Melamine formaldehyde → Formaldehyde
Reaction equation
[CH2:1]=[O:2].[N:3]1[C:10]([NH2:11])=[N:9][C:7]([NH2:8])=[N:6][C:4]=1[NH2:5].[NH2:12][C:13]([NH2:15])=[S:14].C=O.N1C(N)=NC(N)=NC=1N.NC(N)=S.C=O>>[N:3]1[C:10]([NH2:11])=[N:9][C:7]([NH2:8])=[N:6][C:4]=1[NH2:5].[NH2:12][C:13]([NH2:15])=[S:14].[CH2:1]=[O:2]Participants
Procedure
The prepolymer for use in the present invention is produced from melamine, thiourea and formaldehyde, or from a melamine-formaldehyde prepolymer combined (hereinafter referred to as M/F prepolymer) with a thiourea-formaldehyde prepolymer (hereinafter referred to as TU/F prepolymer). The single use of a melamine-thiourea-formaldehyde prepolymer(hereinafter referred to as M/TU/F prepolymer) obtained by the reaction of melamine, thiourea and formaldehyde, or the combined use of M/F prepolymer and TU/F prepolymer is adoptable. The M/F prepolymer referred to herein may be any one of the melamines such as mono- to hexamethylol melamine, a mixture of methylol melamines different in the degree of hydroxymethylation or a mixture of melamine, formaldehyde and at least one of the methylol melamines. In addition, a transparent colloidal solution obtained by treating the methylol melamine of a degree of polymerization of 2 to 10 with hydrochloric acid, that is, a solution containing the oligomer obtained by further promoting the reaction between melamine and formaldehyde may be used as M/F prepolymer. M/F prepolymer can be easily obtained by heating a mixture of melamine and an aqueous solution of formaldehyde under a basic condition, and the thus obtained aqueous solution of M/F prepolymer can be served for microencapsulation.
Sources & evidence
- ORD record
- ord-2f3721c5dc7d4c2dbb468da72dc45618
- Source dataset
- uspto-grants-1985_12
- Patent number
- US04562116
Reaction notes
Loading…