US4297148A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Masonry cleaning process and composition
Assignee: Individual
•
Filing: 1980-04-14
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Granted: 1981-10-27
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Expires: 2000-04-14
Abstract
Abstract An aqueous composition for cleaning masonry containing sulphuric acid, hydrofluoric acid, chromic acid and a water miscible wetting agent.
Inventors
- 👤 Panagiotis Zervopoulos
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:49
CPC Classifications
C; C11; C11D; C11D3/00; C11D3/02; C11D3/04; C11D3/042
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
49 words
A cleaning composition suitable for cleaning masonry which comprises, by weight, about 8 to 30% sulphuric acid; about 23 to 30% hydrogen fluoride; about 0.1 to 0.2% chromic acid; about 0.9 to 1.8% water miscible wetting agent, and water in such amount to constitute the remainder of the composition.
Claim 2
Dependent Claim
49 words
A cleaning composition suitable for cleaning masonry which comprises, by weight, about 8 to 30% sulphuric acid; about 23 to 30% hydrogen fluoride; about 0.1 to 0.2% chromic acid; about 0.9 to 1.8% water miscible wetting agent, and water in such amount to constitute the remainder of the composition.
Claim 3
Dependent Claim
21 words
A cleaning composition as claimed in claim 1 which contains, by weight, about 27% sulphuric acid and about 29% hydrogen fluoride.
Claim 4
Dependent Claim
23 words
A cleaning composition as claimed in claim 1 or 2 diluted with up to 6 parts of water to 1 part of composition.
Claim 5
Independent Claim
62 words
A method of cleaning masonry surfaces comprising: applying to said surface, for a predetermined time sufficient to loosen deposits therefrom, a composition comprising, by weight, about 8 to 30% sulphuric acid; about 23 to 30% hydrogen fluoride; about 0.1 to 0.2% chromic acid; about 0.9 to 1.8% water miscible wetting agent, and the balance water, and then washing said surface with water.
Claim 6
Independent Claim
62 words
A method of cleaning masonry surfaces comprising: applying to said surface, for a predetermined time sufficient to loosen deposits therefrom, a composition comprising, by weight, about 8 to 30% sulphuric acid; about 23 to 30% hydrogen fluoride; about 0.1 to 0.2% chromic acid; about 0.9 to 1.8% water miscible wetting agent, and the balance water, and then washing said surface with water.
Claim 7
Dependent Claim
21 words
A method as claimed in claim 4, in which said composition contains, by weight, 27% sulphuric acid and 29% hydrogen fluoride.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-10-26 | 1985-04-27 | 1985-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-26 | 1989-04-27 | 1989-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-26 | 1993-04-27 | 1993-10-27 | $7700.00 | Window Closed / Lapsed |