RU2713522C1 - Activating liquid for washing during substrate treatment - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention relates to activating liquid for washing during metal substrate treatment. Activating liquid contains a dispersion of metal phosphate particles having particle size D₉₀ not more than 10 mcm, in which the metal phosphate contains bivalent or trivalent metals or combinations thereof, dispersant and salt of metal sulphate, which contains metal in form of nickel, cobalt, zinc, iron, copper or their combinations. Particle size D₉₀ relates to weighted average particle size distribution, in which 90 % of particles have diameter smaller than D_90. Also disclosed are a method of treating a metal substrate with an activating liquid for washing and a metal substrate treated with said activating liquid.

EFFECT: invention enables to form a metal-phosphate coating on the surface of a metal substrate, having a low coating weight, a smaller size of phosphate crystals and improved adhesion characteristics.

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Description

FIELD OF THE INVENTION

An activating liquid for washing during processing of a metal substrate is proposed.

State of the art

Phosphate conversion coatings are known to be used to treat metal surfaces, especially metals of iron, zinc and aluminum and their alloys. After application, these phosphate coatings form a phosphate layer, mainly of crystals of zinc phosphate and iron, which provide corrosion resistance and / or enhance the adhesion of subsequently applied coatings.

Prior to applying the phosphate coating, the metal substrate is usually “conditioned” or “activated” by exposing the surface of the metal substrate to a diluted aqueous dispersion, sometimes called an activating rinse liquid or activator, by introducing or immersing the metal substrate into a reservoir that contains an activating rinse liquid. "Activation" of the surface of the metal substrate is often achieved due to the adsorption of colloidal titanophosphate particles that are present in the activating wash liquid onto the metal surface. These colloidal titanophosphate particles, however, tend to agglomerate in the activating wash liquid due to the dissolved cations that are typically present in the conditioning wash liquid solution.

A phosphate conversion coating is typically applied to a substrate by immersing the substrate in a heated bath containing metallophosphate particles.

SUMMARY OF THE INVENTION

An activating rinsing liquid for treating a substrate is provided, wherein the rinsing activating liquid comprises a dispersion of metal phosphate particles having a particle size of D _{90 of} not more than 10 μm, where the metal phosphate includes divalent or trivalent metals, or combinations thereof; dispersant; and a metal sulfate salt.

SUBSTANCE: proposed is an activating washing liquid for processing a substrate, an activating washing liquid contains: a dispersion of essentially fine particles of metal phosphate having a particle size D _{90 of} not more than 1 μm, where the metal phosphate includes divalent or trivalent metals or combinations thereof; and dispersant.

Methods are also provided for treating a substrate of one of the activating washing liquids.

Also provided are substrates treated with one of the activating wash liquids.

Detailed description

In accordance with the present invention, an activating rinsing liquid for treating a substrate is provided. In accordance with the present invention, the activating liquid for washing contains or in some cases consists of, or in some cases consists essentially of: a dispersion of metal phosphate particles of divalent metals, trivalent metals or combinations thereof, metal phosphate particles have a particle size D _{90 of} not more than than 10 microns; dispersant; and optionally a metal sulfate salt.

Used in the present description, the term "activating liquid for washing" refers to a continuous aqueous medium containing dispersed and / or suspended in it particles of metal phosphate, which are applied to at least part of the substrate and / or in which at least part the substrates are immersed in order to “activate” or “condition” the substrate in order to promote the formation of a metallophosphate coating on at least a portion of the substrate treated with the activating washing liquid. As used herein, the term “activate” or “condition” the surface of a substrate means creating nucleation sites on the surface of the substrate. Not wishing to be bound by any theory, the applicants believe that such nucleation centers contribute to the formation of metal phosphate crystals on the surface of the substrate, when the surface of the substrate is subsequently treated with a composition for pretreatment with metal phosphate. For example, it is believed that activation of the surface of the substrate creates nucleation sites that promote the formation of zinc phosphate and zinc / iron crystals on the surface of the substrate when the surface of the substrate is pretreated with a zinc phosphate pretreatment composition.

Non-limiting examples of suitable substrates that can be treated with an activating rinse include, but are not limited to, a metal and / or metal alloy substrate. For example, the metal and / or metal alloy may contain or be aluminum, steel or zinc. In accordance with the present invention, the steel substrate may include cold rolled steel, galvanized steel and hot dip galvanized steel. In accordance with the present invention, the substrate may include a vehicle part, such as a vehicle body (for example, without limitation, a door, a body panel, a trunk panel, a roof panel, a hood and / or a cover) and / or a frame.

As used herein, the term “vehicle” or variants thereof include, but are not limited to, civilian, commercial, and military land vehicles such as automobiles and trucks.

As used herein, the term “dispersion” refers to a biphasic transparent, translucent, or opaque system in which metal phosphate particles are in a dispersed phase and an aqueous medium that includes water is in a continuous phase. An “aqueous medium” is a liquid medium that comprises 50 weight percent or more of water, with a weight percent based on the non-solid content of the activating wash liquid. The aqueous medium may contain 50 weight percent or less of other organic cosolvents, for example, 10 weight percent or less. In accordance with the present invention, organic cosolvents are at least partially miscible with water. Miscible with water, organic solvents may be present in the aqueous medium, for example, alcohols with up to about 8 carbon atoms such as methanol, isopropanol and the like, or glycol ethers such as ethylene glycol monoalkyl ethers, diethylene glycol or propylene glycol and the like .

As used herein, the term "finely divided" refers to particles having variable aspect ratios, where the term "aspect ratio" refers to the ratio of the length to the width of the particle (i.e., the aspect ratio does not define the sphere).

In accordance with the present invention, metal phosphate particles of a dispersion of metal phosphate particles of divalent or trivalent metals or combinations thereof may have a particle size of D ₉₀ that does not exceed 10 μm, for example not more than 8 μm, such as not more than 5 μm, for example not more than 2 μm, for example not more than 1 μm, and in some cases may be at least 0.06 μm, for example at least 0.1 μm, for example at least 0.2 μm. In accordance with the present invention, metal phosphate particles of a dispersion of phosphate particles of divalent or trivalent metals, or combinations thereof, can have a particle size of D ₉₀ from 0.06 μm to 8 μm, for example from 0.1 μm to 5 μm, for example from 0.2 μm up to 2 microns.

As used herein, the particle size “D ₉₀ ” refers to a volume-weighted average particle size distribution (particle size) in which 90% of the particles in the particle distribution have a diameter smaller than the “D ₉₀ ” value. As used herein, the particle size “D ₁₀ ” refers to a volume-weighted average particle distribution in which 10% of the particles in the particle distribution have a diameter smaller than the “D ₁₀ ” value. As used herein, the term “D ₅₀ ” particle size refers to a volume-weighted average particle distribution in which 50% of the particles in the particle distribution have a diameter smaller than the “D ₅₀ ” value.

In accordance with the present invention, the particle size can be measured using a tool such as Mastersizer 2000, available from Malvern Instruments, Ltd., Malvern, Worcestershire, UK or an equivalent tool. Mastersizer 2000 directs a laser beam (diameter 0.633 mm, wavelength 633 nm) through a dispersion of particles (in distilled, deionized or filtered water up to 2-3% shading) and measures the scattering of light on the dispersion (measurement parameters 25 ° C, 2200 rpm / min, 30 seconds of preliminary delay, 10 seconds of background measurement, 10 seconds of sample measurement). The amount of light scattered by the dispersion is inversely proportional to the particle size. A series of detectors measures the scattered light, and then the data is analyzed using software (Malvern Mastersizer 2000 software, version 5.60) to generate a particle size distribution from which the particle size can be determined in the usual way.

In accordance with the present invention, a particle dispersion sample may optionally be sonicated before particle size analysis. In accordance with the present invention, an ultrasonic treatment process includes: (1) mixing a particle dispersion using a vortex mixer (Fisher Scientific Vortex Genie 2 or equivalent); (2) adding 15 ml of distilled deionized, ultrafiltered water to a 20 ml screw cap scintillation vial; (3) adding 4 drops of dispersion to the vial; (4) mixing the contents of the vial using a vortex mixer; (5) closing the vial and placing it in an ultrasonic water bath (Fisher Scientific Model FS30 or equivalent) for 5 minutes; (6) shaking the vial again; and (7) adding the sample dropwise to the Mastersizer to achieve shading between 2-3 to analyze the particle size distribution described above.

In accordance with the present invention, the metal phosphate particles can be substantially milled so that more than 90% of the metal phosphate particles in the activating wash liquid composition are milled, for example, more than 91%, for example, more than 92%, such as more than 93 %, such as more than 94%, such as more than 95%, such as more than 96%, such as more than 97%, such as more than 98%, such as more than 99%. In accordance with the present invention, the metal phosphate particles can be completely milled, so that 100% of the particles are milled.

In accordance with the present invention, metal phosphate (as a common metal compound) may be present in the activating rinsing liquid in an amount of at least 50 ppm (ppm) based on the total mass of the rinsing activating liquid, such as at least 150 ppm, and in some cases, may be present in the activating rinsing liquid in an amount of not more than 5000 ppm, based on the total weight of the activating rinsing liquid, for example, not more than 1500 ppm. In accordance with the present invention, metal phosphate (as a general metal compound) may be present in the activating liquid for washing in an amount of from 50 parts per million to 5000 parts per million of total metal phosphate, based on the total weight of the activating liquid for washing, for example, 150 parts per million to 1,500 parts per million.

In accordance with the present invention, the divalent or trivalent metal phosphate metal may be zinc, iron, calcium, manganese, aluminum, nickel, or combinations thereof. If combinations of different metal phosphates are used, they can be the same or different metals and can be selected from the specific phosphates of zinc, iron, calcium, manganese and aluminum mentioned below.

Suitable zinc phosphates used in the wash bath solution (bath) include, but are not limited to, Zn ₃ (PO ₄ ) ₂ , Zn ₂ Fe (PO ₄ ) ₂ , Zn ₂ Ca (PO ₄ ) ₂ , Zn ₂ Mn ( PO ₄ ) ₂ or combinations thereof.

Suitable iron phosphates used in the solution with an activating washing liquid include, but are not limited to, FePO ₄ , Fe ₃ (PO ₄ ) _2, or combinations thereof.

Suitable calcium phosphates used in the solution with an activating rinse include, but are not limited to, CaHPO ₄ , Ca ₃ (PO ₄ ) _2, or combinations thereof.

Suitable manganese phosphates used in a solution with an activating wash liquid include, but are not limited to, Mn ₃ (PO ₄ ) ₂ , MnPO _4, or combinations thereof.

Suitable aluminum phosphates used in the solution with an activating wash liquid include, but are not limited to, AlPO ₄ .

In accordance with the present invention, the activating washing liquid may further comprise a dispersant. The dispersant may be ionic or non-ionic. Suitable ionic dispersants used in the activating solution for washing may contain an aromatic organic acid, a phenolic compound, a phenolic resin, or combinations thereof. Suitable non-ionic dispersants used in the activating liquid for washing may include non-ionic polymers, in particular those consisting of monomers (or their residues), including propylene oxide, ethylene oxide, styrene, a mono acid such as (meth) acrylic acid, a diacid, such such as maleic acid or itaconic acid, an acid anhydride such as acrylic anhydride or maleic anhydride, or combinations thereof. Examples of suitable commercially available non-ionic dispersants include DISPERBYK®-190, available from BYK-Chemie GmbH and ZetaSperse® 3100, available from Air Products Chemicals Inc.

In accordance with the present invention, the activating liquid for washing can be essentially free or completely free of ionic dispersants. As used in the present description, the activating liquid for washing essentially does not contain ionic dispersants, if ionic dispersants are present, then in an amount of less than 1% by weight based on the total weight of the activating liquid for washing. As used in the present description, the activating liquid for washing is completely free of ionic dispersants if ionic dispersants are absent in the activating liquid for washing, that is, 0% by weight based on the total weight of the activating liquid for washing.

In accordance with the present invention, the activating washing liquid may include a metal sulfate salt, such as, for example, where the metal phosphate particles have a particle size D ₉₀ greater than 1 μm to 10 μm or, for example, where the metal phosphate particles have a particle size D ₉₀ less than 1 micron. The metal sulfate metal may be the same or different from the metal particles of the metal phosphate. According to the present invention, the metal of the metal sulfate salt can be a divalent metal, a trivalent metal, or combinations thereof, such as, for example, nickel, copper, zinc, iron, magnesium, cobalt, aluminum, or combinations thereof.

In accordance with the present invention, if present, a sulfate ion of a metal sulfate salt may be present in the activating liquid for washing in an amount of at least 5 ppm based on the total weight of the activating liquid for washing, such as at least 10 parts per million, for example, at least 20 parts per million, for example, at least 50 parts per million, and in some cases not more than the solubility limit of the metal sulfate salt in the activating liquid for washing, such as e more than 5000 parts per million, such as not more than 1000 parts per million, for example, not more than 500 parts per million, for example, not more than 250 parts per million. In accordance with the present invention, the sulfate ion of the metal sulfate salt may be present in an amount of from 5 parts per million to 5000 parts per million, based on the total amount of sulfate in the metal sulfate salt, for example, from 10 parts per million to 1000 parts per million, for example, 20 ppm to 500 ppm, for example, from 50 ppm to 250 ppm. In accordance with the present invention, the activating washing liquid may be substantially free or, in some cases, completely free of sulfate ions. As used herein, with respect to a sulfate ion of a metal sulfate salt, the term “substantially free” means that the sulfate ion is present in the activating liquid for washing in an amount of less than 5 ppm based on the total weight of the activating liquid for washing. As used herein with respect to a sulfate ion of a metal sulfate salt, the term “completely free” means that the activating washing liquid does not contain a sulfate ion (that is, 0 parts per million sulfate ion (based on the total weight of the activating washing liquid), present in the activating liquid for washing).

In accordance with the present invention, the activating washing liquid may be in the form of a concentrate, where the concentrate has a viscosity sufficient to prevent the precipitation of particles of metal phosphate and metal sulfate salt (if present). According to the present invention, when used, the concentrated activating rinsing liquid may be diluted with water and / or an organic solvent.

In accordance with the present invention, the activating washing liquid may be a 1K composition (“one-component” or “one part”) or a multicomponent composition, such as, for example, a 2K composition (“two-component” or “two parts”). As defined herein, “1K” is a composition in which all ingredients can be premixed and stored. In contrast, a multicomponent composition is a composition in which at least two of the ingredients are stored separately and mixed together to form a solution (bath) for processing.

In accordance with the present invention, the activating washing liquid may be a 1K composition in which the 1K composition is formed from: a dispersion of divalent metal metal phosphate particles, trivalent metals or combinations thereof, metal phosphate particles have a particle size D _{90 of} not more than 10 μm; dispersant; and a metal sulfate salt (if present). Optionally, the 1K activating wash liquid may be a concentrate that is diluted to form a solution containing the activating wash liquid.

In accordance with the present invention, the activating washing liquid may be a 2K composition in which a dispersion of metal phosphate particles of divalent metals, trivalent metals, or combinations thereof, metal phosphate particles having a particle size of D ₉₀ which does not exceed 10 μm, and a dispersant form part of the first component. The metal sulfate salt may form part of the second component. Additional components containing any of the optional ingredients described below may also be added to the solution containing the activating rinse liquid. Any of the components of the activating washing liquid may be a concentrate that is diluted to form a solution containing the activating washing liquid.

In accordance with the present invention, the activating liquid for washing may include a wetting agent. In accordance with the present invention, wetting agents may be present in amounts of up to 2 weight percent, for example up to 0.5 weight percent, based on the total weight of the activating wash liquid. In some cases, wetting agents may be present in amounts of from 0.1 weight percent to 2 weight percent based on the total weight of the activating wash liquid, for example, 0.3 weight percent to 0.5 weight percent. As used herein, the term “wetting agent” reduces the surface tension at the interface between the particles of the dispersed phase and the aqueous medium to allow the aqueous medium to more uniformly contact or “wet” the surface of the particles of the dispersed phase.

In accordance with the present invention, the activating rinsing liquid may have a pH of from 6 to 12, for example from 6.5 to 9, for example from 7.5 to 8.5, for example from 7 to 8. In the activating rinsing liquid may be alkaline component in an amount sufficient to adjust the pH of the activating liquid for washing. Suitable alkaline components may include, for example, sodium hydroxide, sodium carbonate, sodium tripolyphosphate, potassium orthophosphate, or combinations thereof.

In accordance with the present invention, the activating liquid for washing may also include a biocide. Suitable biocides include, for example, methylchloroisothiazolinone, methylisothiazolinone, or combinations thereof. When used, the biocide may be present in an amount of at least 10 parts per million based on the active substance in the activating liquid for washing, such as at least 20 parts per million, for example, at least 80 parts per million, for example, at least 100 parts per million, and in some cases, not more than 140 parts per million, for example, not more than 120 parts per million, for example, not more than 40 parts per million, for example not more than 30 parts per million. In accordance with the present invention, the biocide may be present in an amount of from 10 parts per million to 140 parts per million based on the active substance, for example from 10 parts per million to 40 parts per million, for example, from 20 parts per million to 30 parts per million for example, from 80 parts per million to 140 parts per million, from 100 parts per million to 120 parts per million. The person skilled in the art understands that biocides can be included in the activating liquid for washing in amounts based on the manufacturer's instructions.

In accordance with the present invention, the activating washing liquid may further comprise silicon dioxide. In accordance with the present invention, the silica may be precipitated silica, such as synthetic amorphous precipitated silica. In accordance with the present invention, silicon dioxide may be brittle under shear. As used herein, the term “shear brittle” means that the particle size can be reduced by shear. In accordance with the present invention, silica may contain, for example, Hi-Sil ™ EZ 160G silica (commercially available from PPG Industries, Inc.). In accordance with the present invention, if present, silicon dioxide may be present in an amount of at least 50 ppm based on the total weight of the activating wash liquid, such as at least 100 ppm, for example at least 150 parts per million, and in some cases, not more than 5000 parts per million, based on the total weight of the activating liquid for washing, for example, not more than 1000 parts per million, for example, not more than 500 parts per million. In accordance with the present invention, silicon dioxide may be present in the activating liquid for washing in an amount of from 50 parts per million to 5000 parts per million, based on the total weight of the activating liquid for washing, for example, from 100 parts per million to 1000 parts per million, for example, from 150 parts per million to 500 parts per million.

The activating washing liquid may optionally contain components in addition to the dispersant (i.e., components other than the dispersing agent), such as nonionic surfactants and excipients commonly used in the art. Such additional optional components include surfactants that function as antifoam agents. Amphoteric and / or nonionic surfactants may be used. Foaming surfactants may be present, if at all, in amounts of at least 0.1 weight percent, based on the total weight of the solution with an activating rinse liquid, such as at least 0.5 weight percent, and in some cases, may be present in amounts of not more than 1 weight percent, for example, not more than 0.7 weight percent, based on the total weight of the solution with the activating washing liquid. In some cases, antifoaming surfactants may be present, if at all, in amounts from 0.1 weight percent to 1 weight percent, for example, from 0.5 weight percent to 0.7 weight percent, based on the total weight of the solution with activating liquid for washing.

According to the present invention, the activating rinse liquid may further comprise a rheology modifier in addition to a dispersant (i.e., different from the dispersant). The rheology modifier may include, for example, polyurethanes, acrylic polymers, lattices, styrene / butadiene, polyvinyl alcohols, clays such as attapulgite, bentonite and other montmorillonite, cellulose-based materials such as carboxylmethyl cellulose, methyl cellulose, ( methyl cellulose or gelatin; resins such as guar and xanthan gums, or combinations thereof.

In accordance with the present invention, the activating liquid for washing can be essentially or, in some cases, completely free of titanium phosphate particles. As used herein, the term “substantially free” when used with respect to the absence of titanium phosphate particles in an activating washing liquid means that any titanium phosphate particles present in the activating washing liquid are not specifically added and they are present in a trace amount of less than 5 parts per million, based on the total weight of the activating liquid for washing. As used herein, the term “completely free” when used with respect to the absence of titanium phosphate particles means that there are no titanium phosphate particles at all.

The activating rinse liquid of the present invention can be freshly prepared with the above ingredients at the indicated concentrations or can be obtained as aqueous concentrates in which the concentration of the various ingredients is much higher, so that the concentrates can be diluted with an aqueous medium such as water, or diluted by feeding them into an activating bath containing an activating rinsing liquid that has been used for some time.

In accordance with the present invention, the solution with the activating liquid for washing may contain a chelating agent. The chelating agent may contain, for example, carboxylates, such as tartrates, citrates or gluconates, acetate-based complexes, such as ethylene diamine tetraacetate or nitrilotriacetate, phosphates such as penta sodium triphosphate or tetracal pyrophosphate, phosphonates, polycarboxylates, salts or esters of the above their combinations.

The present invention may also be a method of treating a substrate, comprising contacting at least a portion of the surface of the substrate with an activating washing liquid, which is disclosed herein. The method may further include contacting at least a portion of the surface of the substrate that has been brought into contact with the activating liquid for washing with the composition for pretreatment with metal phosphate.

Optionally, the surface of the substrate to be treated in accordance with the methods of the present invention can be cleaned to remove grease, dirt or other foreign matter and / or washed before applying the activating liquid for washing. Substrate surface cleaning is often performed using mild or strong alkaline cleaners, such as those commercially available and commonly used in metal pretreatment processes. Examples of alkaline cleaners suitable for use in the present invention include Chemkleen ™ 163, Chemkleen ™ 177, Chemkleen ™ 181ALP, Chemkleen ™ 490MX and Chemkleen ™ 2010LP, all of which are commercially available from PPG Industries, Inc.

After cleaning, the substrate may optionally be washed with tap water, deionized water and / or an aqueous solution of washing agents to remove any residues. The wet surface of the substrate can optionally be dried, for example, dried in air, for example, using an air knife or a blower with warm air.

In accordance with the present invention, an activating washing liquid may be applied to the surface of a substrate by spraying, roll coating, or dipping methods. The washing activating liquid may be applied to the substrate at a temperature of, for example, from 15 ° C to 50 ° C, for example from 25 ° C to 35 ° C, for any suitable period of time, for example at least 1 second, for example, at least 10 seconds, for example at least 2 minutes, for example at least 5 minutes.

In accordance with the present invention, the substrate treatment method may further include contacting at least a portion of the surface that has been brought into contact with the activating rinse liquid with a metal phosphate pretreatment composition, such as a pretreatment composition with zinc phosphate to form a phosphate coating on the surface of the "activated" substrate. As used herein, the term “pretreatment composition” refers to a composition which, upon contact with the substrate, interacts with and chemically changes the surface of the substrate and binds to it, forming a protective layer and which contains zinc, iron phosphates and / or other divalent metals known in this areas of technology.

In accordance with the present invention, the pretreatment composition may contain zinc ions and phosphate ions. In accordance with the present invention, the content of zinc ions in the pretreatment composition may be at least 500 ppm based on the total weight of the pretreatment composition, such as at least 800 ppm, and in some cases may be no more than 1500 ppm based on the total weight of the pretreatment composition, such as no more than 1200 ppm. In accordance with the present invention, the content of zinc ions in aqueous acidic compositions can range from 500 ppm to 1,500 ppm based on the total weight of the pretreatment composition, such as at least 800 ppm to 1,200 ppm million. The source of zinc ion can be conventional sources of zinc ions, such as zinc nitrate, zinc oxide, zinc carbonate, zinc metal and the like.

In accordance with the present invention, the phosphate content in the pretreatment composition may be at least 8000 ppm based on the total weight of the pretreatment composition, such as at least 12000 ppm, and in some cases may be not more than 20,000 ppm based on the total weight of the pretreatment composition, such as not more than 14,000 ppm. According to the present invention, the phosphate content of the pretreatment composition may be from 8000 ppm to 20,000 ppm based on the total weight of the pretreatment composition, such as from 12,000 ppm to 14,000 ppm. The source of the phosphate ion may be phosphoric acid, monosodium phosphate, disodium phosphate and the like.

The pretreatment composition of the present invention may have a pH of at least 2.5, for example at least 3.0, and in some cases, not more than 5.5, for example, not more than 3.5. The pretreatment composition may have a pH of from 2.5 to 5.5, for example, from 3.0 to 3.5.

In accordance with the present invention, the composition for pre-treatment may also contain an accelerator. The accelerator may be present in an amount sufficient to accelerate the formation of zinc phosphate coating and may be present in the pretreatment composition in an amount of at least 500 ppm based on the total weight of the pretreatment composition, such as at least 1000 parts per million, such as at least 2500 parts per million, and in some cases may be present in an amount of not more than 20,000 parts per million, based on the total weight of the pretreatment composition and, for example, no more than 10,000 ppm, for example, no more than 5,000 parts per million. In accordance with the present invention, the accelerator may be present in the pretreatment composition in an amount of from 500 ppm to 20,000 ppm based on the total weight of the pretreatment composition, for example, from 1000 to 10,000 ppm, for example, from 2500 ppm to 5,000 ppm. Accelerators used may include oximes such as acetaldehyde oxime and acetoxime, nitrites such as sodium nitrite and ammonium nitrite, peroxides such as hydrogen peroxide, or combinations thereof.

In accordance with the present invention, the pretreatment composition may also contain fluoride ion, nitrate ion and various metal ions such as nickel ion, cobalt ion, calcium ion, magnesium ion, manganese ion, iron ion, copper ion and the like.

Fluoride ion may be present in the pretreatment composition in an amount of at least 100 ppm based on the total weight of the pretreatment composition, such as at least 250 ppm, and in some cases, may be present in an amount of not more than than 2500 ppm, based on the total weight of the pretreatment composition, such as not more than 1000 ppm, and in some cases may be present in an amount from 100 ppm to 2500 ppm You weigh the total weight of the pretreatment composition, such as 250 ppm to 1000 ppm.

In accordance with the present invention, a nitrate ion may be present in the pretreatment composition in an amount of at least 1000 ppm based on the total weight of the pretreatment composition, such as at least 2000 ppm, and in some cases may be present in an amount of not more than 10,000 ppm, based on the total weight of the pretreatment composition, such as not more than 5,000 ppm, and in some cases may be present in an amount of 1000 h stey per million to 10,000 parts per million based on the total weight of the pretreatment composition, such as 2000 ppm to 5000 ppm.

According to the present invention, nickel ion may be present in the pretreatment composition in an amount of at least 100 ppm based on the total weight of the pretreatment composition, such as at least 200 ppm, for example at least at least 300 ppm, and in some cases, may be present in the pretreatment composition in an amount of not more than 1800 ppm, for example not more than 1200 ppm, for example not more than 800 ppm and in some cases, may be present in the pretreatment composition in an amount of from 100 ppm to 1800 ppm, based on the total weight of the pretreatment composition, for example from 200 ppm to 1200 ppm, for example from 300 parts per million to 800 parts per million.

In accordance with the present invention, calcium ion may be present in the pretreatment composition in an amount of at least 100 ppm based on the total weight of the pretreatment composition, such as at least 500 ppm, and in some cases, not more than than 4000 ppm, based on the total weight of the pretreatment composition, such as not more than 2500 ppm, and in some cases may be present in an amount of from 100 ppm to 4000 ppm based on the total weight of the pretreatment composition, such as 500 ppm to 2500 ppm.

According to the present invention, a manganese ion may be present in the pretreatment composition in an amount of at least 100 ppm based on the total weight of the pretreatment composition, such as at least 200 ppm, for example at least at least 500 ppm, and in some cases not more than 1500 ppm, based on the total weight of the pretreatment composition, such as not more than 1000 ppm, for example, not more than 800 ppm, and in some oryh cases in an amount of from 100 ppm to 1500 ppm, based on the total weight of the pretreatment composition, such as from 200 ppm to 1000 ppm, e.g., from 500 ppm to 800 ppm.

In accordance with the present invention, an iron ion may be present in the pretreatment composition in an amount of at least 5 ppm based on the total weight of the pretreatment composition, such as at least 50 ppm, and in some cases, not more than than 500 ppm, based on the total weight of the pretreatment composition, such as not more than 300 ppm, and in some cases may be present in the pretreatment composition in an amount of 5 hours or more tei per million up to 500 parts per million, for example, from 50 parts per million to 300 parts per million.

In accordance with the present invention, a copper ion may be present in the pretreatment composition in an amount of at least 1 ppm based on the total weight of the pretreatment composition, such as at least 3 ppm, and in some cases, not more than than 30 ppm, based on the total weight of the pretreatment composition, such as not more than 15 ppm, and in some cases may be present in the pretreatment composition in an amount of 1 ppm Llion.

The pretreatment composition of the present invention can be obtained fresh with the above ingredients at the indicated concentrations, or can be prepared as aqueous concentrates in which the concentration of the various ingredients is much higher, so that the concentrates can be diluted with an aqueous medium such as water, or diluted by feeding them into a zinc phosphating composition that has been used for some time. Typical concentrates may contain at least 10,000 parts per million zinc ions based on the total weight of the concentrate of the pretreatment composition, such as at least 12,000 parts per million zinc ions, such as at least 16,000 parts per million zinc ions and, in some cases, may contain no more than 100,000 parts per million zinc ions, based on the total weight of the concentrate of the pretreatment composition, such as not more than 30,000 parts per million zinc ions, such as not more than 20,000 parts per a million zinc ions, and in some cases may contain from 10,000 parts per million to 100,000 parts per million zinc ions, calculated on the total weight of the pretreatment composition concentrate, for example from 12,000 parts per million to 30,000 parts per million zinc ions, for example 16,000 ppm to 20,000 ppm zinc ions.

The metal phosphate pretreatment composition can be applied to the activated substrate by spraying or immersing the activated substrate in a phosphate bath containing the composition at a temperature typically from 20 ° C. to 75 ° C., typically for 1-3 minutes. The bath may typically be an acidic phosphate bath and may contain iron and / or other divalent metals known in the art, in addition to zinc ions, as discussed above.

After the phosphate coating is applied, the substrate may be optionally washed with a chromium solution or chromium-free, optionally washed with water and / or optionally dried. Paint can then be applied if necessary, for example, by electrodeposition or using conventional spray or roller coating methods.

The present invention is also directed to a substrate treated with a pre-treatment system, which is disclosed here. The substrate may contain nucleation sites formed from the activating washing liquid described above, and may further comprise a metallophosphate coating obtained from the metal phosphate pretreatment composition described above applied to the nucleation sites formed on at least a portion of the substrate by activating liquid for washing. The metal phosphate coating may contain crystals having a crystal size of at least 0.4 μm, such as at least 0.5 μm, such as at least 0.6 μm, such as at least 0.9 microns, and in some cases not more than 4 microns, such as not more than 2.7 microns, for example, not more than 2.5 microns, for example, not more than 2 microns. The metal phosphate coating may contain crystals having a crystal size from 0.4 μm to 4 μm, for example, from 0.5 μm to 2.5 μm, for example, from 0.6 μm to 2 μm.

The crystal size of the phosphate coating can be determined by methods known to those skilled in the art. For example, a representative panel area can be selected (i.e., a covered area of about 1.27 cm by 1.27 cm without visible coating defects), and a representative area image can be obtained either at 5,000 or 10,000 magnification using a scanning electron microscope (SEM), such as, for example, Tescan Vega 2 SEM. The magnification used will depend on the size of the crystal, since a high magnification (10,000th) will be required for crystal sizes that cannot be distinguished at 5000x magnification using SEM. Nine to twelve equally spaced crystals, for example ten in each image, can be measured using software known to those skilled in the art, such as ImageJ (version 1.46), and typical crystal sizes can be averaged to determine crystal size . One skilled in the art will understand that there may be variations in this procedure that retain the essential elements of the microscopic image and averaging a representative crystal size.

The present invention also relates to an activation step, such as those used in the automotive industry. In accordance with the present invention, the activating step comprises immersing the substrate in a bath that contains an activating washing liquid, which is disclosed herein. In accordance with the present invention, the activating liquid for washing is contained inside the immersion tank at a temperature of from 15 ° C to 50 ° C. At least a portion of the surface of the substrate is contacted with an activating rinse liquid by immersing the substrate in an activating rinse liquid for any suitable period of time, such as those already described above. After immersion in the activating rinse liquid, a portion of the activated support can then be subjected to a phosphating step by applying a metal phosphate pretreatment composition, for example a zinc phosphate pretreatment composition, to the activated substrate. However, it should be noted that prior to applying the metal phosphate pretreatment composition to the activated substrate, additional activating washing liquid may be sprayed onto a portion of the activated substrate through a spray nozzle when the activated substrate is removed from the immersion tank. For example, the spray nozzle may be a spray nozzle nozzle that is located downstream of the immersion tank. After the activated substrate leaves the immersion tank and / or after the additional activating washing liquid is applied to the activated substrate, the activated substrate is phosphated by applying a metal phosphate pretreatment composition to the activated substrate using methods known in the art, such as spray and / or immersion method.

In accordance with the present invention, the activation step may comprise a series of spray nozzles that are used to apply the activating wash bath to at least a portion of the substrate. Underneath the spray nozzles, there is a spray tank that is designed to collect an activating washing liquid that exits the spray nozzles and / or any excess activating washing liquid that drains from the surface of the activated substrate. The spray tank is connected to the spray nozzles so that the spray nozzles use an activating rinse liquid that is collected in the spray tank, thereby recirculating the solution with an activating rinse liquid (activating rinse bath). After an activating rinse is applied to at least a portion of the substrate, the activated substrate is then phosphated as described in the previous paragraph.

According to the present invention, after the substrate is in contact with the pre-treatment composition, the coating composition containing the film-forming resin can be applied to at least a portion of the surface of the substrate that has been brought into contact with the pre-treatment composition. Any suitable technique can be used to apply such a coating composition to a substrate, including, for example, cleaning, dipping, flow coating, spraying, and the like. However, in some cases, as described in more detail below, such a coating composition may include an electrodeposition step in which the electrodepositable composition is deposited onto a metal substrate by electrodeposition. In some other cases, as described in more detail below, such a coating composition comprises a powder coating step. In other instances, the coating composition may be a liquid coating composition.

In accordance with the present invention, the coating composition may comprise a thermosetting film-forming resin or a thermoplastic film-forming resin. As used herein, the term “film-forming resin” refers to resins that can form a self-supporting continuous film on at least the horizontal surface of the substrate by removing any diluents or carriers present in the composition or by curing at ambient temperature or elevated temperature. Conventional film-forming resins that can be used include, but are not limited to, those commonly used in automotive OEM coating compositions, automotive coating compositions, industrial coating compositions, architectural coating compositions, tape coating compositions, and compositions aerospace coating, among others. As used herein, the term “thermosetting” refers to resins that “harden” irreversibly upon curing or crosslinking, the polymer chains of the polymer components being joined together by covalent bonds. This property is usually associated with the crosslinking reaction of the components of the composition, often caused, for example, by heat or radiation. Curing or crosslinking reactions can also be carried out under ambient conditions. After curing or crosslinking, the thermosetting resin will not melt when heat is applied and is insoluble in solvents. As used herein, the term “thermoplastic” refers to resins that contain polymer components that are not covalently bonded and thus can undergo a fluid stream when heated and are soluble in solvents.

As indicated, previously, according to the present invention, a coating composition containing a film-forming resin can be applied to the substrate using the electrodeposition coating step, where the electrodepositable composition is deposited on a metal substrate by electrodeposition. During the electrodeposition process, the treated metal substrate serving as the electrode and the electrically conductive counter electrode are placed in contact with the ionic electrodepositable composition. With the passage of electric current between the electrode and the counter electrode, when they are in contact with the electrodepositable composition, the adjacent film of the electrodepositable composition will be deposited substantially continuously on the metal substrate.

In accordance with the present invention, such electrodeposition can be performed at a constant voltage in the range from 1 volt to several thousand volts, usually from 50 to 500 volts. The current density is usually between 1.0 amperes and 15 amperes per square foot (10.8 to 161.5 amperes per square meter) and typically decreases rapidly during the electrodeposition process, which indicates the formation of a continuous self-insulating film.

According to the present invention, the electrodepositable coating composition may comprise a resinous phase dispersed in an aqueous medium, wherein the resinous phase comprises: (a) an ionic electrodepositable resin containing an active hydrogen group, and (b) a curing agent having functional groups reactive with active hydrogen groups (a).

In accordance with the present invention, electrodepositable compositions may, for example, comprise an active hydrogen-containing ionic, often cationic, electrodepositable resin as the main film-forming polymer. A wide variety of electrodepositable film-forming resins are known and can be used in the present invention as long as the polymers are "water dispersible", that is, adapted to solubilize, disperse or emulsify in water. The water-dispersible polymer is ionic in nature, that is, the polymer will contain anionic functional groups to impart a negative charge, or may contain cationic functional groups to impart a positive charge.

Examples of film-forming resins suitable for use in anionic electrodepositable coating compositions are base solubilized carboxylic acid-containing polymers, such as a reaction product or an adduct of a dry oil or semi-dry fatty acid ester with dicarboxylic acid or anhydride; and the reaction product of an ester of a fatty acid, unsaturated acid or anhydride and any further unsaturated modifying materials, which are further reacted with a polyol. At least partially neutralized interpolymers of hydroxyalkyl esters of unsaturated carboxylic acids, unsaturated carboxylic acid and at least one other ethylenically unsaturated monomer are also suitable. Another suitable electrodepositable film-forming resin comprises an alkyd-aminoplast carrier, i.e., a carrier containing an alkyd resin and an amine-aldehyde resin. Another anionic electrodepositable resin composition includes resinous polyol mixed esters, such as those described in US Pat. No. 3,749,657 in column 9, lines 1 to 75 and column 10, lines 1 to 13, a portion of which is incorporated herein by reference. Other acid-functional polymers, such as phosphatized polyepoxide or phosphated acrylic polymers known to those skilled in the art, may also be used.

As indicated above, it is often desirable that an ionic electrodepositable resin containing active hydrogen atoms (a) be cationic and capable of being deposited on the cathode. Examples of such cationic film-forming resins include resins containing an amine salt group, such as acid solubilized reaction products of polyepoxides and primary or secondary amines, such as those described in US Pat. Nos. 3,663,389; 3,984,299; 3,947,338; and 3947339. Often these resins containing an amine salt group are used in combination with a blocked isocyanate curing agent. The isocyanate can be completely blocked, as described in US patent No. 3984299, or the isocyanate can be partially blocked and exposed to the skeleton of the polymer, as described in US patent No. 3947338. Also, as a film-forming resin can be used one-component compositions described in US patent 4134866 and DE-OS No. 2707,405. In addition to the reaction products of epoxy amine, film-forming resins can also be selected from cationic acrylic resins, such as those described in US Pat. Nos. 3,455,806 and 3,928,157.

In addition to a resin containing an amine salt group, resins containing a quaternary ammonium salt group can also be used, such as those formed by reacting an organic polyepoxide with a tertiary amine salt, as described in US Patent Nos. 3,962,165; 3,975,346; and 4001101. Examples of other cationic resins are resins containing a triple sulfonium salt group and resins containing quaternary phosphonium salt groups, such as those described in US Pat. Nos. 3,793,278 and 3,984,922, respectively. Film-forming resins that can be cured by transesterification, for example, described in European Application No. 12463, can also be used. In addition, cationic compositions obtained from Mannich bases, for example, described in US Pat. No. 4,141,432, can be used.

In accordance with the present invention, the resins present in the electrodepositable composition are positively charged resins that contain primary and / or secondary amino groups, such as those described in US Pat. Nos. 3,663,389; 3,947,339; and 4116900. In US Pat. No. 3,947,339, a polyketimine derivative of a polyamine, such as diethylene triamine or triethylenetetraamine, is reacted with a polyepoxide. When the reaction product is neutralized with acid and dispersed in water, free primary amino groups are formed. In addition, equivalent products are formed by reacting the polyepoxide with excess polyamines, such as diethylene triamine and triethylenetetraamine, and the excess polyamine vacuum is distilled off from the reaction mixture as described in US Pat. Nos. 3, 663, 389 and 4,116,900.

According to the present invention, an active hydrogen ion-containing electrodepositable resin may be present in the electrodepositable composition in an amount of from 1 to 60 weight percent, for example, from 5 to 25 weight percent, based on the total weight of the electrodeposition bath.

As indicated, the resinous phase of the electrodepositable composition often often further comprises a curing agent adapted to react with the active hydrogen groups of the ionic electrodepositable resin. For example, both blocked organic polyisocyanate and amino resin hardeners are suitable for use in the present invention.

Amino resins can be used as a hardener for anionic electrodeposition, are condensation products of amines or amides with aldehydes. Examples of suitable amines or amides are melamine, benzoguanamine, urea and the like. The aldehyde used is typically formaldehyde, although products can be obtained from other aldehydes such as acetaldehyde and furfural. The condensation products contain methylol groups or similar alkylol groups, depending on the particular aldehyde used. Often these methylol groups are esterified by reaction with an alcohol, such as a monohydric alcohol containing from 1 to 4 carbon atoms, such as methanol, ethanol, isopropanol and n-butanol. Amino resins are commercially available from American Cyanamid Co. under the brand name CYMEL and from Monsanto Chemical Co. under the brand name RESIMENE.

Amino resin hardeners are often used in combination with an anionic electrodepositable resin containing active hydrogen in amounts from 5 percent to 60 percent by weight, for example, from 20 percent to 40 percent by weight, percent of the total weight of the solids of the resin in the electrodepositable composition. As indicated, blocked organic polyisocyanates are often used as a hardener in cathodic electrodeposition compositions. Polyisocyanates can be completely blocked, as described in US patent No. 3984299 in count. 1, line 1 - 68, count. 2 and count 3, lines 1-15 or partially blocked and react with a polymer base, as described in US patent No. 3947338, in col. 2, line 65 to 68, count. 3 and count 4 line from 1 to 30, the parts of which are incorporated here by reference. By "blocked" is meant that the isocyanate groups are reacted with the compound, so that the resulting blocked isocyanate group is resistant to active hydrogen atoms at ambient temperature, but reactive with active hydrogen atoms in a film-forming polymer at elevated temperatures, usually between 90 ° C and 200 ° FROM.

Suitable polyisocyanates include aromatic and aliphatic polyisocyanates, including cycloaliphatic polyisocyanates, and typical examples include diphenylmethane-4,4'-diisocyanate (MDI), 2,4- or 2,6-toluene diisocyanate (TDI), including mixtures thereof, p-phenylenediisocyanate, tetramethylene and hexamethylene diisocyanates, dicyclohexylmethane-4,4'-diisocyanate, isophorone diisocyanate, a mixture of phenylmethane-4,4'-diisocyanate and polymethylene polyphenyl isocyanate. Higher polyisocyanates, such as triisocyanates, may be used. An example may include triphenylmethane-4,4 ', 4' 'thioisocyanate. Can also be used isocyanate prepolymers with polyols such as neopentyl glycol and trimethylolpropane, and with polymer polyols such as polycaprolactone diols and triols (equivalent NCO / OH ratio greater than 1).

Polyisocyanate curing agents are usually used in combination with a cationic electrodepositable resin containing active hydrogen in amounts of from 5 percent to 60 percent by weight, for example, from 20 percent to 50 percent by weight, percent of the total solids of the resin of the electrodepositable composition.

The electrodepositable coating compositions described herein may in particular be in the form of an aqueous dispersion. The average particle size of the resinous phase is usually less than 1.0 microns and usually less than 0.5 microns, often less than 0.15 microns.

The concentration of the resinous phase in the aqueous medium is often at least 1 percent by weight, for example, from 2 to 60 percent by weight, based on the total weight of the aqueous dispersion. When such coating compositions are in the form of resin concentrates, they typically have a resin solids content of from 20 to 60 percent by weight, based on the weight of the aqueous dispersion.

The electrodepositable coating compositions described herein are often supplied in two components: (1) a starting pure resin, which typically includes an active hydrogen ion-deposited electrodepositable resin, i.e., a base film-forming polymer, a curing agent, and any additional water-dispersible, non-pigmented components ; and (2) a pigment paste, which typically includes one or more dyes (described below), a water-dispersible, ground resin, which may be the same or different from the base film-forming polymer, and optionally additives, such as wetting or dispersing additives. The electrodeposition bath components (1) and (2) are dispersed in an aqueous medium that contains water and, as a rule, coalescing solvents.

As mentioned above, in addition to water, the aqueous medium may contain a coalescing solvent. Useful coalescing solvents are often hydrocarbons, alcohols, esters, ethers and ketones. Coalescing solvents that can be used can be alcohols, polyols and ketones. Specific coalescing solvents include isopropanol, butanol, 2-ethylhexanol, isophorone, 2-methoxypentanone, ethylene and propylene glycol and monoethyl monobutyl and monohexyl ethers of ethylene glycol. The amount of coalescing solvent is usually from 0.01 to 25 percent, for example, from 0.05 to 5 percent by weight, based on the total weight of the aqueous medium.

After deposition of the electrodepositable coating composition, the coating is often heated to cure the deposited composition. The heating or curing operation is often carried out at a temperature in the range from 120 to 250 ° C, for example, from 120 to 190 ° C, for a period of time from 10 to 60 minutes. According to the invention, the thickness of the resulting film is from 10 to 50 microns.

Alternatively, as described above, according to the present invention, after the substrate has been brought into contact with the pretreatment composition, the powder coating composition can then be applied to at least a portion of the surface of the substrate that has been brought into contact with the composition pretreatment. The term “powder coating composition” as used herein refers to a coating composition that is completely free of water and / or solvent. Accordingly, the powder coating composition disclosed herein is not equivalent to water-based and / or solvent-based coating compositions known in the art.

According to the present invention, the powder coating composition comprises (a) a film-forming polymer having a reactive functional group; and (b) a curing agent that reacts with a functional group. Examples of powder coating compositions that can be used in the present invention include the ENVIROCRON line of polyester powder coating compositions (commercially available from PPG Industries, Inc.) or an epoxy polyester hybrid powder coating composition. Alternative examples of powder coating compositions that can be used in the present invention include low temperature curing of thermosetting powder coating compositions containing (a) at least one tertiary amine urea compound, at least one tertiary aminourethane compound or mixtures thereof, and ( b) at least one film-forming epoxy resin and / or at least one siloxane resin (such as those described in US Pat. No. 7,470,752 referred to by PPG Industries, Inc. and incorporated here by reference); curable powder coating compositions essentially containing (a) at least one tertiary amine urea compound, at least one tertiary aminourethane compound or mixtures thereof, and (b) at least one film-forming epoxy resin and / or at least one siloxane-containing compound resins (such as those described in US Pat. No. 7,432,333 assigned to PPG Industries, Inc. and incorporated herein by reference); and compounds containing a solid powder mixture of a polymer containing a reactive group having a Tg of at least 30 ° C (for example, described in US Pat. No. 6,797,387, referred to PPG Industries, Inc. and incorporated herein by reference).

Suitable film-forming polymers that can be used in the powder coating composition of the present invention include (poly) ester (e.g., triglycidyl isocyanurate polyester), (poly) urethane, isocyanurate, (poly) urea, (poly) epoxide, anhydride, acrylic polymer, (poly) ether, (poly) sulfide, (poly) amine, (poly) amide, (poly) vinyl chloride, (poly) olefin, (poly) vinylidene fluoride, or combinations thereof.

According to the present invention, the reactive functional group of the film-forming polymer of the powder coating composition comprises hydroxyl, carboxyl, isocyanate (including blocked (poly) isocyanate), primary amine, secondary amine, amide, carbamate, urea, urethane, vinyl, unsaturated ester, maleimide , fumarate, anhydride, hydroxylalkylamide, epoxide, or combinations thereof.

Suitable curing agents (crosslinking agents) that can be used in the powder coating composition of the present invention include an amino resin, a polyisocyanate, a blocked polyisocyanate, a polyepoxide, a polyacid, a polyol, or combinations thereof.

After a powder coating is applied to the surface of the composition, the coating is often heated to cure the deposited composition. The heating or curing operation is often carried out at a temperature in the range from 150 ° C to 200 ° C, for example, from 170 ° C to 190 ° C, for a period of time from 10 to 20 minutes. According to the invention, the thickness of the obtained film is from 50 microns to 125 microns.

As mentioned above, the coating composition may be a liquid coating composition. As used herein, the term “liquid coating composition” refers to a coating composition that contains a portion of water and / or a solvent. Accordingly, the liquid coating composition described herein is equivalent to water-based and / or solvent-based coating compositions known in the art.

As indicated above, in accordance with the present invention, the coating composition may be a composition for liquid coating. As used herein, the term “liquid coating composition” refers to a coating composition that contains a portion of water and / or a solvent. Accordingly, the composition for liquid coating described herein is equivalent to water-based and / or solvent-based coating compositions known in the art.

In accordance with the present invention, a composition for liquid coating may contain, for example, (a) a film-forming polymer having a reactive functional group; and (b) a curing agent that reacts with a functional group. In other examples, the liquid coating may contain a film-forming polymer that can react with oxygen in air or coalesce (coagulate) into the film by evaporating water and / or solvents. These film formation mechanisms may require or be accelerated by the use of heat or some type of radiation, such as ultraviolet or infrared. Examples of liquid coating compositions that can be used in the present invention include SPECTRACRON® solvent-based coating compositions, AQUACRON® water-based coating compositions, and RAYCRON® ultraviolet-cured coatings (all commercially available from PPG Industries, Inc. )

Suitable film-forming polymers that can be used in the liquid coating composition of the present invention may contain (poly) ester, alkyd, (poly) urethane, isocyanurate, (poly) urea, (poly) epoxide, anhydride, acrylic polymer, simple (poly) ether, (poly) sulfide, (poly) amine, (poly) amide, (poly) vinyl chloride, (poly) olefin, (poly) vinylidene fluoride, (poly) siloxane, or combinations thereof.

In accordance with the present invention, the reactive functional group of the film-forming polymer of the liquid coating composition may comprise hydroxyl, carboxyl, isocyanate (including blocked (poly) isocyanate), primary amine, secondary amine, amide, carbamate, urea, urethane, vinyl, unsaturated ester , maleimide, fumarate, anhydride, hydroxylalkylamide, epoxide, or combinations thereof.

Suitable curing agents (crosslinking agents) that can be used in the liquid coating composition of the present invention may include an amino resin, a polyisocyanate, a blocked polyisocyanate, a polyepoxide, a polyacid, a polyol, or combinations thereof.

In addition, a colorant and, if desired, various additives, such as surfactants, wetting agents, or a catalyst, may be included in the coating composition (electrodepositable, powder, or liquid). As used herein, the term “colorant” means any substance that imparts a color and / or other opacity and / or other visual effect to the composition. The dye may be added to the composition in any suitable form, such as discrete particles, dispersions, solutions and / or flakes. One colorant or a mixture of two or more colorants may be used.

Examples of dyes include pigments, dyes and shades, such as those used in the paint industry and / or listed in the Association of manufacturers of dry flowers / Dry Color Manufacturers Association (DCMA), as well as compositions with special effects. The colorant may include, for example, a finely divided solid powder that is insoluble but wettable under conditions of use. The colorant may be organic or inorganic and may be agglomerated or non-agglomerated. Dyes can be incorporated using a ground carrier, such as an acrylic grinding carrier, the use of which will be known to one skilled in the art.

Examples of pigments and / or pigment compositions include, but are not limited to, the crude pigment carbazole dioxazine, azo, monoazo, disazo, naphthol AS, salt type (lakes), benzimidazolone, condensation, metal complex, isoindolinone, isoindoline and polycyclic phthalocyanine, x perylene, peinone, diketopyrrolopyrrol, thioindigo, anthraquinone, indantrone, anthrapyrimidine, flavantrone, pyrantron, anthantrone, dioxazine, triarylarbonium, quinophthalone pigments, diketopyrrolopyrrole red (DPPBO red), and titanium dioxide, and The terms “pigment” and “color filler” may be used interchangeably.

Examples of dyes include, but are not limited to, those that are solvent-based and / or water-based, such as phthalo green or blue, iron oxide, bismuth vanadate, anthraquinone, perylene, aluminum, and quinacridone.

Examples of shades include, but are not limited to, pigments dispersed on water-based media or miscible with water, such as AQUA-CHEM 896, commercially available from Degussa, Inc., CHARISMA COLORANTS and MAXITONER INDUSTRIAL COLORANTS, commercially available from Accurate Dispesions Eastman Chemical, Inc.

As noted above, the dye may be in the form of a dispersion, including (but not limited to) a dispersion of nanoparticles. Nanoparticle dispersions can include one or more finely divided nanoparticles and / or dyes that provide the desired visible color and / or opacity and / or visual effect. Nanoparticle dispersions may include dyes, such as pigments or dyes, having a particle size of less than 150 nm, for example, less than 70 nm or less than 30 nm. Nanoparticles can be obtained by grinding organic or inorganic pigments with grinding media having a particle size of less than 0.5 mm. Examples of dispersions of nanoparticles and methods for their preparation are identified in US patent No. 6,875,800 B2, which is incorporated here by reference. Dispersions of nanoparticles can also be obtained by crystallization, precipitation, gas-phase condensation, and chemical abrasion (i.e., partial dissolution). To minimize re-agglomeration of nanoparticles within the coating, a dispersion of resin coated nanoparticles can be used. As used herein, the term “resin coated nanoparticle dispersion” refers to a continuous phase in which latent “composite microparticles” are dispersed that contain a nanoparticle and a polymer coating on the nanoparticle. Examples of dispersions of resin coated nanoparticles and methods for their preparation are identified in US Patent Application Publication 2005-0287348 A1, filed June 24, 2004, US Provisional Application No. 60 / 482,167, filed June 24, 2003, and US Patent Application Serial 11/337 062, filed January 20, 2006, which is also incorporated into this description by reference.

Examples of special effects compositions that may be used include pigments and / or compositions that produce one or more appearance effects, such as reflection, pearlescent, metallic luster, phosphorescence, fluorescence, photochromicity, photosensitivity, thermochromism, goniochromism and / or variation colors. Additional special effects compositions may provide other tangible properties such as opacity or texture. According to the invention, special effects compositions can produce a color shift, so that the color of the coating changes when the coating is viewed from different angles. Examples of compositions with a color effect are identified in US patent No. 6894086, incorporated herein by reference. Additional color effect compositions may include transparent coated mica and / or synthetic mica, coated silica, coated alumina, clear liquid crystal pigment, liquid crystal coating and / or any composition where interference arises due to the difference in refractive index in the material rather than due to the difference in refractive index between the surface of the material and the air.

In accordance with the invention, a photosensitive composition and / or photochromic composition can be used that reversibly changes its color when exposed to one or more light sources. Photochromic and / or photosensitive compositions can be activated by exposure to radiation of a specific wavelength. When the composition is excited, the molecular structure changes, and the changed structure shows a new color that is different from the original color of the composition. When the exposure to radiation is removed, the photochromic and / or photosensitive composition may return to a state of rest in which the original color of the composition returns. According to the invention, the photochromic and / or photosensitive composition may be colorless in an unexcited state and may have color in an excited state. A complete color change can appear in the range from milliseconds to several minutes, for example, from 20 seconds to 60 seconds. Examples of photochromic and / or photosensitive compositions include photochromic dyes.

According to the invention, the photosensitive composition and / or photochromic composition can be coupled and / or at least partially linked, for example, by covalent bonding, to the polymeric and / or polymeric materials of the polymerized component. Unlike some coatings in which the photosensitive composition can migrate from the coating and crystallize in the substrate, the photosensitive composition and / or photochromic composition associated with and / or at least partially associated with the polymer and / or polymerizable component, in accordance with the invention, has minimal migration from coverage. Examples of photosensitive compositions and / or photochromic compositions and methods for their preparation are identified in US patent application No. 10 / 892,919, filed July 16, 2004, incorporated herein by reference.

In general, the colorant may be present in the coating composition in any amount sufficient to impart the desired visual and / or color effect. The dye may contain from 1 to 65 weight percent, for example, from 3 to 40 weight percent or from 5 to 35 weight percent, wherein the weight percent is based on the total weight of the composition.

In accordance with the present invention, it was unexpectedly and surprisingly found that applying an activating rinsing liquid described herein to a surface of a metal substrate before applying a metal phosphate pretreatment composition allows a solution (bath) containing a metal phosphate pretreatment composition (and therefore, the metallophosphate pretreatment composition used) is maintained at a lower temperature than methods using conventional activir guides liquid for washing, such as activators of the type Jernstedt or other activating fluid for washing the zinc phosphate containing metal phosphate particles having a D ₉₀ particle size greater than 10 microns. Since GW Jernstedt found the beneficial effects of activating metal surfaces by treating them with a solution containing titanium together with sodium phosphate before zinc phosphating, titanium-containing activating compositions are now commonly referred to as “Jernstedt type activators”. For example, in accordance with the present invention, a phosphate bath containing a metal phosphate pretreatment composition may be at a temperature not higher than 60 ° C, such as not more than 50 ° C, such as not more than 40 ° C, such as not higher than 30 ° C, for example, not higher than 25 ° C. According to the present invention, the temperature of the bath containing the metal phosphate pretreatment composition may be from 20 ° C to 60 ° C, for example, from 25 ° C to 50 ° C, for example from 30 ° C to 40 ° C. In accordance with the present invention, the use of an activating rinsing liquid described herein on the surface of a metal substrate before applying a metal phosphate pretreatment composition may allow a solution (bath) containing the metal phosphate pretreatment composition to be maintained at room temperature (20 ° C)

It was also unexpectedly and surprisingly found that applying the activating washing liquid described herein to the surface of a metal substrate before applying the metal phosphate pretreatment composition leads to the formation of a metal phosphate coating formed on the surface of the substrate, which has a lower coating weight, less phosphate crystal size, increased coating coverage and improved adhesion characteristics compared to metallophosphate coatings formed and on the substrate surfaces treated with conventional activating liquids for washing, such as Jernstedt type activators or activating liquids for washing containing metal phosphate particles having a D ₉₀ particle size greater than 10 microns. Not wishing to be bound by theory, it is believed that the smaller sizes of phosphate crystals are the result of a faster reaction of the activating liquid for washing with the surface of the substrate and more complete coverage of the surface of the substrate with nucleation sites, which leads to a more complete coverage of the surface of the substrate with the subsequent use of the composition for pretreatment, containing metal phosphate, even on an aluminum substrate.

As used herein, unless otherwise indicated, a plural term may encompass a single instance thereof, and vice versa, unless otherwise indicated. For example, although reference is made here to “a” metal sulfate salt and “a” dispersant, a combination (that is, a plurality) of these components can be used. In addition, in this application, the use of “or” means “and / or” unless specifically indicated otherwise, even if “and / or” can be explicitly used in certain cases.

As used here, the term “comprising”, “comprising” and similar terms is understood in the context of this application as a synonym for “including” and therefore is open and does not exclude the presence of additional undescribed or unaccounted for elements, materials, ingredients or process steps. As used herein, the term “consisting of” is understood in the context of this application to exclude the presence of any unspecified element, ingredient or method. As used herein, the term “consisting essentially of” is understood in the context of this application to include the indicated elements, materials, ingredients, solvents, or process steps, when applicable, while other materials not specified are inappropriate added to the composition and are present only as impurities in a combined amount of less than 5% by weight, based on the total weight of the composition.

As used herein, unless otherwise indicated, the term “substantially free” means that a particular material is not purposefully added to the activating rinse and is present only as an impurity in an amount of less than 1% by weight, based on the weight of the total weight of the activating liquid for washing. As used here, unless otherwise indicated, the term "completely free" means that the activating liquid for washing does not contain a specific material, that is, the activating liquid for washing contains 0% by weight of such material.

For the purposes of the following detailed description, it should be understood that the invention may take various alternatives and sequences of steps, unless explicitly stated otherwise. Moreover, except in any working examples or unless otherwise indicated, all numbers, such as those expressing values, sums, percentages, ranges, subranges and fractions, can be read as if preceded by the word “about”, even if this the term does not explicitly appear. Accordingly, unless otherwise indicated, the numerical parameters indicated in the following description and the attached claims are approximate, which may vary depending on the desired properties to be obtained in accordance with the present invention. Although the numerical ranges and parameters defining the wide scope of the invention are approximations, the numerical values indicated in the specific examples are communicated as accurately as possible. Any numerical value, however, inherently contains certain errors that inevitably arise as a result of the standard variation found in their respective test measurements. At least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of registered significant digits and the application of conventional rounding methods. In cases where a closed or open numerical range is described here, all numbers, values, quantities, percentages, subranges and fractions within or encompassed by the numerical range should be construed as specifically included in the initial disclosure of this application and belonging to its initial disclosure as if these numbers, values, quantities, percentages, subranges and fractions were clearly written out in full.

The invention is illustrated by the following examples, which should not be construed as limiting the invention to its details. All parts and percentages in the examples, as well as throughout the description, are by weight, unless otherwise indicated.

EXAMPLES

Flushing Activating Fluid Compositions

The following wash activating fluid compositions were prepared as follows:

RC: RC (a Jernstedt type activating washing liquid concentrate commercially available from PPG Industries, Inc., also known as VERSABOND® RC) was diluted in deionized (DI) water to a concentration of 1 g of a concentrate / l DI water to prepare a bath, containing the composition of the activating liquid for washing.

RC30, 1.1 g / l: 1.1 grams RC30 (zinc phosphate-based activating washing liquid concentrate with an average zinc phosphate particle size of about 1 μm and D ₉₀ 1-3 μm, commercially available from PPG Industries, Inc., also known as VERSABOND® 30) was added to 1 L of deionized water to obtain a zinc phosphate dispersion with a concentration of 1.1 g / L.

RC30, 3.3 g / L: 3.3 grams RC30 was added to 1 L of deionized water to obtain a zinc phosphate dispersion with a concentration of 3.3 g / L.

Composition 1A: The composition RC30 (1.1 g / l) was obtained as described above. To this composition was added 0.3 g / L zinc sulfate heptahydrate (available from Fisher Scientific and other chemical supply companies). Zinc sulfate heptahydrate was pre-dissolved in a minimum amount of DI water before being added to the RC30 composition. The resulting composition had a sulfate concentration of 100 ppm.

Composition 1B: The composition RC30 (1.1 g / l) was prepared as described above. To this composition was added 0.29 g / l of iron sulfate heptahydrate (available from Fisher Scientific and other chemical supply companies). Iron sulfate heptahydrate was pre-dissolved in a minimum amount of DI water before being added to the composition of RC30. The resulting composition had a sulfate concentration of 100 ppm.

Composition 1C: Composition RC30 (1.1 g / L) was prepared as described above. To this composition was added 0.27 g / L nickel sulfate hexahydrate (available from Fisher Scientific and other chemical supply companies). Nickel sulfate hexahydrate was previously dissolved in a minimum amount of DI water before being added to the composition of RC30. The resulting composition had a sulfate concentration of 100 ppm.

Composition 1D: Composition RC30 (1.1 g / L) was prepared as described above. To this composition was added 0.26 g / l of copper sulfate pentahydrate (available from Fisher Scientific and other chemical supply companies). Copper sulfate pentahydrate was previously dissolved in a minimum amount of DI water before being added to the RC30 bath. The resulting composition had a sulfate concentration of 100 ppm.

Composition 2A: Zinc phosphate ground with a microcarrier (MMM) is an activating liquid for washing based on zinc phosphate, which is obtained as follows: 1288.4 grams of zinc phosphate pigment was filtered into a pre-mixed mixture of 724 grams of deionized water, 787.7 grams of dispersing agent (Disperbyk-190, commercially available from BYK-Chemie GmbH) and 25.6 grams of antifoam (BYK-011, commercially available from BYK-Chemie GmbH) and mixed for 30 minutes using a Fawcett air mixer, model LS-103A with an angle from gmenta knife type 1 / Cowles blade mixer. This mixture was then ground in a recirculation mode through a horizontal mill with an Eiger Mini 250 abrasive (from EMIMills) containing 1.2-1.7 mm zirconium oxide support for 8.1 minutes of residence time. To 1695.7 grams of this pre-dispersion was added 150.3 grams of deionized water. This material was then pulverized in recirculation through the above-described Eiger mill, except that 0.3 mm zirconia support was used. The mixture was milled for an additional residence time of 40.1 minutes. During the grinding process, an additional 718 grams of deionized water was added, as well as 158.3 grams of Disperbyk-190 and 2 grams of Byk-011. During the grinding, several intermediate process samples were carried out, so that 1657.3 grams were obtained with a final yield. This material had a concentration of 27% by weight of zinc phosphate.

To obtain composition 2A, 1.85 grams of the above zinc phosphate dispersion was mixed with a liter of deionized water to obtain an activator bath with a zinc phosphate concentration of 0.5 g / L.

Composition 2B: a dispersion ground with a microcarrier (MMM) was obtained in the same manner as composition 2A. To obtain composition 2B, 5.55 grams of a zinc phosphate dispersion was mixed with a liter of deionized water to form an activator bath with a zinc phosphate concentration of 1.5 g / L.

Example 1

For each batch shown in Table 1, two cold-rolled steel panels (4 "x 6" available from ACT Test Panels, LLC) were spray cleaned with a mixture of Chemkleen 2010LP (1.25% v / v) / Chemkleen 181ALP ( 0.125% v / v) for 2 minutes at 49 ° C / 120 ° F, followed by washing by immersing in DI water for 15 seconds and washing by spraying with DI water for 15 seconds. The panels were then immersed in a bath (20 ° C-25 ° C) containing one of the activating washing liquids described above (RC, RC30, composition 1A or composition 2A, as shown in table 1) for 1 minute. The activated panels (RC, RC30, 1A or 2A) were then immersed in a zinc phosphate pretreatment bath (solution) (made from Chemfos 700, commercially available from PPG Industries, Inc., prepared in accordance with the supplier's instructions), at the bath temperature either 73F, 90F, 100F, or 125F (as indicated in table 1) for 2 minutes. Then, DI water was sprayed onto all panels for 20-30 seconds. The panels were dried with warm air using an Oster® portable Hi-Velocity dryer (model number 078302-300-000) with a high set point at a temperature of about 50-55 ° C until the panel became dry (about 1- 5 minutes).

For each batch, one of the panels was used to determine the completeness of phosphate coating. The other panel was cut in half to get two panels every 2 "x 3", and one of the half panels was used to determine the weight of the coating, and the other half of the panel was used to determine the average crystal size.

The zinc phosphate coating weight was determined on one of the 2 "x 3" panels by the weight-strip-weight method. Treated panels were weighed on an analytical balance to the nearest 0.1 mg. Cold rolled steel panels were immersed in a solution consisting of 100 g of granules of sodium hydroxide and 25 milliliters of 98% triethanolamine diluted to 1 liter of total volume with deionized water for 1.5 minutes to dissolve the entire zinc phosphate coating on the panels without dissolving the substrate. Hot-dip galvanized steel panels were immersed in a solution consisting of 16 g of ammonium dichromate [(NH ₄ ) ₂ Cr ₂ O ₇ ] dissolved in 1 liter of concentrated ammonium hydroxide for 2 minutes to dissolve the entire zinc phosphate coating on the panels without dissolving the substrate. After the stripping procedure, the panels were thoroughly washed with deionized water, carefully wiped with a cloth to remove any weakly adhering phosphate coating, washed again with deionized water and dried in warm air using an Oster® portable Hi-Velocity dryer (model number 078302-300-000) when setting a high set point at a temperature of about 50-55 ° C until the panel is dry, usually 1-5 minutes. Then, the dried panel was weighed, and weight loss was used to calculate the coating weight per unit area.

The average crystal size of zinc phosphate was determined on 2 "x 3" panels, first choosing a representative area of the panel, that is, a covered area of approximately 0.5 inches by 0.5 inches near the center of the 2 "x 3" panel without obvious coating defects, and then received image of either a 5000x or 10000x magnification using a Tescan Vega 2 scanning electron microscope (SEM). By magnification, the crystal size was determined with an increase of 10,000x required for smaller crystal sizes. Nine to twelve uniformly distributed crystals in each image were measured using ImageJ software (version 1.46), and the results were averaged. ImageJ Software is publicly available software available at http://imagej.nih.gov/ij/. More detailed information about the method is already described above.

The completeness of the coating (based on a quality scale that estimates% of the bare area), coating weight (g / ft ² ) and crystal size for the treated panels are shown in table 1 below.

TABLE 1

Activator Phosphate coverage Coating Weight (mg / ft²) The average crystal size (microns) RC (Jernstedt) 100% 266 3.4 RC30 (Dispersed Zinc Phosphate) 100% 232 1.8 Composition 1A 100% 131 1.3 Composition 2A 100% 176 1.3 RC (Jernstedt) 95% 265 4.1 RC30 (Dispersed Zinc Phosphate) 100% 209 2.3 Composition 1A 100% 132 1.0 Composition 2A 100% 153 1.2 RC (Jernstedt) fifty% 184 3.7 RC30 (Dispersed Zinc Phosphate) 100% 187 1.8 Composition 1A 100% 133 1.1 Composition 2A 100% 155 1.1 RC (Jernstedt) ~ 0% 40 Not RC30 (Dispersed Zinc Phosphate) 70% 169 2.2 Composition 1A 100% 108 0.9 Composition 2A 100% 142 1.2

The results show that the use of an activating rinse liquid, which includes either a metal sulfate salt or ground metal phosphate particles having a D _{90 of} less than 1 μm, leads to a decrease in the coating mass and crystal size of the subsequently phosphate coating compared to using a conventional activating liquid for a Jernstedt type wash or a wash activating liquid that does not include a metal sulfate salt. In addition, the inclusion of a metal sulfate salt or ground metal phosphate particles having a D _{90 of} less than 1 μm in an activating rinsing liquid allows the subsequent application of a full phosphate coating at low temperatures, for example 73 ° F, while activating rinsing liquids which do not include a metal sulfate salt or ground metal phosphate particles having a D _{90 of} less than 1 μm, do not have complete phosphate coatings at such low temperatures.

Example 2

For each batch shown in Table 2, cold rolled steel panels (4 "x 6" available from ACT Test Panels, LLC) were spray cleaned with a 2010 Chemkleen 2010LP (1.25% v / v) / Chemkleen 181ALP (0.125% v / v) ./vol.) for 2 minutes at 49 ° C / 120 F, followed by washing by immersing in DI water for 15 seconds and washing by spraying with DI water for 15 seconds. The panels were then immersed in a bath (20 ° C-25 ° C) containing one of the activating washing liquids described above (RC30 1.1 g / l, RC30 3.3 g / l, composition 2A, composition 2B, as shown in table 2) for 1 minute. The panels were then immersed in a zinc phosphate pretreatment bath (made from Chemfos 700 LT, commercially available from PPG Industries, Inc., prepared in accordance with the instructions provided by the supplier) (bath temperature 86 ° F) for 30, 60, 90 or 120 seconds (as shown in table 2). The panels were then washed by spraying DI water for 20-30 seconds. The panels were dried with warm air using an Oster® portable Hi-Velocity dryer (model number 078302-300-000) with a high setting point at a temperature of about 50-55 ° C until the panel was dry (about 1- 5 minutes).

For each batch, one of the panels was used to determine the completeness of phosphate coating. Another panel was cut in half to get two panels every 2 "x 3", and one of the half panels was used to determine the weight of the coating.

The completeness of the phosphate coating for the treated panels was evaluated as described in Example 1. The weight of the zinc phosphate atom coating on the treated panels was determined by the weight-band weighing method described in Example 1.

The completeness of the coating and the weight of the coating (g / m ² ) of the treated panels are shown in table 2 below.

TABLE 2

Activator Phosphate coverage Coating Weight (mg / ft²) Zinc phosphate treatment, time 30 seconds RC30, 1.1 g / l 25% 72 RC30, 3.3 g / l fifty% 86 Composition 2A 90% 83 Composition 2B 95% 85 Zinc phosphate treatment, time 60 seconds RC30, 1.1 g / l 60% 119 RC30, 3.3 g / l 90% 109 Composition 2A 100% 86 Composition 2B 100% 88 Zinc phosphate treatment, time 90 seconds RC30, 1.1 g / l 100% 176 RC30, 3.3 g / l 100% 130 Composition 2A 100% 118 Composition 2B 100% 104 Zinc phosphate treatment, 120 seconds RC30, 1.1 g / l 100% 187 RC30, 3.3 g / l 100% 122 Composition 2A 100% 119 Composition 2B 100% 83

One skilled in the art knows that it is not possible to coat zinc phosphate on a substrate when a bath containing the zinc phosphate pretreatment composition is maintained at 86 ° F using conventional Jernstedt salt activators, such as the RC composition described above. The results shown in Table 2 show that activation of the surface of the substrate with either composition 2A or composition 2B (i.e., zinc phosphate particles ground with microcarriers) resulted in a reduced immersion time in the pretreatment composition with zinc phosphate to achieve complete phosphate coating in comparison with activation by an activating washing liquid, which do not include zinc phosphate particles ground with microcarriers.

Example 3

For each batch shown in Table 3, two cold-rolled steel panels (4 "x 6" available from ACT Test Panels, LLC) and two aluminum panels (6022 alloy) (4 "x 6" available from ACT Test Panels, LLC ) were spray cleaned with a mixture of Chemkleen 2010LP (1.25% v / v) / Chemkleen 181ALP (0.125% v / v) for 2 minutes at 49 ° C / 120 ° F, followed by washing by immersion in DI water for 15 seconds and rinsing spraying DI water for 15 seconds. The panels were then immersed in a bath (20 ° C-25 ° C) containing either RC or one of the compositions 1A-1D described above for 1 minute. The panels were then immersed in a zinc phosphate pretreatment bath (manufactured from Chemfos 700 AL, commercially available from PPG Industries, Inc., prepared in accordance with the supplier's instructions) (bath temperature 86 ° F and 125 F) for 2 minutes (as shown in Table 2). The panels were then washed by spraying DI water for 20-30 seconds. The panels were dried with warm air using an Oster® portable Hi-Velocity dryer (model number 078302-300-000) with a high setting point at a temperature of about 50-55 ° C until the panel was dry (about 1- 5 minutes).

For each batch, one of the panels was used to determine the completeness of phosphate coating. The other panel was cut in half to get two panels every 2 "x 3", and one of the half panels was used to determine the weight of the coating, and the other half of the panel was used to determine the average crystal size.

The completeness of the zinc phosphate coating and the coating weight were determined by weighing the weight band described in Example 1.

The average crystal size of zinc phosphate was determined as described in example 1.

The completeness of the coating, coating weight (g / m ² ) and crystal size for the treated panels are shown in table 3 below.

TABLE 3

Activator Temperature Coldly-
rolled
steel Aluminum Phosphate coverage Weight coated
thia (mg / ft ² ) Crystal size
la (μm) Phosphate coverage Coating Weight (mgft²) Crystal Size (μm) RC30 (Dispersed Zinc Phosphate) 86 ° F 60% 153 3.4 80% 169 3.3 125 ° F 100% 203 2.2 100% 273 3.1 Composition 1A 86 ° F 100% 171 1.8 100% 132 2.7 125 ° F 100% 193 1.4 100% 172 1.8 Composition 1B 86 ° F 100% 153 1.0 100% 112 2.2 125 ° F 100% 210 1.2 100% 192 2.0 Composition 1C 86 ° F 100% 149 1.7 100% 149 1.9 125 ° F 100% 196 1.3 100% 168 1.1 Composition 1D 86 ° F 100% 165 1.5 80% 128 2.7 125 ° F 100% 220 1.5 100% 176 1.8

The results show that the use of an activating washing liquid, which includes a metal sulfate salt, leads to a decrease in the size of the phosphate crystals deposited after the phosphate coating compared to using an activating washing liquid, which does not include a metal sulfate. In addition, the use of an activating washing liquid, which includes a metal sulfate salt, usually improves the completeness of the phosphate coating after the phosphate coating is applied at a low temperature compared to using an activating washing liquid, which does not include a metal sulfate.

Example 4

For each batch shown in table 4, two cold-rolled steel panels were spray cleaned with a mixture of Chemkleen 2010LP (1.25% vol./about.) / Chemkleen 181ALP (0.125% vol./about.) For 2 minutes at 49 ° C / 120 F, followed by washing by immersing in DI water for 15 seconds and washing by spraying DI water for 15 seconds. The panels were then immersed in a bath (20 ° C-25 ° C) containing one of the activating washing liquids described above (RC30, composition 1A, composition 2A, which are shown in table 4) for 1 minute. The panels were then immersed in a zinc phosphate pretreatment bath (manufactured from Chemfos 700 AL, commercially available from PPG Industries, Inc., prepared in accordance with the supplier's instructions) (bath temperature 86 ° F and 125 F, as shown in Table 2) within 2 minutes. The panels were then washed by spraying DI water for 20-30 seconds. The panels were dried with warm air using an Oster® portable Hi-Velocity dryer (model number 078302-300-000) with a high setting point at a temperature of about 50-55 ° C until the panel was dry (about 1- 5 minutes).

Four panels were treated as described above and then plated by ED7000 made from materials supplied by PPG Industries, Inc. and used in accordance with the manufacturer's instructions. The two panels were then coated with a typical automotive overcoat in a topcoat system. Panels that were not coated with a topcoat were subjected to cyclic corrosion tests of GMW 14872 for 48 days. Topcoated panels were tested for corrosion by Volvo Florida Exposure for six months. The corrosion results are shown in table 4 below:

TABLE 4

Activator Phosphate temperature
zinc Coating Weight (mg / ft ² ) Crystal Size (μm) GMW 14872, average scribe creep (mm) Volvo Florida Exposure, Average Scribe Creep (mm) RC (Jernstedt) 125 ° F 234 3.2 7.2 12.7 Composition 1A 86 ° F 140 1.9 6.9 10.9 Composition 2A 86 ° F 106 1.3 5.8 10.1

Average Scribe Creep - average strain count

The results show that, although the coating mass and crystal size are much lower than the control, panels treated with an activating washing liquid, including a metal sulfate salt or ground metal phosphate particles having a D _{90 of} less than 1 μm at low temperature showed performance properties comparatively, if not better, in corrosion tests.

Example 5

Comparative example I was performed in accordance with example 2 of publication US 2012 / 0160129A1 by Inbe. RC and composition 2A were manufactured as described above.

The dispersion of Comparative I was characterized as follows and compared with the activation properties of composition 2A.

X-ray diffraction of the dried solids from comparative example I showed both ZnO and zinc phosphate.

Particle size (D ₁₀ , D ₅₀ and D ₉₀ ) was measured using a Mastersizer 2000 (available from Malvern Instruments, Ltd., Malvern, Worcestershire, UK). The laser beam (diameter 0.633 mm, wavelength 633 nm) was directed through a dispersion of particles (in deionized water up to 2-3% shading). The light scattering of the dispersion was measured (measurement parameters 25 ^° C., 2200 rpm, pre-measurement delay 30 seconds, background measurement 10 seconds, sample measurement 10 seconds), and the data were analyzed using software (Malvern Mastersizer 2000 software, version 5.60) for generating a particle size distribution from which the particle sizes were determined (average, D ₁₀ , D ₅₀ and D ₉₀ ) and are shown in Table 5.

TABLE 5

Sample Mean PS (μ) D10 (μ) D50 (μ) D90 (μ) Composition I (source) 3.914 1.528 3.495 6.904 Composition I (60 min) 0.643 0.125 0.456 1.31 Composition I (120 min) 0.493 0.109 0.338 0.985 Composition I (180 min) 0.474 0.096 0.284 0.917 Composition 2A 0.181 0.068 0.119 0.332 Composition RC30 0.846 0.079 0.215 2.75

For each batch shown in Table 6, cold-rolled steel, zinc-plated steel or 6022 aluminum alloy panels (4 "x 6", all available from ACT Test Panels, LLC) were spray cleaned with Chemkleen 2010LP (1.25% vol. ./vol.) / Chemkleen 181ALP (0.125% v / v) for 2 minutes at 49 ° C / 120 ° F, followed by washing by immersing in DI water for 15 seconds and washing by spraying with distilled water for 15 seconds. Then the panels were immersed in a bath (20 ° C-25 ° C) containing either comparative example I or composition 2A, as shown in table 5, for 1 minute. The activated panels (comparative example I or composition 2A) were then immersed in a zinc phosphate pretreatment bath (made from Chemfos 700AL, commercially available from PPG Industries, Inc., prepared in accordance with the supplier's instructions) at a bath temperature of 78F for 2 minutes . Then all panels were washed by spraying DI water for 20-30 seconds. The panels were dried with warm air using an Oster® portable Hi-Velocity dryer (model number 078302-300-000) with a high setting point at a temperature of about 50-55 ° C until the panel was dry (about 1- 5 minutes).

For each batch, one of the panels was used to determine the completeness of phosphate coating. The other panel was cut in half to get two panels every 2 "x 3", and one of the half panels was used to determine the weight of the coating, and the other half of the panel was used to determine the average crystal size.

The completeness of zinc phosphate coating and coating weight were determined as described in Example 1. The average crystal size of zinc phosphate was determined as described in Example 1. The data are shown in table 6 below.

TABLE 6

Substrate Activator Completeness of coverage Crystal Size (μm) Coating Weight (mg / ft ² ) Cold Rolled Steel (CRS) Composition 2A 100% 1.20 94 Cold rolled steel Comparative I 60% 2.88 153 Zinc Plated Steel (EG) Composition 2A 100% 1.22 289 Zinc Plated Steel Comparative I 100% 3.00 359 6022 aluminum alloy Composition 2A 95% 1.45 142 6022 aluminum alloy Comparative I 40% 3.05 153

As shown in table 5, composition 2A gave 100% coverage on CRS and 95% coverage on aluminum alloy panels 6022. In contrast, comparative I gave only 60% coverage on CRS and 40% coverage on panels made of aluminum alloy 6022. Both composition 2A and comparative I gave 100% coverage on steel EG panels, but a qualified person understands that EG panels usually cover 100%. Also, as shown in table 5, additionally, the crystal size was smaller and the coating weight was less on the panels treated with composition 2A than those treated with comparative I, regardless of the substrate.

Those skilled in the art will appreciate that numerous modifications and variations are possible in light of the foregoing disclosure without departing from the general concepts of the invention described and exemplified herein. Accordingly, it should be understood that the foregoing disclosure is merely an illustration of various exemplary aspects of this application, and that numerous modifications and variations can be easily made by those skilled in the art who are within the spirit and scope of this appendix and the appended claims.

Aspects of the invention:

1. Activating liquid for washing when processing the substrate, containing:

a dispersion of metal phosphate particles having a particle size of D _{90 of} not more than 10 μm, where the metal phosphate contains divalent or trivalent metals or combinations thereof;

dispersant; and

metal sulfate salt.

2. Activating washing liquid according to aspect 1, where the particle size D _{90 is} measured from a sample of activating washing liquid, which is subjected to ultrasound treatment.

3. An activating rinse liquid according to aspect 1 or 2, wherein the dispersant comprises a non-ionic dispersant.

4. The activating liquid for washing according to any one of the preceding aspects, in which the activating liquid for washing is essentially free of ionic dispersants.

5. An activating wash liquid according to any one of the preceding aspects, wherein the sulfate ion of a metal sulfate salt is present in an amount of 5 ppm to 5000 ppm based on the total weight of the activating wash liquid.

6. An activating wash liquid according to any one of the preceding aspects, wherein the metal of a metal sulfate salt is a divalent metal, wherein the divalent metal is preferably nickel, cobalt, zinc, iron, copper, or combinations thereof.

7. Activating rinse liquid according to any one of the preceding aspects, in which the metal phosphate particles have a particle size of D _{90 of} not more than 1 μm.

8. An activating rinse liquid according to any one of the preceding aspects, wherein the metal phosphate particles are substantially milled.

9. An activating rinse liquid according to any one of the preceding aspects, wherein the rinsing activating liquid comprises a multicomponent system, the dispersion of the metal phosphate particles and the dispersant being part of the first component and the metal sulfate salt being part of the second component.

10. Activating liquid for washing during processing of the substrate, containing:

a dispersion of substantially ground phosphate metal particles having a particle size of D _{90 of} not more than 1 μm, where the metal phosphate includes divalent or trivalent metals or combinations thereof; and

dispersant.

11. The activating washing liquid according to aspect 10, where the particle size D _{90 is} measured from a sample of the activating washing liquid, which has been subjected to ultrasonic treatment.

12. An activating wash liquid according to aspect 10 or 11, wherein the metal phosphate particles have a particle size D _{90 of} not more than 0.75 μm.

13. A method of processing a substrate, comprising contacting at least a portion of the surface of the substrate with an activating washing liquid according to any of the preceding aspects.

14. The method according to aspect 13, further comprising contacting at least a portion of the surface of the substrate that has been brought into contact with the activating rinse liquid with the metal phosphate pretreatment composition, wherein contacting the surface of the substrate with the phosphate pretreatment composition metal preferably includes immersing the substrate in a bath containing a composition for pre-treatment with metal phosphate, where the temperature of the bath is from 20 ° C to 60 ° C and preferably from 20 ° C to 25 ° C.

15. A substrate treated with an activating wash liquid according to any one of aspects 1-12, preferably in accordance with the method according to aspect 13 or 14.

16. The substrate according to aspect 15, further comprising a phosphate coating, in which the phosphate coating preferably contains phosphate crystals having a crystal size of from 0.4 μm to 4 μm, more preferably from 0.9 to 2.7 μm.

17. The substrate according to any one of aspects 15-16, wherein the substrate is hot dip galvanized steel.

Claims (18)

1. Activating liquid for washing in the processing of a metal substrate, containing: a dispersion of metal phosphate particles having a particle size of D _{90 of} not more than 10 μm, where the metal phosphate contains divalent or trivalent metals or combinations thereof; dispersant; and a metal sulfate salt that contains a metal in the form of: nickel, cobalt, zinc, iron, copper, or combinations thereof, moreover, the particle size D ₉₀ refers to the volume-weighted average particle size distribution in which 90% of the particles have a diameter smaller than D _90. 2. The activating liquid for washing according to claim 1, in which the dispersant contains a non-ionic dispersant. 3. The activating liquid for washing according to claim 1, in which the activating liquid for washing essentially does not contain ionic dispersants. 4. The activating liquid for washing according to claim 1, in which the sulfate ion salt of the metal sulfate is present in an amount of from 5 parts per million to 5000 parts per million, based on the total weight of the activating liquid for washing. 5. The activating liquid for washing according to any one of claims 1 to 4, in which the particles of metal phosphate have a particle size of D ₉₀ not more than 1 μm. 6. The activating liquid for washing according to any one of claims 1 to 5, in which the particles of metal phosphate are essentially crushed. 7. The activating liquid for washing according to any one of claims 1 to 6, in which the activating liquid for washing contains a multicomponent system, the dispersion of particles of metal phosphate and dispersant form part of the first component and the metal sulfate salt forms part of the second component. 8. The activating liquid for washing according to any one of claims 1 to 7, in which the particle size D _{90 is} measured from a sample of the activating liquid, which has been subjected to ultrasonic treatment. 9. A method of processing a metal substrate, comprising contacting at least a portion of the surface of the substrate with an activating liquid for washing according to any one of claims 1 to 8. 10. The method according to claim 9, further comprising contacting at least a portion of the surface of the substrate, which was brought into contact with an activating liquid for washing, with a composition for pretreatment with metal phosphate, wherein contacting the surface of the substrate with the metal phosphate pretreatment composition preferably comprises immersing the substrate in a bath containing the metal phosphate pretreatment composition, wherein the temperature of the bath is from 20 ° C. to 60 ° C., preferably from 20 ° C. to 25 ° C. . 11. A metal substrate treated with an activating washing liquid according to any one of claims 1 to 8. 12. The substrate of claim 11, further comprising a phosphate coating, which preferably includes phosphate crystals having a crystal size of from 0.4 μm to 4 μm, more preferably from 0.9 μm to 2.7 μm. 13. The substrate according to claim 11 or 12, which is a hot dip galvanized steel.