摘要:
A process for the preparation of polyurethane foams modified with melamine-formaldehyde precondensates, in which the precondensates employed are storage-stable, aqueous 40-85% strength by weight resin solutions which are obtained by condensing melamine with formaldehyde in a molar ratio of 1:1.1-1.75 in aqueous solution at a pH which, at least periodically, is above 8, and at from 60 to 130.degree. C., until one part by volume of resin solution can be diluted with from 0.5 to 4 parts by volume of water at 20.degree. C. without causing a persisting cloudiness.
摘要:
Binders comprise A) an aminotriazine derivative in which the primary amino groups of the triazine are methylolated on average with at least one mole of formaldehyde per mole of primary amino groups, and these methylol groups are etherified on average with at least 0.5 mol of primary alcohol per mole of methylol group and the primary alcohols are a mixture containing a) 0.5-99.5 mol % of a C.sub.1 -C.sub.4 -alkanol and b) 99.5-0.5 mol % of an alcohol of the formula R.sup.1 --O--�R.sup.2 --O!.sub.n --R.sup.3 --OH I, in which R.sup.1 is C.sub.1 -C.sub.24 -alkyl or C.sub.6 -C.sub.12 -aryl which may be unsubstituted or substituted by from one to three C.sub.1 -C.sub.8 -alkyl groups, and R.sup.2 and R.sup.3 independently of one another are C.sub.2 -C.sub.8 -alkylene and n is an integer from 1 to 100, or of a mixture of higher-boiling alcohols having a boiling point of above 120.degree. C. at 1 bar which contains at least 10 mol %, based on the higher-boiling alcohols, of alcohols of the formula I, and B) a radical polymer, polycondensation product or polyadduct which is crosslinkable with the aminotriazine derivative.
摘要:
Cathodic coating agents which are rendered water-dilutable by the addition of an acid, contain binder systems possessing basic nitrogen groups and may or may not contain pigments, dyes, fillers, solvents, antioxidants, other surface coating assistants and/or additional crosslinking components, the binder system containing sulfonate and/or phosphonate groups or the esters of these groups in an amount of from 0.05 to 3% by weight, and the preparation of such products.The novel coating agents are useful for the cathodic electrocoating of electrically conductive substrates.
摘要:
A process for the preparation of curable etherified aminoplast resins based on urea/aldehyde polycondensates, and the preparation of surface coating resins.Urea is first reacted with an .alpha.,.alpha.-dialkylaldehyde, as much as 50 mol % of which may be replaced by formaldehyde, in a molar ratio urea/aldehyde of about 1:2, at from 50.degree. to 120.degree. C., in the presence of an acid and in the presence or absence of an alcohol or of other organic solvents, and the 2-oxohexahydropyrimidine derivative obtained in this cyclocondensation is then condensed with formaldehyde in the presence of one or more alcohols and an acid.These aminoplast resins are useful as both acid-curable resins and as resins for baking finishes.
摘要:
Radiation-curable urethane acrylate compounds containing amine and urea groups and based on di- or polyisocyanates, hydroxy compounds and amines contain secondary or tertiary amino groups which are bonded to isocyanate via hydroxyl groups and are obtainable by an addition reaction of primary or secondary amines with hydroxyacrylates.
摘要:
N,N',N"-tris-(2-hydroxyethyl)-melamine, if required, as a mixture with N-mono- and N,N'-bis-(2-hydroxyethyl)-melamine, is prepared by reacting melamine with ethanolamine in the presence of an acidic catalyst by a method in which the reaction is carried out at from 120.degree. to 250.degree. C. using an excess of ethanolamine, and the molar ratio of free ethanolamine to the sum of free and converted melamine is not permitted to fall below 4:1 during the entire reaction time, and the stated (2-hydroxyethyl)-melamines are used as modifiers in the prepartion of aminoplast resins which are suitable for laminating surfaces.
摘要:
A process for the preparation of a radiation-curable acrylate composition, wherein to compounds A containing at least 2 acrylic groups there are added benzophenone derivatives which are not copolymerizable by free-radical copolymerization and which contain at least one primary or secondary amino group or a hydroxyl group or a mercapto group.
摘要:
Radiation-curable binders which are obtained by reactingA) an amine/formaldehyde condensate having a molar ratio of formaldehyde to amino groups of from 1:1 to 2:1 withB) one or more esters, having a free hydroxyl group, of acrylic acid or of methacrylic acid with polyalcohols which contain from two to four alcoholic hydroxyl groups, from 0.1 to 0.3 hydroxyl equivalent of component B) being used per methylol equivalent of component A),in the presence of a strong acid are suitable for use in coating materials.
摘要:
A process for the preparation of etherified or non-etherified aminoplast resins, wherein an aminotriazine of the general formula (I) ##STR1## where X is hydrogen, alkyl, phenyl, alkylphenyl or --NH.sub.2, is reacted with a .beta.-hydroxyaldehyde of the general formula (II) ##STR2## where R', R" and R'" are identical or different and each is hydrogen or alkyl, or R" and R'", together with the .alpha.-carbon atom, are a cyclopentane or cyclohexane ring, and R" and/or R'" can be hydroxyalkyl and R" can be phenyl, the reaction being carried out in the presence of not less than one alcohol and an acid catalyst for the preparation of etherified aminoplast resins and in the presence or absence of an acid catalyst for the preparation of non-etherified aminoplast resins. The aminoplast resins prepared according to the invention can be used as surface-coatings raw materials.