Zinc Pigments for Water-Based Anti-Corrosion Coatings

Abstract

A treated zinc pigment that provides cathodic corrosion protection in waterborne zinc-rich coatings is described. The treated zinc pigment exhibits reduced gassing in waterborne formulations.

Description

Background Art

[0001] Structural damage due to metal corrosion is one of the most costly failure modes in metal structures. Strategies used to prevent corrosion of ferrous metals include the use of zinc-rich paints. Zinc-rich paints are typically solvent-based paints containing a high level of metallic zinc particles that provide both cathodic and anodic protection to the steel surface. When the micronized zinc particles are dispersed in water, they corrode, resulting in mass degradation and hydrogen gas evolution. While many paint manufacturers would like zinc pigments that can be formulated into waterborne systems, the technology is currently limited to either 2-part (2K) systems that require more manual work by the user and have a short shelf life (~24 hours), or surface treatments of the zinc particles. These treatments passivate the zinc particles, stabilizing them against corrosion and thereby reducing their anodic protection capabilities.

[0002] Electrochemical processes occurring on the metal surface accelerate the rate of corrosion. The zinc-rich paint forms a zinc-steel electrochemical cell with the zinc and steel becoming the anode and cathode respectively. This protection mechanism has two phases. First, in the cathodic phase, the zinc corrodes sacrificially, forming an impermeable and non-conductive ZnO barrier. As the barrier is formed, the corrosion protection mechanism switches from cathodic to anodic. If the ZnO barrier is damaged, the cathodic phase restarts and the defects close, thus repairing the barrier.

[0003] Most zinc-rich coatings are made using solvent-based systems. In recent years, regulations around the world have forced coatings manufacturers to consider and use water-based alternatives to solvent-based coatings. However, zinc pigments are reactive in water and corrode in storage, causing them to lose their ability to provide cathodic protection to steel. In addition, corrosion of zinc produces hydrogen gas, which can cause container failure, blistering, or in extreme cases, explosions. To formulate zinc pigments into waterborne systems, the pigment must be passivated or formulated as a component that is added by the end user prior to applying the paint.

[0004] The mode of passivation of metallic particles is well known, but conventional passivation methods cannot be used for zinc pigments because they render the zinc non-conductive and reduce its ability to provide cathodic protection.

[0005] Previous work on treated zinc pigments for use in waterborne zinc-rich coatings has described one or more permanent treatments that hinder the ability of the zinc to provide cathodic protection by forming a physical barrier between the zinc pigment and the metal substrate. If the zinc pigment could be stored stably in a waterborne coating while becoming active once applied to the substrate, this would be particularly beneficial for waterborne applications. Summary of the invention

[0006] Zinc-rich paints contain metallic zinc pigments and are applied to metal substrates to provide corrosion protection. Zinc-rich paints provide barrier (anodic) protection and cathodic protection to the substrate. Cathodic protection is an electrochemical process whereby the zinc pigment acts as a sacrificial component in the paint system to protect the underlying metal substrate. The application of zinc-rich paints is currently limited to solvent-based systems because water-based systems cause the zinc pigments to oxidize, resulting in reduced effectiveness and the generation of hydrogen. Existing water-based zinc pigment paints have a shelf life of only a few days and are not suitable for long-term storage. Passivation of the zinc pigment can reduce oxidation and gassing, but this is done at the expense of the activity of the zinc pigment.

[0007] This development addresses this problem by treating the zinc pigment with a transient treatment that is deactivated after application to the substrate. This development describes a temporary treatment for zinc metal. Once the zinc pigment is applied to a part in the coating, it is activated, allowing it to provide cathodic protection. In addition, the treatment protects the zinc when it is in aqueous conditions, increasing shelf life and reactivity. The treated zinc pigment is protected in aqueous systems while still showing good cathodic protection after application to the substrate.

[0008] The use of treated zinc pigments offers benefits to manufacturers seeking to formulate using waterborne systems. Global regulations are requiring reduced solvent use and requiring OEMs to use waterborne formulations. As a result, there is an unmet market need to expand zinc-rich coatings into waterborne applications. The development described here provides a solution for manufacturing these waterborne zinc-rich coatings. The treated pigments contain a surface treatment and metal particles whereby the surface treatment provides oxidation resistance in a waterborne formulation but allows cathodic protection after the coating is applied to the substrate. DETAILED DESCRIPTION

[0009] Developments related to treated metallic pigments for anti-corrosion coatings are described. This development describes a metallic pigment treated with a transient passivation layer. The treatment protects the metal when it is in water and is deactivated once the metallic pigment is applied to a metal substrate. The treated metallic pigment can be formulated into an aqueous system, thereby reducing gas generation and extending the shelf life of the coating. Inks, paints or coatings containing the treated metallic pigments of this development will activate after curing, thereby providing cathodic and anodic protection to ferrous metal substrates.

[0010] The use of treated metallic pigments in waterborne coating systems allows the shelf life of the formulation to be extended by preventing the metallic pigment from corroding in the system. Minimized H2 gas generation demonstrates a longer shelf life compared to untreated pigments. When formulated into a coating system and applied to a metal substrate, the treated metallic pigment maintains good cathodic corrosion protection of the metal substrate.

[0011] In one embodiment, the treated metallic pigment comprises a metallic pigment and at least one organic treatment agent chemical. In general, the treated metallic pigment comprises 75-99.5% (wt / wt%) of the metallic pigment and 0.25-25% (wt / wt%) of the organic treatment agent chemical. The treated metallic pigment may also comprise 1-10% (wt / wt%) of the organic treatment agent chemical. The metallic pigment comprising the treated metallic pigment may be a particulate material comprising a single metal or alloyed metal and a lubricant. The metallic pigment may comprise one or more of the following elements: Zn, Mg, Cd, Al, Fe, Cr, Cu and mixtures and alloys thereof. Similarly, the color of the metallic pigment may be any color, including silver, gray, copper, black or white. Usually, but not always, the color is determined by the shape of the pigment.

[0012] The treated metallic anticorrosive pigment of the present development can be in any shape, including, for example, spherical, flaky, needle-shaped or amorphous shapes. In addition, the metallic pigment can be a mixture of multiple shapes. The metallic pigment of the present development can also have a particle size and particle size distribution that varies depending on the application. The median (d50) of the particle size distribution is preferably in the range of 1 μm ≤ d50 ≤ 100 μm, more preferably in the range of 5 μm ≤ d50 ≤ 25 μm.

[0013] In one embodiment, the surface of the treated metallic anti-corrosion pigment may be oxidized. If the surface of the treated metallic anti-corrosion pigment is oxidized, the oxide layer may be compound M x R y , wherein M is a metal, and R is a counterion describing an oxide. The coefficients x and y represent the number of metal atoms (M) and counterions (R), respectively. The M of the oxide product can be the same metal comprising the treated metallic pigment, or it can be a different metal. M can also represent a mixture of metals. The metal of the metal atom M can include one or more metals from the following list of Zn, Al, Mg, Cu, Cd, Si, Fe, Cr and Mn. The counterion (R) of the oxide product can be a single counterion or can be composed of a plurality of counterions. The example of suitable counterions R includes, but is not limited to, one or more from the following list including: 2- 、(OH) - 、(OOH)- , S 2- 、(CO3) 2- 、(HCO3) 1- 、(PO4) 3- And mixtures thereof. The treated metallic anticorrosion pigment may contain up to 50% (wt / wt) M x R y .

[0014] Treated metallic pigments can also contain lubricants. Lubricants can be used as processing aids during pigment manufacturing. Typical lubricants used during the metallic pigment processing include all types of saturated and unsaturated fatty acids and mixtures thereof, including but not limited to stearic acid, oleic acid, linoleic acid, ricinoleic acid, palmitic acid, arachidic acid, myristic acid, lauric acid, capric acid, elaidic acid, erucic acid, linolenic acid, myristoleic acid, palmitoleic acid and other fatty acids. The fatty acid used as lubricant can be saturated or undersaturated and contain 1-30 carbon atoms. Used lubricants can account for the 0.1-10 weight % of total pigment.

[0015] In one embodiment, the treated metallic pigment comprises a surface treatment agent containing an organic treatment agent chemical as described below. Without being bound by theory, it is expected that the surface treatment agent prevents the pigment from oxidizing until the pigment is added to the ink or paint and is applied to the surface. After the treated anticorrosive pigment is applied to the surface, the treatment agent is deactivated, thereby allowing the treated metallic pigment to fully participate in cathodic protection. The treatment agent may undergo physical changes in size, shape, morphology or porosity. The treatment agent may undergo phase change, wherein it changes from a solid to a gas or changes from a liquid to a gas. The treatment agent can enable the treated metallic anticorrosive pigment to be formulated into an aqueous system without incompatibility. The selected organic treatment agent chemical should not hinder the ability of the zinc pigment to provide cathodic protection for the substrate.

[0016] The pigment composition comprises a zinc pigment treated with a transient treatment agent, wherein the treatment agent can be added at 0.25-25% (by weight) or 1-10% (by weight). The exact amount of the treatment agent required depends on the morphology, size and surface area of ​​the metallic pigment substrate. The treatment agent can be homogeneous or can be a mixture of different structures that can be defined by Formula 1 and / or Formula 5. The treatment agent has a vapor pressure ranging from 0.0-0.1 mmHg at 20-30°C, and also has a vapor pressure ranging from 0-0.045 mmHg at 20-30°C. The treatment agent is solid and has a measurable vapor pressure at room temperature or near room temperature (20-30°C). It is worth noting that the silica in Comparative Example 12 has no vapor pressure and is therefore not suitable for this product.

[0017] Additionally, the treating agent may maintain volatility and may be sublimable. Without being bound by theory, the treating agent must maintain the ability to volatilize quickly and completely at ambient temperature.

[0018] In one embodiment, the organic treatment agent chemical has a chemical structure according to Formula 1

[0019]

[0020] wherein C1 and C2 are carbon atoms attached via an optional linker L; X1 and X2 represent O, N or S atoms, are independent of each other, and are covalently attached to carbon atoms C1 and C2, respectively; R1, R2, R4 and R5 are optional, independent organic groups or hydrogen atoms; and R3 and R6 are independently organic groups covalently attached to C1 and C2, respectively.

[0021] The carbon atoms C1 and C2 may be covalently attached to each other, or they may be separated by an optional linker group L. In the case where the carbon atoms C1 and C2 are directly bonded to each other, they may be bonded by a single bond or a double bond. In the case where the optional linker group L is located between the carbon atoms C1 and C2, the optional linker group L may contain 0-3 carbon atoms, which are covalently attached to each other and the carbon atoms C1 and C2 by a single bond or a double bond.

[0022] Heteroatoms X1 and X2 can be bonded to carbon atoms C1 and C2 single or double bonds. Heteroatoms X1 and X2 can be O, N and S. In one embodiment, X1 and X2 are atoms of the same type. In another embodiment, X1 and X2 are different atoms. In one embodiment, heteroatoms X1 and X2 are connected to optional groups R1 and R4 respectively. In one embodiment, only one of the groups R1 and R4 can exist and be attached to X1 and X2. In another embodiment, R1 and R4 can both exist. R1 and R4 can be the same or they can be different functional groups without limiting the scope. In one embodiment, optional groups R1 and R4 can be hydrogen atoms or organic groups. In the case where R1 and R4 are organic groups, R1 and R4 can be connected to functional groups R3 and R6 respectively to form a ring system. In this case, the ring system can be aromatic, but it may not be aromatic. In the case of forming a ring system, the ring can contain R1X1C1R3 and R4X2C2R6 respectively.

[0023] In one embodiment, carbon atom C1 and C2 are bonded to optional radicals R2 and R5 respectively. In one embodiment, only one of radicals R2 and R5 can exist and be attached to C1 and C2. In another embodiment, R2 and R5 can both exist. R2 and R5 can be identical or they can be different functional groups without limiting the scope. In one embodiment, optional radicals R2 and R5 can be hydrogen atoms or organic groups.

[0024] Carbon atoms C1 and C2 are bonded to groups R3 and R6, respectively. R3 and R6 can be identical or they can be different functional groups without limiting the scope. R3 and R6 can be connected to heteroatoms X1 and X2 through functional groups R1 and R4, respectively, to form a ring system. In this case, the ring system can be aromatic, but it may not be aromatic. In the case of forming a ring system, the ring may include R1X1C1R3 and R4X2C2R6. The ring structure may be symmetrical, wherein R1X1C1R3 and R4X2C2R6 have the same structure, or it may be asymmetrical, wherein R1X1C1R3 and R4X2C2R6 have different structures. Alternatively, there may be only one ring structure, such as only R1X1C1R3 or only R4X2C2R6, without limiting the scope.

[0025] Examples of suitable ring systems include, but are not limited to, pyrrolidine, pyrroline, pyrrole, imidazolidine, pyrazoline, pyrazole, imidazole, triazole, furan, dioxolane, thiophene, oxazole, isoxazole, isothiazole, thiazole, oxathiolane, thiadiazole, oxadiazole, piperidine, pyridine, piperazine, pyridazine, pyrimidine, pyrazine, triazine, pyran, dioxane, thiazine, thiopyran, dithiane, purine, adenine, guanine, uracil, thymine, cytosine, xanthine, trithiane, morpholine, oxazine, thiomorpholine, thiazine, aza Diazepines Oxepane, thiepine, azocane and thiocane. The ring structure described can be substituted by a linear or cyclic moiety. The substituents may include, but are not limited to, alkanes, olefins, alkynes, amines, alcohols, ethers, alkyl halides, ketones, aldehydes, nitrites, amides, esters and carboxylic acids. In addition, R3 may be connected to R6 to form a ring system. In this case, the ring system may be aromatic, but may not be aromatic. In the case of forming a ring system, the ring may contain C1C2LR4R6.

[0026] In one embodiment, Formula 1 may be a molecule such as curcumin (Formula 2), 2,2'-bipyridine (Formula 3), or 8-hydroxyquinoline (Formula 4).

[0027]

[0028] Other suitable treating agents according to Formula 1 may include salicylic acid, guaiacol, thioguaiacol, maltol, thiomaltol hydroxypyridone, benzil, acetylacetonate, hexafluoroacetylacetone, trifluoroacetylacetone, 1,2-cyclohexanedione, 1,2-cyclopentanedione, pyruvic acid, dimedone, substituted 1,3-diketones, acetonylacetone, glyoxal-bis(mesityl imine) and 2,2'-biphenol.

[0029] In another embodiment, the organic treatment agent chemical has a chemical structure according to Formula 5

[0030]

[0031] Wherein X1, X2 and X3 are heteroatoms in the five-membered ring structure, which are C, O, N or S atoms, are independent of each other, and can be connected by single bonds or double bonds; R1 and R2 represent independent organic groups that can be connected to the ring system, or hydrogen atoms; R3, R4 and R5 are optional, independent organic groups or hydrogen atoms.

[0032] Heteroatoms X1, X2 and X3 can be one or more selected from the group comprising C, O, N or S. Heteroatoms X1, X2 and X3 are part of the 5-membered covalent ring system highlighted in Formula 5. Single bonds or double bonds can exist between any of the core atoms in the five-membered ring of Formula 5. In one embodiment, heteroatoms X1, X2 and X3 can be protonated. In this case, one or all of R3, R4 and R5 will be a hydrogen atom. In one embodiment, heteroatoms X1, X2 and X3 can be positively charged or negatively charged without limiting the scope of this development.

[0033] The radical R1 and R2 can be independently organic groups or hydrogen atoms. R1 and R2 can be identical or they can be different functional groups without limiting the scope. In one embodiment, the optional radical R1 and R2 can be hydrogen atoms or organic groups. When R1 and R2 are organic groups, the group can form a ring system in which R1 and R2 are connected to each other.

[0034] The group R3, R4 and R5 are optional functional groups that may exist or not exist, or they may be hydrogen atoms or organic groups. In one embodiment, only one of the group R3, R4 and R5 may exist. In another embodiment, two R3, R4 and R5 groups may exist. In another embodiment, all R3, R4, and R5 may exist. R3, R4, and R5 may be identical or they may be different functional groups and not limiting the scope.

[0035] Examples of suitable molecules for the structure described in Formula 5 include, but are not limited to, pyrrolidine, pyrroline, pyrrole, pyrazolidine, imidazolidine, triazole, tetrahydrothiophene, thiophene, oxazole, isoxazole, isothiazole, thiazole, oxathiolane, oxadiazole, thiadiazole, pyrrolazine, indene, indoline, indole, indolizine, indazole, benzimidazole, azaindole, azaindazole, purine, benzothiophene, benzisoxazole, benzisothiazole, benzoxazole, benzotriazole, benzothiazole, benzothiadiazole, adenine, guanine, histidine, proline and tryptophan. The described structure may be substituted by linear or cyclic moieties. Substituents may include, but are not limited to, alkanes, olefins, alkynes, amines, alcohols, ethers, alkyl halides, ketones, aldehydes, nitrile, amides, esters and carboxylic acids. In one embodiment, Formula 5 may be a molecule such as benzotriazole (Formula 6), benzimidazole (Formula 7), 3,5-dimethylpyrazole (Formula 8), or 1H-benzimidazole-6-carboxylic acid (Formula 9).

[0036]

[0037] The organic treatment chemical ("treatment") may consist of a single chemical or a combination of more than one chemical. While not being bound by theory, it is proposed that the organic treatment chemicals according to Formula 1 and Formula 5 interact with the surface of the metallic pigment via chemical adsorption, thereby creating a network structure that can be broken down once the coating containing the pigment has been cured.

[0038] The pigment composition comprises a zinc pigment treated with a transient treatment agent, wherein the treatment agent can be added at 0.25-25% (by weight) or 1-10% (by weight). The exact amount of the treatment agent required depends on the morphology, size and surface area of ​​the metallic pigment substrate. The treatment agent can be homogeneous or can be a mixture of different structures that can be defined by Formula 1 and / or Formula 5. The treatment agent has a vapor pressure ranging from 0.0-0.1 mmHg at 20-30°C, and also has a vapor pressure ranging from 0-0.045 mmHg at 20-30°C. The treatment agent is solid and has a measurable vapor pressure at room temperature or near room temperature (20-30°C). It is worth noting that the silica in Comparative Example 12 has no vapor pressure and is therefore not suitable for this product.

[0039] In addition, the treating agent may maintain volatility and may be sublimable. The treating agent chemical has a vapor pressure greater than 0 mmHG but less than 0.1 mmHG at 20-30°C. Without being bound by theory, the treating agent must maintain the ability to volatilize quickly and completely at ambient temperature.

[0040] The exact method for preparing the treated metallic pigment is not important, and any method known to those skilled in the art can be used. In one case, the treated metallic pigment is produced by combining the metallic pigment substrate with a treatment agent in a solvent, subsequently mixing, and optionally drying. In one case, the treatment agent and metallic pigment can be combined in the absence of a solvent. In one case, the treated metallic pigment is produced in a ball mill by adding a treatment agent to a precursor of the metallic pigment.

[0041] The treated metallic pigments of the present development can be used in any type of water-based or solvent-based liquid coating known to skilled formulators. In another embodiment, the coating binder can be an organic, ceramic or hybrid organic ceramic based coating. In one embodiment, the coating can be a 1-part formulation. In another embodiment, the coating can have more than one part in its formulation. In general, metallic pigments can be used in all types of coatings without limiting the scope of the present development.

[0042] Water-based or solvent-based liquid coatings containing treated metallic pigments are characterized by their pigment volume concentration (PVC). Pigment volume concentration (PVC) is defined as the volume fraction of pigment particles compared to the volume fraction of total solids in the coating. The loading of metallic pigment in the coating is such that the PVC of the coating is at or below the critical pigment volume concentration (CPVC). CPVC is defined as the pigment volume concentration at which there is just enough binder present in the coating to cover each pigment particle with a thin layer and the interstices between the particles are filled. It is defined by the following equation, where p p is the specific gravity of the treated metallic pigment, ρ o is the specific gravity of the oil, and OA is the oil absorption in grams of oil of the pigment used to wet 100 grams of the standard oil used in the system.

[0043]

[0044] Oil absorption is usually determined by measuring the amount of liquid that 1 gram of treated metallic pigment can absorb before it wets to form a hard but spreadable paste with a glossy top. It is usually reported in grams of oil / 100 grams of pigment. For this measurement, the oil can be any type of solvent commonly used in solvent-based or water-based coatings, including linseed oil, castor oil, glycols, etc., without limiting the scope of this development.

[0045] The coating system containing treated metallic pigments can be applied to all types of metal parts including metal panels, screws, fasteners, brakes, automatic chassis components, without limiting the scope of this development. The coating system containing treated metallic pigments can be applied to many different metals and alloys, including but not limited to steel, iron, cast iron, wrought iron, Elinvar, Fernico, ferroalloys, Invar, pig iron, hydrogenated iron, Kanthal, Kovar, Spiegeleisen, aluminum and depleted uranium alloys. This development can be formulated into such a coating system, which provides additional benefits, including but not limited to thermal protection, structural reinforcement, impact resistance, wear resistance, friction control and corrosion protection.

[0046] The present development has been described in detail, including its preferred embodiments. However, it will be appreciated that persons skilled in the art, upon consideration of this disclosure, may modify and / or improve upon the present development within the scope and spirit of the present development.

[0047] Example

[0048] The present development is further described by the following non-limiting examples, which further illustrate the present development and are not intended to, and should not be construed to, limit the scope of the present development.

[0049] Examples 1-11

[0050] Overview: 250 g of pigment and 50 g of isopropyl alcohol were added to a planetary mixer and mixed for 15 minutes. A description of the pigments used in Examples 1-13 is provided in Table 1. A solution of treatment chemical in 10 g of isopropyl alcohol and 2 g of water was prepared. The treatment chemical solution was added to the pigment paste and mixed for 30 minutes. The treated paste was then transferred to a vacuum oven equipped with an inert gas purge and dried at 60°C for 12 hours. The treatment chemicals used, the amounts of treatment chemicals, and the zinc pigment substrate are summarized in Table 2.

[0051] Table 1: Description of metallic pigments used in the examples

[0052] Pigment Name Manufacturer describe BendaLutz Z2031 Sun Chemical Amorphous zinc powder BendaLutz Z1047 Sun Chemical 90% zinc flake paste in mineral spirits Zinkpulver EE / C(319) Sun Chemical Zinc powder

[0053] Table 2: discloses the amount and type of treatment chemical used, vapor pressure of the treatment, metallic pigment substrate, gas test results from Machu corrosion testing and rust rating.

[0054]

[0055]

[0056] Comparative Example 12 (based on silica treating agent):

[0057] 110.86g zinc pigment Z2031 is added to an oil jacket reactor with 310.0g isopropanol and the pigment is allowed to soak for 30 minutes. After soaking, the mixture is stirred at 360rpm and heated to rolling reflux (about 83°C). 19.56g TEOS (tetraethyl orthosilicate) is added to the reactor. 40.28g of 3% ammonium hydroxide solution is slowly added to the reactor within 60 minutes. After addition, the reactant is kept at a constant temperature and stirring speed for 60 minutes. The slurry is discharged from the reactor and filtered, and then washed with isopropanol. The pigment is dried in a vacuum oven equipped with an inert gas purge to dry at 60°C for 12 hours. A dark metal powder is produced.

[0058] Comparative Example 13 (without treatment agent): Sun Chemical zinc pigment Z2031

[0059] Comparative Example 14 (without treatment agent): Sun Chemical zinc pigment Z1047

[0060] Comparative Example 15 (without treatment agent): Sun Chemical ZinkPulver EE / C (319) Zinc powder gas test:

[0061] In a 250mL Erlenmeyer flask, 6.6g of pigment, 10g of 2-butoxyethanol, and 90g of water were added in the presence of a magnetic stirring bar. The flask was placed in an oil bath on a stirring plate, stirred at 400rpm, and the oil bath was heated to 40°C. Once the contents of the flask were heated, a glass gasifier was connected to the flask. The glass gasifier allows gas to flow from the flask into the water-containing chamber. As hydrogen is generated, the water chamber becomes pressurized and water is discharged from the chamber into a graduated reservoir. The amount of water discharged is monitored over time - the more water is discharged, the more gas is generated. Each test was run until failure, which was defined as a discharge of >100mL of water or until 30 days had passed. The results are reported as the number of days the sample lasts until failure. The longer the number of days to failure, the better the performance.

[0062] The results of the gas testing demonstrate that the treated zinc pigment of this development can withstand gassing for a longer period of time than the untreated zinc pigment. The advantage of using this development formulation in an aqueous system is that it allows for an extended shelf life compared to the untreated zinc pigment. The exception is Comparative Example 12, which does withstand gassing but performs very poorly in the Machu corrosion test.

[0063] Water-based (WB) paints and spraying procedures:

[0064] WB paint system is made by first mixing WB paint system base material formula.The paint system base material formula can be found in Table 3.Base material formula is made by creating a stirring vortex of water and BYK-1710, and then the ingredients of component 1 are added to the vortex in the listed order.Stir for 5-10 minutes.Once all components have been added, component 2 is added to the vortex.Component 3 is premixed together, and then finally added to the vortex to complete the formulation of the paint base material system.Final paint is made by combining 85.44g base material, 7.25g deionized water, 1.2g Nueodex Web Combi drier and 55g pigment.These ingredients are mixed 15 minutes with a dispersant high shear mixer (1700rpm) in a spray cup.Then the paint is sprayed onto the uncoated steel panel (ACT 10162) cleaned with acetone via a spray gun.The target film thickness applied at room temperature is 0.3-0.5 mil. The panels were then cured at 100°C for 1 hour and allowed to stand overnight. The back of the sprayed panels was sprayed with Rust-Oleum Professional High Performance Enamel 7578838 Flat Black to prevent contamination from the front to the back of the test panels. Examples 11 and 15 were not sprayed due to the large particle size of their pigments not being able to pass through the spray gun.

[0065] Table 3: Formulation of base materials for water-based paint systems

[0066]

[0067] Machu Test:

[0068] The corrosion resistance of the sprayed panels was tested in the Machu test. 10g NaCl salt solution, 10g glacial acetic acid and 5g 30% hydrogen peroxide were added to a 1L volumetric flask, and the remaining volume was filled with deionized water. The solution was inverted / mixed to dissolve all components. The solution was emptied into a 1L beaker, and the test panel was then immersed in the solution for 48 hours. After 48 hours, the panel was removed and rinsed with deionized water, and the rust grade reported in Table 3 was evaluated via ASTM D610-08. Low rust grades indicate that the panel is more corroded, while high rust grades indicate better corrosion protection. The sprayed control panel does not contain pigment and results in a rust grade of 0 (very poor). Although Comparative Example 12 shows gas resistance, it shows poor corrosion resistance. Comparative Examples 13 and 14 show corrosion protection, but perform poorly in gas tests. Note that none of the comparative examples show a combination of gas resistance and corrosion resistance that is apparent in the embodiments of the present invention.

Claims

1. A treated metallic zinc pigment comprising a surface treatment agent containing an organic treatment agent chemical, wherein the treated metallic zinc pigment comprises 75-99.5% wt / wt% of a zinc pigment and 0.25-25% wt / wt% of an organic treatment agent chemical selected from Formula 1 and Formula 5, wherein the vapor pressure of the organic treatment agent chemical is 0-0.045 mmHg at 20-30° C., wherein Formula 1 is: wherein C1 and C2 are carbon atoms attached via an optional linker L; X1 and X2 are O, N or S atoms, independently of each other, and covalently attached to carbon atoms C1 and C2, respectively; R1, R2, R4 and R5 are optional, independent organic groups or hydrogen atoms; and R3 and R6 are independently organic groups covalently attached to C1 and C2, respectively; and wherein Formula 5 is: Wherein X1, X2 and X3 are heteroatoms in the five-membered ring structure, which are C, O, N or S atoms, are independent of each other, and can be connected by double bonds; R1 and R2 represent independent organic groups connected to the ring system, or hydrogen atoms; R3, R4 and R5 are optional, independent organic groups or hydrogen atoms.

2. The treated metallic zinc pigment of claim 1 comprising 90-99% wt / wt% zinc pigment and 1-10% wt / wt% organic treating agent chemical.

3. The treated metallic zinc pigment of claim 1, wherein the zinc pigment is in a shape selected from the group consisting of spheres, flakes, needles, amorphous shapes, and mixtures thereof.

4. The treated metallic zinc pigment of claim 1, wherein the zinc pigment has a median particle size distribution d50 of 1 μm ≤ d50 ≤ 100 μm.

5. The treated metallic zinc pigment of claim 4, wherein the zinc pigment has a median particle size distribution d50 in the range of 5 μm ≤ d50 ≤ 25 μm.

6. The treated metallic zinc pigment of claim 1 further comprising a lubricant selected from the group consisting of saturated and unsaturated fatty acids and mixtures thereof.

7. The treated metallic zinc pigment of claim 1, wherein the organic treatment agent chemical is Formula 1.

8. The treated metallic zinc pigment of claim 7, wherein Formula 1 is selected from the group consisting of curcumin, 2,2'-bipyridine, 8-hydroxyquinoline, salicylic acid, guaiacol, thioguaiacol, maltol, thiomaltol hydroxypyridone, benzil, acetylacetonate, hexafluoroacetylacetone, trifluoroacetylacetone, 1,2-cyclohexanedione, 1,2-cyclopentanedione, pyruvic acid, dimedone, substituted 1,3-diketones, acetonylacetone, glyoxal-bis(mesityl imine) and 2,2'-biphenol, and combinations thereof.

9. The treated metallic zinc pigment of claim 8, wherein Formula 1 is selected from the group consisting of curcumin, 2,2'-bipyridine, 8-hydroxyquinoline, and combinations thereof.

10. The treated metallic zinc pigment of claim 1, wherein the organic treatment agent chemical is Formula 5.

11. The treated metallic zinc pigment of claim 10, wherein Formula 5 is selected from the group consisting of pyrrolidine, pyrroline, pyrrole, pyrazolidine, imidazolidine, triazole, tetrahydrothiophene, thiophene, oxazole, isoxazole, isothiazole, thiazole, oxathiolane, oxadiazole, thiadiazole, pyrrolazine, indene, dihydroindole, indole, indolizine, indazole, benzimidazole, azaindole, azaindazole, purine, benzothiophene, benzisoxazole, benzisothiazole, benzoxazole, benzotriazole, benzothiazole, benzothiadiazole, adenine, guanine, histidine, proline and tryptophan, and combinations thereof.

12. The treated metallic zinc pigment of claim 11, wherein Formula 5 is selected from the group consisting of benzimidazole, benzotriazole, and benzothiazole.

13. A metal part comprising the treated metallic zinc pigment of claim 1.

14. The metal component of claim 13, wherein the metal component is selected from the group consisting of steel, iron, cast iron, wrought iron, Allinvar, Fenicol, ferroalloys, Invar, pig iron, hydrogenated iron, Bartal, Kovar, Specular iron, aluminum, and depleted uranium alloys.

15. A paint comprising the treated metallic zinc pigment of claim 1.

16. An ink comprising the treated metallic zinc pigment of claim 1.

17. A coating system comprising the treated metallic zinc pigment of claim 1.

18. The coating system of claim 17, wherein the coating system is applied to metals and alloys.

19. The coating system of claim 18, wherein the metals and alloys are selected from the group consisting of steel, iron, cast iron, wrought iron, Allinvar, Fenicol, ferroalloys, Invar, pig iron, hydrogenated iron, Bartal, Kovar, Specular iron, aluminum, and depleted uranium alloys.

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