LASER-MARKABLE ARTICLE WITH CUSTOMIZED WATERMARKS AND PREPARATION METHOD THEREOF

• US 20200135059A1
• Filed: 05/30/2018
• Published: 04/30/2020
• Est. Priority Date: 06/05/2017
• Status: Abandoned Application

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Zhang, Jiazhi
• Application Number:
  US16/619,425
• Publication Number:
  US 20200135059A1
• Time in Patent Office: Days
• CPC Class Codes: B23K 26/362 Laser etching
• CPC Class Codes: C09J 201/02 characterised by the presence of specified groups , e.g. terminal or pendant functional groups
• CPC Class Codes: C09J 2203/334 as a label
• CPC Class Codes: C09J 2301/302 the adhesive being pressure-sensitive, i.e. tacky at temperatures inferior to 30°C
• CPC Class Codes: G09F 2003/0201 Label sheets intended to be introduced in a printer, e.g. laser printer
• CPC Class Codes: G09F 2003/0257 Multilayer
• CPC Class Codes: G09F 2003/0276 Safety features, e.g. colour, prominent part, logo
• CPC Class Codes: G09F 3/0291 Labels or tickets undergoing a change under particular conditions, e.g. heat, radiation, passage of time
• CPC Class Codes: G09F 3/0294 where the change is not permanent, e.g. labels only readable under a special light, temperature indicating labels and the like
• CPC Class Codes: G09F 3/10 by an adhesive layer

Abstract

The present disclosure provides a laser-markable article with customized watermarks and a preparation method thereof. The laser-markable article with customized watermarks comprises a surface layer (1) containing a first coloring agent, a bottom layer (2) containing a second coloring agent, an adhesive layer (3), and an optional release layer (4) arranged consecutively in a stack, and further comprises customized watermarks (5′,5″) arranged in the surface layer (1), wherein the customized watermarks (5′,5″) are comprised of a plurality of watermark units spaced apart from one another and regularly distributed in the surface layer (1), and each watermark unit is comprised of a laser-etched pattern with an etch depth of 2.5 to 25 micrometers. The laser-markable article with customized watermarks have good abrasive resistance, durability, and appearance effects.

Claims

1. A laser-markable article with customized watermarks, comprising a surface layer containing a first coloring agent, a bottom layer containing a second coloring agent, an adhesive layer, and an optional release layer arranged consecutively in a stack, wherein

the laser-markable article further comprises customized watermarks arranged in the surface layer, the customized watermarks are comprised of a plurality of watermark units spaced apart from one another and regularly distributed in the surface layer, and each watermark unit is comprised of a laser-etched pattern with an etch depth of 2.5 μ

m to 25 μ

m.

2. The laser-markable article with customized watermarks according to claim 1, wherein

a depth of the watermark units is less than a thickness of the surface layer, or

a depth of a portion of the pattern in the watermark units is greater than the thickness of the surface layer but not more than the total thickness of the surface layer and the bottom layer, and an area of the pattern with a depth greater than the thickness of the surface layer accounts for not more than 20% in each watermark unit.

4. The laser-markable article with customized watermarks according to claim 1, wherein

the pattern of the watermark units is comprised of dots and/or lines, with a spacing between the dots being from 0 μ

m to 1.5 mm.

5. The laser-markable article with customized watermarks according to claim 1, wherein

the first coloring agent and the second coloring agent are two contrasting coloring agents.

6. The laser-markable article with customized watermarks according to claim 4, wherein

the first coloring agent is a black coloring agent, and the second coloring agent is a white coloring agent.

7. The laser-markable article with customized watermarks according to claim 1, wherein

the surface layer has a thickness of 2 μ

m to 25 μ

m.

8. The laser-markable article with customized watermarks according to claim 1, wherein

the bottom layer has a thickness of 30 μ

m to 100 μ

m.

9. The laser-markable article with customized watermarks according to claim 1, wherein

the surface layer and the bottom layer are formed with resin compositions comprised of a first coloring agent and a second coloring agent respectively.

10. The laser-markable article with customized watermarks according to claim 8, wherein

the resin compositions further comprise polyvinyl butyral, a polyester resin, and a curing agent for film formation.

11. The laser-markable article with customized watermarks according to claim 1, wherein

the adhesive layer is a pressure-sensitive adhesive layer.

12. The laser-markable article with customized watermarks according to claim 1, wherein the article is used as a label having a vehicle identification code.

13. A method for preparing the laser-markable article with customized watermarks according to claim 1, the method comprising:

laser-etching the surface layer of the laser-markable article to form customized watermarks, an etch depth is from 2.5 μ

m to 25 μ

m.

14. A method according to claim 12, wherein before laser-etching the surface layer of the laser-markable article, the method further comprises the following steps:

forming a surface layer containing a first coloring agent on a carrier film;

forming a bottom layer containing a second coloring agent on the surface layer;

forming an adhesive layer optionally with a release layer on the bottom layer; and

stripping off the carrier film.

15. The method according to claim 13, wherein

the forming of a surface layer of the first coloring agent on the carrier film comprises:

dissolving a resin composition containing the first coloring agent, polyvinyl butyral, a polyester resin, and a curing agent for film formation into a solvent, followed by coating the solvent onto the carrier film.

16. The method according to claim 13, wherein

the forming of a bottom layer of the second coloring agent on the surface layer comprises:

dissolving a resin composition containing the second coloring agent, polyvinyl butyral, a polyester resin, and a curing agent for film formation into a solvent, followed by coating the solvent onto the surface layer.

17. The method according to claim 14, wherein

the coating method includes blade coating, slit coating, and screen roller coating.

18. The method according to claim 12, wherein

a laser source for the laser-etching is a CO₂, Nd-YAG, or UV laser source.