US 6,207,791 B1 · Low formaldehyde emitting crosslinking agents, process of preparation and curable compositions thereof

Abstract

Described is a liquid, partially alkoxymethylated melamine crosslinker composition having from about 2.6 to about 4.6 moles of combined formaldehyde per mole of melamine, from about 1.4 to about 4.4 moles of alkyl per mole of melamine, from about 1.3 to about 3.4 moles of NH per mole of melamine, a free formaldehyde level of less than about 0.5 weight percent based on 100 percent solids, and an N-methylol level of less than about 6.0 weight percent; processes for its preparation; a low formaldehyde emitting curable composition containing the crosslinker; as well as a method of coating a substrate and substrates so coated.

Claims39

Dependent claims

A liquid partially alkoxymethylated melamine crosslinker composition having from about 2.6 to about 4.6 moles of combined formaldehyde to per mole of melamine;

from about 1.4 to about 4.4 moles of alkyl per mole of melamine;
from about 1.3 to about 3.4 moles of NH per mole of melamine and a free formaldehyde level of less than about 0.5 weight percent based on 100 percent solids, wherein said crosslinker composition is prepared by a process comprising the steps of:
(i) reacting melamine with formaldehyde;
(ii) reacting the product from (i) with an etherifying agent;
(iii) reacting the product from (ii) with an etherifying agent;
then
(iv) reacting the product from (iii) with an etherifying agent.

4 more elements

A liquid partially alkoxymethylated melamine crosslinker composition having from about 2.6 to about 4.6 moles of combined formaldehyde to per mole of melamine;

from about 1.4 to about 4.4 moles of alkyl per mole of melamine;
from about 1.3 to about 3.4 moles of NH per mole of melamine and a free formaldehyde level of less than about 0.5 weight percent based on 100 percent solids, wherein said crosslinker composition is prepared by a process comprising the step of contacting a liquid partially alkoxymethylated melamine crosslinker starting material having greater than about 0.5 weight percent free formaldehyde based on 100 percent solids and greater than about 6 weight percent N-substituted methylol groups based on 100 percent solids, and a reagent selected from the group consisting of an amino group containing compound and an etherification agent, said contacting being carried out at a temperature and length of time sufficient to produce a liquid partially alkoxymethylated melamine crosslinker containing less than 0.5 weight percent free formaldehyde based on 100 percent solids and less than 6 weight percent N-substituted methylol groups based on 100 percent solids.

Dependencies are inferred from the claim text.

Low formaldehyde emitting crosslinking agents, process of preparation and curable compositions thereof

Life of this patent

Low formaldehyde emitting crosslinking agents, process of preparation and curable compositions thereof

Life of this patent

Abstract

Claims39