US4647501A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording medium
Assignee: Fujifilm Holdings Corp
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Filing: 1985-12-24
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Granted: 1987-03-03
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Expires: 2005-12-24
Abstract
Abstract A magnetic recording material, which comprises a non-magnetic support having provided on one side thereof a magnetic layer and on the other side thereof a backing layer is disclosed. The binder of the backing layer is comprised of a combination of a cellulose resin, a vinylidene chloride resin, a polyurethane resin and a polyisocyanate. Use of the backing layer increases the durability of the tape and aids in preventing drop out.
Inventors
- 👤 Nobutaka Yamaguchi
- 👤 Shinobu Iida
- 👤 Norio Nasu
- 👤 Katsumi Ryoke
- 👤 Toshimitu Okutu
- 👤 Kenichi Masuyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:39
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/735; G11B5/7356; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/25; Y10T428/31504; Y10T428/31551; Y10T428/31565; Y10T428/31573; Y10T428/3158; Y10T428/31609
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
141 words
A magnetic recording material. comprising: a non-magnetic support base having provided on one side thereof; a magnetic layer comprised of ferromagnetic particles dispersed therein; and a backing layer provided on the opposite side of the support base, the backing layer being comprised of a cellulose resin in an amount of about 1 to 80% by weight and a vinylidene chloride resin in an amount of about 2 to 80% by weight, a polyurethane resin in an amount of about 5 to 90% by weight and a polyisocyanate in an amount of about 5 to 90% by weight based on the total weight of binders in the backing layer, wherein the backing layer is further comprised of carbon black particles dispersed therein, and wherein the carbon black particles have a particle size in the range of about 10 mμ to 150 mμ.
Claim 2
Dependent Claim
141 words
A magnetic recording material. comprising: a non-magnetic support base having provided on one side thereof; a magnetic layer comprised of ferromagnetic particles dispersed therein; and a backing layer provided on the opposite side of the support base, the backing layer being comprised of a cellulose resin in an amount of about 1 to 80% by weight and a vinylidene chloride resin in an amount of about 2 to 80% by weight, a polyurethane resin in an amount of about 5 to 90% by weight and a polyisocyanate in an amount of about 5 to 90% by weight based on the total weight of binders in the backing layer, wherein the backing layer is further comprised of carbon black particles dispersed therein, and wherein the carbon black particles have a particle size in the range of about 10 mμ to 150 mμ.
Claim 3
Dependent Claim
23 words
A magnetic recording material as claimed in claim 1, wherein the particles size is in the range of 50 mμ to 120 mμ.
Claim 4
Dependent Claim
22 words
A magnetic recording material as claimed in claim 1, wherein the cellulose resin is substantially insoluble with respect to water and alcohols.
Claim 5
Dependent Claim
47 words
A magnetic recording material as claimed in claim 1, wherein the vinylidene chloride resin is a vinyl chloride-vinylidene chloride copolymer, vinylidene chloride-acrylonitrile copolymer, acrylic acid ester-vinylidene chloride copolymer, methacrylic acid ester-vinylidene chloride copolymers, vinylidene chloride-acrylonitrile-vinyl alcohol copolymer or a resin prepared using vinylidene chloride as a monomer.
Claim 6
Dependent Claim
24 words
A magnetic recording material as claimed in claim 1, wherein the polyurethane resin has a molecular weight in the range of 10,000 to 200,000.
Claim 7
Dependent Claim
68 words
A magnetic recording material as claimed in claim 1, wherein the backing layer is comprised of a cellulose resin in an amount of about 5 to 50% by weight, a vinylidene chloride resin in an amount of about 5 to 60% by weight, a polyurethane resin in an amount of about 10 to 80% by weight, and a polyisocyanate in an amount of 10 to 80% by weight.
Claim 8
Dependent Claim
69 words
A magnetic recording material as claimed in claim 1, wherein the backing layer is comprised of a cellulose resin in an amount of about 10 to 30% by weight, a vinylidene chloride resin in an amount of about 10 to 40% by weight, a polyurethane resin in an amount of about 20 to 50% by weight, and a polyisocyanate in an amount of about 20 to 50% by weight.
Claim 9
Dependent Claim
141 words
A magnetic recording material, comprising: a non-magnetic support base having provided on one side thereof; a magnetic layer comprised of ferromagnetic particles dispersed therein; and a backing layer provided on the opposite side of the support base, wherein the backing layer consists essentially of a cellulose resin in an amount of about 1 to 80% by weight, a vinylidene chloride resin in an amount of about 2 to 80% by weight, a polyurethane resin in an amount of about 5 to 90% by weight and a polyisocyanate in an amount of about 5 to 90% by weight, based on the total weight of binders in the backing layer, wherein the backing layer is further comprised of carbon black particles dispersed therein, and wherein the carbon black particles have a particle size in the range of about 10 mμ to 150 mμ.
Claim 10
Dependent Claim
141 words
A magnetic recording material, comprising: a non-magnetic support base having provided on one side thereof; a magnetic layer comprised of ferromagnetic particles dispersed therein; and a backing layer provided on the opposite side of the support base, wherein the backing layer consists essentially of a cellulose resin in an amount of about 1 to 80% by weight, a vinylidene chloride resin in an amount of about 2 to 80% by weight, a polyurethane resin in an amount of about 5 to 90% by weight and a polyisocyanate in an amount of about 5 to 90% by weight, based on the total weight of binders in the backing layer, wherein the backing layer is further comprised of carbon black particles dispersed therein, and wherein the carbon black particles have a particle size in the range of about 10 mμ to 150 mμ.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-03-02 | 1990-09-01 | 1991-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-02 | 1994-09-01 | 1995-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-02 | 1998-09-01 | 1999-03-03 | $7700.00 | Window Closed / Lapsed |