Chemie Linz Aktiengesellschaft

Wilhelm Dobramysl

Gerhard Stern

Friedl Heger

Hubert Czepel

Hubert Stuckler

Walter Raml

Process for the preparation of pure 1-phenyl-3-carbalkoxy-5-hydroxypyrazoles of the general formula ##STR1## in which R denotes methyl or ethyl, by reaction of acetylsuccinic esters with phenyldiazonium chloride and a base with pK.sub.B value of 3.6 to -1.5 at a pH of 4 to 9 in an aqueous medium to give the corresponding phenylhydrazone, which is cyclized at a pH of 7 to 9.5, with warming and with the addition of ammonia, to give the ammonium salt of the hydroxypyrazole. Compound I is formed by acidification.

Process for the preparation of pure

Process for the preparation of monomeric methylolmelamine which is partially etherified with methanol or ethanol and which contains at least 4 moles of formaldehyde per mole of melamine, by reacting melamine, paraformaldehyde and methanol or ethanol in a single stage reaction, the molar ratio of melamine to formaldehyde to alcohol being 1:5 to 10:6 to 20, in a virtually anhydrous medium, under a nitrogen atmosphere, at a pH of 7 to 8 and a temperature from 50.degree. to 90.degree. C. and with a reaction time of from 3 to 30 hours.

Process for the preparation of partially etherified methylolmelamines

Modified aminoplast resins based on melamine and formaldehyde or urea and formaldehyde, which contain, as modifiers, methylolmelamines having a molar ratio of melamine to formaldehyde of 1:3 to 1:6, which are etherified with mono-alcohols having 1 to 4 carbon atoms, in a ratio of melamine to alcohol of 1:2 to 1:6. These resins are used, in particular, for the production of decorative, glossy-surface laminations.

Modified aminoplast resins containing methylolmelamine etherified with a

A storage-stable lacquer resin which can be baked without yellowing at a low baking temperature, and is based on an alkyd resin, acrylic resin or epoxy resin, is obtained by reacting the resin with a bis- or tris-alkoxyalkylamino-s-triazine which has been obtained by heating a triazine derivative of the general formula: ##STR1## wherein X is an alkyl group having 1 to 4 carbon atoms, a phenyl group or the group ##STR2## and each of R and R' is an alkyl group radical having up to six carbon atoms, at 100.degree. to 200.degree. C. up to a weight loss of 3 to 25%, preferably 5 to 15%.

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Linz, Austria

Wilhelm Dobramysl