Patent US3753720A successfully refreshed from Google Patents.
US3753720A
Expired / Lapsed
US
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Solder resistant photopolymer compositions
Assignee: WR Grace and Co Conn
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Filing: 1972-01-10
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Granted: 1973-08-21
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Expires: 1992-01-10
Abstract
Abstract This invention relates to heat and solder resistant, photopolymer compositions which can be imaged and developed and processes of using same. The solder resistant, photocurable, photoresist compositions comprise a polythiol, polyene and silicone oil. The liquid compositions, when applied to a printed circuit board and cured imagewise as desired to a solid in the presence of a free radical generator, permit passage of the board through a bath of molten solder to secure electrical components thereto. When the free radical generator is actinic radiation, e.g., UV light, a curing rate accelerator, e.g., benzophenone is usually added to the composition.
Inventors
- 👤 D Kramm
- 👤 W Schaeffer
- 👤 H Kloczewski
- 👤 J Moyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:06
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/22; H05K3/28; H05K3/285; H05K3/287; B; B23; B23K; B23K35/00; B23K35/22; B23K35/224; C; C08; C08G; C08G75/00; C08G75/02; C08G75/04; C08G75/045; C08G75/12; G; G03; G03F; G03F7/00; G03F7/004; G03F7/027; G03F7/0275; Y; Y10; Y10S; Y10S430/00; Y10S430/1053; Y10S430/1055; Y10S430/114; Y10S430/117; Y10S430/122
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
16 words
about one to 49 parts by weight of a polyene selected from the group consisting of:
Claim 2
Dependent Claim
25 words
The composition of claim 2 including 0.05 to 10 parts by weight based on the weight of (1) and (2) of a photocuring rate accelerator
Claim 3
Dependent Claim
42 words
The composition of claim 1 including 0.1 to 5.0 parts per 100 parts by weight of (1) and (2) of a stabilizer selected from the group consisting essentially of phosphorous acid; pyrogallol; Beta (4-hydroxy-3, 5-di-t-butylphenyl) propionate; 2, 6- ditertiary-butyl-4-methylphenol and mixtures thereof.
Claim 4
Dependent Claim
17 words
five to 20 parts by weight based on the weight of (1) and (2) of silicone oil.
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) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |