US3972765A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making laminate sheets for printed circuit boards
Assignee: Resonac Corp
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Filing: 1974-03-05
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Granted: 1976-08-03
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Expires: 1994-03-05
Abstract
Abstract In preparing an epoxy resin laminate sheet by impregnating a nonwoven fabric of glass fiber with an epoxy resin to form a prepreg, laminating a predetermined number of so formed prepregs and pressing, while heating, the laminate, when the nonwoven fabric of glass fiber to be used as a substrate is treated with a liquid mixture containing a water-soluble phenol resin and a silane coupler prior to the impregnation step, a laminate sheet suitable for formation of a printed circuit board can be obtained at a low manufacturing cost. The so formed laminate sheet not only has excellent heat resistance, drilling workability and punching workability at room temperature but also is characterized by such an excellent property that when it is subjected to the boiling water treatment, the degree of reduction of electric properties such as the insulation resistance is very small and whitening of the substrate is not caused to occur.
Inventors
- 👤 Terutake Kondo
- 👤 Syunya Yokozawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:01
CPC Classifications
C; C03; C03C; C03C25/00; C03C25/10; C03C25/24; C03C25/26; C03C25/32; C03C25/36; H; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/0313; H05K1/0353; H05K1/0366; H05K2201/00; H05K2201/01; H05K2201/0137; H05K2201/0166; H05K2201/02; H05K2201/0203; H05K2201/0206; H05K2201/0239; H05K2201/0275; H05K2201/0293; H05K3/00; H05K3/38; H05K3/389; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/2962; Y10T428/2971; Y10T428/31504; Y10T428/31551; Y10T428/31609; Y10T428/31612; Y10T428/31627; Y10T428/31652; Y10T428/31663; Y10T442/00; Y10T442/60; Y10T442/659; Y10T442/67
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
111 words
In a method of making an epoxy-glass laminate sheet comprising a nonwoven fabric of glass fiber as a substrate, which comprises the steps of impregnating a nonwoven fabric of glass fiber with an epoxy resin, drying the resulting fabric of glass fiber to form a prepreg, laminating a predetermined number of so formed prepregs, and then pressing, while heating, the laminate to obtain an epoxy-glass laminate sheet for production of a printed circuit board, the improvement wherein the nonwoven fabric of glass fibers is treated with a liquid mixture containing a silane coupler and a water-soluble phenol resin prior to the step of impregnating the nonwoven fabric with the epoxy resin.
Claim 2
Dependent Claim
111 words
In a method of making an epoxy-glass laminate sheet comprising a nonwoven fabric of glass fiber as a substrate, which comprises the steps of impregnating a nonwoven fabric of glass fiber with an epoxy resin, drying the resulting fabric of glass fiber to form a prepreg, laminating a predetermined number of so formed prepregs, and then pressing, while heating, the laminate to obtain an epoxy-glass laminate sheet for production of a printed circuit board, the improvement wherein the nonwoven fabric of glass fibers is treated with a liquid mixture containing a silane coupler and a water-soluble phenol resin prior to the step of impregnating the nonwoven fabric with the epoxy resin.
Claim 3
Dependent Claim
23 words
A method according to claim 1 wherein said liquid mixture contains as a solvent water or a mixture of water and an alcohol.
Claim 4
Dependent Claim
24 words
A method according to claim 1 wherein said silane coupler is a member selected from the group consisting of γ-ethylenediaminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane and γ-chloropropyltrimethoxysilane.
Claim 5
Dependent Claim
40 words
A method according to claim 1 wherein said phenol resin is one prepared by reacting phenol with formaldehyde in the presence of a catalyst at 40° - 100°C. for 2 - 50 hours and composed mainly of dimers and trimers.
Claim 6
Dependent Claim
31 words
A method according to claim 1 wherein said nonwoven fabric of glass fiber is one in which a chemical or resin is used as a medium for bonding the glass fiber.
Claim 7
Dependent Claim
29 words
A method according to claim 1 wherein said nonwoven fabric of glass fiber is one in which cellulose fibers are incorporated as a medium for bonding the glass fibers.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-03 | 1980-02-02 | 1980-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-03 | 1984-02-02 | 1984-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-03 | 1988-02-02 | 1988-08-03 | $7700.00 | Window Closed / Lapsed |