JP2006299138A - Method for producing pigment composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problems that the conventional batch type kneader and the like raises, problems of the restricted production scale, consumption of much electric energy, insufficient transparency of the obtained pigment and the like. <P>SOLUTION: The manufacturing method of the pigment composition comprises kneading a mixture that consists of an organic pigment, a water-soluble inorganic salt, a water-soluble organic liquid and a resin in a continuous kneading machine that has pulverizing spaces formed in the gap parts between the annular fixed disks and the rotating disks that are concentric with the fixed disks that rotate as one body around the axial center of the driving shaft. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a pigment composition in which particles of color developing particles are finely sized to have a uniform particle size and extremely dispersible with respect to a vehicle. More specifically, the present invention relates to a pigment composition that gives good gloss and high coloring power to a color development product when particles of color developing powder are dispersed in a vehicle such as a gravure ink or an offset ink or a vehicle such as a paint. The present invention relates to a method for manufacturing a product.

Some organic pigments, such as azo pigments, can obtain finely sized particles by selecting appropriate reaction conditions during synthesis. In addition, very fine and agglomerated particles produced during synthesis, such as polyhalogenated copper phthalocyanine pigments, are grown and sized in the subsequent process, and coarse and irregular particles produced during synthesis, such as copper phthalocyanine pigments. Some of them perform a process called pigmentation, which is refined and sized in a later step.
For example, copper phthalocyanine pigments are used in large quantities and widely in the field of color material industry because of their beautiful color tone, high tinting strength, and good performance such as weather resistance and heat resistance.
Usually, a copper phthalocyanine pigment is an alkylbenzene in the presence or absence of a catalyst such as ammonium molybdate or titanium tetrachloride, or phthalodinitrile or a derivative thereof and urea and a copper source, or phthalodinitrile or a derivative thereof and a copper source. , By reacting in an organic solvent such as trichlorobenzene or nitrobenzene at normal pressure or under pressure.
However, the synthesized phthalocyanine molecules can be obtained only in coarse and needle-like particles having a major axis of about 10 to 200 μm by causing particle growth one after another in the synthesis solvent, such as inks, paints, plastics, etc. As a coloring pigment, the value is very low and it is called crude copper phthalocyanine. Accordingly, the crude copper phthalocyanine has high color utility value. There are various known examples of methods for industrially refining crude copper phthalocyanine, such as a mixture of crude copper phthalocyanine and sodium chloride with a small amount of diethylene glycol, etc. There is a so-called solvent salt milling method in which a solvent is added and moistened with a ball mill, an attritor, or a batch kneader and wet-ground (see Patent Document 1 and Patent Document 2). In this method, sodium chloride, diethylene glycol and the like are removed from the obtained kneaded product by washing with water and dried to obtain a copper phthalocyanine pigment with fine primary particles.
However, conventional batch type kneaders have problems such as production scale limitations derived from the batch type, variation in quality for each lot, contamination of the work environment due to foreign matter contamination and dust generation due to the open type.
In addition, there is a limit to the use of enormous energy for the miniaturization of organic pigments and the level of miniaturization. Furthermore, even when the obtained copper phthalocyanine pigment is used dispersed in a vehicle such as gravure ink, offset ink or printing ink or paint, improvement of gloss and coloring power is always a required issue. there were.
Japanese Patent Laid-Open No. 7-53889 JP-A-5-43704

The present invention has been made in view of such a situation, and is due to restrictions on production scale, variations in quality for each lot, problems due to the open type, contamination by foreign matter, and generation of dust. It aims at providing the manufacturing method of the pigment which solves the pollution of a working environment, etc.
Furthermore, the present invention can obtain finer particles with a small amount of energy as compared with conventional batch kneaders, etc., and is dispersed in a vehicle such as gravure ink, offset ink or printing ink or paint. Produces pigments that, when used, give good extensibility and color strength to developed products, and give excellent suitability even in applications that require finer pigment particles such as inkjet inks and color filters. It aims to provide a method. That is, an object of the present invention is to provide a method for efficiently producing a fine pigment that cannot be obtained by a conventional batch kneader or the like in a short time.

  The present invention provides a mixture of an organic pigment, a water-soluble inorganic salt, a water-soluble organic liquid and a resin, with a gap between an annular fixed disk and the fixed disk concentrically rotating about the axis of the drive shaft. The present invention relates to a method for producing a pigment composition characterized by kneading in a continuous kneader having a pulverizing space formed in a part.

  Compared to conventional batch type kneaders, production scale is less restricted and timely and appropriate quantity production is possible. There is less variation in the quality of each product lot, and it becomes a sealed type. Eliminates problems such as contamination and can be pulverized to finer particles with a small amount of energy, and organic pigments obtained from this manufacturing method are dispersed in vehicles such as gravure inks, offset inks, or paint inks or paints In this case, the pigment gives the developed product good gloss and coloring power, and further improves the gloss and coloring power, and is particularly suitable for applications requiring transparency.

First, a continuous kneader used for carrying out the method of the present invention will be described with reference to FIG. FIG. 1 is a side sectional view showing an embodiment of a continuous kneader according to the present invention. Incidentally, a continuous kneader suitably used in the present invention is described in Japanese Patent Publication No. 2-92, for example, a continuous kneader 10 (“Miracle K.C. K. ") can be mentioned as suitable.
As shown in FIG. 1, the continuous kneader 10 has a basic configuration including a feed unit 1, a kneading unit 2, a discharge unit 3, and a quantitative feeder unit 4. The feed portion 1 includes a cylindrical casing 11 that extends in the horizontal direction, and a spiral rod 12 that is concentrically fitted into the casing 11 and is fitted in a sliding contact state. On the upper surface of the casing 11 on the upstream side, a raw material receiving port 111 for receiving the raw material from the quantitative feeder section 4 is opened. The spiral rod 12 is concentrically fixed to a drive shaft 121 of a drive motor (not shown) at the base end (right side in FIG. 1), and rotates about the shaft center via the drive shaft 121 by driving the drive motor. It is like that. A spiral fin 122 screwed in a predetermined direction is provided on the outer peripheral surface of the spiral rod 12, and the raw material supplied from the metering feeder unit 4 is sent to the kneading unit 2 by rotation around the axis of the spiral fin 122. It is designed to be pumped towards.
The quantitative feeder section 4 is a raw material to be subjected to continuous kneading treatment (in the present invention, a mixture of an organic pigment, a water-soluble inorganic salt, a water-soluble organic liquid, and a resin that exhibits a sol or gel shape). A feed hopper 41 for containing the feed, a spiral feeder 42 for feeding the feed cut out from the bottom of the feed hopper 41 toward the feed 1, and a spiral feeder 42 for feeding the feed 1. The casing 11 is provided with a connecting cylinder 43 standing from the peripheral edge of the raw material receiving port 111 so as to cover the downstream end.
The spiral feeder 42 is mounted in a state in which a spiral fin is slidably contacted in an interposed cylinder 44 interposed between the bottom opening of the raw material hopper 41 and the upper opening of the connecting cylinder 43, and the proximal end side ( The right side in FIG. 1 is concentrically connected to a drive shaft of a feed motor (not shown). Therefore, the raw material in the raw material hopper 41 is conveyed by the spiral feeder 42 by rotating around the axis of the spiral feeder 42 driven by the feed motor, and is introduced into the casing 11 in advance via the interposed cylinder 44 and the connecting cylinder 43. It is designed to be supplied with a set conveyance amount.
The kneading section 2 includes a plurality of fixed disks 21, annular kneading cylinders 22 arranged alternately with the fixed disks 21 while being sandwiched between the fixed disks 21, front and back surfaces (the left and right surfaces in FIG. 1). ) Is provided with a rotating disk 23 concentrically inserted into the kneading cylinder 22 in a state of facing the fixed disk 21. A tie rod (not shown) is passed through the plurality of fixed disks 21 and kneading cylinders 22, and a base end portion of the tie rods is fixed to the casing 11 of the feed portion 1, whereby the fixed disks 21 and the kneading cylinders 22 are fed. It is integrated with part 1.
Each of the rotating disks 23 is externally fitted on a spline shaft (not shown) that is concentrically provided from the distal end surface of the spiral rod 12. A cylindrical intermediate screw 24 is interposed between the adjacent rotating disks 23, so that the rotating disks 235 and the screws 24 are alternately mounted on the spline shaft. The rotating disk 23 has an outer diameter dimension set to be slightly smaller than the inner diameter dimension of the fixed disk 21, and the intermediate screw 24 has an outer diameter dimension set to be slightly smaller than the inner diameter dimension of the rotating disk 23. Each rotary disk 23 and each intermediate screw 24 are alternately fitted on the spline shaft, and the outer peripheral surface thereof passes through a gap through which the raw material can pass with respect to the inner peripheral surface of the kneading cylinder 22 and the fixed disk 21. They are designed to face each other.
According to the configuration of the continuous kneader 10, the raw material loaded in the raw material hopper 41 is discharged from the bottom of the raw material hopper 41 by driving the spiral feeder 42, and is connected via the interposed cylinder 44 and the connecting cylinder 43. It is introduced into the casing 11 of the feed part 1. The raw material introduced into the casing 11 is sequentially conveyed toward the kneading unit 2 on the downstream side by the rotation of the spiral fins 122 by the driving rotation of the spiral rod 12.
The raw material transported to the kneading unit 2 is first of all the outer peripheral surface of the intermediate screw 24 on the most upstream side (right side in FIG. 1) rotating around the axis and the drive shaft 121 on the most upstream side. 1 passes between the peripheral surface, and subsequently passes between the left side surface in FIG. 1 of the uppermost fixed disk 21 and the right side surface of the uppermost rotating disc 23 rotating around the axis, The raw material is kneaded when passing through these gaps. The kneading operation for the raw material is repeated in a plurality of stages for the amount of installation of the fixed disk 21, the kneading cylinder 22, the rotating disk 23, and the intermediate screw 24, whereby a plurality of components of the raw material (in the present invention, organic pigment, water Kneading treatment is performed on the inorganic salt, water-soluble organic liquid and resin). The product obtained by the completion of the kneading process is discharged to the outside through the gap between the outer peripheral surface of the rotating disk 23 on the most downstream side and the inner peripheral surface of the fixed disk 21, that is, the discharge unit 3.
2 is a front view (viewed from the right side of FIG. 1) or a rear view (viewed from the left side of FIG. 1) showing an embodiment of a fixed disk and a rotating disk applied to the continuous kneader shown in FIG. (A) is a cavity fan-shaped fixed disk 21a, (b) is a cavity fan-shaped rotating disk 23b, (c) is a cavity chrysanthemum-shaped fixed disk 21c, and (d) is a cavity chrysanthemum mold. The rotating disks 23d and (e) show the cavity mortar-shaped fixed disk 21e, and (f) shows the cavity mortar-shaped rotating disk 23f, respectively.
As shown in FIG. 2, the fixed disk 21 is provided with a loose fitting hole 211 for loosely fitting to the concentric intermediate screw 24, and the front and back surfaces (front side and back surface) of the fixed disk 21. A plurality of concave portions (cavities (crushing spaces) 212) having an equal pitch are provided in the circumferential direction, which are recessed in the radial direction from the loose fitting holes 211. On the other hand, the rotating disk 23 is provided with an outer fitting hole 231 for fitting in close contact with a spline shaft (not shown) formed concentrically and on the front and back surfaces of the rotating disk 23, A cavity (crushing space) 232 corresponding to the cavity 212 of the disk 21 is recessed. The cavity 232 of the rotating disk 23 is open at the periphery.
Then, the raw material introduced into the gap between the fixed disk 21 and the rotating disk 23 is sequentially pushed into the cavities 212 and 232 by being pressed by the drive of the spiral rod 12, and in this state the rotating disk 23 is pivoted. By rotating around the center, a shearing force is applied to the raw material in each of the cavities 212 and 232 at the interface between the cavities 212 and 232. That is, the raw materials in the cavities 212 and 232 of the fixed disk 21 and the rotating disk 23 facing each other are sliced at the ridges of the ridges of the cavities 212 and 232, and the raw materials are replaced with shearing force (sheared raw materials). Are released from the cavities 212 and 232, and new raw materials enter the cavities 212 and 232), whereby the raw materials are kneaded and dispersed.
The fixed disk 21 and the rotating disk 23 are formed into the cavity fan-shaped fixed disk 21a and the cavity fan-shaped rotating disk 23b shown in FIGS. 2 (a) and 2 (b) according to the shape of the cavities 212 and 232, and FIG. Cavity chrysanthemum type fixed disk 21c and cavity chrysanthemum type rotary disk 23d shown in (c) and FIG. 2 (d), cavity mortar type fixed disk 21e and mold shown in FIG. 2 (e) and FIG. 2 (f). The reason why it is divided into a plurality of types with the tee mortar type rotating disk 23f is to increase the shearing force on the raw material as the kneading and dispersing process proceeds.
That is, the porosity of each cavity 212, 232 (the ratio (%) of the area of each cavity 212, 232 to the surface area of the fixed disk 21 and the rotating disk 23) is the fan-shaped cavities 212, 232, chrysanthemum. The mold cavities 212 and 232 and the mortar mold cavities 212 and 232 decrease in this order, but the shearing force on the raw material increases as the porosity decreases.
In the present embodiment, the cavities 212 and 232 have the fan-shaped fixed disk 21 and the rotation from the upstream side toward the downstream side in order to increase the shearing force on the raw material as the kneading and dispersing process proceeds on the raw material. The disk 23, the cavities 212, 232 are arranged in a chrysanthemum-shaped fixed disk 21 and the rotating disk 23, and the cavities 212, 232 are arranged in the mortar-shaped fixed disk 21 and the rotating disk 23 in this order.
By doing so, a large shearing force does not act on the raw material suddenly, but as the kneading and dispersing process proceeds, the shearing force on the raw material gradually increases. As a result, the organic pigment, the water-soluble inorganic salt, the water-soluble organic liquid and the resin, which are constituents of the raw material, can be reliably kneaded and dispersed with each other.
Further, according to the continuous kneader 10 having such a configuration, when the organic pigment that is one of the constituent elements of the raw material is composed of coarse particles, the organic pigment is separated from the gap between the fixed disk 21 and the rotating disk 23 (particularly, By being introduced into each of the cavities 212 and 232), the organic pigment can be pulverized by applying a shearing force to the coarse particles by the rotation of the rotating disk 23.
On the other hand, when the organic pigment is composed of agglomerates of fine particles, the agglomerates are introduced into the gaps (in particular, the respective cavities 212 and 232) between the stationary disk 21 and the rotating disk 23, so The aggregate can be reliably crushed and sized by rotation.
Hereinafter, the pigment that is kneaded and dispersed by the continuous kneader 10 will be described in detail. The pigment composition of the present invention comprises an annular fixed disk 21 and a fixed disk 21 that integrally rotates a mixture of an organic pigment, a water-soluble inorganic salt, a water-soluble organic liquid and a resin around the axis of the drive shaft 121. It is obtained by kneading in a continuous kneader 10 having a pulverizing space formed in a gap portion with a concentric rotating disk 23.
The organic pigment used in the present invention can be obtained by selecting appropriate reaction conditions at the time of synthesis, such as an azo pigment, and can be obtained as finely sized particles, synthesized like a polyhalogenated copper phthalocyanine pigment. It means that particles that are sometimes finely aggregated and agglomerated in the subsequent process are grown and sized, and that coarse and irregular particles that are generated during synthesis, such as copper phthalocyanine pigment, are refined and sized in the subsequent process. . Further, the pigment is not particularly limited as long as it is a pigment that requires refinement and sizing, and any conventionally known pigment can be used. For example, in addition to azo pigments, phthalocyanine pigments, and quinacridone pigments, isoindolinone, isoindoline, perylene, perinone, diketopyrrolopyrrole, thioindigo, dioxazine, quinophthalone, anthraquinone, and indanthrone can be used. Two or more kinds of pigments can be mixed and refined.
The water-soluble inorganic salt used in the present invention is not particularly limited, and examples thereof include sodium chloride (sodium chloride), potassium chloride, sodium sulfate, zinc chloride, calcium chloride or a mixture thereof.
As the water-soluble organic solvent used in the present invention, an organic pigment and a water-soluble inorganic salt are added so as to form a uniform mass, and are mixed freely with water, or are not mixed freely but are industrially washed with water. It is not particularly limited as long as the pigment particles grow, but the temperature rises at the time of kneading, and the solvent easily evaporates. preferable. For example, 2- (methoxymethoxy) ethanol, 2-butoxyethanol, 2- (isopentyloxy) ethanol, 2- (hexyloxy) ethanol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol , Triethylene glycol monomethyl ether, liquid polyethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, low molecular weight polypropylene glycol, aniline , Pyridine, tetrahydrofuran, dioxane, methanol, ethanol, isopropyl Nol, n-propanol, isobutanol, n-butanol, ethylene glycol, propylene glycol, propylene glycol glycol monomethyl ether acetate, ethyl acetate, isopropyl acetate, acetone, methyl ethyl ketone, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, etc. Can do. Moreover, you may mix and use 2 or more types of solvents as needed.
The resin used in the present invention is hardly water-soluble and is preferably liquid or solid at room temperature and partially soluble in the water-soluble organic liquid of the present invention. For example, rosin, disproportionated rosin, polymerized rosin, Hydrogenated rosin, rosin ester, rosinamine, maleated rosin, fumarated rosin, rosin metal salts, rosin resins such as rosin modified phenolic resin and rosin modified maleated resin, epoxy resin, acrylic resin, maleic resin, butyral resin, Examples thereof include synthetic resins such as polyester resins, melamine resins, phenol resins, polyurethane resins and polyamide resins, and modified resins derived from fiber and rubber. Rosin resins are particularly preferred from the viewpoint of the effect of addition and cost.
The amount of the water-soluble inorganic salt in the kneaded composition of the present invention is not particularly limited, but is preferably 0.5 to 30 times by weight with respect to the organic pigment. If it is less than 0.5 times by weight, it is difficult to make it fine, and if it is 30 times by weight or more, it becomes possible to obtain a finer pigment. Is disadvantageous.
The amount of the water-soluble organic liquid in the kneaded composition of the present invention is not particularly limited, but is preferably 0.01 to 0.5 times by weight based on the total amount of the organic pigment and the water-soluble inorganic salt. If it is less than 0.01 times by weight, the kneaded composition becomes too hard to be stably operated, and if it is 0.5 times by weight or more, the kneaded composition becomes too soft and the level of refinement is lowered.
The amount of the resin in the kneaded composition of the present invention is not particularly limited, but is preferably 0.001 to 1.0 times by weight with respect to the organic pigment. When the amount is less than 0.001 times by weight, the added effect is hardly obtained, and when the amount is 1.0 by weight or more, the added effect cannot be obtained. Moreover, it is preferable to adjust the amount of the resin according to the difference in properties between the resin and the vehicle resin using the obtained pigment composition. That is, if the difference is large, the amount of resin is kept to the minimum necessary to reduce the effect on the physical properties of the vehicle resin, while if the difference is small, the amount of resin is increased to fully demonstrate the effects of the present invention. It is preferable to make it.
The organic pigment, the water-soluble inorganic salt, the water-soluble organic liquid and the resin, which are constituent materials of the kneading composition of the present invention, may be added to the continuous kneader individually or simultaneously after mixing. Good. Further, a resin may be mixed in the course of the organic pigment production process to form a mixture of the organic pigment and the resin in advance, and in this case, the effect of adding the resin is particularly exhibited.
There are no particular restrictions on the operating conditions of the continuous kneader in the present invention, but organic pigment particle growth by contact with the ground organic pigment particles and the water-soluble organic liquid, and the solubility of the resin in the water-soluble organic liquid. The kneading temperature is preferably 10 to 150 ° C., particularly 40 to 130 ° C., in order to ensure the effective adsorption of the organic pigment to the surface. By increasing the temperature, it is possible to accelerate the growth rate of the pigment particles. In order to control the processing amount and quality of the pigment composition, the blending ratio of the kneaded composition, kneading temperature, mechanical energy input (main shaft (drive shaft 121) rotation speed, raw material supply amount, main shaft power load, etc.) It becomes possible by adjusting When the temperature is higher than 150 ° C., the particle growth is large and it is necessary to shorten the kneading time. After starting the kneading, heating or cooling is performed as necessary. In addition, a raw material charging part is provided in the middle of the continuous kneader to add a resin or a water-soluble organic solvent in the middle of the continuous kneading process to change the blending ratio of the kneading composition, or a plurality of continuous kneaders are connected in series. It is possible to adjust the entire kneading conditions by setting the operating conditions of each continuous kneader separately.
The pigment composition after kneading is treated by a conventional method. That is, the kneaded composition is treated with water or an aqueous mineral acid solution, and the pigment composition is isolated by removing the water-soluble inorganic salt and the water-soluble organic solvent by filtration and washing with water. The pigment composition can be used in a wet state as it is, or in a powder state by drying and pulverization. If necessary, a resin, a surfactant and other additives may be added after kneading.
The pigment composition of the present invention is prepared by preparing extremely fine pigment particles with a small energy with a specific continuous kneader and dispersing them while maintaining the fine pigment particles when used in ink or paint. The pigment particles are refined by adding resin in the process, and at the same time, the pigment particles are coated with the resin to reduce aggregation of the pigment particles, which is suitable for applications that require high transparency. . Therefore, it shows particularly excellent quality for uses such as gravure ink, inkjet ink, and color filter, but also shows excellent quality when used for offset ink, paint, plastic coloring, color toner, and the like. For example, when a gravure ink is prepared, the vehicle to be used is not particularly limited, and may contain an auxiliary agent or extender pigment. As one example, gravure ink vehicles 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, urethane resin, polyester resin, alkyd resin, acrylic resin, gilsonite, dammar, shellac, etc., or a mixture of the above resins or a water-soluble resin obtained by water-solubilizing the above resins, or an emulsion resin And a solvent comprising a solvent such as hydrocarbon, alcohol, ketone, ether alcohol, ether, ester, water, and the like. In particular, it is cellulose-based and has excellent transparency and high gloss and clear quality. In addition, when mixing or dispersing a pigment composition in a vehicle, good mixing or dispersion is performed by using a dissolver, a high speed mixer, a homomixer, a kneader, a flasher, a roll mill, a sand mill, an attritor, etc. Can do.
Hereinafter, the present invention will be described in detail with reference to examples and comparative examples according to conventional methods. However, the present invention is not limited to the scope of these examples. In the examples, “parts” represents parts by weight, and “%” represents% by weight.

100 parts of Blue 15 (T-95 Crude Blue, manufactured by Zhuhai Toyo Co., Ltd.) as an organic pigment, 600 parts of sodium chloride as a water-soluble inorganic salt, 100 parts of diethylene glycol as a water-soluble organic liquid, and rosin ester as a resin (Ester Gum AT, manufactured by Arakawa Chemical Industries) ) Premixed for 5 minutes with a convert mixer (manufactured by Asada Tekko Co., Ltd.) so that 5 parts were almost uniform. This mixture was supplied to a continuous kneader 1 (“Miracle KKK-42 type” manufactured by Asada Tekko Co., Ltd.) with a screw type quantitative feeder (quantitative feeder section 4 (FIG. 1)). The conditions of the continuous kneading machine 1 are: a feed part screw diameter of 120 mmφ, 8 kneading part sets composed of a fixed disk and a rotating disk, an extrusion rate of the kneaded composition of 21 kg / hour, a spindle rotation speed of 50 rpm, and a mixing temperature of 90 ° C. Drove in. The power consumption required for mixing was 1.8 kwh / kg per 1 kg of pigment. The obtained kneaded composition was taken out into 5000 parts of water at 70 ° C., stirred for 1 hour with heat, filtered, washed with water and dried to obtain a pigment composition.
Paint conditioner is mixed with 10 parts of this pigment composition, 90 parts of gravure ink varnish (nitrocellulose resin 12%, ethyl acetate 33%, toluene 30%, isopropyl alcohol 15%, methanol 10%) and 3 mm glass beads 100 parts. The gravure ink prepared by dispersing for 60 minutes was developed on a film with a bar coater. When white paper and black paper were applied to the back side of the color-exposed product and each color was measured with a colorimeter, the difference in lightness L * (ΔL *) was 5.2. ΔL * is often used as a measure of transparency. When ΔL * is large, it indicates that the transparency is excellent.
An example of kneading with a 1000-capacity double-arm kneader conventionally used as a kneader is shown below as Comparative Example 1 and Comparative Example 2. Comparative Example 1 is a case in which a resin having a composition of a normal kneaded product is not included, and Example 1 is a transparency of a gravure ink developed product, although the amount of power consumption is smaller than that of Comparative Example 1. Was excellent. Further, Comparative Example 2 is a case containing a resin with the same composition as Example 1, and Comparative Example 2 is superior to Comparative Example 1 in the transparency of the gravure ink-extended product, and the addition effect of the resin is recognized. Example 1 was superior, and the continuous kneader was superior to the kneader as the kneader.
Examples where the kneaded product does not contain a resin using the continuous kneader of Example 1 as the kneader are shown below as Comparative Example 3 and Comparative Example 4. Comparative Example 3 was the same kneading conditions as Example 1, but the transparency of the gravure ink extended product was inferior, and the effect of adding the resin of Example 1 was recognized. Comparative Example 4 is a case where the amount of the water-soluble organic liquid of Comparative Example 3 is reduced and the power consumption is doubled to increase the kneading energy, but the gravure ink extended product is not much different from Comparative Example 3. The composition of the kneaded product which shows transparency and does not contain a resin has a limit in improving the transparency of the gravure ink extended product.
From the above results, by using a continuous kneader and adding a resin to the kneaded composition, it was possible to obtain a pigment composition excellent in practical quality represented by transparency with less energy. .
[Comparative Example 1] A double-arm kneader having 100 parts by volume of Blue 15 (T-95 Crude Blue, manufactured by Zhuhai Toyo Co., Ltd.) as an organic pigment, 600 parts of sodium chloride as a water-soluble inorganic salt, and 100 parts of diethylene glycol as a water-soluble organic liquid. And kneaded for 5 hours while maintaining a dense lump at 90 ° C. The amount of power consumption required for mixing was 4.1 kwh / kg per 1 kg of pigment. The obtained kneaded composition was taken out into 5000 parts of water at 70 ° C., stirred for 1 hour with heat, filtered, washed with water and dried to obtain a pigment composition. ΔL * of the color-extended product produced from this pigment composition in the same manner as in Example 1 was 1.2.
Comparative Example 2 100 parts of Blue 15 (T-95 Crude Blue, manufactured by Zhuhai Toyo Co., Ltd.) as an organic pigment, 600 parts of sodium chloride as a water-soluble inorganic salt, 100 parts of diethylene glycol as a water-soluble organic liquid, and rosin ester as a resin (Arakawa Chemical Industries) 5 parts of a double-arm kneader having a capacity of 1000 parts by weight was prepared and kneaded for 5 hours at 90 ° C. while maintaining a dense lump (dough). The amount of power consumption required for mixing was 4.1 kwh / kg per 1 kg of pigment. The obtained kneaded composition was taken out into 5000 parts of water at 70 ° C., stirred for 1 hour with heat, filtered, washed with water and dried to obtain a pigment composition. ΔL * of the color-extracted product prepared from this pigment composition in the same manner as in Example 1 was 2.3.
[Comparative Example 3] 100 parts of Blue 15 (T-95 Crude Blue, manufactured by Zhuhai Toyo Co., Ltd.) as an organic pigment, 600 parts of sodium chloride as a water-soluble inorganic salt, and 100 parts of diethylene glycol as a water-soluble organic liquid are almost uniform. The mixture was premixed for 5 minutes (manufactured by Asada Tekko Co., Ltd.) and kneaded and processed in the continuous kneader 1 in the same manner as in Example 1 to obtain a pigment composition. The power consumption required for mixing was 1.8 kwh / kg per 1 kg of pigment, and ΔL * of the color developed product was 3.6.
[Comparative Example 4] 100 parts of Blue15 (T-95 Crude Blue, manufactured by Zhuhai Toyo Co., Ltd.) as an organic pigment, 600 parts of sodium chloride as a water-soluble inorganic salt, and 80 parts of diethylene glycol as a water-soluble organic liquid are almost uniform. The mixture was premixed for 5 minutes (manufactured by Asada Tekko Co., Ltd.) and kneaded and processed in the continuous kneader 1 as in Example 1 to obtain a pigment composition. The amount of extrusion of the kneaded composition at this time was 18 kg / hour, the amount of power consumption required for mixing was 3.6 kwh / kg per 1 kg of pigment, and ΔL * of the color developed product was 3.7.

Example 1 except that the resin was changed to polymerized rosin (Dimalex resin made by Rika Hercules), disproportionated rosin (Longis R made by Arakawa Chemical Industries), and hydrogenated rosin (Stevelite resin made by Rika Hercules) The pigment composition was obtained by kneading and treating in the same manner as described above. Table 1 shows the power consumption required for mixing and ΔL * of the color-extended product.
In any case, compared with Comparative Examples 1 to 4, the color-developed product had a large ΔL * and was excellent in transparency.
[Examples 5 to 7, Comparative Examples 5 to 7] Kneaded under the kneading conditions and the composition of the kneaded material shown in Table 1, and treated in the same manner as in Example 1 to obtain a pigment composition. The organic pigment of Example 5 and Comparative Example 5 is Yellow 138 (Pariotor Yellow K0691HD manufactured by Bassf), the organic pigment of Example 6 and Comparative Example 6 is Red 177 (Chromophthalred A2B manufactured by Ciba Specialty Chemicals), Example 7 and Comparative Violet 23 (Sumiton Fast Violet RL base manufactured by Sumitomo Chemical Co., Ltd.) was used as the organic pigment of Example 7.
In Examples 5 to 7, compared with Comparative Examples 5 to 7, the amount of developed product was large and ΔL * was large and the transparency was excellent with a small amount of power consumption.

It is sectional drawing of the side view which shows one Embodiment of the continuous kneading machine which concerns on this invention. FIG. 2 is a front view or a rear view showing one embodiment of a fixed disk and a rotating disk applied to the continuous kneader shown in FIG. 1, (a) is a cavity fan type fixed disk, and (b) is a cavity fan type rotation. (C) is a cavity chrysanthemum fixed disk, (d) is a cavity chrysanthemum rotary disk, (e) is a cavity mortar fixed disk, and (f) is a cavity mortar rotary disk. .

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Continuous kneading machine 1 Feed part 11 Casing 111 Raw material receiving port 12 Spiral rod 121 Drive shaft 122 Spiral fin 2 Kneading part 21 Fixed disk 21a Cavity fan type fixed disk 21c Cavity chrysanthemum type fixed disk 21e Cavity mortar type fixed disk 211 Free fitting hole 212 Cavity (grinding space)
22 Kneading cylinder 23 Rotating disk 23b Cavity fan type rotating disk 23d Cavity chrysanthemum type rotating disk 23f Cavity mortar type rotating disk 231 External fitting hole 232 Cavity (grinding space)
DESCRIPTION OF SYMBOLS 3 Discharge part 4 Fixed_quantity | feed_rate feeder part 41 Raw material hopper 42 Spiral feeder 43 Connection cylinder 44 Interposition cylinder

Claims (2)

A mixture composed of an organic pigment, a water-soluble inorganic salt, a water-soluble organic liquid, and a resin is formed in a gap portion between an annular fixed disk and the fixed disk that rotates integrally around the axis of the drive shaft and the concentric rotating disk. A method for producing a pigment composition, comprising kneading in a continuous kneader having a pulverizing space. The method for producing a pigment composition according to claim 1, wherein the resin is a rosin resin.

Images