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US4414350A Expired / Lapsed US ⏱️ 0.0 years remaining

Ferrous complexing agent for autodeposition

Assignee: Henkel Corp
•
Filing: 1981-08-24
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Granted: 1983-11-08
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Expires: 2001-08-24
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Abstract

Abstract An autodepositing coating composition of the ferric iron-containing type wherein ferrous iron tends to build up in concentration in the composition and affect adversely the coating capabilities of the composition as it is used continuously to autodeposit coatings on iron-containing surfaces, the improvement comprising adding to said composition, in an amount effective to decrease the amount of ferrous iron which tends to adversely affect the coating capabilities of the composition, a carboxylic acid which is effective in forming a complex with said ferrous iron.

Inventors

  • 👤 Wilbur S. Hall

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 10:53
CPC Classifications
B; B05; B05D; B05D7/00; B05D7/14; B05D7/142

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 151 words
An acidic aqueous autodepositing coating composition of the ferric iron-containing type wherein ferrous iron tends to build up in concentration in the aqueous phase of the composition and affect adversely the coating capabilities of the composition as it is used continuously to form an autodeposited coating on ferrous surfaces, said composition comprising an organic coating-forming material, dissolved ferric iron and hydrofluoric acid, and including also dissolved ferrous iron and, in an amount effective to maintain the coating capabilities of the composition, a carboxylic acid which is soluble in the composition and which is effective in forming a complex with said ferrous iron in the composition, said carboxylic acid having a dissociation constant of about 1.5×10 -5 to about 1×10 -3 and being selected from the group consisting of succinic, citric, itaconic, malic, lactic, tartaric, fumaric, glacial acrylic, gallic and acetic acid and a mixture of two or more of said acids.
Claim 2
Dependent Claim 151 words
An acidic aqueous autodepositing coating composition of the ferric iron-containing type wherein ferrous iron tends to build up in concentration in the aqueous phase of the composition and affect adversely the coating capabilities of the composition as it is used continuously to form an autodeposited coating on ferrous surfaces, said composition comprising an organic coating-forming material, dissolved ferric iron and hydrofluoric acid, and including also dissolved ferrous iron and, in an amount effective to maintain the coating capabilities of the composition, a carboxylic acid which is soluble in the composition and which is effective in forming a complex with said ferrous iron in the composition, said carboxylic acid having a dissociation constant of about 1.5×10 -5 to about 1×10 -3 and being selected from the group consisting of succinic, citric, itaconic, malic, lactic, tartaric, fumaric, glacial acrylic, gallic and acetic acid and a mixture of two or more of said acids.
Claim 3
Dependent Claim 13 words
A composition according to claim 1 wherein said carboxylic acid is citric acid.
Claim 4
Dependent Claim 24 words
A composition according to claim 1, or 2 wherein said carboxylic acid is present in an amount of about 0.5 to about 10 g/l.
Claim 5
Dependent Claim 27 words
A composition according to claim 3 wherein said coating-forming material comprises dispersed solid resin particles and wherein ferric fluoride is a source of said dissolved ferric iron.
Claim 6
Dependent Claim 9 words
A composition according to claim 4 including also pigment.
Claim 7
Dependent Claim 124 words
An acidic aqueous autodepositing coating composition of the ferric iron-containing type wherein ferrous iron tends to build up in concentration in the aqueous phase of the composition and affect adversely the coating capability of the composition as it is used continuously to form an autodeposited coating on ferrous surfaces, said composition comprising dispersed solid resin particles, ferric fluoride, and hydrofluoric acid, and including also dissolved ferrous iron and about 0.5 to about 10 g/l of a carboxylic acid having a dissociation constant of about 1.5×10 -5 to about 1×10 -3 , said carboxylic acid being selected from the group consisting of succinic, citric, itaconic, malic, lactic, tartaric, fumaric, glacial acrylic, gallic and acetic acid and a mixture of two or more of said acids.
Claim 8
Dependent Claim 124 words
An acidic aqueous autodepositing coating composition of the ferric iron-containing type wherein ferrous iron tends to build up in concentration in the aqueous phase of the composition and affect adversely the coating capability of the composition as it is used continuously to form an autodeposited coating on ferrous surfaces, said composition comprising dispersed solid resin particles, ferric fluoride, and hydrofluoric acid, and including also dissolved ferrous iron and about 0.5 to about 10 g/l of a carboxylic acid having a dissociation constant of about 1.5×10 -5 to about 1×10 -3 , said carboxylic acid being selected from the group consisting of succinic, citric, itaconic, malic, lactic, tartaric, fumaric, glacial acrylic, gallic and acetic acid and a mixture of two or more of said acids.
Claim 9
Dependent Claim 13 words
A composition according to claim 6 wherein said carboxylic acid is citric acid.

References Cited (Backward Citations)

US3791431A Cited
US3914519A Cited
ZA721146B Cited
US3865617A Cited
US4214022A Cited
US4215162A Cited
US4186219A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-11-07 1987-05-09 1987-11-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-11-07 1991-05-09 1991-11-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-11-07 1995-05-09 1995-11-08 $7700.00 Window Closed / Lapsed

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