Patent GB-832203-A (GB)
Title: Water-soluble melamine-formaldehyde condensation polymers
Inventor: SUEN WILLIAM WOODING TZENG JIU
IPC: C08G12/34
Filed: 1956-04-26
Abstract: Water-soluble melamine-formaldehyde - aliphatic polyamine resins, where the polyamine has a C : N atom ratio not greater than 4 : 1 (for preparation see Group IV (a)), are used as anchoring agents between a wide variety of bases and top coats. The amines specified are alkylene and polyalkylene polyamines, hydroxyl polyamines, gueridine compounds and condensation products of ammonia or alkylene or polyalkylene amines with difunctional halohydrines or dihaloalkanes.  The resins are applied by sponging, spraying, rolling or dipping, generally in the form of an aqueous solution, with or without glycerol, and may be mixed into the aqueous phase of cationic latex paints or wax emulsions.  The coated base is then normally dried at room temperature and the resin later polymerized in situ, preferably at 180-250 DEG  F.  Bases specified are regenerated non-fibrous cellulose, ethyl cellulose, cellulose acetate, cellulose nitrate, chlorinated rubber; polyethylene terephthalate, polyvinylidene chloride, polymethyl methacrylate, polystyrene, vulcanized rubber, urea-, melamine- and phenolformaldehyde resins; Al, Sn, Zn, Cr, Mg, Cu, steel, tin-plated steel, brass, bronze, "Duralumin" (Registered Trade Mark), stainless steel, pewter; glass, ceramics, glaced or unglazed, brick, concrete, plaster, asbestos; lumber, plywood, wood veneer, fibreboard, maple; leather, hair, finger nails, horn, parchment, casein plastics; as well as fibrous compositions and textiles (see Group VIII).  Top coats specified are nitrocellulose, cellulose acetate, methyl cellulose, deacetylated chitin, polyethylene, rubber, chlorinated rubber, rubber hydrochloride, ethyl cellulose, butyl methacrylate, methyl methacrylate, montan wax, beeswax, canauba wax, printed legends, revenue stamps, decorations, red wax pencil, a lacquer of soya and castor oil modified glycerol phthalate with an alkylated melamine-formaldehyde resin, a lacquer of a co-polymer of hydroxyethyl methacrylate, styrene and butyl methacrylate with butylated melamine-formaldehyde resin and titanium dioxide, a xylene solution of a glyceryl phthalate alkyl resin, a xylene solution of a linseed oil modified glyceryl phthalate resin and an acrylonitrile-styrene co-polymer with titanium dioxide, and an acetone and lower alkyl ester solution of nitrocellulose.  Various combinations of bases and top coats are described in Examples 16-26 and 30-33.ALSO:Water-soluble melamine-formaldehyde resins are prepared by reacting melamine, formaldehyde and an aliphatic polyamine at a temperature of 20-100 DEG  C. until a viscosity of 20-800 cps. (measured at 35% solids and 25 DEG  C.) is obtained, and neutralizing the resultant resin, the formaldehyde being present in an amount greater than 6 mols. per mol. of melamine, and the polyamine having a C:N atom ratio not greater than 4:1 and being present in an amount corresponding to 0.5-10 N atoms per molecule of melamine.  Various methods of preparation are specified: (i) the melamine and formaldehyde are reacted at an alkaline or neutral pH and the polyamine is reacted with this partial polymer at an acid pH, (ii) the melamine is reacted with part of the formaldehyde, the rest of the formaldehyde being added later either (a) at the same time as the polyamine or (b) after neutralization, (iii) the polyamine and formaldehyde are first reacted together and then with the melamine, and (iv) the melamine formaldehyde and polyamine are all reacted together at pH 4.5-6.5.  Aliphatic polyamines specified are ethylene diamine, trimethylene diamine, tetramethylene diamine, propylene diamine, diethylene triamine, triethylene tetramine, tetraethylene pentamine, 3,31-iminobispropylamine and tris-(3-aminopropyl)-amine, N,N - (2 - hydroxyethyl - 21 - aminoethyl)-amine, N,N - (3 - hydroxypropyl - 31 - aminopropyl) - amine, guanidine hydrochloride, nitrate, acetate and carbonate, guanidine and biguanide.  Also included as polyamines are the reaction products of (a) NH3 and a difunctional halohydrin, (b) an alkylene or polyalkylene polyamine and a difunctional halohydrin, and (c) an alkylene or polyalkylene polyamine and a dihaloalkane; difunctional halohydrins include epichlorhydrin, epibromhydrin, and glycerol-a - or b -di-brom- or chlor-hydrins; dihalo alkanes include ethylene and trimethylene dichlorides, trimethylene and ethylene dibromides, and trimethylene diiodide; alkylene or polyalkylene polyamines include ethylene diamine, diethylene triamine, triethylene tetramine, tetraethylene pentamine, 3,31 - imino - bis - propylamine, tris - (3 - aminopropyl)-amine, triethylene tetramine and 1,4-diaminobutane. Such polymers are prepared in Examples (1)-(14).  In Example (15) the resins made in the earlier examples are used to make wet strength paper (see Group VIII).  In Examples (16)-(33) the resin is used as an anchoring agent between a wide variety of bases and top coats (see Groups III and VIII); bases include such materials as cellulose films, synthetic resins, textiles, metals, glass, concrete, wood and finger nails; top coats include cellulose derivatives, synthetic resins and writing materials; the resin of the invention is generally applied in aqueous solution, with or without glycerol, and may be mixed into the aqueous phase of cationic latex paints or wax emulsions. In Examples (28) and (29) laminates are made (see Group VIII).