A film is provided with void spaces having a porous structure with less cracks and a high proportion of void space as well as having strength. The film with void spaces includes one kind or two or more kinds of structural units that form a structure with minute void spaces, wherein the structural units are chemically bonded through catalysis. For example, the abrasion resistance measured with BEMCOT® is in the range from 60% to 100%, and the folding endurance measured by the MIT test is 100 times or more. The film with void spaces can be produced by forming the precursor of the silicone porous body using sol containing pulverized products of a gelled silicon compound and then chemically bonding the pulverized products contained in the precursor of the silicone porous body. The chemical bond among the pulverized products is preferably a chemical crosslinking bond among the pulverized products.

A film is provided with void spaces having a porous structure with less cracks and a high proportion of void space as well as having strength. The film with void spaces includes one kind or two or more kinds of structural units that form a structure with minute void spaces, wherein the structural units are chemically bonded through catalysis. For example, the abrasion resistance measured with BEMCOT® is in the range from 60% to 100%, and the folding endurance measured by the MIT test is 100 times or more. The film with void spaces can be produced by forming the precursor of the silicone porous body using sol containing pulverized products of a gelled silicon compound and then chemically bonding the pulverized products contained in the precursor of the silicone porous body. The chemical bond among the pulverized products is preferably a chemical crosslinking bond among the pulverized products.

The present invention provides an optical member comprising a silicone material having excellent antifouling property while having good light transmittance, heat resistance, and strength, and an optical semiconductor device and illumination apparatus having excellent antifouling property. The present invention is an optical member comprising a silicone material containing a fluorinated surface, the proportion of F atoms being from 0.1 to 45 at % and/or the ratio of F atoms relative to C atoms being from 0.01 to 1.00 in the atomic composition percentage according to X-ray photoelectron spectroscopy (XPS) of the fluorinated surface.

Provided is a resin composition, a prepreg for a printed circuit and a metal-coated laminate. The resin composition includes: a silicone aryne resin, a polyphenylene ether resin with unsaturated bonds, and a butadiene polymer. The resin composition is used such that the prepared metal-coated laminate can have at least one of the following characteristics: a low dielectric loss factor, high heat resistance, and a low coefficient of thermal expansion.

Provided is a barrier film, comprising: a base layer; and an inorganic layer including Si, N, and O, wherein the inorganic layer has a thickness of 600 nm or less, and the film has a water vapor transmission rate of 0.5×10.sup.−3 g/m.sup.2.Math.day as measured under conditions of a temperature of 38° C. and 100% relative humidity. The barrier film has excellent barrier properties and optical properties and can be used for electronic products sensitive to moisture.

To provide a new silicon-containing polymer making it possible to form a cured film has features that its residual stress is small and crack resistance is high. A polycarbosilazane having particular cyclic structures.

The present invention is a gas barrier laminate comprising a base unit that comprises a base and a modification-promoting layer, and a gas barrier layer that is formed on a side of the modification-promoting layer with respect to the base unit, the modification-promoting layer having a modulus of elasticity at 23° C. of less than 30 GPa, the base unit having a water vapor transmission rate at a temperature of 40° C. and a relative humidity of 90% of 1.0 g/(m.sup.2.Math.day) or less, and the gas barrier layer being a layer formed by applying a modification treatment to a surface of a layer that comprises a polysilazane-based compound and is formed on the side of the modification-promoting layer with respect to the base unit, and a method for producing the gas barrier laminat, and an electronic device member comprising the gas barrier laminate, and an electronic device comprising the electronic device member.

[Problem] To provide a film forming composition and a film forming method capable of forming a film excellent in gas barrier properties. [Means for Solution] A film forming composition comprising a polysilazane, an organic solvent and an additive having a specific structure, and a film forming method comprising applying the composition on a substrate and exposing the composition to light. This specific additive is represented by a specific general formula among those having a nonconjugated cyclic structure composed of atoms selected from the group consisting of carbon, nitrogen and oxygen in the structure.

The present application relates to a method for preparing a barrier film. The present application can provide a method for preparing a barrier film having excellent barrier characteristics and optical performances. The barrier film produced by the method of the present application can be effectively used not only for packaging material for food or medicine, and the like, but also for various applications, such as LCDs (Liquid Crystal Displays) or a solar cells, substrates for electronic papers or OLEDs (Organic Light Emitting Diodes) or sealing films.

[Problem] To provide a composition for forming a coating layer having excellent gas barrier performance and a method of forming the coating layer. [Means for Solution] A composition for forming a coating film comprising a specific silicon compound which reacts with a polysilazane by exposure, a polysilazane and an organic solvent, and a method for forming a coating layer comprising coating the composition on a substrate and exposing.