Thermosensitive recording medium

• US 8,461,076 B2
• Filed: 03/07/2011
• Issued: 06/11/2013
• Est. Priority Date: 03/11/2010
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Okada, Shinji, Shimizu, Kenji
• Primary Examiner(s): Hess, Bruce H
• Application Number:
  US13/041,887
• Publication Number:
  US 20110224074A1
• Time in Patent Office: 827 Days
• Field of Search: None
• US Class Current: 503/226
• CPC Class Codes: B41M 2205/04 Direct thermal recording [DTR]
• CPC Class Codes: B41M 2205/36 Backcoats; Back layers
• CPC Class Codes: B41M 2205/40 Cover layers; Layers separated from substrate by imaging layer; Protective layers; Layers applied before imaging
• CPC Class Codes: B41M 5/42 Intermediate, backcoat, or covering layers B41M5/405 takes precedence; multilayer thermal transfer systems in general B41M5/38214
• CPC Class Codes: B41M 5/423 characterised by non-macromolecular compounds, e.g. waxes
• CPC Class Codes: B41M 5/44 characterised by the macromolecular compounds
• CPC Class Codes: B41M 5/443 Silicon-containing polymers, e.g. silicones, siloxanes

Abstract

To provide a thermosensitive recording medium, containing: a support; a thermosensitive recording layer; and a surface layer, where the thermosensitive recording layer and the surface layer are provided over the support, wherein the thermosensitive recording layer contains a binding agent, a coloring agent, and a color developer, and wherein the surface layer contains polyester (meth)acrylate having at least three (meth)acryloyl groups, and an α-hydroxyketone-based polymerization initiator having a melting point of 80° C. or higher.

Claims

1. A thermosensitive recording medium, comprising:

a support;

a thermosensitive recording layer; and

a surface layer, where the thermosensitive recording layer and the surface layer are provided over the support,

wherein the thermosensitive recording layer contains a binding agent, a coloring agent, and a color developer, and

wherein the surface layer contains polyester (meth)acrylate having at least three (meth)acryloyl groups, and an α

-hydroxyketone-based polymerization initiator having a melting point of 80°

C. or higher.

2. The thermosensitive recording medium according to claim 1, wherein the surface layer further contains an acyl phosphinoxide-based polymerization initiator.

3. The thermosensitive recording medium according to claim 1, wherein the surface layer further contains filler, a lubricant, or both thereof.

4. The thermosensitive recording medium according to claim 1, wherein the surface layer further contains a polyorganosiloxane-polyether copolymer.

5. The thermosensitive recording medium according to claim 1, wherein the surface layer is formed by ultraviolet irradiation which is performed with an oxygen concentration of 0.1% to 1%, and ultraviolet irradiation intensity of 50 mJ/cm² to 200 mJ/cm².

6. The thermosensitive recording medium according to claim 1, further comprising an intermediate layer provided between the thermosensitive recording layer and the surface layer, wherein the intermediate layer contains a water-soluble resin, water-dispersible resin, or both thereof.

7. The thermosensitive recording medium according to claim 6, wherein the thermosensitive recording layer, the intermediate layer, or both thereof contain an ultraviolet absorber.

8. The thermosensitive recording medium according to claim 6, wherein at least one layer selected from the group consisting of the thermosensitive recording layer, the intermediate layer, and the surface layer contains a fluorescent dye.

9. The thermosensitive recording medium according to claim 1, further comprising a back layer provided on a surface of the support opposite to the surface thereof where the thermosensitive recording layer is provided, wherein the back layer contains a binder.

10. The thermosensitive recording medium according to claim 9, wherein the back layer further contains filler.

11. The thermosensitive recording medium according to claim 9, wherein the back layer further contains an antistatic agent.

12. The thermosensitive recording medium according to claim 9, wherein the back layer, the surface layer, or both thereof further contain an antistatic agent.

13. The thermosensitive recording medium according to claim 1, wherein the surface layer further contains fatty acid amide.