解説22.各種接着剤の基礎と進展
(4) アミノ系樹脂接着剤
2020 年 56 巻 7 号 p. 289-294
詳細
2020 年 56 巻 7 号 p. 289-294
Amino resins are synthesized by addition reactions and condensation reactions of amino compounds, such as urea and melamine, and formaldehyde. Amino resins have methylol groups, methylene bonds, dimethylene ether bonds and methyl ether groups. Content rates of these functional groups included in amino resins decide the adhesion performance, such as curing rate, bonding strength, water resistance and formaldehyde emission. Chemical structures of amino resins have been investigated by 13C-NMR analysis, etc. Urea-formaldehyde resin and melamine-formaldehyde resin, representative amino resin adhesives, are mainly used in the manufacture of wood-based boards. Resent issues about amino resins are reduction of formaldehyde emission from wood-based boards. To reduce the formaldehyde emission while keeping the bonding performance, co-condensations between melamine and urea resins or using of isocyanate compounds with amino resin adhesives have been applied.
