Patent GB-987432-A (GB)
Title: Stable aqueous emulsions from water-insoluble epoxy resins and water-insoluble aminoplasts
IPC: D06M15/423
Filed: 1961-06-27
Abstract: Oil-in-water emulsions contain a mixture of 3-85% by weight of a water-insoluble curable viz. epoxy compound having an epoxide equivalency greater than 1, and 97-15% of a water-insoluble curable aminoplast resin.  They may also contain a protective colloid, and a non-ionic or ionic emulsifying agent, many of which are referred to. Many suitable epoxy compounds are referred to. Examples use: Epoxide A-a diglycidyl ether of 4,41-dihydroxydiphenyldimethyl methane; Epoxide B-an epoxidized acetal from tetrahydrobenzaldehyde and 1,1 - dimethylolcyclohexene - 3; Epoxide C-Epoxidized ester obtained by condensation of 2 mols. of 2-methyl-tetrahydrobenzaldehyde; Epoxide D-vinyl cyclohexene di-epoxide; Epoxide E-glycidyl ether of 3,4-epoxy-dicyclopentan - 8 - ol; Epoxides F, G and H-partially epoxidized polybutadienes; Epoxide I-a condensate of 4,41-dihydroxydiphenyl-dimethylmethate and epichlohydrin. The aminoplasts used are water-insoluble methylol compound of urea or an aminotriazine, which have been etherified with mono-alcohols containing 3-10 carbon atoms.  Some suitable alcohols are propanol; butanol; amyl alcohols; hexyl alcohols; cyclohexanol, 2-ethyl hexanol; nonyl alcohol; 2,6-dimethyl-4-heptanol; tetrahydrofuran - 2 - methanol; 2,2 - dimethyl - 1 - butanol; 2,2,4 - trimethyl - I - pentanol; 2-propyl-1-heptanol. The emulsions, with or without additives have a wide variety of applications e.g. stiffening textile materials, paper or pasteboard, for which purpose it preferably includes an acidic curing agent, many examples of which are listed, and may also include starch and/or urea.  The emulsions may also, together with a curing catalyst, if desired, make coatings on substrates of glass, metals or building materials; or be used as binders for pigments or fibre tufts. Aminoplasts used in the examples are:  A. A butanol solution of dimethylolmelamine ether containing two n-butyl ether groups.  B. butanol solution of hexamethylolmelamine ether containing 6 n-butyl ether groups.  C. propanol solution of dimethylolmelamine ether with about two n-propyl ether groups.  D. isobutanol solution of dimethylolmelamine ether with two iso-butyl ether groups.  E. butanol solution of dimethylolbenzoguanamine ether during two n-butyl ether groups.  F. butanol solution of dimethylolurea ether having 2 n-butyl ether groups.  Example 1 is similar to the many others. Epoxide A is dispersed in aqueous polyvinyl alcohol with an ethylene oxide adduct of cetyl alcohol.  Aminoplast A is emulsified in water containing an ethylene oxide adduct of hydroabityl alcohol, cross-linked with hexamethylene diisocyanate.  The emulsions are mixed, and used together with zinc fluoborate, or with urea, potato starch and aluminium sulphate, or with potato starch and aluminium sulphate for stiffening collars by impregnation, followed by drying and curing.ALSO:Aqueous oil-in-water emulsions containing an epoxy resin and an aminoplast (see Division C3) are suitable for making coatings, e.g. by spreading or spraying on substrata, such as building materials, glass or metal, e.g. iron, aluminium or copper.  The emulsions may include curing agents and application is followed by curing for 10-60 minutes at 120-240  DEG C., or for 1-2 minutes at 300  DEG C.  In Example 15, emulsions containing zinc fluoborate are spread on aluminium sheets and cured for 10 minutes at 150  DEG C. In Example 18, emulsions are diluted with water and brushed on to sheets or bars of aluminium, or are diluted with less water and the sheets or bars are coated by dipping.  The coatings are dried for 45 minutes at 180-200  DEG C.ALSO:Fibrous material is stiffened by aqueous oil-in-water emulsions of an epoxy resin and an amino-plant (see Division C3) containing an acid curing agent.  The emulsions are especially useful for textile material, e.g. stiffening collars, but may also be used for stiffening paper or plasterboard, or as binders for fibre tufts.  Starch and/or urea may be added to the textile stiffening emulsions and aluminium sulphate is an advantageous curing agent. Impregnation is followed by drying and curing.  Stiffening effects may be imparted to native, mercerised or regenerated cellulose materials, acetylcellulose, wool, silk, polyamides, polyurthanes, polyolefines, polyacrylonitrile or polyesters, e.g. as yarns, fleeces, felts, woven or knitted fabrics.  In Example 1, aqueous emulsions containing an epoxy resin from epichlorohydrin and 4, 41-dihydroxydiphenyl-dimethyl methane, as butanol solution of a dimethylolmelamine butyl ether, polyvinyl alcohol, an ethylene oxide adduct of cetyl alcohol, an ethylene oxide adduct of hydroabutyl alcohol cross-linked with hexamethylene diisocyanate, and trithanolamine to bring the pH to 7 are used for collar stiffening material, (d) with added zinc fluoborate, (e) with added potato starch, urea and aluminium sulphate, and (f) p  with added potato starch and aluminium sulphate.  Example 14 describes similar treatments of cotton fabric.