Patent US2893198A successfully refreshed from Google Patents.
Patent US4660467A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4450050A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for bonding high efficiency chromium electrodeposits

Assignee: M&T Chemicals Inc
•
Filing: 1983-02-03
•
Granted: 1984-05-22
•
Expires: 2003-02-03
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An adherent chromium deposit is obtained on a substrate by means of a process which involves applying an adherent iron containing deposit to the substrate, anodic treating the iron containing deposit and depositing chromium on the treated, iron containing deposit from a bath containing a halogen releasing compound selected from the group consisting of iodine releasing compounds, bromine releasing compounds and mixtures thereof. Supplemental catalysts such as sulfates, simple and complex fluorides, borates, carboxylates, chlorides, chlorates and perchlorates can also be present. The process can further include the step of activating the substrate in an acid bath or an iron or an iron alloy plating bath prior to iron plating from an iron salt containing bath.

Inventors

  • 👤 Hyman Chessin
  • 👤 Edmund C. Knill

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 04:00
CPC Classifications
C; C25; C25D; C25D5/00; C25D5/10; C25D5/12; C25D3/00; C25D3/02; C25D3/04; C25D5/34; C25D5/627

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 111 words
A method of consistently forming an adherent chromium deposit on a metal substrate comprising the steps of: (a) plating the substrate metal with iron or an iron alloy from an iron salt containing bath for a time and at a current density sufficient to produce an adherent iron or iron alloy plating on the substrate metal; (b) depositing chromium on the iron or iron alloy plated metal substrate from a chromic acid bath containing a halogen releasing compound selected from the group consisting of iodine releasing compounds, bromine releasing compounds and mixtures thereof and chromic acid for a time and at a current density sufficient to produce an aherent chromium plating.
Claim 2
Independent Claim 111 words
A method of consistently forming an adherent chromium deposit on a metal substrate comprising the steps of: (a) plating the substrate metal with iron or an iron alloy from an iron salt containing bath for a time and at a current density sufficient to produce an adherent iron or iron alloy plating on the substrate metal; (b) depositing chromium on the iron or iron alloy plated metal substrate from a chromic acid bath containing a halogen releasing compound selected from the group consisting of iodine releasing compounds, bromine releasing compounds and mixtures thereof and chromic acid for a time and at a current density sufficient to produce an aherent chromium plating.
Claim 3
Dependent Claim 41 words
The method of claim 1, further comprising the step of subjecting the iron containing deposit on the substrate metal to an anodic treatment in a chromic acid containing bath prior to the step of depositing chromium on the plated metal substrate.
Claim 4
Dependent Claim 34 words
The method of claim 1 further comprising the step of subjecting the metal substrate to an activating treatment, prior to the step of plating the metal substrate with iron or an iron containing alloy.
Claim 5
Dependent Claim 40 words
The method of claim 2, wherein the metal substrate is an iron alloy and is subjected to a treatment in an acid containing bath prior to the step of plating the metal substrate with iron or an iron containing alloy.
Claim 6
Dependent Claim 16 words
The method of claim 4, wherein said acid of said acid containing bath is hydrochloric acid.
Claim 7
Dependent Claim 16 words
The method of claim 4, wherein said acid of said acid containing bath is sulfuric acid.
Claim 8
Dependent Claim 21 words
The method of claim 4, wherein said acid containing bath and said iron salt containing bath are essentially the same bath.
Claim 9
Dependent Claim 19 words
The method of claim 3, wherein said activating treatment is conducted in said chromic acid bath containing a halide.
Claim 10
Dependent Claim 16 words
The method of claim 3, wherein said activating treatment comprises electrolytic treatment of said metal substrate.
Claim 11
Dependent Claim 16 words
The method of claim 3, wherein said activating treatment comprises immersion treatment of said metal substrate.
Claim 12
Dependent Claim 53 words
The method of claim 1, wherein said metal substrate is iron or an iron containing alloy and further comprising the the step of subjecting the iron containing deposit on the substrate metal to an anodic treatment in a acid containing bath prior to the step of depositing chromium on the plated metal substrate.

References Cited (Backward Citations)

US3806429A Cited
US4234396A Cited
US4188459A Cited
US4366034A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-05-22 1987-11-21 1988-05-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-05-22 1991-11-21 1992-05-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-05-22 1995-11-21 1996-05-22 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag