Organopolysiloxane cured product film and usage, manufacturing method, and manufacturing apparatus therefor

An organopolysiloxane cured film in which an arithmetic average height (Sa) of the film surface is less than 0.50 μm, while an average thickness at the center of the film is within a range of 1 to 20 μm;

• wherein the organopolysiloxane cured film is obtained by curing a curable organopolysiloxane composition comprising:
• (A) an organopolysiloxane with at least two curing reactive groups having a carbon-carbon double bond in a molecule;
• (B) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in a molecule in an amount in which the silicon-bonded hydrogen atoms are within a range of 0.1 to 2.5 mols per 1 mol of carbon-carbon double bonds in component (A);
• (C) an effective amount of a hydrosilylation reaction catalyst;
• (D1) reinforcing fine particles or a composite thereof having an average BET specific surface area of greater than 100 m2/g that are surface treated with one or more types of organic silicon compounds;
• and
• (D2) reinforcing fine particles or a composite thereof having an average BET specific surface area within a range of 10 to 100 m2/g that are surface treated with one or more types of the organic silicon compounds, where the one or more types of the organic silicon compounds are the same as or different from the one or more types of organic silicon compounds used to treat component (D1);
• wherein a portion or all of component (A) or component (B) is an organopolysiloxane or an organohydrogenpolysiloxane, respectively, having a high dielectric functional group selected from:
• a) halogen atoms and groups containing a halogen atom;
• b) groups containing a nitrogen atom;
• c) groups containing an oxygen atom;
• d) heterocyclic groups;
• e) groups containing a boron atom;
• f) groups containing phosphorus;
• and g) groups containing a sulfur atom;
• wherein the mass ratio of component (D1) and component (D2) is within a range of 50:50 to 99:1;
• wherein the total viscosity of the curable organopolysiloxane composition measured at 25° C. and a shear rate of 10.0 (S−1) is within the range of 1,000 to 100,000 mPa·s;
• and
• wherein the organopolysiloxane cured film has the following mechanical properties measured when heated and molded into a sheet having a thickness of 2.0 mm, based on JIS K 6249:
• (1) the Young's modulus (MPa) at room temperature is within a range of 0.1 to 2.5 MPa;
• (2) the tear strength (N/mm) at room temperature is within a range of 2 N/mm or higher;
• (3) the tensile strength (MPa) at room temperature is within a range of 2 MPa or higher;
• and
• (4) the elongation at break (%) is within a range of 200 to 1000%.