CURABLE SILICONE COMPOSITION, ENCAPSULANT AND OPTICAL SEMICONDUCTOR DEVICE

Abstract

A curable silicone composition is provided that is exhibits excellent wetting properties on glass substrates and that forms a cured product that has a smooth surface. The curable silicone composition comprises: (A-1) a resinous alkenyl group-containing organopolysiloxane in which aryl groups account for more than 30 mol % of all silicon atom-bonded functional groups; (A-2) a linear alkenyl group-containing organopolysiloxane in which aryl groups account for more than 30 mol % of all silicon atom-bonded functional groups; (B) a linear organopolysiloxane or a cerium-containing organopolysiloxane, in which aryl groups account for no more than 30 mol % of all silicon atom-bonded functional groups, contained in an amount of no more than 2% by mass based on the total mass of all organopolysiloxane components; (C) an organohydrogenpolysiloxane including at least 2 silicon atom-bonded hydrogen atoms per molecule, that is different from component (B); and (D) a catalyst for hydrosilylation reaction.

Claims

1. A curable silicone composition comprising: (A-1) a resinous alkenyl group-containing organopolysiloxane in which aryl groups account for more than 30 mol % of all silicon atom-bonded functional groups; (A-2) a linear alkenyl group-containing organopolysiloxane in which aryl groups account for more than 30 mol % of all silicon atom-bonded functional groups; (B) a linear organopolysiloxane or a cerium-containing organopolysiloxane, in which aryl groups account for no more than 30 mol % of all silicon atom-bonded functional groups, contained in an amount of no more than 2% by mass based on the total mass of all organopolysiloxane components; (C) an organohydrogenpolysiloxane including at least 2 silicon atom-bonded hydrogen atoms per molecule, that is different from component (B); and (D) a catalyst for hydrosilylation reaction.

2. The curable silicone composition according to claim 1, wherein the content of organopolysiloxane components (A-1) and (A-2) is 30 to 90% by mass based on the total mass of all organopolysiloxane components in the composition.

3. The curable silicone composition according to claim 1, wherein organopolysiloxane component (B) has a number-average molecular weight of 500 or more.

4. The curable silicone composition according to claim 1, wherein the content of organopolysiloxane component (B) is 1.5% by mass or less based on the total mass of all organopolysiloxane components.

5. The curable silicone composition according to claim 1, wherein organohydrogenpolysiloxane component (C) contains silicon atom-bonded aryl groups, and the aryl groups account for 5 to 50 mol % of all silicon atom-bonded functional groups of component (C).

6. The curable silicone composition according to claim 1, wherein the content of organohydrogenpolysiloxane component (C) is 5% by mass or more based on the total mass of all organopolysiloxane components.

7. An encapsulant, comprising the curable silicone composition according to claim 1.

8. An optical semiconductor device, equipped with the encapsulant according to claim 7.

9. The curable silicone composition according to claim 2, wherein organopolysiloxane component (B) has a number-average molecular weight of 500 or more.

10. The curable silicone composition according to claim 2, wherein the content of organopolysiloxane component (B) is 1.5% by mass or less based on the total mass of all organopolysiloxane components.

11. The curable silicone composition according to claim 3, wherein the content of organopolysiloxane component (B) is 1.5% by mass or less based on the total mass of all organopolysiloxane components.

12. The curable silicone composition according to claim 9, wherein the content of organopolysiloxane component (B) is 1.5% by mass or less based on the total mass of all organopolysiloxane components.

13. The curable silicone composition according to claim 2, wherein organohydrogenpolysiloxane component (C) contains silicon atom-bonded aryl groups, and the aryl groups account for 5 to 50 mol % of all silicon atom-bonded functional groups of component (C).

14. The curable silicone composition according to claim 3, wherein organohydrogenpolysiloxane component (C) contains silicon atom-bonded aryl groups, and the aryl groups account for 5 to 50 mol % of all silicon atom-bonded functional groups of component (C).

15. The curable silicone composition according to claim 4, wherein organohydrogenpolysiloxane component (C) contains silicon atom-bonded aryl groups, and the aryl groups account for 5 to 50 mol % of all silicon atom-bonded functional groups of component (C).

16. The curable silicone composition according to claim 2, wherein the content of organohydrogenpolysiloxane component (C) is 5% by mass or more based on the total mass of all organopolysiloxane components.

17. The curable silicone composition according to claim 3, wherein the content of organohydrogenpolysiloxane component (C) is 5% by mass or more based on the total mass of all organopolysiloxane components.

18. The curable silicone composition according to claim 4, wherein the content of organohydrogenpolysiloxane component (C) is 5% by mass or more based on the total mass of all organopolysiloxane components.

19. The curable silicone composition according to claim 5, wherein the content of organohydrogenpolysiloxane component (C) is 5% by mass or more based on the total mass of all organopolysiloxane components.

Description

EXAMPLES

[0147] The UV curable silicone composition of the present disclosure is described in greater detail by means of the following examples and comparative examples.

[0148] The starting material components shown below were used in the following examples and comparative examples. Below, Me denotes methyl groups, Vi denotes vinyl groups, Ph denotes phenyl groups, and Ep denotes 3-glycidoxypropyl groups.

[0149] Component a-1: Resinous alkenyl group-containing organopolysiloxane represented by average unit formula (ViMe.sub.2SiO.sub.1/2).sub.25(PhSiO.sub.3/2).sub.75; phenyl groups account for 66.7 mol % of all silicon atom-bonded functional groups

[0150] Component a-2-1: Linear organopolysiloxane capped at both terminals with alkenyl groups, represented by average structural formula ViMe.sub.2SiO(PhMeSiO).sub.25SiMe.sub.2Vi; phenyl groups account for 44.6 mol % of all silicon atom-bonded functional groups

[0151] Component a-2-2: Organopolysiloxane represented by average structural formula ViMe.sub.2SiO(Me.sub.2SiO).sub.60(Ph.sub.2SiO).sub.30SiMe.sub.2Vi; phenyl groups account for 32.3 mol % of all silicon atom-bonded functional groups

[0152] Component b-1: Linear organopolysiloxane capped at both terminals with alkenyl groups, represented by average structural formula ViMe.sub.2SiO(Me.sub.2SiO).sub.150SiMe.sub.2Vi; phenyl groups account for 0 mol % of all silicon atom-bonded functional groups

[0153] Component b-2: Linear organopolysiloxane capped at both terminals with alkenyl groups, represented by average structural formula ViMe.sub.2SiO(Me.sub.2SiO).sub.310SiMe.sub.2Vi; phenyl groups account for 0 mol % of all silicon atom-bonded functional groups

[0154] Component b-3: Linear organopolysiloxane capped at both terminals with alkenyl groups, represented by average structural formula ViMe.sub.2SiO(Me.sub.2SiO).sub.530SiMe.sub.2Vi; phenyl groups account for 0 mol % of all silicon atom-bonded functional groups

[0155] Component b-4: Linear organopolysiloxane containing alkenyl groups in side chains, represented by average structural formula Me.sub.3SiO(ViMeSiO).sub.7(Me.sub.2SiO).sub.800SiMe.sub.3; phenyl groups account for 0 mol % of all silicon atom-bonded functional groups

[0156] Component b-5: Linear organopolysiloxane capped at both terminals with alkenyl groups, represented by average structural formula ViPh.sub.2SiO(Me.sub.2SiO).sub.12SiPh.sub.2Vi; phenyl groups account for 13.3 mol % of all silicon atom-bonded functional groups

[0157] Component b-6: Linear organopolysiloxane capped at both terminals with alkenyl groups, represented by average structural formula ViMe.sub.2SiO(Me.sub.2SiO).sub.200(Ph.sub.2SiO).sub.50SiMe.sub.2Vi; phenyl groups account for 19.8 mol % of all silicon atom-bonded functional groups

[0158] Component b-7: Linear organopolysiloxane capped at both terminals with hydrogensiloxy groups, represented by average structural formula HMe.sub.2SiO(Me.sub.2SiO).sub.20SiMe.sub.2H; phenyl groups account for 0 mol % of all silicon atom-bonded functional groups

[0159] Component b-8: Linear organopolysiloxane containing hydrogensiloxy groups in side chains, represented by average structural formula Me.sub.3SiO(HMeSiO).sub.50SiMe.sub.3; phenyl groups account for 0 mol % of all silicon atom-bonded functional groups

[0160] Component b-9: Cerium-containing dimethylpolysiloxane; phenyl groups account for 0 mol % of all silicone atom-bonded functional groups

[0161] Component b′-1: Organopolysiloxane represented by average unit formula (Me.sub.3SiO.sub.1/2).sub.45 (ViMe.sub.2SiO.sub.1/2).sub.15 (SiO.sub.4/2).sub.40

[0162] Component b′-2: Organopolysiloxane represented by average unit formula (HMe.sub.2SiO.sub.1/2).sub.4(SiO.sub.4/2)

[0163] Component b′-3: Organopolysiloxane represented by average unit formula (Me.sub.2SiO.sub.2/2)(ViMeSiO.sub.2/2)(EpSiO.sub.3/2)

[0164] Component b′-4: Bismalate

[0165] Component b′-5: Organopolysiloxane represented by average unit unit (ViMe.sub.2SiO.sub.1/2).sub.3(MeSiO.sub.3/2)

[0166] Component b′-6: Organopolysiloxane represented by average structural formula ViMe.sub.2SiO(Me.sub.2SiO).sub.60(Ph.sub.2SiO).sub.30SiMe.sub.2Vi

[0167] Component b′-7: Organopolysiloxane represented by average unit formula (Me.sub.3SiO.sub.1/2).sub.5(ViMe.sub.2SiO.sub.1/2).sub.17(MeSiO.sub.3/2).sub.39(PhSiO.sub.3/2).sub.39

[0168] Component c-1: Organohydrogenpolysiloxane represented by average structural formula HMe.sub.2SiO(Ph.sub.2SiO)SiMe.sub.2H

[0169] Component c-2: Organohydrogenpolysiloxane represented by average unit formula (HMe.sub.2SiO.sub.1/2).sub.60(PhSiO.sub.3/2).sub.40

[0170] Component d-1: Complex of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane and platinum having a platinum concentration of 4.0% by mass

[0171] Component e-1: Epoxy group- and alkenyl group-containing resinous organopolysiloxane represented by average unit formula (ViMe.sub.2SiO.sub.1/2).sub.25 (EpMeSiO.sub.2/2).sub.40(PhSiO.sub.3/2).sub.75

[0172] Component e-2: Structural unit formula (ViMeSiO.sub.2/2).sub.4

[0173] Component f-1: Silica with an average primary particle size of 7 nm (brand name DM-30 by Tokuyama Corporation)

[0174] Component f-2: Carbon black with an average primary particle size of 280 nm (brand name N990 by Cancarb Limited)

[0175] Component f-3: Carbon black with an average primary particle size of 13 nm (brand name FW200 by Orion Engineered Carbons)

[0176] Component f-4: Glass bubbles with a median diameter of 18 μm (brand name iM30K by 3M)

[0177] Component g: Ethinylcyclohexanol

[0178] Preparation of Cured Product

[0179] The components were mixed in the proportions (% by mass) shown in Tables 1 through 6, and were stirred for 2 minutes at a vacuum of 1.8 Pa using a planetary stirring-defoaming device Mazerustar KK-VT300 by Kurabo Industries Ltd. The curable silicone compositions were coated to a thickness of 250 μm on glass plates (100 mm×100 mm) using a coater, placed in a heat circulation type of oven, held for 30 minutes at 150° C., and allowed to cool down to room temperature to produced cured products.

[0180] Evaluation

[0181] All compositions in the examples and comparative examples were assessed as follows for cured product surface smoothness and glass substrate wetting properties; the results are shown in Tables 1 through 6.

[0182] Surface Smoothness

[0183] The surfaces of the cured products that had been coated onto the glass plates were observed using a laser microscope (VK-X1000) by Keyence, where cured products with wrinkles on the surface were rated “x”, and cured product with no wrinkles on the surface were rated as “◯”.

[0184] Glass Substrate Wetting Properties

[0185] The cured products that had been coated onto the glass plates were macroscopically observed, where cured products that were peeling off the glass were rated “x”, and those with no peeling were rated as “◯”.

TABLE-US-00001 TABLE 1 Compar- Compar- ative ative Example Example Example Example Example Component 1 2 3 1 2 a-1 66.9 66.9 66.9 66.9 66.9 a-2-1 8.0 8.0 8.0 8.0 8.0 b-1 0.3 — — — — b-2 — 0.3 — — — b-3 — — 0.3 — — b′-1 — — — 0.3 — e-1 1.9 1.9 1.9 1.9 1.9 c-1 22.9 22.9 22.9 22.9 22.9 Total 100 100 100 100 100 organopolysiloxane components d-1 72 ppm 72 ppm 72 ppm 72 ppm 72 ppm G 0.05 0.05 0.05 0.05 0.05 Evaluation Surface smoothness ∘ ∘ ∘ x x Glass substrate ∘ ∘ ∘ x x wetting properties

TABLE-US-00002 TABLE 2 Example Example Example Example Example Component 4 5 6 7 8 a-1 66.9 66.9 66.9 66.9 66.9 a-2-1 8.0 8.0 8.0 8.0 8.0 b-1 0.3 — — — — b-2 — 0.3 — — — b-3 — — 0.3 — — b-4 — — — 0.3 — 6-5 — — — — 0.3 e-1 1.9 1.9 1.9 1.9 2.1 c-1 22.9 22.9 22.9 18.9 24.7 Total 100 100 100 100 100 organopolysiloxane components d-1 72 ppm 72 ppm 72 ppm 72 ppm 8 ppm f-1 0.58 0.58 0.58 0.58 0.06 f-2 0.58 0.58 0.58 0.58 0.06 G 0.05 0.05 0.05 0.05 0.05 Evaluation Surface ∘ ∘ ∘ ∘ ∘ smoothness Glass substrate ∘ ∘ ∘ ∘ ∘ wetting properties

TABLE-US-00003 TABLE 3 Example Example Example Example Example Component 9 10 11 12 13 a-1 66.9 66.9 66.9 56.6 72.3 a-2-1 8.0 8.0 8.0 21.9 0.80 b-1 — — — 0.58 0.06 b-6 0.3 — — — — b-7 — 0.3 — — — b-8 — — 0.3 — — e-1 1.9 1.9 1.9 1.9 2.1 c-1 22.9 22.9 22.9 18.9 24.7 Total 100 100 100 100 100 organopolysiloxane components d-1 72 ppm 72 ppm 72 ppm 72 ppm 8 ppm f-1 0.58 0.58 0.58 0.58 0.06 f-2 0.58 0.58 0.58 0.58 0.06 G 0.05 0.05 0.05 0.05 0.05 Evaluation Surface ∘ ∘ ∘ ∘ ∘ smoothness Glass substrate ∘ ∘ ∘ ∘ ∘ wetting properties

TABLE-US-00004 TABLE 4 Example Example Example Example Example Example Example Component 14 15 16 17 18 19 20 a-1 67.1 66.3 66.9 66.9 63.8 57.9 56.8 a-2-1 8.0 8.0 8.0 8.0 12.2 — 17.4 a-2-2 — — — — — 18.0 — b-2 0.1 1.0 0.3 0.3 0.1 — 0.3 b-9 — — — — — 1.0 1.0 e-1 1.9 1.9 1.9 1.9 2.2 2.5 2.3 e-2 — — — — — 0.2 0.2 c-1 22.9 22.8 22.9 22.9 21.7 20.3 19.7 c-2 — — — — — — 2.3 Total 100 100 100 100 100 100 100 organopoly siloxane components d-1 72 ppm 72 ppm 72 ppm 72 ppm 38 ppm 53 ppm 72 ppm f-1 0.58 0.58 0.58 0.58 0.09 0.58 0.67 f-2 0.58 0.58 5.80 — 0.55 1.00 1.00 f-3 — — — 0.58 — — f-4 — — — — 8.8 — — G 0.05 0.05 0.05 0.05 0.05 0.03 0.05 Evaluation Surface smoothness ∘ ∘ ∘ ∘ ∘ ∘ ∘ Glass substrate ∘ ∘ ∘ ∘ ∘ ∘ ∘ wetting properties

TABLE-US-00005 TABLE 5 Compar- Compar- Compar- Compar- Compar- ative ative ative ative ative Example Example Example Example Example Component 3 4 5 6 7 a-1 65.1 63.5 66.9 66.9 66.9 a-2-1 7.5 7.5 8.0 8.0 8.0 b-2 2.90 4.84 — — — b'-1 — — 0.3 — — b'-2 — — — 0.3 — b'-3 — — — — 0.3 e-1 1.9 1.9 1.9 1.9 1.9 c-1 22.6 22.2 22.9 22.9 22.9 Total 100 100 100 100 100 organopolysiloxane components D 72 ppm 72 ppm 72 ppm 72 ppm 72 ppm f-1 0.58 0.58 0.58 0.58 0.58 f-2 0.58 0.58 0.58 0.58 0.58 G 0.05 0.05 0.05 0.05 0.05 Evaluation Surface x x x ∘ x smoothness Glass substrate x x x x x wetting properties

TABLE-US-00006 TABLE 6 Compar- Compar- Compar- Compar- Compar- ative ative ative ative ative Example Example Example Example Example Component 8 9 10 11 12 a-1 66.9 66.9 66.9 66.9 66.9 a-2-1 8.0 8.0 8.0 8.0 8.3 b'-4 0.3 — — — — b' -5 — 0.3 — — — b'-6 — — 0.3 — — b'-7 — — — 0.3 — e-1 1.9 1.9 1.9 1.9 1.9 c-1 22.9 22.9 22.9 22.9 22.9 Total 100 100 100 100 100 organopolysiloxane components D 72 ppm 72 ppm 72 ppm 72 ppm 72 ppm f-1 0.58 0.58 0.58 0.58 0.58 f-2 0.58 0.58 0.58 0.58 0.58 G 0.05 0.05 0.05 0.05 0.05 Evaluation Surface x x x x x smoothness Glass substrate x x x x x wetting properties

[0186] The above results show that the curable silicone compositions of Examples 1 through 20 of the present disclosure were capable of forming cured products that had a smooth surface configuration on which wrinkling had been prevented. The curable silicone compositions of Examples 1 to 20 of the present disclosure also had exceptional wetting properties on glass substrates.

INDUSTRIAL APPLICABILITY

[0187] The curable silicone composition of the present disclosure is particularly useful as an encapsulating material for optical semiconductor devices, such as light emitting diodes (LEDs), semiconductor lasers, photodiodes, phototransistors, solid-state imaging, and light emitters and light receivers for photocouplers, etc.