← Back to Patent Explorer
US4497876A Expired / Lapsed US ⏱️ 0.0 years remaining

Corrosion resistant metal composite with zinc and chromium coating

Assignee: Diamond Shamrock Corp
•
Filing: 1983-03-16
•
Granted: 1985-02-05
•
Expires: 2003-03-16
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A metal composite is provided extended corrosion resistance. Prior to joining the metals of the composite, at least one of the metals is provided with a metallic undercoat. This undercoat is then coated with a metallic zinc layer. Lastly, a heat curable and substantially resin free topcoat is established on the zinc layer and cured. The topcoat composition contains chromium in non-elemental form and may further contain particulate metal, all in liquid medium. The metal composite is then formed by contacting metals including the thus coated metal. In addition to outstanding corrosion resistance, the composite can retain substrate weldability while further enhancing weatherability.

Inventors

  • 👤 William E. Kidon

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 05:52
CPC Classifications
C; C23; C23C; C23C22/00; C23C22/73; C23C22/74; C25; C25D; C25D5/00; C25D5/10; C25D5/12; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/12028; Y10T428/12063; Y10T428/1209; Y10T428/12493; Y10T428/12535; Y10T428/12556; Y10T428/12611; Y10T428/12771; Y10T428/12785; Y10T428/12792; Y10T428/25; Y10T428/256

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 126 words
A corrosion-resistant coated metal substrate having a coating including a metallic laminate protective composite containing adjacent layers of dissimilar metals, with said coating composite comprising: (a) a metallic undercoating layer of a metal dissimilar from the metal of said substrate and free from other metals except in trace amounts; (b) a metallic zinc layer on said undercoating layer and dissimilar from said undercoating metal; and, (c) a heat-curable, substantially resin free topcoat layer from composition curable to a water resistant protective coating, said topcoat layer containing from about 20 to about 500 milligrams per square foot of chromium, as chromium, in non-elemental form, and with there being more than about 20 weight percent of said chromium as hexavalent chromium, said composition containing hexavalent-chromium-providing-substance in liquid medium.
Claim 2
Dependent Claim 126 words
A corrosion-resistant coated metal substrate having a coating including a metallic laminate protective composite containing adjacent layers of dissimilar metals, with said coating composite comprising: (a) a metallic undercoating layer of a metal dissimilar from the metal of said substrate and free from other metals except in trace amounts; (b) a metallic zinc layer on said undercoating layer and dissimilar from said undercoating metal; and, (c) a heat-curable, substantially resin free topcoat layer from composition curable to a water resistant protective coating, said topcoat layer containing from about 20 to about 500 milligrams per square foot of chromium, as chromium, in non-elemental form, and with there being more than about 20 weight percent of said chromium as hexavalent chromium, said composition containing hexavalent-chromium-providing-substance in liquid medium.
Claim 3
Dependent Claim 35 words
The coated metal substrate of claim 1 wherein said metal substrate is ferrous metal, and said ferrous metal is coated with a metallic undercoating selected from the group consisting of nickel, cobalt, tin and copper.
Claim 4
Dependent Claim 18 words
The coated metal substrate of claim 2 wherein said metallic undercoating is up to about one micron thick.
Claim 5
Dependent Claim 28 words
The coated metal substrate of claim 1 wherein said substrate metal is selected from the group consisting of ferrous metal and zinc-, nickel-, cadmium-, cobalt-, and chromium-containing alloys.
Claim 6
Dependent Claim 21 words
The coated metal substrate of claim 1 further characterized by having up to about 25 microns thickness of metallic undercoating layer.
Claim 7
Dependent Claim 21 words
The coated metal substrate of claim 5 wherein said metallic undercoating layer is from about 0.2 to about 10 microns thick.
Claim 8
Dependent Claim 48 words
The coated metal substrate of claim 1 further characterized by having a cured, water resistant topcoat layer containing more than about 20 weight percent, but less than about 50 weight percent, of said chromium in hexavalent form and said topcoat layer is applied as aqueous-based heat-curable, coating composition.
Claim 9
Dependent Claim 16 words
The coated metal substrate of claim 1 wherein said water resistant topcoat layer contains particulate metal.
Claim 10
Dependent Claim 28 words
The coated metal substrate of claim 8 wherein said particulate metal is selected from the group consisting of zinc, aluminum, manganese, magnesium, mixtures thereof and alloys of same.
Claim 11
Dependent Claim 35 words
The coated metal substrate of claim 8 further characterized by having said water resistant topcoat layer containing said particulate metal in an amount above about 50 milligrams per square foot of coated metallic zinc layer.
Claim 12
Dependent Claim 56 words
The coated metal substrate of claim 8 further characterized by having said water resistant topcoat layer containing up to about 5,000 milligrams per square foot of coated metallic zinc layer of said pulverulent metal and said topcoat layer further has a weight ratio of chromium, as chromium, to pulverulent metal of not substantially above about 0.5:1.
Claim 13
Dependent Claim 22 words
The coated metal substrate of claim 1 wherein said water resistant and substantially free resin free topcoat layer is further phosphate free.
Claim 14
Dependent Claim 22 words
The coated metal substrate of claim 1 wherein said topcoat layer contains at least one of said laminate metals in particulate form.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-02-05 1988-08-06 1989-02-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-02-05 1992-08-06 1993-02-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-02-05 1996-08-06 1997-02-05 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag