Device with protective cover
View Patent ↗Provided herein are high flow and ductile thermoplastic resin compositions for the formation of thin wall articles and articles with desirable impact strengths. These compositions are useful in the manufacture of various shaped, formed and/or molded articles.
1. A device comprising:
a touch screen display having functional icons; and
a protective cover comprising a sheet molded from a thermoplastic composition, the sheet having a thickness of 0.5 mm or less and a surface area of at least 150 mm 2 , the thermoplastic composition comprising
(a) a poly(aliphatic ester)-polycarbonate copolymer comprising soft block ester units and carbonate units;
(b) a heat stabilizer; and
(c) an epoxy resin,
wherein the thermoplastic composition has a melt flow rate ranging from 40 g/10 minutes to 150 g/10 minutes, measured according to ASTM D1238 at 300° C. and 1.2 kilogram-force;
wherein the protective cover is placed over the touch screen display.
2. The device of claim 1 , wherein the sheet has a thickness of 0.3 mm or less.
3. The device of claim 1 , wherein the sheet has a thickness of 0.25 mm or less.
4. The device of claim 1 , wherein the protective cover has a light transmission of greater than or equal to 89% and less than 1% haze at 3.2 mm thickness according to ASTM D 1003.
5. The device of claim 1 , wherein the device is a smartphone, personal digital assistant, tablet computer, or hand-held video game device.
6. The device of claim 1 , further comprising a circuit board comprising touch sensors and illuminating elements to illuminate the function icons on the touch screen display, the touch sensors and illuminating elements being respectively mounted at positions on the circuit board corresponding to the plurality of function icons.
7. The device of claim 6 , further comprising a cover frame, mounted from the touch screen display and the circuit board, for supporting the touch screen display, the circuit board connected to the cover frame, wherein the cover frame comprises a plurality of light guide hollows for guiding light from the illuminating elements to the function icons, the light guide hollows having a funnel shape in which a diameter of each of the light guide hollows increases away from the illuminating elements.
8. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein an ASTM part molded from the thermoplastic composition exhibits 100% ductility at 23° C.
9. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the thermoplastic composition exhibits a melt flow rate of below 150 g/10 minutes at 300° C. under a load of 1.2 kg according to ASTM D 1238.
10. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the thermoplastic composition exhibits a melt flow rate of 100 g/10 minutes at 300° C. under a load of 1.2 kg according to ASTM D 1238.
11. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the thermoplastic composition exhibits a melt flow rate of 40 g/10 min at 300° C. under a load of 1.2 kg according to ASTM D 1238.
12. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the thermoplastic composition exhibits a melt flow rate of 55 g/10 min at 300° C. under a load of 1.2 kg according to ASTM D 1238.
13. The device of claim 12 , wherein the thermoplastic composition further comprises a low molecular weight bisphenol-A polycarbonate having a molecular weight of 17,000 g/mol, as measured by gel permeation chromatography (GPC) using bisphenol-A polycarbonate standards.
14. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the soft block ester units of the poly(aliphatic ester)-polycarbonate are derived from an alpha, omega C 6 - 20 aliphatic dicarboxylic acid or a derivative thereof.
15. The device of claim 14 , wherein the alpha, omega C 6 - 20 aliphatic dicarboxylic acid is an alpha, omega C 10 dicarboxylic acid.
16. The device of claim 15 , wherein the C 10 dicarboxylic acid is sebacic acid.
17. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the poly(aliphatic ester)-polycarbonate copolymer comprising soft block ester units and carbonate units has the following formula:
wherein n is from 1 to 6; and m is from 25 to 60.
18. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the poly(aliphatic ester)-polycarbonate copolymer contains 6.0 mol % sebacic acid.
19. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the heat stabilizer is:
tris(2,4-di-t-butylphenyl)phosphite;
bis(2,4-dicumylphenyl)pentaerythritol diphosphite; or a combination thereof.
20. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the epoxy resin is a hydrolytic stabilizer.
21. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the epoxy resin has multiple epoxy groups.
22. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the epoxy resin is Joncryl ADR-4368CS.
23. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the thermoplastic composition further comprises a mold release agent.
24. The device of claim 23 , wherein the mold release agent is pentaerythritol tetrastearate (PETS), a phthalic acid ester, or a poly-alpha-olefin.
25. The device of claim 24 , wherein the mold release agent is pentaerythritol tetrastearate (PETS).
26. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein a 3.2 mm thick plaque molded from the thermoplastic composition, molded at 550° F. melt temperature and 10 minutes dwell time, exhibits a Yellowing Index (YI) value of less than 2.00.
27. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein a 3.2 mm thick plaque molded from the thermoplastic composition, molded at 550° F. melt temperature and 10 minutes dwell time, exhibits a Yellowing Index (YI) percent increase of 6% or less compared to a 3.2 mm thick plaque molded from the thermoplastic composition at 550° F. melt temperature and 30 seconds dwell time.
28. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein a 3.2 mm thick plaque molded from the thermoplastic composition exhibits a 96% or greater molecular weight retention after exposure to 85° C. at 85% relative humidity (RH) after 4 weeks.
29. The device of any one of claim 1 , 2 - 4 , or 5 - 7 , wherein the thermoplastic composition is produced by a process comprising use of a redistribution catalyst that is 45% tetra-n-butyl phosphonium hydroxide solution in water.