Water → Formaldehyde

Participants

Reaction Conditions

Reaction Steps

300 g of rosin and 700 g of 75% strength dicyclopentadiene are heated to 260° C. in a 5 liter pressure apparatus. After five hours, the stirred melt is cooled to 160° C. and the apparatus is brought to atmospheric pressure. 710 g of a water-soluble resol obtained from 1,860 g of nonylphenol and 510 g of formaldehyde (processing viscosity 250 mPa.s, residue on drying 68% after heating for one hour at 135° C.) are metered into this melt. With constant removal of water, the mixture is heated to 250° C. until a 50% strength toluene solution reaches a viscosity of 100 mPa.s/23° C. 12.5 g of 3l-aminopropylimidazole are then added, stirring is continued for 1 hour and volatile components are distilled off in vacuo at 50 mbar. 2,100 g of a mineral oil having a boiling point of 240°-270° C. and an aniline point of 72° C. are then allowed to run in. After cooling, the varnish has a viscosity of 10 dPa.s/23° C. It can be used for flusing water-moist pigment cakes and for dispersing pigments.

Provenance & Evidence