Claims
- 1. A magnetic recording medium comprising a substrate having coated thereon a magnetic recording layer comprising a magnetic pigment dispersed in a polymeric binder, said binder comprising an electron-beam curable polyurethane polymer, wherein said polyurethane polymer has in its backbone:
- (a) segments derived from an unsaturated diol, wherein the unsaturated diol is N,N-bis(2-hydroxyethyl), N'(2-methacryloxy-ethyl)urea;
- (b) segments of a macroglycol compound having a molecular weight of from 500 to 5,000; and
- (c) segments of a short-chain diol selected from the group consisting of an aliphatic diol having 2 to 8 carbon atoms and a carbocyclic diol having 6 to 10 carbon atoms.
- 2. The magnetic recording medium of claim 1, wherein the unsaturated diol is incorporated into the backbone of the polyurethane polymer in a sufficient amount to provide incorporation of at least one carbon-carbon double bond every 2,000 to 3,000 molecular weight units of the polyurethane polymer.
- 3. The magnetic recording medium of claim 1, further comprising segments in the polymer backbone derived from an organic diisocyanate having a number average molecular weight of from about 168 to 450.
Parent Case Info
This is a continuation of application Ser. No. 07/685,829, filed Apr. 15, 1991 now abandoned, which is a division of application Ser. No. 07/184,834 filed Apr. 22, 1988 now U.S. Pat. No. 5,028,683.
US Referenced Citations (21)
Foreign Referenced Citations (4)
Number |
Date |
Country |
0062995 |
Oct 1982 |
EPX |
8028480 |
Aug 1978 |
JPX |
8201099 |
Apr 1982 |
WOX |
2084589 |
Apr 1982 |
GBX |
Non-Patent Literature Citations (1)
Entry |
Rand, William M., Jr., "Electron Curing of Magnetic Coatings", Radiation Curing, Feb. 1983, pp. 26-28 and 30-31. |
Divisions (1)
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Number |
Date |
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Parent |
184834 |
Apr 1988 |
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Continuations (1)
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Number |
Date |
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Parent |
685829 |
Apr 1991 |
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