Formaldehyde → Melamine formaldehyde

Participants

Reaction Conditions

Reaction Steps

80 Parts of a solution of 4.8 parts of 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide (CVL) in 1,1-diphenylethane was emulsified into 100 parts of 5% aqueous solution of styrene-maleic acid copolymer containing a small quantity of sodium hydroxide and having a pH value of 4.0. On the other hand, 10 parts of melamine, 25 parts of 37% aqueous solution of formaldehyde and 65 parts of water were mixed together. The mixture was adjusted to pH 9 with sodium hydroxide and heated to 60° C., whereby the mixture became transparent in 15 minutes to give a melamine-formaldehyde precondensate. It was added to the above-mentioned emulsion and stirring was continued at a liquid temperature of 60° C. In 30 minutes, formation of capsule was observed, so that the mixture was cooled to room temperature. The microcapsule dispersion thus obtained had a solid content of about 45%.

Provenance & Evidence