[Problem] To provide a novel polymer, which fills trenches having narrow widths and high aspect ratios and can form a thicker film. [Means for Solution] The block copolymer comprises a linear 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.

Methods for forming a coated digitally manufactured part include forming an article by a digital manufacturing method; coating a surface of the article with a reactive silicon-containing precursor polymer; and treating the polymer to form a silica-containing coating, thereby forming the coated digitally manufactured part. An article includes a digitally manufactured part having surface striations; and a coating encapsulating the digitally manufactured part and comprising silica. An article includes a digitally manufactured part (i) formed by selective lase sintering, (ii) comprising a surface defined by coalesced particles, and (iii) having a surface roughness R.sub.a of at least 0.1 microns; and a coating encapsulating the part and comprising silica. A composition comprising polysilazane is described.

The present disclosure relates to a composition including a light-emitting perovskite compound (1) which includes constituent components A, B, and X, and a silazane or modified product thereof (2).

Described herein are compositions and methods for use in automotive care. In particular, the present disclosure is directed to water-based compositions comprising silicone combinations that delivery cleaning, protective, preservative and shine qualities.

Disclosed are a silazane-based compound represented by Formula 1, a coating composition containing the silazane-based compound, a light-transmitting film including a first coating layer containing the silazane-based compound, and a display apparatus including the light-transmitting film.

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A method for manufacturing a part made of composite material includes forming a ceramic matrix phase in pores of a fibrous preform by pyrolysis of a cross-linked copolymer ceramic precursor, the cross-linked copolymer including a first precursor macromolecular chain of a first ceramic having free carbon, and a second precursor macromolecular chain of a second ceramic having free silicon, the first macromolecular chain being bonded to the second macromolecular chain by cross-linking bridges including a bonding structure of formula *.sup.1—X—*.sup.2; in this formula, X designates boron or aluminium, -*.sup.1 designates the bond to the first macromolecular chain and -*.sup.2 the bond to the second macromolecular chain.

A method for manufacturing a part made of composite material includes forming a ceramic matrix phase in pores of a fibrous preform by pyrolysis of a cross-linked copolymer ceramic precursor, the cross-linked copolymer including a first precursor macromolecular chain of a first ceramic having free carbon, and a second precursor macromolecular chain of a second ceramic having free silicon, the first macromolecular chain being bonded to the second macromolecular chain by cross-linking bridges including a bonding structure of formula *.sup.1—X—*.sup.2; in this formula, X designates boron or aluminium, -*.sup.1 designates the bond to the first macromolecular chain and -*.sup.2 the bond to the second macromolecular chain.

A method for treating surface of substrate, the method including forming a film including a high molecular weight condensate of a silylation agent on the surface thereof to allow a substrate having a plurality of regions to be modified at modification degrees that are different depending on materials of the regions on a surface of the substrate. The method includes preparing a substrate having a surface including two or more regions having different materials; exposing the surface to a surface treatment agent; and baking the substrate, the method not including rinsing the surface with a liquid between the exposing and the baking, the surface treatment agent including a silylation agent and not a nitrogen-containing heterocyclic compound, the silylation agent including organomonosilane that has 2 to 4 nitrogen atoms bonded to a silicon atom.

A method for treating surface of substrate, the method including forming a film including a high molecular weight condensate of a silylation agent on the surface thereof to allow a substrate having a plurality of regions to be modified at modification degrees that are different depending on materials of the regions on a surface of the substrate. The method includes preparing a substrate having a surface including two or more regions having different materials; exposing the surface to a surface treatment agent; and baking the substrate, the method not including rinsing the surface with a liquid between the exposing and the baking, the surface treatment agent including a silylation agent and not a nitrogen-containing heterocyclic compound, the silylation agent including organomonosilane that has 2 to 4 nitrogen atoms bonded to a silicon atom.

[Problem] To provide a polycarbosilazane making it possible to form a silicon-containing film which is bearable to acid etching, and a composition comprising the polycarbosilazane. [Means for Solution] The present invention provides a polycarbosilazane comprising a repeating unit of —[R.sup.1R.sup.2Si—(CH.sub.2).sub.n]— and —(R.sup.3R.sup.4Si—NR.sup.5)—, wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently a single bond, hydrogen or C.sub.1-4 alkyl; R.sup.5 is independently a single bond or hydrogen; and n is 1-2, and a composition comprising the polycarbosilazane. The present invention also provides a method for forming a silicon-containing film, comprising coating the composition above a substrate and heating.