US4410440A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyurethane magnetic disk coatings
Assignee: International Business Machines Corp
•
Filing: 1982-02-26
•
Granted: 1983-10-18
•
Expires: 2002-02-26
Abstract
Abstract A polyurethane coating material for magnetic recording disks which is composed of magnetic particles, solvent blends and a thermosetting binder system. The resins are made from blocked isocyanates or blocked polyisocyanates with polyacrylates which contain reactive hydrogens.
Inventors
- 👤 Ming Ko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:04
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/62; C08G18/6216; G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7021; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31551; Y10T428/31609
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
49 words
A magnetic recording coating composition comprising: a. 20-65 parts by weight of magnetic particles, b. a polymeric binder system for said particles containing 5-30 parts by weight of acrylic resins which contain reactive hydrogens, 5-30 parts by weight of blocked isocyanates, and 5-30 parts by weight of blocked polyisocyanates.
Claim 2
Dependent Claim
49 words
A magnetic recording coating composition comprising: a. 20-65 parts by weight of magnetic particles, b. a polymeric binder system for said particles containing 5-30 parts by weight of acrylic resins which contain reactive hydrogens, 5-30 parts by weight of blocked isocyanates, and 5-30 parts by weight of blocked polyisocyanates.
Claim 3
Dependent Claim
29 words
A magnetic recording coating composition in accordance with claim 1 in which said blocked isocyanate is a low molecular weight isocyanate with blocking agents of phenols, ketoximes or caprolactams.
Claim 4
Dependent Claim
35 words
A magnetic recording coating composition in accordance with claim 2 in which said resins include high or low molecular weight acrylic resins which have functional groups of hydroxyl groups, or amine groups or amide groups.
Claim 5
Dependent Claim
29 words
A magnetic recording coating composition in accordance with claim 1 including a blocked polyisocyanate which is blocked with oligomers or copolymers of tolylene diisocyanates, diphenylmethane diisocyanates or other isocyanates.
Claim 6
Dependent Claim
17 words
A magnetic recording composition in accordance with claim 1 including 20-70 parts by weight of solvent material.
References Cited (Backward Citations)
US4074012A
Cited
US3926826A
Cited
US3929659A
Cited
US4058646A
Cited
US4020236A
Cited
US4092256A
Cited
US4152485A
Cited
US4336308A
Cited
US4286022A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-17 | 1987-04-18 | 1987-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-17 | 1991-04-18 | 1991-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-17 | 1995-04-18 | 1995-10-18 | $7700.00 | Window Closed / Lapsed |