US4810412A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Azeotropic compositions of 1,1-difluoro-2,2-dichloroethane and methanol or ethanol
Assignee: EIDP Inc
•
Filing: 1988-04-11
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Granted: 1989-03-07
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Expires: 2008-04-11
Abstract
Abstract Azeotropic mixtures of 1,1-difluoro-2,2-dichloroethane (HCFC-132a) with methanol or ethanol, the azeotropic mixtures being useful in solvent cleaning applications.
Inventors
- 👤 Abid N. Merchant
- 👤 Jill M. Redenbaugh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:39
CPC Classifications
H; H05; H05K; H05K3/00; C; C11; C11D; C11D7/00; C11D7/50; C11D7/5036; C11D7/5068; C11D7/5077; C11D7/5081
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
15 words
The azeotrope composition comprising about 87-92 weight percent 1,1-difluoro-2,2-dichloroethane and about 13-8 weight percent methanol.
Claim 2
Dependent Claim
15 words
The azeotrope composition comprising about 87-92 weight percent 1,1-difluoro-2,2-dichloroethane and about 13-8 weight percent methanol.
Claim 3
Dependent Claim
22 words
The azeotrope or composition of claim 1 wherein the composition is about 94-97 weight percent 1,1-difluoro-2,2-dichloroethane and about 6-3 weight percent ethanol.
Claim 4
Dependent Claim
21 words
The azeotrope composition of claim 1 wherein the composition is about 89.5 weight percent 1,1-difluoro-2,2-dichloroethane and about 10.5 weight percent methanol.
Claim 5
Dependent Claim
21 words
The azeotrope composition of claim 1 wherein the composition has a boiling point of about 54° C. at substantially atmospheric pressure.
Claim 6
Dependent Claim
21 words
The azeotrope composition of claim 2 wherein the composition is about 95.4 weight percent 1,1-difluoro-2,2-dichloroethane and about 4.6 weight percent ethanol.
Claim 7
Dependent Claim
21 words
The azeotrope composition of claim 2 wherein the composition has a boiling point of about 58° C. at substantially atmospheric pressure.
Claim 8
Dependent Claim
19 words
A process for cleaning a solid surface which comprises treating said surface with the azeotrope composition of claim 1.
Claim 9
Dependent Claim
21 words
The process of claim 7 wherein the solid surface is a printed circuit board contaminated with solder flux and flux residue.
Claim 10
Dependent Claim
12 words
The process of claim 7 wherein the solid surface is a metal.
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) | 1992-03-06 | 1992-09-05 | 1993-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-06 | 1996-09-05 | 1997-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-06 | 2000-09-05 | 2001-03-07 | $7700.00 | Window Closed / Lapsed |