Photographic material

• US 5,443,944 A
• Filed: 08/15/1994
• Issued: 08/22/1995
• Est. Priority Date: 11/16/1992
• Status: Expired due to Term

• Current Assignee: AGFA AG
• Original Assignee: Agta-Gevaerf AG
• Inventors: Lalvani, Prem, Jonas, Friedrich, Mues, Willem, Andries, Hartwig, Krafft, Werner
• Primary Examiner(s): Baxter, Janet C.
• Assistant Examiner(s): Huff, Mark F.
• Application Number:
  US08/290,597
• Time in Patent Office: 372 Days
• Field of Search: 430/140, 430/496, 430/501, 430/527, 430/529, 430/533, 428/694 B, 428/694 SL, 428/694 BP, 428/694 BS
• US Class Current: 430/529
• CPC Class Codes: C08G 61/126 with a five-membered ring containing one sulfur atom in the ring
• CPC Class Codes: G03C 1/89 Macromolecular substances therefor
• CPC Class Codes: G03C 11/02 Marking or applying text
• CPC Class Codes: G11B 5/633 of cinematographic films or slides with integral magnetic track
• CPC Class Codes: G11B 5/72 Protective coatings, e.g. anti-static or antifriction

Abstract

A photographic material comprising a transparent film support having on one side at least one light-sensitive layer and on the other side a transparent magnetic layer and an antistatic layer of a polythiophene arranged above or below said transparent magnetic layer shows transparency and good mechanical and antistatic properties.

Claims

1. Photographic material comprising a transparent film support having on one side at least one light-sensitive layer and on the other side a transparent magnetic layer, characterised in that an antistatic layer of a polythiophene is arranged on the same side of the transparent film support as said transparent magnetic layer below or above said transparent magnetic layer.

2. Photographic material according to claim 1, characterised in that the polythiophene is polyethylenedioxythiophene.

3. Photographic material according to claim 1, characterised in that the polythiophene contains anions of polymeric carboxylic acids or of polymeric sulphonic acids.

4. Photographic material according to claim 1, characterised in that the magnetic layer contains γ

-Fe₂ O₃ as magnetic pigment.

5. Photographic material according to claim 4, characterised in that the γ

-Fe₂ O₃ is doped or surface-treated with cobalt.

6. Photographic material according to claim 3, characterised in that the magnetic layer Contains a magnetic pigment in a quantity of from 30 to 100 mg/m² and the antistatic layer contains the polythiophene in a quantity of from 1 to 20 mg/m² calculated without the anions of polymeric carboxylic or sulphonic acids.

7. Photographic material according to claim 1, characterised in that the film support consists of from 90 to 98 mol-% of polyethylene terephthalate, from 2 to 10 mol-% of polyethylene sulphoisophthalate and optionally other polyesters.

8. Photographic material according to claim 1, characterized in that the antistatic layer is arranged underneath the magnetic layer.

9. Photographic material according to claim 1, wherein said magnetic layer has a dry layer thickness of from 0.5 to 0.2 μ

m and said antistatic layer has a dry thickness of from 0.05 to 0.2 μ

m.

10. Photographic material according to claim 9, wherein the antistatic layer is applied underneath the magnetic layer.

11. Photographic material according to claim 1, wherein the transparent film support is of polyethylene naphthalate.