Patent GB-650977-A (GB)
Title: Manufacture of stable dry preparations of hardenable binding agents
IPC: C08J3/16
Filed: 1948-03-19
Abstract: Stable dry powders which may be redispersed in water are obtained by evaporating to dryness the emulsions described in Specification 645,023 which comprise solutions of an alcohol-amide-formaldehyde condensate emulsified in an aqueous solution containing a protein, and urea or thiourea.  Spray or drum drying preferably under vacuum may be employed.  To the original emulsions or to the dried emulsions which have been dispersed may be added water-soluble ethers of methylol carbamides, e.g. dimethylol urea dimethyl ether or hexamethylol melamine methyl ether.  Examples describe the formation of emulsions which are subsequently evaporated to dryness comprising (1) inner phase: urea-formaldehydebutanol resin dissolved in butanol and mono-chlorobenzene and, outer phase: an aqueous solution of acid casein, borax, urea, thiourea, sulphonated castor oil, and sodium citrate; (2) inner phase as (1), outer phase: aqueous fish glue and urea; (3) inner phase: urea-formaldehyde resin etherified with butanol or benzyl alcohol and dissolved in butanol or benzyl alcohol and tri-chlorethylene; outer phase: aqueous solution of casein, urea, triethanalamine and borax; (4) inner phase: as in (1), outer phase: aqueous casein, urea, thiourea, and borax, the emulsion being then mixed with a solution of dimethylol urea dimethyl ether or hexamethylolmelamine methyl ether; (5) inner phase: butanol modified urea-formaldehyde resin in butanol, outer phase: aqueous gelatine, thiourea and glycerine; (6) inner phase: a cyclohexanol modified urea-thiourea-formaldehyde resin dissolved in cyclohexanol, outer phase: aqueous casein, urea, dicyandiamide and ammonium thiocyanate; (7) inner phase: butyl modified methylol melamine dissolved in butanol and benzene, outer phase: aqueous casein, urea, thiourea, borax or trisodium phosphate, and titanium white; (8) inner phase: as in (1), outer phase: aqueous purified acid casein, urea, thiourea, and borax.  The emulsion is mixed with an aqueous suspension of organic pigment (e.g. by coupling diazotized 2 : 5-dichloraniline with b -oxy naphthoic and orthoanisidine), casein, urea, borax, and highly sulphonated castor oil; (9) inner phase: urea-formaldehyde-butanol resin in butanol containing also copper phthalocyanine, outer phase: aqueous casein, urea, thiourea, sodium hydroxide and phosphate buffer pH6.7.  The emulsion is mixed with an aqueous suspension of copper phthalocyanine, casein, sodium hydroxide, urea, thiourea, and p  sulphoricinoleate.  The dispersions on re-forming are used (1) to (6), as adhesives, (7) for producing matt effects on artificial silk, and (8) and (9) for printing textiles.ALSO:Stable dry preparations, which on re-dispersal in water with or without organic solvents, may be used for printing and delustring textiles, are, prepared by evaporating to dryness an emulsion of the kind described in Specification 645,023 containing organic or inorganic pigments.  Such emulsions comprise a solution in a water-immiscible solvent of a condensate of formaldehyde, an amide capable of forming a hardenable aminoplast with formaldehyde and a water-immiscible alcohol, the solution being emulsified in water containing at least one protein and urea, thiourea, or a mixture of the two.  The materials used in making the resin and the emulsion are as specified in Specification 645,023, and there may be added biuret, dicyandiamide, softeners such as tri-cresyl phosphate or glycerine, fillers, pigments, emulsifiers, anti-foaming agents, wetting agents, hydrophobic agents such as paraffin and other waxes, buffers and hardening accelerators, e.g. ammonium thiocyanate, diethyl tartrate. Before or after drying may be added water-soluble ethers of methylol carbamide, e.g. dimethylol urea dimethyl ether or hexamethylol melamine methyl ether.  The drying may be effected by spray- or drum-drying, or evaporation under reduced pressure.  Examples describe (7) a suspension of titanium white in an emulsion of hexamethylol melamine butyl ether dissolved in butyl alcohol and benzene and dispersed in an aqueous solution of acid casein, urea, thiourea, borax or trisodium phosphate.  The product is dried under reduced pressure.  It is re-dispersed in water used to impregnate artificial silk, which on drying at 100 DEG  C. gives a matt effect. (8) An aqueous suspension of a pigment, e.g. the product from diazo-2 : 5-dichloraniline and b  - oxynaphthoic acid o-aniside, casein, urea, borax, and sulphonated castor oil which is mixed with an emulsion of urea-formaldehyde-butanol resin dissolved in butanol and dispersed in water containing casein, urea, thiourea and borax.  The mixture is spray-dried and heated under reduced pressure.  The product is re-dispersed in water for use as a printing colour or foulard liquor.  (9) A lacquer containing copper phthalocyanine urea-formaldehyde-butanol resin in butanol is dispersed in a solution containing casein, urea, thiourea, sodium hydroxide and phosphate buffer, and mixed with an aqueous suspension of copper phthalocyanine, casein, sodium hydroxide, urea, thiourea and sulphoricinoleate.  The product is drum dried. On redispersion, the product containing pigment in both phases is used as a printing colour.  Specification 597,390 also is referred to.ALSO:A process for making stable dry preparations of hardenable binding agents which can be re-dispersed in water with or without organic solvents comprises evaporating to dryness an emulsion of the kind described in Specification 645,023.  Such emulsions comprise a solution in a water-immiscible solvent of a condensation product of formaldehyde, an amide capable of forming a hardenable aminoplast with water and a water immiscible alcohol, the solution being emulsified in an aqueous solution of urea, thiourea or a mixture of the two, and a protein. The materials used in making the condensation product and the emulsion are as specified in Specification 645,023.  There may be added biuret, dicyandiamide, softeners such as tricresyl phosphate or glycerine, fillers, pigments, emulsifiers, anti-foaming agents, wetting agents, hydrophobic agents such as waxes, buffers, and hardening agents, e.g. ammonium thiocyanate, or diethyl tartrate. Before or after drying may be added water-soluble ethers of methylol carbamide, e.g. dimethylol urea dimethyl ether or hexamethylol melamine methyl ether.  Drying is effected by spray- or drum-drying or heating under reduced pressure. Examples describe the application of the process to emulsions comprising as inner and outer phases respectively: (1) a urea-formaldehyde-butanol resin dissolved in mono-chlorobenzene and an aqueous solution of acid casein, borax, urea, thiourea, sulphonated castor oil and sodium citrate; (2) inner phase as in (1), and outer phase an aqueous solution of fish glue and urea; (3) urea-formaldehyde-butanol or benzyl alcohol resin in butanol or benzyl alcohol and trichlorethylene, and an aqueous solution of urea, casein, triethanolamine and borax; (4) inner phase as in (1), outer phase as in (3), the emulsion being mixed with the methyl ether of dimethylol urea or hexamethylol melamine; (5) urea-formaldehyde - butanol resin dissolved in butanol, and an aqueous solution of gelatine thiourea, and glycerine; (6) a urea-thioureaformaldehyde-cyclohexanol resin dissolved in cyclohexanol, and an aqueous solution of casein, urea, dicyandiamide, and ammonium thiocyanate; (7) melamine - formaldehyde - butanol resin in butanol and benzene, and an aqueous mixture of casein, urea, thiourea, borax, or trisodium phosphate, and titanium white; (8) inner phase as in (1), and an outer phase of aqueous purified acid casein, urea, thiourea and borax.  The emulsion is mixed with an aqueous suspension of an organic pigment containing casein, urea, borax and sulphonated castor oil; (9) urea-formaldehydebutanol resin in butanol containing also copper phthalocyanine, and an aqueous solution of casein, urea, thiourea, sodium hydroxide, and phosphate buffer. The emulsion is mixed with an aqueous suspension of copper phthalocyanine, casein, sodium hydroxide, urea, thiourea and sulpho-ricinoleate.  The dried products may be re-dispersed in water and used as: (1) to (6) adhesives; (7) delustring artificial silk; (8) and (9) printing textiles.