Polyethylene terephthalate moulding compositions having high reflectivity

• US 4,489,110 A
• Filed: 07/21/1983
• Issued: 12/18/1984
• Est. Priority Date: 01/15/1982
• Status: Expired due to Fees

• Current Assignee: Bayer AG
• Original Assignee: Bayer AG
• Inventors: Bier, Peter
• Primary Examiner(s): Marquis, Melvyn I.
• Application Number:
  US06/515,728
• Time in Patent Office: 516 Days
• Field of Search: 524/447, 524/605, 264/1.1, 264/1.9, 428/687, 106/288 B, 106/291, 427/250, 427/316
• US Class Current: 427/250
• CPC Class Codes: C08K 3/346 Clay
• CPC Class Codes: C08L 67/02 Polyesters derived from dicarboxylic acids and dihydroxy compounds C08L67/06 takes precedence
• CPC Class Codes: F21V 7/24 characterised by the material
• CPC Class Codes: F21V 7/28 characterised by coatings
• CPC Class Codes: Y10T 428/12993 Surface feature [e.g., rough, mirror]

Abstract

Polyethylene terephthalate moulding compositions which contain delaminated kaolin may be processed into highly-reflecting objects.

Claims

1. A process for preparing light reflectors comprising

(i) molding an article using a composition comprising

(I) from 30 to 85 parts by weight of polyethylene terephthalate having an intrinsic viscosity of at least 0.4 dl/g as measured by using a 0.5%, by weight solution in phenol/o-dichlorobenzene (weight ratio 60:

40) at 25°

C.;

(II) from 2 to 70 parts, by weight, of delaminated kaolin; and

(III) from 0 to 70 parts, by weight, of fillers other than delaminated kaolins and/or reinforcing agents and

(ii) metallizing at least a portion of said article.

2. The process of claim 1 wherein at least 90% by weight of said delaminated kaolin have particle thicknesses of from 0.02 to 0.2 microns.

3. The process of claim 1 wherein said delaminated kaolin is characterized in that its average particle thickness is less than 0.1 micron.

4. The process of claim 1 wherein said delaminated kaolin has an average particle thickness of from 0.06 to 0.09 microns.

5. The process of claim 1 wherein at least 90% by weight of said delaminated kaolin has a diameter of from 0.5 to 4.0 microns.

6. The process of claim 1 wherein said delaminated kaolin has an average particle diameter of from 1 to 2 microns.

7. The process of claim 1 wherein said reinforing agent is glass fibers.

8. The light reflector prepared by the process of claim 1.

9. A process for preparing light reflectors comprising

(i) molding an article from a composition comprising

(a) from 30 to 85 parts by weight, of polyethylene terephthalate having an intrinsic viscosity of at least 0.4 dl/g as measured using a 0.5% by weight solution in phenol/o-dichlorobenzene (weight ratio 60:

40) at 25°

C., and

(b) from 2 to 70 parts by weight of delaminated kaolin

(ii) priming at least a portion of said article and

(iii) metallizing said portion.

10. The process of claim 9 wherein said metallizing consists of applying aluminum by vapor deposition.

11. The process of claim 10 wherein said priming consists of polyurethane lacquering.