Laser-writable polymer composition

• US 20020077380A1
• Filed: 12/26/2001
• Published: 06/20/2002
• Est. Priority Date: 06/30/1999
• Status: Active Grant

• Current Assignee: DSM IP Assets BV (DSM-Firmenich AG)
• Original Assignee: DSM IP Assets BV (DSM-Firmenich AG)
• Inventors: Wessels, Esther, Higler, Johannes F.
• Granted Patent: US 6,903,153 B2
• Time in Patent Office: Days
• US Class Current: 522/2
• CPC Class Codes: C08K 3/2279 of antimony

Abstract

The invention relates to a polymer composition containing a polymer and, as an additive for making a dark laser marking, at least 0.1 wt. % antimony trioxide having an average particle size above 0.5 micrometer. The invention also relates to articles wholly or partly made of the polymer composition and to a process for applying a dark laser mark onto a light background of such article. The polymer composition according to the invention can be marked with laser light of wavelength 1064 nm.

Claims

1. Polymer composition containing a polymer and, as an additive for making a dark laser marking on a light background, at least 0.1 wt. %, relative to the total weight of the polymer composition, of antimony trioxide, characterized in that the antimony trioxide has an average particle size above 0.5 micrometer, and the composition also contains a nacreous pigment.

2. Polymer composition according to claim 1, characterized in that the antimony trioxide has a particle size between 1 and 8 micrometer.

3. Polymer composition according to claim 2, characterized in that the amount is between 0.5 and 5 wt. %.

4. Polymer composition according to any one of claims 1-3, characterized in that the polymer composition is essentially halogen free.

5. Polymer composition according to any one of claims 1-4, comprising between 2 and 5 wt. % antimony trioxide with an average particle size of at least 1.5 micrometer.

7. Polymer composition according to any one of claims 1-6, characterized in that it contains between 0.5 and 3 wt. % antimony trioxide and between 0.1 and 3 wt. % nacreous pigment.

8. Polymer composition according to any one of claims 1-7, characterized in that the weight ratio of the nacreous pigment and the antimony trioxide lies between 1:

0.5 and 1;

50.

9. Polymer composition according to any one of claims 1-8, characterized in that the polymer composition is essentially halogen free and contains a halogen-free flame retardant.

10. Polymer composition according to claim 9, characterized in that it contains melamine cyanurate as the halogen-free flame retardant.

11. Article, wholly or partly made of the polymer composition according to any one of claims 1-10.

13. Process according to claim 12, wherein the antimony trioxide has a particle size between 1 and 8 micrometer.

18. Process according to claim 17, wherein the polymer composition contains melamine cyanurate as the halogen-free flame retardant.

19. Process for applying a dark laser marking onto a light background, in which an article consisting, at least at the place where the marking is applied, of a polymer composition according to any one of claims 1-10 is irradiated with laser light in the pattern of the marking.

6. Polymer composition containing a polymer, at least 0.5 wt. % antimony trioxide and at least 0.1 wt. % of a nacreous pigment.

12. Process for applying a dark laser marking onto a light background, in which an article consisting, at least at the place where the marking is applied, of a polymer composition containing a polymer and at least 0.1 wt. %, relative to the total weight of the polymer composition, of antimony trioxide having an average particle size above 0.5 micrometer, is irradiated with laser light in the pattern of the marking.

14. Process according to any one of claims 12-13, wherein the polymer composition contains between 0.5 and 5 wt. % of antimony trioxide.

15. Process according to any one of claims 12-14, wherein the polymer composition is essentially halogen free.

16. Process according to any one of claims 12-15, wherein the polymer composition contains between 2 and 5 wt. % antimony trioxide with an average particle size of at least 1.5 micrometer.

17. Process according to any one of claims 12-16, wherein the polymer composition is essentially halogen free and contains a halogen-free flame retardant.

20. Process according to any one of claims 12-19, characterized in that the article is irradiated with laser light with a wavelength of 1064 nm.

21. Process according to any one of claims 12-20, characterized in that the article is irradiated with laser light from a diode-pumped laser.

22. Process according to any one of claims 12-21, characterized in that the article is radiated with laser light from an Nd:

YAG laser.