Thermal transfer sheet

Patent metadata

Field	Value
Publication number	US-12122176-B2
Application number	US-202017309974-A
Country	US
Kind code	B2
Filing date	Jan 9, 2020
Priority date	Jan 24, 2019
Publication date	Oct 22, 2024
Grant date	Oct 22, 2024

Abstract

Provided is a thermal transfer sheet that can form a good image on both a transfer object made of a polyethylene terephthalate and a transfer object made of a polypropylene, as well as can form an image with high alcohol resistance. The thermal transfer sheet of the present invention includes a substrate, and a transfer layer including a colored layer and an adhesive layer, in which the adhesive layer has a phase-separated structure formed by a polyester and a polyolefin that are incompatible with each other, and in which the percentage of the region formed by one of the polyester and the polyolefin to the total area (100%) of the adhesive layer is 55% or more and 85% or less.

First claim

The invention claimed is:

1. A thermal transfer sheet, comprising:
a substrate; and
a transfer layer comprising a colored layer and an adhesive layer,
wherein the adhesive layer has a phase-separated structure formed by a polyester and a polyolefin that are incompatible with each other,
wherein a percentage of a region formed by one of the polyester and the polyolefin to a total area (100%) of the adhesive layer is 55% or more and 85% or less,
wherein the polyolefin is a chlorinated polyolefin,
wherein the transfer layer further comprises a peeling layer located under the colored layer,
wherein the peeling layer contains polyethylene glycol having a number average molecular weight in a range of 8,000 to 23,000, and
wherein a content of the polyester in the adhesive layer is in a range of 61% by mass to 87% by mass.

2. The thermal transfer sheet according to claim 1 , wherein the percentage of the region formed by the polyester to the total area (100%) of the adhesive layer is in a range of 55% to 85%.

3. The thermal transfer sheet according to claim 1 , wherein the chlorinated polyolefin is an acid-modified chlorinated polyolefin.

4. The thermal transfer sheet according to claim 1 , wherein the chlorinated polyolefin has a chlorination rate in a range of 10% to 55%.

5. The thermal transfer sheet according to claim 1 , wherein the adhesive layer has a content of the polyolefin in a range of 13% by mass to 40% by mass.

6. The thermal transfer sheet according to claim 1 , wherein the adhesive layer is formed with an adhesive layer-forming coating liquid containing toluene and methyl ethyl ketone.

7. The thermal transfer sheet according to claim 1 , wherein the polyolefin has a number average molecular weight of less than 50,000.

8. The thermal transfer sheet according to claim 1 , wherein the adhesive layer has a thickness in a range of 0.05 μm to 0.5 μm.

9. The thermal transfer sheet according to claim 1 , wherein the peeling layer further contains a wax.

10. The thermal transfer sheet according to claim 1 , wherein the polyester has a number average molecular weight in a range of 3,000 to 50,000.

Assignees

• Dainippon Printing Co Ltd

Inventors

• Ikeda Megumi
• Ishida Tadahiro
• Imakura Yuzu
• NARUMI Yusuke

Classifications

• B41M5/443

  Silicon-containing polymers, e.g. silicones, siloxanes · CPC title

• B41M5/42 Primary

  Intermediate, {backcoat}, or covering layers {(B41M5/405 takes precedence; multilayer thermal transfer systems in general B41M5/38214)} · CPC title

• B41M2205/40

  Cover layers; Layers separated from substrate by imaging layer; Protective layers; Layers applied before imaging · CPC title

• B41M2205/38

  Intermediate layers; Layers between substrate and imaging layer · CPC title

• B41M2205/30

  Thermal donors, e.g. thermal ribbons · CPC title