Urea resin - Nyousojushi

Also known as urea resin. A thermosetting resin obtained by the addition condensation reaction of urea and formaldehyde. One of the amino resins. It is obtained by heating urea and formalin in neutral or slightly alkaline conditions to react with each other, going through N -hydroxyurea and N,N' -bis(hydroxy)urea, and then forming methylene crosslinks in a slightly acidic environment. Additives and fillers (such as cellulose powder) can be added to the initial product to make a molding compound, or it can be concentrated and ammonium chloride or the like can be added to make an adhesive, or the hydroxymethyl groups can be alkylated with alcohols and alkyd resin added to make a paint. It can also be used as a fiber and paper processing treatment agent by adding an acid catalyst and other additives.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

ユリア樹脂ともいう．尿素とホルムアルデヒドの付加縮合反応によって得られる熱硬化性樹脂．アミノ樹脂の一つ．尿素とホルマリンとを中性あるいは微アルカリ性で加熱して反応させ，N-ヒドロキシ尿素，N,N′-ビス(ヒドロキシ)尿素を経て，ついで微酸性中でメチレンによる橋かけを生成させて得る．初期生成物に添加剤，充填剤(セルロース粉末など)を加えて成形用コンパウンドとしたり，濃縮して塩化アンモニウムなどを加えて接着剤とし，あるいはヒドロキシメチル基をアルコール類でアルキル化し，アルキド樹脂を添加して塗料とする．また，酸性触媒とほかの添加物を加えて，繊維，紙加工処理剤とするなどの用途がある．

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