include:
Gum rosin, wood rosin, tall oil rosin, lime rosin, rosin ester, maleic acid resin, polyamide resin, vinyl resin, nitrocellulose, cellulose acetate,
Ethyl cellulose, chlorinated rubber, cyclized rubber, ethylene-vinyl acetate copolymer resin, polyurethane resin, polyester resin, alkyd resin, acrylic resin, gilsonite, dammar, shellac, etc., or a mixture thereof, or
A water-soluble resin obtained by making the above resin or a mixture thereof water-soluble, or an emulsion resin 10 to 50% by weight and a solvent such as hydrocarbon, alcohol, ketone, ether alcohol, ether, ester or water 30 to 80% by weight. Is mentioned.

Examples of vehicles for paints include acrylic resins, alkyd resins, epoxy resins, chlorinated rubber, vinyl chloride, synthetic resin emulsions, silicone resins, fluororesins, polyurethane resins, polyester resins, melamine resins, urea resins and the like. Or a water-soluble resin obtained by water-solubilizing the above resin or a mixture thereof, or 20 to 80% by weight of an emulsion resin and a solvent such as hydrocarbon, alcohol, ketone, ether alcohol, ether, ester or water 10 to 60 It may be composed of weight%.

Examples of vehicles for plastics include polyethylene, polypropylene, polybutadiene, ethylene ionomer, polyvinyl chloride, polyvinylidene chloride, ABS resin, acrylic resin, methacrylic resin, polyvinyl alcohol, cellulose plastic, epoxy resin, polyester resin. , Phenol resin, urea resin, melamine resin, polyurethane resin, silicone resin,
Polyamide resin, polystyrene, polyacetal, polycarbonate, polyphenylene ether, polyphenylene sulfite, polysulfone, polyetherimide,
Examples thereof include polyether ketone, and composites thereof.

Examples of aqueous color vehicles include nonionic, anionic and cationic surfactants, sulfonic acid amides and hydroxystearic acid surfactants.
At least one selected from ε-caprolactam-based polymer dispersants, polyhydric alcohols such as glycerin, ethylene glycol, triethylene glycol, propylene glycol, and pentaerythritol, water, if necessary amines, preservatives, defoaming agents, etc. The thing which consists of an auxiliary agent of is mentioned.

[0022]

According to the present invention, a substantially water-insoluble solvent and water are supplied at a desired ratio, pressurized at a pressure of 200 Kg / cm ² or more, and caused to collide with each other in the absence of a surfactant. Alternatively, addition of a small amount within a range in which a mixture of water and a substantially water-insoluble solvent is not completely emulsified provides an aqueous dispersion which has been impossible up to now. This is considered to be because the collision under high pressure causes the water-insoluble solvent to be finely divided to a molecular level, and a stable aqueous dispersion is generated due to the intermolecular attractive force between water and the water-insoluble solvent. To be The particle-adjusted pigment of the present invention is substantially in contact with a water-insoluble solvent at the molecular level on the surface of the pigment particle, so that the contact area per unit weight of the solvent with respect to the pigment becomes large as compared with the conventional contact at the emulsion particle level, An excellent effect can be obtained with a small amount in adjusting particles by crystal transition or crystal growth of the pigment.

[0023]

The present invention will be described below with reference to examples. In the examples, “part” means “part by weight” and “%” means “% by weight”. Example 1 90 parts of water and 10 parts of xylene were collided with Nanomizer (manufactured by Nanomizer Co., Ltd.) at a pressure of 1300 Kg / cm ² by repeating 3 times to obtain an aqueous dispersion. 50 parts of this aqueous dispersion was added to an aqueous slurry prepared by dispersing 100 parts of 2000 parts of CI Pigment Yellow 12 synthesized by a conventional method in 2000 parts of water, stirred and mixed for 30 minutes, and then heated to 80 ° C. for another 30 minutes. Mix with stirring. After filtration and washing with water, 99 parts of a paste-like particle-modified pigment in terms of a dried product was obtained. The particle shape of this particle-adjusted pigment by an electron microscope was uniform, whereas Comparative Example 1 was not uniform. Further, the offset ink using this particle-adjusted pigment showed a gloss superior to that of Comparative Example 1, and the surface tension of the emulsified water of the offset ink was 70 dyne / cm, while Comparative Example 1 had 59 dyne / cm. cm and showed excellent emulsification suitability. Comparative Example 1 89 parts of water, 10 parts of xylene, and 1 part of a nonionic activator (Nonal 310 manufactured by Kao) were mixed with a high speed mixer to obtain an emulsion. The same operation was performed except that 50 parts of this emulsion was changed to the aqueous dispersion of Example 1 to obtain 98 parts of a paste-like comparative pigment in terms of a dry product. Comparative Example 2 In Example 1, the operation of colliding at a pressure of 100 kg / cm ² was repeated 5 times, but the oil layer and the water layer were immediately separated, and an aqueous dispersion could not be obtained. Also, an aqueous dispersion cannot be obtained by homomixer dispersion or sand mill dispersion,
It was not possible to treat the pigment with an aqueous system.

Example 2 89.95 parts of water and 10 parts of xylene were added to a nonionic active material.
Addition of 0.05 parts of agent (Nonal 310 manufactured by Kao)
Mixed with a speed mixer. This mixture is partially
Formation was observed, but most of the water and xylene
It was in a separated state. Add this mixture to the Nanomizer
Made by Nomizer), 300 kg / cm ²Collision at pressure
This operation was repeated 3 times to obtain an aqueous dispersion. Implemented below
Carry out the same operation as in Example 1 to obtain a dry matter conversion pace of 99 copies.
A pigment-like particle-modified pigment was obtained. Electron microscopy of this particle-conditioned pigment
The particle shape by the mirror is uniform,
The offset ink used has a gloss superior to that of Comparative Example 1.
In addition, the surface tension of the offset ink emulsified water is
It was 67 dyne / cm 2, showing excellent emulsification suitability.

Example 3 A dry type attritor having a capacity of 1 liter was filled with 2 kg of a steel ball having a diameter of 8 mm, 150 parts of crude copper phthalocyanine (CI Pigment Blue 15: 3) was charged, and the rotation speed was 500.
After dry grinding for 2 hours at an internal temperature of 60 ° C. at rpm, the pigment powder was taken out. On the other hand, 500 parts of water and tetrachloroethylene 5
0 parts of Gorin (made by Gorin Co., Ltd.), 500 kg / cm
^The operation of colliding at a pressure of ² was repeated 3 times to obtain an aqueous dispersion. Into this water-based dispersion, the dry-pulverized pigment powder 1
After stirring and mixing 00 parts at 90 ° C. for 30 minutes, filtration, washing with water and drying were performed to obtain 98 parts of a particle-adjusted pigment. The surface tension of the emulsified water of the offset ink using this particle-adjusted pigment is 71 dyne / c.
In contrast to m 3, Comparative Example 3 showed 53 dyne / cm 2, showing excellent emulsification suitability. Comparative Example 3 498 parts of water, 50 parts of tetrachloroethylene, and 2 parts of an anionic activator (Demol N made by Kao) were mixed with a high speed mixer to obtain an emulsion. The same operation was carried out except that this emulsion was changed to the aqueous dispersion of Example 3 to obtain 97 parts of a comparative pigment.

Example 4 The same operation as in Example 3 was carried out except that tetrachloroethylene was changed to n-dibutyl ether to obtain 97 parts of a particle-adjusted pigment. The surface tension of the emulsified water of the offset ink using this particle-adjusted pigment was 68 dyne / cm, which showed excellent emulsification suitability.

Example 5 60 parts of water and 40 parts of nonyl alcohol were collided with a Nanomizer (manufactured by Nanomizer Co., Ltd.) at a pressure of 1000 kg / cm ² three times to obtain an aqueous dispersion. After 10 parts of this aqueous dispersion was pigmented with crude copper phthalocyanine by a kneader by a conventional method, 100 parts of a CI Pigment Blue 15: 3 dry product obtained by separating the kneading auxiliary was converted to water. The mixture was added to the aqueous slurry dispersed in 1000 parts, stirred and mixed for 30 minutes, filtered, washed with water and dried to obtain 98 parts of a particle-adjusted pigment. In the production of the offset ink by the 3-roll dispersion of this particle-adjusted pigment, it took 2 passes to reach 5 μm or less, whereas the pigment not subjected to particle adjustment with a solvent requires 4 passes, and thus has excellent dispersibility. showed that.

Example 6 70 parts of water and 30 parts of n-butyl acetate were collided with a Nanomizer (manufactured by Nanomizer Co., Ltd.) at a pressure of 1000 kg / cm ² three times to obtain an aqueous dispersion. 10 parts of this water-based dispersion was converted into 100 parts by weight of 200 parts of water in terms of a dry product of CI Pigment Red 57: 1 synthesized by an ordinary method.
The resulting mixture was added to 0 part of an aqueous slurry, stirred and mixed at 80 ° C. for 30 minutes, filtered, washed with water and dried to obtain 97 parts of a particle-adjusted pigment. The viscosity of the gravure ink using this particle-adjusted pigment was 630 cps, whereas the viscosity of the gravure ink using a pigment without solvent adjustment was 3200 cps.
s and showed excellent flow properties.

Production Example of Offset Ink 16 parts of pigment and 54 parts of rosin-modified phenol resin varnish were mixed and dispersed with 3 rolls to prepare a base ink.
Rosin-modified phenolic resin varnish 2 on this base ink
An offset ink was prepared by mixing 0 parts and 10 parts of the solvent for the offset ink.

Production Example of Gravure Ink 10 parts of pigment, 70 parts of varnish of polyamide and nitrocellulose, and 20 parts of ethyl acetate are placed in a 225 ml mayonnaise bottle together with 300 g of 3 mmφ steel balls and dispersed with a paint conditioner for 1 hour to prepare a gravure ink. did.

[0031]

INDUSTRIAL APPLICABILITY As described above, the particle-adjusted pigment of the present invention uses a substantially water-insoluble solvent, which cannot be used conventionally, as a pigment modifier in an aqueous system, and the pigment particles are formed by crystal transition or crystal growth of the pigment. It shows an excellent effect in adjustment. Further, since the particle-conditioning pigment of the present invention does not contain a surfactant, or because a small amount of a mixture of water and a substantially water-insoluble solvent does not completely emulsify, it is caused by the surfactant. There is no adverse effect,
It can be used in a colorant composition without any limitation.

[Brief description of drawings]

FIG. 1 is a sectional view showing the internal structure of an ultra-high pressure disperser.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view showing the internal structure of another ultra-high pressure disperser.

4 is a sectional view taken along line IV-IV of FIG.

FIG. 5 is a sectional view showing the internal structure of another ultra-high pressure disperser.

6 is a sectional view taken along line VI-VI of FIG.

[Explanation of symbols]

 1 to 5 flow path 6 high-pressure disperser main body 7 to 14 flow path 15 flow path partition wall

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area C09C 3/08 PBU

Claims (14)

[Claims] 1. Water and a substantially water-insoluble solvent are pressurized under high pressure to be introduced into a flow path system having a bent portion with a reduced diameter, and shear generated in the liquid while passing through while being accelerated. Water and the above-mentioned substantially water-insoluble solvent are uniformly dispersed by force, or by the impact force when the accelerated liquids collide with each other or when the accelerated liquid collides with the wall surface forming the flow path. A method for preparing a pigment, which comprises contacting a water-based dispersion soaked with a pigment to carry out crystal growth or crystal transition of the pigment. 2. The method for preparing a pigment according to claim 1, wherein the substantially water-insoluble solvent is an organic solvent which is insoluble or slightly soluble in water at room temperature and can be removed by heat. 3. The method for preparing a pigment according to claim 1, wherein water and the substantially insoluble solvent are preliminarily mixed before being brought to a high pressure. 4. The flow system introduces water and a substantially water-insoluble solvent individually or a mixed liquid prepared by preliminarily mixing water and a substantially water-insoluble solvent, at least 2
The pigment preparation method according to claim 1, comprising individual channels, a channel in which a channel system for colliding the introduced high-pressure liquids is reduced, and a channel for discharging the colliding high-pressure liquids. 5. The pigment preparation method according to claim 1, wherein the flow path system comprises a flow path into which one high-pressure liquid is introduced and at least one flow path having a reduced diameter. 6. A mixture of water and a substantially water-insoluble solvent comprises:
The pigment preparation method according to claim 1, which is carried out at a concentration of the water-insoluble solvent of 1 to 80% by weight. 7. The pigment preparation method according to claim 1, wherein the high pressure is a pressure of 200 Kg / cm ² or more. 8. A pigment obtained by the method for preparing a pigment according to claim 1. 9. A colorant composition comprising the pigment according to claim 8 and a vehicle. 10. The colorant composition according to claim 9, wherein the vehicle is a vehicle for offset ink. 11. The colorant composition according to claim 9, wherein the vehicle is a vehicle for gravure ink. 12. The colorant composition according to claim 9, wherein the vehicle is a vehicle for paints. 13. The colorant composition according to claim 9, wherein the vehicle is a vehicle for plastics. 14. The colorant composition according to claim 9, wherein the vehicle is an aqueous color vehicle.