Patent ID: 8257988

Claim:
A method of making a light emitting diode (LED) having an optical element, comprising: providing a curable liquid polysiloxane/TiO 2 composite, comprising: (a) combining in an aprotic solvent: (i) D units having a formula R 1 (R 2 )Si(OR 6 ) 2 ; (ii) T units having a formula R 3 Si(OR 7 ) 3 ; (iii) optionally, M units having a formula R 4 3 SiOR 8 ; and, (iv) optionally, Q units having a formula Si(OR 9 ) 4 ; wherein each R 1 and R 3 is independently selected from a C 6-10 aryl group and a C 7-20 alkylaryl group; wherein each R 2 is a phenoxyphenyl group; wherein each R 4 is independently selected from a C 1-10 alkyl group, a C 7-10 arylalkyl group, a C 7-10 alkylaryl group and a C 6-10 aryl group; wherein each R 6 , R 7 , R 8 and R 9 is independently selected from a hydrogen atom, a C 1-10 alkyl group, a C 7-10 arylalkyl group, a C 7-10 alkylaryl group and a C 6-10 aryl group; and wherein each R 6 , R 7 , R 8 and R 9 is independently selected from a hydrogen atom, a C 1-10 alkyl group, a C 7-10 arylalkyl group, a C 7-10 alkylaryl group and a C 6-10 aryl group; (b) adding to the combination of (a) an acid in a miscible mixture of water and an alcohol to form a reaction mixture; (c) allowing the reaction mixture to react; (d) adding an organo-titanate in an aprotic solvent to the reacted reaction mixture of (c); (e) adding water to the product of (d); (f) heating the product of (e) and allowing it to react; and, (g) purifying the product of (f) to provide the curable liquid polysiloxane/TiO 2 composite; wherein the curable liquid polysiloxane/TiO 2 composite exhibits a refractive index of >1.61 to 1.7 and wherein the curable liquid polysiloxane/TiO 2 composite is a liquid at room temperature and atmospheric pressure; providing a semiconductor light emitting diode die having a face, wherein the semiconductor light emitting diode die emits light through the face; contacting the semiconductor light emitting diode die with the curable liquid polysiloxane/TiO 2 composite; and, curing the curable liquid polysiloxane/TiO 2 composite to form an optical element; wherein at least a portion of the optical element is adjacent to the face.