JPH0374706B2 - - Google Patents

Description

[Detailed description of the invention]

Technical Field of the Invention The present invention mainly relates to a method for continuously producing a phthalocyanine pigment dispersion material having a β-crystalline structure, and more specifically to a method for continuously producing a phthalocyanine blue pigment in a binder containing an organic solvent. Regarding the method. DESCRIPTION OF THE PRIOR ART The phthalocyanine blue pigments produced according to the present invention may be used in pasty printing inks, solvent-based inks and paints. In the production of crude phthalocyanine pigments, products containing impurities of relatively large crystal size are generally formed, and crude phthalocyanine pigments are conventionally referred to in the art as crude phthalos. . Such crude phthalos require particle size reduction and/or purification by some means to render them useful as pigments of the necessary color strength for use in compositions such as printing inks and paints. Various methods have been proposed to reduce the particle size or improve the purity of crude phthalo. The use of aqueous media to grind crude phthalos is disclosed in US Pat. No. 2,999,862.
U.S. Pat. No. 3,775,149 is also concerned with making phthalocyanine pigments, sometimes by dissolving crude phthalos in water in the presence of a surfactant to produce a filterable paste of phthalocyanine, which is primarily of beta crystal structure. It is related to grinding in a liquid suspension. However, in this process agglomerates are formed and the pigments are purified when they are recovered as a presscake or in dry form. Pigment agglomeration was thus a desirable feature in these prior methods, providing a means to purify the pigment. However, the presscake or dry pigments thus obtained must be redispersed when used in products such as inks, paints, and paints. U.S. patent application filed April 26, 1979
No. 033362 describes in detail a method for continuously producing a water-soluble phthalocyanine pigment dispersion. The inventors of the present application have been able to produce phthalocyanine pigments with a β-crystalline structure in a continuous manner in a binder containing an organic solvent, and the pigments thus produced can be used in oil-based paste inks and organic It has been found that it can be used directly in solvent-based products such as paints.
The pigment dispersion in an organic solvent produced by the method of the present invention allows two steps in the use of phthalocyanine blue pigments: filtering the agglomerated pigment and dispersing the pigment for final use. The process of re-dispersing becomes unnecessary. SUMMARY OF THE INVENTION The present invention relates to a two-step continuous process for converting crude phthalocyanine into a dispersed state in an organic solvent useful in oil-based pasty inks and organic coatings. , (A) about 5 to 20 wt% surfactant based on pigment and 10 to 20 wt% crude phthalo concentration based on the total mixture.
A pre-mixing step in which the crude phthalo is premixed with a sufficient amount of binder (contained in an organic solvent) to reduce the coarse phthalo to 50 wt%, resulting in a loose and wet mass without reducing the particle size of the crude phthalo too much. (B) reducing the size of the coarse phthalo to a size where the pigment dispersant has a color strength suitable for use in inks and paints; At the flow rate obtained, the mixture of step (A) is passed continuously through at least one, preferably two, series shot mills containing 50 to 90 vol% of grinding media having a size in the range of about 0.1 to 2.5 mm in diameter. It includes the process and . More specifically, the present invention provides a continuous process for producing phthalocyanine blue pigment dispersions in organic solvents. This method consists of: (A) a surfactant of 5 to 20 wt% based on the pigment and a concentration of crude phthalo of 10 to 20 wt% based on the entire mixture;
A premixing step in which the crude phthalo is premixed with a sufficient amount of binder (contained in an organic solvent) to reduce the crude phthalo to a loose mass without reducing the particle size of the crude phthalo too much. (B) a pre-mixing step carried out by stirring to obtain a homogeneous mixture of ingredients;
grinding the mixture of step (A) continuously in at least one, preferably two, series shot mills containing 90 vol% grinding media at a flow rate capable of reducing the coarse phthalo particle size to the pigment particle size; , contains. As used herein, crude phthalocyanine refers to crude phthalocyanine pigments obtained commercially by various syntheses, including copper phthalocyanine, cobalt phthalocyanine, zinc phthalocyanine, nickel phthalocyanine, cadmium phthalocyanine, and metal-free phthalocyanine. Contains. Of these, copper phthalocyanine is particularly preferred because of its known commercial value in inks and coatings. Coarse phthalo generally contains at least 80% of the coarse phthalo particles.
The particle size is such that it has a size of 1μ or more. After the crude phthalo is converted into a dispersed state according to the method of the invention, at least 95% of the pigment particles
have been found to have dimensions of less than 1 micron, this dimension is referred to herein as the pigment particle size. Particle size measurements are suitably made using a Sedigraph 500 particle size analyzer. As used herein, pigment particle size refers to a particle size such that the treated crude phthalo dispersion has a color strength suitable for use in inks and coatings. Color intensity is the color of one pigment mixed with a specific amount of white base (batch pigment) compared to the color of another pigment mixed with an equal amount of the same white base (standard pigment).
It is measured appropriately by comparing the color with that of
Although the amounts of standard pigments and batch pigments are identical in terms of their shade, these pigments exhibit different colors from each other if they differ in their particle size and, therefore, in their color intensity. A batch pigment is considered more intense than a standard pigment if the color of the batch pigment appears to be generated by a larger amount of pigment than the color of the standard pigment. Using such a procedure, the color strength of the unmilled crude phthalo is very low or virtually zero, whereas the color strength of the crude pigment dispersion produced according to the present invention differs from that of the original crude pigment. (100
It turned out to be about twice as high. In one preferred embodiment, the present invention is directed to a method for converting blister copper phthalocyanine pigments having at least 80% of the particle size greater than or equal to 1 micron into a dispersed state useful in inks and coatings, the method comprising: (A) pre-containing a binder (contained in an organic solvent) and coarse pigment in an amount sufficient to reduce the concentration of about 5 to 20 wt% surfactant and coarse pigment to 10 to 50 wt% based on the total mixture; (B) a premixing step which is carried out by stirring to break up the loose agglomerations of the pigment and obtain a homogeneous mixture of the components without reducing the particle size of the coarse pigment too much; 50 with sizes ranging from 0.1 to 2.5mm
at least one containing ~90vol% grinding media,
Preferably two shot mills in series (A)
pulverizing the mixture at a flow rate capable of producing a dispersion having a color strength suitable for use in inks and paints. Surfactants useful in the method of the invention include solid surfactants and solvent-soluble nonionic and cationic solution type surfactants. However, only a limited number of compounds in each class are effective dispersoids. The surfactant used in the method of the invention must meet the following criteria in order to be effective. (A) The concentration of surfactant relative to the coarse pigment must be such that the entire surface of the crushed coarse pigment is covered with a monomolecular layer of surfactant. (B) The surfactant is applied only up to the desired concentration level;
In other words, it must be only partially soluble in the solvent. A solid surfactant useful in the method of the invention can be represented as a fatty acid amine salt of sulfonic acid phthalocyanine blue. Product name Chemical name Toyo 103 Fatty acid amine salt of phthaloblue sulfonate Solsperse 5000 〃 Inmont 2741 〃 BT 417D Phthaloblue sulfonate Nonionic surfactants are generally indicated as ethylene oxide adducts, and cationic surfactants are quaternary surfactants. Ammonium salts and amines are indicated; anionic surfactants are indicated as acid salts. Particular solution-based surfactants that have been found to be suitable include:

TABLE ON Raylamine Typical useful surfactant concentration levels have been found to be about 5-20 wt% based on crude phthalocyanine. Such surfactant concentration levels are an important aspect of the present invention, as they allow for reduced grinding times, i.e., higher flow rates through the mill, and that the final diluted Crude phthalocyanine can be ground to much smaller particle sizes without pigment agglomeration occurring in the composition. It is very important that no agglomeration occurs according to the method of the invention, and therefore the selection of the surfactant and its concentration are important aspects of the method of the invention. The process of the invention is preferably carried out at temperatures of about 5 DEG to 80 DEG C., and is fully functional at room temperature. However, since heat is generated during the grinding process at any temperature, cooling is necessary if the mixture needs to be maintained at ambient temperature. The temperature of the mixture may be increased to some extent, for example up to 80°C, in order to save on cooling costs, without any harmful effects, but the temperature of the grinding should in no case exceed 90°C. Preferably, it does not increase. Wetting (premixing) of the crude phthalo (step A) in the process of the invention may be carried out in any type of mixing vessel or shot mill. The mixture is stirred to form a homogeneous crude product. The mixture is then passed through at least one, preferably two, pressurized shot mills capable of containing grinding media of glass, steel, ceramic, etc., with dimensions ranging from 0.1 to 2.5 mm in diameter. The flow rate for feeding the mixture to 25 shot mills is 50-1000 lb/hr (22.7-45 Kg/hr),
Most preferably 100-250lb/hr (45.4-113Kg/
hr) may be varied within the range of hr). The mixture is passed through at least two shot mills to bring the pigment and color strength to levels suitable for commercial use. Pigment particle size can be varied by varying the residence time in the shot mill;
One or more shot mills may be used in the grinding process. It has been found that by using at least two shot mills, the time and power consumption can be optimized to form a pigment dispersion having the color strength desired for commercial applications. Pigment dispersions prepared in accordance with the present invention may be used to color a variety of solvent- or oil-based inks and paints. Typically, inks made according to the present invention include pigments dispersed in a resin solution. Such inks may contain other conventional ink components. For example, ethylcellulose, wax compounds, pigment wetting agents, reactive hydrocarbon resins, etc. may be added according to their known effects. The invention will now be described with reference to specific examples. In these examples, as elsewhere in this specification, all amounts and proportions are expressed as parts by weight unless otherwise indicated. DESCRIPTION OF THE PREFERRED EMBODIMENTS Throughout this specification, all parts are to be understood as parts by weight. The invention will now be described with reference to the following examples. Example 1 Production of a solvent-based phthalo blue dispersion by milling for 100 hours in a Jar mill. Blended copper phthalo blue (Toyo #4) 15.0 Sulfonic acid phthalocyanine induced retention 0.6 Resin binder (zinc acid rosin) 21.9 Octylphenoxy polyethoxyethanol (Triton X-15) 0.3 Solvent (lactol spirit) 112.2 0.75 mm glass powder 200.0 The resulting phthalo blue pigment grind was found to have a color intensity equivalent to standard pigments and the like when it was formed into an ink for magazine gravure printing. Example 2 The following materials were added to a 150 gallon (568) tank. Blended Copper Phthalo Blue (Toyo #4) 19.0 Sulfonic Acid Phthalocyanine Derivative (2741) 1.0 Resin Binder (Zinc Acid Rosin) 33.0 Solvent (Lactol Spirit) 47.0 These materials were mixed in a tank until a homogeneous mixture was obtained. The resulting mixture was then milled in a 25 Drais horizontal disc mill for a total of three passes at a flow rate of 150 lb/hr (68 Kg/hr) per pass. In this case the mill contained an 85vol% carbon steel shot with a diameter of 0.25mm. The resulting phthalo blue pigment dispersion was found to have superior blue properties compared to standard dispersions and was used directly in the formation of magazine gravure printing inks without agglomeration. Example 3 A procedure identical to that of the example above was followed, except that the following materials were added to a 150-gallon (568) tank. Blister Copper Phthalo Blue (Toyo #4) 20.0 Lecithin 2.0 Lactol Spirit 78.0 When the grinding is completed, which is carried out at a flow rate of 150 lb/hr (68 Kg/hr), the pigment will agglomerate during the formation of magazine gravure printing ink and thus the pigment It was not useful as a dispersion material. Example 4 A procedure identical to that of Example 2 above was followed except that the following materials were added to a 150 gallon (568) tank. Blended copper phthalo blue (Toyo #4) 16.0 Sulfonic acid phthalocyanine derivative (Toyo 103)
0.8 Treated Phthalo Blue Pigment (Du Pont BT
4171) 1.2 Bis(2-hydroxyethyl)oleylamine (E thomeen 0/12) 0.2 Resin binder (rosin zincate) 32.1 Solvent (lactol spirit) 49.7 These materials are mixed in a tank until a homogeneous mixture is obtained. It was done. The mixture is then passed at a flow rate of 95-150 lb/hr (43-68 Kg/hr) per pass.
Milled over a total of two passes in a Drais horizontal disc mill. In this case, the mill has a diameter of 0.25 mm.
Contained 85vol% steel shot. The dispersion of phthalo blue pigment thus obtained was found to have excellent blue color properties and was used directly in the formation of inks for magazine gravure printing. Example 5 The following materials were added to a 10 gallon (37.9) tank. Blended copper phthalo blue (Toyo #4) 34.0 Sulfonic acid phthalocyanine derivative (Solsperse
5000) 1.7 Solsperse 3000 (proprietary) Rosin Maleic Modified PE Ester (Pentalyn G) 5.88 Alkyd (K882) 5.88 Hydrocarbon Solvent (470 Oil) 8.69 Tridecyl Alcohol 1.4 Antioxidant (I onol-Shell) 0.15 Solvent (Lactol Spirit) 40.3 These materials were mixed in a tank until a homogeneous compound was obtained. The resulting mixture was milled in a 4 Netzsch horizontal disc shot mill for a total of three passes at a flow rate of 20 lb/hr (9 Kg/hr) per pass. In this case the mill contained a 90vol% steel shot with a diameter of 0.45mm. The dispersion material thus formed was used directly to form an ink for gravure printing of magazines. Example 6 Lactol spirit is a hydrocarbon medium
The same procedure as in Example 5 above was followed, except that 470 Magie Oil was substituted. The dispersion thus obtained was used in oil-based inks for letter printing and thermoset web offset printing. Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited to these embodiments, and various embodiments are possible within the scope of the present invention. will be clear to those skilled in the art.

Claims (1)

[Scope of Claims] 1. β from a crude phthalocyanine, in which at least 80% of the coarse particles have a particle size of 1 μm or more, into a dispersion state useful for inks and paints.
- A method for producing a dispersion material of phthalocyanine pigment, comprising: (a) crude phthalocyanine in an amount of 5 to
Sulfonic acid phthalocyanine with a concentration of 20wt%.
A solid surfactant, such as a blue fatty acid amine salt, or a nonionic or cationic solution-based surfactant, and a binder in an amount sufficient to reduce the concentration of crude phthalocyanine to 10-50 wt% of the total mixture. a premixing step in which the crude phthalocyanine is premixed with an organic solvent containing the crude phthalocyanine to such an extent that loose clumps of the crude phthalocyanine can be broken down and a homogeneous mixture of the crude phthalocyanine can be obtained without reducing the particle size of the crude phthalocyanine too much. (b) following step (a), grinding the mixture obtained in step (a), the grinding step comprising a grinding medium having a size of 0.1 to 2.5 mm; 50～
pulverizing the mixture obtained in step (a) through at least one, preferably two shot mills containing only 90 vol. % crude phthalocyanine until the particle size is such that it can be used as a pigment. β from the crude phthalocyanine
- A method for producing a phthalocyanine pigment dispersion.