Mitsubishi Gas Chemical Company, Inc.

Masafumi Shimpo

Mutsuhiko Takeda

Minoru Kakuda

Kiyoshi Yoshida

Norio Takeda

Osamu Aoki

Takanari Nawata

Shuzabu Sakaguchi

Toshiaki Kohzaki

Hidechika Wakabayashi

Tetsuo Koshitsuka

Yoshiyuki Aoki

Toshiaki Kanada

Hisashi Sakaitani

Toshiaki Kozaki

Seikyu Jinnouchi

Toshie Takahashi

Akiko Kimura

There is herein disclosed a process for preparing a carboxypolysaccharide by oxidizing a polysaccharide with a combination of a transition metal compound and an oxidizing agent, said process comprising the step of separating the transition metal from a reaction mixture with a chelating agent. According to the present invention, the transition metal can be removed to a low concentration of less than 100 ppm from an aqueous solution including the transition metal and the tricarboxypolysaccharide. The process of the present invention is important to reduce the loss of a transition metal catalyst such as the ruthenium catalyst and to industrially manufacture a purified tricarboxypolysaccharide.

Process for preparing carboxypolysaccharide

A process for producing a thiourea dioxide fluid by mixing thiourea and a peroxide, or thiourea, a peroxide and a reaction catalyst, or thiourea, a peroxide, a reaction catalyst and a chelating agent, in the absence or presence of pulp and a process for bleaching pulp by the use of the thiourea dioxide fluid produced by the above process economically advantageously with a small chemicals loss and by small consumption of energy.

Process for producing thiourea dioxide

An insect-proofing agent comprising 1,3,5-trioxane as an active ingredient is disclosed. This insect-proofing agent has a high insect-proofing action and gives no irritating odor, and the insect-proofing agent is not toxic to human bodies and has a high safety. Furthermore, this insect-proofing agent causes no discoloration in metallic substance such as silver thread, gold threads and spangles used for clothing decoration. This insect-proofing agent is effectively applied in the form of a solid preparation, an aqueous solution or an organic solvent solution.

Moth-proofing method using trioxane as sole active

By incorporating a liquid or solid silicone or paraffin into 1,3,5-trioxane, agglomeration of trioxane particles and adhesion of the trioxane to a machine wall or the like can be prevented. The silicone or paraffin is used in an amount of 0.003 to 1% by weight.

Trioxane composition and insect-proofing agent

Disclosed is a composition comprising trioxane and an assistant aiding in the insect-proofing action of trioxane or controlling its vapor pressure.

Disclosed is a hygroscopic insect-proofing composition, and more particularly a trioxane-containing composition which is useful in insect-proofing and damp proofing of clothing.

Hygroscopic insect-proofing composition

Disclosed is a composition comprising 1,3,5-trioxane, and more particularly a stability-improved trioxane composition.

Stability-improved trioxane composition

An improved process for producing benzophenone-azine in which a catalyst can be removed, recovered and recycled is disclosed. The process comprises the steps of:

Process for producing benzophenone-azine

A process for continuously preparing benzophenone-azines comprising oxidizing benzophenone-imines with molecular oxygen or a molecular oxygen-containing gas in the presence of a copper halide catalyst is disclosed. The oxidation reaction is carried out in a multistage system under an oxygen partial pressure gradually decreasing from the former stage to the latter stage and at a conversion gradually decreasing from the former stage to the latter stage, while controlling the conversion so that the molar ratio of the benzophenone-imines to the copper halide in the final stage be maintained at 1 or more. By the process, the continuous reaction can stably be performed at a high conversion of the benzophenone-imines without involving insolubilization and sedimentation of the catalyst.

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Kashiwa, Japan

Masafumi Shimpo