摘要:
A process for the preparation of stable aqueous aldehyde resin dispersions and for the production of surface coating binders.For this purpose, a melt or highly concentrated solution of a polycondensate of urea and a CH-acidic aldehyde, with or without formaldehyde, is dispersed in water in the presence of an organic protective colloid and, if required, an emulsifier.These aqueous resin dispersions can be used, in combination with other film formers, as surface coating binders.
摘要:
A process for the preparation of a stable aqeuous ketone resin or ketone/aldehyde resin dispersions and a process for the production of surface coating binders. For this purpose, a melt or a highly concentrated solution of the ketone resin or ketone/aldehyde resin is dispersed in water in the presence of an organic protective colloid. These aqueous resin dispersions can be used, in combination with other film formers, as surface coating binders.
摘要:
Urea-aldehyde polycondensates usable as surface coating binders are obtainable by step-wise reaction of(a) urea and/or urea derivatives with acidic CH aldehydes in a molar ratio of urea:aldehyde of 1:2 in the presence of acids and at from 60.degree. to 120.degree. C. with(b) a mixture of 3 moles of formaldehyde per mole or urea and 3 moles of an acidic CH aldehyde per mole of urea at from 60.degree. to 120.degree. C. with subsequent removal of the water of reaction and treatment of the reaction mixture with an alkali metal alcoholate at from 80.degree. to 100.degree. C.
摘要:
Resins AB which are dilutable in water following neutralization and have an acid number of from 25 to 160 mg/g, obtainable by reacting mass fractions, based in each case on the sum of the masses of the solids in the reaction mixture, of A from 30 to 90% of at least one acid-functional polymer selected from polyesters, dimerized and oligomerized unsaturated aliphatic carboxylic acids and polymers of olefinically unsaturated monomers, each having an acid number of from 30 to 240 mg/g, and B from 10 to 70% of at least one water-insoluble aldehyde resin or ketone resin obtainable by condensing ketones, ketones together with aldehydes, ketones with urea or aldehydes with urea, having a hydroxyl number from 20 to 300 mg/g, a softening point of from 60 to 140.degree. C. and a number-average molar mass of from 500 to 3000 g/mol.