A polysilazane having a ratio of the amount of SiH.sub.3 exceeding 0.050 and a ratio of the amount of NH of less than 0.045, based on the amount of aromatic ring hydrogen of xylene when .sup.1H-NMR of a 17% by mass solution of polysilazane dissolved in xylene is measured. A siliceous film-forming composition comprising the polysilazane. A method for producing a siliceous film comprising applying the polysilazane composition above a substrate.

Provided is a barrier film that includes a base layer (A), and a barrier layer (B) located on one side of the base layer and including one or more cured layers of polysilazane layers having a surface (S) of a concavo-convex structure formed by protruding particles, the barrier film having excellent barrier properties against the external environment, and excellent optical properties. The barrier film can be used for an electronic product sensitive to moisture.

Provided is a barrier film that includes a base layer (A), and a barrier layer (B) located on one side of the base layer and including one or more cured layers of polysilazane layers having a surface (S) of a concavo-convex structure formed by protruding particles, the barrier film having excellent barrier properties against the external environment, and excellent optical properties. The barrier film can be used for an electronic product sensitive to moisture.

A transparent coating film forming composition contains: (A) a polysilazane having units represented by the following formulae (1) and (2), and having predetermined modification rate and weight average molecular weight, ##STR00001##
(B) an organic solvent containing (B-1) and (B-2), (B-1) an organic solvent having a dielectric constant of 2.1 to 15.0 on average and a higher boiling point under atmospheric pressure (1013 hPa) than that of an organic solvent contained as the component (B-2), and (B-2) a saturated aliphatic hydrocarbon organic solvent; and (C) a predetermined curing catalyst. The mixing ratio of the component (A) and the component (B) satisfies a predetermined range. This provides a transparent coating film forming composition using an organic solvent having high polysilazane solubility, volatility at an appropriate speed during application, high safety and workability, the composition enabling formation of a coating film that is uniform and has high transparency and hardness after curing.

Si-containing film forming compositions are disclosed comprising a precursor having the formula [—NR—R.sup.4R.sup.5Si—(CH.sub.2).sub.t—SiR.sup.2R.sup.3—].sub.n wherein n=2 to 400; R, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 are independently H, a hydrocarbon group, or an alkylamino group, and provided that at least one of R.sup.2, R.sup.3, R.sup.4, and R.sup.5 is H; and R is independently H, a hydrocarbon group, or a silyl group. Exemplary pre-cursors include, but are not limited to, [—NH—SiH.sub.2—CH.sub.2—SiH.sub.2—].sub.n, and [—N(SiH.sub.2—CH.sub.2—SiH.sub.3)—SiH.sub.2—CH.sub.2—SiH.sub.2—].sub.n.

Si-containing film forming compositions are disclosed comprising a precursor having the formula [—NR—R.sup.4R.sup.5Si—(CH.sub.2).sub.t—SiR.sup.2R.sup.3—].sub.n wherein n=2 to 400; R, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 are independently H, a hydrocarbon group, or an alkylamino group, and provided that at least one of R.sup.2, R.sup.3, R.sup.4, and R.sup.5 is H; and R is independently H, a hydrocarbon group, or a silyl group. Exemplary pre-cursors include, but are not limited to, [—NH—SiH.sub.2—CH.sub.2—SiH.sub.2—].sub.n, and [—N(SiH.sub.2—CH.sub.2—SiH.sub.3)—SiH.sub.2—CH.sub.2—SiH.sub.2—].sub.n.

A composition comprising a silicon-based polymer, and a derivatized carbon nano-particle is provided. Further, a method for coating a substrate, coated substrates and articles comprising a substrate coated with the composition are provided.

A composition comprising a silicon-based polymer, and a derivatized carbon nano-particle is provided. Further, a method for coating a substrate, coated substrates and articles comprising a substrate coated with the composition are provided.

A mixed composition including an organosilicon compound (A) in which at least one trialkylsilyl group-containing molecular chain and at least one hydrolyzable group are bonded to a silicon atom, a metal compound (B), an acid (C), and water (D), in which a molar ratio (C/D) of the acid (C) to the water (D) is 0.002 to 0.15.

According to the present invention, a siliceous film forming composition, which is capable of filling trenches having narrow widths and high aspect ratios and forming a thick film, can be provided. A siliceous film forming composition comprising: (a) a block copolymer comprising a linear and/or cyclic block A having a polysilane skeleton comprising 5 or more silicon and a block B having a polysilazane skeleton comprising 20 or more silicon, and (b) a solvent.