Abstract: An epoxy resin composition for encapsulating optical semiconductor element, comprising the following (A) to (D): (A) an epoxy resin component comprising a novolak type epoxy resin having at least one of the biphenyl skeleton and naphthalene skeleton in one molecule in an amount of from 50 to 100% by weight of the total weight of the epoxy resin component, (B) a curing agent component comprising a novolak type phenol resin having at least one of the biphenyl skeleton and naphthalene skeleton in one molecule in an amount of from 50 to 100% by weight of the total weight of the curing agent component, (C) an organic phosphorus flame retarder, and (D) a curing catalyst, wherein the content of an organic phosphorus flame retarder as (C) is from 1.

Abstract: The resin composition of the present invention comprises (A) a resin composition comprising a polyphenylene ether resin or a polyphenylene ether resin and a polystyrene resin and (B) a phosphazene compound having an acid value of less than 0.5. This resin composition contains no halogen compounds and hence is environmentally preferred, and furthermore is excellent in electrical characteristics, heat resistance and mechanical properties, causes substantially no problems such as smoking during injection molding and desposition of flame-retardants on the mold, and has high flame retardancy.

Abstract: The present invention has an object to provide a flame-retardant epoxy resin composition excellent in heat resistance and moisture resistance. A flame-retardant epoxy resin composition relating to the present invention contains an epoxy resin (A), a phosphazene compound (B), an epoxy hardener (C) and an inorganic filler (D), wherein the phosphazene compound (B) and the epoxy hardener (C) are included in the range of 0.

Abstract: A polyalkylene terephthalate-series resin (e.g., polyethylene terephthalate-series resin, polybutylene terephthalate-series resin) is improved in flame retardancy by using a flame retardant containing a phosphazene compound and a phenolic resin. The phosphazene compound is a compound shown by the following formulae (1) and/ or (2), and/or a compound being the above compound crosslinked with a phenylene group or a crosslinking group shown by the following formula (3a). The proportion of the phosphazene compound to the phenolic resin is the former/the latter=5/95 to 95/5 (weight ratio). By means of the above flame retardant, a polyalkylene terephthalate-series resin can be highly improved in flame retardancy without deteriorating the properties. Further, by adding the other flame retardant (e.g., a nitrogen-containing flame retardant, a phosphate-series flame retardant), and a carbonizable resin, the flame retardancy can be enhanced.

Abstract: A flame retardant comprising a phosphazene compound, a polyphenylene oxide-series resin, and if necessary a styrenic resin and/or a nitrogen-containing compound imparts flame retardancy to a polyalkylene arylate-series resin. The phosphazene compound comprises at least a crosslinked phenoxyphosphazene compound. The obtained polyalkylene arylate-series resin composition shows high flame-retardancy.

Abstract: An improved phenoxyphosphazene compound is produced by treating a phenoxyphosphazene compound with (a) at least one adsorbent selected from activated carbon, silica gel, activated alumina, activated clay, synthetic zeolite and macromolecular adsorbents, (b) at least one reagent selected from metal hydrides, hydrazine, hypochlorites, thiosulfates, dialkyl sulfuric acids, ortho esters, diazoalkanes, lactones, alkanesultones, epoxy compounds and hydrogen peroxide, or (c) both the adsorbent and reagent, thereby reducing the acid value of said phosphazene compound to lower than 0.025 mgKOH/g.

Abstract: A heat-resistant composition contains solvent-soluble polyimide resin (A) and a phosphazene compound (B) in relation to a polyimide resin composition having solubility in a low-boiling solvent, heat resistance, flame resistance, adhesiveness and mechanical properties. The said phosphazene compound (B) is a cyclic phenoxyphosphazene compound (B1) expressed in the following chemical formula (1): where m represents an integer of 3 to 25 and Ph represents a phenyl group.

Abstract: A flame-retardant resin composition comprising a phosphazene flame retardant and a polyester resin, wherein the flame retardant is bonded to the molecules of the polyester resin via the ester group thereof, can retain a high flame retardance for a prolonged term with little or no vaporization with time and is excellent in flame retardance, impact resistance, properties and processability.

Abstract: A powdery flame retardant which is obtained by mixing a flame retardant which is liquid or a viscous solid at ordinary temperature with an inorganic fibrous substance to adhere or adsorb the retardant to the fibrous substance, and which comprises 5 to 70 wt. % the flame retardant and 95 to 30 wt. % the fibrous substance. The powdery flame retardant can be easily handled because it is a powder, and is obtained by a simple and industrially advantageous method. It produces a remarkable effect that the performance of the liquid or viscous flame retardant is not impaired.

Abstract: The resin composition of the present invention comprises (A) a resin composition comprising a polyphenylene ether resin or a polyphenylene ether resin and a polystyrene resin and (B) a phosphazene compound having an acid value of less than 0.5. This resin composition contains no halogen compounds and hence is environmentally preferred, and furthermore is excellent in electrical characteristics, heat resistance and mechanical properties, causes substantially no problems such as smoking during injection molding and deposition of flame-retardants on the mold, and has high flame retardancy.

Abstract: The present invention has an object to provide a flame retardant excellent in heat resistance and hard to cause juicing or mold deposits in molding. A flame retardant relating to the present invention has a feature to be made of a polymer constituted of at least one kind, as a building block, among phosphazene compounds each having, in a molecule thereof, at least one of one kind of polymerizable functional group selected from the group consisting of a vinyl group, an allyl group, an acryloyloxy group, a methacryloyloxy group, an acryloyl group, and a methacryloyl group.

Abstract: The epoxy resin of the invention comprises (A) an epoxy resin, (B) at least one member selected from the group consisting of a phenolic hydroxyl group-containng compound, a urea resin and a melamine resin, (C) a crosslinked phenoxyphosphazene compound, and (D) an inorganic filler powder, the amount of component (C) being in the range of 0.01 to 30 wt. % based on the total amount of components (A), (B) and (C), and the amount of component (D) being in the range of 60 to 98 wt. % based on the total amount of components (A), (B), (C) and (D). The epoxy resin composition of the invention and a molded product are halogen-free and antimony-free and are excellent in flame retardancy. When an element for an electronic part such as LSI and VLSI is encapsulated by the epoxy resin composition of the invention, the obtained electronic part is outstanding in heat resistance, moisture resistance, thermal impact resistance and like properties.

Abstract: A halogen-free nonflammable epoxy resin composition, which comprises, as essential components (A) at least one kind of a cross-linked phenoxyphosphazene compound, (B) at least one kind of polyepoxide compound such as bisphenol A epoxy resin, (C) a curing agent for epoxy such as bisphenol A novolac resin, and (D) a cure promoter for epoxy, wherein the epoxy resin composition further comprises 0 to 50% by weight of an inorganic filler.

Abstract: This invention has an object of providing a flame retardant which advantageously has a high melting point and a low volatility and is unlikely to depress the inherent properties of resins. The flame retardant of the invention is a phosphazene compound crosslinked with a crosslinking group such as phenylene group, each of the crosslinking groups being interposed between the two oxygen groups left after the elimination of phenyl groups from the phosphazene compound, the amount of the phenyl groups in the crosslinked compound being 50 to 99.9% based on the total number of the phenyl groups in the phosphazene compound. The invention also provides a resin composition containing the flame retardant, and a molded article of the resin.

Abstract: The present invention has an object to provide a flame-retardant epoxy resin composition excellent in heat resistance and moisture resistance. A flame-retardant epoxy resin composition relating to the present invention contains an epoxy resin (A), a phosphazene compound (B), an epoxy hardener (C) and an inorganic filler (D), wherein the phosphazene compound (B) and the epoxy hardener (C) are included in the range of 0.

Abstract: This invention has an object of providing a flame retardant which advantageously has a high melting point and a low volatility and is unlikely to depress the inherent properties of resins. The flame retardant of the invention is a phosphazene compound crosslinked with a crosslinking group such as phenylene group, each of the crosslinking groups being interposed between the two oxygen groups left after the elimination of phenyl groups from the phosphazene compound, the amount of the phenyl groups in the crosslinked compound being 50 to 99.9% based on the total number of the phenyl groups in the phosphazene compound. The invention also provides a resin composition containing the flame retardant, and a molded article of the resin.

Abstract: This invention provides a halogen-free flame retardant which advantageously has a high melting point and a low volatility and does not impair the inherent properties of resins. The flame retardant of the invention is a phosphazene compound crosslinked with a crosslinking group such as a phenylene group, wherein each of the crosslinking groups is interposed between the two oxygen groups left after the elimination of phenyl groups from the phosphazene compound; the crosslinked phenoxyphosphazene compound does not have any free hydroxyl groups (derived from crosslinking groups); and the amount of the phenyl groups in the crosslinked compound is 50 to 99.9%, based on the total number of the phenyl groups in the phosphazene compound.

Abstract: The phenoxyphosphazene compound of the present invention is prepared by treating a phenoxyphosphazene compound with (a) at least one adsorbent selected from activated carbon, silica gel, activated alumina, activated clay, synthetic zeolite and macromolecular adsorbents, (b) at least one reagent selected from metal hydrides, hydrazine, hypochlorites, thiosulfates, dialkyl sulfuric acids, ortho esters, diazoalkanes, lactones, alkanesultones, epoxy compounds and hydrogen peroxide or (c) both the adsorbent and reagent.

Abstract: An object of this invention is to impart excellent flame retardancy to an aromatic polyamide resin without use of a halogen compound which is responsible for generation of gases harmful to the human body and without decreasing preferred properties (e.g. mechanical properties, and molding processability) inherently possessed by aromatic polyamide resins, the flame-retardant aromatic polyamide resin composition of this invention comprising (a) 100 parts by weight of an aromatic polyamide resin, (b) 0.1 to 100 parts by weight of a crosslinked phosphazene compound which is a compound crosslinked with a crosslinking group, such as phenylene groups, the crosslinking group being interposed between the two oxygen atoms left after the elimination of phenyl groups from the phosphazene compound, no free hydroxyl group being present in the molecule, the amount of all phenyl groups in the crosslinked compound being 50 to 99.

Abstract: This invention provides a flame-retardant resin composition comprising: (A) 100 parts by weight of a thermoplastic resin other than a thermotropic liquid crystal polymer, (B) 0.01 to 50 parts by weight of a thermotropic liquid crystal polymer, and (C) 1 to 30 parts by weight of a halogen-free phosphazene compound, the invention providing a novel flame-retardant resin composition which is free of the problems arising due to the presence of halogen element, the composition being excellent in flame retardancy, mechanical properties, molding processability and the like, and being unlikely to cause dripping.