Patent US4212701A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4212701A Expired / Lapsed US ⏱️ 0.0 years remaining

Process and composition of low toxicity for preparing aluminum surfaces for adhesive bonding

Assignee: United States Department of the Army
•
Filing: 1979-05-09
•
Granted: 1980-07-15
•
Expires: 1999-05-09
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The invention provides a process and composition of low toxicity for preparing aluminum surfaces for adhesive bonding. The process involves treating the aluminum with an etching composition composed of sulfuric acid, ferric sulfate and water. The invention eliminates the toxicity and pollution problems associated with the conventional chromate-type etching baths, reduces the contamination of the work place and environment to acceptable levels, and produces aluminum surfaces, which when adhesively bonded yield joints comparable in strength to those obtained by use of the conventional chromate-type etchant bath.

Inventors

  • 👤 William J. Russel
  • 👤 Elizabeth A. Garnis

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 20:21
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/20

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 67 words
A process for adhesive bonding of aluminum parts, wherein the aluminum parts prior to bonding are subjected to an etching process to produce a surface preparatory to adhesive bonding, which comprises contacting the aluminum part with an etchant composition consisting essentially of about 25 to 35 weight percent sulfuric acid 96% 5 weight percent to saturated solution of ferric sulfate 75% 50 to 70 weight percent water.
Claim 2
Dependent Claim 67 words
A process for adhesive bonding of aluminum parts, wherein the aluminum parts prior to bonding are subjected to an etching process to produce a surface preparatory to adhesive bonding, which comprises contacting the aluminum part with an etchant composition consisting essentially of about 25 to 35 weight percent sulfuric acid 96% 5 weight percent to saturated solution of ferric sulfate 75% 50 to 70 weight percent water.
Claim 3
Dependent Claim 35 words
A process according to claim 1, wherein the composition consists essentially of about 28 to 30 weight percent sulfuric acid 96% 10 to 14 weight percent ferric sulfate 75% 58 to 62 weight percent water.
Claim 4
Dependent Claim 17 words
A process according to claim 1, wherein the adhesive bonding is accomplished with an epoxy resin adhesive.
Claim 5
Dependent Claim 38 words
A composition for etching aluminum preparatory to adhesive bonding, which consists essentially of about 25 to 35 weight percent sulfuric acid 96% 5 weight percent to saturated solution of ferric sulfate 75% 50 to 70 weight percent water.
Claim 6
Dependent Claim 38 words
A composition for etching aluminum preparatory to adhesive bonding, which consists essentially of about 25 to 35 weight percent sulfuric acid 96% 5 weight percent to saturated solution of ferric sulfate 75% 50 to 70 weight percent water.
Claim 7
Dependent Claim 32 words
A composition according to claim 4, which consists essentially of 28 to 30 weight percent sulfuric acid 96% 10 to 14 weight percent ferric sulfate 75% 58 to 62 weight percent water.

References Cited (Backward Citations)

US2945778A Cited
US3140203A Cited
US3785866A Cited
US4100015A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-07-15 1984-01-14 1984-07-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-07-15 1988-01-14 1988-07-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-07-15 1992-01-14 1992-07-15 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag