An ultra-white granular silica-based filler comprises at least 99.5 wt. % silica, wherein the crystal structure of the silica is such that the silica-based filler comprises 40 to 80 wt. % cristobalite, 1 to 25 wt. % tridymite, 2-60 wt. % quartz and <5 wt. % amorphous silica, wherein the temperature of the ultra-white granular silica-based filler is no higher than 50° C. and further wherein the ultra-white granular silica-based filler exhibits an L* value in the CIELAB color space of 95-98. In addition, an ultra-white powder filler is obtained by milling, grinding or comminuting the ultra-white granular silica-based filler. The ultra-white powder filler exhibits an L* value in the CIELAB color space of 95-98.5.

To achieve properties such as a desirable compression fracture property, desirable compression set, and the like in the elastomer composition and the seal material using same. The elastomer composition of the present disclosure therefore includes an elastomer, phenol resin in powder form, and silica in powder form. The seal material of the present disclosure is obtained by crosslinking and molding the elastomer composition of the present disclosure. The seal material may be used in a semiconductor manufacturing device.

A display device includes: s light-emitting element layer (11) including, on a thin film transistor layer (6), a plurality of light-emitting elements (11R, 11G, 11B) that each include a first electrode (7), a light-emitting-layer-including functional layer (9R, 9G, 9B), and a second electrode (10) and that emit light of different colors; and a sealing layer (12) disposed on the light-emitting element layer (11) so as to seal the light-emitting element layer (11), wherein the sealing layer (12) includes a first inorganic sealing film (12a) on the light-emitting element layer (11) and an organic sealing film (12b) on the first inorganic sealing film (12a), and the organic sealing film (12b) contains a polymer compound and a cyclic compound.

A composition containing a fluorine-containing polymer and a silicon oxide represented by formula: SiO.sub.x, where 0<x<2. In a preferred embodiment, the composition contains a cross-linking agent. Also disclosed is a crosslinked product which may be a sealing material obtained by crosslinking the composition.

Provided is a rubber composition for sealing material which contains 100 parts by mass of a rubber component, 50 to 140 parts by mass of silica, 1 to 20 parts by mass of a silane coupling agent, and 15 to 35 parts by mass of carbon black. The rubber component is preferably an ethylene-propylene-diene rubber.

An acrylic rubber composition that includes a blend product of an acrylic rubber [I] containing a copolymer of an ethyl acrylate/n-butyl acrylate/2-methoxyethyl acrylate/carboxyl group-containing vinyl monomer, and an acrylic rubber [II] containing a copolymer of an alkoxyalkyl acrylate/2-ethylhexyl acrylate/alkyl methacrylate/ethyl acrylate/carboxyl group-containing vinyl monomer; the blend product being compounded with silica and a plasticizer.

A gasket material comprising a crosslinked fluororubber layer having a micro-hardness of 5 to 25 formed on a metal plate using a fluororubber composition comprising 30 to 70 parts by weight of carbon black having a CTAB specific surface area of 3 to 34 m.sup.2/g, and 5 to 15 parts by weight of hydrated amorphous silicon dioxide having a BET specific surface area of 35 to 220 m.sup.2/g, based on 100 parts by weight of fluororubber, wherein the total amount of carbon black and hydrated amorphous silicon dioxide is 80 parts by weight or less.

This seal member is a cured product of a silicone rubber composition that comprises a silicone rubber and silica particles, and has multiple insertion holes into which counterpart members are inserted; and this seal member satisfies the following conditions (a) to (d). (a) If X (parts by mass) is the content of the silica particles relative to 100 parts by mass of a base polymer of the silicone rubber, (elastic recovery rate (%))/(X (parts by mass)) is from 3.6 to 9.6. (b) The type A durometer hardness is from 15 to 30. (c) The tensile strength at break is 2.1 MPa or more. (d) The coefficient of kinetic friction of the surfaces of the insertion holes is 2.5 or less.

An amorphous silica powder that is suitable for obtaining a liquid sealant that exhibits superior filling properties and preservation properties, and a resin composition obtained by using the amorphous silica powder as a filler. More specifically, an amorphous silica powder is prepared so as to have a modal diameter within the range of 1 to 10 μm and a frequency of particles having particle diameters of less than 0.50 μm of 1.0% or more in the particle diameter frequency distribution and have a specific surface area of 1 to 12 m.sup.2/g.

An ultra-white granular silica-based filler comprises at least 99.5 wt. % silica, wherein the crystal structure of the silica is such that the silica-based filler comprises 40 to 80 wt. % cristobalite, 1 to 25 wt. % tridymite, 2-60 wt. % quartz and <5 wt. % amorphous silica, wherein the temperature of the ultra-white granular silica-based filler is no higher than 50 C. and further wherein the ultra-white granular silica-based filler exhibits an L* value in the CIELAB color space of 95-98. In addition, an ultra-white powder filler is obtained by milling, grinding or comminuting the ultra-white granular silica-based filler. The ultra-white powder filler exhibits an L* value in the CIELAB color space of 95-98.5.