Plastic composition comprising a polycarbonate made from low sulfur bisphenol A, and articles made therefrom

• US 9,771,452 B2
• Filed: 08/29/2016
• Issued: 09/26/2017
• Est. Priority Date: 02/29/2012
• Status: Active Grant

• Current Assignee: SHPP Global Technologies BV (Government of Saudi Arabia)
• Original Assignee: SABIC Global Technologies BV (Government of Saudi Arabia)
• Inventors: de Brouwer, Johannes, Hein, Christopher Luke, Evans, Thomas L., Belfadhel, Hatem Abdallah, Vieveen, Marcel, Wold, Christian, Brander, Eric
• Primary Examiner(s): Williams, Joseph L
• Application Number:
  US15/250,244
• Publication Number:
  US 20160369049A1
• Time in Patent Office: 393 Days
• CPC Class Codes: C07C 29/78 by condensation or crystallisation
• CPC Class Codes: C07C 37/20 using aldehydes or ketones
• CPC Class Codes: C07C 37/84 by crystallisation
• CPC Class Codes: C07C 37/86 by treatment giving rise to a chemical modification chemisorption C07C37/82
• CPC Class Codes: C07C 39/16 Bis-(hydroxyphenyl) alkanes; Tris-(hydroxyphenyl)alkanes
• CPC Class Codes: C08G 64/045 containing aliphatic unsaturation
• CPC Class Codes: C08G 64/307 and phenols
• CPC Class Codes: C08K 2201/001 Conductive additives
• CPC Class Codes: C08K 3/013 Fillers, pigments or reinforcing additives
• CPC Class Codes: C08K 9/06 with silicon-containing compounds
• CPC Class Codes: C08L 69/00 Compositions of polycarbonates; Compositions of derivatives of polycarbonates
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• CPC Class Codes: C09K 11/574 with zinc or cadmium
• CPC Class Codes: C09K 11/77 containing rare earth metals
• CPC Class Codes: C09K 11/7734 Aluminates
• CPC Class Codes: F21V 1/17 the material comprising photoluminescent substances
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 3/062 the material being plastics
• CPC Class Codes: F21V 9/30 Elements containing photoluminescent material distinct from or spaced from the light source shades F21V1/17; globes, bowls or cover glasses F21V3/08, F21V3/12; refractors F21V5/10; reflectors F21V7/26, F21V7/30; elements with provision for controlling the spectral properties or intensity F21V9/40
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 1/04 : made of organic materials, e.g. plastics G02B1/08 takes precedence
• CPC Class Codes: H01L 33/501 : characterised by the materials, e.g. binder
• CPC Class Codes: H01L 33/502 : Wavelength conversion materials
• CPC Class Codes: H01L 33/56 : Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H05B 33/12 : Light sources with substantially two-dimensional radiating surfaces

Abstract

In one embodiment, a light emitting device includes a lighting element located in a housing, wherein the housing is formed from a plastic composition including, for example, a polycarbonate formed from reacting, in the presence of a transesterification catalyst, a diaryl carbonate ester and a bisphenol A, wherein the bisphenol A has a sulfur concentration of 1 ppm to 15 ppm, based upon a weight of the bisphenol A; and a conversion material wherein the conversion material includes an inorganic material that converts radiation of a certain wavelength and re-emits of a different wavelength; wherein after the conversion material has been exposed to an excitation source, the conversion material has a luminescence lifetime of less than 10⁻⁴ seconds when the excitation source is removed.

Claims

1. A light emitting device, comprising:

a lighting element located in a housing, wherein the housing is formed from a plastic composition comprising;

a polycarbonate formed from reacting, in the presence of a transesterification catalyst, a diaryl carbonate ester and a bisphenol A, wherein the bisphenol A has a sulfur concentration of 1 ppm to 15 ppm, based upon a weight of the bisphenol A; and

a conversion material wherein the conversion material comprises an inorganic material that converts radiation of a certain wavelength and re-emits of a different wavelength;

wherein after the conversion material has been exposed to an excitation source, the conversion material has a luminescence lifetime of less than 10<sup>−

4</sup> seconds when the excitation source is removed.

2. The device of claim 1, wherein the lighting element is a radiation source, and wherein the housing is an emitting portion that is in optical communication with the radiation source.

3. The device of claim 2,

wherein the radiation source is configured to emit radiation having a first wavelength range;

wherein the conversion material is configured to absorb at least a portion of the first wavelength range radiation and emit radiation having a second wavelength range;

wherein the housing is configured such that at least the first wavelength range radiation passes though the housing; and

wherein after the conversion material has been exposed to an excitation source, the conversion material has a luminescence lifetime of less than 10<sup>−

4</sup> seconds when the excitation source is removed.

4. The device of claim 1, wherein the plastic composition further comprises greater than 0 to 1 pbw particles, based upon 100 pbw of polycarbonate, wherein the particles are selected from at least one of the following scattering particles, interference particles, and color absorbing particles.

5. The device of claim 1, wherein the conversion material comprises a luminescent material having the formula:

(A³)₂SiO₄;

Eu²⁺D¹

wherein A³ is a divalent metal selected from at least one of the following Sr, Ca, Ba, Mg, Zn, Cd, and combinations comprising at least one of the foregoing; and

D¹ is a dopant selected from at least one of the following F, Cl, Br, I, P, S and N and combinations comprising at least one of the foregoing.

6. The device of claim 1, wherein the conversion material comprises a luminescent material having formula:

(YA⁵)₃(AlB¹)₅(OD³)₁₂;

Ce³⁺

where A⁵ is a trivalent metal selected from at least one of the following Gd, Tb, La, Sm, luminescence, or a divalent metal ion selected from Sr, Ca, Ba, Mg, Zn and Cd, and combinations comprising at least one of the foregoing;

B¹ is selected from at least one of the following Si, B, P, and Ga, and combinations comprising at least one of the foregoing; and

D³ is a dopant selected from F, Cl, Br, I, P, S, and N, and combinations comprising at least one of the foregoing.

7. The device of claim 1, wherein the conversion material comprises an orange-red silicate-based conversion material having formula:

(SrM1)₃Si(OD⁴)₅;

Eu

wherein M1 is selected from at least one of the following Ba, Ca, Mg, Zn, and combinations comprising at least one of the foregoing; and

D⁴ is selected from F, Cl, S, N, and combinations comprising at least one of the foregoing.

8. The device of claim 1, wherein the conversion material comprises an Eu²⁺ and/or Dy³⁺ doped conversion material having formula:

M₃MgSi₂O₈

wherein M is selected from at least one of the following Ca, Sr, Ba, and combinations comprising at least one of the foregoing.

9. The device of claim 1, wherein the conversion material comprises a rare earth doped a red silicon nitride based conversion material having a formula:

(SrM2)₂Si₅N₈

wherein M2 is selected from at least one of the following Sr, Ca, Mg, Zn, and combinations comprising at least one of the foregoing.

10. The device of claim 1, wherein the conversion material comprises a rare earth doped a red sulfate based conversion material having formula:

(SrM3)S

wherein M3 is selected from at least one of the following Ca, Ba, Mg, and combinations comprising at least one of the foregoing.

11. The device of claim 1, wherein the conversion material is a green sulfate based conversion material having formula:

(SrM3)(GaM4)₂S₄;

Eu

wherein M3 is selected from at least one of the following Ca, Ba, Mg, and combinations comprising at least one of the foregoing; and

M4 is selected from at least one of the following Al and In, and combinations comprising at least one of the foregoing.

12. The device of claim 1, wherein the conversion material is selected from at least one of the following:

a strontium silicate yellow conversion material;

yttrium aluminum garnet doped with rare earth element;

terbium aluminum garnet doped with a rare earth element;

silicate conversion materials;

nitride conversion materials;

nitrido silicates;

nitride orthosilicate;

oxonitridoaluminosilicates; and

combinations comprising at least one of the foregoing.

13. The device of claim 1, wherein the conversion material is a selected from at least one of the following:

combinations of yellow conversion material with a red conversion material;

combinations of green and red conversion material;

a semiconductor nanocrystals of cadmium sulfide mixed with manganese; and

combinations comprising at least one of the foregoing.

14. The device of claim 1, wherein the conversion material comprises a silicone oil coating.

15. The device of claim 14, wherein the conversion material is coated with 0.05 wt % to 20 wt % silicone oil based upon the weight of the conversion material and silicone oil.

16. The device of claim 14, wherein the silicone oil is selected from at least one of the following hydrogen-alkyl siloxane oil;

polydialkyl siloxance oil;

polydimethyl siloxane codiphenyl siloxane, dihydroxy terminated, and combinations comprising at least one of the foregoing.

17. The device of claim 1, wherein the conversion material comprises an amorphous silica coating.

18. The device according to claim 1, wherein the device is at least one of the following:

a lamp, illumination device, lighting device for applications in the interior and exterior area, vehicle lighting, internal lighting of residential and work rooms, backlight units of LCD screens, and accent lighting.

19. The device according to claim 1, wherein the device is a backlight unit of a LCD screen.

20. A plastic molded device having a transparency of greater than or equal to 30% measured according to ASTM D1003-00, Procedure B, illuminant C, on a spectrophotometer, and at a thickness of 1.04 mm, wherein the article is formed from the plastic composition comprising:

a polycarbonate formed from reacting, in the presence of a transesterification catalyst, a diaryl carbonate ester and a bisphenol A, wherein the bisphenol A has a sulfur concentration of 1 ppm to 15 ppm, based upon a weight of the bisphenol A; and

a conversion material wherein the conversion material comprises an inorganic material that converts radiation of a certain wavelength and re-emits of a different wavelength;

wherein after the conversion material has been exposed to an excitation source, the conversion material has a luminescence lifetime of less than 10<sup>−

4</sup> seconds when the excitation source is removed.