阅读说明：本技术 金属衬底处理方法以及包括膦酸酯官能化层的制品 (Metal substrate treatment method and article comprising phosphonate functionalized layer ) 是由 R·N·斯科特 K·M·罗巴里 J·L·吉奥肯迪 N·梅内加佐 K·M·韦勒 于 2019-12-18 设计创作，主要内容包括：提供了金属衬底处理方法以及包括膦酸酯官能化层的制品。所述方法包括使包括铝和铝合金中的至少一种的金属衬底与流体接触,以在所述金属衬底的至少一个区上形成膦酸酯官能化层。所述流体包括含膦酸酯的酸和其衍生物中的至少一种。所述含膦酸酯的酸和所述其衍生物中的至少一种包括第一酸性质子的pKa。所述流体的pH比所述第一酸性质子的所述pKa大至少0.5pH值。所述制品包括金属衬底和膦酸酯官能化层,所述金属衬底包括铝或铝合金且所述膦酸酯官能化层在所述金属衬底的至少一个区上。(Metal substrate processing methods and articles including phosphonate functionalized layers are provided. The method includes contacting a metal substrate comprising at least one of aluminum and an aluminum alloy with a fluid to form a phosphonate functionalization layer on at least one region of the metal substrate. The fluid includes at least one of a phosphonate containing acid and derivatives thereof. At least one of the phosphonate containing acid and the derivative thereof comprises a pKa of the first acidic proton. The pH of the fluid is at least 0.5pH greater than the pKa of the first acidic proton. The article includes a metal substrate comprising aluminum or an aluminum alloy and a phosphonate functionalized layer on at least one region of the metal substrate.)

1. A metal substrate processing method, comprising:

contacting a metal substrate comprising at least one of aluminum and an aluminum alloy with a fluid comprising at least one of a phosphonate containing acid and derivatives thereof to form a phosphonate functionalized layer on at least one region of the metal substrate,

wherein the at least one of the phosphonate containing acid and the derivative thereof comprises a pKa of a first acidic proton, and wherein the pH of the fluid is at least 0.5pH greater than the pKa of the first acidic proton.

2. The method of claim 1, wherein the pH of the fluid is at least 2pH values greater than the pKa of the first acidic proton.

3. The method of any one of claims 1-2, wherein the fluid comprises a pH in the range of 3.5 to 9.5.

4. The method of any one of claims 1 to 3, wherein the phosphonate containing acid is at least one of: phosphorous acid, phenylphosphonic acid, ethylphosphonic acid, octylphosphonic acid, octadecylphosphonic acid, vinylphosphonic acid, dimethyl vinylphosphonate, diethylenetriamine pentamethylenephosphonic acid, octane diphosphonic acid and derivatives of each of these compounds.

5. The method of any one of claims 1 to 4, wherein the at least one of the phosphonate containing acid and the derivative thereof has the formula

Wherein R is₁、R₂And R₃Independently selected from hydrogen, alkyl and aryl.

6. The method of any one of claims 1 to 5, wherein the fluid comprises from 0.1 weight percent to 20 weight percent of the at least one of the phosphonate containing acid and derivatives thereof, based on the total weight of the fluid.

7. The method of any of claims 1 to 6, wherein contacting the metal substrate comprises at least one of: immersing the metal substrate in a bath of the fluid, spraying the fluid onto the metal substrate, and wiping the fluid onto the metal substrate.

8. The method of claim 7, wherein contacting the metal substrate comprises immersing the metal substrate in a bath of the fluid, and further comprising agitating the bath of fluid using at least one method selected from the group consisting of: bubbling a gas through the fluid in the bath, and agitating the fluid in the bath.

9. The method of any one of claims 1 to 8, wherein the fluid contacts the metal substrate for a time in the range of 1 second to 40 minutes.

10. The method of any one of claims 1 to 9, wherein the phosphonate functional layer comprises phosphonate groups bonded to the metal substrate.

11. The method of any one of claims 1 to 10, wherein the CIELAB brightness difference (Δ L) between the metal substrate including the phosphonate functionalized layer and the metal substrate without the phosphonate functionalized layer is no more than 10 as measured with a bick-gardner color meter 45/0 spectrophotometer.

12. The method of any of claims 1-11, further comprising, prior to contacting the metal substrate:

cleaning the metal substrate, wherein cleaning comprises at least one of alkaline cleaning, acid cleaning, and carbon dioxide based cleaning techniques.

13. The method of any of claims 1-12, further comprising depositing a coating over at least a portion of the phosphonate functionalized layer on the metal substrate.

14. The method of claim 13, wherein the coating comprises at least one of a siloxane, a silazane, a fluoropolymer, an acrylic, an epoxy, a polyester, and a polyurethane.

15. An article of manufacture, comprising:

a metal substrate comprising aluminum or an aluminum alloy; and

a phosphonate functionalization layer on at least one region of the metal substrate.

16. The article of claim 15, wherein the phosphonate functional layer comprises phosphonate groups bonded to the metal substrate.

17. The article of any one of claims 15 to 16, further comprising a coating deposited over at least one region of the phosphonate functionalized layer.

18. The article of claim 17, wherein the coating comprises at least one of a siloxane, a silazane, a fluoropolymer, an acrylic, an epoxy, a polyester, and a polyurethane.

19. The article of any one of claims 16 to 18, wherein the article is configured as at least one of an aerospace component, an automotive component, a transportation component, and a building and construction component.

20. The article of any one of claims 16 to 19, wherein the article is a vehicle wheel.

Technical Field

The present disclosure relates to metal substrate processing methods and articles including phosphonate functionalized layers.

Background

Various surface treatments can be applied to the metal substrate. The surface treatment may impart different properties to the surface of the metal substrate. Designing a durable and aesthetically desirable surface treatment presents challenges.

Disclosure of Invention

In one aspect, a metal substrate processing method is provided. The method includes contacting a metal substrate comprising at least one of aluminum and an aluminum alloy with a fluid to form a phosphonate functionalization layer on at least one region of the metal substrate. The fluid includes at least one of a phosphonate containing acid and derivatives thereof. The at least one of the phosphonate containing acid and the derivative thereof comprises a pKa of the first acidic proton. The pH of the fluid is at least 0.5pH greater than the pKa of the first acidic proton.

In another aspect, an article is provided. The article includes a metal substrate comprising aluminum or an aluminum alloy and a phosphonate functionalized layer on at least one region of the metal substrate.

It is to be understood that the invention disclosed and described in this specification is not limited to the aspects outlined in this summary. The reader will appreciate the foregoing details, as well as others, upon considering the following detailed description in terms of various non-limiting and non-exhaustive aspects of the specification.

Drawings

The features and advantages of the examples, and the manner of attaining them, will become more apparent and the examples will be better understood by reference to the following description taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a flow chart illustrating a non-limiting embodiment of a metal substrate coating process according to the present disclosure;

FIG. 2 is a schematic illustration of a non-limiting embodiment of an article according to the present disclosure, the article including a metal substrate and a phosphonate functionalization layer on at least one region of the metal substrate;

FIG. 3 provides images showing portions of samples A-D after thermal shock exposure;

FIG. 4A is a modified image showing samples N and O after the CASS test; and is

Fig. 4B is a modified image of fig. 4A selectively showing the etching pits formed on the samples N and O.

Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate certain embodiments in one form, and such exemplifications are not to be construed as limiting the scope of the appended claims in any manner.

Detailed Description

Various examples are described and illustrated herein to provide a general understanding of the structure, function, and use of the disclosed articles and methods. The various examples described and illustrated herein are non-limiting and non-exhaustive. Accordingly, the invention is not limited by the description of the various non-limiting and non-exhaustive examples disclosed herein. Rather, the invention is limited only by the claims. The features and characteristics shown and/or described in connection with the various examples may be combined with the features and characteristics of other examples. Such modifications and variations are intended to be included within the scope of this description. Thus, the claims may be amended to recite any features or features explicitly or inherently described in this specification, or otherwise explicitly or inherently supported. In addition, the applicant reserves the right to amend the claims to expressly deny features or characteristics that may exist in the prior art. The various embodiments disclosed and described in this specification can include, consist of, or consist essentially of the various described features and characteristics herein.

Any reference herein to "various embodiments," "some embodiments," "one embodiment," "an embodiment," or similar phrases, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases "in various embodiments," "in some embodiments," "in one embodiment," "in an embodiment," or similar phrases in the specification do not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics described may be combined in any suitable manner in one or more embodiments. Thus, a particular feature, structure, or characteristic shown or described in connection with one embodiment may be combined, in whole or in part, with a feature, structure, or characteristic of one or more other embodiments without limitation. Such modifications and variations are intended to be included within the scope of the present embodiments.

In the present specification, unless otherwise indicated, all numerical parameters should be understood as being preceded and modified in all instances by the term "about" where the numerical parameter has the inherent variability characteristic of the underlying measurement technique used to determine the value of the parameter. At the very 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 reported significant digits and by applying ordinary rounding techniques.

Also, any numerical range recited herein includes all sub-ranges subsumed within that range. For example, a range of "1 to 10" includes all subranges between (and including) the minimum value of 1 and the maximum value of 10, i.e., a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10. Any maximum numerical limitation recited in this specification is intended to include all lower numerical limitations subsumed therein, and any minimum numerical limitation recited in this specification is intended to include all higher numerical limitations subsumed therein. Accordingly, applicants reserve the right to modify the specification (including the claims) to specifically recite any sub-ranges subsumed within the ranges explicitly recited herein. All such ranges are inherently described in this specification.

As used herein, the grammatical articles "a", "an" and "the" are intended to include "at least one" or "one or more" even if the term "at least one" or "one or more" is explicitly used in some instances, unless otherwise indicated. Thus, the foregoing grammatical articles are used herein to refer to one or more (i.e., to "at least one") of the particular identified elements. Furthermore, unless the context requires otherwise, the use of a singular noun includes the plural, and the use of a plural noun includes the singular.

As used herein, the term "phosphonate" refers to a phosphorus compound comprising one phosphorus atom coordinated to three oxygen atoms. One of the three oxygen atoms may be coordinated to the phosphorus atom through a double bond. Phosphonates not including phosphoric acid (H)₃O₄P). For example, the phosphonate may comprise general formula (I), wherein R₁、R₂And R₃Independently selected from hydrogen, alkyl or aryl. Thus, R₁、R₂And R₃May be the same or different groups.

Formula (I)

Selecting a surface treatment may require, for example, a balance between desired adhesion, corrosion protection, and aesthetic properties. In accordance with the present disclosure, a metal substrate treatment method is provided that can promote adhesion of a top coat layer to a metal substrate, provide corrosion protection properties to the metal substrate, and provide a desired aesthetic appearance of the metal substrate. Additionally, the present disclosure provides articles comprising a phosphonate functionalized layer. Articles comprising the phosphate functionalized layer thereon may exhibit topcoat to article adhesion, including improved corrosion resistance, improved abrasion resistance, and/or have a desirable aesthetic appearance.

A metal substrate processing method according to the present disclosure includes contacting a metal substrate with a fluid including a composition that can form a phosphonate functionalized layer on at least one region of the metal substrate. Contacting the metal substrate may comprise at least one of: the method includes immersing the metal substrate in a bath of fluid, spraying the fluid onto the metal substrate, and wiping the metal substrate with the fluid. In certain embodiments in which contacting the metal substrate includes immersing the metal substrate in a bath of fluid, the bath of fluid may be agitated. For example, the fluid bath may be agitated by at least one method selected from the group consisting of: bubbling a gas through the fluid in the bath, and agitating the fluid (e.g., circulating the fluid through a pump, agitating the fluid through an impeller).

In various embodiments of the method, the fluid may contact the metal substrate for at least 1 second, such as at least 5 seconds, at least 10 seconds, at least 30 seconds, at least 1 minute, at least 5 minutes, at least 10 minutes, at least 20 minutes, or at least 30 minutes. The fluid may contact the metal substrate for no more than 40 minutes, such as no more than 30 minutes, no more than 20 minutes, no more than 10 minutes, no more than 5 minutes, no more than 1 minute, no more than 30 seconds, no more than 10 seconds, or no more than 5 seconds. In certain embodiments of the method, the fluid may contact the metal substrate for a time in the range of 1 second to 40 minutes, such as 2 seconds to 10 minutes, 5 seconds to 5 minutes, 5 seconds to 2 minutes, or 10 seconds to 30 seconds. The fluid may react with the metal substrate during the contact time.

The fluid may include at least one of a phosphonate containing acid and derivatives thereof. For example, in certain embodiments, the phosphonate containing acid can be at least one of: phosphorous acid (H)₃O₃P), phenylphosphonic acid (C)₆H₇O₃P), ethylphosphonic acid (C)₂H₇O₃P), octyl phosphonic acid (C)₈H₁₉O₃P), octadecylphosphonic acid (C)₁₈H₃₉O₃P), vinylphosphonic acid (C)₂H₅O₃P), dimethyl vinylphosphonate (C)₄H₁₀O₃P), diethylenetriamine penta (methylene phosphonic acid) (CH)₅O₃P), octane diphosphonic acid (C)₈H₂₀O₆P₂) And derivatives of any of these compounds. The derivative of phosphonic acid can be, for example, a deprotonated phosphonic acid (e.g., a deprotonated derivative, conjugate base thereof) and/or an at least twice protonated phosphonic acid. For example, the derivative of phosphonic acid may include at least one of: deprotonated phosphorous acid (H)₂O₃P^-) Deprotonated phenylphosphonic acid (C)₆H₆O₃P^-) Deprotonated ethylphosphonic acid (C)₂H₆O₃P^-) Deprotonated octylphosphonic acid (C)₈H₁₈O₃P^-) Deprotonated octadecylphosphonic acid (C)₁₈H₃₈O₃P^-) Deprotonated vinylphosphonic acid (C)₂H₄O₃P^-) Deprotonated dimethyl vinylphosphonate (C)₄H₉O₃P^-) Deprotonated diethylenetriamine penta (methylene phosphonic acid) (CH)₅O₃P^-) And deprotonated octane diphosphonic acid (C)₈H₁₉O₆P₂ ^-)。

The phosphonate-containing acid and/or derivative thereof can include the pKa of the first acidic proton (e.g., -log of the acid dissociation constant)₁₀Ka). The pKa of the first acidic proton corresponds toThe pH of the phosphonate containing acid and its corresponding conjugate base (e.g., deprotonated phosphonate containing acid) are present in the solution at substantially equal concentrations. Increasing the pH of the solution comprising the phosphonate containing acid and/or derivative thereof above the pKa of the first acidic proton can increase the concentration of the conjugate base and decrease the concentration of the phosphonate containing acid. Lowering the pH of the solution comprising the phosphonate containing acid and/or derivative thereof below the pKa of the first acidic proton can decrease the concentration of the conjugate base and increase the concentration of the phosphonate containing acid. The conjugate base may include a negative charge (-1). The phosphonate containing acid may include a neutral charge.

In various embodiments, the phosphonate containing acid and/or derivative thereof can include at least two pKa's, such as a pKa of the first acidic proton and a pKa of the second acidic proton. The pKa of the second acidic proton corresponds to the pH at which substantially equal concentrations of the conjugate base and the corresponding secondary conjugate base (e.g., twice the deprotonated conjugate base) are present in solution. The secondary conjugate base may comprise two negative charges (-2). In various examples, the phosphonate containing acid and/or derivative thereof can include at least three pKa. In various embodiments in which the phosphonate containing acid and/or derivative thereof comprises phosphorous acid, the pKa of the first acidic proton may be 1.3 and the pKa of the second acidic proton may be 6.7. In various embodiments in which the phosphonate containing acid and/or derivative thereof comprises ethylphosphonic acid, the pKa of the first acidic proton may be 2.4 and the pKa of the second acidic proton may be 8.1. In various embodiments in which the phosphonate containing acid and/or derivative thereof comprises phenylphosphonic acid, the pKa of the first acidic proton may be 1.8 and the pKa of the second acidic proton may be 7.1. In various embodiments in which the phosphonate containing acid and/or derivative thereof comprises vinylphosphonic acid, the pKa of the first acidic proton may be 2.6 and the pKa of the second acidic proton may be 7.3.

The pH of the fluid used in the present method may be selected based on the desired reactivity of the phosphonate containing acid and/or derivative thereof. The pH of the fluid may be selected to reduce the solubility of the metal substrate in the fluid, thereby extending the life of the fluid. In various embodiments, the pH of the fluid may be at least 0.5pH greater than the pKa of the first acidic proton, e.g., at least 1pH greater, at least 2pH greater, at least 3pH greater, at least 4pH greater, at least 5pH greater, at least 6pH greater, or at least 8pH greater than the pKa of the first acidic proton. In certain embodiments, the pH of the fluid may be no more than 10pH values greater than the pKa of the first acidic proton, for example no more than 8pH values greater than the pKa of the first acidic proton, no more than 6pH values greater than the pKa of the first acidic proton, no more than 5pH values greater than the pKa of the first acidic proton, no more than 4pH values greater than the pKa of the first acidic proton, no more than 3pH values greater than the pKa of the first acidic proton, no more than 2pH values greater than the pKa of the first acidic proton, no more than 1pH value greater than the pKa of the first acidic proton, or no more than 0.5pH values greater than the pKa of the first acidic proton. In certain embodiments according to the present disclosure, the pH of the fluid may be in a range from the pKa of the first acidic proton to a pH value greater than 10pH value of the pKa of the first acidic proton, for example, in a range from at least 0.5pH value greater than the pKa of the first acidic proton to a pH value greater than 8pH value of the pKa of the first acidic proton, or in a range from at least 4pH value greater than the pKa of the first acidic proton to a pH value greater than 6pH value of the first acidic proton. In some embodiments, the fluid may comprise a pH in the range of the pKa of the first acidic proton to the pKa of the second acidic proton. In various embodiments, the fluid comprises a pH wherein the phosphonate containing acid substantially dissociates into a conjugate base.

In certain embodiments, the pH of the fluid may be greater than 1, such as greater than 1.5, greater than 2, greater than 2.5, greater than 3, greater than 4, greater than 5, greater than 5.5, greater than 6, greater than 6.5, greater than 7, greater than 8, greater than 8.5, greater than 9, or greater than 10. For example, the pH of the fluid may be no more than 12, such as no more than 11, no more than 10, no more than 9, no more than 8.5, no more than 8, no more than 7, no more than 6.5, no more than 6, no more than 5.5, no more than 5, no more than 4, no more than 3, no more than 2.5, or no more than 2. In various embodiments, the pH of the fluid may be in the range of 1 to 12, such as 1.5 to 10, 1.5 to 9, 2.5 to 8, 4 to 10, 6 to 10, 4 to 8, 6 to 8, 5.5 to 8.5, or 6.5 to 8.5.

In certain embodiments, the fluid used in the present methods may be an aqueous liquid solution. For example, the fluid may include a phosphonate containing acid and/or derivative thereof having an equilibrium of water and optionally buffers, stabilizers, surfactants, and/or other additives.

In some embodiments, the fluid may comprise at least 0.1 weight percent phosphonate containing acid and/or derivative thereof based on the total weight of the fluid, for example at least 0.5 weight percent, at least 1 weight percent, at least 2 weight percent, at least 5 weight percent, at least 10 weight percent, or at least 15 weight percent phosphonate containing acid and/or derivative thereof based on the total weight of the fluid. In various embodiments, the fluid includes no more than 20 weight percent phosphonate containing acid and/or derivative thereof based on the total weight of the fluid, such as no more than 15 weight percent, no more than 10 weight percent, no more than 5 weight percent, no more than 2 weight percent, no more than 1 weight percent, or no more than 0.5 weight percent phosphonate containing acid and/or derivative thereof based on the total weight of the fluid. In certain embodiments, the fluid comprises from 0.1 to 20 weight percent phosphonate containing acid and/or derivative thereof based on the total weight of the fluid, for example from 0.2 to 10 weight percent, from 0.5 to 10 weight percent, from 0.2 to 5 weight percent, or from 0.5 to 2 weight percent phosphonate containing acid and/or derivative thereof based on the total weight of the fluid.

Contacting the metal substrate with a fluid can form a phosphonate functionalization layer on the metal substrate. For example, an oxide present on the surface of the metal substrate (e.g., aluminum oxide when the substrate comprises aluminum or an aluminum alloy) can be modified by a phosphonate containing acid within the fluid and form a phosphonate functionalized layer on at least one region of the metal substrate. The phosphonate functionalized layer can include phosphonate groups bonded to the metal substrate. In various embodiments, the phosphonate group is bonded to the metal substrate through a P-O-Al bond. In various embodiments, the phosphonate group can be bonded to an oxide group on the metal substrate or directly to a metal atom. The phosphonate functionalized layer can improve the corrosion performance of the metal substrate and can improve the adhesion of the coating to the metal substrate.

In various embodiments, the phosphonate functionalized layer does not affect, or only minimally affects, the aesthetics of the metal substrate. For example, the difference in color space brightness (Δ L) between a metal substrate without a phosphonate functionalization layer (e.g., prior to contact with a fluid) and a metal substrate comprising a phosphonate functionalization layer thereon (e.g., after contact with a fluid) can be minimized. In various embodiments, the CIELAB brightness difference (Δ L) between the metal substrate including the phosphonate functionalization layer and the metal substrate without the phosphonate functionalization layer is no more than 10, e.g., no more than 8, no more than 5, no more than 3, no more than 2, no more than 1, or no more than 0.5, as measured with a BYK-Gardner Spectro Guide 45/0Spectrophotometer 45/0 Spectrophotometer. In certain embodiments, the CIELAB brightness difference (Δ L) between the metal substrate including the phosphonate functionalized layer and the metal substrate without the phosphonate functionalized layer is greater than 0.1, greater than 0.5, or greater than 1 as measured with a bick-gardner color meter 45/0 spectrophotometer. In some embodiments, the CIELAB brightness difference (Δ L) between the metal substrate including the phosphonate-functionalized layer and the metal substrate without the phosphonate-functionalized layer is 0. In certain embodiments, the CIELAB brightness difference (Δ L) between the metal substrate including the phosphonate functionalized layer and the metal substrate without the phosphonate functionalized layer is in the range of 0 to 10, e.g., 0 to 5, 0 to 3, 0 to 2, 0 to 1, or 0.1 to 2, as measured with a bick-gardner colorimeter 45/0 spectrophotometer.

In certain embodiments herein, a metal substrate processing method according to the present disclosure may be incorporated into a metal substrate coating process, as schematically illustrated in fig. 1, for example. The metal substrate coating process may include cleaning the metal substrate 102. For example, in certain embodiments, the metal substrate can be cleaned by at least one of a caustic wash, an acid wash, and a carbon dioxide based cleaning technique. In various embodiments, the metal substrate may be rinsed to remove residual chemicals used during the cleaning 104. Rinsing may include, for example, spraying the metal substrate with a solution including water. In various embodiments, the metal substrate may be polished prior to cleaning the metal substrate.

The metal substrate processing method according to the present disclosure may be performed on a metal substrate. For example, the metal substrate may be contacted with a fluid having a composition that can form a phosphonate functionalized layer on at least one region of the metal substrate 106. The cleaning step 104 may occur before the contacting step 106. The metal substrate may be rinsed to remove residual fluid 108. Rinsing may include, for example, spraying the metal substrate with water or a solution including water. In various embodiments, the metal substrate may be dried.

In the embodiment shown in fig. 1, the coating composition can be deposited over a phosphonate functionalization layer on the metal substrate 110. The coating composition can be deposited by, for example, at least one of spray coating, spin coating, dip coating, roll coating, flow coating, and film coating. The coating composition can be deposited in contact with the phosphonate functional layer.

As used herein, particularly in connection with coatings or films, the terms "on … …," "to … …," "over … …," and variations thereof (e.g., "coated over … …," "formed over … …," "deposited over … …," "disposed over … …," "positioned over … …," etc.) mean coated, formed, deposited, disposed, or otherwise positioned over, but not necessarily in contact with, a surface of a substrate. For example, a coating "coated over" a substrate does not preclude the presence of one or more other coatings of the same or different compositions disposed between the coated coating and the substrate. Likewise, for example, a second coating "coated over" a first coating does not preclude the presence of one or more other coatings of the same or different composition positioned between the applied second coating and the applied first coating.

After depositing the coating composition, the coating composition may be cured to form the coating 112 on the metal substrate. As used herein, the term "cure" refers to chemical crosslinking of components in the curable composition and/or the chain extension of the curable composition. Thus, the term "curing" does not merely encompass physical drying of the curable composition by solvent or vehicle evaporation. In this regard, the term "curing" as used in this specification refers to the conditions of the curable composition in which the components of the curable composition have chemically reacted to form new covalent bonds.

For example, curing the coating composition may include at least one of ambient curing, gas flow, ultraviolet radiation, electron beam radiation, gamma radiation, heat, and oxygen. In various embodiments, curing the coating composition may include flashing off the solvent in the coating composition.

In various embodiments, the coating comprises at least one of a siloxane, a silazane, a fluoropolymer, an acrylic, an epoxy, a polyester, and a polyurethane. The coating may be substantially transparent, or the coating may be opaque. As used herein, the term "substantially transparent" refers to a coating that produces no or little scattering or diffuse reflection of visible electromagnetic radiation. In certain embodiments, the coating may be colorless. In various embodiments, the coating may comprise a colorant, such as a pigment or dye. In various embodiments, the coating may protect the article from, for example, wear and/or corrosion.

Fig. 2 shows an article 200 comprising a metal substrate 202 and a phosphonate functionalization layer 204 on at least one region of the metal substrate 202. The phosphonate functionalization layer 204 can be in contact with and bonded to the metal substrate 202. A coating 206 may be deposited over at least one region of the phosphonate functionalization layer 204. The phosphonate functionalization layer 204 can be bonded to the coating 206 and can be in contact with the coating 206. The phosphonate functionalization layer 204 can promote adhesion between the coating 206 and the metal substrate 202.

In certain embodiments, the metal substrate and the article comprising the substrate may comprise at least one of aluminum and an aluminum alloy. For example, the aluminum alloy may include at least one of a 1000 series aluminum alloy, a 2000 series aluminum alloy, a 3000 series aluminum alloy, a 4000 series aluminum alloy, a 5000 series aluminum alloy, a 6000 series aluminum alloy, and a 7000 series aluminum alloy. In various examples, the aluminum alloy can include 6061 aluminum alloy and/or 6361 aluminum alloy. In various embodiments, the aluminum alloy can include a 5000 series aluminum alloy with added zinc. In various embodiments, the aluminum alloy may include a356 and/or a 357. The article comprising the metal substrate comprising the phosphonate functionalized layer can be an article used in various product applications, such as industrial applications, consumer applications (e.g., consumer electronics devices and/or equipment), or commercial end uses in other fields. For example, an article comprising a metal substrate comprising a phosphonate functionalized layer can be used in at least one of the aerospace field (e.g., aerospace component), the automotive field (e.g., automotive component), the transportation field (e.g., transportation component), or the construction and construction field (e.g., construction component or construction component). In certain embodiments, an article comprising a metal substrate comprising a phosphonate functionalized layer can be configured as at least one of an aerospace component, an automotive component, a transportation component, and a building and construction component.

In various embodiments, articles comprising a metal substrate comprising a phosphonate functionalized layer can be used in high temperature applications, such as in the aerospace or automotive fields. In certain embodiments, an article comprising a metal substrate comprising a phosphonate functionalization layer can be used as an engine component in an aerospace vehicle (e.g., in the form of a blade, such as a compressor blade incorporated into an engine). In other embodiments, articles comprising a metal substrate comprising a phosphonate functionalization layer can be used as a heat exchanger component in an engine of an aerospace vehicle. The aerospace vehicle containing the engine assembly/heat exchanger may then be operated. In certain embodiments, the article comprising the metal substrate comprising the phosphonate functionalized layer may be an automotive engine component. A vehicle incorporating such an automotive component (e.g., an engine component) may then be operated. For example, an article comprising a metal substrate comprising a phosphonate functionalization layer can be used as a turbocharger component (e.g., a compressor wheel of a turbocharger where high temperatures can be generated by recirculating engine exhaust gas returned through the turbocharger) and an automotive vehicle comprising the turbocharger component can be operated. In another embodiment, an article comprising a metal substrate comprising a phosphonate functionalization layer can be used as a blade in a land-based (stationary) turbine that generates electricity, and the land-based turbine comprising a metal portion can be operated to generate electricity. In certain embodiments, articles comprising a metal substrate comprising a phosphonate functionalization layer can be used in a repellency application, such as in human armor or an armored vehicle (e.g., armored steel sheet). In other embodiments, articles comprising a metal substrate comprising a phosphonate functionalization layer can be used in consumer electronics applications, such as in laptop computer housings, battery cases, cell phones, cameras, mobile music players, handheld devices, computers, televisions, microwave ovens, kitchen ware, washing/drying machines, refrigerators, or sporting goods.

In certain embodiments, articles comprising a metal substrate comprising a phosphonate functionalized layer can be used in structural applications, such as aerospace structural applications or automotive structural applications. For example, articles comprising a metal substrate comprising a phosphonate functionalized layer can be formed into various aerospace structural components, including, for example, floor beams, seat rails, fuselage frames, bulkheads, spars, ribs, stringers, and brackets. In various embodiments, articles comprising a metal substrate comprising a phosphonate functionalized layer can be used in automotive structural applications. For example, articles comprising a metal substrate comprising a phosphonate functionalized layer may be formed into various automotive structural components, including nodes such as space frames, vibration damping supports, and sub-frames. In one embodiment, the article comprising the metal substrate comprising the phosphonate functionalized layer can be a body-in-white automotive product.

In another aspect, articles comprising a metal substrate comprising a phosphonate functionalized layer can be used in industrial engineering. For example, articles comprising a metal substrate comprising a phosphonate functionalized layer can be formed into various industrial engineering products, such as pallets, tool boxes, bolt plates, bridge plates, and ramps.

In various embodiments, the metal substrate may be, or may be part of, a wheel. The wheel may be at least one of a bond wheel, a weld wheel, a (e.g., vacuum formed) formed wheel, a cured wheel, a cast wheel, a forged wheel, and an additive manufactured wheel. The wheel may have been subjected to further processing, such as machining or polishing, to provide a finished wheel.

Examples of the invention

Samples a-S of a metal substrate comprising a 6000 series aluminum alloy were prepared and polished. Samples a-S are contacted with a phosphorous acid solution (e.g., a fluid comprising a phosphonate containing acid and/or derivatives thereof) to produce a phosphonate functionalized layer thereon. The phosphorous acid solution comprises phosphorous acid in the range of 0.5 to 2 weight percent (98% ultrapure powder available from zeimer femtole technologies, waltham, massachusetts) with the remainder being water.

Samples a and B were exposed to 0.6 weight percent phosphorous acid solution at pH 1.5 for 1 minute and 3 minutes, respectively. Samples C and D were exposed to a 0.6 wt% solution at pH 6.5 for 1 minute and 3 minutes, respectively. Thereafter, samples A-D were coated with a silicone coating and tested for adhesion. Adhesion performance was tested by: the coating is scribed in an "X" shape by the blade through to the metal substrate to expose the underlying metal substrate. The adhesion of the coating to the metal substrate was evaluated by thermal shock according to GM 9525P, allowing the samples to undergo a single water soak/freeze/thaw (steam exposure) cycle. After thermal shock exposure, a portion of each sample a-D containing an "X" shaped scribe is shown in fig. 3. Sample a showed a large loss of adhesion as evidenced by loss of coating around the center of the "X" shaped scribe line on sample a, and sample B showed a loss of adhesion as evidenced by the chip in the coating near the upper right segment of the "X" scribe line on sample B. No loss of adhesion was observed for samples C and D. Thus, the coating adhesion was improved for samples C and D compared to examples a and B. It is believed that other metal substrate pretreatment methods according to the present disclosure may also achieve improved adhesion performance.

Samples E-M were contacted with either a solution comprising 0.5 weight percent phosphorous acid or a 2 weight percent phosphorous acid solution. Thereafter, samples E-M were coated with a silicone coating. Sample E-M was tested for corrosion resistance against filamentous track formation (filiform track formation). The wire trace formation test was performed by scribing a 1.5 inch long line through the coating with a razor blade to expose the underlying metal substrate. Samples E-M were then exposed to a copper accelerated acetate spray (fog) test (CASS test) according to ASTM B368-09 (2014). After the CASS test, the longest filamentous locus length (e.g., silk-like corrosion from streaks) of each of samples E-M was measured with a ruler under a microscope. The test of the corrosion performance of each sample E-M was repeated two more times, for a total of 3 measurements for each sample E-M. Table 1 shows the average of the longest filamentous locus lengths of 3 measurements for each of samples E-M.

Table 1:

sample G exhibited improved filiform corrosion performance (average filiform trace length 25% less) compared to sample E. Sample H exhibited improved filiform corrosion performance (average filiform trace length 38% less) compared to sample F. Sample I exhibited improved filiform corrosion performance (average filiform trace length 51% less) compared to sample E. Sample L showed improved filiform corrosion performance (average filiform trace length 21% less) compared to sample J. Sample M exhibited improved filiform corrosion performance (average filiform trace length 25% less) compared to sample K. It is believed that other metal substrate pretreatment methods according to the present disclosure may also achieve improved filiform corrosion performance.

The sizes of samples N and O are substantially equal. Samples N and O were prepared in duplicate. Sample N was contacted with 0.6 weight percent phosphorous acid solution at pH 1.5 and sample O was contacted with 0.6 weight percent phosphorous acid solution at pH 6.5. After coating samples N and O with the silicone coating, samples N and O were subjected to CASS testing according to ASTM B368-09 (2014).

Regional corrosion (corrosion away from the scribe lines) on samples N and O after the CASS test was measured by image analysis. To perform image analysis, an image of each of samples N and O is captured and modified according to similar parameters to emphasize the pitting on each sample. Fig. 4A shows the image. The image shown in fig. 4A is then further modified to selectively enhance regional erosion, and these further modified images are shown in fig. 4B. Regional corrosion on each of the samples shown in FIG. 4B was measured by counting pits on the sample and by measuring the total surface area occupied by all pits on the sample. Sample N had an average of 63 pits and an average total pit surface area of 205mm². Sample O had an average of 19 pits, which was a 70% improvement (based on the number of pits) over sample N. Sample O had an average total etch pit surface area of 35.5mm²An improvement of 83% compared to sample N. It is believed that other metal substrate pretreatment methods according to the present disclosure may also achieve improved corrosion of the area.

In the polished state, the L value of each of the samples P-S was measured with a bick-gardner colorimeter 45/0 spectrophotometer. These L values are referred to herein as L₁. The samples P-S were then alkali washed and the L value (L x) of each sample was measured spectrophotometrically with a bick-gardner colorimeter 45/0 after alkali washing₂)。

Samples P-Q were contacted with 0.6 weight percent phosphorous acid solution. Samples P and R were contacted with a solution of pH 1.5, while samples Q and S were contacted with a phosphorous acid solution of pH 6.5. Samples P and Q were contacted with their respective phosphorous acid solutions for 1 minute, and samples R and S were contacted with their respective phosphorous acid solutions for 3 minutes. After contacting the samples P-S with the phosphorous acid solution, the L value (L x) of each of the samples P-S was measured with a bick-gardner colorimeter 45/0spectrophotometer₃). After coating each of samples P-S with the silicone coating, the L value (L x) of each sample P-S was measured spectrophotometrically with a bick-gardner color meter 45/0₄)。

Several measured L values for samples P-S are provided in table 2. Table 2 also lists the values Δ L ═ L ·₃-L*₁L, and the value Δ L ″ ═ L |₄-L*₁|。

TABLE 2

The measured Δ L 'values for sample Q were increased over the Δ L' values for sample P. Specifically, the Δ L' value of sample Q was 99% less than sample P. The measured Δ L' values for sample S were increased over those for sample R. Specifically, the Δ L' value of sample S was 99% less than that of sample R. It is believed that other metal substrate pretreatment methods according to the present disclosure may also achieve an increase Δ L' and/or Δ L ".

Aspects of the invention

Various aspects of the invention include, but are not limited to, the aspects set forth in the following numbered clauses.

1. A metal substrate processing method, comprising: contacting a metal substrate comprising at least one of aluminum and an aluminum alloy with a fluid comprising at least one of a phosphonate containing acid and derivatives thereof, wherein the at least one of the phosphonate containing acid and the derivatives thereof comprises a pKa of a first acidic proton, and wherein the pH of the fluid is at least 0.5pH greater than the pKa of the first acidic proton, to form a phosphonate functionalized layer on at least one region of the metal substrate.

2. The method of clause 1, wherein the pH of the fluid is at least 2pH values greater than the pKa of the first acidic proton.

3. The method of any of clauses 1-2, wherein the fluid comprises a pH of 11 or less.

4. The method of any of clauses 1-3, wherein the fluid comprises a pH in the range of 3.5 to 9.5.

5. The method of any of clauses 1-4, wherein the fluid comprises a pH in the range of 6.5 to 8.5.

6. The method of any of clauses 1-5, wherein the phosphonate containing acid is at least one of: phosphorous acid, phenylphosphonic acid, ethylphosphonic acid, octylphosphonic acid, octadecylphosphonic acid, vinylphosphonic acid, dimethyl vinylphosphonate, diethylenetriamine pentamethylenephosphonic acid, octane diphosphonic acid and derivatives of each of these compounds.

7. The method of any of clauses 1-6, wherein the at least one of the phosphonate containing acid and the derivative thereof has the formula

Wherein R is₁、R₂And R₃Independently selected from hydrogen, alkyl or aryl.

8. The method of any of clauses 1-7, wherein the fluid comprises from 0.1 to 20 weight percent of the at least one of the phosphonate containing acid and derivatives thereof, based on the total weight of the fluid.

9. The method of any of clauses 1-8, wherein the fluid comprises from 0.2 to 5 weight percent of the at least one of the phosphonate containing acid and derivatives thereof, based on the total weight of the fluid.

10. The method of any of clauses 1-9, wherein the fluid comprises from 0.5 to 2 weight percent of the at least one of the phosphonate containing acid and derivatives thereof, based on the total weight of the fluid.

11. The method of any of clauses 1-10, wherein contacting the metal substrate comprises at least one of: immersing the metal substrate in a bath of the fluid, spraying the fluid onto the metal substrate, and wiping the fluid onto the metal substrate.

12. The method of clause 11, wherein contacting the metal substrate comprises immersing the metal substrate in a bath of the fluid, and further comprising agitating the bath of fluid by at least one method selected from the group consisting of: bubbling a gas through the fluid in the bath, and agitating the fluid in the bath.

13. The method of any of clauses 1-12, wherein the fluid contacts the metal substrate for a time in the range of 1 second to 40 minutes.

14. The method of any of clauses 1-13, wherein the fluid contacts the substrate for a time in the range of 5 seconds to 5 minutes.

15. The method of any of clauses 1-14, wherein the fluid contacts the substrate for a time in the range of 10 seconds to 30 seconds.

16. The method of any of clauses 1-15, wherein the phosphonate functional layer comprises phosphonate groups bonded to the metal substrate.

17. The method of any of clauses 1-16, wherein the CIELAB brightness difference (Δ L) between the metal substrate including the phosphonate functionalized layer and the metal substrate without the phosphonate functionalized layer is no more than 10 as measured with a bick-gardner color meter 45/0 spectrophotometer.

18. The method of any of clauses 1-17, further comprising, prior to contacting the metal substrate:

cleaning the metal substrate, wherein cleaning comprises at least one of alkaline cleaning, acid cleaning, and carbon dioxide based cleaning techniques.

19. The method of any of clauses 1-18, further comprising depositing a coating over at least a portion of the phosphonate functionalized layer on the metal substrate.

20. The method of clause 19, wherein the coating comprises at least one of a siloxane, a silazane, a fluoropolymer, an acrylic, an epoxy, a polyester, and a polyurethane.

21. The method of any of clauses 1-20, wherein the article comprising the metal substrate is configured as at least one of an aerospace component, an automotive component, a transportation component, and a building and construction component.

22. The method of clause 21, wherein the article comprising the metal substrate is a vehicle wheel.

23. An article of manufacture, comprising:

a metal substrate comprising aluminum or an aluminum alloy; and

a phosphonate functionalization layer on at least one region of the metal substrate.

24. The article of clause 23, wherein the phosphonate functionalized layer comprises a phosphonate group bonded to the metal substrate.

25. The article of any of clauses 23 to 24, further comprising a coating deposited over at least one region of the phosphonate functionalized layer.

26. The article of clause 25, wherein the coating comprises at least one of a siloxane, a silazane, a fluoropolymer, an acrylic, an epoxy, a polyester, and a polyurethane.

27. The article of any of clauses 23-26, wherein the article is configured as at least one of an aerospace component, an automotive component, a transportation component, and a building and construction component.

28. The article of any of clauses 23-26, wherein the article is a vehicle wheel.

Those skilled in the art will recognize that the articles and methods described herein, and the discussion accompanying them, are used as examples for the sake of conceptual clarity, and that various configuration modifications are contemplated. Thus, as used herein, the specific examples/embodiments set forth and the accompanying discussion are intended to be representative of their more general categories. Generally, any specific examples are used to indicate their class, and no particular component, device, operation/act, or object is to be considered limiting. While the present disclosure provides a description of various specific aspects for the purpose of illustrating various aspects of the disclosure and/or its potential applications, it is to be understood that variations and modifications will occur to those skilled in the art. Accordingly, the invention(s) described herein should be understood to be at least as broad as desired, rather than being more narrowly defined than the specific illustrative aspects provided herein.