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US4298407A Expired / Lapsed US ⏱️ 0.0 years remaining

Flux treated solder powder composition

Assignee: EIDP Inc
•
Filing: 1980-08-04
•
Granted: 1981-11-03
•
Expires: 2000-08-04
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Abstract

Abstract Tin alloy solder powder compositions comprising finely divided particles of the alloy coated with a thin continuous layer of organic flux sufficient to lower the electrical conductivity and to obscure the eutectic domains on the surface of the alloy particles.

Inventors

  • 👤 Barry E. Taylor

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 15:39
CPC Classifications
B; B23; B23K; B23K35/00; B23K35/02; B23K35/0222; B23K35/0244; B23K35/22; B23K35/36; H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/3465; H05K3/3485

Claims Analysis

Total Claims: 31
Claim 1
Independent Claim 45 words
A tin alloy solder powder composition comprising finely divided particles of tin alloy coated with a thin substantially continuous layer of an organic flux, sufficient to lower the electrical conductivity of and to obscure the eutectic metal domains on the surface of the alloy particles.
Claim 2
Dependent Claim 45 words
A tin alloy solder powder composition comprising finely divided particles of tin alloy coated with a thin substantially continuous layer of an organic flux, sufficient to lower the electrical conductivity of and to obscure the eutectic metal domains on the surface of the alloy particles.
Claim 3
Dependent Claim 23 words
The composition of claim 1 in which the flux is selected from the group consisting of organic acids, esters, amines, alcohols and phosphates.
Claim 4
Dependent Claim 13 words
The composition of claim 1 in which the flux is an organic acid.
Claim 5
Dependent Claim 14 words
The composition of claim 3 in which the organic acid is a dicarboxylic acid.
Claim 6
Dependent Claim 18 words
The composition of claim 4 in which the dicarboxylic acid is salicylic acid, succinic acid, or mixtures thereof.
Claim 7
Dependent Claim 20 words
The composition of claim 1 in which the organic flux coating comprises 0.1 to 10% of the total particle weight.
Claim 8
Dependent Claim 26 words
The composition of claim 6 for use with organic solvent cleanup in which the flux coating is 0.1 to 1.0% by weight of the coated particle.
Claim 9
Dependent Claim 49 words
A screen-printable tin alloy solder paste composition comprising finely divided particles of tin alloy coated with a thin substantially continuous layer of flux, sufficient to lower the electrical conductivity of and to obscure the eutectic metal domains on the surface of the alloy particles, dispersed in an organic medium.
Claim 10
Dependent Claim 49 words
A screen-printable tin alloy solder paste composition comprising finely divided particles of tin alloy coated with a thin substantially continuous layer of flux, sufficient to lower the electrical conductivity of and to obscure the eutectic metal domains on the surface of the alloy particles, dispersed in an organic medium.
Claim 11
Dependent Claim 23 words
The composition of claim 8 in which the flux is selected from the group consisting of organic acids, esters, amines, alcohols and phosphates.
Claim 12
Dependent Claim 13 words
The composition of claim 8 in which the flux is an organic acid.
Claim 13
Dependent Claim 14 words
The composition of claim 10 in which the organic acid is a dicarboxylic acid.
Claim 14
Dependent Claim 18 words
The composition of claim 11 in which the dicarboxylic acid is salicylic acid, succinic acid, or mixtures thereof.
Claim 15
Dependent Claim 20 words
The composition of claim 8 in which the organic flux coating comprises 0.1 to 10% of the total particle weight.
Claim 16
Dependent Claim 26 words
The composition of claim 13 for use with organic solvent cleanup in which the flux coating is 0.1 to 1.0% by weight of the coated particle.
Claim 17
Dependent Claim 28 words
The composition of claim 8 containing 0.3% by weight basis total composition of an organic amine which is a solvent for lead oxide and the alloy is tin/lead.
Claim 18
Dependent Claim 25 words
The composition of claim 15 for use with organic solvent cleanup in which the flux coating comprises 0.1 to 1.0% of the coated particle weight.
Claim 19
Dependent Claim 17 words
The composition of claim 15 in which the amine is a C 1-8 alkanol mono- to tetra-amine.
Claim 20
Dependent Claim 12 words
The composition of claim 16 in which the organic amine is triethanolamine.
Claim 21
Dependent Claim 17 words
The composition of claim 16 in which the amine is a C 1-18 alkyl mono- to tetra-amine.
Claim 22
Independent Claim 49 words
The method for coating finely divided particles of tin alloy with a thin substantially continuous layer of organic flux comprising intimately admixing the particles with the flux for a time sufficient to reduce the electrical conductivity of the obscure the eutectic domains of the surface of the alloy particles.
Claim 23
Independent Claim 49 words
The method for coating finely divided particles of tin alloy with a thin substantially continuous layer of organic flux comprising intimately admixing the particles with the flux for a time sufficient to reduce the electrical conductivity of the obscure the eutectic domains of the surface of the alloy particles.
Claim 24
Dependent Claim 19 words
The method of claim 20 in which the flux coating comprises 0.1 to 10% of the total particle weight.
Claim 25
Dependent Claim 14 words
The method of claim 20 which is carried out by means of bead milling.
Claim 26
Dependent Claim 60 words
A process for joining two solderable metal surfaces comprising (a) applying to at least one of the surfaces a film of the tin alloy paste composition of claim 8, (b) applying heat to the surfaces to volatilize organic medium therefrom and to reflow the alloy into contact with both surfaces, and (c) cooling the resultant assemblage to solidify the alloy.
Claim 27
Dependent Claim 14 words
The process of claim 23 in which the paste is applied by screen printing.
Claim 28
Dependent Claim 31 words
The process of claim 23 in which the flux is applied by lamination, imagewise exposure, and development of a dry film photoresist having the solder paste dispersed in the photosensitive layer.
Claim 29
Dependent Claim 13 words
The process of claim 23 in which the paste is applied by stenciling.
Claim 30
Dependent Claim 14 words
The process of claim 23 in which the paste is applied by syringe dispensing.
Claim 31
Dependent Claim 15 words
The process of claim 23 in which the paste is applied by rotating wheel transfer.

References Cited (Backward Citations)

US2898255A Cited
US3436278A Cited
US3617345A Cited
JPS4634211B1 Cited
JPS4926826A Cited
JPS5021308A Cited
US4168996A Cited
US4165244A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-11-02 1985-05-04 1985-11-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-11-02 1989-05-04 1989-11-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-11-02 1993-05-04 1993-11-03 $7700.00 Window Closed / Lapsed

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