Patent GB-344401-A (GB)
Title: Improvements in and relating to resinous compositions and lacquers
IPC: C09D167/08
Filed: 1929-08-30
Abstract: Lacquers and varnishes are prepared from a resinous condensation product, obtained by combining an alkyd resin with a urea or thiourea-formaldehyde condensation product in the presence of a monohydric alcoholic solvent.  A drying oil or drying oil fatty acid may be added to the components from which the resin is formed.  By incorporating an acid or acid producing substance such as sulphuric acid, sodium hydrogen sulphate, chlorosulphonic acid, sulphuryl chloride, benzene-sulphonic acid, hydrochloric acid, p-toluene-sulphonic chloride, trichloro-acetic acid, tartaric acid, boric acid and malic acid, the finished resin hardens rapidly at room temperatures, otherwise a heat treatment is necessary for hardening. In an example, some of the finished resin is dissolved in methylated spirits and toluene.  The lacquer is clarified by filtration and further treated with small quantities of acid substances and solvents, e.g. a solution of tartaric acid and boric acid in glycol monoethyl ether, methylated spirits and toluene.  The acid catalyzed resin may be used with cellulose esters and ethers, e.g. nitrocellulose in lacquers.ALSO:An alkyd resin is combined with a urea or thiourea-formaldehyde condensation product by heating in a monohydric alcoholic solvent. If desired, a drying oil or drying oil fatty acid may be added to the components from which the resin is formed.  Suitable alcohols are ethylene chlorhydrin, dichlorhydrin glycol, monoethyl ether, butyl alcohol, and cyclohexanol.  By incorporating a relatively small quantity of an acid or acid-producing substance, the finished resin hardens rapidly at room temperatures, otherwise a heat treatment is necessary for hardening. Acids specified are sulphuric, chloro-sulphonic, benzenesulphonic, hydrochloric, trichloracetic, boric and malic acids.  Acid substances mentioned are sodium hydrogen sulphate, sulphuryl chloride, and p-toluenesulphonic chloride.  The acid catalyzed resin may be used in the preparation of lacquers or in admixture with other materials such as cellulose esters and ethers with which it is compatible.  In such cases the composite film at room temperatures rapidly becomes insoluble in solvents, which facilitates the application of a second coat.  In an example phthalic anhydride, glycerol and castor oil are heated together at 200 DEG  C. for 3-4 hours, during which time a current of carbon dioxide or nitrogen is passed through the mixture. After cooling rapidly, a pale yellow resin is obtained soluble in hot alcoholic solvents.  Some of this resin is dissolved in butyl alcohol and the hydrogen ion concentration adjusted to 10-6 by the addition of alcoholic caustic potash.  Urea is added and heat applied, and when solution is complete paraformaldehyde is added to the hot solution.  The mixture is refluxed until the paraformaldehyde has completely reacted, and the whole is then diluted with solvent naphtha.  A clear pale yellow lacquer is obtained which is compatible with nitrocellulose.  In another example, phthalic anhydride, glycerol and castor oil are heated together to give a pale brown resin which is dissolved in butyl alcohol and methylol urea added. The whole is refluxed until reaction is complete and then dissolved in solvent-naphtha, giving a brown lacquer which produces hard, flexible, transparent coatings.  In a third example, a resin prepared as in the first example above is dissolved in glycol monoethyl ether, dimethylol urea is added, and the mixture heated. The product is dissolved in solvent-naphtha and methylated spirits and produces a lacquer which gives hard flexible coatings highly resistant to water. In a further example a resin prepared as in the first example above is dissolved in glycol monoethyl ether, and dimethylol urea is added. The mixture is refluxed, and methylated spirits and toluene added; the lacquer thus obtained may be treated in either of the following ways: (i) The lacquer is treated with dilute sulphuric acid dissolved in glycol monoethyl ether, toluene, and methylated spirits; (ii) a small quantity of benzenesulphonic acid is added; (iii) the lacquer is treated with a solution of tartaric and boric acids in glycol ethyl ether, toluene, and methylated spirits; (iv) the lacquer is mixed with nitrocellulose dope solution and diluted with nitrocellulose mixed solvent, after which a little dilute sulphuric acid is added. Films obtained from this mixture dry rapidly to transparent flexible coatings which rapidly become insoluble in nitrocellulose solvents.ALSO:Plastic compositions containing artificial resins.-A resinous condensation product which is stated to be applicable to the bonding of mica or other laminated material and to the preparation of moulding powders and compositions with or without the addition of fillers is obtained by combining an alkyd resin with a urea or thiourea-formaldehyde condensation product in the presence of a monohydric alcoholic solvent.  A drying oil or drying oil fatty acid may be added to the components from which p the resin is formed.  By incorporating a relatively small quantity of an acid or acid producing substance, the finished resin hardens rapidly at room temperatures, otherwise a heat treatment is necessary for hardening.