An aqueous color masterbatch composition containing aluminum powder pigments

Abstract

The application discloses an aqueous color masterbatch composition containing aluminum powder pigments, which comprises, by weight parts, 10-50 parts of mixed resins, 4-12 parts of aluminum powder pigments, 0.8-6 parts of aluminum powder pigment wrapping protective agents, 0.01-5 parts of anti-rust pigments, 1-12 parts of auxiliary agents, 3-10 parts of solvents, 15-50 parts of deionized water, and the total weight of the above components is 100 parts. The aqueous color masterbatch composition containing aluminum powder pigments improves the blackening and blistering problems of the aluminum powder pigments in the aqueous coating, has high stability, metallic luster and brightness, and meets the common needs of the automobile repair paint industry for aqueous environmental protection and excellent appearance. The application also relates to a preparation method of the aqueous color masterbatch composition containing aluminum powder pigments.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of coating technology, in particular, to a coating composition related to automotive refinish, especially a waterborne topcoat composition and a waterborne basecoat composition containing aluminum powder pigments in a multi-layer waterborne refinish paint, and a preparation method of the above-mentioned compositions. BACKGROUND

[0002] Due to reasons such as accident damage or natural aging, the outer coating of a car needs to be partially repaired or repainted, which is also called automotive repair. Under the promotion of domestic environmental protection policy and international coating technology development, waterborne automotive refinish paint has developed rapidly. Waterborne refinish paint is almost 100% used in western European countries through laws and regulations, and the conversion rate of waterborne paint in North American countries has reached more than 40%. Although the market share of waterborne paint in Asia is lower than that in Europe and the United States, its growth is rapid, especially in the Chinese market, the growth rate of waterborne paint has led the world, and it is expected to become the world's most important waterborne refinish paint market in the future.

[0003] Automotive refinish paint products usually include a large product series, such as a primer product series to protect the substrate from rust, a midcoat paint product series to improve flatness and stone chip resistance, a color basecoat paint series to provide color appearance effects, and a clearcoat product series to provide gloss and fullness, etc. dozens or even hundreds of color basecoat and auxiliary products. In actual repair work, the color formula needs to be obtained from the formula platform according to different repair colors, then the color is adjusted by adding color basecoat according to the recommended formula, and finally the necessary auxiliary materials are added to complete the spraying work. Therefore, for refinish paint products, the stability of the product, especially the stability of the color basecoat composition, is crucial. Any color deviation of the color basecoat will cause color error of the entire color matching system, ultimately affecting the delivery of the product and the satisfaction of the customer.

[0004] In commercial automotive coatings, metallic paint accounts for a high market share, especially aluminum powder as the main metal pigment is widely used in waterborne coatings. Due to the instability of aluminum powder in water, the aluminum powder in the pigment will slowly react with water to release hydrogen, which will also cause the aluminum powder pigment to gradually turn black and lose the metallic luster. At the same time, due to the shelf life of automotive refinish paint products is usually much longer than other conventional waterborne paint products (usually more than 2 years), which also poses a great challenge to the safety of sealed waterborne refinish paint and the long-term stability of the coating product.

[0005] In the prior art, there are several solutions to solve the stability problem of aluminum powder in the aqueous system. For example, patent US5151125 proposes an aqueous coating composition containing aluminum powder, which is copolymerized by unsaturated monomers and phosphate ester monomers. Although it can reduce the gas evolution of aluminum powder, it has limited effect on improving the gas evolution stability of aluminum powder. Patent EP0170474 introduces a method for wrapping aluminum powder with an epoxy-containing phosphoric acid polymer to improve the gas evolution stability of aluminum powder, but the improvement effect is limited. At present, the suppliers of aluminum powder pigments on the market have also launched silicon-coated aluminum powder for the water-based coating, such as StapaHydrolan series of ECKART company and AQ series of SILBERLINE company, but due to the high cost of silicon-coated aluminum powder, the average price is about 3 times that of conventional aluminum powder products, and the surface metal texture of aluminum powder will decrease after silicon coating, which affects the final appearance effect, so silicon-coated aluminum powder cannot meet the needs of industry development.

[0006] Therefore, the present application mainly aims at the important color masterbatch component in the water-based repair paint coating system, and aims to provide a water-based color masterbatch composition containing aluminum powder pigments, which has high long-term stability, ensures that the viscosity does not become significantly thick during the use period, does not cause quality and safety problems due to obvious gas swelling, and at the same time maintains excellent metal texture and brightness, meeting the quality requirements of automobile repair. SUMMARY

[0007] Based on the above facts, the purpose of the present application is to provide a water-based color masterbatch composition containing aluminum powder pigments, which improves the technical problem of poor storage of current water-based aluminum powder pigment color masterbatch by using an aluminum powder compound containing phosphate as a passivator for aluminum powder pigments, effectively avoids the gas evolution phenomenon of water-based aluminum powder paint color masterbatch during long-term storage, and after long-term storage, the aluminum powder does not appear discoloration, brightness decrease and other problems caused by blackening of the aluminum powder.

[0008] The first aspect of the present application provides a water-based color masterbatch composition containing aluminum powder pigments, the components of which comprise, by weight:

[0009]

[0010] The total weight of the above components is 100 parts.

[0011] mixed resins

[0012] In the present application, the mixed resin includes a physically cured or self-crosslinking polymer and a water-dispersible resin, and the combination of the two compositions can better realize the drying of the polymer into a film by the volatilization of solvents and water, meeting the needs of physical drying methods in automobile repair paint color paint products.

[0013] The mixed resin comprises, by weight parts:

[0014] Physical curing or self-crosslinking polymer 5-25 parts

[0015] Water-dispersible resin 5-25 parts

[0016] The total weight of the above components is 10-50 parts.

[0017] Further, the physical curing or self-crosslinking polymer is preferably selected from one or a combination of a physical curing polyurethane dispersion or a self-crosslinking polyurethane, and the use of a physical curing polyurethane dispersion or a self-crosslinking polyurethane as the main film-forming resin can provide the coating with excellent mechanical properties and medium resistance of the coating film; the water-dispersible resin can be selected from one or several of a water-dispersible acrylic emulsion, a waterborne polyurethane dispersion, a waterborne polyester resin, a waterborne epoxy resin, and a modified polymer thereof, including but not limited to an acrylic-modified polyurethane dispersion, a polyester-modified polyurethane dispersion, an epoxy-modified acrylic emulsion, and a polyester-modified acrylic, etc.

[0018] Specifically, the physical curing or self-crosslinking polymer is selected from one or a combination of polyurethane resins of types U4000, U9800 (both purchased from Everlight Chemical Material Corp.), and the water-dispersible resin includes but is not limited to an acrylic emulsion of type Setaqua 6803 (purchased from Zannan New Materials Co., Ltd.), etc. U4000, U9800 (both purchased from Everlight Chemical Material Corp.), and the water-dispersible resin includes but is not limited to an acrylic emulsion of type Setaqua 6803 (purchased from Zannan New Materials Co., Ltd.), etc.

[0019] aluminum powder pigments

[0020] In some embodiments of the present application, the aluminum powder pigment can be selected from a pure aluminum pigment without surface treatment or an aluminum powder pigment that has been pretreated for use in waterborne coatings, and the particle size of the aluminum powder is determined according to the needs of color development, preferably 5-50 μm.

[0021] It should be noted that after the aluminum powder pigment is processed into a flaky powder by ball milling, a lubricant such as stearic acid and oleic acid is used for surface protection, so the aluminum powder pigment cannot be directly dispersed in a waterborne system.

[0022] Specifically, the aluminum powder pigment includes but is not limited to an aluminum silver paste of type SPARKLE SILVER PREMIER 353 (purchased from Star Platinum Co., Ltd.), etc.

[0023] aluminum powder pigment encapsulating protectants

[0024] In some embodiments of the present application, the aluminum powder pigment coating protective agent is a block copolymer of epoxy or acrylic and phosphate ester. Such phosphate-based compounds can effectively inhibit corrosion of aluminum powder pigments in aqueous coating compositions, and can improve the anti-gassing property of the aqueous color masterbatch composition, thereby meeting the short-term anti-corrosion requirements of aluminum powder pigments.

[0025] In some preferred embodiments of the present application, the amount of aluminum powder pigment coating protective agent added is related to the amount and surface area of the aluminum powder pigment. Preferably, the amount of aluminum powder pigment coating protective agent is 20% to 60% of the amount of aluminum powder pigment, and more preferably, the amount of aluminum powder pigment coating protective agent is 30% to 50% of the amount of aluminum powder pigment.

[0026] Specifically, the aluminum powder pigment coating protective agent includes, but is not limited to, Lubrizol 2062 (purchased from Lubrizol Corporation) and the like.

[0027] antirust pigments

[0028] In some embodiments of the present application, the anti-rust pigment is selected from one or more of aluminum polyphosphate, zinc, calcium, strontium, and modified versions thereof, as well as aluminum orthophosphate, zinc, calcium, strontium, and modified versions thereof. The anti-rust pigment can form complex ions on the surface of the aluminum powder substrate, covering the corrosion active sites, thereby effectively inhibiting and slowing down the corrosion of the aluminum powder material, and playing a protective role in preventing the aluminum powder pigment from rusting.

[0029] It should be noted that the anti-rust pigment is generally obtained in the form of a powder, and before being added to the formulation, it needs to be dispersed to a finer particle size by the above-mentioned solvents and dispersants, in order to achieve better protective effect and topcoat appearance effect.

[0030] Specifically, the anti-rust pigment is selected from one or more of Halox 430, Halox SZP-391 (both purchased from Halox Corporation, USA), K-white #82, K-white #84S, K-white #105 (all purchased from Imperial Chemical Corporation, Japan), ZP-10, CAPP (all purchased from KCC Corporation), and the like. ZP-10, CAPP (all purchased from KCC Corporation).

[0031] auxiliaries

[0032] In the present application, the auxiliary agents include dispersants, defoamers, wetting agents, thickeners, pH regulators. Among them, the dispersant is added to make the aluminum powder and antirust pigment better dispersed in the water-based system; the defoamer can improve the bubble problem in the production process of water-based paint, and avoid surface defects such as dark bubbles and pinholes in the film forming process, the wetting agent can promote the wetting of the coating on the substrate, prevent the shrinkage problem caused by substrate pollution. The thickener can improve the storage stability and application effect of the water-based color masterbatch composition; the pH regulator is used to adjust the pH value of the coating system.

[0033] The auxiliary agent comprises, by weight:

[0034]

[0035]

[0036] The total weight of the above components is 1-12 parts.

[0037] Specifically, the dispersant includes but is not limited to one or more of the dispersants with model numbers BYK190, BYK191, BYK182 (all purchased from Germany BYK company), Tego752W, Tego755W, Tego757W (all purchased from Degussa company); preferably, the amount of the dispersant is 1%-40% of the content of aluminum powder pigment; more preferably, the amount of the dispersant is 15%-20% of the content of aluminum powder pigment.

[0038] The thickener is selected from one or more of polyurethane associated acrylic emulsion, alkali-swellable acrylic emulsion, hydrophobically modified alkali-swellable acrylic emulsion, polyamide wax, modified ethylene-vinyl acetate copolymer wax emulsion, fumed silica, and layered silicate; more specifically, the thickener is selected from one or more of the thickening agents with model numbers RHEOLATE299 (purchased from Dow Corning Company), Rheotech3900 (purchased from France Akema Company), ACRYSOLASE-60 (purchased from the United States Dow Chemical Company), RHEOVISAS1130 (purchased from BASF Company), DISPARLON AQ-600 (purchased from Japan Disperlon Company), AQUATIX8421 (purchased from Germany BYK Company), and AEROSIL200 (purchased from Germany Wacker Company).

[0039] The defoamer, wetting agent, and pH regulator are conventional water-based auxiliary agents selected by professionals in the field. For example, the defoamer includes but is not limited to the defoamer with model number BYK028 (purchased from Germany BYK Company), the wetting agent includes but is not limited to the wetting agent with model number Wet245 (purchased from Degussa Company), and the pH regulator includes but is not limited to 10% dimethyl ethanolamine aqueous solution, etc.

[0040] solvents

[0041] In the present application, the role of the solvent is to make the aluminum powder pigment better dispersed in the aqueous system. As known from the above, after the aluminum powder pigment is processed into a flaky powder by ball milling, it needs to be surface-protected by using lubricants such as stearic acid and oleic acid, and cannot be directly dispersed in the aqueous system, and needs to be pre-dispersed by using a solvent. Since the amount of the solvent will affect the VOC content of the product, the amount of the solvent should be reduced as much as possible under the premise of meeting the performance requirements of the product.

[0042] In some embodiments of the present application, the solvent is selected from one or more of alcohol, ether, ketone solvents, preferably the solvent is selected from one or more of ethanol, n-propanol, isopropanol, butanol, n-pentanol, n-hexanol, isooctanol, propylene glycol methyl ether, propylene glycol butyl ether, diacetone alcohol, ethylene glycol butyl ether, ethylene glycol isooctyl ether, diethylene glycol methyl ether, dipropylene glycol methyl ether.

[0043] The second aspect of the present application provides a method for preparing the aqueous color master composition containing aluminum powder pigment of the first aspect of the present application, comprising the following steps:

[0044] (1) Put the mixed resin into a stainless steel container A, and add part of deionized water, part of pH adjuster, part of defoaming agent and wetting agent under stirring at 400-600 r / min, stir for 20-30 min, then use part of thickening agent to adjust the viscosity of the obtained mixture, so that the B6 viscosity value is in the range of 1000-1200 mpas when measured by Brookfield viscometer, to obtain resin mixture A.

[0045] (2) Take another stainless steel container B, and add solvent, part of dispersant and aluminum powder pigment under stirring at 300-500 r / min, stir for 30-45 min, then add aluminum powder coating protective agent under stirring at 400-600 r / min, stir for 30-60 min to obtain aluminum powder pigment dispersion B.

[0046] (3) Put part of deionized water into another stainless steel container C, and add the remaining dispersant and the remaining defoaming agent under stirring at 400-600 r / min, stir for 15-30 min, then add the rust-proof pigment, and grind the obtained mixture at a speed of 2000-3000 r / min until the pigment fineness is dispersed to below 5 μm to obtain the rust-proof pigment dispersion C.

[0047] (4) slowly add the aluminum powder pigment dispersion liquid B into the resin mixture A in the stainless steel container A under the condition of stirring at 400-600 r / min, after complete addition, use part of the pH adjusting agent to adjust the pH value of the obtained mixture to 8.5-8.8, then stir at the speed of 400-600 r / min for 30 min, add the anti-rust pigment dispersion liquid C, continue to stir at the speed of 400-600 r / min for 30 min, use the remaining deionized water to adjust the solid content of the obtained mixture to 15-30%, use the remaining thickening agent to adjust the viscosity of the obtained mixture, so that the B6 viscosity value is in the range of 1800-2200 mpas when measured by using the Brookfield viscometer, again use the remaining pH adjusting agent to adjust the pH value of the obtained mixture to 8.2-8.8, and the aluminum powder pigment-containing water-based color master composition is obtained.

[0048] Advantages of the present application

[0049] The aluminum powder pigment-containing water-based color master composition provided by the present application significantly improves the blackening and blistering problems of the aluminum powder pigment in the water-based paint, maintains excellent metallic luster and brightness of the water-based aluminum powder paint, and obtains a long-term stable water-based aluminum powder color master, so as to ensure that the viscosity does not become significantly thick during the use period, and quality and safety problems caused by obvious blistering are avoided, and the common needs of the automobile repair paint industry for water-based environmental protection and excellent appearance are met. DETAILED DESCRIPTION

[0050] In order to more clearly illustrate the present application, the present application will be further described below in combination with specific examples. It should be understood by those skilled in the art that the specific description below is illustrative rather than limiting, and should not limit the protection scope of the present application.

[0051] The technical solutions of the present application will be described below in combination with some more specific examples.

[0052] Example 1: aluminum powder pigment-containing water-based color master composition 1

[0053] The aluminum powder pigment-containing water-based color master composition 1 is prepared according to the formulation shown in Table 1 below:

[0054] Table 1: weight parts of raw materials in Example 1

[0055]

[0056] The preparation of the aluminum powder pigment-containing water-based color master composition 1 includes the following steps:

[0057] (1) Put 21.80 parts of self-made acrylic emulsion into stainless steel container A, and then add 15.20 parts of deionized water, 18.50 parts of polyurethane resin U4000, 0.20 parts of 10% dimethyl ethanolamine aqueous solution, 0.02 parts of defoaming agent BYK028, 0.01 parts of wetting agent Wet245, after stirring for 20-30 min, use 0.80 parts of thickening agent RHEOLATE299 to adjust the viscosity of the obtained mixture, so that the B6 viscosity value is in the range of 1000-1200mpas when measured by Brookfield viscometer, to obtain resin mixture A.

[0058] (2) Take another stainless steel container B, and then add 4.20 parts of butanol, 3.80 parts of ethylene glycol butyl ether, 2.00 parts of dispersant BYK190, 8.60 parts of aluminum paste SPARKLE SILVER PREMIER353 under stirring at 300-500 r / min, after stirring for 30-45 min, add 2.50 parts of aluminum powder coating protective agent Lubrizol2062 under stirring at 400-600 r / min, and after stirring for 30-60 min, obtain aluminum powder dispersion liquid B.

[0059] (3) Put 4.00 parts of deionized water into another stainless steel container C, and then add 0.20 parts of dispersant Tego755W and 0.02 parts of defoaming agent BYK028 under stirring at 400-600 r / min, after stirring for 15-30 min, add 1.00 parts of anti-rust pigment Halox430, and grind the obtained mixture at a speed of 2000-3000 r / min until the pigment fineness is dispersed to below 5 μm, to obtain anti-rust pigment dispersion liquid C.

[0060] (4) Slowly add aluminum powder dispersion liquid B to resin composition A in stainless steel container A under stirring at 400-600 r / min, after complete addition, use 0.20 parts of 10% dimethyl ethanolamine aqueous solution to adjust the pH value of the obtained mixture to 8.5-8.8, and then stir at a speed of 400-600 r / min for 30 min, add anti-rust pigment dispersion liquid C, continue to stir at a speed of 400-600 r / min for 30 min, use 16.41 parts of deionized water to adjust the solid content of the obtained mixture to 23-25%, use 0.34 parts of thickening agent RHEOLATE299 to adjust the viscosity of the obtained mixture, so that the B6 viscosity value is in the range of 1800-2200mpas when measured by Brookfield viscometer, and use 0.20 parts of 10% dimethyl ethanolamine aqueous solution to adjust the pH value of the obtained mixture to 8.2-8.8, to obtain the water-based color master composition 1 containing aluminum powder pigment.

[0061] Example 2: Water-based color masterbatch composition 2 containing aluminum powder pigment

[0062] A water-based color masterbatch composition 2 containing aluminum powder pigment was prepared according to the formulation shown in Table 2 below:

[0063] Table 2 Raw material weight parts of Example 2

[0064]

[0065]

[0066] The preparation of the water-based color masterbatch composition 2 containing aluminum powder pigment included the following steps:

[0067] (1) Put 25.80 parts of acrylic emulsion Setaqua 6803 into a stainless steel container A, and add 11.20 parts of deionized water, 18.50 parts of polyurethane resin U9800, 0.20 parts of 10% dimethyl ethanolamine aqueous solution, 0.02 parts of defoaming agent BYK028, 0.01 parts of wetting agent Wet 245, stir for 20-30 min, then use 0.60 parts of thickening agent ACRYSOLASE-60 to adjust the viscosity of the obtained mixture, so that the B6 viscosity value is in the range of 1000-1200 mpa when measured using a Brookfield viscometer, to obtain resin mixture A.

[0068] (2) Take another stainless steel container B, and add 4.20 parts of butanol, 3.80 parts of ethylene glycol butyl ether, 2.00 parts of dispersant BYK190, 8.60 parts of aluminum silver paste SPARKLE SILVER PREMIER 353 under stirring at 300-500 r / min, stir for 30-45 min, then add 2.50 parts of aluminum powder coating protective agent Lubrizol 2062 under stirring at 400-600 r / min, stir for 30-60 min to obtain aluminum powder dispersion liquid B.

[0069] (3) Put 4.00 parts of deionized water into another stainless steel container C, and add 0.20 parts of dispersant BYK190, 0.02 parts of defoaming agent BYK028 under stirring at 400-600 r / min, stir for 15-30 min, then add 0.80 parts of anti-rust pigment ZP-10, grind the obtained mixture at a speed of 2000-3000 r / min until the pigment fineness is dispersed to below 5 μm to obtain anti-rust pigment dispersion liquid C.

[0070] (4) slowly add the aluminum powder dispersion liquid B to the resin composition A in the stainless steel container A under stirring at 400-600 r / min, after complete addition, adjust the pH value of the obtained mixture to 8.5-8.8 using 0.20 parts of 10% dimethyl ethanolamine aqueous solution, then stir at a speed of 400-600 r / min for 30 min, add the rust-proof pigment dispersion liquid C, continue to stir at a speed of 400-600 r / min for 30 min, adjust the solid content of the obtained mixture to 23-25% using 15.75 parts of deionized water, adjust the viscosity of the obtained mixture using 1.00 parts of thickening agent ACRYSOLASE-60 so that the B6 viscosity value is in the range of 1800-2200 mPa.s when measured using a Brookfield viscometer, adjust the pH value of the obtained mixture to 8.2-8.8 again using 0.60 parts of 10% dimethyl ethanolamine aqueous solution, and the water-based color master composition 2 containing aluminum powder pigment is obtained.

[0071] Examples 3-5: Water-based color master compositions 3-5 containing aluminum powder pigment

[0072] The water-based color master compositions 3-5 containing aluminum powder pigment are prepared according to the formulations shown in Table 3 below:

[0073] Table 3: Weight parts of raw materials for Examples 3-5

[0074]

[0075] The preparation steps of the water-based color master compositions 3-5 containing aluminum powder pigment are the same as those of Example 1.

[0076] Comparative Example 1: Water-based color master 1 as comparative example

[0077] The water-based color master 1 as comparative example is prepared according to the formulation shown in Table 4 below, which is different from Example 1 in that no rust-proof pigment is added.

[0078] Table 4: Weight parts of raw materials for Comparative Example 1

[0079]

[0080] The preparation of the water-based color master 1 as comparative example includes the following steps:

[0081] (1) Put 21.80 parts of self-made acrylic emulsion into a stainless steel container A, and add 15.20 parts of deionized water, 18.50 parts of polyurethane resin U4000, 0.20 parts of 10% dimethyl ethanolamine aqueous solution, 0.02 parts of defoaming agent BYK028, 0.01 parts of wetting agent Wet245, after stirring for 20-30 min, 0.80 parts of thickening agent RHEOLATE 299 was used to adjust the viscosity of the obtained mixture, so that the B6 viscosity value was in the range of 1000-1200 mPas when measured using a Brookfield viscometer, to obtain resin mixture A.

[0082] (2) Another stainless steel container B was taken, 4.20 parts of butanol, 3.80 parts of ethylene glycol butyl ether, 2.00 parts of dispersant BYK190, 8.60 parts of aluminum silver paste SPARKLE SILVER PREMIER 353 were sequentially added under stirring at 300-500 r / min, after stirring for 30-45 min, 2.50 parts of aluminum powder coating protective agent Lubrizol 2062 was added under stirring at 400-600 r / min, after stirring for 30-60 min, to obtain aluminum powder dispersion liquid B.

[0083] (3) The aluminum powder dispersion liquid B was slowly added to the resin composition A in the stainless steel container A under stirring at 400-600 r / min, after complete addition, 0.20 parts of 10% dimethyl ethanolamine aqueous solution was used to adjust the pH value of the obtained mixture to 8.5-8.8, then stirring was carried out at a speed of 400-600 r / min for 30 min, 21.60 parts of deionized water was used to adjust the solid content of the obtained mixture to 22-24%, 0.37 parts of thickening agent RHEOLATE 299 was used to adjust the viscosity of the obtained mixture, so that the B6 viscosity value was in the range of 1800-2200 mPas when measured using a Brookfield viscometer, 0.20 parts of 10% dimethyl ethanolamine aqueous solution was used to adjust the pH value of the obtained mixture to 8.2-8.8, to obtain the water-based aluminum powder color masterbatch 1 as the comparative example.

[0084] It should be noted that in the present comparative example, the formula of the water-based color masterbatch 1 does not contain the anti-rust pigment dispersion liquid with anti-rust pigment as the main component, the amount of anti-rust pigment is 0, which is less than the lower limit of the amount of 0.01 parts claimed in the present application, and is not within the scope of the present application, so this example is only comparative example 1. The lack of anti-rust pigment will lead to the decrease of the stability of the aluminum powder pigment in the system, aggravate the reaction with water in the system, cause the aluminum powder pigment to gradually turn black and lose the metallic luster, the color difference of the color masterbatch before and after storage is large, and the gas evolution amount is high.

[0085] The detection method for the products obtained in the examples and comparative examples

[0086] Item 1: color stability

[0087] Each of the water-based color masterbatches prepared in Examples 1-5 and Comparative Example 1 was placed in a 50°C constant temperature oven, and the color change of the color masterbatches before and after storage was compared after 2 months of storage. The color comparison was performed as follows:

[0088] The water-based color masterbatches after storage and the water-based color masterbatches stored at room temperature for 2 months were each mixed with water-based refinish black color masterbatches at a ratio of 1:1, and then each mixture was uniformly applied to a card using a 150 um wet film applicator, and then the color difference was measured after low-temperature drying. The color change (measured at an angle of 45°) was observed, and the color difference ΔE was calculated using the CIELAB color difference formula (according to GB 11186.3-89).

[0089] Item 2: Gas evolution

[0090] Each of 250 ml of the water-based color masterbatches prepared in Examples 1-5 and Comparative Example 1 was placed in a gas evolution device, and the gas evolution device was placed in a 50°C water bath for 30 minutes. After the temperature was stabilized, the gas evolution device was sealed and then placed in a 50°C water bath for 10 days. The amount of gas evolution was measured by the drainage method (i.e., the amount of water displaced was used to represent the amount of hydrogen gas generated by the reaction of the aluminum powder with water in the water-based color masterbatch).

[0091] The results of the tests on the products obtained in Examples 1-5 and Comparative Example 1 with respect to Items 1-2 are shown in Table 5 below.

[0092] Table 5 Results of the tests on the products obtained in Examples 1-5 and Comparative Example 1 with respect to Items 1-2

[0093]

[0094] As can be seen from the test results in Table 5, in terms of color stability, the color difference between the water-based color masterbatches prepared in Examples 1-5 and the products before storage was small after 2 months of storage in a 50°C constant temperature oven. In terms of gas evolution, the amount of gas evolution of the water-based color masterbatches prepared in Examples 1-5 was small after 10 days of storage in a 50°C constant temperature water bath. It can be seen that the water-based aluminum powder coatings prepared in Examples 1-5 have excellent metallic luster and brightness, and the water-based aluminum powder color masterbatches are stable for a long period of time, and the viscosity does not become significantly thick, and there are no quality and safety problems caused by significant gas evolution during the use period.

[0095] However, the color difference between the water-based color masterbatch prepared in Comparative Example 1 and the product before storage was large (ΔE was 2.65) after 2 months of storage in a 50°C constant temperature oven. In terms of gas evolution, the amount of gas evolution of the water-based color masterbatch prepared in Comparative Example 1 was large (the amount of gas evolution was 119 ml / kg) after 10 days of storage in a 50°C constant temperature water bath. This result shows that the lack of anti-rust pigment can cause the stability of the aluminum powder pigment in the system to decrease, and the reaction of the aluminum powder pigment with the water in the system can be intensified, which can cause the aluminum powder pigment to gradually become black and lose the metallic luster, and the color difference between the color masterbatches before and after storage can be large, and the amount of gas evolution can be high.

[0096] Obviously, the above-mentioned embodiments of the present application are only examples for clearly illustrating the present application, and are not intended to limit the embodiments of the present application. Based on the above-mentioned description, other different forms of changes or variations can be made by those skilled in the art, and here it is impossible to enumerate all the embodiments. Any obvious changes or variations derived from the technical solutions of the present application are still within the protection scope of the present application.

Claims

1. An aqueous color masterbatch composition containing aluminum powder pigment, comprising the following components by weight parts: The total weight of the above components is 100 parts, characterized in that: The aluminum powder pigment coating protective agent is a block copolymer of epoxy or acrylic and phosphate ester; The anti-rust pigment is selected from one or more of polyphosphates of aluminum, zinc, calcium, strontium and their modifiers, and aluminum orthophosphate, zinc, calcium, strontium and their modifiers.

2. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 1, characterized by, The mixed resin comprises, by weight parts: Physical curing or self-crosslinking polymer 5-25 parts Water-dispersible resin 5-25 parts The total weight of the above components is 10-50 parts.

3. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 2, characterized in that: The physical curing or self-crosslinking polymer is selected from one or a combination of physical curing polyurethane dispersion or self-crosslinking polyurethane; The water-dispersible resin is selected from one or more of water-dispersible acrylic emulsion, aqueous polyurethane dispersion, aqueous polyester resin, aqueous epoxy resin and their modified polymers.

4. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 3, characterized in that, The modified polymer is selected from one or more of acrylic modified polyurethane dispersion, polyester modified polyurethane dispersion, epoxy modified acrylic emulsion or polyester modified acrylic.

5. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 1, characterized in that, The particle size of the aluminum powder pigment is 5-50 μm.

6. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 1, characterized in that, The amount of the aluminum powder pigment coating protective agent is 20%-60% of the content of the aluminum powder pigment by weight percentage.

7. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 6, characterized in that, The amount of the aluminum powder pigment coating protective agent is 30%-50% of the content of the aluminum powder pigment by weight percentage.

8. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 1, characterized in that, The auxiliary agent comprises, by weight parts: The total weight of the above components is 1-12 parts.

9. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 8, characterized in that, The amount of the dispersant is 1%-40% of the content of the aluminum powder pigment by weight percentage.

10. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 9, characterized in that, The amount of the dispersant is 15%-20% of the content of the aluminum powder pigment by weight percentage.

11. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 8, characterized in that, The thickening agent is selected from one or more of polyurethane associative acrylic emulsion, alkali-swellable acrylic emulsion, polyamide wax, fumed silica and layered silicate.

12. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 8, characterized in that, The thickening agent is a hydrophobically modified alkali-swellable acrylic emulsion.

13. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 1, characterized in that, The solvent is selected from one or more of alcohol, ether and ketone solvents.

14. The aqueous color masterbatch composition containing aluminum powder pigment according to claim 13, characterized in that, The solvent is selected from one or more of ethanol, n-propanol, isopropanol, butanol, n-pentanol, n-hexanol, isooctanol, propylene glycol methyl ether, propylene glycol butyl ether, diacetone alcohol, ethylene glycol butyl ether, ethylene glycol isooctyl ether, diethylene glycol methyl ether and dipropylene glycol methyl ether.

15. A method for preparing the aqueous color masterbatch composition containing aluminum powder pigment according to claim 8, comprising the following steps: (1) Put the mixed resin into a stainless steel container A, and add part of deionized water, part of pH adjuster, part of defoaming agent and wetting agent under stirring at 400-600 r / min, stir for 20-30 min, then use part of the thickening agent to adjust the viscosity of the obtained mixture to 1000-1200 mpas in B6 viscosity value measured by Brookfield viscometer, to obtain resin mixture A; (2) Take another stainless steel container B, under the condition of stirring at 300-500 r / min, add solvent, part of dispersant and aluminum powder pigment in turn, after stirring for 30-45 min, add the protective agent for aluminum powder pigment under the condition of stirring at 400-600 r / min, after stirring for 30-60 min, obtain the aluminum powder pigment dispersion B; (3) Put part of deionized water into another stainless steel container C, under the condition of stirring at 400-600 r / min, add the rest of dispersant, the rest of defoaming agent, after stirring for 15-30 min, add the antirust pigment, grind the obtained mixture at the speed of 2000-3000 r / min until the fineness of the pigment is dispersed to below 5 μm, obtain the antirust pigment dispersion C; (4) Slowly add the aluminum powder pigment dispersion B into the resin mixture A in the stainless steel container A under the condition of stirring at 400-600 r / min, after complete addition, use part of pH regulator to adjust the pH value of the obtained mixture to 8.5-8.8, then stir at the speed of 400-600 r / min for 30 min, add the antirust pigment dispersion C, continue to stir at the speed of 400-600 r / min for 30 min, use the rest of deionized water to adjust the solid content of the obtained mixture to 15-30%, use the rest of thickening agent to adjust the viscosity of the obtained mixture, so that the B6 viscosity value is in the range of 1800-2200 mpas when measured by using Brookfield viscometer, use the rest of pH regulator to adjust the pH value of the obtained mixture to 8.2-8.8, thus obtain the water-based color master composition containing aluminum powder pigment.

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