US4661173A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alloy-enriched solder cream
Assignee: McDonnell Douglas Corp
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Filing: 1986-07-25
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Granted: 1987-04-28
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Expires: 2006-07-25
Abstract
Abstract A soldering composition containing at least 85% and less than 90% by weight of finely divided solder metal and a minor portion of a vehicle for the solder metal, consisting essentially of a rosin-type flux, a thickening agent and a minor portion, about 2 to about 7%, of a fluorinated tertiary alkylamine, particularly a perfluorotrihexyl amine. During vapor-phase soldering, the amine component is washed from the solder composition, leaving solder metal, rosin-type flux and thickening agent, in the remaining composition, the composition at this stage containing about 90% solder metal, and yielding dense solder joints, essentially no solder balls, and minimal residue.
Inventors
- 👤 Felix Barajas
- 👤 Donald W. Bridges
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:34
CPC Classifications
B; B23; B23K; B23K35/00; B23K35/22; B23K35/24; B23K35/26; B23K35/262; B23K35/36; B23K35/3612
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
103 words
A solder composition especially adapted for soldering components in electronic circuits to form solder joints and essentially free of solder ball formation, which comprises at least 85% and less than 90% by weight of finely divided solder metal, and a minor portion of a vehicle for said solder metal consisting essentially of a rosin-type flux, a thickening agent and a fluorinated tertiary alkylamine which is semi-solid at room temperature, whereby during vapor-phase condensation soldering, said tertiary alkylamine is washed from the solder composition and the remaining solder composition comprises essentially about 90% of said solder metal and the remainder of the vehicle components.
Claim 2
Dependent Claim
103 words
A solder composition especially adapted for soldering components in electronic circuits to form solder joints and essentially free of solder ball formation, which comprises at least 85% and less than 90% by weight of finely divided solder metal, and a minor portion of a vehicle for said solder metal consisting essentially of a rosin-type flux, a thickening agent and a fluorinated tertiary alkylamine which is semi-solid at room temperature, whereby during vapor-phase condensation soldering, said tertiary alkylamine is washed from the solder composition and the remaining solder composition comprises essentially about 90% of said solder metal and the remainder of the vehicle components.
Claim 3
Dependent Claim
22 words
The solder composition of claim 1, said fluorinated tertiary alkylamine being a perfluorinated trialkyl amine containing from 4 to 8 carbon atoms.
Claim 4
Dependent Claim
13 words
The solder composition of claim 2, said perfluorinated trialkyl amine being perfluorotrihexyl amine.
Claim 5
Dependent Claim
26 words
The solder composition of claim 3, said perfluorotrihexyl amine being selected from the group consisting of the straight chain and branched chain isomers, and mixtures thereof.
Claim 6
Dependent Claim
42 words
The solder composition of claim 1, including a small amount of an organic brominated activator compound sufficient to react at soldering temperature with any lead oxide or tin oxide present in the solder metal, to convert said oxides to the corresponding bromides.
Claim 7
Dependent Claim
19 words
The solder composition of claim 5, said brominated activator compound selected from the group consisting of bromocyclohexane and bromocamphor.
Claim 8
Dependent Claim
26 words
The solder composition of claim 6, said brominated activator compound being present in an amount of about 0.1 to about 1% by weight of the composition.
Claim 9
Dependent Claim
18 words
The solder composition of claim 7, including a small amount of surfactant as scavenging agent for said bromides.
Claim 10
Dependent Claim
14 words
The solder composition of claim 1, said rosin-type flux comprising rosin and derivatives thereof.
Claim 11
Dependent Claim
12 words
The solder composition of claim 9, said rosin-type flux comprising abietic acid.
Claim 12
Dependent Claim
13 words
The solder composition of claim 9, said thickening agent being a thixotropic agent.
Claim 13
Dependent Claim
13 words
The solder composition of claim 11, said vehicle also containing an organic solvent.
Claim 14
Dependent Claim
39 words
The solder composition of claim 12, said vehicle, excluding said fluorinated amine, containing 0.5 to 10% of said thixotropic agent, 30 to 60% of said organic solvent and 2 to 65% of said flux, by weight of said vehicle.
Claim 15
Dependent Claim
25 words
The solder composition of claim 1, said solder metal being selected from the group consisting of tin, lead and silver, and alloys and mixtures thereof.
Claim 16
Dependent Claim
21 words
The solder composition of claim 14, the particle size of said solder metal ranging from about 0.5 to about 100 microns.
Claim 17
Dependent Claim
132 words
A solder composition especially adapted for soldering components in electronic circuits to form dense solder joints and essentially free of solder ball formation, and with minimal residue, which comprises about 85 to about 88% of finely divided solder metal, a minor portion of a vehicle for said solder metal, said vehicle consisting essentially of a rosin-type flux, a thickening agent and about 2 to about 7% by weight of said composition of a perfluorotrihexyl amine which is semi-solid at room temperature and which in conjunction with said thickening agent, confers a creamy consistency on the composition at room temperature, whereby during vapor-phase condensation soldering, said amine is washed from the solder composition, and the remaining solder composition comprises essentially about 90% of said solder metal and the remainder of the vehicle components.
Claim 18
Dependent Claim
132 words
A solder composition especially adapted for soldering components in electronic circuits to form dense solder joints and essentially free of solder ball formation, and with minimal residue, which comprises about 85 to about 88% of finely divided solder metal, a minor portion of a vehicle for said solder metal, said vehicle consisting essentially of a rosin-type flux, a thickening agent and about 2 to about 7% by weight of said composition of a perfluorotrihexyl amine which is semi-solid at room temperature and which in conjunction with said thickening agent, confers a creamy consistency on the composition at room temperature, whereby during vapor-phase condensation soldering, said amine is washed from the solder composition, and the remaining solder composition comprises essentially about 90% of said solder metal and the remainder of the vehicle components.
Claim 19
Dependent Claim
42 words
The solder composition of claim 16, including a small amount of an organic brominated activator compound sufficient to react at soldering temperature with any lead oxide or tin oxide present in the solder metal, to convert said oxides to the corresponding bromides.
Claim 20
Dependent Claim
39 words
The solder composition of claim 17, said brominated activator compound selected from the group consisting of bromocyclohexane and bromocamphor, said brominated activator compound being present in an amount of about 0.1 to about 1% by weight of the composition.
Claim 21
Dependent Claim
39 words
The solder composition of claim 18, said vehicle, excluding said fluorinated amine, containing 0.5 to 10% of said thickening agent, 30 to 60% of said organic solvent and 30 to 60% of said flux, by weight of said vehicle.
Claim 22
Dependent Claim
30 words
The solder composition of claim 19, said thickening agent being selected from the group consisting of castor oil and ethylene glycol monobutyl ether, and said rosin-type flux comprising abietic acid.
Claim 23
Dependent Claim
16 words
The solder composition of claim 20, said solvent being 2-butoxy (ethyl) ethyl acetate or isopropyl alcohol.
References Cited (Backward Citations)
US3712550A
Cited
US3684533A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-27 | 1990-10-27 | 1991-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-27 | 1994-10-27 | 1995-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-27 | 1998-10-27 | 1999-04-28 | $7700.00 | Window Closed / Lapsed |