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CN-116847993-B - Recording material for thermal sublimation printing with better transmission characteristics

CN116847993BCN 116847993 BCN116847993 BCN 116847993BCN-116847993-B

Abstract

The invention relates to a recording material for thermal sublimation printing, comprising a base paper (1) having a front side and a back side, at least one synthetic resin layer (4) located at least at the back side of the base paper (1), a dye receiving layer (2) arranged at the front side of the base paper (1), at least one plastic film (3) arranged between the base paper (1) and the dye receiving layer (2), and optionally a barrier layer arranged between the plastic film (3) and the dye receiving layer (2), wherein the synthetic resin layer (4) has an E-modulus of at least 0.8GPa.

Inventors

  • Christopher Kozlovsky
  • MICHAEL CROWTHER
  • Andreas Dickman
  • BERNER HANS-ULRICH

Assignees

  • 古楼特西诺采纸业有限两合公司

Dates

Publication Date
20260512
Application Date
20220204
Priority Date
20210204

Claims (15)

  1. 1. Recording material for thermal sublimation printing comprising A. base paper with front and back (1) B. At least one synthetic resin layer (4) located on at least the back side of the base paper C. Dye receiving layer (2) on the front side of the base paper D. at least one plastic film (3) arranged between the base paper and the dye-receiving layer, and E. a barrier layer (5) optionally arranged between the plastic film (3) and the dye-receiving layer (2), Characterized in that the synthetic resin layer (4) has an E modulus of at least 0.8 GPa, wherein the synthetic resin layer (4) contains at least 5% by weight of one of 4-methylpentene-1 homo-and copolymer polymers, 55 to 85% by weight of HD-PE and 5 to 25% by weight of LD-PE or the synthetic resin layer (4) has a pigment content of at least 5% by weight, 75 to 85% by weight of HD-PE and 0 to 15% by weight of LD-PE, respectively, relative to the dry weight of the synthetic resin layer.
  2. 2. The recording material according to claim 1, wherein the synthetic resin layer (4) has an E modulus of at least 0.90 GPa.
  3. 3. The recording material according to claim 2, wherein the synthetic resin layer (4) has an E modulus of at least 0.95 GPa.
  4. 4. Recording material according to any one of the preceding claims, characterized in that the synthetic resin layer (4) has a pigment content of at least 10% by weight relative to the dry weight of the synthetic resin layer.
  5. 5. The recording material of claim 4, wherein the pigment is selected from the group consisting of calcium carbonate, aluminum oxide, aluminum silicate, and mixtures thereof.
  6. 6. Recording material according to claim 1, characterized in that the plastic film (3) is a biaxially oriented plastic film.
  7. 7. Recording material according to claim 6, characterized in that the plastic film (3) is a biaxially oriented polypropylene film.
  8. 8. Recording material according to claim 1, characterized in that the plastic film (3) comprises a barrier layer (5).
  9. 9. Recording material according to claim 8, characterized in that as the barrier layer (5) a mixture of a water-dispersible polymer binder and gelatin is used.
  10. 10. Recording material according to claim 9, characterized in that the water-dispersible polymeric binder in the barrier layer (5) is a polyester-polyurethane copolymer.
  11. 11. The recording material according to claim 1, wherein the dye-receiving layer (2) contains an optical brightening agent and a polar binder.
  12. 12. The recording material according to claim 11, characterized in that the polar binder in the dye-receiving layer (2) contains polyvinyl alcohol modified with carbonyl groups or carboxyl groups.
  13. 13. The recording material according to claim 11 or 12, characterized in that the proportion of polar binder in the dye-receiving layer (2) is 5 to 20% by weight.
  14. 14. Recording material according to claim 1, characterized in that an adhesive layer (6) is additionally applied on the front side of the base paper (1), said adhesive layer being arranged between the base paper (1) and the plastic film (3).
  15. 15. Recording material according to claim 14, characterized in that the adhesive layer (6) consists of LD-PE.

Description

Recording material for thermal sublimation printing with better transmission characteristics Technical Field The present invention relates to a recording material for thermal sublimation printing. Background Thermal sublimation printing is used to reproduce digitally generated images in the form of printed images, the image quality of which corresponds to the level of silver salt photographs. The digital image is subjected to dot processing with respect to the basic colors of cyan, magenta, yellow, and black, and converted into corresponding electric signals, which are then locally converted into heat by a thermal head in the printer. Dye is sublimated from a donor layer of a ribbon or patch in contact with the recording material to be printed by local thermal influence and diffuses to a dye receiving layer of the recording material. Initially, dye sublimation printing was considered to be the direct conversion of a dye from a solid state to a gaseous state, i.e. sublimation, by thermal effects. However, it has been found that, later on, during the thermal sublimation printing process, the dye liquefies to some extent, so that it is more appropriate to describe this process by the diffusion effect (so-called dye diffusion thermal transfer; D2T 2). The amount of dye transferred to the recording material varies depending on the thermal energy delivered to the pixels. In order to obtain a photo-quality image, a recording material for thermal sublimation printing must have a good surface, low thermal conductivity, high heat resistance, high compressibility, and good dimensional stability. In addition, the recording material for thermal sublimation printing must also have good storage properties after printing to prevent migration of the dye through the carrier over time, resulting in degradation of image quality. The compressibility of the recording material is important to ensure good contact between the printer thermal head and the recording material. During printing, accurate positioning of the recording material relative to the printhead is important because only one of the four primary colors (cyan, magenta, yellow, and black) can be applied simultaneously during each printing. Thus, the printed image must be created by applying the dye in four consecutive passes (a so-called multi pass process). Since the same color pixels must be precisely controlled up to four times at the same print location to produce the desired hue, variations in the position of the recording material relative to the printhead during colorant application can result in reduced image quality. For example, such a positional change (so-called offset) may be caused by difficulty in conveyance of the recording material in the printer. The transport rollers used in printers developed specifically for thermal sublimation printing, such as Mitsubishi WXL-185 2017, DNP DS-621, or Citizen CX, have surface roughness with needle-like ridges, which can ensure good connection with the recording material. However, in the recording materials which are common at present, friction is generated when the recording material is transported in the printer due to the characteristics of the contact surface of the recording material with the printer transport roller, and thus the optimal positioning of the recording material with respect to the print head cannot be ensured. In the sequential printing process, an offset is generated between the already applied print image and the print image applied in the subsequent printing process, thereby affecting the quality of the print image. Recording materials for thermal sublimation printing have been fully described in the prior art. They consist essentially of a support material, a dye-receiving layer and possibly further functional layers. For example, uncoated paper or coated paper can be used as the carrier material, wherein synthetic resin-coated paper, in particular polyolefin-coated paper, or paper provided with a multilayer plastic film is particularly suitable. Such carrier materials are described, for example, in EP 3 028 866A 1. The dye-receiving layer contains primarily a resin that has an affinity for the dye in the donor layer of the ribbon or sheet. For example, an ester compound-containing plastic such as a polyester resin, a polyacrylate resin, a polycarbonate resin, a polyvinyl acetate resin, a styrene acrylate resin, or an amide compound-containing plastic such as a polyamide resin or polyvinyl chloride, and a mixture of the above plastics may be used. The use of copolymers containing as the main component at least one of the abovementioned plastics, such as vinyl chloride/vinyl acetate copolymers, is also known in the prior art. As a further functional layer, for example, a so-called anti-curl layer is used for preventing the recording material from curling after passing through the thermal printer. For example, a plastic film clad or laminated on the back of the recording material is very suita