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US6020030A Expired / Lapsed US ⏱️ 0.0 years remaining

Coating an aluminum alloy substrate

Assignee: Alcoa Corp
•
Filing: 1998-05-07
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Granted: 2000-02-01
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Expires: 2018-05-07
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Abstract

Abstract An aluminum alloy substrate is pretreated with an aqueous solution containing an organophosphorus compound, preferably a vinyiphosphonic acid-acrylic acid copolymer, before coating the substrate with a polymer. Passing the substrate through the solution contaminates it with aluminum and other elements. The pretreatment solution is rejuvenated by removing aluminum with a cation exchange resin that preferably contains a styrene-divinyl benzene copolymer functionalized with sulfonate groups. Rinsing the substrate contaminates the rinse water with the copolymer. The rinse water is concentrated by reverse osmosis or membrane ultrafiltration and returned to the pretreatment solution.

Inventors

  • 👤 Joseph D. Guthrie
  • 👤 Alfred M. Dennis

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 23:13
CPC Classifications
B; B05; B05D; B05D7/00; B05D7/50; B05D7/52; B05D7/14; B05D7/16; C; C23; C23C; C23C22/00; C23C22/86

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 150 words
A process for coating an aluminum alloy substrate with a polymer, comprising: (a) providing an aluminum alloy substrate having a surface portion comprising aluminum oxide or aluminum hydroxide; (b) in a first container, pretreating said substrate with an aqueous pretreatment solution consisting essentially of water, an organophosphorus compound and metal ions, thereby to form a layer comprising a reaction product of said compound and said oxide or hydroxide, and wherein said substrate contaminates said solution with aluminum; (c) transferring at least a portion of said pretreatment solution to a second container containing a cation exchange resin, and therein adsorbing aluminum onto said resin and producing a treated solution containing a reduced concentration of aluminum; (d) returning said treated solution from said second container to said first container; and (e) coating said layer with a coating composition comprising a polymer selected from the group consisting of polyvinyl chloride, epoxies and polyesters.
Claim 2
Dependent Claim 150 words
A process for coating an aluminum alloy substrate with a polymer, comprising: (a) providing an aluminum alloy substrate having a surface portion comprising aluminum oxide or aluminum hydroxide; (b) in a first container, pretreating said substrate with an aqueous pretreatment solution consisting essentially of water, an organophosphorus compound and metal ions, thereby to form a layer comprising a reaction product of said compound and said oxide or hydroxide, and wherein said substrate contaminates said solution with aluminum; (c) transferring at least a portion of said pretreatment solution to a second container containing a cation exchange resin, and therein adsorbing aluminum onto said resin and producing a treated solution containing a reduced concentration of aluminum; (d) returning said treated solution from said second container to said first container; and (e) coating said layer with a coating composition comprising a polymer selected from the group consisting of polyvinyl chloride, epoxies and polyesters.
Claim 3
Dependent Claim 37 words
The process of claim 1 further comprising: (f) after step (b), rinsing said substrate with water, thereby to produce rinse water containing said organophosphorus compound and aluminum; and (g) concentrating said rinse water by removing water therefrom.
Claim 4
Dependent Claim 25 words
The process of claim 2 further comprising: (h) returning to the first container at least a portion of the rinse water treated in step (g).
Claim 5
Dependent Claim 15 words
The process of claim 1 wherein said organophosphorus compound comprises a vinylphosphonic acid-acrylic acid copolymer.
Claim 6
Dependent Claim 15 words
The process of claim 4 wherein said copolymer comprises about 5-50 mole percent vinylphosphonic acid.
Claim 7
Dependent Claim 17 words
The process of claim 4 wherein said copolymer has a molecular weight of about 20,000 to 100,000.
Claim 8
Dependent Claim 16 words
The process of claim 4 wherein said pretreatment solution comprises about 1-20 g/L of said copolymer.
Claim 9
Dependent Claim 21 words
The process of claim 4 wherein said pretreatment solution has a temperature of about 120-200° F. (49-93° C.) in step (b).
Claim 10
Dependent Claim 13 words
The process of claim 1 wherein said resin comprises a styrene-divinyl benzene copolymer.
Claim 11
Dependent Claim 13 words
The process of claim 1 wherein said resin is functionalized with sulfonate groups.
Claim 12
Dependent Claim 15 words
The process of claim 1, wherein step (b) is performed without anodically oxidizing said substrate.
Claim 13
Dependent Claim 16 words
The process of claim 1, wherein the treated solution contains less than about 75 ppm aluminum.
Claim 14
Dependent Claim 16 words
The process of claim 1, wherein the treated solution contains less than about 25 ppm aluminum.
Claim 15
Dependent Claim 141 words
A process for pretreating an aluminum alloy sheet having a surface portion in order to improve adhesion of a polymer coating to said surface portion, comprising: (a) in a first container, pretreating an aluminum alloy sheet having a surface portion comprising aluminum oxide or aluminum hydroxide with a solution consisting essentially of water, an organophosphorus compound, and metal ions, thereby forming a layer comprising a reaction product of said compound and said oxide or hydroxide, and contaminating said solution with aluminum ions; (b) transferring at least a portion of said solution to a second container containing a cation exchange resin comprising a polymer functionalized with sulfonate groups and therein adsorbing aluminum ions onto said resin, thereby producing a treated solution containing said compound and having a reduced concentration of aluminum ions; and (c) returning said treated solution to said first container.
Claim 16
Dependent Claim 141 words
A process for pretreating an aluminum alloy sheet having a surface portion in order to improve adhesion of a polymer coating to said surface portion, comprising: (a) in a first container, pretreating an aluminum alloy sheet having a surface portion comprising aluminum oxide or aluminum hydroxide with a solution consisting essentially of water, an organophosphorus compound, and metal ions, thereby forming a layer comprising a reaction product of said compound and said oxide or hydroxide, and contaminating said solution with aluminum ions; (b) transferring at least a portion of said solution to a second container containing a cation exchange resin comprising a polymer functionalized with sulfonate groups and therein adsorbing aluminum ions onto said resin, thereby producing a treated solution containing said compound and having a reduced concentration of aluminum ions; and (c) returning said treated solution to said first container.
Claim 17
Dependent Claim 29 words
The process of claim 14 further comprising: (d) coating said layer with a coating composition comprising a polymer selected from the group consisting of polyvinyl chloride, epoxies and polyesters.
Claim 18
Dependent Claim 12 words
The process of claim 14 wherein said resin comprises a styrene-divinylbenzene copolymer.
Claim 19
Dependent Claim 22 words
The process of claim 14 wherein said sheet comprises an aluminum alloy of the AA 2000, 3000, 5000, 6000 or 7000 series.
Claim 20
Dependent Claim 17 words
The process of claim 14 wherein said sheet comprises an aluminum alloy of the AA 5000 series.
Claim 21
Dependent Claim 15 words
The process of claim 14 wherein step (a) is performed without anodically oxidizing said substrate.
Claim 22
Dependent Claim 17 words
The process of claim 14 wherein the treated solution contains less th an about 75 ppm aluminum.
Claim 23
Dependent Claim 16 words
The process of claim 14, wherein the treated solution contains less than about 25 ppm aluminum.
Claim 24
Dependent Claim 141 words
A process for treating an aluminum alloy sheet having a surface portion in order to improve adhesion of a polymer coating to said surface portion, comprising: (a) in a first container, pretreating an aluminum alloy sheet having a surface portion comprising aluminum oxide or aluminum hydroxide with a solution consisting essentially of water and a vinyl phosphonic acid-acrylic acid copolymer without anodically oxidizing said surface portion, thereby forming a layer comprising a reaction product of said copolymer and said oxide or hydroxide, and contaminating said solution with aluminum ions; (b) transferring at least a portion of said solution to a second container containing a cation exchange resin and therein adsorbing aluminum ions onto said resin, thereby producing a treated solution containing said copolymer and having a reduced concentration of aluminum ions; and (c) returning said treated solution to said first container.
Claim 25
Dependent Claim 141 words
A process for treating an aluminum alloy sheet having a surface portion in order to improve adhesion of a polymer coating to said surface portion, comprising: (a) in a first container, pretreating an aluminum alloy sheet having a surface portion comprising aluminum oxide or aluminum hydroxide with a solution consisting essentially of water and a vinyl phosphonic acid-acrylic acid copolymer without anodically oxidizing said surface portion, thereby forming a layer comprising a reaction product of said copolymer and said oxide or hydroxide, and contaminating said solution with aluminum ions; (b) transferring at least a portion of said solution to a second container containing a cation exchange resin and therein adsorbing aluminum ions onto said resin, thereby producing a treated solution containing said copolymer and having a reduced concentration of aluminum ions; and (c) returning said treated solution to said first container.

References Cited (Backward Citations)

US3276868A Cited
US4153461A Cited
US4206049A Cited
US4747954A Cited
US4861490A Cited
US5103550A Cited
US5277788A Cited
US5368974A Cited
US5534238A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2003-01-31 2003-08-02 2004-02-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-01-31 2007-08-02 2008-02-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-01-31 2011-08-02 2012-02-01 $7700.00 Window Closed / Lapsed

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