Patent US3713902A successfully refreshed from Google Patents.
US3713902A
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US
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Process for manufacturing zinc coated steel sheet, and steel sheet obtained by this process
Assignee: KONINKLIJKE HOOGOVENS EN STAAL
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Filing: 1970-06-16
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Granted: 1973-01-30
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Expires: 1990-06-16
Abstract
Abstract Phosphated zinc coated steel sheet characterized by a phosphate layer with a mass of less than 4 g/m2 and with a structure which closes the zinc layer 90 percent or more, and process for improving phosphating of zinc coated steel sheet which essentially comprises passing the zinc coated sheet between elastically surfaced rollers prior to phosphating.
Inventors
- 👤 H Vrijburg
- 👤 C Bijl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:05
CPC Classifications
C; C23; C23C; C23C22/00; C23C22/78; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12535; Y10T428/12583; Y10T428/12771; Y10T428/12785; Y10T428/12792; Y10T428/12799
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
94 words
An improved process for manufacturing phosphated zinc coated steel sheet, which process comprises the step of a. effecting phosphating of the zinc coated steel sheet by submerging the same in a phosphating solution, wherein the improvement comprises b. passing the zinc coated steel sheet, before subjecting it to step (a), between at least one pair of rolls with surfaces of rubbery material having a shore hardness of 40* to 90*, and c. causing the said rolls during step (b) to exert on the sheet a force of at least 0.4 Kg/cm of roll length.
Claim 2
Dependent Claim
94 words
An improved process for manufacturing phosphated zinc coated steel sheet, which process comprises the step of a. effecting phosphating of the zinc coated steel sheet by submerging the same in a phosphating solution, wherein the improvement comprises b. passing the zinc coated steel sheet, before subjecting it to step (a), between at least one pair of rolls with surfaces of rubbery material having a shore hardness of 40* to 90*, and c. causing the said rolls during step (b) to exert on the sheet a force of at least 0.4 Kg/cm of roll length.
Claim 3
Dependent Claim
32 words
An improved process as claimed in claim 1, wherein: e. in step (a) the submergence of the rolled sheet is maintained only about 3 seconds and at a temperature of about 70*C.
Claim 4
Dependent Claim
35 words
An improved process as claimed in claim 1, in which: e. step (b) is practiced by passing the zinc coated sheet between such rolls 3 or 4 times before it is subjected to step (a).
Claim 5
Dependent Claim
32 words
An improved process as claimed in claim 1, wherein: e. step (c) is practiced by causing the rolls to exert on the sheet a force of about 20 Kg/cm of roll length.
Claim 6
Dependent Claim
28 words
An improved process as claimed in claim 1, wherein: e. step (b) is practiced with rolls with rubbery surfaces having a shore hardness of 60* to 80* .
Claim 7
Dependent Claim
40 words
A phosphated zinc coated steel sheet produced by the process of claim 1, said sheet having a phosphate layer with a mass of less than 4 g/m2 and a structure which is over 90 percent closed over the zinc layer.
References Cited (Backward Citations)
US2373433A
Cited
US2795518A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |