Dust-free phthalocyanine pigments and methods for their preparation
By mixing phthalocyanine pigments with additives and polymers, dust-free phthalocyanine pigments are prepared, solving the problems of dust pollution and poor dispersibility. This enables the production of dust-free, low-cost, and environmentally friendly phthalocyanine pigments, meeting the application needs of coatings and printing inks.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SUNLOUR PIGMENT TAIXING CO LTD
- Filing Date
- 2024-02-23
- Publication Date
- 2026-06-02
Smart Images
Figure BDA0004712860440000081 
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Figure BDA0004712860440000092
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of phthalocyanine pigments, and in particular to a dust-free phthalocyanine pigment and its preparation method. Background Technology
[0002] Phthalocyanine pigments are an important class of organic colorants, widely used in coatings, printing inks, and plastics. Traditional phthalocyanine pigment preparation technology involves turning them into powder pigments, adding additives during the preparation process to modify their performance according to different application requirements, such as adding rosin. The advantages of powder pigments are high effective pigment content (usually greater than 95%), stable storage, and low transportation costs. Their disadvantages include high dust levels. The drying, crushing, and packaging processes during preparation generate significant amounts of dust, and the weighing and pre-dispersion stages in coatings, printing inks, and plastics applications also generate substantial dust. Although current technologies have made significant progress in powder collection, dust pollution remains a problem for manufacturing companies, causing harm to human health and the environment. Furthermore, traditional powder pigments generally suffer from poor dispersibility. Applications in coatings, printing inks, and plastics require strong mechanical force and prolonged grinding and dispersion; otherwise, the pigment's coloring performance cannot be fully realized, resulting not only in dust pollution but also increased processing costs for downstream users, unstable product quality, and poor application results.
[0003] To address the aforementioned issues, many clean pigment products have been researched, but these are not powder pigments; rather, they are pigment preparations with low effective pigment content, such as masterbatches and color pastes. Masterbatches are prepared by melting powder pigments with resin at high temperatures, kneading, and then extruding, stretching, and granulating to obtain granular coloring pigments. While masterbatches solve the problems of pigment dust and dispersibility, their effective pigment content is low, typically not exceeding 40%, and they are also troubled by powder pigment dust during the initial metering and mixing process with resin. Color pastes are made by mixing powder pigments with water and additives, grinding them to a certain fineness using a sand mill, and then packaging and selling them; their effective pigment content is not higher than 35%. Both color pastes and masterbatches require the construction of new factories and the purchase of specialized equipment to establish new production sites, increasing production costs; the low effective pigment content increases transportation and storage costs; and they are also troubled by pigment dust during the initial metering and mixing process.
[0004] Therefore, it is urgent to develop a preparation process to directly produce dust-free phthalocyanine pigments and fundamentally solve the problems of dust pollution and dispersibility of organic pigments. Summary of the Invention
[0005] To address the shortcomings of existing technologies, this application provides a dust-free phthalocyanine pigment and its preparation method.
[0006] In the first aspect, this application provides a dust-free phthalocyanine pigment, which adopts the following technical solution:
[0007] A dust-free phthalocyanine pigment, comprising the following raw materials in parts by weight: 80-100 parts phthalocyanine pigment, 5-15 parts nonionic and anionic additives, 5-10 parts anionic treatment agent, 5-10 parts calcium chloride, and 1-10 parts polymer.
[0008] In this application, phthalocyanine pigment, nonionic and anionic additives, and anionic treatment agents are mixed and fully wetted and dispersed to adsorb onto the surface of the phthalocyanine pigment. Calcium chloride is added to stably deposit and coat the highly hydrophilic anionic additives onto the pigment surface. A polymer is further added to flocculate the coated pigment from the aqueous dispersion, while the polymer further coats the pigment ions. After filtration and protective drying, dust-free phthalocyanine pigment is obtained.
[0009] Preferably, the anionic treatment agent is one or both of maleic rosin and styrene-maleic anhydride polymer.
[0010] Preferably, the polymer is one or both of cationic polyacrylamide and polyethylene glycol.
[0011] Preferably, nonionic and anionic additives include nonionic surfactants and anionic surfactants.
[0012] Preferably, the mass ratio of nonionic surfactant to anionic surfactant is 1:(1-10).
[0013] Preferably, the nonionic surfactant is at least one of fatty alcohol polyoxyethylene ether surfactants, fatty amine polyoxyethylene ether surfactants, fatty acid polyoxyethylene ether surfactants, and oleic acid ester surfactants.
[0014] More preferably, the nonionic surfactants are fatty alcohol polyoxyethylene ether surfactants (AEO series), fatty amine polyoxyethylene ether surfactants (AC series), fatty acid polyoxyethylene ether surfactants (EL series), and oleic acid ester surfactants (SPAN series), corresponding to commercially available products such as emulsifier AE0, such as AE0-10, AE0-15, etc.; emulsifier AC series, such as AC-1205, AC-1210, etc.; emulsifier EL series, such as emulsifier EL-20, EL-40, EL-60; and emulsifier SPAN series, such as emulsifier span-20, span-40, span-60, span-80, etc.
[0015] Preferably, the anionic surfactant is Turkish red oil.
[0016] The phthalocyanine pigments in this application are phthalocyanine pigments with a phthalocyanine main structure, including but not limited to copper phthalocyanine (phthalocyanine blue 15:0, phthalocyanine blue 15:1, phthalocyanine blue 15:2, phthalocyanine blue 15:3, phthalocyanine blue 15:4, phthalocyanine blue 15:5, phthalocyanine blue 15:6), zinc phthalocyanine, aluminum chloride phthalocyanine, iron phthalocyanine, cobalt phthalocyanine, etc.
[0017] This application discloses a method for preparing dust-free phthalocyanine pigment. The method involves adding nonionic and anionic additives and anionic treatment agents to a phthalocyanine pigment filter cake, dispersing them thoroughly, then adding calcium chloride to deposit the treatment agent onto the surface of the phthalocyanine pigment. A polymer is then added to flocculate the coated pigment from the aqueous suspension, separating it, and then protectively drying it to obtain phthalocyanine pigment powder aggregates (i.e., dust-free phthalocyanine pigment). These aggregates have a loose structure, require no further pulverization, and are dust-free during packaging and application.
[0018] Secondly, this application provides a method for preparing dust-free phthalocyanine pigments, employing the following technical solution:
[0019] A method for preparing a dust-free phthalocyanine pigment includes the following steps: phthalocyanine pigment, deionized water, nonionic and anionic additives, and anionic treatment agent are mixed and pulped until the particles are uniformly dispersed. Then, calcium chloride and a polymer are added and reacted. Finally, the mixture is dried using a vacuum drying method to obtain the dust-free phthalocyanine pigment.
[0020] Preferably, the pulping time is 1-4 hours.
[0021] Preferably, the mass ratio of phthalocyanine pigment to deionized water is 1:(8-10).
[0022] In this application, nonionic and anionic additives and anionic treatment agents are added to a wet filter cake (phthalocyanine pigment filter cake) under water protection to fully disperse the pigment into very small particles. Then, calcium chloride is used for calcification, and the hydrophilic anionic additive is deposited on the pigment surface to protect the small particles, forming an aqueous suspension. A polymer is then added to flocculate the coated pigment from the aqueous suspension, while the polymer further coats the pigment particles. After standing, the pigment and water are clearly separated. The filtered water is then washed simply and then dried protectively to obtain phthalocyanine pigment powder aggregates.
[0023] Although the pigment particles themselves are very small, they are coated with many additives on their surface, preventing aggregation during drying and resulting in good dispersibility. Therefore, vigorous grinding is not required for application. This application employs a vacuum drying method to avoid secondary aggregation during the drying process.
[0024] The preparation technology described in this application is universal and can be applied to the preparation process of other pigments to obtain a series of dust-free powder pigments.
[0025] In summary, this application includes at least one of the following beneficial technical effects:
[0026] 1. The present application discloses a dust-free phthalocyanine pigment and its preparation method, which produces no dust during packaging and application, thus fully protecting human health and environmental cleanliness.
[0027] 2. The dust-free phthalocyanine pigment and its preparation method disclosed in this application have excellent wetting and dispersibility and can be fully dispersed in the application medium. Detailed Implementation
[0028] The phthalocyanine pigments in this application are phthalocyanine pigments with a phthalocyanine main structure, including but not limited to copper phthalocyanine, zinc phthalocyanine, aluminum chloride phthalocyanine, iron phthalocyanine, cobalt phthalocyanine, etc. In this embodiment, copper phthalocyanine (phthalocyanine blue 15:3) is used as an example for illustration.
[0029] All raw materials involved in this application are commercially available products, including:
[0030] Copper phthalocyanine (phthalocyanine blue 15:3) raw material filter cake, solid content 35%, manufacturer: Shuangle Pigment Co., Ltd.
[0031] The molecular weight of styrene-maleic anhydride polymer is 7500-10000.
[0032] The molecular weight of cationic polyacrylamide is 8-12 million.
[0033] The molecular weight of polyethylene glycol is 190-840.
[0034] The present application will be further described in detail below with reference to embodiments and comparative examples.
[0035] Example 1:
[0036] 700g of deionized water, 2g of emulsifier EL-400, 4g of turquoise oil, and 8g of rosin were added to 286g of phthalocyanine pigment (phthalocyanine blue 15:3) filter cake with a solid content of 35% to prepare an aqueous solution. The solution was stirred for 2 hours to form a uniform aqueous suspension. High-speed dispersion was continued, and microscopic examination was performed until the crystal size was uniform and no large aggregates were present. 8g of calcium chloride was added to prepare an aqueous solution, and the mixture was stirred for 30 minutes. 2g of cationic polyacrylamide (CPAM) was added, and the mixture was stirred until the suspension separated into layers. The separated water was poured off, and the viscous pigment paste was placed in a vacuum drying oven and dried under vacuum at 50°C to obtain approximately 116g of dust-free phthalocyanine blue 15:3 pigment aggregates.
[0037] Example 2:
[0038] The difference between this embodiment and Embodiment 1 is that the amount of Malaysian rosin added is 5 grams.
[0039] Example 3:
[0040] The difference between this embodiment and Embodiment 1 is that the amount of Malaysian rosin added is 10 grams.
[0041] Example 4:
[0042] 700g of deionized water, 3g of emulsifier Span-200, 3g of turquoise oil, and 8g of rosin were added to 286g of phthalocyanine pigment (phthalocyanine blue 15:3) filter cake with a solid content of 35% to prepare an aqueous solution. The solution was stirred for 2 hours to form a uniform aqueous suspension. High-speed dispersion was continued, and microscopic examination was performed until the crystal size was uniform and no large aggregates were present. 8g of calcium chloride aqueous solution was added and stirred for 30 minutes. 4g of cationic polyacrylamide (CPAM) was added and stirred until the suspension separated into layers. The separated water was poured off, and the viscous pigment paste was placed in a vacuum drying oven and dried under vacuum at 50°C to obtain approximately 118g of dust-free phthalocyanine blue 15:3 pigment aggregates.
[0043] Example 5:
[0044] 700g of deionized water, 53g of emulsifier AC-120, 4g of turquoise oil, and 5g of rosin were added to 286g of phthalocyanine pigment (phthalocyanine blue 15:3) filter cake with a solid content of 35% to prepare an aqueous solution. The solution was stirred for 3 hours to form a uniform aqueous suspension. High-speed dispersion was continued, and microscopic examination was performed until the crystal size was uniform and no large aggregates were present. 8g of calcium chloride aqueous solution was added and stirred for 30 minutes. 6g of cationic polyacrylamide (CPAM) was added and stirred until the suspension separated into layers. The separated water was poured off, and the viscous pigment paste was placed in a vacuum drying oven and dried under vacuum at 50°C to obtain approximately 129g of dust-free phthalocyanine blue 15:3 pigment aggregates.
[0045] Example 6:
[0046] 700g of deionized water, 2g of emulsifier AEO-102g, 3g of turquoise oil, and 8g of anion exchange agent were added to 286g of phthalocyanine pigment (phthalocyanine blue 15:3) filter cake with a solid content of 35% to prepare an aqueous solution. The solution was stirred for 2 hours to form a uniform aqueous suspension. High-speed dispersion was continued, and microscopic examination was performed until the crystal size was uniform and no large aggregates were present. 8g of calcium chloride aqueous solution was added, and the mixture was stirred for 30 minutes. Then, 10g of polymer was added, and the mixture was stirred until the suspension separated into layers. The separated water was poured off, and the viscous pigment paste was placed in a vacuum drying oven and dried at 50°C to obtain approximately 123g of dust-free phthalocyanine pigment aggregates.
[0047] The anionic treatment agent is a mixture of 5 grams of maleic rosin and 3 grams of styrene-maleic anhydride polymer. The polymer is a mixture of 5 grams of cationic polyacrylamide (CPAM) and 5 grams of polyethylene glycol. Comparative example:
[0048] Comparative Example 1:
[0049] The difference between this comparative example and Example 1 is that the emulsifier EL-40 is not added.
[0050] Using the method described in this comparative example, the prepared product will have large particles, poor dispersibility, and relatively hard particles.
[0051] Comparative Example 2:
[0052] The difference between this comparative example and Example 1 is that Turkish red oil is not added.
[0053] Using the method in this comparative example, the prepared product has poor dispersibility and produces large, hard particles.
[0054] Comparative Example 3:
[0055] The difference between this comparative example and Example 1 is that no rosin is added.
[0056] Using the method described in this comparative example, it is impossible to coat the particles during the preparation process, resulting in harder particles.
[0057] Comparative Example 4:
[0058] The difference between this comparative example and Example 1 is that calcium chloride is not added.
[0059] Using the method described in this comparative example, pigment separation is difficult, making it impossible to prepare a shaped product.
[0060] Comparative Example 5:
[0061] The difference between this comparative example and Example 1 is that cationic polyacrylamide (CPAM) is not added.
[0062] Using the method described in this comparative example, loose aggregates cannot be formed, making filtration difficult and resulting in dust in the dried product.
[0063] Application example:
[0064] Application Example 1: Pigment Dust Detection
[0065] Weigh 50 grams of the dust-free phthalocyanine pigment aggregates prepared in Examples 1-6 and place them on a weighing sheet. Pour the aggregates into a beaker from a height of 50 cm above the rim and observe the dust situation. Almost no dust was observed. As a comparison, the same procedure was performed on a commercially available powder pigment (phthalocyanine blue 15:3). Visually, a large amount of dust was observed, and dust adhered to the surrounding work surface and the experimenter's arm.
[0066] Application Example 2: Performance Testing
[0067] The performance of the dust-free phthalocyanine pigments (i.e., dust-free phthalocyanine pigment aggregates) prepared in Examples 1-6 was tested:
[0068] Product appearance: visual inspection;
[0069] Color detection: The color was determined according to GB / T9761-98 "Visual colorimetry of paints and varnishes".
[0070] Tinting strength test: The test was conducted in accordance with GB / T 13451.2-92 "Determination of relative tinting strength of color pigments and relative scattering strength of white pigments".
[0071] The dust-free phthalocyanine pigment aggregates prepared in Examples 1-6 were tested using the above method, and the results are as follows:
[0072] Table 1 Performance Test Results
[0073]
[0074]
[0075] Among them, the loose aggregates defined in Table 1 are coarse, amorphous particles, which, when gently pressed with a finger, appear as fine powder.
[0076] According to the data in Table 1, the dust-free phthalocyanine pigments prepared in Examples 1-6 have similar coloring properties to commercially available copper phthalocyanine (phthalocyanine blue 15:3), which meets the requirements for commercial production. This indicates that the dust-free phthalocyanine pigments prepared in this application still exhibit good coloring power even with low effective content, and the color change is not significant, which meets the requirements for commercial products.
[0077] The dust-free phthalocyanine pigment (effective content of 86.2%) prepared in Example 1 has a coloring strength comparable to that of commercially available products (effective content of 95%), indicating that the preparation method of this application can effectively improve the coloring strength of the pigment.
[0078] Application Example 3: Bulk Density Detection
[0079] The dust-free phthalocyanine pigment aggregates prepared in Examples 1-6 and the traditional powder pigment (phthalocyanine blue 15:3) were tested. The testing procedure was as follows: 50 grams of sample were weighed and placed in a 250 ml graduated cylinder, which was shaken up and down 25 times, and the volume was measured. The results showed that the dust-free phthalocyanine pigment aggregates prepared in Examples 1-6 had a lower bulk density than the traditional powder pigment (phthalocyanine blue 15:3). The test results are shown in Table 2.
[0080] Table 2 Bulk Density Detection
[0081]
[0082]
[0083] As shown in Table 2, the bulk density test results of Examples 1-6 are better than those of commercially available copper phthalocyanine (phthalocyanine blue 15:3), indicating that the bulk density of the product has been effectively improved by the improvement of raw materials and preparation methods in this application.
[0084] Application Example 4: Dispersion Comparison Test
[0085] Comparison sample: Commercially available phthalocyanine blue 15:3 (product of Jiangsu Shuangle Pigment Co., Ltd.);
[0086] Samples: Samples obtained in Examples 1 to 6;
[0087] Experimental equipment: High-speed disperser (model SFJ-400);
[0088] Test method:
[0089] Weigh 100 grams of commercially available alkyd enamel, add 2 grams of sample, stir at low speed until uniform, increase the stirring speed to 2800 rpm and stir at high speed. Take samples at 10 minutes, 20 minutes, 30 minutes and 60 minutes respectively, scrape them on scraper paper, and visually observe the change in the depth of the scraped sample before and after sampling to determine its dispersibility.
[0090] Table 3 Dispersion test results
[0091]
[0092]
[0093] As shown in Table 3, the sample prepared in this application can be completely dispersed after 45 minutes of high-speed stirring at 1200 rpm. Extending the stirring time does not improve the color intensity, as shown in the samples of Example 1 and Example 6. This indicates that the dispersibility of the pigment obtained by the preparation method of this application is significantly improved compared with the comparative sample.
[0094] The dust-free phthalocyanine pigment disclosed in this invention is a loosely structured aggregate of phthalocyanine pigment powder with an effective pigment content of 80-95% and a tinting strength of 95%-100% of that of conventional pigments. It exhibits excellent wetting and dispersibility in aqueous or solvent-based application media, requiring only simple mechanical stirring to fully disperse in the application medium. It also demonstrates good storage stability in the application medium, meeting the coloring requirements of printing inks and coatings. Furthermore, the dust-free pigment involved in this invention is characterized by being dust-free during packaging and application, thus fully protecting human health and environmental cleanliness.
[0095] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.
Claims
1. A method for preparing a dust-free phthalocyanine pigment, characterized in that, The preparation steps are as follows: After mixing phthalocyanine pigment, deionized water, nonionic and anionic additives, and anionic treatment agent, the mixture is slurryed until the particles are evenly dispersed. Calcium chloride is added and stirred. Then, a polymer is added and stirred until the suspension separates into layers. The separated water is poured off, and the viscous pigment paste is dried using a vacuum drying method to obtain dust-free phthalocyanine pigment. The dust-free phthalocyanine pigment comprises the following raw materials in parts by weight: 80-100 parts phthalocyanine pigment, 5-15 parts nonionic and anionic additives, 5-10 parts anionic treatment agent, 5-10 parts calcium chloride, and 1-10 parts polymer. The anionic treatment agent is one or both of maleic rosin and styrene-maleic anhydride polymer; The polymer is one or both of cationic polyacrylamide and polyethylene glycol; Nonionic and anionic additives include nonionic surfactants and anionic surfactants; The nonionic surfactant is at least one of the following: fatty alcohol polyoxyethylene ether surfactant, fatty amine polyoxyethylene ether surfactant, fatty acid polyoxyethylene ether surfactant, and oleic acid ester surfactant; The anionic surfactant is Turkish red oil; The mass ratio of nonionic surfactant to anionic surfactant is 1:(1-10).
2. The method for preparing a dust-free phthalocyanine pigment according to claim 1, characterized in that: The pulping time is 1-4 hours.
3. The method for preparing a dust-free phthalocyanine pigment according to claim 1, characterized in that: The mass ratio of phthalocyanine pigment to deionized water is 1:(8-10).