Formaldehyde → Melamine formaldehyde

Participants

Reaction Steps

220 Parts of hydrophobic liquid of Example 5 was added to 180 parts of 8.0% aqueous solution of ethylene-maleic anhydride copolymer (EMA-31 of Monsant Co.) adjusted to pH 3.5 as a water-soluble polymer and emulsification was performed in the same manner as in Example 5. Next, 14 parts of melamine, 27 parts of 37% aqueous formaldehyde solution and 133 parts of water were mixed, followed by dissolution with heating at pH 9.0 to obtain a melamine-formaldehyde pre-condensate. This pre-condensate was added to said emulsion, followed by stirring at 70° C. for 2 hours to complete the reaction. Using the resulting microcapsule slurry, an over sheet (CB sheet) for carobonless pressure-sensitive copy paper was prepared in the same manner as in Example 5.

Provenance & Evidence