Patent US3939016A successfully refreshed from Google Patents.
US3939016A
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Aqueous quenching medium containing salts of polymeric materials
Assignee: Toho Chemical Industry Co Ltd
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Filing: 1973-10-02
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Granted: 1976-02-17
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Expires: 1993-10-02
Abstract
Abstract A novel quenching medium for steel is provided. The quenching medium is a 0.5-10 wt. % aqueous solution of polyacrylic acid, polymethacrylic acid, a copolymer of acrylic acid and methacrylic acid, or a salt thereof. Intrinsic viscosity [ eta ] of the polymer is from 0.010 to 0.050 l/g. The quenching medium is superior in various quenching characteristics to conventional quenching media.
Inventors
- 👤 Takashi Tokuue
- 👤 Takashi Kato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:37
CPC Classifications
C; C21; C21D; C21D1/00; C21D1/56; C21D1/60
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
72 words
A quenching medium comprising an aqueous solution containing 0.4 to 10% by weight of a polymer mixture consisting essentially of 40 to 60% by weight of sodium or potassium polyacrylate and 60 to 40% by weight of a sodium or potassium salt of a copolymer of acrylic acid and methacrylic acid, said polyacrylate and copolymer of acrylic acid and methacrylic acid each having an intrinsic viscosity [η] of 0.010 to 0.050 l/g.
Claim 2
Dependent Claim
72 words
A quenching medium comprising an aqueous solution containing 0.4 to 10% by weight of a polymer mixture consisting essentially of 40 to 60% by weight of sodium or potassium polyacrylate and 60 to 40% by weight of a sodium or potassium salt of a copolymer of acrylic acid and methacrylic acid, said polyacrylate and copolymer of acrylic acid and methacrylic acid each having an intrinsic viscosity [η] of 0.010 to 0.050 l/g.
Claim 3
Dependent Claim
27 words
The quenching medium of claim 1 wherein said polyacrylate and copolymer of acrylic acid and methacrylic acid having an intrinsic viscosity [η] of 0.020 to 0.045 l/g.
Claim 4
Dependent Claim
23 words
The quenching medium of claim 1 wherein the concentration of said polymer mixture in the aqueous solution is 0.5 to 6.0% by weight.
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) | 1979-02-16 | 1979-08-18 | 1980-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-16 | 1983-08-18 | 1984-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-16 | 1987-08-18 | 1988-02-17 | $7700.00 | Window Closed / Lapsed |