Claims
- 1. A magnetic recording medium which has a magnetic layer having a binder composition comprising a sulfobetaine-containing resin which is a urethane resin, and wherein the sulfobetaine content in the resin amounts to about 1 to 1,000 equivalents/10.sup.6 g.
- 2. The magnetic recording medium as claimed in claim 1, which is prepared by coating a nonmagnetic support with a binder composition comprising a sulfobetaine-containing resin in an amount such that the film thickness after drying is about 0.1 to 50 .mu.m.
- 3. In a magnetic recording media binder composition, the improvement which comprises employing as an essential component of the composition, a sulfobetaine-containing resin which is a urethane resin, and wherein the sulfobetaine content in the resin amounts to about 1 to 1,000 equivalents/10.sup.6 g.
- 4. The binder as claimed in claim 3, wherein the urethane resin is one obtained by the reaction of a polyisocyanate with a polyhydroxy compound, a part of the polyhydroxy compound being replaced with a sulfobetaine-containing polyhydroxy compound.
- 5. The binder as claimed in claim 4, wherein the sulfobetaine-containing polyhydroxy compound is a reaction product from a tertiary amine having two or more hydroxy groups and a sultone of the general formula ##STR8## wherein --R-- is a straight or branched alkylene group having a carbon number of 1 to 20 and n is an integer of 2 to 20.
- 6. The binder as claimed in claim 3, wherein the sulfobetaine-containing resin is used in combination with a thermoplastic resin having a softening point not lower than 150.degree. C., an average molecular weight of 10,000 to 200,000 and polymerization degree of about 200 to 2,000.
- 7. The binder as claimed in claim 3, wherein the sulfobetaine-containing resin is used in combination with a polyisocyanate as a curing agent.
Priority Claims (1)
Number |
Date |
Country |
Kind |
63-130970 |
May 1988 |
JPX |
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Parent Case Info
This application is a continuation of now abandoned application Ser. No. 356,324, filed May 23, 1989, now abandoned.
US Referenced Citations (8)
Foreign Referenced Citations (2)
Number |
Date |
Country |
58-179936 |
Oct 1983 |
JPX |
62-88134 |
Apr 1987 |
JPX |
Non-Patent Literature Citations (1)
Entry |
"Polyurethannes a proprietes emulsifiantes et electrolytiques" Jean--Francois Gerard, Makromol Chem. 189, 1693-1717 Jul. 1988. |
Continuations (1)
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Number |
Date |
Country |
Parent |
356324 |
May 1989 |
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