Formaldehyde → Melamine formaldehyde

Participants

Reaction Conditions

Reaction Steps

In 100 parts of a 5% aqueous solution of pH 4.0 obtained by dissolving styrene-maleic anhydride copolymer and a small amount of sodium hydroxide, 80 parts of an oil Nisseki Hisol N-296 (a trade name mfd. by Nippon Petrochemicals Co., Ltd.) dissolving 2.5 parts of 3-diethylamino-7-chlorofluofluoran was emulsified. A melamine-formaldehyde precondensate was prepared by mixing 10 parts of melamine, 25 parts of a 37% formalin solution and 65 parts of water, making the pH of the mixture 9.0 with sodium hydroxide, and heating the mixture at 60° C. for 15 minutes to make transparent. The precondensate was added to the above-mentioned emulsion and stirred for 4 hours while maintaining at 60° C., followed by cooling to room temperature. The resulting microcapsule dispersion had a solids content of 45%.

Provenance & Evidence