Otsuka Chemical Co., Ltd.

Otsuka Kagaku Kabushiki Kaisha

Tadao Yabuhara

Yuji Tada

Yoichi Nishioka

Shinji Nakano

Takashi Kameshima

Hiroyuki Takase

Yoshifumi Nakacho

Masahiro Kobayashi

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.

Process for producing phenoxyphosphazene compound, flame-retardant resin composition, and flame-retardant resin molding

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.

Flame-retardant resin, composition thereof, and process for producing the same

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.

Powdery flame retardant

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.

Crosslinked phenoxyphosphazene compounds, flame retardants, flame-retardant resin compositions, and moldings of flame-retardant resins

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.

Crosslinked phenoxyphosphazene compounds, process for the preparation thereof, flame retardants, flame-retardant resin compositions, and moldings of flame-retardant resins

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 99.9% based on the total amount of the phenyl groups in the phosphazene compounds, (c) 1 to 60 parts by weight of an inorganic fibrous substance and (d) 1 to 60 parts by weight of magnesium hydroxide.

Flame-retardant aromatic polyamide resin composition and molded object

Flame-retardent resin compositions compring thermoplastic resin, thermotropic liquid crystal polymer, and hoalogen-free phosphazen compound

A process for stabilizing an aqueous solution of an acrylic or methacrylic hydrazide polymer by adding to the aqueous solution, at least an equal amount of hydrazine hydrate and/or a water-soluble alkaline earth metal salt of an inorganic acid based on the weight of the acrylic or methacrylic hydrazide polymer.

Growing community of inventors

Tokushima, Japan

Tadao Yabuhara