Magnetic recording medium

• US 4,555,449 A
• Filed: 02/09/1984
• Issued: 11/26/1985
• Est. Priority Date: 02/09/1984
• Status: Expired due to Term

• Current Assignee: Union Carbide Corporation Old Ridgebury Road Danbury CT 06817
• Original Assignee: Union Carbide Corporation (Dow, Inc.)
• Inventors: Koleske, Joseph V., Kwiatkowski, George T., Peacock, Glenn S.
• Primary Examiner(s): Robinson, Ellis P.
• Application Number:
  US06/578,422
• Time in Patent Office: 656 Days
• Field of Search: 427/44, 427/128, 428/694, 428/900, 428/423.1, 428/423.7, 428/522, 428/411.1, 428/695, 360/134-136, 252/62.54
• US Class Current: 428/411.1
• CPC Class Codes: G11B 5/702 characterised by the bonding agent
• CPC Class Codes: Y10S 428/90 Magnetic feature
• CPC Class Codes: Y10T 428/31504 Composite [nonstructural laminate]
• CPC Class Codes: Y10T 428/31551 Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• CPC Class Codes: Y10T 428/31565 Next to polyester [polyethylene terephthalate, etc.]
• CPC Class Codes: Y10T 428/31935 Ester, halide or nitrile of addition polymer

Abstract

Described herein is a magnetic recording medium comprising a substrate and a magnetic recording layer thereon comprising a cured binder and magnetic particles, the binder containing a blend of a thermoplastic polymer or polymers and a polyfunctional acrylate derivatives of a caprolactone-polyol or a polyester polyol.

Claims

1. A magnetic recording medium comprising a substrate and a magnetic recording layer thereon comprising a cured binder and magnetic particles, the binder containing a blend of a thermoplastic polymer or polymers and a polyfunctional acrylate derivative of a caprolactone-polyol characterized by the formula:

##STR7## wherein R₁ is hydrogen or methyl, R₂ is the residue of a caprolactone-polyol having an average molecular weight of from about 200 to about 10,000, m is an integer of 2 to 8 and n is an integer of 0 to 6, with the proviso that the sum of m+n is 8 or less.

2. A magnetic recording medium as defined in claim 1 wherein R₂ is the residue of a caprolactone polyol prepared by the reaction of epsilon-caprolactone with trimethylolpropane.

3. A magnetic recording medium as defined in claim 1 wherein R₂ is the residue of a caprolactone-polyol prepared by the reaction of epsilon-caprolactone with pentaerythritol.

4. A magnetic recording medium as defined in claim 1 wherein R₁ is hydrogen, m is 3 and n is 0.

5. A magnetic recording medium as defined in claim 1 wherein R₁ is hydrogen, m is 4 and n is 0.

6. A magnetic recording medium as defined in claim 1 wherein R₁ is hydrogen, m is 5 and n is 0.

7. A magnetic recording medium as defined in claim 1 wherein R₁ is hydrogen, m is 6 and n is 0.

8. A magnetic recording medium as defined in claim 1 wherein the thermoplastic polymer contains a polyurethane.

9. A magnetic recording medium as defined in claim 1 wherein the thermoplastic polymer contains a poly(hydroxyether).

10. A magnetic recording medium as defined in claim 1 wherein the thermoplastic polymer contains a vinyl chloride copolymer.

11. A magnetic recording medium as defined in claim 1 wherein the thermoplastic polymer is a mixture of a polyurethane, a poly(hydroxyether), and/or a vinyl copolymer.