A method for producing a liquid dispersion containing irregular-shaped silica particles in which two or more primary particles are linked together, by simultaneously adding a liquid A containing silane alkoxide and a liquid B containing an alkali catalyst and water to a liquid I consisting substantially of an organic solvent to cause hydrolysis and polycondensation of the silane alkoxide, wherein the period from the start of the addition until the silica concentration of the reaction system at the end of the addition reaches 70% is 20% or less of the full reaction time period.

Methods for strengthening edges of a laminated glass article comprising a glass core layer positioned between a first glass clad layer and a second glass clad layer are disclosed. The methods may comprise polishing the cut edges of the laminated glass article with a slurry of polishing media applied to the edges of the laminated glass article with brushes. An edge strength of the laminated glass article is greater than or equal to about 400 MPa after polishing.

Methods for strengthening edges of a laminated glass article comprising a glass core layer positioned between a first glass clad layer and a second glass clad layer are disclosed. The methods may comprise polishing the cut edges of the laminated glass article with a slurry of polishing media applied to the edges of the laminated glass article with brushes. An edge strength of the laminated glass article is greater than or equal to about 400 MPa after polishing.

Provided is a polishing composition that includes a cellulose derivative and is effective for reducing surface defects after polishing. According to the present application, a polishing composition comprising an abrasive, a basic compound and a surface protective agent is provided. The surface protective agent contains a cellulose derivative and a vinyl alcohol-based dispersant. The surface protective agent has a dispersibility parameter of less than 100.

A polishing composition for use in polishing an object to be polished, which comprises abrasive grains, a dispersing medium, and an additive, wherein the abrasive grains are surface-modified, the additive is represented by the following formula 1:

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wherein in the formula 1, X.sub.1 is O or NR.sub.4, X.sub.2 is a single bond or NR.sub.5, R.sub.1 to R.sub.5 are each independently a hydrogen atom; a hydroxy group; a nitro group; a nitroso group; a C.sub.1-4 alkyl group optionally substituted with a carboxyl group, an amino group, or a hydroxy group; or CONH.sub.2; with the proviso that R.sub.2 and R.sub.5 may form a ring; when X.sub.2 is a single bond, R.sub.3 is not a hydrogen atom, or R.sub.1 to R.sub.3 are not a methyl group; and when X.sub.2 is NR.sub.5 and three of R.sub.1 to R.sub.3 and R.sub.5 are a hydrogen atom, the other one is not a hydrogen atom or a methyl group; and a pH is 5.0 or less. According to the present invention, a polishing composition capable of polishing not only polycrystalline silicon but also a silicon nitride film at high speed and also suppressing a polishing speed of a silicon oxide film is provided.

The present invention provides a means allowing achievement of sufficient planarization of the surface of an object to be polished containing two or more types of materials. The present invention is a polishing method for polishing an object to be polished containing two or more types of materials by using a polishing composition, the polishing method including equalization of the surface zeta potential of the object to be polished.

The present invention provides a means allowing achievement of sufficient planarization of the surface of an object to be polished containing two or more types of materials. The present invention is a polishing method for polishing an object to be polished containing two or more types of materials by using a polishing composition, the polishing method including equalization of the surface zeta potential of the object to be polished.

Embodiments relate to a polishing pad, which comprises a window having a hardness similar to that of its polishing layer. Since the polishing pad comprises a window having a hardness and a polishing rate similar to those of its polishing layer, it can produce an effect of preventing scratches on a wafer during a CMP process. In addition, the polishing layer and the window of the polishing pad have a similar rate of change in hardness with respect to temperature, so that they can maintain a similar hardness despite a change in temperature during the CMP process.

Embodiments relate to a polishing pad, which comprises a window having a hardness similar to that of its polishing layer. Since the polishing pad comprises a window having a hardness and a polishing rate similar to those of its polishing layer, it can produce an effect of preventing scratches on a wafer during a CMP process. In addition, the polishing layer and the window of the polishing pad have a similar rate of change in hardness with respect to temperature, so that they can maintain a similar hardness despite a change in temperature during the CMP process.

Provided is a polishing composition that can reduce increase in temperature of a polishing pad during polishing. The polishing composition provided by the present invention contains water, oxidant A selected from compounds other than peroxide, a first metal salt selected from alkaline-earth metal salts, and a second metal salt selected from salts each of which has a cation of a metal belonging to groups 3 to 16 in the periodic table, and an anion.