Free films made of cured organopolysiloxane resins, process for production thereof, and laminated films

1. A free-standing film comprising a cured organopolysiloxane resin, wherein the glass transition temperature of the cured organopolysiloxane resin is equal to or greater than 100° C. and the coefficient of thermal expansion at 100° C. is equal to or below 200 ppm/K, obtained by conducting a cross-linking reaction between

(A) an organopolysiloxane resin represented by the following average siloxane unit formula:

[R 1 a R 2 3-a SiO 1/2 ] v [R 3 SiO 3/2 ] w   (1) or

[R 1 a R 2 3-a SiO 1/2 ] x [R 3 SiO 3/2 ] y [SiO 4/2 ] z   (2)

where R 1 designates univalent hydrocarbon groups of one or more than one type selected from alkyl groups having 1 to 4 carbon atoms and univalent aromatic hydrocarbon groups having 6 to 8 carbon atoms; R 2 designates alkenyl groups having 2 to 6 carbon atoms; R 3 designates univalent hydrocarbon groups of one or more than one type selected from alkyl groups with 1 to 4 carbon atoms and univalent aromatic hydrocarbon groups having 6 to 8 carbon atoms; at least 50 mole % of R 3 groups being phenyl groups; “a” is 0, 1, or 2; 0.82≦w<1.0 and v+w=1; 0<x<0.4, 0.5<y<1, 0<z<0.4, and x+y+z=1; and

(B) an organosilicon compound that contains in one molecule two or more silicon-bonded hydrogen atoms, in which not less than 5 mole % of all silicon-bonded univalent groups are univalent aromatic hydrocarbon groups, in the presence of (C) a hydrosilylation catalyst.

2. The free-standing film of claim 1 , wherein the cured organopolysiloxane resin does not have a specific light-absorption band in the visible-light range, has a light transmittance of 85% or higher at the wavelength of 400 nm, and a light transmittance of 88% or higher in the wavelength range of 500 to 700 nm.

3. The free-standing film of claim 1 , wherein 0<x<0.3, 0.65<y<1, 0<z<0.2 and x+y+z=1.

4. A process for manufacturing a free-standing film comprising a cured organopolysiloxane resin, wherein the glass transition temperature of the cured organopolysiloxane resin is equal to or greater than 100° C. and the coefficient of thermal expansion at 100° C. is equal to or below 200 ppm/K, comprising the steps of:

coating a cross-linkable organopolysiloxane resin composition comprising:

(A) an organopolysiloxane resin represented by the following average siloxane unit formula:

[R 1 a R 2 3-a SiO 1/2 ] v [R 3 SiO 3/2 ] w   (1) or

[R 1 a R 2 3-a SiO 1/2 ] x [R 3 SiO 3/2 ] y [SiO 4/2 ] z   (2)

where R 1 designates univalent hydrocarbon groups of one or more than one type selected from alkyl groups having 1 to 4 carbon atoms and univalent aromatic hydrocarbon groups having 6 to 8 carbon atoms; R 2 designates alkenyl groups having 2 to 6 carbon atoms; R 3 designates univalent hydrocarbon groups of one or more than one type selected from alkyl groups with 1 to 4 carbon atoms and univalent aromatic hydrocarbon groups having 6 to 8 carbon atoms; at least 50 mole % of R 3 groups being phenyl groups; “a” is 0, 1, or 2; 0.82≦w<1.0 and v+w=1; 0<x<0.4, 0.5<y<1, 0<z<0.4, and x+y+z=1; and

(B) an organosilicon compound that contains in one molecule two or more silicon-bonded hydrogen atoms, in which not less than 5 mole % of all silicon-bonded univalent groups are univalent aromatic hydrocarbon groups, and (C) a hydrosilylation catalyst onto a substrate to form an uncured film;

forming a cured film by cross-linking the aforementioned uncured film; and

peeling the obtained cured film off from the substrate.

5. The process for manufacturing the free-standing film according to claim 4 , wherein the cured organopolysiloxane resin does not have a specific light-absorption band in the visible-light range, has a light transmittance of 85% or higher at the wavelength of 400 nm, and a light transmittance of 88% or higher in the wavelength range of 500 to 700 nm.

6. A layered film comprising a free-standing film comprising a cured organopolysiloxane resin, wherein the glass transition temperature of the cured organopolysiloxane resin is equal to or greater than 100° C. and the coefficient of thermal expansion at 100° C. is equal to or below 200 ppm/K, obtained by conducting a cross-linking reaction between

(A) an organopolysiloxane resin represented by the following average siloxane unit formula:

[R 1 a R 2 3-a SiO 1/2 ] v [R 3 SiO 3/2 ] w   (1) or

[R 1 a R 2 3-a SiO 1/2 ] x [R 3 SiO 3/2 ] y [SiO 4/2 ] z   (2)

where R 1 designates univalent hydrocarbon groups of one or more than one type selected from alkyl groups having 1 to 4 carbon atoms and univalent aromatic hydrocarbon groups having 6 to 8 carbon atoms; R 2 designates alkenyl groups having 2 to 6 carbon atoms; R 3 designates univalent hydrocarbon groups of one or more than one type selected from alkyl groups with 1 to 4 carbon atoms and univalent aromatic hydrocarbon groups having 6 to 8 carbon atoms; at least 50 mole % of R 3 groups being phenyl groups; “a” is 0, 1, or 2; 0.82≦w<1.0 and v+w=1; 0<x<0.4, 0.5<y<1, 0<z<0.4, and x+y+z=1; and

(B) an organosilicon compound that contains in one molecule two or more silicon-bonded hydrogen atoms, in which not less than 5 mole % of all silicon-bonded univalent groups are univalent aromatic hydrocarbon groups, in the presence of (C) a hydrosilylation catalyst,

and an inorganic layer on the free-standing film.

7. The layered film according to claim 6 , wherein the inorganic layer is a deposited layer of a metal or a metal oxide.

8. The layered film according to claim 6 , wherein the inorganic layer is a gas-barrier layer.